blob: 986e2388f031dd3ccb2ceec8c07d0a31b058eed1 [file] [log] [blame]
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001/*
Mingming Cao617ba132006-10-11 01:20:53 -07002 * linux/fs/ext4/inode.c
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003 *
4 * Copyright (C) 1992, 1993, 1994, 1995
5 * Remy Card (card@masi.ibp.fr)
6 * Laboratoire MASI - Institut Blaise Pascal
7 * Universite Pierre et Marie Curie (Paris VI)
8 *
9 * from
10 *
11 * linux/fs/minix/inode.c
12 *
13 * Copyright (C) 1991, 1992 Linus Torvalds
14 *
Dave Kleikampac27a0e2006-10-11 01:20:50 -070015 * 64-bit file support on 64-bit platforms by Jakub Jelinek
16 * (jj@sunsite.ms.mff.cuni.cz)
17 *
Mingming Cao617ba132006-10-11 01:20:53 -070018 * Assorted race fixes, rewrite of ext4_get_block() by Al Viro, 2000
Dave Kleikampac27a0e2006-10-11 01:20:50 -070019 */
20
21#include <linux/module.h>
22#include <linux/fs.h>
23#include <linux/time.h>
Mingming Caodab291a2006-10-11 01:21:01 -070024#include <linux/jbd2.h>
Dave Kleikampac27a0e2006-10-11 01:20:50 -070025#include <linux/highuid.h>
26#include <linux/pagemap.h>
27#include <linux/quotaops.h>
28#include <linux/string.h>
29#include <linux/buffer_head.h>
30#include <linux/writeback.h>
Alex Tomas64769242008-07-11 19:27:31 -040031#include <linux/pagevec.h>
Dave Kleikampac27a0e2006-10-11 01:20:50 -070032#include <linux/mpage.h>
Duane Griffine83c1392008-12-19 20:47:15 +000033#include <linux/namei.h>
Dave Kleikampac27a0e2006-10-11 01:20:50 -070034#include <linux/uio.h>
35#include <linux/bio.h>
Mingming Cao4c0425f2009-09-28 15:48:41 -040036#include <linux/workqueue.h>
Jiaying Zhang744692d2010-03-04 16:14:02 -050037#include <linux/kernel.h>
Andrew Morton6db26ff2011-01-12 16:59:13 -080038#include <linux/printk.h>
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090039#include <linux/slab.h>
Theodore Ts'oa8901d32010-12-17 10:40:47 -050040#include <linux/ratelimit.h>
Theodore Ts'o9bffad12009-06-17 11:48:11 -040041
Christoph Hellwig3dcf5452008-04-29 18:13:32 -040042#include "ext4_jbd2.h"
Dave Kleikampac27a0e2006-10-11 01:20:50 -070043#include "xattr.h"
44#include "acl.h"
Mingming Caod2a17632008-07-14 17:52:37 -040045#include "ext4_extents.h"
Theodore Ts'o9f125d62011-06-27 19:16:04 -040046#include "truncate.h"
Dave Kleikampac27a0e2006-10-11 01:20:50 -070047
Theodore Ts'o9bffad12009-06-17 11:48:11 -040048#include <trace/events/ext4.h>
49
Aneesh Kumar K.Va1d6cc52008-08-19 21:55:02 -040050#define MPAGE_DA_EXTENT_TAIL 0x01
51
Jan Kara678aaf42008-07-11 19:27:31 -040052static inline int ext4_begin_ordered_truncate(struct inode *inode,
53 loff_t new_size)
54{
Theodore Ts'o7ff9c072010-11-08 13:51:33 -050055 trace_ext4_begin_ordered_truncate(inode, new_size);
Theodore Ts'o8aefcd52011-01-10 12:29:43 -050056 /*
57 * If jinode is zero, then we never opened the file for
58 * writing, so there's no need to call
59 * jbd2_journal_begin_ordered_truncate() since there's no
60 * outstanding writes we need to flush.
61 */
62 if (!EXT4_I(inode)->jinode)
63 return 0;
64 return jbd2_journal_begin_ordered_truncate(EXT4_JOURNAL(inode),
65 EXT4_I(inode)->jinode,
66 new_size);
Jan Kara678aaf42008-07-11 19:27:31 -040067}
68
Alex Tomas64769242008-07-11 19:27:31 -040069static void ext4_invalidatepage(struct page *page, unsigned long offset);
Theodore Ts'ocb20d512010-10-27 21:30:09 -040070static int noalloc_get_block_write(struct inode *inode, sector_t iblock,
71 struct buffer_head *bh_result, int create);
72static int ext4_set_bh_endio(struct buffer_head *bh, struct inode *inode);
73static void ext4_end_io_buffer_write(struct buffer_head *bh, int uptodate);
74static int __ext4_journalled_writepage(struct page *page, unsigned int len);
75static int ext4_bh_delay_or_unwritten(handle_t *handle, struct buffer_head *bh);
Alex Tomas64769242008-07-11 19:27:31 -040076
Dave Kleikampac27a0e2006-10-11 01:20:50 -070077/*
78 * Test whether an inode is a fast symlink.
79 */
Mingming Cao617ba132006-10-11 01:20:53 -070080static int ext4_inode_is_fast_symlink(struct inode *inode)
Dave Kleikampac27a0e2006-10-11 01:20:50 -070081{
Mingming Cao617ba132006-10-11 01:20:53 -070082 int ea_blocks = EXT4_I(inode)->i_file_acl ?
Dave Kleikampac27a0e2006-10-11 01:20:50 -070083 (inode->i_sb->s_blocksize >> 9) : 0;
84
85 return (S_ISLNK(inode->i_mode) && inode->i_blocks - ea_blocks == 0);
86}
87
88/*
Dave Kleikampac27a0e2006-10-11 01:20:50 -070089 * Restart the transaction associated with *handle. This does a commit,
90 * so before we call here everything must be consistently dirtied against
91 * this transaction.
92 */
Aneesh Kumar K.Vfa5d1112009-11-02 18:50:49 -050093int ext4_truncate_restart_trans(handle_t *handle, struct inode *inode,
Jan Kara487caee2009-08-17 22:17:20 -040094 int nblocks)
Dave Kleikampac27a0e2006-10-11 01:20:50 -070095{
Jan Kara487caee2009-08-17 22:17:20 -040096 int ret;
97
98 /*
Theodore Ts'oe35fd662010-05-16 19:00:00 -040099 * Drop i_data_sem to avoid deadlock with ext4_map_blocks. At this
Jan Kara487caee2009-08-17 22:17:20 -0400100 * moment, get_block can be called only for blocks inside i_size since
101 * page cache has been already dropped and writes are blocked by
102 * i_mutex. So we can safely drop the i_data_sem here.
103 */
Frank Mayhar03901312009-01-07 00:06:22 -0500104 BUG_ON(EXT4_JOURNAL(inode) == NULL);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700105 jbd_debug(2, "restarting handle %p\n", handle);
Jan Kara487caee2009-08-17 22:17:20 -0400106 up_write(&EXT4_I(inode)->i_data_sem);
Amir Goldstein8e8eaab2011-02-27 23:32:12 -0500107 ret = ext4_journal_restart(handle, nblocks);
Jan Kara487caee2009-08-17 22:17:20 -0400108 down_write(&EXT4_I(inode)->i_data_sem);
Aneesh Kumar K.Vfa5d1112009-11-02 18:50:49 -0500109 ext4_discard_preallocations(inode);
Jan Kara487caee2009-08-17 22:17:20 -0400110
111 return ret;
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700112}
113
114/*
115 * Called at the last iput() if i_nlink is zero.
116 */
Al Viro0930fcc2010-06-07 13:16:22 -0400117void ext4_evict_inode(struct inode *inode)
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700118{
119 handle_t *handle;
Theodore Ts'obc965ab2008-08-02 21:10:38 -0400120 int err;
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700121
Theodore Ts'o7ff9c072010-11-08 13:51:33 -0500122 trace_ext4_evict_inode(inode);
Jiaying Zhang2581fdc2011-08-13 12:17:13 -0400123
Jiaying Zhang2581fdc2011-08-13 12:17:13 -0400124 ext4_ioend_wait(inode);
125
Al Viro0930fcc2010-06-07 13:16:22 -0400126 if (inode->i_nlink) {
Jan Kara2d859db2011-07-26 09:07:11 -0400127 /*
128 * When journalling data dirty buffers are tracked only in the
129 * journal. So although mm thinks everything is clean and
130 * ready for reaping the inode might still have some pages to
131 * write in the running transaction or waiting to be
132 * checkpointed. Thus calling jbd2_journal_invalidatepage()
133 * (via truncate_inode_pages()) to discard these buffers can
134 * cause data loss. Also even if we did not discard these
135 * buffers, we would have no way to find them after the inode
136 * is reaped and thus user could see stale data if he tries to
137 * read them before the transaction is checkpointed. So be
138 * careful and force everything to disk here... We use
139 * ei->i_datasync_tid to store the newest transaction
140 * containing inode's data.
141 *
142 * Note that directories do not have this problem because they
143 * don't use page cache.
144 */
145 if (ext4_should_journal_data(inode) &&
146 (S_ISLNK(inode->i_mode) || S_ISREG(inode->i_mode))) {
147 journal_t *journal = EXT4_SB(inode->i_sb)->s_journal;
148 tid_t commit_tid = EXT4_I(inode)->i_datasync_tid;
149
150 jbd2_log_start_commit(journal, commit_tid);
151 jbd2_log_wait_commit(journal, commit_tid);
152 filemap_write_and_wait(&inode->i_data);
153 }
Al Viro0930fcc2010-06-07 13:16:22 -0400154 truncate_inode_pages(&inode->i_data, 0);
155 goto no_delete;
156 }
157
Christoph Hellwig907f4552010-03-03 09:05:06 -0500158 if (!is_bad_inode(inode))
Christoph Hellwig871a2932010-03-03 09:05:07 -0500159 dquot_initialize(inode);
Christoph Hellwig907f4552010-03-03 09:05:06 -0500160
Jan Kara678aaf42008-07-11 19:27:31 -0400161 if (ext4_should_order_data(inode))
162 ext4_begin_ordered_truncate(inode, 0);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700163 truncate_inode_pages(&inode->i_data, 0);
164
165 if (is_bad_inode(inode))
166 goto no_delete;
167
Theodore Ts'o9f125d62011-06-27 19:16:04 -0400168 handle = ext4_journal_start(inode, ext4_blocks_for_truncate(inode)+3);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700169 if (IS_ERR(handle)) {
Theodore Ts'obc965ab2008-08-02 21:10:38 -0400170 ext4_std_error(inode->i_sb, PTR_ERR(handle));
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700171 /*
172 * If we're going to skip the normal cleanup, we still need to
173 * make sure that the in-core orphan linked list is properly
174 * cleaned up.
175 */
Mingming Cao617ba132006-10-11 01:20:53 -0700176 ext4_orphan_del(NULL, inode);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700177 goto no_delete;
178 }
179
180 if (IS_SYNC(inode))
Frank Mayhar03901312009-01-07 00:06:22 -0500181 ext4_handle_sync(handle);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700182 inode->i_size = 0;
Theodore Ts'obc965ab2008-08-02 21:10:38 -0400183 err = ext4_mark_inode_dirty(handle, inode);
184 if (err) {
Eric Sandeen12062dd2010-02-15 14:19:27 -0500185 ext4_warning(inode->i_sb,
Theodore Ts'obc965ab2008-08-02 21:10:38 -0400186 "couldn't mark inode dirty (err %d)", err);
187 goto stop_handle;
188 }
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700189 if (inode->i_blocks)
Mingming Cao617ba132006-10-11 01:20:53 -0700190 ext4_truncate(inode);
Theodore Ts'obc965ab2008-08-02 21:10:38 -0400191
192 /*
193 * ext4_ext_truncate() doesn't reserve any slop when it
194 * restarts journal transactions; therefore there may not be
195 * enough credits left in the handle to remove the inode from
196 * the orphan list and set the dtime field.
197 */
Frank Mayhar03901312009-01-07 00:06:22 -0500198 if (!ext4_handle_has_enough_credits(handle, 3)) {
Theodore Ts'obc965ab2008-08-02 21:10:38 -0400199 err = ext4_journal_extend(handle, 3);
200 if (err > 0)
201 err = ext4_journal_restart(handle, 3);
202 if (err != 0) {
Eric Sandeen12062dd2010-02-15 14:19:27 -0500203 ext4_warning(inode->i_sb,
Theodore Ts'obc965ab2008-08-02 21:10:38 -0400204 "couldn't extend journal (err %d)", err);
205 stop_handle:
206 ext4_journal_stop(handle);
Theodore Ts'o45388212010-07-29 15:06:10 -0400207 ext4_orphan_del(NULL, inode);
Theodore Ts'obc965ab2008-08-02 21:10:38 -0400208 goto no_delete;
209 }
210 }
211
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700212 /*
Mingming Cao617ba132006-10-11 01:20:53 -0700213 * Kill off the orphan record which ext4_truncate created.
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700214 * AKPM: I think this can be inside the above `if'.
Mingming Cao617ba132006-10-11 01:20:53 -0700215 * Note that ext4_orphan_del() has to be able to cope with the
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700216 * deletion of a non-existent orphan - this is because we don't
Mingming Cao617ba132006-10-11 01:20:53 -0700217 * know if ext4_truncate() actually created an orphan record.
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700218 * (Well, we could do this if we need to, but heck - it works)
219 */
Mingming Cao617ba132006-10-11 01:20:53 -0700220 ext4_orphan_del(handle, inode);
221 EXT4_I(inode)->i_dtime = get_seconds();
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700222
223 /*
224 * One subtle ordering requirement: if anything has gone wrong
225 * (transaction abort, IO errors, whatever), then we can still
226 * do these next steps (the fs will already have been marked as
227 * having errors), but we can't free the inode if the mark_dirty
228 * fails.
229 */
Mingming Cao617ba132006-10-11 01:20:53 -0700230 if (ext4_mark_inode_dirty(handle, inode))
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700231 /* If that failed, just do the required in-core inode clear. */
Al Viro0930fcc2010-06-07 13:16:22 -0400232 ext4_clear_inode(inode);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700233 else
Mingming Cao617ba132006-10-11 01:20:53 -0700234 ext4_free_inode(handle, inode);
235 ext4_journal_stop(handle);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700236 return;
237no_delete:
Al Viro0930fcc2010-06-07 13:16:22 -0400238 ext4_clear_inode(inode); /* We must guarantee clearing of inode... */
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700239}
240
Dmitry Monakhova9e7f442009-12-14 15:21:14 +0300241#ifdef CONFIG_QUOTA
242qsize_t *ext4_get_reserved_space(struct inode *inode)
Mingming Cao60e58e02009-01-22 18:13:05 +0100243{
Dmitry Monakhova9e7f442009-12-14 15:21:14 +0300244 return &EXT4_I(inode)->i_reserved_quota;
Mingming Cao60e58e02009-01-22 18:13:05 +0100245}
Dmitry Monakhova9e7f442009-12-14 15:21:14 +0300246#endif
Theodore Ts'o9d0be502010-01-01 02:41:30 -0500247
Aneesh Kumar K.V12219ae2008-07-17 16:12:08 -0400248/*
249 * Calculate the number of metadata blocks need to reserve
Theodore Ts'o9d0be502010-01-01 02:41:30 -0500250 * to allocate a block located at @lblock
Aneesh Kumar K.V12219ae2008-07-17 16:12:08 -0400251 */
Theodore Ts'o01f49d02011-01-10 12:13:03 -0500252static int ext4_calc_metadata_amount(struct inode *inode, ext4_lblk_t lblock)
Aneesh Kumar K.V12219ae2008-07-17 16:12:08 -0400253{
Dmitry Monakhov12e9b892010-05-16 22:00:00 -0400254 if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))
Theodore Ts'o9d0be502010-01-01 02:41:30 -0500255 return ext4_ext_calc_metadata_amount(inode, lblock);
Aneesh Kumar K.V12219ae2008-07-17 16:12:08 -0400256
Amir Goldstein8bb2b242011-06-27 17:10:28 -0400257 return ext4_ind_calc_metadata_amount(inode, lblock);
Aneesh Kumar K.V12219ae2008-07-17 16:12:08 -0400258}
259
Theodore Ts'o0637c6f2009-12-30 14:20:45 -0500260/*
261 * Called with i_data_sem down, which is important since we can call
262 * ext4_discard_preallocations() from here.
263 */
Aneesh Kumar K.V5f634d02010-01-25 04:00:31 -0500264void ext4_da_update_reserve_space(struct inode *inode,
265 int used, int quota_claim)
Aneesh Kumar K.V12219ae2008-07-17 16:12:08 -0400266{
267 struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
Theodore Ts'o0637c6f2009-12-30 14:20:45 -0500268 struct ext4_inode_info *ei = EXT4_I(inode);
Aneesh Kumar K.V12219ae2008-07-17 16:12:08 -0400269
Theodore Ts'o0637c6f2009-12-30 14:20:45 -0500270 spin_lock(&ei->i_block_reservation_lock);
Theodore Ts'of8ec9d682010-01-01 01:00:21 -0500271 trace_ext4_da_update_reserve_space(inode, used);
Theodore Ts'o0637c6f2009-12-30 14:20:45 -0500272 if (unlikely(used > ei->i_reserved_data_blocks)) {
273 ext4_msg(inode->i_sb, KERN_NOTICE, "%s: ino %lu, used %d "
274 "with only %d reserved data blocks\n",
275 __func__, inode->i_ino, used,
276 ei->i_reserved_data_blocks);
277 WARN_ON(1);
278 used = ei->i_reserved_data_blocks;
Aneesh Kumar K.V6bc6e632008-10-10 09:39:00 -0400279 }
Aneesh Kumar K.V12219ae2008-07-17 16:12:08 -0400280
Theodore Ts'o0637c6f2009-12-30 14:20:45 -0500281 /* Update per-inode reservations */
282 ei->i_reserved_data_blocks -= used;
Theodore Ts'o0637c6f2009-12-30 14:20:45 -0500283 ei->i_reserved_meta_blocks -= ei->i_allocated_meta_blocks;
Eric Sandeen72b8ab92010-05-16 11:00:00 -0400284 percpu_counter_sub(&sbi->s_dirtyblocks_counter,
285 used + ei->i_allocated_meta_blocks);
Theodore Ts'o0637c6f2009-12-30 14:20:45 -0500286 ei->i_allocated_meta_blocks = 0;
Theodore Ts'o0637c6f2009-12-30 14:20:45 -0500287
288 if (ei->i_reserved_data_blocks == 0) {
289 /*
290 * We can release all of the reserved metadata blocks
291 * only when we have written all of the delayed
292 * allocation blocks.
293 */
Eric Sandeen72b8ab92010-05-16 11:00:00 -0400294 percpu_counter_sub(&sbi->s_dirtyblocks_counter,
295 ei->i_reserved_meta_blocks);
Theodore Ts'oee5f4d92010-01-01 02:36:15 -0500296 ei->i_reserved_meta_blocks = 0;
Theodore Ts'o9d0be502010-01-01 02:41:30 -0500297 ei->i_da_metadata_calc_len = 0;
Theodore Ts'o0637c6f2009-12-30 14:20:45 -0500298 }
Aneesh Kumar K.V12219ae2008-07-17 16:12:08 -0400299 spin_unlock(&EXT4_I(inode)->i_block_reservation_lock);
Mingming Cao60e58e02009-01-22 18:13:05 +0100300
Eric Sandeen72b8ab92010-05-16 11:00:00 -0400301 /* Update quota subsystem for data blocks */
302 if (quota_claim)
Christoph Hellwig5dd40562010-03-03 09:05:00 -0500303 dquot_claim_block(inode, used);
Eric Sandeen72b8ab92010-05-16 11:00:00 -0400304 else {
Aneesh Kumar K.V5f634d02010-01-25 04:00:31 -0500305 /*
306 * We did fallocate with an offset that is already delayed
307 * allocated. So on delayed allocated writeback we should
Eric Sandeen72b8ab92010-05-16 11:00:00 -0400308 * not re-claim the quota for fallocated blocks.
Aneesh Kumar K.V5f634d02010-01-25 04:00:31 -0500309 */
Eric Sandeen72b8ab92010-05-16 11:00:00 -0400310 dquot_release_reservation_block(inode, used);
Aneesh Kumar K.V5f634d02010-01-25 04:00:31 -0500311 }
Aneesh Kumar K.Vd6014302009-03-27 22:36:43 -0400312
313 /*
314 * If we have done all the pending block allocations and if
315 * there aren't any writers on the inode, we can discard the
316 * inode's preallocations.
317 */
Theodore Ts'o0637c6f2009-12-30 14:20:45 -0500318 if ((ei->i_reserved_data_blocks == 0) &&
319 (atomic_read(&inode->i_writecount) == 0))
Aneesh Kumar K.Vd6014302009-03-27 22:36:43 -0400320 ext4_discard_preallocations(inode);
Aneesh Kumar K.V12219ae2008-07-17 16:12:08 -0400321}
322
Theodore Ts'oe29136f2010-06-29 12:54:28 -0400323static int __check_block_validity(struct inode *inode, const char *func,
Theodore Ts'oc398eda2010-07-27 11:56:40 -0400324 unsigned int line,
325 struct ext4_map_blocks *map)
Theodore Ts'o6fd058f2009-05-17 15:38:01 -0400326{
Theodore Ts'o24676da2010-05-16 21:00:00 -0400327 if (!ext4_data_block_valid(EXT4_SB(inode->i_sb), map->m_pblk,
328 map->m_len)) {
Theodore Ts'oc398eda2010-07-27 11:56:40 -0400329 ext4_error_inode(inode, func, line, map->m_pblk,
330 "lblock %lu mapped to illegal pblock "
331 "(length %d)", (unsigned long) map->m_lblk,
332 map->m_len);
Theodore Ts'o6fd058f2009-05-17 15:38:01 -0400333 return -EIO;
334 }
335 return 0;
336}
337
Theodore Ts'oe29136f2010-06-29 12:54:28 -0400338#define check_block_validity(inode, map) \
Theodore Ts'oc398eda2010-07-27 11:56:40 -0400339 __check_block_validity((inode), __func__, __LINE__, (map))
Theodore Ts'oe29136f2010-06-29 12:54:28 -0400340
Mingming Caof5ab0d12008-02-25 15:29:55 -0500341/*
Theodore Ts'o1f945332009-09-30 22:57:41 -0400342 * Return the number of contiguous dirty pages in a given inode
343 * starting at page frame idx.
Theodore Ts'o55138e02009-09-29 13:31:31 -0400344 */
345static pgoff_t ext4_num_dirty_pages(struct inode *inode, pgoff_t idx,
346 unsigned int max_pages)
347{
348 struct address_space *mapping = inode->i_mapping;
349 pgoff_t index;
350 struct pagevec pvec;
351 pgoff_t num = 0;
352 int i, nr_pages, done = 0;
353
354 if (max_pages == 0)
355 return 0;
356 pagevec_init(&pvec, 0);
357 while (!done) {
358 index = idx;
359 nr_pages = pagevec_lookup_tag(&pvec, mapping, &index,
360 PAGECACHE_TAG_DIRTY,
361 (pgoff_t)PAGEVEC_SIZE);
362 if (nr_pages == 0)
363 break;
364 for (i = 0; i < nr_pages; i++) {
365 struct page *page = pvec.pages[i];
366 struct buffer_head *bh, *head;
367
368 lock_page(page);
369 if (unlikely(page->mapping != mapping) ||
370 !PageDirty(page) ||
371 PageWriteback(page) ||
372 page->index != idx) {
373 done = 1;
374 unlock_page(page);
375 break;
376 }
Theodore Ts'o1f945332009-09-30 22:57:41 -0400377 if (page_has_buffers(page)) {
378 bh = head = page_buffers(page);
379 do {
380 if (!buffer_delay(bh) &&
381 !buffer_unwritten(bh))
382 done = 1;
383 bh = bh->b_this_page;
384 } while (!done && (bh != head));
385 }
Theodore Ts'o55138e02009-09-29 13:31:31 -0400386 unlock_page(page);
387 if (done)
388 break;
389 idx++;
390 num++;
Eric Sandeen659c6002010-10-27 21:30:03 -0400391 if (num >= max_pages) {
392 done = 1;
Theodore Ts'o55138e02009-09-29 13:31:31 -0400393 break;
Eric Sandeen659c6002010-10-27 21:30:03 -0400394 }
Theodore Ts'o55138e02009-09-29 13:31:31 -0400395 }
396 pagevec_release(&pvec);
397 }
398 return num;
399}
400
401/*
Theodore Ts'oe35fd662010-05-16 19:00:00 -0400402 * The ext4_map_blocks() function tries to look up the requested blocks,
Theodore Ts'o2b2d6d02008-07-26 16:15:44 -0400403 * and returns if the blocks are already mapped.
Mingming Caof5ab0d12008-02-25 15:29:55 -0500404 *
Mingming Caof5ab0d12008-02-25 15:29:55 -0500405 * Otherwise it takes the write lock of the i_data_sem and allocate blocks
406 * and store the allocated blocks in the result buffer head and mark it
407 * mapped.
408 *
Theodore Ts'oe35fd662010-05-16 19:00:00 -0400409 * If file type is extents based, it will call ext4_ext_map_blocks(),
410 * Otherwise, call with ext4_ind_map_blocks() to handle indirect mapping
Mingming Caof5ab0d12008-02-25 15:29:55 -0500411 * based files
412 *
413 * On success, it returns the number of blocks being mapped or allocate.
414 * if create==0 and the blocks are pre-allocated and uninitialized block,
415 * the result buffer head is unmapped. If the create ==1, it will make sure
416 * the buffer head is mapped.
417 *
418 * It returns 0 if plain look up failed (blocks have not been allocated), in
419 * that casem, buffer head is unmapped
420 *
421 * It returns the error in case of allocation failure.
422 */
Theodore Ts'oe35fd662010-05-16 19:00:00 -0400423int ext4_map_blocks(handle_t *handle, struct inode *inode,
424 struct ext4_map_blocks *map, int flags)
Aneesh Kumar K.V0e855ac2008-01-28 23:58:26 -0500425{
426 int retval;
Mingming Caof5ab0d12008-02-25 15:29:55 -0500427
Theodore Ts'oe35fd662010-05-16 19:00:00 -0400428 map->m_flags = 0;
429 ext_debug("ext4_map_blocks(): inode %lu, flag %d, max_blocks %u,"
430 "logical block %lu\n", inode->i_ino, flags, map->m_len,
431 (unsigned long) map->m_lblk);
Aneesh Kumar K.V4df3d262008-01-28 23:58:29 -0500432 /*
Theodore Ts'ob920c752009-05-14 00:54:29 -0400433 * Try to see if we can get the block without requesting a new
434 * file system block.
Aneesh Kumar K.V4df3d262008-01-28 23:58:29 -0500435 */
436 down_read((&EXT4_I(inode)->i_data_sem));
Dmitry Monakhov12e9b892010-05-16 22:00:00 -0400437 if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)) {
Theodore Ts'oe35fd662010-05-16 19:00:00 -0400438 retval = ext4_ext_map_blocks(handle, inode, map, 0);
Aneesh Kumar K.V0e855ac2008-01-28 23:58:26 -0500439 } else {
Theodore Ts'oe35fd662010-05-16 19:00:00 -0400440 retval = ext4_ind_map_blocks(handle, inode, map, 0);
Aneesh Kumar K.V0e855ac2008-01-28 23:58:26 -0500441 }
Aneesh Kumar K.V4df3d262008-01-28 23:58:29 -0500442 up_read((&EXT4_I(inode)->i_data_sem));
Mingming Caof5ab0d12008-02-25 15:29:55 -0500443
Theodore Ts'oe35fd662010-05-16 19:00:00 -0400444 if (retval > 0 && map->m_flags & EXT4_MAP_MAPPED) {
Theodore Ts'oe29136f2010-06-29 12:54:28 -0400445 int ret = check_block_validity(inode, map);
Theodore Ts'o6fd058f2009-05-17 15:38:01 -0400446 if (ret != 0)
447 return ret;
448 }
449
Mingming Caof5ab0d12008-02-25 15:29:55 -0500450 /* If it is only a block(s) look up */
Theodore Ts'oc2177052009-05-14 00:58:52 -0400451 if ((flags & EXT4_GET_BLOCKS_CREATE) == 0)
Aneesh Kumar K.V4df3d262008-01-28 23:58:29 -0500452 return retval;
453
454 /*
Mingming Caof5ab0d12008-02-25 15:29:55 -0500455 * Returns if the blocks have already allocated
456 *
457 * Note that if blocks have been preallocated
458 * ext4_ext_get_block() returns th create = 0
459 * with buffer head unmapped.
460 */
Theodore Ts'oe35fd662010-05-16 19:00:00 -0400461 if (retval > 0 && map->m_flags & EXT4_MAP_MAPPED)
Mingming Caof5ab0d12008-02-25 15:29:55 -0500462 return retval;
463
464 /*
Aneesh Kumar K.V2a8964d2009-05-14 17:05:39 -0400465 * When we call get_blocks without the create flag, the
466 * BH_Unwritten flag could have gotten set if the blocks
467 * requested were part of a uninitialized extent. We need to
468 * clear this flag now that we are committed to convert all or
469 * part of the uninitialized extent to be an initialized
470 * extent. This is because we need to avoid the combination
471 * of BH_Unwritten and BH_Mapped flags being simultaneously
472 * set on the buffer_head.
473 */
Theodore Ts'oe35fd662010-05-16 19:00:00 -0400474 map->m_flags &= ~EXT4_MAP_UNWRITTEN;
Aneesh Kumar K.V2a8964d2009-05-14 17:05:39 -0400475
476 /*
Mingming Caof5ab0d12008-02-25 15:29:55 -0500477 * New blocks allocate and/or writing to uninitialized extent
478 * will possibly result in updating i_data, so we take
479 * the write lock of i_data_sem, and call get_blocks()
480 * with create == 1 flag.
Aneesh Kumar K.V4df3d262008-01-28 23:58:29 -0500481 */
482 down_write((&EXT4_I(inode)->i_data_sem));
Mingming Caod2a17632008-07-14 17:52:37 -0400483
484 /*
485 * if the caller is from delayed allocation writeout path
486 * we have already reserved fs blocks for allocation
487 * let the underlying get_block() function know to
488 * avoid double accounting
489 */
Theodore Ts'oc2177052009-05-14 00:58:52 -0400490 if (flags & EXT4_GET_BLOCKS_DELALLOC_RESERVE)
Theodore Ts'of2321092011-01-10 12:12:36 -0500491 ext4_set_inode_state(inode, EXT4_STATE_DELALLOC_RESERVED);
Aneesh Kumar K.V4df3d262008-01-28 23:58:29 -0500492 /*
493 * We need to check for EXT4 here because migrate
494 * could have changed the inode type in between
495 */
Dmitry Monakhov12e9b892010-05-16 22:00:00 -0400496 if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)) {
Theodore Ts'oe35fd662010-05-16 19:00:00 -0400497 retval = ext4_ext_map_blocks(handle, inode, map, flags);
Aneesh Kumar K.V0e855ac2008-01-28 23:58:26 -0500498 } else {
Theodore Ts'oe35fd662010-05-16 19:00:00 -0400499 retval = ext4_ind_map_blocks(handle, inode, map, flags);
Aneesh Kumar K.V267e4db2008-04-29 08:11:12 -0400500
Theodore Ts'oe35fd662010-05-16 19:00:00 -0400501 if (retval > 0 && map->m_flags & EXT4_MAP_NEW) {
Aneesh Kumar K.V267e4db2008-04-29 08:11:12 -0400502 /*
503 * We allocated new blocks which will result in
504 * i_data's format changing. Force the migrate
505 * to fail by clearing migrate flags
506 */
Theodore Ts'o19f5fb72010-01-24 14:34:07 -0500507 ext4_clear_inode_state(inode, EXT4_STATE_EXT_MIGRATE);
Aneesh Kumar K.V267e4db2008-04-29 08:11:12 -0400508 }
Mingming Caod2a17632008-07-14 17:52:37 -0400509
Aneesh Kumar K.V5f634d02010-01-25 04:00:31 -0500510 /*
511 * Update reserved blocks/metadata blocks after successful
512 * block allocation which had been deferred till now. We don't
513 * support fallocate for non extent files. So we can update
514 * reserve space here.
515 */
516 if ((retval > 0) &&
Aneesh Kumar K.V1296cc82010-01-15 01:27:59 -0500517 (flags & EXT4_GET_BLOCKS_DELALLOC_RESERVE))
Aneesh Kumar K.V5f634d02010-01-25 04:00:31 -0500518 ext4_da_update_reserve_space(inode, retval, 1);
519 }
Theodore Ts'o2ac3b6e2009-05-14 13:57:08 -0400520 if (flags & EXT4_GET_BLOCKS_DELALLOC_RESERVE)
Theodore Ts'of2321092011-01-10 12:12:36 -0500521 ext4_clear_inode_state(inode, EXT4_STATE_DELALLOC_RESERVED);
Theodore Ts'o2ac3b6e2009-05-14 13:57:08 -0400522
Aneesh Kumar K.V4df3d262008-01-28 23:58:29 -0500523 up_write((&EXT4_I(inode)->i_data_sem));
Theodore Ts'oe35fd662010-05-16 19:00:00 -0400524 if (retval > 0 && map->m_flags & EXT4_MAP_MAPPED) {
Theodore Ts'oe29136f2010-06-29 12:54:28 -0400525 int ret = check_block_validity(inode, map);
Theodore Ts'o6fd058f2009-05-17 15:38:01 -0400526 if (ret != 0)
527 return ret;
528 }
Aneesh Kumar K.V0e855ac2008-01-28 23:58:26 -0500529 return retval;
530}
531
Mingming Caof3bd1f32008-08-19 22:16:03 -0400532/* Maximum number of blocks we map for direct IO at once. */
533#define DIO_MAX_BLOCKS 4096
534
Theodore Ts'o2ed88682010-05-16 20:00:00 -0400535static int _ext4_get_block(struct inode *inode, sector_t iblock,
536 struct buffer_head *bh, int flags)
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700537{
Dmitriy Monakhov3e4fdaf2007-02-10 01:46:35 -0800538 handle_t *handle = ext4_journal_current_handle();
Theodore Ts'o2ed88682010-05-16 20:00:00 -0400539 struct ext4_map_blocks map;
Jan Kara7fb54092008-02-10 01:08:38 -0500540 int ret = 0, started = 0;
Mingming Caof3bd1f32008-08-19 22:16:03 -0400541 int dio_credits;
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700542
Theodore Ts'o2ed88682010-05-16 20:00:00 -0400543 map.m_lblk = iblock;
544 map.m_len = bh->b_size >> inode->i_blkbits;
545
546 if (flags && !handle) {
Jan Kara7fb54092008-02-10 01:08:38 -0500547 /* Direct IO write... */
Theodore Ts'o2ed88682010-05-16 20:00:00 -0400548 if (map.m_len > DIO_MAX_BLOCKS)
549 map.m_len = DIO_MAX_BLOCKS;
550 dio_credits = ext4_chunk_trans_blocks(inode, map.m_len);
Mingming Caof3bd1f32008-08-19 22:16:03 -0400551 handle = ext4_journal_start(inode, dio_credits);
Jan Kara7fb54092008-02-10 01:08:38 -0500552 if (IS_ERR(handle)) {
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700553 ret = PTR_ERR(handle);
Theodore Ts'o2ed88682010-05-16 20:00:00 -0400554 return ret;
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700555 }
Jan Kara7fb54092008-02-10 01:08:38 -0500556 started = 1;
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700557 }
558
Theodore Ts'o2ed88682010-05-16 20:00:00 -0400559 ret = ext4_map_blocks(handle, inode, &map, flags);
Jan Kara7fb54092008-02-10 01:08:38 -0500560 if (ret > 0) {
Theodore Ts'o2ed88682010-05-16 20:00:00 -0400561 map_bh(bh, inode->i_sb, map.m_pblk);
562 bh->b_state = (bh->b_state & ~EXT4_MAP_FLAGS) | map.m_flags;
563 bh->b_size = inode->i_sb->s_blocksize * map.m_len;
Jan Kara7fb54092008-02-10 01:08:38 -0500564 ret = 0;
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700565 }
Jan Kara7fb54092008-02-10 01:08:38 -0500566 if (started)
567 ext4_journal_stop(handle);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700568 return ret;
569}
570
Theodore Ts'o2ed88682010-05-16 20:00:00 -0400571int ext4_get_block(struct inode *inode, sector_t iblock,
572 struct buffer_head *bh, int create)
573{
574 return _ext4_get_block(inode, iblock, bh,
575 create ? EXT4_GET_BLOCKS_CREATE : 0);
576}
577
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700578/*
579 * `handle' can be NULL if create is zero
580 */
Mingming Cao617ba132006-10-11 01:20:53 -0700581struct buffer_head *ext4_getblk(handle_t *handle, struct inode *inode,
Aneesh Kumar K.V725d26d2008-01-28 23:58:27 -0500582 ext4_lblk_t block, int create, int *errp)
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700583{
Theodore Ts'o2ed88682010-05-16 20:00:00 -0400584 struct ext4_map_blocks map;
585 struct buffer_head *bh;
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700586 int fatal = 0, err;
587
588 J_ASSERT(handle != NULL || create == 0);
589
Theodore Ts'o2ed88682010-05-16 20:00:00 -0400590 map.m_lblk = block;
591 map.m_len = 1;
592 err = ext4_map_blocks(handle, inode, &map,
593 create ? EXT4_GET_BLOCKS_CREATE : 0);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700594
Theodore Ts'o2ed88682010-05-16 20:00:00 -0400595 if (err < 0)
596 *errp = err;
597 if (err <= 0)
598 return NULL;
599 *errp = 0;
600
601 bh = sb_getblk(inode->i_sb, map.m_pblk);
602 if (!bh) {
603 *errp = -EIO;
604 return NULL;
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700605 }
Theodore Ts'o2ed88682010-05-16 20:00:00 -0400606 if (map.m_flags & EXT4_MAP_NEW) {
607 J_ASSERT(create != 0);
608 J_ASSERT(handle != NULL);
609
610 /*
611 * Now that we do not always journal data, we should
612 * keep in mind whether this should always journal the
613 * new buffer as metadata. For now, regular file
614 * writes use ext4_get_block instead, so it's not a
615 * problem.
616 */
617 lock_buffer(bh);
618 BUFFER_TRACE(bh, "call get_create_access");
619 fatal = ext4_journal_get_create_access(handle, bh);
620 if (!fatal && !buffer_uptodate(bh)) {
621 memset(bh->b_data, 0, inode->i_sb->s_blocksize);
622 set_buffer_uptodate(bh);
623 }
624 unlock_buffer(bh);
625 BUFFER_TRACE(bh, "call ext4_handle_dirty_metadata");
626 err = ext4_handle_dirty_metadata(handle, inode, bh);
627 if (!fatal)
628 fatal = err;
629 } else {
630 BUFFER_TRACE(bh, "not a new buffer");
631 }
632 if (fatal) {
633 *errp = fatal;
634 brelse(bh);
635 bh = NULL;
636 }
637 return bh;
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700638}
639
Mingming Cao617ba132006-10-11 01:20:53 -0700640struct buffer_head *ext4_bread(handle_t *handle, struct inode *inode,
Aneesh Kumar K.V725d26d2008-01-28 23:58:27 -0500641 ext4_lblk_t block, int create, int *err)
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700642{
Theodore Ts'oaf5bc922008-09-08 22:25:24 -0400643 struct buffer_head *bh;
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700644
Mingming Cao617ba132006-10-11 01:20:53 -0700645 bh = ext4_getblk(handle, inode, block, create, err);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700646 if (!bh)
647 return bh;
648 if (buffer_uptodate(bh))
649 return bh;
Christoph Hellwig65299a32011-08-23 14:50:29 +0200650 ll_rw_block(READ | REQ_META | REQ_PRIO, 1, &bh);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700651 wait_on_buffer(bh);
652 if (buffer_uptodate(bh))
653 return bh;
654 put_bh(bh);
655 *err = -EIO;
656 return NULL;
657}
658
Theodore Ts'oaf5bc922008-09-08 22:25:24 -0400659static int walk_page_buffers(handle_t *handle,
660 struct buffer_head *head,
661 unsigned from,
662 unsigned to,
663 int *partial,
664 int (*fn)(handle_t *handle,
665 struct buffer_head *bh))
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700666{
667 struct buffer_head *bh;
668 unsigned block_start, block_end;
669 unsigned blocksize = head->b_size;
670 int err, ret = 0;
671 struct buffer_head *next;
672
Theodore Ts'oaf5bc922008-09-08 22:25:24 -0400673 for (bh = head, block_start = 0;
674 ret == 0 && (bh != head || !block_start);
Theodore Ts'ode9a55b2009-06-14 17:45:34 -0400675 block_start = block_end, bh = next) {
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700676 next = bh->b_this_page;
677 block_end = block_start + blocksize;
678 if (block_end <= from || block_start >= to) {
679 if (partial && !buffer_uptodate(bh))
680 *partial = 1;
681 continue;
682 }
683 err = (*fn)(handle, bh);
684 if (!ret)
685 ret = err;
686 }
687 return ret;
688}
689
690/*
691 * To preserve ordering, it is essential that the hole instantiation and
692 * the data write be encapsulated in a single transaction. We cannot
Mingming Cao617ba132006-10-11 01:20:53 -0700693 * close off a transaction and start a new one between the ext4_get_block()
Mingming Caodab291a2006-10-11 01:21:01 -0700694 * and the commit_write(). So doing the jbd2_journal_start at the start of
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700695 * prepare_write() is the right place.
696 *
Mingming Cao617ba132006-10-11 01:20:53 -0700697 * Also, this function can nest inside ext4_writepage() ->
698 * block_write_full_page(). In that case, we *know* that ext4_writepage()
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700699 * has generated enough buffer credits to do the whole page. So we won't
700 * block on the journal in that case, which is good, because the caller may
701 * be PF_MEMALLOC.
702 *
Mingming Cao617ba132006-10-11 01:20:53 -0700703 * By accident, ext4 can be reentered when a transaction is open via
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700704 * quota file writes. If we were to commit the transaction while thus
705 * reentered, there can be a deadlock - we would be holding a quota
706 * lock, and the commit would never complete if another thread had a
707 * transaction open and was blocking on the quota lock - a ranking
708 * violation.
709 *
Mingming Caodab291a2006-10-11 01:21:01 -0700710 * So what we do is to rely on the fact that jbd2_journal_stop/journal_start
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700711 * will _not_ run commit under these circumstances because handle->h_ref
712 * is elevated. We'll still have enough credits for the tiny quotafile
713 * write.
714 */
715static int do_journal_get_write_access(handle_t *handle,
Theodore Ts'ode9a55b2009-06-14 17:45:34 -0400716 struct buffer_head *bh)
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700717{
Jan Kara56d35a42010-08-05 14:41:42 -0400718 int dirty = buffer_dirty(bh);
719 int ret;
720
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700721 if (!buffer_mapped(bh) || buffer_freed(bh))
722 return 0;
Jan Kara56d35a42010-08-05 14:41:42 -0400723 /*
Christoph Hellwigebdec242010-10-06 10:47:23 +0200724 * __block_write_begin() could have dirtied some buffers. Clean
Jan Kara56d35a42010-08-05 14:41:42 -0400725 * the dirty bit as jbd2_journal_get_write_access() could complain
726 * otherwise about fs integrity issues. Setting of the dirty bit
Christoph Hellwigebdec242010-10-06 10:47:23 +0200727 * by __block_write_begin() isn't a real problem here as we clear
Jan Kara56d35a42010-08-05 14:41:42 -0400728 * the bit before releasing a page lock and thus writeback cannot
729 * ever write the buffer.
730 */
731 if (dirty)
732 clear_buffer_dirty(bh);
733 ret = ext4_journal_get_write_access(handle, bh);
734 if (!ret && dirty)
735 ret = ext4_handle_dirty_metadata(handle, NULL, bh);
736 return ret;
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700737}
738
Jiaying Zhang744692d2010-03-04 16:14:02 -0500739static int ext4_get_block_write(struct inode *inode, sector_t iblock,
740 struct buffer_head *bh_result, int create);
Nick Pigginbfc1af62007-10-16 01:25:05 -0700741static int ext4_write_begin(struct file *file, struct address_space *mapping,
Theodore Ts'ode9a55b2009-06-14 17:45:34 -0400742 loff_t pos, unsigned len, unsigned flags,
743 struct page **pagep, void **fsdata)
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700744{
Theodore Ts'oaf5bc922008-09-08 22:25:24 -0400745 struct inode *inode = mapping->host;
Aneesh Kumar K.V1938a152009-06-05 01:00:26 -0400746 int ret, needed_blocks;
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700747 handle_t *handle;
748 int retries = 0;
Theodore Ts'oaf5bc922008-09-08 22:25:24 -0400749 struct page *page;
Theodore Ts'ode9a55b2009-06-14 17:45:34 -0400750 pgoff_t index;
Theodore Ts'oaf5bc922008-09-08 22:25:24 -0400751 unsigned from, to;
Nick Pigginbfc1af62007-10-16 01:25:05 -0700752
Theodore Ts'o9bffad12009-06-17 11:48:11 -0400753 trace_ext4_write_begin(inode, pos, len, flags);
Aneesh Kumar K.V1938a152009-06-05 01:00:26 -0400754 /*
755 * Reserve one block more for addition to orphan list in case
756 * we allocate blocks but write fails for some reason
757 */
758 needed_blocks = ext4_writepage_trans_blocks(inode) + 1;
Theodore Ts'ode9a55b2009-06-14 17:45:34 -0400759 index = pos >> PAGE_CACHE_SHIFT;
Theodore Ts'oaf5bc922008-09-08 22:25:24 -0400760 from = pos & (PAGE_CACHE_SIZE - 1);
761 to = from + len;
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700762
763retry:
Theodore Ts'oaf5bc922008-09-08 22:25:24 -0400764 handle = ext4_journal_start(inode, needed_blocks);
765 if (IS_ERR(handle)) {
766 ret = PTR_ERR(handle);
767 goto out;
Nick Pigginbfc1af62007-10-16 01:25:05 -0700768 }
769
Jan Karaebd36102009-02-22 21:09:59 -0500770 /* We cannot recurse into the filesystem as the transaction is already
771 * started */
772 flags |= AOP_FLAG_NOFS;
773
Nick Piggin54566b22009-01-04 12:00:53 -0800774 page = grab_cache_page_write_begin(mapping, index, flags);
Jan Karacf108bc2008-07-11 19:27:31 -0400775 if (!page) {
776 ext4_journal_stop(handle);
777 ret = -ENOMEM;
778 goto out;
779 }
780 *pagep = page;
781
Jiaying Zhang744692d2010-03-04 16:14:02 -0500782 if (ext4_should_dioread_nolock(inode))
Christoph Hellwig6e1db882010-06-04 11:29:57 +0200783 ret = __block_write_begin(page, pos, len, ext4_get_block_write);
Jiaying Zhang744692d2010-03-04 16:14:02 -0500784 else
Christoph Hellwig6e1db882010-06-04 11:29:57 +0200785 ret = __block_write_begin(page, pos, len, ext4_get_block);
Nick Pigginbfc1af62007-10-16 01:25:05 -0700786
787 if (!ret && ext4_should_journal_data(inode)) {
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700788 ret = walk_page_buffers(handle, page_buffers(page),
789 from, to, NULL, do_journal_get_write_access);
790 }
Nick Pigginbfc1af62007-10-16 01:25:05 -0700791
792 if (ret) {
Theodore Ts'oaf5bc922008-09-08 22:25:24 -0400793 unlock_page(page);
Theodore Ts'oaf5bc922008-09-08 22:25:24 -0400794 page_cache_release(page);
Aneesh Kumar K.Vae4d5372008-09-13 13:10:25 -0400795 /*
Christoph Hellwig6e1db882010-06-04 11:29:57 +0200796 * __block_write_begin may have instantiated a few blocks
Aneesh Kumar K.Vae4d5372008-09-13 13:10:25 -0400797 * outside i_size. Trim these off again. Don't need
798 * i_size_read because we hold i_mutex.
Aneesh Kumar K.V1938a152009-06-05 01:00:26 -0400799 *
800 * Add inode to orphan list in case we crash before
801 * truncate finishes
Aneesh Kumar K.Vae4d5372008-09-13 13:10:25 -0400802 */
Jan Karaffacfa72009-07-13 16:22:22 -0400803 if (pos + len > inode->i_size && ext4_can_truncate(inode))
Aneesh Kumar K.V1938a152009-06-05 01:00:26 -0400804 ext4_orphan_add(handle, inode);
805
806 ext4_journal_stop(handle);
807 if (pos + len > inode->i_size) {
Jan Karab9a42072009-12-08 21:24:33 -0500808 ext4_truncate_failed_write(inode);
Theodore Ts'ode9a55b2009-06-14 17:45:34 -0400809 /*
Jan Karaffacfa72009-07-13 16:22:22 -0400810 * If truncate failed early the inode might
Aneesh Kumar K.V1938a152009-06-05 01:00:26 -0400811 * still be on the orphan list; we need to
812 * make sure the inode is removed from the
813 * orphan list in that case.
814 */
815 if (inode->i_nlink)
816 ext4_orphan_del(NULL, inode);
817 }
Nick Pigginbfc1af62007-10-16 01:25:05 -0700818 }
819
Mingming Cao617ba132006-10-11 01:20:53 -0700820 if (ret == -ENOSPC && ext4_should_retry_alloc(inode->i_sb, &retries))
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700821 goto retry;
Andrew Morton7479d2b2007-04-01 23:49:44 -0700822out:
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700823 return ret;
824}
825
Nick Pigginbfc1af62007-10-16 01:25:05 -0700826/* For write_end() in data=journal mode */
827static int write_end_fn(handle_t *handle, struct buffer_head *bh)
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700828{
829 if (!buffer_mapped(bh) || buffer_freed(bh))
830 return 0;
831 set_buffer_uptodate(bh);
Frank Mayhar03901312009-01-07 00:06:22 -0500832 return ext4_handle_dirty_metadata(handle, NULL, bh);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700833}
834
Aneesh Kumar K.Vf8514082009-06-05 00:56:49 -0400835static int ext4_generic_write_end(struct file *file,
Theodore Ts'ode9a55b2009-06-14 17:45:34 -0400836 struct address_space *mapping,
837 loff_t pos, unsigned len, unsigned copied,
838 struct page *page, void *fsdata)
Aneesh Kumar K.Vf8514082009-06-05 00:56:49 -0400839{
840 int i_size_changed = 0;
841 struct inode *inode = mapping->host;
842 handle_t *handle = ext4_journal_current_handle();
843
844 copied = block_write_end(file, mapping, pos, len, copied, page, fsdata);
845
846 /*
847 * No need to use i_size_read() here, the i_size
848 * cannot change under us because we hold i_mutex.
849 *
850 * But it's important to update i_size while still holding page lock:
851 * page writeout could otherwise come in and zero beyond i_size.
852 */
853 if (pos + copied > inode->i_size) {
854 i_size_write(inode, pos + copied);
855 i_size_changed = 1;
856 }
857
858 if (pos + copied > EXT4_I(inode)->i_disksize) {
859 /* We need to mark inode dirty even if
860 * new_i_size is less that inode->i_size
861 * bu greater than i_disksize.(hint delalloc)
862 */
863 ext4_update_i_disksize(inode, (pos + copied));
864 i_size_changed = 1;
865 }
866 unlock_page(page);
867 page_cache_release(page);
868
869 /*
870 * Don't mark the inode dirty under page lock. First, it unnecessarily
871 * makes the holding time of page lock longer. Second, it forces lock
872 * ordering of page lock and transaction start for journaling
873 * filesystems.
874 */
875 if (i_size_changed)
876 ext4_mark_inode_dirty(handle, inode);
877
878 return copied;
879}
880
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700881/*
882 * We need to pick up the new inode size which generic_commit_write gave us
883 * `file' can be NULL - eg, when called from page_symlink().
884 *
Mingming Cao617ba132006-10-11 01:20:53 -0700885 * ext4 never places buffers on inode->i_mapping->private_list. metadata
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700886 * buffers are managed internally.
887 */
Nick Pigginbfc1af62007-10-16 01:25:05 -0700888static int ext4_ordered_write_end(struct file *file,
Theodore Ts'ode9a55b2009-06-14 17:45:34 -0400889 struct address_space *mapping,
890 loff_t pos, unsigned len, unsigned copied,
891 struct page *page, void *fsdata)
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700892{
Mingming Cao617ba132006-10-11 01:20:53 -0700893 handle_t *handle = ext4_journal_current_handle();
Jan Karacf108bc2008-07-11 19:27:31 -0400894 struct inode *inode = mapping->host;
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700895 int ret = 0, ret2;
896
Theodore Ts'o9bffad12009-06-17 11:48:11 -0400897 trace_ext4_ordered_write_end(inode, pos, len, copied);
Jan Kara678aaf42008-07-11 19:27:31 -0400898 ret = ext4_jbd2_file_inode(handle, inode);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700899
900 if (ret == 0) {
Aneesh Kumar K.Vf8514082009-06-05 00:56:49 -0400901 ret2 = ext4_generic_write_end(file, mapping, pos, len, copied,
Nick Pigginbfc1af62007-10-16 01:25:05 -0700902 page, fsdata);
Roel Kluinf8a87d82008-04-29 22:01:18 -0400903 copied = ret2;
Jan Karaffacfa72009-07-13 16:22:22 -0400904 if (pos + len > inode->i_size && ext4_can_truncate(inode))
Aneesh Kumar K.Vf8514082009-06-05 00:56:49 -0400905 /* if we have allocated more blocks and copied
906 * less. We will have blocks allocated outside
907 * inode->i_size. So truncate them
908 */
909 ext4_orphan_add(handle, inode);
Roel Kluinf8a87d82008-04-29 22:01:18 -0400910 if (ret2 < 0)
911 ret = ret2;
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700912 }
Mingming Cao617ba132006-10-11 01:20:53 -0700913 ret2 = ext4_journal_stop(handle);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700914 if (!ret)
915 ret = ret2;
Nick Pigginbfc1af62007-10-16 01:25:05 -0700916
Aneesh Kumar K.Vf8514082009-06-05 00:56:49 -0400917 if (pos + len > inode->i_size) {
Jan Karab9a42072009-12-08 21:24:33 -0500918 ext4_truncate_failed_write(inode);
Theodore Ts'ode9a55b2009-06-14 17:45:34 -0400919 /*
Jan Karaffacfa72009-07-13 16:22:22 -0400920 * If truncate failed early the inode might still be
Aneesh Kumar K.Vf8514082009-06-05 00:56:49 -0400921 * on the orphan list; we need to make sure the inode
922 * is removed from the orphan list in that case.
923 */
924 if (inode->i_nlink)
925 ext4_orphan_del(NULL, inode);
926 }
927
928
Nick Pigginbfc1af62007-10-16 01:25:05 -0700929 return ret ? ret : copied;
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700930}
931
Nick Pigginbfc1af62007-10-16 01:25:05 -0700932static int ext4_writeback_write_end(struct file *file,
Theodore Ts'ode9a55b2009-06-14 17:45:34 -0400933 struct address_space *mapping,
934 loff_t pos, unsigned len, unsigned copied,
935 struct page *page, void *fsdata)
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700936{
Mingming Cao617ba132006-10-11 01:20:53 -0700937 handle_t *handle = ext4_journal_current_handle();
Jan Karacf108bc2008-07-11 19:27:31 -0400938 struct inode *inode = mapping->host;
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700939 int ret = 0, ret2;
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700940
Theodore Ts'o9bffad12009-06-17 11:48:11 -0400941 trace_ext4_writeback_write_end(inode, pos, len, copied);
Aneesh Kumar K.Vf8514082009-06-05 00:56:49 -0400942 ret2 = ext4_generic_write_end(file, mapping, pos, len, copied,
Nick Pigginbfc1af62007-10-16 01:25:05 -0700943 page, fsdata);
Roel Kluinf8a87d82008-04-29 22:01:18 -0400944 copied = ret2;
Jan Karaffacfa72009-07-13 16:22:22 -0400945 if (pos + len > inode->i_size && ext4_can_truncate(inode))
Aneesh Kumar K.Vf8514082009-06-05 00:56:49 -0400946 /* if we have allocated more blocks and copied
947 * less. We will have blocks allocated outside
948 * inode->i_size. So truncate them
949 */
950 ext4_orphan_add(handle, inode);
951
Roel Kluinf8a87d82008-04-29 22:01:18 -0400952 if (ret2 < 0)
953 ret = ret2;
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700954
Mingming Cao617ba132006-10-11 01:20:53 -0700955 ret2 = ext4_journal_stop(handle);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700956 if (!ret)
957 ret = ret2;
Nick Pigginbfc1af62007-10-16 01:25:05 -0700958
Aneesh Kumar K.Vf8514082009-06-05 00:56:49 -0400959 if (pos + len > inode->i_size) {
Jan Karab9a42072009-12-08 21:24:33 -0500960 ext4_truncate_failed_write(inode);
Theodore Ts'ode9a55b2009-06-14 17:45:34 -0400961 /*
Jan Karaffacfa72009-07-13 16:22:22 -0400962 * If truncate failed early the inode might still be
Aneesh Kumar K.Vf8514082009-06-05 00:56:49 -0400963 * on the orphan list; we need to make sure the inode
964 * is removed from the orphan list in that case.
965 */
966 if (inode->i_nlink)
967 ext4_orphan_del(NULL, inode);
968 }
969
Nick Pigginbfc1af62007-10-16 01:25:05 -0700970 return ret ? ret : copied;
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700971}
972
Nick Pigginbfc1af62007-10-16 01:25:05 -0700973static int ext4_journalled_write_end(struct file *file,
Theodore Ts'ode9a55b2009-06-14 17:45:34 -0400974 struct address_space *mapping,
975 loff_t pos, unsigned len, unsigned copied,
976 struct page *page, void *fsdata)
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700977{
Mingming Cao617ba132006-10-11 01:20:53 -0700978 handle_t *handle = ext4_journal_current_handle();
Nick Pigginbfc1af62007-10-16 01:25:05 -0700979 struct inode *inode = mapping->host;
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700980 int ret = 0, ret2;
981 int partial = 0;
Nick Pigginbfc1af62007-10-16 01:25:05 -0700982 unsigned from, to;
Aneesh Kumar K.Vcf17fea2008-09-13 13:06:18 -0400983 loff_t new_i_size;
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700984
Theodore Ts'o9bffad12009-06-17 11:48:11 -0400985 trace_ext4_journalled_write_end(inode, pos, len, copied);
Nick Pigginbfc1af62007-10-16 01:25:05 -0700986 from = pos & (PAGE_CACHE_SIZE - 1);
987 to = from + len;
988
Curt Wohlgemuth441c8502011-08-13 11:25:18 -0400989 BUG_ON(!ext4_handle_valid(handle));
990
Nick Pigginbfc1af62007-10-16 01:25:05 -0700991 if (copied < len) {
992 if (!PageUptodate(page))
993 copied = 0;
994 page_zero_new_buffers(page, from+copied, to);
995 }
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700996
997 ret = walk_page_buffers(handle, page_buffers(page), from,
Nick Pigginbfc1af62007-10-16 01:25:05 -0700998 to, &partial, write_end_fn);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700999 if (!partial)
1000 SetPageUptodate(page);
Aneesh Kumar K.Vcf17fea2008-09-13 13:06:18 -04001001 new_i_size = pos + copied;
1002 if (new_i_size > inode->i_size)
Nick Pigginbfc1af62007-10-16 01:25:05 -07001003 i_size_write(inode, pos+copied);
Theodore Ts'o19f5fb72010-01-24 14:34:07 -05001004 ext4_set_inode_state(inode, EXT4_STATE_JDATA);
Jan Kara2d859db2011-07-26 09:07:11 -04001005 EXT4_I(inode)->i_datasync_tid = handle->h_transaction->t_tid;
Aneesh Kumar K.Vcf17fea2008-09-13 13:06:18 -04001006 if (new_i_size > EXT4_I(inode)->i_disksize) {
1007 ext4_update_i_disksize(inode, new_i_size);
Mingming Cao617ba132006-10-11 01:20:53 -07001008 ret2 = ext4_mark_inode_dirty(handle, inode);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001009 if (!ret)
1010 ret = ret2;
1011 }
Nick Pigginbfc1af62007-10-16 01:25:05 -07001012
Jan Karacf108bc2008-07-11 19:27:31 -04001013 unlock_page(page);
Aneesh Kumar K.Vf8514082009-06-05 00:56:49 -04001014 page_cache_release(page);
Jan Karaffacfa72009-07-13 16:22:22 -04001015 if (pos + len > inode->i_size && ext4_can_truncate(inode))
Aneesh Kumar K.Vf8514082009-06-05 00:56:49 -04001016 /* if we have allocated more blocks and copied
1017 * less. We will have blocks allocated outside
1018 * inode->i_size. So truncate them
1019 */
1020 ext4_orphan_add(handle, inode);
1021
Mingming Cao617ba132006-10-11 01:20:53 -07001022 ret2 = ext4_journal_stop(handle);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001023 if (!ret)
1024 ret = ret2;
Aneesh Kumar K.Vf8514082009-06-05 00:56:49 -04001025 if (pos + len > inode->i_size) {
Jan Karab9a42072009-12-08 21:24:33 -05001026 ext4_truncate_failed_write(inode);
Theodore Ts'ode9a55b2009-06-14 17:45:34 -04001027 /*
Jan Karaffacfa72009-07-13 16:22:22 -04001028 * If truncate failed early the inode might still be
Aneesh Kumar K.Vf8514082009-06-05 00:56:49 -04001029 * on the orphan list; we need to make sure the inode
1030 * is removed from the orphan list in that case.
1031 */
1032 if (inode->i_nlink)
1033 ext4_orphan_del(NULL, inode);
1034 }
Nick Pigginbfc1af62007-10-16 01:25:05 -07001035
1036 return ret ? ret : copied;
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001037}
Mingming Caod2a17632008-07-14 17:52:37 -04001038
Theodore Ts'o9d0be502010-01-01 02:41:30 -05001039/*
1040 * Reserve a single block located at lblock
1041 */
Theodore Ts'o01f49d02011-01-10 12:13:03 -05001042static int ext4_da_reserve_space(struct inode *inode, ext4_lblk_t lblock)
Mingming Caod2a17632008-07-14 17:52:37 -04001043{
Aneesh Kumar K.V030ba6b2008-09-08 23:14:50 -04001044 int retries = 0;
Mingming Cao60e58e02009-01-22 18:13:05 +01001045 struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
Theodore Ts'o0637c6f2009-12-30 14:20:45 -05001046 struct ext4_inode_info *ei = EXT4_I(inode);
Eric Sandeen72b8ab92010-05-16 11:00:00 -04001047 unsigned long md_needed;
Christoph Hellwig5dd40562010-03-03 09:05:00 -05001048 int ret;
Mingming Caod2a17632008-07-14 17:52:37 -04001049
1050 /*
1051 * recalculate the amount of metadata blocks to reserve
1052 * in order to allocate nrblocks
1053 * worse case is one extent per block
1054 */
Aneesh Kumar K.V030ba6b2008-09-08 23:14:50 -04001055repeat:
Theodore Ts'o0637c6f2009-12-30 14:20:45 -05001056 spin_lock(&ei->i_block_reservation_lock);
Theodore Ts'o9d0be502010-01-01 02:41:30 -05001057 md_needed = ext4_calc_metadata_amount(inode, lblock);
Theodore Ts'of8ec9d682010-01-01 01:00:21 -05001058 trace_ext4_da_reserve_space(inode, md_needed);
Theodore Ts'o0637c6f2009-12-30 14:20:45 -05001059 spin_unlock(&ei->i_block_reservation_lock);
Mingming Caod2a17632008-07-14 17:52:37 -04001060
Mingming Cao60e58e02009-01-22 18:13:05 +01001061 /*
Eric Sandeen72b8ab92010-05-16 11:00:00 -04001062 * We will charge metadata quota at writeout time; this saves
1063 * us from metadata over-estimation, though we may go over by
1064 * a small amount in the end. Here we just reserve for data.
Mingming Cao60e58e02009-01-22 18:13:05 +01001065 */
Eric Sandeen72b8ab92010-05-16 11:00:00 -04001066 ret = dquot_reserve_block(inode, 1);
Christoph Hellwig5dd40562010-03-03 09:05:00 -05001067 if (ret)
1068 return ret;
Eric Sandeen72b8ab92010-05-16 11:00:00 -04001069 /*
1070 * We do still charge estimated metadata to the sb though;
1071 * we cannot afford to run out of free blocks.
1072 */
Allison Henderson55f020d2011-05-25 07:41:26 -04001073 if (ext4_claim_free_blocks(sbi, md_needed + 1, 0)) {
Eric Sandeen72b8ab92010-05-16 11:00:00 -04001074 dquot_release_reservation_block(inode, 1);
Aneesh Kumar K.V030ba6b2008-09-08 23:14:50 -04001075 if (ext4_should_retry_alloc(inode->i_sb, &retries)) {
1076 yield();
1077 goto repeat;
1078 }
Mingming Caod2a17632008-07-14 17:52:37 -04001079 return -ENOSPC;
1080 }
Theodore Ts'o0637c6f2009-12-30 14:20:45 -05001081 spin_lock(&ei->i_block_reservation_lock);
Theodore Ts'o9d0be502010-01-01 02:41:30 -05001082 ei->i_reserved_data_blocks++;
Theodore Ts'o0637c6f2009-12-30 14:20:45 -05001083 ei->i_reserved_meta_blocks += md_needed;
1084 spin_unlock(&ei->i_block_reservation_lock);
Dmitry Monakhov39bc6802009-12-10 16:36:27 +00001085
Mingming Caod2a17632008-07-14 17:52:37 -04001086 return 0; /* success */
1087}
1088
Aneesh Kumar K.V12219ae2008-07-17 16:12:08 -04001089static void ext4_da_release_space(struct inode *inode, int to_free)
Mingming Caod2a17632008-07-14 17:52:37 -04001090{
1091 struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
Theodore Ts'o0637c6f2009-12-30 14:20:45 -05001092 struct ext4_inode_info *ei = EXT4_I(inode);
Mingming Caod2a17632008-07-14 17:52:37 -04001093
Mingming Caocd213222008-08-19 22:16:59 -04001094 if (!to_free)
1095 return; /* Nothing to release, exit */
1096
Mingming Caod2a17632008-07-14 17:52:37 -04001097 spin_lock(&EXT4_I(inode)->i_block_reservation_lock);
Mingming Caocd213222008-08-19 22:16:59 -04001098
Li Zefan5a58ec82010-05-17 02:00:00 -04001099 trace_ext4_da_release_space(inode, to_free);
Theodore Ts'o0637c6f2009-12-30 14:20:45 -05001100 if (unlikely(to_free > ei->i_reserved_data_blocks)) {
Mingming Caocd213222008-08-19 22:16:59 -04001101 /*
Theodore Ts'o0637c6f2009-12-30 14:20:45 -05001102 * if there aren't enough reserved blocks, then the
1103 * counter is messed up somewhere. Since this
1104 * function is called from invalidate page, it's
1105 * harmless to return without any action.
Mingming Caocd213222008-08-19 22:16:59 -04001106 */
Theodore Ts'o0637c6f2009-12-30 14:20:45 -05001107 ext4_msg(inode->i_sb, KERN_NOTICE, "ext4_da_release_space: "
1108 "ino %lu, to_free %d with only %d reserved "
1109 "data blocks\n", inode->i_ino, to_free,
1110 ei->i_reserved_data_blocks);
1111 WARN_ON(1);
1112 to_free = ei->i_reserved_data_blocks;
1113 }
1114 ei->i_reserved_data_blocks -= to_free;
1115
1116 if (ei->i_reserved_data_blocks == 0) {
1117 /*
1118 * We can release all of the reserved metadata blocks
1119 * only when we have written all of the delayed
1120 * allocation blocks.
1121 */
Eric Sandeen72b8ab92010-05-16 11:00:00 -04001122 percpu_counter_sub(&sbi->s_dirtyblocks_counter,
1123 ei->i_reserved_meta_blocks);
Theodore Ts'oee5f4d92010-01-01 02:36:15 -05001124 ei->i_reserved_meta_blocks = 0;
Theodore Ts'o9d0be502010-01-01 02:41:30 -05001125 ei->i_da_metadata_calc_len = 0;
Mingming Caocd213222008-08-19 22:16:59 -04001126 }
1127
Eric Sandeen72b8ab92010-05-16 11:00:00 -04001128 /* update fs dirty data blocks counter */
Theodore Ts'o0637c6f2009-12-30 14:20:45 -05001129 percpu_counter_sub(&sbi->s_dirtyblocks_counter, to_free);
Mingming Caod2a17632008-07-14 17:52:37 -04001130
Mingming Caod2a17632008-07-14 17:52:37 -04001131 spin_unlock(&EXT4_I(inode)->i_block_reservation_lock);
Mingming Cao60e58e02009-01-22 18:13:05 +01001132
Christoph Hellwig5dd40562010-03-03 09:05:00 -05001133 dquot_release_reservation_block(inode, to_free);
Mingming Caod2a17632008-07-14 17:52:37 -04001134}
1135
1136static void ext4_da_page_release_reservation(struct page *page,
Theodore Ts'ode9a55b2009-06-14 17:45:34 -04001137 unsigned long offset)
Mingming Caod2a17632008-07-14 17:52:37 -04001138{
1139 int to_release = 0;
1140 struct buffer_head *head, *bh;
1141 unsigned int curr_off = 0;
1142
1143 head = page_buffers(page);
1144 bh = head;
1145 do {
1146 unsigned int next_off = curr_off + bh->b_size;
1147
1148 if ((offset <= curr_off) && (buffer_delay(bh))) {
1149 to_release++;
1150 clear_buffer_delay(bh);
1151 }
1152 curr_off = next_off;
1153 } while ((bh = bh->b_this_page) != head);
Aneesh Kumar K.V12219ae2008-07-17 16:12:08 -04001154 ext4_da_release_space(page->mapping->host, to_release);
Mingming Caod2a17632008-07-14 17:52:37 -04001155}
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001156
1157/*
Alex Tomas64769242008-07-11 19:27:31 -04001158 * Delayed allocation stuff
1159 */
1160
Alex Tomas64769242008-07-11 19:27:31 -04001161/*
1162 * mpage_da_submit_io - walks through extent of pages and try to write
Aneesh Kumar K.Va1d6cc52008-08-19 21:55:02 -04001163 * them with writepage() call back
Alex Tomas64769242008-07-11 19:27:31 -04001164 *
1165 * @mpd->inode: inode
1166 * @mpd->first_page: first page of the extent
1167 * @mpd->next_page: page after the last page of the extent
Alex Tomas64769242008-07-11 19:27:31 -04001168 *
1169 * By the time mpage_da_submit_io() is called we expect all blocks
1170 * to be allocated. this may be wrong if allocation failed.
1171 *
1172 * As pages are already locked by write_cache_pages(), we can't use it
1173 */
Theodore Ts'o1de3e3d2010-10-27 21:30:10 -04001174static int mpage_da_submit_io(struct mpage_da_data *mpd,
1175 struct ext4_map_blocks *map)
Alex Tomas64769242008-07-11 19:27:31 -04001176{
Aneesh Kumar K.V791b7f02009-01-05 21:50:43 -05001177 struct pagevec pvec;
1178 unsigned long index, end;
1179 int ret = 0, err, nr_pages, i;
1180 struct inode *inode = mpd->inode;
1181 struct address_space *mapping = inode->i_mapping;
Theodore Ts'ocb20d512010-10-27 21:30:09 -04001182 loff_t size = i_size_read(inode);
Theodore Ts'o3ecdb3a2010-10-27 21:30:10 -04001183 unsigned int len, block_start;
1184 struct buffer_head *bh, *page_bufs = NULL;
Theodore Ts'ocb20d512010-10-27 21:30:09 -04001185 int journal_data = ext4_should_journal_data(inode);
Theodore Ts'o1de3e3d2010-10-27 21:30:10 -04001186 sector_t pblock = 0, cur_logical = 0;
Theodore Ts'obd2d0212010-10-27 21:30:10 -04001187 struct ext4_io_submit io_submit;
Alex Tomas64769242008-07-11 19:27:31 -04001188
1189 BUG_ON(mpd->next_page <= mpd->first_page);
Theodore Ts'obd2d0212010-10-27 21:30:10 -04001190 memset(&io_submit, 0, sizeof(io_submit));
Aneesh Kumar K.V791b7f02009-01-05 21:50:43 -05001191 /*
1192 * We need to start from the first_page to the next_page - 1
1193 * to make sure we also write the mapped dirty buffer_heads.
Theodore Ts'o8dc207c2009-02-23 06:46:01 -05001194 * If we look at mpd->b_blocknr we would only be looking
Aneesh Kumar K.V791b7f02009-01-05 21:50:43 -05001195 * at the currently mapped buffer_heads.
1196 */
Alex Tomas64769242008-07-11 19:27:31 -04001197 index = mpd->first_page;
1198 end = mpd->next_page - 1;
1199
Aneesh Kumar K.V791b7f02009-01-05 21:50:43 -05001200 pagevec_init(&pvec, 0);
Alex Tomas64769242008-07-11 19:27:31 -04001201 while (index <= end) {
Aneesh Kumar K.V791b7f02009-01-05 21:50:43 -05001202 nr_pages = pagevec_lookup(&pvec, mapping, index, PAGEVEC_SIZE);
Alex Tomas64769242008-07-11 19:27:31 -04001203 if (nr_pages == 0)
1204 break;
1205 for (i = 0; i < nr_pages; i++) {
Theodore Ts'o97498952011-02-26 14:08:01 -05001206 int commit_write = 0, skip_page = 0;
Alex Tomas64769242008-07-11 19:27:31 -04001207 struct page *page = pvec.pages[i];
1208
Aneesh Kumar K.V791b7f02009-01-05 21:50:43 -05001209 index = page->index;
1210 if (index > end)
1211 break;
Theodore Ts'ocb20d512010-10-27 21:30:09 -04001212
1213 if (index == size >> PAGE_CACHE_SHIFT)
1214 len = size & ~PAGE_CACHE_MASK;
1215 else
1216 len = PAGE_CACHE_SIZE;
Theodore Ts'o1de3e3d2010-10-27 21:30:10 -04001217 if (map) {
1218 cur_logical = index << (PAGE_CACHE_SHIFT -
1219 inode->i_blkbits);
1220 pblock = map->m_pblk + (cur_logical -
1221 map->m_lblk);
1222 }
Aneesh Kumar K.V791b7f02009-01-05 21:50:43 -05001223 index++;
1224
1225 BUG_ON(!PageLocked(page));
1226 BUG_ON(PageWriteback(page));
1227
Theodore Ts'ocb20d512010-10-27 21:30:09 -04001228 /*
1229 * If the page does not have buffers (for
1230 * whatever reason), try to create them using
Theodore Ts'oa107e5a2010-10-27 23:44:47 -04001231 * __block_write_begin. If this fails,
Theodore Ts'o97498952011-02-26 14:08:01 -05001232 * skip the page and move on.
Theodore Ts'ocb20d512010-10-27 21:30:09 -04001233 */
1234 if (!page_has_buffers(page)) {
Theodore Ts'oa107e5a2010-10-27 23:44:47 -04001235 if (__block_write_begin(page, 0, len,
Theodore Ts'ocb20d512010-10-27 21:30:09 -04001236 noalloc_get_block_write)) {
Theodore Ts'o97498952011-02-26 14:08:01 -05001237 skip_page:
Theodore Ts'ocb20d512010-10-27 21:30:09 -04001238 unlock_page(page);
1239 continue;
1240 }
1241 commit_write = 1;
1242 }
Theodore Ts'o3ecdb3a2010-10-27 21:30:10 -04001243
1244 bh = page_bufs = page_buffers(page);
1245 block_start = 0;
1246 do {
Theodore Ts'o1de3e3d2010-10-27 21:30:10 -04001247 if (!bh)
Theodore Ts'o97498952011-02-26 14:08:01 -05001248 goto skip_page;
Theodore Ts'o1de3e3d2010-10-27 21:30:10 -04001249 if (map && (cur_logical >= map->m_lblk) &&
1250 (cur_logical <= (map->m_lblk +
1251 (map->m_len - 1)))) {
1252 if (buffer_delay(bh)) {
1253 clear_buffer_delay(bh);
1254 bh->b_blocknr = pblock;
1255 }
1256 if (buffer_unwritten(bh) ||
1257 buffer_mapped(bh))
1258 BUG_ON(bh->b_blocknr != pblock);
1259 if (map->m_flags & EXT4_MAP_UNINIT)
1260 set_buffer_uninit(bh);
1261 clear_buffer_unwritten(bh);
1262 }
1263
Theodore Ts'o97498952011-02-26 14:08:01 -05001264 /* skip page if block allocation undone */
Theodore Ts'o1de3e3d2010-10-27 21:30:10 -04001265 if (buffer_delay(bh) || buffer_unwritten(bh))
Theodore Ts'o97498952011-02-26 14:08:01 -05001266 skip_page = 1;
Theodore Ts'o3ecdb3a2010-10-27 21:30:10 -04001267 bh = bh->b_this_page;
1268 block_start += bh->b_size;
Theodore Ts'o1de3e3d2010-10-27 21:30:10 -04001269 cur_logical++;
1270 pblock++;
1271 } while (bh != page_bufs);
1272
Theodore Ts'o97498952011-02-26 14:08:01 -05001273 if (skip_page)
1274 goto skip_page;
Theodore Ts'ocb20d512010-10-27 21:30:09 -04001275
1276 if (commit_write)
1277 /* mark the buffer_heads as dirty & uptodate */
1278 block_commit_write(page, 0, len);
1279
Theodore Ts'o97498952011-02-26 14:08:01 -05001280 clear_page_dirty_for_io(page);
Theodore Ts'obd2d0212010-10-27 21:30:10 -04001281 /*
1282 * Delalloc doesn't support data journalling,
1283 * but eventually maybe we'll lift this
1284 * restriction.
1285 */
1286 if (unlikely(journal_data && PageChecked(page)))
Theodore Ts'ocb20d512010-10-27 21:30:09 -04001287 err = __ext4_journalled_writepage(page, len);
Theodore Ts'o14490322010-12-14 15:27:50 -05001288 else if (test_opt(inode->i_sb, MBLK_IO_SUBMIT))
Theodore Ts'obd2d0212010-10-27 21:30:10 -04001289 err = ext4_bio_write_page(&io_submit, page,
1290 len, mpd->wbc);
Theodore Ts'o9dd75f12011-08-13 12:58:21 -04001291 else if (buffer_uninit(page_bufs)) {
1292 ext4_set_bh_endio(page_bufs, inode);
1293 err = block_write_full_page_endio(page,
1294 noalloc_get_block_write,
1295 mpd->wbc, ext4_end_io_buffer_write);
1296 } else
Theodore Ts'o14490322010-12-14 15:27:50 -05001297 err = block_write_full_page(page,
1298 noalloc_get_block_write, mpd->wbc);
Theodore Ts'ocb20d512010-10-27 21:30:09 -04001299
1300 if (!err)
Aneesh Kumar K.Va1d6cc52008-08-19 21:55:02 -04001301 mpd->pages_written++;
Alex Tomas64769242008-07-11 19:27:31 -04001302 /*
1303 * In error case, we have to continue because
1304 * remaining pages are still locked
Alex Tomas64769242008-07-11 19:27:31 -04001305 */
1306 if (ret == 0)
1307 ret = err;
1308 }
1309 pagevec_release(&pvec);
1310 }
Theodore Ts'obd2d0212010-10-27 21:30:10 -04001311 ext4_io_submit(&io_submit);
Alex Tomas64769242008-07-11 19:27:31 -04001312 return ret;
1313}
1314
Curt Wohlgemuthc7f59382011-02-26 12:27:52 -05001315static void ext4_da_block_invalidatepages(struct mpage_da_data *mpd)
Aneesh Kumar K.Vc4a0c462008-08-19 21:08:18 -04001316{
1317 int nr_pages, i;
1318 pgoff_t index, end;
1319 struct pagevec pvec;
1320 struct inode *inode = mpd->inode;
1321 struct address_space *mapping = inode->i_mapping;
1322
Curt Wohlgemuthc7f59382011-02-26 12:27:52 -05001323 index = mpd->first_page;
1324 end = mpd->next_page - 1;
Aneesh Kumar K.Vc4a0c462008-08-19 21:08:18 -04001325 while (index <= end) {
1326 nr_pages = pagevec_lookup(&pvec, mapping, index, PAGEVEC_SIZE);
1327 if (nr_pages == 0)
1328 break;
1329 for (i = 0; i < nr_pages; i++) {
1330 struct page *page = pvec.pages[i];
Jan Kara9b1d09982010-03-03 16:19:32 -05001331 if (page->index > end)
Aneesh Kumar K.Vc4a0c462008-08-19 21:08:18 -04001332 break;
Aneesh Kumar K.Vc4a0c462008-08-19 21:08:18 -04001333 BUG_ON(!PageLocked(page));
1334 BUG_ON(PageWriteback(page));
1335 block_invalidatepage(page, 0);
1336 ClearPageUptodate(page);
1337 unlock_page(page);
1338 }
Jan Kara9b1d09982010-03-03 16:19:32 -05001339 index = pvec.pages[nr_pages - 1]->index + 1;
1340 pagevec_release(&pvec);
Aneesh Kumar K.Vc4a0c462008-08-19 21:08:18 -04001341 }
1342 return;
1343}
1344
Aneesh Kumar K.Vdf222912008-09-08 23:05:34 -04001345static void ext4_print_free_blocks(struct inode *inode)
1346{
1347 struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
Theodore Ts'o16939182009-09-26 17:43:59 -04001348 printk(KERN_CRIT "Total free blocks count %lld\n",
1349 ext4_count_free_blocks(inode->i_sb));
1350 printk(KERN_CRIT "Free/Dirty block details\n");
1351 printk(KERN_CRIT "free_blocks=%lld\n",
1352 (long long) percpu_counter_sum(&sbi->s_freeblocks_counter));
1353 printk(KERN_CRIT "dirty_blocks=%lld\n",
1354 (long long) percpu_counter_sum(&sbi->s_dirtyblocks_counter));
1355 printk(KERN_CRIT "Block reservation details\n");
1356 printk(KERN_CRIT "i_reserved_data_blocks=%u\n",
1357 EXT4_I(inode)->i_reserved_data_blocks);
1358 printk(KERN_CRIT "i_reserved_meta_blocks=%u\n",
1359 EXT4_I(inode)->i_reserved_meta_blocks);
Aneesh Kumar K.Vdf222912008-09-08 23:05:34 -04001360 return;
1361}
1362
Theodore Ts'ob920c752009-05-14 00:54:29 -04001363/*
Theodore Ts'o5a87b7a2010-10-27 21:30:09 -04001364 * mpage_da_map_and_submit - go through given space, map them
1365 * if necessary, and then submit them for I/O
Alex Tomas64769242008-07-11 19:27:31 -04001366 *
Theodore Ts'o8dc207c2009-02-23 06:46:01 -05001367 * @mpd - bh describing space
Alex Tomas64769242008-07-11 19:27:31 -04001368 *
1369 * The function skips space we know is already mapped to disk blocks.
1370 *
Alex Tomas64769242008-07-11 19:27:31 -04001371 */
Theodore Ts'o5a87b7a2010-10-27 21:30:09 -04001372static void mpage_da_map_and_submit(struct mpage_da_data *mpd)
Alex Tomas64769242008-07-11 19:27:31 -04001373{
Theodore Ts'o2ac3b6e2009-05-14 13:57:08 -04001374 int err, blks, get_blocks_flags;
Theodore Ts'o1de3e3d2010-10-27 21:30:10 -04001375 struct ext4_map_blocks map, *mapp = NULL;
Theodore Ts'o2fa3cdf2009-05-14 09:29:45 -04001376 sector_t next = mpd->b_blocknr;
1377 unsigned max_blocks = mpd->b_size >> mpd->inode->i_blkbits;
1378 loff_t disksize = EXT4_I(mpd->inode)->i_disksize;
1379 handle_t *handle = NULL;
Alex Tomas64769242008-07-11 19:27:31 -04001380
1381 /*
Theodore Ts'o5a87b7a2010-10-27 21:30:09 -04001382 * If the blocks are mapped already, or we couldn't accumulate
1383 * any blocks, then proceed immediately to the submission stage.
Alex Tomas64769242008-07-11 19:27:31 -04001384 */
Theodore Ts'o5a87b7a2010-10-27 21:30:09 -04001385 if ((mpd->b_size == 0) ||
1386 ((mpd->b_state & (1 << BH_Mapped)) &&
1387 !(mpd->b_state & (1 << BH_Delay)) &&
1388 !(mpd->b_state & (1 << BH_Unwritten))))
1389 goto submit_io;
Theodore Ts'o2fa3cdf2009-05-14 09:29:45 -04001390
1391 handle = ext4_journal_current_handle();
1392 BUG_ON(!handle);
1393
Aneesh Kumar K.V79ffab32009-05-13 15:13:42 -04001394 /*
Eric Sandeen79e83032010-07-27 11:56:07 -04001395 * Call ext4_map_blocks() to allocate any delayed allocation
Theodore Ts'o2ac3b6e2009-05-14 13:57:08 -04001396 * blocks, or to convert an uninitialized extent to be
1397 * initialized (in the case where we have written into
1398 * one or more preallocated blocks).
1399 *
1400 * We pass in the magic EXT4_GET_BLOCKS_DELALLOC_RESERVE to
1401 * indicate that we are on the delayed allocation path. This
1402 * affects functions in many different parts of the allocation
1403 * call path. This flag exists primarily because we don't
Eric Sandeen79e83032010-07-27 11:56:07 -04001404 * want to change *many* call functions, so ext4_map_blocks()
Theodore Ts'of2321092011-01-10 12:12:36 -05001405 * will set the EXT4_STATE_DELALLOC_RESERVED flag once the
Theodore Ts'o2ac3b6e2009-05-14 13:57:08 -04001406 * inode's allocation semaphore is taken.
1407 *
1408 * If the blocks in questions were delalloc blocks, set
1409 * EXT4_GET_BLOCKS_DELALLOC_RESERVE so the delalloc accounting
1410 * variables are updated after the blocks have been allocated.
Aneesh Kumar K.V79ffab32009-05-13 15:13:42 -04001411 */
Theodore Ts'o2ed88682010-05-16 20:00:00 -04001412 map.m_lblk = next;
1413 map.m_len = max_blocks;
Aneesh Kumar K.V1296cc82010-01-15 01:27:59 -05001414 get_blocks_flags = EXT4_GET_BLOCKS_CREATE;
Jiaying Zhang744692d2010-03-04 16:14:02 -05001415 if (ext4_should_dioread_nolock(mpd->inode))
1416 get_blocks_flags |= EXT4_GET_BLOCKS_IO_CREATE_EXT;
Theodore Ts'o2ac3b6e2009-05-14 13:57:08 -04001417 if (mpd->b_state & (1 << BH_Delay))
Aneesh Kumar K.V1296cc82010-01-15 01:27:59 -05001418 get_blocks_flags |= EXT4_GET_BLOCKS_DELALLOC_RESERVE;
1419
Theodore Ts'o2ed88682010-05-16 20:00:00 -04001420 blks = ext4_map_blocks(handle, mpd->inode, &map, get_blocks_flags);
Theodore Ts'o2fa3cdf2009-05-14 09:29:45 -04001421 if (blks < 0) {
Eric Sandeene3570632010-07-27 11:56:08 -04001422 struct super_block *sb = mpd->inode->i_sb;
1423
Theodore Ts'o2fa3cdf2009-05-14 09:29:45 -04001424 err = blks;
Theodore Ts'oed5bde02009-02-23 10:48:07 -05001425 /*
Theodore Ts'o5a87b7a2010-10-27 21:30:09 -04001426 * If get block returns EAGAIN or ENOSPC and there
Theodore Ts'o97498952011-02-26 14:08:01 -05001427 * appears to be free blocks we will just let
1428 * mpage_da_submit_io() unlock all of the pages.
Aneesh Kumar K.Vc4a0c462008-08-19 21:08:18 -04001429 */
1430 if (err == -EAGAIN)
Theodore Ts'o5a87b7a2010-10-27 21:30:09 -04001431 goto submit_io;
Aneesh Kumar K.Vdf222912008-09-08 23:05:34 -04001432
1433 if (err == -ENOSPC &&
Eric Sandeene3570632010-07-27 11:56:08 -04001434 ext4_count_free_blocks(sb)) {
Aneesh Kumar K.Vdf222912008-09-08 23:05:34 -04001435 mpd->retval = err;
Theodore Ts'o5a87b7a2010-10-27 21:30:09 -04001436 goto submit_io;
Aneesh Kumar K.Vdf222912008-09-08 23:05:34 -04001437 }
1438
Aneesh Kumar K.Vc4a0c462008-08-19 21:08:18 -04001439 /*
Theodore Ts'oed5bde02009-02-23 10:48:07 -05001440 * get block failure will cause us to loop in
1441 * writepages, because a_ops->writepage won't be able
1442 * to make progress. The page will be redirtied by
1443 * writepage and writepages will again try to write
1444 * the same.
Aneesh Kumar K.Vc4a0c462008-08-19 21:08:18 -04001445 */
Eric Sandeene3570632010-07-27 11:56:08 -04001446 if (!(EXT4_SB(sb)->s_mount_flags & EXT4_MF_FS_ABORTED)) {
1447 ext4_msg(sb, KERN_CRIT,
1448 "delayed block allocation failed for inode %lu "
1449 "at logical offset %llu with max blocks %zd "
1450 "with error %d", mpd->inode->i_ino,
1451 (unsigned long long) next,
1452 mpd->b_size >> mpd->inode->i_blkbits, err);
1453 ext4_msg(sb, KERN_CRIT,
1454 "This should not happen!! Data will be lost\n");
1455 if (err == -ENOSPC)
1456 ext4_print_free_blocks(mpd->inode);
Aneesh Kumar K.V030ba6b2008-09-08 23:14:50 -04001457 }
Theodore Ts'o2fa3cdf2009-05-14 09:29:45 -04001458 /* invalidate all the pages */
Curt Wohlgemuthc7f59382011-02-26 12:27:52 -05001459 ext4_da_block_invalidatepages(mpd);
Curt Wohlgemuthe0fd9b92011-02-26 12:25:52 -05001460
1461 /* Mark this page range as having been completed */
1462 mpd->io_done = 1;
Theodore Ts'o5a87b7a2010-10-27 21:30:09 -04001463 return;
Aneesh Kumar K.Vc4a0c462008-08-19 21:08:18 -04001464 }
Theodore Ts'o2fa3cdf2009-05-14 09:29:45 -04001465 BUG_ON(blks == 0);
1466
Theodore Ts'o1de3e3d2010-10-27 21:30:10 -04001467 mapp = &map;
Theodore Ts'o2ed88682010-05-16 20:00:00 -04001468 if (map.m_flags & EXT4_MAP_NEW) {
1469 struct block_device *bdev = mpd->inode->i_sb->s_bdev;
1470 int i;
Alex Tomas64769242008-07-11 19:27:31 -04001471
Theodore Ts'o2ed88682010-05-16 20:00:00 -04001472 for (i = 0; i < map.m_len; i++)
1473 unmap_underlying_metadata(bdev, map.m_pblk + i);
1474 }
Alex Tomas64769242008-07-11 19:27:31 -04001475
Theodore Ts'o2fa3cdf2009-05-14 09:29:45 -04001476 if (ext4_should_order_data(mpd->inode)) {
1477 err = ext4_jbd2_file_inode(handle, mpd->inode);
1478 if (err)
Theodore Ts'o5a87b7a2010-10-27 21:30:09 -04001479 /* This only happens if the journal is aborted */
1480 return;
Theodore Ts'o2fa3cdf2009-05-14 09:29:45 -04001481 }
1482
1483 /*
Jan Kara03f5d8b2009-06-09 00:17:05 -04001484 * Update on-disk size along with block allocation.
Theodore Ts'o2fa3cdf2009-05-14 09:29:45 -04001485 */
1486 disksize = ((loff_t) next + blks) << mpd->inode->i_blkbits;
1487 if (disksize > i_size_read(mpd->inode))
1488 disksize = i_size_read(mpd->inode);
1489 if (disksize > EXT4_I(mpd->inode)->i_disksize) {
1490 ext4_update_i_disksize(mpd->inode, disksize);
Theodore Ts'o5a87b7a2010-10-27 21:30:09 -04001491 err = ext4_mark_inode_dirty(handle, mpd->inode);
1492 if (err)
1493 ext4_error(mpd->inode->i_sb,
1494 "Failed to mark inode %lu dirty",
1495 mpd->inode->i_ino);
Theodore Ts'o2fa3cdf2009-05-14 09:29:45 -04001496 }
1497
Theodore Ts'o5a87b7a2010-10-27 21:30:09 -04001498submit_io:
Theodore Ts'o1de3e3d2010-10-27 21:30:10 -04001499 mpage_da_submit_io(mpd, mapp);
Theodore Ts'o5a87b7a2010-10-27 21:30:09 -04001500 mpd->io_done = 1;
Alex Tomas64769242008-07-11 19:27:31 -04001501}
1502
Aneesh Kumar K.Vbf068ee2008-08-19 22:16:43 -04001503#define BH_FLAGS ((1 << BH_Uptodate) | (1 << BH_Mapped) | \
1504 (1 << BH_Delay) | (1 << BH_Unwritten))
Alex Tomas64769242008-07-11 19:27:31 -04001505
1506/*
1507 * mpage_add_bh_to_extent - try to add one more block to extent of blocks
1508 *
1509 * @mpd->lbh - extent of blocks
1510 * @logical - logical number of the block in the file
1511 * @bh - bh of the block (used to access block's state)
1512 *
1513 * the function is used to collect contig. blocks in same state
1514 */
1515static void mpage_add_bh_to_extent(struct mpage_da_data *mpd,
Theodore Ts'o8dc207c2009-02-23 06:46:01 -05001516 sector_t logical, size_t b_size,
1517 unsigned long b_state)
Alex Tomas64769242008-07-11 19:27:31 -04001518{
Alex Tomas64769242008-07-11 19:27:31 -04001519 sector_t next;
Theodore Ts'o8dc207c2009-02-23 06:46:01 -05001520 int nrblocks = mpd->b_size >> mpd->inode->i_blkbits;
Alex Tomas64769242008-07-11 19:27:31 -04001521
Eric Sandeenc445e3e2010-05-16 04:00:00 -04001522 /*
1523 * XXX Don't go larger than mballoc is willing to allocate
1524 * This is a stopgap solution. We eventually need to fold
1525 * mpage_da_submit_io() into this function and then call
Eric Sandeen79e83032010-07-27 11:56:07 -04001526 * ext4_map_blocks() multiple times in a loop
Eric Sandeenc445e3e2010-05-16 04:00:00 -04001527 */
1528 if (nrblocks >= 8*1024*1024/mpd->inode->i_sb->s_blocksize)
1529 goto flush_it;
1530
Mingming Cao525f4ed2008-08-19 22:15:58 -04001531 /* check if thereserved journal credits might overflow */
Dmitry Monakhov12e9b892010-05-16 22:00:00 -04001532 if (!(ext4_test_inode_flag(mpd->inode, EXT4_INODE_EXTENTS))) {
Mingming Cao525f4ed2008-08-19 22:15:58 -04001533 if (nrblocks >= EXT4_MAX_TRANS_DATA) {
1534 /*
1535 * With non-extent format we are limited by the journal
1536 * credit available. Total credit needed to insert
1537 * nrblocks contiguous blocks is dependent on the
1538 * nrblocks. So limit nrblocks.
1539 */
1540 goto flush_it;
1541 } else if ((nrblocks + (b_size >> mpd->inode->i_blkbits)) >
1542 EXT4_MAX_TRANS_DATA) {
1543 /*
1544 * Adding the new buffer_head would make it cross the
1545 * allowed limit for which we have journal credit
1546 * reserved. So limit the new bh->b_size
1547 */
1548 b_size = (EXT4_MAX_TRANS_DATA - nrblocks) <<
1549 mpd->inode->i_blkbits;
1550 /* we will do mpage_da_submit_io in the next loop */
1551 }
1552 }
Alex Tomas64769242008-07-11 19:27:31 -04001553 /*
1554 * First block in the extent
1555 */
Theodore Ts'o8dc207c2009-02-23 06:46:01 -05001556 if (mpd->b_size == 0) {
1557 mpd->b_blocknr = logical;
1558 mpd->b_size = b_size;
1559 mpd->b_state = b_state & BH_FLAGS;
Alex Tomas64769242008-07-11 19:27:31 -04001560 return;
1561 }
1562
Theodore Ts'o8dc207c2009-02-23 06:46:01 -05001563 next = mpd->b_blocknr + nrblocks;
Alex Tomas64769242008-07-11 19:27:31 -04001564 /*
1565 * Can we merge the block to our big extent?
1566 */
Theodore Ts'o8dc207c2009-02-23 06:46:01 -05001567 if (logical == next && (b_state & BH_FLAGS) == mpd->b_state) {
1568 mpd->b_size += b_size;
Alex Tomas64769242008-07-11 19:27:31 -04001569 return;
1570 }
1571
Mingming Cao525f4ed2008-08-19 22:15:58 -04001572flush_it:
Alex Tomas64769242008-07-11 19:27:31 -04001573 /*
1574 * We couldn't merge the block to our extent, so we
1575 * need to flush current extent and start new one
1576 */
Theodore Ts'o5a87b7a2010-10-27 21:30:09 -04001577 mpage_da_map_and_submit(mpd);
Aneesh Kumar K.Va1d6cc52008-08-19 21:55:02 -04001578 return;
Alex Tomas64769242008-07-11 19:27:31 -04001579}
1580
Aneesh Kumar K.Vc364b222009-06-14 17:57:10 -04001581static int ext4_bh_delay_or_unwritten(handle_t *handle, struct buffer_head *bh)
Aneesh Kumar K.V29fa89d2009-05-12 16:30:27 -04001582{
Aneesh Kumar K.Vc364b222009-06-14 17:57:10 -04001583 return (buffer_delay(bh) || buffer_unwritten(bh)) && buffer_dirty(bh);
Aneesh Kumar K.V29fa89d2009-05-12 16:30:27 -04001584}
1585
Alex Tomas64769242008-07-11 19:27:31 -04001586/*
Theodore Ts'ob920c752009-05-14 00:54:29 -04001587 * This is a special get_blocks_t callback which is used by
1588 * ext4_da_write_begin(). It will either return mapped block or
1589 * reserve space for a single block.
Aneesh Kumar K.V29fa89d2009-05-12 16:30:27 -04001590 *
1591 * For delayed buffer_head we have BH_Mapped, BH_New, BH_Delay set.
1592 * We also have b_blocknr = -1 and b_bdev initialized properly
1593 *
1594 * For unwritten buffer_head we have BH_Mapped, BH_New, BH_Unwritten set.
1595 * We also have b_blocknr = physicalblock mapping unwritten extent and b_bdev
1596 * initialized properly.
Alex Tomas64769242008-07-11 19:27:31 -04001597 */
1598static int ext4_da_get_block_prep(struct inode *inode, sector_t iblock,
Theodore Ts'o2ed88682010-05-16 20:00:00 -04001599 struct buffer_head *bh, int create)
Alex Tomas64769242008-07-11 19:27:31 -04001600{
Theodore Ts'o2ed88682010-05-16 20:00:00 -04001601 struct ext4_map_blocks map;
Alex Tomas64769242008-07-11 19:27:31 -04001602 int ret = 0;
Aneesh Kumar K.V33b98172009-05-12 14:40:37 -04001603 sector_t invalid_block = ~((sector_t) 0xffff);
1604
1605 if (invalid_block < ext4_blocks_count(EXT4_SB(inode->i_sb)->s_es))
1606 invalid_block = ~0;
Alex Tomas64769242008-07-11 19:27:31 -04001607
1608 BUG_ON(create == 0);
Theodore Ts'o2ed88682010-05-16 20:00:00 -04001609 BUG_ON(bh->b_size != inode->i_sb->s_blocksize);
1610
1611 map.m_lblk = iblock;
1612 map.m_len = 1;
Alex Tomas64769242008-07-11 19:27:31 -04001613
1614 /*
1615 * first, we need to know whether the block is allocated already
1616 * preallocated blocks are unmapped but should treated
1617 * the same as allocated blocks.
1618 */
Theodore Ts'o2ed88682010-05-16 20:00:00 -04001619 ret = ext4_map_blocks(NULL, inode, &map, 0);
1620 if (ret < 0)
1621 return ret;
1622 if (ret == 0) {
1623 if (buffer_delay(bh))
1624 return 0; /* Not sure this could or should happen */
Alex Tomas64769242008-07-11 19:27:31 -04001625 /*
Christoph Hellwigebdec242010-10-06 10:47:23 +02001626 * XXX: __block_write_begin() unmaps passed block, is it OK?
Alex Tomas64769242008-07-11 19:27:31 -04001627 */
Theodore Ts'o9d0be502010-01-01 02:41:30 -05001628 ret = ext4_da_reserve_space(inode, iblock);
Mingming Caod2a17632008-07-14 17:52:37 -04001629 if (ret)
1630 /* not enough space to reserve */
1631 return ret;
1632
Theodore Ts'o2ed88682010-05-16 20:00:00 -04001633 map_bh(bh, inode->i_sb, invalid_block);
1634 set_buffer_new(bh);
1635 set_buffer_delay(bh);
1636 return 0;
Alex Tomas64769242008-07-11 19:27:31 -04001637 }
1638
Theodore Ts'o2ed88682010-05-16 20:00:00 -04001639 map_bh(bh, inode->i_sb, map.m_pblk);
1640 bh->b_state = (bh->b_state & ~EXT4_MAP_FLAGS) | map.m_flags;
1641
1642 if (buffer_unwritten(bh)) {
1643 /* A delayed write to unwritten bh should be marked
1644 * new and mapped. Mapped ensures that we don't do
1645 * get_block multiple times when we write to the same
1646 * offset and new ensures that we do proper zero out
1647 * for partial write.
1648 */
1649 set_buffer_new(bh);
Theodore Ts'oc8205632011-04-10 22:30:07 -04001650 set_buffer_mapped(bh);
Theodore Ts'o2ed88682010-05-16 20:00:00 -04001651 }
1652 return 0;
Alex Tomas64769242008-07-11 19:27:31 -04001653}
Mingming Cao61628a32008-07-11 19:27:31 -04001654
Theodore Ts'ob920c752009-05-14 00:54:29 -04001655/*
1656 * This function is used as a standard get_block_t calback function
1657 * when there is no desire to allocate any blocks. It is used as a
Christoph Hellwigebdec242010-10-06 10:47:23 +02001658 * callback function for block_write_begin() and block_write_full_page().
Christoph Hellwig206f7ab2010-06-14 14:42:49 -04001659 * These functions should only try to map a single block at a time.
Theodore Ts'ob920c752009-05-14 00:54:29 -04001660 *
1661 * Since this function doesn't do block allocations even if the caller
1662 * requests it by passing in create=1, it is critically important that
1663 * any caller checks to make sure that any buffer heads are returned
1664 * by this function are either all already mapped or marked for
Christoph Hellwig206f7ab2010-06-14 14:42:49 -04001665 * delayed allocation before calling block_write_full_page(). Otherwise,
1666 * b_blocknr could be left unitialized, and the page write functions will
1667 * be taken by surprise.
Theodore Ts'ob920c752009-05-14 00:54:29 -04001668 */
1669static int noalloc_get_block_write(struct inode *inode, sector_t iblock,
Aneesh Kumar K.Vf0e6c982008-07-11 19:27:31 -04001670 struct buffer_head *bh_result, int create)
1671{
Theodore Ts'oa2dc52b2009-05-12 13:51:29 -04001672 BUG_ON(bh_result->b_size != inode->i_sb->s_blocksize);
Theodore Ts'o2ed88682010-05-16 20:00:00 -04001673 return _ext4_get_block(inode, iblock, bh_result, 0);
Mingming Cao61628a32008-07-11 19:27:31 -04001674}
1675
Aneesh Kumar K.V62e086b2009-06-14 17:59:34 -04001676static int bget_one(handle_t *handle, struct buffer_head *bh)
1677{
1678 get_bh(bh);
1679 return 0;
1680}
1681
1682static int bput_one(handle_t *handle, struct buffer_head *bh)
1683{
1684 put_bh(bh);
1685 return 0;
1686}
1687
1688static int __ext4_journalled_writepage(struct page *page,
Aneesh Kumar K.V62e086b2009-06-14 17:59:34 -04001689 unsigned int len)
1690{
1691 struct address_space *mapping = page->mapping;
1692 struct inode *inode = mapping->host;
1693 struct buffer_head *page_bufs;
1694 handle_t *handle = NULL;
1695 int ret = 0;
1696 int err;
1697
Theodore Ts'ocb20d512010-10-27 21:30:09 -04001698 ClearPageChecked(page);
Aneesh Kumar K.V62e086b2009-06-14 17:59:34 -04001699 page_bufs = page_buffers(page);
1700 BUG_ON(!page_bufs);
1701 walk_page_buffers(handle, page_bufs, 0, len, NULL, bget_one);
1702 /* As soon as we unlock the page, it can go away, but we have
1703 * references to buffers so we are safe */
1704 unlock_page(page);
1705
1706 handle = ext4_journal_start(inode, ext4_writepage_trans_blocks(inode));
1707 if (IS_ERR(handle)) {
1708 ret = PTR_ERR(handle);
1709 goto out;
1710 }
1711
Curt Wohlgemuth441c8502011-08-13 11:25:18 -04001712 BUG_ON(!ext4_handle_valid(handle));
1713
Aneesh Kumar K.V62e086b2009-06-14 17:59:34 -04001714 ret = walk_page_buffers(handle, page_bufs, 0, len, NULL,
1715 do_journal_get_write_access);
1716
1717 err = walk_page_buffers(handle, page_bufs, 0, len, NULL,
1718 write_end_fn);
1719 if (ret == 0)
1720 ret = err;
Jan Kara2d859db2011-07-26 09:07:11 -04001721 EXT4_I(inode)->i_datasync_tid = handle->h_transaction->t_tid;
Aneesh Kumar K.V62e086b2009-06-14 17:59:34 -04001722 err = ext4_journal_stop(handle);
1723 if (!ret)
1724 ret = err;
1725
1726 walk_page_buffers(handle, page_bufs, 0, len, NULL, bput_one);
Theodore Ts'o19f5fb72010-01-24 14:34:07 -05001727 ext4_set_inode_state(inode, EXT4_STATE_JDATA);
Aneesh Kumar K.V62e086b2009-06-14 17:59:34 -04001728out:
1729 return ret;
1730}
1731
Jiaying Zhang744692d2010-03-04 16:14:02 -05001732static int ext4_set_bh_endio(struct buffer_head *bh, struct inode *inode);
1733static void ext4_end_io_buffer_write(struct buffer_head *bh, int uptodate);
1734
Mingming Cao61628a32008-07-11 19:27:31 -04001735/*
Aneesh Kumar K.V43ce1d22009-06-14 17:58:45 -04001736 * Note that we don't need to start a transaction unless we're journaling data
1737 * because we should have holes filled from ext4_page_mkwrite(). We even don't
1738 * need to file the inode to the transaction's list in ordered mode because if
1739 * we are writing back data added by write(), the inode is already there and if
Lucas De Marchi25985ed2011-03-30 22:57:33 -03001740 * we are writing back data modified via mmap(), no one guarantees in which
Aneesh Kumar K.V43ce1d22009-06-14 17:58:45 -04001741 * transaction the data will hit the disk. In case we are journaling data, we
1742 * cannot start transaction directly because transaction start ranks above page
1743 * lock so we have to do some magic.
1744 *
Theodore Ts'ob920c752009-05-14 00:54:29 -04001745 * This function can get called via...
1746 * - ext4_da_writepages after taking page lock (have journal handle)
1747 * - journal_submit_inode_data_buffers (no journal handle)
1748 * - shrink_page_list via pdflush (no journal handle)
1749 * - grab_page_cache when doing write_begin (have journal handle)
Aneesh Kumar K.V43ce1d22009-06-14 17:58:45 -04001750 *
1751 * We don't do any block allocation in this function. If we have page with
1752 * multiple blocks we need to write those buffer_heads that are mapped. This
1753 * is important for mmaped based write. So if we do with blocksize 1K
1754 * truncate(f, 1024);
1755 * a = mmap(f, 0, 4096);
1756 * a[0] = 'a';
1757 * truncate(f, 4096);
1758 * we have in the page first buffer_head mapped via page_mkwrite call back
1759 * but other bufer_heads would be unmapped but dirty(dirty done via the
1760 * do_wp_page). So writepage should write the first block. If we modify
1761 * the mmap area beyond 1024 we will again get a page_fault and the
1762 * page_mkwrite callback will do the block allocation and mark the
1763 * buffer_heads mapped.
1764 *
1765 * We redirty the page if we have any buffer_heads that is either delay or
1766 * unwritten in the page.
1767 *
1768 * We can get recursively called as show below.
1769 *
1770 * ext4_writepage() -> kmalloc() -> __alloc_pages() -> page_launder() ->
1771 * ext4_writepage()
1772 *
1773 * But since we don't do any block allocation we should not deadlock.
1774 * Page also have the dirty flag cleared so we don't get recurive page_lock.
Mingming Cao61628a32008-07-11 19:27:31 -04001775 */
Aneesh Kumar K.V43ce1d22009-06-14 17:58:45 -04001776static int ext4_writepage(struct page *page,
Aneesh Kumar K.V62e086b2009-06-14 17:59:34 -04001777 struct writeback_control *wbc)
Alex Tomas64769242008-07-11 19:27:31 -04001778{
Theodore Ts'oa42afc52010-10-27 21:30:09 -04001779 int ret = 0, commit_write = 0;
Mingming Cao61628a32008-07-11 19:27:31 -04001780 loff_t size;
Theodore Ts'o498e5f22008-11-05 00:14:04 -05001781 unsigned int len;
Jiaying Zhang744692d2010-03-04 16:14:02 -05001782 struct buffer_head *page_bufs = NULL;
Mingming Cao61628a32008-07-11 19:27:31 -04001783 struct inode *inode = page->mapping->host;
Alex Tomas64769242008-07-11 19:27:31 -04001784
Lukas Czernera9c667f2011-06-06 09:51:52 -04001785 trace_ext4_writepage(page);
Aneesh Kumar K.Vf0e6c982008-07-11 19:27:31 -04001786 size = i_size_read(inode);
1787 if (page->index == size >> PAGE_CACHE_SHIFT)
1788 len = size & ~PAGE_CACHE_MASK;
1789 else
1790 len = PAGE_CACHE_SIZE;
Alex Tomas64769242008-07-11 19:27:31 -04001791
Theodore Ts'oa42afc52010-10-27 21:30:09 -04001792 /*
1793 * If the page does not have buffers (for whatever reason),
Theodore Ts'oa107e5a2010-10-27 23:44:47 -04001794 * try to create them using __block_write_begin. If this
Theodore Ts'oa42afc52010-10-27 21:30:09 -04001795 * fails, redirty the page and move on.
1796 */
Theodore Ts'ob1142e82010-10-28 17:33:57 -04001797 if (!page_has_buffers(page)) {
Theodore Ts'oa107e5a2010-10-27 23:44:47 -04001798 if (__block_write_begin(page, 0, len,
Theodore Ts'oa42afc52010-10-27 21:30:09 -04001799 noalloc_get_block_write)) {
1800 redirty_page:
Aneesh Kumar K.Vf0e6c982008-07-11 19:27:31 -04001801 redirty_page_for_writepage(wbc, page);
1802 unlock_page(page);
1803 return 0;
1804 }
Theodore Ts'oa42afc52010-10-27 21:30:09 -04001805 commit_write = 1;
1806 }
1807 page_bufs = page_buffers(page);
1808 if (walk_page_buffers(NULL, page_bufs, 0, len, NULL,
1809 ext4_bh_delay_or_unwritten)) {
Aneesh Kumar K.Vf0e6c982008-07-11 19:27:31 -04001810 /*
Theodore Ts'ob1142e82010-10-28 17:33:57 -04001811 * We don't want to do block allocation, so redirty
1812 * the page and return. We may reach here when we do
1813 * a journal commit via journal_submit_inode_data_buffers.
1814 * We can also reach here via shrink_page_list
Aneesh Kumar K.Vf0e6c982008-07-11 19:27:31 -04001815 */
Theodore Ts'oa42afc52010-10-27 21:30:09 -04001816 goto redirty_page;
1817 }
1818 if (commit_write)
Aneesh Kumar K.Ved9b3e32008-11-07 09:06:45 -05001819 /* now mark the buffer_heads as dirty and uptodate */
Aneesh Kumar K.Vb767e782009-06-04 08:06:06 -04001820 block_commit_write(page, 0, len);
Alex Tomas64769242008-07-11 19:27:31 -04001821
Theodore Ts'ocb20d512010-10-27 21:30:09 -04001822 if (PageChecked(page) && ext4_should_journal_data(inode))
Aneesh Kumar K.V43ce1d22009-06-14 17:58:45 -04001823 /*
1824 * It's mmapped pagecache. Add buffers and journal it. There
1825 * doesn't seem much point in redirtying the page here.
1826 */
Wu Fengguang3f0ca302009-11-24 11:15:44 -05001827 return __ext4_journalled_writepage(page, len);
Aneesh Kumar K.V43ce1d22009-06-14 17:58:45 -04001828
Theodore Ts'oa42afc52010-10-27 21:30:09 -04001829 if (buffer_uninit(page_bufs)) {
Jiaying Zhang744692d2010-03-04 16:14:02 -05001830 ext4_set_bh_endio(page_bufs, inode);
1831 ret = block_write_full_page_endio(page, noalloc_get_block_write,
1832 wbc, ext4_end_io_buffer_write);
1833 } else
Theodore Ts'ob920c752009-05-14 00:54:29 -04001834 ret = block_write_full_page(page, noalloc_get_block_write,
1835 wbc);
Alex Tomas64769242008-07-11 19:27:31 -04001836
Alex Tomas64769242008-07-11 19:27:31 -04001837 return ret;
1838}
1839
Mingming Cao61628a32008-07-11 19:27:31 -04001840/*
Mingming Cao525f4ed2008-08-19 22:15:58 -04001841 * This is called via ext4_da_writepages() to
Lucas De Marchi25985ed2011-03-30 22:57:33 -03001842 * calculate the total number of credits to reserve to fit
Mingming Cao525f4ed2008-08-19 22:15:58 -04001843 * a single extent allocation into a single transaction,
1844 * ext4_da_writpeages() will loop calling this before
1845 * the block allocation.
Mingming Cao61628a32008-07-11 19:27:31 -04001846 */
Mingming Cao525f4ed2008-08-19 22:15:58 -04001847
1848static int ext4_da_writepages_trans_blocks(struct inode *inode)
1849{
1850 int max_blocks = EXT4_I(inode)->i_reserved_data_blocks;
1851
1852 /*
1853 * With non-extent format the journal credit needed to
1854 * insert nrblocks contiguous block is dependent on
1855 * number of contiguous block. So we will limit
1856 * number of contiguous block to a sane value
1857 */
Dmitry Monakhov12e9b892010-05-16 22:00:00 -04001858 if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)) &&
Mingming Cao525f4ed2008-08-19 22:15:58 -04001859 (max_blocks > EXT4_MAX_TRANS_DATA))
1860 max_blocks = EXT4_MAX_TRANS_DATA;
1861
1862 return ext4_chunk_trans_blocks(inode, max_blocks);
1863}
Mingming Cao61628a32008-07-11 19:27:31 -04001864
Theodore Ts'o8e48dcf2010-05-16 18:00:00 -04001865/*
1866 * write_cache_pages_da - walk the list of dirty pages of the given
Theodore Ts'o8eb9e5c2011-02-26 14:07:31 -05001867 * address space and accumulate pages that need writing, and call
Theodore Ts'o168fc022011-02-26 14:09:20 -05001868 * mpage_da_map_and_submit to map a single contiguous memory region
1869 * and then write them.
Theodore Ts'o8e48dcf2010-05-16 18:00:00 -04001870 */
1871static int write_cache_pages_da(struct address_space *mapping,
1872 struct writeback_control *wbc,
Eric Sandeen72f84e62010-10-27 21:30:13 -04001873 struct mpage_da_data *mpd,
1874 pgoff_t *done_index)
Theodore Ts'o8e48dcf2010-05-16 18:00:00 -04001875{
Theodore Ts'o4f01b022011-02-26 14:07:37 -05001876 struct buffer_head *bh, *head;
Theodore Ts'o168fc022011-02-26 14:09:20 -05001877 struct inode *inode = mapping->host;
Theodore Ts'o4f01b022011-02-26 14:07:37 -05001878 struct pagevec pvec;
1879 unsigned int nr_pages;
1880 sector_t logical;
1881 pgoff_t index, end;
1882 long nr_to_write = wbc->nr_to_write;
1883 int i, tag, ret = 0;
Theodore Ts'o8e48dcf2010-05-16 18:00:00 -04001884
Theodore Ts'o168fc022011-02-26 14:09:20 -05001885 memset(mpd, 0, sizeof(struct mpage_da_data));
1886 mpd->wbc = wbc;
1887 mpd->inode = inode;
Theodore Ts'o8e48dcf2010-05-16 18:00:00 -04001888 pagevec_init(&pvec, 0);
1889 index = wbc->range_start >> PAGE_CACHE_SHIFT;
1890 end = wbc->range_end >> PAGE_CACHE_SHIFT;
1891
Wu Fengguang6e6938b2010-06-06 10:38:15 -06001892 if (wbc->sync_mode == WB_SYNC_ALL || wbc->tagged_writepages)
Eric Sandeen5b41d922010-10-27 21:30:13 -04001893 tag = PAGECACHE_TAG_TOWRITE;
1894 else
1895 tag = PAGECACHE_TAG_DIRTY;
1896
Eric Sandeen72f84e62010-10-27 21:30:13 -04001897 *done_index = index;
Theodore Ts'o4f01b022011-02-26 14:07:37 -05001898 while (index <= end) {
Eric Sandeen5b41d922010-10-27 21:30:13 -04001899 nr_pages = pagevec_lookup_tag(&pvec, mapping, &index, tag,
Theodore Ts'o8e48dcf2010-05-16 18:00:00 -04001900 min(end - index, (pgoff_t)PAGEVEC_SIZE-1) + 1);
1901 if (nr_pages == 0)
Theodore Ts'o4f01b022011-02-26 14:07:37 -05001902 return 0;
Theodore Ts'o8e48dcf2010-05-16 18:00:00 -04001903
1904 for (i = 0; i < nr_pages; i++) {
1905 struct page *page = pvec.pages[i];
1906
1907 /*
1908 * At this point, the page may be truncated or
1909 * invalidated (changing page->mapping to NULL), or
1910 * even swizzled back from swapper_space to tmpfs file
1911 * mapping. However, page->index will not change
1912 * because we have a reference on the page.
1913 */
Theodore Ts'o4f01b022011-02-26 14:07:37 -05001914 if (page->index > end)
1915 goto out;
Theodore Ts'o8e48dcf2010-05-16 18:00:00 -04001916
Eric Sandeen72f84e62010-10-27 21:30:13 -04001917 *done_index = page->index + 1;
1918
Theodore Ts'o78aaced2011-02-26 14:09:14 -05001919 /*
1920 * If we can't merge this page, and we have
1921 * accumulated an contiguous region, write it
1922 */
1923 if ((mpd->next_page != page->index) &&
1924 (mpd->next_page != mpd->first_page)) {
1925 mpage_da_map_and_submit(mpd);
1926 goto ret_extent_tail;
1927 }
1928
Theodore Ts'o8e48dcf2010-05-16 18:00:00 -04001929 lock_page(page);
1930
1931 /*
Theodore Ts'o4f01b022011-02-26 14:07:37 -05001932 * If the page is no longer dirty, or its
1933 * mapping no longer corresponds to inode we
1934 * are writing (which means it has been
1935 * truncated or invalidated), or the page is
1936 * already under writeback and we are not
1937 * doing a data integrity writeback, skip the page
Theodore Ts'o8e48dcf2010-05-16 18:00:00 -04001938 */
Theodore Ts'o4f01b022011-02-26 14:07:37 -05001939 if (!PageDirty(page) ||
1940 (PageWriteback(page) &&
1941 (wbc->sync_mode == WB_SYNC_NONE)) ||
1942 unlikely(page->mapping != mapping)) {
Theodore Ts'o8e48dcf2010-05-16 18:00:00 -04001943 unlock_page(page);
1944 continue;
1945 }
1946
Darrick J. Wong7cb1a532011-05-18 13:53:20 -04001947 wait_on_page_writeback(page);
Theodore Ts'o8e48dcf2010-05-16 18:00:00 -04001948 BUG_ON(PageWriteback(page));
Theodore Ts'o8e48dcf2010-05-16 18:00:00 -04001949
Theodore Ts'o168fc022011-02-26 14:09:20 -05001950 if (mpd->next_page != page->index)
Theodore Ts'o8eb9e5c2011-02-26 14:07:31 -05001951 mpd->first_page = page->index;
Theodore Ts'o8eb9e5c2011-02-26 14:07:31 -05001952 mpd->next_page = page->index + 1;
1953 logical = (sector_t) page->index <<
1954 (PAGE_CACHE_SHIFT - inode->i_blkbits);
1955
1956 if (!page_has_buffers(page)) {
Theodore Ts'o4f01b022011-02-26 14:07:37 -05001957 mpage_add_bh_to_extent(mpd, logical,
1958 PAGE_CACHE_SIZE,
Theodore Ts'o8eb9e5c2011-02-26 14:07:31 -05001959 (1 << BH_Dirty) | (1 << BH_Uptodate));
Theodore Ts'o4f01b022011-02-26 14:07:37 -05001960 if (mpd->io_done)
1961 goto ret_extent_tail;
Theodore Ts'o8eb9e5c2011-02-26 14:07:31 -05001962 } else {
1963 /*
Theodore Ts'o4f01b022011-02-26 14:07:37 -05001964 * Page with regular buffer heads,
1965 * just add all dirty ones
Theodore Ts'o8eb9e5c2011-02-26 14:07:31 -05001966 */
1967 head = page_buffers(page);
1968 bh = head;
1969 do {
1970 BUG_ON(buffer_locked(bh));
1971 /*
1972 * We need to try to allocate
1973 * unmapped blocks in the same page.
1974 * Otherwise we won't make progress
1975 * with the page in ext4_writepage
1976 */
1977 if (ext4_bh_delay_or_unwritten(NULL, bh)) {
1978 mpage_add_bh_to_extent(mpd, logical,
1979 bh->b_size,
1980 bh->b_state);
Theodore Ts'o4f01b022011-02-26 14:07:37 -05001981 if (mpd->io_done)
1982 goto ret_extent_tail;
Theodore Ts'o8eb9e5c2011-02-26 14:07:31 -05001983 } else if (buffer_dirty(bh) && (buffer_mapped(bh))) {
1984 /*
Theodore Ts'o4f01b022011-02-26 14:07:37 -05001985 * mapped dirty buffer. We need
1986 * to update the b_state
1987 * because we look at b_state
1988 * in mpage_da_map_blocks. We
1989 * don't update b_size because
1990 * if we find an unmapped
1991 * buffer_head later we need to
1992 * use the b_state flag of that
1993 * buffer_head.
Theodore Ts'o8eb9e5c2011-02-26 14:07:31 -05001994 */
1995 if (mpd->b_size == 0)
1996 mpd->b_state = bh->b_state & BH_FLAGS;
1997 }
1998 logical++;
1999 } while ((bh = bh->b_this_page) != head);
Theodore Ts'o8e48dcf2010-05-16 18:00:00 -04002000 }
2001
2002 if (nr_to_write > 0) {
2003 nr_to_write--;
2004 if (nr_to_write == 0 &&
Theodore Ts'o4f01b022011-02-26 14:07:37 -05002005 wbc->sync_mode == WB_SYNC_NONE)
Theodore Ts'o8e48dcf2010-05-16 18:00:00 -04002006 /*
2007 * We stop writing back only if we are
2008 * not doing integrity sync. In case of
2009 * integrity sync we have to keep going
2010 * because someone may be concurrently
2011 * dirtying pages, and we might have
2012 * synced a lot of newly appeared dirty
2013 * pages, but have not synced all of the
2014 * old dirty pages.
2015 */
Theodore Ts'o4f01b022011-02-26 14:07:37 -05002016 goto out;
Theodore Ts'o8e48dcf2010-05-16 18:00:00 -04002017 }
2018 }
2019 pagevec_release(&pvec);
2020 cond_resched();
2021 }
Theodore Ts'o4f01b022011-02-26 14:07:37 -05002022 return 0;
2023ret_extent_tail:
2024 ret = MPAGE_DA_EXTENT_TAIL;
Theodore Ts'o8eb9e5c2011-02-26 14:07:31 -05002025out:
2026 pagevec_release(&pvec);
2027 cond_resched();
Theodore Ts'o8e48dcf2010-05-16 18:00:00 -04002028 return ret;
2029}
2030
2031
Alex Tomas64769242008-07-11 19:27:31 -04002032static int ext4_da_writepages(struct address_space *mapping,
Aneesh Kumar K.Va1d6cc52008-08-19 21:55:02 -04002033 struct writeback_control *wbc)
Alex Tomas64769242008-07-11 19:27:31 -04002034{
Aneesh Kumar K.V22208de2008-10-16 10:10:36 -04002035 pgoff_t index;
2036 int range_whole = 0;
Mingming Cao61628a32008-07-11 19:27:31 -04002037 handle_t *handle = NULL;
Aneesh Kumar K.Vdf222912008-09-08 23:05:34 -04002038 struct mpage_da_data mpd;
Aneesh Kumar K.V5e745b02008-08-18 18:00:57 -04002039 struct inode *inode = mapping->host;
Theodore Ts'o498e5f22008-11-05 00:14:04 -05002040 int pages_written = 0;
Theodore Ts'o55138e02009-09-29 13:31:31 -04002041 unsigned int max_pages;
Aneesh Kumar K.V2acf2c22009-02-14 10:42:58 -05002042 int range_cyclic, cycled = 1, io_done = 0;
Theodore Ts'o55138e02009-09-29 13:31:31 -04002043 int needed_blocks, ret = 0;
2044 long desired_nr_to_write, nr_to_writebump = 0;
Theodore Ts'ode89de62009-08-31 17:00:59 -04002045 loff_t range_start = wbc->range_start;
Aneesh Kumar K.V5e745b02008-08-18 18:00:57 -04002046 struct ext4_sb_info *sbi = EXT4_SB(mapping->host->i_sb);
Eric Sandeen72f84e62010-10-27 21:30:13 -04002047 pgoff_t done_index = 0;
Eric Sandeen5b41d922010-10-27 21:30:13 -04002048 pgoff_t end;
Mingming Cao61628a32008-07-11 19:27:31 -04002049
Theodore Ts'o9bffad12009-06-17 11:48:11 -04002050 trace_ext4_da_writepages(inode, wbc);
Theodore Ts'oba80b102009-01-03 20:03:21 -05002051
Mingming Cao61628a32008-07-11 19:27:31 -04002052 /*
2053 * No pages to write? This is mainly a kludge to avoid starting
2054 * a transaction for special inodes like journal inode on last iput()
2055 * because that could violate lock ordering on umount
2056 */
Aneesh Kumar K.Va1d6cc52008-08-19 21:55:02 -04002057 if (!mapping->nrpages || !mapping_tagged(mapping, PAGECACHE_TAG_DIRTY))
Mingming Cao61628a32008-07-11 19:27:31 -04002058 return 0;
Theodore Ts'o2a21e372008-11-05 09:22:24 -05002059
2060 /*
2061 * If the filesystem has aborted, it is read-only, so return
2062 * right away instead of dumping stack traces later on that
2063 * will obscure the real source of the problem. We test
Theodore Ts'o4ab2f152009-06-13 10:09:36 -04002064 * EXT4_MF_FS_ABORTED instead of sb->s_flag's MS_RDONLY because
Theodore Ts'o2a21e372008-11-05 09:22:24 -05002065 * the latter could be true if the filesystem is mounted
2066 * read-only, and in that case, ext4_da_writepages should
2067 * *never* be called, so if that ever happens, we would want
2068 * the stack trace.
2069 */
Theodore Ts'o4ab2f152009-06-13 10:09:36 -04002070 if (unlikely(sbi->s_mount_flags & EXT4_MF_FS_ABORTED))
Theodore Ts'o2a21e372008-11-05 09:22:24 -05002071 return -EROFS;
2072
Aneesh Kumar K.V22208de2008-10-16 10:10:36 -04002073 if (wbc->range_start == 0 && wbc->range_end == LLONG_MAX)
2074 range_whole = 1;
Mingming Cao61628a32008-07-11 19:27:31 -04002075
Aneesh Kumar K.V2acf2c22009-02-14 10:42:58 -05002076 range_cyclic = wbc->range_cyclic;
2077 if (wbc->range_cyclic) {
Aneesh Kumar K.V22208de2008-10-16 10:10:36 -04002078 index = mapping->writeback_index;
Aneesh Kumar K.V2acf2c22009-02-14 10:42:58 -05002079 if (index)
2080 cycled = 0;
2081 wbc->range_start = index << PAGE_CACHE_SHIFT;
2082 wbc->range_end = LLONG_MAX;
2083 wbc->range_cyclic = 0;
Eric Sandeen5b41d922010-10-27 21:30:13 -04002084 end = -1;
2085 } else {
Aneesh Kumar K.V22208de2008-10-16 10:10:36 -04002086 index = wbc->range_start >> PAGE_CACHE_SHIFT;
Eric Sandeen5b41d922010-10-27 21:30:13 -04002087 end = wbc->range_end >> PAGE_CACHE_SHIFT;
2088 }
Aneesh Kumar K.Va1d6cc52008-08-19 21:55:02 -04002089
Theodore Ts'o55138e02009-09-29 13:31:31 -04002090 /*
2091 * This works around two forms of stupidity. The first is in
2092 * the writeback code, which caps the maximum number of pages
2093 * written to be 1024 pages. This is wrong on multiple
2094 * levels; different architectues have a different page size,
2095 * which changes the maximum amount of data which gets
2096 * written. Secondly, 4 megabytes is way too small. XFS
2097 * forces this value to be 16 megabytes by multiplying
2098 * nr_to_write parameter by four, and then relies on its
2099 * allocator to allocate larger extents to make them
2100 * contiguous. Unfortunately this brings us to the second
2101 * stupidity, which is that ext4's mballoc code only allocates
2102 * at most 2048 blocks. So we force contiguous writes up to
2103 * the number of dirty blocks in the inode, or
2104 * sbi->max_writeback_mb_bump whichever is smaller.
2105 */
2106 max_pages = sbi->s_max_writeback_mb_bump << (20 - PAGE_CACHE_SHIFT);
Eric Sandeenb443e732010-10-27 21:30:03 -04002107 if (!range_cyclic && range_whole) {
2108 if (wbc->nr_to_write == LONG_MAX)
2109 desired_nr_to_write = wbc->nr_to_write;
2110 else
2111 desired_nr_to_write = wbc->nr_to_write * 8;
2112 } else
Theodore Ts'o55138e02009-09-29 13:31:31 -04002113 desired_nr_to_write = ext4_num_dirty_pages(inode, index,
2114 max_pages);
2115 if (desired_nr_to_write > max_pages)
2116 desired_nr_to_write = max_pages;
2117
2118 if (wbc->nr_to_write < desired_nr_to_write) {
2119 nr_to_writebump = desired_nr_to_write - wbc->nr_to_write;
2120 wbc->nr_to_write = desired_nr_to_write;
2121 }
2122
Aneesh Kumar K.V2acf2c22009-02-14 10:42:58 -05002123retry:
Wu Fengguang6e6938b2010-06-06 10:38:15 -06002124 if (wbc->sync_mode == WB_SYNC_ALL || wbc->tagged_writepages)
Eric Sandeen5b41d922010-10-27 21:30:13 -04002125 tag_pages_for_writeback(mapping, index, end);
2126
Aneesh Kumar K.V22208de2008-10-16 10:10:36 -04002127 while (!ret && wbc->nr_to_write > 0) {
Aneesh Kumar K.Va1d6cc52008-08-19 21:55:02 -04002128
2129 /*
2130 * we insert one extent at a time. So we need
2131 * credit needed for single extent allocation.
2132 * journalled mode is currently not supported
2133 * by delalloc
2134 */
2135 BUG_ON(ext4_should_journal_data(inode));
Mingming Cao525f4ed2008-08-19 22:15:58 -04002136 needed_blocks = ext4_da_writepages_trans_blocks(inode);
Aneesh Kumar K.Va1d6cc52008-08-19 21:55:02 -04002137
Mingming Cao61628a32008-07-11 19:27:31 -04002138 /* start a new transaction*/
2139 handle = ext4_journal_start(inode, needed_blocks);
2140 if (IS_ERR(handle)) {
2141 ret = PTR_ERR(handle);
Theodore Ts'o16939182009-09-26 17:43:59 -04002142 ext4_msg(inode->i_sb, KERN_CRIT, "%s: jbd2_start: "
Curt Wohlgemuthfbe845d2010-05-16 13:00:00 -04002143 "%ld pages, ino %lu; err %d", __func__,
Aneesh Kumar K.Va1d6cc52008-08-19 21:55:02 -04002144 wbc->nr_to_write, inode->i_ino, ret);
Mingming Cao61628a32008-07-11 19:27:31 -04002145 goto out_writepages;
2146 }
Theodore Ts'of63e6002009-02-23 16:42:39 -05002147
2148 /*
Theodore Ts'o8eb9e5c2011-02-26 14:07:31 -05002149 * Now call write_cache_pages_da() to find the next
Theodore Ts'of63e6002009-02-23 16:42:39 -05002150 * contiguous region of logical blocks that need
Theodore Ts'o8eb9e5c2011-02-26 14:07:31 -05002151 * blocks to be allocated by ext4 and submit them.
Theodore Ts'of63e6002009-02-23 16:42:39 -05002152 */
Eric Sandeen72f84e62010-10-27 21:30:13 -04002153 ret = write_cache_pages_da(mapping, wbc, &mpd, &done_index);
Theodore Ts'of63e6002009-02-23 16:42:39 -05002154 /*
André Goddard Rosaaf901ca2009-11-14 13:09:05 -02002155 * If we have a contiguous extent of pages and we
Theodore Ts'of63e6002009-02-23 16:42:39 -05002156 * haven't done the I/O yet, map the blocks and submit
2157 * them for I/O.
2158 */
2159 if (!mpd.io_done && mpd.next_page != mpd.first_page) {
Theodore Ts'o5a87b7a2010-10-27 21:30:09 -04002160 mpage_da_map_and_submit(&mpd);
Theodore Ts'of63e6002009-02-23 16:42:39 -05002161 ret = MPAGE_DA_EXTENT_TAIL;
2162 }
Theodore Ts'ob3a3ca82009-08-31 23:13:11 -04002163 trace_ext4_da_write_pages(inode, &mpd);
Theodore Ts'of63e6002009-02-23 16:42:39 -05002164 wbc->nr_to_write -= mpd.pages_written;
Aneesh Kumar K.Vdf222912008-09-08 23:05:34 -04002165
Mingming Cao61628a32008-07-11 19:27:31 -04002166 ext4_journal_stop(handle);
Aneesh Kumar K.Vdf222912008-09-08 23:05:34 -04002167
Eric Sandeen8f64b322009-02-26 00:57:35 -05002168 if ((mpd.retval == -ENOSPC) && sbi->s_journal) {
Aneesh Kumar K.V22208de2008-10-16 10:10:36 -04002169 /* commit the transaction which would
2170 * free blocks released in the transaction
2171 * and try again
2172 */
Aneesh Kumar K.Vdf222912008-09-08 23:05:34 -04002173 jbd2_journal_force_commit_nested(sbi->s_journal);
Aneesh Kumar K.V22208de2008-10-16 10:10:36 -04002174 ret = 0;
2175 } else if (ret == MPAGE_DA_EXTENT_TAIL) {
Aneesh Kumar K.Va1d6cc52008-08-19 21:55:02 -04002176 /*
2177 * got one extent now try with
2178 * rest of the pages
2179 */
Aneesh Kumar K.V22208de2008-10-16 10:10:36 -04002180 pages_written += mpd.pages_written;
Aneesh Kumar K.Va1d6cc52008-08-19 21:55:02 -04002181 ret = 0;
Aneesh Kumar K.V2acf2c22009-02-14 10:42:58 -05002182 io_done = 1;
Aneesh Kumar K.V22208de2008-10-16 10:10:36 -04002183 } else if (wbc->nr_to_write)
Mingming Cao61628a32008-07-11 19:27:31 -04002184 /*
2185 * There is no more writeout needed
2186 * or we requested for a noblocking writeout
2187 * and we found the device congested
2188 */
Mingming Cao61628a32008-07-11 19:27:31 -04002189 break;
Mingming Cao61628a32008-07-11 19:27:31 -04002190 }
Aneesh Kumar K.V2acf2c22009-02-14 10:42:58 -05002191 if (!io_done && !cycled) {
2192 cycled = 1;
2193 index = 0;
2194 wbc->range_start = index << PAGE_CACHE_SHIFT;
2195 wbc->range_end = mapping->writeback_index - 1;
2196 goto retry;
2197 }
Mingming Cao61628a32008-07-11 19:27:31 -04002198
Aneesh Kumar K.V22208de2008-10-16 10:10:36 -04002199 /* Update index */
Aneesh Kumar K.V2acf2c22009-02-14 10:42:58 -05002200 wbc->range_cyclic = range_cyclic;
Aneesh Kumar K.V22208de2008-10-16 10:10:36 -04002201 if (wbc->range_cyclic || (range_whole && wbc->nr_to_write > 0))
2202 /*
2203 * set the writeback_index so that range_cyclic
2204 * mode will write it back later
2205 */
Eric Sandeen72f84e62010-10-27 21:30:13 -04002206 mapping->writeback_index = done_index;
Aneesh Kumar K.Va1d6cc52008-08-19 21:55:02 -04002207
Mingming Cao61628a32008-07-11 19:27:31 -04002208out_writepages:
Richard Kennedy2faf2e12009-12-25 15:46:07 -05002209 wbc->nr_to_write -= nr_to_writebump;
Theodore Ts'ode89de62009-08-31 17:00:59 -04002210 wbc->range_start = range_start;
Theodore Ts'o9bffad12009-06-17 11:48:11 -04002211 trace_ext4_da_writepages_result(inode, wbc, ret, pages_written);
Mingming Cao61628a32008-07-11 19:27:31 -04002212 return ret;
Alex Tomas64769242008-07-11 19:27:31 -04002213}
2214
Aneesh Kumar K.V79f0be82008-10-08 23:13:30 -04002215#define FALL_BACK_TO_NONDELALLOC 1
2216static int ext4_nonda_switch(struct super_block *sb)
2217{
2218 s64 free_blocks, dirty_blocks;
2219 struct ext4_sb_info *sbi = EXT4_SB(sb);
2220
2221 /*
2222 * switch to non delalloc mode if we are running low
2223 * on free block. The free block accounting via percpu
Eric Dumazet179f7eb2009-01-06 14:41:04 -08002224 * counters can get slightly wrong with percpu_counter_batch getting
Aneesh Kumar K.V79f0be82008-10-08 23:13:30 -04002225 * accumulated on each CPU without updating global counters
2226 * Delalloc need an accurate free block accounting. So switch
2227 * to non delalloc when we are near to error range.
2228 */
2229 free_blocks = percpu_counter_read_positive(&sbi->s_freeblocks_counter);
2230 dirty_blocks = percpu_counter_read_positive(&sbi->s_dirtyblocks_counter);
2231 if (2 * free_blocks < 3 * dirty_blocks ||
2232 free_blocks < (dirty_blocks + EXT4_FREEBLOCKS_WATERMARK)) {
2233 /*
Eric Sandeenc8afb442009-12-23 07:58:12 -05002234 * free block count is less than 150% of dirty blocks
2235 * or free blocks is less than watermark
Aneesh Kumar K.V79f0be82008-10-08 23:13:30 -04002236 */
2237 return 1;
2238 }
Eric Sandeenc8afb442009-12-23 07:58:12 -05002239 /*
2240 * Even if we don't switch but are nearing capacity,
2241 * start pushing delalloc when 1/2 of free blocks are dirty.
2242 */
2243 if (free_blocks < 2 * dirty_blocks)
2244 writeback_inodes_sb_if_idle(sb);
2245
Aneesh Kumar K.V79f0be82008-10-08 23:13:30 -04002246 return 0;
2247}
2248
Alex Tomas64769242008-07-11 19:27:31 -04002249static int ext4_da_write_begin(struct file *file, struct address_space *mapping,
Theodore Ts'ode9a55b2009-06-14 17:45:34 -04002250 loff_t pos, unsigned len, unsigned flags,
2251 struct page **pagep, void **fsdata)
Alex Tomas64769242008-07-11 19:27:31 -04002252{
Eric Sandeen72b8ab92010-05-16 11:00:00 -04002253 int ret, retries = 0;
Alex Tomas64769242008-07-11 19:27:31 -04002254 struct page *page;
2255 pgoff_t index;
Alex Tomas64769242008-07-11 19:27:31 -04002256 struct inode *inode = mapping->host;
2257 handle_t *handle;
2258
2259 index = pos >> PAGE_CACHE_SHIFT;
Aneesh Kumar K.V79f0be82008-10-08 23:13:30 -04002260
2261 if (ext4_nonda_switch(inode->i_sb)) {
2262 *fsdata = (void *)FALL_BACK_TO_NONDELALLOC;
2263 return ext4_write_begin(file, mapping, pos,
2264 len, flags, pagep, fsdata);
2265 }
2266 *fsdata = (void *)0;
Theodore Ts'o9bffad12009-06-17 11:48:11 -04002267 trace_ext4_da_write_begin(inode, pos, len, flags);
Mingming Caod2a17632008-07-14 17:52:37 -04002268retry:
Alex Tomas64769242008-07-11 19:27:31 -04002269 /*
2270 * With delayed allocation, we don't log the i_disksize update
2271 * if there is delayed block allocation. But we still need
2272 * to journalling the i_disksize update if writes to the end
2273 * of file which has an already mapped buffer.
2274 */
2275 handle = ext4_journal_start(inode, 1);
2276 if (IS_ERR(handle)) {
2277 ret = PTR_ERR(handle);
2278 goto out;
2279 }
Jan Karaebd36102009-02-22 21:09:59 -05002280 /* We cannot recurse into the filesystem as the transaction is already
2281 * started */
2282 flags |= AOP_FLAG_NOFS;
Alex Tomas64769242008-07-11 19:27:31 -04002283
Nick Piggin54566b22009-01-04 12:00:53 -08002284 page = grab_cache_page_write_begin(mapping, index, flags);
Eric Sandeend5a0d4f2008-08-02 18:51:06 -04002285 if (!page) {
2286 ext4_journal_stop(handle);
2287 ret = -ENOMEM;
2288 goto out;
2289 }
Alex Tomas64769242008-07-11 19:27:31 -04002290 *pagep = page;
2291
Christoph Hellwig6e1db882010-06-04 11:29:57 +02002292 ret = __block_write_begin(page, pos, len, ext4_da_get_block_prep);
Alex Tomas64769242008-07-11 19:27:31 -04002293 if (ret < 0) {
2294 unlock_page(page);
2295 ext4_journal_stop(handle);
2296 page_cache_release(page);
Aneesh Kumar K.Vae4d5372008-09-13 13:10:25 -04002297 /*
2298 * block_write_begin may have instantiated a few blocks
2299 * outside i_size. Trim these off again. Don't need
2300 * i_size_read because we hold i_mutex.
2301 */
2302 if (pos + len > inode->i_size)
Jan Karab9a42072009-12-08 21:24:33 -05002303 ext4_truncate_failed_write(inode);
Alex Tomas64769242008-07-11 19:27:31 -04002304 }
2305
Mingming Caod2a17632008-07-14 17:52:37 -04002306 if (ret == -ENOSPC && ext4_should_retry_alloc(inode->i_sb, &retries))
2307 goto retry;
Alex Tomas64769242008-07-11 19:27:31 -04002308out:
2309 return ret;
2310}
2311
Mingming Cao632eaea2008-07-11 19:27:31 -04002312/*
2313 * Check if we should update i_disksize
2314 * when write to the end of file but not require block allocation
2315 */
2316static int ext4_da_should_update_i_disksize(struct page *page,
Theodore Ts'ode9a55b2009-06-14 17:45:34 -04002317 unsigned long offset)
Mingming Cao632eaea2008-07-11 19:27:31 -04002318{
2319 struct buffer_head *bh;
2320 struct inode *inode = page->mapping->host;
2321 unsigned int idx;
2322 int i;
2323
2324 bh = page_buffers(page);
2325 idx = offset >> inode->i_blkbits;
2326
Theodore Ts'oaf5bc922008-09-08 22:25:24 -04002327 for (i = 0; i < idx; i++)
Mingming Cao632eaea2008-07-11 19:27:31 -04002328 bh = bh->b_this_page;
2329
Aneesh Kumar K.V29fa89d2009-05-12 16:30:27 -04002330 if (!buffer_mapped(bh) || (buffer_delay(bh)) || buffer_unwritten(bh))
Mingming Cao632eaea2008-07-11 19:27:31 -04002331 return 0;
2332 return 1;
2333}
2334
Alex Tomas64769242008-07-11 19:27:31 -04002335static int ext4_da_write_end(struct file *file,
Theodore Ts'ode9a55b2009-06-14 17:45:34 -04002336 struct address_space *mapping,
2337 loff_t pos, unsigned len, unsigned copied,
2338 struct page *page, void *fsdata)
Alex Tomas64769242008-07-11 19:27:31 -04002339{
2340 struct inode *inode = mapping->host;
2341 int ret = 0, ret2;
2342 handle_t *handle = ext4_journal_current_handle();
2343 loff_t new_i_size;
Mingming Cao632eaea2008-07-11 19:27:31 -04002344 unsigned long start, end;
Aneesh Kumar K.V79f0be82008-10-08 23:13:30 -04002345 int write_mode = (int)(unsigned long)fsdata;
2346
2347 if (write_mode == FALL_BACK_TO_NONDELALLOC) {
2348 if (ext4_should_order_data(inode)) {
2349 return ext4_ordered_write_end(file, mapping, pos,
2350 len, copied, page, fsdata);
2351 } else if (ext4_should_writeback_data(inode)) {
2352 return ext4_writeback_write_end(file, mapping, pos,
2353 len, copied, page, fsdata);
2354 } else {
2355 BUG();
2356 }
2357 }
Mingming Cao632eaea2008-07-11 19:27:31 -04002358
Theodore Ts'o9bffad12009-06-17 11:48:11 -04002359 trace_ext4_da_write_end(inode, pos, len, copied);
Mingming Cao632eaea2008-07-11 19:27:31 -04002360 start = pos & (PAGE_CACHE_SIZE - 1);
Theodore Ts'oaf5bc922008-09-08 22:25:24 -04002361 end = start + copied - 1;
Alex Tomas64769242008-07-11 19:27:31 -04002362
2363 /*
2364 * generic_write_end() will run mark_inode_dirty() if i_size
2365 * changes. So let's piggyback the i_disksize mark_inode_dirty
2366 * into that.
2367 */
2368
2369 new_i_size = pos + copied;
Mingming Cao632eaea2008-07-11 19:27:31 -04002370 if (new_i_size > EXT4_I(inode)->i_disksize) {
2371 if (ext4_da_should_update_i_disksize(page, end)) {
2372 down_write(&EXT4_I(inode)->i_data_sem);
2373 if (new_i_size > EXT4_I(inode)->i_disksize) {
2374 /*
2375 * Updating i_disksize when extending file
2376 * without needing block allocation
2377 */
2378 if (ext4_should_order_data(inode))
2379 ret = ext4_jbd2_file_inode(handle,
2380 inode);
Alex Tomas64769242008-07-11 19:27:31 -04002381
Mingming Cao632eaea2008-07-11 19:27:31 -04002382 EXT4_I(inode)->i_disksize = new_i_size;
2383 }
2384 up_write(&EXT4_I(inode)->i_data_sem);
Aneesh Kumar K.Vcf17fea2008-09-13 13:06:18 -04002385 /* We need to mark inode dirty even if
2386 * new_i_size is less that inode->i_size
2387 * bu greater than i_disksize.(hint delalloc)
2388 */
2389 ext4_mark_inode_dirty(handle, inode);
Alex Tomas64769242008-07-11 19:27:31 -04002390 }
Mingming Cao632eaea2008-07-11 19:27:31 -04002391 }
Alex Tomas64769242008-07-11 19:27:31 -04002392 ret2 = generic_write_end(file, mapping, pos, len, copied,
2393 page, fsdata);
2394 copied = ret2;
2395 if (ret2 < 0)
2396 ret = ret2;
2397 ret2 = ext4_journal_stop(handle);
2398 if (!ret)
2399 ret = ret2;
2400
2401 return ret ? ret : copied;
2402}
2403
2404static void ext4_da_invalidatepage(struct page *page, unsigned long offset)
2405{
Alex Tomas64769242008-07-11 19:27:31 -04002406 /*
2407 * Drop reserved blocks
2408 */
2409 BUG_ON(!PageLocked(page));
2410 if (!page_has_buffers(page))
2411 goto out;
2412
Mingming Caod2a17632008-07-14 17:52:37 -04002413 ext4_da_page_release_reservation(page, offset);
Alex Tomas64769242008-07-11 19:27:31 -04002414
2415out:
2416 ext4_invalidatepage(page, offset);
2417
2418 return;
2419}
2420
Theodore Ts'occd25062009-02-26 01:04:07 -05002421/*
2422 * Force all delayed allocation blocks to be allocated for a given inode.
2423 */
2424int ext4_alloc_da_blocks(struct inode *inode)
2425{
Theodore Ts'ofb40ba02009-09-16 19:30:40 -04002426 trace_ext4_alloc_da_blocks(inode);
2427
Theodore Ts'occd25062009-02-26 01:04:07 -05002428 if (!EXT4_I(inode)->i_reserved_data_blocks &&
2429 !EXT4_I(inode)->i_reserved_meta_blocks)
2430 return 0;
2431
2432 /*
2433 * We do something simple for now. The filemap_flush() will
2434 * also start triggering a write of the data blocks, which is
2435 * not strictly speaking necessary (and for users of
2436 * laptop_mode, not even desirable). However, to do otherwise
2437 * would require replicating code paths in:
Theodore Ts'ode9a55b2009-06-14 17:45:34 -04002438 *
Theodore Ts'occd25062009-02-26 01:04:07 -05002439 * ext4_da_writepages() ->
2440 * write_cache_pages() ---> (via passed in callback function)
2441 * __mpage_da_writepage() -->
2442 * mpage_add_bh_to_extent()
2443 * mpage_da_map_blocks()
2444 *
2445 * The problem is that write_cache_pages(), located in
2446 * mm/page-writeback.c, marks pages clean in preparation for
2447 * doing I/O, which is not desirable if we're not planning on
2448 * doing I/O at all.
2449 *
2450 * We could call write_cache_pages(), and then redirty all of
Wu Fengguang380cf092010-11-11 19:23:29 +08002451 * the pages by calling redirty_page_for_writepage() but that
Theodore Ts'occd25062009-02-26 01:04:07 -05002452 * would be ugly in the extreme. So instead we would need to
2453 * replicate parts of the code in the above functions,
Lucas De Marchi25985ed2011-03-30 22:57:33 -03002454 * simplifying them because we wouldn't actually intend to
Theodore Ts'occd25062009-02-26 01:04:07 -05002455 * write out the pages, but rather only collect contiguous
2456 * logical block extents, call the multi-block allocator, and
2457 * then update the buffer heads with the block allocations.
Theodore Ts'ode9a55b2009-06-14 17:45:34 -04002458 *
Theodore Ts'occd25062009-02-26 01:04:07 -05002459 * For now, though, we'll cheat by calling filemap_flush(),
2460 * which will map the blocks, and start the I/O, but not
2461 * actually wait for the I/O to complete.
2462 */
2463 return filemap_flush(inode->i_mapping);
2464}
Alex Tomas64769242008-07-11 19:27:31 -04002465
2466/*
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002467 * bmap() is special. It gets used by applications such as lilo and by
2468 * the swapper to find the on-disk block of a specific piece of data.
2469 *
2470 * Naturally, this is dangerous if the block concerned is still in the
Mingming Cao617ba132006-10-11 01:20:53 -07002471 * journal. If somebody makes a swapfile on an ext4 data-journaling
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002472 * filesystem and enables swap, then they may get a nasty shock when the
2473 * data getting swapped to that swapfile suddenly gets overwritten by
2474 * the original zero's written out previously to the journal and
2475 * awaiting writeback in the kernel's buffer cache.
2476 *
2477 * So, if we see any bmap calls here on a modified, data-journaled file,
2478 * take extra steps to flush any blocks which might be in the cache.
2479 */
Mingming Cao617ba132006-10-11 01:20:53 -07002480static sector_t ext4_bmap(struct address_space *mapping, sector_t block)
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002481{
2482 struct inode *inode = mapping->host;
2483 journal_t *journal;
2484 int err;
2485
Alex Tomas64769242008-07-11 19:27:31 -04002486 if (mapping_tagged(mapping, PAGECACHE_TAG_DIRTY) &&
2487 test_opt(inode->i_sb, DELALLOC)) {
2488 /*
2489 * With delalloc we want to sync the file
2490 * so that we can make sure we allocate
2491 * blocks for file
2492 */
2493 filemap_write_and_wait(mapping);
2494 }
2495
Theodore Ts'o19f5fb72010-01-24 14:34:07 -05002496 if (EXT4_JOURNAL(inode) &&
2497 ext4_test_inode_state(inode, EXT4_STATE_JDATA)) {
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002498 /*
2499 * This is a REALLY heavyweight approach, but the use of
2500 * bmap on dirty files is expected to be extremely rare:
2501 * only if we run lilo or swapon on a freshly made file
2502 * do we expect this to happen.
2503 *
2504 * (bmap requires CAP_SYS_RAWIO so this does not
2505 * represent an unprivileged user DOS attack --- we'd be
2506 * in trouble if mortal users could trigger this path at
2507 * will.)
2508 *
Mingming Cao617ba132006-10-11 01:20:53 -07002509 * NB. EXT4_STATE_JDATA is not set on files other than
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002510 * regular files. If somebody wants to bmap a directory
2511 * or symlink and gets confused because the buffer
2512 * hasn't yet been flushed to disk, they deserve
2513 * everything they get.
2514 */
2515
Theodore Ts'o19f5fb72010-01-24 14:34:07 -05002516 ext4_clear_inode_state(inode, EXT4_STATE_JDATA);
Mingming Cao617ba132006-10-11 01:20:53 -07002517 journal = EXT4_JOURNAL(inode);
Mingming Caodab291a2006-10-11 01:21:01 -07002518 jbd2_journal_lock_updates(journal);
2519 err = jbd2_journal_flush(journal);
2520 jbd2_journal_unlock_updates(journal);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002521
2522 if (err)
2523 return 0;
2524 }
2525
Theodore Ts'oaf5bc922008-09-08 22:25:24 -04002526 return generic_block_bmap(mapping, block, ext4_get_block);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002527}
2528
Mingming Cao617ba132006-10-11 01:20:53 -07002529static int ext4_readpage(struct file *file, struct page *page)
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002530{
Jiaying Zhang0562e0b2011-03-21 21:38:05 -04002531 trace_ext4_readpage(page);
Mingming Cao617ba132006-10-11 01:20:53 -07002532 return mpage_readpage(page, ext4_get_block);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002533}
2534
2535static int
Mingming Cao617ba132006-10-11 01:20:53 -07002536ext4_readpages(struct file *file, struct address_space *mapping,
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002537 struct list_head *pages, unsigned nr_pages)
2538{
Mingming Cao617ba132006-10-11 01:20:53 -07002539 return mpage_readpages(mapping, pages, nr_pages, ext4_get_block);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002540}
2541
Jiaying Zhang744692d2010-03-04 16:14:02 -05002542static void ext4_invalidatepage_free_endio(struct page *page, unsigned long offset)
2543{
2544 struct buffer_head *head, *bh;
2545 unsigned int curr_off = 0;
2546
2547 if (!page_has_buffers(page))
2548 return;
2549 head = bh = page_buffers(page);
2550 do {
2551 if (offset <= curr_off && test_clear_buffer_uninit(bh)
2552 && bh->b_private) {
2553 ext4_free_io_end(bh->b_private);
2554 bh->b_private = NULL;
2555 bh->b_end_io = NULL;
2556 }
2557 curr_off = curr_off + bh->b_size;
2558 bh = bh->b_this_page;
2559 } while (bh != head);
2560}
2561
Mingming Cao617ba132006-10-11 01:20:53 -07002562static void ext4_invalidatepage(struct page *page, unsigned long offset)
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002563{
Mingming Cao617ba132006-10-11 01:20:53 -07002564 journal_t *journal = EXT4_JOURNAL(page->mapping->host);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002565
Jiaying Zhang0562e0b2011-03-21 21:38:05 -04002566 trace_ext4_invalidatepage(page, offset);
2567
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002568 /*
Jiaying Zhang744692d2010-03-04 16:14:02 -05002569 * free any io_end structure allocated for buffers to be discarded
2570 */
2571 if (ext4_should_dioread_nolock(page->mapping->host))
2572 ext4_invalidatepage_free_endio(page, offset);
2573 /*
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002574 * If it's a full truncate we just forget about the pending dirtying
2575 */
2576 if (offset == 0)
2577 ClearPageChecked(page);
2578
Frank Mayhar03901312009-01-07 00:06:22 -05002579 if (journal)
2580 jbd2_journal_invalidatepage(journal, page, offset);
2581 else
2582 block_invalidatepage(page, offset);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002583}
2584
Mingming Cao617ba132006-10-11 01:20:53 -07002585static int ext4_releasepage(struct page *page, gfp_t wait)
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002586{
Mingming Cao617ba132006-10-11 01:20:53 -07002587 journal_t *journal = EXT4_JOURNAL(page->mapping->host);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002588
Jiaying Zhang0562e0b2011-03-21 21:38:05 -04002589 trace_ext4_releasepage(page);
2590
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002591 WARN_ON(PageChecked(page));
2592 if (!page_has_buffers(page))
2593 return 0;
Frank Mayhar03901312009-01-07 00:06:22 -05002594 if (journal)
2595 return jbd2_journal_try_to_free_buffers(journal, page, wait);
2596 else
2597 return try_to_free_buffers(page);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002598}
2599
2600/*
Theodore Ts'o2ed88682010-05-16 20:00:00 -04002601 * ext4_get_block used when preparing for a DIO write or buffer write.
2602 * We allocate an uinitialized extent if blocks haven't been allocated.
2603 * The extent will be converted to initialized after the IO is complete.
2604 */
Jiaying Zhangc7064ef2010-03-02 13:28:44 -05002605static int ext4_get_block_write(struct inode *inode, sector_t iblock,
Mingming Cao4c0425f2009-09-28 15:48:41 -04002606 struct buffer_head *bh_result, int create)
2607{
Jiaying Zhangc7064ef2010-03-02 13:28:44 -05002608 ext4_debug("ext4_get_block_write: inode %lu, create flag %d\n",
Mingming Cao8d5d02e2009-09-28 15:48:29 -04002609 inode->i_ino, create);
Theodore Ts'o2ed88682010-05-16 20:00:00 -04002610 return _ext4_get_block(inode, iblock, bh_result,
2611 EXT4_GET_BLOCKS_IO_CREATE_EXT);
Mingming Cao4c0425f2009-09-28 15:48:41 -04002612}
2613
Mingming Cao4c0425f2009-09-28 15:48:41 -04002614static void ext4_end_io_dio(struct kiocb *iocb, loff_t offset,
Christoph Hellwig552ef802010-07-27 11:56:06 -04002615 ssize_t size, void *private, int ret,
2616 bool is_async)
Mingming Cao4c0425f2009-09-28 15:48:41 -04002617{
Christoph Hellwig72c50522011-06-24 14:29:48 -04002618 struct inode *inode = iocb->ki_filp->f_path.dentry->d_inode;
Mingming Cao4c0425f2009-09-28 15:48:41 -04002619 ext4_io_end_t *io_end = iocb->private;
2620 struct workqueue_struct *wq;
Jiaying Zhang744692d2010-03-04 16:14:02 -05002621 unsigned long flags;
2622 struct ext4_inode_info *ei;
Mingming Cao4c0425f2009-09-28 15:48:41 -04002623
Mingming4b70df12009-11-03 14:44:54 -05002624 /* if not async direct IO or dio with 0 bytes write, just return */
2625 if (!io_end || !size)
Christoph Hellwig552ef802010-07-27 11:56:06 -04002626 goto out;
Mingming4b70df12009-11-03 14:44:54 -05002627
Mingming Cao8d5d02e2009-09-28 15:48:29 -04002628 ext_debug("ext4_end_io_dio(): io_end 0x%p"
2629 "for inode %lu, iocb 0x%p, offset %llu, size %llu\n",
2630 iocb->private, io_end->inode->i_ino, iocb, offset,
2631 size);
Mingming Cao8d5d02e2009-09-28 15:48:29 -04002632
2633 /* if not aio dio with unwritten extents, just free io and return */
Theodore Ts'obd2d0212010-10-27 21:30:10 -04002634 if (!(io_end->flag & EXT4_IO_END_UNWRITTEN)) {
Mingming Cao8d5d02e2009-09-28 15:48:29 -04002635 ext4_free_io_end(io_end);
2636 iocb->private = NULL;
jiayingz@google.com (Jiaying Zhang)5b3ff232010-07-27 11:56:06 -04002637out:
2638 if (is_async)
2639 aio_complete(iocb, ret, 0);
Christoph Hellwig72c50522011-06-24 14:29:48 -04002640 inode_dio_done(inode);
jiayingz@google.com (Jiaying Zhang)5b3ff232010-07-27 11:56:06 -04002641 return;
Mingming Cao8d5d02e2009-09-28 15:48:29 -04002642 }
2643
Mingming Cao4c0425f2009-09-28 15:48:41 -04002644 io_end->offset = offset;
2645 io_end->size = size;
jiayingz@google.com (Jiaying Zhang)5b3ff232010-07-27 11:56:06 -04002646 if (is_async) {
2647 io_end->iocb = iocb;
2648 io_end->result = ret;
2649 }
Mingming Cao4c0425f2009-09-28 15:48:41 -04002650 wq = EXT4_SB(io_end->inode->i_sb)->dio_unwritten_wq;
2651
Mingming Cao8d5d02e2009-09-28 15:48:29 -04002652 /* Add the io_end to per-inode completed aio dio list*/
Jiaying Zhang744692d2010-03-04 16:14:02 -05002653 ei = EXT4_I(io_end->inode);
2654 spin_lock_irqsave(&ei->i_completed_io_lock, flags);
2655 list_add_tail(&io_end->list, &ei->i_completed_io_list);
2656 spin_unlock_irqrestore(&ei->i_completed_io_lock, flags);
Eric Sandeenc999af22010-10-27 21:30:07 -04002657
2658 /* queue the work to convert unwritten extents to written */
2659 queue_work(wq, &io_end->work);
Mingming Cao4c0425f2009-09-28 15:48:41 -04002660 iocb->private = NULL;
Christoph Hellwig72c50522011-06-24 14:29:48 -04002661
2662 /* XXX: probably should move into the real I/O completion handler */
2663 inode_dio_done(inode);
Mingming Cao4c0425f2009-09-28 15:48:41 -04002664}
Jiaying Zhangc7064ef2010-03-02 13:28:44 -05002665
Jiaying Zhang744692d2010-03-04 16:14:02 -05002666static void ext4_end_io_buffer_write(struct buffer_head *bh, int uptodate)
2667{
2668 ext4_io_end_t *io_end = bh->b_private;
2669 struct workqueue_struct *wq;
2670 struct inode *inode;
2671 unsigned long flags;
2672
2673 if (!test_clear_buffer_uninit(bh) || !io_end)
2674 goto out;
2675
2676 if (!(io_end->inode->i_sb->s_flags & MS_ACTIVE)) {
2677 printk("sb umounted, discard end_io request for inode %lu\n",
2678 io_end->inode->i_ino);
2679 ext4_free_io_end(io_end);
2680 goto out;
2681 }
2682
Tao Ma32c80b32011-08-13 12:30:59 -04002683 /*
2684 * It may be over-defensive here to check EXT4_IO_END_UNWRITTEN now,
2685 * but being more careful is always safe for the future change.
2686 */
Jiaying Zhang744692d2010-03-04 16:14:02 -05002687 inode = io_end->inode;
Tao Ma32c80b32011-08-13 12:30:59 -04002688 if (!(io_end->flag & EXT4_IO_END_UNWRITTEN)) {
2689 io_end->flag |= EXT4_IO_END_UNWRITTEN;
2690 atomic_inc(&EXT4_I(inode)->i_aiodio_unwritten);
2691 }
Jiaying Zhang744692d2010-03-04 16:14:02 -05002692
2693 /* Add the io_end to per-inode completed io list*/
2694 spin_lock_irqsave(&EXT4_I(inode)->i_completed_io_lock, flags);
2695 list_add_tail(&io_end->list, &EXT4_I(inode)->i_completed_io_list);
2696 spin_unlock_irqrestore(&EXT4_I(inode)->i_completed_io_lock, flags);
2697
2698 wq = EXT4_SB(inode->i_sb)->dio_unwritten_wq;
2699 /* queue the work to convert unwritten extents to written */
2700 queue_work(wq, &io_end->work);
2701out:
2702 bh->b_private = NULL;
2703 bh->b_end_io = NULL;
2704 clear_buffer_uninit(bh);
2705 end_buffer_async_write(bh, uptodate);
2706}
2707
2708static int ext4_set_bh_endio(struct buffer_head *bh, struct inode *inode)
2709{
2710 ext4_io_end_t *io_end;
2711 struct page *page = bh->b_page;
2712 loff_t offset = (sector_t)page->index << PAGE_CACHE_SHIFT;
2713 size_t size = bh->b_size;
2714
2715retry:
2716 io_end = ext4_init_io_end(inode, GFP_ATOMIC);
2717 if (!io_end) {
Andrew Morton6db26ff2011-01-12 16:59:13 -08002718 pr_warn_ratelimited("%s: allocation fail\n", __func__);
Jiaying Zhang744692d2010-03-04 16:14:02 -05002719 schedule();
2720 goto retry;
2721 }
2722 io_end->offset = offset;
2723 io_end->size = size;
2724 /*
2725 * We need to hold a reference to the page to make sure it
2726 * doesn't get evicted before ext4_end_io_work() has a chance
2727 * to convert the extent from written to unwritten.
2728 */
2729 io_end->page = page;
2730 get_page(io_end->page);
2731
2732 bh->b_private = io_end;
2733 bh->b_end_io = ext4_end_io_buffer_write;
2734 return 0;
2735}
2736
Mingming Cao4c0425f2009-09-28 15:48:41 -04002737/*
2738 * For ext4 extent files, ext4 will do direct-io write to holes,
2739 * preallocated extents, and those write extend the file, no need to
2740 * fall back to buffered IO.
2741 *
Uwe Kleine-Königb5950762010-11-01 15:38:34 -04002742 * For holes, we fallocate those blocks, mark them as uninitialized
Mingming Cao4c0425f2009-09-28 15:48:41 -04002743 * If those blocks were preallocated, we mark sure they are splited, but
Uwe Kleine-Königb5950762010-11-01 15:38:34 -04002744 * still keep the range to write as uninitialized.
Mingming Cao4c0425f2009-09-28 15:48:41 -04002745 *
Mingming Cao8d5d02e2009-09-28 15:48:29 -04002746 * The unwrritten extents will be converted to written when DIO is completed.
2747 * For async direct IO, since the IO may still pending when return, we
Lucas De Marchi25985ed2011-03-30 22:57:33 -03002748 * set up an end_io call back function, which will do the conversion
Mingming Cao8d5d02e2009-09-28 15:48:29 -04002749 * when async direct IO completed.
Mingming Cao4c0425f2009-09-28 15:48:41 -04002750 *
2751 * If the O_DIRECT write will extend the file then add this inode to the
2752 * orphan list. So recovery will truncate it back to the original size
2753 * if the machine crashes during the write.
2754 *
2755 */
2756static ssize_t ext4_ext_direct_IO(int rw, struct kiocb *iocb,
2757 const struct iovec *iov, loff_t offset,
2758 unsigned long nr_segs)
2759{
2760 struct file *file = iocb->ki_filp;
2761 struct inode *inode = file->f_mapping->host;
2762 ssize_t ret;
2763 size_t count = iov_length(iov, nr_segs);
2764
2765 loff_t final_size = offset + count;
2766 if (rw == WRITE && final_size <= inode->i_size) {
2767 /*
Mingming Cao8d5d02e2009-09-28 15:48:29 -04002768 * We could direct write to holes and fallocate.
2769 *
2770 * Allocated blocks to fill the hole are marked as uninitialized
Lucas De Marchi25985ed2011-03-30 22:57:33 -03002771 * to prevent parallel buffered read to expose the stale data
Mingming Cao4c0425f2009-09-28 15:48:41 -04002772 * before DIO complete the data IO.
Mingming Cao8d5d02e2009-09-28 15:48:29 -04002773 *
2774 * As to previously fallocated extents, ext4 get_block
Mingming Cao4c0425f2009-09-28 15:48:41 -04002775 * will just simply mark the buffer mapped but still
2776 * keep the extents uninitialized.
2777 *
Mingming Cao8d5d02e2009-09-28 15:48:29 -04002778 * for non AIO case, we will convert those unwritten extents
2779 * to written after return back from blockdev_direct_IO.
2780 *
2781 * for async DIO, the conversion needs to be defered when
2782 * the IO is completed. The ext4 end_io callback function
2783 * will be called to take care of the conversion work.
2784 * Here for async case, we allocate an io_end structure to
2785 * hook to the iocb.
Mingming Cao4c0425f2009-09-28 15:48:41 -04002786 */
Mingming Cao8d5d02e2009-09-28 15:48:29 -04002787 iocb->private = NULL;
2788 EXT4_I(inode)->cur_aio_dio = NULL;
2789 if (!is_sync_kiocb(iocb)) {
Jiaying Zhang744692d2010-03-04 16:14:02 -05002790 iocb->private = ext4_init_io_end(inode, GFP_NOFS);
Mingming Cao8d5d02e2009-09-28 15:48:29 -04002791 if (!iocb->private)
2792 return -ENOMEM;
2793 /*
2794 * we save the io structure for current async
Eric Sandeen79e83032010-07-27 11:56:07 -04002795 * direct IO, so that later ext4_map_blocks()
Mingming Cao8d5d02e2009-09-28 15:48:29 -04002796 * could flag the io structure whether there
2797 * is a unwritten extents needs to be converted
2798 * when IO is completed.
2799 */
2800 EXT4_I(inode)->cur_aio_dio = iocb->private;
2801 }
2802
Christoph Hellwigaacfc192011-06-24 14:29:47 -04002803 ret = __blockdev_direct_IO(rw, iocb, inode,
Mingming Cao4c0425f2009-09-28 15:48:41 -04002804 inode->i_sb->s_bdev, iov,
2805 offset, nr_segs,
Jiaying Zhangc7064ef2010-03-02 13:28:44 -05002806 ext4_get_block_write,
Christoph Hellwigaacfc192011-06-24 14:29:47 -04002807 ext4_end_io_dio,
2808 NULL,
2809 DIO_LOCKING | DIO_SKIP_HOLES);
Mingming Cao8d5d02e2009-09-28 15:48:29 -04002810 if (iocb->private)
2811 EXT4_I(inode)->cur_aio_dio = NULL;
2812 /*
2813 * The io_end structure takes a reference to the inode,
2814 * that structure needs to be destroyed and the
2815 * reference to the inode need to be dropped, when IO is
2816 * complete, even with 0 byte write, or failed.
2817 *
2818 * In the successful AIO DIO case, the io_end structure will be
2819 * desctroyed and the reference to the inode will be dropped
2820 * after the end_io call back function is called.
2821 *
2822 * In the case there is 0 byte write, or error case, since
2823 * VFS direct IO won't invoke the end_io call back function,
2824 * we need to free the end_io structure here.
2825 */
2826 if (ret != -EIOCBQUEUED && ret <= 0 && iocb->private) {
2827 ext4_free_io_end(iocb->private);
2828 iocb->private = NULL;
Theodore Ts'o19f5fb72010-01-24 14:34:07 -05002829 } else if (ret > 0 && ext4_test_inode_state(inode,
2830 EXT4_STATE_DIO_UNWRITTEN)) {
Mingming109f5562009-11-10 10:48:08 -05002831 int err;
Mingming Cao8d5d02e2009-09-28 15:48:29 -04002832 /*
2833 * for non AIO case, since the IO is already
Lucas De Marchi25985ed2011-03-30 22:57:33 -03002834 * completed, we could do the conversion right here
Mingming Cao8d5d02e2009-09-28 15:48:29 -04002835 */
Mingming109f5562009-11-10 10:48:08 -05002836 err = ext4_convert_unwritten_extents(inode,
2837 offset, ret);
2838 if (err < 0)
2839 ret = err;
Theodore Ts'o19f5fb72010-01-24 14:34:07 -05002840 ext4_clear_inode_state(inode, EXT4_STATE_DIO_UNWRITTEN);
Mingming109f5562009-11-10 10:48:08 -05002841 }
Mingming Cao4c0425f2009-09-28 15:48:41 -04002842 return ret;
2843 }
Mingming Cao8d5d02e2009-09-28 15:48:29 -04002844
2845 /* for write the the end of file case, we fall back to old way */
Mingming Cao4c0425f2009-09-28 15:48:41 -04002846 return ext4_ind_direct_IO(rw, iocb, iov, offset, nr_segs);
2847}
2848
2849static ssize_t ext4_direct_IO(int rw, struct kiocb *iocb,
2850 const struct iovec *iov, loff_t offset,
2851 unsigned long nr_segs)
2852{
2853 struct file *file = iocb->ki_filp;
2854 struct inode *inode = file->f_mapping->host;
Jiaying Zhang0562e0b2011-03-21 21:38:05 -04002855 ssize_t ret;
Mingming Cao4c0425f2009-09-28 15:48:41 -04002856
Jiaying Zhang0562e0b2011-03-21 21:38:05 -04002857 trace_ext4_direct_IO_enter(inode, offset, iov_length(iov, nr_segs), rw);
Dmitry Monakhov12e9b892010-05-16 22:00:00 -04002858 if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))
Jiaying Zhang0562e0b2011-03-21 21:38:05 -04002859 ret = ext4_ext_direct_IO(rw, iocb, iov, offset, nr_segs);
2860 else
2861 ret = ext4_ind_direct_IO(rw, iocb, iov, offset, nr_segs);
2862 trace_ext4_direct_IO_exit(inode, offset,
2863 iov_length(iov, nr_segs), rw, ret);
2864 return ret;
Mingming Cao4c0425f2009-09-28 15:48:41 -04002865}
2866
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002867/*
Mingming Cao617ba132006-10-11 01:20:53 -07002868 * Pages can be marked dirty completely asynchronously from ext4's journalling
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002869 * activity. By filemap_sync_pte(), try_to_unmap_one(), etc. We cannot do
2870 * much here because ->set_page_dirty is called under VFS locks. The page is
2871 * not necessarily locked.
2872 *
2873 * We cannot just dirty the page and leave attached buffers clean, because the
2874 * buffers' dirty state is "definitive". We cannot just set the buffers dirty
2875 * or jbddirty because all the journalling code will explode.
2876 *
2877 * So what we do is to mark the page "pending dirty" and next time writepage
2878 * is called, propagate that into the buffers appropriately.
2879 */
Mingming Cao617ba132006-10-11 01:20:53 -07002880static int ext4_journalled_set_page_dirty(struct page *page)
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002881{
2882 SetPageChecked(page);
2883 return __set_page_dirty_nobuffers(page);
2884}
2885
Mingming Cao617ba132006-10-11 01:20:53 -07002886static const struct address_space_operations ext4_ordered_aops = {
Hisashi Hifumi8ab22b92008-07-28 15:46:36 -07002887 .readpage = ext4_readpage,
2888 .readpages = ext4_readpages,
Aneesh Kumar K.V43ce1d22009-06-14 17:58:45 -04002889 .writepage = ext4_writepage,
Hisashi Hifumi8ab22b92008-07-28 15:46:36 -07002890 .write_begin = ext4_write_begin,
2891 .write_end = ext4_ordered_write_end,
2892 .bmap = ext4_bmap,
2893 .invalidatepage = ext4_invalidatepage,
2894 .releasepage = ext4_releasepage,
2895 .direct_IO = ext4_direct_IO,
2896 .migratepage = buffer_migrate_page,
2897 .is_partially_uptodate = block_is_partially_uptodate,
Andi Kleenaa261f52009-09-16 11:50:16 +02002898 .error_remove_page = generic_error_remove_page,
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002899};
2900
Mingming Cao617ba132006-10-11 01:20:53 -07002901static const struct address_space_operations ext4_writeback_aops = {
Hisashi Hifumi8ab22b92008-07-28 15:46:36 -07002902 .readpage = ext4_readpage,
2903 .readpages = ext4_readpages,
Aneesh Kumar K.V43ce1d22009-06-14 17:58:45 -04002904 .writepage = ext4_writepage,
Hisashi Hifumi8ab22b92008-07-28 15:46:36 -07002905 .write_begin = ext4_write_begin,
2906 .write_end = ext4_writeback_write_end,
2907 .bmap = ext4_bmap,
2908 .invalidatepage = ext4_invalidatepage,
2909 .releasepage = ext4_releasepage,
2910 .direct_IO = ext4_direct_IO,
2911 .migratepage = buffer_migrate_page,
2912 .is_partially_uptodate = block_is_partially_uptodate,
Andi Kleenaa261f52009-09-16 11:50:16 +02002913 .error_remove_page = generic_error_remove_page,
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002914};
2915
Mingming Cao617ba132006-10-11 01:20:53 -07002916static const struct address_space_operations ext4_journalled_aops = {
Hisashi Hifumi8ab22b92008-07-28 15:46:36 -07002917 .readpage = ext4_readpage,
2918 .readpages = ext4_readpages,
Aneesh Kumar K.V43ce1d22009-06-14 17:58:45 -04002919 .writepage = ext4_writepage,
Hisashi Hifumi8ab22b92008-07-28 15:46:36 -07002920 .write_begin = ext4_write_begin,
2921 .write_end = ext4_journalled_write_end,
2922 .set_page_dirty = ext4_journalled_set_page_dirty,
2923 .bmap = ext4_bmap,
2924 .invalidatepage = ext4_invalidatepage,
2925 .releasepage = ext4_releasepage,
2926 .is_partially_uptodate = block_is_partially_uptodate,
Andi Kleenaa261f52009-09-16 11:50:16 +02002927 .error_remove_page = generic_error_remove_page,
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002928};
2929
Alex Tomas64769242008-07-11 19:27:31 -04002930static const struct address_space_operations ext4_da_aops = {
Hisashi Hifumi8ab22b92008-07-28 15:46:36 -07002931 .readpage = ext4_readpage,
2932 .readpages = ext4_readpages,
Aneesh Kumar K.V43ce1d22009-06-14 17:58:45 -04002933 .writepage = ext4_writepage,
Hisashi Hifumi8ab22b92008-07-28 15:46:36 -07002934 .writepages = ext4_da_writepages,
Hisashi Hifumi8ab22b92008-07-28 15:46:36 -07002935 .write_begin = ext4_da_write_begin,
2936 .write_end = ext4_da_write_end,
2937 .bmap = ext4_bmap,
2938 .invalidatepage = ext4_da_invalidatepage,
2939 .releasepage = ext4_releasepage,
2940 .direct_IO = ext4_direct_IO,
2941 .migratepage = buffer_migrate_page,
2942 .is_partially_uptodate = block_is_partially_uptodate,
Andi Kleenaa261f52009-09-16 11:50:16 +02002943 .error_remove_page = generic_error_remove_page,
Alex Tomas64769242008-07-11 19:27:31 -04002944};
2945
Mingming Cao617ba132006-10-11 01:20:53 -07002946void ext4_set_aops(struct inode *inode)
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002947{
Aneesh Kumar K.Vcd1aac32008-07-11 19:27:31 -04002948 if (ext4_should_order_data(inode) &&
2949 test_opt(inode->i_sb, DELALLOC))
2950 inode->i_mapping->a_ops = &ext4_da_aops;
2951 else if (ext4_should_order_data(inode))
Mingming Cao617ba132006-10-11 01:20:53 -07002952 inode->i_mapping->a_ops = &ext4_ordered_aops;
Alex Tomas64769242008-07-11 19:27:31 -04002953 else if (ext4_should_writeback_data(inode) &&
2954 test_opt(inode->i_sb, DELALLOC))
2955 inode->i_mapping->a_ops = &ext4_da_aops;
Mingming Cao617ba132006-10-11 01:20:53 -07002956 else if (ext4_should_writeback_data(inode))
2957 inode->i_mapping->a_ops = &ext4_writeback_aops;
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002958 else
Mingming Cao617ba132006-10-11 01:20:53 -07002959 inode->i_mapping->a_ops = &ext4_journalled_aops;
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002960}
2961
2962/*
Mingming Cao617ba132006-10-11 01:20:53 -07002963 * ext4_block_truncate_page() zeroes out a mapping from file offset `from'
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002964 * up to the end of the block which corresponds to `from'.
2965 * This required during truncate. We need to physically zero the tail end
2966 * of that block so it doesn't yield old data if the file is later grown.
2967 */
Jan Karacf108bc2008-07-11 19:27:31 -04002968int ext4_block_truncate_page(handle_t *handle,
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002969 struct address_space *mapping, loff_t from)
2970{
Allison Henderson30848852011-05-25 07:41:32 -04002971 unsigned offset = from & (PAGE_CACHE_SIZE-1);
2972 unsigned length;
2973 unsigned blocksize;
2974 struct inode *inode = mapping->host;
2975
2976 blocksize = inode->i_sb->s_blocksize;
2977 length = blocksize - (offset & (blocksize - 1));
2978
2979 return ext4_block_zero_page_range(handle, mapping, from, length);
2980}
2981
2982/*
2983 * ext4_block_zero_page_range() zeros out a mapping of length 'length'
2984 * starting from file offset 'from'. The range to be zero'd must
2985 * be contained with in one block. If the specified range exceeds
2986 * the end of the block it will be shortened to end of the block
2987 * that cooresponds to 'from'
2988 */
2989int ext4_block_zero_page_range(handle_t *handle,
2990 struct address_space *mapping, loff_t from, loff_t length)
2991{
Mingming Cao617ba132006-10-11 01:20:53 -07002992 ext4_fsblk_t index = from >> PAGE_CACHE_SHIFT;
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002993 unsigned offset = from & (PAGE_CACHE_SIZE-1);
Allison Henderson30848852011-05-25 07:41:32 -04002994 unsigned blocksize, max, pos;
Aneesh Kumar K.V725d26d2008-01-28 23:58:27 -05002995 ext4_lblk_t iblock;
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002996 struct inode *inode = mapping->host;
2997 struct buffer_head *bh;
Jan Karacf108bc2008-07-11 19:27:31 -04002998 struct page *page;
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002999 int err = 0;
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003000
Theodore Ts'of4a01012009-07-05 22:08:16 -04003001 page = find_or_create_page(mapping, from >> PAGE_CACHE_SHIFT,
3002 mapping_gfp_mask(mapping) & ~__GFP_FS);
Jan Karacf108bc2008-07-11 19:27:31 -04003003 if (!page)
3004 return -EINVAL;
3005
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003006 blocksize = inode->i_sb->s_blocksize;
Allison Henderson30848852011-05-25 07:41:32 -04003007 max = blocksize - (offset & (blocksize - 1));
3008
3009 /*
3010 * correct length if it does not fall between
3011 * 'from' and the end of the block
3012 */
3013 if (length > max || length < 0)
3014 length = max;
3015
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003016 iblock = index << (PAGE_CACHE_SHIFT - inode->i_sb->s_blocksize_bits);
3017
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003018 if (!page_has_buffers(page))
3019 create_empty_buffers(page, blocksize, 0);
3020
3021 /* Find the buffer that contains "offset" */
3022 bh = page_buffers(page);
3023 pos = blocksize;
3024 while (offset >= pos) {
3025 bh = bh->b_this_page;
3026 iblock++;
3027 pos += blocksize;
3028 }
3029
3030 err = 0;
3031 if (buffer_freed(bh)) {
3032 BUFFER_TRACE(bh, "freed: skip");
3033 goto unlock;
3034 }
3035
3036 if (!buffer_mapped(bh)) {
3037 BUFFER_TRACE(bh, "unmapped");
Mingming Cao617ba132006-10-11 01:20:53 -07003038 ext4_get_block(inode, iblock, bh, 0);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003039 /* unmapped? It's a hole - nothing to do */
3040 if (!buffer_mapped(bh)) {
3041 BUFFER_TRACE(bh, "still unmapped");
3042 goto unlock;
3043 }
3044 }
3045
3046 /* Ok, it's mapped. Make sure it's up-to-date */
3047 if (PageUptodate(page))
3048 set_buffer_uptodate(bh);
3049
3050 if (!buffer_uptodate(bh)) {
3051 err = -EIO;
3052 ll_rw_block(READ, 1, &bh);
3053 wait_on_buffer(bh);
3054 /* Uhhuh. Read error. Complain and punt. */
3055 if (!buffer_uptodate(bh))
3056 goto unlock;
3057 }
3058
Mingming Cao617ba132006-10-11 01:20:53 -07003059 if (ext4_should_journal_data(inode)) {
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003060 BUFFER_TRACE(bh, "get write access");
Mingming Cao617ba132006-10-11 01:20:53 -07003061 err = ext4_journal_get_write_access(handle, bh);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003062 if (err)
3063 goto unlock;
3064 }
3065
Christoph Lametereebd2aa2008-02-04 22:28:29 -08003066 zero_user(page, offset, length);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003067
3068 BUFFER_TRACE(bh, "zeroed end of block");
3069
3070 err = 0;
Mingming Cao617ba132006-10-11 01:20:53 -07003071 if (ext4_should_journal_data(inode)) {
Frank Mayhar03901312009-01-07 00:06:22 -05003072 err = ext4_handle_dirty_metadata(handle, inode, bh);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003073 } else {
Theodore Ts'o8aefcd52011-01-10 12:29:43 -05003074 if (ext4_should_order_data(inode) && EXT4_I(inode)->jinode)
Jan Kara678aaf42008-07-11 19:27:31 -04003075 err = ext4_jbd2_file_inode(handle, inode);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003076 mark_buffer_dirty(bh);
3077 }
3078
3079unlock:
3080 unlock_page(page);
3081 page_cache_release(page);
3082 return err;
3083}
3084
Duane Griffin91ef4ca2008-07-11 19:27:31 -04003085int ext4_can_truncate(struct inode *inode)
3086{
Duane Griffin91ef4ca2008-07-11 19:27:31 -04003087 if (S_ISREG(inode->i_mode))
3088 return 1;
3089 if (S_ISDIR(inode->i_mode))
3090 return 1;
3091 if (S_ISLNK(inode->i_mode))
3092 return !ext4_inode_is_fast_symlink(inode);
3093 return 0;
3094}
3095
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003096/*
Allison Hendersona4bb6b62011-05-25 07:41:50 -04003097 * ext4_punch_hole: punches a hole in a file by releaseing the blocks
3098 * associated with the given offset and length
3099 *
3100 * @inode: File inode
3101 * @offset: The offset where the hole will begin
3102 * @len: The length of the hole
3103 *
3104 * Returns: 0 on sucess or negative on failure
3105 */
3106
3107int ext4_punch_hole(struct file *file, loff_t offset, loff_t length)
3108{
3109 struct inode *inode = file->f_path.dentry->d_inode;
3110 if (!S_ISREG(inode->i_mode))
3111 return -ENOTSUPP;
3112
3113 if (!ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)) {
3114 /* TODO: Add support for non extent hole punching */
3115 return -ENOTSUPP;
3116 }
3117
3118 return ext4_ext_punch_hole(file, offset, length);
3119}
3120
3121/*
Mingming Cao617ba132006-10-11 01:20:53 -07003122 * ext4_truncate()
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003123 *
Mingming Cao617ba132006-10-11 01:20:53 -07003124 * We block out ext4_get_block() block instantiations across the entire
3125 * transaction, and VFS/VM ensures that ext4_truncate() cannot run
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003126 * simultaneously on behalf of the same inode.
3127 *
3128 * As we work through the truncate and commmit bits of it to the journal there
3129 * is one core, guiding principle: the file's tree must always be consistent on
3130 * disk. We must be able to restart the truncate after a crash.
3131 *
3132 * The file's tree may be transiently inconsistent in memory (although it
3133 * probably isn't), but whenever we close off and commit a journal transaction,
3134 * the contents of (the filesystem + the journal) must be consistent and
3135 * restartable. It's pretty simple, really: bottom up, right to left (although
3136 * left-to-right works OK too).
3137 *
3138 * Note that at recovery time, journal replay occurs *before* the restart of
3139 * truncate against the orphan inode list.
3140 *
3141 * The committed inode has the new, desired i_size (which is the same as
Mingming Cao617ba132006-10-11 01:20:53 -07003142 * i_disksize in this case). After a crash, ext4_orphan_cleanup() will see
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003143 * that this inode's truncate did not complete and it will again call
Mingming Cao617ba132006-10-11 01:20:53 -07003144 * ext4_truncate() to have another go. So there will be instantiated blocks
3145 * to the right of the truncation point in a crashed ext4 filesystem. But
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003146 * that's fine - as long as they are linked from the inode, the post-crash
Mingming Cao617ba132006-10-11 01:20:53 -07003147 * ext4_truncate() run will find them and release them.
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003148 */
Mingming Cao617ba132006-10-11 01:20:53 -07003149void ext4_truncate(struct inode *inode)
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003150{
Jiaying Zhang0562e0b2011-03-21 21:38:05 -04003151 trace_ext4_truncate_enter(inode);
3152
Duane Griffin91ef4ca2008-07-11 19:27:31 -04003153 if (!ext4_can_truncate(inode))
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003154 return;
3155
Dmitry Monakhov12e9b892010-05-16 22:00:00 -04003156 ext4_clear_inode_flag(inode, EXT4_INODE_EOFBLOCKS);
Jiaying Zhangc8d46e42010-02-24 09:52:53 -05003157
Theodore Ts'o5534fb52009-09-17 09:34:16 -04003158 if (inode->i_size == 0 && !test_opt(inode->i_sb, NO_AUTO_DA_ALLOC))
Theodore Ts'o19f5fb72010-01-24 14:34:07 -05003159 ext4_set_inode_state(inode, EXT4_STATE_DA_ALLOC_CLOSE);
Theodore Ts'o7d8f9f72009-02-24 08:21:14 -05003160
Amir Goldsteinff9893d2011-06-27 16:36:31 -04003161 if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))
Jan Karacf108bc2008-07-11 19:27:31 -04003162 ext4_ext_truncate(inode);
Amir Goldsteinff9893d2011-06-27 16:36:31 -04003163 else
3164 ext4_ind_truncate(inode);
Alex Tomasa86c6182006-10-11 01:21:03 -07003165
Jiaying Zhang0562e0b2011-03-21 21:38:05 -04003166 trace_ext4_truncate_exit(inode);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003167}
3168
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003169/*
Mingming Cao617ba132006-10-11 01:20:53 -07003170 * ext4_get_inode_loc returns with an extra refcount against the inode's
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003171 * underlying buffer_head on success. If 'in_mem' is true, we have all
3172 * data in memory that is needed to recreate the on-disk version of this
3173 * inode.
3174 */
Mingming Cao617ba132006-10-11 01:20:53 -07003175static int __ext4_get_inode_loc(struct inode *inode,
3176 struct ext4_iloc *iloc, int in_mem)
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003177{
Theodore Ts'o240799c2008-10-09 23:53:47 -04003178 struct ext4_group_desc *gdp;
3179 struct buffer_head *bh;
3180 struct super_block *sb = inode->i_sb;
3181 ext4_fsblk_t block;
3182 int inodes_per_block, inode_offset;
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003183
Aneesh Kumar K.V3a06d772008-11-22 15:04:59 -05003184 iloc->bh = NULL;
Theodore Ts'o240799c2008-10-09 23:53:47 -04003185 if (!ext4_valid_inum(sb, inode->i_ino))
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003186 return -EIO;
3187
Theodore Ts'o240799c2008-10-09 23:53:47 -04003188 iloc->block_group = (inode->i_ino - 1) / EXT4_INODES_PER_GROUP(sb);
3189 gdp = ext4_get_group_desc(sb, iloc->block_group, NULL);
3190 if (!gdp)
3191 return -EIO;
3192
3193 /*
3194 * Figure out the offset within the block group inode table
3195 */
Tao Ma00d09882011-05-09 10:26:41 -04003196 inodes_per_block = EXT4_SB(sb)->s_inodes_per_block;
Theodore Ts'o240799c2008-10-09 23:53:47 -04003197 inode_offset = ((inode->i_ino - 1) %
3198 EXT4_INODES_PER_GROUP(sb));
3199 block = ext4_inode_table(sb, gdp) + (inode_offset / inodes_per_block);
3200 iloc->offset = (inode_offset % inodes_per_block) * EXT4_INODE_SIZE(sb);
3201
3202 bh = sb_getblk(sb, block);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003203 if (!bh) {
Theodore Ts'oc398eda2010-07-27 11:56:40 -04003204 EXT4_ERROR_INODE_BLOCK(inode, block,
3205 "unable to read itable block");
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003206 return -EIO;
3207 }
3208 if (!buffer_uptodate(bh)) {
3209 lock_buffer(bh);
Hidehiro Kawai9c83a922008-07-26 16:39:26 -04003210
3211 /*
3212 * If the buffer has the write error flag, we have failed
3213 * to write out another inode in the same block. In this
3214 * case, we don't have to read the block because we may
3215 * read the old inode data successfully.
3216 */
3217 if (buffer_write_io_error(bh) && !buffer_uptodate(bh))
3218 set_buffer_uptodate(bh);
3219
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003220 if (buffer_uptodate(bh)) {
3221 /* someone brought it uptodate while we waited */
3222 unlock_buffer(bh);
3223 goto has_buffer;
3224 }
3225
3226 /*
3227 * If we have all information of the inode in memory and this
3228 * is the only valid inode in the block, we need not read the
3229 * block.
3230 */
3231 if (in_mem) {
3232 struct buffer_head *bitmap_bh;
Theodore Ts'o240799c2008-10-09 23:53:47 -04003233 int i, start;
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003234
Theodore Ts'o240799c2008-10-09 23:53:47 -04003235 start = inode_offset & ~(inodes_per_block - 1);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003236
3237 /* Is the inode bitmap in cache? */
Theodore Ts'o240799c2008-10-09 23:53:47 -04003238 bitmap_bh = sb_getblk(sb, ext4_inode_bitmap(sb, gdp));
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003239 if (!bitmap_bh)
3240 goto make_io;
3241
3242 /*
3243 * If the inode bitmap isn't in cache then the
3244 * optimisation may end up performing two reads instead
3245 * of one, so skip it.
3246 */
3247 if (!buffer_uptodate(bitmap_bh)) {
3248 brelse(bitmap_bh);
3249 goto make_io;
3250 }
Theodore Ts'o240799c2008-10-09 23:53:47 -04003251 for (i = start; i < start + inodes_per_block; i++) {
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003252 if (i == inode_offset)
3253 continue;
Mingming Cao617ba132006-10-11 01:20:53 -07003254 if (ext4_test_bit(i, bitmap_bh->b_data))
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003255 break;
3256 }
3257 brelse(bitmap_bh);
Theodore Ts'o240799c2008-10-09 23:53:47 -04003258 if (i == start + inodes_per_block) {
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003259 /* all other inodes are free, so skip I/O */
3260 memset(bh->b_data, 0, bh->b_size);
3261 set_buffer_uptodate(bh);
3262 unlock_buffer(bh);
3263 goto has_buffer;
3264 }
3265 }
3266
3267make_io:
3268 /*
Theodore Ts'o240799c2008-10-09 23:53:47 -04003269 * If we need to do any I/O, try to pre-readahead extra
3270 * blocks from the inode table.
3271 */
3272 if (EXT4_SB(sb)->s_inode_readahead_blks) {
3273 ext4_fsblk_t b, end, table;
3274 unsigned num;
3275
3276 table = ext4_inode_table(sb, gdp);
Theodore Ts'ob713a5e2009-03-31 09:11:14 -04003277 /* s_inode_readahead_blks is always a power of 2 */
Theodore Ts'o240799c2008-10-09 23:53:47 -04003278 b = block & ~(EXT4_SB(sb)->s_inode_readahead_blks-1);
3279 if (table > b)
3280 b = table;
3281 end = b + EXT4_SB(sb)->s_inode_readahead_blks;
3282 num = EXT4_INODES_PER_GROUP(sb);
3283 if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
3284 EXT4_FEATURE_RO_COMPAT_GDT_CSUM))
Aneesh Kumar K.V560671a2009-01-05 22:20:24 -05003285 num -= ext4_itable_unused_count(sb, gdp);
Theodore Ts'o240799c2008-10-09 23:53:47 -04003286 table += num / inodes_per_block;
3287 if (end > table)
3288 end = table;
3289 while (b <= end)
3290 sb_breadahead(sb, b++);
3291 }
3292
3293 /*
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003294 * There are other valid inodes in the buffer, this inode
3295 * has in-inode xattrs, or we don't have this inode in memory.
3296 * Read the block from disk.
3297 */
Jiaying Zhang0562e0b2011-03-21 21:38:05 -04003298 trace_ext4_load_inode(inode);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003299 get_bh(bh);
3300 bh->b_end_io = end_buffer_read_sync;
Christoph Hellwig65299a32011-08-23 14:50:29 +02003301 submit_bh(READ | REQ_META | REQ_PRIO, bh);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003302 wait_on_buffer(bh);
3303 if (!buffer_uptodate(bh)) {
Theodore Ts'oc398eda2010-07-27 11:56:40 -04003304 EXT4_ERROR_INODE_BLOCK(inode, block,
3305 "unable to read itable block");
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003306 brelse(bh);
3307 return -EIO;
3308 }
3309 }
3310has_buffer:
3311 iloc->bh = bh;
3312 return 0;
3313}
3314
Mingming Cao617ba132006-10-11 01:20:53 -07003315int ext4_get_inode_loc(struct inode *inode, struct ext4_iloc *iloc)
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003316{
3317 /* We have all inode data except xattrs in memory here. */
Mingming Cao617ba132006-10-11 01:20:53 -07003318 return __ext4_get_inode_loc(inode, iloc,
Theodore Ts'o19f5fb72010-01-24 14:34:07 -05003319 !ext4_test_inode_state(inode, EXT4_STATE_XATTR));
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003320}
3321
Mingming Cao617ba132006-10-11 01:20:53 -07003322void ext4_set_inode_flags(struct inode *inode)
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003323{
Mingming Cao617ba132006-10-11 01:20:53 -07003324 unsigned int flags = EXT4_I(inode)->i_flags;
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003325
3326 inode->i_flags &= ~(S_SYNC|S_APPEND|S_IMMUTABLE|S_NOATIME|S_DIRSYNC);
Mingming Cao617ba132006-10-11 01:20:53 -07003327 if (flags & EXT4_SYNC_FL)
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003328 inode->i_flags |= S_SYNC;
Mingming Cao617ba132006-10-11 01:20:53 -07003329 if (flags & EXT4_APPEND_FL)
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003330 inode->i_flags |= S_APPEND;
Mingming Cao617ba132006-10-11 01:20:53 -07003331 if (flags & EXT4_IMMUTABLE_FL)
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003332 inode->i_flags |= S_IMMUTABLE;
Mingming Cao617ba132006-10-11 01:20:53 -07003333 if (flags & EXT4_NOATIME_FL)
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003334 inode->i_flags |= S_NOATIME;
Mingming Cao617ba132006-10-11 01:20:53 -07003335 if (flags & EXT4_DIRSYNC_FL)
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003336 inode->i_flags |= S_DIRSYNC;
3337}
3338
Jan Karaff9ddf72007-07-18 09:24:20 -04003339/* Propagate flags from i_flags to EXT4_I(inode)->i_flags */
3340void ext4_get_inode_flags(struct ext4_inode_info *ei)
3341{
Dmitry Monakhov84a8dce2010-06-05 11:51:27 -04003342 unsigned int vfs_fl;
3343 unsigned long old_fl, new_fl;
Jan Karaff9ddf72007-07-18 09:24:20 -04003344
Dmitry Monakhov84a8dce2010-06-05 11:51:27 -04003345 do {
3346 vfs_fl = ei->vfs_inode.i_flags;
3347 old_fl = ei->i_flags;
3348 new_fl = old_fl & ~(EXT4_SYNC_FL|EXT4_APPEND_FL|
3349 EXT4_IMMUTABLE_FL|EXT4_NOATIME_FL|
3350 EXT4_DIRSYNC_FL);
3351 if (vfs_fl & S_SYNC)
3352 new_fl |= EXT4_SYNC_FL;
3353 if (vfs_fl & S_APPEND)
3354 new_fl |= EXT4_APPEND_FL;
3355 if (vfs_fl & S_IMMUTABLE)
3356 new_fl |= EXT4_IMMUTABLE_FL;
3357 if (vfs_fl & S_NOATIME)
3358 new_fl |= EXT4_NOATIME_FL;
3359 if (vfs_fl & S_DIRSYNC)
3360 new_fl |= EXT4_DIRSYNC_FL;
3361 } while (cmpxchg(&ei->i_flags, old_fl, new_fl) != old_fl);
Jan Karaff9ddf72007-07-18 09:24:20 -04003362}
Theodore Ts'ode9a55b2009-06-14 17:45:34 -04003363
Aneesh Kumar K.V0fc1b452008-01-28 23:58:26 -05003364static blkcnt_t ext4_inode_blocks(struct ext4_inode *raw_inode,
Theodore Ts'ode9a55b2009-06-14 17:45:34 -04003365 struct ext4_inode_info *ei)
Aneesh Kumar K.V0fc1b452008-01-28 23:58:26 -05003366{
3367 blkcnt_t i_blocks ;
Aneesh Kumar K.V8180a562008-01-28 23:58:27 -05003368 struct inode *inode = &(ei->vfs_inode);
3369 struct super_block *sb = inode->i_sb;
Aneesh Kumar K.V0fc1b452008-01-28 23:58:26 -05003370
3371 if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
3372 EXT4_FEATURE_RO_COMPAT_HUGE_FILE)) {
3373 /* we are using combined 48 bit field */
3374 i_blocks = ((u64)le16_to_cpu(raw_inode->i_blocks_high)) << 32 |
3375 le32_to_cpu(raw_inode->i_blocks_lo);
Theodore Ts'o07a03822010-06-14 09:54:48 -04003376 if (ext4_test_inode_flag(inode, EXT4_INODE_HUGE_FILE)) {
Aneesh Kumar K.V8180a562008-01-28 23:58:27 -05003377 /* i_blocks represent file system block size */
3378 return i_blocks << (inode->i_blkbits - 9);
3379 } else {
3380 return i_blocks;
3381 }
Aneesh Kumar K.V0fc1b452008-01-28 23:58:26 -05003382 } else {
3383 return le32_to_cpu(raw_inode->i_blocks_lo);
3384 }
3385}
Jan Karaff9ddf72007-07-18 09:24:20 -04003386
David Howells1d1fe1e2008-02-07 00:15:37 -08003387struct inode *ext4_iget(struct super_block *sb, unsigned long ino)
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003388{
Mingming Cao617ba132006-10-11 01:20:53 -07003389 struct ext4_iloc iloc;
3390 struct ext4_inode *raw_inode;
David Howells1d1fe1e2008-02-07 00:15:37 -08003391 struct ext4_inode_info *ei;
David Howells1d1fe1e2008-02-07 00:15:37 -08003392 struct inode *inode;
Jan Karab436b9b2009-12-08 23:51:10 -05003393 journal_t *journal = EXT4_SB(sb)->s_journal;
David Howells1d1fe1e2008-02-07 00:15:37 -08003394 long ret;
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003395 int block;
3396
David Howells1d1fe1e2008-02-07 00:15:37 -08003397 inode = iget_locked(sb, ino);
3398 if (!inode)
3399 return ERR_PTR(-ENOMEM);
3400 if (!(inode->i_state & I_NEW))
3401 return inode;
3402
3403 ei = EXT4_I(inode);
Peter Huewe7dc57612011-02-21 21:01:42 -05003404 iloc.bh = NULL;
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003405
David Howells1d1fe1e2008-02-07 00:15:37 -08003406 ret = __ext4_get_inode_loc(inode, &iloc, 0);
3407 if (ret < 0)
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003408 goto bad_inode;
Mingming Cao617ba132006-10-11 01:20:53 -07003409 raw_inode = ext4_raw_inode(&iloc);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003410 inode->i_mode = le16_to_cpu(raw_inode->i_mode);
3411 inode->i_uid = (uid_t)le16_to_cpu(raw_inode->i_uid_low);
3412 inode->i_gid = (gid_t)le16_to_cpu(raw_inode->i_gid_low);
Theodore Ts'oaf5bc922008-09-08 22:25:24 -04003413 if (!(test_opt(inode->i_sb, NO_UID32))) {
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003414 inode->i_uid |= le16_to_cpu(raw_inode->i_uid_high) << 16;
3415 inode->i_gid |= le16_to_cpu(raw_inode->i_gid_high) << 16;
3416 }
3417 inode->i_nlink = le16_to_cpu(raw_inode->i_links_count);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003418
Theodore Ts'o353eb832011-01-10 12:18:25 -05003419 ext4_clear_state_flags(ei); /* Only relevant on 32-bit archs */
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003420 ei->i_dir_start_lookup = 0;
3421 ei->i_dtime = le32_to_cpu(raw_inode->i_dtime);
3422 /* We now have enough fields to check if the inode was active or not.
3423 * This is needed because nfsd might try to access dead inodes
3424 * the test is that same one that e2fsck uses
3425 * NeilBrown 1999oct15
3426 */
3427 if (inode->i_nlink == 0) {
3428 if (inode->i_mode == 0 ||
Mingming Cao617ba132006-10-11 01:20:53 -07003429 !(EXT4_SB(inode->i_sb)->s_mount_state & EXT4_ORPHAN_FS)) {
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003430 /* this inode is deleted */
David Howells1d1fe1e2008-02-07 00:15:37 -08003431 ret = -ESTALE;
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003432 goto bad_inode;
3433 }
3434 /* The only unlinked inodes we let through here have
3435 * valid i_mode and are being read by the orphan
3436 * recovery code: that's fine, we're about to complete
3437 * the process of deleting those. */
3438 }
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003439 ei->i_flags = le32_to_cpu(raw_inode->i_flags);
Aneesh Kumar K.V0fc1b452008-01-28 23:58:26 -05003440 inode->i_blocks = ext4_inode_blocks(raw_inode, ei);
Aneesh Kumar K.V7973c0c2008-01-28 23:58:27 -05003441 ei->i_file_acl = le32_to_cpu(raw_inode->i_file_acl_lo);
Theodore Ts'oa9e81742009-04-24 16:11:18 -04003442 if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_64BIT))
Badari Pulavartya1ddeb72006-10-11 01:21:09 -07003443 ei->i_file_acl |=
3444 ((__u64)le16_to_cpu(raw_inode->i_file_acl_high)) << 32;
Aneesh Kumar K.Va48380f2008-01-28 23:58:27 -05003445 inode->i_size = ext4_isize(raw_inode);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003446 ei->i_disksize = inode->i_size;
Dmitry Monakhova9e7f442009-12-14 15:21:14 +03003447#ifdef CONFIG_QUOTA
3448 ei->i_reserved_quota = 0;
3449#endif
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003450 inode->i_generation = le32_to_cpu(raw_inode->i_generation);
3451 ei->i_block_group = iloc.block_group;
Theodore Ts'oa4912122009-03-12 12:18:34 -04003452 ei->i_last_alloc_group = ~0;
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003453 /*
3454 * NOTE! The in-memory inode i_data array is in little-endian order
3455 * even on big-endian machines: we do NOT byteswap the block numbers!
3456 */
Mingming Cao617ba132006-10-11 01:20:53 -07003457 for (block = 0; block < EXT4_N_BLOCKS; block++)
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003458 ei->i_data[block] = raw_inode->i_block[block];
3459 INIT_LIST_HEAD(&ei->i_orphan);
3460
Jan Karab436b9b2009-12-08 23:51:10 -05003461 /*
3462 * Set transaction id's of transactions that have to be committed
3463 * to finish f[data]sync. We set them to currently running transaction
3464 * as we cannot be sure that the inode or some of its metadata isn't
3465 * part of the transaction - the inode could have been reclaimed and
3466 * now it is reread from disk.
3467 */
3468 if (journal) {
3469 transaction_t *transaction;
3470 tid_t tid;
3471
Theodore Ts'oa931da62010-08-03 21:35:12 -04003472 read_lock(&journal->j_state_lock);
Jan Karab436b9b2009-12-08 23:51:10 -05003473 if (journal->j_running_transaction)
3474 transaction = journal->j_running_transaction;
3475 else
3476 transaction = journal->j_committing_transaction;
3477 if (transaction)
3478 tid = transaction->t_tid;
3479 else
3480 tid = journal->j_commit_sequence;
Theodore Ts'oa931da62010-08-03 21:35:12 -04003481 read_unlock(&journal->j_state_lock);
Jan Karab436b9b2009-12-08 23:51:10 -05003482 ei->i_sync_tid = tid;
3483 ei->i_datasync_tid = tid;
3484 }
3485
Eric Sandeen0040d982008-02-05 22:36:43 -05003486 if (EXT4_INODE_SIZE(inode->i_sb) > EXT4_GOOD_OLD_INODE_SIZE) {
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003487 ei->i_extra_isize = le16_to_cpu(raw_inode->i_extra_isize);
Mingming Cao617ba132006-10-11 01:20:53 -07003488 if (EXT4_GOOD_OLD_INODE_SIZE + ei->i_extra_isize >
Kirill Korotaeve5d28612007-06-23 17:16:51 -07003489 EXT4_INODE_SIZE(inode->i_sb)) {
David Howells1d1fe1e2008-02-07 00:15:37 -08003490 ret = -EIO;
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003491 goto bad_inode;
Kirill Korotaeve5d28612007-06-23 17:16:51 -07003492 }
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003493 if (ei->i_extra_isize == 0) {
3494 /* The extra space is currently unused. Use it. */
Mingming Cao617ba132006-10-11 01:20:53 -07003495 ei->i_extra_isize = sizeof(struct ext4_inode) -
3496 EXT4_GOOD_OLD_INODE_SIZE;
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003497 } else {
3498 __le32 *magic = (void *)raw_inode +
Mingming Cao617ba132006-10-11 01:20:53 -07003499 EXT4_GOOD_OLD_INODE_SIZE +
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003500 ei->i_extra_isize;
Mingming Cao617ba132006-10-11 01:20:53 -07003501 if (*magic == cpu_to_le32(EXT4_XATTR_MAGIC))
Theodore Ts'o19f5fb72010-01-24 14:34:07 -05003502 ext4_set_inode_state(inode, EXT4_STATE_XATTR);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003503 }
3504 } else
3505 ei->i_extra_isize = 0;
3506
Kalpak Shahef7f3832007-07-18 09:15:20 -04003507 EXT4_INODE_GET_XTIME(i_ctime, inode, raw_inode);
3508 EXT4_INODE_GET_XTIME(i_mtime, inode, raw_inode);
3509 EXT4_INODE_GET_XTIME(i_atime, inode, raw_inode);
3510 EXT4_EINODE_GET_XTIME(i_crtime, ei, raw_inode);
3511
Jean Noel Cordenner25ec56b2008-01-28 23:58:27 -05003512 inode->i_version = le32_to_cpu(raw_inode->i_disk_version);
3513 if (EXT4_INODE_SIZE(inode->i_sb) > EXT4_GOOD_OLD_INODE_SIZE) {
3514 if (EXT4_FITS_IN_INODE(raw_inode, ei, i_version_hi))
3515 inode->i_version |=
3516 (__u64)(le32_to_cpu(raw_inode->i_version_hi)) << 32;
3517 }
3518
Theodore Ts'oc4b5a612009-04-24 18:45:35 -04003519 ret = 0;
Theodore Ts'o485c26e2009-04-24 13:43:20 -04003520 if (ei->i_file_acl &&
Theodore Ts'o10329882009-11-15 15:29:56 -05003521 !ext4_data_block_valid(EXT4_SB(sb), ei->i_file_acl, 1)) {
Theodore Ts'o24676da2010-05-16 21:00:00 -04003522 EXT4_ERROR_INODE(inode, "bad extended attribute block %llu",
3523 ei->i_file_acl);
Theodore Ts'o485c26e2009-04-24 13:43:20 -04003524 ret = -EIO;
3525 goto bad_inode;
Theodore Ts'o07a03822010-06-14 09:54:48 -04003526 } else if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)) {
Theodore Ts'oc4b5a612009-04-24 18:45:35 -04003527 if (S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) ||
3528 (S_ISLNK(inode->i_mode) &&
3529 !ext4_inode_is_fast_symlink(inode)))
3530 /* Validate extent which is part of inode */
3531 ret = ext4_ext_check_inode(inode);
Theodore Ts'ode9a55b2009-06-14 17:45:34 -04003532 } else if (S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) ||
Thiemo Nagelfe2c8192009-03-31 08:36:10 -04003533 (S_ISLNK(inode->i_mode) &&
3534 !ext4_inode_is_fast_symlink(inode))) {
Theodore Ts'ode9a55b2009-06-14 17:45:34 -04003535 /* Validate block references which are part of inode */
Theodore Ts'o1f7d1e72011-06-27 19:16:02 -04003536 ret = ext4_ind_check_inode(inode);
Thiemo Nagelfe2c8192009-03-31 08:36:10 -04003537 }
Theodore Ts'o567f3e92009-11-14 08:19:05 -05003538 if (ret)
Theodore Ts'ode9a55b2009-06-14 17:45:34 -04003539 goto bad_inode;
Aneesh Kumar K.V7a262f72009-03-27 16:39:58 -04003540
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003541 if (S_ISREG(inode->i_mode)) {
Mingming Cao617ba132006-10-11 01:20:53 -07003542 inode->i_op = &ext4_file_inode_operations;
3543 inode->i_fop = &ext4_file_operations;
3544 ext4_set_aops(inode);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003545 } else if (S_ISDIR(inode->i_mode)) {
Mingming Cao617ba132006-10-11 01:20:53 -07003546 inode->i_op = &ext4_dir_inode_operations;
3547 inode->i_fop = &ext4_dir_operations;
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003548 } else if (S_ISLNK(inode->i_mode)) {
Duane Griffine83c1392008-12-19 20:47:15 +00003549 if (ext4_inode_is_fast_symlink(inode)) {
Mingming Cao617ba132006-10-11 01:20:53 -07003550 inode->i_op = &ext4_fast_symlink_inode_operations;
Duane Griffine83c1392008-12-19 20:47:15 +00003551 nd_terminate_link(ei->i_data, inode->i_size,
3552 sizeof(ei->i_data) - 1);
3553 } else {
Mingming Cao617ba132006-10-11 01:20:53 -07003554 inode->i_op = &ext4_symlink_inode_operations;
3555 ext4_set_aops(inode);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003556 }
Theodore Ts'o563bdd62009-03-26 00:06:19 -04003557 } else if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode) ||
3558 S_ISFIFO(inode->i_mode) || S_ISSOCK(inode->i_mode)) {
Mingming Cao617ba132006-10-11 01:20:53 -07003559 inode->i_op = &ext4_special_inode_operations;
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003560 if (raw_inode->i_block[0])
3561 init_special_inode(inode, inode->i_mode,
3562 old_decode_dev(le32_to_cpu(raw_inode->i_block[0])));
3563 else
3564 init_special_inode(inode, inode->i_mode,
3565 new_decode_dev(le32_to_cpu(raw_inode->i_block[1])));
Theodore Ts'o563bdd62009-03-26 00:06:19 -04003566 } else {
Theodore Ts'o563bdd62009-03-26 00:06:19 -04003567 ret = -EIO;
Theodore Ts'o24676da2010-05-16 21:00:00 -04003568 EXT4_ERROR_INODE(inode, "bogus i_mode (%o)", inode->i_mode);
Theodore Ts'o563bdd62009-03-26 00:06:19 -04003569 goto bad_inode;
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003570 }
Theodore Ts'oaf5bc922008-09-08 22:25:24 -04003571 brelse(iloc.bh);
Mingming Cao617ba132006-10-11 01:20:53 -07003572 ext4_set_inode_flags(inode);
David Howells1d1fe1e2008-02-07 00:15:37 -08003573 unlock_new_inode(inode);
3574 return inode;
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003575
3576bad_inode:
Theodore Ts'o567f3e92009-11-14 08:19:05 -05003577 brelse(iloc.bh);
David Howells1d1fe1e2008-02-07 00:15:37 -08003578 iget_failed(inode);
3579 return ERR_PTR(ret);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003580}
3581
Aneesh Kumar K.V0fc1b452008-01-28 23:58:26 -05003582static int ext4_inode_blocks_set(handle_t *handle,
3583 struct ext4_inode *raw_inode,
3584 struct ext4_inode_info *ei)
3585{
3586 struct inode *inode = &(ei->vfs_inode);
3587 u64 i_blocks = inode->i_blocks;
3588 struct super_block *sb = inode->i_sb;
Aneesh Kumar K.V0fc1b452008-01-28 23:58:26 -05003589
3590 if (i_blocks <= ~0U) {
3591 /*
3592 * i_blocks can be represnted in a 32 bit variable
3593 * as multiple of 512 bytes
3594 */
Aneesh Kumar K.V8180a562008-01-28 23:58:27 -05003595 raw_inode->i_blocks_lo = cpu_to_le32(i_blocks);
Aneesh Kumar K.V0fc1b452008-01-28 23:58:26 -05003596 raw_inode->i_blocks_high = 0;
Dmitry Monakhov84a8dce2010-06-05 11:51:27 -04003597 ext4_clear_inode_flag(inode, EXT4_INODE_HUGE_FILE);
Theodore Ts'of287a1a2008-10-16 22:50:48 -04003598 return 0;
3599 }
3600 if (!EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_HUGE_FILE))
3601 return -EFBIG;
3602
3603 if (i_blocks <= 0xffffffffffffULL) {
Aneesh Kumar K.V0fc1b452008-01-28 23:58:26 -05003604 /*
3605 * i_blocks can be represented in a 48 bit variable
3606 * as multiple of 512 bytes
3607 */
Aneesh Kumar K.V8180a562008-01-28 23:58:27 -05003608 raw_inode->i_blocks_lo = cpu_to_le32(i_blocks);
Aneesh Kumar K.V0fc1b452008-01-28 23:58:26 -05003609 raw_inode->i_blocks_high = cpu_to_le16(i_blocks >> 32);
Dmitry Monakhov84a8dce2010-06-05 11:51:27 -04003610 ext4_clear_inode_flag(inode, EXT4_INODE_HUGE_FILE);
Aneesh Kumar K.V0fc1b452008-01-28 23:58:26 -05003611 } else {
Dmitry Monakhov84a8dce2010-06-05 11:51:27 -04003612 ext4_set_inode_flag(inode, EXT4_INODE_HUGE_FILE);
Aneesh Kumar K.V8180a562008-01-28 23:58:27 -05003613 /* i_block is stored in file system block size */
3614 i_blocks = i_blocks >> (inode->i_blkbits - 9);
3615 raw_inode->i_blocks_lo = cpu_to_le32(i_blocks);
3616 raw_inode->i_blocks_high = cpu_to_le16(i_blocks >> 32);
Aneesh Kumar K.V0fc1b452008-01-28 23:58:26 -05003617 }
Theodore Ts'of287a1a2008-10-16 22:50:48 -04003618 return 0;
Aneesh Kumar K.V0fc1b452008-01-28 23:58:26 -05003619}
3620
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003621/*
3622 * Post the struct inode info into an on-disk inode location in the
3623 * buffer-cache. This gobbles the caller's reference to the
3624 * buffer_head in the inode location struct.
3625 *
3626 * The caller must have write access to iloc->bh.
3627 */
Mingming Cao617ba132006-10-11 01:20:53 -07003628static int ext4_do_update_inode(handle_t *handle,
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003629 struct inode *inode,
Frank Mayhar830156c2009-09-29 10:07:47 -04003630 struct ext4_iloc *iloc)
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003631{
Mingming Cao617ba132006-10-11 01:20:53 -07003632 struct ext4_inode *raw_inode = ext4_raw_inode(iloc);
3633 struct ext4_inode_info *ei = EXT4_I(inode);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003634 struct buffer_head *bh = iloc->bh;
3635 int err = 0, rc, block;
3636
3637 /* For fields not not tracking in the in-memory inode,
3638 * initialise them to zero for new inodes. */
Theodore Ts'o19f5fb72010-01-24 14:34:07 -05003639 if (ext4_test_inode_state(inode, EXT4_STATE_NEW))
Mingming Cao617ba132006-10-11 01:20:53 -07003640 memset(raw_inode, 0, EXT4_SB(inode->i_sb)->s_inode_size);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003641
Jan Karaff9ddf72007-07-18 09:24:20 -04003642 ext4_get_inode_flags(ei);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003643 raw_inode->i_mode = cpu_to_le16(inode->i_mode);
Theodore Ts'oaf5bc922008-09-08 22:25:24 -04003644 if (!(test_opt(inode->i_sb, NO_UID32))) {
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003645 raw_inode->i_uid_low = cpu_to_le16(low_16_bits(inode->i_uid));
3646 raw_inode->i_gid_low = cpu_to_le16(low_16_bits(inode->i_gid));
3647/*
3648 * Fix up interoperability with old kernels. Otherwise, old inodes get
3649 * re-used with the upper 16 bits of the uid/gid intact
3650 */
Theodore Ts'oaf5bc922008-09-08 22:25:24 -04003651 if (!ei->i_dtime) {
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003652 raw_inode->i_uid_high =
3653 cpu_to_le16(high_16_bits(inode->i_uid));
3654 raw_inode->i_gid_high =
3655 cpu_to_le16(high_16_bits(inode->i_gid));
3656 } else {
3657 raw_inode->i_uid_high = 0;
3658 raw_inode->i_gid_high = 0;
3659 }
3660 } else {
3661 raw_inode->i_uid_low =
3662 cpu_to_le16(fs_high2lowuid(inode->i_uid));
3663 raw_inode->i_gid_low =
3664 cpu_to_le16(fs_high2lowgid(inode->i_gid));
3665 raw_inode->i_uid_high = 0;
3666 raw_inode->i_gid_high = 0;
3667 }
3668 raw_inode->i_links_count = cpu_to_le16(inode->i_nlink);
Kalpak Shahef7f3832007-07-18 09:15:20 -04003669
3670 EXT4_INODE_SET_XTIME(i_ctime, inode, raw_inode);
3671 EXT4_INODE_SET_XTIME(i_mtime, inode, raw_inode);
3672 EXT4_INODE_SET_XTIME(i_atime, inode, raw_inode);
3673 EXT4_EINODE_SET_XTIME(i_crtime, ei, raw_inode);
3674
Aneesh Kumar K.V0fc1b452008-01-28 23:58:26 -05003675 if (ext4_inode_blocks_set(handle, raw_inode, ei))
3676 goto out_brelse;
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003677 raw_inode->i_dtime = cpu_to_le32(ei->i_dtime);
Theodore Ts'o353eb832011-01-10 12:18:25 -05003678 raw_inode->i_flags = cpu_to_le32(ei->i_flags & 0xFFFFFFFF);
Mingming Cao9b8f1f02006-10-11 01:21:13 -07003679 if (EXT4_SB(inode->i_sb)->s_es->s_creator_os !=
3680 cpu_to_le32(EXT4_OS_HURD))
Badari Pulavartya1ddeb72006-10-11 01:21:09 -07003681 raw_inode->i_file_acl_high =
3682 cpu_to_le16(ei->i_file_acl >> 32);
Aneesh Kumar K.V7973c0c2008-01-28 23:58:27 -05003683 raw_inode->i_file_acl_lo = cpu_to_le32(ei->i_file_acl);
Aneesh Kumar K.Va48380f2008-01-28 23:58:27 -05003684 ext4_isize_set(raw_inode, ei->i_disksize);
3685 if (ei->i_disksize > 0x7fffffffULL) {
3686 struct super_block *sb = inode->i_sb;
3687 if (!EXT4_HAS_RO_COMPAT_FEATURE(sb,
3688 EXT4_FEATURE_RO_COMPAT_LARGE_FILE) ||
3689 EXT4_SB(sb)->s_es->s_rev_level ==
3690 cpu_to_le32(EXT4_GOOD_OLD_REV)) {
3691 /* If this is the first large file
3692 * created, add a flag to the superblock.
3693 */
3694 err = ext4_journal_get_write_access(handle,
3695 EXT4_SB(sb)->s_sbh);
3696 if (err)
3697 goto out_brelse;
3698 ext4_update_dynamic_rev(sb);
3699 EXT4_SET_RO_COMPAT_FEATURE(sb,
Mingming Cao617ba132006-10-11 01:20:53 -07003700 EXT4_FEATURE_RO_COMPAT_LARGE_FILE);
Aneesh Kumar K.Va48380f2008-01-28 23:58:27 -05003701 sb->s_dirt = 1;
Frank Mayhar03901312009-01-07 00:06:22 -05003702 ext4_handle_sync(handle);
Curt Wohlgemuth73b50c12010-02-16 15:06:29 -05003703 err = ext4_handle_dirty_metadata(handle, NULL,
Aneesh Kumar K.Va48380f2008-01-28 23:58:27 -05003704 EXT4_SB(sb)->s_sbh);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003705 }
3706 }
3707 raw_inode->i_generation = cpu_to_le32(inode->i_generation);
3708 if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) {
3709 if (old_valid_dev(inode->i_rdev)) {
3710 raw_inode->i_block[0] =
3711 cpu_to_le32(old_encode_dev(inode->i_rdev));
3712 raw_inode->i_block[1] = 0;
3713 } else {
3714 raw_inode->i_block[0] = 0;
3715 raw_inode->i_block[1] =
3716 cpu_to_le32(new_encode_dev(inode->i_rdev));
3717 raw_inode->i_block[2] = 0;
3718 }
Theodore Ts'ode9a55b2009-06-14 17:45:34 -04003719 } else
3720 for (block = 0; block < EXT4_N_BLOCKS; block++)
3721 raw_inode->i_block[block] = ei->i_data[block];
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003722
Jean Noel Cordenner25ec56b2008-01-28 23:58:27 -05003723 raw_inode->i_disk_version = cpu_to_le32(inode->i_version);
3724 if (ei->i_extra_isize) {
3725 if (EXT4_FITS_IN_INODE(raw_inode, ei, i_version_hi))
3726 raw_inode->i_version_hi =
3727 cpu_to_le32(inode->i_version >> 32);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003728 raw_inode->i_extra_isize = cpu_to_le16(ei->i_extra_isize);
Jean Noel Cordenner25ec56b2008-01-28 23:58:27 -05003729 }
3730
Frank Mayhar830156c2009-09-29 10:07:47 -04003731 BUFFER_TRACE(bh, "call ext4_handle_dirty_metadata");
Curt Wohlgemuth73b50c12010-02-16 15:06:29 -05003732 rc = ext4_handle_dirty_metadata(handle, NULL, bh);
Frank Mayhar830156c2009-09-29 10:07:47 -04003733 if (!err)
3734 err = rc;
Theodore Ts'o19f5fb72010-01-24 14:34:07 -05003735 ext4_clear_inode_state(inode, EXT4_STATE_NEW);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003736
Jan Karab436b9b2009-12-08 23:51:10 -05003737 ext4_update_inode_fsync_trans(handle, inode, 0);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003738out_brelse:
Theodore Ts'oaf5bc922008-09-08 22:25:24 -04003739 brelse(bh);
Mingming Cao617ba132006-10-11 01:20:53 -07003740 ext4_std_error(inode->i_sb, err);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003741 return err;
3742}
3743
3744/*
Mingming Cao617ba132006-10-11 01:20:53 -07003745 * ext4_write_inode()
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003746 *
3747 * We are called from a few places:
3748 *
3749 * - Within generic_file_write() for O_SYNC files.
3750 * Here, there will be no transaction running. We wait for any running
3751 * trasnaction to commit.
3752 *
3753 * - Within sys_sync(), kupdate and such.
3754 * We wait on commit, if tol to.
3755 *
3756 * - Within prune_icache() (PF_MEMALLOC == true)
3757 * Here we simply return. We can't afford to block kswapd on the
3758 * journal commit.
3759 *
3760 * In all cases it is actually safe for us to return without doing anything,
3761 * because the inode has been copied into a raw inode buffer in
Mingming Cao617ba132006-10-11 01:20:53 -07003762 * ext4_mark_inode_dirty(). This is a correctness thing for O_SYNC and for
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003763 * knfsd.
3764 *
3765 * Note that we are absolutely dependent upon all inode dirtiers doing the
3766 * right thing: they *must* call mark_inode_dirty() after dirtying info in
3767 * which we are interested.
3768 *
3769 * It would be a bug for them to not do this. The code:
3770 *
3771 * mark_inode_dirty(inode)
3772 * stuff();
3773 * inode->i_size = expr;
3774 *
3775 * is in error because a kswapd-driven write_inode() could occur while
3776 * `stuff()' is running, and the new i_size will be lost. Plus the inode
3777 * will no longer be on the superblock's dirty inode list.
3778 */
Christoph Hellwiga9185b42010-03-05 09:21:37 +01003779int ext4_write_inode(struct inode *inode, struct writeback_control *wbc)
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003780{
Frank Mayhar91ac6f42009-09-09 22:33:47 -04003781 int err;
3782
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003783 if (current->flags & PF_MEMALLOC)
3784 return 0;
3785
Frank Mayhar91ac6f42009-09-09 22:33:47 -04003786 if (EXT4_SB(inode->i_sb)->s_journal) {
3787 if (ext4_journal_current_handle()) {
3788 jbd_debug(1, "called recursively, non-PF_MEMALLOC!\n");
3789 dump_stack();
3790 return -EIO;
3791 }
3792
Christoph Hellwiga9185b42010-03-05 09:21:37 +01003793 if (wbc->sync_mode != WB_SYNC_ALL)
Frank Mayhar91ac6f42009-09-09 22:33:47 -04003794 return 0;
3795
3796 err = ext4_force_commit(inode->i_sb);
3797 } else {
3798 struct ext4_iloc iloc;
3799
Curt Wohlgemuth8b472d72010-04-03 16:45:06 -04003800 err = __ext4_get_inode_loc(inode, &iloc, 0);
Frank Mayhar91ac6f42009-09-09 22:33:47 -04003801 if (err)
3802 return err;
Christoph Hellwiga9185b42010-03-05 09:21:37 +01003803 if (wbc->sync_mode == WB_SYNC_ALL)
Frank Mayhar830156c2009-09-29 10:07:47 -04003804 sync_dirty_buffer(iloc.bh);
3805 if (buffer_req(iloc.bh) && !buffer_uptodate(iloc.bh)) {
Theodore Ts'oc398eda2010-07-27 11:56:40 -04003806 EXT4_ERROR_INODE_BLOCK(inode, iloc.bh->b_blocknr,
3807 "IO error syncing inode");
Frank Mayhar830156c2009-09-29 10:07:47 -04003808 err = -EIO;
3809 }
Curt Wohlgemuthfd2dd9f2010-04-03 17:44:16 -04003810 brelse(iloc.bh);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003811 }
Frank Mayhar91ac6f42009-09-09 22:33:47 -04003812 return err;
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003813}
3814
3815/*
Mingming Cao617ba132006-10-11 01:20:53 -07003816 * ext4_setattr()
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003817 *
3818 * Called from notify_change.
3819 *
3820 * We want to trap VFS attempts to truncate the file as soon as
3821 * possible. In particular, we want to make sure that when the VFS
3822 * shrinks i_size, we put the inode on the orphan list and modify
3823 * i_disksize immediately, so that during the subsequent flushing of
3824 * dirty pages and freeing of disk blocks, we can guarantee that any
3825 * commit will leave the blocks being flushed in an unused state on
3826 * disk. (On recovery, the inode will get truncated and the blocks will
3827 * be freed, so we have a strong guarantee that no future commit will
3828 * leave these blocks visible to the user.)
3829 *
Jan Kara678aaf42008-07-11 19:27:31 -04003830 * Another thing we have to assure is that if we are in ordered mode
3831 * and inode is still attached to the committing transaction, we must
3832 * we start writeout of all the dirty pages which are being truncated.
3833 * This way we are sure that all the data written in the previous
3834 * transaction are already on disk (truncate waits for pages under
3835 * writeback).
3836 *
3837 * Called with inode->i_mutex down.
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003838 */
Mingming Cao617ba132006-10-11 01:20:53 -07003839int ext4_setattr(struct dentry *dentry, struct iattr *attr)
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003840{
3841 struct inode *inode = dentry->d_inode;
3842 int error, rc = 0;
Dmitry Monakhov3d287de2010-10-27 22:08:46 -04003843 int orphan = 0;
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003844 const unsigned int ia_valid = attr->ia_valid;
3845
3846 error = inode_change_ok(inode, attr);
3847 if (error)
3848 return error;
3849
Dmitry Monakhov12755622010-04-08 22:04:20 +04003850 if (is_quota_modification(inode, attr))
Christoph Hellwig871a2932010-03-03 09:05:07 -05003851 dquot_initialize(inode);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003852 if ((ia_valid & ATTR_UID && attr->ia_uid != inode->i_uid) ||
3853 (ia_valid & ATTR_GID && attr->ia_gid != inode->i_gid)) {
3854 handle_t *handle;
3855
3856 /* (user+group)*(old+new) structure, inode write (sb,
3857 * inode block, ? - but truncate inode update has it) */
Dmitry Monakhov5aca07e2009-12-08 22:42:15 -05003858 handle = ext4_journal_start(inode, (EXT4_MAXQUOTAS_INIT_BLOCKS(inode->i_sb)+
Dmitry Monakhov194074a2009-12-08 22:42:28 -05003859 EXT4_MAXQUOTAS_DEL_BLOCKS(inode->i_sb))+3);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003860 if (IS_ERR(handle)) {
3861 error = PTR_ERR(handle);
3862 goto err_out;
3863 }
Christoph Hellwigb43fa822010-03-03 09:05:03 -05003864 error = dquot_transfer(inode, attr);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003865 if (error) {
Mingming Cao617ba132006-10-11 01:20:53 -07003866 ext4_journal_stop(handle);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003867 return error;
3868 }
3869 /* Update corresponding info in inode so that everything is in
3870 * one transaction */
3871 if (attr->ia_valid & ATTR_UID)
3872 inode->i_uid = attr->ia_uid;
3873 if (attr->ia_valid & ATTR_GID)
3874 inode->i_gid = attr->ia_gid;
Mingming Cao617ba132006-10-11 01:20:53 -07003875 error = ext4_mark_inode_dirty(handle, inode);
3876 ext4_journal_stop(handle);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003877 }
3878
Eric Sandeene2b46572008-01-28 23:58:27 -05003879 if (attr->ia_valid & ATTR_SIZE) {
Christoph Hellwig562c72a2011-06-24 14:29:45 -04003880 inode_dio_wait(inode);
3881
Dmitry Monakhov12e9b892010-05-16 22:00:00 -04003882 if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))) {
Eric Sandeene2b46572008-01-28 23:58:27 -05003883 struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
3884
Theodore Ts'o0c095c72010-07-27 11:56:06 -04003885 if (attr->ia_size > sbi->s_bitmap_maxbytes)
3886 return -EFBIG;
Eric Sandeene2b46572008-01-28 23:58:27 -05003887 }
3888 }
3889
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003890 if (S_ISREG(inode->i_mode) &&
Jiaying Zhangc8d46e42010-02-24 09:52:53 -05003891 attr->ia_valid & ATTR_SIZE &&
Theodore Ts'o072bd7e2011-05-23 15:13:02 -04003892 (attr->ia_size < inode->i_size)) {
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003893 handle_t *handle;
3894
Mingming Cao617ba132006-10-11 01:20:53 -07003895 handle = ext4_journal_start(inode, 3);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003896 if (IS_ERR(handle)) {
3897 error = PTR_ERR(handle);
3898 goto err_out;
3899 }
Dmitry Monakhov3d287de2010-10-27 22:08:46 -04003900 if (ext4_handle_valid(handle)) {
3901 error = ext4_orphan_add(handle, inode);
3902 orphan = 1;
3903 }
Mingming Cao617ba132006-10-11 01:20:53 -07003904 EXT4_I(inode)->i_disksize = attr->ia_size;
3905 rc = ext4_mark_inode_dirty(handle, inode);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003906 if (!error)
3907 error = rc;
Mingming Cao617ba132006-10-11 01:20:53 -07003908 ext4_journal_stop(handle);
Jan Kara678aaf42008-07-11 19:27:31 -04003909
3910 if (ext4_should_order_data(inode)) {
3911 error = ext4_begin_ordered_truncate(inode,
3912 attr->ia_size);
3913 if (error) {
3914 /* Do as much error cleanup as possible */
3915 handle = ext4_journal_start(inode, 3);
3916 if (IS_ERR(handle)) {
3917 ext4_orphan_del(NULL, inode);
3918 goto err_out;
3919 }
3920 ext4_orphan_del(handle, inode);
Dmitry Monakhov3d287de2010-10-27 22:08:46 -04003921 orphan = 0;
Jan Kara678aaf42008-07-11 19:27:31 -04003922 ext4_journal_stop(handle);
3923 goto err_out;
3924 }
3925 }
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003926 }
3927
Theodore Ts'o072bd7e2011-05-23 15:13:02 -04003928 if (attr->ia_valid & ATTR_SIZE) {
3929 if (attr->ia_size != i_size_read(inode)) {
3930 truncate_setsize(inode, attr->ia_size);
3931 ext4_truncate(inode);
3932 } else if (ext4_test_inode_flag(inode, EXT4_INODE_EOFBLOCKS))
3933 ext4_truncate(inode);
3934 }
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003935
Christoph Hellwig10257742010-06-04 11:30:02 +02003936 if (!rc) {
3937 setattr_copy(inode, attr);
3938 mark_inode_dirty(inode);
3939 }
3940
3941 /*
3942 * If the call to ext4_truncate failed to get a transaction handle at
3943 * all, we need to clean up the in-core orphan list manually.
3944 */
Dmitry Monakhov3d287de2010-10-27 22:08:46 -04003945 if (orphan && inode->i_nlink)
Mingming Cao617ba132006-10-11 01:20:53 -07003946 ext4_orphan_del(NULL, inode);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003947
3948 if (!rc && (ia_valid & ATTR_MODE))
Mingming Cao617ba132006-10-11 01:20:53 -07003949 rc = ext4_acl_chmod(inode);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003950
3951err_out:
Mingming Cao617ba132006-10-11 01:20:53 -07003952 ext4_std_error(inode->i_sb, error);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003953 if (!error)
3954 error = rc;
3955 return error;
3956}
3957
Mingming Cao3e3398a2008-07-11 19:27:31 -04003958int ext4_getattr(struct vfsmount *mnt, struct dentry *dentry,
3959 struct kstat *stat)
3960{
3961 struct inode *inode;
3962 unsigned long delalloc_blocks;
3963
3964 inode = dentry->d_inode;
3965 generic_fillattr(inode, stat);
3966
3967 /*
3968 * We can't update i_blocks if the block allocation is delayed
3969 * otherwise in the case of system crash before the real block
3970 * allocation is done, we will have i_blocks inconsistent with
3971 * on-disk file blocks.
3972 * We always keep i_blocks updated together with real
3973 * allocation. But to not confuse with user, stat
3974 * will return the blocks that include the delayed allocation
3975 * blocks for this file.
3976 */
Mingming Cao3e3398a2008-07-11 19:27:31 -04003977 delalloc_blocks = EXT4_I(inode)->i_reserved_data_blocks;
Mingming Cao3e3398a2008-07-11 19:27:31 -04003978
3979 stat->blocks += (delalloc_blocks << inode->i_sb->s_blocksize_bits)>>9;
3980 return 0;
3981}
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003982
Mingming Caoa02908f2008-08-19 22:16:07 -04003983static int ext4_index_trans_blocks(struct inode *inode, int nrblocks, int chunk)
3984{
Dmitry Monakhov12e9b892010-05-16 22:00:00 -04003985 if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)))
Amir Goldstein8bb2b242011-06-27 17:10:28 -04003986 return ext4_ind_trans_blocks(inode, nrblocks, chunk);
Theodore Ts'oac51d832008-11-06 16:49:36 -05003987 return ext4_ext_index_trans_blocks(inode, nrblocks, chunk);
Mingming Caoa02908f2008-08-19 22:16:07 -04003988}
Theodore Ts'oac51d832008-11-06 16:49:36 -05003989
Mingming Caoa02908f2008-08-19 22:16:07 -04003990/*
3991 * Account for index blocks, block groups bitmaps and block group
3992 * descriptor blocks if modify datablocks and index blocks
3993 * worse case, the indexs blocks spread over different block groups
3994 *
3995 * If datablocks are discontiguous, they are possible to spread over
André Goddard Rosaaf901ca2009-11-14 13:09:05 -02003996 * different block groups too. If they are contiuguous, with flexbg,
Mingming Caoa02908f2008-08-19 22:16:07 -04003997 * they could still across block group boundary.
3998 *
3999 * Also account for superblock, inode, quota and xattr blocks
4000 */
Theodore Ts'o1f109d52010-10-27 21:30:14 -04004001static int ext4_meta_trans_blocks(struct inode *inode, int nrblocks, int chunk)
Mingming Caoa02908f2008-08-19 22:16:07 -04004002{
Theodore Ts'o8df96752009-05-01 08:50:38 -04004003 ext4_group_t groups, ngroups = ext4_get_groups_count(inode->i_sb);
4004 int gdpblocks;
Mingming Caoa02908f2008-08-19 22:16:07 -04004005 int idxblocks;
4006 int ret = 0;
4007
4008 /*
4009 * How many index blocks need to touch to modify nrblocks?
4010 * The "Chunk" flag indicating whether the nrblocks is
4011 * physically contiguous on disk
4012 *
4013 * For Direct IO and fallocate, they calls get_block to allocate
4014 * one single extent at a time, so they could set the "Chunk" flag
4015 */
4016 idxblocks = ext4_index_trans_blocks(inode, nrblocks, chunk);
4017
4018 ret = idxblocks;
4019
4020 /*
4021 * Now let's see how many group bitmaps and group descriptors need
4022 * to account
4023 */
4024 groups = idxblocks;
4025 if (chunk)
4026 groups += 1;
Dave Kleikampac27a0e2006-10-11 01:20:50 -07004027 else
Mingming Caoa02908f2008-08-19 22:16:07 -04004028 groups += nrblocks;
Dave Kleikampac27a0e2006-10-11 01:20:50 -07004029
Mingming Caoa02908f2008-08-19 22:16:07 -04004030 gdpblocks = groups;
Theodore Ts'o8df96752009-05-01 08:50:38 -04004031 if (groups > ngroups)
4032 groups = ngroups;
Mingming Caoa02908f2008-08-19 22:16:07 -04004033 if (groups > EXT4_SB(inode->i_sb)->s_gdb_count)
4034 gdpblocks = EXT4_SB(inode->i_sb)->s_gdb_count;
4035
4036 /* bitmaps and block group descriptor blocks */
4037 ret += groups + gdpblocks;
4038
4039 /* Blocks for super block, inode, quota and xattr blocks */
4040 ret += EXT4_META_TRANS_BLOCKS(inode->i_sb);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07004041
4042 return ret;
4043}
4044
4045/*
Lucas De Marchi25985ed2011-03-30 22:57:33 -03004046 * Calculate the total number of credits to reserve to fit
Mingming Caof3bd1f32008-08-19 22:16:03 -04004047 * the modification of a single pages into a single transaction,
4048 * which may include multiple chunks of block allocations.
Mingming Caoa02908f2008-08-19 22:16:07 -04004049 *
Mingming Cao525f4ed2008-08-19 22:15:58 -04004050 * This could be called via ext4_write_begin()
Mingming Caoa02908f2008-08-19 22:16:07 -04004051 *
Mingming Cao525f4ed2008-08-19 22:15:58 -04004052 * We need to consider the worse case, when
Mingming Caoa02908f2008-08-19 22:16:07 -04004053 * one new block per extent.
Mingming Caoa02908f2008-08-19 22:16:07 -04004054 */
4055int ext4_writepage_trans_blocks(struct inode *inode)
4056{
4057 int bpp = ext4_journal_blocks_per_page(inode);
4058 int ret;
4059
4060 ret = ext4_meta_trans_blocks(inode, bpp, 0);
4061
4062 /* Account for data blocks for journalled mode */
4063 if (ext4_should_journal_data(inode))
4064 ret += bpp;
4065 return ret;
4066}
Mingming Caof3bd1f32008-08-19 22:16:03 -04004067
4068/*
4069 * Calculate the journal credits for a chunk of data modification.
4070 *
4071 * This is called from DIO, fallocate or whoever calling
Eric Sandeen79e83032010-07-27 11:56:07 -04004072 * ext4_map_blocks() to map/allocate a chunk of contiguous disk blocks.
Mingming Caof3bd1f32008-08-19 22:16:03 -04004073 *
4074 * journal buffers for data blocks are not included here, as DIO
4075 * and fallocate do no need to journal data buffers.
4076 */
4077int ext4_chunk_trans_blocks(struct inode *inode, int nrblocks)
4078{
4079 return ext4_meta_trans_blocks(inode, nrblocks, 1);
4080}
4081
Mingming Caoa02908f2008-08-19 22:16:07 -04004082/*
Mingming Cao617ba132006-10-11 01:20:53 -07004083 * The caller must have previously called ext4_reserve_inode_write().
Dave Kleikampac27a0e2006-10-11 01:20:50 -07004084 * Give this, we know that the caller already has write access to iloc->bh.
4085 */
Mingming Cao617ba132006-10-11 01:20:53 -07004086int ext4_mark_iloc_dirty(handle_t *handle,
Theodore Ts'ode9a55b2009-06-14 17:45:34 -04004087 struct inode *inode, struct ext4_iloc *iloc)
Dave Kleikampac27a0e2006-10-11 01:20:50 -07004088{
4089 int err = 0;
4090
Jean Noel Cordenner25ec56b2008-01-28 23:58:27 -05004091 if (test_opt(inode->i_sb, I_VERSION))
4092 inode_inc_iversion(inode);
4093
Dave Kleikampac27a0e2006-10-11 01:20:50 -07004094 /* the do_update_inode consumes one bh->b_count */
4095 get_bh(iloc->bh);
4096
Mingming Caodab291a2006-10-11 01:21:01 -07004097 /* ext4_do_update_inode() does jbd2_journal_dirty_metadata */
Frank Mayhar830156c2009-09-29 10:07:47 -04004098 err = ext4_do_update_inode(handle, inode, iloc);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07004099 put_bh(iloc->bh);
4100 return err;
4101}
4102
4103/*
4104 * On success, We end up with an outstanding reference count against
4105 * iloc->bh. This _must_ be cleaned up later.
4106 */
4107
4108int
Mingming Cao617ba132006-10-11 01:20:53 -07004109ext4_reserve_inode_write(handle_t *handle, struct inode *inode,
4110 struct ext4_iloc *iloc)
Dave Kleikampac27a0e2006-10-11 01:20:50 -07004111{
Frank Mayhar03901312009-01-07 00:06:22 -05004112 int err;
4113
4114 err = ext4_get_inode_loc(inode, iloc);
4115 if (!err) {
4116 BUFFER_TRACE(iloc->bh, "get_write_access");
4117 err = ext4_journal_get_write_access(handle, iloc->bh);
4118 if (err) {
4119 brelse(iloc->bh);
4120 iloc->bh = NULL;
Dave Kleikampac27a0e2006-10-11 01:20:50 -07004121 }
4122 }
Mingming Cao617ba132006-10-11 01:20:53 -07004123 ext4_std_error(inode->i_sb, err);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07004124 return err;
4125}
4126
4127/*
Kalpak Shah6dd4ee72007-07-18 09:19:57 -04004128 * Expand an inode by new_extra_isize bytes.
4129 * Returns 0 on success or negative error number on failure.
4130 */
Aneesh Kumar K.V1d03ec92008-01-28 23:58:27 -05004131static int ext4_expand_extra_isize(struct inode *inode,
4132 unsigned int new_extra_isize,
4133 struct ext4_iloc iloc,
4134 handle_t *handle)
Kalpak Shah6dd4ee72007-07-18 09:19:57 -04004135{
4136 struct ext4_inode *raw_inode;
4137 struct ext4_xattr_ibody_header *header;
Kalpak Shah6dd4ee72007-07-18 09:19:57 -04004138
4139 if (EXT4_I(inode)->i_extra_isize >= new_extra_isize)
4140 return 0;
4141
4142 raw_inode = ext4_raw_inode(&iloc);
4143
4144 header = IHDR(inode, raw_inode);
Kalpak Shah6dd4ee72007-07-18 09:19:57 -04004145
4146 /* No extended attributes present */
Theodore Ts'o19f5fb72010-01-24 14:34:07 -05004147 if (!ext4_test_inode_state(inode, EXT4_STATE_XATTR) ||
4148 header->h_magic != cpu_to_le32(EXT4_XATTR_MAGIC)) {
Kalpak Shah6dd4ee72007-07-18 09:19:57 -04004149 memset((void *)raw_inode + EXT4_GOOD_OLD_INODE_SIZE, 0,
4150 new_extra_isize);
4151 EXT4_I(inode)->i_extra_isize = new_extra_isize;
4152 return 0;
4153 }
4154
4155 /* try to expand with EAs present */
4156 return ext4_expand_extra_isize_ea(inode, new_extra_isize,
4157 raw_inode, handle);
4158}
4159
4160/*
Dave Kleikampac27a0e2006-10-11 01:20:50 -07004161 * What we do here is to mark the in-core inode as clean with respect to inode
4162 * dirtiness (it may still be data-dirty).
4163 * This means that the in-core inode may be reaped by prune_icache
4164 * without having to perform any I/O. This is a very good thing,
4165 * because *any* task may call prune_icache - even ones which
4166 * have a transaction open against a different journal.
4167 *
4168 * Is this cheating? Not really. Sure, we haven't written the
4169 * inode out, but prune_icache isn't a user-visible syncing function.
4170 * Whenever the user wants stuff synced (sys_sync, sys_msync, sys_fsync)
4171 * we start and wait on commits.
4172 *
4173 * Is this efficient/effective? Well, we're being nice to the system
4174 * by cleaning up our inodes proactively so they can be reaped
4175 * without I/O. But we are potentially leaving up to five seconds'
4176 * worth of inodes floating about which prune_icache wants us to
4177 * write out. One way to fix that would be to get prune_icache()
4178 * to do a write_super() to free up some memory. It has the desired
4179 * effect.
4180 */
Mingming Cao617ba132006-10-11 01:20:53 -07004181int ext4_mark_inode_dirty(handle_t *handle, struct inode *inode)
Dave Kleikampac27a0e2006-10-11 01:20:50 -07004182{
Mingming Cao617ba132006-10-11 01:20:53 -07004183 struct ext4_iloc iloc;
Kalpak Shah6dd4ee72007-07-18 09:19:57 -04004184 struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
4185 static unsigned int mnt_count;
4186 int err, ret;
Dave Kleikampac27a0e2006-10-11 01:20:50 -07004187
4188 might_sleep();
Theodore Ts'o7ff9c072010-11-08 13:51:33 -05004189 trace_ext4_mark_inode_dirty(inode, _RET_IP_);
Mingming Cao617ba132006-10-11 01:20:53 -07004190 err = ext4_reserve_inode_write(handle, inode, &iloc);
Frank Mayhar03901312009-01-07 00:06:22 -05004191 if (ext4_handle_valid(handle) &&
4192 EXT4_I(inode)->i_extra_isize < sbi->s_want_extra_isize &&
Theodore Ts'o19f5fb72010-01-24 14:34:07 -05004193 !ext4_test_inode_state(inode, EXT4_STATE_NO_EXPAND)) {
Kalpak Shah6dd4ee72007-07-18 09:19:57 -04004194 /*
4195 * We need extra buffer credits since we may write into EA block
4196 * with this same handle. If journal_extend fails, then it will
4197 * only result in a minor loss of functionality for that inode.
4198 * If this is felt to be critical, then e2fsck should be run to
4199 * force a large enough s_min_extra_isize.
4200 */
4201 if ((jbd2_journal_extend(handle,
4202 EXT4_DATA_TRANS_BLOCKS(inode->i_sb))) == 0) {
4203 ret = ext4_expand_extra_isize(inode,
4204 sbi->s_want_extra_isize,
4205 iloc, handle);
4206 if (ret) {
Theodore Ts'o19f5fb72010-01-24 14:34:07 -05004207 ext4_set_inode_state(inode,
4208 EXT4_STATE_NO_EXPAND);
Aneesh Kumar K.Vc1bddad2007-10-16 18:38:25 -04004209 if (mnt_count !=
4210 le16_to_cpu(sbi->s_es->s_mnt_count)) {
Eric Sandeen12062dd2010-02-15 14:19:27 -05004211 ext4_warning(inode->i_sb,
Kalpak Shah6dd4ee72007-07-18 09:19:57 -04004212 "Unable to expand inode %lu. Delete"
4213 " some EAs or run e2fsck.",
4214 inode->i_ino);
Aneesh Kumar K.Vc1bddad2007-10-16 18:38:25 -04004215 mnt_count =
4216 le16_to_cpu(sbi->s_es->s_mnt_count);
Kalpak Shah6dd4ee72007-07-18 09:19:57 -04004217 }
4218 }
4219 }
4220 }
Dave Kleikampac27a0e2006-10-11 01:20:50 -07004221 if (!err)
Mingming Cao617ba132006-10-11 01:20:53 -07004222 err = ext4_mark_iloc_dirty(handle, inode, &iloc);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07004223 return err;
4224}
4225
4226/*
Mingming Cao617ba132006-10-11 01:20:53 -07004227 * ext4_dirty_inode() is called from __mark_inode_dirty()
Dave Kleikampac27a0e2006-10-11 01:20:50 -07004228 *
4229 * We're really interested in the case where a file is being extended.
4230 * i_size has been changed by generic_commit_write() and we thus need
4231 * to include the updated inode in the current transaction.
4232 *
Christoph Hellwig5dd40562010-03-03 09:05:00 -05004233 * Also, dquot_alloc_block() will always dirty the inode when blocks
Dave Kleikampac27a0e2006-10-11 01:20:50 -07004234 * are allocated to the file.
4235 *
4236 * If the inode is marked synchronous, we don't honour that here - doing
4237 * so would cause a commit on atime updates, which we don't bother doing.
4238 * We handle synchronous inodes at the highest possible level.
4239 */
Christoph Hellwigaa385722011-05-27 06:53:02 -04004240void ext4_dirty_inode(struct inode *inode, int flags)
Dave Kleikampac27a0e2006-10-11 01:20:50 -07004241{
Dave Kleikampac27a0e2006-10-11 01:20:50 -07004242 handle_t *handle;
4243
Mingming Cao617ba132006-10-11 01:20:53 -07004244 handle = ext4_journal_start(inode, 2);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07004245 if (IS_ERR(handle))
4246 goto out;
Curt Wohlgemuthf3dc2722009-09-29 16:06:01 -04004247
Curt Wohlgemuthf3dc2722009-09-29 16:06:01 -04004248 ext4_mark_inode_dirty(handle, inode);
4249
Mingming Cao617ba132006-10-11 01:20:53 -07004250 ext4_journal_stop(handle);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07004251out:
4252 return;
4253}
4254
4255#if 0
4256/*
4257 * Bind an inode's backing buffer_head into this transaction, to prevent
4258 * it from being flushed to disk early. Unlike
Mingming Cao617ba132006-10-11 01:20:53 -07004259 * ext4_reserve_inode_write, this leaves behind no bh reference and
Dave Kleikampac27a0e2006-10-11 01:20:50 -07004260 * returns no iloc structure, so the caller needs to repeat the iloc
4261 * lookup to mark the inode dirty later.
4262 */
Mingming Cao617ba132006-10-11 01:20:53 -07004263static int ext4_pin_inode(handle_t *handle, struct inode *inode)
Dave Kleikampac27a0e2006-10-11 01:20:50 -07004264{
Mingming Cao617ba132006-10-11 01:20:53 -07004265 struct ext4_iloc iloc;
Dave Kleikampac27a0e2006-10-11 01:20:50 -07004266
4267 int err = 0;
4268 if (handle) {
Mingming Cao617ba132006-10-11 01:20:53 -07004269 err = ext4_get_inode_loc(inode, &iloc);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07004270 if (!err) {
4271 BUFFER_TRACE(iloc.bh, "get_write_access");
Mingming Caodab291a2006-10-11 01:21:01 -07004272 err = jbd2_journal_get_write_access(handle, iloc.bh);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07004273 if (!err)
Frank Mayhar03901312009-01-07 00:06:22 -05004274 err = ext4_handle_dirty_metadata(handle,
Curt Wohlgemuth73b50c12010-02-16 15:06:29 -05004275 NULL,
Frank Mayhar03901312009-01-07 00:06:22 -05004276 iloc.bh);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07004277 brelse(iloc.bh);
4278 }
4279 }
Mingming Cao617ba132006-10-11 01:20:53 -07004280 ext4_std_error(inode->i_sb, err);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07004281 return err;
4282}
4283#endif
4284
Mingming Cao617ba132006-10-11 01:20:53 -07004285int ext4_change_inode_journal_flag(struct inode *inode, int val)
Dave Kleikampac27a0e2006-10-11 01:20:50 -07004286{
4287 journal_t *journal;
4288 handle_t *handle;
4289 int err;
4290
4291 /*
4292 * We have to be very careful here: changing a data block's
4293 * journaling status dynamically is dangerous. If we write a
4294 * data block to the journal, change the status and then delete
4295 * that block, we risk forgetting to revoke the old log record
4296 * from the journal and so a subsequent replay can corrupt data.
4297 * So, first we make sure that the journal is empty and that
4298 * nobody is changing anything.
4299 */
4300
Mingming Cao617ba132006-10-11 01:20:53 -07004301 journal = EXT4_JOURNAL(inode);
Frank Mayhar03901312009-01-07 00:06:22 -05004302 if (!journal)
4303 return 0;
Dave Hansend6995942007-07-18 08:33:51 -04004304 if (is_journal_aborted(journal))
Dave Kleikampac27a0e2006-10-11 01:20:50 -07004305 return -EROFS;
4306
Mingming Caodab291a2006-10-11 01:21:01 -07004307 jbd2_journal_lock_updates(journal);
4308 jbd2_journal_flush(journal);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07004309
4310 /*
4311 * OK, there are no updates running now, and all cached data is
4312 * synced to disk. We are now in a completely consistent state
4313 * which doesn't have anything in the journal, and we know that
4314 * no filesystem updates are running, so it is safe to modify
4315 * the inode's in-core data-journaling state flag now.
4316 */
4317
4318 if (val)
Dmitry Monakhov12e9b892010-05-16 22:00:00 -04004319 ext4_set_inode_flag(inode, EXT4_INODE_JOURNAL_DATA);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07004320 else
Dmitry Monakhov12e9b892010-05-16 22:00:00 -04004321 ext4_clear_inode_flag(inode, EXT4_INODE_JOURNAL_DATA);
Mingming Cao617ba132006-10-11 01:20:53 -07004322 ext4_set_aops(inode);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07004323
Mingming Caodab291a2006-10-11 01:21:01 -07004324 jbd2_journal_unlock_updates(journal);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07004325
4326 /* Finally we can mark the inode as dirty. */
4327
Mingming Cao617ba132006-10-11 01:20:53 -07004328 handle = ext4_journal_start(inode, 1);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07004329 if (IS_ERR(handle))
4330 return PTR_ERR(handle);
4331
Mingming Cao617ba132006-10-11 01:20:53 -07004332 err = ext4_mark_inode_dirty(handle, inode);
Frank Mayhar03901312009-01-07 00:06:22 -05004333 ext4_handle_sync(handle);
Mingming Cao617ba132006-10-11 01:20:53 -07004334 ext4_journal_stop(handle);
4335 ext4_std_error(inode->i_sb, err);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07004336
4337 return err;
4338}
Aneesh Kumar K.V2e9ee852008-07-11 19:27:31 -04004339
4340static int ext4_bh_unmapped(handle_t *handle, struct buffer_head *bh)
4341{
4342 return !buffer_mapped(bh);
4343}
4344
Nick Pigginc2ec1752009-03-31 15:23:21 -07004345int ext4_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf)
Aneesh Kumar K.V2e9ee852008-07-11 19:27:31 -04004346{
Nick Pigginc2ec1752009-03-31 15:23:21 -07004347 struct page *page = vmf->page;
Aneesh Kumar K.V2e9ee852008-07-11 19:27:31 -04004348 loff_t size;
4349 unsigned long len;
Jan Kara9ea7df52011-06-24 14:29:41 -04004350 int ret;
Aneesh Kumar K.V2e9ee852008-07-11 19:27:31 -04004351 struct file *file = vma->vm_file;
4352 struct inode *inode = file->f_path.dentry->d_inode;
4353 struct address_space *mapping = inode->i_mapping;
Jan Kara9ea7df52011-06-24 14:29:41 -04004354 handle_t *handle;
4355 get_block_t *get_block;
4356 int retries = 0;
Aneesh Kumar K.V2e9ee852008-07-11 19:27:31 -04004357
4358 /*
Jan Kara9ea7df52011-06-24 14:29:41 -04004359 * This check is racy but catches the common case. We rely on
4360 * __block_page_mkwrite() to do a reliable check.
Aneesh Kumar K.V2e9ee852008-07-11 19:27:31 -04004361 */
Jan Kara9ea7df52011-06-24 14:29:41 -04004362 vfs_check_frozen(inode->i_sb, SB_FREEZE_WRITE);
4363 /* Delalloc case is easy... */
4364 if (test_opt(inode->i_sb, DELALLOC) &&
4365 !ext4_should_journal_data(inode) &&
4366 !ext4_nonda_switch(inode->i_sb)) {
4367 do {
4368 ret = __block_page_mkwrite(vma, vmf,
4369 ext4_da_get_block_prep);
4370 } while (ret == -ENOSPC &&
4371 ext4_should_retry_alloc(inode->i_sb, &retries));
4372 goto out_ret;
Aneesh Kumar K.V2e9ee852008-07-11 19:27:31 -04004373 }
Darrick J. Wong0e499892011-05-18 13:55:20 -04004374
4375 lock_page(page);
Jan Kara9ea7df52011-06-24 14:29:41 -04004376 size = i_size_read(inode);
4377 /* Page got truncated from under us? */
4378 if (page->mapping != mapping || page_offset(page) > size) {
4379 unlock_page(page);
4380 ret = VM_FAULT_NOPAGE;
4381 goto out;
Darrick J. Wong0e499892011-05-18 13:55:20 -04004382 }
Aneesh Kumar K.V2e9ee852008-07-11 19:27:31 -04004383
4384 if (page->index == size >> PAGE_CACHE_SHIFT)
4385 len = size & ~PAGE_CACHE_MASK;
4386 else
4387 len = PAGE_CACHE_SIZE;
Aneesh Kumar K.Va827eaf2009-09-09 22:36:03 -04004388 /*
Jan Kara9ea7df52011-06-24 14:29:41 -04004389 * Return if we have all the buffers mapped. This avoids the need to do
4390 * journal_start/journal_stop which can block and take a long time
Aneesh Kumar K.Va827eaf2009-09-09 22:36:03 -04004391 */
Aneesh Kumar K.V2e9ee852008-07-11 19:27:31 -04004392 if (page_has_buffers(page)) {
Aneesh Kumar K.V2e9ee852008-07-11 19:27:31 -04004393 if (!walk_page_buffers(NULL, page_buffers(page), 0, len, NULL,
Aneesh Kumar K.Va827eaf2009-09-09 22:36:03 -04004394 ext4_bh_unmapped)) {
Jan Kara9ea7df52011-06-24 14:29:41 -04004395 /* Wait so that we don't change page under IO */
4396 wait_on_page_writeback(page);
4397 ret = VM_FAULT_LOCKED;
4398 goto out;
Aneesh Kumar K.Va827eaf2009-09-09 22:36:03 -04004399 }
Aneesh Kumar K.V2e9ee852008-07-11 19:27:31 -04004400 }
Aneesh Kumar K.Va827eaf2009-09-09 22:36:03 -04004401 unlock_page(page);
Jan Kara9ea7df52011-06-24 14:29:41 -04004402 /* OK, we need to fill the hole... */
4403 if (ext4_should_dioread_nolock(inode))
4404 get_block = ext4_get_block_write;
4405 else
4406 get_block = ext4_get_block;
4407retry_alloc:
4408 handle = ext4_journal_start(inode, ext4_writepage_trans_blocks(inode));
4409 if (IS_ERR(handle)) {
Nick Pigginc2ec1752009-03-31 15:23:21 -07004410 ret = VM_FAULT_SIGBUS;
Jan Kara9ea7df52011-06-24 14:29:41 -04004411 goto out;
4412 }
4413 ret = __block_page_mkwrite(vma, vmf, get_block);
4414 if (!ret && ext4_should_journal_data(inode)) {
4415 if (walk_page_buffers(handle, page_buffers(page), 0,
4416 PAGE_CACHE_SIZE, NULL, do_journal_get_write_access)) {
4417 unlock_page(page);
4418 ret = VM_FAULT_SIGBUS;
4419 goto out;
4420 }
4421 ext4_set_inode_state(inode, EXT4_STATE_JDATA);
4422 }
4423 ext4_journal_stop(handle);
4424 if (ret == -ENOSPC && ext4_should_retry_alloc(inode->i_sb, &retries))
4425 goto retry_alloc;
4426out_ret:
4427 ret = block_page_mkwrite_return(ret);
4428out:
Aneesh Kumar K.V2e9ee852008-07-11 19:27:31 -04004429 return ret;
4430}