blob: 3451d23c3bae3eedd75d8504694a22735e7dc291 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * linux/fs/ext3/inode.c
3 *
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 *
15 * Goal-directed block allocation by Stephen Tweedie
Dave Kleikampe9ad5622006-09-27 01:49:35 -070016 * (sct@redhat.com), 1993, 1998
Linus Torvalds1da177e2005-04-16 15:20:36 -070017 * Big-endian to little-endian byte-swapping/bitmaps by
18 * David S. Miller (davem@caip.rutgers.edu), 1995
19 * 64-bit file support on 64-bit platforms by Jakub Jelinek
Dave Kleikampe9ad5622006-09-27 01:49:35 -070020 * (jj@sunsite.ms.mff.cuni.cz)
Linus Torvalds1da177e2005-04-16 15:20:36 -070021 *
22 * Assorted race fixes, rewrite of ext3_get_block() by Al Viro, 2000
23 */
24
25#include <linux/module.h>
26#include <linux/fs.h>
27#include <linux/time.h>
28#include <linux/ext3_jbd.h>
29#include <linux/jbd.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070030#include <linux/highuid.h>
31#include <linux/pagemap.h>
32#include <linux/quotaops.h>
33#include <linux/string.h>
34#include <linux/buffer_head.h>
35#include <linux/writeback.h>
36#include <linux/mpage.h>
37#include <linux/uio.h>
Jens Axboecaa38fb2006-07-23 01:41:26 +020038#include <linux/bio.h>
Josef Bacik68c9d702008-10-03 17:32:43 -040039#include <linux/fiemap.h>
Duane Griffinb5ed3112008-12-19 20:47:14 +000040#include <linux/namei.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070041#include "xattr.h"
42#include "acl.h"
43
44static int ext3_writepage_trans_blocks(struct inode *inode);
45
46/*
47 * Test whether an inode is a fast symlink.
48 */
Andrew Mortond6859bf2006-03-26 01:38:03 -080049static int ext3_inode_is_fast_symlink(struct inode *inode)
Linus Torvalds1da177e2005-04-16 15:20:36 -070050{
51 int ea_blocks = EXT3_I(inode)->i_file_acl ?
52 (inode->i_sb->s_blocksize >> 9) : 0;
53
Andrew Mortond6859bf2006-03-26 01:38:03 -080054 return (S_ISLNK(inode->i_mode) && inode->i_blocks - ea_blocks == 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -070055}
56
Andrew Mortond6859bf2006-03-26 01:38:03 -080057/*
58 * The ext3 forget function must perform a revoke if we are freeing data
Linus Torvalds1da177e2005-04-16 15:20:36 -070059 * which has been journaled. Metadata (eg. indirect blocks) must be
Mingming Caoae6ddcc2006-09-27 01:49:27 -070060 * revoked in all cases.
Linus Torvalds1da177e2005-04-16 15:20:36 -070061 *
62 * "bh" may be NULL: a metadata block may have been freed from memory
63 * but there may still be a record of it in the journal, and that record
64 * still needs to be revoked.
65 */
Andrew Mortond6859bf2006-03-26 01:38:03 -080066int ext3_forget(handle_t *handle, int is_metadata, struct inode *inode,
Mingming Cao1c2bf372006-06-25 05:48:06 -070067 struct buffer_head *bh, ext3_fsblk_t blocknr)
Linus Torvalds1da177e2005-04-16 15:20:36 -070068{
69 int err;
70
71 might_sleep();
72
73 BUFFER_TRACE(bh, "enter");
74
75 jbd_debug(4, "forgetting bh %p: is_metadata = %d, mode %o, "
76 "data mode %lx\n",
77 bh, is_metadata, inode->i_mode,
78 test_opt(inode->i_sb, DATA_FLAGS));
79
80 /* Never use the revoke function if we are doing full data
81 * journaling: there is no need to, and a V1 superblock won't
82 * support it. Otherwise, only skip the revoke on un-journaled
83 * data blocks. */
84
85 if (test_opt(inode->i_sb, DATA_FLAGS) == EXT3_MOUNT_JOURNAL_DATA ||
86 (!is_metadata && !ext3_should_journal_data(inode))) {
87 if (bh) {
88 BUFFER_TRACE(bh, "call journal_forget");
89 return ext3_journal_forget(handle, bh);
90 }
91 return 0;
92 }
93
94 /*
95 * data!=journal && (is_metadata || should_journal_data(inode))
96 */
97 BUFFER_TRACE(bh, "call ext3_journal_revoke");
98 err = ext3_journal_revoke(handle, blocknr, bh);
99 if (err)
Harvey Harrisone05b6b52008-04-28 02:16:15 -0700100 ext3_abort(inode->i_sb, __func__,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700101 "error %d when attempting revoke", err);
102 BUFFER_TRACE(bh, "exit");
103 return err;
104}
105
106/*
Andrew Mortond6859bf2006-03-26 01:38:03 -0800107 * Work out how many blocks we need to proceed with the next chunk of a
Linus Torvalds1da177e2005-04-16 15:20:36 -0700108 * truncate transaction.
109 */
Mingming Caoae6ddcc2006-09-27 01:49:27 -0700110static unsigned long blocks_for_truncate(struct inode *inode)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700111{
112 unsigned long needed;
113
114 needed = inode->i_blocks >> (inode->i_sb->s_blocksize_bits - 9);
115
116 /* Give ourselves just enough room to cope with inodes in which
117 * i_blocks is corrupt: we've seen disk corruptions in the past
118 * which resulted in random data in an inode which looked enough
119 * like a regular file for ext3 to try to delete it. Things
120 * will go a bit crazy if that happens, but at least we should
121 * try not to panic the whole kernel. */
122 if (needed < 2)
123 needed = 2;
124
125 /* But we need to bound the transaction so we don't overflow the
126 * journal. */
Mingming Caoae6ddcc2006-09-27 01:49:27 -0700127 if (needed > EXT3_MAX_TRANS_DATA)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700128 needed = EXT3_MAX_TRANS_DATA;
129
Jan Kara1f545872005-06-23 22:01:04 -0700130 return EXT3_DATA_TRANS_BLOCKS(inode->i_sb) + needed;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700131}
132
Mingming Caoae6ddcc2006-09-27 01:49:27 -0700133/*
Linus Torvalds1da177e2005-04-16 15:20:36 -0700134 * Truncate transactions can be complex and absolutely huge. So we need to
135 * be able to restart the transaction at a conventient checkpoint to make
136 * sure we don't overflow the journal.
137 *
138 * start_transaction gets us a new handle for a truncate transaction,
139 * and extend_transaction tries to extend the existing one a bit. If
140 * extend fails, we need to propagate the failure up and restart the
Mingming Caoae6ddcc2006-09-27 01:49:27 -0700141 * transaction in the top-level truncate loop. --sct
Linus Torvalds1da177e2005-04-16 15:20:36 -0700142 */
Mingming Caoae6ddcc2006-09-27 01:49:27 -0700143static handle_t *start_transaction(struct inode *inode)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700144{
145 handle_t *result;
146
147 result = ext3_journal_start(inode, blocks_for_truncate(inode));
148 if (!IS_ERR(result))
149 return result;
150
151 ext3_std_error(inode->i_sb, PTR_ERR(result));
152 return result;
153}
154
155/*
156 * Try to extend this transaction for the purposes of truncation.
157 *
158 * Returns 0 if we managed to create more room. If we can't create more
159 * room, and the transaction must be restarted we return 1.
160 */
161static int try_to_extend_transaction(handle_t *handle, struct inode *inode)
162{
163 if (handle->h_buffer_credits > EXT3_RESERVE_TRANS_BLOCKS)
164 return 0;
165 if (!ext3_journal_extend(handle, blocks_for_truncate(inode)))
166 return 0;
167 return 1;
168}
169
170/*
171 * Restart the transaction associated with *handle. This does a commit,
172 * so before we call here everything must be consistently dirtied against
173 * this transaction.
174 */
Jan Kara00171d32009-08-11 19:06:10 +0200175static int truncate_restart_transaction(handle_t *handle, struct inode *inode)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700176{
Jan Kara00171d32009-08-11 19:06:10 +0200177 int ret;
178
Linus Torvalds1da177e2005-04-16 15:20:36 -0700179 jbd_debug(2, "restarting handle %p\n", handle);
Jan Kara00171d32009-08-11 19:06:10 +0200180 /*
181 * Drop truncate_mutex to avoid deadlock with ext3_get_blocks_handle
182 * At this moment, get_block can be called only for blocks inside
183 * i_size since page cache has been already dropped and writes are
184 * blocked by i_mutex. So we can safely drop the truncate_mutex.
185 */
186 mutex_unlock(&EXT3_I(inode)->truncate_mutex);
187 ret = ext3_journal_restart(handle, blocks_for_truncate(inode));
188 mutex_lock(&EXT3_I(inode)->truncate_mutex);
189 return ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700190}
191
192/*
Al Viroac14a952010-06-06 07:08:19 -0400193 * Called at inode eviction from icache
Linus Torvalds1da177e2005-04-16 15:20:36 -0700194 */
Al Viroac14a952010-06-06 07:08:19 -0400195void ext3_evict_inode (struct inode *inode)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700196{
Al Viroac14a952010-06-06 07:08:19 -0400197 struct ext3_block_alloc_info *rsv;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700198 handle_t *handle;
Al Viroac14a952010-06-06 07:08:19 -0400199 int want_delete = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700200
Al Viroac14a952010-06-06 07:08:19 -0400201 if (!inode->i_nlink && !is_bad_inode(inode)) {
Christoph Hellwig871a2932010-03-03 09:05:07 -0500202 dquot_initialize(inode);
Al Viroac14a952010-06-06 07:08:19 -0400203 want_delete = 1;
204 }
Christoph Hellwig907f4552010-03-03 09:05:06 -0500205
Mark Fashehfef26652005-09-09 13:01:31 -0700206 truncate_inode_pages(&inode->i_data, 0);
207
Al Viroac14a952010-06-06 07:08:19 -0400208 ext3_discard_reservation(inode);
209 rsv = EXT3_I(inode)->i_block_alloc_info;
210 EXT3_I(inode)->i_block_alloc_info = NULL;
211 if (unlikely(rsv))
212 kfree(rsv);
213
214 if (!want_delete)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700215 goto no_delete;
216
217 handle = start_transaction(inode);
218 if (IS_ERR(handle)) {
Andrew Mortond6859bf2006-03-26 01:38:03 -0800219 /*
220 * If we're going to skip the normal cleanup, we still need to
221 * make sure that the in-core orphan linked list is properly
222 * cleaned up.
223 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700224 ext3_orphan_del(NULL, inode);
225 goto no_delete;
226 }
227
228 if (IS_SYNC(inode))
229 handle->h_sync = 1;
230 inode->i_size = 0;
231 if (inode->i_blocks)
232 ext3_truncate(inode);
233 /*
234 * Kill off the orphan record which ext3_truncate created.
235 * AKPM: I think this can be inside the above `if'.
236 * Note that ext3_orphan_del() has to be able to cope with the
237 * deletion of a non-existent orphan - this is because we don't
238 * know if ext3_truncate() actually created an orphan record.
239 * (Well, we could do this if we need to, but heck - it works)
240 */
241 ext3_orphan_del(handle, inode);
242 EXT3_I(inode)->i_dtime = get_seconds();
243
Mingming Caoae6ddcc2006-09-27 01:49:27 -0700244 /*
Linus Torvalds1da177e2005-04-16 15:20:36 -0700245 * One subtle ordering requirement: if anything has gone wrong
246 * (transaction abort, IO errors, whatever), then we can still
247 * do these next steps (the fs will already have been marked as
248 * having errors), but we can't free the inode if the mark_dirty
Mingming Caoae6ddcc2006-09-27 01:49:27 -0700249 * fails.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700250 */
Al Viroac14a952010-06-06 07:08:19 -0400251 if (ext3_mark_inode_dirty(handle, inode)) {
252 /* If that failed, just dquot_drop() and be done with that */
253 dquot_drop(inode);
254 end_writeback(inode);
255 } else {
256 ext3_xattr_delete_inode(handle, inode);
257 dquot_free_inode(inode);
258 dquot_drop(inode);
259 end_writeback(inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700260 ext3_free_inode(handle, inode);
Al Viroac14a952010-06-06 07:08:19 -0400261 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700262 ext3_journal_stop(handle);
263 return;
264no_delete:
Al Viroac14a952010-06-06 07:08:19 -0400265 end_writeback(inode);
266 dquot_drop(inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700267}
268
Linus Torvalds1da177e2005-04-16 15:20:36 -0700269typedef struct {
270 __le32 *p;
271 __le32 key;
272 struct buffer_head *bh;
273} Indirect;
274
275static inline void add_chain(Indirect *p, struct buffer_head *bh, __le32 *v)
276{
277 p->key = *(p->p = v);
278 p->bh = bh;
279}
280
Andrew Mortond6859bf2006-03-26 01:38:03 -0800281static int verify_chain(Indirect *from, Indirect *to)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700282{
283 while (from <= to && from->key == *from->p)
284 from++;
285 return (from > to);
286}
287
288/**
289 * ext3_block_to_path - parse the block number into array of offsets
290 * @inode: inode in question (we are only interested in its superblock)
291 * @i_block: block number to be parsed
292 * @offsets: array to store the offsets in
293 * @boundary: set this non-zero if the referred-to block is likely to be
294 * followed (on disk) by an indirect block.
295 *
296 * To store the locations of file's data ext3 uses a data structure common
297 * for UNIX filesystems - tree of pointers anchored in the inode, with
298 * data blocks at leaves and indirect blocks in intermediate nodes.
299 * This function translates the block number into path in that tree -
300 * return value is the path length and @offsets[n] is the offset of
301 * pointer to (n+1)th node in the nth one. If @block is out of range
302 * (negative or too large) warning is printed and zero returned.
303 *
304 * Note: function doesn't find node addresses, so no IO is needed. All
305 * we need to know is the capacity of indirect blocks (taken from the
306 * inode->i_sb).
307 */
308
309/*
310 * Portability note: the last comparison (check that we fit into triple
311 * indirect block) is spelled differently, because otherwise on an
312 * architecture with 32-bit longs and 8Kb pages we might get into trouble
313 * if our filesystem had 8Kb blocks. We might use long long, but that would
314 * kill us on x86. Oh, well, at least the sign propagation does not matter -
315 * i_block would have to be negative in the very beginning, so we would not
316 * get there at all.
317 */
318
319static int ext3_block_to_path(struct inode *inode,
320 long i_block, int offsets[4], int *boundary)
321{
322 int ptrs = EXT3_ADDR_PER_BLOCK(inode->i_sb);
323 int ptrs_bits = EXT3_ADDR_PER_BLOCK_BITS(inode->i_sb);
324 const long direct_blocks = EXT3_NDIR_BLOCKS,
325 indirect_blocks = ptrs,
326 double_blocks = (1 << (ptrs_bits * 2));
327 int n = 0;
328 int final = 0;
329
330 if (i_block < 0) {
331 ext3_warning (inode->i_sb, "ext3_block_to_path", "block < 0");
332 } else if (i_block < direct_blocks) {
333 offsets[n++] = i_block;
334 final = direct_blocks;
335 } else if ( (i_block -= direct_blocks) < indirect_blocks) {
336 offsets[n++] = EXT3_IND_BLOCK;
337 offsets[n++] = i_block;
338 final = ptrs;
339 } else if ((i_block -= indirect_blocks) < double_blocks) {
340 offsets[n++] = EXT3_DIND_BLOCK;
341 offsets[n++] = i_block >> ptrs_bits;
342 offsets[n++] = i_block & (ptrs - 1);
343 final = ptrs;
344 } else if (((i_block -= double_blocks) >> (ptrs_bits * 2)) < ptrs) {
345 offsets[n++] = EXT3_TIND_BLOCK;
346 offsets[n++] = i_block >> (ptrs_bits * 2);
347 offsets[n++] = (i_block >> ptrs_bits) & (ptrs - 1);
348 offsets[n++] = i_block & (ptrs - 1);
349 final = ptrs;
350 } else {
Andrew Mortond6859bf2006-03-26 01:38:03 -0800351 ext3_warning(inode->i_sb, "ext3_block_to_path", "block > big");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700352 }
353 if (boundary)
Mingming Cao89747d32006-03-26 01:37:55 -0800354 *boundary = final - 1 - (i_block & (ptrs - 1));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700355 return n;
356}
357
358/**
359 * ext3_get_branch - read the chain of indirect blocks leading to data
360 * @inode: inode in question
361 * @depth: depth of the chain (1 - direct pointer, etc.)
362 * @offsets: offsets of pointers in inode/indirect blocks
363 * @chain: place to store the result
364 * @err: here we store the error value
365 *
366 * Function fills the array of triples <key, p, bh> and returns %NULL
367 * if everything went OK or the pointer to the last filled triple
368 * (incomplete one) otherwise. Upon the return chain[i].key contains
369 * the number of (i+1)-th block in the chain (as it is stored in memory,
370 * i.e. little-endian 32-bit), chain[i].p contains the address of that
371 * number (it points into struct inode for i==0 and into the bh->b_data
372 * for i>0) and chain[i].bh points to the buffer_head of i-th indirect
373 * block for i>0 and NULL for i==0. In other words, it holds the block
374 * numbers of the chain, addresses they were taken from (and where we can
375 * verify that chain did not change) and buffer_heads hosting these
376 * numbers.
377 *
378 * Function stops when it stumbles upon zero pointer (absent block)
379 * (pointer to last triple returned, *@err == 0)
380 * or when it gets an IO error reading an indirect block
381 * (ditto, *@err == -EIO)
382 * or when it notices that chain had been changed while it was reading
383 * (ditto, *@err == -EAGAIN)
384 * or when it reads all @depth-1 indirect blocks successfully and finds
385 * the whole chain, all way to the data (returns %NULL, *err == 0).
386 */
387static Indirect *ext3_get_branch(struct inode *inode, int depth, int *offsets,
388 Indirect chain[4], int *err)
389{
390 struct super_block *sb = inode->i_sb;
391 Indirect *p = chain;
392 struct buffer_head *bh;
393
394 *err = 0;
395 /* i_data is not going away, no lock needed */
396 add_chain (chain, NULL, EXT3_I(inode)->i_data + *offsets);
397 if (!p->key)
398 goto no_block;
399 while (--depth) {
400 bh = sb_bread(sb, le32_to_cpu(p->key));
401 if (!bh)
402 goto failure;
403 /* Reader: pointers */
404 if (!verify_chain(chain, p))
405 goto changed;
406 add_chain(++p, bh, (__le32*)bh->b_data + *++offsets);
407 /* Reader: end */
408 if (!p->key)
409 goto no_block;
410 }
411 return NULL;
412
413changed:
414 brelse(bh);
415 *err = -EAGAIN;
416 goto no_block;
417failure:
418 *err = -EIO;
419no_block:
420 return p;
421}
422
423/**
424 * ext3_find_near - find a place for allocation with sufficient locality
425 * @inode: owner
426 * @ind: descriptor of indirect block.
427 *
Benoit Boissinot1cc8dcf2008-04-21 22:45:55 +0000428 * This function returns the preferred place for block allocation.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700429 * It is used when heuristic for sequential allocation fails.
430 * Rules are:
431 * + if there is a block to the left of our position - allocate near it.
432 * + if pointer will live in indirect block - allocate near that block.
433 * + if pointer will live in inode - allocate in the same
Mingming Caoae6ddcc2006-09-27 01:49:27 -0700434 * cylinder group.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700435 *
436 * In the latter case we colour the starting block by the callers PID to
437 * prevent it from clashing with concurrent allocations for a different inode
438 * in the same block group. The PID is used here so that functionally related
439 * files will be close-by on-disk.
440 *
441 * Caller must make sure that @ind is valid and will stay that way.
442 */
Mingming Cao43d23f92006-06-25 05:48:07 -0700443static ext3_fsblk_t ext3_find_near(struct inode *inode, Indirect *ind)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700444{
445 struct ext3_inode_info *ei = EXT3_I(inode);
446 __le32 *start = ind->bh ? (__le32*) ind->bh->b_data : ei->i_data;
447 __le32 *p;
Mingming Cao43d23f92006-06-25 05:48:07 -0700448 ext3_fsblk_t bg_start;
449 ext3_grpblk_t colour;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700450
451 /* Try to find previous block */
Andrew Mortond6859bf2006-03-26 01:38:03 -0800452 for (p = ind->p - 1; p >= start; p--) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700453 if (*p)
454 return le32_to_cpu(*p);
Andrew Mortond6859bf2006-03-26 01:38:03 -0800455 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700456
457 /* No such thing, so let's try location of indirect block */
458 if (ind->bh)
459 return ind->bh->b_blocknr;
460
461 /*
Andrew Mortond6859bf2006-03-26 01:38:03 -0800462 * It is going to be referred to from the inode itself? OK, just put it
463 * into the same cylinder group then.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700464 */
Mingming Cao43d23f92006-06-25 05:48:07 -0700465 bg_start = ext3_group_first_block_no(inode->i_sb, ei->i_block_group);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700466 colour = (current->pid % 16) *
467 (EXT3_BLOCKS_PER_GROUP(inode->i_sb) / 16);
468 return bg_start + colour;
469}
470
471/**
Benoit Boissinot1cc8dcf2008-04-21 22:45:55 +0000472 * ext3_find_goal - find a preferred place for allocation.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700473 * @inode: owner
474 * @block: block we want
Linus Torvalds1da177e2005-04-16 15:20:36 -0700475 * @partial: pointer to the last triple within a chain
Linus Torvalds1da177e2005-04-16 15:20:36 -0700476 *
Benoit Boissinot1cc8dcf2008-04-21 22:45:55 +0000477 * Normally this function find the preferred place for block allocation,
Akinobu Mitafb01bfd2008-02-06 01:40:16 -0800478 * returns it.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700479 */
480
Mingming Cao43d23f92006-06-25 05:48:07 -0700481static ext3_fsblk_t ext3_find_goal(struct inode *inode, long block,
Akinobu Mitafb01bfd2008-02-06 01:40:16 -0800482 Indirect *partial)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700483{
Andrew Mortond6859bf2006-03-26 01:38:03 -0800484 struct ext3_block_alloc_info *block_i;
485
486 block_i = EXT3_I(inode)->i_block_alloc_info;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700487
488 /*
489 * try the heuristic for sequential allocation,
490 * failing that at least try to get decent locality.
491 */
492 if (block_i && (block == block_i->last_alloc_logical_block + 1)
493 && (block_i->last_alloc_physical_block != 0)) {
Mingming Caofe55c452005-05-01 08:59:20 -0700494 return block_i->last_alloc_physical_block + 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700495 }
496
Mingming Caofe55c452005-05-01 08:59:20 -0700497 return ext3_find_near(inode, partial);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700498}
Andrew Mortond6859bf2006-03-26 01:38:03 -0800499
Mingming Caob47b2472006-03-26 01:37:56 -0800500/**
Namhyung Kima4c18ad2010-10-19 00:34:35 +0900501 * ext3_blks_to_allocate - Look up the block map and count the number
Mingming Caob47b2472006-03-26 01:37:56 -0800502 * of direct blocks need to be allocated for the given branch.
503 *
Dave Kleikampe9ad5622006-09-27 01:49:35 -0700504 * @branch: chain of indirect blocks
Mingming Caob47b2472006-03-26 01:37:56 -0800505 * @k: number of blocks need for indirect blocks
506 * @blks: number of data blocks to be mapped.
507 * @blocks_to_boundary: the offset in the indirect block
508 *
509 * return the total number of blocks to be allocate, including the
510 * direct and indirect blocks.
511 */
Andrew Mortond6859bf2006-03-26 01:38:03 -0800512static int ext3_blks_to_allocate(Indirect *branch, int k, unsigned long blks,
Mingming Caob47b2472006-03-26 01:37:56 -0800513 int blocks_to_boundary)
514{
515 unsigned long count = 0;
516
517 /*
518 * Simple case, [t,d]Indirect block(s) has not allocated yet
519 * then it's clear blocks on that path have not allocated
520 */
521 if (k > 0) {
Andrew Mortond6859bf2006-03-26 01:38:03 -0800522 /* right now we don't handle cross boundary allocation */
Mingming Caob47b2472006-03-26 01:37:56 -0800523 if (blks < blocks_to_boundary + 1)
524 count += blks;
525 else
526 count += blocks_to_boundary + 1;
527 return count;
528 }
529
530 count++;
531 while (count < blks && count <= blocks_to_boundary &&
532 le32_to_cpu(*(branch[0].p + count)) == 0) {
533 count++;
534 }
535 return count;
536}
537
538/**
Namhyung Kima4c18ad2010-10-19 00:34:35 +0900539 * ext3_alloc_blocks - multiple allocate blocks needed for a branch
540 * @handle: handle for this transaction
541 * @inode: owner
542 * @goal: preferred place for allocation
Mingming Caob47b2472006-03-26 01:37:56 -0800543 * @indirect_blks: the number of blocks need to allocate for indirect
544 * blocks
Namhyung Kima4c18ad2010-10-19 00:34:35 +0900545 * @blks: number of blocks need to allocated for direct blocks
Mingming Caob47b2472006-03-26 01:37:56 -0800546 * @new_blocks: on return it will store the new block numbers for
547 * the indirect blocks(if needed) and the first direct block,
Namhyung Kima4c18ad2010-10-19 00:34:35 +0900548 * @err: here we store the error value
549 *
550 * return the number of direct blocks allocated
Mingming Caob47b2472006-03-26 01:37:56 -0800551 */
552static int ext3_alloc_blocks(handle_t *handle, struct inode *inode,
Mingming Cao43d23f92006-06-25 05:48:07 -0700553 ext3_fsblk_t goal, int indirect_blks, int blks,
554 ext3_fsblk_t new_blocks[4], int *err)
Mingming Caob47b2472006-03-26 01:37:56 -0800555{
556 int target, i;
557 unsigned long count = 0;
558 int index = 0;
Mingming Cao43d23f92006-06-25 05:48:07 -0700559 ext3_fsblk_t current_block = 0;
Mingming Caob47b2472006-03-26 01:37:56 -0800560 int ret = 0;
561
562 /*
563 * Here we try to allocate the requested multiple blocks at once,
564 * on a best-effort basis.
565 * To build a branch, we should allocate blocks for
566 * the indirect blocks(if not allocated yet), and at least
567 * the first direct block of this branch. That's the
568 * minimum number of blocks need to allocate(required)
569 */
570 target = blks + indirect_blks;
571
572 while (1) {
573 count = target;
574 /* allocating blocks for indirect blocks and direct blocks */
Andrew Mortond6859bf2006-03-26 01:38:03 -0800575 current_block = ext3_new_blocks(handle,inode,goal,&count,err);
Mingming Caob47b2472006-03-26 01:37:56 -0800576 if (*err)
577 goto failed_out;
578
579 target -= count;
580 /* allocate blocks for indirect blocks */
581 while (index < indirect_blks && count) {
582 new_blocks[index++] = current_block++;
583 count--;
584 }
585
586 if (count > 0)
587 break;
588 }
589
590 /* save the new block number for the first direct block */
591 new_blocks[index] = current_block;
592
593 /* total number of blocks allocated for direct blocks */
594 ret = count;
595 *err = 0;
596 return ret;
597failed_out:
598 for (i = 0; i <index; i++)
599 ext3_free_blocks(handle, inode, new_blocks[i], 1);
600 return ret;
601}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700602
603/**
604 * ext3_alloc_branch - allocate and set up a chain of blocks.
Namhyung Kima4c18ad2010-10-19 00:34:35 +0900605 * @handle: handle for this transaction
Linus Torvalds1da177e2005-04-16 15:20:36 -0700606 * @inode: owner
Mingming Caob47b2472006-03-26 01:37:56 -0800607 * @indirect_blks: number of allocated indirect blocks
608 * @blks: number of allocated direct blocks
Namhyung Kima4c18ad2010-10-19 00:34:35 +0900609 * @goal: preferred place for allocation
Linus Torvalds1da177e2005-04-16 15:20:36 -0700610 * @offsets: offsets (in the blocks) to store the pointers to next.
611 * @branch: place to store the chain in.
612 *
Mingming Caob47b2472006-03-26 01:37:56 -0800613 * This function allocates blocks, zeroes out all but the last one,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700614 * links them into chain and (if we are synchronous) writes them to disk.
615 * In other words, it prepares a branch that can be spliced onto the
616 * inode. It stores the information about that chain in the branch[], in
617 * the same format as ext3_get_branch() would do. We are calling it after
618 * we had read the existing part of chain and partial points to the last
619 * triple of that (one with zero ->key). Upon the exit we have the same
Glauber de Oliveira Costa5b116872005-10-30 15:02:48 -0800620 * picture as after the successful ext3_get_block(), except that in one
Linus Torvalds1da177e2005-04-16 15:20:36 -0700621 * place chain is disconnected - *branch->p is still zero (we did not
622 * set the last link), but branch->key contains the number that should
623 * be placed into *branch->p to fill that gap.
624 *
625 * If allocation fails we free all blocks we've allocated (and forget
626 * their buffer_heads) and return the error value the from failed
627 * ext3_alloc_block() (normally -ENOSPC). Otherwise we set the chain
628 * as described above and return 0.
629 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700630static int ext3_alloc_branch(handle_t *handle, struct inode *inode,
Mingming Cao43d23f92006-06-25 05:48:07 -0700631 int indirect_blks, int *blks, ext3_fsblk_t goal,
Mingming Caob47b2472006-03-26 01:37:56 -0800632 int *offsets, Indirect *branch)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700633{
634 int blocksize = inode->i_sb->s_blocksize;
Mingming Caob47b2472006-03-26 01:37:56 -0800635 int i, n = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700636 int err = 0;
Mingming Caob47b2472006-03-26 01:37:56 -0800637 struct buffer_head *bh;
638 int num;
Mingming Cao43d23f92006-06-25 05:48:07 -0700639 ext3_fsblk_t new_blocks[4];
640 ext3_fsblk_t current_block;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700641
Mingming Caob47b2472006-03-26 01:37:56 -0800642 num = ext3_alloc_blocks(handle, inode, goal, indirect_blks,
643 *blks, new_blocks, &err);
644 if (err)
645 return err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700646
Mingming Caob47b2472006-03-26 01:37:56 -0800647 branch[0].key = cpu_to_le32(new_blocks[0]);
648 /*
649 * metadata blocks and data blocks are allocated.
650 */
651 for (n = 1; n <= indirect_blks; n++) {
652 /*
653 * Get buffer_head for parent block, zero it out
654 * and set the pointer to new one, then send
655 * parent to disk.
656 */
657 bh = sb_getblk(inode->i_sb, new_blocks[n-1]);
658 branch[n].bh = bh;
659 lock_buffer(bh);
660 BUFFER_TRACE(bh, "call get_create_access");
661 err = ext3_journal_get_create_access(handle, bh);
662 if (err) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700663 unlock_buffer(bh);
Mingming Caob47b2472006-03-26 01:37:56 -0800664 brelse(bh);
665 goto failed;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700666 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700667
Mingming Caob47b2472006-03-26 01:37:56 -0800668 memset(bh->b_data, 0, blocksize);
669 branch[n].p = (__le32 *) bh->b_data + offsets[n];
670 branch[n].key = cpu_to_le32(new_blocks[n]);
671 *branch[n].p = branch[n].key;
672 if ( n == indirect_blks) {
673 current_block = new_blocks[n];
674 /*
675 * End of chain, update the last new metablock of
676 * the chain to point to the new allocated
677 * data blocks numbers
678 */
679 for (i=1; i < num; i++)
680 *(branch[n].p + i) = cpu_to_le32(++current_block);
681 }
682 BUFFER_TRACE(bh, "marking uptodate");
683 set_buffer_uptodate(bh);
684 unlock_buffer(bh);
685
686 BUFFER_TRACE(bh, "call ext3_journal_dirty_metadata");
687 err = ext3_journal_dirty_metadata(handle, bh);
688 if (err)
689 goto failed;
690 }
691 *blks = num;
692 return err;
693failed:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700694 /* Allocation failed, free what we already allocated */
Mingming Caob47b2472006-03-26 01:37:56 -0800695 for (i = 1; i <= n ; i++) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700696 BUFFER_TRACE(branch[i].bh, "call journal_forget");
697 ext3_journal_forget(handle, branch[i].bh);
698 }
Mingming Caob47b2472006-03-26 01:37:56 -0800699 for (i = 0; i <indirect_blks; i++)
700 ext3_free_blocks(handle, inode, new_blocks[i], 1);
701
702 ext3_free_blocks(handle, inode, new_blocks[i], num);
703
Linus Torvalds1da177e2005-04-16 15:20:36 -0700704 return err;
705}
706
707/**
Andrew Mortond6859bf2006-03-26 01:38:03 -0800708 * ext3_splice_branch - splice the allocated branch onto inode.
Namhyung Kima4c18ad2010-10-19 00:34:35 +0900709 * @handle: handle for this transaction
Andrew Mortond6859bf2006-03-26 01:38:03 -0800710 * @inode: owner
711 * @block: (logical) number of block we are adding
Andrew Mortond6859bf2006-03-26 01:38:03 -0800712 * @where: location of missing link
713 * @num: number of indirect blocks we are adding
714 * @blks: number of direct blocks we are adding
Linus Torvalds1da177e2005-04-16 15:20:36 -0700715 *
Andrew Mortond6859bf2006-03-26 01:38:03 -0800716 * This function fills the missing link and does all housekeeping needed in
717 * inode (->i_blocks, etc.). In case of success we end up with the full
718 * chain to new block and return 0.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700719 */
Andrew Mortond6859bf2006-03-26 01:38:03 -0800720static int ext3_splice_branch(handle_t *handle, struct inode *inode,
721 long block, Indirect *where, int num, int blks)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700722{
723 int i;
724 int err = 0;
Andrew Mortond6859bf2006-03-26 01:38:03 -0800725 struct ext3_block_alloc_info *block_i;
Mingming Cao43d23f92006-06-25 05:48:07 -0700726 ext3_fsblk_t current_block;
Jan Karafe8bc912009-10-16 19:26:15 +0200727 struct ext3_inode_info *ei = EXT3_I(inode);
Andrew Mortond6859bf2006-03-26 01:38:03 -0800728
Jan Karafe8bc912009-10-16 19:26:15 +0200729 block_i = ei->i_block_alloc_info;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700730 /*
731 * If we're splicing into a [td]indirect block (as opposed to the
732 * inode) then we need to get write access to the [td]indirect block
733 * before the splice.
734 */
735 if (where->bh) {
736 BUFFER_TRACE(where->bh, "get_write_access");
737 err = ext3_journal_get_write_access(handle, where->bh);
738 if (err)
739 goto err_out;
740 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700741 /* That's it */
742
743 *where->p = where->key;
Andrew Mortond6859bf2006-03-26 01:38:03 -0800744
745 /*
746 * Update the host buffer_head or inode to point to more just allocated
747 * direct blocks blocks
748 */
Mingming Caob47b2472006-03-26 01:37:56 -0800749 if (num == 0 && blks > 1) {
Mingming Cao5dea5172006-05-03 19:55:12 -0700750 current_block = le32_to_cpu(where->key) + 1;
Mingming Caob47b2472006-03-26 01:37:56 -0800751 for (i = 1; i < blks; i++)
752 *(where->p + i ) = cpu_to_le32(current_block++);
753 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700754
755 /*
756 * update the most recently allocated logical & physical block
757 * in i_block_alloc_info, to assist find the proper goal block for next
758 * allocation
759 */
760 if (block_i) {
Mingming Caob47b2472006-03-26 01:37:56 -0800761 block_i->last_alloc_logical_block = block + blks - 1;
Andrew Mortond6859bf2006-03-26 01:38:03 -0800762 block_i->last_alloc_physical_block =
Mingming Cao5dea5172006-05-03 19:55:12 -0700763 le32_to_cpu(where[num].key) + blks - 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700764 }
765
766 /* We are done with atomic stuff, now do the rest of housekeeping */
767
768 inode->i_ctime = CURRENT_TIME_SEC;
769 ext3_mark_inode_dirty(handle, inode);
Jan Karafe8bc912009-10-16 19:26:15 +0200770 /* ext3_mark_inode_dirty already updated i_sync_tid */
771 atomic_set(&ei->i_datasync_tid, handle->h_transaction->t_tid);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700772
773 /* had we spliced it onto indirect block? */
774 if (where->bh) {
775 /*
Andrew Mortond6859bf2006-03-26 01:38:03 -0800776 * If we spliced it onto an indirect block, we haven't
Linus Torvalds1da177e2005-04-16 15:20:36 -0700777 * altered the inode. Note however that if it is being spliced
778 * onto an indirect block at the very end of the file (the
779 * file is growing) then we *will* alter the inode to reflect
780 * the new i_size. But that is not done here - it is done in
781 * generic_commit_write->__mark_inode_dirty->ext3_dirty_inode.
782 */
783 jbd_debug(5, "splicing indirect only\n");
784 BUFFER_TRACE(where->bh, "call ext3_journal_dirty_metadata");
785 err = ext3_journal_dirty_metadata(handle, where->bh);
Mingming Caoae6ddcc2006-09-27 01:49:27 -0700786 if (err)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700787 goto err_out;
788 } else {
789 /*
790 * OK, we spliced it into the inode itself on a direct block.
791 * Inode was dirtied above.
792 */
793 jbd_debug(5, "splicing direct\n");
794 }
795 return err;
796
Linus Torvalds1da177e2005-04-16 15:20:36 -0700797err_out:
Mingming Caob47b2472006-03-26 01:37:56 -0800798 for (i = 1; i <= num; i++) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700799 BUFFER_TRACE(where[i].bh, "call journal_forget");
800 ext3_journal_forget(handle, where[i].bh);
Andrew Mortond6859bf2006-03-26 01:38:03 -0800801 ext3_free_blocks(handle,inode,le32_to_cpu(where[i-1].key),1);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700802 }
Mingming Caob47b2472006-03-26 01:37:56 -0800803 ext3_free_blocks(handle, inode, le32_to_cpu(where[num].key), blks);
804
Linus Torvalds1da177e2005-04-16 15:20:36 -0700805 return err;
806}
807
808/*
809 * Allocation strategy is simple: if we have to allocate something, we will
810 * have to go the whole way to leaf. So let's do it before attaching anything
811 * to tree, set linkage between the newborn blocks, write them if sync is
812 * required, recheck the path, free and repeat if check fails, otherwise
813 * set the last missing link (that will protect us from any truncate-generated
814 * removals - all blocks on the path are immune now) and possibly force the
815 * write on the parent block.
816 * That has a nice additional property: no special recovery from the failed
817 * allocations is needed - we simply release blocks and do not touch anything
818 * reachable from inode.
819 *
Andrew Mortond6859bf2006-03-26 01:38:03 -0800820 * `handle' can be NULL if create == 0.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700821 *
822 * The BKL may not be held on entry here. Be sure to take it early.
Mingming Cao89747d32006-03-26 01:37:55 -0800823 * return > 0, # of blocks mapped or allocated.
824 * return = 0, if plain lookup failed.
825 * return < 0, error case.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700826 */
Andrew Mortond6859bf2006-03-26 01:38:03 -0800827int ext3_get_blocks_handle(handle_t *handle, struct inode *inode,
828 sector_t iblock, unsigned long maxblocks,
829 struct buffer_head *bh_result,
Jan Kara43237b52009-05-20 18:41:58 +0200830 int create)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700831{
832 int err = -EIO;
833 int offsets[4];
834 Indirect chain[4];
835 Indirect *partial;
Mingming Cao43d23f92006-06-25 05:48:07 -0700836 ext3_fsblk_t goal;
Mingming Caob47b2472006-03-26 01:37:56 -0800837 int indirect_blks;
Mingming Cao89747d32006-03-26 01:37:55 -0800838 int blocks_to_boundary = 0;
839 int depth;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700840 struct ext3_inode_info *ei = EXT3_I(inode);
Mingming Cao89747d32006-03-26 01:37:55 -0800841 int count = 0;
Mingming Cao43d23f92006-06-25 05:48:07 -0700842 ext3_fsblk_t first_block = 0;
Mingming Cao89747d32006-03-26 01:37:55 -0800843
Linus Torvalds1da177e2005-04-16 15:20:36 -0700844
845 J_ASSERT(handle != NULL || create == 0);
Andrew Mortond6859bf2006-03-26 01:38:03 -0800846 depth = ext3_block_to_path(inode,iblock,offsets,&blocks_to_boundary);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700847
848 if (depth == 0)
849 goto out;
850
Linus Torvalds1da177e2005-04-16 15:20:36 -0700851 partial = ext3_get_branch(inode, depth, offsets, chain, &err);
852
853 /* Simplest case - block found, no allocation needed */
854 if (!partial) {
Mingming Cao5dea5172006-05-03 19:55:12 -0700855 first_block = le32_to_cpu(chain[depth - 1].key);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700856 clear_buffer_new(bh_result);
Mingming Cao89747d32006-03-26 01:37:55 -0800857 count++;
858 /*map more blocks*/
859 while (count < maxblocks && count <= blocks_to_boundary) {
Mingming Cao43d23f92006-06-25 05:48:07 -0700860 ext3_fsblk_t blk;
Mingming Cao5dea5172006-05-03 19:55:12 -0700861
Jan Karae8ef7aa2009-06-17 16:26:23 -0700862 if (!verify_chain(chain, chain + depth - 1)) {
Mingming Cao89747d32006-03-26 01:37:55 -0800863 /*
864 * Indirect block might be removed by
865 * truncate while we were reading it.
866 * Handling of that case: forget what we've
867 * got now. Flag the err as EAGAIN, so it
868 * will reread.
869 */
870 err = -EAGAIN;
871 count = 0;
872 break;
873 }
Mingming Cao5dea5172006-05-03 19:55:12 -0700874 blk = le32_to_cpu(*(chain[depth-1].p + count));
875
876 if (blk == first_block + count)
Mingming Cao89747d32006-03-26 01:37:55 -0800877 count++;
878 else
879 break;
880 }
881 if (err != -EAGAIN)
882 goto got_it;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700883 }
884
885 /* Next simple case - plain lookup or failed read of indirect block */
Mingming Caofe55c452005-05-01 08:59:20 -0700886 if (!create || err == -EIO)
887 goto cleanup;
888
Arjan van de Ven97461512006-03-23 03:00:42 -0800889 mutex_lock(&ei->truncate_mutex);
Mingming Caofe55c452005-05-01 08:59:20 -0700890
891 /*
892 * If the indirect block is missing while we are reading
893 * the chain(ext3_get_branch() returns -EAGAIN err), or
894 * if the chain has been changed after we grab the semaphore,
895 * (either because another process truncated this branch, or
896 * another get_block allocated this branch) re-grab the chain to see if
897 * the request block has been allocated or not.
898 *
899 * Since we already block the truncate/other get_block
900 * at this point, we will have the current copy of the chain when we
901 * splice the branch into the tree.
902 */
903 if (err == -EAGAIN || !verify_chain(chain, partial)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700904 while (partial > chain) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700905 brelse(partial->bh);
906 partial--;
907 }
Mingming Caofe55c452005-05-01 08:59:20 -0700908 partial = ext3_get_branch(inode, depth, offsets, chain, &err);
909 if (!partial) {
Mingming Cao89747d32006-03-26 01:37:55 -0800910 count++;
Arjan van de Ven97461512006-03-23 03:00:42 -0800911 mutex_unlock(&ei->truncate_mutex);
Mingming Caofe55c452005-05-01 08:59:20 -0700912 if (err)
913 goto cleanup;
914 clear_buffer_new(bh_result);
915 goto got_it;
916 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700917 }
918
919 /*
Mingming Caofe55c452005-05-01 08:59:20 -0700920 * Okay, we need to do block allocation. Lazily initialize the block
921 * allocation info here if necessary
922 */
923 if (S_ISREG(inode->i_mode) && (!ei->i_block_alloc_info))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700924 ext3_init_block_alloc_info(inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700925
Akinobu Mitafb01bfd2008-02-06 01:40:16 -0800926 goal = ext3_find_goal(inode, iblock, partial);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700927
Mingming Caob47b2472006-03-26 01:37:56 -0800928 /* the number of blocks need to allocate for [d,t]indirect blocks */
929 indirect_blks = (chain + depth) - partial - 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700930
931 /*
Mingming Caob47b2472006-03-26 01:37:56 -0800932 * Next look up the indirect map to count the totoal number of
933 * direct blocks to allocate for this branch.
934 */
935 count = ext3_blks_to_allocate(partial, indirect_blks,
936 maxblocks, blocks_to_boundary);
937 /*
Linus Torvalds1da177e2005-04-16 15:20:36 -0700938 * Block out ext3_truncate while we alter the tree
939 */
Mingming Caob47b2472006-03-26 01:37:56 -0800940 err = ext3_alloc_branch(handle, inode, indirect_blks, &count, goal,
Mingming Caofe55c452005-05-01 08:59:20 -0700941 offsets + (partial - chain), partial);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700942
Mingming Caofe55c452005-05-01 08:59:20 -0700943 /*
944 * The ext3_splice_branch call will free and forget any buffers
Linus Torvalds1da177e2005-04-16 15:20:36 -0700945 * on the new chain if there is a failure, but that risks using
946 * up transaction credits, especially for bitmaps where the
947 * credits cannot be returned. Can we handle this somehow? We
Mingming Caofe55c452005-05-01 08:59:20 -0700948 * may need to return -EAGAIN upwards in the worst case. --sct
949 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700950 if (!err)
Mingming Caob47b2472006-03-26 01:37:56 -0800951 err = ext3_splice_branch(handle, inode, iblock,
952 partial, indirect_blks, count);
Arjan van de Ven97461512006-03-23 03:00:42 -0800953 mutex_unlock(&ei->truncate_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700954 if (err)
955 goto cleanup;
956
957 set_buffer_new(bh_result);
Mingming Caofe55c452005-05-01 08:59:20 -0700958got_it:
959 map_bh(bh_result, inode->i_sb, le32_to_cpu(chain[depth-1].key));
Suparna Bhattacharya20acaa12006-09-16 12:15:58 -0700960 if (count > blocks_to_boundary)
Mingming Caofe55c452005-05-01 08:59:20 -0700961 set_buffer_boundary(bh_result);
Mingming Cao89747d32006-03-26 01:37:55 -0800962 err = count;
Mingming Caofe55c452005-05-01 08:59:20 -0700963 /* Clean up and exit */
964 partial = chain + depth - 1; /* the whole chain */
965cleanup:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700966 while (partial > chain) {
Mingming Caofe55c452005-05-01 08:59:20 -0700967 BUFFER_TRACE(partial->bh, "call brelse");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700968 brelse(partial->bh);
969 partial--;
970 }
Mingming Caofe55c452005-05-01 08:59:20 -0700971 BUFFER_TRACE(bh_result, "returned");
972out:
973 return err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700974}
975
Jan Karabd1939d2008-02-06 01:40:21 -0800976/* Maximum number of blocks we map for direct IO at once. */
977#define DIO_MAX_BLOCKS 4096
978/*
979 * Number of credits we need for writing DIO_MAX_BLOCKS:
980 * We need sb + group descriptor + bitmap + inode -> 4
981 * For B blocks with A block pointers per block we need:
982 * 1 (triple ind.) + (B/A/A + 2) (doubly ind.) + (B/A + 2) (indirect).
983 * If we plug in 4096 for B and 256 for A (for 1KB block size), we get 25.
984 */
985#define DIO_CREDITS 25
Linus Torvalds1da177e2005-04-16 15:20:36 -0700986
Badari Pulavartyf91a2ad2006-03-26 01:38:04 -0800987static int ext3_get_block(struct inode *inode, sector_t iblock,
988 struct buffer_head *bh_result, int create)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700989{
Dmitriy Monakhov3e4fdaf2007-02-10 01:46:35 -0800990 handle_t *handle = ext3_journal_current_handle();
Jan Karabd1939d2008-02-06 01:40:21 -0800991 int ret = 0, started = 0;
Badari Pulavarty1d8fa7a2006-03-26 01:38:02 -0800992 unsigned max_blocks = bh_result->b_size >> inode->i_blkbits;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700993
Jan Karabd1939d2008-02-06 01:40:21 -0800994 if (create && !handle) { /* Direct IO write... */
995 if (max_blocks > DIO_MAX_BLOCKS)
996 max_blocks = DIO_MAX_BLOCKS;
997 handle = ext3_journal_start(inode, DIO_CREDITS +
Dmitry Monakhovc4590012009-12-09 03:05:30 +0300998 EXT3_MAXQUOTAS_TRANS_BLOCKS(inode->i_sb));
Jan Karabd1939d2008-02-06 01:40:21 -0800999 if (IS_ERR(handle)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001000 ret = PTR_ERR(handle);
Jan Karabd1939d2008-02-06 01:40:21 -08001001 goto out;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001002 }
Jan Karabd1939d2008-02-06 01:40:21 -08001003 started = 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001004 }
1005
Jan Karabd1939d2008-02-06 01:40:21 -08001006 ret = ext3_get_blocks_handle(handle, inode, iblock,
Jan Kara43237b52009-05-20 18:41:58 +02001007 max_blocks, bh_result, create);
Jan Karabd1939d2008-02-06 01:40:21 -08001008 if (ret > 0) {
1009 bh_result->b_size = (ret << inode->i_blkbits);
1010 ret = 0;
Mingming Cao89747d32006-03-26 01:37:55 -08001011 }
Jan Karabd1939d2008-02-06 01:40:21 -08001012 if (started)
1013 ext3_journal_stop(handle);
1014out:
Linus Torvalds1da177e2005-04-16 15:20:36 -07001015 return ret;
1016}
1017
Josef Bacik68c9d702008-10-03 17:32:43 -04001018int ext3_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
1019 u64 start, u64 len)
1020{
1021 return generic_block_fiemap(inode, fieinfo, start, len,
1022 ext3_get_block);
1023}
1024
Linus Torvalds1da177e2005-04-16 15:20:36 -07001025/*
1026 * `handle' can be NULL if create is zero
1027 */
Andrew Mortond6859bf2006-03-26 01:38:03 -08001028struct buffer_head *ext3_getblk(handle_t *handle, struct inode *inode,
1029 long block, int create, int *errp)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001030{
1031 struct buffer_head dummy;
1032 int fatal = 0, err;
1033
1034 J_ASSERT(handle != NULL || create == 0);
1035
1036 dummy.b_state = 0;
1037 dummy.b_blocknr = -1000;
1038 buffer_trace_init(&dummy.b_history);
Mingming Cao89747d32006-03-26 01:37:55 -08001039 err = ext3_get_blocks_handle(handle, inode, block, 1,
Jan Kara43237b52009-05-20 18:41:58 +02001040 &dummy, create);
Badari Pulavarty3665d0e2006-09-08 09:48:21 -07001041 /*
1042 * ext3_get_blocks_handle() returns number of blocks
1043 * mapped. 0 in case of a HOLE.
1044 */
1045 if (err > 0) {
1046 if (err > 1)
1047 WARN_ON(1);
Mingming Cao89747d32006-03-26 01:37:55 -08001048 err = 0;
Mingming Cao89747d32006-03-26 01:37:55 -08001049 }
1050 *errp = err;
1051 if (!err && buffer_mapped(&dummy)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001052 struct buffer_head *bh;
1053 bh = sb_getblk(inode->i_sb, dummy.b_blocknr);
Glauber de Oliveira Costa2973dfd2005-10-30 15:03:05 -08001054 if (!bh) {
1055 *errp = -EIO;
1056 goto err;
1057 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001058 if (buffer_new(&dummy)) {
1059 J_ASSERT(create != 0);
Stephen Hemmingerc80544d2007-10-18 03:07:05 -07001060 J_ASSERT(handle != NULL);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001061
Andrew Mortond6859bf2006-03-26 01:38:03 -08001062 /*
1063 * Now that we do not always journal data, we should
1064 * keep in mind whether this should always journal the
1065 * new buffer as metadata. For now, regular file
1066 * writes use ext3_get_block instead, so it's not a
1067 * problem.
1068 */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001069 lock_buffer(bh);
1070 BUFFER_TRACE(bh, "call get_create_access");
1071 fatal = ext3_journal_get_create_access(handle, bh);
1072 if (!fatal && !buffer_uptodate(bh)) {
Andrew Mortond6859bf2006-03-26 01:38:03 -08001073 memset(bh->b_data,0,inode->i_sb->s_blocksize);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001074 set_buffer_uptodate(bh);
1075 }
1076 unlock_buffer(bh);
1077 BUFFER_TRACE(bh, "call ext3_journal_dirty_metadata");
1078 err = ext3_journal_dirty_metadata(handle, bh);
1079 if (!fatal)
1080 fatal = err;
1081 } else {
1082 BUFFER_TRACE(bh, "not a new buffer");
1083 }
1084 if (fatal) {
1085 *errp = fatal;
1086 brelse(bh);
1087 bh = NULL;
1088 }
1089 return bh;
1090 }
Glauber de Oliveira Costa2973dfd2005-10-30 15:03:05 -08001091err:
Linus Torvalds1da177e2005-04-16 15:20:36 -07001092 return NULL;
1093}
1094
Andrew Mortond6859bf2006-03-26 01:38:03 -08001095struct buffer_head *ext3_bread(handle_t *handle, struct inode *inode,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001096 int block, int create, int *err)
1097{
1098 struct buffer_head * bh;
1099
1100 bh = ext3_getblk(handle, inode, block, create, err);
1101 if (!bh)
1102 return bh;
1103 if (buffer_uptodate(bh))
1104 return bh;
Jens Axboecaa38fb2006-07-23 01:41:26 +02001105 ll_rw_block(READ_META, 1, &bh);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001106 wait_on_buffer(bh);
1107 if (buffer_uptodate(bh))
1108 return bh;
1109 put_bh(bh);
1110 *err = -EIO;
1111 return NULL;
1112}
1113
1114static int walk_page_buffers( handle_t *handle,
1115 struct buffer_head *head,
1116 unsigned from,
1117 unsigned to,
1118 int *partial,
1119 int (*fn)( handle_t *handle,
1120 struct buffer_head *bh))
1121{
1122 struct buffer_head *bh;
1123 unsigned block_start, block_end;
1124 unsigned blocksize = head->b_size;
1125 int err, ret = 0;
1126 struct buffer_head *next;
1127
1128 for ( bh = head, block_start = 0;
1129 ret == 0 && (bh != head || !block_start);
Dave Kleikampe9ad5622006-09-27 01:49:35 -07001130 block_start = block_end, bh = next)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001131 {
1132 next = bh->b_this_page;
1133 block_end = block_start + blocksize;
1134 if (block_end <= from || block_start >= to) {
1135 if (partial && !buffer_uptodate(bh))
1136 *partial = 1;
1137 continue;
1138 }
1139 err = (*fn)(handle, bh);
1140 if (!ret)
1141 ret = err;
1142 }
1143 return ret;
1144}
1145
1146/*
1147 * To preserve ordering, it is essential that the hole instantiation and
1148 * the data write be encapsulated in a single transaction. We cannot
1149 * close off a transaction and start a new one between the ext3_get_block()
1150 * and the commit_write(). So doing the journal_start at the start of
1151 * prepare_write() is the right place.
1152 *
1153 * Also, this function can nest inside ext3_writepage() ->
1154 * block_write_full_page(). In that case, we *know* that ext3_writepage()
1155 * has generated enough buffer credits to do the whole page. So we won't
1156 * block on the journal in that case, which is good, because the caller may
1157 * be PF_MEMALLOC.
1158 *
1159 * By accident, ext3 can be reentered when a transaction is open via
1160 * quota file writes. If we were to commit the transaction while thus
1161 * reentered, there can be a deadlock - we would be holding a quota
1162 * lock, and the commit would never complete if another thread had a
1163 * transaction open and was blocking on the quota lock - a ranking
1164 * violation.
1165 *
1166 * So what we do is to rely on the fact that journal_stop/journal_start
1167 * will _not_ run commit under these circumstances because handle->h_ref
1168 * is elevated. We'll still have enough credits for the tiny quotafile
Mingming Caoae6ddcc2006-09-27 01:49:27 -07001169 * write.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001170 */
Andrew Mortond6859bf2006-03-26 01:38:03 -08001171static int do_journal_get_write_access(handle_t *handle,
1172 struct buffer_head *bh)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001173{
Jan Kara5f11e6a2010-08-05 12:38:26 +02001174 int dirty = buffer_dirty(bh);
1175 int ret;
1176
Linus Torvalds1da177e2005-04-16 15:20:36 -07001177 if (!buffer_mapped(bh) || buffer_freed(bh))
1178 return 0;
Jan Kara5f11e6a2010-08-05 12:38:26 +02001179 /*
1180 * __block_prepare_write() could have dirtied some buffers. Clean
1181 * the dirty bit as jbd2_journal_get_write_access() could complain
1182 * otherwise about fs integrity issues. Setting of the dirty bit
1183 * by __block_prepare_write() isn't a real problem here as we clear
1184 * the bit before releasing a page lock and thus writeback cannot
1185 * ever write the buffer.
1186 */
1187 if (dirty)
1188 clear_buffer_dirty(bh);
1189 ret = ext3_journal_get_write_access(handle, bh);
1190 if (!ret && dirty)
1191 ret = ext3_journal_dirty_metadata(handle, bh);
1192 return ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001193}
1194
Jan Kara68eb3db2009-12-01 16:53:06 +01001195/*
1196 * Truncate blocks that were not used by write. We have to truncate the
1197 * pagecache as well so that corresponding buffers get properly unmapped.
1198 */
1199static void ext3_truncate_failed_write(struct inode *inode)
1200{
1201 truncate_inode_pages(inode->i_mapping, inode->i_size);
1202 ext3_truncate(inode);
1203}
1204
Nick Pigginf4fc66a2007-10-16 01:25:05 -07001205static int ext3_write_begin(struct file *file, struct address_space *mapping,
1206 loff_t pos, unsigned len, unsigned flags,
1207 struct page **pagep, void **fsdata)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001208{
Nick Pigginf4fc66a2007-10-16 01:25:05 -07001209 struct inode *inode = mapping->host;
Jan Kara695f6ae2009-04-02 16:57:17 -07001210 int ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001211 handle_t *handle;
1212 int retries = 0;
Nick Pigginf4fc66a2007-10-16 01:25:05 -07001213 struct page *page;
1214 pgoff_t index;
1215 unsigned from, to;
Jan Kara695f6ae2009-04-02 16:57:17 -07001216 /* Reserve one block more for addition to orphan list in case
1217 * we allocate blocks but write fails for some reason */
1218 int needed_blocks = ext3_writepage_trans_blocks(inode) + 1;
Nick Pigginf4fc66a2007-10-16 01:25:05 -07001219
1220 index = pos >> PAGE_CACHE_SHIFT;
1221 from = pos & (PAGE_CACHE_SIZE - 1);
1222 to = from + len;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001223
1224retry:
Nick Piggin54566b22009-01-04 12:00:53 -08001225 page = grab_cache_page_write_begin(mapping, index, flags);
Nick Pigginf4fc66a2007-10-16 01:25:05 -07001226 if (!page)
1227 return -ENOMEM;
1228 *pagep = page;
1229
Linus Torvalds1da177e2005-04-16 15:20:36 -07001230 handle = ext3_journal_start(inode, needed_blocks);
Andrew Morton1aa9b4b2007-04-01 23:49:43 -07001231 if (IS_ERR(handle)) {
Nick Pigginf4fc66a2007-10-16 01:25:05 -07001232 unlock_page(page);
1233 page_cache_release(page);
Andrew Morton1aa9b4b2007-04-01 23:49:43 -07001234 ret = PTR_ERR(handle);
1235 goto out;
1236 }
Christoph Hellwig6e1db882010-06-04 11:29:57 +02001237 ret = __block_write_begin(page, pos, len, ext3_get_block);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001238 if (ret)
Nick Pigginf4fc66a2007-10-16 01:25:05 -07001239 goto write_begin_failed;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001240
1241 if (ext3_should_journal_data(inode)) {
1242 ret = walk_page_buffers(handle, page_buffers(page),
1243 from, to, NULL, do_journal_get_write_access);
1244 }
Nick Pigginf4fc66a2007-10-16 01:25:05 -07001245write_begin_failed:
1246 if (ret) {
Aneesh Kumar K.V5ec8b752008-10-18 20:28:00 -07001247 /*
1248 * block_write_begin may have instantiated a few blocks
1249 * outside i_size. Trim these off again. Don't need
1250 * i_size_read because we hold i_mutex.
Jan Kara695f6ae2009-04-02 16:57:17 -07001251 *
1252 * Add inode to orphan list in case we crash before truncate
Jan Kara9eaaa2d2009-07-13 20:26:52 +02001253 * finishes. Do this only if ext3_can_truncate() agrees so
1254 * that orphan processing code is happy.
Aneesh Kumar K.V5ec8b752008-10-18 20:28:00 -07001255 */
Jan Kara9eaaa2d2009-07-13 20:26:52 +02001256 if (pos + len > inode->i_size && ext3_can_truncate(inode))
Jan Kara695f6ae2009-04-02 16:57:17 -07001257 ext3_orphan_add(handle, inode);
1258 ext3_journal_stop(handle);
1259 unlock_page(page);
1260 page_cache_release(page);
1261 if (pos + len > inode->i_size)
Jan Kara68eb3db2009-12-01 16:53:06 +01001262 ext3_truncate_failed_write(inode);
Nick Pigginf4fc66a2007-10-16 01:25:05 -07001263 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001264 if (ret == -ENOSPC && ext3_should_retry_alloc(inode->i_sb, &retries))
1265 goto retry;
Andrew Morton1aa9b4b2007-04-01 23:49:43 -07001266out:
Linus Torvalds1da177e2005-04-16 15:20:36 -07001267 return ret;
1268}
1269
Nick Pigginf4fc66a2007-10-16 01:25:05 -07001270
Andrew Mortond6859bf2006-03-26 01:38:03 -08001271int ext3_journal_dirty_data(handle_t *handle, struct buffer_head *bh)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001272{
1273 int err = journal_dirty_data(handle, bh);
1274 if (err)
Harvey Harrisone05b6b52008-04-28 02:16:15 -07001275 ext3_journal_abort_handle(__func__, __func__,
Nick Pigginf4fc66a2007-10-16 01:25:05 -07001276 bh, handle, err);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001277 return err;
1278}
1279
Jan Kara695f6ae2009-04-02 16:57:17 -07001280/* For ordered writepage and write_end functions */
1281static int journal_dirty_data_fn(handle_t *handle, struct buffer_head *bh)
1282{
1283 /*
1284 * Write could have mapped the buffer but it didn't copy the data in
1285 * yet. So avoid filing such buffer into a transaction.
1286 */
1287 if (buffer_mapped(bh) && buffer_uptodate(bh))
1288 return ext3_journal_dirty_data(handle, bh);
1289 return 0;
1290}
1291
Nick Pigginf4fc66a2007-10-16 01:25:05 -07001292/* For write_end() in data=journal mode */
1293static int write_end_fn(handle_t *handle, struct buffer_head *bh)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001294{
1295 if (!buffer_mapped(bh) || buffer_freed(bh))
1296 return 0;
1297 set_buffer_uptodate(bh);
1298 return ext3_journal_dirty_metadata(handle, bh);
1299}
1300
1301/*
Jan Kara695f6ae2009-04-02 16:57:17 -07001302 * This is nasty and subtle: ext3_write_begin() could have allocated blocks
1303 * for the whole page but later we failed to copy the data in. Update inode
1304 * size according to what we managed to copy. The rest is going to be
1305 * truncated in write_end function.
Nick Pigginf4fc66a2007-10-16 01:25:05 -07001306 */
Jan Kara695f6ae2009-04-02 16:57:17 -07001307static void update_file_sizes(struct inode *inode, loff_t pos, unsigned copied)
Nick Pigginf4fc66a2007-10-16 01:25:05 -07001308{
Jan Kara695f6ae2009-04-02 16:57:17 -07001309 /* What matters to us is i_disksize. We don't write i_size anywhere */
1310 if (pos + copied > inode->i_size)
1311 i_size_write(inode, pos + copied);
1312 if (pos + copied > EXT3_I(inode)->i_disksize) {
1313 EXT3_I(inode)->i_disksize = pos + copied;
Nick Pigginf4fc66a2007-10-16 01:25:05 -07001314 mark_inode_dirty(inode);
1315 }
Nick Pigginf4fc66a2007-10-16 01:25:05 -07001316}
1317
1318/*
Linus Torvalds1da177e2005-04-16 15:20:36 -07001319 * We need to pick up the new inode size which generic_commit_write gave us
1320 * `file' can be NULL - eg, when called from page_symlink().
1321 *
1322 * ext3 never places buffers on inode->i_mapping->private_list. metadata
1323 * buffers are managed internally.
1324 */
Nick Pigginf4fc66a2007-10-16 01:25:05 -07001325static int ext3_ordered_write_end(struct file *file,
1326 struct address_space *mapping,
1327 loff_t pos, unsigned len, unsigned copied,
1328 struct page *page, void *fsdata)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001329{
1330 handle_t *handle = ext3_journal_current_handle();
Nick Pigginf4fc66a2007-10-16 01:25:05 -07001331 struct inode *inode = file->f_mapping->host;
1332 unsigned from, to;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001333 int ret = 0, ret2;
1334
Jan Kara695f6ae2009-04-02 16:57:17 -07001335 copied = block_write_end(file, mapping, pos, len, copied, page, fsdata);
1336
Nick Pigginf4fc66a2007-10-16 01:25:05 -07001337 from = pos & (PAGE_CACHE_SIZE - 1);
Jan Kara695f6ae2009-04-02 16:57:17 -07001338 to = from + copied;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001339 ret = walk_page_buffers(handle, page_buffers(page),
Jan Kara695f6ae2009-04-02 16:57:17 -07001340 from, to, NULL, journal_dirty_data_fn);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001341
Jan Kara695f6ae2009-04-02 16:57:17 -07001342 if (ret == 0)
1343 update_file_sizes(inode, pos, copied);
1344 /*
1345 * There may be allocated blocks outside of i_size because
1346 * we failed to copy some data. Prepare for truncate.
1347 */
Jan Kara9eaaa2d2009-07-13 20:26:52 +02001348 if (pos + len > inode->i_size && ext3_can_truncate(inode))
Jan Kara695f6ae2009-04-02 16:57:17 -07001349 ext3_orphan_add(handle, inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001350 ret2 = ext3_journal_stop(handle);
1351 if (!ret)
1352 ret = ret2;
Nick Pigginf4fc66a2007-10-16 01:25:05 -07001353 unlock_page(page);
1354 page_cache_release(page);
1355
Jan Kara695f6ae2009-04-02 16:57:17 -07001356 if (pos + len > inode->i_size)
Jan Kara68eb3db2009-12-01 16:53:06 +01001357 ext3_truncate_failed_write(inode);
Nick Pigginf4fc66a2007-10-16 01:25:05 -07001358 return ret ? ret : copied;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001359}
1360
Nick Pigginf4fc66a2007-10-16 01:25:05 -07001361static int ext3_writeback_write_end(struct file *file,
1362 struct address_space *mapping,
1363 loff_t pos, unsigned len, unsigned copied,
1364 struct page *page, void *fsdata)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001365{
1366 handle_t *handle = ext3_journal_current_handle();
Nick Pigginf4fc66a2007-10-16 01:25:05 -07001367 struct inode *inode = file->f_mapping->host;
Jan Kara695f6ae2009-04-02 16:57:17 -07001368 int ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001369
Jan Kara695f6ae2009-04-02 16:57:17 -07001370 copied = block_write_end(file, mapping, pos, len, copied, page, fsdata);
1371 update_file_sizes(inode, pos, copied);
1372 /*
1373 * There may be allocated blocks outside of i_size because
1374 * we failed to copy some data. Prepare for truncate.
1375 */
Jan Kara9eaaa2d2009-07-13 20:26:52 +02001376 if (pos + len > inode->i_size && ext3_can_truncate(inode))
Jan Kara695f6ae2009-04-02 16:57:17 -07001377 ext3_orphan_add(handle, inode);
1378 ret = ext3_journal_stop(handle);
Nick Pigginf4fc66a2007-10-16 01:25:05 -07001379 unlock_page(page);
1380 page_cache_release(page);
1381
Jan Kara695f6ae2009-04-02 16:57:17 -07001382 if (pos + len > inode->i_size)
Jan Kara68eb3db2009-12-01 16:53:06 +01001383 ext3_truncate_failed_write(inode);
Nick Pigginf4fc66a2007-10-16 01:25:05 -07001384 return ret ? ret : copied;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001385}
1386
Nick Pigginf4fc66a2007-10-16 01:25:05 -07001387static int ext3_journalled_write_end(struct file *file,
1388 struct address_space *mapping,
1389 loff_t pos, unsigned len, unsigned copied,
1390 struct page *page, void *fsdata)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001391{
1392 handle_t *handle = ext3_journal_current_handle();
Nick Pigginf4fc66a2007-10-16 01:25:05 -07001393 struct inode *inode = mapping->host;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001394 int ret = 0, ret2;
1395 int partial = 0;
Nick Pigginf4fc66a2007-10-16 01:25:05 -07001396 unsigned from, to;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001397
Nick Pigginf4fc66a2007-10-16 01:25:05 -07001398 from = pos & (PAGE_CACHE_SIZE - 1);
1399 to = from + len;
1400
1401 if (copied < len) {
1402 if (!PageUptodate(page))
1403 copied = 0;
Jan Kara695f6ae2009-04-02 16:57:17 -07001404 page_zero_new_buffers(page, from + copied, to);
1405 to = from + copied;
Nick Pigginf4fc66a2007-10-16 01:25:05 -07001406 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001407
1408 ret = walk_page_buffers(handle, page_buffers(page), from,
Nick Pigginf4fc66a2007-10-16 01:25:05 -07001409 to, &partial, write_end_fn);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001410 if (!partial)
1411 SetPageUptodate(page);
Jan Kara695f6ae2009-04-02 16:57:17 -07001412
1413 if (pos + copied > inode->i_size)
1414 i_size_write(inode, pos + copied);
1415 /*
1416 * There may be allocated blocks outside of i_size because
1417 * we failed to copy some data. Prepare for truncate.
1418 */
Jan Kara9eaaa2d2009-07-13 20:26:52 +02001419 if (pos + len > inode->i_size && ext3_can_truncate(inode))
Jan Kara695f6ae2009-04-02 16:57:17 -07001420 ext3_orphan_add(handle, inode);
Jan Kara9df93932010-01-06 21:58:48 +01001421 ext3_set_inode_state(inode, EXT3_STATE_JDATA);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001422 if (inode->i_size > EXT3_I(inode)->i_disksize) {
1423 EXT3_I(inode)->i_disksize = inode->i_size;
1424 ret2 = ext3_mark_inode_dirty(handle, inode);
Mingming Caoae6ddcc2006-09-27 01:49:27 -07001425 if (!ret)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001426 ret = ret2;
1427 }
Nick Pigginf4fc66a2007-10-16 01:25:05 -07001428
Linus Torvalds1da177e2005-04-16 15:20:36 -07001429 ret2 = ext3_journal_stop(handle);
1430 if (!ret)
1431 ret = ret2;
Nick Pigginf4fc66a2007-10-16 01:25:05 -07001432 unlock_page(page);
1433 page_cache_release(page);
1434
Jan Kara695f6ae2009-04-02 16:57:17 -07001435 if (pos + len > inode->i_size)
Jan Kara68eb3db2009-12-01 16:53:06 +01001436 ext3_truncate_failed_write(inode);
Nick Pigginf4fc66a2007-10-16 01:25:05 -07001437 return ret ? ret : copied;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001438}
1439
Mingming Caoae6ddcc2006-09-27 01:49:27 -07001440/*
Linus Torvalds1da177e2005-04-16 15:20:36 -07001441 * bmap() is special. It gets used by applications such as lilo and by
1442 * the swapper to find the on-disk block of a specific piece of data.
1443 *
1444 * Naturally, this is dangerous if the block concerned is still in the
1445 * journal. If somebody makes a swapfile on an ext3 data-journaling
1446 * filesystem and enables swap, then they may get a nasty shock when the
1447 * data getting swapped to that swapfile suddenly gets overwritten by
1448 * the original zero's written out previously to the journal and
Mingming Caoae6ddcc2006-09-27 01:49:27 -07001449 * awaiting writeback in the kernel's buffer cache.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001450 *
1451 * So, if we see any bmap calls here on a modified, data-journaled file,
Mingming Caoae6ddcc2006-09-27 01:49:27 -07001452 * take extra steps to flush any blocks which might be in the cache.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001453 */
1454static sector_t ext3_bmap(struct address_space *mapping, sector_t block)
1455{
1456 struct inode *inode = mapping->host;
1457 journal_t *journal;
1458 int err;
1459
Jan Kara9df93932010-01-06 21:58:48 +01001460 if (ext3_test_inode_state(inode, EXT3_STATE_JDATA)) {
Mingming Caoae6ddcc2006-09-27 01:49:27 -07001461 /*
Linus Torvalds1da177e2005-04-16 15:20:36 -07001462 * This is a REALLY heavyweight approach, but the use of
1463 * bmap on dirty files is expected to be extremely rare:
1464 * only if we run lilo or swapon on a freshly made file
Mingming Caoae6ddcc2006-09-27 01:49:27 -07001465 * do we expect this to happen.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001466 *
1467 * (bmap requires CAP_SYS_RAWIO so this does not
1468 * represent an unprivileged user DOS attack --- we'd be
1469 * in trouble if mortal users could trigger this path at
Mingming Caoae6ddcc2006-09-27 01:49:27 -07001470 * will.)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001471 *
1472 * NB. EXT3_STATE_JDATA is not set on files other than
1473 * regular files. If somebody wants to bmap a directory
1474 * or symlink and gets confused because the buffer
1475 * hasn't yet been flushed to disk, they deserve
1476 * everything they get.
1477 */
1478
Jan Kara9df93932010-01-06 21:58:48 +01001479 ext3_clear_inode_state(inode, EXT3_STATE_JDATA);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001480 journal = EXT3_JOURNAL(inode);
1481 journal_lock_updates(journal);
1482 err = journal_flush(journal);
1483 journal_unlock_updates(journal);
1484
1485 if (err)
1486 return 0;
1487 }
1488
1489 return generic_block_bmap(mapping,block,ext3_get_block);
1490}
1491
1492static int bget_one(handle_t *handle, struct buffer_head *bh)
1493{
1494 get_bh(bh);
1495 return 0;
1496}
1497
1498static int bput_one(handle_t *handle, struct buffer_head *bh)
1499{
1500 put_bh(bh);
1501 return 0;
1502}
1503
Jan Kara9e80d402009-03-26 13:08:04 +01001504static int buffer_unmapped(handle_t *handle, struct buffer_head *bh)
1505{
1506 return !buffer_mapped(bh);
1507}
Jan Kara695f6ae2009-04-02 16:57:17 -07001508
Linus Torvalds1da177e2005-04-16 15:20:36 -07001509/*
1510 * Note that we always start a transaction even if we're not journalling
1511 * data. This is to preserve ordering: any hole instantiation within
1512 * __block_write_full_page -> ext3_get_block() should be journalled
1513 * along with the data so we don't crash and then get metadata which
1514 * refers to old data.
1515 *
1516 * In all journalling modes block_write_full_page() will start the I/O.
1517 *
1518 * Problem:
1519 *
1520 * ext3_writepage() -> kmalloc() -> __alloc_pages() -> page_launder() ->
1521 * ext3_writepage()
1522 *
1523 * Similar for:
1524 *
1525 * ext3_file_write() -> generic_file_write() -> __alloc_pages() -> ...
1526 *
1527 * Same applies to ext3_get_block(). We will deadlock on various things like
Arjan van de Ven97461512006-03-23 03:00:42 -08001528 * lock_journal and i_truncate_mutex.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001529 *
1530 * Setting PF_MEMALLOC here doesn't work - too many internal memory
1531 * allocations fail.
1532 *
1533 * 16May01: If we're reentered then journal_current_handle() will be
1534 * non-zero. We simply *return*.
1535 *
1536 * 1 July 2001: @@@ FIXME:
1537 * In journalled data mode, a data buffer may be metadata against the
1538 * current transaction. But the same file is part of a shared mapping
1539 * and someone does a writepage() on it.
1540 *
1541 * We will move the buffer onto the async_data list, but *after* it has
1542 * been dirtied. So there's a small window where we have dirty data on
1543 * BJ_Metadata.
1544 *
1545 * Note that this only applies to the last partial page in the file. The
1546 * bit which block_write_full_page() uses prepare/commit for. (That's
1547 * broken code anyway: it's wrong for msync()).
1548 *
1549 * It's a rare case: affects the final partial page, for journalled data
1550 * where the file is subject to bith write() and writepage() in the same
1551 * transction. To fix it we'll need a custom block_write_full_page().
1552 * We'll probably need that anyway for journalling writepage() output.
1553 *
1554 * We don't honour synchronous mounts for writepage(). That would be
1555 * disastrous. Any write() or metadata operation will sync the fs for
1556 * us.
1557 *
1558 * AKPM2: if all the page's buffers are mapped to disk and !data=journal,
1559 * we don't need to open a transaction here.
1560 */
1561static int ext3_ordered_writepage(struct page *page,
Andrew Mortond6859bf2006-03-26 01:38:03 -08001562 struct writeback_control *wbc)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001563{
1564 struct inode *inode = page->mapping->host;
1565 struct buffer_head *page_bufs;
1566 handle_t *handle = NULL;
1567 int ret = 0;
1568 int err;
1569
1570 J_ASSERT(PageLocked(page));
Dmitry Monakhov49792c82010-03-02 15:51:02 +03001571 WARN_ON_ONCE(IS_RDONLY(inode));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001572
1573 /*
1574 * We give up here if we're reentered, because it might be for a
1575 * different filesystem.
1576 */
1577 if (ext3_journal_current_handle())
1578 goto out_fail;
1579
Jan Kara9e80d402009-03-26 13:08:04 +01001580 if (!page_has_buffers(page)) {
1581 create_empty_buffers(page, inode->i_sb->s_blocksize,
1582 (1 << BH_Dirty)|(1 << BH_Uptodate));
Jan Kara430db322009-04-07 18:25:01 -04001583 page_bufs = page_buffers(page);
1584 } else {
1585 page_bufs = page_buffers(page);
1586 if (!walk_page_buffers(NULL, page_bufs, 0, PAGE_CACHE_SIZE,
1587 NULL, buffer_unmapped)) {
1588 /* Provide NULL get_block() to catch bugs if buffers
1589 * weren't really mapped */
1590 return block_write_full_page(page, NULL, wbc);
1591 }
Jan Kara9e80d402009-03-26 13:08:04 +01001592 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001593 handle = ext3_journal_start(inode, ext3_writepage_trans_blocks(inode));
1594
1595 if (IS_ERR(handle)) {
1596 ret = PTR_ERR(handle);
1597 goto out_fail;
1598 }
1599
Linus Torvalds1da177e2005-04-16 15:20:36 -07001600 walk_page_buffers(handle, page_bufs, 0,
1601 PAGE_CACHE_SIZE, NULL, bget_one);
1602
1603 ret = block_write_full_page(page, ext3_get_block, wbc);
1604
1605 /*
1606 * The page can become unlocked at any point now, and
1607 * truncate can then come in and change things. So we
1608 * can't touch *page from now on. But *page_bufs is
1609 * safe due to elevated refcount.
1610 */
1611
1612 /*
Mingming Caoae6ddcc2006-09-27 01:49:27 -07001613 * And attach them to the current transaction. But only if
Linus Torvalds1da177e2005-04-16 15:20:36 -07001614 * block_write_full_page() succeeded. Otherwise they are unmapped,
1615 * and generally junk.
1616 */
1617 if (ret == 0) {
1618 err = walk_page_buffers(handle, page_bufs, 0, PAGE_CACHE_SIZE,
1619 NULL, journal_dirty_data_fn);
1620 if (!ret)
1621 ret = err;
1622 }
1623 walk_page_buffers(handle, page_bufs, 0,
1624 PAGE_CACHE_SIZE, NULL, bput_one);
1625 err = ext3_journal_stop(handle);
1626 if (!ret)
1627 ret = err;
1628 return ret;
1629
1630out_fail:
1631 redirty_page_for_writepage(wbc, page);
1632 unlock_page(page);
1633 return ret;
1634}
1635
Linus Torvalds1da177e2005-04-16 15:20:36 -07001636static int ext3_writeback_writepage(struct page *page,
1637 struct writeback_control *wbc)
1638{
1639 struct inode *inode = page->mapping->host;
1640 handle_t *handle = NULL;
1641 int ret = 0;
1642 int err;
1643
Dmitry Monakhov49792c82010-03-02 15:51:02 +03001644 J_ASSERT(PageLocked(page));
1645 WARN_ON_ONCE(IS_RDONLY(inode));
1646
Linus Torvalds1da177e2005-04-16 15:20:36 -07001647 if (ext3_journal_current_handle())
1648 goto out_fail;
1649
Jan Kara430db322009-04-07 18:25:01 -04001650 if (page_has_buffers(page)) {
1651 if (!walk_page_buffers(NULL, page_buffers(page), 0,
1652 PAGE_CACHE_SIZE, NULL, buffer_unmapped)) {
1653 /* Provide NULL get_block() to catch bugs if buffers
1654 * weren't really mapped */
1655 return block_write_full_page(page, NULL, wbc);
1656 }
1657 }
1658
Linus Torvalds1da177e2005-04-16 15:20:36 -07001659 handle = ext3_journal_start(inode, ext3_writepage_trans_blocks(inode));
1660 if (IS_ERR(handle)) {
1661 ret = PTR_ERR(handle);
1662 goto out_fail;
1663 }
1664
Christoph Hellwig4c4d3902010-06-07 10:20:39 +02001665 ret = block_write_full_page(page, ext3_get_block, wbc);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001666
1667 err = ext3_journal_stop(handle);
1668 if (!ret)
1669 ret = err;
1670 return ret;
1671
1672out_fail:
1673 redirty_page_for_writepage(wbc, page);
1674 unlock_page(page);
1675 return ret;
1676}
1677
1678static int ext3_journalled_writepage(struct page *page,
1679 struct writeback_control *wbc)
1680{
1681 struct inode *inode = page->mapping->host;
1682 handle_t *handle = NULL;
1683 int ret = 0;
1684 int err;
1685
Dmitry Monakhov49792c82010-03-02 15:51:02 +03001686 J_ASSERT(PageLocked(page));
1687 WARN_ON_ONCE(IS_RDONLY(inode));
1688
Linus Torvalds1da177e2005-04-16 15:20:36 -07001689 if (ext3_journal_current_handle())
1690 goto no_write;
1691
1692 handle = ext3_journal_start(inode, ext3_writepage_trans_blocks(inode));
1693 if (IS_ERR(handle)) {
1694 ret = PTR_ERR(handle);
1695 goto no_write;
1696 }
1697
1698 if (!page_has_buffers(page) || PageChecked(page)) {
1699 /*
1700 * It's mmapped pagecache. Add buffers and journal it. There
1701 * doesn't seem much point in redirtying the page here.
1702 */
1703 ClearPageChecked(page);
Christoph Hellwigebdec242010-10-06 10:47:23 +02001704 ret = __block_write_begin(page, 0, PAGE_CACHE_SIZE,
1705 ext3_get_block);
Denis Lunevab4eb432005-11-13 16:07:17 -08001706 if (ret != 0) {
1707 ext3_journal_stop(handle);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001708 goto out_unlock;
Denis Lunevab4eb432005-11-13 16:07:17 -08001709 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001710 ret = walk_page_buffers(handle, page_buffers(page), 0,
1711 PAGE_CACHE_SIZE, NULL, do_journal_get_write_access);
1712
1713 err = walk_page_buffers(handle, page_buffers(page), 0,
Nick Pigginf4fc66a2007-10-16 01:25:05 -07001714 PAGE_CACHE_SIZE, NULL, write_end_fn);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001715 if (ret == 0)
1716 ret = err;
Jan Kara9df93932010-01-06 21:58:48 +01001717 ext3_set_inode_state(inode, EXT3_STATE_JDATA);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001718 unlock_page(page);
1719 } else {
1720 /*
1721 * It may be a page full of checkpoint-mode buffers. We don't
1722 * really know unless we go poke around in the buffer_heads.
1723 * But block_write_full_page will do the right thing.
1724 */
1725 ret = block_write_full_page(page, ext3_get_block, wbc);
1726 }
1727 err = ext3_journal_stop(handle);
1728 if (!ret)
1729 ret = err;
1730out:
1731 return ret;
1732
1733no_write:
1734 redirty_page_for_writepage(wbc, page);
1735out_unlock:
1736 unlock_page(page);
1737 goto out;
1738}
1739
1740static int ext3_readpage(struct file *file, struct page *page)
1741{
1742 return mpage_readpage(page, ext3_get_block);
1743}
1744
1745static int
1746ext3_readpages(struct file *file, struct address_space *mapping,
1747 struct list_head *pages, unsigned nr_pages)
1748{
1749 return mpage_readpages(mapping, pages, nr_pages, ext3_get_block);
1750}
1751
NeilBrown2ff28e22006-03-26 01:37:18 -08001752static void ext3_invalidatepage(struct page *page, unsigned long offset)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001753{
1754 journal_t *journal = EXT3_JOURNAL(page->mapping->host);
1755
1756 /*
1757 * If it's a full truncate we just forget about the pending dirtying
1758 */
1759 if (offset == 0)
1760 ClearPageChecked(page);
1761
NeilBrown2ff28e22006-03-26 01:37:18 -08001762 journal_invalidatepage(journal, page, offset);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001763}
1764
Al Viro27496a82005-10-21 03:20:48 -04001765static int ext3_releasepage(struct page *page, gfp_t wait)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001766{
1767 journal_t *journal = EXT3_JOURNAL(page->mapping->host);
1768
1769 WARN_ON(PageChecked(page));
1770 if (!page_has_buffers(page))
1771 return 0;
1772 return journal_try_to_free_buffers(journal, page, wait);
1773}
1774
1775/*
1776 * If the O_DIRECT write will extend the file then add this inode to the
1777 * orphan list. So recovery will truncate it back to the original size
1778 * if the machine crashes during the write.
1779 *
1780 * If the O_DIRECT write is intantiating holes inside i_size and the machine
Jan Karabd1939d2008-02-06 01:40:21 -08001781 * crashes then stale disk data _may_ be exposed inside the file. But current
1782 * VFS code falls back into buffered path in that case so we are safe.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001783 */
1784static ssize_t ext3_direct_IO(int rw, struct kiocb *iocb,
1785 const struct iovec *iov, loff_t offset,
1786 unsigned long nr_segs)
1787{
1788 struct file *file = iocb->ki_filp;
1789 struct inode *inode = file->f_mapping->host;
1790 struct ext3_inode_info *ei = EXT3_I(inode);
Jan Karabd1939d2008-02-06 01:40:21 -08001791 handle_t *handle;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001792 ssize_t ret;
1793 int orphan = 0;
1794 size_t count = iov_length(iov, nr_segs);
Eric Sandeenea0174a2009-10-12 21:34:27 -05001795 int retries = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001796
1797 if (rw == WRITE) {
1798 loff_t final_size = offset + count;
1799
Linus Torvalds1da177e2005-04-16 15:20:36 -07001800 if (final_size > inode->i_size) {
Jan Karabd1939d2008-02-06 01:40:21 -08001801 /* Credits for sb + inode write */
1802 handle = ext3_journal_start(inode, 2);
1803 if (IS_ERR(handle)) {
1804 ret = PTR_ERR(handle);
1805 goto out;
1806 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001807 ret = ext3_orphan_add(handle, inode);
Jan Karabd1939d2008-02-06 01:40:21 -08001808 if (ret) {
1809 ext3_journal_stop(handle);
1810 goto out;
1811 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001812 orphan = 1;
1813 ei->i_disksize = inode->i_size;
Jan Karabd1939d2008-02-06 01:40:21 -08001814 ext3_journal_stop(handle);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001815 }
1816 }
1817
Eric Sandeenea0174a2009-10-12 21:34:27 -05001818retry:
Mingming Caoae6ddcc2006-09-27 01:49:27 -07001819 ret = blockdev_direct_IO(rw, iocb, inode, inode->i_sb->s_bdev, iov,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001820 offset, nr_segs,
Badari Pulavartyf91a2ad2006-03-26 01:38:04 -08001821 ext3_get_block, NULL);
Christoph Hellwigeafdc7d2010-06-04 11:29:53 +02001822 /*
1823 * In case of error extending write may have instantiated a few
1824 * blocks outside i_size. Trim these off again.
1825 */
1826 if (unlikely((rw & WRITE) && ret < 0)) {
1827 loff_t isize = i_size_read(inode);
1828 loff_t end = offset + iov_length(iov, nr_segs);
1829
1830 if (end > isize)
1831 vmtruncate(inode, isize);
1832 }
Eric Sandeenea0174a2009-10-12 21:34:27 -05001833 if (ret == -ENOSPC && ext3_should_retry_alloc(inode->i_sb, &retries))
1834 goto retry;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001835
Jan Karabd1939d2008-02-06 01:40:21 -08001836 if (orphan) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001837 int err;
1838
Jan Karabd1939d2008-02-06 01:40:21 -08001839 /* Credits for sb + inode write */
1840 handle = ext3_journal_start(inode, 2);
1841 if (IS_ERR(handle)) {
1842 /* This is really bad luck. We've written the data
Jan Kara7eb49692010-03-01 14:02:37 +01001843 * but cannot extend i_size. Truncate allocated blocks
1844 * and pretend the write failed... */
1845 ext3_truncate(inode);
Jan Karabd1939d2008-02-06 01:40:21 -08001846 ret = PTR_ERR(handle);
1847 goto out;
1848 }
1849 if (inode->i_nlink)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001850 ext3_orphan_del(handle, inode);
Jan Karabd1939d2008-02-06 01:40:21 -08001851 if (ret > 0) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001852 loff_t end = offset + ret;
1853 if (end > inode->i_size) {
1854 ei->i_disksize = end;
1855 i_size_write(inode, end);
1856 /*
1857 * We're going to return a positive `ret'
1858 * here due to non-zero-length I/O, so there's
1859 * no way of reporting error returns from
1860 * ext3_mark_inode_dirty() to userspace. So
1861 * ignore it.
1862 */
1863 ext3_mark_inode_dirty(handle, inode);
1864 }
1865 }
1866 err = ext3_journal_stop(handle);
1867 if (ret == 0)
1868 ret = err;
1869 }
1870out:
1871 return ret;
1872}
1873
1874/*
1875 * Pages can be marked dirty completely asynchronously from ext3's journalling
1876 * activity. By filemap_sync_pte(), try_to_unmap_one(), etc. We cannot do
1877 * much here because ->set_page_dirty is called under VFS locks. The page is
1878 * not necessarily locked.
1879 *
1880 * We cannot just dirty the page and leave attached buffers clean, because the
1881 * buffers' dirty state is "definitive". We cannot just set the buffers dirty
1882 * or jbddirty because all the journalling code will explode.
1883 *
1884 * So what we do is to mark the page "pending dirty" and next time writepage
1885 * is called, propagate that into the buffers appropriately.
1886 */
1887static int ext3_journalled_set_page_dirty(struct page *page)
1888{
1889 SetPageChecked(page);
1890 return __set_page_dirty_nobuffers(page);
1891}
1892
Christoph Hellwigf5e54d62006-06-28 04:26:44 -07001893static const struct address_space_operations ext3_ordered_aops = {
Hisashi Hifumi8ab22b92008-07-28 15:46:36 -07001894 .readpage = ext3_readpage,
1895 .readpages = ext3_readpages,
1896 .writepage = ext3_ordered_writepage,
Hisashi Hifumi8ab22b92008-07-28 15:46:36 -07001897 .write_begin = ext3_write_begin,
1898 .write_end = ext3_ordered_write_end,
1899 .bmap = ext3_bmap,
1900 .invalidatepage = ext3_invalidatepage,
1901 .releasepage = ext3_releasepage,
1902 .direct_IO = ext3_direct_IO,
1903 .migratepage = buffer_migrate_page,
1904 .is_partially_uptodate = block_is_partially_uptodate,
Andi Kleenaa261f52009-09-16 11:50:16 +02001905 .error_remove_page = generic_error_remove_page,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001906};
1907
Christoph Hellwigf5e54d62006-06-28 04:26:44 -07001908static const struct address_space_operations ext3_writeback_aops = {
Hisashi Hifumi8ab22b92008-07-28 15:46:36 -07001909 .readpage = ext3_readpage,
1910 .readpages = ext3_readpages,
1911 .writepage = ext3_writeback_writepage,
Hisashi Hifumi8ab22b92008-07-28 15:46:36 -07001912 .write_begin = ext3_write_begin,
1913 .write_end = ext3_writeback_write_end,
1914 .bmap = ext3_bmap,
1915 .invalidatepage = ext3_invalidatepage,
1916 .releasepage = ext3_releasepage,
1917 .direct_IO = ext3_direct_IO,
1918 .migratepage = buffer_migrate_page,
1919 .is_partially_uptodate = block_is_partially_uptodate,
Andi Kleenaa261f52009-09-16 11:50:16 +02001920 .error_remove_page = generic_error_remove_page,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001921};
1922
Christoph Hellwigf5e54d62006-06-28 04:26:44 -07001923static const struct address_space_operations ext3_journalled_aops = {
Hisashi Hifumi8ab22b92008-07-28 15:46:36 -07001924 .readpage = ext3_readpage,
1925 .readpages = ext3_readpages,
1926 .writepage = ext3_journalled_writepage,
Hisashi Hifumi8ab22b92008-07-28 15:46:36 -07001927 .write_begin = ext3_write_begin,
1928 .write_end = ext3_journalled_write_end,
1929 .set_page_dirty = ext3_journalled_set_page_dirty,
1930 .bmap = ext3_bmap,
1931 .invalidatepage = ext3_invalidatepage,
1932 .releasepage = ext3_releasepage,
1933 .is_partially_uptodate = block_is_partially_uptodate,
Andi Kleenaa261f52009-09-16 11:50:16 +02001934 .error_remove_page = generic_error_remove_page,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001935};
1936
1937void ext3_set_aops(struct inode *inode)
1938{
1939 if (ext3_should_order_data(inode))
1940 inode->i_mapping->a_ops = &ext3_ordered_aops;
1941 else if (ext3_should_writeback_data(inode))
1942 inode->i_mapping->a_ops = &ext3_writeback_aops;
1943 else
1944 inode->i_mapping->a_ops = &ext3_journalled_aops;
1945}
1946
1947/*
1948 * ext3_block_truncate_page() zeroes out a mapping from file offset `from'
1949 * up to the end of the block which corresponds to `from'.
1950 * This required during truncate. We need to physically zero the tail end
1951 * of that block so it doesn't yield old data if the file is later grown.
1952 */
1953static int ext3_block_truncate_page(handle_t *handle, struct page *page,
1954 struct address_space *mapping, loff_t from)
1955{
Mingming Cao43d23f92006-06-25 05:48:07 -07001956 ext3_fsblk_t index = from >> PAGE_CACHE_SHIFT;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001957 unsigned offset = from & (PAGE_CACHE_SIZE-1);
1958 unsigned blocksize, iblock, length, pos;
1959 struct inode *inode = mapping->host;
1960 struct buffer_head *bh;
1961 int err = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001962
1963 blocksize = inode->i_sb->s_blocksize;
1964 length = blocksize - (offset & (blocksize - 1));
1965 iblock = index << (PAGE_CACHE_SHIFT - inode->i_sb->s_blocksize_bits);
1966
Linus Torvalds1da177e2005-04-16 15:20:36 -07001967 if (!page_has_buffers(page))
1968 create_empty_buffers(page, blocksize, 0);
1969
1970 /* Find the buffer that contains "offset" */
1971 bh = page_buffers(page);
1972 pos = blocksize;
1973 while (offset >= pos) {
1974 bh = bh->b_this_page;
1975 iblock++;
1976 pos += blocksize;
1977 }
1978
1979 err = 0;
1980 if (buffer_freed(bh)) {
1981 BUFFER_TRACE(bh, "freed: skip");
1982 goto unlock;
1983 }
1984
1985 if (!buffer_mapped(bh)) {
1986 BUFFER_TRACE(bh, "unmapped");
1987 ext3_get_block(inode, iblock, bh, 0);
1988 /* unmapped? It's a hole - nothing to do */
1989 if (!buffer_mapped(bh)) {
1990 BUFFER_TRACE(bh, "still unmapped");
1991 goto unlock;
1992 }
1993 }
1994
1995 /* Ok, it's mapped. Make sure it's up-to-date */
1996 if (PageUptodate(page))
1997 set_buffer_uptodate(bh);
1998
1999 if (!buffer_uptodate(bh)) {
2000 err = -EIO;
2001 ll_rw_block(READ, 1, &bh);
2002 wait_on_buffer(bh);
2003 /* Uhhuh. Read error. Complain and punt. */
2004 if (!buffer_uptodate(bh))
2005 goto unlock;
2006 }
2007
2008 if (ext3_should_journal_data(inode)) {
2009 BUFFER_TRACE(bh, "get write access");
2010 err = ext3_journal_get_write_access(handle, bh);
2011 if (err)
2012 goto unlock;
2013 }
2014
Christoph Lametereebd2aa2008-02-04 22:28:29 -08002015 zero_user(page, offset, length);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002016 BUFFER_TRACE(bh, "zeroed end of block");
2017
2018 err = 0;
2019 if (ext3_should_journal_data(inode)) {
2020 err = ext3_journal_dirty_metadata(handle, bh);
2021 } else {
2022 if (ext3_should_order_data(inode))
2023 err = ext3_journal_dirty_data(handle, bh);
2024 mark_buffer_dirty(bh);
2025 }
2026
2027unlock:
2028 unlock_page(page);
2029 page_cache_release(page);
2030 return err;
2031}
2032
2033/*
2034 * Probably it should be a library function... search for first non-zero word
2035 * or memcmp with zero_page, whatever is better for particular architecture.
2036 * Linus?
2037 */
2038static inline int all_zeroes(__le32 *p, __le32 *q)
2039{
2040 while (p < q)
2041 if (*p++)
2042 return 0;
2043 return 1;
2044}
2045
2046/**
2047 * ext3_find_shared - find the indirect blocks for partial truncation.
2048 * @inode: inode in question
2049 * @depth: depth of the affected branch
2050 * @offsets: offsets of pointers in that branch (see ext3_block_to_path)
2051 * @chain: place to store the pointers to partial indirect blocks
2052 * @top: place to the (detached) top of branch
2053 *
2054 * This is a helper function used by ext3_truncate().
2055 *
2056 * When we do truncate() we may have to clean the ends of several
2057 * indirect blocks but leave the blocks themselves alive. Block is
Lucas De Marchi25985ed2011-03-30 22:57:33 -03002058 * partially truncated if some data below the new i_size is referred
Linus Torvalds1da177e2005-04-16 15:20:36 -07002059 * from it (and it is on the path to the first completely truncated
2060 * data block, indeed). We have to free the top of that path along
2061 * with everything to the right of the path. Since no allocation
2062 * past the truncation point is possible until ext3_truncate()
2063 * finishes, we may safely do the latter, but top of branch may
2064 * require special attention - pageout below the truncation point
2065 * might try to populate it.
2066 *
2067 * We atomically detach the top of branch from the tree, store the
2068 * block number of its root in *@top, pointers to buffer_heads of
2069 * partially truncated blocks - in @chain[].bh and pointers to
2070 * their last elements that should not be removed - in
2071 * @chain[].p. Return value is the pointer to last filled element
2072 * of @chain.
2073 *
2074 * The work left to caller to do the actual freeing of subtrees:
2075 * a) free the subtree starting from *@top
2076 * b) free the subtrees whose roots are stored in
2077 * (@chain[i].p+1 .. end of @chain[i].bh->b_data)
2078 * c) free the subtrees growing from the inode past the @chain[0].
2079 * (no partially truncated stuff there). */
2080
Andrew Mortond6859bf2006-03-26 01:38:03 -08002081static Indirect *ext3_find_shared(struct inode *inode, int depth,
2082 int offsets[4], Indirect chain[4], __le32 *top)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002083{
2084 Indirect *partial, *p;
2085 int k, err;
2086
2087 *top = 0;
Uwe Kleine-Königbf48aab2009-10-28 20:11:03 +01002088 /* Make k index the deepest non-null offset + 1 */
Linus Torvalds1da177e2005-04-16 15:20:36 -07002089 for (k = depth; k > 1 && !offsets[k-1]; k--)
2090 ;
2091 partial = ext3_get_branch(inode, k, offsets, chain, &err);
2092 /* Writer: pointers */
2093 if (!partial)
2094 partial = chain + k-1;
2095 /*
2096 * If the branch acquired continuation since we've looked at it -
2097 * fine, it should all survive and (new) top doesn't belong to us.
2098 */
2099 if (!partial->key && *partial->p)
2100 /* Writer: end */
2101 goto no_top;
2102 for (p=partial; p>chain && all_zeroes((__le32*)p->bh->b_data,p->p); p--)
2103 ;
2104 /*
2105 * OK, we've found the last block that must survive. The rest of our
2106 * branch should be detached before unlocking. However, if that rest
2107 * of branch is all ours and does not grow immediately from the inode
2108 * it's easier to cheat and just decrement partial->p.
2109 */
2110 if (p == chain + k - 1 && p > chain) {
2111 p->p--;
2112 } else {
2113 *top = *p->p;
2114 /* Nope, don't do this in ext3. Must leave the tree intact */
2115#if 0
2116 *p->p = 0;
2117#endif
2118 }
2119 /* Writer: end */
2120
Andrew Mortond6859bf2006-03-26 01:38:03 -08002121 while(partial > p) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002122 brelse(partial->bh);
2123 partial--;
2124 }
2125no_top:
2126 return partial;
2127}
2128
2129/*
2130 * Zero a number of block pointers in either an inode or an indirect block.
2131 * If we restart the transaction we must again get write access to the
2132 * indirect block for further modification.
2133 *
2134 * We release `count' blocks on disk, but (last - first) may be greater
2135 * than `count' because there can be holes in there.
2136 */
Andrew Mortond6859bf2006-03-26 01:38:03 -08002137static void ext3_clear_blocks(handle_t *handle, struct inode *inode,
Mingming Cao43d23f92006-06-25 05:48:07 -07002138 struct buffer_head *bh, ext3_fsblk_t block_to_free,
Andrew Mortond6859bf2006-03-26 01:38:03 -08002139 unsigned long count, __le32 *first, __le32 *last)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002140{
2141 __le32 *p;
2142 if (try_to_extend_transaction(handle, inode)) {
2143 if (bh) {
2144 BUFFER_TRACE(bh, "call ext3_journal_dirty_metadata");
Namhyung Kim156e7432010-11-25 01:53:13 +09002145 if (ext3_journal_dirty_metadata(handle, bh))
2146 return;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002147 }
2148 ext3_mark_inode_dirty(handle, inode);
Jan Kara00171d32009-08-11 19:06:10 +02002149 truncate_restart_transaction(handle, inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002150 if (bh) {
2151 BUFFER_TRACE(bh, "retaking write access");
Namhyung Kim156e7432010-11-25 01:53:13 +09002152 if (ext3_journal_get_write_access(handle, bh))
2153 return;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002154 }
2155 }
2156
2157 /*
2158 * Any buffers which are on the journal will be in memory. We find
2159 * them on the hash table so journal_revoke() will run journal_forget()
2160 * on them. We've already detached each block from the file, so
2161 * bforget() in journal_forget() should be safe.
2162 *
2163 * AKPM: turn on bforget in journal_forget()!!!
2164 */
2165 for (p = first; p < last; p++) {
2166 u32 nr = le32_to_cpu(*p);
2167 if (nr) {
2168 struct buffer_head *bh;
2169
2170 *p = 0;
2171 bh = sb_find_get_block(inode->i_sb, nr);
2172 ext3_forget(handle, 0, inode, bh, nr);
2173 }
2174 }
2175
2176 ext3_free_blocks(handle, inode, block_to_free, count);
2177}
2178
2179/**
2180 * ext3_free_data - free a list of data blocks
2181 * @handle: handle for this transaction
2182 * @inode: inode we are dealing with
2183 * @this_bh: indirect buffer_head which contains *@first and *@last
2184 * @first: array of block numbers
2185 * @last: points immediately past the end of array
2186 *
Lucas De Marchi25985ed2011-03-30 22:57:33 -03002187 * We are freeing all blocks referred from that array (numbers are stored as
Linus Torvalds1da177e2005-04-16 15:20:36 -07002188 * little-endian 32-bit) and updating @inode->i_blocks appropriately.
2189 *
2190 * We accumulate contiguous runs of blocks to free. Conveniently, if these
2191 * blocks are contiguous then releasing them at one time will only affect one
2192 * or two bitmap blocks (+ group descriptor(s) and superblock) and we won't
2193 * actually use a lot of journal space.
2194 *
2195 * @this_bh will be %NULL if @first and @last point into the inode's direct
2196 * block pointers.
2197 */
2198static void ext3_free_data(handle_t *handle, struct inode *inode,
2199 struct buffer_head *this_bh,
2200 __le32 *first, __le32 *last)
2201{
Mingming Cao43d23f92006-06-25 05:48:07 -07002202 ext3_fsblk_t block_to_free = 0; /* Starting block # of a run */
Mingming Caoae6ddcc2006-09-27 01:49:27 -07002203 unsigned long count = 0; /* Number of blocks in the run */
Linus Torvalds1da177e2005-04-16 15:20:36 -07002204 __le32 *block_to_free_p = NULL; /* Pointer into inode/ind
2205 corresponding to
2206 block_to_free */
Mingming Cao43d23f92006-06-25 05:48:07 -07002207 ext3_fsblk_t nr; /* Current block # */
Linus Torvalds1da177e2005-04-16 15:20:36 -07002208 __le32 *p; /* Pointer into inode/ind
2209 for current block */
2210 int err;
2211
2212 if (this_bh) { /* For indirect block */
2213 BUFFER_TRACE(this_bh, "get_write_access");
2214 err = ext3_journal_get_write_access(handle, this_bh);
2215 /* Important: if we can't update the indirect pointers
2216 * to the blocks, we can't free them. */
2217 if (err)
2218 return;
2219 }
2220
2221 for (p = first; p < last; p++) {
2222 nr = le32_to_cpu(*p);
2223 if (nr) {
2224 /* accumulate blocks to free if they're contiguous */
2225 if (count == 0) {
2226 block_to_free = nr;
2227 block_to_free_p = p;
2228 count = 1;
2229 } else if (nr == block_to_free + count) {
2230 count++;
2231 } else {
Mingming Caoae6ddcc2006-09-27 01:49:27 -07002232 ext3_clear_blocks(handle, inode, this_bh,
Linus Torvalds1da177e2005-04-16 15:20:36 -07002233 block_to_free,
2234 count, block_to_free_p, p);
2235 block_to_free = nr;
2236 block_to_free_p = p;
2237 count = 1;
2238 }
2239 }
2240 }
2241
2242 if (count > 0)
2243 ext3_clear_blocks(handle, inode, this_bh, block_to_free,
2244 count, block_to_free_p, p);
2245
2246 if (this_bh) {
2247 BUFFER_TRACE(this_bh, "call ext3_journal_dirty_metadata");
Duane Griffin3ccc3162008-07-25 01:46:26 -07002248
2249 /*
2250 * The buffer head should have an attached journal head at this
2251 * point. However, if the data is corrupted and an indirect
2252 * block pointed to itself, it would have been detached when
2253 * the block was cleared. Check for this instead of OOPSing.
2254 */
2255 if (bh2jh(this_bh))
2256 ext3_journal_dirty_metadata(handle, this_bh);
2257 else
2258 ext3_error(inode->i_sb, "ext3_free_data",
2259 "circular indirect block detected, "
2260 "inode=%lu, block=%llu",
2261 inode->i_ino,
2262 (unsigned long long)this_bh->b_blocknr);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002263 }
2264}
2265
2266/**
2267 * ext3_free_branches - free an array of branches
2268 * @handle: JBD handle for this transaction
2269 * @inode: inode we are dealing with
2270 * @parent_bh: the buffer_head which contains *@first and *@last
2271 * @first: array of block numbers
2272 * @last: pointer immediately past the end of array
2273 * @depth: depth of the branches to free
2274 *
Lucas De Marchi25985ed2011-03-30 22:57:33 -03002275 * We are freeing all blocks referred from these branches (numbers are
Linus Torvalds1da177e2005-04-16 15:20:36 -07002276 * stored as little-endian 32-bit) and updating @inode->i_blocks
2277 * appropriately.
2278 */
2279static void ext3_free_branches(handle_t *handle, struct inode *inode,
2280 struct buffer_head *parent_bh,
2281 __le32 *first, __le32 *last, int depth)
2282{
Mingming Cao43d23f92006-06-25 05:48:07 -07002283 ext3_fsblk_t nr;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002284 __le32 *p;
2285
2286 if (is_handle_aborted(handle))
2287 return;
2288
2289 if (depth--) {
2290 struct buffer_head *bh;
2291 int addr_per_block = EXT3_ADDR_PER_BLOCK(inode->i_sb);
2292 p = last;
2293 while (--p >= first) {
2294 nr = le32_to_cpu(*p);
2295 if (!nr)
2296 continue; /* A hole */
2297
2298 /* Go read the buffer for the next level down */
2299 bh = sb_bread(inode->i_sb, nr);
2300
2301 /*
2302 * A read failure? Report error and clear slot
2303 * (should be rare).
2304 */
2305 if (!bh) {
2306 ext3_error(inode->i_sb, "ext3_free_branches",
Eric Sandeeneee194e2006-09-27 01:49:30 -07002307 "Read failure, inode=%lu, block="E3FSBLK,
Linus Torvalds1da177e2005-04-16 15:20:36 -07002308 inode->i_ino, nr);
2309 continue;
2310 }
2311
2312 /* This zaps the entire block. Bottom up. */
2313 BUFFER_TRACE(bh, "free child branches");
2314 ext3_free_branches(handle, inode, bh,
2315 (__le32*)bh->b_data,
2316 (__le32*)bh->b_data + addr_per_block,
2317 depth);
2318
2319 /*
Linus Torvalds1da177e2005-04-16 15:20:36 -07002320 * Everything below this this pointer has been
2321 * released. Now let this top-of-subtree go.
2322 *
2323 * We want the freeing of this indirect block to be
2324 * atomic in the journal with the updating of the
2325 * bitmap block which owns it. So make some room in
2326 * the journal.
2327 *
2328 * We zero the parent pointer *after* freeing its
2329 * pointee in the bitmaps, so if extend_transaction()
2330 * for some reason fails to put the bitmap changes and
2331 * the release into the same transaction, recovery
2332 * will merely complain about releasing a free block,
2333 * rather than leaking blocks.
2334 */
2335 if (is_handle_aborted(handle))
2336 return;
2337 if (try_to_extend_transaction(handle, inode)) {
2338 ext3_mark_inode_dirty(handle, inode);
Jan Kara00171d32009-08-11 19:06:10 +02002339 truncate_restart_transaction(handle, inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002340 }
2341
Jan Karaf25f6242010-07-12 21:04:31 +02002342 /*
2343 * We've probably journalled the indirect block several
2344 * times during the truncate. But it's no longer
2345 * needed and we now drop it from the transaction via
2346 * journal_revoke().
2347 *
2348 * That's easy if it's exclusively part of this
2349 * transaction. But if it's part of the committing
2350 * transaction then journal_forget() will simply
2351 * brelse() it. That means that if the underlying
2352 * block is reallocated in ext3_get_block(),
2353 * unmap_underlying_metadata() will find this block
2354 * and will try to get rid of it. damn, damn. Thus
2355 * we don't allow a block to be reallocated until
2356 * a transaction freeing it has fully committed.
2357 *
2358 * We also have to make sure journal replay after a
2359 * crash does not overwrite non-journaled data blocks
2360 * with old metadata when the block got reallocated for
2361 * data. Thus we have to store a revoke record for a
2362 * block in the same transaction in which we free the
2363 * block.
2364 */
2365 ext3_forget(handle, 1, inode, bh, bh->b_blocknr);
2366
Linus Torvalds1da177e2005-04-16 15:20:36 -07002367 ext3_free_blocks(handle, inode, nr, 1);
2368
2369 if (parent_bh) {
2370 /*
2371 * The block which we have just freed is
2372 * pointed to by an indirect block: journal it
2373 */
2374 BUFFER_TRACE(parent_bh, "get_write_access");
2375 if (!ext3_journal_get_write_access(handle,
2376 parent_bh)){
2377 *p = 0;
2378 BUFFER_TRACE(parent_bh,
2379 "call ext3_journal_dirty_metadata");
Mingming Caoae6ddcc2006-09-27 01:49:27 -07002380 ext3_journal_dirty_metadata(handle,
Linus Torvalds1da177e2005-04-16 15:20:36 -07002381 parent_bh);
2382 }
2383 }
2384 }
2385 } else {
2386 /* We have reached the bottom of the tree. */
2387 BUFFER_TRACE(parent_bh, "free data blocks");
2388 ext3_free_data(handle, inode, parent_bh, first, last);
2389 }
2390}
2391
Duane Griffinae76dd92008-07-25 01:46:23 -07002392int ext3_can_truncate(struct inode *inode)
2393{
2394 if (IS_APPEND(inode) || IS_IMMUTABLE(inode))
2395 return 0;
2396 if (S_ISREG(inode->i_mode))
2397 return 1;
2398 if (S_ISDIR(inode->i_mode))
2399 return 1;
2400 if (S_ISLNK(inode->i_mode))
2401 return !ext3_inode_is_fast_symlink(inode);
2402 return 0;
2403}
2404
Linus Torvalds1da177e2005-04-16 15:20:36 -07002405/*
2406 * ext3_truncate()
2407 *
2408 * We block out ext3_get_block() block instantiations across the entire
2409 * transaction, and VFS/VM ensures that ext3_truncate() cannot run
2410 * simultaneously on behalf of the same inode.
2411 *
2412 * As we work through the truncate and commmit bits of it to the journal there
2413 * is one core, guiding principle: the file's tree must always be consistent on
2414 * disk. We must be able to restart the truncate after a crash.
2415 *
2416 * The file's tree may be transiently inconsistent in memory (although it
2417 * probably isn't), but whenever we close off and commit a journal transaction,
2418 * the contents of (the filesystem + the journal) must be consistent and
2419 * restartable. It's pretty simple, really: bottom up, right to left (although
2420 * left-to-right works OK too).
2421 *
2422 * Note that at recovery time, journal replay occurs *before* the restart of
2423 * truncate against the orphan inode list.
2424 *
2425 * The committed inode has the new, desired i_size (which is the same as
2426 * i_disksize in this case). After a crash, ext3_orphan_cleanup() will see
2427 * that this inode's truncate did not complete and it will again call
2428 * ext3_truncate() to have another go. So there will be instantiated blocks
2429 * to the right of the truncation point in a crashed ext3 filesystem. But
2430 * that's fine - as long as they are linked from the inode, the post-crash
2431 * ext3_truncate() run will find them and release them.
2432 */
Andrew Mortond6859bf2006-03-26 01:38:03 -08002433void ext3_truncate(struct inode *inode)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002434{
2435 handle_t *handle;
2436 struct ext3_inode_info *ei = EXT3_I(inode);
2437 __le32 *i_data = ei->i_data;
2438 int addr_per_block = EXT3_ADDR_PER_BLOCK(inode->i_sb);
2439 struct address_space *mapping = inode->i_mapping;
2440 int offsets[4];
2441 Indirect chain[4];
2442 Indirect *partial;
2443 __le32 nr = 0;
2444 int n;
2445 long last_block;
2446 unsigned blocksize = inode->i_sb->s_blocksize;
2447 struct page *page;
2448
Duane Griffinae76dd92008-07-25 01:46:23 -07002449 if (!ext3_can_truncate(inode))
Jan Karaef436182009-06-17 16:26:24 -07002450 goto out_notrans;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002451
Theodore Ts'of7ab34e2009-04-03 01:34:35 -04002452 if (inode->i_size == 0 && ext3_should_writeback_data(inode))
Jan Kara9df93932010-01-06 21:58:48 +01002453 ext3_set_inode_state(inode, EXT3_STATE_FLUSH_ON_CLOSE);
Theodore Ts'of7ab34e2009-04-03 01:34:35 -04002454
Linus Torvalds1da177e2005-04-16 15:20:36 -07002455 /*
2456 * We have to lock the EOF page here, because lock_page() nests
2457 * outside journal_start().
2458 */
2459 if ((inode->i_size & (blocksize - 1)) == 0) {
2460 /* Block boundary? Nothing to do */
2461 page = NULL;
2462 } else {
2463 page = grab_cache_page(mapping,
2464 inode->i_size >> PAGE_CACHE_SHIFT);
2465 if (!page)
Jan Karaef436182009-06-17 16:26:24 -07002466 goto out_notrans;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002467 }
2468
2469 handle = start_transaction(inode);
2470 if (IS_ERR(handle)) {
2471 if (page) {
2472 clear_highpage(page);
2473 flush_dcache_page(page);
2474 unlock_page(page);
2475 page_cache_release(page);
2476 }
Jan Karaef436182009-06-17 16:26:24 -07002477 goto out_notrans;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002478 }
2479
2480 last_block = (inode->i_size + blocksize-1)
2481 >> EXT3_BLOCK_SIZE_BITS(inode->i_sb);
2482
2483 if (page)
2484 ext3_block_truncate_page(handle, page, mapping, inode->i_size);
2485
2486 n = ext3_block_to_path(inode, last_block, offsets, NULL);
2487 if (n == 0)
2488 goto out_stop; /* error */
2489
2490 /*
2491 * OK. This truncate is going to happen. We add the inode to the
2492 * orphan list, so that if this truncate spans multiple transactions,
2493 * and we crash, we will resume the truncate when the filesystem
2494 * recovers. It also marks the inode dirty, to catch the new size.
2495 *
2496 * Implication: the file must always be in a sane, consistent
2497 * truncatable state while each transaction commits.
2498 */
2499 if (ext3_orphan_add(handle, inode))
2500 goto out_stop;
2501
2502 /*
2503 * The orphan list entry will now protect us from any crash which
2504 * occurs before the truncate completes, so it is now safe to propagate
2505 * the new, shorter inode size (held for now in i_size) into the
2506 * on-disk inode. We do this via i_disksize, which is the value which
2507 * ext3 *really* writes onto the disk inode.
2508 */
2509 ei->i_disksize = inode->i_size;
2510
2511 /*
2512 * From here we block out all ext3_get_block() callers who want to
2513 * modify the block allocation tree.
2514 */
Arjan van de Ven97461512006-03-23 03:00:42 -08002515 mutex_lock(&ei->truncate_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002516
2517 if (n == 1) { /* direct blocks */
2518 ext3_free_data(handle, inode, NULL, i_data+offsets[0],
2519 i_data + EXT3_NDIR_BLOCKS);
2520 goto do_indirects;
2521 }
2522
2523 partial = ext3_find_shared(inode, n, offsets, chain, &nr);
2524 /* Kill the top of shared branch (not detached) */
2525 if (nr) {
2526 if (partial == chain) {
2527 /* Shared branch grows from the inode */
2528 ext3_free_branches(handle, inode, NULL,
2529 &nr, &nr+1, (chain+n-1) - partial);
2530 *partial->p = 0;
2531 /*
2532 * We mark the inode dirty prior to restart,
2533 * and prior to stop. No need for it here.
2534 */
2535 } else {
2536 /* Shared branch grows from an indirect block */
Linus Torvalds1da177e2005-04-16 15:20:36 -07002537 ext3_free_branches(handle, inode, partial->bh,
2538 partial->p,
2539 partial->p+1, (chain+n-1) - partial);
2540 }
2541 }
2542 /* Clear the ends of indirect blocks on the shared branch */
2543 while (partial > chain) {
2544 ext3_free_branches(handle, inode, partial->bh, partial->p + 1,
2545 (__le32*)partial->bh->b_data+addr_per_block,
2546 (chain+n-1) - partial);
2547 BUFFER_TRACE(partial->bh, "call brelse");
2548 brelse (partial->bh);
2549 partial--;
2550 }
2551do_indirects:
2552 /* Kill the remaining (whole) subtrees */
2553 switch (offsets[0]) {
Andrew Mortond6859bf2006-03-26 01:38:03 -08002554 default:
2555 nr = i_data[EXT3_IND_BLOCK];
2556 if (nr) {
2557 ext3_free_branches(handle, inode, NULL, &nr, &nr+1, 1);
2558 i_data[EXT3_IND_BLOCK] = 0;
2559 }
2560 case EXT3_IND_BLOCK:
2561 nr = i_data[EXT3_DIND_BLOCK];
2562 if (nr) {
2563 ext3_free_branches(handle, inode, NULL, &nr, &nr+1, 2);
2564 i_data[EXT3_DIND_BLOCK] = 0;
2565 }
2566 case EXT3_DIND_BLOCK:
2567 nr = i_data[EXT3_TIND_BLOCK];
2568 if (nr) {
2569 ext3_free_branches(handle, inode, NULL, &nr, &nr+1, 3);
2570 i_data[EXT3_TIND_BLOCK] = 0;
2571 }
2572 case EXT3_TIND_BLOCK:
2573 ;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002574 }
2575
2576 ext3_discard_reservation(inode);
2577
Arjan van de Ven97461512006-03-23 03:00:42 -08002578 mutex_unlock(&ei->truncate_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002579 inode->i_mtime = inode->i_ctime = CURRENT_TIME_SEC;
2580 ext3_mark_inode_dirty(handle, inode);
2581
Andrew Mortond6859bf2006-03-26 01:38:03 -08002582 /*
2583 * In a multi-transaction truncate, we only make the final transaction
2584 * synchronous
2585 */
Linus Torvalds1da177e2005-04-16 15:20:36 -07002586 if (IS_SYNC(inode))
2587 handle->h_sync = 1;
2588out_stop:
2589 /*
2590 * If this was a simple ftruncate(), and the file will remain alive
2591 * then we need to clear up the orphan record which we created above.
2592 * However, if this was a real unlink then we were called by
Al Viroac14a952010-06-06 07:08:19 -04002593 * ext3_evict_inode(), and we allow that function to clean up the
Linus Torvalds1da177e2005-04-16 15:20:36 -07002594 * orphan info for us.
2595 */
2596 if (inode->i_nlink)
2597 ext3_orphan_del(handle, inode);
2598
2599 ext3_journal_stop(handle);
Jan Karaef436182009-06-17 16:26:24 -07002600 return;
2601out_notrans:
2602 /*
2603 * Delete the inode from orphan list so that it doesn't stay there
2604 * forever and trigger assertion on umount.
2605 */
2606 if (inode->i_nlink)
2607 ext3_orphan_del(NULL, inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002608}
2609
Mingming Cao43d23f92006-06-25 05:48:07 -07002610static ext3_fsblk_t ext3_get_inode_block(struct super_block *sb,
Linus Torvalds1da177e2005-04-16 15:20:36 -07002611 unsigned long ino, struct ext3_iloc *iloc)
2612{
Akinobu Mitae0e369a2008-04-28 02:16:08 -07002613 unsigned long block_group;
Mingming Cao43d23f92006-06-25 05:48:07 -07002614 unsigned long offset;
2615 ext3_fsblk_t block;
Akinobu Mitae0e369a2008-04-28 02:16:08 -07002616 struct ext3_group_desc *gdp;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002617
Neil Brown2ccb48e2006-07-30 03:03:01 -07002618 if (!ext3_valid_inum(sb, ino)) {
2619 /*
2620 * This error is already checked for in namei.c unless we are
2621 * looking at an NFS filehandle, in which case no error
2622 * report is needed
2623 */
Linus Torvalds1da177e2005-04-16 15:20:36 -07002624 return 0;
2625 }
Neil Brown2ccb48e2006-07-30 03:03:01 -07002626
Linus Torvalds1da177e2005-04-16 15:20:36 -07002627 block_group = (ino - 1) / EXT3_INODES_PER_GROUP(sb);
Akinobu Mitae0e369a2008-04-28 02:16:08 -07002628 gdp = ext3_get_group_desc(sb, block_group, NULL);
2629 if (!gdp)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002630 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002631 /*
2632 * Figure out the offset within the block group inode table
2633 */
2634 offset = ((ino - 1) % EXT3_INODES_PER_GROUP(sb)) *
2635 EXT3_INODE_SIZE(sb);
Akinobu Mitae0e369a2008-04-28 02:16:08 -07002636 block = le32_to_cpu(gdp->bg_inode_table) +
Linus Torvalds1da177e2005-04-16 15:20:36 -07002637 (offset >> EXT3_BLOCK_SIZE_BITS(sb));
2638
2639 iloc->block_group = block_group;
2640 iloc->offset = offset & (EXT3_BLOCK_SIZE(sb) - 1);
2641 return block;
2642}
2643
2644/*
2645 * ext3_get_inode_loc returns with an extra refcount against the inode's
2646 * underlying buffer_head on success. If 'in_mem' is true, we have all
2647 * data in memory that is needed to recreate the on-disk version of this
2648 * inode.
2649 */
2650static int __ext3_get_inode_loc(struct inode *inode,
2651 struct ext3_iloc *iloc, int in_mem)
2652{
Mingming Cao43d23f92006-06-25 05:48:07 -07002653 ext3_fsblk_t block;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002654 struct buffer_head *bh;
2655
2656 block = ext3_get_inode_block(inode->i_sb, inode->i_ino, iloc);
2657 if (!block)
2658 return -EIO;
2659
2660 bh = sb_getblk(inode->i_sb, block);
2661 if (!bh) {
2662 ext3_error (inode->i_sb, "ext3_get_inode_loc",
2663 "unable to read inode block - "
Mingming Cao43d23f92006-06-25 05:48:07 -07002664 "inode=%lu, block="E3FSBLK,
2665 inode->i_ino, block);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002666 return -EIO;
2667 }
2668 if (!buffer_uptodate(bh)) {
2669 lock_buffer(bh);
Hidehiro Kawai95450f52008-07-25 01:46:24 -07002670
2671 /*
2672 * If the buffer has the write error flag, we have failed
2673 * to write out another inode in the same block. In this
2674 * case, we don't have to read the block because we may
2675 * read the old inode data successfully.
2676 */
2677 if (buffer_write_io_error(bh) && !buffer_uptodate(bh))
2678 set_buffer_uptodate(bh);
2679
Linus Torvalds1da177e2005-04-16 15:20:36 -07002680 if (buffer_uptodate(bh)) {
2681 /* someone brought it uptodate while we waited */
2682 unlock_buffer(bh);
2683 goto has_buffer;
2684 }
2685
2686 /*
2687 * If we have all information of the inode in memory and this
2688 * is the only valid inode in the block, we need not read the
2689 * block.
2690 */
2691 if (in_mem) {
2692 struct buffer_head *bitmap_bh;
2693 struct ext3_group_desc *desc;
2694 int inodes_per_buffer;
2695 int inode_offset, i;
2696 int block_group;
2697 int start;
2698
2699 block_group = (inode->i_ino - 1) /
2700 EXT3_INODES_PER_GROUP(inode->i_sb);
2701 inodes_per_buffer = bh->b_size /
2702 EXT3_INODE_SIZE(inode->i_sb);
2703 inode_offset = ((inode->i_ino - 1) %
2704 EXT3_INODES_PER_GROUP(inode->i_sb));
2705 start = inode_offset & ~(inodes_per_buffer - 1);
2706
2707 /* Is the inode bitmap in cache? */
2708 desc = ext3_get_group_desc(inode->i_sb,
2709 block_group, NULL);
2710 if (!desc)
2711 goto make_io;
2712
2713 bitmap_bh = sb_getblk(inode->i_sb,
2714 le32_to_cpu(desc->bg_inode_bitmap));
2715 if (!bitmap_bh)
2716 goto make_io;
2717
2718 /*
2719 * If the inode bitmap isn't in cache then the
2720 * optimisation may end up performing two reads instead
2721 * of one, so skip it.
2722 */
2723 if (!buffer_uptodate(bitmap_bh)) {
2724 brelse(bitmap_bh);
2725 goto make_io;
2726 }
2727 for (i = start; i < start + inodes_per_buffer; i++) {
2728 if (i == inode_offset)
2729 continue;
2730 if (ext3_test_bit(i, bitmap_bh->b_data))
2731 break;
2732 }
2733 brelse(bitmap_bh);
2734 if (i == start + inodes_per_buffer) {
2735 /* all other inodes are free, so skip I/O */
2736 memset(bh->b_data, 0, bh->b_size);
2737 set_buffer_uptodate(bh);
2738 unlock_buffer(bh);
2739 goto has_buffer;
2740 }
2741 }
2742
2743make_io:
2744 /*
2745 * There are other valid inodes in the buffer, this inode
2746 * has in-inode xattrs, or we don't have this inode in memory.
2747 * Read the block from disk.
2748 */
2749 get_bh(bh);
2750 bh->b_end_io = end_buffer_read_sync;
Jens Axboecaa38fb2006-07-23 01:41:26 +02002751 submit_bh(READ_META, bh);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002752 wait_on_buffer(bh);
2753 if (!buffer_uptodate(bh)) {
2754 ext3_error(inode->i_sb, "ext3_get_inode_loc",
2755 "unable to read inode block - "
Mingming Cao43d23f92006-06-25 05:48:07 -07002756 "inode=%lu, block="E3FSBLK,
Linus Torvalds1da177e2005-04-16 15:20:36 -07002757 inode->i_ino, block);
2758 brelse(bh);
2759 return -EIO;
2760 }
2761 }
2762has_buffer:
2763 iloc->bh = bh;
2764 return 0;
2765}
2766
2767int ext3_get_inode_loc(struct inode *inode, struct ext3_iloc *iloc)
2768{
2769 /* We have all inode data except xattrs in memory here. */
2770 return __ext3_get_inode_loc(inode, iloc,
Jan Kara9df93932010-01-06 21:58:48 +01002771 !ext3_test_inode_state(inode, EXT3_STATE_XATTR));
Linus Torvalds1da177e2005-04-16 15:20:36 -07002772}
2773
2774void ext3_set_inode_flags(struct inode *inode)
2775{
2776 unsigned int flags = EXT3_I(inode)->i_flags;
2777
2778 inode->i_flags &= ~(S_SYNC|S_APPEND|S_IMMUTABLE|S_NOATIME|S_DIRSYNC);
2779 if (flags & EXT3_SYNC_FL)
2780 inode->i_flags |= S_SYNC;
2781 if (flags & EXT3_APPEND_FL)
2782 inode->i_flags |= S_APPEND;
2783 if (flags & EXT3_IMMUTABLE_FL)
2784 inode->i_flags |= S_IMMUTABLE;
2785 if (flags & EXT3_NOATIME_FL)
2786 inode->i_flags |= S_NOATIME;
2787 if (flags & EXT3_DIRSYNC_FL)
2788 inode->i_flags |= S_DIRSYNC;
2789}
2790
Jan Kara28be5ab2007-05-08 00:30:33 -07002791/* Propagate flags from i_flags to EXT3_I(inode)->i_flags */
2792void ext3_get_inode_flags(struct ext3_inode_info *ei)
2793{
2794 unsigned int flags = ei->vfs_inode.i_flags;
2795
2796 ei->i_flags &= ~(EXT3_SYNC_FL|EXT3_APPEND_FL|
2797 EXT3_IMMUTABLE_FL|EXT3_NOATIME_FL|EXT3_DIRSYNC_FL);
2798 if (flags & S_SYNC)
2799 ei->i_flags |= EXT3_SYNC_FL;
2800 if (flags & S_APPEND)
2801 ei->i_flags |= EXT3_APPEND_FL;
2802 if (flags & S_IMMUTABLE)
2803 ei->i_flags |= EXT3_IMMUTABLE_FL;
2804 if (flags & S_NOATIME)
2805 ei->i_flags |= EXT3_NOATIME_FL;
2806 if (flags & S_DIRSYNC)
2807 ei->i_flags |= EXT3_DIRSYNC_FL;
2808}
2809
David Howells473043d2008-02-07 00:15:36 -08002810struct inode *ext3_iget(struct super_block *sb, unsigned long ino)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002811{
2812 struct ext3_iloc iloc;
2813 struct ext3_inode *raw_inode;
David Howells473043d2008-02-07 00:15:36 -08002814 struct ext3_inode_info *ei;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002815 struct buffer_head *bh;
David Howells473043d2008-02-07 00:15:36 -08002816 struct inode *inode;
Jan Karafe8bc912009-10-16 19:26:15 +02002817 journal_t *journal = EXT3_SB(sb)->s_journal;
2818 transaction_t *transaction;
David Howells473043d2008-02-07 00:15:36 -08002819 long ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002820 int block;
2821
David Howells473043d2008-02-07 00:15:36 -08002822 inode = iget_locked(sb, ino);
2823 if (!inode)
2824 return ERR_PTR(-ENOMEM);
2825 if (!(inode->i_state & I_NEW))
2826 return inode;
2827
2828 ei = EXT3_I(inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002829 ei->i_block_alloc_info = NULL;
2830
David Howells473043d2008-02-07 00:15:36 -08002831 ret = __ext3_get_inode_loc(inode, &iloc, 0);
2832 if (ret < 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002833 goto bad_inode;
2834 bh = iloc.bh;
2835 raw_inode = ext3_raw_inode(&iloc);
2836 inode->i_mode = le16_to_cpu(raw_inode->i_mode);
2837 inode->i_uid = (uid_t)le16_to_cpu(raw_inode->i_uid_low);
2838 inode->i_gid = (gid_t)le16_to_cpu(raw_inode->i_gid_low);
2839 if(!(test_opt (inode->i_sb, NO_UID32))) {
2840 inode->i_uid |= le16_to_cpu(raw_inode->i_uid_high) << 16;
2841 inode->i_gid |= le16_to_cpu(raw_inode->i_gid_high) << 16;
2842 }
2843 inode->i_nlink = le16_to_cpu(raw_inode->i_links_count);
2844 inode->i_size = le32_to_cpu(raw_inode->i_size);
Markus Rechberger4d7bf112007-05-08 00:23:39 -07002845 inode->i_atime.tv_sec = (signed)le32_to_cpu(raw_inode->i_atime);
2846 inode->i_ctime.tv_sec = (signed)le32_to_cpu(raw_inode->i_ctime);
2847 inode->i_mtime.tv_sec = (signed)le32_to_cpu(raw_inode->i_mtime);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002848 inode->i_atime.tv_nsec = inode->i_ctime.tv_nsec = inode->i_mtime.tv_nsec = 0;
2849
Linus Torvaldsde329822010-03-29 14:30:19 -07002850 ei->i_state_flags = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002851 ei->i_dir_start_lookup = 0;
2852 ei->i_dtime = le32_to_cpu(raw_inode->i_dtime);
2853 /* We now have enough fields to check if the inode was active or not.
2854 * This is needed because nfsd might try to access dead inodes
2855 * the test is that same one that e2fsck uses
2856 * NeilBrown 1999oct15
2857 */
2858 if (inode->i_nlink == 0) {
2859 if (inode->i_mode == 0 ||
2860 !(EXT3_SB(inode->i_sb)->s_mount_state & EXT3_ORPHAN_FS)) {
2861 /* this inode is deleted */
2862 brelse (bh);
David Howells473043d2008-02-07 00:15:36 -08002863 ret = -ESTALE;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002864 goto bad_inode;
2865 }
2866 /* The only unlinked inodes we let through here have
2867 * valid i_mode and are being read by the orphan
2868 * recovery code: that's fine, we're about to complete
2869 * the process of deleting those. */
2870 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07002871 inode->i_blocks = le32_to_cpu(raw_inode->i_blocks);
2872 ei->i_flags = le32_to_cpu(raw_inode->i_flags);
2873#ifdef EXT3_FRAGMENTS
2874 ei->i_faddr = le32_to_cpu(raw_inode->i_faddr);
2875 ei->i_frag_no = raw_inode->i_frag;
2876 ei->i_frag_size = raw_inode->i_fsize;
2877#endif
2878 ei->i_file_acl = le32_to_cpu(raw_inode->i_file_acl);
2879 if (!S_ISREG(inode->i_mode)) {
2880 ei->i_dir_acl = le32_to_cpu(raw_inode->i_dir_acl);
2881 } else {
2882 inode->i_size |=
2883 ((__u64)le32_to_cpu(raw_inode->i_size_high)) << 32;
2884 }
2885 ei->i_disksize = inode->i_size;
2886 inode->i_generation = le32_to_cpu(raw_inode->i_generation);
2887 ei->i_block_group = iloc.block_group;
2888 /*
2889 * NOTE! The in-memory inode i_data array is in little-endian order
2890 * even on big-endian machines: we do NOT byteswap the block numbers!
2891 */
2892 for (block = 0; block < EXT3_N_BLOCKS; block++)
2893 ei->i_data[block] = raw_inode->i_block[block];
2894 INIT_LIST_HEAD(&ei->i_orphan);
2895
Jan Karafe8bc912009-10-16 19:26:15 +02002896 /*
2897 * Set transaction id's of transactions that have to be committed
2898 * to finish f[data]sync. We set them to currently running transaction
2899 * as we cannot be sure that the inode or some of its metadata isn't
2900 * part of the transaction - the inode could have been reclaimed and
2901 * now it is reread from disk.
2902 */
2903 if (journal) {
2904 tid_t tid;
2905
2906 spin_lock(&journal->j_state_lock);
2907 if (journal->j_running_transaction)
2908 transaction = journal->j_running_transaction;
2909 else
2910 transaction = journal->j_committing_transaction;
2911 if (transaction)
2912 tid = transaction->t_tid;
2913 else
2914 tid = journal->j_commit_sequence;
2915 spin_unlock(&journal->j_state_lock);
2916 atomic_set(&ei->i_sync_tid, tid);
2917 atomic_set(&ei->i_datasync_tid, tid);
2918 }
2919
Linus Torvalds1da177e2005-04-16 15:20:36 -07002920 if (inode->i_ino >= EXT3_FIRST_INO(inode->i_sb) + 1 &&
2921 EXT3_INODE_SIZE(inode->i_sb) > EXT3_GOOD_OLD_INODE_SIZE) {
2922 /*
2923 * When mke2fs creates big inodes it does not zero out
2924 * the unused bytes above EXT3_GOOD_OLD_INODE_SIZE,
2925 * so ignore those first few inodes.
2926 */
2927 ei->i_extra_isize = le16_to_cpu(raw_inode->i_extra_isize);
2928 if (EXT3_GOOD_OLD_INODE_SIZE + ei->i_extra_isize >
Kirill Korotaeve4a10a32007-06-23 17:16:48 -07002929 EXT3_INODE_SIZE(inode->i_sb)) {
2930 brelse (bh);
David Howells473043d2008-02-07 00:15:36 -08002931 ret = -EIO;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002932 goto bad_inode;
Kirill Korotaeve4a10a32007-06-23 17:16:48 -07002933 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07002934 if (ei->i_extra_isize == 0) {
2935 /* The extra space is currently unused. Use it. */
2936 ei->i_extra_isize = sizeof(struct ext3_inode) -
2937 EXT3_GOOD_OLD_INODE_SIZE;
2938 } else {
2939 __le32 *magic = (void *)raw_inode +
2940 EXT3_GOOD_OLD_INODE_SIZE +
2941 ei->i_extra_isize;
2942 if (*magic == cpu_to_le32(EXT3_XATTR_MAGIC))
Jan Kara9df93932010-01-06 21:58:48 +01002943 ext3_set_inode_state(inode, EXT3_STATE_XATTR);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002944 }
2945 } else
2946 ei->i_extra_isize = 0;
2947
2948 if (S_ISREG(inode->i_mode)) {
2949 inode->i_op = &ext3_file_inode_operations;
2950 inode->i_fop = &ext3_file_operations;
2951 ext3_set_aops(inode);
2952 } else if (S_ISDIR(inode->i_mode)) {
2953 inode->i_op = &ext3_dir_inode_operations;
2954 inode->i_fop = &ext3_dir_operations;
2955 } else if (S_ISLNK(inode->i_mode)) {
Duane Griffinb5ed3112008-12-19 20:47:14 +00002956 if (ext3_inode_is_fast_symlink(inode)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002957 inode->i_op = &ext3_fast_symlink_inode_operations;
Duane Griffinb5ed3112008-12-19 20:47:14 +00002958 nd_terminate_link(ei->i_data, inode->i_size,
2959 sizeof(ei->i_data) - 1);
2960 } else {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002961 inode->i_op = &ext3_symlink_inode_operations;
2962 ext3_set_aops(inode);
2963 }
2964 } else {
2965 inode->i_op = &ext3_special_inode_operations;
2966 if (raw_inode->i_block[0])
2967 init_special_inode(inode, inode->i_mode,
2968 old_decode_dev(le32_to_cpu(raw_inode->i_block[0])));
Mingming Caoae6ddcc2006-09-27 01:49:27 -07002969 else
Linus Torvalds1da177e2005-04-16 15:20:36 -07002970 init_special_inode(inode, inode->i_mode,
2971 new_decode_dev(le32_to_cpu(raw_inode->i_block[1])));
2972 }
2973 brelse (iloc.bh);
2974 ext3_set_inode_flags(inode);
David Howells473043d2008-02-07 00:15:36 -08002975 unlock_new_inode(inode);
2976 return inode;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002977
2978bad_inode:
David Howells473043d2008-02-07 00:15:36 -08002979 iget_failed(inode);
2980 return ERR_PTR(ret);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002981}
2982
2983/*
2984 * Post the struct inode info into an on-disk inode location in the
2985 * buffer-cache. This gobbles the caller's reference to the
2986 * buffer_head in the inode location struct.
2987 *
2988 * The caller must have write access to iloc->bh.
2989 */
Mingming Caoae6ddcc2006-09-27 01:49:27 -07002990static int ext3_do_update_inode(handle_t *handle,
2991 struct inode *inode,
Linus Torvalds1da177e2005-04-16 15:20:36 -07002992 struct ext3_iloc *iloc)
2993{
2994 struct ext3_inode *raw_inode = ext3_raw_inode(iloc);
2995 struct ext3_inode_info *ei = EXT3_I(inode);
2996 struct buffer_head *bh = iloc->bh;
2997 int err = 0, rc, block;
2998
Chris Mason4f003fd2009-09-08 00:22:14 +02002999again:
3000 /* we can't allow multiple procs in here at once, its a bit racey */
3001 lock_buffer(bh);
3002
Linus Torvalds1da177e2005-04-16 15:20:36 -07003003 /* For fields not not tracking in the in-memory inode,
3004 * initialise them to zero for new inodes. */
Jan Kara9df93932010-01-06 21:58:48 +01003005 if (ext3_test_inode_state(inode, EXT3_STATE_NEW))
Linus Torvalds1da177e2005-04-16 15:20:36 -07003006 memset(raw_inode, 0, EXT3_SB(inode->i_sb)->s_inode_size);
3007
Jan Kara28be5ab2007-05-08 00:30:33 -07003008 ext3_get_inode_flags(ei);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003009 raw_inode->i_mode = cpu_to_le16(inode->i_mode);
3010 if(!(test_opt(inode->i_sb, NO_UID32))) {
3011 raw_inode->i_uid_low = cpu_to_le16(low_16_bits(inode->i_uid));
3012 raw_inode->i_gid_low = cpu_to_le16(low_16_bits(inode->i_gid));
3013/*
3014 * Fix up interoperability with old kernels. Otherwise, old inodes get
3015 * re-used with the upper 16 bits of the uid/gid intact
3016 */
3017 if(!ei->i_dtime) {
3018 raw_inode->i_uid_high =
3019 cpu_to_le16(high_16_bits(inode->i_uid));
3020 raw_inode->i_gid_high =
3021 cpu_to_le16(high_16_bits(inode->i_gid));
3022 } else {
3023 raw_inode->i_uid_high = 0;
3024 raw_inode->i_gid_high = 0;
3025 }
3026 } else {
3027 raw_inode->i_uid_low =
3028 cpu_to_le16(fs_high2lowuid(inode->i_uid));
3029 raw_inode->i_gid_low =
3030 cpu_to_le16(fs_high2lowgid(inode->i_gid));
3031 raw_inode->i_uid_high = 0;
3032 raw_inode->i_gid_high = 0;
3033 }
3034 raw_inode->i_links_count = cpu_to_le16(inode->i_nlink);
3035 raw_inode->i_size = cpu_to_le32(ei->i_disksize);
3036 raw_inode->i_atime = cpu_to_le32(inode->i_atime.tv_sec);
3037 raw_inode->i_ctime = cpu_to_le32(inode->i_ctime.tv_sec);
3038 raw_inode->i_mtime = cpu_to_le32(inode->i_mtime.tv_sec);
3039 raw_inode->i_blocks = cpu_to_le32(inode->i_blocks);
3040 raw_inode->i_dtime = cpu_to_le32(ei->i_dtime);
3041 raw_inode->i_flags = cpu_to_le32(ei->i_flags);
3042#ifdef EXT3_FRAGMENTS
3043 raw_inode->i_faddr = cpu_to_le32(ei->i_faddr);
3044 raw_inode->i_frag = ei->i_frag_no;
3045 raw_inode->i_fsize = ei->i_frag_size;
3046#endif
3047 raw_inode->i_file_acl = cpu_to_le32(ei->i_file_acl);
3048 if (!S_ISREG(inode->i_mode)) {
3049 raw_inode->i_dir_acl = cpu_to_le32(ei->i_dir_acl);
3050 } else {
3051 raw_inode->i_size_high =
3052 cpu_to_le32(ei->i_disksize >> 32);
3053 if (ei->i_disksize > 0x7fffffffULL) {
3054 struct super_block *sb = inode->i_sb;
3055 if (!EXT3_HAS_RO_COMPAT_FEATURE(sb,
3056 EXT3_FEATURE_RO_COMPAT_LARGE_FILE) ||
3057 EXT3_SB(sb)->s_es->s_rev_level ==
3058 cpu_to_le32(EXT3_GOOD_OLD_REV)) {
3059 /* If this is the first large file
3060 * created, add a flag to the superblock.
3061 */
Chris Mason4f003fd2009-09-08 00:22:14 +02003062 unlock_buffer(bh);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003063 err = ext3_journal_get_write_access(handle,
3064 EXT3_SB(sb)->s_sbh);
3065 if (err)
3066 goto out_brelse;
Chris Mason4f003fd2009-09-08 00:22:14 +02003067
Linus Torvalds1da177e2005-04-16 15:20:36 -07003068 ext3_update_dynamic_rev(sb);
3069 EXT3_SET_RO_COMPAT_FEATURE(sb,
3070 EXT3_FEATURE_RO_COMPAT_LARGE_FILE);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003071 handle->h_sync = 1;
3072 err = ext3_journal_dirty_metadata(handle,
3073 EXT3_SB(sb)->s_sbh);
Chris Mason4f003fd2009-09-08 00:22:14 +02003074 /* get our lock and start over */
3075 goto again;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003076 }
3077 }
3078 }
3079 raw_inode->i_generation = cpu_to_le32(inode->i_generation);
3080 if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) {
3081 if (old_valid_dev(inode->i_rdev)) {
3082 raw_inode->i_block[0] =
3083 cpu_to_le32(old_encode_dev(inode->i_rdev));
3084 raw_inode->i_block[1] = 0;
3085 } else {
3086 raw_inode->i_block[0] = 0;
3087 raw_inode->i_block[1] =
3088 cpu_to_le32(new_encode_dev(inode->i_rdev));
3089 raw_inode->i_block[2] = 0;
3090 }
3091 } else for (block = 0; block < EXT3_N_BLOCKS; block++)
3092 raw_inode->i_block[block] = ei->i_data[block];
3093
Andreas Gruenbacherff87b372005-07-07 17:57:00 -07003094 if (ei->i_extra_isize)
Linus Torvalds1da177e2005-04-16 15:20:36 -07003095 raw_inode->i_extra_isize = cpu_to_le16(ei->i_extra_isize);
3096
3097 BUFFER_TRACE(bh, "call ext3_journal_dirty_metadata");
Chris Mason4f003fd2009-09-08 00:22:14 +02003098 unlock_buffer(bh);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003099 rc = ext3_journal_dirty_metadata(handle, bh);
3100 if (!err)
3101 err = rc;
Jan Kara9df93932010-01-06 21:58:48 +01003102 ext3_clear_inode_state(inode, EXT3_STATE_NEW);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003103
Jan Karafe8bc912009-10-16 19:26:15 +02003104 atomic_set(&ei->i_sync_tid, handle->h_transaction->t_tid);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003105out_brelse:
3106 brelse (bh);
3107 ext3_std_error(inode->i_sb, err);
3108 return err;
3109}
3110
3111/*
3112 * ext3_write_inode()
3113 *
3114 * We are called from a few places:
3115 *
3116 * - Within generic_file_write() for O_SYNC files.
3117 * Here, there will be no transaction running. We wait for any running
3118 * trasnaction to commit.
3119 *
3120 * - Within sys_sync(), kupdate and such.
3121 * We wait on commit, if tol to.
3122 *
3123 * - Within prune_icache() (PF_MEMALLOC == true)
3124 * Here we simply return. We can't afford to block kswapd on the
3125 * journal commit.
3126 *
3127 * In all cases it is actually safe for us to return without doing anything,
3128 * because the inode has been copied into a raw inode buffer in
3129 * ext3_mark_inode_dirty(). This is a correctness thing for O_SYNC and for
3130 * knfsd.
3131 *
3132 * Note that we are absolutely dependent upon all inode dirtiers doing the
3133 * right thing: they *must* call mark_inode_dirty() after dirtying info in
3134 * which we are interested.
3135 *
3136 * It would be a bug for them to not do this. The code:
3137 *
3138 * mark_inode_dirty(inode)
3139 * stuff();
3140 * inode->i_size = expr;
3141 *
3142 * is in error because a kswapd-driven write_inode() could occur while
3143 * `stuff()' is running, and the new i_size will be lost. Plus the inode
3144 * will no longer be on the superblock's dirty inode list.
3145 */
Christoph Hellwiga9185b42010-03-05 09:21:37 +01003146int ext3_write_inode(struct inode *inode, struct writeback_control *wbc)
Linus Torvalds1da177e2005-04-16 15:20:36 -07003147{
3148 if (current->flags & PF_MEMALLOC)
3149 return 0;
3150
3151 if (ext3_journal_current_handle()) {
Jose R. Santos9ad163a2007-10-18 23:39:23 -07003152 jbd_debug(1, "called recursively, non-PF_MEMALLOC!\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -07003153 dump_stack();
3154 return -EIO;
3155 }
3156
Christoph Hellwiga9185b42010-03-05 09:21:37 +01003157 if (wbc->sync_mode != WB_SYNC_ALL)
Linus Torvalds1da177e2005-04-16 15:20:36 -07003158 return 0;
3159
3160 return ext3_force_commit(inode->i_sb);
3161}
3162
3163/*
3164 * ext3_setattr()
3165 *
3166 * Called from notify_change.
3167 *
3168 * We want to trap VFS attempts to truncate the file as soon as
3169 * possible. In particular, we want to make sure that when the VFS
3170 * shrinks i_size, we put the inode on the orphan list and modify
3171 * i_disksize immediately, so that during the subsequent flushing of
3172 * dirty pages and freeing of disk blocks, we can guarantee that any
3173 * commit will leave the blocks being flushed in an unused state on
3174 * disk. (On recovery, the inode will get truncated and the blocks will
3175 * be freed, so we have a strong guarantee that no future commit will
Mingming Caoae6ddcc2006-09-27 01:49:27 -07003176 * leave these blocks visible to the user.)
Linus Torvalds1da177e2005-04-16 15:20:36 -07003177 *
3178 * Called with inode->sem down.
3179 */
3180int ext3_setattr(struct dentry *dentry, struct iattr *attr)
3181{
3182 struct inode *inode = dentry->d_inode;
3183 int error, rc = 0;
3184 const unsigned int ia_valid = attr->ia_valid;
3185
3186 error = inode_change_ok(inode, attr);
3187 if (error)
3188 return error;
3189
Dmitry Monakhov12755622010-04-08 22:04:20 +04003190 if (is_quota_modification(inode, attr))
Christoph Hellwig871a2932010-03-03 09:05:07 -05003191 dquot_initialize(inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003192 if ((ia_valid & ATTR_UID && attr->ia_uid != inode->i_uid) ||
3193 (ia_valid & ATTR_GID && attr->ia_gid != inode->i_gid)) {
3194 handle_t *handle;
3195
3196 /* (user+group)*(old+new) structure, inode write (sb,
3197 * inode block, ? - but truncate inode update has it) */
Dmitry Monakhovc4590012009-12-09 03:05:30 +03003198 handle = ext3_journal_start(inode, EXT3_MAXQUOTAS_INIT_BLOCKS(inode->i_sb)+
3199 EXT3_MAXQUOTAS_DEL_BLOCKS(inode->i_sb)+3);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003200 if (IS_ERR(handle)) {
3201 error = PTR_ERR(handle);
3202 goto err_out;
3203 }
Christoph Hellwigb43fa822010-03-03 09:05:03 -05003204 error = dquot_transfer(inode, attr);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003205 if (error) {
3206 ext3_journal_stop(handle);
3207 return error;
3208 }
3209 /* Update corresponding info in inode so that everything is in
3210 * one transaction */
3211 if (attr->ia_valid & ATTR_UID)
3212 inode->i_uid = attr->ia_uid;
3213 if (attr->ia_valid & ATTR_GID)
3214 inode->i_gid = attr->ia_gid;
3215 error = ext3_mark_inode_dirty(handle, inode);
3216 ext3_journal_stop(handle);
3217 }
3218
3219 if (S_ISREG(inode->i_mode) &&
3220 attr->ia_valid & ATTR_SIZE && attr->ia_size < inode->i_size) {
3221 handle_t *handle;
3222
3223 handle = ext3_journal_start(inode, 3);
3224 if (IS_ERR(handle)) {
3225 error = PTR_ERR(handle);
3226 goto err_out;
3227 }
3228
3229 error = ext3_orphan_add(handle, inode);
3230 EXT3_I(inode)->i_disksize = attr->ia_size;
3231 rc = ext3_mark_inode_dirty(handle, inode);
3232 if (!error)
3233 error = rc;
3234 ext3_journal_stop(handle);
3235 }
3236
Christoph Hellwig10257742010-06-04 11:30:02 +02003237 if ((attr->ia_valid & ATTR_SIZE) &&
3238 attr->ia_size != i_size_read(inode)) {
3239 rc = vmtruncate(inode, attr->ia_size);
3240 if (rc)
3241 goto err_out;
3242 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07003243
Christoph Hellwig10257742010-06-04 11:30:02 +02003244 setattr_copy(inode, attr);
3245 mark_inode_dirty(inode);
3246
3247 if (ia_valid & ATTR_MODE)
Linus Torvalds1da177e2005-04-16 15:20:36 -07003248 rc = ext3_acl_chmod(inode);
3249
3250err_out:
3251 ext3_std_error(inode->i_sb, error);
3252 if (!error)
3253 error = rc;
3254 return error;
3255}
3256
3257
3258/*
Andrew Mortond6859bf2006-03-26 01:38:03 -08003259 * How many blocks doth make a writepage()?
Linus Torvalds1da177e2005-04-16 15:20:36 -07003260 *
3261 * With N blocks per page, it may be:
3262 * N data blocks
3263 * 2 indirect block
3264 * 2 dindirect
3265 * 1 tindirect
3266 * N+5 bitmap blocks (from the above)
3267 * N+5 group descriptor summary blocks
3268 * 1 inode block
3269 * 1 superblock.
3270 * 2 * EXT3_SINGLEDATA_TRANS_BLOCKS for the quote files
3271 *
3272 * 3 * (N + 5) + 2 + 2 * EXT3_SINGLEDATA_TRANS_BLOCKS
3273 *
3274 * With ordered or writeback data it's the same, less the N data blocks.
3275 *
3276 * If the inode's direct blocks can hold an integral number of pages then a
3277 * page cannot straddle two indirect blocks, and we can only touch one indirect
3278 * and dindirect block, and the "5" above becomes "3".
3279 *
3280 * This still overestimates under most circumstances. If we were to pass the
3281 * start and end offsets in here as well we could do block_to_path() on each
3282 * block and work out the exact number of indirects which are touched. Pah.
3283 */
3284
3285static int ext3_writepage_trans_blocks(struct inode *inode)
3286{
3287 int bpp = ext3_journal_blocks_per_page(inode);
3288 int indirects = (EXT3_NDIR_BLOCKS % bpp) ? 5 : 3;
3289 int ret;
3290
3291 if (ext3_should_journal_data(inode))
3292 ret = 3 * (bpp + indirects) + 2;
3293 else
Yongqiang Yang523334b2011-03-24 08:48:39 +08003294 ret = 2 * (bpp + indirects) + indirects + 2;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003295
3296#ifdef CONFIG_QUOTA
Christoph Hellwig871a2932010-03-03 09:05:07 -05003297 /* We know that structure was already allocated during dquot_initialize so
Linus Torvalds1da177e2005-04-16 15:20:36 -07003298 * we will be updating only the data blocks + inodes */
Dmitry Monakhovc4590012009-12-09 03:05:30 +03003299 ret += EXT3_MAXQUOTAS_TRANS_BLOCKS(inode->i_sb);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003300#endif
3301
3302 return ret;
3303}
3304
3305/*
3306 * The caller must have previously called ext3_reserve_inode_write().
3307 * Give this, we know that the caller already has write access to iloc->bh.
3308 */
3309int ext3_mark_iloc_dirty(handle_t *handle,
3310 struct inode *inode, struct ext3_iloc *iloc)
3311{
3312 int err = 0;
3313
3314 /* the do_update_inode consumes one bh->b_count */
3315 get_bh(iloc->bh);
3316
3317 /* ext3_do_update_inode() does journal_dirty_metadata */
3318 err = ext3_do_update_inode(handle, inode, iloc);
3319 put_bh(iloc->bh);
3320 return err;
3321}
3322
Mingming Caoae6ddcc2006-09-27 01:49:27 -07003323/*
Linus Torvalds1da177e2005-04-16 15:20:36 -07003324 * On success, We end up with an outstanding reference count against
Mingming Caoae6ddcc2006-09-27 01:49:27 -07003325 * iloc->bh. This _must_ be cleaned up later.
Linus Torvalds1da177e2005-04-16 15:20:36 -07003326 */
3327
3328int
Mingming Caoae6ddcc2006-09-27 01:49:27 -07003329ext3_reserve_inode_write(handle_t *handle, struct inode *inode,
Linus Torvalds1da177e2005-04-16 15:20:36 -07003330 struct ext3_iloc *iloc)
3331{
3332 int err = 0;
3333 if (handle) {
3334 err = ext3_get_inode_loc(inode, iloc);
3335 if (!err) {
3336 BUFFER_TRACE(iloc->bh, "get_write_access");
3337 err = ext3_journal_get_write_access(handle, iloc->bh);
3338 if (err) {
3339 brelse(iloc->bh);
3340 iloc->bh = NULL;
3341 }
3342 }
3343 }
3344 ext3_std_error(inode->i_sb, err);
3345 return err;
3346}
3347
3348/*
Andrew Mortond6859bf2006-03-26 01:38:03 -08003349 * What we do here is to mark the in-core inode as clean with respect to inode
3350 * dirtiness (it may still be data-dirty).
Linus Torvalds1da177e2005-04-16 15:20:36 -07003351 * This means that the in-core inode may be reaped by prune_icache
3352 * without having to perform any I/O. This is a very good thing,
3353 * because *any* task may call prune_icache - even ones which
3354 * have a transaction open against a different journal.
3355 *
3356 * Is this cheating? Not really. Sure, we haven't written the
3357 * inode out, but prune_icache isn't a user-visible syncing function.
3358 * Whenever the user wants stuff synced (sys_sync, sys_msync, sys_fsync)
3359 * we start and wait on commits.
3360 *
3361 * Is this efficient/effective? Well, we're being nice to the system
3362 * by cleaning up our inodes proactively so they can be reaped
3363 * without I/O. But we are potentially leaving up to five seconds'
3364 * worth of inodes floating about which prune_icache wants us to
3365 * write out. One way to fix that would be to get prune_icache()
3366 * to do a write_super() to free up some memory. It has the desired
3367 * effect.
3368 */
3369int ext3_mark_inode_dirty(handle_t *handle, struct inode *inode)
3370{
3371 struct ext3_iloc iloc;
3372 int err;
3373
3374 might_sleep();
3375 err = ext3_reserve_inode_write(handle, inode, &iloc);
3376 if (!err)
3377 err = ext3_mark_iloc_dirty(handle, inode, &iloc);
3378 return err;
3379}
3380
3381/*
Andrew Mortond6859bf2006-03-26 01:38:03 -08003382 * ext3_dirty_inode() is called from __mark_inode_dirty()
Linus Torvalds1da177e2005-04-16 15:20:36 -07003383 *
3384 * We're really interested in the case where a file is being extended.
3385 * i_size has been changed by generic_commit_write() and we thus need
3386 * to include the updated inode in the current transaction.
3387 *
Christoph Hellwig5dd40562010-03-03 09:05:00 -05003388 * Also, dquot_alloc_space() will always dirty the inode when blocks
Linus Torvalds1da177e2005-04-16 15:20:36 -07003389 * are allocated to the file.
3390 *
3391 * If the inode is marked synchronous, we don't honour that here - doing
3392 * so would cause a commit on atime updates, which we don't bother doing.
3393 * We handle synchronous inodes at the highest possible level.
3394 */
Christoph Hellwigaa385722011-05-27 06:53:02 -04003395void ext3_dirty_inode(struct inode *inode, int flags)
Linus Torvalds1da177e2005-04-16 15:20:36 -07003396{
3397 handle_t *current_handle = ext3_journal_current_handle();
3398 handle_t *handle;
3399
3400 handle = ext3_journal_start(inode, 2);
3401 if (IS_ERR(handle))
3402 goto out;
3403 if (current_handle &&
3404 current_handle->h_transaction != handle->h_transaction) {
3405 /* This task has a transaction open against a different fs */
3406 printk(KERN_EMERG "%s: transactions do not match!\n",
Harvey Harrisone05b6b52008-04-28 02:16:15 -07003407 __func__);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003408 } else {
3409 jbd_debug(5, "marking dirty. outer handle=%p\n",
3410 current_handle);
3411 ext3_mark_inode_dirty(handle, inode);
3412 }
3413 ext3_journal_stop(handle);
3414out:
3415 return;
3416}
3417
Andrew Mortond6859bf2006-03-26 01:38:03 -08003418#if 0
Mingming Caoae6ddcc2006-09-27 01:49:27 -07003419/*
Linus Torvalds1da177e2005-04-16 15:20:36 -07003420 * Bind an inode's backing buffer_head into this transaction, to prevent
3421 * it from being flushed to disk early. Unlike
3422 * ext3_reserve_inode_write, this leaves behind no bh reference and
3423 * returns no iloc structure, so the caller needs to repeat the iloc
3424 * lookup to mark the inode dirty later.
3425 */
Andrew Mortond6859bf2006-03-26 01:38:03 -08003426static int ext3_pin_inode(handle_t *handle, struct inode *inode)
Linus Torvalds1da177e2005-04-16 15:20:36 -07003427{
3428 struct ext3_iloc iloc;
3429
3430 int err = 0;
3431 if (handle) {
3432 err = ext3_get_inode_loc(inode, &iloc);
3433 if (!err) {
3434 BUFFER_TRACE(iloc.bh, "get_write_access");
3435 err = journal_get_write_access(handle, iloc.bh);
3436 if (!err)
Mingming Caoae6ddcc2006-09-27 01:49:27 -07003437 err = ext3_journal_dirty_metadata(handle,
Linus Torvalds1da177e2005-04-16 15:20:36 -07003438 iloc.bh);
3439 brelse(iloc.bh);
3440 }
3441 }
3442 ext3_std_error(inode->i_sb, err);
3443 return err;
3444}
3445#endif
3446
3447int ext3_change_inode_journal_flag(struct inode *inode, int val)
3448{
3449 journal_t *journal;
3450 handle_t *handle;
3451 int err;
3452
3453 /*
3454 * We have to be very careful here: changing a data block's
3455 * journaling status dynamically is dangerous. If we write a
3456 * data block to the journal, change the status and then delete
3457 * that block, we risk forgetting to revoke the old log record
3458 * from the journal and so a subsequent replay can corrupt data.
3459 * So, first we make sure that the journal is empty and that
3460 * nobody is changing anything.
3461 */
3462
3463 journal = EXT3_JOURNAL(inode);
Dave Hansene3a68e32007-07-15 23:41:14 -07003464 if (is_journal_aborted(journal))
Linus Torvalds1da177e2005-04-16 15:20:36 -07003465 return -EROFS;
3466
3467 journal_lock_updates(journal);
3468 journal_flush(journal);
3469
3470 /*
3471 * OK, there are no updates running now, and all cached data is
3472 * synced to disk. We are now in a completely consistent state
3473 * which doesn't have anything in the journal, and we know that
3474 * no filesystem updates are running, so it is safe to modify
3475 * the inode's in-core data-journaling state flag now.
3476 */
3477
3478 if (val)
3479 EXT3_I(inode)->i_flags |= EXT3_JOURNAL_DATA_FL;
3480 else
3481 EXT3_I(inode)->i_flags &= ~EXT3_JOURNAL_DATA_FL;
3482 ext3_set_aops(inode);
3483
3484 journal_unlock_updates(journal);
3485
3486 /* Finally we can mark the inode as dirty. */
3487
3488 handle = ext3_journal_start(inode, 1);
3489 if (IS_ERR(handle))
3490 return PTR_ERR(handle);
3491
3492 err = ext3_mark_inode_dirty(handle, inode);
3493 handle->h_sync = 1;
3494 ext3_journal_stop(handle);
3495 ext3_std_error(inode->i_sb, err);
3496
3497 return err;
3498}