blob: ae94f6d949f526d04fc0e2dcb8983622eeab8fa0 [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 Boissinot1cc8dcf52008-04-21 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 Boissinot1cc8dcf52008-04-21 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 Boissinot1cc8dcf52008-04-21 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,
1897 .sync_page = block_sync_page,
1898 .write_begin = ext3_write_begin,
1899 .write_end = ext3_ordered_write_end,
1900 .bmap = ext3_bmap,
1901 .invalidatepage = ext3_invalidatepage,
1902 .releasepage = ext3_releasepage,
1903 .direct_IO = ext3_direct_IO,
1904 .migratepage = buffer_migrate_page,
1905 .is_partially_uptodate = block_is_partially_uptodate,
Andi Kleenaa261f52009-09-16 11:50:16 +02001906 .error_remove_page = generic_error_remove_page,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001907};
1908
Christoph Hellwigf5e54d62006-06-28 04:26:44 -07001909static const struct address_space_operations ext3_writeback_aops = {
Hisashi Hifumi8ab22b92008-07-28 15:46:36 -07001910 .readpage = ext3_readpage,
1911 .readpages = ext3_readpages,
1912 .writepage = ext3_writeback_writepage,
1913 .sync_page = block_sync_page,
1914 .write_begin = ext3_write_begin,
1915 .write_end = ext3_writeback_write_end,
1916 .bmap = ext3_bmap,
1917 .invalidatepage = ext3_invalidatepage,
1918 .releasepage = ext3_releasepage,
1919 .direct_IO = ext3_direct_IO,
1920 .migratepage = buffer_migrate_page,
1921 .is_partially_uptodate = block_is_partially_uptodate,
Andi Kleenaa261f52009-09-16 11:50:16 +02001922 .error_remove_page = generic_error_remove_page,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001923};
1924
Christoph Hellwigf5e54d62006-06-28 04:26:44 -07001925static const struct address_space_operations ext3_journalled_aops = {
Hisashi Hifumi8ab22b92008-07-28 15:46:36 -07001926 .readpage = ext3_readpage,
1927 .readpages = ext3_readpages,
1928 .writepage = ext3_journalled_writepage,
1929 .sync_page = block_sync_page,
1930 .write_begin = ext3_write_begin,
1931 .write_end = ext3_journalled_write_end,
1932 .set_page_dirty = ext3_journalled_set_page_dirty,
1933 .bmap = ext3_bmap,
1934 .invalidatepage = ext3_invalidatepage,
1935 .releasepage = ext3_releasepage,
1936 .is_partially_uptodate = block_is_partially_uptodate,
Andi Kleenaa261f52009-09-16 11:50:16 +02001937 .error_remove_page = generic_error_remove_page,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001938};
1939
1940void ext3_set_aops(struct inode *inode)
1941{
1942 if (ext3_should_order_data(inode))
1943 inode->i_mapping->a_ops = &ext3_ordered_aops;
1944 else if (ext3_should_writeback_data(inode))
1945 inode->i_mapping->a_ops = &ext3_writeback_aops;
1946 else
1947 inode->i_mapping->a_ops = &ext3_journalled_aops;
1948}
1949
1950/*
1951 * ext3_block_truncate_page() zeroes out a mapping from file offset `from'
1952 * up to the end of the block which corresponds to `from'.
1953 * This required during truncate. We need to physically zero the tail end
1954 * of that block so it doesn't yield old data if the file is later grown.
1955 */
1956static int ext3_block_truncate_page(handle_t *handle, struct page *page,
1957 struct address_space *mapping, loff_t from)
1958{
Mingming Cao43d23f92006-06-25 05:48:07 -07001959 ext3_fsblk_t index = from >> PAGE_CACHE_SHIFT;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001960 unsigned offset = from & (PAGE_CACHE_SIZE-1);
1961 unsigned blocksize, iblock, length, pos;
1962 struct inode *inode = mapping->host;
1963 struct buffer_head *bh;
1964 int err = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001965
1966 blocksize = inode->i_sb->s_blocksize;
1967 length = blocksize - (offset & (blocksize - 1));
1968 iblock = index << (PAGE_CACHE_SHIFT - inode->i_sb->s_blocksize_bits);
1969
Linus Torvalds1da177e2005-04-16 15:20:36 -07001970 if (!page_has_buffers(page))
1971 create_empty_buffers(page, blocksize, 0);
1972
1973 /* Find the buffer that contains "offset" */
1974 bh = page_buffers(page);
1975 pos = blocksize;
1976 while (offset >= pos) {
1977 bh = bh->b_this_page;
1978 iblock++;
1979 pos += blocksize;
1980 }
1981
1982 err = 0;
1983 if (buffer_freed(bh)) {
1984 BUFFER_TRACE(bh, "freed: skip");
1985 goto unlock;
1986 }
1987
1988 if (!buffer_mapped(bh)) {
1989 BUFFER_TRACE(bh, "unmapped");
1990 ext3_get_block(inode, iblock, bh, 0);
1991 /* unmapped? It's a hole - nothing to do */
1992 if (!buffer_mapped(bh)) {
1993 BUFFER_TRACE(bh, "still unmapped");
1994 goto unlock;
1995 }
1996 }
1997
1998 /* Ok, it's mapped. Make sure it's up-to-date */
1999 if (PageUptodate(page))
2000 set_buffer_uptodate(bh);
2001
2002 if (!buffer_uptodate(bh)) {
2003 err = -EIO;
2004 ll_rw_block(READ, 1, &bh);
2005 wait_on_buffer(bh);
2006 /* Uhhuh. Read error. Complain and punt. */
2007 if (!buffer_uptodate(bh))
2008 goto unlock;
2009 }
2010
2011 if (ext3_should_journal_data(inode)) {
2012 BUFFER_TRACE(bh, "get write access");
2013 err = ext3_journal_get_write_access(handle, bh);
2014 if (err)
2015 goto unlock;
2016 }
2017
Christoph Lametereebd2aa2008-02-04 22:28:29 -08002018 zero_user(page, offset, length);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002019 BUFFER_TRACE(bh, "zeroed end of block");
2020
2021 err = 0;
2022 if (ext3_should_journal_data(inode)) {
2023 err = ext3_journal_dirty_metadata(handle, bh);
2024 } else {
2025 if (ext3_should_order_data(inode))
2026 err = ext3_journal_dirty_data(handle, bh);
2027 mark_buffer_dirty(bh);
2028 }
2029
2030unlock:
2031 unlock_page(page);
2032 page_cache_release(page);
2033 return err;
2034}
2035
2036/*
2037 * Probably it should be a library function... search for first non-zero word
2038 * or memcmp with zero_page, whatever is better for particular architecture.
2039 * Linus?
2040 */
2041static inline int all_zeroes(__le32 *p, __le32 *q)
2042{
2043 while (p < q)
2044 if (*p++)
2045 return 0;
2046 return 1;
2047}
2048
2049/**
2050 * ext3_find_shared - find the indirect blocks for partial truncation.
2051 * @inode: inode in question
2052 * @depth: depth of the affected branch
2053 * @offsets: offsets of pointers in that branch (see ext3_block_to_path)
2054 * @chain: place to store the pointers to partial indirect blocks
2055 * @top: place to the (detached) top of branch
2056 *
2057 * This is a helper function used by ext3_truncate().
2058 *
2059 * When we do truncate() we may have to clean the ends of several
2060 * indirect blocks but leave the blocks themselves alive. Block is
2061 * partially truncated if some data below the new i_size is refered
2062 * from it (and it is on the path to the first completely truncated
2063 * data block, indeed). We have to free the top of that path along
2064 * with everything to the right of the path. Since no allocation
2065 * past the truncation point is possible until ext3_truncate()
2066 * finishes, we may safely do the latter, but top of branch may
2067 * require special attention - pageout below the truncation point
2068 * might try to populate it.
2069 *
2070 * We atomically detach the top of branch from the tree, store the
2071 * block number of its root in *@top, pointers to buffer_heads of
2072 * partially truncated blocks - in @chain[].bh and pointers to
2073 * their last elements that should not be removed - in
2074 * @chain[].p. Return value is the pointer to last filled element
2075 * of @chain.
2076 *
2077 * The work left to caller to do the actual freeing of subtrees:
2078 * a) free the subtree starting from *@top
2079 * b) free the subtrees whose roots are stored in
2080 * (@chain[i].p+1 .. end of @chain[i].bh->b_data)
2081 * c) free the subtrees growing from the inode past the @chain[0].
2082 * (no partially truncated stuff there). */
2083
Andrew Mortond6859bf2006-03-26 01:38:03 -08002084static Indirect *ext3_find_shared(struct inode *inode, int depth,
2085 int offsets[4], Indirect chain[4], __le32 *top)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002086{
2087 Indirect *partial, *p;
2088 int k, err;
2089
2090 *top = 0;
Uwe Kleine-Königbf48aab2009-10-28 20:11:03 +01002091 /* Make k index the deepest non-null offset + 1 */
Linus Torvalds1da177e2005-04-16 15:20:36 -07002092 for (k = depth; k > 1 && !offsets[k-1]; k--)
2093 ;
2094 partial = ext3_get_branch(inode, k, offsets, chain, &err);
2095 /* Writer: pointers */
2096 if (!partial)
2097 partial = chain + k-1;
2098 /*
2099 * If the branch acquired continuation since we've looked at it -
2100 * fine, it should all survive and (new) top doesn't belong to us.
2101 */
2102 if (!partial->key && *partial->p)
2103 /* Writer: end */
2104 goto no_top;
2105 for (p=partial; p>chain && all_zeroes((__le32*)p->bh->b_data,p->p); p--)
2106 ;
2107 /*
2108 * OK, we've found the last block that must survive. The rest of our
2109 * branch should be detached before unlocking. However, if that rest
2110 * of branch is all ours and does not grow immediately from the inode
2111 * it's easier to cheat and just decrement partial->p.
2112 */
2113 if (p == chain + k - 1 && p > chain) {
2114 p->p--;
2115 } else {
2116 *top = *p->p;
2117 /* Nope, don't do this in ext3. Must leave the tree intact */
2118#if 0
2119 *p->p = 0;
2120#endif
2121 }
2122 /* Writer: end */
2123
Andrew Mortond6859bf2006-03-26 01:38:03 -08002124 while(partial > p) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002125 brelse(partial->bh);
2126 partial--;
2127 }
2128no_top:
2129 return partial;
2130}
2131
2132/*
2133 * Zero a number of block pointers in either an inode or an indirect block.
2134 * If we restart the transaction we must again get write access to the
2135 * indirect block for further modification.
2136 *
2137 * We release `count' blocks on disk, but (last - first) may be greater
2138 * than `count' because there can be holes in there.
2139 */
Andrew Mortond6859bf2006-03-26 01:38:03 -08002140static void ext3_clear_blocks(handle_t *handle, struct inode *inode,
Mingming Cao43d23f92006-06-25 05:48:07 -07002141 struct buffer_head *bh, ext3_fsblk_t block_to_free,
Andrew Mortond6859bf2006-03-26 01:38:03 -08002142 unsigned long count, __le32 *first, __le32 *last)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002143{
2144 __le32 *p;
2145 if (try_to_extend_transaction(handle, inode)) {
2146 if (bh) {
2147 BUFFER_TRACE(bh, "call ext3_journal_dirty_metadata");
Namhyung Kim156e7432010-11-25 01:53:13 +09002148 if (ext3_journal_dirty_metadata(handle, bh))
2149 return;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002150 }
2151 ext3_mark_inode_dirty(handle, inode);
Jan Kara00171d32009-08-11 19:06:10 +02002152 truncate_restart_transaction(handle, inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002153 if (bh) {
2154 BUFFER_TRACE(bh, "retaking write access");
Namhyung Kim156e7432010-11-25 01:53:13 +09002155 if (ext3_journal_get_write_access(handle, bh))
2156 return;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002157 }
2158 }
2159
2160 /*
2161 * Any buffers which are on the journal will be in memory. We find
2162 * them on the hash table so journal_revoke() will run journal_forget()
2163 * on them. We've already detached each block from the file, so
2164 * bforget() in journal_forget() should be safe.
2165 *
2166 * AKPM: turn on bforget in journal_forget()!!!
2167 */
2168 for (p = first; p < last; p++) {
2169 u32 nr = le32_to_cpu(*p);
2170 if (nr) {
2171 struct buffer_head *bh;
2172
2173 *p = 0;
2174 bh = sb_find_get_block(inode->i_sb, nr);
2175 ext3_forget(handle, 0, inode, bh, nr);
2176 }
2177 }
2178
2179 ext3_free_blocks(handle, inode, block_to_free, count);
2180}
2181
2182/**
2183 * ext3_free_data - free a list of data blocks
2184 * @handle: handle for this transaction
2185 * @inode: inode we are dealing with
2186 * @this_bh: indirect buffer_head which contains *@first and *@last
2187 * @first: array of block numbers
2188 * @last: points immediately past the end of array
2189 *
2190 * We are freeing all blocks refered from that array (numbers are stored as
2191 * little-endian 32-bit) and updating @inode->i_blocks appropriately.
2192 *
2193 * We accumulate contiguous runs of blocks to free. Conveniently, if these
2194 * blocks are contiguous then releasing them at one time will only affect one
2195 * or two bitmap blocks (+ group descriptor(s) and superblock) and we won't
2196 * actually use a lot of journal space.
2197 *
2198 * @this_bh will be %NULL if @first and @last point into the inode's direct
2199 * block pointers.
2200 */
2201static void ext3_free_data(handle_t *handle, struct inode *inode,
2202 struct buffer_head *this_bh,
2203 __le32 *first, __le32 *last)
2204{
Mingming Cao43d23f92006-06-25 05:48:07 -07002205 ext3_fsblk_t block_to_free = 0; /* Starting block # of a run */
Mingming Caoae6ddcc2006-09-27 01:49:27 -07002206 unsigned long count = 0; /* Number of blocks in the run */
Linus Torvalds1da177e2005-04-16 15:20:36 -07002207 __le32 *block_to_free_p = NULL; /* Pointer into inode/ind
2208 corresponding to
2209 block_to_free */
Mingming Cao43d23f92006-06-25 05:48:07 -07002210 ext3_fsblk_t nr; /* Current block # */
Linus Torvalds1da177e2005-04-16 15:20:36 -07002211 __le32 *p; /* Pointer into inode/ind
2212 for current block */
2213 int err;
2214
2215 if (this_bh) { /* For indirect block */
2216 BUFFER_TRACE(this_bh, "get_write_access");
2217 err = ext3_journal_get_write_access(handle, this_bh);
2218 /* Important: if we can't update the indirect pointers
2219 * to the blocks, we can't free them. */
2220 if (err)
2221 return;
2222 }
2223
2224 for (p = first; p < last; p++) {
2225 nr = le32_to_cpu(*p);
2226 if (nr) {
2227 /* accumulate blocks to free if they're contiguous */
2228 if (count == 0) {
2229 block_to_free = nr;
2230 block_to_free_p = p;
2231 count = 1;
2232 } else if (nr == block_to_free + count) {
2233 count++;
2234 } else {
Mingming Caoae6ddcc2006-09-27 01:49:27 -07002235 ext3_clear_blocks(handle, inode, this_bh,
Linus Torvalds1da177e2005-04-16 15:20:36 -07002236 block_to_free,
2237 count, block_to_free_p, p);
2238 block_to_free = nr;
2239 block_to_free_p = p;
2240 count = 1;
2241 }
2242 }
2243 }
2244
2245 if (count > 0)
2246 ext3_clear_blocks(handle, inode, this_bh, block_to_free,
2247 count, block_to_free_p, p);
2248
2249 if (this_bh) {
2250 BUFFER_TRACE(this_bh, "call ext3_journal_dirty_metadata");
Duane Griffin3ccc3162008-07-25 01:46:26 -07002251
2252 /*
2253 * The buffer head should have an attached journal head at this
2254 * point. However, if the data is corrupted and an indirect
2255 * block pointed to itself, it would have been detached when
2256 * the block was cleared. Check for this instead of OOPSing.
2257 */
2258 if (bh2jh(this_bh))
2259 ext3_journal_dirty_metadata(handle, this_bh);
2260 else
2261 ext3_error(inode->i_sb, "ext3_free_data",
2262 "circular indirect block detected, "
2263 "inode=%lu, block=%llu",
2264 inode->i_ino,
2265 (unsigned long long)this_bh->b_blocknr);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002266 }
2267}
2268
2269/**
2270 * ext3_free_branches - free an array of branches
2271 * @handle: JBD handle for this transaction
2272 * @inode: inode we are dealing with
2273 * @parent_bh: the buffer_head which contains *@first and *@last
2274 * @first: array of block numbers
2275 * @last: pointer immediately past the end of array
2276 * @depth: depth of the branches to free
2277 *
2278 * We are freeing all blocks refered from these branches (numbers are
2279 * stored as little-endian 32-bit) and updating @inode->i_blocks
2280 * appropriately.
2281 */
2282static void ext3_free_branches(handle_t *handle, struct inode *inode,
2283 struct buffer_head *parent_bh,
2284 __le32 *first, __le32 *last, int depth)
2285{
Mingming Cao43d23f92006-06-25 05:48:07 -07002286 ext3_fsblk_t nr;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002287 __le32 *p;
2288
2289 if (is_handle_aborted(handle))
2290 return;
2291
2292 if (depth--) {
2293 struct buffer_head *bh;
2294 int addr_per_block = EXT3_ADDR_PER_BLOCK(inode->i_sb);
2295 p = last;
2296 while (--p >= first) {
2297 nr = le32_to_cpu(*p);
2298 if (!nr)
2299 continue; /* A hole */
2300
2301 /* Go read the buffer for the next level down */
2302 bh = sb_bread(inode->i_sb, nr);
2303
2304 /*
2305 * A read failure? Report error and clear slot
2306 * (should be rare).
2307 */
2308 if (!bh) {
2309 ext3_error(inode->i_sb, "ext3_free_branches",
Eric Sandeeneee194e2006-09-27 01:49:30 -07002310 "Read failure, inode=%lu, block="E3FSBLK,
Linus Torvalds1da177e2005-04-16 15:20:36 -07002311 inode->i_ino, nr);
2312 continue;
2313 }
2314
2315 /* This zaps the entire block. Bottom up. */
2316 BUFFER_TRACE(bh, "free child branches");
2317 ext3_free_branches(handle, inode, bh,
2318 (__le32*)bh->b_data,
2319 (__le32*)bh->b_data + addr_per_block,
2320 depth);
2321
2322 /*
Linus Torvalds1da177e2005-04-16 15:20:36 -07002323 * Everything below this this pointer has been
2324 * released. Now let this top-of-subtree go.
2325 *
2326 * We want the freeing of this indirect block to be
2327 * atomic in the journal with the updating of the
2328 * bitmap block which owns it. So make some room in
2329 * the journal.
2330 *
2331 * We zero the parent pointer *after* freeing its
2332 * pointee in the bitmaps, so if extend_transaction()
2333 * for some reason fails to put the bitmap changes and
2334 * the release into the same transaction, recovery
2335 * will merely complain about releasing a free block,
2336 * rather than leaking blocks.
2337 */
2338 if (is_handle_aborted(handle))
2339 return;
2340 if (try_to_extend_transaction(handle, inode)) {
2341 ext3_mark_inode_dirty(handle, inode);
Jan Kara00171d32009-08-11 19:06:10 +02002342 truncate_restart_transaction(handle, inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002343 }
2344
Jan Karaf25f6242010-07-12 21:04:31 +02002345 /*
2346 * We've probably journalled the indirect block several
2347 * times during the truncate. But it's no longer
2348 * needed and we now drop it from the transaction via
2349 * journal_revoke().
2350 *
2351 * That's easy if it's exclusively part of this
2352 * transaction. But if it's part of the committing
2353 * transaction then journal_forget() will simply
2354 * brelse() it. That means that if the underlying
2355 * block is reallocated in ext3_get_block(),
2356 * unmap_underlying_metadata() will find this block
2357 * and will try to get rid of it. damn, damn. Thus
2358 * we don't allow a block to be reallocated until
2359 * a transaction freeing it has fully committed.
2360 *
2361 * We also have to make sure journal replay after a
2362 * crash does not overwrite non-journaled data blocks
2363 * with old metadata when the block got reallocated for
2364 * data. Thus we have to store a revoke record for a
2365 * block in the same transaction in which we free the
2366 * block.
2367 */
2368 ext3_forget(handle, 1, inode, bh, bh->b_blocknr);
2369
Linus Torvalds1da177e2005-04-16 15:20:36 -07002370 ext3_free_blocks(handle, inode, nr, 1);
2371
2372 if (parent_bh) {
2373 /*
2374 * The block which we have just freed is
2375 * pointed to by an indirect block: journal it
2376 */
2377 BUFFER_TRACE(parent_bh, "get_write_access");
2378 if (!ext3_journal_get_write_access(handle,
2379 parent_bh)){
2380 *p = 0;
2381 BUFFER_TRACE(parent_bh,
2382 "call ext3_journal_dirty_metadata");
Mingming Caoae6ddcc2006-09-27 01:49:27 -07002383 ext3_journal_dirty_metadata(handle,
Linus Torvalds1da177e2005-04-16 15:20:36 -07002384 parent_bh);
2385 }
2386 }
2387 }
2388 } else {
2389 /* We have reached the bottom of the tree. */
2390 BUFFER_TRACE(parent_bh, "free data blocks");
2391 ext3_free_data(handle, inode, parent_bh, first, last);
2392 }
2393}
2394
Duane Griffinae76dd92008-07-25 01:46:23 -07002395int ext3_can_truncate(struct inode *inode)
2396{
2397 if (IS_APPEND(inode) || IS_IMMUTABLE(inode))
2398 return 0;
2399 if (S_ISREG(inode->i_mode))
2400 return 1;
2401 if (S_ISDIR(inode->i_mode))
2402 return 1;
2403 if (S_ISLNK(inode->i_mode))
2404 return !ext3_inode_is_fast_symlink(inode);
2405 return 0;
2406}
2407
Linus Torvalds1da177e2005-04-16 15:20:36 -07002408/*
2409 * ext3_truncate()
2410 *
2411 * We block out ext3_get_block() block instantiations across the entire
2412 * transaction, and VFS/VM ensures that ext3_truncate() cannot run
2413 * simultaneously on behalf of the same inode.
2414 *
2415 * As we work through the truncate and commmit bits of it to the journal there
2416 * is one core, guiding principle: the file's tree must always be consistent on
2417 * disk. We must be able to restart the truncate after a crash.
2418 *
2419 * The file's tree may be transiently inconsistent in memory (although it
2420 * probably isn't), but whenever we close off and commit a journal transaction,
2421 * the contents of (the filesystem + the journal) must be consistent and
2422 * restartable. It's pretty simple, really: bottom up, right to left (although
2423 * left-to-right works OK too).
2424 *
2425 * Note that at recovery time, journal replay occurs *before* the restart of
2426 * truncate against the orphan inode list.
2427 *
2428 * The committed inode has the new, desired i_size (which is the same as
2429 * i_disksize in this case). After a crash, ext3_orphan_cleanup() will see
2430 * that this inode's truncate did not complete and it will again call
2431 * ext3_truncate() to have another go. So there will be instantiated blocks
2432 * to the right of the truncation point in a crashed ext3 filesystem. But
2433 * that's fine - as long as they are linked from the inode, the post-crash
2434 * ext3_truncate() run will find them and release them.
2435 */
Andrew Mortond6859bf2006-03-26 01:38:03 -08002436void ext3_truncate(struct inode *inode)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002437{
2438 handle_t *handle;
2439 struct ext3_inode_info *ei = EXT3_I(inode);
2440 __le32 *i_data = ei->i_data;
2441 int addr_per_block = EXT3_ADDR_PER_BLOCK(inode->i_sb);
2442 struct address_space *mapping = inode->i_mapping;
2443 int offsets[4];
2444 Indirect chain[4];
2445 Indirect *partial;
2446 __le32 nr = 0;
2447 int n;
2448 long last_block;
2449 unsigned blocksize = inode->i_sb->s_blocksize;
2450 struct page *page;
2451
Duane Griffinae76dd92008-07-25 01:46:23 -07002452 if (!ext3_can_truncate(inode))
Jan Karaef436182009-06-17 16:26:24 -07002453 goto out_notrans;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002454
Theodore Ts'of7ab34e2009-04-03 01:34:35 -04002455 if (inode->i_size == 0 && ext3_should_writeback_data(inode))
Jan Kara9df93932010-01-06 21:58:48 +01002456 ext3_set_inode_state(inode, EXT3_STATE_FLUSH_ON_CLOSE);
Theodore Ts'of7ab34e2009-04-03 01:34:35 -04002457
Linus Torvalds1da177e2005-04-16 15:20:36 -07002458 /*
2459 * We have to lock the EOF page here, because lock_page() nests
2460 * outside journal_start().
2461 */
2462 if ((inode->i_size & (blocksize - 1)) == 0) {
2463 /* Block boundary? Nothing to do */
2464 page = NULL;
2465 } else {
2466 page = grab_cache_page(mapping,
2467 inode->i_size >> PAGE_CACHE_SHIFT);
2468 if (!page)
Jan Karaef436182009-06-17 16:26:24 -07002469 goto out_notrans;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002470 }
2471
2472 handle = start_transaction(inode);
2473 if (IS_ERR(handle)) {
2474 if (page) {
2475 clear_highpage(page);
2476 flush_dcache_page(page);
2477 unlock_page(page);
2478 page_cache_release(page);
2479 }
Jan Karaef436182009-06-17 16:26:24 -07002480 goto out_notrans;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002481 }
2482
2483 last_block = (inode->i_size + blocksize-1)
2484 >> EXT3_BLOCK_SIZE_BITS(inode->i_sb);
2485
2486 if (page)
2487 ext3_block_truncate_page(handle, page, mapping, inode->i_size);
2488
2489 n = ext3_block_to_path(inode, last_block, offsets, NULL);
2490 if (n == 0)
2491 goto out_stop; /* error */
2492
2493 /*
2494 * OK. This truncate is going to happen. We add the inode to the
2495 * orphan list, so that if this truncate spans multiple transactions,
2496 * and we crash, we will resume the truncate when the filesystem
2497 * recovers. It also marks the inode dirty, to catch the new size.
2498 *
2499 * Implication: the file must always be in a sane, consistent
2500 * truncatable state while each transaction commits.
2501 */
2502 if (ext3_orphan_add(handle, inode))
2503 goto out_stop;
2504
2505 /*
2506 * The orphan list entry will now protect us from any crash which
2507 * occurs before the truncate completes, so it is now safe to propagate
2508 * the new, shorter inode size (held for now in i_size) into the
2509 * on-disk inode. We do this via i_disksize, which is the value which
2510 * ext3 *really* writes onto the disk inode.
2511 */
2512 ei->i_disksize = inode->i_size;
2513
2514 /*
2515 * From here we block out all ext3_get_block() callers who want to
2516 * modify the block allocation tree.
2517 */
Arjan van de Ven97461512006-03-23 03:00:42 -08002518 mutex_lock(&ei->truncate_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002519
2520 if (n == 1) { /* direct blocks */
2521 ext3_free_data(handle, inode, NULL, i_data+offsets[0],
2522 i_data + EXT3_NDIR_BLOCKS);
2523 goto do_indirects;
2524 }
2525
2526 partial = ext3_find_shared(inode, n, offsets, chain, &nr);
2527 /* Kill the top of shared branch (not detached) */
2528 if (nr) {
2529 if (partial == chain) {
2530 /* Shared branch grows from the inode */
2531 ext3_free_branches(handle, inode, NULL,
2532 &nr, &nr+1, (chain+n-1) - partial);
2533 *partial->p = 0;
2534 /*
2535 * We mark the inode dirty prior to restart,
2536 * and prior to stop. No need for it here.
2537 */
2538 } else {
2539 /* Shared branch grows from an indirect block */
Linus Torvalds1da177e2005-04-16 15:20:36 -07002540 ext3_free_branches(handle, inode, partial->bh,
2541 partial->p,
2542 partial->p+1, (chain+n-1) - partial);
2543 }
2544 }
2545 /* Clear the ends of indirect blocks on the shared branch */
2546 while (partial > chain) {
2547 ext3_free_branches(handle, inode, partial->bh, partial->p + 1,
2548 (__le32*)partial->bh->b_data+addr_per_block,
2549 (chain+n-1) - partial);
2550 BUFFER_TRACE(partial->bh, "call brelse");
2551 brelse (partial->bh);
2552 partial--;
2553 }
2554do_indirects:
2555 /* Kill the remaining (whole) subtrees */
2556 switch (offsets[0]) {
Andrew Mortond6859bf2006-03-26 01:38:03 -08002557 default:
2558 nr = i_data[EXT3_IND_BLOCK];
2559 if (nr) {
2560 ext3_free_branches(handle, inode, NULL, &nr, &nr+1, 1);
2561 i_data[EXT3_IND_BLOCK] = 0;
2562 }
2563 case EXT3_IND_BLOCK:
2564 nr = i_data[EXT3_DIND_BLOCK];
2565 if (nr) {
2566 ext3_free_branches(handle, inode, NULL, &nr, &nr+1, 2);
2567 i_data[EXT3_DIND_BLOCK] = 0;
2568 }
2569 case EXT3_DIND_BLOCK:
2570 nr = i_data[EXT3_TIND_BLOCK];
2571 if (nr) {
2572 ext3_free_branches(handle, inode, NULL, &nr, &nr+1, 3);
2573 i_data[EXT3_TIND_BLOCK] = 0;
2574 }
2575 case EXT3_TIND_BLOCK:
2576 ;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002577 }
2578
2579 ext3_discard_reservation(inode);
2580
Arjan van de Ven97461512006-03-23 03:00:42 -08002581 mutex_unlock(&ei->truncate_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002582 inode->i_mtime = inode->i_ctime = CURRENT_TIME_SEC;
2583 ext3_mark_inode_dirty(handle, inode);
2584
Andrew Mortond6859bf2006-03-26 01:38:03 -08002585 /*
2586 * In a multi-transaction truncate, we only make the final transaction
2587 * synchronous
2588 */
Linus Torvalds1da177e2005-04-16 15:20:36 -07002589 if (IS_SYNC(inode))
2590 handle->h_sync = 1;
2591out_stop:
2592 /*
2593 * If this was a simple ftruncate(), and the file will remain alive
2594 * then we need to clear up the orphan record which we created above.
2595 * However, if this was a real unlink then we were called by
Al Viroac14a952010-06-06 07:08:19 -04002596 * ext3_evict_inode(), and we allow that function to clean up the
Linus Torvalds1da177e2005-04-16 15:20:36 -07002597 * orphan info for us.
2598 */
2599 if (inode->i_nlink)
2600 ext3_orphan_del(handle, inode);
2601
2602 ext3_journal_stop(handle);
Jan Karaef436182009-06-17 16:26:24 -07002603 return;
2604out_notrans:
2605 /*
2606 * Delete the inode from orphan list so that it doesn't stay there
2607 * forever and trigger assertion on umount.
2608 */
2609 if (inode->i_nlink)
2610 ext3_orphan_del(NULL, inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002611}
2612
Mingming Cao43d23f92006-06-25 05:48:07 -07002613static ext3_fsblk_t ext3_get_inode_block(struct super_block *sb,
Linus Torvalds1da177e2005-04-16 15:20:36 -07002614 unsigned long ino, struct ext3_iloc *iloc)
2615{
Akinobu Mitae0e369a2008-04-28 02:16:08 -07002616 unsigned long block_group;
Mingming Cao43d23f92006-06-25 05:48:07 -07002617 unsigned long offset;
2618 ext3_fsblk_t block;
Akinobu Mitae0e369a2008-04-28 02:16:08 -07002619 struct ext3_group_desc *gdp;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002620
Neil Brown2ccb48e2006-07-30 03:03:01 -07002621 if (!ext3_valid_inum(sb, ino)) {
2622 /*
2623 * This error is already checked for in namei.c unless we are
2624 * looking at an NFS filehandle, in which case no error
2625 * report is needed
2626 */
Linus Torvalds1da177e2005-04-16 15:20:36 -07002627 return 0;
2628 }
Neil Brown2ccb48e2006-07-30 03:03:01 -07002629
Linus Torvalds1da177e2005-04-16 15:20:36 -07002630 block_group = (ino - 1) / EXT3_INODES_PER_GROUP(sb);
Akinobu Mitae0e369a2008-04-28 02:16:08 -07002631 gdp = ext3_get_group_desc(sb, block_group, NULL);
2632 if (!gdp)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002633 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002634 /*
2635 * Figure out the offset within the block group inode table
2636 */
2637 offset = ((ino - 1) % EXT3_INODES_PER_GROUP(sb)) *
2638 EXT3_INODE_SIZE(sb);
Akinobu Mitae0e369a2008-04-28 02:16:08 -07002639 block = le32_to_cpu(gdp->bg_inode_table) +
Linus Torvalds1da177e2005-04-16 15:20:36 -07002640 (offset >> EXT3_BLOCK_SIZE_BITS(sb));
2641
2642 iloc->block_group = block_group;
2643 iloc->offset = offset & (EXT3_BLOCK_SIZE(sb) - 1);
2644 return block;
2645}
2646
2647/*
2648 * ext3_get_inode_loc returns with an extra refcount against the inode's
2649 * underlying buffer_head on success. If 'in_mem' is true, we have all
2650 * data in memory that is needed to recreate the on-disk version of this
2651 * inode.
2652 */
2653static int __ext3_get_inode_loc(struct inode *inode,
2654 struct ext3_iloc *iloc, int in_mem)
2655{
Mingming Cao43d23f92006-06-25 05:48:07 -07002656 ext3_fsblk_t block;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002657 struct buffer_head *bh;
2658
2659 block = ext3_get_inode_block(inode->i_sb, inode->i_ino, iloc);
2660 if (!block)
2661 return -EIO;
2662
2663 bh = sb_getblk(inode->i_sb, block);
2664 if (!bh) {
2665 ext3_error (inode->i_sb, "ext3_get_inode_loc",
2666 "unable to read inode block - "
Mingming Cao43d23f92006-06-25 05:48:07 -07002667 "inode=%lu, block="E3FSBLK,
2668 inode->i_ino, block);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002669 return -EIO;
2670 }
2671 if (!buffer_uptodate(bh)) {
2672 lock_buffer(bh);
Hidehiro Kawai95450f52008-07-25 01:46:24 -07002673
2674 /*
2675 * If the buffer has the write error flag, we have failed
2676 * to write out another inode in the same block. In this
2677 * case, we don't have to read the block because we may
2678 * read the old inode data successfully.
2679 */
2680 if (buffer_write_io_error(bh) && !buffer_uptodate(bh))
2681 set_buffer_uptodate(bh);
2682
Linus Torvalds1da177e2005-04-16 15:20:36 -07002683 if (buffer_uptodate(bh)) {
2684 /* someone brought it uptodate while we waited */
2685 unlock_buffer(bh);
2686 goto has_buffer;
2687 }
2688
2689 /*
2690 * If we have all information of the inode in memory and this
2691 * is the only valid inode in the block, we need not read the
2692 * block.
2693 */
2694 if (in_mem) {
2695 struct buffer_head *bitmap_bh;
2696 struct ext3_group_desc *desc;
2697 int inodes_per_buffer;
2698 int inode_offset, i;
2699 int block_group;
2700 int start;
2701
2702 block_group = (inode->i_ino - 1) /
2703 EXT3_INODES_PER_GROUP(inode->i_sb);
2704 inodes_per_buffer = bh->b_size /
2705 EXT3_INODE_SIZE(inode->i_sb);
2706 inode_offset = ((inode->i_ino - 1) %
2707 EXT3_INODES_PER_GROUP(inode->i_sb));
2708 start = inode_offset & ~(inodes_per_buffer - 1);
2709
2710 /* Is the inode bitmap in cache? */
2711 desc = ext3_get_group_desc(inode->i_sb,
2712 block_group, NULL);
2713 if (!desc)
2714 goto make_io;
2715
2716 bitmap_bh = sb_getblk(inode->i_sb,
2717 le32_to_cpu(desc->bg_inode_bitmap));
2718 if (!bitmap_bh)
2719 goto make_io;
2720
2721 /*
2722 * If the inode bitmap isn't in cache then the
2723 * optimisation may end up performing two reads instead
2724 * of one, so skip it.
2725 */
2726 if (!buffer_uptodate(bitmap_bh)) {
2727 brelse(bitmap_bh);
2728 goto make_io;
2729 }
2730 for (i = start; i < start + inodes_per_buffer; i++) {
2731 if (i == inode_offset)
2732 continue;
2733 if (ext3_test_bit(i, bitmap_bh->b_data))
2734 break;
2735 }
2736 brelse(bitmap_bh);
2737 if (i == start + inodes_per_buffer) {
2738 /* all other inodes are free, so skip I/O */
2739 memset(bh->b_data, 0, bh->b_size);
2740 set_buffer_uptodate(bh);
2741 unlock_buffer(bh);
2742 goto has_buffer;
2743 }
2744 }
2745
2746make_io:
2747 /*
2748 * There are other valid inodes in the buffer, this inode
2749 * has in-inode xattrs, or we don't have this inode in memory.
2750 * Read the block from disk.
2751 */
2752 get_bh(bh);
2753 bh->b_end_io = end_buffer_read_sync;
Jens Axboecaa38fb2006-07-23 01:41:26 +02002754 submit_bh(READ_META, bh);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002755 wait_on_buffer(bh);
2756 if (!buffer_uptodate(bh)) {
2757 ext3_error(inode->i_sb, "ext3_get_inode_loc",
2758 "unable to read inode block - "
Mingming Cao43d23f92006-06-25 05:48:07 -07002759 "inode=%lu, block="E3FSBLK,
Linus Torvalds1da177e2005-04-16 15:20:36 -07002760 inode->i_ino, block);
2761 brelse(bh);
2762 return -EIO;
2763 }
2764 }
2765has_buffer:
2766 iloc->bh = bh;
2767 return 0;
2768}
2769
2770int ext3_get_inode_loc(struct inode *inode, struct ext3_iloc *iloc)
2771{
2772 /* We have all inode data except xattrs in memory here. */
2773 return __ext3_get_inode_loc(inode, iloc,
Jan Kara9df93932010-01-06 21:58:48 +01002774 !ext3_test_inode_state(inode, EXT3_STATE_XATTR));
Linus Torvalds1da177e2005-04-16 15:20:36 -07002775}
2776
2777void ext3_set_inode_flags(struct inode *inode)
2778{
2779 unsigned int flags = EXT3_I(inode)->i_flags;
2780
2781 inode->i_flags &= ~(S_SYNC|S_APPEND|S_IMMUTABLE|S_NOATIME|S_DIRSYNC);
2782 if (flags & EXT3_SYNC_FL)
2783 inode->i_flags |= S_SYNC;
2784 if (flags & EXT3_APPEND_FL)
2785 inode->i_flags |= S_APPEND;
2786 if (flags & EXT3_IMMUTABLE_FL)
2787 inode->i_flags |= S_IMMUTABLE;
2788 if (flags & EXT3_NOATIME_FL)
2789 inode->i_flags |= S_NOATIME;
2790 if (flags & EXT3_DIRSYNC_FL)
2791 inode->i_flags |= S_DIRSYNC;
2792}
2793
Jan Kara28be5ab2007-05-08 00:30:33 -07002794/* Propagate flags from i_flags to EXT3_I(inode)->i_flags */
2795void ext3_get_inode_flags(struct ext3_inode_info *ei)
2796{
2797 unsigned int flags = ei->vfs_inode.i_flags;
2798
2799 ei->i_flags &= ~(EXT3_SYNC_FL|EXT3_APPEND_FL|
2800 EXT3_IMMUTABLE_FL|EXT3_NOATIME_FL|EXT3_DIRSYNC_FL);
2801 if (flags & S_SYNC)
2802 ei->i_flags |= EXT3_SYNC_FL;
2803 if (flags & S_APPEND)
2804 ei->i_flags |= EXT3_APPEND_FL;
2805 if (flags & S_IMMUTABLE)
2806 ei->i_flags |= EXT3_IMMUTABLE_FL;
2807 if (flags & S_NOATIME)
2808 ei->i_flags |= EXT3_NOATIME_FL;
2809 if (flags & S_DIRSYNC)
2810 ei->i_flags |= EXT3_DIRSYNC_FL;
2811}
2812
David Howells473043d2008-02-07 00:15:36 -08002813struct inode *ext3_iget(struct super_block *sb, unsigned long ino)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002814{
2815 struct ext3_iloc iloc;
2816 struct ext3_inode *raw_inode;
David Howells473043d2008-02-07 00:15:36 -08002817 struct ext3_inode_info *ei;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002818 struct buffer_head *bh;
David Howells473043d2008-02-07 00:15:36 -08002819 struct inode *inode;
Jan Karafe8bc912009-10-16 19:26:15 +02002820 journal_t *journal = EXT3_SB(sb)->s_journal;
2821 transaction_t *transaction;
David Howells473043d2008-02-07 00:15:36 -08002822 long ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002823 int block;
2824
David Howells473043d2008-02-07 00:15:36 -08002825 inode = iget_locked(sb, ino);
2826 if (!inode)
2827 return ERR_PTR(-ENOMEM);
2828 if (!(inode->i_state & I_NEW))
2829 return inode;
2830
2831 ei = EXT3_I(inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002832 ei->i_block_alloc_info = NULL;
2833
David Howells473043d2008-02-07 00:15:36 -08002834 ret = __ext3_get_inode_loc(inode, &iloc, 0);
2835 if (ret < 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002836 goto bad_inode;
2837 bh = iloc.bh;
2838 raw_inode = ext3_raw_inode(&iloc);
2839 inode->i_mode = le16_to_cpu(raw_inode->i_mode);
2840 inode->i_uid = (uid_t)le16_to_cpu(raw_inode->i_uid_low);
2841 inode->i_gid = (gid_t)le16_to_cpu(raw_inode->i_gid_low);
2842 if(!(test_opt (inode->i_sb, NO_UID32))) {
2843 inode->i_uid |= le16_to_cpu(raw_inode->i_uid_high) << 16;
2844 inode->i_gid |= le16_to_cpu(raw_inode->i_gid_high) << 16;
2845 }
2846 inode->i_nlink = le16_to_cpu(raw_inode->i_links_count);
2847 inode->i_size = le32_to_cpu(raw_inode->i_size);
Markus Rechberger4d7bf112007-05-08 00:23:39 -07002848 inode->i_atime.tv_sec = (signed)le32_to_cpu(raw_inode->i_atime);
2849 inode->i_ctime.tv_sec = (signed)le32_to_cpu(raw_inode->i_ctime);
2850 inode->i_mtime.tv_sec = (signed)le32_to_cpu(raw_inode->i_mtime);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002851 inode->i_atime.tv_nsec = inode->i_ctime.tv_nsec = inode->i_mtime.tv_nsec = 0;
2852
Linus Torvaldsde329822010-03-29 14:30:19 -07002853 ei->i_state_flags = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002854 ei->i_dir_start_lookup = 0;
2855 ei->i_dtime = le32_to_cpu(raw_inode->i_dtime);
2856 /* We now have enough fields to check if the inode was active or not.
2857 * This is needed because nfsd might try to access dead inodes
2858 * the test is that same one that e2fsck uses
2859 * NeilBrown 1999oct15
2860 */
2861 if (inode->i_nlink == 0) {
2862 if (inode->i_mode == 0 ||
2863 !(EXT3_SB(inode->i_sb)->s_mount_state & EXT3_ORPHAN_FS)) {
2864 /* this inode is deleted */
2865 brelse (bh);
David Howells473043d2008-02-07 00:15:36 -08002866 ret = -ESTALE;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002867 goto bad_inode;
2868 }
2869 /* The only unlinked inodes we let through here have
2870 * valid i_mode and are being read by the orphan
2871 * recovery code: that's fine, we're about to complete
2872 * the process of deleting those. */
2873 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07002874 inode->i_blocks = le32_to_cpu(raw_inode->i_blocks);
2875 ei->i_flags = le32_to_cpu(raw_inode->i_flags);
2876#ifdef EXT3_FRAGMENTS
2877 ei->i_faddr = le32_to_cpu(raw_inode->i_faddr);
2878 ei->i_frag_no = raw_inode->i_frag;
2879 ei->i_frag_size = raw_inode->i_fsize;
2880#endif
2881 ei->i_file_acl = le32_to_cpu(raw_inode->i_file_acl);
2882 if (!S_ISREG(inode->i_mode)) {
2883 ei->i_dir_acl = le32_to_cpu(raw_inode->i_dir_acl);
2884 } else {
2885 inode->i_size |=
2886 ((__u64)le32_to_cpu(raw_inode->i_size_high)) << 32;
2887 }
2888 ei->i_disksize = inode->i_size;
2889 inode->i_generation = le32_to_cpu(raw_inode->i_generation);
2890 ei->i_block_group = iloc.block_group;
2891 /*
2892 * NOTE! The in-memory inode i_data array is in little-endian order
2893 * even on big-endian machines: we do NOT byteswap the block numbers!
2894 */
2895 for (block = 0; block < EXT3_N_BLOCKS; block++)
2896 ei->i_data[block] = raw_inode->i_block[block];
2897 INIT_LIST_HEAD(&ei->i_orphan);
2898
Jan Karafe8bc912009-10-16 19:26:15 +02002899 /*
2900 * Set transaction id's of transactions that have to be committed
2901 * to finish f[data]sync. We set them to currently running transaction
2902 * as we cannot be sure that the inode or some of its metadata isn't
2903 * part of the transaction - the inode could have been reclaimed and
2904 * now it is reread from disk.
2905 */
2906 if (journal) {
2907 tid_t tid;
2908
2909 spin_lock(&journal->j_state_lock);
2910 if (journal->j_running_transaction)
2911 transaction = journal->j_running_transaction;
2912 else
2913 transaction = journal->j_committing_transaction;
2914 if (transaction)
2915 tid = transaction->t_tid;
2916 else
2917 tid = journal->j_commit_sequence;
2918 spin_unlock(&journal->j_state_lock);
2919 atomic_set(&ei->i_sync_tid, tid);
2920 atomic_set(&ei->i_datasync_tid, tid);
2921 }
2922
Linus Torvalds1da177e2005-04-16 15:20:36 -07002923 if (inode->i_ino >= EXT3_FIRST_INO(inode->i_sb) + 1 &&
2924 EXT3_INODE_SIZE(inode->i_sb) > EXT3_GOOD_OLD_INODE_SIZE) {
2925 /*
2926 * When mke2fs creates big inodes it does not zero out
2927 * the unused bytes above EXT3_GOOD_OLD_INODE_SIZE,
2928 * so ignore those first few inodes.
2929 */
2930 ei->i_extra_isize = le16_to_cpu(raw_inode->i_extra_isize);
2931 if (EXT3_GOOD_OLD_INODE_SIZE + ei->i_extra_isize >
Kirill Korotaeve4a10a32007-06-23 17:16:48 -07002932 EXT3_INODE_SIZE(inode->i_sb)) {
2933 brelse (bh);
David Howells473043d2008-02-07 00:15:36 -08002934 ret = -EIO;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002935 goto bad_inode;
Kirill Korotaeve4a10a32007-06-23 17:16:48 -07002936 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07002937 if (ei->i_extra_isize == 0) {
2938 /* The extra space is currently unused. Use it. */
2939 ei->i_extra_isize = sizeof(struct ext3_inode) -
2940 EXT3_GOOD_OLD_INODE_SIZE;
2941 } else {
2942 __le32 *magic = (void *)raw_inode +
2943 EXT3_GOOD_OLD_INODE_SIZE +
2944 ei->i_extra_isize;
2945 if (*magic == cpu_to_le32(EXT3_XATTR_MAGIC))
Jan Kara9df93932010-01-06 21:58:48 +01002946 ext3_set_inode_state(inode, EXT3_STATE_XATTR);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002947 }
2948 } else
2949 ei->i_extra_isize = 0;
2950
2951 if (S_ISREG(inode->i_mode)) {
2952 inode->i_op = &ext3_file_inode_operations;
2953 inode->i_fop = &ext3_file_operations;
2954 ext3_set_aops(inode);
2955 } else if (S_ISDIR(inode->i_mode)) {
2956 inode->i_op = &ext3_dir_inode_operations;
2957 inode->i_fop = &ext3_dir_operations;
2958 } else if (S_ISLNK(inode->i_mode)) {
Duane Griffinb5ed3112008-12-19 20:47:14 +00002959 if (ext3_inode_is_fast_symlink(inode)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002960 inode->i_op = &ext3_fast_symlink_inode_operations;
Duane Griffinb5ed3112008-12-19 20:47:14 +00002961 nd_terminate_link(ei->i_data, inode->i_size,
2962 sizeof(ei->i_data) - 1);
2963 } else {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002964 inode->i_op = &ext3_symlink_inode_operations;
2965 ext3_set_aops(inode);
2966 }
2967 } else {
2968 inode->i_op = &ext3_special_inode_operations;
2969 if (raw_inode->i_block[0])
2970 init_special_inode(inode, inode->i_mode,
2971 old_decode_dev(le32_to_cpu(raw_inode->i_block[0])));
Mingming Caoae6ddcc2006-09-27 01:49:27 -07002972 else
Linus Torvalds1da177e2005-04-16 15:20:36 -07002973 init_special_inode(inode, inode->i_mode,
2974 new_decode_dev(le32_to_cpu(raw_inode->i_block[1])));
2975 }
2976 brelse (iloc.bh);
2977 ext3_set_inode_flags(inode);
David Howells473043d2008-02-07 00:15:36 -08002978 unlock_new_inode(inode);
2979 return inode;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002980
2981bad_inode:
David Howells473043d2008-02-07 00:15:36 -08002982 iget_failed(inode);
2983 return ERR_PTR(ret);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002984}
2985
2986/*
2987 * Post the struct inode info into an on-disk inode location in the
2988 * buffer-cache. This gobbles the caller's reference to the
2989 * buffer_head in the inode location struct.
2990 *
2991 * The caller must have write access to iloc->bh.
2992 */
Mingming Caoae6ddcc2006-09-27 01:49:27 -07002993static int ext3_do_update_inode(handle_t *handle,
2994 struct inode *inode,
Linus Torvalds1da177e2005-04-16 15:20:36 -07002995 struct ext3_iloc *iloc)
2996{
2997 struct ext3_inode *raw_inode = ext3_raw_inode(iloc);
2998 struct ext3_inode_info *ei = EXT3_I(inode);
2999 struct buffer_head *bh = iloc->bh;
3000 int err = 0, rc, block;
3001
Chris Mason4f003fd2009-09-08 00:22:14 +02003002again:
3003 /* we can't allow multiple procs in here at once, its a bit racey */
3004 lock_buffer(bh);
3005
Linus Torvalds1da177e2005-04-16 15:20:36 -07003006 /* For fields not not tracking in the in-memory inode,
3007 * initialise them to zero for new inodes. */
Jan Kara9df93932010-01-06 21:58:48 +01003008 if (ext3_test_inode_state(inode, EXT3_STATE_NEW))
Linus Torvalds1da177e2005-04-16 15:20:36 -07003009 memset(raw_inode, 0, EXT3_SB(inode->i_sb)->s_inode_size);
3010
Jan Kara28be5ab2007-05-08 00:30:33 -07003011 ext3_get_inode_flags(ei);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003012 raw_inode->i_mode = cpu_to_le16(inode->i_mode);
3013 if(!(test_opt(inode->i_sb, NO_UID32))) {
3014 raw_inode->i_uid_low = cpu_to_le16(low_16_bits(inode->i_uid));
3015 raw_inode->i_gid_low = cpu_to_le16(low_16_bits(inode->i_gid));
3016/*
3017 * Fix up interoperability with old kernels. Otherwise, old inodes get
3018 * re-used with the upper 16 bits of the uid/gid intact
3019 */
3020 if(!ei->i_dtime) {
3021 raw_inode->i_uid_high =
3022 cpu_to_le16(high_16_bits(inode->i_uid));
3023 raw_inode->i_gid_high =
3024 cpu_to_le16(high_16_bits(inode->i_gid));
3025 } else {
3026 raw_inode->i_uid_high = 0;
3027 raw_inode->i_gid_high = 0;
3028 }
3029 } else {
3030 raw_inode->i_uid_low =
3031 cpu_to_le16(fs_high2lowuid(inode->i_uid));
3032 raw_inode->i_gid_low =
3033 cpu_to_le16(fs_high2lowgid(inode->i_gid));
3034 raw_inode->i_uid_high = 0;
3035 raw_inode->i_gid_high = 0;
3036 }
3037 raw_inode->i_links_count = cpu_to_le16(inode->i_nlink);
3038 raw_inode->i_size = cpu_to_le32(ei->i_disksize);
3039 raw_inode->i_atime = cpu_to_le32(inode->i_atime.tv_sec);
3040 raw_inode->i_ctime = cpu_to_le32(inode->i_ctime.tv_sec);
3041 raw_inode->i_mtime = cpu_to_le32(inode->i_mtime.tv_sec);
3042 raw_inode->i_blocks = cpu_to_le32(inode->i_blocks);
3043 raw_inode->i_dtime = cpu_to_le32(ei->i_dtime);
3044 raw_inode->i_flags = cpu_to_le32(ei->i_flags);
3045#ifdef EXT3_FRAGMENTS
3046 raw_inode->i_faddr = cpu_to_le32(ei->i_faddr);
3047 raw_inode->i_frag = ei->i_frag_no;
3048 raw_inode->i_fsize = ei->i_frag_size;
3049#endif
3050 raw_inode->i_file_acl = cpu_to_le32(ei->i_file_acl);
3051 if (!S_ISREG(inode->i_mode)) {
3052 raw_inode->i_dir_acl = cpu_to_le32(ei->i_dir_acl);
3053 } else {
3054 raw_inode->i_size_high =
3055 cpu_to_le32(ei->i_disksize >> 32);
3056 if (ei->i_disksize > 0x7fffffffULL) {
3057 struct super_block *sb = inode->i_sb;
3058 if (!EXT3_HAS_RO_COMPAT_FEATURE(sb,
3059 EXT3_FEATURE_RO_COMPAT_LARGE_FILE) ||
3060 EXT3_SB(sb)->s_es->s_rev_level ==
3061 cpu_to_le32(EXT3_GOOD_OLD_REV)) {
3062 /* If this is the first large file
3063 * created, add a flag to the superblock.
3064 */
Chris Mason4f003fd2009-09-08 00:22:14 +02003065 unlock_buffer(bh);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003066 err = ext3_journal_get_write_access(handle,
3067 EXT3_SB(sb)->s_sbh);
3068 if (err)
3069 goto out_brelse;
Chris Mason4f003fd2009-09-08 00:22:14 +02003070
Linus Torvalds1da177e2005-04-16 15:20:36 -07003071 ext3_update_dynamic_rev(sb);
3072 EXT3_SET_RO_COMPAT_FEATURE(sb,
3073 EXT3_FEATURE_RO_COMPAT_LARGE_FILE);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003074 handle->h_sync = 1;
3075 err = ext3_journal_dirty_metadata(handle,
3076 EXT3_SB(sb)->s_sbh);
Chris Mason4f003fd2009-09-08 00:22:14 +02003077 /* get our lock and start over */
3078 goto again;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003079 }
3080 }
3081 }
3082 raw_inode->i_generation = cpu_to_le32(inode->i_generation);
3083 if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) {
3084 if (old_valid_dev(inode->i_rdev)) {
3085 raw_inode->i_block[0] =
3086 cpu_to_le32(old_encode_dev(inode->i_rdev));
3087 raw_inode->i_block[1] = 0;
3088 } else {
3089 raw_inode->i_block[0] = 0;
3090 raw_inode->i_block[1] =
3091 cpu_to_le32(new_encode_dev(inode->i_rdev));
3092 raw_inode->i_block[2] = 0;
3093 }
3094 } else for (block = 0; block < EXT3_N_BLOCKS; block++)
3095 raw_inode->i_block[block] = ei->i_data[block];
3096
Andreas Gruenbacherff87b372005-07-07 17:57:00 -07003097 if (ei->i_extra_isize)
Linus Torvalds1da177e2005-04-16 15:20:36 -07003098 raw_inode->i_extra_isize = cpu_to_le16(ei->i_extra_isize);
3099
3100 BUFFER_TRACE(bh, "call ext3_journal_dirty_metadata");
Chris Mason4f003fd2009-09-08 00:22:14 +02003101 unlock_buffer(bh);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003102 rc = ext3_journal_dirty_metadata(handle, bh);
3103 if (!err)
3104 err = rc;
Jan Kara9df93932010-01-06 21:58:48 +01003105 ext3_clear_inode_state(inode, EXT3_STATE_NEW);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003106
Jan Karafe8bc912009-10-16 19:26:15 +02003107 atomic_set(&ei->i_sync_tid, handle->h_transaction->t_tid);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003108out_brelse:
3109 brelse (bh);
3110 ext3_std_error(inode->i_sb, err);
3111 return err;
3112}
3113
3114/*
3115 * ext3_write_inode()
3116 *
3117 * We are called from a few places:
3118 *
3119 * - Within generic_file_write() for O_SYNC files.
3120 * Here, there will be no transaction running. We wait for any running
3121 * trasnaction to commit.
3122 *
3123 * - Within sys_sync(), kupdate and such.
3124 * We wait on commit, if tol to.
3125 *
3126 * - Within prune_icache() (PF_MEMALLOC == true)
3127 * Here we simply return. We can't afford to block kswapd on the
3128 * journal commit.
3129 *
3130 * In all cases it is actually safe for us to return without doing anything,
3131 * because the inode has been copied into a raw inode buffer in
3132 * ext3_mark_inode_dirty(). This is a correctness thing for O_SYNC and for
3133 * knfsd.
3134 *
3135 * Note that we are absolutely dependent upon all inode dirtiers doing the
3136 * right thing: they *must* call mark_inode_dirty() after dirtying info in
3137 * which we are interested.
3138 *
3139 * It would be a bug for them to not do this. The code:
3140 *
3141 * mark_inode_dirty(inode)
3142 * stuff();
3143 * inode->i_size = expr;
3144 *
3145 * is in error because a kswapd-driven write_inode() could occur while
3146 * `stuff()' is running, and the new i_size will be lost. Plus the inode
3147 * will no longer be on the superblock's dirty inode list.
3148 */
Christoph Hellwiga9185b42010-03-05 09:21:37 +01003149int ext3_write_inode(struct inode *inode, struct writeback_control *wbc)
Linus Torvalds1da177e2005-04-16 15:20:36 -07003150{
3151 if (current->flags & PF_MEMALLOC)
3152 return 0;
3153
3154 if (ext3_journal_current_handle()) {
Jose R. Santos9ad163a2007-10-18 23:39:23 -07003155 jbd_debug(1, "called recursively, non-PF_MEMALLOC!\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -07003156 dump_stack();
3157 return -EIO;
3158 }
3159
Christoph Hellwiga9185b42010-03-05 09:21:37 +01003160 if (wbc->sync_mode != WB_SYNC_ALL)
Linus Torvalds1da177e2005-04-16 15:20:36 -07003161 return 0;
3162
3163 return ext3_force_commit(inode->i_sb);
3164}
3165
3166/*
3167 * ext3_setattr()
3168 *
3169 * Called from notify_change.
3170 *
3171 * We want to trap VFS attempts to truncate the file as soon as
3172 * possible. In particular, we want to make sure that when the VFS
3173 * shrinks i_size, we put the inode on the orphan list and modify
3174 * i_disksize immediately, so that during the subsequent flushing of
3175 * dirty pages and freeing of disk blocks, we can guarantee that any
3176 * commit will leave the blocks being flushed in an unused state on
3177 * disk. (On recovery, the inode will get truncated and the blocks will
3178 * be freed, so we have a strong guarantee that no future commit will
Mingming Caoae6ddcc2006-09-27 01:49:27 -07003179 * leave these blocks visible to the user.)
Linus Torvalds1da177e2005-04-16 15:20:36 -07003180 *
3181 * Called with inode->sem down.
3182 */
3183int ext3_setattr(struct dentry *dentry, struct iattr *attr)
3184{
3185 struct inode *inode = dentry->d_inode;
3186 int error, rc = 0;
3187 const unsigned int ia_valid = attr->ia_valid;
3188
3189 error = inode_change_ok(inode, attr);
3190 if (error)
3191 return error;
3192
Dmitry Monakhov12755622010-04-08 22:04:20 +04003193 if (is_quota_modification(inode, attr))
Christoph Hellwig871a2932010-03-03 09:05:07 -05003194 dquot_initialize(inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003195 if ((ia_valid & ATTR_UID && attr->ia_uid != inode->i_uid) ||
3196 (ia_valid & ATTR_GID && attr->ia_gid != inode->i_gid)) {
3197 handle_t *handle;
3198
3199 /* (user+group)*(old+new) structure, inode write (sb,
3200 * inode block, ? - but truncate inode update has it) */
Dmitry Monakhovc4590012009-12-09 03:05:30 +03003201 handle = ext3_journal_start(inode, EXT3_MAXQUOTAS_INIT_BLOCKS(inode->i_sb)+
3202 EXT3_MAXQUOTAS_DEL_BLOCKS(inode->i_sb)+3);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003203 if (IS_ERR(handle)) {
3204 error = PTR_ERR(handle);
3205 goto err_out;
3206 }
Christoph Hellwigb43fa822010-03-03 09:05:03 -05003207 error = dquot_transfer(inode, attr);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003208 if (error) {
3209 ext3_journal_stop(handle);
3210 return error;
3211 }
3212 /* Update corresponding info in inode so that everything is in
3213 * one transaction */
3214 if (attr->ia_valid & ATTR_UID)
3215 inode->i_uid = attr->ia_uid;
3216 if (attr->ia_valid & ATTR_GID)
3217 inode->i_gid = attr->ia_gid;
3218 error = ext3_mark_inode_dirty(handle, inode);
3219 ext3_journal_stop(handle);
3220 }
3221
3222 if (S_ISREG(inode->i_mode) &&
3223 attr->ia_valid & ATTR_SIZE && attr->ia_size < inode->i_size) {
3224 handle_t *handle;
3225
3226 handle = ext3_journal_start(inode, 3);
3227 if (IS_ERR(handle)) {
3228 error = PTR_ERR(handle);
3229 goto err_out;
3230 }
3231
3232 error = ext3_orphan_add(handle, inode);
3233 EXT3_I(inode)->i_disksize = attr->ia_size;
3234 rc = ext3_mark_inode_dirty(handle, inode);
3235 if (!error)
3236 error = rc;
3237 ext3_journal_stop(handle);
3238 }
3239
Christoph Hellwig10257742010-06-04 11:30:02 +02003240 if ((attr->ia_valid & ATTR_SIZE) &&
3241 attr->ia_size != i_size_read(inode)) {
3242 rc = vmtruncate(inode, attr->ia_size);
3243 if (rc)
3244 goto err_out;
3245 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07003246
Christoph Hellwig10257742010-06-04 11:30:02 +02003247 setattr_copy(inode, attr);
3248 mark_inode_dirty(inode);
3249
3250 if (ia_valid & ATTR_MODE)
Linus Torvalds1da177e2005-04-16 15:20:36 -07003251 rc = ext3_acl_chmod(inode);
3252
3253err_out:
3254 ext3_std_error(inode->i_sb, error);
3255 if (!error)
3256 error = rc;
3257 return error;
3258}
3259
3260
3261/*
Andrew Mortond6859bf2006-03-26 01:38:03 -08003262 * How many blocks doth make a writepage()?
Linus Torvalds1da177e2005-04-16 15:20:36 -07003263 *
3264 * With N blocks per page, it may be:
3265 * N data blocks
3266 * 2 indirect block
3267 * 2 dindirect
3268 * 1 tindirect
3269 * N+5 bitmap blocks (from the above)
3270 * N+5 group descriptor summary blocks
3271 * 1 inode block
3272 * 1 superblock.
3273 * 2 * EXT3_SINGLEDATA_TRANS_BLOCKS for the quote files
3274 *
3275 * 3 * (N + 5) + 2 + 2 * EXT3_SINGLEDATA_TRANS_BLOCKS
3276 *
3277 * With ordered or writeback data it's the same, less the N data blocks.
3278 *
3279 * If the inode's direct blocks can hold an integral number of pages then a
3280 * page cannot straddle two indirect blocks, and we can only touch one indirect
3281 * and dindirect block, and the "5" above becomes "3".
3282 *
3283 * This still overestimates under most circumstances. If we were to pass the
3284 * start and end offsets in here as well we could do block_to_path() on each
3285 * block and work out the exact number of indirects which are touched. Pah.
3286 */
3287
3288static int ext3_writepage_trans_blocks(struct inode *inode)
3289{
3290 int bpp = ext3_journal_blocks_per_page(inode);
3291 int indirects = (EXT3_NDIR_BLOCKS % bpp) ? 5 : 3;
3292 int ret;
3293
3294 if (ext3_should_journal_data(inode))
3295 ret = 3 * (bpp + indirects) + 2;
3296 else
3297 ret = 2 * (bpp + indirects) + 2;
3298
3299#ifdef CONFIG_QUOTA
Christoph Hellwig871a2932010-03-03 09:05:07 -05003300 /* We know that structure was already allocated during dquot_initialize so
Linus Torvalds1da177e2005-04-16 15:20:36 -07003301 * we will be updating only the data blocks + inodes */
Dmitry Monakhovc4590012009-12-09 03:05:30 +03003302 ret += EXT3_MAXQUOTAS_TRANS_BLOCKS(inode->i_sb);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003303#endif
3304
3305 return ret;
3306}
3307
3308/*
3309 * The caller must have previously called ext3_reserve_inode_write().
3310 * Give this, we know that the caller already has write access to iloc->bh.
3311 */
3312int ext3_mark_iloc_dirty(handle_t *handle,
3313 struct inode *inode, struct ext3_iloc *iloc)
3314{
3315 int err = 0;
3316
3317 /* the do_update_inode consumes one bh->b_count */
3318 get_bh(iloc->bh);
3319
3320 /* ext3_do_update_inode() does journal_dirty_metadata */
3321 err = ext3_do_update_inode(handle, inode, iloc);
3322 put_bh(iloc->bh);
3323 return err;
3324}
3325
Mingming Caoae6ddcc2006-09-27 01:49:27 -07003326/*
Linus Torvalds1da177e2005-04-16 15:20:36 -07003327 * On success, We end up with an outstanding reference count against
Mingming Caoae6ddcc2006-09-27 01:49:27 -07003328 * iloc->bh. This _must_ be cleaned up later.
Linus Torvalds1da177e2005-04-16 15:20:36 -07003329 */
3330
3331int
Mingming Caoae6ddcc2006-09-27 01:49:27 -07003332ext3_reserve_inode_write(handle_t *handle, struct inode *inode,
Linus Torvalds1da177e2005-04-16 15:20:36 -07003333 struct ext3_iloc *iloc)
3334{
3335 int err = 0;
3336 if (handle) {
3337 err = ext3_get_inode_loc(inode, iloc);
3338 if (!err) {
3339 BUFFER_TRACE(iloc->bh, "get_write_access");
3340 err = ext3_journal_get_write_access(handle, iloc->bh);
3341 if (err) {
3342 brelse(iloc->bh);
3343 iloc->bh = NULL;
3344 }
3345 }
3346 }
3347 ext3_std_error(inode->i_sb, err);
3348 return err;
3349}
3350
3351/*
Andrew Mortond6859bf2006-03-26 01:38:03 -08003352 * What we do here is to mark the in-core inode as clean with respect to inode
3353 * dirtiness (it may still be data-dirty).
Linus Torvalds1da177e2005-04-16 15:20:36 -07003354 * This means that the in-core inode may be reaped by prune_icache
3355 * without having to perform any I/O. This is a very good thing,
3356 * because *any* task may call prune_icache - even ones which
3357 * have a transaction open against a different journal.
3358 *
3359 * Is this cheating? Not really. Sure, we haven't written the
3360 * inode out, but prune_icache isn't a user-visible syncing function.
3361 * Whenever the user wants stuff synced (sys_sync, sys_msync, sys_fsync)
3362 * we start and wait on commits.
3363 *
3364 * Is this efficient/effective? Well, we're being nice to the system
3365 * by cleaning up our inodes proactively so they can be reaped
3366 * without I/O. But we are potentially leaving up to five seconds'
3367 * worth of inodes floating about which prune_icache wants us to
3368 * write out. One way to fix that would be to get prune_icache()
3369 * to do a write_super() to free up some memory. It has the desired
3370 * effect.
3371 */
3372int ext3_mark_inode_dirty(handle_t *handle, struct inode *inode)
3373{
3374 struct ext3_iloc iloc;
3375 int err;
3376
3377 might_sleep();
3378 err = ext3_reserve_inode_write(handle, inode, &iloc);
3379 if (!err)
3380 err = ext3_mark_iloc_dirty(handle, inode, &iloc);
3381 return err;
3382}
3383
3384/*
Andrew Mortond6859bf2006-03-26 01:38:03 -08003385 * ext3_dirty_inode() is called from __mark_inode_dirty()
Linus Torvalds1da177e2005-04-16 15:20:36 -07003386 *
3387 * We're really interested in the case where a file is being extended.
3388 * i_size has been changed by generic_commit_write() and we thus need
3389 * to include the updated inode in the current transaction.
3390 *
Christoph Hellwig5dd40562010-03-03 09:05:00 -05003391 * Also, dquot_alloc_space() will always dirty the inode when blocks
Linus Torvalds1da177e2005-04-16 15:20:36 -07003392 * are allocated to the file.
3393 *
3394 * If the inode is marked synchronous, we don't honour that here - doing
3395 * so would cause a commit on atime updates, which we don't bother doing.
3396 * We handle synchronous inodes at the highest possible level.
3397 */
3398void ext3_dirty_inode(struct inode *inode)
3399{
3400 handle_t *current_handle = ext3_journal_current_handle();
3401 handle_t *handle;
3402
3403 handle = ext3_journal_start(inode, 2);
3404 if (IS_ERR(handle))
3405 goto out;
3406 if (current_handle &&
3407 current_handle->h_transaction != handle->h_transaction) {
3408 /* This task has a transaction open against a different fs */
3409 printk(KERN_EMERG "%s: transactions do not match!\n",
Harvey Harrisone05b6b52008-04-28 02:16:15 -07003410 __func__);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003411 } else {
3412 jbd_debug(5, "marking dirty. outer handle=%p\n",
3413 current_handle);
3414 ext3_mark_inode_dirty(handle, inode);
3415 }
3416 ext3_journal_stop(handle);
3417out:
3418 return;
3419}
3420
Andrew Mortond6859bf2006-03-26 01:38:03 -08003421#if 0
Mingming Caoae6ddcc2006-09-27 01:49:27 -07003422/*
Linus Torvalds1da177e2005-04-16 15:20:36 -07003423 * Bind an inode's backing buffer_head into this transaction, to prevent
3424 * it from being flushed to disk early. Unlike
3425 * ext3_reserve_inode_write, this leaves behind no bh reference and
3426 * returns no iloc structure, so the caller needs to repeat the iloc
3427 * lookup to mark the inode dirty later.
3428 */
Andrew Mortond6859bf2006-03-26 01:38:03 -08003429static int ext3_pin_inode(handle_t *handle, struct inode *inode)
Linus Torvalds1da177e2005-04-16 15:20:36 -07003430{
3431 struct ext3_iloc iloc;
3432
3433 int err = 0;
3434 if (handle) {
3435 err = ext3_get_inode_loc(inode, &iloc);
3436 if (!err) {
3437 BUFFER_TRACE(iloc.bh, "get_write_access");
3438 err = journal_get_write_access(handle, iloc.bh);
3439 if (!err)
Mingming Caoae6ddcc2006-09-27 01:49:27 -07003440 err = ext3_journal_dirty_metadata(handle,
Linus Torvalds1da177e2005-04-16 15:20:36 -07003441 iloc.bh);
3442 brelse(iloc.bh);
3443 }
3444 }
3445 ext3_std_error(inode->i_sb, err);
3446 return err;
3447}
3448#endif
3449
3450int ext3_change_inode_journal_flag(struct inode *inode, int val)
3451{
3452 journal_t *journal;
3453 handle_t *handle;
3454 int err;
3455
3456 /*
3457 * We have to be very careful here: changing a data block's
3458 * journaling status dynamically is dangerous. If we write a
3459 * data block to the journal, change the status and then delete
3460 * that block, we risk forgetting to revoke the old log record
3461 * from the journal and so a subsequent replay can corrupt data.
3462 * So, first we make sure that the journal is empty and that
3463 * nobody is changing anything.
3464 */
3465
3466 journal = EXT3_JOURNAL(inode);
Dave Hansene3a68e32007-07-15 23:41:14 -07003467 if (is_journal_aborted(journal))
Linus Torvalds1da177e2005-04-16 15:20:36 -07003468 return -EROFS;
3469
3470 journal_lock_updates(journal);
3471 journal_flush(journal);
3472
3473 /*
3474 * OK, there are no updates running now, and all cached data is
3475 * synced to disk. We are now in a completely consistent state
3476 * which doesn't have anything in the journal, and we know that
3477 * no filesystem updates are running, so it is safe to modify
3478 * the inode's in-core data-journaling state flag now.
3479 */
3480
3481 if (val)
3482 EXT3_I(inode)->i_flags |= EXT3_JOURNAL_DATA_FL;
3483 else
3484 EXT3_I(inode)->i_flags &= ~EXT3_JOURNAL_DATA_FL;
3485 ext3_set_aops(inode);
3486
3487 journal_unlock_updates(journal);
3488
3489 /* Finally we can mark the inode as dirty. */
3490
3491 handle = ext3_journal_start(inode, 1);
3492 if (IS_ERR(handle))
3493 return PTR_ERR(handle);
3494
3495 err = ext3_mark_inode_dirty(handle, inode);
3496 handle->h_sync = 1;
3497 ext3_journal_stop(handle);
3498 ext3_std_error(inode->i_sb, err);
3499
3500 return err;
3501}