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Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * linux/fs/ext3/inode.c
3 *
4 * Copyright (C) 1992, 1993, 1994, 1995
5 * Remy Card (card@masi.ibp.fr)
6 * Laboratoire MASI - Institut Blaise Pascal
7 * Universite Pierre et Marie Curie (Paris VI)
8 *
9 * from
10 *
11 * linux/fs/minix/inode.c
12 *
13 * Copyright (C) 1991, 1992 Linus Torvalds
14 *
15 * Goal-directed block allocation by Stephen Tweedie
Dave Kleikampe9ad5622006-09-27 01:49:35 -070016 * (sct@redhat.com), 1993, 1998
Linus Torvalds1da177e2005-04-16 15:20:36 -070017 * Big-endian to little-endian byte-swapping/bitmaps by
18 * David S. Miller (davem@caip.rutgers.edu), 1995
19 * 64-bit file support on 64-bit platforms by Jakub Jelinek
Dave Kleikampe9ad5622006-09-27 01:49:35 -070020 * (jj@sunsite.ms.mff.cuni.cz)
Linus Torvalds1da177e2005-04-16 15:20:36 -070021 *
22 * Assorted race fixes, rewrite of ext3_get_block() by Al Viro, 2000
23 */
24
25#include <linux/module.h>
26#include <linux/fs.h>
27#include <linux/time.h>
28#include <linux/ext3_jbd.h>
29#include <linux/jbd.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070030#include <linux/highuid.h>
31#include <linux/pagemap.h>
32#include <linux/quotaops.h>
33#include <linux/string.h>
34#include <linux/buffer_head.h>
35#include <linux/writeback.h>
36#include <linux/mpage.h>
37#include <linux/uio.h>
Jens Axboecaa38fb2006-07-23 01:41:26 +020038#include <linux/bio.h>
Josef Bacik68c9d702008-10-03 17:32:43 -040039#include <linux/fiemap.h>
Duane Griffinb5ed3112008-12-19 20:47:14 +000040#include <linux/namei.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070041#include "xattr.h"
42#include "acl.h"
43
44static int ext3_writepage_trans_blocks(struct inode *inode);
45
46/*
47 * Test whether an inode is a fast symlink.
48 */
Andrew Mortond6859bf2006-03-26 01:38:03 -080049static int ext3_inode_is_fast_symlink(struct inode *inode)
Linus Torvalds1da177e2005-04-16 15:20:36 -070050{
51 int ea_blocks = EXT3_I(inode)->i_file_acl ?
52 (inode->i_sb->s_blocksize >> 9) : 0;
53
Andrew Mortond6859bf2006-03-26 01:38:03 -080054 return (S_ISLNK(inode->i_mode) && inode->i_blocks - ea_blocks == 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -070055}
56
Andrew Mortond6859bf2006-03-26 01:38:03 -080057/*
58 * The ext3 forget function must perform a revoke if we are freeing data
Linus Torvalds1da177e2005-04-16 15:20:36 -070059 * which has been journaled. Metadata (eg. indirect blocks) must be
Mingming Caoae6ddcc2006-09-27 01:49:27 -070060 * revoked in all cases.
Linus Torvalds1da177e2005-04-16 15:20:36 -070061 *
62 * "bh" may be NULL: a metadata block may have been freed from memory
63 * but there may still be a record of it in the journal, and that record
64 * still needs to be revoked.
65 */
Andrew Mortond6859bf2006-03-26 01:38:03 -080066int ext3_forget(handle_t *handle, int is_metadata, struct inode *inode,
Mingming Cao1c2bf372006-06-25 05:48:06 -070067 struct buffer_head *bh, ext3_fsblk_t blocknr)
Linus Torvalds1da177e2005-04-16 15:20:36 -070068{
69 int err;
70
71 might_sleep();
72
73 BUFFER_TRACE(bh, "enter");
74
75 jbd_debug(4, "forgetting bh %p: is_metadata = %d, mode %o, "
76 "data mode %lx\n",
77 bh, is_metadata, inode->i_mode,
78 test_opt(inode->i_sb, DATA_FLAGS));
79
80 /* Never use the revoke function if we are doing full data
81 * journaling: there is no need to, and a V1 superblock won't
82 * support it. Otherwise, only skip the revoke on un-journaled
83 * data blocks. */
84
85 if (test_opt(inode->i_sb, DATA_FLAGS) == EXT3_MOUNT_JOURNAL_DATA ||
86 (!is_metadata && !ext3_should_journal_data(inode))) {
87 if (bh) {
88 BUFFER_TRACE(bh, "call journal_forget");
89 return ext3_journal_forget(handle, bh);
90 }
91 return 0;
92 }
93
94 /*
95 * data!=journal && (is_metadata || should_journal_data(inode))
96 */
97 BUFFER_TRACE(bh, "call ext3_journal_revoke");
98 err = ext3_journal_revoke(handle, blocknr, bh);
99 if (err)
Harvey Harrisone05b6b52008-04-28 02:16:15 -0700100 ext3_abort(inode->i_sb, __func__,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700101 "error %d when attempting revoke", err);
102 BUFFER_TRACE(bh, "exit");
103 return err;
104}
105
106/*
Andrew Mortond6859bf2006-03-26 01:38:03 -0800107 * Work out how many blocks we need to proceed with the next chunk of a
Linus Torvalds1da177e2005-04-16 15:20:36 -0700108 * truncate transaction.
109 */
Mingming Caoae6ddcc2006-09-27 01:49:27 -0700110static unsigned long blocks_for_truncate(struct inode *inode)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700111{
112 unsigned long needed;
113
114 needed = inode->i_blocks >> (inode->i_sb->s_blocksize_bits - 9);
115
116 /* Give ourselves just enough room to cope with inodes in which
117 * i_blocks is corrupt: we've seen disk corruptions in the past
118 * which resulted in random data in an inode which looked enough
119 * like a regular file for ext3 to try to delete it. Things
120 * will go a bit crazy if that happens, but at least we should
121 * try not to panic the whole kernel. */
122 if (needed < 2)
123 needed = 2;
124
125 /* But we need to bound the transaction so we don't overflow the
126 * journal. */
Mingming Caoae6ddcc2006-09-27 01:49:27 -0700127 if (needed > EXT3_MAX_TRANS_DATA)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700128 needed = EXT3_MAX_TRANS_DATA;
129
Jan Kara1f545872005-06-23 22:01:04 -0700130 return EXT3_DATA_TRANS_BLOCKS(inode->i_sb) + needed;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700131}
132
Mingming Caoae6ddcc2006-09-27 01:49:27 -0700133/*
Linus Torvalds1da177e2005-04-16 15:20:36 -0700134 * Truncate transactions can be complex and absolutely huge. So we need to
135 * be able to restart the transaction at a conventient checkpoint to make
136 * sure we don't overflow the journal.
137 *
138 * start_transaction gets us a new handle for a truncate transaction,
139 * and extend_transaction tries to extend the existing one a bit. If
140 * extend fails, we need to propagate the failure up and restart the
Mingming Caoae6ddcc2006-09-27 01:49:27 -0700141 * transaction in the top-level truncate loop. --sct
Linus Torvalds1da177e2005-04-16 15:20:36 -0700142 */
Mingming Caoae6ddcc2006-09-27 01:49:27 -0700143static handle_t *start_transaction(struct inode *inode)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700144{
145 handle_t *result;
146
147 result = ext3_journal_start(inode, blocks_for_truncate(inode));
148 if (!IS_ERR(result))
149 return result;
150
151 ext3_std_error(inode->i_sb, PTR_ERR(result));
152 return result;
153}
154
155/*
156 * Try to extend this transaction for the purposes of truncation.
157 *
158 * Returns 0 if we managed to create more room. If we can't create more
159 * room, and the transaction must be restarted we return 1.
160 */
161static int try_to_extend_transaction(handle_t *handle, struct inode *inode)
162{
163 if (handle->h_buffer_credits > EXT3_RESERVE_TRANS_BLOCKS)
164 return 0;
165 if (!ext3_journal_extend(handle, blocks_for_truncate(inode)))
166 return 0;
167 return 1;
168}
169
170/*
171 * Restart the transaction associated with *handle. This does a commit,
172 * so before we call here everything must be consistently dirtied against
173 * this transaction.
174 */
Jan Kara00171d32009-08-11 19:06:10 +0200175static int truncate_restart_transaction(handle_t *handle, struct inode *inode)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700176{
Jan Kara00171d32009-08-11 19:06:10 +0200177 int ret;
178
Linus Torvalds1da177e2005-04-16 15:20:36 -0700179 jbd_debug(2, "restarting handle %p\n", handle);
Jan Kara00171d32009-08-11 19:06:10 +0200180 /*
181 * Drop truncate_mutex to avoid deadlock with ext3_get_blocks_handle
182 * At this moment, get_block can be called only for blocks inside
183 * i_size since page cache has been already dropped and writes are
184 * blocked by i_mutex. So we can safely drop the truncate_mutex.
185 */
186 mutex_unlock(&EXT3_I(inode)->truncate_mutex);
187 ret = ext3_journal_restart(handle, blocks_for_truncate(inode));
188 mutex_lock(&EXT3_I(inode)->truncate_mutex);
189 return ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700190}
191
192/*
Al Viroac14a952010-06-06 07:08:19 -0400193 * Called at inode eviction from icache
Linus Torvalds1da177e2005-04-16 15:20:36 -0700194 */
Al Viroac14a952010-06-06 07:08:19 -0400195void ext3_evict_inode (struct inode *inode)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700196{
Al Viroac14a952010-06-06 07:08:19 -0400197 struct ext3_block_alloc_info *rsv;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700198 handle_t *handle;
Al Viroac14a952010-06-06 07:08:19 -0400199 int want_delete = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700200
Al Viroac14a952010-06-06 07:08:19 -0400201 if (!inode->i_nlink && !is_bad_inode(inode)) {
Christoph Hellwig871a2932010-03-03 09:05:07 -0500202 dquot_initialize(inode);
Al Viroac14a952010-06-06 07:08:19 -0400203 want_delete = 1;
204 }
Christoph Hellwig907f4552010-03-03 09:05:06 -0500205
Mark Fashehfef26652005-09-09 13:01:31 -0700206 truncate_inode_pages(&inode->i_data, 0);
207
Al Viroac14a952010-06-06 07:08:19 -0400208 ext3_discard_reservation(inode);
209 rsv = EXT3_I(inode)->i_block_alloc_info;
210 EXT3_I(inode)->i_block_alloc_info = NULL;
211 if (unlikely(rsv))
212 kfree(rsv);
213
214 if (!want_delete)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700215 goto no_delete;
216
217 handle = start_transaction(inode);
218 if (IS_ERR(handle)) {
Andrew Mortond6859bf2006-03-26 01:38:03 -0800219 /*
220 * If we're going to skip the normal cleanup, we still need to
221 * make sure that the in-core orphan linked list is properly
222 * cleaned up.
223 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700224 ext3_orphan_del(NULL, inode);
225 goto no_delete;
226 }
227
228 if (IS_SYNC(inode))
229 handle->h_sync = 1;
230 inode->i_size = 0;
231 if (inode->i_blocks)
232 ext3_truncate(inode);
233 /*
234 * Kill off the orphan record which ext3_truncate created.
235 * AKPM: I think this can be inside the above `if'.
236 * Note that ext3_orphan_del() has to be able to cope with the
237 * deletion of a non-existent orphan - this is because we don't
238 * know if ext3_truncate() actually created an orphan record.
239 * (Well, we could do this if we need to, but heck - it works)
240 */
241 ext3_orphan_del(handle, inode);
242 EXT3_I(inode)->i_dtime = get_seconds();
243
Mingming Caoae6ddcc2006-09-27 01:49:27 -0700244 /*
Linus Torvalds1da177e2005-04-16 15:20:36 -0700245 * One subtle ordering requirement: if anything has gone wrong
246 * (transaction abort, IO errors, whatever), then we can still
247 * do these next steps (the fs will already have been marked as
248 * having errors), but we can't free the inode if the mark_dirty
Mingming Caoae6ddcc2006-09-27 01:49:27 -0700249 * fails.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700250 */
Al Viroac14a952010-06-06 07:08:19 -0400251 if (ext3_mark_inode_dirty(handle, inode)) {
252 /* If that failed, just dquot_drop() and be done with that */
253 dquot_drop(inode);
254 end_writeback(inode);
255 } else {
256 ext3_xattr_delete_inode(handle, inode);
257 dquot_free_inode(inode);
258 dquot_drop(inode);
259 end_writeback(inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700260 ext3_free_inode(handle, inode);
Al Viroac14a952010-06-06 07:08:19 -0400261 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700262 ext3_journal_stop(handle);
263 return;
264no_delete:
Al Viroac14a952010-06-06 07:08:19 -0400265 end_writeback(inode);
266 dquot_drop(inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700267}
268
Linus Torvalds1da177e2005-04-16 15:20:36 -0700269typedef struct {
270 __le32 *p;
271 __le32 key;
272 struct buffer_head *bh;
273} Indirect;
274
275static inline void add_chain(Indirect *p, struct buffer_head *bh, __le32 *v)
276{
277 p->key = *(p->p = v);
278 p->bh = bh;
279}
280
Andrew Mortond6859bf2006-03-26 01:38:03 -0800281static int verify_chain(Indirect *from, Indirect *to)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700282{
283 while (from <= to && from->key == *from->p)
284 from++;
285 return (from > to);
286}
287
288/**
289 * ext3_block_to_path - parse the block number into array of offsets
290 * @inode: inode in question (we are only interested in its superblock)
291 * @i_block: block number to be parsed
292 * @offsets: array to store the offsets in
293 * @boundary: set this non-zero if the referred-to block is likely to be
294 * followed (on disk) by an indirect block.
295 *
296 * To store the locations of file's data ext3 uses a data structure common
297 * for UNIX filesystems - tree of pointers anchored in the inode, with
298 * data blocks at leaves and indirect blocks in intermediate nodes.
299 * This function translates the block number into path in that tree -
300 * return value is the path length and @offsets[n] is the offset of
301 * pointer to (n+1)th node in the nth one. If @block is out of range
302 * (negative or too large) warning is printed and zero returned.
303 *
304 * Note: function doesn't find node addresses, so no IO is needed. All
305 * we need to know is the capacity of indirect blocks (taken from the
306 * inode->i_sb).
307 */
308
309/*
310 * Portability note: the last comparison (check that we fit into triple
311 * indirect block) is spelled differently, because otherwise on an
312 * architecture with 32-bit longs and 8Kb pages we might get into trouble
313 * if our filesystem had 8Kb blocks. We might use long long, but that would
314 * kill us on x86. Oh, well, at least the sign propagation does not matter -
315 * i_block would have to be negative in the very beginning, so we would not
316 * get there at all.
317 */
318
319static int ext3_block_to_path(struct inode *inode,
320 long i_block, int offsets[4], int *boundary)
321{
322 int ptrs = EXT3_ADDR_PER_BLOCK(inode->i_sb);
323 int ptrs_bits = EXT3_ADDR_PER_BLOCK_BITS(inode->i_sb);
324 const long direct_blocks = EXT3_NDIR_BLOCKS,
325 indirect_blocks = ptrs,
326 double_blocks = (1 << (ptrs_bits * 2));
327 int n = 0;
328 int final = 0;
329
330 if (i_block < 0) {
331 ext3_warning (inode->i_sb, "ext3_block_to_path", "block < 0");
332 } else if (i_block < direct_blocks) {
333 offsets[n++] = i_block;
334 final = direct_blocks;
335 } else if ( (i_block -= direct_blocks) < indirect_blocks) {
336 offsets[n++] = EXT3_IND_BLOCK;
337 offsets[n++] = i_block;
338 final = ptrs;
339 } else if ((i_block -= indirect_blocks) < double_blocks) {
340 offsets[n++] = EXT3_DIND_BLOCK;
341 offsets[n++] = i_block >> ptrs_bits;
342 offsets[n++] = i_block & (ptrs - 1);
343 final = ptrs;
344 } else if (((i_block -= double_blocks) >> (ptrs_bits * 2)) < ptrs) {
345 offsets[n++] = EXT3_TIND_BLOCK;
346 offsets[n++] = i_block >> (ptrs_bits * 2);
347 offsets[n++] = (i_block >> ptrs_bits) & (ptrs - 1);
348 offsets[n++] = i_block & (ptrs - 1);
349 final = ptrs;
350 } else {
Andrew Mortond6859bf2006-03-26 01:38:03 -0800351 ext3_warning(inode->i_sb, "ext3_block_to_path", "block > big");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700352 }
353 if (boundary)
Mingming Cao89747d32006-03-26 01:37:55 -0800354 *boundary = final - 1 - (i_block & (ptrs - 1));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700355 return n;
356}
357
358/**
359 * ext3_get_branch - read the chain of indirect blocks leading to data
360 * @inode: inode in question
361 * @depth: depth of the chain (1 - direct pointer, etc.)
362 * @offsets: offsets of pointers in inode/indirect blocks
363 * @chain: place to store the result
364 * @err: here we store the error value
365 *
366 * Function fills the array of triples <key, p, bh> and returns %NULL
367 * if everything went OK or the pointer to the last filled triple
368 * (incomplete one) otherwise. Upon the return chain[i].key contains
369 * the number of (i+1)-th block in the chain (as it is stored in memory,
370 * i.e. little-endian 32-bit), chain[i].p contains the address of that
371 * number (it points into struct inode for i==0 and into the bh->b_data
372 * for i>0) and chain[i].bh points to the buffer_head of i-th indirect
373 * block for i>0 and NULL for i==0. In other words, it holds the block
374 * numbers of the chain, addresses they were taken from (and where we can
375 * verify that chain did not change) and buffer_heads hosting these
376 * numbers.
377 *
378 * Function stops when it stumbles upon zero pointer (absent block)
379 * (pointer to last triple returned, *@err == 0)
380 * or when it gets an IO error reading an indirect block
381 * (ditto, *@err == -EIO)
382 * or when it notices that chain had been changed while it was reading
383 * (ditto, *@err == -EAGAIN)
384 * or when it reads all @depth-1 indirect blocks successfully and finds
385 * the whole chain, all way to the data (returns %NULL, *err == 0).
386 */
387static Indirect *ext3_get_branch(struct inode *inode, int depth, int *offsets,
388 Indirect chain[4], int *err)
389{
390 struct super_block *sb = inode->i_sb;
391 Indirect *p = chain;
392 struct buffer_head *bh;
393
394 *err = 0;
395 /* i_data is not going away, no lock needed */
396 add_chain (chain, NULL, EXT3_I(inode)->i_data + *offsets);
397 if (!p->key)
398 goto no_block;
399 while (--depth) {
400 bh = sb_bread(sb, le32_to_cpu(p->key));
401 if (!bh)
402 goto failure;
403 /* Reader: pointers */
404 if (!verify_chain(chain, p))
405 goto changed;
406 add_chain(++p, bh, (__le32*)bh->b_data + *++offsets);
407 /* Reader: end */
408 if (!p->key)
409 goto no_block;
410 }
411 return NULL;
412
413changed:
414 brelse(bh);
415 *err = -EAGAIN;
416 goto no_block;
417failure:
418 *err = -EIO;
419no_block:
420 return p;
421}
422
423/**
424 * ext3_find_near - find a place for allocation with sufficient locality
425 * @inode: owner
426 * @ind: descriptor of indirect block.
427 *
Benoit Boissinot1cc8dcf2008-04-21 22:45:55 +0000428 * This function returns the preferred place for block allocation.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700429 * It is used when heuristic for sequential allocation fails.
430 * Rules are:
431 * + if there is a block to the left of our position - allocate near it.
432 * + if pointer will live in indirect block - allocate near that block.
433 * + if pointer will live in inode - allocate in the same
Mingming Caoae6ddcc2006-09-27 01:49:27 -0700434 * cylinder group.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700435 *
436 * In the latter case we colour the starting block by the callers PID to
437 * prevent it from clashing with concurrent allocations for a different inode
438 * in the same block group. The PID is used here so that functionally related
439 * files will be close-by on-disk.
440 *
441 * Caller must make sure that @ind is valid and will stay that way.
442 */
Mingming Cao43d23f92006-06-25 05:48:07 -0700443static ext3_fsblk_t ext3_find_near(struct inode *inode, Indirect *ind)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700444{
445 struct ext3_inode_info *ei = EXT3_I(inode);
446 __le32 *start = ind->bh ? (__le32*) ind->bh->b_data : ei->i_data;
447 __le32 *p;
Mingming Cao43d23f92006-06-25 05:48:07 -0700448 ext3_fsblk_t bg_start;
449 ext3_grpblk_t colour;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700450
451 /* Try to find previous block */
Andrew Mortond6859bf2006-03-26 01:38:03 -0800452 for (p = ind->p - 1; p >= start; p--) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700453 if (*p)
454 return le32_to_cpu(*p);
Andrew Mortond6859bf2006-03-26 01:38:03 -0800455 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700456
457 /* No such thing, so let's try location of indirect block */
458 if (ind->bh)
459 return ind->bh->b_blocknr;
460
461 /*
Andrew Mortond6859bf2006-03-26 01:38:03 -0800462 * It is going to be referred to from the inode itself? OK, just put it
463 * into the same cylinder group then.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700464 */
Mingming Cao43d23f92006-06-25 05:48:07 -0700465 bg_start = ext3_group_first_block_no(inode->i_sb, ei->i_block_group);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700466 colour = (current->pid % 16) *
467 (EXT3_BLOCKS_PER_GROUP(inode->i_sb) / 16);
468 return bg_start + colour;
469}
470
471/**
Benoit Boissinot1cc8dcf2008-04-21 22:45:55 +0000472 * ext3_find_goal - find a preferred place for allocation.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700473 * @inode: owner
474 * @block: block we want
Linus Torvalds1da177e2005-04-16 15:20:36 -0700475 * @partial: pointer to the last triple within a chain
Linus Torvalds1da177e2005-04-16 15:20:36 -0700476 *
Benoit Boissinot1cc8dcf2008-04-21 22:45:55 +0000477 * Normally this function find the preferred place for block allocation,
Akinobu Mitafb01bfd2008-02-06 01:40:16 -0800478 * returns it.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700479 */
480
Mingming Cao43d23f92006-06-25 05:48:07 -0700481static ext3_fsblk_t ext3_find_goal(struct inode *inode, long block,
Akinobu Mitafb01bfd2008-02-06 01:40:16 -0800482 Indirect *partial)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700483{
Andrew Mortond6859bf2006-03-26 01:38:03 -0800484 struct ext3_block_alloc_info *block_i;
485
486 block_i = EXT3_I(inode)->i_block_alloc_info;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700487
488 /*
489 * try the heuristic for sequential allocation,
490 * failing that at least try to get decent locality.
491 */
492 if (block_i && (block == block_i->last_alloc_logical_block + 1)
493 && (block_i->last_alloc_physical_block != 0)) {
Mingming Caofe55c452005-05-01 08:59:20 -0700494 return block_i->last_alloc_physical_block + 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700495 }
496
Mingming Caofe55c452005-05-01 08:59:20 -0700497 return ext3_find_near(inode, partial);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700498}
Andrew Mortond6859bf2006-03-26 01:38:03 -0800499
Mingming Caob47b2472006-03-26 01:37:56 -0800500/**
501 * ext3_blks_to_allocate: Look up the block map and count the number
502 * 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/**
539 * ext3_alloc_blocks: multiple allocate blocks needed for a branch
540 * @indirect_blks: the number of blocks need to allocate for indirect
541 * blocks
542 *
543 * @new_blocks: on return it will store the new block numbers for
544 * the indirect blocks(if needed) and the first direct block,
545 * @blks: on return it will store the total number of allocated
546 * direct blocks
547 */
548static int ext3_alloc_blocks(handle_t *handle, struct inode *inode,
Mingming Cao43d23f92006-06-25 05:48:07 -0700549 ext3_fsblk_t goal, int indirect_blks, int blks,
550 ext3_fsblk_t new_blocks[4], int *err)
Mingming Caob47b2472006-03-26 01:37:56 -0800551{
552 int target, i;
553 unsigned long count = 0;
554 int index = 0;
Mingming Cao43d23f92006-06-25 05:48:07 -0700555 ext3_fsblk_t current_block = 0;
Mingming Caob47b2472006-03-26 01:37:56 -0800556 int ret = 0;
557
558 /*
559 * Here we try to allocate the requested multiple blocks at once,
560 * on a best-effort basis.
561 * To build a branch, we should allocate blocks for
562 * the indirect blocks(if not allocated yet), and at least
563 * the first direct block of this branch. That's the
564 * minimum number of blocks need to allocate(required)
565 */
566 target = blks + indirect_blks;
567
568 while (1) {
569 count = target;
570 /* allocating blocks for indirect blocks and direct blocks */
Andrew Mortond6859bf2006-03-26 01:38:03 -0800571 current_block = ext3_new_blocks(handle,inode,goal,&count,err);
Mingming Caob47b2472006-03-26 01:37:56 -0800572 if (*err)
573 goto failed_out;
574
575 target -= count;
576 /* allocate blocks for indirect blocks */
577 while (index < indirect_blks && count) {
578 new_blocks[index++] = current_block++;
579 count--;
580 }
581
582 if (count > 0)
583 break;
584 }
585
586 /* save the new block number for the first direct block */
587 new_blocks[index] = current_block;
588
589 /* total number of blocks allocated for direct blocks */
590 ret = count;
591 *err = 0;
592 return ret;
593failed_out:
594 for (i = 0; i <index; i++)
595 ext3_free_blocks(handle, inode, new_blocks[i], 1);
596 return ret;
597}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700598
599/**
600 * ext3_alloc_branch - allocate and set up a chain of blocks.
601 * @inode: owner
Mingming Caob47b2472006-03-26 01:37:56 -0800602 * @indirect_blks: number of allocated indirect blocks
603 * @blks: number of allocated direct blocks
Linus Torvalds1da177e2005-04-16 15:20:36 -0700604 * @offsets: offsets (in the blocks) to store the pointers to next.
605 * @branch: place to store the chain in.
606 *
Mingming Caob47b2472006-03-26 01:37:56 -0800607 * This function allocates blocks, zeroes out all but the last one,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700608 * links them into chain and (if we are synchronous) writes them to disk.
609 * In other words, it prepares a branch that can be spliced onto the
610 * inode. It stores the information about that chain in the branch[], in
611 * the same format as ext3_get_branch() would do. We are calling it after
612 * we had read the existing part of chain and partial points to the last
613 * triple of that (one with zero ->key). Upon the exit we have the same
Glauber de Oliveira Costa5b116872005-10-30 15:02:48 -0800614 * picture as after the successful ext3_get_block(), except that in one
Linus Torvalds1da177e2005-04-16 15:20:36 -0700615 * place chain is disconnected - *branch->p is still zero (we did not
616 * set the last link), but branch->key contains the number that should
617 * be placed into *branch->p to fill that gap.
618 *
619 * If allocation fails we free all blocks we've allocated (and forget
620 * their buffer_heads) and return the error value the from failed
621 * ext3_alloc_block() (normally -ENOSPC). Otherwise we set the chain
622 * as described above and return 0.
623 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700624static int ext3_alloc_branch(handle_t *handle, struct inode *inode,
Mingming Cao43d23f92006-06-25 05:48:07 -0700625 int indirect_blks, int *blks, ext3_fsblk_t goal,
Mingming Caob47b2472006-03-26 01:37:56 -0800626 int *offsets, Indirect *branch)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700627{
628 int blocksize = inode->i_sb->s_blocksize;
Mingming Caob47b2472006-03-26 01:37:56 -0800629 int i, n = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700630 int err = 0;
Mingming Caob47b2472006-03-26 01:37:56 -0800631 struct buffer_head *bh;
632 int num;
Mingming Cao43d23f92006-06-25 05:48:07 -0700633 ext3_fsblk_t new_blocks[4];
634 ext3_fsblk_t current_block;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700635
Mingming Caob47b2472006-03-26 01:37:56 -0800636 num = ext3_alloc_blocks(handle, inode, goal, indirect_blks,
637 *blks, new_blocks, &err);
638 if (err)
639 return err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700640
Mingming Caob47b2472006-03-26 01:37:56 -0800641 branch[0].key = cpu_to_le32(new_blocks[0]);
642 /*
643 * metadata blocks and data blocks are allocated.
644 */
645 for (n = 1; n <= indirect_blks; n++) {
646 /*
647 * Get buffer_head for parent block, zero it out
648 * and set the pointer to new one, then send
649 * parent to disk.
650 */
651 bh = sb_getblk(inode->i_sb, new_blocks[n-1]);
652 branch[n].bh = bh;
653 lock_buffer(bh);
654 BUFFER_TRACE(bh, "call get_create_access");
655 err = ext3_journal_get_create_access(handle, bh);
656 if (err) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700657 unlock_buffer(bh);
Mingming Caob47b2472006-03-26 01:37:56 -0800658 brelse(bh);
659 goto failed;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700660 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700661
Mingming Caob47b2472006-03-26 01:37:56 -0800662 memset(bh->b_data, 0, blocksize);
663 branch[n].p = (__le32 *) bh->b_data + offsets[n];
664 branch[n].key = cpu_to_le32(new_blocks[n]);
665 *branch[n].p = branch[n].key;
666 if ( n == indirect_blks) {
667 current_block = new_blocks[n];
668 /*
669 * End of chain, update the last new metablock of
670 * the chain to point to the new allocated
671 * data blocks numbers
672 */
673 for (i=1; i < num; i++)
674 *(branch[n].p + i) = cpu_to_le32(++current_block);
675 }
676 BUFFER_TRACE(bh, "marking uptodate");
677 set_buffer_uptodate(bh);
678 unlock_buffer(bh);
679
680 BUFFER_TRACE(bh, "call ext3_journal_dirty_metadata");
681 err = ext3_journal_dirty_metadata(handle, bh);
682 if (err)
683 goto failed;
684 }
685 *blks = num;
686 return err;
687failed:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700688 /* Allocation failed, free what we already allocated */
Mingming Caob47b2472006-03-26 01:37:56 -0800689 for (i = 1; i <= n ; i++) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700690 BUFFER_TRACE(branch[i].bh, "call journal_forget");
691 ext3_journal_forget(handle, branch[i].bh);
692 }
Mingming Caob47b2472006-03-26 01:37:56 -0800693 for (i = 0; i <indirect_blks; i++)
694 ext3_free_blocks(handle, inode, new_blocks[i], 1);
695
696 ext3_free_blocks(handle, inode, new_blocks[i], num);
697
Linus Torvalds1da177e2005-04-16 15:20:36 -0700698 return err;
699}
700
701/**
Andrew Mortond6859bf2006-03-26 01:38:03 -0800702 * ext3_splice_branch - splice the allocated branch onto inode.
703 * @inode: owner
704 * @block: (logical) number of block we are adding
705 * @chain: chain of indirect blocks (with a missing link - see
706 * ext3_alloc_branch)
707 * @where: location of missing link
708 * @num: number of indirect blocks we are adding
709 * @blks: number of direct blocks we are adding
Linus Torvalds1da177e2005-04-16 15:20:36 -0700710 *
Andrew Mortond6859bf2006-03-26 01:38:03 -0800711 * This function fills the missing link and does all housekeeping needed in
712 * inode (->i_blocks, etc.). In case of success we end up with the full
713 * chain to new block and return 0.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700714 */
Andrew Mortond6859bf2006-03-26 01:38:03 -0800715static int ext3_splice_branch(handle_t *handle, struct inode *inode,
716 long block, Indirect *where, int num, int blks)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700717{
718 int i;
719 int err = 0;
Andrew Mortond6859bf2006-03-26 01:38:03 -0800720 struct ext3_block_alloc_info *block_i;
Mingming Cao43d23f92006-06-25 05:48:07 -0700721 ext3_fsblk_t current_block;
Jan Karafe8bc912009-10-16 19:26:15 +0200722 struct ext3_inode_info *ei = EXT3_I(inode);
Andrew Mortond6859bf2006-03-26 01:38:03 -0800723
Jan Karafe8bc912009-10-16 19:26:15 +0200724 block_i = ei->i_block_alloc_info;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700725 /*
726 * If we're splicing into a [td]indirect block (as opposed to the
727 * inode) then we need to get write access to the [td]indirect block
728 * before the splice.
729 */
730 if (where->bh) {
731 BUFFER_TRACE(where->bh, "get_write_access");
732 err = ext3_journal_get_write_access(handle, where->bh);
733 if (err)
734 goto err_out;
735 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700736 /* That's it */
737
738 *where->p = where->key;
Andrew Mortond6859bf2006-03-26 01:38:03 -0800739
740 /*
741 * Update the host buffer_head or inode to point to more just allocated
742 * direct blocks blocks
743 */
Mingming Caob47b2472006-03-26 01:37:56 -0800744 if (num == 0 && blks > 1) {
Mingming Cao5dea5172006-05-03 19:55:12 -0700745 current_block = le32_to_cpu(where->key) + 1;
Mingming Caob47b2472006-03-26 01:37:56 -0800746 for (i = 1; i < blks; i++)
747 *(where->p + i ) = cpu_to_le32(current_block++);
748 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700749
750 /*
751 * update the most recently allocated logical & physical block
752 * in i_block_alloc_info, to assist find the proper goal block for next
753 * allocation
754 */
755 if (block_i) {
Mingming Caob47b2472006-03-26 01:37:56 -0800756 block_i->last_alloc_logical_block = block + blks - 1;
Andrew Mortond6859bf2006-03-26 01:38:03 -0800757 block_i->last_alloc_physical_block =
Mingming Cao5dea5172006-05-03 19:55:12 -0700758 le32_to_cpu(where[num].key) + blks - 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700759 }
760
761 /* We are done with atomic stuff, now do the rest of housekeeping */
762
763 inode->i_ctime = CURRENT_TIME_SEC;
764 ext3_mark_inode_dirty(handle, inode);
Jan Karafe8bc912009-10-16 19:26:15 +0200765 /* ext3_mark_inode_dirty already updated i_sync_tid */
766 atomic_set(&ei->i_datasync_tid, handle->h_transaction->t_tid);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700767
768 /* had we spliced it onto indirect block? */
769 if (where->bh) {
770 /*
Andrew Mortond6859bf2006-03-26 01:38:03 -0800771 * If we spliced it onto an indirect block, we haven't
Linus Torvalds1da177e2005-04-16 15:20:36 -0700772 * altered the inode. Note however that if it is being spliced
773 * onto an indirect block at the very end of the file (the
774 * file is growing) then we *will* alter the inode to reflect
775 * the new i_size. But that is not done here - it is done in
776 * generic_commit_write->__mark_inode_dirty->ext3_dirty_inode.
777 */
778 jbd_debug(5, "splicing indirect only\n");
779 BUFFER_TRACE(where->bh, "call ext3_journal_dirty_metadata");
780 err = ext3_journal_dirty_metadata(handle, where->bh);
Mingming Caoae6ddcc2006-09-27 01:49:27 -0700781 if (err)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700782 goto err_out;
783 } else {
784 /*
785 * OK, we spliced it into the inode itself on a direct block.
786 * Inode was dirtied above.
787 */
788 jbd_debug(5, "splicing direct\n");
789 }
790 return err;
791
Linus Torvalds1da177e2005-04-16 15:20:36 -0700792err_out:
Mingming Caob47b2472006-03-26 01:37:56 -0800793 for (i = 1; i <= num; i++) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700794 BUFFER_TRACE(where[i].bh, "call journal_forget");
795 ext3_journal_forget(handle, where[i].bh);
Andrew Mortond6859bf2006-03-26 01:38:03 -0800796 ext3_free_blocks(handle,inode,le32_to_cpu(where[i-1].key),1);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700797 }
Mingming Caob47b2472006-03-26 01:37:56 -0800798 ext3_free_blocks(handle, inode, le32_to_cpu(where[num].key), blks);
799
Linus Torvalds1da177e2005-04-16 15:20:36 -0700800 return err;
801}
802
803/*
804 * Allocation strategy is simple: if we have to allocate something, we will
805 * have to go the whole way to leaf. So let's do it before attaching anything
806 * to tree, set linkage between the newborn blocks, write them if sync is
807 * required, recheck the path, free and repeat if check fails, otherwise
808 * set the last missing link (that will protect us from any truncate-generated
809 * removals - all blocks on the path are immune now) and possibly force the
810 * write on the parent block.
811 * That has a nice additional property: no special recovery from the failed
812 * allocations is needed - we simply release blocks and do not touch anything
813 * reachable from inode.
814 *
Andrew Mortond6859bf2006-03-26 01:38:03 -0800815 * `handle' can be NULL if create == 0.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700816 *
817 * The BKL may not be held on entry here. Be sure to take it early.
Mingming Cao89747d32006-03-26 01:37:55 -0800818 * return > 0, # of blocks mapped or allocated.
819 * return = 0, if plain lookup failed.
820 * return < 0, error case.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700821 */
Andrew Mortond6859bf2006-03-26 01:38:03 -0800822int ext3_get_blocks_handle(handle_t *handle, struct inode *inode,
823 sector_t iblock, unsigned long maxblocks,
824 struct buffer_head *bh_result,
Jan Kara43237b52009-05-20 18:41:58 +0200825 int create)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700826{
827 int err = -EIO;
828 int offsets[4];
829 Indirect chain[4];
830 Indirect *partial;
Mingming Cao43d23f92006-06-25 05:48:07 -0700831 ext3_fsblk_t goal;
Mingming Caob47b2472006-03-26 01:37:56 -0800832 int indirect_blks;
Mingming Cao89747d32006-03-26 01:37:55 -0800833 int blocks_to_boundary = 0;
834 int depth;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700835 struct ext3_inode_info *ei = EXT3_I(inode);
Mingming Cao89747d32006-03-26 01:37:55 -0800836 int count = 0;
Mingming Cao43d23f92006-06-25 05:48:07 -0700837 ext3_fsblk_t first_block = 0;
Mingming Cao89747d32006-03-26 01:37:55 -0800838
Linus Torvalds1da177e2005-04-16 15:20:36 -0700839
840 J_ASSERT(handle != NULL || create == 0);
Andrew Mortond6859bf2006-03-26 01:38:03 -0800841 depth = ext3_block_to_path(inode,iblock,offsets,&blocks_to_boundary);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700842
843 if (depth == 0)
844 goto out;
845
Linus Torvalds1da177e2005-04-16 15:20:36 -0700846 partial = ext3_get_branch(inode, depth, offsets, chain, &err);
847
848 /* Simplest case - block found, no allocation needed */
849 if (!partial) {
Mingming Cao5dea5172006-05-03 19:55:12 -0700850 first_block = le32_to_cpu(chain[depth - 1].key);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700851 clear_buffer_new(bh_result);
Mingming Cao89747d32006-03-26 01:37:55 -0800852 count++;
853 /*map more blocks*/
854 while (count < maxblocks && count <= blocks_to_boundary) {
Mingming Cao43d23f92006-06-25 05:48:07 -0700855 ext3_fsblk_t blk;
Mingming Cao5dea5172006-05-03 19:55:12 -0700856
Jan Karae8ef7aa2009-06-17 16:26:23 -0700857 if (!verify_chain(chain, chain + depth - 1)) {
Mingming Cao89747d32006-03-26 01:37:55 -0800858 /*
859 * Indirect block might be removed by
860 * truncate while we were reading it.
861 * Handling of that case: forget what we've
862 * got now. Flag the err as EAGAIN, so it
863 * will reread.
864 */
865 err = -EAGAIN;
866 count = 0;
867 break;
868 }
Mingming Cao5dea5172006-05-03 19:55:12 -0700869 blk = le32_to_cpu(*(chain[depth-1].p + count));
870
871 if (blk == first_block + count)
Mingming Cao89747d32006-03-26 01:37:55 -0800872 count++;
873 else
874 break;
875 }
876 if (err != -EAGAIN)
877 goto got_it;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700878 }
879
880 /* Next simple case - plain lookup or failed read of indirect block */
Mingming Caofe55c452005-05-01 08:59:20 -0700881 if (!create || err == -EIO)
882 goto cleanup;
883
Arjan van de Ven97461512006-03-23 03:00:42 -0800884 mutex_lock(&ei->truncate_mutex);
Mingming Caofe55c452005-05-01 08:59:20 -0700885
886 /*
887 * If the indirect block is missing while we are reading
888 * the chain(ext3_get_branch() returns -EAGAIN err), or
889 * if the chain has been changed after we grab the semaphore,
890 * (either because another process truncated this branch, or
891 * another get_block allocated this branch) re-grab the chain to see if
892 * the request block has been allocated or not.
893 *
894 * Since we already block the truncate/other get_block
895 * at this point, we will have the current copy of the chain when we
896 * splice the branch into the tree.
897 */
898 if (err == -EAGAIN || !verify_chain(chain, partial)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700899 while (partial > chain) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700900 brelse(partial->bh);
901 partial--;
902 }
Mingming Caofe55c452005-05-01 08:59:20 -0700903 partial = ext3_get_branch(inode, depth, offsets, chain, &err);
904 if (!partial) {
Mingming Cao89747d32006-03-26 01:37:55 -0800905 count++;
Arjan van de Ven97461512006-03-23 03:00:42 -0800906 mutex_unlock(&ei->truncate_mutex);
Mingming Caofe55c452005-05-01 08:59:20 -0700907 if (err)
908 goto cleanup;
909 clear_buffer_new(bh_result);
910 goto got_it;
911 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700912 }
913
914 /*
Mingming Caofe55c452005-05-01 08:59:20 -0700915 * Okay, we need to do block allocation. Lazily initialize the block
916 * allocation info here if necessary
917 */
918 if (S_ISREG(inode->i_mode) && (!ei->i_block_alloc_info))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700919 ext3_init_block_alloc_info(inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700920
Akinobu Mitafb01bfd2008-02-06 01:40:16 -0800921 goal = ext3_find_goal(inode, iblock, partial);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700922
Mingming Caob47b2472006-03-26 01:37:56 -0800923 /* the number of blocks need to allocate for [d,t]indirect blocks */
924 indirect_blks = (chain + depth) - partial - 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700925
926 /*
Mingming Caob47b2472006-03-26 01:37:56 -0800927 * Next look up the indirect map to count the totoal number of
928 * direct blocks to allocate for this branch.
929 */
930 count = ext3_blks_to_allocate(partial, indirect_blks,
931 maxblocks, blocks_to_boundary);
932 /*
Linus Torvalds1da177e2005-04-16 15:20:36 -0700933 * Block out ext3_truncate while we alter the tree
934 */
Mingming Caob47b2472006-03-26 01:37:56 -0800935 err = ext3_alloc_branch(handle, inode, indirect_blks, &count, goal,
Mingming Caofe55c452005-05-01 08:59:20 -0700936 offsets + (partial - chain), partial);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700937
Mingming Caofe55c452005-05-01 08:59:20 -0700938 /*
939 * The ext3_splice_branch call will free and forget any buffers
Linus Torvalds1da177e2005-04-16 15:20:36 -0700940 * on the new chain if there is a failure, but that risks using
941 * up transaction credits, especially for bitmaps where the
942 * credits cannot be returned. Can we handle this somehow? We
Mingming Caofe55c452005-05-01 08:59:20 -0700943 * may need to return -EAGAIN upwards in the worst case. --sct
944 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700945 if (!err)
Mingming Caob47b2472006-03-26 01:37:56 -0800946 err = ext3_splice_branch(handle, inode, iblock,
947 partial, indirect_blks, count);
Arjan van de Ven97461512006-03-23 03:00:42 -0800948 mutex_unlock(&ei->truncate_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700949 if (err)
950 goto cleanup;
951
952 set_buffer_new(bh_result);
Mingming Caofe55c452005-05-01 08:59:20 -0700953got_it:
954 map_bh(bh_result, inode->i_sb, le32_to_cpu(chain[depth-1].key));
Suparna Bhattacharya20acaa12006-09-16 12:15:58 -0700955 if (count > blocks_to_boundary)
Mingming Caofe55c452005-05-01 08:59:20 -0700956 set_buffer_boundary(bh_result);
Mingming Cao89747d32006-03-26 01:37:55 -0800957 err = count;
Mingming Caofe55c452005-05-01 08:59:20 -0700958 /* Clean up and exit */
959 partial = chain + depth - 1; /* the whole chain */
960cleanup:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700961 while (partial > chain) {
Mingming Caofe55c452005-05-01 08:59:20 -0700962 BUFFER_TRACE(partial->bh, "call brelse");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700963 brelse(partial->bh);
964 partial--;
965 }
Mingming Caofe55c452005-05-01 08:59:20 -0700966 BUFFER_TRACE(bh_result, "returned");
967out:
968 return err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700969}
970
Jan Karabd1939d2008-02-06 01:40:21 -0800971/* Maximum number of blocks we map for direct IO at once. */
972#define DIO_MAX_BLOCKS 4096
973/*
974 * Number of credits we need for writing DIO_MAX_BLOCKS:
975 * We need sb + group descriptor + bitmap + inode -> 4
976 * For B blocks with A block pointers per block we need:
977 * 1 (triple ind.) + (B/A/A + 2) (doubly ind.) + (B/A + 2) (indirect).
978 * If we plug in 4096 for B and 256 for A (for 1KB block size), we get 25.
979 */
980#define DIO_CREDITS 25
Linus Torvalds1da177e2005-04-16 15:20:36 -0700981
Badari Pulavartyf91a2ad2006-03-26 01:38:04 -0800982static int ext3_get_block(struct inode *inode, sector_t iblock,
983 struct buffer_head *bh_result, int create)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700984{
Dmitriy Monakhov3e4fdaf2007-02-10 01:46:35 -0800985 handle_t *handle = ext3_journal_current_handle();
Jan Karabd1939d2008-02-06 01:40:21 -0800986 int ret = 0, started = 0;
Badari Pulavarty1d8fa7a2006-03-26 01:38:02 -0800987 unsigned max_blocks = bh_result->b_size >> inode->i_blkbits;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700988
Jan Karabd1939d2008-02-06 01:40:21 -0800989 if (create && !handle) { /* Direct IO write... */
990 if (max_blocks > DIO_MAX_BLOCKS)
991 max_blocks = DIO_MAX_BLOCKS;
992 handle = ext3_journal_start(inode, DIO_CREDITS +
Dmitry Monakhovc4590012009-12-09 03:05:30 +0300993 EXT3_MAXQUOTAS_TRANS_BLOCKS(inode->i_sb));
Jan Karabd1939d2008-02-06 01:40:21 -0800994 if (IS_ERR(handle)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700995 ret = PTR_ERR(handle);
Jan Karabd1939d2008-02-06 01:40:21 -0800996 goto out;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700997 }
Jan Karabd1939d2008-02-06 01:40:21 -0800998 started = 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700999 }
1000
Jan Karabd1939d2008-02-06 01:40:21 -08001001 ret = ext3_get_blocks_handle(handle, inode, iblock,
Jan Kara43237b52009-05-20 18:41:58 +02001002 max_blocks, bh_result, create);
Jan Karabd1939d2008-02-06 01:40:21 -08001003 if (ret > 0) {
1004 bh_result->b_size = (ret << inode->i_blkbits);
1005 ret = 0;
Mingming Cao89747d32006-03-26 01:37:55 -08001006 }
Jan Karabd1939d2008-02-06 01:40:21 -08001007 if (started)
1008 ext3_journal_stop(handle);
1009out:
Linus Torvalds1da177e2005-04-16 15:20:36 -07001010 return ret;
1011}
1012
Josef Bacik68c9d702008-10-03 17:32:43 -04001013int ext3_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
1014 u64 start, u64 len)
1015{
1016 return generic_block_fiemap(inode, fieinfo, start, len,
1017 ext3_get_block);
1018}
1019
Linus Torvalds1da177e2005-04-16 15:20:36 -07001020/*
1021 * `handle' can be NULL if create is zero
1022 */
Andrew Mortond6859bf2006-03-26 01:38:03 -08001023struct buffer_head *ext3_getblk(handle_t *handle, struct inode *inode,
1024 long block, int create, int *errp)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001025{
1026 struct buffer_head dummy;
1027 int fatal = 0, err;
1028
1029 J_ASSERT(handle != NULL || create == 0);
1030
1031 dummy.b_state = 0;
1032 dummy.b_blocknr = -1000;
1033 buffer_trace_init(&dummy.b_history);
Mingming Cao89747d32006-03-26 01:37:55 -08001034 err = ext3_get_blocks_handle(handle, inode, block, 1,
Jan Kara43237b52009-05-20 18:41:58 +02001035 &dummy, create);
Badari Pulavarty3665d0e2006-09-08 09:48:21 -07001036 /*
1037 * ext3_get_blocks_handle() returns number of blocks
1038 * mapped. 0 in case of a HOLE.
1039 */
1040 if (err > 0) {
1041 if (err > 1)
1042 WARN_ON(1);
Mingming Cao89747d32006-03-26 01:37:55 -08001043 err = 0;
Mingming Cao89747d32006-03-26 01:37:55 -08001044 }
1045 *errp = err;
1046 if (!err && buffer_mapped(&dummy)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001047 struct buffer_head *bh;
1048 bh = sb_getblk(inode->i_sb, dummy.b_blocknr);
Glauber de Oliveira Costa2973dfd2005-10-30 15:03:05 -08001049 if (!bh) {
1050 *errp = -EIO;
1051 goto err;
1052 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001053 if (buffer_new(&dummy)) {
1054 J_ASSERT(create != 0);
Stephen Hemmingerc80544d2007-10-18 03:07:05 -07001055 J_ASSERT(handle != NULL);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001056
Andrew Mortond6859bf2006-03-26 01:38:03 -08001057 /*
1058 * Now that we do not always journal data, we should
1059 * keep in mind whether this should always journal the
1060 * new buffer as metadata. For now, regular file
1061 * writes use ext3_get_block instead, so it's not a
1062 * problem.
1063 */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001064 lock_buffer(bh);
1065 BUFFER_TRACE(bh, "call get_create_access");
1066 fatal = ext3_journal_get_create_access(handle, bh);
1067 if (!fatal && !buffer_uptodate(bh)) {
Andrew Mortond6859bf2006-03-26 01:38:03 -08001068 memset(bh->b_data,0,inode->i_sb->s_blocksize);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001069 set_buffer_uptodate(bh);
1070 }
1071 unlock_buffer(bh);
1072 BUFFER_TRACE(bh, "call ext3_journal_dirty_metadata");
1073 err = ext3_journal_dirty_metadata(handle, bh);
1074 if (!fatal)
1075 fatal = err;
1076 } else {
1077 BUFFER_TRACE(bh, "not a new buffer");
1078 }
1079 if (fatal) {
1080 *errp = fatal;
1081 brelse(bh);
1082 bh = NULL;
1083 }
1084 return bh;
1085 }
Glauber de Oliveira Costa2973dfd2005-10-30 15:03:05 -08001086err:
Linus Torvalds1da177e2005-04-16 15:20:36 -07001087 return NULL;
1088}
1089
Andrew Mortond6859bf2006-03-26 01:38:03 -08001090struct buffer_head *ext3_bread(handle_t *handle, struct inode *inode,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001091 int block, int create, int *err)
1092{
1093 struct buffer_head * bh;
1094
1095 bh = ext3_getblk(handle, inode, block, create, err);
1096 if (!bh)
1097 return bh;
1098 if (buffer_uptodate(bh))
1099 return bh;
Jens Axboecaa38fb2006-07-23 01:41:26 +02001100 ll_rw_block(READ_META, 1, &bh);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001101 wait_on_buffer(bh);
1102 if (buffer_uptodate(bh))
1103 return bh;
1104 put_bh(bh);
1105 *err = -EIO;
1106 return NULL;
1107}
1108
1109static int walk_page_buffers( handle_t *handle,
1110 struct buffer_head *head,
1111 unsigned from,
1112 unsigned to,
1113 int *partial,
1114 int (*fn)( handle_t *handle,
1115 struct buffer_head *bh))
1116{
1117 struct buffer_head *bh;
1118 unsigned block_start, block_end;
1119 unsigned blocksize = head->b_size;
1120 int err, ret = 0;
1121 struct buffer_head *next;
1122
1123 for ( bh = head, block_start = 0;
1124 ret == 0 && (bh != head || !block_start);
Dave Kleikampe9ad5622006-09-27 01:49:35 -07001125 block_start = block_end, bh = next)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001126 {
1127 next = bh->b_this_page;
1128 block_end = block_start + blocksize;
1129 if (block_end <= from || block_start >= to) {
1130 if (partial && !buffer_uptodate(bh))
1131 *partial = 1;
1132 continue;
1133 }
1134 err = (*fn)(handle, bh);
1135 if (!ret)
1136 ret = err;
1137 }
1138 return ret;
1139}
1140
1141/*
1142 * To preserve ordering, it is essential that the hole instantiation and
1143 * the data write be encapsulated in a single transaction. We cannot
1144 * close off a transaction and start a new one between the ext3_get_block()
1145 * and the commit_write(). So doing the journal_start at the start of
1146 * prepare_write() is the right place.
1147 *
1148 * Also, this function can nest inside ext3_writepage() ->
1149 * block_write_full_page(). In that case, we *know* that ext3_writepage()
1150 * has generated enough buffer credits to do the whole page. So we won't
1151 * block on the journal in that case, which is good, because the caller may
1152 * be PF_MEMALLOC.
1153 *
1154 * By accident, ext3 can be reentered when a transaction is open via
1155 * quota file writes. If we were to commit the transaction while thus
1156 * reentered, there can be a deadlock - we would be holding a quota
1157 * lock, and the commit would never complete if another thread had a
1158 * transaction open and was blocking on the quota lock - a ranking
1159 * violation.
1160 *
1161 * So what we do is to rely on the fact that journal_stop/journal_start
1162 * will _not_ run commit under these circumstances because handle->h_ref
1163 * is elevated. We'll still have enough credits for the tiny quotafile
Mingming Caoae6ddcc2006-09-27 01:49:27 -07001164 * write.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001165 */
Andrew Mortond6859bf2006-03-26 01:38:03 -08001166static int do_journal_get_write_access(handle_t *handle,
1167 struct buffer_head *bh)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001168{
Jan Kara5f11e6a2010-08-05 12:38:26 +02001169 int dirty = buffer_dirty(bh);
1170 int ret;
1171
Linus Torvalds1da177e2005-04-16 15:20:36 -07001172 if (!buffer_mapped(bh) || buffer_freed(bh))
1173 return 0;
Jan Kara5f11e6a2010-08-05 12:38:26 +02001174 /*
1175 * __block_prepare_write() could have dirtied some buffers. Clean
1176 * the dirty bit as jbd2_journal_get_write_access() could complain
1177 * otherwise about fs integrity issues. Setting of the dirty bit
1178 * by __block_prepare_write() isn't a real problem here as we clear
1179 * the bit before releasing a page lock and thus writeback cannot
1180 * ever write the buffer.
1181 */
1182 if (dirty)
1183 clear_buffer_dirty(bh);
1184 ret = ext3_journal_get_write_access(handle, bh);
1185 if (!ret && dirty)
1186 ret = ext3_journal_dirty_metadata(handle, bh);
1187 return ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001188}
1189
Jan Kara68eb3db2009-12-01 16:53:06 +01001190/*
1191 * Truncate blocks that were not used by write. We have to truncate the
1192 * pagecache as well so that corresponding buffers get properly unmapped.
1193 */
1194static void ext3_truncate_failed_write(struct inode *inode)
1195{
1196 truncate_inode_pages(inode->i_mapping, inode->i_size);
1197 ext3_truncate(inode);
1198}
1199
Nick Pigginf4fc66a2007-10-16 01:25:05 -07001200static int ext3_write_begin(struct file *file, struct address_space *mapping,
1201 loff_t pos, unsigned len, unsigned flags,
1202 struct page **pagep, void **fsdata)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001203{
Nick Pigginf4fc66a2007-10-16 01:25:05 -07001204 struct inode *inode = mapping->host;
Jan Kara695f6ae2009-04-02 16:57:17 -07001205 int ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001206 handle_t *handle;
1207 int retries = 0;
Nick Pigginf4fc66a2007-10-16 01:25:05 -07001208 struct page *page;
1209 pgoff_t index;
1210 unsigned from, to;
Jan Kara695f6ae2009-04-02 16:57:17 -07001211 /* Reserve one block more for addition to orphan list in case
1212 * we allocate blocks but write fails for some reason */
1213 int needed_blocks = ext3_writepage_trans_blocks(inode) + 1;
Nick Pigginf4fc66a2007-10-16 01:25:05 -07001214
1215 index = pos >> PAGE_CACHE_SHIFT;
1216 from = pos & (PAGE_CACHE_SIZE - 1);
1217 to = from + len;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001218
1219retry:
Nick Piggin54566b22009-01-04 12:00:53 -08001220 page = grab_cache_page_write_begin(mapping, index, flags);
Nick Pigginf4fc66a2007-10-16 01:25:05 -07001221 if (!page)
1222 return -ENOMEM;
1223 *pagep = page;
1224
Linus Torvalds1da177e2005-04-16 15:20:36 -07001225 handle = ext3_journal_start(inode, needed_blocks);
Andrew Morton1aa9b4b2007-04-01 23:49:43 -07001226 if (IS_ERR(handle)) {
Nick Pigginf4fc66a2007-10-16 01:25:05 -07001227 unlock_page(page);
1228 page_cache_release(page);
Andrew Morton1aa9b4b2007-04-01 23:49:43 -07001229 ret = PTR_ERR(handle);
1230 goto out;
1231 }
Christoph Hellwig6e1db882010-06-04 11:29:57 +02001232 ret = __block_write_begin(page, pos, len, ext3_get_block);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001233 if (ret)
Nick Pigginf4fc66a2007-10-16 01:25:05 -07001234 goto write_begin_failed;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001235
1236 if (ext3_should_journal_data(inode)) {
1237 ret = walk_page_buffers(handle, page_buffers(page),
1238 from, to, NULL, do_journal_get_write_access);
1239 }
Nick Pigginf4fc66a2007-10-16 01:25:05 -07001240write_begin_failed:
1241 if (ret) {
Aneesh Kumar K.V5ec8b752008-10-18 20:28:00 -07001242 /*
1243 * block_write_begin may have instantiated a few blocks
1244 * outside i_size. Trim these off again. Don't need
1245 * i_size_read because we hold i_mutex.
Jan Kara695f6ae2009-04-02 16:57:17 -07001246 *
1247 * Add inode to orphan list in case we crash before truncate
Jan Kara9eaaa2d2009-07-13 20:26:52 +02001248 * finishes. Do this only if ext3_can_truncate() agrees so
1249 * that orphan processing code is happy.
Aneesh Kumar K.V5ec8b752008-10-18 20:28:00 -07001250 */
Jan Kara9eaaa2d2009-07-13 20:26:52 +02001251 if (pos + len > inode->i_size && ext3_can_truncate(inode))
Jan Kara695f6ae2009-04-02 16:57:17 -07001252 ext3_orphan_add(handle, inode);
1253 ext3_journal_stop(handle);
1254 unlock_page(page);
1255 page_cache_release(page);
1256 if (pos + len > inode->i_size)
Jan Kara68eb3db2009-12-01 16:53:06 +01001257 ext3_truncate_failed_write(inode);
Nick Pigginf4fc66a2007-10-16 01:25:05 -07001258 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001259 if (ret == -ENOSPC && ext3_should_retry_alloc(inode->i_sb, &retries))
1260 goto retry;
Andrew Morton1aa9b4b2007-04-01 23:49:43 -07001261out:
Linus Torvalds1da177e2005-04-16 15:20:36 -07001262 return ret;
1263}
1264
Nick Pigginf4fc66a2007-10-16 01:25:05 -07001265
Andrew Mortond6859bf2006-03-26 01:38:03 -08001266int ext3_journal_dirty_data(handle_t *handle, struct buffer_head *bh)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001267{
1268 int err = journal_dirty_data(handle, bh);
1269 if (err)
Harvey Harrisone05b6b52008-04-28 02:16:15 -07001270 ext3_journal_abort_handle(__func__, __func__,
Nick Pigginf4fc66a2007-10-16 01:25:05 -07001271 bh, handle, err);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001272 return err;
1273}
1274
Jan Kara695f6ae2009-04-02 16:57:17 -07001275/* For ordered writepage and write_end functions */
1276static int journal_dirty_data_fn(handle_t *handle, struct buffer_head *bh)
1277{
1278 /*
1279 * Write could have mapped the buffer but it didn't copy the data in
1280 * yet. So avoid filing such buffer into a transaction.
1281 */
1282 if (buffer_mapped(bh) && buffer_uptodate(bh))
1283 return ext3_journal_dirty_data(handle, bh);
1284 return 0;
1285}
1286
Nick Pigginf4fc66a2007-10-16 01:25:05 -07001287/* For write_end() in data=journal mode */
1288static int write_end_fn(handle_t *handle, struct buffer_head *bh)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001289{
1290 if (!buffer_mapped(bh) || buffer_freed(bh))
1291 return 0;
1292 set_buffer_uptodate(bh);
1293 return ext3_journal_dirty_metadata(handle, bh);
1294}
1295
1296/*
Jan Kara695f6ae2009-04-02 16:57:17 -07001297 * This is nasty and subtle: ext3_write_begin() could have allocated blocks
1298 * for the whole page but later we failed to copy the data in. Update inode
1299 * size according to what we managed to copy. The rest is going to be
1300 * truncated in write_end function.
Nick Pigginf4fc66a2007-10-16 01:25:05 -07001301 */
Jan Kara695f6ae2009-04-02 16:57:17 -07001302static void update_file_sizes(struct inode *inode, loff_t pos, unsigned copied)
Nick Pigginf4fc66a2007-10-16 01:25:05 -07001303{
Jan Kara695f6ae2009-04-02 16:57:17 -07001304 /* What matters to us is i_disksize. We don't write i_size anywhere */
1305 if (pos + copied > inode->i_size)
1306 i_size_write(inode, pos + copied);
1307 if (pos + copied > EXT3_I(inode)->i_disksize) {
1308 EXT3_I(inode)->i_disksize = pos + copied;
Nick Pigginf4fc66a2007-10-16 01:25:05 -07001309 mark_inode_dirty(inode);
1310 }
Nick Pigginf4fc66a2007-10-16 01:25:05 -07001311}
1312
1313/*
Linus Torvalds1da177e2005-04-16 15:20:36 -07001314 * We need to pick up the new inode size which generic_commit_write gave us
1315 * `file' can be NULL - eg, when called from page_symlink().
1316 *
1317 * ext3 never places buffers on inode->i_mapping->private_list. metadata
1318 * buffers are managed internally.
1319 */
Nick Pigginf4fc66a2007-10-16 01:25:05 -07001320static int ext3_ordered_write_end(struct file *file,
1321 struct address_space *mapping,
1322 loff_t pos, unsigned len, unsigned copied,
1323 struct page *page, void *fsdata)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001324{
1325 handle_t *handle = ext3_journal_current_handle();
Nick Pigginf4fc66a2007-10-16 01:25:05 -07001326 struct inode *inode = file->f_mapping->host;
1327 unsigned from, to;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001328 int ret = 0, ret2;
1329
Jan Kara695f6ae2009-04-02 16:57:17 -07001330 copied = block_write_end(file, mapping, pos, len, copied, page, fsdata);
1331
Nick Pigginf4fc66a2007-10-16 01:25:05 -07001332 from = pos & (PAGE_CACHE_SIZE - 1);
Jan Kara695f6ae2009-04-02 16:57:17 -07001333 to = from + copied;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001334 ret = walk_page_buffers(handle, page_buffers(page),
Jan Kara695f6ae2009-04-02 16:57:17 -07001335 from, to, NULL, journal_dirty_data_fn);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001336
Jan Kara695f6ae2009-04-02 16:57:17 -07001337 if (ret == 0)
1338 update_file_sizes(inode, pos, copied);
1339 /*
1340 * There may be allocated blocks outside of i_size because
1341 * we failed to copy some data. Prepare for truncate.
1342 */
Jan Kara9eaaa2d2009-07-13 20:26:52 +02001343 if (pos + len > inode->i_size && ext3_can_truncate(inode))
Jan Kara695f6ae2009-04-02 16:57:17 -07001344 ext3_orphan_add(handle, inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001345 ret2 = ext3_journal_stop(handle);
1346 if (!ret)
1347 ret = ret2;
Nick Pigginf4fc66a2007-10-16 01:25:05 -07001348 unlock_page(page);
1349 page_cache_release(page);
1350
Jan Kara695f6ae2009-04-02 16:57:17 -07001351 if (pos + len > inode->i_size)
Jan Kara68eb3db2009-12-01 16:53:06 +01001352 ext3_truncate_failed_write(inode);
Nick Pigginf4fc66a2007-10-16 01:25:05 -07001353 return ret ? ret : copied;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001354}
1355
Nick Pigginf4fc66a2007-10-16 01:25:05 -07001356static int ext3_writeback_write_end(struct file *file,
1357 struct address_space *mapping,
1358 loff_t pos, unsigned len, unsigned copied,
1359 struct page *page, void *fsdata)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001360{
1361 handle_t *handle = ext3_journal_current_handle();
Nick Pigginf4fc66a2007-10-16 01:25:05 -07001362 struct inode *inode = file->f_mapping->host;
Jan Kara695f6ae2009-04-02 16:57:17 -07001363 int ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001364
Jan Kara695f6ae2009-04-02 16:57:17 -07001365 copied = block_write_end(file, mapping, pos, len, copied, page, fsdata);
1366 update_file_sizes(inode, pos, copied);
1367 /*
1368 * There may be allocated blocks outside of i_size because
1369 * we failed to copy some data. Prepare for truncate.
1370 */
Jan Kara9eaaa2d2009-07-13 20:26:52 +02001371 if (pos + len > inode->i_size && ext3_can_truncate(inode))
Jan Kara695f6ae2009-04-02 16:57:17 -07001372 ext3_orphan_add(handle, inode);
1373 ret = ext3_journal_stop(handle);
Nick Pigginf4fc66a2007-10-16 01:25:05 -07001374 unlock_page(page);
1375 page_cache_release(page);
1376
Jan Kara695f6ae2009-04-02 16:57:17 -07001377 if (pos + len > inode->i_size)
Jan Kara68eb3db2009-12-01 16:53:06 +01001378 ext3_truncate_failed_write(inode);
Nick Pigginf4fc66a2007-10-16 01:25:05 -07001379 return ret ? ret : copied;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001380}
1381
Nick Pigginf4fc66a2007-10-16 01:25:05 -07001382static int ext3_journalled_write_end(struct file *file,
1383 struct address_space *mapping,
1384 loff_t pos, unsigned len, unsigned copied,
1385 struct page *page, void *fsdata)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001386{
1387 handle_t *handle = ext3_journal_current_handle();
Nick Pigginf4fc66a2007-10-16 01:25:05 -07001388 struct inode *inode = mapping->host;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001389 int ret = 0, ret2;
1390 int partial = 0;
Nick Pigginf4fc66a2007-10-16 01:25:05 -07001391 unsigned from, to;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001392
Nick Pigginf4fc66a2007-10-16 01:25:05 -07001393 from = pos & (PAGE_CACHE_SIZE - 1);
1394 to = from + len;
1395
1396 if (copied < len) {
1397 if (!PageUptodate(page))
1398 copied = 0;
Jan Kara695f6ae2009-04-02 16:57:17 -07001399 page_zero_new_buffers(page, from + copied, to);
1400 to = from + copied;
Nick Pigginf4fc66a2007-10-16 01:25:05 -07001401 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001402
1403 ret = walk_page_buffers(handle, page_buffers(page), from,
Nick Pigginf4fc66a2007-10-16 01:25:05 -07001404 to, &partial, write_end_fn);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001405 if (!partial)
1406 SetPageUptodate(page);
Jan Kara695f6ae2009-04-02 16:57:17 -07001407
1408 if (pos + copied > inode->i_size)
1409 i_size_write(inode, pos + copied);
1410 /*
1411 * There may be allocated blocks outside of i_size because
1412 * we failed to copy some data. Prepare for truncate.
1413 */
Jan Kara9eaaa2d2009-07-13 20:26:52 +02001414 if (pos + len > inode->i_size && ext3_can_truncate(inode))
Jan Kara695f6ae2009-04-02 16:57:17 -07001415 ext3_orphan_add(handle, inode);
Jan Kara9df93932010-01-06 21:58:48 +01001416 ext3_set_inode_state(inode, EXT3_STATE_JDATA);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001417 if (inode->i_size > EXT3_I(inode)->i_disksize) {
1418 EXT3_I(inode)->i_disksize = inode->i_size;
1419 ret2 = ext3_mark_inode_dirty(handle, inode);
Mingming Caoae6ddcc2006-09-27 01:49:27 -07001420 if (!ret)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001421 ret = ret2;
1422 }
Nick Pigginf4fc66a2007-10-16 01:25:05 -07001423
Linus Torvalds1da177e2005-04-16 15:20:36 -07001424 ret2 = ext3_journal_stop(handle);
1425 if (!ret)
1426 ret = ret2;
Nick Pigginf4fc66a2007-10-16 01:25:05 -07001427 unlock_page(page);
1428 page_cache_release(page);
1429
Jan Kara695f6ae2009-04-02 16:57:17 -07001430 if (pos + len > inode->i_size)
Jan Kara68eb3db2009-12-01 16:53:06 +01001431 ext3_truncate_failed_write(inode);
Nick Pigginf4fc66a2007-10-16 01:25:05 -07001432 return ret ? ret : copied;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001433}
1434
Mingming Caoae6ddcc2006-09-27 01:49:27 -07001435/*
Linus Torvalds1da177e2005-04-16 15:20:36 -07001436 * bmap() is special. It gets used by applications such as lilo and by
1437 * the swapper to find the on-disk block of a specific piece of data.
1438 *
1439 * Naturally, this is dangerous if the block concerned is still in the
1440 * journal. If somebody makes a swapfile on an ext3 data-journaling
1441 * filesystem and enables swap, then they may get a nasty shock when the
1442 * data getting swapped to that swapfile suddenly gets overwritten by
1443 * the original zero's written out previously to the journal and
Mingming Caoae6ddcc2006-09-27 01:49:27 -07001444 * awaiting writeback in the kernel's buffer cache.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001445 *
1446 * So, if we see any bmap calls here on a modified, data-journaled file,
Mingming Caoae6ddcc2006-09-27 01:49:27 -07001447 * take extra steps to flush any blocks which might be in the cache.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001448 */
1449static sector_t ext3_bmap(struct address_space *mapping, sector_t block)
1450{
1451 struct inode *inode = mapping->host;
1452 journal_t *journal;
1453 int err;
1454
Jan Kara9df93932010-01-06 21:58:48 +01001455 if (ext3_test_inode_state(inode, EXT3_STATE_JDATA)) {
Mingming Caoae6ddcc2006-09-27 01:49:27 -07001456 /*
Linus Torvalds1da177e2005-04-16 15:20:36 -07001457 * This is a REALLY heavyweight approach, but the use of
1458 * bmap on dirty files is expected to be extremely rare:
1459 * only if we run lilo or swapon on a freshly made file
Mingming Caoae6ddcc2006-09-27 01:49:27 -07001460 * do we expect this to happen.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001461 *
1462 * (bmap requires CAP_SYS_RAWIO so this does not
1463 * represent an unprivileged user DOS attack --- we'd be
1464 * in trouble if mortal users could trigger this path at
Mingming Caoae6ddcc2006-09-27 01:49:27 -07001465 * will.)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001466 *
1467 * NB. EXT3_STATE_JDATA is not set on files other than
1468 * regular files. If somebody wants to bmap a directory
1469 * or symlink and gets confused because the buffer
1470 * hasn't yet been flushed to disk, they deserve
1471 * everything they get.
1472 */
1473
Jan Kara9df93932010-01-06 21:58:48 +01001474 ext3_clear_inode_state(inode, EXT3_STATE_JDATA);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001475 journal = EXT3_JOURNAL(inode);
1476 journal_lock_updates(journal);
1477 err = journal_flush(journal);
1478 journal_unlock_updates(journal);
1479
1480 if (err)
1481 return 0;
1482 }
1483
1484 return generic_block_bmap(mapping,block,ext3_get_block);
1485}
1486
1487static int bget_one(handle_t *handle, struct buffer_head *bh)
1488{
1489 get_bh(bh);
1490 return 0;
1491}
1492
1493static int bput_one(handle_t *handle, struct buffer_head *bh)
1494{
1495 put_bh(bh);
1496 return 0;
1497}
1498
Jan Kara9e80d402009-03-26 13:08:04 +01001499static int buffer_unmapped(handle_t *handle, struct buffer_head *bh)
1500{
1501 return !buffer_mapped(bh);
1502}
Jan Kara695f6ae2009-04-02 16:57:17 -07001503
Linus Torvalds1da177e2005-04-16 15:20:36 -07001504/*
1505 * Note that we always start a transaction even if we're not journalling
1506 * data. This is to preserve ordering: any hole instantiation within
1507 * __block_write_full_page -> ext3_get_block() should be journalled
1508 * along with the data so we don't crash and then get metadata which
1509 * refers to old data.
1510 *
1511 * In all journalling modes block_write_full_page() will start the I/O.
1512 *
1513 * Problem:
1514 *
1515 * ext3_writepage() -> kmalloc() -> __alloc_pages() -> page_launder() ->
1516 * ext3_writepage()
1517 *
1518 * Similar for:
1519 *
1520 * ext3_file_write() -> generic_file_write() -> __alloc_pages() -> ...
1521 *
1522 * Same applies to ext3_get_block(). We will deadlock on various things like
Arjan van de Ven97461512006-03-23 03:00:42 -08001523 * lock_journal and i_truncate_mutex.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001524 *
1525 * Setting PF_MEMALLOC here doesn't work - too many internal memory
1526 * allocations fail.
1527 *
1528 * 16May01: If we're reentered then journal_current_handle() will be
1529 * non-zero. We simply *return*.
1530 *
1531 * 1 July 2001: @@@ FIXME:
1532 * In journalled data mode, a data buffer may be metadata against the
1533 * current transaction. But the same file is part of a shared mapping
1534 * and someone does a writepage() on it.
1535 *
1536 * We will move the buffer onto the async_data list, but *after* it has
1537 * been dirtied. So there's a small window where we have dirty data on
1538 * BJ_Metadata.
1539 *
1540 * Note that this only applies to the last partial page in the file. The
1541 * bit which block_write_full_page() uses prepare/commit for. (That's
1542 * broken code anyway: it's wrong for msync()).
1543 *
1544 * It's a rare case: affects the final partial page, for journalled data
1545 * where the file is subject to bith write() and writepage() in the same
1546 * transction. To fix it we'll need a custom block_write_full_page().
1547 * We'll probably need that anyway for journalling writepage() output.
1548 *
1549 * We don't honour synchronous mounts for writepage(). That would be
1550 * disastrous. Any write() or metadata operation will sync the fs for
1551 * us.
1552 *
1553 * AKPM2: if all the page's buffers are mapped to disk and !data=journal,
1554 * we don't need to open a transaction here.
1555 */
1556static int ext3_ordered_writepage(struct page *page,
Andrew Mortond6859bf2006-03-26 01:38:03 -08001557 struct writeback_control *wbc)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001558{
1559 struct inode *inode = page->mapping->host;
1560 struct buffer_head *page_bufs;
1561 handle_t *handle = NULL;
1562 int ret = 0;
1563 int err;
1564
1565 J_ASSERT(PageLocked(page));
Dmitry Monakhov49792c82010-03-02 15:51:02 +03001566 WARN_ON_ONCE(IS_RDONLY(inode));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001567
1568 /*
1569 * We give up here if we're reentered, because it might be for a
1570 * different filesystem.
1571 */
1572 if (ext3_journal_current_handle())
1573 goto out_fail;
1574
Jan Kara9e80d402009-03-26 13:08:04 +01001575 if (!page_has_buffers(page)) {
1576 create_empty_buffers(page, inode->i_sb->s_blocksize,
1577 (1 << BH_Dirty)|(1 << BH_Uptodate));
Jan Kara430db322009-04-07 18:25:01 -04001578 page_bufs = page_buffers(page);
1579 } else {
1580 page_bufs = page_buffers(page);
1581 if (!walk_page_buffers(NULL, page_bufs, 0, PAGE_CACHE_SIZE,
1582 NULL, buffer_unmapped)) {
1583 /* Provide NULL get_block() to catch bugs if buffers
1584 * weren't really mapped */
1585 return block_write_full_page(page, NULL, wbc);
1586 }
Jan Kara9e80d402009-03-26 13:08:04 +01001587 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001588 handle = ext3_journal_start(inode, ext3_writepage_trans_blocks(inode));
1589
1590 if (IS_ERR(handle)) {
1591 ret = PTR_ERR(handle);
1592 goto out_fail;
1593 }
1594
Linus Torvalds1da177e2005-04-16 15:20:36 -07001595 walk_page_buffers(handle, page_bufs, 0,
1596 PAGE_CACHE_SIZE, NULL, bget_one);
1597
1598 ret = block_write_full_page(page, ext3_get_block, wbc);
1599
1600 /*
1601 * The page can become unlocked at any point now, and
1602 * truncate can then come in and change things. So we
1603 * can't touch *page from now on. But *page_bufs is
1604 * safe due to elevated refcount.
1605 */
1606
1607 /*
Mingming Caoae6ddcc2006-09-27 01:49:27 -07001608 * And attach them to the current transaction. But only if
Linus Torvalds1da177e2005-04-16 15:20:36 -07001609 * block_write_full_page() succeeded. Otherwise they are unmapped,
1610 * and generally junk.
1611 */
1612 if (ret == 0) {
1613 err = walk_page_buffers(handle, page_bufs, 0, PAGE_CACHE_SIZE,
1614 NULL, journal_dirty_data_fn);
1615 if (!ret)
1616 ret = err;
1617 }
1618 walk_page_buffers(handle, page_bufs, 0,
1619 PAGE_CACHE_SIZE, NULL, bput_one);
1620 err = ext3_journal_stop(handle);
1621 if (!ret)
1622 ret = err;
1623 return ret;
1624
1625out_fail:
1626 redirty_page_for_writepage(wbc, page);
1627 unlock_page(page);
1628 return ret;
1629}
1630
Linus Torvalds1da177e2005-04-16 15:20:36 -07001631static int ext3_writeback_writepage(struct page *page,
1632 struct writeback_control *wbc)
1633{
1634 struct inode *inode = page->mapping->host;
1635 handle_t *handle = NULL;
1636 int ret = 0;
1637 int err;
1638
Dmitry Monakhov49792c82010-03-02 15:51:02 +03001639 J_ASSERT(PageLocked(page));
1640 WARN_ON_ONCE(IS_RDONLY(inode));
1641
Linus Torvalds1da177e2005-04-16 15:20:36 -07001642 if (ext3_journal_current_handle())
1643 goto out_fail;
1644
Jan Kara430db322009-04-07 18:25:01 -04001645 if (page_has_buffers(page)) {
1646 if (!walk_page_buffers(NULL, page_buffers(page), 0,
1647 PAGE_CACHE_SIZE, NULL, buffer_unmapped)) {
1648 /* Provide NULL get_block() to catch bugs if buffers
1649 * weren't really mapped */
1650 return block_write_full_page(page, NULL, wbc);
1651 }
1652 }
1653
Linus Torvalds1da177e2005-04-16 15:20:36 -07001654 handle = ext3_journal_start(inode, ext3_writepage_trans_blocks(inode));
1655 if (IS_ERR(handle)) {
1656 ret = PTR_ERR(handle);
1657 goto out_fail;
1658 }
1659
Christoph Hellwig4c4d3902010-06-07 10:20:39 +02001660 ret = block_write_full_page(page, ext3_get_block, wbc);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001661
1662 err = ext3_journal_stop(handle);
1663 if (!ret)
1664 ret = err;
1665 return ret;
1666
1667out_fail:
1668 redirty_page_for_writepage(wbc, page);
1669 unlock_page(page);
1670 return ret;
1671}
1672
1673static int ext3_journalled_writepage(struct page *page,
1674 struct writeback_control *wbc)
1675{
1676 struct inode *inode = page->mapping->host;
1677 handle_t *handle = NULL;
1678 int ret = 0;
1679 int err;
1680
Dmitry Monakhov49792c82010-03-02 15:51:02 +03001681 J_ASSERT(PageLocked(page));
1682 WARN_ON_ONCE(IS_RDONLY(inode));
1683
Linus Torvalds1da177e2005-04-16 15:20:36 -07001684 if (ext3_journal_current_handle())
1685 goto no_write;
1686
1687 handle = ext3_journal_start(inode, ext3_writepage_trans_blocks(inode));
1688 if (IS_ERR(handle)) {
1689 ret = PTR_ERR(handle);
1690 goto no_write;
1691 }
1692
1693 if (!page_has_buffers(page) || PageChecked(page)) {
1694 /*
1695 * It's mmapped pagecache. Add buffers and journal it. There
1696 * doesn't seem much point in redirtying the page here.
1697 */
1698 ClearPageChecked(page);
1699 ret = block_prepare_write(page, 0, PAGE_CACHE_SIZE,
1700 ext3_get_block);
Denis Lunevab4eb432005-11-13 16:07:17 -08001701 if (ret != 0) {
1702 ext3_journal_stop(handle);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001703 goto out_unlock;
Denis Lunevab4eb432005-11-13 16:07:17 -08001704 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001705 ret = walk_page_buffers(handle, page_buffers(page), 0,
1706 PAGE_CACHE_SIZE, NULL, do_journal_get_write_access);
1707
1708 err = walk_page_buffers(handle, page_buffers(page), 0,
Nick Pigginf4fc66a2007-10-16 01:25:05 -07001709 PAGE_CACHE_SIZE, NULL, write_end_fn);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001710 if (ret == 0)
1711 ret = err;
Jan Kara9df93932010-01-06 21:58:48 +01001712 ext3_set_inode_state(inode, EXT3_STATE_JDATA);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001713 unlock_page(page);
1714 } else {
1715 /*
1716 * It may be a page full of checkpoint-mode buffers. We don't
1717 * really know unless we go poke around in the buffer_heads.
1718 * But block_write_full_page will do the right thing.
1719 */
1720 ret = block_write_full_page(page, ext3_get_block, wbc);
1721 }
1722 err = ext3_journal_stop(handle);
1723 if (!ret)
1724 ret = err;
1725out:
1726 return ret;
1727
1728no_write:
1729 redirty_page_for_writepage(wbc, page);
1730out_unlock:
1731 unlock_page(page);
1732 goto out;
1733}
1734
1735static int ext3_readpage(struct file *file, struct page *page)
1736{
1737 return mpage_readpage(page, ext3_get_block);
1738}
1739
1740static int
1741ext3_readpages(struct file *file, struct address_space *mapping,
1742 struct list_head *pages, unsigned nr_pages)
1743{
1744 return mpage_readpages(mapping, pages, nr_pages, ext3_get_block);
1745}
1746
NeilBrown2ff28e22006-03-26 01:37:18 -08001747static void ext3_invalidatepage(struct page *page, unsigned long offset)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001748{
1749 journal_t *journal = EXT3_JOURNAL(page->mapping->host);
1750
1751 /*
1752 * If it's a full truncate we just forget about the pending dirtying
1753 */
1754 if (offset == 0)
1755 ClearPageChecked(page);
1756
NeilBrown2ff28e22006-03-26 01:37:18 -08001757 journal_invalidatepage(journal, page, offset);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001758}
1759
Al Viro27496a82005-10-21 03:20:48 -04001760static int ext3_releasepage(struct page *page, gfp_t wait)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001761{
1762 journal_t *journal = EXT3_JOURNAL(page->mapping->host);
1763
1764 WARN_ON(PageChecked(page));
1765 if (!page_has_buffers(page))
1766 return 0;
1767 return journal_try_to_free_buffers(journal, page, wait);
1768}
1769
1770/*
1771 * If the O_DIRECT write will extend the file then add this inode to the
1772 * orphan list. So recovery will truncate it back to the original size
1773 * if the machine crashes during the write.
1774 *
1775 * If the O_DIRECT write is intantiating holes inside i_size and the machine
Jan Karabd1939d2008-02-06 01:40:21 -08001776 * crashes then stale disk data _may_ be exposed inside the file. But current
1777 * VFS code falls back into buffered path in that case so we are safe.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001778 */
1779static ssize_t ext3_direct_IO(int rw, struct kiocb *iocb,
1780 const struct iovec *iov, loff_t offset,
1781 unsigned long nr_segs)
1782{
1783 struct file *file = iocb->ki_filp;
1784 struct inode *inode = file->f_mapping->host;
1785 struct ext3_inode_info *ei = EXT3_I(inode);
Jan Karabd1939d2008-02-06 01:40:21 -08001786 handle_t *handle;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001787 ssize_t ret;
1788 int orphan = 0;
1789 size_t count = iov_length(iov, nr_segs);
Eric Sandeenea0174a2009-10-12 21:34:27 -05001790 int retries = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001791
1792 if (rw == WRITE) {
1793 loff_t final_size = offset + count;
1794
Linus Torvalds1da177e2005-04-16 15:20:36 -07001795 if (final_size > inode->i_size) {
Jan Karabd1939d2008-02-06 01:40:21 -08001796 /* Credits for sb + inode write */
1797 handle = ext3_journal_start(inode, 2);
1798 if (IS_ERR(handle)) {
1799 ret = PTR_ERR(handle);
1800 goto out;
1801 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001802 ret = ext3_orphan_add(handle, inode);
Jan Karabd1939d2008-02-06 01:40:21 -08001803 if (ret) {
1804 ext3_journal_stop(handle);
1805 goto out;
1806 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001807 orphan = 1;
1808 ei->i_disksize = inode->i_size;
Jan Karabd1939d2008-02-06 01:40:21 -08001809 ext3_journal_stop(handle);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001810 }
1811 }
1812
Eric Sandeenea0174a2009-10-12 21:34:27 -05001813retry:
Mingming Caoae6ddcc2006-09-27 01:49:27 -07001814 ret = blockdev_direct_IO(rw, iocb, inode, inode->i_sb->s_bdev, iov,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001815 offset, nr_segs,
Badari Pulavartyf91a2ad2006-03-26 01:38:04 -08001816 ext3_get_block, NULL);
Christoph Hellwigeafdc7d2010-06-04 11:29:53 +02001817 /*
1818 * In case of error extending write may have instantiated a few
1819 * blocks outside i_size. Trim these off again.
1820 */
1821 if (unlikely((rw & WRITE) && ret < 0)) {
1822 loff_t isize = i_size_read(inode);
1823 loff_t end = offset + iov_length(iov, nr_segs);
1824
1825 if (end > isize)
1826 vmtruncate(inode, isize);
1827 }
Eric Sandeenea0174a2009-10-12 21:34:27 -05001828 if (ret == -ENOSPC && ext3_should_retry_alloc(inode->i_sb, &retries))
1829 goto retry;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001830
Jan Karabd1939d2008-02-06 01:40:21 -08001831 if (orphan) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001832 int err;
1833
Jan Karabd1939d2008-02-06 01:40:21 -08001834 /* Credits for sb + inode write */
1835 handle = ext3_journal_start(inode, 2);
1836 if (IS_ERR(handle)) {
1837 /* This is really bad luck. We've written the data
Jan Kara7eb49692010-03-01 14:02:37 +01001838 * but cannot extend i_size. Truncate allocated blocks
1839 * and pretend the write failed... */
1840 ext3_truncate(inode);
Jan Karabd1939d2008-02-06 01:40:21 -08001841 ret = PTR_ERR(handle);
1842 goto out;
1843 }
1844 if (inode->i_nlink)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001845 ext3_orphan_del(handle, inode);
Jan Karabd1939d2008-02-06 01:40:21 -08001846 if (ret > 0) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001847 loff_t end = offset + ret;
1848 if (end > inode->i_size) {
1849 ei->i_disksize = end;
1850 i_size_write(inode, end);
1851 /*
1852 * We're going to return a positive `ret'
1853 * here due to non-zero-length I/O, so there's
1854 * no way of reporting error returns from
1855 * ext3_mark_inode_dirty() to userspace. So
1856 * ignore it.
1857 */
1858 ext3_mark_inode_dirty(handle, inode);
1859 }
1860 }
1861 err = ext3_journal_stop(handle);
1862 if (ret == 0)
1863 ret = err;
1864 }
1865out:
1866 return ret;
1867}
1868
1869/*
1870 * Pages can be marked dirty completely asynchronously from ext3's journalling
1871 * activity. By filemap_sync_pte(), try_to_unmap_one(), etc. We cannot do
1872 * much here because ->set_page_dirty is called under VFS locks. The page is
1873 * not necessarily locked.
1874 *
1875 * We cannot just dirty the page and leave attached buffers clean, because the
1876 * buffers' dirty state is "definitive". We cannot just set the buffers dirty
1877 * or jbddirty because all the journalling code will explode.
1878 *
1879 * So what we do is to mark the page "pending dirty" and next time writepage
1880 * is called, propagate that into the buffers appropriately.
1881 */
1882static int ext3_journalled_set_page_dirty(struct page *page)
1883{
1884 SetPageChecked(page);
1885 return __set_page_dirty_nobuffers(page);
1886}
1887
Christoph Hellwigf5e54d62006-06-28 04:26:44 -07001888static const struct address_space_operations ext3_ordered_aops = {
Hisashi Hifumi8ab22b92008-07-28 15:46:36 -07001889 .readpage = ext3_readpage,
1890 .readpages = ext3_readpages,
1891 .writepage = ext3_ordered_writepage,
1892 .sync_page = block_sync_page,
1893 .write_begin = ext3_write_begin,
1894 .write_end = ext3_ordered_write_end,
1895 .bmap = ext3_bmap,
1896 .invalidatepage = ext3_invalidatepage,
1897 .releasepage = ext3_releasepage,
1898 .direct_IO = ext3_direct_IO,
1899 .migratepage = buffer_migrate_page,
1900 .is_partially_uptodate = block_is_partially_uptodate,
Andi Kleenaa261f52009-09-16 11:50:16 +02001901 .error_remove_page = generic_error_remove_page,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001902};
1903
Christoph Hellwigf5e54d62006-06-28 04:26:44 -07001904static const struct address_space_operations ext3_writeback_aops = {
Hisashi Hifumi8ab22b92008-07-28 15:46:36 -07001905 .readpage = ext3_readpage,
1906 .readpages = ext3_readpages,
1907 .writepage = ext3_writeback_writepage,
1908 .sync_page = block_sync_page,
1909 .write_begin = ext3_write_begin,
1910 .write_end = ext3_writeback_write_end,
1911 .bmap = ext3_bmap,
1912 .invalidatepage = ext3_invalidatepage,
1913 .releasepage = ext3_releasepage,
1914 .direct_IO = ext3_direct_IO,
1915 .migratepage = buffer_migrate_page,
1916 .is_partially_uptodate = block_is_partially_uptodate,
Andi Kleenaa261f52009-09-16 11:50:16 +02001917 .error_remove_page = generic_error_remove_page,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001918};
1919
Christoph Hellwigf5e54d62006-06-28 04:26:44 -07001920static const struct address_space_operations ext3_journalled_aops = {
Hisashi Hifumi8ab22b92008-07-28 15:46:36 -07001921 .readpage = ext3_readpage,
1922 .readpages = ext3_readpages,
1923 .writepage = ext3_journalled_writepage,
1924 .sync_page = block_sync_page,
1925 .write_begin = ext3_write_begin,
1926 .write_end = ext3_journalled_write_end,
1927 .set_page_dirty = ext3_journalled_set_page_dirty,
1928 .bmap = ext3_bmap,
1929 .invalidatepage = ext3_invalidatepage,
1930 .releasepage = ext3_releasepage,
1931 .is_partially_uptodate = block_is_partially_uptodate,
Andi Kleenaa261f52009-09-16 11:50:16 +02001932 .error_remove_page = generic_error_remove_page,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001933};
1934
1935void ext3_set_aops(struct inode *inode)
1936{
1937 if (ext3_should_order_data(inode))
1938 inode->i_mapping->a_ops = &ext3_ordered_aops;
1939 else if (ext3_should_writeback_data(inode))
1940 inode->i_mapping->a_ops = &ext3_writeback_aops;
1941 else
1942 inode->i_mapping->a_ops = &ext3_journalled_aops;
1943}
1944
1945/*
1946 * ext3_block_truncate_page() zeroes out a mapping from file offset `from'
1947 * up to the end of the block which corresponds to `from'.
1948 * This required during truncate. We need to physically zero the tail end
1949 * of that block so it doesn't yield old data if the file is later grown.
1950 */
1951static int ext3_block_truncate_page(handle_t *handle, struct page *page,
1952 struct address_space *mapping, loff_t from)
1953{
Mingming Cao43d23f92006-06-25 05:48:07 -07001954 ext3_fsblk_t index = from >> PAGE_CACHE_SHIFT;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001955 unsigned offset = from & (PAGE_CACHE_SIZE-1);
1956 unsigned blocksize, iblock, length, pos;
1957 struct inode *inode = mapping->host;
1958 struct buffer_head *bh;
1959 int err = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001960
1961 blocksize = inode->i_sb->s_blocksize;
1962 length = blocksize - (offset & (blocksize - 1));
1963 iblock = index << (PAGE_CACHE_SHIFT - inode->i_sb->s_blocksize_bits);
1964
Linus Torvalds1da177e2005-04-16 15:20:36 -07001965 if (!page_has_buffers(page))
1966 create_empty_buffers(page, blocksize, 0);
1967
1968 /* Find the buffer that contains "offset" */
1969 bh = page_buffers(page);
1970 pos = blocksize;
1971 while (offset >= pos) {
1972 bh = bh->b_this_page;
1973 iblock++;
1974 pos += blocksize;
1975 }
1976
1977 err = 0;
1978 if (buffer_freed(bh)) {
1979 BUFFER_TRACE(bh, "freed: skip");
1980 goto unlock;
1981 }
1982
1983 if (!buffer_mapped(bh)) {
1984 BUFFER_TRACE(bh, "unmapped");
1985 ext3_get_block(inode, iblock, bh, 0);
1986 /* unmapped? It's a hole - nothing to do */
1987 if (!buffer_mapped(bh)) {
1988 BUFFER_TRACE(bh, "still unmapped");
1989 goto unlock;
1990 }
1991 }
1992
1993 /* Ok, it's mapped. Make sure it's up-to-date */
1994 if (PageUptodate(page))
1995 set_buffer_uptodate(bh);
1996
1997 if (!buffer_uptodate(bh)) {
1998 err = -EIO;
1999 ll_rw_block(READ, 1, &bh);
2000 wait_on_buffer(bh);
2001 /* Uhhuh. Read error. Complain and punt. */
2002 if (!buffer_uptodate(bh))
2003 goto unlock;
2004 }
2005
2006 if (ext3_should_journal_data(inode)) {
2007 BUFFER_TRACE(bh, "get write access");
2008 err = ext3_journal_get_write_access(handle, bh);
2009 if (err)
2010 goto unlock;
2011 }
2012
Christoph Lametereebd2aa2008-02-04 22:28:29 -08002013 zero_user(page, offset, length);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002014 BUFFER_TRACE(bh, "zeroed end of block");
2015
2016 err = 0;
2017 if (ext3_should_journal_data(inode)) {
2018 err = ext3_journal_dirty_metadata(handle, bh);
2019 } else {
2020 if (ext3_should_order_data(inode))
2021 err = ext3_journal_dirty_data(handle, bh);
2022 mark_buffer_dirty(bh);
2023 }
2024
2025unlock:
2026 unlock_page(page);
2027 page_cache_release(page);
2028 return err;
2029}
2030
2031/*
2032 * Probably it should be a library function... search for first non-zero word
2033 * or memcmp with zero_page, whatever is better for particular architecture.
2034 * Linus?
2035 */
2036static inline int all_zeroes(__le32 *p, __le32 *q)
2037{
2038 while (p < q)
2039 if (*p++)
2040 return 0;
2041 return 1;
2042}
2043
2044/**
2045 * ext3_find_shared - find the indirect blocks for partial truncation.
2046 * @inode: inode in question
2047 * @depth: depth of the affected branch
2048 * @offsets: offsets of pointers in that branch (see ext3_block_to_path)
2049 * @chain: place to store the pointers to partial indirect blocks
2050 * @top: place to the (detached) top of branch
2051 *
2052 * This is a helper function used by ext3_truncate().
2053 *
2054 * When we do truncate() we may have to clean the ends of several
2055 * indirect blocks but leave the blocks themselves alive. Block is
2056 * partially truncated if some data below the new i_size is refered
2057 * from it (and it is on the path to the first completely truncated
2058 * data block, indeed). We have to free the top of that path along
2059 * with everything to the right of the path. Since no allocation
2060 * past the truncation point is possible until ext3_truncate()
2061 * finishes, we may safely do the latter, but top of branch may
2062 * require special attention - pageout below the truncation point
2063 * might try to populate it.
2064 *
2065 * We atomically detach the top of branch from the tree, store the
2066 * block number of its root in *@top, pointers to buffer_heads of
2067 * partially truncated blocks - in @chain[].bh and pointers to
2068 * their last elements that should not be removed - in
2069 * @chain[].p. Return value is the pointer to last filled element
2070 * of @chain.
2071 *
2072 * The work left to caller to do the actual freeing of subtrees:
2073 * a) free the subtree starting from *@top
2074 * b) free the subtrees whose roots are stored in
2075 * (@chain[i].p+1 .. end of @chain[i].bh->b_data)
2076 * c) free the subtrees growing from the inode past the @chain[0].
2077 * (no partially truncated stuff there). */
2078
Andrew Mortond6859bf2006-03-26 01:38:03 -08002079static Indirect *ext3_find_shared(struct inode *inode, int depth,
2080 int offsets[4], Indirect chain[4], __le32 *top)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002081{
2082 Indirect *partial, *p;
2083 int k, err;
2084
2085 *top = 0;
Uwe Kleine-Königbf48aab2009-10-28 20:11:03 +01002086 /* Make k index the deepest non-null offset + 1 */
Linus Torvalds1da177e2005-04-16 15:20:36 -07002087 for (k = depth; k > 1 && !offsets[k-1]; k--)
2088 ;
2089 partial = ext3_get_branch(inode, k, offsets, chain, &err);
2090 /* Writer: pointers */
2091 if (!partial)
2092 partial = chain + k-1;
2093 /*
2094 * If the branch acquired continuation since we've looked at it -
2095 * fine, it should all survive and (new) top doesn't belong to us.
2096 */
2097 if (!partial->key && *partial->p)
2098 /* Writer: end */
2099 goto no_top;
2100 for (p=partial; p>chain && all_zeroes((__le32*)p->bh->b_data,p->p); p--)
2101 ;
2102 /*
2103 * OK, we've found the last block that must survive. The rest of our
2104 * branch should be detached before unlocking. However, if that rest
2105 * of branch is all ours and does not grow immediately from the inode
2106 * it's easier to cheat and just decrement partial->p.
2107 */
2108 if (p == chain + k - 1 && p > chain) {
2109 p->p--;
2110 } else {
2111 *top = *p->p;
2112 /* Nope, don't do this in ext3. Must leave the tree intact */
2113#if 0
2114 *p->p = 0;
2115#endif
2116 }
2117 /* Writer: end */
2118
Andrew Mortond6859bf2006-03-26 01:38:03 -08002119 while(partial > p) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002120 brelse(partial->bh);
2121 partial--;
2122 }
2123no_top:
2124 return partial;
2125}
2126
2127/*
2128 * Zero a number of block pointers in either an inode or an indirect block.
2129 * If we restart the transaction we must again get write access to the
2130 * indirect block for further modification.
2131 *
2132 * We release `count' blocks on disk, but (last - first) may be greater
2133 * than `count' because there can be holes in there.
2134 */
Andrew Mortond6859bf2006-03-26 01:38:03 -08002135static void ext3_clear_blocks(handle_t *handle, struct inode *inode,
Mingming Cao43d23f92006-06-25 05:48:07 -07002136 struct buffer_head *bh, ext3_fsblk_t block_to_free,
Andrew Mortond6859bf2006-03-26 01:38:03 -08002137 unsigned long count, __le32 *first, __le32 *last)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002138{
2139 __le32 *p;
2140 if (try_to_extend_transaction(handle, inode)) {
2141 if (bh) {
2142 BUFFER_TRACE(bh, "call ext3_journal_dirty_metadata");
2143 ext3_journal_dirty_metadata(handle, bh);
2144 }
2145 ext3_mark_inode_dirty(handle, inode);
Jan Kara00171d32009-08-11 19:06:10 +02002146 truncate_restart_transaction(handle, inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002147 if (bh) {
2148 BUFFER_TRACE(bh, "retaking write access");
2149 ext3_journal_get_write_access(handle, bh);
2150 }
2151 }
2152
2153 /*
2154 * Any buffers which are on the journal will be in memory. We find
2155 * them on the hash table so journal_revoke() will run journal_forget()
2156 * on them. We've already detached each block from the file, so
2157 * bforget() in journal_forget() should be safe.
2158 *
2159 * AKPM: turn on bforget in journal_forget()!!!
2160 */
2161 for (p = first; p < last; p++) {
2162 u32 nr = le32_to_cpu(*p);
2163 if (nr) {
2164 struct buffer_head *bh;
2165
2166 *p = 0;
2167 bh = sb_find_get_block(inode->i_sb, nr);
2168 ext3_forget(handle, 0, inode, bh, nr);
2169 }
2170 }
2171
2172 ext3_free_blocks(handle, inode, block_to_free, count);
2173}
2174
2175/**
2176 * ext3_free_data - free a list of data blocks
2177 * @handle: handle for this transaction
2178 * @inode: inode we are dealing with
2179 * @this_bh: indirect buffer_head which contains *@first and *@last
2180 * @first: array of block numbers
2181 * @last: points immediately past the end of array
2182 *
2183 * We are freeing all blocks refered from that array (numbers are stored as
2184 * little-endian 32-bit) and updating @inode->i_blocks appropriately.
2185 *
2186 * We accumulate contiguous runs of blocks to free. Conveniently, if these
2187 * blocks are contiguous then releasing them at one time will only affect one
2188 * or two bitmap blocks (+ group descriptor(s) and superblock) and we won't
2189 * actually use a lot of journal space.
2190 *
2191 * @this_bh will be %NULL if @first and @last point into the inode's direct
2192 * block pointers.
2193 */
2194static void ext3_free_data(handle_t *handle, struct inode *inode,
2195 struct buffer_head *this_bh,
2196 __le32 *first, __le32 *last)
2197{
Mingming Cao43d23f92006-06-25 05:48:07 -07002198 ext3_fsblk_t block_to_free = 0; /* Starting block # of a run */
Mingming Caoae6ddcc2006-09-27 01:49:27 -07002199 unsigned long count = 0; /* Number of blocks in the run */
Linus Torvalds1da177e2005-04-16 15:20:36 -07002200 __le32 *block_to_free_p = NULL; /* Pointer into inode/ind
2201 corresponding to
2202 block_to_free */
Mingming Cao43d23f92006-06-25 05:48:07 -07002203 ext3_fsblk_t nr; /* Current block # */
Linus Torvalds1da177e2005-04-16 15:20:36 -07002204 __le32 *p; /* Pointer into inode/ind
2205 for current block */
2206 int err;
2207
2208 if (this_bh) { /* For indirect block */
2209 BUFFER_TRACE(this_bh, "get_write_access");
2210 err = ext3_journal_get_write_access(handle, this_bh);
2211 /* Important: if we can't update the indirect pointers
2212 * to the blocks, we can't free them. */
2213 if (err)
2214 return;
2215 }
2216
2217 for (p = first; p < last; p++) {
2218 nr = le32_to_cpu(*p);
2219 if (nr) {
2220 /* accumulate blocks to free if they're contiguous */
2221 if (count == 0) {
2222 block_to_free = nr;
2223 block_to_free_p = p;
2224 count = 1;
2225 } else if (nr == block_to_free + count) {
2226 count++;
2227 } else {
Mingming Caoae6ddcc2006-09-27 01:49:27 -07002228 ext3_clear_blocks(handle, inode, this_bh,
Linus Torvalds1da177e2005-04-16 15:20:36 -07002229 block_to_free,
2230 count, block_to_free_p, p);
2231 block_to_free = nr;
2232 block_to_free_p = p;
2233 count = 1;
2234 }
2235 }
2236 }
2237
2238 if (count > 0)
2239 ext3_clear_blocks(handle, inode, this_bh, block_to_free,
2240 count, block_to_free_p, p);
2241
2242 if (this_bh) {
2243 BUFFER_TRACE(this_bh, "call ext3_journal_dirty_metadata");
Duane Griffin3ccc3162008-07-25 01:46:26 -07002244
2245 /*
2246 * The buffer head should have an attached journal head at this
2247 * point. However, if the data is corrupted and an indirect
2248 * block pointed to itself, it would have been detached when
2249 * the block was cleared. Check for this instead of OOPSing.
2250 */
2251 if (bh2jh(this_bh))
2252 ext3_journal_dirty_metadata(handle, this_bh);
2253 else
2254 ext3_error(inode->i_sb, "ext3_free_data",
2255 "circular indirect block detected, "
2256 "inode=%lu, block=%llu",
2257 inode->i_ino,
2258 (unsigned long long)this_bh->b_blocknr);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002259 }
2260}
2261
2262/**
2263 * ext3_free_branches - free an array of branches
2264 * @handle: JBD handle for this transaction
2265 * @inode: inode we are dealing with
2266 * @parent_bh: the buffer_head which contains *@first and *@last
2267 * @first: array of block numbers
2268 * @last: pointer immediately past the end of array
2269 * @depth: depth of the branches to free
2270 *
2271 * We are freeing all blocks refered from these branches (numbers are
2272 * stored as little-endian 32-bit) and updating @inode->i_blocks
2273 * appropriately.
2274 */
2275static void ext3_free_branches(handle_t *handle, struct inode *inode,
2276 struct buffer_head *parent_bh,
2277 __le32 *first, __le32 *last, int depth)
2278{
Mingming Cao43d23f92006-06-25 05:48:07 -07002279 ext3_fsblk_t nr;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002280 __le32 *p;
2281
2282 if (is_handle_aborted(handle))
2283 return;
2284
2285 if (depth--) {
2286 struct buffer_head *bh;
2287 int addr_per_block = EXT3_ADDR_PER_BLOCK(inode->i_sb);
2288 p = last;
2289 while (--p >= first) {
2290 nr = le32_to_cpu(*p);
2291 if (!nr)
2292 continue; /* A hole */
2293
2294 /* Go read the buffer for the next level down */
2295 bh = sb_bread(inode->i_sb, nr);
2296
2297 /*
2298 * A read failure? Report error and clear slot
2299 * (should be rare).
2300 */
2301 if (!bh) {
2302 ext3_error(inode->i_sb, "ext3_free_branches",
Eric Sandeeneee194e2006-09-27 01:49:30 -07002303 "Read failure, inode=%lu, block="E3FSBLK,
Linus Torvalds1da177e2005-04-16 15:20:36 -07002304 inode->i_ino, nr);
2305 continue;
2306 }
2307
2308 /* This zaps the entire block. Bottom up. */
2309 BUFFER_TRACE(bh, "free child branches");
2310 ext3_free_branches(handle, inode, bh,
2311 (__le32*)bh->b_data,
2312 (__le32*)bh->b_data + addr_per_block,
2313 depth);
2314
2315 /*
Linus Torvalds1da177e2005-04-16 15:20:36 -07002316 * Everything below this this pointer has been
2317 * released. Now let this top-of-subtree go.
2318 *
2319 * We want the freeing of this indirect block to be
2320 * atomic in the journal with the updating of the
2321 * bitmap block which owns it. So make some room in
2322 * the journal.
2323 *
2324 * We zero the parent pointer *after* freeing its
2325 * pointee in the bitmaps, so if extend_transaction()
2326 * for some reason fails to put the bitmap changes and
2327 * the release into the same transaction, recovery
2328 * will merely complain about releasing a free block,
2329 * rather than leaking blocks.
2330 */
2331 if (is_handle_aborted(handle))
2332 return;
2333 if (try_to_extend_transaction(handle, inode)) {
2334 ext3_mark_inode_dirty(handle, inode);
Jan Kara00171d32009-08-11 19:06:10 +02002335 truncate_restart_transaction(handle, inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002336 }
2337
Jan Karaf25f6242010-07-12 21:04:31 +02002338 /*
2339 * We've probably journalled the indirect block several
2340 * times during the truncate. But it's no longer
2341 * needed and we now drop it from the transaction via
2342 * journal_revoke().
2343 *
2344 * That's easy if it's exclusively part of this
2345 * transaction. But if it's part of the committing
2346 * transaction then journal_forget() will simply
2347 * brelse() it. That means that if the underlying
2348 * block is reallocated in ext3_get_block(),
2349 * unmap_underlying_metadata() will find this block
2350 * and will try to get rid of it. damn, damn. Thus
2351 * we don't allow a block to be reallocated until
2352 * a transaction freeing it has fully committed.
2353 *
2354 * We also have to make sure journal replay after a
2355 * crash does not overwrite non-journaled data blocks
2356 * with old metadata when the block got reallocated for
2357 * data. Thus we have to store a revoke record for a
2358 * block in the same transaction in which we free the
2359 * block.
2360 */
2361 ext3_forget(handle, 1, inode, bh, bh->b_blocknr);
2362
Linus Torvalds1da177e2005-04-16 15:20:36 -07002363 ext3_free_blocks(handle, inode, nr, 1);
2364
2365 if (parent_bh) {
2366 /*
2367 * The block which we have just freed is
2368 * pointed to by an indirect block: journal it
2369 */
2370 BUFFER_TRACE(parent_bh, "get_write_access");
2371 if (!ext3_journal_get_write_access(handle,
2372 parent_bh)){
2373 *p = 0;
2374 BUFFER_TRACE(parent_bh,
2375 "call ext3_journal_dirty_metadata");
Mingming Caoae6ddcc2006-09-27 01:49:27 -07002376 ext3_journal_dirty_metadata(handle,
Linus Torvalds1da177e2005-04-16 15:20:36 -07002377 parent_bh);
2378 }
2379 }
2380 }
2381 } else {
2382 /* We have reached the bottom of the tree. */
2383 BUFFER_TRACE(parent_bh, "free data blocks");
2384 ext3_free_data(handle, inode, parent_bh, first, last);
2385 }
2386}
2387
Duane Griffinae76dd92008-07-25 01:46:23 -07002388int ext3_can_truncate(struct inode *inode)
2389{
2390 if (IS_APPEND(inode) || IS_IMMUTABLE(inode))
2391 return 0;
2392 if (S_ISREG(inode->i_mode))
2393 return 1;
2394 if (S_ISDIR(inode->i_mode))
2395 return 1;
2396 if (S_ISLNK(inode->i_mode))
2397 return !ext3_inode_is_fast_symlink(inode);
2398 return 0;
2399}
2400
Linus Torvalds1da177e2005-04-16 15:20:36 -07002401/*
2402 * ext3_truncate()
2403 *
2404 * We block out ext3_get_block() block instantiations across the entire
2405 * transaction, and VFS/VM ensures that ext3_truncate() cannot run
2406 * simultaneously on behalf of the same inode.
2407 *
2408 * As we work through the truncate and commmit bits of it to the journal there
2409 * is one core, guiding principle: the file's tree must always be consistent on
2410 * disk. We must be able to restart the truncate after a crash.
2411 *
2412 * The file's tree may be transiently inconsistent in memory (although it
2413 * probably isn't), but whenever we close off and commit a journal transaction,
2414 * the contents of (the filesystem + the journal) must be consistent and
2415 * restartable. It's pretty simple, really: bottom up, right to left (although
2416 * left-to-right works OK too).
2417 *
2418 * Note that at recovery time, journal replay occurs *before* the restart of
2419 * truncate against the orphan inode list.
2420 *
2421 * The committed inode has the new, desired i_size (which is the same as
2422 * i_disksize in this case). After a crash, ext3_orphan_cleanup() will see
2423 * that this inode's truncate did not complete and it will again call
2424 * ext3_truncate() to have another go. So there will be instantiated blocks
2425 * to the right of the truncation point in a crashed ext3 filesystem. But
2426 * that's fine - as long as they are linked from the inode, the post-crash
2427 * ext3_truncate() run will find them and release them.
2428 */
Andrew Mortond6859bf2006-03-26 01:38:03 -08002429void ext3_truncate(struct inode *inode)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002430{
2431 handle_t *handle;
2432 struct ext3_inode_info *ei = EXT3_I(inode);
2433 __le32 *i_data = ei->i_data;
2434 int addr_per_block = EXT3_ADDR_PER_BLOCK(inode->i_sb);
2435 struct address_space *mapping = inode->i_mapping;
2436 int offsets[4];
2437 Indirect chain[4];
2438 Indirect *partial;
2439 __le32 nr = 0;
2440 int n;
2441 long last_block;
2442 unsigned blocksize = inode->i_sb->s_blocksize;
2443 struct page *page;
2444
Duane Griffinae76dd92008-07-25 01:46:23 -07002445 if (!ext3_can_truncate(inode))
Jan Karaef436182009-06-17 16:26:24 -07002446 goto out_notrans;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002447
Theodore Ts'of7ab34e2009-04-03 01:34:35 -04002448 if (inode->i_size == 0 && ext3_should_writeback_data(inode))
Jan Kara9df93932010-01-06 21:58:48 +01002449 ext3_set_inode_state(inode, EXT3_STATE_FLUSH_ON_CLOSE);
Theodore Ts'of7ab34e2009-04-03 01:34:35 -04002450
Linus Torvalds1da177e2005-04-16 15:20:36 -07002451 /*
2452 * We have to lock the EOF page here, because lock_page() nests
2453 * outside journal_start().
2454 */
2455 if ((inode->i_size & (blocksize - 1)) == 0) {
2456 /* Block boundary? Nothing to do */
2457 page = NULL;
2458 } else {
2459 page = grab_cache_page(mapping,
2460 inode->i_size >> PAGE_CACHE_SHIFT);
2461 if (!page)
Jan Karaef436182009-06-17 16:26:24 -07002462 goto out_notrans;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002463 }
2464
2465 handle = start_transaction(inode);
2466 if (IS_ERR(handle)) {
2467 if (page) {
2468 clear_highpage(page);
2469 flush_dcache_page(page);
2470 unlock_page(page);
2471 page_cache_release(page);
2472 }
Jan Karaef436182009-06-17 16:26:24 -07002473 goto out_notrans;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002474 }
2475
2476 last_block = (inode->i_size + blocksize-1)
2477 >> EXT3_BLOCK_SIZE_BITS(inode->i_sb);
2478
2479 if (page)
2480 ext3_block_truncate_page(handle, page, mapping, inode->i_size);
2481
2482 n = ext3_block_to_path(inode, last_block, offsets, NULL);
2483 if (n == 0)
2484 goto out_stop; /* error */
2485
2486 /*
2487 * OK. This truncate is going to happen. We add the inode to the
2488 * orphan list, so that if this truncate spans multiple transactions,
2489 * and we crash, we will resume the truncate when the filesystem
2490 * recovers. It also marks the inode dirty, to catch the new size.
2491 *
2492 * Implication: the file must always be in a sane, consistent
2493 * truncatable state while each transaction commits.
2494 */
2495 if (ext3_orphan_add(handle, inode))
2496 goto out_stop;
2497
2498 /*
2499 * The orphan list entry will now protect us from any crash which
2500 * occurs before the truncate completes, so it is now safe to propagate
2501 * the new, shorter inode size (held for now in i_size) into the
2502 * on-disk inode. We do this via i_disksize, which is the value which
2503 * ext3 *really* writes onto the disk inode.
2504 */
2505 ei->i_disksize = inode->i_size;
2506
2507 /*
2508 * From here we block out all ext3_get_block() callers who want to
2509 * modify the block allocation tree.
2510 */
Arjan van de Ven97461512006-03-23 03:00:42 -08002511 mutex_lock(&ei->truncate_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002512
2513 if (n == 1) { /* direct blocks */
2514 ext3_free_data(handle, inode, NULL, i_data+offsets[0],
2515 i_data + EXT3_NDIR_BLOCKS);
2516 goto do_indirects;
2517 }
2518
2519 partial = ext3_find_shared(inode, n, offsets, chain, &nr);
2520 /* Kill the top of shared branch (not detached) */
2521 if (nr) {
2522 if (partial == chain) {
2523 /* Shared branch grows from the inode */
2524 ext3_free_branches(handle, inode, NULL,
2525 &nr, &nr+1, (chain+n-1) - partial);
2526 *partial->p = 0;
2527 /*
2528 * We mark the inode dirty prior to restart,
2529 * and prior to stop. No need for it here.
2530 */
2531 } else {
2532 /* Shared branch grows from an indirect block */
2533 BUFFER_TRACE(partial->bh, "get_write_access");
2534 ext3_free_branches(handle, inode, partial->bh,
2535 partial->p,
2536 partial->p+1, (chain+n-1) - partial);
2537 }
2538 }
2539 /* Clear the ends of indirect blocks on the shared branch */
2540 while (partial > chain) {
2541 ext3_free_branches(handle, inode, partial->bh, partial->p + 1,
2542 (__le32*)partial->bh->b_data+addr_per_block,
2543 (chain+n-1) - partial);
2544 BUFFER_TRACE(partial->bh, "call brelse");
2545 brelse (partial->bh);
2546 partial--;
2547 }
2548do_indirects:
2549 /* Kill the remaining (whole) subtrees */
2550 switch (offsets[0]) {
Andrew Mortond6859bf2006-03-26 01:38:03 -08002551 default:
2552 nr = i_data[EXT3_IND_BLOCK];
2553 if (nr) {
2554 ext3_free_branches(handle, inode, NULL, &nr, &nr+1, 1);
2555 i_data[EXT3_IND_BLOCK] = 0;
2556 }
2557 case EXT3_IND_BLOCK:
2558 nr = i_data[EXT3_DIND_BLOCK];
2559 if (nr) {
2560 ext3_free_branches(handle, inode, NULL, &nr, &nr+1, 2);
2561 i_data[EXT3_DIND_BLOCK] = 0;
2562 }
2563 case EXT3_DIND_BLOCK:
2564 nr = i_data[EXT3_TIND_BLOCK];
2565 if (nr) {
2566 ext3_free_branches(handle, inode, NULL, &nr, &nr+1, 3);
2567 i_data[EXT3_TIND_BLOCK] = 0;
2568 }
2569 case EXT3_TIND_BLOCK:
2570 ;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002571 }
2572
2573 ext3_discard_reservation(inode);
2574
Arjan van de Ven97461512006-03-23 03:00:42 -08002575 mutex_unlock(&ei->truncate_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002576 inode->i_mtime = inode->i_ctime = CURRENT_TIME_SEC;
2577 ext3_mark_inode_dirty(handle, inode);
2578
Andrew Mortond6859bf2006-03-26 01:38:03 -08002579 /*
2580 * In a multi-transaction truncate, we only make the final transaction
2581 * synchronous
2582 */
Linus Torvalds1da177e2005-04-16 15:20:36 -07002583 if (IS_SYNC(inode))
2584 handle->h_sync = 1;
2585out_stop:
2586 /*
2587 * If this was a simple ftruncate(), and the file will remain alive
2588 * then we need to clear up the orphan record which we created above.
2589 * However, if this was a real unlink then we were called by
Al Viroac14a952010-06-06 07:08:19 -04002590 * ext3_evict_inode(), and we allow that function to clean up the
Linus Torvalds1da177e2005-04-16 15:20:36 -07002591 * orphan info for us.
2592 */
2593 if (inode->i_nlink)
2594 ext3_orphan_del(handle, inode);
2595
2596 ext3_journal_stop(handle);
Jan Karaef436182009-06-17 16:26:24 -07002597 return;
2598out_notrans:
2599 /*
2600 * Delete the inode from orphan list so that it doesn't stay there
2601 * forever and trigger assertion on umount.
2602 */
2603 if (inode->i_nlink)
2604 ext3_orphan_del(NULL, inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002605}
2606
Mingming Cao43d23f92006-06-25 05:48:07 -07002607static ext3_fsblk_t ext3_get_inode_block(struct super_block *sb,
Linus Torvalds1da177e2005-04-16 15:20:36 -07002608 unsigned long ino, struct ext3_iloc *iloc)
2609{
Akinobu Mitae0e369a2008-04-28 02:16:08 -07002610 unsigned long block_group;
Mingming Cao43d23f92006-06-25 05:48:07 -07002611 unsigned long offset;
2612 ext3_fsblk_t block;
Akinobu Mitae0e369a2008-04-28 02:16:08 -07002613 struct ext3_group_desc *gdp;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002614
Neil Brown2ccb48e2006-07-30 03:03:01 -07002615 if (!ext3_valid_inum(sb, ino)) {
2616 /*
2617 * This error is already checked for in namei.c unless we are
2618 * looking at an NFS filehandle, in which case no error
2619 * report is needed
2620 */
Linus Torvalds1da177e2005-04-16 15:20:36 -07002621 return 0;
2622 }
Neil Brown2ccb48e2006-07-30 03:03:01 -07002623
Linus Torvalds1da177e2005-04-16 15:20:36 -07002624 block_group = (ino - 1) / EXT3_INODES_PER_GROUP(sb);
Akinobu Mitae0e369a2008-04-28 02:16:08 -07002625 gdp = ext3_get_group_desc(sb, block_group, NULL);
2626 if (!gdp)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002627 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002628 /*
2629 * Figure out the offset within the block group inode table
2630 */
2631 offset = ((ino - 1) % EXT3_INODES_PER_GROUP(sb)) *
2632 EXT3_INODE_SIZE(sb);
Akinobu Mitae0e369a2008-04-28 02:16:08 -07002633 block = le32_to_cpu(gdp->bg_inode_table) +
Linus Torvalds1da177e2005-04-16 15:20:36 -07002634 (offset >> EXT3_BLOCK_SIZE_BITS(sb));
2635
2636 iloc->block_group = block_group;
2637 iloc->offset = offset & (EXT3_BLOCK_SIZE(sb) - 1);
2638 return block;
2639}
2640
2641/*
2642 * ext3_get_inode_loc returns with an extra refcount against the inode's
2643 * underlying buffer_head on success. If 'in_mem' is true, we have all
2644 * data in memory that is needed to recreate the on-disk version of this
2645 * inode.
2646 */
2647static int __ext3_get_inode_loc(struct inode *inode,
2648 struct ext3_iloc *iloc, int in_mem)
2649{
Mingming Cao43d23f92006-06-25 05:48:07 -07002650 ext3_fsblk_t block;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002651 struct buffer_head *bh;
2652
2653 block = ext3_get_inode_block(inode->i_sb, inode->i_ino, iloc);
2654 if (!block)
2655 return -EIO;
2656
2657 bh = sb_getblk(inode->i_sb, block);
2658 if (!bh) {
2659 ext3_error (inode->i_sb, "ext3_get_inode_loc",
2660 "unable to read inode block - "
Mingming Cao43d23f92006-06-25 05:48:07 -07002661 "inode=%lu, block="E3FSBLK,
2662 inode->i_ino, block);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002663 return -EIO;
2664 }
2665 if (!buffer_uptodate(bh)) {
2666 lock_buffer(bh);
Hidehiro Kawai95450f52008-07-25 01:46:24 -07002667
2668 /*
2669 * If the buffer has the write error flag, we have failed
2670 * to write out another inode in the same block. In this
2671 * case, we don't have to read the block because we may
2672 * read the old inode data successfully.
2673 */
2674 if (buffer_write_io_error(bh) && !buffer_uptodate(bh))
2675 set_buffer_uptodate(bh);
2676
Linus Torvalds1da177e2005-04-16 15:20:36 -07002677 if (buffer_uptodate(bh)) {
2678 /* someone brought it uptodate while we waited */
2679 unlock_buffer(bh);
2680 goto has_buffer;
2681 }
2682
2683 /*
2684 * If we have all information of the inode in memory and this
2685 * is the only valid inode in the block, we need not read the
2686 * block.
2687 */
2688 if (in_mem) {
2689 struct buffer_head *bitmap_bh;
2690 struct ext3_group_desc *desc;
2691 int inodes_per_buffer;
2692 int inode_offset, i;
2693 int block_group;
2694 int start;
2695
2696 block_group = (inode->i_ino - 1) /
2697 EXT3_INODES_PER_GROUP(inode->i_sb);
2698 inodes_per_buffer = bh->b_size /
2699 EXT3_INODE_SIZE(inode->i_sb);
2700 inode_offset = ((inode->i_ino - 1) %
2701 EXT3_INODES_PER_GROUP(inode->i_sb));
2702 start = inode_offset & ~(inodes_per_buffer - 1);
2703
2704 /* Is the inode bitmap in cache? */
2705 desc = ext3_get_group_desc(inode->i_sb,
2706 block_group, NULL);
2707 if (!desc)
2708 goto make_io;
2709
2710 bitmap_bh = sb_getblk(inode->i_sb,
2711 le32_to_cpu(desc->bg_inode_bitmap));
2712 if (!bitmap_bh)
2713 goto make_io;
2714
2715 /*
2716 * If the inode bitmap isn't in cache then the
2717 * optimisation may end up performing two reads instead
2718 * of one, so skip it.
2719 */
2720 if (!buffer_uptodate(bitmap_bh)) {
2721 brelse(bitmap_bh);
2722 goto make_io;
2723 }
2724 for (i = start; i < start + inodes_per_buffer; i++) {
2725 if (i == inode_offset)
2726 continue;
2727 if (ext3_test_bit(i, bitmap_bh->b_data))
2728 break;
2729 }
2730 brelse(bitmap_bh);
2731 if (i == start + inodes_per_buffer) {
2732 /* all other inodes are free, so skip I/O */
2733 memset(bh->b_data, 0, bh->b_size);
2734 set_buffer_uptodate(bh);
2735 unlock_buffer(bh);
2736 goto has_buffer;
2737 }
2738 }
2739
2740make_io:
2741 /*
2742 * There are other valid inodes in the buffer, this inode
2743 * has in-inode xattrs, or we don't have this inode in memory.
2744 * Read the block from disk.
2745 */
2746 get_bh(bh);
2747 bh->b_end_io = end_buffer_read_sync;
Jens Axboecaa38fb2006-07-23 01:41:26 +02002748 submit_bh(READ_META, bh);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002749 wait_on_buffer(bh);
2750 if (!buffer_uptodate(bh)) {
2751 ext3_error(inode->i_sb, "ext3_get_inode_loc",
2752 "unable to read inode block - "
Mingming Cao43d23f92006-06-25 05:48:07 -07002753 "inode=%lu, block="E3FSBLK,
Linus Torvalds1da177e2005-04-16 15:20:36 -07002754 inode->i_ino, block);
2755 brelse(bh);
2756 return -EIO;
2757 }
2758 }
2759has_buffer:
2760 iloc->bh = bh;
2761 return 0;
2762}
2763
2764int ext3_get_inode_loc(struct inode *inode, struct ext3_iloc *iloc)
2765{
2766 /* We have all inode data except xattrs in memory here. */
2767 return __ext3_get_inode_loc(inode, iloc,
Jan Kara9df93932010-01-06 21:58:48 +01002768 !ext3_test_inode_state(inode, EXT3_STATE_XATTR));
Linus Torvalds1da177e2005-04-16 15:20:36 -07002769}
2770
2771void ext3_set_inode_flags(struct inode *inode)
2772{
2773 unsigned int flags = EXT3_I(inode)->i_flags;
2774
2775 inode->i_flags &= ~(S_SYNC|S_APPEND|S_IMMUTABLE|S_NOATIME|S_DIRSYNC);
2776 if (flags & EXT3_SYNC_FL)
2777 inode->i_flags |= S_SYNC;
2778 if (flags & EXT3_APPEND_FL)
2779 inode->i_flags |= S_APPEND;
2780 if (flags & EXT3_IMMUTABLE_FL)
2781 inode->i_flags |= S_IMMUTABLE;
2782 if (flags & EXT3_NOATIME_FL)
2783 inode->i_flags |= S_NOATIME;
2784 if (flags & EXT3_DIRSYNC_FL)
2785 inode->i_flags |= S_DIRSYNC;
2786}
2787
Jan Kara28be5ab2007-05-08 00:30:33 -07002788/* Propagate flags from i_flags to EXT3_I(inode)->i_flags */
2789void ext3_get_inode_flags(struct ext3_inode_info *ei)
2790{
2791 unsigned int flags = ei->vfs_inode.i_flags;
2792
2793 ei->i_flags &= ~(EXT3_SYNC_FL|EXT3_APPEND_FL|
2794 EXT3_IMMUTABLE_FL|EXT3_NOATIME_FL|EXT3_DIRSYNC_FL);
2795 if (flags & S_SYNC)
2796 ei->i_flags |= EXT3_SYNC_FL;
2797 if (flags & S_APPEND)
2798 ei->i_flags |= EXT3_APPEND_FL;
2799 if (flags & S_IMMUTABLE)
2800 ei->i_flags |= EXT3_IMMUTABLE_FL;
2801 if (flags & S_NOATIME)
2802 ei->i_flags |= EXT3_NOATIME_FL;
2803 if (flags & S_DIRSYNC)
2804 ei->i_flags |= EXT3_DIRSYNC_FL;
2805}
2806
David Howells473043d2008-02-07 00:15:36 -08002807struct inode *ext3_iget(struct super_block *sb, unsigned long ino)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002808{
2809 struct ext3_iloc iloc;
2810 struct ext3_inode *raw_inode;
David Howells473043d2008-02-07 00:15:36 -08002811 struct ext3_inode_info *ei;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002812 struct buffer_head *bh;
David Howells473043d2008-02-07 00:15:36 -08002813 struct inode *inode;
Jan Karafe8bc912009-10-16 19:26:15 +02002814 journal_t *journal = EXT3_SB(sb)->s_journal;
2815 transaction_t *transaction;
David Howells473043d2008-02-07 00:15:36 -08002816 long ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002817 int block;
2818
David Howells473043d2008-02-07 00:15:36 -08002819 inode = iget_locked(sb, ino);
2820 if (!inode)
2821 return ERR_PTR(-ENOMEM);
2822 if (!(inode->i_state & I_NEW))
2823 return inode;
2824
2825 ei = EXT3_I(inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002826 ei->i_block_alloc_info = NULL;
2827
David Howells473043d2008-02-07 00:15:36 -08002828 ret = __ext3_get_inode_loc(inode, &iloc, 0);
2829 if (ret < 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002830 goto bad_inode;
2831 bh = iloc.bh;
2832 raw_inode = ext3_raw_inode(&iloc);
2833 inode->i_mode = le16_to_cpu(raw_inode->i_mode);
2834 inode->i_uid = (uid_t)le16_to_cpu(raw_inode->i_uid_low);
2835 inode->i_gid = (gid_t)le16_to_cpu(raw_inode->i_gid_low);
2836 if(!(test_opt (inode->i_sb, NO_UID32))) {
2837 inode->i_uid |= le16_to_cpu(raw_inode->i_uid_high) << 16;
2838 inode->i_gid |= le16_to_cpu(raw_inode->i_gid_high) << 16;
2839 }
2840 inode->i_nlink = le16_to_cpu(raw_inode->i_links_count);
2841 inode->i_size = le32_to_cpu(raw_inode->i_size);
Markus Rechberger4d7bf112007-05-08 00:23:39 -07002842 inode->i_atime.tv_sec = (signed)le32_to_cpu(raw_inode->i_atime);
2843 inode->i_ctime.tv_sec = (signed)le32_to_cpu(raw_inode->i_ctime);
2844 inode->i_mtime.tv_sec = (signed)le32_to_cpu(raw_inode->i_mtime);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002845 inode->i_atime.tv_nsec = inode->i_ctime.tv_nsec = inode->i_mtime.tv_nsec = 0;
2846
Linus Torvaldsde329822010-03-29 14:30:19 -07002847 ei->i_state_flags = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002848 ei->i_dir_start_lookup = 0;
2849 ei->i_dtime = le32_to_cpu(raw_inode->i_dtime);
2850 /* We now have enough fields to check if the inode was active or not.
2851 * This is needed because nfsd might try to access dead inodes
2852 * the test is that same one that e2fsck uses
2853 * NeilBrown 1999oct15
2854 */
2855 if (inode->i_nlink == 0) {
2856 if (inode->i_mode == 0 ||
2857 !(EXT3_SB(inode->i_sb)->s_mount_state & EXT3_ORPHAN_FS)) {
2858 /* this inode is deleted */
2859 brelse (bh);
David Howells473043d2008-02-07 00:15:36 -08002860 ret = -ESTALE;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002861 goto bad_inode;
2862 }
2863 /* The only unlinked inodes we let through here have
2864 * valid i_mode and are being read by the orphan
2865 * recovery code: that's fine, we're about to complete
2866 * the process of deleting those. */
2867 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07002868 inode->i_blocks = le32_to_cpu(raw_inode->i_blocks);
2869 ei->i_flags = le32_to_cpu(raw_inode->i_flags);
2870#ifdef EXT3_FRAGMENTS
2871 ei->i_faddr = le32_to_cpu(raw_inode->i_faddr);
2872 ei->i_frag_no = raw_inode->i_frag;
2873 ei->i_frag_size = raw_inode->i_fsize;
2874#endif
2875 ei->i_file_acl = le32_to_cpu(raw_inode->i_file_acl);
2876 if (!S_ISREG(inode->i_mode)) {
2877 ei->i_dir_acl = le32_to_cpu(raw_inode->i_dir_acl);
2878 } else {
2879 inode->i_size |=
2880 ((__u64)le32_to_cpu(raw_inode->i_size_high)) << 32;
2881 }
2882 ei->i_disksize = inode->i_size;
2883 inode->i_generation = le32_to_cpu(raw_inode->i_generation);
2884 ei->i_block_group = iloc.block_group;
2885 /*
2886 * NOTE! The in-memory inode i_data array is in little-endian order
2887 * even on big-endian machines: we do NOT byteswap the block numbers!
2888 */
2889 for (block = 0; block < EXT3_N_BLOCKS; block++)
2890 ei->i_data[block] = raw_inode->i_block[block];
2891 INIT_LIST_HEAD(&ei->i_orphan);
2892
Jan Karafe8bc912009-10-16 19:26:15 +02002893 /*
2894 * Set transaction id's of transactions that have to be committed
2895 * to finish f[data]sync. We set them to currently running transaction
2896 * as we cannot be sure that the inode or some of its metadata isn't
2897 * part of the transaction - the inode could have been reclaimed and
2898 * now it is reread from disk.
2899 */
2900 if (journal) {
2901 tid_t tid;
2902
2903 spin_lock(&journal->j_state_lock);
2904 if (journal->j_running_transaction)
2905 transaction = journal->j_running_transaction;
2906 else
2907 transaction = journal->j_committing_transaction;
2908 if (transaction)
2909 tid = transaction->t_tid;
2910 else
2911 tid = journal->j_commit_sequence;
2912 spin_unlock(&journal->j_state_lock);
2913 atomic_set(&ei->i_sync_tid, tid);
2914 atomic_set(&ei->i_datasync_tid, tid);
2915 }
2916
Linus Torvalds1da177e2005-04-16 15:20:36 -07002917 if (inode->i_ino >= EXT3_FIRST_INO(inode->i_sb) + 1 &&
2918 EXT3_INODE_SIZE(inode->i_sb) > EXT3_GOOD_OLD_INODE_SIZE) {
2919 /*
2920 * When mke2fs creates big inodes it does not zero out
2921 * the unused bytes above EXT3_GOOD_OLD_INODE_SIZE,
2922 * so ignore those first few inodes.
2923 */
2924 ei->i_extra_isize = le16_to_cpu(raw_inode->i_extra_isize);
2925 if (EXT3_GOOD_OLD_INODE_SIZE + ei->i_extra_isize >
Kirill Korotaeve4a10a32007-06-23 17:16:48 -07002926 EXT3_INODE_SIZE(inode->i_sb)) {
2927 brelse (bh);
David Howells473043d2008-02-07 00:15:36 -08002928 ret = -EIO;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002929 goto bad_inode;
Kirill Korotaeve4a10a32007-06-23 17:16:48 -07002930 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07002931 if (ei->i_extra_isize == 0) {
2932 /* The extra space is currently unused. Use it. */
2933 ei->i_extra_isize = sizeof(struct ext3_inode) -
2934 EXT3_GOOD_OLD_INODE_SIZE;
2935 } else {
2936 __le32 *magic = (void *)raw_inode +
2937 EXT3_GOOD_OLD_INODE_SIZE +
2938 ei->i_extra_isize;
2939 if (*magic == cpu_to_le32(EXT3_XATTR_MAGIC))
Jan Kara9df93932010-01-06 21:58:48 +01002940 ext3_set_inode_state(inode, EXT3_STATE_XATTR);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002941 }
2942 } else
2943 ei->i_extra_isize = 0;
2944
2945 if (S_ISREG(inode->i_mode)) {
2946 inode->i_op = &ext3_file_inode_operations;
2947 inode->i_fop = &ext3_file_operations;
2948 ext3_set_aops(inode);
2949 } else if (S_ISDIR(inode->i_mode)) {
2950 inode->i_op = &ext3_dir_inode_operations;
2951 inode->i_fop = &ext3_dir_operations;
2952 } else if (S_ISLNK(inode->i_mode)) {
Duane Griffinb5ed3112008-12-19 20:47:14 +00002953 if (ext3_inode_is_fast_symlink(inode)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002954 inode->i_op = &ext3_fast_symlink_inode_operations;
Duane Griffinb5ed3112008-12-19 20:47:14 +00002955 nd_terminate_link(ei->i_data, inode->i_size,
2956 sizeof(ei->i_data) - 1);
2957 } else {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002958 inode->i_op = &ext3_symlink_inode_operations;
2959 ext3_set_aops(inode);
2960 }
2961 } else {
2962 inode->i_op = &ext3_special_inode_operations;
2963 if (raw_inode->i_block[0])
2964 init_special_inode(inode, inode->i_mode,
2965 old_decode_dev(le32_to_cpu(raw_inode->i_block[0])));
Mingming Caoae6ddcc2006-09-27 01:49:27 -07002966 else
Linus Torvalds1da177e2005-04-16 15:20:36 -07002967 init_special_inode(inode, inode->i_mode,
2968 new_decode_dev(le32_to_cpu(raw_inode->i_block[1])));
2969 }
2970 brelse (iloc.bh);
2971 ext3_set_inode_flags(inode);
David Howells473043d2008-02-07 00:15:36 -08002972 unlock_new_inode(inode);
2973 return inode;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002974
2975bad_inode:
David Howells473043d2008-02-07 00:15:36 -08002976 iget_failed(inode);
2977 return ERR_PTR(ret);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002978}
2979
2980/*
2981 * Post the struct inode info into an on-disk inode location in the
2982 * buffer-cache. This gobbles the caller's reference to the
2983 * buffer_head in the inode location struct.
2984 *
2985 * The caller must have write access to iloc->bh.
2986 */
Mingming Caoae6ddcc2006-09-27 01:49:27 -07002987static int ext3_do_update_inode(handle_t *handle,
2988 struct inode *inode,
Linus Torvalds1da177e2005-04-16 15:20:36 -07002989 struct ext3_iloc *iloc)
2990{
2991 struct ext3_inode *raw_inode = ext3_raw_inode(iloc);
2992 struct ext3_inode_info *ei = EXT3_I(inode);
2993 struct buffer_head *bh = iloc->bh;
2994 int err = 0, rc, block;
2995
Chris Mason4f003fd2009-09-08 00:22:14 +02002996again:
2997 /* we can't allow multiple procs in here at once, its a bit racey */
2998 lock_buffer(bh);
2999
Linus Torvalds1da177e2005-04-16 15:20:36 -07003000 /* For fields not not tracking in the in-memory inode,
3001 * initialise them to zero for new inodes. */
Jan Kara9df93932010-01-06 21:58:48 +01003002 if (ext3_test_inode_state(inode, EXT3_STATE_NEW))
Linus Torvalds1da177e2005-04-16 15:20:36 -07003003 memset(raw_inode, 0, EXT3_SB(inode->i_sb)->s_inode_size);
3004
Jan Kara28be5ab2007-05-08 00:30:33 -07003005 ext3_get_inode_flags(ei);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003006 raw_inode->i_mode = cpu_to_le16(inode->i_mode);
3007 if(!(test_opt(inode->i_sb, NO_UID32))) {
3008 raw_inode->i_uid_low = cpu_to_le16(low_16_bits(inode->i_uid));
3009 raw_inode->i_gid_low = cpu_to_le16(low_16_bits(inode->i_gid));
3010/*
3011 * Fix up interoperability with old kernels. Otherwise, old inodes get
3012 * re-used with the upper 16 bits of the uid/gid intact
3013 */
3014 if(!ei->i_dtime) {
3015 raw_inode->i_uid_high =
3016 cpu_to_le16(high_16_bits(inode->i_uid));
3017 raw_inode->i_gid_high =
3018 cpu_to_le16(high_16_bits(inode->i_gid));
3019 } else {
3020 raw_inode->i_uid_high = 0;
3021 raw_inode->i_gid_high = 0;
3022 }
3023 } else {
3024 raw_inode->i_uid_low =
3025 cpu_to_le16(fs_high2lowuid(inode->i_uid));
3026 raw_inode->i_gid_low =
3027 cpu_to_le16(fs_high2lowgid(inode->i_gid));
3028 raw_inode->i_uid_high = 0;
3029 raw_inode->i_gid_high = 0;
3030 }
3031 raw_inode->i_links_count = cpu_to_le16(inode->i_nlink);
3032 raw_inode->i_size = cpu_to_le32(ei->i_disksize);
3033 raw_inode->i_atime = cpu_to_le32(inode->i_atime.tv_sec);
3034 raw_inode->i_ctime = cpu_to_le32(inode->i_ctime.tv_sec);
3035 raw_inode->i_mtime = cpu_to_le32(inode->i_mtime.tv_sec);
3036 raw_inode->i_blocks = cpu_to_le32(inode->i_blocks);
3037 raw_inode->i_dtime = cpu_to_le32(ei->i_dtime);
3038 raw_inode->i_flags = cpu_to_le32(ei->i_flags);
3039#ifdef EXT3_FRAGMENTS
3040 raw_inode->i_faddr = cpu_to_le32(ei->i_faddr);
3041 raw_inode->i_frag = ei->i_frag_no;
3042 raw_inode->i_fsize = ei->i_frag_size;
3043#endif
3044 raw_inode->i_file_acl = cpu_to_le32(ei->i_file_acl);
3045 if (!S_ISREG(inode->i_mode)) {
3046 raw_inode->i_dir_acl = cpu_to_le32(ei->i_dir_acl);
3047 } else {
3048 raw_inode->i_size_high =
3049 cpu_to_le32(ei->i_disksize >> 32);
3050 if (ei->i_disksize > 0x7fffffffULL) {
3051 struct super_block *sb = inode->i_sb;
3052 if (!EXT3_HAS_RO_COMPAT_FEATURE(sb,
3053 EXT3_FEATURE_RO_COMPAT_LARGE_FILE) ||
3054 EXT3_SB(sb)->s_es->s_rev_level ==
3055 cpu_to_le32(EXT3_GOOD_OLD_REV)) {
3056 /* If this is the first large file
3057 * created, add a flag to the superblock.
3058 */
Chris Mason4f003fd2009-09-08 00:22:14 +02003059 unlock_buffer(bh);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003060 err = ext3_journal_get_write_access(handle,
3061 EXT3_SB(sb)->s_sbh);
3062 if (err)
3063 goto out_brelse;
Chris Mason4f003fd2009-09-08 00:22:14 +02003064
Linus Torvalds1da177e2005-04-16 15:20:36 -07003065 ext3_update_dynamic_rev(sb);
3066 EXT3_SET_RO_COMPAT_FEATURE(sb,
3067 EXT3_FEATURE_RO_COMPAT_LARGE_FILE);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003068 handle->h_sync = 1;
3069 err = ext3_journal_dirty_metadata(handle,
3070 EXT3_SB(sb)->s_sbh);
Chris Mason4f003fd2009-09-08 00:22:14 +02003071 /* get our lock and start over */
3072 goto again;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003073 }
3074 }
3075 }
3076 raw_inode->i_generation = cpu_to_le32(inode->i_generation);
3077 if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) {
3078 if (old_valid_dev(inode->i_rdev)) {
3079 raw_inode->i_block[0] =
3080 cpu_to_le32(old_encode_dev(inode->i_rdev));
3081 raw_inode->i_block[1] = 0;
3082 } else {
3083 raw_inode->i_block[0] = 0;
3084 raw_inode->i_block[1] =
3085 cpu_to_le32(new_encode_dev(inode->i_rdev));
3086 raw_inode->i_block[2] = 0;
3087 }
3088 } else for (block = 0; block < EXT3_N_BLOCKS; block++)
3089 raw_inode->i_block[block] = ei->i_data[block];
3090
Andreas Gruenbacherff87b372005-07-07 17:57:00 -07003091 if (ei->i_extra_isize)
Linus Torvalds1da177e2005-04-16 15:20:36 -07003092 raw_inode->i_extra_isize = cpu_to_le16(ei->i_extra_isize);
3093
3094 BUFFER_TRACE(bh, "call ext3_journal_dirty_metadata");
Chris Mason4f003fd2009-09-08 00:22:14 +02003095 unlock_buffer(bh);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003096 rc = ext3_journal_dirty_metadata(handle, bh);
3097 if (!err)
3098 err = rc;
Jan Kara9df93932010-01-06 21:58:48 +01003099 ext3_clear_inode_state(inode, EXT3_STATE_NEW);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003100
Jan Karafe8bc912009-10-16 19:26:15 +02003101 atomic_set(&ei->i_sync_tid, handle->h_transaction->t_tid);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003102out_brelse:
3103 brelse (bh);
3104 ext3_std_error(inode->i_sb, err);
3105 return err;
3106}
3107
3108/*
3109 * ext3_write_inode()
3110 *
3111 * We are called from a few places:
3112 *
3113 * - Within generic_file_write() for O_SYNC files.
3114 * Here, there will be no transaction running. We wait for any running
3115 * trasnaction to commit.
3116 *
3117 * - Within sys_sync(), kupdate and such.
3118 * We wait on commit, if tol to.
3119 *
3120 * - Within prune_icache() (PF_MEMALLOC == true)
3121 * Here we simply return. We can't afford to block kswapd on the
3122 * journal commit.
3123 *
3124 * In all cases it is actually safe for us to return without doing anything,
3125 * because the inode has been copied into a raw inode buffer in
3126 * ext3_mark_inode_dirty(). This is a correctness thing for O_SYNC and for
3127 * knfsd.
3128 *
3129 * Note that we are absolutely dependent upon all inode dirtiers doing the
3130 * right thing: they *must* call mark_inode_dirty() after dirtying info in
3131 * which we are interested.
3132 *
3133 * It would be a bug for them to not do this. The code:
3134 *
3135 * mark_inode_dirty(inode)
3136 * stuff();
3137 * inode->i_size = expr;
3138 *
3139 * is in error because a kswapd-driven write_inode() could occur while
3140 * `stuff()' is running, and the new i_size will be lost. Plus the inode
3141 * will no longer be on the superblock's dirty inode list.
3142 */
Christoph Hellwiga9185b42010-03-05 09:21:37 +01003143int ext3_write_inode(struct inode *inode, struct writeback_control *wbc)
Linus Torvalds1da177e2005-04-16 15:20:36 -07003144{
3145 if (current->flags & PF_MEMALLOC)
3146 return 0;
3147
3148 if (ext3_journal_current_handle()) {
Jose R. Santos9ad163a2007-10-18 23:39:23 -07003149 jbd_debug(1, "called recursively, non-PF_MEMALLOC!\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -07003150 dump_stack();
3151 return -EIO;
3152 }
3153
Christoph Hellwiga9185b42010-03-05 09:21:37 +01003154 if (wbc->sync_mode != WB_SYNC_ALL)
Linus Torvalds1da177e2005-04-16 15:20:36 -07003155 return 0;
3156
3157 return ext3_force_commit(inode->i_sb);
3158}
3159
3160/*
3161 * ext3_setattr()
3162 *
3163 * Called from notify_change.
3164 *
3165 * We want to trap VFS attempts to truncate the file as soon as
3166 * possible. In particular, we want to make sure that when the VFS
3167 * shrinks i_size, we put the inode on the orphan list and modify
3168 * i_disksize immediately, so that during the subsequent flushing of
3169 * dirty pages and freeing of disk blocks, we can guarantee that any
3170 * commit will leave the blocks being flushed in an unused state on
3171 * disk. (On recovery, the inode will get truncated and the blocks will
3172 * be freed, so we have a strong guarantee that no future commit will
Mingming Caoae6ddcc2006-09-27 01:49:27 -07003173 * leave these blocks visible to the user.)
Linus Torvalds1da177e2005-04-16 15:20:36 -07003174 *
3175 * Called with inode->sem down.
3176 */
3177int ext3_setattr(struct dentry *dentry, struct iattr *attr)
3178{
3179 struct inode *inode = dentry->d_inode;
3180 int error, rc = 0;
3181 const unsigned int ia_valid = attr->ia_valid;
3182
3183 error = inode_change_ok(inode, attr);
3184 if (error)
3185 return error;
3186
Dmitry Monakhov12755622010-04-08 22:04:20 +04003187 if (is_quota_modification(inode, attr))
Christoph Hellwig871a2932010-03-03 09:05:07 -05003188 dquot_initialize(inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003189 if ((ia_valid & ATTR_UID && attr->ia_uid != inode->i_uid) ||
3190 (ia_valid & ATTR_GID && attr->ia_gid != inode->i_gid)) {
3191 handle_t *handle;
3192
3193 /* (user+group)*(old+new) structure, inode write (sb,
3194 * inode block, ? - but truncate inode update has it) */
Dmitry Monakhovc4590012009-12-09 03:05:30 +03003195 handle = ext3_journal_start(inode, EXT3_MAXQUOTAS_INIT_BLOCKS(inode->i_sb)+
3196 EXT3_MAXQUOTAS_DEL_BLOCKS(inode->i_sb)+3);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003197 if (IS_ERR(handle)) {
3198 error = PTR_ERR(handle);
3199 goto err_out;
3200 }
Christoph Hellwigb43fa822010-03-03 09:05:03 -05003201 error = dquot_transfer(inode, attr);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003202 if (error) {
3203 ext3_journal_stop(handle);
3204 return error;
3205 }
3206 /* Update corresponding info in inode so that everything is in
3207 * one transaction */
3208 if (attr->ia_valid & ATTR_UID)
3209 inode->i_uid = attr->ia_uid;
3210 if (attr->ia_valid & ATTR_GID)
3211 inode->i_gid = attr->ia_gid;
3212 error = ext3_mark_inode_dirty(handle, inode);
3213 ext3_journal_stop(handle);
3214 }
3215
3216 if (S_ISREG(inode->i_mode) &&
3217 attr->ia_valid & ATTR_SIZE && attr->ia_size < inode->i_size) {
3218 handle_t *handle;
3219
3220 handle = ext3_journal_start(inode, 3);
3221 if (IS_ERR(handle)) {
3222 error = PTR_ERR(handle);
3223 goto err_out;
3224 }
3225
3226 error = ext3_orphan_add(handle, inode);
3227 EXT3_I(inode)->i_disksize = attr->ia_size;
3228 rc = ext3_mark_inode_dirty(handle, inode);
3229 if (!error)
3230 error = rc;
3231 ext3_journal_stop(handle);
3232 }
3233
Christoph Hellwig10257742010-06-04 11:30:02 +02003234 if ((attr->ia_valid & ATTR_SIZE) &&
3235 attr->ia_size != i_size_read(inode)) {
3236 rc = vmtruncate(inode, attr->ia_size);
3237 if (rc)
3238 goto err_out;
3239 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07003240
Christoph Hellwig10257742010-06-04 11:30:02 +02003241 setattr_copy(inode, attr);
3242 mark_inode_dirty(inode);
3243
3244 if (ia_valid & ATTR_MODE)
Linus Torvalds1da177e2005-04-16 15:20:36 -07003245 rc = ext3_acl_chmod(inode);
3246
3247err_out:
3248 ext3_std_error(inode->i_sb, error);
3249 if (!error)
3250 error = rc;
3251 return error;
3252}
3253
3254
3255/*
Andrew Mortond6859bf2006-03-26 01:38:03 -08003256 * How many blocks doth make a writepage()?
Linus Torvalds1da177e2005-04-16 15:20:36 -07003257 *
3258 * With N blocks per page, it may be:
3259 * N data blocks
3260 * 2 indirect block
3261 * 2 dindirect
3262 * 1 tindirect
3263 * N+5 bitmap blocks (from the above)
3264 * N+5 group descriptor summary blocks
3265 * 1 inode block
3266 * 1 superblock.
3267 * 2 * EXT3_SINGLEDATA_TRANS_BLOCKS for the quote files
3268 *
3269 * 3 * (N + 5) + 2 + 2 * EXT3_SINGLEDATA_TRANS_BLOCKS
3270 *
3271 * With ordered or writeback data it's the same, less the N data blocks.
3272 *
3273 * If the inode's direct blocks can hold an integral number of pages then a
3274 * page cannot straddle two indirect blocks, and we can only touch one indirect
3275 * and dindirect block, and the "5" above becomes "3".
3276 *
3277 * This still overestimates under most circumstances. If we were to pass the
3278 * start and end offsets in here as well we could do block_to_path() on each
3279 * block and work out the exact number of indirects which are touched. Pah.
3280 */
3281
3282static int ext3_writepage_trans_blocks(struct inode *inode)
3283{
3284 int bpp = ext3_journal_blocks_per_page(inode);
3285 int indirects = (EXT3_NDIR_BLOCKS % bpp) ? 5 : 3;
3286 int ret;
3287
3288 if (ext3_should_journal_data(inode))
3289 ret = 3 * (bpp + indirects) + 2;
3290 else
3291 ret = 2 * (bpp + indirects) + 2;
3292
3293#ifdef CONFIG_QUOTA
Christoph Hellwig871a2932010-03-03 09:05:07 -05003294 /* We know that structure was already allocated during dquot_initialize so
Linus Torvalds1da177e2005-04-16 15:20:36 -07003295 * we will be updating only the data blocks + inodes */
Dmitry Monakhovc4590012009-12-09 03:05:30 +03003296 ret += EXT3_MAXQUOTAS_TRANS_BLOCKS(inode->i_sb);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003297#endif
3298
3299 return ret;
3300}
3301
3302/*
3303 * The caller must have previously called ext3_reserve_inode_write().
3304 * Give this, we know that the caller already has write access to iloc->bh.
3305 */
3306int ext3_mark_iloc_dirty(handle_t *handle,
3307 struct inode *inode, struct ext3_iloc *iloc)
3308{
3309 int err = 0;
3310
3311 /* the do_update_inode consumes one bh->b_count */
3312 get_bh(iloc->bh);
3313
3314 /* ext3_do_update_inode() does journal_dirty_metadata */
3315 err = ext3_do_update_inode(handle, inode, iloc);
3316 put_bh(iloc->bh);
3317 return err;
3318}
3319
Mingming Caoae6ddcc2006-09-27 01:49:27 -07003320/*
Linus Torvalds1da177e2005-04-16 15:20:36 -07003321 * On success, We end up with an outstanding reference count against
Mingming Caoae6ddcc2006-09-27 01:49:27 -07003322 * iloc->bh. This _must_ be cleaned up later.
Linus Torvalds1da177e2005-04-16 15:20:36 -07003323 */
3324
3325int
Mingming Caoae6ddcc2006-09-27 01:49:27 -07003326ext3_reserve_inode_write(handle_t *handle, struct inode *inode,
Linus Torvalds1da177e2005-04-16 15:20:36 -07003327 struct ext3_iloc *iloc)
3328{
3329 int err = 0;
3330 if (handle) {
3331 err = ext3_get_inode_loc(inode, iloc);
3332 if (!err) {
3333 BUFFER_TRACE(iloc->bh, "get_write_access");
3334 err = ext3_journal_get_write_access(handle, iloc->bh);
3335 if (err) {
3336 brelse(iloc->bh);
3337 iloc->bh = NULL;
3338 }
3339 }
3340 }
3341 ext3_std_error(inode->i_sb, err);
3342 return err;
3343}
3344
3345/*
Andrew Mortond6859bf2006-03-26 01:38:03 -08003346 * What we do here is to mark the in-core inode as clean with respect to inode
3347 * dirtiness (it may still be data-dirty).
Linus Torvalds1da177e2005-04-16 15:20:36 -07003348 * This means that the in-core inode may be reaped by prune_icache
3349 * without having to perform any I/O. This is a very good thing,
3350 * because *any* task may call prune_icache - even ones which
3351 * have a transaction open against a different journal.
3352 *
3353 * Is this cheating? Not really. Sure, we haven't written the
3354 * inode out, but prune_icache isn't a user-visible syncing function.
3355 * Whenever the user wants stuff synced (sys_sync, sys_msync, sys_fsync)
3356 * we start and wait on commits.
3357 *
3358 * Is this efficient/effective? Well, we're being nice to the system
3359 * by cleaning up our inodes proactively so they can be reaped
3360 * without I/O. But we are potentially leaving up to five seconds'
3361 * worth of inodes floating about which prune_icache wants us to
3362 * write out. One way to fix that would be to get prune_icache()
3363 * to do a write_super() to free up some memory. It has the desired
3364 * effect.
3365 */
3366int ext3_mark_inode_dirty(handle_t *handle, struct inode *inode)
3367{
3368 struct ext3_iloc iloc;
3369 int err;
3370
3371 might_sleep();
3372 err = ext3_reserve_inode_write(handle, inode, &iloc);
3373 if (!err)
3374 err = ext3_mark_iloc_dirty(handle, inode, &iloc);
3375 return err;
3376}
3377
3378/*
Andrew Mortond6859bf2006-03-26 01:38:03 -08003379 * ext3_dirty_inode() is called from __mark_inode_dirty()
Linus Torvalds1da177e2005-04-16 15:20:36 -07003380 *
3381 * We're really interested in the case where a file is being extended.
3382 * i_size has been changed by generic_commit_write() and we thus need
3383 * to include the updated inode in the current transaction.
3384 *
Christoph Hellwig5dd40562010-03-03 09:05:00 -05003385 * Also, dquot_alloc_space() will always dirty the inode when blocks
Linus Torvalds1da177e2005-04-16 15:20:36 -07003386 * are allocated to the file.
3387 *
3388 * If the inode is marked synchronous, we don't honour that here - doing
3389 * so would cause a commit on atime updates, which we don't bother doing.
3390 * We handle synchronous inodes at the highest possible level.
3391 */
3392void ext3_dirty_inode(struct inode *inode)
3393{
3394 handle_t *current_handle = ext3_journal_current_handle();
3395 handle_t *handle;
3396
3397 handle = ext3_journal_start(inode, 2);
3398 if (IS_ERR(handle))
3399 goto out;
3400 if (current_handle &&
3401 current_handle->h_transaction != handle->h_transaction) {
3402 /* This task has a transaction open against a different fs */
3403 printk(KERN_EMERG "%s: transactions do not match!\n",
Harvey Harrisone05b6b52008-04-28 02:16:15 -07003404 __func__);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003405 } else {
3406 jbd_debug(5, "marking dirty. outer handle=%p\n",
3407 current_handle);
3408 ext3_mark_inode_dirty(handle, inode);
3409 }
3410 ext3_journal_stop(handle);
3411out:
3412 return;
3413}
3414
Andrew Mortond6859bf2006-03-26 01:38:03 -08003415#if 0
Mingming Caoae6ddcc2006-09-27 01:49:27 -07003416/*
Linus Torvalds1da177e2005-04-16 15:20:36 -07003417 * Bind an inode's backing buffer_head into this transaction, to prevent
3418 * it from being flushed to disk early. Unlike
3419 * ext3_reserve_inode_write, this leaves behind no bh reference and
3420 * returns no iloc structure, so the caller needs to repeat the iloc
3421 * lookup to mark the inode dirty later.
3422 */
Andrew Mortond6859bf2006-03-26 01:38:03 -08003423static int ext3_pin_inode(handle_t *handle, struct inode *inode)
Linus Torvalds1da177e2005-04-16 15:20:36 -07003424{
3425 struct ext3_iloc iloc;
3426
3427 int err = 0;
3428 if (handle) {
3429 err = ext3_get_inode_loc(inode, &iloc);
3430 if (!err) {
3431 BUFFER_TRACE(iloc.bh, "get_write_access");
3432 err = journal_get_write_access(handle, iloc.bh);
3433 if (!err)
Mingming Caoae6ddcc2006-09-27 01:49:27 -07003434 err = ext3_journal_dirty_metadata(handle,
Linus Torvalds1da177e2005-04-16 15:20:36 -07003435 iloc.bh);
3436 brelse(iloc.bh);
3437 }
3438 }
3439 ext3_std_error(inode->i_sb, err);
3440 return err;
3441}
3442#endif
3443
3444int ext3_change_inode_journal_flag(struct inode *inode, int val)
3445{
3446 journal_t *journal;
3447 handle_t *handle;
3448 int err;
3449
3450 /*
3451 * We have to be very careful here: changing a data block's
3452 * journaling status dynamically is dangerous. If we write a
3453 * data block to the journal, change the status and then delete
3454 * that block, we risk forgetting to revoke the old log record
3455 * from the journal and so a subsequent replay can corrupt data.
3456 * So, first we make sure that the journal is empty and that
3457 * nobody is changing anything.
3458 */
3459
3460 journal = EXT3_JOURNAL(inode);
Dave Hansene3a68e32007-07-15 23:41:14 -07003461 if (is_journal_aborted(journal))
Linus Torvalds1da177e2005-04-16 15:20:36 -07003462 return -EROFS;
3463
3464 journal_lock_updates(journal);
3465 journal_flush(journal);
3466
3467 /*
3468 * OK, there are no updates running now, and all cached data is
3469 * synced to disk. We are now in a completely consistent state
3470 * which doesn't have anything in the journal, and we know that
3471 * no filesystem updates are running, so it is safe to modify
3472 * the inode's in-core data-journaling state flag now.
3473 */
3474
3475 if (val)
3476 EXT3_I(inode)->i_flags |= EXT3_JOURNAL_DATA_FL;
3477 else
3478 EXT3_I(inode)->i_flags &= ~EXT3_JOURNAL_DATA_FL;
3479 ext3_set_aops(inode);
3480
3481 journal_unlock_updates(journal);
3482
3483 /* Finally we can mark the inode as dirty. */
3484
3485 handle = ext3_journal_start(inode, 1);
3486 if (IS_ERR(handle))
3487 return PTR_ERR(handle);
3488
3489 err = ext3_mark_inode_dirty(handle, inode);
3490 handle->h_sync = 1;
3491 ext3_journal_stop(handle);
3492 ext3_std_error(inode->i_sb, err);
3493
3494 return err;
3495}