blob: c5826c623e7af8e19aa0baf5829ce5e25fcc1f71 [file] [log] [blame]
Akira Fujita748de672009-06-17 19:24:03 -04001/*
2 * Copyright (c) 2008,2009 NEC Software Tohoku, Ltd.
3 * Written by Takashi Sato <t-sato@yk.jp.nec.com>
4 * Akira Fujita <a-fujita@rs.jp.nec.com>
5 *
6 * This program is free software; you can redistribute it and/or modify it
7 * under the terms of version 2.1 of the GNU Lesser General Public License
8 * as published by the Free Software Foundation.
9 *
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
14 */
15
16#include <linux/fs.h>
17#include <linux/quotaops.h>
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090018#include <linux/slab.h>
Akira Fujita748de672009-06-17 19:24:03 -040019#include "ext4_jbd2.h"
Akira Fujita748de672009-06-17 19:24:03 -040020#include "ext4.h"
21
Akira Fujitae8505972009-09-16 13:46:38 -040022/**
23 * get_ext_path - Find an extent path for designated logical block number.
24 *
25 * @inode: an inode which is searched
26 * @lblock: logical block number to find an extent path
27 * @path: pointer to an extent path pointer (for output)
28 *
29 * ext4_ext_find_extent wrapper. Return 0 on success, or a negative error value
30 * on failure.
31 */
32static inline int
33get_ext_path(struct inode *inode, ext4_lblk_t lblock,
34 struct ext4_ext_path **path)
35{
36 int ret = 0;
37
38 *path = ext4_ext_find_extent(inode, lblock, *path);
39 if (IS_ERR(*path)) {
40 ret = PTR_ERR(*path);
41 *path = NULL;
Akira Fujita347fa6f2009-09-16 14:25:07 -040042 } else if ((*path)[ext_depth(inode)].p_ext == NULL)
43 ret = -ENODATA;
44
Akira Fujitae8505972009-09-16 13:46:38 -040045 return ret;
46}
Akira Fujita748de672009-06-17 19:24:03 -040047
48/**
49 * copy_extent_status - Copy the extent's initialization status
50 *
51 * @src: an extent for getting initialize status
52 * @dest: an extent to be set the status
53 */
54static void
55copy_extent_status(struct ext4_extent *src, struct ext4_extent *dest)
56{
57 if (ext4_ext_is_uninitialized(src))
58 ext4_ext_mark_uninitialized(dest);
59 else
60 dest->ee_len = cpu_to_le16(ext4_ext_get_actual_len(dest));
61}
62
63/**
64 * mext_next_extent - Search for the next extent and set it to "extent"
65 *
66 * @inode: inode which is searched
67 * @path: this will obtain data for the next extent
68 * @extent: pointer to the next extent we have just gotten
69 *
70 * Search the next extent in the array of ext4_ext_path structure (@path)
71 * and set it to ext4_extent structure (@extent). In addition, the member of
72 * @path (->p_ext) also points the next extent. Return 0 on success, 1 if
73 * ext4_ext_path structure refers to the last extent, or a negative error
74 * value on failure.
75 */
76static int
77mext_next_extent(struct inode *inode, struct ext4_ext_path *path,
78 struct ext4_extent **extent)
79{
Akira Fujitafc04cb42009-11-23 07:24:43 -050080 struct ext4_extent_header *eh;
Akira Fujita748de672009-06-17 19:24:03 -040081 int ppos, leaf_ppos = path->p_depth;
82
83 ppos = leaf_ppos;
84 if (EXT_LAST_EXTENT(path[ppos].p_hdr) > path[ppos].p_ext) {
85 /* leaf block */
86 *extent = ++path[ppos].p_ext;
Theodore Ts'obf89d162010-10-27 21:30:14 -040087 path[ppos].p_block = ext4_ext_pblock(path[ppos].p_ext);
Akira Fujita748de672009-06-17 19:24:03 -040088 return 0;
89 }
90
91 while (--ppos >= 0) {
92 if (EXT_LAST_INDEX(path[ppos].p_hdr) >
93 path[ppos].p_idx) {
94 int cur_ppos = ppos;
95
96 /* index block */
97 path[ppos].p_idx++;
Theodore Ts'obf89d162010-10-27 21:30:14 -040098 path[ppos].p_block = ext4_idx_pblock(path[ppos].p_idx);
Akira Fujita748de672009-06-17 19:24:03 -040099 if (path[ppos+1].p_bh)
100 brelse(path[ppos+1].p_bh);
101 path[ppos+1].p_bh =
102 sb_bread(inode->i_sb, path[ppos].p_block);
103 if (!path[ppos+1].p_bh)
104 return -EIO;
105 path[ppos+1].p_hdr =
106 ext_block_hdr(path[ppos+1].p_bh);
107
108 /* Halfway index block */
109 while (++cur_ppos < leaf_ppos) {
110 path[cur_ppos].p_idx =
111 EXT_FIRST_INDEX(path[cur_ppos].p_hdr);
112 path[cur_ppos].p_block =
Theodore Ts'obf89d162010-10-27 21:30:14 -0400113 ext4_idx_pblock(path[cur_ppos].p_idx);
Akira Fujita748de672009-06-17 19:24:03 -0400114 if (path[cur_ppos+1].p_bh)
115 brelse(path[cur_ppos+1].p_bh);
116 path[cur_ppos+1].p_bh = sb_bread(inode->i_sb,
117 path[cur_ppos].p_block);
118 if (!path[cur_ppos+1].p_bh)
119 return -EIO;
120 path[cur_ppos+1].p_hdr =
121 ext_block_hdr(path[cur_ppos+1].p_bh);
122 }
123
Akira Fujitafc04cb42009-11-23 07:24:43 -0500124 path[leaf_ppos].p_ext = *extent = NULL;
125
126 eh = path[leaf_ppos].p_hdr;
127 if (le16_to_cpu(eh->eh_entries) == 0)
128 /* empty leaf is found */
129 return -ENODATA;
130
Akira Fujita748de672009-06-17 19:24:03 -0400131 /* leaf block */
132 path[leaf_ppos].p_ext = *extent =
133 EXT_FIRST_EXTENT(path[leaf_ppos].p_hdr);
Akira Fujitafc04cb42009-11-23 07:24:43 -0500134 path[leaf_ppos].p_block =
Theodore Ts'obf89d162010-10-27 21:30:14 -0400135 ext4_ext_pblock(path[leaf_ppos].p_ext);
Akira Fujita748de672009-06-17 19:24:03 -0400136 return 0;
137 }
138 }
139 /* We found the last extent */
140 return 1;
141}
142
143/**
Akira Fujita2147b1a2009-09-16 13:46:35 -0400144 * mext_check_null_inode - NULL check for two inodes
145 *
146 * If inode1 or inode2 is NULL, return -EIO. Otherwise, return 0.
147 */
148static int
149mext_check_null_inode(struct inode *inode1, struct inode *inode2,
Theodore Ts'oc398eda2010-07-27 11:56:40 -0400150 const char *function, unsigned int line)
Akira Fujita2147b1a2009-09-16 13:46:35 -0400151{
152 int ret = 0;
153
154 if (inode1 == NULL) {
Theodore Ts'oc398eda2010-07-27 11:56:40 -0400155 __ext4_error(inode2->i_sb, function, line,
Akira Fujita2147b1a2009-09-16 13:46:35 -0400156 "Both inodes should not be NULL: "
157 "inode1 NULL inode2 %lu", inode2->i_ino);
158 ret = -EIO;
159 } else if (inode2 == NULL) {
Theodore Ts'oc398eda2010-07-27 11:56:40 -0400160 __ext4_error(inode1->i_sb, function, line,
Akira Fujita2147b1a2009-09-16 13:46:35 -0400161 "Both inodes should not be NULL: "
162 "inode1 %lu inode2 NULL", inode1->i_ino);
163 ret = -EIO;
164 }
165 return ret;
166}
167
168/**
Akira Fujitafc04cb42009-11-23 07:24:43 -0500169 * double_down_write_data_sem - Acquire two inodes' write lock of i_data_sem
Akira Fujita748de672009-06-17 19:24:03 -0400170 *
171 * @orig_inode: original inode structure
172 * @donor_inode: donor inode structure
Akira Fujitafc04cb42009-11-23 07:24:43 -0500173 * Acquire write lock of i_data_sem of the two inodes (orig and donor) by
174 * i_ino order.
Akira Fujita748de672009-06-17 19:24:03 -0400175 */
176static void
Akira Fujitafc04cb42009-11-23 07:24:43 -0500177double_down_write_data_sem(struct inode *orig_inode, struct inode *donor_inode)
Akira Fujita748de672009-06-17 19:24:03 -0400178{
179 struct inode *first = orig_inode, *second = donor_inode;
180
Akira Fujita748de672009-06-17 19:24:03 -0400181 /*
182 * Use the inode number to provide the stable locking order instead
183 * of its address, because the C language doesn't guarantee you can
184 * compare pointers that don't come from the same array.
185 */
186 if (donor_inode->i_ino < orig_inode->i_ino) {
187 first = donor_inode;
188 second = orig_inode;
189 }
190
191 down_write(&EXT4_I(first)->i_data_sem);
Akira Fujita49bd22b2009-11-23 07:24:41 -0500192 down_write_nested(&EXT4_I(second)->i_data_sem, SINGLE_DEPTH_NESTING);
Akira Fujita748de672009-06-17 19:24:03 -0400193}
194
195/**
Akira Fujitafc04cb42009-11-23 07:24:43 -0500196 * double_up_write_data_sem - Release two inodes' write lock of i_data_sem
Akira Fujita748de672009-06-17 19:24:03 -0400197 *
198 * @orig_inode: original inode structure to be released its lock first
199 * @donor_inode: donor inode structure to be released its lock second
Akira Fujitafc04cb42009-11-23 07:24:43 -0500200 * Release write lock of i_data_sem of two inodes (orig and donor).
Akira Fujita748de672009-06-17 19:24:03 -0400201 */
202static void
Akira Fujitafc04cb42009-11-23 07:24:43 -0500203double_up_write_data_sem(struct inode *orig_inode, struct inode *donor_inode)
Akira Fujita748de672009-06-17 19:24:03 -0400204{
Akira Fujita748de672009-06-17 19:24:03 -0400205 up_write(&EXT4_I(orig_inode)->i_data_sem);
206 up_write(&EXT4_I(donor_inode)->i_data_sem);
207}
208
209/**
210 * mext_insert_across_blocks - Insert extents across leaf block
211 *
212 * @handle: journal handle
213 * @orig_inode: original inode
214 * @o_start: first original extent to be changed
215 * @o_end: last original extent to be changed
216 * @start_ext: first new extent to be inserted
217 * @new_ext: middle of new extent to be inserted
218 * @end_ext: last new extent to be inserted
219 *
220 * Allocate a new leaf block and insert extents into it. Return 0 on success,
221 * or a negative error value on failure.
222 */
223static int
224mext_insert_across_blocks(handle_t *handle, struct inode *orig_inode,
225 struct ext4_extent *o_start, struct ext4_extent *o_end,
226 struct ext4_extent *start_ext, struct ext4_extent *new_ext,
227 struct ext4_extent *end_ext)
228{
229 struct ext4_ext_path *orig_path = NULL;
230 ext4_lblk_t eblock = 0;
231 int new_flag = 0;
232 int end_flag = 0;
233 int err = 0;
234
235 if (start_ext->ee_len && new_ext->ee_len && end_ext->ee_len) {
236 if (o_start == o_end) {
237
238 /* start_ext new_ext end_ext
239 * donor |---------|-----------|--------|
240 * orig |------------------------------|
241 */
242 end_flag = 1;
243 } else {
244
245 /* start_ext new_ext end_ext
246 * donor |---------|----------|---------|
247 * orig |---------------|--------------|
248 */
249 o_end->ee_block = end_ext->ee_block;
250 o_end->ee_len = end_ext->ee_len;
Theodore Ts'obf89d162010-10-27 21:30:14 -0400251 ext4_ext_store_pblock(o_end, ext4_ext_pblock(end_ext));
Akira Fujita748de672009-06-17 19:24:03 -0400252 }
253
254 o_start->ee_len = start_ext->ee_len;
Akira Fujita5fd52492010-03-04 00:31:06 -0500255 eblock = le32_to_cpu(start_ext->ee_block);
Akira Fujita748de672009-06-17 19:24:03 -0400256 new_flag = 1;
257
258 } else if (start_ext->ee_len && new_ext->ee_len &&
259 !end_ext->ee_len && o_start == o_end) {
260
261 /* start_ext new_ext
262 * donor |--------------|---------------|
263 * orig |------------------------------|
264 */
265 o_start->ee_len = start_ext->ee_len;
Akira Fujita5fd52492010-03-04 00:31:06 -0500266 eblock = le32_to_cpu(start_ext->ee_block);
Akira Fujita748de672009-06-17 19:24:03 -0400267 new_flag = 1;
268
269 } else if (!start_ext->ee_len && new_ext->ee_len &&
270 end_ext->ee_len && o_start == o_end) {
271
272 /* new_ext end_ext
273 * donor |--------------|---------------|
274 * orig |------------------------------|
275 */
276 o_end->ee_block = end_ext->ee_block;
277 o_end->ee_len = end_ext->ee_len;
Theodore Ts'obf89d162010-10-27 21:30:14 -0400278 ext4_ext_store_pblock(o_end, ext4_ext_pblock(end_ext));
Akira Fujita748de672009-06-17 19:24:03 -0400279
280 /*
281 * Set 0 to the extent block if new_ext was
282 * the first block.
283 */
284 if (new_ext->ee_block)
285 eblock = le32_to_cpu(new_ext->ee_block);
286
287 new_flag = 1;
288 } else {
289 ext4_debug("ext4 move extent: Unexpected insert case\n");
290 return -EIO;
291 }
292
293 if (new_flag) {
Akira Fujitae8505972009-09-16 13:46:38 -0400294 err = get_ext_path(orig_inode, eblock, &orig_path);
Akira Fujita347fa6f2009-09-16 14:25:07 -0400295 if (err)
Akira Fujita748de672009-06-17 19:24:03 -0400296 goto out;
297
298 if (ext4_ext_insert_extent(handle, orig_inode,
Mingming Cao00314622009-09-28 15:49:08 -0400299 orig_path, new_ext, 0))
Akira Fujita748de672009-06-17 19:24:03 -0400300 goto out;
301 }
302
303 if (end_flag) {
Akira Fujitae8505972009-09-16 13:46:38 -0400304 err = get_ext_path(orig_inode,
305 le32_to_cpu(end_ext->ee_block) - 1, &orig_path);
Akira Fujita347fa6f2009-09-16 14:25:07 -0400306 if (err)
Akira Fujita748de672009-06-17 19:24:03 -0400307 goto out;
308
309 if (ext4_ext_insert_extent(handle, orig_inode,
Mingming Cao00314622009-09-28 15:49:08 -0400310 orig_path, end_ext, 0))
Akira Fujita748de672009-06-17 19:24:03 -0400311 goto out;
312 }
313out:
314 if (orig_path) {
315 ext4_ext_drop_refs(orig_path);
316 kfree(orig_path);
317 }
318
319 return err;
320
321}
322
323/**
324 * mext_insert_inside_block - Insert new extent to the extent block
325 *
326 * @o_start: first original extent to be moved
327 * @o_end: last original extent to be moved
328 * @start_ext: first new extent to be inserted
329 * @new_ext: middle of new extent to be inserted
330 * @end_ext: last new extent to be inserted
331 * @eh: extent header of target leaf block
332 * @range_to_move: used to decide how to insert extent
333 *
334 * Insert extents into the leaf block. The extent (@o_start) is overwritten
335 * by inserted extents.
336 */
337static void
338mext_insert_inside_block(struct ext4_extent *o_start,
339 struct ext4_extent *o_end,
340 struct ext4_extent *start_ext,
341 struct ext4_extent *new_ext,
342 struct ext4_extent *end_ext,
343 struct ext4_extent_header *eh,
344 int range_to_move)
345{
346 int i = 0;
347 unsigned long len;
348
349 /* Move the existing extents */
350 if (range_to_move && o_end < EXT_LAST_EXTENT(eh)) {
351 len = (unsigned long)(EXT_LAST_EXTENT(eh) + 1) -
352 (unsigned long)(o_end + 1);
353 memmove(o_end + 1 + range_to_move, o_end + 1, len);
354 }
355
356 /* Insert start entry */
357 if (start_ext->ee_len)
358 o_start[i++].ee_len = start_ext->ee_len;
359
360 /* Insert new entry */
361 if (new_ext->ee_len) {
362 o_start[i] = *new_ext;
Theodore Ts'obf89d162010-10-27 21:30:14 -0400363 ext4_ext_store_pblock(&o_start[i++], ext4_ext_pblock(new_ext));
Akira Fujita748de672009-06-17 19:24:03 -0400364 }
365
366 /* Insert end entry */
367 if (end_ext->ee_len)
368 o_start[i] = *end_ext;
369
370 /* Increment the total entries counter on the extent block */
371 le16_add_cpu(&eh->eh_entries, range_to_move);
372}
373
374/**
375 * mext_insert_extents - Insert new extent
376 *
377 * @handle: journal handle
378 * @orig_inode: original inode
379 * @orig_path: path indicates first extent to be changed
380 * @o_start: first original extent to be changed
381 * @o_end: last original extent to be changed
382 * @start_ext: first new extent to be inserted
383 * @new_ext: middle of new extent to be inserted
384 * @end_ext: last new extent to be inserted
385 *
386 * Call the function to insert extents. If we cannot add more extents into
387 * the leaf block, we call mext_insert_across_blocks() to create a
388 * new leaf block. Otherwise call mext_insert_inside_block(). Return 0
389 * on success, or a negative error value on failure.
390 */
391static int
392mext_insert_extents(handle_t *handle, struct inode *orig_inode,
393 struct ext4_ext_path *orig_path,
394 struct ext4_extent *o_start,
395 struct ext4_extent *o_end,
396 struct ext4_extent *start_ext,
397 struct ext4_extent *new_ext,
398 struct ext4_extent *end_ext)
399{
400 struct ext4_extent_header *eh;
401 unsigned long need_slots, slots_range;
402 int range_to_move, depth, ret;
403
404 /*
405 * The extents need to be inserted
406 * start_extent + new_extent + end_extent.
407 */
408 need_slots = (start_ext->ee_len ? 1 : 0) + (end_ext->ee_len ? 1 : 0) +
409 (new_ext->ee_len ? 1 : 0);
410
411 /* The number of slots between start and end */
412 slots_range = ((unsigned long)(o_end + 1) - (unsigned long)o_start + 1)
413 / sizeof(struct ext4_extent);
414
415 /* Range to move the end of extent */
416 range_to_move = need_slots - slots_range;
417 depth = orig_path->p_depth;
418 orig_path += depth;
419 eh = orig_path->p_hdr;
420
421 if (depth) {
422 /* Register to journal */
423 ret = ext4_journal_get_write_access(handle, orig_path->p_bh);
424 if (ret)
425 return ret;
426 }
427
428 /* Expansion */
429 if (range_to_move > 0 &&
430 (range_to_move > le16_to_cpu(eh->eh_max)
431 - le16_to_cpu(eh->eh_entries))) {
432
433 ret = mext_insert_across_blocks(handle, orig_inode, o_start,
434 o_end, start_ext, new_ext, end_ext);
435 if (ret < 0)
436 return ret;
437 } else
438 mext_insert_inside_block(o_start, o_end, start_ext, new_ext,
439 end_ext, eh, range_to_move);
440
441 if (depth) {
442 ret = ext4_handle_dirty_metadata(handle, orig_inode,
443 orig_path->p_bh);
444 if (ret)
445 return ret;
446 } else {
447 ret = ext4_mark_inode_dirty(handle, orig_inode);
448 if (ret < 0)
449 return ret;
450 }
451
452 return 0;
453}
454
455/**
456 * mext_leaf_block - Move one leaf extent block into the inode.
457 *
458 * @handle: journal handle
459 * @orig_inode: original inode
460 * @orig_path: path indicates first extent to be changed
461 * @dext: donor extent
462 * @from: start offset on the target file
463 *
464 * In order to insert extents into the leaf block, we must divide the extent
465 * in the leaf block into three extents. The one is located to be inserted
466 * extents, and the others are located around it.
467 *
468 * Therefore, this function creates structures to save extents of the leaf
469 * block, and inserts extents by calling mext_insert_extents() with
470 * created extents. Return 0 on success, or a negative error value on failure.
471 */
472static int
473mext_leaf_block(handle_t *handle, struct inode *orig_inode,
474 struct ext4_ext_path *orig_path, struct ext4_extent *dext,
475 ext4_lblk_t *from)
476{
477 struct ext4_extent *oext, *o_start, *o_end, *prev_ext;
478 struct ext4_extent new_ext, start_ext, end_ext;
479 ext4_lblk_t new_ext_end;
Akira Fujita748de672009-06-17 19:24:03 -0400480 int oext_alen, new_ext_alen, end_ext_alen;
481 int depth = ext_depth(orig_inode);
482 int ret;
483
Steven Liuc26d0ba2010-05-11 00:00:00 -0400484 start_ext.ee_block = end_ext.ee_block = 0;
Akira Fujita748de672009-06-17 19:24:03 -0400485 o_start = o_end = oext = orig_path[depth].p_ext;
486 oext_alen = ext4_ext_get_actual_len(oext);
487 start_ext.ee_len = end_ext.ee_len = 0;
488
489 new_ext.ee_block = cpu_to_le32(*from);
Theodore Ts'obf89d162010-10-27 21:30:14 -0400490 ext4_ext_store_pblock(&new_ext, ext4_ext_pblock(dext));
Akira Fujita748de672009-06-17 19:24:03 -0400491 new_ext.ee_len = dext->ee_len;
492 new_ext_alen = ext4_ext_get_actual_len(&new_ext);
493 new_ext_end = le32_to_cpu(new_ext.ee_block) + new_ext_alen - 1;
Akira Fujita748de672009-06-17 19:24:03 -0400494
495 /*
496 * Case: original extent is first
497 * oext |--------|
498 * new_ext |--|
499 * start_ext |--|
500 */
501 if (le32_to_cpu(oext->ee_block) < le32_to_cpu(new_ext.ee_block) &&
502 le32_to_cpu(new_ext.ee_block) <
503 le32_to_cpu(oext->ee_block) + oext_alen) {
504 start_ext.ee_len = cpu_to_le16(le32_to_cpu(new_ext.ee_block) -
505 le32_to_cpu(oext->ee_block));
Akira Fujita5fd52492010-03-04 00:31:06 -0500506 start_ext.ee_block = oext->ee_block;
Akira Fujita748de672009-06-17 19:24:03 -0400507 copy_extent_status(oext, &start_ext);
508 } else if (oext > EXT_FIRST_EXTENT(orig_path[depth].p_hdr)) {
509 prev_ext = oext - 1;
510 /*
511 * We can merge new_ext into previous extent,
512 * if these are contiguous and same extent type.
513 */
514 if (ext4_can_extents_be_merged(orig_inode, prev_ext,
515 &new_ext)) {
516 o_start = prev_ext;
517 start_ext.ee_len = cpu_to_le16(
518 ext4_ext_get_actual_len(prev_ext) +
519 new_ext_alen);
Akira Fujita5fd52492010-03-04 00:31:06 -0500520 start_ext.ee_block = oext->ee_block;
Akira Fujita748de672009-06-17 19:24:03 -0400521 copy_extent_status(prev_ext, &start_ext);
522 new_ext.ee_len = 0;
523 }
524 }
525
526 /*
527 * Case: new_ext_end must be less than oext
528 * oext |-----------|
529 * new_ext |-------|
530 */
Akira Fujita2147b1a2009-09-16 13:46:35 -0400531 if (le32_to_cpu(oext->ee_block) + oext_alen - 1 < new_ext_end) {
Theodore Ts'o24676da2010-05-16 21:00:00 -0400532 EXT4_ERROR_INODE(orig_inode,
Akira Fujita2147b1a2009-09-16 13:46:35 -0400533 "new_ext_end(%u) should be less than or equal to "
534 "oext->ee_block(%u) + oext_alen(%d) - 1",
535 new_ext_end, le32_to_cpu(oext->ee_block),
536 oext_alen);
537 ret = -EIO;
538 goto out;
539 }
Akira Fujita748de672009-06-17 19:24:03 -0400540
541 /*
542 * Case: new_ext is smaller than original extent
543 * oext |---------------|
544 * new_ext |-----------|
545 * end_ext |---|
546 */
547 if (le32_to_cpu(oext->ee_block) <= new_ext_end &&
548 new_ext_end < le32_to_cpu(oext->ee_block) + oext_alen - 1) {
549 end_ext.ee_len =
550 cpu_to_le16(le32_to_cpu(oext->ee_block) +
551 oext_alen - 1 - new_ext_end);
552 copy_extent_status(oext, &end_ext);
553 end_ext_alen = ext4_ext_get_actual_len(&end_ext);
554 ext4_ext_store_pblock(&end_ext,
Theodore Ts'obf89d162010-10-27 21:30:14 -0400555 (ext4_ext_pblock(o_end) + oext_alen - end_ext_alen));
Akira Fujita748de672009-06-17 19:24:03 -0400556 end_ext.ee_block =
557 cpu_to_le32(le32_to_cpu(o_end->ee_block) +
558 oext_alen - end_ext_alen);
559 }
560
561 ret = mext_insert_extents(handle, orig_inode, orig_path, o_start,
562 o_end, &start_ext, &new_ext, &end_ext);
Akira Fujita2147b1a2009-09-16 13:46:35 -0400563out:
Akira Fujita748de672009-06-17 19:24:03 -0400564 return ret;
565}
566
567/**
568 * mext_calc_swap_extents - Calculate extents for extent swapping.
569 *
570 * @tmp_dext: the extent that will belong to the original inode
571 * @tmp_oext: the extent that will belong to the donor inode
572 * @orig_off: block offset of original inode
573 * @donor_off: block offset of donor inode
Akira Fujita92c28152009-11-23 07:24:50 -0500574 * @max_count: the maximum length of extents
Akira Fujitac40ce3c2009-09-16 14:25:39 -0400575 *
576 * Return 0 on success, or a negative error value on failure.
Akira Fujita748de672009-06-17 19:24:03 -0400577 */
Akira Fujitac40ce3c2009-09-16 14:25:39 -0400578static int
Akira Fujita748de672009-06-17 19:24:03 -0400579mext_calc_swap_extents(struct ext4_extent *tmp_dext,
580 struct ext4_extent *tmp_oext,
581 ext4_lblk_t orig_off, ext4_lblk_t donor_off,
582 ext4_lblk_t max_count)
583{
584 ext4_lblk_t diff, orig_diff;
585 struct ext4_extent dext_old, oext_old;
586
Akira Fujitac40ce3c2009-09-16 14:25:39 -0400587 BUG_ON(orig_off != donor_off);
588
589 /* original and donor extents have to cover the same block offset */
590 if (orig_off < le32_to_cpu(tmp_oext->ee_block) ||
591 le32_to_cpu(tmp_oext->ee_block) +
592 ext4_ext_get_actual_len(tmp_oext) - 1 < orig_off)
593 return -ENODATA;
594
595 if (orig_off < le32_to_cpu(tmp_dext->ee_block) ||
596 le32_to_cpu(tmp_dext->ee_block) +
597 ext4_ext_get_actual_len(tmp_dext) - 1 < orig_off)
598 return -ENODATA;
599
Akira Fujita748de672009-06-17 19:24:03 -0400600 dext_old = *tmp_dext;
601 oext_old = *tmp_oext;
602
603 /* When tmp_dext is too large, pick up the target range. */
604 diff = donor_off - le32_to_cpu(tmp_dext->ee_block);
605
Theodore Ts'obf89d162010-10-27 21:30:14 -0400606 ext4_ext_store_pblock(tmp_dext, ext4_ext_pblock(tmp_dext) + diff);
Akira Fujita748de672009-06-17 19:24:03 -0400607 tmp_dext->ee_block =
608 cpu_to_le32(le32_to_cpu(tmp_dext->ee_block) + diff);
609 tmp_dext->ee_len = cpu_to_le16(le16_to_cpu(tmp_dext->ee_len) - diff);
610
611 if (max_count < ext4_ext_get_actual_len(tmp_dext))
612 tmp_dext->ee_len = cpu_to_le16(max_count);
613
614 orig_diff = orig_off - le32_to_cpu(tmp_oext->ee_block);
Theodore Ts'obf89d162010-10-27 21:30:14 -0400615 ext4_ext_store_pblock(tmp_oext, ext4_ext_pblock(tmp_oext) + orig_diff);
Akira Fujita748de672009-06-17 19:24:03 -0400616
617 /* Adjust extent length if donor extent is larger than orig */
618 if (ext4_ext_get_actual_len(tmp_dext) >
619 ext4_ext_get_actual_len(tmp_oext) - orig_diff)
620 tmp_dext->ee_len = cpu_to_le16(le16_to_cpu(tmp_oext->ee_len) -
621 orig_diff);
622
623 tmp_oext->ee_len = cpu_to_le16(ext4_ext_get_actual_len(tmp_dext));
624
625 copy_extent_status(&oext_old, tmp_dext);
626 copy_extent_status(&dext_old, tmp_oext);
Akira Fujitac40ce3c2009-09-16 14:25:39 -0400627
628 return 0;
Akira Fujita748de672009-06-17 19:24:03 -0400629}
630
631/**
632 * mext_replace_branches - Replace original extents with new extents
633 *
634 * @handle: journal handle
635 * @orig_inode: original inode
636 * @donor_inode: donor inode
637 * @from: block offset of orig_inode
638 * @count: block count to be replaced
Akira Fujitaf868a482009-11-23 07:25:48 -0500639 * @err: pointer to save return value
Akira Fujita748de672009-06-17 19:24:03 -0400640 *
641 * Replace original inode extents and donor inode extents page by page.
642 * We implement this replacement in the following three steps:
643 * 1. Save the block information of original and donor inodes into
644 * dummy extents.
645 * 2. Change the block information of original inode to point at the
646 * donor inode blocks.
647 * 3. Change the block information of donor inode to point at the saved
648 * original inode blocks in the dummy extents.
649 *
Akira Fujitaf868a482009-11-23 07:25:48 -0500650 * Return replaced block count.
Akira Fujita748de672009-06-17 19:24:03 -0400651 */
652static int
653mext_replace_branches(handle_t *handle, struct inode *orig_inode,
654 struct inode *donor_inode, ext4_lblk_t from,
Akira Fujitaf868a482009-11-23 07:25:48 -0500655 ext4_lblk_t count, int *err)
Akira Fujita748de672009-06-17 19:24:03 -0400656{
657 struct ext4_ext_path *orig_path = NULL;
658 struct ext4_ext_path *donor_path = NULL;
659 struct ext4_extent *oext, *dext;
660 struct ext4_extent tmp_dext, tmp_oext;
661 ext4_lblk_t orig_off = from, donor_off = from;
Akira Fujita748de672009-06-17 19:24:03 -0400662 int depth;
663 int replaced_count = 0;
664 int dext_alen;
665
Akira Fujitaac48b0a2009-11-24 10:31:56 -0500666 /* Protect extent trees against block allocations via delalloc */
667 double_down_write_data_sem(orig_inode, donor_inode);
668
Akira Fujita748de672009-06-17 19:24:03 -0400669 /* Get the original extent for the block "orig_off" */
Akira Fujitaf868a482009-11-23 07:25:48 -0500670 *err = get_ext_path(orig_inode, orig_off, &orig_path);
671 if (*err)
Akira Fujita748de672009-06-17 19:24:03 -0400672 goto out;
673
674 /* Get the donor extent for the head */
Akira Fujitaf868a482009-11-23 07:25:48 -0500675 *err = get_ext_path(donor_inode, donor_off, &donor_path);
676 if (*err)
Akira Fujita748de672009-06-17 19:24:03 -0400677 goto out;
678 depth = ext_depth(orig_inode);
679 oext = orig_path[depth].p_ext;
680 tmp_oext = *oext;
681
682 depth = ext_depth(donor_inode);
683 dext = donor_path[depth].p_ext;
684 tmp_dext = *dext;
685
Akira Fujitaf868a482009-11-23 07:25:48 -0500686 *err = mext_calc_swap_extents(&tmp_dext, &tmp_oext, orig_off,
Akira Fujita748de672009-06-17 19:24:03 -0400687 donor_off, count);
Akira Fujitaf868a482009-11-23 07:25:48 -0500688 if (*err)
Akira Fujitac40ce3c2009-09-16 14:25:39 -0400689 goto out;
Akira Fujita748de672009-06-17 19:24:03 -0400690
691 /* Loop for the donor extents */
692 while (1) {
693 /* The extent for donor must be found. */
Akira Fujita2147b1a2009-09-16 13:46:35 -0400694 if (!dext) {
Theodore Ts'o24676da2010-05-16 21:00:00 -0400695 EXT4_ERROR_INODE(donor_inode,
Akira Fujita2147b1a2009-09-16 13:46:35 -0400696 "The extent for donor must be found");
Akira Fujitaf868a482009-11-23 07:25:48 -0500697 *err = -EIO;
Akira Fujita2147b1a2009-09-16 13:46:35 -0400698 goto out;
699 } else if (donor_off != le32_to_cpu(tmp_dext.ee_block)) {
Theodore Ts'o24676da2010-05-16 21:00:00 -0400700 EXT4_ERROR_INODE(donor_inode,
Akira Fujita2147b1a2009-09-16 13:46:35 -0400701 "Donor offset(%u) and the first block of donor "
702 "extent(%u) should be equal",
703 donor_off,
704 le32_to_cpu(tmp_dext.ee_block));
Akira Fujitaf868a482009-11-23 07:25:48 -0500705 *err = -EIO;
Akira Fujita2147b1a2009-09-16 13:46:35 -0400706 goto out;
707 }
Akira Fujita748de672009-06-17 19:24:03 -0400708
709 /* Set donor extent to orig extent */
Akira Fujitaf868a482009-11-23 07:25:48 -0500710 *err = mext_leaf_block(handle, orig_inode,
Akira Fujita748de672009-06-17 19:24:03 -0400711 orig_path, &tmp_dext, &orig_off);
Akira Fujitaf868a482009-11-23 07:25:48 -0500712 if (*err)
Akira Fujita748de672009-06-17 19:24:03 -0400713 goto out;
714
715 /* Set orig extent to donor extent */
Akira Fujitaf868a482009-11-23 07:25:48 -0500716 *err = mext_leaf_block(handle, donor_inode,
Akira Fujita748de672009-06-17 19:24:03 -0400717 donor_path, &tmp_oext, &donor_off);
Akira Fujitaf868a482009-11-23 07:25:48 -0500718 if (*err)
Akira Fujita748de672009-06-17 19:24:03 -0400719 goto out;
720
721 dext_alen = ext4_ext_get_actual_len(&tmp_dext);
722 replaced_count += dext_alen;
723 donor_off += dext_alen;
724 orig_off += dext_alen;
725
726 /* Already moved the expected blocks */
727 if (replaced_count >= count)
728 break;
729
730 if (orig_path)
731 ext4_ext_drop_refs(orig_path);
Akira Fujitaf868a482009-11-23 07:25:48 -0500732 *err = get_ext_path(orig_inode, orig_off, &orig_path);
733 if (*err)
Akira Fujita748de672009-06-17 19:24:03 -0400734 goto out;
735 depth = ext_depth(orig_inode);
736 oext = orig_path[depth].p_ext;
Akira Fujita748de672009-06-17 19:24:03 -0400737 tmp_oext = *oext;
738
739 if (donor_path)
740 ext4_ext_drop_refs(donor_path);
Akira Fujitaf868a482009-11-23 07:25:48 -0500741 *err = get_ext_path(donor_inode, donor_off, &donor_path);
742 if (*err)
Akira Fujita748de672009-06-17 19:24:03 -0400743 goto out;
744 depth = ext_depth(donor_inode);
745 dext = donor_path[depth].p_ext;
Akira Fujita748de672009-06-17 19:24:03 -0400746 tmp_dext = *dext;
747
Akira Fujitaf868a482009-11-23 07:25:48 -0500748 *err = mext_calc_swap_extents(&tmp_dext, &tmp_oext, orig_off,
Akira Fujitac40ce3c2009-09-16 14:25:39 -0400749 donor_off, count - replaced_count);
Akira Fujitaf868a482009-11-23 07:25:48 -0500750 if (*err)
Akira Fujitac40ce3c2009-09-16 14:25:39 -0400751 goto out;
Akira Fujita748de672009-06-17 19:24:03 -0400752 }
753
754out:
755 if (orig_path) {
756 ext4_ext_drop_refs(orig_path);
757 kfree(orig_path);
758 }
759 if (donor_path) {
760 ext4_ext_drop_refs(donor_path);
761 kfree(donor_path);
762 }
763
Akira Fujitaac48b0a2009-11-24 10:31:56 -0500764 ext4_ext_invalidate_cache(orig_inode);
765 ext4_ext_invalidate_cache(donor_inode);
766
767 double_up_write_data_sem(orig_inode, donor_inode);
768
Akira Fujitaf868a482009-11-23 07:25:48 -0500769 return replaced_count;
Akira Fujita748de672009-06-17 19:24:03 -0400770}
771
772/**
773 * move_extent_per_page - Move extent data per page
774 *
775 * @o_filp: file structure of original file
776 * @donor_inode: donor inode
777 * @orig_page_offset: page index on original file
778 * @data_offset_in_page: block index where data swapping starts
779 * @block_len_in_page: the number of blocks to be swapped
780 * @uninit: orig extent is uninitialized or not
Akira Fujitaf868a482009-11-23 07:25:48 -0500781 * @err: pointer to save return value
Akira Fujita748de672009-06-17 19:24:03 -0400782 *
783 * Save the data in original inode blocks and replace original inode extents
784 * with donor inode extents by calling mext_replace_branches().
Akira Fujitaf868a482009-11-23 07:25:48 -0500785 * Finally, write out the saved data in new original inode blocks. Return
786 * replaced block count.
Akira Fujita748de672009-06-17 19:24:03 -0400787 */
788static int
Akira Fujita44fc48f2009-09-05 23:12:41 -0400789move_extent_per_page(struct file *o_filp, struct inode *donor_inode,
Akira Fujita748de672009-06-17 19:24:03 -0400790 pgoff_t orig_page_offset, int data_offset_in_page,
Akira Fujitaf868a482009-11-23 07:25:48 -0500791 int block_len_in_page, int uninit, int *err)
Akira Fujita748de672009-06-17 19:24:03 -0400792{
793 struct inode *orig_inode = o_filp->f_dentry->d_inode;
794 struct address_space *mapping = orig_inode->i_mapping;
795 struct buffer_head *bh;
796 struct page *page = NULL;
797 const struct address_space_operations *a_ops = mapping->a_ops;
798 handle_t *handle;
799 ext4_lblk_t orig_blk_offset;
800 long long offs = orig_page_offset << PAGE_CACHE_SHIFT;
801 unsigned long blocksize = orig_inode->i_sb->s_blocksize;
802 unsigned int w_flags = 0;
Akira Fujitaf868a482009-11-23 07:25:48 -0500803 unsigned int tmp_data_size, data_size, replaced_size;
Akira Fujita748de672009-06-17 19:24:03 -0400804 void *fsdata;
Akira Fujitaf868a482009-11-23 07:25:48 -0500805 int i, jblocks;
806 int err2 = 0;
807 int replaced_count = 0;
Akira Fujita748de672009-06-17 19:24:03 -0400808 int blocks_per_page = PAGE_CACHE_SIZE >> orig_inode->i_blkbits;
809
810 /*
811 * It needs twice the amount of ordinary journal buffers because
812 * inode and donor_inode may change each different metadata blocks.
813 */
814 jblocks = ext4_writepage_trans_blocks(orig_inode) * 2;
815 handle = ext4_journal_start(orig_inode, jblocks);
816 if (IS_ERR(handle)) {
Akira Fujitaf868a482009-11-23 07:25:48 -0500817 *err = PTR_ERR(handle);
818 return 0;
Akira Fujita748de672009-06-17 19:24:03 -0400819 }
820
821 if (segment_eq(get_fs(), KERNEL_DS))
822 w_flags |= AOP_FLAG_UNINTERRUPTIBLE;
823
824 orig_blk_offset = orig_page_offset * blocks_per_page +
825 data_offset_in_page;
826
827 /*
828 * If orig extent is uninitialized one,
829 * it's not necessary force the page into memory
830 * and then force it to be written out again.
831 * Just swap data blocks between orig and donor.
832 */
833 if (uninit) {
Akira Fujitaf868a482009-11-23 07:25:48 -0500834 replaced_count = mext_replace_branches(handle, orig_inode,
835 donor_inode, orig_blk_offset,
836 block_len_in_page, err);
Akira Fujita748de672009-06-17 19:24:03 -0400837 goto out2;
838 }
839
840 offs = (long long)orig_blk_offset << orig_inode->i_blkbits;
841
Akira Fujitaf868a482009-11-23 07:25:48 -0500842 /* Calculate data_size */
Akira Fujita748de672009-06-17 19:24:03 -0400843 if ((orig_blk_offset + block_len_in_page - 1) ==
844 ((orig_inode->i_size - 1) >> orig_inode->i_blkbits)) {
845 /* Replace the last block */
Akira Fujitaf868a482009-11-23 07:25:48 -0500846 tmp_data_size = orig_inode->i_size & (blocksize - 1);
Akira Fujita748de672009-06-17 19:24:03 -0400847 /*
Akira Fujitaf868a482009-11-23 07:25:48 -0500848 * If data_size equal zero, it shows data_size is multiples of
Akira Fujita748de672009-06-17 19:24:03 -0400849 * blocksize. So we set appropriate value.
850 */
Akira Fujitaf868a482009-11-23 07:25:48 -0500851 if (tmp_data_size == 0)
852 tmp_data_size = blocksize;
Akira Fujita748de672009-06-17 19:24:03 -0400853
Akira Fujitaf868a482009-11-23 07:25:48 -0500854 data_size = tmp_data_size +
Akira Fujita748de672009-06-17 19:24:03 -0400855 ((block_len_in_page - 1) << orig_inode->i_blkbits);
Akira Fujitaf868a482009-11-23 07:25:48 -0500856 } else
857 data_size = block_len_in_page << orig_inode->i_blkbits;
Akira Fujita748de672009-06-17 19:24:03 -0400858
Akira Fujitaf868a482009-11-23 07:25:48 -0500859 replaced_size = data_size;
860
861 *err = a_ops->write_begin(o_filp, mapping, offs, data_size, w_flags,
Akira Fujita748de672009-06-17 19:24:03 -0400862 &page, &fsdata);
Akira Fujitaf868a482009-11-23 07:25:48 -0500863 if (unlikely(*err < 0))
Akira Fujita748de672009-06-17 19:24:03 -0400864 goto out;
865
866 if (!PageUptodate(page)) {
867 mapping->a_ops->readpage(o_filp, page);
868 lock_page(page);
869 }
870
871 /*
872 * try_to_release_page() doesn't call releasepage in writeback mode.
873 * We should care about the order of writing to the same file
874 * by multiple move extent processes.
875 * It needs to call wait_on_page_writeback() to wait for the
876 * writeback of the page.
877 */
Darrick J. Wong7cb1a532011-05-18 13:53:20 -0400878 wait_on_page_writeback(page);
Akira Fujita748de672009-06-17 19:24:03 -0400879
880 /* Release old bh and drop refs */
881 try_to_release_page(page, 0);
882
Akira Fujitaf868a482009-11-23 07:25:48 -0500883 replaced_count = mext_replace_branches(handle, orig_inode, donor_inode,
884 orig_blk_offset, block_len_in_page,
885 &err2);
886 if (err2) {
887 if (replaced_count) {
888 block_len_in_page = replaced_count;
889 replaced_size =
890 block_len_in_page << orig_inode->i_blkbits;
Akira Fujitaac48b0a2009-11-24 10:31:56 -0500891 } else
Akira Fujitaf868a482009-11-23 07:25:48 -0500892 goto out;
893 }
Akira Fujita748de672009-06-17 19:24:03 -0400894
Akira Fujita748de672009-06-17 19:24:03 -0400895 if (!page_has_buffers(page))
896 create_empty_buffers(page, 1 << orig_inode->i_blkbits, 0);
897
898 bh = page_buffers(page);
899 for (i = 0; i < data_offset_in_page; i++)
900 bh = bh->b_this_page;
901
902 for (i = 0; i < block_len_in_page; i++) {
Akira Fujitaf868a482009-11-23 07:25:48 -0500903 *err = ext4_get_block(orig_inode,
Akira Fujita748de672009-06-17 19:24:03 -0400904 (sector_t)(orig_blk_offset + i), bh, 0);
Akira Fujitaf868a482009-11-23 07:25:48 -0500905 if (*err < 0)
Akira Fujita748de672009-06-17 19:24:03 -0400906 goto out;
907
908 if (bh->b_this_page != NULL)
909 bh = bh->b_this_page;
910 }
911
Akira Fujitaf868a482009-11-23 07:25:48 -0500912 *err = a_ops->write_end(o_filp, mapping, offs, data_size, replaced_size,
Akira Fujita748de672009-06-17 19:24:03 -0400913 page, fsdata);
914 page = NULL;
915
916out:
917 if (unlikely(page)) {
918 if (PageLocked(page))
919 unlock_page(page);
920 page_cache_release(page);
Peng Tao91cc2192009-08-10 23:05:28 -0400921 ext4_journal_stop(handle);
Akira Fujita748de672009-06-17 19:24:03 -0400922 }
923out2:
924 ext4_journal_stop(handle);
925
Akira Fujitaf868a482009-11-23 07:25:48 -0500926 if (err2)
927 *err = err2;
928
929 return replaced_count;
Akira Fujita748de672009-06-17 19:24:03 -0400930}
931
932/**
Akira Fujitac437b272010-03-04 00:39:24 -0500933 * mext_check_arguments - Check whether move extent can be done
Akira Fujita748de672009-06-17 19:24:03 -0400934 *
935 * @orig_inode: original inode
936 * @donor_inode: donor inode
937 * @orig_start: logical start offset in block for orig
938 * @donor_start: logical start offset in block for donor
939 * @len: the number of blocks to be moved
Akira Fujita748de672009-06-17 19:24:03 -0400940 *
941 * Check the arguments of ext4_move_extents() whether the files can be
942 * exchanged with each other.
943 * Return 0 on success, or a negative error value on failure.
944 */
945static int
946mext_check_arguments(struct inode *orig_inode,
Kazuya Mio446aaa62009-11-24 10:28:48 -0500947 struct inode *donor_inode, __u64 orig_start,
948 __u64 donor_start, __u64 *len)
Akira Fujita748de672009-06-17 19:24:03 -0400949{
Akira Fujita70d5d3d2009-09-16 14:28:22 -0400950 ext4_lblk_t orig_blocks, donor_blocks;
951 unsigned int blkbits = orig_inode->i_blkbits;
952 unsigned int blocksize = 1 << blkbits;
953
Akira Fujita4a585792009-12-06 23:38:31 -0500954 if (donor_inode->i_mode & (S_ISUID|S_ISGID)) {
955 ext4_debug("ext4 move extent: suid or sgid is set"
956 " to donor file [ino:orig %lu, donor %lu]\n",
957 orig_inode->i_ino, donor_inode->i_ino);
958 return -EINVAL;
959 }
960
Theodore Ts'o1f5a81e2010-06-02 22:04:39 -0400961 if (IS_IMMUTABLE(donor_inode) || IS_APPEND(donor_inode))
962 return -EPERM;
963
Akira Fujita748de672009-06-17 19:24:03 -0400964 /* Ext4 move extent does not support swapfile */
965 if (IS_SWAPFILE(orig_inode) || IS_SWAPFILE(donor_inode)) {
966 ext4_debug("ext4 move extent: The argument files should "
967 "not be swapfile [ino:orig %lu, donor %lu]\n",
968 orig_inode->i_ino, donor_inode->i_ino);
969 return -EINVAL;
970 }
971
972 /* Files should be in the same ext4 FS */
973 if (orig_inode->i_sb != donor_inode->i_sb) {
974 ext4_debug("ext4 move extent: The argument files "
975 "should be in same FS [ino:orig %lu, donor %lu]\n",
976 orig_inode->i_ino, donor_inode->i_ino);
977 return -EINVAL;
978 }
979
Akira Fujita748de672009-06-17 19:24:03 -0400980 /* Ext4 move extent supports only extent based file */
Dmitry Monakhov12e9b892010-05-16 22:00:00 -0400981 if (!(ext4_test_inode_flag(orig_inode, EXT4_INODE_EXTENTS))) {
Akira Fujita748de672009-06-17 19:24:03 -0400982 ext4_debug("ext4 move extent: orig file is not extents "
983 "based file [ino:orig %lu]\n", orig_inode->i_ino);
984 return -EOPNOTSUPP;
Dmitry Monakhov12e9b892010-05-16 22:00:00 -0400985 } else if (!(ext4_test_inode_flag(donor_inode, EXT4_INODE_EXTENTS))) {
Akira Fujita748de672009-06-17 19:24:03 -0400986 ext4_debug("ext4 move extent: donor file is not extents "
987 "based file [ino:donor %lu]\n", donor_inode->i_ino);
988 return -EOPNOTSUPP;
989 }
990
991 if ((!orig_inode->i_size) || (!donor_inode->i_size)) {
992 ext4_debug("ext4 move extent: File size is 0 byte\n");
993 return -EINVAL;
994 }
995
996 /* Start offset should be same */
997 if (orig_start != donor_start) {
998 ext4_debug("ext4 move extent: orig and donor's start "
999 "offset are not same [ino:orig %lu, donor %lu]\n",
1000 orig_inode->i_ino, donor_inode->i_ino);
1001 return -EINVAL;
1002 }
1003
Lukas Czernerf17722f2011-06-06 00:05:17 -04001004 if ((orig_start >= EXT_MAX_BLOCKS) ||
1005 (donor_start >= EXT_MAX_BLOCKS) ||
1006 (*len > EXT_MAX_BLOCKS) ||
1007 (orig_start + *len >= EXT_MAX_BLOCKS)) {
Eric Sandeen0a80e982009-09-17 11:55:58 -04001008 ext4_debug("ext4 move extent: Can't handle over [%u] blocks "
Lukas Czernerf17722f2011-06-06 00:05:17 -04001009 "[ino:orig %lu, donor %lu]\n", EXT_MAX_BLOCKS,
Akira Fujita748de672009-06-17 19:24:03 -04001010 orig_inode->i_ino, donor_inode->i_ino);
1011 return -EINVAL;
1012 }
1013
1014 if (orig_inode->i_size > donor_inode->i_size) {
Akira Fujita70d5d3d2009-09-16 14:28:22 -04001015 donor_blocks = (donor_inode->i_size + blocksize - 1) >> blkbits;
1016 /* TODO: eliminate this artificial restriction */
1017 if (orig_start >= donor_blocks) {
Akira Fujita748de672009-06-17 19:24:03 -04001018 ext4_debug("ext4 move extent: orig start offset "
Akira Fujita70d5d3d2009-09-16 14:28:22 -04001019 "[%llu] should be less than donor file blocks "
1020 "[%u] [ino:orig %lu, donor %lu]\n",
1021 orig_start, donor_blocks,
Akira Fujita748de672009-06-17 19:24:03 -04001022 orig_inode->i_ino, donor_inode->i_ino);
1023 return -EINVAL;
1024 }
1025
Akira Fujita70d5d3d2009-09-16 14:28:22 -04001026 /* TODO: eliminate this artificial restriction */
1027 if (orig_start + *len > donor_blocks) {
Akira Fujita748de672009-06-17 19:24:03 -04001028 ext4_debug("ext4 move extent: End offset [%llu] should "
Akira Fujita70d5d3d2009-09-16 14:28:22 -04001029 "be less than donor file blocks [%u]."
1030 "So adjust length from %llu to %llu "
Akira Fujita748de672009-06-17 19:24:03 -04001031 "[ino:orig %lu, donor %lu]\n",
Akira Fujita70d5d3d2009-09-16 14:28:22 -04001032 orig_start + *len, donor_blocks,
1033 *len, donor_blocks - orig_start,
Akira Fujita748de672009-06-17 19:24:03 -04001034 orig_inode->i_ino, donor_inode->i_ino);
Akira Fujita70d5d3d2009-09-16 14:28:22 -04001035 *len = donor_blocks - orig_start;
Akira Fujita748de672009-06-17 19:24:03 -04001036 }
1037 } else {
Akira Fujita70d5d3d2009-09-16 14:28:22 -04001038 orig_blocks = (orig_inode->i_size + blocksize - 1) >> blkbits;
1039 if (orig_start >= orig_blocks) {
Akira Fujita748de672009-06-17 19:24:03 -04001040 ext4_debug("ext4 move extent: start offset [%llu] "
Akira Fujita70d5d3d2009-09-16 14:28:22 -04001041 "should be less than original file blocks "
1042 "[%u] [ino:orig %lu, donor %lu]\n",
1043 orig_start, orig_blocks,
Akira Fujita748de672009-06-17 19:24:03 -04001044 orig_inode->i_ino, donor_inode->i_ino);
1045 return -EINVAL;
1046 }
1047
Akira Fujita70d5d3d2009-09-16 14:28:22 -04001048 if (orig_start + *len > orig_blocks) {
Akira Fujita748de672009-06-17 19:24:03 -04001049 ext4_debug("ext4 move extent: Adjust length "
Akira Fujita70d5d3d2009-09-16 14:28:22 -04001050 "from %llu to %llu. Because it should be "
1051 "less than original file blocks "
Akira Fujita748de672009-06-17 19:24:03 -04001052 "[ino:orig %lu, donor %lu]\n",
Akira Fujita70d5d3d2009-09-16 14:28:22 -04001053 *len, orig_blocks - orig_start,
Akira Fujita748de672009-06-17 19:24:03 -04001054 orig_inode->i_ino, donor_inode->i_ino);
Akira Fujita70d5d3d2009-09-16 14:28:22 -04001055 *len = orig_blocks - orig_start;
Akira Fujita748de672009-06-17 19:24:03 -04001056 }
1057 }
1058
1059 if (!*len) {
Akira Fujita92c28152009-11-23 07:24:50 -05001060 ext4_debug("ext4 move extent: len should not be 0 "
Akira Fujita748de672009-06-17 19:24:03 -04001061 "[ino:orig %lu, donor %lu]\n", orig_inode->i_ino,
1062 donor_inode->i_ino);
1063 return -EINVAL;
1064 }
1065
1066 return 0;
1067}
1068
1069/**
1070 * mext_inode_double_lock - Lock i_mutex on both @inode1 and @inode2
1071 *
1072 * @inode1: the inode structure
1073 * @inode2: the inode structure
1074 *
Akira Fujita2147b1a2009-09-16 13:46:35 -04001075 * Lock two inodes' i_mutex by i_ino order.
1076 * If inode1 or inode2 is NULL, return -EIO. Otherwise, return 0.
Akira Fujita748de672009-06-17 19:24:03 -04001077 */
Akira Fujita2147b1a2009-09-16 13:46:35 -04001078static int
Akira Fujita748de672009-06-17 19:24:03 -04001079mext_inode_double_lock(struct inode *inode1, struct inode *inode2)
1080{
Akira Fujita2147b1a2009-09-16 13:46:35 -04001081 int ret = 0;
1082
1083 BUG_ON(inode1 == NULL && inode2 == NULL);
1084
Theodore Ts'oc398eda2010-07-27 11:56:40 -04001085 ret = mext_check_null_inode(inode1, inode2, __func__, __LINE__);
Akira Fujita2147b1a2009-09-16 13:46:35 -04001086 if (ret < 0)
1087 goto out;
1088
1089 if (inode1 == inode2) {
1090 mutex_lock(&inode1->i_mutex);
1091 goto out;
Akira Fujita748de672009-06-17 19:24:03 -04001092 }
1093
1094 if (inode1->i_ino < inode2->i_ino) {
1095 mutex_lock_nested(&inode1->i_mutex, I_MUTEX_PARENT);
1096 mutex_lock_nested(&inode2->i_mutex, I_MUTEX_CHILD);
1097 } else {
1098 mutex_lock_nested(&inode2->i_mutex, I_MUTEX_PARENT);
1099 mutex_lock_nested(&inode1->i_mutex, I_MUTEX_CHILD);
1100 }
Akira Fujita2147b1a2009-09-16 13:46:35 -04001101
1102out:
1103 return ret;
Akira Fujita748de672009-06-17 19:24:03 -04001104}
1105
1106/**
1107 * mext_inode_double_unlock - Release i_mutex on both @inode1 and @inode2
1108 *
1109 * @inode1: the inode that is released first
1110 * @inode2: the inode that is released second
1111 *
Akira Fujita2147b1a2009-09-16 13:46:35 -04001112 * If inode1 or inode2 is NULL, return -EIO. Otherwise, return 0.
Akira Fujita748de672009-06-17 19:24:03 -04001113 */
1114
Akira Fujita2147b1a2009-09-16 13:46:35 -04001115static int
Akira Fujita748de672009-06-17 19:24:03 -04001116mext_inode_double_unlock(struct inode *inode1, struct inode *inode2)
1117{
Akira Fujita2147b1a2009-09-16 13:46:35 -04001118 int ret = 0;
1119
1120 BUG_ON(inode1 == NULL && inode2 == NULL);
1121
Theodore Ts'oc398eda2010-07-27 11:56:40 -04001122 ret = mext_check_null_inode(inode1, inode2, __func__, __LINE__);
Akira Fujita2147b1a2009-09-16 13:46:35 -04001123 if (ret < 0)
1124 goto out;
1125
Akira Fujita748de672009-06-17 19:24:03 -04001126 if (inode1)
1127 mutex_unlock(&inode1->i_mutex);
1128
1129 if (inode2 && inode2 != inode1)
1130 mutex_unlock(&inode2->i_mutex);
Akira Fujita2147b1a2009-09-16 13:46:35 -04001131
1132out:
1133 return ret;
Akira Fujita748de672009-06-17 19:24:03 -04001134}
1135
1136/**
1137 * ext4_move_extents - Exchange the specified range of a file
1138 *
1139 * @o_filp: file structure of the original file
1140 * @d_filp: file structure of the donor file
1141 * @orig_start: start offset in block for orig
1142 * @donor_start: start offset in block for donor
1143 * @len: the number of blocks to be moved
1144 * @moved_len: moved block length
1145 *
1146 * This function returns 0 and moved block length is set in moved_len
1147 * if succeed, otherwise returns error value.
1148 *
1149 * Note: ext4_move_extents() proceeds the following order.
1150 * 1:ext4_move_extents() calculates the last block number of moving extent
1151 * function by the start block number (orig_start) and the number of blocks
1152 * to be moved (len) specified as arguments.
1153 * If the {orig, donor}_start points a hole, the extent's start offset
1154 * pointed by ext_cur (current extent), holecheck_path, orig_path are set
1155 * after hole behind.
1156 * 2:Continue step 3 to step 5, until the holecheck_path points to last_extent
1157 * or the ext_cur exceeds the block_end which is last logical block number.
1158 * 3:To get the length of continues area, call mext_next_extent()
1159 * specified with the ext_cur (initial value is holecheck_path) re-cursive,
1160 * until find un-continuous extent, the start logical block number exceeds
1161 * the block_end or the extent points to the last extent.
1162 * 4:Exchange the original inode data with donor inode data
1163 * from orig_page_offset to seq_end_page.
1164 * The start indexes of data are specified as arguments.
1165 * That of the original inode is orig_page_offset,
1166 * and the donor inode is also orig_page_offset
1167 * (To easily handle blocksize != pagesize case, the offset for the
1168 * donor inode is block unit).
1169 * 5:Update holecheck_path and orig_path to points a next proceeding extent,
1170 * then returns to step 2.
1171 * 6:Release holecheck_path, orig_path and set the len to moved_len
1172 * which shows the number of moved blocks.
1173 * The moved_len is useful for the command to calculate the file offset
1174 * for starting next move extent ioctl.
1175 * 7:Return 0 on success, or a negative error value on failure.
1176 */
1177int
1178ext4_move_extents(struct file *o_filp, struct file *d_filp,
1179 __u64 orig_start, __u64 donor_start, __u64 len,
1180 __u64 *moved_len)
1181{
1182 struct inode *orig_inode = o_filp->f_dentry->d_inode;
1183 struct inode *donor_inode = d_filp->f_dentry->d_inode;
1184 struct ext4_ext_path *orig_path = NULL, *holecheck_path = NULL;
1185 struct ext4_extent *ext_prev, *ext_cur, *ext_dummy;
1186 ext4_lblk_t block_start = orig_start;
1187 ext4_lblk_t block_end, seq_start, add_blocks, file_end, seq_blocks = 0;
1188 ext4_lblk_t rest_blocks;
1189 pgoff_t orig_page_offset = 0, seq_end_page;
Akira Fujita2147b1a2009-09-16 13:46:35 -04001190 int ret1, ret2, depth, last_extent = 0;
Akira Fujita748de672009-06-17 19:24:03 -04001191 int blocks_per_page = PAGE_CACHE_SIZE >> orig_inode->i_blkbits;
1192 int data_offset_in_page;
1193 int block_len_in_page;
1194 int uninit;
1195
Theodore Ts'of3ce8062009-09-28 15:58:29 -04001196 /* orig and donor should be different file */
1197 if (orig_inode->i_ino == donor_inode->i_ino) {
1198 ext4_debug("ext4 move extent: The argument files should not "
1199 "be same file [ino:orig %lu, donor %lu]\n",
1200 orig_inode->i_ino, donor_inode->i_ino);
1201 return -EINVAL;
1202 }
1203
Akira Fujita7247c0c2010-03-04 00:34:58 -05001204 /* Regular file check */
1205 if (!S_ISREG(orig_inode->i_mode) || !S_ISREG(donor_inode->i_mode)) {
1206 ext4_debug("ext4 move extent: The argument files should be "
1207 "regular file [ino:orig %lu, donor %lu]\n",
1208 orig_inode->i_ino, donor_inode->i_ino);
1209 return -EINVAL;
1210 }
1211
Akira Fujitafc04cb42009-11-23 07:24:43 -05001212 /* Protect orig and donor inodes against a truncate */
Akira Fujita2147b1a2009-09-16 13:46:35 -04001213 ret1 = mext_inode_double_lock(orig_inode, donor_inode);
1214 if (ret1 < 0)
1215 return ret1;
Akira Fujita748de672009-06-17 19:24:03 -04001216
Akira Fujitafc04cb42009-11-23 07:24:43 -05001217 /* Protect extent tree against block allocations via delalloc */
1218 double_down_write_data_sem(orig_inode, donor_inode);
Akira Fujita748de672009-06-17 19:24:03 -04001219 /* Check the filesystem environment whether move_extent can be done */
Akira Fujita2147b1a2009-09-16 13:46:35 -04001220 ret1 = mext_check_arguments(orig_inode, donor_inode, orig_start,
Kazuya Mio446aaa62009-11-24 10:28:48 -05001221 donor_start, &len);
Akira Fujita2147b1a2009-09-16 13:46:35 -04001222 if (ret1)
Akira Fujita347fa6f2009-09-16 14:25:07 -04001223 goto out;
Akira Fujita748de672009-06-17 19:24:03 -04001224
1225 file_end = (i_size_read(orig_inode) - 1) >> orig_inode->i_blkbits;
1226 block_end = block_start + len - 1;
1227 if (file_end < block_end)
1228 len -= block_end - file_end;
1229
Akira Fujita2147b1a2009-09-16 13:46:35 -04001230 ret1 = get_ext_path(orig_inode, block_start, &orig_path);
Akira Fujita347fa6f2009-09-16 14:25:07 -04001231 if (ret1)
1232 goto out;
Akira Fujita748de672009-06-17 19:24:03 -04001233
1234 /* Get path structure to check the hole */
Akira Fujita2147b1a2009-09-16 13:46:35 -04001235 ret1 = get_ext_path(orig_inode, block_start, &holecheck_path);
Akira Fujita347fa6f2009-09-16 14:25:07 -04001236 if (ret1)
Akira Fujita748de672009-06-17 19:24:03 -04001237 goto out;
1238
1239 depth = ext_depth(orig_inode);
1240 ext_cur = holecheck_path[depth].p_ext;
Akira Fujita748de672009-06-17 19:24:03 -04001241
1242 /*
Akira Fujitac40ce3c2009-09-16 14:25:39 -04001243 * Get proper starting location of block replacement if block_start was
1244 * within the hole.
Akira Fujita748de672009-06-17 19:24:03 -04001245 */
1246 if (le32_to_cpu(ext_cur->ee_block) +
1247 ext4_ext_get_actual_len(ext_cur) - 1 < block_start) {
Akira Fujitac40ce3c2009-09-16 14:25:39 -04001248 /*
1249 * The hole exists between extents or the tail of
1250 * original file.
1251 */
Akira Fujita748de672009-06-17 19:24:03 -04001252 last_extent = mext_next_extent(orig_inode,
1253 holecheck_path, &ext_cur);
1254 if (last_extent < 0) {
Akira Fujita2147b1a2009-09-16 13:46:35 -04001255 ret1 = last_extent;
Akira Fujita748de672009-06-17 19:24:03 -04001256 goto out;
1257 }
1258 last_extent = mext_next_extent(orig_inode, orig_path,
1259 &ext_dummy);
1260 if (last_extent < 0) {
Akira Fujita2147b1a2009-09-16 13:46:35 -04001261 ret1 = last_extent;
Akira Fujita748de672009-06-17 19:24:03 -04001262 goto out;
1263 }
Akira Fujitac40ce3c2009-09-16 14:25:39 -04001264 seq_start = le32_to_cpu(ext_cur->ee_block);
1265 } else if (le32_to_cpu(ext_cur->ee_block) > block_start)
1266 /* The hole exists at the beginning of original file. */
1267 seq_start = le32_to_cpu(ext_cur->ee_block);
1268 else
1269 seq_start = block_start;
Akira Fujita748de672009-06-17 19:24:03 -04001270
1271 /* No blocks within the specified range. */
1272 if (le32_to_cpu(ext_cur->ee_block) > block_end) {
1273 ext4_debug("ext4 move extent: The specified range of file "
1274 "may be the hole\n");
Akira Fujita2147b1a2009-09-16 13:46:35 -04001275 ret1 = -EINVAL;
Akira Fujita748de672009-06-17 19:24:03 -04001276 goto out;
1277 }
1278
1279 /* Adjust start blocks */
1280 add_blocks = min(le32_to_cpu(ext_cur->ee_block) +
1281 ext4_ext_get_actual_len(ext_cur), block_end + 1) -
1282 max(le32_to_cpu(ext_cur->ee_block), block_start);
1283
1284 while (!last_extent && le32_to_cpu(ext_cur->ee_block) <= block_end) {
1285 seq_blocks += add_blocks;
1286
1287 /* Adjust tail blocks */
1288 if (seq_start + seq_blocks - 1 > block_end)
1289 seq_blocks = block_end - seq_start + 1;
1290
1291 ext_prev = ext_cur;
1292 last_extent = mext_next_extent(orig_inode, holecheck_path,
1293 &ext_cur);
1294 if (last_extent < 0) {
Akira Fujita2147b1a2009-09-16 13:46:35 -04001295 ret1 = last_extent;
Akira Fujita748de672009-06-17 19:24:03 -04001296 break;
1297 }
1298 add_blocks = ext4_ext_get_actual_len(ext_cur);
1299
1300 /*
1301 * Extend the length of contiguous block (seq_blocks)
1302 * if extents are contiguous.
1303 */
1304 if (ext4_can_extents_be_merged(orig_inode,
1305 ext_prev, ext_cur) &&
1306 block_end >= le32_to_cpu(ext_cur->ee_block) &&
1307 !last_extent)
1308 continue;
1309
1310 /* Is original extent is uninitialized */
1311 uninit = ext4_ext_is_uninitialized(ext_prev);
1312
1313 data_offset_in_page = seq_start % blocks_per_page;
1314
1315 /*
1316 * Calculate data blocks count that should be swapped
1317 * at the first page.
1318 */
1319 if (data_offset_in_page + seq_blocks > blocks_per_page) {
1320 /* Swapped blocks are across pages */
1321 block_len_in_page =
1322 blocks_per_page - data_offset_in_page;
1323 } else {
1324 /* Swapped blocks are in a page */
1325 block_len_in_page = seq_blocks;
1326 }
1327
1328 orig_page_offset = seq_start >>
1329 (PAGE_CACHE_SHIFT - orig_inode->i_blkbits);
1330 seq_end_page = (seq_start + seq_blocks - 1) >>
1331 (PAGE_CACHE_SHIFT - orig_inode->i_blkbits);
1332 seq_start = le32_to_cpu(ext_cur->ee_block);
1333 rest_blocks = seq_blocks;
1334
Akira Fujitafc04cb42009-11-23 07:24:43 -05001335 /*
1336 * Up semaphore to avoid following problems:
1337 * a. transaction deadlock among ext4_journal_start,
1338 * ->write_begin via pagefault, and jbd2_journal_commit
1339 * b. racing with ->readpage, ->write_begin, and ext4_get_block
1340 * in move_extent_per_page
1341 */
1342 double_up_write_data_sem(orig_inode, donor_inode);
Akira Fujita748de672009-06-17 19:24:03 -04001343
1344 while (orig_page_offset <= seq_end_page) {
1345
1346 /* Swap original branches with new branches */
Akira Fujitaf868a482009-11-23 07:25:48 -05001347 block_len_in_page = move_extent_per_page(
1348 o_filp, donor_inode,
Akira Fujita748de672009-06-17 19:24:03 -04001349 orig_page_offset,
1350 data_offset_in_page,
Akira Fujitaf868a482009-11-23 07:25:48 -05001351 block_len_in_page, uninit,
1352 &ret1);
1353
Akira Fujita748de672009-06-17 19:24:03 -04001354 /* Count how many blocks we have exchanged */
1355 *moved_len += block_len_in_page;
Akira Fujitaf868a482009-11-23 07:25:48 -05001356 if (ret1 < 0)
Akira Fujitafc04cb42009-11-23 07:24:43 -05001357 break;
Akira Fujita2147b1a2009-09-16 13:46:35 -04001358 if (*moved_len > len) {
Theodore Ts'o24676da2010-05-16 21:00:00 -04001359 EXT4_ERROR_INODE(orig_inode,
Akira Fujita2147b1a2009-09-16 13:46:35 -04001360 "We replaced blocks too much! "
1361 "sum of replaced: %llu requested: %llu",
1362 *moved_len, len);
1363 ret1 = -EIO;
Akira Fujitafc04cb42009-11-23 07:24:43 -05001364 break;
Akira Fujita2147b1a2009-09-16 13:46:35 -04001365 }
Akira Fujita748de672009-06-17 19:24:03 -04001366
Akira Fujitaf868a482009-11-23 07:25:48 -05001367 orig_page_offset++;
Akira Fujita748de672009-06-17 19:24:03 -04001368 data_offset_in_page = 0;
1369 rest_blocks -= block_len_in_page;
1370 if (rest_blocks > blocks_per_page)
1371 block_len_in_page = blocks_per_page;
1372 else
1373 block_len_in_page = rest_blocks;
1374 }
1375
Akira Fujitafc04cb42009-11-23 07:24:43 -05001376 double_down_write_data_sem(orig_inode, donor_inode);
1377 if (ret1 < 0)
1378 break;
1379
Akira Fujita748de672009-06-17 19:24:03 -04001380 /* Decrease buffer counter */
1381 if (holecheck_path)
1382 ext4_ext_drop_refs(holecheck_path);
Akira Fujita2147b1a2009-09-16 13:46:35 -04001383 ret1 = get_ext_path(orig_inode, seq_start, &holecheck_path);
Akira Fujita347fa6f2009-09-16 14:25:07 -04001384 if (ret1)
Akira Fujita748de672009-06-17 19:24:03 -04001385 break;
1386 depth = holecheck_path->p_depth;
1387
1388 /* Decrease buffer counter */
1389 if (orig_path)
1390 ext4_ext_drop_refs(orig_path);
Akira Fujita2147b1a2009-09-16 13:46:35 -04001391 ret1 = get_ext_path(orig_inode, seq_start, &orig_path);
Akira Fujita347fa6f2009-09-16 14:25:07 -04001392 if (ret1)
Akira Fujita748de672009-06-17 19:24:03 -04001393 break;
1394
1395 ext_cur = holecheck_path[depth].p_ext;
1396 add_blocks = ext4_ext_get_actual_len(ext_cur);
1397 seq_blocks = 0;
1398
1399 }
1400out:
Akira Fujita94d7c162009-11-24 10:19:57 -05001401 if (*moved_len) {
1402 ext4_discard_preallocations(orig_inode);
1403 ext4_discard_preallocations(donor_inode);
1404 }
1405
Akira Fujita748de672009-06-17 19:24:03 -04001406 if (orig_path) {
1407 ext4_ext_drop_refs(orig_path);
1408 kfree(orig_path);
1409 }
1410 if (holecheck_path) {
1411 ext4_ext_drop_refs(holecheck_path);
1412 kfree(holecheck_path);
1413 }
Akira Fujitafc04cb42009-11-23 07:24:43 -05001414 double_up_write_data_sem(orig_inode, donor_inode);
Akira Fujita2147b1a2009-09-16 13:46:35 -04001415 ret2 = mext_inode_double_unlock(orig_inode, donor_inode);
Akira Fujita748de672009-06-17 19:24:03 -04001416
Akira Fujita2147b1a2009-09-16 13:46:35 -04001417 if (ret1)
1418 return ret1;
1419 else if (ret2)
1420 return ret2;
Akira Fujita748de672009-06-17 19:24:03 -04001421
Akira Fujita748de672009-06-17 19:24:03 -04001422 return 0;
1423}