blob: ccce8a7e94edc9ca2d23b76e94bd45339869970d [file] [log] [blame]
Alex Tomasa86c6182006-10-11 01:21:03 -07001/*
2 * Copyright (c) 2003-2006, Cluster File Systems, Inc, info@clusterfs.com
3 * Written by Alex Tomas <alex@clusterfs.com>
4 *
5 * Architecture independence:
6 * Copyright (c) 2005, Bull S.A.
7 * Written by Pierre Peiffer <pierre.peiffer@bull.net>
8 *
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License version 2 as
11 * published by the Free Software Foundation.
12 *
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
17 *
18 * You should have received a copy of the GNU General Public Licens
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-
21 */
22
23/*
24 * Extents support for EXT4
25 *
26 * TODO:
27 * - ext4*_error() should be used in some situations
28 * - analyze all BUG()/BUG_ON(), use -EIO where appropriate
29 * - smart tree reduction
30 */
31
32#include <linux/module.h>
33#include <linux/fs.h>
34#include <linux/time.h>
Mingming Caocd02ff02007-10-16 18:38:25 -040035#include <linux/jbd2.h>
Alex Tomasa86c6182006-10-11 01:21:03 -070036#include <linux/highuid.h>
37#include <linux/pagemap.h>
38#include <linux/quotaops.h>
39#include <linux/string.h>
40#include <linux/slab.h>
Amit Aroraa2df2a62007-07-17 21:42:41 -040041#include <linux/falloc.h>
Alex Tomasa86c6182006-10-11 01:21:03 -070042#include <asm/uaccess.h>
Eric Sandeen6873fa02008-10-07 00:46:36 -040043#include <linux/fiemap.h>
Christoph Hellwig3dcf5452008-04-29 18:13:32 -040044#include "ext4_jbd2.h"
45#include "ext4_extents.h"
Alex Tomasa86c6182006-10-11 01:21:03 -070046
Jan Kara487caee2009-08-17 22:17:20 -040047static int ext4_ext_truncate_extend_restart(handle_t *handle,
48 struct inode *inode,
49 int needed)
Alex Tomasa86c6182006-10-11 01:21:03 -070050{
51 int err;
52
Frank Mayhar03901312009-01-07 00:06:22 -050053 if (!ext4_handle_valid(handle))
54 return 0;
Alex Tomasa86c6182006-10-11 01:21:03 -070055 if (handle->h_buffer_credits > needed)
Shen Feng9102e4f2008-07-11 19:27:31 -040056 return 0;
57 err = ext4_journal_extend(handle, needed);
Theodore Ts'o0123c932008-08-01 20:57:54 -040058 if (err <= 0)
Shen Feng9102e4f2008-07-11 19:27:31 -040059 return err;
Jan Kara487caee2009-08-17 22:17:20 -040060 err = ext4_truncate_restart_trans(handle, inode, needed);
Dmitry Monakhov0617b832010-05-17 01:00:00 -040061 if (err == 0)
62 err = -EAGAIN;
Jan Kara487caee2009-08-17 22:17:20 -040063
64 return err;
Alex Tomasa86c6182006-10-11 01:21:03 -070065}
66
67/*
68 * could return:
69 * - EROFS
70 * - ENOMEM
71 */
72static int ext4_ext_get_access(handle_t *handle, struct inode *inode,
73 struct ext4_ext_path *path)
74{
75 if (path->p_bh) {
76 /* path points to block */
77 return ext4_journal_get_write_access(handle, path->p_bh);
78 }
79 /* path points to leaf/index in inode body */
80 /* we use in-core data, no need to protect them */
81 return 0;
82}
83
84/*
85 * could return:
86 * - EROFS
87 * - ENOMEM
88 * - EIO
89 */
90static int ext4_ext_dirty(handle_t *handle, struct inode *inode,
91 struct ext4_ext_path *path)
92{
93 int err;
94 if (path->p_bh) {
95 /* path points to block */
Frank Mayhar03901312009-01-07 00:06:22 -050096 err = ext4_handle_dirty_metadata(handle, inode, path->p_bh);
Alex Tomasa86c6182006-10-11 01:21:03 -070097 } else {
98 /* path points to leaf/index in inode body */
99 err = ext4_mark_inode_dirty(handle, inode);
100 }
101 return err;
102}
103
Alex Tomasf65e6fb2006-10-11 01:21:05 -0700104static ext4_fsblk_t ext4_ext_find_goal(struct inode *inode,
Alex Tomasa86c6182006-10-11 01:21:03 -0700105 struct ext4_ext_path *path,
Aneesh Kumar K.V725d26d2008-01-28 23:58:27 -0500106 ext4_lblk_t block)
Alex Tomasa86c6182006-10-11 01:21:03 -0700107{
108 struct ext4_inode_info *ei = EXT4_I(inode);
Alex Tomasf65e6fb2006-10-11 01:21:05 -0700109 ext4_fsblk_t bg_start;
Valerie Clement74d34872008-02-15 13:43:07 -0500110 ext4_fsblk_t last_block;
Alex Tomasf65e6fb2006-10-11 01:21:05 -0700111 ext4_grpblk_t colour;
Theodore Ts'oa4912122009-03-12 12:18:34 -0400112 ext4_group_t block_group;
113 int flex_size = ext4_flex_bg_size(EXT4_SB(inode->i_sb));
Alex Tomasa86c6182006-10-11 01:21:03 -0700114 int depth;
115
116 if (path) {
117 struct ext4_extent *ex;
118 depth = path->p_depth;
119
Kazuya Mioad4fb9c2011-01-10 12:12:28 -0500120 /*
121 * Try to predict block placement assuming that we are
122 * filling in a file which will eventually be
123 * non-sparse --- i.e., in the case of libbfd writing
124 * an ELF object sections out-of-order but in a way
125 * the eventually results in a contiguous object or
126 * executable file, or some database extending a table
127 * space file. However, this is actually somewhat
128 * non-ideal if we are writing a sparse file such as
129 * qemu or KVM writing a raw image file that is going
130 * to stay fairly sparse, since it will end up
131 * fragmenting the file system's free space. Maybe we
132 * should have some hueristics or some way to allow
133 * userspace to pass a hint to file system,
134 * especiially if the latter case turns out to be
135 * common.
136 */
Avantika Mathur7e028972006-12-06 20:41:33 -0800137 ex = path[depth].p_ext;
Kazuya Mioad4fb9c2011-01-10 12:12:28 -0500138 if (ex) {
139 ext4_fsblk_t ext_pblk = ext4_ext_pblock(ex);
140 ext4_lblk_t ext_block = le32_to_cpu(ex->ee_block);
141
142 if (block > ext_block)
143 return ext_pblk + (block - ext_block);
144 else
145 return ext_pblk - (ext_block - block);
146 }
Alex Tomasa86c6182006-10-11 01:21:03 -0700147
Randy Dunlapd0d856e2006-10-11 01:21:07 -0700148 /* it looks like index is empty;
149 * try to find starting block from index itself */
Alex Tomasa86c6182006-10-11 01:21:03 -0700150 if (path[depth].p_bh)
151 return path[depth].p_bh->b_blocknr;
152 }
153
154 /* OK. use inode's group */
Theodore Ts'oa4912122009-03-12 12:18:34 -0400155 block_group = ei->i_block_group;
156 if (flex_size >= EXT4_FLEX_SIZE_DIR_ALLOC_SCHEME) {
157 /*
158 * If there are at least EXT4_FLEX_SIZE_DIR_ALLOC_SCHEME
Theodore Ts'o60e66792010-05-17 07:00:00 -0400159 * block groups per flexgroup, reserve the first block
160 * group for directories and special files. Regular
Theodore Ts'oa4912122009-03-12 12:18:34 -0400161 * files will start at the second block group. This
Theodore Ts'o60e66792010-05-17 07:00:00 -0400162 * tends to speed up directory access and improves
Theodore Ts'oa4912122009-03-12 12:18:34 -0400163 * fsck times.
164 */
165 block_group &= ~(flex_size-1);
166 if (S_ISREG(inode->i_mode))
167 block_group++;
168 }
Akinobu Mita5661bd62010-03-03 23:53:39 -0500169 bg_start = ext4_group_first_block_no(inode->i_sb, block_group);
Valerie Clement74d34872008-02-15 13:43:07 -0500170 last_block = ext4_blocks_count(EXT4_SB(inode->i_sb)->s_es) - 1;
171
Theodore Ts'oa4912122009-03-12 12:18:34 -0400172 /*
173 * If we are doing delayed allocation, we don't need take
174 * colour into account.
175 */
176 if (test_opt(inode->i_sb, DELALLOC))
177 return bg_start;
178
Valerie Clement74d34872008-02-15 13:43:07 -0500179 if (bg_start + EXT4_BLOCKS_PER_GROUP(inode->i_sb) <= last_block)
180 colour = (current->pid % 16) *
Alex Tomasa86c6182006-10-11 01:21:03 -0700181 (EXT4_BLOCKS_PER_GROUP(inode->i_sb) / 16);
Valerie Clement74d34872008-02-15 13:43:07 -0500182 else
183 colour = (current->pid % 16) * ((last_block - bg_start) / 16);
Alex Tomasa86c6182006-10-11 01:21:03 -0700184 return bg_start + colour + block;
185}
186
Aneesh Kumar K.V654b4902008-07-11 19:27:31 -0400187/*
188 * Allocation for a meta data block
189 */
Alex Tomasf65e6fb2006-10-11 01:21:05 -0700190static ext4_fsblk_t
Aneesh Kumar K.V654b4902008-07-11 19:27:31 -0400191ext4_ext_new_meta_block(handle_t *handle, struct inode *inode,
Alex Tomasa86c6182006-10-11 01:21:03 -0700192 struct ext4_ext_path *path,
193 struct ext4_extent *ex, int *err)
194{
Alex Tomasf65e6fb2006-10-11 01:21:05 -0700195 ext4_fsblk_t goal, newblock;
Alex Tomasa86c6182006-10-11 01:21:03 -0700196
197 goal = ext4_ext_find_goal(inode, path, le32_to_cpu(ex->ee_block));
Theodore Ts'o97df5d12008-12-12 12:41:28 -0500198 newblock = ext4_new_meta_blocks(handle, inode, goal, NULL, err);
Alex Tomasa86c6182006-10-11 01:21:03 -0700199 return newblock;
200}
201
Theodore Ts'o55ad63b2009-08-28 10:40:33 -0400202static inline int ext4_ext_space_block(struct inode *inode, int check)
Alex Tomasa86c6182006-10-11 01:21:03 -0700203{
204 int size;
205
206 size = (inode->i_sb->s_blocksize - sizeof(struct ext4_extent_header))
207 / sizeof(struct ext4_extent);
Theodore Ts'o55ad63b2009-08-28 10:40:33 -0400208 if (!check) {
Robert P. J. Daybbf2f9f2007-02-17 19:20:16 +0100209#ifdef AGGRESSIVE_TEST
Theodore Ts'o55ad63b2009-08-28 10:40:33 -0400210 if (size > 6)
211 size = 6;
Alex Tomasa86c6182006-10-11 01:21:03 -0700212#endif
Theodore Ts'o55ad63b2009-08-28 10:40:33 -0400213 }
Alex Tomasa86c6182006-10-11 01:21:03 -0700214 return size;
215}
216
Theodore Ts'o55ad63b2009-08-28 10:40:33 -0400217static inline int ext4_ext_space_block_idx(struct inode *inode, int check)
Alex Tomasa86c6182006-10-11 01:21:03 -0700218{
219 int size;
220
221 size = (inode->i_sb->s_blocksize - sizeof(struct ext4_extent_header))
222 / sizeof(struct ext4_extent_idx);
Theodore Ts'o55ad63b2009-08-28 10:40:33 -0400223 if (!check) {
Robert P. J. Daybbf2f9f2007-02-17 19:20:16 +0100224#ifdef AGGRESSIVE_TEST
Theodore Ts'o55ad63b2009-08-28 10:40:33 -0400225 if (size > 5)
226 size = 5;
Alex Tomasa86c6182006-10-11 01:21:03 -0700227#endif
Theodore Ts'o55ad63b2009-08-28 10:40:33 -0400228 }
Alex Tomasa86c6182006-10-11 01:21:03 -0700229 return size;
230}
231
Theodore Ts'o55ad63b2009-08-28 10:40:33 -0400232static inline int ext4_ext_space_root(struct inode *inode, int check)
Alex Tomasa86c6182006-10-11 01:21:03 -0700233{
234 int size;
235
236 size = sizeof(EXT4_I(inode)->i_data);
237 size -= sizeof(struct ext4_extent_header);
238 size /= sizeof(struct ext4_extent);
Theodore Ts'o55ad63b2009-08-28 10:40:33 -0400239 if (!check) {
Robert P. J. Daybbf2f9f2007-02-17 19:20:16 +0100240#ifdef AGGRESSIVE_TEST
Theodore Ts'o55ad63b2009-08-28 10:40:33 -0400241 if (size > 3)
242 size = 3;
Alex Tomasa86c6182006-10-11 01:21:03 -0700243#endif
Theodore Ts'o55ad63b2009-08-28 10:40:33 -0400244 }
Alex Tomasa86c6182006-10-11 01:21:03 -0700245 return size;
246}
247
Theodore Ts'o55ad63b2009-08-28 10:40:33 -0400248static inline int ext4_ext_space_root_idx(struct inode *inode, int check)
Alex Tomasa86c6182006-10-11 01:21:03 -0700249{
250 int size;
251
252 size = sizeof(EXT4_I(inode)->i_data);
253 size -= sizeof(struct ext4_extent_header);
254 size /= sizeof(struct ext4_extent_idx);
Theodore Ts'o55ad63b2009-08-28 10:40:33 -0400255 if (!check) {
Robert P. J. Daybbf2f9f2007-02-17 19:20:16 +0100256#ifdef AGGRESSIVE_TEST
Theodore Ts'o55ad63b2009-08-28 10:40:33 -0400257 if (size > 4)
258 size = 4;
Alex Tomasa86c6182006-10-11 01:21:03 -0700259#endif
Theodore Ts'o55ad63b2009-08-28 10:40:33 -0400260 }
Alex Tomasa86c6182006-10-11 01:21:03 -0700261 return size;
262}
263
Mingming Caod2a17632008-07-14 17:52:37 -0400264/*
265 * Calculate the number of metadata blocks needed
266 * to allocate @blocks
267 * Worse case is one block per extent
268 */
Theodore Ts'o01f49d02011-01-10 12:13:03 -0500269int ext4_ext_calc_metadata_amount(struct inode *inode, ext4_lblk_t lblock)
Mingming Caod2a17632008-07-14 17:52:37 -0400270{
Theodore Ts'o9d0be502010-01-01 02:41:30 -0500271 struct ext4_inode_info *ei = EXT4_I(inode);
272 int idxs, num = 0;
Mingming Caod2a17632008-07-14 17:52:37 -0400273
Theodore Ts'o9d0be502010-01-01 02:41:30 -0500274 idxs = ((inode->i_sb->s_blocksize - sizeof(struct ext4_extent_header))
275 / sizeof(struct ext4_extent_idx));
Mingming Caod2a17632008-07-14 17:52:37 -0400276
277 /*
Theodore Ts'o9d0be502010-01-01 02:41:30 -0500278 * If the new delayed allocation block is contiguous with the
279 * previous da block, it can share index blocks with the
280 * previous block, so we only need to allocate a new index
281 * block every idxs leaf blocks. At ldxs**2 blocks, we need
282 * an additional index block, and at ldxs**3 blocks, yet
283 * another index blocks.
Mingming Caod2a17632008-07-14 17:52:37 -0400284 */
Theodore Ts'o9d0be502010-01-01 02:41:30 -0500285 if (ei->i_da_metadata_calc_len &&
286 ei->i_da_metadata_calc_last_lblock+1 == lblock) {
287 if ((ei->i_da_metadata_calc_len % idxs) == 0)
288 num++;
289 if ((ei->i_da_metadata_calc_len % (idxs*idxs)) == 0)
290 num++;
291 if ((ei->i_da_metadata_calc_len % (idxs*idxs*idxs)) == 0) {
292 num++;
293 ei->i_da_metadata_calc_len = 0;
294 } else
295 ei->i_da_metadata_calc_len++;
296 ei->i_da_metadata_calc_last_lblock++;
297 return num;
298 }
Mingming Caod2a17632008-07-14 17:52:37 -0400299
Theodore Ts'o9d0be502010-01-01 02:41:30 -0500300 /*
301 * In the worst case we need a new set of index blocks at
302 * every level of the inode's extent tree.
303 */
304 ei->i_da_metadata_calc_len = 1;
305 ei->i_da_metadata_calc_last_lblock = lblock;
306 return ext_depth(inode) + 1;
Mingming Caod2a17632008-07-14 17:52:37 -0400307}
308
Alex Tomasc29c0ae2007-07-18 09:19:09 -0400309static int
310ext4_ext_max_entries(struct inode *inode, int depth)
311{
312 int max;
313
314 if (depth == ext_depth(inode)) {
315 if (depth == 0)
Theodore Ts'o55ad63b2009-08-28 10:40:33 -0400316 max = ext4_ext_space_root(inode, 1);
Alex Tomasc29c0ae2007-07-18 09:19:09 -0400317 else
Theodore Ts'o55ad63b2009-08-28 10:40:33 -0400318 max = ext4_ext_space_root_idx(inode, 1);
Alex Tomasc29c0ae2007-07-18 09:19:09 -0400319 } else {
320 if (depth == 0)
Theodore Ts'o55ad63b2009-08-28 10:40:33 -0400321 max = ext4_ext_space_block(inode, 1);
Alex Tomasc29c0ae2007-07-18 09:19:09 -0400322 else
Theodore Ts'o55ad63b2009-08-28 10:40:33 -0400323 max = ext4_ext_space_block_idx(inode, 1);
Alex Tomasc29c0ae2007-07-18 09:19:09 -0400324 }
325
326 return max;
327}
328
Aneesh Kumar K.V56b19862009-03-12 09:51:20 -0400329static int ext4_valid_extent(struct inode *inode, struct ext4_extent *ext)
330{
Theodore Ts'obf89d162010-10-27 21:30:14 -0400331 ext4_fsblk_t block = ext4_ext_pblock(ext);
Aneesh Kumar K.V56b19862009-03-12 09:51:20 -0400332 int len = ext4_ext_get_actual_len(ext);
Theodore Ts'oe84a26c2009-04-22 20:52:25 -0400333
Theodore Ts'o6fd058f2009-05-17 15:38:01 -0400334 return ext4_data_block_valid(EXT4_SB(inode->i_sb), block, len);
Aneesh Kumar K.V56b19862009-03-12 09:51:20 -0400335}
336
337static int ext4_valid_extent_idx(struct inode *inode,
338 struct ext4_extent_idx *ext_idx)
339{
Theodore Ts'obf89d162010-10-27 21:30:14 -0400340 ext4_fsblk_t block = ext4_idx_pblock(ext_idx);
Theodore Ts'oe84a26c2009-04-22 20:52:25 -0400341
Theodore Ts'o6fd058f2009-05-17 15:38:01 -0400342 return ext4_data_block_valid(EXT4_SB(inode->i_sb), block, 1);
Aneesh Kumar K.V56b19862009-03-12 09:51:20 -0400343}
344
345static int ext4_valid_extent_entries(struct inode *inode,
346 struct ext4_extent_header *eh,
347 int depth)
348{
349 struct ext4_extent *ext;
350 struct ext4_extent_idx *ext_idx;
351 unsigned short entries;
352 if (eh->eh_entries == 0)
353 return 1;
354
355 entries = le16_to_cpu(eh->eh_entries);
356
357 if (depth == 0) {
358 /* leaf entries */
359 ext = EXT_FIRST_EXTENT(eh);
360 while (entries) {
361 if (!ext4_valid_extent(inode, ext))
362 return 0;
363 ext++;
364 entries--;
365 }
366 } else {
367 ext_idx = EXT_FIRST_INDEX(eh);
368 while (entries) {
369 if (!ext4_valid_extent_idx(inode, ext_idx))
370 return 0;
371 ext_idx++;
372 entries--;
373 }
374 }
375 return 1;
376}
377
Theodore Ts'oc398eda2010-07-27 11:56:40 -0400378static int __ext4_ext_check(const char *function, unsigned int line,
379 struct inode *inode, struct ext4_extent_header *eh,
380 int depth)
Alex Tomasc29c0ae2007-07-18 09:19:09 -0400381{
382 const char *error_msg;
383 int max = 0;
384
385 if (unlikely(eh->eh_magic != EXT4_EXT_MAGIC)) {
386 error_msg = "invalid magic";
387 goto corrupted;
388 }
389 if (unlikely(le16_to_cpu(eh->eh_depth) != depth)) {
390 error_msg = "unexpected eh_depth";
391 goto corrupted;
392 }
393 if (unlikely(eh->eh_max == 0)) {
394 error_msg = "invalid eh_max";
395 goto corrupted;
396 }
397 max = ext4_ext_max_entries(inode, depth);
398 if (unlikely(le16_to_cpu(eh->eh_max) > max)) {
399 error_msg = "too large eh_max";
400 goto corrupted;
401 }
402 if (unlikely(le16_to_cpu(eh->eh_entries) > le16_to_cpu(eh->eh_max))) {
403 error_msg = "invalid eh_entries";
404 goto corrupted;
405 }
Aneesh Kumar K.V56b19862009-03-12 09:51:20 -0400406 if (!ext4_valid_extent_entries(inode, eh, depth)) {
407 error_msg = "invalid extent entries";
408 goto corrupted;
409 }
Alex Tomasc29c0ae2007-07-18 09:19:09 -0400410 return 0;
411
412corrupted:
Theodore Ts'oc398eda2010-07-27 11:56:40 -0400413 ext4_error_inode(inode, function, line, 0,
Theodore Ts'o24676da2010-05-16 21:00:00 -0400414 "bad header/extent: %s - magic %x, "
Alex Tomasc29c0ae2007-07-18 09:19:09 -0400415 "entries %u, max %u(%u), depth %u(%u)",
Theodore Ts'o24676da2010-05-16 21:00:00 -0400416 error_msg, le16_to_cpu(eh->eh_magic),
Alex Tomasc29c0ae2007-07-18 09:19:09 -0400417 le16_to_cpu(eh->eh_entries), le16_to_cpu(eh->eh_max),
418 max, le16_to_cpu(eh->eh_depth), depth);
419
420 return -EIO;
421}
422
Aneesh Kumar K.V56b19862009-03-12 09:51:20 -0400423#define ext4_ext_check(inode, eh, depth) \
Theodore Ts'oc398eda2010-07-27 11:56:40 -0400424 __ext4_ext_check(__func__, __LINE__, inode, eh, depth)
Alex Tomasc29c0ae2007-07-18 09:19:09 -0400425
Aneesh Kumar K.V7a262f72009-03-27 16:39:58 -0400426int ext4_ext_check_inode(struct inode *inode)
427{
428 return ext4_ext_check(inode, ext_inode_hdr(inode), ext_depth(inode));
429}
430
Alex Tomasa86c6182006-10-11 01:21:03 -0700431#ifdef EXT_DEBUG
432static void ext4_ext_show_path(struct inode *inode, struct ext4_ext_path *path)
433{
434 int k, l = path->p_depth;
435
436 ext_debug("path:");
437 for (k = 0; k <= l; k++, path++) {
438 if (path->p_idx) {
Mingming Cao2ae02102006-10-11 01:21:11 -0700439 ext_debug(" %d->%llu", le32_to_cpu(path->p_idx->ei_block),
Theodore Ts'obf89d162010-10-27 21:30:14 -0400440 ext4_idx_pblock(path->p_idx));
Alex Tomasa86c6182006-10-11 01:21:03 -0700441 } else if (path->p_ext) {
Mingming553f9002009-09-18 13:34:55 -0400442 ext_debug(" %d:[%d]%d:%llu ",
Alex Tomasa86c6182006-10-11 01:21:03 -0700443 le32_to_cpu(path->p_ext->ee_block),
Mingming553f9002009-09-18 13:34:55 -0400444 ext4_ext_is_uninitialized(path->p_ext),
Amit Aroraa2df2a62007-07-17 21:42:41 -0400445 ext4_ext_get_actual_len(path->p_ext),
Theodore Ts'obf89d162010-10-27 21:30:14 -0400446 ext4_ext_pblock(path->p_ext));
Alex Tomasa86c6182006-10-11 01:21:03 -0700447 } else
448 ext_debug(" []");
449 }
450 ext_debug("\n");
451}
452
453static void ext4_ext_show_leaf(struct inode *inode, struct ext4_ext_path *path)
454{
455 int depth = ext_depth(inode);
456 struct ext4_extent_header *eh;
457 struct ext4_extent *ex;
458 int i;
459
460 if (!path)
461 return;
462
463 eh = path[depth].p_hdr;
464 ex = EXT_FIRST_EXTENT(eh);
465
Mingming553f9002009-09-18 13:34:55 -0400466 ext_debug("Displaying leaf extents for inode %lu\n", inode->i_ino);
467
Alex Tomasa86c6182006-10-11 01:21:03 -0700468 for (i = 0; i < le16_to_cpu(eh->eh_entries); i++, ex++) {
Mingming553f9002009-09-18 13:34:55 -0400469 ext_debug("%d:[%d]%d:%llu ", le32_to_cpu(ex->ee_block),
470 ext4_ext_is_uninitialized(ex),
Theodore Ts'obf89d162010-10-27 21:30:14 -0400471 ext4_ext_get_actual_len(ex), ext4_ext_pblock(ex));
Alex Tomasa86c6182006-10-11 01:21:03 -0700472 }
473 ext_debug("\n");
474}
475#else
Theodore Ts'oaf5bc922008-09-08 22:25:24 -0400476#define ext4_ext_show_path(inode, path)
477#define ext4_ext_show_leaf(inode, path)
Alex Tomasa86c6182006-10-11 01:21:03 -0700478#endif
479
Aneesh Kumar K.Vb35905c2008-02-25 16:54:37 -0500480void ext4_ext_drop_refs(struct ext4_ext_path *path)
Alex Tomasa86c6182006-10-11 01:21:03 -0700481{
482 int depth = path->p_depth;
483 int i;
484
485 for (i = 0; i <= depth; i++, path++)
486 if (path->p_bh) {
487 brelse(path->p_bh);
488 path->p_bh = NULL;
489 }
490}
491
492/*
Randy Dunlapd0d856e2006-10-11 01:21:07 -0700493 * ext4_ext_binsearch_idx:
494 * binary search for the closest index of the given block
Alex Tomasc29c0ae2007-07-18 09:19:09 -0400495 * the header must be checked before calling this
Alex Tomasa86c6182006-10-11 01:21:03 -0700496 */
497static void
Aneesh Kumar K.V725d26d2008-01-28 23:58:27 -0500498ext4_ext_binsearch_idx(struct inode *inode,
499 struct ext4_ext_path *path, ext4_lblk_t block)
Alex Tomasa86c6182006-10-11 01:21:03 -0700500{
501 struct ext4_extent_header *eh = path->p_hdr;
502 struct ext4_extent_idx *r, *l, *m;
503
Alex Tomasa86c6182006-10-11 01:21:03 -0700504
Eric Sandeenbba90742008-01-28 23:58:27 -0500505 ext_debug("binsearch for %u(idx): ", block);
Alex Tomasa86c6182006-10-11 01:21:03 -0700506
507 l = EXT_FIRST_INDEX(eh) + 1;
Dmitry Monakhove9f410b2007-07-18 09:09:15 -0400508 r = EXT_LAST_INDEX(eh);
Alex Tomasa86c6182006-10-11 01:21:03 -0700509 while (l <= r) {
510 m = l + (r - l) / 2;
511 if (block < le32_to_cpu(m->ei_block))
512 r = m - 1;
513 else
514 l = m + 1;
Dmitry Monakhov26d535e2007-07-18 08:33:37 -0400515 ext_debug("%p(%u):%p(%u):%p(%u) ", l, le32_to_cpu(l->ei_block),
516 m, le32_to_cpu(m->ei_block),
517 r, le32_to_cpu(r->ei_block));
Alex Tomasa86c6182006-10-11 01:21:03 -0700518 }
519
520 path->p_idx = l - 1;
Alex Tomasf65e6fb2006-10-11 01:21:05 -0700521 ext_debug(" -> %d->%lld ", le32_to_cpu(path->p_idx->ei_block),
Theodore Ts'obf89d162010-10-27 21:30:14 -0400522 ext4_idx_pblock(path->p_idx));
Alex Tomasa86c6182006-10-11 01:21:03 -0700523
524#ifdef CHECK_BINSEARCH
525 {
526 struct ext4_extent_idx *chix, *ix;
527 int k;
528
529 chix = ix = EXT_FIRST_INDEX(eh);
530 for (k = 0; k < le16_to_cpu(eh->eh_entries); k++, ix++) {
531 if (k != 0 &&
532 le32_to_cpu(ix->ei_block) <= le32_to_cpu(ix[-1].ei_block)) {
Theodore Ts'o4776004f2008-09-08 23:00:52 -0400533 printk(KERN_DEBUG "k=%d, ix=0x%p, "
534 "first=0x%p\n", k,
535 ix, EXT_FIRST_INDEX(eh));
536 printk(KERN_DEBUG "%u <= %u\n",
Alex Tomasa86c6182006-10-11 01:21:03 -0700537 le32_to_cpu(ix->ei_block),
538 le32_to_cpu(ix[-1].ei_block));
539 }
540 BUG_ON(k && le32_to_cpu(ix->ei_block)
Dave Kleikamp8c55e202007-05-24 13:04:54 -0400541 <= le32_to_cpu(ix[-1].ei_block));
Alex Tomasa86c6182006-10-11 01:21:03 -0700542 if (block < le32_to_cpu(ix->ei_block))
543 break;
544 chix = ix;
545 }
546 BUG_ON(chix != path->p_idx);
547 }
548#endif
549
550}
551
552/*
Randy Dunlapd0d856e2006-10-11 01:21:07 -0700553 * ext4_ext_binsearch:
554 * binary search for closest extent of the given block
Alex Tomasc29c0ae2007-07-18 09:19:09 -0400555 * the header must be checked before calling this
Alex Tomasa86c6182006-10-11 01:21:03 -0700556 */
557static void
Aneesh Kumar K.V725d26d2008-01-28 23:58:27 -0500558ext4_ext_binsearch(struct inode *inode,
559 struct ext4_ext_path *path, ext4_lblk_t block)
Alex Tomasa86c6182006-10-11 01:21:03 -0700560{
561 struct ext4_extent_header *eh = path->p_hdr;
562 struct ext4_extent *r, *l, *m;
563
Alex Tomasa86c6182006-10-11 01:21:03 -0700564 if (eh->eh_entries == 0) {
565 /*
Randy Dunlapd0d856e2006-10-11 01:21:07 -0700566 * this leaf is empty:
567 * we get such a leaf in split/add case
Alex Tomasa86c6182006-10-11 01:21:03 -0700568 */
569 return;
570 }
571
Eric Sandeenbba90742008-01-28 23:58:27 -0500572 ext_debug("binsearch for %u: ", block);
Alex Tomasa86c6182006-10-11 01:21:03 -0700573
574 l = EXT_FIRST_EXTENT(eh) + 1;
Dmitry Monakhove9f410b2007-07-18 09:09:15 -0400575 r = EXT_LAST_EXTENT(eh);
Alex Tomasa86c6182006-10-11 01:21:03 -0700576
577 while (l <= r) {
578 m = l + (r - l) / 2;
579 if (block < le32_to_cpu(m->ee_block))
580 r = m - 1;
581 else
582 l = m + 1;
Dmitry Monakhov26d535e2007-07-18 08:33:37 -0400583 ext_debug("%p(%u):%p(%u):%p(%u) ", l, le32_to_cpu(l->ee_block),
584 m, le32_to_cpu(m->ee_block),
585 r, le32_to_cpu(r->ee_block));
Alex Tomasa86c6182006-10-11 01:21:03 -0700586 }
587
588 path->p_ext = l - 1;
Mingming553f9002009-09-18 13:34:55 -0400589 ext_debug(" -> %d:%llu:[%d]%d ",
Dave Kleikamp8c55e202007-05-24 13:04:54 -0400590 le32_to_cpu(path->p_ext->ee_block),
Theodore Ts'obf89d162010-10-27 21:30:14 -0400591 ext4_ext_pblock(path->p_ext),
Mingming553f9002009-09-18 13:34:55 -0400592 ext4_ext_is_uninitialized(path->p_ext),
Amit Aroraa2df2a62007-07-17 21:42:41 -0400593 ext4_ext_get_actual_len(path->p_ext));
Alex Tomasa86c6182006-10-11 01:21:03 -0700594
595#ifdef CHECK_BINSEARCH
596 {
597 struct ext4_extent *chex, *ex;
598 int k;
599
600 chex = ex = EXT_FIRST_EXTENT(eh);
601 for (k = 0; k < le16_to_cpu(eh->eh_entries); k++, ex++) {
602 BUG_ON(k && le32_to_cpu(ex->ee_block)
Dave Kleikamp8c55e202007-05-24 13:04:54 -0400603 <= le32_to_cpu(ex[-1].ee_block));
Alex Tomasa86c6182006-10-11 01:21:03 -0700604 if (block < le32_to_cpu(ex->ee_block))
605 break;
606 chex = ex;
607 }
608 BUG_ON(chex != path->p_ext);
609 }
610#endif
611
612}
613
614int ext4_ext_tree_init(handle_t *handle, struct inode *inode)
615{
616 struct ext4_extent_header *eh;
617
618 eh = ext_inode_hdr(inode);
619 eh->eh_depth = 0;
620 eh->eh_entries = 0;
621 eh->eh_magic = EXT4_EXT_MAGIC;
Theodore Ts'o55ad63b2009-08-28 10:40:33 -0400622 eh->eh_max = cpu_to_le16(ext4_ext_space_root(inode, 0));
Alex Tomasa86c6182006-10-11 01:21:03 -0700623 ext4_mark_inode_dirty(handle, inode);
624 ext4_ext_invalidate_cache(inode);
625 return 0;
626}
627
628struct ext4_ext_path *
Aneesh Kumar K.V725d26d2008-01-28 23:58:27 -0500629ext4_ext_find_extent(struct inode *inode, ext4_lblk_t block,
630 struct ext4_ext_path *path)
Alex Tomasa86c6182006-10-11 01:21:03 -0700631{
632 struct ext4_extent_header *eh;
633 struct buffer_head *bh;
634 short int depth, i, ppos = 0, alloc = 0;
635
636 eh = ext_inode_hdr(inode);
Alex Tomasc29c0ae2007-07-18 09:19:09 -0400637 depth = ext_depth(inode);
Alex Tomasa86c6182006-10-11 01:21:03 -0700638
639 /* account possible depth increase */
640 if (!path) {
Avantika Mathur5d4958f2006-12-06 20:41:35 -0800641 path = kzalloc(sizeof(struct ext4_ext_path) * (depth + 2),
Alex Tomasa86c6182006-10-11 01:21:03 -0700642 GFP_NOFS);
643 if (!path)
644 return ERR_PTR(-ENOMEM);
645 alloc = 1;
646 }
Alex Tomasa86c6182006-10-11 01:21:03 -0700647 path[0].p_hdr = eh;
Shen Feng1973adc2008-07-11 19:27:31 -0400648 path[0].p_bh = NULL;
Alex Tomasa86c6182006-10-11 01:21:03 -0700649
Alex Tomasc29c0ae2007-07-18 09:19:09 -0400650 i = depth;
Alex Tomasa86c6182006-10-11 01:21:03 -0700651 /* walk through the tree */
652 while (i) {
Aneesh Kumar K.V7a262f72009-03-27 16:39:58 -0400653 int need_to_validate = 0;
654
Alex Tomasa86c6182006-10-11 01:21:03 -0700655 ext_debug("depth %d: num %d, max %d\n",
656 ppos, le16_to_cpu(eh->eh_entries), le16_to_cpu(eh->eh_max));
Alex Tomasc29c0ae2007-07-18 09:19:09 -0400657
Alex Tomasa86c6182006-10-11 01:21:03 -0700658 ext4_ext_binsearch_idx(inode, path + ppos, block);
Theodore Ts'obf89d162010-10-27 21:30:14 -0400659 path[ppos].p_block = ext4_idx_pblock(path[ppos].p_idx);
Alex Tomasa86c6182006-10-11 01:21:03 -0700660 path[ppos].p_depth = i;
661 path[ppos].p_ext = NULL;
662
Aneesh Kumar K.V7a262f72009-03-27 16:39:58 -0400663 bh = sb_getblk(inode->i_sb, path[ppos].p_block);
664 if (unlikely(!bh))
Alex Tomasa86c6182006-10-11 01:21:03 -0700665 goto err;
Aneesh Kumar K.V7a262f72009-03-27 16:39:58 -0400666 if (!bh_uptodate_or_lock(bh)) {
667 if (bh_submit_read(bh) < 0) {
668 put_bh(bh);
669 goto err;
670 }
671 /* validate the extent entries */
672 need_to_validate = 1;
673 }
Alex Tomasa86c6182006-10-11 01:21:03 -0700674 eh = ext_block_hdr(bh);
675 ppos++;
Frank Mayhar273df552010-03-02 11:46:09 -0500676 if (unlikely(ppos > depth)) {
677 put_bh(bh);
678 EXT4_ERROR_INODE(inode,
679 "ppos %d > depth %d", ppos, depth);
680 goto err;
681 }
Alex Tomasa86c6182006-10-11 01:21:03 -0700682 path[ppos].p_bh = bh;
683 path[ppos].p_hdr = eh;
684 i--;
685
Aneesh Kumar K.V7a262f72009-03-27 16:39:58 -0400686 if (need_to_validate && ext4_ext_check(inode, eh, i))
Alex Tomasa86c6182006-10-11 01:21:03 -0700687 goto err;
688 }
689
690 path[ppos].p_depth = i;
Alex Tomasa86c6182006-10-11 01:21:03 -0700691 path[ppos].p_ext = NULL;
692 path[ppos].p_idx = NULL;
693
Alex Tomasa86c6182006-10-11 01:21:03 -0700694 /* find extent */
695 ext4_ext_binsearch(inode, path + ppos, block);
Shen Feng1973adc2008-07-11 19:27:31 -0400696 /* if not an empty leaf */
697 if (path[ppos].p_ext)
Theodore Ts'obf89d162010-10-27 21:30:14 -0400698 path[ppos].p_block = ext4_ext_pblock(path[ppos].p_ext);
Alex Tomasa86c6182006-10-11 01:21:03 -0700699
700 ext4_ext_show_path(inode, path);
701
702 return path;
703
704err:
705 ext4_ext_drop_refs(path);
706 if (alloc)
707 kfree(path);
708 return ERR_PTR(-EIO);
709}
710
711/*
Randy Dunlapd0d856e2006-10-11 01:21:07 -0700712 * ext4_ext_insert_index:
713 * insert new index [@logical;@ptr] into the block at @curp;
714 * check where to insert: before @curp or after @curp
Alex Tomasa86c6182006-10-11 01:21:03 -0700715 */
Theodore Ts'o1f109d52010-10-27 21:30:14 -0400716static int ext4_ext_insert_index(handle_t *handle, struct inode *inode,
717 struct ext4_ext_path *curp,
718 int logical, ext4_fsblk_t ptr)
Alex Tomasa86c6182006-10-11 01:21:03 -0700719{
720 struct ext4_extent_idx *ix;
721 int len, err;
722
Avantika Mathur7e028972006-12-06 20:41:33 -0800723 err = ext4_ext_get_access(handle, inode, curp);
724 if (err)
Alex Tomasa86c6182006-10-11 01:21:03 -0700725 return err;
726
Frank Mayhar273df552010-03-02 11:46:09 -0500727 if (unlikely(logical == le32_to_cpu(curp->p_idx->ei_block))) {
728 EXT4_ERROR_INODE(inode,
729 "logical %d == ei_block %d!",
730 logical, le32_to_cpu(curp->p_idx->ei_block));
731 return -EIO;
732 }
Alex Tomasa86c6182006-10-11 01:21:03 -0700733 len = EXT_MAX_INDEX(curp->p_hdr) - curp->p_idx;
734 if (logical > le32_to_cpu(curp->p_idx->ei_block)) {
735 /* insert after */
736 if (curp->p_idx != EXT_LAST_INDEX(curp->p_hdr)) {
737 len = (len - 1) * sizeof(struct ext4_extent_idx);
738 len = len < 0 ? 0 : len;
Dmitry Monakhov26d535e2007-07-18 08:33:37 -0400739 ext_debug("insert new index %d after: %llu. "
Alex Tomasa86c6182006-10-11 01:21:03 -0700740 "move %d from 0x%p to 0x%p\n",
741 logical, ptr, len,
742 (curp->p_idx + 1), (curp->p_idx + 2));
743 memmove(curp->p_idx + 2, curp->p_idx + 1, len);
744 }
745 ix = curp->p_idx + 1;
746 } else {
747 /* insert before */
748 len = len * sizeof(struct ext4_extent_idx);
749 len = len < 0 ? 0 : len;
Dmitry Monakhov26d535e2007-07-18 08:33:37 -0400750 ext_debug("insert new index %d before: %llu. "
Alex Tomasa86c6182006-10-11 01:21:03 -0700751 "move %d from 0x%p to 0x%p\n",
752 logical, ptr, len,
753 curp->p_idx, (curp->p_idx + 1));
754 memmove(curp->p_idx + 1, curp->p_idx, len);
755 ix = curp->p_idx;
756 }
757
758 ix->ei_block = cpu_to_le32(logical);
Alex Tomasf65e6fb2006-10-11 01:21:05 -0700759 ext4_idx_store_pblock(ix, ptr);
Marcin Slusarze8546d02008-04-17 10:38:59 -0400760 le16_add_cpu(&curp->p_hdr->eh_entries, 1);
Alex Tomasa86c6182006-10-11 01:21:03 -0700761
Frank Mayhar273df552010-03-02 11:46:09 -0500762 if (unlikely(le16_to_cpu(curp->p_hdr->eh_entries)
763 > le16_to_cpu(curp->p_hdr->eh_max))) {
764 EXT4_ERROR_INODE(inode,
765 "logical %d == ei_block %d!",
766 logical, le32_to_cpu(curp->p_idx->ei_block));
767 return -EIO;
768 }
769 if (unlikely(ix > EXT_LAST_INDEX(curp->p_hdr))) {
770 EXT4_ERROR_INODE(inode, "ix > EXT_LAST_INDEX!");
771 return -EIO;
772 }
Alex Tomasa86c6182006-10-11 01:21:03 -0700773
774 err = ext4_ext_dirty(handle, inode, curp);
775 ext4_std_error(inode->i_sb, err);
776
777 return err;
778}
779
780/*
Randy Dunlapd0d856e2006-10-11 01:21:07 -0700781 * ext4_ext_split:
782 * inserts new subtree into the path, using free index entry
783 * at depth @at:
784 * - allocates all needed blocks (new leaf and all intermediate index blocks)
785 * - makes decision where to split
786 * - moves remaining extents and index entries (right to the split point)
787 * into the newly allocated blocks
788 * - initializes subtree
Alex Tomasa86c6182006-10-11 01:21:03 -0700789 */
790static int ext4_ext_split(handle_t *handle, struct inode *inode,
791 struct ext4_ext_path *path,
792 struct ext4_extent *newext, int at)
793{
794 struct buffer_head *bh = NULL;
795 int depth = ext_depth(inode);
796 struct ext4_extent_header *neh;
797 struct ext4_extent_idx *fidx;
798 struct ext4_extent *ex;
799 int i = at, k, m, a;
Alex Tomasf65e6fb2006-10-11 01:21:05 -0700800 ext4_fsblk_t newblock, oldblock;
Alex Tomasa86c6182006-10-11 01:21:03 -0700801 __le32 border;
Alex Tomasf65e6fb2006-10-11 01:21:05 -0700802 ext4_fsblk_t *ablocks = NULL; /* array of allocated blocks */
Alex Tomasa86c6182006-10-11 01:21:03 -0700803 int err = 0;
804
805 /* make decision: where to split? */
Randy Dunlapd0d856e2006-10-11 01:21:07 -0700806 /* FIXME: now decision is simplest: at current extent */
Alex Tomasa86c6182006-10-11 01:21:03 -0700807
Randy Dunlapd0d856e2006-10-11 01:21:07 -0700808 /* if current leaf will be split, then we should use
Alex Tomasa86c6182006-10-11 01:21:03 -0700809 * border from split point */
Frank Mayhar273df552010-03-02 11:46:09 -0500810 if (unlikely(path[depth].p_ext > EXT_MAX_EXTENT(path[depth].p_hdr))) {
811 EXT4_ERROR_INODE(inode, "p_ext > EXT_MAX_EXTENT!");
812 return -EIO;
813 }
Alex Tomasa86c6182006-10-11 01:21:03 -0700814 if (path[depth].p_ext != EXT_MAX_EXTENT(path[depth].p_hdr)) {
815 border = path[depth].p_ext[1].ee_block;
Randy Dunlapd0d856e2006-10-11 01:21:07 -0700816 ext_debug("leaf will be split."
Alex Tomasa86c6182006-10-11 01:21:03 -0700817 " next leaf starts at %d\n",
Dave Kleikamp8c55e202007-05-24 13:04:54 -0400818 le32_to_cpu(border));
Alex Tomasa86c6182006-10-11 01:21:03 -0700819 } else {
820 border = newext->ee_block;
821 ext_debug("leaf will be added."
822 " next leaf starts at %d\n",
Dave Kleikamp8c55e202007-05-24 13:04:54 -0400823 le32_to_cpu(border));
Alex Tomasa86c6182006-10-11 01:21:03 -0700824 }
825
826 /*
Randy Dunlapd0d856e2006-10-11 01:21:07 -0700827 * If error occurs, then we break processing
828 * and mark filesystem read-only. index won't
Alex Tomasa86c6182006-10-11 01:21:03 -0700829 * be inserted and tree will be in consistent
Randy Dunlapd0d856e2006-10-11 01:21:07 -0700830 * state. Next mount will repair buffers too.
Alex Tomasa86c6182006-10-11 01:21:03 -0700831 */
832
833 /*
Randy Dunlapd0d856e2006-10-11 01:21:07 -0700834 * Get array to track all allocated blocks.
835 * We need this to handle errors and free blocks
836 * upon them.
Alex Tomasa86c6182006-10-11 01:21:03 -0700837 */
Avantika Mathur5d4958f2006-12-06 20:41:35 -0800838 ablocks = kzalloc(sizeof(ext4_fsblk_t) * depth, GFP_NOFS);
Alex Tomasa86c6182006-10-11 01:21:03 -0700839 if (!ablocks)
840 return -ENOMEM;
Alex Tomasa86c6182006-10-11 01:21:03 -0700841
842 /* allocate all needed blocks */
843 ext_debug("allocate %d blocks for indexes/leaf\n", depth - at);
844 for (a = 0; a < depth - at; a++) {
Aneesh Kumar K.V654b4902008-07-11 19:27:31 -0400845 newblock = ext4_ext_new_meta_block(handle, inode, path,
846 newext, &err);
Alex Tomasa86c6182006-10-11 01:21:03 -0700847 if (newblock == 0)
848 goto cleanup;
849 ablocks[a] = newblock;
850 }
851
852 /* initialize new leaf */
853 newblock = ablocks[--a];
Frank Mayhar273df552010-03-02 11:46:09 -0500854 if (unlikely(newblock == 0)) {
855 EXT4_ERROR_INODE(inode, "newblock == 0!");
856 err = -EIO;
857 goto cleanup;
858 }
Alex Tomasa86c6182006-10-11 01:21:03 -0700859 bh = sb_getblk(inode->i_sb, newblock);
860 if (!bh) {
861 err = -EIO;
862 goto cleanup;
863 }
864 lock_buffer(bh);
865
Avantika Mathur7e028972006-12-06 20:41:33 -0800866 err = ext4_journal_get_create_access(handle, bh);
867 if (err)
Alex Tomasa86c6182006-10-11 01:21:03 -0700868 goto cleanup;
869
870 neh = ext_block_hdr(bh);
871 neh->eh_entries = 0;
Theodore Ts'o55ad63b2009-08-28 10:40:33 -0400872 neh->eh_max = cpu_to_le16(ext4_ext_space_block(inode, 0));
Alex Tomasa86c6182006-10-11 01:21:03 -0700873 neh->eh_magic = EXT4_EXT_MAGIC;
874 neh->eh_depth = 0;
875 ex = EXT_FIRST_EXTENT(neh);
876
Randy Dunlapd0d856e2006-10-11 01:21:07 -0700877 /* move remainder of path[depth] to the new leaf */
Frank Mayhar273df552010-03-02 11:46:09 -0500878 if (unlikely(path[depth].p_hdr->eh_entries !=
879 path[depth].p_hdr->eh_max)) {
880 EXT4_ERROR_INODE(inode, "eh_entries %d != eh_max %d!",
881 path[depth].p_hdr->eh_entries,
882 path[depth].p_hdr->eh_max);
883 err = -EIO;
884 goto cleanup;
885 }
Alex Tomasa86c6182006-10-11 01:21:03 -0700886 /* start copy from next extent */
887 /* TODO: we could do it by single memmove */
888 m = 0;
889 path[depth].p_ext++;
890 while (path[depth].p_ext <=
891 EXT_MAX_EXTENT(path[depth].p_hdr)) {
Mingming553f9002009-09-18 13:34:55 -0400892 ext_debug("move %d:%llu:[%d]%d in new leaf %llu\n",
Dave Kleikamp8c55e202007-05-24 13:04:54 -0400893 le32_to_cpu(path[depth].p_ext->ee_block),
Theodore Ts'obf89d162010-10-27 21:30:14 -0400894 ext4_ext_pblock(path[depth].p_ext),
Mingming553f9002009-09-18 13:34:55 -0400895 ext4_ext_is_uninitialized(path[depth].p_ext),
Amit Aroraa2df2a62007-07-17 21:42:41 -0400896 ext4_ext_get_actual_len(path[depth].p_ext),
Alex Tomasa86c6182006-10-11 01:21:03 -0700897 newblock);
898 /*memmove(ex++, path[depth].p_ext++,
899 sizeof(struct ext4_extent));
900 neh->eh_entries++;*/
901 path[depth].p_ext++;
902 m++;
903 }
904 if (m) {
905 memmove(ex, path[depth].p_ext-m, sizeof(struct ext4_extent)*m);
Marcin Slusarze8546d02008-04-17 10:38:59 -0400906 le16_add_cpu(&neh->eh_entries, m);
Alex Tomasa86c6182006-10-11 01:21:03 -0700907 }
908
909 set_buffer_uptodate(bh);
910 unlock_buffer(bh);
911
Frank Mayhar03901312009-01-07 00:06:22 -0500912 err = ext4_handle_dirty_metadata(handle, inode, bh);
Avantika Mathur7e028972006-12-06 20:41:33 -0800913 if (err)
Alex Tomasa86c6182006-10-11 01:21:03 -0700914 goto cleanup;
915 brelse(bh);
916 bh = NULL;
917
918 /* correct old leaf */
919 if (m) {
Avantika Mathur7e028972006-12-06 20:41:33 -0800920 err = ext4_ext_get_access(handle, inode, path + depth);
921 if (err)
Alex Tomasa86c6182006-10-11 01:21:03 -0700922 goto cleanup;
Marcin Slusarze8546d02008-04-17 10:38:59 -0400923 le16_add_cpu(&path[depth].p_hdr->eh_entries, -m);
Avantika Mathur7e028972006-12-06 20:41:33 -0800924 err = ext4_ext_dirty(handle, inode, path + depth);
925 if (err)
Alex Tomasa86c6182006-10-11 01:21:03 -0700926 goto cleanup;
927
928 }
929
930 /* create intermediate indexes */
931 k = depth - at - 1;
Frank Mayhar273df552010-03-02 11:46:09 -0500932 if (unlikely(k < 0)) {
933 EXT4_ERROR_INODE(inode, "k %d < 0!", k);
934 err = -EIO;
935 goto cleanup;
936 }
Alex Tomasa86c6182006-10-11 01:21:03 -0700937 if (k)
938 ext_debug("create %d intermediate indices\n", k);
939 /* insert new index into current index block */
940 /* current depth stored in i var */
941 i = depth - 1;
942 while (k--) {
943 oldblock = newblock;
944 newblock = ablocks[--a];
Eric Sandeenbba90742008-01-28 23:58:27 -0500945 bh = sb_getblk(inode->i_sb, newblock);
Alex Tomasa86c6182006-10-11 01:21:03 -0700946 if (!bh) {
947 err = -EIO;
948 goto cleanup;
949 }
950 lock_buffer(bh);
951
Avantika Mathur7e028972006-12-06 20:41:33 -0800952 err = ext4_journal_get_create_access(handle, bh);
953 if (err)
Alex Tomasa86c6182006-10-11 01:21:03 -0700954 goto cleanup;
955
956 neh = ext_block_hdr(bh);
957 neh->eh_entries = cpu_to_le16(1);
958 neh->eh_magic = EXT4_EXT_MAGIC;
Theodore Ts'o55ad63b2009-08-28 10:40:33 -0400959 neh->eh_max = cpu_to_le16(ext4_ext_space_block_idx(inode, 0));
Alex Tomasa86c6182006-10-11 01:21:03 -0700960 neh->eh_depth = cpu_to_le16(depth - i);
961 fidx = EXT_FIRST_INDEX(neh);
962 fidx->ei_block = border;
Alex Tomasf65e6fb2006-10-11 01:21:05 -0700963 ext4_idx_store_pblock(fidx, oldblock);
Alex Tomasa86c6182006-10-11 01:21:03 -0700964
Eric Sandeenbba90742008-01-28 23:58:27 -0500965 ext_debug("int.index at %d (block %llu): %u -> %llu\n",
966 i, newblock, le32_to_cpu(border), oldblock);
Alex Tomasa86c6182006-10-11 01:21:03 -0700967 /* copy indexes */
968 m = 0;
969 path[i].p_idx++;
970
971 ext_debug("cur 0x%p, last 0x%p\n", path[i].p_idx,
972 EXT_MAX_INDEX(path[i].p_hdr));
Frank Mayhar273df552010-03-02 11:46:09 -0500973 if (unlikely(EXT_MAX_INDEX(path[i].p_hdr) !=
974 EXT_LAST_INDEX(path[i].p_hdr))) {
975 EXT4_ERROR_INODE(inode,
976 "EXT_MAX_INDEX != EXT_LAST_INDEX ee_block %d!",
977 le32_to_cpu(path[i].p_ext->ee_block));
978 err = -EIO;
979 goto cleanup;
980 }
Alex Tomasa86c6182006-10-11 01:21:03 -0700981 while (path[i].p_idx <= EXT_MAX_INDEX(path[i].p_hdr)) {
Dmitry Monakhov26d535e2007-07-18 08:33:37 -0400982 ext_debug("%d: move %d:%llu in new index %llu\n", i,
Dave Kleikamp8c55e202007-05-24 13:04:54 -0400983 le32_to_cpu(path[i].p_idx->ei_block),
Theodore Ts'obf89d162010-10-27 21:30:14 -0400984 ext4_idx_pblock(path[i].p_idx),
Dave Kleikamp8c55e202007-05-24 13:04:54 -0400985 newblock);
Alex Tomasa86c6182006-10-11 01:21:03 -0700986 /*memmove(++fidx, path[i].p_idx++,
987 sizeof(struct ext4_extent_idx));
988 neh->eh_entries++;
989 BUG_ON(neh->eh_entries > neh->eh_max);*/
990 path[i].p_idx++;
991 m++;
992 }
993 if (m) {
994 memmove(++fidx, path[i].p_idx - m,
995 sizeof(struct ext4_extent_idx) * m);
Marcin Slusarze8546d02008-04-17 10:38:59 -0400996 le16_add_cpu(&neh->eh_entries, m);
Alex Tomasa86c6182006-10-11 01:21:03 -0700997 }
998 set_buffer_uptodate(bh);
999 unlock_buffer(bh);
1000
Frank Mayhar03901312009-01-07 00:06:22 -05001001 err = ext4_handle_dirty_metadata(handle, inode, bh);
Avantika Mathur7e028972006-12-06 20:41:33 -08001002 if (err)
Alex Tomasa86c6182006-10-11 01:21:03 -07001003 goto cleanup;
1004 brelse(bh);
1005 bh = NULL;
1006
1007 /* correct old index */
1008 if (m) {
1009 err = ext4_ext_get_access(handle, inode, path + i);
1010 if (err)
1011 goto cleanup;
Marcin Slusarze8546d02008-04-17 10:38:59 -04001012 le16_add_cpu(&path[i].p_hdr->eh_entries, -m);
Alex Tomasa86c6182006-10-11 01:21:03 -07001013 err = ext4_ext_dirty(handle, inode, path + i);
1014 if (err)
1015 goto cleanup;
1016 }
1017
1018 i--;
1019 }
1020
1021 /* insert new index */
Alex Tomasa86c6182006-10-11 01:21:03 -07001022 err = ext4_ext_insert_index(handle, inode, path + at,
1023 le32_to_cpu(border), newblock);
1024
1025cleanup:
1026 if (bh) {
1027 if (buffer_locked(bh))
1028 unlock_buffer(bh);
1029 brelse(bh);
1030 }
1031
1032 if (err) {
1033 /* free all allocated blocks in error case */
1034 for (i = 0; i < depth; i++) {
1035 if (!ablocks[i])
1036 continue;
Theodore Ts'oe6362602009-11-23 07:17:05 -05001037 ext4_free_blocks(handle, inode, 0, ablocks[i], 1,
1038 EXT4_FREE_BLOCKS_METADATA);
Alex Tomasa86c6182006-10-11 01:21:03 -07001039 }
1040 }
1041 kfree(ablocks);
1042
1043 return err;
1044}
1045
1046/*
Randy Dunlapd0d856e2006-10-11 01:21:07 -07001047 * ext4_ext_grow_indepth:
1048 * implements tree growing procedure:
1049 * - allocates new block
1050 * - moves top-level data (index block or leaf) into the new block
1051 * - initializes new top-level, creating index that points to the
1052 * just created block
Alex Tomasa86c6182006-10-11 01:21:03 -07001053 */
1054static int ext4_ext_grow_indepth(handle_t *handle, struct inode *inode,
1055 struct ext4_ext_path *path,
1056 struct ext4_extent *newext)
1057{
1058 struct ext4_ext_path *curp = path;
1059 struct ext4_extent_header *neh;
Alex Tomasa86c6182006-10-11 01:21:03 -07001060 struct buffer_head *bh;
Alex Tomasf65e6fb2006-10-11 01:21:05 -07001061 ext4_fsblk_t newblock;
Alex Tomasa86c6182006-10-11 01:21:03 -07001062 int err = 0;
1063
Aneesh Kumar K.V654b4902008-07-11 19:27:31 -04001064 newblock = ext4_ext_new_meta_block(handle, inode, path, newext, &err);
Alex Tomasa86c6182006-10-11 01:21:03 -07001065 if (newblock == 0)
1066 return err;
1067
1068 bh = sb_getblk(inode->i_sb, newblock);
1069 if (!bh) {
1070 err = -EIO;
1071 ext4_std_error(inode->i_sb, err);
1072 return err;
1073 }
1074 lock_buffer(bh);
1075
Avantika Mathur7e028972006-12-06 20:41:33 -08001076 err = ext4_journal_get_create_access(handle, bh);
1077 if (err) {
Alex Tomasa86c6182006-10-11 01:21:03 -07001078 unlock_buffer(bh);
1079 goto out;
1080 }
1081
1082 /* move top-level index/leaf into new block */
1083 memmove(bh->b_data, curp->p_hdr, sizeof(EXT4_I(inode)->i_data));
1084
1085 /* set size of new block */
1086 neh = ext_block_hdr(bh);
1087 /* old root could have indexes or leaves
1088 * so calculate e_max right way */
1089 if (ext_depth(inode))
Theodore Ts'o55ad63b2009-08-28 10:40:33 -04001090 neh->eh_max = cpu_to_le16(ext4_ext_space_block_idx(inode, 0));
Alex Tomasa86c6182006-10-11 01:21:03 -07001091 else
Theodore Ts'o55ad63b2009-08-28 10:40:33 -04001092 neh->eh_max = cpu_to_le16(ext4_ext_space_block(inode, 0));
Alex Tomasa86c6182006-10-11 01:21:03 -07001093 neh->eh_magic = EXT4_EXT_MAGIC;
1094 set_buffer_uptodate(bh);
1095 unlock_buffer(bh);
1096
Frank Mayhar03901312009-01-07 00:06:22 -05001097 err = ext4_handle_dirty_metadata(handle, inode, bh);
Avantika Mathur7e028972006-12-06 20:41:33 -08001098 if (err)
Alex Tomasa86c6182006-10-11 01:21:03 -07001099 goto out;
1100
1101 /* create index in new top-level index: num,max,pointer */
Avantika Mathur7e028972006-12-06 20:41:33 -08001102 err = ext4_ext_get_access(handle, inode, curp);
1103 if (err)
Alex Tomasa86c6182006-10-11 01:21:03 -07001104 goto out;
1105
1106 curp->p_hdr->eh_magic = EXT4_EXT_MAGIC;
Theodore Ts'o55ad63b2009-08-28 10:40:33 -04001107 curp->p_hdr->eh_max = cpu_to_le16(ext4_ext_space_root_idx(inode, 0));
Alex Tomasa86c6182006-10-11 01:21:03 -07001108 curp->p_hdr->eh_entries = cpu_to_le16(1);
1109 curp->p_idx = EXT_FIRST_INDEX(curp->p_hdr);
Dmitry Monakhove9f410b2007-07-18 09:09:15 -04001110
1111 if (path[0].p_hdr->eh_depth)
1112 curp->p_idx->ei_block =
1113 EXT_FIRST_INDEX(path[0].p_hdr)->ei_block;
1114 else
1115 curp->p_idx->ei_block =
1116 EXT_FIRST_EXTENT(path[0].p_hdr)->ee_block;
Alex Tomasf65e6fb2006-10-11 01:21:05 -07001117 ext4_idx_store_pblock(curp->p_idx, newblock);
Alex Tomasa86c6182006-10-11 01:21:03 -07001118
1119 neh = ext_inode_hdr(inode);
Mingming Cao2ae02102006-10-11 01:21:11 -07001120 ext_debug("new root: num %d(%d), lblock %d, ptr %llu\n",
Alex Tomasa86c6182006-10-11 01:21:03 -07001121 le16_to_cpu(neh->eh_entries), le16_to_cpu(neh->eh_max),
Andi Kleen5a0790c2010-06-14 13:28:03 -04001122 le32_to_cpu(EXT_FIRST_INDEX(neh)->ei_block),
Theodore Ts'obf89d162010-10-27 21:30:14 -04001123 ext4_idx_pblock(EXT_FIRST_INDEX(neh)));
Alex Tomasa86c6182006-10-11 01:21:03 -07001124
1125 neh->eh_depth = cpu_to_le16(path->p_depth + 1);
1126 err = ext4_ext_dirty(handle, inode, curp);
1127out:
1128 brelse(bh);
1129
1130 return err;
1131}
1132
1133/*
Randy Dunlapd0d856e2006-10-11 01:21:07 -07001134 * ext4_ext_create_new_leaf:
1135 * finds empty index and adds new leaf.
1136 * if no free index is found, then it requests in-depth growing.
Alex Tomasa86c6182006-10-11 01:21:03 -07001137 */
1138static int ext4_ext_create_new_leaf(handle_t *handle, struct inode *inode,
1139 struct ext4_ext_path *path,
1140 struct ext4_extent *newext)
1141{
1142 struct ext4_ext_path *curp;
1143 int depth, i, err = 0;
1144
1145repeat:
1146 i = depth = ext_depth(inode);
1147
1148 /* walk up to the tree and look for free index entry */
1149 curp = path + depth;
1150 while (i > 0 && !EXT_HAS_FREE_INDEX(curp)) {
1151 i--;
1152 curp--;
1153 }
1154
Randy Dunlapd0d856e2006-10-11 01:21:07 -07001155 /* we use already allocated block for index block,
1156 * so subsequent data blocks should be contiguous */
Alex Tomasa86c6182006-10-11 01:21:03 -07001157 if (EXT_HAS_FREE_INDEX(curp)) {
1158 /* if we found index with free entry, then use that
1159 * entry: create all needed subtree and add new leaf */
1160 err = ext4_ext_split(handle, inode, path, newext, i);
Shen Feng787e0982008-07-11 19:27:31 -04001161 if (err)
1162 goto out;
Alex Tomasa86c6182006-10-11 01:21:03 -07001163
1164 /* refill path */
1165 ext4_ext_drop_refs(path);
1166 path = ext4_ext_find_extent(inode,
Aneesh Kumar K.V725d26d2008-01-28 23:58:27 -05001167 (ext4_lblk_t)le32_to_cpu(newext->ee_block),
1168 path);
Alex Tomasa86c6182006-10-11 01:21:03 -07001169 if (IS_ERR(path))
1170 err = PTR_ERR(path);
1171 } else {
1172 /* tree is full, time to grow in depth */
1173 err = ext4_ext_grow_indepth(handle, inode, path, newext);
1174 if (err)
1175 goto out;
1176
1177 /* refill path */
1178 ext4_ext_drop_refs(path);
1179 path = ext4_ext_find_extent(inode,
Aneesh Kumar K.V725d26d2008-01-28 23:58:27 -05001180 (ext4_lblk_t)le32_to_cpu(newext->ee_block),
1181 path);
Alex Tomasa86c6182006-10-11 01:21:03 -07001182 if (IS_ERR(path)) {
1183 err = PTR_ERR(path);
1184 goto out;
1185 }
1186
1187 /*
Randy Dunlapd0d856e2006-10-11 01:21:07 -07001188 * only first (depth 0 -> 1) produces free space;
1189 * in all other cases we have to split the grown tree
Alex Tomasa86c6182006-10-11 01:21:03 -07001190 */
1191 depth = ext_depth(inode);
1192 if (path[depth].p_hdr->eh_entries == path[depth].p_hdr->eh_max) {
Randy Dunlapd0d856e2006-10-11 01:21:07 -07001193 /* now we need to split */
Alex Tomasa86c6182006-10-11 01:21:03 -07001194 goto repeat;
1195 }
1196 }
1197
1198out:
1199 return err;
1200}
1201
1202/*
Alex Tomas1988b512008-01-28 23:58:27 -05001203 * search the closest allocated block to the left for *logical
1204 * and returns it at @logical + it's physical address at @phys
1205 * if *logical is the smallest allocated block, the function
1206 * returns 0 at @phys
1207 * return value contains 0 (success) or error code
1208 */
Theodore Ts'o1f109d52010-10-27 21:30:14 -04001209static int ext4_ext_search_left(struct inode *inode,
1210 struct ext4_ext_path *path,
1211 ext4_lblk_t *logical, ext4_fsblk_t *phys)
Alex Tomas1988b512008-01-28 23:58:27 -05001212{
1213 struct ext4_extent_idx *ix;
1214 struct ext4_extent *ex;
Aneesh Kumar K.Vb939e372008-01-28 23:58:27 -05001215 int depth, ee_len;
Alex Tomas1988b512008-01-28 23:58:27 -05001216
Frank Mayhar273df552010-03-02 11:46:09 -05001217 if (unlikely(path == NULL)) {
1218 EXT4_ERROR_INODE(inode, "path == NULL *logical %d!", *logical);
1219 return -EIO;
1220 }
Alex Tomas1988b512008-01-28 23:58:27 -05001221 depth = path->p_depth;
1222 *phys = 0;
1223
1224 if (depth == 0 && path->p_ext == NULL)
1225 return 0;
1226
1227 /* usually extent in the path covers blocks smaller
1228 * then *logical, but it can be that extent is the
1229 * first one in the file */
1230
1231 ex = path[depth].p_ext;
Aneesh Kumar K.Vb939e372008-01-28 23:58:27 -05001232 ee_len = ext4_ext_get_actual_len(ex);
Alex Tomas1988b512008-01-28 23:58:27 -05001233 if (*logical < le32_to_cpu(ex->ee_block)) {
Frank Mayhar273df552010-03-02 11:46:09 -05001234 if (unlikely(EXT_FIRST_EXTENT(path[depth].p_hdr) != ex)) {
1235 EXT4_ERROR_INODE(inode,
1236 "EXT_FIRST_EXTENT != ex *logical %d ee_block %d!",
1237 *logical, le32_to_cpu(ex->ee_block));
1238 return -EIO;
1239 }
Alex Tomas1988b512008-01-28 23:58:27 -05001240 while (--depth >= 0) {
1241 ix = path[depth].p_idx;
Frank Mayhar273df552010-03-02 11:46:09 -05001242 if (unlikely(ix != EXT_FIRST_INDEX(path[depth].p_hdr))) {
1243 EXT4_ERROR_INODE(inode,
1244 "ix (%d) != EXT_FIRST_INDEX (%d) (depth %d)!",
1245 ix != NULL ? ix->ei_block : 0,
1246 EXT_FIRST_INDEX(path[depth].p_hdr) != NULL ?
1247 EXT_FIRST_INDEX(path[depth].p_hdr)->ei_block : 0,
1248 depth);
1249 return -EIO;
1250 }
Alex Tomas1988b512008-01-28 23:58:27 -05001251 }
1252 return 0;
1253 }
1254
Frank Mayhar273df552010-03-02 11:46:09 -05001255 if (unlikely(*logical < (le32_to_cpu(ex->ee_block) + ee_len))) {
1256 EXT4_ERROR_INODE(inode,
1257 "logical %d < ee_block %d + ee_len %d!",
1258 *logical, le32_to_cpu(ex->ee_block), ee_len);
1259 return -EIO;
1260 }
Alex Tomas1988b512008-01-28 23:58:27 -05001261
Aneesh Kumar K.Vb939e372008-01-28 23:58:27 -05001262 *logical = le32_to_cpu(ex->ee_block) + ee_len - 1;
Theodore Ts'obf89d162010-10-27 21:30:14 -04001263 *phys = ext4_ext_pblock(ex) + ee_len - 1;
Alex Tomas1988b512008-01-28 23:58:27 -05001264 return 0;
1265}
1266
1267/*
1268 * search the closest allocated block to the right for *logical
1269 * and returns it at @logical + it's physical address at @phys
1270 * if *logical is the smallest allocated block, the function
1271 * returns 0 at @phys
1272 * return value contains 0 (success) or error code
1273 */
Theodore Ts'o1f109d52010-10-27 21:30:14 -04001274static int ext4_ext_search_right(struct inode *inode,
1275 struct ext4_ext_path *path,
1276 ext4_lblk_t *logical, ext4_fsblk_t *phys)
Alex Tomas1988b512008-01-28 23:58:27 -05001277{
1278 struct buffer_head *bh = NULL;
1279 struct ext4_extent_header *eh;
1280 struct ext4_extent_idx *ix;
1281 struct ext4_extent *ex;
1282 ext4_fsblk_t block;
Eric Sandeen395a87b2009-03-10 18:18:47 -04001283 int depth; /* Note, NOT eh_depth; depth from top of tree */
1284 int ee_len;
Alex Tomas1988b512008-01-28 23:58:27 -05001285
Frank Mayhar273df552010-03-02 11:46:09 -05001286 if (unlikely(path == NULL)) {
1287 EXT4_ERROR_INODE(inode, "path == NULL *logical %d!", *logical);
1288 return -EIO;
1289 }
Alex Tomas1988b512008-01-28 23:58:27 -05001290 depth = path->p_depth;
1291 *phys = 0;
1292
1293 if (depth == 0 && path->p_ext == NULL)
1294 return 0;
1295
1296 /* usually extent in the path covers blocks smaller
1297 * then *logical, but it can be that extent is the
1298 * first one in the file */
1299
1300 ex = path[depth].p_ext;
Aneesh Kumar K.Vb939e372008-01-28 23:58:27 -05001301 ee_len = ext4_ext_get_actual_len(ex);
Alex Tomas1988b512008-01-28 23:58:27 -05001302 if (*logical < le32_to_cpu(ex->ee_block)) {
Frank Mayhar273df552010-03-02 11:46:09 -05001303 if (unlikely(EXT_FIRST_EXTENT(path[depth].p_hdr) != ex)) {
1304 EXT4_ERROR_INODE(inode,
1305 "first_extent(path[%d].p_hdr) != ex",
1306 depth);
1307 return -EIO;
1308 }
Alex Tomas1988b512008-01-28 23:58:27 -05001309 while (--depth >= 0) {
1310 ix = path[depth].p_idx;
Frank Mayhar273df552010-03-02 11:46:09 -05001311 if (unlikely(ix != EXT_FIRST_INDEX(path[depth].p_hdr))) {
1312 EXT4_ERROR_INODE(inode,
1313 "ix != EXT_FIRST_INDEX *logical %d!",
1314 *logical);
1315 return -EIO;
1316 }
Alex Tomas1988b512008-01-28 23:58:27 -05001317 }
1318 *logical = le32_to_cpu(ex->ee_block);
Theodore Ts'obf89d162010-10-27 21:30:14 -04001319 *phys = ext4_ext_pblock(ex);
Alex Tomas1988b512008-01-28 23:58:27 -05001320 return 0;
1321 }
1322
Frank Mayhar273df552010-03-02 11:46:09 -05001323 if (unlikely(*logical < (le32_to_cpu(ex->ee_block) + ee_len))) {
1324 EXT4_ERROR_INODE(inode,
1325 "logical %d < ee_block %d + ee_len %d!",
1326 *logical, le32_to_cpu(ex->ee_block), ee_len);
1327 return -EIO;
1328 }
Alex Tomas1988b512008-01-28 23:58:27 -05001329
1330 if (ex != EXT_LAST_EXTENT(path[depth].p_hdr)) {
1331 /* next allocated block in this leaf */
1332 ex++;
1333 *logical = le32_to_cpu(ex->ee_block);
Theodore Ts'obf89d162010-10-27 21:30:14 -04001334 *phys = ext4_ext_pblock(ex);
Alex Tomas1988b512008-01-28 23:58:27 -05001335 return 0;
1336 }
1337
1338 /* go up and search for index to the right */
1339 while (--depth >= 0) {
1340 ix = path[depth].p_idx;
1341 if (ix != EXT_LAST_INDEX(path[depth].p_hdr))
Wu Fengguang25f1ee32008-11-25 17:24:23 -05001342 goto got_index;
Alex Tomas1988b512008-01-28 23:58:27 -05001343 }
1344
Wu Fengguang25f1ee32008-11-25 17:24:23 -05001345 /* we've gone up to the root and found no index to the right */
1346 return 0;
Alex Tomas1988b512008-01-28 23:58:27 -05001347
Wu Fengguang25f1ee32008-11-25 17:24:23 -05001348got_index:
Alex Tomas1988b512008-01-28 23:58:27 -05001349 /* we've found index to the right, let's
1350 * follow it and find the closest allocated
1351 * block to the right */
1352 ix++;
Theodore Ts'obf89d162010-10-27 21:30:14 -04001353 block = ext4_idx_pblock(ix);
Alex Tomas1988b512008-01-28 23:58:27 -05001354 while (++depth < path->p_depth) {
1355 bh = sb_bread(inode->i_sb, block);
1356 if (bh == NULL)
1357 return -EIO;
1358 eh = ext_block_hdr(bh);
Eric Sandeen395a87b2009-03-10 18:18:47 -04001359 /* subtract from p_depth to get proper eh_depth */
Aneesh Kumar K.V56b19862009-03-12 09:51:20 -04001360 if (ext4_ext_check(inode, eh, path->p_depth - depth)) {
Alex Tomas1988b512008-01-28 23:58:27 -05001361 put_bh(bh);
1362 return -EIO;
1363 }
1364 ix = EXT_FIRST_INDEX(eh);
Theodore Ts'obf89d162010-10-27 21:30:14 -04001365 block = ext4_idx_pblock(ix);
Alex Tomas1988b512008-01-28 23:58:27 -05001366 put_bh(bh);
1367 }
1368
1369 bh = sb_bread(inode->i_sb, block);
1370 if (bh == NULL)
1371 return -EIO;
1372 eh = ext_block_hdr(bh);
Aneesh Kumar K.V56b19862009-03-12 09:51:20 -04001373 if (ext4_ext_check(inode, eh, path->p_depth - depth)) {
Alex Tomas1988b512008-01-28 23:58:27 -05001374 put_bh(bh);
1375 return -EIO;
1376 }
1377 ex = EXT_FIRST_EXTENT(eh);
1378 *logical = le32_to_cpu(ex->ee_block);
Theodore Ts'obf89d162010-10-27 21:30:14 -04001379 *phys = ext4_ext_pblock(ex);
Alex Tomas1988b512008-01-28 23:58:27 -05001380 put_bh(bh);
1381 return 0;
Alex Tomas1988b512008-01-28 23:58:27 -05001382}
1383
1384/*
Randy Dunlapd0d856e2006-10-11 01:21:07 -07001385 * ext4_ext_next_allocated_block:
1386 * returns allocated block in subsequent extent or EXT_MAX_BLOCK.
1387 * NOTE: it considers block number from index entry as
1388 * allocated block. Thus, index entries have to be consistent
1389 * with leaves.
Alex Tomasa86c6182006-10-11 01:21:03 -07001390 */
Aneesh Kumar K.V725d26d2008-01-28 23:58:27 -05001391static ext4_lblk_t
Alex Tomasa86c6182006-10-11 01:21:03 -07001392ext4_ext_next_allocated_block(struct ext4_ext_path *path)
1393{
1394 int depth;
1395
1396 BUG_ON(path == NULL);
1397 depth = path->p_depth;
1398
1399 if (depth == 0 && path->p_ext == NULL)
1400 return EXT_MAX_BLOCK;
1401
1402 while (depth >= 0) {
1403 if (depth == path->p_depth) {
1404 /* leaf */
1405 if (path[depth].p_ext !=
1406 EXT_LAST_EXTENT(path[depth].p_hdr))
1407 return le32_to_cpu(path[depth].p_ext[1].ee_block);
1408 } else {
1409 /* index */
1410 if (path[depth].p_idx !=
1411 EXT_LAST_INDEX(path[depth].p_hdr))
1412 return le32_to_cpu(path[depth].p_idx[1].ei_block);
1413 }
1414 depth--;
1415 }
1416
1417 return EXT_MAX_BLOCK;
1418}
1419
1420/*
Randy Dunlapd0d856e2006-10-11 01:21:07 -07001421 * ext4_ext_next_leaf_block:
Alex Tomasa86c6182006-10-11 01:21:03 -07001422 * returns first allocated block from next leaf or EXT_MAX_BLOCK
1423 */
Aneesh Kumar K.V725d26d2008-01-28 23:58:27 -05001424static ext4_lblk_t ext4_ext_next_leaf_block(struct inode *inode,
Andrew Morton63f57932006-10-11 01:21:24 -07001425 struct ext4_ext_path *path)
Alex Tomasa86c6182006-10-11 01:21:03 -07001426{
1427 int depth;
1428
1429 BUG_ON(path == NULL);
1430 depth = path->p_depth;
1431
1432 /* zero-tree has no leaf blocks at all */
1433 if (depth == 0)
1434 return EXT_MAX_BLOCK;
1435
1436 /* go to index block */
1437 depth--;
1438
1439 while (depth >= 0) {
1440 if (path[depth].p_idx !=
1441 EXT_LAST_INDEX(path[depth].p_hdr))
Aneesh Kumar K.V725d26d2008-01-28 23:58:27 -05001442 return (ext4_lblk_t)
1443 le32_to_cpu(path[depth].p_idx[1].ei_block);
Alex Tomasa86c6182006-10-11 01:21:03 -07001444 depth--;
1445 }
1446
1447 return EXT_MAX_BLOCK;
1448}
1449
1450/*
Randy Dunlapd0d856e2006-10-11 01:21:07 -07001451 * ext4_ext_correct_indexes:
1452 * if leaf gets modified and modified extent is first in the leaf,
1453 * then we have to correct all indexes above.
Alex Tomasa86c6182006-10-11 01:21:03 -07001454 * TODO: do we need to correct tree in all cases?
1455 */
Aneesh Kumar K.V1d03ec92008-01-28 23:58:27 -05001456static int ext4_ext_correct_indexes(handle_t *handle, struct inode *inode,
Alex Tomasa86c6182006-10-11 01:21:03 -07001457 struct ext4_ext_path *path)
1458{
1459 struct ext4_extent_header *eh;
1460 int depth = ext_depth(inode);
1461 struct ext4_extent *ex;
1462 __le32 border;
1463 int k, err = 0;
1464
1465 eh = path[depth].p_hdr;
1466 ex = path[depth].p_ext;
Frank Mayhar273df552010-03-02 11:46:09 -05001467
1468 if (unlikely(ex == NULL || eh == NULL)) {
1469 EXT4_ERROR_INODE(inode,
1470 "ex %p == NULL or eh %p == NULL", ex, eh);
1471 return -EIO;
1472 }
Alex Tomasa86c6182006-10-11 01:21:03 -07001473
1474 if (depth == 0) {
1475 /* there is no tree at all */
1476 return 0;
1477 }
1478
1479 if (ex != EXT_FIRST_EXTENT(eh)) {
1480 /* we correct tree if first leaf got modified only */
1481 return 0;
1482 }
1483
1484 /*
Randy Dunlapd0d856e2006-10-11 01:21:07 -07001485 * TODO: we need correction if border is smaller than current one
Alex Tomasa86c6182006-10-11 01:21:03 -07001486 */
1487 k = depth - 1;
1488 border = path[depth].p_ext->ee_block;
Avantika Mathur7e028972006-12-06 20:41:33 -08001489 err = ext4_ext_get_access(handle, inode, path + k);
1490 if (err)
Alex Tomasa86c6182006-10-11 01:21:03 -07001491 return err;
1492 path[k].p_idx->ei_block = border;
Avantika Mathur7e028972006-12-06 20:41:33 -08001493 err = ext4_ext_dirty(handle, inode, path + k);
1494 if (err)
Alex Tomasa86c6182006-10-11 01:21:03 -07001495 return err;
1496
1497 while (k--) {
1498 /* change all left-side indexes */
1499 if (path[k+1].p_idx != EXT_FIRST_INDEX(path[k+1].p_hdr))
1500 break;
Avantika Mathur7e028972006-12-06 20:41:33 -08001501 err = ext4_ext_get_access(handle, inode, path + k);
1502 if (err)
Alex Tomasa86c6182006-10-11 01:21:03 -07001503 break;
1504 path[k].p_idx->ei_block = border;
Avantika Mathur7e028972006-12-06 20:41:33 -08001505 err = ext4_ext_dirty(handle, inode, path + k);
1506 if (err)
Alex Tomasa86c6182006-10-11 01:21:03 -07001507 break;
1508 }
1509
1510 return err;
1511}
1512
Akira Fujita748de672009-06-17 19:24:03 -04001513int
Alex Tomasa86c6182006-10-11 01:21:03 -07001514ext4_can_extents_be_merged(struct inode *inode, struct ext4_extent *ex1,
1515 struct ext4_extent *ex2)
1516{
Amit Arora749269f2007-07-18 09:02:56 -04001517 unsigned short ext1_ee_len, ext2_ee_len, max_len;
Amit Aroraa2df2a62007-07-17 21:42:41 -04001518
1519 /*
1520 * Make sure that either both extents are uninitialized, or
1521 * both are _not_.
1522 */
1523 if (ext4_ext_is_uninitialized(ex1) ^ ext4_ext_is_uninitialized(ex2))
1524 return 0;
1525
Amit Arora749269f2007-07-18 09:02:56 -04001526 if (ext4_ext_is_uninitialized(ex1))
1527 max_len = EXT_UNINIT_MAX_LEN;
1528 else
1529 max_len = EXT_INIT_MAX_LEN;
1530
Amit Aroraa2df2a62007-07-17 21:42:41 -04001531 ext1_ee_len = ext4_ext_get_actual_len(ex1);
1532 ext2_ee_len = ext4_ext_get_actual_len(ex2);
1533
1534 if (le32_to_cpu(ex1->ee_block) + ext1_ee_len !=
Andrew Morton63f57932006-10-11 01:21:24 -07001535 le32_to_cpu(ex2->ee_block))
Alex Tomasa86c6182006-10-11 01:21:03 -07001536 return 0;
1537
Suparna Bhattacharya471d4012006-10-11 01:21:06 -07001538 /*
1539 * To allow future support for preallocated extents to be added
1540 * as an RO_COMPAT feature, refuse to merge to extents if
Randy Dunlapd0d856e2006-10-11 01:21:07 -07001541 * this can result in the top bit of ee_len being set.
Suparna Bhattacharya471d4012006-10-11 01:21:06 -07001542 */
Amit Arora749269f2007-07-18 09:02:56 -04001543 if (ext1_ee_len + ext2_ee_len > max_len)
Suparna Bhattacharya471d4012006-10-11 01:21:06 -07001544 return 0;
Robert P. J. Daybbf2f9f2007-02-17 19:20:16 +01001545#ifdef AGGRESSIVE_TEST
Aneesh Kumar K.Vb939e372008-01-28 23:58:27 -05001546 if (ext1_ee_len >= 4)
Alex Tomasa86c6182006-10-11 01:21:03 -07001547 return 0;
1548#endif
1549
Theodore Ts'obf89d162010-10-27 21:30:14 -04001550 if (ext4_ext_pblock(ex1) + ext1_ee_len == ext4_ext_pblock(ex2))
Alex Tomasa86c6182006-10-11 01:21:03 -07001551 return 1;
1552 return 0;
1553}
1554
1555/*
Amit Arora56055d32007-07-17 21:42:38 -04001556 * This function tries to merge the "ex" extent to the next extent in the tree.
1557 * It always tries to merge towards right. If you want to merge towards
1558 * left, pass "ex - 1" as argument instead of "ex".
1559 * Returns 0 if the extents (ex and ex+1) were _not_ merged and returns
1560 * 1 if they got merged.
1561 */
Theodore Ts'o1f109d52010-10-27 21:30:14 -04001562static int ext4_ext_try_to_merge(struct inode *inode,
1563 struct ext4_ext_path *path,
1564 struct ext4_extent *ex)
Amit Arora56055d32007-07-17 21:42:38 -04001565{
1566 struct ext4_extent_header *eh;
1567 unsigned int depth, len;
1568 int merge_done = 0;
1569 int uninitialized = 0;
1570
1571 depth = ext_depth(inode);
1572 BUG_ON(path[depth].p_hdr == NULL);
1573 eh = path[depth].p_hdr;
1574
1575 while (ex < EXT_LAST_EXTENT(eh)) {
1576 if (!ext4_can_extents_be_merged(inode, ex, ex + 1))
1577 break;
1578 /* merge with next extent! */
1579 if (ext4_ext_is_uninitialized(ex))
1580 uninitialized = 1;
1581 ex->ee_len = cpu_to_le16(ext4_ext_get_actual_len(ex)
1582 + ext4_ext_get_actual_len(ex + 1));
1583 if (uninitialized)
1584 ext4_ext_mark_uninitialized(ex);
1585
1586 if (ex + 1 < EXT_LAST_EXTENT(eh)) {
1587 len = (EXT_LAST_EXTENT(eh) - ex - 1)
1588 * sizeof(struct ext4_extent);
1589 memmove(ex + 1, ex + 2, len);
1590 }
Marcin Slusarze8546d02008-04-17 10:38:59 -04001591 le16_add_cpu(&eh->eh_entries, -1);
Amit Arora56055d32007-07-17 21:42:38 -04001592 merge_done = 1;
1593 WARN_ON(eh->eh_entries == 0);
1594 if (!eh->eh_entries)
Theodore Ts'o24676da2010-05-16 21:00:00 -04001595 EXT4_ERROR_INODE(inode, "eh->eh_entries = 0!");
Amit Arora56055d32007-07-17 21:42:38 -04001596 }
1597
1598 return merge_done;
1599}
1600
1601/*
Amit Arora25d14f92007-05-24 13:04:13 -04001602 * check if a portion of the "newext" extent overlaps with an
1603 * existing extent.
1604 *
1605 * If there is an overlap discovered, it updates the length of the newext
1606 * such that there will be no overlap, and then returns 1.
1607 * If there is no overlap found, it returns 0.
1608 */
Theodore Ts'o1f109d52010-10-27 21:30:14 -04001609static unsigned int ext4_ext_check_overlap(struct inode *inode,
1610 struct ext4_extent *newext,
1611 struct ext4_ext_path *path)
Amit Arora25d14f92007-05-24 13:04:13 -04001612{
Aneesh Kumar K.V725d26d2008-01-28 23:58:27 -05001613 ext4_lblk_t b1, b2;
Amit Arora25d14f92007-05-24 13:04:13 -04001614 unsigned int depth, len1;
1615 unsigned int ret = 0;
1616
1617 b1 = le32_to_cpu(newext->ee_block);
Amit Aroraa2df2a62007-07-17 21:42:41 -04001618 len1 = ext4_ext_get_actual_len(newext);
Amit Arora25d14f92007-05-24 13:04:13 -04001619 depth = ext_depth(inode);
1620 if (!path[depth].p_ext)
1621 goto out;
1622 b2 = le32_to_cpu(path[depth].p_ext->ee_block);
1623
1624 /*
1625 * get the next allocated block if the extent in the path
Theodore Ts'o2b2d6d02008-07-26 16:15:44 -04001626 * is before the requested block(s)
Amit Arora25d14f92007-05-24 13:04:13 -04001627 */
1628 if (b2 < b1) {
1629 b2 = ext4_ext_next_allocated_block(path);
1630 if (b2 == EXT_MAX_BLOCK)
1631 goto out;
1632 }
1633
Aneesh Kumar K.V725d26d2008-01-28 23:58:27 -05001634 /* check for wrap through zero on extent logical start block*/
Amit Arora25d14f92007-05-24 13:04:13 -04001635 if (b1 + len1 < b1) {
1636 len1 = EXT_MAX_BLOCK - b1;
1637 newext->ee_len = cpu_to_le16(len1);
1638 ret = 1;
1639 }
1640
1641 /* check for overlap */
1642 if (b1 + len1 > b2) {
1643 newext->ee_len = cpu_to_le16(b2 - b1);
1644 ret = 1;
1645 }
1646out:
1647 return ret;
1648}
1649
1650/*
Randy Dunlapd0d856e2006-10-11 01:21:07 -07001651 * ext4_ext_insert_extent:
1652 * tries to merge requsted extent into the existing extent or
1653 * inserts requested extent as new one into the tree,
1654 * creating new leaf in the no-space case.
Alex Tomasa86c6182006-10-11 01:21:03 -07001655 */
1656int ext4_ext_insert_extent(handle_t *handle, struct inode *inode,
1657 struct ext4_ext_path *path,
Mingming Cao00314622009-09-28 15:49:08 -04001658 struct ext4_extent *newext, int flag)
Alex Tomasa86c6182006-10-11 01:21:03 -07001659{
Theodore Ts'oaf5bc922008-09-08 22:25:24 -04001660 struct ext4_extent_header *eh;
Alex Tomasa86c6182006-10-11 01:21:03 -07001661 struct ext4_extent *ex, *fex;
1662 struct ext4_extent *nearex; /* nearest extent */
1663 struct ext4_ext_path *npath = NULL;
Aneesh Kumar K.V725d26d2008-01-28 23:58:27 -05001664 int depth, len, err;
1665 ext4_lblk_t next;
Amit Aroraa2df2a62007-07-17 21:42:41 -04001666 unsigned uninitialized = 0;
Alex Tomasa86c6182006-10-11 01:21:03 -07001667
Frank Mayhar273df552010-03-02 11:46:09 -05001668 if (unlikely(ext4_ext_get_actual_len(newext) == 0)) {
1669 EXT4_ERROR_INODE(inode, "ext4_ext_get_actual_len(newext) == 0");
1670 return -EIO;
1671 }
Alex Tomasa86c6182006-10-11 01:21:03 -07001672 depth = ext_depth(inode);
1673 ex = path[depth].p_ext;
Frank Mayhar273df552010-03-02 11:46:09 -05001674 if (unlikely(path[depth].p_hdr == NULL)) {
1675 EXT4_ERROR_INODE(inode, "path[%d].p_hdr == NULL", depth);
1676 return -EIO;
1677 }
Alex Tomasa86c6182006-10-11 01:21:03 -07001678
1679 /* try to insert block into found extent and return */
Jiaying Zhang744692d2010-03-04 16:14:02 -05001680 if (ex && !(flag & EXT4_GET_BLOCKS_PRE_IO)
Mingming Cao00314622009-09-28 15:49:08 -04001681 && ext4_can_extents_be_merged(inode, ex, newext)) {
Mingming553f9002009-09-18 13:34:55 -04001682 ext_debug("append [%d]%d block to %d:[%d]%d (from %llu)\n",
Theodore Ts'obf89d162010-10-27 21:30:14 -04001683 ext4_ext_is_uninitialized(newext),
1684 ext4_ext_get_actual_len(newext),
1685 le32_to_cpu(ex->ee_block),
1686 ext4_ext_is_uninitialized(ex),
1687 ext4_ext_get_actual_len(ex),
1688 ext4_ext_pblock(ex));
Avantika Mathur7e028972006-12-06 20:41:33 -08001689 err = ext4_ext_get_access(handle, inode, path + depth);
1690 if (err)
Alex Tomasa86c6182006-10-11 01:21:03 -07001691 return err;
Amit Aroraa2df2a62007-07-17 21:42:41 -04001692
1693 /*
1694 * ext4_can_extents_be_merged should have checked that either
1695 * both extents are uninitialized, or both aren't. Thus we
1696 * need to check only one of them here.
1697 */
1698 if (ext4_ext_is_uninitialized(ex))
1699 uninitialized = 1;
1700 ex->ee_len = cpu_to_le16(ext4_ext_get_actual_len(ex)
1701 + ext4_ext_get_actual_len(newext));
1702 if (uninitialized)
1703 ext4_ext_mark_uninitialized(ex);
Alex Tomasa86c6182006-10-11 01:21:03 -07001704 eh = path[depth].p_hdr;
1705 nearex = ex;
1706 goto merge;
1707 }
1708
1709repeat:
1710 depth = ext_depth(inode);
1711 eh = path[depth].p_hdr;
1712 if (le16_to_cpu(eh->eh_entries) < le16_to_cpu(eh->eh_max))
1713 goto has_space;
1714
1715 /* probably next leaf has space for us? */
1716 fex = EXT_LAST_EXTENT(eh);
1717 next = ext4_ext_next_leaf_block(inode, path);
1718 if (le32_to_cpu(newext->ee_block) > le32_to_cpu(fex->ee_block)
1719 && next != EXT_MAX_BLOCK) {
1720 ext_debug("next leaf block - %d\n", next);
1721 BUG_ON(npath != NULL);
1722 npath = ext4_ext_find_extent(inode, next, NULL);
1723 if (IS_ERR(npath))
1724 return PTR_ERR(npath);
1725 BUG_ON(npath->p_depth != path->p_depth);
1726 eh = npath[depth].p_hdr;
1727 if (le16_to_cpu(eh->eh_entries) < le16_to_cpu(eh->eh_max)) {
1728 ext_debug("next leaf isnt full(%d)\n",
1729 le16_to_cpu(eh->eh_entries));
1730 path = npath;
1731 goto repeat;
1732 }
1733 ext_debug("next leaf has no free space(%d,%d)\n",
1734 le16_to_cpu(eh->eh_entries), le16_to_cpu(eh->eh_max));
1735 }
1736
1737 /*
Randy Dunlapd0d856e2006-10-11 01:21:07 -07001738 * There is no free space in the found leaf.
1739 * We're gonna add a new leaf in the tree.
Alex Tomasa86c6182006-10-11 01:21:03 -07001740 */
1741 err = ext4_ext_create_new_leaf(handle, inode, path, newext);
1742 if (err)
1743 goto cleanup;
1744 depth = ext_depth(inode);
1745 eh = path[depth].p_hdr;
1746
1747has_space:
1748 nearex = path[depth].p_ext;
1749
Avantika Mathur7e028972006-12-06 20:41:33 -08001750 err = ext4_ext_get_access(handle, inode, path + depth);
1751 if (err)
Alex Tomasa86c6182006-10-11 01:21:03 -07001752 goto cleanup;
1753
1754 if (!nearex) {
1755 /* there is no extent in this leaf, create first one */
Mingming553f9002009-09-18 13:34:55 -04001756 ext_debug("first extent in the leaf: %d:%llu:[%d]%d\n",
Dave Kleikamp8c55e202007-05-24 13:04:54 -04001757 le32_to_cpu(newext->ee_block),
Theodore Ts'obf89d162010-10-27 21:30:14 -04001758 ext4_ext_pblock(newext),
Mingming553f9002009-09-18 13:34:55 -04001759 ext4_ext_is_uninitialized(newext),
Amit Aroraa2df2a62007-07-17 21:42:41 -04001760 ext4_ext_get_actual_len(newext));
Alex Tomasa86c6182006-10-11 01:21:03 -07001761 path[depth].p_ext = EXT_FIRST_EXTENT(eh);
1762 } else if (le32_to_cpu(newext->ee_block)
Dave Kleikamp8c55e202007-05-24 13:04:54 -04001763 > le32_to_cpu(nearex->ee_block)) {
Alex Tomasa86c6182006-10-11 01:21:03 -07001764/* BUG_ON(newext->ee_block == nearex->ee_block); */
1765 if (nearex != EXT_LAST_EXTENT(eh)) {
1766 len = EXT_MAX_EXTENT(eh) - nearex;
1767 len = (len - 1) * sizeof(struct ext4_extent);
1768 len = len < 0 ? 0 : len;
Mingming553f9002009-09-18 13:34:55 -04001769 ext_debug("insert %d:%llu:[%d]%d after: nearest 0x%p, "
Alex Tomasa86c6182006-10-11 01:21:03 -07001770 "move %d from 0x%p to 0x%p\n",
Dave Kleikamp8c55e202007-05-24 13:04:54 -04001771 le32_to_cpu(newext->ee_block),
Theodore Ts'obf89d162010-10-27 21:30:14 -04001772 ext4_ext_pblock(newext),
Mingming553f9002009-09-18 13:34:55 -04001773 ext4_ext_is_uninitialized(newext),
Amit Aroraa2df2a62007-07-17 21:42:41 -04001774 ext4_ext_get_actual_len(newext),
Alex Tomasa86c6182006-10-11 01:21:03 -07001775 nearex, len, nearex + 1, nearex + 2);
1776 memmove(nearex + 2, nearex + 1, len);
1777 }
1778 path[depth].p_ext = nearex + 1;
1779 } else {
1780 BUG_ON(newext->ee_block == nearex->ee_block);
1781 len = (EXT_MAX_EXTENT(eh) - nearex) * sizeof(struct ext4_extent);
1782 len = len < 0 ? 0 : len;
Mingming553f9002009-09-18 13:34:55 -04001783 ext_debug("insert %d:%llu:[%d]%d before: nearest 0x%p, "
Alex Tomasa86c6182006-10-11 01:21:03 -07001784 "move %d from 0x%p to 0x%p\n",
1785 le32_to_cpu(newext->ee_block),
Theodore Ts'obf89d162010-10-27 21:30:14 -04001786 ext4_ext_pblock(newext),
Mingming553f9002009-09-18 13:34:55 -04001787 ext4_ext_is_uninitialized(newext),
Amit Aroraa2df2a62007-07-17 21:42:41 -04001788 ext4_ext_get_actual_len(newext),
Alex Tomasa86c6182006-10-11 01:21:03 -07001789 nearex, len, nearex + 1, nearex + 2);
1790 memmove(nearex + 1, nearex, len);
1791 path[depth].p_ext = nearex;
1792 }
1793
Marcin Slusarze8546d02008-04-17 10:38:59 -04001794 le16_add_cpu(&eh->eh_entries, 1);
Alex Tomasa86c6182006-10-11 01:21:03 -07001795 nearex = path[depth].p_ext;
1796 nearex->ee_block = newext->ee_block;
Theodore Ts'obf89d162010-10-27 21:30:14 -04001797 ext4_ext_store_pblock(nearex, ext4_ext_pblock(newext));
Alex Tomasa86c6182006-10-11 01:21:03 -07001798 nearex->ee_len = newext->ee_len;
Alex Tomasa86c6182006-10-11 01:21:03 -07001799
1800merge:
1801 /* try to merge extents to the right */
Jiaying Zhang744692d2010-03-04 16:14:02 -05001802 if (!(flag & EXT4_GET_BLOCKS_PRE_IO))
Mingming Cao00314622009-09-28 15:49:08 -04001803 ext4_ext_try_to_merge(inode, path, nearex);
Alex Tomasa86c6182006-10-11 01:21:03 -07001804
1805 /* try to merge extents to the left */
1806
1807 /* time to correct all indexes above */
1808 err = ext4_ext_correct_indexes(handle, inode, path);
1809 if (err)
1810 goto cleanup;
1811
1812 err = ext4_ext_dirty(handle, inode, path + depth);
1813
1814cleanup:
1815 if (npath) {
1816 ext4_ext_drop_refs(npath);
1817 kfree(npath);
1818 }
Alex Tomasa86c6182006-10-11 01:21:03 -07001819 ext4_ext_invalidate_cache(inode);
1820 return err;
1821}
1822
Theodore Ts'o1f109d52010-10-27 21:30:14 -04001823static int ext4_ext_walk_space(struct inode *inode, ext4_lblk_t block,
1824 ext4_lblk_t num, ext_prepare_callback func,
1825 void *cbdata)
Eric Sandeen6873fa02008-10-07 00:46:36 -04001826{
1827 struct ext4_ext_path *path = NULL;
1828 struct ext4_ext_cache cbex;
1829 struct ext4_extent *ex;
1830 ext4_lblk_t next, start = 0, end = 0;
1831 ext4_lblk_t last = block + num;
1832 int depth, exists, err = 0;
1833
1834 BUG_ON(func == NULL);
1835 BUG_ON(inode == NULL);
1836
1837 while (block < last && block != EXT_MAX_BLOCK) {
1838 num = last - block;
1839 /* find extent for this block */
Theodore Ts'ofab3a542009-12-09 21:30:02 -05001840 down_read(&EXT4_I(inode)->i_data_sem);
Eric Sandeen6873fa02008-10-07 00:46:36 -04001841 path = ext4_ext_find_extent(inode, block, path);
Theodore Ts'ofab3a542009-12-09 21:30:02 -05001842 up_read(&EXT4_I(inode)->i_data_sem);
Eric Sandeen6873fa02008-10-07 00:46:36 -04001843 if (IS_ERR(path)) {
1844 err = PTR_ERR(path);
1845 path = NULL;
1846 break;
1847 }
1848
1849 depth = ext_depth(inode);
Frank Mayhar273df552010-03-02 11:46:09 -05001850 if (unlikely(path[depth].p_hdr == NULL)) {
1851 EXT4_ERROR_INODE(inode, "path[%d].p_hdr == NULL", depth);
1852 err = -EIO;
1853 break;
1854 }
Eric Sandeen6873fa02008-10-07 00:46:36 -04001855 ex = path[depth].p_ext;
1856 next = ext4_ext_next_allocated_block(path);
1857
1858 exists = 0;
1859 if (!ex) {
1860 /* there is no extent yet, so try to allocate
1861 * all requested space */
1862 start = block;
1863 end = block + num;
1864 } else if (le32_to_cpu(ex->ee_block) > block) {
1865 /* need to allocate space before found extent */
1866 start = block;
1867 end = le32_to_cpu(ex->ee_block);
1868 if (block + num < end)
1869 end = block + num;
1870 } else if (block >= le32_to_cpu(ex->ee_block)
1871 + ext4_ext_get_actual_len(ex)) {
1872 /* need to allocate space after found extent */
1873 start = block;
1874 end = block + num;
1875 if (end >= next)
1876 end = next;
1877 } else if (block >= le32_to_cpu(ex->ee_block)) {
1878 /*
1879 * some part of requested space is covered
1880 * by found extent
1881 */
1882 start = block;
1883 end = le32_to_cpu(ex->ee_block)
1884 + ext4_ext_get_actual_len(ex);
1885 if (block + num < end)
1886 end = block + num;
1887 exists = 1;
1888 } else {
1889 BUG();
1890 }
1891 BUG_ON(end <= start);
1892
1893 if (!exists) {
1894 cbex.ec_block = start;
1895 cbex.ec_len = end - start;
1896 cbex.ec_start = 0;
Eric Sandeen6873fa02008-10-07 00:46:36 -04001897 } else {
1898 cbex.ec_block = le32_to_cpu(ex->ee_block);
1899 cbex.ec_len = ext4_ext_get_actual_len(ex);
Theodore Ts'obf89d162010-10-27 21:30:14 -04001900 cbex.ec_start = ext4_ext_pblock(ex);
Eric Sandeen6873fa02008-10-07 00:46:36 -04001901 }
1902
Frank Mayhar273df552010-03-02 11:46:09 -05001903 if (unlikely(cbex.ec_len == 0)) {
1904 EXT4_ERROR_INODE(inode, "cbex.ec_len == 0");
1905 err = -EIO;
1906 break;
1907 }
Eric Sandeen6873fa02008-10-07 00:46:36 -04001908 err = func(inode, path, &cbex, ex, cbdata);
1909 ext4_ext_drop_refs(path);
1910
1911 if (err < 0)
1912 break;
1913
1914 if (err == EXT_REPEAT)
1915 continue;
1916 else if (err == EXT_BREAK) {
1917 err = 0;
1918 break;
1919 }
1920
1921 if (ext_depth(inode) != depth) {
1922 /* depth was changed. we have to realloc path */
1923 kfree(path);
1924 path = NULL;
1925 }
1926
1927 block = cbex.ec_block + cbex.ec_len;
1928 }
1929
1930 if (path) {
1931 ext4_ext_drop_refs(path);
1932 kfree(path);
1933 }
1934
1935 return err;
1936}
1937
Avantika Mathur09b88252006-12-06 20:41:36 -08001938static void
Aneesh Kumar K.V725d26d2008-01-28 23:58:27 -05001939ext4_ext_put_in_cache(struct inode *inode, ext4_lblk_t block,
Theodore Ts'ob05e6ae2011-01-10 12:13:26 -05001940 __u32 len, ext4_fsblk_t start)
Alex Tomasa86c6182006-10-11 01:21:03 -07001941{
1942 struct ext4_ext_cache *cex;
1943 BUG_ON(len == 0);
Theodore Ts'o2ec0ae32009-05-15 09:07:28 -04001944 spin_lock(&EXT4_I(inode)->i_block_reservation_lock);
Alex Tomasa86c6182006-10-11 01:21:03 -07001945 cex = &EXT4_I(inode)->i_cached_extent;
Alex Tomasa86c6182006-10-11 01:21:03 -07001946 cex->ec_block = block;
1947 cex->ec_len = len;
1948 cex->ec_start = start;
Theodore Ts'o2ec0ae32009-05-15 09:07:28 -04001949 spin_unlock(&EXT4_I(inode)->i_block_reservation_lock);
Alex Tomasa86c6182006-10-11 01:21:03 -07001950}
1951
1952/*
Randy Dunlapd0d856e2006-10-11 01:21:07 -07001953 * ext4_ext_put_gap_in_cache:
1954 * calculate boundaries of the gap that the requested block fits into
Alex Tomasa86c6182006-10-11 01:21:03 -07001955 * and cache this gap
1956 */
Avantika Mathur09b88252006-12-06 20:41:36 -08001957static void
Alex Tomasa86c6182006-10-11 01:21:03 -07001958ext4_ext_put_gap_in_cache(struct inode *inode, struct ext4_ext_path *path,
Aneesh Kumar K.V725d26d2008-01-28 23:58:27 -05001959 ext4_lblk_t block)
Alex Tomasa86c6182006-10-11 01:21:03 -07001960{
1961 int depth = ext_depth(inode);
Aneesh Kumar K.V725d26d2008-01-28 23:58:27 -05001962 unsigned long len;
1963 ext4_lblk_t lblock;
Alex Tomasa86c6182006-10-11 01:21:03 -07001964 struct ext4_extent *ex;
1965
1966 ex = path[depth].p_ext;
1967 if (ex == NULL) {
1968 /* there is no extent yet, so gap is [0;-] */
1969 lblock = 0;
1970 len = EXT_MAX_BLOCK;
1971 ext_debug("cache gap(whole file):");
1972 } else if (block < le32_to_cpu(ex->ee_block)) {
1973 lblock = block;
1974 len = le32_to_cpu(ex->ee_block) - block;
Eric Sandeenbba90742008-01-28 23:58:27 -05001975 ext_debug("cache gap(before): %u [%u:%u]",
1976 block,
1977 le32_to_cpu(ex->ee_block),
1978 ext4_ext_get_actual_len(ex));
Alex Tomasa86c6182006-10-11 01:21:03 -07001979 } else if (block >= le32_to_cpu(ex->ee_block)
Amit Aroraa2df2a62007-07-17 21:42:41 -04001980 + ext4_ext_get_actual_len(ex)) {
Aneesh Kumar K.V725d26d2008-01-28 23:58:27 -05001981 ext4_lblk_t next;
Dave Kleikamp8c55e202007-05-24 13:04:54 -04001982 lblock = le32_to_cpu(ex->ee_block)
Amit Aroraa2df2a62007-07-17 21:42:41 -04001983 + ext4_ext_get_actual_len(ex);
Aneesh Kumar K.V725d26d2008-01-28 23:58:27 -05001984
1985 next = ext4_ext_next_allocated_block(path);
Eric Sandeenbba90742008-01-28 23:58:27 -05001986 ext_debug("cache gap(after): [%u:%u] %u",
1987 le32_to_cpu(ex->ee_block),
1988 ext4_ext_get_actual_len(ex),
1989 block);
Aneesh Kumar K.V725d26d2008-01-28 23:58:27 -05001990 BUG_ON(next == lblock);
1991 len = next - lblock;
Alex Tomasa86c6182006-10-11 01:21:03 -07001992 } else {
1993 lblock = len = 0;
1994 BUG();
1995 }
1996
Eric Sandeenbba90742008-01-28 23:58:27 -05001997 ext_debug(" -> %u:%lu\n", lblock, len);
Theodore Ts'ob05e6ae2011-01-10 12:13:26 -05001998 ext4_ext_put_in_cache(inode, lblock, len, 0);
Alex Tomasa86c6182006-10-11 01:21:03 -07001999}
2000
Theodore Ts'ob05e6ae2011-01-10 12:13:26 -05002001/*
2002 * Return 0 if cache is invalid; 1 if the cache is valid
2003 */
Avantika Mathur09b88252006-12-06 20:41:36 -08002004static int
Aneesh Kumar K.V725d26d2008-01-28 23:58:27 -05002005ext4_ext_in_cache(struct inode *inode, ext4_lblk_t block,
Alex Tomasa86c6182006-10-11 01:21:03 -07002006 struct ext4_extent *ex)
2007{
2008 struct ext4_ext_cache *cex;
Theodore Ts'ob05e6ae2011-01-10 12:13:26 -05002009 int ret = 0;
Alex Tomasa86c6182006-10-11 01:21:03 -07002010
Theodore Ts'o60e66792010-05-17 07:00:00 -04002011 /*
Theodore Ts'o2ec0ae32009-05-15 09:07:28 -04002012 * We borrow i_block_reservation_lock to protect i_cached_extent
2013 */
2014 spin_lock(&EXT4_I(inode)->i_block_reservation_lock);
Alex Tomasa86c6182006-10-11 01:21:03 -07002015 cex = &EXT4_I(inode)->i_cached_extent;
2016
2017 /* has cache valid data? */
Theodore Ts'ob05e6ae2011-01-10 12:13:26 -05002018 if (cex->ec_len == 0)
Theodore Ts'o2ec0ae32009-05-15 09:07:28 -04002019 goto errout;
Alex Tomasa86c6182006-10-11 01:21:03 -07002020
Akinobu Mita731eb1a2010-03-03 23:55:01 -05002021 if (in_range(block, cex->ec_block, cex->ec_len)) {
Dave Kleikamp8c55e202007-05-24 13:04:54 -04002022 ex->ee_block = cpu_to_le32(cex->ec_block);
Alex Tomasf65e6fb2006-10-11 01:21:05 -07002023 ext4_ext_store_pblock(ex, cex->ec_start);
Dave Kleikamp8c55e202007-05-24 13:04:54 -04002024 ex->ee_len = cpu_to_le16(cex->ec_len);
Eric Sandeenbba90742008-01-28 23:58:27 -05002025 ext_debug("%u cached by %u:%u:%llu\n",
2026 block,
2027 cex->ec_block, cex->ec_len, cex->ec_start);
Theodore Ts'ob05e6ae2011-01-10 12:13:26 -05002028 ret = 1;
Alex Tomasa86c6182006-10-11 01:21:03 -07002029 }
Theodore Ts'o2ec0ae32009-05-15 09:07:28 -04002030errout:
2031 spin_unlock(&EXT4_I(inode)->i_block_reservation_lock);
2032 return ret;
Alex Tomasa86c6182006-10-11 01:21:03 -07002033}
2034
2035/*
Randy Dunlapd0d856e2006-10-11 01:21:07 -07002036 * ext4_ext_rm_idx:
2037 * removes index from the index block.
2038 * It's used in truncate case only, thus all requests are for
2039 * last index in the block only.
Alex Tomasa86c6182006-10-11 01:21:03 -07002040 */
Aneesh Kumar K.V1d03ec92008-01-28 23:58:27 -05002041static int ext4_ext_rm_idx(handle_t *handle, struct inode *inode,
Alex Tomasa86c6182006-10-11 01:21:03 -07002042 struct ext4_ext_path *path)
2043{
Alex Tomasa86c6182006-10-11 01:21:03 -07002044 int err;
Alex Tomasf65e6fb2006-10-11 01:21:05 -07002045 ext4_fsblk_t leaf;
Alex Tomasa86c6182006-10-11 01:21:03 -07002046
2047 /* free index block */
2048 path--;
Theodore Ts'obf89d162010-10-27 21:30:14 -04002049 leaf = ext4_idx_pblock(path->p_idx);
Frank Mayhar273df552010-03-02 11:46:09 -05002050 if (unlikely(path->p_hdr->eh_entries == 0)) {
2051 EXT4_ERROR_INODE(inode, "path->p_hdr->eh_entries == 0");
2052 return -EIO;
2053 }
Avantika Mathur7e028972006-12-06 20:41:33 -08002054 err = ext4_ext_get_access(handle, inode, path);
2055 if (err)
Alex Tomasa86c6182006-10-11 01:21:03 -07002056 return err;
Marcin Slusarze8546d02008-04-17 10:38:59 -04002057 le16_add_cpu(&path->p_hdr->eh_entries, -1);
Avantika Mathur7e028972006-12-06 20:41:33 -08002058 err = ext4_ext_dirty(handle, inode, path);
2059 if (err)
Alex Tomasa86c6182006-10-11 01:21:03 -07002060 return err;
Mingming Cao2ae02102006-10-11 01:21:11 -07002061 ext_debug("index is empty, remove it, free block %llu\n", leaf);
Theodore Ts'oe6362602009-11-23 07:17:05 -05002062 ext4_free_blocks(handle, inode, 0, leaf, 1,
2063 EXT4_FREE_BLOCKS_METADATA | EXT4_FREE_BLOCKS_FORGET);
Alex Tomasa86c6182006-10-11 01:21:03 -07002064 return err;
2065}
2066
2067/*
Mingming Caoee12b632008-08-19 22:16:05 -04002068 * ext4_ext_calc_credits_for_single_extent:
2069 * This routine returns max. credits that needed to insert an extent
2070 * to the extent tree.
2071 * When pass the actual path, the caller should calculate credits
2072 * under i_data_sem.
Alex Tomasa86c6182006-10-11 01:21:03 -07002073 */
Mingming Cao525f4ed2008-08-19 22:15:58 -04002074int ext4_ext_calc_credits_for_single_extent(struct inode *inode, int nrblocks,
Alex Tomasa86c6182006-10-11 01:21:03 -07002075 struct ext4_ext_path *path)
2076{
Alex Tomasa86c6182006-10-11 01:21:03 -07002077 if (path) {
Mingming Caoee12b632008-08-19 22:16:05 -04002078 int depth = ext_depth(inode);
Mingming Caof3bd1f32008-08-19 22:16:03 -04002079 int ret = 0;
Mingming Caoee12b632008-08-19 22:16:05 -04002080
Alex Tomasa86c6182006-10-11 01:21:03 -07002081 /* probably there is space in leaf? */
Alex Tomasa86c6182006-10-11 01:21:03 -07002082 if (le16_to_cpu(path[depth].p_hdr->eh_entries)
Mingming Caoee12b632008-08-19 22:16:05 -04002083 < le16_to_cpu(path[depth].p_hdr->eh_max)) {
2084
2085 /*
2086 * There are some space in the leaf tree, no
2087 * need to account for leaf block credit
2088 *
2089 * bitmaps and block group descriptor blocks
2090 * and other metadat blocks still need to be
2091 * accounted.
2092 */
Mingming Cao525f4ed2008-08-19 22:15:58 -04002093 /* 1 bitmap, 1 block group descriptor */
Mingming Caoee12b632008-08-19 22:16:05 -04002094 ret = 2 + EXT4_META_TRANS_BLOCKS(inode->i_sb);
Aneesh Kumar K.V5887e982009-07-05 23:12:04 -04002095 return ret;
Mingming Caoee12b632008-08-19 22:16:05 -04002096 }
Alex Tomasa86c6182006-10-11 01:21:03 -07002097 }
2098
Mingming Cao525f4ed2008-08-19 22:15:58 -04002099 return ext4_chunk_trans_blocks(inode, nrblocks);
Mingming Caoee12b632008-08-19 22:16:05 -04002100}
Alex Tomasa86c6182006-10-11 01:21:03 -07002101
Mingming Caoee12b632008-08-19 22:16:05 -04002102/*
2103 * How many index/leaf blocks need to change/allocate to modify nrblocks?
2104 *
2105 * if nrblocks are fit in a single extent (chunk flag is 1), then
2106 * in the worse case, each tree level index/leaf need to be changed
2107 * if the tree split due to insert a new extent, then the old tree
2108 * index/leaf need to be updated too
2109 *
2110 * If the nrblocks are discontiguous, they could cause
2111 * the whole tree split more than once, but this is really rare.
2112 */
Mingming Cao525f4ed2008-08-19 22:15:58 -04002113int ext4_ext_index_trans_blocks(struct inode *inode, int nrblocks, int chunk)
Mingming Caoee12b632008-08-19 22:16:05 -04002114{
2115 int index;
2116 int depth = ext_depth(inode);
Alex Tomasa86c6182006-10-11 01:21:03 -07002117
Mingming Caoee12b632008-08-19 22:16:05 -04002118 if (chunk)
2119 index = depth * 2;
2120 else
2121 index = depth * 3;
Alex Tomasa86c6182006-10-11 01:21:03 -07002122
Mingming Caoee12b632008-08-19 22:16:05 -04002123 return index;
Alex Tomasa86c6182006-10-11 01:21:03 -07002124}
2125
2126static int ext4_remove_blocks(handle_t *handle, struct inode *inode,
2127 struct ext4_extent *ex,
Aneesh Kumar K.V725d26d2008-01-28 23:58:27 -05002128 ext4_lblk_t from, ext4_lblk_t to)
Alex Tomasa86c6182006-10-11 01:21:03 -07002129{
Amit Aroraa2df2a62007-07-17 21:42:41 -04002130 unsigned short ee_len = ext4_ext_get_actual_len(ex);
Theodore Ts'oe6362602009-11-23 07:17:05 -05002131 int flags = EXT4_FREE_BLOCKS_FORGET;
Alex Tomasa86c6182006-10-11 01:21:03 -07002132
Alex Tomasc9de5602008-01-29 00:19:52 -05002133 if (S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode))
Theodore Ts'oe6362602009-11-23 07:17:05 -05002134 flags |= EXT4_FREE_BLOCKS_METADATA;
Alex Tomasa86c6182006-10-11 01:21:03 -07002135#ifdef EXTENTS_STATS
2136 {
2137 struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
Alex Tomasa86c6182006-10-11 01:21:03 -07002138 spin_lock(&sbi->s_ext_stats_lock);
2139 sbi->s_ext_blocks += ee_len;
2140 sbi->s_ext_extents++;
2141 if (ee_len < sbi->s_ext_min)
2142 sbi->s_ext_min = ee_len;
2143 if (ee_len > sbi->s_ext_max)
2144 sbi->s_ext_max = ee_len;
2145 if (ext_depth(inode) > sbi->s_depth_max)
2146 sbi->s_depth_max = ext_depth(inode);
2147 spin_unlock(&sbi->s_ext_stats_lock);
2148 }
2149#endif
2150 if (from >= le32_to_cpu(ex->ee_block)
Amit Aroraa2df2a62007-07-17 21:42:41 -04002151 && to == le32_to_cpu(ex->ee_block) + ee_len - 1) {
Alex Tomasa86c6182006-10-11 01:21:03 -07002152 /* tail removal */
Aneesh Kumar K.V725d26d2008-01-28 23:58:27 -05002153 ext4_lblk_t num;
Alex Tomasf65e6fb2006-10-11 01:21:05 -07002154 ext4_fsblk_t start;
Aneesh Kumar K.V725d26d2008-01-28 23:58:27 -05002155
Amit Aroraa2df2a62007-07-17 21:42:41 -04002156 num = le32_to_cpu(ex->ee_block) + ee_len - from;
Theodore Ts'obf89d162010-10-27 21:30:14 -04002157 start = ext4_ext_pblock(ex) + ee_len - num;
Aneesh Kumar K.V725d26d2008-01-28 23:58:27 -05002158 ext_debug("free last %u blocks starting %llu\n", num, start);
Theodore Ts'oe6362602009-11-23 07:17:05 -05002159 ext4_free_blocks(handle, inode, 0, start, num, flags);
Alex Tomasa86c6182006-10-11 01:21:03 -07002160 } else if (from == le32_to_cpu(ex->ee_block)
Amit Aroraa2df2a62007-07-17 21:42:41 -04002161 && to <= le32_to_cpu(ex->ee_block) + ee_len - 1) {
Aneesh Kumar K.V725d26d2008-01-28 23:58:27 -05002162 printk(KERN_INFO "strange request: removal %u-%u from %u:%u\n",
Amit Aroraa2df2a62007-07-17 21:42:41 -04002163 from, to, le32_to_cpu(ex->ee_block), ee_len);
Alex Tomasa86c6182006-10-11 01:21:03 -07002164 } else {
Aneesh Kumar K.V725d26d2008-01-28 23:58:27 -05002165 printk(KERN_INFO "strange request: removal(2) "
2166 "%u-%u from %u:%u\n",
2167 from, to, le32_to_cpu(ex->ee_block), ee_len);
Alex Tomasa86c6182006-10-11 01:21:03 -07002168 }
2169 return 0;
2170}
2171
2172static int
2173ext4_ext_rm_leaf(handle_t *handle, struct inode *inode,
Aneesh Kumar K.V725d26d2008-01-28 23:58:27 -05002174 struct ext4_ext_path *path, ext4_lblk_t start)
Alex Tomasa86c6182006-10-11 01:21:03 -07002175{
2176 int err = 0, correct_index = 0;
2177 int depth = ext_depth(inode), credits;
2178 struct ext4_extent_header *eh;
Aneesh Kumar K.V725d26d2008-01-28 23:58:27 -05002179 ext4_lblk_t a, b, block;
2180 unsigned num;
2181 ext4_lblk_t ex_ee_block;
Alex Tomasa86c6182006-10-11 01:21:03 -07002182 unsigned short ex_ee_len;
Amit Aroraa2df2a62007-07-17 21:42:41 -04002183 unsigned uninitialized = 0;
Alex Tomasa86c6182006-10-11 01:21:03 -07002184 struct ext4_extent *ex;
2185
Alex Tomasc29c0ae2007-07-18 09:19:09 -04002186 /* the header must be checked already in ext4_ext_remove_space() */
Aneesh Kumar K.V725d26d2008-01-28 23:58:27 -05002187 ext_debug("truncate since %u in leaf\n", start);
Alex Tomasa86c6182006-10-11 01:21:03 -07002188 if (!path[depth].p_hdr)
2189 path[depth].p_hdr = ext_block_hdr(path[depth].p_bh);
2190 eh = path[depth].p_hdr;
Frank Mayhar273df552010-03-02 11:46:09 -05002191 if (unlikely(path[depth].p_hdr == NULL)) {
2192 EXT4_ERROR_INODE(inode, "path[%d].p_hdr == NULL", depth);
2193 return -EIO;
2194 }
Alex Tomasa86c6182006-10-11 01:21:03 -07002195 /* find where to start removing */
2196 ex = EXT_LAST_EXTENT(eh);
2197
2198 ex_ee_block = le32_to_cpu(ex->ee_block);
Amit Aroraa2df2a62007-07-17 21:42:41 -04002199 ex_ee_len = ext4_ext_get_actual_len(ex);
Alex Tomasa86c6182006-10-11 01:21:03 -07002200
2201 while (ex >= EXT_FIRST_EXTENT(eh) &&
2202 ex_ee_block + ex_ee_len > start) {
Aneesh Kumar K.Va41f2072009-06-10 14:22:55 -04002203
2204 if (ext4_ext_is_uninitialized(ex))
2205 uninitialized = 1;
2206 else
2207 uninitialized = 0;
2208
Mingming553f9002009-09-18 13:34:55 -04002209 ext_debug("remove ext %u:[%d]%d\n", ex_ee_block,
2210 uninitialized, ex_ee_len);
Alex Tomasa86c6182006-10-11 01:21:03 -07002211 path[depth].p_ext = ex;
2212
2213 a = ex_ee_block > start ? ex_ee_block : start;
2214 b = ex_ee_block + ex_ee_len - 1 < EXT_MAX_BLOCK ?
2215 ex_ee_block + ex_ee_len - 1 : EXT_MAX_BLOCK;
2216
2217 ext_debug(" border %u:%u\n", a, b);
2218
2219 if (a != ex_ee_block && b != ex_ee_block + ex_ee_len - 1) {
2220 block = 0;
2221 num = 0;
2222 BUG();
2223 } else if (a != ex_ee_block) {
2224 /* remove tail of the extent */
2225 block = ex_ee_block;
2226 num = a - block;
2227 } else if (b != ex_ee_block + ex_ee_len - 1) {
2228 /* remove head of the extent */
2229 block = a;
2230 num = b - a;
2231 /* there is no "make a hole" API yet */
2232 BUG();
2233 } else {
2234 /* remove whole extent: excellent! */
2235 block = ex_ee_block;
2236 num = 0;
2237 BUG_ON(a != ex_ee_block);
2238 BUG_ON(b != ex_ee_block + ex_ee_len - 1);
2239 }
2240
Theodore Ts'o34071da2008-08-01 21:59:19 -04002241 /*
2242 * 3 for leaf, sb, and inode plus 2 (bmap and group
2243 * descriptor) for each block group; assume two block
2244 * groups plus ex_ee_len/blocks_per_block_group for
2245 * the worst case
2246 */
2247 credits = 7 + 2*(ex_ee_len/EXT4_BLOCKS_PER_GROUP(inode->i_sb));
Alex Tomasa86c6182006-10-11 01:21:03 -07002248 if (ex == EXT_FIRST_EXTENT(eh)) {
2249 correct_index = 1;
2250 credits += (ext_depth(inode)) + 1;
2251 }
Dmitry Monakhov5aca07e2009-12-08 22:42:15 -05002252 credits += EXT4_MAXQUOTAS_TRANS_BLOCKS(inode->i_sb);
Alex Tomasa86c6182006-10-11 01:21:03 -07002253
Jan Kara487caee2009-08-17 22:17:20 -04002254 err = ext4_ext_truncate_extend_restart(handle, inode, credits);
Shen Feng9102e4f2008-07-11 19:27:31 -04002255 if (err)
Alex Tomasa86c6182006-10-11 01:21:03 -07002256 goto out;
Alex Tomasa86c6182006-10-11 01:21:03 -07002257
2258 err = ext4_ext_get_access(handle, inode, path + depth);
2259 if (err)
2260 goto out;
2261
2262 err = ext4_remove_blocks(handle, inode, ex, a, b);
2263 if (err)
2264 goto out;
2265
2266 if (num == 0) {
Randy Dunlapd0d856e2006-10-11 01:21:07 -07002267 /* this extent is removed; mark slot entirely unused */
Alex Tomasf65e6fb2006-10-11 01:21:05 -07002268 ext4_ext_store_pblock(ex, 0);
Marcin Slusarze8546d02008-04-17 10:38:59 -04002269 le16_add_cpu(&eh->eh_entries, -1);
Alex Tomasa86c6182006-10-11 01:21:03 -07002270 }
2271
2272 ex->ee_block = cpu_to_le32(block);
2273 ex->ee_len = cpu_to_le16(num);
Amit Arora749269f2007-07-18 09:02:56 -04002274 /*
2275 * Do not mark uninitialized if all the blocks in the
2276 * extent have been removed.
2277 */
2278 if (uninitialized && num)
Amit Aroraa2df2a62007-07-17 21:42:41 -04002279 ext4_ext_mark_uninitialized(ex);
Alex Tomasa86c6182006-10-11 01:21:03 -07002280
2281 err = ext4_ext_dirty(handle, inode, path + depth);
2282 if (err)
2283 goto out;
2284
Mingming Cao2ae02102006-10-11 01:21:11 -07002285 ext_debug("new extent: %u:%u:%llu\n", block, num,
Theodore Ts'obf89d162010-10-27 21:30:14 -04002286 ext4_ext_pblock(ex));
Alex Tomasa86c6182006-10-11 01:21:03 -07002287 ex--;
2288 ex_ee_block = le32_to_cpu(ex->ee_block);
Amit Aroraa2df2a62007-07-17 21:42:41 -04002289 ex_ee_len = ext4_ext_get_actual_len(ex);
Alex Tomasa86c6182006-10-11 01:21:03 -07002290 }
2291
2292 if (correct_index && eh->eh_entries)
2293 err = ext4_ext_correct_indexes(handle, inode, path);
2294
2295 /* if this leaf is free, then we should
2296 * remove it from index block above */
2297 if (err == 0 && eh->eh_entries == 0 && path[depth].p_bh != NULL)
2298 err = ext4_ext_rm_idx(handle, inode, path + depth);
2299
2300out:
2301 return err;
2302}
2303
2304/*
Randy Dunlapd0d856e2006-10-11 01:21:07 -07002305 * ext4_ext_more_to_rm:
2306 * returns 1 if current index has to be freed (even partial)
Alex Tomasa86c6182006-10-11 01:21:03 -07002307 */
Avantika Mathur09b88252006-12-06 20:41:36 -08002308static int
Alex Tomasa86c6182006-10-11 01:21:03 -07002309ext4_ext_more_to_rm(struct ext4_ext_path *path)
2310{
2311 BUG_ON(path->p_idx == NULL);
2312
2313 if (path->p_idx < EXT_FIRST_INDEX(path->p_hdr))
2314 return 0;
2315
2316 /*
Randy Dunlapd0d856e2006-10-11 01:21:07 -07002317 * if truncate on deeper level happened, it wasn't partial,
Alex Tomasa86c6182006-10-11 01:21:03 -07002318 * so we have to consider current index for truncation
2319 */
2320 if (le16_to_cpu(path->p_hdr->eh_entries) == path->p_block)
2321 return 0;
2322 return 1;
2323}
2324
Aneesh Kumar K.V1d03ec92008-01-28 23:58:27 -05002325static int ext4_ext_remove_space(struct inode *inode, ext4_lblk_t start)
Alex Tomasa86c6182006-10-11 01:21:03 -07002326{
2327 struct super_block *sb = inode->i_sb;
2328 int depth = ext_depth(inode);
2329 struct ext4_ext_path *path;
2330 handle_t *handle;
Dmitry Monakhov0617b832010-05-17 01:00:00 -04002331 int i, err;
Alex Tomasa86c6182006-10-11 01:21:03 -07002332
Aneesh Kumar K.V725d26d2008-01-28 23:58:27 -05002333 ext_debug("truncate since %u\n", start);
Alex Tomasa86c6182006-10-11 01:21:03 -07002334
2335 /* probably first extent we're gonna free will be last in block */
2336 handle = ext4_journal_start(inode, depth + 1);
2337 if (IS_ERR(handle))
2338 return PTR_ERR(handle);
2339
Dmitry Monakhov0617b832010-05-17 01:00:00 -04002340again:
Alex Tomasa86c6182006-10-11 01:21:03 -07002341 ext4_ext_invalidate_cache(inode);
2342
2343 /*
Randy Dunlapd0d856e2006-10-11 01:21:07 -07002344 * We start scanning from right side, freeing all the blocks
2345 * after i_size and walking into the tree depth-wise.
Alex Tomasa86c6182006-10-11 01:21:03 -07002346 */
Dmitry Monakhov0617b832010-05-17 01:00:00 -04002347 depth = ext_depth(inode);
Josef Bacik216553c2008-04-29 22:02:02 -04002348 path = kzalloc(sizeof(struct ext4_ext_path) * (depth + 1), GFP_NOFS);
Alex Tomasa86c6182006-10-11 01:21:03 -07002349 if (path == NULL) {
2350 ext4_journal_stop(handle);
2351 return -ENOMEM;
2352 }
Dmitry Monakhov0617b832010-05-17 01:00:00 -04002353 path[0].p_depth = depth;
Alex Tomasa86c6182006-10-11 01:21:03 -07002354 path[0].p_hdr = ext_inode_hdr(inode);
Aneesh Kumar K.V56b19862009-03-12 09:51:20 -04002355 if (ext4_ext_check(inode, path[0].p_hdr, depth)) {
Alex Tomasa86c6182006-10-11 01:21:03 -07002356 err = -EIO;
2357 goto out;
2358 }
Dmitry Monakhov0617b832010-05-17 01:00:00 -04002359 i = err = 0;
Alex Tomasa86c6182006-10-11 01:21:03 -07002360
2361 while (i >= 0 && err == 0) {
2362 if (i == depth) {
2363 /* this is leaf block */
2364 err = ext4_ext_rm_leaf(handle, inode, path, start);
Randy Dunlapd0d856e2006-10-11 01:21:07 -07002365 /* root level has p_bh == NULL, brelse() eats this */
Alex Tomasa86c6182006-10-11 01:21:03 -07002366 brelse(path[i].p_bh);
2367 path[i].p_bh = NULL;
2368 i--;
2369 continue;
2370 }
2371
2372 /* this is index block */
2373 if (!path[i].p_hdr) {
2374 ext_debug("initialize header\n");
2375 path[i].p_hdr = ext_block_hdr(path[i].p_bh);
Alex Tomasa86c6182006-10-11 01:21:03 -07002376 }
2377
Alex Tomasa86c6182006-10-11 01:21:03 -07002378 if (!path[i].p_idx) {
Randy Dunlapd0d856e2006-10-11 01:21:07 -07002379 /* this level hasn't been touched yet */
Alex Tomasa86c6182006-10-11 01:21:03 -07002380 path[i].p_idx = EXT_LAST_INDEX(path[i].p_hdr);
2381 path[i].p_block = le16_to_cpu(path[i].p_hdr->eh_entries)+1;
2382 ext_debug("init index ptr: hdr 0x%p, num %d\n",
2383 path[i].p_hdr,
2384 le16_to_cpu(path[i].p_hdr->eh_entries));
2385 } else {
Randy Dunlapd0d856e2006-10-11 01:21:07 -07002386 /* we were already here, see at next index */
Alex Tomasa86c6182006-10-11 01:21:03 -07002387 path[i].p_idx--;
2388 }
2389
2390 ext_debug("level %d - index, first 0x%p, cur 0x%p\n",
2391 i, EXT_FIRST_INDEX(path[i].p_hdr),
2392 path[i].p_idx);
2393 if (ext4_ext_more_to_rm(path + i)) {
Alex Tomasc29c0ae2007-07-18 09:19:09 -04002394 struct buffer_head *bh;
Alex Tomasa86c6182006-10-11 01:21:03 -07002395 /* go to the next level */
Mingming Cao2ae02102006-10-11 01:21:11 -07002396 ext_debug("move to level %d (block %llu)\n",
Theodore Ts'obf89d162010-10-27 21:30:14 -04002397 i + 1, ext4_idx_pblock(path[i].p_idx));
Alex Tomasa86c6182006-10-11 01:21:03 -07002398 memset(path + i + 1, 0, sizeof(*path));
Theodore Ts'obf89d162010-10-27 21:30:14 -04002399 bh = sb_bread(sb, ext4_idx_pblock(path[i].p_idx));
Alex Tomasc29c0ae2007-07-18 09:19:09 -04002400 if (!bh) {
Alex Tomasa86c6182006-10-11 01:21:03 -07002401 /* should we reset i_size? */
2402 err = -EIO;
2403 break;
2404 }
Alex Tomasc29c0ae2007-07-18 09:19:09 -04002405 if (WARN_ON(i + 1 > depth)) {
2406 err = -EIO;
2407 break;
2408 }
Aneesh Kumar K.V56b19862009-03-12 09:51:20 -04002409 if (ext4_ext_check(inode, ext_block_hdr(bh),
Alex Tomasc29c0ae2007-07-18 09:19:09 -04002410 depth - i - 1)) {
2411 err = -EIO;
2412 break;
2413 }
2414 path[i + 1].p_bh = bh;
Alex Tomasa86c6182006-10-11 01:21:03 -07002415
Randy Dunlapd0d856e2006-10-11 01:21:07 -07002416 /* save actual number of indexes since this
2417 * number is changed at the next iteration */
Alex Tomasa86c6182006-10-11 01:21:03 -07002418 path[i].p_block = le16_to_cpu(path[i].p_hdr->eh_entries);
2419 i++;
2420 } else {
Randy Dunlapd0d856e2006-10-11 01:21:07 -07002421 /* we finished processing this index, go up */
Alex Tomasa86c6182006-10-11 01:21:03 -07002422 if (path[i].p_hdr->eh_entries == 0 && i > 0) {
Randy Dunlapd0d856e2006-10-11 01:21:07 -07002423 /* index is empty, remove it;
Alex Tomasa86c6182006-10-11 01:21:03 -07002424 * handle must be already prepared by the
2425 * truncatei_leaf() */
2426 err = ext4_ext_rm_idx(handle, inode, path + i);
2427 }
Randy Dunlapd0d856e2006-10-11 01:21:07 -07002428 /* root level has p_bh == NULL, brelse() eats this */
Alex Tomasa86c6182006-10-11 01:21:03 -07002429 brelse(path[i].p_bh);
2430 path[i].p_bh = NULL;
2431 i--;
2432 ext_debug("return to level %d\n", i);
2433 }
2434 }
2435
2436 /* TODO: flexible tree reduction should be here */
2437 if (path->p_hdr->eh_entries == 0) {
2438 /*
Randy Dunlapd0d856e2006-10-11 01:21:07 -07002439 * truncate to zero freed all the tree,
2440 * so we need to correct eh_depth
Alex Tomasa86c6182006-10-11 01:21:03 -07002441 */
2442 err = ext4_ext_get_access(handle, inode, path);
2443 if (err == 0) {
2444 ext_inode_hdr(inode)->eh_depth = 0;
2445 ext_inode_hdr(inode)->eh_max =
Theodore Ts'o55ad63b2009-08-28 10:40:33 -04002446 cpu_to_le16(ext4_ext_space_root(inode, 0));
Alex Tomasa86c6182006-10-11 01:21:03 -07002447 err = ext4_ext_dirty(handle, inode, path);
2448 }
2449 }
2450out:
Alex Tomasa86c6182006-10-11 01:21:03 -07002451 ext4_ext_drop_refs(path);
2452 kfree(path);
Dmitry Monakhov0617b832010-05-17 01:00:00 -04002453 if (err == -EAGAIN)
2454 goto again;
Alex Tomasa86c6182006-10-11 01:21:03 -07002455 ext4_journal_stop(handle);
2456
2457 return err;
2458}
2459
2460/*
2461 * called at mount time
2462 */
2463void ext4_ext_init(struct super_block *sb)
2464{
2465 /*
2466 * possible initialization would be here
2467 */
2468
Theodore Ts'o83982b62009-01-06 14:53:16 -05002469 if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_EXTENTS)) {
Theodore Ts'o90576c02009-09-29 15:51:30 -04002470#if defined(AGGRESSIVE_TEST) || defined(CHECK_BINSEARCH) || defined(EXTENTS_STATS)
Theodore Ts'o4776004f2008-09-08 23:00:52 -04002471 printk(KERN_INFO "EXT4-fs: file extents enabled");
Robert P. J. Daybbf2f9f2007-02-17 19:20:16 +01002472#ifdef AGGRESSIVE_TEST
2473 printk(", aggressive tests");
Alex Tomasa86c6182006-10-11 01:21:03 -07002474#endif
2475#ifdef CHECK_BINSEARCH
2476 printk(", check binsearch");
2477#endif
2478#ifdef EXTENTS_STATS
2479 printk(", stats");
2480#endif
2481 printk("\n");
Theodore Ts'o90576c02009-09-29 15:51:30 -04002482#endif
Alex Tomasa86c6182006-10-11 01:21:03 -07002483#ifdef EXTENTS_STATS
2484 spin_lock_init(&EXT4_SB(sb)->s_ext_stats_lock);
2485 EXT4_SB(sb)->s_ext_min = 1 << 30;
2486 EXT4_SB(sb)->s_ext_max = 0;
2487#endif
2488 }
2489}
2490
2491/*
2492 * called at umount time
2493 */
2494void ext4_ext_release(struct super_block *sb)
2495{
Theodore Ts'o83982b62009-01-06 14:53:16 -05002496 if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_EXTENTS))
Alex Tomasa86c6182006-10-11 01:21:03 -07002497 return;
2498
2499#ifdef EXTENTS_STATS
2500 if (EXT4_SB(sb)->s_ext_blocks && EXT4_SB(sb)->s_ext_extents) {
2501 struct ext4_sb_info *sbi = EXT4_SB(sb);
2502 printk(KERN_ERR "EXT4-fs: %lu blocks in %lu extents (%lu ave)\n",
2503 sbi->s_ext_blocks, sbi->s_ext_extents,
2504 sbi->s_ext_blocks / sbi->s_ext_extents);
2505 printk(KERN_ERR "EXT4-fs: extents: %lu min, %lu max, max depth %lu\n",
2506 sbi->s_ext_min, sbi->s_ext_max, sbi->s_depth_max);
2507 }
2508#endif
2509}
2510
Aneesh Kumar K.V093a0882008-04-29 08:11:12 -04002511/* FIXME!! we need to try to merge to left or right after zero-out */
2512static int ext4_ext_zeroout(struct inode *inode, struct ext4_extent *ex)
2513{
Lukas Czerner24075182010-10-27 21:30:06 -04002514 ext4_fsblk_t ee_pblock;
2515 unsigned int ee_len;
Jing Zhangb7203032010-05-12 00:00:00 -04002516 int ret;
Aneesh Kumar K.V093a0882008-04-29 08:11:12 -04002517
Aneesh Kumar K.V093a0882008-04-29 08:11:12 -04002518 ee_len = ext4_ext_get_actual_len(ex);
Theodore Ts'obf89d162010-10-27 21:30:14 -04002519 ee_pblock = ext4_ext_pblock(ex);
Aneesh Kumar K.V093a0882008-04-29 08:11:12 -04002520
Theodore Ts'oa107e5a2010-10-27 23:44:47 -04002521 ret = sb_issue_zeroout(inode->i_sb, ee_pblock, ee_len, GFP_NOFS);
Lukas Czerner24075182010-10-27 21:30:06 -04002522 if (ret > 0)
2523 ret = 0;
Aneesh Kumar K.V093a0882008-04-29 08:11:12 -04002524
Lukas Czerner24075182010-10-27 21:30:06 -04002525 return ret;
Aneesh Kumar K.V093a0882008-04-29 08:11:12 -04002526}
2527
Aneesh Kumar K.V3977c962008-04-17 10:38:59 -04002528#define EXT4_EXT_ZERO_LEN 7
Amit Arora56055d32007-07-17 21:42:38 -04002529/*
Theodore Ts'oe35fd662010-05-16 19:00:00 -04002530 * This function is called by ext4_ext_map_blocks() if someone tries to write
Amit Arora56055d32007-07-17 21:42:38 -04002531 * to an uninitialized extent. It may result in splitting the uninitialized
2532 * extent into multiple extents (upto three - one initialized and two
2533 * uninitialized).
2534 * There are three possibilities:
2535 * a> There is no split required: Entire extent should be initialized
2536 * b> Splits in two extents: Write is happening at either end of the extent
2537 * c> Splits in three extents: Somone is writing in middle of the extent
2538 */
Aneesh Kumar K.V725d26d2008-01-28 23:58:27 -05002539static int ext4_ext_convert_to_initialized(handle_t *handle,
Theodore Ts'oe35fd662010-05-16 19:00:00 -04002540 struct inode *inode,
2541 struct ext4_map_blocks *map,
2542 struct ext4_ext_path *path)
Amit Arora56055d32007-07-17 21:42:38 -04002543{
Aneesh Kumar K.V95c38892008-04-17 10:38:59 -04002544 struct ext4_extent *ex, newex, orig_ex;
Amit Arora56055d32007-07-17 21:42:38 -04002545 struct ext4_extent *ex1 = NULL;
2546 struct ext4_extent *ex2 = NULL;
2547 struct ext4_extent *ex3 = NULL;
2548 struct ext4_extent_header *eh;
Dmitry Monakhov21ca0872010-05-16 06:00:00 -04002549 ext4_lblk_t ee_block, eof_block;
Aneesh Kumar K.V725d26d2008-01-28 23:58:27 -05002550 unsigned int allocated, ee_len, depth;
Amit Arora56055d32007-07-17 21:42:38 -04002551 ext4_fsblk_t newblock;
2552 int err = 0;
2553 int ret = 0;
Dmitry Monakhov21ca0872010-05-16 06:00:00 -04002554 int may_zeroout;
2555
2556 ext_debug("ext4_ext_convert_to_initialized: inode %lu, logical"
2557 "block %llu, max_blocks %u\n", inode->i_ino,
Theodore Ts'oe35fd662010-05-16 19:00:00 -04002558 (unsigned long long)map->m_lblk, map->m_len);
Dmitry Monakhov21ca0872010-05-16 06:00:00 -04002559
2560 eof_block = (inode->i_size + inode->i_sb->s_blocksize - 1) >>
2561 inode->i_sb->s_blocksize_bits;
Theodore Ts'oe35fd662010-05-16 19:00:00 -04002562 if (eof_block < map->m_lblk + map->m_len)
2563 eof_block = map->m_lblk + map->m_len;
Amit Arora56055d32007-07-17 21:42:38 -04002564
2565 depth = ext_depth(inode);
2566 eh = path[depth].p_hdr;
2567 ex = path[depth].p_ext;
2568 ee_block = le32_to_cpu(ex->ee_block);
2569 ee_len = ext4_ext_get_actual_len(ex);
Theodore Ts'oe35fd662010-05-16 19:00:00 -04002570 allocated = ee_len - (map->m_lblk - ee_block);
Theodore Ts'obf89d162010-10-27 21:30:14 -04002571 newblock = map->m_lblk - ee_block + ext4_ext_pblock(ex);
Dmitry Monakhov21ca0872010-05-16 06:00:00 -04002572
Amit Arora56055d32007-07-17 21:42:38 -04002573 ex2 = ex;
Aneesh Kumar K.V95c38892008-04-17 10:38:59 -04002574 orig_ex.ee_block = ex->ee_block;
2575 orig_ex.ee_len = cpu_to_le16(ee_len);
Theodore Ts'obf89d162010-10-27 21:30:14 -04002576 ext4_ext_store_pblock(&orig_ex, ext4_ext_pblock(ex));
Amit Arora56055d32007-07-17 21:42:38 -04002577
Dmitry Monakhov21ca0872010-05-16 06:00:00 -04002578 /*
2579 * It is safe to convert extent to initialized via explicit
2580 * zeroout only if extent is fully insde i_size or new_size.
2581 */
2582 may_zeroout = ee_block + ee_len <= eof_block;
2583
Aneesh Kumar K.V9df56432008-02-22 06:17:31 -05002584 err = ext4_ext_get_access(handle, inode, path + depth);
2585 if (err)
2586 goto out;
Aneesh Kumar K.V3977c962008-04-17 10:38:59 -04002587 /* If extent has less than 2*EXT4_EXT_ZERO_LEN zerout directly */
Dmitry Monakhov21ca0872010-05-16 06:00:00 -04002588 if (ee_len <= 2*EXT4_EXT_ZERO_LEN && may_zeroout) {
Aneesh Kumar K.V3977c962008-04-17 10:38:59 -04002589 err = ext4_ext_zeroout(inode, &orig_ex);
2590 if (err)
2591 goto fix_extent_len;
2592 /* update the extent length and mark as initialized */
2593 ex->ee_block = orig_ex.ee_block;
2594 ex->ee_len = orig_ex.ee_len;
Theodore Ts'obf89d162010-10-27 21:30:14 -04002595 ext4_ext_store_pblock(ex, ext4_ext_pblock(&orig_ex));
Aneesh Kumar K.V3977c962008-04-17 10:38:59 -04002596 ext4_ext_dirty(handle, inode, path + depth);
Aneesh Kumar K.V161e7b72008-04-29 22:03:59 -04002597 /* zeroed the full extent */
2598 return allocated;
Aneesh Kumar K.V3977c962008-04-17 10:38:59 -04002599 }
Aneesh Kumar K.V9df56432008-02-22 06:17:31 -05002600
Theodore Ts'oe35fd662010-05-16 19:00:00 -04002601 /* ex1: ee_block to map->m_lblk - 1 : uninitialized */
2602 if (map->m_lblk > ee_block) {
Amit Arora56055d32007-07-17 21:42:38 -04002603 ex1 = ex;
Theodore Ts'oe35fd662010-05-16 19:00:00 -04002604 ex1->ee_len = cpu_to_le16(map->m_lblk - ee_block);
Amit Arora56055d32007-07-17 21:42:38 -04002605 ext4_ext_mark_uninitialized(ex1);
2606 ex2 = &newex;
2607 }
2608 /*
2609 * for sanity, update the length of the ex2 extent before
2610 * we insert ex3, if ex1 is NULL. This is to avoid temporary
2611 * overlap of blocks.
2612 */
Theodore Ts'oe35fd662010-05-16 19:00:00 -04002613 if (!ex1 && allocated > map->m_len)
2614 ex2->ee_len = cpu_to_le16(map->m_len);
Amit Arora56055d32007-07-17 21:42:38 -04002615 /* ex3: to ee_block + ee_len : uninitialised */
Theodore Ts'oe35fd662010-05-16 19:00:00 -04002616 if (allocated > map->m_len) {
Amit Arora56055d32007-07-17 21:42:38 -04002617 unsigned int newdepth;
Aneesh Kumar K.V3977c962008-04-17 10:38:59 -04002618 /* If extent has less than EXT4_EXT_ZERO_LEN zerout directly */
Dmitry Monakhov21ca0872010-05-16 06:00:00 -04002619 if (allocated <= EXT4_EXT_ZERO_LEN && may_zeroout) {
Aneesh Kumar K.Vd03856b2008-08-02 18:51:32 -04002620 /*
Theodore Ts'oe35fd662010-05-16 19:00:00 -04002621 * map->m_lblk == ee_block is handled by the zerouout
Aneesh Kumar K.Vd03856b2008-08-02 18:51:32 -04002622 * at the beginning.
2623 * Mark first half uninitialized.
Aneesh Kumar K.V3977c962008-04-17 10:38:59 -04002624 * Mark second half initialized and zero out the
2625 * initialized extent
2626 */
2627 ex->ee_block = orig_ex.ee_block;
2628 ex->ee_len = cpu_to_le16(ee_len - allocated);
2629 ext4_ext_mark_uninitialized(ex);
Theodore Ts'obf89d162010-10-27 21:30:14 -04002630 ext4_ext_store_pblock(ex, ext4_ext_pblock(&orig_ex));
Aneesh Kumar K.V3977c962008-04-17 10:38:59 -04002631 ext4_ext_dirty(handle, inode, path + depth);
2632
2633 ex3 = &newex;
Theodore Ts'oe35fd662010-05-16 19:00:00 -04002634 ex3->ee_block = cpu_to_le32(map->m_lblk);
Aneesh Kumar K.V3977c962008-04-17 10:38:59 -04002635 ext4_ext_store_pblock(ex3, newblock);
2636 ex3->ee_len = cpu_to_le16(allocated);
Mingming Cao00314622009-09-28 15:49:08 -04002637 err = ext4_ext_insert_extent(handle, inode, path,
2638 ex3, 0);
Aneesh Kumar K.V3977c962008-04-17 10:38:59 -04002639 if (err == -ENOSPC) {
2640 err = ext4_ext_zeroout(inode, &orig_ex);
2641 if (err)
2642 goto fix_extent_len;
2643 ex->ee_block = orig_ex.ee_block;
2644 ex->ee_len = orig_ex.ee_len;
Theodore Ts'obf89d162010-10-27 21:30:14 -04002645 ext4_ext_store_pblock(ex,
2646 ext4_ext_pblock(&orig_ex));
Aneesh Kumar K.V3977c962008-04-17 10:38:59 -04002647 ext4_ext_dirty(handle, inode, path + depth);
Theodore Ts'oe35fd662010-05-16 19:00:00 -04002648 /* blocks available from map->m_lblk */
Aneesh Kumar K.V161e7b72008-04-29 22:03:59 -04002649 return allocated;
Aneesh Kumar K.V3977c962008-04-17 10:38:59 -04002650
2651 } else if (err)
2652 goto fix_extent_len;
2653
Aneesh Kumar K.V161e7b72008-04-29 22:03:59 -04002654 /*
2655 * We need to zero out the second half because
2656 * an fallocate request can update file size and
2657 * converting the second half to initialized extent
2658 * implies that we can leak some junk data to user
2659 * space.
2660 */
2661 err = ext4_ext_zeroout(inode, ex3);
2662 if (err) {
2663 /*
2664 * We should actually mark the
2665 * second half as uninit and return error
2666 * Insert would have changed the extent
2667 */
2668 depth = ext_depth(inode);
2669 ext4_ext_drop_refs(path);
Theodore Ts'oe35fd662010-05-16 19:00:00 -04002670 path = ext4_ext_find_extent(inode, map->m_lblk,
2671 path);
Aneesh Kumar K.V161e7b72008-04-29 22:03:59 -04002672 if (IS_ERR(path)) {
2673 err = PTR_ERR(path);
2674 return err;
2675 }
Aneesh Kumar K.Vd03856b2008-08-02 18:51:32 -04002676 /* get the second half extent details */
Aneesh Kumar K.V161e7b72008-04-29 22:03:59 -04002677 ex = path[depth].p_ext;
2678 err = ext4_ext_get_access(handle, inode,
2679 path + depth);
2680 if (err)
2681 return err;
2682 ext4_ext_mark_uninitialized(ex);
2683 ext4_ext_dirty(handle, inode, path + depth);
2684 return err;
2685 }
2686
2687 /* zeroed the second half */
Aneesh Kumar K.V3977c962008-04-17 10:38:59 -04002688 return allocated;
2689 }
Amit Arora56055d32007-07-17 21:42:38 -04002690 ex3 = &newex;
Theodore Ts'oe35fd662010-05-16 19:00:00 -04002691 ex3->ee_block = cpu_to_le32(map->m_lblk + map->m_len);
2692 ext4_ext_store_pblock(ex3, newblock + map->m_len);
2693 ex3->ee_len = cpu_to_le16(allocated - map->m_len);
Amit Arora56055d32007-07-17 21:42:38 -04002694 ext4_ext_mark_uninitialized(ex3);
Mingming Cao00314622009-09-28 15:49:08 -04002695 err = ext4_ext_insert_extent(handle, inode, path, ex3, 0);
Dmitry Monakhov21ca0872010-05-16 06:00:00 -04002696 if (err == -ENOSPC && may_zeroout) {
Aneesh Kumar K.V093a0882008-04-29 08:11:12 -04002697 err = ext4_ext_zeroout(inode, &orig_ex);
2698 if (err)
2699 goto fix_extent_len;
2700 /* update the extent length and mark as initialized */
Aneesh Kumar K.V95c38892008-04-17 10:38:59 -04002701 ex->ee_block = orig_ex.ee_block;
2702 ex->ee_len = orig_ex.ee_len;
Theodore Ts'obf89d162010-10-27 21:30:14 -04002703 ext4_ext_store_pblock(ex, ext4_ext_pblock(&orig_ex));
Aneesh Kumar K.V95c38892008-04-17 10:38:59 -04002704 ext4_ext_dirty(handle, inode, path + depth);
Aneesh Kumar K.V161e7b72008-04-29 22:03:59 -04002705 /* zeroed the full extent */
Theodore Ts'oe35fd662010-05-16 19:00:00 -04002706 /* blocks available from map->m_lblk */
Aneesh Kumar K.V161e7b72008-04-29 22:03:59 -04002707 return allocated;
Aneesh Kumar K.V093a0882008-04-29 08:11:12 -04002708
2709 } else if (err)
2710 goto fix_extent_len;
Amit Arora56055d32007-07-17 21:42:38 -04002711 /*
2712 * The depth, and hence eh & ex might change
2713 * as part of the insert above.
2714 */
2715 newdepth = ext_depth(inode);
Aneesh Kumar K.V95c38892008-04-17 10:38:59 -04002716 /*
Coly Li73ac36e2009-01-07 18:09:16 -08002717 * update the extent length after successful insert of the
Aneesh Kumar K.V95c38892008-04-17 10:38:59 -04002718 * split extent
2719 */
Dmitry Monakhov21ca0872010-05-16 06:00:00 -04002720 ee_len -= ext4_ext_get_actual_len(ex3);
2721 orig_ex.ee_len = cpu_to_le16(ee_len);
2722 may_zeroout = ee_block + ee_len <= eof_block;
2723
Aneesh Kumar K.Vd03856b2008-08-02 18:51:32 -04002724 depth = newdepth;
2725 ext4_ext_drop_refs(path);
Theodore Ts'oe35fd662010-05-16 19:00:00 -04002726 path = ext4_ext_find_extent(inode, map->m_lblk, path);
Aneesh Kumar K.Vd03856b2008-08-02 18:51:32 -04002727 if (IS_ERR(path)) {
2728 err = PTR_ERR(path);
2729 goto out;
Amit Arora56055d32007-07-17 21:42:38 -04002730 }
Aneesh Kumar K.Vd03856b2008-08-02 18:51:32 -04002731 eh = path[depth].p_hdr;
2732 ex = path[depth].p_ext;
2733 if (ex2 != &newex)
2734 ex2 = ex;
2735
2736 err = ext4_ext_get_access(handle, inode, path + depth);
2737 if (err)
2738 goto out;
2739
Theodore Ts'oe35fd662010-05-16 19:00:00 -04002740 allocated = map->m_len;
Aneesh Kumar K.V3977c962008-04-17 10:38:59 -04002741
2742 /* If extent has less than EXT4_EXT_ZERO_LEN and we are trying
2743 * to insert a extent in the middle zerout directly
2744 * otherwise give the extent a chance to merge to left
2745 */
2746 if (le16_to_cpu(orig_ex.ee_len) <= EXT4_EXT_ZERO_LEN &&
Theodore Ts'oe35fd662010-05-16 19:00:00 -04002747 map->m_lblk != ee_block && may_zeroout) {
Aneesh Kumar K.V3977c962008-04-17 10:38:59 -04002748 err = ext4_ext_zeroout(inode, &orig_ex);
2749 if (err)
2750 goto fix_extent_len;
2751 /* update the extent length and mark as initialized */
2752 ex->ee_block = orig_ex.ee_block;
2753 ex->ee_len = orig_ex.ee_len;
Theodore Ts'obf89d162010-10-27 21:30:14 -04002754 ext4_ext_store_pblock(ex, ext4_ext_pblock(&orig_ex));
Aneesh Kumar K.V3977c962008-04-17 10:38:59 -04002755 ext4_ext_dirty(handle, inode, path + depth);
Aneesh Kumar K.V161e7b72008-04-29 22:03:59 -04002756 /* zero out the first half */
Theodore Ts'oe35fd662010-05-16 19:00:00 -04002757 /* blocks available from map->m_lblk */
Aneesh Kumar K.V161e7b72008-04-29 22:03:59 -04002758 return allocated;
Aneesh Kumar K.V3977c962008-04-17 10:38:59 -04002759 }
Amit Arora56055d32007-07-17 21:42:38 -04002760 }
2761 /*
2762 * If there was a change of depth as part of the
2763 * insertion of ex3 above, we need to update the length
2764 * of the ex1 extent again here
2765 */
2766 if (ex1 && ex1 != ex) {
2767 ex1 = ex;
Theodore Ts'oe35fd662010-05-16 19:00:00 -04002768 ex1->ee_len = cpu_to_le16(map->m_lblk - ee_block);
Amit Arora56055d32007-07-17 21:42:38 -04002769 ext4_ext_mark_uninitialized(ex1);
2770 ex2 = &newex;
2771 }
Theodore Ts'oe35fd662010-05-16 19:00:00 -04002772 /* ex2: map->m_lblk to map->m_lblk + maxblocks-1 : initialised */
2773 ex2->ee_block = cpu_to_le32(map->m_lblk);
Amit Arora56055d32007-07-17 21:42:38 -04002774 ext4_ext_store_pblock(ex2, newblock);
2775 ex2->ee_len = cpu_to_le16(allocated);
2776 if (ex2 != ex)
2777 goto insert;
Amit Arora56055d32007-07-17 21:42:38 -04002778 /*
2779 * New (initialized) extent starts from the first block
2780 * in the current extent. i.e., ex2 == ex
2781 * We have to see if it can be merged with the extent
2782 * on the left.
2783 */
2784 if (ex2 > EXT_FIRST_EXTENT(eh)) {
2785 /*
2786 * To merge left, pass "ex2 - 1" to try_to_merge(),
2787 * since it merges towards right _only_.
2788 */
2789 ret = ext4_ext_try_to_merge(inode, path, ex2 - 1);
2790 if (ret) {
2791 err = ext4_ext_correct_indexes(handle, inode, path);
2792 if (err)
2793 goto out;
2794 depth = ext_depth(inode);
2795 ex2--;
2796 }
2797 }
2798 /*
2799 * Try to Merge towards right. This might be required
2800 * only when the whole extent is being written to.
2801 * i.e. ex2 == ex and ex3 == NULL.
2802 */
2803 if (!ex3) {
2804 ret = ext4_ext_try_to_merge(inode, path, ex2);
2805 if (ret) {
2806 err = ext4_ext_correct_indexes(handle, inode, path);
2807 if (err)
2808 goto out;
2809 }
2810 }
2811 /* Mark modified extent as dirty */
2812 err = ext4_ext_dirty(handle, inode, path + depth);
2813 goto out;
2814insert:
Mingming Cao00314622009-09-28 15:49:08 -04002815 err = ext4_ext_insert_extent(handle, inode, path, &newex, 0);
Dmitry Monakhov21ca0872010-05-16 06:00:00 -04002816 if (err == -ENOSPC && may_zeroout) {
Aneesh Kumar K.V093a0882008-04-29 08:11:12 -04002817 err = ext4_ext_zeroout(inode, &orig_ex);
2818 if (err)
2819 goto fix_extent_len;
2820 /* update the extent length and mark as initialized */
Aneesh Kumar K.V95c38892008-04-17 10:38:59 -04002821 ex->ee_block = orig_ex.ee_block;
2822 ex->ee_len = orig_ex.ee_len;
Theodore Ts'obf89d162010-10-27 21:30:14 -04002823 ext4_ext_store_pblock(ex, ext4_ext_pblock(&orig_ex));
Aneesh Kumar K.V95c38892008-04-17 10:38:59 -04002824 ext4_ext_dirty(handle, inode, path + depth);
Aneesh Kumar K.V161e7b72008-04-29 22:03:59 -04002825 /* zero out the first half */
2826 return allocated;
Aneesh Kumar K.V093a0882008-04-29 08:11:12 -04002827 } else if (err)
2828 goto fix_extent_len;
Amit Arora56055d32007-07-17 21:42:38 -04002829out:
Mingming553f9002009-09-18 13:34:55 -04002830 ext4_ext_show_leaf(inode, path);
Amit Arora56055d32007-07-17 21:42:38 -04002831 return err ? err : allocated;
Aneesh Kumar K.V093a0882008-04-29 08:11:12 -04002832
2833fix_extent_len:
2834 ex->ee_block = orig_ex.ee_block;
2835 ex->ee_len = orig_ex.ee_len;
Theodore Ts'obf89d162010-10-27 21:30:14 -04002836 ext4_ext_store_pblock(ex, ext4_ext_pblock(&orig_ex));
Aneesh Kumar K.V093a0882008-04-29 08:11:12 -04002837 ext4_ext_mark_uninitialized(ex);
2838 ext4_ext_dirty(handle, inode, path + depth);
2839 return err;
Amit Arora56055d32007-07-17 21:42:38 -04002840}
2841
Aneesh Kumar K.Vc278bfe2008-01-28 23:58:27 -05002842/*
Theodore Ts'oe35fd662010-05-16 19:00:00 -04002843 * This function is called by ext4_ext_map_blocks() from
Mingming Cao00314622009-09-28 15:49:08 -04002844 * ext4_get_blocks_dio_write() when DIO to write
2845 * to an uninitialized extent.
2846 *
2847 * Writing to an uninitized extent may result in splitting the uninitialized
Uwe Kleine-Königb5950762010-11-01 15:38:34 -04002848 * extent into multiple /initialized uninitialized extents (up to three)
Mingming Cao00314622009-09-28 15:49:08 -04002849 * There are three possibilities:
2850 * a> There is no split required: Entire extent should be uninitialized
2851 * b> Splits in two extents: Write is happening at either end of the extent
2852 * c> Splits in three extents: Somone is writing in middle of the extent
2853 *
2854 * One of more index blocks maybe needed if the extent tree grow after
Uwe Kleine-Königb5950762010-11-01 15:38:34 -04002855 * the uninitialized extent split. To prevent ENOSPC occur at the IO
Mingming Cao00314622009-09-28 15:49:08 -04002856 * complete, we need to split the uninitialized extent before DIO submit
Uwe Kleine-König421f91d2010-06-11 12:17:00 +02002857 * the IO. The uninitialized extent called at this time will be split
Mingming Cao00314622009-09-28 15:49:08 -04002858 * into three uninitialized extent(at most). After IO complete, the part
2859 * being filled will be convert to initialized by the end_io callback function
2860 * via ext4_convert_unwritten_extents().
Mingmingba230c32009-11-06 04:01:23 -05002861 *
2862 * Returns the size of uninitialized extent to be written on success.
Mingming Cao00314622009-09-28 15:49:08 -04002863 */
2864static int ext4_split_unwritten_extents(handle_t *handle,
2865 struct inode *inode,
Theodore Ts'oe35fd662010-05-16 19:00:00 -04002866 struct ext4_map_blocks *map,
Mingming Cao00314622009-09-28 15:49:08 -04002867 struct ext4_ext_path *path,
Mingming Cao00314622009-09-28 15:49:08 -04002868 int flags)
2869{
2870 struct ext4_extent *ex, newex, orig_ex;
2871 struct ext4_extent *ex1 = NULL;
2872 struct ext4_extent *ex2 = NULL;
2873 struct ext4_extent *ex3 = NULL;
Dmitry Monakhov21ca0872010-05-16 06:00:00 -04002874 ext4_lblk_t ee_block, eof_block;
Mingming Cao00314622009-09-28 15:49:08 -04002875 unsigned int allocated, ee_len, depth;
2876 ext4_fsblk_t newblock;
2877 int err = 0;
Dmitry Monakhov21ca0872010-05-16 06:00:00 -04002878 int may_zeroout;
Mingming Cao00314622009-09-28 15:49:08 -04002879
Dmitry Monakhov21ca0872010-05-16 06:00:00 -04002880 ext_debug("ext4_split_unwritten_extents: inode %lu, logical"
2881 "block %llu, max_blocks %u\n", inode->i_ino,
Theodore Ts'oe35fd662010-05-16 19:00:00 -04002882 (unsigned long long)map->m_lblk, map->m_len);
Dmitry Monakhov21ca0872010-05-16 06:00:00 -04002883
2884 eof_block = (inode->i_size + inode->i_sb->s_blocksize - 1) >>
2885 inode->i_sb->s_blocksize_bits;
Theodore Ts'oe35fd662010-05-16 19:00:00 -04002886 if (eof_block < map->m_lblk + map->m_len)
2887 eof_block = map->m_lblk + map->m_len;
Dmitry Monakhov21ca0872010-05-16 06:00:00 -04002888
Mingming Cao00314622009-09-28 15:49:08 -04002889 depth = ext_depth(inode);
Mingming Cao00314622009-09-28 15:49:08 -04002890 ex = path[depth].p_ext;
2891 ee_block = le32_to_cpu(ex->ee_block);
2892 ee_len = ext4_ext_get_actual_len(ex);
Theodore Ts'oe35fd662010-05-16 19:00:00 -04002893 allocated = ee_len - (map->m_lblk - ee_block);
Theodore Ts'obf89d162010-10-27 21:30:14 -04002894 newblock = map->m_lblk - ee_block + ext4_ext_pblock(ex);
Dmitry Monakhov21ca0872010-05-16 06:00:00 -04002895
Mingming Cao00314622009-09-28 15:49:08 -04002896 ex2 = ex;
2897 orig_ex.ee_block = ex->ee_block;
2898 orig_ex.ee_len = cpu_to_le16(ee_len);
Theodore Ts'obf89d162010-10-27 21:30:14 -04002899 ext4_ext_store_pblock(&orig_ex, ext4_ext_pblock(ex));
Mingming Cao00314622009-09-28 15:49:08 -04002900
2901 /*
Dmitry Monakhov21ca0872010-05-16 06:00:00 -04002902 * It is safe to convert extent to initialized via explicit
2903 * zeroout only if extent is fully insde i_size or new_size.
2904 */
2905 may_zeroout = ee_block + ee_len <= eof_block;
2906
2907 /*
Mingmingba230c32009-11-06 04:01:23 -05002908 * If the uninitialized extent begins at the same logical
2909 * block where the write begins, and the write completely
2910 * covers the extent, then we don't need to split it.
Mingming Cao00314622009-09-28 15:49:08 -04002911 */
Theodore Ts'oe35fd662010-05-16 19:00:00 -04002912 if ((map->m_lblk == ee_block) && (allocated <= map->m_len))
Mingmingba230c32009-11-06 04:01:23 -05002913 return allocated;
Mingming Cao00314622009-09-28 15:49:08 -04002914
2915 err = ext4_ext_get_access(handle, inode, path + depth);
2916 if (err)
2917 goto out;
Theodore Ts'oe35fd662010-05-16 19:00:00 -04002918 /* ex1: ee_block to map->m_lblk - 1 : uninitialized */
2919 if (map->m_lblk > ee_block) {
Mingming Cao00314622009-09-28 15:49:08 -04002920 ex1 = ex;
Theodore Ts'oe35fd662010-05-16 19:00:00 -04002921 ex1->ee_len = cpu_to_le16(map->m_lblk - ee_block);
Mingming Cao00314622009-09-28 15:49:08 -04002922 ext4_ext_mark_uninitialized(ex1);
2923 ex2 = &newex;
2924 }
2925 /*
2926 * for sanity, update the length of the ex2 extent before
2927 * we insert ex3, if ex1 is NULL. This is to avoid temporary
2928 * overlap of blocks.
2929 */
Theodore Ts'oe35fd662010-05-16 19:00:00 -04002930 if (!ex1 && allocated > map->m_len)
2931 ex2->ee_len = cpu_to_le16(map->m_len);
Mingming Cao00314622009-09-28 15:49:08 -04002932 /* ex3: to ee_block + ee_len : uninitialised */
Theodore Ts'oe35fd662010-05-16 19:00:00 -04002933 if (allocated > map->m_len) {
Mingming Cao00314622009-09-28 15:49:08 -04002934 unsigned int newdepth;
2935 ex3 = &newex;
Theodore Ts'oe35fd662010-05-16 19:00:00 -04002936 ex3->ee_block = cpu_to_le32(map->m_lblk + map->m_len);
2937 ext4_ext_store_pblock(ex3, newblock + map->m_len);
2938 ex3->ee_len = cpu_to_le16(allocated - map->m_len);
Mingming Cao00314622009-09-28 15:49:08 -04002939 ext4_ext_mark_uninitialized(ex3);
2940 err = ext4_ext_insert_extent(handle, inode, path, ex3, flags);
Dmitry Monakhov21ca0872010-05-16 06:00:00 -04002941 if (err == -ENOSPC && may_zeroout) {
Mingming Cao00314622009-09-28 15:49:08 -04002942 err = ext4_ext_zeroout(inode, &orig_ex);
2943 if (err)
2944 goto fix_extent_len;
2945 /* update the extent length and mark as initialized */
2946 ex->ee_block = orig_ex.ee_block;
2947 ex->ee_len = orig_ex.ee_len;
Theodore Ts'obf89d162010-10-27 21:30:14 -04002948 ext4_ext_store_pblock(ex, ext4_ext_pblock(&orig_ex));
Mingming Cao00314622009-09-28 15:49:08 -04002949 ext4_ext_dirty(handle, inode, path + depth);
2950 /* zeroed the full extent */
Theodore Ts'oe35fd662010-05-16 19:00:00 -04002951 /* blocks available from map->m_lblk */
Mingming Cao00314622009-09-28 15:49:08 -04002952 return allocated;
2953
2954 } else if (err)
2955 goto fix_extent_len;
2956 /*
2957 * The depth, and hence eh & ex might change
2958 * as part of the insert above.
2959 */
2960 newdepth = ext_depth(inode);
2961 /*
2962 * update the extent length after successful insert of the
2963 * split extent
2964 */
Dmitry Monakhov21ca0872010-05-16 06:00:00 -04002965 ee_len -= ext4_ext_get_actual_len(ex3);
2966 orig_ex.ee_len = cpu_to_le16(ee_len);
2967 may_zeroout = ee_block + ee_len <= eof_block;
2968
Mingming Cao00314622009-09-28 15:49:08 -04002969 depth = newdepth;
2970 ext4_ext_drop_refs(path);
Theodore Ts'oe35fd662010-05-16 19:00:00 -04002971 path = ext4_ext_find_extent(inode, map->m_lblk, path);
Mingming Cao00314622009-09-28 15:49:08 -04002972 if (IS_ERR(path)) {
2973 err = PTR_ERR(path);
2974 goto out;
2975 }
Mingming Cao00314622009-09-28 15:49:08 -04002976 ex = path[depth].p_ext;
2977 if (ex2 != &newex)
2978 ex2 = ex;
2979
2980 err = ext4_ext_get_access(handle, inode, path + depth);
2981 if (err)
2982 goto out;
2983
Theodore Ts'oe35fd662010-05-16 19:00:00 -04002984 allocated = map->m_len;
Mingming Cao00314622009-09-28 15:49:08 -04002985 }
2986 /*
2987 * If there was a change of depth as part of the
2988 * insertion of ex3 above, we need to update the length
2989 * of the ex1 extent again here
2990 */
2991 if (ex1 && ex1 != ex) {
2992 ex1 = ex;
Theodore Ts'oe35fd662010-05-16 19:00:00 -04002993 ex1->ee_len = cpu_to_le16(map->m_lblk - ee_block);
Mingming Cao00314622009-09-28 15:49:08 -04002994 ext4_ext_mark_uninitialized(ex1);
2995 ex2 = &newex;
2996 }
2997 /*
Theodore Ts'oe35fd662010-05-16 19:00:00 -04002998 * ex2: map->m_lblk to map->m_lblk + map->m_len-1 : to be written
2999 * using direct I/O, uninitialised still.
Mingming Cao00314622009-09-28 15:49:08 -04003000 */
Theodore Ts'oe35fd662010-05-16 19:00:00 -04003001 ex2->ee_block = cpu_to_le32(map->m_lblk);
Mingming Cao00314622009-09-28 15:49:08 -04003002 ext4_ext_store_pblock(ex2, newblock);
3003 ex2->ee_len = cpu_to_le16(allocated);
3004 ext4_ext_mark_uninitialized(ex2);
3005 if (ex2 != ex)
3006 goto insert;
3007 /* Mark modified extent as dirty */
3008 err = ext4_ext_dirty(handle, inode, path + depth);
3009 ext_debug("out here\n");
3010 goto out;
3011insert:
3012 err = ext4_ext_insert_extent(handle, inode, path, &newex, flags);
Dmitry Monakhov21ca0872010-05-16 06:00:00 -04003013 if (err == -ENOSPC && may_zeroout) {
Mingming Cao00314622009-09-28 15:49:08 -04003014 err = ext4_ext_zeroout(inode, &orig_ex);
3015 if (err)
3016 goto fix_extent_len;
3017 /* update the extent length and mark as initialized */
3018 ex->ee_block = orig_ex.ee_block;
3019 ex->ee_len = orig_ex.ee_len;
Theodore Ts'obf89d162010-10-27 21:30:14 -04003020 ext4_ext_store_pblock(ex, ext4_ext_pblock(&orig_ex));
Mingming Cao00314622009-09-28 15:49:08 -04003021 ext4_ext_dirty(handle, inode, path + depth);
3022 /* zero out the first half */
3023 return allocated;
3024 } else if (err)
3025 goto fix_extent_len;
3026out:
3027 ext4_ext_show_leaf(inode, path);
3028 return err ? err : allocated;
3029
3030fix_extent_len:
3031 ex->ee_block = orig_ex.ee_block;
3032 ex->ee_len = orig_ex.ee_len;
Theodore Ts'obf89d162010-10-27 21:30:14 -04003033 ext4_ext_store_pblock(ex, ext4_ext_pblock(&orig_ex));
Mingming Cao00314622009-09-28 15:49:08 -04003034 ext4_ext_mark_uninitialized(ex);
3035 ext4_ext_dirty(handle, inode, path + depth);
3036 return err;
3037}
Jiaying Zhangc7064ef2010-03-02 13:28:44 -05003038static int ext4_convert_unwritten_extents_endio(handle_t *handle,
Mingming Cao00314622009-09-28 15:49:08 -04003039 struct inode *inode,
3040 struct ext4_ext_path *path)
3041{
3042 struct ext4_extent *ex;
3043 struct ext4_extent_header *eh;
3044 int depth;
3045 int err = 0;
3046 int ret = 0;
3047
3048 depth = ext_depth(inode);
3049 eh = path[depth].p_hdr;
3050 ex = path[depth].p_ext;
3051
3052 err = ext4_ext_get_access(handle, inode, path + depth);
3053 if (err)
3054 goto out;
3055 /* first mark the extent as initialized */
3056 ext4_ext_mark_initialized(ex);
3057
3058 /*
3059 * We have to see if it can be merged with the extent
3060 * on the left.
3061 */
3062 if (ex > EXT_FIRST_EXTENT(eh)) {
3063 /*
3064 * To merge left, pass "ex - 1" to try_to_merge(),
3065 * since it merges towards right _only_.
3066 */
3067 ret = ext4_ext_try_to_merge(inode, path, ex - 1);
3068 if (ret) {
3069 err = ext4_ext_correct_indexes(handle, inode, path);
3070 if (err)
3071 goto out;
3072 depth = ext_depth(inode);
3073 ex--;
3074 }
3075 }
3076 /*
3077 * Try to Merge towards right.
3078 */
3079 ret = ext4_ext_try_to_merge(inode, path, ex);
3080 if (ret) {
3081 err = ext4_ext_correct_indexes(handle, inode, path);
3082 if (err)
3083 goto out;
3084 depth = ext_depth(inode);
3085 }
3086 /* Mark modified extent as dirty */
3087 err = ext4_ext_dirty(handle, inode, path + depth);
3088out:
3089 ext4_ext_show_leaf(inode, path);
3090 return err;
3091}
3092
Aneesh Kumar K.V515f41c2009-12-29 23:39:06 -05003093static void unmap_underlying_metadata_blocks(struct block_device *bdev,
3094 sector_t block, int count)
3095{
3096 int i;
3097 for (i = 0; i < count; i++)
3098 unmap_underlying_metadata(bdev, block + i);
3099}
3100
Theodore Ts'o58590b02010-10-27 21:23:12 -04003101/*
3102 * Handle EOFBLOCKS_FL flag, clearing it if necessary
3103 */
3104static int check_eofblocks_fl(handle_t *handle, struct inode *inode,
Eric Sandeend002ebf2011-01-10 13:03:35 -05003105 ext4_lblk_t lblk,
Theodore Ts'o58590b02010-10-27 21:23:12 -04003106 struct ext4_ext_path *path,
3107 unsigned int len)
3108{
3109 int i, depth;
3110 struct ext4_extent_header *eh;
3111 struct ext4_extent *ex, *last_ex;
3112
3113 if (!ext4_test_inode_flag(inode, EXT4_INODE_EOFBLOCKS))
3114 return 0;
3115
3116 depth = ext_depth(inode);
3117 eh = path[depth].p_hdr;
3118 ex = path[depth].p_ext;
3119
3120 if (unlikely(!eh->eh_entries)) {
3121 EXT4_ERROR_INODE(inode, "eh->eh_entries == 0 and "
3122 "EOFBLOCKS_FL set");
3123 return -EIO;
3124 }
3125 last_ex = EXT_LAST_EXTENT(eh);
3126 /*
3127 * We should clear the EOFBLOCKS_FL flag if we are writing the
3128 * last block in the last extent in the file. We test this by
3129 * first checking to see if the caller to
3130 * ext4_ext_get_blocks() was interested in the last block (or
3131 * a block beyond the last block) in the current extent. If
3132 * this turns out to be false, we can bail out from this
3133 * function immediately.
3134 */
Eric Sandeend002ebf2011-01-10 13:03:35 -05003135 if (lblk + len < le32_to_cpu(last_ex->ee_block) +
Theodore Ts'o58590b02010-10-27 21:23:12 -04003136 ext4_ext_get_actual_len(last_ex))
3137 return 0;
3138 /*
3139 * If the caller does appear to be planning to write at or
3140 * beyond the end of the current extent, we then test to see
3141 * if the current extent is the last extent in the file, by
3142 * checking to make sure it was reached via the rightmost node
3143 * at each level of the tree.
3144 */
3145 for (i = depth-1; i >= 0; i--)
3146 if (path[i].p_idx != EXT_LAST_INDEX(path[i].p_hdr))
3147 return 0;
3148 ext4_clear_inode_flag(inode, EXT4_INODE_EOFBLOCKS);
3149 return ext4_mark_inode_dirty(handle, inode);
3150}
3151
Mingming Cao00314622009-09-28 15:49:08 -04003152static int
3153ext4_ext_handle_uninitialized_extents(handle_t *handle, struct inode *inode,
Theodore Ts'oe35fd662010-05-16 19:00:00 -04003154 struct ext4_map_blocks *map,
Mingming Cao00314622009-09-28 15:49:08 -04003155 struct ext4_ext_path *path, int flags,
Theodore Ts'oe35fd662010-05-16 19:00:00 -04003156 unsigned int allocated, ext4_fsblk_t newblock)
Mingming Cao00314622009-09-28 15:49:08 -04003157{
3158 int ret = 0;
3159 int err = 0;
Mingming Cao8d5d02e2009-09-28 15:48:29 -04003160 ext4_io_end_t *io = EXT4_I(inode)->cur_aio_dio;
Mingming Cao00314622009-09-28 15:49:08 -04003161
3162 ext_debug("ext4_ext_handle_uninitialized_extents: inode %lu, logical"
3163 "block %llu, max_blocks %u, flags %d, allocated %u",
Theodore Ts'oe35fd662010-05-16 19:00:00 -04003164 inode->i_ino, (unsigned long long)map->m_lblk, map->m_len,
Mingming Cao00314622009-09-28 15:49:08 -04003165 flags, allocated);
3166 ext4_ext_show_leaf(inode, path);
3167
Jiaying Zhangc7064ef2010-03-02 13:28:44 -05003168 /* get_block() before submit the IO, split the extent */
Jiaying Zhang744692d2010-03-04 16:14:02 -05003169 if ((flags & EXT4_GET_BLOCKS_PRE_IO)) {
Theodore Ts'oe35fd662010-05-16 19:00:00 -04003170 ret = ext4_split_unwritten_extents(handle, inode, map,
3171 path, flags);
Mingming5f524952009-11-10 10:48:04 -05003172 /*
3173 * Flag the inode(non aio case) or end_io struct (aio case)
3174 * that this IO needs to convertion to written when IO is
3175 * completed
3176 */
Eric Sandeene9e3bce2011-02-12 08:17:34 -05003177 if (io && !(io->flag & EXT4_IO_END_UNWRITTEN)) {
Theodore Ts'obd2d0212010-10-27 21:30:10 -04003178 io->flag = EXT4_IO_END_UNWRITTEN;
Eric Sandeene9e3bce2011-02-12 08:17:34 -05003179 atomic_inc(&EXT4_I(inode)->i_aiodio_unwritten);
3180 } else
Theodore Ts'o19f5fb72010-01-24 14:34:07 -05003181 ext4_set_inode_state(inode, EXT4_STATE_DIO_UNWRITTEN);
Jiaying Zhang744692d2010-03-04 16:14:02 -05003182 if (ext4_should_dioread_nolock(inode))
Theodore Ts'oe35fd662010-05-16 19:00:00 -04003183 map->m_flags |= EXT4_MAP_UNINIT;
Mingming Cao00314622009-09-28 15:49:08 -04003184 goto out;
3185 }
Jiaying Zhangc7064ef2010-03-02 13:28:44 -05003186 /* IO end_io complete, convert the filled extent to written */
Jiaying Zhang744692d2010-03-04 16:14:02 -05003187 if ((flags & EXT4_GET_BLOCKS_CONVERT)) {
Jiaying Zhangc7064ef2010-03-02 13:28:44 -05003188 ret = ext4_convert_unwritten_extents_endio(handle, inode,
Mingming Cao00314622009-09-28 15:49:08 -04003189 path);
Theodore Ts'o58590b02010-10-27 21:23:12 -04003190 if (ret >= 0) {
Jan Karab436b9b2009-12-08 23:51:10 -05003191 ext4_update_inode_fsync_trans(handle, inode, 1);
Eric Sandeend002ebf2011-01-10 13:03:35 -05003192 err = check_eofblocks_fl(handle, inode, map->m_lblk,
3193 path, map->m_len);
Theodore Ts'o58590b02010-10-27 21:23:12 -04003194 } else
3195 err = ret;
Mingming Cao00314622009-09-28 15:49:08 -04003196 goto out2;
3197 }
3198 /* buffered IO case */
3199 /*
3200 * repeat fallocate creation request
3201 * we already have an unwritten extent
3202 */
3203 if (flags & EXT4_GET_BLOCKS_UNINIT_EXT)
3204 goto map_out;
3205
3206 /* buffered READ or buffered write_begin() lookup */
3207 if ((flags & EXT4_GET_BLOCKS_CREATE) == 0) {
3208 /*
3209 * We have blocks reserved already. We
3210 * return allocated blocks so that delalloc
3211 * won't do block reservation for us. But
3212 * the buffer head will be unmapped so that
3213 * a read from the block returns 0s.
3214 */
Theodore Ts'oe35fd662010-05-16 19:00:00 -04003215 map->m_flags |= EXT4_MAP_UNWRITTEN;
Mingming Cao00314622009-09-28 15:49:08 -04003216 goto out1;
3217 }
3218
3219 /* buffered write, writepage time, convert*/
Theodore Ts'oe35fd662010-05-16 19:00:00 -04003220 ret = ext4_ext_convert_to_initialized(handle, inode, map, path);
Theodore Ts'o58590b02010-10-27 21:23:12 -04003221 if (ret >= 0) {
Jan Karab436b9b2009-12-08 23:51:10 -05003222 ext4_update_inode_fsync_trans(handle, inode, 1);
Eric Sandeend002ebf2011-01-10 13:03:35 -05003223 err = check_eofblocks_fl(handle, inode, map->m_lblk, path,
3224 map->m_len);
Theodore Ts'o58590b02010-10-27 21:23:12 -04003225 if (err < 0)
3226 goto out2;
3227 }
3228
Mingming Cao00314622009-09-28 15:49:08 -04003229out:
3230 if (ret <= 0) {
3231 err = ret;
3232 goto out2;
3233 } else
3234 allocated = ret;
Theodore Ts'oe35fd662010-05-16 19:00:00 -04003235 map->m_flags |= EXT4_MAP_NEW;
Aneesh Kumar K.V515f41c2009-12-29 23:39:06 -05003236 /*
3237 * if we allocated more blocks than requested
3238 * we need to make sure we unmap the extra block
3239 * allocated. The actual needed block will get
3240 * unmapped later when we find the buffer_head marked
3241 * new.
3242 */
Theodore Ts'oe35fd662010-05-16 19:00:00 -04003243 if (allocated > map->m_len) {
Aneesh Kumar K.V515f41c2009-12-29 23:39:06 -05003244 unmap_underlying_metadata_blocks(inode->i_sb->s_bdev,
Theodore Ts'oe35fd662010-05-16 19:00:00 -04003245 newblock + map->m_len,
3246 allocated - map->m_len);
3247 allocated = map->m_len;
Aneesh Kumar K.V515f41c2009-12-29 23:39:06 -05003248 }
Aneesh Kumar K.V5f634d02010-01-25 04:00:31 -05003249
3250 /*
3251 * If we have done fallocate with the offset that is already
3252 * delayed allocated, we would have block reservation
3253 * and quota reservation done in the delayed write path.
3254 * But fallocate would have already updated quota and block
3255 * count for this offset. So cancel these reservation
3256 */
Aneesh Kumar K.V1296cc82010-01-15 01:27:59 -05003257 if (flags & EXT4_GET_BLOCKS_DELALLOC_RESERVE)
Aneesh Kumar K.V5f634d02010-01-25 04:00:31 -05003258 ext4_da_update_reserve_space(inode, allocated, 0);
3259
Mingming Cao00314622009-09-28 15:49:08 -04003260map_out:
Theodore Ts'oe35fd662010-05-16 19:00:00 -04003261 map->m_flags |= EXT4_MAP_MAPPED;
Mingming Cao00314622009-09-28 15:49:08 -04003262out1:
Theodore Ts'oe35fd662010-05-16 19:00:00 -04003263 if (allocated > map->m_len)
3264 allocated = map->m_len;
Mingming Cao00314622009-09-28 15:49:08 -04003265 ext4_ext_show_leaf(inode, path);
Theodore Ts'oe35fd662010-05-16 19:00:00 -04003266 map->m_pblk = newblock;
3267 map->m_len = allocated;
Mingming Cao00314622009-09-28 15:49:08 -04003268out2:
3269 if (path) {
3270 ext4_ext_drop_refs(path);
3271 kfree(path);
3272 }
3273 return err ? err : allocated;
3274}
Theodore Ts'o58590b02010-10-27 21:23:12 -04003275
Mingming Cao00314622009-09-28 15:49:08 -04003276/*
Mingming Caof5ab0d12008-02-25 15:29:55 -05003277 * Block allocation/map/preallocation routine for extents based files
3278 *
3279 *
Aneesh Kumar K.Vc278bfe2008-01-28 23:58:27 -05003280 * Need to be called with
Aneesh Kumar K.V0e855ac2008-01-28 23:58:26 -05003281 * down_read(&EXT4_I(inode)->i_data_sem) if not allocating file system block
3282 * (ie, create is zero). Otherwise down_write(&EXT4_I(inode)->i_data_sem)
Mingming Caof5ab0d12008-02-25 15:29:55 -05003283 *
3284 * return > 0, number of of blocks already mapped/allocated
3285 * if create == 0 and these are pre-allocated blocks
3286 * buffer head is unmapped
3287 * otherwise blocks are mapped
3288 *
3289 * return = 0, if plain look up failed (blocks have not been allocated)
3290 * buffer head is unmapped
3291 *
3292 * return < 0, error case.
Aneesh Kumar K.Vc278bfe2008-01-28 23:58:27 -05003293 */
Theodore Ts'oe35fd662010-05-16 19:00:00 -04003294int ext4_ext_map_blocks(handle_t *handle, struct inode *inode,
3295 struct ext4_map_blocks *map, int flags)
Alex Tomasa86c6182006-10-11 01:21:03 -07003296{
3297 struct ext4_ext_path *path = NULL;
Amit Arora56055d32007-07-17 21:42:38 -04003298 struct ext4_extent_header *eh;
Theodore Ts'o58590b02010-10-27 21:23:12 -04003299 struct ext4_extent newex, *ex;
Theodore Ts'o498e5f22008-11-05 00:14:04 -05003300 ext4_fsblk_t newblock;
Theodore Ts'ob05e6ae2011-01-10 12:13:26 -05003301 int err = 0, depth, ret;
Theodore Ts'o498e5f22008-11-05 00:14:04 -05003302 unsigned int allocated = 0;
Alex Tomasc9de5602008-01-29 00:19:52 -05003303 struct ext4_allocation_request ar;
Mingming Cao8d5d02e2009-09-28 15:48:29 -04003304 ext4_io_end_t *io = EXT4_I(inode)->cur_aio_dio;
Alex Tomasa86c6182006-10-11 01:21:03 -07003305
Mingming84fe3be2009-09-01 08:44:37 -04003306 ext_debug("blocks %u/%u requested for inode %lu\n",
Theodore Ts'oe35fd662010-05-16 19:00:00 -04003307 map->m_lblk, map->m_len, inode->i_ino);
Alex Tomasa86c6182006-10-11 01:21:03 -07003308
3309 /* check in cache */
Theodore Ts'ob05e6ae2011-01-10 12:13:26 -05003310 if (ext4_ext_in_cache(inode, map->m_lblk, &newex)) {
3311 if (!newex.ee_start_lo && !newex.ee_start_hi) {
Theodore Ts'oc2177052009-05-14 00:58:52 -04003312 if ((flags & EXT4_GET_BLOCKS_CREATE) == 0) {
Amit Arora56055d32007-07-17 21:42:38 -04003313 /*
3314 * block isn't allocated yet and
3315 * user doesn't want to allocate it
3316 */
Alex Tomasa86c6182006-10-11 01:21:03 -07003317 goto out2;
3318 }
3319 /* we should allocate requested block */
Theodore Ts'ob05e6ae2011-01-10 12:13:26 -05003320 } else {
Alex Tomasa86c6182006-10-11 01:21:03 -07003321 /* block is already allocated */
Theodore Ts'oe35fd662010-05-16 19:00:00 -04003322 newblock = map->m_lblk
Dave Kleikamp8c55e202007-05-24 13:04:54 -04003323 - le32_to_cpu(newex.ee_block)
Theodore Ts'obf89d162010-10-27 21:30:14 -04003324 + ext4_ext_pblock(&newex);
Randy Dunlapd0d856e2006-10-11 01:21:07 -07003325 /* number of remaining blocks in the extent */
Aneesh Kumar K.Vb939e372008-01-28 23:58:27 -05003326 allocated = ext4_ext_get_actual_len(&newex) -
Theodore Ts'oe35fd662010-05-16 19:00:00 -04003327 (map->m_lblk - le32_to_cpu(newex.ee_block));
Alex Tomasa86c6182006-10-11 01:21:03 -07003328 goto out;
Alex Tomasa86c6182006-10-11 01:21:03 -07003329 }
3330 }
3331
3332 /* find extent for this block */
Theodore Ts'oe35fd662010-05-16 19:00:00 -04003333 path = ext4_ext_find_extent(inode, map->m_lblk, NULL);
Alex Tomasa86c6182006-10-11 01:21:03 -07003334 if (IS_ERR(path)) {
3335 err = PTR_ERR(path);
3336 path = NULL;
3337 goto out2;
3338 }
3339
3340 depth = ext_depth(inode);
3341
3342 /*
Randy Dunlapd0d856e2006-10-11 01:21:07 -07003343 * consistent leaf must not be empty;
3344 * this situation is possible, though, _during_ tree modification;
Alex Tomasa86c6182006-10-11 01:21:03 -07003345 * this is why assert can't be put in ext4_ext_find_extent()
3346 */
Frank Mayhar273df552010-03-02 11:46:09 -05003347 if (unlikely(path[depth].p_ext == NULL && depth != 0)) {
3348 EXT4_ERROR_INODE(inode, "bad extent address "
Theodore Ts'of70f3622010-05-16 23:00:00 -04003349 "lblock: %lu, depth: %d pblock %lld",
3350 (unsigned long) map->m_lblk, depth,
3351 path[depth].p_block);
Surbhi Palande034fb4c2009-12-14 09:53:52 -05003352 err = -EIO;
3353 goto out2;
3354 }
Amit Arora56055d32007-07-17 21:42:38 -04003355 eh = path[depth].p_hdr;
Alex Tomasa86c6182006-10-11 01:21:03 -07003356
Avantika Mathur7e028972006-12-06 20:41:33 -08003357 ex = path[depth].p_ext;
3358 if (ex) {
Aneesh Kumar K.V725d26d2008-01-28 23:58:27 -05003359 ext4_lblk_t ee_block = le32_to_cpu(ex->ee_block);
Theodore Ts'obf89d162010-10-27 21:30:14 -04003360 ext4_fsblk_t ee_start = ext4_ext_pblock(ex);
Amit Aroraa2df2a62007-07-17 21:42:41 -04003361 unsigned short ee_len;
Suparna Bhattacharya471d4012006-10-11 01:21:06 -07003362
3363 /*
Suparna Bhattacharya471d4012006-10-11 01:21:06 -07003364 * Uninitialized extents are treated as holes, except that
Amit Arora56055d32007-07-17 21:42:38 -04003365 * we split out initialized portions during a write.
Suparna Bhattacharya471d4012006-10-11 01:21:06 -07003366 */
Amit Aroraa2df2a62007-07-17 21:42:41 -04003367 ee_len = ext4_ext_get_actual_len(ex);
Randy Dunlapd0d856e2006-10-11 01:21:07 -07003368 /* if found extent covers block, simply return it */
Theodore Ts'oe35fd662010-05-16 19:00:00 -04003369 if (in_range(map->m_lblk, ee_block, ee_len)) {
3370 newblock = map->m_lblk - ee_block + ee_start;
Randy Dunlapd0d856e2006-10-11 01:21:07 -07003371 /* number of remaining blocks in the extent */
Theodore Ts'oe35fd662010-05-16 19:00:00 -04003372 allocated = ee_len - (map->m_lblk - ee_block);
3373 ext_debug("%u fit into %u:%d -> %llu\n", map->m_lblk,
3374 ee_block, ee_len, newblock);
Amit Arora56055d32007-07-17 21:42:38 -04003375
Amit Aroraa2df2a62007-07-17 21:42:41 -04003376 /* Do not put uninitialized extent in the cache */
Amit Arora56055d32007-07-17 21:42:38 -04003377 if (!ext4_ext_is_uninitialized(ex)) {
Amit Aroraa2df2a62007-07-17 21:42:41 -04003378 ext4_ext_put_in_cache(inode, ee_block,
Theodore Ts'ob05e6ae2011-01-10 12:13:26 -05003379 ee_len, ee_start);
Amit Arora56055d32007-07-17 21:42:38 -04003380 goto out;
3381 }
Mingming Cao00314622009-09-28 15:49:08 -04003382 ret = ext4_ext_handle_uninitialized_extents(handle,
Theodore Ts'oe35fd662010-05-16 19:00:00 -04003383 inode, map, path, flags, allocated,
3384 newblock);
Mingming Cao00314622009-09-28 15:49:08 -04003385 return ret;
Alex Tomasa86c6182006-10-11 01:21:03 -07003386 }
3387 }
3388
3389 /*
Randy Dunlapd0d856e2006-10-11 01:21:07 -07003390 * requested block isn't allocated yet;
Alex Tomasa86c6182006-10-11 01:21:03 -07003391 * we couldn't try to create block if create flag is zero
3392 */
Theodore Ts'oc2177052009-05-14 00:58:52 -04003393 if ((flags & EXT4_GET_BLOCKS_CREATE) == 0) {
Amit Arora56055d32007-07-17 21:42:38 -04003394 /*
3395 * put just found gap into cache to speed up
3396 * subsequent requests
3397 */
Theodore Ts'oe35fd662010-05-16 19:00:00 -04003398 ext4_ext_put_gap_in_cache(inode, path, map->m_lblk);
Alex Tomasa86c6182006-10-11 01:21:03 -07003399 goto out2;
3400 }
3401 /*
Theodore Ts'oc2ea3fd2008-10-10 09:40:52 -04003402 * Okay, we need to do block allocation.
Andrew Morton63f57932006-10-11 01:21:24 -07003403 */
Alex Tomasa86c6182006-10-11 01:21:03 -07003404
Alex Tomasc9de5602008-01-29 00:19:52 -05003405 /* find neighbour allocated blocks */
Theodore Ts'oe35fd662010-05-16 19:00:00 -04003406 ar.lleft = map->m_lblk;
Alex Tomasc9de5602008-01-29 00:19:52 -05003407 err = ext4_ext_search_left(inode, path, &ar.lleft, &ar.pleft);
3408 if (err)
3409 goto out2;
Theodore Ts'oe35fd662010-05-16 19:00:00 -04003410 ar.lright = map->m_lblk;
Alex Tomasc9de5602008-01-29 00:19:52 -05003411 err = ext4_ext_search_right(inode, path, &ar.lright, &ar.pright);
3412 if (err)
3413 goto out2;
Amit Arora25d14f92007-05-24 13:04:13 -04003414
Amit Arora749269f2007-07-18 09:02:56 -04003415 /*
3416 * See if request is beyond maximum number of blocks we can have in
3417 * a single extent. For an initialized extent this limit is
3418 * EXT_INIT_MAX_LEN and for an uninitialized extent this limit is
3419 * EXT_UNINIT_MAX_LEN.
3420 */
Theodore Ts'oe35fd662010-05-16 19:00:00 -04003421 if (map->m_len > EXT_INIT_MAX_LEN &&
Theodore Ts'oc2177052009-05-14 00:58:52 -04003422 !(flags & EXT4_GET_BLOCKS_UNINIT_EXT))
Theodore Ts'oe35fd662010-05-16 19:00:00 -04003423 map->m_len = EXT_INIT_MAX_LEN;
3424 else if (map->m_len > EXT_UNINIT_MAX_LEN &&
Theodore Ts'oc2177052009-05-14 00:58:52 -04003425 (flags & EXT4_GET_BLOCKS_UNINIT_EXT))
Theodore Ts'oe35fd662010-05-16 19:00:00 -04003426 map->m_len = EXT_UNINIT_MAX_LEN;
Amit Arora749269f2007-07-18 09:02:56 -04003427
Theodore Ts'oe35fd662010-05-16 19:00:00 -04003428 /* Check if we can really insert (m_lblk)::(m_lblk + m_len) extent */
3429 newex.ee_block = cpu_to_le32(map->m_lblk);
3430 newex.ee_len = cpu_to_le16(map->m_len);
Amit Arora25d14f92007-05-24 13:04:13 -04003431 err = ext4_ext_check_overlap(inode, &newex, path);
3432 if (err)
Aneesh Kumar K.Vb939e372008-01-28 23:58:27 -05003433 allocated = ext4_ext_get_actual_len(&newex);
Amit Arora25d14f92007-05-24 13:04:13 -04003434 else
Theodore Ts'oe35fd662010-05-16 19:00:00 -04003435 allocated = map->m_len;
Alex Tomasc9de5602008-01-29 00:19:52 -05003436
3437 /* allocate new block */
3438 ar.inode = inode;
Theodore Ts'oe35fd662010-05-16 19:00:00 -04003439 ar.goal = ext4_ext_find_goal(inode, path, map->m_lblk);
3440 ar.logical = map->m_lblk;
Alex Tomasc9de5602008-01-29 00:19:52 -05003441 ar.len = allocated;
3442 if (S_ISREG(inode->i_mode))
3443 ar.flags = EXT4_MB_HINT_DATA;
3444 else
3445 /* disable in-core preallocation for non-regular files */
3446 ar.flags = 0;
3447 newblock = ext4_mb_new_blocks(handle, &ar, &err);
Alex Tomasa86c6182006-10-11 01:21:03 -07003448 if (!newblock)
3449 goto out2;
Mingming84fe3be2009-09-01 08:44:37 -04003450 ext_debug("allocate new block: goal %llu, found %llu/%u\n",
Theodore Ts'o498e5f22008-11-05 00:14:04 -05003451 ar.goal, newblock, allocated);
Alex Tomasa86c6182006-10-11 01:21:03 -07003452
3453 /* try to insert new extent into found leaf and return */
Alex Tomasf65e6fb2006-10-11 01:21:05 -07003454 ext4_ext_store_pblock(&newex, newblock);
Alex Tomasc9de5602008-01-29 00:19:52 -05003455 newex.ee_len = cpu_to_le16(ar.len);
Mingming Cao8d5d02e2009-09-28 15:48:29 -04003456 /* Mark uninitialized */
3457 if (flags & EXT4_GET_BLOCKS_UNINIT_EXT){
Amit Aroraa2df2a62007-07-17 21:42:41 -04003458 ext4_ext_mark_uninitialized(&newex);
Mingming Cao8d5d02e2009-09-28 15:48:29 -04003459 /*
Jiaying Zhang744692d2010-03-04 16:14:02 -05003460 * io_end structure was created for every IO write to an
3461 * uninitialized extent. To avoid unecessary conversion,
3462 * here we flag the IO that really needs the conversion.
Mingming5f524952009-11-10 10:48:04 -05003463 * For non asycn direct IO case, flag the inode state
3464 * that we need to perform convertion when IO is done.
Mingming Cao8d5d02e2009-09-28 15:48:29 -04003465 */
Jiaying Zhang744692d2010-03-04 16:14:02 -05003466 if ((flags & EXT4_GET_BLOCKS_PRE_IO)) {
Eric Sandeene9e3bce2011-02-12 08:17:34 -05003467 if (io && !(io->flag & EXT4_IO_END_UNWRITTEN)) {
Theodore Ts'obd2d0212010-10-27 21:30:10 -04003468 io->flag = EXT4_IO_END_UNWRITTEN;
Eric Sandeene9e3bce2011-02-12 08:17:34 -05003469 atomic_inc(&EXT4_I(inode)->i_aiodio_unwritten);
3470 } else
Theodore Ts'o19f5fb72010-01-24 14:34:07 -05003471 ext4_set_inode_state(inode,
3472 EXT4_STATE_DIO_UNWRITTEN);
Mingming5f524952009-11-10 10:48:04 -05003473 }
Jiaying Zhang744692d2010-03-04 16:14:02 -05003474 if (ext4_should_dioread_nolock(inode))
Theodore Ts'oe35fd662010-05-16 19:00:00 -04003475 map->m_flags |= EXT4_MAP_UNINIT;
Mingming Cao8d5d02e2009-09-28 15:48:29 -04003476 }
Jiaying Zhangc8d46e42010-02-24 09:52:53 -05003477
Eric Sandeend002ebf2011-01-10 13:03:35 -05003478 err = check_eofblocks_fl(handle, inode, map->m_lblk, path, ar.len);
Theodore Ts'o58590b02010-10-27 21:23:12 -04003479 if (err)
3480 goto out2;
3481
Mingming Cao00314622009-09-28 15:49:08 -04003482 err = ext4_ext_insert_extent(handle, inode, path, &newex, flags);
Alex Tomas315054f2007-05-24 13:04:25 -04003483 if (err) {
3484 /* free data blocks we just allocated */
Alex Tomasc9de5602008-01-29 00:19:52 -05003485 /* not a good idea to call discard here directly,
3486 * but otherwise we'd need to call it every free() */
Theodore Ts'oc2ea3fd2008-10-10 09:40:52 -04003487 ext4_discard_preallocations(inode);
Theodore Ts'obf89d162010-10-27 21:30:14 -04003488 ext4_free_blocks(handle, inode, 0, ext4_ext_pblock(&newex),
Theodore Ts'oe6362602009-11-23 07:17:05 -05003489 ext4_ext_get_actual_len(&newex), 0);
Alex Tomasa86c6182006-10-11 01:21:03 -07003490 goto out2;
Alex Tomas315054f2007-05-24 13:04:25 -04003491 }
Alex Tomasa86c6182006-10-11 01:21:03 -07003492
Alex Tomasa86c6182006-10-11 01:21:03 -07003493 /* previous routine could use block we allocated */
Theodore Ts'obf89d162010-10-27 21:30:14 -04003494 newblock = ext4_ext_pblock(&newex);
Aneesh Kumar K.Vb939e372008-01-28 23:58:27 -05003495 allocated = ext4_ext_get_actual_len(&newex);
Theodore Ts'oe35fd662010-05-16 19:00:00 -04003496 if (allocated > map->m_len)
3497 allocated = map->m_len;
3498 map->m_flags |= EXT4_MAP_NEW;
Alex Tomasa86c6182006-10-11 01:21:03 -07003499
Jan Karab436b9b2009-12-08 23:51:10 -05003500 /*
Aneesh Kumar K.V5f634d02010-01-25 04:00:31 -05003501 * Update reserved blocks/metadata blocks after successful
3502 * block allocation which had been deferred till now.
3503 */
Aneesh Kumar K.V1296cc82010-01-15 01:27:59 -05003504 if (flags & EXT4_GET_BLOCKS_DELALLOC_RESERVE)
Aneesh Kumar K.V5f634d02010-01-25 04:00:31 -05003505 ext4_da_update_reserve_space(inode, allocated, 1);
3506
3507 /*
Jan Karab436b9b2009-12-08 23:51:10 -05003508 * Cache the extent and update transaction to commit on fdatasync only
3509 * when it is _not_ an uninitialized extent.
3510 */
3511 if ((flags & EXT4_GET_BLOCKS_UNINIT_EXT) == 0) {
Theodore Ts'ob05e6ae2011-01-10 12:13:26 -05003512 ext4_ext_put_in_cache(inode, map->m_lblk, allocated, newblock);
Jan Karab436b9b2009-12-08 23:51:10 -05003513 ext4_update_inode_fsync_trans(handle, inode, 1);
3514 } else
3515 ext4_update_inode_fsync_trans(handle, inode, 0);
Alex Tomasa86c6182006-10-11 01:21:03 -07003516out:
Theodore Ts'oe35fd662010-05-16 19:00:00 -04003517 if (allocated > map->m_len)
3518 allocated = map->m_len;
Alex Tomasa86c6182006-10-11 01:21:03 -07003519 ext4_ext_show_leaf(inode, path);
Theodore Ts'oe35fd662010-05-16 19:00:00 -04003520 map->m_flags |= EXT4_MAP_MAPPED;
3521 map->m_pblk = newblock;
3522 map->m_len = allocated;
Alex Tomasa86c6182006-10-11 01:21:03 -07003523out2:
3524 if (path) {
3525 ext4_ext_drop_refs(path);
3526 kfree(path);
3527 }
Alex Tomasa86c6182006-10-11 01:21:03 -07003528 return err ? err : allocated;
3529}
3530
Jan Karacf108bc2008-07-11 19:27:31 -04003531void ext4_ext_truncate(struct inode *inode)
Alex Tomasa86c6182006-10-11 01:21:03 -07003532{
3533 struct address_space *mapping = inode->i_mapping;
3534 struct super_block *sb = inode->i_sb;
Aneesh Kumar K.V725d26d2008-01-28 23:58:27 -05003535 ext4_lblk_t last_block;
Alex Tomasa86c6182006-10-11 01:21:03 -07003536 handle_t *handle;
3537 int err = 0;
3538
3539 /*
Jiaying Zhang3889fd52011-01-10 12:47:05 -05003540 * finish any pending end_io work so we won't run the risk of
3541 * converting any truncated blocks to initialized later
3542 */
3543 ext4_flush_completed_IO(inode);
3544
3545 /*
Alex Tomasa86c6182006-10-11 01:21:03 -07003546 * probably first extent we're gonna free will be last in block
3547 */
Mingming Caof3bd1f32008-08-19 22:16:03 -04003548 err = ext4_writepage_trans_blocks(inode);
Alex Tomasa86c6182006-10-11 01:21:03 -07003549 handle = ext4_journal_start(inode, err);
Jan Karacf108bc2008-07-11 19:27:31 -04003550 if (IS_ERR(handle))
Alex Tomasa86c6182006-10-11 01:21:03 -07003551 return;
Alex Tomasa86c6182006-10-11 01:21:03 -07003552
Jan Karacf108bc2008-07-11 19:27:31 -04003553 if (inode->i_size & (sb->s_blocksize - 1))
3554 ext4_block_truncate_page(handle, mapping, inode->i_size);
Alex Tomasa86c6182006-10-11 01:21:03 -07003555
Jan Kara9ddfc3d2008-07-11 19:27:31 -04003556 if (ext4_orphan_add(handle, inode))
3557 goto out_stop;
3558
Aneesh Kumar K.V0e855ac2008-01-28 23:58:26 -05003559 down_write(&EXT4_I(inode)->i_data_sem);
Alex Tomasa86c6182006-10-11 01:21:03 -07003560 ext4_ext_invalidate_cache(inode);
3561
Theodore Ts'oc2ea3fd2008-10-10 09:40:52 -04003562 ext4_discard_preallocations(inode);
Alex Tomasc9de5602008-01-29 00:19:52 -05003563
Alex Tomasa86c6182006-10-11 01:21:03 -07003564 /*
Randy Dunlapd0d856e2006-10-11 01:21:07 -07003565 * TODO: optimization is possible here.
3566 * Probably we need not scan at all,
3567 * because page truncation is enough.
Alex Tomasa86c6182006-10-11 01:21:03 -07003568 */
Alex Tomasa86c6182006-10-11 01:21:03 -07003569
3570 /* we have to know where to truncate from in crash case */
3571 EXT4_I(inode)->i_disksize = inode->i_size;
3572 ext4_mark_inode_dirty(handle, inode);
3573
3574 last_block = (inode->i_size + sb->s_blocksize - 1)
3575 >> EXT4_BLOCK_SIZE_BITS(sb);
3576 err = ext4_ext_remove_space(inode, last_block);
3577
3578 /* In a multi-transaction truncate, we only make the final
Amit Arora56055d32007-07-17 21:42:38 -04003579 * transaction synchronous.
3580 */
Alex Tomasa86c6182006-10-11 01:21:03 -07003581 if (IS_SYNC(inode))
Frank Mayhar03901312009-01-07 00:06:22 -05003582 ext4_handle_sync(handle);
Alex Tomasa86c6182006-10-11 01:21:03 -07003583
3584out_stop:
Jan Kara9ddfc3d2008-07-11 19:27:31 -04003585 up_write(&EXT4_I(inode)->i_data_sem);
Alex Tomasa86c6182006-10-11 01:21:03 -07003586 /*
Randy Dunlapd0d856e2006-10-11 01:21:07 -07003587 * If this was a simple ftruncate() and the file will remain alive,
Alex Tomasa86c6182006-10-11 01:21:03 -07003588 * then we need to clear up the orphan record which we created above.
3589 * However, if this was a real unlink then we were called by
3590 * ext4_delete_inode(), and we allow that function to clean up the
3591 * orphan info for us.
3592 */
3593 if (inode->i_nlink)
3594 ext4_orphan_del(handle, inode);
3595
Solofo Ramangalahyef737722008-04-29 22:00:41 -04003596 inode->i_mtime = inode->i_ctime = ext4_current_time(inode);
3597 ext4_mark_inode_dirty(handle, inode);
Alex Tomasa86c6182006-10-11 01:21:03 -07003598 ext4_journal_stop(handle);
3599}
3600
Aneesh Kumar K.Vfd287842008-04-29 08:11:12 -04003601static void ext4_falloc_update_inode(struct inode *inode,
3602 int mode, loff_t new_size, int update_ctime)
3603{
3604 struct timespec now;
3605
3606 if (update_ctime) {
3607 now = current_fs_time(inode->i_sb);
3608 if (!timespec_equal(&inode->i_ctime, &now))
3609 inode->i_ctime = now;
3610 }
3611 /*
3612 * Update only when preallocation was requested beyond
3613 * the file size.
3614 */
Aneesh Kumar K.Vcf17fea2008-09-13 13:06:18 -04003615 if (!(mode & FALLOC_FL_KEEP_SIZE)) {
3616 if (new_size > i_size_read(inode))
3617 i_size_write(inode, new_size);
3618 if (new_size > EXT4_I(inode)->i_disksize)
3619 ext4_update_i_disksize(inode, new_size);
Jiaying Zhangc8d46e42010-02-24 09:52:53 -05003620 } else {
3621 /*
3622 * Mark that we allocate beyond EOF so the subsequent truncate
3623 * can proceed even if the new size is the same as i_size.
3624 */
3625 if (new_size > i_size_read(inode))
Dmitry Monakhov12e9b892010-05-16 22:00:00 -04003626 ext4_set_inode_flag(inode, EXT4_INODE_EOFBLOCKS);
Aneesh Kumar K.Vfd287842008-04-29 08:11:12 -04003627 }
3628
3629}
3630
Amit Aroraa2df2a62007-07-17 21:42:41 -04003631/*
Christoph Hellwig2fe17c12011-01-14 13:07:43 +01003632 * preallocate space for a file. This implements ext4's fallocate file
Amit Aroraa2df2a62007-07-17 21:42:41 -04003633 * operation, which gets called from sys_fallocate system call.
3634 * For block-mapped files, posix_fallocate should fall back to the method
3635 * of writing zeroes to the required new blocks (the same behavior which is
3636 * expected for file systems which do not support fallocate() system call).
3637 */
Christoph Hellwig2fe17c12011-01-14 13:07:43 +01003638long ext4_fallocate(struct file *file, int mode, loff_t offset, loff_t len)
Amit Aroraa2df2a62007-07-17 21:42:41 -04003639{
Christoph Hellwig2fe17c12011-01-14 13:07:43 +01003640 struct inode *inode = file->f_path.dentry->d_inode;
Amit Aroraa2df2a62007-07-17 21:42:41 -04003641 handle_t *handle;
Aneesh Kumar K.Vfd287842008-04-29 08:11:12 -04003642 loff_t new_size;
Theodore Ts'o498e5f22008-11-05 00:14:04 -05003643 unsigned int max_blocks;
Amit Aroraa2df2a62007-07-17 21:42:41 -04003644 int ret = 0;
3645 int ret2 = 0;
3646 int retries = 0;
Theodore Ts'o2ed88682010-05-16 20:00:00 -04003647 struct ext4_map_blocks map;
Amit Aroraa2df2a62007-07-17 21:42:41 -04003648 unsigned int credits, blkbits = inode->i_blkbits;
3649
Josef Bacikd6dc8462010-11-17 20:46:18 -05003650 /* We only support the FALLOC_FL_KEEP_SIZE mode */
Christoph Hellwig64c23e82011-01-14 13:07:30 +01003651 if (mode & ~FALLOC_FL_KEEP_SIZE)
Josef Bacikd6dc8462010-11-17 20:46:18 -05003652 return -EOPNOTSUPP;
3653
Amit Aroraa2df2a62007-07-17 21:42:41 -04003654 /*
3655 * currently supporting (pre)allocate mode for extent-based
3656 * files _only_
3657 */
Dmitry Monakhov12e9b892010-05-16 22:00:00 -04003658 if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)))
Amit Aroraa2df2a62007-07-17 21:42:41 -04003659 return -EOPNOTSUPP;
3660
Theodore Ts'o2ed88682010-05-16 20:00:00 -04003661 map.m_lblk = offset >> blkbits;
Aneesh Kumar K.Vfd287842008-04-29 08:11:12 -04003662 /*
3663 * We can't just convert len to max_blocks because
3664 * If blocksize = 4096 offset = 3072 and len = 2048
3665 */
Amit Aroraa2df2a62007-07-17 21:42:41 -04003666 max_blocks = (EXT4_BLOCK_ALIGN(len + offset, blkbits) >> blkbits)
Theodore Ts'o2ed88682010-05-16 20:00:00 -04003667 - map.m_lblk;
Amit Aroraa2df2a62007-07-17 21:42:41 -04003668 /*
Mingming Caof3bd1f32008-08-19 22:16:03 -04003669 * credits to insert 1 extent into extent tree
Amit Aroraa2df2a62007-07-17 21:42:41 -04003670 */
Mingming Caof3bd1f32008-08-19 22:16:03 -04003671 credits = ext4_chunk_trans_blocks(inode, max_blocks);
Aneesh Kumar K.V55bd7252008-02-15 12:47:21 -05003672 mutex_lock(&inode->i_mutex);
Nikanth Karthikesan6d19c422010-05-16 14:00:00 -04003673 ret = inode_newsize_ok(inode, (len + offset));
3674 if (ret) {
3675 mutex_unlock(&inode->i_mutex);
3676 return ret;
3677 }
Amit Aroraa2df2a62007-07-17 21:42:41 -04003678retry:
3679 while (ret >= 0 && ret < max_blocks) {
Theodore Ts'o2ed88682010-05-16 20:00:00 -04003680 map.m_lblk = map.m_lblk + ret;
3681 map.m_len = max_blocks = max_blocks - ret;
Amit Aroraa2df2a62007-07-17 21:42:41 -04003682 handle = ext4_journal_start(inode, credits);
3683 if (IS_ERR(handle)) {
3684 ret = PTR_ERR(handle);
3685 break;
3686 }
Theodore Ts'o2ed88682010-05-16 20:00:00 -04003687 ret = ext4_map_blocks(handle, inode, &map,
Theodore Ts'oc2177052009-05-14 00:58:52 -04003688 EXT4_GET_BLOCKS_CREATE_UNINIT_EXT);
Aneesh Kumar K.V221879c2008-01-28 23:58:27 -05003689 if (ret <= 0) {
Aneesh Kumar K.V2c986152008-02-25 15:41:35 -05003690#ifdef EXT4FS_DEBUG
3691 WARN_ON(ret <= 0);
Theodore Ts'oe35fd662010-05-16 19:00:00 -04003692 printk(KERN_ERR "%s: ext4_ext_map_blocks "
Aneesh Kumar K.V2c986152008-02-25 15:41:35 -05003693 "returned error inode#%lu, block=%u, "
Thadeu Lima de Souza Cascardo9fd97842009-01-26 19:26:26 -05003694 "max_blocks=%u", __func__,
Kazuya Mioa6371b62010-10-27 21:30:15 -04003695 inode->i_ino, map.m_lblk, max_blocks);
Aneesh Kumar K.V2c986152008-02-25 15:41:35 -05003696#endif
Amit Aroraa2df2a62007-07-17 21:42:41 -04003697 ext4_mark_inode_dirty(handle, inode);
3698 ret2 = ext4_journal_stop(handle);
3699 break;
3700 }
Theodore Ts'o2ed88682010-05-16 20:00:00 -04003701 if ((map.m_lblk + ret) >= (EXT4_BLOCK_ALIGN(offset + len,
Aneesh Kumar K.Vfd287842008-04-29 08:11:12 -04003702 blkbits) >> blkbits))
3703 new_size = offset + len;
3704 else
Theodore Ts'o2ed88682010-05-16 20:00:00 -04003705 new_size = (map.m_lblk + ret) << blkbits;
Amit Aroraa2df2a62007-07-17 21:42:41 -04003706
Aneesh Kumar K.Vfd287842008-04-29 08:11:12 -04003707 ext4_falloc_update_inode(inode, mode, new_size,
Theodore Ts'o2ed88682010-05-16 20:00:00 -04003708 (map.m_flags & EXT4_MAP_NEW));
Amit Aroraa2df2a62007-07-17 21:42:41 -04003709 ext4_mark_inode_dirty(handle, inode);
3710 ret2 = ext4_journal_stop(handle);
3711 if (ret2)
3712 break;
3713 }
Aneesh Kumar K.Vfd287842008-04-29 08:11:12 -04003714 if (ret == -ENOSPC &&
3715 ext4_should_retry_alloc(inode->i_sb, &retries)) {
3716 ret = 0;
Amit Aroraa2df2a62007-07-17 21:42:41 -04003717 goto retry;
Amit Aroraa2df2a62007-07-17 21:42:41 -04003718 }
Aneesh Kumar K.V55bd7252008-02-15 12:47:21 -05003719 mutex_unlock(&inode->i_mutex);
Amit Aroraa2df2a62007-07-17 21:42:41 -04003720 return ret > 0 ? ret2 : ret;
3721}
Eric Sandeen6873fa02008-10-07 00:46:36 -04003722
3723/*
Mingming Cao00314622009-09-28 15:49:08 -04003724 * This function convert a range of blocks to written extents
3725 * The caller of this function will pass the start offset and the size.
3726 * all unwritten extents within this range will be converted to
3727 * written extents.
3728 *
3729 * This function is called from the direct IO end io call back
3730 * function, to convert the fallocated extents after IO is completed.
Mingming109f5562009-11-10 10:48:08 -05003731 * Returns 0 on success.
Mingming Cao00314622009-09-28 15:49:08 -04003732 */
3733int ext4_convert_unwritten_extents(struct inode *inode, loff_t offset,
Eric Sandeena1de02d2010-02-04 23:58:38 -05003734 ssize_t len)
Mingming Cao00314622009-09-28 15:49:08 -04003735{
3736 handle_t *handle;
Mingming Cao00314622009-09-28 15:49:08 -04003737 unsigned int max_blocks;
3738 int ret = 0;
3739 int ret2 = 0;
Theodore Ts'o2ed88682010-05-16 20:00:00 -04003740 struct ext4_map_blocks map;
Mingming Cao00314622009-09-28 15:49:08 -04003741 unsigned int credits, blkbits = inode->i_blkbits;
3742
Theodore Ts'o2ed88682010-05-16 20:00:00 -04003743 map.m_lblk = offset >> blkbits;
Mingming Cao00314622009-09-28 15:49:08 -04003744 /*
3745 * We can't just convert len to max_blocks because
3746 * If blocksize = 4096 offset = 3072 and len = 2048
3747 */
Theodore Ts'o2ed88682010-05-16 20:00:00 -04003748 max_blocks = ((EXT4_BLOCK_ALIGN(len + offset, blkbits) >> blkbits) -
3749 map.m_lblk);
Mingming Cao00314622009-09-28 15:49:08 -04003750 /*
3751 * credits to insert 1 extent into extent tree
3752 */
3753 credits = ext4_chunk_trans_blocks(inode, max_blocks);
3754 while (ret >= 0 && ret < max_blocks) {
Theodore Ts'o2ed88682010-05-16 20:00:00 -04003755 map.m_lblk += ret;
3756 map.m_len = (max_blocks -= ret);
Mingming Cao00314622009-09-28 15:49:08 -04003757 handle = ext4_journal_start(inode, credits);
3758 if (IS_ERR(handle)) {
3759 ret = PTR_ERR(handle);
3760 break;
3761 }
Theodore Ts'o2ed88682010-05-16 20:00:00 -04003762 ret = ext4_map_blocks(handle, inode, &map,
Jiaying Zhangc7064ef2010-03-02 13:28:44 -05003763 EXT4_GET_BLOCKS_IO_CONVERT_EXT);
Mingming Cao00314622009-09-28 15:49:08 -04003764 if (ret <= 0) {
3765 WARN_ON(ret <= 0);
Theodore Ts'oe35fd662010-05-16 19:00:00 -04003766 printk(KERN_ERR "%s: ext4_ext_map_blocks "
Mingming Cao00314622009-09-28 15:49:08 -04003767 "returned error inode#%lu, block=%u, "
3768 "max_blocks=%u", __func__,
Theodore Ts'o2ed88682010-05-16 20:00:00 -04003769 inode->i_ino, map.m_lblk, map.m_len);
Mingming Cao00314622009-09-28 15:49:08 -04003770 }
3771 ext4_mark_inode_dirty(handle, inode);
3772 ret2 = ext4_journal_stop(handle);
3773 if (ret <= 0 || ret2 )
3774 break;
3775 }
3776 return ret > 0 ? ret2 : ret;
3777}
3778/*
Eric Sandeen6873fa02008-10-07 00:46:36 -04003779 * Callback function called for each extent to gather FIEMAP information.
3780 */
Aneesh Kumar K.V3a06d772008-11-22 15:04:59 -05003781static int ext4_ext_fiemap_cb(struct inode *inode, struct ext4_ext_path *path,
Eric Sandeen6873fa02008-10-07 00:46:36 -04003782 struct ext4_ext_cache *newex, struct ext4_extent *ex,
3783 void *data)
3784{
3785 struct fiemap_extent_info *fieinfo = data;
Eric Sandeenc9877b22009-05-01 23:32:06 -04003786 unsigned char blksize_bits = inode->i_sb->s_blocksize_bits;
Eric Sandeen6873fa02008-10-07 00:46:36 -04003787 __u64 logical;
3788 __u64 physical;
3789 __u64 length;
3790 __u32 flags = 0;
3791 int error;
3792
3793 logical = (__u64)newex->ec_block << blksize_bits;
3794
Theodore Ts'ob05e6ae2011-01-10 12:13:26 -05003795 if (newex->ec_start == 0) {
Eric Sandeen6873fa02008-10-07 00:46:36 -04003796 pgoff_t offset;
3797 struct page *page;
3798 struct buffer_head *bh = NULL;
3799
3800 offset = logical >> PAGE_SHIFT;
3801 page = find_get_page(inode->i_mapping, offset);
3802 if (!page || !page_has_buffers(page))
3803 return EXT_CONTINUE;
3804
3805 bh = page_buffers(page);
3806
3807 if (!bh)
3808 return EXT_CONTINUE;
3809
3810 if (buffer_delay(bh)) {
3811 flags |= FIEMAP_EXTENT_DELALLOC;
3812 page_cache_release(page);
3813 } else {
3814 page_cache_release(page);
3815 return EXT_CONTINUE;
3816 }
3817 }
3818
3819 physical = (__u64)newex->ec_start << blksize_bits;
3820 length = (__u64)newex->ec_len << blksize_bits;
3821
3822 if (ex && ext4_ext_is_uninitialized(ex))
3823 flags |= FIEMAP_EXTENT_UNWRITTEN;
3824
3825 /*
3826 * If this extent reaches EXT_MAX_BLOCK, it must be last.
3827 *
3828 * Or if ext4_ext_next_allocated_block is EXT_MAX_BLOCK,
3829 * this also indicates no more allocated blocks.
3830 *
3831 * XXX this might miss a single-block extent at EXT_MAX_BLOCK
3832 */
Eric Sandeenc9877b22009-05-01 23:32:06 -04003833 if (ext4_ext_next_allocated_block(path) == EXT_MAX_BLOCK ||
Theodore Ts'oeefd7f02009-05-02 19:05:37 -04003834 newex->ec_block + newex->ec_len - 1 == EXT_MAX_BLOCK) {
3835 loff_t size = i_size_read(inode);
3836 loff_t bs = EXT4_BLOCK_SIZE(inode->i_sb);
3837
Eric Sandeen6873fa02008-10-07 00:46:36 -04003838 flags |= FIEMAP_EXTENT_LAST;
Theodore Ts'oeefd7f02009-05-02 19:05:37 -04003839 if ((flags & FIEMAP_EXTENT_DELALLOC) &&
3840 logical+length > size)
3841 length = (size - logical + bs - 1) & ~(bs-1);
3842 }
Eric Sandeen6873fa02008-10-07 00:46:36 -04003843
3844 error = fiemap_fill_next_extent(fieinfo, logical, physical,
3845 length, flags);
3846 if (error < 0)
3847 return error;
3848 if (error == 1)
3849 return EXT_BREAK;
3850
3851 return EXT_CONTINUE;
3852}
3853
3854/* fiemap flags we can handle specified here */
3855#define EXT4_FIEMAP_FLAGS (FIEMAP_FLAG_SYNC|FIEMAP_FLAG_XATTR)
3856
Aneesh Kumar K.V3a06d772008-11-22 15:04:59 -05003857static int ext4_xattr_fiemap(struct inode *inode,
3858 struct fiemap_extent_info *fieinfo)
Eric Sandeen6873fa02008-10-07 00:46:36 -04003859{
3860 __u64 physical = 0;
3861 __u64 length;
3862 __u32 flags = FIEMAP_EXTENT_LAST;
3863 int blockbits = inode->i_sb->s_blocksize_bits;
3864 int error = 0;
3865
3866 /* in-inode? */
Theodore Ts'o19f5fb72010-01-24 14:34:07 -05003867 if (ext4_test_inode_state(inode, EXT4_STATE_XATTR)) {
Eric Sandeen6873fa02008-10-07 00:46:36 -04003868 struct ext4_iloc iloc;
3869 int offset; /* offset of xattr in inode */
3870
3871 error = ext4_get_inode_loc(inode, &iloc);
3872 if (error)
3873 return error;
3874 physical = iloc.bh->b_blocknr << blockbits;
3875 offset = EXT4_GOOD_OLD_INODE_SIZE +
3876 EXT4_I(inode)->i_extra_isize;
3877 physical += offset;
3878 length = EXT4_SB(inode->i_sb)->s_inode_size - offset;
3879 flags |= FIEMAP_EXTENT_DATA_INLINE;
Curt Wohlgemuthfd2dd9f2010-04-03 17:44:16 -04003880 brelse(iloc.bh);
Eric Sandeen6873fa02008-10-07 00:46:36 -04003881 } else { /* external block */
3882 physical = EXT4_I(inode)->i_file_acl << blockbits;
3883 length = inode->i_sb->s_blocksize;
3884 }
3885
3886 if (physical)
3887 error = fiemap_fill_next_extent(fieinfo, 0, physical,
3888 length, flags);
3889 return (error < 0 ? error : 0);
3890}
3891
3892int ext4_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
3893 __u64 start, __u64 len)
3894{
3895 ext4_lblk_t start_blk;
Eric Sandeen6873fa02008-10-07 00:46:36 -04003896 int error = 0;
3897
3898 /* fallback to generic here if not in extents fmt */
Dmitry Monakhov12e9b892010-05-16 22:00:00 -04003899 if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)))
Eric Sandeen6873fa02008-10-07 00:46:36 -04003900 return generic_block_fiemap(inode, fieinfo, start, len,
3901 ext4_get_block);
3902
3903 if (fiemap_check_flags(fieinfo, EXT4_FIEMAP_FLAGS))
3904 return -EBADR;
3905
3906 if (fieinfo->fi_flags & FIEMAP_FLAG_XATTR) {
3907 error = ext4_xattr_fiemap(inode, fieinfo);
3908 } else {
Leonard Michlmayraca92ff2010-03-04 17:07:28 -05003909 ext4_lblk_t len_blks;
3910 __u64 last_blk;
3911
Eric Sandeen6873fa02008-10-07 00:46:36 -04003912 start_blk = start >> inode->i_sb->s_blocksize_bits;
Leonard Michlmayraca92ff2010-03-04 17:07:28 -05003913 last_blk = (start + len - 1) >> inode->i_sb->s_blocksize_bits;
3914 if (last_blk >= EXT_MAX_BLOCK)
3915 last_blk = EXT_MAX_BLOCK-1;
3916 len_blks = ((ext4_lblk_t) last_blk) - start_blk + 1;
Eric Sandeen6873fa02008-10-07 00:46:36 -04003917
3918 /*
3919 * Walk the extent tree gathering extent information.
3920 * ext4_ext_fiemap_cb will push extents back to user.
3921 */
Eric Sandeen6873fa02008-10-07 00:46:36 -04003922 error = ext4_ext_walk_space(inode, start_blk, len_blks,
3923 ext4_ext_fiemap_cb, fieinfo);
Eric Sandeen6873fa02008-10-07 00:46:36 -04003924 }
3925
3926 return error;
3927}
3928