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Artem Bityutskiy1e517642008-07-14 19:08:37 +03001/*
2 * This file is part of UBIFS.
3 *
4 * Copyright (C) 2006-2008 Nokia Corporation.
5 * Copyright (C) 2006, 2007 University of Szeged, Hungary
6 *
7 * This program is free software; you can redistribute it and/or modify it
8 * under the terms of the GNU General Public License version 2 as published by
9 * the Free Software Foundation.
10 *
11 * This program is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
14 * more details.
15 *
16 * You should have received a copy of the GNU General Public License along with
17 * this program; if not, write to the Free Software Foundation, Inc., 51
18 * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
19 *
20 * Authors: Artem Bityutskiy (Битюцкий Артём)
21 * Adrian Hunter
22 * Zoltan Sogor
23 */
24
25/*
26 * This file implements UBIFS I/O subsystem which provides various I/O-related
27 * helper functions (reading/writing/checking/validating nodes) and implements
28 * write-buffering support. Write buffers help to save space which otherwise
29 * would have been wasted for padding to the nearest minimal I/O unit boundary.
30 * Instead, data first goes to the write-buffer and is flushed when the
31 * buffer is full or when it is not used for some time (by timer). This is
Artem Bityutskiy6f7ab6d2009-01-27 16:12:31 +020032 * similar to the mechanism is used by JFFS2.
Artem Bityutskiy1e517642008-07-14 19:08:37 +030033 *
Artem Bityutskiy6c7f74f2011-02-06 14:45:26 +020034 * UBIFS distinguishes between minimum write size (@c->min_io_size) and maximum
35 * write size (@c->max_write_size). The latter is the maximum amount of bytes
36 * the underlying flash is able to program at a time, and writing in
37 * @c->max_write_size units should presumably be faster. Obviously,
38 * @c->min_io_size <= @c->max_write_size. Write-buffers are of
39 * @c->max_write_size bytes in size for maximum performance. However, when a
40 * write-buffer is flushed, only the portion of it (aligned to @c->min_io_size
41 * boundary) which contains data is written, not the whole write-buffer,
42 * because this is more space-efficient.
43 *
44 * This optimization adds few complications to the code. Indeed, on the one
45 * hand, we want to write in optimal @c->max_write_size bytes chunks, which
46 * also means aligning writes at the @c->max_write_size bytes offsets. On the
47 * other hand, we do not want to waste space when synchronizing the write
48 * buffer, so during synchronization we writes in smaller chunks. And this makes
49 * the next write offset to be not aligned to @c->max_write_size bytes. So the
50 * have to make sure that the write-buffer offset (@wbuf->offs) becomes aligned
51 * to @c->max_write_size bytes again. We do this by temporarily shrinking
52 * write-buffer size (@wbuf->size).
53 *
Artem Bityutskiy1e517642008-07-14 19:08:37 +030054 * Write-buffers are defined by 'struct ubifs_wbuf' objects and protected by
55 * mutexes defined inside these objects. Since sometimes upper-level code
56 * has to lock the write-buffer (e.g. journal space reservation code), many
57 * functions related to write-buffers have "nolock" suffix which means that the
58 * caller has to lock the write-buffer before calling this function.
59 *
60 * UBIFS stores nodes at 64 bit-aligned addresses. If the node length is not
61 * aligned, UBIFS starts the next node from the aligned address, and the padded
62 * bytes may contain any rubbish. In other words, UBIFS does not put padding
63 * bytes in those small gaps. Common headers of nodes store real node lengths,
64 * not aligned lengths. Indexing nodes also store real lengths in branches.
65 *
66 * UBIFS uses padding when it pads to the next min. I/O unit. In this case it
67 * uses padding nodes or padding bytes, if the padding node does not fit.
68 *
Artem Bityutskiy6c7f74f2011-02-06 14:45:26 +020069 * All UBIFS nodes are protected by CRC checksums and UBIFS checks CRC when
70 * they are read from the flash media.
Artem Bityutskiy1e517642008-07-14 19:08:37 +030071 */
72
73#include <linux/crc32.h>
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090074#include <linux/slab.h>
Artem Bityutskiy1e517642008-07-14 19:08:37 +030075#include "ubifs.h"
76
77/**
Adrian Hunterff46d7b2008-07-21 15:39:05 +030078 * ubifs_ro_mode - switch UBIFS to read read-only mode.
79 * @c: UBIFS file-system description object
80 * @err: error code which is the reason of switching to R/O mode
81 */
82void ubifs_ro_mode(struct ubifs_info *c, int err)
83{
Artem Bityutskiy2680d722010-09-17 16:44:28 +030084 if (!c->ro_error) {
85 c->ro_error = 1;
Artem Bityutskiyccb3eba2008-09-08 16:07:01 +030086 c->no_chk_data_crc = 0;
ZhangJieJing2fde99c2010-04-16 11:36:50 +080087 c->vfs_sb->s_flags |= MS_RDONLY;
Adrian Hunterff46d7b2008-07-21 15:39:05 +030088 ubifs_warn("switched to read-only mode, error %d", err);
89 dbg_dump_stack();
90 }
91}
92
93/**
Artem Bityutskiy1e517642008-07-14 19:08:37 +030094 * ubifs_check_node - check node.
95 * @c: UBIFS file-system description object
96 * @buf: node to check
97 * @lnum: logical eraseblock number
98 * @offs: offset within the logical eraseblock
99 * @quiet: print no messages
Artem Bityutskiy6f7ab6d2009-01-27 16:12:31 +0200100 * @must_chk_crc: indicates whether to always check the CRC
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300101 *
102 * This function checks node magic number and CRC checksum. This function also
103 * validates node length to prevent UBIFS from becoming crazy when an attacker
104 * feeds it a file-system image with incorrect nodes. For example, too large
105 * node length in the common header could cause UBIFS to read memory outside of
106 * allocated buffer when checking the CRC checksum.
107 *
Artem Bityutskiy6f7ab6d2009-01-27 16:12:31 +0200108 * This function may skip data nodes CRC checking if @c->no_chk_data_crc is
109 * true, which is controlled by corresponding UBIFS mount option. However, if
110 * @must_chk_crc is true, then @c->no_chk_data_crc is ignored and CRC is
Artem Bityutskiy18d1d7f2011-01-17 22:27:56 +0200111 * checked. Similarly, if @c->mounting or @c->remounting_rw is true (we are
112 * mounting or re-mounting to R/W mode), @c->no_chk_data_crc is ignored and CRC
113 * is checked. This is because during mounting or re-mounting from R/O mode to
114 * R/W mode we may read journal nodes (when replying the journal or doing the
115 * recovery) and the journal nodes may potentially be corrupted, so checking is
116 * required.
Artem Bityutskiy6f7ab6d2009-01-27 16:12:31 +0200117 *
118 * This function returns zero in case of success and %-EUCLEAN in case of bad
119 * CRC or magic.
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300120 */
121int ubifs_check_node(const struct ubifs_info *c, const void *buf, int lnum,
Artem Bityutskiy6f7ab6d2009-01-27 16:12:31 +0200122 int offs, int quiet, int must_chk_crc)
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300123{
124 int err = -EINVAL, type, node_len;
125 uint32_t crc, node_crc, magic;
126 const struct ubifs_ch *ch = buf;
127
128 ubifs_assert(lnum >= 0 && lnum < c->leb_cnt && offs >= 0);
129 ubifs_assert(!(offs & 7) && offs < c->leb_size);
130
131 magic = le32_to_cpu(ch->magic);
132 if (magic != UBIFS_NODE_MAGIC) {
133 if (!quiet)
134 ubifs_err("bad magic %#08x, expected %#08x",
135 magic, UBIFS_NODE_MAGIC);
136 err = -EUCLEAN;
137 goto out;
138 }
139
140 type = ch->node_type;
141 if (type < 0 || type >= UBIFS_NODE_TYPES_CNT) {
142 if (!quiet)
143 ubifs_err("bad node type %d", type);
144 goto out;
145 }
146
147 node_len = le32_to_cpu(ch->len);
148 if (node_len + offs > c->leb_size)
149 goto out_len;
150
151 if (c->ranges[type].max_len == 0) {
152 if (node_len != c->ranges[type].len)
153 goto out_len;
154 } else if (node_len < c->ranges[type].min_len ||
155 node_len > c->ranges[type].max_len)
156 goto out_len;
157
Artem Bityutskiy18d1d7f2011-01-17 22:27:56 +0200158 if (!must_chk_crc && type == UBIFS_DATA_NODE && !c->mounting &&
159 !c->remounting_rw && c->no_chk_data_crc)
Artem Bityutskiy6f7ab6d2009-01-27 16:12:31 +0200160 return 0;
Adrian Hunter2953e732008-09-04 16:26:00 +0300161
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300162 crc = crc32(UBIFS_CRC32_INIT, buf + 8, node_len - 8);
163 node_crc = le32_to_cpu(ch->crc);
164 if (crc != node_crc) {
165 if (!quiet)
166 ubifs_err("bad CRC: calculated %#08x, read %#08x",
167 crc, node_crc);
168 err = -EUCLEAN;
169 goto out;
170 }
171
172 return 0;
173
174out_len:
175 if (!quiet)
176 ubifs_err("bad node length %d", node_len);
177out:
178 if (!quiet) {
179 ubifs_err("bad node at LEB %d:%d", lnum, offs);
180 dbg_dump_node(c, buf);
181 dbg_dump_stack();
182 }
183 return err;
184}
185
186/**
187 * ubifs_pad - pad flash space.
188 * @c: UBIFS file-system description object
189 * @buf: buffer to put padding to
190 * @pad: how many bytes to pad
191 *
192 * The flash media obliges us to write only in chunks of %c->min_io_size and
193 * when we have to write less data we add padding node to the write-buffer and
194 * pad it to the next minimal I/O unit's boundary. Padding nodes help when the
195 * media is being scanned. If the amount of wasted space is not enough to fit a
196 * padding node which takes %UBIFS_PAD_NODE_SZ bytes, we write padding bytes
197 * pattern (%UBIFS_PADDING_BYTE).
198 *
199 * Padding nodes are also used to fill gaps when the "commit-in-gaps" method is
200 * used.
201 */
202void ubifs_pad(const struct ubifs_info *c, void *buf, int pad)
203{
204 uint32_t crc;
205
206 ubifs_assert(pad >= 0 && !(pad & 7));
207
208 if (pad >= UBIFS_PAD_NODE_SZ) {
209 struct ubifs_ch *ch = buf;
210 struct ubifs_pad_node *pad_node = buf;
211
212 ch->magic = cpu_to_le32(UBIFS_NODE_MAGIC);
213 ch->node_type = UBIFS_PAD_NODE;
214 ch->group_type = UBIFS_NO_NODE_GROUP;
215 ch->padding[0] = ch->padding[1] = 0;
216 ch->sqnum = 0;
217 ch->len = cpu_to_le32(UBIFS_PAD_NODE_SZ);
218 pad -= UBIFS_PAD_NODE_SZ;
219 pad_node->pad_len = cpu_to_le32(pad);
220 crc = crc32(UBIFS_CRC32_INIT, buf + 8, UBIFS_PAD_NODE_SZ - 8);
221 ch->crc = cpu_to_le32(crc);
222 memset(buf + UBIFS_PAD_NODE_SZ, 0, pad);
223 } else if (pad > 0)
224 /* Too little space, padding node won't fit */
225 memset(buf, UBIFS_PADDING_BYTE, pad);
226}
227
228/**
229 * next_sqnum - get next sequence number.
230 * @c: UBIFS file-system description object
231 */
232static unsigned long long next_sqnum(struct ubifs_info *c)
233{
234 unsigned long long sqnum;
235
236 spin_lock(&c->cnt_lock);
237 sqnum = ++c->max_sqnum;
238 spin_unlock(&c->cnt_lock);
239
240 if (unlikely(sqnum >= SQNUM_WARN_WATERMARK)) {
241 if (sqnum >= SQNUM_WATERMARK) {
242 ubifs_err("sequence number overflow %llu, end of life",
243 sqnum);
244 ubifs_ro_mode(c, -EINVAL);
245 }
246 ubifs_warn("running out of sequence numbers, end of life soon");
247 }
248
249 return sqnum;
250}
251
252/**
253 * ubifs_prepare_node - prepare node to be written to flash.
254 * @c: UBIFS file-system description object
255 * @node: the node to pad
256 * @len: node length
257 * @pad: if the buffer has to be padded
258 *
259 * This function prepares node at @node to be written to the media - it
260 * calculates node CRC, fills the common header, and adds proper padding up to
261 * the next minimum I/O unit if @pad is not zero.
262 */
263void ubifs_prepare_node(struct ubifs_info *c, void *node, int len, int pad)
264{
265 uint32_t crc;
266 struct ubifs_ch *ch = node;
267 unsigned long long sqnum = next_sqnum(c);
268
269 ubifs_assert(len >= UBIFS_CH_SZ);
270
271 ch->magic = cpu_to_le32(UBIFS_NODE_MAGIC);
272 ch->len = cpu_to_le32(len);
273 ch->group_type = UBIFS_NO_NODE_GROUP;
274 ch->sqnum = cpu_to_le64(sqnum);
275 ch->padding[0] = ch->padding[1] = 0;
276 crc = crc32(UBIFS_CRC32_INIT, node + 8, len - 8);
277 ch->crc = cpu_to_le32(crc);
278
279 if (pad) {
280 len = ALIGN(len, 8);
281 pad = ALIGN(len, c->min_io_size) - len;
282 ubifs_pad(c, node + len, pad);
283 }
284}
285
286/**
287 * ubifs_prep_grp_node - prepare node of a group to be written to flash.
288 * @c: UBIFS file-system description object
289 * @node: the node to pad
290 * @len: node length
291 * @last: indicates the last node of the group
292 *
293 * This function prepares node at @node to be written to the media - it
294 * calculates node CRC and fills the common header.
295 */
296void ubifs_prep_grp_node(struct ubifs_info *c, void *node, int len, int last)
297{
298 uint32_t crc;
299 struct ubifs_ch *ch = node;
300 unsigned long long sqnum = next_sqnum(c);
301
302 ubifs_assert(len >= UBIFS_CH_SZ);
303
304 ch->magic = cpu_to_le32(UBIFS_NODE_MAGIC);
305 ch->len = cpu_to_le32(len);
306 if (last)
307 ch->group_type = UBIFS_LAST_OF_NODE_GROUP;
308 else
309 ch->group_type = UBIFS_IN_NODE_GROUP;
310 ch->sqnum = cpu_to_le64(sqnum);
311 ch->padding[0] = ch->padding[1] = 0;
312 crc = crc32(UBIFS_CRC32_INIT, node + 8, len - 8);
313 ch->crc = cpu_to_le32(crc);
314}
315
316/**
317 * wbuf_timer_callback - write-buffer timer callback function.
318 * @data: timer data (write-buffer descriptor)
319 *
320 * This function is called when the write-buffer timer expires.
321 */
Artem Bityutskiyf2c5dbd2009-05-28 16:24:15 +0300322static enum hrtimer_restart wbuf_timer_callback_nolock(struct hrtimer *timer)
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300323{
Artem Bityutskiyf2c5dbd2009-05-28 16:24:15 +0300324 struct ubifs_wbuf *wbuf = container_of(timer, struct ubifs_wbuf, timer);
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300325
Artem Bityutskiy77a7ae52009-09-15 15:03:51 +0300326 dbg_io("jhead %s", dbg_jhead(wbuf->jhead));
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300327 wbuf->need_sync = 1;
328 wbuf->c->need_wbuf_sync = 1;
329 ubifs_wake_up_bgt(wbuf->c);
Artem Bityutskiyf2c5dbd2009-05-28 16:24:15 +0300330 return HRTIMER_NORESTART;
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300331}
332
333/**
334 * new_wbuf_timer - start new write-buffer timer.
335 * @wbuf: write-buffer descriptor
336 */
337static void new_wbuf_timer_nolock(struct ubifs_wbuf *wbuf)
338{
Artem Bityutskiyf2c5dbd2009-05-28 16:24:15 +0300339 ubifs_assert(!hrtimer_active(&wbuf->timer));
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300340
Artem Bityutskiy0b335b92009-06-23 12:30:43 +0300341 if (wbuf->no_timer)
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300342 return;
Artem Bityutskiy77a7ae52009-09-15 15:03:51 +0300343 dbg_io("set timer for jhead %s, %llu-%llu millisecs",
344 dbg_jhead(wbuf->jhead),
Adrian Hunter44737582009-06-24 10:15:12 +0300345 div_u64(ktime_to_ns(wbuf->softlimit), USEC_PER_SEC),
346 div_u64(ktime_to_ns(wbuf->softlimit) + wbuf->delta,
347 USEC_PER_SEC));
Artem Bityutskiyf2c5dbd2009-05-28 16:24:15 +0300348 hrtimer_start_range_ns(&wbuf->timer, wbuf->softlimit, wbuf->delta,
349 HRTIMER_MODE_REL);
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300350}
351
352/**
353 * cancel_wbuf_timer - cancel write-buffer timer.
354 * @wbuf: write-buffer descriptor
355 */
356static void cancel_wbuf_timer_nolock(struct ubifs_wbuf *wbuf)
357{
Artem Bityutskiy0b335b92009-06-23 12:30:43 +0300358 if (wbuf->no_timer)
359 return;
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300360 wbuf->need_sync = 0;
Artem Bityutskiyf2c5dbd2009-05-28 16:24:15 +0300361 hrtimer_cancel(&wbuf->timer);
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300362}
363
364/**
365 * ubifs_wbuf_sync_nolock - synchronize write-buffer.
366 * @wbuf: write-buffer to synchronize
367 *
368 * This function synchronizes write-buffer @buf and returns zero in case of
369 * success or a negative error code in case of failure.
Artem Bityutskiy6c7f74f2011-02-06 14:45:26 +0200370 *
371 * Note, although write-buffers are of @c->max_write_size, this function does
372 * not necessarily writes all @c->max_write_size bytes to the flash. Instead,
373 * if the write-buffer is only partially filled with data, only the used part
374 * of the write-buffer (aligned on @c->min_io_size boundary) is synchronized.
375 * This way we waste less space.
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300376 */
377int ubifs_wbuf_sync_nolock(struct ubifs_wbuf *wbuf)
378{
379 struct ubifs_info *c = wbuf->c;
Artem Bityutskiy6c7f74f2011-02-06 14:45:26 +0200380 int err, dirt, sync_len;
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300381
382 cancel_wbuf_timer_nolock(wbuf);
383 if (!wbuf->used || wbuf->lnum == -1)
384 /* Write-buffer is empty or not seeked */
385 return 0;
386
Artem Bityutskiy77a7ae52009-09-15 15:03:51 +0300387 dbg_io("LEB %d:%d, %d bytes, jhead %s",
388 wbuf->lnum, wbuf->offs, wbuf->used, dbg_jhead(wbuf->jhead));
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300389 ubifs_assert(!(wbuf->avail & 7));
Artem Bityutskiy3c89f392011-02-01 19:02:49 +0200390 ubifs_assert(wbuf->offs + wbuf->size <= c->leb_size);
391 ubifs_assert(wbuf->size >= c->min_io_size);
392 ubifs_assert(wbuf->size <= c->max_write_size);
393 ubifs_assert(wbuf->size % c->min_io_size == 0);
Artem Bityutskiy2ef13292010-09-19 18:34:26 +0300394 ubifs_assert(!c->ro_media && !c->ro_mount);
Artem Bityutskiy6c7f74f2011-02-06 14:45:26 +0200395 if (c->leb_size - wbuf->offs >= c->max_write_size)
Artem Bityutskiyc4361572011-03-25 15:27:40 +0200396 ubifs_assert(!((wbuf->offs + wbuf->size) % c->max_write_size));
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300397
Artem Bityutskiy2680d722010-09-17 16:44:28 +0300398 if (c->ro_error)
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300399 return -EROFS;
400
Artem Bityutskiy6c7f74f2011-02-06 14:45:26 +0200401 /*
402 * Do not write whole write buffer but write only the minimum necessary
403 * amount of min. I/O units.
404 */
405 sync_len = ALIGN(wbuf->used, c->min_io_size);
406 dirt = sync_len - wbuf->used;
407 if (dirt)
408 ubifs_pad(c, wbuf->buf + wbuf->used, dirt);
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300409 err = ubi_leb_write(c->ubi, wbuf->lnum, wbuf->buf, wbuf->offs,
Artem Bityutskiy6c7f74f2011-02-06 14:45:26 +0200410 sync_len, wbuf->dtype);
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300411 if (err) {
412 ubifs_err("cannot write %d bytes to LEB %d:%d",
Artem Bityutskiy6c7f74f2011-02-06 14:45:26 +0200413 sync_len, wbuf->lnum, wbuf->offs);
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300414 dbg_dump_stack();
415 return err;
416 }
417
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300418 spin_lock(&wbuf->lock);
Artem Bityutskiy6c7f74f2011-02-06 14:45:26 +0200419 wbuf->offs += sync_len;
420 /*
421 * Now @wbuf->offs is not necessarily aligned to @c->max_write_size.
422 * But our goal is to optimize writes and make sure we write in
423 * @c->max_write_size chunks and to @c->max_write_size-aligned offset.
424 * Thus, if @wbuf->offs is not aligned to @c->max_write_size now, make
425 * sure that @wbuf->offs + @wbuf->size is aligned to
426 * @c->max_write_size. This way we make sure that after next
427 * write-buffer flush we are again at the optimal offset (aligned to
428 * @c->max_write_size).
429 */
430 if (c->leb_size - wbuf->offs < c->max_write_size)
431 wbuf->size = c->leb_size - wbuf->offs;
432 else if (wbuf->offs & (c->max_write_size - 1))
433 wbuf->size = ALIGN(wbuf->offs, c->max_write_size) - wbuf->offs;
434 else
435 wbuf->size = c->max_write_size;
436 wbuf->avail = wbuf->size;
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300437 wbuf->used = 0;
438 wbuf->next_ino = 0;
439 spin_unlock(&wbuf->lock);
440
441 if (wbuf->sync_callback)
442 err = wbuf->sync_callback(c, wbuf->lnum,
443 c->leb_size - wbuf->offs, dirt);
444 return err;
445}
446
447/**
448 * ubifs_wbuf_seek_nolock - seek write-buffer.
449 * @wbuf: write-buffer
450 * @lnum: logical eraseblock number to seek to
451 * @offs: logical eraseblock offset to seek to
452 * @dtype: data type
453 *
Artem Bityutskiycb54ef82009-06-23 20:30:32 +0300454 * This function targets the write-buffer to logical eraseblock @lnum:@offs.
Artem Bityutskiycb14a182011-05-15 14:51:54 +0300455 * The write-buffer has to be empty. Returns zero in case of success and a
456 * negative error code in case of failure.
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300457 */
458int ubifs_wbuf_seek_nolock(struct ubifs_wbuf *wbuf, int lnum, int offs,
459 int dtype)
460{
461 const struct ubifs_info *c = wbuf->c;
462
Artem Bityutskiy77a7ae52009-09-15 15:03:51 +0300463 dbg_io("LEB %d:%d, jhead %s", lnum, offs, dbg_jhead(wbuf->jhead));
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300464 ubifs_assert(lnum >= 0 && lnum < c->leb_cnt);
465 ubifs_assert(offs >= 0 && offs <= c->leb_size);
466 ubifs_assert(offs % c->min_io_size == 0 && !(offs & 7));
467 ubifs_assert(lnum != wbuf->lnum);
Artem Bityutskiycb14a182011-05-15 14:51:54 +0300468 ubifs_assert(wbuf->used == 0);
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300469
470 spin_lock(&wbuf->lock);
471 wbuf->lnum = lnum;
472 wbuf->offs = offs;
Artem Bityutskiy6c7f74f2011-02-06 14:45:26 +0200473 if (c->leb_size - wbuf->offs < c->max_write_size)
474 wbuf->size = c->leb_size - wbuf->offs;
475 else if (wbuf->offs & (c->max_write_size - 1))
476 wbuf->size = ALIGN(wbuf->offs, c->max_write_size) - wbuf->offs;
477 else
478 wbuf->size = c->max_write_size;
479 wbuf->avail = wbuf->size;
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300480 wbuf->used = 0;
481 spin_unlock(&wbuf->lock);
482 wbuf->dtype = dtype;
483
484 return 0;
485}
486
487/**
488 * ubifs_bg_wbufs_sync - synchronize write-buffers.
489 * @c: UBIFS file-system description object
490 *
491 * This function is called by background thread to synchronize write-buffers.
492 * Returns zero in case of success and a negative error code in case of
493 * failure.
494 */
495int ubifs_bg_wbufs_sync(struct ubifs_info *c)
496{
497 int err, i;
498
Artem Bityutskiy2ef13292010-09-19 18:34:26 +0300499 ubifs_assert(!c->ro_media && !c->ro_mount);
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300500 if (!c->need_wbuf_sync)
501 return 0;
502 c->need_wbuf_sync = 0;
503
Artem Bityutskiy2680d722010-09-17 16:44:28 +0300504 if (c->ro_error) {
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300505 err = -EROFS;
506 goto out_timers;
507 }
508
509 dbg_io("synchronize");
510 for (i = 0; i < c->jhead_cnt; i++) {
511 struct ubifs_wbuf *wbuf = &c->jheads[i].wbuf;
512
513 cond_resched();
514
515 /*
516 * If the mutex is locked then wbuf is being changed, so
517 * synchronization is not necessary.
518 */
519 if (mutex_is_locked(&wbuf->io_mutex))
520 continue;
521
522 mutex_lock_nested(&wbuf->io_mutex, wbuf->jhead);
523 if (!wbuf->need_sync) {
524 mutex_unlock(&wbuf->io_mutex);
525 continue;
526 }
527
528 err = ubifs_wbuf_sync_nolock(wbuf);
529 mutex_unlock(&wbuf->io_mutex);
530 if (err) {
531 ubifs_err("cannot sync write-buffer, error %d", err);
532 ubifs_ro_mode(c, err);
533 goto out_timers;
534 }
535 }
536
537 return 0;
538
539out_timers:
540 /* Cancel all timers to prevent repeated errors */
541 for (i = 0; i < c->jhead_cnt; i++) {
542 struct ubifs_wbuf *wbuf = &c->jheads[i].wbuf;
543
544 mutex_lock_nested(&wbuf->io_mutex, wbuf->jhead);
545 cancel_wbuf_timer_nolock(wbuf);
546 mutex_unlock(&wbuf->io_mutex);
547 }
548 return err;
549}
550
551/**
552 * ubifs_wbuf_write_nolock - write data to flash via write-buffer.
553 * @wbuf: write-buffer
554 * @buf: node to write
555 * @len: node length
556 *
557 * This function writes data to flash via write-buffer @wbuf. This means that
558 * the last piece of the node won't reach the flash media immediately if it
Artem Bityutskiy6c7f74f2011-02-06 14:45:26 +0200559 * does not take whole max. write unit (@c->max_write_size). Instead, the node
560 * will sit in RAM until the write-buffer is synchronized (e.g., by timer, or
561 * because more data are appended to the write-buffer).
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300562 *
563 * This function returns zero in case of success and a negative error code in
564 * case of failure. If the node cannot be written because there is no more
565 * space in this logical eraseblock, %-ENOSPC is returned.
566 */
567int ubifs_wbuf_write_nolock(struct ubifs_wbuf *wbuf, void *buf, int len)
568{
569 struct ubifs_info *c = wbuf->c;
Artem Bityutskiy12f33892011-05-14 17:37:47 +0300570 int err, written, n, aligned_len = ALIGN(len, 8);
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300571
Artem Bityutskiy77a7ae52009-09-15 15:03:51 +0300572 dbg_io("%d bytes (%s) to jhead %s wbuf at LEB %d:%d", len,
573 dbg_ntype(((struct ubifs_ch *)buf)->node_type),
574 dbg_jhead(wbuf->jhead), wbuf->lnum, wbuf->offs + wbuf->used);
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300575 ubifs_assert(len > 0 && wbuf->lnum >= 0 && wbuf->lnum < c->leb_cnt);
576 ubifs_assert(wbuf->offs >= 0 && wbuf->offs % c->min_io_size == 0);
577 ubifs_assert(!(wbuf->offs & 7) && wbuf->offs <= c->leb_size);
Artem Bityutskiy3c89f392011-02-01 19:02:49 +0200578 ubifs_assert(wbuf->avail > 0 && wbuf->avail <= wbuf->size);
579 ubifs_assert(wbuf->size >= c->min_io_size);
580 ubifs_assert(wbuf->size <= c->max_write_size);
581 ubifs_assert(wbuf->size % c->min_io_size == 0);
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300582 ubifs_assert(mutex_is_locked(&wbuf->io_mutex));
Artem Bityutskiy2ef13292010-09-19 18:34:26 +0300583 ubifs_assert(!c->ro_media && !c->ro_mount);
Ben Gardiner4f1ab9b2011-05-30 14:56:14 -0400584 ubifs_assert(!c->space_fixup);
Artem Bityutskiy6c7f74f2011-02-06 14:45:26 +0200585 if (c->leb_size - wbuf->offs >= c->max_write_size)
Artem Bityutskiyc4361572011-03-25 15:27:40 +0200586 ubifs_assert(!((wbuf->offs + wbuf->size) % c->max_write_size));
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300587
588 if (c->leb_size - wbuf->offs - wbuf->used < aligned_len) {
589 err = -ENOSPC;
590 goto out;
591 }
592
593 cancel_wbuf_timer_nolock(wbuf);
594
Artem Bityutskiy2680d722010-09-17 16:44:28 +0300595 if (c->ro_error)
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300596 return -EROFS;
597
598 if (aligned_len <= wbuf->avail) {
599 /*
600 * The node is not very large and fits entirely within
601 * write-buffer.
602 */
603 memcpy(wbuf->buf + wbuf->used, buf, len);
604
605 if (aligned_len == wbuf->avail) {
Artem Bityutskiy77a7ae52009-09-15 15:03:51 +0300606 dbg_io("flush jhead %s wbuf to LEB %d:%d",
607 dbg_jhead(wbuf->jhead), wbuf->lnum, wbuf->offs);
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300608 err = ubi_leb_write(c->ubi, wbuf->lnum, wbuf->buf,
Artem Bityutskiy3c89f392011-02-01 19:02:49 +0200609 wbuf->offs, wbuf->size,
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300610 wbuf->dtype);
611 if (err)
612 goto out;
613
614 spin_lock(&wbuf->lock);
Artem Bityutskiy6c7f74f2011-02-06 14:45:26 +0200615 wbuf->offs += wbuf->size;
616 if (c->leb_size - wbuf->offs >= c->max_write_size)
617 wbuf->size = c->max_write_size;
618 else
619 wbuf->size = c->leb_size - wbuf->offs;
620 wbuf->avail = wbuf->size;
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300621 wbuf->used = 0;
622 wbuf->next_ino = 0;
623 spin_unlock(&wbuf->lock);
624 } else {
625 spin_lock(&wbuf->lock);
626 wbuf->avail -= aligned_len;
627 wbuf->used += aligned_len;
628 spin_unlock(&wbuf->lock);
629 }
630
631 goto exit;
632 }
633
Artem Bityutskiy6c7f74f2011-02-06 14:45:26 +0200634 written = 0;
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300635
Artem Bityutskiy6c7f74f2011-02-06 14:45:26 +0200636 if (wbuf->used) {
637 /*
638 * The node is large enough and does not fit entirely within
639 * current available space. We have to fill and flush
640 * write-buffer and switch to the next max. write unit.
641 */
642 dbg_io("flush jhead %s wbuf to LEB %d:%d",
643 dbg_jhead(wbuf->jhead), wbuf->lnum, wbuf->offs);
644 memcpy(wbuf->buf + wbuf->used, buf, wbuf->avail);
645 err = ubi_leb_write(c->ubi, wbuf->lnum, wbuf->buf, wbuf->offs,
646 wbuf->size, wbuf->dtype);
647 if (err)
648 goto out;
649
Artem Bityutskiy12f33892011-05-14 17:37:47 +0300650 wbuf->offs += wbuf->size;
Artem Bityutskiy6c7f74f2011-02-06 14:45:26 +0200651 len -= wbuf->avail;
652 aligned_len -= wbuf->avail;
653 written += wbuf->avail;
654 } else if (wbuf->offs & (c->max_write_size - 1)) {
655 /*
656 * The write-buffer offset is not aligned to
657 * @c->max_write_size and @wbuf->size is less than
658 * @c->max_write_size. Write @wbuf->size bytes to make sure the
659 * following writes are done in optimal @c->max_write_size
660 * chunks.
661 */
662 dbg_io("write %d bytes to LEB %d:%d",
663 wbuf->size, wbuf->lnum, wbuf->offs);
664 err = ubi_leb_write(c->ubi, wbuf->lnum, buf, wbuf->offs,
665 wbuf->size, wbuf->dtype);
666 if (err)
667 goto out;
668
Artem Bityutskiy12f33892011-05-14 17:37:47 +0300669 wbuf->offs += wbuf->size;
Artem Bityutskiy6c7f74f2011-02-06 14:45:26 +0200670 len -= wbuf->size;
671 aligned_len -= wbuf->size;
672 written += wbuf->size;
673 }
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300674
675 /*
Artem Bityutskiy6c7f74f2011-02-06 14:45:26 +0200676 * The remaining data may take more whole max. write units, so write the
677 * remains multiple to max. write unit size directly to the flash media.
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300678 * We align node length to 8-byte boundary because we anyway flash wbuf
679 * if the remaining space is less than 8 bytes.
680 */
Artem Bityutskiy6c7f74f2011-02-06 14:45:26 +0200681 n = aligned_len >> c->max_write_shift;
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300682 if (n) {
Artem Bityutskiy6c7f74f2011-02-06 14:45:26 +0200683 n <<= c->max_write_shift;
Artem Bityutskiy12f33892011-05-14 17:37:47 +0300684 dbg_io("write %d bytes to LEB %d:%d", n, wbuf->lnum,
685 wbuf->offs);
686 err = ubi_leb_write(c->ubi, wbuf->lnum, buf + written,
687 wbuf->offs, n, wbuf->dtype);
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300688 if (err)
689 goto out;
Artem Bityutskiy12f33892011-05-14 17:37:47 +0300690 wbuf->offs += n;
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300691 aligned_len -= n;
692 len -= n;
693 written += n;
694 }
695
696 spin_lock(&wbuf->lock);
697 if (aligned_len)
698 /*
699 * And now we have what's left and what does not take whole
Artem Bityutskiy6c7f74f2011-02-06 14:45:26 +0200700 * max. write unit, so write it to the write-buffer and we are
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300701 * done.
702 */
703 memcpy(wbuf->buf, buf + written, len);
704
Artem Bityutskiy6c7f74f2011-02-06 14:45:26 +0200705 if (c->leb_size - wbuf->offs >= c->max_write_size)
706 wbuf->size = c->max_write_size;
707 else
708 wbuf->size = c->leb_size - wbuf->offs;
709 wbuf->avail = wbuf->size - aligned_len;
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300710 wbuf->used = aligned_len;
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300711 wbuf->next_ino = 0;
712 spin_unlock(&wbuf->lock);
713
714exit:
715 if (wbuf->sync_callback) {
716 int free = c->leb_size - wbuf->offs - wbuf->used;
717
718 err = wbuf->sync_callback(c, wbuf->lnum, free, 0);
719 if (err)
720 goto out;
721 }
722
723 if (wbuf->used)
724 new_wbuf_timer_nolock(wbuf);
725
726 return 0;
727
728out:
729 ubifs_err("cannot write %d bytes to LEB %d:%d, error %d",
730 len, wbuf->lnum, wbuf->offs, err);
731 dbg_dump_node(c, buf);
732 dbg_dump_stack();
733 dbg_dump_leb(c, wbuf->lnum);
734 return err;
735}
736
737/**
738 * ubifs_write_node - write node to the media.
739 * @c: UBIFS file-system description object
740 * @buf: the node to write
741 * @len: node length
742 * @lnum: logical eraseblock number
743 * @offs: offset within the logical eraseblock
744 * @dtype: node life-time hint (%UBI_LONGTERM, %UBI_SHORTTERM, %UBI_UNKNOWN)
745 *
746 * This function automatically fills node magic number, assigns sequence
747 * number, and calculates node CRC checksum. The length of the @buf buffer has
748 * to be aligned to the minimal I/O unit size. This function automatically
749 * appends padding node and padding bytes if needed. Returns zero in case of
750 * success and a negative error code in case of failure.
751 */
752int ubifs_write_node(struct ubifs_info *c, void *buf, int len, int lnum,
753 int offs, int dtype)
754{
755 int err, buf_len = ALIGN(len, c->min_io_size);
756
757 dbg_io("LEB %d:%d, %s, length %d (aligned %d)",
758 lnum, offs, dbg_ntype(((struct ubifs_ch *)buf)->node_type), len,
759 buf_len);
760 ubifs_assert(lnum >= 0 && lnum < c->leb_cnt && offs >= 0);
761 ubifs_assert(offs % c->min_io_size == 0 && offs < c->leb_size);
Artem Bityutskiy2ef13292010-09-19 18:34:26 +0300762 ubifs_assert(!c->ro_media && !c->ro_mount);
Ben Gardiner4f1ab9b2011-05-30 14:56:14 -0400763 ubifs_assert(!c->space_fixup);
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300764
Artem Bityutskiy2680d722010-09-17 16:44:28 +0300765 if (c->ro_error)
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300766 return -EROFS;
767
768 ubifs_prepare_node(c, buf, len, 1);
769 err = ubi_leb_write(c->ubi, lnum, buf, offs, buf_len, dtype);
770 if (err) {
771 ubifs_err("cannot write %d bytes to LEB %d:%d, error %d",
772 buf_len, lnum, offs, err);
773 dbg_dump_node(c, buf);
774 dbg_dump_stack();
775 }
776
777 return err;
778}
779
780/**
781 * ubifs_read_node_wbuf - read node from the media or write-buffer.
782 * @wbuf: wbuf to check for un-written data
783 * @buf: buffer to read to
784 * @type: node type
785 * @len: node length
786 * @lnum: logical eraseblock number
787 * @offs: offset within the logical eraseblock
788 *
789 * This function reads a node of known type and length, checks it and stores
790 * in @buf. If the node partially or fully sits in the write-buffer, this
791 * function takes data from the buffer, otherwise it reads the flash media.
792 * Returns zero in case of success, %-EUCLEAN if CRC mismatched and a negative
793 * error code in case of failure.
794 */
795int ubifs_read_node_wbuf(struct ubifs_wbuf *wbuf, void *buf, int type, int len,
796 int lnum, int offs)
797{
798 const struct ubifs_info *c = wbuf->c;
799 int err, rlen, overlap;
800 struct ubifs_ch *ch = buf;
801
Artem Bityutskiy77a7ae52009-09-15 15:03:51 +0300802 dbg_io("LEB %d:%d, %s, length %d, jhead %s", lnum, offs,
803 dbg_ntype(type), len, dbg_jhead(wbuf->jhead));
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300804 ubifs_assert(wbuf && lnum >= 0 && lnum < c->leb_cnt && offs >= 0);
805 ubifs_assert(!(offs & 7) && offs < c->leb_size);
806 ubifs_assert(type >= 0 && type < UBIFS_NODE_TYPES_CNT);
807
808 spin_lock(&wbuf->lock);
809 overlap = (lnum == wbuf->lnum && offs + len > wbuf->offs);
810 if (!overlap) {
811 /* We may safely unlock the write-buffer and read the data */
812 spin_unlock(&wbuf->lock);
813 return ubifs_read_node(c, buf, type, len, lnum, offs);
814 }
815
816 /* Don't read under wbuf */
817 rlen = wbuf->offs - offs;
818 if (rlen < 0)
819 rlen = 0;
820
821 /* Copy the rest from the write-buffer */
822 memcpy(buf + rlen, wbuf->buf + offs + rlen - wbuf->offs, len - rlen);
823 spin_unlock(&wbuf->lock);
824
825 if (rlen > 0) {
826 /* Read everything that goes before write-buffer */
827 err = ubi_read(c->ubi, lnum, buf, offs, rlen);
828 if (err && err != -EBADMSG) {
829 ubifs_err("failed to read node %d from LEB %d:%d, "
830 "error %d", type, lnum, offs, err);
831 dbg_dump_stack();
832 return err;
833 }
834 }
835
836 if (type != ch->node_type) {
837 ubifs_err("bad node type (%d but expected %d)",
838 ch->node_type, type);
839 goto out;
840 }
841
Adrian Hunter2953e732008-09-04 16:26:00 +0300842 err = ubifs_check_node(c, buf, lnum, offs, 0, 0);
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300843 if (err) {
844 ubifs_err("expected node type %d", type);
845 return err;
846 }
847
848 rlen = le32_to_cpu(ch->len);
849 if (rlen != len) {
850 ubifs_err("bad node length %d, expected %d", rlen, len);
851 goto out;
852 }
853
854 return 0;
855
856out:
857 ubifs_err("bad node at LEB %d:%d", lnum, offs);
858 dbg_dump_node(c, buf);
859 dbg_dump_stack();
860 return -EINVAL;
861}
862
863/**
864 * ubifs_read_node - read node.
865 * @c: UBIFS file-system description object
866 * @buf: buffer to read to
867 * @type: node type
868 * @len: node length (not aligned)
869 * @lnum: logical eraseblock number
870 * @offs: offset within the logical eraseblock
871 *
872 * This function reads a node of known type and and length, checks it and
873 * stores in @buf. Returns zero in case of success, %-EUCLEAN if CRC mismatched
874 * and a negative error code in case of failure.
875 */
876int ubifs_read_node(const struct ubifs_info *c, void *buf, int type, int len,
877 int lnum, int offs)
878{
879 int err, l;
880 struct ubifs_ch *ch = buf;
881
882 dbg_io("LEB %d:%d, %s, length %d", lnum, offs, dbg_ntype(type), len);
883 ubifs_assert(lnum >= 0 && lnum < c->leb_cnt && offs >= 0);
884 ubifs_assert(len >= UBIFS_CH_SZ && offs + len <= c->leb_size);
885 ubifs_assert(!(offs & 7) && offs < c->leb_size);
886 ubifs_assert(type >= 0 && type < UBIFS_NODE_TYPES_CNT);
887
888 err = ubi_read(c->ubi, lnum, buf, offs, len);
889 if (err && err != -EBADMSG) {
890 ubifs_err("cannot read node %d from LEB %d:%d, error %d",
891 type, lnum, offs, err);
892 return err;
893 }
894
895 if (type != ch->node_type) {
896 ubifs_err("bad node type (%d but expected %d)",
897 ch->node_type, type);
898 goto out;
899 }
900
Adrian Hunter2953e732008-09-04 16:26:00 +0300901 err = ubifs_check_node(c, buf, lnum, offs, 0, 0);
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300902 if (err) {
903 ubifs_err("expected node type %d", type);
904 return err;
905 }
906
907 l = le32_to_cpu(ch->len);
908 if (l != len) {
909 ubifs_err("bad node length %d, expected %d", l, len);
910 goto out;
911 }
912
913 return 0;
914
915out:
Artem Bityutskiy3a8fa0e2010-08-22 21:27:30 +0300916 ubifs_err("bad node at LEB %d:%d, LEB mapping status %d", lnum, offs,
917 ubi_is_mapped(c->ubi, lnum));
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300918 dbg_dump_node(c, buf);
919 dbg_dump_stack();
920 return -EINVAL;
921}
922
923/**
924 * ubifs_wbuf_init - initialize write-buffer.
925 * @c: UBIFS file-system description object
926 * @wbuf: write-buffer to initialize
927 *
Artem Bityutskiycb54ef82009-06-23 20:30:32 +0300928 * This function initializes write-buffer. Returns zero in case of success
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300929 * %-ENOMEM in case of failure.
930 */
931int ubifs_wbuf_init(struct ubifs_info *c, struct ubifs_wbuf *wbuf)
932{
933 size_t size;
934
Artem Bityutskiy6c7f74f2011-02-06 14:45:26 +0200935 wbuf->buf = kmalloc(c->max_write_size, GFP_KERNEL);
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300936 if (!wbuf->buf)
937 return -ENOMEM;
938
Artem Bityutskiy6c7f74f2011-02-06 14:45:26 +0200939 size = (c->max_write_size / UBIFS_CH_SZ + 1) * sizeof(ino_t);
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300940 wbuf->inodes = kmalloc(size, GFP_KERNEL);
941 if (!wbuf->inodes) {
942 kfree(wbuf->buf);
943 wbuf->buf = NULL;
944 return -ENOMEM;
945 }
946
947 wbuf->used = 0;
948 wbuf->lnum = wbuf->offs = -1;
Artem Bityutskiy6c7f74f2011-02-06 14:45:26 +0200949 /*
950 * If the LEB starts at the max. write size aligned address, then
951 * write-buffer size has to be set to @c->max_write_size. Otherwise,
952 * set it to something smaller so that it ends at the closest max.
953 * write size boundary.
954 */
955 size = c->max_write_size - (c->leb_start % c->max_write_size);
956 wbuf->avail = wbuf->size = size;
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300957 wbuf->dtype = UBI_UNKNOWN;
958 wbuf->sync_callback = NULL;
959 mutex_init(&wbuf->io_mutex);
960 spin_lock_init(&wbuf->lock);
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300961 wbuf->c = c;
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300962 wbuf->next_ino = 0;
963
Artem Bityutskiyf2c5dbd2009-05-28 16:24:15 +0300964 hrtimer_init(&wbuf->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
965 wbuf->timer.function = wbuf_timer_callback_nolock;
Artem Bityutskiy2a35a3a82009-06-23 20:26:33 +0300966 wbuf->softlimit = ktime_set(WBUF_TIMEOUT_SOFTLIMIT, 0);
967 wbuf->delta = WBUF_TIMEOUT_HARDLIMIT - WBUF_TIMEOUT_SOFTLIMIT;
968 wbuf->delta *= 1000000000ULL;
969 ubifs_assert(wbuf->delta <= ULONG_MAX);
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300970 return 0;
971}
972
973/**
974 * ubifs_wbuf_add_ino_nolock - add an inode number into the wbuf inode array.
Artem Bityutskiycb54ef82009-06-23 20:30:32 +0300975 * @wbuf: the write-buffer where to add
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300976 * @inum: the inode number
977 *
978 * This function adds an inode number to the inode array of the write-buffer.
979 */
980void ubifs_wbuf_add_ino_nolock(struct ubifs_wbuf *wbuf, ino_t inum)
981{
982 if (!wbuf->buf)
983 /* NOR flash or something similar */
984 return;
985
986 spin_lock(&wbuf->lock);
987 if (wbuf->used)
988 wbuf->inodes[wbuf->next_ino++] = inum;
989 spin_unlock(&wbuf->lock);
990}
991
992/**
993 * wbuf_has_ino - returns if the wbuf contains data from the inode.
994 * @wbuf: the write-buffer
995 * @inum: the inode number
996 *
997 * This function returns with %1 if the write-buffer contains some data from the
998 * given inode otherwise it returns with %0.
999 */
1000static int wbuf_has_ino(struct ubifs_wbuf *wbuf, ino_t inum)
1001{
1002 int i, ret = 0;
1003
1004 spin_lock(&wbuf->lock);
1005 for (i = 0; i < wbuf->next_ino; i++)
1006 if (inum == wbuf->inodes[i]) {
1007 ret = 1;
1008 break;
1009 }
1010 spin_unlock(&wbuf->lock);
1011
1012 return ret;
1013}
1014
1015/**
1016 * ubifs_sync_wbufs_by_inode - synchronize write-buffers for an inode.
1017 * @c: UBIFS file-system description object
1018 * @inode: inode to synchronize
1019 *
1020 * This function synchronizes write-buffers which contain nodes belonging to
1021 * @inode. Returns zero in case of success and a negative error code in case of
1022 * failure.
1023 */
1024int ubifs_sync_wbufs_by_inode(struct ubifs_info *c, struct inode *inode)
1025{
1026 int i, err = 0;
1027
1028 for (i = 0; i < c->jhead_cnt; i++) {
1029 struct ubifs_wbuf *wbuf = &c->jheads[i].wbuf;
1030
1031 if (i == GCHD)
1032 /*
1033 * GC head is special, do not look at it. Even if the
1034 * head contains something related to this inode, it is
1035 * a _copy_ of corresponding on-flash node which sits
1036 * somewhere else.
1037 */
1038 continue;
1039
1040 if (!wbuf_has_ino(wbuf, inode->i_ino))
1041 continue;
1042
1043 mutex_lock_nested(&wbuf->io_mutex, wbuf->jhead);
1044 if (wbuf_has_ino(wbuf, inode->i_ino))
1045 err = ubifs_wbuf_sync_nolock(wbuf);
1046 mutex_unlock(&wbuf->io_mutex);
1047
1048 if (err) {
1049 ubifs_ro_mode(c, err);
1050 return err;
1051 }
1052 }
1053 return 0;
1054}