blob: 6e5c2534f4bc806b965957254a6bea80af646c62 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/**
2 * aops.c - NTFS kernel address space operations and page cache handling.
3 * Part of the Linux-NTFS project.
4 *
Anton Altaparmakov78af34f2006-02-24 10:32:33 +00005 * Copyright (c) 2001-2006 Anton Altaparmakov
Linus Torvalds1da177e2005-04-16 15:20:36 -07006 * Copyright (c) 2002 Richard Russon
7 *
8 * This program/include file is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU General Public License as published
10 * by the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
12 *
13 * This program/include file is distributed in the hope that it will be
14 * useful, but WITHOUT ANY WARRANTY; without even the implied warranty
15 * of 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 License
19 * along with this program (in the main directory of the Linux-NTFS
20 * distribution in the file COPYING); if not, write to the Free Software
21 * Foundation,Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
22 */
23
24#include <linux/errno.h>
Anton Altaparmakov78264bd2006-03-23 15:06:18 +000025#include <linux/fs.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070026#include <linux/mm.h>
27#include <linux/pagemap.h>
28#include <linux/swap.h>
29#include <linux/buffer_head.h>
30#include <linux/writeback.h>
Andrew Mortonb4012a92005-09-10 00:25:47 -070031#include <linux/bit_spinlock.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070032
33#include "aops.h"
34#include "attrib.h"
35#include "debug.h"
36#include "inode.h"
37#include "mft.h"
38#include "runlist.h"
39#include "types.h"
40#include "ntfs.h"
41
42/**
43 * ntfs_end_buffer_async_read - async io completion for reading attributes
44 * @bh: buffer head on which io is completed
45 * @uptodate: whether @bh is now uptodate or not
46 *
47 * Asynchronous I/O completion handler for reading pages belonging to the
48 * attribute address space of an inode. The inodes can either be files or
49 * directories or they can be fake inodes describing some attribute.
50 *
51 * If NInoMstProtected(), perform the post read mst fixups when all IO on the
52 * page has been completed and mark the page uptodate or set the error bit on
53 * the page. To determine the size of the records that need fixing up, we
54 * cheat a little bit by setting the index_block_size in ntfs_inode to the ntfs
55 * record size, and index_block_size_bits, to the log(base 2) of the ntfs
56 * record size.
57 */
58static void ntfs_end_buffer_async_read(struct buffer_head *bh, int uptodate)
59{
Linus Torvalds1da177e2005-04-16 15:20:36 -070060 unsigned long flags;
Anton Altaparmakove6046352005-09-08 22:13:02 +010061 struct buffer_head *first, *tmp;
Linus Torvalds1da177e2005-04-16 15:20:36 -070062 struct page *page;
Anton Altaparmakovf6098cf2005-09-19 09:41:39 +010063 struct inode *vi;
Linus Torvalds1da177e2005-04-16 15:20:36 -070064 ntfs_inode *ni;
65 int page_uptodate = 1;
66
67 page = bh->b_page;
Anton Altaparmakovf6098cf2005-09-19 09:41:39 +010068 vi = page->mapping->host;
69 ni = NTFS_I(vi);
Linus Torvalds1da177e2005-04-16 15:20:36 -070070
71 if (likely(uptodate)) {
Anton Altaparmakovf6098cf2005-09-19 09:41:39 +010072 loff_t i_size;
73 s64 file_ofs, init_size;
Linus Torvalds1da177e2005-04-16 15:20:36 -070074
75 set_buffer_uptodate(bh);
76
77 file_ofs = ((s64)page->index << PAGE_CACHE_SHIFT) +
78 bh_offset(bh);
Anton Altaparmakov07a4e2d2005-01-12 13:08:26 +000079 read_lock_irqsave(&ni->size_lock, flags);
Anton Altaparmakovf6098cf2005-09-19 09:41:39 +010080 init_size = ni->initialized_size;
81 i_size = i_size_read(vi);
Anton Altaparmakov07a4e2d2005-01-12 13:08:26 +000082 read_unlock_irqrestore(&ni->size_lock, flags);
Anton Altaparmakovf6098cf2005-09-19 09:41:39 +010083 if (unlikely(init_size > i_size)) {
84 /* Race with shrinking truncate. */
85 init_size = i_size;
86 }
Linus Torvalds1da177e2005-04-16 15:20:36 -070087 /* Check for the current buffer head overflowing. */
Anton Altaparmakovf6098cf2005-09-19 09:41:39 +010088 if (unlikely(file_ofs + bh->b_size > init_size)) {
Anton Altaparmakovf6098cf2005-09-19 09:41:39 +010089 int ofs;
Linus Torvalds1da177e2005-04-16 15:20:36 -070090
Anton Altaparmakovf6098cf2005-09-19 09:41:39 +010091 ofs = 0;
92 if (file_ofs < init_size)
93 ofs = init_size - file_ofs;
Andrew Mortonfa8609d2007-01-30 14:36:24 -080094 local_irq_save(flags);
Nate Dillere3bf4602007-05-12 10:36:54 -070095 zero_user_page(page, bh_offset(bh) + ofs,
96 bh->b_size - ofs, KM_BIO_SRC_IRQ);
Andrew Mortonfa8609d2007-01-30 14:36:24 -080097 local_irq_restore(flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -070098 }
99 } else {
100 clear_buffer_uptodate(bh);
Anton Altaparmakove6046352005-09-08 22:13:02 +0100101 SetPageError(page);
Anton Altaparmakovf6098cf2005-09-19 09:41:39 +0100102 ntfs_error(ni->vol->sb, "Buffer I/O error, logical block "
103 "0x%llx.", (unsigned long long)bh->b_blocknr);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700104 }
Anton Altaparmakove6046352005-09-08 22:13:02 +0100105 first = page_buffers(page);
106 local_irq_save(flags);
107 bit_spin_lock(BH_Uptodate_Lock, &first->b_state);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700108 clear_buffer_async_read(bh);
109 unlock_buffer(bh);
110 tmp = bh;
111 do {
112 if (!buffer_uptodate(tmp))
113 page_uptodate = 0;
114 if (buffer_async_read(tmp)) {
115 if (likely(buffer_locked(tmp)))
116 goto still_busy;
117 /* Async buffers must be locked. */
118 BUG();
119 }
120 tmp = tmp->b_this_page;
121 } while (tmp != bh);
Anton Altaparmakove6046352005-09-08 22:13:02 +0100122 bit_spin_unlock(BH_Uptodate_Lock, &first->b_state);
123 local_irq_restore(flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700124 /*
125 * If none of the buffers had errors then we can set the page uptodate,
126 * but we first have to perform the post read mst fixups, if the
127 * attribute is mst protected, i.e. if NInoMstProteced(ni) is true.
128 * Note we ignore fixup errors as those are detected when
129 * map_mft_record() is called which gives us per record granularity
130 * rather than per page granularity.
131 */
132 if (!NInoMstProtected(ni)) {
133 if (likely(page_uptodate && !PageError(page)))
134 SetPageUptodate(page);
135 } else {
Anton Altaparmakovf6098cf2005-09-19 09:41:39 +0100136 u8 *kaddr;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700137 unsigned int i, recs;
138 u32 rec_size;
139
140 rec_size = ni->itype.index.block_size;
141 recs = PAGE_CACHE_SIZE / rec_size;
142 /* Should have been verified before we got here... */
143 BUG_ON(!recs);
Andrew Mortonfa8609d2007-01-30 14:36:24 -0800144 local_irq_save(flags);
Anton Altaparmakovf6098cf2005-09-19 09:41:39 +0100145 kaddr = kmap_atomic(page, KM_BIO_SRC_IRQ);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700146 for (i = 0; i < recs; i++)
Anton Altaparmakovf6098cf2005-09-19 09:41:39 +0100147 post_read_mst_fixup((NTFS_RECORD*)(kaddr +
Linus Torvalds1da177e2005-04-16 15:20:36 -0700148 i * rec_size), rec_size);
Anton Altaparmakovf6098cf2005-09-19 09:41:39 +0100149 kunmap_atomic(kaddr, KM_BIO_SRC_IRQ);
Andrew Mortonfa8609d2007-01-30 14:36:24 -0800150 local_irq_restore(flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700151 flush_dcache_page(page);
Anton Altaparmakovb6ad6c52005-02-15 10:08:43 +0000152 if (likely(page_uptodate && !PageError(page)))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700153 SetPageUptodate(page);
154 }
155 unlock_page(page);
156 return;
157still_busy:
Anton Altaparmakove6046352005-09-08 22:13:02 +0100158 bit_spin_unlock(BH_Uptodate_Lock, &first->b_state);
159 local_irq_restore(flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700160 return;
161}
162
163/**
164 * ntfs_read_block - fill a @page of an address space with data
165 * @page: page cache page to fill with data
166 *
167 * Fill the page @page of the address space belonging to the @page->host inode.
168 * We read each buffer asynchronously and when all buffers are read in, our io
169 * completion handler ntfs_end_buffer_read_async(), if required, automatically
170 * applies the mst fixups to the page before finally marking it uptodate and
171 * unlocking it.
172 *
173 * We only enforce allocated_size limit because i_size is checked for in
174 * generic_file_read().
175 *
176 * Return 0 on success and -errno on error.
177 *
178 * Contains an adapted version of fs/buffer.c::block_read_full_page().
179 */
180static int ntfs_read_block(struct page *page)
181{
Anton Altaparmakovf6098cf2005-09-19 09:41:39 +0100182 loff_t i_size;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700183 VCN vcn;
184 LCN lcn;
Anton Altaparmakovf6098cf2005-09-19 09:41:39 +0100185 s64 init_size;
186 struct inode *vi;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700187 ntfs_inode *ni;
188 ntfs_volume *vol;
189 runlist_element *rl;
190 struct buffer_head *bh, *head, *arr[MAX_BUF_PER_PAGE];
191 sector_t iblock, lblock, zblock;
Anton Altaparmakov07a4e2d2005-01-12 13:08:26 +0000192 unsigned long flags;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700193 unsigned int blocksize, vcn_ofs;
194 int i, nr;
195 unsigned char blocksize_bits;
196
Anton Altaparmakovf6098cf2005-09-19 09:41:39 +0100197 vi = page->mapping->host;
198 ni = NTFS_I(vi);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700199 vol = ni->vol;
200
201 /* $MFT/$DATA must have its complete runlist in memory at all times. */
202 BUG_ON(!ni->runlist.rl && !ni->mft_no && !NInoAttr(ni));
203
Anton Altaparmakov78af34f2006-02-24 10:32:33 +0000204 blocksize = vol->sb->s_blocksize;
205 blocksize_bits = vol->sb->s_blocksize_bits;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700206
Anton Altaparmakova01ac532005-09-08 22:08:11 +0100207 if (!page_has_buffers(page)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700208 create_empty_buffers(page, blocksize, 0);
Anton Altaparmakova01ac532005-09-08 22:08:11 +0100209 if (unlikely(!page_has_buffers(page))) {
210 unlock_page(page);
211 return -ENOMEM;
212 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700213 }
Anton Altaparmakova01ac532005-09-08 22:08:11 +0100214 bh = head = page_buffers(page);
215 BUG_ON(!bh);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700216
Anton Altaparmakovf6098cf2005-09-19 09:41:39 +0100217 /*
218 * We may be racing with truncate. To avoid some of the problems we
219 * now take a snapshot of the various sizes and use those for the whole
220 * of the function. In case of an extending truncate it just means we
221 * may leave some buffers unmapped which are now allocated. This is
222 * not a problem since these buffers will just get mapped when a write
223 * occurs. In case of a shrinking truncate, we will detect this later
224 * on due to the runlist being incomplete and if the page is being
225 * fully truncated, truncate will throw it away as soon as we unlock
226 * it so no need to worry what we do with it.
227 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700228 iblock = (s64)page->index << (PAGE_CACHE_SHIFT - blocksize_bits);
Anton Altaparmakov07a4e2d2005-01-12 13:08:26 +0000229 read_lock_irqsave(&ni->size_lock, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700230 lblock = (ni->allocated_size + blocksize - 1) >> blocksize_bits;
Anton Altaparmakovf6098cf2005-09-19 09:41:39 +0100231 init_size = ni->initialized_size;
232 i_size = i_size_read(vi);
Anton Altaparmakov07a4e2d2005-01-12 13:08:26 +0000233 read_unlock_irqrestore(&ni->size_lock, flags);
Anton Altaparmakovf6098cf2005-09-19 09:41:39 +0100234 if (unlikely(init_size > i_size)) {
235 /* Race with shrinking truncate. */
236 init_size = i_size;
237 }
238 zblock = (init_size + blocksize - 1) >> blocksize_bits;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700239
240 /* Loop through all the buffers in the page. */
241 rl = NULL;
242 nr = i = 0;
243 do {
Nate Dillere3bf4602007-05-12 10:36:54 -0700244 int err = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700245
246 if (unlikely(buffer_uptodate(bh)))
247 continue;
248 if (unlikely(buffer_mapped(bh))) {
249 arr[nr++] = bh;
250 continue;
251 }
252 bh->b_bdev = vol->sb->s_bdev;
253 /* Is the block within the allowed limits? */
254 if (iblock < lblock) {
Richard Knutssonc49c3112006-09-30 23:27:12 -0700255 bool is_retry = false;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700256
257 /* Convert iblock into corresponding vcn and offset. */
258 vcn = (VCN)iblock << blocksize_bits >>
259 vol->cluster_size_bits;
260 vcn_ofs = ((VCN)iblock << blocksize_bits) &
261 vol->cluster_size_mask;
262 if (!rl) {
263lock_retry_remap:
264 down_read(&ni->runlist.lock);
265 rl = ni->runlist.rl;
266 }
267 if (likely(rl != NULL)) {
268 /* Seek to element containing target vcn. */
269 while (rl->length && rl[1].vcn <= vcn)
270 rl++;
271 lcn = ntfs_rl_vcn_to_lcn(rl, vcn);
272 } else
273 lcn = LCN_RL_NOT_MAPPED;
274 /* Successful remap. */
275 if (lcn >= 0) {
276 /* Setup buffer head to correct block. */
277 bh->b_blocknr = ((lcn << vol->cluster_size_bits)
278 + vcn_ofs) >> blocksize_bits;
279 set_buffer_mapped(bh);
280 /* Only read initialized data blocks. */
281 if (iblock < zblock) {
282 arr[nr++] = bh;
283 continue;
284 }
285 /* Fully non-initialized data block, zero it. */
286 goto handle_zblock;
287 }
288 /* It is a hole, need to zero it. */
289 if (lcn == LCN_HOLE)
290 goto handle_hole;
291 /* If first try and runlist unmapped, map and retry. */
292 if (!is_retry && lcn == LCN_RL_NOT_MAPPED) {
Richard Knutssonc49c3112006-09-30 23:27:12 -0700293 is_retry = true;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700294 /*
295 * Attempt to map runlist, dropping lock for
296 * the duration.
297 */
298 up_read(&ni->runlist.lock);
299 err = ntfs_map_runlist(ni, vcn);
300 if (likely(!err))
301 goto lock_retry_remap;
302 rl = NULL;
Anton Altaparmakov9f993fe2005-06-25 16:15:36 +0100303 } else if (!rl)
304 up_read(&ni->runlist.lock);
Anton Altaparmakov8273d5d2005-09-08 22:00:33 +0100305 /*
306 * If buffer is outside the runlist, treat it as a
307 * hole. This can happen due to concurrent truncate
308 * for example.
309 */
310 if (err == -ENOENT || lcn == LCN_ENOENT) {
311 err = 0;
312 goto handle_hole;
313 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700314 /* Hard error, zero out region. */
Anton Altaparmakov8273d5d2005-09-08 22:00:33 +0100315 if (!err)
316 err = -EIO;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700317 bh->b_blocknr = -1;
318 SetPageError(page);
319 ntfs_error(vol->sb, "Failed to read from inode 0x%lx, "
320 "attribute type 0x%x, vcn 0x%llx, "
321 "offset 0x%x because its location on "
322 "disk could not be determined%s "
Anton Altaparmakov8273d5d2005-09-08 22:00:33 +0100323 "(error code %i).", ni->mft_no,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700324 ni->type, (unsigned long long)vcn,
325 vcn_ofs, is_retry ? " even after "
Anton Altaparmakov8273d5d2005-09-08 22:00:33 +0100326 "retrying" : "", err);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700327 }
328 /*
329 * Either iblock was outside lblock limits or
330 * ntfs_rl_vcn_to_lcn() returned error. Just zero that portion
331 * of the page and set the buffer uptodate.
332 */
333handle_hole:
334 bh->b_blocknr = -1UL;
335 clear_buffer_mapped(bh);
336handle_zblock:
Nate Dillere3bf4602007-05-12 10:36:54 -0700337 zero_user_page(page, i * blocksize, blocksize, KM_USER0);
Anton Altaparmakov8273d5d2005-09-08 22:00:33 +0100338 if (likely(!err))
339 set_buffer_uptodate(bh);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700340 } while (i++, iblock++, (bh = bh->b_this_page) != head);
341
342 /* Release the lock if we took it. */
343 if (rl)
344 up_read(&ni->runlist.lock);
345
346 /* Check we have at least one buffer ready for i/o. */
347 if (nr) {
348 struct buffer_head *tbh;
349
350 /* Lock the buffers. */
351 for (i = 0; i < nr; i++) {
352 tbh = arr[i];
353 lock_buffer(tbh);
354 tbh->b_end_io = ntfs_end_buffer_async_read;
355 set_buffer_async_read(tbh);
356 }
357 /* Finally, start i/o on the buffers. */
358 for (i = 0; i < nr; i++) {
359 tbh = arr[i];
360 if (likely(!buffer_uptodate(tbh)))
361 submit_bh(READ, tbh);
362 else
363 ntfs_end_buffer_async_read(tbh, 1);
364 }
365 return 0;
366 }
367 /* No i/o was scheduled on any of the buffers. */
368 if (likely(!PageError(page)))
369 SetPageUptodate(page);
370 else /* Signal synchronous i/o error. */
371 nr = -EIO;
372 unlock_page(page);
373 return nr;
374}
375
376/**
377 * ntfs_readpage - fill a @page of a @file with data from the device
378 * @file: open file to which the page @page belongs or NULL
379 * @page: page cache page to fill with data
380 *
381 * For non-resident attributes, ntfs_readpage() fills the @page of the open
382 * file @file by calling the ntfs version of the generic block_read_full_page()
383 * function, ntfs_read_block(), which in turn creates and reads in the buffers
384 * associated with the page asynchronously.
385 *
386 * For resident attributes, OTOH, ntfs_readpage() fills @page by copying the
387 * data from the mft record (which at this stage is most likely in memory) and
388 * fills the remainder with zeroes. Thus, in this case, I/O is synchronous, as
389 * even if the mft record is not cached at this point in time, we need to wait
390 * for it to be read in before we can do the copy.
391 *
392 * Return 0 on success and -errno on error.
393 */
394static int ntfs_readpage(struct file *file, struct page *page)
395{
Anton Altaparmakovf6098cf2005-09-19 09:41:39 +0100396 loff_t i_size;
397 struct inode *vi;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700398 ntfs_inode *ni, *base_ni;
399 u8 *kaddr;
400 ntfs_attr_search_ctx *ctx;
401 MFT_RECORD *mrec;
Anton Altaparmakovb6ad6c52005-02-15 10:08:43 +0000402 unsigned long flags;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700403 u32 attr_len;
404 int err = 0;
405
Anton Altaparmakov905685f2005-03-10 11:06:19 +0000406retry_readpage:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700407 BUG_ON(!PageLocked(page));
408 /*
409 * This can potentially happen because we clear PageUptodate() during
410 * ntfs_writepage() of MstProtected() attributes.
411 */
412 if (PageUptodate(page)) {
413 unlock_page(page);
414 return 0;
415 }
Anton Altaparmakovf6098cf2005-09-19 09:41:39 +0100416 vi = page->mapping->host;
417 ni = NTFS_I(vi);
Anton Altaparmakov311120e2005-09-08 22:04:20 +0100418 /*
419 * Only $DATA attributes can be encrypted and only unnamed $DATA
420 * attributes can be compressed. Index root can have the flags set but
421 * this means to create compressed/encrypted files, not that the
Anton Altaparmakov4e64c882005-09-19 09:38:41 +0100422 * attribute is compressed/encrypted. Note we need to check for
423 * AT_INDEX_ALLOCATION since this is the type of both directory and
424 * index inodes.
Anton Altaparmakov311120e2005-09-08 22:04:20 +0100425 */
Anton Altaparmakov4e64c882005-09-19 09:38:41 +0100426 if (ni->type != AT_INDEX_ALLOCATION) {
Anton Altaparmakov311120e2005-09-08 22:04:20 +0100427 /* If attribute is encrypted, deny access, just like NT4. */
428 if (NInoEncrypted(ni)) {
429 BUG_ON(ni->type != AT_DATA);
430 err = -EACCES;
431 goto err_out;
432 }
433 /* Compressed data streams are handled in compress.c. */
434 if (NInoNonResident(ni) && NInoCompressed(ni)) {
435 BUG_ON(ni->type != AT_DATA);
436 BUG_ON(ni->name_len);
437 return ntfs_read_compressed_block(page);
438 }
439 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700440 /* NInoNonResident() == NInoIndexAllocPresent() */
441 if (NInoNonResident(ni)) {
Anton Altaparmakov311120e2005-09-08 22:04:20 +0100442 /* Normal, non-resident data stream. */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700443 return ntfs_read_block(page);
444 }
445 /*
446 * Attribute is resident, implying it is not compressed or encrypted.
447 * This also means the attribute is smaller than an mft record and
448 * hence smaller than a page, so can simply zero out any pages with
Anton Altaparmakov311120e2005-09-08 22:04:20 +0100449 * index above 0. Note the attribute can actually be marked compressed
450 * but if it is resident the actual data is not compressed so we are
451 * ok to ignore the compressed flag here.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700452 */
Anton Altaparmakovb6ad6c52005-02-15 10:08:43 +0000453 if (unlikely(page->index > 0)) {
Nate Dillere3bf4602007-05-12 10:36:54 -0700454 zero_user_page(page, 0, PAGE_CACHE_SIZE, KM_USER0);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700455 goto done;
456 }
457 if (!NInoAttr(ni))
458 base_ni = ni;
459 else
460 base_ni = ni->ext.base_ntfs_ino;
461 /* Map, pin, and lock the mft record. */
462 mrec = map_mft_record(base_ni);
463 if (IS_ERR(mrec)) {
464 err = PTR_ERR(mrec);
465 goto err_out;
466 }
Anton Altaparmakov905685f2005-03-10 11:06:19 +0000467 /*
468 * If a parallel write made the attribute non-resident, drop the mft
469 * record and retry the readpage.
470 */
471 if (unlikely(NInoNonResident(ni))) {
472 unmap_mft_record(base_ni);
473 goto retry_readpage;
474 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700475 ctx = ntfs_attr_get_search_ctx(base_ni, mrec);
476 if (unlikely(!ctx)) {
477 err = -ENOMEM;
478 goto unm_err_out;
479 }
480 err = ntfs_attr_lookup(ni->type, ni->name, ni->name_len,
481 CASE_SENSITIVE, 0, NULL, 0, ctx);
482 if (unlikely(err))
483 goto put_unm_err_out;
484 attr_len = le32_to_cpu(ctx->attr->data.resident.value_length);
Anton Altaparmakovb6ad6c52005-02-15 10:08:43 +0000485 read_lock_irqsave(&ni->size_lock, flags);
486 if (unlikely(attr_len > ni->initialized_size))
487 attr_len = ni->initialized_size;
Anton Altaparmakovf6098cf2005-09-19 09:41:39 +0100488 i_size = i_size_read(vi);
Anton Altaparmakovb6ad6c52005-02-15 10:08:43 +0000489 read_unlock_irqrestore(&ni->size_lock, flags);
Anton Altaparmakovf6098cf2005-09-19 09:41:39 +0100490 if (unlikely(attr_len > i_size)) {
491 /* Race with shrinking truncate. */
492 attr_len = i_size;
493 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700494 kaddr = kmap_atomic(page, KM_USER0);
495 /* Copy the data to the page. */
496 memcpy(kaddr, (u8*)ctx->attr +
497 le16_to_cpu(ctx->attr->data.resident.value_offset),
498 attr_len);
499 /* Zero the remainder of the page. */
500 memset(kaddr + attr_len, 0, PAGE_CACHE_SIZE - attr_len);
501 flush_dcache_page(page);
502 kunmap_atomic(kaddr, KM_USER0);
503put_unm_err_out:
504 ntfs_attr_put_search_ctx(ctx);
505unm_err_out:
506 unmap_mft_record(base_ni);
507done:
508 SetPageUptodate(page);
509err_out:
510 unlock_page(page);
511 return err;
512}
513
514#ifdef NTFS_RW
515
516/**
517 * ntfs_write_block - write a @page to the backing store
518 * @page: page cache page to write out
519 * @wbc: writeback control structure
520 *
521 * This function is for writing pages belonging to non-resident, non-mst
522 * protected attributes to their backing store.
523 *
524 * For a page with buffers, map and write the dirty buffers asynchronously
525 * under page writeback. For a page without buffers, create buffers for the
526 * page, then proceed as above.
527 *
528 * If a page doesn't have buffers the page dirty state is definitive. If a page
529 * does have buffers, the page dirty state is just a hint, and the buffer dirty
530 * state is definitive. (A hint which has rules: dirty buffers against a clean
531 * page is illegal. Other combinations are legal and need to be handled. In
532 * particular a dirty page containing clean buffers for example.)
533 *
534 * Return 0 on success and -errno on error.
535 *
536 * Based on ntfs_read_block() and __block_write_full_page().
537 */
538static int ntfs_write_block(struct page *page, struct writeback_control *wbc)
539{
540 VCN vcn;
541 LCN lcn;
Anton Altaparmakov07a4e2d2005-01-12 13:08:26 +0000542 s64 initialized_size;
543 loff_t i_size;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700544 sector_t block, dblock, iblock;
545 struct inode *vi;
546 ntfs_inode *ni;
547 ntfs_volume *vol;
548 runlist_element *rl;
549 struct buffer_head *bh, *head;
Anton Altaparmakov07a4e2d2005-01-12 13:08:26 +0000550 unsigned long flags;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700551 unsigned int blocksize, vcn_ofs;
552 int err;
Richard Knutssonc49c3112006-09-30 23:27:12 -0700553 bool need_end_writeback;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700554 unsigned char blocksize_bits;
555
556 vi = page->mapping->host;
557 ni = NTFS_I(vi);
558 vol = ni->vol;
559
560 ntfs_debug("Entering for inode 0x%lx, attribute type 0x%x, page index "
561 "0x%lx.", ni->mft_no, ni->type, page->index);
562
563 BUG_ON(!NInoNonResident(ni));
564 BUG_ON(NInoMstProtected(ni));
Anton Altaparmakov78af34f2006-02-24 10:32:33 +0000565 blocksize = vol->sb->s_blocksize;
566 blocksize_bits = vol->sb->s_blocksize_bits;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700567 if (!page_has_buffers(page)) {
568 BUG_ON(!PageUptodate(page));
569 create_empty_buffers(page, blocksize,
570 (1 << BH_Uptodate) | (1 << BH_Dirty));
Anton Altaparmakova01ac532005-09-08 22:08:11 +0100571 if (unlikely(!page_has_buffers(page))) {
572 ntfs_warning(vol->sb, "Error allocating page "
573 "buffers. Redirtying page so we try "
574 "again later.");
575 /*
576 * Put the page back on mapping->dirty_pages, but leave
577 * its buffers' dirty state as-is.
578 */
579 redirty_page_for_writepage(wbc, page);
580 unlock_page(page);
581 return 0;
582 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700583 }
584 bh = head = page_buffers(page);
Anton Altaparmakova01ac532005-09-08 22:08:11 +0100585 BUG_ON(!bh);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700586
587 /* NOTE: Different naming scheme to ntfs_read_block()! */
588
589 /* The first block in the page. */
590 block = (s64)page->index << (PAGE_CACHE_SHIFT - blocksize_bits);
591
Anton Altaparmakov07a4e2d2005-01-12 13:08:26 +0000592 read_lock_irqsave(&ni->size_lock, flags);
593 i_size = i_size_read(vi);
594 initialized_size = ni->initialized_size;
595 read_unlock_irqrestore(&ni->size_lock, flags);
596
Linus Torvalds1da177e2005-04-16 15:20:36 -0700597 /* The first out of bounds block for the data size. */
Anton Altaparmakov07a4e2d2005-01-12 13:08:26 +0000598 dblock = (i_size + blocksize - 1) >> blocksize_bits;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700599
600 /* The last (fully or partially) initialized block. */
Anton Altaparmakov07a4e2d2005-01-12 13:08:26 +0000601 iblock = initialized_size >> blocksize_bits;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700602
603 /*
604 * Be very careful. We have no exclusion from __set_page_dirty_buffers
605 * here, and the (potentially unmapped) buffers may become dirty at
606 * any time. If a buffer becomes dirty here after we've inspected it
607 * then we just miss that fact, and the page stays dirty.
608 *
609 * Buffers outside i_size may be dirtied by __set_page_dirty_buffers;
610 * handle that here by just cleaning them.
611 */
612
613 /*
614 * Loop through all the buffers in the page, mapping all the dirty
615 * buffers to disk addresses and handling any aliases from the
616 * underlying block device's mapping.
617 */
618 rl = NULL;
619 err = 0;
620 do {
Richard Knutssonc49c3112006-09-30 23:27:12 -0700621 bool is_retry = false;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700622
623 if (unlikely(block >= dblock)) {
624 /*
625 * Mapped buffers outside i_size will occur, because
626 * this page can be outside i_size when there is a
627 * truncate in progress. The contents of such buffers
628 * were zeroed by ntfs_writepage().
629 *
630 * FIXME: What about the small race window where
631 * ntfs_writepage() has not done any clearing because
632 * the page was within i_size but before we get here,
633 * vmtruncate() modifies i_size?
634 */
635 clear_buffer_dirty(bh);
636 set_buffer_uptodate(bh);
637 continue;
638 }
639
640 /* Clean buffers are not written out, so no need to map them. */
641 if (!buffer_dirty(bh))
642 continue;
643
644 /* Make sure we have enough initialized size. */
645 if (unlikely((block >= iblock) &&
Anton Altaparmakov07a4e2d2005-01-12 13:08:26 +0000646 (initialized_size < i_size))) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700647 /*
648 * If this page is fully outside initialized size, zero
649 * out all pages between the current initialized size
650 * and the current page. Just use ntfs_readpage() to do
651 * the zeroing transparently.
652 */
653 if (block > iblock) {
654 // TODO:
655 // For each page do:
656 // - read_cache_page()
657 // Again for each page do:
658 // - wait_on_page_locked()
659 // - Check (PageUptodate(page) &&
660 // !PageError(page))
661 // Update initialized size in the attribute and
662 // in the inode.
663 // Again, for each page do:
664 // __set_page_dirty_buffers();
665 // page_cache_release()
666 // We don't need to wait on the writes.
667 // Update iblock.
668 }
669 /*
670 * The current page straddles initialized size. Zero
671 * all non-uptodate buffers and set them uptodate (and
672 * dirty?). Note, there aren't any non-uptodate buffers
673 * if the page is uptodate.
674 * FIXME: For an uptodate page, the buffers may need to
675 * be written out because they were not initialized on
676 * disk before.
677 */
678 if (!PageUptodate(page)) {
679 // TODO:
680 // Zero any non-uptodate buffers up to i_size.
681 // Set them uptodate and dirty.
682 }
683 // TODO:
684 // Update initialized size in the attribute and in the
685 // inode (up to i_size).
686 // Update iblock.
687 // FIXME: This is inefficient. Try to batch the two
688 // size changes to happen in one go.
689 ntfs_error(vol->sb, "Writing beyond initialized size "
690 "is not supported yet. Sorry.");
691 err = -EOPNOTSUPP;
692 break;
693 // Do NOT set_buffer_new() BUT DO clear buffer range
694 // outside write request range.
695 // set_buffer_uptodate() on complete buffers as well as
696 // set_buffer_dirty().
697 }
698
699 /* No need to map buffers that are already mapped. */
700 if (buffer_mapped(bh))
701 continue;
702
703 /* Unmapped, dirty buffer. Need to map it. */
704 bh->b_bdev = vol->sb->s_bdev;
705
706 /* Convert block into corresponding vcn and offset. */
707 vcn = (VCN)block << blocksize_bits;
708 vcn_ofs = vcn & vol->cluster_size_mask;
709 vcn >>= vol->cluster_size_bits;
710 if (!rl) {
711lock_retry_remap:
712 down_read(&ni->runlist.lock);
713 rl = ni->runlist.rl;
714 }
715 if (likely(rl != NULL)) {
716 /* Seek to element containing target vcn. */
717 while (rl->length && rl[1].vcn <= vcn)
718 rl++;
719 lcn = ntfs_rl_vcn_to_lcn(rl, vcn);
720 } else
721 lcn = LCN_RL_NOT_MAPPED;
722 /* Successful remap. */
723 if (lcn >= 0) {
724 /* Setup buffer head to point to correct block. */
725 bh->b_blocknr = ((lcn << vol->cluster_size_bits) +
726 vcn_ofs) >> blocksize_bits;
727 set_buffer_mapped(bh);
728 continue;
729 }
730 /* It is a hole, need to instantiate it. */
731 if (lcn == LCN_HOLE) {
Anton Altaparmakov8dcdeba2005-09-08 21:25:48 +0100732 u8 *kaddr;
733 unsigned long *bpos, *bend;
734
735 /* Check if the buffer is zero. */
736 kaddr = kmap_atomic(page, KM_USER0);
737 bpos = (unsigned long *)(kaddr + bh_offset(bh));
738 bend = (unsigned long *)((u8*)bpos + blocksize);
739 do {
740 if (unlikely(*bpos))
741 break;
742 } while (likely(++bpos < bend));
743 kunmap_atomic(kaddr, KM_USER0);
744 if (bpos == bend) {
745 /*
746 * Buffer is zero and sparse, no need to write
747 * it.
748 */
749 bh->b_blocknr = -1;
750 clear_buffer_dirty(bh);
751 continue;
752 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700753 // TODO: Instantiate the hole.
754 // clear_buffer_new(bh);
755 // unmap_underlying_metadata(bh->b_bdev, bh->b_blocknr);
756 ntfs_error(vol->sb, "Writing into sparse regions is "
757 "not supported yet. Sorry.");
758 err = -EOPNOTSUPP;
759 break;
760 }
761 /* If first try and runlist unmapped, map and retry. */
762 if (!is_retry && lcn == LCN_RL_NOT_MAPPED) {
Richard Knutssonc49c3112006-09-30 23:27:12 -0700763 is_retry = true;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700764 /*
765 * Attempt to map runlist, dropping lock for
766 * the duration.
767 */
768 up_read(&ni->runlist.lock);
769 err = ntfs_map_runlist(ni, vcn);
770 if (likely(!err))
771 goto lock_retry_remap;
772 rl = NULL;
Anton Altaparmakov9f993fe2005-06-25 16:15:36 +0100773 } else if (!rl)
774 up_read(&ni->runlist.lock);
Anton Altaparmakov8273d5d2005-09-08 22:00:33 +0100775 /*
776 * If buffer is outside the runlist, truncate has cut it out
777 * of the runlist. Just clean and clear the buffer and set it
778 * uptodate so it can get discarded by the VM.
779 */
780 if (err == -ENOENT || lcn == LCN_ENOENT) {
Anton Altaparmakov8273d5d2005-09-08 22:00:33 +0100781 bh->b_blocknr = -1;
782 clear_buffer_dirty(bh);
Nate Dillere3bf4602007-05-12 10:36:54 -0700783 zero_user_page(page, bh_offset(bh), blocksize,
784 KM_USER0);
Anton Altaparmakov8273d5d2005-09-08 22:00:33 +0100785 set_buffer_uptodate(bh);
786 err = 0;
787 continue;
788 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700789 /* Failed to map the buffer, even after retrying. */
Anton Altaparmakov8273d5d2005-09-08 22:00:33 +0100790 if (!err)
791 err = -EIO;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700792 bh->b_blocknr = -1;
793 ntfs_error(vol->sb, "Failed to write to inode 0x%lx, "
794 "attribute type 0x%x, vcn 0x%llx, offset 0x%x "
795 "because its location on disk could not be "
Anton Altaparmakov8273d5d2005-09-08 22:00:33 +0100796 "determined%s (error code %i).", ni->mft_no,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700797 ni->type, (unsigned long long)vcn,
798 vcn_ofs, is_retry ? " even after "
Anton Altaparmakov8273d5d2005-09-08 22:00:33 +0100799 "retrying" : "", err);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700800 break;
801 } while (block++, (bh = bh->b_this_page) != head);
802
803 /* Release the lock if we took it. */
804 if (rl)
805 up_read(&ni->runlist.lock);
806
807 /* For the error case, need to reset bh to the beginning. */
808 bh = head;
809
Anton Altaparmakov54b02eb2005-09-08 21:43:47 +0100810 /* Just an optimization, so ->readpage() is not called later. */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700811 if (unlikely(!PageUptodate(page))) {
812 int uptodate = 1;
813 do {
814 if (!buffer_uptodate(bh)) {
815 uptodate = 0;
816 bh = head;
817 break;
818 }
819 } while ((bh = bh->b_this_page) != head);
820 if (uptodate)
821 SetPageUptodate(page);
822 }
823
824 /* Setup all mapped, dirty buffers for async write i/o. */
825 do {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700826 if (buffer_mapped(bh) && buffer_dirty(bh)) {
827 lock_buffer(bh);
828 if (test_clear_buffer_dirty(bh)) {
829 BUG_ON(!buffer_uptodate(bh));
830 mark_buffer_async_write(bh);
831 } else
832 unlock_buffer(bh);
833 } else if (unlikely(err)) {
834 /*
835 * For the error case. The buffer may have been set
836 * dirty during attachment to a dirty page.
837 */
838 if (err != -ENOMEM)
839 clear_buffer_dirty(bh);
840 }
841 } while ((bh = bh->b_this_page) != head);
842
843 if (unlikely(err)) {
844 // TODO: Remove the -EOPNOTSUPP check later on...
845 if (unlikely(err == -EOPNOTSUPP))
846 err = 0;
847 else if (err == -ENOMEM) {
848 ntfs_warning(vol->sb, "Error allocating memory. "
849 "Redirtying page so we try again "
850 "later.");
851 /*
852 * Put the page back on mapping->dirty_pages, but
853 * leave its buffer's dirty state as-is.
854 */
855 redirty_page_for_writepage(wbc, page);
856 err = 0;
857 } else
858 SetPageError(page);
859 }
860
861 BUG_ON(PageWriteback(page));
862 set_page_writeback(page); /* Keeps try_to_free_buffers() away. */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700863
Anton Altaparmakov54b02eb2005-09-08 21:43:47 +0100864 /* Submit the prepared buffers for i/o. */
Richard Knutssonc49c3112006-09-30 23:27:12 -0700865 need_end_writeback = true;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700866 do {
867 struct buffer_head *next = bh->b_this_page;
868 if (buffer_async_write(bh)) {
869 submit_bh(WRITE, bh);
Richard Knutssonc49c3112006-09-30 23:27:12 -0700870 need_end_writeback = false;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700871 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700872 bh = next;
873 } while (bh != head);
Anton Altaparmakov54b02eb2005-09-08 21:43:47 +0100874 unlock_page(page);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700875
876 /* If no i/o was started, need to end_page_writeback(). */
877 if (unlikely(need_end_writeback))
878 end_page_writeback(page);
879
880 ntfs_debug("Done.");
881 return err;
882}
883
884/**
885 * ntfs_write_mst_block - write a @page to the backing store
886 * @page: page cache page to write out
887 * @wbc: writeback control structure
888 *
889 * This function is for writing pages belonging to non-resident, mst protected
890 * attributes to their backing store. The only supported attributes are index
891 * allocation and $MFT/$DATA. Both directory inodes and index inodes are
892 * supported for the index allocation case.
893 *
894 * The page must remain locked for the duration of the write because we apply
895 * the mst fixups, write, and then undo the fixups, so if we were to unlock the
896 * page before undoing the fixups, any other user of the page will see the
897 * page contents as corrupt.
898 *
899 * We clear the page uptodate flag for the duration of the function to ensure
900 * exclusion for the $MFT/$DATA case against someone mapping an mft record we
901 * are about to apply the mst fixups to.
902 *
903 * Return 0 on success and -errno on error.
904 *
905 * Based on ntfs_write_block(), ntfs_mft_writepage(), and
906 * write_mft_record_nolock().
907 */
908static int ntfs_write_mst_block(struct page *page,
909 struct writeback_control *wbc)
910{
911 sector_t block, dblock, rec_block;
912 struct inode *vi = page->mapping->host;
913 ntfs_inode *ni = NTFS_I(vi);
914 ntfs_volume *vol = ni->vol;
915 u8 *kaddr;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700916 unsigned int rec_size = ni->itype.index.block_size;
917 ntfs_inode *locked_nis[PAGE_CACHE_SIZE / rec_size];
918 struct buffer_head *bh, *head, *tbh, *rec_start_bh;
Anton Altaparmakovd53ee322005-04-06 16:11:20 +0100919 struct buffer_head *bhs[MAX_BUF_PER_PAGE];
Linus Torvalds1da177e2005-04-16 15:20:36 -0700920 runlist_element *rl;
Anton Altaparmakovd53ee322005-04-06 16:11:20 +0100921 int i, nr_locked_nis, nr_recs, nr_bhs, max_bhs, bhs_per_rec, err, err2;
922 unsigned bh_size, rec_size_bits;
Richard Knutssonc49c3112006-09-30 23:27:12 -0700923 bool sync, is_mft, page_is_dirty, rec_is_dirty;
Anton Altaparmakovd53ee322005-04-06 16:11:20 +0100924 unsigned char bh_size_bits;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700925
926 ntfs_debug("Entering for inode 0x%lx, attribute type 0x%x, page index "
927 "0x%lx.", vi->i_ino, ni->type, page->index);
928 BUG_ON(!NInoNonResident(ni));
929 BUG_ON(!NInoMstProtected(ni));
930 is_mft = (S_ISREG(vi->i_mode) && !vi->i_ino);
931 /*
932 * NOTE: ntfs_write_mst_block() would be called for $MFTMirr if a page
933 * in its page cache were to be marked dirty. However this should
934 * never happen with the current driver and considering we do not
935 * handle this case here we do want to BUG(), at least for now.
936 */
937 BUG_ON(!(is_mft || S_ISDIR(vi->i_mode) ||
938 (NInoAttr(ni) && ni->type == AT_INDEX_ALLOCATION)));
Anton Altaparmakov78af34f2006-02-24 10:32:33 +0000939 bh_size = vol->sb->s_blocksize;
940 bh_size_bits = vol->sb->s_blocksize_bits;
Anton Altaparmakovd53ee322005-04-06 16:11:20 +0100941 max_bhs = PAGE_CACHE_SIZE / bh_size;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700942 BUG_ON(!max_bhs);
Anton Altaparmakovd53ee322005-04-06 16:11:20 +0100943 BUG_ON(max_bhs > MAX_BUF_PER_PAGE);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700944
945 /* Were we called for sync purposes? */
946 sync = (wbc->sync_mode == WB_SYNC_ALL);
947
948 /* Make sure we have mapped buffers. */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700949 bh = head = page_buffers(page);
950 BUG_ON(!bh);
951
952 rec_size_bits = ni->itype.index.block_size_bits;
953 BUG_ON(!(PAGE_CACHE_SIZE >> rec_size_bits));
954 bhs_per_rec = rec_size >> bh_size_bits;
955 BUG_ON(!bhs_per_rec);
956
957 /* The first block in the page. */
958 rec_block = block = (sector_t)page->index <<
959 (PAGE_CACHE_SHIFT - bh_size_bits);
960
961 /* The first out of bounds block for the data size. */
Anton Altaparmakov07a4e2d2005-01-12 13:08:26 +0000962 dblock = (i_size_read(vi) + bh_size - 1) >> bh_size_bits;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700963
964 rl = NULL;
965 err = err2 = nr_bhs = nr_recs = nr_locked_nis = 0;
Richard Knutssonc49c3112006-09-30 23:27:12 -0700966 page_is_dirty = rec_is_dirty = false;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700967 rec_start_bh = NULL;
968 do {
Richard Knutssonc49c3112006-09-30 23:27:12 -0700969 bool is_retry = false;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700970
971 if (likely(block < rec_block)) {
972 if (unlikely(block >= dblock)) {
973 clear_buffer_dirty(bh);
Anton Altaparmakov946929d2005-01-13 15:26:29 +0000974 set_buffer_uptodate(bh);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700975 continue;
976 }
977 /*
978 * This block is not the first one in the record. We
979 * ignore the buffer's dirty state because we could
980 * have raced with a parallel mark_ntfs_record_dirty().
981 */
982 if (!rec_is_dirty)
983 continue;
984 if (unlikely(err2)) {
985 if (err2 != -ENOMEM)
986 clear_buffer_dirty(bh);
987 continue;
988 }
989 } else /* if (block == rec_block) */ {
990 BUG_ON(block > rec_block);
991 /* This block is the first one in the record. */
992 rec_block += bhs_per_rec;
993 err2 = 0;
994 if (unlikely(block >= dblock)) {
995 clear_buffer_dirty(bh);
996 continue;
997 }
998 if (!buffer_dirty(bh)) {
999 /* Clean records are not written out. */
Richard Knutssonc49c3112006-09-30 23:27:12 -07001000 rec_is_dirty = false;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001001 continue;
1002 }
Richard Knutssonc49c3112006-09-30 23:27:12 -07001003 rec_is_dirty = true;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001004 rec_start_bh = bh;
1005 }
1006 /* Need to map the buffer if it is not mapped already. */
1007 if (unlikely(!buffer_mapped(bh))) {
1008 VCN vcn;
1009 LCN lcn;
1010 unsigned int vcn_ofs;
1011
Anton Altaparmakov481d0372005-08-16 19:42:56 +01001012 bh->b_bdev = vol->sb->s_bdev;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001013 /* Obtain the vcn and offset of the current block. */
1014 vcn = (VCN)block << bh_size_bits;
1015 vcn_ofs = vcn & vol->cluster_size_mask;
1016 vcn >>= vol->cluster_size_bits;
1017 if (!rl) {
1018lock_retry_remap:
1019 down_read(&ni->runlist.lock);
1020 rl = ni->runlist.rl;
1021 }
1022 if (likely(rl != NULL)) {
1023 /* Seek to element containing target vcn. */
1024 while (rl->length && rl[1].vcn <= vcn)
1025 rl++;
1026 lcn = ntfs_rl_vcn_to_lcn(rl, vcn);
1027 } else
1028 lcn = LCN_RL_NOT_MAPPED;
1029 /* Successful remap. */
1030 if (likely(lcn >= 0)) {
1031 /* Setup buffer head to correct block. */
1032 bh->b_blocknr = ((lcn <<
1033 vol->cluster_size_bits) +
1034 vcn_ofs) >> bh_size_bits;
1035 set_buffer_mapped(bh);
1036 } else {
1037 /*
1038 * Remap failed. Retry to map the runlist once
1039 * unless we are working on $MFT which always
1040 * has the whole of its runlist in memory.
1041 */
1042 if (!is_mft && !is_retry &&
1043 lcn == LCN_RL_NOT_MAPPED) {
Richard Knutssonc49c3112006-09-30 23:27:12 -07001044 is_retry = true;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001045 /*
1046 * Attempt to map runlist, dropping
1047 * lock for the duration.
1048 */
1049 up_read(&ni->runlist.lock);
1050 err2 = ntfs_map_runlist(ni, vcn);
1051 if (likely(!err2))
1052 goto lock_retry_remap;
1053 if (err2 == -ENOMEM)
Richard Knutssonc49c3112006-09-30 23:27:12 -07001054 page_is_dirty = true;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001055 lcn = err2;
Anton Altaparmakov9f993fe2005-06-25 16:15:36 +01001056 } else {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001057 err2 = -EIO;
Anton Altaparmakov9f993fe2005-06-25 16:15:36 +01001058 if (!rl)
1059 up_read(&ni->runlist.lock);
1060 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001061 /* Hard error. Abort writing this record. */
1062 if (!err || err == -ENOMEM)
1063 err = err2;
1064 bh->b_blocknr = -1;
1065 ntfs_error(vol->sb, "Cannot write ntfs record "
1066 "0x%llx (inode 0x%lx, "
1067 "attribute type 0x%x) because "
1068 "its location on disk could "
1069 "not be determined (error "
Randy Dunlap89075472005-03-03 11:19:53 +00001070 "code %lli).",
1071 (long long)block <<
Linus Torvalds1da177e2005-04-16 15:20:36 -07001072 bh_size_bits >>
1073 vol->mft_record_size_bits,
1074 ni->mft_no, ni->type,
1075 (long long)lcn);
1076 /*
1077 * If this is not the first buffer, remove the
1078 * buffers in this record from the list of
1079 * buffers to write and clear their dirty bit
1080 * if not error -ENOMEM.
1081 */
1082 if (rec_start_bh != bh) {
1083 while (bhs[--nr_bhs] != rec_start_bh)
1084 ;
1085 if (err2 != -ENOMEM) {
1086 do {
1087 clear_buffer_dirty(
1088 rec_start_bh);
1089 } while ((rec_start_bh =
1090 rec_start_bh->
1091 b_this_page) !=
1092 bh);
1093 }
1094 }
1095 continue;
1096 }
1097 }
1098 BUG_ON(!buffer_uptodate(bh));
1099 BUG_ON(nr_bhs >= max_bhs);
1100 bhs[nr_bhs++] = bh;
1101 } while (block++, (bh = bh->b_this_page) != head);
1102 if (unlikely(rl))
1103 up_read(&ni->runlist.lock);
1104 /* If there were no dirty buffers, we are done. */
1105 if (!nr_bhs)
1106 goto done;
1107 /* Map the page so we can access its contents. */
1108 kaddr = kmap(page);
1109 /* Clear the page uptodate flag whilst the mst fixups are applied. */
1110 BUG_ON(!PageUptodate(page));
1111 ClearPageUptodate(page);
1112 for (i = 0; i < nr_bhs; i++) {
1113 unsigned int ofs;
1114
1115 /* Skip buffers which are not at the beginning of records. */
1116 if (i % bhs_per_rec)
1117 continue;
1118 tbh = bhs[i];
1119 ofs = bh_offset(tbh);
1120 if (is_mft) {
1121 ntfs_inode *tni;
1122 unsigned long mft_no;
1123
1124 /* Get the mft record number. */
1125 mft_no = (((s64)page->index << PAGE_CACHE_SHIFT) + ofs)
1126 >> rec_size_bits;
1127 /* Check whether to write this mft record. */
1128 tni = NULL;
1129 if (!ntfs_may_write_mft_record(vol, mft_no,
1130 (MFT_RECORD*)(kaddr + ofs), &tni)) {
1131 /*
1132 * The record should not be written. This
1133 * means we need to redirty the page before
1134 * returning.
1135 */
Richard Knutssonc49c3112006-09-30 23:27:12 -07001136 page_is_dirty = true;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001137 /*
1138 * Remove the buffers in this mft record from
1139 * the list of buffers to write.
1140 */
1141 do {
1142 bhs[i] = NULL;
1143 } while (++i % bhs_per_rec);
1144 continue;
1145 }
1146 /*
1147 * The record should be written. If a locked ntfs
1148 * inode was returned, add it to the array of locked
1149 * ntfs inodes.
1150 */
1151 if (tni)
1152 locked_nis[nr_locked_nis++] = tni;
1153 }
1154 /* Apply the mst protection fixups. */
1155 err2 = pre_write_mst_fixup((NTFS_RECORD*)(kaddr + ofs),
1156 rec_size);
1157 if (unlikely(err2)) {
1158 if (!err || err == -ENOMEM)
1159 err = -EIO;
1160 ntfs_error(vol->sb, "Failed to apply mst fixups "
1161 "(inode 0x%lx, attribute type 0x%x, "
1162 "page index 0x%lx, page offset 0x%x)!"
1163 " Unmount and run chkdsk.", vi->i_ino,
1164 ni->type, page->index, ofs);
1165 /*
1166 * Mark all the buffers in this record clean as we do
1167 * not want to write corrupt data to disk.
1168 */
1169 do {
1170 clear_buffer_dirty(bhs[i]);
1171 bhs[i] = NULL;
1172 } while (++i % bhs_per_rec);
1173 continue;
1174 }
1175 nr_recs++;
1176 }
1177 /* If no records are to be written out, we are done. */
1178 if (!nr_recs)
1179 goto unm_done;
1180 flush_dcache_page(page);
1181 /* Lock buffers and start synchronous write i/o on them. */
1182 for (i = 0; i < nr_bhs; i++) {
1183 tbh = bhs[i];
1184 if (!tbh)
1185 continue;
1186 if (unlikely(test_set_buffer_locked(tbh)))
1187 BUG();
1188 /* The buffer dirty state is now irrelevant, just clean it. */
1189 clear_buffer_dirty(tbh);
1190 BUG_ON(!buffer_uptodate(tbh));
1191 BUG_ON(!buffer_mapped(tbh));
1192 get_bh(tbh);
1193 tbh->b_end_io = end_buffer_write_sync;
1194 submit_bh(WRITE, tbh);
1195 }
1196 /* Synchronize the mft mirror now if not @sync. */
1197 if (is_mft && !sync)
1198 goto do_mirror;
1199do_wait:
1200 /* Wait on i/o completion of buffers. */
1201 for (i = 0; i < nr_bhs; i++) {
1202 tbh = bhs[i];
1203 if (!tbh)
1204 continue;
1205 wait_on_buffer(tbh);
1206 if (unlikely(!buffer_uptodate(tbh))) {
1207 ntfs_error(vol->sb, "I/O error while writing ntfs "
1208 "record buffer (inode 0x%lx, "
1209 "attribute type 0x%x, page index "
1210 "0x%lx, page offset 0x%lx)! Unmount "
1211 "and run chkdsk.", vi->i_ino, ni->type,
1212 page->index, bh_offset(tbh));
1213 if (!err || err == -ENOMEM)
1214 err = -EIO;
1215 /*
1216 * Set the buffer uptodate so the page and buffer
1217 * states do not become out of sync.
1218 */
1219 set_buffer_uptodate(tbh);
1220 }
1221 }
1222 /* If @sync, now synchronize the mft mirror. */
1223 if (is_mft && sync) {
1224do_mirror:
1225 for (i = 0; i < nr_bhs; i++) {
1226 unsigned long mft_no;
1227 unsigned int ofs;
1228
1229 /*
1230 * Skip buffers which are not at the beginning of
1231 * records.
1232 */
1233 if (i % bhs_per_rec)
1234 continue;
1235 tbh = bhs[i];
1236 /* Skip removed buffers (and hence records). */
1237 if (!tbh)
1238 continue;
1239 ofs = bh_offset(tbh);
1240 /* Get the mft record number. */
1241 mft_no = (((s64)page->index << PAGE_CACHE_SHIFT) + ofs)
1242 >> rec_size_bits;
1243 if (mft_no < vol->mftmirr_size)
1244 ntfs_sync_mft_mirror(vol, mft_no,
1245 (MFT_RECORD*)(kaddr + ofs),
1246 sync);
1247 }
1248 if (!sync)
1249 goto do_wait;
1250 }
1251 /* Remove the mst protection fixups again. */
1252 for (i = 0; i < nr_bhs; i++) {
1253 if (!(i % bhs_per_rec)) {
1254 tbh = bhs[i];
1255 if (!tbh)
1256 continue;
1257 post_write_mst_fixup((NTFS_RECORD*)(kaddr +
1258 bh_offset(tbh)));
1259 }
1260 }
1261 flush_dcache_page(page);
1262unm_done:
1263 /* Unlock any locked inodes. */
1264 while (nr_locked_nis-- > 0) {
1265 ntfs_inode *tni, *base_tni;
1266
1267 tni = locked_nis[nr_locked_nis];
1268 /* Get the base inode. */
Ingo Molnar4e5e5292006-03-23 16:57:48 +00001269 mutex_lock(&tni->extent_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001270 if (tni->nr_extents >= 0)
1271 base_tni = tni;
1272 else {
1273 base_tni = tni->ext.base_ntfs_ino;
1274 BUG_ON(!base_tni);
1275 }
Ingo Molnar4e5e5292006-03-23 16:57:48 +00001276 mutex_unlock(&tni->extent_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001277 ntfs_debug("Unlocking %s inode 0x%lx.",
1278 tni == base_tni ? "base" : "extent",
1279 tni->mft_no);
Ingo Molnar4e5e5292006-03-23 16:57:48 +00001280 mutex_unlock(&tni->mrec_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001281 atomic_dec(&tni->count);
1282 iput(VFS_I(base_tni));
1283 }
1284 SetPageUptodate(page);
1285 kunmap(page);
1286done:
1287 if (unlikely(err && err != -ENOMEM)) {
1288 /*
1289 * Set page error if there is only one ntfs record in the page.
1290 * Otherwise we would loose per-record granularity.
1291 */
1292 if (ni->itype.index.block_size == PAGE_CACHE_SIZE)
1293 SetPageError(page);
1294 NVolSetErrors(vol);
1295 }
1296 if (page_is_dirty) {
1297 ntfs_debug("Page still contains one or more dirty ntfs "
1298 "records. Redirtying the page starting at "
1299 "record 0x%lx.", page->index <<
1300 (PAGE_CACHE_SHIFT - rec_size_bits));
1301 redirty_page_for_writepage(wbc, page);
1302 unlock_page(page);
1303 } else {
1304 /*
1305 * Keep the VM happy. This must be done otherwise the
1306 * radix-tree tag PAGECACHE_TAG_DIRTY remains set even though
1307 * the page is clean.
1308 */
1309 BUG_ON(PageWriteback(page));
1310 set_page_writeback(page);
1311 unlock_page(page);
1312 end_page_writeback(page);
1313 }
1314 if (likely(!err))
1315 ntfs_debug("Done.");
1316 return err;
1317}
1318
1319/**
1320 * ntfs_writepage - write a @page to the backing store
1321 * @page: page cache page to write out
1322 * @wbc: writeback control structure
1323 *
1324 * This is called from the VM when it wants to have a dirty ntfs page cache
1325 * page cleaned. The VM has already locked the page and marked it clean.
1326 *
1327 * For non-resident attributes, ntfs_writepage() writes the @page by calling
1328 * the ntfs version of the generic block_write_full_page() function,
1329 * ntfs_write_block(), which in turn if necessary creates and writes the
1330 * buffers associated with the page asynchronously.
1331 *
1332 * For resident attributes, OTOH, ntfs_writepage() writes the @page by copying
1333 * the data to the mft record (which at this stage is most likely in memory).
1334 * The mft record is then marked dirty and written out asynchronously via the
1335 * vfs inode dirty code path for the inode the mft record belongs to or via the
1336 * vm page dirty code path for the page the mft record is in.
1337 *
1338 * Based on ntfs_readpage() and fs/buffer.c::block_write_full_page().
1339 *
1340 * Return 0 on success and -errno on error.
1341 */
1342static int ntfs_writepage(struct page *page, struct writeback_control *wbc)
1343{
1344 loff_t i_size;
Anton Altaparmakov149f0c52005-01-12 13:52:30 +00001345 struct inode *vi = page->mapping->host;
1346 ntfs_inode *base_ni = NULL, *ni = NTFS_I(vi);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001347 char *kaddr;
Anton Altaparmakov149f0c52005-01-12 13:52:30 +00001348 ntfs_attr_search_ctx *ctx = NULL;
1349 MFT_RECORD *m = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001350 u32 attr_len;
1351 int err;
1352
Anton Altaparmakov905685f2005-03-10 11:06:19 +00001353retry_writepage:
Linus Torvalds1da177e2005-04-16 15:20:36 -07001354 BUG_ON(!PageLocked(page));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001355 i_size = i_size_read(vi);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001356 /* Is the page fully outside i_size? (truncate in progress) */
1357 if (unlikely(page->index >= (i_size + PAGE_CACHE_SIZE - 1) >>
1358 PAGE_CACHE_SHIFT)) {
1359 /*
1360 * The page may have dirty, unmapped buffers. Make them
1361 * freeable here, so the page does not leak.
1362 */
1363 block_invalidatepage(page, 0);
1364 unlock_page(page);
1365 ntfs_debug("Write outside i_size - truncated?");
1366 return 0;
1367 }
Anton Altaparmakovbd45fdd2005-09-08 21:38:05 +01001368 /*
1369 * Only $DATA attributes can be encrypted and only unnamed $DATA
1370 * attributes can be compressed. Index root can have the flags set but
1371 * this means to create compressed/encrypted files, not that the
Anton Altaparmakov4e64c882005-09-19 09:38:41 +01001372 * attribute is compressed/encrypted. Note we need to check for
1373 * AT_INDEX_ALLOCATION since this is the type of both directory and
1374 * index inodes.
Anton Altaparmakovbd45fdd2005-09-08 21:38:05 +01001375 */
Anton Altaparmakov4e64c882005-09-19 09:38:41 +01001376 if (ni->type != AT_INDEX_ALLOCATION) {
Anton Altaparmakovbd45fdd2005-09-08 21:38:05 +01001377 /* If file is encrypted, deny access, just like NT4. */
1378 if (NInoEncrypted(ni)) {
1379 unlock_page(page);
1380 BUG_ON(ni->type != AT_DATA);
Anton Altaparmakov7d0ffdb2005-10-19 12:21:19 +01001381 ntfs_debug("Denying write access to encrypted file.");
Anton Altaparmakovbd45fdd2005-09-08 21:38:05 +01001382 return -EACCES;
1383 }
1384 /* Compressed data streams are handled in compress.c. */
1385 if (NInoNonResident(ni) && NInoCompressed(ni)) {
1386 BUG_ON(ni->type != AT_DATA);
1387 BUG_ON(ni->name_len);
1388 // TODO: Implement and replace this with
1389 // return ntfs_write_compressed_block(page);
1390 unlock_page(page);
1391 ntfs_error(vi->i_sb, "Writing to compressed files is "
1392 "not supported yet. Sorry.");
1393 return -EOPNOTSUPP;
1394 }
1395 // TODO: Implement and remove this check.
1396 if (NInoNonResident(ni) && NInoSparse(ni)) {
1397 unlock_page(page);
1398 ntfs_error(vi->i_sb, "Writing to sparse files is not "
1399 "supported yet. Sorry.");
1400 return -EOPNOTSUPP;
1401 }
1402 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001403 /* NInoNonResident() == NInoIndexAllocPresent() */
1404 if (NInoNonResident(ni)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001405 /* We have to zero every time due to mmap-at-end-of-file. */
1406 if (page->index >= (i_size >> PAGE_CACHE_SHIFT)) {
1407 /* The page straddles i_size. */
1408 unsigned int ofs = i_size & ~PAGE_CACHE_MASK;
Nate Dillere3bf4602007-05-12 10:36:54 -07001409 zero_user_page(page, ofs, PAGE_CACHE_SIZE - ofs,
1410 KM_USER0);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001411 }
1412 /* Handle mst protected attributes. */
1413 if (NInoMstProtected(ni))
1414 return ntfs_write_mst_block(page, wbc);
Anton Altaparmakovbd45fdd2005-09-08 21:38:05 +01001415 /* Normal, non-resident data stream. */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001416 return ntfs_write_block(page, wbc);
1417 }
1418 /*
Anton Altaparmakovbd45fdd2005-09-08 21:38:05 +01001419 * Attribute is resident, implying it is not compressed, encrypted, or
1420 * mst protected. This also means the attribute is smaller than an mft
1421 * record and hence smaller than a page, so can simply return error on
1422 * any pages with index above 0. Note the attribute can actually be
1423 * marked compressed but if it is resident the actual data is not
1424 * compressed so we are ok to ignore the compressed flag here.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001425 */
1426 BUG_ON(page_has_buffers(page));
1427 BUG_ON(!PageUptodate(page));
1428 if (unlikely(page->index > 0)) {
1429 ntfs_error(vi->i_sb, "BUG()! page->index (0x%lx) > 0. "
1430 "Aborting write.", page->index);
1431 BUG_ON(PageWriteback(page));
1432 set_page_writeback(page);
1433 unlock_page(page);
1434 end_page_writeback(page);
1435 return -EIO;
1436 }
1437 if (!NInoAttr(ni))
1438 base_ni = ni;
1439 else
1440 base_ni = ni->ext.base_ntfs_ino;
1441 /* Map, pin, and lock the mft record. */
1442 m = map_mft_record(base_ni);
1443 if (IS_ERR(m)) {
1444 err = PTR_ERR(m);
1445 m = NULL;
1446 ctx = NULL;
1447 goto err_out;
1448 }
Anton Altaparmakov905685f2005-03-10 11:06:19 +00001449 /*
1450 * If a parallel write made the attribute non-resident, drop the mft
1451 * record and retry the writepage.
1452 */
1453 if (unlikely(NInoNonResident(ni))) {
1454 unmap_mft_record(base_ni);
1455 goto retry_writepage;
1456 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001457 ctx = ntfs_attr_get_search_ctx(base_ni, m);
1458 if (unlikely(!ctx)) {
1459 err = -ENOMEM;
1460 goto err_out;
1461 }
1462 err = ntfs_attr_lookup(ni->type, ni->name, ni->name_len,
1463 CASE_SENSITIVE, 0, NULL, 0, ctx);
1464 if (unlikely(err))
1465 goto err_out;
1466 /*
1467 * Keep the VM happy. This must be done otherwise the radix-tree tag
1468 * PAGECACHE_TAG_DIRTY remains set even though the page is clean.
1469 */
1470 BUG_ON(PageWriteback(page));
1471 set_page_writeback(page);
1472 unlock_page(page);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001473 attr_len = le32_to_cpu(ctx->attr->data.resident.value_length);
Anton Altaparmakov07a4e2d2005-01-12 13:08:26 +00001474 i_size = i_size_read(vi);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001475 if (unlikely(attr_len > i_size)) {
Anton Altaparmakovf6098cf2005-09-19 09:41:39 +01001476 /* Race with shrinking truncate or a failed truncate. */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001477 attr_len = i_size;
Anton Altaparmakovf6098cf2005-09-19 09:41:39 +01001478 /*
1479 * If the truncate failed, fix it up now. If a concurrent
1480 * truncate, we do its job, so it does not have to do anything.
1481 */
1482 err = ntfs_resident_attr_value_resize(ctx->mrec, ctx->attr,
1483 attr_len);
1484 /* Shrinking cannot fail. */
1485 BUG_ON(err);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001486 }
Anton Altaparmakovf40661b2005-01-13 16:03:38 +00001487 kaddr = kmap_atomic(page, KM_USER0);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001488 /* Copy the data from the page to the mft record. */
1489 memcpy((u8*)ctx->attr +
1490 le16_to_cpu(ctx->attr->data.resident.value_offset),
1491 kaddr, attr_len);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001492 /* Zero out of bounds area in the page cache page. */
1493 memset(kaddr + attr_len, 0, PAGE_CACHE_SIZE - attr_len);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001494 kunmap_atomic(kaddr, KM_USER0);
Anton Altaparmakovf6098cf2005-09-19 09:41:39 +01001495 flush_dcache_page(page);
Anton Altaparmakov7d0ffdb2005-10-19 12:21:19 +01001496 flush_dcache_mft_record_page(ctx->ntfs_ino);
Anton Altaparmakovf6098cf2005-09-19 09:41:39 +01001497 /* We are done with the page. */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001498 end_page_writeback(page);
Anton Altaparmakovf6098cf2005-09-19 09:41:39 +01001499 /* Finally, mark the mft record dirty, so it gets written back. */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001500 mark_mft_record_dirty(ctx->ntfs_ino);
1501 ntfs_attr_put_search_ctx(ctx);
1502 unmap_mft_record(base_ni);
1503 return 0;
1504err_out:
1505 if (err == -ENOMEM) {
1506 ntfs_warning(vi->i_sb, "Error allocating memory. Redirtying "
1507 "page so we try again later.");
1508 /*
1509 * Put the page back on mapping->dirty_pages, but leave its
1510 * buffers' dirty state as-is.
1511 */
1512 redirty_page_for_writepage(wbc, page);
1513 err = 0;
1514 } else {
1515 ntfs_error(vi->i_sb, "Resident attribute write failed with "
Anton Altaparmakov149f0c52005-01-12 13:52:30 +00001516 "error %i.", err);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001517 SetPageError(page);
Anton Altaparmakov149f0c52005-01-12 13:52:30 +00001518 NVolSetErrors(ni->vol);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001519 }
1520 unlock_page(page);
1521 if (ctx)
1522 ntfs_attr_put_search_ctx(ctx);
1523 if (m)
1524 unmap_mft_record(base_ni);
1525 return err;
1526}
1527
Linus Torvalds1da177e2005-04-16 15:20:36 -07001528#endif /* NTFS_RW */
1529
1530/**
1531 * ntfs_aops - general address space operations for inodes and attributes
1532 */
Christoph Hellwigf5e54d62006-06-28 04:26:44 -07001533const struct address_space_operations ntfs_aops = {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001534 .readpage = ntfs_readpage, /* Fill page with data. */
1535 .sync_page = block_sync_page, /* Currently, just unplugs the
1536 disk request queue. */
1537#ifdef NTFS_RW
1538 .writepage = ntfs_writepage, /* Write dirty page to disk. */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001539#endif /* NTFS_RW */
Anton Altaparmakov78264bd2006-03-23 15:06:18 +00001540 .migratepage = buffer_migrate_page, /* Move a page cache page from
1541 one physical page to an
1542 other. */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001543};
1544
1545/**
1546 * ntfs_mst_aops - general address space operations for mst protecteed inodes
1547 * and attributes
1548 */
Christoph Hellwigf5e54d62006-06-28 04:26:44 -07001549const struct address_space_operations ntfs_mst_aops = {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001550 .readpage = ntfs_readpage, /* Fill page with data. */
1551 .sync_page = block_sync_page, /* Currently, just unplugs the
1552 disk request queue. */
1553#ifdef NTFS_RW
1554 .writepage = ntfs_writepage, /* Write dirty page to disk. */
1555 .set_page_dirty = __set_page_dirty_nobuffers, /* Set the page dirty
1556 without touching the buffers
1557 belonging to the page. */
1558#endif /* NTFS_RW */
Anton Altaparmakov78264bd2006-03-23 15:06:18 +00001559 .migratepage = buffer_migrate_page, /* Move a page cache page from
1560 one physical page to an
1561 other. */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001562};
1563
1564#ifdef NTFS_RW
1565
1566/**
1567 * mark_ntfs_record_dirty - mark an ntfs record dirty
1568 * @page: page containing the ntfs record to mark dirty
1569 * @ofs: byte offset within @page at which the ntfs record begins
1570 *
1571 * Set the buffers and the page in which the ntfs record is located dirty.
1572 *
1573 * The latter also marks the vfs inode the ntfs record belongs to dirty
1574 * (I_DIRTY_PAGES only).
1575 *
1576 * If the page does not have buffers, we create them and set them uptodate.
1577 * The page may not be locked which is why we need to handle the buffers under
1578 * the mapping->private_lock. Once the buffers are marked dirty we no longer
1579 * need the lock since try_to_free_buffers() does not free dirty buffers.
1580 */
1581void mark_ntfs_record_dirty(struct page *page, const unsigned int ofs) {
1582 struct address_space *mapping = page->mapping;
1583 ntfs_inode *ni = NTFS_I(mapping->host);
1584 struct buffer_head *bh, *head, *buffers_to_free = NULL;
1585 unsigned int end, bh_size, bh_ofs;
1586
1587 BUG_ON(!PageUptodate(page));
1588 end = ofs + ni->itype.index.block_size;
Anton Altaparmakov78af34f2006-02-24 10:32:33 +00001589 bh_size = VFS_I(ni)->i_sb->s_blocksize;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001590 spin_lock(&mapping->private_lock);
1591 if (unlikely(!page_has_buffers(page))) {
1592 spin_unlock(&mapping->private_lock);
1593 bh = head = alloc_page_buffers(page, bh_size, 1);
1594 spin_lock(&mapping->private_lock);
1595 if (likely(!page_has_buffers(page))) {
1596 struct buffer_head *tail;
1597
1598 do {
1599 set_buffer_uptodate(bh);
1600 tail = bh;
1601 bh = bh->b_this_page;
1602 } while (bh);
1603 tail->b_this_page = head;
1604 attach_page_buffers(page, head);
1605 } else
1606 buffers_to_free = bh;
1607 }
1608 bh = head = page_buffers(page);
Anton Altaparmakova01ac532005-09-08 22:08:11 +01001609 BUG_ON(!bh);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001610 do {
1611 bh_ofs = bh_offset(bh);
1612 if (bh_ofs + bh_size <= ofs)
1613 continue;
1614 if (unlikely(bh_ofs >= end))
1615 break;
1616 set_buffer_dirty(bh);
1617 } while ((bh = bh->b_this_page) != head);
1618 spin_unlock(&mapping->private_lock);
1619 __set_page_dirty_nobuffers(page);
1620 if (unlikely(buffers_to_free)) {
1621 do {
1622 bh = buffers_to_free->b_this_page;
1623 free_buffer_head(buffers_to_free);
1624 buffers_to_free = bh;
1625 } while (buffers_to_free);
1626 }
1627}
1628
1629#endif /* NTFS_RW */