Commit | Line | Data |
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a1d312de | 1 | // SPDX-License-Identifier: GPL-2.0-or-later |
1da177e4 LT |
2 | /** |
3 | * aops.c - NTFS kernel address space operations and page cache handling. | |
1da177e4 | 4 | * |
ce1bafa0 | 5 | * Copyright (c) 2001-2014 Anton Altaparmakov and Tuxera Inc. |
1da177e4 | 6 | * Copyright (c) 2002 Richard Russon |
1da177e4 LT |
7 | */ |
8 | ||
9 | #include <linux/errno.h> | |
78264bd9 | 10 | #include <linux/fs.h> |
5a0e3ad6 | 11 | #include <linux/gfp.h> |
1da177e4 LT |
12 | #include <linux/mm.h> |
13 | #include <linux/pagemap.h> | |
14 | #include <linux/swap.h> | |
15 | #include <linux/buffer_head.h> | |
16 | #include <linux/writeback.h> | |
b4012a98 | 17 | #include <linux/bit_spinlock.h> |
be297968 | 18 | #include <linux/bio.h> |
1da177e4 LT |
19 | |
20 | #include "aops.h" | |
21 | #include "attrib.h" | |
22 | #include "debug.h" | |
23 | #include "inode.h" | |
24 | #include "mft.h" | |
25 | #include "runlist.h" | |
26 | #include "types.h" | |
27 | #include "ntfs.h" | |
28 | ||
29 | /** | |
30 | * ntfs_end_buffer_async_read - async io completion for reading attributes | |
31 | * @bh: buffer head on which io is completed | |
32 | * @uptodate: whether @bh is now uptodate or not | |
33 | * | |
34 | * Asynchronous I/O completion handler for reading pages belonging to the | |
35 | * attribute address space of an inode. The inodes can either be files or | |
36 | * directories or they can be fake inodes describing some attribute. | |
37 | * | |
38 | * If NInoMstProtected(), perform the post read mst fixups when all IO on the | |
39 | * page has been completed and mark the page uptodate or set the error bit on | |
40 | * the page. To determine the size of the records that need fixing up, we | |
41 | * cheat a little bit by setting the index_block_size in ntfs_inode to the ntfs | |
42 | * record size, and index_block_size_bits, to the log(base 2) of the ntfs | |
43 | * record size. | |
44 | */ | |
45 | static void ntfs_end_buffer_async_read(struct buffer_head *bh, int uptodate) | |
46 | { | |
1da177e4 | 47 | unsigned long flags; |
e604635c | 48 | struct buffer_head *first, *tmp; |
1da177e4 | 49 | struct page *page; |
f6098cf4 | 50 | struct inode *vi; |
1da177e4 LT |
51 | ntfs_inode *ni; |
52 | int page_uptodate = 1; | |
53 | ||
54 | page = bh->b_page; | |
f6098cf4 AA |
55 | vi = page->mapping->host; |
56 | ni = NTFS_I(vi); | |
1da177e4 LT |
57 | |
58 | if (likely(uptodate)) { | |
f6098cf4 AA |
59 | loff_t i_size; |
60 | s64 file_ofs, init_size; | |
1da177e4 LT |
61 | |
62 | set_buffer_uptodate(bh); | |
63 | ||
09cbfeaf | 64 | file_ofs = ((s64)page->index << PAGE_SHIFT) + |
1da177e4 | 65 | bh_offset(bh); |
07a4e2da | 66 | read_lock_irqsave(&ni->size_lock, flags); |
f6098cf4 AA |
67 | init_size = ni->initialized_size; |
68 | i_size = i_size_read(vi); | |
07a4e2da | 69 | read_unlock_irqrestore(&ni->size_lock, flags); |
f6098cf4 AA |
70 | if (unlikely(init_size > i_size)) { |
71 | /* Race with shrinking truncate. */ | |
72 | init_size = i_size; | |
73 | } | |
1da177e4 | 74 | /* Check for the current buffer head overflowing. */ |
f6098cf4 | 75 | if (unlikely(file_ofs + bh->b_size > init_size)) { |
f6098cf4 | 76 | int ofs; |
eebd2aa3 | 77 | void *kaddr; |
f6098cf4 AA |
78 | |
79 | ofs = 0; | |
80 | if (file_ofs < init_size) | |
81 | ofs = init_size - file_ofs; | |
a3ac1414 | 82 | kaddr = kmap_atomic(page); |
eebd2aa3 CL |
83 | memset(kaddr + bh_offset(bh) + ofs, 0, |
84 | bh->b_size - ofs); | |
85 | flush_dcache_page(page); | |
a3ac1414 | 86 | kunmap_atomic(kaddr); |
1da177e4 LT |
87 | } |
88 | } else { | |
89 | clear_buffer_uptodate(bh); | |
e604635c | 90 | SetPageError(page); |
f6098cf4 AA |
91 | ntfs_error(ni->vol->sb, "Buffer I/O error, logical block " |
92 | "0x%llx.", (unsigned long long)bh->b_blocknr); | |
1da177e4 | 93 | } |
e604635c AA |
94 | first = page_buffers(page); |
95 | local_irq_save(flags); | |
96 | bit_spin_lock(BH_Uptodate_Lock, &first->b_state); | |
1da177e4 LT |
97 | clear_buffer_async_read(bh); |
98 | unlock_buffer(bh); | |
99 | tmp = bh; | |
100 | do { | |
101 | if (!buffer_uptodate(tmp)) | |
102 | page_uptodate = 0; | |
103 | if (buffer_async_read(tmp)) { | |
104 | if (likely(buffer_locked(tmp))) | |
105 | goto still_busy; | |
106 | /* Async buffers must be locked. */ | |
107 | BUG(); | |
108 | } | |
109 | tmp = tmp->b_this_page; | |
110 | } while (tmp != bh); | |
e604635c AA |
111 | bit_spin_unlock(BH_Uptodate_Lock, &first->b_state); |
112 | local_irq_restore(flags); | |
1da177e4 LT |
113 | /* |
114 | * If none of the buffers had errors then we can set the page uptodate, | |
115 | * but we first have to perform the post read mst fixups, if the | |
116 | * attribute is mst protected, i.e. if NInoMstProteced(ni) is true. | |
117 | * Note we ignore fixup errors as those are detected when | |
118 | * map_mft_record() is called which gives us per record granularity | |
119 | * rather than per page granularity. | |
120 | */ | |
121 | if (!NInoMstProtected(ni)) { | |
122 | if (likely(page_uptodate && !PageError(page))) | |
123 | SetPageUptodate(page); | |
124 | } else { | |
f6098cf4 | 125 | u8 *kaddr; |
1da177e4 LT |
126 | unsigned int i, recs; |
127 | u32 rec_size; | |
128 | ||
129 | rec_size = ni->itype.index.block_size; | |
09cbfeaf | 130 | recs = PAGE_SIZE / rec_size; |
1da177e4 LT |
131 | /* Should have been verified before we got here... */ |
132 | BUG_ON(!recs); | |
a3ac1414 | 133 | kaddr = kmap_atomic(page); |
1da177e4 | 134 | for (i = 0; i < recs; i++) |
f6098cf4 | 135 | post_read_mst_fixup((NTFS_RECORD*)(kaddr + |
1da177e4 | 136 | i * rec_size), rec_size); |
a3ac1414 | 137 | kunmap_atomic(kaddr); |
1da177e4 | 138 | flush_dcache_page(page); |
b6ad6c52 | 139 | if (likely(page_uptodate && !PageError(page))) |
1da177e4 LT |
140 | SetPageUptodate(page); |
141 | } | |
142 | unlock_page(page); | |
143 | return; | |
144 | still_busy: | |
e604635c AA |
145 | bit_spin_unlock(BH_Uptodate_Lock, &first->b_state); |
146 | local_irq_restore(flags); | |
1da177e4 LT |
147 | return; |
148 | } | |
149 | ||
150 | /** | |
151 | * ntfs_read_block - fill a @page of an address space with data | |
152 | * @page: page cache page to fill with data | |
153 | * | |
154 | * Fill the page @page of the address space belonging to the @page->host inode. | |
155 | * We read each buffer asynchronously and when all buffers are read in, our io | |
156 | * completion handler ntfs_end_buffer_read_async(), if required, automatically | |
157 | * applies the mst fixups to the page before finally marking it uptodate and | |
158 | * unlocking it. | |
159 | * | |
160 | * We only enforce allocated_size limit because i_size is checked for in | |
161 | * generic_file_read(). | |
162 | * | |
163 | * Return 0 on success and -errno on error. | |
164 | * | |
165 | * Contains an adapted version of fs/buffer.c::block_read_full_page(). | |
166 | */ | |
167 | static int ntfs_read_block(struct page *page) | |
168 | { | |
f6098cf4 | 169 | loff_t i_size; |
1da177e4 LT |
170 | VCN vcn; |
171 | LCN lcn; | |
f6098cf4 AA |
172 | s64 init_size; |
173 | struct inode *vi; | |
1da177e4 LT |
174 | ntfs_inode *ni; |
175 | ntfs_volume *vol; | |
176 | runlist_element *rl; | |
177 | struct buffer_head *bh, *head, *arr[MAX_BUF_PER_PAGE]; | |
178 | sector_t iblock, lblock, zblock; | |
07a4e2da | 179 | unsigned long flags; |
1da177e4 LT |
180 | unsigned int blocksize, vcn_ofs; |
181 | int i, nr; | |
182 | unsigned char blocksize_bits; | |
183 | ||
f6098cf4 AA |
184 | vi = page->mapping->host; |
185 | ni = NTFS_I(vi); | |
1da177e4 LT |
186 | vol = ni->vol; |
187 | ||
188 | /* $MFT/$DATA must have its complete runlist in memory at all times. */ | |
189 | BUG_ON(!ni->runlist.rl && !ni->mft_no && !NInoAttr(ni)); | |
190 | ||
78af34f0 AA |
191 | blocksize = vol->sb->s_blocksize; |
192 | blocksize_bits = vol->sb->s_blocksize_bits; | |
1da177e4 | 193 | |
a01ac532 | 194 | if (!page_has_buffers(page)) { |
1da177e4 | 195 | create_empty_buffers(page, blocksize, 0); |
a01ac532 AA |
196 | if (unlikely(!page_has_buffers(page))) { |
197 | unlock_page(page); | |
198 | return -ENOMEM; | |
199 | } | |
1da177e4 | 200 | } |
a01ac532 AA |
201 | bh = head = page_buffers(page); |
202 | BUG_ON(!bh); | |
1da177e4 | 203 | |
f6098cf4 AA |
204 | /* |
205 | * We may be racing with truncate. To avoid some of the problems we | |
206 | * now take a snapshot of the various sizes and use those for the whole | |
207 | * of the function. In case of an extending truncate it just means we | |
208 | * may leave some buffers unmapped which are now allocated. This is | |
209 | * not a problem since these buffers will just get mapped when a write | |
210 | * occurs. In case of a shrinking truncate, we will detect this later | |
211 | * on due to the runlist being incomplete and if the page is being | |
212 | * fully truncated, truncate will throw it away as soon as we unlock | |
213 | * it so no need to worry what we do with it. | |
214 | */ | |
09cbfeaf | 215 | iblock = (s64)page->index << (PAGE_SHIFT - blocksize_bits); |
07a4e2da | 216 | read_lock_irqsave(&ni->size_lock, flags); |
1da177e4 | 217 | lblock = (ni->allocated_size + blocksize - 1) >> blocksize_bits; |
f6098cf4 AA |
218 | init_size = ni->initialized_size; |
219 | i_size = i_size_read(vi); | |
07a4e2da | 220 | read_unlock_irqrestore(&ni->size_lock, flags); |
f6098cf4 AA |
221 | if (unlikely(init_size > i_size)) { |
222 | /* Race with shrinking truncate. */ | |
223 | init_size = i_size; | |
224 | } | |
225 | zblock = (init_size + blocksize - 1) >> blocksize_bits; | |
1da177e4 LT |
226 | |
227 | /* Loop through all the buffers in the page. */ | |
228 | rl = NULL; | |
229 | nr = i = 0; | |
230 | do { | |
e3bf460f | 231 | int err = 0; |
1da177e4 LT |
232 | |
233 | if (unlikely(buffer_uptodate(bh))) | |
234 | continue; | |
235 | if (unlikely(buffer_mapped(bh))) { | |
236 | arr[nr++] = bh; | |
237 | continue; | |
238 | } | |
239 | bh->b_bdev = vol->sb->s_bdev; | |
240 | /* Is the block within the allowed limits? */ | |
241 | if (iblock < lblock) { | |
c49c3111 | 242 | bool is_retry = false; |
1da177e4 LT |
243 | |
244 | /* Convert iblock into corresponding vcn and offset. */ | |
245 | vcn = (VCN)iblock << blocksize_bits >> | |
246 | vol->cluster_size_bits; | |
247 | vcn_ofs = ((VCN)iblock << blocksize_bits) & | |
248 | vol->cluster_size_mask; | |
249 | if (!rl) { | |
250 | lock_retry_remap: | |
251 | down_read(&ni->runlist.lock); | |
252 | rl = ni->runlist.rl; | |
253 | } | |
254 | if (likely(rl != NULL)) { | |
255 | /* Seek to element containing target vcn. */ | |
256 | while (rl->length && rl[1].vcn <= vcn) | |
257 | rl++; | |
258 | lcn = ntfs_rl_vcn_to_lcn(rl, vcn); | |
259 | } else | |
260 | lcn = LCN_RL_NOT_MAPPED; | |
261 | /* Successful remap. */ | |
262 | if (lcn >= 0) { | |
263 | /* Setup buffer head to correct block. */ | |
264 | bh->b_blocknr = ((lcn << vol->cluster_size_bits) | |
265 | + vcn_ofs) >> blocksize_bits; | |
266 | set_buffer_mapped(bh); | |
267 | /* Only read initialized data blocks. */ | |
268 | if (iblock < zblock) { | |
269 | arr[nr++] = bh; | |
270 | continue; | |
271 | } | |
272 | /* Fully non-initialized data block, zero it. */ | |
273 | goto handle_zblock; | |
274 | } | |
275 | /* It is a hole, need to zero it. */ | |
276 | if (lcn == LCN_HOLE) | |
277 | goto handle_hole; | |
278 | /* If first try and runlist unmapped, map and retry. */ | |
279 | if (!is_retry && lcn == LCN_RL_NOT_MAPPED) { | |
c49c3111 | 280 | is_retry = true; |
1da177e4 LT |
281 | /* |
282 | * Attempt to map runlist, dropping lock for | |
283 | * the duration. | |
284 | */ | |
285 | up_read(&ni->runlist.lock); | |
286 | err = ntfs_map_runlist(ni, vcn); | |
287 | if (likely(!err)) | |
288 | goto lock_retry_remap; | |
289 | rl = NULL; | |
9f993fe4 AA |
290 | } else if (!rl) |
291 | up_read(&ni->runlist.lock); | |
8273d5d4 AA |
292 | /* |
293 | * If buffer is outside the runlist, treat it as a | |
294 | * hole. This can happen due to concurrent truncate | |
295 | * for example. | |
296 | */ | |
297 | if (err == -ENOENT || lcn == LCN_ENOENT) { | |
298 | err = 0; | |
299 | goto handle_hole; | |
300 | } | |
1da177e4 | 301 | /* Hard error, zero out region. */ |
8273d5d4 AA |
302 | if (!err) |
303 | err = -EIO; | |
1da177e4 LT |
304 | bh->b_blocknr = -1; |
305 | SetPageError(page); | |
306 | ntfs_error(vol->sb, "Failed to read from inode 0x%lx, " | |
307 | "attribute type 0x%x, vcn 0x%llx, " | |
308 | "offset 0x%x because its location on " | |
309 | "disk could not be determined%s " | |
8273d5d4 | 310 | "(error code %i).", ni->mft_no, |
1da177e4 LT |
311 | ni->type, (unsigned long long)vcn, |
312 | vcn_ofs, is_retry ? " even after " | |
8273d5d4 | 313 | "retrying" : "", err); |
1da177e4 LT |
314 | } |
315 | /* | |
316 | * Either iblock was outside lblock limits or | |
317 | * ntfs_rl_vcn_to_lcn() returned error. Just zero that portion | |
318 | * of the page and set the buffer uptodate. | |
319 | */ | |
320 | handle_hole: | |
321 | bh->b_blocknr = -1UL; | |
322 | clear_buffer_mapped(bh); | |
323 | handle_zblock: | |
eebd2aa3 | 324 | zero_user(page, i * blocksize, blocksize); |
8273d5d4 AA |
325 | if (likely(!err)) |
326 | set_buffer_uptodate(bh); | |
1da177e4 LT |
327 | } while (i++, iblock++, (bh = bh->b_this_page) != head); |
328 | ||
329 | /* Release the lock if we took it. */ | |
330 | if (rl) | |
331 | up_read(&ni->runlist.lock); | |
332 | ||
333 | /* Check we have at least one buffer ready for i/o. */ | |
334 | if (nr) { | |
335 | struct buffer_head *tbh; | |
336 | ||
337 | /* Lock the buffers. */ | |
338 | for (i = 0; i < nr; i++) { | |
339 | tbh = arr[i]; | |
340 | lock_buffer(tbh); | |
341 | tbh->b_end_io = ntfs_end_buffer_async_read; | |
342 | set_buffer_async_read(tbh); | |
343 | } | |
344 | /* Finally, start i/o on the buffers. */ | |
345 | for (i = 0; i < nr; i++) { | |
346 | tbh = arr[i]; | |
347 | if (likely(!buffer_uptodate(tbh))) | |
2a222ca9 | 348 | submit_bh(REQ_OP_READ, 0, tbh); |
1da177e4 LT |
349 | else |
350 | ntfs_end_buffer_async_read(tbh, 1); | |
351 | } | |
352 | return 0; | |
353 | } | |
354 | /* No i/o was scheduled on any of the buffers. */ | |
355 | if (likely(!PageError(page))) | |
356 | SetPageUptodate(page); | |
357 | else /* Signal synchronous i/o error. */ | |
358 | nr = -EIO; | |
359 | unlock_page(page); | |
360 | return nr; | |
361 | } | |
362 | ||
363 | /** | |
364 | * ntfs_readpage - fill a @page of a @file with data from the device | |
365 | * @file: open file to which the page @page belongs or NULL | |
366 | * @page: page cache page to fill with data | |
367 | * | |
368 | * For non-resident attributes, ntfs_readpage() fills the @page of the open | |
369 | * file @file by calling the ntfs version of the generic block_read_full_page() | |
370 | * function, ntfs_read_block(), which in turn creates and reads in the buffers | |
371 | * associated with the page asynchronously. | |
372 | * | |
373 | * For resident attributes, OTOH, ntfs_readpage() fills @page by copying the | |
374 | * data from the mft record (which at this stage is most likely in memory) and | |
375 | * fills the remainder with zeroes. Thus, in this case, I/O is synchronous, as | |
376 | * even if the mft record is not cached at this point in time, we need to wait | |
377 | * for it to be read in before we can do the copy. | |
378 | * | |
379 | * Return 0 on success and -errno on error. | |
380 | */ | |
381 | static int ntfs_readpage(struct file *file, struct page *page) | |
382 | { | |
f6098cf4 AA |
383 | loff_t i_size; |
384 | struct inode *vi; | |
1da177e4 | 385 | ntfs_inode *ni, *base_ni; |
bfab36e8 | 386 | u8 *addr; |
1da177e4 LT |
387 | ntfs_attr_search_ctx *ctx; |
388 | MFT_RECORD *mrec; | |
b6ad6c52 | 389 | unsigned long flags; |
1da177e4 LT |
390 | u32 attr_len; |
391 | int err = 0; | |
392 | ||
905685f6 | 393 | retry_readpage: |
1da177e4 | 394 | BUG_ON(!PageLocked(page)); |
ebab8990 AA |
395 | vi = page->mapping->host; |
396 | i_size = i_size_read(vi); | |
397 | /* Is the page fully outside i_size? (truncate in progress) */ | |
09cbfeaf KS |
398 | if (unlikely(page->index >= (i_size + PAGE_SIZE - 1) >> |
399 | PAGE_SHIFT)) { | |
400 | zero_user(page, 0, PAGE_SIZE); | |
ebab8990 AA |
401 | ntfs_debug("Read outside i_size - truncated?"); |
402 | goto done; | |
403 | } | |
1da177e4 LT |
404 | /* |
405 | * This can potentially happen because we clear PageUptodate() during | |
406 | * ntfs_writepage() of MstProtected() attributes. | |
407 | */ | |
408 | if (PageUptodate(page)) { | |
409 | unlock_page(page); | |
410 | return 0; | |
411 | } | |
f6098cf4 | 412 | ni = NTFS_I(vi); |
311120ec AA |
413 | /* |
414 | * Only $DATA attributes can be encrypted and only unnamed $DATA | |
415 | * attributes can be compressed. Index root can have the flags set but | |
416 | * this means to create compressed/encrypted files, not that the | |
4e64c886 AA |
417 | * attribute is compressed/encrypted. Note we need to check for |
418 | * AT_INDEX_ALLOCATION since this is the type of both directory and | |
419 | * index inodes. | |
311120ec | 420 | */ |
4e64c886 | 421 | if (ni->type != AT_INDEX_ALLOCATION) { |
311120ec AA |
422 | /* If attribute is encrypted, deny access, just like NT4. */ |
423 | if (NInoEncrypted(ni)) { | |
424 | BUG_ON(ni->type != AT_DATA); | |
425 | err = -EACCES; | |
426 | goto err_out; | |
427 | } | |
428 | /* Compressed data streams are handled in compress.c. */ | |
429 | if (NInoNonResident(ni) && NInoCompressed(ni)) { | |
430 | BUG_ON(ni->type != AT_DATA); | |
431 | BUG_ON(ni->name_len); | |
432 | return ntfs_read_compressed_block(page); | |
433 | } | |
434 | } | |
1da177e4 LT |
435 | /* NInoNonResident() == NInoIndexAllocPresent() */ |
436 | if (NInoNonResident(ni)) { | |
311120ec | 437 | /* Normal, non-resident data stream. */ |
1da177e4 LT |
438 | return ntfs_read_block(page); |
439 | } | |
440 | /* | |
441 | * Attribute is resident, implying it is not compressed or encrypted. | |
442 | * This also means the attribute is smaller than an mft record and | |
443 | * hence smaller than a page, so can simply zero out any pages with | |
311120ec AA |
444 | * index above 0. Note the attribute can actually be marked compressed |
445 | * but if it is resident the actual data is not compressed so we are | |
446 | * ok to ignore the compressed flag here. | |
1da177e4 | 447 | */ |
b6ad6c52 | 448 | if (unlikely(page->index > 0)) { |
09cbfeaf | 449 | zero_user(page, 0, PAGE_SIZE); |
1da177e4 LT |
450 | goto done; |
451 | } | |
452 | if (!NInoAttr(ni)) | |
453 | base_ni = ni; | |
454 | else | |
455 | base_ni = ni->ext.base_ntfs_ino; | |
456 | /* Map, pin, and lock the mft record. */ | |
457 | mrec = map_mft_record(base_ni); | |
458 | if (IS_ERR(mrec)) { | |
459 | err = PTR_ERR(mrec); | |
460 | goto err_out; | |
461 | } | |
905685f6 AA |
462 | /* |
463 | * If a parallel write made the attribute non-resident, drop the mft | |
464 | * record and retry the readpage. | |
465 | */ | |
466 | if (unlikely(NInoNonResident(ni))) { | |
467 | unmap_mft_record(base_ni); | |
468 | goto retry_readpage; | |
469 | } | |
1da177e4 LT |
470 | ctx = ntfs_attr_get_search_ctx(base_ni, mrec); |
471 | if (unlikely(!ctx)) { | |
472 | err = -ENOMEM; | |
473 | goto unm_err_out; | |
474 | } | |
475 | err = ntfs_attr_lookup(ni->type, ni->name, ni->name_len, | |
476 | CASE_SENSITIVE, 0, NULL, 0, ctx); | |
477 | if (unlikely(err)) | |
478 | goto put_unm_err_out; | |
479 | attr_len = le32_to_cpu(ctx->attr->data.resident.value_length); | |
b6ad6c52 AA |
480 | read_lock_irqsave(&ni->size_lock, flags); |
481 | if (unlikely(attr_len > ni->initialized_size)) | |
482 | attr_len = ni->initialized_size; | |
f6098cf4 | 483 | i_size = i_size_read(vi); |
b6ad6c52 | 484 | read_unlock_irqrestore(&ni->size_lock, flags); |
f6098cf4 AA |
485 | if (unlikely(attr_len > i_size)) { |
486 | /* Race with shrinking truncate. */ | |
487 | attr_len = i_size; | |
488 | } | |
a3ac1414 | 489 | addr = kmap_atomic(page); |
1da177e4 | 490 | /* Copy the data to the page. */ |
bfab36e8 | 491 | memcpy(addr, (u8*)ctx->attr + |
1da177e4 LT |
492 | le16_to_cpu(ctx->attr->data.resident.value_offset), |
493 | attr_len); | |
494 | /* Zero the remainder of the page. */ | |
09cbfeaf | 495 | memset(addr + attr_len, 0, PAGE_SIZE - attr_len); |
1da177e4 | 496 | flush_dcache_page(page); |
a3ac1414 | 497 | kunmap_atomic(addr); |
1da177e4 LT |
498 | put_unm_err_out: |
499 | ntfs_attr_put_search_ctx(ctx); | |
500 | unm_err_out: | |
501 | unmap_mft_record(base_ni); | |
502 | done: | |
503 | SetPageUptodate(page); | |
504 | err_out: | |
505 | unlock_page(page); | |
506 | return err; | |
507 | } | |
508 | ||
509 | #ifdef NTFS_RW | |
510 | ||
511 | /** | |
512 | * ntfs_write_block - write a @page to the backing store | |
513 | * @page: page cache page to write out | |
514 | * @wbc: writeback control structure | |
515 | * | |
516 | * This function is for writing pages belonging to non-resident, non-mst | |
517 | * protected attributes to their backing store. | |
518 | * | |
519 | * For a page with buffers, map and write the dirty buffers asynchronously | |
520 | * under page writeback. For a page without buffers, create buffers for the | |
521 | * page, then proceed as above. | |
522 | * | |
523 | * If a page doesn't have buffers the page dirty state is definitive. If a page | |
524 | * does have buffers, the page dirty state is just a hint, and the buffer dirty | |
525 | * state is definitive. (A hint which has rules: dirty buffers against a clean | |
526 | * page is illegal. Other combinations are legal and need to be handled. In | |
527 | * particular a dirty page containing clean buffers for example.) | |
528 | * | |
529 | * Return 0 on success and -errno on error. | |
530 | * | |
531 | * Based on ntfs_read_block() and __block_write_full_page(). | |
532 | */ | |
533 | static int ntfs_write_block(struct page *page, struct writeback_control *wbc) | |
534 | { | |
535 | VCN vcn; | |
536 | LCN lcn; | |
07a4e2da AA |
537 | s64 initialized_size; |
538 | loff_t i_size; | |
1da177e4 LT |
539 | sector_t block, dblock, iblock; |
540 | struct inode *vi; | |
541 | ntfs_inode *ni; | |
542 | ntfs_volume *vol; | |
543 | runlist_element *rl; | |
544 | struct buffer_head *bh, *head; | |
07a4e2da | 545 | unsigned long flags; |
1da177e4 LT |
546 | unsigned int blocksize, vcn_ofs; |
547 | int err; | |
c49c3111 | 548 | bool need_end_writeback; |
1da177e4 LT |
549 | unsigned char blocksize_bits; |
550 | ||
551 | vi = page->mapping->host; | |
552 | ni = NTFS_I(vi); | |
553 | vol = ni->vol; | |
554 | ||
555 | ntfs_debug("Entering for inode 0x%lx, attribute type 0x%x, page index " | |
556 | "0x%lx.", ni->mft_no, ni->type, page->index); | |
557 | ||
558 | BUG_ON(!NInoNonResident(ni)); | |
559 | BUG_ON(NInoMstProtected(ni)); | |
78af34f0 AA |
560 | blocksize = vol->sb->s_blocksize; |
561 | blocksize_bits = vol->sb->s_blocksize_bits; | |
1da177e4 LT |
562 | if (!page_has_buffers(page)) { |
563 | BUG_ON(!PageUptodate(page)); | |
564 | create_empty_buffers(page, blocksize, | |
565 | (1 << BH_Uptodate) | (1 << BH_Dirty)); | |
a01ac532 AA |
566 | if (unlikely(!page_has_buffers(page))) { |
567 | ntfs_warning(vol->sb, "Error allocating page " | |
568 | "buffers. Redirtying page so we try " | |
569 | "again later."); | |
570 | /* | |
571 | * Put the page back on mapping->dirty_pages, but leave | |
572 | * its buffers' dirty state as-is. | |
573 | */ | |
574 | redirty_page_for_writepage(wbc, page); | |
575 | unlock_page(page); | |
576 | return 0; | |
577 | } | |
1da177e4 LT |
578 | } |
579 | bh = head = page_buffers(page); | |
a01ac532 | 580 | BUG_ON(!bh); |
1da177e4 LT |
581 | |
582 | /* NOTE: Different naming scheme to ntfs_read_block()! */ | |
583 | ||
584 | /* The first block in the page. */ | |
09cbfeaf | 585 | block = (s64)page->index << (PAGE_SHIFT - blocksize_bits); |
1da177e4 | 586 | |
07a4e2da AA |
587 | read_lock_irqsave(&ni->size_lock, flags); |
588 | i_size = i_size_read(vi); | |
589 | initialized_size = ni->initialized_size; | |
590 | read_unlock_irqrestore(&ni->size_lock, flags); | |
591 | ||
1da177e4 | 592 | /* The first out of bounds block for the data size. */ |
07a4e2da | 593 | dblock = (i_size + blocksize - 1) >> blocksize_bits; |
1da177e4 LT |
594 | |
595 | /* The last (fully or partially) initialized block. */ | |
07a4e2da | 596 | iblock = initialized_size >> blocksize_bits; |
1da177e4 LT |
597 | |
598 | /* | |
599 | * Be very careful. We have no exclusion from __set_page_dirty_buffers | |
600 | * here, and the (potentially unmapped) buffers may become dirty at | |
601 | * any time. If a buffer becomes dirty here after we've inspected it | |
602 | * then we just miss that fact, and the page stays dirty. | |
603 | * | |
604 | * Buffers outside i_size may be dirtied by __set_page_dirty_buffers; | |
605 | * handle that here by just cleaning them. | |
606 | */ | |
607 | ||
608 | /* | |
609 | * Loop through all the buffers in the page, mapping all the dirty | |
610 | * buffers to disk addresses and handling any aliases from the | |
611 | * underlying block device's mapping. | |
612 | */ | |
613 | rl = NULL; | |
614 | err = 0; | |
615 | do { | |
c49c3111 | 616 | bool is_retry = false; |
1da177e4 LT |
617 | |
618 | if (unlikely(block >= dblock)) { | |
619 | /* | |
620 | * Mapped buffers outside i_size will occur, because | |
621 | * this page can be outside i_size when there is a | |
622 | * truncate in progress. The contents of such buffers | |
623 | * were zeroed by ntfs_writepage(). | |
624 | * | |
625 | * FIXME: What about the small race window where | |
626 | * ntfs_writepage() has not done any clearing because | |
627 | * the page was within i_size but before we get here, | |
628 | * vmtruncate() modifies i_size? | |
629 | */ | |
630 | clear_buffer_dirty(bh); | |
631 | set_buffer_uptodate(bh); | |
632 | continue; | |
633 | } | |
634 | ||
635 | /* Clean buffers are not written out, so no need to map them. */ | |
636 | if (!buffer_dirty(bh)) | |
637 | continue; | |
638 | ||
639 | /* Make sure we have enough initialized size. */ | |
640 | if (unlikely((block >= iblock) && | |
07a4e2da | 641 | (initialized_size < i_size))) { |
1da177e4 LT |
642 | /* |
643 | * If this page is fully outside initialized size, zero | |
644 | * out all pages between the current initialized size | |
645 | * and the current page. Just use ntfs_readpage() to do | |
646 | * the zeroing transparently. | |
647 | */ | |
648 | if (block > iblock) { | |
649 | // TODO: | |
650 | // For each page do: | |
651 | // - read_cache_page() | |
652 | // Again for each page do: | |
653 | // - wait_on_page_locked() | |
654 | // - Check (PageUptodate(page) && | |
655 | // !PageError(page)) | |
656 | // Update initialized size in the attribute and | |
657 | // in the inode. | |
658 | // Again, for each page do: | |
659 | // __set_page_dirty_buffers(); | |
ea1754a0 | 660 | // put_page() |
1da177e4 LT |
661 | // We don't need to wait on the writes. |
662 | // Update iblock. | |
663 | } | |
664 | /* | |
665 | * The current page straddles initialized size. Zero | |
666 | * all non-uptodate buffers and set them uptodate (and | |
667 | * dirty?). Note, there aren't any non-uptodate buffers | |
668 | * if the page is uptodate. | |
669 | * FIXME: For an uptodate page, the buffers may need to | |
670 | * be written out because they were not initialized on | |
671 | * disk before. | |
672 | */ | |
673 | if (!PageUptodate(page)) { | |
674 | // TODO: | |
675 | // Zero any non-uptodate buffers up to i_size. | |
676 | // Set them uptodate and dirty. | |
677 | } | |
678 | // TODO: | |
679 | // Update initialized size in the attribute and in the | |
680 | // inode (up to i_size). | |
681 | // Update iblock. | |
682 | // FIXME: This is inefficient. Try to batch the two | |
683 | // size changes to happen in one go. | |
684 | ntfs_error(vol->sb, "Writing beyond initialized size " | |
685 | "is not supported yet. Sorry."); | |
686 | err = -EOPNOTSUPP; | |
687 | break; | |
688 | // Do NOT set_buffer_new() BUT DO clear buffer range | |
689 | // outside write request range. | |
690 | // set_buffer_uptodate() on complete buffers as well as | |
691 | // set_buffer_dirty(). | |
692 | } | |
693 | ||
694 | /* No need to map buffers that are already mapped. */ | |
695 | if (buffer_mapped(bh)) | |
696 | continue; | |
697 | ||
698 | /* Unmapped, dirty buffer. Need to map it. */ | |
699 | bh->b_bdev = vol->sb->s_bdev; | |
700 | ||
701 | /* Convert block into corresponding vcn and offset. */ | |
702 | vcn = (VCN)block << blocksize_bits; | |
703 | vcn_ofs = vcn & vol->cluster_size_mask; | |
704 | vcn >>= vol->cluster_size_bits; | |
705 | if (!rl) { | |
706 | lock_retry_remap: | |
707 | down_read(&ni->runlist.lock); | |
708 | rl = ni->runlist.rl; | |
709 | } | |
710 | if (likely(rl != NULL)) { | |
711 | /* Seek to element containing target vcn. */ | |
712 | while (rl->length && rl[1].vcn <= vcn) | |
713 | rl++; | |
714 | lcn = ntfs_rl_vcn_to_lcn(rl, vcn); | |
715 | } else | |
716 | lcn = LCN_RL_NOT_MAPPED; | |
717 | /* Successful remap. */ | |
718 | if (lcn >= 0) { | |
719 | /* Setup buffer head to point to correct block. */ | |
720 | bh->b_blocknr = ((lcn << vol->cluster_size_bits) + | |
721 | vcn_ofs) >> blocksize_bits; | |
722 | set_buffer_mapped(bh); | |
723 | continue; | |
724 | } | |
725 | /* It is a hole, need to instantiate it. */ | |
726 | if (lcn == LCN_HOLE) { | |
8dcdebaf AA |
727 | u8 *kaddr; |
728 | unsigned long *bpos, *bend; | |
729 | ||
730 | /* Check if the buffer is zero. */ | |
a3ac1414 | 731 | kaddr = kmap_atomic(page); |
8dcdebaf AA |
732 | bpos = (unsigned long *)(kaddr + bh_offset(bh)); |
733 | bend = (unsigned long *)((u8*)bpos + blocksize); | |
734 | do { | |
735 | if (unlikely(*bpos)) | |
736 | break; | |
737 | } while (likely(++bpos < bend)); | |
a3ac1414 | 738 | kunmap_atomic(kaddr); |
8dcdebaf AA |
739 | if (bpos == bend) { |
740 | /* | |
741 | * Buffer is zero and sparse, no need to write | |
742 | * it. | |
743 | */ | |
744 | bh->b_blocknr = -1; | |
745 | clear_buffer_dirty(bh); | |
746 | continue; | |
747 | } | |
1da177e4 LT |
748 | // TODO: Instantiate the hole. |
749 | // clear_buffer_new(bh); | |
e64855c6 | 750 | // clean_bdev_bh_alias(bh); |
1da177e4 LT |
751 | ntfs_error(vol->sb, "Writing into sparse regions is " |
752 | "not supported yet. Sorry."); | |
753 | err = -EOPNOTSUPP; | |
754 | break; | |
755 | } | |
756 | /* If first try and runlist unmapped, map and retry. */ | |
757 | if (!is_retry && lcn == LCN_RL_NOT_MAPPED) { | |
c49c3111 | 758 | is_retry = true; |
1da177e4 LT |
759 | /* |
760 | * Attempt to map runlist, dropping lock for | |
761 | * the duration. | |
762 | */ | |
763 | up_read(&ni->runlist.lock); | |
764 | err = ntfs_map_runlist(ni, vcn); | |
765 | if (likely(!err)) | |
766 | goto lock_retry_remap; | |
767 | rl = NULL; | |
9f993fe4 AA |
768 | } else if (!rl) |
769 | up_read(&ni->runlist.lock); | |
8273d5d4 AA |
770 | /* |
771 | * If buffer is outside the runlist, truncate has cut it out | |
772 | * of the runlist. Just clean and clear the buffer and set it | |
773 | * uptodate so it can get discarded by the VM. | |
774 | */ | |
775 | if (err == -ENOENT || lcn == LCN_ENOENT) { | |
8273d5d4 AA |
776 | bh->b_blocknr = -1; |
777 | clear_buffer_dirty(bh); | |
eebd2aa3 | 778 | zero_user(page, bh_offset(bh), blocksize); |
8273d5d4 AA |
779 | set_buffer_uptodate(bh); |
780 | err = 0; | |
781 | continue; | |
782 | } | |
1da177e4 | 783 | /* Failed to map the buffer, even after retrying. */ |
8273d5d4 AA |
784 | if (!err) |
785 | err = -EIO; | |
1da177e4 LT |
786 | bh->b_blocknr = -1; |
787 | ntfs_error(vol->sb, "Failed to write to inode 0x%lx, " | |
788 | "attribute type 0x%x, vcn 0x%llx, offset 0x%x " | |
789 | "because its location on disk could not be " | |
8273d5d4 | 790 | "determined%s (error code %i).", ni->mft_no, |
1da177e4 LT |
791 | ni->type, (unsigned long long)vcn, |
792 | vcn_ofs, is_retry ? " even after " | |
8273d5d4 | 793 | "retrying" : "", err); |
1da177e4 LT |
794 | break; |
795 | } while (block++, (bh = bh->b_this_page) != head); | |
796 | ||
797 | /* Release the lock if we took it. */ | |
798 | if (rl) | |
799 | up_read(&ni->runlist.lock); | |
800 | ||
801 | /* For the error case, need to reset bh to the beginning. */ | |
802 | bh = head; | |
803 | ||
54b02eb0 | 804 | /* Just an optimization, so ->readpage() is not called later. */ |
1da177e4 LT |
805 | if (unlikely(!PageUptodate(page))) { |
806 | int uptodate = 1; | |
807 | do { | |
808 | if (!buffer_uptodate(bh)) { | |
809 | uptodate = 0; | |
810 | bh = head; | |
811 | break; | |
812 | } | |
813 | } while ((bh = bh->b_this_page) != head); | |
814 | if (uptodate) | |
815 | SetPageUptodate(page); | |
816 | } | |
817 | ||
818 | /* Setup all mapped, dirty buffers for async write i/o. */ | |
819 | do { | |
1da177e4 LT |
820 | if (buffer_mapped(bh) && buffer_dirty(bh)) { |
821 | lock_buffer(bh); | |
822 | if (test_clear_buffer_dirty(bh)) { | |
823 | BUG_ON(!buffer_uptodate(bh)); | |
824 | mark_buffer_async_write(bh); | |
825 | } else | |
826 | unlock_buffer(bh); | |
827 | } else if (unlikely(err)) { | |
828 | /* | |
829 | * For the error case. The buffer may have been set | |
830 | * dirty during attachment to a dirty page. | |
831 | */ | |
832 | if (err != -ENOMEM) | |
833 | clear_buffer_dirty(bh); | |
834 | } | |
835 | } while ((bh = bh->b_this_page) != head); | |
836 | ||
837 | if (unlikely(err)) { | |
838 | // TODO: Remove the -EOPNOTSUPP check later on... | |
839 | if (unlikely(err == -EOPNOTSUPP)) | |
840 | err = 0; | |
841 | else if (err == -ENOMEM) { | |
842 | ntfs_warning(vol->sb, "Error allocating memory. " | |
843 | "Redirtying page so we try again " | |
844 | "later."); | |
845 | /* | |
846 | * Put the page back on mapping->dirty_pages, but | |
847 | * leave its buffer's dirty state as-is. | |
848 | */ | |
849 | redirty_page_for_writepage(wbc, page); | |
850 | err = 0; | |
851 | } else | |
852 | SetPageError(page); | |
853 | } | |
854 | ||
855 | BUG_ON(PageWriteback(page)); | |
856 | set_page_writeback(page); /* Keeps try_to_free_buffers() away. */ | |
1da177e4 | 857 | |
54b02eb0 | 858 | /* Submit the prepared buffers for i/o. */ |
c49c3111 | 859 | need_end_writeback = true; |
1da177e4 LT |
860 | do { |
861 | struct buffer_head *next = bh->b_this_page; | |
862 | if (buffer_async_write(bh)) { | |
2a222ca9 | 863 | submit_bh(REQ_OP_WRITE, 0, bh); |
c49c3111 | 864 | need_end_writeback = false; |
1da177e4 | 865 | } |
1da177e4 LT |
866 | bh = next; |
867 | } while (bh != head); | |
54b02eb0 | 868 | unlock_page(page); |
1da177e4 LT |
869 | |
870 | /* If no i/o was started, need to end_page_writeback(). */ | |
871 | if (unlikely(need_end_writeback)) | |
872 | end_page_writeback(page); | |
873 | ||
874 | ntfs_debug("Done."); | |
875 | return err; | |
876 | } | |
877 | ||
878 | /** | |
879 | * ntfs_write_mst_block - write a @page to the backing store | |
880 | * @page: page cache page to write out | |
881 | * @wbc: writeback control structure | |
882 | * | |
883 | * This function is for writing pages belonging to non-resident, mst protected | |
884 | * attributes to their backing store. The only supported attributes are index | |
885 | * allocation and $MFT/$DATA. Both directory inodes and index inodes are | |
886 | * supported for the index allocation case. | |
887 | * | |
888 | * The page must remain locked for the duration of the write because we apply | |
889 | * the mst fixups, write, and then undo the fixups, so if we were to unlock the | |
890 | * page before undoing the fixups, any other user of the page will see the | |
891 | * page contents as corrupt. | |
892 | * | |
893 | * We clear the page uptodate flag for the duration of the function to ensure | |
894 | * exclusion for the $MFT/$DATA case against someone mapping an mft record we | |
895 | * are about to apply the mst fixups to. | |
896 | * | |
897 | * Return 0 on success and -errno on error. | |
898 | * | |
899 | * Based on ntfs_write_block(), ntfs_mft_writepage(), and | |
900 | * write_mft_record_nolock(). | |
901 | */ | |
902 | static int ntfs_write_mst_block(struct page *page, | |
903 | struct writeback_control *wbc) | |
904 | { | |
905 | sector_t block, dblock, rec_block; | |
906 | struct inode *vi = page->mapping->host; | |
907 | ntfs_inode *ni = NTFS_I(vi); | |
908 | ntfs_volume *vol = ni->vol; | |
909 | u8 *kaddr; | |
1da177e4 | 910 | unsigned int rec_size = ni->itype.index.block_size; |
ac4ecf96 | 911 | ntfs_inode *locked_nis[PAGE_SIZE / NTFS_BLOCK_SIZE]; |
1da177e4 | 912 | struct buffer_head *bh, *head, *tbh, *rec_start_bh; |
d53ee322 | 913 | struct buffer_head *bhs[MAX_BUF_PER_PAGE]; |
1da177e4 | 914 | runlist_element *rl; |
d53ee322 AA |
915 | int i, nr_locked_nis, nr_recs, nr_bhs, max_bhs, bhs_per_rec, err, err2; |
916 | unsigned bh_size, rec_size_bits; | |
c49c3111 | 917 | bool sync, is_mft, page_is_dirty, rec_is_dirty; |
d53ee322 | 918 | unsigned char bh_size_bits; |
1da177e4 | 919 | |
ac4ecf96 KC |
920 | if (WARN_ON(rec_size < NTFS_BLOCK_SIZE)) |
921 | return -EINVAL; | |
922 | ||
1da177e4 LT |
923 | ntfs_debug("Entering for inode 0x%lx, attribute type 0x%x, page index " |
924 | "0x%lx.", vi->i_ino, ni->type, page->index); | |
925 | BUG_ON(!NInoNonResident(ni)); | |
926 | BUG_ON(!NInoMstProtected(ni)); | |
927 | is_mft = (S_ISREG(vi->i_mode) && !vi->i_ino); | |
928 | /* | |
929 | * NOTE: ntfs_write_mst_block() would be called for $MFTMirr if a page | |
930 | * in its page cache were to be marked dirty. However this should | |
931 | * never happen with the current driver and considering we do not | |
932 | * handle this case here we do want to BUG(), at least for now. | |
933 | */ | |
934 | BUG_ON(!(is_mft || S_ISDIR(vi->i_mode) || | |
935 | (NInoAttr(ni) && ni->type == AT_INDEX_ALLOCATION))); | |
78af34f0 AA |
936 | bh_size = vol->sb->s_blocksize; |
937 | bh_size_bits = vol->sb->s_blocksize_bits; | |
09cbfeaf | 938 | max_bhs = PAGE_SIZE / bh_size; |
1da177e4 | 939 | BUG_ON(!max_bhs); |
d53ee322 | 940 | BUG_ON(max_bhs > MAX_BUF_PER_PAGE); |
1da177e4 LT |
941 | |
942 | /* Were we called for sync purposes? */ | |
943 | sync = (wbc->sync_mode == WB_SYNC_ALL); | |
944 | ||
945 | /* Make sure we have mapped buffers. */ | |
1da177e4 LT |
946 | bh = head = page_buffers(page); |
947 | BUG_ON(!bh); | |
948 | ||
949 | rec_size_bits = ni->itype.index.block_size_bits; | |
09cbfeaf | 950 | BUG_ON(!(PAGE_SIZE >> rec_size_bits)); |
1da177e4 LT |
951 | bhs_per_rec = rec_size >> bh_size_bits; |
952 | BUG_ON(!bhs_per_rec); | |
953 | ||
954 | /* The first block in the page. */ | |
955 | rec_block = block = (sector_t)page->index << | |
09cbfeaf | 956 | (PAGE_SHIFT - bh_size_bits); |
1da177e4 LT |
957 | |
958 | /* The first out of bounds block for the data size. */ | |
07a4e2da | 959 | dblock = (i_size_read(vi) + bh_size - 1) >> bh_size_bits; |
1da177e4 LT |
960 | |
961 | rl = NULL; | |
962 | err = err2 = nr_bhs = nr_recs = nr_locked_nis = 0; | |
c49c3111 | 963 | page_is_dirty = rec_is_dirty = false; |
1da177e4 LT |
964 | rec_start_bh = NULL; |
965 | do { | |
c49c3111 | 966 | bool is_retry = false; |
1da177e4 LT |
967 | |
968 | if (likely(block < rec_block)) { | |
969 | if (unlikely(block >= dblock)) { | |
970 | clear_buffer_dirty(bh); | |
946929d8 | 971 | set_buffer_uptodate(bh); |
1da177e4 LT |
972 | continue; |
973 | } | |
974 | /* | |
975 | * This block is not the first one in the record. We | |
976 | * ignore the buffer's dirty state because we could | |
977 | * have raced with a parallel mark_ntfs_record_dirty(). | |
978 | */ | |
979 | if (!rec_is_dirty) | |
980 | continue; | |
981 | if (unlikely(err2)) { | |
982 | if (err2 != -ENOMEM) | |
983 | clear_buffer_dirty(bh); | |
984 | continue; | |
985 | } | |
986 | } else /* if (block == rec_block) */ { | |
987 | BUG_ON(block > rec_block); | |
988 | /* This block is the first one in the record. */ | |
989 | rec_block += bhs_per_rec; | |
990 | err2 = 0; | |
991 | if (unlikely(block >= dblock)) { | |
992 | clear_buffer_dirty(bh); | |
993 | continue; | |
994 | } | |
995 | if (!buffer_dirty(bh)) { | |
996 | /* Clean records are not written out. */ | |
c49c3111 | 997 | rec_is_dirty = false; |
1da177e4 LT |
998 | continue; |
999 | } | |
c49c3111 | 1000 | rec_is_dirty = true; |
1da177e4 LT |
1001 | rec_start_bh = bh; |
1002 | } | |
1003 | /* Need to map the buffer if it is not mapped already. */ | |
1004 | if (unlikely(!buffer_mapped(bh))) { | |
1005 | VCN vcn; | |
1006 | LCN lcn; | |
1007 | unsigned int vcn_ofs; | |
1008 | ||
481d0374 | 1009 | bh->b_bdev = vol->sb->s_bdev; |
1da177e4 LT |
1010 | /* Obtain the vcn and offset of the current block. */ |
1011 | vcn = (VCN)block << bh_size_bits; | |
1012 | vcn_ofs = vcn & vol->cluster_size_mask; | |
1013 | vcn >>= vol->cluster_size_bits; | |
1014 | if (!rl) { | |
1015 | lock_retry_remap: | |
1016 | down_read(&ni->runlist.lock); | |
1017 | rl = ni->runlist.rl; | |
1018 | } | |
1019 | if (likely(rl != NULL)) { | |
1020 | /* Seek to element containing target vcn. */ | |
1021 | while (rl->length && rl[1].vcn <= vcn) | |
1022 | rl++; | |
1023 | lcn = ntfs_rl_vcn_to_lcn(rl, vcn); | |
1024 | } else | |
1025 | lcn = LCN_RL_NOT_MAPPED; | |
1026 | /* Successful remap. */ | |
1027 | if (likely(lcn >= 0)) { | |
1028 | /* Setup buffer head to correct block. */ | |
1029 | bh->b_blocknr = ((lcn << | |
1030 | vol->cluster_size_bits) + | |
1031 | vcn_ofs) >> bh_size_bits; | |
1032 | set_buffer_mapped(bh); | |
1033 | } else { | |
1034 | /* | |
1035 | * Remap failed. Retry to map the runlist once | |
1036 | * unless we are working on $MFT which always | |
1037 | * has the whole of its runlist in memory. | |
1038 | */ | |
1039 | if (!is_mft && !is_retry && | |
1040 | lcn == LCN_RL_NOT_MAPPED) { | |
c49c3111 | 1041 | is_retry = true; |
1da177e4 LT |
1042 | /* |
1043 | * Attempt to map runlist, dropping | |
1044 | * lock for the duration. | |
1045 | */ | |
1046 | up_read(&ni->runlist.lock); | |
1047 | err2 = ntfs_map_runlist(ni, vcn); | |
1048 | if (likely(!err2)) | |
1049 | goto lock_retry_remap; | |
1050 | if (err2 == -ENOMEM) | |
c49c3111 | 1051 | page_is_dirty = true; |
1da177e4 | 1052 | lcn = err2; |
9f993fe4 | 1053 | } else { |
1da177e4 | 1054 | err2 = -EIO; |
9f993fe4 AA |
1055 | if (!rl) |
1056 | up_read(&ni->runlist.lock); | |
1057 | } | |
1da177e4 LT |
1058 | /* Hard error. Abort writing this record. */ |
1059 | if (!err || err == -ENOMEM) | |
1060 | err = err2; | |
1061 | bh->b_blocknr = -1; | |
1062 | ntfs_error(vol->sb, "Cannot write ntfs record " | |
1063 | "0x%llx (inode 0x%lx, " | |
1064 | "attribute type 0x%x) because " | |
1065 | "its location on disk could " | |
1066 | "not be determined (error " | |
8907547d RD |
1067 | "code %lli).", |
1068 | (long long)block << | |
1da177e4 LT |
1069 | bh_size_bits >> |
1070 | vol->mft_record_size_bits, | |
1071 | ni->mft_no, ni->type, | |
1072 | (long long)lcn); | |
1073 | /* | |
1074 | * If this is not the first buffer, remove the | |
1075 | * buffers in this record from the list of | |
1076 | * buffers to write and clear their dirty bit | |
1077 | * if not error -ENOMEM. | |
1078 | */ | |
1079 | if (rec_start_bh != bh) { | |
1080 | while (bhs[--nr_bhs] != rec_start_bh) | |
1081 | ; | |
1082 | if (err2 != -ENOMEM) { | |
1083 | do { | |
1084 | clear_buffer_dirty( | |
1085 | rec_start_bh); | |
1086 | } while ((rec_start_bh = | |
1087 | rec_start_bh-> | |
1088 | b_this_page) != | |
1089 | bh); | |
1090 | } | |
1091 | } | |
1092 | continue; | |
1093 | } | |
1094 | } | |
1095 | BUG_ON(!buffer_uptodate(bh)); | |
1096 | BUG_ON(nr_bhs >= max_bhs); | |
1097 | bhs[nr_bhs++] = bh; | |
1098 | } while (block++, (bh = bh->b_this_page) != head); | |
1099 | if (unlikely(rl)) | |
1100 | up_read(&ni->runlist.lock); | |
1101 | /* If there were no dirty buffers, we are done. */ | |
1102 | if (!nr_bhs) | |
1103 | goto done; | |
1104 | /* Map the page so we can access its contents. */ | |
1105 | kaddr = kmap(page); | |
1106 | /* Clear the page uptodate flag whilst the mst fixups are applied. */ | |
1107 | BUG_ON(!PageUptodate(page)); | |
1108 | ClearPageUptodate(page); | |
1109 | for (i = 0; i < nr_bhs; i++) { | |
1110 | unsigned int ofs; | |
1111 | ||
1112 | /* Skip buffers which are not at the beginning of records. */ | |
1113 | if (i % bhs_per_rec) | |
1114 | continue; | |
1115 | tbh = bhs[i]; | |
1116 | ofs = bh_offset(tbh); | |
1117 | if (is_mft) { | |
1118 | ntfs_inode *tni; | |
1119 | unsigned long mft_no; | |
1120 | ||
1121 | /* Get the mft record number. */ | |
09cbfeaf | 1122 | mft_no = (((s64)page->index << PAGE_SHIFT) + ofs) |
1da177e4 LT |
1123 | >> rec_size_bits; |
1124 | /* Check whether to write this mft record. */ | |
1125 | tni = NULL; | |
1126 | if (!ntfs_may_write_mft_record(vol, mft_no, | |
1127 | (MFT_RECORD*)(kaddr + ofs), &tni)) { | |
1128 | /* | |
1129 | * The record should not be written. This | |
1130 | * means we need to redirty the page before | |
1131 | * returning. | |
1132 | */ | |
c49c3111 | 1133 | page_is_dirty = true; |
1da177e4 LT |
1134 | /* |
1135 | * Remove the buffers in this mft record from | |
1136 | * the list of buffers to write. | |
1137 | */ | |
1138 | do { | |
1139 | bhs[i] = NULL; | |
1140 | } while (++i % bhs_per_rec); | |
1141 | continue; | |
1142 | } | |
1143 | /* | |
1144 | * The record should be written. If a locked ntfs | |
1145 | * inode was returned, add it to the array of locked | |
1146 | * ntfs inodes. | |
1147 | */ | |
1148 | if (tni) | |
1149 | locked_nis[nr_locked_nis++] = tni; | |
1150 | } | |
1151 | /* Apply the mst protection fixups. */ | |
1152 | err2 = pre_write_mst_fixup((NTFS_RECORD*)(kaddr + ofs), | |
1153 | rec_size); | |
1154 | if (unlikely(err2)) { | |
1155 | if (!err || err == -ENOMEM) | |
1156 | err = -EIO; | |
1157 | ntfs_error(vol->sb, "Failed to apply mst fixups " | |
1158 | "(inode 0x%lx, attribute type 0x%x, " | |
1159 | "page index 0x%lx, page offset 0x%x)!" | |
1160 | " Unmount and run chkdsk.", vi->i_ino, | |
1161 | ni->type, page->index, ofs); | |
1162 | /* | |
1163 | * Mark all the buffers in this record clean as we do | |
1164 | * not want to write corrupt data to disk. | |
1165 | */ | |
1166 | do { | |
1167 | clear_buffer_dirty(bhs[i]); | |
1168 | bhs[i] = NULL; | |
1169 | } while (++i % bhs_per_rec); | |
1170 | continue; | |
1171 | } | |
1172 | nr_recs++; | |
1173 | } | |
1174 | /* If no records are to be written out, we are done. */ | |
1175 | if (!nr_recs) | |
1176 | goto unm_done; | |
1177 | flush_dcache_page(page); | |
1178 | /* Lock buffers and start synchronous write i/o on them. */ | |
1179 | for (i = 0; i < nr_bhs; i++) { | |
1180 | tbh = bhs[i]; | |
1181 | if (!tbh) | |
1182 | continue; | |
ca5de404 | 1183 | if (!trylock_buffer(tbh)) |
1da177e4 LT |
1184 | BUG(); |
1185 | /* The buffer dirty state is now irrelevant, just clean it. */ | |
1186 | clear_buffer_dirty(tbh); | |
1187 | BUG_ON(!buffer_uptodate(tbh)); | |
1188 | BUG_ON(!buffer_mapped(tbh)); | |
1189 | get_bh(tbh); | |
1190 | tbh->b_end_io = end_buffer_write_sync; | |
2a222ca9 | 1191 | submit_bh(REQ_OP_WRITE, 0, tbh); |
1da177e4 LT |
1192 | } |
1193 | /* Synchronize the mft mirror now if not @sync. */ | |
1194 | if (is_mft && !sync) | |
1195 | goto do_mirror; | |
1196 | do_wait: | |
1197 | /* Wait on i/o completion of buffers. */ | |
1198 | for (i = 0; i < nr_bhs; i++) { | |
1199 | tbh = bhs[i]; | |
1200 | if (!tbh) | |
1201 | continue; | |
1202 | wait_on_buffer(tbh); | |
1203 | if (unlikely(!buffer_uptodate(tbh))) { | |
1204 | ntfs_error(vol->sb, "I/O error while writing ntfs " | |
1205 | "record buffer (inode 0x%lx, " | |
1206 | "attribute type 0x%x, page index " | |
1207 | "0x%lx, page offset 0x%lx)! Unmount " | |
1208 | "and run chkdsk.", vi->i_ino, ni->type, | |
1209 | page->index, bh_offset(tbh)); | |
1210 | if (!err || err == -ENOMEM) | |
1211 | err = -EIO; | |
1212 | /* | |
1213 | * Set the buffer uptodate so the page and buffer | |
1214 | * states do not become out of sync. | |
1215 | */ | |
1216 | set_buffer_uptodate(tbh); | |
1217 | } | |
1218 | } | |
1219 | /* If @sync, now synchronize the mft mirror. */ | |
1220 | if (is_mft && sync) { | |
1221 | do_mirror: | |
1222 | for (i = 0; i < nr_bhs; i++) { | |
1223 | unsigned long mft_no; | |
1224 | unsigned int ofs; | |
1225 | ||
1226 | /* | |
1227 | * Skip buffers which are not at the beginning of | |
1228 | * records. | |
1229 | */ | |
1230 | if (i % bhs_per_rec) | |
1231 | continue; | |
1232 | tbh = bhs[i]; | |
1233 | /* Skip removed buffers (and hence records). */ | |
1234 | if (!tbh) | |
1235 | continue; | |
1236 | ofs = bh_offset(tbh); | |
1237 | /* Get the mft record number. */ | |
09cbfeaf | 1238 | mft_no = (((s64)page->index << PAGE_SHIFT) + ofs) |
1da177e4 LT |
1239 | >> rec_size_bits; |
1240 | if (mft_no < vol->mftmirr_size) | |
1241 | ntfs_sync_mft_mirror(vol, mft_no, | |
1242 | (MFT_RECORD*)(kaddr + ofs), | |
1243 | sync); | |
1244 | } | |
1245 | if (!sync) | |
1246 | goto do_wait; | |
1247 | } | |
1248 | /* Remove the mst protection fixups again. */ | |
1249 | for (i = 0; i < nr_bhs; i++) { | |
1250 | if (!(i % bhs_per_rec)) { | |
1251 | tbh = bhs[i]; | |
1252 | if (!tbh) | |
1253 | continue; | |
1254 | post_write_mst_fixup((NTFS_RECORD*)(kaddr + | |
1255 | bh_offset(tbh))); | |
1256 | } | |
1257 | } | |
1258 | flush_dcache_page(page); | |
1259 | unm_done: | |
1260 | /* Unlock any locked inodes. */ | |
1261 | while (nr_locked_nis-- > 0) { | |
1262 | ntfs_inode *tni, *base_tni; | |
1263 | ||
1264 | tni = locked_nis[nr_locked_nis]; | |
1265 | /* Get the base inode. */ | |
4e5e529a | 1266 | mutex_lock(&tni->extent_lock); |
1da177e4 LT |
1267 | if (tni->nr_extents >= 0) |
1268 | base_tni = tni; | |
1269 | else { | |
1270 | base_tni = tni->ext.base_ntfs_ino; | |
1271 | BUG_ON(!base_tni); | |
1272 | } | |
4e5e529a | 1273 | mutex_unlock(&tni->extent_lock); |
1da177e4 LT |
1274 | ntfs_debug("Unlocking %s inode 0x%lx.", |
1275 | tni == base_tni ? "base" : "extent", | |
1276 | tni->mft_no); | |
4e5e529a | 1277 | mutex_unlock(&tni->mrec_lock); |
1da177e4 LT |
1278 | atomic_dec(&tni->count); |
1279 | iput(VFS_I(base_tni)); | |
1280 | } | |
1281 | SetPageUptodate(page); | |
1282 | kunmap(page); | |
1283 | done: | |
1284 | if (unlikely(err && err != -ENOMEM)) { | |
1285 | /* | |
1286 | * Set page error if there is only one ntfs record in the page. | |
1287 | * Otherwise we would loose per-record granularity. | |
1288 | */ | |
09cbfeaf | 1289 | if (ni->itype.index.block_size == PAGE_SIZE) |
1da177e4 LT |
1290 | SetPageError(page); |
1291 | NVolSetErrors(vol); | |
1292 | } | |
1293 | if (page_is_dirty) { | |
1294 | ntfs_debug("Page still contains one or more dirty ntfs " | |
1295 | "records. Redirtying the page starting at " | |
1296 | "record 0x%lx.", page->index << | |
09cbfeaf | 1297 | (PAGE_SHIFT - rec_size_bits)); |
1da177e4 LT |
1298 | redirty_page_for_writepage(wbc, page); |
1299 | unlock_page(page); | |
1300 | } else { | |
1301 | /* | |
1302 | * Keep the VM happy. This must be done otherwise the | |
1303 | * radix-tree tag PAGECACHE_TAG_DIRTY remains set even though | |
1304 | * the page is clean. | |
1305 | */ | |
1306 | BUG_ON(PageWriteback(page)); | |
1307 | set_page_writeback(page); | |
1308 | unlock_page(page); | |
1309 | end_page_writeback(page); | |
1310 | } | |
1311 | if (likely(!err)) | |
1312 | ntfs_debug("Done."); | |
1313 | return err; | |
1314 | } | |
1315 | ||
1316 | /** | |
1317 | * ntfs_writepage - write a @page to the backing store | |
1318 | * @page: page cache page to write out | |
1319 | * @wbc: writeback control structure | |
1320 | * | |
1321 | * This is called from the VM when it wants to have a dirty ntfs page cache | |
1322 | * page cleaned. The VM has already locked the page and marked it clean. | |
1323 | * | |
1324 | * For non-resident attributes, ntfs_writepage() writes the @page by calling | |
1325 | * the ntfs version of the generic block_write_full_page() function, | |
1326 | * ntfs_write_block(), which in turn if necessary creates and writes the | |
1327 | * buffers associated with the page asynchronously. | |
1328 | * | |
1329 | * For resident attributes, OTOH, ntfs_writepage() writes the @page by copying | |
1330 | * the data to the mft record (which at this stage is most likely in memory). | |
1331 | * The mft record is then marked dirty and written out asynchronously via the | |
1332 | * vfs inode dirty code path for the inode the mft record belongs to or via the | |
1333 | * vm page dirty code path for the page the mft record is in. | |
1334 | * | |
1335 | * Based on ntfs_readpage() and fs/buffer.c::block_write_full_page(). | |
1336 | * | |
1337 | * Return 0 on success and -errno on error. | |
1338 | */ | |
1339 | static int ntfs_writepage(struct page *page, struct writeback_control *wbc) | |
1340 | { | |
1341 | loff_t i_size; | |
149f0c52 AA |
1342 | struct inode *vi = page->mapping->host; |
1343 | ntfs_inode *base_ni = NULL, *ni = NTFS_I(vi); | |
bfab36e8 | 1344 | char *addr; |
149f0c52 AA |
1345 | ntfs_attr_search_ctx *ctx = NULL; |
1346 | MFT_RECORD *m = NULL; | |
1da177e4 LT |
1347 | u32 attr_len; |
1348 | int err; | |
1349 | ||
905685f6 | 1350 | retry_writepage: |
1da177e4 | 1351 | BUG_ON(!PageLocked(page)); |
1da177e4 | 1352 | i_size = i_size_read(vi); |
1da177e4 | 1353 | /* Is the page fully outside i_size? (truncate in progress) */ |
09cbfeaf KS |
1354 | if (unlikely(page->index >= (i_size + PAGE_SIZE - 1) >> |
1355 | PAGE_SHIFT)) { | |
1da177e4 LT |
1356 | /* |
1357 | * The page may have dirty, unmapped buffers. Make them | |
1358 | * freeable here, so the page does not leak. | |
1359 | */ | |
09cbfeaf | 1360 | block_invalidatepage(page, 0, PAGE_SIZE); |
1da177e4 LT |
1361 | unlock_page(page); |
1362 | ntfs_debug("Write outside i_size - truncated?"); | |
1363 | return 0; | |
1364 | } | |
bd45fdd2 AA |
1365 | /* |
1366 | * Only $DATA attributes can be encrypted and only unnamed $DATA | |
1367 | * attributes can be compressed. Index root can have the flags set but | |
1368 | * this means to create compressed/encrypted files, not that the | |
4e64c886 AA |
1369 | * attribute is compressed/encrypted. Note we need to check for |
1370 | * AT_INDEX_ALLOCATION since this is the type of both directory and | |
1371 | * index inodes. | |
bd45fdd2 | 1372 | */ |
4e64c886 | 1373 | if (ni->type != AT_INDEX_ALLOCATION) { |
bd45fdd2 AA |
1374 | /* If file is encrypted, deny access, just like NT4. */ |
1375 | if (NInoEncrypted(ni)) { | |
1376 | unlock_page(page); | |
1377 | BUG_ON(ni->type != AT_DATA); | |
7d0ffdb2 | 1378 | ntfs_debug("Denying write access to encrypted file."); |
bd45fdd2 AA |
1379 | return -EACCES; |
1380 | } | |
1381 | /* Compressed data streams are handled in compress.c. */ | |
1382 | if (NInoNonResident(ni) && NInoCompressed(ni)) { | |
1383 | BUG_ON(ni->type != AT_DATA); | |
1384 | BUG_ON(ni->name_len); | |
1385 | // TODO: Implement and replace this with | |
1386 | // return ntfs_write_compressed_block(page); | |
1387 | unlock_page(page); | |
1388 | ntfs_error(vi->i_sb, "Writing to compressed files is " | |
1389 | "not supported yet. Sorry."); | |
1390 | return -EOPNOTSUPP; | |
1391 | } | |
1392 | // TODO: Implement and remove this check. | |
1393 | if (NInoNonResident(ni) && NInoSparse(ni)) { | |
1394 | unlock_page(page); | |
1395 | ntfs_error(vi->i_sb, "Writing to sparse files is not " | |
1396 | "supported yet. Sorry."); | |
1397 | return -EOPNOTSUPP; | |
1398 | } | |
1399 | } | |
1da177e4 LT |
1400 | /* NInoNonResident() == NInoIndexAllocPresent() */ |
1401 | if (NInoNonResident(ni)) { | |
1da177e4 | 1402 | /* We have to zero every time due to mmap-at-end-of-file. */ |
09cbfeaf | 1403 | if (page->index >= (i_size >> PAGE_SHIFT)) { |
1da177e4 | 1404 | /* The page straddles i_size. */ |
09cbfeaf KS |
1405 | unsigned int ofs = i_size & ~PAGE_MASK; |
1406 | zero_user_segment(page, ofs, PAGE_SIZE); | |
1da177e4 LT |
1407 | } |
1408 | /* Handle mst protected attributes. */ | |
1409 | if (NInoMstProtected(ni)) | |
1410 | return ntfs_write_mst_block(page, wbc); | |
bd45fdd2 | 1411 | /* Normal, non-resident data stream. */ |
1da177e4 LT |
1412 | return ntfs_write_block(page, wbc); |
1413 | } | |
1414 | /* | |
bd45fdd2 AA |
1415 | * Attribute is resident, implying it is not compressed, encrypted, or |
1416 | * mst protected. This also means the attribute is smaller than an mft | |
1417 | * record and hence smaller than a page, so can simply return error on | |
1418 | * any pages with index above 0. Note the attribute can actually be | |
1419 | * marked compressed but if it is resident the actual data is not | |
1420 | * compressed so we are ok to ignore the compressed flag here. | |
1da177e4 LT |
1421 | */ |
1422 | BUG_ON(page_has_buffers(page)); | |
1423 | BUG_ON(!PageUptodate(page)); | |
1424 | if (unlikely(page->index > 0)) { | |
1425 | ntfs_error(vi->i_sb, "BUG()! page->index (0x%lx) > 0. " | |
1426 | "Aborting write.", page->index); | |
1427 | BUG_ON(PageWriteback(page)); | |
1428 | set_page_writeback(page); | |
1429 | unlock_page(page); | |
1430 | end_page_writeback(page); | |
1431 | return -EIO; | |
1432 | } | |
1433 | if (!NInoAttr(ni)) | |
1434 | base_ni = ni; | |
1435 | else | |
1436 | base_ni = ni->ext.base_ntfs_ino; | |
1437 | /* Map, pin, and lock the mft record. */ | |
1438 | m = map_mft_record(base_ni); | |
1439 | if (IS_ERR(m)) { | |
1440 | err = PTR_ERR(m); | |
1441 | m = NULL; | |
1442 | ctx = NULL; | |
1443 | goto err_out; | |
1444 | } | |
905685f6 AA |
1445 | /* |
1446 | * If a parallel write made the attribute non-resident, drop the mft | |
1447 | * record and retry the writepage. | |
1448 | */ | |
1449 | if (unlikely(NInoNonResident(ni))) { | |
1450 | unmap_mft_record(base_ni); | |
1451 | goto retry_writepage; | |
1452 | } | |
1da177e4 LT |
1453 | ctx = ntfs_attr_get_search_ctx(base_ni, m); |
1454 | if (unlikely(!ctx)) { | |
1455 | err = -ENOMEM; | |
1456 | goto err_out; | |
1457 | } | |
1458 | err = ntfs_attr_lookup(ni->type, ni->name, ni->name_len, | |
1459 | CASE_SENSITIVE, 0, NULL, 0, ctx); | |
1460 | if (unlikely(err)) | |
1461 | goto err_out; | |
1462 | /* | |
1463 | * Keep the VM happy. This must be done otherwise the radix-tree tag | |
1464 | * PAGECACHE_TAG_DIRTY remains set even though the page is clean. | |
1465 | */ | |
1466 | BUG_ON(PageWriteback(page)); | |
1467 | set_page_writeback(page); | |
1468 | unlock_page(page); | |
1da177e4 | 1469 | attr_len = le32_to_cpu(ctx->attr->data.resident.value_length); |
07a4e2da | 1470 | i_size = i_size_read(vi); |
1da177e4 | 1471 | if (unlikely(attr_len > i_size)) { |
f6098cf4 | 1472 | /* Race with shrinking truncate or a failed truncate. */ |
1da177e4 | 1473 | attr_len = i_size; |
f6098cf4 AA |
1474 | /* |
1475 | * If the truncate failed, fix it up now. If a concurrent | |
1476 | * truncate, we do its job, so it does not have to do anything. | |
1477 | */ | |
1478 | err = ntfs_resident_attr_value_resize(ctx->mrec, ctx->attr, | |
1479 | attr_len); | |
1480 | /* Shrinking cannot fail. */ | |
1481 | BUG_ON(err); | |
1da177e4 | 1482 | } |
a3ac1414 | 1483 | addr = kmap_atomic(page); |
1da177e4 LT |
1484 | /* Copy the data from the page to the mft record. */ |
1485 | memcpy((u8*)ctx->attr + | |
1486 | le16_to_cpu(ctx->attr->data.resident.value_offset), | |
bfab36e8 | 1487 | addr, attr_len); |
1da177e4 | 1488 | /* Zero out of bounds area in the page cache page. */ |
09cbfeaf | 1489 | memset(addr + attr_len, 0, PAGE_SIZE - attr_len); |
a3ac1414 | 1490 | kunmap_atomic(addr); |
f6098cf4 | 1491 | flush_dcache_page(page); |
7d0ffdb2 | 1492 | flush_dcache_mft_record_page(ctx->ntfs_ino); |
f6098cf4 | 1493 | /* We are done with the page. */ |
1da177e4 | 1494 | end_page_writeback(page); |
f6098cf4 | 1495 | /* Finally, mark the mft record dirty, so it gets written back. */ |
1da177e4 LT |
1496 | mark_mft_record_dirty(ctx->ntfs_ino); |
1497 | ntfs_attr_put_search_ctx(ctx); | |
1498 | unmap_mft_record(base_ni); | |
1499 | return 0; | |
1500 | err_out: | |
1501 | if (err == -ENOMEM) { | |
1502 | ntfs_warning(vi->i_sb, "Error allocating memory. Redirtying " | |
1503 | "page so we try again later."); | |
1504 | /* | |
1505 | * Put the page back on mapping->dirty_pages, but leave its | |
1506 | * buffers' dirty state as-is. | |
1507 | */ | |
1508 | redirty_page_for_writepage(wbc, page); | |
1509 | err = 0; | |
1510 | } else { | |
1511 | ntfs_error(vi->i_sb, "Resident attribute write failed with " | |
149f0c52 | 1512 | "error %i.", err); |
1da177e4 | 1513 | SetPageError(page); |
149f0c52 | 1514 | NVolSetErrors(ni->vol); |
1da177e4 LT |
1515 | } |
1516 | unlock_page(page); | |
1517 | if (ctx) | |
1518 | ntfs_attr_put_search_ctx(ctx); | |
1519 | if (m) | |
1520 | unmap_mft_record(base_ni); | |
1521 | return err; | |
1522 | } | |
1523 | ||
1da177e4 LT |
1524 | #endif /* NTFS_RW */ |
1525 | ||
3f7fc6f2 AA |
1526 | /** |
1527 | * ntfs_bmap - map logical file block to physical device block | |
1528 | * @mapping: address space mapping to which the block to be mapped belongs | |
1529 | * @block: logical block to map to its physical device block | |
1530 | * | |
1531 | * For regular, non-resident files (i.e. not compressed and not encrypted), map | |
1532 | * the logical @block belonging to the file described by the address space | |
1533 | * mapping @mapping to its physical device block. | |
1534 | * | |
1535 | * The size of the block is equal to the @s_blocksize field of the super block | |
1536 | * of the mounted file system which is guaranteed to be smaller than or equal | |
1537 | * to the cluster size thus the block is guaranteed to fit entirely inside the | |
1538 | * cluster which means we do not need to care how many contiguous bytes are | |
1539 | * available after the beginning of the block. | |
1540 | * | |
1541 | * Return the physical device block if the mapping succeeded or 0 if the block | |
1542 | * is sparse or there was an error. | |
1543 | * | |
1544 | * Note: This is a problem if someone tries to run bmap() on $Boot system file | |
1545 | * as that really is in block zero but there is nothing we can do. bmap() is | |
1546 | * just broken in that respect (just like it cannot distinguish sparse from | |
1547 | * not available or error). | |
1548 | */ | |
1549 | static sector_t ntfs_bmap(struct address_space *mapping, sector_t block) | |
1550 | { | |
1551 | s64 ofs, size; | |
1552 | loff_t i_size; | |
1553 | LCN lcn; | |
1554 | unsigned long blocksize, flags; | |
1555 | ntfs_inode *ni = NTFS_I(mapping->host); | |
1556 | ntfs_volume *vol = ni->vol; | |
1557 | unsigned delta; | |
1558 | unsigned char blocksize_bits, cluster_size_shift; | |
1559 | ||
1560 | ntfs_debug("Entering for mft_no 0x%lx, logical block 0x%llx.", | |
1561 | ni->mft_no, (unsigned long long)block); | |
1562 | if (ni->type != AT_DATA || !NInoNonResident(ni) || NInoEncrypted(ni)) { | |
1563 | ntfs_error(vol->sb, "BMAP does not make sense for %s " | |
1564 | "attributes, returning 0.", | |
1565 | (ni->type != AT_DATA) ? "non-data" : | |
1566 | (!NInoNonResident(ni) ? "resident" : | |
1567 | "encrypted")); | |
1568 | return 0; | |
1569 | } | |
1570 | /* None of these can happen. */ | |
1571 | BUG_ON(NInoCompressed(ni)); | |
1572 | BUG_ON(NInoMstProtected(ni)); | |
1573 | blocksize = vol->sb->s_blocksize; | |
1574 | blocksize_bits = vol->sb->s_blocksize_bits; | |
1575 | ofs = (s64)block << blocksize_bits; | |
1576 | read_lock_irqsave(&ni->size_lock, flags); | |
1577 | size = ni->initialized_size; | |
1578 | i_size = i_size_read(VFS_I(ni)); | |
1579 | read_unlock_irqrestore(&ni->size_lock, flags); | |
1580 | /* | |
1581 | * If the offset is outside the initialized size or the block straddles | |
1582 | * the initialized size then pretend it is a hole unless the | |
1583 | * initialized size equals the file size. | |
1584 | */ | |
1585 | if (unlikely(ofs >= size || (ofs + blocksize > size && size < i_size))) | |
1586 | goto hole; | |
1587 | cluster_size_shift = vol->cluster_size_bits; | |
1588 | down_read(&ni->runlist.lock); | |
1589 | lcn = ntfs_attr_vcn_to_lcn_nolock(ni, ofs >> cluster_size_shift, false); | |
1590 | up_read(&ni->runlist.lock); | |
1591 | if (unlikely(lcn < LCN_HOLE)) { | |
1592 | /* | |
1593 | * Step down to an integer to avoid gcc doing a long long | |
1594 | * comparision in the switch when we know @lcn is between | |
1595 | * LCN_HOLE and LCN_EIO (i.e. -1 to -5). | |
1596 | * | |
1597 | * Otherwise older gcc (at least on some architectures) will | |
1598 | * try to use __cmpdi2() which is of course not available in | |
1599 | * the kernel. | |
1600 | */ | |
1601 | switch ((int)lcn) { | |
1602 | case LCN_ENOENT: | |
1603 | /* | |
1604 | * If the offset is out of bounds then pretend it is a | |
1605 | * hole. | |
1606 | */ | |
1607 | goto hole; | |
1608 | case LCN_ENOMEM: | |
1609 | ntfs_error(vol->sb, "Not enough memory to complete " | |
1610 | "mapping for inode 0x%lx. " | |
1611 | "Returning 0.", ni->mft_no); | |
1612 | break; | |
1613 | default: | |
1614 | ntfs_error(vol->sb, "Failed to complete mapping for " | |
1615 | "inode 0x%lx. Run chkdsk. " | |
1616 | "Returning 0.", ni->mft_no); | |
1617 | break; | |
1618 | } | |
1619 | return 0; | |
1620 | } | |
1621 | if (lcn < 0) { | |
1622 | /* It is a hole. */ | |
1623 | hole: | |
1624 | ntfs_debug("Done (returning hole)."); | |
1625 | return 0; | |
1626 | } | |
1627 | /* | |
1628 | * The block is really allocated and fullfils all our criteria. | |
1629 | * Convert the cluster to units of block size and return the result. | |
1630 | */ | |
1631 | delta = ofs & vol->cluster_size_mask; | |
1632 | if (unlikely(sizeof(block) < sizeof(lcn))) { | |
1633 | block = lcn = ((lcn << cluster_size_shift) + delta) >> | |
1634 | blocksize_bits; | |
1635 | /* If the block number was truncated return 0. */ | |
1636 | if (unlikely(block != lcn)) { | |
1637 | ntfs_error(vol->sb, "Physical block 0x%llx is too " | |
1638 | "large to be returned, returning 0.", | |
1639 | (long long)lcn); | |
1640 | return 0; | |
1641 | } | |
1642 | } else | |
1643 | block = ((lcn << cluster_size_shift) + delta) >> | |
1644 | blocksize_bits; | |
1645 | ntfs_debug("Done (returning block 0x%llx).", (unsigned long long)lcn); | |
1646 | return block; | |
1647 | } | |
1648 | ||
1da177e4 | 1649 | /** |
ce1bafa0 AA |
1650 | * ntfs_normal_aops - address space operations for normal inodes and attributes |
1651 | * | |
1652 | * Note these are not used for compressed or mst protected inodes and | |
1653 | * attributes. | |
1da177e4 | 1654 | */ |
ce1bafa0 AA |
1655 | const struct address_space_operations ntfs_normal_aops = { |
1656 | .readpage = ntfs_readpage, | |
1da177e4 | 1657 | #ifdef NTFS_RW |
ce1bafa0 AA |
1658 | .writepage = ntfs_writepage, |
1659 | .set_page_dirty = __set_page_dirty_buffers, | |
1660 | #endif /* NTFS_RW */ | |
3f7fc6f2 | 1661 | .bmap = ntfs_bmap, |
ce1bafa0 AA |
1662 | .migratepage = buffer_migrate_page, |
1663 | .is_partially_uptodate = block_is_partially_uptodate, | |
1664 | .error_remove_page = generic_error_remove_page, | |
1665 | }; | |
1666 | ||
1667 | /** | |
1668 | * ntfs_compressed_aops - address space operations for compressed inodes | |
1669 | */ | |
1670 | const struct address_space_operations ntfs_compressed_aops = { | |
1671 | .readpage = ntfs_readpage, | |
1672 | #ifdef NTFS_RW | |
1673 | .writepage = ntfs_writepage, | |
1674 | .set_page_dirty = __set_page_dirty_buffers, | |
1da177e4 | 1675 | #endif /* NTFS_RW */ |
ce1bafa0 AA |
1676 | .migratepage = buffer_migrate_page, |
1677 | .is_partially_uptodate = block_is_partially_uptodate, | |
aa261f54 | 1678 | .error_remove_page = generic_error_remove_page, |
1da177e4 LT |
1679 | }; |
1680 | ||
1681 | /** | |
1682 | * ntfs_mst_aops - general address space operations for mst protecteed inodes | |
1683 | * and attributes | |
1684 | */ | |
f5e54d6e | 1685 | const struct address_space_operations ntfs_mst_aops = { |
1da177e4 | 1686 | .readpage = ntfs_readpage, /* Fill page with data. */ |
1da177e4 LT |
1687 | #ifdef NTFS_RW |
1688 | .writepage = ntfs_writepage, /* Write dirty page to disk. */ | |
1689 | .set_page_dirty = __set_page_dirty_nobuffers, /* Set the page dirty | |
1690 | without touching the buffers | |
1691 | belonging to the page. */ | |
1692 | #endif /* NTFS_RW */ | |
ce1bafa0 AA |
1693 | .migratepage = buffer_migrate_page, |
1694 | .is_partially_uptodate = block_is_partially_uptodate, | |
aa261f54 | 1695 | .error_remove_page = generic_error_remove_page, |
1da177e4 LT |
1696 | }; |
1697 | ||
1698 | #ifdef NTFS_RW | |
1699 | ||
1700 | /** | |
1701 | * mark_ntfs_record_dirty - mark an ntfs record dirty | |
1702 | * @page: page containing the ntfs record to mark dirty | |
1703 | * @ofs: byte offset within @page at which the ntfs record begins | |
1704 | * | |
1705 | * Set the buffers and the page in which the ntfs record is located dirty. | |
1706 | * | |
1707 | * The latter also marks the vfs inode the ntfs record belongs to dirty | |
1708 | * (I_DIRTY_PAGES only). | |
1709 | * | |
1710 | * If the page does not have buffers, we create them and set them uptodate. | |
1711 | * The page may not be locked which is why we need to handle the buffers under | |
1712 | * the mapping->private_lock. Once the buffers are marked dirty we no longer | |
1713 | * need the lock since try_to_free_buffers() does not free dirty buffers. | |
1714 | */ | |
1715 | void mark_ntfs_record_dirty(struct page *page, const unsigned int ofs) { | |
1716 | struct address_space *mapping = page->mapping; | |
1717 | ntfs_inode *ni = NTFS_I(mapping->host); | |
1718 | struct buffer_head *bh, *head, *buffers_to_free = NULL; | |
1719 | unsigned int end, bh_size, bh_ofs; | |
1720 | ||
1721 | BUG_ON(!PageUptodate(page)); | |
1722 | end = ofs + ni->itype.index.block_size; | |
78af34f0 | 1723 | bh_size = VFS_I(ni)->i_sb->s_blocksize; |
1da177e4 LT |
1724 | spin_lock(&mapping->private_lock); |
1725 | if (unlikely(!page_has_buffers(page))) { | |
1726 | spin_unlock(&mapping->private_lock); | |
640ab98f | 1727 | bh = head = alloc_page_buffers(page, bh_size, true); |
1da177e4 LT |
1728 | spin_lock(&mapping->private_lock); |
1729 | if (likely(!page_has_buffers(page))) { | |
1730 | struct buffer_head *tail; | |
1731 | ||
1732 | do { | |
1733 | set_buffer_uptodate(bh); | |
1734 | tail = bh; | |
1735 | bh = bh->b_this_page; | |
1736 | } while (bh); | |
1737 | tail->b_this_page = head; | |
1738 | attach_page_buffers(page, head); | |
1739 | } else | |
1740 | buffers_to_free = bh; | |
1741 | } | |
1742 | bh = head = page_buffers(page); | |
a01ac532 | 1743 | BUG_ON(!bh); |
1da177e4 LT |
1744 | do { |
1745 | bh_ofs = bh_offset(bh); | |
1746 | if (bh_ofs + bh_size <= ofs) | |
1747 | continue; | |
1748 | if (unlikely(bh_ofs >= end)) | |
1749 | break; | |
1750 | set_buffer_dirty(bh); | |
1751 | } while ((bh = bh->b_this_page) != head); | |
1752 | spin_unlock(&mapping->private_lock); | |
1753 | __set_page_dirty_nobuffers(page); | |
1754 | if (unlikely(buffers_to_free)) { | |
1755 | do { | |
1756 | bh = buffers_to_free->b_this_page; | |
1757 | free_buffer_head(buffers_to_free); | |
1758 | buffers_to_free = bh; | |
1759 | } while (buffers_to_free); | |
1760 | } | |
1761 | } | |
1762 | ||
1763 | #endif /* NTFS_RW */ |