Commit | Line | Data |
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1da177e4 LT |
1 | /** |
2 | * aops.c - NTFS kernel address space operations and page cache handling. | |
3 | * Part of the Linux-NTFS project. | |
4 | * | |
b6ad6c52 | 5 | * Copyright (c) 2001-2005 Anton Altaparmakov |
1da177e4 LT |
6 | * 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> | |
25 | #include <linux/mm.h> | |
26 | #include <linux/pagemap.h> | |
27 | #include <linux/swap.h> | |
28 | #include <linux/buffer_head.h> | |
29 | #include <linux/writeback.h> | |
b4012a98 | 30 | #include <linux/bit_spinlock.h> |
1da177e4 LT |
31 | |
32 | #include "aops.h" | |
33 | #include "attrib.h" | |
34 | #include "debug.h" | |
35 | #include "inode.h" | |
36 | #include "mft.h" | |
37 | #include "runlist.h" | |
38 | #include "types.h" | |
39 | #include "ntfs.h" | |
40 | ||
41 | /** | |
42 | * ntfs_end_buffer_async_read - async io completion for reading attributes | |
43 | * @bh: buffer head on which io is completed | |
44 | * @uptodate: whether @bh is now uptodate or not | |
45 | * | |
46 | * Asynchronous I/O completion handler for reading pages belonging to the | |
47 | * attribute address space of an inode. The inodes can either be files or | |
48 | * directories or they can be fake inodes describing some attribute. | |
49 | * | |
50 | * If NInoMstProtected(), perform the post read mst fixups when all IO on the | |
51 | * page has been completed and mark the page uptodate or set the error bit on | |
52 | * the page. To determine the size of the records that need fixing up, we | |
53 | * cheat a little bit by setting the index_block_size in ntfs_inode to the ntfs | |
54 | * record size, and index_block_size_bits, to the log(base 2) of the ntfs | |
55 | * record size. | |
56 | */ | |
57 | static void ntfs_end_buffer_async_read(struct buffer_head *bh, int uptodate) | |
58 | { | |
1da177e4 | 59 | unsigned long flags; |
e604635c | 60 | struct buffer_head *first, *tmp; |
1da177e4 LT |
61 | struct page *page; |
62 | ntfs_inode *ni; | |
63 | int page_uptodate = 1; | |
64 | ||
65 | page = bh->b_page; | |
66 | ni = NTFS_I(page->mapping->host); | |
67 | ||
68 | if (likely(uptodate)) { | |
07a4e2da | 69 | s64 file_ofs, initialized_size; |
1da177e4 LT |
70 | |
71 | set_buffer_uptodate(bh); | |
72 | ||
73 | file_ofs = ((s64)page->index << PAGE_CACHE_SHIFT) + | |
74 | bh_offset(bh); | |
07a4e2da AA |
75 | read_lock_irqsave(&ni->size_lock, flags); |
76 | initialized_size = ni->initialized_size; | |
77 | read_unlock_irqrestore(&ni->size_lock, flags); | |
1da177e4 | 78 | /* Check for the current buffer head overflowing. */ |
07a4e2da | 79 | if (file_ofs + bh->b_size > initialized_size) { |
1da177e4 LT |
80 | char *addr; |
81 | int ofs = 0; | |
82 | ||
07a4e2da AA |
83 | if (file_ofs < initialized_size) |
84 | ofs = initialized_size - file_ofs; | |
1da177e4 LT |
85 | addr = kmap_atomic(page, KM_BIO_SRC_IRQ); |
86 | memset(addr + bh_offset(bh) + ofs, 0, bh->b_size - ofs); | |
87 | flush_dcache_page(page); | |
88 | kunmap_atomic(addr, KM_BIO_SRC_IRQ); | |
89 | } | |
90 | } else { | |
91 | clear_buffer_uptodate(bh); | |
e604635c | 92 | SetPageError(page); |
1da177e4 LT |
93 | ntfs_error(ni->vol->sb, "Buffer I/O error, logical block %llu.", |
94 | (unsigned long long)bh->b_blocknr); | |
1da177e4 | 95 | } |
e604635c AA |
96 | first = page_buffers(page); |
97 | local_irq_save(flags); | |
98 | bit_spin_lock(BH_Uptodate_Lock, &first->b_state); | |
1da177e4 LT |
99 | clear_buffer_async_read(bh); |
100 | unlock_buffer(bh); | |
101 | tmp = bh; | |
102 | do { | |
103 | if (!buffer_uptodate(tmp)) | |
104 | page_uptodate = 0; | |
105 | if (buffer_async_read(tmp)) { | |
106 | if (likely(buffer_locked(tmp))) | |
107 | goto still_busy; | |
108 | /* Async buffers must be locked. */ | |
109 | BUG(); | |
110 | } | |
111 | tmp = tmp->b_this_page; | |
112 | } while (tmp != bh); | |
e604635c AA |
113 | bit_spin_unlock(BH_Uptodate_Lock, &first->b_state); |
114 | local_irq_restore(flags); | |
1da177e4 LT |
115 | /* |
116 | * If none of the buffers had errors then we can set the page uptodate, | |
117 | * but we first have to perform the post read mst fixups, if the | |
118 | * attribute is mst protected, i.e. if NInoMstProteced(ni) is true. | |
119 | * Note we ignore fixup errors as those are detected when | |
120 | * map_mft_record() is called which gives us per record granularity | |
121 | * rather than per page granularity. | |
122 | */ | |
123 | if (!NInoMstProtected(ni)) { | |
124 | if (likely(page_uptodate && !PageError(page))) | |
125 | SetPageUptodate(page); | |
126 | } else { | |
127 | char *addr; | |
128 | unsigned int i, recs; | |
129 | u32 rec_size; | |
130 | ||
131 | rec_size = ni->itype.index.block_size; | |
132 | recs = PAGE_CACHE_SIZE / rec_size; | |
133 | /* Should have been verified before we got here... */ | |
134 | BUG_ON(!recs); | |
135 | addr = kmap_atomic(page, KM_BIO_SRC_IRQ); | |
136 | for (i = 0; i < recs; i++) | |
137 | post_read_mst_fixup((NTFS_RECORD*)(addr + | |
138 | i * rec_size), rec_size); | |
139 | flush_dcache_page(page); | |
140 | kunmap_atomic(addr, KM_BIO_SRC_IRQ); | |
b6ad6c52 | 141 | if (likely(page_uptodate && !PageError(page))) |
1da177e4 LT |
142 | SetPageUptodate(page); |
143 | } | |
144 | unlock_page(page); | |
145 | return; | |
146 | still_busy: | |
e604635c AA |
147 | bit_spin_unlock(BH_Uptodate_Lock, &first->b_state); |
148 | local_irq_restore(flags); | |
1da177e4 LT |
149 | return; |
150 | } | |
151 | ||
152 | /** | |
153 | * ntfs_read_block - fill a @page of an address space with data | |
154 | * @page: page cache page to fill with data | |
155 | * | |
156 | * Fill the page @page of the address space belonging to the @page->host inode. | |
157 | * We read each buffer asynchronously and when all buffers are read in, our io | |
158 | * completion handler ntfs_end_buffer_read_async(), if required, automatically | |
159 | * applies the mst fixups to the page before finally marking it uptodate and | |
160 | * unlocking it. | |
161 | * | |
162 | * We only enforce allocated_size limit because i_size is checked for in | |
163 | * generic_file_read(). | |
164 | * | |
165 | * Return 0 on success and -errno on error. | |
166 | * | |
167 | * Contains an adapted version of fs/buffer.c::block_read_full_page(). | |
168 | */ | |
169 | static int ntfs_read_block(struct page *page) | |
170 | { | |
171 | VCN vcn; | |
172 | LCN lcn; | |
173 | ntfs_inode *ni; | |
174 | ntfs_volume *vol; | |
175 | runlist_element *rl; | |
176 | struct buffer_head *bh, *head, *arr[MAX_BUF_PER_PAGE]; | |
177 | sector_t iblock, lblock, zblock; | |
07a4e2da | 178 | unsigned long flags; |
1da177e4 LT |
179 | unsigned int blocksize, vcn_ofs; |
180 | int i, nr; | |
181 | unsigned char blocksize_bits; | |
182 | ||
183 | ni = NTFS_I(page->mapping->host); | |
184 | vol = ni->vol; | |
185 | ||
186 | /* $MFT/$DATA must have its complete runlist in memory at all times. */ | |
187 | BUG_ON(!ni->runlist.rl && !ni->mft_no && !NInoAttr(ni)); | |
188 | ||
189 | blocksize_bits = VFS_I(ni)->i_blkbits; | |
190 | blocksize = 1 << blocksize_bits; | |
191 | ||
a01ac532 | 192 | if (!page_has_buffers(page)) { |
1da177e4 | 193 | create_empty_buffers(page, blocksize, 0); |
a01ac532 AA |
194 | if (unlikely(!page_has_buffers(page))) { |
195 | unlock_page(page); | |
196 | return -ENOMEM; | |
197 | } | |
1da177e4 | 198 | } |
a01ac532 AA |
199 | bh = head = page_buffers(page); |
200 | BUG_ON(!bh); | |
1da177e4 LT |
201 | |
202 | iblock = (s64)page->index << (PAGE_CACHE_SHIFT - blocksize_bits); | |
07a4e2da | 203 | read_lock_irqsave(&ni->size_lock, flags); |
1da177e4 LT |
204 | lblock = (ni->allocated_size + blocksize - 1) >> blocksize_bits; |
205 | zblock = (ni->initialized_size + blocksize - 1) >> blocksize_bits; | |
07a4e2da | 206 | read_unlock_irqrestore(&ni->size_lock, flags); |
1da177e4 LT |
207 | |
208 | /* Loop through all the buffers in the page. */ | |
209 | rl = NULL; | |
210 | nr = i = 0; | |
211 | do { | |
212 | u8 *kaddr; | |
8273d5d4 | 213 | int err; |
1da177e4 LT |
214 | |
215 | if (unlikely(buffer_uptodate(bh))) | |
216 | continue; | |
217 | if (unlikely(buffer_mapped(bh))) { | |
218 | arr[nr++] = bh; | |
219 | continue; | |
220 | } | |
8273d5d4 | 221 | err = 0; |
1da177e4 LT |
222 | bh->b_bdev = vol->sb->s_bdev; |
223 | /* Is the block within the allowed limits? */ | |
224 | if (iblock < lblock) { | |
225 | BOOL is_retry = FALSE; | |
226 | ||
227 | /* Convert iblock into corresponding vcn and offset. */ | |
228 | vcn = (VCN)iblock << blocksize_bits >> | |
229 | vol->cluster_size_bits; | |
230 | vcn_ofs = ((VCN)iblock << blocksize_bits) & | |
231 | vol->cluster_size_mask; | |
232 | if (!rl) { | |
233 | lock_retry_remap: | |
234 | down_read(&ni->runlist.lock); | |
235 | rl = ni->runlist.rl; | |
236 | } | |
237 | if (likely(rl != NULL)) { | |
238 | /* Seek to element containing target vcn. */ | |
239 | while (rl->length && rl[1].vcn <= vcn) | |
240 | rl++; | |
241 | lcn = ntfs_rl_vcn_to_lcn(rl, vcn); | |
242 | } else | |
243 | lcn = LCN_RL_NOT_MAPPED; | |
244 | /* Successful remap. */ | |
245 | if (lcn >= 0) { | |
246 | /* Setup buffer head to correct block. */ | |
247 | bh->b_blocknr = ((lcn << vol->cluster_size_bits) | |
248 | + vcn_ofs) >> blocksize_bits; | |
249 | set_buffer_mapped(bh); | |
250 | /* Only read initialized data blocks. */ | |
251 | if (iblock < zblock) { | |
252 | arr[nr++] = bh; | |
253 | continue; | |
254 | } | |
255 | /* Fully non-initialized data block, zero it. */ | |
256 | goto handle_zblock; | |
257 | } | |
258 | /* It is a hole, need to zero it. */ | |
259 | if (lcn == LCN_HOLE) | |
260 | goto handle_hole; | |
261 | /* If first try and runlist unmapped, map and retry. */ | |
262 | if (!is_retry && lcn == LCN_RL_NOT_MAPPED) { | |
1da177e4 LT |
263 | is_retry = TRUE; |
264 | /* | |
265 | * Attempt to map runlist, dropping lock for | |
266 | * the duration. | |
267 | */ | |
268 | up_read(&ni->runlist.lock); | |
269 | err = ntfs_map_runlist(ni, vcn); | |
270 | if (likely(!err)) | |
271 | goto lock_retry_remap; | |
272 | rl = NULL; | |
9f993fe4 AA |
273 | } else if (!rl) |
274 | up_read(&ni->runlist.lock); | |
8273d5d4 AA |
275 | /* |
276 | * If buffer is outside the runlist, treat it as a | |
277 | * hole. This can happen due to concurrent truncate | |
278 | * for example. | |
279 | */ | |
280 | if (err == -ENOENT || lcn == LCN_ENOENT) { | |
281 | err = 0; | |
282 | goto handle_hole; | |
283 | } | |
1da177e4 | 284 | /* Hard error, zero out region. */ |
8273d5d4 AA |
285 | if (!err) |
286 | err = -EIO; | |
1da177e4 LT |
287 | bh->b_blocknr = -1; |
288 | SetPageError(page); | |
289 | ntfs_error(vol->sb, "Failed to read from inode 0x%lx, " | |
290 | "attribute type 0x%x, vcn 0x%llx, " | |
291 | "offset 0x%x because its location on " | |
292 | "disk could not be determined%s " | |
8273d5d4 | 293 | "(error code %i).", ni->mft_no, |
1da177e4 LT |
294 | ni->type, (unsigned long long)vcn, |
295 | vcn_ofs, is_retry ? " even after " | |
8273d5d4 | 296 | "retrying" : "", err); |
1da177e4 LT |
297 | } |
298 | /* | |
299 | * Either iblock was outside lblock limits or | |
300 | * ntfs_rl_vcn_to_lcn() returned error. Just zero that portion | |
301 | * of the page and set the buffer uptodate. | |
302 | */ | |
303 | handle_hole: | |
304 | bh->b_blocknr = -1UL; | |
305 | clear_buffer_mapped(bh); | |
306 | handle_zblock: | |
307 | kaddr = kmap_atomic(page, KM_USER0); | |
308 | memset(kaddr + i * blocksize, 0, blocksize); | |
1da177e4 | 309 | kunmap_atomic(kaddr, KM_USER0); |
8273d5d4 AA |
310 | flush_dcache_page(page); |
311 | if (likely(!err)) | |
312 | set_buffer_uptodate(bh); | |
1da177e4 LT |
313 | } while (i++, iblock++, (bh = bh->b_this_page) != head); |
314 | ||
315 | /* Release the lock if we took it. */ | |
316 | if (rl) | |
317 | up_read(&ni->runlist.lock); | |
318 | ||
319 | /* Check we have at least one buffer ready for i/o. */ | |
320 | if (nr) { | |
321 | struct buffer_head *tbh; | |
322 | ||
323 | /* Lock the buffers. */ | |
324 | for (i = 0; i < nr; i++) { | |
325 | tbh = arr[i]; | |
326 | lock_buffer(tbh); | |
327 | tbh->b_end_io = ntfs_end_buffer_async_read; | |
328 | set_buffer_async_read(tbh); | |
329 | } | |
330 | /* Finally, start i/o on the buffers. */ | |
331 | for (i = 0; i < nr; i++) { | |
332 | tbh = arr[i]; | |
333 | if (likely(!buffer_uptodate(tbh))) | |
334 | submit_bh(READ, tbh); | |
335 | else | |
336 | ntfs_end_buffer_async_read(tbh, 1); | |
337 | } | |
338 | return 0; | |
339 | } | |
340 | /* No i/o was scheduled on any of the buffers. */ | |
341 | if (likely(!PageError(page))) | |
342 | SetPageUptodate(page); | |
343 | else /* Signal synchronous i/o error. */ | |
344 | nr = -EIO; | |
345 | unlock_page(page); | |
346 | return nr; | |
347 | } | |
348 | ||
349 | /** | |
350 | * ntfs_readpage - fill a @page of a @file with data from the device | |
351 | * @file: open file to which the page @page belongs or NULL | |
352 | * @page: page cache page to fill with data | |
353 | * | |
354 | * For non-resident attributes, ntfs_readpage() fills the @page of the open | |
355 | * file @file by calling the ntfs version of the generic block_read_full_page() | |
356 | * function, ntfs_read_block(), which in turn creates and reads in the buffers | |
357 | * associated with the page asynchronously. | |
358 | * | |
359 | * For resident attributes, OTOH, ntfs_readpage() fills @page by copying the | |
360 | * data from the mft record (which at this stage is most likely in memory) and | |
361 | * fills the remainder with zeroes. Thus, in this case, I/O is synchronous, as | |
362 | * even if the mft record is not cached at this point in time, we need to wait | |
363 | * for it to be read in before we can do the copy. | |
364 | * | |
365 | * Return 0 on success and -errno on error. | |
366 | */ | |
367 | static int ntfs_readpage(struct file *file, struct page *page) | |
368 | { | |
1da177e4 LT |
369 | ntfs_inode *ni, *base_ni; |
370 | u8 *kaddr; | |
371 | ntfs_attr_search_ctx *ctx; | |
372 | MFT_RECORD *mrec; | |
b6ad6c52 | 373 | unsigned long flags; |
1da177e4 LT |
374 | u32 attr_len; |
375 | int err = 0; | |
376 | ||
905685f6 | 377 | retry_readpage: |
1da177e4 LT |
378 | BUG_ON(!PageLocked(page)); |
379 | /* | |
380 | * This can potentially happen because we clear PageUptodate() during | |
381 | * ntfs_writepage() of MstProtected() attributes. | |
382 | */ | |
383 | if (PageUptodate(page)) { | |
384 | unlock_page(page); | |
385 | return 0; | |
386 | } | |
387 | ni = NTFS_I(page->mapping->host); | |
311120ec AA |
388 | /* |
389 | * Only $DATA attributes can be encrypted and only unnamed $DATA | |
390 | * attributes can be compressed. Index root can have the flags set but | |
391 | * this means to create compressed/encrypted files, not that the | |
4e64c886 AA |
392 | * attribute is compressed/encrypted. Note we need to check for |
393 | * AT_INDEX_ALLOCATION since this is the type of both directory and | |
394 | * index inodes. | |
311120ec | 395 | */ |
4e64c886 | 396 | if (ni->type != AT_INDEX_ALLOCATION) { |
311120ec AA |
397 | /* If attribute is encrypted, deny access, just like NT4. */ |
398 | if (NInoEncrypted(ni)) { | |
399 | BUG_ON(ni->type != AT_DATA); | |
400 | err = -EACCES; | |
401 | goto err_out; | |
402 | } | |
403 | /* Compressed data streams are handled in compress.c. */ | |
404 | if (NInoNonResident(ni) && NInoCompressed(ni)) { | |
405 | BUG_ON(ni->type != AT_DATA); | |
406 | BUG_ON(ni->name_len); | |
407 | return ntfs_read_compressed_block(page); | |
408 | } | |
409 | } | |
1da177e4 LT |
410 | /* NInoNonResident() == NInoIndexAllocPresent() */ |
411 | if (NInoNonResident(ni)) { | |
311120ec | 412 | /* Normal, non-resident data stream. */ |
1da177e4 LT |
413 | return ntfs_read_block(page); |
414 | } | |
415 | /* | |
416 | * Attribute is resident, implying it is not compressed or encrypted. | |
417 | * This also means the attribute is smaller than an mft record and | |
418 | * hence smaller than a page, so can simply zero out any pages with | |
311120ec AA |
419 | * index above 0. Note the attribute can actually be marked compressed |
420 | * but if it is resident the actual data is not compressed so we are | |
421 | * ok to ignore the compressed flag here. | |
1da177e4 | 422 | */ |
b6ad6c52 | 423 | if (unlikely(page->index > 0)) { |
1da177e4 LT |
424 | kaddr = kmap_atomic(page, KM_USER0); |
425 | memset(kaddr, 0, PAGE_CACHE_SIZE); | |
426 | flush_dcache_page(page); | |
427 | kunmap_atomic(kaddr, KM_USER0); | |
428 | goto done; | |
429 | } | |
430 | if (!NInoAttr(ni)) | |
431 | base_ni = ni; | |
432 | else | |
433 | base_ni = ni->ext.base_ntfs_ino; | |
434 | /* Map, pin, and lock the mft record. */ | |
435 | mrec = map_mft_record(base_ni); | |
436 | if (IS_ERR(mrec)) { | |
437 | err = PTR_ERR(mrec); | |
438 | goto err_out; | |
439 | } | |
905685f6 AA |
440 | /* |
441 | * If a parallel write made the attribute non-resident, drop the mft | |
442 | * record and retry the readpage. | |
443 | */ | |
444 | if (unlikely(NInoNonResident(ni))) { | |
445 | unmap_mft_record(base_ni); | |
446 | goto retry_readpage; | |
447 | } | |
1da177e4 LT |
448 | ctx = ntfs_attr_get_search_ctx(base_ni, mrec); |
449 | if (unlikely(!ctx)) { | |
450 | err = -ENOMEM; | |
451 | goto unm_err_out; | |
452 | } | |
453 | err = ntfs_attr_lookup(ni->type, ni->name, ni->name_len, | |
454 | CASE_SENSITIVE, 0, NULL, 0, ctx); | |
455 | if (unlikely(err)) | |
456 | goto put_unm_err_out; | |
457 | attr_len = le32_to_cpu(ctx->attr->data.resident.value_length); | |
b6ad6c52 AA |
458 | read_lock_irqsave(&ni->size_lock, flags); |
459 | if (unlikely(attr_len > ni->initialized_size)) | |
460 | attr_len = ni->initialized_size; | |
461 | read_unlock_irqrestore(&ni->size_lock, flags); | |
1da177e4 LT |
462 | kaddr = kmap_atomic(page, KM_USER0); |
463 | /* Copy the data to the page. */ | |
464 | memcpy(kaddr, (u8*)ctx->attr + | |
465 | le16_to_cpu(ctx->attr->data.resident.value_offset), | |
466 | attr_len); | |
467 | /* Zero the remainder of the page. */ | |
468 | memset(kaddr + attr_len, 0, PAGE_CACHE_SIZE - attr_len); | |
469 | flush_dcache_page(page); | |
470 | kunmap_atomic(kaddr, KM_USER0); | |
471 | put_unm_err_out: | |
472 | ntfs_attr_put_search_ctx(ctx); | |
473 | unm_err_out: | |
474 | unmap_mft_record(base_ni); | |
475 | done: | |
476 | SetPageUptodate(page); | |
477 | err_out: | |
478 | unlock_page(page); | |
479 | return err; | |
480 | } | |
481 | ||
482 | #ifdef NTFS_RW | |
483 | ||
484 | /** | |
485 | * ntfs_write_block - write a @page to the backing store | |
486 | * @page: page cache page to write out | |
487 | * @wbc: writeback control structure | |
488 | * | |
489 | * This function is for writing pages belonging to non-resident, non-mst | |
490 | * protected attributes to their backing store. | |
491 | * | |
492 | * For a page with buffers, map and write the dirty buffers asynchronously | |
493 | * under page writeback. For a page without buffers, create buffers for the | |
494 | * page, then proceed as above. | |
495 | * | |
496 | * If a page doesn't have buffers the page dirty state is definitive. If a page | |
497 | * does have buffers, the page dirty state is just a hint, and the buffer dirty | |
498 | * state is definitive. (A hint which has rules: dirty buffers against a clean | |
499 | * page is illegal. Other combinations are legal and need to be handled. In | |
500 | * particular a dirty page containing clean buffers for example.) | |
501 | * | |
502 | * Return 0 on success and -errno on error. | |
503 | * | |
504 | * Based on ntfs_read_block() and __block_write_full_page(). | |
505 | */ | |
506 | static int ntfs_write_block(struct page *page, struct writeback_control *wbc) | |
507 | { | |
508 | VCN vcn; | |
509 | LCN lcn; | |
07a4e2da AA |
510 | s64 initialized_size; |
511 | loff_t i_size; | |
1da177e4 LT |
512 | sector_t block, dblock, iblock; |
513 | struct inode *vi; | |
514 | ntfs_inode *ni; | |
515 | ntfs_volume *vol; | |
516 | runlist_element *rl; | |
517 | struct buffer_head *bh, *head; | |
07a4e2da | 518 | unsigned long flags; |
1da177e4 LT |
519 | unsigned int blocksize, vcn_ofs; |
520 | int err; | |
521 | BOOL need_end_writeback; | |
522 | unsigned char blocksize_bits; | |
523 | ||
524 | vi = page->mapping->host; | |
525 | ni = NTFS_I(vi); | |
526 | vol = ni->vol; | |
527 | ||
528 | ntfs_debug("Entering for inode 0x%lx, attribute type 0x%x, page index " | |
529 | "0x%lx.", ni->mft_no, ni->type, page->index); | |
530 | ||
531 | BUG_ON(!NInoNonResident(ni)); | |
532 | BUG_ON(NInoMstProtected(ni)); | |
533 | ||
534 | blocksize_bits = vi->i_blkbits; | |
535 | blocksize = 1 << blocksize_bits; | |
536 | ||
537 | if (!page_has_buffers(page)) { | |
538 | BUG_ON(!PageUptodate(page)); | |
539 | create_empty_buffers(page, blocksize, | |
540 | (1 << BH_Uptodate) | (1 << BH_Dirty)); | |
a01ac532 AA |
541 | if (unlikely(!page_has_buffers(page))) { |
542 | ntfs_warning(vol->sb, "Error allocating page " | |
543 | "buffers. Redirtying page so we try " | |
544 | "again later."); | |
545 | /* | |
546 | * Put the page back on mapping->dirty_pages, but leave | |
547 | * its buffers' dirty state as-is. | |
548 | */ | |
549 | redirty_page_for_writepage(wbc, page); | |
550 | unlock_page(page); | |
551 | return 0; | |
552 | } | |
1da177e4 LT |
553 | } |
554 | bh = head = page_buffers(page); | |
a01ac532 | 555 | BUG_ON(!bh); |
1da177e4 LT |
556 | |
557 | /* NOTE: Different naming scheme to ntfs_read_block()! */ | |
558 | ||
559 | /* The first block in the page. */ | |
560 | block = (s64)page->index << (PAGE_CACHE_SHIFT - blocksize_bits); | |
561 | ||
07a4e2da AA |
562 | read_lock_irqsave(&ni->size_lock, flags); |
563 | i_size = i_size_read(vi); | |
564 | initialized_size = ni->initialized_size; | |
565 | read_unlock_irqrestore(&ni->size_lock, flags); | |
566 | ||
1da177e4 | 567 | /* The first out of bounds block for the data size. */ |
07a4e2da | 568 | dblock = (i_size + blocksize - 1) >> blocksize_bits; |
1da177e4 LT |
569 | |
570 | /* The last (fully or partially) initialized block. */ | |
07a4e2da | 571 | iblock = initialized_size >> blocksize_bits; |
1da177e4 LT |
572 | |
573 | /* | |
574 | * Be very careful. We have no exclusion from __set_page_dirty_buffers | |
575 | * here, and the (potentially unmapped) buffers may become dirty at | |
576 | * any time. If a buffer becomes dirty here after we've inspected it | |
577 | * then we just miss that fact, and the page stays dirty. | |
578 | * | |
579 | * Buffers outside i_size may be dirtied by __set_page_dirty_buffers; | |
580 | * handle that here by just cleaning them. | |
581 | */ | |
582 | ||
583 | /* | |
584 | * Loop through all the buffers in the page, mapping all the dirty | |
585 | * buffers to disk addresses and handling any aliases from the | |
586 | * underlying block device's mapping. | |
587 | */ | |
588 | rl = NULL; | |
589 | err = 0; | |
590 | do { | |
591 | BOOL is_retry = FALSE; | |
592 | ||
593 | if (unlikely(block >= dblock)) { | |
594 | /* | |
595 | * Mapped buffers outside i_size will occur, because | |
596 | * this page can be outside i_size when there is a | |
597 | * truncate in progress. The contents of such buffers | |
598 | * were zeroed by ntfs_writepage(). | |
599 | * | |
600 | * FIXME: What about the small race window where | |
601 | * ntfs_writepage() has not done any clearing because | |
602 | * the page was within i_size but before we get here, | |
603 | * vmtruncate() modifies i_size? | |
604 | */ | |
605 | clear_buffer_dirty(bh); | |
606 | set_buffer_uptodate(bh); | |
607 | continue; | |
608 | } | |
609 | ||
610 | /* Clean buffers are not written out, so no need to map them. */ | |
611 | if (!buffer_dirty(bh)) | |
612 | continue; | |
613 | ||
614 | /* Make sure we have enough initialized size. */ | |
615 | if (unlikely((block >= iblock) && | |
07a4e2da | 616 | (initialized_size < i_size))) { |
1da177e4 LT |
617 | /* |
618 | * If this page is fully outside initialized size, zero | |
619 | * out all pages between the current initialized size | |
620 | * and the current page. Just use ntfs_readpage() to do | |
621 | * the zeroing transparently. | |
622 | */ | |
623 | if (block > iblock) { | |
624 | // TODO: | |
625 | // For each page do: | |
626 | // - read_cache_page() | |
627 | // Again for each page do: | |
628 | // - wait_on_page_locked() | |
629 | // - Check (PageUptodate(page) && | |
630 | // !PageError(page)) | |
631 | // Update initialized size in the attribute and | |
632 | // in the inode. | |
633 | // Again, for each page do: | |
634 | // __set_page_dirty_buffers(); | |
635 | // page_cache_release() | |
636 | // We don't need to wait on the writes. | |
637 | // Update iblock. | |
638 | } | |
639 | /* | |
640 | * The current page straddles initialized size. Zero | |
641 | * all non-uptodate buffers and set them uptodate (and | |
642 | * dirty?). Note, there aren't any non-uptodate buffers | |
643 | * if the page is uptodate. | |
644 | * FIXME: For an uptodate page, the buffers may need to | |
645 | * be written out because they were not initialized on | |
646 | * disk before. | |
647 | */ | |
648 | if (!PageUptodate(page)) { | |
649 | // TODO: | |
650 | // Zero any non-uptodate buffers up to i_size. | |
651 | // Set them uptodate and dirty. | |
652 | } | |
653 | // TODO: | |
654 | // Update initialized size in the attribute and in the | |
655 | // inode (up to i_size). | |
656 | // Update iblock. | |
657 | // FIXME: This is inefficient. Try to batch the two | |
658 | // size changes to happen in one go. | |
659 | ntfs_error(vol->sb, "Writing beyond initialized size " | |
660 | "is not supported yet. Sorry."); | |
661 | err = -EOPNOTSUPP; | |
662 | break; | |
663 | // Do NOT set_buffer_new() BUT DO clear buffer range | |
664 | // outside write request range. | |
665 | // set_buffer_uptodate() on complete buffers as well as | |
666 | // set_buffer_dirty(). | |
667 | } | |
668 | ||
669 | /* No need to map buffers that are already mapped. */ | |
670 | if (buffer_mapped(bh)) | |
671 | continue; | |
672 | ||
673 | /* Unmapped, dirty buffer. Need to map it. */ | |
674 | bh->b_bdev = vol->sb->s_bdev; | |
675 | ||
676 | /* Convert block into corresponding vcn and offset. */ | |
677 | vcn = (VCN)block << blocksize_bits; | |
678 | vcn_ofs = vcn & vol->cluster_size_mask; | |
679 | vcn >>= vol->cluster_size_bits; | |
680 | if (!rl) { | |
681 | lock_retry_remap: | |
682 | down_read(&ni->runlist.lock); | |
683 | rl = ni->runlist.rl; | |
684 | } | |
685 | if (likely(rl != NULL)) { | |
686 | /* Seek to element containing target vcn. */ | |
687 | while (rl->length && rl[1].vcn <= vcn) | |
688 | rl++; | |
689 | lcn = ntfs_rl_vcn_to_lcn(rl, vcn); | |
690 | } else | |
691 | lcn = LCN_RL_NOT_MAPPED; | |
692 | /* Successful remap. */ | |
693 | if (lcn >= 0) { | |
694 | /* Setup buffer head to point to correct block. */ | |
695 | bh->b_blocknr = ((lcn << vol->cluster_size_bits) + | |
696 | vcn_ofs) >> blocksize_bits; | |
697 | set_buffer_mapped(bh); | |
698 | continue; | |
699 | } | |
700 | /* It is a hole, need to instantiate it. */ | |
701 | if (lcn == LCN_HOLE) { | |
8dcdebaf AA |
702 | u8 *kaddr; |
703 | unsigned long *bpos, *bend; | |
704 | ||
705 | /* Check if the buffer is zero. */ | |
706 | kaddr = kmap_atomic(page, KM_USER0); | |
707 | bpos = (unsigned long *)(kaddr + bh_offset(bh)); | |
708 | bend = (unsigned long *)((u8*)bpos + blocksize); | |
709 | do { | |
710 | if (unlikely(*bpos)) | |
711 | break; | |
712 | } while (likely(++bpos < bend)); | |
713 | kunmap_atomic(kaddr, KM_USER0); | |
714 | if (bpos == bend) { | |
715 | /* | |
716 | * Buffer is zero and sparse, no need to write | |
717 | * it. | |
718 | */ | |
719 | bh->b_blocknr = -1; | |
720 | clear_buffer_dirty(bh); | |
721 | continue; | |
722 | } | |
1da177e4 LT |
723 | // TODO: Instantiate the hole. |
724 | // clear_buffer_new(bh); | |
725 | // unmap_underlying_metadata(bh->b_bdev, bh->b_blocknr); | |
726 | ntfs_error(vol->sb, "Writing into sparse regions is " | |
727 | "not supported yet. Sorry."); | |
728 | err = -EOPNOTSUPP; | |
729 | break; | |
730 | } | |
731 | /* If first try and runlist unmapped, map and retry. */ | |
732 | if (!is_retry && lcn == LCN_RL_NOT_MAPPED) { | |
733 | is_retry = TRUE; | |
734 | /* | |
735 | * Attempt to map runlist, dropping lock for | |
736 | * the duration. | |
737 | */ | |
738 | up_read(&ni->runlist.lock); | |
739 | err = ntfs_map_runlist(ni, vcn); | |
740 | if (likely(!err)) | |
741 | goto lock_retry_remap; | |
742 | rl = NULL; | |
9f993fe4 AA |
743 | } else if (!rl) |
744 | up_read(&ni->runlist.lock); | |
8273d5d4 AA |
745 | /* |
746 | * If buffer is outside the runlist, truncate has cut it out | |
747 | * of the runlist. Just clean and clear the buffer and set it | |
748 | * uptodate so it can get discarded by the VM. | |
749 | */ | |
750 | if (err == -ENOENT || lcn == LCN_ENOENT) { | |
751 | u8 *kaddr; | |
752 | ||
753 | bh->b_blocknr = -1; | |
754 | clear_buffer_dirty(bh); | |
755 | kaddr = kmap_atomic(page, KM_USER0); | |
756 | memset(kaddr + bh_offset(bh), 0, blocksize); | |
757 | kunmap_atomic(kaddr, KM_USER0); | |
758 | flush_dcache_page(page); | |
759 | set_buffer_uptodate(bh); | |
760 | err = 0; | |
761 | continue; | |
762 | } | |
1da177e4 | 763 | /* Failed to map the buffer, even after retrying. */ |
8273d5d4 AA |
764 | if (!err) |
765 | err = -EIO; | |
1da177e4 LT |
766 | bh->b_blocknr = -1; |
767 | ntfs_error(vol->sb, "Failed to write to inode 0x%lx, " | |
768 | "attribute type 0x%x, vcn 0x%llx, offset 0x%x " | |
769 | "because its location on disk could not be " | |
8273d5d4 | 770 | "determined%s (error code %i).", ni->mft_no, |
1da177e4 LT |
771 | ni->type, (unsigned long long)vcn, |
772 | vcn_ofs, is_retry ? " even after " | |
8273d5d4 | 773 | "retrying" : "", err); |
1da177e4 LT |
774 | break; |
775 | } while (block++, (bh = bh->b_this_page) != head); | |
776 | ||
777 | /* Release the lock if we took it. */ | |
778 | if (rl) | |
779 | up_read(&ni->runlist.lock); | |
780 | ||
781 | /* For the error case, need to reset bh to the beginning. */ | |
782 | bh = head; | |
783 | ||
54b02eb0 | 784 | /* Just an optimization, so ->readpage() is not called later. */ |
1da177e4 LT |
785 | if (unlikely(!PageUptodate(page))) { |
786 | int uptodate = 1; | |
787 | do { | |
788 | if (!buffer_uptodate(bh)) { | |
789 | uptodate = 0; | |
790 | bh = head; | |
791 | break; | |
792 | } | |
793 | } while ((bh = bh->b_this_page) != head); | |
794 | if (uptodate) | |
795 | SetPageUptodate(page); | |
796 | } | |
797 | ||
798 | /* Setup all mapped, dirty buffers for async write i/o. */ | |
799 | do { | |
1da177e4 LT |
800 | if (buffer_mapped(bh) && buffer_dirty(bh)) { |
801 | lock_buffer(bh); | |
802 | if (test_clear_buffer_dirty(bh)) { | |
803 | BUG_ON(!buffer_uptodate(bh)); | |
804 | mark_buffer_async_write(bh); | |
805 | } else | |
806 | unlock_buffer(bh); | |
807 | } else if (unlikely(err)) { | |
808 | /* | |
809 | * For the error case. The buffer may have been set | |
810 | * dirty during attachment to a dirty page. | |
811 | */ | |
812 | if (err != -ENOMEM) | |
813 | clear_buffer_dirty(bh); | |
814 | } | |
815 | } while ((bh = bh->b_this_page) != head); | |
816 | ||
817 | if (unlikely(err)) { | |
818 | // TODO: Remove the -EOPNOTSUPP check later on... | |
819 | if (unlikely(err == -EOPNOTSUPP)) | |
820 | err = 0; | |
821 | else if (err == -ENOMEM) { | |
822 | ntfs_warning(vol->sb, "Error allocating memory. " | |
823 | "Redirtying page so we try again " | |
824 | "later."); | |
825 | /* | |
826 | * Put the page back on mapping->dirty_pages, but | |
827 | * leave its buffer's dirty state as-is. | |
828 | */ | |
829 | redirty_page_for_writepage(wbc, page); | |
830 | err = 0; | |
831 | } else | |
832 | SetPageError(page); | |
833 | } | |
834 | ||
835 | BUG_ON(PageWriteback(page)); | |
836 | set_page_writeback(page); /* Keeps try_to_free_buffers() away. */ | |
1da177e4 | 837 | |
54b02eb0 | 838 | /* Submit the prepared buffers for i/o. */ |
1da177e4 LT |
839 | need_end_writeback = TRUE; |
840 | do { | |
841 | struct buffer_head *next = bh->b_this_page; | |
842 | if (buffer_async_write(bh)) { | |
843 | submit_bh(WRITE, bh); | |
844 | need_end_writeback = FALSE; | |
845 | } | |
1da177e4 LT |
846 | bh = next; |
847 | } while (bh != head); | |
54b02eb0 | 848 | unlock_page(page); |
1da177e4 LT |
849 | |
850 | /* If no i/o was started, need to end_page_writeback(). */ | |
851 | if (unlikely(need_end_writeback)) | |
852 | end_page_writeback(page); | |
853 | ||
854 | ntfs_debug("Done."); | |
855 | return err; | |
856 | } | |
857 | ||
858 | /** | |
859 | * ntfs_write_mst_block - write a @page to the backing store | |
860 | * @page: page cache page to write out | |
861 | * @wbc: writeback control structure | |
862 | * | |
863 | * This function is for writing pages belonging to non-resident, mst protected | |
864 | * attributes to their backing store. The only supported attributes are index | |
865 | * allocation and $MFT/$DATA. Both directory inodes and index inodes are | |
866 | * supported for the index allocation case. | |
867 | * | |
868 | * The page must remain locked for the duration of the write because we apply | |
869 | * the mst fixups, write, and then undo the fixups, so if we were to unlock the | |
870 | * page before undoing the fixups, any other user of the page will see the | |
871 | * page contents as corrupt. | |
872 | * | |
873 | * We clear the page uptodate flag for the duration of the function to ensure | |
874 | * exclusion for the $MFT/$DATA case against someone mapping an mft record we | |
875 | * are about to apply the mst fixups to. | |
876 | * | |
877 | * Return 0 on success and -errno on error. | |
878 | * | |
879 | * Based on ntfs_write_block(), ntfs_mft_writepage(), and | |
880 | * write_mft_record_nolock(). | |
881 | */ | |
882 | static int ntfs_write_mst_block(struct page *page, | |
883 | struct writeback_control *wbc) | |
884 | { | |
885 | sector_t block, dblock, rec_block; | |
886 | struct inode *vi = page->mapping->host; | |
887 | ntfs_inode *ni = NTFS_I(vi); | |
888 | ntfs_volume *vol = ni->vol; | |
889 | u8 *kaddr; | |
1da177e4 LT |
890 | unsigned int rec_size = ni->itype.index.block_size; |
891 | ntfs_inode *locked_nis[PAGE_CACHE_SIZE / rec_size]; | |
892 | struct buffer_head *bh, *head, *tbh, *rec_start_bh; | |
d53ee322 | 893 | struct buffer_head *bhs[MAX_BUF_PER_PAGE]; |
1da177e4 | 894 | runlist_element *rl; |
d53ee322 AA |
895 | int i, nr_locked_nis, nr_recs, nr_bhs, max_bhs, bhs_per_rec, err, err2; |
896 | unsigned bh_size, rec_size_bits; | |
1da177e4 | 897 | BOOL sync, is_mft, page_is_dirty, rec_is_dirty; |
d53ee322 | 898 | unsigned char bh_size_bits; |
1da177e4 LT |
899 | |
900 | ntfs_debug("Entering for inode 0x%lx, attribute type 0x%x, page index " | |
901 | "0x%lx.", vi->i_ino, ni->type, page->index); | |
902 | BUG_ON(!NInoNonResident(ni)); | |
903 | BUG_ON(!NInoMstProtected(ni)); | |
904 | is_mft = (S_ISREG(vi->i_mode) && !vi->i_ino); | |
905 | /* | |
906 | * NOTE: ntfs_write_mst_block() would be called for $MFTMirr if a page | |
907 | * in its page cache were to be marked dirty. However this should | |
908 | * never happen with the current driver and considering we do not | |
909 | * handle this case here we do want to BUG(), at least for now. | |
910 | */ | |
911 | BUG_ON(!(is_mft || S_ISDIR(vi->i_mode) || | |
912 | (NInoAttr(ni) && ni->type == AT_INDEX_ALLOCATION))); | |
d53ee322 AA |
913 | bh_size_bits = vi->i_blkbits; |
914 | bh_size = 1 << bh_size_bits; | |
915 | max_bhs = PAGE_CACHE_SIZE / bh_size; | |
1da177e4 | 916 | BUG_ON(!max_bhs); |
d53ee322 | 917 | BUG_ON(max_bhs > MAX_BUF_PER_PAGE); |
1da177e4 LT |
918 | |
919 | /* Were we called for sync purposes? */ | |
920 | sync = (wbc->sync_mode == WB_SYNC_ALL); | |
921 | ||
922 | /* Make sure we have mapped buffers. */ | |
1da177e4 LT |
923 | bh = head = page_buffers(page); |
924 | BUG_ON(!bh); | |
925 | ||
926 | rec_size_bits = ni->itype.index.block_size_bits; | |
927 | BUG_ON(!(PAGE_CACHE_SIZE >> rec_size_bits)); | |
928 | bhs_per_rec = rec_size >> bh_size_bits; | |
929 | BUG_ON(!bhs_per_rec); | |
930 | ||
931 | /* The first block in the page. */ | |
932 | rec_block = block = (sector_t)page->index << | |
933 | (PAGE_CACHE_SHIFT - bh_size_bits); | |
934 | ||
935 | /* The first out of bounds block for the data size. */ | |
07a4e2da | 936 | dblock = (i_size_read(vi) + bh_size - 1) >> bh_size_bits; |
1da177e4 LT |
937 | |
938 | rl = NULL; | |
939 | err = err2 = nr_bhs = nr_recs = nr_locked_nis = 0; | |
940 | page_is_dirty = rec_is_dirty = FALSE; | |
941 | rec_start_bh = NULL; | |
942 | do { | |
943 | BOOL is_retry = FALSE; | |
944 | ||
945 | if (likely(block < rec_block)) { | |
946 | if (unlikely(block >= dblock)) { | |
947 | clear_buffer_dirty(bh); | |
946929d8 | 948 | set_buffer_uptodate(bh); |
1da177e4 LT |
949 | continue; |
950 | } | |
951 | /* | |
952 | * This block is not the first one in the record. We | |
953 | * ignore the buffer's dirty state because we could | |
954 | * have raced with a parallel mark_ntfs_record_dirty(). | |
955 | */ | |
956 | if (!rec_is_dirty) | |
957 | continue; | |
958 | if (unlikely(err2)) { | |
959 | if (err2 != -ENOMEM) | |
960 | clear_buffer_dirty(bh); | |
961 | continue; | |
962 | } | |
963 | } else /* if (block == rec_block) */ { | |
964 | BUG_ON(block > rec_block); | |
965 | /* This block is the first one in the record. */ | |
966 | rec_block += bhs_per_rec; | |
967 | err2 = 0; | |
968 | if (unlikely(block >= dblock)) { | |
969 | clear_buffer_dirty(bh); | |
970 | continue; | |
971 | } | |
972 | if (!buffer_dirty(bh)) { | |
973 | /* Clean records are not written out. */ | |
974 | rec_is_dirty = FALSE; | |
975 | continue; | |
976 | } | |
977 | rec_is_dirty = TRUE; | |
978 | rec_start_bh = bh; | |
979 | } | |
980 | /* Need to map the buffer if it is not mapped already. */ | |
981 | if (unlikely(!buffer_mapped(bh))) { | |
982 | VCN vcn; | |
983 | LCN lcn; | |
984 | unsigned int vcn_ofs; | |
985 | ||
481d0374 | 986 | bh->b_bdev = vol->sb->s_bdev; |
1da177e4 LT |
987 | /* Obtain the vcn and offset of the current block. */ |
988 | vcn = (VCN)block << bh_size_bits; | |
989 | vcn_ofs = vcn & vol->cluster_size_mask; | |
990 | vcn >>= vol->cluster_size_bits; | |
991 | if (!rl) { | |
992 | lock_retry_remap: | |
993 | down_read(&ni->runlist.lock); | |
994 | rl = ni->runlist.rl; | |
995 | } | |
996 | if (likely(rl != NULL)) { | |
997 | /* Seek to element containing target vcn. */ | |
998 | while (rl->length && rl[1].vcn <= vcn) | |
999 | rl++; | |
1000 | lcn = ntfs_rl_vcn_to_lcn(rl, vcn); | |
1001 | } else | |
1002 | lcn = LCN_RL_NOT_MAPPED; | |
1003 | /* Successful remap. */ | |
1004 | if (likely(lcn >= 0)) { | |
1005 | /* Setup buffer head to correct block. */ | |
1006 | bh->b_blocknr = ((lcn << | |
1007 | vol->cluster_size_bits) + | |
1008 | vcn_ofs) >> bh_size_bits; | |
1009 | set_buffer_mapped(bh); | |
1010 | } else { | |
1011 | /* | |
1012 | * Remap failed. Retry to map the runlist once | |
1013 | * unless we are working on $MFT which always | |
1014 | * has the whole of its runlist in memory. | |
1015 | */ | |
1016 | if (!is_mft && !is_retry && | |
1017 | lcn == LCN_RL_NOT_MAPPED) { | |
1018 | is_retry = TRUE; | |
1019 | /* | |
1020 | * Attempt to map runlist, dropping | |
1021 | * lock for the duration. | |
1022 | */ | |
1023 | up_read(&ni->runlist.lock); | |
1024 | err2 = ntfs_map_runlist(ni, vcn); | |
1025 | if (likely(!err2)) | |
1026 | goto lock_retry_remap; | |
1027 | if (err2 == -ENOMEM) | |
1028 | page_is_dirty = TRUE; | |
1029 | lcn = err2; | |
9f993fe4 | 1030 | } else { |
1da177e4 | 1031 | err2 = -EIO; |
9f993fe4 AA |
1032 | if (!rl) |
1033 | up_read(&ni->runlist.lock); | |
1034 | } | |
1da177e4 LT |
1035 | /* Hard error. Abort writing this record. */ |
1036 | if (!err || err == -ENOMEM) | |
1037 | err = err2; | |
1038 | bh->b_blocknr = -1; | |
1039 | ntfs_error(vol->sb, "Cannot write ntfs record " | |
1040 | "0x%llx (inode 0x%lx, " | |
1041 | "attribute type 0x%x) because " | |
1042 | "its location on disk could " | |
1043 | "not be determined (error " | |
8907547d RD |
1044 | "code %lli).", |
1045 | (long long)block << | |
1da177e4 LT |
1046 | bh_size_bits >> |
1047 | vol->mft_record_size_bits, | |
1048 | ni->mft_no, ni->type, | |
1049 | (long long)lcn); | |
1050 | /* | |
1051 | * If this is not the first buffer, remove the | |
1052 | * buffers in this record from the list of | |
1053 | * buffers to write and clear their dirty bit | |
1054 | * if not error -ENOMEM. | |
1055 | */ | |
1056 | if (rec_start_bh != bh) { | |
1057 | while (bhs[--nr_bhs] != rec_start_bh) | |
1058 | ; | |
1059 | if (err2 != -ENOMEM) { | |
1060 | do { | |
1061 | clear_buffer_dirty( | |
1062 | rec_start_bh); | |
1063 | } while ((rec_start_bh = | |
1064 | rec_start_bh-> | |
1065 | b_this_page) != | |
1066 | bh); | |
1067 | } | |
1068 | } | |
1069 | continue; | |
1070 | } | |
1071 | } | |
1072 | BUG_ON(!buffer_uptodate(bh)); | |
1073 | BUG_ON(nr_bhs >= max_bhs); | |
1074 | bhs[nr_bhs++] = bh; | |
1075 | } while (block++, (bh = bh->b_this_page) != head); | |
1076 | if (unlikely(rl)) | |
1077 | up_read(&ni->runlist.lock); | |
1078 | /* If there were no dirty buffers, we are done. */ | |
1079 | if (!nr_bhs) | |
1080 | goto done; | |
1081 | /* Map the page so we can access its contents. */ | |
1082 | kaddr = kmap(page); | |
1083 | /* Clear the page uptodate flag whilst the mst fixups are applied. */ | |
1084 | BUG_ON(!PageUptodate(page)); | |
1085 | ClearPageUptodate(page); | |
1086 | for (i = 0; i < nr_bhs; i++) { | |
1087 | unsigned int ofs; | |
1088 | ||
1089 | /* Skip buffers which are not at the beginning of records. */ | |
1090 | if (i % bhs_per_rec) | |
1091 | continue; | |
1092 | tbh = bhs[i]; | |
1093 | ofs = bh_offset(tbh); | |
1094 | if (is_mft) { | |
1095 | ntfs_inode *tni; | |
1096 | unsigned long mft_no; | |
1097 | ||
1098 | /* Get the mft record number. */ | |
1099 | mft_no = (((s64)page->index << PAGE_CACHE_SHIFT) + ofs) | |
1100 | >> rec_size_bits; | |
1101 | /* Check whether to write this mft record. */ | |
1102 | tni = NULL; | |
1103 | if (!ntfs_may_write_mft_record(vol, mft_no, | |
1104 | (MFT_RECORD*)(kaddr + ofs), &tni)) { | |
1105 | /* | |
1106 | * The record should not be written. This | |
1107 | * means we need to redirty the page before | |
1108 | * returning. | |
1109 | */ | |
1110 | page_is_dirty = TRUE; | |
1111 | /* | |
1112 | * Remove the buffers in this mft record from | |
1113 | * the list of buffers to write. | |
1114 | */ | |
1115 | do { | |
1116 | bhs[i] = NULL; | |
1117 | } while (++i % bhs_per_rec); | |
1118 | continue; | |
1119 | } | |
1120 | /* | |
1121 | * The record should be written. If a locked ntfs | |
1122 | * inode was returned, add it to the array of locked | |
1123 | * ntfs inodes. | |
1124 | */ | |
1125 | if (tni) | |
1126 | locked_nis[nr_locked_nis++] = tni; | |
1127 | } | |
1128 | /* Apply the mst protection fixups. */ | |
1129 | err2 = pre_write_mst_fixup((NTFS_RECORD*)(kaddr + ofs), | |
1130 | rec_size); | |
1131 | if (unlikely(err2)) { | |
1132 | if (!err || err == -ENOMEM) | |
1133 | err = -EIO; | |
1134 | ntfs_error(vol->sb, "Failed to apply mst fixups " | |
1135 | "(inode 0x%lx, attribute type 0x%x, " | |
1136 | "page index 0x%lx, page offset 0x%x)!" | |
1137 | " Unmount and run chkdsk.", vi->i_ino, | |
1138 | ni->type, page->index, ofs); | |
1139 | /* | |
1140 | * Mark all the buffers in this record clean as we do | |
1141 | * not want to write corrupt data to disk. | |
1142 | */ | |
1143 | do { | |
1144 | clear_buffer_dirty(bhs[i]); | |
1145 | bhs[i] = NULL; | |
1146 | } while (++i % bhs_per_rec); | |
1147 | continue; | |
1148 | } | |
1149 | nr_recs++; | |
1150 | } | |
1151 | /* If no records are to be written out, we are done. */ | |
1152 | if (!nr_recs) | |
1153 | goto unm_done; | |
1154 | flush_dcache_page(page); | |
1155 | /* Lock buffers and start synchronous write i/o on them. */ | |
1156 | for (i = 0; i < nr_bhs; i++) { | |
1157 | tbh = bhs[i]; | |
1158 | if (!tbh) | |
1159 | continue; | |
1160 | if (unlikely(test_set_buffer_locked(tbh))) | |
1161 | BUG(); | |
1162 | /* The buffer dirty state is now irrelevant, just clean it. */ | |
1163 | clear_buffer_dirty(tbh); | |
1164 | BUG_ON(!buffer_uptodate(tbh)); | |
1165 | BUG_ON(!buffer_mapped(tbh)); | |
1166 | get_bh(tbh); | |
1167 | tbh->b_end_io = end_buffer_write_sync; | |
1168 | submit_bh(WRITE, tbh); | |
1169 | } | |
1170 | /* Synchronize the mft mirror now if not @sync. */ | |
1171 | if (is_mft && !sync) | |
1172 | goto do_mirror; | |
1173 | do_wait: | |
1174 | /* Wait on i/o completion of buffers. */ | |
1175 | for (i = 0; i < nr_bhs; i++) { | |
1176 | tbh = bhs[i]; | |
1177 | if (!tbh) | |
1178 | continue; | |
1179 | wait_on_buffer(tbh); | |
1180 | if (unlikely(!buffer_uptodate(tbh))) { | |
1181 | ntfs_error(vol->sb, "I/O error while writing ntfs " | |
1182 | "record buffer (inode 0x%lx, " | |
1183 | "attribute type 0x%x, page index " | |
1184 | "0x%lx, page offset 0x%lx)! Unmount " | |
1185 | "and run chkdsk.", vi->i_ino, ni->type, | |
1186 | page->index, bh_offset(tbh)); | |
1187 | if (!err || err == -ENOMEM) | |
1188 | err = -EIO; | |
1189 | /* | |
1190 | * Set the buffer uptodate so the page and buffer | |
1191 | * states do not become out of sync. | |
1192 | */ | |
1193 | set_buffer_uptodate(tbh); | |
1194 | } | |
1195 | } | |
1196 | /* If @sync, now synchronize the mft mirror. */ | |
1197 | if (is_mft && sync) { | |
1198 | do_mirror: | |
1199 | for (i = 0; i < nr_bhs; i++) { | |
1200 | unsigned long mft_no; | |
1201 | unsigned int ofs; | |
1202 | ||
1203 | /* | |
1204 | * Skip buffers which are not at the beginning of | |
1205 | * records. | |
1206 | */ | |
1207 | if (i % bhs_per_rec) | |
1208 | continue; | |
1209 | tbh = bhs[i]; | |
1210 | /* Skip removed buffers (and hence records). */ | |
1211 | if (!tbh) | |
1212 | continue; | |
1213 | ofs = bh_offset(tbh); | |
1214 | /* Get the mft record number. */ | |
1215 | mft_no = (((s64)page->index << PAGE_CACHE_SHIFT) + ofs) | |
1216 | >> rec_size_bits; | |
1217 | if (mft_no < vol->mftmirr_size) | |
1218 | ntfs_sync_mft_mirror(vol, mft_no, | |
1219 | (MFT_RECORD*)(kaddr + ofs), | |
1220 | sync); | |
1221 | } | |
1222 | if (!sync) | |
1223 | goto do_wait; | |
1224 | } | |
1225 | /* Remove the mst protection fixups again. */ | |
1226 | for (i = 0; i < nr_bhs; i++) { | |
1227 | if (!(i % bhs_per_rec)) { | |
1228 | tbh = bhs[i]; | |
1229 | if (!tbh) | |
1230 | continue; | |
1231 | post_write_mst_fixup((NTFS_RECORD*)(kaddr + | |
1232 | bh_offset(tbh))); | |
1233 | } | |
1234 | } | |
1235 | flush_dcache_page(page); | |
1236 | unm_done: | |
1237 | /* Unlock any locked inodes. */ | |
1238 | while (nr_locked_nis-- > 0) { | |
1239 | ntfs_inode *tni, *base_tni; | |
1240 | ||
1241 | tni = locked_nis[nr_locked_nis]; | |
1242 | /* Get the base inode. */ | |
1243 | down(&tni->extent_lock); | |
1244 | if (tni->nr_extents >= 0) | |
1245 | base_tni = tni; | |
1246 | else { | |
1247 | base_tni = tni->ext.base_ntfs_ino; | |
1248 | BUG_ON(!base_tni); | |
1249 | } | |
1250 | up(&tni->extent_lock); | |
1251 | ntfs_debug("Unlocking %s inode 0x%lx.", | |
1252 | tni == base_tni ? "base" : "extent", | |
1253 | tni->mft_no); | |
1254 | up(&tni->mrec_lock); | |
1255 | atomic_dec(&tni->count); | |
1256 | iput(VFS_I(base_tni)); | |
1257 | } | |
1258 | SetPageUptodate(page); | |
1259 | kunmap(page); | |
1260 | done: | |
1261 | if (unlikely(err && err != -ENOMEM)) { | |
1262 | /* | |
1263 | * Set page error if there is only one ntfs record in the page. | |
1264 | * Otherwise we would loose per-record granularity. | |
1265 | */ | |
1266 | if (ni->itype.index.block_size == PAGE_CACHE_SIZE) | |
1267 | SetPageError(page); | |
1268 | NVolSetErrors(vol); | |
1269 | } | |
1270 | if (page_is_dirty) { | |
1271 | ntfs_debug("Page still contains one or more dirty ntfs " | |
1272 | "records. Redirtying the page starting at " | |
1273 | "record 0x%lx.", page->index << | |
1274 | (PAGE_CACHE_SHIFT - rec_size_bits)); | |
1275 | redirty_page_for_writepage(wbc, page); | |
1276 | unlock_page(page); | |
1277 | } else { | |
1278 | /* | |
1279 | * Keep the VM happy. This must be done otherwise the | |
1280 | * radix-tree tag PAGECACHE_TAG_DIRTY remains set even though | |
1281 | * the page is clean. | |
1282 | */ | |
1283 | BUG_ON(PageWriteback(page)); | |
1284 | set_page_writeback(page); | |
1285 | unlock_page(page); | |
1286 | end_page_writeback(page); | |
1287 | } | |
1288 | if (likely(!err)) | |
1289 | ntfs_debug("Done."); | |
1290 | return err; | |
1291 | } | |
1292 | ||
1293 | /** | |
1294 | * ntfs_writepage - write a @page to the backing store | |
1295 | * @page: page cache page to write out | |
1296 | * @wbc: writeback control structure | |
1297 | * | |
1298 | * This is called from the VM when it wants to have a dirty ntfs page cache | |
1299 | * page cleaned. The VM has already locked the page and marked it clean. | |
1300 | * | |
1301 | * For non-resident attributes, ntfs_writepage() writes the @page by calling | |
1302 | * the ntfs version of the generic block_write_full_page() function, | |
1303 | * ntfs_write_block(), which in turn if necessary creates and writes the | |
1304 | * buffers associated with the page asynchronously. | |
1305 | * | |
1306 | * For resident attributes, OTOH, ntfs_writepage() writes the @page by copying | |
1307 | * the data to the mft record (which at this stage is most likely in memory). | |
1308 | * The mft record is then marked dirty and written out asynchronously via the | |
1309 | * vfs inode dirty code path for the inode the mft record belongs to or via the | |
1310 | * vm page dirty code path for the page the mft record is in. | |
1311 | * | |
1312 | * Based on ntfs_readpage() and fs/buffer.c::block_write_full_page(). | |
1313 | * | |
1314 | * Return 0 on success and -errno on error. | |
1315 | */ | |
1316 | static int ntfs_writepage(struct page *page, struct writeback_control *wbc) | |
1317 | { | |
1318 | loff_t i_size; | |
149f0c52 AA |
1319 | struct inode *vi = page->mapping->host; |
1320 | ntfs_inode *base_ni = NULL, *ni = NTFS_I(vi); | |
1da177e4 | 1321 | char *kaddr; |
149f0c52 AA |
1322 | ntfs_attr_search_ctx *ctx = NULL; |
1323 | MFT_RECORD *m = NULL; | |
1da177e4 LT |
1324 | u32 attr_len; |
1325 | int err; | |
1326 | ||
905685f6 | 1327 | retry_writepage: |
1da177e4 | 1328 | BUG_ON(!PageLocked(page)); |
1da177e4 | 1329 | i_size = i_size_read(vi); |
1da177e4 LT |
1330 | /* Is the page fully outside i_size? (truncate in progress) */ |
1331 | if (unlikely(page->index >= (i_size + PAGE_CACHE_SIZE - 1) >> | |
1332 | PAGE_CACHE_SHIFT)) { | |
1333 | /* | |
1334 | * The page may have dirty, unmapped buffers. Make them | |
1335 | * freeable here, so the page does not leak. | |
1336 | */ | |
1337 | block_invalidatepage(page, 0); | |
1338 | unlock_page(page); | |
1339 | ntfs_debug("Write outside i_size - truncated?"); | |
1340 | return 0; | |
1341 | } | |
bd45fdd2 AA |
1342 | /* |
1343 | * Only $DATA attributes can be encrypted and only unnamed $DATA | |
1344 | * attributes can be compressed. Index root can have the flags set but | |
1345 | * this means to create compressed/encrypted files, not that the | |
4e64c886 AA |
1346 | * attribute is compressed/encrypted. Note we need to check for |
1347 | * AT_INDEX_ALLOCATION since this is the type of both directory and | |
1348 | * index inodes. | |
bd45fdd2 | 1349 | */ |
4e64c886 | 1350 | if (ni->type != AT_INDEX_ALLOCATION) { |
bd45fdd2 AA |
1351 | /* If file is encrypted, deny access, just like NT4. */ |
1352 | if (NInoEncrypted(ni)) { | |
1353 | unlock_page(page); | |
1354 | BUG_ON(ni->type != AT_DATA); | |
1355 | ntfs_debug("Denying write access to encrypted " | |
1356 | "file."); | |
1357 | return -EACCES; | |
1358 | } | |
1359 | /* Compressed data streams are handled in compress.c. */ | |
1360 | if (NInoNonResident(ni) && NInoCompressed(ni)) { | |
1361 | BUG_ON(ni->type != AT_DATA); | |
1362 | BUG_ON(ni->name_len); | |
1363 | // TODO: Implement and replace this with | |
1364 | // return ntfs_write_compressed_block(page); | |
1365 | unlock_page(page); | |
1366 | ntfs_error(vi->i_sb, "Writing to compressed files is " | |
1367 | "not supported yet. Sorry."); | |
1368 | return -EOPNOTSUPP; | |
1369 | } | |
1370 | // TODO: Implement and remove this check. | |
1371 | if (NInoNonResident(ni) && NInoSparse(ni)) { | |
1372 | unlock_page(page); | |
1373 | ntfs_error(vi->i_sb, "Writing to sparse files is not " | |
1374 | "supported yet. Sorry."); | |
1375 | return -EOPNOTSUPP; | |
1376 | } | |
1377 | } | |
1da177e4 LT |
1378 | /* NInoNonResident() == NInoIndexAllocPresent() */ |
1379 | if (NInoNonResident(ni)) { | |
1da177e4 LT |
1380 | /* We have to zero every time due to mmap-at-end-of-file. */ |
1381 | if (page->index >= (i_size >> PAGE_CACHE_SHIFT)) { | |
1382 | /* The page straddles i_size. */ | |
1383 | unsigned int ofs = i_size & ~PAGE_CACHE_MASK; | |
1384 | kaddr = kmap_atomic(page, KM_USER0); | |
1385 | memset(kaddr + ofs, 0, PAGE_CACHE_SIZE - ofs); | |
1386 | flush_dcache_page(page); | |
1387 | kunmap_atomic(kaddr, KM_USER0); | |
1388 | } | |
1389 | /* Handle mst protected attributes. */ | |
1390 | if (NInoMstProtected(ni)) | |
1391 | return ntfs_write_mst_block(page, wbc); | |
bd45fdd2 | 1392 | /* Normal, non-resident data stream. */ |
1da177e4 LT |
1393 | return ntfs_write_block(page, wbc); |
1394 | } | |
1395 | /* | |
bd45fdd2 AA |
1396 | * Attribute is resident, implying it is not compressed, encrypted, or |
1397 | * mst protected. This also means the attribute is smaller than an mft | |
1398 | * record and hence smaller than a page, so can simply return error on | |
1399 | * any pages with index above 0. Note the attribute can actually be | |
1400 | * marked compressed but if it is resident the actual data is not | |
1401 | * compressed so we are ok to ignore the compressed flag here. | |
1da177e4 LT |
1402 | */ |
1403 | BUG_ON(page_has_buffers(page)); | |
1404 | BUG_ON(!PageUptodate(page)); | |
1405 | if (unlikely(page->index > 0)) { | |
1406 | ntfs_error(vi->i_sb, "BUG()! page->index (0x%lx) > 0. " | |
1407 | "Aborting write.", page->index); | |
1408 | BUG_ON(PageWriteback(page)); | |
1409 | set_page_writeback(page); | |
1410 | unlock_page(page); | |
1411 | end_page_writeback(page); | |
1412 | return -EIO; | |
1413 | } | |
1414 | if (!NInoAttr(ni)) | |
1415 | base_ni = ni; | |
1416 | else | |
1417 | base_ni = ni->ext.base_ntfs_ino; | |
1418 | /* Map, pin, and lock the mft record. */ | |
1419 | m = map_mft_record(base_ni); | |
1420 | if (IS_ERR(m)) { | |
1421 | err = PTR_ERR(m); | |
1422 | m = NULL; | |
1423 | ctx = NULL; | |
1424 | goto err_out; | |
1425 | } | |
905685f6 AA |
1426 | /* |
1427 | * If a parallel write made the attribute non-resident, drop the mft | |
1428 | * record and retry the writepage. | |
1429 | */ | |
1430 | if (unlikely(NInoNonResident(ni))) { | |
1431 | unmap_mft_record(base_ni); | |
1432 | goto retry_writepage; | |
1433 | } | |
1da177e4 LT |
1434 | ctx = ntfs_attr_get_search_ctx(base_ni, m); |
1435 | if (unlikely(!ctx)) { | |
1436 | err = -ENOMEM; | |
1437 | goto err_out; | |
1438 | } | |
1439 | err = ntfs_attr_lookup(ni->type, ni->name, ni->name_len, | |
1440 | CASE_SENSITIVE, 0, NULL, 0, ctx); | |
1441 | if (unlikely(err)) | |
1442 | goto err_out; | |
1443 | /* | |
1444 | * Keep the VM happy. This must be done otherwise the radix-tree tag | |
1445 | * PAGECACHE_TAG_DIRTY remains set even though the page is clean. | |
1446 | */ | |
1447 | BUG_ON(PageWriteback(page)); | |
1448 | set_page_writeback(page); | |
1449 | unlock_page(page); | |
1da177e4 | 1450 | /* |
bd45fdd2 AA |
1451 | * Here, we do not need to zero the out of bounds area everytime |
1452 | * because the below memcpy() already takes care of the | |
1453 | * mmap-at-end-of-file requirements. If the file is converted to a | |
1454 | * non-resident one, then the code path use is switched to the | |
1455 | * non-resident one where the zeroing happens on each ntfs_writepage() | |
1456 | * invocation. | |
1da177e4 | 1457 | */ |
1da177e4 | 1458 | attr_len = le32_to_cpu(ctx->attr->data.resident.value_length); |
07a4e2da | 1459 | i_size = i_size_read(vi); |
1da177e4 | 1460 | if (unlikely(attr_len > i_size)) { |
1da177e4 | 1461 | attr_len = i_size; |
f40661be | 1462 | ctx->attr->data.resident.value_length = cpu_to_le32(attr_len); |
1da177e4 | 1463 | } |
f40661be | 1464 | kaddr = kmap_atomic(page, KM_USER0); |
1da177e4 LT |
1465 | /* Copy the data from the page to the mft record. */ |
1466 | memcpy((u8*)ctx->attr + | |
1467 | le16_to_cpu(ctx->attr->data.resident.value_offset), | |
1468 | kaddr, attr_len); | |
1469 | flush_dcache_mft_record_page(ctx->ntfs_ino); | |
1470 | /* Zero out of bounds area in the page cache page. */ | |
1471 | memset(kaddr + attr_len, 0, PAGE_CACHE_SIZE - attr_len); | |
1472 | flush_dcache_page(page); | |
1473 | kunmap_atomic(kaddr, KM_USER0); | |
1474 | ||
1475 | end_page_writeback(page); | |
1476 | ||
1477 | /* Mark the mft record dirty, so it gets written back. */ | |
1478 | mark_mft_record_dirty(ctx->ntfs_ino); | |
1479 | ntfs_attr_put_search_ctx(ctx); | |
1480 | unmap_mft_record(base_ni); | |
1481 | return 0; | |
1482 | err_out: | |
1483 | if (err == -ENOMEM) { | |
1484 | ntfs_warning(vi->i_sb, "Error allocating memory. Redirtying " | |
1485 | "page so we try again later."); | |
1486 | /* | |
1487 | * Put the page back on mapping->dirty_pages, but leave its | |
1488 | * buffers' dirty state as-is. | |
1489 | */ | |
1490 | redirty_page_for_writepage(wbc, page); | |
1491 | err = 0; | |
1492 | } else { | |
1493 | ntfs_error(vi->i_sb, "Resident attribute write failed with " | |
149f0c52 | 1494 | "error %i.", err); |
1da177e4 | 1495 | SetPageError(page); |
149f0c52 AA |
1496 | NVolSetErrors(ni->vol); |
1497 | make_bad_inode(vi); | |
1da177e4 LT |
1498 | } |
1499 | unlock_page(page); | |
1500 | if (ctx) | |
1501 | ntfs_attr_put_search_ctx(ctx); | |
1502 | if (m) | |
1503 | unmap_mft_record(base_ni); | |
1504 | return err; | |
1505 | } | |
1506 | ||
1507 | /** | |
1508 | * ntfs_prepare_nonresident_write - | |
1509 | * | |
1510 | */ | |
1511 | static int ntfs_prepare_nonresident_write(struct page *page, | |
1512 | unsigned from, unsigned to) | |
1513 | { | |
1514 | VCN vcn; | |
1515 | LCN lcn; | |
07a4e2da AA |
1516 | s64 initialized_size; |
1517 | loff_t i_size; | |
1da177e4 LT |
1518 | sector_t block, ablock, iblock; |
1519 | struct inode *vi; | |
1520 | ntfs_inode *ni; | |
1521 | ntfs_volume *vol; | |
1522 | runlist_element *rl; | |
1523 | struct buffer_head *bh, *head, *wait[2], **wait_bh = wait; | |
07a4e2da | 1524 | unsigned long flags; |
1da177e4 LT |
1525 | unsigned int vcn_ofs, block_start, block_end, blocksize; |
1526 | int err; | |
1527 | BOOL is_retry; | |
1528 | unsigned char blocksize_bits; | |
1529 | ||
1530 | vi = page->mapping->host; | |
1531 | ni = NTFS_I(vi); | |
1532 | vol = ni->vol; | |
1533 | ||
1534 | ntfs_debug("Entering for inode 0x%lx, attribute type 0x%x, page index " | |
1535 | "0x%lx, from = %u, to = %u.", ni->mft_no, ni->type, | |
1536 | page->index, from, to); | |
1537 | ||
1538 | BUG_ON(!NInoNonResident(ni)); | |
1539 | ||
1540 | blocksize_bits = vi->i_blkbits; | |
1541 | blocksize = 1 << blocksize_bits; | |
1542 | ||
1543 | /* | |
1544 | * create_empty_buffers() will create uptodate/dirty buffers if the | |
1545 | * page is uptodate/dirty. | |
1546 | */ | |
1547 | if (!page_has_buffers(page)) | |
1548 | create_empty_buffers(page, blocksize, 0); | |
1549 | bh = head = page_buffers(page); | |
1550 | if (unlikely(!bh)) | |
1551 | return -ENOMEM; | |
1552 | ||
1553 | /* The first block in the page. */ | |
1554 | block = (s64)page->index << (PAGE_CACHE_SHIFT - blocksize_bits); | |
1555 | ||
07a4e2da | 1556 | read_lock_irqsave(&ni->size_lock, flags); |
1da177e4 | 1557 | /* |
b6ad6c52 | 1558 | * The first out of bounds block for the allocated size. No need to |
1da177e4 LT |
1559 | * round up as allocated_size is in multiples of cluster size and the |
1560 | * minimum cluster size is 512 bytes, which is equal to the smallest | |
1561 | * blocksize. | |
1562 | */ | |
1563 | ablock = ni->allocated_size >> blocksize_bits; | |
07a4e2da AA |
1564 | i_size = i_size_read(vi); |
1565 | initialized_size = ni->initialized_size; | |
1566 | read_unlock_irqrestore(&ni->size_lock, flags); | |
1567 | ||
1da177e4 | 1568 | /* The last (fully or partially) initialized block. */ |
07a4e2da | 1569 | iblock = initialized_size >> blocksize_bits; |
1da177e4 LT |
1570 | |
1571 | /* Loop through all the buffers in the page. */ | |
1572 | block_start = 0; | |
1573 | rl = NULL; | |
1574 | err = 0; | |
1575 | do { | |
1576 | block_end = block_start + blocksize; | |
1577 | /* | |
1578 | * If buffer @bh is outside the write, just mark it uptodate | |
1579 | * if the page is uptodate and continue with the next buffer. | |
1580 | */ | |
1581 | if (block_end <= from || block_start >= to) { | |
1582 | if (PageUptodate(page)) { | |
1583 | if (!buffer_uptodate(bh)) | |
1584 | set_buffer_uptodate(bh); | |
1585 | } | |
1586 | continue; | |
1587 | } | |
1588 | /* | |
1589 | * @bh is at least partially being written to. | |
1590 | * Make sure it is not marked as new. | |
1591 | */ | |
1592 | //if (buffer_new(bh)) | |
1593 | // clear_buffer_new(bh); | |
1594 | ||
1595 | if (block >= ablock) { | |
1596 | // TODO: block is above allocated_size, need to | |
1597 | // allocate it. Best done in one go to accommodate not | |
1598 | // only block but all above blocks up to and including: | |
1599 | // ((page->index << PAGE_CACHE_SHIFT) + to + blocksize | |
1600 | // - 1) >> blobksize_bits. Obviously will need to round | |
1601 | // up to next cluster boundary, too. This should be | |
1602 | // done with a helper function, so it can be reused. | |
1603 | ntfs_error(vol->sb, "Writing beyond allocated size " | |
1604 | "is not supported yet. Sorry."); | |
1605 | err = -EOPNOTSUPP; | |
1606 | goto err_out; | |
1607 | // Need to update ablock. | |
1608 | // Need to set_buffer_new() on all block bhs that are | |
1609 | // newly allocated. | |
1610 | } | |
1611 | /* | |
1612 | * Now we have enough allocated size to fulfill the whole | |
1613 | * request, i.e. block < ablock is true. | |
1614 | */ | |
1615 | if (unlikely((block >= iblock) && | |
07a4e2da | 1616 | (initialized_size < i_size))) { |
1da177e4 LT |
1617 | /* |
1618 | * If this page is fully outside initialized size, zero | |
1619 | * out all pages between the current initialized size | |
1620 | * and the current page. Just use ntfs_readpage() to do | |
1621 | * the zeroing transparently. | |
1622 | */ | |
1623 | if (block > iblock) { | |
1624 | // TODO: | |
1625 | // For each page do: | |
1626 | // - read_cache_page() | |
1627 | // Again for each page do: | |
1628 | // - wait_on_page_locked() | |
1629 | // - Check (PageUptodate(page) && | |
1630 | // !PageError(page)) | |
1631 | // Update initialized size in the attribute and | |
1632 | // in the inode. | |
1633 | // Again, for each page do: | |
1634 | // __set_page_dirty_buffers(); | |
1635 | // page_cache_release() | |
1636 | // We don't need to wait on the writes. | |
1637 | // Update iblock. | |
1638 | } | |
1639 | /* | |
1640 | * The current page straddles initialized size. Zero | |
1641 | * all non-uptodate buffers and set them uptodate (and | |
1642 | * dirty?). Note, there aren't any non-uptodate buffers | |
1643 | * if the page is uptodate. | |
1644 | * FIXME: For an uptodate page, the buffers may need to | |
1645 | * be written out because they were not initialized on | |
1646 | * disk before. | |
1647 | */ | |
1648 | if (!PageUptodate(page)) { | |
1649 | // TODO: | |
1650 | // Zero any non-uptodate buffers up to i_size. | |
1651 | // Set them uptodate and dirty. | |
1652 | } | |
1653 | // TODO: | |
1654 | // Update initialized size in the attribute and in the | |
1655 | // inode (up to i_size). | |
1656 | // Update iblock. | |
1657 | // FIXME: This is inefficient. Try to batch the two | |
1658 | // size changes to happen in one go. | |
1659 | ntfs_error(vol->sb, "Writing beyond initialized size " | |
1660 | "is not supported yet. Sorry."); | |
1661 | err = -EOPNOTSUPP; | |
1662 | goto err_out; | |
1663 | // Do NOT set_buffer_new() BUT DO clear buffer range | |
1664 | // outside write request range. | |
1665 | // set_buffer_uptodate() on complete buffers as well as | |
1666 | // set_buffer_dirty(). | |
1667 | } | |
1668 | ||
1669 | /* Need to map unmapped buffers. */ | |
1670 | if (!buffer_mapped(bh)) { | |
1671 | /* Unmapped buffer. Need to map it. */ | |
1672 | bh->b_bdev = vol->sb->s_bdev; | |
1673 | ||
1674 | /* Convert block into corresponding vcn and offset. */ | |
1675 | vcn = (VCN)block << blocksize_bits >> | |
1676 | vol->cluster_size_bits; | |
1677 | vcn_ofs = ((VCN)block << blocksize_bits) & | |
1678 | vol->cluster_size_mask; | |
1679 | ||
1680 | is_retry = FALSE; | |
1681 | if (!rl) { | |
1682 | lock_retry_remap: | |
1683 | down_read(&ni->runlist.lock); | |
1684 | rl = ni->runlist.rl; | |
1685 | } | |
1686 | if (likely(rl != NULL)) { | |
1687 | /* Seek to element containing target vcn. */ | |
1688 | while (rl->length && rl[1].vcn <= vcn) | |
1689 | rl++; | |
1690 | lcn = ntfs_rl_vcn_to_lcn(rl, vcn); | |
1691 | } else | |
1692 | lcn = LCN_RL_NOT_MAPPED; | |
1693 | if (unlikely(lcn < 0)) { | |
1694 | /* | |
1695 | * We extended the attribute allocation above. | |
1696 | * If we hit an ENOENT here it means that the | |
1697 | * allocation was insufficient which is a bug. | |
1698 | */ | |
1699 | BUG_ON(lcn == LCN_ENOENT); | |
1700 | ||
1701 | /* It is a hole, need to instantiate it. */ | |
1702 | if (lcn == LCN_HOLE) { | |
1703 | // TODO: Instantiate the hole. | |
1704 | // clear_buffer_new(bh); | |
1705 | // unmap_underlying_metadata(bh->b_bdev, | |
1706 | // bh->b_blocknr); | |
1707 | // For non-uptodate buffers, need to | |
1708 | // zero out the region outside the | |
1709 | // request in this bh or all bhs, | |
1710 | // depending on what we implemented | |
1711 | // above. | |
1712 | // Need to flush_dcache_page(). | |
1713 | // Or could use set_buffer_new() | |
1714 | // instead? | |
1715 | ntfs_error(vol->sb, "Writing into " | |
1716 | "sparse regions is " | |
1717 | "not supported yet. " | |
1718 | "Sorry."); | |
1719 | err = -EOPNOTSUPP; | |
9f993fe4 AA |
1720 | if (!rl) |
1721 | up_read(&ni->runlist.lock); | |
1da177e4 LT |
1722 | goto err_out; |
1723 | } else if (!is_retry && | |
1724 | lcn == LCN_RL_NOT_MAPPED) { | |
1725 | is_retry = TRUE; | |
1726 | /* | |
1727 | * Attempt to map runlist, dropping | |
1728 | * lock for the duration. | |
1729 | */ | |
1730 | up_read(&ni->runlist.lock); | |
1731 | err = ntfs_map_runlist(ni, vcn); | |
1732 | if (likely(!err)) | |
1733 | goto lock_retry_remap; | |
1734 | rl = NULL; | |
9f993fe4 AA |
1735 | } else if (!rl) |
1736 | up_read(&ni->runlist.lock); | |
1da177e4 LT |
1737 | /* |
1738 | * Failed to map the buffer, even after | |
1739 | * retrying. | |
1740 | */ | |
7d333d6c AA |
1741 | if (!err) |
1742 | err = -EIO; | |
1da177e4 LT |
1743 | bh->b_blocknr = -1; |
1744 | ntfs_error(vol->sb, "Failed to write to inode " | |
1745 | "0x%lx, attribute type 0x%x, " | |
1746 | "vcn 0x%llx, offset 0x%x " | |
1747 | "because its location on disk " | |
1748 | "could not be determined%s " | |
7d333d6c | 1749 | "(error code %i).", |
1da177e4 LT |
1750 | ni->mft_no, ni->type, |
1751 | (unsigned long long)vcn, | |
1752 | vcn_ofs, is_retry ? " even " | |
7d333d6c | 1753 | "after retrying" : "", err); |
1da177e4 LT |
1754 | goto err_out; |
1755 | } | |
1756 | /* We now have a successful remap, i.e. lcn >= 0. */ | |
1757 | ||
1758 | /* Setup buffer head to correct block. */ | |
1759 | bh->b_blocknr = ((lcn << vol->cluster_size_bits) | |
1760 | + vcn_ofs) >> blocksize_bits; | |
1761 | set_buffer_mapped(bh); | |
1762 | ||
1763 | // FIXME: Something analogous to this is needed for | |
1764 | // each newly allocated block, i.e. BH_New. | |
1765 | // FIXME: Might need to take this out of the | |
1766 | // if (!buffer_mapped(bh)) {}, depending on how we | |
1767 | // implement things during the allocated_size and | |
1768 | // initialized_size extension code above. | |
1769 | if (buffer_new(bh)) { | |
1770 | clear_buffer_new(bh); | |
1771 | unmap_underlying_metadata(bh->b_bdev, | |
1772 | bh->b_blocknr); | |
1773 | if (PageUptodate(page)) { | |
1774 | set_buffer_uptodate(bh); | |
1775 | continue; | |
1776 | } | |
1777 | /* | |
1778 | * Page is _not_ uptodate, zero surrounding | |
1779 | * region. NOTE: This is how we decide if to | |
1780 | * zero or not! | |
1781 | */ | |
1782 | if (block_end > to || block_start < from) { | |
1783 | void *kaddr; | |
1784 | ||
1785 | kaddr = kmap_atomic(page, KM_USER0); | |
1786 | if (block_end > to) | |
1787 | memset(kaddr + to, 0, | |
1788 | block_end - to); | |
1789 | if (block_start < from) | |
1790 | memset(kaddr + block_start, 0, | |
1791 | from - | |
1792 | block_start); | |
1793 | flush_dcache_page(page); | |
1794 | kunmap_atomic(kaddr, KM_USER0); | |
1795 | } | |
1796 | continue; | |
1797 | } | |
1798 | } | |
1799 | /* @bh is mapped, set it uptodate if the page is uptodate. */ | |
1800 | if (PageUptodate(page)) { | |
1801 | if (!buffer_uptodate(bh)) | |
1802 | set_buffer_uptodate(bh); | |
1803 | continue; | |
1804 | } | |
1805 | /* | |
1806 | * The page is not uptodate. The buffer is mapped. If it is not | |
1807 | * uptodate, and it is only partially being written to, we need | |
1808 | * to read the buffer in before the write, i.e. right now. | |
1809 | */ | |
1810 | if (!buffer_uptodate(bh) && | |
1811 | (block_start < from || block_end > to)) { | |
1812 | ll_rw_block(READ, 1, &bh); | |
1813 | *wait_bh++ = bh; | |
1814 | } | |
1815 | } while (block++, block_start = block_end, | |
1816 | (bh = bh->b_this_page) != head); | |
1817 | ||
1818 | /* Release the lock if we took it. */ | |
1819 | if (rl) { | |
1820 | up_read(&ni->runlist.lock); | |
1821 | rl = NULL; | |
1822 | } | |
1823 | ||
1824 | /* If we issued read requests, let them complete. */ | |
1825 | while (wait_bh > wait) { | |
1826 | wait_on_buffer(*--wait_bh); | |
1827 | if (!buffer_uptodate(*wait_bh)) | |
1828 | return -EIO; | |
1829 | } | |
1830 | ||
1831 | ntfs_debug("Done."); | |
1832 | return 0; | |
1833 | err_out: | |
1834 | /* | |
1835 | * Zero out any newly allocated blocks to avoid exposing stale data. | |
1836 | * If BH_New is set, we know that the block was newly allocated in the | |
1837 | * above loop. | |
1838 | * FIXME: What about initialized_size increments? Have we done all the | |
1839 | * required zeroing above? If not this error handling is broken, and | |
1840 | * in particular the if (block_end <= from) check is completely bogus. | |
1841 | */ | |
1842 | bh = head; | |
1843 | block_start = 0; | |
1844 | is_retry = FALSE; | |
1845 | do { | |
1846 | block_end = block_start + blocksize; | |
1847 | if (block_end <= from) | |
1848 | continue; | |
1849 | if (block_start >= to) | |
1850 | break; | |
1851 | if (buffer_new(bh)) { | |
1852 | void *kaddr; | |
1853 | ||
1854 | clear_buffer_new(bh); | |
1855 | kaddr = kmap_atomic(page, KM_USER0); | |
1856 | memset(kaddr + block_start, 0, bh->b_size); | |
1857 | kunmap_atomic(kaddr, KM_USER0); | |
1858 | set_buffer_uptodate(bh); | |
1859 | mark_buffer_dirty(bh); | |
1860 | is_retry = TRUE; | |
1861 | } | |
1862 | } while (block_start = block_end, (bh = bh->b_this_page) != head); | |
1863 | if (is_retry) | |
1864 | flush_dcache_page(page); | |
1865 | if (rl) | |
1866 | up_read(&ni->runlist.lock); | |
1867 | return err; | |
1868 | } | |
1869 | ||
1870 | /** | |
1871 | * ntfs_prepare_write - prepare a page for receiving data | |
1872 | * | |
1873 | * This is called from generic_file_write() with i_sem held on the inode | |
1874 | * (@page->mapping->host). The @page is locked but not kmap()ped. The source | |
1875 | * data has not yet been copied into the @page. | |
1876 | * | |
1877 | * Need to extend the attribute/fill in holes if necessary, create blocks and | |
1878 | * make partially overwritten blocks uptodate, | |
1879 | * | |
1880 | * i_size is not to be modified yet. | |
1881 | * | |
1882 | * Return 0 on success or -errno on error. | |
1883 | * | |
1884 | * Should be using block_prepare_write() [support for sparse files] or | |
1885 | * cont_prepare_write() [no support for sparse files]. Cannot do that due to | |
1886 | * ntfs specifics but can look at them for implementation guidance. | |
1887 | * | |
1888 | * Note: In the range, @from is inclusive and @to is exclusive, i.e. @from is | |
1889 | * the first byte in the page that will be written to and @to is the first byte | |
1890 | * after the last byte that will be written to. | |
1891 | */ | |
1892 | static int ntfs_prepare_write(struct file *file, struct page *page, | |
1893 | unsigned from, unsigned to) | |
1894 | { | |
1895 | s64 new_size; | |
f40661be | 1896 | loff_t i_size; |
1da177e4 LT |
1897 | struct inode *vi = page->mapping->host; |
1898 | ntfs_inode *base_ni = NULL, *ni = NTFS_I(vi); | |
1899 | ntfs_volume *vol = ni->vol; | |
1900 | ntfs_attr_search_ctx *ctx = NULL; | |
1901 | MFT_RECORD *m = NULL; | |
1902 | ATTR_RECORD *a; | |
1903 | u8 *kaddr; | |
1904 | u32 attr_len; | |
1905 | int err; | |
1906 | ||
1907 | ntfs_debug("Entering for inode 0x%lx, attribute type 0x%x, page index " | |
1908 | "0x%lx, from = %u, to = %u.", vi->i_ino, ni->type, | |
1909 | page->index, from, to); | |
1910 | BUG_ON(!PageLocked(page)); | |
1911 | BUG_ON(from > PAGE_CACHE_SIZE); | |
1912 | BUG_ON(to > PAGE_CACHE_SIZE); | |
1913 | BUG_ON(from > to); | |
1914 | BUG_ON(NInoMstProtected(ni)); | |
1915 | /* | |
1916 | * If a previous ntfs_truncate() failed, repeat it and abort if it | |
1917 | * fails again. | |
1918 | */ | |
1919 | if (unlikely(NInoTruncateFailed(ni))) { | |
1920 | down_write(&vi->i_alloc_sem); | |
1921 | err = ntfs_truncate(vi); | |
1922 | up_write(&vi->i_alloc_sem); | |
1923 | if (err || NInoTruncateFailed(ni)) { | |
1924 | if (!err) | |
1925 | err = -EIO; | |
1926 | goto err_out; | |
1927 | } | |
1928 | } | |
1929 | /* If the attribute is not resident, deal with it elsewhere. */ | |
1930 | if (NInoNonResident(ni)) { | |
1931 | /* | |
1932 | * Only unnamed $DATA attributes can be compressed, encrypted, | |
1933 | * and/or sparse. | |
1934 | */ | |
1935 | if (ni->type == AT_DATA && !ni->name_len) { | |
1936 | /* If file is encrypted, deny access, just like NT4. */ | |
1937 | if (NInoEncrypted(ni)) { | |
1938 | ntfs_debug("Denying write access to encrypted " | |
1939 | "file."); | |
1940 | return -EACCES; | |
1941 | } | |
1942 | /* Compressed data streams are handled in compress.c. */ | |
1943 | if (NInoCompressed(ni)) { | |
1944 | // TODO: Implement and replace this check with | |
1945 | // return ntfs_write_compressed_block(page); | |
1946 | ntfs_error(vi->i_sb, "Writing to compressed " | |
1947 | "files is not supported yet. " | |
1948 | "Sorry."); | |
1949 | return -EOPNOTSUPP; | |
1950 | } | |
1951 | // TODO: Implement and remove this check. | |
1952 | if (NInoSparse(ni)) { | |
1953 | ntfs_error(vi->i_sb, "Writing to sparse files " | |
1954 | "is not supported yet. Sorry."); | |
1955 | return -EOPNOTSUPP; | |
1956 | } | |
1957 | } | |
1958 | /* Normal data stream. */ | |
1959 | return ntfs_prepare_nonresident_write(page, from, to); | |
1960 | } | |
1961 | /* | |
1962 | * Attribute is resident, implying it is not compressed, encrypted, or | |
1963 | * sparse. | |
1964 | */ | |
1965 | BUG_ON(page_has_buffers(page)); | |
1966 | new_size = ((s64)page->index << PAGE_CACHE_SHIFT) + to; | |
1967 | /* If we do not need to resize the attribute allocation we are done. */ | |
07a4e2da | 1968 | if (new_size <= i_size_read(vi)) |
1da177e4 | 1969 | goto done; |
1da177e4 LT |
1970 | /* Map, pin, and lock the (base) mft record. */ |
1971 | if (!NInoAttr(ni)) | |
1972 | base_ni = ni; | |
1973 | else | |
1974 | base_ni = ni->ext.base_ntfs_ino; | |
1975 | m = map_mft_record(base_ni); | |
1976 | if (IS_ERR(m)) { | |
1977 | err = PTR_ERR(m); | |
1978 | m = NULL; | |
1979 | ctx = NULL; | |
1980 | goto err_out; | |
1981 | } | |
1982 | ctx = ntfs_attr_get_search_ctx(base_ni, m); | |
1983 | if (unlikely(!ctx)) { | |
1984 | err = -ENOMEM; | |
1985 | goto err_out; | |
1986 | } | |
1987 | err = ntfs_attr_lookup(ni->type, ni->name, ni->name_len, | |
1988 | CASE_SENSITIVE, 0, NULL, 0, ctx); | |
1989 | if (unlikely(err)) { | |
1990 | if (err == -ENOENT) | |
1991 | err = -EIO; | |
1992 | goto err_out; | |
1993 | } | |
1994 | m = ctx->mrec; | |
1995 | a = ctx->attr; | |
1996 | /* The total length of the attribute value. */ | |
1997 | attr_len = le32_to_cpu(a->data.resident.value_length); | |
946929d8 | 1998 | /* Fix an eventual previous failure of ntfs_commit_write(). */ |
f40661be AA |
1999 | i_size = i_size_read(vi); |
2000 | if (unlikely(attr_len > i_size)) { | |
2001 | attr_len = i_size; | |
946929d8 | 2002 | a->data.resident.value_length = cpu_to_le32(attr_len); |
946929d8 | 2003 | } |
946929d8 AA |
2004 | /* If we do not need to resize the attribute allocation we are done. */ |
2005 | if (new_size <= attr_len) | |
2006 | goto done_unm; | |
1da177e4 LT |
2007 | /* Check if new size is allowed in $AttrDef. */ |
2008 | err = ntfs_attr_size_bounds_check(vol, ni->type, new_size); | |
2009 | if (unlikely(err)) { | |
2010 | if (err == -ERANGE) { | |
2011 | ntfs_error(vol->sb, "Write would cause the inode " | |
2012 | "0x%lx to exceed the maximum size for " | |
2013 | "its attribute type (0x%x). Aborting " | |
2014 | "write.", vi->i_ino, | |
2015 | le32_to_cpu(ni->type)); | |
2016 | } else { | |
2017 | ntfs_error(vol->sb, "Inode 0x%lx has unknown " | |
2018 | "attribute type 0x%x. Aborting " | |
2019 | "write.", vi->i_ino, | |
2020 | le32_to_cpu(ni->type)); | |
2021 | err = -EIO; | |
2022 | } | |
2023 | goto err_out2; | |
2024 | } | |
2025 | /* | |
2026 | * Extend the attribute record to be able to store the new attribute | |
2027 | * size. | |
2028 | */ | |
2029 | if (new_size >= vol->mft_record_size || ntfs_attr_record_resize(m, a, | |
2030 | le16_to_cpu(a->data.resident.value_offset) + | |
2031 | new_size)) { | |
2032 | /* Not enough space in the mft record. */ | |
2033 | ntfs_error(vol->sb, "Not enough space in the mft record for " | |
2034 | "the resized attribute value. This is not " | |
2035 | "supported yet. Aborting write."); | |
2036 | err = -EOPNOTSUPP; | |
2037 | goto err_out2; | |
2038 | } | |
2039 | /* | |
2040 | * We have enough space in the mft record to fit the write. This | |
2041 | * implies the attribute is smaller than the mft record and hence the | |
2042 | * attribute must be in a single page and hence page->index must be 0. | |
2043 | */ | |
2044 | BUG_ON(page->index); | |
2045 | /* | |
2046 | * If the beginning of the write is past the old size, enlarge the | |
2047 | * attribute value up to the beginning of the write and fill it with | |
2048 | * zeroes. | |
2049 | */ | |
2050 | if (from > attr_len) { | |
2051 | memset((u8*)a + le16_to_cpu(a->data.resident.value_offset) + | |
2052 | attr_len, 0, from - attr_len); | |
2053 | a->data.resident.value_length = cpu_to_le32(from); | |
2054 | /* Zero the corresponding area in the page as well. */ | |
2055 | if (PageUptodate(page)) { | |
2056 | kaddr = kmap_atomic(page, KM_USER0); | |
2057 | memset(kaddr + attr_len, 0, from - attr_len); | |
2058 | kunmap_atomic(kaddr, KM_USER0); | |
2059 | flush_dcache_page(page); | |
2060 | } | |
2061 | } | |
2062 | flush_dcache_mft_record_page(ctx->ntfs_ino); | |
2063 | mark_mft_record_dirty(ctx->ntfs_ino); | |
946929d8 | 2064 | done_unm: |
1da177e4 LT |
2065 | ntfs_attr_put_search_ctx(ctx); |
2066 | unmap_mft_record(base_ni); | |
2067 | /* | |
2068 | * Because resident attributes are handled by memcpy() to/from the | |
2069 | * corresponding MFT record, and because this form of i/o is byte | |
2070 | * aligned rather than block aligned, there is no need to bring the | |
2071 | * page uptodate here as in the non-resident case where we need to | |
2072 | * bring the buffers straddled by the write uptodate before | |
2073 | * generic_file_write() does the copying from userspace. | |
2074 | * | |
2075 | * We thus defer the uptodate bringing of the page region outside the | |
2076 | * region written to to ntfs_commit_write(), which makes the code | |
2077 | * simpler and saves one atomic kmap which is good. | |
2078 | */ | |
2079 | done: | |
2080 | ntfs_debug("Done."); | |
2081 | return 0; | |
2082 | err_out: | |
2083 | if (err == -ENOMEM) | |
2084 | ntfs_warning(vi->i_sb, "Error allocating memory required to " | |
2085 | "prepare the write."); | |
2086 | else { | |
2087 | ntfs_error(vi->i_sb, "Resident attribute prepare write failed " | |
2088 | "with error %i.", err); | |
2089 | NVolSetErrors(vol); | |
2090 | make_bad_inode(vi); | |
2091 | } | |
2092 | err_out2: | |
2093 | if (ctx) | |
2094 | ntfs_attr_put_search_ctx(ctx); | |
2095 | if (m) | |
2096 | unmap_mft_record(base_ni); | |
2097 | return err; | |
2098 | } | |
2099 | ||
2100 | /** | |
2101 | * ntfs_commit_nonresident_write - | |
2102 | * | |
2103 | */ | |
2104 | static int ntfs_commit_nonresident_write(struct page *page, | |
2105 | unsigned from, unsigned to) | |
2106 | { | |
2107 | s64 pos = ((s64)page->index << PAGE_CACHE_SHIFT) + to; | |
2108 | struct inode *vi = page->mapping->host; | |
2109 | struct buffer_head *bh, *head; | |
2110 | unsigned int block_start, block_end, blocksize; | |
2111 | BOOL partial; | |
2112 | ||
2113 | ntfs_debug("Entering for inode 0x%lx, attribute type 0x%x, page index " | |
2114 | "0x%lx, from = %u, to = %u.", vi->i_ino, | |
2115 | NTFS_I(vi)->type, page->index, from, to); | |
2116 | blocksize = 1 << vi->i_blkbits; | |
2117 | ||
2118 | // FIXME: We need a whole slew of special cases in here for compressed | |
2119 | // files for example... | |
2120 | // For now, we know ntfs_prepare_write() would have failed so we can't | |
2121 | // get here in any of the cases which we have to special case, so we | |
2122 | // are just a ripped off, unrolled generic_commit_write(). | |
2123 | ||
2124 | bh = head = page_buffers(page); | |
2125 | block_start = 0; | |
2126 | partial = FALSE; | |
2127 | do { | |
2128 | block_end = block_start + blocksize; | |
2129 | if (block_end <= from || block_start >= to) { | |
2130 | if (!buffer_uptodate(bh)) | |
2131 | partial = TRUE; | |
2132 | } else { | |
2133 | set_buffer_uptodate(bh); | |
2134 | mark_buffer_dirty(bh); | |
2135 | } | |
2136 | } while (block_start = block_end, (bh = bh->b_this_page) != head); | |
2137 | /* | |
2138 | * If this is a partial write which happened to make all buffers | |
2139 | * uptodate then we can optimize away a bogus ->readpage() for the next | |
2140 | * read(). Here we 'discover' whether the page went uptodate as a | |
2141 | * result of this (potentially partial) write. | |
2142 | */ | |
2143 | if (!partial) | |
2144 | SetPageUptodate(page); | |
2145 | /* | |
2146 | * Not convinced about this at all. See disparity comment above. For | |
2147 | * now we know ntfs_prepare_write() would have failed in the write | |
2148 | * exceeds i_size case, so this will never trigger which is fine. | |
2149 | */ | |
07a4e2da | 2150 | if (pos > i_size_read(vi)) { |
1da177e4 LT |
2151 | ntfs_error(vi->i_sb, "Writing beyond the existing file size is " |
2152 | "not supported yet. Sorry."); | |
2153 | return -EOPNOTSUPP; | |
2154 | // vi->i_size = pos; | |
2155 | // mark_inode_dirty(vi); | |
2156 | } | |
2157 | ntfs_debug("Done."); | |
2158 | return 0; | |
2159 | } | |
2160 | ||
2161 | /** | |
2162 | * ntfs_commit_write - commit the received data | |
2163 | * | |
2164 | * This is called from generic_file_write() with i_sem held on the inode | |
2165 | * (@page->mapping->host). The @page is locked but not kmap()ped. The source | |
2166 | * data has already been copied into the @page. ntfs_prepare_write() has been | |
2167 | * called before the data copied and it returned success so we can take the | |
2168 | * results of various BUG checks and some error handling for granted. | |
2169 | * | |
2170 | * Need to mark modified blocks dirty so they get written out later when | |
2171 | * ntfs_writepage() is invoked by the VM. | |
2172 | * | |
2173 | * Return 0 on success or -errno on error. | |
2174 | * | |
2175 | * Should be using generic_commit_write(). This marks buffers uptodate and | |
2176 | * dirty, sets the page uptodate if all buffers in the page are uptodate, and | |
2177 | * updates i_size if the end of io is beyond i_size. In that case, it also | |
2178 | * marks the inode dirty. | |
2179 | * | |
2180 | * Cannot use generic_commit_write() due to ntfs specialities but can look at | |
2181 | * it for implementation guidance. | |
2182 | * | |
2183 | * If things have gone as outlined in ntfs_prepare_write(), then we do not | |
2184 | * need to do any page content modifications here at all, except in the write | |
2185 | * to resident attribute case, where we need to do the uptodate bringing here | |
2186 | * which we combine with the copying into the mft record which means we save | |
2187 | * one atomic kmap. | |
2188 | */ | |
2189 | static int ntfs_commit_write(struct file *file, struct page *page, | |
2190 | unsigned from, unsigned to) | |
2191 | { | |
2192 | struct inode *vi = page->mapping->host; | |
2193 | ntfs_inode *base_ni, *ni = NTFS_I(vi); | |
2194 | char *kaddr, *kattr; | |
2195 | ntfs_attr_search_ctx *ctx; | |
2196 | MFT_RECORD *m; | |
2197 | ATTR_RECORD *a; | |
2198 | u32 attr_len; | |
2199 | int err; | |
2200 | ||
2201 | ntfs_debug("Entering for inode 0x%lx, attribute type 0x%x, page index " | |
2202 | "0x%lx, from = %u, to = %u.", vi->i_ino, ni->type, | |
2203 | page->index, from, to); | |
2204 | /* If the attribute is not resident, deal with it elsewhere. */ | |
2205 | if (NInoNonResident(ni)) { | |
2206 | /* Only unnamed $DATA attributes can be compressed/encrypted. */ | |
2207 | if (ni->type == AT_DATA && !ni->name_len) { | |
2208 | /* Encrypted files need separate handling. */ | |
2209 | if (NInoEncrypted(ni)) { | |
2210 | // We never get here at present! | |
2211 | BUG(); | |
2212 | } | |
2213 | /* Compressed data streams are handled in compress.c. */ | |
2214 | if (NInoCompressed(ni)) { | |
2215 | // TODO: Implement this! | |
2216 | // return ntfs_write_compressed_block(page); | |
2217 | // We never get here at present! | |
2218 | BUG(); | |
2219 | } | |
2220 | } | |
2221 | /* Normal data stream. */ | |
2222 | return ntfs_commit_nonresident_write(page, from, to); | |
2223 | } | |
2224 | /* | |
2225 | * Attribute is resident, implying it is not compressed, encrypted, or | |
2226 | * sparse. | |
2227 | */ | |
2228 | if (!NInoAttr(ni)) | |
2229 | base_ni = ni; | |
2230 | else | |
2231 | base_ni = ni->ext.base_ntfs_ino; | |
2232 | /* Map, pin, and lock the mft record. */ | |
2233 | m = map_mft_record(base_ni); | |
2234 | if (IS_ERR(m)) { | |
2235 | err = PTR_ERR(m); | |
2236 | m = NULL; | |
2237 | ctx = NULL; | |
2238 | goto err_out; | |
2239 | } | |
2240 | ctx = ntfs_attr_get_search_ctx(base_ni, m); | |
2241 | if (unlikely(!ctx)) { | |
2242 | err = -ENOMEM; | |
2243 | goto err_out; | |
2244 | } | |
2245 | err = ntfs_attr_lookup(ni->type, ni->name, ni->name_len, | |
2246 | CASE_SENSITIVE, 0, NULL, 0, ctx); | |
2247 | if (unlikely(err)) { | |
2248 | if (err == -ENOENT) | |
2249 | err = -EIO; | |
2250 | goto err_out; | |
2251 | } | |
2252 | a = ctx->attr; | |
2253 | /* The total length of the attribute value. */ | |
2254 | attr_len = le32_to_cpu(a->data.resident.value_length); | |
2255 | BUG_ON(from > attr_len); | |
2256 | kattr = (u8*)a + le16_to_cpu(a->data.resident.value_offset); | |
2257 | kaddr = kmap_atomic(page, KM_USER0); | |
2258 | /* Copy the received data from the page to the mft record. */ | |
2259 | memcpy(kattr + from, kaddr + from, to - from); | |
2260 | /* Update the attribute length if necessary. */ | |
2261 | if (to > attr_len) { | |
2262 | attr_len = to; | |
2263 | a->data.resident.value_length = cpu_to_le32(attr_len); | |
2264 | } | |
2265 | /* | |
2266 | * If the page is not uptodate, bring the out of bounds area(s) | |
2267 | * uptodate by copying data from the mft record to the page. | |
2268 | */ | |
2269 | if (!PageUptodate(page)) { | |
2270 | if (from > 0) | |
2271 | memcpy(kaddr, kattr, from); | |
2272 | if (to < attr_len) | |
2273 | memcpy(kaddr + to, kattr + to, attr_len - to); | |
2274 | /* Zero the region outside the end of the attribute value. */ | |
2275 | if (attr_len < PAGE_CACHE_SIZE) | |
2276 | memset(kaddr + attr_len, 0, PAGE_CACHE_SIZE - attr_len); | |
2277 | /* | |
2278 | * The probability of not having done any of the above is | |
2279 | * extremely small, so we just flush unconditionally. | |
2280 | */ | |
2281 | flush_dcache_page(page); | |
2282 | SetPageUptodate(page); | |
2283 | } | |
2284 | kunmap_atomic(kaddr, KM_USER0); | |
2285 | /* Update i_size if necessary. */ | |
07a4e2da AA |
2286 | if (i_size_read(vi) < attr_len) { |
2287 | unsigned long flags; | |
2288 | ||
2289 | write_lock_irqsave(&ni->size_lock, flags); | |
1da177e4 LT |
2290 | ni->allocated_size = ni->initialized_size = attr_len; |
2291 | i_size_write(vi, attr_len); | |
07a4e2da | 2292 | write_unlock_irqrestore(&ni->size_lock, flags); |
1da177e4 LT |
2293 | } |
2294 | /* Mark the mft record dirty, so it gets written back. */ | |
2295 | flush_dcache_mft_record_page(ctx->ntfs_ino); | |
2296 | mark_mft_record_dirty(ctx->ntfs_ino); | |
2297 | ntfs_attr_put_search_ctx(ctx); | |
2298 | unmap_mft_record(base_ni); | |
2299 | ntfs_debug("Done."); | |
2300 | return 0; | |
2301 | err_out: | |
2302 | if (err == -ENOMEM) { | |
2303 | ntfs_warning(vi->i_sb, "Error allocating memory required to " | |
2304 | "commit the write."); | |
2305 | if (PageUptodate(page)) { | |
2306 | ntfs_warning(vi->i_sb, "Page is uptodate, setting " | |
2307 | "dirty so the write will be retried " | |
2308 | "later on by the VM."); | |
2309 | /* | |
2310 | * Put the page on mapping->dirty_pages, but leave its | |
2311 | * buffers' dirty state as-is. | |
2312 | */ | |
2313 | __set_page_dirty_nobuffers(page); | |
2314 | err = 0; | |
2315 | } else | |
2316 | ntfs_error(vi->i_sb, "Page is not uptodate. Written " | |
2317 | "data has been lost."); | |
2318 | } else { | |
2319 | ntfs_error(vi->i_sb, "Resident attribute commit write failed " | |
2320 | "with error %i.", err); | |
2321 | NVolSetErrors(ni->vol); | |
2322 | make_bad_inode(vi); | |
2323 | } | |
2324 | if (ctx) | |
2325 | ntfs_attr_put_search_ctx(ctx); | |
2326 | if (m) | |
2327 | unmap_mft_record(base_ni); | |
2328 | return err; | |
2329 | } | |
2330 | ||
2331 | #endif /* NTFS_RW */ | |
2332 | ||
2333 | /** | |
2334 | * ntfs_aops - general address space operations for inodes and attributes | |
2335 | */ | |
2336 | struct address_space_operations ntfs_aops = { | |
2337 | .readpage = ntfs_readpage, /* Fill page with data. */ | |
2338 | .sync_page = block_sync_page, /* Currently, just unplugs the | |
2339 | disk request queue. */ | |
2340 | #ifdef NTFS_RW | |
2341 | .writepage = ntfs_writepage, /* Write dirty page to disk. */ | |
2342 | .prepare_write = ntfs_prepare_write, /* Prepare page and buffers | |
2343 | ready to receive data. */ | |
2344 | .commit_write = ntfs_commit_write, /* Commit received data. */ | |
2345 | #endif /* NTFS_RW */ | |
2346 | }; | |
2347 | ||
2348 | /** | |
2349 | * ntfs_mst_aops - general address space operations for mst protecteed inodes | |
2350 | * and attributes | |
2351 | */ | |
2352 | struct address_space_operations ntfs_mst_aops = { | |
2353 | .readpage = ntfs_readpage, /* Fill page with data. */ | |
2354 | .sync_page = block_sync_page, /* Currently, just unplugs the | |
2355 | disk request queue. */ | |
2356 | #ifdef NTFS_RW | |
2357 | .writepage = ntfs_writepage, /* Write dirty page to disk. */ | |
2358 | .set_page_dirty = __set_page_dirty_nobuffers, /* Set the page dirty | |
2359 | without touching the buffers | |
2360 | belonging to the page. */ | |
2361 | #endif /* NTFS_RW */ | |
2362 | }; | |
2363 | ||
2364 | #ifdef NTFS_RW | |
2365 | ||
2366 | /** | |
2367 | * mark_ntfs_record_dirty - mark an ntfs record dirty | |
2368 | * @page: page containing the ntfs record to mark dirty | |
2369 | * @ofs: byte offset within @page at which the ntfs record begins | |
2370 | * | |
2371 | * Set the buffers and the page in which the ntfs record is located dirty. | |
2372 | * | |
2373 | * The latter also marks the vfs inode the ntfs record belongs to dirty | |
2374 | * (I_DIRTY_PAGES only). | |
2375 | * | |
2376 | * If the page does not have buffers, we create them and set them uptodate. | |
2377 | * The page may not be locked which is why we need to handle the buffers under | |
2378 | * the mapping->private_lock. Once the buffers are marked dirty we no longer | |
2379 | * need the lock since try_to_free_buffers() does not free dirty buffers. | |
2380 | */ | |
2381 | void mark_ntfs_record_dirty(struct page *page, const unsigned int ofs) { | |
2382 | struct address_space *mapping = page->mapping; | |
2383 | ntfs_inode *ni = NTFS_I(mapping->host); | |
2384 | struct buffer_head *bh, *head, *buffers_to_free = NULL; | |
2385 | unsigned int end, bh_size, bh_ofs; | |
2386 | ||
2387 | BUG_ON(!PageUptodate(page)); | |
2388 | end = ofs + ni->itype.index.block_size; | |
2389 | bh_size = 1 << VFS_I(ni)->i_blkbits; | |
2390 | spin_lock(&mapping->private_lock); | |
2391 | if (unlikely(!page_has_buffers(page))) { | |
2392 | spin_unlock(&mapping->private_lock); | |
2393 | bh = head = alloc_page_buffers(page, bh_size, 1); | |
2394 | spin_lock(&mapping->private_lock); | |
2395 | if (likely(!page_has_buffers(page))) { | |
2396 | struct buffer_head *tail; | |
2397 | ||
2398 | do { | |
2399 | set_buffer_uptodate(bh); | |
2400 | tail = bh; | |
2401 | bh = bh->b_this_page; | |
2402 | } while (bh); | |
2403 | tail->b_this_page = head; | |
2404 | attach_page_buffers(page, head); | |
2405 | } else | |
2406 | buffers_to_free = bh; | |
2407 | } | |
2408 | bh = head = page_buffers(page); | |
a01ac532 | 2409 | BUG_ON(!bh); |
1da177e4 LT |
2410 | do { |
2411 | bh_ofs = bh_offset(bh); | |
2412 | if (bh_ofs + bh_size <= ofs) | |
2413 | continue; | |
2414 | if (unlikely(bh_ofs >= end)) | |
2415 | break; | |
2416 | set_buffer_dirty(bh); | |
2417 | } while ((bh = bh->b_this_page) != head); | |
2418 | spin_unlock(&mapping->private_lock); | |
2419 | __set_page_dirty_nobuffers(page); | |
2420 | if (unlikely(buffers_to_free)) { | |
2421 | do { | |
2422 | bh = buffers_to_free->b_this_page; | |
2423 | free_buffer_head(buffers_to_free); | |
2424 | buffers_to_free = bh; | |
2425 | } while (buffers_to_free); | |
2426 | } | |
2427 | } | |
2428 | ||
2429 | #endif /* NTFS_RW */ |