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