blob: 7275338918132fe31eed51bddf2d48485d52c1b9 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
Anton Altaparmakovf25dfb52005-09-08 20:35:33 +01002 * file.c - NTFS kernel file operations. Part of the Linux-NTFS project.
Linus Torvalds1da177e2005-04-16 15:20:36 -07003 *
Anton Altaparmakovf25dfb52005-09-08 20:35:33 +01004 * Copyright (c) 2001-2005 Anton Altaparmakov
Linus Torvalds1da177e2005-04-16 15:20:36 -07005 *
6 * This program/include file is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License as published
8 * by the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 *
11 * This program/include file is distributed in the hope that it will be
12 * useful, but WITHOUT ANY WARRANTY; without even the implied warranty
13 * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program (in the main directory of the Linux-NTFS
18 * distribution in the file COPYING); if not, write to the Free Software
19 * Foundation,Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
20 */
21
Linus Torvalds1da177e2005-04-16 15:20:36 -070022#include <linux/buffer_head.h>
Anton Altaparmakov98b27032005-10-11 15:40:40 +010023#include <linux/pagemap.h>
24#include <linux/pagevec.h>
25#include <linux/sched.h>
26#include <linux/swap.h>
27#include <linux/uio.h>
28#include <linux/writeback.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070029
Anton Altaparmakov98b27032005-10-11 15:40:40 +010030#include <asm/page.h>
31#include <asm/uaccess.h>
32
33#include "attrib.h"
34#include "bitmap.h"
Linus Torvalds1da177e2005-04-16 15:20:36 -070035#include "inode.h"
36#include "debug.h"
Anton Altaparmakov98b27032005-10-11 15:40:40 +010037#include "lcnalloc.h"
38#include "malloc.h"
39#include "mft.h"
Linus Torvalds1da177e2005-04-16 15:20:36 -070040#include "ntfs.h"
41
42/**
43 * ntfs_file_open - called when an inode is about to be opened
44 * @vi: inode to be opened
45 * @filp: file structure describing the inode
46 *
47 * Limit file size to the page cache limit on architectures where unsigned long
48 * is 32-bits. This is the most we can do for now without overflowing the page
49 * cache page index. Doing it this way means we don't run into problems because
50 * of existing too large files. It would be better to allow the user to read
51 * the beginning of the file but I doubt very much anyone is going to hit this
52 * check on a 32-bit architecture, so there is no point in adding the extra
53 * complexity required to support this.
54 *
55 * On 64-bit architectures, the check is hopefully optimized away by the
56 * compiler.
57 *
58 * After the check passes, just call generic_file_open() to do its work.
59 */
60static int ntfs_file_open(struct inode *vi, struct file *filp)
61{
62 if (sizeof(unsigned long) < 8) {
Anton Altaparmakovd4b9ba72004-11-17 15:45:08 +000063 if (i_size_read(vi) > MAX_LFS_FILESIZE)
Linus Torvalds1da177e2005-04-16 15:20:36 -070064 return -EFBIG;
65 }
66 return generic_file_open(vi, filp);
67}
68
69#ifdef NTFS_RW
70
71/**
Anton Altaparmakov98b27032005-10-11 15:40:40 +010072 * ntfs_attr_extend_initialized - extend the initialized size of an attribute
73 * @ni: ntfs inode of the attribute to extend
74 * @new_init_size: requested new initialized size in bytes
75 * @cached_page: store any allocated but unused page here
76 * @lru_pvec: lru-buffering pagevec of the caller
77 *
78 * Extend the initialized size of an attribute described by the ntfs inode @ni
79 * to @new_init_size bytes. This involves zeroing any non-sparse space between
80 * the old initialized size and @new_init_size both in the page cache and on
Anton Altaparmakovdda65b92005-10-24 08:57:59 +010081 * disk (if relevant complete pages are already uptodate in the page cache then
82 * these are simply marked dirty).
Anton Altaparmakov98b27032005-10-11 15:40:40 +010083 *
84 * As a side-effect, the file size (vfs inode->i_size) may be incremented as,
85 * in the resident attribute case, it is tied to the initialized size and, in
86 * the non-resident attribute case, it may not fall below the initialized size.
87 *
88 * Note that if the attribute is resident, we do not need to touch the page
89 * cache at all. This is because if the page cache page is not uptodate we
90 * bring it uptodate later, when doing the write to the mft record since we
91 * then already have the page mapped. And if the page is uptodate, the
92 * non-initialized region will already have been zeroed when the page was
93 * brought uptodate and the region may in fact already have been overwritten
94 * with new data via mmap() based writes, so we cannot just zero it. And since
95 * POSIX specifies that the behaviour of resizing a file whilst it is mmap()ped
96 * is unspecified, we choose not to do zeroing and thus we do not need to touch
Anton Altaparmakovdda65b92005-10-24 08:57:59 +010097 * the page at all. For a more detailed explanation see ntfs_truncate() in
98 * fs/ntfs/inode.c.
Anton Altaparmakov98b27032005-10-11 15:40:40 +010099 *
Anton Altaparmakovdda65b92005-10-24 08:57:59 +0100100 * @cached_page and @lru_pvec are just optimizations for dealing with multiple
Anton Altaparmakov98b27032005-10-11 15:40:40 +0100101 * pages.
102 *
103 * Return 0 on success and -errno on error. In the case that an error is
104 * encountered it is possible that the initialized size will already have been
105 * incremented some way towards @new_init_size but it is guaranteed that if
106 * this is the case, the necessary zeroing will also have happened and that all
107 * metadata is self-consistent.
108 *
Anton Altaparmakovdda65b92005-10-24 08:57:59 +0100109 * Locking: i_sem on the vfs inode corrseponsind to the ntfs inode @ni must be
110 * held by the caller.
Anton Altaparmakov98b27032005-10-11 15:40:40 +0100111 */
112static int ntfs_attr_extend_initialized(ntfs_inode *ni, const s64 new_init_size,
113 struct page **cached_page, struct pagevec *lru_pvec)
114{
115 s64 old_init_size;
116 loff_t old_i_size;
117 pgoff_t index, end_index;
118 unsigned long flags;
119 struct inode *vi = VFS_I(ni);
120 ntfs_inode *base_ni;
121 MFT_RECORD *m = NULL;
122 ATTR_RECORD *a;
123 ntfs_attr_search_ctx *ctx = NULL;
124 struct address_space *mapping;
125 struct page *page = NULL;
126 u8 *kattr;
127 int err;
128 u32 attr_len;
129
130 read_lock_irqsave(&ni->size_lock, flags);
131 old_init_size = ni->initialized_size;
132 old_i_size = i_size_read(vi);
133 BUG_ON(new_init_size > ni->allocated_size);
134 read_unlock_irqrestore(&ni->size_lock, flags);
135 ntfs_debug("Entering for i_ino 0x%lx, attribute type 0x%x, "
136 "old_initialized_size 0x%llx, "
137 "new_initialized_size 0x%llx, i_size 0x%llx.",
138 vi->i_ino, (unsigned)le32_to_cpu(ni->type),
139 (unsigned long long)old_init_size,
140 (unsigned long long)new_init_size, old_i_size);
141 if (!NInoAttr(ni))
142 base_ni = ni;
143 else
144 base_ni = ni->ext.base_ntfs_ino;
145 /* Use goto to reduce indentation and we need the label below anyway. */
146 if (NInoNonResident(ni))
147 goto do_non_resident_extend;
148 BUG_ON(old_init_size != old_i_size);
149 m = map_mft_record(base_ni);
150 if (IS_ERR(m)) {
151 err = PTR_ERR(m);
152 m = NULL;
153 goto err_out;
154 }
155 ctx = ntfs_attr_get_search_ctx(base_ni, m);
156 if (unlikely(!ctx)) {
157 err = -ENOMEM;
158 goto err_out;
159 }
160 err = ntfs_attr_lookup(ni->type, ni->name, ni->name_len,
161 CASE_SENSITIVE, 0, NULL, 0, ctx);
162 if (unlikely(err)) {
163 if (err == -ENOENT)
164 err = -EIO;
165 goto err_out;
166 }
167 m = ctx->mrec;
168 a = ctx->attr;
169 BUG_ON(a->non_resident);
170 /* The total length of the attribute value. */
171 attr_len = le32_to_cpu(a->data.resident.value_length);
172 BUG_ON(old_i_size != (loff_t)attr_len);
173 /*
174 * Do the zeroing in the mft record and update the attribute size in
175 * the mft record.
176 */
177 kattr = (u8*)a + le16_to_cpu(a->data.resident.value_offset);
178 memset(kattr + attr_len, 0, new_init_size - attr_len);
179 a->data.resident.value_length = cpu_to_le32((u32)new_init_size);
180 /* Finally, update the sizes in the vfs and ntfs inodes. */
181 write_lock_irqsave(&ni->size_lock, flags);
182 i_size_write(vi, new_init_size);
183 ni->initialized_size = new_init_size;
184 write_unlock_irqrestore(&ni->size_lock, flags);
185 goto done;
186do_non_resident_extend:
187 /*
188 * If the new initialized size @new_init_size exceeds the current file
189 * size (vfs inode->i_size), we need to extend the file size to the
190 * new initialized size.
191 */
192 if (new_init_size > old_i_size) {
193 m = map_mft_record(base_ni);
194 if (IS_ERR(m)) {
195 err = PTR_ERR(m);
196 m = NULL;
197 goto err_out;
198 }
199 ctx = ntfs_attr_get_search_ctx(base_ni, m);
200 if (unlikely(!ctx)) {
201 err = -ENOMEM;
202 goto err_out;
203 }
204 err = ntfs_attr_lookup(ni->type, ni->name, ni->name_len,
205 CASE_SENSITIVE, 0, NULL, 0, ctx);
206 if (unlikely(err)) {
207 if (err == -ENOENT)
208 err = -EIO;
209 goto err_out;
210 }
211 m = ctx->mrec;
212 a = ctx->attr;
213 BUG_ON(!a->non_resident);
214 BUG_ON(old_i_size != (loff_t)
215 sle64_to_cpu(a->data.non_resident.data_size));
216 a->data.non_resident.data_size = cpu_to_sle64(new_init_size);
217 flush_dcache_mft_record_page(ctx->ntfs_ino);
218 mark_mft_record_dirty(ctx->ntfs_ino);
219 /* Update the file size in the vfs inode. */
220 i_size_write(vi, new_init_size);
221 ntfs_attr_put_search_ctx(ctx);
222 ctx = NULL;
223 unmap_mft_record(base_ni);
224 m = NULL;
225 }
226 mapping = vi->i_mapping;
227 index = old_init_size >> PAGE_CACHE_SHIFT;
228 end_index = (new_init_size + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
229 do {
230 /*
231 * Read the page. If the page is not present, this will zero
232 * the uninitialized regions for us.
233 */
234 page = read_cache_page(mapping, index,
235 (filler_t*)mapping->a_ops->readpage, NULL);
236 if (IS_ERR(page)) {
237 err = PTR_ERR(page);
238 goto init_err_out;
239 }
240 wait_on_page_locked(page);
241 if (unlikely(!PageUptodate(page) || PageError(page))) {
242 page_cache_release(page);
243 err = -EIO;
244 goto init_err_out;
245 }
246 /*
247 * Update the initialized size in the ntfs inode. This is
248 * enough to make ntfs_writepage() work.
249 */
250 write_lock_irqsave(&ni->size_lock, flags);
251 ni->initialized_size = (index + 1) << PAGE_CACHE_SHIFT;
252 if (ni->initialized_size > new_init_size)
253 ni->initialized_size = new_init_size;
254 write_unlock_irqrestore(&ni->size_lock, flags);
255 /* Set the page dirty so it gets written out. */
256 set_page_dirty(page);
257 page_cache_release(page);
258 /*
259 * Play nice with the vm and the rest of the system. This is
260 * very much needed as we can potentially be modifying the
261 * initialised size from a very small value to a really huge
262 * value, e.g.
263 * f = open(somefile, O_TRUNC);
264 * truncate(f, 10GiB);
265 * seek(f, 10GiB);
266 * write(f, 1);
267 * And this would mean we would be marking dirty hundreds of
268 * thousands of pages or as in the above example more than
269 * two and a half million pages!
270 *
271 * TODO: For sparse pages could optimize this workload by using
272 * the FsMisc / MiscFs page bit as a "PageIsSparse" bit. This
273 * would be set in readpage for sparse pages and here we would
274 * not need to mark dirty any pages which have this bit set.
275 * The only caveat is that we have to clear the bit everywhere
276 * where we allocate any clusters that lie in the page or that
277 * contain the page.
278 *
279 * TODO: An even greater optimization would be for us to only
280 * call readpage() on pages which are not in sparse regions as
281 * determined from the runlist. This would greatly reduce the
282 * number of pages we read and make dirty in the case of sparse
283 * files.
284 */
285 balance_dirty_pages_ratelimited(mapping);
286 cond_resched();
287 } while (++index < end_index);
288 read_lock_irqsave(&ni->size_lock, flags);
289 BUG_ON(ni->initialized_size != new_init_size);
290 read_unlock_irqrestore(&ni->size_lock, flags);
291 /* Now bring in sync the initialized_size in the mft record. */
292 m = map_mft_record(base_ni);
293 if (IS_ERR(m)) {
294 err = PTR_ERR(m);
295 m = NULL;
296 goto init_err_out;
297 }
298 ctx = ntfs_attr_get_search_ctx(base_ni, m);
299 if (unlikely(!ctx)) {
300 err = -ENOMEM;
301 goto init_err_out;
302 }
303 err = ntfs_attr_lookup(ni->type, ni->name, ni->name_len,
304 CASE_SENSITIVE, 0, NULL, 0, ctx);
305 if (unlikely(err)) {
306 if (err == -ENOENT)
307 err = -EIO;
308 goto init_err_out;
309 }
310 m = ctx->mrec;
311 a = ctx->attr;
312 BUG_ON(!a->non_resident);
313 a->data.non_resident.initialized_size = cpu_to_sle64(new_init_size);
314done:
315 flush_dcache_mft_record_page(ctx->ntfs_ino);
316 mark_mft_record_dirty(ctx->ntfs_ino);
317 if (ctx)
318 ntfs_attr_put_search_ctx(ctx);
319 if (m)
320 unmap_mft_record(base_ni);
321 ntfs_debug("Done, initialized_size 0x%llx, i_size 0x%llx.",
322 (unsigned long long)new_init_size, i_size_read(vi));
323 return 0;
324init_err_out:
325 write_lock_irqsave(&ni->size_lock, flags);
326 ni->initialized_size = old_init_size;
327 write_unlock_irqrestore(&ni->size_lock, flags);
328err_out:
329 if (ctx)
330 ntfs_attr_put_search_ctx(ctx);
331 if (m)
332 unmap_mft_record(base_ni);
333 ntfs_debug("Failed. Returning error code %i.", err);
334 return err;
335}
336
337/**
338 * ntfs_fault_in_pages_readable -
339 *
340 * Fault a number of userspace pages into pagetables.
341 *
342 * Unlike include/linux/pagemap.h::fault_in_pages_readable(), this one copes
343 * with more than two userspace pages as well as handling the single page case
344 * elegantly.
345 *
346 * If you find this difficult to understand, then think of the while loop being
347 * the following code, except that we do without the integer variable ret:
348 *
349 * do {
350 * ret = __get_user(c, uaddr);
351 * uaddr += PAGE_SIZE;
352 * } while (!ret && uaddr < end);
353 *
354 * Note, the final __get_user() may well run out-of-bounds of the user buffer,
355 * but _not_ out-of-bounds of the page the user buffer belongs to, and since
356 * this is only a read and not a write, and since it is still in the same page,
357 * it should not matter and this makes the code much simpler.
358 */
359static inline void ntfs_fault_in_pages_readable(const char __user *uaddr,
360 int bytes)
361{
362 const char __user *end;
363 volatile char c;
364
365 /* Set @end to the first byte outside the last page we care about. */
366 end = (const char __user*)PAGE_ALIGN((ptrdiff_t __user)uaddr + bytes);
367
368 while (!__get_user(c, uaddr) && (uaddr += PAGE_SIZE, uaddr < end))
369 ;
370}
371
372/**
373 * ntfs_fault_in_pages_readable_iovec -
374 *
375 * Same as ntfs_fault_in_pages_readable() but operates on an array of iovecs.
376 */
377static inline void ntfs_fault_in_pages_readable_iovec(const struct iovec *iov,
378 size_t iov_ofs, int bytes)
379{
380 do {
381 const char __user *buf;
382 unsigned len;
383
384 buf = iov->iov_base + iov_ofs;
385 len = iov->iov_len - iov_ofs;
386 if (len > bytes)
387 len = bytes;
388 ntfs_fault_in_pages_readable(buf, len);
389 bytes -= len;
390 iov++;
391 iov_ofs = 0;
392 } while (bytes);
393}
394
395/**
396 * __ntfs_grab_cache_pages - obtain a number of locked pages
397 * @mapping: address space mapping from which to obtain page cache pages
398 * @index: starting index in @mapping at which to begin obtaining pages
399 * @nr_pages: number of page cache pages to obtain
400 * @pages: array of pages in which to return the obtained page cache pages
401 * @cached_page: allocated but as yet unused page
402 * @lru_pvec: lru-buffering pagevec of caller
403 *
404 * Obtain @nr_pages locked page cache pages from the mapping @maping and
405 * starting at index @index.
406 *
407 * If a page is newly created, increment its refcount and add it to the
408 * caller's lru-buffering pagevec @lru_pvec.
409 *
410 * This is the same as mm/filemap.c::__grab_cache_page(), except that @nr_pages
411 * are obtained at once instead of just one page and that 0 is returned on
412 * success and -errno on error.
413 *
414 * Note, the page locks are obtained in ascending page index order.
415 */
416static inline int __ntfs_grab_cache_pages(struct address_space *mapping,
417 pgoff_t index, const unsigned nr_pages, struct page **pages,
418 struct page **cached_page, struct pagevec *lru_pvec)
419{
420 int err, nr;
421
422 BUG_ON(!nr_pages);
423 err = nr = 0;
424 do {
425 pages[nr] = find_lock_page(mapping, index);
426 if (!pages[nr]) {
427 if (!*cached_page) {
428 *cached_page = page_cache_alloc(mapping);
429 if (unlikely(!*cached_page)) {
430 err = -ENOMEM;
431 goto err_out;
432 }
433 }
434 err = add_to_page_cache(*cached_page, mapping, index,
435 GFP_KERNEL);
436 if (unlikely(err)) {
437 if (err == -EEXIST)
438 continue;
439 goto err_out;
440 }
441 pages[nr] = *cached_page;
442 page_cache_get(*cached_page);
443 if (unlikely(!pagevec_add(lru_pvec, *cached_page)))
444 __pagevec_lru_add(lru_pvec);
445 *cached_page = NULL;
446 }
447 index++;
448 nr++;
449 } while (nr < nr_pages);
450out:
451 return err;
452err_out:
453 while (nr > 0) {
454 unlock_page(pages[--nr]);
455 page_cache_release(pages[nr]);
456 }
457 goto out;
458}
459
460static inline int ntfs_submit_bh_for_read(struct buffer_head *bh)
461{
462 lock_buffer(bh);
463 get_bh(bh);
464 bh->b_end_io = end_buffer_read_sync;
465 return submit_bh(READ, bh);
466}
467
468/**
469 * ntfs_prepare_pages_for_non_resident_write - prepare pages for receiving data
470 * @pages: array of destination pages
471 * @nr_pages: number of pages in @pages
472 * @pos: byte position in file at which the write begins
473 * @bytes: number of bytes to be written
474 *
475 * This is called for non-resident attributes from ntfs_file_buffered_write()
476 * with i_sem held on the inode (@pages[0]->mapping->host). There are
477 * @nr_pages pages in @pages which are locked but not kmap()ped. The source
478 * data has not yet been copied into the @pages.
479 *
480 * Need to fill any holes with actual clusters, allocate buffers if necessary,
481 * ensure all the buffers are mapped, and bring uptodate any buffers that are
482 * only partially being written to.
483 *
484 * If @nr_pages is greater than one, we are guaranteed that the cluster size is
485 * greater than PAGE_CACHE_SIZE, that all pages in @pages are entirely inside
486 * the same cluster and that they are the entirety of that cluster, and that
487 * the cluster is sparse, i.e. we need to allocate a cluster to fill the hole.
488 *
489 * i_size is not to be modified yet.
490 *
491 * Return 0 on success or -errno on error.
492 */
493static int ntfs_prepare_pages_for_non_resident_write(struct page **pages,
494 unsigned nr_pages, s64 pos, size_t bytes)
495{
496 VCN vcn, highest_vcn = 0, cpos, cend, bh_cpos, bh_cend;
497 LCN lcn;
498 s64 bh_pos, vcn_len, end, initialized_size;
499 sector_t lcn_block;
500 struct page *page;
501 struct inode *vi;
502 ntfs_inode *ni, *base_ni = NULL;
503 ntfs_volume *vol;
504 runlist_element *rl, *rl2;
505 struct buffer_head *bh, *head, *wait[2], **wait_bh = wait;
506 ntfs_attr_search_ctx *ctx = NULL;
507 MFT_RECORD *m = NULL;
508 ATTR_RECORD *a = NULL;
509 unsigned long flags;
510 u32 attr_rec_len = 0;
511 unsigned blocksize, u;
512 int err, mp_size;
513 BOOL rl_write_locked, was_hole, is_retry;
514 unsigned char blocksize_bits;
515 struct {
516 u8 runlist_merged:1;
517 u8 mft_attr_mapped:1;
518 u8 mp_rebuilt:1;
519 u8 attr_switched:1;
520 } status = { 0, 0, 0, 0 };
521
522 BUG_ON(!nr_pages);
523 BUG_ON(!pages);
524 BUG_ON(!*pages);
525 vi = pages[0]->mapping->host;
526 ni = NTFS_I(vi);
527 vol = ni->vol;
528 ntfs_debug("Entering for inode 0x%lx, attribute type 0x%x, start page "
Anton Altaparmakovd04bd1f2005-10-24 08:41:24 +0100529 "index 0x%lx, nr_pages 0x%x, pos 0x%llx, bytes 0x%zx.",
Anton Altaparmakov98b27032005-10-11 15:40:40 +0100530 vi->i_ino, ni->type, pages[0]->index, nr_pages,
531 (long long)pos, bytes);
532 blocksize_bits = vi->i_blkbits;
533 blocksize = 1 << blocksize_bits;
534 u = 0;
535 do {
536 struct page *page = pages[u];
537 /*
538 * create_empty_buffers() will create uptodate/dirty buffers if
539 * the page is uptodate/dirty.
540 */
541 if (!page_has_buffers(page)) {
542 create_empty_buffers(page, blocksize, 0);
543 if (unlikely(!page_has_buffers(page)))
544 return -ENOMEM;
545 }
546 } while (++u < nr_pages);
547 rl_write_locked = FALSE;
548 rl = NULL;
549 err = 0;
550 vcn = lcn = -1;
551 vcn_len = 0;
552 lcn_block = -1;
553 was_hole = FALSE;
554 cpos = pos >> vol->cluster_size_bits;
555 end = pos + bytes;
556 cend = (end + vol->cluster_size - 1) >> vol->cluster_size_bits;
557 /*
558 * Loop over each page and for each page over each buffer. Use goto to
559 * reduce indentation.
560 */
561 u = 0;
562do_next_page:
563 page = pages[u];
564 bh_pos = (s64)page->index << PAGE_CACHE_SHIFT;
565 bh = head = page_buffers(page);
566 do {
567 VCN cdelta;
568 s64 bh_end;
569 unsigned bh_cofs;
570
571 /* Clear buffer_new on all buffers to reinitialise state. */
572 if (buffer_new(bh))
573 clear_buffer_new(bh);
574 bh_end = bh_pos + blocksize;
575 bh_cpos = bh_pos >> vol->cluster_size_bits;
576 bh_cofs = bh_pos & vol->cluster_size_mask;
577 if (buffer_mapped(bh)) {
578 /*
579 * The buffer is already mapped. If it is uptodate,
580 * ignore it.
581 */
582 if (buffer_uptodate(bh))
583 continue;
584 /*
585 * The buffer is not uptodate. If the page is uptodate
586 * set the buffer uptodate and otherwise ignore it.
587 */
588 if (PageUptodate(page)) {
589 set_buffer_uptodate(bh);
590 continue;
591 }
592 /*
593 * Neither the page nor the buffer are uptodate. If
594 * the buffer is only partially being written to, we
595 * need to read it in before the write, i.e. now.
596 */
597 if ((bh_pos < pos && bh_end > pos) ||
598 (bh_pos < end && bh_end > end)) {
599 /*
600 * If the buffer is fully or partially within
601 * the initialized size, do an actual read.
602 * Otherwise, simply zero the buffer.
603 */
604 read_lock_irqsave(&ni->size_lock, flags);
605 initialized_size = ni->initialized_size;
606 read_unlock_irqrestore(&ni->size_lock, flags);
607 if (bh_pos < initialized_size) {
608 ntfs_submit_bh_for_read(bh);
609 *wait_bh++ = bh;
610 } else {
611 u8 *kaddr = kmap_atomic(page, KM_USER0);
612 memset(kaddr + bh_offset(bh), 0,
613 blocksize);
614 kunmap_atomic(kaddr, KM_USER0);
615 flush_dcache_page(page);
616 set_buffer_uptodate(bh);
617 }
618 }
619 continue;
620 }
621 /* Unmapped buffer. Need to map it. */
622 bh->b_bdev = vol->sb->s_bdev;
623 /*
624 * If the current buffer is in the same clusters as the map
625 * cache, there is no need to check the runlist again. The
626 * map cache is made up of @vcn, which is the first cached file
627 * cluster, @vcn_len which is the number of cached file
628 * clusters, @lcn is the device cluster corresponding to @vcn,
629 * and @lcn_block is the block number corresponding to @lcn.
630 */
631 cdelta = bh_cpos - vcn;
632 if (likely(!cdelta || (cdelta > 0 && cdelta < vcn_len))) {
633map_buffer_cached:
634 BUG_ON(lcn < 0);
635 bh->b_blocknr = lcn_block +
636 (cdelta << (vol->cluster_size_bits -
637 blocksize_bits)) +
638 (bh_cofs >> blocksize_bits);
639 set_buffer_mapped(bh);
640 /*
641 * If the page is uptodate so is the buffer. If the
642 * buffer is fully outside the write, we ignore it if
643 * it was already allocated and we mark it dirty so it
644 * gets written out if we allocated it. On the other
645 * hand, if we allocated the buffer but we are not
646 * marking it dirty we set buffer_new so we can do
647 * error recovery.
648 */
649 if (PageUptodate(page)) {
650 if (!buffer_uptodate(bh))
651 set_buffer_uptodate(bh);
652 if (unlikely(was_hole)) {
653 /* We allocated the buffer. */
654 unmap_underlying_metadata(bh->b_bdev,
655 bh->b_blocknr);
656 if (bh_end <= pos || bh_pos >= end)
657 mark_buffer_dirty(bh);
658 else
659 set_buffer_new(bh);
660 }
661 continue;
662 }
663 /* Page is _not_ uptodate. */
664 if (likely(!was_hole)) {
665 /*
666 * Buffer was already allocated. If it is not
667 * uptodate and is only partially being written
668 * to, we need to read it in before the write,
669 * i.e. now.
670 */
Anton Altaparmakov3aebf252005-11-01 15:49:31 +0000671 if (!buffer_uptodate(bh) && bh_pos < end &&
672 bh_end > pos &&
673 (bh_pos < pos ||
674 bh_end > end)) {
Anton Altaparmakov98b27032005-10-11 15:40:40 +0100675 /*
676 * If the buffer is fully or partially
677 * within the initialized size, do an
678 * actual read. Otherwise, simply zero
679 * the buffer.
680 */
681 read_lock_irqsave(&ni->size_lock,
682 flags);
683 initialized_size = ni->initialized_size;
684 read_unlock_irqrestore(&ni->size_lock,
685 flags);
686 if (bh_pos < initialized_size) {
687 ntfs_submit_bh_for_read(bh);
688 *wait_bh++ = bh;
689 } else {
690 u8 *kaddr = kmap_atomic(page,
691 KM_USER0);
692 memset(kaddr + bh_offset(bh),
693 0, blocksize);
694 kunmap_atomic(kaddr, KM_USER0);
695 flush_dcache_page(page);
696 set_buffer_uptodate(bh);
697 }
698 }
699 continue;
700 }
701 /* We allocated the buffer. */
702 unmap_underlying_metadata(bh->b_bdev, bh->b_blocknr);
703 /*
704 * If the buffer is fully outside the write, zero it,
705 * set it uptodate, and mark it dirty so it gets
706 * written out. If it is partially being written to,
707 * zero region surrounding the write but leave it to
708 * commit write to do anything else. Finally, if the
709 * buffer is fully being overwritten, do nothing.
710 */
711 if (bh_end <= pos || bh_pos >= end) {
712 if (!buffer_uptodate(bh)) {
713 u8 *kaddr = kmap_atomic(page, KM_USER0);
714 memset(kaddr + bh_offset(bh), 0,
715 blocksize);
716 kunmap_atomic(kaddr, KM_USER0);
717 flush_dcache_page(page);
718 set_buffer_uptodate(bh);
719 }
720 mark_buffer_dirty(bh);
721 continue;
722 }
723 set_buffer_new(bh);
724 if (!buffer_uptodate(bh) &&
725 (bh_pos < pos || bh_end > end)) {
726 u8 *kaddr;
727 unsigned pofs;
728
729 kaddr = kmap_atomic(page, KM_USER0);
730 if (bh_pos < pos) {
731 pofs = bh_pos & ~PAGE_CACHE_MASK;
732 memset(kaddr + pofs, 0, pos - bh_pos);
733 }
734 if (bh_end > end) {
735 pofs = end & ~PAGE_CACHE_MASK;
736 memset(kaddr + pofs, 0, bh_end - end);
737 }
738 kunmap_atomic(kaddr, KM_USER0);
739 flush_dcache_page(page);
740 }
741 continue;
742 }
743 /*
744 * Slow path: this is the first buffer in the cluster. If it
745 * is outside allocated size and is not uptodate, zero it and
746 * set it uptodate.
747 */
748 read_lock_irqsave(&ni->size_lock, flags);
749 initialized_size = ni->allocated_size;
750 read_unlock_irqrestore(&ni->size_lock, flags);
751 if (bh_pos > initialized_size) {
752 if (PageUptodate(page)) {
753 if (!buffer_uptodate(bh))
754 set_buffer_uptodate(bh);
755 } else if (!buffer_uptodate(bh)) {
756 u8 *kaddr = kmap_atomic(page, KM_USER0);
757 memset(kaddr + bh_offset(bh), 0, blocksize);
758 kunmap_atomic(kaddr, KM_USER0);
759 flush_dcache_page(page);
760 set_buffer_uptodate(bh);
761 }
762 continue;
763 }
764 is_retry = FALSE;
765 if (!rl) {
766 down_read(&ni->runlist.lock);
767retry_remap:
768 rl = ni->runlist.rl;
769 }
770 if (likely(rl != NULL)) {
771 /* Seek to element containing target cluster. */
772 while (rl->length && rl[1].vcn <= bh_cpos)
773 rl++;
774 lcn = ntfs_rl_vcn_to_lcn(rl, bh_cpos);
775 if (likely(lcn >= 0)) {
776 /*
777 * Successful remap, setup the map cache and
778 * use that to deal with the buffer.
779 */
780 was_hole = FALSE;
781 vcn = bh_cpos;
782 vcn_len = rl[1].vcn - vcn;
783 lcn_block = lcn << (vol->cluster_size_bits -
784 blocksize_bits);
Anton Altaparmakovd5aeaef2005-10-19 12:23:10 +0100785 cdelta = 0;
Anton Altaparmakov98b27032005-10-11 15:40:40 +0100786 /*
Anton Altaparmakov3aebf252005-11-01 15:49:31 +0000787 * If the number of remaining clusters touched
788 * by the write is smaller or equal to the
789 * number of cached clusters, unlock the
790 * runlist as the map cache will be used from
791 * now on.
Anton Altaparmakov98b27032005-10-11 15:40:40 +0100792 */
793 if (likely(vcn + vcn_len >= cend)) {
794 if (rl_write_locked) {
795 up_write(&ni->runlist.lock);
796 rl_write_locked = FALSE;
797 } else
798 up_read(&ni->runlist.lock);
799 rl = NULL;
800 }
801 goto map_buffer_cached;
802 }
803 } else
804 lcn = LCN_RL_NOT_MAPPED;
805 /*
806 * If it is not a hole and not out of bounds, the runlist is
807 * probably unmapped so try to map it now.
808 */
809 if (unlikely(lcn != LCN_HOLE && lcn != LCN_ENOENT)) {
810 if (likely(!is_retry && lcn == LCN_RL_NOT_MAPPED)) {
811 /* Attempt to map runlist. */
812 if (!rl_write_locked) {
813 /*
814 * We need the runlist locked for
815 * writing, so if it is locked for
816 * reading relock it now and retry in
817 * case it changed whilst we dropped
818 * the lock.
819 */
820 up_read(&ni->runlist.lock);
821 down_write(&ni->runlist.lock);
822 rl_write_locked = TRUE;
823 goto retry_remap;
824 }
825 err = ntfs_map_runlist_nolock(ni, bh_cpos,
826 NULL);
827 if (likely(!err)) {
828 is_retry = TRUE;
829 goto retry_remap;
830 }
831 /*
832 * If @vcn is out of bounds, pretend @lcn is
833 * LCN_ENOENT. As long as the buffer is out
834 * of bounds this will work fine.
835 */
836 if (err == -ENOENT) {
837 lcn = LCN_ENOENT;
838 err = 0;
839 goto rl_not_mapped_enoent;
840 }
841 } else
842 err = -EIO;
843 /* Failed to map the buffer, even after retrying. */
844 bh->b_blocknr = -1;
845 ntfs_error(vol->sb, "Failed to write to inode 0x%lx, "
846 "attribute type 0x%x, vcn 0x%llx, "
847 "vcn offset 0x%x, because its "
848 "location on disk could not be "
849 "determined%s (error code %i).",
850 ni->mft_no, ni->type,
851 (unsigned long long)bh_cpos,
852 (unsigned)bh_pos &
853 vol->cluster_size_mask,
854 is_retry ? " even after retrying" : "",
855 err);
856 break;
857 }
858rl_not_mapped_enoent:
859 /*
860 * The buffer is in a hole or out of bounds. We need to fill
861 * the hole, unless the buffer is in a cluster which is not
862 * touched by the write, in which case we just leave the buffer
863 * unmapped. This can only happen when the cluster size is
864 * less than the page cache size.
865 */
866 if (unlikely(vol->cluster_size < PAGE_CACHE_SIZE)) {
867 bh_cend = (bh_end + vol->cluster_size - 1) >>
868 vol->cluster_size_bits;
869 if ((bh_cend <= cpos || bh_cpos >= cend)) {
870 bh->b_blocknr = -1;
871 /*
872 * If the buffer is uptodate we skip it. If it
873 * is not but the page is uptodate, we can set
874 * the buffer uptodate. If the page is not
875 * uptodate, we can clear the buffer and set it
876 * uptodate. Whether this is worthwhile is
877 * debatable and this could be removed.
878 */
879 if (PageUptodate(page)) {
880 if (!buffer_uptodate(bh))
881 set_buffer_uptodate(bh);
882 } else if (!buffer_uptodate(bh)) {
883 u8 *kaddr = kmap_atomic(page, KM_USER0);
884 memset(kaddr + bh_offset(bh), 0,
885 blocksize);
886 kunmap_atomic(kaddr, KM_USER0);
887 flush_dcache_page(page);
888 set_buffer_uptodate(bh);
889 }
890 continue;
891 }
892 }
893 /*
894 * Out of bounds buffer is invalid if it was not really out of
895 * bounds.
896 */
897 BUG_ON(lcn != LCN_HOLE);
898 /*
899 * We need the runlist locked for writing, so if it is locked
900 * for reading relock it now and retry in case it changed
901 * whilst we dropped the lock.
902 */
903 BUG_ON(!rl);
904 if (!rl_write_locked) {
905 up_read(&ni->runlist.lock);
906 down_write(&ni->runlist.lock);
907 rl_write_locked = TRUE;
908 goto retry_remap;
909 }
910 /* Find the previous last allocated cluster. */
911 BUG_ON(rl->lcn != LCN_HOLE);
912 lcn = -1;
913 rl2 = rl;
914 while (--rl2 >= ni->runlist.rl) {
915 if (rl2->lcn >= 0) {
916 lcn = rl2->lcn + rl2->length;
917 break;
918 }
919 }
920 rl2 = ntfs_cluster_alloc(vol, bh_cpos, 1, lcn, DATA_ZONE,
921 FALSE);
922 if (IS_ERR(rl2)) {
923 err = PTR_ERR(rl2);
924 ntfs_debug("Failed to allocate cluster, error code %i.",
925 err);
926 break;
927 }
928 lcn = rl2->lcn;
929 rl = ntfs_runlists_merge(ni->runlist.rl, rl2);
930 if (IS_ERR(rl)) {
931 err = PTR_ERR(rl);
932 if (err != -ENOMEM)
933 err = -EIO;
934 if (ntfs_cluster_free_from_rl(vol, rl2)) {
935 ntfs_error(vol->sb, "Failed to release "
936 "allocated cluster in error "
937 "code path. Run chkdsk to "
938 "recover the lost cluster.");
939 NVolSetErrors(vol);
940 }
941 ntfs_free(rl2);
942 break;
943 }
944 ni->runlist.rl = rl;
945 status.runlist_merged = 1;
946 ntfs_debug("Allocated cluster, lcn 0x%llx.", lcn);
947 /* Map and lock the mft record and get the attribute record. */
948 if (!NInoAttr(ni))
949 base_ni = ni;
950 else
951 base_ni = ni->ext.base_ntfs_ino;
952 m = map_mft_record(base_ni);
953 if (IS_ERR(m)) {
954 err = PTR_ERR(m);
955 break;
956 }
957 ctx = ntfs_attr_get_search_ctx(base_ni, m);
958 if (unlikely(!ctx)) {
959 err = -ENOMEM;
960 unmap_mft_record(base_ni);
961 break;
962 }
963 status.mft_attr_mapped = 1;
964 err = ntfs_attr_lookup(ni->type, ni->name, ni->name_len,
965 CASE_SENSITIVE, bh_cpos, NULL, 0, ctx);
966 if (unlikely(err)) {
967 if (err == -ENOENT)
968 err = -EIO;
969 break;
970 }
971 m = ctx->mrec;
972 a = ctx->attr;
973 /*
974 * Find the runlist element with which the attribute extent
975 * starts. Note, we cannot use the _attr_ version because we
976 * have mapped the mft record. That is ok because we know the
977 * runlist fragment must be mapped already to have ever gotten
978 * here, so we can just use the _rl_ version.
979 */
980 vcn = sle64_to_cpu(a->data.non_resident.lowest_vcn);
981 rl2 = ntfs_rl_find_vcn_nolock(rl, vcn);
982 BUG_ON(!rl2);
983 BUG_ON(!rl2->length);
984 BUG_ON(rl2->lcn < LCN_HOLE);
985 highest_vcn = sle64_to_cpu(a->data.non_resident.highest_vcn);
986 /*
987 * If @highest_vcn is zero, calculate the real highest_vcn
988 * (which can really be zero).
989 */
990 if (!highest_vcn)
991 highest_vcn = (sle64_to_cpu(
992 a->data.non_resident.allocated_size) >>
993 vol->cluster_size_bits) - 1;
994 /*
995 * Determine the size of the mapping pairs array for the new
996 * extent, i.e. the old extent with the hole filled.
997 */
998 mp_size = ntfs_get_size_for_mapping_pairs(vol, rl2, vcn,
999 highest_vcn);
1000 if (unlikely(mp_size <= 0)) {
1001 if (!(err = mp_size))
1002 err = -EIO;
1003 ntfs_debug("Failed to get size for mapping pairs "
1004 "array, error code %i.", err);
1005 break;
1006 }
1007 /*
1008 * Resize the attribute record to fit the new mapping pairs
1009 * array.
1010 */
1011 attr_rec_len = le32_to_cpu(a->length);
1012 err = ntfs_attr_record_resize(m, a, mp_size + le16_to_cpu(
1013 a->data.non_resident.mapping_pairs_offset));
1014 if (unlikely(err)) {
1015 BUG_ON(err != -ENOSPC);
1016 // TODO: Deal with this by using the current attribute
1017 // and fill it with as much of the mapping pairs
1018 // array as possible. Then loop over each attribute
1019 // extent rewriting the mapping pairs arrays as we go
1020 // along and if when we reach the end we have not
1021 // enough space, try to resize the last attribute
1022 // extent and if even that fails, add a new attribute
1023 // extent.
1024 // We could also try to resize at each step in the hope
1025 // that we will not need to rewrite every single extent.
1026 // Note, we may need to decompress some extents to fill
1027 // the runlist as we are walking the extents...
1028 ntfs_error(vol->sb, "Not enough space in the mft "
1029 "record for the extended attribute "
1030 "record. This case is not "
1031 "implemented yet.");
1032 err = -EOPNOTSUPP;
1033 break ;
1034 }
1035 status.mp_rebuilt = 1;
1036 /*
1037 * Generate the mapping pairs array directly into the attribute
1038 * record.
1039 */
1040 err = ntfs_mapping_pairs_build(vol, (u8*)a + le16_to_cpu(
1041 a->data.non_resident.mapping_pairs_offset),
1042 mp_size, rl2, vcn, highest_vcn, NULL);
1043 if (unlikely(err)) {
1044 ntfs_error(vol->sb, "Cannot fill hole in inode 0x%lx, "
1045 "attribute type 0x%x, because building "
1046 "the mapping pairs failed with error "
1047 "code %i.", vi->i_ino,
1048 (unsigned)le32_to_cpu(ni->type), err);
1049 err = -EIO;
1050 break;
1051 }
1052 /* Update the highest_vcn but only if it was not set. */
1053 if (unlikely(!a->data.non_resident.highest_vcn))
1054 a->data.non_resident.highest_vcn =
1055 cpu_to_sle64(highest_vcn);
1056 /*
1057 * If the attribute is sparse/compressed, update the compressed
1058 * size in the ntfs_inode structure and the attribute record.
1059 */
1060 if (likely(NInoSparse(ni) || NInoCompressed(ni))) {
1061 /*
1062 * If we are not in the first attribute extent, switch
1063 * to it, but first ensure the changes will make it to
1064 * disk later.
1065 */
1066 if (a->data.non_resident.lowest_vcn) {
1067 flush_dcache_mft_record_page(ctx->ntfs_ino);
1068 mark_mft_record_dirty(ctx->ntfs_ino);
1069 ntfs_attr_reinit_search_ctx(ctx);
1070 err = ntfs_attr_lookup(ni->type, ni->name,
1071 ni->name_len, CASE_SENSITIVE,
1072 0, NULL, 0, ctx);
1073 if (unlikely(err)) {
1074 status.attr_switched = 1;
1075 break;
1076 }
1077 /* @m is not used any more so do not set it. */
1078 a = ctx->attr;
1079 }
1080 write_lock_irqsave(&ni->size_lock, flags);
1081 ni->itype.compressed.size += vol->cluster_size;
1082 a->data.non_resident.compressed_size =
1083 cpu_to_sle64(ni->itype.compressed.size);
1084 write_unlock_irqrestore(&ni->size_lock, flags);
1085 }
1086 /* Ensure the changes make it to disk. */
1087 flush_dcache_mft_record_page(ctx->ntfs_ino);
1088 mark_mft_record_dirty(ctx->ntfs_ino);
1089 ntfs_attr_put_search_ctx(ctx);
1090 unmap_mft_record(base_ni);
1091 /* Successfully filled the hole. */
1092 status.runlist_merged = 0;
1093 status.mft_attr_mapped = 0;
1094 status.mp_rebuilt = 0;
1095 /* Setup the map cache and use that to deal with the buffer. */
1096 was_hole = TRUE;
1097 vcn = bh_cpos;
1098 vcn_len = 1;
1099 lcn_block = lcn << (vol->cluster_size_bits - blocksize_bits);
1100 cdelta = 0;
1101 /*
1102 * If the number of remaining clusters in the @pages is smaller
1103 * or equal to the number of cached clusters, unlock the
1104 * runlist as the map cache will be used from now on.
1105 */
1106 if (likely(vcn + vcn_len >= cend)) {
1107 up_write(&ni->runlist.lock);
1108 rl_write_locked = FALSE;
1109 rl = NULL;
1110 }
1111 goto map_buffer_cached;
1112 } while (bh_pos += blocksize, (bh = bh->b_this_page) != head);
1113 /* If there are no errors, do the next page. */
1114 if (likely(!err && ++u < nr_pages))
1115 goto do_next_page;
1116 /* If there are no errors, release the runlist lock if we took it. */
1117 if (likely(!err)) {
1118 if (unlikely(rl_write_locked)) {
1119 up_write(&ni->runlist.lock);
1120 rl_write_locked = FALSE;
1121 } else if (unlikely(rl))
1122 up_read(&ni->runlist.lock);
1123 rl = NULL;
1124 }
1125 /* If we issued read requests, let them complete. */
1126 read_lock_irqsave(&ni->size_lock, flags);
1127 initialized_size = ni->initialized_size;
1128 read_unlock_irqrestore(&ni->size_lock, flags);
1129 while (wait_bh > wait) {
1130 bh = *--wait_bh;
1131 wait_on_buffer(bh);
1132 if (likely(buffer_uptodate(bh))) {
1133 page = bh->b_page;
1134 bh_pos = ((s64)page->index << PAGE_CACHE_SHIFT) +
1135 bh_offset(bh);
1136 /*
1137 * If the buffer overflows the initialized size, need
1138 * to zero the overflowing region.
1139 */
1140 if (unlikely(bh_pos + blocksize > initialized_size)) {
1141 u8 *kaddr;
1142 int ofs = 0;
1143
1144 if (likely(bh_pos < initialized_size))
1145 ofs = initialized_size - bh_pos;
1146 kaddr = kmap_atomic(page, KM_USER0);
1147 memset(kaddr + bh_offset(bh) + ofs, 0,
1148 blocksize - ofs);
1149 kunmap_atomic(kaddr, KM_USER0);
1150 flush_dcache_page(page);
1151 }
1152 } else /* if (unlikely(!buffer_uptodate(bh))) */
1153 err = -EIO;
1154 }
1155 if (likely(!err)) {
1156 /* Clear buffer_new on all buffers. */
1157 u = 0;
1158 do {
1159 bh = head = page_buffers(pages[u]);
1160 do {
1161 if (buffer_new(bh))
1162 clear_buffer_new(bh);
1163 } while ((bh = bh->b_this_page) != head);
1164 } while (++u < nr_pages);
1165 ntfs_debug("Done.");
1166 return err;
1167 }
1168 if (status.attr_switched) {
1169 /* Get back to the attribute extent we modified. */
1170 ntfs_attr_reinit_search_ctx(ctx);
1171 if (ntfs_attr_lookup(ni->type, ni->name, ni->name_len,
1172 CASE_SENSITIVE, bh_cpos, NULL, 0, ctx)) {
1173 ntfs_error(vol->sb, "Failed to find required "
1174 "attribute extent of attribute in "
1175 "error code path. Run chkdsk to "
1176 "recover.");
1177 write_lock_irqsave(&ni->size_lock, flags);
1178 ni->itype.compressed.size += vol->cluster_size;
1179 write_unlock_irqrestore(&ni->size_lock, flags);
1180 flush_dcache_mft_record_page(ctx->ntfs_ino);
1181 mark_mft_record_dirty(ctx->ntfs_ino);
1182 /*
1183 * The only thing that is now wrong is the compressed
1184 * size of the base attribute extent which chkdsk
1185 * should be able to fix.
1186 */
1187 NVolSetErrors(vol);
1188 } else {
1189 m = ctx->mrec;
1190 a = ctx->attr;
1191 status.attr_switched = 0;
1192 }
1193 }
1194 /*
1195 * If the runlist has been modified, need to restore it by punching a
1196 * hole into it and we then need to deallocate the on-disk cluster as
1197 * well. Note, we only modify the runlist if we are able to generate a
1198 * new mapping pairs array, i.e. only when the mapped attribute extent
1199 * is not switched.
1200 */
1201 if (status.runlist_merged && !status.attr_switched) {
1202 BUG_ON(!rl_write_locked);
1203 /* Make the file cluster we allocated sparse in the runlist. */
1204 if (ntfs_rl_punch_nolock(vol, &ni->runlist, bh_cpos, 1)) {
1205 ntfs_error(vol->sb, "Failed to punch hole into "
1206 "attribute runlist in error code "
1207 "path. Run chkdsk to recover the "
1208 "lost cluster.");
1209 make_bad_inode(vi);
1210 make_bad_inode(VFS_I(base_ni));
1211 NVolSetErrors(vol);
1212 } else /* if (success) */ {
1213 status.runlist_merged = 0;
1214 /*
1215 * Deallocate the on-disk cluster we allocated but only
1216 * if we succeeded in punching its vcn out of the
1217 * runlist.
1218 */
1219 down_write(&vol->lcnbmp_lock);
1220 if (ntfs_bitmap_clear_bit(vol->lcnbmp_ino, lcn)) {
1221 ntfs_error(vol->sb, "Failed to release "
1222 "allocated cluster in error "
1223 "code path. Run chkdsk to "
1224 "recover the lost cluster.");
1225 NVolSetErrors(vol);
1226 }
1227 up_write(&vol->lcnbmp_lock);
1228 }
1229 }
1230 /*
1231 * Resize the attribute record to its old size and rebuild the mapping
1232 * pairs array. Note, we only can do this if the runlist has been
1233 * restored to its old state which also implies that the mapped
1234 * attribute extent is not switched.
1235 */
1236 if (status.mp_rebuilt && !status.runlist_merged) {
1237 if (ntfs_attr_record_resize(m, a, attr_rec_len)) {
1238 ntfs_error(vol->sb, "Failed to restore attribute "
1239 "record in error code path. Run "
1240 "chkdsk to recover.");
1241 make_bad_inode(vi);
1242 make_bad_inode(VFS_I(base_ni));
1243 NVolSetErrors(vol);
1244 } else /* if (success) */ {
1245 if (ntfs_mapping_pairs_build(vol, (u8*)a +
1246 le16_to_cpu(a->data.non_resident.
1247 mapping_pairs_offset), attr_rec_len -
1248 le16_to_cpu(a->data.non_resident.
1249 mapping_pairs_offset), ni->runlist.rl,
1250 vcn, highest_vcn, NULL)) {
1251 ntfs_error(vol->sb, "Failed to restore "
1252 "mapping pairs array in error "
1253 "code path. Run chkdsk to "
1254 "recover.");
1255 make_bad_inode(vi);
1256 make_bad_inode(VFS_I(base_ni));
1257 NVolSetErrors(vol);
1258 }
1259 flush_dcache_mft_record_page(ctx->ntfs_ino);
1260 mark_mft_record_dirty(ctx->ntfs_ino);
1261 }
1262 }
1263 /* Release the mft record and the attribute. */
1264 if (status.mft_attr_mapped) {
1265 ntfs_attr_put_search_ctx(ctx);
1266 unmap_mft_record(base_ni);
1267 }
1268 /* Release the runlist lock. */
1269 if (rl_write_locked)
1270 up_write(&ni->runlist.lock);
1271 else if (rl)
1272 up_read(&ni->runlist.lock);
1273 /*
1274 * Zero out any newly allocated blocks to avoid exposing stale data.
1275 * If BH_New is set, we know that the block was newly allocated above
1276 * and that it has not been fully zeroed and marked dirty yet.
1277 */
1278 nr_pages = u;
1279 u = 0;
1280 end = bh_cpos << vol->cluster_size_bits;
1281 do {
1282 page = pages[u];
1283 bh = head = page_buffers(page);
1284 do {
1285 if (u == nr_pages &&
1286 ((s64)page->index << PAGE_CACHE_SHIFT) +
1287 bh_offset(bh) >= end)
1288 break;
1289 if (!buffer_new(bh))
1290 continue;
1291 clear_buffer_new(bh);
1292 if (!buffer_uptodate(bh)) {
1293 if (PageUptodate(page))
1294 set_buffer_uptodate(bh);
1295 else {
1296 u8 *kaddr = kmap_atomic(page, KM_USER0);
1297 memset(kaddr + bh_offset(bh), 0,
1298 blocksize);
1299 kunmap_atomic(kaddr, KM_USER0);
1300 flush_dcache_page(page);
1301 set_buffer_uptodate(bh);
1302 }
1303 }
1304 mark_buffer_dirty(bh);
1305 } while ((bh = bh->b_this_page) != head);
1306 } while (++u <= nr_pages);
1307 ntfs_error(vol->sb, "Failed. Returning error code %i.", err);
1308 return err;
1309}
1310
1311/*
1312 * Copy as much as we can into the pages and return the number of bytes which
1313 * were sucessfully copied. If a fault is encountered then clear the pages
1314 * out to (ofs + bytes) and return the number of bytes which were copied.
1315 */
1316static inline size_t ntfs_copy_from_user(struct page **pages,
1317 unsigned nr_pages, unsigned ofs, const char __user *buf,
1318 size_t bytes)
1319{
1320 struct page **last_page = pages + nr_pages;
1321 char *kaddr;
1322 size_t total = 0;
1323 unsigned len;
1324 int left;
1325
1326 do {
1327 len = PAGE_CACHE_SIZE - ofs;
1328 if (len > bytes)
1329 len = bytes;
1330 kaddr = kmap_atomic(*pages, KM_USER0);
1331 left = __copy_from_user_inatomic(kaddr + ofs, buf, len);
1332 kunmap_atomic(kaddr, KM_USER0);
1333 if (unlikely(left)) {
1334 /* Do it the slow way. */
1335 kaddr = kmap(*pages);
1336 left = __copy_from_user(kaddr + ofs, buf, len);
1337 kunmap(*pages);
1338 if (unlikely(left))
1339 goto err_out;
1340 }
1341 total += len;
1342 bytes -= len;
1343 if (!bytes)
1344 break;
1345 buf += len;
1346 ofs = 0;
1347 } while (++pages < last_page);
1348out:
1349 return total;
1350err_out:
1351 total += len - left;
1352 /* Zero the rest of the target like __copy_from_user(). */
1353 while (++pages < last_page) {
1354 bytes -= len;
1355 if (!bytes)
1356 break;
1357 len = PAGE_CACHE_SIZE;
1358 if (len > bytes)
1359 len = bytes;
1360 kaddr = kmap_atomic(*pages, KM_USER0);
1361 memset(kaddr, 0, len);
1362 kunmap_atomic(kaddr, KM_USER0);
1363 }
1364 goto out;
1365}
1366
1367static size_t __ntfs_copy_from_user_iovec(char *vaddr,
1368 const struct iovec *iov, size_t iov_ofs, size_t bytes)
1369{
1370 size_t total = 0;
1371
1372 while (1) {
1373 const char __user *buf = iov->iov_base + iov_ofs;
1374 unsigned len;
1375 size_t left;
1376
1377 len = iov->iov_len - iov_ofs;
1378 if (len > bytes)
1379 len = bytes;
1380 left = __copy_from_user_inatomic(vaddr, buf, len);
1381 total += len;
1382 bytes -= len;
1383 vaddr += len;
1384 if (unlikely(left)) {
1385 /*
1386 * Zero the rest of the target like __copy_from_user().
1387 */
1388 memset(vaddr, 0, bytes);
1389 total -= left;
1390 break;
1391 }
1392 if (!bytes)
1393 break;
1394 iov++;
1395 iov_ofs = 0;
1396 }
1397 return total;
1398}
1399
1400static inline void ntfs_set_next_iovec(const struct iovec **iovp,
1401 size_t *iov_ofsp, size_t bytes)
1402{
1403 const struct iovec *iov = *iovp;
1404 size_t iov_ofs = *iov_ofsp;
1405
1406 while (bytes) {
1407 unsigned len;
1408
1409 len = iov->iov_len - iov_ofs;
1410 if (len > bytes)
1411 len = bytes;
1412 bytes -= len;
1413 iov_ofs += len;
1414 if (iov->iov_len == iov_ofs) {
1415 iov++;
1416 iov_ofs = 0;
1417 }
1418 }
1419 *iovp = iov;
1420 *iov_ofsp = iov_ofs;
1421}
1422
1423/*
1424 * This has the same side-effects and return value as ntfs_copy_from_user().
1425 * The difference is that on a fault we need to memset the remainder of the
1426 * pages (out to offset + bytes), to emulate ntfs_copy_from_user()'s
1427 * single-segment behaviour.
1428 *
1429 * We call the same helper (__ntfs_copy_from_user_iovec()) both when atomic and
1430 * when not atomic. This is ok because __ntfs_copy_from_user_iovec() calls
1431 * __copy_from_user_inatomic() and it is ok to call this when non-atomic. In
1432 * fact, the only difference between __copy_from_user_inatomic() and
1433 * __copy_from_user() is that the latter calls might_sleep(). And on many
1434 * architectures __copy_from_user_inatomic() is just defined to
1435 * __copy_from_user() so it makes no difference at all on those architectures.
1436 */
1437static inline size_t ntfs_copy_from_user_iovec(struct page **pages,
1438 unsigned nr_pages, unsigned ofs, const struct iovec **iov,
1439 size_t *iov_ofs, size_t bytes)
1440{
1441 struct page **last_page = pages + nr_pages;
1442 char *kaddr;
1443 size_t copied, len, total = 0;
1444
1445 do {
1446 len = PAGE_CACHE_SIZE - ofs;
1447 if (len > bytes)
1448 len = bytes;
1449 kaddr = kmap_atomic(*pages, KM_USER0);
1450 copied = __ntfs_copy_from_user_iovec(kaddr + ofs,
1451 *iov, *iov_ofs, len);
1452 kunmap_atomic(kaddr, KM_USER0);
1453 if (unlikely(copied != len)) {
1454 /* Do it the slow way. */
1455 kaddr = kmap(*pages);
1456 copied = __ntfs_copy_from_user_iovec(kaddr + ofs,
1457 *iov, *iov_ofs, len);
1458 kunmap(*pages);
1459 if (unlikely(copied != len))
1460 goto err_out;
1461 }
1462 total += len;
1463 bytes -= len;
1464 if (!bytes)
1465 break;
1466 ntfs_set_next_iovec(iov, iov_ofs, len);
1467 ofs = 0;
1468 } while (++pages < last_page);
1469out:
1470 return total;
1471err_out:
1472 total += copied;
1473 /* Zero the rest of the target like __copy_from_user(). */
1474 while (++pages < last_page) {
1475 bytes -= len;
1476 if (!bytes)
1477 break;
1478 len = PAGE_CACHE_SIZE;
1479 if (len > bytes)
1480 len = bytes;
1481 kaddr = kmap_atomic(*pages, KM_USER0);
1482 memset(kaddr, 0, len);
1483 kunmap_atomic(kaddr, KM_USER0);
1484 }
1485 goto out;
1486}
1487
1488static inline void ntfs_flush_dcache_pages(struct page **pages,
1489 unsigned nr_pages)
1490{
1491 BUG_ON(!nr_pages);
1492 do {
1493 /*
1494 * Warning: Do not do the decrement at the same time as the
1495 * call because flush_dcache_page() is a NULL macro on i386
1496 * and hence the decrement never happens.
1497 */
1498 flush_dcache_page(pages[nr_pages]);
1499 } while (--nr_pages > 0);
1500}
1501
1502/**
1503 * ntfs_commit_pages_after_non_resident_write - commit the received data
1504 * @pages: array of destination pages
1505 * @nr_pages: number of pages in @pages
1506 * @pos: byte position in file at which the write begins
1507 * @bytes: number of bytes to be written
1508 *
1509 * See description of ntfs_commit_pages_after_write(), below.
1510 */
1511static inline int ntfs_commit_pages_after_non_resident_write(
1512 struct page **pages, const unsigned nr_pages,
1513 s64 pos, size_t bytes)
1514{
1515 s64 end, initialized_size;
1516 struct inode *vi;
1517 ntfs_inode *ni, *base_ni;
1518 struct buffer_head *bh, *head;
1519 ntfs_attr_search_ctx *ctx;
1520 MFT_RECORD *m;
1521 ATTR_RECORD *a;
1522 unsigned long flags;
1523 unsigned blocksize, u;
1524 int err;
1525
1526 vi = pages[0]->mapping->host;
1527 ni = NTFS_I(vi);
1528 blocksize = 1 << vi->i_blkbits;
1529 end = pos + bytes;
1530 u = 0;
1531 do {
1532 s64 bh_pos;
1533 struct page *page;
1534 BOOL partial;
1535
1536 page = pages[u];
1537 bh_pos = (s64)page->index << PAGE_CACHE_SHIFT;
1538 bh = head = page_buffers(page);
1539 partial = FALSE;
1540 do {
1541 s64 bh_end;
1542
1543 bh_end = bh_pos + blocksize;
1544 if (bh_end <= pos || bh_pos >= end) {
1545 if (!buffer_uptodate(bh))
1546 partial = TRUE;
1547 } else {
1548 set_buffer_uptodate(bh);
1549 mark_buffer_dirty(bh);
1550 }
1551 } while (bh_pos += blocksize, (bh = bh->b_this_page) != head);
1552 /*
1553 * If all buffers are now uptodate but the page is not, set the
1554 * page uptodate.
1555 */
1556 if (!partial && !PageUptodate(page))
1557 SetPageUptodate(page);
1558 } while (++u < nr_pages);
1559 /*
1560 * Finally, if we do not need to update initialized_size or i_size we
1561 * are finished.
1562 */
1563 read_lock_irqsave(&ni->size_lock, flags);
1564 initialized_size = ni->initialized_size;
1565 read_unlock_irqrestore(&ni->size_lock, flags);
1566 if (end <= initialized_size) {
1567 ntfs_debug("Done.");
1568 return 0;
1569 }
1570 /*
1571 * Update initialized_size/i_size as appropriate, both in the inode and
1572 * the mft record.
1573 */
1574 if (!NInoAttr(ni))
1575 base_ni = ni;
1576 else
1577 base_ni = ni->ext.base_ntfs_ino;
1578 /* Map, pin, and lock the mft record. */
1579 m = map_mft_record(base_ni);
1580 if (IS_ERR(m)) {
1581 err = PTR_ERR(m);
1582 m = NULL;
1583 ctx = NULL;
1584 goto err_out;
1585 }
1586 BUG_ON(!NInoNonResident(ni));
1587 ctx = ntfs_attr_get_search_ctx(base_ni, m);
1588 if (unlikely(!ctx)) {
1589 err = -ENOMEM;
1590 goto err_out;
1591 }
1592 err = ntfs_attr_lookup(ni->type, ni->name, ni->name_len,
1593 CASE_SENSITIVE, 0, NULL, 0, ctx);
1594 if (unlikely(err)) {
1595 if (err == -ENOENT)
1596 err = -EIO;
1597 goto err_out;
1598 }
1599 a = ctx->attr;
1600 BUG_ON(!a->non_resident);
1601 write_lock_irqsave(&ni->size_lock, flags);
1602 BUG_ON(end > ni->allocated_size);
1603 ni->initialized_size = end;
1604 a->data.non_resident.initialized_size = cpu_to_sle64(end);
1605 if (end > i_size_read(vi)) {
1606 i_size_write(vi, end);
1607 a->data.non_resident.data_size =
1608 a->data.non_resident.initialized_size;
1609 }
1610 write_unlock_irqrestore(&ni->size_lock, flags);
1611 /* Mark the mft record dirty, so it gets written back. */
1612 flush_dcache_mft_record_page(ctx->ntfs_ino);
1613 mark_mft_record_dirty(ctx->ntfs_ino);
1614 ntfs_attr_put_search_ctx(ctx);
1615 unmap_mft_record(base_ni);
1616 ntfs_debug("Done.");
1617 return 0;
1618err_out:
1619 if (ctx)
1620 ntfs_attr_put_search_ctx(ctx);
1621 if (m)
1622 unmap_mft_record(base_ni);
1623 ntfs_error(vi->i_sb, "Failed to update initialized_size/i_size (error "
1624 "code %i).", err);
1625 if (err != -ENOMEM) {
1626 NVolSetErrors(ni->vol);
1627 make_bad_inode(VFS_I(base_ni));
1628 make_bad_inode(vi);
1629 }
1630 return err;
1631}
1632
1633/**
1634 * ntfs_commit_pages_after_write - commit the received data
1635 * @pages: array of destination pages
1636 * @nr_pages: number of pages in @pages
1637 * @pos: byte position in file at which the write begins
1638 * @bytes: number of bytes to be written
1639 *
1640 * This is called from ntfs_file_buffered_write() with i_sem held on the inode
1641 * (@pages[0]->mapping->host). There are @nr_pages pages in @pages which are
1642 * locked but not kmap()ped. The source data has already been copied into the
1643 * @page. ntfs_prepare_pages_for_non_resident_write() has been called before
1644 * the data was copied (for non-resident attributes only) and it returned
1645 * success.
1646 *
1647 * Need to set uptodate and mark dirty all buffers within the boundary of the
1648 * write. If all buffers in a page are uptodate we set the page uptodate, too.
1649 *
1650 * Setting the buffers dirty ensures that they get written out later when
1651 * ntfs_writepage() is invoked by the VM.
1652 *
1653 * Finally, we need to update i_size and initialized_size as appropriate both
1654 * in the inode and the mft record.
1655 *
1656 * This is modelled after fs/buffer.c::generic_commit_write(), which marks
1657 * buffers uptodate and dirty, sets the page uptodate if all buffers in the
1658 * page are uptodate, and updates i_size if the end of io is beyond i_size. In
1659 * that case, it also marks the inode dirty.
1660 *
1661 * If things have gone as outlined in
1662 * ntfs_prepare_pages_for_non_resident_write(), we do not need to do any page
1663 * content modifications here for non-resident attributes. For resident
1664 * attributes we need to do the uptodate bringing here which we combine with
1665 * the copying into the mft record which means we save one atomic kmap.
1666 *
1667 * Return 0 on success or -errno on error.
1668 */
1669static int ntfs_commit_pages_after_write(struct page **pages,
1670 const unsigned nr_pages, s64 pos, size_t bytes)
1671{
1672 s64 end, initialized_size;
1673 loff_t i_size;
1674 struct inode *vi;
1675 ntfs_inode *ni, *base_ni;
1676 struct page *page;
1677 ntfs_attr_search_ctx *ctx;
1678 MFT_RECORD *m;
1679 ATTR_RECORD *a;
1680 char *kattr, *kaddr;
1681 unsigned long flags;
1682 u32 attr_len;
1683 int err;
1684
1685 BUG_ON(!nr_pages);
1686 BUG_ON(!pages);
1687 page = pages[0];
1688 BUG_ON(!page);
1689 vi = page->mapping->host;
1690 ni = NTFS_I(vi);
1691 ntfs_debug("Entering for inode 0x%lx, attribute type 0x%x, start page "
Anton Altaparmakovd04bd1f2005-10-24 08:41:24 +01001692 "index 0x%lx, nr_pages 0x%x, pos 0x%llx, bytes 0x%zx.",
Anton Altaparmakov98b27032005-10-11 15:40:40 +01001693 vi->i_ino, ni->type, page->index, nr_pages,
1694 (long long)pos, bytes);
1695 if (NInoNonResident(ni))
1696 return ntfs_commit_pages_after_non_resident_write(pages,
1697 nr_pages, pos, bytes);
1698 BUG_ON(nr_pages > 1);
1699 /*
1700 * Attribute is resident, implying it is not compressed, encrypted, or
1701 * sparse.
1702 */
1703 if (!NInoAttr(ni))
1704 base_ni = ni;
1705 else
1706 base_ni = ni->ext.base_ntfs_ino;
1707 BUG_ON(NInoNonResident(ni));
1708 /* Map, pin, and lock the mft record. */
1709 m = map_mft_record(base_ni);
1710 if (IS_ERR(m)) {
1711 err = PTR_ERR(m);
1712 m = NULL;
1713 ctx = NULL;
1714 goto err_out;
1715 }
1716 ctx = ntfs_attr_get_search_ctx(base_ni, m);
1717 if (unlikely(!ctx)) {
1718 err = -ENOMEM;
1719 goto err_out;
1720 }
1721 err = ntfs_attr_lookup(ni->type, ni->name, ni->name_len,
1722 CASE_SENSITIVE, 0, NULL, 0, ctx);
1723 if (unlikely(err)) {
1724 if (err == -ENOENT)
1725 err = -EIO;
1726 goto err_out;
1727 }
1728 a = ctx->attr;
1729 BUG_ON(a->non_resident);
1730 /* The total length of the attribute value. */
1731 attr_len = le32_to_cpu(a->data.resident.value_length);
1732 i_size = i_size_read(vi);
1733 BUG_ON(attr_len != i_size);
1734 BUG_ON(pos > attr_len);
1735 end = pos + bytes;
1736 BUG_ON(end > le32_to_cpu(a->length) -
1737 le16_to_cpu(a->data.resident.value_offset));
1738 kattr = (u8*)a + le16_to_cpu(a->data.resident.value_offset);
1739 kaddr = kmap_atomic(page, KM_USER0);
1740 /* Copy the received data from the page to the mft record. */
1741 memcpy(kattr + pos, kaddr + pos, bytes);
1742 /* Update the attribute length if necessary. */
1743 if (end > attr_len) {
1744 attr_len = end;
1745 a->data.resident.value_length = cpu_to_le32(attr_len);
1746 }
1747 /*
1748 * If the page is not uptodate, bring the out of bounds area(s)
1749 * uptodate by copying data from the mft record to the page.
1750 */
1751 if (!PageUptodate(page)) {
1752 if (pos > 0)
1753 memcpy(kaddr, kattr, pos);
1754 if (end < attr_len)
1755 memcpy(kaddr + end, kattr + end, attr_len - end);
1756 /* Zero the region outside the end of the attribute value. */
1757 memset(kaddr + attr_len, 0, PAGE_CACHE_SIZE - attr_len);
1758 flush_dcache_page(page);
1759 SetPageUptodate(page);
1760 }
1761 kunmap_atomic(kaddr, KM_USER0);
1762 /* Update initialized_size/i_size if necessary. */
1763 read_lock_irqsave(&ni->size_lock, flags);
1764 initialized_size = ni->initialized_size;
1765 BUG_ON(end > ni->allocated_size);
1766 read_unlock_irqrestore(&ni->size_lock, flags);
1767 BUG_ON(initialized_size != i_size);
1768 if (end > initialized_size) {
1769 unsigned long flags;
1770
1771 write_lock_irqsave(&ni->size_lock, flags);
1772 ni->initialized_size = end;
1773 i_size_write(vi, end);
1774 write_unlock_irqrestore(&ni->size_lock, flags);
1775 }
1776 /* Mark the mft record dirty, so it gets written back. */
1777 flush_dcache_mft_record_page(ctx->ntfs_ino);
1778 mark_mft_record_dirty(ctx->ntfs_ino);
1779 ntfs_attr_put_search_ctx(ctx);
1780 unmap_mft_record(base_ni);
1781 ntfs_debug("Done.");
1782 return 0;
1783err_out:
1784 if (err == -ENOMEM) {
1785 ntfs_warning(vi->i_sb, "Error allocating memory required to "
1786 "commit the write.");
1787 if (PageUptodate(page)) {
1788 ntfs_warning(vi->i_sb, "Page is uptodate, setting "
1789 "dirty so the write will be retried "
1790 "later on by the VM.");
1791 /*
1792 * Put the page on mapping->dirty_pages, but leave its
1793 * buffers' dirty state as-is.
1794 */
1795 __set_page_dirty_nobuffers(page);
1796 err = 0;
1797 } else
1798 ntfs_error(vi->i_sb, "Page is not uptodate. Written "
1799 "data has been lost.");
1800 } else {
1801 ntfs_error(vi->i_sb, "Resident attribute commit write failed "
1802 "with error %i.", err);
1803 NVolSetErrors(ni->vol);
1804 make_bad_inode(VFS_I(base_ni));
1805 make_bad_inode(vi);
1806 }
1807 if (ctx)
1808 ntfs_attr_put_search_ctx(ctx);
1809 if (m)
1810 unmap_mft_record(base_ni);
1811 return err;
1812}
1813
1814/**
1815 * ntfs_file_buffered_write -
1816 *
1817 * Locking: The vfs is holding ->i_sem on the inode.
1818 */
1819static ssize_t ntfs_file_buffered_write(struct kiocb *iocb,
1820 const struct iovec *iov, unsigned long nr_segs,
1821 loff_t pos, loff_t *ppos, size_t count)
1822{
1823 struct file *file = iocb->ki_filp;
1824 struct address_space *mapping = file->f_mapping;
1825 struct inode *vi = mapping->host;
1826 ntfs_inode *ni = NTFS_I(vi);
1827 ntfs_volume *vol = ni->vol;
1828 struct page *pages[NTFS_MAX_PAGES_PER_CLUSTER];
1829 struct page *cached_page = NULL;
1830 char __user *buf = NULL;
1831 s64 end, ll;
1832 VCN last_vcn;
1833 LCN lcn;
1834 unsigned long flags;
Anton Altaparmakovdda65b92005-10-24 08:57:59 +01001835 size_t bytes, iov_ofs = 0; /* Offset in the current iovec. */
Anton Altaparmakov98b27032005-10-11 15:40:40 +01001836 ssize_t status, written;
1837 unsigned nr_pages;
1838 int err;
1839 struct pagevec lru_pvec;
1840
1841 ntfs_debug("Entering for i_ino 0x%lx, attribute type 0x%x, "
1842 "pos 0x%llx, count 0x%lx.",
1843 vi->i_ino, (unsigned)le32_to_cpu(ni->type),
1844 (unsigned long long)pos, (unsigned long)count);
1845 if (unlikely(!count))
1846 return 0;
1847 BUG_ON(NInoMstProtected(ni));
1848 /*
1849 * If the attribute is not an index root and it is encrypted or
1850 * compressed, we cannot write to it yet. Note we need to check for
1851 * AT_INDEX_ALLOCATION since this is the type of both directory and
1852 * index inodes.
1853 */
1854 if (ni->type != AT_INDEX_ALLOCATION) {
1855 /* If file is encrypted, deny access, just like NT4. */
1856 if (NInoEncrypted(ni)) {
Anton Altaparmakov7d0ffdb2005-10-19 12:21:19 +01001857 /*
1858 * Reminder for later: Encrypted files are _always_
1859 * non-resident so that the content can always be
1860 * encrypted.
1861 */
Anton Altaparmakov98b27032005-10-11 15:40:40 +01001862 ntfs_debug("Denying write access to encrypted file.");
1863 return -EACCES;
1864 }
1865 if (NInoCompressed(ni)) {
Anton Altaparmakov7d0ffdb2005-10-19 12:21:19 +01001866 /* Only unnamed $DATA attribute can be compressed. */
1867 BUG_ON(ni->type != AT_DATA);
1868 BUG_ON(ni->name_len);
1869 /*
1870 * Reminder for later: If resident, the data is not
1871 * actually compressed. Only on the switch to non-
1872 * resident does compression kick in. This is in
1873 * contrast to encrypted files (see above).
1874 */
Anton Altaparmakov98b27032005-10-11 15:40:40 +01001875 ntfs_error(vi->i_sb, "Writing to compressed files is "
1876 "not implemented yet. Sorry.");
1877 return -EOPNOTSUPP;
1878 }
1879 }
1880 /*
1881 * If a previous ntfs_truncate() failed, repeat it and abort if it
1882 * fails again.
1883 */
1884 if (unlikely(NInoTruncateFailed(ni))) {
1885 down_write(&vi->i_alloc_sem);
1886 err = ntfs_truncate(vi);
1887 up_write(&vi->i_alloc_sem);
1888 if (err || NInoTruncateFailed(ni)) {
1889 if (!err)
1890 err = -EIO;
1891 ntfs_error(vol->sb, "Cannot perform write to inode "
1892 "0x%lx, attribute type 0x%x, because "
1893 "ntfs_truncate() failed (error code "
1894 "%i).", vi->i_ino,
1895 (unsigned)le32_to_cpu(ni->type), err);
1896 return err;
1897 }
1898 }
1899 /* The first byte after the write. */
1900 end = pos + count;
1901 /*
1902 * If the write goes beyond the allocated size, extend the allocation
1903 * to cover the whole of the write, rounded up to the nearest cluster.
1904 */
1905 read_lock_irqsave(&ni->size_lock, flags);
1906 ll = ni->allocated_size;
1907 read_unlock_irqrestore(&ni->size_lock, flags);
1908 if (end > ll) {
1909 /* Extend the allocation without changing the data size. */
1910 ll = ntfs_attr_extend_allocation(ni, end, -1, pos);
1911 if (likely(ll >= 0)) {
1912 BUG_ON(pos >= ll);
1913 /* If the extension was partial truncate the write. */
1914 if (end > ll) {
1915 ntfs_debug("Truncating write to inode 0x%lx, "
1916 "attribute type 0x%x, because "
1917 "the allocation was only "
1918 "partially extended.",
1919 vi->i_ino, (unsigned)
1920 le32_to_cpu(ni->type));
1921 end = ll;
1922 count = ll - pos;
1923 }
1924 } else {
1925 err = ll;
1926 read_lock_irqsave(&ni->size_lock, flags);
1927 ll = ni->allocated_size;
1928 read_unlock_irqrestore(&ni->size_lock, flags);
1929 /* Perform a partial write if possible or fail. */
1930 if (pos < ll) {
1931 ntfs_debug("Truncating write to inode 0x%lx, "
1932 "attribute type 0x%x, because "
1933 "extending the allocation "
1934 "failed (error code %i).",
1935 vi->i_ino, (unsigned)
1936 le32_to_cpu(ni->type), err);
1937 end = ll;
1938 count = ll - pos;
1939 } else {
1940 ntfs_error(vol->sb, "Cannot perform write to "
1941 "inode 0x%lx, attribute type "
1942 "0x%x, because extending the "
1943 "allocation failed (error "
1944 "code %i).", vi->i_ino,
1945 (unsigned)
1946 le32_to_cpu(ni->type), err);
1947 return err;
1948 }
1949 }
1950 }
1951 pagevec_init(&lru_pvec, 0);
1952 written = 0;
1953 /*
1954 * If the write starts beyond the initialized size, extend it up to the
1955 * beginning of the write and initialize all non-sparse space between
1956 * the old initialized size and the new one. This automatically also
1957 * increments the vfs inode->i_size to keep it above or equal to the
1958 * initialized_size.
1959 */
1960 read_lock_irqsave(&ni->size_lock, flags);
1961 ll = ni->initialized_size;
1962 read_unlock_irqrestore(&ni->size_lock, flags);
1963 if (pos > ll) {
1964 err = ntfs_attr_extend_initialized(ni, pos, &cached_page,
1965 &lru_pvec);
1966 if (err < 0) {
1967 ntfs_error(vol->sb, "Cannot perform write to inode "
1968 "0x%lx, attribute type 0x%x, because "
1969 "extending the initialized size "
1970 "failed (error code %i).", vi->i_ino,
1971 (unsigned)le32_to_cpu(ni->type), err);
1972 status = err;
1973 goto err_out;
1974 }
1975 }
1976 /*
1977 * Determine the number of pages per cluster for non-resident
1978 * attributes.
1979 */
1980 nr_pages = 1;
1981 if (vol->cluster_size > PAGE_CACHE_SIZE && NInoNonResident(ni))
1982 nr_pages = vol->cluster_size >> PAGE_CACHE_SHIFT;
1983 /* Finally, perform the actual write. */
1984 last_vcn = -1;
1985 if (likely(nr_segs == 1))
1986 buf = iov->iov_base;
Anton Altaparmakov98b27032005-10-11 15:40:40 +01001987 do {
1988 VCN vcn;
1989 pgoff_t idx, start_idx;
1990 unsigned ofs, do_pages, u;
1991 size_t copied;
1992
1993 start_idx = idx = pos >> PAGE_CACHE_SHIFT;
1994 ofs = pos & ~PAGE_CACHE_MASK;
1995 bytes = PAGE_CACHE_SIZE - ofs;
1996 do_pages = 1;
1997 if (nr_pages > 1) {
1998 vcn = pos >> vol->cluster_size_bits;
1999 if (vcn != last_vcn) {
2000 last_vcn = vcn;
2001 /*
2002 * Get the lcn of the vcn the write is in. If
2003 * it is a hole, need to lock down all pages in
2004 * the cluster.
2005 */
2006 down_read(&ni->runlist.lock);
2007 lcn = ntfs_attr_vcn_to_lcn_nolock(ni, pos >>
2008 vol->cluster_size_bits, FALSE);
2009 up_read(&ni->runlist.lock);
2010 if (unlikely(lcn < LCN_HOLE)) {
2011 status = -EIO;
2012 if (lcn == LCN_ENOMEM)
2013 status = -ENOMEM;
2014 else
2015 ntfs_error(vol->sb, "Cannot "
2016 "perform write to "
2017 "inode 0x%lx, "
2018 "attribute type 0x%x, "
2019 "because the attribute "
2020 "is corrupt.",
2021 vi->i_ino, (unsigned)
2022 le32_to_cpu(ni->type));
2023 break;
2024 }
2025 if (lcn == LCN_HOLE) {
2026 start_idx = (pos & ~(s64)
2027 vol->cluster_size_mask)
2028 >> PAGE_CACHE_SHIFT;
2029 bytes = vol->cluster_size - (pos &
2030 vol->cluster_size_mask);
2031 do_pages = nr_pages;
2032 }
2033 }
2034 }
2035 if (bytes > count)
2036 bytes = count;
2037 /*
2038 * Bring in the user page(s) that we will copy from _first_.
2039 * Otherwise there is a nasty deadlock on copying from the same
2040 * page(s) as we are writing to, without it/them being marked
2041 * up-to-date. Note, at present there is nothing to stop the
2042 * pages being swapped out between us bringing them into memory
2043 * and doing the actual copying.
2044 */
2045 if (likely(nr_segs == 1))
2046 ntfs_fault_in_pages_readable(buf, bytes);
2047 else
2048 ntfs_fault_in_pages_readable_iovec(iov, iov_ofs, bytes);
2049 /* Get and lock @do_pages starting at index @start_idx. */
2050 status = __ntfs_grab_cache_pages(mapping, start_idx, do_pages,
2051 pages, &cached_page, &lru_pvec);
2052 if (unlikely(status))
2053 break;
2054 /*
2055 * For non-resident attributes, we need to fill any holes with
2056 * actual clusters and ensure all bufferes are mapped. We also
2057 * need to bring uptodate any buffers that are only partially
2058 * being written to.
2059 */
2060 if (NInoNonResident(ni)) {
2061 status = ntfs_prepare_pages_for_non_resident_write(
2062 pages, do_pages, pos, bytes);
2063 if (unlikely(status)) {
2064 loff_t i_size;
2065
2066 do {
2067 unlock_page(pages[--do_pages]);
2068 page_cache_release(pages[do_pages]);
2069 } while (do_pages);
2070 /*
2071 * The write preparation may have instantiated
2072 * allocated space outside i_size. Trim this
2073 * off again. We can ignore any errors in this
2074 * case as we will just be waisting a bit of
2075 * allocated space, which is not a disaster.
2076 */
2077 i_size = i_size_read(vi);
2078 if (pos + bytes > i_size)
2079 vmtruncate(vi, i_size);
2080 break;
2081 }
2082 }
2083 u = (pos >> PAGE_CACHE_SHIFT) - pages[0]->index;
2084 if (likely(nr_segs == 1)) {
2085 copied = ntfs_copy_from_user(pages + u, do_pages - u,
2086 ofs, buf, bytes);
2087 buf += copied;
2088 } else
2089 copied = ntfs_copy_from_user_iovec(pages + u,
2090 do_pages - u, ofs, &iov, &iov_ofs,
2091 bytes);
2092 ntfs_flush_dcache_pages(pages + u, do_pages - u);
2093 status = ntfs_commit_pages_after_write(pages, do_pages, pos,
2094 bytes);
2095 if (likely(!status)) {
2096 written += copied;
2097 count -= copied;
2098 pos += copied;
2099 if (unlikely(copied != bytes))
2100 status = -EFAULT;
2101 }
2102 do {
2103 unlock_page(pages[--do_pages]);
2104 mark_page_accessed(pages[do_pages]);
2105 page_cache_release(pages[do_pages]);
2106 } while (do_pages);
2107 if (unlikely(status))
2108 break;
2109 balance_dirty_pages_ratelimited(mapping);
2110 cond_resched();
2111 } while (count);
2112err_out:
2113 *ppos = pos;
2114 if (cached_page)
2115 page_cache_release(cached_page);
2116 /* For now, when the user asks for O_SYNC, we actually give O_DSYNC. */
2117 if (likely(!status)) {
2118 if (unlikely((file->f_flags & O_SYNC) || IS_SYNC(vi))) {
2119 if (!mapping->a_ops->writepage || !is_sync_kiocb(iocb))
2120 status = generic_osync_inode(vi, mapping,
2121 OSYNC_METADATA|OSYNC_DATA);
2122 }
2123 }
2124 pagevec_lru_add(&lru_pvec);
2125 ntfs_debug("Done. Returning %s (written 0x%lx, status %li).",
2126 written ? "written" : "status", (unsigned long)written,
2127 (long)status);
2128 return written ? written : status;
2129}
2130
2131/**
2132 * ntfs_file_aio_write_nolock -
2133 */
2134static ssize_t ntfs_file_aio_write_nolock(struct kiocb *iocb,
2135 const struct iovec *iov, unsigned long nr_segs, loff_t *ppos)
2136{
2137 struct file *file = iocb->ki_filp;
2138 struct address_space *mapping = file->f_mapping;
2139 struct inode *inode = mapping->host;
2140 loff_t pos;
2141 unsigned long seg;
2142 size_t count; /* after file limit checks */
2143 ssize_t written, err;
2144
2145 count = 0;
2146 for (seg = 0; seg < nr_segs; seg++) {
2147 const struct iovec *iv = &iov[seg];
2148 /*
2149 * If any segment has a negative length, or the cumulative
2150 * length ever wraps negative then return -EINVAL.
2151 */
2152 count += iv->iov_len;
2153 if (unlikely((ssize_t)(count|iv->iov_len) < 0))
2154 return -EINVAL;
2155 if (access_ok(VERIFY_READ, iv->iov_base, iv->iov_len))
2156 continue;
2157 if (!seg)
2158 return -EFAULT;
2159 nr_segs = seg;
2160 count -= iv->iov_len; /* This segment is no good */
2161 break;
2162 }
2163 pos = *ppos;
2164 vfs_check_frozen(inode->i_sb, SB_FREEZE_WRITE);
2165 /* We can write back this queue in page reclaim. */
2166 current->backing_dev_info = mapping->backing_dev_info;
2167 written = 0;
2168 err = generic_write_checks(file, &pos, &count, S_ISBLK(inode->i_mode));
2169 if (err)
2170 goto out;
2171 if (!count)
2172 goto out;
2173 err = remove_suid(file->f_dentry);
2174 if (err)
2175 goto out;
2176 inode_update_time(inode, 1);
2177 written = ntfs_file_buffered_write(iocb, iov, nr_segs, pos, ppos,
2178 count);
2179out:
2180 current->backing_dev_info = NULL;
2181 return written ? written : err;
2182}
2183
2184/**
2185 * ntfs_file_aio_write -
2186 */
2187static ssize_t ntfs_file_aio_write(struct kiocb *iocb, const char __user *buf,
2188 size_t count, loff_t pos)
2189{
2190 struct file *file = iocb->ki_filp;
2191 struct address_space *mapping = file->f_mapping;
2192 struct inode *inode = mapping->host;
2193 ssize_t ret;
2194 struct iovec local_iov = { .iov_base = (void __user *)buf,
2195 .iov_len = count };
2196
2197 BUG_ON(iocb->ki_pos != pos);
2198
2199 down(&inode->i_sem);
2200 ret = ntfs_file_aio_write_nolock(iocb, &local_iov, 1, &iocb->ki_pos);
2201 up(&inode->i_sem);
2202 if (ret > 0 && ((file->f_flags & O_SYNC) || IS_SYNC(inode))) {
2203 int err = sync_page_range(inode, mapping, pos, ret);
2204 if (err < 0)
2205 ret = err;
2206 }
2207 return ret;
2208}
2209
2210/**
2211 * ntfs_file_writev -
2212 *
2213 * Basically the same as generic_file_writev() except that it ends up calling
2214 * ntfs_file_aio_write_nolock() instead of __generic_file_aio_write_nolock().
2215 */
2216static ssize_t ntfs_file_writev(struct file *file, const struct iovec *iov,
2217 unsigned long nr_segs, loff_t *ppos)
2218{
2219 struct address_space *mapping = file->f_mapping;
2220 struct inode *inode = mapping->host;
2221 struct kiocb kiocb;
2222 ssize_t ret;
2223
2224 down(&inode->i_sem);
2225 init_sync_kiocb(&kiocb, file);
2226 ret = ntfs_file_aio_write_nolock(&kiocb, iov, nr_segs, ppos);
2227 if (ret == -EIOCBQUEUED)
2228 ret = wait_on_sync_kiocb(&kiocb);
2229 up(&inode->i_sem);
2230 if (ret > 0 && ((file->f_flags & O_SYNC) || IS_SYNC(inode))) {
2231 int err = sync_page_range(inode, mapping, *ppos - ret, ret);
2232 if (err < 0)
2233 ret = err;
2234 }
2235 return ret;
2236}
2237
2238/**
2239 * ntfs_file_write - simple wrapper for ntfs_file_writev()
2240 */
2241static ssize_t ntfs_file_write(struct file *file, const char __user *buf,
2242 size_t count, loff_t *ppos)
2243{
2244 struct iovec local_iov = { .iov_base = (void __user *)buf,
2245 .iov_len = count };
2246
2247 return ntfs_file_writev(file, &local_iov, 1, ppos);
2248}
2249
2250/**
Linus Torvalds1da177e2005-04-16 15:20:36 -07002251 * ntfs_file_fsync - sync a file to disk
2252 * @filp: file to be synced
2253 * @dentry: dentry describing the file to sync
2254 * @datasync: if non-zero only flush user data and not metadata
2255 *
2256 * Data integrity sync of a file to disk. Used for fsync, fdatasync, and msync
2257 * system calls. This function is inspired by fs/buffer.c::file_fsync().
2258 *
2259 * If @datasync is false, write the mft record and all associated extent mft
2260 * records as well as the $DATA attribute and then sync the block device.
2261 *
2262 * If @datasync is true and the attribute is non-resident, we skip the writing
2263 * of the mft record and all associated extent mft records (this might still
2264 * happen due to the write_inode_now() call).
2265 *
2266 * Also, if @datasync is true, we do not wait on the inode to be written out
2267 * but we always wait on the page cache pages to be written out.
2268 *
2269 * Note: In the past @filp could be NULL so we ignore it as we don't need it
2270 * anyway.
2271 *
2272 * Locking: Caller must hold i_sem on the inode.
2273 *
2274 * TODO: We should probably also write all attribute/index inodes associated
2275 * with this inode but since we have no simple way of getting to them we ignore
2276 * this problem for now.
2277 */
2278static int ntfs_file_fsync(struct file *filp, struct dentry *dentry,
2279 int datasync)
2280{
2281 struct inode *vi = dentry->d_inode;
2282 int err, ret = 0;
2283
2284 ntfs_debug("Entering for inode 0x%lx.", vi->i_ino);
2285 BUG_ON(S_ISDIR(vi->i_mode));
2286 if (!datasync || !NInoNonResident(NTFS_I(vi)))
2287 ret = ntfs_write_inode(vi, 1);
2288 write_inode_now(vi, !datasync);
Anton Altaparmakovf25dfb52005-09-08 20:35:33 +01002289 /*
2290 * NOTE: If we were to use mapping->private_list (see ext2 and
2291 * fs/buffer.c) for dirty blocks then we could optimize the below to be
2292 * sync_mapping_buffers(vi->i_mapping).
2293 */
Linus Torvalds1da177e2005-04-16 15:20:36 -07002294 err = sync_blockdev(vi->i_sb->s_bdev);
2295 if (unlikely(err && !ret))
2296 ret = err;
2297 if (likely(!ret))
2298 ntfs_debug("Done.");
2299 else
2300 ntfs_warning(vi->i_sb, "Failed to f%ssync inode 0x%lx. Error "
2301 "%u.", datasync ? "data" : "", vi->i_ino, -ret);
2302 return ret;
2303}
2304
2305#endif /* NTFS_RW */
2306
2307struct file_operations ntfs_file_ops = {
Anton Altaparmakov98b27032005-10-11 15:40:40 +01002308 .llseek = generic_file_llseek, /* Seek inside file. */
2309 .read = generic_file_read, /* Read from file. */
2310 .aio_read = generic_file_aio_read, /* Async read from file. */
2311 .readv = generic_file_readv, /* Read from file. */
Linus Torvalds1da177e2005-04-16 15:20:36 -07002312#ifdef NTFS_RW
Anton Altaparmakov98b27032005-10-11 15:40:40 +01002313 .write = ntfs_file_write, /* Write to file. */
2314 .aio_write = ntfs_file_aio_write, /* Async write to file. */
2315 .writev = ntfs_file_writev, /* Write to file. */
2316 /*.release = ,*/ /* Last file is closed. See
2317 fs/ext2/file.c::
2318 ext2_release_file() for
2319 how to use this to discard
2320 preallocated space for
2321 write opened files. */
2322 .fsync = ntfs_file_fsync, /* Sync a file to disk. */
2323 /*.aio_fsync = ,*/ /* Sync all outstanding async
2324 i/o operations on a
2325 kiocb. */
Linus Torvalds1da177e2005-04-16 15:20:36 -07002326#endif /* NTFS_RW */
Anton Altaparmakov98b27032005-10-11 15:40:40 +01002327 /*.ioctl = ,*/ /* Perform function on the
2328 mounted filesystem. */
2329 .mmap = generic_file_mmap, /* Mmap file. */
2330 .open = ntfs_file_open, /* Open file. */
2331 .sendfile = generic_file_sendfile, /* Zero-copy data send with
2332 the data source being on
2333 the ntfs partition. We do
2334 not need to care about the
2335 data destination. */
2336 /*.sendpage = ,*/ /* Zero-copy data send with
2337 the data destination being
2338 on the ntfs partition. We
2339 do not need to care about
2340 the data source. */
Linus Torvalds1da177e2005-04-16 15:20:36 -07002341};
2342
2343struct inode_operations ntfs_file_inode_ops = {
2344#ifdef NTFS_RW
2345 .truncate = ntfs_truncate_vfs,
2346 .setattr = ntfs_setattr,
2347#endif /* NTFS_RW */
2348};
2349
2350struct file_operations ntfs_empty_file_ops = {};
2351
2352struct inode_operations ntfs_empty_inode_ops = {};