2 * attrib.c - NTFS attribute operations. Part of the Linux-NTFS project.
4 * Copyright (c) 2001-2005 Anton Altaparmakov
5 * Copyright (c) 2002 Richard Russon
7 * This program/include file is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU General Public License as published
9 * by the Free Software Foundation; either version 2 of the License, or
10 * (at your option) any later version.
12 * This program/include file is distributed in the hope that it will be
13 * useful, but WITHOUT ANY WARRANTY; without even the implied warranty
14 * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
17 * You should have received a copy of the GNU General Public License
18 * along with this program (in the main directory of the Linux-NTFS
19 * distribution in the file COPYING); if not, write to the Free Software
20 * Foundation,Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
23 #include <linux/buffer_head.h>
24 #include <linux/swap.h>
36 * ntfs_map_runlist_nolock - map (a part of) a runlist of an ntfs inode
37 * @ni: ntfs inode for which to map (part of) a runlist
38 * @vcn: map runlist part containing this vcn
40 * Map the part of a runlist containing the @vcn of the ntfs inode @ni.
42 * Return 0 on success and -errno on error.
44 * Locking: - The runlist must be locked for writing.
45 * - This function modifies the runlist.
47 int ntfs_map_runlist_nolock(ntfs_inode *ni, VCN vcn)
51 ntfs_attr_search_ctx *ctx;
55 ntfs_debug("Mapping runlist part containing vcn 0x%llx.",
56 (unsigned long long)vcn);
60 base_ni = ni->ext.base_ntfs_ino;
61 mrec = map_mft_record(base_ni);
64 ctx = ntfs_attr_get_search_ctx(base_ni, mrec);
69 err = ntfs_attr_lookup(ni->type, ni->name, ni->name_len,
70 CASE_SENSITIVE, vcn, NULL, 0, ctx);
72 rl = ntfs_mapping_pairs_decompress(ni->vol, ctx->attr,
79 ntfs_attr_put_search_ctx(ctx);
81 unmap_mft_record(base_ni);
86 * ntfs_map_runlist - map (a part of) a runlist of an ntfs inode
87 * @ni: ntfs inode for which to map (part of) a runlist
88 * @vcn: map runlist part containing this vcn
90 * Map the part of a runlist containing the @vcn of the ntfs inode @ni.
92 * Return 0 on success and -errno on error.
94 * Locking: - The runlist must be unlocked on entry and is unlocked on return.
95 * - This function takes the runlist lock for writing and modifies the
98 int ntfs_map_runlist(ntfs_inode *ni, VCN vcn)
102 down_write(&ni->runlist.lock);
103 /* Make sure someone else didn't do the work while we were sleeping. */
104 if (likely(ntfs_rl_vcn_to_lcn(ni->runlist.rl, vcn) <=
106 err = ntfs_map_runlist_nolock(ni, vcn);
107 up_write(&ni->runlist.lock);
112 * ntfs_attr_vcn_to_lcn_nolock - convert a vcn into a lcn given an ntfs inode
113 * @ni: ntfs inode of the attribute whose runlist to search
114 * @vcn: vcn to convert
115 * @write_locked: true if the runlist is locked for writing
117 * Find the virtual cluster number @vcn in the runlist of the ntfs attribute
118 * described by the ntfs inode @ni and return the corresponding logical cluster
121 * If the @vcn is not mapped yet, the attempt is made to map the attribute
122 * extent containing the @vcn and the vcn to lcn conversion is retried.
124 * If @write_locked is true the caller has locked the runlist for writing and
125 * if false for reading.
127 * Since lcns must be >= 0, we use negative return codes with special meaning:
129 * Return code Meaning / Description
130 * ==========================================
131 * LCN_HOLE Hole / not allocated on disk.
132 * LCN_ENOENT There is no such vcn in the runlist, i.e. @vcn is out of bounds.
133 * LCN_ENOMEM Not enough memory to map runlist.
134 * LCN_EIO Critical error (runlist/file is corrupt, i/o error, etc).
136 * Locking: - The runlist must be locked on entry and is left locked on return.
137 * - If @write_locked is FALSE, i.e. the runlist is locked for reading,
138 * the lock may be dropped inside the function so you cannot rely on
139 * the runlist still being the same when this function returns.
141 LCN ntfs_attr_vcn_to_lcn_nolock(ntfs_inode *ni, const VCN vcn,
142 const BOOL write_locked)
145 BOOL is_retry = FALSE;
147 ntfs_debug("Entering for i_ino 0x%lx, vcn 0x%llx, %s_locked.",
148 ni->mft_no, (unsigned long long)vcn,
149 write_locked ? "write" : "read");
151 BUG_ON(!NInoNonResident(ni));
154 /* Convert vcn to lcn. If that fails map the runlist and retry once. */
155 lcn = ntfs_rl_vcn_to_lcn(ni->runlist.rl, vcn);
156 if (likely(lcn >= LCN_HOLE)) {
157 ntfs_debug("Done, lcn 0x%llx.", (long long)lcn);
160 if (lcn != LCN_RL_NOT_MAPPED) {
161 if (lcn != LCN_ENOENT)
163 } else if (!is_retry) {
167 up_read(&ni->runlist.lock);
168 down_write(&ni->runlist.lock);
169 if (unlikely(ntfs_rl_vcn_to_lcn(ni->runlist.rl, vcn) !=
170 LCN_RL_NOT_MAPPED)) {
171 up_write(&ni->runlist.lock);
172 down_read(&ni->runlist.lock);
176 err = ntfs_map_runlist_nolock(ni, vcn);
178 up_write(&ni->runlist.lock);
179 down_read(&ni->runlist.lock);
187 else if (err == -ENOMEM)
192 if (lcn != LCN_ENOENT)
193 ntfs_error(ni->vol->sb, "Failed with error code %lli.",
199 * ntfs_attr_find_vcn_nolock - find a vcn in the runlist of an ntfs inode
200 * @ni: ntfs inode describing the runlist to search
202 * @write_locked: true if the runlist is locked for writing
204 * Find the virtual cluster number @vcn in the runlist described by the ntfs
205 * inode @ni and return the address of the runlist element containing the @vcn.
207 * If the @vcn is not mapped yet, the attempt is made to map the attribute
208 * extent containing the @vcn and the vcn to lcn conversion is retried.
210 * If @write_locked is true the caller has locked the runlist for writing and
211 * if false for reading.
213 * Note you need to distinguish between the lcn of the returned runlist element
214 * being >= 0 and LCN_HOLE. In the later case you have to return zeroes on
215 * read and allocate clusters on write.
217 * Return the runlist element containing the @vcn on success and
218 * ERR_PTR(-errno) on error. You need to test the return value with IS_ERR()
219 * to decide if the return is success or failure and PTR_ERR() to get to the
220 * error code if IS_ERR() is true.
222 * The possible error return codes are:
223 * -ENOENT - No such vcn in the runlist, i.e. @vcn is out of bounds.
224 * -ENOMEM - Not enough memory to map runlist.
225 * -EIO - Critical error (runlist/file is corrupt, i/o error, etc).
227 * Locking: - The runlist must be locked on entry and is left locked on return.
228 * - If @write_locked is FALSE, i.e. the runlist is locked for reading,
229 * the lock may be dropped inside the function so you cannot rely on
230 * the runlist still being the same when this function returns.
232 runlist_element *ntfs_attr_find_vcn_nolock(ntfs_inode *ni, const VCN vcn,
233 const BOOL write_locked)
237 BOOL is_retry = FALSE;
239 ntfs_debug("Entering for i_ino 0x%lx, vcn 0x%llx, %s_locked.",
240 ni->mft_no, (unsigned long long)vcn,
241 write_locked ? "write" : "read");
243 BUG_ON(!NInoNonResident(ni));
247 if (likely(rl && vcn >= rl[0].vcn)) {
248 while (likely(rl->length)) {
249 if (unlikely(vcn < rl[1].vcn)) {
250 if (likely(rl->lcn >= LCN_HOLE)) {
258 if (likely(rl->lcn != LCN_RL_NOT_MAPPED)) {
259 if (likely(rl->lcn == LCN_ENOENT))
265 if (!err && !is_retry) {
267 * The @vcn is in an unmapped region, map the runlist and
271 up_read(&ni->runlist.lock);
272 down_write(&ni->runlist.lock);
273 if (unlikely(ntfs_rl_vcn_to_lcn(ni->runlist.rl, vcn) !=
274 LCN_RL_NOT_MAPPED)) {
275 up_write(&ni->runlist.lock);
276 down_read(&ni->runlist.lock);
280 err = ntfs_map_runlist_nolock(ni, vcn);
282 up_write(&ni->runlist.lock);
283 down_read(&ni->runlist.lock);
290 * -EINVAL and -ENOENT coming from a failed mapping attempt are
291 * equivalent to i/o errors for us as they should not happen in
294 if (err == -EINVAL || err == -ENOENT)
299 ntfs_error(ni->vol->sb, "Failed with error code %i.", err);
304 * ntfs_attr_find - find (next) attribute in mft record
305 * @type: attribute type to find
306 * @name: attribute name to find (optional, i.e. NULL means don't care)
307 * @name_len: attribute name length (only needed if @name present)
308 * @ic: IGNORE_CASE or CASE_SENSITIVE (ignored if @name not present)
309 * @val: attribute value to find (optional, resident attributes only)
310 * @val_len: attribute value length
311 * @ctx: search context with mft record and attribute to search from
313 * You should not need to call this function directly. Use ntfs_attr_lookup()
316 * ntfs_attr_find() takes a search context @ctx as parameter and searches the
317 * mft record specified by @ctx->mrec, beginning at @ctx->attr, for an
318 * attribute of @type, optionally @name and @val.
320 * If the attribute is found, ntfs_attr_find() returns 0 and @ctx->attr will
321 * point to the found attribute.
323 * If the attribute is not found, ntfs_attr_find() returns -ENOENT and
324 * @ctx->attr will point to the attribute before which the attribute being
325 * searched for would need to be inserted if such an action were to be desired.
327 * On actual error, ntfs_attr_find() returns -EIO. In this case @ctx->attr is
328 * undefined and in particular do not rely on it not changing.
330 * If @ctx->is_first is TRUE, the search begins with @ctx->attr itself. If it
331 * is FALSE, the search begins after @ctx->attr.
333 * If @ic is IGNORE_CASE, the @name comparisson is not case sensitive and
334 * @ctx->ntfs_ino must be set to the ntfs inode to which the mft record
335 * @ctx->mrec belongs. This is so we can get at the ntfs volume and hence at
336 * the upcase table. If @ic is CASE_SENSITIVE, the comparison is case
337 * sensitive. When @name is present, @name_len is the @name length in Unicode
340 * If @name is not present (NULL), we assume that the unnamed attribute is
341 * being searched for.
343 * Finally, the resident attribute value @val is looked for, if present. If
344 * @val is not present (NULL), @val_len is ignored.
346 * ntfs_attr_find() only searches the specified mft record and it ignores the
347 * presence of an attribute list attribute (unless it is the one being searched
348 * for, obviously). If you need to take attribute lists into consideration,
349 * use ntfs_attr_lookup() instead (see below). This also means that you cannot
350 * use ntfs_attr_find() to search for extent records of non-resident
351 * attributes, as extents with lowest_vcn != 0 are usually described by the
352 * attribute list attribute only. - Note that it is possible that the first
353 * extent is only in the attribute list while the last extent is in the base
354 * mft record, so do not rely on being able to find the first extent in the
357 * Warning: Never use @val when looking for attribute types which can be
358 * non-resident as this most likely will result in a crash!
360 static int ntfs_attr_find(const ATTR_TYPE type, const ntfschar *name,
361 const u32 name_len, const IGNORE_CASE_BOOL ic,
362 const u8 *val, const u32 val_len, ntfs_attr_search_ctx *ctx)
365 ntfs_volume *vol = ctx->ntfs_ino->vol;
366 ntfschar *upcase = vol->upcase;
367 u32 upcase_len = vol->upcase_len;
370 * Iterate over attributes in mft record starting at @ctx->attr, or the
371 * attribute following that, if @ctx->is_first is TRUE.
375 ctx->is_first = FALSE;
377 a = (ATTR_RECORD*)((u8*)ctx->attr +
378 le32_to_cpu(ctx->attr->length));
379 for (;; a = (ATTR_RECORD*)((u8*)a + le32_to_cpu(a->length))) {
380 if ((u8*)a < (u8*)ctx->mrec || (u8*)a > (u8*)ctx->mrec +
381 le32_to_cpu(ctx->mrec->bytes_allocated))
384 if (unlikely(le32_to_cpu(a->type) > le32_to_cpu(type) ||
387 if (unlikely(!a->length))
392 * If @name is present, compare the two names. If @name is
393 * missing, assume we want an unnamed attribute.
396 /* The search failed if the found attribute is named. */
399 } else if (!ntfs_are_names_equal(name, name_len,
400 (ntfschar*)((u8*)a + le16_to_cpu(a->name_offset)),
401 a->name_length, ic, upcase, upcase_len)) {
404 rc = ntfs_collate_names(name, name_len,
406 le16_to_cpu(a->name_offset)),
407 a->name_length, 1, IGNORE_CASE,
410 * If @name collates before a->name, there is no
411 * matching attribute.
415 /* If the strings are not equal, continue search. */
418 rc = ntfs_collate_names(name, name_len,
420 le16_to_cpu(a->name_offset)),
421 a->name_length, 1, CASE_SENSITIVE,
429 * The names match or @name not present and attribute is
430 * unnamed. If no @val specified, we have found the attribute
435 /* @val is present; compare values. */
439 rc = memcmp(val, (u8*)a + le16_to_cpu(
440 a->data.resident.value_offset),
441 min_t(u32, val_len, le32_to_cpu(
442 a->data.resident.value_length)));
444 * If @val collates before the current attribute's
445 * value, there is no matching attribute.
451 a->data.resident.value_length);
460 ntfs_error(vol->sb, "Inode is corrupt. Run chkdsk.");
466 * load_attribute_list - load an attribute list into memory
467 * @vol: ntfs volume from which to read
468 * @runlist: runlist of the attribute list
469 * @al_start: destination buffer
470 * @size: size of the destination buffer in bytes
471 * @initialized_size: initialized size of the attribute list
473 * Walk the runlist @runlist and load all clusters from it copying them into
474 * the linear buffer @al. The maximum number of bytes copied to @al is @size
475 * bytes. Note, @size does not need to be a multiple of the cluster size. If
476 * @initialized_size is less than @size, the region in @al between
477 * @initialized_size and @size will be zeroed and not read from disk.
479 * Return 0 on success or -errno on error.
481 int load_attribute_list(ntfs_volume *vol, runlist *runlist, u8 *al_start,
482 const s64 size, const s64 initialized_size)
486 u8 *al_end = al + initialized_size;
488 struct buffer_head *bh;
489 struct super_block *sb;
490 unsigned long block_size;
491 unsigned long block, max_block;
493 unsigned char block_size_bits;
495 ntfs_debug("Entering.");
496 if (!vol || !runlist || !al || size <= 0 || initialized_size < 0 ||
497 initialized_size > size)
499 if (!initialized_size) {
504 block_size = sb->s_blocksize;
505 block_size_bits = sb->s_blocksize_bits;
506 down_read(&runlist->lock);
508 /* Read all clusters specified by the runlist one run at a time. */
510 lcn = ntfs_rl_vcn_to_lcn(rl, rl->vcn);
511 ntfs_debug("Reading vcn = 0x%llx, lcn = 0x%llx.",
512 (unsigned long long)rl->vcn,
513 (unsigned long long)lcn);
514 /* The attribute list cannot be sparse. */
516 ntfs_error(sb, "ntfs_rl_vcn_to_lcn() failed. Cannot "
517 "read attribute list.");
520 block = lcn << vol->cluster_size_bits >> block_size_bits;
521 /* Read the run from device in chunks of block_size bytes. */
522 max_block = block + (rl->length << vol->cluster_size_bits >>
524 ntfs_debug("max_block = 0x%lx.", max_block);
526 ntfs_debug("Reading block = 0x%lx.", block);
527 bh = sb_bread(sb, block);
529 ntfs_error(sb, "sb_bread() failed. Cannot "
530 "read attribute list.");
533 if (al + block_size >= al_end)
535 memcpy(al, bh->b_data, block_size);
538 } while (++block < max_block);
541 if (initialized_size < size) {
543 memset(al_start + initialized_size, 0, size - initialized_size);
546 up_read(&runlist->lock);
553 * Note: The attribute list can be smaller than its allocation
554 * by multiple clusters. This has been encountered by at least
555 * two people running Windows XP, thus we cannot do any
556 * truncation sanity checking here. (AIA)
558 memcpy(al, bh->b_data, al_end - al);
560 if (initialized_size < size)
566 ntfs_error(sb, "Attribute list buffer overflow. Read attribute list "
574 * ntfs_external_attr_find - find an attribute in the attribute list of an inode
575 * @type: attribute type to find
576 * @name: attribute name to find (optional, i.e. NULL means don't care)
577 * @name_len: attribute name length (only needed if @name present)
578 * @ic: IGNORE_CASE or CASE_SENSITIVE (ignored if @name not present)
579 * @lowest_vcn: lowest vcn to find (optional, non-resident attributes only)
580 * @val: attribute value to find (optional, resident attributes only)
581 * @val_len: attribute value length
582 * @ctx: search context with mft record and attribute to search from
584 * You should not need to call this function directly. Use ntfs_attr_lookup()
587 * Find an attribute by searching the attribute list for the corresponding
588 * attribute list entry. Having found the entry, map the mft record if the
589 * attribute is in a different mft record/inode, ntfs_attr_find() the attribute
590 * in there and return it.
592 * On first search @ctx->ntfs_ino must be the base mft record and @ctx must
593 * have been obtained from a call to ntfs_attr_get_search_ctx(). On subsequent
594 * calls @ctx->ntfs_ino can be any extent inode, too (@ctx->base_ntfs_ino is
595 * then the base inode).
597 * After finishing with the attribute/mft record you need to call
598 * ntfs_attr_put_search_ctx() to cleanup the search context (unmapping any
599 * mapped inodes, etc).
601 * If the attribute is found, ntfs_external_attr_find() returns 0 and
602 * @ctx->attr will point to the found attribute. @ctx->mrec will point to the
603 * mft record in which @ctx->attr is located and @ctx->al_entry will point to
604 * the attribute list entry for the attribute.
606 * If the attribute is not found, ntfs_external_attr_find() returns -ENOENT and
607 * @ctx->attr will point to the attribute in the base mft record before which
608 * the attribute being searched for would need to be inserted if such an action
609 * were to be desired. @ctx->mrec will point to the mft record in which
610 * @ctx->attr is located and @ctx->al_entry will point to the attribute list
611 * entry of the attribute before which the attribute being searched for would
612 * need to be inserted if such an action were to be desired.
614 * Thus to insert the not found attribute, one wants to add the attribute to
615 * @ctx->mrec (the base mft record) and if there is not enough space, the
616 * attribute should be placed in a newly allocated extent mft record. The
617 * attribute list entry for the inserted attribute should be inserted in the
618 * attribute list attribute at @ctx->al_entry.
620 * On actual error, ntfs_external_attr_find() returns -EIO. In this case
621 * @ctx->attr is undefined and in particular do not rely on it not changing.
623 static int ntfs_external_attr_find(const ATTR_TYPE type,
624 const ntfschar *name, const u32 name_len,
625 const IGNORE_CASE_BOOL ic, const VCN lowest_vcn,
626 const u8 *val, const u32 val_len, ntfs_attr_search_ctx *ctx)
628 ntfs_inode *base_ni, *ni;
630 ATTR_LIST_ENTRY *al_entry, *next_al_entry;
631 u8 *al_start, *al_end;
636 static const char *es = " Unmount and run chkdsk.";
639 base_ni = ctx->base_ntfs_ino;
640 ntfs_debug("Entering for inode 0x%lx, type 0x%x.", ni->mft_no, type);
642 /* First call happens with the base mft record. */
643 base_ni = ctx->base_ntfs_ino = ctx->ntfs_ino;
644 ctx->base_mrec = ctx->mrec;
647 ctx->base_attr = ctx->attr;
651 al_start = base_ni->attr_list;
652 al_end = al_start + base_ni->attr_list_size;
654 ctx->al_entry = (ATTR_LIST_ENTRY*)al_start;
656 * Iterate over entries in attribute list starting at @ctx->al_entry,
657 * or the entry following that, if @ctx->is_first is TRUE.
660 al_entry = ctx->al_entry;
661 ctx->is_first = FALSE;
663 al_entry = (ATTR_LIST_ENTRY*)((u8*)ctx->al_entry +
664 le16_to_cpu(ctx->al_entry->length));
665 for (;; al_entry = next_al_entry) {
666 /* Out of bounds check. */
667 if ((u8*)al_entry < base_ni->attr_list ||
668 (u8*)al_entry > al_end)
669 break; /* Inode is corrupt. */
670 ctx->al_entry = al_entry;
671 /* Catch the end of the attribute list. */
672 if ((u8*)al_entry == al_end)
674 if (!al_entry->length)
676 if ((u8*)al_entry + 6 > al_end || (u8*)al_entry +
677 le16_to_cpu(al_entry->length) > al_end)
679 next_al_entry = (ATTR_LIST_ENTRY*)((u8*)al_entry +
680 le16_to_cpu(al_entry->length));
681 if (le32_to_cpu(al_entry->type) > le32_to_cpu(type))
683 if (type != al_entry->type)
686 * If @name is present, compare the two names. If @name is
687 * missing, assume we want an unnamed attribute.
689 al_name_len = al_entry->name_length;
690 al_name = (ntfschar*)((u8*)al_entry + al_entry->name_offset);
694 } else if (!ntfs_are_names_equal(al_name, al_name_len, name,
695 name_len, ic, vol->upcase, vol->upcase_len)) {
698 rc = ntfs_collate_names(name, name_len, al_name,
699 al_name_len, 1, IGNORE_CASE,
700 vol->upcase, vol->upcase_len);
702 * If @name collates before al_name, there is no
703 * matching attribute.
707 /* If the strings are not equal, continue search. */
711 * FIXME: Reverse engineering showed 0, IGNORE_CASE but
712 * that is inconsistent with ntfs_attr_find(). The
713 * subsequent rc checks were also different. Perhaps I
714 * made a mistake in one of the two. Need to recheck
715 * which is correct or at least see what is going on...
718 rc = ntfs_collate_names(name, name_len, al_name,
719 al_name_len, 1, CASE_SENSITIVE,
720 vol->upcase, vol->upcase_len);
727 * The names match or @name not present and attribute is
728 * unnamed. Now check @lowest_vcn. Continue search if the
729 * next attribute list entry still fits @lowest_vcn. Otherwise
730 * we have reached the right one or the search has failed.
732 if (lowest_vcn && (u8*)next_al_entry >= al_start &&
733 (u8*)next_al_entry + 6 < al_end &&
734 (u8*)next_al_entry + le16_to_cpu(
735 next_al_entry->length) <= al_end &&
736 sle64_to_cpu(next_al_entry->lowest_vcn) <=
738 next_al_entry->type == al_entry->type &&
739 next_al_entry->name_length == al_name_len &&
740 ntfs_are_names_equal((ntfschar*)((u8*)
742 next_al_entry->name_offset),
743 next_al_entry->name_length,
744 al_name, al_name_len, CASE_SENSITIVE,
745 vol->upcase, vol->upcase_len))
747 if (MREF_LE(al_entry->mft_reference) == ni->mft_no) {
748 if (MSEQNO_LE(al_entry->mft_reference) != ni->seq_no) {
749 ntfs_error(vol->sb, "Found stale mft "
750 "reference in attribute list "
751 "of base inode 0x%lx.%s",
752 base_ni->mft_no, es);
756 } else { /* Mft references do not match. */
757 /* If there is a mapped record unmap it first. */
759 unmap_extent_mft_record(ni);
760 /* Do we want the base record back? */
761 if (MREF_LE(al_entry->mft_reference) ==
763 ni = ctx->ntfs_ino = base_ni;
764 ctx->mrec = ctx->base_mrec;
766 /* We want an extent record. */
767 ctx->mrec = map_extent_mft_record(base_ni,
769 al_entry->mft_reference), &ni);
770 if (IS_ERR(ctx->mrec)) {
771 ntfs_error(vol->sb, "Failed to map "
773 "0x%lx of base inode "
777 base_ni->mft_no, es);
778 err = PTR_ERR(ctx->mrec);
781 /* Cause @ctx to be sanitized below. */
787 ctx->attr = (ATTR_RECORD*)((u8*)ctx->mrec +
788 le16_to_cpu(ctx->mrec->attrs_offset));
791 * ctx->vfs_ino, ctx->mrec, and ctx->attr now point to the
792 * mft record containing the attribute represented by the
796 * We could call into ntfs_attr_find() to find the right
797 * attribute in this mft record but this would be less
798 * efficient and not quite accurate as ntfs_attr_find() ignores
799 * the attribute instance numbers for example which become
800 * important when one plays with attribute lists. Also,
801 * because a proper match has been found in the attribute list
802 * entry above, the comparison can now be optimized. So it is
803 * worth re-implementing a simplified ntfs_attr_find() here.
807 * Use a manual loop so we can still use break and continue
808 * with the same meanings as above.
811 if ((u8*)a < (u8*)ctx->mrec || (u8*)a > (u8*)ctx->mrec +
812 le32_to_cpu(ctx->mrec->bytes_allocated))
814 if (a->type == AT_END)
818 if (al_entry->instance != a->instance)
821 * If the type and/or the name are mismatched between the
822 * attribute list entry and the attribute record, there is
823 * corruption so we break and return error EIO.
825 if (al_entry->type != a->type)
827 if (!ntfs_are_names_equal((ntfschar*)((u8*)a +
828 le16_to_cpu(a->name_offset)), a->name_length,
829 al_name, al_name_len, CASE_SENSITIVE,
830 vol->upcase, vol->upcase_len))
834 * If no @val specified or @val specified and it matches, we
837 if (!val || (!a->non_resident && le32_to_cpu(
838 a->data.resident.value_length) == val_len &&
840 le16_to_cpu(a->data.resident.value_offset),
842 ntfs_debug("Done, found.");
846 /* Proceed to the next attribute in the current mft record. */
847 a = (ATTR_RECORD*)((u8*)a + le32_to_cpu(a->length));
848 goto do_next_attr_loop;
851 ntfs_error(vol->sb, "Base inode 0x%lx contains corrupt "
852 "attribute list attribute.%s", base_ni->mft_no,
858 unmap_extent_mft_record(ni);
859 ctx->ntfs_ino = base_ni;
860 ctx->mrec = ctx->base_mrec;
861 ctx->attr = ctx->base_attr;
868 * If we were looking for AT_END, we reset the search context @ctx and
869 * use ntfs_attr_find() to seek to the end of the base mft record.
871 if (type == AT_END) {
872 ntfs_attr_reinit_search_ctx(ctx);
873 return ntfs_attr_find(AT_END, name, name_len, ic, val, val_len,
877 * The attribute was not found. Before we return, we want to ensure
878 * @ctx->mrec and @ctx->attr indicate the position at which the
879 * attribute should be inserted in the base mft record. Since we also
880 * want to preserve @ctx->al_entry we cannot reinitialize the search
881 * context using ntfs_attr_reinit_search_ctx() as this would set
882 * @ctx->al_entry to NULL. Thus we do the necessary bits manually (see
883 * ntfs_attr_init_search_ctx() below). Note, we _only_ preserve
884 * @ctx->al_entry as the remaining fields (base_*) are identical to
885 * their non base_ counterparts and we cannot set @ctx->base_attr
886 * correctly yet as we do not know what @ctx->attr will be set to by
887 * the call to ntfs_attr_find() below.
890 unmap_extent_mft_record(ni);
891 ctx->mrec = ctx->base_mrec;
892 ctx->attr = (ATTR_RECORD*)((u8*)ctx->mrec +
893 le16_to_cpu(ctx->mrec->attrs_offset));
894 ctx->is_first = TRUE;
895 ctx->ntfs_ino = base_ni;
896 ctx->base_ntfs_ino = NULL;
897 ctx->base_mrec = NULL;
898 ctx->base_attr = NULL;
900 * In case there are multiple matches in the base mft record, need to
901 * keep enumerating until we get an attribute not found response (or
902 * another error), otherwise we would keep returning the same attribute
903 * over and over again and all programs using us for enumeration would
904 * lock up in a tight loop.
907 err = ntfs_attr_find(type, name, name_len, ic, val, val_len,
910 ntfs_debug("Done, not found.");
915 * ntfs_attr_lookup - find an attribute in an ntfs inode
916 * @type: attribute type to find
917 * @name: attribute name to find (optional, i.e. NULL means don't care)
918 * @name_len: attribute name length (only needed if @name present)
919 * @ic: IGNORE_CASE or CASE_SENSITIVE (ignored if @name not present)
920 * @lowest_vcn: lowest vcn to find (optional, non-resident attributes only)
921 * @val: attribute value to find (optional, resident attributes only)
922 * @val_len: attribute value length
923 * @ctx: search context with mft record and attribute to search from
925 * Find an attribute in an ntfs inode. On first search @ctx->ntfs_ino must
926 * be the base mft record and @ctx must have been obtained from a call to
927 * ntfs_attr_get_search_ctx().
929 * This function transparently handles attribute lists and @ctx is used to
930 * continue searches where they were left off at.
932 * After finishing with the attribute/mft record you need to call
933 * ntfs_attr_put_search_ctx() to cleanup the search context (unmapping any
934 * mapped inodes, etc).
936 * Return 0 if the search was successful and -errno if not.
938 * When 0, @ctx->attr is the found attribute and it is in mft record
939 * @ctx->mrec. If an attribute list attribute is present, @ctx->al_entry is
940 * the attribute list entry of the found attribute.
942 * When -ENOENT, @ctx->attr is the attribute which collates just after the
943 * attribute being searched for, i.e. if one wants to add the attribute to the
944 * mft record this is the correct place to insert it into. If an attribute
945 * list attribute is present, @ctx->al_entry is the attribute list entry which
946 * collates just after the attribute list entry of the attribute being searched
947 * for, i.e. if one wants to add the attribute to the mft record this is the
948 * correct place to insert its attribute list entry into.
950 * When -errno != -ENOENT, an error occured during the lookup. @ctx->attr is
951 * then undefined and in particular you should not rely on it not changing.
953 int ntfs_attr_lookup(const ATTR_TYPE type, const ntfschar *name,
954 const u32 name_len, const IGNORE_CASE_BOOL ic,
955 const VCN lowest_vcn, const u8 *val, const u32 val_len,
956 ntfs_attr_search_ctx *ctx)
960 ntfs_debug("Entering.");
961 if (ctx->base_ntfs_ino)
962 base_ni = ctx->base_ntfs_ino;
964 base_ni = ctx->ntfs_ino;
965 /* Sanity check, just for debugging really. */
967 if (!NInoAttrList(base_ni) || type == AT_ATTRIBUTE_LIST)
968 return ntfs_attr_find(type, name, name_len, ic, val, val_len,
970 return ntfs_external_attr_find(type, name, name_len, ic, lowest_vcn,
975 * ntfs_attr_init_search_ctx - initialize an attribute search context
976 * @ctx: attribute search context to initialize
977 * @ni: ntfs inode with which to initialize the search context
978 * @mrec: mft record with which to initialize the search context
980 * Initialize the attribute search context @ctx with @ni and @mrec.
982 static inline void ntfs_attr_init_search_ctx(ntfs_attr_search_ctx *ctx,
983 ntfs_inode *ni, MFT_RECORD *mrec)
986 /* Sanity checks are performed elsewhere. */
987 ctx->attr = (ATTR_RECORD*)((u8*)mrec + le16_to_cpu(mrec->attrs_offset));
988 ctx->is_first = TRUE;
990 ctx->al_entry = NULL;
991 ctx->base_ntfs_ino = NULL;
992 ctx->base_mrec = NULL;
993 ctx->base_attr = NULL;
997 * ntfs_attr_reinit_search_ctx - reinitialize an attribute search context
998 * @ctx: attribute search context to reinitialize
1000 * Reinitialize the attribute search context @ctx, unmapping an associated
1001 * extent mft record if present, and initialize the search context again.
1003 * This is used when a search for a new attribute is being started to reset
1004 * the search context to the beginning.
1006 void ntfs_attr_reinit_search_ctx(ntfs_attr_search_ctx *ctx)
1008 if (likely(!ctx->base_ntfs_ino)) {
1009 /* No attribute list. */
1010 ctx->is_first = TRUE;
1011 /* Sanity checks are performed elsewhere. */
1012 ctx->attr = (ATTR_RECORD*)((u8*)ctx->mrec +
1013 le16_to_cpu(ctx->mrec->attrs_offset));
1015 * This needs resetting due to ntfs_external_attr_find() which
1016 * can leave it set despite having zeroed ctx->base_ntfs_ino.
1018 ctx->al_entry = NULL;
1020 } /* Attribute list. */
1021 if (ctx->ntfs_ino != ctx->base_ntfs_ino)
1022 unmap_extent_mft_record(ctx->ntfs_ino);
1023 ntfs_attr_init_search_ctx(ctx, ctx->base_ntfs_ino, ctx->base_mrec);
1028 * ntfs_attr_get_search_ctx - allocate/initialize a new attribute search context
1029 * @ni: ntfs inode with which to initialize the search context
1030 * @mrec: mft record with which to initialize the search context
1032 * Allocate a new attribute search context, initialize it with @ni and @mrec,
1033 * and return it. Return NULL if allocation failed.
1035 ntfs_attr_search_ctx *ntfs_attr_get_search_ctx(ntfs_inode *ni, MFT_RECORD *mrec)
1037 ntfs_attr_search_ctx *ctx;
1039 ctx = kmem_cache_alloc(ntfs_attr_ctx_cache, SLAB_NOFS);
1041 ntfs_attr_init_search_ctx(ctx, ni, mrec);
1046 * ntfs_attr_put_search_ctx - release an attribute search context
1047 * @ctx: attribute search context to free
1049 * Release the attribute search context @ctx, unmapping an associated extent
1050 * mft record if present.
1052 void ntfs_attr_put_search_ctx(ntfs_attr_search_ctx *ctx)
1054 if (ctx->base_ntfs_ino && ctx->ntfs_ino != ctx->base_ntfs_ino)
1055 unmap_extent_mft_record(ctx->ntfs_ino);
1056 kmem_cache_free(ntfs_attr_ctx_cache, ctx);
1061 * ntfs_attr_find_in_attrdef - find an attribute in the $AttrDef system file
1062 * @vol: ntfs volume to which the attribute belongs
1063 * @type: attribute type which to find
1065 * Search for the attribute definition record corresponding to the attribute
1066 * @type in the $AttrDef system file.
1068 * Return the attribute type definition record if found and NULL if not found.
1070 static ATTR_DEF *ntfs_attr_find_in_attrdef(const ntfs_volume *vol,
1071 const ATTR_TYPE type)
1075 BUG_ON(!vol->attrdef);
1077 for (ad = vol->attrdef; (u8*)ad - (u8*)vol->attrdef <
1078 vol->attrdef_size && ad->type; ++ad) {
1079 /* We have not found it yet, carry on searching. */
1080 if (likely(le32_to_cpu(ad->type) < le32_to_cpu(type)))
1082 /* We found the attribute; return it. */
1083 if (likely(ad->type == type))
1085 /* We have gone too far already. No point in continuing. */
1088 /* Attribute not found. */
1089 ntfs_debug("Attribute type 0x%x not found in $AttrDef.",
1095 * ntfs_attr_size_bounds_check - check a size of an attribute type for validity
1096 * @vol: ntfs volume to which the attribute belongs
1097 * @type: attribute type which to check
1098 * @size: size which to check
1100 * Check whether the @size in bytes is valid for an attribute of @type on the
1101 * ntfs volume @vol. This information is obtained from $AttrDef system file.
1103 * Return 0 if valid, -ERANGE if not valid, or -ENOENT if the attribute is not
1104 * listed in $AttrDef.
1106 int ntfs_attr_size_bounds_check(const ntfs_volume *vol, const ATTR_TYPE type,
1113 * $ATTRIBUTE_LIST has a maximum size of 256kiB, but this is not
1114 * listed in $AttrDef.
1116 if (unlikely(type == AT_ATTRIBUTE_LIST && size > 256 * 1024))
1118 /* Get the $AttrDef entry for the attribute @type. */
1119 ad = ntfs_attr_find_in_attrdef(vol, type);
1122 /* Do the bounds check. */
1123 if (((sle64_to_cpu(ad->min_size) > 0) &&
1124 size < sle64_to_cpu(ad->min_size)) ||
1125 ((sle64_to_cpu(ad->max_size) > 0) && size >
1126 sle64_to_cpu(ad->max_size)))
1132 * ntfs_attr_can_be_non_resident - check if an attribute can be non-resident
1133 * @vol: ntfs volume to which the attribute belongs
1134 * @type: attribute type which to check
1136 * Check whether the attribute of @type on the ntfs volume @vol is allowed to
1137 * be non-resident. This information is obtained from $AttrDef system file.
1139 * Return 0 if the attribute is allowed to be non-resident, -EPERM if not, or
1140 * -ENOENT if the attribute is not listed in $AttrDef.
1142 int ntfs_attr_can_be_non_resident(const ntfs_volume *vol, const ATTR_TYPE type)
1147 * $DATA and $EA are always allowed to be non-resident even if $AttrDef
1148 * does not specify this in the flags of the $DATA attribute definition
1151 if (type == AT_DATA || type == AT_EA)
1153 /* Find the attribute definition record in $AttrDef. */
1154 ad = ntfs_attr_find_in_attrdef(vol, type);
1157 /* Check the flags and return the result. */
1158 if (ad->flags & CAN_BE_NON_RESIDENT)
1164 * ntfs_attr_can_be_resident - check if an attribute can be resident
1165 * @vol: ntfs volume to which the attribute belongs
1166 * @type: attribute type which to check
1168 * Check whether the attribute of @type on the ntfs volume @vol is allowed to
1169 * be resident. This information is derived from our ntfs knowledge and may
1170 * not be completely accurate, especially when user defined attributes are
1171 * present. Basically we allow everything to be resident except for index
1172 * allocation and $EA attributes.
1174 * Return 0 if the attribute is allowed to be non-resident and -EPERM if not.
1176 * Warning: In the system file $MFT the attribute $Bitmap must be non-resident
1177 * otherwise windows will not boot (blue screen of death)! We cannot
1178 * check for this here as we do not know which inode's $Bitmap is
1179 * being asked about so the caller needs to special case this.
1181 int ntfs_attr_can_be_resident(const ntfs_volume *vol, const ATTR_TYPE type)
1183 if (type != AT_INDEX_ALLOCATION && type != AT_EA)
1189 * ntfs_attr_record_resize - resize an attribute record
1190 * @m: mft record containing attribute record
1191 * @a: attribute record to resize
1192 * @new_size: new size in bytes to which to resize the attribute record @a
1194 * Resize the attribute record @a, i.e. the resident part of the attribute, in
1195 * the mft record @m to @new_size bytes.
1197 * Return 0 on success and -errno on error. The following error codes are
1199 * -ENOSPC - Not enough space in the mft record @m to perform the resize.
1201 * Note: On error, no modifications have been performed whatsoever.
1203 * Warning: If you make a record smaller without having copied all the data you
1204 * are interested in the data may be overwritten.
1206 int ntfs_attr_record_resize(MFT_RECORD *m, ATTR_RECORD *a, u32 new_size)
1208 ntfs_debug("Entering for new_size %u.", new_size);
1209 /* Align to 8 bytes if it is not already done. */
1211 new_size = (new_size + 7) & ~7;
1212 /* If the actual attribute length has changed, move things around. */
1213 if (new_size != le32_to_cpu(a->length)) {
1214 u32 new_muse = le32_to_cpu(m->bytes_in_use) -
1215 le32_to_cpu(a->length) + new_size;
1216 /* Not enough space in this mft record. */
1217 if (new_muse > le32_to_cpu(m->bytes_allocated))
1219 /* Move attributes following @a to their new location. */
1220 memmove((u8*)a + new_size, (u8*)a + le32_to_cpu(a->length),
1221 le32_to_cpu(m->bytes_in_use) - ((u8*)a -
1222 (u8*)m) - le32_to_cpu(a->length));
1223 /* Adjust @m to reflect the change in used space. */
1224 m->bytes_in_use = cpu_to_le32(new_muse);
1225 /* Adjust @a to reflect the new size. */
1226 if (new_size >= offsetof(ATTR_REC, length) + sizeof(a->length))
1227 a->length = cpu_to_le32(new_size);
1233 * ntfs_attr_make_non_resident - convert a resident to a non-resident attribute
1234 * @ni: ntfs inode describing the attribute to convert
1236 * Convert the resident ntfs attribute described by the ntfs inode @ni to a
1239 * Return 0 on success and -errno on error. The following error return codes
1241 * -EPERM - The attribute is not allowed to be non-resident.
1242 * -ENOMEM - Not enough memory.
1243 * -ENOSPC - Not enough disk space.
1244 * -EINVAL - Attribute not defined on the volume.
1245 * -EIO - I/o error or other error.
1247 * NOTE to self: No changes in the attribute list are required to move from
1248 * a resident to a non-resident attribute.
1250 * Locking: - The caller must hold i_sem on the inode.
1252 int ntfs_attr_make_non_resident(ntfs_inode *ni)
1255 struct inode *vi = VFS_I(ni);
1256 ntfs_volume *vol = ni->vol;
1257 ntfs_inode *base_ni;
1260 ntfs_attr_search_ctx *ctx;
1262 runlist_element *rl;
1264 unsigned long flags;
1265 int mp_size, mp_ofs, name_ofs, arec_size, err, err2;
1267 u8 old_res_attr_flags;
1269 /* Check that the attribute is allowed to be non-resident. */
1270 err = ntfs_attr_can_be_non_resident(vol, ni->type);
1271 if (unlikely(err)) {
1273 ntfs_debug("Attribute is not allowed to be "
1276 ntfs_debug("Attribute not defined on the NTFS "
1281 * The size needs to be aligned to a cluster boundary for allocation
1284 new_size = (i_size_read(vi) + vol->cluster_size - 1) &
1285 ~(vol->cluster_size - 1);
1288 * Will need the page later and since the page lock nests
1289 * outside all ntfs locks, we need to get the page now.
1291 page = find_or_create_page(vi->i_mapping, 0,
1292 mapping_gfp_mask(vi->i_mapping));
1293 if (unlikely(!page))
1295 /* Start by allocating clusters to hold the attribute value. */
1296 rl = ntfs_cluster_alloc(vol, 0, new_size >>
1297 vol->cluster_size_bits, -1, DATA_ZONE);
1300 ntfs_debug("Failed to allocate cluster%s, error code "
1301 "%i.\n", (new_size >>
1302 vol->cluster_size_bits) > 1 ? "s" : "",
1310 /* Determine the size of the mapping pairs array. */
1311 mp_size = ntfs_get_size_for_mapping_pairs(vol, rl, 0);
1312 if (unlikely(mp_size < 0)) {
1314 ntfs_debug("Failed to get size for mapping pairs array, error "
1318 down_write(&ni->runlist.lock);
1322 base_ni = ni->ext.base_ntfs_ino;
1323 m = map_mft_record(base_ni);
1330 ctx = ntfs_attr_get_search_ctx(base_ni, m);
1331 if (unlikely(!ctx)) {
1335 err = ntfs_attr_lookup(ni->type, ni->name, ni->name_len,
1336 CASE_SENSITIVE, 0, NULL, 0, ctx);
1337 if (unlikely(err)) {
1344 BUG_ON(NInoNonResident(ni));
1345 BUG_ON(a->non_resident);
1347 * Calculate new offsets for the name and the mapping pairs array.
1348 * We assume the attribute is not compressed or sparse.
1350 name_ofs = (offsetof(ATTR_REC,
1351 data.non_resident.compressed_size) + 7) & ~7;
1352 mp_ofs = (name_ofs + a->name_length * sizeof(ntfschar) + 7) & ~7;
1354 * Determine the size of the resident part of the now non-resident
1357 arec_size = (mp_ofs + mp_size + 7) & ~7;
1359 * If the page is not uptodate bring it uptodate by copying from the
1362 attr_size = le32_to_cpu(a->data.resident.value_length);
1363 BUG_ON(attr_size != i_size_read(vi));
1364 if (page && !PageUptodate(page)) {
1365 kaddr = kmap_atomic(page, KM_USER0);
1366 memcpy(kaddr, (u8*)a +
1367 le16_to_cpu(a->data.resident.value_offset),
1369 memset(kaddr + attr_size, 0, PAGE_CACHE_SIZE - attr_size);
1370 kunmap_atomic(kaddr, KM_USER0);
1371 flush_dcache_page(page);
1372 SetPageUptodate(page);
1374 /* Backup the attribute flag. */
1375 old_res_attr_flags = a->data.resident.flags;
1376 /* Resize the resident part of the attribute record. */
1377 err = ntfs_attr_record_resize(m, a, arec_size);
1381 * Convert the resident part of the attribute record to describe a
1382 * non-resident attribute.
1384 a->non_resident = 1;
1385 /* Move the attribute name if it exists and update the offset. */
1387 memmove((u8*)a + name_ofs, (u8*)a + le16_to_cpu(a->name_offset),
1388 a->name_length * sizeof(ntfschar));
1389 a->name_offset = cpu_to_le16(name_ofs);
1391 * FIXME: For now just clear all of these as we do not support them
1394 a->flags &= cpu_to_le16(0xffff & ~le16_to_cpu(ATTR_IS_SPARSE |
1395 ATTR_IS_ENCRYPTED | ATTR_COMPRESSION_MASK));
1396 /* Setup the fields specific to non-resident attributes. */
1397 a->data.non_resident.lowest_vcn = 0;
1398 a->data.non_resident.highest_vcn = cpu_to_sle64((new_size - 1) >>
1399 vol->cluster_size_bits);
1400 a->data.non_resident.mapping_pairs_offset = cpu_to_le16(mp_ofs);
1401 a->data.non_resident.compression_unit = 0;
1402 memset(&a->data.non_resident.reserved, 0,
1403 sizeof(a->data.non_resident.reserved));
1404 a->data.non_resident.allocated_size = cpu_to_sle64(new_size);
1405 a->data.non_resident.data_size =
1406 a->data.non_resident.initialized_size =
1407 cpu_to_sle64(attr_size);
1408 /* Generate the mapping pairs array into the attribute record. */
1409 err = ntfs_mapping_pairs_build(vol, (u8*)a + mp_ofs,
1410 arec_size - mp_ofs, rl, 0, NULL);
1411 if (unlikely(err)) {
1412 ntfs_debug("Failed to build mapping pairs, error code %i.",
1416 /* Setup the in-memory attribute structure to be non-resident. */
1418 * FIXME: For now just clear all of these as we do not support them
1421 NInoClearSparse(ni);
1422 NInoClearEncrypted(ni);
1423 NInoClearCompressed(ni);
1424 ni->runlist.rl = rl;
1425 write_lock_irqsave(&ni->size_lock, flags);
1426 ni->allocated_size = new_size;
1427 write_unlock_irqrestore(&ni->size_lock, flags);
1429 * This needs to be last since the address space operations ->readpage
1430 * and ->writepage can run concurrently with us as they are not
1431 * serialized on i_sem. Note, we are not allowed to fail once we flip
1432 * this switch, which is another reason to do this last.
1434 NInoSetNonResident(ni);
1435 /* Mark the mft record dirty, so it gets written back. */
1436 flush_dcache_mft_record_page(ctx->ntfs_ino);
1437 mark_mft_record_dirty(ctx->ntfs_ino);
1438 ntfs_attr_put_search_ctx(ctx);
1439 unmap_mft_record(base_ni);
1440 up_write(&ni->runlist.lock);
1442 set_page_dirty(page);
1444 mark_page_accessed(page);
1445 page_cache_release(page);
1447 ntfs_debug("Done.");
1450 /* Convert the attribute back into a resident attribute. */
1451 a->non_resident = 0;
1452 /* Move the attribute name if it exists and update the offset. */
1453 name_ofs = (offsetof(ATTR_RECORD, data.resident.reserved) +
1454 sizeof(a->data.resident.reserved) + 7) & ~7;
1456 memmove((u8*)a + name_ofs, (u8*)a + le16_to_cpu(a->name_offset),
1457 a->name_length * sizeof(ntfschar));
1458 mp_ofs = (name_ofs + a->name_length * sizeof(ntfschar) + 7) & ~7;
1459 a->name_offset = cpu_to_le16(name_ofs);
1460 arec_size = (mp_ofs + attr_size + 7) & ~7;
1461 /* Resize the resident part of the attribute record. */
1462 err2 = ntfs_attr_record_resize(m, a, arec_size);
1463 if (unlikely(err2)) {
1465 * This cannot happen (well if memory corruption is at work it
1466 * could happen in theory), but deal with it as well as we can.
1467 * If the old size is too small, truncate the attribute,
1468 * otherwise simply give it a larger allocated size.
1469 * FIXME: Should check whether chkdsk complains when the
1470 * allocated size is much bigger than the resident value size.
1472 arec_size = le32_to_cpu(a->length);
1473 if ((mp_ofs + attr_size) > arec_size) {
1475 attr_size = arec_size - mp_ofs;
1476 ntfs_error(vol->sb, "Failed to undo partial resident "
1477 "to non-resident attribute "
1478 "conversion. Truncating inode 0x%lx, "
1479 "attribute type 0x%x from %i bytes to "
1480 "%i bytes to maintain metadata "
1481 "consistency. THIS MEANS YOU ARE "
1482 "LOSING %i BYTES DATA FROM THIS %s.",
1484 (unsigned)le32_to_cpu(ni->type),
1485 err2, attr_size, err2 - attr_size,
1486 ((ni->type == AT_DATA) &&
1487 !ni->name_len) ? "FILE": "ATTRIBUTE");
1488 write_lock_irqsave(&ni->size_lock, flags);
1489 ni->initialized_size = attr_size;
1490 i_size_write(vi, attr_size);
1491 write_unlock_irqrestore(&ni->size_lock, flags);
1494 /* Setup the fields specific to resident attributes. */
1495 a->data.resident.value_length = cpu_to_le32(attr_size);
1496 a->data.resident.value_offset = cpu_to_le16(mp_ofs);
1497 a->data.resident.flags = old_res_attr_flags;
1498 memset(&a->data.resident.reserved, 0,
1499 sizeof(a->data.resident.reserved));
1500 /* Copy the data from the page back to the attribute value. */
1502 kaddr = kmap_atomic(page, KM_USER0);
1503 memcpy((u8*)a + mp_ofs, kaddr, attr_size);
1504 kunmap_atomic(kaddr, KM_USER0);
1506 /* Setup the allocated size in the ntfs inode in case it changed. */
1507 write_lock_irqsave(&ni->size_lock, flags);
1508 ni->allocated_size = arec_size - mp_ofs;
1509 write_unlock_irqrestore(&ni->size_lock, flags);
1510 /* Mark the mft record dirty, so it gets written back. */
1511 flush_dcache_mft_record_page(ctx->ntfs_ino);
1512 mark_mft_record_dirty(ctx->ntfs_ino);
1515 ntfs_attr_put_search_ctx(ctx);
1517 unmap_mft_record(base_ni);
1518 ni->runlist.rl = NULL;
1519 up_write(&ni->runlist.lock);
1522 if (ntfs_cluster_free_from_rl(vol, rl) < 0) {
1524 ntfs_error(vol->sb, "Failed to release allocated "
1525 "cluster(s) in error code path. Run "
1526 "chkdsk to recover the lost "
1532 page_cache_release(page);
1540 * ntfs_attr_set - fill (a part of) an attribute with a byte
1541 * @ni: ntfs inode describing the attribute to fill
1542 * @ofs: offset inside the attribute at which to start to fill
1543 * @cnt: number of bytes to fill
1544 * @val: the unsigned 8-bit value with which to fill the attribute
1546 * Fill @cnt bytes of the attribute described by the ntfs inode @ni starting at
1547 * byte offset @ofs inside the attribute with the constant byte @val.
1549 * This function is effectively like memset() applied to an ntfs attribute.
1550 * Note thie function actually only operates on the page cache pages belonging
1551 * to the ntfs attribute and it marks them dirty after doing the memset().
1552 * Thus it relies on the vm dirty page write code paths to cause the modified
1553 * pages to be written to the mft record/disk.
1555 * Return 0 on success and -errno on error. An error code of -ESPIPE means
1556 * that @ofs + @cnt were outside the end of the attribute and no write was
1559 int ntfs_attr_set(ntfs_inode *ni, const s64 ofs, const s64 cnt, const u8 val)
1561 ntfs_volume *vol = ni->vol;
1562 struct address_space *mapping;
1566 unsigned int start_ofs, end_ofs, size;
1568 ntfs_debug("Entering for ofs 0x%llx, cnt 0x%llx, val 0x%hx.",
1569 (long long)ofs, (long long)cnt, val);
1574 mapping = VFS_I(ni)->i_mapping;
1575 /* Work out the starting index and page offset. */
1576 idx = ofs >> PAGE_CACHE_SHIFT;
1577 start_ofs = ofs & ~PAGE_CACHE_MASK;
1578 /* Work out the ending index and page offset. */
1580 end_ofs = end & ~PAGE_CACHE_MASK;
1581 /* If the end is outside the inode size return -ESPIPE. */
1582 if (unlikely(end > i_size_read(VFS_I(ni)))) {
1583 ntfs_error(vol->sb, "Request exceeds end of attribute.");
1586 end >>= PAGE_CACHE_SHIFT;
1587 /* If there is a first partial page, need to do it the slow way. */
1589 page = read_cache_page(mapping, idx,
1590 (filler_t*)mapping->a_ops->readpage, NULL);
1592 ntfs_error(vol->sb, "Failed to read first partial "
1593 "page (sync error, index 0x%lx).", idx);
1594 return PTR_ERR(page);
1596 wait_on_page_locked(page);
1597 if (unlikely(!PageUptodate(page))) {
1598 ntfs_error(vol->sb, "Failed to read first partial page "
1599 "(async error, index 0x%lx).", idx);
1600 page_cache_release(page);
1601 return PTR_ERR(page);
1604 * If the last page is the same as the first page, need to
1605 * limit the write to the end offset.
1607 size = PAGE_CACHE_SIZE;
1610 kaddr = kmap_atomic(page, KM_USER0);
1611 memset(kaddr + start_ofs, val, size - start_ofs);
1612 flush_dcache_page(page);
1613 kunmap_atomic(kaddr, KM_USER0);
1614 set_page_dirty(page);
1615 page_cache_release(page);
1620 /* Do the whole pages the fast way. */
1621 for (; idx < end; idx++) {
1622 /* Find or create the current page. (The page is locked.) */
1623 page = grab_cache_page(mapping, idx);
1624 if (unlikely(!page)) {
1625 ntfs_error(vol->sb, "Insufficient memory to grab "
1626 "page (index 0x%lx).", idx);
1629 kaddr = kmap_atomic(page, KM_USER0);
1630 memset(kaddr, val, PAGE_CACHE_SIZE);
1631 flush_dcache_page(page);
1632 kunmap_atomic(kaddr, KM_USER0);
1634 * If the page has buffers, mark them uptodate since buffer
1635 * state and not page state is definitive in 2.6 kernels.
1637 if (page_has_buffers(page)) {
1638 struct buffer_head *bh, *head;
1640 bh = head = page_buffers(page);
1642 set_buffer_uptodate(bh);
1643 } while ((bh = bh->b_this_page) != head);
1645 /* Now that buffers are uptodate, set the page uptodate, too. */
1646 SetPageUptodate(page);
1648 * Set the page and all its buffers dirty and mark the inode
1649 * dirty, too. The VM will write the page later on.
1651 set_page_dirty(page);
1652 /* Finally unlock and release the page. */
1654 page_cache_release(page);
1656 /* If there is a last partial page, need to do it the slow way. */
1658 page = read_cache_page(mapping, idx,
1659 (filler_t*)mapping->a_ops->readpage, NULL);
1661 ntfs_error(vol->sb, "Failed to read last partial page "
1662 "(sync error, index 0x%lx).", idx);
1663 return PTR_ERR(page);
1665 wait_on_page_locked(page);
1666 if (unlikely(!PageUptodate(page))) {
1667 ntfs_error(vol->sb, "Failed to read last partial page "
1668 "(async error, index 0x%lx).", idx);
1669 page_cache_release(page);
1670 return PTR_ERR(page);
1672 kaddr = kmap_atomic(page, KM_USER0);
1673 memset(kaddr, val, end_ofs);
1674 flush_dcache_page(page);
1675 kunmap_atomic(kaddr, KM_USER0);
1676 set_page_dirty(page);
1677 page_cache_release(page);
1680 ntfs_debug("Done.");