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>
35 * ntfs_map_runlist_nolock - map (a part of) a runlist of an ntfs inode
36 * @ni: ntfs inode for which to map (part of) a runlist
37 * @vcn: map runlist part containing this vcn
39 * Map the part of a runlist containing the @vcn of the ntfs inode @ni.
41 * Return 0 on success and -errno on error.
43 * Locking: - The runlist must be locked for writing.
44 * - This function modifies the runlist.
46 int ntfs_map_runlist_nolock(ntfs_inode *ni, VCN vcn)
50 ntfs_attr_search_ctx *ctx;
54 ntfs_debug("Mapping runlist part containing vcn 0x%llx.",
55 (unsigned long long)vcn);
59 base_ni = ni->ext.base_ntfs_ino;
60 mrec = map_mft_record(base_ni);
63 ctx = ntfs_attr_get_search_ctx(base_ni, mrec);
68 err = ntfs_attr_lookup(ni->type, ni->name, ni->name_len,
69 CASE_SENSITIVE, vcn, NULL, 0, ctx);
71 rl = ntfs_mapping_pairs_decompress(ni->vol, ctx->attr,
78 ntfs_attr_put_search_ctx(ctx);
80 unmap_mft_record(base_ni);
85 * ntfs_map_runlist - map (a part of) a runlist of an ntfs inode
86 * @ni: ntfs inode for which to map (part of) a runlist
87 * @vcn: map runlist part containing this vcn
89 * Map the part of a runlist containing the @vcn of the ntfs inode @ni.
91 * Return 0 on success and -errno on error.
93 * Locking: - The runlist must be unlocked on entry and is unlocked on return.
94 * - This function takes the runlist lock for writing and modifies the
97 int ntfs_map_runlist(ntfs_inode *ni, VCN vcn)
101 down_write(&ni->runlist.lock);
102 /* Make sure someone else didn't do the work while we were sleeping. */
103 if (likely(ntfs_rl_vcn_to_lcn(ni->runlist.rl, vcn) <=
105 err = ntfs_map_runlist_nolock(ni, vcn);
106 up_write(&ni->runlist.lock);
111 * ntfs_attr_vcn_to_lcn_nolock - convert a vcn into a lcn given an ntfs inode
112 * @ni: ntfs inode of the attribute whose runlist to search
113 * @vcn: vcn to convert
114 * @write_locked: true if the runlist is locked for writing
116 * Find the virtual cluster number @vcn in the runlist of the ntfs attribute
117 * described by the ntfs inode @ni and return the corresponding logical cluster
120 * If the @vcn is not mapped yet, the attempt is made to map the attribute
121 * extent containing the @vcn and the vcn to lcn conversion is retried.
123 * If @write_locked is true the caller has locked the runlist for writing and
124 * if false for reading.
126 * Since lcns must be >= 0, we use negative return codes with special meaning:
128 * Return code Meaning / Description
129 * ==========================================
130 * LCN_HOLE Hole / not allocated on disk.
131 * LCN_ENOENT There is no such vcn in the runlist, i.e. @vcn is out of bounds.
132 * LCN_ENOMEM Not enough memory to map runlist.
133 * LCN_EIO Critical error (runlist/file is corrupt, i/o error, etc).
135 * Locking: - The runlist must be locked on entry and is left locked on return.
136 * - If @write_locked is FALSE, i.e. the runlist is locked for reading,
137 * the lock may be dropped inside the function so you cannot rely on
138 * the runlist still being the same when this function returns.
140 LCN ntfs_attr_vcn_to_lcn_nolock(ntfs_inode *ni, const VCN vcn,
141 const BOOL write_locked)
144 BOOL is_retry = FALSE;
146 ntfs_debug("Entering for i_ino 0x%lx, vcn 0x%llx, %s_locked.",
147 ni->mft_no, (unsigned long long)vcn,
148 write_locked ? "write" : "read");
150 BUG_ON(!NInoNonResident(ni));
153 /* Convert vcn to lcn. If that fails map the runlist and retry once. */
154 lcn = ntfs_rl_vcn_to_lcn(ni->runlist.rl, vcn);
155 if (likely(lcn >= LCN_HOLE)) {
156 ntfs_debug("Done, lcn 0x%llx.", (long long)lcn);
159 if (lcn != LCN_RL_NOT_MAPPED) {
160 if (lcn != LCN_ENOENT)
162 } else if (!is_retry) {
166 up_read(&ni->runlist.lock);
167 down_write(&ni->runlist.lock);
168 if (unlikely(ntfs_rl_vcn_to_lcn(ni->runlist.rl, vcn) !=
169 LCN_RL_NOT_MAPPED)) {
170 up_write(&ni->runlist.lock);
171 down_read(&ni->runlist.lock);
175 err = ntfs_map_runlist_nolock(ni, vcn);
177 up_write(&ni->runlist.lock);
178 down_read(&ni->runlist.lock);
186 else if (err == -ENOMEM)
191 if (lcn != LCN_ENOENT)
192 ntfs_error(ni->vol->sb, "Failed with error code %lli.",
198 * ntfs_attr_find_vcn_nolock - find a vcn in the runlist of an ntfs inode
199 * @ni: ntfs inode describing the runlist to search
201 * @write_locked: true if the runlist is locked for writing
203 * Find the virtual cluster number @vcn in the runlist described by the ntfs
204 * inode @ni and return the address of the runlist element containing the @vcn.
206 * If the @vcn is not mapped yet, the attempt is made to map the attribute
207 * extent containing the @vcn and the vcn to lcn conversion is retried.
209 * If @write_locked is true the caller has locked the runlist for writing and
210 * if false for reading.
212 * Note you need to distinguish between the lcn of the returned runlist element
213 * being >= 0 and LCN_HOLE. In the later case you have to return zeroes on
214 * read and allocate clusters on write.
216 * Return the runlist element containing the @vcn on success and
217 * ERR_PTR(-errno) on error. You need to test the return value with IS_ERR()
218 * to decide if the return is success or failure and PTR_ERR() to get to the
219 * error code if IS_ERR() is true.
221 * The possible error return codes are:
222 * -ENOENT - No such vcn in the runlist, i.e. @vcn is out of bounds.
223 * -ENOMEM - Not enough memory to map runlist.
224 * -EIO - Critical error (runlist/file is corrupt, i/o error, etc).
226 * Locking: - The runlist must be locked on entry and is left locked on return.
227 * - If @write_locked is FALSE, i.e. the runlist is locked for reading,
228 * the lock may be dropped inside the function so you cannot rely on
229 * the runlist still being the same when this function returns.
231 runlist_element *ntfs_attr_find_vcn_nolock(ntfs_inode *ni, const VCN vcn,
232 const BOOL write_locked)
236 BOOL is_retry = FALSE;
238 ntfs_debug("Entering for i_ino 0x%lx, vcn 0x%llx, %s_locked.",
239 ni->mft_no, (unsigned long long)vcn,
240 write_locked ? "write" : "read");
242 BUG_ON(!NInoNonResident(ni));
246 if (likely(rl && vcn >= rl[0].vcn)) {
247 while (likely(rl->length)) {
248 if (unlikely(vcn < rl[1].vcn)) {
249 if (likely(rl->lcn >= LCN_HOLE)) {
257 if (likely(rl->lcn != LCN_RL_NOT_MAPPED)) {
258 if (likely(rl->lcn == LCN_ENOENT))
264 if (!err && !is_retry) {
266 * The @vcn is in an unmapped region, map the runlist and
270 up_read(&ni->runlist.lock);
271 down_write(&ni->runlist.lock);
272 if (unlikely(ntfs_rl_vcn_to_lcn(ni->runlist.rl, vcn) !=
273 LCN_RL_NOT_MAPPED)) {
274 up_write(&ni->runlist.lock);
275 down_read(&ni->runlist.lock);
279 err = ntfs_map_runlist_nolock(ni, vcn);
281 up_write(&ni->runlist.lock);
282 down_read(&ni->runlist.lock);
289 * -EINVAL and -ENOENT coming from a failed mapping attempt are
290 * equivalent to i/o errors for us as they should not happen in
293 if (err == -EINVAL || err == -ENOENT)
298 ntfs_error(ni->vol->sb, "Failed with error code %i.", err);
303 * ntfs_attr_find - find (next) attribute in mft record
304 * @type: attribute type to find
305 * @name: attribute name to find (optional, i.e. NULL means don't care)
306 * @name_len: attribute name length (only needed if @name present)
307 * @ic: IGNORE_CASE or CASE_SENSITIVE (ignored if @name not present)
308 * @val: attribute value to find (optional, resident attributes only)
309 * @val_len: attribute value length
310 * @ctx: search context with mft record and attribute to search from
312 * You should not need to call this function directly. Use ntfs_attr_lookup()
315 * ntfs_attr_find() takes a search context @ctx as parameter and searches the
316 * mft record specified by @ctx->mrec, beginning at @ctx->attr, for an
317 * attribute of @type, optionally @name and @val.
319 * If the attribute is found, ntfs_attr_find() returns 0 and @ctx->attr will
320 * point to the found attribute.
322 * If the attribute is not found, ntfs_attr_find() returns -ENOENT and
323 * @ctx->attr will point to the attribute before which the attribute being
324 * searched for would need to be inserted if such an action were to be desired.
326 * On actual error, ntfs_attr_find() returns -EIO. In this case @ctx->attr is
327 * undefined and in particular do not rely on it not changing.
329 * If @ctx->is_first is TRUE, the search begins with @ctx->attr itself. If it
330 * is FALSE, the search begins after @ctx->attr.
332 * If @ic is IGNORE_CASE, the @name comparisson is not case sensitive and
333 * @ctx->ntfs_ino must be set to the ntfs inode to which the mft record
334 * @ctx->mrec belongs. This is so we can get at the ntfs volume and hence at
335 * the upcase table. If @ic is CASE_SENSITIVE, the comparison is case
336 * sensitive. When @name is present, @name_len is the @name length in Unicode
339 * If @name is not present (NULL), we assume that the unnamed attribute is
340 * being searched for.
342 * Finally, the resident attribute value @val is looked for, if present. If
343 * @val is not present (NULL), @val_len is ignored.
345 * ntfs_attr_find() only searches the specified mft record and it ignores the
346 * presence of an attribute list attribute (unless it is the one being searched
347 * for, obviously). If you need to take attribute lists into consideration,
348 * use ntfs_attr_lookup() instead (see below). This also means that you cannot
349 * use ntfs_attr_find() to search for extent records of non-resident
350 * attributes, as extents with lowest_vcn != 0 are usually described by the
351 * attribute list attribute only. - Note that it is possible that the first
352 * extent is only in the attribute list while the last extent is in the base
353 * mft record, so do not rely on being able to find the first extent in the
356 * Warning: Never use @val when looking for attribute types which can be
357 * non-resident as this most likely will result in a crash!
359 static int ntfs_attr_find(const ATTR_TYPE type, const ntfschar *name,
360 const u32 name_len, const IGNORE_CASE_BOOL ic,
361 const u8 *val, const u32 val_len, ntfs_attr_search_ctx *ctx)
364 ntfs_volume *vol = ctx->ntfs_ino->vol;
365 ntfschar *upcase = vol->upcase;
366 u32 upcase_len = vol->upcase_len;
369 * Iterate over attributes in mft record starting at @ctx->attr, or the
370 * attribute following that, if @ctx->is_first is TRUE.
374 ctx->is_first = FALSE;
376 a = (ATTR_RECORD*)((u8*)ctx->attr +
377 le32_to_cpu(ctx->attr->length));
378 for (;; a = (ATTR_RECORD*)((u8*)a + le32_to_cpu(a->length))) {
379 if ((u8*)a < (u8*)ctx->mrec || (u8*)a > (u8*)ctx->mrec +
380 le32_to_cpu(ctx->mrec->bytes_allocated))
383 if (unlikely(le32_to_cpu(a->type) > le32_to_cpu(type) ||
386 if (unlikely(!a->length))
391 * If @name is present, compare the two names. If @name is
392 * missing, assume we want an unnamed attribute.
395 /* The search failed if the found attribute is named. */
398 } else if (!ntfs_are_names_equal(name, name_len,
399 (ntfschar*)((u8*)a + le16_to_cpu(a->name_offset)),
400 a->name_length, ic, upcase, upcase_len)) {
403 rc = ntfs_collate_names(name, name_len,
405 le16_to_cpu(a->name_offset)),
406 a->name_length, 1, IGNORE_CASE,
409 * If @name collates before a->name, there is no
410 * matching attribute.
414 /* If the strings are not equal, continue search. */
417 rc = ntfs_collate_names(name, name_len,
419 le16_to_cpu(a->name_offset)),
420 a->name_length, 1, CASE_SENSITIVE,
428 * The names match or @name not present and attribute is
429 * unnamed. If no @val specified, we have found the attribute
434 /* @val is present; compare values. */
438 rc = memcmp(val, (u8*)a + le16_to_cpu(
439 a->data.resident.value_offset),
440 min_t(u32, val_len, le32_to_cpu(
441 a->data.resident.value_length)));
443 * If @val collates before the current attribute's
444 * value, there is no matching attribute.
450 a->data.resident.value_length);
459 ntfs_error(vol->sb, "Inode is corrupt. Run chkdsk.");
465 * load_attribute_list - load an attribute list into memory
466 * @vol: ntfs volume from which to read
467 * @runlist: runlist of the attribute list
468 * @al_start: destination buffer
469 * @size: size of the destination buffer in bytes
470 * @initialized_size: initialized size of the attribute list
472 * Walk the runlist @runlist and load all clusters from it copying them into
473 * the linear buffer @al. The maximum number of bytes copied to @al is @size
474 * bytes. Note, @size does not need to be a multiple of the cluster size. If
475 * @initialized_size is less than @size, the region in @al between
476 * @initialized_size and @size will be zeroed and not read from disk.
478 * Return 0 on success or -errno on error.
480 int load_attribute_list(ntfs_volume *vol, runlist *runlist, u8 *al_start,
481 const s64 size, const s64 initialized_size)
485 u8 *al_end = al + initialized_size;
487 struct buffer_head *bh;
488 struct super_block *sb;
489 unsigned long block_size;
490 unsigned long block, max_block;
492 unsigned char block_size_bits;
494 ntfs_debug("Entering.");
495 if (!vol || !runlist || !al || size <= 0 || initialized_size < 0 ||
496 initialized_size > size)
498 if (!initialized_size) {
503 block_size = sb->s_blocksize;
504 block_size_bits = sb->s_blocksize_bits;
505 down_read(&runlist->lock);
507 /* Read all clusters specified by the runlist one run at a time. */
509 lcn = ntfs_rl_vcn_to_lcn(rl, rl->vcn);
510 ntfs_debug("Reading vcn = 0x%llx, lcn = 0x%llx.",
511 (unsigned long long)rl->vcn,
512 (unsigned long long)lcn);
513 /* The attribute list cannot be sparse. */
515 ntfs_error(sb, "ntfs_rl_vcn_to_lcn() failed. Cannot "
516 "read attribute list.");
519 block = lcn << vol->cluster_size_bits >> block_size_bits;
520 /* Read the run from device in chunks of block_size bytes. */
521 max_block = block + (rl->length << vol->cluster_size_bits >>
523 ntfs_debug("max_block = 0x%lx.", max_block);
525 ntfs_debug("Reading block = 0x%lx.", block);
526 bh = sb_bread(sb, block);
528 ntfs_error(sb, "sb_bread() failed. Cannot "
529 "read attribute list.");
532 if (al + block_size >= al_end)
534 memcpy(al, bh->b_data, block_size);
537 } while (++block < max_block);
540 if (initialized_size < size) {
542 memset(al_start + initialized_size, 0, size - initialized_size);
545 up_read(&runlist->lock);
552 * Note: The attribute list can be smaller than its allocation
553 * by multiple clusters. This has been encountered by at least
554 * two people running Windows XP, thus we cannot do any
555 * truncation sanity checking here. (AIA)
557 memcpy(al, bh->b_data, al_end - al);
559 if (initialized_size < size)
565 ntfs_error(sb, "Attribute list buffer overflow. Read attribute list "
573 * ntfs_external_attr_find - find an attribute in the attribute list of an inode
574 * @type: attribute type to find
575 * @name: attribute name to find (optional, i.e. NULL means don't care)
576 * @name_len: attribute name length (only needed if @name present)
577 * @ic: IGNORE_CASE or CASE_SENSITIVE (ignored if @name not present)
578 * @lowest_vcn: lowest vcn to find (optional, non-resident attributes only)
579 * @val: attribute value to find (optional, resident attributes only)
580 * @val_len: attribute value length
581 * @ctx: search context with mft record and attribute to search from
583 * You should not need to call this function directly. Use ntfs_attr_lookup()
586 * Find an attribute by searching the attribute list for the corresponding
587 * attribute list entry. Having found the entry, map the mft record if the
588 * attribute is in a different mft record/inode, ntfs_attr_find() the attribute
589 * in there and return it.
591 * On first search @ctx->ntfs_ino must be the base mft record and @ctx must
592 * have been obtained from a call to ntfs_attr_get_search_ctx(). On subsequent
593 * calls @ctx->ntfs_ino can be any extent inode, too (@ctx->base_ntfs_ino is
594 * then the base inode).
596 * After finishing with the attribute/mft record you need to call
597 * ntfs_attr_put_search_ctx() to cleanup the search context (unmapping any
598 * mapped inodes, etc).
600 * If the attribute is found, ntfs_external_attr_find() returns 0 and
601 * @ctx->attr will point to the found attribute. @ctx->mrec will point to the
602 * mft record in which @ctx->attr is located and @ctx->al_entry will point to
603 * the attribute list entry for the attribute.
605 * If the attribute is not found, ntfs_external_attr_find() returns -ENOENT and
606 * @ctx->attr will point to the attribute in the base mft record before which
607 * the attribute being searched for would need to be inserted if such an action
608 * were to be desired. @ctx->mrec will point to the mft record in which
609 * @ctx->attr is located and @ctx->al_entry will point to the attribute list
610 * entry of the attribute before which the attribute being searched for would
611 * need to be inserted if such an action were to be desired.
613 * Thus to insert the not found attribute, one wants to add the attribute to
614 * @ctx->mrec (the base mft record) and if there is not enough space, the
615 * attribute should be placed in a newly allocated extent mft record. The
616 * attribute list entry for the inserted attribute should be inserted in the
617 * attribute list attribute at @ctx->al_entry.
619 * On actual error, ntfs_external_attr_find() returns -EIO. In this case
620 * @ctx->attr is undefined and in particular do not rely on it not changing.
622 static int ntfs_external_attr_find(const ATTR_TYPE type,
623 const ntfschar *name, const u32 name_len,
624 const IGNORE_CASE_BOOL ic, const VCN lowest_vcn,
625 const u8 *val, const u32 val_len, ntfs_attr_search_ctx *ctx)
627 ntfs_inode *base_ni, *ni;
629 ATTR_LIST_ENTRY *al_entry, *next_al_entry;
630 u8 *al_start, *al_end;
635 static const char *es = " Unmount and run chkdsk.";
638 base_ni = ctx->base_ntfs_ino;
639 ntfs_debug("Entering for inode 0x%lx, type 0x%x.", ni->mft_no, type);
641 /* First call happens with the base mft record. */
642 base_ni = ctx->base_ntfs_ino = ctx->ntfs_ino;
643 ctx->base_mrec = ctx->mrec;
646 ctx->base_attr = ctx->attr;
650 al_start = base_ni->attr_list;
651 al_end = al_start + base_ni->attr_list_size;
653 ctx->al_entry = (ATTR_LIST_ENTRY*)al_start;
655 * Iterate over entries in attribute list starting at @ctx->al_entry,
656 * or the entry following that, if @ctx->is_first is TRUE.
659 al_entry = ctx->al_entry;
660 ctx->is_first = FALSE;
662 al_entry = (ATTR_LIST_ENTRY*)((u8*)ctx->al_entry +
663 le16_to_cpu(ctx->al_entry->length));
664 for (;; al_entry = next_al_entry) {
665 /* Out of bounds check. */
666 if ((u8*)al_entry < base_ni->attr_list ||
667 (u8*)al_entry > al_end)
668 break; /* Inode is corrupt. */
669 ctx->al_entry = al_entry;
670 /* Catch the end of the attribute list. */
671 if ((u8*)al_entry == al_end)
673 if (!al_entry->length)
675 if ((u8*)al_entry + 6 > al_end || (u8*)al_entry +
676 le16_to_cpu(al_entry->length) > al_end)
678 next_al_entry = (ATTR_LIST_ENTRY*)((u8*)al_entry +
679 le16_to_cpu(al_entry->length));
680 if (le32_to_cpu(al_entry->type) > le32_to_cpu(type))
682 if (type != al_entry->type)
685 * If @name is present, compare the two names. If @name is
686 * missing, assume we want an unnamed attribute.
688 al_name_len = al_entry->name_length;
689 al_name = (ntfschar*)((u8*)al_entry + al_entry->name_offset);
693 } else if (!ntfs_are_names_equal(al_name, al_name_len, name,
694 name_len, ic, vol->upcase, vol->upcase_len)) {
697 rc = ntfs_collate_names(name, name_len, al_name,
698 al_name_len, 1, IGNORE_CASE,
699 vol->upcase, vol->upcase_len);
701 * If @name collates before al_name, there is no
702 * matching attribute.
706 /* If the strings are not equal, continue search. */
710 * FIXME: Reverse engineering showed 0, IGNORE_CASE but
711 * that is inconsistent with ntfs_attr_find(). The
712 * subsequent rc checks were also different. Perhaps I
713 * made a mistake in one of the two. Need to recheck
714 * which is correct or at least see what is going on...
717 rc = ntfs_collate_names(name, name_len, al_name,
718 al_name_len, 1, CASE_SENSITIVE,
719 vol->upcase, vol->upcase_len);
726 * The names match or @name not present and attribute is
727 * unnamed. Now check @lowest_vcn. Continue search if the
728 * next attribute list entry still fits @lowest_vcn. Otherwise
729 * we have reached the right one or the search has failed.
731 if (lowest_vcn && (u8*)next_al_entry >= al_start &&
732 (u8*)next_al_entry + 6 < al_end &&
733 (u8*)next_al_entry + le16_to_cpu(
734 next_al_entry->length) <= al_end &&
735 sle64_to_cpu(next_al_entry->lowest_vcn) <=
737 next_al_entry->type == al_entry->type &&
738 next_al_entry->name_length == al_name_len &&
739 ntfs_are_names_equal((ntfschar*)((u8*)
741 next_al_entry->name_offset),
742 next_al_entry->name_length,
743 al_name, al_name_len, CASE_SENSITIVE,
744 vol->upcase, vol->upcase_len))
746 if (MREF_LE(al_entry->mft_reference) == ni->mft_no) {
747 if (MSEQNO_LE(al_entry->mft_reference) != ni->seq_no) {
748 ntfs_error(vol->sb, "Found stale mft "
749 "reference in attribute list "
750 "of base inode 0x%lx.%s",
751 base_ni->mft_no, es);
755 } else { /* Mft references do not match. */
756 /* If there is a mapped record unmap it first. */
758 unmap_extent_mft_record(ni);
759 /* Do we want the base record back? */
760 if (MREF_LE(al_entry->mft_reference) ==
762 ni = ctx->ntfs_ino = base_ni;
763 ctx->mrec = ctx->base_mrec;
765 /* We want an extent record. */
766 ctx->mrec = map_extent_mft_record(base_ni,
768 al_entry->mft_reference), &ni);
769 if (IS_ERR(ctx->mrec)) {
770 ntfs_error(vol->sb, "Failed to map "
772 "0x%lx of base inode "
776 base_ni->mft_no, es);
777 err = PTR_ERR(ctx->mrec);
780 /* Cause @ctx to be sanitized below. */
786 ctx->attr = (ATTR_RECORD*)((u8*)ctx->mrec +
787 le16_to_cpu(ctx->mrec->attrs_offset));
790 * ctx->vfs_ino, ctx->mrec, and ctx->attr now point to the
791 * mft record containing the attribute represented by the
795 * We could call into ntfs_attr_find() to find the right
796 * attribute in this mft record but this would be less
797 * efficient and not quite accurate as ntfs_attr_find() ignores
798 * the attribute instance numbers for example which become
799 * important when one plays with attribute lists. Also,
800 * because a proper match has been found in the attribute list
801 * entry above, the comparison can now be optimized. So it is
802 * worth re-implementing a simplified ntfs_attr_find() here.
806 * Use a manual loop so we can still use break and continue
807 * with the same meanings as above.
810 if ((u8*)a < (u8*)ctx->mrec || (u8*)a > (u8*)ctx->mrec +
811 le32_to_cpu(ctx->mrec->bytes_allocated))
813 if (a->type == AT_END)
817 if (al_entry->instance != a->instance)
820 * If the type and/or the name are mismatched between the
821 * attribute list entry and the attribute record, there is
822 * corruption so we break and return error EIO.
824 if (al_entry->type != a->type)
826 if (!ntfs_are_names_equal((ntfschar*)((u8*)a +
827 le16_to_cpu(a->name_offset)), a->name_length,
828 al_name, al_name_len, CASE_SENSITIVE,
829 vol->upcase, vol->upcase_len))
833 * If no @val specified or @val specified and it matches, we
836 if (!val || (!a->non_resident && le32_to_cpu(
837 a->data.resident.value_length) == val_len &&
839 le16_to_cpu(a->data.resident.value_offset),
841 ntfs_debug("Done, found.");
845 /* Proceed to the next attribute in the current mft record. */
846 a = (ATTR_RECORD*)((u8*)a + le32_to_cpu(a->length));
847 goto do_next_attr_loop;
850 ntfs_error(vol->sb, "Base inode 0x%lx contains corrupt "
851 "attribute list attribute.%s", base_ni->mft_no,
857 unmap_extent_mft_record(ni);
858 ctx->ntfs_ino = base_ni;
859 ctx->mrec = ctx->base_mrec;
860 ctx->attr = ctx->base_attr;
867 * If we were looking for AT_END, we reset the search context @ctx and
868 * use ntfs_attr_find() to seek to the end of the base mft record.
870 if (type == AT_END) {
871 ntfs_attr_reinit_search_ctx(ctx);
872 return ntfs_attr_find(AT_END, name, name_len, ic, val, val_len,
876 * The attribute was not found. Before we return, we want to ensure
877 * @ctx->mrec and @ctx->attr indicate the position at which the
878 * attribute should be inserted in the base mft record. Since we also
879 * want to preserve @ctx->al_entry we cannot reinitialize the search
880 * context using ntfs_attr_reinit_search_ctx() as this would set
881 * @ctx->al_entry to NULL. Thus we do the necessary bits manually (see
882 * ntfs_attr_init_search_ctx() below). Note, we _only_ preserve
883 * @ctx->al_entry as the remaining fields (base_*) are identical to
884 * their non base_ counterparts and we cannot set @ctx->base_attr
885 * correctly yet as we do not know what @ctx->attr will be set to by
886 * the call to ntfs_attr_find() below.
889 unmap_extent_mft_record(ni);
890 ctx->mrec = ctx->base_mrec;
891 ctx->attr = (ATTR_RECORD*)((u8*)ctx->mrec +
892 le16_to_cpu(ctx->mrec->attrs_offset));
893 ctx->is_first = TRUE;
894 ctx->ntfs_ino = base_ni;
895 ctx->base_ntfs_ino = NULL;
896 ctx->base_mrec = NULL;
897 ctx->base_attr = NULL;
899 * In case there are multiple matches in the base mft record, need to
900 * keep enumerating until we get an attribute not found response (or
901 * another error), otherwise we would keep returning the same attribute
902 * over and over again and all programs using us for enumeration would
903 * lock up in a tight loop.
906 err = ntfs_attr_find(type, name, name_len, ic, val, val_len,
909 ntfs_debug("Done, not found.");
914 * ntfs_attr_lookup - find an attribute in an ntfs inode
915 * @type: attribute type to find
916 * @name: attribute name to find (optional, i.e. NULL means don't care)
917 * @name_len: attribute name length (only needed if @name present)
918 * @ic: IGNORE_CASE or CASE_SENSITIVE (ignored if @name not present)
919 * @lowest_vcn: lowest vcn to find (optional, non-resident attributes only)
920 * @val: attribute value to find (optional, resident attributes only)
921 * @val_len: attribute value length
922 * @ctx: search context with mft record and attribute to search from
924 * Find an attribute in an ntfs inode. On first search @ctx->ntfs_ino must
925 * be the base mft record and @ctx must have been obtained from a call to
926 * ntfs_attr_get_search_ctx().
928 * This function transparently handles attribute lists and @ctx is used to
929 * continue searches where they were left off at.
931 * After finishing with the attribute/mft record you need to call
932 * ntfs_attr_put_search_ctx() to cleanup the search context (unmapping any
933 * mapped inodes, etc).
935 * Return 0 if the search was successful and -errno if not.
937 * When 0, @ctx->attr is the found attribute and it is in mft record
938 * @ctx->mrec. If an attribute list attribute is present, @ctx->al_entry is
939 * the attribute list entry of the found attribute.
941 * When -ENOENT, @ctx->attr is the attribute which collates just after the
942 * attribute being searched for, i.e. if one wants to add the attribute to the
943 * mft record this is the correct place to insert it into. If an attribute
944 * list attribute is present, @ctx->al_entry is the attribute list entry which
945 * collates just after the attribute list entry of the attribute being searched
946 * for, i.e. if one wants to add the attribute to the mft record this is the
947 * correct place to insert its attribute list entry into.
949 * When -errno != -ENOENT, an error occured during the lookup. @ctx->attr is
950 * then undefined and in particular you should not rely on it not changing.
952 int ntfs_attr_lookup(const ATTR_TYPE type, const ntfschar *name,
953 const u32 name_len, const IGNORE_CASE_BOOL ic,
954 const VCN lowest_vcn, const u8 *val, const u32 val_len,
955 ntfs_attr_search_ctx *ctx)
959 ntfs_debug("Entering.");
960 if (ctx->base_ntfs_ino)
961 base_ni = ctx->base_ntfs_ino;
963 base_ni = ctx->ntfs_ino;
964 /* Sanity check, just for debugging really. */
966 if (!NInoAttrList(base_ni) || type == AT_ATTRIBUTE_LIST)
967 return ntfs_attr_find(type, name, name_len, ic, val, val_len,
969 return ntfs_external_attr_find(type, name, name_len, ic, lowest_vcn,
974 * ntfs_attr_init_search_ctx - initialize an attribute search context
975 * @ctx: attribute search context to initialize
976 * @ni: ntfs inode with which to initialize the search context
977 * @mrec: mft record with which to initialize the search context
979 * Initialize the attribute search context @ctx with @ni and @mrec.
981 static inline void ntfs_attr_init_search_ctx(ntfs_attr_search_ctx *ctx,
982 ntfs_inode *ni, MFT_RECORD *mrec)
985 /* Sanity checks are performed elsewhere. */
986 ctx->attr = (ATTR_RECORD*)((u8*)mrec + le16_to_cpu(mrec->attrs_offset));
987 ctx->is_first = TRUE;
989 ctx->al_entry = NULL;
990 ctx->base_ntfs_ino = NULL;
991 ctx->base_mrec = NULL;
992 ctx->base_attr = NULL;
996 * ntfs_attr_reinit_search_ctx - reinitialize an attribute search context
997 * @ctx: attribute search context to reinitialize
999 * Reinitialize the attribute search context @ctx, unmapping an associated
1000 * extent mft record if present, and initialize the search context again.
1002 * This is used when a search for a new attribute is being started to reset
1003 * the search context to the beginning.
1005 void ntfs_attr_reinit_search_ctx(ntfs_attr_search_ctx *ctx)
1007 if (likely(!ctx->base_ntfs_ino)) {
1008 /* No attribute list. */
1009 ctx->is_first = TRUE;
1010 /* Sanity checks are performed elsewhere. */
1011 ctx->attr = (ATTR_RECORD*)((u8*)ctx->mrec +
1012 le16_to_cpu(ctx->mrec->attrs_offset));
1014 * This needs resetting due to ntfs_external_attr_find() which
1015 * can leave it set despite having zeroed ctx->base_ntfs_ino.
1017 ctx->al_entry = NULL;
1019 } /* Attribute list. */
1020 if (ctx->ntfs_ino != ctx->base_ntfs_ino)
1021 unmap_extent_mft_record(ctx->ntfs_ino);
1022 ntfs_attr_init_search_ctx(ctx, ctx->base_ntfs_ino, ctx->base_mrec);
1027 * ntfs_attr_get_search_ctx - allocate/initialize a new attribute search context
1028 * @ni: ntfs inode with which to initialize the search context
1029 * @mrec: mft record with which to initialize the search context
1031 * Allocate a new attribute search context, initialize it with @ni and @mrec,
1032 * and return it. Return NULL if allocation failed.
1034 ntfs_attr_search_ctx *ntfs_attr_get_search_ctx(ntfs_inode *ni, MFT_RECORD *mrec)
1036 ntfs_attr_search_ctx *ctx;
1038 ctx = kmem_cache_alloc(ntfs_attr_ctx_cache, SLAB_NOFS);
1040 ntfs_attr_init_search_ctx(ctx, ni, mrec);
1045 * ntfs_attr_put_search_ctx - release an attribute search context
1046 * @ctx: attribute search context to free
1048 * Release the attribute search context @ctx, unmapping an associated extent
1049 * mft record if present.
1051 void ntfs_attr_put_search_ctx(ntfs_attr_search_ctx *ctx)
1053 if (ctx->base_ntfs_ino && ctx->ntfs_ino != ctx->base_ntfs_ino)
1054 unmap_extent_mft_record(ctx->ntfs_ino);
1055 kmem_cache_free(ntfs_attr_ctx_cache, ctx);
1060 * ntfs_attr_find_in_attrdef - find an attribute in the $AttrDef system file
1061 * @vol: ntfs volume to which the attribute belongs
1062 * @type: attribute type which to find
1064 * Search for the attribute definition record corresponding to the attribute
1065 * @type in the $AttrDef system file.
1067 * Return the attribute type definition record if found and NULL if not found.
1069 static ATTR_DEF *ntfs_attr_find_in_attrdef(const ntfs_volume *vol,
1070 const ATTR_TYPE type)
1074 BUG_ON(!vol->attrdef);
1076 for (ad = vol->attrdef; (u8*)ad - (u8*)vol->attrdef <
1077 vol->attrdef_size && ad->type; ++ad) {
1078 /* We have not found it yet, carry on searching. */
1079 if (likely(le32_to_cpu(ad->type) < le32_to_cpu(type)))
1081 /* We found the attribute; return it. */
1082 if (likely(ad->type == type))
1084 /* We have gone too far already. No point in continuing. */
1087 /* Attribute not found. */
1088 ntfs_debug("Attribute type 0x%x not found in $AttrDef.",
1094 * ntfs_attr_size_bounds_check - check a size of an attribute type for validity
1095 * @vol: ntfs volume to which the attribute belongs
1096 * @type: attribute type which to check
1097 * @size: size which to check
1099 * Check whether the @size in bytes is valid for an attribute of @type on the
1100 * ntfs volume @vol. This information is obtained from $AttrDef system file.
1102 * Return 0 if valid, -ERANGE if not valid, or -ENOENT if the attribute is not
1103 * listed in $AttrDef.
1105 int ntfs_attr_size_bounds_check(const ntfs_volume *vol, const ATTR_TYPE type,
1112 * $ATTRIBUTE_LIST has a maximum size of 256kiB, but this is not
1113 * listed in $AttrDef.
1115 if (unlikely(type == AT_ATTRIBUTE_LIST && size > 256 * 1024))
1117 /* Get the $AttrDef entry for the attribute @type. */
1118 ad = ntfs_attr_find_in_attrdef(vol, type);
1121 /* Do the bounds check. */
1122 if (((sle64_to_cpu(ad->min_size) > 0) &&
1123 size < sle64_to_cpu(ad->min_size)) ||
1124 ((sle64_to_cpu(ad->max_size) > 0) && size >
1125 sle64_to_cpu(ad->max_size)))
1131 * ntfs_attr_can_be_non_resident - check if an attribute can be non-resident
1132 * @vol: ntfs volume to which the attribute belongs
1133 * @type: attribute type which to check
1135 * Check whether the attribute of @type on the ntfs volume @vol is allowed to
1136 * be non-resident. This information is obtained from $AttrDef system file.
1138 * Return 0 if the attribute is allowed to be non-resident, -EPERM if not, or
1139 * -ENOENT if the attribute is not listed in $AttrDef.
1141 int ntfs_attr_can_be_non_resident(const ntfs_volume *vol, const ATTR_TYPE type)
1146 * $DATA and $EA are always allowed to be non-resident even if $AttrDef
1147 * does not specify this in the flags of the $DATA attribute definition
1150 if (type == AT_DATA || type == AT_EA)
1152 /* Find the attribute definition record in $AttrDef. */
1153 ad = ntfs_attr_find_in_attrdef(vol, type);
1156 /* Check the flags and return the result. */
1157 if (ad->flags & CAN_BE_NON_RESIDENT)
1163 * ntfs_attr_can_be_resident - check if an attribute can be resident
1164 * @vol: ntfs volume to which the attribute belongs
1165 * @type: attribute type which to check
1167 * Check whether the attribute of @type on the ntfs volume @vol is allowed to
1168 * be resident. This information is derived from our ntfs knowledge and may
1169 * not be completely accurate, especially when user defined attributes are
1170 * present. Basically we allow everything to be resident except for index
1171 * allocation and $EA attributes.
1173 * Return 0 if the attribute is allowed to be non-resident and -EPERM if not.
1175 * Warning: In the system file $MFT the attribute $Bitmap must be non-resident
1176 * otherwise windows will not boot (blue screen of death)! We cannot
1177 * check for this here as we do not know which inode's $Bitmap is
1178 * being asked about so the caller needs to special case this.
1180 int ntfs_attr_can_be_resident(const ntfs_volume *vol, const ATTR_TYPE type)
1182 if (type != AT_INDEX_ALLOCATION && type != AT_EA)
1188 * ntfs_attr_record_resize - resize an attribute record
1189 * @m: mft record containing attribute record
1190 * @a: attribute record to resize
1191 * @new_size: new size in bytes to which to resize the attribute record @a
1193 * Resize the attribute record @a, i.e. the resident part of the attribute, in
1194 * the mft record @m to @new_size bytes.
1196 * Return 0 on success and -errno on error. The following error codes are
1198 * -ENOSPC - Not enough space in the mft record @m to perform the resize.
1200 * Note: On error, no modifications have been performed whatsoever.
1202 * Warning: If you make a record smaller without having copied all the data you
1203 * are interested in the data may be overwritten.
1205 int ntfs_attr_record_resize(MFT_RECORD *m, ATTR_RECORD *a, u32 new_size)
1207 ntfs_debug("Entering for new_size %u.", new_size);
1208 /* Align to 8 bytes if it is not already done. */
1210 new_size = (new_size + 7) & ~7;
1211 /* If the actual attribute length has changed, move things around. */
1212 if (new_size != le32_to_cpu(a->length)) {
1213 u32 new_muse = le32_to_cpu(m->bytes_in_use) -
1214 le32_to_cpu(a->length) + new_size;
1215 /* Not enough space in this mft record. */
1216 if (new_muse > le32_to_cpu(m->bytes_allocated))
1218 /* Move attributes following @a to their new location. */
1219 memmove((u8*)a + new_size, (u8*)a + le32_to_cpu(a->length),
1220 le32_to_cpu(m->bytes_in_use) - ((u8*)a -
1221 (u8*)m) - le32_to_cpu(a->length));
1222 /* Adjust @m to reflect the change in used space. */
1223 m->bytes_in_use = cpu_to_le32(new_muse);
1224 /* Adjust @a to reflect the new size. */
1225 if (new_size >= offsetof(ATTR_REC, length) + sizeof(a->length))
1226 a->length = cpu_to_le32(new_size);
1232 * ntfs_attr_make_non_resident - convert a resident to a non-resident attribute
1233 * @ni: ntfs inode describing the attribute to convert
1235 * Convert the resident ntfs attribute described by the ntfs inode @ni to a
1238 * Return 0 on success and -errno on error. The following error return codes
1240 * -EPERM - The attribute is not allowed to be non-resident.
1241 * -ENOMEM - Not enough memory.
1242 * -ENOSPC - Not enough disk space.
1243 * -EINVAL - Attribute not defined on the volume.
1244 * -EIO - I/o error or other error.
1246 * NOTE to self: No changes in the attribute list are required to move from
1247 * a resident to a non-resident attribute.
1249 * Locking: - The caller must hold i_sem on the inode.
1251 int ntfs_attr_make_non_resident(ntfs_inode *ni)
1254 struct inode *vi = VFS_I(ni);
1255 ntfs_volume *vol = ni->vol;
1256 ntfs_inode *base_ni;
1259 ntfs_attr_search_ctx *ctx;
1261 runlist_element *rl;
1263 unsigned long flags;
1264 int mp_size, mp_ofs, name_ofs, arec_size, err, err2;
1266 u8 old_res_attr_flags;
1268 /* Check that the attribute is allowed to be non-resident. */
1269 err = ntfs_attr_can_be_non_resident(vol, ni->type);
1270 if (unlikely(err)) {
1272 ntfs_debug("Attribute is not allowed to be "
1275 ntfs_debug("Attribute not defined on the NTFS "
1280 * The size needs to be aligned to a cluster boundary for allocation
1283 new_size = (i_size_read(vi) + vol->cluster_size - 1) &
1284 ~(vol->cluster_size - 1);
1287 * Will need the page later and since the page lock nests
1288 * outside all ntfs locks, we need to get the page now.
1290 page = find_or_create_page(vi->i_mapping, 0,
1291 mapping_gfp_mask(vi->i_mapping));
1292 if (unlikely(!page))
1294 /* Start by allocating clusters to hold the attribute value. */
1295 rl = ntfs_cluster_alloc(vol, 0, new_size >>
1296 vol->cluster_size_bits, -1, DATA_ZONE);
1299 ntfs_debug("Failed to allocate cluster%s, error code "
1300 "%i.\n", (new_size >>
1301 vol->cluster_size_bits) > 1 ? "s" : "",
1309 /* Determine the size of the mapping pairs array. */
1310 mp_size = ntfs_get_size_for_mapping_pairs(vol, rl, 0);
1311 if (unlikely(mp_size < 0)) {
1313 ntfs_debug("Failed to get size for mapping pairs array, error "
1317 down_write(&ni->runlist.lock);
1321 base_ni = ni->ext.base_ntfs_ino;
1322 m = map_mft_record(base_ni);
1329 ctx = ntfs_attr_get_search_ctx(base_ni, m);
1330 if (unlikely(!ctx)) {
1334 err = ntfs_attr_lookup(ni->type, ni->name, ni->name_len,
1335 CASE_SENSITIVE, 0, NULL, 0, ctx);
1336 if (unlikely(err)) {
1343 BUG_ON(NInoNonResident(ni));
1344 BUG_ON(a->non_resident);
1346 * Calculate new offsets for the name and the mapping pairs array.
1347 * We assume the attribute is not compressed or sparse.
1349 name_ofs = (offsetof(ATTR_REC,
1350 data.non_resident.compressed_size) + 7) & ~7;
1351 mp_ofs = (name_ofs + a->name_length * sizeof(ntfschar) + 7) & ~7;
1353 * Determine the size of the resident part of the now non-resident
1356 arec_size = (mp_ofs + mp_size + 7) & ~7;
1358 * If the page is not uptodate bring it uptodate by copying from the
1361 attr_size = le32_to_cpu(a->data.resident.value_length);
1362 BUG_ON(attr_size != i_size_read(vi));
1363 if (page && !PageUptodate(page)) {
1364 kaddr = kmap_atomic(page, KM_USER0);
1365 memcpy(kaddr, (u8*)a +
1366 le16_to_cpu(a->data.resident.value_offset),
1368 memset(kaddr + attr_size, 0, PAGE_CACHE_SIZE - attr_size);
1369 kunmap_atomic(kaddr, KM_USER0);
1370 flush_dcache_page(page);
1371 SetPageUptodate(page);
1373 /* Backup the attribute flag. */
1374 old_res_attr_flags = a->data.resident.flags;
1375 /* Resize the resident part of the attribute record. */
1376 err = ntfs_attr_record_resize(m, a, arec_size);
1380 * Convert the resident part of the attribute record to describe a
1381 * non-resident attribute.
1383 a->non_resident = 1;
1384 /* Move the attribute name if it exists and update the offset. */
1386 memmove((u8*)a + name_ofs, (u8*)a + le16_to_cpu(a->name_offset),
1387 a->name_length * sizeof(ntfschar));
1388 a->name_offset = cpu_to_le16(name_ofs);
1390 * FIXME: For now just clear all of these as we do not support them
1393 a->flags &= cpu_to_le16(0xffff & ~le16_to_cpu(ATTR_IS_SPARSE |
1394 ATTR_IS_ENCRYPTED | ATTR_COMPRESSION_MASK));
1395 /* Setup the fields specific to non-resident attributes. */
1396 a->data.non_resident.lowest_vcn = 0;
1397 a->data.non_resident.highest_vcn = cpu_to_sle64((new_size - 1) >>
1398 vol->cluster_size_bits);
1399 a->data.non_resident.mapping_pairs_offset = cpu_to_le16(mp_ofs);
1400 a->data.non_resident.compression_unit = 0;
1401 memset(&a->data.non_resident.reserved, 0,
1402 sizeof(a->data.non_resident.reserved));
1403 a->data.non_resident.allocated_size = cpu_to_sle64(new_size);
1404 a->data.non_resident.data_size =
1405 a->data.non_resident.initialized_size =
1406 cpu_to_sle64(attr_size);
1407 /* Generate the mapping pairs array into the attribute record. */
1408 err = ntfs_mapping_pairs_build(vol, (u8*)a + mp_ofs,
1409 arec_size - mp_ofs, rl, 0, NULL);
1410 if (unlikely(err)) {
1411 ntfs_debug("Failed to build mapping pairs, error code %i.",
1415 /* Setup the in-memory attribute structure to be non-resident. */
1417 * FIXME: For now just clear all of these as we do not support them
1420 NInoClearSparse(ni);
1421 NInoClearEncrypted(ni);
1422 NInoClearCompressed(ni);
1423 ni->runlist.rl = rl;
1424 write_lock_irqsave(&ni->size_lock, flags);
1425 ni->allocated_size = new_size;
1426 write_unlock_irqrestore(&ni->size_lock, flags);
1428 * This needs to be last since the address space operations ->readpage
1429 * and ->writepage can run concurrently with us as they are not
1430 * serialized on i_sem. Note, we are not allowed to fail once we flip
1431 * this switch, which is another reason to do this last.
1433 NInoSetNonResident(ni);
1434 /* Mark the mft record dirty, so it gets written back. */
1435 flush_dcache_mft_record_page(ctx->ntfs_ino);
1436 mark_mft_record_dirty(ctx->ntfs_ino);
1437 ntfs_attr_put_search_ctx(ctx);
1438 unmap_mft_record(base_ni);
1439 up_write(&ni->runlist.lock);
1441 set_page_dirty(page);
1443 mark_page_accessed(page);
1444 page_cache_release(page);
1446 ntfs_debug("Done.");
1449 /* Convert the attribute back into a resident attribute. */
1450 a->non_resident = 0;
1451 /* Move the attribute name if it exists and update the offset. */
1452 name_ofs = (offsetof(ATTR_RECORD, data.resident.reserved) +
1453 sizeof(a->data.resident.reserved) + 7) & ~7;
1455 memmove((u8*)a + name_ofs, (u8*)a + le16_to_cpu(a->name_offset),
1456 a->name_length * sizeof(ntfschar));
1457 mp_ofs = (name_ofs + a->name_length * sizeof(ntfschar) + 7) & ~7;
1458 a->name_offset = cpu_to_le16(name_ofs);
1459 arec_size = (mp_ofs + attr_size + 7) & ~7;
1460 /* Resize the resident part of the attribute record. */
1461 err2 = ntfs_attr_record_resize(m, a, arec_size);
1462 if (unlikely(err2)) {
1464 * This cannot happen (well if memory corruption is at work it
1465 * could happen in theory), but deal with it as well as we can.
1466 * If the old size is too small, truncate the attribute,
1467 * otherwise simply give it a larger allocated size.
1468 * FIXME: Should check whether chkdsk complains when the
1469 * allocated size is much bigger than the resident value size.
1471 arec_size = le32_to_cpu(a->length);
1472 if ((mp_ofs + attr_size) > arec_size) {
1474 attr_size = arec_size - mp_ofs;
1475 ntfs_error(vol->sb, "Failed to undo partial resident "
1476 "to non-resident attribute "
1477 "conversion. Truncating inode 0x%lx, "
1478 "attribute type 0x%x from %i bytes to "
1479 "%i bytes to maintain metadata "
1480 "consistency. THIS MEANS YOU ARE "
1481 "LOSING %i BYTES DATA FROM THIS %s.",
1483 (unsigned)le32_to_cpu(ni->type),
1484 err2, attr_size, err2 - attr_size,
1485 ((ni->type == AT_DATA) &&
1486 !ni->name_len) ? "FILE": "ATTRIBUTE");
1487 write_lock_irqsave(&ni->size_lock, flags);
1488 ni->initialized_size = attr_size;
1489 i_size_write(vi, attr_size);
1490 write_unlock_irqrestore(&ni->size_lock, flags);
1493 /* Setup the fields specific to resident attributes. */
1494 a->data.resident.value_length = cpu_to_le32(attr_size);
1495 a->data.resident.value_offset = cpu_to_le16(mp_ofs);
1496 a->data.resident.flags = old_res_attr_flags;
1497 memset(&a->data.resident.reserved, 0,
1498 sizeof(a->data.resident.reserved));
1499 /* Copy the data from the page back to the attribute value. */
1501 kaddr = kmap_atomic(page, KM_USER0);
1502 memcpy((u8*)a + mp_ofs, kaddr, attr_size);
1503 kunmap_atomic(kaddr, KM_USER0);
1505 /* Setup the allocated size in the ntfs inode in case it changed. */
1506 write_lock_irqsave(&ni->size_lock, flags);
1507 ni->allocated_size = arec_size - mp_ofs;
1508 write_unlock_irqrestore(&ni->size_lock, flags);
1509 /* Mark the mft record dirty, so it gets written back. */
1510 flush_dcache_mft_record_page(ctx->ntfs_ino);
1511 mark_mft_record_dirty(ctx->ntfs_ino);
1514 ntfs_attr_put_search_ctx(ctx);
1516 unmap_mft_record(base_ni);
1517 ni->runlist.rl = NULL;
1518 up_write(&ni->runlist.lock);
1521 if (ntfs_cluster_free_from_rl(vol, rl) < 0) {
1523 ntfs_error(vol->sb, "Failed to release allocated "
1524 "cluster(s) in error code path. Run "
1525 "chkdsk to recover the lost "
1531 page_cache_release(page);
1539 * ntfs_attr_set - fill (a part of) an attribute with a byte
1540 * @ni: ntfs inode describing the attribute to fill
1541 * @ofs: offset inside the attribute at which to start to fill
1542 * @cnt: number of bytes to fill
1543 * @val: the unsigned 8-bit value with which to fill the attribute
1545 * Fill @cnt bytes of the attribute described by the ntfs inode @ni starting at
1546 * byte offset @ofs inside the attribute with the constant byte @val.
1548 * This function is effectively like memset() applied to an ntfs attribute.
1549 * Note thie function actually only operates on the page cache pages belonging
1550 * to the ntfs attribute and it marks them dirty after doing the memset().
1551 * Thus it relies on the vm dirty page write code paths to cause the modified
1552 * pages to be written to the mft record/disk.
1554 * Return 0 on success and -errno on error. An error code of -ESPIPE means
1555 * that @ofs + @cnt were outside the end of the attribute and no write was
1558 int ntfs_attr_set(ntfs_inode *ni, const s64 ofs, const s64 cnt, const u8 val)
1560 ntfs_volume *vol = ni->vol;
1561 struct address_space *mapping;
1565 unsigned int start_ofs, end_ofs, size;
1567 ntfs_debug("Entering for ofs 0x%llx, cnt 0x%llx, val 0x%hx.",
1568 (long long)ofs, (long long)cnt, val);
1573 mapping = VFS_I(ni)->i_mapping;
1574 /* Work out the starting index and page offset. */
1575 idx = ofs >> PAGE_CACHE_SHIFT;
1576 start_ofs = ofs & ~PAGE_CACHE_MASK;
1577 /* Work out the ending index and page offset. */
1579 end_ofs = end & ~PAGE_CACHE_MASK;
1580 /* If the end is outside the inode size return -ESPIPE. */
1581 if (unlikely(end > i_size_read(VFS_I(ni)))) {
1582 ntfs_error(vol->sb, "Request exceeds end of attribute.");
1585 end >>= PAGE_CACHE_SHIFT;
1586 /* If there is a first partial page, need to do it the slow way. */
1588 page = read_cache_page(mapping, idx,
1589 (filler_t*)mapping->a_ops->readpage, NULL);
1591 ntfs_error(vol->sb, "Failed to read first partial "
1592 "page (sync error, index 0x%lx).", idx);
1593 return PTR_ERR(page);
1595 wait_on_page_locked(page);
1596 if (unlikely(!PageUptodate(page))) {
1597 ntfs_error(vol->sb, "Failed to read first partial page "
1598 "(async error, index 0x%lx).", idx);
1599 page_cache_release(page);
1600 return PTR_ERR(page);
1603 * If the last page is the same as the first page, need to
1604 * limit the write to the end offset.
1606 size = PAGE_CACHE_SIZE;
1609 kaddr = kmap_atomic(page, KM_USER0);
1610 memset(kaddr + start_ofs, val, size - start_ofs);
1611 flush_dcache_page(page);
1612 kunmap_atomic(kaddr, KM_USER0);
1613 set_page_dirty(page);
1614 page_cache_release(page);
1619 /* Do the whole pages the fast way. */
1620 for (; idx < end; idx++) {
1621 /* Find or create the current page. (The page is locked.) */
1622 page = grab_cache_page(mapping, idx);
1623 if (unlikely(!page)) {
1624 ntfs_error(vol->sb, "Insufficient memory to grab "
1625 "page (index 0x%lx).", idx);
1628 kaddr = kmap_atomic(page, KM_USER0);
1629 memset(kaddr, val, PAGE_CACHE_SIZE);
1630 flush_dcache_page(page);
1631 kunmap_atomic(kaddr, KM_USER0);
1633 * If the page has buffers, mark them uptodate since buffer
1634 * state and not page state is definitive in 2.6 kernels.
1636 if (page_has_buffers(page)) {
1637 struct buffer_head *bh, *head;
1639 bh = head = page_buffers(page);
1641 set_buffer_uptodate(bh);
1642 } while ((bh = bh->b_this_page) != head);
1644 /* Now that buffers are uptodate, set the page uptodate, too. */
1645 SetPageUptodate(page);
1647 * Set the page and all its buffers dirty and mark the inode
1648 * dirty, too. The VM will write the page later on.
1650 set_page_dirty(page);
1651 /* Finally unlock and release the page. */
1653 page_cache_release(page);
1655 /* If there is a last partial page, need to do it the slow way. */
1657 page = read_cache_page(mapping, idx,
1658 (filler_t*)mapping->a_ops->readpage, NULL);
1660 ntfs_error(vol->sb, "Failed to read last partial page "
1661 "(sync error, index 0x%lx).", idx);
1662 return PTR_ERR(page);
1664 wait_on_page_locked(page);
1665 if (unlikely(!PageUptodate(page))) {
1666 ntfs_error(vol->sb, "Failed to read last partial page "
1667 "(async error, index 0x%lx).", idx);
1668 page_cache_release(page);
1669 return PTR_ERR(page);
1671 kaddr = kmap_atomic(page, KM_USER0);
1672 memset(kaddr, val, end_ofs);
1673 flush_dcache_page(page);
1674 kunmap_atomic(kaddr, KM_USER0);
1675 set_page_dirty(page);
1676 page_cache_release(page);
1679 ntfs_debug("Done.");