diff options
Diffstat (limited to 'fs/ntfs/attrib.c')
| -rw-r--r-- | fs/ntfs/attrib.c | 2624 |
1 files changed, 0 insertions, 2624 deletions
diff --git a/fs/ntfs/attrib.c b/fs/ntfs/attrib.c deleted file mode 100644 index f79408f9127a..000000000000 --- a/fs/ntfs/attrib.c +++ /dev/null @@ -1,2624 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0-or-later -/* - * attrib.c - NTFS attribute operations. Part of the Linux-NTFS project. - * - * Copyright (c) 2001-2012 Anton Altaparmakov and Tuxera Inc. - * Copyright (c) 2002 Richard Russon - */ - -#include <linux/buffer_head.h> -#include <linux/sched.h> -#include <linux/slab.h> -#include <linux/swap.h> -#include <linux/writeback.h> - -#include "attrib.h" -#include "debug.h" -#include "layout.h" -#include "lcnalloc.h" -#include "malloc.h" -#include "mft.h" -#include "ntfs.h" -#include "types.h" - -/** - * ntfs_map_runlist_nolock - map (a part of) a runlist of an ntfs inode - * @ni: ntfs inode for which to map (part of) a runlist - * @vcn: map runlist part containing this vcn - * @ctx: active attribute search context if present or NULL if not - * - * Map the part of a runlist containing the @vcn of the ntfs inode @ni. - * - * If @ctx is specified, it is an active search context of @ni and its base mft - * record. This is needed when ntfs_map_runlist_nolock() encounters unmapped - * runlist fragments and allows their mapping. If you do not have the mft - * record mapped, you can specify @ctx as NULL and ntfs_map_runlist_nolock() - * will perform the necessary mapping and unmapping. - * - * Note, ntfs_map_runlist_nolock() saves the state of @ctx on entry and - * restores it before returning. Thus, @ctx will be left pointing to the same - * attribute on return as on entry. However, the actual pointers in @ctx may - * point to different memory locations on return, so you must remember to reset - * any cached pointers from the @ctx, i.e. after the call to - * ntfs_map_runlist_nolock(), you will probably want to do: - * m = ctx->mrec; - * a = ctx->attr; - * Assuming you cache ctx->attr in a variable @a of type ATTR_RECORD * and that - * you cache ctx->mrec in a variable @m of type MFT_RECORD *. - * - * Return 0 on success and -errno on error. There is one special error code - * which is not an error as such. This is -ENOENT. It means that @vcn is out - * of bounds of the runlist. - * - * Note the runlist can be NULL after this function returns if @vcn is zero and - * the attribute has zero allocated size, i.e. there simply is no runlist. - * - * WARNING: If @ctx is supplied, regardless of whether success or failure is - * returned, you need to check IS_ERR(@ctx->mrec) and if 'true' the @ctx - * is no longer valid, i.e. you need to either call - * ntfs_attr_reinit_search_ctx() or ntfs_attr_put_search_ctx() on it. - * In that case PTR_ERR(@ctx->mrec) will give you the error code for - * why the mapping of the old inode failed. - * - * Locking: - The runlist described by @ni must be locked for writing on entry - * and is locked on return. Note the runlist will be modified. - * - If @ctx is NULL, the base mft record of @ni must not be mapped on - * entry and it will be left unmapped on return. - * - If @ctx is not NULL, the base mft record must be mapped on entry - * and it will be left mapped on return. - */ -int ntfs_map_runlist_nolock(ntfs_inode *ni, VCN vcn, ntfs_attr_search_ctx *ctx) -{ - VCN end_vcn; - unsigned long flags; - ntfs_inode *base_ni; - MFT_RECORD *m; - ATTR_RECORD *a; - runlist_element *rl; - struct page *put_this_page = NULL; - int err = 0; - bool ctx_is_temporary, ctx_needs_reset; - ntfs_attr_search_ctx old_ctx = { NULL, }; - - ntfs_debug("Mapping runlist part containing vcn 0x%llx.", - (unsigned long long)vcn); - if (!NInoAttr(ni)) - base_ni = ni; - else - base_ni = ni->ext.base_ntfs_ino; - if (!ctx) { - ctx_is_temporary = ctx_needs_reset = true; - m = map_mft_record(base_ni); - if (IS_ERR(m)) - return PTR_ERR(m); - ctx = ntfs_attr_get_search_ctx(base_ni, m); - if (unlikely(!ctx)) { - err = -ENOMEM; - goto err_out; - } - } else { - VCN allocated_size_vcn; - - BUG_ON(IS_ERR(ctx->mrec)); - a = ctx->attr; - BUG_ON(!a->non_resident); - ctx_is_temporary = false; - end_vcn = sle64_to_cpu(a->data.non_resident.highest_vcn); - read_lock_irqsave(&ni->size_lock, flags); - allocated_size_vcn = ni->allocated_size >> - ni->vol->cluster_size_bits; - read_unlock_irqrestore(&ni->size_lock, flags); - if (!a->data.non_resident.lowest_vcn && end_vcn <= 0) - end_vcn = allocated_size_vcn - 1; - /* - * If we already have the attribute extent containing @vcn in - * @ctx, no need to look it up again. We slightly cheat in - * that if vcn exceeds the allocated size, we will refuse to - * map the runlist below, so there is definitely no need to get - * the right attribute extent. - */ - if (vcn >= allocated_size_vcn || (a->type == ni->type && - a->name_length == ni->name_len && - !memcmp((u8*)a + le16_to_cpu(a->name_offset), - ni->name, ni->name_len) && - sle64_to_cpu(a->data.non_resident.lowest_vcn) - <= vcn && end_vcn >= vcn)) - ctx_needs_reset = false; - else { - /* Save the old search context. */ - old_ctx = *ctx; - /* - * If the currently mapped (extent) inode is not the - * base inode we will unmap it when we reinitialize the - * search context which means we need to get a - * reference to the page containing the mapped mft - * record so we do not accidentally drop changes to the - * mft record when it has not been marked dirty yet. - */ - if (old_ctx.base_ntfs_ino && old_ctx.ntfs_ino != - old_ctx.base_ntfs_ino) { - put_this_page = old_ctx.ntfs_ino->page; - get_page(put_this_page); - } - /* - * Reinitialize the search context so we can lookup the - * needed attribute extent. - */ - ntfs_attr_reinit_search_ctx(ctx); - ctx_needs_reset = true; - } - } - if (ctx_needs_reset) { - err = ntfs_attr_lookup(ni->type, ni->name, ni->name_len, - CASE_SENSITIVE, vcn, NULL, 0, ctx); - if (unlikely(err)) { - if (err == -ENOENT) - err = -EIO; - goto err_out; - } - BUG_ON(!ctx->attr->non_resident); - } - a = ctx->attr; - /* - * Only decompress the mapping pairs if @vcn is inside it. Otherwise - * we get into problems when we try to map an out of bounds vcn because - * we then try to map the already mapped runlist fragment and - * ntfs_mapping_pairs_decompress() fails. - */ - end_vcn = sle64_to_cpu(a->data.non_resident.highest_vcn) + 1; - if (unlikely(vcn && vcn >= end_vcn)) { - err = -ENOENT; - goto err_out; - } - rl = ntfs_mapping_pairs_decompress(ni->vol, a, ni->runlist.rl); - if (IS_ERR(rl)) - err = PTR_ERR(rl); - else - ni->runlist.rl = rl; -err_out: - if (ctx_is_temporary) { - if (likely(ctx)) - ntfs_attr_put_search_ctx(ctx); - unmap_mft_record(base_ni); - } else if (ctx_needs_reset) { - /* - * If there is no attribute list, restoring the search context - * is accomplished simply by copying the saved context back over - * the caller supplied context. If there is an attribute list, - * things are more complicated as we need to deal with mapping - * of mft records and resulting potential changes in pointers. - */ - if (NInoAttrList(base_ni)) { - /* - * If the currently mapped (extent) inode is not the - * one we had before, we need to unmap it and map the - * old one. - */ - if (ctx->ntfs_ino != old_ctx.ntfs_ino) { - /* - * If the currently mapped inode is not the - * base inode, unmap it. - */ - if (ctx->base_ntfs_ino && ctx->ntfs_ino != - ctx->base_ntfs_ino) { - unmap_extent_mft_record(ctx->ntfs_ino); - ctx->mrec = ctx->base_mrec; - BUG_ON(!ctx->mrec); - } - /* - * If the old mapped inode is not the base - * inode, map it. - */ - if (old_ctx.base_ntfs_ino && - old_ctx.ntfs_ino != - old_ctx.base_ntfs_ino) { -retry_map: - ctx->mrec = map_mft_record( - old_ctx.ntfs_ino); - /* - * Something bad has happened. If out - * of memory retry till it succeeds. - * Any other errors are fatal and we - * return the error code in ctx->mrec. - * Let the caller deal with it... We - * just need to fudge things so the - * caller can reinit and/or put the - * search context safely. - */ - if (IS_ERR(ctx->mrec)) { - if (PTR_ERR(ctx->mrec) == - -ENOMEM) { - schedule(); - goto retry_map; - } else - old_ctx.ntfs_ino = - old_ctx. - base_ntfs_ino; - } - } - } - /* Update the changed pointers in the saved context. */ - if (ctx->mrec != old_ctx.mrec) { - if (!IS_ERR(ctx->mrec)) - old_ctx.attr = (ATTR_RECORD*)( - (u8*)ctx->mrec + - ((u8*)old_ctx.attr - - (u8*)old_ctx.mrec)); - old_ctx.mrec = ctx->mrec; - } - } - /* Restore the search context to the saved one. */ - *ctx = old_ctx; - /* - * We drop the reference on the page we took earlier. In the - * case that IS_ERR(ctx->mrec) is true this means we might lose - * some changes to the mft record that had been made between - * the last time it was marked dirty/written out and now. This - * at this stage is not a problem as the mapping error is fatal - * enough that the mft record cannot be written out anyway and - * the caller is very likely to shutdown the whole inode - * immediately and mark the volume dirty for chkdsk to pick up - * the pieces anyway. - */ - if (put_this_page) - put_page(put_this_page); - } - return err; -} - -/** - * ntfs_map_runlist - map (a part of) a runlist of an ntfs inode - * @ni: ntfs inode for which to map (part of) a runlist - * @vcn: map runlist part containing this vcn - * - * Map the part of a runlist containing the @vcn of the ntfs inode @ni. - * - * Return 0 on success and -errno on error. There is one special error code - * which is not an error as such. This is -ENOENT. It means that @vcn is out - * of bounds of the runlist. - * - * Locking: - The runlist must be unlocked on entry and is unlocked on return. - * - This function takes the runlist lock for writing and may modify - * the runlist. - */ -int ntfs_map_runlist(ntfs_inode *ni, VCN vcn) -{ - int err = 0; - - down_write(&ni->runlist.lock); - /* Make sure someone else didn't do the work while we were sleeping. */ - if (likely(ntfs_rl_vcn_to_lcn(ni->runlist.rl, vcn) <= - LCN_RL_NOT_MAPPED)) - err = ntfs_map_runlist_nolock(ni, vcn, NULL); - up_write(&ni->runlist.lock); - return err; -} - -/** - * ntfs_attr_vcn_to_lcn_nolock - convert a vcn into a lcn given an ntfs inode - * @ni: ntfs inode of the attribute whose runlist to search - * @vcn: vcn to convert - * @write_locked: true if the runlist is locked for writing - * - * Find the virtual cluster number @vcn in the runlist of the ntfs attribute - * described by the ntfs inode @ni and return the corresponding logical cluster - * number (lcn). - * - * If the @vcn is not mapped yet, the attempt is made to map the attribute - * extent containing the @vcn and the vcn to lcn conversion is retried. - * - * If @write_locked is true the caller has locked the runlist for writing and - * if false for reading. - * - * Since lcns must be >= 0, we use negative return codes with special meaning: - * - * Return code Meaning / Description - * ========================================== - * LCN_HOLE Hole / not allocated on disk. - * LCN_ENOENT There is no such vcn in the runlist, i.e. @vcn is out of bounds. - * LCN_ENOMEM Not enough memory to map runlist. - * LCN_EIO Critical error (runlist/file is corrupt, i/o error, etc). - * - * Locking: - The runlist must be locked on entry and is left locked on return. - * - If @write_locked is 'false', i.e. the runlist is locked for reading, - * the lock may be dropped inside the function so you cannot rely on - * the runlist still being the same when this function returns. - */ -LCN ntfs_attr_vcn_to_lcn_nolock(ntfs_inode *ni, const VCN vcn, - const bool write_locked) -{ - LCN lcn; - unsigned long flags; - bool is_retry = false; - - BUG_ON(!ni); - ntfs_debug("Entering for i_ino 0x%lx, vcn 0x%llx, %s_locked.", - ni->mft_no, (unsigned long long)vcn, - write_locked ? "write" : "read"); - BUG_ON(!NInoNonResident(ni)); - BUG_ON(vcn < 0); - if (!ni->runlist.rl) { - read_lock_irqsave(&ni->size_lock, flags); - if (!ni->allocated_size) { - read_unlock_irqrestore(&ni->size_lock, flags); - return LCN_ENOENT; - } - read_unlock_irqrestore(&ni->size_lock, flags); - } -retry_remap: - /* Convert vcn to lcn. If that fails map the runlist and retry once. */ - lcn = ntfs_rl_vcn_to_lcn(ni->runlist.rl, vcn); - if (likely(lcn >= LCN_HOLE)) { - ntfs_debug("Done, lcn 0x%llx.", (long long)lcn); - return lcn; - } - if (lcn != LCN_RL_NOT_MAPPED) { - if (lcn != LCN_ENOENT) - lcn = LCN_EIO; - } else if (!is_retry) { - int err; - - if (!write_locked) { - up_read(&ni->runlist.lock); - down_write(&ni->runlist.lock); - if (unlikely(ntfs_rl_vcn_to_lcn(ni->runlist.rl, vcn) != - LCN_RL_NOT_MAPPED)) { - up_write(&ni->runlist.lock); - down_read(&ni->runlist.lock); - goto retry_remap; - } - } - err = ntfs_map_runlist_nolock(ni, vcn, NULL); - if (!write_locked) { - up_write(&ni->runlist.lock); - down_read(&ni->runlist.lock); - } - if (likely(!err)) { - is_retry = true; - goto retry_remap; - } - if (err == -ENOENT) - lcn = LCN_ENOENT; - else if (err == -ENOMEM) - lcn = LCN_ENOMEM; - else - lcn = LCN_EIO; - } - if (lcn != LCN_ENOENT) - ntfs_error(ni->vol->sb, "Failed with error code %lli.", - (long long)lcn); - return lcn; -} - -/** - * ntfs_attr_find_vcn_nolock - find a vcn in the runlist of an ntfs inode - * @ni: ntfs inode describing the runlist to search - * @vcn: vcn to find - * @ctx: active attribute search context if present or NULL if not - * - * Find the virtual cluster number @vcn in the runlist described by the ntfs - * inode @ni and return the address of the runlist element containing the @vcn. - * - * If the @vcn is not mapped yet, the attempt is made to map the attribute - * extent containing the @vcn and the vcn to lcn conversion is retried. - * - * If @ctx is specified, it is an active search context of @ni and its base mft - * record. This is needed when ntfs_attr_find_vcn_nolock() encounters unmapped - * runlist fragments and allows their mapping. If you do not have the mft - * record mapped, you can specify @ctx as NULL and ntfs_attr_find_vcn_nolock() - * will perform the necessary mapping and unmapping. - * - * Note, ntfs_attr_find_vcn_nolock() saves the state of @ctx on entry and - * restores it before returning. Thus, @ctx will be left pointing to the same - * attribute on return as on entry. However, the actual pointers in @ctx may - * point to different memory locations on return, so you must remember to reset - * any cached pointers from the @ctx, i.e. after the call to - * ntfs_attr_find_vcn_nolock(), you will probably want to do: - * m = ctx->mrec; - * a = ctx->attr; - * Assuming you cache ctx->attr in a variable @a of type ATTR_RECORD * and that - * you cache ctx->mrec in a variable @m of type MFT_RECORD *. - * Note you need to distinguish between the lcn of the returned runlist element - * being >= 0 and LCN_HOLE. In the later case you have to return zeroes on - * read and allocate clusters on write. - * - * Return the runlist element containing the @vcn on success and - * ERR_PTR(-errno) on error. You need to test the return value with IS_ERR() - * to decide if the return is success or failure and PTR_ERR() to get to the - * error code if IS_ERR() is true. - * - * The possible error return codes are: - * -ENOENT - No such vcn in the runlist, i.e. @vcn is out of bounds. - * -ENOMEM - Not enough memory to map runlist. - * -EIO - Critical error (runlist/file is corrupt, i/o error, etc). - * - * WARNING: If @ctx is supplied, regardless of whether success or failure is - * returned, you need to check IS_ERR(@ctx->mrec) and if 'true' the @ctx - * is no longer valid, i.e. you need to either call - * ntfs_attr_reinit_search_ctx() or ntfs_attr_put_search_ctx() on it. - * In that case PTR_ERR(@ctx->mrec) will give you the error code for - * why the mapping of the old inode failed. - * - * Locking: - The runlist described by @ni must be locked for writing on entry - * and is locked on return. Note the runlist may be modified when - * needed runlist fragments need to be mapped. - * - If @ctx is NULL, the base mft record of @ni must not be mapped on - * entry and it will be left unmapped on return. - * - If @ctx is not NULL, the base mft record must be mapped on entry - * and it will be left mapped on return. - */ -runlist_element *ntfs_attr_find_vcn_nolock(ntfs_inode *ni, const VCN vcn, - ntfs_attr_search_ctx *ctx) -{ - unsigned long flags; - runlist_element *rl; - int err = 0; - bool is_retry = false; - - BUG_ON(!ni); - ntfs_debug("Entering for i_ino 0x%lx, vcn 0x%llx, with%s ctx.", - ni->mft_no, (unsigned long long)vcn, ctx ? "" : "out"); - BUG_ON(!NInoNonResident(ni)); - BUG_ON(vcn < 0); - if (!ni->runlist.rl) { - read_lock_irqsave(&ni->size_lock, flags); - if (!ni->allocated_size) { - read_unlock_irqrestore(&ni->size_lock, flags); - return ERR_PTR(-ENOENT); - } - read_unlock_irqrestore(&ni->size_lock, flags); - } -retry_remap: - rl = ni->runlist.rl; - if (likely(rl && vcn >= rl[0].vcn)) { - while (likely(rl->length)) { - if (unlikely(vcn < rl[1].vcn)) { - if (likely(rl->lcn >= LCN_HOLE)) { - ntfs_debug("Done."); - return rl; - } - break; - } - rl++; - } - if (likely(rl->lcn != LCN_RL_NOT_MAPPED)) { - if (likely(rl->lcn == LCN_ENOENT)) - err = -ENOENT; - else - err = -EIO; - } - } - if (!err && !is_retry) { - /* - * If the search context is invalid we cannot map the unmapped - * region. - */ - if (IS_ERR(ctx->mrec)) - err = PTR_ERR(ctx->mrec); - else { - /* - * The @vcn is in an unmapped region, map the runlist - * and retry. - */ - err = ntfs_map_runlist_nolock(ni, vcn, ctx); - if (likely(!err)) { - is_retry = true; - goto retry_remap; - } - } - if (err == -EINVAL) - err = -EIO; - } else if (!err) - err = -EIO; - if (err != -ENOENT) - ntfs_error(ni->vol->sb, "Failed with error code %i.", err); - return ERR_PTR(err); -} - -/** - * ntfs_attr_find - find (next) attribute in mft record - * @type: attribute type to find - * @name: attribute name to find (optional, i.e. NULL means don't care) - * @name_len: attribute name length (only needed if @name present) - * @ic: IGNORE_CASE or CASE_SENSITIVE (ignored if @name not present) - * @val: attribute value to find (optional, resident attributes only) - * @val_len: attribute value length - * @ctx: search context with mft record and attribute to search from - * - * You should not need to call this function directly. Use ntfs_attr_lookup() - * instead. - * - * ntfs_attr_find() takes a search context @ctx as parameter and searches the - * mft record specified by @ctx->mrec, beginning at @ctx->attr, for an - * attribute of @type, optionally @name and @val. - * - * If the attribute is found, ntfs_attr_find() returns 0 and @ctx->attr will - * point to the found attribute. - * - * If the attribute is not found, ntfs_attr_find() returns -ENOENT and - * @ctx->attr will point to the attribute before which the attribute being - * searched for would need to be inserted if such an action were to be desired. - * - * On actual error, ntfs_attr_find() returns -EIO. In this case @ctx->attr is - * undefined and in particular do not rely on it not changing. - * - * If @ctx->is_first is 'true', the search begins with @ctx->attr itself. If it - * is 'false', the search begins after @ctx->attr. - * - * If @ic is IGNORE_CASE, the @name comparisson is not case sensitive and - * @ctx->ntfs_ino must be set to the ntfs inode to which the mft record - * @ctx->mrec belongs. This is so we can get at the ntfs volume and hence at - * the upcase table. If @ic is CASE_SENSITIVE, the comparison is case - * sensitive. When @name is present, @name_len is the @name length in Unicode - * characters. - * - * If @name is not present (NULL), we assume that the unnamed attribute is - * being searched for. - * - * Finally, the resident attribute value @val is looked for, if present. If - * @val is not present (NULL), @val_len is ignored. - * - * ntfs_attr_find() only searches the specified mft record and it ignores the - * presence of an attribute list attribute (unless it is the one being searched - * for, obviously). If you need to take attribute lists into consideration, - * use ntfs_attr_lookup() instead (see below). This also means that you cannot - * use ntfs_attr_find() to search for extent records of non-resident - * attributes, as extents with lowest_vcn != 0 are usually described by the - * attribute list attribute only. - Note that it is possible that the first - * extent is only in the attribute list while the last extent is in the base - * mft record, so do not rely on being able to find the first extent in the - * base mft record. - * - * Warning: Never use @val when looking for attribute types which can be - * non-resident as this most likely will result in a crash! - */ -static int ntfs_attr_find(const ATTR_TYPE type, const ntfschar *name, - const u32 name_len, const IGNORE_CASE_BOOL ic, - const u8 *val, const u32 val_len, ntfs_attr_search_ctx *ctx) -{ - ATTR_RECORD *a; - ntfs_volume *vol = ctx->ntfs_ino->vol; - ntfschar *upcase = vol->upcase; - u32 upcase_len = vol->upcase_len; - - /* - * Iterate over attributes in mft record starting at @ctx->attr, or the - * attribute following that, if @ctx->is_first is 'true'. - */ - if (ctx->is_first) { - a = ctx->attr; - ctx->is_first = false; - } else - a = (ATTR_RECORD*)((u8*)ctx->attr + - le32_to_cpu(ctx->attr->length)); - for (;; a = (ATTR_RECORD*)((u8*)a + le32_to_cpu(a->length))) { - u8 *mrec_end = (u8 *)ctx->mrec + - le32_to_cpu(ctx->mrec->bytes_allocated); - u8 *name_end; - - /* check whether ATTR_RECORD wrap */ - if ((u8 *)a < (u8 *)ctx->mrec) - break; - - /* check whether Attribute Record Header is within bounds */ - if ((u8 *)a > mrec_end || - (u8 *)a + sizeof(ATTR_RECORD) > mrec_end) - break; - - /* check whether ATTR_RECORD's name is within bounds */ - name_end = (u8 *)a + le16_to_cpu(a->name_offset) + - a->name_length * sizeof(ntfschar); - if (name_end > mrec_end) - break; - - ctx->attr = a; - if (unlikely(le32_to_cpu(a->type) > le32_to_cpu(type) || - a->type == AT_END)) - return -ENOENT; - if (unlikely(!a->length)) - break; - - /* check whether ATTR_RECORD's length wrap */ - if ((u8 *)a + le32_to_cpu(a->length) < (u8 *)a) - break; - /* check whether ATTR_RECORD's length is within bounds */ - if ((u8 *)a + le32_to_cpu(a->length) > mrec_end) - break; - - if (a->type != type) - continue; - /* - * If @name is present, compare the two names. If @name is - * missing, assume we want an unnamed attribute. - */ - if (!name) { - /* The search failed if the found attribute is named. */ - if (a->name_length) - return -ENOENT; - } else if (!ntfs_are_names_equal(name, name_len, - (ntfschar*)((u8*)a + le16_to_cpu(a->name_offset)), - a->name_length, ic, upcase, upcase_len)) { - register int rc; - - rc = ntfs_collate_names(name, name_len, - (ntfschar*)((u8*)a + - le16_to_cpu(a->name_offset)), - a->name_length, 1, IGNORE_CASE, - upcase, upcase_len); - /* - * If @name collates before a->name, there is no - * matching attribute. - */ - if (rc == -1) - return -ENOENT; - /* If the strings are not equal, continue search. */ - if (rc) - continue; - rc = ntfs_collate_names(name, name_len, - (ntfschar*)((u8*)a + - le16_to_cpu(a->name_offset)), - a->name_length, 1, CASE_SENSITIVE, - upcase, upcase_len); - if (rc == -1) - return -ENOENT; - if (rc) - continue; - } - /* - * The names match or @name not present and attribute is - * unnamed. If no @val specified, we have found the attribute - * and are done. - */ - if (!val) - return 0; - /* @val is present; compare values. */ - else { - register int rc; - - rc = memcmp(val, (u8*)a + le16_to_cpu( - a->data.resident.value_offset), - min_t(u32, val_len, le32_to_cpu( - a->data.resident.value_length))); - /* - * If @val collates before the current attribute's - * value, there is no matching attribute. - */ - if (!rc) { - register u32 avl; - - avl = le32_to_cpu( - a->data.resident.value_length); - if (val_len == avl) - return 0; - if (val_len < avl) - return -ENOENT; - } else if (rc < 0) - return -ENOENT; - } - } - ntfs_error(vol->sb, "Inode is corrupt. Run chkdsk."); - NVolSetErrors(vol); - return -EIO; -} - -/** - * load_attribute_list - load an attribute list into memory - * @vol: ntfs volume from which to read - * @runlist: runlist of the attribute list - * @al_start: destination buffer - * @size: size of the destination buffer in bytes - * @initialized_size: initialized size of the attribute list - * - * Walk the runlist @runlist and load all clusters from it copying them into - * the linear buffer @al. The maximum number of bytes copied to @al is @size - * bytes. Note, @size does not need to be a multiple of the cluster size. If - * @initialized_size is less than @size, the region in @al between - * @initialized_size and @size will be zeroed and not read from disk. - * - * Return 0 on success or -errno on error. - */ -int load_attribute_list(ntfs_volume *vol, runlist *runlist, u8 *al_start, - const s64 size, const s64 initialized_size) -{ - LCN lcn; - u8 *al = al_start; - u8 *al_end = al + initialized_size; - runlist_element *rl; - struct buffer_head *bh; - struct super_block *sb; - unsigned long block_size; - unsigned long block, max_block; - int err = 0; - unsigned char block_size_bits; - - ntfs_debug("Entering."); - if (!vol || !runlist || !al || size <= 0 || initialized_size < 0 || - initialized_size > size) - return -EINVAL; - if (!initialized_size) { - memset(al, 0, size); - return 0; - } - sb = vol->sb; - block_size = sb->s_blocksize; - block_size_bits = sb->s_blocksize_bits; - down_read(&runlist->lock); - rl = runlist->rl; - if (!rl) { - ntfs_error(sb, "Cannot read attribute list since runlist is " - "missing."); - goto err_out; - } - /* Read all clusters specified by the runlist one run at a time. */ - while (rl->length) { - lcn = ntfs_rl_vcn_to_lcn(rl, rl->vcn); - ntfs_debug("Reading vcn = 0x%llx, lcn = 0x%llx.", - (unsigned long long)rl->vcn, - (unsigned long long)lcn); - /* The attribute list cannot be sparse. */ - if (lcn < 0) { - ntfs_error(sb, "ntfs_rl_vcn_to_lcn() failed. Cannot " - "read attribute list."); - goto err_out; - } - block = lcn << vol->cluster_size_bits >> block_size_bits; - /* Read the run from device in chunks of block_size bytes. */ - max_block = block + (rl->length << vol->cluster_size_bits >> - block_size_bits); - ntfs_debug("max_block = 0x%lx.", max_block); - do { - ntfs_debug("Reading block = 0x%lx.", block); - bh = sb_bread(sb, block); - if (!bh) { - ntfs_error(sb, "sb_bread() failed. Cannot " - "read attribute list."); - goto err_out; - } - if (al + block_size >= al_end) - goto do_final; - memcpy(al, bh->b_data, block_size); - brelse(bh); - al += block_size; - } while (++block < max_block); - rl++; - } - if (initialized_size < size) { -initialize: - memset(al_start + initialized_size, 0, size - initialized_size); - } -done: - up_read(&runlist->lock); - return err; -do_final: - if (al < al_end) { - /* - * Partial block. - * - * Note: The attribute list can be smaller than its allocation - * by multiple clusters. This has been encountered by at least - * two people running Windows XP, thus we cannot do any - * truncation sanity checking here. (AIA) - */ - memcpy(al, bh->b_data, al_end - al); - brelse(bh); - if (initialized_size < size) - goto initialize; - goto done; - } - brelse(bh); - /* Real overflow! */ - ntfs_error(sb, "Attribute list buffer overflow. Read attribute list " - "is truncated."); -err_out: - err = -EIO; - goto done; -} - -/** - * ntfs_external_attr_find - find an attribute in the attribute list of an inode - * @type: attribute type to find - * @name: attribute name to find (optional, i.e. NULL means don't care) - * @name_len: attribute name length (only needed if @name present) - * @ic: IGNORE_CASE or CASE_SENSITIVE (ignored if @name not present) - * @lowest_vcn: lowest vcn to find (optional, non-resident attributes only) - * @val: attribute value to find (optional, resident attributes only) - * @val_len: attribute value length - * @ctx: search context with mft record and attribute to search from - * - * You should not need to call this function directly. Use ntfs_attr_lookup() - * instead. - * - * Find an attribute by searching the attribute list for the corresponding - * attribute list entry. Having found the entry, map the mft record if the - * attribute is in a different mft record/inode, ntfs_attr_find() the attribute - * in there and return it. - * - * On first search @ctx->ntfs_ino must be the base mft record and @ctx must - * have been obtained from a call to ntfs_attr_get_search_ctx(). On subsequent - * calls @ctx->ntfs_ino can be any extent inode, too (@ctx->base_ntfs_ino is - * then the base inode). - * - * After finishing with the attribute/mft record you need to call - * ntfs_attr_put_search_ctx() to cleanup the search context (unmapping any - * mapped inodes, etc). - * - * If the attribute is found, ntfs_external_attr_find() returns 0 and - * @ctx->attr will point to the found attribute. @ctx->mrec will point to the - * mft record in which @ctx->attr is located and @ctx->al_entry will point to - * the attribute list entry for the attribute. - * - * If the attribute is not found, ntfs_external_attr_find() returns -ENOENT and - * @ctx->attr will point to the attribute in the base mft record before which - * the attribute being searched for would need to be inserted if such an action - * were to be desired. @ctx->mrec will point to the mft record in which - * @ctx->attr is located and @ctx->al_entry will point to the attribute list - * entry of the attribute before which the attribute being searched for would - * need to be inserted if such an action were to be desired. - * - * Thus to insert the not found attribute, one wants to add the attribute to - * @ctx->mrec (the base mft record) and if there is not enough space, the - * attribute should be placed in a newly allocated extent mft record. The - * attribute list entry for the inserted attribute should be inserted in the - * attribute list attribute at @ctx->al_entry. - * - * On actual error, ntfs_external_attr_find() returns -EIO. In this case - * @ctx->attr is undefined and in particular do not rely on it not changing. - */ -static int ntfs_external_attr_find(const ATTR_TYPE type, - const ntfschar *name, const u32 name_len, - const IGNORE_CASE_BOOL ic, const VCN lowest_vcn, - const u8 *val, const u32 val_len, ntfs_attr_search_ctx *ctx) -{ - ntfs_inode *base_ni, *ni; - ntfs_volume *vol; - ATTR_LIST_ENTRY *al_entry, *next_al_entry; - u8 *al_start, *al_end; - ATTR_RECORD *a; - ntfschar *al_name; - u32 al_name_len; - int err = 0; - static const char *es = " Unmount and run chkdsk."; - - ni = ctx->ntfs_ino; - base_ni = ctx->base_ntfs_ino; - ntfs_debug("Entering for inode 0x%lx, type 0x%x.", ni->mft_no, type); - if (!base_ni) { - /* First call happens with the base mft record. */ - base_ni = ctx->base_ntfs_ino = ctx->ntfs_ino; - ctx->base_mrec = ctx->mrec; - } - if (ni == base_ni) - ctx->base_attr = ctx->attr; - if (type == AT_END) - goto not_found; - vol = base_ni->vol; - al_start = base_ni->attr_list; - al_end = al_start + base_ni->attr_list_size; - if (!ctx->al_entry) - ctx->al_entry = (ATTR_LIST_ENTRY*)al_start; - /* - * Iterate over entries in attribute list starting at @ctx->al_entry, - * or the entry following that, if @ctx->is_first is 'true'. - */ - if (ctx->is_first) { - al_entry = ctx->al_entry; - ctx->is_first = false; - } else - al_entry = (ATTR_LIST_ENTRY*)((u8*)ctx->al_entry + - le16_to_cpu(ctx->al_entry->length)); - for (;; al_entry = next_al_entry) { - /* Out of bounds check. */ - if ((u8*)al_entry < base_ni->attr_list || - (u8*)al_entry > al_end) - break; /* Inode is corrupt. */ - ctx->al_entry = al_entry; - /* Catch the end of the attribute list. */ - if ((u8*)al_entry == al_end) - goto not_found; - if (!al_entry->length) - break; - if ((u8*)al_entry + 6 > al_end || (u8*)al_entry + - le16_to_cpu(al_entry->length) > al_end) - break; - next_al_entry = (ATTR_LIST_ENTRY*)((u8*)al_entry + - le16_to_cpu(al_entry->length)); - if (le32_to_cpu(al_entry->type) > le32_to_cpu(type)) - goto not_found; - if (type != al_entry->type) - continue; - /* - * If @name is present, compare the two names. If @name is - * missing, assume we want an unnamed attribute. - */ - al_name_len = al_entry->name_length; - al_name = (ntfschar*)((u8*)al_entry + al_entry->name_offset); - if (!name) { - if (al_name_len) - goto not_found; - } else if (!ntfs_are_names_equal(al_name, al_name_len, name, - name_len, ic, vol->upcase, vol->upcase_len)) { - register int rc; - - rc = ntfs_collate_names(name, name_len, al_name, - al_name_len, 1, IGNORE_CASE, - vol->upcase, vol->upcase_len); - /* - * If @name collates before al_name, there is no - * matching attribute. - */ - if (rc == -1) - goto not_found; - /* If the strings are not equal, continue search. */ - if (rc) - continue; - /* - * FIXME: Reverse engineering showed 0, IGNORE_CASE but - * that is inconsistent with ntfs_attr_find(). The - * subsequent rc checks were also different. Perhaps I - * made a mistake in one of the two. Need to recheck - * which is correct or at least see what is going on... - * (AIA) - */ - rc = ntfs_collate_names(name, name_len, al_name, - al_name_len, 1, CASE_SENSITIVE, - vol->upcase, vol->upcase_len); - if (rc == -1) - goto not_found; - if (rc) - continue; - } - /* - * The names match or @name not present and attribute is - * unnamed. Now check @lowest_vcn. Continue search if the - * next attribute list entry still fits @lowest_vcn. Otherwise - * we have reached the right one or the search has failed. - */ - if (lowest_vcn && (u8*)next_al_entry >= al_start && - (u8*)next_al_entry + 6 < al_end && - (u8*)next_al_entry + le16_to_cpu( - next_al_entry->length) <= al_end && - sle64_to_cpu(next_al_entry->lowest_vcn) <= - lowest_vcn && - next_al_entry->type == al_entry->type && - next_al_entry->name_length == al_name_len && - ntfs_are_names_equal((ntfschar*)((u8*) - next_al_entry + - next_al_entry->name_offset), - next_al_entry->name_length, - al_name, al_name_len, CASE_SENSITIVE, - vol->upcase, vol->upcase_len)) - continue; - if (MREF_LE(al_entry->mft_reference) == ni->mft_no) { - if (MSEQNO_LE(al_entry->mft_reference) != ni->seq_no) { - ntfs_error(vol->sb, "Found stale mft " - "reference in attribute list " - "of base inode 0x%lx.%s", - base_ni->mft_no, es); - err = -EIO; - break; - } - } else { /* Mft references do not match. */ - /* If there is a mapped record unmap it first. */ - if (ni != base_ni) - unmap_extent_mft_record(ni); - /* Do we want the base record back? */ - if (MREF_LE(al_entry->mft_reference) == - base_ni->mft_no) { - ni = ctx->ntfs_ino = base_ni; - ctx->mrec = ctx->base_mrec; - } else { - /* We want an extent record. */ - ctx->mrec = map_extent_mft_record(base_ni, - le64_to_cpu( - al_entry->mft_reference), &ni); - if (IS_ERR(ctx->mrec)) { - ntfs_error(vol->sb, "Failed to map " - "extent mft record " - "0x%lx of base inode " - "0x%lx.%s", - MREF_LE(al_entry-> - mft_reference), - base_ni->mft_no, es); - err = PTR_ERR(ctx->mrec); - if (err == -ENOENT) - err = -EIO; - /* Cause @ctx to be sanitized below. */ - ni = NULL; - break; - } - ctx->ntfs_ino = ni; - } - ctx->attr = (ATTR_RECORD*)((u8*)ctx->mrec + - le16_to_cpu(ctx->mrec->attrs_offset)); - } - /* - * ctx->vfs_ino, ctx->mrec, and ctx->attr now point to the - * mft record containing the attribute represented by the - * current al_entry. - */ - /* - * We could call into ntfs_attr_find() to find the right - * attribute in this mft record but this would be less - * efficient and not quite accurate as ntfs_attr_find() ignores - * the attribute instance numbers for example which become - * important when one plays with attribute lists. Also, - * because a proper match has been found in the attribute list - * entry above, the comparison can now be optimized. So it is - * worth re-implementing a simplified ntfs_attr_find() here. - */ - a = ctx->attr; - /* - * Use a manual loop so we can still use break and continue - * with the same meanings as above. - */ -do_next_attr_loop: - if ((u8*)a < (u8*)ctx->mrec || (u8*)a > (u8*)ctx->mrec + - le32_to_cpu(ctx->mrec->bytes_allocated)) - break; - if (a->type == AT_END) - break; - if (!a->length) - break; - if (al_entry->instance != a->instance) - goto do_next_attr; - /* - * If the type and/or the name are mismatched between the - * attribute list entry and the attribute record, there is - * corruption so we break and return error EIO. - */ - if (al_entry->type != a->type) - break; - if (!ntfs_are_names_equal((ntfschar*)((u8*)a + - le16_to_cpu(a->name_offset)), a->name_length, - al_name, al_name_len, CASE_SENSITIVE, - vol->upcase, vol->upcase_len)) - break; - ctx->attr = a; - /* - * If no @val specified or @val specified and it matches, we - * have found it! - */ - if (!val || (!a->non_resident && le32_to_cpu( - a->data.resident.value_length) == val_len && - !memcmp((u8*)a + - le16_to_cpu(a->data.resident.value_offset), - val, val_len))) { - ntfs_debug("Done, found."); - return 0; - } -do_next_attr: - /* Proceed to the next attribute in the current mft record. */ - a = (ATTR_RECORD*)((u8*)a + le32_to_cpu(a->length)); - goto do_next_attr_loop; - } - if (!err) { - ntfs_error(vol->sb, "Base inode 0x%lx contains corrupt " - "attribute list attribute.%s", base_ni->mft_no, - es); - err = -EIO; - } - if (ni != base_ni) { - if (ni) - unmap_extent_mft_record(ni); - ctx->ntfs_ino = base_ni; - ctx->mrec = ctx->base_mrec; - ctx->attr = ctx->base_attr; - } - if (err != -ENOMEM) - NVolSetErrors(vol); - return err; -not_found: - /* - * If we were looking for AT_END, we reset the search context @ctx and - * use ntfs_attr_find() to seek to the end of the base mft record. - */ - if (type == AT_END) { - ntfs_attr_reinit_search_ctx(ctx); - return ntfs_attr_find(AT_END, name, name_len, ic, val, val_len, - ctx); - } - /* - * The attribute was not found. Before we return, we want to ensure - * @ctx->mrec and @ctx->attr indicate the position at which the - * attribute should be inserted in the base mft record. Since we also - * want to preserve @ctx->al_entry we cannot reinitialize the search - * context using ntfs_attr_reinit_search_ctx() as this would set - * @ctx->al_entry to NULL. Thus we do the necessary bits manually (see - * ntfs_attr_init_search_ctx() below). Note, we _only_ preserve - * @ctx->al_entry as the remaining fields (base_*) are identical to - * their non base_ counterparts and we cannot set @ctx->base_attr - * correctly yet as we do not know what @ctx->attr will be set to by - * the call to ntfs_attr_find() below. - */ - if (ni != base_ni) - unmap_extent_mft_record(ni); - ctx->mrec = ctx->base_mrec; - ctx->attr = (ATTR_RECORD*)((u8*)ctx->mrec + - le16_to_cpu(ctx->mrec->attrs_offset)); - ctx->is_first = true; - ctx->ntfs_ino = base_ni; - ctx->base_ntfs_ino = NULL; - ctx->base_mrec = NULL; - ctx->base_attr = NULL; - /* - * In case there are multiple matches in the base mft record, need to - * keep enumerating until we get an attribute not found response (or - * another error), otherwise we would keep returning the same attribute - * over and over again and all programs using us for enumeration would - * lock up in a tight loop. - */ - do { - err = ntfs_attr_find(type, name, name_len, ic, val, val_len, - ctx); - } while (!err); - ntfs_debug("Done, not found."); - return err; -} - -/** - * ntfs_attr_lookup - find an attribute in an ntfs inode - * @type: attribute type to find - * @name: attribute name to find (optional, i.e. NULL means don't care) - * @name_len: attribute name length (only needed if @name present) - * @ic: IGNORE_CASE or CASE_SENSITIVE (ignored if @name not present) - * @lowest_vcn: lowest vcn to find (optional, non-resident attributes only) - * @val: attribute value to find (optional, resident attributes only) - * @val_len: attribute value length - * @ctx: search context with mft record and attribute to search from - * - * Find an attribute in an ntfs inode. On first search @ctx->ntfs_ino must - * be the base mft record and @ctx must have been obtained from a call to - * ntfs_attr_get_search_ctx(). - * - * This function transparently handles attribute lists and @ctx is used to - * continue searches where they were left off at. - * - * After finishing with the attribute/mft record you need to call - * ntfs_attr_put_search_ctx() to cleanup the search context (unmapping any - * mapped inodes, etc). - * - * Return 0 if the search was successful and -errno if not. - * - * When 0, @ctx->attr is the found attribute and it is in mft record - * @ctx->mrec. If an attribute list attribute is present, @ctx->al_entry is - * the attribute list entry of the found attribute. - * - * When -ENOENT, @ctx->attr is the attribute which collates just after the - * attribute being searched for, i.e. if one wants to add the attribute to the - * mft record this is the correct place to insert it into. If an attribute - * list attribute is present, @ctx->al_entry is the attribute list entry which - * collates just after the attribute list entry of the attribute being searched - * for, i.e. if one wants to add the attribute to the mft record this is the - * correct place to insert its attribute list entry into. - * - * When -errno != -ENOENT, an error occurred during the lookup. @ctx->attr is - * then undefined and in particular you should not rely on it not changing. - */ -int ntfs_attr_lookup(const ATTR_TYPE type, const ntfschar *name, - const u32 name_len, const IGNORE_CASE_BOOL ic, - const VCN lowest_vcn, const u8 *val, const u32 val_len, - ntfs_attr_search_ctx *ctx) -{ - ntfs_inode *base_ni; - - ntfs_debug("Entering."); - BUG_ON(IS_ERR(ctx->mrec)); - if (ctx->base_ntfs_ino) - base_ni = ctx->base_ntfs_ino; - else - base_ni = ctx->ntfs_ino; - /* Sanity check, just for debugging really. */ - BUG_ON(!base_ni); - if (!NInoAttrList(base_ni) || type == AT_ATTRIBUTE_LIST) - return ntfs_attr_find(type, name, name_len, ic, val, val_len, - ctx); - return ntfs_external_attr_find(type, name, name_len, ic, lowest_vcn, - val, val_len, ctx); -} - -/** - * ntfs_attr_init_search_ctx - initialize an attribute search context - * @ctx: attribute search context to initialize - * @ni: ntfs inode with which to initialize the search context - * @mrec: mft record with which to initialize the search context - * - * Initialize the attribute search context @ctx with @ni and @mrec. - */ -static inline void ntfs_attr_init_search_ctx(ntfs_attr_search_ctx *ctx, - ntfs_inode *ni, MFT_RECORD *mrec) -{ - *ctx = (ntfs_attr_search_ctx) { - .mrec = mrec, - /* Sanity checks are performed elsewhere. */ - .attr = (ATTR_RECORD*)((u8*)mrec + - le16_to_cpu(mrec->attrs_offset)), - .is_first = true, - .ntfs_ino = ni, - }; -} - -/** - * ntfs_attr_reinit_search_ctx - reinitialize an attribute search context - * @ctx: attribute search context to reinitialize - * - * Reinitialize the attribute search context @ctx, unmapping an associated - * extent mft record if present, and initialize the search context again. - * - * This is used when a search for a new attribute is being started to reset - * the search context to the beginning. - */ -void ntfs_attr_reinit_search_ctx(ntfs_attr_search_ctx *ctx) -{ - if (likely(!ctx->base_ntfs_ino)) { - /* No attribute list. */ - ctx->is_first = true; - /* Sanity checks are performed elsewhere. */ - ctx->attr = (ATTR_RECORD*)((u8*)ctx->mrec + - le16_to_cpu(ctx->mrec->attrs_offset)); - /* - * This needs resetting due to ntfs_external_attr_find() which - * can leave it set despite having zeroed ctx->base_ntfs_ino. - */ - ctx->al_entry = NULL; - return; - } /* Attribute list. */ - if (ctx->ntfs_ino != ctx->base_ntfs_ino) - unmap_extent_mft_record(ctx->ntfs_ino); - ntfs_attr_init_search_ctx(ctx, ctx->base_ntfs_ino, ctx->base_mrec); - return; -} - -/** - * ntfs_attr_get_search_ctx - allocate/initialize a new attribute search context - * @ni: ntfs inode with which to initialize the search context - * @mrec: mft record with which to initialize the search context - * - * Allocate a new attribute search context, initialize it with @ni and @mrec, - * and return it. Return NULL if allocation failed. - */ -ntfs_attr_search_ctx *ntfs_attr_get_search_ctx(ntfs_inode *ni, MFT_RECORD *mrec) -{ - ntfs_attr_search_ctx *ctx; - - ctx = kmem_cache_alloc(ntfs_attr_ctx_cache, GFP_NOFS); - if (ctx) - ntfs_attr_init_search_ctx(ctx, ni, mrec); - return ctx; -} - -/** - * ntfs_attr_put_search_ctx - release an attribute search context - * @ctx: attribute search context to free - * - * Release the attribute search context @ctx, unmapping an associated extent - * mft record if present. - */ -void ntfs_attr_put_search_ctx(ntfs_attr_search_ctx *ctx) -{ - if (ctx->base_ntfs_ino && ctx->ntfs_ino != ctx->base_ntfs_ino) - unmap_extent_mft_record(ctx->ntfs_ino); - kmem_cache_free(ntfs_attr_ctx_cache, ctx); - return; -} - -#ifdef NTFS_RW - -/** - * ntfs_attr_find_in_attrdef - find an attribute in the $AttrDef system file - * @vol: ntfs volume to which the attribute belongs - * @type: attribute type which to find - * - * Search for the attribute definition record corresponding to the attribute - * @type in the $AttrDef system file. - * - * Return the attribute type definition record if found and NULL if not found. - */ -static ATTR_DEF *ntfs_attr_find_in_attrdef(const ntfs_volume *vol, - const ATTR_TYPE type) -{ - ATTR_DEF *ad; - - BUG_ON(!vol->attrdef); - BUG_ON(!type); - for (ad = vol->attrdef; (u8*)ad - (u8*)vol->attrdef < - vol->attrdef_size && ad->type; ++ad) { - /* We have not found it yet, carry on searching. */ - if (likely(le32_to_cpu(ad->type) < le32_to_cpu(type))) - continue; - /* We found the attribute; return it. */ - if (likely(ad->type == type)) - return ad; - /* We have gone too far already. No point in continuing. */ - break; - } - /* Attribute not found. */ - ntfs_debug("Attribute type 0x%x not found in $AttrDef.", - le32_to_cpu(type)); - return NULL; -} - -/** - * ntfs_attr_size_bounds_check - check a size of an attribute type for validity - * @vol: ntfs volume to which the attribute belongs - * @type: attribute type which to check - * @size: size which to check - * - * Check whether the @size in bytes is valid for an attribute of @type on the - * ntfs volume @vol. This information is obtained from $AttrDef system file. - * - * Return 0 if valid, -ERANGE if not valid, or -ENOENT if the attribute is not - * listed in $AttrDef. - */ -int ntfs_attr_size_bounds_check(const ntfs_volume *vol, const ATTR_TYPE type, - const s64 size) -{ - ATTR_DEF *ad; - - BUG_ON(size < 0); - /* - * $ATTRIBUTE_LIST has a maximum size of 256kiB, but this is not - * listed in $AttrDef. - */ - if (unlikely(type == AT_ATTRIBUTE_LIST && size > 256 * 1024)) - return -ERANGE; - /* Get the $AttrDef entry for the attribute @type. */ - ad = ntfs_attr_find_in_attrdef(vol, type); - if (unlikely(!ad)) - return -ENOENT; - /* Do the bounds check. */ - if (((sle64_to_cpu(ad->min_size) > 0) && - size < sle64_to_cpu(ad->min_size)) || - ((sle64_to_cpu(ad->max_size) > 0) && size > - sle64_to_cpu(ad->max_size))) - return -ERANGE; - return 0; -} - -/** - * ntfs_attr_can_be_non_resident - check if an attribute can be non-resident - * @vol: ntfs volume to which the attribute belongs - * @type: attribute type which to check - * - * Check whether the attribute of @type on the ntfs volume @vol is allowed to - * be non-resident. This information is obtained from $AttrDef system file. - * - * Return 0 if the attribute is allowed to be non-resident, -EPERM if not, and - * -ENOENT if the attribute is not listed in $AttrDef. - */ -int ntfs_attr_can_be_non_resident(const ntfs_volume *vol, const ATTR_TYPE type) -{ - ATTR_DEF *ad; - - /* Find the attribute definition record in $AttrDef. */ - ad = ntfs_attr_find_in_attrdef(vol, type); - if (unlikely(!ad)) - return -ENOENT; - /* Check the flags and return the result. */ - if (ad->flags & ATTR_DEF_RESIDENT) - return -EPERM; - return 0; -} - -/** - * ntfs_attr_can_be_resident - check if an attribute can be resident - * @vol: ntfs volume to which the attribute belongs - * @type: attribute type which to check - * - * Check whether the attribute of @type on the ntfs volume @vol is allowed to - * be resident. This information is derived from our ntfs knowledge and may - * not be completely accurate, especially when user defined attributes are - * present. Basically we allow everything to be resident except for index - * allocation and $EA attributes. - * - * Return 0 if the attribute is allowed to be non-resident and -EPERM if not. - * - * Warning: In the system file $MFT the attribute $Bitmap must be non-resident - * otherwise windows will not boot (blue screen of death)! We cannot - * check for this here as we do not know which inode's $Bitmap is - * being asked about so the caller needs to special case this. - */ -int ntfs_attr_can_be_resident(const ntfs_volume *vol, const ATTR_TYPE type) -{ - if (type == AT_INDEX_ALLOCATION) - return -EPERM; - return 0; -} - -/** - * ntfs_attr_record_resize - resize an attribute record - * @m: mft record containing attribute record - * @a: attribute record to resize - * @new_size: new size in bytes to which to resize the attribute record @a - * - * Resize the attribute record @a, i.e. the resident part of the attribute, in - * the mft record @m to @new_size bytes. - * - * Return 0 on success and -errno on error. The following error codes are - * defined: - * -ENOSPC - Not enough space in the mft record @m to perform the resize. - * - * Note: On error, no modifications have been performed whatsoever. - * - * Warning: If you make a record smaller without having copied all the data you - * are interested in the data may be overwritten. - */ -int ntfs_attr_record_resize(MFT_RECORD *m, ATTR_RECORD *a, u32 new_size) -{ - ntfs_debug("Entering for new_size %u.", new_size); - /* Align to 8 bytes if it is not already done. */ - if (new_size & 7) - new_size = (new_size + 7) & ~7; - /* If the actual attribute length has changed, move things around. */ - if (new_size != le32_to_cpu(a->length)) { - u32 new_muse = le32_to_cpu(m->bytes_in_use) - - le32_to_cpu(a->length) + new_size; - /* Not enough space in this mft record. */ - if (new_muse > le32_to_cpu(m->bytes_allocated)) - return -ENOSPC; - /* Move attributes following @a to their new location. */ - memmove((u8*)a + new_size, (u8*)a + le32_to_cpu(a->length), - le32_to_cpu(m->bytes_in_use) - ((u8*)a - - (u8*)m) - le32_to_cpu(a->length)); - /* Adjust @m to reflect the change in used space. */ - m->bytes_in_use = cpu_to_le32(new_muse); - /* Adjust @a to reflect the new size. */ - if (new_size >= offsetof(ATTR_REC, length) + sizeof(a->length)) - a->length = cpu_to_le32(new_size); - } - return 0; -} - -/** - * ntfs_resident_attr_value_resize - resize the value of a resident attribute - * @m: mft record containing attribute record - * @a: attribute record whose value to resize - * @new_size: new size in bytes to which to resize the attribute value of @a - * - * Resize the value of the attribute @a in the mft record @m to @new_size bytes. - * If the value is made bigger, the newly allocated space is cleared. - * - * Return 0 on success and -errno on error. The following error codes are - * defined: - * -ENOSPC - Not enough space in the mft record @m to perform the resize. - * - * Note: On error, no modifications have been performed whatsoever. - * - * Warning: If you make a record smaller without having copied all the data you - * are interested in the data may be overwritten. - */ -int ntfs_resident_attr_value_resize(MFT_RECORD *m, ATTR_RECORD *a, - const u32 new_size) -{ - u32 old_size; - - /* Resize the resident part of the attribute record. */ - if (ntfs_attr_record_resize(m, a, - le16_to_cpu(a->data.resident.value_offset) + new_size)) - return -ENOSPC; - /* - * The resize succeeded! If we made the attribute value bigger, clear - * the area between the old size and @new_size. - */ - old_size = le32_to_cpu(a->data.resident.value_length); - if (new_size > old_size) - memset((u8*)a + le16_to_cpu(a->data.resident.value_offset) + - old_size, 0, new_size - old_size); - /* Finally update the length of the attribute value. */ - a->data.resident.value_length = cpu_to_le32(new_size); - return 0; -} - -/** - * ntfs_attr_make_non_resident - convert a resident to a non-resident attribute - * @ni: ntfs inode describing the attribute to convert - * @data_size: size of the resident data to copy to the non-resident attribute - * - * Convert the resident ntfs attribute described by the ntfs inode @ni to a - * non-resident one. - * - * @data_size must be equal to the attribute value size. This is needed since - * we need to know the size before we can map the mft record and our callers - * always know it. The reason we cannot simply read the size from the vfs - * inode i_size is that this is not necessarily uptodate. This happens when - * ntfs_attr_make_non_resident() is called in the ->truncate call path(s). - * - * Return 0 on success and -errno on error. The following error return codes - * are defined: - * -EPERM - The attribute is not allowed to be non-resident. - * -ENOMEM - Not enough memory. - * -ENOSPC - Not enough disk space. - * -EINVAL - Attribute not defined on the volume. - * -EIO - I/o error or other error. - * Note that -ENOSPC is also returned in the case that there is not enough - * space in the mft record to do the conversion. This can happen when the mft - * record is already very full. The caller is responsible for trying to make - * space in the mft record and trying again. FIXME: Do we need a separate - * error return code for this kind of -ENOSPC or is it always worth trying - * again in case the attribute may then fit in a resident state so no need to - * make it non-resident at all? Ho-hum... (AIA) - * - * NOTE to self: No changes in the attribute list are required to move from - * a resident to a non-resident attribute. - * - * Locking: - The caller must hold i_mutex on the inode. - */ -int ntfs_attr_make_non_resident(ntfs_inode *ni, const u32 data_size) -{ - s64 new_size; - struct inode *vi = VFS_I(ni); - ntfs_volume *vol = ni->vol; - ntfs_inode *base_ni; - MFT_RECORD *m; - ATTR_RECORD *a; - ntfs_attr_search_ctx *ctx; - struct page *page; - runlist_element *rl; - u8 *kaddr; - unsigned long flags; - int mp_size, mp_ofs, name_ofs, arec_size, err, err2; - u32 attr_size; - u8 old_res_attr_flags; - - /* Check that the attribute is allowed to be non-resident. */ - err = ntfs_attr_can_be_non_resident(vol, ni->type); - if (unlikely(err)) { - if (err == -EPERM) - ntfs_debug("Attribute is not allowed to be " - "non-resident."); - else - ntfs_debug("Attribute not defined on the NTFS " - "volume!"); - return err; - } - /* - * FIXME: Compressed and encrypted attributes are not supported when - * writing and we should never have gotten here for them. - */ - BUG_ON(NInoCompressed(ni)); - BUG_ON(NInoEncrypted(ni)); - /* - * The size needs to be aligned to a cluster boundary for allocation - * purposes. - */ - new_size = (data_size + vol->cluster_size - 1) & - ~(vol->cluster_size - 1); - if (new_size > 0) { - /* - * Will need the page later and since the page lock nests - * outside all ntfs locks, we need to get the page now. - */ - page = find_or_create_page(vi->i_mapping, 0, - mapping_gfp_mask(vi->i_mapping)); - if (unlikely(!page)) - return -ENOMEM; - /* Start by allocating clusters to hold the attribute value. */ - rl = ntfs_cluster_alloc(vol, 0, new_size >> - vol->cluster_size_bits, -1, DATA_ZONE, true); - if (IS_ERR(rl)) { - err = PTR_ERR(rl); - ntfs_debug("Failed to allocate cluster%s, error code " - "%i.", (new_size >> - vol->cluster_size_bits) > 1 ? "s" : "", - err); - goto page_err_out; - } - } else { - rl = NULL; - page = NULL; - } - /* Determine the size of the mapping pairs array. */ - mp_size = ntfs_get_size_for_mapping_pairs(vol, rl, 0, -1); - if (unlikely(mp_size < 0)) { - err = mp_size; - ntfs_debug("Failed to get size for mapping pairs array, error " - "code %i.", err); - goto rl_err_out; - } - down_write(&ni->runlist.lock); - if (!NInoAttr(ni)) - base_ni = ni; - else - base_ni = ni->ext.base_ntfs_ino; - m = map_mft_record(base_ni); - if (IS_ERR(m)) { - err = PTR_ERR(m); - m = NULL; - ctx = NULL; - goto err_out; - } - ctx = ntfs_attr_get_search_ctx(base_ni, m); - if (unlikely(!ctx)) { - err = -ENOMEM; - goto err_out; - } - err = ntfs_attr_lookup(ni->type, ni->name, ni->name_len, - CASE_SENSITIVE, 0, NULL, 0, ctx); - if (unlikely(err)) { - if (err == -ENOENT) - err = -EIO; - goto err_out; - } - m = ctx->mrec; - a = ctx->attr; - BUG_ON(NInoNonResident(ni)); - BUG_ON(a->non_resident); - /* - * Calculate new offsets for the name and the mapping pairs array. - */ - if (NInoSparse(ni) || NInoCompressed(ni)) - name_ofs = (offsetof(ATTR_REC, - data.non_resident.compressed_size) + - sizeof(a->data.non_resident.compressed_size) + - 7) & ~7; - else - name_ofs = (offsetof(ATTR_REC, - data.non_resident.compressed_size) + 7) & ~7; - mp_ofs = (name_ofs + a->name_length * sizeof(ntfschar) + 7) & ~7; - /* - * Determine the size of the resident part of the now non-resident - * attribute record. - */ - arec_size = (mp_ofs + mp_size + 7) & ~7; - /* - * If the page is not uptodate bring it uptodate by copying from the - * attribute value. - */ - attr_size = le32_to_cpu(a->data.resident.value_length); - BUG_ON(attr_size != data_size); - if (page && !PageUptodate(page)) { - kaddr = kmap_atomic(page); - memcpy(kaddr, (u8*)a + - le16_to_cpu(a->data.resident.value_offset), - attr_size); - memset(kaddr + attr_size, 0, PAGE_SIZE - attr_size); - kunmap_atomic(kaddr); - flush_dcache_page(page); - SetPageUptodate(page); - } - /* Backup the attribute flag. */ - old_res_attr_flags = a->data.resident.flags; - /* Resize the resident part of the attribute record. */ - err = ntfs_attr_record_resize(m, a, arec_size); - if (unlikely(err)) - goto err_out; - /* - * Convert the resident part of the attribute record to describe a - * non-resident attribute. - */ - a->non_resident = 1; - /* Move the attribute name if it exists and update the offset. */ - if (a->name_length) - memmove((u8*)a + name_ofs, (u8*)a + le16_to_cpu(a->name_offset), - a->name_length * sizeof(ntfschar)); - a->name_offset = cpu_to_le16(name_ofs); - /* Setup the fields specific to non-resident attributes. */ - a->data.non_resident.lowest_vcn = 0; - a->data.non_resident.highest_vcn = cpu_to_sle64((new_size - 1) >> - vol->cluster_size_bits); - a->data.non_resident.mapping_pairs_offset = cpu_to_le16(mp_ofs); - memset(&a->data.non_resident.reserved, 0, - sizeof(a->data.non_resident.reserved)); - a->data.non_resident.allocated_size = cpu_to_sle64(new_size); - a->data.non_resident.data_size = - a->data.non_resident.initialized_size = - cpu_to_sle64(attr_size); - if (NInoSparse(ni) || NInoCompressed(ni)) { - a->data.non_resident.compression_unit = 0; - if (NInoCompressed(ni) || vol->major_ver < 3) - a->data.non_resident.compression_unit = 4; - a->data.non_resident.compressed_size = - a->data.non_resident.allocated_size; - } else - a->data.non_resident.compression_unit = 0; - /* Generate the mapping pairs array into the attribute record. */ - err = ntfs_mapping_pairs_build(vol, (u8*)a + mp_ofs, - arec_size - mp_ofs, rl, 0, -1, NULL); - if (unlikely(err)) { - ntfs_debug("Failed to build mapping pairs, error code %i.", - err); - goto undo_err_out; - } - /* Setup the in-memory attribute structure to be non-resident. */ - ni->runlist.rl = rl; - write_lock_irqsave(&ni->size_lock, flags); - ni->allocated_size = new_size; - if (NInoSparse(ni) || NInoCompressed(ni)) { - ni->itype.compressed.size = ni->allocated_size; - if (a->data.non_resident.compression_unit) { - ni->itype.compressed.block_size = 1U << (a->data. - non_resident.compression_unit + - vol->cluster_size_bits); - ni->itype.compressed.block_size_bits = - ffs(ni->itype.compressed.block_size) - - 1; - ni->itype.compressed.block_clusters = 1U << - a->data.non_resident.compression_unit; - } else { - ni->itype.compressed.block_size = 0; - ni->itype.compressed.block_size_bits = 0; - ni->itype.compressed.block_clusters = 0; - } - vi->i_blocks = ni->itype.compressed.size >> 9; - } else - vi->i_blocks = ni->allocated_size >> 9; - write_unlock_irqrestore(&ni->size_lock, flags); - /* - * This needs to be last since the address space operations ->read_folio - * and ->writepage can run concurrently with us as they are not - * serialized on i_mutex. Note, we are not allowed to fail once we flip - * this switch, which is another reason to do this last. - */ - NInoSetNonResident(ni); - /* Mark the mft record dirty, so it gets written back. */ - flush_dcache_mft_record_page(ctx->ntfs_ino); - mark_mft_record_dirty(ctx->ntfs_ino); - ntfs_attr_put_search_ctx(ctx); - unmap_mft_record(base_ni); - up_write(&ni->runlist.lock); - if (page) { - set_page_dirty(page); - unlock_page(page); - put_page(page); - } - ntfs_debug("Done."); - return 0; -undo_err_out: - /* Convert the attribute back into a resident attribute. */ - a->non_resident = 0; - /* Move the attribute name if it exists and update the offset. */ - name_ofs = (offsetof(ATTR_RECORD, data.resident.reserved) + - sizeof(a->data.resident.reserved) + 7) & ~7; - if (a->name_length) - memmove((u8*)a + name_ofs, (u8*)a + le16_to_cpu(a->name_offset), - a->name_length * sizeof(ntfschar)); - mp_ofs = (name_ofs + a->name_length * sizeof(ntfschar) + 7) & ~7; - a->name_offset = cpu_to_le16(name_ofs); - arec_size = (mp_ofs + attr_size + 7) & ~7; - /* Resize the resident part of the attribute record. */ - err2 = ntfs_attr_record_resize(m, a, arec_size); - if (unlikely(err2)) { - /* - * This cannot happen (well if memory corruption is at work it - * could happen in theory), but deal with it as well as we can. - * If the old size is too small, truncate the attribute, - * otherwise simply give it a larger allocated size. - * FIXME: Should check whether chkdsk complains when the - * allocated size is much bigger than the resident value size. - */ - arec_size = le32_to_cpu(a->length); - if ((mp_ofs + attr_size) > arec_size) { - err2 = attr_size; - attr_size = arec_size - mp_ofs; - ntfs_error(vol->sb, "Failed to undo partial resident " - "to non-resident attribute " - "conversion. Truncating inode 0x%lx, " - "attribute type 0x%x from %i bytes to " - "%i bytes to maintain metadata " - "consistency. THIS MEANS YOU ARE " - "LOSING %i BYTES DATA FROM THIS %s.", - vi->i_ino, - (unsigned)le32_to_cpu(ni->type), - err2, attr_size, err2 - attr_size, - ((ni->type == AT_DATA) && - !ni->name_len) ? "FILE": "ATTRIBUTE"); - write_lock_irqsave(&ni->size_lock, flags); - ni->initialized_size = attr_size; - i_size_write(vi, attr_size); - write_unlock_irqrestore(&ni->size_lock, flags); - } - } - /* Setup the fields specific to resident attributes. */ - a->data.resident.value_length = cpu_to_le32(attr_size); - a->data.resident.value_offset = cpu_to_le16(mp_ofs); - a->data.resident.flags = old_res_attr_flags; - memset(&a->data.resident.reserved, 0, - sizeof(a->data.resident.reserved)); - /* Copy the data from the page back to the attribute value. */ - if (page) { - kaddr = kmap_atomic(page); - memcpy((u8*)a + mp_ofs, kaddr, attr_size); - kunmap_atomic(kaddr); - } - /* Setup the allocated size in the ntfs inode in case it changed. */ - write_lock_irqsave(&ni->size_lock, flags); - ni->allocated_size = arec_size - mp_ofs; - write_unlock_irqrestore(&ni->size_lock, flags); - /* Mark the mft record dirty, so it gets written back. */ - flush_dcache_mft_record_page(ctx->ntfs_ino); - mark_mft_record_dirty(ctx->ntfs_ino); -err_out: - if (ctx) - ntfs_attr_put_search_ctx(ctx); - if (m) - unmap_mft_record(base_ni); - ni->runlist.rl = NULL; - up_write(&ni->runlist.lock); -rl_err_out: - if (rl) { - if (ntfs_cluster_free_from_rl(vol, rl) < 0) { - ntfs_error(vol->sb, "Failed to release allocated " - "cluster(s) in error code path. Run " - "chkdsk to recover the lost " - "cluster(s)."); - NVolSetErrors(vol); - } - ntfs_free(rl); -page_err_out: - unlock_page(page); - put_page(page); - } - if (err == -EINVAL) - err = -EIO; - return err; -} - -/** - * ntfs_attr_extend_allocation - extend the allocated space of an attribute - * @ni: ntfs inode of the attribute whose allocation to extend - * @new_alloc_size: new size in bytes to which to extend the allocation to - * @new_data_size: new size in bytes to which to extend the data to - * @data_start: beginning of region which is required to be non-sparse - * - * Extend the allocated space of an attribute described by the ntfs inode @ni - * to @new_alloc_size bytes. If @data_start is -1, the whole extension may be - * implemented as a hole in the file (as long as both the volume and the ntfs - * inode @ni have sparse support enabled). If @data_start is >= 0, then the - * region between the old allocated size and @data_start - 1 may be made sparse - * but the regions between @data_start and @new_alloc_size must be backed by - * actual clusters. - * - * If @new_data_size is -1, it is ignored. If it is >= 0, then the data size - * of the attribute is extended to @new_data_size. Note that the i_size of the - * vfs inode is not updated. Only the data size in the base attribute record - * is updated. The caller has to update i_size separately if this is required. - * WARNING: It is a BUG() for @new_data_size to be smaller than the old data - * size as well as for @new_data_size to be greater than @new_alloc_size. - * - * For resident attributes this involves resizing the attribute record and if - * necessary moving it and/or other attributes into extent mft records and/or - * converting the attribute to a non-resident attribute which in turn involves - * extending the allocation of a non-resident attribute as described below. - * - * For non-resident attributes this involves allocating clusters in the data - * zone on the volume (except for regions that are being made sparse) and - * extending the run list to describe the allocated clusters as well as - * updating the mapping pairs array of the attribute. This in turn involves - * resizing the attribute record and if necessary moving it and/or other - * attributes into extent mft records and/or splitting the attribute record - * into multiple extent attribute records. - * - * Also, the attribute list attribute is updated if present and in some of the - * above cases (the ones where extent mft records/attributes come into play), - * an attribute list attribute is created if not already present. - * - * Return the new allocated size on success and -errno on error. In the case - * that an error is encountered but a partial extension at least up to - * @data_start (if present) is possible, the allocation is partially extended - * and this is returned. This means the caller must check the returned size to - * determine if the extension was partial. If @data_start is -1 then partial - * allocations are not performed. - * - * WARNING: Do not call ntfs_attr_extend_allocation() for $MFT/$DATA. - * - * Locking: This function takes the runlist lock of @ni for writing as well as - * locking the mft record of the base ntfs inode. These locks are maintained - * throughout execution of the function. These locks are required so that the - * attribute can be resized safely and so that it can for example be converted - * from resident to non-resident safely. - * - * TODO: At present attribute list attribute handling is not implemented. - * - * TODO: At present it is not safe to call this function for anything other - * than the $DATA attribute(s) of an uncompressed and unencrypted file. - */ -s64 ntfs_attr_extend_allocation(ntfs_inode *ni, s64 new_alloc_size, - const s64 new_data_size, const s64 data_start) -{ - VCN vcn; - s64 ll, allocated_size, start = data_start; - struct inode *vi = VFS_I(ni); - ntfs_volume *vol = ni->vol; - ntfs_inode *base_ni; - MFT_RECORD *m; - ATTR_RECORD *a; - ntfs_attr_search_ctx *ctx; - runlist_element *rl, *rl2; - unsigned long flags; - int err, mp_size; - u32 attr_len = 0; /* Silence stupid gcc warning. */ - bool mp_rebuilt; - -#ifdef DEBUG - read_lock_irqsave(&ni->size_lock, flags); - allocated_size = ni->allocated_size; - read_unlock_irqrestore(&ni->size_lock, flags); - ntfs_debug("Entering for i_ino 0x%lx, attribute type 0x%x, " - "old_allocated_size 0x%llx, " - "new_allocated_size 0x%llx, new_data_size 0x%llx, " - "data_start 0x%llx.", vi->i_ino, - (unsigned)le32_to_cpu(ni->type), - (unsigned long long)allocated_size, - (unsigned long long)new_alloc_size, - (unsigned long long)new_data_size, - (unsigned long long)start); -#endif -retry_extend: - /* - * For non-resident attributes, @start and @new_size need to be aligned - * to cluster boundaries for allocation purposes. - */ - if (NInoNonResident(ni)) { - if (start > 0) - start &= ~(s64)vol->cluster_size_mask; - new_alloc_size = (new_alloc_size + vol->cluster_size - 1) & - ~(s64)vol->cluster_size_mask; - } - BUG_ON(new_data_size >= 0 && new_data_size > new_alloc_size); - /* Check if new size is allowed in $AttrDef. */ - err = ntfs_attr_size_bounds_check(vol, ni->type, new_alloc_size); - if (unlikely(err)) { - /* Only emit errors when the write will fail completely. */ - read_lock_irqsave(&ni->size_lock, flags); - allocated_size = ni->allocated_size; - read_unlock_irqrestore(&ni->size_lock, flags); - if (start < 0 || start >= allocated_size) { - if (err == -ERANGE) { - ntfs_error(vol->sb, "Cannot extend allocation " - "of inode 0x%lx, attribute " - "type 0x%x, because the new " - "allocation would exceed the " - "maximum allowed size for " - "this attribute type.", - vi->i_ino, (unsigned) - le32_to_cpu(ni->type)); - } else { - ntfs_error(vol->sb, "Cannot extend allocation " - "of inode 0x%lx, attribute " - "type 0x%x, because this " - "attribute type is not " - "defined on the NTFS volume. " - "Possible corruption! You " - "should run chkdsk!", - vi->i_ino, (unsigned) - le32_to_cpu(ni->type)); - } - } - /* Translate error code to be POSIX conformant for write(2). */ - if (err == -ERANGE) - err = -EFBIG; - else - err = -EIO; - return err; - } - if (!NInoAttr(ni)) - base_ni = ni; - else - base_ni = ni->ext.base_ntfs_ino; - /* - * We will be modifying both the runlist (if non-resident) and the mft - * record so lock them both down. - */ - down_write(&ni->runlist.lock); - m = map_mft_record(base_ni); - if (IS_ERR(m)) { - err = PTR_ERR(m); - m = NULL; - ctx = NULL; - goto err_out; - } - ctx = ntfs_attr_get_search_ctx(base_ni, m); - if (unlikely(!ctx)) { - err = -ENOMEM; - goto err_out; - } - read_lock_irqsave(&ni->size_lock, flags); - allocated_size = ni->allocated_size; - read_unlock_irqrestore(&ni->size_lock, flags); - /* - * If non-resident, seek to the last extent. If resident, there is - * only one extent, so seek to that. - */ - vcn = NInoNonResident(ni) ? allocated_size >> vol->cluster_size_bits : - 0; - /* - * Abort if someone did the work whilst we waited for the locks. If we - * just converted the attribute from resident to non-resident it is - * likely that exactly this has happened already. We cannot quite - * abort if we need to update the data size. - */ - if (unlikely(new_alloc_size <= allocated_size)) { - ntfs_debug("Allocated size already exceeds requested size."); - new_alloc_size = allocated_size; - if (new_data_size < 0) - goto done; - /* - * We want the first attribute extent so that we can update the - * data size. - */ - vcn = 0; - } - err = ntfs_attr_lookup(ni->type, ni->name, ni->name_len, - CASE_SENSITIVE, vcn, NULL, 0, ctx); - if (unlikely(err)) { - if (err == -ENOENT) - err = -EIO; - goto err_out; - } - m = ctx->mrec; - a = ctx->attr; - /* Use goto to reduce indentation. */ - if (a->non_resident) - goto do_non_resident_extend; - BUG_ON(NInoNonResident(ni)); - /* The total length of the attribute value. */ - attr_len = le32_to_cpu(a->data.resident.value_length); - /* - * Extend the attribute record to be able to store the new attribute - * size. ntfs_attr_record_resize() will not do anything if the size is - * not changing. - */ - if (new_alloc_size < vol->mft_record_size && - !ntfs_attr_record_resize(m, a, - le16_to_cpu(a->data.resident.value_offset) + - new_alloc_size)) { - /* The resize succeeded! */ - write_lock_irqsave(&ni->size_lock, flags); - ni->allocated_size = le32_to_cpu(a->length) - - le16_to_cpu(a->data.resident.value_offset); - write_unlock_irqrestore(&ni->size_lock, flags); - if (new_data_size >= 0) { - BUG_ON(new_data_size < attr_len); - a->data.resident.value_length = - cpu_to_le32((u32)new_data_size); - } - goto flush_done; - } - /* - * We have to drop all the locks so we can call - * ntfs_attr_make_non_resident(). This could be optimised by try- - * locking the first page cache page and only if that fails dropping - * the locks, locking the page, and redoing all the locking and - * lookups. While this would be a huge optimisation, it is not worth - * it as this is definitely a slow code path. - */ - ntfs_attr_put_search_ctx(ctx); - unmap_mft_record(base_ni); - up_write(&ni->runlist.lock); - /* - * Not enough space in the mft record, try to make the attribute - * non-resident and if successful restart the extension process. - */ - err = ntfs_attr_make_non_resident(ni, attr_len); - if (likely(!err)) - goto retry_extend; - /* - * Could not make non-resident. If this is due to this not being - * permitted for this attribute type or there not being enough space, - * try to make other attributes non-resident. Otherwise fail. - */ - if (unlikely(err != -EPERM && err != -ENOSPC)) { - /* Only emit errors when the write will fail completely. */ - read_lock_irqsave(&ni->size_lock, flags); - allocated_size = ni->allocated_size; - read_unlock_irqrestore(&ni->size_lock, flags); - if (start < 0 || start >= allocated_size) - ntfs_error(vol->sb, "Cannot extend allocation of " - "inode 0x%lx, attribute type 0x%x, " - "because the conversion from resident " - "to non-resident attribute failed " - "with error code %i.", vi->i_ino, - (unsigned)le32_to_cpu(ni->type), err); - if (err != -ENOMEM) - err = -EIO; - goto conv_err_out; - } - /* TODO: Not implemented from here, abort. */ - read_lock_irqsave(&ni->size_lock, flags); - allocated_size = ni->allocated_size; - read_unlock_irqrestore(&ni->size_lock, flags); - if (start < 0 || start >= allocated_size) { - if (err == -ENOSPC) - ntfs_error(vol->sb, "Not enough space in the mft " - "record/on disk for the non-resident " - "attribute value. This case is not " - "implemented yet."); - else /* if (err == -EPERM) */ - ntfs_error(vol->sb, "This attribute type may not be " - "non-resident. This case is not " - "implemented yet."); - } - err = -EOPNOTSUPP; - goto conv_err_out; -#if 0 - // TODO: Attempt to make other attributes non-resident. - if (!err) - goto do_resident_extend; - /* - * Both the attribute list attribute and the standard information - * attribute must remain in the base inode. Thus, if this is one of - * these attributes, we have to try to move other attributes out into - * extent mft records instead. - */ - if (ni->type == AT_ATTRIBUTE_LIST || - ni->type == AT_STANDARD_INFORMATION) { - // TODO: Attempt to move other attributes into extent mft - // records. - err = -EOPNOTSUPP; - if (!err) - goto do_resident_extend; - goto err_out; - } - // TODO: Attempt to move this attribute to an extent mft record, but - // only if it is not already the only attribute in an mft record in - // which case there would be nothing to gain. - err = -EOPNOTSUPP; - if (!err) - goto do_resident_extend; - /* There is nothing we can do to make enough space. )-: */ - goto err_out; -#endif -do_non_resident_extend: - BUG_ON(!NInoNonResident(ni)); - if (new_alloc_size == allocated_size) { - BUG_ON(vcn); - goto alloc_done; - } - /* - * If the data starts after the end of the old allocation, this is a - * $DATA attribute and sparse attributes are enabled on the volume and - * for this inode, then create a sparse region between the old - * allocated size and the start of the data. Otherwise simply proceed - * with filling the whole space between the old allocated size and the - * new allocated size with clusters. - */ - if ((start >= 0 && start <= allocated_size) || ni->type != AT_DATA || - !NVolSparseEnabled(vol) || NInoSparseDisabled(ni)) - goto skip_sparse; - // TODO: This is not implemented yet. We just fill in with real - // clusters for now... - ntfs_debug("Inserting holes is not-implemented yet. Falling back to " - "allocating real clusters instead."); -skip_sparse: - rl = ni->runlist.rl; - if (likely(rl)) { - /* Seek to the end of the runlist. */ - while (rl->length) - rl++; - } - /* If this attribute extent is not mapped, map it now. */ - if (unlikely(!rl || rl->lcn == LCN_RL_NOT_MAPPED || - (rl->lcn == LCN_ENOENT && rl > ni->runlist.rl && - (rl-1)->lcn == LCN_RL_NOT_MAPPED))) { - if (!rl && !allocated_size) - goto first_alloc; - rl = ntfs_mapping_pairs_decompress(vol, a, ni->runlist.rl); - if (IS_ERR(rl)) { - err = PTR_ERR(rl); - if (start < 0 || start >= allocated_size) - ntfs_error(vol->sb, "Cannot extend allocation " - "of inode 0x%lx, attribute " - "type 0x%x, because the " - "mapping of a runlist " - "fragment failed with error " - "code %i.", vi->i_ino, - (unsigned)le32_to_cpu(ni->type), - err); - if (err != -ENOMEM) - err = -EIO; - goto err_out; - } - ni->runlist.rl = rl; - /* Seek to the end of the runlist. */ - while (rl->length) - rl++; - } - /* - * We now know the runlist of the last extent is mapped and @rl is at - * the end of the runlist. We want to begin allocating clusters - * starting at the last allocated cluster to reduce fragmentation. If - * there are no valid LCNs in the attribute we let the cluster - * allocator choose the starting cluster. - */ - /* If the last LCN is a hole or simillar seek back to last real LCN. */ - while (rl->lcn < 0 && rl > ni->runlist.rl) - rl--; -first_alloc: - // FIXME: Need to implement partial allocations so at least part of the - // write can be performed when start >= 0. (Needed for POSIX write(2) - // conformance.) - rl2 = ntfs_cluster_alloc(vol, allocated_size >> vol->cluster_size_bits, - (new_alloc_size - allocated_size) >> - vol->cluster_size_bits, (rl && (rl->lcn >= 0)) ? - rl->lcn + rl->length : -1, DATA_ZONE, true); - if (IS_ERR(rl2)) { - err = PTR_ERR(rl2); - if (start < 0 || start >= allocated_size) - ntfs_error(vol->sb, "Cannot extend allocation of " - "inode 0x%lx, attribute type 0x%x, " - "because the allocation of clusters " - "failed with error code %i.", vi->i_ino, - (unsigned)le32_to_cpu(ni->type), err); - if (err != -ENOMEM && err != -ENOSPC) - err = -EIO; - goto err_out; - } - rl = ntfs_runlists_merge(ni->runlist.rl, rl2); - if (IS_ERR(rl)) { - err = PTR_ERR(rl); - if (start < 0 || start >= allocated_size) - ntfs_error(vol->sb, "Cannot extend allocation of " - "inode 0x%lx, attribute type 0x%x, " - "because the runlist merge failed " - "with error code %i.", vi->i_ino, - (unsigned)le32_to_cpu(ni->type), err); - if (err != -ENOMEM) - err = -EIO; - if (ntfs_cluster_free_from_rl(vol, rl2)) { - ntfs_error(vol->sb, "Failed to release allocated " - "cluster(s) in error code path. Run " - "chkdsk to recover the lost " - "cluster(s)."); - NVolSetErrors(vol); - } - ntfs_free(rl2); - goto err_out; - } - ni->runlist.rl = rl; - ntfs_debug("Allocated 0x%llx clusters.", (long long)(new_alloc_size - - allocated_size) >> vol->cluster_size_bits); - /* Find the runlist element with which the attribute extent starts. */ - ll = sle64_to_cpu(a->data.non_resident.lowest_vcn); - rl2 = ntfs_rl_find_vcn_nolock(rl, ll); - BUG_ON(!rl2); - BUG_ON(!rl2->length); - BUG_ON(rl2->lcn < LCN_HOLE); - mp_rebuilt = false; - /* Get the size for the new mapping pairs array for this extent. */ - mp_size = ntfs_get_size_for_mapping_pairs(vol, rl2, ll, -1); - if (unlikely(mp_size <= 0)) { - err = mp_size; - if (start < 0 || start >= allocated_size) - ntfs_error(vol->sb, "Cannot extend allocation of " - "inode 0x%lx, attribute type 0x%x, " - "because determining the size for the " - "mapping pairs failed with error code " - "%i.", vi->i_ino, - (unsigned)le32_to_cpu(ni->type), err); - err = -EIO; - goto undo_alloc; - } - /* Extend the attribute record to fit the bigger mapping pairs array. */ - attr_len = le32_to_cpu(a->length); - err = ntfs_attr_record_resize(m, a, mp_size + - le16_to_cpu(a->data.non_resident.mapping_pairs_offset)); - if (unlikely(err)) { - BUG_ON(err != -ENOSPC); - // TODO: Deal with this by moving this extent to a new mft - // record or by starting a new extent in a new mft record, - // possibly by extending this extent partially and filling it - // and creating a new extent for the remainder, or by making - // other attributes non-resident and/or by moving other - // attributes out of this mft record. - if (start < 0 || start >= allocated_size) - ntfs_error(vol->sb, "Not enough space in the mft " - "record for the extended attribute " - "record. This case is not " - "implemented yet."); - err = -EOPNOTSUPP; - goto undo_alloc; - } - mp_rebuilt = true; - /* Generate the mapping pairs array directly into the attr record. */ - err = ntfs_mapping_pairs_build(vol, (u8*)a + - le16_to_cpu(a->data.non_resident.mapping_pairs_offset), - mp_size, rl2, ll, -1, NULL); - if (unlikely(err)) { - if (start < 0 || start >= allocated_size) - ntfs_error(vol->sb, "Cannot extend allocation of " - "inode 0x%lx, attribute type 0x%x, " - "because building the mapping pairs " - "failed with error code %i.", vi->i_ino, - (unsigned)le32_to_cpu(ni->type), err); - err = -EIO; - goto undo_alloc; - } - /* Update the highest_vcn. */ - a->data.non_resident.highest_vcn = cpu_to_sle64((new_alloc_size >> - vol->cluster_size_bits) - 1); - /* - * We now have extended the allocated size of the attribute. Reflect - * this in the ntfs_inode structure and the attribute record. - */ - if (a->data.non_resident.lowest_vcn) { - /* - * We are not in the first attribute extent, switch to it, but - * first ensure the changes will make it to disk later. - */ - flush_dcache_mft_record_page(ctx->ntfs_ino); - mark_mft_record_dirty(ctx->ntfs_ino); - ntfs_attr_reinit_search_ctx(ctx); - err = ntfs_attr_lookup(ni->type, ni->name, ni->name_len, - CASE_SENSITIVE, 0, NULL, 0, ctx); - if (unlikely(err)) - goto restore_undo_alloc; - /* @m is not used any more so no need to set it. */ - a = ctx->attr; - } - write_lock_irqsave(&ni->size_lock, flags); - ni->allocated_size = new_alloc_size; - a->data.non_resident.allocated_size = cpu_to_sle64(new_alloc_size); - /* - * FIXME: This would fail if @ni is a directory, $MFT, or an index, - * since those can have sparse/compressed set. For example can be - * set compressed even though it is not compressed itself and in that - * case the bit means that files are to be created compressed in the - * directory... At present this is ok as this code is only called for - * regular files, and only for their $DATA attribute(s). - * FIXME: The calculation is wrong if we created a hole above. For now - * it does not matter as we never create holes. - */ - if (NInoSparse(ni) || NInoCompressed(ni)) { - ni->itype.compressed.size += new_alloc_size - allocated_size; - a->data.non_resident.compressed_size = - cpu_to_sle64(ni->itype.compressed.size); - vi->i_blocks = ni->itype.compressed.size >> 9; - } else - vi->i_blocks = new_alloc_size >> 9; - write_unlock_irqrestore(&ni->size_lock, flags); -alloc_done: - if (new_data_size >= 0) { - BUG_ON(new_data_size < - sle64_to_cpu(a->data.non_resident.data_size)); - a->data.non_resident.data_size = cpu_to_sle64(new_data_size); - } -flush_done: - /* Ensure the changes make it to disk. */ - flush_dcache_mft_record_page(ctx->ntfs_ino); - mark_mft_record_dirty(ctx->ntfs_ino); -done: - ntfs_attr_put_search_ctx(ctx); - unmap_mft_record(base_ni); - up_write(&ni->runlist.lock); - ntfs_debug("Done, new_allocated_size 0x%llx.", - (unsigned long long)new_alloc_size); - return new_alloc_size; -restore_undo_alloc: - if (start < 0 || start >= allocated_size) - ntfs_error(vol->sb, "Cannot complete extension of allocation " - "of inode 0x%lx, attribute type 0x%x, because " - "lookup of first attribute extent failed with " - "error code %i.", vi->i_ino, - (unsigned)le32_to_cpu(ni->type), err); - if (err == -ENOENT) - err = -EIO; - ntfs_attr_reinit_search_ctx(ctx); - if (ntfs_attr_lookup(ni->type, ni->name, ni->name_len, CASE_SENSITIVE, - allocated_size >> vol->cluster_size_bits, NULL, 0, - ctx)) { - ntfs_error(vol->sb, "Failed to find last attribute extent of " - "attribute in error code path. Run chkdsk to " - "recover."); - write_lock_irqsave(&ni->size_lock, flags); - ni->allocated_size = new_alloc_size; - /* - * FIXME: This would fail if @ni is a directory... See above. - * FIXME: The calculation is wrong if we created a hole above. - * For now it does not matter as we never create holes. - */ - if (NInoSparse(ni) || NInoCompressed(ni)) { - ni->itype.compressed.size += new_alloc_size - - allocated_size; - vi->i_blocks = ni->itype.compressed.size >> 9; - } else - vi->i_blocks = new_alloc_size >> 9; - write_unlock_irqrestore(&ni->size_lock, flags); - ntfs_attr_put_search_ctx(ctx); - unmap_mft_record(base_ni); - up_write(&ni->runlist.lock); - /* - * The only thing that is now wrong is the allocated size of the - * base attribute extent which chkdsk should be able to fix. - */ - NVolSetErrors(vol); - return err; - } - ctx->attr->data.non_resident.highest_vcn = cpu_to_sle64( - (allocated_size >> vol->cluster_size_bits) - 1); -undo_alloc: - ll = allocated_size >> vol->cluster_size_bits; - if (ntfs_cluster_free(ni, ll, -1, ctx) < 0) { - ntfs_error(vol->sb, "Failed to release allocated cluster(s) " - "in error code path. Run chkdsk to recover " - "the lost cluster(s)."); - NVolSetErrors(vol); - } - m = ctx->mrec; - a = ctx->attr; - /* - * If the runlist truncation fails and/or the search context is no - * longer valid, we cannot resize the attribute record or build the - * mapping pairs array thus we mark the inode bad so that no access to - * the freed clusters can happen. - */ - if (ntfs_rl_truncate_nolock(vol, &ni->runlist, ll) || IS_ERR(m)) { - ntfs_error(vol->sb, "Failed to %s in error code path. Run " - "chkdsk to recover.", IS_ERR(m) ? - "restore attribute search context" : - "truncate attribute runlist"); - NVolSetErrors(vol); - } else if (mp_rebuilt) { - if (ntfs_attr_record_resize(m, a, attr_len)) { - ntfs_error(vol->sb, "Failed to restore attribute " - "record in error code path. Run " - "chkdsk to recover."); - NVolSetErrors(vol); - } else /* if (success) */ { - if (ntfs_mapping_pairs_build(vol, (u8*)a + le16_to_cpu( - a->data.non_resident. - mapping_pairs_offset), attr_len - - le16_to_cpu(a->data.non_resident. - mapping_pairs_offset), rl2, ll, -1, - NULL)) { - ntfs_error(vol->sb, "Failed to restore " - "mapping pairs array in error " - "code path. Run chkdsk to " - "recover."); - NVolSetErrors(vol); - } - flush_dcache_mft_record_page(ctx->ntfs_ino); - mark_mft_record_dirty(ctx->ntfs_ino); - } - } -err_out: - if (ctx) - ntfs_attr_put_search_ctx(ctx); - if (m) - unmap_mft_record(base_ni); - up_write(&ni->runlist.lock); -conv_err_out: - ntfs_debug("Failed. Returning error code %i.", err); - return err; -} - -/** - * ntfs_attr_set - fill (a part of) an attribute with a byte - * @ni: ntfs inode describing the attribute to fill - * @ofs: offset inside the attribute at which to start to fill - * @cnt: number of bytes to fill - * @val: the unsigned 8-bit value with which to fill the attribute - * - * Fill @cnt bytes of the attribute described by the ntfs inode @ni starting at - * byte offset @ofs inside the attribute with the constant byte @val. - * - * This function is effectively like memset() applied to an ntfs attribute. - * Note this function actually only operates on the page cache pages belonging - * to the ntfs attribute and it marks them dirty after doing the memset(). - * Thus it relies on the vm dirty page write code paths to cause the modified - * pages to be written to the mft record/disk. - * - * Return 0 on success and -errno on error. An error code of -ESPIPE means - * that @ofs + @cnt were outside the end of the attribute and no write was - * performed. - */ -int ntfs_attr_set(ntfs_inode *ni, const s64 ofs, const s64 cnt, const u8 val) -{ - ntfs_volume *vol = ni->vol; - struct address_space *mapping; - struct page *page; - u8 *kaddr; - pgoff_t idx, end; - unsigned start_ofs, end_ofs, size; - - ntfs_debug("Entering for ofs 0x%llx, cnt 0x%llx, val 0x%hx.", - (long long)ofs, (long long)cnt, val); - BUG_ON(ofs < 0); - BUG_ON(cnt < 0); - if (!cnt) - goto done; - /* - * FIXME: Compressed and encrypted attributes are not supported when - * writing and we should never have gotten here for them. - */ - BUG_ON(NInoCompressed(ni)); - BUG_ON(NInoEncrypted(ni)); - mapping = VFS_I(ni)->i_mapping; - /* Work out the starting index and page offset. */ - idx = ofs >> PAGE_SHIFT; - start_ofs = ofs & ~PAGE_MASK; - /* Work out the ending index and page offset. */ - end = ofs + cnt; - end_ofs = end & ~PAGE_MASK; - /* If the end is outside the inode size return -ESPIPE. */ - if (unlikely(end > i_size_read(VFS_I(ni)))) { - ntfs_error(vol->sb, "Request exceeds end of attribute."); - return -ESPIPE; - } - end >>= PAGE_SHIFT; - /* If there is a first partial page, need to do it the slow way. */ - if (start_ofs) { - page = read_mapping_page(mapping, idx, NULL); - if (IS_ERR(page)) { - ntfs_error(vol->sb, "Failed to read first partial " - "page (error, index 0x%lx).", idx); - return PTR_ERR(page); - } - /* - * If the last page is the same as the first page, need to - * limit the write to the end offset. - */ - size = PAGE_SIZE; - if (idx == end) - size = end_ofs; - kaddr = kmap_atomic(page); - memset(kaddr + start_ofs, val, size - start_ofs); - flush_dcache_page(page); - kunmap_atomic(kaddr); - set_page_dirty(page); - put_page(page); - balance_dirty_pages_ratelimited(mapping); - cond_resched(); - if (idx == end) - goto done; - idx++; - } - /* Do the whole pages the fast way. */ - for (; idx < end; idx++) { - /* Find or create the current page. (The page is locked.) */ - page = grab_cache_page(mapping, idx); - if (unlikely(!page)) { - ntfs_error(vol->sb, "Insufficient memory to grab " - "page (index 0x%lx).", idx); - return -ENOMEM; - } - kaddr = kmap_atomic(page); - memset(kaddr, val, PAGE_SIZE); - flush_dcache_page(page); - kunmap_atomic(kaddr); - /* - * If the page has buffers, mark them uptodate since buffer - * state and not page state is definitive in 2.6 kernels. - */ - if (page_has_buffers(page)) { - struct buffer_head *bh, *head; - - bh = head = page_buffers(page); - do { - set_buffer_uptodate(bh); - } while ((bh = bh->b_this_page) != head); - } - /* Now that buffers are uptodate, set the page uptodate, too. */ - SetPageUptodate(page); - /* - * Set the page and all its buffers dirty and mark the inode - * dirty, too. The VM will write the page later on. - */ - set_page_dirty(page); - /* Finally unlock and release the page. */ - unlock_page(page); - put_page(page); - balance_dirty_pages_ratelimited(mapping); - cond_resched(); - } - /* If there is a last partial page, need to do it the slow way. */ - if (end_ofs) { - page = read_mapping_page(mapping, idx, NULL); - if (IS_ERR(page)) { - ntfs_error(vol->sb, "Failed to read last partial page " - "(error, index 0x%lx).", idx); - return PTR_ERR(page); - } - kaddr = kmap_atomic(page); - memset(kaddr, val, end_ofs); - flush_dcache_page(page); - kunmap_atomic(kaddr); - set_page_dirty(page); - put_page(page); - balance_dirty_pages_ratelimited(mapping); - cond_resched(); - } -done: - ntfs_debug("Done."); - return 0; -} - -#endif /* NTFS_RW */ |