diff options
Diffstat (limited to 'fs/ntfs/attrib.c')
| -rw-r--r-- | fs/ntfs/attrib.c | 630 |
1 files changed, 544 insertions, 86 deletions
diff --git a/fs/ntfs/attrib.c b/fs/ntfs/attrib.c index 1ff7f90..cd0f9e7 100644 --- a/fs/ntfs/attrib.c +++ b/fs/ntfs/attrib.c @@ -1,7 +1,7 @@ /** * attrib.c - NTFS attribute operations. Part of the Linux-NTFS project. * - * Copyright (c) 2001-2004 Anton Altaparmakov + * Copyright (c) 2001-2005 Anton Altaparmakov * Copyright (c) 2002 Richard Russon * * This program/include file is free software; you can redistribute it and/or @@ -21,88 +21,217 @@ */ #include <linux/buffer_head.h> +#include <linux/swap.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 - map (a part of) a runlist of an ntfs inode + * 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 * * Map the part of a runlist containing the @vcn of the ntfs inode @ni. * - * Return 0 on success and -errno on error. + * 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 lock for writing and modifies the runlist. + * Locking: - The runlist must be locked for writing. + * - This function modifies the runlist. */ -int ntfs_map_runlist(ntfs_inode *ni, VCN vcn) +int ntfs_map_runlist_nolock(ntfs_inode *ni, VCN vcn) { + VCN end_vcn; ntfs_inode *base_ni; + MFT_RECORD *m; + ATTR_RECORD *a; ntfs_attr_search_ctx *ctx; - MFT_RECORD *mrec; + runlist_element *rl; int err = 0; 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; - - mrec = map_mft_record(base_ni); - if (IS_ERR(mrec)) - return PTR_ERR(mrec); - ctx = ntfs_attr_get_search_ctx(base_ni, mrec); + 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; } err = ntfs_attr_lookup(ni->type, ni->name, ni->name_len, CASE_SENSITIVE, vcn, NULL, 0, ctx); - if (unlikely(err)) - goto put_err_out; + if (unlikely(err)) { + if (err == -ENOENT) + err = -EIO; + goto err_out; + } + 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(!a->data.non_resident.lowest_vcn && end_vcn <= 1)) + end_vcn = ni->allocated_size >> ni->vol->cluster_size_bits; + if (unlikely(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 (likely(ctx)) + ntfs_attr_put_search_ctx(ctx); + unmap_mft_record(base_ni); + 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 modifies 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)) { - runlist_element *rl; + LCN_RL_NOT_MAPPED)) + err = ntfs_map_runlist_nolock(ni, vcn); + up_write(&ni->runlist.lock); + return err; +} - rl = ntfs_mapping_pairs_decompress(ni->vol, ctx->attr, - ni->runlist.rl); - if (IS_ERR(rl)) - err = PTR_ERR(rl); - else - ni->runlist.rl = rl; +/** + * 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; + BOOL is_retry = FALSE; + + 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(!ni); + BUG_ON(!NInoNonResident(ni)); + BUG_ON(vcn < 0); +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; } - up_write(&ni->runlist.lock); + if (lcn != LCN_RL_NOT_MAPPED) { + if (lcn != LCN_ENOENT) + lcn = LCN_EIO; + } else if (!is_retry) { + int err; -put_err_out: - ntfs_attr_put_search_ctx(ctx); -err_out: - unmap_mft_record(base_ni); - return 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); + 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_find_vcn - find a vcn in the runlist described by an ntfs inode - * @ni: ntfs inode describing the runlist to search - * @vcn: vcn to find - * @need_write: if false, lock for reading and if true, lock for writing + * 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 + * @write_locked: true if the runlist is locked for writing * * 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. - * The runlist is left locked and the caller has to unlock it. If @need_write - * is true, the runlist is locked for writing and if @need_write is false, the - * runlist is locked for reading. In the error case, the runlist is not left - * locked. + * + * 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. * * 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 @@ -118,34 +247,29 @@ err_out: * -ENOMEM - Not enough memory to map runlist. * -EIO - Critical error (runlist/file is corrupt, i/o error, etc). * - * Locking: - The runlist must be unlocked on entry. - * - On failing return, the runlist is unlocked. - * - On successful return, the runlist is locked. If @need_write us - * true, it is locked for writing. Otherwise is is locked for - * reading. + * 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. */ -runlist_element *ntfs_find_vcn(ntfs_inode *ni, const VCN vcn, - const BOOL need_write) +runlist_element *ntfs_attr_find_vcn_nolock(ntfs_inode *ni, const VCN vcn, + const BOOL write_locked) { runlist_element *rl; int err = 0; BOOL is_retry = FALSE; - ntfs_debug("Entering for i_ino 0x%lx, vcn 0x%llx, lock for %sing.", + ntfs_debug("Entering for i_ino 0x%lx, vcn 0x%llx, %s_locked.", ni->mft_no, (unsigned long long)vcn, - !need_write ? "read" : "writ"); + write_locked ? "write" : "read"); BUG_ON(!ni); BUG_ON(!NInoNonResident(ni)); BUG_ON(vcn < 0); -lock_retry_remap: - if (!need_write) - down_read(&ni->runlist.lock); - else - down_write(&ni->runlist.lock); +retry_remap: rl = ni->runlist.rl; if (likely(rl && vcn >= rl[0].vcn)) { while (likely(rl->length)) { - if (likely(vcn < rl[1].vcn)) { + if (unlikely(vcn < rl[1].vcn)) { if (likely(rl->lcn >= LCN_HOLE)) { ntfs_debug("Done."); return rl; @@ -161,30 +285,41 @@ lock_retry_remap: err = -EIO; } } - if (!need_write) - up_read(&ni->runlist.lock); - else - up_write(&ni->runlist.lock); if (!err && !is_retry) { /* * The @vcn is in an unmapped region, map the runlist and * retry. */ - err = ntfs_map_runlist(ni, vcn); + 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); + if (!write_locked) { + up_write(&ni->runlist.lock); + down_read(&ni->runlist.lock); + } if (likely(!err)) { is_retry = TRUE; - goto lock_retry_remap; + goto retry_remap; } /* - * -EINVAL and -ENOENT coming from a failed mapping attempt are - * equivalent to i/o errors for us as they should not happen in - * our code paths. + * -EINVAL coming from a failed mapping attempt is equivalent + * to i/o error for us as it should not happen in our code + * paths. */ - if (err == -EINVAL || err == -ENOENT) + if (err == -EINVAL) err = -EIO; } else if (!err) err = -EIO; - ntfs_error(ni->vol->sb, "Failed with error code %i.", err); + if (err != -ENOENT) + ntfs_error(ni->vol->sb, "Failed with error code %i.", err); return ERR_PTR(err); } @@ -870,15 +1005,14 @@ int ntfs_attr_lookup(const ATTR_TYPE type, const ntfschar *name, static inline void ntfs_attr_init_search_ctx(ntfs_attr_search_ctx *ctx, ntfs_inode *ni, MFT_RECORD *mrec) { - ctx->mrec = mrec; - /* Sanity checks are performed elsewhere. */ - ctx->attr = (ATTR_RECORD*)((u8*)mrec + le16_to_cpu(mrec->attrs_offset)); - ctx->is_first = TRUE; - ctx->ntfs_ino = ni; - ctx->al_entry = NULL; - ctx->base_ntfs_ino = NULL; - ctx->base_mrec = NULL; - ctx->base_attr = NULL; + *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, + }; } /** @@ -945,6 +1079,8 @@ void ntfs_attr_put_search_ctx(ntfs_attr_search_ctx *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 @@ -1024,27 +1160,21 @@ int ntfs_attr_size_bounds_check(const ntfs_volume *vol, const ATTR_TYPE type, * 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, or + * 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; - /* - * $DATA is always allowed to be non-resident even if $AttrDef does not - * specify this in the flags of the $DATA attribute definition record. - */ - if (type == AT_DATA) - return 0; /* 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 & CAN_BE_NON_RESIDENT) - return 0; - return -EPERM; + if (ad->flags & ATTR_DEF_RESIDENT) + return -EPERM; + return 0; } /** @@ -1067,9 +1197,9 @@ int ntfs_attr_can_be_non_resident(const ntfs_volume *vol, const ATTR_TYPE type) */ int ntfs_attr_can_be_resident(const ntfs_volume *vol, const ATTR_TYPE type) { - if (type != AT_INDEX_ALLOCATION && type != AT_EA) - return 0; - return -EPERM; + if (type == AT_INDEX_ALLOCATION || type == AT_EA) + return -EPERM; + return 0; } /** @@ -1117,6 +1247,328 @@ int ntfs_attr_record_resize(MFT_RECORD *m, ATTR_RECORD *a, u32 new_size) } /** + * ntfs_attr_make_non_resident - convert a resident to a non-resident attribute + * @ni: ntfs inode describing the attribute to convert + * + * Convert the resident ntfs attribute described by the ntfs inode @ni to a + * non-resident one. + * + * 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_sem on the inode. + */ +int ntfs_attr_make_non_resident(ntfs_inode *ni) +{ + 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; + } + /* + * The size needs to be aligned to a cluster boundary for allocation + * purposes. + */ + new_size = (i_size_read(vi) + vol->cluster_size - 1) & + ~(vol->cluster_size - 1); + if (new_size > 0) { + runlist_element *rl2; + + /* + * 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); + 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; + } + /* Change the runlist terminator to LCN_ENOENT. */ + rl2 = rl; + while (rl2->length) + rl2++; + BUG_ON(rl2->lcn != LCN_RL_NOT_MAPPED); + rl2->lcn = LCN_ENOENT; + } 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. + * We assume the attribute is not compressed or sparse. + */ + 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 != i_size_read(vi)); + if (page && !PageUptodate(page)) { + kaddr = kmap_atomic(page, KM_USER0); + memcpy(kaddr, (u8*)a + + le16_to_cpu(a->data.resident.value_offset), + attr_size); + memset(kaddr + attr_size, 0, PAGE_CACHE_SIZE - attr_size); + kunmap_atomic(kaddr, KM_USER0); + 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); + /* + * FIXME: For now just clear all of these as we do not support them + * when writing. + */ + a->flags &= cpu_to_le16(0xffff & ~le16_to_cpu(ATTR_IS_SPARSE | + ATTR_IS_ENCRYPTED | ATTR_COMPRESSION_MASK)); + /* 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); + a->data.non_resident.compression_unit = 0; + 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); + /* 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. */ + /* + * FIXME: For now just clear all of these as we do not support them + * when writing. + */ + NInoClearSparse(ni); + NInoClearEncrypted(ni); + NInoClearCompressed(ni); + ni->runlist.rl = rl; + write_lock_irqsave(&ni->size_lock, flags); + ni->allocated_size = new_size; + write_unlock_irqrestore(&ni->size_lock, flags); + /* + * This needs to be last since the address space operations ->readpage + * and ->writepage can run concurrently with us as they are not + * serialized on i_sem. 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); + mark_page_accessed(page); + page_cache_release(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, KM_USER0); + memcpy((u8*)a + mp_ofs, kaddr, attr_size); + kunmap_atomic(kaddr, KM_USER0); + } + /* 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); + page_cache_release(page); + } + if (err == -EINVAL) + err = -EIO; + 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 @@ -1127,6 +1579,10 @@ int ntfs_attr_record_resize(MFT_RECORD *m, ATTR_RECORD *a, u32 new_size) * byte offset @ofs inside the attribute with the constant byte @val. * * This function is effectively like memset() applied to an ntfs attribute. + * Note thie 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 @@ -1155,7 +1611,7 @@ int ntfs_attr_set(ntfs_inode *ni, const s64 ofs, const s64 cnt, const u8 val) end = ofs + cnt; end_ofs = end & ~PAGE_CACHE_MASK; /* If the end is outside the inode size return -ESPIPE. */ - if (unlikely(end > VFS_I(ni)->i_size)) { + if (unlikely(end > i_size_read(VFS_I(ni)))) { ntfs_error(vol->sb, "Request exceeds end of attribute."); return -ESPIPE; } @@ -1256,3 +1712,5 @@ done: ntfs_debug("Done."); return 0; } + +#endif /* NTFS_RW */ |
