diff options
Diffstat (limited to 'fs/ntfs/attrib.c')
| -rw-r--r-- | fs/ntfs/attrib.c | 125 |
1 files changed, 107 insertions, 18 deletions
diff --git a/fs/ntfs/attrib.c b/fs/ntfs/attrib.c index cd0f9e740b14..3f9a4ff42ee5 100644 --- a/fs/ntfs/attrib.c +++ b/fs/ntfs/attrib.c @@ -43,6 +43,9 @@ * 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. + * * Locking: - The runlist must be locked for writing. * - This function modifies the runlist. */ @@ -54,6 +57,7 @@ int ntfs_map_runlist_nolock(ntfs_inode *ni, VCN vcn) ATTR_RECORD *a; ntfs_attr_search_ctx *ctx; runlist_element *rl; + unsigned long flags; int err = 0; ntfs_debug("Mapping runlist part containing vcn 0x%llx.", @@ -85,8 +89,11 @@ int ntfs_map_runlist_nolock(ntfs_inode *ni, VCN vcn) * 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)) + if (unlikely(!a->data.non_resident.lowest_vcn && end_vcn <= 1)) { + read_lock_irqsave(&ni->size_lock, flags); end_vcn = ni->allocated_size >> ni->vol->cluster_size_bits; + read_unlock_irqrestore(&ni->size_lock, flags); + } if (unlikely(vcn >= end_vcn)) { err = -ENOENT; goto err_out; @@ -165,6 +172,7 @@ 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; ntfs_debug("Entering for i_ino 0x%lx, vcn 0x%llx, %s_locked.", @@ -173,6 +181,14 @@ LCN ntfs_attr_vcn_to_lcn_nolock(ntfs_inode *ni, const VCN vcn, BUG_ON(!ni); 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); @@ -255,6 +271,7 @@ retry_remap: runlist_element *ntfs_attr_find_vcn_nolock(ntfs_inode *ni, const VCN vcn, const BOOL write_locked) { + unsigned long flags; runlist_element *rl; int err = 0; BOOL is_retry = FALSE; @@ -265,6 +282,14 @@ runlist_element *ntfs_attr_find_vcn_nolock(ntfs_inode *ni, const VCN vcn, BUG_ON(!ni); 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)) { @@ -528,6 +553,11 @@ int load_attribute_list(ntfs_volume *vol, runlist *runlist, u8 *al_start, 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); @@ -1247,6 +1277,46 @@ int ntfs_attr_record_resize(MFT_RECORD *m, ATTR_RECORD *a, u32 new_size) } /** + * 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 * @@ -1302,6 +1372,12 @@ int ntfs_attr_make_non_resident(ntfs_inode *ni) 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. */ @@ -1377,10 +1453,15 @@ int ntfs_attr_make_non_resident(ntfs_inode *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; + 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 @@ -1419,24 +1500,23 @@ int ntfs_attr_make_non_resident(ntfs_inode *ni) 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); + if (NInoSparse(ni) || NInoCompressed(ni)) { + 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); @@ -1446,16 +1526,19 @@ int ntfs_attr_make_non_resident(ntfs_inode *ni) 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; + if (NInoSparse(ni) || NInoCompressed(ni)) { + ni->itype.compressed.size = ni->allocated_size; + 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; + } write_unlock_irqrestore(&ni->size_lock, flags); /* * This needs to be last since the address space operations ->readpage @@ -1603,6 +1686,12 @@ int ntfs_attr_set(ntfs_inode *ni, const s64 ofs, const s64 cnt, const u8 val) 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_CACHE_SHIFT; |