summaryrefslogtreecommitdiffstats
path: root/fs/ntfs/attrib.c
diff options
context:
space:
mode:
Diffstat (limited to 'fs/ntfs/attrib.c')
-rw-r--r--fs/ntfs/attrib.c125
1 files changed, 107 insertions, 18 deletions
diff --git a/fs/ntfs/attrib.c b/fs/ntfs/attrib.c
index cd0f9e7..3f9a4ff 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;
OpenPOWER on IntegriCloud