From: Darrick J. Wong <djwong@xxxxxxxxxx>
Add a new NVLOOKUP flag to signal that the caller wants to look up an
extended attribute by name and value. This only works with shortform
and local attributes. Only parent pointers need this functionality
and parent pointers cannot be remote xattrs, so this limitation is ok
for now.
Signed-off-by: Darrick J. Wong <djwong@xxxxxxxxxx>
---
libxfs/xfs_attr_leaf.c | 45 +++++++++++++++++++++++++++++++++++++--------
libxfs/xfs_da_btree.h | 4 +++-
2 files changed, 40 insertions(+), 9 deletions(-)
diff --git a/libxfs/xfs_attr_leaf.c b/libxfs/xfs_attr_leaf.c
index 6cac25312..b095b25a6 100644
--- a/libxfs/xfs_attr_leaf.c
+++ b/libxfs/xfs_attr_leaf.c
@@ -470,10 +470,12 @@ xfs_attr3_leaf_read(
*/
static bool
xfs_attr_match(
- struct xfs_da_args *args,
- uint8_t namelen,
- unsigned char *name,
- int flags)
+ const struct xfs_da_args *args,
+ uint8_t namelen,
+ const unsigned char *name,
+ unsigned int valuelen,
+ const void *value,
+ int flags)
{
if (args->namelen != namelen)
@@ -481,6 +483,23 @@ xfs_attr_match(
if (memcmp(args->name, name, namelen) != 0)
return false;
+ if (args->op_flags & XFS_DA_OP_NVLOOKUP) {
+ if (args->valuelen != valuelen)
+ return false;
+ if (args->valuelen && !value) {
+ /* not implemented for remote values */
+ ASSERT(0);
+ return false;
+ }
+ if (valuelen && !args->value) {
+ /* caller gave us valuelen > 0 but no value?? */
+ ASSERT(0);
+ return false;
+ }
+ if (valuelen > 0 && memcmp(args->value, value, valuelen) != 0)
+ return false;
+ }
+
/* Recovery ignores the INCOMPLETE flag. */
if ((args->op_flags & XFS_DA_OP_RECOVERY) &&
args->attr_filter == (flags & XFS_ATTR_NSP_ONDISK_MASK))
@@ -499,6 +518,10 @@ xfs_attr_copy_value(
unsigned char *value,
int valuelen)
{
+ /* vlookups already supplied the attr value; don't copy anything */
+ if (args->op_flags & XFS_DA_OP_NVLOOKUP)
+ return 0;
+
/*
* No copy if all we have to do is get the length
*/
@@ -723,6 +746,7 @@ xfs_attr_sf_findname(
base += size, i++) {
size = xfs_attr_sf_entsize(sfe);
if (!xfs_attr_match(args, sfe->namelen, sfe->nameval,
+ sfe->valuelen, &sfe->nameval[sfe->namelen],
sfe->flags))
continue;
break;
@@ -891,6 +915,7 @@ xfs_attr_shortform_lookup(xfs_da_args_t *args)
for (i = 0; i < sf->hdr.count;
sfe = xfs_attr_sf_nextentry(sfe), i++) {
if (xfs_attr_match(args, sfe->namelen, sfe->nameval,
+ sfe->valuelen, &sfe->nameval[sfe->namelen],
sfe->flags))
return -EEXIST;
}
@@ -918,6 +943,7 @@ xfs_attr_shortform_getvalue(
for (i = 0; i < sf->hdr.count;
sfe = xfs_attr_sf_nextentry(sfe), i++) {
if (xfs_attr_match(args, sfe->namelen, sfe->nameval,
+ sfe->valuelen, &sfe->nameval[sfe->namelen],
sfe->flags))
return xfs_attr_copy_value(args,
&sfe->nameval[args->namelen], sfe->valuelen);
@@ -970,7 +996,7 @@ xfs_attr_shortform_to_leaf(
nargs.total = args->total;
nargs.whichfork = XFS_ATTR_FORK;
nargs.trans = args->trans;
- nargs.op_flags = XFS_DA_OP_OKNOENT;
+ nargs.op_flags = XFS_DA_OP_OKNOENT | XFS_DA_OP_NVLOOKUP;
sfe = &sf->list[0];
for (i = 0; i < sf->hdr.count; i++) {
@@ -1180,7 +1206,7 @@ xfs_attr3_leaf_to_shortform(
nargs.total = args->total;
nargs.whichfork = XFS_ATTR_FORK;
nargs.trans = args->trans;
- nargs.op_flags = XFS_DA_OP_OKNOENT;
+ nargs.op_flags = XFS_DA_OP_OKNOENT | XFS_DA_OP_NVLOOKUP;
for (i = 0; i < ichdr.count; entry++, i++) {
if (entry->flags & XFS_ATTR_INCOMPLETE)
@@ -2479,14 +2505,17 @@ xfs_attr3_leaf_lookup_int(
if (entry->flags & XFS_ATTR_LOCAL) {
name_loc = xfs_attr3_leaf_name_local(leaf, probe);
if (!xfs_attr_match(args, name_loc->namelen,
- name_loc->nameval, entry->flags))
+ name_loc->nameval,
+ be16_to_cpu(name_loc->valuelen),
+ &name_loc->nameval[name_loc->namelen],
+ entry->flags))
continue;
args->index = probe;
return -EEXIST;
} else {
name_rmt = xfs_attr3_leaf_name_remote(leaf, probe);
if (!xfs_attr_match(args, name_rmt->namelen,
- name_rmt->name, entry->flags))
+ name_rmt->name, 0, NULL, entry->flags))
continue;
args->index = probe;
args->rmtvaluelen = be32_to_cpu(name_rmt->valuelen);
diff --git a/libxfs/xfs_da_btree.h b/libxfs/xfs_da_btree.h
index ffa3df5b2..94a544fc8 100644
--- a/libxfs/xfs_da_btree.h
+++ b/libxfs/xfs_da_btree.h
@@ -93,6 +93,7 @@ typedef struct xfs_da_args {
#define XFS_DA_OP_REMOVE (1u << 6) /* this is a remove operation */
#define XFS_DA_OP_RECOVERY (1u << 7) /* Log recovery operation */
#define XFS_DA_OP_LOGGED (1u << 8) /* Use intent items to track op */
+#define XFS_DA_OP_NVLOOKUP (1u << 9) /* Match local attr on name+value */
#define XFS_DA_OP_FLAGS \
{ XFS_DA_OP_JUSTCHECK, "JUSTCHECK" }, \
@@ -103,7 +104,8 @@ typedef struct xfs_da_args {
{ XFS_DA_OP_NOTIME, "NOTIME" }, \
{ XFS_DA_OP_REMOVE, "REMOVE" }, \
{ XFS_DA_OP_RECOVERY, "RECOVERY" }, \
- { XFS_DA_OP_LOGGED, "LOGGED" }
+ { XFS_DA_OP_LOGGED, "LOGGED" }, \
+ { XFS_DA_OP_NVLOOKUP, "NVLOOKUP" }
/*
* Storage for holding state during Btree searches and split/join ops.
