[PATCH 03/12] xfs: allow xattr matching on name and value for local/sf attrs

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



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>
---
 fs/xfs/libxfs/xfs_attr_leaf.c |   45 ++++++++++++++++++++++++++++++++++-------
 fs/xfs/libxfs/xfs_da_btree.h  |    4 +++-
 2 files changed, 40 insertions(+), 9 deletions(-)


diff --git a/fs/xfs/libxfs/xfs_attr_leaf.c b/fs/xfs/libxfs/xfs_attr_leaf.c
index 1f3febeccbe0..884528ca3b49 100644
--- a/fs/xfs/libxfs/xfs_attr_leaf.c
+++ b/fs/xfs/libxfs/xfs_attr_leaf.c
@@ -508,10 +508,12 @@ 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)
@@ -519,6 +521,23 @@ 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))
@@ -537,6 +556,10 @@ 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
 	 */
@@ -761,6 +784,7 @@ 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;
@@ -929,6 +953,7 @@ 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;
 	}
@@ -956,6 +981,7 @@ 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);
@@ -1008,7 +1034,7 @@ 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;
 	nargs.owner = args->owner;
 
 	sfe = &sf->list[0];
@@ -1229,7 +1255,7 @@ 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;
 	nargs.owner = args->owner;
 
 	for (i = 0; i < ichdr.count; entry++, i++) {
@@ -2532,14 +2558,17 @@ 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/fs/xfs/libxfs/xfs_da_btree.h b/fs/xfs/libxfs/xfs_da_btree.h
index 1f5b3c3f0deb..091750b2d42a 100644
--- a/fs/xfs/libxfs/xfs_da_btree.h
+++ b/fs/xfs/libxfs/xfs_da_btree.h
@@ -94,6 +94,7 @@ 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" }, \
@@ -104,7 +105,8 @@ 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.




[Index of Archives]     [XFS Filesystem Development (older mail)]     [Linux Filesystem Development]     [Linux Audio Users]     [Yosemite Trails]     [Linux Kernel]     [Linux RAID]     [Linux SCSI]


  Powered by Linux