[v2,04/21] xfsprogs: Add xfs_has_attr and subroutines
diff mbox series

Message ID 20190905221855.17555-5-allison.henderson@oracle.com
State Superseded
Headers show
Series
  • Delayed Attributes
Related show

Commit Message

Allison Collins Sept. 5, 2019, 10:18 p.m. UTC
This patch adds a new functions to check for the existence of
an attribute.  Subroutines are also added to handle the cases
of leaf blocks, nodes or shortform.  Common code that appears
in existing attr add and remove functions have been factored
out to help reduce the appearence of duplicated code.  We will
need these routines later for delayed attributes since delayed
operations cannot return error codes.

Signed-off-by: Allison Collins <allison.henderson@oracle.com>
---
 libxfs/xfs_attr.c      | 150 ++++++++++++++++++++++++++++++++-----------------
 libxfs/xfs_attr.h      |   1 +
 libxfs/xfs_attr_leaf.c |  92 ++++++++++++++++++++----------
 libxfs/xfs_attr_leaf.h |   2 +
 4 files changed, 162 insertions(+), 83 deletions(-)

Patch
diff mbox series

diff --git a/libxfs/xfs_attr.c b/libxfs/xfs_attr.c
index f036460..0e45b0d 100644
--- a/libxfs/xfs_attr.c
+++ b/libxfs/xfs_attr.c
@@ -45,6 +45,7 @@  STATIC int xfs_attr_shortform_addname(xfs_da_args_t *args);
 STATIC int xfs_attr_leaf_get(xfs_da_args_t *args);
 STATIC int xfs_attr_leaf_addname(xfs_da_args_t *args);
 STATIC int xfs_attr_leaf_removename(xfs_da_args_t *args);
+STATIC int xfs_leaf_has_attr(struct xfs_da_args *args, struct xfs_buf **bp);
 
 /*
  * Internal routines when attribute list is more than one block.
@@ -52,6 +53,8 @@  STATIC int xfs_attr_leaf_removename(xfs_da_args_t *args);
 STATIC int xfs_attr_node_get(xfs_da_args_t *args);
 STATIC int xfs_attr_node_addname(xfs_da_args_t *args);
 STATIC int xfs_attr_node_removename(xfs_da_args_t *args);
+STATIC int xfs_attr_node_hasname(xfs_da_args_t *args,
+				 struct xfs_da_state **state);
 STATIC int xfs_attr_fillstate(xfs_da_state_t *state);
 STATIC int xfs_attr_refillstate(xfs_da_state_t *state);
 
@@ -275,6 +278,32 @@  xfs_attr_set_args(
 }
 
 /*
+ * Return EEXIST if attr is found, or ENOATTR if not
+ */
+int
+xfs_has_attr(
+	struct xfs_da_args      *args)
+{
+	struct xfs_inode        *dp = args->dp;
+	struct xfs_buf		*bp;
+	int                     error;
+
+	if (!xfs_inode_hasattr(dp)) {
+		error = -ENOATTR;
+	} else if (dp->i_d.di_aformat == XFS_DINODE_FMT_LOCAL) {
+		ASSERT(dp->i_afp->if_flags & XFS_IFINLINE);
+		error = xfs_shortform_has_attr(args, NULL, NULL);
+	} else if (xfs_bmap_one_block(dp, XFS_ATTR_FORK)) {
+		error = xfs_leaf_has_attr(args, &bp);
+		xfs_trans_brelse(args->trans, bp);
+	} else {
+		error = xfs_attr_node_hasname(args, NULL);
+	}
+
+	return error;
+}
+
+/*
  * Remove the attribute specified in @args.
  */
 int
@@ -540,26 +569,17 @@  STATIC int
 xfs_attr_leaf_addname(
 	struct xfs_da_args	*args)
 {
-	struct xfs_inode	*dp;
 	struct xfs_buf		*bp;
 	int			retval, error, forkoff;
+	struct xfs_inode	*dp = args->dp;
 
 	trace_xfs_attr_leaf_addname(args);
 
 	/*
-	 * Read the (only) block in the attribute list in.
-	 */
-	dp = args->dp;
-	args->blkno = 0;
-	error = xfs_attr3_leaf_read(args->trans, args->dp, args->blkno, -1, &bp);
-	if (error)
-		return error;
-
-	/*
 	 * Look up the given attribute in the leaf block.  Figure out if
 	 * the given flags produce an error or call for an atomic rename.
 	 */
-	retval = xfs_attr3_leaf_lookup_int(bp, args);
+	retval = xfs_leaf_has_attr(args, &bp);
 	if ((args->name.type & ATTR_REPLACE) && (retval == -ENOATTR)) {
 		xfs_trans_brelse(args->trans, bp);
 		return retval;
@@ -711,6 +731,25 @@  xfs_attr_leaf_addname(
 }
 
 /*
+ * Return EEXIST if attr is found, or ENOATTR if not
+ */
+STATIC int
+xfs_leaf_has_attr(
+	struct xfs_da_args      *args,
+	struct xfs_buf		**bp)
+{
+	int                     error = 0;
+
+	args->blkno = 0;
+	error = xfs_attr3_leaf_read(args->trans, args->dp,
+			args->blkno, XFS_DABUF_MAP_NOMAPPING, bp);
+	if (error)
+		return error;
+
+	return xfs_attr3_leaf_lookup_int(*bp, args);
+}
+
+/*
  * Remove a name from the leaf attribute list structure
  *
  * This leaf block cannot have a "remote" value, we only call this routine
@@ -730,12 +769,8 @@  xfs_attr_leaf_removename(
 	 * Remove the attribute.
 	 */
 	dp = args->dp;
-	args->blkno = 0;
-	error = xfs_attr3_leaf_read(args->trans, args->dp, args->blkno, -1, &bp);
-	if (error)
-		return error;
 
-	error = xfs_attr3_leaf_lookup_int(bp, args);
+	error = xfs_leaf_has_attr(args, &bp);
 	if (error == -ENOATTR) {
 		xfs_trans_brelse(args->trans, bp);
 		return error;
@@ -772,12 +807,7 @@  xfs_attr_leaf_get(xfs_da_args_t *args)
 
 	trace_xfs_attr_leaf_get(args);
 
-	args->blkno = 0;
-	error = xfs_attr3_leaf_read(args->trans, args->dp, args->blkno, -1, &bp);
-	if (error)
-		return error;
-
-	error = xfs_attr3_leaf_lookup_int(bp, args);
+	error = xfs_leaf_has_attr(args, &bp);
 	if (error != -EEXIST)  {
 		xfs_trans_brelse(args->trans, bp);
 		return error;
@@ -791,6 +821,43 @@  xfs_attr_leaf_get(xfs_da_args_t *args)
 	return error;
 }
 
+/*
+ * Return EEXIST if attr is found, or ENOATTR if not
+ * statep: If not null is set to point at the found state.  Caller will
+ * 	   be responsible for freeing the state in this case.
+ */
+STATIC int
+xfs_attr_node_hasname(
+	struct xfs_da_args	*args,
+	struct xfs_da_state	**statep)
+{
+	struct xfs_da_state	*state;
+	struct xfs_inode	*dp;
+	int			retval, error;
+
+	/*
+	 * Tie a string around our finger to remind us where we are.
+	 */
+	dp = args->dp;
+	state = xfs_da_state_alloc();
+	state->args = args;
+	state->mp = dp->i_mount;
+
+	/*
+	 * Search to see if name exists, and get back a pointer to it.
+	 */
+	error = xfs_da3_node_lookup_int(state, &retval);
+	if (error == 0)
+		error = retval;
+
+	if (statep != NULL)
+		*statep = state;
+	else
+		xfs_da_state_free(state);
+
+	return error;
+}
+
 /*========================================================================
  * External routines when attribute list size > geo->blksize
  *========================================================================*/
@@ -823,17 +890,14 @@  xfs_attr_node_addname(
 	dp = args->dp;
 	mp = dp->i_mount;
 restart:
-	state = xfs_da_state_alloc();
-	state->args = args;
-	state->mp = mp;
-
 	/*
 	 * Search to see if name already exists, and get back a pointer
 	 * to where it should go.
 	 */
-	error = xfs_da3_node_lookup_int(state, &retval);
-	if (error)
+	error = xfs_attr_node_hasname(args, &state);
+	if (error == -EEXIST)
 		goto out;
+
 	blk = &state->path.blk[ state->path.active-1 ];
 	ASSERT(blk->magic == XFS_ATTR_LEAF_MAGIC);
 	if ((args->name.type & ATTR_REPLACE) && (retval == -ENOATTR)) {
@@ -1038,29 +1102,15 @@  xfs_attr_node_removename(
 {
 	struct xfs_da_state	*state;
 	struct xfs_da_state_blk	*blk;
-	struct xfs_inode	*dp;
 	struct xfs_buf		*bp;
 	int			retval, error, forkoff;
+	struct xfs_inode	*dp = args->dp;
 
 	trace_xfs_attr_node_removename(args);
 
-	/*
-	 * Tie a string around our finger to remind us where we are.
-	 */
-	dp = args->dp;
-	state = xfs_da_state_alloc();
-	state->args = args;
-	state->mp = dp->i_mount;
-
-	/*
-	 * Search to see if name exists, and get back a pointer to it.
-	 */
-	error = xfs_da3_node_lookup_int(state, &retval);
-	if (error || (retval != -EEXIST)) {
-		if (error == 0)
-			error = retval;
+	error = xfs_attr_node_hasname(args, &state);
+	if (error != -EEXIST)
 		goto out;
-	}
 
 	/*
 	 * If there is an out-of-line value, de-allocate the blocks.
@@ -1280,17 +1330,13 @@  xfs_attr_node_get(xfs_da_args_t *args)
 
 	trace_xfs_attr_node_get(args);
 
-	state = xfs_da_state_alloc();
-	state->args = args;
-	state->mp = args->dp->i_mount;
-
 	/*
 	 * Search to see if name exists, and get back a pointer to it.
 	 */
-	error = xfs_da3_node_lookup_int(state, &retval);
-	if (error) {
+	error = xfs_attr_node_hasname(args, &state);
+	if (error != -EEXIST) {
 		retval = error;
-	} else if (retval == -EEXIST) {
+	} else {
 		blk = &state->path.blk[ state->path.active-1 ];
 		ASSERT(blk->bp != NULL);
 		ASSERT(blk->magic == XFS_ATTR_LEAF_MAGIC);
diff --git a/libxfs/xfs_attr.h b/libxfs/xfs_attr.h
index aa7261a..6bd783c 100644
--- a/libxfs/xfs_attr.h
+++ b/libxfs/xfs_attr.h
@@ -148,6 +148,7 @@  int xfs_attr_set(struct xfs_inode *dp, struct xfs_name *name,
 		 unsigned char *value, int valuelen);
 int xfs_attr_set_args(struct xfs_da_args *args);
 int xfs_attr_remove(struct xfs_inode *dp, struct xfs_name *name);
+int xfs_has_attr(struct xfs_da_args *args);
 int xfs_attr_remove_args(struct xfs_da_args *args);
 int xfs_attr_list(struct xfs_inode *dp, char *buffer, int bufsize,
 		  int flags, struct attrlist_cursor_kern *cursor);
diff --git a/libxfs/xfs_attr_leaf.c b/libxfs/xfs_attr_leaf.c
index b8136ed..1b39477 100644
--- a/libxfs/xfs_attr_leaf.c
+++ b/libxfs/xfs_attr_leaf.c
@@ -542,6 +542,53 @@  xfs_attr_shortform_create(xfs_da_args_t *args)
 }
 
 /*
+ * Return EEXIST if attr is found, or ENOATTR if not
+ * args:  args containing attribute name and namelen
+ * sfep:  If not null, pointer will be set to the last attr entry found
+ * basep: If not null, pointer is set to the byte offset of the entry in the
+ *	  list
+ */
+int
+xfs_shortform_has_attr(
+	struct xfs_da_args	 *args,
+	struct xfs_attr_sf_entry **sfep,
+	int			 *basep)
+{
+	struct xfs_attr_shortform *sf;
+	struct xfs_attr_sf_entry *sfe;
+	int			base = sizeof(struct xfs_attr_sf_hdr);
+	int			size = 0;
+	int			end;
+	int			i;
+
+	base = sizeof(struct xfs_attr_sf_hdr);
+	sf = (struct xfs_attr_shortform *)args->dp->i_afp->if_u1.if_data;
+	sfe = &sf->list[0];
+	end = sf->hdr.count;
+	for (i = 0; i < end; sfe = XFS_ATTR_SF_NEXTENTRY(sfe),
+			base += size, i++) {
+		size = XFS_ATTR_SF_ENTSIZE(sfe);
+		if (sfe->namelen != args->name.len)
+			continue;
+		if (memcmp(sfe->nameval, args->name.name, args->name.len) != 0)
+			continue;
+		if (!xfs_attr_namesp_match(args->name.type, sfe->flags))
+			continue;
+		break;
+	}
+
+	if (sfep != NULL)
+		*sfep = sfe;
+
+	if (basep != NULL)
+		*basep = base;
+
+	if (i == end)
+		return -ENOATTR;
+	return -EEXIST;
+}
+
+/*
  * Add a name/value pair to the shortform attribute list.
  * Overflow from the inode has already been checked for.
  */
@@ -550,7 +597,7 @@  xfs_attr_shortform_add(xfs_da_args_t *args, int forkoff)
 {
 	xfs_attr_shortform_t *sf;
 	xfs_attr_sf_entry_t *sfe;
-	int i, offset, size;
+	int offset, size, error;
 	xfs_mount_t *mp;
 	xfs_inode_t *dp;
 	struct xfs_ifork *ifp;
@@ -564,18 +611,10 @@  xfs_attr_shortform_add(xfs_da_args_t *args, int forkoff)
 	ifp = dp->i_afp;
 	ASSERT(ifp->if_flags & XFS_IFINLINE);
 	sf = (xfs_attr_shortform_t *)ifp->if_u1.if_data;
-	sfe = &sf->list[0];
-	for (i = 0; i < sf->hdr.count; sfe = XFS_ATTR_SF_NEXTENTRY(sfe), i++) {
+	error = xfs_shortform_has_attr(args, &sfe, NULL);
 #ifdef DEBUG
-		if (sfe->namelen != args->name.len)
-			continue;
-		if (memcmp(args->name.name, sfe->nameval, args->name.len) != 0)
-			continue;
-		if (!xfs_attr_namesp_match(args->name.type, sfe->flags))
-			continue;
-		ASSERT(0);
+	ASSERT(error != -EEXIST);
 #endif
-	}
 
 	offset = (char *)sfe - (char *)sf;
 	size = XFS_ATTR_SF_ENTSIZE_BYNAME(args->name.len, args->valuelen);
@@ -620,33 +659,24 @@  xfs_attr_fork_remove(
 int
 xfs_attr_shortform_remove(xfs_da_args_t *args)
 {
-	xfs_attr_shortform_t *sf;
-	xfs_attr_sf_entry_t *sfe;
-	int base, size=0, end, totsize, i;
-	xfs_mount_t *mp;
-	xfs_inode_t *dp;
+	struct xfs_attr_shortform	*sf;
+	struct xfs_attr_sf_entry	*sfe;
+	int				base, size = 0, end, totsize;
+	struct xfs_mount		*mp;
+	struct xfs_inode		*dp;
+	int				error;
 
 	trace_xfs_attr_sf_remove(args);
 
 	dp = args->dp;
 	mp = dp->i_mount;
-	base = sizeof(xfs_attr_sf_hdr_t);
 	sf = (xfs_attr_shortform_t *)dp->i_afp->if_u1.if_data;
-	sfe = &sf->list[0];
 	end = sf->hdr.count;
-	for (i = 0; i < end; sfe = XFS_ATTR_SF_NEXTENTRY(sfe),
-					base += size, i++) {
-		size = XFS_ATTR_SF_ENTSIZE(sfe);
-		if (sfe->namelen != args->name.len)
-			continue;
-		if (memcmp(sfe->nameval, args->name.name, args->name.len) != 0)
-			continue;
-		if (!xfs_attr_namesp_match(args->name.type, sfe->flags))
-			continue;
-		break;
-	}
-	if (i == end)
-		return -ENOATTR;
+
+	error = xfs_shortform_has_attr(args, &sfe, &base);
+	if (error == -ENOATTR)
+		return error;
+	size = XFS_ATTR_SF_ENTSIZE(sfe);
 
 	/*
 	 * Fix up the attribute fork data, covering the hole
diff --git a/libxfs/xfs_attr_leaf.h b/libxfs/xfs_attr_leaf.h
index 536a290..58e9327 100644
--- a/libxfs/xfs_attr_leaf.h
+++ b/libxfs/xfs_attr_leaf.h
@@ -42,6 +42,8 @@  int	xfs_attr_shortform_getvalue(struct xfs_da_args *args);
 int	xfs_attr_shortform_to_leaf(struct xfs_da_args *args,
 			struct xfs_buf **leaf_bp);
 int	xfs_attr_shortform_remove(struct xfs_da_args *args);
+int	xfs_shortform_has_attr(struct xfs_da_args *args,
+			       struct xfs_attr_sf_entry **sfep, int *basep);
 int	xfs_attr_shortform_allfit(struct xfs_buf *bp, struct xfs_inode *dp);
 int	xfs_attr_shortform_bytesfit(struct xfs_inode *dp, int bytes);
 xfs_failaddr_t xfs_attr_shortform_verify(struct xfs_inode *ip);