Merge tag 'pptrs-6.10_2024-04-23' of https://git.kernel.org/pub/scm/linux/kernel/git/djwong/xfs-linux into xfs-6.10-mergeC

xfs: Parent Pointers

This is the latest parent pointer attributes for xfs.  The goal of this
patch set is to add a parent pointer attribute to each inode.  The
attribute name containing the parent inode, generation, and directory
offset, while the  attribute value contains the file name.  This feature
will enable future optimizations for online scrub, shrink, nfs handles,
verity, or any other feature that could make use of quickly deriving an
inodes path from the mount point.

Directory parent pointers are stored as namespaced extended attributes
of a file.  Because parent pointers are an indivisible tuple of
(dirent_name, parent_ino, parent_gen) we cannot use the usual attr name
lookup functions to find a parent pointer.  This is solvable by
introducing a new lookup mode that checks both the name and the value of
the xattr.

Therefore, introduce this new name-value lookup mode that's gated on the
XFS_ATTR_PARENT namespace.  This requires the introduction of new
opcodes for the extended attribute update log intent items, which
actually means that parent pointers (itself an INCOMPAT feature) does
not depend on the LOGGED_XATTRS log incompat feature bit.

To reduce collisions on the dirent names of parent pointers, introduce a
new attr hash mode that is the dir2 namehash of the dirent name xor'd
with the parent inode number.

Signed-off-by: Darrick J. Wong <[email protected]>
Signed-off-by: Chandan Babu R <[email protected]>

* tag 'pptrs-6.10_2024-04-23' of https://git.kernel.org/pub/scm/linux/kernel/git/djwong/xfs-linux:
  xfs: enable parent pointers
  xfs: drop compatibility minimum log size computations for reflink
  xfs: fix unit conversion error in xfs_log_calc_max_attrsetm_res
  xfs: add a incompat feature bit for parent pointers
  xfs: don't remove the attr fork when parent pointers are enabled
  xfs: add parent pointer ioctls
  xfs: split out handle management helpers a bit
  xfs: move handle ioctl code to xfs_handle.c
  xfs: pass the attr value to put_listent when possible
  xfs: don't return XFS_ATTR_PARENT attributes via listxattr
  xfs: Add parent pointers to xfs_cross_rename
  xfs: Add parent pointers to rename
  xfs: remove parent pointers in unlink
  xfs: add parent attributes to symlink
  xfs: add parent attributes to link
  xfs: parent pointer attribute creation
  xfs: create a hashname function for parent pointers
  xfs: extend transaction reservations for parent attributes
  xfs: add parent pointer validator functions
  xfs: Expose init_xattrs in xfs_create_tmpfile
  xfs: record inode generation in xattr update log intent items
  xfs: create attr log item opcodes and formats for parent pointers
  xfs: refactor xfs_is_using_logged_xattrs checks in attr item recovery
  xfs: allow xattr matching on name and value for parent pointers
  xfs: define parent pointer ondisk extended attribute format
  xfs: add parent pointer support to attribute code
  xfs: create a separate hashname function for extended attributes
  xfs: move xfs_attr_defer_add to xfs_attr_item.c
  xfs: check the flags earlier in xfs_attr_match
  xfs: rearrange xfs_attr_match parameters

Author: Chandan Babu R

fs/xfs/Makefile

@@ -42,6 +42,7 @@ xfs-y				+= $(addprefix libxfs/, \
 				   xfs_inode_buf.o \
 				   xfs_log_rlimit.o \
 				   xfs_ag_resv.o \
+				   xfs_parent.o \
 				   xfs_rmap.o \
 				   xfs_rmap_btree.o \
 				   xfs_refcount.o \
@@ -50,6 +51,7 @@ xfs-y				+= $(addprefix libxfs/, \
 				   xfs_symlink_remote.o \
 				   xfs_trans_inode.o \
 				   xfs_trans_resv.o \
+				   xfs_trans_space.o \
 				   xfs_types.o \
 				   )
 # xfs_rtbitmap is shared with libxfs
@@ -76,6 +78,7 @@ xfs-y				+= xfs_aops.o \
 				   xfs_fsmap.o \
 				   xfs_fsops.o \
 				   xfs_globals.o \
+				   xfs_handle.o \
 				   xfs_health.o \
 				   xfs_icache.o \
 				   xfs_ioctl.o \

fs/xfs/libxfs/xfs_attr.c

@@ -26,6 +26,7 @@
 #include "xfs_trace.h"
 #include "xfs_attr_item.h"
 #include "xfs_xattr.h"
+#include "xfs_parent.h"
 
 struct kmem_cache		*xfs_attr_intent_cache;
 
@@ -280,7 +281,7 @@ xfs_attr_get(
 		args->owner = args->dp->i_ino;
 	args->geo = args->dp->i_mount->m_attr_geo;
 	args->whichfork = XFS_ATTR_FORK;
-	args->hashval = xfs_da_hashname(args->name, args->namelen);
+	xfs_attr_sethash(args);
 
 	/* Entirely possible to look up a name which doesn't exist */
 	args->op_flags = XFS_DA_OP_OKNOENT;
@@ -415,6 +416,50 @@ xfs_attr_sf_addname(
 	return error;
 }
 
+/* Compute the hash value for a user/root/secure extended attribute */
+xfs_dahash_t
+xfs_attr_hashname(
+	const uint8_t		*name,
+	int			namelen)
+{
+	return xfs_da_hashname(name, namelen);
+}
+
+/* Compute the hash value for any extended attribute from any namespace. */
+xfs_dahash_t
+xfs_attr_hashval(
+	struct xfs_mount	*mp,
+	unsigned int		attr_flags,
+	const uint8_t		*name,
+	int			namelen,
+	const void		*value,
+	int			valuelen)
+{
+	ASSERT(xfs_attr_check_namespace(attr_flags));
+
+	if (attr_flags & XFS_ATTR_PARENT)
+		return xfs_parent_hashattr(mp, name, namelen, value, valuelen);
+
+	return xfs_attr_hashname(name, namelen);
+}
+
+/*
+ * PPTR_REPLACE operations require the caller to set the old and new names and
+ * values explicitly.  Update the canonical fields to the new name and value
+ * here now that the removal phase has finished.
+ */
+static void
+xfs_attr_update_pptr_replace_args(
+	struct xfs_da_args	*args)
+{
+	ASSERT(args->new_namelen > 0);
+	args->name = args->new_name;
+	args->namelen = args->new_namelen;
+	args->value = args->new_value;
+	args->valuelen = args->new_valuelen;
+	xfs_attr_sethash(args);
+}
+
 /*
  * Handle the state change on completion of a multi-state attr operation.
  *
@@ -435,6 +480,8 @@ xfs_attr_complete_op(
 
 	if (!(args->op_flags & XFS_DA_OP_REPLACE))
 		replace_state = XFS_DAS_DONE;
+	else if (xfs_attr_intent_op(attr) == XFS_ATTRI_OP_FLAGS_PPTR_REPLACE)
+		xfs_attr_update_pptr_replace_args(args);
 
 	args->op_flags &= ~XFS_DA_OP_REPLACE;
 	args->attr_filter &= ~XFS_ATTR_INCOMPLETE;
@@ -901,37 +948,6 @@ xfs_attr_lookup(
 	return error;
 }
 
-static void
-xfs_attr_defer_add(
-	struct xfs_da_args	*args,
-	unsigned int		op_flags)
-{
-
-	struct xfs_attr_intent	*new;
-
-	new = kmem_cache_zalloc(xfs_attr_intent_cache,
-			GFP_KERNEL | __GFP_NOFAIL);
-	new->xattri_op_flags = op_flags;
-	new->xattri_da_args = args;
-
-	switch (op_flags) {
-	case XFS_ATTRI_OP_FLAGS_SET:
-		new->xattri_dela_state = xfs_attr_init_add_state(args);
-		break;
-	case XFS_ATTRI_OP_FLAGS_REPLACE:
-		new->xattri_dela_state = xfs_attr_init_replace_state(args);
-		break;
-	case XFS_ATTRI_OP_FLAGS_REMOVE:
-		new->xattri_dela_state = xfs_attr_init_remove_state(args);
-		break;
-	default:
-		ASSERT(0);
-	}
-
-	xfs_defer_add(args->trans, &new->xattri_list, &xfs_attr_defer_type);
-	trace_xfs_attr_defer_add(new->xattri_dela_state, args->dp);
-}
-
 int
 xfs_attr_set(
 	struct xfs_da_args	*args,
@@ -956,7 +972,7 @@ xfs_attr_set(
 		args->owner = args->dp->i_ino;
 	args->geo = mp->m_attr_geo;
 	args->whichfork = XFS_ATTR_FORK;
-	args->hashval = xfs_da_hashname(args->name, args->namelen);
+	xfs_attr_sethash(args);
 
 	/*
 	 * We have no control over the attribute names that userspace passes us
@@ -1021,14 +1037,14 @@ xfs_attr_set(
 	case -EEXIST:
 		if (op == XFS_ATTRUPDATE_REMOVE) {
 			/* if no value, we are performing a remove operation */
-			xfs_attr_defer_add(args, XFS_ATTRI_OP_FLAGS_REMOVE);
+			xfs_attr_defer_add(args, XFS_ATTR_DEFER_REMOVE);
 			break;
 		}
 
 		/* Pure create fails if the attr already exists */
 		if (op == XFS_ATTRUPDATE_CREATE)
 			goto out_trans_cancel;
-		xfs_attr_defer_add(args, XFS_ATTRI_OP_FLAGS_REPLACE);
+		xfs_attr_defer_add(args, XFS_ATTR_DEFER_REPLACE);
 		break;
 	case -ENOATTR:
 		/* Can't remove what isn't there. */
@@ -1038,7 +1054,7 @@ xfs_attr_set(
 		/* Pure replace fails if no existing attr to replace. */
 		if (op == XFS_ATTRUPDATE_REPLACE)
 			goto out_trans_cancel;
-		xfs_attr_defer_add(args, XFS_ATTRI_OP_FLAGS_SET);
+		xfs_attr_defer_add(args, XFS_ATTR_DEFER_SET);
 		break;
 	default:
 		goto out_trans_cancel;
@@ -1556,6 +1572,10 @@ xfs_attr_namecheck(
 	if (length >= MAXNAMELEN)
 		return false;
 
+	/* Parent pointers have their own validation. */
+	if (attr_flags & XFS_ATTR_PARENT)
+		return xfs_parent_namecheck(attr_flags, name, length);
+
 	/* There shouldn't be any nulls here */
 	return !memchr(name, 0, length);
 }

fs/xfs/libxfs/xfs_attr.h

@@ -47,8 +47,9 @@ struct xfs_attrlist_cursor_kern {
 
 
 /* void; state communicated via *context */
-typedef void (*put_listent_func_t)(struct xfs_attr_list_context *, int,
-			      unsigned char *, int, int);
+typedef void (*put_listent_func_t)(struct xfs_attr_list_context *context,
+		int flags, unsigned char *name, int namelen, void *value,
+		int valuelen);
 
 struct xfs_attr_list_context {
 	struct xfs_trans	*tp;
@@ -510,8 +511,8 @@ struct xfs_attr_intent {
 	struct xfs_da_args		*xattri_da_args;
 
 	/*
-	 * Shared buffer containing the attr name and value so that the logging
-	 * code can share large memory buffers between log items.
+	 * Shared buffer containing the attr name, new name, and value so that
+	 * the logging code can share large memory buffers between log items.
 	 */
 	struct xfs_attri_log_nameval	*xattri_nameval;
 
@@ -628,6 +629,20 @@ xfs_attr_init_replace_state(struct xfs_da_args *args)
 	return xfs_attr_init_add_state(args);
 }
 
+xfs_dahash_t xfs_attr_hashname(const uint8_t *name, int namelen);
+
+xfs_dahash_t xfs_attr_hashval(struct xfs_mount *mp, unsigned int attr_flags,
+		const uint8_t *name, int namelen, const void *value,
+		int valuelen);
+
+/* Set the hash value for any extended attribute from any namespace. */
+static inline void xfs_attr_sethash(struct xfs_da_args *args)
+{
+	args->hashval = xfs_attr_hashval(args->dp->i_mount, args->attr_filter,
+					 args->name, args->namelen,
+					 args->value, args->valuelen);
+}
+
 extern struct kmem_cache *xfs_attr_intent_cache;
 int __init xfs_attr_intent_init_cache(void);
 void xfs_attr_intent_destroy_cache(void);

fs/xfs/libxfs/xfs_attr_leaf.c

@@ -507,28 +507,57 @@ xfs_attr3_leaf_read(
  * INCOMPLETE flag will not be set in attr->attr_filter, but rather
  * XFS_DA_OP_RECOVERY will be set in args->op_flags.
  */
+static inline unsigned int xfs_attr_match_mask(const struct xfs_da_args *args)
+{
+	if (args->op_flags & XFS_DA_OP_RECOVERY)
+		return XFS_ATTR_NSP_ONDISK_MASK;
+	return XFS_ATTR_NSP_ONDISK_MASK | XFS_ATTR_INCOMPLETE;
+}
+
+static inline bool
+xfs_attr_parent_match(
+	const struct xfs_da_args	*args,
+	const void			*value,
+	unsigned int			valuelen)
+{
+	ASSERT(args->value != NULL);
+
+	/* Parent pointers do not use remote values */
+	if (!value)
+		return false;
+
+	/*
+	 * The only value we support is a parent rec.  However, we'll accept
+	 * any valuelen so that offline repair can delete ATTR_PARENT values
+	 * that are not parent pointers.
+	 */
+	if (valuelen != args->valuelen)
+		return false;
+
+	return memcmp(args->value, value, valuelen) == 0;
+}
+
 static bool
 xfs_attr_match(
 	struct xfs_da_args	*args,
-	uint8_t			namelen,
-	unsigned char		*name,
-	int			flags)
+	unsigned int		attr_flags,
+	const unsigned char	*name,
+	unsigned int		namelen,
+	const void		*value,
+	unsigned int		valuelen)
 {
+	unsigned int		mask = xfs_attr_match_mask(args);
 
 	if (args->namelen != namelen)
 		return false;
+	if ((args->attr_filter & mask) != (attr_flags & mask))
+		return false;
 	if (memcmp(args->name, name, namelen) != 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))
-		return true;
+	if (attr_flags & XFS_ATTR_PARENT)
+		return xfs_attr_parent_match(args, value, valuelen);
 
-	/* All remaining matches need to be filtered by INCOMPLETE state. */
-	if (args->attr_filter !=
-	    (flags & (XFS_ATTR_NSP_ONDISK_MASK | XFS_ATTR_INCOMPLETE)))
-		return false;
 	return true;
 }
 
@@ -538,6 +567,13 @@ xfs_attr_copy_value(
 	unsigned char		*value,
 	int			valuelen)
 {
+	/*
+	 * Parent pointer lookups require the caller to specify the name and
+	 * value, so don't copy anything.
+	 */
+	if (args->attr_filter & XFS_ATTR_PARENT)
+		return 0;
+
 	/*
 	 * No copy if all we have to do is get the length
 	 */
@@ -746,8 +782,9 @@ xfs_attr_sf_findname(
 	for (sfe = xfs_attr_sf_firstentry(sf);
 	     sfe < xfs_attr_sf_endptr(sf);
 	     sfe = xfs_attr_sf_nextentry(sfe)) {
-		if (xfs_attr_match(args, sfe->namelen, sfe->nameval,
-				sfe->flags))
+		if (xfs_attr_match(args, sfe->flags, sfe->nameval,
+				sfe->namelen, &sfe->nameval[sfe->namelen],
+				sfe->valuelen))
 			return sfe;
 	}
 
@@ -854,7 +891,8 @@ xfs_attr_sf_removename(
 	 */
 	if (totsize == sizeof(struct xfs_attr_sf_hdr) && xfs_has_attr2(mp) &&
 	    (dp->i_df.if_format != XFS_DINODE_FMT_BTREE) &&
-	    !(args->op_flags & (XFS_DA_OP_ADDNAME | XFS_DA_OP_REPLACE))) {
+	    !(args->op_flags & (XFS_DA_OP_ADDNAME | XFS_DA_OP_REPLACE)) &&
+	    !xfs_has_parent(mp)) {
 		xfs_attr_fork_remove(dp, args->trans);
 	} else {
 		xfs_idata_realloc(dp, -size, XFS_ATTR_FORK);
@@ -863,7 +901,8 @@ xfs_attr_sf_removename(
 		ASSERT(totsize > sizeof(struct xfs_attr_sf_hdr) ||
 				(args->op_flags & XFS_DA_OP_ADDNAME) ||
 				!xfs_has_attr2(mp) ||
-				dp->i_df.if_format == XFS_DINODE_FMT_BTREE);
+				dp->i_df.if_format == XFS_DINODE_FMT_BTREE ||
+				xfs_has_parent(mp));
 		xfs_trans_log_inode(args->trans, dp,
 					XFS_ILOG_CORE | XFS_ILOG_ADATA);
 	}
@@ -947,14 +986,13 @@ xfs_attr_shortform_to_leaf(
 		nargs.namelen = sfe->namelen;
 		nargs.value = &sfe->nameval[nargs.namelen];
 		nargs.valuelen = sfe->valuelen;
-		nargs.hashval = xfs_da_hashname(sfe->nameval,
-						sfe->namelen);
 		nargs.attr_filter = sfe->flags & XFS_ATTR_NSP_ONDISK_MASK;
 		if (!xfs_attr_check_namespace(sfe->flags)) {
 			xfs_da_mark_sick(args);
 			error = -EFSCORRUPTED;
 			goto out;
 		}
+		xfs_attr_sethash(&nargs);
 		error = xfs_attr3_leaf_lookup_int(bp, &nargs); /* set a->index */
 		ASSERT(error == -ENOATTR);
 		error = xfs_attr3_leaf_add(bp, &nargs);
@@ -2443,18 +2481,23 @@ 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))
+			if (!xfs_attr_match(args, entry->flags,
+					name_loc->nameval, name_loc->namelen,
+					&name_loc->nameval[name_loc->namelen],
+					be16_to_cpu(name_loc->valuelen)))
 				continue;
 			args->index = probe;
 			return -EEXIST;
 		} else {
+			unsigned int	valuelen;
+
 			name_rmt = xfs_attr3_leaf_name_remote(leaf, probe);
-			if (!xfs_attr_match(args, name_rmt->namelen,
-					name_rmt->name, entry->flags))
+			valuelen = be32_to_cpu(name_rmt->valuelen);
+			if (!xfs_attr_match(args, entry->flags, name_rmt->name,
+					name_rmt->namelen, NULL, valuelen))
 				continue;
 			args->index = probe;
-			args->rmtvaluelen = be32_to_cpu(name_rmt->valuelen);
+			args->rmtvaluelen = valuelen;
 			args->rmtblkno = be32_to_cpu(name_rmt->valueblk);
 			args->rmtblkcnt = xfs_attr3_rmt_blocks(
 							args->dp->i_mount,

fs/xfs/libxfs/xfs_attr_sf.h

@@ -16,6 +16,7 @@ typedef struct xfs_attr_sf_sort {
 	uint8_t		flags;		/* flags bits (see xfs_attr_leaf.h) */
 	xfs_dahash_t	hash;		/* this entry's hash value */
 	unsigned char	*name;		/* name value, pointer into buffer */
+	void		*value;
 } xfs_attr_sf_sort_t;
 
 #define XFS_ATTR_SF_ENTSIZE_MAX			/* max space for name&value */ \