[08/13] xfs: convert metadata inode lookup keys to use paths

Commit Message

Darrick J. Wong Jan. 1, 2020, 1:15 a.m. UTC

From: Darrick J. Wong <[e-mail]>

Convert the magic metadata inode lookup keys to use actual strings
for paths.

Signed-off-by: Darrick J. Wong <[e-mail]>
---
 fs/xfs/libxfs/xfs_imeta.c |   48 ++++++++++++++++++++++++---------------------
 fs/xfs/libxfs/xfs_imeta.h |   17 ++++++++++++++--
 2 files changed, 41 insertions(+), 24 deletions(-)

Patch

diff --git a/fs/xfs/libxfs/xfs_imeta.c b/fs/xfs/libxfs/xfs_imeta.c
index aadba5786d1c..ca62ef6255eb 100644
--- a/fs/xfs/libxfs/xfs_imeta.c
+++ b/fs/xfs/libxfs/xfs_imeta.c
@@ -47,26 +47,17 @@ 
  */
 
 /* Static metadata inode paths */
-
-const struct xfs_imeta_path XFS_IMETA_RTBITMAP = {
-	.bogus = 0,
-};
-
-const struct xfs_imeta_path XFS_IMETA_RTSUMMARY = {
-	.bogus = 1,
-};
-
-const struct xfs_imeta_path XFS_IMETA_USRQUOTA = {
-	.bogus = 2,
-};
-
-const struct xfs_imeta_path XFS_IMETA_GRPQUOTA = {
-	.bogus = 3,
-};
-
-const struct xfs_imeta_path XFS_IMETA_PRJQUOTA = {
-	.bogus = 4,
-};
+static const char *rtbitmap_path[]	= {"realtime", "0.bitmap"};
+static const char *rtsummary_path[]	= {"realtime", "0.summary"};
+static const char *usrquota_path[]	= {"quota", "user"};
+static const char *grpquota_path[]	= {"quota", "group"};
+static const char *prjquota_path[]	= {"quota", "project"};
+
+XFS_IMETA_DEFINE_PATH(XFS_IMETA_RTBITMAP,	rtbitmap_path);
+XFS_IMETA_DEFINE_PATH(XFS_IMETA_RTSUMMARY,	rtsummary_path);
+XFS_IMETA_DEFINE_PATH(XFS_IMETA_USRQUOTA,	usrquota_path);
+XFS_IMETA_DEFINE_PATH(XFS_IMETA_GRPQUOTA,	grpquota_path);
+XFS_IMETA_DEFINE_PATH(XFS_IMETA_PRJQUOTA,	prjquota_path);
 
 /* Are these two paths equal? */
 STATIC bool
@@ -74,7 +65,20 @@  xfs_imeta_path_compare(
 	const struct xfs_imeta_path	*a,
 	const struct xfs_imeta_path	*b)
 {
-	return a == b;
+	unsigned int			i;
+
+	if (a == b)
+		return true;
+
+	if (a->im_depth != b->im_depth)
+		return false;
+
+	for (i = 0; i < a->im_depth; i++)
+		if (a->im_path[i] != b->im_path[i] &&
+		    strcmp(a->im_path[i], b->im_path[i]))
+			return false;
+
+	return true;
 }
 
 /* Is this path ok? */
@@ -82,7 +86,7 @@  static inline bool
 xfs_imeta_path_check(
 	const struct xfs_imeta_path	*path)
 {
-	return true;
+	return path->im_depth <= XFS_IMETA_MAX_DEPTH;
 }
 
 /* Functions for storing and retrieving superblock inode values. */
diff --git a/fs/xfs/libxfs/xfs_imeta.h b/fs/xfs/libxfs/xfs_imeta.h
index 5321dba38bbe..6caf5b16f8d7 100644
--- a/fs/xfs/libxfs/xfs_imeta.h
+++ b/fs/xfs/libxfs/xfs_imeta.h
@@ -6,10 +6,23 @@ 
 #ifndef __XFS_IMETA_H__
 #define __XFS_IMETA_H__
 
+/* How deep can we nest metadata dirs? */
+#define XFS_IMETA_MAX_DEPTH	64
+
+/* Form an imeta path from a simple array of strings. */
+#define XFS_IMETA_DEFINE_PATH(name, path) \
+const struct xfs_imeta_path name = { \
+	.im_path = (path), \
+	.im_depth = ARRAY_SIZE(path), \
+}
+
 /* Key for looking up metadata inodes. */
 struct xfs_imeta_path {
-	/* Temporary: integer to keep the static imeta definitions unique */
-	int		bogus;
+	/* Array of string pointers. */
+	const char	**im_path;
+
+	/* Number of strings in path. */
+	unsigned int	im_depth;
 };
 
 /* Cleanup widget for metadata inode creation and deletion. */