ubifs: introduce Kconfig symbol for xattr support

Allow to disable extended attribute support.

This aids in reliability testing, especially since some xattr
related bugs have surfaced.

Also an embedded system might not need it, so this allows for a
slightly smaller kernel (about 4KiB).

Signed-off-by: Stefan Agner <stefan@agner.ch>
Signed-off-by: Richard Weinberger <richard@nod.at>

6 files changed, 29 insertions, 3 deletions

diff --git a/fs/ubifs/Kconfig b/fs/ubifs/Kconfig
index 83a961bf7280..bbc78549be4c 100644
--- a/fs/ubifs/Kconfig
+++ b/fs/ubifs/Kconfig
@@ -51,9 +51,20 @@ config UBIFS_ATIME_SUPPORT
 
           If unsure, say 'N'
 
+config UBIFS_FS_XATTR
+        bool "UBIFS XATTR support"
+        depends on UBIFS_FS
+        default y
+        help
+          Saying Y here includes support for extended attributes (xattrs).
+          Xattrs are name:value pairs associated with inodes by
+          the kernel or by users (see the attr(5) manual page).
+
+          If unsure, say Y.
+
 config UBIFS_FS_ENCRYPTION
         bool "UBIFS Encryption"
-        depends on UBIFS_FS && BLOCK
+        depends on UBIFS_FS && UBIFS_FS_XATTR && BLOCK
         select FS_ENCRYPTION
         default n
         help
@@ -64,7 +75,7 @@ config UBIFS_FS_ENCRYPTION
 
 config UBIFS_FS_SECURITY
         bool "UBIFS Security Labels"
-        depends on UBIFS_FS
+        depends on UBIFS_FS && UBIFS_FS_XATTR
         default y
         help
           Security labels provide an access control facility to support Linux
diff --git a/fs/ubifs/Makefile b/fs/ubifs/Makefile
index 9758f709c736..6197d7e539e4 100644
--- a/fs/ubifs/Makefile
+++ b/fs/ubifs/Makefile
@@ -4,6 +4,7 @@ obj-$(CONFIG_UBIFS_FS) += ubifs.o
 ubifs-y += shrinker.o journal.o file.o dir.o super.o sb.o io.o
 ubifs-y += tnc.o master.o scan.o replay.o log.o commit.o gc.o orphan.o
 ubifs-y += budget.o find.o tnc_commit.o compress.o lpt.o lprops.o
-ubifs-y += recovery.o ioctl.o lpt_commit.o tnc_misc.o xattr.o debug.o
+ubifs-y += recovery.o ioctl.o lpt_commit.o tnc_misc.o debug.o
 ubifs-y += misc.o
 ubifs-$(CONFIG_UBIFS_FS_ENCRYPTION) += crypto.o
+ubifs-$(CONFIG_UBIFS_FS_XATTR) += xattr.o
diff --git a/fs/ubifs/dir.c b/fs/ubifs/dir.c
index e8616040bffc..85aea556b709 100644
--- a/fs/ubifs/dir.c
+++ b/fs/ubifs/dir.c
@@ -1648,7 +1648,9 @@ const struct inode_operations ubifs_dir_inode_operations = {
         .rename      = ubifs_rename,
         .setattr     = ubifs_setattr,
         .getattr     = ubifs_getattr,
+#ifdef CONFIG_UBIFS_FS_XATTR
         .listxattr   = ubifs_listxattr,
+#endif
 #ifdef CONFIG_UBIFS_ATIME_SUPPORT
         .update_time = ubifs_update_time,
 #endif
diff --git a/fs/ubifs/file.c b/fs/ubifs/file.c
index 02fab5c322c7..745b3f810fb9 100644
--- a/fs/ubifs/file.c
+++ b/fs/ubifs/file.c
@@ -1653,7 +1653,9 @@ const struct address_space_operations ubifs_file_address_operations = {
 const struct inode_operations ubifs_file_inode_operations = {
         .setattr     = ubifs_setattr,
         .getattr     = ubifs_getattr,
+#ifdef CONFIG_UBIFS_FS_XATTR
         .listxattr   = ubifs_listxattr,
+#endif
 #ifdef CONFIG_UBIFS_ATIME_SUPPORT
         .update_time = ubifs_update_time,
 #endif
@@ -1663,7 +1665,9 @@ const struct inode_operations ubifs_symlink_inode_operations = {
         .get_link    = ubifs_get_link,
         .setattr     = ubifs_setattr,
         .getattr     = ubifs_getattr,
+#ifdef CONFIG_UBIFS_FS_XATTR
         .listxattr   = ubifs_listxattr,
+#endif
 #ifdef CONFIG_UBIFS_ATIME_SUPPORT
         .update_time = ubifs_update_time,
 #endif
diff --git a/fs/ubifs/super.c b/fs/ubifs/super.c
index c5466c70d620..564a131afc56 100644
--- a/fs/ubifs/super.c
+++ b/fs/ubifs/super.c
@@ -2053,7 +2053,9 @@ static int ubifs_fill_super(struct super_block *sb, void *data, int silent)
         if (c->max_inode_sz > MAX_LFS_FILESIZE)
                 sb->s_maxbytes = c->max_inode_sz = MAX_LFS_FILESIZE;
         sb->s_op = &ubifs_super_operations;
+#ifdef CONFIG_UBIFS_FS_XATTR
         sb->s_xattr = ubifs_xattr_handlers;
+#endif
 #ifdef CONFIG_UBIFS_FS_ENCRYPTION
         sb->s_cop = &ubifs_crypt_operations;
 #endif
diff --git a/fs/ubifs/ubifs.h b/fs/ubifs/ubifs.h
index 54fb6b1cd042..829308651a5e 100644
--- a/fs/ubifs/ubifs.h
+++ b/fs/ubifs/ubifs.h
@@ -1755,7 +1755,13 @@ int ubifs_xattr_set(struct inode *host, const char *name, const void *value,
                     size_t size, int flags, bool check_lock);
 ssize_t ubifs_xattr_get(struct inode *host, const char *name, void *buf,
                         size_t size);
+
+#ifdef CONFIG_UBIFS_FS_XATTR
 void ubifs_evict_xattr_inode(struct ubifs_info *c, ino_t xattr_inum);
+#else
+static inline void ubifs_evict_xattr_inode(struct ubifs_info *c,
+                                           ino_t xattr_inum) { }
+#endif
 
 #ifdef CONFIG_UBIFS_FS_SECURITY
 extern int ubifs_init_security(struct inode *dentry, struct inode *inode,