ext2/3 updates for 2.5.44 (4/11): mbcache infrastructure for xattrs

# The following is the BitKeeper ChangeSet Log
# --------------------------------------------
# 02/10/20 [email protected] 1.813
# Port of the 0.8.50 xattr-mbcache patch to 2.5. (Shrinker API, hch cleanups) # (now uses struct block_device * to index devices, and uses hash.h for hash function) #
# This patch creates a meta block cache which is utilized by the ext3 and

# ext2 extended attribute patch (patches 2 and 3, respectively).  This
# cache allows directory blocks to be indexed by multiple keys.  In the
# case of the extended attribute patches, it is used to look up blocks by
# both the block number and by the hash of the extended attributes.  This
# is extremely important to allow the sharing of acl's when stored as
# extended attributes.  Otherwise every single file would require its own,
# separate, one block overhead to store then ACL, even though there might
# be a large number of files that have the same ACL.
# --------------------------------------------
#
# fs/Config.in            |   11 
# fs/Makefile             |    4 
# fs/mbcache.c            |  702 ++++++++++++++++++++++++++++++++++++++++++++++++
# include/linux/mbcache.h |   72 ++++
# 4 files changed, 788 insertions(+), 1 deletion(-)
#
diff -Nru a/fs/Config.in b/fs/Config.in
--- a/fs/Config.in	Sun Oct 20 04:40:53 2002
+++ b/fs/Config.in	Sun Oct 20 04:40:53 2002
@@ -182,6 +182,17 @@
    define_tristate CONFIG_ZISOFS_FS n
 fi

+# Meta block cache for Extended Attributes (ext2/ext3)
+if [ "$CONFIG_EXT2_FS_XATTR" = "y" -o "$CONFIG_EXT3_FS_XATTR" = "y" ]; then
+ if [ "$CONFIG_EXT2_FS" = "y" -o "$CONFIG_EXT3_FS" = "y" ]; then
+ define_tristate CONFIG_FS_MBCACHE y
+ else
+ if [ "$CONFIG_EXT2_FS" = "m" -o "$CONFIG_EXT3_FS" = "m" ]; then
+ define_tristate CONFIG_FS_MBCACHE m
+ fi
+ fi
+fi
+
mainmenu_option next_comment
comment 'Partition Types'
source fs/partitions/Config.in

diff -Nru a/fs/Makefile b/fs/Makefile
@@ -6,7 +6,7 @@
 # 
 
 export-objs :=	open.o dcache.o buffer.o bio.o inode.o dquot.o mpage.o aio.o \
-                fcntl.o read_write.o dcookies.o
+                fcntl.o read_write.o dcookies.o mbcache.o
 
 obj-y :=	open.o read_write.o devices.o file_table.o buffer.o \
 		bio.o super.o block_dev.o char_dev.o stat.o exec.o pipe.o \

@@ -29,6 +29,8 @@
 obj-y				+= binfmt_script.o
 
 obj-$(CONFIG_BINFMT_ELF)	+= binfmt_elf.o
+
+obj-$(CONFIG_FS_MBCACHE)	+= mbcache.o
 
 obj-$(CONFIG_QUOTA)		+= dquot.o
 obj-$(CONFIG_QFMT_V1)		+= quota_v1.o