[PATCH] fs.h: ifdef security fields

[assuming BSD security levels are deleted]
The only user of i_security, f_security, s_security fields is SELinux,
however, quite a few security modules are trying to get into kernel.
So, wrap them under CONFIG_SECURITY. Adding config option for each
security field is likely an overkill.

Following Stephen Smalley's suggestion, i_security initialization is
moved to security_inode_alloc() to not clutter core code with ifdefs
and make alloc_inode() codepath tiny little bit smaller and faster.

The user of (highly greppable) struct fown_struct::security field is
still to be found. I've checked every "fown_struct" and every "f_owner"
occurence. Additionally it's removal doesn't break i386 allmodconfig
build.

struct inode, struct file, struct super_block, struct fown_struct
become smaller.

P.S. Combined with two reiserfs inode shrinking patches sent to
linux-fsdevel, I can finally suck 12 reiserfs inodes into one page.

		/proc/slabinfo

	-ext2_inode_cache	388	10
	+ext2_inode_cache	384	10
	-inode_cache		280	14
	+inode_cache		276	14
	-proc_inode_cache	296	13
	+proc_inode_cache	292	13
	-reiser_inode_cache	336	11
	+reiser_inode_cache	332	12 <=
	-shmem_inode_cache	372	10
	+shmem_inode_cache	368	10

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 0 insertions, 1 deletions

diff --git a/fs/inode.c b/fs/inode.c
index f5c04dd9ae8..abf77471e6c 100644
--- a/fs/inode.c
+++ b/fs/inode.c
@@ -133,7 +133,6 @@ static struct inode *alloc_inode(struct super_block *sb)
                 inode->i_bdev = NULL;
                 inode->i_cdev = NULL;
                 inode->i_rdev = 0;
-                inode->i_security = NULL;
                 inode->dirtied_when = 0;
                 if (security_inode_alloc(inode)) {
                         if (inode->i_sb->s_op->destroy_inode)