linux/fs/ecryptfs
Christoph Lameter eebd2aa355 Pagecache zeroing: zero_user_segment, zero_user_segments and zero_user
Simplify page cache zeroing of segments of pages through 3 functions

zero_user_segments(page, start1, end1, start2, end2)

        Zeros two segments of the page. It takes the position where to
        start and end the zeroing which avoids length calculations and
	makes code clearer.

zero_user_segment(page, start, end)

        Same for a single segment.

zero_user(page, start, length)

        Length variant for the case where we know the length.

We remove the zero_user_page macro. Issues:

1. Its a macro. Inline functions are preferable.

2. The KM_USER0 macro is only defined for HIGHMEM.

   Having to treat this special case everywhere makes the
   code needlessly complex. The parameter for zeroing is always
   KM_USER0 except in one single case that we open code.

Avoiding KM_USER0 makes a lot of code not having to be dealing
with the special casing for HIGHMEM anymore. Dealing with
kmap is only necessary for HIGHMEM configurations. In those
configurations we use KM_USER0 like we do for a series of other
functions defined in highmem.h.

Since KM_USER0 is depends on HIGHMEM the existing zero_user_page
function could not be a macro. zero_user_* functions introduced
here can be be inline because that constant is not used when these
functions are called.

Also extract the flushing of the caches to be outside of the kmap.

[akpm@linux-foundation.org: fix nfs and ntfs build]
[akpm@linux-foundation.org: fix ntfs build some more]
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Cc: Steven French <sfrench@us.ibm.com>
Cc: Michael Halcrow <mhalcrow@us.ibm.com>
Cc: <linux-ext4@vger.kernel.org>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Anton Altaparmakov <aia21@cantab.net>
Cc: Mark Fasheh <mark.fasheh@oracle.com>
Cc: David Chinner <dgc@sgi.com>
Cc: Michael Halcrow <mhalcrow@us.ibm.com>
Cc: Steven French <sfrench@us.ibm.com>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05 09:44:13 -08:00
..
crypto.c ecryptfs: fix unlocking in error paths 2007-12-23 12:54:37 -08:00
debug.c eCryptfs: update comment and debug statement 2007-10-16 09:43:11 -07:00
dentry.c [PATCH] eCryptfs: fix possible NULL ptr deref in ecryptfs_d_release() 2007-03-16 19:25:05 -07:00
ecryptfs_kernel.h ecryptfs: clean up page flag handling 2007-10-16 09:43:12 -07:00
file.c eCryptfs: remove unused functions and kmem_cache 2007-10-16 09:43:12 -07:00
inode.c eCryptfs: fix dentry handling on create error, unlink, and inode destroy 2008-01-08 16:10:36 -08:00
keystore.c ecryptfs: initialize new auth_tokens before teardown 2007-12-17 19:28:15 -08:00
main.c Kobject: convert fs/* from kobject_unregister() to kobject_put() 2008-01-24 20:40:40 -08:00
Makefile eCryptfs: read_write.c routines 2007-10-16 09:43:12 -07:00
messaging.c ecryptfs: fix unlocking in error paths 2007-12-23 12:54:37 -08:00
mmap.c Pagecache zeroing: zero_user_segment, zero_user_segments and zero_user 2008-02-05 09:44:13 -08:00
netlink.c [NETNS]: Consolidate kernel netlink socket destruction. 2008-01-28 15:08:07 -08:00
read_write.c ecryptfs: fix fsx data corruption problems 2007-12-17 19:28:17 -08:00
super.c eCryptfs: fix dentry handling on create error, unlink, and inode destroy 2008-01-08 16:10:36 -08:00