[PATCH V8 6/8] btrfs: add cleancache support This sixth patch of eight in this cleancache series "opts-in" cleancache for btrfs. Filesystems must explicitly enable cleancache by calling cleancache_init_fs anytime an instance of the filesystem is mounted. Btrfs uses its own readpage which must be hooked, but all other cleancache hooks are in the VFS layer including the matching cleancache_flush_fs hook which must be called on unmount.
Details and a FAQ can be found in Documentation/vm/cleancache.txt [v6-v8: no changes] [v5: [email protected]: simplify init hook and any future fs init changes] Signed-off-by: Dan Magenheimer <[email protected]> Signed-off-by: Chris Mason <[email protected]> Reviewed-by: Jeremy Fitzhardinge <[email protected]> Reviewed-by: Konrad Rzeszutek Wilk <[email protected]> Cc: Andrew Morton <[email protected]> Cc: Al Viro <[email protected]> Cc: Matthew Wilcox <[email protected]> Cc: Nick Piggin <[email protected]> Cc: Mel Gorman <[email protected]> Cc: Rik Van Riel <[email protected]> Cc: Jan Beulich <[email protected]> Cc: Andreas Dilger <[email protected]> Cc: Ted Ts'o <[email protected]> Cc: Mark Fasheh <[email protected]> Cc: Joel Becker <[email protected]> Cc: Nitin Gupta <[email protected]> --- Diffstat: fs/btrfs/extent_io.c | 9 +++++++++ fs/btrfs/super.c | 2 ++ 2 files changed, 11 insertions(+) --- linux-2.6.39-rc3/fs/btrfs/super.c 2011-04-11 18:21:51.000000000 -0600 +++ linux-2.6.39-rc3-cleancache/fs/btrfs/super.c 2011-04-13 17:10:46.357852791 -0600 @@ -39,6 +39,7 @@ #include <linux/miscdevice.h> #include <linux/magic.h> #include <linux/slab.h> +#include <linux/cleancache.h> #include "compat.h" #include "ctree.h" #include "disk-io.h" @@ -610,6 +611,7 @@ static int btrfs_fill_super(struct super sb->s_root = root_dentry; save_mount_options(sb, data); + cleancache_init_fs(sb); return 0; fail_close: --- linux-2.6.39-rc3/fs/btrfs/extent_io.c 2011-04-11 18:21:51.000000000 -0600 +++ linux-2.6.39-rc3-cleancache/fs/btrfs/extent_io.c 2011-04-13 17:10:46.368921914 -0600 @@ -10,6 +10,7 @@ #include <linux/swap.h> #include <linux/writeback.h> #include <linux/pagevec.h> +#include <linux/cleancache.h> #include "extent_io.h" #include "extent_map.h" #include "compat.h" @@ -1990,6 +1991,13 @@ static int __extent_read_full_page(struc set_page_extent_mapped(page); + if (!PageUptodate(page)) { + if (cleancache_get_page(page) == 0) { + BUG_ON(blocksize != PAGE_SIZE); + goto out; + } + } + end = page_end; while (1) { lock_extent(tree, start, end, GFP_NOFS); @@ -2117,6 +2125,7 @@ static int __extent_read_full_page(struc cur = cur + iosize; page_offset += iosize; } +out: if (!nr) { if (!PageError(page)) SetPageUptodate(page); -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
