Wang Shilong
2014-Jul-17 03:44 UTC
[PATCH 1/6] Btrfs: fix wrong skipping compression for an inode
If a file's compression ratios is bad, we will set NOCOMPRESS
flag for it, and it will skip compression for that inode next time.
However, if we remount fs to COMPRESS_FORCE, it still should try
if we could compress pages for that inode, this patch fix wrong
check for this problem.
Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com>
---
fs/btrfs/inode.c | 25 ++++++++++++++++++++-----
1 file changed, 20 insertions(+), 5 deletions(-)
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index a58f31c..20798f8 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -348,6 +348,23 @@ static noinline int add_async_extent(struct async_cow *cow,
return 0;
}
+static inline int inode_need_compress(struct inode *inode)
+{
+ struct btrfs_root *root = BTRFS_I(inode)->root;
+
+ /* force compress */
+ if (btrfs_test_opt(root, FORCE_COMPRESS))
+ return 1;
+ /* bad compression ratios */
+ if (BTRFS_I(inode)->flags & BTRFS_INODE_NOCOMPRESS)
+ return 0;
+ if (btrfs_test_opt(root, COMPRESS) ||
+ BTRFS_I(inode)->flags & BTRFS_INODE_COMPRESS ||
+ BTRFS_I(inode)->force_compress)
+ return 1;
+ return 0;
+}
+
/*
* we create compressed extents in two phases. The first
* phase compresses a range of pages that have already been
@@ -444,10 +461,7 @@ again:
* inode has not been flagged as nocompress. This flag can
* change at any time if we discover bad compression ratios.
*/
- if (!(BTRFS_I(inode)->flags & BTRFS_INODE_NOCOMPRESS) &&
- (btrfs_test_opt(root, COMPRESS) ||
- (BTRFS_I(inode)->force_compress) ||
- (BTRFS_I(inode)->flags & BTRFS_INODE_COMPRESS))) {
+ if (inode_need_compress(inode)) {
WARN_ON(pages);
pages = kzalloc(sizeof(struct page *) * nr_pages, GFP_NOFS);
if (!pages) {
@@ -1076,7 +1090,8 @@ static int cow_file_range_async(struct inode *inode,
struct page *locked_page,
async_cow->locked_page = locked_page;
async_cow->start = start;
- if (BTRFS_I(inode)->flags & BTRFS_INODE_NOCOMPRESS)
+ if (BTRFS_I(inode)->flags & BTRFS_INODE_NOCOMPRESS &&
+ !btrfs_test_opt(root, FORCE_COMPRESS))
cur_end = end;
else
cur_end = min(end, start + 512 * 1024 - 1);
--
1.8.2.1
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