diff options
author | Tao Ma <tao.ma@oracle.com> | 2009-08-26 03:47:28 +0200 |
---|---|---|
committer | Joel Becker <joel.becker@oracle.com> | 2009-09-23 05:09:38 +0200 |
commit | 37f8a2bfaa8364dd3644cccee8824bb8f5e409a5 (patch) | |
tree | ab3083179c621c3e8d0be3980aaed96528f90599 /fs/ocfs2/file.c | |
parent | ocfs2: Integrate CoW in file write. (diff) | |
download | linux-37f8a2bfaa8364dd3644cccee8824bb8f5e409a5.tar.xz linux-37f8a2bfaa8364dd3644cccee8824bb8f5e409a5.zip |
ocfs2: CoW a reflinked cluster when it is truncated.
When we truncate a file to a specific size which resides in a reflinked
cluster, we need to CoW it since ocfs2_zero_range_for_truncate will
zero the space after the size(just another type of write).
So we add a "max_cpos" in ocfs2_refcount_cow so that it will stop when
it hit the max cluster offset.
Signed-off-by: Tao Ma <tao.ma@oracle.com>
Diffstat (limited to 'fs/ocfs2/file.c')
-rw-r--r-- | fs/ocfs2/file.c | 46 |
1 files changed, 45 insertions, 1 deletions
diff --git a/fs/ocfs2/file.c b/fs/ocfs2/file.c index 6ee20e82bcc5..75f5b81805b5 100644 --- a/fs/ocfs2/file.c +++ b/fs/ocfs2/file.c @@ -335,6 +335,39 @@ out: return ret; } +static int ocfs2_cow_file_pos(struct inode *inode, + struct buffer_head *fe_bh, + u64 offset) +{ + int status; + u32 phys, cpos = offset >> OCFS2_SB(inode->i_sb)->s_clustersize_bits; + unsigned int num_clusters = 0; + unsigned int ext_flags = 0; + + /* + * If the new offset is aligned to the range of the cluster, there is + * no space for ocfs2_zero_range_for_truncate to fill, so no need to + * CoW either. + */ + if ((offset & (OCFS2_SB(inode->i_sb)->s_clustersize - 1)) == 0) + return 0; + + status = ocfs2_get_clusters(inode, cpos, &phys, + &num_clusters, &ext_flags); + if (status) { + mlog_errno(status); + goto out; + } + + if (!(ext_flags & OCFS2_EXT_REFCOUNTED)) + goto out; + + return ocfs2_refcount_cow(inode, fe_bh, cpos, 1, cpos+1); + +out: + return status; +} + static int ocfs2_orphan_for_truncate(struct ocfs2_super *osb, struct inode *inode, struct buffer_head *fe_bh, @@ -347,6 +380,17 @@ static int ocfs2_orphan_for_truncate(struct ocfs2_super *osb, mlog_entry_void(); + /* + * We need to CoW the cluster contains the offset if it is reflinked + * since we will call ocfs2_zero_range_for_truncate later which will + * write "0" from offset to the end of the cluster. + */ + status = ocfs2_cow_file_pos(inode, fe_bh, new_i_size); + if (status) { + mlog_errno(status); + return status; + } + /* TODO: This needs to actually orphan the inode in this * transaction. */ @@ -1713,7 +1757,7 @@ static int ocfs2_prepare_inode_for_refcount(struct inode *inode, *meta_level = 1; - ret = ocfs2_refcount_cow(inode, di_bh, cpos, clusters); + ret = ocfs2_refcount_cow(inode, di_bh, cpos, clusters, UINT_MAX); if (ret) mlog_errno(ret); out: |