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author | Tristan Ye <tristan.ye@oracle.com> | 2010-12-07 14:35:07 +0800 |
---|---|---|
committer | Joel Becker <joel.becker@oracle.com> | 2010-12-09 15:36:48 -0800 |
commit | 39c99f12f15c8bf8257985d9b2a2548a03d18c00 (patch) | |
tree | 38f09ce41f6cbfd3a73b1dc66098ba3bf05e2d6a /fs/ocfs2/file.c | |
parent | 388c4bcb4e63e88fb1f312a2f5f9eb2623afcf5b (diff) | |
download | lwn-39c99f12f15c8bf8257985d9b2a2548a03d18c00.tar.gz lwn-39c99f12f15c8bf8257985d9b2a2548a03d18c00.zip |
Ocfs2: Teach 'coherency=full' O_DIRECT writes to correctly up_read i_alloc_sem.
Due to newly-introduced 'coherency=full' O_DIRECT writes also takes the EX
rw_lock like buffered writes did(rw_level == 1), it turns out messing the
usage of 'level' in ocfs2_dio_end_io() up, which caused i_alloc_sem being
failed to get up_read'd correctly.
This patch tries to teach ocfs2_dio_end_io to understand well on all locking
stuffs by explicitly introducing a new bit for i_alloc_sem in iocb's private
data, just like what we did for rw_lock.
Signed-off-by: Tristan Ye <tristan.ye@oracle.com>
Signed-off-by: Joel Becker <joel.becker@oracle.com>
Diffstat (limited to 'fs/ocfs2/file.c')
-rw-r--r-- | fs/ocfs2/file.c | 15 |
1 files changed, 13 insertions, 2 deletions
diff --git a/fs/ocfs2/file.c b/fs/ocfs2/file.c index 77b4c04a2809..f6cba566429d 100644 --- a/fs/ocfs2/file.c +++ b/fs/ocfs2/file.c @@ -2241,11 +2241,15 @@ static ssize_t ocfs2_file_aio_write(struct kiocb *iocb, mutex_lock(&inode->i_mutex); + ocfs2_iocb_clear_sem_locked(iocb); + relock: /* to match setattr's i_mutex -> i_alloc_sem -> rw_lock ordering */ if (direct_io) { down_read(&inode->i_alloc_sem); have_alloc_sem = 1; + /* communicate with ocfs2_dio_end_io */ + ocfs2_iocb_set_sem_locked(iocb); } /* @@ -2382,8 +2386,10 @@ out: ocfs2_rw_unlock(inode, rw_level); out_sems: - if (have_alloc_sem) + if (have_alloc_sem) { up_read(&inode->i_alloc_sem); + ocfs2_iocb_clear_sem_locked(iocb); + } mutex_unlock(&inode->i_mutex); @@ -2527,6 +2533,8 @@ static ssize_t ocfs2_file_aio_read(struct kiocb *iocb, goto bail; } + ocfs2_iocb_clear_sem_locked(iocb); + /* * buffered reads protect themselves in ->readpage(). O_DIRECT reads * need locks to protect pending reads from racing with truncate. @@ -2534,6 +2542,7 @@ static ssize_t ocfs2_file_aio_read(struct kiocb *iocb, if (filp->f_flags & O_DIRECT) { down_read(&inode->i_alloc_sem); have_alloc_sem = 1; + ocfs2_iocb_set_sem_locked(iocb); ret = ocfs2_rw_lock(inode, 0); if (ret < 0) { @@ -2575,8 +2584,10 @@ static ssize_t ocfs2_file_aio_read(struct kiocb *iocb, } bail: - if (have_alloc_sem) + if (have_alloc_sem) { up_read(&inode->i_alloc_sem); + ocfs2_iocb_clear_sem_locked(iocb); + } if (rw_level != -1) ocfs2_rw_unlock(inode, rw_level); mlog_exit(ret); |