diff options
| -rw-r--r-- | fs/direct-io.c | 25 | ||||
| -rw-r--r-- | fs/ocfs2/aops.c | 4 | ||||
| -rw-r--r-- | fs/ocfs2/file.c | 12 |
3 files changed, 17 insertions, 24 deletions
diff --git a/fs/direct-io.c b/fs/direct-io.c index 354cbdbc14bd..0a073c7125a6 100644 --- a/fs/direct-io.c +++ b/fs/direct-io.c @@ -297,8 +297,7 @@ static ssize_t dio_complete(struct dio *dio, loff_t offset, ssize_t ret, bool is aio_complete(dio->iocb, ret, 0); } - if (dio->flags & DIO_LOCKING) - inode_dio_done(dio->inode); + inode_dio_done(dio->inode); return ret; } @@ -1185,14 +1184,16 @@ direct_io_worker(int rw, struct kiocb *iocb, struct inode *inode, * For writes this function is called under i_mutex and returns with * i_mutex held, for reads, i_mutex is not held on entry, but it is * taken and dropped again before returning. - * The i_dio_count counter keeps track of the number of outstanding - * direct I/O requests, and truncate waits for it to reach zero. - * New references to i_dio_count must only be grabbed with i_mutex - * held. - * * - if the flags value does NOT contain DIO_LOCKING we don't use any * internal locking but rather rely on the filesystem to synchronize * direct I/O reads/writes versus each other and truncate. + * + * To help with locking against truncate we incremented the i_dio_count + * counter before starting direct I/O, and decrement it once we are done. + * Truncate can wait for it to reach zero to provide exclusion. It is + * expected that filesystem provide exclusion between new direct I/O + * and truncates. For DIO_LOCKING filesystems this is done by i_mutex, + * but other filesystems need to take care of this on their own. */ ssize_t __blockdev_direct_IO(int rw, struct kiocb *iocb, struct inode *inode, @@ -1270,14 +1271,14 @@ __blockdev_direct_IO(int rw, struct kiocb *iocb, struct inode *inode, goto out; } } - - /* - * Will be decremented at I/O completion time. - */ - atomic_inc(&inode->i_dio_count); } /* + * Will be decremented at I/O completion time. + */ + atomic_inc(&inode->i_dio_count); + + /* * For file extending writes updating i_size before data * writeouts complete can expose uninitialized blocks. So * even for AIO, we need to wait for i/o to complete before diff --git a/fs/ocfs2/aops.c b/fs/ocfs2/aops.c index de1d3953599d..524d6167fb63 100644 --- a/fs/ocfs2/aops.c +++ b/fs/ocfs2/aops.c @@ -567,10 +567,8 @@ static void ocfs2_dio_end_io(struct kiocb *iocb, /* this io's submitter should not have unlocked this before we could */ BUG_ON(!ocfs2_iocb_is_rw_locked(iocb)); - if (ocfs2_iocb_is_sem_locked(iocb)) { - inode_dio_done(inode); + if (ocfs2_iocb_is_sem_locked(iocb)) ocfs2_iocb_clear_sem_locked(iocb); - } ocfs2_iocb_clear_rw_locked(iocb); diff --git a/fs/ocfs2/file.c b/fs/ocfs2/file.c index 736283ca4a4c..22d604601957 100644 --- a/fs/ocfs2/file.c +++ b/fs/ocfs2/file.c @@ -2240,7 +2240,6 @@ static ssize_t ocfs2_file_aio_write(struct kiocb *iocb, relock: /* to match setattr's i_mutex -> rw_lock ordering */ if (direct_io) { - atomic_inc(&inode->i_dio_count); have_alloc_sem = 1; /* communicate with ocfs2_dio_end_io */ ocfs2_iocb_set_sem_locked(iocb); @@ -2292,7 +2291,6 @@ relock: */ if (direct_io && !can_do_direct) { ocfs2_rw_unlock(inode, rw_level); - inode_dio_done(inode); have_alloc_sem = 0; rw_level = -1; @@ -2379,10 +2377,8 @@ out: ocfs2_rw_unlock(inode, rw_level); out_sems: - if (have_alloc_sem) { - inode_dio_done(inode); + if (have_alloc_sem) ocfs2_iocb_clear_sem_locked(iocb); - } mutex_unlock(&inode->i_mutex); @@ -2533,7 +2529,6 @@ static ssize_t ocfs2_file_aio_read(struct kiocb *iocb, */ if (filp->f_flags & O_DIRECT) { have_alloc_sem = 1; - atomic_inc(&inode->i_dio_count); ocfs2_iocb_set_sem_locked(iocb); ret = ocfs2_rw_lock(inode, 0); @@ -2575,10 +2570,9 @@ static ssize_t ocfs2_file_aio_read(struct kiocb *iocb, } bail: - if (have_alloc_sem) { - inode_dio_done(inode); + if (have_alloc_sem) ocfs2_iocb_clear_sem_locked(iocb); - } + if (rw_level != -1) ocfs2_rw_unlock(inode, rw_level); |