From 02afc27faec94c9e068517a22acf55400976c698 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Wed, 4 Sep 2013 15:04:40 +0200 Subject: direct-io: Handle O_(D)SYNC AIO Call generic_write_sync() from the deferred I/O completion handler if O_DSYNC is set for a write request. Also make sure various callers don't call generic_write_sync if the direct I/O code returns -EIOCBQUEUED. Based on an earlier patch from Jan Kara with updates from Jeff Moyer and Darrick J. Wong . Signed-off-by: Christoph Hellwig Signed-off-by: Jan Kara Signed-off-by: Al Viro --- fs/direct-io.c | 45 ++++++++++++++++++++++++++++++++++++--------- 1 file changed, 36 insertions(+), 9 deletions(-) (limited to 'fs/direct-io.c') diff --git a/fs/direct-io.c b/fs/direct-io.c index 8b31b9f449f4..1782023bd68a 100644 --- a/fs/direct-io.c +++ b/fs/direct-io.c @@ -266,8 +266,18 @@ static ssize_t dio_complete(struct dio *dio, loff_t offset, ssize_t ret, dio->end_io(dio->iocb, offset, transferred, dio->private); inode_dio_done(dio->inode); - if (is_async) + if (is_async) { + if (dio->rw & WRITE) { + int err; + + err = generic_write_sync(dio->iocb->ki_filp, offset, + transferred); + if (err < 0 && ret > 0) + ret = err; + } + aio_complete(dio->iocb, ret, 0); + } kmem_cache_free(dio_cache, dio); return ret; @@ -1182,11 +1192,6 @@ do_blockdev_direct_IO(int rw, struct kiocb *iocb, struct inode *inode, } } - /* - * 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 @@ -1195,11 +1200,33 @@ do_blockdev_direct_IO(int rw, struct kiocb *iocb, struct inode *inode, */ dio->is_async = !is_sync_kiocb(iocb) && !((rw & WRITE) && (end > i_size_read(inode))); - - retval = 0; - dio->inode = inode; dio->rw = rw; + + /* + * For AIO O_(D)SYNC writes we need to defer completions to a workqueue + * so that we can call ->fsync. + */ + if (dio->is_async && (rw & WRITE) && + ((iocb->ki_filp->f_flags & O_DSYNC) || + IS_SYNC(iocb->ki_filp->f_mapping->host))) { + retval = dio_set_defer_completion(dio); + if (retval) { + /* + * We grab i_mutex only for reads so we don't have + * to release it here + */ + kmem_cache_free(dio_cache, dio); + goto out; + } + } + + /* + * Will be decremented at I/O completion time. + */ + atomic_inc(&inode->i_dio_count); + + retval = 0; sdio.blkbits = blkbits; sdio.blkfactor = i_blkbits - blkbits; sdio.block_in_file = offset >> blkbits; -- cgit v1.2.3