block: remove plugging at buffered write time

Buffered write(2) is not directly tied to IO, so it's not suitable to
handle plug in generic_file_aio_write().

Note that plugging for O_SYNC writes is also removed. The user may pass
arbitrary @size arguments, which may be much larger than the preferable
I/O size, or may cross extent/device boundaries. Let the lower layers
handle the plugging. The plugging code here actually turns them into
no-ops.

CC: Li Shaohua <shli@fusionio.com>
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Fengguang Wu 2012-08-09 15:23:07 +02:00 коммит произвёл Jens Axboe
Родитель 276f0f5d15
Коммит 8430f9772f
1 изменённых файлов: 0 добавлений и 3 удалений

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@ -2527,14 +2527,12 @@ ssize_t generic_file_aio_write(struct kiocb *iocb, const struct iovec *iov,
{
struct file *file = iocb->ki_filp;
struct inode *inode = file->f_mapping->host;
struct blk_plug plug;
ssize_t ret;
BUG_ON(iocb->ki_pos != pos);
sb_start_write(inode->i_sb);
mutex_lock(&inode->i_mutex);
blk_start_plug(&plug);
ret = __generic_file_aio_write(iocb, iov, nr_segs, &iocb->ki_pos);
mutex_unlock(&inode->i_mutex);
@ -2545,7 +2543,6 @@ ssize_t generic_file_aio_write(struct kiocb *iocb, const struct iovec *iov,
if (err < 0 && ret > 0)
ret = err;
}
blk_finish_plug(&plug);
sb_end_write(inode->i_sb);
return ret;
}