f2fs: add nowait aio support
This patch adds nowait aio support[1].
Return EAGAIN if any of the following checks fail for direct I/O:
- i_rwsem is not lockable
- Blocks are not allocated at the write location
And xfstests generic/471 is passed.
[1]: 6be96d "Introduce RWF_NOWAIT and FMODE_AIO_NOWAIT"
Signed-off-by: Hyunchul Lee <cheol.lee@lge.com>
Reviewed-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
index 3ad75f0..87d2742 100644
--- a/fs/f2fs/file.c
+++ b/fs/f2fs/file.c
@@ -481,6 +481,9 @@
if (err)
return err;
+
+ filp->f_mode |= FMODE_NOWAIT;
+
return dquot_file_open(inode, filp);
}
@@ -2692,7 +2695,15 @@
if (unlikely(f2fs_cp_error(F2FS_I_SB(inode))))
return -EIO;
- inode_lock(inode);
+ if ((iocb->ki_flags & IOCB_NOWAIT) && !(iocb->ki_flags & IOCB_DIRECT))
+ return -EINVAL;
+
+ if (!inode_trylock(inode)) {
+ if (iocb->ki_flags & IOCB_NOWAIT)
+ return -EAGAIN;
+ inode_lock(inode);
+ }
+
ret = generic_write_checks(iocb, from);
if (ret > 0) {
int err;
@@ -2700,11 +2711,23 @@
if (iov_iter_fault_in_readable(from, iov_iter_count(from)))
set_inode_flag(inode, FI_NO_PREALLOC);
- err = f2fs_preallocate_blocks(iocb, from);
- if (err) {
- clear_inode_flag(inode, FI_NO_PREALLOC);
- inode_unlock(inode);
- return err;
+ if ((iocb->ki_flags & IOCB_NOWAIT) &&
+ (iocb->ki_flags & IOCB_DIRECT)) {
+ if (!f2fs_overwrite_io(inode, iocb->ki_pos,
+ iov_iter_count(from)) ||
+ f2fs_has_inline_data(inode) ||
+ f2fs_force_buffered_io(inode, WRITE)) {
+ inode_unlock(inode);
+ return -EAGAIN;
+ }
+
+ } else {
+ err = f2fs_preallocate_blocks(iocb, from);
+ if (err) {
+ clear_inode_flag(inode, FI_NO_PREALLOC);
+ inode_unlock(inode);
+ return err;
+ }
}
blk_start_plug(&plug);
ret = __generic_file_write_iter(iocb, from);