Re: [PATCH 8/8] nowait aio: btrfs
From: David Sterba <hidden>
Date: 2017-04-18 11:39:08
Also in:
linux-block, linux-btrfs, linux-ext4, linux-fsdevel, linux-xfs
On Fri, Apr 14, 2017 at 07:02:57AM -0500, Goldwyn Rodrigues wrote:
From: Goldwyn Rodrigues <rgoldwyn-IBi9RG/b67k@public.gmane.org> Return EAGAIN if any of the following checks fail + i_rwsem is not lockable + NODATACOW or PREALLOC is not set + Cannot nocow at the desired location + Writing beyond end of file which is not allocated Signed-off-by: Goldwyn Rodrigues <rgoldwyn-IBi9RG/b67k@public.gmane.org>
Acked-by: David Sterba <dsterba-IBi9RG/b67k@public.gmane.org>
+ if ((iocb->ki_flags & IOCB_NOWAIT) &&
+ (iocb->ki_flags & IOCB_DIRECT)) {
+ /* Don't sleep on inode rwsem */
+ if (!inode_trylock(inode))
+ return -EAGAIN;
+ /*
+ * We will allocate space in case nodatacow is not set,
+ * so bail
+ */
+ if (!(BTRFS_I(inode)->flags & (BTRFS_INODE_NODATACOW |
+ BTRFS_INODE_PREALLOC)) ||
+ check_can_nocow(BTRFS_I(inode), pos, &count) <= 0) {
+ inode_unlock(inode);
+ return -EAGAIN;
+ }
+ } else
} else {
+ inode_lock(inode);
}