fuse: fuse_flush must check mapping->flags for errors

[ Upstream commit 9ebce595f63a407c5cec98f98f9da8459b73740a ]

fuse_flush() calls write_inode_now() that triggers writeback, but actual
writeback will happen later, on fuse_sync_writes(). If an error happens,
fuse_writepage_end() will set error bit in mapping->flags. So, we have to
check mapping->flags after fuse_sync_writes().

Signed-off-by: Maxim Patlasov <mpatlasov@virtuozzo.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Fixes: 4d99ff8f12eb ("fuse: Turn writeback cache on")
Cc: <stable@vger.kernel.org> # v3.15+
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>

diff --git a/fs/fuse/file.c b/fs/fuse/file.c
index afdff12c094934ad695d9a4a7904b89e49da7883..8e2c5ccc09b163bfe858eccc1d6fc198c801a7be 100644 (file)
--- a/fs/fuse/file.c
+++ b/fs/fuse/file.c
@@ -454,6 +454,15 @@ static int fuse_flush(struct file *file, fl_owner_t id)
        fuse_sync_writes(inode);
        mutex_unlock(&inode->i_mutex);
 
+       if (test_bit(AS_ENOSPC, &file->f_mapping->flags) &&
+           test_and_clear_bit(AS_ENOSPC, &file->f_mapping->flags))
+               err = -ENOSPC;
+       if (test_bit(AS_EIO, &file->f_mapping->flags) &&
+           test_and_clear_bit(AS_EIO, &file->f_mapping->flags))
+               err = -EIO;
+       if (err)
+               return err;
+
        req = fuse_get_req_nofail_nopages(fc, file);
        memset(&inarg, 0, sizeof(inarg));
        inarg.fh = ff->fh;