splice: simplify a conditional in copy_splice_read

Check for -EFAULT instead of wrapping the check in an ret < 0 block.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Christian Brauner <brauner@kernel.org>
Reviewed-by: David Howells <dhowells@redhat.com>
Link: https://lore.kernel.org/r/20230614140341.521331-3-hch@lst.deSigned-off-by: Jens Axboe <axboe@kernel.dk>

fs/splice.c

@@ -368,15 +368,15 @@ ssize_t copy_splice_read(struct file *in, loff_t *ppos,
 	if (ret > 0) {
 		keep = DIV_ROUND_UP(ret, PAGE_SIZE);
 		*ppos = kiocb.ki_pos;
-	} else if (ret < 0) {
-		/*
-		 * callers of ->splice_read() expect -EAGAIN on
-		 * "can't put anything in there", rather than -EFAULT.
-		 */
-		if (ret == -EFAULT)
-			ret = -EAGAIN;
 	}
 
+	/*
+	 * Callers of ->splice_read() expect -EAGAIN on "can't put anything in
+	 * there", rather than -EFAULT.
+	 */
+	if (ret == -EFAULT)
+		ret = -EAGAIN;
+
 	/* Free any pages that didn't get touched at all. */
 	if (keep < npages)
 		release_pages(pages + keep, npages - keep);