[PATCH 04/11] xfs: cleanup _xfs_buf_get_pages

[Christoph Hellwig <hch@lst.de>]

Remove the check for an existing b_pages array as this function is always
called right after allocating a buffer, so this can't happen.  Also
use kmem_zalloc to allocate the page array instead of doing a manual
memset gіven that the inline array is already pre-zeroed as part of the
freshly allocated buffer anyway.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 fs/xfs/xfs_buf.c | 23 +++++++++++------------
 1 file changed, 11 insertions(+), 12 deletions(-)

diff --git a/fs/xfs/xfs_buf.c b/fs/xfs/xfs_buf.c
index 392b85d059bff5..9c64c374411081 100644
--- a/fs/xfs/xfs_buf.c
+++ b/fs/xfs/xfs_buf.c
@@ -281,19 +281,18 @@ _xfs_buf_get_pages(
 	struct xfs_buf		*bp,
 	int			page_count)
 {
-	/* Make sure that we have a page list */
-	if (bp->b_pages == NULL) {
-		bp->b_page_count = page_count;
-		if (page_count <= XB_PAGES) {
-			bp->b_pages = bp->b_page_array;
-		} else {
-			bp->b_pages = kmem_alloc(sizeof(struct page *) *
-						 page_count, KM_NOFS);
-			if (bp->b_pages == NULL)
-				return -ENOMEM;
-		}
-		memset(bp->b_pages, 0, sizeof(struct page *) * page_count);
+	ASSERT(bp->b_pages == NULL);
+
+	bp->b_page_count = page_count;
+	if (page_count > XB_PAGES) {
+		bp->b_pages = kmem_zalloc(sizeof(struct page *) * page_count,
+					  KM_NOFS);
+		if (!bp->b_pages)
+			return -ENOMEM;
+	} else {
+		bp->b_pages = bp->b_page_array;
 	}
+
 	return 0;
 }
 
-- 
2.30.2