From: Trond Myklebust <Trond.Myklebust@netapp.com>
Date: Thu, 5 Jun 2008 19:17:39 +0000 (-0400)
Subject: NFS: Fix a preemption count leak in nfs_update_request
X-Git-Tag: firefly_0821_release~19647^2~1^2~64
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=f3d47a3a6a1484a93c8cfe1e8c8d4399c95199c7;p=firefly-linux-kernel-4.4.55.git

NFS: Fix a preemption count leak in nfs_update_request

The commit 2785259631697ebb0749a3782cca206e2e542939 (nfs: use GFP_NOFS
preloads for radix-tree insertion) appears to have introduced a bug:
We only want to call radix_tree_preload() once after creating a request.
Calling it every time we loop after we created the request, will cause
preemption count leaks.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: Nick Piggin <npiggin@suse.de>
---

diff --git a/fs/nfs/write.c b/fs/nfs/write.c
index f333848fd3be..dc62bc504693 100644
--- a/fs/nfs/write.c
+++ b/fs/nfs/write.c
@@ -584,13 +584,6 @@ static struct nfs_page * nfs_update_request(struct nfs_open_context* ctx,
 		/* Loop over all inode entries and see if we find
 		 * A request for the page we wish to update
 		 */
-		if (new) {
-			if (radix_tree_preload(GFP_NOFS)) {
-				nfs_release_request(new);
-				return ERR_PTR(-ENOMEM);
-			}
-		}
-
 		spin_lock(&inode->i_lock);
 		req = nfs_page_find_request_locked(page);
 		if (req) {
@@ -630,6 +623,10 @@ static struct nfs_page * nfs_update_request(struct nfs_open_context* ctx,
 		new = nfs_create_request(ctx, inode, page, offset, bytes);
 		if (IS_ERR(new))
 			return new;
+		if (radix_tree_preload(GFP_NOFS)) {
+			nfs_release_request(new);
+			return ERR_PTR(-ENOMEM);
+		}
 	}
 
 	/* We have a request for our page.