From: Kent Overstreet <kent.overstreet@gmail.com>
Date: Thu, 11 Nov 2021 20:50:22 +0000 (-0500)
Subject: bcachefs: Fix infinite loop in bch2_btree_cache_scan()
X-Git-Tag: io_uring-6.7-2023-11-10~119^2~1297
X-Git-Url: https://git.kernel.dk/?a=commitdiff_plain;h=54b2db3d58eadb4496a671d43b1e7c0506dd0220;p=linux-block.git

bcachefs: Fix infinite loop in bch2_btree_cache_scan()

When attempting to free btree nodes, we might not be able to free all
the nodes that were requested. But the code was looping until it had
freed _all_ the nodes requested, when it should have only been
attempting to free nr nodes.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
---

diff --git a/fs/bcachefs/btree_cache.c b/fs/bcachefs/btree_cache.c
index 7f5620a4d7c5..4e855ae51731 100644
--- a/fs/bcachefs/btree_cache.c
+++ b/fs/bcachefs/btree_cache.c
@@ -309,7 +309,7 @@ static unsigned long bch2_btree_cache_scan(struct shrinker *shrink,
 
 		touched++;
 
-		if (freed >= nr)
+		if (touched >= nr)
 			break;
 
 		if (!btree_node_reclaim(c, b)) {
@@ -323,7 +323,7 @@ restart:
 	list_for_each_entry_safe(b, t, &bc->live, list) {
 		touched++;
 
-		if (freed >= nr) {
+		if (touched >= nr) {
 			/* Save position */
 			if (&t->list != &bc->live)
 				list_move_tail(&bc->live, &t->list);