---

yaml --- r: 210895 b: refs/heads/master c: 371d217 h: refs/heads/master i: 210893: 39bc604 210891: 123f0c0 210887: 8c3f10e 210879: b04e361 v: v3
git-mirror · Sep 22, 2010 · 984907f · 984907f
1 parent 886c529
commit 984907f
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Showing 3 changed files with 6 additions and 3 deletions.
diff --git a/[refs] b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 976e48f8a5b02fc33f3e5cad87fb3fcea041a49c
+refs/heads/master: 371d217ee1ff8b418b8f73fb2a34990f951ec2d4
diff --git a/trunk/drivers/char/mem.c b/trunk/drivers/char/mem.c
@@ -788,10 +788,11 @@ static const struct file_operations zero_fops = {
 /*
  * capabilities for /dev/zero
  * - permits private mappings, "copies" are taken of the source of zeros
+ * - no writeback happens
  */
 static struct backing_dev_info zero_bdi = {
 	.name		= "char/mem",
-	.capabilities	= BDI_CAP_MAP_COPY,
+	.capabilities	= BDI_CAP_MAP_COPY | BDI_CAP_NO_ACCT_AND_WRITEBACK,
 };
 
 static const struct file_operations full_fops = {

diff --git a/trunk/fs/char_dev.c b/trunk/fs/char_dev.c
@@ -40,7 +40,9 @@ struct backing_dev_info directly_mappable_cdev_bdi = {
 #endif
 		/* permit direct mmap, for read, write or exec */
 		BDI_CAP_MAP_DIRECT |
-		BDI_CAP_READ_MAP | BDI_CAP_WRITE_MAP | BDI_CAP_EXEC_MAP),
+		BDI_CAP_READ_MAP | BDI_CAP_WRITE_MAP | BDI_CAP_EXEC_MAP |
+		/* no writeback happens */
+		BDI_CAP_NO_ACCT_AND_WRITEBACK),
 };
 
 static struct kobj_map *cdev_map;