diff options
authorKay Sievers <kay.sievers@vrfy.org>2008-12-02 10:31:50 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2008-12-02 15:50:40 -0800
commitf1d0b063d993527754f062c589b73f125024d216 (patch)
parent1b79cd04fab80be61dcd2732e2423aafde9a4c1c (diff)
bdi: register sysfs bdi device only once per queue
Devices which share the same queue, like floppies and mtd devices, get registered multiple times in the bdi interface, but bdi accounts only the last registered device of the devices sharing one queue. On remove, all earlier registered devices leak, stay around in sysfs, and cause "duplicate filename" errors if the devices are re-created. This prevents the creation of multiple bdi interfaces per queue, and the bdi device will carry the dev_t name of the block device which is the first one registered, of the pool of devices using the same queue. [akpm@linux-foundation.org: add a WARN_ON so we know which drivers are misbehaving] Tested-by: Peter Korsgaard <jacmet@sunsite.dk> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Cc: David Woodhouse <dwmw2@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
1 files changed, 3 insertions, 0 deletions
diff --git a/mm/backing-dev.c b/mm/backing-dev.c
index f2e574dbc30..2a56124dbc2 100644
--- a/mm/backing-dev.c
+++ b/mm/backing-dev.c
@@ -176,6 +176,9 @@ int bdi_register(struct backing_dev_info *bdi, struct device *parent,
int ret = 0;
struct device *dev;
+ if (WARN_ON(bdi->dev))
+ goto exit;
va_start(args, fmt);
dev = device_create_vargs(bdi_class, parent, MKDEV(0, 0), bdi, fmt, args);