fuse: destroy bdi on umount

If a fuse filesystem is unmounted but the device file descriptor
remains open and a new mount reuses the old device number, then the
mount fails with EEXIST and the following warning is printed in the
kernel log:

  WARNING: at fs/sysfs/dir.c:462 sysfs_add_one+0x35/0x3d()
  sysfs: duplicate filename '0:15' can not be created

The cause is that the bdi belonging to the fuse filesystem was
destoryed only after the device file was released.  Fix this by
calling bdi_destroy() from fuse_put_super() instead.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
CC: stable@kernel.org
This commit is contained in:
Miklos Szeredi 2009-01-26 15:00:59 +01:00 committed by Miklos Szeredi
parent c2b8f00690
commit 26c3679101
2 changed files with 3 additions and 2 deletions

View file

@ -281,7 +281,8 @@ __releases(&fc->lock)
fc->blocked = 0;
wake_up_all(&fc->blocked_waitq);
}
if (fc->num_background == FUSE_CONGESTION_THRESHOLD) {
if (fc->num_background == FUSE_CONGESTION_THRESHOLD &&
fc->connected) {
clear_bdi_congested(&fc->bdi, READ);
clear_bdi_congested(&fc->bdi, WRITE);
}

View file

@ -292,6 +292,7 @@ static void fuse_put_super(struct super_block *sb)
list_del(&fc->entry);
fuse_ctl_remove_conn(fc);
mutex_unlock(&fuse_mutex);
bdi_destroy(&fc->bdi);
fuse_conn_put(fc);
}
@ -532,7 +533,6 @@ void fuse_conn_put(struct fuse_conn *fc)
if (fc->destroy_req)
fuse_request_free(fc->destroy_req);
mutex_destroy(&fc->inst_mutex);
bdi_destroy(&fc->bdi);
fc->release(fc);
}
}