[patch 04/43] fuse: destroy bdi on umount

Greg KH
2009-01-31T02:59:57Z

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[-- Type: text/plain, Size: 1757 bytes --]

2.6.28-stable review patch. If anyone has any objections, please let us know.

------------------

From: Miklos Szeredi <mszeredi@suse.cz>

commit 26c3679101dbccc054dcf370143941844ba70531 upstream.

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>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

---
fs/fuse/dev.c | 3 ++-
fs/fuse/inode.c | 2 +-
2 files changed, 3 insertions(+), 2 deletions(-)

--- a/fs/fuse/dev.c
+++ b/fs/fuse/dev.c
@@ -281,7 +281,8 @@ static void request_end(struct fuse_conn
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);
}
--- a/fs/fuse/inode.c
+++ b/fs/fuse/inode.c
@@ -292,6 +292,7 @@ static void fuse_put_super(struct super_
list_del(&fc->entry);
fuse_ctl_remove_conn(fc);
mutex_unlock(&fuse_mutex);
+ bdi_destroy(&fc->bdi);
fuse_conn_put(fc);
}

@@ -531,7 +532,6 @@ 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);
kfree(fc);
}
}