4.20-stable review patch. If anyone has any objections, please let me know.
------------------
From: Jan Kara jack@suse.cz
commit 757ecf40b7e029529768eb5f9562d5eeb3002106 upstream.
Push lo_ctl_mutex down to loop_set_fd(). We will need this to be able to call loop_reread_partitions() without lo_ctl_mutex.
Signed-off-by: Jan Kara jack@suse.cz Signed-off-by: Jens Axboe axboe@kernel.dk Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- drivers/block/loop.c | 26 ++++++++++++++------------ 1 file changed, 14 insertions(+), 12 deletions(-)
--- a/drivers/block/loop.c +++ b/drivers/block/loop.c @@ -918,13 +918,17 @@ static int loop_set_fd(struct loop_devic if (!file) goto out;
+ error = mutex_lock_killable_nested(&loop_ctl_mutex, 1); + if (error) + goto out_putf; + error = -EBUSY; if (lo->lo_state != Lo_unbound) - goto out_putf; + goto out_unlock;
error = loop_validate_file(file, bdev); if (error) - goto out_putf; + goto out_unlock;
mapping = file->f_mapping; inode = mapping->host; @@ -936,10 +940,10 @@ static int loop_set_fd(struct loop_devic error = -EFBIG; size = get_loop_size(lo, file); if ((loff_t)(sector_t)size != size) - goto out_putf; + goto out_unlock; error = loop_prepare_queue(lo); if (error) - goto out_putf; + goto out_unlock;
error = 0;
@@ -978,11 +982,14 @@ static int loop_set_fd(struct loop_devic * put /dev/loopXX inode. Later in __loop_clr_fd() we bdput(bdev). */ bdgrab(bdev); + mutex_unlock(&loop_ctl_mutex); return 0;
- out_putf: +out_unlock: + mutex_unlock(&loop_ctl_mutex); +out_putf: fput(file); - out: +out: /* This is safe: open() is still holding a reference. */ module_put(THIS_MODULE); return error; @@ -1460,12 +1467,7 @@ static int lo_ioctl(struct block_device
switch (cmd) { case LOOP_SET_FD: - err = mutex_lock_killable_nested(&loop_ctl_mutex, 1); - if (err) - return err; - err = loop_set_fd(lo, mode, bdev, arg); - mutex_unlock(&loop_ctl_mutex); - break; + return loop_set_fd(lo, mode, bdev, arg); case LOOP_CHANGE_FD: err = mutex_lock_killable_nested(&loop_ctl_mutex, 1); if (err)