4.20-stable review patch. If anyone has any objections, please let me know. ------------------ From: Jan Kara <jack@xxxxxxx> commit c371077000f4138ee3c15fbed50101ff24bdc91d upstream. Push loop_ctl_mutex down to loop_change_fd(). We will need this to be able to call loop_reread_partitions() without loop_ctl_mutex. Signed-off-by: Jan Kara <jack@xxxxxxx> Signed-off-by: Jens Axboe <axboe@xxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/block/loop.c | 22 +++++++++++----------- 1 file changed, 11 insertions(+), 11 deletions(-) --- a/drivers/block/loop.c +++ b/drivers/block/loop.c @@ -691,19 +691,22 @@ static int loop_change_fd(struct loop_de struct file *file, *old_file; int error; + error = mutex_lock_killable_nested(&loop_ctl_mutex, 1); + if (error) + return error; error = -ENXIO; if (lo->lo_state != Lo_bound) - goto out; + goto out_unlock; /* the loop device has to be read-only */ error = -EINVAL; if (!(lo->lo_flags & LO_FLAGS_READ_ONLY)) - goto out; + goto out_unlock; error = -EBADF; file = fget(arg); if (!file) - goto out; + goto out_unlock; error = loop_validate_file(file, bdev); if (error) @@ -730,11 +733,13 @@ static int loop_change_fd(struct loop_de fput(old_file); if (lo->lo_flags & LO_FLAGS_PARTSCAN) loop_reread_partitions(lo, bdev); + mutex_unlock(&loop_ctl_mutex); return 0; - out_putf: +out_putf: fput(file); - out: +out_unlock: + mutex_unlock(&loop_ctl_mutex); return error; } @@ -1469,12 +1474,7 @@ static int lo_ioctl(struct block_device case LOOP_SET_FD: return loop_set_fd(lo, mode, bdev, arg); case LOOP_CHANGE_FD: - err = mutex_lock_killable_nested(&loop_ctl_mutex, 1); - if (err) - return err; - err = loop_change_fd(lo, bdev, arg); - mutex_unlock(&loop_ctl_mutex); - break; + return loop_change_fd(lo, bdev, arg); case LOOP_CLR_FD: return loop_clr_fd(lo); case LOOP_SET_STATUS:
