1 /*
2  * loop.h
3  *
4  * Written by Theodore Ts'o, 3/29/93.
5  *
6  * Copyright 1993 by Theodore Ts'o.  Redistribution of this file is
7  * permitted under the GNU General Public License.
8  */
9 #ifndef _LINUX_LOOP_H
10 #define _LINUX_LOOP_H
11 
12 #include <linux/bio.h>
13 #include <linux/blkdev.h>
14 #include <linux/blk-mq.h>
15 #include <linux/spinlock.h>
16 #include <linux/mutex.h>
17 #include <uapi/linux/loop.h>
18 
19 /* Possible states of device */
20 enum {
21 	Lo_unbound,
22 	Lo_bound,
23 	Lo_rundown,
24 	Lo_deleting,
25 };
26 
27 struct loop_func_table;
28 
29 struct loop_device {
30 	int		lo_number;
31 	atomic_t	lo_refcnt;
32 	loff_t		lo_offset;
33 	loff_t		lo_sizelimit;
34 	int		lo_flags;
35 	char		lo_file_name[LO_NAME_SIZE];
36 
37 	struct file *	lo_backing_file;
38 	struct block_device *lo_device;
39 
40 	gfp_t		old_gfp_mask;
41 
42 	spinlock_t		lo_lock;
43 	int			lo_state;
44 	spinlock_t              lo_work_lock;
45 	struct workqueue_struct *workqueue;
46 	struct work_struct      rootcg_work;
47 	struct list_head        rootcg_cmd_list;
48 	struct list_head        idle_worker_list;
49 	struct rb_root          worker_tree;
50 	struct timer_list       timer;
51 	bool			use_dio;
52 	bool			sysfs_inited;
53 
54 	struct request_queue	*lo_queue;
55 	struct blk_mq_tag_set	tag_set;
56 	struct gendisk		*lo_disk;
57 	struct mutex		lo_mutex;
58 	bool			idr_visible;
59 };
60 
61 struct loop_cmd {
62 	struct list_head list_entry;
63 	bool use_aio; /* use AIO interface to handle I/O */
64 	atomic_t ref; /* only for aio */
65 	long ret;
66 	struct kiocb iocb;
67 	struct bio_vec *bvec;
68 	struct cgroup_subsys_state *blkcg_css;
69 	struct cgroup_subsys_state *memcg_css;
70 };
71 
72 #endif
73