1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef BLKTRACE_H
3#define BLKTRACE_H
4
5#include <linux/blkdev.h>
6#include <linux/relay.h>
7#include <linux/compat.h>
8#include <uapi/linux/blktrace_api.h>
9#include <linux/list.h>
10
11#if defined(CONFIG_BLK_DEV_IO_TRACE)
12
13#include <linux/sysfs.h>
14
15struct blk_trace {
16 int trace_state;
17 struct rchan *rchan;
18 unsigned long __percpu *sequence;
19 unsigned char __percpu *msg_data;
20 u16 act_mask;
21 u64 start_lba;
22 u64 end_lba;
23 u32 pid;
24 u32 dev;
25 struct dentry *dir;
26 struct dentry *dropped_file;
27 struct dentry *msg_file;
28 struct list_head running_list;
29 atomic_t dropped;
30};
31
32struct blkcg;
33
34extern int blk_trace_ioctl(struct block_device *, unsigned, char __user *);
35extern void blk_trace_shutdown(struct request_queue *);
36extern __printf(3, 4)
37void __trace_note_message(struct blk_trace *, struct blkcg *blkcg, const char *fmt, ...);
38
39/**
40 * blk_add_trace_msg - Add a (simple) message to the blktrace stream
41 * @q: queue the io is for
42 * @fmt: format to print message in
43 * args... Variable argument list for format
44 *
45 * Description:
46 * Records a (simple) message onto the blktrace stream.
47 *
48 * NOTE: BLK_TN_MAX_MSG characters are output at most.
49 * NOTE: Can not use 'static inline' due to presence of var args...
50 *
51 **/
52#define blk_add_cgroup_trace_msg(q, cg, fmt, ...) \
53 do { \
54 struct blk_trace *bt = (q)->blk_trace; \
55 if (unlikely(bt)) \
56 __trace_note_message(bt, cg, fmt, ##__VA_ARGS__);\
57 } while (0)
58#define blk_add_trace_msg(q, fmt, ...) \
59 blk_add_cgroup_trace_msg(q, NULL, fmt, ##__VA_ARGS__)
60#define BLK_TN_MAX_MSG 128
61
62static inline bool blk_trace_note_message_enabled(struct request_queue *q)
63{
64 struct blk_trace *bt = q->blk_trace;
65 if (likely(!bt))
66 return false;
67 return bt->act_mask & BLK_TC_NOTIFY;
68}
69
70extern void blk_add_driver_data(struct request_queue *q, struct request *rq,
71 void *data, size_t len);
72extern int blk_trace_setup(struct request_queue *q, char *name, dev_t dev,
73 struct block_device *bdev,
74 char __user *arg);
75extern int blk_trace_startstop(struct request_queue *q, int start);
76extern int blk_trace_remove(struct request_queue *q);
77extern void blk_trace_remove_sysfs(struct device *dev);
78extern int blk_trace_init_sysfs(struct device *dev);
79
80extern struct attribute_group blk_trace_attr_group;
81
82#else /* !CONFIG_BLK_DEV_IO_TRACE */
83# define blk_trace_ioctl(bdev, cmd, arg) (-ENOTTY)
84# define blk_trace_shutdown(q) do { } while (0)
85# define blk_add_driver_data(q, rq, data, len) do {} while (0)
86# define blk_trace_setup(q, name, dev, bdev, arg) (-ENOTTY)
87# define blk_trace_startstop(q, start) (-ENOTTY)
88# define blk_trace_remove(q) (-ENOTTY)
89# define blk_add_trace_msg(q, fmt, ...) do { } while (0)
90# define blk_add_cgroup_trace_msg(q, cg, fmt, ...) do { } while (0)
91# define blk_trace_remove_sysfs(dev) do { } while (0)
92# define blk_trace_note_message_enabled(q) (false)
93static inline int blk_trace_init_sysfs(struct device *dev)
94{
95 return 0;
96}
97
98#endif /* CONFIG_BLK_DEV_IO_TRACE */
99
100#ifdef CONFIG_COMPAT
101
102struct compat_blk_user_trace_setup {
103 char name[BLKTRACE_BDEV_SIZE];
104 u16 act_mask;
105 u32 buf_size;
106 u32 buf_nr;
107 compat_u64 start_lba;
108 compat_u64 end_lba;
109 u32 pid;
110};
111#define BLKTRACESETUP32 _IOWR(0x12, 115, struct compat_blk_user_trace_setup)
112
113#endif
114
115extern void blk_fill_rwbs(char *rwbs, unsigned int op, int bytes);
116
117static inline sector_t blk_rq_trace_sector(struct request *rq)
118{
119 /*
120 * Tracing should ignore starting sector for passthrough requests and
121 * requests where starting sector didn't get set.
122 */
123 if (blk_rq_is_passthrough(rq) || blk_rq_pos(rq) == (sector_t)-1)
124 return 0;
125 return blk_rq_pos(rq);
126}
127
128static inline unsigned int blk_rq_trace_nr_sectors(struct request *rq)
129{
130 return blk_rq_is_passthrough(rq) ? 0 : blk_rq_sectors(rq);
131}
132
133#endif
134