Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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linux
1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef BLKTRACE_H
3#define BLKTRACE_H
4
5#include <linux/blk-mq.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 list_head running_list;
27 atomic_t dropped;
28};
29
30extern int blk_trace_ioctl(struct block_device *, unsigned, char __user *);
31extern void blk_trace_shutdown(struct request_queue *);
32__printf(3, 4) void __blk_trace_note_message(struct blk_trace *bt,
33 struct cgroup_subsys_state *css, const char *fmt, ...);
34
35/**
36 * blk_add_trace_msg - Add a (simple) message to the blktrace stream
37 * @q: queue the io is for
38 * @fmt: format to print message in
39 * args... Variable argument list for format
40 *
41 * Description:
42 * Records a (simple) message onto the blktrace stream.
43 *
44 * NOTE: BLK_TN_MAX_MSG characters are output at most.
45 * NOTE: Can not use 'static inline' due to presence of var args...
46 *
47 **/
48#define blk_add_cgroup_trace_msg(q, css, fmt, ...) \
49 do { \
50 struct blk_trace *bt; \
51 \
52 rcu_read_lock(); \
53 bt = rcu_dereference((q)->blk_trace); \
54 if (unlikely(bt)) \
55 __blk_trace_note_message(bt, css, fmt, ##__VA_ARGS__);\
56 rcu_read_unlock(); \
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;
65 bool ret;
66
67 rcu_read_lock();
68 bt = rcu_dereference(q->blk_trace);
69 ret = bt && (bt->act_mask & BLK_TC_NOTIFY);
70 rcu_read_unlock();
71 return ret;
72}
73
74extern void blk_add_driver_data(struct request *rq, void *data, size_t len);
75extern int blk_trace_setup(struct request_queue *q, char *name, dev_t dev,
76 struct block_device *bdev,
77 char __user *arg);
78extern int blk_trace_startstop(struct request_queue *q, int start);
79extern int blk_trace_remove(struct request_queue *q);
80extern void blk_trace_remove_sysfs(struct device *dev);
81extern int blk_trace_init_sysfs(struct device *dev);
82
83extern struct attribute_group blk_trace_attr_group;
84
85#else /* !CONFIG_BLK_DEV_IO_TRACE */
86# define blk_trace_ioctl(bdev, cmd, arg) (-ENOTTY)
87# define blk_trace_shutdown(q) do { } while (0)
88# define blk_add_driver_data(rq, data, len) do {} while (0)
89# define blk_trace_setup(q, name, dev, bdev, arg) (-ENOTTY)
90# define blk_trace_startstop(q, start) (-ENOTTY)
91# define blk_trace_remove(q) (-ENOTTY)
92# define blk_add_trace_msg(q, fmt, ...) do { } while (0)
93# define blk_add_cgroup_trace_msg(q, cg, fmt, ...) do { } while (0)
94# define blk_trace_remove_sysfs(dev) do { } while (0)
95# define blk_trace_note_message_enabled(q) (false)
96static inline int blk_trace_init_sysfs(struct device *dev)
97{
98 return 0;
99}
100
101#endif /* CONFIG_BLK_DEV_IO_TRACE */
102
103#ifdef CONFIG_COMPAT
104
105struct compat_blk_user_trace_setup {
106 char name[BLKTRACE_BDEV_SIZE];
107 u16 act_mask;
108 u32 buf_size;
109 u32 buf_nr;
110 compat_u64 start_lba;
111 compat_u64 end_lba;
112 u32 pid;
113};
114#define BLKTRACESETUP32 _IOWR(0x12, 115, struct compat_blk_user_trace_setup)
115
116#endif
117
118void blk_fill_rwbs(char *rwbs, unsigned int op);
119
120static inline sector_t blk_rq_trace_sector(struct request *rq)
121{
122 /*
123 * Tracing should ignore starting sector for passthrough requests and
124 * requests where starting sector didn't get set.
125 */
126 if (blk_rq_is_passthrough(rq) || blk_rq_pos(rq) == (sector_t)-1)
127 return 0;
128 return blk_rq_pos(rq);
129}
130
131static inline unsigned int blk_rq_trace_nr_sectors(struct request *rq)
132{
133 return blk_rq_is_passthrough(rq) ? 0 : blk_rq_sectors(rq);
134}
135
136#endif