blktrace_api.h 3.9 KB

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