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 15 struct 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 32 struct blkcg; 33 34 extern int blk_trace_ioctl(struct block_device *, unsigned, char __user *); 35 extern void blk_trace_shutdown(struct request_queue *); 36 extern __printf(3, 4) 37 void __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; \ 55 \ 56 rcu_read_lock(); \ 57 bt = rcu_dereference((q)->blk_trace); \ 58 if (unlikely(bt)) \ 59 __trace_note_message(bt, cg, fmt, ##__VA_ARGS__);\ 60 rcu_read_unlock(); \ 61 } while (0) 62 #define blk_add_trace_msg(q, fmt, ...) \ 63 blk_add_cgroup_trace_msg(q, NULL, fmt, ##__VA_ARGS__) 64 #define BLK_TN_MAX_MSG 128 65 66 static inline bool blk_trace_note_message_enabled(struct request_queue *q) 67 { 68 struct blk_trace *bt; 69 bool ret; 70 71 rcu_read_lock(); 72 bt = rcu_dereference(q->blk_trace); 73 ret = bt && (bt->act_mask & BLK_TC_NOTIFY); 74 rcu_read_unlock(); 75 return ret; 76 } 77 78 extern void blk_add_driver_data(struct request_queue *q, struct request *rq, 79 void *data, size_t len); 80 extern int blk_trace_setup(struct request_queue *q, char *name, dev_t dev, 81 struct block_device *bdev, 82 char __user *arg); 83 extern int blk_trace_startstop(struct request_queue *q, int start); 84 extern int blk_trace_remove(struct request_queue *q); 85 extern void blk_trace_remove_sysfs(struct device *dev); 86 extern int blk_trace_init_sysfs(struct device *dev); 87 88 extern struct attribute_group blk_trace_attr_group; 89 90 #else /* !CONFIG_BLK_DEV_IO_TRACE */ 91 # define blk_trace_ioctl(bdev, cmd, arg) (-ENOTTY) 92 # define blk_trace_shutdown(q) do { } while (0) 93 # define blk_add_driver_data(q, rq, data, len) do {} while (0) 94 # define blk_trace_setup(q, name, dev, bdev, arg) (-ENOTTY) 95 # define blk_trace_startstop(q, start) (-ENOTTY) 96 # define blk_trace_remove(q) (-ENOTTY) 97 # define blk_add_trace_msg(q, fmt, ...) do { } while (0) 98 # define blk_add_cgroup_trace_msg(q, cg, fmt, ...) do { } while (0) 99 # define blk_trace_remove_sysfs(dev) do { } while (0) 100 # define blk_trace_note_message_enabled(q) (false) 101 static inline int blk_trace_init_sysfs(struct device *dev) 102 { 103 return 0; 104 } 105 106 #endif /* CONFIG_BLK_DEV_IO_TRACE */ 107 108 #ifdef CONFIG_COMPAT 109 110 struct compat_blk_user_trace_setup { 111 char name[BLKTRACE_BDEV_SIZE]; 112 u16 act_mask; 113 u32 buf_size; 114 u32 buf_nr; 115 compat_u64 start_lba; 116 compat_u64 end_lba; 117 u32 pid; 118 }; 119 #define BLKTRACESETUP32 _IOWR(0x12, 115, struct compat_blk_user_trace_setup) 120 121 #endif 122 123 extern void blk_fill_rwbs(char *rwbs, unsigned int op, int bytes); 124 125 static inline sector_t blk_rq_trace_sector(struct request *rq) 126 { 127 /* 128 * Tracing should ignore starting sector for passthrough requests and 129 * requests where starting sector didn't get set. 130 */ 131 if (blk_rq_is_passthrough(rq) || blk_rq_pos(rq) == (sector_t)-1) 132 return 0; 133 return blk_rq_pos(rq); 134 } 135 136 static inline unsigned int blk_rq_trace_nr_sectors(struct request *rq) 137 { 138 return blk_rq_is_passthrough(rq) ? 0 : blk_rq_sectors(rq); 139 } 140 141 #endif 142