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 list_head running_list; 27 atomic_t dropped; 28 }; 29 30 struct blkcg; 31 32 extern int blk_trace_ioctl(struct block_device *, unsigned, char __user *); 33 extern void blk_trace_shutdown(struct request_queue *); 34 extern __printf(3, 4) 35 void __trace_note_message(struct blk_trace *, struct blkcg *blkcg, const char *fmt, ...); 36 37 /** 38 * blk_add_trace_msg - Add a (simple) message to the blktrace stream 39 * @q: queue the io is for 40 * @fmt: format to print message in 41 * args... Variable argument list for format 42 * 43 * Description: 44 * Records a (simple) message onto the blktrace stream. 45 * 46 * NOTE: BLK_TN_MAX_MSG characters are output at most. 47 * NOTE: Can not use 'static inline' due to presence of var args... 48 * 49 **/ 50 #define blk_add_cgroup_trace_msg(q, cg, fmt, ...) \ 51 do { \ 52 struct blk_trace *bt; \ 53 \ 54 rcu_read_lock(); \ 55 bt = rcu_dereference((q)->blk_trace); \ 56 if (unlikely(bt)) \ 57 __trace_note_message(bt, cg, fmt, ##__VA_ARGS__);\ 58 rcu_read_unlock(); \ 59 } while (0) 60 #define blk_add_trace_msg(q, fmt, ...) \ 61 blk_add_cgroup_trace_msg(q, NULL, fmt, ##__VA_ARGS__) 62 #define BLK_TN_MAX_MSG 128 63 64 static inline bool blk_trace_note_message_enabled(struct request_queue *q) 65 { 66 struct blk_trace *bt; 67 bool ret; 68 69 rcu_read_lock(); 70 bt = rcu_dereference(q->blk_trace); 71 ret = bt && (bt->act_mask & BLK_TC_NOTIFY); 72 rcu_read_unlock(); 73 return ret; 74 } 75 76 extern void blk_add_driver_data(struct request *rq, void *data, size_t len); 77 extern int blk_trace_setup(struct request_queue *q, char *name, dev_t dev, 78 struct block_device *bdev, 79 char __user *arg); 80 extern int blk_trace_startstop(struct request_queue *q, int start); 81 extern int blk_trace_remove(struct request_queue *q); 82 extern void blk_trace_remove_sysfs(struct device *dev); 83 extern int blk_trace_init_sysfs(struct device *dev); 84 85 extern struct attribute_group blk_trace_attr_group; 86 87 #else /* !CONFIG_BLK_DEV_IO_TRACE */ 88 # define blk_trace_ioctl(bdev, cmd, arg) (-ENOTTY) 89 # define blk_trace_shutdown(q) do { } while (0) 90 # define blk_add_driver_data(rq, data, len) do {} while (0) 91 # define blk_trace_setup(q, name, dev, bdev, arg) (-ENOTTY) 92 # define blk_trace_startstop(q, start) (-ENOTTY) 93 # define blk_trace_remove(q) (-ENOTTY) 94 # define blk_add_trace_msg(q, fmt, ...) do { } while (0) 95 # define blk_add_cgroup_trace_msg(q, cg, fmt, ...) do { } while (0) 96 # define blk_trace_remove_sysfs(dev) do { } while (0) 97 # define blk_trace_note_message_enabled(q) (false) 98 static inline int blk_trace_init_sysfs(struct device *dev) 99 { 100 return 0; 101 } 102 103 #endif /* CONFIG_BLK_DEV_IO_TRACE */ 104 105 #ifdef CONFIG_COMPAT 106 107 struct compat_blk_user_trace_setup { 108 char name[BLKTRACE_BDEV_SIZE]; 109 u16 act_mask; 110 u32 buf_size; 111 u32 buf_nr; 112 compat_u64 start_lba; 113 compat_u64 end_lba; 114 u32 pid; 115 }; 116 #define BLKTRACESETUP32 _IOWR(0x12, 115, struct compat_blk_user_trace_setup) 117 118 #endif 119 120 void blk_fill_rwbs(char *rwbs, unsigned int op); 121 122 static inline sector_t blk_rq_trace_sector(struct request *rq) 123 { 124 /* 125 * Tracing should ignore starting sector for passthrough requests and 126 * requests where starting sector didn't get set. 127 */ 128 if (blk_rq_is_passthrough(rq) || blk_rq_pos(rq) == (sector_t)-1) 129 return 0; 130 return blk_rq_pos(rq); 131 } 132 133 static inline unsigned int blk_rq_trace_nr_sectors(struct request *rq) 134 { 135 return blk_rq_is_passthrough(rq) ? 0 : blk_rq_sectors(rq); 136 } 137 138 #endif 139