Line data    Source code

       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           9 : static inline int blk_trace_init_sysfs(struct device *dev)
      99             : {
     100           9 :         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           0 : 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           0 :         if (blk_rq_is_passthrough(rq) || blk_rq_pos(rq) == (sector_t)-1)
     129           0 :                 return 0;
     130           0 :         return blk_rq_pos(rq);
     131             : }
     132             : 
     133           0 : static inline unsigned int blk_rq_trace_nr_sectors(struct request *rq)
     134             : {
     135           0 :         return blk_rq_is_passthrough(rq) ? 0 : blk_rq_sectors(rq);
     136             : }
     137             : 
     138             : #endif