include/linux/blk-cgroup.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 #ifndef _BLK_CGROUP_H
   3 #define _BLK_CGROUP_H
   4 /*
   5  * Common Block IO controller cgroup interface
   6  *
   7  * Based on ideas and code from CFQ, CFS and BFQ:
   8  * Copyright (C) 2003 Jens Axboe <axboe@kernel.dk>
   9  *
  10  * Copyright (C) 2008 Fabio Checconi <fabio@gandalf.sssup.it>
  11  *                    Paolo Valente <paolo.valente@unimore.it>
  12  *
  13  * Copyright (C) 2009 Vivek Goyal <vgoyal@redhat.com>
  14  *                    Nauman Rafique <nauman@google.com>
  15  */
  16
  17 #include <linux/types.h>
  18
  19 struct bio;
  20 struct cgroup_subsys_state;
  21 struct gendisk;
  22
  23 #define FC_APPID_LEN              129
  24
  25 #ifdef CONFIG_BLK_CGROUP
  26 extern struct cgroup_subsys_state * const blkcg_root_css;
  27
  28 void blkcg_schedule_throttle(struct gendisk *disk, bool use_memdelay);
  29 void blkcg_maybe_throttle_current(void);
  30 bool blk_cgroup_congested(void);
  31 void blkcg_pin_online(struct cgroup_subsys_state *blkcg_css);
  32 void blkcg_unpin_online(struct cgroup_subsys_state *blkcg_css);
  33 struct list_head *blkcg_get_cgwb_list(struct cgroup_subsys_state *css);
  34 struct cgroup_subsys_state *bio_blkcg_css(struct bio *bio);
  35
  36 #else   /* CONFIG_BLK_CGROUP */
  37
  38 #define blkcg_root_css  ((struct cgroup_subsys_state *)ERR_PTR(-EINVAL))
  39
  40 static inline void blkcg_maybe_throttle_current(void) { }
  41 static inline bool blk_cgroup_congested(void) { return false; }
  42 static inline struct cgroup_subsys_state *bio_blkcg_css(struct bio *bio)
  43 {
  44         return NULL;
  45 }
  46 #endif  /* CONFIG_BLK_CGROUP */
  47
  48 int blkcg_set_fc_appid(char *app_id, u64 cgrp_id, size_t app_id_len);
  49 char *blkcg_get_fc_appid(struct bio *bio);
  50
  51 #endif  /* _BLK_CGROUP_H */