diff options
Diffstat (limited to 'include/linux/blk-cgroup.h')
| -rw-r--r-- | include/linux/blk-cgroup.h | 63 |
1 files changed, 63 insertions, 0 deletions
diff --git a/include/linux/blk-cgroup.h b/include/linux/blk-cgroup.h index b9f3c246c3c9..37048438872c 100644 --- a/include/linux/blk-cgroup.h +++ b/include/linux/blk-cgroup.h @@ -30,6 +30,8 @@ /* Max limits for throttle policy */ #define THROTL_IOPS_MAX UINT_MAX +#define FC_APPID_LEN 129 + #ifdef CONFIG_BLK_CGROUP @@ -55,6 +57,9 @@ struct blkcg { struct blkcg_policy_data *cpd[BLKCG_MAX_POLS]; struct list_head all_blkcgs_node; +#ifdef CONFIG_BLK_CGROUP_FC_APPID + char fc_app_id[FC_APPID_LEN]; +#endif #ifdef CONFIG_CGROUP_WRITEBACK struct list_head cgwb_list; #endif @@ -660,4 +665,62 @@ static inline void blk_cgroup_bio_start(struct bio *bio) { } #endif /* CONFIG_BLOCK */ #endif /* CONFIG_BLK_CGROUP */ + +#ifdef CONFIG_BLK_CGROUP_FC_APPID +/* + * Sets the fc_app_id field associted to blkcg + * @app_id: application identifier + * @cgrp_id: cgroup id + * @app_id_len: size of application identifier + */ +static inline int blkcg_set_fc_appid(char *app_id, u64 cgrp_id, size_t app_id_len) +{ + struct cgroup *cgrp; + struct cgroup_subsys_state *css; + struct blkcg *blkcg; + int ret = 0; + + if (app_id_len > FC_APPID_LEN) + return -EINVAL; + + cgrp = cgroup_get_from_id(cgrp_id); + if (!cgrp) + return -ENOENT; + css = cgroup_get_e_css(cgrp, &io_cgrp_subsys); + if (!css) { + ret = -ENOENT; + goto out_cgrp_put; + } + blkcg = css_to_blkcg(css); + /* + * There is a slight race condition on setting the appid. + * Worst case an I/O may not find the right id. + * This is no different from the I/O we let pass while obtaining + * the vmid from the fabric. + * Adding the overhead of a lock is not necessary. + */ + strlcpy(blkcg->fc_app_id, app_id, app_id_len); + css_put(css); +out_cgrp_put: + cgroup_put(cgrp); + return ret; +} + +/** + * blkcg_get_fc_appid - get the fc app identifier associated with a bio + * @bio: target bio + * + * On success return the fc_app_id, on failure return NULL + */ +static inline char *blkcg_get_fc_appid(struct bio *bio) +{ + if (bio && bio->bi_blkg && + (bio->bi_blkg->blkcg->fc_app_id[0] != '\0')) + return bio->bi_blkg->blkcg->fc_app_id; + return NULL; +} +#else +static inline int blkcg_set_fc_appid(char *buf, u64 id, size_t len) { return -EINVAL; } +static inline char *blkcg_get_fc_appid(struct bio *bio) { return NULL; } +#endif /*CONFIG_BLK_CGROUP_FC_APPID*/ #endif /* _BLK_CGROUP_H */ |