diff options
Diffstat (limited to 'block/cfq-iosched.c')
| -rw-r--r-- | block/cfq-iosched.c | 61 |
1 files changed, 56 insertions, 5 deletions
diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c index 7a7230136e43..97da5719c87a 100644 --- a/block/cfq-iosched.c +++ b/block/cfq-iosched.c @@ -1740,7 +1740,7 @@ static int cfq_print_leaf_weight(struct seq_file *sf, void *v) static ssize_t __cfqg_set_weight_device(struct kernfs_open_file *of, char *buf, size_t nbytes, loff_t off, - bool is_leaf_weight) + bool on_dfl, bool is_leaf_weight) { struct blkcg *blkcg = css_to_blkcg(of_css(of)); struct blkg_conf_ctx ctx; @@ -1753,9 +1753,17 @@ static ssize_t __cfqg_set_weight_device(struct kernfs_open_file *of, if (ret) return ret; - ret = -EINVAL; - if (sscanf(ctx.body, "%llu", &v) != 1) + if (sscanf(ctx.body, "%llu", &v) == 1) { + /* require "default" on dfl */ + ret = -ERANGE; + if (!v && on_dfl) + goto out_finish; + } else if (!strcmp(strim(ctx.body), "default")) { + v = 0; + } else { + ret = -EINVAL; goto out_finish; + } cfqg = blkg_to_cfqg(ctx.blkg); cfqgd = blkcg_to_cfqgd(blkcg); @@ -1779,13 +1787,13 @@ out_finish: static ssize_t cfqg_set_weight_device(struct kernfs_open_file *of, char *buf, size_t nbytes, loff_t off) { - return __cfqg_set_weight_device(of, buf, nbytes, off, false); + return __cfqg_set_weight_device(of, buf, nbytes, off, false, false); } static ssize_t cfqg_set_leaf_weight_device(struct kernfs_open_file *of, char *buf, size_t nbytes, loff_t off) { - return __cfqg_set_weight_device(of, buf, nbytes, off, true); + return __cfqg_set_weight_device(of, buf, nbytes, off, false, true); } static int __cfq_set_weight(struct cgroup_subsys_state *css, u64 val, @@ -2103,6 +2111,48 @@ static struct cftype cfq_blkcg_legacy_files[] = { #endif /* CONFIG_DEBUG_BLK_CGROUP */ { } /* terminate */ }; + +static int cfq_print_weight_on_dfl(struct seq_file *sf, void *v) +{ + struct blkcg *blkcg = css_to_blkcg(seq_css(sf)); + struct cfq_group_data *cgd = blkcg_to_cfqgd(blkcg); + + seq_printf(sf, "default %u\n", cgd->weight); + blkcg_print_blkgs(sf, blkcg, cfqg_prfill_weight_device, + &blkcg_policy_cfq, 0, false); + return 0; +} + +static ssize_t cfq_set_weight_on_dfl(struct kernfs_open_file *of, + char *buf, size_t nbytes, loff_t off) +{ + char *endp; + int ret; + u64 v; + + buf = strim(buf); + + /* "WEIGHT" or "default WEIGHT" sets the default weight */ + v = simple_strtoull(buf, &endp, 0); + if (*endp == '\0' || sscanf(buf, "default %llu", &v) == 1) { + ret = __cfq_set_weight(of_css(of), v, false); + return ret ?: nbytes; + } + + /* "MAJ:MIN WEIGHT" */ + return __cfqg_set_weight_device(of, buf, nbytes, off, true, false); +} + +static struct cftype cfq_blkcg_files[] = { + { + .name = "weight", + .flags = CFTYPE_NOT_ON_ROOT, + .seq_show = cfq_print_weight_on_dfl, + .write = cfq_set_weight_on_dfl, + }, + { } /* terminate */ +}; + #else /* GROUP_IOSCHED */ static struct cfq_group *cfq_lookup_cfqg(struct cfq_data *cfqd, struct blkcg *blkcg) @@ -4659,6 +4709,7 @@ static struct elevator_type iosched_cfq = { #ifdef CONFIG_CFQ_GROUP_IOSCHED static struct blkcg_policy blkcg_policy_cfq = { + .dfl_cftypes = cfq_blkcg_files, .legacy_cftypes = cfq_blkcg_legacy_files, .cpd_alloc_fn = cfq_cpd_alloc, |