Merge tag 'for-linus-5.4-1' of git://github.com/cminyard/linux-ipmi
[linux-2.6-block.git] / block / bfq-cgroup.c
index 0f6cd688924fbd23177438f4a2afba03331777bc..86a607cf19a1023271c4bd7a4090b451e2bb3fde 100644 (file)
@@ -501,11 +501,12 @@ static void bfq_cpd_free(struct blkcg_policy_data *cpd)
        kfree(cpd_to_bfqgd(cpd));
 }
 
-static struct blkg_policy_data *bfq_pd_alloc(gfp_t gfp, int node)
+static struct blkg_policy_data *bfq_pd_alloc(gfp_t gfp, struct request_queue *q,
+                                            struct blkcg *blkcg)
 {
        struct bfq_group *bfqg;
 
-       bfqg = kzalloc_node(sizeof(*bfqg), gfp, node);
+       bfqg = kzalloc_node(sizeof(*bfqg), gfp, q->node);
        if (!bfqg)
                return NULL;
 
@@ -904,7 +905,7 @@ void bfq_end_wr_async(struct bfq_data *bfqd)
        bfq_end_wr_async_queues(bfqd, bfqd->root_group);
 }
 
-static int bfq_io_show_weight(struct seq_file *sf, void *v)
+static int bfq_io_show_weight_legacy(struct seq_file *sf, void *v)
 {
        struct blkcg *blkcg = css_to_blkcg(seq_css(sf));
        struct bfq_group_data *bfqgd = blkcg_to_bfqgd(blkcg);
@@ -918,6 +919,60 @@ static int bfq_io_show_weight(struct seq_file *sf, void *v)
        return 0;
 }
 
+static u64 bfqg_prfill_weight_device(struct seq_file *sf,
+                                    struct blkg_policy_data *pd, int off)
+{
+       struct bfq_group *bfqg = pd_to_bfqg(pd);
+
+       if (!bfqg->entity.dev_weight)
+               return 0;
+       return __blkg_prfill_u64(sf, pd, bfqg->entity.dev_weight);
+}
+
+static int bfq_io_show_weight(struct seq_file *sf, void *v)
+{
+       struct blkcg *blkcg = css_to_blkcg(seq_css(sf));
+       struct bfq_group_data *bfqgd = blkcg_to_bfqgd(blkcg);
+
+       seq_printf(sf, "default %u\n", bfqgd->weight);
+       blkcg_print_blkgs(sf, blkcg, bfqg_prfill_weight_device,
+                         &blkcg_policy_bfq, 0, false);
+       return 0;
+}
+
+static void bfq_group_set_weight(struct bfq_group *bfqg, u64 weight, u64 dev_weight)
+{
+       weight = dev_weight ?: weight;
+
+       bfqg->entity.dev_weight = dev_weight;
+       /*
+        * Setting the prio_changed flag of the entity
+        * to 1 with new_weight == weight would re-set
+        * the value of the weight to its ioprio mapping.
+        * Set the flag only if necessary.
+        */
+       if ((unsigned short)weight != bfqg->entity.new_weight) {
+               bfqg->entity.new_weight = (unsigned short)weight;
+               /*
+                * Make sure that the above new value has been
+                * stored in bfqg->entity.new_weight before
+                * setting the prio_changed flag. In fact,
+                * this flag may be read asynchronously (in
+                * critical sections protected by a different
+                * lock than that held here), and finding this
+                * flag set may cause the execution of the code
+                * for updating parameters whose value may
+                * depend also on bfqg->entity.new_weight (in
+                * __bfq_entity_update_weight_prio).
+                * This barrier makes sure that the new value
+                * of bfqg->entity.new_weight is correctly
+                * seen in that code.
+                */
+               smp_wmb();
+               bfqg->entity.prio_changed = 1;
+       }
+}
+
 static int bfq_io_set_weight_legacy(struct cgroup_subsys_state *css,
                                    struct cftype *cftype,
                                    u64 val)
@@ -936,55 +991,72 @@ static int bfq_io_set_weight_legacy(struct cgroup_subsys_state *css,
        hlist_for_each_entry(blkg, &blkcg->blkg_list, blkcg_node) {
                struct bfq_group *bfqg = blkg_to_bfqg(blkg);
 
-               if (!bfqg)
-                       continue;
-               /*
-                * Setting the prio_changed flag of the entity
-                * to 1 with new_weight == weight would re-set
-                * the value of the weight to its ioprio mapping.
-                * Set the flag only if necessary.
-                */
-               if ((unsigned short)val != bfqg->entity.new_weight) {
-                       bfqg->entity.new_weight = (unsigned short)val;
-                       /*
-                        * Make sure that the above new value has been
-                        * stored in bfqg->entity.new_weight before
-                        * setting the prio_changed flag. In fact,
-                        * this flag may be read asynchronously (in
-                        * critical sections protected by a different
-                        * lock than that held here), and finding this
-                        * flag set may cause the execution of the code
-                        * for updating parameters whose value may
-                        * depend also on bfqg->entity.new_weight (in
-                        * __bfq_entity_update_weight_prio).
-                        * This barrier makes sure that the new value
-                        * of bfqg->entity.new_weight is correctly
-                        * seen in that code.
-                        */
-                       smp_wmb();
-                       bfqg->entity.prio_changed = 1;
-               }
+               if (bfqg)
+                       bfq_group_set_weight(bfqg, val, 0);
        }
        spin_unlock_irq(&blkcg->lock);
 
        return ret;
 }
 
-static ssize_t bfq_io_set_weight(struct kernfs_open_file *of,
-                                char *buf, size_t nbytes,
-                                loff_t off)
+static ssize_t bfq_io_set_device_weight(struct kernfs_open_file *of,
+                                       char *buf, size_t nbytes,
+                                       loff_t off)
 {
-       u64 weight;
-       /* First unsigned long found in the file is used */
-       int ret = kstrtoull(strim(buf), 0, &weight);
+       int ret;
+       struct blkg_conf_ctx ctx;
+       struct blkcg *blkcg = css_to_blkcg(of_css(of));
+       struct bfq_group *bfqg;
+       u64 v;
 
+       ret = blkg_conf_prep(blkcg, &blkcg_policy_bfq, buf, &ctx);
        if (ret)
                return ret;
 
-       ret = bfq_io_set_weight_legacy(of_css(of), NULL, weight);
+       if (sscanf(ctx.body, "%llu", &v) == 1) {
+               /* require "default" on dfl */
+               ret = -ERANGE;
+               if (!v)
+                       goto out;
+       } else if (!strcmp(strim(ctx.body), "default")) {
+               v = 0;
+       } else {
+               ret = -EINVAL;
+               goto out;
+       }
+
+       bfqg = blkg_to_bfqg(ctx.blkg);
+
+       ret = -ERANGE;
+       if (!v || (v >= BFQ_MIN_WEIGHT && v <= BFQ_MAX_WEIGHT)) {
+               bfq_group_set_weight(bfqg, bfqg->entity.weight, v);
+               ret = 0;
+       }
+out:
+       blkg_conf_finish(&ctx);
        return ret ?: nbytes;
 }
 
+static ssize_t bfq_io_set_weight(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 = bfq_io_set_weight_legacy(of_css(of), NULL, v);
+               return ret ?: nbytes;
+       }
+
+       return bfq_io_set_device_weight(of, buf, nbytes, off);
+}
+
 #ifdef CONFIG_BFQ_CGROUP_DEBUG
 static int bfqg_print_stat(struct seq_file *sf, void *v)
 {
@@ -1141,9 +1213,15 @@ struct cftype bfq_blkcg_legacy_files[] = {
        {
                .name = "bfq.weight",
                .flags = CFTYPE_NOT_ON_ROOT,
-               .seq_show = bfq_io_show_weight,
+               .seq_show = bfq_io_show_weight_legacy,
                .write_u64 = bfq_io_set_weight_legacy,
        },
+       {
+               .name = "bfq.weight_device",
+               .flags = CFTYPE_NOT_ON_ROOT,
+               .seq_show = bfq_io_show_weight,
+               .write = bfq_io_set_weight,
+       },
 
        /* statistics, covers only the tasks in the bfqg */
        {