cgroup: pass around cgroup_subsys_state instead of cgroup in file methods

cgroup is currently in the process of transitioning to using struct
cgroup_subsys_state * as the primary handle instead of struct cgroup.
Please see the previous commit which converts the subsystem methods
for rationale.

This patch converts all cftype file operations to take @css instead of
@cgroup.  cftypes for the cgroup core files don't have their subsytem
pointer set.  These will automatically use the dummy_css added by the
previous patch and can be converted the same way.

Most subsystem conversions are straight forwards but there are some
interesting ones.

* freezer: update_if_frozen() is also converted to take @css instead
  of @cgroup for consistency.  This will make the code look simpler
  too once iterators are converted to use css.

* memory/vmpressure: mem_cgroup_from_css() needs to be exported to
  vmpressure while mem_cgroup_from_cont() can be made static.
  Updated accordingly.

* cpu: cgroup_tg() doesn't have any user left.  Removed.

* cpuacct: cgroup_ca() doesn't have any user left.  Removed.

* hugetlb: hugetlb_cgroup_form_cgroup() doesn't have any user left.
  Removed.

* net_cls: cgrp_cls_state() doesn't have any user left.  Removed.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizefan@huawei.com>
Acked-by: Michal Hocko <mhocko@suse.cz>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
Acked-by: Aristeu Rozanski <aris@redhat.com>
Acked-by: Daniel Wagner <daniel.wagner@bmw-carit.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Balbir Singh <bsingharora@gmail.com>
Cc: Matt Helsley <matthltc@us.ibm.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Steven Rostedt <rostedt@goodmis.org>

3 files changed, 64 insertions, 64 deletions

diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c
index 34063739745b..f46f3c69179c 100644
--- a/block/blk-cgroup.c
+++ b/block/blk-cgroup.c
@@ -437,10 +437,10 @@ struct request_list *__blk_queue_next_rl(struct request_list *rl,
         return &blkg->rl;
 }
 
-static int blkcg_reset_stats(struct cgroup *cgroup, struct cftype *cftype,
-                             u64 val)
+static int blkcg_reset_stats(struct cgroup_subsys_state *css,
+                             struct cftype *cftype, u64 val)
 {
-        struct blkcg *blkcg = cgroup_to_blkcg(cgroup);
+        struct blkcg *blkcg = css_to_blkcg(css);
         struct blkcg_gq *blkg;
         int i;
 
diff --git a/block/blk-throttle.c b/block/blk-throttle.c
index 08a32dfd3844..88bcfb651b0b 100644
--- a/block/blk-throttle.c
+++ b/block/blk-throttle.c
@@ -1293,10 +1293,10 @@ static u64 tg_prfill_cpu_rwstat(struct seq_file *sf,
         return __blkg_prfill_rwstat(sf, pd, &rwstat);
 }
 
-static int tg_print_cpu_rwstat(struct cgroup *cgrp, struct cftype *cft,
-                               struct seq_file *sf)
+static int tg_print_cpu_rwstat(struct cgroup_subsys_state *css,
+                               struct cftype *cft, struct seq_file *sf)
 {
-        struct blkcg *blkcg = cgroup_to_blkcg(cgrp);
+        struct blkcg *blkcg = css_to_blkcg(css);
 
         blkcg_print_blkgs(sf, blkcg, tg_prfill_cpu_rwstat, &blkcg_policy_throtl,
                           cft->private, true);
@@ -1325,26 +1325,26 @@ static u64 tg_prfill_conf_uint(struct seq_file *sf, struct blkg_policy_data *pd,
         return __blkg_prfill_u64(sf, pd, v);
 }
 
-static int tg_print_conf_u64(struct cgroup *cgrp, struct cftype *cft,
-                             struct seq_file *sf)
+static int tg_print_conf_u64(struct cgroup_subsys_state *css,
+                             struct cftype *cft, struct seq_file *sf)
 {
-        blkcg_print_blkgs(sf, cgroup_to_blkcg(cgrp), tg_prfill_conf_u64,
+        blkcg_print_blkgs(sf, css_to_blkcg(css), tg_prfill_conf_u64,
                           &blkcg_policy_throtl, cft->private, false);
         return 0;
 }
 
-static int tg_print_conf_uint(struct cgroup *cgrp, struct cftype *cft,
-                              struct seq_file *sf)
+static int tg_print_conf_uint(struct cgroup_subsys_state *css,
+                              struct cftype *cft, struct seq_file *sf)
 {
-        blkcg_print_blkgs(sf, cgroup_to_blkcg(cgrp), tg_prfill_conf_uint,
+        blkcg_print_blkgs(sf, css_to_blkcg(css), tg_prfill_conf_uint,
                           &blkcg_policy_throtl, cft->private, false);
         return 0;
 }
 
-static int tg_set_conf(struct cgroup *cgrp, struct cftype *cft, const char *buf,
-                       bool is_u64)
+static int tg_set_conf(struct cgroup_subsys_state *css, struct cftype *cft,
+                       const char *buf, bool is_u64)
 {
-        struct blkcg *blkcg = cgroup_to_blkcg(cgrp);
+        struct blkcg *blkcg = css_to_blkcg(css);
         struct blkg_conf_ctx ctx;
         struct throtl_grp *tg;
         struct throtl_service_queue *sq;
@@ -1403,16 +1403,16 @@ static int tg_set_conf(struct cgroup *cgrp, struct cftype *cft, const char *buf,
         return 0;
 }
 
-static int tg_set_conf_u64(struct cgroup *cgrp, struct cftype *cft,
+static int tg_set_conf_u64(struct cgroup_subsys_state *css, struct cftype *cft,
                            const char *buf)
 {
-        return tg_set_conf(cgrp, cft, buf, true);
+        return tg_set_conf(css, cft, buf, true);
 }
 
-static int tg_set_conf_uint(struct cgroup *cgrp, struct cftype *cft,
+static int tg_set_conf_uint(struct cgroup_subsys_state *css, struct cftype *cft,
                             const char *buf)
 {
-        return tg_set_conf(cgrp, cft, buf, false);
+        return tg_set_conf(css, cft, buf, false);
 }
 
 static struct cftype throtl_files[] = {
diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c
index d5bbdcfd0dab..dabb9d02cf9a 100644
--- a/block/cfq-iosched.c
+++ b/block/cfq-iosched.c
@@ -1607,12 +1607,11 @@ static u64 cfqg_prfill_weight_device(struct seq_file *sf,
         return __blkg_prfill_u64(sf, pd, cfqg->dev_weight);
 }
 
-static int cfqg_print_weight_device(struct cgroup *cgrp, struct cftype *cft,
-                                    struct seq_file *sf)
+static int cfqg_print_weight_device(struct cgroup_subsys_state *css,
+                                    struct cftype *cft, struct seq_file *sf)
 {
-        blkcg_print_blkgs(sf, cgroup_to_blkcg(cgrp),
-                          cfqg_prfill_weight_device, &blkcg_policy_cfq, 0,
-                          false);
+        blkcg_print_blkgs(sf, css_to_blkcg(css), cfqg_prfill_weight_device,
+                          &blkcg_policy_cfq, 0, false);
         return 0;
 }
 
@@ -1626,35 +1625,34 @@ static u64 cfqg_prfill_leaf_weight_device(struct seq_file *sf,
         return __blkg_prfill_u64(sf, pd, cfqg->dev_leaf_weight);
 }
 
-static int cfqg_print_leaf_weight_device(struct cgroup *cgrp,
+static int cfqg_print_leaf_weight_device(struct cgroup_subsys_state *css,
                                          struct cftype *cft,
                                          struct seq_file *sf)
 {
-        blkcg_print_blkgs(sf, cgroup_to_blkcg(cgrp),
-                          cfqg_prfill_leaf_weight_device, &blkcg_policy_cfq, 0,
-                          false);
+        blkcg_print_blkgs(sf, css_to_blkcg(css), cfqg_prfill_leaf_weight_device,
+                          &blkcg_policy_cfq, 0, false);
         return 0;
 }
 
-static int cfq_print_weight(struct cgroup *cgrp, struct cftype *cft,
+static int cfq_print_weight(struct cgroup_subsys_state *css, struct cftype *cft,
                             struct seq_file *sf)
 {
-        seq_printf(sf, "%u\n", cgroup_to_blkcg(cgrp)->cfq_weight);
+        seq_printf(sf, "%u\n", css_to_blkcg(css)->cfq_weight);
         return 0;
 }
 
-static int cfq_print_leaf_weight(struct cgroup *cgrp, struct cftype *cft,
-                                 struct seq_file *sf)
+static int cfq_print_leaf_weight(struct cgroup_subsys_state *css,
+                                 struct cftype *cft, struct seq_file *sf)
 {
-        seq_printf(sf, "%u\n",
-                   cgroup_to_blkcg(cgrp)->cfq_leaf_weight);
+        seq_printf(sf, "%u\n", css_to_blkcg(css)->cfq_leaf_weight);
         return 0;
 }
 
-static int __cfqg_set_weight_device(struct cgroup *cgrp, struct cftype *cft,
-                                    const char *buf, bool is_leaf_weight)
+static int __cfqg_set_weight_device(struct cgroup_subsys_state *css,
+                                    struct cftype *cft, const char *buf,
+                                    bool is_leaf_weight)
 {
-        struct blkcg *blkcg = cgroup_to_blkcg(cgrp);
+        struct blkcg *blkcg = css_to_blkcg(css);
         struct blkg_conf_ctx ctx;
         struct cfq_group *cfqg;
         int ret;
@@ -1680,22 +1678,22 @@ static int __cfqg_set_weight_device(struct cgroup *cgrp, struct cftype *cft,
         return ret;
 }
 
-static int cfqg_set_weight_device(struct cgroup *cgrp, struct cftype *cft,
-                                  const char *buf)
+static int cfqg_set_weight_device(struct cgroup_subsys_state *css,
+                                  struct cftype *cft, const char *buf)
 {
-        return __cfqg_set_weight_device(cgrp, cft, buf, false);
+        return __cfqg_set_weight_device(css, cft, buf, false);
 }
 
-static int cfqg_set_leaf_weight_device(struct cgroup *cgrp, struct cftype *cft,
-                                       const char *buf)
+static int cfqg_set_leaf_weight_device(struct cgroup_subsys_state *css,
+                                       struct cftype *cft, const char *buf)
 {
-        return __cfqg_set_weight_device(cgrp, cft, buf, true);
+        return __cfqg_set_weight_device(css, cft, buf, true);
 }
 
-static int __cfq_set_weight(struct cgroup *cgrp, struct cftype *cft, u64 val,
-                            bool is_leaf_weight)
+static int __cfq_set_weight(struct cgroup_subsys_state *css, struct cftype *cft,
+                            u64 val, bool is_leaf_weight)
 {
-        struct blkcg *blkcg = cgroup_to_blkcg(cgrp);
+        struct blkcg *blkcg = css_to_blkcg(css);
         struct blkcg_gq *blkg;
 
         if (val < CFQ_WEIGHT_MIN || val > CFQ_WEIGHT_MAX)
@@ -1727,30 +1725,32 @@ static int __cfq_set_weight(struct cgroup *cgrp, struct cftype *cft, u64 val,
         return 0;
 }
 
-static int cfq_set_weight(struct cgroup *cgrp, struct cftype *cft, u64 val)
+static int cfq_set_weight(struct cgroup_subsys_state *css, struct cftype *cft,
+                          u64 val)
 {
-        return __cfq_set_weight(cgrp, cft, val, false);
+        return __cfq_set_weight(css, cft, val, false);
 }
 
-static int cfq_set_leaf_weight(struct cgroup *cgrp, struct cftype *cft, u64 val)
+static int cfq_set_leaf_weight(struct cgroup_subsys_state *css,
+                               struct cftype *cft, u64 val)
 {
-        return __cfq_set_weight(cgrp, cft, val, true);
+        return __cfq_set_weight(css, cft, val, true);
 }
 
-static int cfqg_print_stat(struct cgroup *cgrp, struct cftype *cft,
+static int cfqg_print_stat(struct cgroup_subsys_state *css, struct cftype *cft,
                            struct seq_file *sf)
 {
-        struct blkcg *blkcg = cgroup_to_blkcg(cgrp);
+        struct blkcg *blkcg = css_to_blkcg(css);
 
         blkcg_print_blkgs(sf, blkcg, blkg_prfill_stat, &blkcg_policy_cfq,
                           cft->private, false);
         return 0;
 }
 
-static int cfqg_print_rwstat(struct cgroup *cgrp, struct cftype *cft,
-                             struct seq_file *sf)
+static int cfqg_print_rwstat(struct cgroup_subsys_state *css,
+                             struct cftype *cft, struct seq_file *sf)
 {
-        struct blkcg *blkcg = cgroup_to_blkcg(cgrp);
+        struct blkcg *blkcg = css_to_blkcg(css);
 
         blkcg_print_blkgs(sf, blkcg, blkg_prfill_rwstat, &blkcg_policy_cfq,
                           cft->private, true);
@@ -1773,20 +1773,20 @@ static u64 cfqg_prfill_rwstat_recursive(struct seq_file *sf,
         return __blkg_prfill_rwstat(sf, pd, &sum);
 }
 
-static int cfqg_print_stat_recursive(struct cgroup *cgrp, struct cftype *cft,
-                                     struct seq_file *sf)
+static int cfqg_print_stat_recursive(struct cgroup_subsys_state *css,
+                                     struct cftype *cft, struct seq_file *sf)
 {
-        struct blkcg *blkcg = cgroup_to_blkcg(cgrp);
+        struct blkcg *blkcg = css_to_blkcg(css);
 
         blkcg_print_blkgs(sf, blkcg, cfqg_prfill_stat_recursive,
                           &blkcg_policy_cfq, cft->private, false);
         return 0;
 }
 
-static int cfqg_print_rwstat_recursive(struct cgroup *cgrp, struct cftype *cft,
-                                       struct seq_file *sf)
+static int cfqg_print_rwstat_recursive(struct cgroup_subsys_state *css,
+                                       struct cftype *cft, struct seq_file *sf)
 {
-        struct blkcg *blkcg = cgroup_to_blkcg(cgrp);
+        struct blkcg *blkcg = css_to_blkcg(css);
 
         blkcg_print_blkgs(sf, blkcg, cfqg_prfill_rwstat_recursive,
                           &blkcg_policy_cfq, cft->private, true);
@@ -1810,10 +1810,10 @@ static u64 cfqg_prfill_avg_queue_size(struct seq_file *sf,
 }
 
 /* print avg_queue_size */
-static int cfqg_print_avg_queue_size(struct cgroup *cgrp, struct cftype *cft,
-                                     struct seq_file *sf)
+static int cfqg_print_avg_queue_size(struct cgroup_subsys_state *css,
+                                     struct cftype *cft, struct seq_file *sf)
 {
-        struct blkcg *blkcg = cgroup_to_blkcg(cgrp);
+        struct blkcg *blkcg = css_to_blkcg(css);
 
         blkcg_print_blkgs(sf, blkcg, cfqg_prfill_avg_queue_size,
                           &blkcg_policy_cfq, 0, false);