1 files changed, 619 insertions, 131 deletions

diff --git a/mm/hugetlb_cgroup.c b/mm/hugetlb_cgroup.c
index eec1150125b9..58e895f3899a 100644
--- a/mm/hugetlb_cgroup.c
+++ b/mm/hugetlb_cgroup.c
@@ -3,6 +3,10 @@
  * Copyright IBM Corporation, 2012
  * Author Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
  *
+ * Cgroup v2
+ * Copyright (C) 2019 Red Hat, Inc.
+ * Author: Giuseppe Scrivano <gscrivan@redhat.com>
+ *
  * This program is free software; you can redistribute it and/or modify it
  * under the terms of version 2.1 of the GNU Lesser General Public License
  * as published by the Free Software Foundation.
@@ -19,19 +23,42 @@
 #include <linux/hugetlb.h>
 #include <linux/hugetlb_cgroup.h>
 
-struct hugetlb_cgroup {
-	struct cgroup_subsys_state css;
-	/*
-	 * the counter to account for hugepages from hugetlb.
-	 */
-	struct page_counter hugepage[HUGE_MAX_HSTATE];
-};
-
 #define MEMFILE_PRIVATE(x, val)	(((x) << 16) | (val))
 #define MEMFILE_IDX(val)	(((val) >> 16) & 0xffff)
 #define MEMFILE_ATTR(val)	((val) & 0xffff)
 
+/* Use t->m[0] to encode the offset */
+#define MEMFILE_OFFSET(t, m0)	(((offsetof(t, m0) << 16) | sizeof_field(t, m0)))
+#define MEMFILE_OFFSET0(val)	(((val) >> 16) & 0xffff)
+#define MEMFILE_FIELD_SIZE(val)	((val) & 0xffff)
+
+#define DFL_TMPL_SIZE		ARRAY_SIZE(hugetlb_dfl_tmpl)
+#define LEGACY_TMPL_SIZE	ARRAY_SIZE(hugetlb_legacy_tmpl)
+
 static struct hugetlb_cgroup *root_h_cgroup __read_mostly;
+static struct cftype *dfl_files;
+static struct cftype *legacy_files;
+
+static inline struct page_counter *
+__hugetlb_cgroup_counter_from_cgroup(struct hugetlb_cgroup *h_cg, int idx,
+				     bool rsvd)
+{
+	if (rsvd)
+		return &h_cg->rsvd_hugepage[idx];
+	return &h_cg->hugepage[idx];
+}
+
+static inline struct page_counter *
+hugetlb_cgroup_counter_from_cgroup(struct hugetlb_cgroup *h_cg, int idx)
+{
+	return __hugetlb_cgroup_counter_from_cgroup(h_cg, idx, false);
+}
+
+static inline struct page_counter *
+hugetlb_cgroup_counter_from_cgroup_rsvd(struct hugetlb_cgroup *h_cg, int idx)
+{
+	return __hugetlb_cgroup_counter_from_cgroup(h_cg, idx, true);
+}
 
 static inline
 struct hugetlb_cgroup *hugetlb_cgroup_from_css(struct cgroup_subsys_state *s)
@@ -58,10 +85,11 @@ parent_hugetlb_cgroup(struct hugetlb_cgroup *h_cg)
 
 static inline bool hugetlb_cgroup_have_usage(struct hugetlb_cgroup *h_cg)
 {
-	int idx;
+	struct hstate *h;
 
-	for (idx = 0; idx < hugetlb_max_hstate; idx++) {
-		if (page_counter_read(&h_cg->hugepage[idx]))
+	for_each_hstate(h) {
+		if (page_counter_read(
+		    hugetlb_cgroup_counter_from_cgroup(h_cg, hstate_index(h))))
 			return true;
 	}
 	return false;
@@ -73,48 +101,89 @@ static void hugetlb_cgroup_init(struct hugetlb_cgroup *h_cgroup,
 	int idx;
 
 	for (idx = 0; idx < HUGE_MAX_HSTATE; idx++) {
-		struct page_counter *counter = &h_cgroup->hugepage[idx];
-		struct page_counter *parent = NULL;
+		struct page_counter *fault, *fault_parent = NULL;
+		struct page_counter *rsvd, *rsvd_parent = NULL;
 		unsigned long limit;
-		int ret;
 
-		if (parent_h_cgroup)
-			parent = &parent_h_cgroup->hugepage[idx];
-		page_counter_init(counter, parent);
+		if (parent_h_cgroup) {
+			fault_parent = hugetlb_cgroup_counter_from_cgroup(
+				parent_h_cgroup, idx);
+			rsvd_parent = hugetlb_cgroup_counter_from_cgroup_rsvd(
+				parent_h_cgroup, idx);
+		}
+		fault = hugetlb_cgroup_counter_from_cgroup(h_cgroup, idx);
+		rsvd = hugetlb_cgroup_counter_from_cgroup_rsvd(h_cgroup, idx);
+
+		page_counter_init(fault, fault_parent, false);
+		page_counter_init(rsvd, rsvd_parent, false);
+
+		if (!cgroup_subsys_on_dfl(hugetlb_cgrp_subsys)) {
+			fault->track_failcnt = true;
+			rsvd->track_failcnt = true;
+		}
 
 		limit = round_down(PAGE_COUNTER_MAX,
-				   1 << huge_page_order(&hstates[idx]));
-		ret = page_counter_limit(counter, limit);
-		VM_BUG_ON(ret);
+				   pages_per_huge_page(&hstates[idx]));
+
+		VM_BUG_ON(page_counter_set_max(fault, limit));
+		VM_BUG_ON(page_counter_set_max(rsvd, limit));
 	}
 }
 
+static void hugetlb_cgroup_free(struct hugetlb_cgroup *h_cgroup)
+{
+	int node;
+
+	for_each_node(node)
+		kfree(h_cgroup->nodeinfo[node]);
+	kfree(h_cgroup);
+}
+
 static struct cgroup_subsys_state *
 hugetlb_cgroup_css_alloc(struct cgroup_subsys_state *parent_css)
 {
 	struct hugetlb_cgroup *parent_h_cgroup = hugetlb_cgroup_from_css(parent_css);
 	struct hugetlb_cgroup *h_cgroup;
+	int node;
+
+	h_cgroup = kzalloc(struct_size(h_cgroup, nodeinfo, nr_node_ids),
+			   GFP_KERNEL);
 
-	h_cgroup = kzalloc(sizeof(*h_cgroup), GFP_KERNEL);
 	if (!h_cgroup)
 		return ERR_PTR(-ENOMEM);
 
 	if (!parent_h_cgroup)
 		root_h_cgroup = h_cgroup;
 
+	/*
+	 * TODO: this routine can waste much memory for nodes which will
+	 * never be onlined. It's better to use memory hotplug callback
+	 * function.
+	 */
+	for_each_node(node) {
+		/* Set node_to_alloc to NUMA_NO_NODE for offline nodes. */
+		int node_to_alloc =
+			node_state(node, N_NORMAL_MEMORY) ? node : NUMA_NO_NODE;
+		h_cgroup->nodeinfo[node] =
+			kzalloc_node(sizeof(struct hugetlb_cgroup_per_node),
+				     GFP_KERNEL, node_to_alloc);
+		if (!h_cgroup->nodeinfo[node])
+			goto fail_alloc_nodeinfo;
+	}
+
 	hugetlb_cgroup_init(h_cgroup, parent_h_cgroup);
 	return &h_cgroup->css;
+
+fail_alloc_nodeinfo:
+	hugetlb_cgroup_free(h_cgroup);
+	return ERR_PTR(-ENOMEM);
 }
 
 static void hugetlb_cgroup_css_free(struct cgroup_subsys_state *css)
 {
-	struct hugetlb_cgroup *h_cgroup;
-
-	h_cgroup = hugetlb_cgroup_from_css(css);
-	kfree(h_cgroup);
+	hugetlb_cgroup_free(hugetlb_cgroup_from_css(css));
 }
 
-
 /*
  * Should be called with hugetlb_lock held.
  * Since we are holding hugetlb_lock, pages cannot get moved from
@@ -123,23 +192,23 @@ static void hugetlb_cgroup_css_free(struct cgroup_subsys_state *css)
  * cannot fail.
  */
 static void hugetlb_cgroup_move_parent(int idx, struct hugetlb_cgroup *h_cg,
-				       struct page *page)
+				       struct folio *folio)
 {
 	unsigned int nr_pages;
 	struct page_counter *counter;
-	struct hugetlb_cgroup *page_hcg;
+	struct hugetlb_cgroup *hcg;
 	struct hugetlb_cgroup *parent = parent_hugetlb_cgroup(h_cg);
 
-	page_hcg = hugetlb_cgroup_from_page(page);
+	hcg = hugetlb_cgroup_from_folio(folio);
 	/*
 	 * We can have pages in active list without any cgroup
 	 * ie, hugepage with less than 3 pages. We can safely
 	 * ignore those pages.
 	 */
-	if (!page_hcg || page_hcg != h_cg)
+	if (!hcg || hcg != h_cg)
 		goto out;
 
-	nr_pages = 1 << compound_order(page);
+	nr_pages = folio_nr_pages(folio);
 	if (!parent) {
 		parent = root_h_cgroup;
 		/* root has no limit */
@@ -149,7 +218,7 @@ static void hugetlb_cgroup_move_parent(int idx, struct hugetlb_cgroup *h_cg,
 	/* Take the pages off the local counter */
 	page_counter_cancel(counter, nr_pages);
 
-	set_hugetlb_cgroup(page, parent);
+	set_hugetlb_cgroup(folio, parent);
 out:
 	return;
 }
@@ -162,24 +231,36 @@ static void hugetlb_cgroup_css_offline(struct cgroup_subsys_state *css)
 {
 	struct hugetlb_cgroup *h_cg = hugetlb_cgroup_from_css(css);
 	struct hstate *h;
-	struct page *page;
-	int idx = 0;
+	struct folio *folio;
 
 	do {
 		for_each_hstate(h) {
-			spin_lock(&hugetlb_lock);
-			list_for_each_entry(page, &h->hugepage_activelist, lru)
-				hugetlb_cgroup_move_parent(idx, h_cg, page);
+			spin_lock_irq(&hugetlb_lock);
+			list_for_each_entry(folio, &h->hugepage_activelist, lru)
+				hugetlb_cgroup_move_parent(hstate_index(h), h_cg, folio);
 
-			spin_unlock(&hugetlb_lock);
-			idx++;
+			spin_unlock_irq(&hugetlb_lock);
 		}
 		cond_resched();
 	} while (hugetlb_cgroup_have_usage(h_cg));
 }
 
-int hugetlb_cgroup_charge_cgroup(int idx, unsigned long nr_pages,
-				 struct hugetlb_cgroup **ptr)
+static inline void hugetlb_event(struct hugetlb_cgroup *hugetlb, int idx,
+				 enum hugetlb_memory_event event)
+{
+	atomic_long_inc(&hugetlb->events_local[idx][event]);
+	cgroup_file_notify(&hugetlb->events_local_file[idx]);
+
+	do {
+		atomic_long_inc(&hugetlb->events[idx][event]);
+		cgroup_file_notify(&hugetlb->events_file[idx]);
+	} while ((hugetlb = parent_hugetlb_cgroup(hugetlb)) &&
+		 !hugetlb_cgroup_is_root(hugetlb));
+}
+
+static int __hugetlb_cgroup_charge_cgroup(int idx, unsigned long nr_pages,
+					  struct hugetlb_cgroup **ptr,
+					  bool rsvd)
 {
 	int ret = 0;
 	struct page_counter *counter;
@@ -187,126 +268,355 @@ int hugetlb_cgroup_charge_cgroup(int idx, unsigned long nr_pages,
 
 	if (hugetlb_cgroup_disabled())
 		goto done;
-	/*
-	 * We don't charge any cgroup if the compound page have less
-	 * than 3 pages.
-	 */
-	if (huge_page_order(&hstates[idx]) < HUGETLB_CGROUP_MIN_ORDER)
-		goto done;
 again:
 	rcu_read_lock();
 	h_cg = hugetlb_cgroup_from_task(current);
-	if (!css_tryget_online(&h_cg->css)) {
+	if (!css_tryget(&h_cg->css)) {
 		rcu_read_unlock();
 		goto again;
 	}
 	rcu_read_unlock();
 
-	if (!page_counter_try_charge(&h_cg->hugepage[idx], nr_pages, &counter))
+	if (!page_counter_try_charge(
+		    __hugetlb_cgroup_counter_from_cgroup(h_cg, idx, rsvd),
+		    nr_pages, &counter)) {
 		ret = -ENOMEM;
-	css_put(&h_cg->css);
+		hugetlb_event(h_cg, idx, HUGETLB_MAX);
+		css_put(&h_cg->css);
+		goto done;
+	}
+	/* Reservations take a reference to the css because they do not get
+	 * reparented.
+	 */
+	if (!rsvd)
+		css_put(&h_cg->css);
 done:
 	*ptr = h_cg;
 	return ret;
 }
 
+int hugetlb_cgroup_charge_cgroup(int idx, unsigned long nr_pages,
+				 struct hugetlb_cgroup **ptr)
+{
+	return __hugetlb_cgroup_charge_cgroup(idx, nr_pages, ptr, false);
+}
+
+int hugetlb_cgroup_charge_cgroup_rsvd(int idx, unsigned long nr_pages,
+				      struct hugetlb_cgroup **ptr)
+{
+	return __hugetlb_cgroup_charge_cgroup(idx, nr_pages, ptr, true);
+}
+
 /* Should be called with hugetlb_lock held */
-void hugetlb_cgroup_commit_charge(int idx, unsigned long nr_pages,
-				  struct hugetlb_cgroup *h_cg,
-				  struct page *page)
+static void __hugetlb_cgroup_commit_charge(int idx, unsigned long nr_pages,
+					   struct hugetlb_cgroup *h_cg,
+					   struct folio *folio, bool rsvd)
 {
 	if (hugetlb_cgroup_disabled() || !h_cg)
 		return;
+	lockdep_assert_held(&hugetlb_lock);
+	__set_hugetlb_cgroup(folio, h_cg, rsvd);
+	if (!rsvd) {
+		unsigned long usage =
+			h_cg->nodeinfo[folio_nid(folio)]->usage[idx];
+		/*
+		 * This write is not atomic due to fetching usage and writing
+		 * to it, but that's fine because we call this with
+		 * hugetlb_lock held anyway.
+		 */
+		WRITE_ONCE(h_cg->nodeinfo[folio_nid(folio)]->usage[idx],
+			   usage + nr_pages);
+	}
+}
 
-	set_hugetlb_cgroup(page, h_cg);
-	return;
+void hugetlb_cgroup_commit_charge(int idx, unsigned long nr_pages,
+				  struct hugetlb_cgroup *h_cg,
+				  struct folio *folio)
+{
+	__hugetlb_cgroup_commit_charge(idx, nr_pages, h_cg, folio, false);
+}
+
+void hugetlb_cgroup_commit_charge_rsvd(int idx, unsigned long nr_pages,
+				       struct hugetlb_cgroup *h_cg,
+				       struct folio *folio)
+{
+	__hugetlb_cgroup_commit_charge(idx, nr_pages, h_cg, folio, true);
 }
 
 /*
  * Should be called with hugetlb_lock held
  */
-void hugetlb_cgroup_uncharge_page(int idx, unsigned long nr_pages,
-				  struct page *page)
+static void __hugetlb_cgroup_uncharge_folio(int idx, unsigned long nr_pages,
+					   struct folio *folio, bool rsvd)
 {
 	struct hugetlb_cgroup *h_cg;
 
 	if (hugetlb_cgroup_disabled())
 		return;
 	lockdep_assert_held(&hugetlb_lock);
-	h_cg = hugetlb_cgroup_from_page(page);
+	h_cg = __hugetlb_cgroup_from_folio(folio, rsvd);
 	if (unlikely(!h_cg))
 		return;
-	set_hugetlb_cgroup(page, NULL);
-	page_counter_uncharge(&h_cg->hugepage[idx], nr_pages);
-	return;
+	__set_hugetlb_cgroup(folio, NULL, rsvd);
+
+	page_counter_uncharge(__hugetlb_cgroup_counter_from_cgroup(h_cg, idx,
+								   rsvd),
+			      nr_pages);
+
+	if (rsvd)
+		css_put(&h_cg->css);
+	else {
+		unsigned long usage =
+			h_cg->nodeinfo[folio_nid(folio)]->usage[idx];
+		/*
+		 * This write is not atomic due to fetching usage and writing
+		 * to it, but that's fine because we call this with
+		 * hugetlb_lock held anyway.
+		 */
+		WRITE_ONCE(h_cg->nodeinfo[folio_nid(folio)]->usage[idx],
+			   usage - nr_pages);
+	}
+}
+
+void hugetlb_cgroup_uncharge_folio(int idx, unsigned long nr_pages,
+				  struct folio *folio)
+{
+	__hugetlb_cgroup_uncharge_folio(idx, nr_pages, folio, false);
+}
+
+void hugetlb_cgroup_uncharge_folio_rsvd(int idx, unsigned long nr_pages,
+				       struct folio *folio)
+{
+	__hugetlb_cgroup_uncharge_folio(idx, nr_pages, folio, true);
+}
+
+static void __hugetlb_cgroup_uncharge_cgroup(int idx, unsigned long nr_pages,
+					     struct hugetlb_cgroup *h_cg,
+					     bool rsvd)
+{
+	if (hugetlb_cgroup_disabled() || !h_cg)
+		return;
+
+	page_counter_uncharge(__hugetlb_cgroup_counter_from_cgroup(h_cg, idx,
+								   rsvd),
+			      nr_pages);
+
+	if (rsvd)
+		css_put(&h_cg->css);
 }
 
 void hugetlb_cgroup_uncharge_cgroup(int idx, unsigned long nr_pages,
 				    struct hugetlb_cgroup *h_cg)
 {
-	if (hugetlb_cgroup_disabled() || !h_cg)
+	__hugetlb_cgroup_uncharge_cgroup(idx, nr_pages, h_cg, false);
+}
+
+void hugetlb_cgroup_uncharge_cgroup_rsvd(int idx, unsigned long nr_pages,
+					 struct hugetlb_cgroup *h_cg)
+{
+	__hugetlb_cgroup_uncharge_cgroup(idx, nr_pages, h_cg, true);
+}
+
+void hugetlb_cgroup_uncharge_counter(struct resv_map *resv, unsigned long start,
+				     unsigned long end)
+{
+	if (hugetlb_cgroup_disabled() || !resv || !resv->reservation_counter ||
+	    !resv->css)
 		return;
 
-	if (huge_page_order(&hstates[idx]) < HUGETLB_CGROUP_MIN_ORDER)
+	page_counter_uncharge(resv->reservation_counter,
+			      (end - start) * resv->pages_per_hpage);
+	css_put(resv->css);
+}
+
+void hugetlb_cgroup_uncharge_file_region(struct resv_map *resv,
+					 struct file_region *rg,
+					 unsigned long nr_pages,
+					 bool region_del)
+{
+	if (hugetlb_cgroup_disabled() || !resv || !rg || !nr_pages)
 		return;
 
-	page_counter_uncharge(&h_cg->hugepage[idx], nr_pages);
-	return;
+	if (rg->reservation_counter && resv->pages_per_hpage &&
+	    !resv->reservation_counter) {
+		page_counter_uncharge(rg->reservation_counter,
+				      nr_pages * resv->pages_per_hpage);
+		/*
+		 * Only do css_put(rg->css) when we delete the entire region
+		 * because one file_region must hold exactly one css reference.
+		 */
+		if (region_del)
+			css_put(rg->css);
+	}
 }
 
 enum {
 	RES_USAGE,
+	RES_RSVD_USAGE,
 	RES_LIMIT,
+	RES_RSVD_LIMIT,
 	RES_MAX_USAGE,
+	RES_RSVD_MAX_USAGE,
 	RES_FAILCNT,
+	RES_RSVD_FAILCNT,
 };
 
+static int hugetlb_cgroup_read_numa_stat(struct seq_file *seq, void *dummy)
+{
+	int nid;
+	struct cftype *cft = seq_cft(seq);
+	int idx = MEMFILE_IDX(cft->private);
+	bool legacy = !cgroup_subsys_on_dfl(hugetlb_cgrp_subsys);
+	struct hugetlb_cgroup *h_cg = hugetlb_cgroup_from_css(seq_css(seq));
+	struct cgroup_subsys_state *css;
+	unsigned long usage;
+
+	if (legacy) {
+		/* Add up usage across all nodes for the non-hierarchical total. */
+		usage = 0;
+		for_each_node_state(nid, N_MEMORY)
+			usage += READ_ONCE(h_cg->nodeinfo[nid]->usage[idx]);
+		seq_printf(seq, "total=%lu", usage * PAGE_SIZE);
+
+		/* Simply print the per-node usage for the non-hierarchical total. */
+		for_each_node_state(nid, N_MEMORY)
+			seq_printf(seq, " N%d=%lu", nid,
+				   READ_ONCE(h_cg->nodeinfo[nid]->usage[idx]) *
+					   PAGE_SIZE);
+		seq_putc(seq, '\n');
+	}
+
+	/*
+	 * The hierarchical total is pretty much the value recorded by the
+	 * counter, so use that.
+	 */
+	seq_printf(seq, "%stotal=%lu", legacy ? "hierarchical_" : "",
+		   page_counter_read(&h_cg->hugepage[idx]) * PAGE_SIZE);
+
+	/*
+	 * For each node, transverse the css tree to obtain the hierarchical
+	 * node usage.
+	 */
+	for_each_node_state(nid, N_MEMORY) {
+		usage = 0;
+		rcu_read_lock();
+		css_for_each_descendant_pre(css, &h_cg->css) {
+			usage += READ_ONCE(hugetlb_cgroup_from_css(css)
+						   ->nodeinfo[nid]
+						   ->usage[idx]);
+		}
+		rcu_read_unlock();
+		seq_printf(seq, " N%d=%lu", nid, usage * PAGE_SIZE);
+	}
+
+	seq_putc(seq, '\n');
+
+	return 0;
+}
+
 static u64 hugetlb_cgroup_read_u64(struct cgroup_subsys_state *css,
 				   struct cftype *cft)
 {
 	struct page_counter *counter;
+	struct page_counter *rsvd_counter;
 	struct hugetlb_cgroup *h_cg = hugetlb_cgroup_from_css(css);
 
 	counter = &h_cg->hugepage[MEMFILE_IDX(cft->private)];
+	rsvd_counter = &h_cg->rsvd_hugepage[MEMFILE_IDX(cft->private)];
 
 	switch (MEMFILE_ATTR(cft->private)) {
 	case RES_USAGE:
 		return (u64)page_counter_read(counter) * PAGE_SIZE;
+	case RES_RSVD_USAGE:
+		return (u64)page_counter_read(rsvd_counter) * PAGE_SIZE;
 	case RES_LIMIT:
-		return (u64)counter->limit * PAGE_SIZE;
+		return (u64)counter->max * PAGE_SIZE;
+	case RES_RSVD_LIMIT:
+		return (u64)rsvd_counter->max * PAGE_SIZE;
 	case RES_MAX_USAGE:
 		return (u64)counter->watermark * PAGE_SIZE;
+	case RES_RSVD_MAX_USAGE:
+		return (u64)rsvd_counter->watermark * PAGE_SIZE;
 	case RES_FAILCNT:
 		return counter->failcnt;
+	case RES_RSVD_FAILCNT:
+		return rsvd_counter->failcnt;
 	default:
 		BUG();
 	}
 }
 
+static int hugetlb_cgroup_read_u64_max(struct seq_file *seq, void *v)
+{
+	int idx;
+	u64 val;
+	struct cftype *cft = seq_cft(seq);
+	unsigned long limit;
+	struct page_counter *counter;
+	struct hugetlb_cgroup *h_cg = hugetlb_cgroup_from_css(seq_css(seq));
+
+	idx = MEMFILE_IDX(cft->private);
+	counter = &h_cg->hugepage[idx];
+
+	limit = round_down(PAGE_COUNTER_MAX,
+			   pages_per_huge_page(&hstates[idx]));
+
+	switch (MEMFILE_ATTR(cft->private)) {
+	case RES_RSVD_USAGE:
+		counter = &h_cg->rsvd_hugepage[idx];
+		fallthrough;
+	case RES_USAGE:
+		val = (u64)page_counter_read(counter);
+		seq_printf(seq, "%llu\n", val * PAGE_SIZE);
+		break;
+	case RES_RSVD_LIMIT:
+		counter = &h_cg->rsvd_hugepage[idx];
+		fallthrough;
+	case RES_LIMIT:
+		val = (u64)counter->max;
+		if (val == limit)
+			seq_puts(seq, "max\n");
+		else
+			seq_printf(seq, "%llu\n", val * PAGE_SIZE);
+		break;
+	default:
+		BUG();
+	}
+
+	return 0;
+}
+
 static DEFINE_MUTEX(hugetlb_limit_mutex);
 
 static ssize_t hugetlb_cgroup_write(struct kernfs_open_file *of,
-				    char *buf, size_t nbytes, loff_t off)
+				    char *buf, size_t nbytes, loff_t off,
+				    const char *max)
 {
 	int ret, idx;
 	unsigned long nr_pages;
 	struct hugetlb_cgroup *h_cg = hugetlb_cgroup_from_css(of_css(of));
+	bool rsvd = false;
 
 	if (hugetlb_cgroup_is_root(h_cg)) /* Can't set limit on root */
 		return -EINVAL;
 
 	buf = strstrip(buf);
-	ret = page_counter_memparse(buf, "-1", &nr_pages);
+	ret = page_counter_memparse(buf, max, &nr_pages);
 	if (ret)
 		return ret;
 
 	idx = MEMFILE_IDX(of_cft(of)->private);
-	nr_pages = round_down(nr_pages, 1 << huge_page_order(&hstates[idx]));
+	nr_pages = round_down(nr_pages, pages_per_huge_page(&hstates[idx]));
 
 	switch (MEMFILE_ATTR(of_cft(of)->private)) {
+	case RES_RSVD_LIMIT:
+		rsvd = true;
+		fallthrough;
 	case RES_LIMIT:
 		mutex_lock(&hugetlb_limit_mutex);
-		ret = page_counter_limit(&h_cg->hugepage[idx], nr_pages);
+		ret = page_counter_set_max(
+			__hugetlb_cgroup_counter_from_cgroup(h_cg, idx, rsvd),
+			nr_pages);
 		mutex_unlock(&hugetlb_limit_mutex);
 		break;
 	default:
@@ -316,22 +626,41 @@ static ssize_t hugetlb_cgroup_write(struct kernfs_open_file *of,
 	return ret ?: nbytes;
 }
 
+static ssize_t hugetlb_cgroup_write_legacy(struct kernfs_open_file *of,
+					   char *buf, size_t nbytes, loff_t off)
+{
+	return hugetlb_cgroup_write(of, buf, nbytes, off, "-1");
+}
+
+static ssize_t hugetlb_cgroup_write_dfl(struct kernfs_open_file *of,
+					char *buf, size_t nbytes, loff_t off)
+{
+	return hugetlb_cgroup_write(of, buf, nbytes, off, "max");
+}
+
 static ssize_t hugetlb_cgroup_reset(struct kernfs_open_file *of,
 				    char *buf, size_t nbytes, loff_t off)
 {
 	int ret = 0;
-	struct page_counter *counter;
+	struct page_counter *counter, *rsvd_counter;
 	struct hugetlb_cgroup *h_cg = hugetlb_cgroup_from_css(of_css(of));
 
 	counter = &h_cg->hugepage[MEMFILE_IDX(of_cft(of)->private)];
+	rsvd_counter = &h_cg->rsvd_hugepage[MEMFILE_IDX(of_cft(of)->private)];
 
 	switch (MEMFILE_ATTR(of_cft(of)->private)) {
 	case RES_MAX_USAGE:
 		page_counter_reset_watermark(counter);
 		break;
+	case RES_RSVD_MAX_USAGE:
+		page_counter_reset_watermark(rsvd_counter);
+		break;
 	case RES_FAILCNT:
 		counter->failcnt = 0;
 		break;
+	case RES_RSVD_FAILCNT:
+		rsvd_counter->failcnt = 0;
+		break;
 	default:
 		ret = -EINVAL;
 		break;
@@ -341,100 +670,259 @@ static ssize_t hugetlb_cgroup_reset(struct kernfs_open_file *of,
 
 static char *mem_fmt(char *buf, int size, unsigned long hsize)
 {
-	if (hsize >= (1UL << 30))
-		snprintf(buf, size, "%luGB", hsize >> 30);
-	else if (hsize >= (1UL << 20))
-		snprintf(buf, size, "%luMB", hsize >> 20);
+	if (hsize >= SZ_1G)
+		snprintf(buf, size, "%luGB", hsize / SZ_1G);
+	else if (hsize >= SZ_1M)
+		snprintf(buf, size, "%luMB", hsize / SZ_1M);
 	else
-		snprintf(buf, size, "%luKB", hsize >> 10);
+		snprintf(buf, size, "%luKB", hsize / SZ_1K);
 	return buf;
 }
 
-static void __init __hugetlb_cgroup_file_init(int idx)
+static int __hugetlb_events_show(struct seq_file *seq, bool local)
+{
+	int idx;
+	long max;
+	struct cftype *cft = seq_cft(seq);
+	struct hugetlb_cgroup *h_cg = hugetlb_cgroup_from_css(seq_css(seq));
+
+	idx = MEMFILE_IDX(cft->private);
+
+	if (local)
+		max = atomic_long_read(&h_cg->events_local[idx][HUGETLB_MAX]);
+	else
+		max = atomic_long_read(&h_cg->events[idx][HUGETLB_MAX]);
+
+	seq_printf(seq, "max %lu\n", max);
+
+	return 0;
+}
+
+static int hugetlb_events_show(struct seq_file *seq, void *v)
+{
+	return __hugetlb_events_show(seq, false);
+}
+
+static int hugetlb_events_local_show(struct seq_file *seq, void *v)
+{
+	return __hugetlb_events_show(seq, true);
+}
+
+static struct cftype hugetlb_dfl_tmpl[] = {
+	{
+		.name = "max",
+		.private = RES_LIMIT,
+		.seq_show = hugetlb_cgroup_read_u64_max,
+		.write = hugetlb_cgroup_write_dfl,
+		.flags = CFTYPE_NOT_ON_ROOT,
+	},
+	{
+		.name = "rsvd.max",
+		.private = RES_RSVD_LIMIT,
+		.seq_show = hugetlb_cgroup_read_u64_max,
+		.write = hugetlb_cgroup_write_dfl,
+		.flags = CFTYPE_NOT_ON_ROOT,
+	},
+	{
+		.name = "current",
+		.private = RES_USAGE,
+		.seq_show = hugetlb_cgroup_read_u64_max,
+		.flags = CFTYPE_NOT_ON_ROOT,
+	},
+	{
+		.name = "rsvd.current",
+		.private = RES_RSVD_USAGE,
+		.seq_show = hugetlb_cgroup_read_u64_max,
+		.flags = CFTYPE_NOT_ON_ROOT,
+	},
+	{
+		.name = "events",
+		.seq_show = hugetlb_events_show,
+		.file_offset = MEMFILE_OFFSET(struct hugetlb_cgroup, events_file[0]),
+		.flags = CFTYPE_NOT_ON_ROOT,
+	},
+	{
+		.name = "events.local",
+		.seq_show = hugetlb_events_local_show,
+		.file_offset = MEMFILE_OFFSET(struct hugetlb_cgroup, events_local_file[0]),
+		.flags = CFTYPE_NOT_ON_ROOT,
+	},
+	{
+		.name = "numa_stat",
+		.seq_show = hugetlb_cgroup_read_numa_stat,
+		.flags = CFTYPE_NOT_ON_ROOT,
+	},
+	/* don't need terminator here */
+};
+
+static struct cftype hugetlb_legacy_tmpl[] = {
+	{
+		.name = "limit_in_bytes",
+		.private = RES_LIMIT,
+		.read_u64 = hugetlb_cgroup_read_u64,
+		.write = hugetlb_cgroup_write_legacy,
+	},
+	{
+		.name = "rsvd.limit_in_bytes",
+		.private = RES_RSVD_LIMIT,
+		.read_u64 = hugetlb_cgroup_read_u64,
+		.write = hugetlb_cgroup_write_legacy,
+	},
+	{
+		.name = "usage_in_bytes",
+		.private = RES_USAGE,
+		.read_u64 = hugetlb_cgroup_read_u64,
+	},
+	{
+		.name = "rsvd.usage_in_bytes",
+		.private = RES_RSVD_USAGE,
+		.read_u64 = hugetlb_cgroup_read_u64,
+	},
+	{
+		.name = "max_usage_in_bytes",
+		.private = RES_MAX_USAGE,
+		.write = hugetlb_cgroup_reset,
+		.read_u64 = hugetlb_cgroup_read_u64,
+	},
+	{
+		.name = "rsvd.max_usage_in_bytes",
+		.private = RES_RSVD_MAX_USAGE,
+		.write = hugetlb_cgroup_reset,
+		.read_u64 = hugetlb_cgroup_read_u64,
+	},
+	{
+		.name = "failcnt",
+		.private = RES_FAILCNT,
+		.write = hugetlb_cgroup_reset,
+		.read_u64 = hugetlb_cgroup_read_u64,
+	},
+	{
+		.name = "rsvd.failcnt",
+		.private = RES_RSVD_FAILCNT,
+		.write = hugetlb_cgroup_reset,
+		.read_u64 = hugetlb_cgroup_read_u64,
+	},
+	{
+		.name = "numa_stat",
+		.seq_show = hugetlb_cgroup_read_numa_stat,
+	},
+	/* don't need terminator here */
+};
+
+static void __init
+hugetlb_cgroup_cfttypes_init(struct hstate *h, struct cftype *cft,
+			     struct cftype *tmpl, int tmpl_size)
 {
 	char buf[32];
-	struct cftype *cft;
-	struct hstate *h = &hstates[idx];
+	int i, idx = hstate_index(h);
 
 	/* format the size */
-	mem_fmt(buf, 32, huge_page_size(h));
-
-	/* Add the limit file */
-	cft = &h->cgroup_files[0];
-	snprintf(cft->name, MAX_CFTYPE_NAME, "%s.limit_in_bytes", buf);
-	cft->private = MEMFILE_PRIVATE(idx, RES_LIMIT);
-	cft->read_u64 = hugetlb_cgroup_read_u64;
-	cft->write = hugetlb_cgroup_write;
-
-	/* Add the usage file */
-	cft = &h->cgroup_files[1];
-	snprintf(cft->name, MAX_CFTYPE_NAME, "%s.usage_in_bytes", buf);
-	cft->private = MEMFILE_PRIVATE(idx, RES_USAGE);
-	cft->read_u64 = hugetlb_cgroup_read_u64;
-
-	/* Add the MAX usage file */
-	cft = &h->cgroup_files[2];
-	snprintf(cft->name, MAX_CFTYPE_NAME, "%s.max_usage_in_bytes", buf);
-	cft->private = MEMFILE_PRIVATE(idx, RES_MAX_USAGE);
-	cft->write = hugetlb_cgroup_reset;
-	cft->read_u64 = hugetlb_cgroup_read_u64;
-
-	/* Add the failcntfile */
-	cft = &h->cgroup_files[3];
-	snprintf(cft->name, MAX_CFTYPE_NAME, "%s.failcnt", buf);
-	cft->private  = MEMFILE_PRIVATE(idx, RES_FAILCNT);
-	cft->write = hugetlb_cgroup_reset;
-	cft->read_u64 = hugetlb_cgroup_read_u64;
-
-	/* NULL terminate the last cft */
-	cft = &h->cgroup_files[4];
-	memset(cft, 0, sizeof(*cft));
+	mem_fmt(buf, sizeof(buf), huge_page_size(h));
+
+	for (i = 0; i < tmpl_size; cft++, tmpl++, i++) {
+		*cft = *tmpl;
+		/* rebuild the name */
+		snprintf(cft->name, MAX_CFTYPE_NAME, "%s.%s", buf, tmpl->name);
+		/* rebuild the private */
+		cft->private = MEMFILE_PRIVATE(idx, tmpl->private);
+		/* rebuild the file_offset */
+		if (tmpl->file_offset) {
+			unsigned int offset = tmpl->file_offset;
+
+			cft->file_offset = MEMFILE_OFFSET0(offset) +
+					   MEMFILE_FIELD_SIZE(offset) * idx;
+		}
+
+		lockdep_register_key(&cft->lockdep_key);
+	}
+}
+
+static void __init __hugetlb_cgroup_file_dfl_init(struct hstate *h)
+{
+	int idx = hstate_index(h);
+
+	hugetlb_cgroup_cfttypes_init(h, dfl_files + idx * DFL_TMPL_SIZE,
+				     hugetlb_dfl_tmpl, DFL_TMPL_SIZE);
+}
+
+static void __init __hugetlb_cgroup_file_legacy_init(struct hstate *h)
+{
+	int idx = hstate_index(h);
+
+	hugetlb_cgroup_cfttypes_init(h, legacy_files + idx * LEGACY_TMPL_SIZE,
+				     hugetlb_legacy_tmpl, LEGACY_TMPL_SIZE);
+}
+
+static void __init __hugetlb_cgroup_file_init(struct hstate *h)
+{
+	__hugetlb_cgroup_file_dfl_init(h);
+	__hugetlb_cgroup_file_legacy_init(h);
+}
+
+static void __init __hugetlb_cgroup_file_pre_init(void)
+{
+	int cft_count;
+
+	cft_count = hugetlb_max_hstate * DFL_TMPL_SIZE + 1; /* add terminator */
+	dfl_files = kcalloc(cft_count, sizeof(struct cftype), GFP_KERNEL);
+	BUG_ON(!dfl_files);
+	cft_count = hugetlb_max_hstate * LEGACY_TMPL_SIZE + 1; /* add terminator */
+	legacy_files = kcalloc(cft_count, sizeof(struct cftype), GFP_KERNEL);
+	BUG_ON(!legacy_files);
+}
 
+static void __init __hugetlb_cgroup_file_post_init(void)
+{
+	WARN_ON(cgroup_add_dfl_cftypes(&hugetlb_cgrp_subsys,
+				       dfl_files));
 	WARN_ON(cgroup_add_legacy_cftypes(&hugetlb_cgrp_subsys,
-					  h->cgroup_files));
+					  legacy_files));
 }
 
 void __init hugetlb_cgroup_file_init(void)
 {
 	struct hstate *h;
 
-	for_each_hstate(h) {
-		/*
-		 * Add cgroup control files only if the huge page consists
-		 * of more than two normal pages. This is because we use
-		 * page[2].private for storing cgroup details.
-		 */
-		if (huge_page_order(h) >= HUGETLB_CGROUP_MIN_ORDER)
-			__hugetlb_cgroup_file_init(hstate_index(h));
-	}
+	__hugetlb_cgroup_file_pre_init();
+	for_each_hstate(h)
+		__hugetlb_cgroup_file_init(h);
+	__hugetlb_cgroup_file_post_init();
 }
 
 /*
  * hugetlb_lock will make sure a parallel cgroup rmdir won't happen
  * when we migrate hugepages
  */
-void hugetlb_cgroup_migrate(struct page *oldhpage, struct page *newhpage)
+void hugetlb_cgroup_migrate(struct folio *old_folio, struct folio *new_folio)
 {
 	struct hugetlb_cgroup *h_cg;
-	struct hstate *h = page_hstate(oldhpage);
+	struct hugetlb_cgroup *h_cg_rsvd;
+	struct hstate *h = folio_hstate(old_folio);
 
 	if (hugetlb_cgroup_disabled())
 		return;
 
-	VM_BUG_ON_PAGE(!PageHuge(oldhpage), oldhpage);
-	spin_lock(&hugetlb_lock);
-	h_cg = hugetlb_cgroup_from_page(oldhpage);
-	set_hugetlb_cgroup(oldhpage, NULL);
+	spin_lock_irq(&hugetlb_lock);
+	h_cg = hugetlb_cgroup_from_folio(old_folio);
+	h_cg_rsvd = hugetlb_cgroup_from_folio_rsvd(old_folio);
+	set_hugetlb_cgroup(old_folio, NULL);
+	set_hugetlb_cgroup_rsvd(old_folio, NULL);
 
 	/* move the h_cg details to new cgroup */
-	set_hugetlb_cgroup(newhpage, h_cg);
-	list_move(&newhpage->lru, &h->hugepage_activelist);
-	spin_unlock(&hugetlb_lock);
-	return;
+	set_hugetlb_cgroup(new_folio, h_cg);
+	set_hugetlb_cgroup_rsvd(new_folio, h_cg_rsvd);
+	list_move(&new_folio->lru, &h->hugepage_activelist);
+	spin_unlock_irq(&hugetlb_lock);
 }
 
+static struct cftype hugetlb_files[] = {
+	{} /* terminate */
+};
+
 struct cgroup_subsys hugetlb_cgrp_subsys = {
 	.css_alloc	= hugetlb_cgroup_css_alloc,
 	.css_offline	= hugetlb_cgroup_css_offline,
 	.css_free	= hugetlb_cgroup_css_free,
+	.dfl_cftypes	= hugetlb_files,
+	.legacy_cftypes	= hugetlb_files,
 };