/* SPDX-License-Identifier: GPL-2.0-or-later */

#ifndef __MM_MEMCONTROL_V1_H
#define __MM_MEMCONTROL_V1_H

#include <linux/cgroup-defs.h>

/* Cgroup v1 and v2 common declarations */

/*
 * Iteration constructs for visiting all cgroups (under a tree).  If
 * loops are exited prematurely (break), mem_cgroup_iter_break() must
 * be used for reference counting.
 */
#define for_each_mem_cgroup_tree(iter, root)            \
        for (iter = mem_cgroup_iter(root, NULL, NULL);  \
             iter != NULL;                              \
             iter = mem_cgroup_iter(root, iter, NULL))

#define for_each_mem_cgroup(iter)                       \
        for (iter = mem_cgroup_iter(NULL, NULL, NULL);  \
             iter != NULL;                              \
             iter = mem_cgroup_iter(NULL, iter, NULL))

void drain_all_stock(struct mem_cgroup *root_memcg);

unsigned long memcg_events(struct mem_cgroup *memcg, int event);
int memory_stat_show(struct seq_file *m, void *v);

void mem_cgroup_private_id_get_many(struct mem_cgroup *memcg, unsigned int n);
struct mem_cgroup *mem_cgroup_private_id_get_online(struct mem_cgroup *memcg);

/* Cgroup v1-specific declarations */
#ifdef CONFIG_MEMCG_V1

/* Whether legacy memory+swap accounting is active */
static inline bool do_memsw_account(void)
{
        return !cgroup_subsys_on_dfl(memory_cgrp_subsys);
}

unsigned long memcg_events_local(struct mem_cgroup *memcg, int event);
unsigned long memcg_page_state_local(struct mem_cgroup *memcg, int idx);
unsigned long memcg_page_state_local_output(struct mem_cgroup *memcg, int item);
bool memcg1_alloc_events(struct mem_cgroup *memcg);
void memcg1_free_events(struct mem_cgroup *memcg);

void memcg1_memcg_init(struct mem_cgroup *memcg);
void memcg1_remove_from_trees(struct mem_cgroup *memcg);

static inline void memcg1_soft_limit_reset(struct mem_cgroup *memcg)
{
        WRITE_ONCE(memcg->soft_limit, PAGE_COUNTER_MAX);
}

struct cgroup_taskset;
void memcg1_css_offline(struct mem_cgroup *memcg);

/* for encoding cft->private value on file */
enum res_type {
        _MEM,
        _MEMSWAP,
        _KMEM,
        _TCP,
};

bool memcg1_oom_prepare(struct mem_cgroup *memcg, bool *locked);
void memcg1_oom_finish(struct mem_cgroup *memcg, bool locked);
void memcg1_oom_recover(struct mem_cgroup *memcg);

void memcg1_commit_charge(struct folio *folio, struct mem_cgroup *memcg);
void memcg1_uncharge_batch(struct mem_cgroup *memcg, unsigned long pgpgout,
                           unsigned long nr_memory, int nid);

void memcg1_stat_format(struct mem_cgroup *memcg, struct seq_buf *s);

void memcg1_account_kmem(struct mem_cgroup *memcg, int nr_pages);
static inline bool memcg1_tcpmem_active(struct mem_cgroup *memcg)
{
        return memcg->tcpmem_active;
}
bool memcg1_charge_skmem(struct mem_cgroup *memcg, unsigned int nr_pages,
                         gfp_t gfp_mask);
static inline void memcg1_uncharge_skmem(struct mem_cgroup *memcg, unsigned int nr_pages)
{
        page_counter_uncharge(&memcg->tcpmem, nr_pages);
}

extern struct cftype memsw_files[];
extern struct cftype mem_cgroup_legacy_files[];

#else   /* CONFIG_MEMCG_V1 */

static inline bool do_memsw_account(void) { return false; }
static inline bool memcg1_alloc_events(struct mem_cgroup *memcg) { return true; }
static inline void memcg1_free_events(struct mem_cgroup *memcg) {}

static inline void memcg1_memcg_init(struct mem_cgroup *memcg) {}
static inline void memcg1_remove_from_trees(struct mem_cgroup *memcg) {}
static inline void memcg1_soft_limit_reset(struct mem_cgroup *memcg) {}
static inline void memcg1_css_offline(struct mem_cgroup *memcg) {}

static inline bool memcg1_oom_prepare(struct mem_cgroup *memcg, bool *locked) { return true; }
static inline void memcg1_oom_finish(struct mem_cgroup *memcg, bool locked) {}
static inline void memcg1_oom_recover(struct mem_cgroup *memcg) {}

static inline void memcg1_commit_charge(struct folio *folio,
                                        struct mem_cgroup *memcg) {}

static inline void memcg1_uncharge_batch(struct mem_cgroup *memcg,
                                         unsigned long pgpgout,
                                         unsigned long nr_memory, int nid) {}

static inline void memcg1_stat_format(struct mem_cgroup *memcg, struct seq_buf *s) {}

static inline void memcg1_account_kmem(struct mem_cgroup *memcg, int nr_pages) {}
static inline bool memcg1_tcpmem_active(struct mem_cgroup *memcg) { return false; }
static inline bool memcg1_charge_skmem(struct mem_cgroup *memcg, unsigned int nr_pages,
                                       gfp_t gfp_mask) { return true; }
static inline void memcg1_uncharge_skmem(struct mem_cgroup *memcg, unsigned int nr_pages) {}

#endif  /* CONFIG_MEMCG_V1 */

#endif  /* __MM_MEMCONTROL_V1_H */