// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright (C) 2011-2017, Red Hat Inc, Arnaldo Carvalho de Melo <acme@redhat.com>
 *
 * Parts came from evlist.c builtin-{top,stat,record}.c, see those files for further
 * copyright notes.
 */

#include <sys/mman.h>
#include <errno.h>
#include <inttypes.h>
#include <asm/bug.h>
#include <linux/zalloc.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h> // sysconf()
#include <perf/mmap.h>
#ifdef HAVE_LIBNUMA_SUPPORT
#include <numaif.h>
#endif
#include "cpumap.h"
#include "debug.h"
#include "event.h"
#include "mmap.h"
#include "../perf.h"
#include <internal/lib.h> /* page_size */
#include <linux/bitmap.h>

#define MASK_SIZE 1023
void mmap_cpu_mask__scnprintf(struct mmap_cpu_mask *mask, const char *tag)
{
        char buf[MASK_SIZE + 1];
        size_t len;

        len = bitmap_scnprintf(mask->bits, mask->nbits, buf, MASK_SIZE);
        buf[len] = '\0';
        pr_debug("%p: %s mask[%zd]: %s\n", mask, tag, mask->nbits, buf);
}

size_t mmap__mmap_len(struct mmap *map)
{
        return perf_mmap__mmap_len(&map->core);
}

int __weak auxtrace_mmap__mmap(struct auxtrace_mmap *mm __maybe_unused,
                               struct auxtrace_mmap_params *mp __maybe_unused,
                               void *userpg __maybe_unused,
                               int fd __maybe_unused)
{
        return 0;
}

void __weak auxtrace_mmap__munmap(struct auxtrace_mmap *mm __maybe_unused)
{
}

void __weak auxtrace_mmap_params__init(struct auxtrace_mmap_params *mp __maybe_unused,
                                       off_t auxtrace_offset __maybe_unused,
                                       unsigned int auxtrace_pages __maybe_unused,
                                       bool auxtrace_overwrite __maybe_unused)
{
}

void __weak auxtrace_mmap_params__set_idx(struct auxtrace_mmap_params *mp __maybe_unused,
                                          struct evlist *evlist __maybe_unused,
                                          struct evsel *evsel __maybe_unused,
                                          int idx __maybe_unused)
{
}

#ifdef HAVE_AIO_SUPPORT
static int perf_mmap__aio_enabled(struct mmap *map)
{
        return map->aio.nr_cblocks > 0;
}

#ifdef HAVE_LIBNUMA_SUPPORT
static int perf_mmap__aio_alloc(struct mmap *map, int idx)
{
        map->aio.data[idx] = mmap(NULL, mmap__mmap_len(map), PROT_READ|PROT_WRITE,
                                  MAP_PRIVATE|MAP_ANONYMOUS, 0, 0);
        if (map->aio.data[idx] == MAP_FAILED) {
                map->aio.data[idx] = NULL;
                return -1;
        }

        return 0;
}

static void perf_mmap__aio_free(struct mmap *map, int idx)
{
        if (map->aio.data[idx]) {
                munmap(map->aio.data[idx], mmap__mmap_len(map));
                map->aio.data[idx] = NULL;
        }
}

static int perf_mmap__aio_bind(struct mmap *map, int idx, struct perf_cpu cpu, int affinity)
{
        void *data;
        size_t mmap_len;
        unsigned long *node_mask;
        unsigned long node_index;
        int err = 0;

        if (affinity != PERF_AFFINITY_SYS && cpu__max_node() > 1) {
                data = map->aio.data[idx];
                mmap_len = mmap__mmap_len(map);
                node_index = cpu__get_node(cpu);
                node_mask = bitmap_zalloc(node_index + 1);
                if (!node_mask) {
                        pr_err("Failed to allocate node mask for mbind: error %m\n");
                        return -1;
                }
                __set_bit(node_index, node_mask);
                if (mbind(data, mmap_len, MPOL_BIND, node_mask, node_index + 1 + 1, 0)) {
                        pr_err("Failed to bind [%p-%p] AIO buffer to node %lu: error %m\n",
                                data, data + mmap_len, node_index);
                        err = -1;
                }
                bitmap_free(node_mask);
        }

        return err;
}
#else /* !HAVE_LIBNUMA_SUPPORT */
static int perf_mmap__aio_alloc(struct mmap *map, int idx)
{
        map->aio.data[idx] = malloc(mmap__mmap_len(map));
        if (map->aio.data[idx] == NULL)
                return -1;

        return 0;
}

static void perf_mmap__aio_free(struct mmap *map, int idx)
{
        zfree(&(map->aio.data[idx]));
}

static int perf_mmap__aio_bind(struct mmap *map __maybe_unused, int idx __maybe_unused,
                struct perf_cpu cpu __maybe_unused, int affinity __maybe_unused)
{
        return 0;
}
#endif

static int perf_mmap__aio_mmap(struct mmap *map, struct mmap_params *mp)
{
        int delta_max, i, prio, ret;

        map->aio.nr_cblocks = mp->nr_cblocks;
        if (map->aio.nr_cblocks) {
                map->aio.aiocb = calloc(map->aio.nr_cblocks, sizeof(struct aiocb *));
                if (!map->aio.aiocb) {
                        pr_debug2("failed to allocate aiocb for data buffer, error %m\n");
                        return -1;
                }
                map->aio.cblocks = calloc(map->aio.nr_cblocks, sizeof(struct aiocb));
                if (!map->aio.cblocks) {
                        pr_debug2("failed to allocate cblocks for data buffer, error %m\n");
                        return -1;
                }
                map->aio.data = calloc(map->aio.nr_cblocks, sizeof(void *));
                if (!map->aio.data) {
                        pr_debug2("failed to allocate data buffer, error %m\n");
                        return -1;
                }
                delta_max = sysconf(_SC_AIO_PRIO_DELTA_MAX);
                for (i = 0; i < map->aio.nr_cblocks; ++i) {
                        ret = perf_mmap__aio_alloc(map, i);
                        if (ret == -1) {
                                pr_debug2("failed to allocate data buffer area, error %m");
                                return -1;
                        }
                        ret = perf_mmap__aio_bind(map, i, map->core.cpu, mp->affinity);
                        if (ret == -1)
                                return -1;
                        /*
                         * Use cblock.aio_fildes value different from -1
                         * to denote started aio write operation on the
                         * cblock so it requires explicit record__aio_sync()
                         * call prior the cblock may be reused again.
                         */
                        map->aio.cblocks[i].aio_fildes = -1;
                        /*
                         * Allocate cblocks with priority delta to have
                         * faster aio write system calls because queued requests
                         * are kept in separate per-prio queues and adding
                         * a new request will iterate thru shorter per-prio
                         * list. Blocks with numbers higher than
                         *  _SC_AIO_PRIO_DELTA_MAX go with priority 0.
                         */
                        prio = delta_max - i;
                        map->aio.cblocks[i].aio_reqprio = prio >= 0 ? prio : 0;
                }
        }

        return 0;
}

static void perf_mmap__aio_munmap(struct mmap *map)
{
        int i;

        for (i = 0; i < map->aio.nr_cblocks; ++i)
                perf_mmap__aio_free(map, i);
        if (map->aio.data)
                zfree(&map->aio.data);
        zfree(&map->aio.cblocks);
        zfree(&map->aio.aiocb);
}
#else /* !HAVE_AIO_SUPPORT */
static int perf_mmap__aio_enabled(struct mmap *map __maybe_unused)
{
        return 0;
}

static int perf_mmap__aio_mmap(struct mmap *map __maybe_unused,
                               struct mmap_params *mp __maybe_unused)
{
        return 0;
}

static void perf_mmap__aio_munmap(struct mmap *map __maybe_unused)
{
}
#endif

void mmap__munmap(struct mmap *map)
{
        bitmap_free(map->affinity_mask.bits);

        zstd_fini(&map->zstd_data);

        perf_mmap__aio_munmap(map);
        if (map->data != NULL) {
                munmap(map->data, mmap__mmap_len(map));
                map->data = NULL;
        }
        auxtrace_mmap__munmap(&map->auxtrace_mmap);
}

static void build_node_mask(int node, struct mmap_cpu_mask *mask)
{
        int idx, nr_cpus;
        struct perf_cpu cpu;
        struct perf_cpu_map *cpu_map = cpu_map__online();

        if (!cpu_map)
                return;

        nr_cpus = perf_cpu_map__nr(cpu_map);
        for (idx = 0; idx < nr_cpus; idx++) {
                cpu = perf_cpu_map__cpu(cpu_map, idx); /* map c index to online cpu index */
                if (cpu__get_node(cpu) == node)
                        __set_bit(cpu.cpu, mask->bits);
        }
        perf_cpu_map__put(cpu_map);
}

static int perf_mmap__setup_affinity_mask(struct mmap *map, struct mmap_params *mp)
{
        map->affinity_mask.nbits = cpu__max_cpu().cpu;
        map->affinity_mask.bits = bitmap_zalloc(map->affinity_mask.nbits);
        if (!map->affinity_mask.bits)
                return -1;

        if (mp->affinity == PERF_AFFINITY_NODE && cpu__max_node() > 1)
                build_node_mask(cpu__get_node(map->core.cpu), &map->affinity_mask);
        else if (mp->affinity == PERF_AFFINITY_CPU)
                __set_bit(map->core.cpu.cpu, map->affinity_mask.bits);

        return 0;
}

int mmap__mmap(struct mmap *map, struct mmap_params *mp, int fd, struct perf_cpu cpu)
{
        if (perf_mmap__mmap(&map->core, &mp->core, fd, cpu)) {
                pr_debug2("failed to mmap perf event ring buffer, error %d\n",
                          errno);
                return -1;
        }

        if (mp->affinity != PERF_AFFINITY_SYS &&
                perf_mmap__setup_affinity_mask(map, mp)) {
                pr_debug2("failed to alloc mmap affinity mask, error %d\n",
                          errno);
                return -1;
        }

        if (verbose == 2)
                mmap_cpu_mask__scnprintf(&map->affinity_mask, "mmap");

        map->core.flush = mp->flush;

        if (zstd_init(&map->zstd_data, mp->comp_level)) {
                pr_debug2("failed to init mmap compressor, error %d\n", errno);
                return -1;
        }

        if (mp->comp_level && !perf_mmap__aio_enabled(map)) {
                map->data = mmap(NULL, mmap__mmap_len(map), PROT_READ|PROT_WRITE,
                                 MAP_PRIVATE|MAP_ANONYMOUS, 0, 0);
                if (map->data == MAP_FAILED) {
                        pr_debug2("failed to mmap data buffer, error %d\n",
                                        errno);
                        map->data = NULL;
                        return -1;
                }
        }

        if (auxtrace_mmap__mmap(&map->auxtrace_mmap,
                                &mp->auxtrace_mp, map->core.base, fd))
                return -1;

        return perf_mmap__aio_mmap(map, mp);
}

int perf_mmap__push(struct mmap *md, void *to,
                    int push(struct mmap *map, void *to, void *buf, size_t size))
{
        u64 head = perf_mmap__read_head(&md->core);
        unsigned char *data = md->core.base + page_size;
        unsigned long size;
        void *buf;
        int rc = 0;

        rc = perf_mmap__read_init(&md->core);
        if (rc < 0)
                return (rc == -EAGAIN) ? 1 : -1;

        size = md->core.end - md->core.start;

        if ((md->core.start & md->core.mask) + size != (md->core.end & md->core.mask)) {
                buf = &data[md->core.start & md->core.mask];
                size = md->core.mask + 1 - (md->core.start & md->core.mask);
                md->core.start += size;

                if (push(md, to, buf, size) < 0) {
                        rc = -1;
                        goto out;
                }
        }

        buf = &data[md->core.start & md->core.mask];
        size = md->core.end - md->core.start;
        md->core.start += size;

        if (push(md, to, buf, size) < 0) {
                rc = -1;
                goto out;
        }

        md->core.prev = head;
        perf_mmap__consume(&md->core);
out:
        return rc;
}