/*-
 * Copyright (c) 2013-2015 Sandvine Inc.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#include <sys/param.h>
#include <sys/iov.h>
#include <sys/dnv.h>
#include <sys/nv.h>

#include <err.h>
#include <errno.h>
#include <fcntl.h>
#include <regex.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

#include "iovctl.h"

static void     config_action(const char *filename, int dryrun);
static void     delete_action(const char *device, int dryrun);
static void     print_schema(const char *device);

/*
 * Fetch the config schema from the kernel via ioctl.  This function has to
 * call the ioctl twice: the first returns the amount of memory that we need
 * to allocate for the schema, and the second actually fetches the schema.
 */
static nvlist_t *
get_schema(int fd)
{
        struct pci_iov_schema arg;
        nvlist_t *schema;
        int error;

        /* Do the ioctl() once to fetch the size of the schema. */
        arg.schema = NULL;
        arg.len = 0;
        arg.error = 0;
        error = ioctl(fd, IOV_GET_SCHEMA, &arg);
        if (error != 0)
                err(1, "Could not fetch size of config schema");

        arg.schema = malloc(arg.len);
        if (arg.schema == NULL)
                err(1, "Could not allocate %zu bytes for schema",
                    arg.len);

        /* Now do the ioctl() for real to get the schema. */
        error = ioctl(fd, IOV_GET_SCHEMA, &arg);
        if (error != 0 || arg.error != 0) {
                if (arg.error != 0)
                        errno = arg.error;
                err(1, "Could not fetch config schema");
        }

        schema = nvlist_unpack(arg.schema, arg.len, NV_FLAG_IGNORE_CASE);
        if (schema == NULL)
                err(1, "Could not unpack schema");

        free(arg.schema);
        return (schema);
}

/*
 * Call the ioctl that activates SR-IOV and creates the VFs.
 */
static void
config_iov(int fd, const char *dev_name, const nvlist_t *config, int dryrun)
{
        struct pci_iov_arg arg;
        int error;

        arg.config = nvlist_pack(config, &arg.len);
        if (arg.config == NULL)
                err(1, "Could not pack configuration");

        if (dryrun) {
                printf("Would enable SR-IOV on device '%s'.\n", dev_name);
                printf(
                    "The following configuration parameters would be used:\n");
                nvlist_fdump(config, stdout);
                printf(
                "The configuration parameters consume %zu bytes when packed.\n",
                    arg.len);
        } else {
                error = ioctl(fd, IOV_CONFIG, &arg);
                if (error != 0)
                        err(1, "Failed to configure SR-IOV");
        }

        free(arg.config);
}

static int
open_device(const char *dev_name)
{
        char *dev;
        int fd;
        size_t copied, size;
        long path_max;

        path_max = pathconf("/dev", _PC_PATH_MAX);
        if (path_max < 0)
                err(1, "Could not get maximum path length");

        size = path_max;
        dev = malloc(size);
        if (dev == NULL)
                err(1, "Could not allocate memory for device path");

        if (dev_name[0] == '/')
                copied = strlcpy(dev, dev_name, size);
        else
                copied = snprintf(dev, size, "/dev/iov/%s", dev_name);

        /* >= to account for null terminator. */
        if (copied >= size)
                errx(1, "Provided file name too long");

        fd = open(dev, O_RDWR);
        if (fd < 0)
                err(1, "Could not open device '%s'", dev);

        free(dev);
        return (fd);
}

static void
usage(void)
{

        warnx("Usage: iovctl -C -f <config file> [-n]");
        warnx("       iovctl -D [-d <PF device> | -f <config file>] [-n]");
        warnx("       iovctl -S [-d <PF device> | -f <config file>]");
        exit(1);

}

enum main_action {
        NONE,
        CONFIG,
        DELETE,
        PRINT_SCHEMA,
};

int
main(int argc, char **argv)
{
        char *device;
        const char *filename;
        int ch, dryrun;
        enum main_action action;

        device = NULL;
        filename = NULL;
        dryrun = 0;
        action = NONE;

        while ((ch = getopt(argc, argv, "Cd:Df:nS")) != -1) {
                switch (ch) {
                case 'C':
                        if (action != NONE) {
                                warnx(
                                   "Only one of -C, -D or -S may be specified");
                                usage();
                        }
                        action = CONFIG;
                        break;
                case 'd':
                        device = strdup(optarg);
                        break;
                case 'D':
                        if (action != NONE) {
                                warnx(
                                   "Only one of -C, -D or -S may be specified");
                                usage();
                        }
                        action = DELETE;
                        break;
                case 'f':
                        filename = optarg;
                        break;
                case 'n':
                        dryrun = 1;
                        break;
                case 'S':
                        if (action != NONE) {
                                warnx(
                                   "Only one of -C, -D or -S may be specified");
                                usage();
                        }
                        action = PRINT_SCHEMA;
                        break;
                case '?':
                        warnx("Unrecognized argument '-%c'\n", optopt);
                        usage();
                        break;
                }
        }

        if (device != NULL && filename != NULL) {
                warnx("Only one of the -d and -f flags may be specified");
                usage();
        }

        if (device == NULL && filename == NULL  && action != CONFIG) {
                warnx("Either the -d or -f flag must be specified");
                usage();
        }

        switch (action) {
        case CONFIG:
                if (device != NULL) {
                        warnx("-d flag cannot be used with the -C flag");
                        usage();
                }
                if (filename == NULL) {
                        warnx("The -f flag must be specified");
                        usage();
                }
                config_action(filename, dryrun);
                break;
        case DELETE:
                if (device == NULL)
                        device = find_device(filename);
                delete_action(device, dryrun);
                free(device);
                break;
        case PRINT_SCHEMA:
                if (dryrun) {
                        warnx("-n flag cannot be used with the -S flag");
                        usage();
                }
                if (device == NULL)
                        device = find_device(filename);
                print_schema(device);
                free(device);
                break;
        default:
                usage();
                break;
        }

        exit(0);
}

static void
config_action(const char *filename, int dryrun)
{
        char *dev;
        nvlist_t *schema, *config;
        int fd;

        dev = find_device(filename);
        fd = open(dev, O_RDWR);
        if (fd < 0)
                err(1, "Could not open device '%s'", dev);

        schema = get_schema(fd);
        config = parse_config_file(filename, schema);
        if (config == NULL)
                errx(1, "Could not parse config");

        config_iov(fd, dev, config, dryrun);

        nvlist_destroy(config);
        nvlist_destroy(schema);
        free(dev);
        close(fd);
}

static void
delete_action(const char *dev_name, int dryrun)
{
        int fd, error;

        fd = open_device(dev_name);

        if (dryrun)
                printf("Would attempt to delete all VF children of '%s'\n",
                    dev_name);
        else {
                error = ioctl(fd, IOV_DELETE);
                if (error != 0)
                        err(1, "Failed to delete VFs");
        }

        close(fd);
}

static void
print_default_value(const nvlist_t *parameter, const char *type)
{
        const uint8_t *mac;
        size_t size;

        if (strcasecmp(type, "bool") == 0)
                printf(" (default = %s)",
                    nvlist_get_bool(parameter, DEFAULT_SCHEMA_NAME) ? "true" :
                    "false");
        else if (strcasecmp(type, "string") == 0)
                printf(" (default = %s)",
                    nvlist_get_string(parameter, DEFAULT_SCHEMA_NAME));
        else if (strcasecmp(type, "uint8_t") == 0)
                printf(" (default = %ju)",
                    (uintmax_t)nvlist_get_number(parameter,
                    DEFAULT_SCHEMA_NAME));
        else if (strcasecmp(type, "uint16_t") == 0)
                printf(" (default = %ju)",
                    (uintmax_t)nvlist_get_number(parameter,
                    DEFAULT_SCHEMA_NAME));
        else if (strcasecmp(type, "uint32_t") == 0)
                printf(" (default = %ju)",
                    (uintmax_t)nvlist_get_number(parameter,
                    DEFAULT_SCHEMA_NAME));
        else if (strcasecmp(type, "uint64_t") == 0)
                printf(" (default = %ju)",
                    (uintmax_t)nvlist_get_number(parameter,
                    DEFAULT_SCHEMA_NAME));
        else if (strcasecmp(type, "unicast-mac") == 0) {
                mac = nvlist_get_binary(parameter, DEFAULT_SCHEMA_NAME, &size);
                printf(" (default = %02x:%02x:%02x:%02x:%02x:%02x)", mac[0],
                    mac[1], mac[2], mac[3], mac[4], mac[5]);
        } else if (strcasecmp(type, "vlan") == 0) {
                uint16_t vlan = nvlist_get_number(parameter, DEFAULT_SCHEMA_NAME);
                if (vlan == VF_VLAN_TRUNK)
                        printf(" (default = trunk)");
                else
                        printf(" (default = %d)", vlan);
        } else
                errx(1, "Unexpected type in schema: '%s'", type);
}

static void
print_subsystem_schema(const nvlist_t * subsystem_schema)
{
        const char *name, *type;
        const nvlist_t *parameter;
        void *it;
        int nvtype;

        it = NULL;
        while ((name = nvlist_next(subsystem_schema, &nvtype, &it)) != NULL) {
                parameter = nvlist_get_nvlist(subsystem_schema, name);
                type = nvlist_get_string(parameter, TYPE_SCHEMA_NAME);

                printf("\t%s : %s", name, type);
                if (dnvlist_get_bool(parameter, REQUIRED_SCHEMA_NAME, false))
                        printf(" (required)");
                else if (nvlist_exists(parameter, DEFAULT_SCHEMA_NAME))
                        print_default_value(parameter, type);
                else
                        printf(" (optional)");
                printf("\n");
        }
}

static void
print_schema(const char *dev_name)
{
        nvlist_t *schema;
        const nvlist_t *iov_schema, *driver_schema, *pf_schema, *vf_schema;
        int fd;

        fd = open_device(dev_name);
        schema = get_schema(fd);

        pf_schema = nvlist_get_nvlist(schema, PF_CONFIG_NAME);
        iov_schema = nvlist_get_nvlist(pf_schema, IOV_CONFIG_NAME);
        driver_schema = nvlist_get_nvlist(pf_schema, DRIVER_CONFIG_NAME);
        printf(
"The following configuration parameters may be configured on the PF:\n");
        print_subsystem_schema(iov_schema);
        print_subsystem_schema(driver_schema);

        vf_schema = nvlist_get_nvlist(schema, VF_SCHEMA_NAME);
        iov_schema = nvlist_get_nvlist(vf_schema, IOV_CONFIG_NAME);
        driver_schema = nvlist_get_nvlist(vf_schema, DRIVER_CONFIG_NAME);
        printf(
"\nThe following configuration parameters may be configured on a VF:\n");
        print_subsystem_schema(iov_schema);
        print_subsystem_schema(driver_schema);

        nvlist_destroy(schema);
        close(fd);
}