bonding: convert primary_slave to use RCU

[mirror_ubuntu-bionic-kernel.git] / drivers / net / bonding / bond_options.c

/*
 * drivers/net/bond/bond_options.c - bonding options
 * Copyright (c) 2013 Jiri Pirko <jiri@resnulli.us>
 * Copyright (c) 2013 Scott Feldman <sfeldma@cumulusnetworks.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 */

#include <linux/errno.h>
#include <linux/if.h>
#include <linux/netdevice.h>
#include <linux/spinlock.h>
#include <linux/rcupdate.h>
#include <linux/ctype.h>
#include <linux/inet.h>
#include "bonding.h"

static int bond_option_active_slave_set(struct bonding *bond,
                                        const struct bond_opt_value *newval);
static int bond_option_miimon_set(struct bonding *bond,
                                  const struct bond_opt_value *newval);
static int bond_option_updelay_set(struct bonding *bond,
                                   const struct bond_opt_value *newval);
static int bond_option_downdelay_set(struct bonding *bond,
                                     const struct bond_opt_value *newval);
static int bond_option_use_carrier_set(struct bonding *bond,
                                       const struct bond_opt_value *newval);
static int bond_option_arp_interval_set(struct bonding *bond,
                                        const struct bond_opt_value *newval);
static int bond_option_arp_ip_target_add(struct bonding *bond, __be32 target);
static int bond_option_arp_ip_target_rem(struct bonding *bond, __be32 target);
static int bond_option_arp_ip_targets_set(struct bonding *bond,
                                          const struct bond_opt_value *newval);
static int bond_option_arp_validate_set(struct bonding *bond,
                                        const struct bond_opt_value *newval);
static int bond_option_arp_all_targets_set(struct bonding *bond,
                                           const struct bond_opt_value *newval);
static int bond_option_primary_set(struct bonding *bond,
                                   const struct bond_opt_value *newval);
static int bond_option_primary_reselect_set(struct bonding *bond,
                                            const struct bond_opt_value *newval);
static int bond_option_fail_over_mac_set(struct bonding *bond,
                                         const struct bond_opt_value *newval);
static int bond_option_xmit_hash_policy_set(struct bonding *bond,
                                            const struct bond_opt_value *newval);
static int bond_option_resend_igmp_set(struct bonding *bond,
                                       const struct bond_opt_value *newval);
static int bond_option_num_peer_notif_set(struct bonding *bond,
                                          const struct bond_opt_value *newval);
static int bond_option_all_slaves_active_set(struct bonding *bond,
                                             const struct bond_opt_value *newval);
static int bond_option_min_links_set(struct bonding *bond,
                                     const struct bond_opt_value *newval);
static int bond_option_lp_interval_set(struct bonding *bond,
                                       const struct bond_opt_value *newval);
static int bond_option_pps_set(struct bonding *bond,
                               const struct bond_opt_value *newval);
static int bond_option_lacp_rate_set(struct bonding *bond,
                                     const struct bond_opt_value *newval);
static int bond_option_ad_select_set(struct bonding *bond,
                                     const struct bond_opt_value *newval);
static int bond_option_queue_id_set(struct bonding *bond,
                                    const struct bond_opt_value *newval);
static int bond_option_mode_set(struct bonding *bond,
                                const struct bond_opt_value *newval);
static int bond_option_slaves_set(struct bonding *bond,
                                  const struct bond_opt_value *newval);
static int bond_option_tlb_dynamic_lb_set(struct bonding *bond,
                                  const struct bond_opt_value *newval);


static const struct bond_opt_value bond_mode_tbl[] = {
        { "balance-rr",    BOND_MODE_ROUNDROBIN,   BOND_VALFLAG_DEFAULT},
        { "active-backup", BOND_MODE_ACTIVEBACKUP, 0},
        { "balance-xor",   BOND_MODE_XOR,          0},
        { "broadcast",     BOND_MODE_BROADCAST,    0},
        { "802.3ad",       BOND_MODE_8023AD,       0},
        { "balance-tlb",   BOND_MODE_TLB,          0},
        { "balance-alb",   BOND_MODE_ALB,          0},
        { NULL,            -1,                     0},
};

static const struct bond_opt_value bond_pps_tbl[] = {
        { "default", 1,         BOND_VALFLAG_DEFAULT},
        { "maxval",  USHRT_MAX, BOND_VALFLAG_MAX},
        { NULL,      -1,        0},
};

static const struct bond_opt_value bond_xmit_hashtype_tbl[] = {
        { "layer2",   BOND_XMIT_POLICY_LAYER2, BOND_VALFLAG_DEFAULT},
        { "layer3+4", BOND_XMIT_POLICY_LAYER34, 0},
        { "layer2+3", BOND_XMIT_POLICY_LAYER23, 0},
        { "encap2+3", BOND_XMIT_POLICY_ENCAP23, 0},
        { "encap3+4", BOND_XMIT_POLICY_ENCAP34, 0},
        { NULL,       -1,                       0},
};

static const struct bond_opt_value bond_arp_validate_tbl[] = {
        { "none",               BOND_ARP_VALIDATE_NONE,         BOND_VALFLAG_DEFAULT},
        { "active",             BOND_ARP_VALIDATE_ACTIVE,       0},
        { "backup",             BOND_ARP_VALIDATE_BACKUP,       0},
        { "all",                BOND_ARP_VALIDATE_ALL,          0},
        { "filter",             BOND_ARP_FILTER,                0},
        { "filter_active",      BOND_ARP_FILTER_ACTIVE,         0},
        { "filter_backup",      BOND_ARP_FILTER_BACKUP,         0},
        { NULL,                 -1,                             0},
};

static const struct bond_opt_value bond_arp_all_targets_tbl[] = {
        { "any", BOND_ARP_TARGETS_ANY, BOND_VALFLAG_DEFAULT},
        { "all", BOND_ARP_TARGETS_ALL, 0},
        { NULL,  -1,                   0},
};

static const struct bond_opt_value bond_fail_over_mac_tbl[] = {
        { "none",   BOND_FOM_NONE,   BOND_VALFLAG_DEFAULT},
        { "active", BOND_FOM_ACTIVE, 0},
        { "follow", BOND_FOM_FOLLOW, 0},
        { NULL,     -1,              0},
};

static const struct bond_opt_value bond_intmax_tbl[] = {
        { "off",     0,       BOND_VALFLAG_DEFAULT},
        { "maxval",  INT_MAX, BOND_VALFLAG_MAX},
        { NULL,      -1,      0}
};

static const struct bond_opt_value bond_lacp_rate_tbl[] = {
        { "slow", AD_LACP_SLOW, 0},
        { "fast", AD_LACP_FAST, 0},
        { NULL,   -1,           0},
};

static const struct bond_opt_value bond_ad_select_tbl[] = {
        { "stable",    BOND_AD_STABLE,    BOND_VALFLAG_DEFAULT},
        { "bandwidth", BOND_AD_BANDWIDTH, 0},
        { "count",     BOND_AD_COUNT,     0},
        { NULL,        -1,                0},
};

static const struct bond_opt_value bond_num_peer_notif_tbl[] = {
        { "off",     0,   0},
        { "maxval",  255, BOND_VALFLAG_MAX},
        { "default", 1,   BOND_VALFLAG_DEFAULT},
        { NULL,      -1,  0}
};

static const struct bond_opt_value bond_primary_reselect_tbl[] = {
        { "always",  BOND_PRI_RESELECT_ALWAYS,  BOND_VALFLAG_DEFAULT},
        { "better",  BOND_PRI_RESELECT_BETTER,  0},
        { "failure", BOND_PRI_RESELECT_FAILURE, 0},
        { NULL,      -1},
};

static const struct bond_opt_value bond_use_carrier_tbl[] = {
        { "off", 0,  0},
        { "on",  1,  BOND_VALFLAG_DEFAULT},
        { NULL,  -1, 0}
};

static const struct bond_opt_value bond_all_slaves_active_tbl[] = {
        { "off", 0,  BOND_VALFLAG_DEFAULT},
        { "on",  1,  0},
        { NULL,  -1, 0}
};

static const struct bond_opt_value bond_resend_igmp_tbl[] = {
        { "off",     0,   0},
        { "maxval",  255, BOND_VALFLAG_MAX},
        { "default", 1,   BOND_VALFLAG_DEFAULT},
        { NULL,      -1,  0}
};

static const struct bond_opt_value bond_lp_interval_tbl[] = {
        { "minval",  1,       BOND_VALFLAG_MIN | BOND_VALFLAG_DEFAULT},
        { "maxval",  INT_MAX, BOND_VALFLAG_MAX},
        { NULL,      -1,      0},
};

static const struct bond_opt_value bond_tlb_dynamic_lb_tbl[] = {
        { "off", 0,  0},
        { "on",  1,  BOND_VALFLAG_DEFAULT},
        { NULL,  -1, 0}
};

static const struct bond_option bond_opts[] = {
        [BOND_OPT_MODE] = {
                .id = BOND_OPT_MODE,
                .name = "mode",
                .desc = "bond device mode",
                .flags = BOND_OPTFLAG_NOSLAVES | BOND_OPTFLAG_IFDOWN,
                .values = bond_mode_tbl,
                .set = bond_option_mode_set
        },
        [BOND_OPT_PACKETS_PER_SLAVE] = {
                .id = BOND_OPT_PACKETS_PER_SLAVE,
                .name = "packets_per_slave",
                .desc = "Packets to send per slave in RR mode",
                .unsuppmodes = BOND_MODE_ALL_EX(BIT(BOND_MODE_ROUNDROBIN)),
                .values = bond_pps_tbl,
                .set = bond_option_pps_set
        },
        [BOND_OPT_XMIT_HASH] = {
                .id = BOND_OPT_XMIT_HASH,
                .name = "xmit_hash_policy",
                .desc = "balance-xor, 802.3ad, and tlb hashing method",
                .values = bond_xmit_hashtype_tbl,
                .set = bond_option_xmit_hash_policy_set
        },
        [BOND_OPT_ARP_VALIDATE] = {
                .id = BOND_OPT_ARP_VALIDATE,
                .name = "arp_validate",
                .desc = "validate src/dst of ARP probes",
                .unsuppmodes = BIT(BOND_MODE_8023AD) | BIT(BOND_MODE_TLB) |
                               BIT(BOND_MODE_ALB),
                .values = bond_arp_validate_tbl,
                .set = bond_option_arp_validate_set
        },
        [BOND_OPT_ARP_ALL_TARGETS] = {
                .id = BOND_OPT_ARP_ALL_TARGETS,
                .name = "arp_all_targets",
                .desc = "fail on any/all arp targets timeout",
                .values = bond_arp_all_targets_tbl,
                .set = bond_option_arp_all_targets_set
        },
        [BOND_OPT_FAIL_OVER_MAC] = {
                .id = BOND_OPT_FAIL_OVER_MAC,
                .name = "fail_over_mac",
                .desc = "For active-backup, do not set all slaves to the same MAC",
                .flags = BOND_OPTFLAG_NOSLAVES,
                .values = bond_fail_over_mac_tbl,
                .set = bond_option_fail_over_mac_set
        },
        [BOND_OPT_ARP_INTERVAL] = {
                .id = BOND_OPT_ARP_INTERVAL,
                .name = "arp_interval",
                .desc = "arp interval in milliseconds",
                .unsuppmodes = BIT(BOND_MODE_8023AD) | BIT(BOND_MODE_TLB) |
                               BIT(BOND_MODE_ALB),
                .values = bond_intmax_tbl,
                .set = bond_option_arp_interval_set
        },
        [BOND_OPT_ARP_TARGETS] = {
                .id = BOND_OPT_ARP_TARGETS,
                .name = "arp_ip_target",
                .desc = "arp targets in n.n.n.n form",
                .flags = BOND_OPTFLAG_RAWVAL,
                .set = bond_option_arp_ip_targets_set
        },
        [BOND_OPT_DOWNDELAY] = {
                .id = BOND_OPT_DOWNDELAY,
                .name = "downdelay",
                .desc = "Delay before considering link down, in milliseconds",
                .values = bond_intmax_tbl,
                .set = bond_option_downdelay_set
        },
        [BOND_OPT_UPDELAY] = {
                .id = BOND_OPT_UPDELAY,
                .name = "updelay",
                .desc = "Delay before considering link up, in milliseconds",
                .values = bond_intmax_tbl,
                .set = bond_option_updelay_set
        },
        [BOND_OPT_LACP_RATE] = {
                .id = BOND_OPT_LACP_RATE,
                .name = "lacp_rate",
                .desc = "LACPDU tx rate to request from 802.3ad partner",
                .flags = BOND_OPTFLAG_IFDOWN,
                .unsuppmodes = BOND_MODE_ALL_EX(BIT(BOND_MODE_8023AD)),
                .values = bond_lacp_rate_tbl,
                .set = bond_option_lacp_rate_set
        },
        [BOND_OPT_MINLINKS] = {
                .id = BOND_OPT_MINLINKS,
                .name = "min_links",
                .desc = "Minimum number of available links before turning on carrier",
                .values = bond_intmax_tbl,
                .set = bond_option_min_links_set
        },
        [BOND_OPT_AD_SELECT] = {
                .id = BOND_OPT_AD_SELECT,
                .name = "ad_select",
                .desc = "803.ad aggregation selection logic",
                .flags = BOND_OPTFLAG_IFDOWN,
                .values = bond_ad_select_tbl,
                .set = bond_option_ad_select_set
        },
        [BOND_OPT_NUM_PEER_NOTIF] = {
                .id = BOND_OPT_NUM_PEER_NOTIF,
                .name = "num_unsol_na",
                .desc = "Number of peer notifications to send on failover event",
                .values = bond_num_peer_notif_tbl,
                .set = bond_option_num_peer_notif_set
        },
        [BOND_OPT_MIIMON] = {
                .id = BOND_OPT_MIIMON,
                .name = "miimon",
                .desc = "Link check interval in milliseconds",
                .values = bond_intmax_tbl,
                .set = bond_option_miimon_set
        },
        [BOND_OPT_PRIMARY] = {
                .id = BOND_OPT_PRIMARY,
                .name = "primary",
                .desc = "Primary network device to use",
                .flags = BOND_OPTFLAG_RAWVAL,
                .unsuppmodes = BOND_MODE_ALL_EX(BIT(BOND_MODE_ACTIVEBACKUP) |
                                                BIT(BOND_MODE_TLB) |
                                                BIT(BOND_MODE_ALB)),
                .set = bond_option_primary_set
        },
        [BOND_OPT_PRIMARY_RESELECT] = {
                .id = BOND_OPT_PRIMARY_RESELECT,
                .name = "primary_reselect",
                .desc = "Reselect primary slave once it comes up",
                .values = bond_primary_reselect_tbl,
                .set = bond_option_primary_reselect_set
        },
        [BOND_OPT_USE_CARRIER] = {
                .id = BOND_OPT_USE_CARRIER,
                .name = "use_carrier",
                .desc = "Use netif_carrier_ok (vs MII ioctls) in miimon",
                .values = bond_use_carrier_tbl,
                .set = bond_option_use_carrier_set
        },
        [BOND_OPT_ACTIVE_SLAVE] = {
                .id = BOND_OPT_ACTIVE_SLAVE,
                .name = "active_slave",
                .desc = "Currently active slave",
                .flags = BOND_OPTFLAG_RAWVAL,
                .unsuppmodes = BOND_MODE_ALL_EX(BIT(BOND_MODE_ACTIVEBACKUP) |
                                                BIT(BOND_MODE_TLB) |
                                                BIT(BOND_MODE_ALB)),
                .set = bond_option_active_slave_set
        },
        [BOND_OPT_QUEUE_ID] = {
                .id = BOND_OPT_QUEUE_ID,
                .name = "queue_id",
                .desc = "Set queue id of a slave",
                .flags = BOND_OPTFLAG_RAWVAL,
                .set = bond_option_queue_id_set
        },
        [BOND_OPT_ALL_SLAVES_ACTIVE] = {
                .id = BOND_OPT_ALL_SLAVES_ACTIVE,
                .name = "all_slaves_active",
                .desc = "Keep all frames received on an interface by setting active flag for all slaves",
                .values = bond_all_slaves_active_tbl,
                .set = bond_option_all_slaves_active_set
        },
        [BOND_OPT_RESEND_IGMP] = {
                .id = BOND_OPT_RESEND_IGMP,
                .name = "resend_igmp",
                .desc = "Number of IGMP membership reports to send on link failure",
                .values = bond_resend_igmp_tbl,
                .set = bond_option_resend_igmp_set
        },
        [BOND_OPT_LP_INTERVAL] = {
                .id = BOND_OPT_LP_INTERVAL,
                .name = "lp_interval",
                .desc = "The number of seconds between instances where the bonding driver sends learning packets to each slave's peer switch",
                .values = bond_lp_interval_tbl,
                .set = bond_option_lp_interval_set
        },
        [BOND_OPT_SLAVES] = {
                .id = BOND_OPT_SLAVES,
                .name = "slaves",
                .desc = "Slave membership management",
                .flags = BOND_OPTFLAG_RAWVAL,
                .set = bond_option_slaves_set
        },
        [BOND_OPT_TLB_DYNAMIC_LB] = {
                .id = BOND_OPT_TLB_DYNAMIC_LB,
                .name = "tlb_dynamic_lb",
                .desc = "Enable dynamic flow shuffling",
                .unsuppmodes = BOND_MODE_ALL_EX(BIT(BOND_MODE_TLB)),
                .values = bond_tlb_dynamic_lb_tbl,
                .flags = BOND_OPTFLAG_IFDOWN,
                .set = bond_option_tlb_dynamic_lb_set,
        },
        { }
};

/* Searches for an option by name */
const struct bond_option *bond_opt_get_by_name(const char *name)
{
        const struct bond_option *opt;
        int option;

        for (option = 0; option < BOND_OPT_LAST; option++) {
                opt = bond_opt_get(option);
                if (opt && !strcmp(opt->name, name))
                        return opt;
        }

        return NULL;
}

/* Searches for a value in opt's values[] table */
const struct bond_opt_value *bond_opt_get_val(unsigned int option, u64 val)
{
        const struct bond_option *opt;
        int i;

        opt = bond_opt_get(option);
        if (WARN_ON(!opt))
                return NULL;
        for (i = 0; opt->values && opt->values[i].string; i++)
                if (opt->values[i].value == val)
                        return &opt->values[i];

        return NULL;
}

/* Searches for a value in opt's values[] table which matches the flagmask */
static const struct bond_opt_value *bond_opt_get_flags(const struct bond_option *opt,
                                                 u32 flagmask)
{
        int i;

        for (i = 0; opt->values && opt->values[i].string; i++)
                if (opt->values[i].flags & flagmask)
                        return &opt->values[i];

        return NULL;
}

/* If maxval is missing then there's no range to check. In case minval is
 * missing then it's considered to be 0.
 */
static bool bond_opt_check_range(const struct bond_option *opt, u64 val)
{
        const struct bond_opt_value *minval, *maxval;

        minval = bond_opt_get_flags(opt, BOND_VALFLAG_MIN);
        maxval = bond_opt_get_flags(opt, BOND_VALFLAG_MAX);
        if (!maxval || (minval && val < minval->value) || val > maxval->value)
                return false;

        return true;
}

/**
 * bond_opt_parse - parse option value
 * @opt: the option to parse against
 * @val: value to parse
 *
 * This function tries to extract the value from @val and check if it's
 * a possible match for the option and returns NULL if a match isn't found,
 * or the struct_opt_value that matched. It also strips the new line from
 * @val->string if it's present.
 */
const struct bond_opt_value *bond_opt_parse(const struct bond_option *opt,
                                            struct bond_opt_value *val)
{
        char *p, valstr[BOND_OPT_MAX_NAMELEN + 1] = { 0, };
        const struct bond_opt_value *tbl;
        const struct bond_opt_value *ret = NULL;
        bool checkval;
        int i, rv;

        /* No parsing if the option wants a raw val */
        if (opt->flags & BOND_OPTFLAG_RAWVAL)
                return val;

        tbl = opt->values;
        if (!tbl)
                goto out;

        /* ULLONG_MAX is used to bypass string processing */
        checkval = val->value != ULLONG_MAX;
        if (!checkval) {
                if (!val->string)
                        goto out;
                p = strchr(val->string, '\n');
                if (p)
                        *p = '\0';
                for (p = val->string; *p; p++)
                        if (!(isdigit(*p) || isspace(*p)))
                                break;
                /* The following code extracts the string to match or the value
                 * and sets checkval appropriately
                 */
                if (*p) {
                        rv = sscanf(val->string, "%32s", valstr);
                } else {
                        rv = sscanf(val->string, "%llu", &val->value);
                        checkval = true;
                }
                if (!rv)
                        goto out;
        }

        for (i = 0; tbl[i].string; i++) {
                /* Check for exact match */
                if (checkval) {
                        if (val->value == tbl[i].value)
                                ret = &tbl[i];
                } else {
                        if (!strcmp(valstr, "default") &&
                            (tbl[i].flags & BOND_VALFLAG_DEFAULT))
                                ret = &tbl[i];

                        if (!strcmp(valstr, tbl[i].string))
                                ret = &tbl[i];
                }
                /* Found an exact match */
                if (ret)
                        goto out;
        }
        /* Possible range match */
        if (checkval && bond_opt_check_range(opt, val->value))
                ret = val;
out:
        return ret;
}

/* Check opt's dependencies against bond mode and currently set options */
static int bond_opt_check_deps(struct bonding *bond,
                               const struct bond_option *opt)
{
        struct bond_params *params = &bond->params;

        if (test_bit(params->mode, &opt->unsuppmodes))
                return -EACCES;
        if ((opt->flags & BOND_OPTFLAG_NOSLAVES) && bond_has_slaves(bond))
                return -ENOTEMPTY;
        if ((opt->flags & BOND_OPTFLAG_IFDOWN) && (bond->dev->flags & IFF_UP))
                return -EBUSY;

        return 0;
}

static void bond_opt_dep_print(struct bonding *bond,
                               const struct bond_option *opt)
{
        const struct bond_opt_value *modeval;
        struct bond_params *params;

        params = &bond->params;
        modeval = bond_opt_get_val(BOND_OPT_MODE, params->mode);
        if (test_bit(params->mode, &opt->unsuppmodes))
                netdev_err(bond->dev, "option %s: mode dependency failed, not supported in mode %s(%llu)\n",
                           opt->name, modeval->string, modeval->value);
}

static void bond_opt_error_interpret(struct bonding *bond,
                                     const struct bond_option *opt,
                                     int error, const struct bond_opt_value *val)
{
        const struct bond_opt_value *minval, *maxval;
        char *p;

        switch (error) {
        case -EINVAL:
                if (val) {
                        if (val->string) {
                                /* sometimes RAWVAL opts may have new lines */
                                p = strchr(val->string, '\n');
                                if (p)
                                        *p = '\0';
                                netdev_err(bond->dev, "option %s: invalid value (%s)\n",
                                           opt->name, val->string);
                        } else {
                                netdev_err(bond->dev, "option %s: invalid value (%llu)\n",
                                           opt->name, val->value);
                        }
                }
                minval = bond_opt_get_flags(opt, BOND_VALFLAG_MIN);
                maxval = bond_opt_get_flags(opt, BOND_VALFLAG_MAX);
                if (!maxval)
                        break;
                netdev_err(bond->dev, "option %s: allowed values %llu - %llu\n",
                           opt->name, minval ? minval->value : 0, maxval->value);
                break;
        case -EACCES:
                bond_opt_dep_print(bond, opt);
                break;
        case -ENOTEMPTY:
                netdev_err(bond->dev, "option %s: unable to set because the bond device has slaves\n",
                           opt->name);
                break;
        case -EBUSY:
                netdev_err(bond->dev, "option %s: unable to set because the bond device is up\n",
                           opt->name);
                break;
        default:
                break;
        }
}

/**
 * __bond_opt_set - set a bonding option
 * @bond: target bond device
 * @option: option to set
 * @val: value to set it to
 *
 * This function is used to change the bond's option value, it can be
 * used for both enabling/changing an option and for disabling it. RTNL lock
 * must be obtained before calling this function.
 */
int __bond_opt_set(struct bonding *bond,
                   unsigned int option, struct bond_opt_value *val)
{
        const struct bond_opt_value *retval = NULL;
        const struct bond_option *opt;
        int ret = -ENOENT;

        ASSERT_RTNL();

        opt = bond_opt_get(option);
        if (WARN_ON(!val) || WARN_ON(!opt))
                goto out;
        ret = bond_opt_check_deps(bond, opt);
        if (ret)
                goto out;
        retval = bond_opt_parse(opt, val);
        if (!retval) {
                ret = -EINVAL;
                goto out;
        }
        ret = opt->set(bond, retval);
out:
        if (ret)
                bond_opt_error_interpret(bond, opt, ret, val);
        else
                call_netdevice_notifiers(NETDEV_CHANGEINFODATA, bond->dev);

        return ret;
}

/**
 * bond_opt_tryset_rtnl - try to acquire rtnl and call __bond_opt_set
 * @bond: target bond device
 * @option: option to set
 * @buf: value to set it to
 *
 * This function tries to acquire RTNL without blocking and if successful
 * calls __bond_opt_set. It is mainly used for sysfs option manipulation.
 */
int bond_opt_tryset_rtnl(struct bonding *bond, unsigned int option, char *buf)
{
        struct bond_opt_value optval;
        int ret;

        if (!rtnl_trylock())
                return restart_syscall();
        bond_opt_initstr(&optval, buf);
        ret = __bond_opt_set(bond, option, &optval);
        rtnl_unlock();

        return ret;
}

/**
 * bond_opt_get - get a pointer to an option
 * @option: option for which to return a pointer
 *
 * This function checks if option is valid and if so returns a pointer
 * to its entry in the bond_opts[] option array.
 */
const struct bond_option *bond_opt_get(unsigned int option)
{
        if (!BOND_OPT_VALID(option))
                return NULL;

        return &bond_opts[option];
}

static int bond_option_mode_set(struct bonding *bond,
                                const struct bond_opt_value *newval)
{
        if (!bond_mode_uses_arp(newval->value) && bond->params.arp_interval) {
                netdev_info(bond->dev, "%s mode is incompatible with arp monitoring, start mii monitoring\n",
                            newval->string);
                /* disable arp monitoring */
                bond->params.arp_interval = 0;
                /* set miimon to default value */
                bond->params.miimon = BOND_DEFAULT_MIIMON;
                netdev_info(bond->dev, "Setting MII monitoring interval to %d\n",
                            bond->params.miimon);
        }

        /* don't cache arp_validate between modes */
        bond->params.arp_validate = BOND_ARP_VALIDATE_NONE;
        bond->params.mode = newval->value;

        return 0;
}

static struct net_device *__bond_option_active_slave_get(struct bonding *bond,
                                                         struct slave *slave)
{
        return bond_uses_primary(bond) && slave ? slave->dev : NULL;
}

struct net_device *bond_option_active_slave_get_rcu(struct bonding *bond)
{
        struct slave *slave = rcu_dereference(bond->curr_active_slave);

        return __bond_option_active_slave_get(bond, slave);
}

static int bond_option_active_slave_set(struct bonding *bond,
                                        const struct bond_opt_value *newval)
{
        char ifname[IFNAMSIZ] = { 0, };
        struct net_device *slave_dev;
        int ret = 0;

        sscanf(newval->string, "%15s", ifname); /* IFNAMSIZ */
        if (!strlen(ifname) || newval->string[0] == '\n') {
                slave_dev = NULL;
        } else {
                slave_dev = __dev_get_by_name(dev_net(bond->dev), ifname);
                if (!slave_dev)
                        return -ENODEV;
        }

        if (slave_dev) {
                if (!netif_is_bond_slave(slave_dev)) {
                        netdev_err(bond->dev, "Device %s is not bonding slave\n",
                                   slave_dev->name);
                        return -EINVAL;
                }

                if (bond->dev != netdev_master_upper_dev_get(slave_dev)) {
                        netdev_err(bond->dev, "Device %s is not our slave\n",
                                   slave_dev->name);
                        return -EINVAL;
                }
        }

        block_netpoll_tx();
        write_lock_bh(&bond->curr_slave_lock);

        /* check to see if we are clearing active */
        if (!slave_dev) {
                netdev_info(bond->dev, "Clearing current active slave\n");
                RCU_INIT_POINTER(bond->curr_active_slave, NULL);
                bond_select_active_slave(bond);
        } else {
                struct slave *old_active = bond_deref_active_protected(bond);
                struct slave *new_active = bond_slave_get_rtnl(slave_dev);

                BUG_ON(!new_active);

                if (new_active == old_active) {
                        /* do nothing */
                        netdev_info(bond->dev, "%s is already the current active slave\n",
                                    new_active->dev->name);
                } else {
                        if (old_active && (new_active->link == BOND_LINK_UP) &&
                            bond_slave_is_up(new_active)) {
                                netdev_info(bond->dev, "Setting %s as active slave\n",
                                            new_active->dev->name);
                                bond_change_active_slave(bond, new_active);
                        } else {
                                netdev_err(bond->dev, "Could not set %s as active slave; either %s is down or the link is down\n",
                                           new_active->dev->name,
                                           new_active->dev->name);
                                ret = -EINVAL;
                        }
                }
        }

        write_unlock_bh(&bond->curr_slave_lock);
        unblock_netpoll_tx();

        return ret;
}

/* There are two tricky bits here.  First, if MII monitoring is activated, then
 * we must disable ARP monitoring.  Second, if the timer isn't running, we must
 * start it.
 */
static int bond_option_miimon_set(struct bonding *bond,
                                  const struct bond_opt_value *newval)
{
        netdev_info(bond->dev, "Setting MII monitoring interval to %llu\n",
                    newval->value);
        bond->params.miimon = newval->value;
        if (bond->params.updelay)
                netdev_info(bond->dev, "Note: Updating updelay (to %d) since it is a multiple of the miimon value\n",
                        bond->params.updelay * bond->params.miimon);
        if (bond->params.downdelay)
                netdev_info(bond->dev, "Note: Updating downdelay (to %d) since it is a multiple of the miimon value\n",
                            bond->params.downdelay * bond->params.miimon);
        if (newval->value && bond->params.arp_interval) {
                netdev_info(bond->dev, "MII monitoring cannot be used with ARP monitoring - disabling ARP monitoring...\n");
                bond->params.arp_interval = 0;
                if (bond->params.arp_validate)
                        bond->params.arp_validate = BOND_ARP_VALIDATE_NONE;
        }
        if (bond->dev->flags & IFF_UP) {
                /* If the interface is up, we may need to fire off
                 * the MII timer. If the interface is down, the
                 * timer will get fired off when the open function
                 * is called.
                 */
                if (!newval->value) {
                        cancel_delayed_work_sync(&bond->mii_work);
                } else {
                        cancel_delayed_work_sync(&bond->arp_work);
                        queue_delayed_work(bond->wq, &bond->mii_work, 0);
                }
        }

        return 0;
}

/* Set up and down delays. These must be multiples of the
 * MII monitoring value, and are stored internally as the multiplier.
 * Thus, we must translate to MS for the real world.
 */
static int bond_option_updelay_set(struct bonding *bond,
                                   const struct bond_opt_value *newval)
{
        int value = newval->value;

        if (!bond->params.miimon) {
                netdev_err(bond->dev, "Unable to set up delay as MII monitoring is disabled\n");
                return -EPERM;
        }
        if ((value % bond->params.miimon) != 0) {
                netdev_warn(bond->dev, "up delay (%d) is not a multiple of miimon (%d), updelay rounded to %d ms\n",
                            value, bond->params.miimon,
                            (value / bond->params.miimon) *
                            bond->params.miimon);
        }
        bond->params.updelay = value / bond->params.miimon;
        netdev_info(bond->dev, "Setting up delay to %d\n",
                    bond->params.updelay * bond->params.miimon);

        return 0;
}

static int bond_option_downdelay_set(struct bonding *bond,
                                     const struct bond_opt_value *newval)
{
        int value = newval->value;

        if (!bond->params.miimon) {
                netdev_err(bond->dev, "Unable to set down delay as MII monitoring is disabled\n");
                return -EPERM;
        }
        if ((value % bond->params.miimon) != 0) {
                netdev_warn(bond->dev, "down delay (%d) is not a multiple of miimon (%d), delay rounded to %d ms\n",
                            value, bond->params.miimon,
                            (value / bond->params.miimon) *
                            bond->params.miimon);
        }
        bond->params.downdelay = value / bond->params.miimon;
        netdev_info(bond->dev, "Setting down delay to %d\n",
                    bond->params.downdelay * bond->params.miimon);

        return 0;
}

static int bond_option_use_carrier_set(struct bonding *bond,
                                       const struct bond_opt_value *newval)
{
        netdev_info(bond->dev, "Setting use_carrier to %llu\n",
                    newval->value);
        bond->params.use_carrier = newval->value;

        return 0;
}

/* There are two tricky bits here.  First, if ARP monitoring is activated, then
 * we must disable MII monitoring.  Second, if the ARP timer isn't running,
 * we must start it.
 */
static int bond_option_arp_interval_set(struct bonding *bond,
                                        const struct bond_opt_value *newval)
{
        netdev_info(bond->dev, "Setting ARP monitoring interval to %llu\n",
                    newval->value);
        bond->params.arp_interval = newval->value;
        if (newval->value) {
                if (bond->params.miimon) {
                        netdev_info(bond->dev, "ARP monitoring cannot be used with MII monitoring. Disabling MII monitoring\n");
                        bond->params.miimon = 0;
                }
                if (!bond->params.arp_targets[0])
                        netdev_info(bond->dev, "ARP monitoring has been set up, but no ARP targets have been specified\n");
        }
        if (bond->dev->flags & IFF_UP) {
                /* If the interface is up, we may need to fire off
                 * the ARP timer.  If the interface is down, the
                 * timer will get fired off when the open function
                 * is called.
                 */
                if (!newval->value) {
                        if (bond->params.arp_validate)
                                bond->recv_probe = NULL;
                        cancel_delayed_work_sync(&bond->arp_work);
                } else {
                        /* arp_validate can be set only in active-backup mode */
                        bond->recv_probe = bond_arp_rcv;
                        cancel_delayed_work_sync(&bond->mii_work);
                        queue_delayed_work(bond->wq, &bond->arp_work, 0);
                }
        }

        return 0;
}

static void _bond_options_arp_ip_target_set(struct bonding *bond, int slot,
                                            __be32 target,
                                            unsigned long last_rx)
{
        __be32 *targets = bond->params.arp_targets;
        struct list_head *iter;
        struct slave *slave;

        if (slot >= 0 && slot < BOND_MAX_ARP_TARGETS) {
                bond_for_each_slave(bond, slave, iter)
                        slave->target_last_arp_rx[slot] = last_rx;
                targets[slot] = target;
        }
}

static int _bond_option_arp_ip_target_add(struct bonding *bond, __be32 target)
{
        __be32 *targets = bond->params.arp_targets;
        int ind;

        if (!bond_is_ip_target_ok(target)) {
                netdev_err(bond->dev, "invalid ARP target %pI4 specified for addition\n",
                           &target);
                return -EINVAL;
        }

        if (bond_get_targets_ip(targets, target) != -1) { /* dup */
                netdev_err(bond->dev, "ARP target %pI4 is already present\n",
                           &target);
                return -EINVAL;
        }

        ind = bond_get_targets_ip(targets, 0); /* first free slot */
        if (ind == -1) {
                netdev_err(bond->dev, "ARP target table is full!\n");
                return -EINVAL;
        }

        netdev_info(bond->dev, "Adding ARP target %pI4\n", &target);

        _bond_options_arp_ip_target_set(bond, ind, target, jiffies);

        return 0;
}

static int bond_option_arp_ip_target_add(struct bonding *bond, __be32 target)
{
        int ret;

        /* not to race with bond_arp_rcv */
        write_lock_bh(&bond->lock);
        ret = _bond_option_arp_ip_target_add(bond, target);
        write_unlock_bh(&bond->lock);

        return ret;
}

static int bond_option_arp_ip_target_rem(struct bonding *bond, __be32 target)
{
        __be32 *targets = bond->params.arp_targets;
        struct list_head *iter;
        struct slave *slave;
        unsigned long *targets_rx;
        int ind, i;

        if (!bond_is_ip_target_ok(target)) {
                netdev_err(bond->dev, "invalid ARP target %pI4 specified for removal\n",
                           &target);
                return -EINVAL;
        }

        ind = bond_get_targets_ip(targets, target);
        if (ind == -1) {
                netdev_err(bond->dev, "unable to remove nonexistent ARP target %pI4\n",
                           &target);
                return -EINVAL;
        }

        if (ind == 0 && !targets[1] && bond->params.arp_interval)
                netdev_warn(bond->dev, "Removing last arp target with arp_interval on\n");

        netdev_info(bond->dev, "Removing ARP target %pI4\n", &target);

        /* not to race with bond_arp_rcv */
        write_lock_bh(&bond->lock);

        bond_for_each_slave(bond, slave, iter) {
                targets_rx = slave->target_last_arp_rx;
                for (i = ind; (i < BOND_MAX_ARP_TARGETS-1) && targets[i+1]; i++)
                        targets_rx[i] = targets_rx[i+1];
                targets_rx[i] = 0;
        }
        for (i = ind; (i < BOND_MAX_ARP_TARGETS-1) && targets[i+1]; i++)
                targets[i] = targets[i+1];
        targets[i] = 0;

        write_unlock_bh(&bond->lock);

        return 0;
}

void bond_option_arp_ip_targets_clear(struct bonding *bond)
{
        int i;

        /* not to race with bond_arp_rcv */
        write_lock_bh(&bond->lock);
        for (i = 0; i < BOND_MAX_ARP_TARGETS; i++)
                _bond_options_arp_ip_target_set(bond, i, 0, 0);
        write_unlock_bh(&bond->lock);
}

static int bond_option_arp_ip_targets_set(struct bonding *bond,
                                          const struct bond_opt_value *newval)
{
        int ret = -EPERM;
        __be32 target;

        if (newval->string) {
                if (!in4_pton(newval->string+1, -1, (u8 *)&target, -1, NULL)) {
                        netdev_err(bond->dev, "invalid ARP target %pI4 specified\n",
                                   &target);
                        return ret;
                }
                if (newval->string[0] == '+')
                        ret = bond_option_arp_ip_target_add(bond, target);
                else if (newval->string[0] == '-')
                        ret = bond_option_arp_ip_target_rem(bond, target);
                else
                        netdev_err(bond->dev, "no command found in arp_ip_targets file - use +<addr> or -<addr>\n");
        } else {
                target = newval->value;
                ret = bond_option_arp_ip_target_add(bond, target);
        }

        return ret;
}

static int bond_option_arp_validate_set(struct bonding *bond,
                                        const struct bond_opt_value *newval)
{
        netdev_info(bond->dev, "Setting arp_validate to %s (%llu)\n",
                    newval->string, newval->value);

        if (bond->dev->flags & IFF_UP) {
                if (!newval->value)
                        bond->recv_probe = NULL;
                else if (bond->params.arp_interval)
                        bond->recv_probe = bond_arp_rcv;
        }
        bond->params.arp_validate = newval->value;

        return 0;
}

static int bond_option_arp_all_targets_set(struct bonding *bond,
                                           const struct bond_opt_value *newval)
{
        netdev_info(bond->dev, "Setting arp_all_targets to %s (%llu)\n",
                    newval->string, newval->value);
        bond->params.arp_all_targets = newval->value;

        return 0;
}

static int bond_option_primary_set(struct bonding *bond,
                                   const struct bond_opt_value *newval)
{
        char *p, *primary = newval->string;
        struct list_head *iter;
        struct slave *slave;

        block_netpoll_tx();
        read_lock(&bond->lock);
        write_lock_bh(&bond->curr_slave_lock);

        p = strchr(primary, '\n');
        if (p)
                *p = '\0';
        /* check to see if we are clearing primary */
        if (!strlen(primary)) {
                netdev_info(bond->dev, "Setting primary slave to None\n");
                RCU_INIT_POINTER(bond->primary_slave, NULL);
                memset(bond->params.primary, 0, sizeof(bond->params.primary));
                bond_select_active_slave(bond);
                goto out;
        }

        bond_for_each_slave(bond, slave, iter) {
                if (strncmp(slave->dev->name, primary, IFNAMSIZ) == 0) {
                        netdev_info(bond->dev, "Setting %s as primary slave\n",
                                    slave->dev->name);
                        rcu_assign_pointer(bond->primary_slave, slave);
                        strcpy(bond->params.primary, slave->dev->name);
                        bond_select_active_slave(bond);
                        goto out;
                }
        }

        if (rtnl_dereference(bond->primary_slave)) {
                netdev_info(bond->dev, "Setting primary slave to None\n");
                RCU_INIT_POINTER(bond->primary_slave, NULL);
                bond_select_active_slave(bond);
        }
        strncpy(bond->params.primary, primary, IFNAMSIZ);
        bond->params.primary[IFNAMSIZ - 1] = 0;

        netdev_info(bond->dev, "Recording %s as primary, but it has not been enslaved to %s yet\n",
                    primary, bond->dev->name);

out:
        write_unlock_bh(&bond->curr_slave_lock);
        read_unlock(&bond->lock);
        unblock_netpoll_tx();

        return 0;
}

static int bond_option_primary_reselect_set(struct bonding *bond,
                                            const struct bond_opt_value *newval)
{
        netdev_info(bond->dev, "Setting primary_reselect to %s (%llu)\n",
                    newval->string, newval->value);
        bond->params.primary_reselect = newval->value;

        block_netpoll_tx();
        write_lock_bh(&bond->curr_slave_lock);
        bond_select_active_slave(bond);
        write_unlock_bh(&bond->curr_slave_lock);
        unblock_netpoll_tx();

        return 0;
}

static int bond_option_fail_over_mac_set(struct bonding *bond,
                                         const struct bond_opt_value *newval)
{
        netdev_info(bond->dev, "Setting fail_over_mac to %s (%llu)\n",
                    newval->string, newval->value);
        bond->params.fail_over_mac = newval->value;

        return 0;
}

static int bond_option_xmit_hash_policy_set(struct bonding *bond,
                                            const struct bond_opt_value *newval)
{
        netdev_info(bond->dev, "Setting xmit hash policy to %s (%llu)\n",
                    newval->string, newval->value);
        bond->params.xmit_policy = newval->value;

        return 0;
}

static int bond_option_resend_igmp_set(struct bonding *bond,
                                       const struct bond_opt_value *newval)
{
        netdev_info(bond->dev, "Setting resend_igmp to %llu\n",
                    newval->value);
        bond->params.resend_igmp = newval->value;

        return 0;
}

static int bond_option_num_peer_notif_set(struct bonding *bond,
                                   const struct bond_opt_value *newval)
{
        bond->params.num_peer_notif = newval->value;

        return 0;
}

static int bond_option_all_slaves_active_set(struct bonding *bond,
                                             const struct bond_opt_value *newval)
{
        struct list_head *iter;
        struct slave *slave;

        if (newval->value == bond->params.all_slaves_active)
                return 0;
        bond->params.all_slaves_active = newval->value;
        bond_for_each_slave(bond, slave, iter) {
                if (!bond_is_active_slave(slave)) {
                        if (newval->value)
                                slave->inactive = 0;
                        else
                                slave->inactive = 1;
                }
        }

        return 0;
}

static int bond_option_min_links_set(struct bonding *bond,
                                     const struct bond_opt_value *newval)
{
        netdev_info(bond->dev, "Setting min links value to %llu\n",
                    newval->value);
        bond->params.min_links = newval->value;

        return 0;
}

static int bond_option_lp_interval_set(struct bonding *bond,
                                       const struct bond_opt_value *newval)
{
        bond->params.lp_interval = newval->value;

        return 0;
}

static int bond_option_pps_set(struct bonding *bond,
                               const struct bond_opt_value *newval)
{
        bond->params.packets_per_slave = newval->value;
        if (newval->value > 0) {
                bond->params.reciprocal_packets_per_slave =
                        reciprocal_value(newval->value);
        } else {
                /* reciprocal_packets_per_slave is unused if
                 * packets_per_slave is 0 or 1, just initialize it
                 */
                bond->params.reciprocal_packets_per_slave =
                        (struct reciprocal_value) { 0 };
        }

        return 0;
}

static int bond_option_lacp_rate_set(struct bonding *bond,
                                     const struct bond_opt_value *newval)
{
        netdev_info(bond->dev, "Setting LACP rate to %s (%llu)\n",
                    newval->string, newval->value);
        bond->params.lacp_fast = newval->value;
        bond_3ad_update_lacp_rate(bond);

        return 0;
}

static int bond_option_ad_select_set(struct bonding *bond,
                                     const struct bond_opt_value *newval)
{
        netdev_info(bond->dev, "Setting ad_select to %s (%llu)\n",
                    newval->string, newval->value);
        bond->params.ad_select = newval->value;

        return 0;
}

static int bond_option_queue_id_set(struct bonding *bond,
                                    const struct bond_opt_value *newval)
{
        struct slave *slave, *update_slave;
        struct net_device *sdev;
        struct list_head *iter;
        char *delim;
        int ret = 0;
        u16 qid;

        /* delim will point to queue id if successful */
        delim = strchr(newval->string, ':');
        if (!delim)
                goto err_no_cmd;

        /* Terminate string that points to device name and bump it
         * up one, so we can read the queue id there.
         */
        *delim = '\0';
        if (sscanf(++delim, "%hd\n", &qid) != 1)
                goto err_no_cmd;

        /* Check buffer length, valid ifname and queue id */
        if (!dev_valid_name(newval->string) ||
            qid > bond->dev->real_num_tx_queues)
                goto err_no_cmd;

        /* Get the pointer to that interface if it exists */
        sdev = __dev_get_by_name(dev_net(bond->dev), newval->string);
        if (!sdev)
                goto err_no_cmd;

        /* Search for thes slave and check for duplicate qids */
        update_slave = NULL;
        bond_for_each_slave(bond, slave, iter) {
                if (sdev == slave->dev)
                        /* We don't need to check the matching
                         * slave for dups, since we're overwriting it
                         */
                        update_slave = slave;
                else if (qid && qid == slave->queue_id) {
                        goto err_no_cmd;
                }
        }

        if (!update_slave)
                goto err_no_cmd;

        /* Actually set the qids for the slave */
        update_slave->queue_id = qid;

out:
        return ret;

err_no_cmd:
        netdev_info(bond->dev, "invalid input for queue_id set\n");
        ret = -EPERM;
        goto out;

}

static int bond_option_slaves_set(struct bonding *bond,
                                  const struct bond_opt_value *newval)
{
        char command[IFNAMSIZ + 1] = { 0, };
        struct net_device *dev;
        char *ifname;
        int ret;

        sscanf(newval->string, "%16s", command); /* IFNAMSIZ*/
        ifname = command + 1;
        if ((strlen(command) <= 1) ||
            !dev_valid_name(ifname))
                goto err_no_cmd;

        dev = __dev_get_by_name(dev_net(bond->dev), ifname);
        if (!dev) {
                netdev_info(bond->dev, "interface %s does not exist!\n",
                            ifname);
                ret = -ENODEV;
                goto out;
        }

        switch (command[0]) {
        case '+':
                netdev_info(bond->dev, "Adding slave %s\n", dev->name);
                ret = bond_enslave(bond->dev, dev);
                break;

        case '-':
                netdev_info(bond->dev, "Removing slave %s\n", dev->name);
                ret = bond_release(bond->dev, dev);
                break;

        default:
                goto err_no_cmd;
        }

out:
        return ret;

err_no_cmd:
        netdev_err(bond->dev, "no command found in slaves file - use +ifname or -ifname\n");
        ret = -EPERM;
        goto out;
}

static int bond_option_tlb_dynamic_lb_set(struct bonding *bond,
                                          const struct bond_opt_value *newval)
{
        netdev_info(bond->dev, "Setting dynamic-lb to %s (%llu)\n",
                    newval->string, newval->value);
        bond->params.tlb_dynamic_lb = newval->value;

        return 0;
}