ceph/src/spdk/dpdk/drivers/net/tap/tap_tcmsgs.c

   1 /* SPDX-License-Identifier: BSD-3-Clause
   2  * Copyright 2017 6WIND S.A.
   3  * Copyright 2017 Mellanox Technologies, Ltd
   4  */
   5
   6 #include <inttypes.h>
   7 #include <linux/netlink.h>
   8 #include <net/if.h>
   9 #include <string.h>
  10
  11 #include <rte_log.h>
  12 #include <tap_tcmsgs.h>
  13 #include "tap_log.h"
  14
  15 struct qdisc {
  16         uint32_t handle;
  17         uint32_t parent;
  18 };
  19
  20 struct list_args {
  21         int nlsk_fd;
  22         uint16_t ifindex;
  23         void *custom_arg;
  24 };
  25
  26 struct qdisc_custom_arg {
  27         uint32_t handle;
  28         uint32_t parent;
  29         uint8_t exists;
  30 };
  31
  32 /**
  33  * Initialize a netlink message with a TC header.
  34  *
  35  * @param[in, out] msg
  36  *   The netlink message to fill.
  37  * @param[in] ifindex
  38  *   The netdevice ifindex where the rule will be applied.
  39  * @param[in] type
  40  *   The type of TC message to create (RTM_NEWTFILTER, RTM_NEWQDISC, etc.).
  41  * @param[in] flags
  42  *   Overrides the default netlink flags for this msg with those specified.
  43  */
  44 void
  45 tc_init_msg(struct nlmsg *msg, uint16_t ifindex, uint16_t type, uint16_t flags)
  46 {
  47         struct nlmsghdr *n = &msg->nh;
  48
  49         n->nlmsg_len = NLMSG_LENGTH(sizeof(struct tcmsg));
  50         n->nlmsg_type = type;
  51         if (flags)
  52                 n->nlmsg_flags = flags;
  53         else
  54                 n->nlmsg_flags = NLM_F_REQUEST | NLM_F_ACK;
  55         msg->t.tcm_family = AF_UNSPEC;
  56         msg->t.tcm_ifindex = ifindex;
  57 }
  58
  59 /**
  60  * Delete a specific QDISC identified by its iface, and it's handle and parent.
  61  *
  62  * @param[in] nlsk_fd
  63  *   The netlink socket file descriptor used for communication.
  64  * @param[in] ifindex
  65  *   The netdevice ifindex on whom the deletion will happen.
  66  * @param[in] qinfo
  67  *   Additional info to identify the QDISC (handle and parent).
  68  *
  69  * @return
  70  *   0 on success, -1 otherwise with errno set.
  71  */
  72 static int
  73 qdisc_del(int nlsk_fd, uint16_t ifindex, struct qdisc *qinfo)
  74 {
  75         struct nlmsg msg;
  76         int fd = 0;
  77
  78         tc_init_msg(&msg, ifindex, RTM_DELQDISC, 0);
  79         msg.t.tcm_handle = qinfo->handle;
  80         msg.t.tcm_parent = qinfo->parent;
  81         /* if no netlink socket is provided, create one */
  82         if (!nlsk_fd) {
  83                 fd = tap_nl_init(0);
  84                 if (fd < 0) {
  85                         TAP_LOG(ERR,
  86                                 "Could not delete QDISC: null netlink socket");
  87                         return -1;
  88                 }
  89         } else {
  90                 fd = nlsk_fd;
  91         }
  92         if (tap_nl_send(fd, &msg.nh) < 0)
  93                 goto error;
  94         if (tap_nl_recv_ack(fd) < 0)
  95                 goto error;
  96         if (!nlsk_fd)
  97                 return tap_nl_final(fd);
  98         return 0;
  99 error:
 100         if (!nlsk_fd)
 101                 tap_nl_final(fd);
 102         return -1;
 103 }
 104
 105 /**
 106  * Add the multiqueue QDISC with MULTIQ_MAJOR_HANDLE handle.
 107  *
 108  * @param[in] nlsk_fd
 109  *   The netlink socket file descriptor used for communication.
 110  * @param[in] ifindex
 111  *   The netdevice ifindex where to add the multiqueue QDISC.
 112  *
 113  * @return
 114  *   0 on success, -1 otherwise with errno set.
 115  */
 116 int
 117 qdisc_add_multiq(int nlsk_fd, uint16_t ifindex)
 118 {
 119         struct tc_multiq_qopt opt = {0};
 120         struct nlmsg msg;
 121
 122         tc_init_msg(&msg, ifindex, RTM_NEWQDISC,
 123                     NLM_F_REQUEST | NLM_F_ACK | NLM_F_EXCL | NLM_F_CREATE);
 124         msg.t.tcm_handle = TC_H_MAKE(MULTIQ_MAJOR_HANDLE, 0);
 125         msg.t.tcm_parent = TC_H_ROOT;
 126         tap_nlattr_add(&msg.nh, TCA_KIND, sizeof("multiq"), "multiq");
 127         tap_nlattr_add(&msg.nh, TCA_OPTIONS, sizeof(opt), &opt);
 128         if (tap_nl_send(nlsk_fd, &msg.nh) < 0)
 129                 return -1;
 130         if (tap_nl_recv_ack(nlsk_fd) < 0)
 131                 return -1;
 132         return 0;
 133 }
 134
 135 /**
 136  * Add the ingress QDISC with default ffff: handle.
 137  *
 138  * @param[in] nlsk_fd
 139  *   The netlink socket file descriptor used for communication.
 140  * @param[in] ifindex
 141  *   The netdevice ifindex where the QDISC will be added.
 142  *
 143  * @return
 144  *   0 on success, -1 otherwise with errno set.
 145  */
 146 int
 147 qdisc_add_ingress(int nlsk_fd, uint16_t ifindex)
 148 {
 149         struct nlmsg msg;
 150
 151         tc_init_msg(&msg, ifindex, RTM_NEWQDISC,
 152                     NLM_F_REQUEST | NLM_F_ACK | NLM_F_EXCL | NLM_F_CREATE);
 153         msg.t.tcm_handle = TC_H_MAKE(TC_H_INGRESS, 0);
 154         msg.t.tcm_parent = TC_H_INGRESS;
 155         tap_nlattr_add(&msg.nh, TCA_KIND, sizeof("ingress"), "ingress");
 156         if (tap_nl_send(nlsk_fd, &msg.nh) < 0)
 157                 return -1;
 158         if (tap_nl_recv_ack(nlsk_fd) < 0)
 159                 return -1;
 160         return 0;
 161 }
 162
 163 /**
 164  * Callback function to delete a QDISC.
 165  *
 166  * @param[in] nh
 167  *   The netlink message to parse, received from the kernel.
 168  * @param[in] arg
 169  *   Custom arguments for the callback.
 170  *
 171  * @return
 172  *   0 on success, -1 otherwise with errno set.
 173  */
 174 static int
 175 qdisc_del_cb(struct nlmsghdr *nh, void *arg)
 176 {
 177         struct tcmsg *t = NLMSG_DATA(nh);
 178         struct list_args *args = arg;
 179
 180         struct qdisc qinfo = {
 181                 .handle = t->tcm_handle,
 182                 .parent = t->tcm_parent,
 183         };
 184
 185         /* filter out other ifaces' qdiscs */
 186         if (args->ifindex != (unsigned int)t->tcm_ifindex)
 187                 return 0;
 188         /*
 189          * Use another nlsk_fd (0) to avoid tampering with the current list
 190          * iteration.
 191          */
 192         return qdisc_del(0, args->ifindex, &qinfo);
 193 }
 194
 195 /**
 196  * Iterate over all QDISC, and call the callback() function for each.
 197  *
 198  * @param[in] nlsk_fd
 199  *   The netlink socket file descriptor used for communication.
 200  * @param[in] ifindex
 201  *   The netdevice ifindex where to find QDISCs.
 202  * @param[in] callback
 203  *   The function to call for each QDISC.
 204  * @param[in, out] arg
 205  *   The arguments to provide the callback function with.
 206  *
 207  * @return
 208  *   0 on success, -1 otherwise with errno set.
 209  */
 210 static int
 211 qdisc_iterate(int nlsk_fd, uint16_t ifindex,
 212               int (*callback)(struct nlmsghdr *, void *), void *arg)
 213 {
 214         struct nlmsg msg;
 215         struct list_args args = {
 216                 .nlsk_fd = nlsk_fd,
 217                 .ifindex = ifindex,
 218                 .custom_arg = arg,
 219         };
 220
 221         tc_init_msg(&msg, ifindex, RTM_GETQDISC, NLM_F_REQUEST | NLM_F_DUMP);
 222         if (tap_nl_send(nlsk_fd, &msg.nh) < 0)
 223                 return -1;
 224         if (tap_nl_recv(nlsk_fd, callback, &args) < 0)
 225                 return -1;
 226         return 0;
 227 }
 228
 229 /**
 230  * Delete all QDISCs for a given netdevice.
 231  *
 232  * @param[in] nlsk_fd
 233  *   The netlink socket file descriptor used for communication.
 234  * @param[in] ifindex
 235  *   The netdevice ifindex where to find QDISCs.
 236  *
 237  * @return
 238  *   0 on success, -1 otherwise with errno set.
 239  */
 240 int
 241 qdisc_flush(int nlsk_fd, uint16_t ifindex)
 242 {
 243         return qdisc_iterate(nlsk_fd, ifindex, qdisc_del_cb, NULL);
 244 }
 245
 246 /**
 247  * Create the multiqueue QDISC, only if it does not exist already.
 248  *
 249  * @param[in] nlsk_fd
 250  *   The netlink socket file descriptor used for communication.
 251  * @param[in] ifindex
 252  *   The netdevice ifindex where to add the multiqueue QDISC.
 253  *
 254  * @return
 255  *   0 if the qdisc exists or if has been successfully added.
 256  *   Return -1 otherwise.
 257  */
 258 int
 259 qdisc_create_multiq(int nlsk_fd, uint16_t ifindex)
 260 {
 261         int err = 0;
 262
 263         err = qdisc_add_multiq(nlsk_fd, ifindex);
 264         if (err < 0 && errno != -EEXIST) {
 265                 TAP_LOG(ERR, "Could not add multiq qdisc (%d): %s",
 266                         errno, strerror(errno));
 267                 return -1;
 268         }
 269         return 0;
 270 }
 271
 272 /**
 273  * Create the ingress QDISC, only if it does not exist already.
 274  *
 275  * @param[in] nlsk_fd
 276  *   The netlink socket file descriptor used for communication.
 277  * @param[in] ifindex
 278  *   The netdevice ifindex where to add the ingress QDISC.
 279  *
 280  * @return
 281  *   0 if the qdisc exists or if has been successfully added.
 282  *   Return -1 otherwise.
 283  */
 284 int
 285 qdisc_create_ingress(int nlsk_fd, uint16_t ifindex)
 286 {
 287         int err = 0;
 288
 289         err = qdisc_add_ingress(nlsk_fd, ifindex);
 290         if (err < 0 && errno != -EEXIST) {
 291                 TAP_LOG(ERR, "Could not add ingress qdisc (%d): %s",
 292                         errno, strerror(errno));
 293                 return -1;
 294         }
 295         return 0;
 296 }