1 // SPDX-License-Identifier: GPL-2.0 2 3 #include <linux/mutex.h> 4 #include <linux/netdevice.h> 5 #include <linux/xarray.h> 6 #include <net/net_debug.h> 7 #include <net/page_pool/types.h> 8 #include <net/page_pool/helpers.h> 9 #include <net/sock.h> 10 11 #include "page_pool_priv.h" 12 #include "netdev-genl-gen.h" 13 14 static DEFINE_XARRAY_FLAGS(page_pools, XA_FLAGS_ALLOC1); 15 /* Protects: page_pools, netdevice->page_pools, pool->slow.netdev, pool->user. 16 * Ordering: inside rtnl_lock 17 */ 18 static DEFINE_MUTEX(page_pools_lock); 19 20 /* Page pools are only reachable from user space (via netlink) if they are 21 * linked to a netdev at creation time. Following page pool "visibility" 22 * states are possible: 23 * - normal 24 * - user.list: linked to real netdev, netdev: real netdev 25 * - orphaned - real netdev has disappeared 26 * - user.list: linked to lo, netdev: lo 27 * - invisible - either (a) created without netdev linking, (b) unlisted due 28 * to error, or (c) the entire namespace which owned this pool disappeared 29 * - user.list: unhashed, netdev: unknown 30 */ 31 32 typedef int (*pp_nl_fill_cb)(struct sk_buff *rsp, const struct page_pool *pool, 33 const struct genl_info *info); 34 35 static int 36 netdev_nl_page_pool_get_do(struct genl_info *info, u32 id, pp_nl_fill_cb fill) 37 { 38 struct page_pool *pool; 39 struct sk_buff *rsp; 40 int err; 41 42 mutex_lock(&page_pools_lock); 43 pool = xa_load(&page_pools, id); 44 if (!pool || hlist_unhashed(&pool->user.list) || 45 !net_eq(dev_net(pool->slow.netdev), genl_info_net(info))) { 46 err = -ENOENT; 47 goto err_unlock; 48 } 49 50 rsp = genlmsg_new(GENLMSG_DEFAULT_SIZE, GFP_KERNEL); 51 if (!rsp) { 52 err = -ENOMEM; 53 goto err_unlock; 54 } 55 56 err = fill(rsp, pool, info); 57 if (err) 58 goto err_free_msg; 59 60 mutex_unlock(&page_pools_lock); 61 62 return genlmsg_reply(rsp, info); 63 64 err_free_msg: 65 nlmsg_free(rsp); 66 err_unlock: 67 mutex_unlock(&page_pools_lock); 68 return err; 69 } 70 71 struct page_pool_dump_cb { 72 unsigned long ifindex; 73 u32 pp_id; 74 }; 75 76 static int 77 netdev_nl_page_pool_get_dump(struct sk_buff *skb, struct netlink_callback *cb, 78 pp_nl_fill_cb fill) 79 { 80 struct page_pool_dump_cb *state = (void *)cb->ctx; 81 const struct genl_info *info = genl_info_dump(cb); 82 struct net *net = sock_net(skb->sk); 83 struct net_device *netdev; 84 struct page_pool *pool; 85 int err = 0; 86 87 rtnl_lock(); 88 mutex_lock(&page_pools_lock); 89 for_each_netdev_dump(net, netdev, state->ifindex) { 90 hlist_for_each_entry(pool, &netdev->page_pools, user.list) { 91 if (state->pp_id && state->pp_id < pool->user.id) 92 continue; 93 94 state->pp_id = pool->user.id; 95 err = fill(skb, pool, info); 96 if (err) 97 break; 98 } 99 100 state->pp_id = 0; 101 } 102 mutex_unlock(&page_pools_lock); 103 rtnl_unlock(); 104 105 if (skb->len && err == -EMSGSIZE) 106 return skb->len; 107 return err; 108 } 109 110 static int 111 page_pool_nl_stats_fill(struct sk_buff *rsp, const struct page_pool *pool, 112 const struct genl_info *info) 113 { 114 #ifdef CONFIG_PAGE_POOL_STATS 115 struct page_pool_stats stats = {}; 116 struct nlattr *nest; 117 void *hdr; 118 119 if (!page_pool_get_stats(pool, &stats)) 120 return 0; 121 122 hdr = genlmsg_iput(rsp, info); 123 if (!hdr) 124 return -EMSGSIZE; 125 126 nest = nla_nest_start(rsp, NETDEV_A_PAGE_POOL_STATS_INFO); 127 128 if (nla_put_uint(rsp, NETDEV_A_PAGE_POOL_ID, pool->user.id) || 129 (pool->slow.netdev->ifindex != LOOPBACK_IFINDEX && 130 nla_put_u32(rsp, NETDEV_A_PAGE_POOL_IFINDEX, 131 pool->slow.netdev->ifindex))) 132 goto err_cancel_nest; 133 134 nla_nest_end(rsp, nest); 135 136 if (nla_put_uint(rsp, NETDEV_A_PAGE_POOL_STATS_ALLOC_FAST, 137 stats.alloc_stats.fast) || 138 nla_put_uint(rsp, NETDEV_A_PAGE_POOL_STATS_ALLOC_SLOW, 139 stats.alloc_stats.slow) || 140 nla_put_uint(rsp, NETDEV_A_PAGE_POOL_STATS_ALLOC_SLOW_HIGH_ORDER, 141 stats.alloc_stats.slow_high_order) || 142 nla_put_uint(rsp, NETDEV_A_PAGE_POOL_STATS_ALLOC_EMPTY, 143 stats.alloc_stats.empty) || 144 nla_put_uint(rsp, NETDEV_A_PAGE_POOL_STATS_ALLOC_REFILL, 145 stats.alloc_stats.refill) || 146 nla_put_uint(rsp, NETDEV_A_PAGE_POOL_STATS_ALLOC_WAIVE, 147 stats.alloc_stats.waive) || 148 nla_put_uint(rsp, NETDEV_A_PAGE_POOL_STATS_RECYCLE_CACHED, 149 stats.recycle_stats.cached) || 150 nla_put_uint(rsp, NETDEV_A_PAGE_POOL_STATS_RECYCLE_CACHE_FULL, 151 stats.recycle_stats.cache_full) || 152 nla_put_uint(rsp, NETDEV_A_PAGE_POOL_STATS_RECYCLE_RING, 153 stats.recycle_stats.ring) || 154 nla_put_uint(rsp, NETDEV_A_PAGE_POOL_STATS_RECYCLE_RING_FULL, 155 stats.recycle_stats.ring_full) || 156 nla_put_uint(rsp, NETDEV_A_PAGE_POOL_STATS_RECYCLE_RELEASED_REFCNT, 157 stats.recycle_stats.released_refcnt)) 158 goto err_cancel_msg; 159 160 genlmsg_end(rsp, hdr); 161 162 return 0; 163 err_cancel_nest: 164 nla_nest_cancel(rsp, nest); 165 err_cancel_msg: 166 genlmsg_cancel(rsp, hdr); 167 return -EMSGSIZE; 168 #else 169 GENL_SET_ERR_MSG(info, "kernel built without CONFIG_PAGE_POOL_STATS"); 170 return -EOPNOTSUPP; 171 #endif 172 } 173 174 int netdev_nl_page_pool_stats_get_doit(struct sk_buff *skb, 175 struct genl_info *info) 176 { 177 struct nlattr *tb[ARRAY_SIZE(netdev_page_pool_info_nl_policy)]; 178 struct nlattr *nest; 179 int err; 180 u32 id; 181 182 if (GENL_REQ_ATTR_CHECK(info, NETDEV_A_PAGE_POOL_STATS_INFO)) 183 return -EINVAL; 184 185 nest = info->attrs[NETDEV_A_PAGE_POOL_STATS_INFO]; 186 err = nla_parse_nested(tb, ARRAY_SIZE(tb) - 1, nest, 187 netdev_page_pool_info_nl_policy, 188 info->extack); 189 if (err) 190 return err; 191 192 if (NL_REQ_ATTR_CHECK(info->extack, nest, tb, NETDEV_A_PAGE_POOL_ID)) 193 return -EINVAL; 194 if (tb[NETDEV_A_PAGE_POOL_IFINDEX]) { 195 NL_SET_ERR_MSG_ATTR(info->extack, 196 tb[NETDEV_A_PAGE_POOL_IFINDEX], 197 "selecting by ifindex not supported"); 198 return -EINVAL; 199 } 200 201 id = nla_get_uint(tb[NETDEV_A_PAGE_POOL_ID]); 202 203 return netdev_nl_page_pool_get_do(info, id, page_pool_nl_stats_fill); 204 } 205 206 int netdev_nl_page_pool_stats_get_dumpit(struct sk_buff *skb, 207 struct netlink_callback *cb) 208 { 209 return netdev_nl_page_pool_get_dump(skb, cb, page_pool_nl_stats_fill); 210 } 211 212 static int 213 page_pool_nl_fill(struct sk_buff *rsp, const struct page_pool *pool, 214 const struct genl_info *info) 215 { 216 size_t inflight, refsz; 217 void *hdr; 218 219 hdr = genlmsg_iput(rsp, info); 220 if (!hdr) 221 return -EMSGSIZE; 222 223 if (nla_put_uint(rsp, NETDEV_A_PAGE_POOL_ID, pool->user.id)) 224 goto err_cancel; 225 226 if (pool->slow.netdev->ifindex != LOOPBACK_IFINDEX && 227 nla_put_u32(rsp, NETDEV_A_PAGE_POOL_IFINDEX, 228 pool->slow.netdev->ifindex)) 229 goto err_cancel; 230 if (pool->user.napi_id && 231 nla_put_uint(rsp, NETDEV_A_PAGE_POOL_NAPI_ID, pool->user.napi_id)) 232 goto err_cancel; 233 234 inflight = page_pool_inflight(pool, false); 235 refsz = PAGE_SIZE << pool->p.order; 236 if (nla_put_uint(rsp, NETDEV_A_PAGE_POOL_INFLIGHT, inflight) || 237 nla_put_uint(rsp, NETDEV_A_PAGE_POOL_INFLIGHT_MEM, 238 inflight * refsz)) 239 goto err_cancel; 240 if (pool->user.detach_time && 241 nla_put_uint(rsp, NETDEV_A_PAGE_POOL_DETACH_TIME, 242 pool->user.detach_time)) 243 goto err_cancel; 244 245 genlmsg_end(rsp, hdr); 246 247 return 0; 248 err_cancel: 249 genlmsg_cancel(rsp, hdr); 250 return -EMSGSIZE; 251 } 252 253 static void netdev_nl_page_pool_event(const struct page_pool *pool, u32 cmd) 254 { 255 struct genl_info info; 256 struct sk_buff *ntf; 257 struct net *net; 258 259 lockdep_assert_held(&page_pools_lock); 260 261 /* 'invisible' page pools don't matter */ 262 if (hlist_unhashed(&pool->user.list)) 263 return; 264 net = dev_net(pool->slow.netdev); 265 266 if (!genl_has_listeners(&netdev_nl_family, net, NETDEV_NLGRP_PAGE_POOL)) 267 return; 268 269 genl_info_init_ntf(&info, &netdev_nl_family, cmd); 270 271 ntf = genlmsg_new(GENLMSG_DEFAULT_SIZE, GFP_KERNEL); 272 if (!ntf) 273 return; 274 275 if (page_pool_nl_fill(ntf, pool, &info)) { 276 nlmsg_free(ntf); 277 return; 278 } 279 280 genlmsg_multicast_netns(&netdev_nl_family, net, ntf, 281 0, NETDEV_NLGRP_PAGE_POOL, GFP_KERNEL); 282 } 283 284 int netdev_nl_page_pool_get_doit(struct sk_buff *skb, struct genl_info *info) 285 { 286 u32 id; 287 288 if (GENL_REQ_ATTR_CHECK(info, NETDEV_A_PAGE_POOL_ID)) 289 return -EINVAL; 290 291 id = nla_get_uint(info->attrs[NETDEV_A_PAGE_POOL_ID]); 292 293 return netdev_nl_page_pool_get_do(info, id, page_pool_nl_fill); 294 } 295 296 int netdev_nl_page_pool_get_dumpit(struct sk_buff *skb, 297 struct netlink_callback *cb) 298 { 299 return netdev_nl_page_pool_get_dump(skb, cb, page_pool_nl_fill); 300 } 301 302 int page_pool_list(struct page_pool *pool) 303 { 304 static u32 id_alloc_next; 305 int err; 306 307 mutex_lock(&page_pools_lock); 308 err = xa_alloc_cyclic(&page_pools, &pool->user.id, pool, xa_limit_32b, 309 &id_alloc_next, GFP_KERNEL); 310 if (err < 0) 311 goto err_unlock; 312 313 INIT_HLIST_NODE(&pool->user.list); 314 if (pool->slow.netdev) { 315 hlist_add_head(&pool->user.list, 316 &pool->slow.netdev->page_pools); 317 pool->user.napi_id = pool->p.napi ? pool->p.napi->napi_id : 0; 318 319 netdev_nl_page_pool_event(pool, NETDEV_CMD_PAGE_POOL_ADD_NTF); 320 } 321 322 mutex_unlock(&page_pools_lock); 323 return 0; 324 325 err_unlock: 326 mutex_unlock(&page_pools_lock); 327 return err; 328 } 329 330 void page_pool_detached(struct page_pool *pool) 331 { 332 mutex_lock(&page_pools_lock); 333 pool->user.detach_time = ktime_get_boottime_seconds(); 334 netdev_nl_page_pool_event(pool, NETDEV_CMD_PAGE_POOL_CHANGE_NTF); 335 mutex_unlock(&page_pools_lock); 336 } 337 338 void page_pool_unlist(struct page_pool *pool) 339 { 340 mutex_lock(&page_pools_lock); 341 netdev_nl_page_pool_event(pool, NETDEV_CMD_PAGE_POOL_DEL_NTF); 342 xa_erase(&page_pools, pool->user.id); 343 if (!hlist_unhashed(&pool->user.list)) 344 hlist_del(&pool->user.list); 345 mutex_unlock(&page_pools_lock); 346 } 347 348 static void page_pool_unreg_netdev_wipe(struct net_device *netdev) 349 { 350 struct page_pool *pool; 351 struct hlist_node *n; 352 353 mutex_lock(&page_pools_lock); 354 hlist_for_each_entry_safe(pool, n, &netdev->page_pools, user.list) { 355 hlist_del_init(&pool->user.list); 356 pool->slow.netdev = NET_PTR_POISON; 357 } 358 mutex_unlock(&page_pools_lock); 359 } 360 361 static void page_pool_unreg_netdev(struct net_device *netdev) 362 { 363 struct page_pool *pool, *last; 364 struct net_device *lo; 365 366 lo = dev_net(netdev)->loopback_dev; 367 368 mutex_lock(&page_pools_lock); 369 last = NULL; 370 hlist_for_each_entry(pool, &netdev->page_pools, user.list) { 371 pool->slow.netdev = lo; 372 netdev_nl_page_pool_event(pool, 373 NETDEV_CMD_PAGE_POOL_CHANGE_NTF); 374 last = pool; 375 } 376 if (last) 377 hlist_splice_init(&netdev->page_pools, &last->user.list, 378 &lo->page_pools); 379 mutex_unlock(&page_pools_lock); 380 } 381 382 static int 383 page_pool_netdevice_event(struct notifier_block *nb, 384 unsigned long event, void *ptr) 385 { 386 struct net_device *netdev = netdev_notifier_info_to_dev(ptr); 387 388 if (event != NETDEV_UNREGISTER) 389 return NOTIFY_DONE; 390 391 if (hlist_empty(&netdev->page_pools)) 392 return NOTIFY_OK; 393 394 if (netdev->ifindex != LOOPBACK_IFINDEX) 395 page_pool_unreg_netdev(netdev); 396 else 397 page_pool_unreg_netdev_wipe(netdev); 398 return NOTIFY_OK; 399 } 400 401 static struct notifier_block page_pool_netdevice_nb = { 402 .notifier_call = page_pool_netdevice_event, 403 }; 404 405 static int __init page_pool_user_init(void) 406 { 407 return register_netdevice_notifier(&page_pool_netdevice_nb); 408 } 409 410 subsys_initcall(page_pool_user_init); 411