From 76cb841cb886eef6b3bee341a2266c76578724ad Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Mon, 6 May 2024 03:02:30 +0200 Subject: Adding upstream version 4.19.249. Signed-off-by: Daniel Baumann --- drivers/net/netdevsim/bpf.c | 652 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 652 insertions(+) create mode 100644 drivers/net/netdevsim/bpf.c (limited to 'drivers/net/netdevsim/bpf.c') diff --git a/drivers/net/netdevsim/bpf.c b/drivers/net/netdevsim/bpf.c new file mode 100644 index 000000000..12f100392 --- /dev/null +++ b/drivers/net/netdevsim/bpf.c @@ -0,0 +1,652 @@ +/* + * Copyright (C) 2017 Netronome Systems, Inc. + * + * This software is licensed under the GNU General License Version 2, + * June 1991 as shown in the file COPYING in the top-level directory of this + * source tree. + * + * THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS" + * WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, + * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS + * FOR A PARTICULAR PURPOSE. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE + * OF THE PROGRAM IS WITH YOU. SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME + * THE COST OF ALL NECESSARY SERVICING, REPAIR OR CORRECTION. + */ + +#include +#include +#include +#include +#include +#include +#include + +#include "netdevsim.h" + +#define pr_vlog(env, fmt, ...) \ + bpf_verifier_log_write(env, "[netdevsim] " fmt, ##__VA_ARGS__) + +struct nsim_bpf_bound_prog { + struct netdevsim *ns; + struct bpf_prog *prog; + struct dentry *ddir; + const char *state; + bool is_loaded; + struct list_head l; +}; + +#define NSIM_BPF_MAX_KEYS 2 + +struct nsim_bpf_bound_map { + struct netdevsim *ns; + struct bpf_offloaded_map *map; + struct mutex mutex; + struct nsim_map_entry { + void *key; + void *value; + } entry[NSIM_BPF_MAX_KEYS]; + struct list_head l; +}; + +static int nsim_debugfs_bpf_string_read(struct seq_file *file, void *data) +{ + const char **str = file->private; + + if (*str) + seq_printf(file, "%s\n", *str); + + return 0; +} + +static int nsim_debugfs_bpf_string_open(struct inode *inode, struct file *f) +{ + return single_open(f, nsim_debugfs_bpf_string_read, inode->i_private); +} + +static const struct file_operations nsim_bpf_string_fops = { + .owner = THIS_MODULE, + .open = nsim_debugfs_bpf_string_open, + .release = single_release, + .read = seq_read, + .llseek = seq_lseek +}; + +static int +nsim_bpf_verify_insn(struct bpf_verifier_env *env, int insn_idx, int prev_insn) +{ + struct nsim_bpf_bound_prog *state; + + state = env->prog->aux->offload->dev_priv; + if (state->ns->bpf_bind_verifier_delay && !insn_idx) + msleep(state->ns->bpf_bind_verifier_delay); + + if (insn_idx == env->prog->len - 1) + pr_vlog(env, "Hello from netdevsim!\n"); + + return 0; +} + +static const struct bpf_prog_offload_ops nsim_bpf_analyzer_ops = { + .insn_hook = nsim_bpf_verify_insn, +}; + +static bool nsim_xdp_offload_active(struct netdevsim *ns) +{ + return ns->xdp_hw.prog; +} + +static void nsim_prog_set_loaded(struct bpf_prog *prog, bool loaded) +{ + struct nsim_bpf_bound_prog *state; + + if (!prog || !prog->aux->offload) + return; + + state = prog->aux->offload->dev_priv; + state->is_loaded = loaded; +} + +static int +nsim_bpf_offload(struct netdevsim *ns, struct bpf_prog *prog, bool oldprog) +{ + nsim_prog_set_loaded(ns->bpf_offloaded, false); + + WARN(!!ns->bpf_offloaded != oldprog, + "bad offload state, expected offload %sto be active", + oldprog ? "" : "not "); + ns->bpf_offloaded = prog; + ns->bpf_offloaded_id = prog ? prog->aux->id : 0; + nsim_prog_set_loaded(prog, true); + + return 0; +} + +int nsim_bpf_setup_tc_block_cb(enum tc_setup_type type, + void *type_data, void *cb_priv) +{ + struct tc_cls_bpf_offload *cls_bpf = type_data; + struct bpf_prog *prog = cls_bpf->prog; + struct netdevsim *ns = cb_priv; + struct bpf_prog *oldprog; + + if (type != TC_SETUP_CLSBPF) { + NSIM_EA(cls_bpf->common.extack, + "only offload of BPF classifiers supported"); + return -EOPNOTSUPP; + } + + if (!tc_cls_can_offload_and_chain0(ns->netdev, &cls_bpf->common)) + return -EOPNOTSUPP; + + if (cls_bpf->common.protocol != htons(ETH_P_ALL)) { + NSIM_EA(cls_bpf->common.extack, + "only ETH_P_ALL supported as filter protocol"); + return -EOPNOTSUPP; + } + + if (!ns->bpf_tc_accept) { + NSIM_EA(cls_bpf->common.extack, + "netdevsim configured to reject BPF TC offload"); + return -EOPNOTSUPP; + } + /* Note: progs without skip_sw will probably not be dev bound */ + if (prog && !prog->aux->offload && !ns->bpf_tc_non_bound_accept) { + NSIM_EA(cls_bpf->common.extack, + "netdevsim configured to reject unbound programs"); + return -EOPNOTSUPP; + } + + if (cls_bpf->command != TC_CLSBPF_OFFLOAD) + return -EOPNOTSUPP; + + oldprog = cls_bpf->oldprog; + + /* Don't remove if oldprog doesn't match driver's state */ + if (ns->bpf_offloaded != oldprog) { + oldprog = NULL; + if (!cls_bpf->prog) + return 0; + if (ns->bpf_offloaded) { + NSIM_EA(cls_bpf->common.extack, + "driver and netdev offload states mismatch"); + return -EBUSY; + } + } + + return nsim_bpf_offload(ns, cls_bpf->prog, oldprog); +} + +int nsim_bpf_disable_tc(struct netdevsim *ns) +{ + if (ns->bpf_offloaded && !nsim_xdp_offload_active(ns)) + return -EBUSY; + return 0; +} + +static int nsim_xdp_offload_prog(struct netdevsim *ns, struct netdev_bpf *bpf) +{ + if (!nsim_xdp_offload_active(ns) && !bpf->prog) + return 0; + if (!nsim_xdp_offload_active(ns) && bpf->prog && ns->bpf_offloaded) { + NSIM_EA(bpf->extack, "TC program is already loaded"); + return -EBUSY; + } + + return nsim_bpf_offload(ns, bpf->prog, nsim_xdp_offload_active(ns)); +} + +static int +nsim_xdp_set_prog(struct netdevsim *ns, struct netdev_bpf *bpf, + struct xdp_attachment_info *xdp) +{ + int err; + + if (!xdp_attachment_flags_ok(xdp, bpf)) + return -EBUSY; + + if (bpf->command == XDP_SETUP_PROG && !ns->bpf_xdpdrv_accept) { + NSIM_EA(bpf->extack, "driver XDP disabled in DebugFS"); + return -EOPNOTSUPP; + } + if (bpf->command == XDP_SETUP_PROG_HW && !ns->bpf_xdpoffload_accept) { + NSIM_EA(bpf->extack, "XDP offload disabled in DebugFS"); + return -EOPNOTSUPP; + } + + if (bpf->command == XDP_SETUP_PROG_HW) { + err = nsim_xdp_offload_prog(ns, bpf); + if (err) + return err; + } + + xdp_attachment_setup(xdp, bpf); + + return 0; +} + +static int nsim_bpf_create_prog(struct netdevsim *ns, struct bpf_prog *prog) +{ + struct nsim_bpf_bound_prog *state; + char name[16]; + + state = kzalloc(sizeof(*state), GFP_KERNEL); + if (!state) + return -ENOMEM; + + state->ns = ns; + state->prog = prog; + state->state = "verify"; + + /* Program id is not populated yet when we create the state. */ + sprintf(name, "%u", ns->sdev->prog_id_gen++); + state->ddir = debugfs_create_dir(name, ns->sdev->ddir_bpf_bound_progs); + if (IS_ERR_OR_NULL(state->ddir)) { + kfree(state); + return -ENOMEM; + } + + debugfs_create_u32("id", 0400, state->ddir, &prog->aux->id); + debugfs_create_file("state", 0400, state->ddir, + &state->state, &nsim_bpf_string_fops); + debugfs_create_bool("loaded", 0400, state->ddir, &state->is_loaded); + + list_add_tail(&state->l, &ns->sdev->bpf_bound_progs); + + prog->aux->offload->dev_priv = state; + + return 0; +} + +static void nsim_bpf_destroy_prog(struct bpf_prog *prog) +{ + struct nsim_bpf_bound_prog *state; + + state = prog->aux->offload->dev_priv; + WARN(state->is_loaded, + "offload state destroyed while program still bound"); + debugfs_remove_recursive(state->ddir); + list_del(&state->l); + kfree(state); +} + +static int nsim_setup_prog_checks(struct netdevsim *ns, struct netdev_bpf *bpf) +{ + if (bpf->prog && bpf->prog->aux->offload) { + NSIM_EA(bpf->extack, "attempt to load offloaded prog to drv"); + return -EINVAL; + } + if (ns->netdev->mtu > NSIM_XDP_MAX_MTU) { + NSIM_EA(bpf->extack, "MTU too large w/ XDP enabled"); + return -EINVAL; + } + return 0; +} + +static int +nsim_setup_prog_hw_checks(struct netdevsim *ns, struct netdev_bpf *bpf) +{ + struct nsim_bpf_bound_prog *state; + + if (!bpf->prog) + return 0; + + if (!bpf->prog->aux->offload) { + NSIM_EA(bpf->extack, "xdpoffload of non-bound program"); + return -EINVAL; + } + if (!bpf_offload_dev_match(bpf->prog, ns->netdev)) { + NSIM_EA(bpf->extack, "program bound to different dev"); + return -EINVAL; + } + + state = bpf->prog->aux->offload->dev_priv; + if (WARN_ON(strcmp(state->state, "xlated"))) { + NSIM_EA(bpf->extack, "offloading program in bad state"); + return -EINVAL; + } + return 0; +} + +static bool +nsim_map_key_match(struct bpf_map *map, struct nsim_map_entry *e, void *key) +{ + return e->key && !memcmp(key, e->key, map->key_size); +} + +static int nsim_map_key_find(struct bpf_offloaded_map *offmap, void *key) +{ + struct nsim_bpf_bound_map *nmap = offmap->dev_priv; + unsigned int i; + + for (i = 0; i < ARRAY_SIZE(nmap->entry); i++) + if (nsim_map_key_match(&offmap->map, &nmap->entry[i], key)) + return i; + + return -ENOENT; +} + +static int +nsim_map_alloc_elem(struct bpf_offloaded_map *offmap, unsigned int idx) +{ + struct nsim_bpf_bound_map *nmap = offmap->dev_priv; + + nmap->entry[idx].key = kmalloc(offmap->map.key_size, GFP_USER); + if (!nmap->entry[idx].key) + return -ENOMEM; + nmap->entry[idx].value = kmalloc(offmap->map.value_size, GFP_USER); + if (!nmap->entry[idx].value) { + kfree(nmap->entry[idx].key); + nmap->entry[idx].key = NULL; + return -ENOMEM; + } + + return 0; +} + +static int +nsim_map_get_next_key(struct bpf_offloaded_map *offmap, + void *key, void *next_key) +{ + struct nsim_bpf_bound_map *nmap = offmap->dev_priv; + int idx = -ENOENT; + + mutex_lock(&nmap->mutex); + + if (key) + idx = nsim_map_key_find(offmap, key); + if (idx == -ENOENT) + idx = 0; + else + idx++; + + for (; idx < ARRAY_SIZE(nmap->entry); idx++) { + if (nmap->entry[idx].key) { + memcpy(next_key, nmap->entry[idx].key, + offmap->map.key_size); + break; + } + } + + mutex_unlock(&nmap->mutex); + + if (idx == ARRAY_SIZE(nmap->entry)) + return -ENOENT; + return 0; +} + +static int +nsim_map_lookup_elem(struct bpf_offloaded_map *offmap, void *key, void *value) +{ + struct nsim_bpf_bound_map *nmap = offmap->dev_priv; + int idx; + + mutex_lock(&nmap->mutex); + + idx = nsim_map_key_find(offmap, key); + if (idx >= 0) + memcpy(value, nmap->entry[idx].value, offmap->map.value_size); + + mutex_unlock(&nmap->mutex); + + return idx < 0 ? idx : 0; +} + +static int +nsim_map_update_elem(struct bpf_offloaded_map *offmap, + void *key, void *value, u64 flags) +{ + struct nsim_bpf_bound_map *nmap = offmap->dev_priv; + int idx, err = 0; + + mutex_lock(&nmap->mutex); + + idx = nsim_map_key_find(offmap, key); + if (idx < 0 && flags == BPF_EXIST) { + err = idx; + goto exit_unlock; + } + if (idx >= 0 && flags == BPF_NOEXIST) { + err = -EEXIST; + goto exit_unlock; + } + + if (idx < 0) { + for (idx = 0; idx < ARRAY_SIZE(nmap->entry); idx++) + if (!nmap->entry[idx].key) + break; + if (idx == ARRAY_SIZE(nmap->entry)) { + err = -E2BIG; + goto exit_unlock; + } + + err = nsim_map_alloc_elem(offmap, idx); + if (err) + goto exit_unlock; + } + + memcpy(nmap->entry[idx].key, key, offmap->map.key_size); + memcpy(nmap->entry[idx].value, value, offmap->map.value_size); +exit_unlock: + mutex_unlock(&nmap->mutex); + + return err; +} + +static int nsim_map_delete_elem(struct bpf_offloaded_map *offmap, void *key) +{ + struct nsim_bpf_bound_map *nmap = offmap->dev_priv; + int idx; + + if (offmap->map.map_type == BPF_MAP_TYPE_ARRAY) + return -EINVAL; + + mutex_lock(&nmap->mutex); + + idx = nsim_map_key_find(offmap, key); + if (idx >= 0) { + kfree(nmap->entry[idx].key); + kfree(nmap->entry[idx].value); + memset(&nmap->entry[idx], 0, sizeof(nmap->entry[idx])); + } + + mutex_unlock(&nmap->mutex); + + return idx < 0 ? idx : 0; +} + +static const struct bpf_map_dev_ops nsim_bpf_map_ops = { + .map_get_next_key = nsim_map_get_next_key, + .map_lookup_elem = nsim_map_lookup_elem, + .map_update_elem = nsim_map_update_elem, + .map_delete_elem = nsim_map_delete_elem, +}; + +static int +nsim_bpf_map_alloc(struct netdevsim *ns, struct bpf_offloaded_map *offmap) +{ + struct nsim_bpf_bound_map *nmap; + int i, err; + + if (WARN_ON(offmap->map.map_type != BPF_MAP_TYPE_ARRAY && + offmap->map.map_type != BPF_MAP_TYPE_HASH)) + return -EINVAL; + if (offmap->map.max_entries > NSIM_BPF_MAX_KEYS) + return -ENOMEM; + if (offmap->map.map_flags) + return -EINVAL; + + nmap = kzalloc(sizeof(*nmap), GFP_USER); + if (!nmap) + return -ENOMEM; + + offmap->dev_priv = nmap; + nmap->ns = ns; + nmap->map = offmap; + mutex_init(&nmap->mutex); + + if (offmap->map.map_type == BPF_MAP_TYPE_ARRAY) { + for (i = 0; i < ARRAY_SIZE(nmap->entry); i++) { + u32 *key; + + err = nsim_map_alloc_elem(offmap, i); + if (err) + goto err_free; + key = nmap->entry[i].key; + *key = i; + memset(nmap->entry[i].value, 0, offmap->map.value_size); + } + } + + offmap->dev_ops = &nsim_bpf_map_ops; + list_add_tail(&nmap->l, &ns->sdev->bpf_bound_maps); + + return 0; + +err_free: + while (--i >= 0) { + kfree(nmap->entry[i].key); + kfree(nmap->entry[i].value); + } + kfree(nmap); + return err; +} + +static void nsim_bpf_map_free(struct bpf_offloaded_map *offmap) +{ + struct nsim_bpf_bound_map *nmap = offmap->dev_priv; + unsigned int i; + + for (i = 0; i < ARRAY_SIZE(nmap->entry); i++) { + kfree(nmap->entry[i].key); + kfree(nmap->entry[i].value); + } + list_del_init(&nmap->l); + mutex_destroy(&nmap->mutex); + kfree(nmap); +} + +int nsim_bpf(struct net_device *dev, struct netdev_bpf *bpf) +{ + struct netdevsim *ns = netdev_priv(dev); + struct nsim_bpf_bound_prog *state; + int err; + + ASSERT_RTNL(); + + switch (bpf->command) { + case BPF_OFFLOAD_VERIFIER_PREP: + if (!ns->bpf_bind_accept) + return -EOPNOTSUPP; + + err = nsim_bpf_create_prog(ns, bpf->verifier.prog); + if (err) + return err; + + bpf->verifier.ops = &nsim_bpf_analyzer_ops; + return 0; + case BPF_OFFLOAD_TRANSLATE: + state = bpf->offload.prog->aux->offload->dev_priv; + + state->state = "xlated"; + return 0; + case BPF_OFFLOAD_DESTROY: + nsim_bpf_destroy_prog(bpf->offload.prog); + return 0; + case XDP_QUERY_PROG: + return xdp_attachment_query(&ns->xdp, bpf); + case XDP_QUERY_PROG_HW: + return xdp_attachment_query(&ns->xdp_hw, bpf); + case XDP_SETUP_PROG: + err = nsim_setup_prog_checks(ns, bpf); + if (err) + return err; + + return nsim_xdp_set_prog(ns, bpf, &ns->xdp); + case XDP_SETUP_PROG_HW: + err = nsim_setup_prog_hw_checks(ns, bpf); + if (err) + return err; + + return nsim_xdp_set_prog(ns, bpf, &ns->xdp_hw); + case BPF_OFFLOAD_MAP_ALLOC: + if (!ns->bpf_map_accept) + return -EOPNOTSUPP; + + return nsim_bpf_map_alloc(ns, bpf->offmap); + case BPF_OFFLOAD_MAP_FREE: + nsim_bpf_map_free(bpf->offmap); + return 0; + default: + return -EINVAL; + } +} + +int nsim_bpf_init(struct netdevsim *ns) +{ + int err; + + if (ns->sdev->refcnt == 1) { + INIT_LIST_HEAD(&ns->sdev->bpf_bound_progs); + INIT_LIST_HEAD(&ns->sdev->bpf_bound_maps); + + ns->sdev->ddir_bpf_bound_progs = + debugfs_create_dir("bpf_bound_progs", ns->sdev->ddir); + if (IS_ERR_OR_NULL(ns->sdev->ddir_bpf_bound_progs)) + return -ENOMEM; + + ns->sdev->bpf_dev = bpf_offload_dev_create(); + err = PTR_ERR_OR_ZERO(ns->sdev->bpf_dev); + if (err) + return err; + } + + err = bpf_offload_dev_netdev_register(ns->sdev->bpf_dev, ns->netdev); + if (err) + goto err_destroy_bdev; + + debugfs_create_u32("bpf_offloaded_id", 0400, ns->ddir, + &ns->bpf_offloaded_id); + + ns->bpf_bind_accept = true; + debugfs_create_bool("bpf_bind_accept", 0600, ns->ddir, + &ns->bpf_bind_accept); + debugfs_create_u32("bpf_bind_verifier_delay", 0600, ns->ddir, + &ns->bpf_bind_verifier_delay); + + ns->bpf_tc_accept = true; + debugfs_create_bool("bpf_tc_accept", 0600, ns->ddir, + &ns->bpf_tc_accept); + debugfs_create_bool("bpf_tc_non_bound_accept", 0600, ns->ddir, + &ns->bpf_tc_non_bound_accept); + ns->bpf_xdpdrv_accept = true; + debugfs_create_bool("bpf_xdpdrv_accept", 0600, ns->ddir, + &ns->bpf_xdpdrv_accept); + ns->bpf_xdpoffload_accept = true; + debugfs_create_bool("bpf_xdpoffload_accept", 0600, ns->ddir, + &ns->bpf_xdpoffload_accept); + + ns->bpf_map_accept = true; + debugfs_create_bool("bpf_map_accept", 0600, ns->ddir, + &ns->bpf_map_accept); + + return 0; + +err_destroy_bdev: + if (ns->sdev->refcnt == 1) + bpf_offload_dev_destroy(ns->sdev->bpf_dev); + return err; +} + +void nsim_bpf_uninit(struct netdevsim *ns) +{ + WARN_ON(ns->xdp.prog); + WARN_ON(ns->xdp_hw.prog); + WARN_ON(ns->bpf_offloaded); + bpf_offload_dev_netdev_unregister(ns->sdev->bpf_dev, ns->netdev); + + if (ns->sdev->refcnt == 1) { + WARN_ON(!list_empty(&ns->sdev->bpf_bound_progs)); + WARN_ON(!list_empty(&ns->sdev->bpf_bound_maps)); + bpf_offload_dev_destroy(ns->sdev->bpf_dev); + } +} -- cgit v1.2.3