v4.19.13 snapshot.
diff --git a/drivers/net/netdevsim/bpf.c b/drivers/net/netdevsim/bpf.c
new file mode 100644
index 0000000..8144420
--- /dev/null
+++ b/drivers/net/netdevsim/bpf.c
@@ -0,0 +1,651 @@
+/*
+ * 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 <linux/bpf.h>
+#include <linux/bpf_verifier.h>
+#include <linux/debugfs.h>
+#include <linux/kernel.h>
+#include <linux/mutex.h>
+#include <linux/rtnetlink.h>
+#include <net/pkt_cls.h>
+
+#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;
+ }
+ }
+
+ 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);
+ }
+}