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authorLinus Torvalds <torvalds@linux-foundation.org>2019-09-18 12:34:53 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2019-09-18 12:34:53 -0700
commit81160dda9a7aad13c04e78bb2cfd3c4630e3afab (patch)
tree4bf79ffa9fc7dc5e2915ff978778c3402c491113 /kernel/bpf/devmap.c
parent8b53c76533aa4356602aea98f98a2f3b4051464c (diff)
parent1bab8d4c488be22d57f9dd09968c90a0ddc413bf (diff)
downloadlinux-81160dda9a7aad13c04e78bb2cfd3c4630e3afab.tar.bz2
Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next
Pull networking updates from David Miller: 1) Support IPV6 RA Captive Portal Identifier, from Maciej Żenczykowski. 2) Use bio_vec in the networking instead of custom skb_frag_t, from Matthew Wilcox. 3) Make use of xmit_more in r8169 driver, from Heiner Kallweit. 4) Add devmap_hash to xdp, from Toke Høiland-Jørgensen. 5) Support all variants of 5750X bnxt_en chips, from Michael Chan. 6) More RTNL avoidance work in the core and mlx5 driver, from Vlad Buslov. 7) Add TCP syn cookies bpf helper, from Petar Penkov. 8) Add 'nettest' to selftests and use it, from David Ahern. 9) Add extack support to drop_monitor, add packet alert mode and support for HW drops, from Ido Schimmel. 10) Add VLAN offload to stmmac, from Jose Abreu. 11) Lots of devm_platform_ioremap_resource() conversions, from YueHaibing. 12) Add IONIC driver, from Shannon Nelson. 13) Several kTLS cleanups, from Jakub Kicinski. * git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1930 commits) mlxsw: spectrum_buffers: Add the ability to query the CPU port's shared buffer mlxsw: spectrum: Register CPU port with devlink mlxsw: spectrum_buffers: Prevent changing CPU port's configuration net: ena: fix incorrect update of intr_delay_resolution net: ena: fix retrieval of nonadaptive interrupt moderation intervals net: ena: fix update of interrupt moderation register net: ena: remove all old adaptive rx interrupt moderation code from ena_com net: ena: remove ena_restore_ethtool_params() and relevant fields net: ena: remove old adaptive interrupt moderation code from ena_netdev net: ena: remove code duplication in ena_com_update_nonadaptive_moderation_interval _*() net: ena: enable the interrupt_moderation in driver_supported_features net: ena: reimplement set/get_coalesce() net: ena: switch to dim algorithm for rx adaptive interrupt moderation net: ena: add intr_moder_rx_interval to struct ena_com_dev and use it net: phy: adin: implement Energy Detect Powerdown mode via phy-tunable ethtool: implement Energy Detect Powerdown support via phy-tunable xen-netfront: do not assume sk_buff_head list is empty in error handling s390/ctcm: Delete unnecessary checks before the macro call “dev_kfree_skb” net: ena: don't wake up tx queue when down drop_monitor: Better sanitize notified packets ...
Diffstat (limited to 'kernel/bpf/devmap.c')
-rw-r--r--kernel/bpf/devmap.c339
1 files changed, 288 insertions, 51 deletions
diff --git a/kernel/bpf/devmap.c b/kernel/bpf/devmap.c
index d83cf8ccc872..d27f3b60ff6d 100644
--- a/kernel/bpf/devmap.c
+++ b/kernel/bpf/devmap.c
@@ -37,6 +37,12 @@
* notifier hook walks the map we know that new dev references can not be
* added by the user because core infrastructure ensures dev_get_by_index()
* calls will fail at this point.
+ *
+ * The devmap_hash type is a map type which interprets keys as ifindexes and
+ * indexes these using a hashmap. This allows maps that use ifindex as key to be
+ * densely packed instead of having holes in the lookup array for unused
+ * ifindexes. The setup and packet enqueue/send code is shared between the two
+ * types of devmap; only the lookup and insertion is different.
*/
#include <linux/bpf.h>
#include <net/xdp.h>
@@ -59,10 +65,11 @@ struct xdp_bulk_queue {
struct bpf_dtab_netdev {
struct net_device *dev; /* must be first member, due to tracepoint */
+ struct hlist_node index_hlist;
struct bpf_dtab *dtab;
- unsigned int bit;
struct xdp_bulk_queue __percpu *bulkq;
struct rcu_head rcu;
+ unsigned int idx; /* keep track of map index for tracepoint */
};
struct bpf_dtab {
@@ -70,33 +77,45 @@ struct bpf_dtab {
struct bpf_dtab_netdev **netdev_map;
struct list_head __percpu *flush_list;
struct list_head list;
+
+ /* these are only used for DEVMAP_HASH type maps */
+ struct hlist_head *dev_index_head;
+ spinlock_t index_lock;
+ unsigned int items;
+ u32 n_buckets;
};
static DEFINE_SPINLOCK(dev_map_lock);
static LIST_HEAD(dev_map_list);
-static struct bpf_map *dev_map_alloc(union bpf_attr *attr)
+static struct hlist_head *dev_map_create_hash(unsigned int entries)
+{
+ int i;
+ struct hlist_head *hash;
+
+ hash = kmalloc_array(entries, sizeof(*hash), GFP_KERNEL);
+ if (hash != NULL)
+ for (i = 0; i < entries; i++)
+ INIT_HLIST_HEAD(&hash[i]);
+
+ return hash;
+}
+
+static int dev_map_init_map(struct bpf_dtab *dtab, union bpf_attr *attr)
{
- struct bpf_dtab *dtab;
int err, cpu;
u64 cost;
- if (!capable(CAP_NET_ADMIN))
- return ERR_PTR(-EPERM);
-
/* check sanity of attributes */
if (attr->max_entries == 0 || attr->key_size != 4 ||
attr->value_size != 4 || attr->map_flags & ~DEV_CREATE_FLAG_MASK)
- return ERR_PTR(-EINVAL);
+ return -EINVAL;
/* Lookup returns a pointer straight to dev->ifindex, so make sure the
* verifier prevents writes from the BPF side
*/
attr->map_flags |= BPF_F_RDONLY_PROG;
- dtab = kzalloc(sizeof(*dtab), GFP_USER);
- if (!dtab)
- return ERR_PTR(-ENOMEM);
bpf_map_init_from_attr(&dtab->map, attr);
@@ -104,12 +123,18 @@ static struct bpf_map *dev_map_alloc(union bpf_attr *attr)
cost = (u64) dtab->map.max_entries * sizeof(struct bpf_dtab_netdev *);
cost += sizeof(struct list_head) * num_possible_cpus();
+ if (attr->map_type == BPF_MAP_TYPE_DEVMAP_HASH) {
+ dtab->n_buckets = roundup_pow_of_two(dtab->map.max_entries);
+
+ if (!dtab->n_buckets) /* Overflow check */
+ return -EINVAL;
+ cost += sizeof(struct hlist_head) * dtab->n_buckets;
+ }
+
/* if map size is larger than memlock limit, reject it */
err = bpf_map_charge_init(&dtab->map.memory, cost);
if (err)
- goto free_dtab;
-
- err = -ENOMEM;
+ return -EINVAL;
dtab->flush_list = alloc_percpu(struct list_head);
if (!dtab->flush_list)
@@ -124,19 +149,48 @@ static struct bpf_map *dev_map_alloc(union bpf_attr *attr)
if (!dtab->netdev_map)
goto free_percpu;
- spin_lock(&dev_map_lock);
- list_add_tail_rcu(&dtab->list, &dev_map_list);
- spin_unlock(&dev_map_lock);
+ if (attr->map_type == BPF_MAP_TYPE_DEVMAP_HASH) {
+ dtab->dev_index_head = dev_map_create_hash(dtab->n_buckets);
+ if (!dtab->dev_index_head)
+ goto free_map_area;
- return &dtab->map;
+ spin_lock_init(&dtab->index_lock);
+ }
+ return 0;
+
+free_map_area:
+ bpf_map_area_free(dtab->netdev_map);
free_percpu:
free_percpu(dtab->flush_list);
free_charge:
bpf_map_charge_finish(&dtab->map.memory);
-free_dtab:
- kfree(dtab);
- return ERR_PTR(err);
+ return -ENOMEM;
+}
+
+static struct bpf_map *dev_map_alloc(union bpf_attr *attr)
+{
+ struct bpf_dtab *dtab;
+ int err;
+
+ if (!capable(CAP_NET_ADMIN))
+ return ERR_PTR(-EPERM);
+
+ dtab = kzalloc(sizeof(*dtab), GFP_USER);
+ if (!dtab)
+ return ERR_PTR(-ENOMEM);
+
+ err = dev_map_init_map(dtab, attr);
+ if (err) {
+ kfree(dtab);
+ return ERR_PTR(err);
+ }
+
+ spin_lock(&dev_map_lock);
+ list_add_tail_rcu(&dtab->list, &dev_map_list);
+ spin_unlock(&dev_map_lock);
+
+ return &dtab->map;
}
static void dev_map_free(struct bpf_map *map)
@@ -188,6 +242,7 @@ static void dev_map_free(struct bpf_map *map)
free_percpu(dtab->flush_list);
bpf_map_area_free(dtab->netdev_map);
+ kfree(dtab->dev_index_head);
kfree(dtab);
}
@@ -208,6 +263,70 @@ static int dev_map_get_next_key(struct bpf_map *map, void *key, void *next_key)
return 0;
}
+static inline struct hlist_head *dev_map_index_hash(struct bpf_dtab *dtab,
+ int idx)
+{
+ return &dtab->dev_index_head[idx & (dtab->n_buckets - 1)];
+}
+
+struct bpf_dtab_netdev *__dev_map_hash_lookup_elem(struct bpf_map *map, u32 key)
+{
+ struct bpf_dtab *dtab = container_of(map, struct bpf_dtab, map);
+ struct hlist_head *head = dev_map_index_hash(dtab, key);
+ struct bpf_dtab_netdev *dev;
+
+ hlist_for_each_entry_rcu(dev, head, index_hlist)
+ if (dev->idx == key)
+ return dev;
+
+ return NULL;
+}
+
+static int dev_map_hash_get_next_key(struct bpf_map *map, void *key,
+ void *next_key)
+{
+ struct bpf_dtab *dtab = container_of(map, struct bpf_dtab, map);
+ u32 idx, *next = next_key;
+ struct bpf_dtab_netdev *dev, *next_dev;
+ struct hlist_head *head;
+ int i = 0;
+
+ if (!key)
+ goto find_first;
+
+ idx = *(u32 *)key;
+
+ dev = __dev_map_hash_lookup_elem(map, idx);
+ if (!dev)
+ goto find_first;
+
+ next_dev = hlist_entry_safe(rcu_dereference_raw(hlist_next_rcu(&dev->index_hlist)),
+ struct bpf_dtab_netdev, index_hlist);
+
+ if (next_dev) {
+ *next = next_dev->idx;
+ return 0;
+ }
+
+ i = idx & (dtab->n_buckets - 1);
+ i++;
+
+ find_first:
+ for (; i < dtab->n_buckets; i++) {
+ head = dev_map_index_hash(dtab, i);
+
+ next_dev = hlist_entry_safe(rcu_dereference_raw(hlist_first_rcu(head)),
+ struct bpf_dtab_netdev,
+ index_hlist);
+ if (next_dev) {
+ *next = next_dev->idx;
+ return 0;
+ }
+ }
+
+ return -ENOENT;
+}
+
static int bq_xmit_all(struct xdp_bulk_queue *bq, u32 flags,
bool in_napi_ctx)
{
@@ -235,7 +354,7 @@ static int bq_xmit_all(struct xdp_bulk_queue *bq, u32 flags,
out:
bq->count = 0;
- trace_xdp_devmap_xmit(&obj->dtab->map, obj->bit,
+ trace_xdp_devmap_xmit(&obj->dtab->map, obj->idx,
sent, drops, bq->dev_rx, dev, err);
bq->dev_rx = NULL;
__list_del_clearprev(&bq->flush_node);
@@ -363,6 +482,15 @@ static void *dev_map_lookup_elem(struct bpf_map *map, void *key)
return dev ? &dev->ifindex : NULL;
}
+static void *dev_map_hash_lookup_elem(struct bpf_map *map, void *key)
+{
+ struct bpf_dtab_netdev *obj = __dev_map_hash_lookup_elem(map,
+ *(u32 *)key);
+ struct net_device *dev = obj ? obj->dev : NULL;
+
+ return dev ? &dev->ifindex : NULL;
+}
+
static void dev_map_flush_old(struct bpf_dtab_netdev *dev)
{
if (dev->dev->netdev_ops->ndo_xdp_xmit) {
@@ -412,17 +540,74 @@ static int dev_map_delete_elem(struct bpf_map *map, void *key)
return 0;
}
-static int dev_map_update_elem(struct bpf_map *map, void *key, void *value,
- u64 map_flags)
+static int dev_map_hash_delete_elem(struct bpf_map *map, void *key)
{
struct bpf_dtab *dtab = container_of(map, struct bpf_dtab, map);
- struct net *net = current->nsproxy->net_ns;
+ struct bpf_dtab_netdev *old_dev;
+ int k = *(u32 *)key;
+ unsigned long flags;
+ int ret = -ENOENT;
+
+ spin_lock_irqsave(&dtab->index_lock, flags);
+
+ old_dev = __dev_map_hash_lookup_elem(map, k);
+ if (old_dev) {
+ dtab->items--;
+ hlist_del_init_rcu(&old_dev->index_hlist);
+ call_rcu(&old_dev->rcu, __dev_map_entry_free);
+ ret = 0;
+ }
+ spin_unlock_irqrestore(&dtab->index_lock, flags);
+
+ return ret;
+}
+
+static struct bpf_dtab_netdev *__dev_map_alloc_node(struct net *net,
+ struct bpf_dtab *dtab,
+ u32 ifindex,
+ unsigned int idx)
+{
gfp_t gfp = GFP_ATOMIC | __GFP_NOWARN;
+ struct bpf_dtab_netdev *dev;
+ struct xdp_bulk_queue *bq;
+ int cpu;
+
+ dev = kmalloc_node(sizeof(*dev), gfp, dtab->map.numa_node);
+ if (!dev)
+ return ERR_PTR(-ENOMEM);
+
+ dev->bulkq = __alloc_percpu_gfp(sizeof(*dev->bulkq),
+ sizeof(void *), gfp);
+ if (!dev->bulkq) {
+ kfree(dev);
+ return ERR_PTR(-ENOMEM);
+ }
+
+ for_each_possible_cpu(cpu) {
+ bq = per_cpu_ptr(dev->bulkq, cpu);
+ bq->obj = dev;
+ }
+
+ dev->dev = dev_get_by_index(net, ifindex);
+ if (!dev->dev) {
+ free_percpu(dev->bulkq);
+ kfree(dev);
+ return ERR_PTR(-EINVAL);
+ }
+
+ dev->idx = idx;
+ dev->dtab = dtab;
+
+ return dev;
+}
+
+static int __dev_map_update_elem(struct net *net, struct bpf_map *map,
+ void *key, void *value, u64 map_flags)
+{
+ struct bpf_dtab *dtab = container_of(map, struct bpf_dtab, map);
struct bpf_dtab_netdev *dev, *old_dev;
u32 ifindex = *(u32 *)value;
- struct xdp_bulk_queue *bq;
u32 i = *(u32 *)key;
- int cpu;
if (unlikely(map_flags > BPF_EXIST))
return -EINVAL;
@@ -434,31 +619,9 @@ static int dev_map_update_elem(struct bpf_map *map, void *key, void *value,
if (!ifindex) {
dev = NULL;
} else {
- dev = kmalloc_node(sizeof(*dev), gfp, map->numa_node);
- if (!dev)
- return -ENOMEM;
-
- dev->bulkq = __alloc_percpu_gfp(sizeof(*dev->bulkq),
- sizeof(void *), gfp);
- if (!dev->bulkq) {
- kfree(dev);
- return -ENOMEM;
- }
-
- for_each_possible_cpu(cpu) {
- bq = per_cpu_ptr(dev->bulkq, cpu);
- bq->obj = dev;
- }
-
- dev->dev = dev_get_by_index(net, ifindex);
- if (!dev->dev) {
- free_percpu(dev->bulkq);
- kfree(dev);
- return -EINVAL;
- }
-
- dev->bit = i;
- dev->dtab = dtab;
+ dev = __dev_map_alloc_node(net, dtab, ifindex, i);
+ if (IS_ERR(dev))
+ return PTR_ERR(dev);
}
/* Use call_rcu() here to ensure rcu critical sections have completed
@@ -472,6 +635,70 @@ static int dev_map_update_elem(struct bpf_map *map, void *key, void *value,
return 0;
}
+static int dev_map_update_elem(struct bpf_map *map, void *key, void *value,
+ u64 map_flags)
+{
+ return __dev_map_update_elem(current->nsproxy->net_ns,
+ map, key, value, map_flags);
+}
+
+static int __dev_map_hash_update_elem(struct net *net, struct bpf_map *map,
+ void *key, void *value, u64 map_flags)
+{
+ struct bpf_dtab *dtab = container_of(map, struct bpf_dtab, map);
+ struct bpf_dtab_netdev *dev, *old_dev;
+ u32 ifindex = *(u32 *)value;
+ u32 idx = *(u32 *)key;
+ unsigned long flags;
+ int err = -EEXIST;
+
+ if (unlikely(map_flags > BPF_EXIST || !ifindex))
+ return -EINVAL;
+
+ spin_lock_irqsave(&dtab->index_lock, flags);
+
+ old_dev = __dev_map_hash_lookup_elem(map, idx);
+ if (old_dev && (map_flags & BPF_NOEXIST))
+ goto out_err;
+
+ dev = __dev_map_alloc_node(net, dtab, ifindex, idx);
+ if (IS_ERR(dev)) {
+ err = PTR_ERR(dev);
+ goto out_err;
+ }
+
+ if (old_dev) {
+ hlist_del_rcu(&old_dev->index_hlist);
+ } else {
+ if (dtab->items >= dtab->map.max_entries) {
+ spin_unlock_irqrestore(&dtab->index_lock, flags);
+ call_rcu(&dev->rcu, __dev_map_entry_free);
+ return -E2BIG;
+ }
+ dtab->items++;
+ }
+
+ hlist_add_head_rcu(&dev->index_hlist,
+ dev_map_index_hash(dtab, idx));
+ spin_unlock_irqrestore(&dtab->index_lock, flags);
+
+ if (old_dev)
+ call_rcu(&old_dev->rcu, __dev_map_entry_free);
+
+ return 0;
+
+out_err:
+ spin_unlock_irqrestore(&dtab->index_lock, flags);
+ return err;
+}
+
+static int dev_map_hash_update_elem(struct bpf_map *map, void *key, void *value,
+ u64 map_flags)
+{
+ return __dev_map_hash_update_elem(current->nsproxy->net_ns,
+ map, key, value, map_flags);
+}
+
const struct bpf_map_ops dev_map_ops = {
.map_alloc = dev_map_alloc,
.map_free = dev_map_free,
@@ -482,6 +709,16 @@ const struct bpf_map_ops dev_map_ops = {
.map_check_btf = map_check_no_btf,
};
+const struct bpf_map_ops dev_map_hash_ops = {
+ .map_alloc = dev_map_alloc,
+ .map_free = dev_map_free,
+ .map_get_next_key = dev_map_hash_get_next_key,
+ .map_lookup_elem = dev_map_hash_lookup_elem,
+ .map_update_elem = dev_map_hash_update_elem,
+ .map_delete_elem = dev_map_hash_delete_elem,
+ .map_check_btf = map_check_no_btf,
+};
+
static int dev_map_notification(struct notifier_block *notifier,
ulong event, void *ptr)
{