But, for the very least, should we also extend
Documentation/bpf/map_cgroup_storage.rst to cover the new map? We've
tried to keep some of the important details in there..
Signed-off-by: Yonghong Song <yhs@xxxxxx>
---
include/linux/bpf.h | 3 +
include/linux/bpf_types.h | 1 +
include/linux/cgroup-defs.h | 4 +
include/uapi/linux/bpf.h | 39 +++++
kernel/bpf/Makefile | 2 +-
kernel/bpf/bpf_cgroup_storage.c | 280 ++++++++++++++++++++++++++++++++
kernel/bpf/helpers.c | 6 +
kernel/bpf/syscall.c | 3 +-
kernel/bpf/verifier.c | 14 +-
kernel/cgroup/cgroup.c | 4 +
kernel/trace/bpf_trace.c | 4 +
scripts/bpf_doc.py | 2 +
tools/include/uapi/linux/bpf.h | 39 +++++
13 files changed, 398 insertions(+), 3 deletions(-)
create mode 100644 kernel/bpf/bpf_cgroup_storage.c
diff --git a/include/linux/bpf.h b/include/linux/bpf.h
index 9e7d46d16032..1395a01c7f18 100644
--- a/include/linux/bpf.h
+++ b/include/linux/bpf.h
@@ -2045,6 +2045,7 @@ struct bpf_link *bpf_link_by_id(u32 id);
const struct bpf_func_proto *bpf_base_func_proto(enum bpf_func_id
func_id);
void bpf_task_storage_free(struct task_struct *task);
+void bpf_local_cgroup_storage_free(struct cgroup *cgroup);
bool bpf_prog_has_kfunc_call(const struct bpf_prog *prog);
const struct btf_func_model *
bpf_jit_find_kfunc_model(const struct bpf_prog *prog,
@@ -2537,6 +2538,8 @@ extern const struct bpf_func_proto
bpf_copy_from_user_task_proto;
extern const struct bpf_func_proto bpf_set_retval_proto;
extern const struct bpf_func_proto bpf_get_retval_proto;
extern const struct bpf_func_proto bpf_user_ringbuf_drain_proto;
+extern const struct bpf_func_proto bpf_cgroup_storage_get_proto;
+extern const struct bpf_func_proto bpf_cgroup_storage_delete_proto;
const struct bpf_func_proto *tracing_prog_func_proto(
enum bpf_func_id func_id, const struct bpf_prog *prog);
diff --git a/include/linux/bpf_types.h b/include/linux/bpf_types.h
index 2c6a4f2562a7..7a0362d7a0aa 100644
--- a/include/linux/bpf_types.h
+++ b/include/linux/bpf_types.h
@@ -90,6 +90,7 @@ BPF_MAP_TYPE(BPF_MAP_TYPE_CGROUP_ARRAY,
cgroup_array_map_ops)
#ifdef CONFIG_CGROUP_BPF
BPF_MAP_TYPE(BPF_MAP_TYPE_CGROUP_STORAGE, cgroup_storage_map_ops)
BPF_MAP_TYPE(BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE,
cgroup_storage_map_ops)
+BPF_MAP_TYPE(BPF_MAP_TYPE_CGROUP_LOCAL_STORAGE,
cgroup_local_storage_map_ops)
#endif
BPF_MAP_TYPE(BPF_MAP_TYPE_HASH, htab_map_ops)
BPF_MAP_TYPE(BPF_MAP_TYPE_PERCPU_HASH, htab_percpu_map_ops)
diff --git a/include/linux/cgroup-defs.h b/include/linux/cgroup-defs.h
index 4bcf56b3491c..c6f4590dda68 100644
--- a/include/linux/cgroup-defs.h
+++ b/include/linux/cgroup-defs.h
@@ -504,6 +504,10 @@ struct cgroup {
/* Used to store internal freezer state */
struct cgroup_freezer_state freezer;
+#ifdef CONFIG_BPF_SYSCALL
+ struct bpf_local_storage __rcu *bpf_cgroup_storage;
+#endif
+
/* ids of the ancestors at each level including self */
u64 ancestor_ids[];
};
diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h
index 17f61338f8f8..d918b4054297 100644
--- a/include/uapi/linux/bpf.h
+++ b/include/uapi/linux/bpf.h
@@ -935,6 +935,7 @@ enum bpf_map_type {
BPF_MAP_TYPE_TASK_STORAGE,
BPF_MAP_TYPE_BLOOM_FILTER,
BPF_MAP_TYPE_USER_RINGBUF,
+ BPF_MAP_TYPE_CGROUP_LOCAL_STORAGE,
};
/* Note that tracing related programs such as
@@ -5435,6 +5436,42 @@ union bpf_attr {
* **-E2BIG** if user-space has tried to publish a sample
which is
* larger than the size of the ring buffer, or which cannot fit
* within a struct bpf_dynptr.
+ *
+ * void *bpf_cgroup_local_storage_get(struct bpf_map *map, struct
cgroup *cgroup, void *value, u64 flags)
+ * Description
+ * Get a bpf_local_storage from the *cgroup*.
+ *
+ * Logically, it could be thought of as getting the value from
+ * a *map* with *cgroup* as the **key**. From this
+ * perspective, the usage is not much different from
+ * **bpf_map_lookup_elem**\ (*map*, **&**\ *cgroup*) except this
+ * helper enforces the key must be a cgroup struct and the map
must also
+ * be a **BPF_MAP_TYPE_CGROUP_LOCAL_STORAGE**.
+ *
+ * Underneath, the value is stored locally at *cgroup* instead of
+ * the *map*. The *map* is used as the bpf-local-storage
+ * "type". The bpf-local-storage "type" (i.e. the *map*) is
+ * searched against all bpf_local_storage residing at *cgroup*.
+ *
+ * An optional *flags* (**BPF_LOCAL_STORAGE_GET_F_CREATE**)
can be
+ * used such that a new bpf_local_storage will be
+ * created if one does not exist. *value* can be used
+ * together with **BPF_LOCAL_STORAGE_GET_F_CREATE** to specify
+ * the initial value of a bpf_local_storage. If *value* is
+ * **NULL**, the new bpf_local_storage will be zero initialized.
+ * Return
+ * A bpf_local_storage pointer is returned on success.
+ *
+ * **NULL** if not found or there was an error in adding
+ * a new bpf_local_storage.
+ *
+ * long bpf_cgroup_local_storage_delete(struct bpf_map *map, struct
cgroup *cgroup)
+ * Description
+ * Delete a bpf_local_storage from a *cgroup*.
+ * Return
+ * 0 on success.
+ *
+ * **-ENOENT** if the bpf_local_storage cannot be found.
*/
#define ___BPF_FUNC_MAPPER(FN, ctx...) \
FN(unspec, 0, ##ctx) \
@@ -5647,6 +5684,8 @@ union bpf_attr {
FN(tcp_raw_check_syncookie_ipv6, 207, ##ctx) \
FN(ktime_get_tai_ns, 208, ##ctx) \
FN(user_ringbuf_drain, 209, ##ctx) \
+ FN(cgroup_local_storage_get, 210, ##ctx) \
+ FN(cgroup_local_storage_delete, 211, ##ctx) \
/* */
/* backwards-compatibility macros for users of __BPF_FUNC_MAPPER
that don't
diff --git a/kernel/bpf/Makefile b/kernel/bpf/Makefile
index 341c94f208f4..b02693f51978 100644
--- a/kernel/bpf/Makefile
+++ b/kernel/bpf/Makefile
@@ -25,7 +25,7 @@ ifeq ($(CONFIG_PERF_EVENTS),y)
obj-$(CONFIG_BPF_SYSCALL) += stackmap.o
endif
ifeq ($(CONFIG_CGROUPS),y)
-obj-$(CONFIG_BPF_SYSCALL) += cgroup_iter.o
+obj-$(CONFIG_BPF_SYSCALL) += cgroup_iter.o bpf_cgroup_storage.o
endif
obj-$(CONFIG_CGROUP_BPF) += cgroup.o
ifeq ($(CONFIG_INET),y)
diff --git a/kernel/bpf/bpf_cgroup_storage.c
b/kernel/bpf/bpf_cgroup_storage.c
new file mode 100644
index 000000000000..9974784822da
--- /dev/null
+++ b/kernel/bpf/bpf_cgroup_storage.c
@@ -0,0 +1,280 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2022 Meta Platforms, Inc. and affiliates.
+ */
+
+#include <linux/types.h>
+#include <linux/bpf.h>
+#include <linux/bpf_local_storage.h>
+#include <uapi/linux/btf.h>
+#include <linux/btf_ids.h>
+
+DEFINE_BPF_STORAGE_CACHE(cgroup_cache);
+
+static DEFINE_PER_CPU(int, bpf_cgroup_storage_busy);
+
+static void bpf_cgroup_storage_lock(void)
+{
+ migrate_disable();
+ this_cpu_inc(bpf_cgroup_storage_busy);
+}
+
+static void bpf_cgroup_storage_unlock(void)
+{
+ this_cpu_dec(bpf_cgroup_storage_busy);
+ migrate_enable();
+}
+
+static bool bpf_cgroup_storage_trylock(void)
+{
+ migrate_disable();
+ if (unlikely(this_cpu_inc_return(bpf_cgroup_storage_busy) != 1)) {
+ this_cpu_dec(bpf_cgroup_storage_busy);
+ migrate_enable();
+ return false;
+ }
+ return true;
+}
Task storage has lock/unlock/trylock; inode storage doesn't; why does
cgroup need it as well?
+static struct bpf_local_storage __rcu **cgroup_storage_ptr(void *owner)
+{
+ struct cgroup *cg = owner;
+
+ return &cg->bpf_cgroup_storage;
+}
+
+void bpf_local_cgroup_storage_free(struct cgroup *cgroup)
+{
+ struct bpf_local_storage *local_storage;
+ struct bpf_local_storage_elem *selem;
+ bool free_cgroup_storage = false;
+ struct hlist_node *n;
+ unsigned long flags;
+
+ rcu_read_lock();
+ local_storage = rcu_dereference(cgroup->bpf_cgroup_storage);
+ if (!local_storage) {
+ rcu_read_unlock();
+ return;
+ }
+
+ /* Neither the bpf_prog nor the bpf-map's syscall
+ * could be modifying the local_storage->list now.
+ * Thus, no elem can be added-to or deleted-from the
+ * local_storage->list by the bpf_prog or by the bpf-map's syscall.
+ *
+ * It is racing with bpf_local_storage_map_free() alone
+ * when unlinking elem from the local_storage->list and
+ * the map's bucket->list.
+ */
+ bpf_cgroup_storage_lock();
+ raw_spin_lock_irqsave(&local_storage->lock, flags);
+ hlist_for_each_entry_safe(selem, n, &local_storage->list, snode) {
+ bpf_selem_unlink_map(selem);
+ free_cgroup_storage =
+ bpf_selem_unlink_storage_nolock(local_storage, selem,
false, false);
+ }
+ raw_spin_unlock_irqrestore(&local_storage->lock, flags);
+ bpf_cgroup_storage_unlock();
+ rcu_read_unlock();
+
+ /* free_cgroup_storage should always be true as long as
+ * local_storage->list was non-empty.
+ */
+ if (free_cgroup_storage)
+ kfree_rcu(local_storage, rcu);
+}
+static struct bpf_local_storage_data *
+cgroup_storage_lookup(struct cgroup *cgroup, struct bpf_map *map,
bool cacheit_lockit)
+{
+ struct bpf_local_storage *cgroup_storage;
+ struct bpf_local_storage_map *smap;
+
+ cgroup_storage = rcu_dereference_check(cgroup->bpf_cgroup_storage,
+ bpf_rcu_lock_held());
+ if (!cgroup_storage)
+ return NULL;
+
+ smap = (struct bpf_local_storage_map *)map;
+ return bpf_local_storage_lookup(cgroup_storage, smap,
cacheit_lockit);
+}
+
+static void *bpf_cgroup_storage_lookup_elem(struct bpf_map *map, void
*key)
+{
+ struct bpf_local_storage_data *sdata;
+ struct cgroup *cgroup;
+ int fd;
+
+ fd = *(int *)key;
+ cgroup = cgroup_get_from_fd(fd);
+ if (IS_ERR(cgroup))
+ return ERR_CAST(cgroup);
+
+ bpf_cgroup_storage_lock();
+ sdata = cgroup_storage_lookup(cgroup, map, true);
+ bpf_cgroup_storage_unlock();
+ cgroup_put(cgroup);
+ return sdata ? sdata->data : NULL;
+}
A lot of the above (free/lookup) seems to be copy-pasted from the task
storage;
any point in trying to generalize the common parts?
+static int bpf_cgroup_storage_update_elem(struct bpf_map *map, void
*key,
+ void *value, u64 map_flags)
+{
+ struct bpf_local_storage_data *sdata;
+ struct cgroup *cgroup;
+ int err, fd;
+
+ fd = *(int *)key;
+ cgroup = cgroup_get_from_fd(fd);
+ if (IS_ERR(cgroup))
+ return PTR_ERR(cgroup);
+
+ bpf_cgroup_storage_lock();
+ sdata = bpf_local_storage_update(cgroup, (struct
bpf_local_storage_map *)map,
+ value, map_flags, GFP_ATOMIC);
+ bpf_cgroup_storage_unlock();
+ err = PTR_ERR_OR_ZERO(sdata);
+ cgroup_put(cgroup);
+ return err;
+}
+
+static int cgroup_storage_delete(struct cgroup *cgroup, struct
bpf_map *map)
+{
+ struct bpf_local_storage_data *sdata;
+
+ sdata = cgroup_storage_lookup(cgroup, map, false);
+ if (!sdata)
+ return -ENOENT;
+
+ bpf_selem_unlink(SELEM(sdata), true);
+ return 0;
+}
+
+static int bpf_cgroup_storage_delete_elem(struct bpf_map *map, void
*key)
+{
+ struct cgroup *cgroup;
+ int err, fd;
+
+ fd = *(int *)key;
+ cgroup = cgroup_get_from_fd(fd);
+ if (IS_ERR(cgroup))
+ return PTR_ERR(cgroup);
+
+ bpf_cgroup_storage_lock();
+ err = cgroup_storage_delete(cgroup, map);
+ bpf_cgroup_storage_unlock();
+ if (err)
+ return err;
+
+ cgroup_put(cgroup);
+ return 0;
+}
+
+static int notsupp_get_next_key(struct bpf_map *map, void *key, void
*next_key)
+{
+ return -ENOTSUPP;
+}
+
+static struct bpf_map *cgroup_storage_map_alloc(union bpf_attr *attr)
+{
+ struct bpf_local_storage_map *smap;
+
+ smap = bpf_local_storage_map_alloc(attr);
+ if (IS_ERR(smap))
+ return ERR_CAST(smap);
+
+ smap->cache_idx = bpf_local_storage_cache_idx_get(&cgroup_cache);
+ return &smap->map;
+}
+
+static void cgroup_storage_map_free(struct bpf_map *map)
+{
+ struct bpf_local_storage_map *smap;
+
+ smap = (struct bpf_local_storage_map *)map;
+ bpf_local_storage_cache_idx_free(&cgroup_cache, smap->cache_idx);
+ bpf_local_storage_map_free(smap, NULL);
+}
+
+/* *gfp_flags* is a hidden argument provided by the verifier */
+BPF_CALL_5(bpf_cgroup_storage_get, struct bpf_map *, map, struct
cgroup *, cgroup,
+ void *, value, u64, flags, gfp_t, gfp_flags)
+{
+ struct bpf_local_storage_data *sdata;
+
+ WARN_ON_ONCE(!bpf_rcu_lock_held());
+ if (flags & ~(BPF_LOCAL_STORAGE_GET_F_CREATE))
+ return (unsigned long)NULL;
+
+ if (!cgroup)
+ return (unsigned long)NULL;
+
+ if (!bpf_cgroup_storage_trylock())
+ return (unsigned long)NULL;
+
+ sdata = cgroup_storage_lookup(cgroup, map, true);
+ if (sdata)
+ goto unlock;
+
+ /* only allocate new storage, when the cgroup is refcounted */
+ if (!percpu_ref_is_dying(&cgroup->self.refcnt) &&
+ (flags & BPF_LOCAL_STORAGE_GET_F_CREATE))
+ sdata = bpf_local_storage_update(cgroup, (struct
bpf_local_storage_map *)map,
+ value, BPF_NOEXIST, gfp_flags);
+
+unlock:
+ bpf_cgroup_storage_unlock();
+ return IS_ERR_OR_NULL(sdata) ? (unsigned long)NULL : (unsigned
long)sdata->data;
+}
+
+BPF_CALL_2(bpf_cgroup_storage_delete, struct bpf_map *, map, struct
cgroup *, cgroup)
+{
+ int ret;
+
+ WARN_ON_ONCE(!bpf_rcu_lock_held());
+ if (!cgroup)
+ return -EINVAL;
+
+ if (!bpf_cgroup_storage_trylock())
+ return -EBUSY;
+
+ ret = cgroup_storage_delete(cgroup, map);
+ bpf_cgroup_storage_unlock();
+ return ret;
+}
+
+BTF_ID_LIST_SINGLE(cgroup_storage_map_btf_ids, struct,
bpf_local_storage_map)
+const struct bpf_map_ops cgroup_local_storage_map_ops = {
+ .map_meta_equal = bpf_map_meta_equal,
+ .map_alloc_check = bpf_local_storage_map_alloc_check,
+ .map_alloc = cgroup_storage_map_alloc,
+ .map_free = cgroup_storage_map_free,
+ .map_get_next_key = notsupp_get_next_key,
+ .map_lookup_elem = bpf_cgroup_storage_lookup_elem,
+ .map_update_elem = bpf_cgroup_storage_update_elem,
+ .map_delete_elem = bpf_cgroup_storage_delete_elem,
+ .map_check_btf = bpf_local_storage_map_check_btf,
+ .map_btf_id = &cgroup_storage_map_btf_ids[0],
+ .map_owner_storage_ptr = cgroup_storage_ptr,
+};
+
+const struct bpf_func_proto bpf_cgroup_storage_get_proto = {
+ .func = bpf_cgroup_storage_get,
+ .gpl_only = false,
+ .ret_type = RET_PTR_TO_MAP_VALUE_OR_NULL,
+ .arg1_type = ARG_CONST_MAP_PTR,
+ .arg2_type = ARG_PTR_TO_BTF_ID,
+ .arg2_btf_id = &bpf_cgroup_btf_id[0],
+ .arg3_type = ARG_PTR_TO_MAP_VALUE_OR_NULL,
+ .arg4_type = ARG_ANYTHING,
+};
+
+const struct bpf_func_proto bpf_cgroup_storage_delete_proto = {
+ .func = bpf_cgroup_storage_delete,
+ .gpl_only = false,
+ .ret_type = RET_INTEGER,
+ .arg1_type = ARG_CONST_MAP_PTR,
+ .arg2_type = ARG_PTR_TO_BTF_ID,
+ .arg2_btf_id = &bpf_cgroup_btf_id[0],
+};
diff --git a/kernel/bpf/helpers.c b/kernel/bpf/helpers.c
index a6b04faed282..5c5bb08832ec 100644
--- a/kernel/bpf/helpers.c
+++ b/kernel/bpf/helpers.c
@@ -1663,6 +1663,12 @@ bpf_base_func_proto(enum bpf_func_id func_id)
return &bpf_dynptr_write_proto;
case BPF_FUNC_dynptr_data:
return &bpf_dynptr_data_proto;
+#ifdef CONFIG_CGROUPS
+ case BPF_FUNC_cgroup_local_storage_get:
+ return &bpf_cgroup_storage_get_proto;
+ case BPF_FUNC_cgroup_local_storage_delete:
+ return &bpf_cgroup_storage_delete_proto;
+#endif
default:
break;
}
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index 7b373a5e861f..e53c7fae6e22 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -1016,7 +1016,8 @@ static int map_check_btf(struct bpf_map *map,
const struct btf *btf,
map->map_type != BPF_MAP_TYPE_CGROUP_STORAGE &&
map->map_type != BPF_MAP_TYPE_SK_STORAGE &&
map->map_type != BPF_MAP_TYPE_INODE_STORAGE &&
- map->map_type != BPF_MAP_TYPE_TASK_STORAGE)
+ map->map_type != BPF_MAP_TYPE_TASK_STORAGE &&
+ map->map_type != BPF_MAP_TYPE_CGROUP_LOCAL_STORAGE)
return -ENOTSUPP;
if (map->spin_lock_off + sizeof(struct bpf_spin_lock) >
map->value_size) {
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index 6f6d2d511c06..f36f6a3c0d50 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -6360,6 +6360,11 @@ static int check_map_func_compatibility(struct
bpf_verifier_env *env,
func_id != BPF_FUNC_task_storage_delete)
goto error;
break;
+ case BPF_MAP_TYPE_CGROUP_LOCAL_STORAGE:
+ if (func_id != BPF_FUNC_cgroup_local_storage_get &&
+ func_id != BPF_FUNC_cgroup_local_storage_delete)
+ goto error;
+ break;
case BPF_MAP_TYPE_BLOOM_FILTER:
if (func_id != BPF_FUNC_map_peek_elem &&
func_id != BPF_FUNC_map_push_elem)
@@ -6472,6 +6477,11 @@ static int check_map_func_compatibility(struct
bpf_verifier_env *env,
if (map->map_type != BPF_MAP_TYPE_TASK_STORAGE)
goto error;
break;
+ case BPF_FUNC_cgroup_local_storage_get:
+ case BPF_FUNC_cgroup_local_storage_delete:
+ if (map->map_type != BPF_MAP_TYPE_CGROUP_LOCAL_STORAGE)
+ goto error;
+ break;
default:
break;
}
@@ -12713,6 +12723,7 @@ static int check_map_prog_compatibility(struct
bpf_verifier_env *env,
case BPF_MAP_TYPE_INODE_STORAGE:
case BPF_MAP_TYPE_SK_STORAGE:
case BPF_MAP_TYPE_TASK_STORAGE:
+ case BPF_MAP_TYPE_CGROUP_LOCAL_STORAGE:
break;
default:
verbose(env,
@@ -14149,7 +14160,8 @@ static int do_misc_fixups(struct
bpf_verifier_env *env)
if (insn->imm == BPF_FUNC_task_storage_get ||
insn->imm == BPF_FUNC_sk_storage_get ||
- insn->imm == BPF_FUNC_inode_storage_get) {
+ insn->imm == BPF_FUNC_inode_storage_get ||
+ insn->imm == BPF_FUNC_cgroup_local_storage_get) {
if (env->prog->aux->sleepable)
insn_buf[0] = BPF_MOV64_IMM(BPF_REG_5, (__force
__s32)GFP_KERNEL);
else
diff --git a/kernel/cgroup/cgroup.c b/kernel/cgroup/cgroup.c
index 8ad2c267ff47..2fa2c950c7fb 100644
--- a/kernel/cgroup/cgroup.c
+++ b/kernel/cgroup/cgroup.c
@@ -985,6 +985,10 @@ void put_css_set_locked(struct css_set *cset)
put_css_set_locked(cset->dom_cset);
}
+#ifdef CONFIG_BPF_SYSCALL
+ bpf_local_cgroup_storage_free(cset->dfl_cgrp);
+#endif
+
kfree_rcu(cset, rcu_head);
}
diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c
index 688552df95ca..179adaae4a9f 100644
--- a/kernel/trace/bpf_trace.c
+++ b/kernel/trace/bpf_trace.c
@@ -1454,6 +1454,10 @@ bpf_tracing_func_proto(enum bpf_func_id
func_id, const struct bpf_prog *prog)
return &bpf_get_current_cgroup_id_proto;
case BPF_FUNC_get_current_ancestor_cgroup_id:
return &bpf_get_current_ancestor_cgroup_id_proto;
+ case BPF_FUNC_cgroup_local_storage_get:
+ return &bpf_cgroup_storage_get_proto;
+ case BPF_FUNC_cgroup_local_storage_delete:
+ return &bpf_cgroup_storage_delete_proto;
#endif
case BPF_FUNC_send_signal:
return &bpf_send_signal_proto;
diff --git a/scripts/bpf_doc.py b/scripts/bpf_doc.py
index c0e6690be82a..fdb0aff8cb5a 100755
--- a/scripts/bpf_doc.py
+++ b/scripts/bpf_doc.py
@@ -685,6 +685,7 @@ class PrinterHelpers(Printer):
'struct udp6_sock',
'struct unix_sock',
'struct task_struct',
+ 'struct cgroup',
'struct __sk_buff',
'struct sk_msg_md',
@@ -742,6 +743,7 @@ class PrinterHelpers(Printer):
'struct udp6_sock',
'struct unix_sock',
'struct task_struct',
+ 'struct cgroup',
'struct path',
'struct btf_ptr',
'struct inode',
diff --git a/tools/include/uapi/linux/bpf.h
b/tools/include/uapi/linux/bpf.h
index 17f61338f8f8..d918b4054297 100644
--- a/tools/include/uapi/linux/bpf.h
+++ b/tools/include/uapi/linux/bpf.h
@@ -935,6 +935,7 @@ enum bpf_map_type {
BPF_MAP_TYPE_TASK_STORAGE,
BPF_MAP_TYPE_BLOOM_FILTER,
BPF_MAP_TYPE_USER_RINGBUF,
+ BPF_MAP_TYPE_CGROUP_LOCAL_STORAGE,
};
/* Note that tracing related programs such as
@@ -5435,6 +5436,42 @@ union bpf_attr {
* **-E2BIG** if user-space has tried to publish a sample
which is
* larger than the size of the ring buffer, or which cannot fit
* within a struct bpf_dynptr.
+ *
+ * void *bpf_cgroup_local_storage_get(struct bpf_map *map, struct
cgroup *cgroup, void *value, u64 flags)
+ * Description
+ * Get a bpf_local_storage from the *cgroup*.
+ *
+ * Logically, it could be thought of as getting the value from
+ * a *map* with *cgroup* as the **key**. From this
+ * perspective, the usage is not much different from
+ * **bpf_map_lookup_elem**\ (*map*, **&**\ *cgroup*) except this
+ * helper enforces the key must be a cgroup struct and the map
must also
+ * be a **BPF_MAP_TYPE_CGROUP_LOCAL_STORAGE**.
+ *
+ * Underneath, the value is stored locally at *cgroup* instead of
+ * the *map*. The *map* is used as the bpf-local-storage
+ * "type". The bpf-local-storage "type" (i.e. the *map*) is
+ * searched against all bpf_local_storage residing at *cgroup*.
+ *
+ * An optional *flags* (**BPF_LOCAL_STORAGE_GET_F_CREATE**)
can be
+ * used such that a new bpf_local_storage will be
+ * created if one does not exist. *value* can be used
+ * together with **BPF_LOCAL_STORAGE_GET_F_CREATE** to specify
+ * the initial value of a bpf_local_storage. If *value* is
+ * **NULL**, the new bpf_local_storage will be zero initialized.
+ * Return
+ * A bpf_local_storage pointer is returned on success.
+ *
+ * **NULL** if not found or there was an error in adding
+ * a new bpf_local_storage.
+ *
+ * long bpf_cgroup_local_storage_delete(struct bpf_map *map, struct
cgroup *cgroup)
+ * Description
+ * Delete a bpf_local_storage from a *cgroup*.
+ * Return
+ * 0 on success.
+ *
+ * **-ENOENT** if the bpf_local_storage cannot be found.
*/
#define ___BPF_FUNC_MAPPER(FN, ctx...) \
FN(unspec, 0, ##ctx) \
@@ -5647,6 +5684,8 @@ union bpf_attr {
FN(tcp_raw_check_syncookie_ipv6, 207, ##ctx) \
FN(ktime_get_tai_ns, 208, ##ctx) \
FN(user_ringbuf_drain, 209, ##ctx) \
+ FN(cgroup_local_storage_get, 210, ##ctx) \
+ FN(cgroup_local_storage_delete, 211, ##ctx) \
/* */
/* backwards-compatibility macros for users of __BPF_FUNC_MAPPER
that don't
--
2.30.2
