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-rw-r--r--kernel/bpf/Makefile2
-rw-r--r--kernel/bpf/arraymap.c38
-rw-r--r--kernel/bpf/bpf_insn_array.c304
-rw-r--r--kernel/bpf/bpf_local_storage.c235
-rw-r--r--kernel/bpf/bpf_lsm.c1
-rw-r--r--kernel/bpf/core.c26
-rw-r--r--kernel/bpf/disasm.c3
-rw-r--r--kernel/bpf/hashtab.c67
-rw-r--r--kernel/bpf/helpers.c296
-rw-r--r--kernel/bpf/liveness.c42
-rw-r--r--kernel/bpf/log.c3
-rw-r--r--kernel/bpf/range_tree.c21
-rw-r--r--kernel/bpf/ringbuf.c114
-rw-r--r--kernel/bpf/rqspinlock.c90
-rw-r--r--kernel/bpf/stackmap.c62
-rw-r--r--kernel/bpf/stream.c159
-rw-r--r--kernel/bpf/syscall.c86
-rw-r--r--kernel/bpf/trampoline.c83
-rw-r--r--kernel/bpf/verifier.c983
19 files changed, 1819 insertions, 796 deletions
diff --git a/kernel/bpf/Makefile b/kernel/bpf/Makefile
index 7fd0badfacb1..232cbc97434d 100644
--- a/kernel/bpf/Makefile
+++ b/kernel/bpf/Makefile
@@ -9,7 +9,7 @@ CFLAGS_core.o += -Wno-override-init $(cflags-nogcse-yy)
obj-$(CONFIG_BPF_SYSCALL) += syscall.o verifier.o inode.o helpers.o tnum.o log.o token.o liveness.o
obj-$(CONFIG_BPF_SYSCALL) += bpf_iter.o map_iter.o task_iter.o prog_iter.o link_iter.o
obj-$(CONFIG_BPF_SYSCALL) += hashtab.o arraymap.o percpu_freelist.o bpf_lru_list.o lpm_trie.o map_in_map.o bloom_filter.o
-obj-$(CONFIG_BPF_SYSCALL) += local_storage.o queue_stack_maps.o ringbuf.o
+obj-$(CONFIG_BPF_SYSCALL) += local_storage.o queue_stack_maps.o ringbuf.o bpf_insn_array.o
obj-$(CONFIG_BPF_SYSCALL) += bpf_local_storage.o bpf_task_storage.o
obj-${CONFIG_BPF_LSM} += bpf_inode_storage.o
obj-$(CONFIG_BPF_SYSCALL) += disasm.o mprog.o
diff --git a/kernel/bpf/arraymap.c b/kernel/bpf/arraymap.c
index 80b1765a3159..1eeb31c5b317 100644
--- a/kernel/bpf/arraymap.c
+++ b/kernel/bpf/arraymap.c
@@ -335,18 +335,17 @@ int bpf_percpu_array_copy(struct bpf_map *map, void *key, void *value)
}
/* Called from syscall */
-static int array_map_get_next_key(struct bpf_map *map, void *key, void *next_key)
+int bpf_array_get_next_key(struct bpf_map *map, void *key, void *next_key)
{
- struct bpf_array *array = container_of(map, struct bpf_array, map);
u32 index = key ? *(u32 *)key : U32_MAX;
u32 *next = (u32 *)next_key;
- if (index >= array->map.max_entries) {
+ if (index >= map->max_entries) {
*next = 0;
return 0;
}
- if (index == array->map.max_entries - 1)
+ if (index == map->max_entries - 1)
return -ENOENT;
*next = index + 1;
@@ -448,19 +447,12 @@ static void array_map_free_internal_structs(struct bpf_map *map)
struct bpf_array *array = container_of(map, struct bpf_array, map);
int i;
- /* We don't reset or free fields other than timer and workqueue
- * on uref dropping to zero.
- */
- if (btf_record_has_field(map->record, BPF_TIMER | BPF_WORKQUEUE | BPF_TASK_WORK)) {
- for (i = 0; i < array->map.max_entries; i++) {
- if (btf_record_has_field(map->record, BPF_TIMER))
- bpf_obj_free_timer(map->record, array_map_elem_ptr(array, i));
- if (btf_record_has_field(map->record, BPF_WORKQUEUE))
- bpf_obj_free_workqueue(map->record, array_map_elem_ptr(array, i));
- if (btf_record_has_field(map->record, BPF_TASK_WORK))
- bpf_obj_free_task_work(map->record, array_map_elem_ptr(array, i));
- }
- }
+ /* We only free internal structs on uref dropping to zero */
+ if (!bpf_map_has_internal_structs(map))
+ return;
+
+ for (i = 0; i < array->map.max_entries; i++)
+ bpf_map_free_internal_structs(map, array_map_elem_ptr(array, i));
}
/* Called when map->refcnt goes to zero, either from workqueue or from syscall */
@@ -796,7 +788,7 @@ const struct bpf_map_ops array_map_ops = {
.map_alloc_check = array_map_alloc_check,
.map_alloc = array_map_alloc,
.map_free = array_map_free,
- .map_get_next_key = array_map_get_next_key,
+ .map_get_next_key = bpf_array_get_next_key,
.map_release_uref = array_map_free_internal_structs,
.map_lookup_elem = array_map_lookup_elem,
.map_update_elem = array_map_update_elem,
@@ -822,7 +814,7 @@ const struct bpf_map_ops percpu_array_map_ops = {
.map_alloc_check = array_map_alloc_check,
.map_alloc = array_map_alloc,
.map_free = array_map_free,
- .map_get_next_key = array_map_get_next_key,
+ .map_get_next_key = bpf_array_get_next_key,
.map_lookup_elem = percpu_array_map_lookup_elem,
.map_gen_lookup = percpu_array_map_gen_lookup,
.map_update_elem = array_map_update_elem,
@@ -1211,7 +1203,7 @@ const struct bpf_map_ops prog_array_map_ops = {
.map_poke_track = prog_array_map_poke_track,
.map_poke_untrack = prog_array_map_poke_untrack,
.map_poke_run = prog_array_map_poke_run,
- .map_get_next_key = array_map_get_next_key,
+ .map_get_next_key = bpf_array_get_next_key,
.map_lookup_elem = fd_array_map_lookup_elem,
.map_delete_elem = fd_array_map_delete_elem,
.map_fd_get_ptr = prog_fd_array_get_ptr,
@@ -1315,7 +1307,7 @@ const struct bpf_map_ops perf_event_array_map_ops = {
.map_alloc_check = fd_array_map_alloc_check,
.map_alloc = array_map_alloc,
.map_free = perf_event_fd_array_map_free,
- .map_get_next_key = array_map_get_next_key,
+ .map_get_next_key = bpf_array_get_next_key,
.map_lookup_elem = fd_array_map_lookup_elem,
.map_delete_elem = fd_array_map_delete_elem,
.map_fd_get_ptr = perf_event_fd_array_get_ptr,
@@ -1351,7 +1343,7 @@ const struct bpf_map_ops cgroup_array_map_ops = {
.map_alloc_check = fd_array_map_alloc_check,
.map_alloc = array_map_alloc,
.map_free = cgroup_fd_array_free,
- .map_get_next_key = array_map_get_next_key,
+ .map_get_next_key = bpf_array_get_next_key,
.map_lookup_elem = fd_array_map_lookup_elem,
.map_delete_elem = fd_array_map_delete_elem,
.map_fd_get_ptr = cgroup_fd_array_get_ptr,
@@ -1436,7 +1428,7 @@ const struct bpf_map_ops array_of_maps_map_ops = {
.map_alloc_check = fd_array_map_alloc_check,
.map_alloc = array_of_map_alloc,
.map_free = array_of_map_free,
- .map_get_next_key = array_map_get_next_key,
+ .map_get_next_key = bpf_array_get_next_key,
.map_lookup_elem = array_of_map_lookup_elem,
.map_delete_elem = fd_array_map_delete_elem,
.map_fd_get_ptr = bpf_map_fd_get_ptr,
diff --git a/kernel/bpf/bpf_insn_array.c b/kernel/bpf/bpf_insn_array.c
new file mode 100644
index 000000000000..c96630cb75bf
--- /dev/null
+++ b/kernel/bpf/bpf_insn_array.c
@@ -0,0 +1,304 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/* Copyright (c) 2025 Isovalent */
+
+#include <linux/bpf.h>
+
+struct bpf_insn_array {
+ struct bpf_map map;
+ atomic_t used;
+ long *ips;
+ DECLARE_FLEX_ARRAY(struct bpf_insn_array_value, values);
+};
+
+#define cast_insn_array(MAP_PTR) \
+ container_of((MAP_PTR), struct bpf_insn_array, map)
+
+#define INSN_DELETED ((u32)-1)
+
+static inline u64 insn_array_alloc_size(u32 max_entries)
+{
+ const u64 base_size = sizeof(struct bpf_insn_array);
+ const u64 entry_size = sizeof(struct bpf_insn_array_value);
+
+ return base_size + max_entries * (entry_size + sizeof(long));
+}
+
+static int insn_array_alloc_check(union bpf_attr *attr)
+{
+ u32 value_size = sizeof(struct bpf_insn_array_value);
+
+ if (attr->max_entries == 0 || attr->key_size != 4 ||
+ attr->value_size != value_size || attr->map_flags != 0)
+ return -EINVAL;
+
+ return 0;
+}
+
+static void insn_array_free(struct bpf_map *map)
+{
+ struct bpf_insn_array *insn_array = cast_insn_array(map);
+
+ bpf_map_area_free(insn_array);
+}
+
+static struct bpf_map *insn_array_alloc(union bpf_attr *attr)
+{
+ u64 size = insn_array_alloc_size(attr->max_entries);
+ struct bpf_insn_array *insn_array;
+
+ insn_array = bpf_map_area_alloc(size, NUMA_NO_NODE);
+ if (!insn_array)
+ return ERR_PTR(-ENOMEM);
+
+ /* ips are allocated right after the insn_array->values[] array */
+ insn_array->ips = (void *)&insn_array->values[attr->max_entries];
+
+ bpf_map_init_from_attr(&insn_array->map, attr);
+
+ /* BPF programs aren't allowed to write to the map */
+ insn_array->map.map_flags |= BPF_F_RDONLY_PROG;
+
+ return &insn_array->map;
+}
+
+static void *insn_array_lookup_elem(struct bpf_map *map, void *key)
+{
+ struct bpf_insn_array *insn_array = cast_insn_array(map);
+ u32 index = *(u32 *)key;
+
+ if (unlikely(index >= insn_array->map.max_entries))
+ return NULL;
+
+ return &insn_array->values[index];
+}
+
+static long insn_array_update_elem(struct bpf_map *map, void *key, void *value, u64 map_flags)
+{
+ struct bpf_insn_array *insn_array = cast_insn_array(map);
+ u32 index = *(u32 *)key;
+ struct bpf_insn_array_value val = {};
+
+ if (unlikely(index >= insn_array->map.max_entries))
+ return -E2BIG;
+
+ if (unlikely(map_flags & BPF_NOEXIST))
+ return -EEXIST;
+
+ copy_map_value(map, &val, value);
+ if (val.jitted_off || val.xlated_off)
+ return -EINVAL;
+
+ insn_array->values[index].orig_off = val.orig_off;
+
+ return 0;
+}
+
+static long insn_array_delete_elem(struct bpf_map *map, void *key)
+{
+ return -EINVAL;
+}
+
+static int insn_array_check_btf(const struct bpf_map *map,
+ const struct btf *btf,
+ const struct btf_type *key_type,
+ const struct btf_type *value_type)
+{
+ if (!btf_type_is_i32(key_type))
+ return -EINVAL;
+
+ if (!btf_type_is_i64(value_type))
+ return -EINVAL;
+
+ return 0;
+}
+
+static u64 insn_array_mem_usage(const struct bpf_map *map)
+{
+ return insn_array_alloc_size(map->max_entries);
+}
+
+static int insn_array_map_direct_value_addr(const struct bpf_map *map, u64 *imm, u32 off)
+{
+ struct bpf_insn_array *insn_array = cast_insn_array(map);
+
+ if ((off % sizeof(long)) != 0 ||
+ (off / sizeof(long)) >= map->max_entries)
+ return -EINVAL;
+
+ /* from BPF's point of view, this map is a jump table */
+ *imm = (unsigned long)insn_array->ips + off;
+
+ return 0;
+}
+
+BTF_ID_LIST_SINGLE(insn_array_btf_ids, struct, bpf_insn_array)
+
+const struct bpf_map_ops insn_array_map_ops = {
+ .map_alloc_check = insn_array_alloc_check,
+ .map_alloc = insn_array_alloc,
+ .map_free = insn_array_free,
+ .map_get_next_key = bpf_array_get_next_key,
+ .map_lookup_elem = insn_array_lookup_elem,
+ .map_update_elem = insn_array_update_elem,
+ .map_delete_elem = insn_array_delete_elem,
+ .map_check_btf = insn_array_check_btf,
+ .map_mem_usage = insn_array_mem_usage,
+ .map_direct_value_addr = insn_array_map_direct_value_addr,
+ .map_btf_id = &insn_array_btf_ids[0],
+};
+
+static inline bool is_frozen(struct bpf_map *map)
+{
+ guard(mutex)(&map->freeze_mutex);
+
+ return map->frozen;
+}
+
+static bool is_insn_array(const struct bpf_map *map)
+{
+ return map->map_type == BPF_MAP_TYPE_INSN_ARRAY;
+}
+
+static inline bool valid_offsets(const struct bpf_insn_array *insn_array,
+ const struct bpf_prog *prog)
+{
+ u32 off;
+ int i;
+
+ for (i = 0; i < insn_array->map.max_entries; i++) {
+ off = insn_array->values[i].orig_off;
+
+ if (off >= prog->len)
+ return false;
+
+ if (off > 0) {
+ if (prog->insnsi[off-1].code == (BPF_LD | BPF_DW | BPF_IMM))
+ return false;
+ }
+ }
+
+ return true;
+}
+
+int bpf_insn_array_init(struct bpf_map *map, const struct bpf_prog *prog)
+{
+ struct bpf_insn_array *insn_array = cast_insn_array(map);
+ struct bpf_insn_array_value *values = insn_array->values;
+ int i;
+
+ if (!is_frozen(map))
+ return -EINVAL;
+
+ if (!valid_offsets(insn_array, prog))
+ return -EINVAL;
+
+ /*
+ * There can be only one program using the map
+ */
+ if (atomic_xchg(&insn_array->used, 1))
+ return -EBUSY;
+
+ /*
+ * Reset all the map indexes to the original values. This is needed,
+ * e.g., when a replay of verification with different log level should
+ * be performed.
+ */
+ for (i = 0; i < map->max_entries; i++)
+ values[i].xlated_off = values[i].orig_off;
+
+ return 0;
+}
+
+int bpf_insn_array_ready(struct bpf_map *map)
+{
+ struct bpf_insn_array *insn_array = cast_insn_array(map);
+ int i;
+
+ for (i = 0; i < map->max_entries; i++) {
+ if (insn_array->values[i].xlated_off == INSN_DELETED)
+ continue;
+ if (!insn_array->ips[i])
+ return -EFAULT;
+ }
+
+ return 0;
+}
+
+void bpf_insn_array_release(struct bpf_map *map)
+{
+ struct bpf_insn_array *insn_array = cast_insn_array(map);
+
+ atomic_set(&insn_array->used, 0);
+}
+
+void bpf_insn_array_adjust(struct bpf_map *map, u32 off, u32 len)
+{
+ struct bpf_insn_array *insn_array = cast_insn_array(map);
+ int i;
+
+ if (len <= 1)
+ return;
+
+ for (i = 0; i < map->max_entries; i++) {
+ if (insn_array->values[i].xlated_off <= off)
+ continue;
+ if (insn_array->values[i].xlated_off == INSN_DELETED)
+ continue;
+ insn_array->values[i].xlated_off += len - 1;
+ }
+}
+
+void bpf_insn_array_adjust_after_remove(struct bpf_map *map, u32 off, u32 len)
+{
+ struct bpf_insn_array *insn_array = cast_insn_array(map);
+ int i;
+
+ for (i = 0; i < map->max_entries; i++) {
+ if (insn_array->values[i].xlated_off < off)
+ continue;
+ if (insn_array->values[i].xlated_off == INSN_DELETED)
+ continue;
+ if (insn_array->values[i].xlated_off < off + len)
+ insn_array->values[i].xlated_off = INSN_DELETED;
+ else
+ insn_array->values[i].xlated_off -= len;
+ }
+}
+
+/*
+ * This function is called by JITs. The image is the real program
+ * image, the offsets array set up the xlated -> jitted mapping.
+ * The offsets[xlated] offset should point to the beginning of
+ * the jitted instruction.
+ */
+void bpf_prog_update_insn_ptrs(struct bpf_prog *prog, u32 *offsets, void *image)
+{
+ struct bpf_insn_array *insn_array;
+ struct bpf_map *map;
+ u32 xlated_off;
+ int i, j;
+
+ if (!offsets || !image)
+ return;
+
+ for (i = 0; i < prog->aux->used_map_cnt; i++) {
+ map = prog->aux->used_maps[i];
+ if (!is_insn_array(map))
+ continue;
+
+ insn_array = cast_insn_array(map);
+ for (j = 0; j < map->max_entries; j++) {
+ xlated_off = insn_array->values[j].xlated_off;
+ if (xlated_off == INSN_DELETED)
+ continue;
+ if (xlated_off < prog->aux->subprog_start)
+ continue;
+ xlated_off -= prog->aux->subprog_start;
+ if (xlated_off >= prog->len)
+ continue;
+
+ insn_array->values[j].jitted_off = offsets[xlated_off];
+ insn_array->ips[j] = (long)(image + offsets[xlated_off]);
+ }
+ }
+}
diff --git a/kernel/bpf/bpf_local_storage.c b/kernel/bpf/bpf_local_storage.c
index b931fbceb54d..e2fe6c32822b 100644
--- a/kernel/bpf/bpf_local_storage.c
+++ b/kernel/bpf/bpf_local_storage.c
@@ -73,30 +73,24 @@ static bool selem_linked_to_map(const struct bpf_local_storage_elem *selem)
struct bpf_local_storage_elem *
bpf_selem_alloc(struct bpf_local_storage_map *smap, void *owner,
- void *value, bool charge_mem, bool swap_uptrs, gfp_t gfp_flags)
+ void *value, bool swap_uptrs, gfp_t gfp_flags)
{
struct bpf_local_storage_elem *selem;
- if (charge_mem && mem_charge(smap, owner, smap->elem_size))
+ if (mem_charge(smap, owner, smap->elem_size))
return NULL;
- if (smap->bpf_ma) {
- selem = bpf_mem_cache_alloc_flags(&smap->selem_ma, gfp_flags);
- if (selem)
- /* Keep the original bpf_map_kzalloc behavior
- * before started using the bpf_mem_cache_alloc.
- *
- * No need to use zero_map_value. The bpf_selem_free()
- * only does bpf_mem_cache_free when there is
- * no other bpf prog is using the selem.
- */
- memset(SDATA(selem)->data, 0, smap->map.value_size);
+ if (smap->use_kmalloc_nolock) {
+ selem = bpf_map_kmalloc_nolock(&smap->map, smap->elem_size,
+ __GFP_ZERO, NUMA_NO_NODE);
} else {
selem = bpf_map_kzalloc(&smap->map, smap->elem_size,
gfp_flags | __GFP_NOWARN);
}
if (selem) {
+ RCU_INIT_POINTER(SDATA(selem)->smap, smap);
+
if (value) {
/* No need to call check_and_init_map_value as memory is zero init */
copy_map_value(&smap->map, SDATA(selem)->data, value);
@@ -106,13 +100,12 @@ bpf_selem_alloc(struct bpf_local_storage_map *smap, void *owner,
return selem;
}
- if (charge_mem)
- mem_uncharge(smap, owner, smap->elem_size);
+ mem_uncharge(smap, owner, smap->elem_size);
return NULL;
}
-/* rcu tasks trace callback for bpf_ma == false */
+/* rcu tasks trace callback for use_kmalloc_nolock == false */
static void __bpf_local_storage_free_trace_rcu(struct rcu_head *rcu)
{
struct bpf_local_storage *local_storage;
@@ -127,12 +120,23 @@ static void __bpf_local_storage_free_trace_rcu(struct rcu_head *rcu)
kfree_rcu(local_storage, rcu);
}
+/* Handle use_kmalloc_nolock == false */
+static void __bpf_local_storage_free(struct bpf_local_storage *local_storage,
+ bool vanilla_rcu)
+{
+ if (vanilla_rcu)
+ kfree_rcu(local_storage, rcu);
+ else
+ call_rcu_tasks_trace(&local_storage->rcu,
+ __bpf_local_storage_free_trace_rcu);
+}
+
static void bpf_local_storage_free_rcu(struct rcu_head *rcu)
{
struct bpf_local_storage *local_storage;
local_storage = container_of(rcu, struct bpf_local_storage, rcu);
- bpf_mem_cache_raw_free(local_storage);
+ kfree_nolock(local_storage);
}
static void bpf_local_storage_free_trace_rcu(struct rcu_head *rcu)
@@ -143,46 +147,27 @@ static void bpf_local_storage_free_trace_rcu(struct rcu_head *rcu)
call_rcu(rcu, bpf_local_storage_free_rcu);
}
-/* Handle bpf_ma == false */
-static void __bpf_local_storage_free(struct bpf_local_storage *local_storage,
- bool vanilla_rcu)
-{
- if (vanilla_rcu)
- kfree_rcu(local_storage, rcu);
- else
- call_rcu_tasks_trace(&local_storage->rcu,
- __bpf_local_storage_free_trace_rcu);
-}
-
static void bpf_local_storage_free(struct bpf_local_storage *local_storage,
- struct bpf_local_storage_map *smap,
- bool bpf_ma, bool reuse_now)
+ bool reuse_now)
{
if (!local_storage)
return;
- if (!bpf_ma) {
+ if (!local_storage->use_kmalloc_nolock) {
__bpf_local_storage_free(local_storage, reuse_now);
return;
}
- if (!reuse_now) {
- call_rcu_tasks_trace(&local_storage->rcu,
- bpf_local_storage_free_trace_rcu);
+ if (reuse_now) {
+ call_rcu(&local_storage->rcu, bpf_local_storage_free_rcu);
return;
}
- if (smap)
- bpf_mem_cache_free(&smap->storage_ma, local_storage);
- else
- /* smap could be NULL if the selem that triggered
- * this 'local_storage' creation had been long gone.
- * In this case, directly do call_rcu().
- */
- call_rcu(&local_storage->rcu, bpf_local_storage_free_rcu);
+ call_rcu_tasks_trace(&local_storage->rcu,
+ bpf_local_storage_free_trace_rcu);
}
-/* rcu tasks trace callback for bpf_ma == false */
+/* rcu tasks trace callback for use_kmalloc_nolock == false */
static void __bpf_selem_free_trace_rcu(struct rcu_head *rcu)
{
struct bpf_local_storage_elem *selem;
@@ -194,7 +179,7 @@ static void __bpf_selem_free_trace_rcu(struct rcu_head *rcu)
kfree_rcu(selem, rcu);
}
-/* Handle bpf_ma == false */
+/* Handle use_kmalloc_nolock == false */
static void __bpf_selem_free(struct bpf_local_storage_elem *selem,
bool vanilla_rcu)
{
@@ -216,7 +201,7 @@ static void bpf_selem_free_rcu(struct rcu_head *rcu)
migrate_disable();
bpf_obj_free_fields(smap->map.record, SDATA(selem)->data);
migrate_enable();
- bpf_mem_cache_raw_free(selem);
+ kfree_nolock(selem);
}
static void bpf_selem_free_trace_rcu(struct rcu_head *rcu)
@@ -228,14 +213,17 @@ static void bpf_selem_free_trace_rcu(struct rcu_head *rcu)
}
void bpf_selem_free(struct bpf_local_storage_elem *selem,
- struct bpf_local_storage_map *smap,
bool reuse_now)
{
- if (!smap->bpf_ma) {
- /* Only task storage has uptrs and task storage
- * has moved to bpf_mem_alloc. Meaning smap->bpf_ma == true
- * for task storage, so this bpf_obj_free_fields() won't unpin
- * any uptr.
+ struct bpf_local_storage_map *smap;
+
+ smap = rcu_dereference_check(SDATA(selem)->smap, bpf_rcu_lock_held());
+
+ if (!smap->use_kmalloc_nolock) {
+ /*
+ * No uptr will be unpin even when reuse_now == false since uptr
+ * is only supported in task local storage, where
+ * smap->use_kmalloc_nolock == true.
*/
bpf_obj_free_fields(smap->map.record, SDATA(selem)->data);
__bpf_selem_free(selem, reuse_now);
@@ -243,18 +231,11 @@ void bpf_selem_free(struct bpf_local_storage_elem *selem,
}
if (reuse_now) {
- /* reuse_now == true only happens when the storage owner
- * (e.g. task_struct) is being destructed or the map itself
- * is being destructed (ie map_free). In both cases,
- * no bpf prog can have a hold on the selem. It is
- * safe to unpin the uptrs and free the selem now.
- */
- bpf_obj_free_fields(smap->map.record, SDATA(selem)->data);
- /* Instead of using the vanilla call_rcu(),
- * bpf_mem_cache_free will be able to reuse selem
- * immediately.
+ /*
+ * While it is okay to call bpf_obj_free_fields() that unpins uptr when
+ * reuse_now == true, keep it in bpf_selem_free_rcu() for simplicity.
*/
- bpf_mem_cache_free(&smap->selem_ma, selem);
+ call_rcu(&selem->rcu, bpf_selem_free_rcu);
return;
}
@@ -264,7 +245,6 @@ void bpf_selem_free(struct bpf_local_storage_elem *selem,
static void bpf_selem_free_list(struct hlist_head *list, bool reuse_now)
{
struct bpf_local_storage_elem *selem;
- struct bpf_local_storage_map *smap;
struct hlist_node *n;
/* The "_safe" iteration is needed.
@@ -272,10 +252,8 @@ static void bpf_selem_free_list(struct hlist_head *list, bool reuse_now)
* but bpf_selem_free will use the selem->rcu_head
* which is union-ized with the selem->free_node.
*/
- hlist_for_each_entry_safe(selem, n, list, free_node) {
- smap = rcu_dereference_check(SDATA(selem)->smap, bpf_rcu_lock_held());
- bpf_selem_free(selem, smap, reuse_now);
- }
+ hlist_for_each_entry_safe(selem, n, list, free_node)
+ bpf_selem_free(selem, reuse_now);
}
/* local_storage->lock must be held and selem->local_storage == local_storage.
@@ -284,7 +262,7 @@ static void bpf_selem_free_list(struct hlist_head *list, bool reuse_now)
*/
static bool bpf_selem_unlink_storage_nolock(struct bpf_local_storage *local_storage,
struct bpf_local_storage_elem *selem,
- bool uncharge_mem, struct hlist_head *free_selem_list)
+ struct hlist_head *free_selem_list)
{
struct bpf_local_storage_map *smap;
bool free_local_storage;
@@ -297,8 +275,7 @@ static bool bpf_selem_unlink_storage_nolock(struct bpf_local_storage *local_stor
* The owner may be freed once the last selem is unlinked
* from local_storage.
*/
- if (uncharge_mem)
- mem_uncharge(smap, owner, smap->elem_size);
+ mem_uncharge(smap, owner, smap->elem_size);
free_local_storage = hlist_is_singular_node(&selem->snode,
&local_storage->list);
@@ -336,47 +313,11 @@ static bool bpf_selem_unlink_storage_nolock(struct bpf_local_storage *local_stor
return free_local_storage;
}
-static bool check_storage_bpf_ma(struct bpf_local_storage *local_storage,
- struct bpf_local_storage_map *storage_smap,
- struct bpf_local_storage_elem *selem)
-{
-
- struct bpf_local_storage_map *selem_smap;
-
- /* local_storage->smap may be NULL. If it is, get the bpf_ma
- * from any selem in the local_storage->list. The bpf_ma of all
- * local_storage and selem should have the same value
- * for the same map type.
- *
- * If the local_storage->list is already empty, the caller will not
- * care about the bpf_ma value also because the caller is not
- * responsible to free the local_storage.
- */
-
- if (storage_smap)
- return storage_smap->bpf_ma;
-
- if (!selem) {
- struct hlist_node *n;
-
- n = rcu_dereference_check(hlist_first_rcu(&local_storage->list),
- bpf_rcu_lock_held());
- if (!n)
- return false;
-
- selem = hlist_entry(n, struct bpf_local_storage_elem, snode);
- }
- selem_smap = rcu_dereference_check(SDATA(selem)->smap, bpf_rcu_lock_held());
-
- return selem_smap->bpf_ma;
-}
-
static void bpf_selem_unlink_storage(struct bpf_local_storage_elem *selem,
bool reuse_now)
{
- struct bpf_local_storage_map *storage_smap;
struct bpf_local_storage *local_storage;
- bool bpf_ma, free_local_storage = false;
+ bool free_local_storage = false;
HLIST_HEAD(selem_free_list);
unsigned long flags;
@@ -386,20 +327,17 @@ static void bpf_selem_unlink_storage(struct bpf_local_storage_elem *selem,
local_storage = rcu_dereference_check(selem->local_storage,
bpf_rcu_lock_held());
- storage_smap = rcu_dereference_check(local_storage->smap,
- bpf_rcu_lock_held());
- bpf_ma = check_storage_bpf_ma(local_storage, storage_smap, selem);
raw_spin_lock_irqsave(&local_storage->lock, flags);
if (likely(selem_linked_to_storage(selem)))
free_local_storage = bpf_selem_unlink_storage_nolock(
- local_storage, selem, true, &selem_free_list);
+ local_storage, selem, &selem_free_list);
raw_spin_unlock_irqrestore(&local_storage->lock, flags);
bpf_selem_free_list(&selem_free_list, reuse_now);
if (free_local_storage)
- bpf_local_storage_free(local_storage, storage_smap, bpf_ma, reuse_now);
+ bpf_local_storage_free(local_storage, reuse_now);
}
void bpf_selem_link_storage_nolock(struct bpf_local_storage *local_storage,
@@ -434,7 +372,6 @@ void bpf_selem_link_map(struct bpf_local_storage_map *smap,
unsigned long flags;
raw_spin_lock_irqsave(&b->lock, flags);
- RCU_INIT_POINTER(SDATA(selem)->smap, smap);
hlist_add_head_rcu(&selem->map_node, &b->list);
raw_spin_unlock_irqrestore(&b->lock, flags);
}
@@ -493,8 +430,9 @@ int bpf_local_storage_alloc(void *owner,
if (err)
return err;
- if (smap->bpf_ma)
- storage = bpf_mem_cache_alloc_flags(&smap->storage_ma, gfp_flags);
+ if (smap->use_kmalloc_nolock)
+ storage = bpf_map_kmalloc_nolock(&smap->map, sizeof(*storage),
+ __GFP_ZERO, NUMA_NO_NODE);
else
storage = bpf_map_kzalloc(&smap->map, sizeof(*storage),
gfp_flags | __GFP_NOWARN);
@@ -507,6 +445,7 @@ int bpf_local_storage_alloc(void *owner,
INIT_HLIST_HEAD(&storage->list);
raw_spin_lock_init(&storage->lock);
storage->owner = owner;
+ storage->use_kmalloc_nolock = smap->use_kmalloc_nolock;
bpf_selem_link_storage_nolock(storage, first_selem);
bpf_selem_link_map(smap, first_selem);
@@ -528,22 +467,12 @@ int bpf_local_storage_alloc(void *owner,
bpf_selem_unlink_map(first_selem);
err = -EAGAIN;
goto uncharge;
-
- /* Note that even first_selem was linked to smap's
- * bucket->list, first_selem can be freed immediately
- * (instead of kfree_rcu) because
- * bpf_local_storage_map_free() does a
- * synchronize_rcu_mult (waiting for both sleepable and
- * normal programs) before walking the bucket->list.
- * Hence, no one is accessing selem from the
- * bucket->list under rcu_read_lock().
- */
}
return 0;
uncharge:
- bpf_local_storage_free(storage, smap, smap->bpf_ma, true);
+ bpf_local_storage_free(storage, true);
mem_uncharge(smap, owner, sizeof(*storage));
return err;
}
@@ -582,13 +511,13 @@ bpf_local_storage_update(void *owner, struct bpf_local_storage_map *smap,
if (err)
return ERR_PTR(err);
- selem = bpf_selem_alloc(smap, owner, value, true, swap_uptrs, gfp_flags);
+ selem = bpf_selem_alloc(smap, owner, value, swap_uptrs, gfp_flags);
if (!selem)
return ERR_PTR(-ENOMEM);
err = bpf_local_storage_alloc(owner, smap, selem, gfp_flags);
if (err) {
- bpf_selem_free(selem, smap, true);
+ bpf_selem_free(selem, true);
mem_uncharge(smap, owner, smap->elem_size);
return ERR_PTR(err);
}
@@ -616,7 +545,7 @@ bpf_local_storage_update(void *owner, struct bpf_local_storage_map *smap,
/* A lookup has just been done before and concluded a new selem is
* needed. The chance of an unnecessary alloc is unlikely.
*/
- alloc_selem = selem = bpf_selem_alloc(smap, owner, value, true, swap_uptrs, gfp_flags);
+ alloc_selem = selem = bpf_selem_alloc(smap, owner, value, swap_uptrs, gfp_flags);
if (!alloc_selem)
return ERR_PTR(-ENOMEM);
@@ -656,7 +585,7 @@ bpf_local_storage_update(void *owner, struct bpf_local_storage_map *smap,
if (old_sdata) {
bpf_selem_unlink_map(SELEM(old_sdata));
bpf_selem_unlink_storage_nolock(local_storage, SELEM(old_sdata),
- true, &old_selem_free_list);
+ &old_selem_free_list);
}
unlock:
@@ -664,7 +593,7 @@ unlock:
bpf_selem_free_list(&old_selem_free_list, false);
if (alloc_selem) {
mem_uncharge(smap, owner, smap->elem_size);
- bpf_selem_free(alloc_selem, smap, true);
+ bpf_selem_free(alloc_selem, true);
}
return err ? ERR_PTR(err) : SDATA(selem);
}
@@ -730,16 +659,12 @@ int bpf_local_storage_map_check_btf(const struct bpf_map *map,
void bpf_local_storage_destroy(struct bpf_local_storage *local_storage)
{
- struct bpf_local_storage_map *storage_smap;
struct bpf_local_storage_elem *selem;
- bool bpf_ma, free_storage = false;
+ bool free_storage = false;
HLIST_HEAD(free_selem_list);
struct hlist_node *n;
unsigned long flags;
- storage_smap = rcu_dereference_check(local_storage->smap, bpf_rcu_lock_held());
- bpf_ma = check_storage_bpf_ma(local_storage, storage_smap, NULL);
-
/* 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
@@ -762,14 +687,14 @@ void bpf_local_storage_destroy(struct bpf_local_storage *local_storage)
* of the loop will set the free_cgroup_storage to true.
*/
free_storage = bpf_selem_unlink_storage_nolock(
- local_storage, selem, true, &free_selem_list);
+ local_storage, selem, &free_selem_list);
}
raw_spin_unlock_irqrestore(&local_storage->lock, flags);
bpf_selem_free_list(&free_selem_list, true);
if (free_storage)
- bpf_local_storage_free(local_storage, storage_smap, bpf_ma, true);
+ bpf_local_storage_free(local_storage, true);
}
u64 bpf_local_storage_map_mem_usage(const struct bpf_map *map)
@@ -782,20 +707,10 @@ u64 bpf_local_storage_map_mem_usage(const struct bpf_map *map)
return usage;
}
-/* When bpf_ma == true, the bpf_mem_alloc is used to allocate and free memory.
- * A deadlock free allocator is useful for storage that the bpf prog can easily
- * get a hold of the owner PTR_TO_BTF_ID in any context. eg. bpf_get_current_task_btf.
- * The task and cgroup storage fall into this case. The bpf_mem_alloc reuses
- * memory immediately. To be reuse-immediate safe, the owner destruction
- * code path needs to go through a rcu grace period before calling
- * bpf_local_storage_destroy().
- *
- * When bpf_ma == false, the kmalloc and kfree are used.
- */
struct bpf_map *
bpf_local_storage_map_alloc(union bpf_attr *attr,
struct bpf_local_storage_cache *cache,
- bool bpf_ma)
+ bool use_kmalloc_nolock)
{
struct bpf_local_storage_map *smap;
unsigned int i;
@@ -829,20 +744,9 @@ bpf_local_storage_map_alloc(union bpf_attr *attr,
/* In PREEMPT_RT, kmalloc(GFP_ATOMIC) is still not safe in non
* preemptible context. Thus, enforce all storages to use
- * bpf_mem_alloc when CONFIG_PREEMPT_RT is enabled.
+ * kmalloc_nolock() when CONFIG_PREEMPT_RT is enabled.
*/
- smap->bpf_ma = IS_ENABLED(CONFIG_PREEMPT_RT) ? true : bpf_ma;
- if (smap->bpf_ma) {
- err = bpf_mem_alloc_init(&smap->selem_ma, smap->elem_size, false);
- if (err)
- goto free_smap;
-
- err = bpf_mem_alloc_init(&smap->storage_ma, sizeof(struct bpf_local_storage), false);
- if (err) {
- bpf_mem_alloc_destroy(&smap->selem_ma);
- goto free_smap;
- }
- }
+ smap->use_kmalloc_nolock = IS_ENABLED(CONFIG_PREEMPT_RT) ? true : use_kmalloc_nolock;
smap->cache_idx = bpf_local_storage_cache_idx_get(cache);
return &smap->map;
@@ -912,12 +816,9 @@ voi