* [PATCH net-next 1/7] bpf: add 'flags' attribute to BPF_MAP_UPDATE_ELEM command
2014-11-04 2:54 ` Alexei Starovoitov
@ 2014-11-04 2:54 ` Alexei Starovoitov
-1 siblings, 0 replies; 24+ messages in thread
From: Alexei Starovoitov @ 2014-11-04 2:54 UTC (permalink / raw)
To: David S. Miller
Cc: Ingo Molnar, Andy Lutomirski, Daniel Borkmann,
Hannes Frederic Sowa, Eric Dumazet,
linux-api-u79uwXL29TY76Z2rM5mHXA, netdev-u79uwXL29TY76Z2rM5mHXA,
linux-kernel-u79uwXL29TY76Z2rM5mHXA
the current meaning of BPF_MAP_UPDATE_ELEM syscall command is:
either update existing map element or create a new one.
Initially the plan was to add a new command to handle the case of
'create new element if it didn't exist', but 'flags' style looks
cleaner and overall diff is much smaller (more code reused), so add 'flags'
attribute to BPF_MAP_UPDATE_ELEM command with the following meaning:
enum {
BPF_MAP_UPDATE_OR_CREATE = 0, /* add new element or update existing */
BPF_MAP_CREATE_ONLY, /* add new element if it didn't exist */
BPF_MAP_UPDATE_ONLY /* update existing element */
};
BPF_MAP_CREATE_ONLY can fail with EEXIST if element already exists.
BPF_MAP_UPDATE_ONLY can fail with ENOENT if element doesn't exist.
Userspace will call it as:
int bpf_update_elem(int fd, void *key, void *value, __u64 flags)
{
union bpf_attr attr = {
.map_fd = fd,
.key = ptr_to_u64(key),
.value = ptr_to_u64(value),
.flags = flags;
};
return bpf(BPF_MAP_UPDATE_ELEM, &attr, sizeof(attr));
}
Signed-off-by: Alexei Starovoitov <ast-uqk4Ao+rVK5Wk0Htik3J/w@public.gmane.org>
---
include/linux/bpf.h | 2 +-
include/uapi/linux/bpf.h | 10 +++++++++-
kernel/bpf/syscall.c | 4 ++--
3 files changed, 12 insertions(+), 4 deletions(-)
diff --git a/include/linux/bpf.h b/include/linux/bpf.h
index 3cf91754a957..51e9242e4803 100644
--- a/include/linux/bpf.h
+++ b/include/linux/bpf.h
@@ -22,7 +22,7 @@ struct bpf_map_ops {
/* funcs callable from userspace and from eBPF programs */
void *(*map_lookup_elem)(struct bpf_map *map, void *key);
- int (*map_update_elem)(struct bpf_map *map, void *key, void *value);
+ int (*map_update_elem)(struct bpf_map *map, void *key, void *value, u64 flags);
int (*map_delete_elem)(struct bpf_map *map, void *key);
};
diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h
index d18316f9e9c4..19c7ae4a4dd5 100644
--- a/include/uapi/linux/bpf.h
+++ b/include/uapi/linux/bpf.h
@@ -82,7 +82,7 @@ enum bpf_cmd {
/* create or update key/value pair in a given map
* err = bpf(BPF_MAP_UPDATE_ELEM, union bpf_attr *attr, u32 size)
- * Using attr->map_fd, attr->key, attr->value
+ * Using attr->map_fd, attr->key, attr->value, attr->flags
* returns zero or negative error
*/
BPF_MAP_UPDATE_ELEM,
@@ -117,6 +117,13 @@ enum bpf_prog_type {
BPF_PROG_TYPE_UNSPEC,
};
+/* flags for BPF_MAP_UPDATE_ELEM command */
+enum bpf_map_update_flags {
+ BPF_MAP_UPDATE_OR_CREATE = 0, /* add new element or update existing */
+ BPF_MAP_CREATE_ONLY, /* add new element if it didn't exist */
+ BPF_MAP_UPDATE_ONLY /* update existing element */
+};
+
union bpf_attr {
struct { /* anonymous struct used by BPF_MAP_CREATE command */
__u32 map_type; /* one of enum bpf_map_type */
@@ -132,6 +139,7 @@ union bpf_attr {
__aligned_u64 value;
__aligned_u64 next_key;
};
+ __u64 flags;
};
struct { /* anonymous struct used by BPF_PROG_LOAD command */
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index ba61c8c16032..c0d03bf317a2 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -190,7 +190,7 @@ err_put:
return err;
}
-#define BPF_MAP_UPDATE_ELEM_LAST_FIELD value
+#define BPF_MAP_UPDATE_ELEM_LAST_FIELD flags
static int map_update_elem(union bpf_attr *attr)
{
@@ -231,7 +231,7 @@ static int map_update_elem(union bpf_attr *attr)
* therefore all map accessors rely on this fact, so do the same here
*/
rcu_read_lock();
- err = map->ops->map_update_elem(map, key, value);
+ err = map->ops->map_update_elem(map, key, value, attr->flags);
rcu_read_unlock();
free_value:
--
1.7.9.5
^ permalink raw reply related [flat|nested] 24+ messages in thread* [PATCH net-next 1/7] bpf: add 'flags' attribute to BPF_MAP_UPDATE_ELEM command
@ 2014-11-04 2:54 ` Alexei Starovoitov
0 siblings, 0 replies; 24+ messages in thread
From: Alexei Starovoitov @ 2014-11-04 2:54 UTC (permalink / raw)
To: David S. Miller
Cc: Ingo Molnar, Andy Lutomirski, Daniel Borkmann,
Hannes Frederic Sowa, Eric Dumazet, linux-api, netdev,
linux-kernel
the current meaning of BPF_MAP_UPDATE_ELEM syscall command is:
either update existing map element or create a new one.
Initially the plan was to add a new command to handle the case of
'create new element if it didn't exist', but 'flags' style looks
cleaner and overall diff is much smaller (more code reused), so add 'flags'
attribute to BPF_MAP_UPDATE_ELEM command with the following meaning:
enum {
BPF_MAP_UPDATE_OR_CREATE = 0, /* add new element or update existing */
BPF_MAP_CREATE_ONLY, /* add new element if it didn't exist */
BPF_MAP_UPDATE_ONLY /* update existing element */
};
BPF_MAP_CREATE_ONLY can fail with EEXIST if element already exists.
BPF_MAP_UPDATE_ONLY can fail with ENOENT if element doesn't exist.
Userspace will call it as:
int bpf_update_elem(int fd, void *key, void *value, __u64 flags)
{
union bpf_attr attr = {
.map_fd = fd,
.key = ptr_to_u64(key),
.value = ptr_to_u64(value),
.flags = flags;
};
return bpf(BPF_MAP_UPDATE_ELEM, &attr, sizeof(attr));
}
Signed-off-by: Alexei Starovoitov <ast@plumgrid.com>
---
include/linux/bpf.h | 2 +-
include/uapi/linux/bpf.h | 10 +++++++++-
kernel/bpf/syscall.c | 4 ++--
3 files changed, 12 insertions(+), 4 deletions(-)
diff --git a/include/linux/bpf.h b/include/linux/bpf.h
index 3cf91754a957..51e9242e4803 100644
--- a/include/linux/bpf.h
+++ b/include/linux/bpf.h
@@ -22,7 +22,7 @@ struct bpf_map_ops {
/* funcs callable from userspace and from eBPF programs */
void *(*map_lookup_elem)(struct bpf_map *map, void *key);
- int (*map_update_elem)(struct bpf_map *map, void *key, void *value);
+ int (*map_update_elem)(struct bpf_map *map, void *key, void *value, u64 flags);
int (*map_delete_elem)(struct bpf_map *map, void *key);
};
diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h
index d18316f9e9c4..19c7ae4a4dd5 100644
--- a/include/uapi/linux/bpf.h
+++ b/include/uapi/linux/bpf.h
@@ -82,7 +82,7 @@ enum bpf_cmd {
/* create or update key/value pair in a given map
* err = bpf(BPF_MAP_UPDATE_ELEM, union bpf_attr *attr, u32 size)
- * Using attr->map_fd, attr->key, attr->value
+ * Using attr->map_fd, attr->key, attr->value, attr->flags
* returns zero or negative error
*/
BPF_MAP_UPDATE_ELEM,
@@ -117,6 +117,13 @@ enum bpf_prog_type {
BPF_PROG_TYPE_UNSPEC,
};
+/* flags for BPF_MAP_UPDATE_ELEM command */
+enum bpf_map_update_flags {
+ BPF_MAP_UPDATE_OR_CREATE = 0, /* add new element or update existing */
+ BPF_MAP_CREATE_ONLY, /* add new element if it didn't exist */
+ BPF_MAP_UPDATE_ONLY /* update existing element */
+};
+
union bpf_attr {
struct { /* anonymous struct used by BPF_MAP_CREATE command */
__u32 map_type; /* one of enum bpf_map_type */
@@ -132,6 +139,7 @@ union bpf_attr {
__aligned_u64 value;
__aligned_u64 next_key;
};
+ __u64 flags;
};
struct { /* anonymous struct used by BPF_PROG_LOAD command */
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index ba61c8c16032..c0d03bf317a2 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -190,7 +190,7 @@ err_put:
return err;
}
-#define BPF_MAP_UPDATE_ELEM_LAST_FIELD value
+#define BPF_MAP_UPDATE_ELEM_LAST_FIELD flags
static int map_update_elem(union bpf_attr *attr)
{
@@ -231,7 +231,7 @@ static int map_update_elem(union bpf_attr *attr)
* therefore all map accessors rely on this fact, so do the same here
*/
rcu_read_lock();
- err = map->ops->map_update_elem(map, key, value);
+ err = map->ops->map_update_elem(map, key, value, attr->flags);
rcu_read_unlock();
free_value:
--
1.7.9.5
^ permalink raw reply related [flat|nested] 24+ messages in thread* Re: [PATCH net-next 1/7] bpf: add 'flags' attribute to BPF_MAP_UPDATE_ELEM command
2014-11-04 2:54 ` Alexei Starovoitov
(?)
@ 2014-11-04 9:25 ` Daniel Borkmann
[not found] ` <54589B89.5000309-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
-1 siblings, 1 reply; 24+ messages in thread
From: Daniel Borkmann @ 2014-11-04 9:25 UTC (permalink / raw)
To: Alexei Starovoitov
Cc: David S. Miller, Ingo Molnar, Andy Lutomirski,
Hannes Frederic Sowa, Eric Dumazet, linux-api, netdev,
linux-kernel
On 11/04/2014 03:54 AM, Alexei Starovoitov wrote:
> the current meaning of BPF_MAP_UPDATE_ELEM syscall command is:
> either update existing map element or create a new one.
> Initially the plan was to add a new command to handle the case of
> 'create new element if it didn't exist', but 'flags' style looks
> cleaner and overall diff is much smaller (more code reused), so add 'flags'
> attribute to BPF_MAP_UPDATE_ELEM command with the following meaning:
> enum {
> BPF_MAP_UPDATE_OR_CREATE = 0, /* add new element or update existing */
> BPF_MAP_CREATE_ONLY, /* add new element if it didn't exist */
> BPF_MAP_UPDATE_ONLY /* update existing element */
> };
From you commit message/code I currently don't see an explanation why
it cannot be done in typical ``flags style'' as various syscalls do,
i.e. BPF_MAP_UPDATE_OR_CREATE rather represented as ...
BPF_MAP_CREATE | BPF_MAP_UPDATE
Do you expect more than 64 different flags to be passed from user space
for BPF_MAP?
> BPF_MAP_CREATE_ONLY can fail with EEXIST if element already exists.
> BPF_MAP_UPDATE_ONLY can fail with ENOENT if element doesn't exist.
>
> Userspace will call it as:
> int bpf_update_elem(int fd, void *key, void *value, __u64 flags)
> {
> union bpf_attr attr = {
> .map_fd = fd,
> .key = ptr_to_u64(key),
> .value = ptr_to_u64(value),
> .flags = flags;
> };
>
> return bpf(BPF_MAP_UPDATE_ELEM, &attr, sizeof(attr));
> }
>
> Signed-off-by: Alexei Starovoitov <ast@plumgrid.com>
^ permalink raw reply [flat|nested] 24+ messages in thread
* [PATCH net-next 3/7] bpf: add array type of eBPF maps
2014-11-04 2:54 ` Alexei Starovoitov
@ 2014-11-04 2:54 ` Alexei Starovoitov
-1 siblings, 0 replies; 24+ messages in thread
From: Alexei Starovoitov @ 2014-11-04 2:54 UTC (permalink / raw)
To: David S. Miller
Cc: Ingo Molnar, Andy Lutomirski, Daniel Borkmann,
Hannes Frederic Sowa, Eric Dumazet,
linux-api-u79uwXL29TY76Z2rM5mHXA, netdev-u79uwXL29TY76Z2rM5mHXA,
linux-kernel-u79uwXL29TY76Z2rM5mHXA
add new map type BPF_MAP_TYPE_ARRAY and its implementation
- optimized for fastest possible lookup()
. in the future verifier/JIT may recognize lookup() with constant key
and optimize it into constant pointer. Can optimize non-constant
key into direct pointer arithmetic as well, since pointers and
value_size are constant for the life of the eBPF program.
In other words array_map_lookup_elem() may be 'inlined' by verifier/JIT
while preserving concurrent access to this map from user space
- two main use cases for array type:
. 'global' eBPF variables: array of 1 element with key=0 and value is a
collection of 'global' variables which programs can use to keep the state
between events
. aggregation of tracing events into fixed set of buckets
- all array elements pre-allocated and zero initialized at init time
- key as an index in array and can only be 4 byte
- map_delete_elem() returns EINVAL, since elements cannot be deleted
- map_update_elem() replaces elements in an non-atomic way
(for atomic updates hashtable type should be used instead)
Signed-off-by: Alexei Starovoitov <ast-uqk4Ao+rVK5Wk0Htik3J/w@public.gmane.org>
---
Note, from eBPF program and from user space, all map types are accessed
through the same API.
Example of using array type for 'global' variables from eBPF program:
struct globals {
u64 lat_ave;
u64 lat_sum;
u64 missed;
u64 max_lat;
int num_samples;
};
struct bpf_map_def SEC("maps") global_map = {
.type = BPF_MAP_TYPE_ARRAY,
.key_size = sizeof(int),
.value_size = sizeof(struct globals),
.max_entries = 1,
};
int bpf_prog(struct bpf_context *ctx)
{
...
int ind = 0;
struct globals *g = bpf_map_lookup_elem(&global_map, &ind);
if (!g)
return 0;
if (g->lat_ave == 0) {
g->num_samples++;
g->lat_sum += delta;
if (g->num_samples >= 100) {
g->lat_ave = g->lat_sum / g->num_samples;
...
The future verifier/JIT optimization will replace bpf_map_lookup_elem()
call inside eBPF program with const pointer to element value of key=0,
so that eBPF program will have no penalty whatsoever to access such
'global' variables.
At the same time user space can access this 'globals' via common map API.
Full example of both kernel and user side follows in later patches.
include/uapi/linux/bpf.h | 1 +
kernel/bpf/Makefile | 2 +-
kernel/bpf/arraymap.c | 150 ++++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 152 insertions(+), 1 deletion(-)
create mode 100644 kernel/bpf/arraymap.c
diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h
index c071f9e3a454..9811d012b766 100644
--- a/include/uapi/linux/bpf.h
+++ b/include/uapi/linux/bpf.h
@@ -112,6 +112,7 @@ enum bpf_cmd {
enum bpf_map_type {
BPF_MAP_TYPE_UNSPEC,
BPF_MAP_TYPE_HASH,
+ BPF_MAP_TYPE_ARRAY,
};
enum bpf_prog_type {
diff --git a/kernel/bpf/Makefile b/kernel/bpf/Makefile
index 2c0ec7f9da78..72ec98ba2d42 100644
--- a/kernel/bpf/Makefile
+++ b/kernel/bpf/Makefile
@@ -1,5 +1,5 @@
obj-y := core.o
-obj-$(CONFIG_BPF_SYSCALL) += syscall.o verifier.o hashtab.o
+obj-$(CONFIG_BPF_SYSCALL) += syscall.o verifier.o hashtab.o arraymap.o
ifdef CONFIG_TEST_BPF
obj-$(CONFIG_BPF_SYSCALL) += test_stub.o
endif
diff --git a/kernel/bpf/arraymap.c b/kernel/bpf/arraymap.c
new file mode 100644
index 000000000000..60212672ec9c
--- /dev/null
+++ b/kernel/bpf/arraymap.c
@@ -0,0 +1,150 @@
+/* Copyright (c) 2011-2014 PLUMgrid, http://plumgrid.com
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of version 2 of the GNU General Public
+ * License as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ */
+#include <linux/bpf.h>
+#include <linux/err.h>
+#include <linux/vmalloc.h>
+#include <linux/slab.h>
+#include <linux/mm.h>
+
+struct bpf_array {
+ struct bpf_map map;
+ u32 elem_size;
+ char value[0] __aligned(8);
+};
+
+/* Called from syscall */
+static struct bpf_map *array_map_alloc(union bpf_attr *attr)
+{
+ struct bpf_array *array;
+ u32 elem_size;
+
+ /* check sanity of attributes */
+ if (attr->max_entries == 0 || attr->key_size != 4 ||
+ attr->value_size == 0)
+ return ERR_PTR(-EINVAL);
+
+ elem_size = round_up(attr->value_size, 8);
+
+ /* allocate all map elements and zero-initialize them */
+ array = kzalloc(sizeof(*array) + attr->max_entries * elem_size,
+ GFP_USER | __GFP_NOWARN);
+ if (!array) {
+ array = vzalloc(array->map.max_entries * array->elem_size);
+ if (!array)
+ return ERR_PTR(-ENOMEM);
+ }
+
+ /* copy mandatory map attributes */
+ array->map.key_size = attr->key_size;
+ array->map.value_size = attr->value_size;
+ array->map.max_entries = attr->max_entries;
+
+ array->elem_size = elem_size;
+
+ return &array->map;
+
+}
+
+/* Called from syscall or from eBPF program */
+static void *array_map_lookup_elem(struct bpf_map *map, void *key)
+{
+ struct bpf_array *array = container_of(map, struct bpf_array, map);
+ u32 index = *(u32 *)key;
+
+ if (index >= array->map.max_entries)
+ return NULL;
+
+ return array->value + array->elem_size * index;
+}
+
+/* Called from syscall */
+static int array_map_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 = *(u32 *)key;
+ u32 *next = (u32 *)next_key;
+
+ if (index >= array->map.max_entries) {
+ *next = 0;
+ return 0;
+ }
+
+ if (index == array->map.max_entries - 1)
+ return -ENOENT;
+
+ *next = index + 1;
+ return 0;
+}
+
+/* Called from syscall or from eBPF program */
+static int array_map_update_elem(struct bpf_map *map, void *key, void *value,
+ u64 map_flags)
+{
+ struct bpf_array *array = container_of(map, struct bpf_array, map);
+ u32 index = *(u32 *)key;
+
+ if (map_flags > BPF_MAP_UPDATE_ONLY)
+ /* unknown flags */
+ return -EINVAL;
+
+ if (map_flags == BPF_MAP_CREATE_ONLY)
+ return -EINVAL;
+
+ if (index >= array->map.max_entries)
+ /* all elements were pre-allocated, cannot insert a new one */
+ return -E2BIG;
+
+ memcpy(array->value + array->elem_size * index, value, array->elem_size);
+ return 0;
+}
+
+/* Called from syscall or from eBPF program */
+static int array_map_delete_elem(struct bpf_map *map, void *key)
+{
+ return -EINVAL;
+}
+
+/* Called when map->refcnt goes to zero, either from workqueue or from syscall */
+static void array_map_free(struct bpf_map *map)
+{
+ struct bpf_array *array = container_of(map, struct bpf_array, map);
+
+ /* at this point bpf_prog->aux->refcnt == 0 and this map->refcnt == 0,
+ * so the programs (can be more than one that used this map) were
+ * disconnected from events. Wait for outstanding programs to complete
+ * and free the array
+ */
+ synchronize_rcu();
+
+ kvfree(array);
+}
+
+static struct bpf_map_ops array_ops = {
+ .map_alloc = array_map_alloc,
+ .map_free = array_map_free,
+ .map_get_next_key = array_map_get_next_key,
+ .map_lookup_elem = array_map_lookup_elem,
+ .map_update_elem = array_map_update_elem,
+ .map_delete_elem = array_map_delete_elem,
+};
+
+static struct bpf_map_type_list tl = {
+ .ops = &array_ops,
+ .type = BPF_MAP_TYPE_ARRAY,
+};
+
+static int __init register_array_map(void)
+{
+ bpf_register_map_type(&tl);
+ return 0;
+}
+late_initcall(register_array_map);
--
1.7.9.5
^ permalink raw reply related [flat|nested] 24+ messages in thread* [PATCH net-next 3/7] bpf: add array type of eBPF maps
@ 2014-11-04 2:54 ` Alexei Starovoitov
0 siblings, 0 replies; 24+ messages in thread
From: Alexei Starovoitov @ 2014-11-04 2:54 UTC (permalink / raw)
To: David S. Miller
Cc: Ingo Molnar, Andy Lutomirski, Daniel Borkmann,
Hannes Frederic Sowa, Eric Dumazet, linux-api, netdev,
linux-kernel
add new map type BPF_MAP_TYPE_ARRAY and its implementation
- optimized for fastest possible lookup()
. in the future verifier/JIT may recognize lookup() with constant key
and optimize it into constant pointer. Can optimize non-constant
key into direct pointer arithmetic as well, since pointers and
value_size are constant for the life of the eBPF program.
In other words array_map_lookup_elem() may be 'inlined' by verifier/JIT
while preserving concurrent access to this map from user space
- two main use cases for array type:
. 'global' eBPF variables: array of 1 element with key=0 and value is a
collection of 'global' variables which programs can use to keep the state
between events
. aggregation of tracing events into fixed set of buckets
- all array elements pre-allocated and zero initialized at init time
- key as an index in array and can only be 4 byte
- map_delete_elem() returns EINVAL, since elements cannot be deleted
- map_update_elem() replaces elements in an non-atomic way
(for atomic updates hashtable type should be used instead)
Signed-off-by: Alexei Starovoitov <ast@plumgrid.com>
---
Note, from eBPF program and from user space, all map types are accessed
through the same API.
Example of using array type for 'global' variables from eBPF program:
struct globals {
u64 lat_ave;
u64 lat_sum;
u64 missed;
u64 max_lat;
int num_samples;
};
struct bpf_map_def SEC("maps") global_map = {
.type = BPF_MAP_TYPE_ARRAY,
.key_size = sizeof(int),
.value_size = sizeof(struct globals),
.max_entries = 1,
};
int bpf_prog(struct bpf_context *ctx)
{
...
int ind = 0;
struct globals *g = bpf_map_lookup_elem(&global_map, &ind);
if (!g)
return 0;
if (g->lat_ave == 0) {
g->num_samples++;
g->lat_sum += delta;
if (g->num_samples >= 100) {
g->lat_ave = g->lat_sum / g->num_samples;
...
The future verifier/JIT optimization will replace bpf_map_lookup_elem()
call inside eBPF program with const pointer to element value of key=0,
so that eBPF program will have no penalty whatsoever to access such
'global' variables.
At the same time user space can access this 'globals' via common map API.
Full example of both kernel and user side follows in later patches.
include/uapi/linux/bpf.h | 1 +
kernel/bpf/Makefile | 2 +-
kernel/bpf/arraymap.c | 150 ++++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 152 insertions(+), 1 deletion(-)
create mode 100644 kernel/bpf/arraymap.c
diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h
index c071f9e3a454..9811d012b766 100644
--- a/include/uapi/linux/bpf.h
+++ b/include/uapi/linux/bpf.h
@@ -112,6 +112,7 @@ enum bpf_cmd {
enum bpf_map_type {
BPF_MAP_TYPE_UNSPEC,
BPF_MAP_TYPE_HASH,
+ BPF_MAP_TYPE_ARRAY,
};
enum bpf_prog_type {
diff --git a/kernel/bpf/Makefile b/kernel/bpf/Makefile
index 2c0ec7f9da78..72ec98ba2d42 100644
--- a/kernel/bpf/Makefile
+++ b/kernel/bpf/Makefile
@@ -1,5 +1,5 @@
obj-y := core.o
-obj-$(CONFIG_BPF_SYSCALL) += syscall.o verifier.o hashtab.o
+obj-$(CONFIG_BPF_SYSCALL) += syscall.o verifier.o hashtab.o arraymap.o
ifdef CONFIG_TEST_BPF
obj-$(CONFIG_BPF_SYSCALL) += test_stub.o
endif
diff --git a/kernel/bpf/arraymap.c b/kernel/bpf/arraymap.c
new file mode 100644
index 000000000000..60212672ec9c
--- /dev/null
+++ b/kernel/bpf/arraymap.c
@@ -0,0 +1,150 @@
+/* Copyright (c) 2011-2014 PLUMgrid, http://plumgrid.com
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of version 2 of the GNU General Public
+ * License as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ */
+#include <linux/bpf.h>
+#include <linux/err.h>
+#include <linux/vmalloc.h>
+#include <linux/slab.h>
+#include <linux/mm.h>
+
+struct bpf_array {
+ struct bpf_map map;
+ u32 elem_size;
+ char value[0] __aligned(8);
+};
+
+/* Called from syscall */
+static struct bpf_map *array_map_alloc(union bpf_attr *attr)
+{
+ struct bpf_array *array;
+ u32 elem_size;
+
+ /* check sanity of attributes */
+ if (attr->max_entries == 0 || attr->key_size != 4 ||
+ attr->value_size == 0)
+ return ERR_PTR(-EINVAL);
+
+ elem_size = round_up(attr->value_size, 8);
+
+ /* allocate all map elements and zero-initialize them */
+ array = kzalloc(sizeof(*array) + attr->max_entries * elem_size,
+ GFP_USER | __GFP_NOWARN);
+ if (!array) {
+ array = vzalloc(array->map.max_entries * array->elem_size);
+ if (!array)
+ return ERR_PTR(-ENOMEM);
+ }
+
+ /* copy mandatory map attributes */
+ array->map.key_size = attr->key_size;
+ array->map.value_size = attr->value_size;
+ array->map.max_entries = attr->max_entries;
+
+ array->elem_size = elem_size;
+
+ return &array->map;
+
+}
+
+/* Called from syscall or from eBPF program */
+static void *array_map_lookup_elem(struct bpf_map *map, void *key)
+{
+ struct bpf_array *array = container_of(map, struct bpf_array, map);
+ u32 index = *(u32 *)key;
+
+ if (index >= array->map.max_entries)
+ return NULL;
+
+ return array->value + array->elem_size * index;
+}
+
+/* Called from syscall */
+static int array_map_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 = *(u32 *)key;
+ u32 *next = (u32 *)next_key;
+
+ if (index >= array->map.max_entries) {
+ *next = 0;
+ return 0;
+ }
+
+ if (index == array->map.max_entries - 1)
+ return -ENOENT;
+
+ *next = index + 1;
+ return 0;
+}
+
+/* Called from syscall or from eBPF program */
+static int array_map_update_elem(struct bpf_map *map, void *key, void *value,
+ u64 map_flags)
+{
+ struct bpf_array *array = container_of(map, struct bpf_array, map);
+ u32 index = *(u32 *)key;
+
+ if (map_flags > BPF_MAP_UPDATE_ONLY)
+ /* unknown flags */
+ return -EINVAL;
+
+ if (map_flags == BPF_MAP_CREATE_ONLY)
+ return -EINVAL;
+
+ if (index >= array->map.max_entries)
+ /* all elements were pre-allocated, cannot insert a new one */
+ return -E2BIG;
+
+ memcpy(array->value + array->elem_size * index, value, array->elem_size);
+ return 0;
+}
+
+/* Called from syscall or from eBPF program */
+static int array_map_delete_elem(struct bpf_map *map, void *key)
+{
+ return -EINVAL;
+}
+
+/* Called when map->refcnt goes to zero, either from workqueue or from syscall */
+static void array_map_free(struct bpf_map *map)
+{
+ struct bpf_array *array = container_of(map, struct bpf_array, map);
+
+ /* at this point bpf_prog->aux->refcnt == 0 and this map->refcnt == 0,
+ * so the programs (can be more than one that used this map) were
+ * disconnected from events. Wait for outstanding programs to complete
+ * and free the array
+ */
+ synchronize_rcu();
+
+ kvfree(array);
+}
+
+static struct bpf_map_ops array_ops = {
+ .map_alloc = array_map_alloc,
+ .map_free = array_map_free,
+ .map_get_next_key = array_map_get_next_key,
+ .map_lookup_elem = array_map_lookup_elem,
+ .map_update_elem = array_map_update_elem,
+ .map_delete_elem = array_map_delete_elem,
+};
+
+static struct bpf_map_type_list tl = {
+ .ops = &array_ops,
+ .type = BPF_MAP_TYPE_ARRAY,
+};
+
+static int __init register_array_map(void)
+{
+ bpf_register_map_type(&tl);
+ return 0;
+}
+late_initcall(register_array_map);
--
1.7.9.5
^ permalink raw reply related [flat|nested] 24+ messages in thread* Re: [PATCH net-next 3/7] bpf: add array type of eBPF maps
2014-11-04 2:54 ` Alexei Starovoitov
(?)
@ 2014-11-04 9:58 ` Daniel Borkmann
2014-11-04 23:14 ` Alexei Starovoitov
-1 siblings, 1 reply; 24+ messages in thread
From: Daniel Borkmann @ 2014-11-04 9:58 UTC (permalink / raw)
To: Alexei Starovoitov
Cc: David S. Miller, Ingo Molnar, Andy Lutomirski,
Hannes Frederic Sowa, Eric Dumazet, linux-api, netdev,
linux-kernel
On 11/04/2014 03:54 AM, Alexei Starovoitov wrote:
> add new map type BPF_MAP_TYPE_ARRAY and its implementation
>
> - optimized for fastest possible lookup()
> . in the future verifier/JIT may recognize lookup() with constant key
> and optimize it into constant pointer. Can optimize non-constant
> key into direct pointer arithmetic as well, since pointers and
> value_size are constant for the life of the eBPF program.
> In other words array_map_lookup_elem() may be 'inlined' by verifier/JIT
> while preserving concurrent access to this map from user space
>
> - two main use cases for array type:
> . 'global' eBPF variables: array of 1 element with key=0 and value is a
> collection of 'global' variables which programs can use to keep the state
> between events
> . aggregation of tracing events into fixed set of buckets
>
> - all array elements pre-allocated and zero initialized at init time
>
> - key as an index in array and can only be 4 byte
>
> - map_delete_elem() returns EINVAL, since elements cannot be deleted
>
> - map_update_elem() replaces elements in an non-atomic way
> (for atomic updates hashtable type should be used instead)
>
> Signed-off-by: Alexei Starovoitov <ast@plumgrid.com>
...
> +/* Called from syscall or from eBPF program */
> +static int array_map_update_elem(struct bpf_map *map, void *key, void *value,
> + u64 map_flags)
> +{
> + struct bpf_array *array = container_of(map, struct bpf_array, map);
> + u32 index = *(u32 *)key;
> +
> + if (map_flags > BPF_MAP_UPDATE_ONLY)
> + /* unknown flags */
> + return -EINVAL;
> +
> + if (map_flags == BPF_MAP_CREATE_ONLY)
> + return -EINVAL;
> +
> + if (index >= array->map.max_entries)
> + /* all elements were pre-allocated, cannot insert a new one */
> + return -E2BIG;
> +
> + memcpy(array->value + array->elem_size * index, value, array->elem_size);
What would protect this from concurrent updates?
> + return 0;
> +}
^ permalink raw reply [flat|nested] 24+ messages in thread* Re: [PATCH net-next 3/7] bpf: add array type of eBPF maps
2014-11-04 9:58 ` Daniel Borkmann
@ 2014-11-04 23:14 ` Alexei Starovoitov
0 siblings, 0 replies; 24+ messages in thread
From: Alexei Starovoitov @ 2014-11-04 23:14 UTC (permalink / raw)
To: Daniel Borkmann
Cc: David S. Miller, Ingo Molnar, Andy Lutomirski,
Hannes Frederic Sowa, Eric Dumazet, Linux API,
Network Development, LKML
On Tue, Nov 4, 2014 at 1:58 AM, Daniel Borkmann <dborkman@redhat.com> wrote:
>> +
>> + memcpy(array->value + array->elem_size * index, value,
>> array->elem_size);
>
> What would protect this from concurrent updates?
nothing.
that's what I meant in commit log:
- map_update_elem() replaces elements in an non-atomic way
(for atomic updates hashtable type should be used instead)
The array map is like C array of structures.
Nothing protects concurrent access.
It's used in the cases where accuracy is not needed
or when there is no concurrent access.
To compute a histogram of events in tracing the array
of integers is used. Every integer is a counter. Program
increments it (may be without using xadd) and
user space periodically reads it back.
map_update_elem() is called by userspace once
to initialize it if zero-init is not enough.
Programs do lookup() and modify the values.
For array type update() method is used rarely,
delete() is never used and get_next() is needed
for completeness to browse maps through
common map API.
I'm guessing you're asking, because it may feel
that adding a lock() will help to make it more useful? ;)
It's not, since programs cannot take a lock().
^ permalink raw reply [flat|nested] 24+ messages in thread
* [PATCH net-next 5/7] bpf: add a testsuite for eBPF maps
2014-11-04 2:54 ` Alexei Starovoitov
@ 2014-11-04 2:54 ` Alexei Starovoitov
-1 siblings, 0 replies; 24+ messages in thread
From: Alexei Starovoitov @ 2014-11-04 2:54 UTC (permalink / raw)
To: David S. Miller
Cc: Ingo Molnar, Andy Lutomirski, Daniel Borkmann,
Hannes Frederic Sowa, Eric Dumazet,
linux-api-u79uwXL29TY76Z2rM5mHXA, netdev-u79uwXL29TY76Z2rM5mHXA,
linux-kernel-u79uwXL29TY76Z2rM5mHXA
. check error conditions and sanity of hash and array map APIs
. check large maps (that kernel gracefully switches to vmalloc from kmalloc)
. check multi-process parallel access and stress test
Signed-off-by: Alexei Starovoitov <ast-uqk4Ao+rVK5Wk0Htik3J/w@public.gmane.org>
---
Eventually it can be moved tools/testing/selftests/bpf/, but for now keep
it in samples/bpf/, since that's where all subsequent samples are coming to.
samples/bpf/Makefile | 3 +-
samples/bpf/libbpf.c | 3 +-
samples/bpf/libbpf.h | 2 +-
samples/bpf/test_maps.c | 287 +++++++++++++++++++++++++++++++++++++++++++++++
4 files changed, 292 insertions(+), 3 deletions(-)
create mode 100644 samples/bpf/test_maps.c
diff --git a/samples/bpf/Makefile b/samples/bpf/Makefile
index 634391797856..0718d9ce4619 100644
--- a/samples/bpf/Makefile
+++ b/samples/bpf/Makefile
@@ -2,9 +2,10 @@
obj- := dummy.o
# List of programs to build
-hostprogs-y := test_verifier
+hostprogs-y := test_verifier test_maps
test_verifier-objs := test_verifier.o libbpf.o
+test_maps-objs := test_maps.o libbpf.o
# Tell kbuild to always build the programs
always := $(hostprogs-y)
diff --git a/samples/bpf/libbpf.c b/samples/bpf/libbpf.c
index ff6504420738..17bb520eb57f 100644
--- a/samples/bpf/libbpf.c
+++ b/samples/bpf/libbpf.c
@@ -27,12 +27,13 @@ int bpf_create_map(enum bpf_map_type map_type, int key_size, int value_size,
return syscall(__NR_bpf, BPF_MAP_CREATE, &attr, sizeof(attr));
}
-int bpf_update_elem(int fd, void *key, void *value)
+int bpf_update_elem(int fd, void *key, void *value, unsigned long long flags)
{
union bpf_attr attr = {
.map_fd = fd,
.key = ptr_to_u64(key),
.value = ptr_to_u64(value),
+ .flags = flags,
};
return syscall(__NR_bpf, BPF_MAP_UPDATE_ELEM, &attr, sizeof(attr));
diff --git a/samples/bpf/libbpf.h b/samples/bpf/libbpf.h
index 8a31babeca5d..f8678e5f48bf 100644
--- a/samples/bpf/libbpf.h
+++ b/samples/bpf/libbpf.h
@@ -6,7 +6,7 @@ struct bpf_insn;
int bpf_create_map(enum bpf_map_type map_type, int key_size, int value_size,
int max_entries);
-int bpf_update_elem(int fd, void *key, void *value);
+int bpf_update_elem(int fd, void *key, void *value, unsigned long long flags);
int bpf_lookup_elem(int fd, void *key, void *value);
int bpf_delete_elem(int fd, void *key);
int bpf_get_next_key(int fd, void *key, void *next_key);
diff --git a/samples/bpf/test_maps.c b/samples/bpf/test_maps.c
new file mode 100644
index 000000000000..91614031aed0
--- /dev/null
+++ b/samples/bpf/test_maps.c
@@ -0,0 +1,287 @@
+/*
+ * Testsuite for eBPF maps
+ *
+ * Copyright (c) 2014 PLUMgrid, http://plumgrid.com
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of version 2 of the GNU General Public
+ * License as published by the Free Software Foundation.
+ */
+#include <stdio.h>
+#include <unistd.h>
+#include <linux/bpf.h>
+#include <errno.h>
+#include <string.h>
+#include <assert.h>
+#include <sys/wait.h>
+#include <stdlib.h>
+#include "libbpf.h"
+
+/* sanity tests for map API */
+static void test_hashmap_sanity(int i, void *data)
+{
+ long long key, next_key, value;
+ int map_fd;
+
+ map_fd = bpf_create_map(BPF_MAP_TYPE_HASH, sizeof(key), sizeof(value), 2);
+ if (map_fd < 0) {
+ printf("failed to create hashmap '%s'\n", strerror(errno));
+ exit(1);
+ }
+
+ key = 1;
+ value = 1234;
+ /* insert key=1 element */
+ assert(bpf_update_elem(map_fd, &key, &value, BPF_MAP_UPDATE_OR_CREATE) == 0);
+
+ value = 0;
+ assert(bpf_update_elem(map_fd, &key, &value, BPF_MAP_CREATE_ONLY) == -1 &&
+ errno == EEXIST);
+
+ assert(bpf_update_elem(map_fd, &key, &value, -1) == -1 && errno == EINVAL);
+
+ /* check that key=1 can be found */
+ assert(bpf_lookup_elem(map_fd, &key, &value) == 0 && value == 1234);
+
+ key = 2;
+ /* check that key=2 is not found */
+ assert(bpf_lookup_elem(map_fd, &key, &value) == -1 && errno == ENOENT);
+
+ assert(bpf_update_elem(map_fd, &key, &value, BPF_MAP_UPDATE_ONLY) == -1 &&
+ errno == ENOENT);
+
+ /* insert key=2 element */
+ assert(bpf_update_elem(map_fd, &key, &value, BPF_MAP_CREATE_ONLY) == 0);
+
+ /* key=1 and key=2 were inserted, check that key=0 cannot be inserted
+ * due to max_entries limit
+ */
+ key = 0;
+ assert(bpf_update_elem(map_fd, &key, &value, BPF_MAP_CREATE_ONLY) == -1 &&
+ errno == E2BIG);
+
+ /* check that key = 0 doesn't exist */
+ assert(bpf_delete_elem(map_fd, &key) == -1 && errno == ENOENT);
+
+ /* iterate over two elements */
+ assert(bpf_get_next_key(map_fd, &key, &next_key) == 0 &&
+ next_key == 2);
+ assert(bpf_get_next_key(map_fd, &next_key, &next_key) == 0 &&
+ next_key == 1);
+ assert(bpf_get_next_key(map_fd, &next_key, &next_key) == -1 &&
+ errno == ENOENT);
+
+ /* delete both elements */
+ key = 1;
+ assert(bpf_delete_elem(map_fd, &key) == 0);
+ key = 2;
+ assert(bpf_delete_elem(map_fd, &key) == 0);
+ assert(bpf_delete_elem(map_fd, &key) == -1 && errno == ENOENT);
+
+ key = 0;
+ /* check that map is empty */
+ assert(bpf_get_next_key(map_fd, &key, &next_key) == -1 &&
+ errno == ENOENT);
+ close(map_fd);
+}
+
+static void test_arraymap_sanity(int i, void *data)
+{
+ int key, next_key, map_fd;
+ long long value;
+
+ map_fd = bpf_create_map(BPF_MAP_TYPE_ARRAY, sizeof(key), sizeof(value), 2);
+ if (map_fd < 0) {
+ printf("failed to create arraymap '%s'\n", strerror(errno));
+ exit(1);
+ }
+
+ key = 1;
+ value = 1234;
+ /* insert key=1 element */
+ assert(bpf_update_elem(map_fd, &key, &value, BPF_MAP_UPDATE_OR_CREATE) == 0);
+
+ value = 0;
+ assert(bpf_update_elem(map_fd, &key, &value, BPF_MAP_CREATE_ONLY) == -1 &&
+ errno == EINVAL);
+
+ /* check that key=1 can be found */
+ assert(bpf_lookup_elem(map_fd, &key, &value) == 0 && value == 1234);
+
+ key = 0;
+ /* check that key=0 is also found and zero initialized */
+ assert(bpf_lookup_elem(map_fd, &key, &value) == 0 && value == 0);
+
+
+ /* key=0 and key=1 were inserted, check that key=2 cannot be inserted
+ * due to max_entries limit
+ */
+ key = 2;
+ assert(bpf_update_elem(map_fd, &key, &value, BPF_MAP_UPDATE_ONLY) == -1 &&
+ errno == E2BIG);
+
+ /* check that key = 2 doesn't exist */
+ assert(bpf_lookup_elem(map_fd, &key, &value) == -1 && errno == ENOENT);
+
+ /* iterate over two elements */
+ assert(bpf_get_next_key(map_fd, &key, &next_key) == 0 &&
+ next_key == 0);
+ assert(bpf_get_next_key(map_fd, &next_key, &next_key) == 0 &&
+ next_key == 1);
+ assert(bpf_get_next_key(map_fd, &next_key, &next_key) == -1 &&
+ errno == ENOENT);
+
+ /* delete shouldn't succeed */
+ key = 1;
+ assert(bpf_delete_elem(map_fd, &key) == -1 && errno == EINVAL);
+
+ close(map_fd);
+}
+
+#define MAP_SIZE (32 * 1024)
+static void test_map_large(void)
+{
+ struct bigkey {
+ int a;
+ char b[116];
+ long long c;
+ } key;
+ int map_fd, i, value;
+
+ /* allocate 4Mbyte of memory */
+ map_fd = bpf_create_map(BPF_MAP_TYPE_HASH, sizeof(key), sizeof(value),
+ MAP_SIZE);
+ if (map_fd < 0) {
+ printf("failed to create large map '%s'\n", strerror(errno));
+ exit(1);
+ }
+
+ for (i = 0; i < MAP_SIZE; i++) {
+ key = (struct bigkey) {.c = i};
+ value = i;
+ assert(bpf_update_elem(map_fd, &key, &value, BPF_MAP_CREATE_ONLY) == 0);
+ }
+ key.c = -1;
+ assert(bpf_update_elem(map_fd, &key, &value, BPF_MAP_CREATE_ONLY) == -1 &&
+ errno == E2BIG);
+
+ /* iterate through all elements */
+ for (i = 0; i < MAP_SIZE; i++)
+ assert(bpf_get_next_key(map_fd, &key, &key) == 0);
+ assert(bpf_get_next_key(map_fd, &key, &key) == -1 && errno == ENOENT);
+
+ key.c = 0;
+ assert(bpf_lookup_elem(map_fd, &key, &value) == 0 && value == 0);
+ key.a = 1;
+ assert(bpf_lookup_elem(map_fd, &key, &value) == -1 && errno == ENOENT);
+
+ close(map_fd);
+}
+
+/* fork N children and wait for them to complete */
+static void run_parallel(int tasks, void (*fn)(int i, void *data), void *data)
+{
+ pid_t pid[tasks];
+ int i;
+
+ for (i = 0; i < tasks; i++) {
+ pid[i] = fork();
+ if (pid[i] == 0) {
+ fn(i, data);
+ exit(0);
+ } else if (pid[i] == -1) {
+ printf("couldn't spawn #%d process\n", i);
+ exit(1);
+ }
+ }
+ for (i = 0; i < tasks; i++) {
+ int status;
+
+ assert(waitpid(pid[i], &status, 0) == pid[i]);
+ assert(status == 0);
+ }
+}
+
+static void test_map_stress(void)
+{
+ run_parallel(100, test_hashmap_sanity, NULL);
+ run_parallel(100, test_arraymap_sanity, NULL);
+}
+
+#define TASKS 1024
+#define DO_UPDATE 1
+#define DO_DELETE 0
+static void do_work(int fn, void *data)
+{
+ int map_fd = ((int *)data)[0];
+ int do_update = ((int *)data)[1];
+ int i;
+ int key, value;
+
+ for (i = fn; i < MAP_SIZE; i += TASKS) {
+ key = value = i;
+ if (do_update)
+ assert(bpf_update_elem(map_fd, &key, &value, BPF_MAP_CREATE_ONLY) == 0);
+ else
+ assert(bpf_delete_elem(map_fd, &key) == 0);
+ }
+}
+
+static void test_map_parallel(void)
+{
+ int i, map_fd, key = 0, value = 0;
+ int data[2];
+
+ map_fd = bpf_create_map(BPF_MAP_TYPE_HASH, sizeof(key), sizeof(value),
+ MAP_SIZE);
+ if (map_fd < 0) {
+ printf("failed to create map for parallel test '%s'\n",
+ strerror(errno));
+ exit(1);
+ }
+
+ data[0] = map_fd;
+ data[1] = DO_UPDATE;
+ /* use the same map_fd in children to add elements to this map
+ * child_0 adds key=0, key=1024, key=2048, ...
+ * child_1 adds key=1, key=1025, key=2049, ...
+ * child_1023 adds key=1023, ...
+ */
+ run_parallel(TASKS, do_work, data);
+
+ /* check that key=0 is already there */
+ assert(bpf_update_elem(map_fd, &key, &value, BPF_MAP_CREATE_ONLY) == -1 &&
+ errno == EEXIST);
+
+ /* check that all elements were inserted */
+ key = -1;
+ for (i = 0; i < MAP_SIZE; i++)
+ assert(bpf_get_next_key(map_fd, &key, &key) == 0);
+ assert(bpf_get_next_key(map_fd, &key, &key) == -1 && errno == ENOENT);
+
+ /* another check for all elements */
+ for (i = 0; i < MAP_SIZE; i++) {
+ key = MAP_SIZE - i - 1;
+ assert(bpf_lookup_elem(map_fd, &key, &value) == 0 &&
+ value == key);
+ }
+
+ /* now let's delete all elemenets in parallel */
+ data[1] = DO_DELETE;
+ run_parallel(TASKS, do_work, data);
+
+ /* nothing should be left */
+ key = -1;
+ assert(bpf_get_next_key(map_fd, &key, &key) == -1 && errno == ENOENT);
+}
+
+int main(void)
+{
+ test_hashmap_sanity(0, NULL);
+ test_arraymap_sanity(0, NULL);
+ test_map_large();
+ test_map_parallel();
+ test_map_stress();
+ printf("test_maps: OK\n");
+ return 0;
+}
--
1.7.9.5
^ permalink raw reply related [flat|nested] 24+ messages in thread* [PATCH net-next 5/7] bpf: add a testsuite for eBPF maps
@ 2014-11-04 2:54 ` Alexei Starovoitov
0 siblings, 0 replies; 24+ messages in thread
From: Alexei Starovoitov @ 2014-11-04 2:54 UTC (permalink / raw)
To: David S. Miller
Cc: Ingo Molnar, Andy Lutomirski, Daniel Borkmann,
Hannes Frederic Sowa, Eric Dumazet, linux-api, netdev,
linux-kernel
. check error conditions and sanity of hash and array map APIs
. check large maps (that kernel gracefully switches to vmalloc from kmalloc)
. check multi-process parallel access and stress test
Signed-off-by: Alexei Starovoitov <ast@plumgrid.com>
---
Eventually it can be moved tools/testing/selftests/bpf/, but for now keep
it in samples/bpf/, since that's where all subsequent samples are coming to.
samples/bpf/Makefile | 3 +-
samples/bpf/libbpf.c | 3 +-
samples/bpf/libbpf.h | 2 +-
samples/bpf/test_maps.c | 287 +++++++++++++++++++++++++++++++++++++++++++++++
4 files changed, 292 insertions(+), 3 deletions(-)
create mode 100644 samples/bpf/test_maps.c
diff --git a/samples/bpf/Makefile b/samples/bpf/Makefile
index 634391797856..0718d9ce4619 100644
--- a/samples/bpf/Makefile
+++ b/samples/bpf/Makefile
@@ -2,9 +2,10 @@
obj- := dummy.o
# List of programs to build
-hostprogs-y := test_verifier
+hostprogs-y := test_verifier test_maps
test_verifier-objs := test_verifier.o libbpf.o
+test_maps-objs := test_maps.o libbpf.o
# Tell kbuild to always build the programs
always := $(hostprogs-y)
diff --git a/samples/bpf/libbpf.c b/samples/bpf/libbpf.c
index ff6504420738..17bb520eb57f 100644
--- a/samples/bpf/libbpf.c
+++ b/samples/bpf/libbpf.c
@@ -27,12 +27,13 @@ int bpf_create_map(enum bpf_map_type map_type, int key_size, int value_size,
return syscall(__NR_bpf, BPF_MAP_CREATE, &attr, sizeof(attr));
}
-int bpf_update_elem(int fd, void *key, void *value)
+int bpf_update_elem(int fd, void *key, void *value, unsigned long long flags)
{
union bpf_attr attr = {
.map_fd = fd,
.key = ptr_to_u64(key),
.value = ptr_to_u64(value),
+ .flags = flags,
};
return syscall(__NR_bpf, BPF_MAP_UPDATE_ELEM, &attr, sizeof(attr));
diff --git a/samples/bpf/libbpf.h b/samples/bpf/libbpf.h
index 8a31babeca5d..f8678e5f48bf 100644
--- a/samples/bpf/libbpf.h
+++ b/samples/bpf/libbpf.h
@@ -6,7 +6,7 @@ struct bpf_insn;
int bpf_create_map(enum bpf_map_type map_type, int key_size, int value_size,
int max_entries);
-int bpf_update_elem(int fd, void *key, void *value);
+int bpf_update_elem(int fd, void *key, void *value, unsigned long long flags);
int bpf_lookup_elem(int fd, void *key, void *value);
int bpf_delete_elem(int fd, void *key);
int bpf_get_next_key(int fd, void *key, void *next_key);
diff --git a/samples/bpf/test_maps.c b/samples/bpf/test_maps.c
new file mode 100644
index 000000000000..91614031aed0
--- /dev/null
+++ b/samples/bpf/test_maps.c
@@ -0,0 +1,287 @@
+/*
+ * Testsuite for eBPF maps
+ *
+ * Copyright (c) 2014 PLUMgrid, http://plumgrid.com
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of version 2 of the GNU General Public
+ * License as published by the Free Software Foundation.
+ */
+#include <stdio.h>
+#include <unistd.h>
+#include <linux/bpf.h>
+#include <errno.h>
+#include <string.h>
+#include <assert.h>
+#include <sys/wait.h>
+#include <stdlib.h>
+#include "libbpf.h"
+
+/* sanity tests for map API */
+static void test_hashmap_sanity(int i, void *data)
+{
+ long long key, next_key, value;
+ int map_fd;
+
+ map_fd = bpf_create_map(BPF_MAP_TYPE_HASH, sizeof(key), sizeof(value), 2);
+ if (map_fd < 0) {
+ printf("failed to create hashmap '%s'\n", strerror(errno));
+ exit(1);
+ }
+
+ key = 1;
+ value = 1234;
+ /* insert key=1 element */
+ assert(bpf_update_elem(map_fd, &key, &value, BPF_MAP_UPDATE_OR_CREATE) == 0);
+
+ value = 0;
+ assert(bpf_update_elem(map_fd, &key, &value, BPF_MAP_CREATE_ONLY) == -1 &&
+ errno == EEXIST);
+
+ assert(bpf_update_elem(map_fd, &key, &value, -1) == -1 && errno == EINVAL);
+
+ /* check that key=1 can be found */
+ assert(bpf_lookup_elem(map_fd, &key, &value) == 0 && value == 1234);
+
+ key = 2;
+ /* check that key=2 is not found */
+ assert(bpf_lookup_elem(map_fd, &key, &value) == -1 && errno == ENOENT);
+
+ assert(bpf_update_elem(map_fd, &key, &value, BPF_MAP_UPDATE_ONLY) == -1 &&
+ errno == ENOENT);
+
+ /* insert key=2 element */
+ assert(bpf_update_elem(map_fd, &key, &value, BPF_MAP_CREATE_ONLY) == 0);
+
+ /* key=1 and key=2 were inserted, check that key=0 cannot be inserted
+ * due to max_entries limit
+ */
+ key = 0;
+ assert(bpf_update_elem(map_fd, &key, &value, BPF_MAP_CREATE_ONLY) == -1 &&
+ errno == E2BIG);
+
+ /* check that key = 0 doesn't exist */
+ assert(bpf_delete_elem(map_fd, &key) == -1 && errno == ENOENT);
+
+ /* iterate over two elements */
+ assert(bpf_get_next_key(map_fd, &key, &next_key) == 0 &&
+ next_key == 2);
+ assert(bpf_get_next_key(map_fd, &next_key, &next_key) == 0 &&
+ next_key == 1);
+ assert(bpf_get_next_key(map_fd, &next_key, &next_key) == -1 &&
+ errno == ENOENT);
+
+ /* delete both elements */
+ key = 1;
+ assert(bpf_delete_elem(map_fd, &key) == 0);
+ key = 2;
+ assert(bpf_delete_elem(map_fd, &key) == 0);
+ assert(bpf_delete_elem(map_fd, &key) == -1 && errno == ENOENT);
+
+ key = 0;
+ /* check that map is empty */
+ assert(bpf_get_next_key(map_fd, &key, &next_key) == -1 &&
+ errno == ENOENT);
+ close(map_fd);
+}
+
+static void test_arraymap_sanity(int i, void *data)
+{
+ int key, next_key, map_fd;
+ long long value;
+
+ map_fd = bpf_create_map(BPF_MAP_TYPE_ARRAY, sizeof(key), sizeof(value), 2);
+ if (map_fd < 0) {
+ printf("failed to create arraymap '%s'\n", strerror(errno));
+ exit(1);
+ }
+
+ key = 1;
+ value = 1234;
+ /* insert key=1 element */
+ assert(bpf_update_elem(map_fd, &key, &value, BPF_MAP_UPDATE_OR_CREATE) == 0);
+
+ value = 0;
+ assert(bpf_update_elem(map_fd, &key, &value, BPF_MAP_CREATE_ONLY) == -1 &&
+ errno == EINVAL);
+
+ /* check that key=1 can be found */
+ assert(bpf_lookup_elem(map_fd, &key, &value) == 0 && value == 1234);
+
+ key = 0;
+ /* check that key=0 is also found and zero initialized */
+ assert(bpf_lookup_elem(map_fd, &key, &value) == 0 && value == 0);
+
+
+ /* key=0 and key=1 were inserted, check that key=2 cannot be inserted
+ * due to max_entries limit
+ */
+ key = 2;
+ assert(bpf_update_elem(map_fd, &key, &value, BPF_MAP_UPDATE_ONLY) == -1 &&
+ errno == E2BIG);
+
+ /* check that key = 2 doesn't exist */
+ assert(bpf_lookup_elem(map_fd, &key, &value) == -1 && errno == ENOENT);
+
+ /* iterate over two elements */
+ assert(bpf_get_next_key(map_fd, &key, &next_key) == 0 &&
+ next_key == 0);
+ assert(bpf_get_next_key(map_fd, &next_key, &next_key) == 0 &&
+ next_key == 1);
+ assert(bpf_get_next_key(map_fd, &next_key, &next_key) == -1 &&
+ errno == ENOENT);
+
+ /* delete shouldn't succeed */
+ key = 1;
+ assert(bpf_delete_elem(map_fd, &key) == -1 && errno == EINVAL);
+
+ close(map_fd);
+}
+
+#define MAP_SIZE (32 * 1024)
+static void test_map_large(void)
+{
+ struct bigkey {
+ int a;
+ char b[116];
+ long long c;
+ } key;
+ int map_fd, i, value;
+
+ /* allocate 4Mbyte of memory */
+ map_fd = bpf_create_map(BPF_MAP_TYPE_HASH, sizeof(key), sizeof(value),
+ MAP_SIZE);
+ if (map_fd < 0) {
+ printf("failed to create large map '%s'\n", strerror(errno));
+ exit(1);
+ }
+
+ for (i = 0; i < MAP_SIZE; i++) {
+ key = (struct bigkey) {.c = i};
+ value = i;
+ assert(bpf_update_elem(map_fd, &key, &value, BPF_MAP_CREATE_ONLY) == 0);
+ }
+ key.c = -1;
+ assert(bpf_update_elem(map_fd, &key, &value, BPF_MAP_CREATE_ONLY) == -1 &&
+ errno == E2BIG);
+
+ /* iterate through all elements */
+ for (i = 0; i < MAP_SIZE; i++)
+ assert(bpf_get_next_key(map_fd, &key, &key) == 0);
+ assert(bpf_get_next_key(map_fd, &key, &key) == -1 && errno == ENOENT);
+
+ key.c = 0;
+ assert(bpf_lookup_elem(map_fd, &key, &value) == 0 && value == 0);
+ key.a = 1;
+ assert(bpf_lookup_elem(map_fd, &key, &value) == -1 && errno == ENOENT);
+
+ close(map_fd);
+}
+
+/* fork N children and wait for them to complete */
+static void run_parallel(int tasks, void (*fn)(int i, void *data), void *data)
+{
+ pid_t pid[tasks];
+ int i;
+
+ for (i = 0; i < tasks; i++) {
+ pid[i] = fork();
+ if (pid[i] == 0) {
+ fn(i, data);
+ exit(0);
+ } else if (pid[i] == -1) {
+ printf("couldn't spawn #%d process\n", i);
+ exit(1);
+ }
+ }
+ for (i = 0; i < tasks; i++) {
+ int status;
+
+ assert(waitpid(pid[i], &status, 0) == pid[i]);
+ assert(status == 0);
+ }
+}
+
+static void test_map_stress(void)
+{
+ run_parallel(100, test_hashmap_sanity, NULL);
+ run_parallel(100, test_arraymap_sanity, NULL);
+}
+
+#define TASKS 1024
+#define DO_UPDATE 1
+#define DO_DELETE 0
+static void do_work(int fn, void *data)
+{
+ int map_fd = ((int *)data)[0];
+ int do_update = ((int *)data)[1];
+ int i;
+ int key, value;
+
+ for (i = fn; i < MAP_SIZE; i += TASKS) {
+ key = value = i;
+ if (do_update)
+ assert(bpf_update_elem(map_fd, &key, &value, BPF_MAP_CREATE_ONLY) == 0);
+ else
+ assert(bpf_delete_elem(map_fd, &key) == 0);
+ }
+}
+
+static void test_map_parallel(void)
+{
+ int i, map_fd, key = 0, value = 0;
+ int data[2];
+
+ map_fd = bpf_create_map(BPF_MAP_TYPE_HASH, sizeof(key), sizeof(value),
+ MAP_SIZE);
+ if (map_fd < 0) {
+ printf("failed to create map for parallel test '%s'\n",
+ strerror(errno));
+ exit(1);
+ }
+
+ data[0] = map_fd;
+ data[1] = DO_UPDATE;
+ /* use the same map_fd in children to add elements to this map
+ * child_0 adds key=0, key=1024, key=2048, ...
+ * child_1 adds key=1, key=1025, key=2049, ...
+ * child_1023 adds key=1023, ...
+ */
+ run_parallel(TASKS, do_work, data);
+
+ /* check that key=0 is already there */
+ assert(bpf_update_elem(map_fd, &key, &value, BPF_MAP_CREATE_ONLY) == -1 &&
+ errno == EEXIST);
+
+ /* check that all elements were inserted */
+ key = -1;
+ for (i = 0; i < MAP_SIZE; i++)
+ assert(bpf_get_next_key(map_fd, &key, &key) == 0);
+ assert(bpf_get_next_key(map_fd, &key, &key) == -1 && errno == ENOENT);
+
+ /* another check for all elements */
+ for (i = 0; i < MAP_SIZE; i++) {
+ key = MAP_SIZE - i - 1;
+ assert(bpf_lookup_elem(map_fd, &key, &value) == 0 &&
+ value == key);
+ }
+
+ /* now let's delete all elemenets in parallel */
+ data[1] = DO_DELETE;
+ run_parallel(TASKS, do_work, data);
+
+ /* nothing should be left */
+ key = -1;
+ assert(bpf_get_next_key(map_fd, &key, &key) == -1 && errno == ENOENT);
+}
+
+int main(void)
+{
+ test_hashmap_sanity(0, NULL);
+ test_arraymap_sanity(0, NULL);
+ test_map_large();
+ test_map_parallel();
+ test_map_stress();
+ printf("test_maps: OK\n");
+ return 0;
+}
--
1.7.9.5
^ permalink raw reply related [flat|nested] 24+ messages in thread
* [PATCH net-next 6/7] bpf: allow eBPF programs to use maps
2014-11-04 2:54 ` Alexei Starovoitov
@ 2014-11-04 2:54 ` Alexei Starovoitov
-1 siblings, 0 replies; 24+ messages in thread
From: Alexei Starovoitov @ 2014-11-04 2:54 UTC (permalink / raw)
To: David S. Miller
Cc: Ingo Molnar, Andy Lutomirski, Daniel Borkmann,
Hannes Frederic Sowa, Eric Dumazet,
linux-api-u79uwXL29TY76Z2rM5mHXA, netdev-u79uwXL29TY76Z2rM5mHXA,
linux-kernel-u79uwXL29TY76Z2rM5mHXA
expose bpf_map_lookup_elem(), bpf_map_update_elem(), bpf_map_delete_elem()
map accessors to eBPF programs
Signed-off-by: Alexei Starovoitov <ast-uqk4Ao+rVK5Wk0Htik3J/w@public.gmane.org>
---
Note, these helpers are exposed as '.gpl_only = false', so non-GPL eBPF programs
can use them. That was requested by AndyL and DavidL before.
include/linux/bpf.h | 5 +++
include/uapi/linux/bpf.h | 3 ++
kernel/bpf/Makefile | 2 +-
kernel/bpf/helpers.c | 88 ++++++++++++++++++++++++++++++++++++++++++++++
4 files changed, 97 insertions(+), 1 deletion(-)
create mode 100644 kernel/bpf/helpers.c
diff --git a/include/linux/bpf.h b/include/linux/bpf.h
index 51e9242e4803..75e94eaa228b 100644
--- a/include/linux/bpf.h
+++ b/include/linux/bpf.h
@@ -133,4 +133,9 @@ struct bpf_prog *bpf_prog_get(u32 ufd);
/* verify correctness of eBPF program */
int bpf_check(struct bpf_prog *fp, union bpf_attr *attr);
+/* verifier prototypes for helper functions called from eBPF programs */
+extern struct bpf_func_proto bpf_map_lookup_elem_proto;
+extern struct bpf_func_proto bpf_map_update_elem_proto;
+extern struct bpf_func_proto bpf_map_delete_elem_proto;
+
#endif /* _LINUX_BPF_H */
diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h
index 9811d012b766..84a7fc3a23ec 100644
--- a/include/uapi/linux/bpf.h
+++ b/include/uapi/linux/bpf.h
@@ -160,6 +160,9 @@ union bpf_attr {
*/
enum bpf_func_id {
BPF_FUNC_unspec,
+ BPF_FUNC_map_lookup_elem, /* void *map_lookup_elem(&map, &key) */
+ BPF_FUNC_map_update_elem, /* int map_update_elem(&map, &key, &value, flags) */
+ BPF_FUNC_map_delete_elem, /* int map_delete_elem(&map, &key) */
__BPF_FUNC_MAX_ID,
};
diff --git a/kernel/bpf/Makefile b/kernel/bpf/Makefile
index 72ec98ba2d42..a5ae60f0b0a2 100644
--- a/kernel/bpf/Makefile
+++ b/kernel/bpf/Makefile
@@ -1,5 +1,5 @@
obj-y := core.o
-obj-$(CONFIG_BPF_SYSCALL) += syscall.o verifier.o hashtab.o arraymap.o
+obj-$(CONFIG_BPF_SYSCALL) += syscall.o verifier.o hashtab.o arraymap.o helpers.o
ifdef CONFIG_TEST_BPF
obj-$(CONFIG_BPF_SYSCALL) += test_stub.o
endif
diff --git a/kernel/bpf/helpers.c b/kernel/bpf/helpers.c
new file mode 100644
index 000000000000..3fa78babe728
--- /dev/null
+++ b/kernel/bpf/helpers.c
@@ -0,0 +1,88 @@
+/* Copyright (c) 2011-2014 PLUMgrid, http://plumgrid.com
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of version 2 of the GNU General Public
+ * License as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ */
+#include <linux/bpf.h>
+#include <linux/rcupdate.h>
+
+/* called from eBPF program under rcu lock
+ *
+ * if kernel subsystem is allowing eBPF programs to call this function,
+ * inside its own verifier_ops->get_func_proto() callback it should return
+ * bpf_map_lookup_elem_proto, so that verifier can properly checks the arguments
+ */
+static u64 bpf_map_lookup_elem(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5)
+{
+ /* verifier checked that R1 contains a valid pointer to bpf_map
+ * and R2 points to a program stack and map->key_size bytes were
+ * initialized
+ */
+ struct bpf_map *map = (struct bpf_map *) (unsigned long) r1;
+ void *key = (void *) (unsigned long) r2;
+ void *value;
+
+ WARN_ON_ONCE(!rcu_read_lock_held());
+
+ value = map->ops->map_lookup_elem(map, key);
+
+ /* lookup() returns either pointer to element value or NULL
+ * which is the meaning of PTR_TO_MAP_VALUE_OR_NULL type
+ */
+ return (unsigned long) value;
+}
+
+struct bpf_func_proto bpf_map_lookup_elem_proto = {
+ .func = bpf_map_lookup_elem,
+ .gpl_only = false,
+ .ret_type = RET_PTR_TO_MAP_VALUE_OR_NULL,
+ .arg1_type = ARG_CONST_MAP_PTR,
+ .arg2_type = ARG_PTR_TO_MAP_KEY,
+};
+
+/* called from eBPF program under rcu lock */
+static u64 bpf_map_update_elem(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5)
+{
+ struct bpf_map *map = (struct bpf_map *) (unsigned long) r1;
+ void *key = (void *) (unsigned long) r2;
+ void *value = (void *) (unsigned long) r3;
+
+ WARN_ON_ONCE(!rcu_read_lock_held());
+
+ return map->ops->map_update_elem(map, key, value, r4);
+}
+
+struct bpf_func_proto bpf_map_update_elem_proto = {
+ .func = bpf_map_update_elem,
+ .gpl_only = false,
+ .ret_type = RET_INTEGER,
+ .arg1_type = ARG_CONST_MAP_PTR,
+ .arg2_type = ARG_PTR_TO_MAP_KEY,
+ .arg3_type = ARG_PTR_TO_MAP_VALUE,
+ .arg4_type = ARG_ANYTHING,
+};
+
+/* called from eBPF program under rcu lock */
+static u64 bpf_map_delete_elem(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5)
+{
+ struct bpf_map *map = (struct bpf_map *) (unsigned long) r1;
+ void *key = (void *) (unsigned long) r2;
+
+ WARN_ON_ONCE(!rcu_read_lock_held());
+
+ return map->ops->map_delete_elem(map, key);
+}
+
+struct bpf_func_proto bpf_map_delete_elem_proto = {
+ .func = bpf_map_delete_elem,
+ .gpl_only = false,
+ .ret_type = RET_INTEGER,
+ .arg1_type = ARG_CONST_MAP_PTR,
+ .arg2_type = ARG_PTR_TO_MAP_KEY,
+};
--
1.7.9.5
^ permalink raw reply related [flat|nested] 24+ messages in thread* [PATCH net-next 6/7] bpf: allow eBPF programs to use maps
@ 2014-11-04 2:54 ` Alexei Starovoitov
0 siblings, 0 replies; 24+ messages in thread
From: Alexei Starovoitov @ 2014-11-04 2:54 UTC (permalink / raw)
To: David S. Miller
Cc: Ingo Molnar, Andy Lutomirski, Daniel Borkmann,
Hannes Frederic Sowa, Eric Dumazet, linux-api, netdev,
linux-kernel
expose bpf_map_lookup_elem(), bpf_map_update_elem(), bpf_map_delete_elem()
map accessors to eBPF programs
Signed-off-by: Alexei Starovoitov <ast@plumgrid.com>
---
Note, these helpers are exposed as '.gpl_only = false', so non-GPL eBPF programs
can use them. That was requested by AndyL and DavidL before.
include/linux/bpf.h | 5 +++
include/uapi/linux/bpf.h | 3 ++
kernel/bpf/Makefile | 2 +-
kernel/bpf/helpers.c | 88 ++++++++++++++++++++++++++++++++++++++++++++++
4 files changed, 97 insertions(+), 1 deletion(-)
create mode 100644 kernel/bpf/helpers.c
diff --git a/include/linux/bpf.h b/include/linux/bpf.h
index 51e9242e4803..75e94eaa228b 100644
--- a/include/linux/bpf.h
+++ b/include/linux/bpf.h
@@ -133,4 +133,9 @@ struct bpf_prog *bpf_prog_get(u32 ufd);
/* verify correctness of eBPF program */
int bpf_check(struct bpf_prog *fp, union bpf_attr *attr);
+/* verifier prototypes for helper functions called from eBPF programs */
+extern struct bpf_func_proto bpf_map_lookup_elem_proto;
+extern struct bpf_func_proto bpf_map_update_elem_proto;
+extern struct bpf_func_proto bpf_map_delete_elem_proto;
+
#endif /* _LINUX_BPF_H */
diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h
index 9811d012b766..84a7fc3a23ec 100644
--- a/include/uapi/linux/bpf.h
+++ b/include/uapi/linux/bpf.h
@@ -160,6 +160,9 @@ union bpf_attr {
*/
enum bpf_func_id {
BPF_FUNC_unspec,
+ BPF_FUNC_map_lookup_elem, /* void *map_lookup_elem(&map, &key) */
+ BPF_FUNC_map_update_elem, /* int map_update_elem(&map, &key, &value, flags) */
+ BPF_FUNC_map_delete_elem, /* int map_delete_elem(&map, &key) */
__BPF_FUNC_MAX_ID,
};
diff --git a/kernel/bpf/Makefile b/kernel/bpf/Makefile
index 72ec98ba2d42..a5ae60f0b0a2 100644
--- a/kernel/bpf/Makefile
+++ b/kernel/bpf/Makefile
@@ -1,5 +1,5 @@
obj-y := core.o
-obj-$(CONFIG_BPF_SYSCALL) += syscall.o verifier.o hashtab.o arraymap.o
+obj-$(CONFIG_BPF_SYSCALL) += syscall.o verifier.o hashtab.o arraymap.o helpers.o
ifdef CONFIG_TEST_BPF
obj-$(CONFIG_BPF_SYSCALL) += test_stub.o
endif
diff --git a/kernel/bpf/helpers.c b/kernel/bpf/helpers.c
new file mode 100644
index 000000000000..3fa78babe728
--- /dev/null
+++ b/kernel/bpf/helpers.c
@@ -0,0 +1,88 @@
+/* Copyright (c) 2011-2014 PLUMgrid, http://plumgrid.com
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of version 2 of the GNU General Public
+ * License as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ */
+#include <linux/bpf.h>
+#include <linux/rcupdate.h>
+
+/* called from eBPF program under rcu lock
+ *
+ * if kernel subsystem is allowing eBPF programs to call this function,
+ * inside its own verifier_ops->get_func_proto() callback it should return
+ * bpf_map_lookup_elem_proto, so that verifier can properly checks the arguments
+ */
+static u64 bpf_map_lookup_elem(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5)
+{
+ /* verifier checked that R1 contains a valid pointer to bpf_map
+ * and R2 points to a program stack and map->key_size bytes were
+ * initialized
+ */
+ struct bpf_map *map = (struct bpf_map *) (unsigned long) r1;
+ void *key = (void *) (unsigned long) r2;
+ void *value;
+
+ WARN_ON_ONCE(!rcu_read_lock_held());
+
+ value = map->ops->map_lookup_elem(map, key);
+
+ /* lookup() returns either pointer to element value or NULL
+ * which is the meaning of PTR_TO_MAP_VALUE_OR_NULL type
+ */
+ return (unsigned long) value;
+}
+
+struct bpf_func_proto bpf_map_lookup_elem_proto = {
+ .func = bpf_map_lookup_elem,
+ .gpl_only = false,
+ .ret_type = RET_PTR_TO_MAP_VALUE_OR_NULL,
+ .arg1_type = ARG_CONST_MAP_PTR,
+ .arg2_type = ARG_PTR_TO_MAP_KEY,
+};
+
+/* called from eBPF program under rcu lock */
+static u64 bpf_map_update_elem(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5)
+{
+ struct bpf_map *map = (struct bpf_map *) (unsigned long) r1;
+ void *key = (void *) (unsigned long) r2;
+ void *value = (void *) (unsigned long) r3;
+
+ WARN_ON_ONCE(!rcu_read_lock_held());
+
+ return map->ops->map_update_elem(map, key, value, r4);
+}
+
+struct bpf_func_proto bpf_map_update_elem_proto = {
+ .func = bpf_map_update_elem,
+ .gpl_only = false,
+ .ret_type = RET_INTEGER,
+ .arg1_type = ARG_CONST_MAP_PTR,
+ .arg2_type = ARG_PTR_TO_MAP_KEY,
+ .arg3_type = ARG_PTR_TO_MAP_VALUE,
+ .arg4_type = ARG_ANYTHING,
+};
+
+/* called from eBPF program under rcu lock */
+static u64 bpf_map_delete_elem(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5)
+{
+ struct bpf_map *map = (struct bpf_map *) (unsigned long) r1;
+ void *key = (void *) (unsigned long) r2;
+
+ WARN_ON_ONCE(!rcu_read_lock_held());
+
+ return map->ops->map_delete_elem(map, key);
+}
+
+struct bpf_func_proto bpf_map_delete_elem_proto = {
+ .func = bpf_map_delete_elem,
+ .gpl_only = false,
+ .ret_type = RET_INTEGER,
+ .arg1_type = ARG_CONST_MAP_PTR,
+ .arg2_type = ARG_PTR_TO_MAP_KEY,
+};
--
1.7.9.5
^ permalink raw reply related [flat|nested] 24+ messages in thread[parent not found: <1415069656-14138-7-git-send-email-ast-uqk4Ao+rVK5Wk0Htik3J/w@public.gmane.org>]
* Re: [PATCH net-next 6/7] bpf: allow eBPF programs to use maps
2014-11-04 2:54 ` Alexei Starovoitov
@ 2014-11-04 9:50 ` Daniel Borkmann
-1 siblings, 0 replies; 24+ messages in thread
From: Daniel Borkmann @ 2014-11-04 9:50 UTC (permalink / raw)
To: Alexei Starovoitov
Cc: David S. Miller, Ingo Molnar, Andy Lutomirski,
Hannes Frederic Sowa, Eric Dumazet,
linux-api-u79uwXL29TY76Z2rM5mHXA, netdev-u79uwXL29TY76Z2rM5mHXA,
linux-kernel-u79uwXL29TY76Z2rM5mHXA
On 11/04/2014 03:54 AM, Alexei Starovoitov wrote:
> expose bpf_map_lookup_elem(), bpf_map_update_elem(), bpf_map_delete_elem()
> map accessors to eBPF programs
>
> Signed-off-by: Alexei Starovoitov <ast-uqk4Ao+rVK5Wk0Htik3J/w@public.gmane.org>
...
> +#include <linux/bpf.h>
> +#include <linux/rcupdate.h>
> +
> +/* called from eBPF program under rcu lock
> + *
> + * if kernel subsystem is allowing eBPF programs to call this function,
> + * inside its own verifier_ops->get_func_proto() callback it should return
> + * bpf_map_lookup_elem_proto, so that verifier can properly checks the arguments
> + */
> +static u64 bpf_map_lookup_elem(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5)
> +{
> + /* verifier checked that R1 contains a valid pointer to bpf_map
> + * and R2 points to a program stack and map->key_size bytes were
> + * initialized
> + */
> + struct bpf_map *map = (struct bpf_map *) (unsigned long) r1;
> + void *key = (void *) (unsigned long) r2;
> + void *value;
> +
> + WARN_ON_ONCE(!rcu_read_lock_held());
> +
> + value = map->ops->map_lookup_elem(map, key);
> +
> + /* lookup() returns either pointer to element value or NULL
> + * which is the meaning of PTR_TO_MAP_VALUE_OR_NULL type
> + */
> + return (unsigned long) value;
> +}
> +
> +struct bpf_func_proto bpf_map_lookup_elem_proto = {
> + .func = bpf_map_lookup_elem,
> + .gpl_only = false,
> + .ret_type = RET_PTR_TO_MAP_VALUE_OR_NULL,
> + .arg1_type = ARG_CONST_MAP_PTR,
> + .arg2_type = ARG_PTR_TO_MAP_KEY,
> +};
> +
> +/* called from eBPF program under rcu lock */
> +static u64 bpf_map_update_elem(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5)
> +{
> + struct bpf_map *map = (struct bpf_map *) (unsigned long) r1;
> + void *key = (void *) (unsigned long) r2;
> + void *value = (void *) (unsigned long) r3;
> +
> + WARN_ON_ONCE(!rcu_read_lock_held());
> +
> + return map->ops->map_update_elem(map, key, value, r4);
> +}
> +
> +struct bpf_func_proto bpf_map_update_elem_proto = {
> + .func = bpf_map_update_elem,
> + .gpl_only = false,
> + .ret_type = RET_INTEGER,
> + .arg1_type = ARG_CONST_MAP_PTR,
> + .arg2_type = ARG_PTR_TO_MAP_KEY,
> + .arg3_type = ARG_PTR_TO_MAP_VALUE,
> + .arg4_type = ARG_ANYTHING,
> +};
> +
> +/* called from eBPF program under rcu lock */
> +static u64 bpf_map_delete_elem(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5)
> +{
> + struct bpf_map *map = (struct bpf_map *) (unsigned long) r1;
> + void *key = (void *) (unsigned long) r2;
> +
> + WARN_ON_ONCE(!rcu_read_lock_held());
> +
> + return map->ops->map_delete_elem(map, key);
> +}
These WARN_ON_ONCE(!rcu_read_lock_held()) seem odd. While I see the point that
you're holding RCU read lock on the lookup, can you elaborate on your RCU usage
here and why it's necessary for delete/update?
I suspect due to the synchronize_rcu() you're using and not using any RCU
accessors but plain memcpy() e.g. in case of the array ...?
> +struct bpf_func_proto bpf_map_delete_elem_proto = {
> + .func = bpf_map_delete_elem,
> + .gpl_only = false,
> + .ret_type = RET_INTEGER,
> + .arg1_type = ARG_CONST_MAP_PTR,
> + .arg2_type = ARG_PTR_TO_MAP_KEY,
> +};
>
^ permalink raw reply [flat|nested] 24+ messages in thread* Re: [PATCH net-next 6/7] bpf: allow eBPF programs to use maps
@ 2014-11-04 9:50 ` Daniel Borkmann
0 siblings, 0 replies; 24+ messages in thread
From: Daniel Borkmann @ 2014-11-04 9:50 UTC (permalink / raw)
To: Alexei Starovoitov
Cc: David S. Miller, Ingo Molnar, Andy Lutomirski,
Hannes Frederic Sowa, Eric Dumazet, linux-api, netdev,
linux-kernel
On 11/04/2014 03:54 AM, Alexei Starovoitov wrote:
> expose bpf_map_lookup_elem(), bpf_map_update_elem(), bpf_map_delete_elem()
> map accessors to eBPF programs
>
> Signed-off-by: Alexei Starovoitov <ast@plumgrid.com>
...
> +#include <linux/bpf.h>
> +#include <linux/rcupdate.h>
> +
> +/* called from eBPF program under rcu lock
> + *
> + * if kernel subsystem is allowing eBPF programs to call this function,
> + * inside its own verifier_ops->get_func_proto() callback it should return
> + * bpf_map_lookup_elem_proto, so that verifier can properly checks the arguments
> + */
> +static u64 bpf_map_lookup_elem(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5)
> +{
> + /* verifier checked that R1 contains a valid pointer to bpf_map
> + * and R2 points to a program stack and map->key_size bytes were
> + * initialized
> + */
> + struct bpf_map *map = (struct bpf_map *) (unsigned long) r1;
> + void *key = (void *) (unsigned long) r2;
> + void *value;
> +
> + WARN_ON_ONCE(!rcu_read_lock_held());
> +
> + value = map->ops->map_lookup_elem(map, key);
> +
> + /* lookup() returns either pointer to element value or NULL
> + * which is the meaning of PTR_TO_MAP_VALUE_OR_NULL type
> + */
> + return (unsigned long) value;
> +}
> +
> +struct bpf_func_proto bpf_map_lookup_elem_proto = {
> + .func = bpf_map_lookup_elem,
> + .gpl_only = false,
> + .ret_type = RET_PTR_TO_MAP_VALUE_OR_NULL,
> + .arg1_type = ARG_CONST_MAP_PTR,
> + .arg2_type = ARG_PTR_TO_MAP_KEY,
> +};
> +
> +/* called from eBPF program under rcu lock */
> +static u64 bpf_map_update_elem(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5)
> +{
> + struct bpf_map *map = (struct bpf_map *) (unsigned long) r1;
> + void *key = (void *) (unsigned long) r2;
> + void *value = (void *) (unsigned long) r3;
> +
> + WARN_ON_ONCE(!rcu_read_lock_held());
> +
> + return map->ops->map_update_elem(map, key, value, r4);
> +}
> +
> +struct bpf_func_proto bpf_map_update_elem_proto = {
> + .func = bpf_map_update_elem,
> + .gpl_only = false,
> + .ret_type = RET_INTEGER,
> + .arg1_type = ARG_CONST_MAP_PTR,
> + .arg2_type = ARG_PTR_TO_MAP_KEY,
> + .arg3_type = ARG_PTR_TO_MAP_VALUE,
> + .arg4_type = ARG_ANYTHING,
> +};
> +
> +/* called from eBPF program under rcu lock */
> +static u64 bpf_map_delete_elem(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5)
> +{
> + struct bpf_map *map = (struct bpf_map *) (unsigned long) r1;
> + void *key = (void *) (unsigned long) r2;
> +
> + WARN_ON_ONCE(!rcu_read_lock_held());
> +
> + return map->ops->map_delete_elem(map, key);
> +}
These WARN_ON_ONCE(!rcu_read_lock_held()) seem odd. While I see the point that
you're holding RCU read lock on the lookup, can you elaborate on your RCU usage
here and why it's necessary for delete/update?
I suspect due to the synchronize_rcu() you're using and not using any RCU
accessors but plain memcpy() e.g. in case of the array ...?
> +struct bpf_func_proto bpf_map_delete_elem_proto = {
> + .func = bpf_map_delete_elem,
> + .gpl_only = false,
> + .ret_type = RET_INTEGER,
> + .arg1_type = ARG_CONST_MAP_PTR,
> + .arg2_type = ARG_PTR_TO_MAP_KEY,
> +};
>
^ permalink raw reply [flat|nested] 24+ messages in thread* Re: [PATCH net-next 6/7] bpf: allow eBPF programs to use maps
2014-11-04 9:50 ` Daniel Borkmann
(?)
@ 2014-11-04 23:08 ` Alexei Starovoitov
-1 siblings, 0 replies; 24+ messages in thread
From: Alexei Starovoitov @ 2014-11-04 23:08 UTC (permalink / raw)
To: Daniel Borkmann
Cc: David S. Miller, Ingo Molnar, Andy Lutomirski,
Hannes Frederic Sowa, Eric Dumazet, Linux API,
Network Development, LKML
On Tue, Nov 4, 2014 at 1:50 AM, Daniel Borkmann <dborkman@redhat.com> wrote:
> These WARN_ON_ONCE(!rcu_read_lock_held()) seem odd. While I see the point
> that
> you're holding RCU read lock on the lookup, can you elaborate on your RCU
> usage
> here and why it's necessary for delete/update?
>
> I suspect due to the synchronize_rcu() you're using and not using any RCU
> accessors but plain memcpy() e.g. in case of the array ...?
Correct in case of array.
Also hash delete/update() call into lookup() internally
that is using _rcu() helpers...
Future map types might have much more
complex implementations (like LPM), so it helps
to state the rules early.
Another reason is more complex to explain:
A program that intends to access maps has to be one
rcu critical section. So all lookup/update/delete calls
are under rcu_lock_held.
Since programs by themselves cannot have WARN_ON
inside them, I've added WARN_ON in these three
functions that will be called from the programs to make
sure that kernel subsystems don't do (*prog->bpf_func)(...)
without taking rcu_lock if they intend to let programs
access maps.
Having said that in the future we might have a case
for programs that don't call into these functions at all
and execute instructions only. Those won't need
rcu_lock() wrap. I experimented with that for the
patch where I replaced pred-tree walker with eBPF
program. There is no rcu there. And no calls
to map accessors.
Has to be noted, that socket filters use rcu to
protect sk_filter pointer and program itself. So for that
use case we'll keep using rcu for foreseeable future.
For tracing filters I had to add rcu_lock() around
BPF_PROG_RUN() invocation and these WARN_ON
checks saved me a lot of headache, so I prefer to
keep them since they cost nothing when lockdep is off.
^ permalink raw reply [flat|nested] 24+ messages in thread
* [PATCH net-next 7/7] bpf: remove test map scaffolding and use proper types
2014-11-04 2:54 ` Alexei Starovoitov
@ 2014-11-04 2:54 ` Alexei Starovoitov
-1 siblings, 0 replies; 24+ messages in thread
From: Alexei Starovoitov @ 2014-11-04 2:54 UTC (permalink / raw)
To: David S. Miller
Cc: Ingo Molnar, Andy Lutomirski, Daniel Borkmann,
Hannes Frederic Sowa, Eric Dumazet,
linux-api-u79uwXL29TY76Z2rM5mHXA, netdev-u79uwXL29TY76Z2rM5mHXA,
linux-kernel-u79uwXL29TY76Z2rM5mHXA
proper types and function helpers are ready. Use them in verifier testsuite.
Remove temporary stubs
Signed-off-by: Alexei Starovoitov <ast-uqk4Ao+rVK5Wk0Htik3J/w@public.gmane.org>
---
kernel/bpf/test_stub.c | 56 +++++++------------------------------------
samples/bpf/test_verifier.c | 14 +++++------
2 files changed, 16 insertions(+), 54 deletions(-)
diff --git a/kernel/bpf/test_stub.c b/kernel/bpf/test_stub.c
index fcaddff4003e..0ceae1e6e8b5 100644
--- a/kernel/bpf/test_stub.c
+++ b/kernel/bpf/test_stub.c
@@ -18,26 +18,18 @@ struct bpf_context {
u64 arg2;
};
-static u64 test_func(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5)
-{
- return 0;
-}
-
-static struct bpf_func_proto test_funcs[] = {
- [BPF_FUNC_unspec] = {
- .func = test_func,
- .gpl_only = true,
- .ret_type = RET_PTR_TO_MAP_VALUE_OR_NULL,
- .arg1_type = ARG_CONST_MAP_PTR,
- .arg2_type = ARG_PTR_TO_MAP_KEY,
- },
-};
-
static const struct bpf_func_proto *test_func_proto(enum bpf_func_id func_id)
{
- if (func_id < 0 || func_id >= ARRAY_SIZE(test_funcs))
+ switch (func_id) {
+ case BPF_FUNC_map_lookup_elem:
+ return &bpf_map_lookup_elem_proto;
+ case BPF_FUNC_map_update_elem:
+ return &bpf_map_update_elem_proto;
+ case BPF_FUNC_map_delete_elem:
+ return &bpf_map_delete_elem_proto;
+ default:
return NULL;
- return &test_funcs[func_id];
+ }
}
static const struct bpf_context_access {
@@ -78,38 +70,8 @@ static struct bpf_prog_type_list tl_prog = {
.type = BPF_PROG_TYPE_UNSPEC,
};
-static struct bpf_map *test_map_alloc(union bpf_attr *attr)
-{
- struct bpf_map *map;
-
- map = kzalloc(sizeof(*map), GFP_USER);
- if (!map)
- return ERR_PTR(-ENOMEM);
-
- map->key_size = attr->key_size;
- map->value_size = attr->value_size;
- map->max_entries = attr->max_entries;
- return map;
-}
-
-static void test_map_free(struct bpf_map *map)
-{
- kfree(map);
-}
-
-static struct bpf_map_ops test_map_ops = {
- .map_alloc = test_map_alloc,
- .map_free = test_map_free,
-};
-
-static struct bpf_map_type_list tl_map = {
- .ops = &test_map_ops,
- .type = BPF_MAP_TYPE_UNSPEC,
-};
-
static int __init register_test_ops(void)
{
- bpf_register_map_type(&tl_map);
bpf_register_prog_type(&tl_prog);
return 0;
}
diff --git a/samples/bpf/test_verifier.c b/samples/bpf/test_verifier.c
index 63402742345e..b96175e90363 100644
--- a/samples/bpf/test_verifier.c
+++ b/samples/bpf/test_verifier.c
@@ -261,7 +261,7 @@ static struct bpf_test tests[] = {
BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
BPF_LD_MAP_FD(BPF_REG_1, 0),
- BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_unspec),
+ BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem),
BPF_EXIT_INSN(),
},
.fixup = {2},
@@ -417,7 +417,7 @@ static struct bpf_test tests[] = {
BPF_ALU64_REG(BPF_MOV, BPF_REG_2, BPF_REG_10),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
BPF_LD_MAP_FD(BPF_REG_1, 0),
- BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_unspec),
+ BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_delete_elem),
BPF_EXIT_INSN(),
},
.errstr = "fd 0 is not pointing to valid bpf_map",
@@ -430,7 +430,7 @@ static struct bpf_test tests[] = {
BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
BPF_LD_MAP_FD(BPF_REG_1, 0),
- BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_unspec),
+ BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem),
BPF_ST_MEM(BPF_DW, BPF_REG_0, 0, 0),
BPF_EXIT_INSN(),
},
@@ -445,7 +445,7 @@ static struct bpf_test tests[] = {
BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
BPF_LD_MAP_FD(BPF_REG_1, 0),
- BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_unspec),
+ BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 1),
BPF_ST_MEM(BPF_DW, BPF_REG_0, 4, 0),
BPF_EXIT_INSN(),
@@ -461,7 +461,7 @@ static struct bpf_test tests[] = {
BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
BPF_LD_MAP_FD(BPF_REG_1, 0),
- BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_unspec),
+ BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 2),
BPF_ST_MEM(BPF_DW, BPF_REG_0, 0, 0),
BPF_EXIT_INSN(),
@@ -548,7 +548,7 @@ static struct bpf_test tests[] = {
BPF_ST_MEM(BPF_DW, BPF_REG_2, -56, 0),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -56),
BPF_LD_MAP_FD(BPF_REG_1, 0),
- BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_unspec),
+ BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_delete_elem),
BPF_EXIT_INSN(),
},
.fixup = {24},
@@ -659,7 +659,7 @@ static int create_map(void)
long long key, value = 0;
int map_fd;
- map_fd = bpf_create_map(BPF_MAP_TYPE_UNSPEC, sizeof(key), sizeof(value), 1024);
+ map_fd = bpf_create_map(BPF_MAP_TYPE_HASH, sizeof(key), sizeof(value), 1024);
if (map_fd < 0) {
printf("failed to create map '%s'\n", strerror(errno));
}
--
1.7.9.5
^ permalink raw reply related [flat|nested] 24+ messages in thread* [PATCH net-next 7/7] bpf: remove test map scaffolding and use proper types
@ 2014-11-04 2:54 ` Alexei Starovoitov
0 siblings, 0 replies; 24+ messages in thread
From: Alexei Starovoitov @ 2014-11-04 2:54 UTC (permalink / raw)
To: David S. Miller
Cc: Ingo Molnar, Andy Lutomirski, Daniel Borkmann,
Hannes Frederic Sowa, Eric Dumazet, linux-api, netdev,
linux-kernel
proper types and function helpers are ready. Use them in verifier testsuite.
Remove temporary stubs
Signed-off-by: Alexei Starovoitov <ast@plumgrid.com>
---
kernel/bpf/test_stub.c | 56 +++++++------------------------------------
samples/bpf/test_verifier.c | 14 +++++------
2 files changed, 16 insertions(+), 54 deletions(-)
diff --git a/kernel/bpf/test_stub.c b/kernel/bpf/test_stub.c
index fcaddff4003e..0ceae1e6e8b5 100644
--- a/kernel/bpf/test_stub.c
+++ b/kernel/bpf/test_stub.c
@@ -18,26 +18,18 @@ struct bpf_context {
u64 arg2;
};
-static u64 test_func(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5)
-{
- return 0;
-}
-
-static struct bpf_func_proto test_funcs[] = {
- [BPF_FUNC_unspec] = {
- .func = test_func,
- .gpl_only = true,
- .ret_type = RET_PTR_TO_MAP_VALUE_OR_NULL,
- .arg1_type = ARG_CONST_MAP_PTR,
- .arg2_type = ARG_PTR_TO_MAP_KEY,
- },
-};
-
static const struct bpf_func_proto *test_func_proto(enum bpf_func_id func_id)
{
- if (func_id < 0 || func_id >= ARRAY_SIZE(test_funcs))
+ switch (func_id) {
+ case BPF_FUNC_map_lookup_elem:
+ return &bpf_map_lookup_elem_proto;
+ case BPF_FUNC_map_update_elem:
+ return &bpf_map_update_elem_proto;
+ case BPF_FUNC_map_delete_elem:
+ return &bpf_map_delete_elem_proto;
+ default:
return NULL;
- return &test_funcs[func_id];
+ }
}
static const struct bpf_context_access {
@@ -78,38 +70,8 @@ static struct bpf_prog_type_list tl_prog = {
.type = BPF_PROG_TYPE_UNSPEC,
};
-static struct bpf_map *test_map_alloc(union bpf_attr *attr)
-{
- struct bpf_map *map;
-
- map = kzalloc(sizeof(*map), GFP_USER);
- if (!map)
- return ERR_PTR(-ENOMEM);
-
- map->key_size = attr->key_size;
- map->value_size = attr->value_size;
- map->max_entries = attr->max_entries;
- return map;
-}
-
-static void test_map_free(struct bpf_map *map)
-{
- kfree(map);
-}
-
-static struct bpf_map_ops test_map_ops = {
- .map_alloc = test_map_alloc,
- .map_free = test_map_free,
-};
-
-static struct bpf_map_type_list tl_map = {
- .ops = &test_map_ops,
- .type = BPF_MAP_TYPE_UNSPEC,
-};
-
static int __init register_test_ops(void)
{
- bpf_register_map_type(&tl_map);
bpf_register_prog_type(&tl_prog);
return 0;
}
diff --git a/samples/bpf/test_verifier.c b/samples/bpf/test_verifier.c
index 63402742345e..b96175e90363 100644
--- a/samples/bpf/test_verifier.c
+++ b/samples/bpf/test_verifier.c
@@ -261,7 +261,7 @@ static struct bpf_test tests[] = {
BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
BPF_LD_MAP_FD(BPF_REG_1, 0),
- BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_unspec),
+ BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem),
BPF_EXIT_INSN(),
},
.fixup = {2},
@@ -417,7 +417,7 @@ static struct bpf_test tests[] = {
BPF_ALU64_REG(BPF_MOV, BPF_REG_2, BPF_REG_10),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
BPF_LD_MAP_FD(BPF_REG_1, 0),
- BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_unspec),
+ BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_delete_elem),
BPF_EXIT_INSN(),
},
.errstr = "fd 0 is not pointing to valid bpf_map",
@@ -430,7 +430,7 @@ static struct bpf_test tests[] = {
BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
BPF_LD_MAP_FD(BPF_REG_1, 0),
- BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_unspec),
+ BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem),
BPF_ST_MEM(BPF_DW, BPF_REG_0, 0, 0),
BPF_EXIT_INSN(),
},
@@ -445,7 +445,7 @@ static struct bpf_test tests[] = {
BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
BPF_LD_MAP_FD(BPF_REG_1, 0),
- BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_unspec),
+ BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 1),
BPF_ST_MEM(BPF_DW, BPF_REG_0, 4, 0),
BPF_EXIT_INSN(),
@@ -461,7 +461,7 @@ static struct bpf_test tests[] = {
BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
BPF_LD_MAP_FD(BPF_REG_1, 0),
- BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_unspec),
+ BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 2),
BPF_ST_MEM(BPF_DW, BPF_REG_0, 0, 0),
BPF_EXIT_INSN(),
@@ -548,7 +548,7 @@ static struct bpf_test tests[] = {
BPF_ST_MEM(BPF_DW, BPF_REG_2, -56, 0),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -56),
BPF_LD_MAP_FD(BPF_REG_1, 0),
- BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_unspec),
+ BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_delete_elem),
BPF_EXIT_INSN(),
},
.fixup = {24},
@@ -659,7 +659,7 @@ static int create_map(void)
long long key, value = 0;
int map_fd;
- map_fd = bpf_create_map(BPF_MAP_TYPE_UNSPEC, sizeof(key), sizeof(value), 1024);
+ map_fd = bpf_create_map(BPF_MAP_TYPE_HASH, sizeof(key), sizeof(value), 1024);
if (map_fd < 0) {
printf("failed to create map '%s'\n", strerror(errno));
}
--
1.7.9.5
^ permalink raw reply related [flat|nested] 24+ messages in thread