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Commit 05949f63 authored by Alexei Starovoitov's avatar Alexei Starovoitov
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Merge branch 'autogen-bpf-helpers' 

Andrii Nakryiko says:

====================
This patch set adds ability to auto-generate list of BPF helper definitions.
It relies on existing scripts/bpf_helpers_doc.py and include/uapi/linux/bpf.h
having a well-defined set of comments. bpf_helper_defs.h contains all BPF
helper signatures which stay in sync with latest bpf.h UAPI. This
auto-generated header is included from bpf_helpers.h, while all previously
hand-written BPF helper definitions are simultaneously removed in patch #3.
The end result is less manually maintained and redundant boilerplate code,
while also more consistent and well-documented set of BPF helpers. Generated
helper definitions are completely independent from a specific bpf.h on
a target system, because it doesn't use BPF_FUNC_xxx enums.

v3->v4:
- instead of libbpf's Makefile, integrate with selftest/bpf's Makefile (Alexei);

v2->v3:
- delete bpf_helper_defs.h properly (Alexei);

v1->v2:
- add bpf_helper_defs.h to .gitignore and `make clean` (Alexei).
====================
Signed-off-by: default avatarAlexei Starovoitov <ast@kernel.org>
parents a9eb048d 24f25763
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Showing with 195 additions and 297 deletions
include/uapi/linux/bpf.h
View file @ 05949f63
......@@ -794,7 +794,7 @@ union bpf_attr {
* A 64-bit integer containing the current GID and UID, and
* created as such: *current_gid* **<< 32 \|** *current_uid*.
*
* int bpf_get_current_comm(char *buf, u32 size_of_buf)
* int bpf_get_current_comm(void *buf, u32 size_of_buf)
* Description
* Copy the **comm** attribute of the current task into *buf* of
* *size_of_buf*. The **comm** attribute contains the name of
......@@ -1023,7 +1023,7 @@ union bpf_attr {
* The realm of the route for the packet associated to *skb*, or 0
* if none was found.
*
* int bpf_perf_event_output(struct pt_regs *ctx, struct bpf_map *map, u64 flags, void *data, u64 size)
* int bpf_perf_event_output(void *ctx, struct bpf_map *map, u64 flags, void *data, u64 size)
* Description
* Write raw *data* blob into a special BPF perf event held by
* *map* of type **BPF_MAP_TYPE_PERF_EVENT_ARRAY**. This perf
......@@ -1068,7 +1068,7 @@ union bpf_attr {
* Return
* 0 on success, or a negative error in case of failure.
*
* int bpf_skb_load_bytes(const struct sk_buff *skb, u32 offset, void *to, u32 len)
* int bpf_skb_load_bytes(const void *skb, u32 offset, void *to, u32 len)
* Description
* This helper was provided as an easy way to load data from a
* packet. It can be used to load *len* bytes from *offset* from
......@@ -1085,7 +1085,7 @@ union bpf_attr {
* Return
* 0 on success, or a negative error in case of failure.
*
* int bpf_get_stackid(struct pt_regs *ctx, struct bpf_map *map, u64 flags)
* int bpf_get_stackid(void *ctx, struct bpf_map *map, u64 flags)
* Description
* Walk a user or a kernel stack and return its id. To achieve
* this, the helper needs *ctx*, which is a pointer to the context
......@@ -1154,7 +1154,7 @@ union bpf_attr {
* The checksum result, or a negative error code in case of
* failure.
*
* int bpf_skb_get_tunnel_opt(struct sk_buff *skb, u8 *opt, u32 size)
* int bpf_skb_get_tunnel_opt(struct sk_buff *skb, void *opt, u32 size)
* Description
* Retrieve tunnel options metadata for the packet associated to
* *skb*, and store the raw tunnel option data to the buffer *opt*
......@@ -1172,7 +1172,7 @@ union bpf_attr {
* Return
* The size of the option data retrieved.
*
* int bpf_skb_set_tunnel_opt(struct sk_buff *skb, u8 *opt, u32 size)
* int bpf_skb_set_tunnel_opt(struct sk_buff *skb, void *opt, u32 size)
* Description
* Set tunnel options metadata for the packet associated to *skb*
* to the option data contained in the raw buffer *opt* of *size*.
......@@ -1511,7 +1511,7 @@ union bpf_attr {
* Return
* 0
*
* int bpf_setsockopt(struct bpf_sock_ops *bpf_socket, int level, int optname, char *optval, int optlen)
* int bpf_setsockopt(struct bpf_sock_ops *bpf_socket, int level, int optname, void *optval, int optlen)
* Description
* Emulate a call to **setsockopt()** on the socket associated to
* *bpf_socket*, which must be a full socket. The *level* at
......@@ -1595,7 +1595,7 @@ union bpf_attr {
* Return
* **XDP_REDIRECT** on success, or **XDP_ABORTED** on error.
*
* int bpf_sk_redirect_map(struct bpf_map *map, u32 key, u64 flags)
* int bpf_sk_redirect_map(struct sk_buff *skb, struct bpf_map *map, u32 key, u64 flags)
* Description
* Redirect the packet to the socket referenced by *map* (of type
* **BPF_MAP_TYPE_SOCKMAP**) at index *key*. Both ingress and
......@@ -1715,7 +1715,7 @@ union bpf_attr {
* Return
* 0 on success, or a negative error in case of failure.
*
* int bpf_getsockopt(struct bpf_sock_ops *bpf_socket, int level, int optname, char *optval, int optlen)
* int bpf_getsockopt(struct bpf_sock_ops *bpf_socket, int level, int optname, void *optval, int optlen)
* Description
* Emulate a call to **getsockopt()** on the socket associated to
* *bpf_socket*, which must be a full socket. The *level* at
......@@ -1947,7 +1947,7 @@ union bpf_attr {
* Return
* 0 on success, or a negative error in case of failure.
*
* int bpf_get_stack(struct pt_regs *regs, void *buf, u32 size, u64 flags)
* int bpf_get_stack(void *ctx, void *buf, u32 size, u64 flags)
* Description
* Return a user or a kernel stack in bpf program provided buffer.
* To achieve this, the helper needs *ctx*, which is a pointer
......@@ -1980,7 +1980,7 @@ union bpf_attr {
* A non-negative value equal to or less than *size* on success,
* or a negative error in case of failure.
*
* int bpf_skb_load_bytes_relative(const struct sk_buff *skb, u32 offset, void *to, u32 len, u32 start_header)
* int bpf_skb_load_bytes_relative(const void *skb, u32 offset, void *to, u32 len, u32 start_header)
* Description
* This helper is similar to **bpf_skb_load_bytes**\ () in that
* it provides an easy way to load *len* bytes from *offset*
......@@ -2033,7 +2033,7 @@ union bpf_attr {
* * > 0 one of **BPF_FIB_LKUP_RET_** codes explaining why the
* packet is not forwarded or needs assist from full stack
*
* int bpf_sock_hash_update(struct bpf_sock_ops_kern *skops, struct bpf_map *map, void *key, u64 flags)
* int bpf_sock_hash_update(struct bpf_sock_ops *skops, struct bpf_map *map, void *key, u64 flags)
* Description
* Add an entry to, or update a sockhash *map* referencing sockets.
* The *skops* is used as a new value for the entry associated to
......@@ -2392,7 +2392,7 @@ union bpf_attr {
* Return
* 0 on success, or a negative error in case of failure.
*
* int bpf_msg_push_data(struct sk_buff *skb, u32 start, u32 len, u64 flags)
* int bpf_msg_push_data(struct sk_msg_buff *msg, u32 start, u32 len, u64 flags)
* Description
* For socket policies, insert *len* bytes into *msg* at offset
* *start*.
......@@ -2408,9 +2408,9 @@ union bpf_attr {
* Return
* 0 on success, or a negative error in case of failure.
*
* int bpf_msg_pop_data(struct sk_msg_buff *msg, u32 start, u32 pop, u64 flags)
* int bpf_msg_pop_data(struct sk_msg_buff *msg, u32 start, u32 len, u64 flags)
* Description
* Will remove *pop* bytes from a *msg* starting at byte *start*.
* Will remove *len* bytes from a *msg* starting at byte *start*.
* This may result in **ENOMEM** errors under certain situations if
* an allocation and copy are required due to a full ring buffer.
* However, the helper will try to avoid doing the allocation
......@@ -2505,7 +2505,7 @@ union bpf_attr {
* A **struct bpf_tcp_sock** pointer on success, or **NULL** in
* case of failure.
*
* int bpf_skb_ecn_set_ce(struct sk_buf *skb)
* int bpf_skb_ecn_set_ce(struct sk_buff *skb)
* Description
* Set ECN (Explicit Congestion Notification) field of IP header
* to **CE** (Congestion Encountered) if current value is **ECT**
......
scripts/bpf_helpers_doc.py
View file @ 05949f63
......@@ -391,6 +391,154 @@ SEE ALSO
print('')
class PrinterHelpers(Printer):
"""
A printer for dumping collected information about helpers as C header to
be included from BPF program.
@helpers: array of Helper objects to print to standard output
"""
type_fwds = [
'struct bpf_fib_lookup',
'struct bpf_perf_event_data',
'struct bpf_perf_event_value',
'struct bpf_sock',
'struct bpf_sock_addr',
'struct bpf_sock_ops',
'struct bpf_sock_tuple',
'struct bpf_spin_lock',
'struct bpf_sysctl',
'struct bpf_tcp_sock',
'struct bpf_tunnel_key',
'struct bpf_xfrm_state',
'struct pt_regs',
'struct sk_reuseport_md',
'struct sockaddr',
'struct tcphdr',
'struct __sk_buff',
'struct sk_msg_md',
'struct xpd_md',
]
known_types = {
'...',
'void',
'const void',
'char',
'const char',
'int',
'long',
'unsigned long',
'__be16',
'__be32',
'__wsum',
'struct bpf_fib_lookup',
'struct bpf_perf_event_data',
'struct bpf_perf_event_value',
'struct bpf_sock',
'struct bpf_sock_addr',
'struct bpf_sock_ops',
'struct bpf_sock_tuple',
'struct bpf_spin_lock',
'struct bpf_sysctl',
'struct bpf_tcp_sock',
'struct bpf_tunnel_key',
'struct bpf_xfrm_state',
'struct pt_regs',
'struct sk_reuseport_md',
'struct sockaddr',
'struct tcphdr',
}
mapped_types = {
'u8': '__u8',
'u16': '__u16',
'u32': '__u32',
'u64': '__u64',
's8': '__s8',
's16': '__s16',
's32': '__s32',
's64': '__s64',
'size_t': 'unsigned long',
'struct bpf_map': 'void',
'struct sk_buff': 'struct __sk_buff',
'const struct sk_buff': 'const struct __sk_buff',
'struct sk_msg_buff': 'struct sk_msg_md',
'struct xdp_buff': 'struct xdp_md',
}
def print_header(self):
header = '''\
/* This is auto-generated file. See bpf_helpers_doc.py for details. */
/* Forward declarations of BPF structs */'''
print(header)
for fwd in self.type_fwds:
print('%s;' % fwd)
print('')
def print_footer(self):
footer = ''
print(footer)
def map_type(self, t):
if t in self.known_types:
return t
if t in self.mapped_types:
return self.mapped_types[t]
print("")
print("Unrecognized type '%s', please add it to known types!" % t)
sys.exit(1)
seen_helpers = set()
def print_one(self, helper):
proto = helper.proto_break_down()
if proto['name'] in self.seen_helpers:
return
self.seen_helpers.add(proto['name'])
print('/*')
print(" * %s" % proto['name'])
print(" *")
if (helper.desc):
# Do not strip all newline characters: formatted code at the end of
# a section must be followed by a blank line.
for line in re.sub('\n$', '', helper.desc, count=1).split('\n'):
print(' *{}{}'.format(' \t' if line else '', line))
if (helper.ret):
print(' *')
print(' * Returns')
for line in helper.ret.rstrip().split('\n'):
print(' *{}{}'.format(' \t' if line else '', line))
print(' */')
print('static %s %s(*%s)(' % (self.map_type(proto['ret_type']),
proto['ret_star'], proto['name']), end='')
comma = ''
for i, a in enumerate(proto['args']):
t = a['type']
n = a['name']
if proto['name'] == 'bpf_get_socket_cookie' and i == 0:
t = 'void'
n = 'ctx'
one_arg = '{}{}'.format(comma, self.map_type(t))
if n:
if a['star']:
one_arg += ' {}'.format(a['star'])
else:
one_arg += ' '
one_arg += '{}'.format(n)
comma = ', '
print(one_arg, end='')
print(') = (void *) %d;' % len(self.seen_helpers))
print('')
###############################################################################
# If script is launched from scripts/ from kernel tree and can access
......@@ -405,6 +553,8 @@ Parse eBPF header file and generate documentation for eBPF helper functions.
The RST-formatted output produced can be turned into a manual page with the
rst2man utility.
""")
argParser.add_argument('--header', action='store_true',
help='generate C header file')
if (os.path.isfile(bpfh)):
argParser.add_argument('--filename', help='path to include/uapi/linux/bpf.h',
default=bpfh)
......@@ -417,5 +567,8 @@ headerParser = HeaderParser(args.filename)
headerParser.run()
# Print formatted output to standard output.
printer = PrinterRST(headerParser.helpers)
if args.header:
printer = PrinterHelpers(headerParser.helpers)
else:
printer = PrinterRST(headerParser.helpers)
printer.print_all()
tools/include/uapi/linux/bpf.h
View file @ 05949f63
......@@ -794,7 +794,7 @@ union bpf_attr {
* A 64-bit integer containing the current GID and UID, and
* created as such: *current_gid* **<< 32 \|** *current_uid*.
*
* int bpf_get_current_comm(char *buf, u32 size_of_buf)
* int bpf_get_current_comm(void *buf, u32 size_of_buf)
* Description
* Copy the **comm** attribute of the current task into *buf* of
* *size_of_buf*. The **comm** attribute contains the name of
......@@ -1023,7 +1023,7 @@ union bpf_attr {
* The realm of the route for the packet associated to *skb*, or 0
* if none was found.
*
* int bpf_perf_event_output(struct pt_regs *ctx, struct bpf_map *map, u64 flags, void *data, u64 size)
* int bpf_perf_event_output(void *ctx, struct bpf_map *map, u64 flags, void *data, u64 size)
* Description
* Write raw *data* blob into a special BPF perf event held by
* *map* of type **BPF_MAP_TYPE_PERF_EVENT_ARRAY**. This perf
......@@ -1068,7 +1068,7 @@ union bpf_attr {
* Return
* 0 on success, or a negative error in case of failure.
*
* int bpf_skb_load_bytes(const struct sk_buff *skb, u32 offset, void *to, u32 len)
* int bpf_skb_load_bytes(const void *skb, u32 offset, void *to, u32 len)
* Description
* This helper was provided as an easy way to load data from a
* packet. It can be used to load *len* bytes from *offset* from
......@@ -1085,7 +1085,7 @@ union bpf_attr {
* Return
* 0 on success, or a negative error in case of failure.
*
* int bpf_get_stackid(struct pt_regs *ctx, struct bpf_map *map, u64 flags)
* int bpf_get_stackid(void *ctx, struct bpf_map *map, u64 flags)
* Description
* Walk a user or a kernel stack and return its id. To achieve
* this, the helper needs *ctx*, which is a pointer to the context
......@@ -1154,7 +1154,7 @@ union bpf_attr {
* The checksum result, or a negative error code in case of
* failure.
*
* int bpf_skb_get_tunnel_opt(struct sk_buff *skb, u8 *opt, u32 size)
* int bpf_skb_get_tunnel_opt(struct sk_buff *skb, void *opt, u32 size)
* Description
* Retrieve tunnel options metadata for the packet associated to
* *skb*, and store the raw tunnel option data to the buffer *opt*
......@@ -1172,7 +1172,7 @@ union bpf_attr {
* Return
* The size of the option data retrieved.
*
* int bpf_skb_set_tunnel_opt(struct sk_buff *skb, u8 *opt, u32 size)
* int bpf_skb_set_tunnel_opt(struct sk_buff *skb, void *opt, u32 size)
* Description
* Set tunnel options metadata for the packet associated to *skb*
* to the option data contained in the raw buffer *opt* of *size*.
......@@ -1511,7 +1511,7 @@ union bpf_attr {
* Return
* 0
*
* int bpf_setsockopt(struct bpf_sock_ops *bpf_socket, int level, int optname, char *optval, int optlen)
* int bpf_setsockopt(struct bpf_sock_ops *bpf_socket, int level, int optname, void *optval, int optlen)
* Description
* Emulate a call to **setsockopt()** on the socket associated to
* *bpf_socket*, which must be a full socket. The *level* at
......@@ -1595,7 +1595,7 @@ union bpf_attr {
* Return
* **XDP_REDIRECT** on success, or **XDP_ABORTED** on error.
*
* int bpf_sk_redirect_map(struct bpf_map *map, u32 key, u64 flags)
* int bpf_sk_redirect_map(struct sk_buff *skb, struct bpf_map *map, u32 key, u64 flags)
* Description
* Redirect the packet to the socket referenced by *map* (of type
* **BPF_MAP_TYPE_SOCKMAP**) at index *key*. Both ingress and
......@@ -1715,7 +1715,7 @@ union bpf_attr {
* Return
* 0 on success, or a negative error in case of failure.
*
* int bpf_getsockopt(struct bpf_sock_ops *bpf_socket, int level, int optname, char *optval, int optlen)
* int bpf_getsockopt(struct bpf_sock_ops *bpf_socket, int level, int optname, void *optval, int optlen)
* Description
* Emulate a call to **getsockopt()** on the socket associated to
* *bpf_socket*, which must be a full socket. The *level* at
......@@ -1947,7 +1947,7 @@ union bpf_attr {
* Return
* 0 on success, or a negative error in case of failure.
*
* int bpf_get_stack(struct pt_regs *regs, void *buf, u32 size, u64 flags)
* int bpf_get_stack(void *ctx, void *buf, u32 size, u64 flags)
* Description
* Return a user or a kernel stack in bpf program provided buffer.
* To achieve this, the helper needs *ctx*, which is a pointer
......@@ -1980,7 +1980,7 @@ union bpf_attr {
* A non-negative value equal to or less than *size* on success,
* or a negative error in case of failure.
*
* int bpf_skb_load_bytes_relative(const struct sk_buff *skb, u32 offset, void *to, u32 len, u32 start_header)
* int bpf_skb_load_bytes_relative(const void *skb, u32 offset, void *to, u32 len, u32 start_header)
* Description
* This helper is similar to **bpf_skb_load_bytes**\ () in that
* it provides an easy way to load *len* bytes from *offset*
......@@ -2033,7 +2033,7 @@ union bpf_attr {
* * > 0 one of **BPF_FIB_LKUP_RET_** codes explaining why the
* packet is not forwarded or needs assist from full stack
*
* int bpf_sock_hash_update(struct bpf_sock_ops_kern *skops, struct bpf_map *map, void *key, u64 flags)
* int bpf_sock_hash_update(struct bpf_sock_ops *skops, struct bpf_map *map, void *key, u64 flags)
* Description
* Add an entry to, or update a sockhash *map* referencing sockets.
* The *skops* is used as a new value for the entry associated to
......@@ -2392,7 +2392,7 @@ union bpf_attr {
* Return
* 0 on success, or a negative error in case of failure.
*
* int bpf_msg_push_data(struct sk_buff *skb, u32 start, u32 len, u64 flags)
* int bpf_msg_push_data(struct sk_msg_buff *msg, u32 start, u32 len, u64 flags)
* Description
* For socket policies, insert *len* bytes into *msg* at offset
* *start*.
......@@ -2408,9 +2408,9 @@ union bpf_attr {
* Return
* 0 on success, or a negative error in case of failure.
*
* int bpf_msg_pop_data(struct sk_msg_buff *msg, u32 start, u32 pop, u64 flags)
* int bpf_msg_pop_data(struct sk_msg_buff *msg, u32 start, u32 len, u64 flags)
* Description
* Will remove *pop* bytes from a *msg* starting at byte *start*.
* Will remove *len* bytes from a *msg* starting at byte *start*.
* This may result in **ENOMEM** errors under certain situations if
* an allocation and copy are required due to a full ring buffer.
* However, the helper will try to avoid doing the allocation
......@@ -2505,7 +2505,7 @@ union bpf_attr {
* A **struct bpf_tcp_sock** pointer on success, or **NULL** in
* case of failure.
*
* int bpf_skb_ecn_set_ce(struct sk_buf *skb)
* int bpf_skb_ecn_set_ce(struct sk_buff *skb)
* Description
* Set ECN (Explicit Congestion Notification) field of IP header
* to **CE** (Congestion Encountered) if current value is **ECT**
......
tools/testing/selftests/bpf/.gitignore
View file @ 05949f63
......@@ -39,3 +39,4 @@ libbpf.so.*
test_hashmap
test_btf_dump
xdping
/bpf_helper_defs.h
tools/testing/selftests/bpf/Makefile
View file @ 05949f63
......@@ -90,6 +90,10 @@ include ../lib.mk
TEST_CUSTOM_PROGS = $(OUTPUT)/urandom_read
all: $(TEST_CUSTOM_PROGS)
bpf_helper_defs.h: $(APIDIR)/linux/bpf.h
$(BPFDIR)/../../../scripts/bpf_helpers_doc.py --header \
--file $(APIDIR)/linux/bpf.h > bpf_helper_defs.h
$(OUTPUT)/urandom_read: $(OUTPUT)/%: %.c
$(CC) -o $@ $< -Wl,--build-id
......@@ -123,7 +127,7 @@ $(OUTPUT)/test_cgroup_attach: cgroup_helpers.c
# force a rebuild of BPFOBJ when its dependencies are updated
force:
$(BPFOBJ): force
$(BPFOBJ): force bpf_helper_defs.h
$(MAKE) -C $(BPFDIR) OUTPUT=$(OUTPUT)/
PROBE := $(shell $(LLC) -march=bpf -mcpu=probe -filetype=null /dev/null 2>&1)
......@@ -319,4 +323,4 @@ $(VERIFIER_TESTS_H): $(VERIFIER_TEST_FILES) | $(VERIFIER_TESTS_DIR)
EXTRA_CLEAN := $(TEST_CUSTOM_PROGS) $(ALU32_BUILD_DIR) $(BPF_GCC_BUILD_DIR) \
$(VERIFIER_TESTS_H) $(PROG_TESTS_H) $(MAP_TESTS_H) \
feature
feature bpf_helper_defs.h
tools/testing/selftests/bpf/bpf_helpers.h
View file @ 05949f63
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