Merge branch 'bpf-array-map-offload-and-tests'

Jakub Kicinski says:

====================
This set brings in the rest of map offload code held up by urgent
fixes and improvements to the BPF arrays.

The first 3 patches take care of array map offload, similarly to
hash maps the attribute validation is split out to a separate map
op, and used for both offloaded and non-offloaded case (allocation
only happens if map is on the host).  Offload support comes down
to allowing this map type through the offload check in the core.
NFP driver also rejects the delete operation in case of array maps.

Subsequent patches add reporting of target device in a very similar
way target device of programs is reported (ifindex+netns dev/ino).
Netdevsim is extended with a trivial map implementation allowing us
to test the offload in test_offload.py.

Last patch adds a small busy wait to NFP map IO, this improves the
response times which is especially useful for map dumps.
====================

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

5 files changed, 227 insertions, 26 deletions

diff --git a/tools/bpf/bpftool/map.c b/tools/bpf/bpftool/map.c
index 8d7db9d6b9cd..a152c1a5c94c 100644
--- a/tools/bpf/bpftool/map.c
+++ b/tools/bpf/bpftool/map.c
@@ -428,6 +428,9 @@ static int show_map_close_json(int fd, struct bpf_map_info *info)
 
 	jsonw_name(json_wtr, "flags");
 	jsonw_printf(json_wtr, "%#x", info->map_flags);
+
+	print_dev_json(info->ifindex, info->netns_dev, info->netns_ino);
+
 	jsonw_uint_field(json_wtr, "bytes_key", info->key_size);
 	jsonw_uint_field(json_wtr, "bytes_value", info->value_size);
 	jsonw_uint_field(json_wtr, "max_entries", info->max_entries);
@@ -469,7 +472,9 @@ static int show_map_close_plain(int fd, struct bpf_map_info *info)
 	if (*info->name)
 		printf("name %s  ", info->name);
 
-	printf("flags 0x%x\n", info->map_flags);
+	printf("flags 0x%x", info->map_flags);
+	print_dev_plain(info->ifindex, info->netns_dev, info->netns_ino);
+	printf("\n");
 	printf("\tkey %uB  value %uB  max_entries %u",
 	       info->key_size, info->value_size, info->max_entries);
 
diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h
index 7c2259e8bc54..af1f49ad8b88 100644
--- a/tools/include/uapi/linux/bpf.h
+++ b/tools/include/uapi/linux/bpf.h
@@ -938,6 +938,9 @@ struct bpf_map_info {
 	__u32 max_entries;
 	__u32 map_flags;
 	char  name[BPF_OBJ_NAME_LEN];
+	__u32 ifindex;
+	__u64 netns_dev;
+	__u64 netns_ino;
 } __attribute__((aligned(8)));
 
 /* User bpf_sock_ops struct to access socket values and specify request ops
diff --git a/tools/testing/selftests/bpf/Makefile b/tools/testing/selftests/bpf/Makefile
index a8aa7e251c8e..3a44b655d852 100644
--- a/tools/testing/selftests/bpf/Makefile
+++ b/tools/testing/selftests/bpf/Makefile
@@ -19,7 +19,8 @@ TEST_GEN_PROGS = test_verifier test_tag test_maps test_lru_map test_lpm_map test
 TEST_GEN_FILES = test_pkt_access.o test_xdp.o test_l4lb.o test_tcp_estats.o test_obj_id.o \
 	test_pkt_md_access.o test_xdp_redirect.o test_xdp_meta.o sockmap_parse_prog.o     \
 	sockmap_verdict_prog.o dev_cgroup.o sample_ret0.o test_tracepoint.o \
-	test_l4lb_noinline.o test_xdp_noinline.o test_stacktrace_map.o
+	test_l4lb_noinline.o test_xdp_noinline.o test_stacktrace_map.o \
+	sample_map_ret0.o
 
 TEST_PROGS := test_kmod.sh test_xdp_redirect.sh test_xdp_meta.sh \
 	test_offload.py
diff --git a/tools/testing/selftests/bpf/sample_map_ret0.c b/tools/testing/selftests/bpf/sample_map_ret0.c
new file mode 100644
index 000000000000..0756303676ac
--- /dev/null
+++ b/tools/testing/selftests/bpf/sample_map_ret0.c
@@ -0,0 +1,34 @@
+/* SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause) */
+#include <linux/bpf.h>
+#include "bpf_helpers.h"
+
+struct bpf_map_def SEC("maps") htab = {
+	.type = BPF_MAP_TYPE_HASH,
+	.key_size = sizeof(__u32),
+	.value_size = sizeof(long),
+	.max_entries = 2,
+};
+
+struct bpf_map_def SEC("maps") array = {
+	.type = BPF_MAP_TYPE_ARRAY,
+	.key_size = sizeof(__u32),
+	.value_size = sizeof(long),
+	.max_entries = 2,
+};
+
+/* Sample program which should always load for testing control paths. */
+SEC(".text") int func()
+{
+	__u64 key64 = 0;
+	__u32 key = 0;
+	long *value;
+
+	value = bpf_map_lookup_elem(&htab, &key);
+	if (!value)
+		return 1;
+	value = bpf_map_lookup_elem(&array, &key64);
+	if (!value)
+		return 1;
+
+	return 0;
+}
diff --git a/tools/testing/selftests/bpf/test_offload.py b/tools/testing/selftests/bpf/test_offload.py
index e3c750f17cb8..833b9c1ec450 100755
--- a/tools/testing/selftests/bpf/test_offload.py
+++ b/tools/testing/selftests/bpf/test_offload.py
@@ -20,6 +20,7 @@ import os
 import pprint
 import random
 import string
+import struct
 import subprocess
 import time
 
@@ -156,6 +157,14 @@ def bpftool_prog_list(expected=None, ns=""):
                  (len(progs), expected))
     return progs
 
+def bpftool_map_list(expected=None, ns=""):
+    _, maps = bpftool("map show", JSON=True, ns=ns, fail=True)
+    if expected is not None:
+        if len(maps) != expected:
+            fail(True, "%d BPF maps loaded, expected %d" %
+                 (len(maps), expected))
+    return maps
+
 def bpftool_prog_list_wait(expected=0, n_retry=20):
     for i in range(n_retry):
         nprogs = len(bpftool_prog_list())
@@ -164,6 +173,14 @@ def bpftool_prog_list_wait(expected=0, n_retry=20):
         time.sleep(0.05)
     raise Exception("Time out waiting for program counts to stabilize want %d, have %d" % (expected, nprogs))
 
+def bpftool_map_list_wait(expected=0, n_retry=20):
+    for i in range(n_retry):
+        nmaps = len(bpftool_map_list())
+        if nmaps == expected:
+            return
+        time.sleep(0.05)
+    raise Exception("Time out waiting for map counts to stabilize want %d, have %d" % (expected, nmaps))
+
 def ip(args, force=False, JSON=True, ns="", fail=True):
     if force:
         args = "-force " + args
@@ -193,6 +210,26 @@ def mknetns(n_retry=10):
             return name
     return None
 
+def int2str(fmt, val):
+    ret = []
+    for b in struct.pack(fmt, val):
+        ret.append(int(b))
+    return " ".join(map(lambda x: str(x), ret))
+
+def str2int(strtab):
+    inttab = []
+    for i in strtab:
+        inttab.append(int(i, 16))
+    ba = bytearray(inttab)
+    if len(strtab) == 4:
+        fmt = "I"
+    elif len(strtab) == 8:
+        fmt = "Q"
+    else:
+        raise Exception("String array of len %d can't be unpacked to an int" %
+                        (len(strtab)))
+    return struct.unpack(fmt, ba)[0]
+
 class DebugfsDir:
     """
     Class for accessing DebugFS directories as a dictionary.
@@ -311,13 +348,13 @@ class NetdevSim:
         return ip("link set dev %s mtu %d" % (self.dev["ifname"], mtu),
                   fail=fail)
 
-    def set_xdp(self, bpf, mode, force=False, fail=True):
+    def set_xdp(self, bpf, mode, force=False, JSON=True, fail=True):
         return ip("link set dev %s xdp%s %s" % (self.dev["ifname"], mode, bpf),
-                  force=force, fail=fail)
+                  force=force, JSON=JSON, fail=fail)
 
-    def unset_xdp(self, mode, force=False, fail=True):
+    def unset_xdp(self, mode, force=False, JSON=True, fail=True):
         return ip("link set dev %s xdp%s off" % (self.dev["ifname"], mode),
-                  force=force, fail=fail)
+                  force=force, JSON=JSON, fail=fail)
 
     def ip_link_show(self, xdp):
         _, link = ip("link show dev %s" % (self['ifname']))
@@ -390,12 +427,16 @@ class NetdevSim:
 
 ################################################################################
 def clean_up():
+    global files, netns, devs
+
     for dev in devs:
         dev.remove()
     for f in files:
         cmd("rm -f %s" % (f))
     for ns in netns:
         cmd("ip netns delete %s" % (ns))
+    files = []
+    netns = []
 
 def pin_prog(file_name, idx=0):
     progs = bpftool_prog_list(expected=(idx + 1))
@@ -405,16 +446,31 @@ def pin_prog(file_name, idx=0):
 
     return file_name, bpf_pinned(file_name)
 
-def check_dev_info(other_ns, ns, pin_file=None, removed=False):
-    if removed:
-        bpftool_prog_list(expected=0)
-        ret, err = bpftool("prog show pin %s" % (pin_file), fail=False)
-        fail(ret == 0, "Showing prog with removed device did not fail")
-        fail(err["error"].find("No such device") == -1,
-             "Showing prog with removed device expected ENODEV, error is %s" %
-             (err["error"]))
-        return
-    progs = bpftool_prog_list(expected=int(not removed), ns=ns)
+def pin_map(file_name, idx=0, expected=1):
+    maps = bpftool_map_list(expected=expected)
+    m = maps[idx]
+    bpftool("map pin id %d %s" % (m["id"], file_name))
+    files.append(file_name)
+
+    return file_name, bpf_pinned(file_name)
+
+def check_dev_info_removed(prog_file=None, map_file=None):
+    bpftool_prog_list(expected=0)
+    ret, err = bpftool("prog show pin %s" % (prog_file), fail=False)
+    fail(ret == 0, "Showing prog with removed device did not fail")
+    fail(err["error"].find("No such device") == -1,
+         "Showing prog with removed device expected ENODEV, error is %s" %
+         (err["error"]))
+
+    bpftool_map_list(expected=0)
+    ret, err = bpftool("map show pin %s" % (map_file), fail=False)
+    fail(ret == 0, "Showing map with removed device did not fail")
+    fail(err["error"].find("No such device") == -1,
+         "Showing map with removed device expected ENODEV, error is %s" %
+         (err["error"]))
+
+def check_dev_info(other_ns, ns, prog_file=None, map_file=None, removed=False):
+    progs = bpftool_prog_list(expected=1, ns=ns)
     prog = progs[0]
 
     fail("dev" not in prog.keys(), "Device parameters not reported")
@@ -423,16 +479,17 @@ def check_dev_info(other_ns, ns, pin_file=None, removed=False):
     fail("ns_dev" not in dev.keys(), "Device parameters not reported")
     fail("ns_inode" not in dev.keys(), "Device parameters not reported")
 
-    if not removed and not other_ns:
+    if not other_ns:
         fail("ifname" not in dev.keys(), "Ifname not reported")
         fail(dev["ifname"] != sim["ifname"],
              "Ifname incorrect %s vs %s" % (dev["ifname"], sim["ifname"]))
     else:
         fail("ifname" in dev.keys(), "Ifname is reported for other ns")
-        if removed:
-            fail(dev["ifindex"] != 0, "Device perameters not zero on removed")
-            fail(dev["ns_dev"] != 0, "Device perameters not zero on removed")
-            fail(dev["ns_inode"] != 0, "Device perameters not zero on removed")
+
+    maps = bpftool_map_list(expected=2, ns=ns)
+    for m in maps:
+        fail("dev" not in m.keys(), "Device parameters not reported")
+        fail(dev != m["dev"], "Map's device different than program's")
 
 # Parse command line
 parser = argparse.ArgumentParser()
@@ -464,7 +521,7 @@ if out.find("/sys/kernel/debug type debugfs") == -1:
     cmd("mount -t debugfs none /sys/kernel/debug")
 
 # Check samples are compiled
-samples = ["sample_ret0.o"]
+samples = ["sample_ret0.o", "sample_map_ret0.o"]
 for s in samples:
     ret, out = cmd("ls %s/%s" % (bpf_test_dir, s), fail=False)
     skip(ret != 0, "sample %s/%s not found, please compile it" %
@@ -739,8 +796,9 @@ try:
     bpftool_prog_list_wait(expected=0)
 
     sim = NetdevSim()
-    sim.set_ethtool_tc_offloads(True)
-    sim.set_xdp(obj, "offload")
+    map_obj = bpf_obj("sample_map_ret0.o")
+    start_test("Test loading program with maps...")
+    sim.set_xdp(map_obj, "offload", JSON=False) # map fixup msg breaks JSON
 
     start_test("Test bpftool bound info reporting (own ns)...")
     check_dev_info(False, "")
@@ -757,11 +815,111 @@ try:
     sim.set_ns("")
     check_dev_info(False, "")
 
-    pin_file, _ = pin_prog("/sys/fs/bpf/tmp")
+    prog_file, _ = pin_prog("/sys/fs/bpf/tmp_prog")
+    map_file, _ = pin_map("/sys/fs/bpf/tmp_map", idx=1, expected=2)
     sim.remove()
 
     start_test("Test bpftool bound info reporting (removed dev)...")
-    check_dev_info(True, "", pin_file=pin_file, removed=True)
+    check_dev_info_removed(prog_file=prog_file, map_file=map_file)
+
+    # Remove all pinned files and reinstantiate the netdev
+    clean_up()
+    bpftool_prog_list_wait(expected=0)
+
+    sim = NetdevSim()
+
+    start_test("Test map update (no flags)...")
+    sim.set_xdp(map_obj, "offload", JSON=False) # map fixup msg breaks JSON
+    maps = bpftool_map_list(expected=2)
+    array = maps[0] if maps[0]["type"] == "array" else maps[1]
+    htab = maps[0] if maps[0]["type"] == "hash" else maps[1]
+    for m in maps:
+        for i in range(2):
+            bpftool("map update id %d key %s value %s" %
+                    (m["id"], int2str("I", i), int2str("Q", i * 3)))
+
+    for m in maps:
+        ret, _ = bpftool("map update id %d key %s value %s" %
+                         (m["id"], int2str("I", 3), int2str("Q", 3 * 3)),
+                         fail=False)
+        fail(ret == 0, "added too many entries")
+
+    start_test("Test map update (exists)...")
+    for m in maps:
+        for i in range(2):
+            bpftool("map update id %d key %s value %s exist" %
+                    (m["id"], int2str("I", i), int2str("Q", i * 3)))
+
+    for m in maps:
+        ret, err = bpftool("map update id %d key %s value %s exist" %
+                           (m["id"], int2str("I", 3), int2str("Q", 3 * 3)),
+                           fail=False)
+        fail(ret == 0, "updated non-existing key")
+        fail(err["error"].find("No such file or directory") == -1,
+             "expected ENOENT, error is '%s'" % (err["error"]))
+
+    start_test("Test map update (noexist)...")
+    for m in maps:
+        for i in range(2):
+            ret, err = bpftool("map update id %d key %s value %s noexist" %
+                               (m["id"], int2str("I", i), int2str("Q", i * 3)),
+                               fail=False)
+        fail(ret == 0, "updated existing key")
+        fail(err["error"].find("File exists") == -1,
+             "expected EEXIST, error is '%s'" % (err["error"]))
+
+    start_test("Test map dump...")
+    for m in maps:
+        _, entries = bpftool("map dump id %d" % (m["id"]))
+        for i in range(2):
+            key = str2int(entries[i]["key"])
+            fail(key != i, "expected key %d, got %d" % (key, i))
+            val = str2int(entries[i]["value"])
+            fail(val != i * 3, "expected value %d, got %d" % (val, i * 3))
+
+    start_test("Test map getnext...")
+    for m in maps:
+        _, entry = bpftool("map getnext id %d" % (m["id"]))
+        key = str2int(entry["next_key"])
+        fail(key != 0, "next key %d, expected %d" % (key, 0))
+        _, entry = bpftool("map getnext id %d key %s" %
+                           (m["id"], int2str("I", 0)))
+        key = str2int(entry["next_key"])
+        fail(key != 1, "next key %d, expected %d" % (key, 1))
+        ret, err = bpftool("map getnext id %d key %s" %
+                           (m["id"], int2str("I", 1)), fail=False)
+        fail(ret == 0, "got next key past the end of map")
+        fail(err["error"].find("No such file or directory") == -1,
+             "expected ENOENT, error is '%s'" % (err["error"]))
+
+    start_test("Test map delete (htab)...")
+    for i in range(2):
+        bpftool("map delete id %d key %s" % (htab["id"], int2str("I", i)))
+
+    start_test("Test map delete (array)...")
+    for i in range(2):
+        ret, err = bpftool("map delete id %d key %s" %
+                           (htab["id"], int2str("I", i)), fail=False)
+        fail(ret == 0, "removed entry from an array")
+        fail(err["error"].find("No such file or directory") == -1,
+             "expected ENOENT, error is '%s'" % (err["error"]))
+
+    start_test("Test map remove...")
+    sim.unset_xdp("offload")
+    bpftool_map_list_wait(expected=0)
+    sim.remove()
+
+    sim = NetdevSim()
+    sim.set_xdp(map_obj, "offload", JSON=False) # map fixup msg breaks JSON
+    sim.remove()
+    bpftool_map_list_wait(expected=0)
+
+    start_test("Test map creation fail path...")
+    sim = NetdevSim()
+    sim.dfs["bpf_map_accept"] = "N"
+    ret, _ = sim.set_xdp(map_obj, "offload", JSON=False, fail=False)
+    fail(ret == 0,
+         "netdevsim didn't refuse to create a map with offload disabled")
 
     print("%s: OK" % (os.path.basename(__file__)))