[PATCH iproute2-next v2 00/11] Add a tool for configuration of DCB

[PATCH iproute2-next v2 00/11] Add a tool for configuration of DCB

[Petr Machata]

The Linux DCB interface allows configuration of a broad range of
hardware-specific attributes, such as TC scheduling, flow control, per-port
buffer configuration, TC rate, etc.

Currently a common libre tool for configuration of DCB is OpenLLDP. This
suite contains a daemon that uses Linux DCB interface to configure HW
according to the DCB TLVs exchanged over an interface. The daemon can also
be controlled by a client, through which the user can adjust and view the
configuration. The downside of using OpenLLDP is that it is somewhat
heavyweight and difficult to use in scripts, and does not support
extensions such as buffer and rate commands.

For access to many HW features, one would be perfectly fine with a
fire-and-forget tool along the lines of "ip" or "tc". For scripting in
particular, this would be ideal. This author is aware of one such tool,
mlnx_qos from Mellanox OFED scripts collection[1].

The downside here is that the tool is very verbose, the command line
language is awkward to use, it is not packaged in Linux distros, and
generally has the appearance of a very vendor-specific tool, despite not
being one.

This patchset addresses the above issues by providing a seed of a clean,
well-documented, easily usable, extensible fire-and-forget tool for DCB
configuration:

    # dcb ets set dev eni1np1 \
                  tc-tsa all:strict 0:ets 1:ets 2:ets \
		  tc-bw all:0 0:33 1:33 2:34

    # dcb ets show dev eni1np1 tc-tsa tc-bw
    tc-tsa 0:ets 1:ets 2:ets 3:strict 4:strict 5:strict 6:strict 7:strict
    tc-bw 0:33 1:33 2:34 3:0 4:0 5:0 6:0 7:0

    # dcb ets set dev eni1np1 tc-bw 1:30 2:37

    # dcb -j ets show dev eni1np1 | jq '.tc_bw[2]'
    37

The patchset proceeds as follows:

- Many tools in iproute2 have an option to work in batch mode, where the
  commands to run are given in a file. The code to handle batching is
  largely the same independent of the tool in question. In patch #1, add a
  helper to handle the batching, and migrate individual tools to use it.

- A number of configuration options come in a form of an on-off switch.
  This in turn can be considered a special case of parsing one of a given
  set of strings. In patch #2, extract helpers to parse one of a number of
  strings, on top of which build an on-off parser.

  Currently each tool open-codes the logic to parse the on-off toggle. A
  future patch set will migrate instances of this code over to the new
  helpers.

- The on/off toggles from previous list item sometimes need to be dumped.
  While in the FP output, one typically wishes to maintain consistency with
  the command line and show actual strings, "on" and "off", in JSON output
  one would rather use booleans. This logic is somewhat annoying to have to
  open-code time and again. Therefore in patch #3, add a helper to do just
  that.

- The DCB tool is built on top of libmnl. Several routines will be
  basically the same in DCB as they are currently in devlink. In patches
  #4-#6, extract them to a new module, mnl_utils, for easy reuse.

- Much of DCB is built around arrays. A syntax similar to the iplink_vlan's
  ingress-qos-map / egress-qos-map is very handy for describing changes
  done to such arrays. Therefore in patch #7, extract a helper,
  parse_mapping(), which manages parsing of key-value arrays. In patch #8,
  fix a buglet in the helper, and in patch #9, extend it to allow setting
  of all array elements in one go.

- In patch #10, add a skeleton of "dcb", which contains common helpers and
  dispatches to subtools for handling of individual objects. The skeleton
  is empty as of this patch.

  In patch #11, add "dcb_ets", a module for handling of specifically DCB
  ETS objects.

  The intention is to gradually add handlers for at least PFC, APP, peer
  configuration, buffers and rates.

[1] https://github.com/Mellanox/mlnx-tools/tree/master/ofed_scripts

v2:
- A new function, print_on_off_bool(), has been introduced for showing
  on-off toggles in both FP and JSON modes.
  [Jakub Kicinski, Stephen Hemminger]

- This prompted refactoring in several existing files, and pushed the
  number of patches in the set too high. The cleanup patches have therefore
  been moved out to another patchset, which will follow after this one.

- When dumping JSON, format keys so that they are valid jq identifiers.
  E.g. "tc_tsa" instead of "tc-tsa". Additionally, do not dump arrays as
  objects with string indices, but as true arrays. This allows for more
  natural access to individual items, e.g.:
    # dcb ets -j show dev eth0 | jq '.tc_tsa[3]'
  Instead of:
    # dcb ets -j show dev eth0 | jq '.["tc-tsa"]["3"]'

- Patch #4:
  - Add SPDX-License-Identifier

- Patch #7:
  - In parse_qos_mapping(), propagate return value from addattr_l()
    [Roman Mashak]

Petr Machata (11):
  Unify batch processing across tools
  lib: Add parse_one_of(), parse_on_off()
  lib: utils: Add print_on_off_bool()
  lib: Extract from devlink/mnlg a helper, mnlu_socket_open()
  lib: Extract from devlink/mnlg a helper, mnlu_msg_prepare()
  lib: Extract from devlink/mnlg a helper, mnlu_socket_recv_run()
  lib: Extract from iplink_vlan a helper to parse key:value arrays
  lib: parse_mapping: Update argc, argv on error
  lib: parse_mapping: Recognize a keyword "all"
  Add skeleton of a new tool, dcb
  dcb: Add a subtool for the DCB ETS object

 Makefile            |   2 +-
 bridge/bridge.c     |  38 +---
 dcb/Makefile        |  24 +++
 dcb/dcb.c           | 403 +++++++++++++++++++++++++++++++++++++++++
 dcb/dcb.h           |  39 ++++
 dcb/dcb_ets.c       | 430 ++++++++++++++++++++++++++++++++++++++++++++
 devlink/Makefile    |   2 +-
 devlink/devlink.c   |  41 +----
 devlink/mnlg.c      |  93 ++--------
 include/mnl_utils.h |  11 ++
 include/utils.h     |  12 ++
 ip/ip.c             |  46 ++---
 ip/iplink_vlan.c    |  36 ++--
 ip/ipmacsec.c       |  52 ++----
 lib/Makefile        |   2 +-
 lib/mnl_utils.c     | 110 ++++++++++++
 lib/utils.c         | 111 ++++++++++++
 man/man8/dcb-ets.8  | 185 +++++++++++++++++++
 man/man8/dcb.8      | 114 ++++++++++++
 rdma/rdma.c         |  38 +---
 tc/tc.c             |  38 +---
 21 files changed, 1518 insertions(+), 309 deletions(-)
 create mode 100644 dcb/Makefile
 create mode 100644 dcb/dcb.c
 create mode 100644 dcb/dcb.h
 create mode 100644 dcb/dcb_ets.c
 create mode 100644 include/mnl_utils.h
 create mode 100644 lib/mnl_utils.c
 create mode 100644 man/man8/dcb-ets.8
 create mode 100644 man/man8/dcb.8

-- 
2.25.1

[PATCH iproute2-next v2 01/11] Unify batch processing across tools

[Petr Machata]

The code for handling batches is largely the same across iproute2 tools.
Extract a helper to handle the batch, and adjust the tools to dispatch to
this helper. Sandwitch the invocation between prologue / epilogue code
specific for each tool.

Signed-off-by: Petr Machata <me@pmachata.org>
---
 bridge/bridge.c   | 38 +++++++-------------------------------
 devlink/devlink.c | 41 +++++++----------------------------------
 include/utils.h   |  3 +++
 ip/ip.c           | 46 ++++++++++------------------------------------
 lib/utils.c       | 40 ++++++++++++++++++++++++++++++++++++++++
 rdma/rdma.c       | 38 +++++++-------------------------------
 tc/tc.c           | 38 +++++++-------------------------------
 7 files changed, 81 insertions(+), 163 deletions(-)

diff --git a/bridge/bridge.c b/bridge/bridge.c
index 453d689732bd..8f691cfdd466 100644
--- a/bridge/bridge.c
+++ b/bridge/bridge.c
@@ -77,20 +77,14 @@ static int do_cmd(const char *argv0, int argc, char **argv)
 	return -1;
 }
 
-static int batch(const char *name)
+static int br_batch_cmd(int argc, char *argv[], void *data)
 {
-	char *line = NULL;
-	size_t len = 0;
-	int ret = EXIT_SUCCESS;
+	return do_cmd(argv[0], argc, argv);
+}
 
-	if (name && strcmp(name, "-") != 0) {
-		if (freopen(name, "r", stdin) == NULL) {
-			fprintf(stderr,
-				"Cannot open file \"%s\" for reading: %s\n",
-				name, strerror(errno));
-			return EXIT_FAILURE;
-		}
-	}
+static int batch(const char *name)
+{
+	int ret;
 
 	if (rtnl_open(&rth, 0) < 0) {
 		fprintf(stderr, "Cannot open rtnetlink\n");
@@ -99,25 +93,7 @@ static int batch(const char *name)
 
 	rtnl_set_strict_dump(&rth);
 
-	cmdlineno = 0;
-	while (getcmdline(&line, &len, stdin) != -1) {
-		char *largv[100];
-		int largc;
-
-		largc = makeargs(line, largv, 100);
-		if (largc == 0)
-			continue;       /* blank line */
-
-		if (do_cmd(largv[0], largc, largv)) {
-			fprintf(stderr, "Command failed %s:%d\n",
-				name, cmdlineno);
-			ret = EXIT_FAILURE;
-			if (!force)
-				break;
-		}
-	}
-	if (line)
-		free(line);
+	ret = do_batch(name, force, br_batch_cmd, NULL);
 
 	rtnl_close(&rth);
 	return ret;
diff --git a/devlink/devlink.c b/devlink/devlink.c
index 007677a5c564..7dba42c602b3 100644
--- a/devlink/devlink.c
+++ b/devlink/devlink.c
@@ -7745,43 +7745,16 @@ static void dl_free(struct dl *dl)
 	free(dl);
 }
 
-static int dl_batch(struct dl *dl, const char *name, bool force)
+static int dl_batch_cmd(int argc, char *argv[], void *data)
 {
-	char *line = NULL;
-	size_t len = 0;
-	int ret = EXIT_SUCCESS;
-
-	if (name && strcmp(name, "-") != 0) {
-		if (freopen(name, "r", stdin) == NULL) {
-			fprintf(stderr,
-				"Cannot open file \"%s\" for reading: %s\n",
-				name, strerror(errno));
-			return EXIT_FAILURE;
-		}
-	}
-
-	cmdlineno = 0;
-	while (getcmdline(&line, &len, stdin) != -1) {
-		char *largv[100];
-		int largc;
-
-		largc = makeargs(line, largv, 100);
-		if (!largc)
-			continue;	/* blank line */
-
-		if (dl_cmd(dl, largc, largv)) {
-			fprintf(stderr, "Command failed %s:%d\n",
-				name, cmdlineno);
-			ret = EXIT_FAILURE;
-			if (!force)
-				break;
-		}
-	}
+	struct dl *dl = data;
 
-	if (line)
-		free(line);
+	return dl_cmd(dl, argc, argv);
+}
 
-	return ret;
+static int dl_batch(struct dl *dl, const char *name, bool force)
+{
+	return do_batch(name, force, dl_batch_cmd, dl);
 }
 
 int main(int argc, char **argv)
diff --git a/include/utils.h b/include/utils.h
index 7041c4612e46..085b17b1f6e3 100644
--- a/include/utils.h
+++ b/include/utils.h
@@ -322,4 +322,7 @@ int get_time64(__s64 *time, const char *str);
 char *sprint_time(__u32 time, char *buf);
 char *sprint_time64(__s64 time, char *buf);
 
+int do_batch(const char *name, bool force,
+	     int (*cmd)(int argc, char *argv[], void *user), void *user);
+
 #endif /* __UTILS_H__ */
diff --git a/ip/ip.c b/ip/ip.c
index ac4450235370..5e31957f2420 100644
--- a/ip/ip.c
+++ b/ip/ip.c
@@ -121,56 +121,30 @@ static int do_cmd(const char *argv0, int argc, char **argv)
 	return EXIT_FAILURE;
 }
 
-static int batch(const char *name)
+static int ip_batch_cmd(int argc, char *argv[], void *data)
 {
-	char *line = NULL;
-	size_t len = 0;
-	int ret = EXIT_SUCCESS;
-	int orig_family = preferred_family;
+	const int *orig_family = data;
 
-	batch_mode = 1;
+	preferred_family = *orig_family;
+	return do_cmd(argv[0], argc, argv);
+}
 
-	if (name && strcmp(name, "-") != 0) {
-		if (freopen(name, "r", stdin) == NULL) {
-			fprintf(stderr,
-				"Cannot open file \"%s\" for reading: %s\n",
-				name, strerror(errno));
-			return EXIT_FAILURE;
-		}
-	}
+static int batch(const char *name)
+{
+	int orig_family = preferred_family;
+	int ret;
 
 	if (rtnl_open(&rth, 0) < 0) {
 		fprintf(stderr, "Cannot open rtnetlink\n");
 		return EXIT_FAILURE;
 	}
 
-	cmdlineno = 0;
-	while (getcmdline(&line, &len, stdin) != -1) {
-		char *largv[100];
-		int largc;
-
-		preferred_family = orig_family;
-
-		largc = makeargs(line, largv, 100);
-		if (largc == 0)
-			continue;	/* blank line */
-
-		if (do_cmd(largv[0], largc, largv)) {
-			fprintf(stderr, "Command failed %s:%d\n",
-				name, cmdlineno);
-			ret = EXIT_FAILURE;
-			if (!force)
-				break;
-		}
-	}
-	if (line)
-		free(line);
+	ret = do_batch(name, force, ip_batch_cmd, &orig_family);
 
 	rtnl_close(&rth);
 	return ret;
 }
 
-
 int main(int argc, char **argv)
 {
 	char *basename;
diff --git a/lib/utils.c b/lib/utils.c
index c98021d6ecad..9815e328c9e0 100644
--- a/lib/utils.c
+++ b/lib/utils.c
@@ -1695,3 +1695,43 @@ char *sprint_time64(__s64 time, char *buf)
 	print_time64(buf, SPRINT_BSIZE-1, time);
 	return buf;
 }
+
+int do_batch(const char *name, bool force,
+	     int (*cmd)(int argc, char *argv[], void *data), void *data)
+{
+	char *line = NULL;
+	size_t len = 0;
+	int ret = EXIT_SUCCESS;
+
+	if (name && strcmp(name, "-") != 0) {
+		if (freopen(name, "r", stdin) == NULL) {
+			fprintf(stderr,
+				"Cannot open file \"%s\" for reading: %s\n",
+				name, strerror(errno));
+			return EXIT_FAILURE;
+		}
+	}
+
+	cmdlineno = 0;
+	while (getcmdline(&line, &len, stdin) != -1) {
+		char *largv[100];
+		int largc;
+
+		largc = makeargs(line, largv, 100);
+		if (!largc)
+			continue;	/* blank line */
+
+		if (cmd(largc, largv, data)) {
+			fprintf(stderr, "Command failed %s:%d\n",
+				name, cmdlineno);
+			ret = EXIT_FAILURE;
+			if (!force)
+				break;
+		}
+	}
+
+	if (line)
+		free(line);
+
+	return ret;
+}
diff --git a/rdma/rdma.c b/rdma/rdma.c
index 9ea2d17ffe9e..8dc2d3e344be 100644
--- a/rdma/rdma.c
+++ b/rdma/rdma.c
@@ -41,40 +41,16 @@ static int rd_cmd(struct rd *rd, int argc, char **argv)
 	return rd_exec_cmd(rd, cmds, "object");
 }
 
-static int rd_batch(struct rd *rd, const char *name, bool force)
+static int rd_batch_cmd(int argc, char *argv[], void *data)
 {
-	char *line = NULL;
-	size_t len = 0;
-	int ret = 0;
-
-	if (name && strcmp(name, "-") != 0) {
-		if (!freopen(name, "r", stdin)) {
-			pr_err("Cannot open file \"%s\" for reading: %s\n",
-			       name, strerror(errno));
-			return errno;
-		}
-	}
+	struct rd *rd = data;
 
-	cmdlineno = 0;
-	while (getcmdline(&line, &len, stdin) != -1) {
-		char *largv[512];
-		int largc;
-
-		largc = makeargs(line, largv, ARRAY_SIZE(largv));
-		if (!largc)
-			continue;	/* blank line */
-
-		ret = rd_cmd(rd, largc, largv);
-		if (ret) {
-			pr_err("Command failed %s:%d\n", name, cmdlineno);
-			if (!force)
-				break;
-		}
-	}
-
-	free(line);
+	return rd_cmd(rd, argc, argv);
+}
 
-	return ret;
+static int rd_batch(struct rd *rd, const char *name, bool force)
+{
+	return do_batch(name, force, rd_batch_cmd, rd);
 }
 
 static int rd_init(struct rd *rd, char *filename)
diff --git a/tc/tc.c b/tc/tc.c
index 5d57054b45fb..01fe58d06202 100644
--- a/tc/tc.c
+++ b/tc/tc.c
@@ -231,22 +231,16 @@ static int do_cmd(int argc, char **argv)
 	return -1;
 }
 
+static int tc_batch_cmd(int argc, char *argv[], void *data)
+{
+	return do_cmd(argc, argv);
+}
+
 static int batch(const char *name)
 {
-	char *line = NULL;
-	size_t len = 0;
-	int ret = 0;
+	int ret;
 
 	batch_mode = 1;
-	if (name && strcmp(name, "-") != 0) {
-		if (freopen(name, "r", stdin) == NULL) {
-			fprintf(stderr,
-				"Cannot open file \"%s\" for reading: %s\n",
-				name, strerror(errno));
-			return -1;
-		}
-	}
-
 	tc_core_init();
 
 	if (rtnl_open(&rth, 0) < 0) {
@@ -254,26 +248,8 @@ static int batch(const char *name)
 		return -1;
 	}
 
-	cmdlineno = 0;
-	while (getcmdline(&line, &len, stdin) != -1) {
-		char *largv[100];
-		int largc;
-
-		largc = makeargs(line, largv, 100);
-		if (largc == 0)
-			continue;	/* blank line */
-
-		if (do_cmd(largc, largv)) {
-			fprintf(stderr, "Command failed %s:%d\n",
-				name, cmdlineno);
-			ret = 1;
-			if (!force)
-				break;
-		}
-		fflush(stdout);
-	}
+	ret = do_batch(name, force, tc_batch_cmd, NULL);
 
-	free(line);
 	rtnl_close(&rth);
 	return ret;
 }
-- 
2.25.1

[PATCH iproute2-next v2 02/11] lib: Add parse_one_of(), parse_on_off()

[Petr Machata]

Take from the macsec code parse_one_of() and adapt so that it passes the
primary result as the main return value, and error result through a
pointer. That is the simplest way to make the code reusable across data
types without introducing extra magic.

Also from macsec take the specialization of parse_one_of() for parsing
specifically the strings "off" and "on".

Convert the macsec code to the new helpers.

Signed-off-by: Petr Machata <me@pmachata.org>
---
 include/utils.h |  4 ++++
 ip/ipmacsec.c   | 52 +++++++++++--------------------------------------
 lib/utils.c     | 28 ++++++++++++++++++++++++++
 3 files changed, 43 insertions(+), 41 deletions(-)

diff --git a/include/utils.h b/include/utils.h
index 085b17b1f6e3..bd62cdcd7122 100644
--- a/include/utils.h
+++ b/include/utils.h
@@ -325,4 +325,8 @@ char *sprint_time64(__s64 time, char *buf);
 int do_batch(const char *name, bool force,
 	     int (*cmd)(int argc, char *argv[], void *user), void *user);
 
+int parse_one_of(const char *msg, const char *realval, const char * const *list,
+		 size_t len, int *p_err);
+int parse_on_off(const char *msg, const char *realval, int *p_err);
+
 #endif /* __UTILS_H__ */
diff --git a/ip/ipmacsec.c b/ip/ipmacsec.c
index 18289ecd6d9e..bf48e8b5d0b2 100644
--- a/ip/ipmacsec.c
+++ b/ip/ipmacsec.c
@@ -23,8 +23,6 @@
 #include "ll_map.h"
 #include "libgenl.h"
 
-static const char * const values_on_off[] = { "off", "on" };
-
 static const char * const validate_str[] = {
 	[MACSEC_VALIDATE_DISABLED] = "disabled",
 	[MACSEC_VALIDATE_CHECK] = "check",
@@ -108,25 +106,6 @@ static void ipmacsec_usage(void)
 	exit(-1);
 }
 
-static int one_of(const char *msg, const char *realval, const char * const *list,
-		  size_t len, int *index)
-{
-	int i;
-
-	for (i = 0; i < len; i++) {
-		if (matches(realval, list[i]) == 0) {
-			*index = i;
-			return 0;
-		}
-	}
-
-	fprintf(stderr, "Error: argument of \"%s\" must be one of ", msg);
-	for (i = 0; i < len; i++)
-		fprintf(stderr, "\"%s\", ", list[i]);
-	fprintf(stderr, "not \"%s\"\n", realval);
-	return -1;
-}
-
 static int get_an(__u8 *val, const char *arg)
 {
 	int ret = get_u8(val, arg, 0);
@@ -559,8 +538,7 @@ static int do_offload(enum cmd c, int argc, char **argv)
 	if (argc == 0)
 		ipmacsec_usage();
 
-	ret = one_of("offload", *argv, offload_str, ARRAY_SIZE(offload_str),
-		     (int *)&offload);
+	offload = parse_one_of("offload", *argv, offload_str, ARRAY_SIZE(offload_str), &ret);
 	if (ret)
 		ipmacsec_usage();
 
@@ -1334,8 +1312,7 @@ static int macsec_parse_opt(struct link_util *lu, int argc, char **argv,
 			NEXT_ARG();
 			int i;
 
-			ret = one_of("encrypt", *argv, values_on_off,
-				     ARRAY_SIZE(values_on_off), &i);
+			i = parse_on_off("encrypt", *argv, &ret);
 			if (ret != 0)
 				return ret;
 			addattr8(n, MACSEC_BUFLEN, IFLA_MACSEC_ENCRYPT, i);
@@ -1343,8 +1320,7 @@ static int macsec_parse_opt(struct link_util *lu, int argc, char **argv,
 			NEXT_ARG();
 			int i;
 
-			ret = one_of("send_sci", *argv, values_on_off,
-				     ARRAY_SIZE(values_on_off), &i);
+			i = parse_on_off("send_sci", *argv, &ret);
 			if (ret != 0)
 				return ret;
 			send_sci = i;
@@ -1354,8 +1330,7 @@ static int macsec_parse_opt(struct link_util *lu, int argc, char **argv,
 			NEXT_ARG();
 			int i;
 
-			ret = one_of("end_station", *argv, values_on_off,
-				     ARRAY_SIZE(values_on_off), &i);
+			i = parse_on_off("end_station", *argv, &ret);
 			if (ret != 0)
 				return ret;
 			es = i;
@@ -1364,8 +1339,7 @@ static int macsec_parse_opt(struct link_util *lu, int argc, char **argv,
 			NEXT_ARG();
 			int i;
 
-			ret = one_of("scb", *argv, values_on_off,
-				     ARRAY_SIZE(values_on_off), &i);
+			i = parse_on_off("scb", *argv, &ret);
 			if (ret != 0)
 				return ret;
 			scb = i;
@@ -1374,8 +1348,7 @@ static int macsec_parse_opt(struct link_util *lu, int argc, char **argv,
 			NEXT_ARG();
 			int i;
 
-			ret = one_of("protect", *argv, values_on_off,
-				     ARRAY_SIZE(values_on_off), &i);
+			i = parse_on_off("protect", *argv, &ret);
 			if (ret != 0)
 				return ret;
 			addattr8(n, MACSEC_BUFLEN, IFLA_MACSEC_PROTECT, i);
@@ -1383,8 +1356,7 @@ static int macsec_parse_opt(struct link_util *lu, int argc, char **argv,
 			NEXT_ARG();
 			int i;
 
-			ret = one_of("replay", *argv, values_on_off,
-				     ARRAY_SIZE(values_on_off), &i);
+			i = parse_on_off("replay", *argv, &ret);
 			if (ret != 0)
 				return ret;
 			replay_protect = !!i;
@@ -1395,9 +1367,8 @@ static int macsec_parse_opt(struct link_util *lu, int argc, char **argv,
 				invarg("expected replay window size", *argv);
 		} else if (strcmp(*argv, "validate") == 0) {
 			NEXT_ARG();
-			ret = one_of("validate", *argv,
-				     validate_str, ARRAY_SIZE(validate_str),
-				     (int *)&validate);
+			validate = parse_one_of("validate", *argv, validate_str,
+						ARRAY_SIZE(validate_str), &ret);
 			if (ret != 0)
 				return ret;
 			addattr8(n, MACSEC_BUFLEN,
@@ -1411,9 +1382,8 @@ static int macsec_parse_opt(struct link_util *lu, int argc, char **argv,
 				invarg("expected an { 0..3 }", *argv);
 		} else if (strcmp(*argv, "offload") == 0) {
 			NEXT_ARG();
-			ret = one_of("offload", *argv,
-				     offload_str, ARRAY_SIZE(offload_str),
-				     (int *)&offload);
+			offload = parse_one_of("offload", *argv, offload_str,
+					       ARRAY_SIZE(offload_str), &ret);
 			if (ret != 0)
 				return ret;
 			addattr8(n, MACSEC_BUFLEN,
diff --git a/lib/utils.c b/lib/utils.c
index 9815e328c9e0..930877ae0f0d 100644
--- a/lib/utils.c
+++ b/lib/utils.c
@@ -1735,3 +1735,31 @@ int do_batch(const char *name, bool force,
 
 	return ret;
 }
+
+int parse_one_of(const char *msg, const char *realval, const char * const *list,
+		 size_t len, int *p_err)
+{
+	int i;
+
+	for (i = 0; i < len; i++) {
+		if (list[i] && matches(realval, list[i]) == 0) {
+			*p_err = 0;
+			return i;
+		}
+	}
+
+	fprintf(stderr, "Error: argument of \"%s\" must be one of ", msg);
+	for (i = 0; i < len; i++)
+		if (list[i])
+			fprintf(stderr, "\"%s\", ", list[i]);
+	fprintf(stderr, "not \"%s\"\n", realval);
+	*p_err = -EINVAL;
+	return 0;
+}
+
+int parse_on_off(const char *msg, const char *realval, int *p_err)
+{
+	static const char * const values_on_off[] = { "off", "on" };
+
+	return parse_one_of(msg, realval, values_on_off, ARRAY_SIZE(values_on_off), p_err);
+}
-- 
2.25.1

Re: [PATCH iproute2-next v2 02/11] lib: Add parse_one_of(), parse_on_off()

[David Ahern]

On 10/30/20 6:29 AM, Petr Machata wrote:
> diff --git a/lib/utils.c b/lib/utils.c
> index 9815e328c9e0..930877ae0f0d 100644
> --- a/lib/utils.c
> +++ b/lib/utils.c
> @@ -1735,3 +1735,31 @@ int do_batch(const char *name, bool force,
>  
>  	return ret;
>  }
> +
> +int parse_one_of(const char *msg, const char *realval, const char * const *list,
> +		 size_t len, int *p_err)
> +{
> +	int i;
> +
> +	for (i = 0; i < len; i++) {
> +		if (list[i] && matches(realval, list[i]) == 0) {
> +			*p_err = 0;
> +			return i;
> +		}
> +	}
> +
> +	fprintf(stderr, "Error: argument of \"%s\" must be one of ", msg);
> +	for (i = 0; i < len; i++)
> +		if (list[i])
> +			fprintf(stderr, "\"%s\", ", list[i]);
> +	fprintf(stderr, "not \"%s\"\n", realval);
> +	*p_err = -EINVAL;
> +	return 0;
> +}
> +
> +int parse_on_off(const char *msg, const char *realval, int *p_err)
> +{
> +	static const char * const values_on_off[] = { "off", "on" };
> +
> +	return parse_one_of(msg, realval, values_on_off, ARRAY_SIZE(values_on_off), p_err);
> +}
> 

This has weird semantics to me. You have a buried array of strings and
returning the index of the one that matches. Let's use a 'bool' return
for parse_on_off that makes it clear that the string is 'off' = false or
'on' = true.

Re: [PATCH iproute2-next v2 02/11] lib: Add parse_one_of(), parse_on_off()

[Petr Machata]

David Ahern <dsahern@gmail.com> writes:

> On 10/30/20 6:29 AM, Petr Machata wrote:
>> +int parse_on_off(const char *msg, const char *realval, int *p_err)
>> +{
>> +	static const char * const values_on_off[] = { "off", "on" };
>> +
>> +	return parse_one_of(msg, realval, values_on_off, ARRAY_SIZE(values_on_off), p_err);
>> +}
>> 
>
> This has weird semantics to me. You have a buried array of strings and
> returning the index of the one that matches. Let's use a 'bool' return
> for parse_on_off that makes it clear that the string is 'off' = false or
> 'on' = true.

Agreed, it should return bool.

[PATCH iproute2-next v2 03/11] lib: utils: Add print_on_off_bool()

[Petr Machata]

The value of a number of booleans is shown as "on" and "off" in the plain
output, and as an actual boolean in JSON mode. Add a function that does
that.

Signed-off-by: Petr Machata <me@pmachata.org>
---
 include/utils.h | 1 +
 lib/utils.c     | 8 ++++++++
 2 files changed, 9 insertions(+)

diff --git a/include/utils.h b/include/utils.h
index bd62cdcd7122..e3cdb098834a 100644
--- a/include/utils.h
+++ b/include/utils.h
@@ -328,5 +328,6 @@ int do_batch(const char *name, bool force,
 int parse_one_of(const char *msg, const char *realval, const char * const *list,
 		 size_t len, int *p_err);
 int parse_on_off(const char *msg, const char *realval, int *p_err);
+void print_on_off_bool(FILE *fp, const char *flag, bool val);
 
 #endif /* __UTILS_H__ */
diff --git a/lib/utils.c b/lib/utils.c
index 930877ae0f0d..8deec86ecbcd 100644
--- a/lib/utils.c
+++ b/lib/utils.c
@@ -1763,3 +1763,11 @@ int parse_on_off(const char *msg, const char *realval, int *p_err)
 
 	return parse_one_of(msg, realval, values_on_off, ARRAY_SIZE(values_on_off), p_err);
 }
+
+void print_on_off_bool(FILE *fp, const char *flag, bool val)
+{
+	if (is_json_context())
+		print_bool(PRINT_JSON, flag, NULL, val);
+	else
+		fprintf(fp, "%s %s ", flag, val ? "on" : "off");
+}
-- 
2.25.1

Re: [PATCH iproute2-next v2 03/11] lib: utils: Add print_on_off_bool()

[Stephen Hemminger]

On Fri, 30 Oct 2020 13:29:50 +0100
Petr Machata <me@pmachata.org> wrote:

> +void print_on_off_bool(FILE *fp, const char *flag, bool val)
> +{
> +	if (is_json_context())
> +		print_bool(PRINT_JSON, flag, NULL, val);
> +	else
> +		fprintf(fp, "%s %s ", flag, val ? "on" : "off");
> +}

Please use print_string(PRINT_FP for non json case.
I am use fprintf(fp as indicator for code that has not been already
converted to JSON.

And passing the FILE *fp is also indication of old code.
Original iproute2 passed it around but it was always stdout.

Re: [PATCH iproute2-next v2 03/11] lib: utils: Add print_on_off_bool()

[Petr Machata]

Stephen Hemminger <stephen@networkplumber.org> writes:

> On Fri, 30 Oct 2020 13:29:50 +0100
> Petr Machata <me@pmachata.org> wrote:
>
>> +void print_on_off_bool(FILE *fp, const char *flag, bool val)
>> +{
>> +	if (is_json_context())
>> +		print_bool(PRINT_JSON, flag, NULL, val);
>> +	else
>> +		fprintf(fp, "%s %s ", flag, val ? "on" : "off");
>> +}
>
> Please use print_string(PRINT_FP for non json case.
> I am use fprintf(fp as indicator for code that has not been already
> converted to JSON.
>
> And passing the FILE *fp is also indication of old code.
> Original iproute2 passed it around but it was always stdout.

Ack, will fix.

Re: [PATCH iproute2-next v2 03/11] lib: utils: Add print_on_off_bool()

[David Ahern]

On 10/30/20 6:29 AM, Petr Machata wrote:
> diff --git a/include/utils.h b/include/utils.h
> index bd62cdcd7122..e3cdb098834a 100644
> --- a/include/utils.h
> +++ b/include/utils.h
> @@ -328,5 +328,6 @@ int do_batch(const char *name, bool force,
>  int parse_one_of(const char *msg, const char *realval, const char * const *list,
>  		 size_t len, int *p_err);
>  int parse_on_off(const char *msg, const char *realval, int *p_err);
> +void print_on_off_bool(FILE *fp, const char *flag, bool val);
>  
>  #endif /* __UTILS_H__ */
> diff --git a/lib/utils.c b/lib/utils.c
> index 930877ae0f0d..8deec86ecbcd 100644
> --- a/lib/utils.c
> +++ b/lib/utils.c
> @@ -1763,3 +1763,11 @@ int parse_on_off(const char *msg, const char *realval, int *p_err)
>  
>  	return parse_one_of(msg, realval, values_on_off, ARRAY_SIZE(values_on_off), p_err);
>  }
> +
> +void print_on_off_bool(FILE *fp, const char *flag, bool val)
> +{
> +	if (is_json_context())
> +		print_bool(PRINT_JSON, flag, NULL, val);
> +	else
> +		fprintf(fp, "%s %s ", flag, val ? "on" : "off");
> +}
> 

I think print_on_off should be fine and aligns with parse_on_off once it
returns a bool.

Re: [PATCH iproute2-next v2 03/11] lib: utils: Add print_on_off_bool()

[Petr Machata]

David Ahern <dsahern@gmail.com> writes:

> On 10/30/20 6:29 AM, Petr Machata wrote:
>> diff --git a/lib/utils.c b/lib/utils.c
>> index 930877ae0f0d..8deec86ecbcd 100644
>> --- a/lib/utils.c
>> +++ b/lib/utils.c
>> @@ -1763,3 +1763,11 @@ int parse_on_off(const char *msg, const char *realval, int *p_err)
>>
>>  	return parse_one_of(msg, realval, values_on_off, ARRAY_SIZE(values_on_off), p_err);
>>  }
>> +
>> +void print_on_off_bool(FILE *fp, const char *flag, bool val)
>> +{
>> +	if (is_json_context())
>> +		print_bool(PRINT_JSON, flag, NULL, val);
>> +	else
>> +		fprintf(fp, "%s %s ", flag, val ? "on" : "off");
>> +}
>>
>
> I think print_on_off should be fine and aligns with parse_on_off once it
> returns a bool.

print_on_off() is already used in the RDMA tool, and actually outputs
"on" and "off", unlike this. So I chose this instead.

I could rename the RDMA one though -- it's used in two places, whereas
this is used in about two dozen instances across the codebase.

Re: [PATCH iproute2-next v2 03/11] lib: utils: Add print_on_off_bool()

[David Ahern]

On 10/31/20 3:23 PM, Petr Machata wrote:
> 
> David Ahern <dsahern@gmail.com> writes:
> 
>> On 10/30/20 6:29 AM, Petr Machata wrote:
>>> diff --git a/lib/utils.c b/lib/utils.c
>>> index 930877ae0f0d..8deec86ecbcd 100644
>>> --- a/lib/utils.c
>>> +++ b/lib/utils.c
>>> @@ -1763,3 +1763,11 @@ int parse_on_off(const char *msg, const char *realval, int *p_err)
>>>
>>>  	return parse_one_of(msg, realval, values_on_off, ARRAY_SIZE(values_on_off), p_err);
>>>  }
>>> +
>>> +void print_on_off_bool(FILE *fp, const char *flag, bool val)
>>> +{
>>> +	if (is_json_context())
>>> +		print_bool(PRINT_JSON, flag, NULL, val);
>>> +	else
>>> +		fprintf(fp, "%s %s ", flag, val ? "on" : "off");
>>> +}
>>>
>>
>> I think print_on_off should be fine and aligns with parse_on_off once it
>> returns a bool.
> 
> print_on_off() is already used in the RDMA tool, and actually outputs
> "on" and "off", unlike this. So I chose this instead.
> 
> I could rename the RDMA one though -- it's used in two places, whereas
> this is used in about two dozen instances across the codebase.
> 

yes, the rdma utils are using generic function names. The rdma version
should be renamed; perhaps rd_print_on_off. That seems to be once common
prefix. Added Leon.

Re: [PATCH iproute2-next v2 03/11] lib: utils: Add print_on_off_bool()

[Leon Romanovsky]

On Sun, Nov 01, 2020 at 04:55:42PM -0700, David Ahern wrote:
> On 10/31/20 3:23 PM, Petr Machata wrote:
> >
> > David Ahern <dsahern@gmail.com> writes:
> >
> >> On 10/30/20 6:29 AM, Petr Machata wrote:
> >>> diff --git a/lib/utils.c b/lib/utils.c
> >>> index 930877ae0f0d..8deec86ecbcd 100644
> >>> --- a/lib/utils.c
> >>> +++ b/lib/utils.c
> >>> @@ -1763,3 +1763,11 @@ int parse_on_off(const char *msg, const char *realval, int *p_err)
> >>>
> >>>  	return parse_one_of(msg, realval, values_on_off, ARRAY_SIZE(values_on_off), p_err);
> >>>  }
> >>> +
> >>> +void print_on_off_bool(FILE *fp, const char *flag, bool val)
> >>> +{
> >>> +	if (is_json_context())
> >>> +		print_bool(PRINT_JSON, flag, NULL, val);
> >>> +	else
> >>> +		fprintf(fp, "%s %s ", flag, val ? "on" : "off");
> >>> +}
> >>>
> >>
> >> I think print_on_off should be fine and aligns with parse_on_off once it
> >> returns a bool.
> >
> > print_on_off() is already used in the RDMA tool, and actually outputs
> > "on" and "off", unlike this. So I chose this instead.
> >
> > I could rename the RDMA one though -- it's used in two places, whereas
> > this is used in about two dozen instances across the codebase.
> >
>
> yes, the rdma utils are using generic function names. The rdma version
> should be renamed; perhaps rd_print_on_off. That seems to be once common
> prefix. Added Leon.

I made fast experiment and the output for the code proposed here and existed
in the RDMAtool - result the same. So the good thing will be to delete the
function from the RDMA after print_on_off_bool() will be improved.

However I don't understand why print_on_off_bool() is implemented in
utils.c and not in lib/json_print.c that properly handles JSON context,
provide colorized output and doesn't require to supply FILE *fp.

Thanks

Re: [PATCH iproute2-next v2 03/11] lib: utils: Add print_on_off_bool()

[David Ahern]

On 11/1/20 11:37 PM, Leon Romanovsky wrote:
> However I don't understand why print_on_off_bool() is implemented in
> utils.c and not in lib/json_print.c that properly handles JSON context,
> provide colorized output and doesn't require to supply FILE *fp.

Good point, I missed that earlier.

Re: [PATCH iproute2-next v2 03/11] lib: utils: Add print_on_off_bool()

[Petr Machata]

Leon Romanovsky <leon@kernel.org> writes:

> On Sun, Nov 01, 2020 at 04:55:42PM -0700, David Ahern wrote:
>> On 10/31/20 3:23 PM, Petr Machata wrote:
>> >
>> > David Ahern <dsahern@gmail.com> writes:
>> >
>> >> On 10/30/20 6:29 AM, Petr Machata wrote:
>> >>> diff --git a/lib/utils.c b/lib/utils.c
>> >>> index 930877ae0f0d..8deec86ecbcd 100644
>> >>> --- a/lib/utils.c
>> >>> +++ b/lib/utils.c
>> >>> @@ -1763,3 +1763,11 @@ int parse_on_off(const char *msg, const char *realval, int *p_err)
>> >>>
>> >>>  	return parse_one_of(msg, realval, values_on_off, ARRAY_SIZE(values_on_off), p_err);
>> >>>  }
>> >>> +
>> >>> +void print_on_off_bool(FILE *fp, const char *flag, bool val)
>> >>> +{
>> >>> +	if (is_json_context())
>> >>> +		print_bool(PRINT_JSON, flag, NULL, val);
>> >>> +	else
>> >>> +		fprintf(fp, "%s %s ", flag, val ? "on" : "off");
>> >>> +}
>> >>>
>> >>
>> >> I think print_on_off should be fine and aligns with parse_on_off once it
>> >> returns a bool.
>> >
>> > print_on_off() is already used in the RDMA tool, and actually outputs
>> > "on" and "off", unlike this. So I chose this instead.
>> >
>> > I could rename the RDMA one though -- it's used in two places, whereas
>> > this is used in about two dozen instances across the codebase.
>> >
>>
>> yes, the rdma utils are using generic function names. The rdma version
>> should be renamed; perhaps rd_print_on_off. That seems to be once common
>> prefix. Added Leon.
>
> I made fast experiment and the output for the code proposed here and existed
> in the RDMAtool - result the same. So the good thing will be to delete the
> function from the RDMA after print_on_off_bool() will be improved.

The RDMAtool uses literal "on" and "off" as values in JSON, not
booleans. Moving over to print_on_off_bool() would be a breaking change,
which is problematic especially in JSON output.

> However I don't understand why print_on_off_bool() is implemented in
> utils.c and not in lib/json_print.c that properly handles JSON context,

There's a whole lot of print_X functions for printing non-fundamental
data types in utils.c. Seemed obvious to put it there. I can move it to
json_print.c, no problem.

I think the current function does handle JSON context, what else do
you have in mind?

> provide colorized output and doesn't require to supply FILE *fp.

Stephen Hemminger already pointed out the FILE *fp bit, I'll be removing
it.

Re: [PATCH iproute2-next v2 03/11] lib: utils: Add print_on_off_bool()

[Leon Romanovsky]

On Tue, Nov 03, 2020 at 12:05:20AM +0100, Petr Machata wrote:
>
> Leon Romanovsky <leon@kernel.org> writes:
>
> > On Sun, Nov 01, 2020 at 04:55:42PM -0700, David Ahern wrote:
> >> On 10/31/20 3:23 PM, Petr Machata wrote:
> >> >
> >> > David Ahern <dsahern@gmail.com> writes:
> >> >
> >> >> On 10/30/20 6:29 AM, Petr Machata wrote:
> >> >>> diff --git a/lib/utils.c b/lib/utils.c
> >> >>> index 930877ae0f0d..8deec86ecbcd 100644
> >> >>> --- a/lib/utils.c
> >> >>> +++ b/lib/utils.c
> >> >>> @@ -1763,3 +1763,11 @@ int parse_on_off(const char *msg, const char *realval, int *p_err)
> >> >>>
> >> >>>  	return parse_one_of(msg, realval, values_on_off, ARRAY_SIZE(values_on_off), p_err);
> >> >>>  }
> >> >>> +
> >> >>> +void print_on_off_bool(FILE *fp, const char *flag, bool val)
> >> >>> +{
> >> >>> +	if (is_json_context())
> >> >>> +		print_bool(PRINT_JSON, flag, NULL, val);
> >> >>> +	else
> >> >>> +		fprintf(fp, "%s %s ", flag, val ? "on" : "off");
> >> >>> +}
> >> >>>
> >> >>
> >> >> I think print_on_off should be fine and aligns with parse_on_off once it
> >> >> returns a bool.
> >> >
> >> > print_on_off() is already used in the RDMA tool, and actually outputs
> >> > "on" and "off", unlike this. So I chose this instead.
> >> >
> >> > I could rename the RDMA one though -- it's used in two places, whereas
> >> > this is used in about two dozen instances across the codebase.
> >> >
> >>
> >> yes, the rdma utils are using generic function names. The rdma version
> >> should be renamed; perhaps rd_print_on_off. That seems to be once common
> >> prefix. Added Leon.
> >
> > I made fast experiment and the output for the code proposed here and existed
> > in the RDMAtool - result the same. So the good thing will be to delete the
> > function from the RDMA after print_on_off_bool() will be improved.
>
> The RDMAtool uses literal "on" and "off" as values in JSON, not
> booleans. Moving over to print_on_off_bool() would be a breaking change,
> which is problematic especially in JSON output.

Nothing prohibits us from adding extra parameter to this new
function/json logic/json type that will control JSON behavior. Personally,
I don't think that json and stdout outputs should be different, e.g. 1/0 for
the json and on/off for the stdout.

>
> > However I don't understand why print_on_off_bool() is implemented in
> > utils.c and not in lib/json_print.c that properly handles JSON context,
>
> There's a whole lot of print_X functions for printing non-fundamental
> data types in utils.c. Seemed obvious to put it there. I can move it to
> json_print.c, no problem.

It looks like it is worth to cleanup util.c and make sure that all
prints are gathered in one place. Out of the scope for this series.

>
> I think the current function does handle JSON context, what else do
> you have in mind?a

It handles, but does it twice, first time for is_json_context() and
second time inside print_bool.

>
> > provide colorized output and doesn't require to supply FILE *fp.
>
> Stephen Hemminger already pointed out the FILE *fp bit, I'll be removing
> it.

Re: [PATCH iproute2-next v2 03/11] lib: utils: Add print_on_off_bool()

[Petr Machata]

Leon Romanovsky <leon@kernel.org> writes:

> On Tue, Nov 03, 2020 at 12:05:20AM +0100, Petr Machata wrote:
>>
>> Leon Romanovsky <leon@kernel.org> writes:
>>
>> > On Sun, Nov 01, 2020 at 04:55:42PM -0700, David Ahern wrote:
>> >
>> >> yes, the rdma utils are using generic function names. The rdma version
>> >> should be renamed; perhaps rd_print_on_off. That seems to be once common
>> >> prefix. Added Leon.
>> >
>> > I made fast experiment and the output for the code proposed here and existed
>> > in the RDMAtool - result the same. So the good thing will be to delete the
>> > function from the RDMA after print_on_off_bool() will be improved.
>>
>> The RDMAtool uses literal "on" and "off" as values in JSON, not
>> booleans. Moving over to print_on_off_bool() would be a breaking change,
>> which is problematic especially in JSON output.
>
> Nothing prohibits us from adding extra parameter to this new
> function/json logic/json type that will control JSON behavior. Personally,
> I don't think that json and stdout outputs should be different, e.g. 1/0 for
> the json and on/off for the stdout.

Emitting on/off in JSON as true booleans (true / false, not 1 / 0) does
make sense. It's programmatically-consumed interface, the values should
be of the right type.

On the other hand, having a FP output use literal "on" and "off" makes
sense as well. It's an obvious reference to the command line, you can
actually cut'n'paste it back to shell and it will do the right thing.

Many places in iproute2 do do this dual output, and ideally all new
instances would behave this way as well. So no toggles, please.

>> I think the current function does handle JSON context, what else do
>> you have in mind?
>
> It handles, but does it twice, first time for is_json_context() and
> second time inside print_bool.

Gotcha.

Re: [PATCH iproute2-next v2 03/11] lib: utils: Add print_on_off_bool()

[Leon Romanovsky]

On Tue, Nov 03, 2020 at 10:01:32PM +0100, Petr Machata wrote:
>
> Leon Romanovsky <leon@kernel.org> writes:
>
> > On Tue, Nov 03, 2020 at 12:05:20AM +0100, Petr Machata wrote:
> >>
> >> Leon Romanovsky <leon@kernel.org> writes:
> >>
> >> > On Sun, Nov 01, 2020 at 04:55:42PM -0700, David Ahern wrote:
> >> >
> >> >> yes, the rdma utils are using generic function names. The rdma version
> >> >> should be renamed; perhaps rd_print_on_off. That seems to be once common
> >> >> prefix. Added Leon.
> >> >
> >> > I made fast experiment and the output for the code proposed here and existed
> >> > in the RDMAtool - result the same. So the good thing will be to delete the
> >> > function from the RDMA after print_on_off_bool() will be improved.
> >>
> >> The RDMAtool uses literal "on" and "off" as values in JSON, not
> >> booleans. Moving over to print_on_off_bool() would be a breaking change,
> >> which is problematic especially in JSON output.
> >
> > Nothing prohibits us from adding extra parameter to this new
> > function/json logic/json type that will control JSON behavior. Personally,
> > I don't think that json and stdout outputs should be different, e.g. 1/0 for
> > the json and on/off for the stdout.
>
> Emitting on/off in JSON as true booleans (true / false, not 1 / 0) does
> make sense. It's programmatically-consumed interface, the values should
> be of the right type.

As long as you don't need to use those fields to "set .." after that.

>
> On the other hand, having a FP output use literal "on" and "off" makes
> sense as well. It's an obvious reference to the command line, you can
> actually cut'n'paste it back to shell and it will do the right thing.

Maybe it is not so bad to change RDMAtool to general function, this
on/of print is not widely use yet, just need to decide what is the right one.

>
> Many places in iproute2 do do this dual output, and ideally all new
> instances would behave this way as well. So no toggles, please.

Good example why all utilities in iproute2 are better to use same
input/output code and any attempt to make custom variants should be
banned.

>
> >> I think the current function does handle JSON context, what else do
> >> you have in mind?
> >
> > It handles, but does it twice, first time for is_json_context() and
> > second time inside print_bool.
>
> Gotcha.

Re: [PATCH iproute2-next v2 03/11] lib: utils: Add print_on_off_bool()

[Petr Machata]

Leon Romanovsky <leon@kernel.org> writes:

> On Tue, Nov 03, 2020 at 10:01:32PM +0100, Petr Machata wrote:
>>
>> Leon Romanovsky <leon@kernel.org> writes:
>>
>> > On Tue, Nov 03, 2020 at 12:05:20AM +0100, Petr Machata wrote:
>> >>
>> >> Leon Romanovsky <leon@kernel.org> writes:
>> >>
>> >> > On Sun, Nov 01, 2020 at 04:55:42PM -0700, David Ahern wrote:
>> >> >
>> >> >> yes, the rdma utils are using generic function names. The rdma version
>> >> >> should be renamed; perhaps rd_print_on_off. That seems to be once common
>> >> >> prefix. Added Leon.
>> >> >
>> >> > I made fast experiment and the output for the code proposed here and existed
>> >> > in the RDMAtool - result the same. So the good thing will be to delete the
>> >> > function from the RDMA after print_on_off_bool() will be improved.
>> >>
>> >> The RDMAtool uses literal "on" and "off" as values in JSON, not
>> >> booleans. Moving over to print_on_off_bool() would be a breaking change,
>> >> which is problematic especially in JSON output.
>> >
>> > Nothing prohibits us from adding extra parameter to this new
>> > function/json logic/json type that will control JSON behavior. Personally,
>> > I don't think that json and stdout outputs should be different, e.g. 1/0 for
>> > the json and on/off for the stdout.
>>
>> Emitting on/off in JSON as true booleans (true / false, not 1 / 0) does
>> make sense. It's programmatically-consumed interface, the values should
>> be of the right type.
>
> As long as you don't need to use those fields to "set .." after that.
>>
>> On the other hand, having a FP output use literal "on" and "off" makes
>> sense as well. It's an obvious reference to the command line, you can
>> actually cut'n'paste it back to shell and it will do the right thing.
>
> Maybe it is not so bad to change RDMAtool to general function, this
> on/of print is not widely use yet

OK, if you think the API breakage is acceptable, I'll roll this into the
patchset.

> just need to decide what is the right one.

Yeah, it's kinda fuzzy. Where JSON has an obvious type to use, use it:
arrays should probably be arrays, numbers should probably be numbers.
I'm not so sure about enums, but I guess represent them as strings? As
numbers they will not be more meaningful or easy to consume, and it does
not make sense to do arithmetic on enums.

On/off toggles could be considered enums. But they are also booleans.
Representing on as true and off as false is straightforward and from
this perspective booleans are the obvious type to use.

>> Many places in iproute2 do do this dual output, and ideally all new
>> instances would behave this way as well. So no toggles, please.
>
> Good example why all utilities in iproute2 are better to use same
> input/output code and any attempt to make custom variants should be
> banned.

Yes, I have a clean-up patch that converts these custom on/off helpers
to the new central one. I'll send this together with other refactorings
of this sort after this patch set.

[PATCH iproute2-next v2 04/11] lib: Extract from devlink/mnlg a helper, mnlu_socket_open()

[Petr Machata]

This little dance of mnl_socket_open(), option setting, and bind, is the
same regardless of tool. Extract into a new module that should hold helpers
for working with libmnl, mnl_util.c.

Signed-off-by: Petr Machata <me@pmachata.org>
---

Notes:
    v2:
    - Add SPDX-License-Identifier

 devlink/Makefile    |  2 +-
 devlink/mnlg.c      | 19 ++++---------------
 include/mnl_utils.h |  7 +++++++
 lib/Makefile        |  2 +-
 lib/mnl_utils.c     | 30 ++++++++++++++++++++++++++++++
 5 files changed, 43 insertions(+), 17 deletions(-)
 create mode 100644 include/mnl_utils.h
 create mode 100644 lib/mnl_utils.c

diff --git a/devlink/Makefile b/devlink/Makefile
index 7da7d1fa18d5..d540feb3c012 100644
--- a/devlink/Makefile
+++ b/devlink/Makefile
@@ -12,7 +12,7 @@ endif
 
 all: $(TARGETS) $(LIBS)
 
-devlink: $(DEVLINKOBJ)
+devlink: $(DEVLINKOBJ) $(LIBNETLINK)
 	$(QUIET_LINK)$(CC) $^ $(LDFLAGS) $(LDLIBS) -o $@
 
 install: all
diff --git a/devlink/mnlg.c b/devlink/mnlg.c
index c7d25e8713a1..9817bbad5e7d 100644
--- a/devlink/mnlg.c
+++ b/devlink/mnlg.c
@@ -19,6 +19,7 @@
 #include <linux/genetlink.h>
 
 #include "libnetlink.h"
+#include "mnl_utils.h"
 #include "utils.h"
 #include "mnlg.h"
 
@@ -263,7 +264,6 @@ struct mnlg_socket *mnlg_socket_open(const char *family_name, uint8_t version)
 {
 	struct mnlg_socket *nlg;
 	struct nlmsghdr *nlh;
-	int one = 1;
 	int err;
 
 	nlg = malloc(sizeof(*nlg));
@@ -274,19 +274,9 @@ struct mnlg_socket *mnlg_socket_open(const char *family_name, uint8_t version)
 	if (!nlg->buf)
 		goto err_buf_alloc;
 
-	nlg->nl = mnl_socket_open(NETLINK_GENERIC);
+	nlg->nl = mnlu_socket_open(NETLINK_GENERIC);
 	if (!nlg->nl)
-		goto err_mnl_socket_open;
-
-	/* Older kernels may no support capped/extended ACK reporting */
-	mnl_socket_setsockopt(nlg->nl, NETLINK_CAP_ACK, &one, sizeof(one));
-	mnl_socket_setsockopt(nlg->nl, NETLINK_EXT_ACK, &one, sizeof(one));
-
-	err = mnl_socket_bind(nlg->nl, 0, MNL_SOCKET_AUTOPID);
-	if (err < 0)
-		goto err_mnl_socket_bind;
-
-	nlg->portid = mnl_socket_get_portid(nlg->nl);
+		goto err_socket_open;
 
 	nlh = __mnlg_msg_prepare(nlg, CTRL_CMD_GETFAMILY,
 				 NLM_F_REQUEST | NLM_F_ACK, GENL_ID_CTRL, 1);
@@ -305,9 +295,8 @@ struct mnlg_socket *mnlg_socket_open(const char *family_name, uint8_t version)
 
 err_mnlg_socket_recv_run:
 err_mnlg_socket_send:
-err_mnl_socket_bind:
 	mnl_socket_close(nlg->nl);
-err_mnl_socket_open:
+err_socket_open:
 	free(nlg->buf);
 err_buf_alloc:
 	free(nlg);
diff --git a/include/mnl_utils.h b/include/mnl_utils.h
new file mode 100644
index 000000000000..10a064afdfe8
--- /dev/null
+++ b/include/mnl_utils.h
@@ -0,0 +1,7 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __MNL_UTILS_H__
+#define __MNL_UTILS_H__ 1
+
+struct mnl_socket *mnlu_socket_open(int bus);
+
+#endif /* __MNL_UTILS_H__ */
diff --git a/lib/Makefile b/lib/Makefile
index 7cba1857b7fa..13f4ee15373b 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -7,7 +7,7 @@ UTILOBJ = utils.o rt_names.o ll_map.o ll_types.o ll_proto.o ll_addr.o \
 	inet_proto.o namespace.o json_writer.o json_print.o \
 	names.o color.o bpf.o exec.o fs.o cg_map.o
 
-NLOBJ=libgenl.o libnetlink.o
+NLOBJ=libgenl.o libnetlink.o mnl_utils.o
 
 all: libnetlink.a libutil.a
 
diff --git a/lib/mnl_utils.c b/lib/mnl_utils.c
new file mode 100644
index 000000000000..2426912aa511
--- /dev/null
+++ b/lib/mnl_utils.c
@@ -0,0 +1,30 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * mnl_utils.c	Helpers for working with libmnl.
+ */
+
+#include <libmnl/libmnl.h>
+
+#include "mnl_utils.h"
+
+struct mnl_socket *mnlu_socket_open(int bus)
+{
+	struct mnl_socket *nl;
+	int one = 1;
+
+	nl = mnl_socket_open(bus);
+	if (nl == NULL)
+		return NULL;
+
+	mnl_socket_setsockopt(nl, NETLINK_CAP_ACK, &one, sizeof(one));
+	mnl_socket_setsockopt(nl, NETLINK_EXT_ACK, &one, sizeof(one));
+
+	if (mnl_socket_bind(nl, 0, MNL_SOCKET_AUTOPID) < 0)
+		goto err_bind;
+
+	return nl;
+
+err_bind:
+	mnl_socket_close(nl);
+	return NULL;
+}
-- 
2.25.1

[PATCH iproute2-next v2 05/11] lib: Extract from devlink/mnlg a helper, mnlu_msg_prepare()

[Petr Machata]

Allocation of a new netlink message with the two usual headers is reusable
with other netlink netlink message types. Extract it into a helper,
mnlu_msg_prepare(). Take the second header as an argument, instead of
passing in parameters to initialize it, and copy it in.

Signed-off-by: Petr Machata <me@pmachata.org>
---
 devlink/mnlg.c      | 18 ++++++------------
 include/mnl_utils.h |  2 ++
 lib/mnl_utils.c     | 19 +++++++++++++++++++
 3 files changed, 27 insertions(+), 12 deletions(-)

diff --git a/devlink/mnlg.c b/devlink/mnlg.c
index 9817bbad5e7d..4995b7af06a3 100644
--- a/devlink/mnlg.c
+++ b/devlink/mnlg.c
@@ -14,7 +14,6 @@
 #include <string.h>
 #include <errno.h>
 #include <unistd.h>
-#include <time.h>
 #include <libmnl/libmnl.h>
 #include <linux/genetlink.h>
 
@@ -36,19 +35,14 @@ static struct nlmsghdr *__mnlg_msg_prepare(struct mnlg_socket *nlg, uint8_t cmd,
 					   uint16_t flags, uint32_t id,
 					   uint8_t version)
 {
+	struct genlmsghdr genl = {
+		.cmd = cmd,
+		.version = version,
+	};
 	struct nlmsghdr *nlh;
-	struct genlmsghdr *genl;
-
-	nlh = mnl_nlmsg_put_header(nlg->buf);
-	nlh->nlmsg_type	= id;
-	nlh->nlmsg_flags = flags;
-	nlg->seq = time(NULL);
-	nlh->nlmsg_seq = nlg->seq;
-
-	genl = mnl_nlmsg_put_extra_header(nlh, sizeof(struct genlmsghdr));
-	genl->cmd = cmd;
-	genl->version = version;
 
+	nlh = mnlu_msg_prepare(nlg->buf, id, flags, &genl, sizeof(genl));
+	nlg->seq = nlh->nlmsg_seq;
 	return nlh;
 }
 
diff --git a/include/mnl_utils.h b/include/mnl_utils.h
index 10a064afdfe8..86ce30f49a94 100644
--- a/include/mnl_utils.h
+++ b/include/mnl_utils.h
@@ -3,5 +3,7 @@
 #define __MNL_UTILS_H__ 1
 
 struct mnl_socket *mnlu_socket_open(int bus);
+struct nlmsghdr *mnlu_msg_prepare(void *buf, uint32_t nlmsg_type, uint16_t flags,
+				  void *extra_header, size_t extra_header_size);
 
 #endif /* __MNL_UTILS_H__ */
diff --git a/lib/mnl_utils.c b/lib/mnl_utils.c
index 2426912aa511..61e8060ecbca 100644
--- a/lib/mnl_utils.c
+++ b/lib/mnl_utils.c
@@ -3,6 +3,8 @@
  * mnl_utils.c	Helpers for working with libmnl.
  */
 
+#include <string.h>
+#include <time.h>
 #include <libmnl/libmnl.h>
 
 #include "mnl_utils.h"
@@ -28,3 +30,20 @@ err_bind:
 	mnl_socket_close(nl);
 	return NULL;
 }
+
+struct nlmsghdr *mnlu_msg_prepare(void *buf, uint32_t nlmsg_type, uint16_t flags,
+				  void *extra_header, size_t extra_header_size)
+{
+	struct nlmsghdr *nlh;
+	void *eh;
+
+	nlh = mnl_nlmsg_put_header(buf);
+	nlh->nlmsg_type = nlmsg_type;
+	nlh->nlmsg_flags = flags;
+	nlh->nlmsg_seq = time(NULL);
+
+	eh = mnl_nlmsg_put_extra_header(nlh, extra_header_size);
+	memcpy(eh, extra_header, extra_header_size);
+
+	return nlh;
+}
-- 
2.25.1

[PATCH iproute2-next v2 06/11] lib: Extract from devlink/mnlg a helper, mnlu_socket_recv_run()

[Petr Machata]

Receiving a message in libmnl is a somewhat involved operation. Devlink's
mnlg library has an implementation that is going to be handy for other
tools as well. Extract it into a new helper.

Signed-off-by: Petr Machata <me@pmachata.org>
---
 devlink/mnlg.c      | 56 ++---------------------------------------
 include/mnl_utils.h |  2 ++
 lib/mnl_utils.c     | 61 +++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 65 insertions(+), 54 deletions(-)

diff --git a/devlink/mnlg.c b/devlink/mnlg.c
index 4995b7af06a3..21b10c5a5669 100644
--- a/devlink/mnlg.c
+++ b/devlink/mnlg.c
@@ -28,7 +28,6 @@ struct mnlg_socket {
 	uint32_t id;
 	uint8_t version;
 	unsigned int seq;
-	unsigned int portid;
 };
 
 static struct nlmsghdr *__mnlg_msg_prepare(struct mnlg_socket *nlg, uint8_t cmd,
@@ -57,61 +56,10 @@ int mnlg_socket_send(struct mnlg_socket *nlg, const struct nlmsghdr *nlh)
 	return mnl_socket_sendto(nlg->nl, nlh, nlh->nlmsg_len);
 }
 
-static int mnlg_cb_noop(const struct nlmsghdr *nlh, void *data)
-{
-	return MNL_CB_OK;
-}
-
-static int mnlg_cb_error(const struct nlmsghdr *nlh, void *data)
-{
-	const struct nlmsgerr *err = mnl_nlmsg_get_payload(nlh);
-
-	/* Netlink subsystems returns the errno value with different signess */
-	if (err->error < 0)
-		errno = -err->error;
-	else
-		errno = err->error;
-
-	if (nl_dump_ext_ack(nlh, NULL))
-		return MNL_CB_ERROR;
-
-	return err->error == 0 ? MNL_CB_STOP : MNL_CB_ERROR;
-}
-
-static int mnlg_cb_stop(const struct nlmsghdr *nlh, void *data)
-{
-	int len = *(int *)NLMSG_DATA(nlh);
-
-	if (len < 0) {
-		errno = -len;
-		nl_dump_ext_ack_done(nlh, len);
-		return MNL_CB_ERROR;
-	}
-	return MNL_CB_STOP;
-}
-
-static mnl_cb_t mnlg_cb_array[NLMSG_MIN_TYPE] = {
-	[NLMSG_NOOP]	= mnlg_cb_noop,
-	[NLMSG_ERROR]	= mnlg_cb_error,
-	[NLMSG_DONE]	= mnlg_cb_stop,
-	[NLMSG_OVERRUN]	= mnlg_cb_noop,
-};
-
 int mnlg_socket_recv_run(struct mnlg_socket *nlg, mnl_cb_t data_cb, void *data)
 {
-	int err;
-
-	do {
-		err = mnl_socket_recvfrom(nlg->nl, nlg->buf,
-					  MNL_SOCKET_BUFFER_SIZE);
-		if (err <= 0)
-			break;
-		err = mnl_cb_run2(nlg->buf, err, nlg->seq, nlg->portid,
-				  data_cb, data, mnlg_cb_array,
-				  ARRAY_SIZE(mnlg_cb_array));
-	} while (err > 0);
-
-	return err;
+	return mnlu_socket_recv_run(nlg->nl, nlg->seq, nlg->buf, MNL_SOCKET_BUFFER_SIZE,
+				    data_cb, data);
 }
 
 struct group_info {
diff --git a/include/mnl_utils.h b/include/mnl_utils.h
index 86ce30f49a94..fa826ef1f8fe 100644
--- a/include/mnl_utils.h
+++ b/include/mnl_utils.h
@@ -5,5 +5,7 @@
 struct mnl_socket *mnlu_socket_open(int bus);
 struct nlmsghdr *mnlu_msg_prepare(void *buf, uint32_t nlmsg_type, uint16_t flags,
 				  void *extra_header, size_t extra_header_size);
+int mnlu_socket_recv_run(struct mnl_socket *nl, unsigned int seq, void *buf, size_t buf_size,
+			 mnl_cb_t cb, void *data);
 
 #endif /* __MNL_UTILS_H__ */
diff --git a/lib/mnl_utils.c b/lib/mnl_utils.c
index 61e8060ecbca..46384ff81cf1 100644
--- a/lib/mnl_utils.c
+++ b/lib/mnl_utils.c
@@ -3,11 +3,14 @@
  * mnl_utils.c	Helpers for working with libmnl.
  */
 
+#include <errno.h>
 #include <string.h>
 #include <time.h>
 #include <libmnl/libmnl.h>
 
+#include "libnetlink.h"
 #include "mnl_utils.h"
+#include "utils.h"
 
 struct mnl_socket *mnlu_socket_open(int bus)
 {
@@ -47,3 +50,61 @@ struct nlmsghdr *mnlu_msg_prepare(void *buf, uint32_t nlmsg_type, uint16_t flags
 
 	return nlh;
 }
+
+static int mnlu_cb_noop(const struct nlmsghdr *nlh, void *data)
+{
+	return MNL_CB_OK;
+}
+
+static int mnlu_cb_error(const struct nlmsghdr *nlh, void *data)
+{
+	const struct nlmsgerr *err = mnl_nlmsg_get_payload(nlh);
+
+	/* Netlink subsystems returns the errno value with different signess */
+	if (err->error < 0)
+		errno = -err->error;
+	else
+		errno = err->error;
+
+	if (nl_dump_ext_ack(nlh, NULL))
+		return MNL_CB_ERROR;
+
+	return err->error == 0 ? MNL_CB_STOP : MNL_CB_ERROR;
+}
+
+static int mnlu_cb_stop(const struct nlmsghdr *nlh, void *data)
+{
+	int len = *(int *)NLMSG_DATA(nlh);
+
+	if (len < 0) {
+		errno = -len;
+		nl_dump_ext_ack_done(nlh, len);
+		return MNL_CB_ERROR;
+	}
+	return MNL_CB_STOP;
+}
+
+static mnl_cb_t mnlu_cb_array[NLMSG_MIN_TYPE] = {
+	[NLMSG_NOOP]	= mnlu_cb_noop,
+	[NLMSG_ERROR]	= mnlu_cb_error,
+	[NLMSG_DONE]	= mnlu_cb_stop,
+	[NLMSG_OVERRUN]	= mnlu_cb_noop,
+};
+
+int mnlu_socket_recv_run(struct mnl_socket *nl, unsigned int seq, void *buf, size_t buf_size,
+			 mnl_cb_t cb, void *data)
+{
+	unsigned int portid = mnl_socket_get_portid(nl);
+	int err;
+
+	do {
+		err = mnl_socket_recvfrom(nl, buf, buf_size);
+		if (err <= 0)
+			break;
+		err = mnl_cb_run2(buf, err, seq, portid,
+				  cb, data, mnlu_cb_array,
+				  ARRAY_SIZE(mnlu_cb_array));
+	} while (err > 0);
+
+	return err;
+}
-- 
2.25.1

[PATCH iproute2-next v2 07/11] lib: Extract from iplink_vlan a helper to parse key:value arrays

[Petr Machata]

VLAN netdevices have two similar attributes: ingress-qos-map and
egress-qos-map. These attributes can be configured with a series of
802.1-priority-to-skb-priority (and vice versa) mappings. A reusable helper
along those lines will be handy for configuration of various
priority-to-tc, tc-to-algorithm, and other arrays in DCB.

Therefore extract the logic to a function parse_mapping(), move to utils.c,
and dispatch to utils.c from iplink_vlan.c. That necessitates extraction of
a VLAN-specific parse_qos_mapping(). Do that, and propagate addattr_l()
return value up, unlike the original.

Signed-off-by: Petr Machata <me@pmachata.org>
---

Notes:
    v2:
    - In parse_qos_mapping(), propagate return value from addattr_l()
      [Roman Mashak]

 include/utils.h  |  4 ++++
 ip/iplink_vlan.c | 36 +++++++++++++++---------------------
 lib/utils.c      | 28 ++++++++++++++++++++++++++++
 3 files changed, 47 insertions(+), 21 deletions(-)

diff --git a/include/utils.h b/include/utils.h
index e3cdb098834a..1c72221ae92c 100644
--- a/include/utils.h
+++ b/include/utils.h
@@ -330,4 +330,8 @@ int parse_one_of(const char *msg, const char *realval, const char * const *list,
 int parse_on_off(const char *msg, const char *realval, int *p_err);
 void print_on_off_bool(FILE *fp, const char *flag, bool val);
 
+int parse_mapping(int *argcp, char ***argvp,
+		  int (*mapping_cb)(__u32 key, char *value, void *data),
+		  void *mapping_cb_data);
+
 #endif /* __UTILS_H__ */
diff --git a/ip/iplink_vlan.c b/ip/iplink_vlan.c
index 1e6817f5de3d..dadc349db16c 100644
--- a/ip/iplink_vlan.c
+++ b/ip/iplink_vlan.c
@@ -49,36 +49,30 @@ static int on_off(const char *msg, const char *arg)
 	return -1;
 }
 
+static int parse_qos_mapping(__u32 key, char *value, void *data)
+{
+	struct nlmsghdr *n = data;
+	struct ifla_vlan_qos_mapping m = {
+		.from = key,
+	};
+
+	if (get_u32(&m.to, value, 0))
+		return 1;
+
+	return addattr_l(n, 1024, IFLA_VLAN_QOS_MAPPING, &m, sizeof(m));
+}
+
 static int vlan_parse_qos_map(int *argcp, char ***argvp, struct nlmsghdr *n,
 			      int attrtype)
 {
-	int argc = *argcp;
-	char **argv = *argvp;
-	struct ifla_vlan_qos_mapping m;
 	struct rtattr *tail;
 
 	tail = addattr_nest(n, 1024, attrtype);
 
-	while (argc > 0) {
-		char *colon = strchr(*argv, ':');
-
-		if (!colon)
-			break;
-		*colon = '\0';
-
-		if (get_u32(&m.from, *argv, 0))
-			return 1;
-		if (get_u32(&m.to, colon + 1, 0))
-			return 1;
-		argc--, argv++;
-
-		addattr_l(n, 1024, IFLA_VLAN_QOS_MAPPING, &m, sizeof(m));
-	}
+	if (parse_mapping(argcp, argvp, &parse_qos_mapping, n))
+		return 1;
 
 	addattr_nest_end(n, tail);
-
-	*argcp = argc;
-	*argvp = argv;
 	return 0;
 }
 
diff --git a/lib/utils.c b/lib/utils.c
index 8deec86ecbcd..aba7cc0960cd 100644
--- a/lib/utils.c
+++ b/lib/utils.c
@@ -1771,3 +1771,31 @@ void print_on_off_bool(FILE *fp, const char *flag, bool val)
 	else
 		fprintf(fp, "%s %s ", flag, val ? "on" : "off");
 }
+
+int parse_mapping(int *argcp, char ***argvp,
+		  int (*mapping_cb)(__u32 key, char *value, void *data),
+		  void *mapping_cb_data)
+{
+	int argc = *argcp;
+	char **argv = *argvp;
+
+	while (argc > 0) {
+		char *colon = strchr(*argv, ':');
+		__u32 key;
+
+		if (!colon)
+			break;
+		*colon = '\0';
+
+		if (get_u32(&key, *argv, 0))
+			return 1;
+		if (mapping_cb(key, colon + 1, mapping_cb_data))
+			return 1;
+
+		argc--, argv++;
+	}
+
+	*argcp = argc;
+	*argvp = argv;
+	return 0;
+}
-- 
2.25.1

[PATCH iproute2-next v2 08/11] lib: parse_mapping: Update argc, argv on error

[Petr Machata]

Currently argc and argv are not updated unless parsing of all of the
mapping was successful. However in that case, "ip link" will point at the
wrong argument when complaining:

    # ip link add name eth0.100 link eth0 type vlan id 100 egress 1:1 2:foo
    Error: argument "1" is wrong: invalid egress-qos-map

Update argc and argv even in the case of parsing error, so that the right
element is indicated.

Signed-off-by: Petr Machata <me@pmachata.org>
---
 lib/utils.c | 15 ++++++++++-----
 1 file changed, 10 insertions(+), 5 deletions(-)

diff --git a/lib/utils.c b/lib/utils.c
index aba7cc0960cd..089bbde715da 100644
--- a/lib/utils.c
+++ b/lib/utils.c
@@ -1778,6 +1778,7 @@ int parse_mapping(int *argcp, char ***argvp,
 {
 	int argc = *argcp;
 	char **argv = *argvp;
+	int ret = 0;
 
 	while (argc > 0) {
 		char *colon = strchr(*argv, ':');
@@ -1787,15 +1788,19 @@ int parse_mapping(int *argcp, char ***argvp,
 			break;
 		*colon = '\0';
 
-		if (get_u32(&key, *argv, 0))
-			return 1;
-		if (mapping_cb(key, colon + 1, mapping_cb_data))
-			return 1;
+		if (get_u32(&key, *argv, 0)) {
+			ret = 1;
+			break;
+		}
+		if (mapping_cb(key, colon + 1, mapping_cb_data)) {
+			ret = 1;
+			break;
+		}
 
 		argc--, argv++;
 	}
 
 	*argcp = argc;
 	*argvp = argv;
-	return 0;
+	return ret;
 }
-- 
2.25.1

[PATCH iproute2-next v2 09/11] lib: parse_mapping: Recognize a keyword "all"

[Petr Machata]

The DCB tool will have to provide an interface to a number of fixed-size
arrays. Unlike the egress- and ingress-qos-map, it makes good sense to have
an interface to set all members to the same value. For example to set
strict priority on all TCs besides select few, or to reset allocated
bandwidth to all zeroes, again besides several explicitly-given ones.

To support this usage, extend the parse_mapping() with a boolean that
determines whether this special use is supported. If "all" is given and
recognized, mapping_cb is called with the key of -1.

Have iplink_vlan pass false for allow_all.

Signed-off-by: Petr Machata <me@pmachata.org>
---
 include/utils.h  | 2 +-
 ip/iplink_vlan.c | 2 +-
 lib/utils.c      | 6 ++++--
 3 files changed, 6 insertions(+), 4 deletions(-)

diff --git a/include/utils.h b/include/utils.h
index 1c72221ae92c..8ec1b7ab0d8d 100644
--- a/include/utils.h
+++ b/include/utils.h
@@ -330,7 +330,7 @@ int parse_one_of(const char *msg, const char *realval, const char * const *list,
 int parse_on_off(const char *msg, const char *realval, int *p_err);
 void print_on_off_bool(FILE *fp, const char *flag, bool val);
 
-int parse_mapping(int *argcp, char ***argvp,
+int parse_mapping(int *argcp, char ***argvp, bool allow_all,
 		  int (*mapping_cb)(__u32 key, char *value, void *data),
 		  void *mapping_cb_data);
 
diff --git a/ip/iplink_vlan.c b/ip/iplink_vlan.c
index dadc349db16c..1426f2afca23 100644
--- a/ip/iplink_vlan.c
+++ b/ip/iplink_vlan.c
@@ -69,7 +69,7 @@ static int vlan_parse_qos_map(int *argcp, char ***argvp, struct nlmsghdr *n,
 
 	tail = addattr_nest(n, 1024, attrtype);
 
-	if (parse_mapping(argcp, argvp, &parse_qos_mapping, n))
+	if (parse_mapping(argcp, argvp, false, &parse_qos_mapping, n))
 		return 1;
 
 	addattr_nest_end(n, tail);
diff --git a/lib/utils.c b/lib/utils.c
index 089bbde715da..3b3b42b15013 100644
--- a/lib/utils.c
+++ b/lib/utils.c
@@ -1772,7 +1772,7 @@ void print_on_off_bool(FILE *fp, const char *flag, bool val)
 		fprintf(fp, "%s %s ", flag, val ? "on" : "off");
 }
 
-int parse_mapping(int *argcp, char ***argvp,
+int parse_mapping(int *argcp, char ***argvp, bool allow_all,
 		  int (*mapping_cb)(__u32 key, char *value, void *data),
 		  void *mapping_cb_data)
 {
@@ -1788,7 +1788,9 @@ int parse_mapping(int *argcp, char ***argvp,
 			break;
 		*colon = '\0';
 
-		if (get_u32(&key, *argv, 0)) {
+		if (allow_all && matches(*argv, "all") == 0) {
+			key = (__u32) -1;
+		} else if (get_u32(&key, *argv, 0)) {
 			ret = 1;
 			break;
 		}
-- 
2.25.1

[PATCH iproute2-next v2 10/11] Add skeleton of a new tool, dcb

[Petr Machata]

The Linux DCB interface allows configuration of a broad range of
hardware-specific attributes, such as TC scheduling, flow control, per-port
buffer configuration, TC rate, etc. Add a new tool to show that
configuration and tweak it.

DCB allows configuration of several objects, and possibly could expand to
pre-standard CEE interfaces. Therefore the tool itself is a lean shell that
dispatches to subtools each dedicated to one of the objects.

Signed-off-by: Petr Machata <me@pmachata.org>
---
 Makefile       |   2 +-
 dcb/Makefile   |  24 +++
 dcb/dcb.c      | 401 +++++++++++++++++++++++++++++++++++++++++++++++++
 dcb/dcb.h      |  35 +++++
 man/man8/dcb.8 | 103 +++++++++++++
 5 files changed, 564 insertions(+), 1 deletion(-)
 create mode 100644 dcb/Makefile
 create mode 100644 dcb/dcb.c
 create mode 100644 dcb/dcb.h
 create mode 100644 man/man8/dcb.8

diff --git a/Makefile b/Makefile
index 5b040415a12b..e64c65992585 100644
--- a/Makefile
+++ b/Makefile
@@ -55,7 +55,7 @@ WFLAGS += -Wmissing-declarations -Wold-style-definition -Wformat=2
 CFLAGS := $(WFLAGS) $(CCOPTS) -I../include -I../include/uapi $(DEFINES) $(CFLAGS)
 YACCFLAGS = -d -t -v
 
-SUBDIRS=lib ip tc bridge misc netem genl tipc devlink rdma man
+SUBDIRS=lib ip tc bridge misc netem genl tipc devlink rdma dcb man
 
 LIBNETLINK=../lib/libutil.a ../lib/libnetlink.a
 LDLIBS += $(LIBNETLINK)
diff --git a/dcb/Makefile b/dcb/Makefile
new file mode 100644
index 000000000000..9966c8f0bfa4
--- /dev/null
+++ b/dcb/Makefile
@@ -0,0 +1,24 @@
+# SPDX-License-Identifier: GPL-2.0
+include ../config.mk
+
+TARGETS :=
+
+ifeq ($(HAVE_MNL),y)
+
+DCBOBJ = dcb.o
+TARGETS += dcb
+
+endif
+
+all: $(TARGETS) $(LIBS)
+
+dcb: $(DCBOBJ) $(LIBNETLINK)
+	$(QUIET_LINK)$(CC) $^ $(LDFLAGS) $(LDLIBS) -o $@
+
+install: all
+	for i in $(TARGETS); \
+	do install -m 0755 $$i $(DESTDIR)$(SBINDIR); \
+	done
+
+clean:
+	rm -f $(DCBOBJ) $(TARGETS)
diff --git a/dcb/dcb.c b/dcb/dcb.c
new file mode 100644
index 000000000000..26c1f91e815a
--- /dev/null
+++ b/dcb/dcb.c
@@ -0,0 +1,401 @@
+// SPDX-License-Identifier: GPL-2.0+
+
+#include <stdio.h>
+#include <linux/dcbnl.h>
+#include <libmnl/libmnl.h>
+#include <getopt.h>
+
+#include "dcb.h"
+#include "mnl_utils.h"
+#include "namespace.h"
+#include "utils.h"
+#include "version.h"
+
+static int dcb_init(struct dcb *dcb)
+{
+	dcb->buf = malloc(MNL_SOCKET_BUFFER_SIZE);
+	if (dcb->buf == NULL) {
+		perror("Netlink buffer allocation");
+		return -1;
+	}
+
+	dcb->nl = mnlu_socket_open(NETLINK_ROUTE);
+	if (dcb->nl == NULL) {
+		perror("Open netlink socket");
+		goto err_socket_open;
+	}
+
+	new_json_obj_plain(dcb->json_output);
+	return 0;
+
+err_socket_open:
+	free(dcb->buf);
+	return -1;
+}
+
+static void dcb_fini(struct dcb *dcb)
+{
+	delete_json_obj_plain();
+	mnl_socket_close(dcb->nl);
+}
+
+static struct dcb *dcb_alloc(void)
+{
+	struct dcb *dcb;
+
+	dcb = calloc(1, sizeof(*dcb));
+	if (!dcb)
+		return NULL;
+	return dcb;
+}
+
+static void dcb_free(struct dcb *dcb)
+{
+	free(dcb);
+}
+
+struct dcb_get_attribute {
+	struct dcb *dcb;
+	int attr;
+	void *data;
+	size_t data_len;
+};
+
+static int dcb_get_attribute_attr_ieee_cb(const struct nlattr *attr, void *data)
+{
+	struct dcb_get_attribute *ga = data;
+	uint16_t len;
+
+	if (mnl_attr_get_type(attr) != ga->attr)
+		return MNL_CB_OK;
+
+	len = mnl_attr_get_payload_len(attr);
+	if (len != ga->data_len) {
+		fprintf(stderr, "Wrong len %d, expected %zd\n", len, ga->data_len);
+		return MNL_CB_ERROR;
+	}
+
+	memcpy(ga->data, mnl_attr_get_payload(attr), ga->data_len);
+	return MNL_CB_STOP;
+}
+
+static int dcb_get_attribute_attr_cb(const struct nlattr *attr, void *data)
+{
+	if (mnl_attr_get_type(attr) != DCB_ATTR_IEEE)
+		return MNL_CB_OK;
+
+	return mnl_attr_parse_nested(attr, dcb_get_attribute_attr_ieee_cb, data);
+}
+
+static int dcb_get_attribute_cb(const struct nlmsghdr *nlh, void *data)
+{
+	return mnl_attr_parse(nlh, sizeof(struct dcbmsg), dcb_get_attribute_attr_cb, data);
+}
+
+static int dcb_set_attribute_attr_cb(const struct nlattr *attr, void *data)
+{
+	uint16_t len;
+	uint8_t err;
+
+	if (mnl_attr_get_type(attr) != DCB_ATTR_IEEE)
+		return MNL_CB_OK;
+
+	len = mnl_attr_get_payload_len(attr);
+	if (len != 1) {
+		fprintf(stderr, "Response attribute expected to have size 1, not %d\n", len);
+		return MNL_CB_ERROR;
+	}
+
+	err = mnl_attr_get_u8(attr);
+	if (err) {
+		fprintf(stderr, "Error when attempting to set attribute: %s\n",
+			strerror(err));
+		return MNL_CB_ERROR;
+	}
+
+	return MNL_CB_STOP;
+}
+
+static int dcb_set_attribute_cb(const struct nlmsghdr *nlh, void *data)
+{
+	return mnl_attr_parse(nlh, sizeof(struct dcbmsg), dcb_set_attribute_attr_cb, data);
+}
+
+static int dcb_talk(struct dcb *dcb, struct nlmsghdr *nlh, mnl_cb_t cb, void *data)
+{
+	int ret;
+
+	ret = mnl_socket_sendto(dcb->nl, nlh, nlh->nlmsg_len);
+	if (ret < 0) {
+		perror("mnl_socket_sendto");
+		return -1;
+	}
+
+	return mnlu_socket_recv_run(dcb->nl, nlh->nlmsg_seq, dcb->buf, MNL_SOCKET_BUFFER_SIZE,
+				    cb, data);
+}
+
+static struct nlmsghdr *dcb_prepare(struct dcb *dcb, const char *dev,
+				    uint32_t nlmsg_type, uint8_t dcb_cmd)
+{
+	struct dcbmsg dcbm = {
+		.cmd = dcb_cmd,
+	};
+	struct nlmsghdr *nlh;
+
+	nlh = mnlu_msg_prepare(dcb->buf, nlmsg_type, NLM_F_REQUEST, &dcbm, sizeof(dcbm));
+	mnl_attr_put_strz(nlh, DCB_ATTR_IFNAME, dev);
+	return nlh;
+}
+
+int dcb_get_attribute(struct dcb *dcb, const char *dev, int attr, void *data, size_t data_len)
+{
+	struct dcb_get_attribute ga;
+	struct nlmsghdr *nlh;
+	int ret;
+
+	nlh = dcb_prepare(dcb, dev, RTM_GETDCB, DCB_CMD_IEEE_GET);
+
+	ga = (struct dcb_get_attribute) {
+		.dcb = dcb,
+		.attr = attr,
+		.data = data,
+		.data_len = data_len,
+	};
+	ret = dcb_talk(dcb, nlh, dcb_get_attribute_cb, &ga);
+	if (ret) {
+		perror("Attribute read");
+		return ret;
+	}
+	return 0;
+}
+
+int dcb_set_attribute(struct dcb *dcb, const char *dev, int attr, const void *data, size_t data_len)
+{
+	struct nlmsghdr *nlh;
+	struct nlattr *nest;
+	int ret;
+
+	nlh = dcb_prepare(dcb, dev, RTM_GETDCB, DCB_CMD_IEEE_SET);
+
+	nest = mnl_attr_nest_start(nlh, DCB_ATTR_IEEE);
+	mnl_attr_put(nlh, attr, data_len, data);
+	mnl_attr_nest_end(nlh, nest);
+
+	ret = dcb_talk(dcb, nlh, dcb_set_attribute_cb, NULL);
+	if (ret) {
+		perror("Attribute write");
+		return ret;
+	}
+	return 0;
+}
+
+void dcb_print_array_num(FILE *fp, const __u8 *array, size_t size)
+{
+	SPRINT_BUF(b);
+	size_t i;
+
+	for (i = 0; i < size; i++) {
+		snprintf(b, sizeof(b), "%zd:%%d ", i);
+		print_uint(PRINT_ANY, NULL, b, array[i]);
+	}
+}
+
+void dcb_print_array_kw(FILE *fp, const __u8 *array, size_t array_size,
+			const char *const kw[], size_t kw_size)
+{
+	SPRINT_BUF(b);
+	size_t i;
+
+	for (i = 0; i < array_size; i++) {
+		__u8 emt = array[i];
+
+		snprintf(b, sizeof(b), "%zd:%%s ", i);
+		if (emt < kw_size && kw[emt])
+			print_string(PRINT_ANY, NULL, b, kw[emt]);
+		else
+			print_string(PRINT_ANY, NULL, b, "???");
+	}
+}
+
+void dcb_print_named_array(FILE *fp, const char *fp_name, const char *json_name,
+			   const __u8 *array, size_t size,
+			   void (*print_array)(FILE *, const __u8 *, size_t))
+{
+	open_json_array(PRINT_JSON, json_name);
+	print_string(PRINT_FP, NULL, "%s ", fp_name);
+	print_array(fp, array, size);
+	close_json_array(PRINT_JSON, json_name);
+}
+
+int dcb_parse_mapping(__u32 key, __u8 value, __u8 max_value, __u8 *array,
+		      const char *what_key, const char *what_value)
+{
+	bool is_all = key == (__u32) -1;
+
+	if (!is_all && key >= IEEE_8021QAZ_MAX_TCS) {
+		fprintf(stderr, "In %s:%s mapping, %s is expected to be 0..%d\n",
+			what_key, what_value, what_key, IEEE_8021QAZ_MAX_TCS - 1);
+		return -EINVAL;
+	}
+
+	if (value > max_value) {
+		fprintf(stderr, "In %s:%s mapping, %s is expected to be 0..%d\n",
+			what_key, what_value, what_value, max_value);
+		return -EINVAL;
+	}
+
+	if (is_all) {
+		for (key = 0; key < IEEE_8021QAZ_MAX_TCS; key++)
+			array[key] = value;
+	} else {
+		array[key] = value;
+	}
+
+	return 0;
+}
+
+int dcb_cmd_parse_dev(struct dcb *dcb, int argc, char **argv,
+		      int (*and_then)(struct dcb *dcb, const char *dev,
+				      int argc, char **argv),
+		      void (*help)(void))
+{
+	const char *dev;
+
+	if (!argc || matches(*argv, "help") == 0) {
+		help();
+		return 0;
+	} else if (matches(*argv, "dev") == 0) {
+		NEXT_ARG();
+		dev = *argv;
+		if (check_ifname(dev)) {
+			invarg("not a valid ifname", *argv);
+			return -EINVAL;
+		}
+		NEXT_ARG_FWD();
+		return and_then(dcb, dev, argc, argv);
+	} else {
+		fprintf(stderr, "Expected `dev DEV', not `%s'", *argv);
+		help();
+		return -EINVAL;
+	}
+}
+
+static void dcb_help(void)
+{
+	fprintf(stderr,
+		"Usage: dcb [ OPTIONS ] OBJECT { COMMAND | help }\n"
+		"       dcb [ -f[orce] ] -b[atch] filename -N[etns] netnsname\n"
+		"where  OBJECT :=\n"
+		"       OPTIONS := { -V[ersion] | -j[son] | -p[retty] | -v[erbose] }\n");
+}
+
+static int dcb_cmd(struct dcb *dcb, int argc, char **argv)
+{
+	if (!argc || matches(*argv, "help") == 0) {
+		dcb_help();
+		return 0;
+	}
+
+	fprintf(stderr, "Object \"%s\" is unknown\n", *argv);
+	return -ENOENT;
+}
+
+static int dcb_batch_cmd(int argc, char *argv[], void *data)
+{
+	struct dcb *dcb = data;
+
+	return dcb_cmd(dcb, argc, argv);
+}
+
+static int dcb_batch(struct dcb *dcb, const char *name, bool force)
+{
+	return do_batch(name, force, dcb_batch_cmd, dcb);
+}
+
+int main(int argc, char **argv)
+{
+	static const struct option long_options[] = {
+		{ "Version",		no_argument,		NULL, 'V' },
+		{ "force",		no_argument,		NULL, 'f' },
+		{ "batch",		required_argument,	NULL, 'b' },
+		{ "json",		no_argument,		NULL, 'j' },
+		{ "pretty",		no_argument,		NULL, 'p' },
+		{ "Netns",		required_argument,	NULL, 'N' },
+		{ NULL, 0, NULL, 0 }
+	};
+	const char *batch_file = NULL;
+	bool force = false;
+	struct dcb *dcb;
+	int opt;
+	int err;
+	int ret;
+
+	dcb = dcb_alloc();
+	if (!dcb) {
+		fprintf(stderr, "Failed to allocate memory for dcb\n");
+		return EXIT_FAILURE;
+	}
+
+	while ((opt = getopt_long(argc, argv, "Vfb:njpvN:",
+				  long_options, NULL)) >= 0) {
+
+		switch (opt) {
+		case 'V':
+			printf("dcb utility, iproute2-%s\n", version);
+			ret = EXIT_SUCCESS;
+			goto dcb_free;
+		case 'f':
+			force = true;
+			break;
+		case 'b':
+			batch_file = optarg;
+			break;
+		case 'j':
+			dcb->json_output = true;
+			break;
+		case 'p':
+			pretty = true;
+			break;
+		case 'N':
+			if (netns_switch(optarg)) {
+				ret = EXIT_FAILURE;
+				goto dcb_free;
+			}
+			break;
+		default:
+			fprintf(stderr, "Unknown option.\n");
+			dcb_help();
+			ret = EXIT_FAILURE;
+			goto dcb_free;
+		}
+	}
+
+	argc -= optind;
+	argv += optind;
+
+	err = dcb_init(dcb);
+	if (err) {
+		ret = EXIT_FAILURE;
+		goto dcb_free;
+	}
+
+	if (batch_file)
+		err = dcb_batch(dcb, batch_file, force);
+	else
+		err = dcb_cmd(dcb, argc, argv);
+
+	if (err) {
+		ret = EXIT_FAILURE;
+		goto dcb_fini;
+	}
+
+	ret = EXIT_SUCCESS;
+
+dcb_fini:
+	dcb_fini(dcb);
+dcb_free:
+	dcb_free(dcb);
+
+	return ret;
+}
diff --git a/dcb/dcb.h b/dcb/dcb.h
new file mode 100644
index 000000000000..1d31a0f94652
--- /dev/null
+++ b/dcb/dcb.h
@@ -0,0 +1,35 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __DCB_H__
+#define __DCB_H__ 1
+
+#include <stdbool.h>
+#include <stddef.h>
+
+/* dcb.c */
+
+struct dcb {
+	char *buf;
+	struct mnl_socket *nl;
+	bool json_output;
+};
+
+int dcb_parse_mapping(__u32 key, __u8 value, __u8 max_value, __u8 *array,
+		      const char *what_key, const char *what_value);
+int dcb_cmd_parse_dev(struct dcb *dcb, int argc, char **argv,
+		      int (*and_then)(struct dcb *dcb, const char *dev,
+				      int argc, char **argv),
+		      void (*help)(void));
+
+int dcb_get_attribute(struct dcb *dcb, const char *dev, int attr,
+		      void *data, size_t data_len);
+int dcb_set_attribute(struct dcb *dcb, const char *dev, int attr,
+		      const void *data, size_t data_len);
+
+void dcb_print_named_array(FILE *fp, const char *fp_name, const char *json_name,
+			   const __u8 *array, size_t size,
+			   void (*print_array)(FILE *, const __u8 *, size_t));
+void dcb_print_array_num(FILE *fp, const __u8 *array, size_t size);
+void dcb_print_array_kw(FILE *fp, const __u8 *array, size_t array_size,
+			const char *const kw[], size_t kw_size);
+
+#endif /* __DCB_H__ */
diff --git a/man/man8/dcb.8 b/man/man8/dcb.8
new file mode 100644
index 000000000000..25ddf204d60e
--- /dev/null
+++ b/man/man8/dcb.8
@@ -0,0 +1,103 @@
+.TH DCB 8 "19 October 2020" "iproute2" "Linux"
+.SH NAME
+dcb \- show / manipulate DCB (Data Center Bridging) settings
+.SH SYNOPSIS
+.sp
+.ad l
+.in +8
+
+.ti -8
+.B dcb
+.RB "[ " -force " ] "
+.BI "-batch " filename
+.sp
+
+.ti -8
+.B dcb
+.RI "[ " OPTIONS " ] "
+.B help
+.sp
+
+.SH OPTIONS
+
+.TP
+.BR "\-V" , " --Version"
+Print the version of the
+.B dcb
+utility and exit.
+
+.TP
+.BR "\-b", " \-batch " <FILENAME>
+Read commands from provided file or standard input and invoke them. First
+failure will cause termination of dcb.
+
+.TP
+.B \-force
+Don't terminate dcb on errors in batch mode. If there were any errors during
+execution of the commands, the application return code will be non zero.
+
+.TP
+.BR "\-j" , " --json"
+Generate JSON output.
+
+.TP
+.BR "\-p" , " --pretty"
+When combined with -j generate a pretty JSON output.
+
+.SH OBJECTS
+
+.SH COMMANDS
+
+A \fICOMMAND\fR specifies the action to perform on the object. The set of
+possible actions depends on the object type. As a rule, it is possible to
+.B show
+objects and to invoke topical
+.B help,
+which prints a list of available commands and argument syntax conventions.
+
+.SH ARRAY PARAMETERS
+
+Like commands, specification of parameters is in the domain of individual
+objects (and their commands) as well. However, much of the DCB interface
+revolves around arrays of fixed size that specify one value per some key, such
+as per traffic class or per priority. There is therefore a single syntax for
+adjusting elements of these arrays. It consists of a series of
+\fIKEY\fB:\fIVALUE\fR pairs, where the meaning of the individual keys and values
+depends on the parameter.
+
+The elements are evaluated in order from left to right, and the latter ones
+override the earlier ones. The elements that are not specified on the command
+line are queried from the kernel and their current value is retained.
+
+As an example, take a made-up parameter tc-juju, which can be set to charm
+traffic in a given TC with either good luck or bad luck. \fIKEY\fR can therefore
+be 0..7 (as is usual for TC numbers in DCB), and \fIVALUE\fR either of
+\fBnone\fR, \fBgood\fR, and \fBbad\fR. An example of changing a juju value of
+TCs 0 and 7, while leaving all other intact, would then be:
+
+.P
+# dcb foo set dev eth0 tc-juju 0:good 7:bad
+
+A special key, \fBall\fR, is recognized which sets the same value to all array
+elements. This can be combined with the usual single-element syntax. E.g. in the
+following, the juju or all keys is set to \fBnone\fR, except 0 and 7, which have
+other values:
+
+.P
+# dcb foo set dev eth0 tc-juju all:none 0:good 7:bad
+
+.SH EXIT STATUS
+Exit status is 0 if command was successful or a positive integer upon failure.
+
+.SH SEE ALSO
+.BR dcb-ets (8)
+.br
+
+.SH REPORTING BUGS
+Report any bugs to the Network Developers mailing list
+.B <netdev@vger.kernel.org>
+where the development and maintenance is primarily done.
+You do not have to be subscribed to the list to send a message there.
+
+.SH AUTHOR
+Petr Machata <me@pmachata.org>
-- 
2.25.1

[PATCH iproute2-next v2 11/11] dcb: Add a subtool for the DCB ETS object

[Petr Machata]

ETS, for "Enhanced Transmission Selection", is a set of configurations that
permit configuration of mapping of priorities to traffic classes, traffic
selection algorithm to use per traffic class, bandwidth allocation, etc.

Add a dcb subtool to allow showing and tweaking of individual ETS
configuration options. For example:

    # dcb ets show dev eni1np1
    willing on ets_cap 8 cbs off
    tc-bw 0:0 1:0 2:0 3:0 4:100 5:0 6:0 7:0
    pg-bw 0:0 1:0 2:0 3:0 4:0 5:0 6:0 7:0
    tc-tsa 0:strict 1:strict 2:strict 3:strict 4:ets 5:strict 6:strict 7:strict
    prio-tc 0:1 1:3 2:5 3:0 4:0 5:0 6:0 7:0
    reco-tc-bw 0:0 1:0 2:0 3:0 4:0 5:0 6:0 7:0
    reco-tc-tsa 0:strict 1:strict 2:strict 3:strict 4:strict 5:strict 6:strict 7:strict
    reco-prio-tc 0:0 1:0 2:0 3:0 4:0 5:0 6:0 7:0

Signed-off-by: Petr Machata <me@pmachata.org>
---
 dcb/Makefile       |   2 +-
 dcb/dcb.c          |   4 +-
 dcb/dcb.h          |   4 +
 dcb/dcb_ets.c      | 430 +++++++++++++++++++++++++++++++++++++++++++++
 man/man8/dcb-ets.8 | 185 +++++++++++++++++++
 man/man8/dcb.8     |  11 ++
 6 files changed, 634 insertions(+), 2 deletions(-)
 create mode 100644 dcb/dcb_ets.c
 create mode 100644 man/man8/dcb-ets.8

diff --git a/dcb/Makefile b/dcb/Makefile
index 9966c8f0bfa4..895817163562 100644
--- a/dcb/Makefile
+++ b/dcb/Makefile
@@ -5,7 +5,7 @@ TARGETS :=
 
 ifeq ($(HAVE_MNL),y)
 
-DCBOBJ = dcb.o
+DCBOBJ = dcb.o dcb_ets.o
 TARGETS += dcb
 
 endif
diff --git a/dcb/dcb.c b/dcb/dcb.c
index 26c1f91e815a..a776aa542f93 100644
--- a/dcb/dcb.c
+++ b/dcb/dcb.c
@@ -286,7 +286,7 @@ static void dcb_help(void)
 	fprintf(stderr,
 		"Usage: dcb [ OPTIONS ] OBJECT { COMMAND | help }\n"
 		"       dcb [ -f[orce] ] -b[atch] filename -N[etns] netnsname\n"
-		"where  OBJECT :=\n"
+		"where  OBJECT := ets\n"
 		"       OPTIONS := { -V[ersion] | -j[son] | -p[retty] | -v[erbose] }\n");
 }
 
@@ -295,6 +295,8 @@ static int dcb_cmd(struct dcb *dcb, int argc, char **argv)
 	if (!argc || matches(*argv, "help") == 0) {
 		dcb_help();
 		return 0;
+	} else if (matches(*argv, "ets") == 0) {
+		return dcb_cmd_ets(dcb, argc - 1, argv + 1);
 	}
 
 	fprintf(stderr, "Object \"%s\" is unknown\n", *argv);
diff --git a/dcb/dcb.h b/dcb/dcb.h
index 1d31a0f94652..9b46e09178be 100644
--- a/dcb/dcb.h
+++ b/dcb/dcb.h
@@ -32,4 +32,8 @@ void dcb_print_array_num(FILE *fp, const __u8 *array, size_t size);
 void dcb_print_array_kw(FILE *fp, const __u8 *array, size_t array_size,
 			const char *const kw[], size_t kw_size);
 
+/* dcb_ets.c */
+
+int dcb_cmd_ets(struct dcb *dcb, int argc, char **argv);
+
 #endif /* __DCB_H__ */
diff --git a/dcb/dcb_ets.c b/dcb/dcb_ets.c
new file mode 100644
index 000000000000..1af8dce8100d
--- /dev/null
+++ b/dcb/dcb_ets.c
@@ -0,0 +1,430 @@
+// SPDX-License-Identifier: GPL-2.0+
+
+#include <errno.h>
+#include <stdio.h>
+#include <linux/dcbnl.h>
+
+#include "dcb.h"
+#include "utils.h"
+
+static void dcb_ets_help_set(void)
+{
+	fprintf(stderr,
+		"Usage: dcb ets set dev STRING\n"
+		"           [ willing { on | off } ]\n"
+		"           [ { tc-tsa | reco-tc-tsa } TSA-MAP ]\n"
+		"           [ { pg-bw | tc-bw | reco-tc-bw } BW-MAP ]\n"
+		"           [ { prio-tc | reco-prio-tc } PRIO-MAP ]\n"
+		"\n"
+		" where TSA-MAP := [ TSA-MAP ] TSA-MAPPING\n"
+		"       TSA-MAPPING := { all | TC }:{ strict | cbs | ets | vendor }\n"
+		"       BW-MAP := [ BW-MAP ] BW-MAPPING\n"
+		"       BW-MAPPING := { all | TC }:INTEGER\n"
+		"       PRIO-MAP := [ PRIO-MAP ] PRIO-MAPPING\n"
+		"       PRIO-MAPPING := { all | PRIO }:TC\n"
+		"       TC := { 0 .. 7 }\n"
+		"       PRIO := { 0 .. 7 }\n"
+		"\n"
+	);
+}
+
+static void dcb_ets_help_show(void)
+{
+	fprintf(stderr,
+		"Usage: dcb ets show dev STRING\n"
+		"           [ willing | ets-cap | cbs | tc-tsa | reco-tc-tsa |\n"
+		"             pg-bw | tc-bw | reco-tc-bw | prio-tc |\n"
+		"             reco-prio-tc ]\n"
+		"\n"
+	);
+}
+
+static void dcb_ets_help(void)
+{
+	fprintf(stderr,
+		"Usage: dcb ets help\n"
+		"\n"
+	);
+	dcb_ets_help_show();
+	dcb_ets_help_set();
+}
+
+static const char *const tsa_names[] = {
+	[IEEE_8021QAZ_TSA_STRICT] = "strict",
+	[IEEE_8021QAZ_TSA_CB_SHAPER] = "cbs",
+	[IEEE_8021QAZ_TSA_ETS] = "ets",
+	[IEEE_8021QAZ_TSA_VENDOR] = "vendor",
+};
+
+static int dcb_ets_parse_mapping_tc_tsa(__u32 key, char *value, void *data)
+{
+	__u8 tsa;
+	int ret;
+
+	tsa = parse_one_of("TSA", value, tsa_names, ARRAY_SIZE(tsa_names), &ret);
+	if (ret)
+		return ret;
+
+	return dcb_parse_mapping(key, tsa, -1, data, "TC", "TSA");
+}
+
+static int dcb_ets_parse_mapping_tc_int(__u32 key, char *value, __u8 max_value, __u8 *array,
+					const char *what_key, const char *what_value)
+{
+	__u8 int_value;
+
+	if (get_u8(&int_value, value, 0))
+		return -EINVAL;
+
+	return dcb_parse_mapping(key, int_value, max_value, array, what_key, what_value);
+}
+
+static int dcb_ets_parse_mapping_tc_bw(__u32 key, char *value, void *data)
+{
+	return dcb_ets_parse_mapping_tc_int(key, value, 100, data, "TC", "BW");
+}
+
+static int dcb_ets_parse_mapping_prio_tc(unsigned int key, char *value, void *data)
+{
+	return dcb_ets_parse_mapping_tc_int(key, value, IEEE_8021QAZ_MAX_TCS, data, "PRIO", "TC");
+}
+
+static void dcb_print_array_tsa(FILE *fp, const __u8 *array, size_t size)
+{
+	dcb_print_array_kw(fp, array, size, tsa_names, ARRAY_SIZE(tsa_names));
+}
+
+static void dcb_ets_print_willing(FILE *fp, const struct ieee_ets *ets)
+{
+	print_on_off_bool(fp, "willing", ets->willing);
+}
+
+static void dcb_ets_print_ets_cap(FILE *fp, const struct ieee_ets *ets)
+{
+	print_uint(PRINT_ANY, "ets_cap", "ets_cap %d ", ets->ets_cap);
+}
+
+static void dcb_ets_print_cbs(FILE *fp, const struct ieee_ets *ets)
+{
+	print_on_off_bool(fp, "cbs", ets->cbs);
+}
+
+static void dcb_ets_print_tc_bw(FILE *fp, const struct ieee_ets *ets)
+{
+	dcb_print_named_array(fp, "tc-bw", "tc_bw",
+			      ets->tc_tx_bw, ARRAY_SIZE(ets->tc_tx_bw),
+			      dcb_print_array_num);
+}
+
+static void dcb_ets_print_pg_bw(FILE *fp, const struct ieee_ets *ets)
+{
+	dcb_print_named_array(fp, "pg-bw", "pg_bw",
+			      ets->tc_rx_bw, ARRAY_SIZE(ets->tc_rx_bw),
+			      dcb_print_array_num);
+}
+
+static void dcb_ets_print_tc_tsa(FILE *fp, const struct ieee_ets *ets)
+{
+	dcb_print_named_array(fp, "tc-tsa", "tc_tsa",
+			      ets->tc_tsa, ARRAY_SIZE(ets->tc_tsa),
+			      dcb_print_array_tsa);
+}
+
+static void dcb_ets_print_prio_tc(FILE *fp, const struct ieee_ets *ets)
+{
+	dcb_print_named_array(fp, "prio-tc", "prio_tc",
+			      ets->prio_tc, ARRAY_SIZE(ets->prio_tc),
+			      dcb_print_array_num);
+}
+
+static void dcb_ets_print_reco_tc_bw(FILE *fp, const struct ieee_ets *ets)
+{
+	dcb_print_named_array(fp, "reco-tc-bw", "reco_tc_bw",
+			      ets->tc_reco_bw, ARRAY_SIZE(ets->tc_reco_bw),
+			      dcb_print_array_num);
+}
+
+static void dcb_ets_print_reco_tc_tsa(FILE *fp, const struct ieee_ets *ets)
+{
+	dcb_print_named_array(fp, "reco-tc-tsa", "reco_tc_tsa",
+			      ets->tc_reco_tsa, ARRAY_SIZE(ets->tc_reco_tsa),
+			      dcb_print_array_tsa);
+}
+
+static void dcb_ets_print_reco_prio_tc(FILE *fp, const struct ieee_ets *ets)
+{
+	dcb_print_named_array(fp, "reco-prio-tc", "reco_prio_tc",
+			      ets->reco_prio_tc, ARRAY_SIZE(ets->reco_prio_tc),
+			      dcb_print_array_num);
+}
+
+static void dcb_ets_print(FILE *fp, const struct ieee_ets *ets)
+{
+	dcb_ets_print_willing(fp, ets);
+	dcb_ets_print_ets_cap(fp, ets);
+	dcb_ets_print_cbs(fp, ets);
+	print_nl();
+
+	dcb_ets_print_tc_bw(fp, ets);
+	print_nl();
+
+	dcb_ets_print_pg_bw(fp, ets);
+	print_nl();
+
+	dcb_ets_print_tc_tsa(fp, ets);
+	print_nl();
+
+	dcb_ets_print_prio_tc(fp, ets);
+	print_nl();
+
+	dcb_ets_print_reco_tc_bw(fp, ets);
+	print_nl();
+
+	dcb_ets_print_reco_tc_tsa(fp, ets);
+	print_nl();
+
+	dcb_ets_print_reco_prio_tc(fp, ets);
+	print_nl();
+}
+
+static int dcb_ets_get(struct dcb *dcb, const char *dev, struct ieee_ets *ets)
+{
+	return dcb_get_attribute(dcb, dev, DCB_ATTR_IEEE_ETS, ets, sizeof(*ets));
+}
+
+static int dcb_ets_validate_bw(const __u8 bw[], const __u8 tsa[], const char *what)
+{
+	bool has_ets = false;
+	unsigned int total = 0;
+	unsigned int tc;
+
+	for (tc = 0; tc < IEEE_8021QAZ_MAX_TCS; tc++) {
+		if (tsa[tc] == IEEE_8021QAZ_TSA_ETS) {
+			has_ets = true;
+			break;
+		}
+	}
+
+	/* TC bandwidth is only intended for ETS, but 802.1Q-2018 only requires
+	 * that the sum be 100, and individual entries 0..100. It explicitly
+	 * notes that non-ETS TCs can have non-0 TC bandwidth during
+	 * reconfiguration.
+	 */
+	for (tc = 0; tc < IEEE_8021QAZ_MAX_TCS; tc++) {
+		if (bw[tc] > 100) {
+			fprintf(stderr, "%d%% for TC %d of %s is not a valid bandwidth percentage, expected 0..100%%\n",
+				bw[tc], tc, what);
+			return -EINVAL;
+		}
+		total += bw[tc];
+	}
+
+	/* This is what 802.1Q-2018 requires. */
+	if (total == 100)
+		return 0;
+
+	/* But this requirement does not make sense for all-strict
+	 * configurations. Anything else than 0 does not make sense: either BW
+	 * has not been reconfigured for the all-strict allocation yet, at which
+	 * point we expect sum of 100. Or it has already been reconfigured, at
+	 * which point accept 0.
+	 */
+	if (!has_ets && total == 0)
+		return 0;
+
+	fprintf(stderr, "Bandwidth percentages in %s sum to %d%%, expected %d%%\n",
+		what, total, has_ets ? 100 : 0);
+	return -EINVAL;
+}
+
+static int dcb_ets_set(struct dcb *dcb, const char *dev, const struct ieee_ets *ets)
+{
+	/* Do not validate pg-bw, which is not standard and has unclear
+	 * meaning.
+	 */
+	if (dcb_ets_validate_bw(ets->tc_tx_bw, ets->tc_tsa, "tc-bw") ||
+	    dcb_ets_validate_bw(ets->tc_reco_bw, ets->tc_reco_tsa, "reco-tc-bw"))
+		return -EINVAL;
+
+	return dcb_set_attribute(dcb, dev, DCB_ATTR_IEEE_ETS, ets, sizeof(*ets));
+}
+
+static int dcb_cmd_ets_set(struct dcb *dcb, const char *dev, int argc, char **argv)
+{
+	struct ieee_ets ets;
+	int ret;
+
+	if (!argc) {
+		dcb_ets_help_set();
+		return 0;
+	}
+
+	ret = dcb_ets_get(dcb, dev, &ets);
+	if (ret)
+		return ret;
+
+	do {
+		if (matches(*argv, "help") == 0) {
+			dcb_ets_help_set();
+			return 0;
+		} else if (matches(*argv, "willing") == 0) {
+			NEXT_ARG();
+			ets.willing = parse_on_off("willing", *argv, &ret);
+			if (ret)
+				return ret;
+		} else if (matches(*argv, "tc-tsa") == 0) {
+			NEXT_ARG();
+			ret = parse_mapping(&argc, &argv, true, &dcb_ets_parse_mapping_tc_tsa,
+					    ets.tc_tsa);
+			if (ret) {
+				fprintf(stderr, "Invalid tc-tsa mapping %s\n", *argv);
+				return ret;
+			}
+			continue;
+		} else if (matches(*argv, "reco-tc-tsa") == 0) {
+			NEXT_ARG();
+			ret = parse_mapping(&argc, &argv, true, &dcb_ets_parse_mapping_tc_tsa,
+					    ets.tc_reco_tsa);
+			if (ret) {
+				fprintf(stderr, "Invalid reco-tc-tsa mapping %s\n", *argv);
+				return ret;
+			}
+			continue;
+		} else if (matches(*argv, "tc-bw") == 0) {
+			NEXT_ARG();
+			ret = parse_mapping(&argc, &argv, true, &dcb_ets_parse_mapping_tc_bw,
+					    ets.tc_tx_bw);
+			if (ret) {
+				fprintf(stderr, "Invalid tc-bw mapping %s\n", *argv);
+				return ret;
+			}
+			continue;
+		} else if (matches(*argv, "pg-bw") == 0) {
+			NEXT_ARG();
+			ret = parse_mapping(&argc, &argv, true, &dcb_ets_parse_mapping_tc_bw,
+					    ets.tc_rx_bw);
+			if (ret) {
+				fprintf(stderr, "Invalid pg-bw mapping %s\n", *argv);
+				return ret;
+			}
+			continue;
+		} else if (matches(*argv, "reco-tc-bw") == 0) {
+			NEXT_ARG();
+			ret = parse_mapping(&argc, &argv, true, &dcb_ets_parse_mapping_tc_bw,
+					    ets.tc_reco_bw);
+			if (ret) {
+				fprintf(stderr, "Invalid reco-tc-bw mapping %s\n", *argv);
+				return ret;
+			}
+			continue;
+		} else if (matches(*argv, "prio-tc") == 0) {
+			NEXT_ARG();
+			ret = parse_mapping(&argc, &argv, true, &dcb_ets_parse_mapping_prio_tc,
+					    ets.prio_tc);
+			if (ret) {
+				fprintf(stderr, "Invalid prio-tc mapping %s\n", *argv);
+				return ret;
+			}
+			continue;
+		} else if (matches(*argv, "reco-prio-tc") == 0) {
+			NEXT_ARG();
+			ret = parse_mapping(&argc, &argv, true, &dcb_ets_parse_mapping_prio_tc,
+					    ets.reco_prio_tc);
+			if (ret) {
+				fprintf(stderr, "Invalid reco-prio-tc mapping %s\n", *argv);
+				return ret;
+			}
+			continue;
+		} else {
+			fprintf(stderr, "What is \"%s\"?\n", *argv);
+			dcb_ets_help_set();
+			return -EINVAL;
+		}
+
+		NEXT_ARG_FWD();
+	} while (argc > 0);
+
+	return dcb_ets_set(dcb, dev, &ets);
+}
+
+static int dcb_cmd_ets_show(struct dcb *dcb, const char *dev, int argc, char **argv)
+{
+	struct ieee_ets ets;
+	int ret;
+
+	ret = dcb_ets_get(dcb, dev, &ets);
+	if (ret)
+		return ret;
+
+	open_json_object(NULL);
+
+	if (!argc) {
+		dcb_ets_print(stdout, &ets);
+		goto out;
+	}
+
+	do {
+		if (matches(*argv, "help") == 0) {
+			dcb_ets_help();
+			return 0;
+		} else if (matches(*argv, "willing") == 0) {
+			dcb_ets_print_willing(stdout, &ets);
+			print_nl();
+		} else if (matches(*argv, "ets-cap") == 0) {
+			dcb_ets_print_ets_cap(stdout, &ets);
+			print_nl();
+		} else if (matches(*argv, "cbs") == 0) {
+			dcb_ets_print_cbs(stdout, &ets);
+			print_nl();
+		} else if (matches(*argv, "tc-tsa") == 0) {
+			dcb_ets_print_tc_tsa(stdout, &ets);
+			print_nl();
+		} else if (matches(*argv, "reco-tc-tsa") == 0) {
+			dcb_ets_print_reco_tc_tsa(stdout, &ets);
+			print_nl();
+		} else if (matches(*argv, "tc-bw") == 0) {
+			dcb_ets_print_tc_bw(stdout, &ets);
+			print_nl();
+		} else if (matches(*argv, "pg-bw") == 0) {
+			dcb_ets_print_pg_bw(stdout, &ets);
+			print_nl();
+		} else if (matches(*argv, "reco-tc-bw") == 0) {
+			dcb_ets_print_reco_tc_bw(stdout, &ets);
+			print_nl();
+		} else if (matches(*argv, "prio-tc") == 0) {
+			dcb_ets_print_prio_tc(stdout, &ets);
+			print_nl();
+		} else if (matches(*argv, "reco-prio-tc") == 0) {
+			dcb_ets_print_reco_prio_tc(stdout, &ets);
+			print_nl();
+		} else {
+			fprintf(stderr, "What is \"%s\"?\n", *argv);
+			dcb_ets_help();
+			return -EINVAL;
+		}
+
+		NEXT_ARG_FWD();
+	} while (argc > 0);
+
+out:
+	close_json_object();
+	return 0;
+}
+
+int dcb_cmd_ets(struct dcb *dcb, int argc, char **argv)
+{
+	if (!argc || matches(*argv, "help") == 0) {
+		dcb_ets_help();
+		return 0;
+	} else if (matches(*argv, "show") == 0) {
+		NEXT_ARG_FWD();
+		return dcb_cmd_parse_dev(dcb, argc, argv, dcb_cmd_ets_show, dcb_ets_help_show);
+	} else if (matches(*argv, "set") == 0) {
+		NEXT_ARG_FWD();
+		return dcb_cmd_parse_dev(dcb, argc, argv, dcb_cmd_ets_set, dcb_ets_help_set);
+	} else {
+		fprintf(stderr, "What is \"%s\"?\n", *argv);
+		dcb_ets_help();
+		return -EINVAL;
+	}
+}
diff --git a/man/man8/dcb-ets.8 b/man/man8/dcb-ets.8
new file mode 100644
index 000000000000..5286199f180f
--- /dev/null
+++ b/man/man8/dcb-ets.8
@@ -0,0 +1,185 @@
+.TH DCB-ETS 8 "19 October 2020" "iproute2" "Linux"
+.SH NAME
+dcb-ets \- show / manipulate ETS (Enhanced Transmission Selection) settings of
+the DCB (Data Center Bridging) subsystem
+.SH SYNOPSIS
+.sp
+.ad l
+.in +8
+
+.ti -8
+.B dcb
+.RI "[ " OPTIONS " ] "
+.B ets
+.RI "{ " COMMAND " | " help " }"
+.sp
+
+.ti -8
+.B dcb ets show dev
+.RI DEV
+.B "[ {" willing "|" ets-cap "|" cbs "|" tc-tsa "|" reco-tc-tsa "|"
+.B pg-bw "|" tc-bw "|" reco-tc-bw "|" prio-tc "|"
+.B reco-prio-tc "} ]"
+
+.ti -8
+.B dcb ets set dev
+.RI DEV
+.B "[" willing "{" on "|" off "} ]"
+.B "[ {" tc-tsa "|" reco-tc-tsa "}" \fITSA-MAP\fB "]"
+.B "[ {" pg-bw "|" tc-bw "|" reco-tc-bw "}" \fIBW-MAP\fB "]"
+.B "[ {" prio-tc "|" reco-prio-tc "}" \fIPRIO-MAP\fB "]"
+
+.ti -8
+.IR TSA-MAP " := [ " TSA-MAP " ] " TSA-MAPPING
+
+.ti -8
+.IR TSA-MAPPING " := { " TC " | " \fBall " }" \fB: "{ " \fBstrict\fR " | "
+.IR \fBcbs\fR " | " \fBets\fR " | " \fBvendor\fR " }"
+
+.ti -8
+.IR BW-MAP " := [ " BW-MAP " ] " BW-MAPPING
+
+.ti -8
+.IR BW-MAPPING " := { " TC " | " \fBall " }" \fB:\fIINTEGER\fR
+
+.ti -8
+.IR PRIO-MAP " := [ " PRIO-MAP " ] " PRIO-MAPPING
+
+.ti -8
+.IR PRIO-MAPPING " := { " PRIO " | " \fBall " }" \fB:\fITC\fR
+
+.ti -8
+.IR TC " := { " \fB0\fR " .. " \fB7\fR " }"
+
+.ti -8
+.IR PRIO " := { " \fB0\fR " .. " \fB7\fR " }"
+
+
+.SH DESCRIPTION
+
+.B dcb ets
+is used to configure Enhanced Transmission Selection attributes through Linux
+DCB (Data Center Bridging) interface. ETS permits configuration of mapping of
+priorities to traffic classes, traffic selection algorithm to use per traffic
+class, bandwidth allocation, etc.
+
+Two DCB TLVs are related to the ETS feature: a configuration and recommendation
+values. Recommendation values are named with a prefix
+.B reco-,
+while the configuration ones have plain names.
+
+.SH PARAMETERS
+
+For read-write parameters, the following describes only the write direction,
+i.e. as used with the \fBset\fR command. For the \fBshow\fR command, the
+parameter name is to be used as a simple keyword without further arguments. This
+instructs the tool to show the value of a given parameter. When no parameters
+are given, the tool shows the complete ETS configuration.
+
+.TP
+.B ets-cap
+A read-only property that shows the number of supported ETS traffic classes.
+
+.TP
+.B cbs
+A read-only property that is enabled if the driver and the hardware support the
+CBS Transmission Selection Algorithm.
+
+.TP
+.B willing \fR{ \fBon\fR | \fBoff\fR }
+Whether local host should accept configuration from peer TLVs.
+
+.TP
+.B prio-tc \fITC-MAP
+.TQ
+.B reco-prio-tc \fITC-MAP
+\fITC-MAP\fR uses the array parameter syntax, see dcb(8) for details. Keys are
+priorities, values are traffic classes. For each priority sets a TC where
+traffic with that priority is directed to.
+
+.TP
+.B tc-tsa \fITSA-MAP
+.TQ
+.B reco-tc-tsa \fITSA-MAP
+\fITC-MAP\fR uses the array parameter syntax, see dcb(8) for details. Keys are
+TCs, values are Transmission Selection Algorithm (TSA) keywords described below.
+For each TC sets an algorithm used for deciding how traffic queued up at this TC
+is scheduled for transmission. Supported TSAs are:
+
+.B strict
+- for strict priority, where traffic in higher-numbered TCs always takes
+precedence over traffic in lower-numbered TCs.
+.br
+.B ets
+- for Enhanced Traffic Selection, where available bandwidth is distributed among
+the ETS-enabled TCs according to the weights set by
+.B tc-bw
+and
+.B reco-tc-bw\fR,
+respectively.
+.br
+.B cbs
+- for Credit Based Shaper, where traffic is scheduled in a strict manner up to
+the limit set by a shaper.
+.br
+.B vendor
+- for vendor-specific traffic selection algorithm.
+
+.TP
+.B tc-bw \fIBW-MAP
+.TQ
+.B reco-tc-bw \fIBW-MAP
+\fIBW-MAP\fR uses the array parameter syntax, see dcb(8) for details. Keys are
+TCs, values are integers representing percent of available bandwidth given to
+the traffic class in question. The value should be 0 for TCs whose TSA is not
+\fBets\fR, and the sum of all values shall be 100. As an exception to the
+standard wording, a configuration with no ETS TCs is permitted to sum up to 0
+instead.
+.br
+
+.TP
+.B pg-bw \fIBW-MAP
+The precise meaning of \fBpg-bw\fR is not standardized, but the assumption seems
+to be that the same scheduling process as on the transmit side is applicable on
+receive side as well, and configures receive bandwidth allocation for \fBets\fR
+ingress traffic classes (priority groups).
+
+.SH EXAMPLE & USAGE
+
+Configure ETS priomap in a one-to-one fashion:
+
+.P
+# dcb ets set dev eth0 prio-tc 0:0 1:1 2:2 3:3 4:4 5:5 6:6 7:7
+
+Set TSA and transmit bandwidth configuration:
+
+.P
+# dcb ets set dev eth0 tc-tsa all:strict 0:ets 1:ets 2:ets \\
+.br
+                       tc-bw all:0 0:33 1:33 2:34
+
+Show what was set:
+
+.P
+# dcb ets show dev eth0 prio-tc tc-tsa tc-bw
+.br
+prio-tc 0:0 1:1 2:2 3:3 4:4 5:5 6:6 7:7
+.br
+tc-tsa 0:ets 1:ets 2:ets 3:strict 4:strict 5:strict 6:strict 7:strict
+.br
+tc-bw 0:33 1:33 2:34 3:0 4:0 5:0 6:0 7:0
+
+.SH EXIT STATUS
+Exit status is 0 if command was successful or a positive integer upon failure.
+
+.SH SEE ALSO
+.BR dcb (8)
+
+.SH REPORTING BUGS
+Report any bugs to the Network Developers mailing list
+.B <netdev@vger.kernel.org>
+where the development and maintenance is primarily done.
+You do not have to be subscribed to the list to send a message there.
+
+.SH AUTHOR
+Petr Machata <me@pmachata.org>
diff --git a/man/man8/dcb.8 b/man/man8/dcb.8
index 25ddf204d60e..ec116f6ce265 100644
--- a/man/man8/dcb.8
+++ b/man/man8/dcb.8
@@ -6,6 +6,13 @@ dcb \- show / manipulate DCB (Data Center Bridging) settings
 .ad l
 .in +8
 
+.ti -8
+.B dcb
+.RI "[ " OPTIONS " ] "
+.B ets
+.RI "{ " COMMAND " | " help " }"
+.sp
+
 .ti -8
 .B dcb
 .RB "[ " -force " ] "
@@ -46,6 +53,10 @@ When combined with -j generate a pretty JSON output.
 
 .SH OBJECTS
 
+.TP
+.B ets
+- Configuration of ETS (Enhanced Transmission Selection)
+
 .SH COMMANDS
 
 A \fICOMMAND\fR specifies the action to perform on the object. The set of
-- 
2.25.1

Re: [PATCH iproute2-next v2 00/11] Add a tool for configuration of DCB

[David Ahern]

On 10/30/20 6:29 AM, Petr Machata wrote:
> The Linux DCB interface allows configuration of a broad range of
> hardware-specific attributes, such as TC scheduling, flow control, per-port
> buffer configuration, TC rate, etc.
> 

...

> The patchset proceeds as follows:
> 
> - Many tools in iproute2 have an option to work in batch mode, where the
>   commands to run are given in a file. The code to handle batching is
>   largely the same independent of the tool in question. In patch #1, add a
>   helper to handle the batching, and migrate individual tools to use it.
> 
> - A number of configuration options come in a form of an on-off switch.
>   This in turn can be considered a special case of parsing one of a given
>   set of strings. In patch #2, extract helpers to parse one of a number of
>   strings, on top of which build an on-off parser.
> 
>   Currently each tool open-codes the logic to parse the on-off toggle. A
>   future patch set will migrate instances of this code over to the new
>   helpers.
> 
> - The on/off toggles from previous list item sometimes need to be dumped.
>   While in the FP output, one typically wishes to maintain consistency with
>   the command line and show actual strings, "on" and "off", in JSON output
>   one would rather use booleans. This logic is somewhat annoying to have to
>   open-code time and again. Therefore in patch #3, add a helper to do just
>   that.
> 
> - The DCB tool is built on top of libmnl. Several routines will be
>   basically the same in DCB as they are currently in devlink. In patches
>   #4-#6, extract them to a new module, mnl_utils, for easy reuse.
> 
> - Much of DCB is built around arrays. A syntax similar to the iplink_vlan's
>   ingress-qos-map / egress-qos-map is very handy for describing changes
>   done to such arrays. Therefore in patch #7, extract a helper,
>   parse_mapping(), which manages parsing of key-value arrays. In patch #8,
>   fix a buglet in the helper, and in patch #9, extend it to allow setting
>   of all array elements in one go.
> 
> - In patch #10, add a skeleton of "dcb", which contains common helpers and
>   dispatches to subtools for handling of individual objects. The skeleton
>   is empty as of this patch.
> 
>   In patch #11, add "dcb_ets", a module for handling of specifically DCB
>   ETS objects.
> 
>   The intention is to gradually add handlers for at least PFC, APP, peer
>   configuration, buffers and rates.
> 
> [1] https://github.com/Mellanox/mlnx-tools/tree/master/ofed_scripts
> 

overall this looks really good to me. Thanks for taking the time to do
the refactoring.