[PATCH 2/2] iproute2: add support for invisible qdisc dumping

From: Jiri Kosina <redacted>

Support the new TCA_DUMP_INVISIBLE netlink attribute that allows asking 
kernel to perform 'full qdisc dump', as for historical reasons some of the 
default qdiscs are being hidden by the kernel.

The command syntax is being extended by voluntary 'invisible' argument to
'tc qdisc show'.

Signed-off-by: Jiri Kosina <redacted>
---
 tc/tc_qdisc.c | 25 +++++++++++++++++++++++--
 1 file changed, 23 insertions(+), 2 deletions(-)

diff --git a/tc/tc_qdisc.c b/tc/tc_qdisc.c
index 3a3701c2..29da9269 100644
--- a/tc/tc_qdisc.c
+++ b/tc/tc_qdisc.c

@@ -34,7 +34,7 @@ static int usage(void)
 	fprintf(stderr, "       [ stab [ help | STAB_OPTIONS] ]\n");
 	fprintf(stderr, "       [ [ QDISC_KIND ] [ help | OPTIONS ] ]\n");
 	fprintf(stderr, "\n");
-	fprintf(stderr, "       tc qdisc show [ dev STRING ] [ ingress | clsact ]\n");
+	fprintf(stderr, "       tc qdisc show [ dev STRING ] [ ingress | clsact | invisible ]\n");
 	fprintf(stderr, "Where:\n");
 	fprintf(stderr, "QDISC_KIND := { [p|b]fifo | tbf | prio | cbq | red | etc. }\n");
 	fprintf(stderr, "OPTIONS := ... try tc qdisc add <desired QDISC_KIND> help\n");

@@ -292,6 +292,7 @@ static int tc_qdisc_list(int argc, char **argv)
 {
 	struct tcmsg t = { .tcm_family = AF_UNSPEC };
 	char d[16] = {};
+	bool dump_invisible = false;
 
 	while (argc > 0) {
 		if (strcmp(*argv, "dev") == 0) {

@@ -306,6 +307,8 @@ static int tc_qdisc_list(int argc, char **argv)
 			t.tcm_parent = TC_H_INGRESS;
 		} else if (matches(*argv, "help") == 0) {
 			usage();
+		} else if (strcmp(*argv, "invisible") == 0) {
+			dump_invisible = true;
 		} else {
 			fprintf(stderr, "What is \"%s\"? Try \"tc qdisc help\".\n", *argv);
 			return -1;

@@ -325,7 +328,25 @@ static int tc_qdisc_list(int argc, char **argv)
 		filter_ifindex = t.tcm_ifindex;
 	}
 
-	if (rtnl_dump_request(&rth, RTM_GETQDISC, &t, sizeof(t)) < 0) {
+	if (dump_invisible) {
+		struct {
+			struct nlmsghdr n;
+			struct tcmsg t;
+			char buf[256];
+		} req = {
+			.n.nlmsg_type = RTM_GETQDISC,
+			.n.nlmsg_len = NLMSG_LENGTH(sizeof(struct tcmsg)),
+		};
+
+		req.t.tcm_family = AF_UNSPEC;
+
+		addattr(&req.n, 256, TCA_DUMP_INVISIBLE);
+		if (rtnl_dump_request_n(&rth, &req.n) < 0) {
+			perror("Cannot send dump request");
+			return 1;
+		}
+
+	} else if (rtnl_dump_request(&rth, RTM_GETQDISC, &t, sizeof(t)) < 0) {
 		perror("Cannot send dump request");
 		return 1;
 	}

-- 
Jiri Kosina
SUSE Labs

On Sat, Feb 25, 2017 at 10:29:17PM +0100, Jiri Kosina wrote:

From: Jiri Kosina <redacted>

Support the new TCA_DUMP_INVISIBLE netlink attribute that allows asking 
kernel to perform 'full qdisc dump', as for historical reasons some of the 
default qdiscs are being hidden by the kernel.

The command syntax is being extended by voluntary 'invisible' argument to
'tc qdisc show'.

Signed-off-by: Jiri Kosina <redacted>
---
 tc/tc_qdisc.c | 25 +++++++++++++++++++++++--
 1 file changed, 23 insertions(+), 2 deletions(-)

Would you mind adding a description of the new keyword to tc man page as
well?

Doesn't look like these are mutually exclusive. Therefore I would
suggest fixing the syntax to:

| +	fprintf(stderr, "       tc qdisc show [ dev STRING ] [ ingress | clsact ] [ invisible ]\n");

Cheers, Phil

On Sat, 25 Feb 2017 22:29:17 +0100 (CET)
Jiri Kosina [off-list ref] wrote:

From: Jiri Kosina <redacted>

Support the new TCA_DUMP_INVISIBLE netlink attribute that allows asking 
kernel to perform 'full qdisc dump', as for historical reasons some of the 
default qdiscs are being hidden by the kernel.

The command syntax is being extended by voluntary 'invisible' argument to
'tc qdisc show'.

Signed-off-by: Jiri Kosina <redacted>

Still waiting for TCA_DUMP_INVISIBLE to make it into net-next

On Mon, 27 Feb 2017, Phil Sutter wrote:

quoted

Support the new TCA_DUMP_INVISIBLE netlink attribute that allows asking 
kernel to perform 'full qdisc dump', as for historical reasons some of the 
default qdiscs are being hidden by the kernel.

The command syntax is being extended by voluntary 'invisible' argument to
'tc qdisc show'.

Signed-off-by: Jiri Kosina <redacted>
---
 tc/tc_qdisc.c | 25 +++++++++++++++++++++++--
 1 file changed, 23 insertions(+), 2 deletions(-)

Would you mind adding a description of the new keyword to tc man page as
well?

Seems like tc manpage would need more updates, as it doesn't seem to 
reflect the '[ ingress | clsact ]' possibility either. So I'll send this 
as a followup patch, fixing all these at once.

quoted

diff --git a/tc/tc_qdisc.c b/tc/tc_qdisc.c
index 3a3701c2..29da9269 100644
--- a/tc/tc_qdisc.c
+++ b/tc/tc_qdisc.c

@@ -34,7 +34,7 @@ static int usage(void)
 	fprintf(stderr, "       [ stab [ help | STAB_OPTIONS] ]\n");
 	fprintf(stderr, "       [ [ QDISC_KIND ] [ help | OPTIONS ] ]\n");
 	fprintf(stderr, "\n");
-	fprintf(stderr, "       tc qdisc show [ dev STRING ] [ ingress | clsact ]\n");
+	fprintf(stderr, "       tc qdisc show [ dev STRING ] [ ingress | clsact | invisible ]\n");

Doesn't look like these are mutually exclusive. Therefore I would
suggest fixing the syntax to:

| +	fprintf(stderr, "       tc qdisc show [ dev STRING ] [ ingress | clsact ] [ invisible ]\n");

Makes sense, will include this in v2.

Thanks,

-- 
Jiri Kosina
SUSE Labs