Fri, Jan 19, 2018 at 09:45:57PM CET, dsah...@gmail.com wrote:
>On 1/17/18 2:48 AM, Jiri Pirko wrote:
>> From: Jiri Pirko <j...@mellanox.com>
>>
>> This hepler used qdisc dump to list all qdisc and find if block index in
>> question is used by any of them. That means the block with specified
>> index exists.
>>
>> Signed-off-by: Jiri Pirko <j...@mellanox.com>
>> ---
>> tc/tc_qdisc.c | 61
>> +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
>> tc/tc_util.h | 2 ++
>> 2 files changed, 63 insertions(+)
>>
>> diff --git a/tc/tc_qdisc.c b/tc/tc_qdisc.c
>> index 70279b9..3f91558 100644
>> --- a/tc/tc_qdisc.c
>> +++ b/tc/tc_qdisc.c
>> @@ -412,3 +412,64 @@ int do_qdisc(int argc, char **argv)
>> fprintf(stderr, "Command \"%s\" is unknown, try \"tc qdisc help\".\n",
>> *argv);
>> return -1;
>> }
>> +
>> +struct tc_qdisc_block_exists_ctx {
>> + __u32 block_index;
>> + bool found;
>> +};
>> +
>> +static int tc_qdisc_block_exists_cb(const struct sockaddr_nl *who,
>> + struct nlmsghdr *n, void *arg)
>> +{
>> + struct tc_qdisc_block_exists_ctx *ctx = arg;
>> + struct tcmsg *t = NLMSG_DATA(n);
>> + int len = n->nlmsg_len;
>> + struct rtattr *tb[TCA_MAX+1];
>
>reverse xmas tree
:) Will fix
>
>> +
>> + if (n->nlmsg_type != RTM_NEWQDISC)
>> + return 0;
>> +
>> + len -= NLMSG_LENGTH(sizeof(*t));
>> + if (len < 0)
>> + return -1;
>> +
>> + parse_rtattr(tb, TCA_MAX, TCA_RTA(t), len);
>> +
>> + if (tb[TCA_KIND] == NULL)
>> + return -1;
>> +
>> + if (tb[TCA_INGRESS_BLOCK] &&
>> + RTA_PAYLOAD(tb[TCA_INGRESS_BLOCK]) >= sizeof(__u32)) {
>
>why not just == sizeof(__u32) since that's what it should be?
test1:~/iproute2$ git grep "== sizeof(__u32)" | grep RTA_PAYLOAD| wc -l
1
test1:~/iproute2$ git grep ">= sizeof(__u32)" | grep RTA_PAYLOAD| wc -l
42
I just go with the flow :)
>
>> + __u32 block = rta_getattr_u32(tb[TCA_INGRESS_BLOCK]);
>> +
>> + if (block && block == ctx->block_index)
>
>block > 0 test should not be needed. If someone is calling
>tc_qdisc_block_exists, then block_index should be > 0 in which case you
>just need block == ctx->block_index
Right. Will Fix.
>
>
>> + ctx->found = true;
>> + }
>> +
>> + if (tb[TCA_EGRESS_BLOCK] &&
>> + RTA_PAYLOAD(tb[TCA_EGRESS_BLOCK]) >= sizeof(__u32)) {
>> + __u32 block = rta_getattr_u32(tb[TCA_EGRESS_BLOCK]);
>> +
>> + if (block && block == ctx->block_index)
>
>same 2 comments for this block
ack
>
>> + ctx->found = true;
>> + }
>> + return 0;
>> +}
>> +
>> +int tc_qdisc_block_exists(__u32 block_index)
>
>This should be bool since you are returning true / false
Ah, missed that. Fixing.
>
>> +{
>> + struct tc_qdisc_block_exists_ctx ctx = { .block_index = block_index };
>> + struct tcmsg t = { .tcm_family = AF_UNSPEC };
>> +
>> + if (rtnl_dump_request(&rth, RTM_GETQDISC, &t, sizeof(t)) < 0) {
>> + perror("Cannot send dump request");
>> + return false;
>> + }
>> +
>> + if (rtnl_dump_filter(&rth, tc_qdisc_block_exists_cb, &ctx) < 0) {
>> + perror("Dump terminated\n");
>> + return false;
>> + }
>> +
>> + return ctx.found;
>> +}
>> diff --git a/tc/tc_util.h b/tc/tc_util.h
>> index 1218610..72f4282 100644
>> --- a/tc/tc_util.h
>> +++ b/tc/tc_util.h
>> @@ -132,4 +132,6 @@ int prio_print_opt(struct qdisc_util *qu, FILE *f,
>> struct rtattr *opt);
>> int cls_names_init(char *path);
>> void cls_names_uninit(void);
>>
>> +int tc_qdisc_block_exists(__u32 block_index);
>> +
>> #endif
>>
>
