#include <linux/debugfs.h>
#include <linux/err.h>
#include <linux/etherdevice.h>
#include <linux/inet.h>
#include <linux/kernel.h>
#include <linux/random.h>
#include <linux/slab.h>
#include <net/devlink.h>
#include <net/ip.h>
#include <net/psample.h>
#include <uapi/linux/ip.h>
#include <uapi/linux/udp.h>
#include "netdevsim.h"
#define NSIM_PSAMPLE_REPORT_INTERVAL_MS 100
#define NSIM_PSAMPLE_INVALID_TC 0xFFFF
#define NSIM_PSAMPLE_L4_DATA_LEN 100
struct nsim_dev_psample {
struct delayed_work psample_dw;
struct dentry *ddir;
struct psample_group *group;
u32 rate;
u32 group_num;
u32 trunc_size;
int in_ifindex;
int out_ifindex;
u16 out_tc;
u64 out_tc_occ_max;
u64 latency_max;
bool is_active;
};
static struct sk_buff *nsim_dev_psample_skb_build(void)
{
int tot_len, data_len = NSIM_PSAMPLE_L4_DATA_LEN;
struct sk_buff *skb;
struct udphdr *udph;
struct ethhdr *eth;
struct iphdr *iph;
skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
if (!skb)
return NULL;
tot_len = sizeof(struct iphdr) + sizeof(struct udphdr) + data_len;
skb_reset_mac_header(skb);
eth = skb_put(skb, sizeof(struct ethhdr));
eth_random_addr(eth->h_dest);
eth_random_addr(eth->h_source);
eth->h_proto = htons(ETH_P_IP);
skb->protocol = htons(ETH_P_IP);
skb_set_network_header(skb, skb->len);
iph = skb_put(skb, sizeof(struct iphdr));
iph->protocol = IPPROTO_UDP;
iph->saddr = in_aton("192.0.2.1");
iph->daddr = in_aton("198.51.100.1");
iph->version = 0x4;
iph->frag_off = 0;
iph->ihl = 0x5;
iph->tot_len = htons(tot_len);
iph->id = 0;
iph->ttl = 100;
iph->check = 0;
iph->check = ip_fast_csum((unsigned char *)iph, iph->ihl);
skb_set_transport_header(skb, skb->len);
udph = skb_put_zero(skb, sizeof(struct udphdr) + data_len);
get_random_bytes(&udph->source, sizeof(u16));
get_random_bytes(&udph->dest, sizeof(u16));
udph->len = htons(sizeof(struct udphdr) + data_len);
return skb;
}
static void nsim_dev_psample_md_prepare(const struct nsim_dev_psample *psample,
struct psample_metadata *md,
unsigned int len)
{
md->trunc_size = psample->trunc_size ? psample->trunc_size : len;
md->in_ifindex = psample->in_ifindex;
md->out_ifindex = psample->out_ifindex;
if (psample->out_tc != NSIM_PSAMPLE_INVALID_TC) {
md->out_tc = psample->out_tc;
md->out_tc_valid = 1;
}
if (psample->out_tc_occ_max) {
u64 out_tc_occ;
get_random_bytes(&out_tc_occ, sizeof(u64));
md->out_tc_occ = out_tc_occ & (psample->out_tc_occ_max - 1);
md->out_tc_occ_valid = 1;
}
if (psample->latency_max) {
u64 latency;
get_random_bytes(&latency, sizeof(u64));
md->latency = latency & (psample->latency_max - 1);
md->latency_valid = 1;
}
}
static void nsim_dev_psample_report_work(struct work_struct *work)
{
struct nsim_dev_psample *psample;
struct psample_metadata md = {};
struct sk_buff *skb;
unsigned long delay;
psample = container_of(work, struct nsim_dev_psample, psample_dw.work);
skb = nsim_dev_psample_skb_build();
if (!skb)
goto out;
nsim_dev_psample_md_prepare(psample, &md, skb->len);
psample_sample_packet(psample->group, skb, psample->rate, &md);
consume_skb(skb);
out:
delay = msecs_to_jiffies(NSIM_PSAMPLE_REPORT_INTERVAL_MS);
schedule_delayed_work(&psample->psample_dw, delay);
}
static int nsim_dev_psample_enable(struct nsim_dev *nsim_dev)
{
struct nsim_dev_psample *psample = nsim_dev->psample;
struct devlink *devlink;
unsigned long delay;
if (psample->is_active)
return -EBUSY;
devlink = priv_to_devlink(nsim_dev);
psample->group = psample_group_get(devlink_net(devlink),
psample->group_num);
if (!psample->group)
return -EINVAL;
delay = msecs_to_jiffies(NSIM_PSAMPLE_REPORT_INTERVAL_MS);
schedule_delayed_work(&psample->psample_dw, delay);
psample->is_active = true;
return 0;
}
static int nsim_dev_psample_disable(struct nsim_dev *nsim_dev)
{
struct nsim_dev_psample *psample = nsim_dev->psample;
if (!psample->is_active)
return -EINVAL;
psample->is_active = false;
cancel_delayed_work_sync(&psample->psample_dw);
psample_group_put(psample->group);
return 0;
}
static ssize_t nsim_dev_psample_enable_write(struct file *file,
const char __user *data,
size_t count, loff_t *ppos)
{
struct nsim_dev *nsim_dev = file->private_data;
bool enable;
int err;
err = kstrtobool_from_user(data, count, &enable);
if (err)
return err;
if (enable)
err = nsim_dev_psample_enable(nsim_dev);
else
err = nsim_dev_psample_disable(nsim_dev);
return err ? err : count;
}
static const struct file_operations nsim_psample_enable_fops = {
.open = simple_open,
.write = nsim_dev_psample_enable_write,
.llseek = generic_file_llseek,
.owner = THIS_MODULE,
};
int nsim_dev_psample_init(struct nsim_dev *nsim_dev)
{
struct nsim_dev_psample *psample;
int err;
psample = kzalloc_obj(*psample);
if (!psample)
return -ENOMEM;
nsim_dev->psample = psample;
INIT_DELAYED_WORK(&psample->psample_dw, nsim_dev_psample_report_work);
psample->ddir = debugfs_create_dir("psample", nsim_dev->ddir);
if (IS_ERR(psample->ddir)) {
err = PTR_ERR(psample->ddir);
goto err_psample_free;
}
psample->rate = 100;
debugfs_create_u32("rate", 0600, psample->ddir, &psample->rate);
psample->group_num = 10;
debugfs_create_u32("group_num", 0600, psample->ddir,
&psample->group_num);
psample->trunc_size = 0;
debugfs_create_u32("trunc_size", 0600, psample->ddir,
&psample->trunc_size);
psample->in_ifindex = 1;
debugfs_create_u32("in_ifindex", 0600, psample->ddir,
&psample->in_ifindex);
psample->out_ifindex = 2;
debugfs_create_u32("out_ifindex", 0600, psample->ddir,
&psample->out_ifindex);
psample->out_tc = 0;
debugfs_create_u16("out_tc", 0600, psample->ddir, &psample->out_tc);
psample->out_tc_occ_max = 10000;
debugfs_create_u64("out_tc_occ_max", 0600, psample->ddir,
&psample->out_tc_occ_max);
psample->latency_max = 50;
debugfs_create_u64("latency_max", 0600, psample->ddir,
&psample->latency_max);
debugfs_create_file("enable", 0200, psample->ddir, nsim_dev,
&nsim_psample_enable_fops);
return 0;
err_psample_free:
kfree(nsim_dev->psample);
return err;
}
void nsim_dev_psample_exit(struct nsim_dev *nsim_dev)
{
debugfs_remove_recursive(nsim_dev->psample->ddir);
if (nsim_dev->psample->is_active) {
cancel_delayed_work_sync(&nsim_dev->psample->psample_dw);
psample_group_put(nsim_dev->psample->group);
}
kfree(nsim_dev->psample);
}
