52   struct packet_ring *ring = &tunnel->ring;  in ring_create()  local
53   ring->numblocks          = TP_NUM_BLOCKS;  in ring_create()
55   int total_frames = TP_FRAMES * ring->numblocks;  in ring_create()
60     .tp_block_nr   = ring->numblocks,  // Number of blocks.  in ring_create()
69   size_t buflen = TP_BLOCK_SIZE * ring->numblocks;  in ring_create()
70   ring->base    = mmap(NULL, buflen, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_LOCKED | MAP_POPULATE,  in ring_create()
72   if (ring->base == MAP_FAILED) {  in ring_create()
77   ring->block    = 0;  in ring_create()
78   ring->slot     = 0;  in ring_create()
79   ring->numslots = TP_BLOCK_SIZE / TP_FRAME_SIZE;  in ring_create()
80   ring->next     = (struct tpacket2_hdr *)ring->base;  in ring_create()
83          buflen, ring->base);  in ring_create()
92 static struct tpacket2_hdr *ring_advance(struct packet_ring *ring) {  in ring_advance()  argument
93   uint8_t *next = (uint8_t *)ring->next;  in ring_advance()
95   ring->slot++;  in ring_advance()
98   if (ring->slot == ring->numslots) {  in ring_advance()
99     ring->slot = 0;  in ring_advance()
100     ring->block++;  in ring_advance()
102     if (ring->block < ring->numblocks) {  in ring_advance()
105       ring->block = 0;  in ring_advance()
106       next        = (uint8_t *)ring->base;  in ring_advance()
110   ring->next = (struct tpacket2_hdr *)next;  in ring_advance()
111   return ring->next;  in ring_advance()
120 void ring_read(struct packet_ring *ring, int write_fd, int to_ipv6) {  in ring_read()  argument
121   struct tpacket2_hdr *tp = ring->next;  in ring_read()
126     tp            = ring_advance(ring);  in ring_read()