2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
4 * Copyright (C) 2011-2016 Universita` di Pisa
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
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15 * documentation and/or other materials provided with the distribution.
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
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20 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
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24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33 * Functions and macros to manipulate netmap structures and packets
34 * in userspace. See netmap(4) for more information.
36 * The address of the struct netmap_if, say nifp, is computed from the
37 * value returned from ioctl(.., NIOCREG, ...) and the mmap region:
38 * ioctl(fd, NIOCREG, &req);
39 * mem = mmap(0, ... );
40 * nifp = NETMAP_IF(mem, req.nr_nifp);
41 * (so simple, we could just do it manually)
44 * struct netmap_ring *NETMAP_TXRING(nifp, index)
45 * struct netmap_ring *NETMAP_RXRING(nifp, index)
46 * we can access ring->cur, ring->head, ring->tail, etc.
48 * ring->slot[i] gives us the i-th slot (we can access
49 * directly len, flags, buf_idx)
51 * char *buf = NETMAP_BUF(ring, x) returns a pointer to
52 * the buffer numbered x
54 * All ring indexes (head, cur, tail) should always move forward.
55 * To compute the next index in a circular ring you can use
56 * i = nm_ring_next(ring, i);
58 * To ease porting apps from pcap to netmap we supply a few fuctions
59 * that can be called to open, close, read and write on netmap in a way
60 * similar to libpcap. Note that the read/write function depend on
61 * an ioctl()/select()/poll() being issued to refill rings or push
64 * In order to use these, include #define NETMAP_WITH_LIBS
65 * in the source file that invokes these functions.
68 #ifndef _NET_NETMAP_USER_H_
69 #define _NET_NETMAP_USER_H_
71 #define NETMAP_DEVICE_NAME "/dev/netmap"
75 * we can compile userspace apps with either cygwin or msvc,
76 * and we use _WIN32 to identify windows specific code
82 #endif /* __CYGWIN__ */
85 #undef NETMAP_DEVICE_NAME
86 #define NETMAP_DEVICE_NAME "/proc/sys/DosDevices/Global/netmap"
89 #include <sys/cygwin.h>
93 #include <sys/socket.h> /* apple needs sockaddr */
94 #include <net/if.h> /* IFNAMSIZ */
98 #define likely(x) __builtin_expect(!!(x), 1)
99 #define unlikely(x) __builtin_expect(!!(x), 0)
100 #endif /* likely and unlikely */
102 #include <net/netmap.h>
105 #define _NETMAP_OFFSET(type, ptr, offset) \
106 ((type)(void *)((char *)(ptr) + (offset)))
108 #define NETMAP_IF(_base, _ofs) _NETMAP_OFFSET(struct netmap_if *, _base, _ofs)
110 #define NETMAP_TXRING(nifp, index) _NETMAP_OFFSET(struct netmap_ring *, \
111 nifp, (nifp)->ring_ofs[index] )
113 #define NETMAP_RXRING(nifp, index) _NETMAP_OFFSET(struct netmap_ring *, \
114 nifp, (nifp)->ring_ofs[index + (nifp)->ni_tx_rings + 1] )
116 #define NETMAP_BUF(ring, index) \
117 ((char *)(ring) + (ring)->buf_ofs + ((index)*(ring)->nr_buf_size))
119 #define NETMAP_BUF_IDX(ring, buf) \
120 ( ((char *)(buf) - ((char *)(ring) + (ring)->buf_ofs) ) / \
121 (ring)->nr_buf_size )
124 static inline uint32_t
125 nm_ring_next(struct netmap_ring *r, uint32_t i)
127 return ( unlikely(i + 1 == r->num_slots) ? 0 : i + 1);
132 * Return 1 if we have pending transmissions in the tx ring.
133 * When everything is complete ring->head = ring->tail + 1 (modulo ring size)
136 nm_tx_pending(struct netmap_ring *r)
138 return nm_ring_next(r, r->tail) != r->head;
142 static inline uint32_t
143 nm_ring_space(struct netmap_ring *ring)
145 int ret = ring->tail - ring->cur;
147 ret += ring->num_slots;
152 #ifdef NETMAP_WITH_LIBS
154 * Support for simple I/O libraries.
155 * Include other system headers required for compiling this.
158 #ifndef HAVE_NETMAP_WITH_LIBS
159 #define HAVE_NETMAP_WITH_LIBS
162 #include <sys/time.h>
163 #include <sys/mman.h>
164 #include <string.h> /* memset */
165 #include <sys/ioctl.h>
166 #include <sys/errno.h> /* EINVAL */
167 #include <fcntl.h> /* O_RDWR */
168 #include <unistd.h> /* close() */
172 #ifndef ND /* debug macros */
174 #define ND(_fmt, ...) do {} while(0)
175 #define D(_fmt, ...) \
177 struct timeval _t0; \
178 gettimeofday(&_t0, NULL); \
179 fprintf(stderr, "%03d.%06d %s [%d] " _fmt "\n", \
180 (int)(_t0.tv_sec % 1000), (int)_t0.tv_usec, \
181 __FUNCTION__, __LINE__, ##__VA_ARGS__); \
184 /* Rate limited version of "D", lps indicates how many per second */
185 #define RD(lps, format, ...) \
187 static int __t0, __cnt; \
188 struct timeval __xxts; \
189 gettimeofday(&__xxts, NULL); \
190 if (__t0 != __xxts.tv_sec) { \
191 __t0 = __xxts.tv_sec; \
194 if (__cnt++ < lps) { \
195 D(format, ##__VA_ARGS__); \
200 struct nm_pkthdr { /* first part is the same as pcap_pkthdr */
205 uint64_t flags; /* NM_MORE_PKTS etc */
206 #define NM_MORE_PKTS 1
208 struct netmap_slot *slot;
212 struct nm_stat { /* same as pcap_stat */
216 #ifdef WIN32 /* XXX or _WIN32 ? */
221 #define NM_ERRBUF_SIZE 512
224 struct nm_desc *self; /* point to self if netmap. */
228 int done_mmap; /* set if mem is the result of mmap */
229 struct netmap_if * const nifp;
230 uint16_t first_tx_ring, last_tx_ring, cur_tx_ring;
231 uint16_t first_rx_ring, last_rx_ring, cur_rx_ring;
232 struct nmreq req; /* also contains the nr_name = ifname */
233 struct nm_pkthdr hdr;
236 * The memory contains netmap_if, rings and then buffers.
237 * Given a pointer (e.g. to nm_inject) we can compare with
238 * mem/buf_start/buf_end to tell if it is a buffer or
239 * some other descriptor in our region.
240 * We also store a pointer to some ring as it helps in the
241 * translation from buffer indexes to addresses.
243 struct netmap_ring * const some_ring;
244 void * const buf_start;
245 void * const buf_end;
246 /* parameters from pcap_open_live */
252 /* save flags so we can restore them on close */
258 char msg[NM_ERRBUF_SIZE];
262 * when the descriptor is open correctly, d->self == d
263 * Eventually we should also use some magic number.
265 #define P2NMD(p) ((struct nm_desc *)(p))
266 #define IS_NETMAP_DESC(d) ((d) && P2NMD(d)->self == P2NMD(d))
267 #define NETMAP_FD(d) (P2NMD(d)->fd)
271 * this is a slightly optimized copy routine which rounds
272 * to multiple of 64 bytes and is often faster than dealing
273 * with other odd sizes. We assume there is enough room
274 * in the source and destination buffers.
277 nm_pkt_copy(const void *_src, void *_dst, int l)
279 const uint64_t *src = (const uint64_t *)_src;
280 uint64_t *dst = (uint64_t *)_dst;
282 if (unlikely(l >= 1024 || l % 64)) {
286 for (; likely(l > 0); l-=64) {
300 * The callback, invoked on each received packet. Same as libpcap
302 typedef void (*nm_cb_t)(u_char *, const struct nm_pkthdr *, const u_char *d);
305 *--- the pcap-like API ---
307 * nm_open() opens a file descriptor, binds to a port and maps memory.
309 * ifname (netmap:foo or vale:foo) is the port name
310 * a suffix can indicate the follwing:
311 * ^ bind the host (sw) ring pair
312 * * bind host and NIC ring pairs
313 * -NN bind individual NIC ring pair
314 * {NN bind master side of pipe NN
315 * }NN bind slave side of pipe NN
316 * a suffix starting with / and the following flags,
319 * z zero copy monitor (both tx and rx)
320 * t monitor tx side (copy monitor)
321 * r monitor rx side (copy monitor)
322 * R bind only RX ring(s)
323 * T bind only TX ring(s)
325 * req provides the initial values of nmreq before parsing ifname.
326 * Remember that the ifname parsing will override the ring
327 * number in nm_ringid, and part of nm_flags;
328 * flags special functions, normally 0
329 * indicates which fields of *arg are significant
330 * arg special functions, normally NULL
331 * if passed a netmap_desc with mem != NULL,
332 * use that memory instead of mmap.
335 static struct nm_desc *nm_open(const char *ifname, const struct nmreq *req,
336 uint64_t flags, const struct nm_desc *arg);
339 * nm_open can import some fields from the parent descriptor.
340 * These flags control which ones.
341 * Also in flags you can specify NETMAP_NO_TX_POLL and NETMAP_DO_RX_POLL,
342 * which set the initial value for these flags.
343 * Note that the 16 low bits of the flags are reserved for data
344 * that may go into the nmreq.
347 NM_OPEN_NO_MMAP = 0x040000, /* reuse mmap from parent */
348 NM_OPEN_IFNAME = 0x080000, /* nr_name, nr_ringid, nr_flags */
349 NM_OPEN_ARG1 = 0x100000,
350 NM_OPEN_ARG2 = 0x200000,
351 NM_OPEN_ARG3 = 0x400000,
352 NM_OPEN_RING_CFG = 0x800000, /* tx|rx rings|slots */
357 * nm_close() closes and restores the port to its previous state
360 static int nm_close(struct nm_desc *);
363 * nm_mmap() do mmap or inherit from parent if the nr_arg2
364 * (memory block) matches.
367 static int nm_mmap(struct nm_desc *, const struct nm_desc *);
370 * nm_inject() is the same as pcap_inject()
371 * nm_dispatch() is the same as pcap_dispatch()
372 * nm_nextpkt() is the same as pcap_next()
375 static int nm_inject(struct nm_desc *, const void *, size_t);
376 static int nm_dispatch(struct nm_desc *, int, nm_cb_t, u_char *);
377 static u_char *nm_nextpkt(struct nm_desc *, struct nm_pkthdr *);
381 intptr_t _get_osfhandle(int); /* defined in io.h in windows */
384 * In windows we do not have yet native poll support, so we keep track
385 * of file descriptors associated to netmap ports to emulate poll on
386 * them and fall back on regular poll on other file descriptors.
388 struct win_netmap_fd_list {
389 struct win_netmap_fd_list *next;
391 HANDLE win_netmap_handle;
395 * list head containing all the netmap opened fd and their
396 * windows HANDLE counterparts
398 static struct win_netmap_fd_list *win_netmap_fd_list_head;
401 win_insert_fd_record(int fd)
403 struct win_netmap_fd_list *curr;
405 for (curr = win_netmap_fd_list_head; curr; curr = curr->next) {
406 if (fd == curr->win_netmap_fd) {
410 curr = calloc(1, sizeof(*curr));
411 curr->next = win_netmap_fd_list_head;
412 curr->win_netmap_fd = fd;
413 curr->win_netmap_handle = IntToPtr(_get_osfhandle(fd));
414 win_netmap_fd_list_head = curr;
418 win_remove_fd_record(int fd)
420 struct win_netmap_fd_list *curr = win_netmap_fd_list_head;
421 struct win_netmap_fd_list *prev = NULL;
422 for (; curr ; prev = curr, curr = curr->next) {
423 if (fd != curr->win_netmap_fd)
425 /* found the entry */
426 if (prev == NULL) { /* we are freeing the first entry */
427 win_netmap_fd_list_head = curr->next;
429 prev->next = curr->next;
438 win_get_netmap_handle(int fd)
440 struct win_netmap_fd_list *curr;
442 for (curr = win_netmap_fd_list_head; curr; curr = curr->next) {
443 if (fd == curr->win_netmap_fd) {
444 return curr->win_netmap_handle;
451 * we need to wrap ioctl and mmap, at least for the netmap file descriptors
455 * use this function only from netmap_user.h internal functions
456 * same as ioctl, returns 0 on success and -1 on error
459 win_nm_ioctl_internal(HANDLE h, int32_t ctlCode, void *arg)
461 DWORD bReturn = 0, szIn, szOut;
462 BOOL ioctlReturnStatus;
463 void *inParam = arg, *outParam = arg;
467 szIn = sizeof(POLL_REQUEST_DATA);
468 szOut = sizeof(POLL_REQUEST_DATA);
472 szOut = sizeof(void*);
473 inParam = NULL; /* nothing on input */
481 szIn = sizeof(struct nmreq);
482 szOut = sizeof(struct nmreq);
485 D("unsupported NIOCCONFIG!");
488 default: /* a regular ioctl */
489 D("invalid ioctl %x on netmap fd", ctlCode);
493 ioctlReturnStatus = DeviceIoControl(h,
494 ctlCode, inParam, szIn,
497 // XXX note windows returns 0 on error or async call, 1 on success
498 // we could call GetLastError() to figure out what happened
499 return ioctlReturnStatus ? 0 : -1;
503 * this function is what must be called from user-space programs
504 * same as ioctl, returns 0 on success and -1 on error
507 win_nm_ioctl(int fd, int32_t ctlCode, void *arg)
509 HANDLE h = win_get_netmap_handle(fd);
512 return ioctl(fd, ctlCode, arg);
514 return win_nm_ioctl_internal(h, ctlCode, arg);
518 #define ioctl win_nm_ioctl /* from now on, within this file ... */
521 * We cannot use the native mmap on windows
522 * The only parameter used is "fd", the other ones are just declared to
523 * make this signature comparable to the FreeBSD/Linux one
526 win32_mmap_emulated(void *addr, size_t length, int prot, int flags, int fd, int32_t offset)
528 HANDLE h = win_get_netmap_handle(fd);
531 return mmap(addr, length, prot, flags, fd, offset);
535 return win_nm_ioctl_internal(h, NETMAP_MMAP, &ret) ?
536 NULL : ret.pUsermodeVirtualAddress;
540 #define mmap win32_mmap_emulated
542 #include <sys/poll.h> /* XXX needed to use the structure pollfd */
545 win_nm_poll(struct pollfd *fds, int nfds, int timeout)
549 if (nfds != 1 || fds == NULL || (h = win_get_netmap_handle(fds->fd)) == NULL) {;
550 return poll(fds, nfds, timeout);
552 POLL_REQUEST_DATA prd;
554 prd.timeout = timeout;
555 prd.events = fds->events;
557 win_nm_ioctl_internal(h, NETMAP_POLL, &prd);
558 if ((prd.revents == POLLERR) || (prd.revents == STATUS_TIMEOUT)) {
565 #define poll win_nm_poll
568 win_nm_open(char* pathname, int flags)
571 if (strcmp(pathname, NETMAP_DEVICE_NAME) == 0) {
572 int fd = open(NETMAP_DEVICE_NAME, O_RDWR);
577 win_insert_fd_record(fd);
580 return open(pathname, flags);
584 #define open win_nm_open
591 if (win_get_netmap_handle(fd) != NULL) {
592 win_remove_fd_record(fd);
598 #define close win_nm_close
603 nm_is_identifier(const char *s, const char *e)
605 for (; s != e; s++) {
606 if (!isalnum(*s) && *s != '_') {
616 nm_parse(const char *ifname, struct nm_desc *d, char *err)
619 const char *port = NULL;
620 const char *vpname = NULL;
622 uint32_t nr_ringid = 0, nr_flags;
623 char errmsg[MAXERRMSG] = "";
625 uint16_t nr_arg2 = 0;
626 enum { P_START, P_RNGSFXOK, P_GETNUM, P_FLAGS, P_FLAGSOK, P_MEMID } p_state;
630 is_vale = (ifname[0] == 'v');
632 port = index(ifname, ':');
634 snprintf(errmsg, MAXERRMSG,
635 "missing ':' in vale name");
639 if (!nm_is_identifier(ifname + 4, port)) {
640 snprintf(errmsg, MAXERRMSG, "invalid bridge name");
650 /* scan for a separator */
651 for (; *port && !index("-*^{}/@", *port); port++)
654 if (is_vale && !nm_is_identifier(vpname, port)) {
655 snprintf(errmsg, MAXERRMSG, "invalid bridge port name");
659 namelen = port - ifname;
660 if (namelen >= sizeof(d->req.nr_name)) {
661 snprintf(errmsg, MAXERRMSG, "name too long");
664 memcpy(d->req.nr_name, ifname, namelen);
665 d->req.nr_name[namelen] = '\0';
668 nr_flags = NR_REG_ALL_NIC; /* default for no suffix */
673 case '^': /* only SW ring */
674 nr_flags = NR_REG_SW;
675 p_state = P_RNGSFXOK;
677 case '*': /* NIC and SW */
678 nr_flags = NR_REG_NIC_SW;
679 p_state = P_RNGSFXOK;
681 case '-': /* one NIC ring pair */
682 nr_flags = NR_REG_ONE_NIC;
685 case '{': /* pipe (master endpoint) */
686 nr_flags = NR_REG_PIPE_MASTER;
689 case '}': /* pipe (slave endoint) */
690 nr_flags = NR_REG_PIPE_SLAVE;
693 case '/': /* start of flags */
696 case '@': /* start of memid */
700 snprintf(errmsg, MAXERRMSG, "unknown modifier: '%c'", *port);
714 snprintf(errmsg, MAXERRMSG, "unexpected character: '%c'", *port);
720 num = strtol(port, (char **)&port, 10);
721 if (num < 0 || num >= NETMAP_RING_MASK) {
722 snprintf(errmsg, MAXERRMSG, "'%ld' out of range [0, %d)",
723 num, NETMAP_RING_MASK);
726 nr_ringid = num & NETMAP_RING_MASK;
727 p_state = P_RNGSFXOK;
738 nr_flags |= NR_EXCLUSIVE;
741 nr_flags |= NR_ZCOPY_MON;
744 nr_flags |= NR_MONITOR_TX;
747 nr_flags |= NR_MONITOR_RX;
750 nr_flags |= NR_RX_RINGS_ONLY;
753 nr_flags |= NR_TX_RINGS_ONLY;
756 snprintf(errmsg, MAXERRMSG, "unrecognized flag: '%c'", *port);
764 snprintf(errmsg, MAXERRMSG, "double setting of memid");
767 num = strtol(port, (char **)&port, 10);
769 snprintf(errmsg, MAXERRMSG, "invalid memid %ld, must be >0", num);
773 p_state = P_RNGSFXOK;
777 if (p_state != P_START && p_state != P_RNGSFXOK && p_state != P_FLAGSOK) {
778 snprintf(errmsg, MAXERRMSG, "unexpected end of port name");
781 ND("flags: %s %s %s %s",
782 (nr_flags & NR_EXCLUSIVE) ? "EXCLUSIVE" : "",
783 (nr_flags & NR_ZCOPY_MON) ? "ZCOPY_MON" : "",
784 (nr_flags & NR_MONITOR_TX) ? "MONITOR_TX" : "",
785 (nr_flags & NR_MONITOR_RX) ? "MONITOR_RX" : "");
787 d->req.nr_flags |= nr_flags;
788 d->req.nr_ringid |= nr_ringid;
789 d->req.nr_arg2 = nr_arg2;
798 strncpy(err, errmsg, MAXERRMSG);
803 * Try to open, return descriptor if successful, NULL otherwise.
804 * An invalid netmap name will return errno = 0;
805 * You can pass a pointer to a pre-filled nm_desc to add special
806 * parameters. Flags is used as follows
807 * NM_OPEN_NO_MMAP use the memory from arg, only XXX avoid mmap
808 * if the nr_arg2 (memory block) matches.
809 * NM_OPEN_ARG1 use req.nr_arg1 from arg
810 * NM_OPEN_ARG2 use req.nr_arg2 from arg
811 * NM_OPEN_RING_CFG user ring config from arg
813 static struct nm_desc *
814 nm_open(const char *ifname, const struct nmreq *req,
815 uint64_t new_flags, const struct nm_desc *arg)
817 struct nm_desc *d = NULL;
818 const struct nm_desc *parent = arg;
819 char errmsg[MAXERRMSG] = "";
822 if (strncmp(ifname, "netmap:", 7) &&
823 strncmp(ifname, NM_BDG_NAME, strlen(NM_BDG_NAME))) {
824 errno = 0; /* name not recognised, not an error */
828 d = (struct nm_desc *)calloc(1, sizeof(*d));
830 snprintf(errmsg, MAXERRMSG, "nm_desc alloc failure");
834 d->self = d; /* set this early so nm_close() works */
835 d->fd = open(NETMAP_DEVICE_NAME, O_RDWR);
837 snprintf(errmsg, MAXERRMSG, "cannot open /dev/netmap: %s", strerror(errno));
844 if (!(new_flags & NM_OPEN_IFNAME)) {
845 if (nm_parse(ifname, d, errmsg) < 0)
849 d->req.nr_version = NETMAP_API;
850 d->req.nr_ringid &= NETMAP_RING_MASK;
852 /* optionally import info from parent */
853 if (IS_NETMAP_DESC(parent) && new_flags) {
854 if (new_flags & NM_OPEN_ARG1)
855 D("overriding ARG1 %d", parent->req.nr_arg1);
856 d->req.nr_arg1 = new_flags & NM_OPEN_ARG1 ?
857 parent->req.nr_arg1 : 4;
858 if (new_flags & NM_OPEN_ARG2) {
859 D("overriding ARG2 %d", parent->req.nr_arg2);
860 d->req.nr_arg2 = parent->req.nr_arg2;
862 if (new_flags & NM_OPEN_ARG3)
863 D("overriding ARG3 %d", parent->req.nr_arg3);
864 d->req.nr_arg3 = new_flags & NM_OPEN_ARG3 ?
865 parent->req.nr_arg3 : 0;
866 if (new_flags & NM_OPEN_RING_CFG) {
867 D("overriding RING_CFG");
868 d->req.nr_tx_slots = parent->req.nr_tx_slots;
869 d->req.nr_rx_slots = parent->req.nr_rx_slots;
870 d->req.nr_tx_rings = parent->req.nr_tx_rings;
871 d->req.nr_rx_rings = parent->req.nr_rx_rings;
873 if (new_flags & NM_OPEN_IFNAME) {
874 D("overriding ifname %s ringid 0x%x flags 0x%x",
875 parent->req.nr_name, parent->req.nr_ringid,
876 parent->req.nr_flags);
877 memcpy(d->req.nr_name, parent->req.nr_name,
878 sizeof(d->req.nr_name));
879 d->req.nr_ringid = parent->req.nr_ringid;
880 d->req.nr_flags = parent->req.nr_flags;
883 /* add the *XPOLL flags */
884 d->req.nr_ringid |= new_flags & (NETMAP_NO_TX_POLL | NETMAP_DO_RX_POLL);
886 if (ioctl(d->fd, NIOCREGIF, &d->req)) {
887 snprintf(errmsg, MAXERRMSG, "NIOCREGIF failed: %s", strerror(errno));
891 nr_reg = d->req.nr_flags & NR_REG_MASK;
893 if (nr_reg == NR_REG_SW) { /* host stack */
894 d->first_tx_ring = d->last_tx_ring = d->req.nr_tx_rings;
895 d->first_rx_ring = d->last_rx_ring = d->req.nr_rx_rings;
896 } else if (nr_reg == NR_REG_ALL_NIC) { /* only nic */
897 d->first_tx_ring = 0;
898 d->first_rx_ring = 0;
899 d->last_tx_ring = d->req.nr_tx_rings - 1;
900 d->last_rx_ring = d->req.nr_rx_rings - 1;
901 } else if (nr_reg == NR_REG_NIC_SW) {
902 d->first_tx_ring = 0;
903 d->first_rx_ring = 0;
904 d->last_tx_ring = d->req.nr_tx_rings;
905 d->last_rx_ring = d->req.nr_rx_rings;
906 } else if (nr_reg == NR_REG_ONE_NIC) {
907 /* XXX check validity */
908 d->first_tx_ring = d->last_tx_ring =
909 d->first_rx_ring = d->last_rx_ring = d->req.nr_ringid & NETMAP_RING_MASK;
911 d->first_tx_ring = d->last_tx_ring = 0;
912 d->first_rx_ring = d->last_rx_ring = 0;
915 /* if parent is defined, do nm_mmap() even if NM_OPEN_NO_MMAP is set */
916 if ((!(new_flags & NM_OPEN_NO_MMAP) || parent) && nm_mmap(d, parent)) {
917 snprintf(errmsg, MAXERRMSG, "mmap failed: %s", strerror(errno));
922 #ifdef DEBUG_NETMAP_USER
923 { /* debugging code */
926 D("%s tx %d .. %d %d rx %d .. %d %d", ifname,
927 d->first_tx_ring, d->last_tx_ring, d->req.nr_tx_rings,
928 d->first_rx_ring, d->last_rx_ring, d->req.nr_rx_rings);
929 for (i = 0; i <= d->req.nr_tx_rings; i++) {
930 struct netmap_ring *r = NETMAP_TXRING(d->nifp, i);
931 D("TX%d %p h %d c %d t %d", i, r, r->head, r->cur, r->tail);
933 for (i = 0; i <= d->req.nr_rx_rings; i++) {
934 struct netmap_ring *r = NETMAP_RXRING(d->nifp, i);
935 D("RX%d %p h %d c %d t %d", i, r, r->head, r->cur, r->tail);
938 #endif /* debugging */
940 d->cur_tx_ring = d->first_tx_ring;
941 d->cur_rx_ring = d->first_rx_ring;
947 D("%s %s", errmsg, ifname);
955 nm_close(struct nm_desc *d)
958 * ugly trick to avoid unused warnings
960 static void *__xxzt[] __attribute__ ((unused)) =
961 { (void *)nm_open, (void *)nm_inject,
962 (void *)nm_dispatch, (void *)nm_nextpkt } ;
964 if (d == NULL || d->self != d)
966 if (d->done_mmap && d->mem)
967 munmap(d->mem, d->memsize);
972 bzero(d, sizeof(*d));
979 nm_mmap(struct nm_desc *d, const struct nm_desc *parent)
981 //XXX TODO: check if mmap is already done
983 if (IS_NETMAP_DESC(parent) && parent->mem &&
984 parent->req.nr_arg2 == d->req.nr_arg2) {
985 /* do not mmap, inherit from parent */
986 D("do not mmap, inherit from parent");
987 d->memsize = parent->memsize;
988 d->mem = parent->mem;
990 /* XXX TODO: check if memsize is too large (or there is overflow) */
991 d->memsize = d->req.nr_memsize;
992 d->mem = mmap(0, d->memsize, PROT_WRITE | PROT_READ, MAP_SHARED,
994 if (d->mem == MAP_FAILED) {
1000 struct netmap_if *nifp = NETMAP_IF(d->mem, d->req.nr_offset);
1001 struct netmap_ring *r = NETMAP_RXRING(nifp, d->first_rx_ring);
1002 if ((void *)r == (void *)nifp) {
1003 /* the descriptor is open for TX only */
1004 r = NETMAP_TXRING(nifp, d->first_tx_ring);
1007 *(struct netmap_if **)(uintptr_t)&(d->nifp) = nifp;
1008 *(struct netmap_ring **)(uintptr_t)&d->some_ring = r;
1009 *(void **)(uintptr_t)&d->buf_start = NETMAP_BUF(r, 0);
1010 *(void **)(uintptr_t)&d->buf_end =
1011 (char *)d->mem + d->memsize;
1021 * Same prototype as pcap_inject(), only need to cast.
1024 nm_inject(struct nm_desc *d, const void *buf, size_t size)
1026 u_int c, n = d->last_tx_ring - d->first_tx_ring + 1,
1027 ri = d->cur_tx_ring;
1029 for (c = 0; c < n ; c++, ri++) {
1030 /* compute current ring to use */
1031 struct netmap_ring *ring;
1034 if (ri > d->last_tx_ring)
1035 ri = d->first_tx_ring;
1036 ring = NETMAP_TXRING(d->nifp, ri);
1037 if (nm_ring_empty(ring)) {
1041 idx = ring->slot[i].buf_idx;
1042 ring->slot[i].len = size;
1043 nm_pkt_copy(buf, NETMAP_BUF(ring, idx), size);
1044 d->cur_tx_ring = ri;
1045 ring->head = ring->cur = nm_ring_next(ring, i);
1048 return 0; /* fail */
1053 * Same prototype as pcap_dispatch(), only need to cast.
1056 nm_dispatch(struct nm_desc *d, int cnt, nm_cb_t cb, u_char *arg)
1058 int n = d->last_rx_ring - d->first_rx_ring + 1;
1059 int c, got = 0, ri = d->cur_rx_ring;
1061 d->hdr.flags = NM_MORE_PKTS;
1066 /* cnt == -1 means infinite, but rings have a finite amount
1067 * of buffers and the int is large enough that we never wrap,
1068 * so we can omit checking for -1
1070 for (c=0; c < n && cnt != got; c++, ri++) {
1071 /* compute current ring to use */
1072 struct netmap_ring *ring;
1074 if (ri > d->last_rx_ring)
1075 ri = d->first_rx_ring;
1076 ring = NETMAP_RXRING(d->nifp, ri);
1077 for ( ; !nm_ring_empty(ring) && cnt != got; got++) {
1079 if (d->hdr.buf) { /* from previous round */
1080 cb(arg, &d->hdr, d->hdr.buf);
1083 idx = ring->slot[i].buf_idx;
1084 /* d->cur_rx_ring doesn't change inside this loop, but
1085 * set it here, so it reflects d->hdr.buf's ring */
1086 d->cur_rx_ring = ri;
1087 d->hdr.slot = &ring->slot[i];
1088 d->hdr.buf = (u_char *)NETMAP_BUF(ring, idx);
1089 // __builtin_prefetch(buf);
1090 d->hdr.len = d->hdr.caplen = ring->slot[i].len;
1091 d->hdr.ts = ring->ts;
1092 ring->head = ring->cur = nm_ring_next(ring, i);
1095 if (d->hdr.buf) { /* from previous round */
1097 cb(arg, &d->hdr, d->hdr.buf);
1103 nm_nextpkt(struct nm_desc *d, struct nm_pkthdr *hdr)
1105 int ri = d->cur_rx_ring;
1108 /* compute current ring to use */
1109 struct netmap_ring *ring = NETMAP_RXRING(d->nifp, ri);
1110 if (!nm_ring_empty(ring)) {
1111 u_int i = ring->cur;
1112 u_int idx = ring->slot[i].buf_idx;
1113 u_char *buf = (u_char *)NETMAP_BUF(ring, idx);
1115 // __builtin_prefetch(buf);
1117 hdr->len = hdr->caplen = ring->slot[i].len;
1118 ring->cur = nm_ring_next(ring, i);
1119 /* we could postpone advancing head if we want
1120 * to hold the buffer. This can be supported in
1123 ring->head = ring->cur;
1124 d->cur_rx_ring = ri;
1128 if (ri > d->last_rx_ring)
1129 ri = d->first_rx_ring;
1130 } while (ri != d->cur_rx_ring);
1131 return NULL; /* nothing found */
1134 #endif /* !HAVE_NETMAP_WITH_LIBS */
1136 #endif /* NETMAP_WITH_LIBS */
1138 #endif /* _NET_NETMAP_USER_H_ */