xref: /dflybsd-src/sys/net/netmap/netmap_freebsd.c (revision 572ff6f6e8b95055988f178b6ba12ce77bb5b3c2)
1 /*
2  * Copyright (C) 2013 Universita` di Pisa. All rights reserved.
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that the following conditions
6  * are met:
7  *   1. Redistributions of source code must retain the above copyright
8  *      notice, this list of conditions and the following disclaimer.
9  *   2. Redistributions in binary form must reproduce the above copyright
10  *      notice, this list of conditions and the following disclaimer in the
11  *      documentation and/or other materials provided with the distribution.
12  *
13  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
14  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
16  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
17  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
18  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
19  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
20  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
21  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
22  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
23  * SUCH DAMAGE.
24  */
25 
26 #include <sys/types.h>
27 #include <sys/module.h>
28 #include <sys/errno.h>
29 #include <sys/param.h>  /* defines used in kernel.h */
30 #include <sys/kernel.h> /* types used in module initialization */
31 #include <sys/conf.h>	/* DEV_MODULE */
32 #include <sys/devfs.h>
33 
34 #include <vm/vm.h>      /* vtophys */
35 #include <vm/pmap.h>    /* vtophys */
36 #include <vm/vm_param.h>
37 #include <vm/vm_object.h>
38 #include <vm/vm_page.h>
39 #include <vm/vm_page2.h>
40 #include <vm/vm_pager.h>
41 
42 
43 #include <sys/malloc.h>
44 #include <sys/socket.h> /* sockaddrs */
45 #include <sys/event.h>
46 #include <net/if.h>
47 #include <net/if_var.h>
48 #include <sys/bus.h>	/* bus_dmamap_* */
49 
50 #include <net/netmap.h>
51 #include "netmap_kern.h"
52 #include "netmap_mem2.h"
53 
54 
55 /* ======================== FREEBSD-SPECIFIC ROUTINES ================== */
56 
57 /*
58  * Intercept the rx routine in the standard device driver.
59  * Second argument is non-zero to intercept, 0 to restore
60  */
61 int
62 netmap_catch_rx(struct netmap_adapter *na, int intercept)
63 {
64 	struct netmap_generic_adapter *gna = (struct netmap_generic_adapter *)na;
65 	struct ifnet *ifp = na->ifp;
66 
67 	if (intercept) {
68 		if (gna->save_if_input) {
69 			D("cannot intercept again");
70 			return EINVAL; /* already set */
71 		}
72 		gna->save_if_input = ifp->if_input;
73 		ifp->if_input = generic_rx_handler;
74 	} else {
75 		if (!gna->save_if_input){
76 			D("cannot restore");
77 			return EINVAL;  /* not saved */
78 		}
79 		ifp->if_input = gna->save_if_input;
80 		gna->save_if_input = NULL;
81 	}
82 
83 	return 0;
84 }
85 
86 /*
87  * Intercept the packet steering routine in the tx path,
88  * so that we can decide which queue is used for an mbuf.
89  * Second argument is non-zero to intercept, 0 to restore.
90  *
91  * XXX see if FreeBSD has such a mechanism
92  */
93 void
94 netmap_catch_packet_steering(struct netmap_generic_adapter *na, int enable)
95 {
96 	if (enable) {
97 	} else {
98 	}
99 }
100 
101 /* Transmit routine used by generic_netmap_txsync(). Returns 0 on success
102  * and non-zero on error (which may be packet drops or other errors).
103  * addr and len identify the netmap buffer, m is the (preallocated)
104  * mbuf to use for transmissions.
105  *
106  * We should add a reference to the mbuf so the m_freem() at the end
107  * of the transmission does not consume resources.
108  *
109  * On FreeBSD, and on multiqueue cards, we can force the queue using
110  *      if ((m->m_flags & M_FLOWID) != 0)
111  *              i = m->m_pkthdr.flowid % adapter->num_queues;
112  *      else
113  *              i = curcpu % adapter->num_queues;
114  *
115  */
116 int
117 generic_xmit_frame(struct ifnet *ifp, struct mbuf *m,
118 	void *addr, u_int len, u_int ring_nr)
119 {
120 	int ret;
121 
122 	m->m_len = m->m_pkthdr.len = 0;
123 
124 	// copy data to the mbuf
125 	m_copyback(m, 0, len, addr);
126 
127 #if 0
128 	// inc refcount. We are alone, so we can skip the atomic
129 	atomic_fetchadd_int(m->m_ext.ref_cnt, 1);
130 	m->m_flags |= M_FLOWID;
131 #endif
132 	m->m_pkthdr.hash = ring_nr;	/* XXX probably not accurate */
133 	m->m_pkthdr.rcvif = ifp; /* used for tx notification */
134 	ret = ifp->if_transmit(ifp, m);
135 	return ret;
136 }
137 
138 /*
139  * The following two functions are empty until we have a generic
140  * way to extract the info from the ifp
141  */
142 int
143 generic_find_num_desc(struct ifnet *ifp, unsigned int *tx, unsigned int *rx)
144 {
145 	D("called");
146 	return 0;
147 }
148 
149 void
150 generic_find_num_queues(struct ifnet *ifp, u_int *txq, u_int *rxq)
151 {
152 	D("called");
153 	*txq = 1;
154 	*rxq = 1;
155 }
156 
157 void netmap_mitigation_init(struct netmap_generic_adapter *na)
158 {
159 	ND("called");
160 	na->mit_pending = 0;
161 }
162 
163 
164 void netmap_mitigation_start(struct netmap_generic_adapter *na)
165 {
166 	ND("called");
167 }
168 
169 void netmap_mitigation_restart(struct netmap_generic_adapter *na)
170 {
171 	ND("called");
172 }
173 
174 int netmap_mitigation_active(struct netmap_generic_adapter *na)
175 {
176 	ND("called");
177 	return 0;
178 }
179 
180 void netmap_mitigation_cleanup(struct netmap_generic_adapter *na)
181 {
182 	ND("called");
183 }
184 
185 
186 /*
187  * In order to track whether pages are still mapped, we hook into
188  * the standard cdev_pager and intercept the constructor and
189  * destructor.
190  */
191 
192 struct netmap_vm_handle_t {
193 	struct cdev 		*dev;
194 	struct netmap_priv_d	*priv;
195 };
196 
197 static int
198 netmap_dev_pager_ctor(void *handle, vm_ooffset_t size, vm_prot_t prot,
199     vm_ooffset_t foff, struct ucred *cred, u_short *color)
200 {
201 	struct netmap_vm_handle_t *vmh = handle;
202 	(void)vmh;
203 	D("handle %p size %jd prot %d foff %jd",
204 		handle, (intmax_t)size, prot, (intmax_t)foff);
205 #if 0
206 	dev_ref(vmh->dev);
207 #endif
208 	return 0;
209 }
210 
211 
212 static void
213 netmap_dev_pager_dtor(void *handle)
214 {
215 	struct netmap_vm_handle_t *vmh = handle;
216 	struct cdev *dev = vmh->dev;
217 	struct netmap_priv_d *priv = vmh->priv;
218 	(void)dev;
219 	D("handle %p", handle);
220 	netmap_dtor(priv);
221 	kfree(vmh, M_DEVBUF);
222 #if 0
223 	dev_rel(dev);
224 #endif
225 }
226 
227 static int
228 netmap_dev_pager_fault(vm_object_t object, vm_ooffset_t offset,
229 	int prot, vm_page_t *mres)
230 {
231 	struct netmap_vm_handle_t *vmh = object->handle;
232 	struct netmap_priv_d *priv = vmh->priv;
233 	vm_paddr_t paddr;
234 	vm_page_t page;
235 	vm_memattr_t memattr;
236 	vm_pindex_t pidx;
237 
238 	ND("object %p offset %jd prot %d mres %p",
239 			object, (intmax_t)offset, prot, mres);
240 	memattr = object->memattr;
241 	pidx = OFF_TO_IDX(offset);
242 	paddr = netmap_mem_ofstophys(priv->np_mref, offset);
243 	if (paddr == 0)
244 		return VM_PAGER_FAIL;
245 
246 	if (((*mres)->flags & PG_FICTITIOUS) != 0) {
247 		/*
248 		 * If the passed in result page is a fake page, update it with
249 		 * the new physical address.
250 		 */
251 		page = *mres;
252 		vm_page_updatefake(page, paddr, memattr);
253 	} else {
254 		/*
255 		 * Replace the passed in reqpage page with our own fake page and
256 		 * free up the all of the original pages.
257 		 */
258 #ifndef VM_OBJECT_WUNLOCK	/* FreeBSD < 10.x */
259 #define VM_OBJECT_WUNLOCK VM_OBJECT_UNLOCK
260 #define VM_OBJECT_WLOCK	VM_OBJECT_LOCK
261 #endif /* VM_OBJECT_WUNLOCK */
262 
263 		VM_OBJECT_WUNLOCK(object);
264 		page = vm_page_getfake(paddr, memattr);
265 		VM_OBJECT_WLOCK(object);
266 		vm_page_free(*mres);
267 		*mres = page;
268 		vm_page_insert(page, object, pidx);
269 	}
270 	page->valid = VM_PAGE_BITS_ALL;
271 	return (VM_PAGER_OK);
272 }
273 
274 
275 static struct cdev_pager_ops netmap_cdev_pager_ops = {
276 	.cdev_pg_ctor = netmap_dev_pager_ctor,
277 	.cdev_pg_dtor = netmap_dev_pager_dtor,
278 	.cdev_pg_fault = netmap_dev_pager_fault,
279 };
280 
281 
282 static int
283 netmap_mmap_single(struct dev_mmap_single_args *ap)
284 {
285 	int error;
286 	struct cdev *cdev = ap->a_head.a_dev;
287 	vm_ooffset_t *foff = ap->a_offset;
288 	vm_object_t *objp = ap->a_object;
289 	vm_size_t objsize = ap->a_size;
290 	struct netmap_vm_handle_t *vmh;
291 	struct netmap_priv_d *priv;
292 	int prot = ap->a_nprot;
293 	vm_object_t obj;
294 
295 	D("cdev %p foff %jd size %jd objp %p prot %d", cdev,
296 	    (intmax_t )*foff, (intmax_t )objsize, objp, prot);
297 
298 	vmh = kmalloc(sizeof(struct netmap_vm_handle_t), M_DEVBUF,
299 			      M_NOWAIT | M_ZERO);
300 	if (vmh == NULL)
301 		return ENOMEM;
302 	vmh->dev = cdev;
303 
304 	NMG_LOCK();
305 #if 0
306 	error = devfs_get_cdevpriv((void**)&priv);
307 	if (error)
308 		goto err_unlock;
309 #endif
310 	vmh->priv = priv;
311 	priv->np_refcount++;
312 	NMG_UNLOCK();
313 
314 	error = netmap_get_memory(priv);
315 	if (error)
316 		goto err_deref;
317 
318 	obj = cdev_pager_allocate(vmh, OBJT_DEVICE,
319 		&netmap_cdev_pager_ops, objsize, prot,
320 		*foff, NULL);
321 	if (obj == NULL) {
322 		D("cdev_pager_allocate failed");
323 		error = EINVAL;
324 		goto err_deref;
325 	}
326 
327 	*objp = obj;
328 	return 0;
329 
330 err_deref:
331 	NMG_LOCK();
332 	priv->np_refcount--;
333 #if 0
334 err_unlock:
335 #endif
336 	NMG_UNLOCK();
337 // err:
338 	kfree(vmh, M_DEVBUF);
339 	return error;
340 }
341 
342 
343 // XXX can we remove this ?
344 static int
345 netmap_close(struct dev_close_args *ap)
346 {
347 	if (netmap_verbose)
348 		D("dev %p fflag 0x%x devtype %d",
349 			ap->a_head.a_dev, ap->a_fflag, ap->a_devtype);
350 	return 0;
351 }
352 
353 
354 static int
355 netmap_open(struct dev_open_args *ap)
356 {
357 	struct netmap_priv_d *priv;
358 #if 0
359 	int error;
360 #endif
361 
362 	(void)ap;
363 
364 	// XXX wait or nowait ?
365 	priv = kmalloc(sizeof(struct netmap_priv_d), M_DEVBUF,
366 			      M_NOWAIT | M_ZERO);
367 	if (priv == NULL)
368 		return ENOMEM;
369 
370 #if 0
371 	error = devfs_set_cdevpriv(priv, netmap_dtor);
372 	if (error)
373 	        return error;
374 #endif
375 
376 	priv->np_refcount = 1;
377 
378 	return 0;
379 }
380 
381 
382 struct dev_ops netmap_cdevsw = {
383 	{ "netmap", 0, 0 },
384 	.d_open = netmap_open,
385 	.d_mmap_single = netmap_mmap_single,
386 	.d_ioctl = netmap_ioctl,
387 	.d_kqfilter = netmap_kqfilter,
388 	.d_close = netmap_close,
389 };
390 
391 
392 /*
393  * Kernel entry point.
394  *
395  * Initialize/finalize the module and return.
396  *
397  * Return 0 on success, errno on failure.
398  */
399 static int
400 netmap_loader(__unused struct module *module, int event, __unused void *arg)
401 {
402 	int error = 0;
403 
404 	switch (event) {
405 	case MOD_LOAD:
406 		error = netmap_init();
407 		break;
408 
409 	case MOD_UNLOAD:
410 		netmap_fini();
411 		break;
412 
413 	default:
414 		error = EOPNOTSUPP;
415 		break;
416 	}
417 
418 	return (error);
419 }
420 
421 
422 DEV_MODULE(netmap, netmap_loader, NULL);
423