xref: /freebsd/sys/dev/netmap/netmap_mem2.c (revision 11b249f99e4d4891bd2a21ef796d40073ee15508)
1 /*
2  * Copyright (C) 2012-2014 Matteo Landi, Luigi Rizzo, Giuseppe Lettieri. 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 #ifdef linux
27 #include "bsd_glue.h"
28 #endif /* linux */
29 
30 #ifdef __APPLE__
31 #include "osx_glue.h"
32 #endif /* __APPLE__ */
33 
34 #ifdef __FreeBSD__
35 #include <sys/cdefs.h> /* prerequisite */
36 __FBSDID("$FreeBSD$");
37 
38 #include <sys/types.h>
39 #include <sys/malloc.h>
40 #include <sys/proc.h>
41 #include <vm/vm.h>	/* vtophys */
42 #include <vm/pmap.h>	/* vtophys */
43 #include <sys/socket.h> /* sockaddrs */
44 #include <sys/selinfo.h>
45 #include <sys/sysctl.h>
46 #include <net/if.h>
47 #include <net/if_var.h>
48 #include <net/vnet.h>
49 #include <machine/bus.h>	/* bus_dmamap_* */
50 
51 #endif /* __FreeBSD__ */
52 
53 #include <net/netmap.h>
54 #include <dev/netmap/netmap_kern.h>
55 #include "netmap_mem2.h"
56 
57 #define NETMAP_BUF_MAX_NUM	20*4096*2	/* large machine */
58 
59 #define NETMAP_POOL_MAX_NAMSZ	32
60 
61 
62 enum {
63 	NETMAP_IF_POOL   = 0,
64 	NETMAP_RING_POOL,
65 	NETMAP_BUF_POOL,
66 	NETMAP_POOLS_NR
67 };
68 
69 
70 struct netmap_obj_params {
71 	u_int size;
72 	u_int num;
73 };
74 
75 struct netmap_obj_pool {
76 	char name[NETMAP_POOL_MAX_NAMSZ];	/* name of the allocator */
77 
78 	/* ---------------------------------------------------*/
79 	/* these are only meaningful if the pool is finalized */
80 	/* (see 'finalized' field in netmap_mem_d)            */
81 	u_int objtotal;         /* actual total number of objects. */
82 	u_int memtotal;		/* actual total memory space */
83 	u_int numclusters;	/* actual number of clusters */
84 
85 	u_int objfree;          /* number of free objects. */
86 
87 	struct lut_entry *lut;  /* virt,phys addresses, objtotal entries */
88 	uint32_t *bitmap;       /* one bit per buffer, 1 means free */
89 	uint32_t bitmap_slots;	/* number of uint32 entries in bitmap */
90 	/* ---------------------------------------------------*/
91 
92 	/* limits */
93 	u_int objminsize;	/* minimum object size */
94 	u_int objmaxsize;	/* maximum object size */
95 	u_int nummin;		/* minimum number of objects */
96 	u_int nummax;		/* maximum number of objects */
97 
98 	/* these are changed only by config */
99 	u_int _objtotal;	/* total number of objects */
100 	u_int _objsize;		/* object size */
101 	u_int _clustsize;       /* cluster size */
102 	u_int _clustentries;    /* objects per cluster */
103 	u_int _numclusters;	/* number of clusters */
104 
105 	/* requested values */
106 	u_int r_objtotal;
107 	u_int r_objsize;
108 };
109 
110 #define NMA_LOCK_T		NM_MTX_T
111 
112 
113 struct netmap_mem_ops {
114 	void (*nmd_get_lut)(struct netmap_mem_d *, struct netmap_lut*);
115 	int  (*nmd_get_info)(struct netmap_mem_d *, u_int *size,
116 			u_int *memflags, uint16_t *id);
117 
118 	vm_paddr_t (*nmd_ofstophys)(struct netmap_mem_d *, vm_ooffset_t);
119 	int (*nmd_config)(struct netmap_mem_d *);
120 	int (*nmd_finalize)(struct netmap_mem_d *);
121 	void (*nmd_deref)(struct netmap_mem_d *);
122 	ssize_t  (*nmd_if_offset)(struct netmap_mem_d *, const void *vaddr);
123 	void (*nmd_delete)(struct netmap_mem_d *);
124 
125 	struct netmap_if * (*nmd_if_new)(struct netmap_adapter *);
126 	void (*nmd_if_delete)(struct netmap_adapter *, struct netmap_if *);
127 	int  (*nmd_rings_create)(struct netmap_adapter *);
128 	void (*nmd_rings_delete)(struct netmap_adapter *);
129 };
130 
131 typedef uint16_t nm_memid_t;
132 
133 struct netmap_mem_d {
134 	NMA_LOCK_T nm_mtx;  /* protect the allocator */
135 	u_int nm_totalsize; /* shorthand */
136 
137 	u_int flags;
138 #define NETMAP_MEM_FINALIZED	0x1	/* preallocation done */
139 	int lasterr;		/* last error for curr config */
140 	int active;		/* active users */
141 	int refcount;
142 	/* the three allocators */
143 	struct netmap_obj_pool pools[NETMAP_POOLS_NR];
144 
145 	nm_memid_t nm_id;	/* allocator identifier */
146 	int nm_grp;	/* iommu groupd id */
147 
148 	/* list of all existing allocators, sorted by nm_id */
149 	struct netmap_mem_d *prev, *next;
150 
151 	struct netmap_mem_ops *ops;
152 };
153 
154 #define NMD_DEFCB(t0, name) \
155 t0 \
156 netmap_mem_##name(struct netmap_mem_d *nmd) \
157 { \
158 	return nmd->ops->nmd_##name(nmd); \
159 }
160 
161 #define NMD_DEFCB1(t0, name, t1) \
162 t0 \
163 netmap_mem_##name(struct netmap_mem_d *nmd, t1 a1) \
164 { \
165 	return nmd->ops->nmd_##name(nmd, a1); \
166 }
167 
168 #define NMD_DEFCB3(t0, name, t1, t2, t3) \
169 t0 \
170 netmap_mem_##name(struct netmap_mem_d *nmd, t1 a1, t2 a2, t3 a3) \
171 { \
172 	return nmd->ops->nmd_##name(nmd, a1, a2, a3); \
173 }
174 
175 #define NMD_DEFNACB(t0, name) \
176 t0 \
177 netmap_mem_##name(struct netmap_adapter *na) \
178 { \
179 	return na->nm_mem->ops->nmd_##name(na); \
180 }
181 
182 #define NMD_DEFNACB1(t0, name, t1) \
183 t0 \
184 netmap_mem_##name(struct netmap_adapter *na, t1 a1) \
185 { \
186 	return na->nm_mem->ops->nmd_##name(na, a1); \
187 }
188 
189 NMD_DEFCB1(void, get_lut, struct netmap_lut *);
190 NMD_DEFCB3(int, get_info, u_int *, u_int *, uint16_t *);
191 NMD_DEFCB1(vm_paddr_t, ofstophys, vm_ooffset_t);
192 static int netmap_mem_config(struct netmap_mem_d *);
193 NMD_DEFCB(int, config);
194 NMD_DEFCB1(ssize_t, if_offset, const void *);
195 NMD_DEFCB(void, delete);
196 
197 NMD_DEFNACB(struct netmap_if *, if_new);
198 NMD_DEFNACB1(void, if_delete, struct netmap_if *);
199 NMD_DEFNACB(int, rings_create);
200 NMD_DEFNACB(void, rings_delete);
201 
202 static int netmap_mem_map(struct netmap_obj_pool *, struct netmap_adapter *);
203 static int netmap_mem_unmap(struct netmap_obj_pool *, struct netmap_adapter *);
204 static int nm_mem_assign_group(struct netmap_mem_d *, struct device *);
205 
206 #define NMA_LOCK_INIT(n)	NM_MTX_INIT((n)->nm_mtx)
207 #define NMA_LOCK_DESTROY(n)	NM_MTX_DESTROY((n)->nm_mtx)
208 #define NMA_LOCK(n)		NM_MTX_LOCK((n)->nm_mtx)
209 #define NMA_UNLOCK(n)		NM_MTX_UNLOCK((n)->nm_mtx)
210 
211 #ifdef NM_DEBUG_MEM_PUTGET
212 #define NM_DBG_REFC(nmd, func, line)	\
213 	printf("%s:%d mem[%d] -> %d\n", func, line, (nmd)->nm_id, (nmd)->refcount);
214 #else
215 #define NM_DBG_REFC(nmd, func, line)
216 #endif
217 
218 #ifdef NM_DEBUG_MEM_PUTGET
219 void __netmap_mem_get(struct netmap_mem_d *nmd, const char *func, int line)
220 #else
221 void netmap_mem_get(struct netmap_mem_d *nmd)
222 #endif
223 {
224 	NMA_LOCK(nmd);
225 	nmd->refcount++;
226 	NM_DBG_REFC(nmd, func, line);
227 	NMA_UNLOCK(nmd);
228 }
229 
230 #ifdef NM_DEBUG_MEM_PUTGET
231 void __netmap_mem_put(struct netmap_mem_d *nmd, const char *func, int line)
232 #else
233 void netmap_mem_put(struct netmap_mem_d *nmd)
234 #endif
235 {
236 	int last;
237 	NMA_LOCK(nmd);
238 	last = (--nmd->refcount == 0);
239 	NM_DBG_REFC(nmd, func, line);
240 	NMA_UNLOCK(nmd);
241 	if (last)
242 		netmap_mem_delete(nmd);
243 }
244 
245 int
246 netmap_mem_finalize(struct netmap_mem_d *nmd, struct netmap_adapter *na)
247 {
248 	if (nm_mem_assign_group(nmd, na->pdev) < 0) {
249 		return ENOMEM;
250 	} else {
251 		nmd->ops->nmd_finalize(nmd);
252 	}
253 
254 	if (!nmd->lasterr && na->pdev)
255 		netmap_mem_map(&nmd->pools[NETMAP_BUF_POOL], na);
256 
257 	return nmd->lasterr;
258 }
259 
260 void
261 netmap_mem_deref(struct netmap_mem_d *nmd, struct netmap_adapter *na)
262 {
263 	NMA_LOCK(nmd);
264 	netmap_mem_unmap(&nmd->pools[NETMAP_BUF_POOL], na);
265 	NMA_UNLOCK(nmd);
266 	return nmd->ops->nmd_deref(nmd);
267 }
268 
269 
270 /* accessor functions */
271 static void
272 netmap_mem2_get_lut(struct netmap_mem_d *nmd, struct netmap_lut *lut)
273 {
274 	lut->lut = nmd->pools[NETMAP_BUF_POOL].lut;
275 	lut->objtotal = nmd->pools[NETMAP_BUF_POOL].objtotal;
276 	lut->objsize = nmd->pools[NETMAP_BUF_POOL]._objsize;
277 }
278 
279 struct netmap_obj_params netmap_params[NETMAP_POOLS_NR] = {
280 	[NETMAP_IF_POOL] = {
281 		.size = 1024,
282 		.num  = 100,
283 	},
284 	[NETMAP_RING_POOL] = {
285 		.size = 9*PAGE_SIZE,
286 		.num  = 200,
287 	},
288 	[NETMAP_BUF_POOL] = {
289 		.size = 2048,
290 		.num  = NETMAP_BUF_MAX_NUM,
291 	},
292 };
293 
294 struct netmap_obj_params netmap_min_priv_params[NETMAP_POOLS_NR] = {
295 	[NETMAP_IF_POOL] = {
296 		.size = 1024,
297 		.num  = 1,
298 	},
299 	[NETMAP_RING_POOL] = {
300 		.size = 5*PAGE_SIZE,
301 		.num  = 4,
302 	},
303 	[NETMAP_BUF_POOL] = {
304 		.size = 2048,
305 		.num  = 4098,
306 	},
307 };
308 
309 
310 /*
311  * nm_mem is the memory allocator used for all physical interfaces
312  * running in netmap mode.
313  * Virtual (VALE) ports will have each its own allocator.
314  */
315 extern struct netmap_mem_ops netmap_mem_global_ops; /* forward */
316 struct netmap_mem_d nm_mem = {	/* Our memory allocator. */
317 	.pools = {
318 		[NETMAP_IF_POOL] = {
319 			.name 	= "netmap_if",
320 			.objminsize = sizeof(struct netmap_if),
321 			.objmaxsize = 4096,
322 			.nummin     = 10,	/* don't be stingy */
323 			.nummax	    = 10000,	/* XXX very large */
324 		},
325 		[NETMAP_RING_POOL] = {
326 			.name 	= "netmap_ring",
327 			.objminsize = sizeof(struct netmap_ring),
328 			.objmaxsize = 32*PAGE_SIZE,
329 			.nummin     = 2,
330 			.nummax	    = 1024,
331 		},
332 		[NETMAP_BUF_POOL] = {
333 			.name	= "netmap_buf",
334 			.objminsize = 64,
335 			.objmaxsize = 65536,
336 			.nummin     = 4,
337 			.nummax	    = 1000000, /* one million! */
338 		},
339 	},
340 
341 	.nm_id = 1,
342 	.nm_grp = -1,
343 
344 	.prev = &nm_mem,
345 	.next = &nm_mem,
346 
347 	.ops = &netmap_mem_global_ops
348 };
349 
350 
351 struct netmap_mem_d *netmap_last_mem_d = &nm_mem;
352 
353 /* blueprint for the private memory allocators */
354 extern struct netmap_mem_ops netmap_mem_private_ops; /* forward */
355 const struct netmap_mem_d nm_blueprint = {
356 	.pools = {
357 		[NETMAP_IF_POOL] = {
358 			.name 	= "%s_if",
359 			.objminsize = sizeof(struct netmap_if),
360 			.objmaxsize = 4096,
361 			.nummin     = 1,
362 			.nummax	    = 100,
363 		},
364 		[NETMAP_RING_POOL] = {
365 			.name 	= "%s_ring",
366 			.objminsize = sizeof(struct netmap_ring),
367 			.objmaxsize = 32*PAGE_SIZE,
368 			.nummin     = 2,
369 			.nummax	    = 1024,
370 		},
371 		[NETMAP_BUF_POOL] = {
372 			.name	= "%s_buf",
373 			.objminsize = 64,
374 			.objmaxsize = 65536,
375 			.nummin     = 4,
376 			.nummax	    = 1000000, /* one million! */
377 		},
378 	},
379 
380 	.flags = NETMAP_MEM_PRIVATE,
381 
382 	.ops = &netmap_mem_private_ops
383 };
384 
385 /* memory allocator related sysctls */
386 
387 #define STRINGIFY(x) #x
388 
389 
390 #define DECLARE_SYSCTLS(id, name) \
391 	SYSCTL_INT(_dev_netmap, OID_AUTO, name##_size, \
392 	    CTLFLAG_RW, &netmap_params[id].size, 0, "Requested size of netmap " STRINGIFY(name) "s"); \
393 	SYSCTL_INT(_dev_netmap, OID_AUTO, name##_curr_size, \
394 	    CTLFLAG_RD, &nm_mem.pools[id]._objsize, 0, "Current size of netmap " STRINGIFY(name) "s"); \
395 	SYSCTL_INT(_dev_netmap, OID_AUTO, name##_num, \
396 	    CTLFLAG_RW, &netmap_params[id].num, 0, "Requested number of netmap " STRINGIFY(name) "s"); \
397 	SYSCTL_INT(_dev_netmap, OID_AUTO, name##_curr_num, \
398 	    CTLFLAG_RD, &nm_mem.pools[id].objtotal, 0, "Current number of netmap " STRINGIFY(name) "s"); \
399 	SYSCTL_INT(_dev_netmap, OID_AUTO, priv_##name##_size, \
400 	    CTLFLAG_RW, &netmap_min_priv_params[id].size, 0, \
401 	    "Default size of private netmap " STRINGIFY(name) "s"); \
402 	SYSCTL_INT(_dev_netmap, OID_AUTO, priv_##name##_num, \
403 	    CTLFLAG_RW, &netmap_min_priv_params[id].num, 0, \
404 	    "Default number of private netmap " STRINGIFY(name) "s")
405 
406 SYSCTL_DECL(_dev_netmap);
407 DECLARE_SYSCTLS(NETMAP_IF_POOL, if);
408 DECLARE_SYSCTLS(NETMAP_RING_POOL, ring);
409 DECLARE_SYSCTLS(NETMAP_BUF_POOL, buf);
410 
411 static int
412 nm_mem_assign_id(struct netmap_mem_d *nmd)
413 {
414 	nm_memid_t id;
415 	struct netmap_mem_d *scan = netmap_last_mem_d;
416 	int error = ENOMEM;
417 
418 	NMA_LOCK(&nm_mem);
419 
420 	do {
421 		/* we rely on unsigned wrap around */
422 		id = scan->nm_id + 1;
423 		if (id == 0) /* reserve 0 as error value */
424 			id = 1;
425 		scan = scan->next;
426 		if (id != scan->nm_id) {
427 			nmd->nm_id = id;
428 			nmd->prev = scan->prev;
429 			nmd->next = scan;
430 			scan->prev->next = nmd;
431 			scan->prev = nmd;
432 			netmap_last_mem_d = nmd;
433 			error = 0;
434 			break;
435 		}
436 	} while (scan != netmap_last_mem_d);
437 
438 	NMA_UNLOCK(&nm_mem);
439 	return error;
440 }
441 
442 static void
443 nm_mem_release_id(struct netmap_mem_d *nmd)
444 {
445 	NMA_LOCK(&nm_mem);
446 
447 	nmd->prev->next = nmd->next;
448 	nmd->next->prev = nmd->prev;
449 
450 	if (netmap_last_mem_d == nmd)
451 		netmap_last_mem_d = nmd->prev;
452 
453 	nmd->prev = nmd->next = NULL;
454 
455 	NMA_UNLOCK(&nm_mem);
456 }
457 
458 static int
459 nm_mem_assign_group(struct netmap_mem_d *nmd, struct device *dev)
460 {
461 	int err = 0, id;
462 	id = nm_iommu_group_id(dev);
463 	if (netmap_verbose)
464 		D("iommu_group %d", id);
465 
466 	NMA_LOCK(nmd);
467 
468 	if (nmd->nm_grp < 0)
469 		nmd->nm_grp = id;
470 
471 	if (nmd->nm_grp != id)
472 		nmd->lasterr = err = ENOMEM;
473 
474 	NMA_UNLOCK(nmd);
475 	return err;
476 }
477 
478 /*
479  * First, find the allocator that contains the requested offset,
480  * then locate the cluster through a lookup table.
481  */
482 static vm_paddr_t
483 netmap_mem2_ofstophys(struct netmap_mem_d* nmd, vm_ooffset_t offset)
484 {
485 	int i;
486 	vm_ooffset_t o = offset;
487 	vm_paddr_t pa;
488 	struct netmap_obj_pool *p;
489 
490 	NMA_LOCK(nmd);
491 	p = nmd->pools;
492 
493 	for (i = 0; i < NETMAP_POOLS_NR; offset -= p[i].memtotal, i++) {
494 		if (offset >= p[i].memtotal)
495 			continue;
496 		// now lookup the cluster's address
497 		pa = vtophys(p[i].lut[offset / p[i]._objsize].vaddr) +
498 			offset % p[i]._objsize;
499 		NMA_UNLOCK(nmd);
500 		return pa;
501 	}
502 	/* this is only in case of errors */
503 	D("invalid ofs 0x%x out of 0x%x 0x%x 0x%x", (u_int)o,
504 		p[NETMAP_IF_POOL].memtotal,
505 		p[NETMAP_IF_POOL].memtotal
506 			+ p[NETMAP_RING_POOL].memtotal,
507 		p[NETMAP_IF_POOL].memtotal
508 			+ p[NETMAP_RING_POOL].memtotal
509 			+ p[NETMAP_BUF_POOL].memtotal);
510 	NMA_UNLOCK(nmd);
511 	return 0;	// XXX bad address
512 }
513 
514 static int
515 netmap_mem2_get_info(struct netmap_mem_d* nmd, u_int* size, u_int *memflags,
516 	nm_memid_t *id)
517 {
518 	int error = 0;
519 	NMA_LOCK(nmd);
520 	error = netmap_mem_config(nmd);
521 	if (error)
522 		goto out;
523 	if (size) {
524 		if (nmd->flags & NETMAP_MEM_FINALIZED) {
525 			*size = nmd->nm_totalsize;
526 		} else {
527 			int i;
528 			*size = 0;
529 			for (i = 0; i < NETMAP_POOLS_NR; i++) {
530 				struct netmap_obj_pool *p = nmd->pools + i;
531 				*size += (p->_numclusters * p->_clustsize);
532 			}
533 		}
534 	}
535 	if (memflags)
536 		*memflags = nmd->flags;
537 	if (id)
538 		*id = nmd->nm_id;
539 out:
540 	NMA_UNLOCK(nmd);
541 	return error;
542 }
543 
544 /*
545  * we store objects by kernel address, need to find the offset
546  * within the pool to export the value to userspace.
547  * Algorithm: scan until we find the cluster, then add the
548  * actual offset in the cluster
549  */
550 static ssize_t
551 netmap_obj_offset(struct netmap_obj_pool *p, const void *vaddr)
552 {
553 	int i, k = p->_clustentries, n = p->objtotal;
554 	ssize_t ofs = 0;
555 
556 	for (i = 0; i < n; i += k, ofs += p->_clustsize) {
557 		const char *base = p->lut[i].vaddr;
558 		ssize_t relofs = (const char *) vaddr - base;
559 
560 		if (relofs < 0 || relofs >= p->_clustsize)
561 			continue;
562 
563 		ofs = ofs + relofs;
564 		ND("%s: return offset %d (cluster %d) for pointer %p",
565 		    p->name, ofs, i, vaddr);
566 		return ofs;
567 	}
568 	D("address %p is not contained inside any cluster (%s)",
569 	    vaddr, p->name);
570 	return 0; /* An error occurred */
571 }
572 
573 /* Helper functions which convert virtual addresses to offsets */
574 #define netmap_if_offset(n, v)					\
575 	netmap_obj_offset(&(n)->pools[NETMAP_IF_POOL], (v))
576 
577 #define netmap_ring_offset(n, v)				\
578     ((n)->pools[NETMAP_IF_POOL].memtotal + 			\
579 	netmap_obj_offset(&(n)->pools[NETMAP_RING_POOL], (v)))
580 
581 #define netmap_buf_offset(n, v)					\
582     ((n)->pools[NETMAP_IF_POOL].memtotal +			\
583 	(n)->pools[NETMAP_RING_POOL].memtotal +		\
584 	netmap_obj_offset(&(n)->pools[NETMAP_BUF_POOL], (v)))
585 
586 
587 static ssize_t
588 netmap_mem2_if_offset(struct netmap_mem_d *nmd, const void *addr)
589 {
590 	ssize_t v;
591 	NMA_LOCK(nmd);
592 	v = netmap_if_offset(nmd, addr);
593 	NMA_UNLOCK(nmd);
594 	return v;
595 }
596 
597 /*
598  * report the index, and use start position as a hint,
599  * otherwise buffer allocation becomes terribly expensive.
600  */
601 static void *
602 netmap_obj_malloc(struct netmap_obj_pool *p, u_int len, uint32_t *start, uint32_t *index)
603 {
604 	uint32_t i = 0;			/* index in the bitmap */
605 	uint32_t mask, j;		/* slot counter */
606 	void *vaddr = NULL;
607 
608 	if (len > p->_objsize) {
609 		D("%s request size %d too large", p->name, len);
610 		// XXX cannot reduce the size
611 		return NULL;
612 	}
613 
614 	if (p->objfree == 0) {
615 		D("no more %s objects", p->name);
616 		return NULL;
617 	}
618 	if (start)
619 		i = *start;
620 
621 	/* termination is guaranteed by p->free, but better check bounds on i */
622 	while (vaddr == NULL && i < p->bitmap_slots)  {
623 		uint32_t cur = p->bitmap[i];
624 		if (cur == 0) { /* bitmask is fully used */
625 			i++;
626 			continue;
627 		}
628 		/* locate a slot */
629 		for (j = 0, mask = 1; (cur & mask) == 0; j++, mask <<= 1)
630 			;
631 
632 		p->bitmap[i] &= ~mask; /* mark object as in use */
633 		p->objfree--;
634 
635 		vaddr = p->lut[i * 32 + j].vaddr;
636 		if (index)
637 			*index = i * 32 + j;
638 	}
639 	ND("%s allocator: allocated object @ [%d][%d]: vaddr %p", i, j, vaddr);
640 
641 	if (start)
642 		*start = i;
643 	return vaddr;
644 }
645 
646 
647 /*
648  * free by index, not by address.
649  * XXX should we also cleanup the content ?
650  */
651 static int
652 netmap_obj_free(struct netmap_obj_pool *p, uint32_t j)
653 {
654 	uint32_t *ptr, mask;
655 
656 	if (j >= p->objtotal) {
657 		D("invalid index %u, max %u", j, p->objtotal);
658 		return 1;
659 	}
660 	ptr = &p->bitmap[j / 32];
661 	mask = (1 << (j % 32));
662 	if (*ptr & mask) {
663 		D("ouch, double free on buffer %d", j);
664 		return 1;
665 	} else {
666 		*ptr |= mask;
667 		p->objfree++;
668 		return 0;
669 	}
670 }
671 
672 /*
673  * free by address. This is slow but is only used for a few
674  * objects (rings, nifp)
675  */
676 static void
677 netmap_obj_free_va(struct netmap_obj_pool *p, void *vaddr)
678 {
679 	u_int i, j, n = p->numclusters;
680 
681 	for (i = 0, j = 0; i < n; i++, j += p->_clustentries) {
682 		void *base = p->lut[i * p->_clustentries].vaddr;
683 		ssize_t relofs = (ssize_t) vaddr - (ssize_t) base;
684 
685 		/* Given address, is out of the scope of the current cluster.*/
686 		if (vaddr < base || relofs >= p->_clustsize)
687 			continue;
688 
689 		j = j + relofs / p->_objsize;
690 		/* KASSERT(j != 0, ("Cannot free object 0")); */
691 		netmap_obj_free(p, j);
692 		return;
693 	}
694 	D("address %p is not contained inside any cluster (%s)",
695 	    vaddr, p->name);
696 }
697 
698 #define netmap_mem_bufsize(n)	\
699 	((n)->pools[NETMAP_BUF_POOL]._objsize)
700 
701 #define netmap_if_malloc(n, len)	netmap_obj_malloc(&(n)->pools[NETMAP_IF_POOL], len, NULL, NULL)
702 #define netmap_if_free(n, v)		netmap_obj_free_va(&(n)->pools[NETMAP_IF_POOL], (v))
703 #define netmap_ring_malloc(n, len)	netmap_obj_malloc(&(n)->pools[NETMAP_RING_POOL], len, NULL, NULL)
704 #define netmap_ring_free(n, v)		netmap_obj_free_va(&(n)->pools[NETMAP_RING_POOL], (v))
705 #define netmap_buf_malloc(n, _pos, _index)			\
706 	netmap_obj_malloc(&(n)->pools[NETMAP_BUF_POOL], netmap_mem_bufsize(n), _pos, _index)
707 
708 
709 #if 0 // XXX unused
710 /* Return the index associated to the given packet buffer */
711 #define netmap_buf_index(n, v)						\
712     (netmap_obj_offset(&(n)->pools[NETMAP_BUF_POOL], (v)) / NETMAP_BDG_BUF_SIZE(n))
713 #endif
714 
715 /*
716  * allocate extra buffers in a linked list.
717  * returns the actual number.
718  */
719 uint32_t
720 netmap_extra_alloc(struct netmap_adapter *na, uint32_t *head, uint32_t n)
721 {
722 	struct netmap_mem_d *nmd = na->nm_mem;
723 	uint32_t i, pos = 0; /* opaque, scan position in the bitmap */
724 
725 	NMA_LOCK(nmd);
726 
727 	*head = 0;	/* default, 'null' index ie empty list */
728 	for (i = 0 ; i < n; i++) {
729 		uint32_t cur = *head;	/* save current head */
730 		uint32_t *p = netmap_buf_malloc(nmd, &pos, head);
731 		if (p == NULL) {
732 			D("no more buffers after %d of %d", i, n);
733 			*head = cur; /* restore */
734 			break;
735 		}
736 		RD(5, "allocate buffer %d -> %d", *head, cur);
737 		*p = cur; /* link to previous head */
738 	}
739 
740 	NMA_UNLOCK(nmd);
741 
742 	return i;
743 }
744 
745 static void
746 netmap_extra_free(struct netmap_adapter *na, uint32_t head)
747 {
748         struct lut_entry *lut = na->na_lut.lut;
749 	struct netmap_mem_d *nmd = na->nm_mem;
750 	struct netmap_obj_pool *p = &nmd->pools[NETMAP_BUF_POOL];
751 	uint32_t i, cur, *buf;
752 
753 	D("freeing the extra list");
754 	for (i = 0; head >=2 && head < p->objtotal; i++) {
755 		cur = head;
756 		buf = lut[head].vaddr;
757 		head = *buf;
758 		*buf = 0;
759 		if (netmap_obj_free(p, cur))
760 			break;
761 	}
762 	if (head != 0)
763 		D("breaking with head %d", head);
764 	D("freed %d buffers", i);
765 }
766 
767 
768 /* Return nonzero on error */
769 static int
770 netmap_new_bufs(struct netmap_mem_d *nmd, struct netmap_slot *slot, u_int n)
771 {
772 	struct netmap_obj_pool *p = &nmd->pools[NETMAP_BUF_POOL];
773 	u_int i = 0;	/* slot counter */
774 	uint32_t pos = 0;	/* slot in p->bitmap */
775 	uint32_t index = 0;	/* buffer index */
776 
777 	for (i = 0; i < n; i++) {
778 		void *vaddr = netmap_buf_malloc(nmd, &pos, &index);
779 		if (vaddr == NULL) {
780 			D("no more buffers after %d of %d", i, n);
781 			goto cleanup;
782 		}
783 		slot[i].buf_idx = index;
784 		slot[i].len = p->_objsize;
785 		slot[i].flags = 0;
786 	}
787 
788 	ND("allocated %d buffers, %d available, first at %d", n, p->objfree, pos);
789 	return (0);
790 
791 cleanup:
792 	while (i > 0) {
793 		i--;
794 		netmap_obj_free(p, slot[i].buf_idx);
795 	}
796 	bzero(slot, n * sizeof(slot[0]));
797 	return (ENOMEM);
798 }
799 
800 static void
801 netmap_mem_set_ring(struct netmap_mem_d *nmd, struct netmap_slot *slot, u_int n, uint32_t index)
802 {
803 	struct netmap_obj_pool *p = &nmd->pools[NETMAP_BUF_POOL];
804 	u_int i;
805 
806 	for (i = 0; i < n; i++) {
807 		slot[i].buf_idx = index;
808 		slot[i].len = p->_objsize;
809 		slot[i].flags = 0;
810 	}
811 }
812 
813 
814 static void
815 netmap_free_buf(struct netmap_mem_d *nmd, uint32_t i)
816 {
817 	struct netmap_obj_pool *p = &nmd->pools[NETMAP_BUF_POOL];
818 
819 	if (i < 2 || i >= p->objtotal) {
820 		D("Cannot free buf#%d: should be in [2, %d[", i, p->objtotal);
821 		return;
822 	}
823 	netmap_obj_free(p, i);
824 }
825 
826 
827 static void
828 netmap_free_bufs(struct netmap_mem_d *nmd, struct netmap_slot *slot, u_int n)
829 {
830 	u_int i;
831 
832 	for (i = 0; i < n; i++) {
833 		if (slot[i].buf_idx > 2)
834 			netmap_free_buf(nmd, slot[i].buf_idx);
835 	}
836 }
837 
838 static void
839 netmap_reset_obj_allocator(struct netmap_obj_pool *p)
840 {
841 
842 	if (p == NULL)
843 		return;
844 	if (p->bitmap)
845 		free(p->bitmap, M_NETMAP);
846 	p->bitmap = NULL;
847 	if (p->lut) {
848 		u_int i;
849 		size_t sz = p->_clustsize;
850 
851 		/*
852 		 * Free each cluster allocated in
853 		 * netmap_finalize_obj_allocator().  The cluster start
854 		 * addresses are stored at multiples of p->_clusterentries
855 		 * in the lut.
856 		 */
857 		for (i = 0; i < p->objtotal; i += p->_clustentries) {
858 			if (p->lut[i].vaddr)
859 				contigfree(p->lut[i].vaddr, sz, M_NETMAP);
860 		}
861 		bzero(p->lut, sizeof(struct lut_entry) * p->objtotal);
862 #ifdef linux
863 		vfree(p->lut);
864 #else
865 		free(p->lut, M_NETMAP);
866 #endif
867 	}
868 	p->lut = NULL;
869 	p->objtotal = 0;
870 	p->memtotal = 0;
871 	p->numclusters = 0;
872 	p->objfree = 0;
873 }
874 
875 /*
876  * Free all resources related to an allocator.
877  */
878 static void
879 netmap_destroy_obj_allocator(struct netmap_obj_pool *p)
880 {
881 	if (p == NULL)
882 		return;
883 	netmap_reset_obj_allocator(p);
884 }
885 
886 /*
887  * We receive a request for objtotal objects, of size objsize each.
888  * Internally we may round up both numbers, as we allocate objects
889  * in small clusters multiple of the page size.
890  * We need to keep track of objtotal and clustentries,
891  * as they are needed when freeing memory.
892  *
893  * XXX note -- userspace needs the buffers to be contiguous,
894  *	so we cannot afford gaps at the end of a cluster.
895  */
896 
897 
898 /* call with NMA_LOCK held */
899 static int
900 netmap_config_obj_allocator(struct netmap_obj_pool *p, u_int objtotal, u_int objsize)
901 {
902 	int i;
903 	u_int clustsize;	/* the cluster size, multiple of page size */
904 	u_int clustentries;	/* how many objects per entry */
905 
906 	/* we store the current request, so we can
907 	 * detect configuration changes later */
908 	p->r_objtotal = objtotal;
909 	p->r_objsize = objsize;
910 
911 #define MAX_CLUSTSIZE	(1<<22)		// 4 MB
912 #define LINE_ROUND	NM_CACHE_ALIGN	// 64
913 	if (objsize >= MAX_CLUSTSIZE) {
914 		/* we could do it but there is no point */
915 		D("unsupported allocation for %d bytes", objsize);
916 		return EINVAL;
917 	}
918 	/* make sure objsize is a multiple of LINE_ROUND */
919 	i = (objsize & (LINE_ROUND - 1));
920 	if (i) {
921 		D("XXX aligning object by %d bytes", LINE_ROUND - i);
922 		objsize += LINE_ROUND - i;
923 	}
924 	if (objsize < p->objminsize || objsize > p->objmaxsize) {
925 		D("requested objsize %d out of range [%d, %d]",
926 			objsize, p->objminsize, p->objmaxsize);
927 		return EINVAL;
928 	}
929 	if (objtotal < p->nummin || objtotal > p->nummax) {
930 		D("requested objtotal %d out of range [%d, %d]",
931 			objtotal, p->nummin, p->nummax);
932 		return EINVAL;
933 	}
934 	/*
935 	 * Compute number of objects using a brute-force approach:
936 	 * given a max cluster size,
937 	 * we try to fill it with objects keeping track of the
938 	 * wasted space to the next page boundary.
939 	 */
940 	for (clustentries = 0, i = 1;; i++) {
941 		u_int delta, used = i * objsize;
942 		if (used > MAX_CLUSTSIZE)
943 			break;
944 		delta = used % PAGE_SIZE;
945 		if (delta == 0) { // exact solution
946 			clustentries = i;
947 			break;
948 		}
949 	}
950 	/* exact solution not found */
951 	if (clustentries == 0) {
952 		D("unsupported allocation for %d bytes", objsize);
953 		return EINVAL;
954 	}
955 	/* compute clustsize */
956 	clustsize = clustentries * objsize;
957 	if (netmap_verbose)
958 		D("objsize %d clustsize %d objects %d",
959 			objsize, clustsize, clustentries);
960 
961 	/*
962 	 * The number of clusters is n = ceil(objtotal/clustentries)
963 	 * objtotal' = n * clustentries
964 	 */
965 	p->_clustentries = clustentries;
966 	p->_clustsize = clustsize;
967 	p->_numclusters = (objtotal + clustentries - 1) / clustentries;
968 
969 	/* actual values (may be larger than requested) */
970 	p->_objsize = objsize;
971 	p->_objtotal = p->_numclusters * clustentries;
972 
973 	return 0;
974 }
975 
976 
977 /* call with NMA_LOCK held */
978 static int
979 netmap_finalize_obj_allocator(struct netmap_obj_pool *p)
980 {
981 	int i; /* must be signed */
982 	size_t n;
983 
984 	/* optimistically assume we have enough memory */
985 	p->numclusters = p->_numclusters;
986 	p->objtotal = p->_objtotal;
987 
988 	n = sizeof(struct lut_entry) * p->objtotal;
989 #ifdef linux
990 	p->lut = vmalloc(n);
991 #else
992 	p->lut = malloc(n, M_NETMAP, M_NOWAIT | M_ZERO);
993 #endif
994 	if (p->lut == NULL) {
995 		D("Unable to create lookup table (%d bytes) for '%s'", (int)n, p->name);
996 		goto clean;
997 	}
998 
999 	/* Allocate the bitmap */
1000 	n = (p->objtotal + 31) / 32;
1001 	p->bitmap = malloc(sizeof(uint32_t) * n, M_NETMAP, M_NOWAIT | M_ZERO);
1002 	if (p->bitmap == NULL) {
1003 		D("Unable to create bitmap (%d entries) for allocator '%s'", (int)n,
1004 		    p->name);
1005 		goto clean;
1006 	}
1007 	p->bitmap_slots = n;
1008 
1009 	/*
1010 	 * Allocate clusters, init pointers and bitmap
1011 	 */
1012 
1013 	n = p->_clustsize;
1014 	for (i = 0; i < (int)p->objtotal;) {
1015 		int lim = i + p->_clustentries;
1016 		char *clust;
1017 
1018 		clust = contigmalloc(n, M_NETMAP, M_NOWAIT | M_ZERO,
1019 		    (size_t)0, -1UL, PAGE_SIZE, 0);
1020 		if (clust == NULL) {
1021 			/*
1022 			 * If we get here, there is a severe memory shortage,
1023 			 * so halve the allocated memory to reclaim some.
1024 			 */
1025 			D("Unable to create cluster at %d for '%s' allocator",
1026 			    i, p->name);
1027 			if (i < 2) /* nothing to halve */
1028 				goto out;
1029 			lim = i / 2;
1030 			for (i--; i >= lim; i--) {
1031 				p->bitmap[ (i>>5) ] &=  ~( 1 << (i & 31) );
1032 				if (i % p->_clustentries == 0 && p->lut[i].vaddr)
1033 					contigfree(p->lut[i].vaddr,
1034 						n, M_NETMAP);
1035 				p->lut[i].vaddr = NULL;
1036 			}
1037 		out:
1038 			p->objtotal = i;
1039 			/* we may have stopped in the middle of a cluster */
1040 			p->numclusters = (i + p->_clustentries - 1) / p->_clustentries;
1041 			break;
1042 		}
1043 		/*
1044 		 * Set bitmap and lut state for all buffers in the current
1045 		 * cluster.
1046 		 *
1047 		 * [i, lim) is the set of buffer indexes that cover the
1048 		 * current cluster.
1049 		 *
1050 		 * 'clust' is really the address of the current buffer in
1051 		 * the current cluster as we index through it with a stride
1052 		 * of p->_objsize.
1053 		 */
1054 		for (; i < lim; i++, clust += p->_objsize) {
1055 			p->bitmap[ (i>>5) ] |=  ( 1 << (i & 31) );
1056 			p->lut[i].vaddr = clust;
1057 			p->lut[i].paddr = vtophys(clust);
1058 		}
1059 	}
1060 	p->objfree = p->objtotal;
1061 	p->memtotal = p->numclusters * p->_clustsize;
1062 	if (p->objfree == 0)
1063 		goto clean;
1064 	if (netmap_verbose)
1065 		D("Pre-allocated %d clusters (%d/%dKB) for '%s'",
1066 		    p->numclusters, p->_clustsize >> 10,
1067 		    p->memtotal >> 10, p->name);
1068 
1069 	return 0;
1070 
1071 clean:
1072 	netmap_reset_obj_allocator(p);
1073 	return ENOMEM;
1074 }
1075 
1076 /* call with lock held */
1077 static int
1078 netmap_memory_config_changed(struct netmap_mem_d *nmd)
1079 {
1080 	int i;
1081 
1082 	for (i = 0; i < NETMAP_POOLS_NR; i++) {
1083 		if (nmd->pools[i].r_objsize != netmap_params[i].size ||
1084 		    nmd->pools[i].r_objtotal != netmap_params[i].num)
1085 		    return 1;
1086 	}
1087 	return 0;
1088 }
1089 
1090 static void
1091 netmap_mem_reset_all(struct netmap_mem_d *nmd)
1092 {
1093 	int i;
1094 
1095 	if (netmap_verbose)
1096 		D("resetting %p", nmd);
1097 	for (i = 0; i < NETMAP_POOLS_NR; i++) {
1098 		netmap_reset_obj_allocator(&nmd->pools[i]);
1099 	}
1100 	nmd->flags  &= ~NETMAP_MEM_FINALIZED;
1101 }
1102 
1103 static int
1104 netmap_mem_unmap(struct netmap_obj_pool *p, struct netmap_adapter *na)
1105 {
1106 	int i, lim = p->_objtotal;
1107 
1108 	if (na->pdev == NULL)
1109 		return 0;
1110 
1111 #ifdef __FreeBSD__
1112 	(void)i;
1113 	(void)lim;
1114 	D("unsupported on FreeBSD");
1115 #else /* linux */
1116 	for (i = 2; i < lim; i++) {
1117 		netmap_unload_map(na, (bus_dma_tag_t) na->pdev, &p->lut[i].paddr);
1118 	}
1119 #endif /* linux */
1120 
1121 	return 0;
1122 }
1123 
1124 static int
1125 netmap_mem_map(struct netmap_obj_pool *p, struct netmap_adapter *na)
1126 {
1127 #ifdef __FreeBSD__
1128 	D("unsupported on FreeBSD");
1129 #else /* linux */
1130 	int i, lim = p->_objtotal;
1131 
1132 	if (na->pdev == NULL)
1133 		return 0;
1134 
1135 	for (i = 2; i < lim; i++) {
1136 		netmap_load_map(na, (bus_dma_tag_t) na->pdev, &p->lut[i].paddr,
1137 				p->lut[i].vaddr);
1138 	}
1139 #endif /* linux */
1140 
1141 	return 0;
1142 }
1143 
1144 static int
1145 netmap_mem_finalize_all(struct netmap_mem_d *nmd)
1146 {
1147 	int i;
1148 	if (nmd->flags & NETMAP_MEM_FINALIZED)
1149 		return 0;
1150 	nmd->lasterr = 0;
1151 	nmd->nm_totalsize = 0;
1152 	for (i = 0; i < NETMAP_POOLS_NR; i++) {
1153 		nmd->lasterr = netmap_finalize_obj_allocator(&nmd->pools[i]);
1154 		if (nmd->lasterr)
1155 			goto error;
1156 		nmd->nm_totalsize += nmd->pools[i].memtotal;
1157 	}
1158 	/* buffers 0 and 1 are reserved */
1159 	nmd->pools[NETMAP_BUF_POOL].objfree -= 2;
1160 	nmd->pools[NETMAP_BUF_POOL].bitmap[0] = ~3;
1161 	nmd->flags |= NETMAP_MEM_FINALIZED;
1162 
1163 	if (netmap_verbose)
1164 		D("interfaces %d KB, rings %d KB, buffers %d MB",
1165 		    nmd->pools[NETMAP_IF_POOL].memtotal >> 10,
1166 		    nmd->pools[NETMAP_RING_POOL].memtotal >> 10,
1167 		    nmd->pools[NETMAP_BUF_POOL].memtotal >> 20);
1168 
1169 	if (netmap_verbose)
1170 		D("Free buffers: %d", nmd->pools[NETMAP_BUF_POOL].objfree);
1171 
1172 
1173 	return 0;
1174 error:
1175 	netmap_mem_reset_all(nmd);
1176 	return nmd->lasterr;
1177 }
1178 
1179 
1180 
1181 static void
1182 netmap_mem_private_delete(struct netmap_mem_d *nmd)
1183 {
1184 	if (nmd == NULL)
1185 		return;
1186 	if (netmap_verbose)
1187 		D("deleting %p", nmd);
1188 	if (nmd->active > 0)
1189 		D("bug: deleting mem allocator with active=%d!", nmd->active);
1190 	nm_mem_release_id(nmd);
1191 	if (netmap_verbose)
1192 		D("done deleting %p", nmd);
1193 	NMA_LOCK_DESTROY(nmd);
1194 	free(nmd, M_DEVBUF);
1195 }
1196 
1197 static int
1198 netmap_mem_private_config(struct netmap_mem_d *nmd)
1199 {
1200 	/* nothing to do, we are configured on creation
1201  	 * and configuration never changes thereafter
1202  	 */
1203 	return 0;
1204 }
1205 
1206 static int
1207 netmap_mem_private_finalize(struct netmap_mem_d *nmd)
1208 {
1209 	int err;
1210 	NMA_LOCK(nmd);
1211 	nmd->active++;
1212 	err = netmap_mem_finalize_all(nmd);
1213 	NMA_UNLOCK(nmd);
1214 	return err;
1215 
1216 }
1217 
1218 static void
1219 netmap_mem_private_deref(struct netmap_mem_d *nmd)
1220 {
1221 	NMA_LOCK(nmd);
1222 	if (--nmd->active <= 0)
1223 		netmap_mem_reset_all(nmd);
1224 	NMA_UNLOCK(nmd);
1225 }
1226 
1227 
1228 /*
1229  * allocator for private memory
1230  */
1231 struct netmap_mem_d *
1232 netmap_mem_private_new(const char *name, u_int txr, u_int txd,
1233 	u_int rxr, u_int rxd, u_int extra_bufs, u_int npipes, int *perr)
1234 {
1235 	struct netmap_mem_d *d = NULL;
1236 	struct netmap_obj_params p[NETMAP_POOLS_NR];
1237 	int i, err;
1238 	u_int v, maxd;
1239 
1240 	d = malloc(sizeof(struct netmap_mem_d),
1241 			M_DEVBUF, M_NOWAIT | M_ZERO);
1242 	if (d == NULL) {
1243 		err = ENOMEM;
1244 		goto error;
1245 	}
1246 
1247 	*d = nm_blueprint;
1248 
1249 	err = nm_mem_assign_id(d);
1250 	if (err)
1251 		goto error;
1252 
1253 	/* account for the fake host rings */
1254 	txr++;
1255 	rxr++;
1256 
1257 	/* copy the min values */
1258 	for (i = 0; i < NETMAP_POOLS_NR; i++) {
1259 		p[i] = netmap_min_priv_params[i];
1260 	}
1261 
1262 	/* possibly increase them to fit user request */
1263 	v = sizeof(struct netmap_if) + sizeof(ssize_t) * (txr + rxr);
1264 	if (p[NETMAP_IF_POOL].size < v)
1265 		p[NETMAP_IF_POOL].size = v;
1266 	v = 2 + 4 * npipes;
1267 	if (p[NETMAP_IF_POOL].num < v)
1268 		p[NETMAP_IF_POOL].num = v;
1269 	maxd = (txd > rxd) ? txd : rxd;
1270 	v = sizeof(struct netmap_ring) + sizeof(struct netmap_slot) * maxd;
1271 	if (p[NETMAP_RING_POOL].size < v)
1272 		p[NETMAP_RING_POOL].size = v;
1273 	/* each pipe endpoint needs two tx rings (1 normal + 1 host, fake)
1274          * and two rx rings (again, 1 normal and 1 fake host)
1275          */
1276 	v = txr + rxr + 8 * npipes;
1277 	if (p[NETMAP_RING_POOL].num < v)
1278 		p[NETMAP_RING_POOL].num = v;
1279 	/* for each pipe we only need the buffers for the 4 "real" rings.
1280          * On the other end, the pipe ring dimension may be different from
1281          * the parent port ring dimension. As a compromise, we allocate twice the
1282          * space actually needed if the pipe rings were the same size as the parent rings
1283          */
1284 	v = (4 * npipes + rxr) * rxd + (4 * npipes + txr) * txd + 2 + extra_bufs;
1285 		/* the +2 is for the tx and rx fake buffers (indices 0 and 1) */
1286 	if (p[NETMAP_BUF_POOL].num < v)
1287 		p[NETMAP_BUF_POOL].num = v;
1288 
1289 	if (netmap_verbose)
1290 		D("req if %d*%d ring %d*%d buf %d*%d",
1291 			p[NETMAP_IF_POOL].num,
1292 			p[NETMAP_IF_POOL].size,
1293 			p[NETMAP_RING_POOL].num,
1294 			p[NETMAP_RING_POOL].size,
1295 			p[NETMAP_BUF_POOL].num,
1296 			p[NETMAP_BUF_POOL].size);
1297 
1298 	for (i = 0; i < NETMAP_POOLS_NR; i++) {
1299 		snprintf(d->pools[i].name, NETMAP_POOL_MAX_NAMSZ,
1300 				nm_blueprint.pools[i].name,
1301 				name);
1302 		err = netmap_config_obj_allocator(&d->pools[i],
1303 				p[i].num, p[i].size);
1304 		if (err)
1305 			goto error;
1306 	}
1307 
1308 	d->flags &= ~NETMAP_MEM_FINALIZED;
1309 
1310 	NMA_LOCK_INIT(d);
1311 
1312 	return d;
1313 error:
1314 	netmap_mem_private_delete(d);
1315 	if (perr)
1316 		*perr = err;
1317 	return NULL;
1318 }
1319 
1320 
1321 /* call with lock held */
1322 static int
1323 netmap_mem_global_config(struct netmap_mem_d *nmd)
1324 {
1325 	int i;
1326 
1327 	if (nmd->active)
1328 		/* already in use, we cannot change the configuration */
1329 		goto out;
1330 
1331 	if (!netmap_memory_config_changed(nmd))
1332 		goto out;
1333 
1334 	ND("reconfiguring");
1335 
1336 	if (nmd->flags & NETMAP_MEM_FINALIZED) {
1337 		/* reset previous allocation */
1338 		for (i = 0; i < NETMAP_POOLS_NR; i++) {
1339 			netmap_reset_obj_allocator(&nmd->pools[i]);
1340 		}
1341 		nmd->flags &= ~NETMAP_MEM_FINALIZED;
1342 	}
1343 
1344 	for (i = 0; i < NETMAP_POOLS_NR; i++) {
1345 		nmd->lasterr = netmap_config_obj_allocator(&nmd->pools[i],
1346 				netmap_params[i].num, netmap_params[i].size);
1347 		if (nmd->lasterr)
1348 			goto out;
1349 	}
1350 
1351 out:
1352 
1353 	return nmd->lasterr;
1354 }
1355 
1356 static int
1357 netmap_mem_global_finalize(struct netmap_mem_d *nmd)
1358 {
1359 	int err;
1360 
1361 	/* update configuration if changed */
1362 	if (netmap_mem_global_config(nmd))
1363 		goto out;
1364 
1365 	nmd->active++;
1366 
1367 	if (nmd->flags & NETMAP_MEM_FINALIZED) {
1368 		/* may happen if config is not changed */
1369 		ND("nothing to do");
1370 		goto out;
1371 	}
1372 
1373 	if (netmap_mem_finalize_all(nmd))
1374 		goto out;
1375 
1376 	nmd->lasterr = 0;
1377 
1378 out:
1379 	if (nmd->lasterr)
1380 		nmd->active--;
1381 	err = nmd->lasterr;
1382 
1383 	return err;
1384 
1385 }
1386 
1387 static void
1388 netmap_mem_global_delete(struct netmap_mem_d *nmd)
1389 {
1390 	int i;
1391 
1392 	for (i = 0; i < NETMAP_POOLS_NR; i++) {
1393 	    netmap_destroy_obj_allocator(&nm_mem.pools[i]);
1394 	}
1395 
1396 	NMA_LOCK_DESTROY(&nm_mem);
1397 }
1398 
1399 int
1400 netmap_mem_init(void)
1401 {
1402 	NMA_LOCK_INIT(&nm_mem);
1403 	netmap_mem_get(&nm_mem);
1404 	return (0);
1405 }
1406 
1407 void
1408 netmap_mem_fini(void)
1409 {
1410 	netmap_mem_put(&nm_mem);
1411 }
1412 
1413 static void
1414 netmap_free_rings(struct netmap_adapter *na)
1415 {
1416 	enum txrx t;
1417 
1418 	for_rx_tx(t) {
1419 		u_int i;
1420 		for (i = 0; i < netmap_real_rings(na, t); i++) {
1421 			struct netmap_kring *kring = &NMR(na, t)[i];
1422 			struct netmap_ring *ring = kring->ring;
1423 
1424 			if (ring == NULL)
1425 				continue;
1426 			netmap_free_bufs(na->nm_mem, ring->slot, kring->nkr_num_slots);
1427 			netmap_ring_free(na->nm_mem, ring);
1428 			kring->ring = NULL;
1429 		}
1430 	}
1431 }
1432 
1433 /* call with NMA_LOCK held *
1434  *
1435  * Allocate netmap rings and buffers for this card
1436  * The rings are contiguous, but have variable size.
1437  * The kring array must follow the layout described
1438  * in netmap_krings_create().
1439  */
1440 static int
1441 netmap_mem2_rings_create(struct netmap_adapter *na)
1442 {
1443 	enum txrx t;
1444 
1445 	NMA_LOCK(na->nm_mem);
1446 
1447 	for_rx_tx(t) {
1448 		u_int i;
1449 
1450 		for (i = 0; i <= nma_get_nrings(na, t); i++) {
1451 			struct netmap_kring *kring = &NMR(na, t)[i];
1452 			struct netmap_ring *ring = kring->ring;
1453 			u_int len, ndesc;
1454 
1455 			if (ring) {
1456 				ND("%s already created", kring->name);
1457 				continue; /* already created by somebody else */
1458 			}
1459 			ndesc = kring->nkr_num_slots;
1460 			len = sizeof(struct netmap_ring) +
1461 				  ndesc * sizeof(struct netmap_slot);
1462 			ring = netmap_ring_malloc(na->nm_mem, len);
1463 			if (ring == NULL) {
1464 				D("Cannot allocate %s_ring", nm_txrx2str(t));
1465 				goto cleanup;
1466 			}
1467 			ND("txring at %p", ring);
1468 			kring->ring = ring;
1469 			*(uint32_t *)(uintptr_t)&ring->num_slots = ndesc;
1470 			*(int64_t *)(uintptr_t)&ring->buf_ofs =
1471 			    (na->nm_mem->pools[NETMAP_IF_POOL].memtotal +
1472 				na->nm_mem->pools[NETMAP_RING_POOL].memtotal) -
1473 				netmap_ring_offset(na->nm_mem, ring);
1474 
1475 			/* copy values from kring */
1476 			ring->head = kring->rhead;
1477 			ring->cur = kring->rcur;
1478 			ring->tail = kring->rtail;
1479 			*(uint16_t *)(uintptr_t)&ring->nr_buf_size =
1480 				netmap_mem_bufsize(na->nm_mem);
1481 			ND("%s h %d c %d t %d", kring->name,
1482 				ring->head, ring->cur, ring->tail);
1483 			ND("initializing slots for %s_ring", nm_txrx2str(txrx));
1484 			if (i != nma_get_nrings(na, t) || (na->na_flags & NAF_HOST_RINGS)) {
1485 				/* this is a real ring */
1486 				if (netmap_new_bufs(na->nm_mem, ring->slot, ndesc)) {
1487 					D("Cannot allocate buffers for %s_ring", nm_txrx2str(t));
1488 					goto cleanup;
1489 				}
1490 			} else {
1491 				/* this is a fake ring, set all indices to 0 */
1492 				netmap_mem_set_ring(na->nm_mem, ring->slot, ndesc, 0);
1493 			}
1494 		        /* ring info */
1495 		        *(uint16_t *)(uintptr_t)&ring->ringid = kring->ring_id;
1496 		        *(uint16_t *)(uintptr_t)&ring->dir = kring->tx;
1497 		}
1498 	}
1499 
1500 	NMA_UNLOCK(na->nm_mem);
1501 
1502 	return 0;
1503 
1504 cleanup:
1505 	netmap_free_rings(na);
1506 
1507 	NMA_UNLOCK(na->nm_mem);
1508 
1509 	return ENOMEM;
1510 }
1511 
1512 static void
1513 netmap_mem2_rings_delete(struct netmap_adapter *na)
1514 {
1515 	/* last instance, release bufs and rings */
1516 	NMA_LOCK(na->nm_mem);
1517 
1518 	netmap_free_rings(na);
1519 
1520 	NMA_UNLOCK(na->nm_mem);
1521 }
1522 
1523 
1524 /* call with NMA_LOCK held */
1525 /*
1526  * Allocate the per-fd structure netmap_if.
1527  *
1528  * We assume that the configuration stored in na
1529  * (number of tx/rx rings and descs) does not change while
1530  * the interface is in netmap mode.
1531  */
1532 static struct netmap_if *
1533 netmap_mem2_if_new(struct netmap_adapter *na)
1534 {
1535 	struct netmap_if *nifp;
1536 	ssize_t base; /* handy for relative offsets between rings and nifp */
1537 	u_int i, len, n[NR_TXRX], ntot;
1538 	enum txrx t;
1539 
1540 	ntot = 0;
1541 	for_rx_tx(t) {
1542 		/* account for the (eventually fake) host rings */
1543 		n[t] = nma_get_nrings(na, t) + 1;
1544 		ntot += n[t];
1545 	}
1546 	/*
1547 	 * the descriptor is followed inline by an array of offsets
1548 	 * to the tx and rx rings in the shared memory region.
1549 	 */
1550 
1551 	NMA_LOCK(na->nm_mem);
1552 
1553 	len = sizeof(struct netmap_if) + (ntot * sizeof(ssize_t));
1554 	nifp = netmap_if_malloc(na->nm_mem, len);
1555 	if (nifp == NULL) {
1556 		NMA_UNLOCK(na->nm_mem);
1557 		return NULL;
1558 	}
1559 
1560 	/* initialize base fields -- override const */
1561 	*(u_int *)(uintptr_t)&nifp->ni_tx_rings = na->num_tx_rings;
1562 	*(u_int *)(uintptr_t)&nifp->ni_rx_rings = na->num_rx_rings;
1563 	strncpy(nifp->ni_name, na->name, (size_t)IFNAMSIZ);
1564 
1565 	/*
1566 	 * fill the slots for the rx and tx rings. They contain the offset
1567 	 * between the ring and nifp, so the information is usable in
1568 	 * userspace to reach the ring from the nifp.
1569 	 */
1570 	base = netmap_if_offset(na->nm_mem, nifp);
1571 	for (i = 0; i < n[NR_TX]; i++) {
1572 		*(ssize_t *)(uintptr_t)&nifp->ring_ofs[i] =
1573 			netmap_ring_offset(na->nm_mem, na->tx_rings[i].ring) - base;
1574 	}
1575 	for (i = 0; i < n[NR_RX]; i++) {
1576 		*(ssize_t *)(uintptr_t)&nifp->ring_ofs[i+n[NR_TX]] =
1577 			netmap_ring_offset(na->nm_mem, na->rx_rings[i].ring) - base;
1578 	}
1579 
1580 	NMA_UNLOCK(na->nm_mem);
1581 
1582 	return (nifp);
1583 }
1584 
1585 static void
1586 netmap_mem2_if_delete(struct netmap_adapter *na, struct netmap_if *nifp)
1587 {
1588 	if (nifp == NULL)
1589 		/* nothing to do */
1590 		return;
1591 	NMA_LOCK(na->nm_mem);
1592 	if (nifp->ni_bufs_head)
1593 		netmap_extra_free(na, nifp->ni_bufs_head);
1594 	netmap_if_free(na->nm_mem, nifp);
1595 
1596 	NMA_UNLOCK(na->nm_mem);
1597 }
1598 
1599 static void
1600 netmap_mem_global_deref(struct netmap_mem_d *nmd)
1601 {
1602 
1603 	nmd->active--;
1604 	if (!nmd->active)
1605 		nmd->nm_grp = -1;
1606 	if (netmap_verbose)
1607 		D("active = %d", nmd->active);
1608 
1609 }
1610 
1611 struct netmap_mem_ops netmap_mem_global_ops = {
1612 	.nmd_get_lut = netmap_mem2_get_lut,
1613 	.nmd_get_info = netmap_mem2_get_info,
1614 	.nmd_ofstophys = netmap_mem2_ofstophys,
1615 	.nmd_config = netmap_mem_global_config,
1616 	.nmd_finalize = netmap_mem_global_finalize,
1617 	.nmd_deref = netmap_mem_global_deref,
1618 	.nmd_delete = netmap_mem_global_delete,
1619 	.nmd_if_offset = netmap_mem2_if_offset,
1620 	.nmd_if_new = netmap_mem2_if_new,
1621 	.nmd_if_delete = netmap_mem2_if_delete,
1622 	.nmd_rings_create = netmap_mem2_rings_create,
1623 	.nmd_rings_delete = netmap_mem2_rings_delete
1624 };
1625 struct netmap_mem_ops netmap_mem_private_ops = {
1626 	.nmd_get_lut = netmap_mem2_get_lut,
1627 	.nmd_get_info = netmap_mem2_get_info,
1628 	.nmd_ofstophys = netmap_mem2_ofstophys,
1629 	.nmd_config = netmap_mem_private_config,
1630 	.nmd_finalize = netmap_mem_private_finalize,
1631 	.nmd_deref = netmap_mem_private_deref,
1632 	.nmd_if_offset = netmap_mem2_if_offset,
1633 	.nmd_delete = netmap_mem_private_delete,
1634 	.nmd_if_new = netmap_mem2_if_new,
1635 	.nmd_if_delete = netmap_mem2_if_delete,
1636 	.nmd_rings_create = netmap_mem2_rings_create,
1637 	.nmd_rings_delete = netmap_mem2_rings_delete
1638 };
1639