1
2
3
4
5#include <sys/cdefs.h>
6__FBSDID("$FreeBSD$");
7
8#include <sys/param.h>
9#include <sys/bio.h>
10#include <sys/bus.h>
11#include <sys/conf.h>
12#include <sys/kernel.h>
13#include <sys/malloc.h>
14#include <sys/module.h>
15#include <sys/proc.h>
16#include <sys/lock.h>
17#include <sys/rwlock.h>
18#include <sys/mutex.h>
19#include <sys/systm.h>
20#include <sys/sysctl.h>
21#include <sys/vmmeter.h>
22#include <sys/eventhandler.h>
23
24#include <machine/bus.h>
25
26#include <vm/vm.h>
27#include <vm/pmap.h>
28#include <vm/vm_param.h>
29#include <vm/vm_object.h>
30#include <vm/vm_page.h>
31#include <vm/vm_pager.h>
32#include <vm/vm_phys.h>
33
34struct contigmem_buffer {
35 void *addr;
36 int refcnt;
37 struct mtx mtx;
38};
39
40struct contigmem_vm_handle {
41 int buffer_index;
42};
43
44static int contigmem_load(void);
45static int contigmem_unload(void);
46static int contigmem_physaddr(SYSCTL_HANDLER_ARGS);
47
48static d_mmap_single_t contigmem_mmap_single;
49static d_open_t contigmem_open;
50static d_close_t contigmem_close;
51
52static int contigmem_num_buffers = RTE_CONTIGMEM_DEFAULT_NUM_BUFS;
53static int64_t contigmem_buffer_size = RTE_CONTIGMEM_DEFAULT_BUF_SIZE;
54
55static eventhandler_tag contigmem_eh_tag;
56static struct contigmem_buffer contigmem_buffers[RTE_CONTIGMEM_MAX_NUM_BUFS];
57static struct cdev *contigmem_cdev = NULL;
58static int contigmem_refcnt;
59
60TUNABLE_INT("hw.contigmem.num_buffers", &contigmem_num_buffers);
61TUNABLE_QUAD("hw.contigmem.buffer_size", &contigmem_buffer_size);
62
63static SYSCTL_NODE(_hw, OID_AUTO, contigmem, CTLFLAG_RD, 0, "contigmem");
64
65SYSCTL_INT(_hw_contigmem, OID_AUTO, num_buffers, CTLFLAG_RD,
66 &contigmem_num_buffers, 0, "Number of contigmem buffers allocated");
67SYSCTL_QUAD(_hw_contigmem, OID_AUTO, buffer_size, CTLFLAG_RD,
68 &contigmem_buffer_size, 0, "Size of each contiguous buffer");
69SYSCTL_INT(_hw_contigmem, OID_AUTO, num_references, CTLFLAG_RD,
70 &contigmem_refcnt, 0, "Number of references to contigmem");
71
72static SYSCTL_NODE(_hw_contigmem, OID_AUTO, physaddr, CTLFLAG_RD, 0,
73 "physaddr");
74
75MALLOC_DEFINE(M_CONTIGMEM, "contigmem", "contigmem(4) allocations");
76
77static int contigmem_modevent(module_t mod, int type, void *arg)
78{
79 int error = 0;
80
81 switch (type) {
82 case MOD_LOAD:
83 error = contigmem_load();
84 break;
85 case MOD_UNLOAD:
86 error = contigmem_unload();
87 break;
88 default:
89 break;
90 }
91
92 return error;
93}
94
95moduledata_t contigmem_mod = {
96 "contigmem",
97 (modeventhand_t)contigmem_modevent,
98 0
99};
100
101DECLARE_MODULE(contigmem, contigmem_mod, SI_SUB_DRIVERS, SI_ORDER_ANY);
102MODULE_VERSION(contigmem, 1);
103
104static struct cdevsw contigmem_ops = {
105 .d_name = "contigmem",
106 .d_version = D_VERSION,
107 .d_flags = D_TRACKCLOSE,
108 .d_mmap_single = contigmem_mmap_single,
109 .d_open = contigmem_open,
110 .d_close = contigmem_close,
111};
112
113static int
114contigmem_load()
115{
116 char index_string[8], description[32];
117 int i, error = 0;
118 void *addr;
119
120 if (contigmem_num_buffers > RTE_CONTIGMEM_MAX_NUM_BUFS) {
121 printf("%d buffers requested is greater than %d allowed\n",
122 contigmem_num_buffers, RTE_CONTIGMEM_MAX_NUM_BUFS);
123 error = EINVAL;
124 goto error;
125 }
126
127 if (contigmem_buffer_size < PAGE_SIZE ||
128 (contigmem_buffer_size & (contigmem_buffer_size - 1)) != 0) {
129 printf("buffer size 0x%lx is not greater than PAGE_SIZE and "
130 "power of two\n", contigmem_buffer_size);
131 error = EINVAL;
132 goto error;
133 }
134
135 for (i = 0; i < contigmem_num_buffers; i++) {
136 addr = contigmalloc(contigmem_buffer_size, M_CONTIGMEM, M_ZERO,
137 0, BUS_SPACE_MAXADDR, contigmem_buffer_size, 0);
138 if (addr == NULL) {
139 printf("contigmalloc failed for buffer %d\n", i);
140 error = ENOMEM;
141 goto error;
142 }
143
144 printf("%2u: virt=%p phys=%p\n", i, addr,
145 (void *)pmap_kextract((vm_offset_t)addr));
146
147 mtx_init(&contigmem_buffers[i].mtx, "contigmem", NULL, MTX_DEF);
148 contigmem_buffers[i].addr = addr;
149 contigmem_buffers[i].refcnt = 0;
150
151 snprintf(index_string, sizeof(index_string), "%d", i);
152 snprintf(description, sizeof(description),
153 "phys addr for buffer %d", i);
154 SYSCTL_ADD_PROC(NULL,
155 &SYSCTL_NODE_CHILDREN(_hw_contigmem, physaddr), OID_AUTO,
156 index_string, CTLTYPE_U64 | CTLFLAG_RD,
157 (void *)(uintptr_t)i, 0, contigmem_physaddr, "LU",
158 description);
159 }
160
161 contigmem_cdev = make_dev_credf(0, &contigmem_ops, 0, NULL, UID_ROOT,
162 GID_WHEEL, 0600, "contigmem");
163
164 return 0;
165
166error:
167 for (i = 0; i < contigmem_num_buffers; i++) {
168 if (contigmem_buffers[i].addr != NULL) {
169 contigfree(contigmem_buffers[i].addr,
170 contigmem_buffer_size, M_CONTIGMEM);
171 contigmem_buffers[i].addr = NULL;
172 }
173 if (mtx_initialized(&contigmem_buffers[i].mtx))
174 mtx_destroy(&contigmem_buffers[i].mtx);
175 }
176
177 return error;
178}
179
180static int
181contigmem_unload()
182{
183 int i;
184
185 if (contigmem_refcnt > 0)
186 return EBUSY;
187
188 if (contigmem_cdev != NULL)
189 destroy_dev(contigmem_cdev);
190
191 if (contigmem_eh_tag != NULL)
192 EVENTHANDLER_DEREGISTER(process_exit, contigmem_eh_tag);
193
194 for (i = 0; i < RTE_CONTIGMEM_MAX_NUM_BUFS; i++) {
195 if (contigmem_buffers[i].addr != NULL)
196 contigfree(contigmem_buffers[i].addr,
197 contigmem_buffer_size, M_CONTIGMEM);
198 if (mtx_initialized(&contigmem_buffers[i].mtx))
199 mtx_destroy(&contigmem_buffers[i].mtx);
200 }
201
202 return 0;
203}
204
205static int
206contigmem_physaddr(SYSCTL_HANDLER_ARGS)
207{
208 uint64_t physaddr;
209 int index = (int)(uintptr_t)arg1;
210
211 physaddr = (uint64_t)vtophys(contigmem_buffers[index].addr);
212 return sysctl_handle_64(oidp, &physaddr, 0, req);
213}
214
215static int
216contigmem_open(struct cdev *cdev, int fflags, int devtype,
217 struct thread *td)
218{
219
220 atomic_add_int(&contigmem_refcnt, 1);
221
222 return 0;
223}
224
225static int
226contigmem_close(struct cdev *cdev, int fflags, int devtype,
227 struct thread *td)
228{
229
230 atomic_subtract_int(&contigmem_refcnt, 1);
231
232 return 0;
233}
234
235static int
236contigmem_cdev_pager_ctor(void *handle, vm_ooffset_t size, vm_prot_t prot,
237 vm_ooffset_t foff, struct ucred *cred, u_short *color)
238{
239 struct contigmem_vm_handle *vmh = handle;
240 struct contigmem_buffer *buf;
241
242 buf = &contigmem_buffers[vmh->buffer_index];
243
244 atomic_add_int(&contigmem_refcnt, 1);
245
246 mtx_lock(&buf->mtx);
247 if (buf->refcnt == 0)
248 memset(buf->addr, 0, contigmem_buffer_size);
249 buf->refcnt++;
250 mtx_unlock(&buf->mtx);
251
252 return 0;
253}
254
255static void
256contigmem_cdev_pager_dtor(void *handle)
257{
258 struct contigmem_vm_handle *vmh = handle;
259 struct contigmem_buffer *buf;
260
261 buf = &contigmem_buffers[vmh->buffer_index];
262
263 mtx_lock(&buf->mtx);
264 buf->refcnt--;
265 mtx_unlock(&buf->mtx);
266
267 free(vmh, M_CONTIGMEM);
268
269 atomic_subtract_int(&contigmem_refcnt, 1);
270}
271
272static int
273contigmem_cdev_pager_fault(vm_object_t object, vm_ooffset_t offset, int prot,
274 vm_page_t *mres)
275{
276 vm_paddr_t paddr;
277 vm_page_t m_paddr, page;
278 vm_memattr_t memattr, memattr1;
279
280 memattr = object->memattr;
281
282 VM_OBJECT_WUNLOCK(object);
283
284 paddr = offset;
285
286 m_paddr = vm_phys_paddr_to_vm_page(paddr);
287 if (m_paddr != NULL) {
288 memattr1 = pmap_page_get_memattr(m_paddr);
289 if (memattr1 != memattr)
290 memattr = memattr1;
291 }
292
293 if (((*mres)->flags & PG_FICTITIOUS) != 0) {
294
295
296
297
298 page = *mres;
299 VM_OBJECT_WLOCK(object);
300 vm_page_updatefake(page, paddr, memattr);
301 } else {
302
303
304
305
306 page = vm_page_getfake(paddr, memattr);
307 VM_OBJECT_WLOCK(object);
308#if __FreeBSD__ >= 13
309 vm_page_replace(page, object, (*mres)->pindex, *mres);
310#else
311 vm_page_t mret = vm_page_replace(page, object, (*mres)->pindex);
312 KASSERT(mret == *mres,
313 ("invalid page replacement, old=%p, ret=%p", *mres, mret));
314 vm_page_lock(mret);
315 vm_page_free(mret);
316 vm_page_unlock(mret);
317#endif
318 *mres = page;
319 }
320
321 page->valid = VM_PAGE_BITS_ALL;
322
323 return VM_PAGER_OK;
324}
325
326static struct cdev_pager_ops contigmem_cdev_pager_ops = {
327 .cdev_pg_ctor = contigmem_cdev_pager_ctor,
328 .cdev_pg_dtor = contigmem_cdev_pager_dtor,
329 .cdev_pg_fault = contigmem_cdev_pager_fault,
330};
331
332static int
333contigmem_mmap_single(struct cdev *cdev, vm_ooffset_t *offset, vm_size_t size,
334 struct vm_object **obj, int nprot)
335{
336 struct contigmem_vm_handle *vmh;
337 uint64_t buffer_index;
338
339
340
341
342
343
344 buffer_index = *offset / PAGE_SIZE;
345 if (buffer_index >= contigmem_num_buffers)
346 return EINVAL;
347
348 if (size > contigmem_buffer_size)
349 return EINVAL;
350
351 vmh = malloc(sizeof(*vmh), M_CONTIGMEM, M_NOWAIT | M_ZERO);
352 if (vmh == NULL)
353 return ENOMEM;
354 vmh->buffer_index = buffer_index;
355
356 *offset = (vm_ooffset_t)vtophys(contigmem_buffers[buffer_index].addr);
357 *obj = cdev_pager_allocate(vmh, OBJT_DEVICE, &contigmem_cdev_pager_ops,
358 size, nprot, *offset, curthread->td_ucred);
359
360 return 0;
361}
362
