1 /* SPDX-License-Identifier: BSD-3-Clause 2 * Copyright(c) 2010-2014 Intel Corporation 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 34 struct contigmem_buffer { 35 void *addr; 36 int refcnt; 37 struct mtx mtx; 38 }; 39 40 struct contigmem_vm_handle { 41 int buffer_index; 42 }; 43 44 static int contigmem_load(void); 45 static int contigmem_unload(void); 46 static int contigmem_physaddr(SYSCTL_HANDLER_ARGS); 47 48 static d_mmap_single_t contigmem_mmap_single; 49 static d_open_t contigmem_open; 50 static d_close_t contigmem_close; 51 52 static int contigmem_num_buffers = RTE_CONTIGMEM_DEFAULT_NUM_BUFS; 53 static int64_t contigmem_buffer_size = RTE_CONTIGMEM_DEFAULT_BUF_SIZE; 54 55 static eventhandler_tag contigmem_eh_tag; 56 static struct contigmem_buffer contigmem_buffers[RTE_CONTIGMEM_MAX_NUM_BUFS]; 57 static struct cdev *contigmem_cdev = NULL; 58 static int contigmem_refcnt; 59 60 TUNABLE_INT("hw.contigmem.num_buffers", &contigmem_num_buffers); 61 TUNABLE_QUAD("hw.contigmem.buffer_size", &contigmem_buffer_size); 62 63 static SYSCTL_NODE(_hw, OID_AUTO, contigmem, CTLFLAG_RD, 0, "contigmem"); 64 65 SYSCTL_INT(_hw_contigmem, OID_AUTO, num_buffers, CTLFLAG_RD, 66 &contigmem_num_buffers, 0, "Number of contigmem buffers allocated"); 67 SYSCTL_QUAD(_hw_contigmem, OID_AUTO, buffer_size, CTLFLAG_RD, 68 &contigmem_buffer_size, 0, "Size of each contiguous buffer"); 69 SYSCTL_INT(_hw_contigmem, OID_AUTO, num_references, CTLFLAG_RD, 70 &contigmem_refcnt, 0, "Number of references to contigmem"); 71 72 static SYSCTL_NODE(_hw_contigmem, OID_AUTO, physaddr, CTLFLAG_RD, 0, 73 "physaddr"); 74 75 MALLOC_DEFINE(M_CONTIGMEM, "contigmem", "contigmem(4) allocations"); 76 77 static 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 95 moduledata_t contigmem_mod = { 96 "contigmem", 97 (modeventhand_t)contigmem_modevent, 98 0 99 }; 100 101 DECLARE_MODULE(contigmem, contigmem_mod, SI_SUB_DRIVERS, SI_ORDER_ANY); 102 MODULE_VERSION(contigmem, 1); 103 104 static 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 }; 112 113 static int 114 contigmem_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; 165 166 error: 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 } 179 180 static int 181 contigmem_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 } 204 205 static int 206 contigmem_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 } 214 215 static int 216 contigmem_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 } 224 225 static int 226 contigmem_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 } 234 235 static int 236 contigmem_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 } 254 255 static void 256 contigmem_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 } 271 272 static int 273 contigmem_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 * If the passed in result page is a fake page, update it with 296 * the new physical address. 297 */ 298 page = *mres; 299 VM_OBJECT_WLOCK(object); 300 vm_page_updatefake(page, paddr, memattr); 301 } else { 302 /* 303 * Replace the passed in reqpage page with our own fake page and 304 * free up the original page. 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 } 325 326 static 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 }; 331 332 static int 333 contigmem_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 * The buffer index is encoded in the offset. Divide the offset by 341 * PAGE_SIZE to get the index of the buffer requested by the user 342 * app. 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