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 static bool contigmem_coredump_enable; 55 56 static eventhandler_tag contigmem_eh_tag; 57 static struct contigmem_buffer contigmem_buffers[RTE_CONTIGMEM_MAX_NUM_BUFS]; 58 static struct cdev *contigmem_cdev = NULL; 59 static int contigmem_refcnt; 60 61 TUNABLE_INT("hw.contigmem.num_buffers", &contigmem_num_buffers); 62 TUNABLE_QUAD("hw.contigmem.buffer_size", &contigmem_buffer_size); 63 TUNABLE_BOOL("hw.contigmem.coredump_enable", &contigmem_coredump_enable); 64 65 static SYSCTL_NODE(_hw, OID_AUTO, contigmem, CTLFLAG_RD, 0, "contigmem"); 66 67 SYSCTL_INT(_hw_contigmem, OID_AUTO, num_buffers, CTLFLAG_RD, 68 &contigmem_num_buffers, 0, "Number of contigmem buffers allocated"); 69 SYSCTL_QUAD(_hw_contigmem, OID_AUTO, buffer_size, CTLFLAG_RD, 70 &contigmem_buffer_size, 0, "Size of each contiguous buffer"); 71 SYSCTL_INT(_hw_contigmem, OID_AUTO, num_references, CTLFLAG_RD, 72 &contigmem_refcnt, 0, "Number of references to contigmem"); 73 SYSCTL_BOOL(_hw_contigmem, OID_AUTO, coredump_enable, CTLFLAG_RD, 74 &contigmem_coredump_enable, 0, "Include mapped buffers in core dump"); 75 76 static SYSCTL_NODE(_hw_contigmem, OID_AUTO, physaddr, CTLFLAG_RD, 0, 77 "physaddr"); 78 79 MALLOC_DEFINE(M_CONTIGMEM, "contigmem", "contigmem(4) allocations"); 80 81 static int contigmem_modevent(module_t mod, int type, void *arg) 82 { 83 int error = 0; 84 85 switch (type) { 86 case MOD_LOAD: 87 error = contigmem_load(); 88 break; 89 case MOD_UNLOAD: 90 error = contigmem_unload(); 91 break; 92 default: 93 break; 94 } 95 96 return error; 97 } 98 99 moduledata_t contigmem_mod = { 100 "contigmem", 101 (modeventhand_t)contigmem_modevent, 102 0 103 }; 104 105 DECLARE_MODULE(contigmem, contigmem_mod, SI_SUB_DRIVERS, SI_ORDER_ANY); 106 MODULE_VERSION(contigmem, 1); 107 108 static struct cdevsw contigmem_ops = { 109 .d_name = "contigmem", 110 .d_version = D_VERSION, 111 .d_flags = D_TRACKCLOSE, 112 .d_mmap_single = contigmem_mmap_single, 113 .d_open = contigmem_open, 114 .d_close = contigmem_close, 115 }; 116 117 static int 118 contigmem_load(void) 119 { 120 char index_string[8], description[32]; 121 int i, error = 0; 122 void *addr; 123 124 if (contigmem_num_buffers > RTE_CONTIGMEM_MAX_NUM_BUFS) { 125 printf("%d buffers requested is greater than %d allowed\n", 126 contigmem_num_buffers, RTE_CONTIGMEM_MAX_NUM_BUFS); 127 error = EINVAL; 128 goto error; 129 } 130 131 if (contigmem_buffer_size < PAGE_SIZE || 132 (contigmem_buffer_size & (contigmem_buffer_size - 1)) != 0) { 133 printf("buffer size 0x%lx is not greater than PAGE_SIZE and " 134 "power of two\n", contigmem_buffer_size); 135 error = EINVAL; 136 goto error; 137 } 138 139 for (i = 0; i < contigmem_num_buffers; i++) { 140 addr = contigmalloc(contigmem_buffer_size, M_CONTIGMEM, M_ZERO, 141 0, BUS_SPACE_MAXADDR, contigmem_buffer_size, 0); 142 if (addr == NULL) { 143 printf("contigmalloc failed for buffer %d\n", i); 144 error = ENOMEM; 145 goto error; 146 } 147 148 printf("%2u: virt=%p phys=%p\n", i, addr, 149 (void *)pmap_kextract((vm_offset_t)addr)); 150 151 mtx_init(&contigmem_buffers[i].mtx, "contigmem", NULL, MTX_DEF); 152 contigmem_buffers[i].addr = addr; 153 contigmem_buffers[i].refcnt = 0; 154 155 snprintf(index_string, sizeof(index_string), "%d", i); 156 snprintf(description, sizeof(description), 157 "phys addr for buffer %d", i); 158 SYSCTL_ADD_PROC(NULL, 159 &SYSCTL_NODE_CHILDREN(_hw_contigmem, physaddr), OID_AUTO, 160 index_string, CTLTYPE_U64 | CTLFLAG_RD, 161 (void *)(uintptr_t)i, 0, contigmem_physaddr, "LU", 162 description); 163 } 164 165 contigmem_cdev = make_dev_credf(0, &contigmem_ops, 0, NULL, UID_ROOT, 166 GID_WHEEL, 0600, "contigmem"); 167 168 return 0; 169 170 error: 171 for (i = 0; i < contigmem_num_buffers; i++) { 172 if (contigmem_buffers[i].addr != NULL) { 173 contigfree(contigmem_buffers[i].addr, 174 contigmem_buffer_size, M_CONTIGMEM); 175 contigmem_buffers[i].addr = NULL; 176 } 177 if (mtx_initialized(&contigmem_buffers[i].mtx)) 178 mtx_destroy(&contigmem_buffers[i].mtx); 179 } 180 181 return error; 182 } 183 184 static int 185 contigmem_unload(void) 186 { 187 int i; 188 189 if (contigmem_refcnt > 0) 190 return EBUSY; 191 192 if (contigmem_cdev != NULL) 193 destroy_dev(contigmem_cdev); 194 195 if (contigmem_eh_tag != NULL) 196 EVENTHANDLER_DEREGISTER(process_exit, contigmem_eh_tag); 197 198 for (i = 0; i < RTE_CONTIGMEM_MAX_NUM_BUFS; i++) { 199 if (contigmem_buffers[i].addr != NULL) 200 contigfree(contigmem_buffers[i].addr, 201 contigmem_buffer_size, M_CONTIGMEM); 202 if (mtx_initialized(&contigmem_buffers[i].mtx)) 203 mtx_destroy(&contigmem_buffers[i].mtx); 204 } 205 206 return 0; 207 } 208 209 static int 210 contigmem_physaddr(SYSCTL_HANDLER_ARGS) 211 { 212 uint64_t physaddr; 213 int index = (int)(uintptr_t)arg1; 214 215 physaddr = (uint64_t)vtophys(contigmem_buffers[index].addr); 216 return sysctl_handle_64(oidp, &physaddr, 0, req); 217 } 218 219 static int 220 contigmem_open(struct cdev *cdev, int fflags, int devtype, 221 struct thread *td) 222 { 223 224 atomic_add_int(&contigmem_refcnt, 1); 225 226 return 0; 227 } 228 229 static int 230 contigmem_close(struct cdev *cdev, int fflags, int devtype, 231 struct thread *td) 232 { 233 234 atomic_subtract_int(&contigmem_refcnt, 1); 235 236 return 0; 237 } 238 239 static int 240 contigmem_cdev_pager_ctor(void *handle, vm_ooffset_t size, vm_prot_t prot, 241 vm_ooffset_t foff, struct ucred *cred, u_short *color) 242 { 243 struct contigmem_vm_handle *vmh = handle; 244 struct contigmem_buffer *buf; 245 246 buf = &contigmem_buffers[vmh->buffer_index]; 247 248 atomic_add_int(&contigmem_refcnt, 1); 249 250 mtx_lock(&buf->mtx); 251 if (buf->refcnt == 0) 252 memset(buf->addr, 0, contigmem_buffer_size); 253 buf->refcnt++; 254 mtx_unlock(&buf->mtx); 255 256 return 0; 257 } 258 259 static void 260 contigmem_cdev_pager_dtor(void *handle) 261 { 262 struct contigmem_vm_handle *vmh = handle; 263 struct contigmem_buffer *buf; 264 265 buf = &contigmem_buffers[vmh->buffer_index]; 266 267 mtx_lock(&buf->mtx); 268 buf->refcnt--; 269 mtx_unlock(&buf->mtx); 270 271 free(vmh, M_CONTIGMEM); 272 273 atomic_subtract_int(&contigmem_refcnt, 1); 274 } 275 276 static int 277 contigmem_cdev_pager_fault(vm_object_t object, vm_ooffset_t offset, int prot, 278 vm_page_t *mres) 279 { 280 vm_paddr_t paddr; 281 vm_page_t m_paddr, page; 282 vm_memattr_t memattr, memattr1; 283 284 memattr = object->memattr; 285 286 VM_OBJECT_WUNLOCK(object); 287 288 paddr = offset; 289 290 m_paddr = vm_phys_paddr_to_vm_page(paddr); 291 if (m_paddr != NULL) { 292 memattr1 = pmap_page_get_memattr(m_paddr); 293 if (memattr1 != memattr) 294 memattr = memattr1; 295 } 296 297 if (((*mres)->flags & PG_FICTITIOUS) != 0) { 298 /* 299 * If the passed in result page is a fake page, update it with 300 * the new physical address. 301 */ 302 page = *mres; 303 VM_OBJECT_WLOCK(object); 304 vm_page_updatefake(page, paddr, memattr); 305 } else { 306 /* 307 * Replace the passed in reqpage page with our own fake page and 308 * free up the original page. 309 */ 310 page = vm_page_getfake(paddr, memattr); 311 VM_OBJECT_WLOCK(object); 312 #if __FreeBSD__ >= 13 313 vm_page_replace(page, object, (*mres)->pindex, *mres); 314 #else 315 vm_page_t mret = vm_page_replace(page, object, (*mres)->pindex); 316 KASSERT(mret == *mres, 317 ("invalid page replacement, old=%p, ret=%p", *mres, mret)); 318 vm_page_lock(mret); 319 vm_page_free(mret); 320 vm_page_unlock(mret); 321 #endif 322 *mres = page; 323 } 324 325 page->valid = VM_PAGE_BITS_ALL; 326 327 return VM_PAGER_OK; 328 } 329 330 static struct cdev_pager_ops contigmem_cdev_pager_ops = { 331 .cdev_pg_ctor = contigmem_cdev_pager_ctor, 332 .cdev_pg_dtor = contigmem_cdev_pager_dtor, 333 .cdev_pg_fault = contigmem_cdev_pager_fault, 334 }; 335 336 static int 337 contigmem_mmap_single(struct cdev *cdev, vm_ooffset_t *offset, vm_size_t size, 338 struct vm_object **obj, int nprot) 339 { 340 struct contigmem_vm_handle *vmh; 341 uint64_t buffer_index; 342 343 /* 344 * The buffer index is encoded in the offset. Divide the offset by 345 * PAGE_SIZE to get the index of the buffer requested by the user 346 * app. 347 */ 348 buffer_index = *offset / PAGE_SIZE; 349 if (buffer_index >= contigmem_num_buffers) 350 return EINVAL; 351 352 if (size > contigmem_buffer_size) 353 return EINVAL; 354 355 vmh = malloc(sizeof(*vmh), M_CONTIGMEM, M_NOWAIT | M_ZERO); 356 if (vmh == NULL) 357 return ENOMEM; 358 vmh->buffer_index = buffer_index; 359 360 *offset = (vm_ooffset_t)vtophys(contigmem_buffers[buffer_index].addr); 361 *obj = cdev_pager_allocate(vmh, OBJT_DEVICE, &contigmem_cdev_pager_ops, 362 size, nprot, *offset, curthread->td_ucred); 363 364 /* Mappings backed by OBJ_FICTITIOUS are excluded from core dump. */ 365 if (contigmem_coredump_enable) 366 (*obj)->flags &= ~OBJ_FICTITIOUS; 367 368 return 0; 369 } 370