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 if (mtx_initialized(&contigmem_buffers[i].mtx)) 172 mtx_destroy(&contigmem_buffers[i].mtx); 173 } 174 175 return error; 176 } 177 178 static int 179 contigmem_unload() 180 { 181 int i; 182 183 if (contigmem_refcnt > 0) 184 return EBUSY; 185 186 if (contigmem_cdev != NULL) 187 destroy_dev(contigmem_cdev); 188 189 if (contigmem_eh_tag != NULL) 190 EVENTHANDLER_DEREGISTER(process_exit, contigmem_eh_tag); 191 192 for (i = 0; i < RTE_CONTIGMEM_MAX_NUM_BUFS; i++) { 193 if (contigmem_buffers[i].addr != NULL) 194 contigfree(contigmem_buffers[i].addr, 195 contigmem_buffer_size, M_CONTIGMEM); 196 if (mtx_initialized(&contigmem_buffers[i].mtx)) 197 mtx_destroy(&contigmem_buffers[i].mtx); 198 } 199 200 return 0; 201 } 202 203 static int 204 contigmem_physaddr(SYSCTL_HANDLER_ARGS) 205 { 206 uint64_t physaddr; 207 int index = (int)(uintptr_t)arg1; 208 209 physaddr = (uint64_t)vtophys(contigmem_buffers[index].addr); 210 return sysctl_handle_64(oidp, &physaddr, 0, req); 211 } 212 213 static int 214 contigmem_open(struct cdev *cdev, int fflags, int devtype, 215 struct thread *td) 216 { 217 218 atomic_add_int(&contigmem_refcnt, 1); 219 220 return 0; 221 } 222 223 static int 224 contigmem_close(struct cdev *cdev, int fflags, int devtype, 225 struct thread *td) 226 { 227 228 atomic_subtract_int(&contigmem_refcnt, 1); 229 230 return 0; 231 } 232 233 static int 234 contigmem_cdev_pager_ctor(void *handle, vm_ooffset_t size, vm_prot_t prot, 235 vm_ooffset_t foff, struct ucred *cred, u_short *color) 236 { 237 struct contigmem_vm_handle *vmh = handle; 238 struct contigmem_buffer *buf; 239 240 buf = &contigmem_buffers[vmh->buffer_index]; 241 242 atomic_add_int(&contigmem_refcnt, 1); 243 244 mtx_lock(&buf->mtx); 245 if (buf->refcnt == 0) 246 memset(buf->addr, 0, contigmem_buffer_size); 247 buf->refcnt++; 248 mtx_unlock(&buf->mtx); 249 250 return 0; 251 } 252 253 static void 254 contigmem_cdev_pager_dtor(void *handle) 255 { 256 struct contigmem_vm_handle *vmh = handle; 257 struct contigmem_buffer *buf; 258 259 buf = &contigmem_buffers[vmh->buffer_index]; 260 261 mtx_lock(&buf->mtx); 262 buf->refcnt--; 263 mtx_unlock(&buf->mtx); 264 265 free(vmh, M_CONTIGMEM); 266 267 atomic_subtract_int(&contigmem_refcnt, 1); 268 } 269 270 static int 271 contigmem_cdev_pager_fault(vm_object_t object, vm_ooffset_t offset, int prot, 272 vm_page_t *mres) 273 { 274 vm_paddr_t paddr; 275 vm_page_t m_paddr, page; 276 vm_memattr_t memattr, memattr1; 277 278 memattr = object->memattr; 279 280 VM_OBJECT_WUNLOCK(object); 281 282 paddr = offset; 283 284 m_paddr = vm_phys_paddr_to_vm_page(paddr); 285 if (m_paddr != NULL) { 286 memattr1 = pmap_page_get_memattr(m_paddr); 287 if (memattr1 != memattr) 288 memattr = memattr1; 289 } 290 291 if (((*mres)->flags & PG_FICTITIOUS) != 0) { 292 /* 293 * If the passed in result page is a fake page, update it with 294 * the new physical address. 295 */ 296 page = *mres; 297 VM_OBJECT_WLOCK(object); 298 vm_page_updatefake(page, paddr, memattr); 299 } else { 300 vm_page_t mret; 301 /* 302 * Replace the passed in reqpage page with our own fake page and 303 * free up the original page. 304 */ 305 page = vm_page_getfake(paddr, memattr); 306 VM_OBJECT_WLOCK(object); 307 mret = vm_page_replace(page, object, (*mres)->pindex); 308 KASSERT(mret == *mres, 309 ("invalid page replacement, old=%p, ret=%p", *mres, mret)); 310 vm_page_lock(mret); 311 vm_page_free(mret); 312 vm_page_unlock(mret); 313 *mres = page; 314 } 315 316 page->valid = VM_PAGE_BITS_ALL; 317 318 return VM_PAGER_OK; 319 } 320 321 static struct cdev_pager_ops contigmem_cdev_pager_ops = { 322 .cdev_pg_ctor = contigmem_cdev_pager_ctor, 323 .cdev_pg_dtor = contigmem_cdev_pager_dtor, 324 .cdev_pg_fault = contigmem_cdev_pager_fault, 325 }; 326 327 static int 328 contigmem_mmap_single(struct cdev *cdev, vm_ooffset_t *offset, vm_size_t size, 329 struct vm_object **obj, int nprot) 330 { 331 struct contigmem_vm_handle *vmh; 332 uint64_t buffer_index; 333 334 /* 335 * The buffer index is encoded in the offset. Divide the offset by 336 * PAGE_SIZE to get the index of the buffer requested by the user 337 * app. 338 */ 339 buffer_index = *offset / PAGE_SIZE; 340 if (buffer_index >= contigmem_num_buffers) 341 return EINVAL; 342 343 if (size > contigmem_buffer_size) 344 return EINVAL; 345 346 vmh = malloc(sizeof(*vmh), M_CONTIGMEM, M_NOWAIT | M_ZERO); 347 if (vmh == NULL) 348 return ENOMEM; 349 vmh->buffer_index = buffer_index; 350 351 *offset = (vm_ooffset_t)vtophys(contigmem_buffers[buffer_index].addr); 352 *obj = cdev_pager_allocate(vmh, OBJT_DEVICE, &contigmem_cdev_pager_ops, 353 size, nprot, *offset, curthread->td_ucred); 354 355 return 0; 356 } 357