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