1 /*- 2 * Copyright (c) 1990 University of Utah. 3 * Copyright (c) 1991, 1993 4 * The Regents of the University of California. All rights reserved. 5 * 6 * This code is derived from software contributed to Berkeley by 7 * the Systems Programming Group of the University of Utah Computer 8 * Science Department. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 4. Neither the name of the University nor the names of its contributors 19 * may be used to endorse or promote products derived from this software 20 * without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 * 34 * @(#)device_pager.c 8.1 (Berkeley) 6/11/93 35 */ 36 37 #include <sys/cdefs.h> 38 __FBSDID("$FreeBSD$"); 39 40 #include <sys/param.h> 41 #include <sys/systm.h> 42 #include <sys/conf.h> 43 #include <sys/lock.h> 44 #include <sys/proc.h> 45 #include <sys/mutex.h> 46 #include <sys/mman.h> 47 #include <sys/rwlock.h> 48 #include <sys/sx.h> 49 50 #include <vm/vm.h> 51 #include <vm/vm_param.h> 52 #include <vm/vm_object.h> 53 #include <vm/vm_page.h> 54 #include <vm/vm_pager.h> 55 #include <vm/vm_phys.h> 56 #include <vm/uma.h> 57 58 static void dev_pager_init(void); 59 static vm_object_t dev_pager_alloc(void *, vm_ooffset_t, vm_prot_t, 60 vm_ooffset_t, struct ucred *); 61 static void dev_pager_dealloc(vm_object_t); 62 static int dev_pager_getpages(vm_object_t, vm_page_t *, int, int); 63 static void dev_pager_putpages(vm_object_t, vm_page_t *, int, 64 boolean_t, int *); 65 static boolean_t dev_pager_haspage(vm_object_t, vm_pindex_t, int *, 66 int *); 67 static void dev_pager_free_page(vm_object_t object, vm_page_t m); 68 69 /* list of device pager objects */ 70 static struct pagerlst dev_pager_object_list; 71 /* protect list manipulation */ 72 static struct mtx dev_pager_mtx; 73 74 struct pagerops devicepagerops = { 75 .pgo_init = dev_pager_init, 76 .pgo_alloc = dev_pager_alloc, 77 .pgo_dealloc = dev_pager_dealloc, 78 .pgo_getpages = dev_pager_getpages, 79 .pgo_putpages = dev_pager_putpages, 80 .pgo_haspage = dev_pager_haspage, 81 }; 82 83 struct pagerops mgtdevicepagerops = { 84 .pgo_alloc = dev_pager_alloc, 85 .pgo_dealloc = dev_pager_dealloc, 86 .pgo_getpages = dev_pager_getpages, 87 .pgo_putpages = dev_pager_putpages, 88 .pgo_haspage = dev_pager_haspage, 89 }; 90 91 static int old_dev_pager_ctor(void *handle, vm_ooffset_t size, vm_prot_t prot, 92 vm_ooffset_t foff, struct ucred *cred, u_short *color); 93 static void old_dev_pager_dtor(void *handle); 94 static int old_dev_pager_fault(vm_object_t object, vm_ooffset_t offset, 95 int prot, vm_page_t *mres); 96 97 static struct cdev_pager_ops old_dev_pager_ops = { 98 .cdev_pg_ctor = old_dev_pager_ctor, 99 .cdev_pg_dtor = old_dev_pager_dtor, 100 .cdev_pg_fault = old_dev_pager_fault 101 }; 102 103 static void 104 dev_pager_init() 105 { 106 TAILQ_INIT(&dev_pager_object_list); 107 mtx_init(&dev_pager_mtx, "dev_pager list", NULL, MTX_DEF); 108 } 109 110 vm_object_t 111 cdev_pager_lookup(void *handle) 112 { 113 vm_object_t object; 114 115 mtx_lock(&dev_pager_mtx); 116 object = vm_pager_object_lookup(&dev_pager_object_list, handle); 117 mtx_unlock(&dev_pager_mtx); 118 return (object); 119 } 120 121 vm_object_t 122 cdev_pager_allocate(void *handle, enum obj_type tp, struct cdev_pager_ops *ops, 123 vm_ooffset_t size, vm_prot_t prot, vm_ooffset_t foff, struct ucred *cred) 124 { 125 vm_object_t object, object1; 126 vm_pindex_t pindex; 127 u_short color; 128 129 if (tp != OBJT_DEVICE && tp != OBJT_MGTDEVICE) 130 return (NULL); 131 132 /* 133 * Offset should be page aligned. 134 */ 135 if (foff & PAGE_MASK) 136 return (NULL); 137 138 size = round_page(size); 139 pindex = OFF_TO_IDX(foff + size); 140 141 if (ops->cdev_pg_ctor(handle, size, prot, foff, cred, &color) != 0) 142 return (NULL); 143 mtx_lock(&dev_pager_mtx); 144 145 /* 146 * Look up pager, creating as necessary. 147 */ 148 object1 = NULL; 149 object = vm_pager_object_lookup(&dev_pager_object_list, handle); 150 if (object == NULL) { 151 /* 152 * Allocate object and associate it with the pager. Initialize 153 * the object's pg_color based upon the physical address of the 154 * device's memory. 155 */ 156 mtx_unlock(&dev_pager_mtx); 157 object1 = vm_object_allocate(tp, pindex); 158 object1->flags |= OBJ_COLORED; 159 object1->pg_color = color; 160 object1->handle = handle; 161 object1->un_pager.devp.ops = ops; 162 object1->un_pager.devp.dev = handle; 163 TAILQ_INIT(&object1->un_pager.devp.devp_pglist); 164 mtx_lock(&dev_pager_mtx); 165 object = vm_pager_object_lookup(&dev_pager_object_list, handle); 166 if (object != NULL) { 167 /* 168 * We raced with other thread while allocating object. 169 */ 170 if (pindex > object->size) 171 object->size = pindex; 172 KASSERT(object->type == tp, 173 ("Inconsistent device pager type %p %d", object, tp)); 174 } else { 175 object = object1; 176 object1 = NULL; 177 object->handle = handle; 178 TAILQ_INSERT_TAIL(&dev_pager_object_list, object, 179 pager_object_list); 180 } 181 } else { 182 if (pindex > object->size) 183 object->size = pindex; 184 KASSERT(object->type == tp, 185 ("Inconsistent device pager type %p %d", object, tp)); 186 } 187 mtx_unlock(&dev_pager_mtx); 188 if (object1 != NULL) { 189 object1->handle = object1; 190 mtx_lock(&dev_pager_mtx); 191 TAILQ_INSERT_TAIL(&dev_pager_object_list, object1, 192 pager_object_list); 193 mtx_unlock(&dev_pager_mtx); 194 vm_object_deallocate(object1); 195 } 196 return (object); 197 } 198 199 static vm_object_t 200 dev_pager_alloc(void *handle, vm_ooffset_t size, vm_prot_t prot, 201 vm_ooffset_t foff, struct ucred *cred) 202 { 203 204 return (cdev_pager_allocate(handle, OBJT_DEVICE, &old_dev_pager_ops, 205 size, prot, foff, cred)); 206 } 207 208 void 209 cdev_pager_free_page(vm_object_t object, vm_page_t m) 210 { 211 212 VM_OBJECT_ASSERT_WLOCKED(object); 213 if (object->type == OBJT_MGTDEVICE) { 214 KASSERT((m->oflags & VPO_UNMANAGED) == 0, ("unmanaged %p", m)); 215 pmap_remove_all(m); 216 vm_page_lock(m); 217 vm_page_remove(m); 218 vm_page_unlock(m); 219 } else if (object->type == OBJT_DEVICE) 220 dev_pager_free_page(object, m); 221 } 222 223 static void 224 dev_pager_free_page(vm_object_t object, vm_page_t m) 225 { 226 227 VM_OBJECT_ASSERT_WLOCKED(object); 228 KASSERT((object->type == OBJT_DEVICE && 229 (m->oflags & VPO_UNMANAGED) != 0), 230 ("Managed device or page obj %p m %p", object, m)); 231 TAILQ_REMOVE(&object->un_pager.devp.devp_pglist, m, plinks.q); 232 vm_page_putfake(m); 233 } 234 235 static void 236 dev_pager_dealloc(object) 237 vm_object_t object; 238 { 239 vm_page_t m; 240 241 VM_OBJECT_WUNLOCK(object); 242 object->un_pager.devp.ops->cdev_pg_dtor(object->un_pager.devp.dev); 243 244 mtx_lock(&dev_pager_mtx); 245 TAILQ_REMOVE(&dev_pager_object_list, object, pager_object_list); 246 mtx_unlock(&dev_pager_mtx); 247 VM_OBJECT_WLOCK(object); 248 249 if (object->type == OBJT_DEVICE) { 250 /* 251 * Free up our fake pages. 252 */ 253 while ((m = TAILQ_FIRST(&object->un_pager.devp.devp_pglist)) 254 != NULL) 255 dev_pager_free_page(object, m); 256 } 257 object->handle = NULL; 258 object->type = OBJT_DEAD; 259 } 260 261 static int 262 dev_pager_getpages(vm_object_t object, vm_page_t *ma, int count, int reqpage) 263 { 264 int error, i; 265 266 VM_OBJECT_ASSERT_WLOCKED(object); 267 error = object->un_pager.devp.ops->cdev_pg_fault(object, 268 IDX_TO_OFF(ma[reqpage]->pindex), PROT_READ, &ma[reqpage]); 269 270 VM_OBJECT_ASSERT_WLOCKED(object); 271 272 for (i = 0; i < count; i++) { 273 if (i != reqpage) { 274 vm_page_lock(ma[i]); 275 vm_page_free(ma[i]); 276 vm_page_unlock(ma[i]); 277 } 278 } 279 280 if (error == VM_PAGER_OK) { 281 KASSERT((object->type == OBJT_DEVICE && 282 (ma[reqpage]->oflags & VPO_UNMANAGED) != 0) || 283 (object->type == OBJT_MGTDEVICE && 284 (ma[reqpage]->oflags & VPO_UNMANAGED) == 0), 285 ("Wrong page type %p %p", ma[reqpage], object)); 286 if (object->type == OBJT_DEVICE) { 287 TAILQ_INSERT_TAIL(&object->un_pager.devp.devp_pglist, 288 ma[reqpage], plinks.q); 289 } 290 } 291 292 return (error); 293 } 294 295 static int 296 old_dev_pager_fault(vm_object_t object, vm_ooffset_t offset, int prot, 297 vm_page_t *mres) 298 { 299 vm_paddr_t paddr; 300 vm_page_t m_paddr, page; 301 struct cdev *dev; 302 struct cdevsw *csw; 303 struct file *fpop; 304 struct thread *td; 305 vm_memattr_t memattr; 306 int ref, ret; 307 308 memattr = object->memattr; 309 310 VM_OBJECT_WUNLOCK(object); 311 312 dev = object->handle; 313 csw = dev_refthread(dev, &ref); 314 if (csw == NULL) { 315 VM_OBJECT_WLOCK(object); 316 return (VM_PAGER_FAIL); 317 } 318 td = curthread; 319 fpop = td->td_fpop; 320 td->td_fpop = NULL; 321 ret = csw->d_mmap(dev, offset, &paddr, prot, &memattr); 322 td->td_fpop = fpop; 323 dev_relthread(dev, ref); 324 if (ret != 0) { 325 printf( 326 "WARNING: dev_pager_getpage: map function returns error %d", ret); 327 VM_OBJECT_WLOCK(object); 328 return (VM_PAGER_FAIL); 329 } 330 331 /* If "paddr" is a real page, perform a sanity check on "memattr". */ 332 if ((m_paddr = vm_phys_paddr_to_vm_page(paddr)) != NULL && 333 pmap_page_get_memattr(m_paddr) != memattr) { 334 memattr = pmap_page_get_memattr(m_paddr); 335 printf( 336 "WARNING: A device driver has set \"memattr\" inconsistently.\n"); 337 } 338 if (((*mres)->flags & PG_FICTITIOUS) != 0) { 339 /* 340 * If the passed in result page is a fake page, update it with 341 * the new physical address. 342 */ 343 page = *mres; 344 VM_OBJECT_WLOCK(object); 345 vm_page_updatefake(page, paddr, memattr); 346 } else { 347 /* 348 * Replace the passed in reqpage page with our own fake page and 349 * free up the all of the original pages. 350 */ 351 page = vm_page_getfake(paddr, memattr); 352 VM_OBJECT_WLOCK(object); 353 if (vm_page_replace(page, object, (*mres)->pindex) != *mres) 354 panic("old_dev_pager_fault: invalid page replacement"); 355 vm_page_lock(*mres); 356 vm_page_free(*mres); 357 vm_page_unlock(*mres); 358 *mres = page; 359 } 360 page->valid = VM_PAGE_BITS_ALL; 361 return (VM_PAGER_OK); 362 } 363 364 static void 365 dev_pager_putpages(object, m, count, sync, rtvals) 366 vm_object_t object; 367 vm_page_t *m; 368 int count; 369 boolean_t sync; 370 int *rtvals; 371 { 372 373 panic("dev_pager_putpage called"); 374 } 375 376 static boolean_t 377 dev_pager_haspage(object, pindex, before, after) 378 vm_object_t object; 379 vm_pindex_t pindex; 380 int *before; 381 int *after; 382 { 383 if (before != NULL) 384 *before = 0; 385 if (after != NULL) 386 *after = 0; 387 return (TRUE); 388 } 389 390 static int 391 old_dev_pager_ctor(void *handle, vm_ooffset_t size, vm_prot_t prot, 392 vm_ooffset_t foff, struct ucred *cred, u_short *color) 393 { 394 struct cdev *dev; 395 struct cdevsw *csw; 396 vm_memattr_t dummy; 397 vm_ooffset_t off; 398 vm_paddr_t paddr; 399 unsigned int npages; 400 int ref; 401 402 /* 403 * Make sure this device can be mapped. 404 */ 405 dev = handle; 406 csw = dev_refthread(dev, &ref); 407 if (csw == NULL) 408 return (ENXIO); 409 410 /* 411 * Check that the specified range of the device allows the desired 412 * protection. 413 * 414 * XXX assumes VM_PROT_* == PROT_* 415 */ 416 npages = OFF_TO_IDX(size); 417 paddr = 0; /* Make paddr initialized for the case of size == 0. */ 418 for (off = foff; npages--; off += PAGE_SIZE) { 419 if (csw->d_mmap(dev, off, &paddr, (int)prot, &dummy) != 0) { 420 dev_relthread(dev, ref); 421 return (EINVAL); 422 } 423 } 424 425 dev_ref(dev); 426 dev_relthread(dev, ref); 427 *color = atop(paddr) - OFF_TO_IDX(off - PAGE_SIZE); 428 return (0); 429 } 430 431 static void 432 old_dev_pager_dtor(void *handle) 433 { 434 435 dev_rel(handle); 436 } 437