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 } else { 173 object = object1; 174 object1 = NULL; 175 object->handle = handle; 176 TAILQ_INSERT_TAIL(&dev_pager_object_list, object, 177 pager_object_list); 178 KASSERT(object->type == tp, 179 ("Inconsistent device pager type %p %d", object, tp)); 180 } 181 } else { 182 if (pindex > object->size) 183 object->size = pindex; 184 } 185 mtx_unlock(&dev_pager_mtx); 186 if (object1 != NULL) { 187 object1->handle = object1; 188 mtx_lock(&dev_pager_mtx); 189 TAILQ_INSERT_TAIL(&dev_pager_object_list, object1, 190 pager_object_list); 191 mtx_unlock(&dev_pager_mtx); 192 vm_object_deallocate(object1); 193 } 194 return (object); 195 } 196 197 static vm_object_t 198 dev_pager_alloc(void *handle, vm_ooffset_t size, vm_prot_t prot, 199 vm_ooffset_t foff, struct ucred *cred) 200 { 201 202 return (cdev_pager_allocate(handle, OBJT_DEVICE, &old_dev_pager_ops, 203 size, prot, foff, cred)); 204 } 205 206 void 207 cdev_pager_free_page(vm_object_t object, vm_page_t m) 208 { 209 210 VM_OBJECT_ASSERT_WLOCKED(object); 211 if (object->type == OBJT_MGTDEVICE) { 212 KASSERT((m->oflags & VPO_UNMANAGED) == 0, ("unmanaged %p", m)); 213 pmap_remove_all(m); 214 vm_page_lock(m); 215 vm_page_remove(m); 216 vm_page_unlock(m); 217 } else if (object->type == OBJT_DEVICE) 218 dev_pager_free_page(object, m); 219 } 220 221 static void 222 dev_pager_free_page(vm_object_t object, vm_page_t m) 223 { 224 225 VM_OBJECT_ASSERT_WLOCKED(object); 226 KASSERT((object->type == OBJT_DEVICE && 227 (m->oflags & VPO_UNMANAGED) != 0), 228 ("Managed device or page obj %p m %p", object, m)); 229 TAILQ_REMOVE(&object->un_pager.devp.devp_pglist, m, pageq); 230 vm_page_putfake(m); 231 } 232 233 static void 234 dev_pager_dealloc(object) 235 vm_object_t object; 236 { 237 vm_page_t m; 238 239 VM_OBJECT_WUNLOCK(object); 240 object->un_pager.devp.ops->cdev_pg_dtor(object->un_pager.devp.dev); 241 242 mtx_lock(&dev_pager_mtx); 243 TAILQ_REMOVE(&dev_pager_object_list, object, pager_object_list); 244 mtx_unlock(&dev_pager_mtx); 245 VM_OBJECT_WLOCK(object); 246 247 if (object->type == OBJT_DEVICE) { 248 /* 249 * Free up our fake pages. 250 */ 251 while ((m = TAILQ_FIRST(&object->un_pager.devp.devp_pglist)) 252 != NULL) 253 dev_pager_free_page(object, m); 254 } 255 } 256 257 static int 258 dev_pager_getpages(vm_object_t object, vm_page_t *ma, int count, int reqpage) 259 { 260 int error, i; 261 262 VM_OBJECT_ASSERT_WLOCKED(object); 263 error = object->un_pager.devp.ops->cdev_pg_fault(object, 264 IDX_TO_OFF(ma[reqpage]->pindex), PROT_READ, &ma[reqpage]); 265 266 VM_OBJECT_ASSERT_WLOCKED(object); 267 268 for (i = 0; i < count; i++) { 269 if (i != reqpage) { 270 vm_page_lock(ma[i]); 271 vm_page_free(ma[i]); 272 vm_page_unlock(ma[i]); 273 } 274 } 275 276 if (error == VM_PAGER_OK) { 277 KASSERT((object->type == OBJT_DEVICE && 278 (ma[reqpage]->oflags & VPO_UNMANAGED) != 0) || 279 (object->type == OBJT_MGTDEVICE && 280 (ma[reqpage]->oflags & VPO_UNMANAGED) == 0), 281 ("Wrong page type %p %p", ma[reqpage], object)); 282 if (object->type == OBJT_DEVICE) { 283 TAILQ_INSERT_TAIL(&object->un_pager.devp.devp_pglist, 284 ma[reqpage], pageq); 285 } 286 } 287 288 return (error); 289 } 290 291 static int 292 old_dev_pager_fault(vm_object_t object, vm_ooffset_t offset, int prot, 293 vm_page_t *mres) 294 { 295 vm_pindex_t pidx; 296 vm_paddr_t paddr; 297 vm_page_t m_paddr, page; 298 struct cdev *dev; 299 struct cdevsw *csw; 300 struct file *fpop; 301 struct thread *td; 302 vm_memattr_t memattr; 303 int ref, ret; 304 305 pidx = OFF_TO_IDX(offset); 306 memattr = object->memattr; 307 308 VM_OBJECT_WUNLOCK(object); 309 310 dev = object->handle; 311 csw = dev_refthread(dev, &ref); 312 if (csw == NULL) { 313 VM_OBJECT_WLOCK(object); 314 return (VM_PAGER_FAIL); 315 } 316 td = curthread; 317 fpop = td->td_fpop; 318 td->td_fpop = NULL; 319 ret = csw->d_mmap(dev, offset, &paddr, prot, &memattr); 320 td->td_fpop = fpop; 321 dev_relthread(dev, ref); 322 if (ret != 0) { 323 printf( 324 "WARNING: dev_pager_getpage: map function returns error %d", ret); 325 VM_OBJECT_WLOCK(object); 326 return (VM_PAGER_FAIL); 327 } 328 329 /* If "paddr" is a real page, perform a sanity check on "memattr". */ 330 if ((m_paddr = vm_phys_paddr_to_vm_page(paddr)) != NULL && 331 pmap_page_get_memattr(m_paddr) != memattr) { 332 memattr = pmap_page_get_memattr(m_paddr); 333 printf( 334 "WARNING: A device driver has set \"memattr\" inconsistently.\n"); 335 } 336 if (((*mres)->flags & PG_FICTITIOUS) != 0) { 337 /* 338 * If the passed in result page is a fake page, update it with 339 * the new physical address. 340 */ 341 page = *mres; 342 VM_OBJECT_WLOCK(object); 343 vm_page_updatefake(page, paddr, memattr); 344 } else { 345 /* 346 * Replace the passed in reqpage page with our own fake page and 347 * free up the all of the original pages. 348 */ 349 page = vm_page_getfake(paddr, memattr); 350 VM_OBJECT_WLOCK(object); 351 vm_page_lock(*mres); 352 vm_page_free(*mres); 353 vm_page_unlock(*mres); 354 *mres = page; 355 vm_page_insert(page, object, pidx); 356 } 357 page->valid = VM_PAGE_BITS_ALL; 358 return (VM_PAGER_OK); 359 } 360 361 static void 362 dev_pager_putpages(object, m, count, sync, rtvals) 363 vm_object_t object; 364 vm_page_t *m; 365 int count; 366 boolean_t sync; 367 int *rtvals; 368 { 369 370 panic("dev_pager_putpage called"); 371 } 372 373 static boolean_t 374 dev_pager_haspage(object, pindex, before, after) 375 vm_object_t object; 376 vm_pindex_t pindex; 377 int *before; 378 int *after; 379 { 380 if (before != NULL) 381 *before = 0; 382 if (after != NULL) 383 *after = 0; 384 return (TRUE); 385 } 386 387 static int 388 old_dev_pager_ctor(void *handle, vm_ooffset_t size, vm_prot_t prot, 389 vm_ooffset_t foff, struct ucred *cred, u_short *color) 390 { 391 struct cdev *dev; 392 struct cdevsw *csw; 393 vm_memattr_t dummy; 394 vm_ooffset_t off; 395 vm_paddr_t paddr; 396 unsigned int npages; 397 int ref; 398 399 /* 400 * Make sure this device can be mapped. 401 */ 402 dev = handle; 403 csw = dev_refthread(dev, &ref); 404 if (csw == NULL) 405 return (ENXIO); 406 407 /* 408 * Check that the specified range of the device allows the desired 409 * protection. 410 * 411 * XXX assumes VM_PROT_* == PROT_* 412 */ 413 npages = OFF_TO_IDX(size); 414 for (off = foff; npages--; off += PAGE_SIZE) { 415 if (csw->d_mmap(dev, off, &paddr, (int)prot, &dummy) != 0) { 416 dev_relthread(dev, ref); 417 return (EINVAL); 418 } 419 } 420 421 dev_ref(dev); 422 dev_relthread(dev, ref); 423 *color = atop(paddr) - OFF_TO_IDX(off - PAGE_SIZE); 424 return (0); 425 } 426 427 static void 428 old_dev_pager_dtor(void *handle) 429 { 430 431 dev_rel(handle); 432 } 433