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, int, int *); 64 static boolean_t dev_pager_haspage(vm_object_t, vm_pindex_t, int *, int *); 65 static void dev_pager_free_page(vm_object_t object, vm_page_t m); 66 67 /* list of device pager objects */ 68 static struct pagerlst dev_pager_object_list; 69 /* protect list manipulation */ 70 static struct mtx dev_pager_mtx; 71 72 struct pagerops devicepagerops = { 73 .pgo_init = dev_pager_init, 74 .pgo_alloc = dev_pager_alloc, 75 .pgo_dealloc = dev_pager_dealloc, 76 .pgo_getpages = dev_pager_getpages, 77 .pgo_putpages = dev_pager_putpages, 78 .pgo_haspage = dev_pager_haspage, 79 }; 80 81 struct pagerops mgtdevicepagerops = { 82 .pgo_alloc = dev_pager_alloc, 83 .pgo_dealloc = dev_pager_dealloc, 84 .pgo_getpages = dev_pager_getpages, 85 .pgo_putpages = dev_pager_putpages, 86 .pgo_haspage = dev_pager_haspage, 87 }; 88 89 static int old_dev_pager_ctor(void *handle, vm_ooffset_t size, vm_prot_t prot, 90 vm_ooffset_t foff, struct ucred *cred, u_short *color); 91 static void old_dev_pager_dtor(void *handle); 92 static int old_dev_pager_fault(vm_object_t object, vm_ooffset_t offset, 93 int prot, vm_page_t *mres); 94 95 static struct cdev_pager_ops old_dev_pager_ops = { 96 .cdev_pg_ctor = old_dev_pager_ctor, 97 .cdev_pg_dtor = old_dev_pager_dtor, 98 .cdev_pg_fault = old_dev_pager_fault 99 }; 100 101 static void 102 dev_pager_init(void) 103 { 104 105 TAILQ_INIT(&dev_pager_object_list); 106 mtx_init(&dev_pager_mtx, "dev_pager list", NULL, MTX_DEF); 107 } 108 109 vm_object_t 110 cdev_pager_lookup(void *handle) 111 { 112 vm_object_t object; 113 114 mtx_lock(&dev_pager_mtx); 115 object = vm_pager_object_lookup(&dev_pager_object_list, handle); 116 mtx_unlock(&dev_pager_mtx); 117 return (object); 118 } 119 120 vm_object_t 121 cdev_pager_allocate(void *handle, enum obj_type tp, struct cdev_pager_ops *ops, 122 vm_ooffset_t size, vm_prot_t prot, vm_ooffset_t foff, struct ucred *cred) 123 { 124 vm_object_t object, object1; 125 vm_pindex_t pindex; 126 u_short color; 127 128 if (tp != OBJT_DEVICE && tp != OBJT_MGTDEVICE) 129 return (NULL); 130 131 /* 132 * Offset should be page aligned. 133 */ 134 if (foff & PAGE_MASK) 135 return (NULL); 136 137 size = round_page(size); 138 pindex = OFF_TO_IDX(foff + size); 139 140 if (ops->cdev_pg_ctor(handle, size, prot, foff, cred, &color) != 0) 141 return (NULL); 142 mtx_lock(&dev_pager_mtx); 143 144 /* 145 * Look up pager, creating as necessary. 146 */ 147 object1 = NULL; 148 object = vm_pager_object_lookup(&dev_pager_object_list, handle); 149 if (object == NULL) { 150 /* 151 * Allocate object and associate it with the pager. Initialize 152 * the object's pg_color based upon the physical address of the 153 * device's memory. 154 */ 155 mtx_unlock(&dev_pager_mtx); 156 object1 = vm_object_allocate(tp, pindex); 157 object1->flags |= OBJ_COLORED; 158 object1->pg_color = color; 159 object1->handle = handle; 160 object1->un_pager.devp.ops = ops; 161 object1->un_pager.devp.dev = handle; 162 TAILQ_INIT(&object1->un_pager.devp.devp_pglist); 163 mtx_lock(&dev_pager_mtx); 164 object = vm_pager_object_lookup(&dev_pager_object_list, handle); 165 if (object != NULL) { 166 /* 167 * We raced with other thread while allocating object. 168 */ 169 if (pindex > object->size) 170 object->size = pindex; 171 KASSERT(object->type == tp, 172 ("Inconsistent device pager type %p %d", object, tp)); 173 } else { 174 object = object1; 175 object1 = NULL; 176 object->handle = handle; 177 TAILQ_INSERT_TAIL(&dev_pager_object_list, object, 178 pager_object_list); 179 } 180 } else { 181 if (pindex > object->size) 182 object->size = pindex; 183 KASSERT(object->type == tp, 184 ("Inconsistent device pager type %p %d", object, tp)); 185 } 186 mtx_unlock(&dev_pager_mtx); 187 if (object1 != NULL) { 188 object1->handle = object1; 189 mtx_lock(&dev_pager_mtx); 190 TAILQ_INSERT_TAIL(&dev_pager_object_list, object1, 191 pager_object_list); 192 mtx_unlock(&dev_pager_mtx); 193 vm_object_deallocate(object1); 194 } 195 return (object); 196 } 197 198 static vm_object_t 199 dev_pager_alloc(void *handle, vm_ooffset_t size, vm_prot_t prot, 200 vm_ooffset_t foff, struct ucred *cred) 201 { 202 203 return (cdev_pager_allocate(handle, OBJT_DEVICE, &old_dev_pager_ops, 204 size, prot, foff, cred)); 205 } 206 207 void 208 cdev_pager_free_page(vm_object_t object, vm_page_t m) 209 { 210 211 VM_OBJECT_ASSERT_WLOCKED(object); 212 if (object->type == OBJT_MGTDEVICE) { 213 KASSERT((m->oflags & VPO_UNMANAGED) == 0, ("unmanaged %p", m)); 214 pmap_remove_all(m); 215 vm_page_lock(m); 216 vm_page_remove(m); 217 vm_page_unlock(m); 218 } else if (object->type == OBJT_DEVICE) 219 dev_pager_free_page(object, m); 220 } 221 222 static void 223 dev_pager_free_page(vm_object_t object, vm_page_t m) 224 { 225 226 VM_OBJECT_ASSERT_WLOCKED(object); 227 KASSERT((object->type == OBJT_DEVICE && 228 (m->oflags & VPO_UNMANAGED) != 0), 229 ("Managed device or page obj %p m %p", object, m)); 230 TAILQ_REMOVE(&object->un_pager.devp.devp_pglist, m, plinks.q); 231 vm_page_putfake(m); 232 } 233 234 static void 235 dev_pager_dealloc(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 object->handle = NULL; 256 object->type = OBJT_DEAD; 257 } 258 259 static int 260 dev_pager_getpages(vm_object_t object, vm_page_t *ma, int count, int reqpage) 261 { 262 int error; 263 264 VM_OBJECT_ASSERT_WLOCKED(object); 265 error = object->un_pager.devp.ops->cdev_pg_fault(object, 266 IDX_TO_OFF(ma[reqpage]->pindex), PROT_READ, &ma[reqpage]); 267 268 VM_OBJECT_ASSERT_WLOCKED(object); 269 270 vm_pager_free_nonreq(object, ma, reqpage, count, TRUE); 271 272 if (error == VM_PAGER_OK) { 273 KASSERT((object->type == OBJT_DEVICE && 274 (ma[reqpage]->oflags & VPO_UNMANAGED) != 0) || 275 (object->type == OBJT_MGTDEVICE && 276 (ma[reqpage]->oflags & VPO_UNMANAGED) == 0), 277 ("Wrong page type %p %p", ma[reqpage], object)); 278 if (object->type == OBJT_DEVICE) { 279 TAILQ_INSERT_TAIL(&object->un_pager.devp.devp_pglist, 280 ma[reqpage], plinks.q); 281 } 282 } 283 284 return (error); 285 } 286 287 static int 288 old_dev_pager_fault(vm_object_t object, vm_ooffset_t offset, int prot, 289 vm_page_t *mres) 290 { 291 vm_paddr_t paddr; 292 vm_page_t m_paddr, page; 293 struct cdev *dev; 294 struct cdevsw *csw; 295 struct file *fpop; 296 struct thread *td; 297 vm_memattr_t memattr; 298 int ref, ret; 299 300 memattr = object->memattr; 301 302 VM_OBJECT_WUNLOCK(object); 303 304 dev = object->handle; 305 csw = dev_refthread(dev, &ref); 306 if (csw == NULL) { 307 VM_OBJECT_WLOCK(object); 308 return (VM_PAGER_FAIL); 309 } 310 td = curthread; 311 fpop = td->td_fpop; 312 td->td_fpop = NULL; 313 ret = csw->d_mmap(dev, offset, &paddr, prot, &memattr); 314 td->td_fpop = fpop; 315 dev_relthread(dev, ref); 316 if (ret != 0) { 317 printf( 318 "WARNING: dev_pager_getpage: map function returns error %d", ret); 319 VM_OBJECT_WLOCK(object); 320 return (VM_PAGER_FAIL); 321 } 322 323 /* If "paddr" is a real page, perform a sanity check on "memattr". */ 324 if ((m_paddr = vm_phys_paddr_to_vm_page(paddr)) != NULL && 325 pmap_page_get_memattr(m_paddr) != memattr) { 326 memattr = pmap_page_get_memattr(m_paddr); 327 printf( 328 "WARNING: A device driver has set \"memattr\" inconsistently.\n"); 329 } 330 if (((*mres)->flags & PG_FICTITIOUS) != 0) { 331 /* 332 * If the passed in result page is a fake page, update it with 333 * the new physical address. 334 */ 335 page = *mres; 336 VM_OBJECT_WLOCK(object); 337 vm_page_updatefake(page, paddr, memattr); 338 } else { 339 /* 340 * Replace the passed in reqpage page with our own fake page and 341 * free up the all of the original pages. 342 */ 343 page = vm_page_getfake(paddr, memattr); 344 VM_OBJECT_WLOCK(object); 345 if (vm_page_replace(page, object, (*mres)->pindex) != *mres) 346 panic("old_dev_pager_fault: invalid page replacement"); 347 vm_page_lock(*mres); 348 vm_page_free(*mres); 349 vm_page_unlock(*mres); 350 *mres = page; 351 } 352 page->valid = VM_PAGE_BITS_ALL; 353 return (VM_PAGER_OK); 354 } 355 356 static void 357 dev_pager_putpages(vm_object_t object, vm_page_t *m, int count, int flags, 358 int *rtvals) 359 { 360 361 panic("dev_pager_putpage called"); 362 } 363 364 static boolean_t 365 dev_pager_haspage(vm_object_t object, vm_pindex_t pindex, int *before, 366 int *after) 367 { 368 369 if (before != NULL) 370 *before = 0; 371 if (after != NULL) 372 *after = 0; 373 return (TRUE); 374 } 375 376 static int 377 old_dev_pager_ctor(void *handle, vm_ooffset_t size, vm_prot_t prot, 378 vm_ooffset_t foff, struct ucred *cred, u_short *color) 379 { 380 struct cdev *dev; 381 struct cdevsw *csw; 382 vm_memattr_t dummy; 383 vm_ooffset_t off; 384 vm_paddr_t paddr; 385 unsigned int npages; 386 int ref; 387 388 /* 389 * Make sure this device can be mapped. 390 */ 391 dev = handle; 392 csw = dev_refthread(dev, &ref); 393 if (csw == NULL) 394 return (ENXIO); 395 396 /* 397 * Check that the specified range of the device allows the desired 398 * protection. 399 * 400 * XXX assumes VM_PROT_* == PROT_* 401 */ 402 npages = OFF_TO_IDX(size); 403 paddr = 0; /* Make paddr initialized for the case of size == 0. */ 404 for (off = foff; npages--; off += PAGE_SIZE) { 405 if (csw->d_mmap(dev, off, &paddr, (int)prot, &dummy) != 0) { 406 dev_relthread(dev, ref); 407 return (EINVAL); 408 } 409 } 410 411 dev_ref(dev); 412 dev_relthread(dev, ref); 413 *color = atop(paddr) - OFF_TO_IDX(off - PAGE_SIZE); 414 return (0); 415 } 416 417 static void 418 old_dev_pager_dtor(void *handle) 419 { 420 421 dev_rel(handle); 422 } 423