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/sx.h> 48 49 #include <vm/vm.h> 50 #include <vm/vm_object.h> 51 #include <vm/vm_page.h> 52 #include <vm/vm_pager.h> 53 #include <vm/uma.h> 54 55 static void dev_pager_init(void); 56 static vm_object_t dev_pager_alloc(void *, vm_ooffset_t, vm_prot_t, 57 vm_ooffset_t, struct ucred *); 58 static void dev_pager_dealloc(vm_object_t); 59 static int dev_pager_getpages(vm_object_t, vm_page_t *, int, int); 60 static void dev_pager_putpages(vm_object_t, vm_page_t *, int, 61 boolean_t, int *); 62 static boolean_t dev_pager_haspage(vm_object_t, vm_pindex_t, int *, 63 int *); 64 static void dev_pager_free_page(vm_object_t object, vm_page_t m); 65 66 /* list of device pager objects */ 67 static struct pagerlst dev_pager_object_list; 68 /* protect list manipulation */ 69 static struct mtx dev_pager_mtx; 70 71 struct pagerops devicepagerops = { 72 .pgo_init = dev_pager_init, 73 .pgo_alloc = dev_pager_alloc, 74 .pgo_dealloc = dev_pager_dealloc, 75 .pgo_getpages = dev_pager_getpages, 76 .pgo_putpages = dev_pager_putpages, 77 .pgo_haspage = dev_pager_haspage, 78 }; 79 80 struct pagerops mgtdevicepagerops = { 81 .pgo_alloc = dev_pager_alloc, 82 .pgo_dealloc = dev_pager_dealloc, 83 .pgo_getpages = dev_pager_getpages, 84 .pgo_putpages = dev_pager_putpages, 85 .pgo_haspage = dev_pager_haspage, 86 }; 87 88 static int old_dev_pager_ctor(void *handle, vm_ooffset_t size, vm_prot_t prot, 89 vm_ooffset_t foff, struct ucred *cred, u_short *color); 90 static void old_dev_pager_dtor(void *handle); 91 static int old_dev_pager_fault(vm_object_t object, vm_ooffset_t offset, 92 int prot, vm_page_t *mres); 93 94 static struct cdev_pager_ops old_dev_pager_ops = { 95 .cdev_pg_ctor = old_dev_pager_ctor, 96 .cdev_pg_dtor = old_dev_pager_dtor, 97 .cdev_pg_fault = old_dev_pager_fault 98 }; 99 100 static void 101 dev_pager_init() 102 { 103 TAILQ_INIT(&dev_pager_object_list); 104 mtx_init(&dev_pager_mtx, "dev_pager list", NULL, MTX_DEF); 105 } 106 107 vm_object_t 108 cdev_pager_lookup(void *handle) 109 { 110 vm_object_t object; 111 112 mtx_lock(&dev_pager_mtx); 113 object = vm_pager_object_lookup(&dev_pager_object_list, handle); 114 vm_object_reference(object); 115 mtx_unlock(&dev_pager_mtx); 116 return (object); 117 } 118 119 vm_object_t 120 cdev_pager_allocate(void *handle, enum obj_type tp, struct cdev_pager_ops *ops, 121 vm_ooffset_t size, vm_prot_t prot, vm_ooffset_t foff, struct ucred *cred) 122 { 123 vm_object_t object, object1; 124 vm_pindex_t pindex; 125 u_short color; 126 127 if (tp != OBJT_DEVICE && tp != OBJT_MGTDEVICE) 128 return (NULL); 129 130 /* 131 * Offset should be page aligned. 132 */ 133 if (foff & PAGE_MASK) 134 return (NULL); 135 136 size = round_page(size); 137 pindex = OFF_TO_IDX(foff + size); 138 139 if (ops->cdev_pg_ctor(handle, size, prot, foff, cred, &color) != 0) 140 return (NULL); 141 mtx_lock(&dev_pager_mtx); 142 143 /* 144 * Look up pager, creating as necessary. 145 */ 146 object1 = NULL; 147 object = vm_pager_object_lookup(&dev_pager_object_list, handle); 148 if (object == NULL) { 149 /* 150 * Allocate object and associate it with the pager. Initialize 151 * the object's pg_color based upon the physical address of the 152 * device's memory. 153 */ 154 mtx_unlock(&dev_pager_mtx); 155 object1 = vm_object_allocate(tp, pindex); 156 object1->flags |= OBJ_COLORED; 157 object1->pg_color = color; 158 object1->handle = handle; 159 object1->un_pager.devp.ops = ops; 160 TAILQ_INIT(&object1->un_pager.devp.devp_pglist); 161 mtx_lock(&dev_pager_mtx); 162 object = vm_pager_object_lookup(&dev_pager_object_list, handle); 163 if (object != NULL) { 164 /* 165 * We raced with other thread while allocating object. 166 */ 167 if (pindex > object->size) 168 object->size = pindex; 169 } else { 170 object = object1; 171 object1 = NULL; 172 object->handle = handle; 173 TAILQ_INSERT_TAIL(&dev_pager_object_list, object, 174 pager_object_list); 175 KASSERT(object->type == tp, 176 ("Inconsistent device pager type %p %d", object, tp)); 177 } 178 } else { 179 if (pindex > object->size) 180 object->size = pindex; 181 } 182 mtx_unlock(&dev_pager_mtx); 183 if (object1 != NULL) { 184 object1->handle = object1; 185 mtx_lock(&dev_pager_mtx); 186 TAILQ_INSERT_TAIL(&dev_pager_object_list, object1, 187 pager_object_list); 188 mtx_unlock(&dev_pager_mtx); 189 vm_object_deallocate(object1); 190 } 191 return (object); 192 } 193 194 static vm_object_t 195 dev_pager_alloc(void *handle, vm_ooffset_t size, vm_prot_t prot, 196 vm_ooffset_t foff, struct ucred *cred) 197 { 198 199 return (cdev_pager_allocate(handle, OBJT_DEVICE, &old_dev_pager_ops, 200 size, prot, foff, cred)); 201 } 202 203 void 204 cdev_pager_free_page(vm_object_t object, vm_page_t m) 205 { 206 207 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 208 if (object->type == OBJT_MGTDEVICE) { 209 KASSERT((m->oflags & VPO_UNMANAGED) == 0, ("unmanaged %p", m)); 210 pmap_remove_all(m); 211 vm_page_lock(m); 212 vm_page_remove(m); 213 vm_page_unlock(m); 214 } else if (object->type == OBJT_DEVICE) 215 dev_pager_free_page(object, m); 216 } 217 218 static void 219 dev_pager_free_page(vm_object_t object, vm_page_t m) 220 { 221 222 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 223 KASSERT((object->type == OBJT_DEVICE && 224 (m->oflags & VPO_UNMANAGED) != 0), 225 ("Managed device or page obj %p m %p", object, m)); 226 TAILQ_REMOVE(&object->un_pager.devp.devp_pglist, m, pageq); 227 vm_page_putfake(m); 228 } 229 230 static void 231 dev_pager_dealloc(object) 232 vm_object_t object; 233 { 234 vm_page_t m; 235 236 VM_OBJECT_UNLOCK(object); 237 object->un_pager.devp.ops->cdev_pg_dtor(object->handle); 238 239 mtx_lock(&dev_pager_mtx); 240 TAILQ_REMOVE(&dev_pager_object_list, object, pager_object_list); 241 mtx_unlock(&dev_pager_mtx); 242 VM_OBJECT_LOCK(object); 243 244 if (object->type == OBJT_DEVICE) { 245 /* 246 * Free up our fake pages. 247 */ 248 while ((m = TAILQ_FIRST(&object->un_pager.devp.devp_pglist)) 249 != NULL) 250 dev_pager_free_page(object, m); 251 } 252 } 253 254 static int 255 dev_pager_getpages(vm_object_t object, vm_page_t *ma, int count, int reqpage) 256 { 257 int error, i; 258 259 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 260 error = object->un_pager.devp.ops->cdev_pg_fault(object, 261 IDX_TO_OFF(ma[reqpage]->pindex), PROT_READ, &ma[reqpage]); 262 263 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 264 265 for (i = 0; i < count; i++) { 266 if (i != reqpage) { 267 vm_page_lock(ma[i]); 268 vm_page_free(ma[i]); 269 vm_page_unlock(ma[i]); 270 } 271 } 272 273 if (error == VM_PAGER_OK) { 274 KASSERT((object->type == OBJT_DEVICE && 275 (ma[reqpage]->oflags & VPO_UNMANAGED) != 0) || 276 (object->type == OBJT_MGTDEVICE && 277 (ma[reqpage]->oflags & VPO_UNMANAGED) == 0), 278 ("Wrong page type %p %p", ma[reqpage], object)); 279 if (object->type == OBJT_DEVICE) { 280 TAILQ_INSERT_TAIL(&object->un_pager.devp.devp_pglist, 281 ma[reqpage], pageq); 282 } 283 } 284 285 return (error); 286 } 287 288 static int 289 old_dev_pager_fault(vm_object_t object, vm_ooffset_t offset, int prot, 290 vm_page_t *mres) 291 { 292 vm_pindex_t pidx; 293 vm_paddr_t paddr; 294 vm_page_t m_paddr, page; 295 struct cdev *dev; 296 struct cdevsw *csw; 297 struct file *fpop; 298 struct thread *td; 299 vm_memattr_t memattr; 300 int ref, ret; 301 302 pidx = OFF_TO_IDX(offset); 303 memattr = object->memattr; 304 305 VM_OBJECT_UNLOCK(object); 306 307 dev = object->handle; 308 csw = dev_refthread(dev, &ref); 309 if (csw == NULL) { 310 VM_OBJECT_LOCK(object); 311 return (VM_PAGER_FAIL); 312 } 313 td = curthread; 314 fpop = td->td_fpop; 315 td->td_fpop = NULL; 316 ret = csw->d_mmap(dev, offset, &paddr, prot, &memattr); 317 td->td_fpop = fpop; 318 dev_relthread(dev, ref); 319 if (ret != 0) { 320 printf( 321 "WARNING: dev_pager_getpage: map function returns error %d", ret); 322 VM_OBJECT_LOCK(object); 323 return (VM_PAGER_FAIL); 324 } 325 326 /* If "paddr" is a real page, perform a sanity check on "memattr". */ 327 if ((m_paddr = vm_phys_paddr_to_vm_page(paddr)) != NULL && 328 pmap_page_get_memattr(m_paddr) != memattr) { 329 memattr = pmap_page_get_memattr(m_paddr); 330 printf( 331 "WARNING: A device driver has set \"memattr\" inconsistently.\n"); 332 } 333 if (((*mres)->flags & PG_FICTITIOUS) != 0) { 334 /* 335 * If the passed in result page is a fake page, update it with 336 * the new physical address. 337 */ 338 page = *mres; 339 VM_OBJECT_LOCK(object); 340 vm_page_updatefake(page, paddr, memattr); 341 } else { 342 /* 343 * Replace the passed in reqpage page with our own fake page and 344 * free up the all of the original pages. 345 */ 346 page = vm_page_getfake(paddr, memattr); 347 VM_OBJECT_LOCK(object); 348 vm_page_lock(*mres); 349 vm_page_free(*mres); 350 vm_page_unlock(*mres); 351 *mres = page; 352 vm_page_insert(page, object, pidx); 353 } 354 page->valid = VM_PAGE_BITS_ALL; 355 return (VM_PAGER_OK); 356 } 357 358 static void 359 dev_pager_putpages(object, m, count, sync, rtvals) 360 vm_object_t object; 361 vm_page_t *m; 362 int count; 363 boolean_t sync; 364 int *rtvals; 365 { 366 367 panic("dev_pager_putpage called"); 368 } 369 370 static boolean_t 371 dev_pager_haspage(object, pindex, before, after) 372 vm_object_t object; 373 vm_pindex_t pindex; 374 int *before; 375 int *after; 376 { 377 if (before != NULL) 378 *before = 0; 379 if (after != NULL) 380 *after = 0; 381 return (TRUE); 382 } 383 384 static int 385 old_dev_pager_ctor(void *handle, vm_ooffset_t size, vm_prot_t prot, 386 vm_ooffset_t foff, struct ucred *cred, u_short *color) 387 { 388 struct cdev *dev; 389 struct cdevsw *csw; 390 vm_memattr_t dummy; 391 vm_ooffset_t off; 392 vm_paddr_t paddr; 393 unsigned int npages; 394 int ref; 395 396 /* 397 * Make sure this device can be mapped. 398 */ 399 dev = handle; 400 csw = dev_refthread(dev, &ref); 401 if (csw == NULL) 402 return (ENXIO); 403 404 /* 405 * Check that the specified range of the device allows the desired 406 * protection. 407 * 408 * XXX assumes VM_PROT_* == PROT_* 409 */ 410 npages = OFF_TO_IDX(size); 411 for (off = foff; npages--; off += PAGE_SIZE) { 412 if (csw->d_mmap(dev, off, &paddr, (int)prot, &dummy) != 0) { 413 dev_relthread(dev, ref); 414 return (EINVAL); 415 } 416 } 417 418 dev_ref(dev); 419 dev_relthread(dev, ref); 420 *color = atop(paddr) - OFF_TO_IDX(off - PAGE_SIZE); 421 return (0); 422 } 423 424 static void 425 old_dev_pager_dtor(void *handle) 426 { 427 428 dev_rel(handle); 429 } 430