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_param.h> 51 #include <vm/vm_object.h> 52 #include <vm/vm_page.h> 53 #include <vm/vm_pager.h> 54 #include <vm/vm_phys.h> 55 #include <vm/uma.h> 56 57 static void dev_pager_init(void); 58 static vm_object_t dev_pager_alloc(void *, vm_ooffset_t, vm_prot_t, 59 vm_ooffset_t, struct ucred *); 60 static void dev_pager_dealloc(vm_object_t); 61 static int dev_pager_getpages(vm_object_t, vm_page_t *, int, int); 62 static void dev_pager_putpages(vm_object_t, vm_page_t *, int, 63 boolean_t, int *); 64 static boolean_t dev_pager_haspage(vm_object_t, vm_pindex_t, int *, 65 int *); 66 static void dev_pager_free_page(vm_object_t object, vm_page_t m); 67 68 /* list of device pager objects */ 69 static struct pagerlst dev_pager_object_list; 70 /* protect list manipulation */ 71 static struct mtx dev_pager_mtx; 72 73 struct pagerops devicepagerops = { 74 .pgo_init = dev_pager_init, 75 .pgo_alloc = dev_pager_alloc, 76 .pgo_dealloc = dev_pager_dealloc, 77 .pgo_getpages = dev_pager_getpages, 78 .pgo_putpages = dev_pager_putpages, 79 .pgo_haspage = dev_pager_haspage, 80 }; 81 82 struct pagerops mgtdevicepagerops = { 83 .pgo_alloc = dev_pager_alloc, 84 .pgo_dealloc = dev_pager_dealloc, 85 .pgo_getpages = dev_pager_getpages, 86 .pgo_putpages = dev_pager_putpages, 87 .pgo_haspage = dev_pager_haspage, 88 }; 89 90 static int old_dev_pager_ctor(void *handle, vm_ooffset_t size, vm_prot_t prot, 91 vm_ooffset_t foff, struct ucred *cred, u_short *color); 92 static void old_dev_pager_dtor(void *handle); 93 static int old_dev_pager_fault(vm_object_t object, vm_ooffset_t offset, 94 int prot, vm_page_t *mres); 95 96 static struct cdev_pager_ops old_dev_pager_ops = { 97 .cdev_pg_ctor = old_dev_pager_ctor, 98 .cdev_pg_dtor = old_dev_pager_dtor, 99 .cdev_pg_fault = old_dev_pager_fault 100 }; 101 102 static void 103 dev_pager_init() 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 } else { 172 object = object1; 173 object1 = NULL; 174 object->handle = handle; 175 TAILQ_INSERT_TAIL(&dev_pager_object_list, object, 176 pager_object_list); 177 KASSERT(object->type == tp, 178 ("Inconsistent device pager type %p %d", object, tp)); 179 } 180 } else { 181 if (pindex > object->size) 182 object->size = pindex; 183 } 184 mtx_unlock(&dev_pager_mtx); 185 if (object1 != NULL) { 186 object1->handle = object1; 187 mtx_lock(&dev_pager_mtx); 188 TAILQ_INSERT_TAIL(&dev_pager_object_list, object1, 189 pager_object_list); 190 mtx_unlock(&dev_pager_mtx); 191 vm_object_deallocate(object1); 192 } 193 return (object); 194 } 195 196 static vm_object_t 197 dev_pager_alloc(void *handle, vm_ooffset_t size, vm_prot_t prot, 198 vm_ooffset_t foff, struct ucred *cred) 199 { 200 201 return (cdev_pager_allocate(handle, OBJT_DEVICE, &old_dev_pager_ops, 202 size, prot, foff, cred)); 203 } 204 205 void 206 cdev_pager_free_page(vm_object_t object, vm_page_t m) 207 { 208 209 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 210 if (object->type == OBJT_MGTDEVICE) { 211 KASSERT((m->oflags & VPO_UNMANAGED) == 0, ("unmanaged %p", m)); 212 pmap_remove_all(m); 213 vm_page_lock(m); 214 vm_page_remove(m); 215 vm_page_unlock(m); 216 } else if (object->type == OBJT_DEVICE) 217 dev_pager_free_page(object, m); 218 } 219 220 static void 221 dev_pager_free_page(vm_object_t object, vm_page_t m) 222 { 223 224 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 225 KASSERT((object->type == OBJT_DEVICE && 226 (m->oflags & VPO_UNMANAGED) != 0), 227 ("Managed device or page obj %p m %p", object, m)); 228 TAILQ_REMOVE(&object->un_pager.devp.devp_pglist, m, pageq); 229 vm_page_putfake(m); 230 } 231 232 static void 233 dev_pager_dealloc(object) 234 vm_object_t object; 235 { 236 vm_page_t m; 237 238 VM_OBJECT_UNLOCK(object); 239 object->un_pager.devp.ops->cdev_pg_dtor(object->un_pager.devp.dev); 240 241 mtx_lock(&dev_pager_mtx); 242 TAILQ_REMOVE(&dev_pager_object_list, object, pager_object_list); 243 mtx_unlock(&dev_pager_mtx); 244 VM_OBJECT_LOCK(object); 245 246 if (object->type == OBJT_DEVICE) { 247 /* 248 * Free up our fake pages. 249 */ 250 while ((m = TAILQ_FIRST(&object->un_pager.devp.devp_pglist)) 251 != NULL) 252 dev_pager_free_page(object, m); 253 } 254 } 255 256 static int 257 dev_pager_getpages(vm_object_t object, vm_page_t *ma, int count, int reqpage) 258 { 259 int error, i; 260 261 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 262 error = object->un_pager.devp.ops->cdev_pg_fault(object, 263 IDX_TO_OFF(ma[reqpage]->pindex), PROT_READ, &ma[reqpage]); 264 265 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 266 267 for (i = 0; i < count; i++) { 268 if (i != reqpage) { 269 vm_page_lock(ma[i]); 270 vm_page_free(ma[i]); 271 vm_page_unlock(ma[i]); 272 } 273 } 274 275 if (error == VM_PAGER_OK) { 276 KASSERT((object->type == OBJT_DEVICE && 277 (ma[reqpage]->oflags & VPO_UNMANAGED) != 0) || 278 (object->type == OBJT_MGTDEVICE && 279 (ma[reqpage]->oflags & VPO_UNMANAGED) == 0), 280 ("Wrong page type %p %p", ma[reqpage], object)); 281 if (object->type == OBJT_DEVICE) { 282 TAILQ_INSERT_TAIL(&object->un_pager.devp.devp_pglist, 283 ma[reqpage], pageq); 284 } 285 } 286 287 return (error); 288 } 289 290 static int 291 old_dev_pager_fault(vm_object_t object, vm_ooffset_t offset, int prot, 292 vm_page_t *mres) 293 { 294 vm_pindex_t pidx; 295 vm_paddr_t paddr; 296 vm_page_t m_paddr, page; 297 struct cdev *dev; 298 struct cdevsw *csw; 299 struct file *fpop; 300 struct thread *td; 301 vm_memattr_t memattr; 302 int ref, ret; 303 304 pidx = OFF_TO_IDX(offset); 305 memattr = object->memattr; 306 307 VM_OBJECT_UNLOCK(object); 308 309 dev = object->handle; 310 csw = dev_refthread(dev, &ref); 311 if (csw == NULL) { 312 VM_OBJECT_LOCK(object); 313 return (VM_PAGER_FAIL); 314 } 315 td = curthread; 316 fpop = td->td_fpop; 317 td->td_fpop = NULL; 318 ret = csw->d_mmap(dev, offset, &paddr, prot, &memattr); 319 td->td_fpop = fpop; 320 dev_relthread(dev, ref); 321 if (ret != 0) { 322 printf( 323 "WARNING: dev_pager_getpage: map function returns error %d", ret); 324 VM_OBJECT_LOCK(object); 325 return (VM_PAGER_FAIL); 326 } 327 328 /* If "paddr" is a real page, perform a sanity check on "memattr". */ 329 if ((m_paddr = vm_phys_paddr_to_vm_page(paddr)) != NULL && 330 pmap_page_get_memattr(m_paddr) != memattr) { 331 memattr = pmap_page_get_memattr(m_paddr); 332 printf( 333 "WARNING: A device driver has set \"memattr\" inconsistently.\n"); 334 } 335 if (((*mres)->flags & PG_FICTITIOUS) != 0) { 336 /* 337 * If the passed in result page is a fake page, update it with 338 * the new physical address. 339 */ 340 page = *mres; 341 VM_OBJECT_LOCK(object); 342 vm_page_updatefake(page, paddr, memattr); 343 } else { 344 /* 345 * Replace the passed in reqpage page with our own fake page and 346 * free up the all of the original pages. 347 */ 348 page = vm_page_getfake(paddr, memattr); 349 VM_OBJECT_LOCK(object); 350 vm_page_lock(*mres); 351 vm_page_free(*mres); 352 vm_page_unlock(*mres); 353 *mres = page; 354 vm_page_insert(page, object, pidx); 355 } 356 page->valid = VM_PAGE_BITS_ALL; 357 return (VM_PAGER_OK); 358 } 359 360 static void 361 dev_pager_putpages(object, m, count, sync, rtvals) 362 vm_object_t object; 363 vm_page_t *m; 364 int count; 365 boolean_t sync; 366 int *rtvals; 367 { 368 369 panic("dev_pager_putpage called"); 370 } 371 372 static boolean_t 373 dev_pager_haspage(object, pindex, before, after) 374 vm_object_t object; 375 vm_pindex_t pindex; 376 int *before; 377 int *after; 378 { 379 if (before != NULL) 380 *before = 0; 381 if (after != NULL) 382 *after = 0; 383 return (TRUE); 384 } 385 386 static int 387 old_dev_pager_ctor(void *handle, vm_ooffset_t size, vm_prot_t prot, 388 vm_ooffset_t foff, struct ucred *cred, u_short *color) 389 { 390 struct cdev *dev; 391 struct cdevsw *csw; 392 vm_memattr_t dummy; 393 vm_ooffset_t off; 394 vm_paddr_t paddr; 395 unsigned int npages; 396 int ref; 397 398 /* 399 * Make sure this device can be mapped. 400 */ 401 dev = handle; 402 csw = dev_refthread(dev, &ref); 403 if (csw == NULL) 404 return (ENXIO); 405 406 /* 407 * Check that the specified range of the device allows the desired 408 * protection. 409 * 410 * XXX assumes VM_PROT_* == PROT_* 411 */ 412 npages = OFF_TO_IDX(size); 413 for (off = foff; npages--; off += PAGE_SIZE) { 414 if (csw->d_mmap(dev, off, &paddr, (int)prot, &dummy) != 0) { 415 dev_relthread(dev, ref); 416 return (EINVAL); 417 } 418 } 419 420 dev_ref(dev); 421 dev_relthread(dev, ref); 422 *color = atop(paddr) - OFF_TO_IDX(off - PAGE_SIZE); 423 return (0); 424 } 425 426 static void 427 old_dev_pager_dtor(void *handle) 428 { 429 430 dev_rel(handle); 431 } 432