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