1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright (c) 1982, 1986, 1991, 1993 5 * The Regents of the University of California. All rights reserved. 6 * (c) UNIX System Laboratories, Inc. 7 * All or some portions of this file are derived from material licensed 8 * to the University of California by American Telephone and Telegraph 9 * Co. or Unix System Laboratories, Inc. and are reproduced herein with 10 * the permission of UNIX System Laboratories, Inc. 11 * 12 * Copyright (c) 2014 The FreeBSD Foundation 13 * 14 * Portions of this software were developed by Konstantin Belousov 15 * under sponsorship from the FreeBSD Foundation. 16 * 17 * Redistribution and use in source and binary forms, with or without 18 * modification, are permitted provided that the following conditions 19 * are met: 20 * 1. Redistributions of source code must retain the above copyright 21 * notice, this list of conditions and the following disclaimer. 22 * 2. Redistributions in binary form must reproduce the above copyright 23 * notice, this list of conditions and the following disclaimer in the 24 * documentation and/or other materials provided with the distribution. 25 * 3. Neither the name of the University nor the names of its contributors 26 * may be used to endorse or promote products derived from this software 27 * without specific prior written permission. 28 * 29 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 30 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 31 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 32 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 33 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 34 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 35 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 36 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 37 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 38 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 39 * SUCH DAMAGE. 40 */ 41 42 #include <sys/cdefs.h> 43 #include <sys/param.h> 44 #include <sys/systm.h> 45 #include <sys/kernel.h> 46 #include <sys/limits.h> 47 #include <sys/lock.h> 48 #include <sys/mman.h> 49 #include <sys/proc.h> 50 #include <sys/resourcevar.h> 51 #include <sys/rwlock.h> 52 #include <sys/sched.h> 53 #include <sys/sysctl.h> 54 #include <sys/vnode.h> 55 56 #include <vm/vm.h> 57 #include <vm/vm_param.h> 58 #include <vm/vm_extern.h> 59 #include <vm/vm_page.h> 60 #include <vm/vm_pageout.h> 61 #include <vm/vm_map.h> 62 63 #include <machine/bus.h> 64 65 SYSCTL_INT(_kern, KERN_IOV_MAX, iov_max, CTLFLAG_RD, SYSCTL_NULL_INT_PTR, UIO_MAXIOV, 66 "Maximum number of elements in an I/O vector; sysconf(_SC_IOV_MAX)"); 67 68 static int uiomove_faultflag(void *cp, int n, struct uio *uio, int nofault); 69 70 int 71 copyin_nofault(const void *udaddr, void *kaddr, size_t len) 72 { 73 int error, save; 74 75 save = vm_fault_disable_pagefaults(); 76 error = copyin(udaddr, kaddr, len); 77 vm_fault_enable_pagefaults(save); 78 return (error); 79 } 80 81 int 82 copyout_nofault(const void *kaddr, void *udaddr, size_t len) 83 { 84 int error, save; 85 86 save = vm_fault_disable_pagefaults(); 87 error = copyout(kaddr, udaddr, len); 88 vm_fault_enable_pagefaults(save); 89 return (error); 90 } 91 92 #define PHYS_PAGE_COUNT(len) (howmany(len, PAGE_SIZE) + 1) 93 94 int 95 physcopyin(void *src, vm_paddr_t dst, size_t len) 96 { 97 vm_page_t m[PHYS_PAGE_COUNT(len)]; 98 struct iovec iov[1]; 99 struct uio uio; 100 int i; 101 102 iov[0].iov_base = src; 103 iov[0].iov_len = len; 104 uio.uio_iov = iov; 105 uio.uio_iovcnt = 1; 106 uio.uio_offset = 0; 107 uio.uio_resid = len; 108 uio.uio_segflg = UIO_SYSSPACE; 109 uio.uio_rw = UIO_WRITE; 110 for (i = 0; i < PHYS_PAGE_COUNT(len); i++, dst += PAGE_SIZE) 111 m[i] = PHYS_TO_VM_PAGE(dst); 112 return (uiomove_fromphys(m, dst & PAGE_MASK, len, &uio)); 113 } 114 115 int 116 physcopyout(vm_paddr_t src, void *dst, size_t len) 117 { 118 vm_page_t m[PHYS_PAGE_COUNT(len)]; 119 struct iovec iov[1]; 120 struct uio uio; 121 int i; 122 123 iov[0].iov_base = dst; 124 iov[0].iov_len = len; 125 uio.uio_iov = iov; 126 uio.uio_iovcnt = 1; 127 uio.uio_offset = 0; 128 uio.uio_resid = len; 129 uio.uio_segflg = UIO_SYSSPACE; 130 uio.uio_rw = UIO_READ; 131 for (i = 0; i < PHYS_PAGE_COUNT(len); i++, src += PAGE_SIZE) 132 m[i] = PHYS_TO_VM_PAGE(src); 133 return (uiomove_fromphys(m, src & PAGE_MASK, len, &uio)); 134 } 135 136 #undef PHYS_PAGE_COUNT 137 138 int 139 physcopyin_vlist(bus_dma_segment_t *src, off_t offset, vm_paddr_t dst, 140 size_t len) 141 { 142 size_t seg_len; 143 int error; 144 145 error = 0; 146 while (offset >= src->ds_len) { 147 offset -= src->ds_len; 148 src++; 149 } 150 151 while (len > 0 && error == 0) { 152 seg_len = MIN(src->ds_len - offset, len); 153 error = physcopyin((void *)(uintptr_t)(src->ds_addr + offset), 154 dst, seg_len); 155 offset = 0; 156 src++; 157 len -= seg_len; 158 dst += seg_len; 159 } 160 161 return (error); 162 } 163 164 int 165 physcopyout_vlist(vm_paddr_t src, bus_dma_segment_t *dst, off_t offset, 166 size_t len) 167 { 168 size_t seg_len; 169 int error; 170 171 error = 0; 172 while (offset >= dst->ds_len) { 173 offset -= dst->ds_len; 174 dst++; 175 } 176 177 while (len > 0 && error == 0) { 178 seg_len = MIN(dst->ds_len - offset, len); 179 error = physcopyout(src, (void *)(uintptr_t)(dst->ds_addr + 180 offset), seg_len); 181 offset = 0; 182 dst++; 183 len -= seg_len; 184 src += seg_len; 185 } 186 187 return (error); 188 } 189 190 int 191 uiomove(void *cp, int n, struct uio *uio) 192 { 193 194 return (uiomove_faultflag(cp, n, uio, 0)); 195 } 196 197 int 198 uiomove_nofault(void *cp, int n, struct uio *uio) 199 { 200 201 return (uiomove_faultflag(cp, n, uio, 1)); 202 } 203 204 static int 205 uiomove_faultflag(void *cp, int n, struct uio *uio, int nofault) 206 { 207 struct iovec *iov; 208 size_t cnt; 209 int error, newflags, save; 210 211 save = error = 0; 212 213 KASSERT(uio->uio_rw == UIO_READ || uio->uio_rw == UIO_WRITE, 214 ("uiomove: mode")); 215 KASSERT(uio->uio_segflg != UIO_USERSPACE || uio->uio_td == curthread, 216 ("uiomove proc")); 217 KASSERT(uio->uio_resid >= 0, 218 ("%s: uio %p resid underflow", __func__, uio)); 219 220 if (uio->uio_segflg == UIO_USERSPACE) { 221 newflags = TDP_DEADLKTREAT; 222 if (nofault) { 223 /* 224 * Fail if a non-spurious page fault occurs. 225 */ 226 newflags |= TDP_NOFAULTING | TDP_RESETSPUR; 227 } else { 228 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL, 229 "Calling uiomove()"); 230 } 231 save = curthread_pflags_set(newflags); 232 } else { 233 KASSERT(nofault == 0, ("uiomove: nofault")); 234 } 235 236 while (n > 0 && uio->uio_resid) { 237 KASSERT(uio->uio_iovcnt > 0, 238 ("%s: uio %p iovcnt underflow", __func__, uio)); 239 240 iov = uio->uio_iov; 241 cnt = iov->iov_len; 242 if (cnt == 0) { 243 uio->uio_iov++; 244 uio->uio_iovcnt--; 245 continue; 246 } 247 if (cnt > n) 248 cnt = n; 249 250 switch (uio->uio_segflg) { 251 case UIO_USERSPACE: 252 maybe_yield(); 253 if (uio->uio_rw == UIO_READ) 254 error = copyout(cp, iov->iov_base, cnt); 255 else 256 error = copyin(iov->iov_base, cp, cnt); 257 if (error) 258 goto out; 259 break; 260 261 case UIO_SYSSPACE: 262 if (uio->uio_rw == UIO_READ) 263 bcopy(cp, iov->iov_base, cnt); 264 else 265 bcopy(iov->iov_base, cp, cnt); 266 break; 267 case UIO_NOCOPY: 268 break; 269 } 270 iov->iov_base = (char *)iov->iov_base + cnt; 271 iov->iov_len -= cnt; 272 uio->uio_resid -= cnt; 273 uio->uio_offset += cnt; 274 cp = (char *)cp + cnt; 275 n -= cnt; 276 } 277 out: 278 if (save) 279 curthread_pflags_restore(save); 280 return (error); 281 } 282 283 /* 284 * Wrapper for uiomove() that validates the arguments against a known-good 285 * kernel buffer. Currently, uiomove accepts a signed (n) argument, which 286 * is almost definitely a bad thing, so we catch that here as well. We 287 * return a runtime failure, but it might be desirable to generate a runtime 288 * assertion failure instead. 289 */ 290 int 291 uiomove_frombuf(void *buf, int buflen, struct uio *uio) 292 { 293 size_t offset, n; 294 295 if (uio->uio_offset < 0 || uio->uio_resid < 0 || 296 (offset = uio->uio_offset) != uio->uio_offset) 297 return (EINVAL); 298 if (buflen <= 0 || offset >= buflen) 299 return (0); 300 if ((n = buflen - offset) > IOSIZE_MAX) 301 return (EINVAL); 302 return (uiomove((char *)buf + offset, n, uio)); 303 } 304 305 /* 306 * Give next character to user as result of read. 307 */ 308 int 309 ureadc(int c, struct uio *uio) 310 { 311 struct iovec *iov; 312 char *iov_base; 313 314 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL, 315 "Calling ureadc()"); 316 317 again: 318 if (uio->uio_iovcnt == 0 || uio->uio_resid == 0) 319 panic("ureadc"); 320 iov = uio->uio_iov; 321 if (iov->iov_len == 0) { 322 uio->uio_iovcnt--; 323 uio->uio_iov++; 324 goto again; 325 } 326 switch (uio->uio_segflg) { 327 case UIO_USERSPACE: 328 if (subyte(iov->iov_base, c) < 0) 329 return (EFAULT); 330 break; 331 332 case UIO_SYSSPACE: 333 iov_base = iov->iov_base; 334 *iov_base = c; 335 break; 336 337 case UIO_NOCOPY: 338 break; 339 } 340 iov->iov_base = (char *)iov->iov_base + 1; 341 iov->iov_len--; 342 uio->uio_resid--; 343 uio->uio_offset++; 344 return (0); 345 } 346 347 int 348 copyiniov(const struct iovec *iovp, u_int iovcnt, struct iovec **iov, int error) 349 { 350 u_int iovlen; 351 352 *iov = NULL; 353 if (iovcnt > UIO_MAXIOV) 354 return (error); 355 iovlen = iovcnt * sizeof (struct iovec); 356 *iov = malloc(iovlen, M_IOV, M_WAITOK); 357 error = copyin(iovp, *iov, iovlen); 358 if (error) { 359 free(*iov, M_IOV); 360 *iov = NULL; 361 } 362 return (error); 363 } 364 365 int 366 copyinuio(const struct iovec *iovp, u_int iovcnt, struct uio **uiop) 367 { 368 struct iovec *iov; 369 struct uio *uio; 370 u_int iovlen; 371 int error, i; 372 373 *uiop = NULL; 374 if (iovcnt > UIO_MAXIOV) 375 return (EINVAL); 376 iovlen = iovcnt * sizeof (struct iovec); 377 uio = malloc(iovlen + sizeof *uio, M_IOV, M_WAITOK); 378 iov = (struct iovec *)(uio + 1); 379 error = copyin(iovp, iov, iovlen); 380 if (error) { 381 free(uio, M_IOV); 382 return (error); 383 } 384 uio->uio_iov = iov; 385 uio->uio_iovcnt = iovcnt; 386 uio->uio_segflg = UIO_USERSPACE; 387 uio->uio_offset = -1; 388 uio->uio_resid = 0; 389 for (i = 0; i < iovcnt; i++) { 390 if (iov->iov_len > IOSIZE_MAX - uio->uio_resid) { 391 free(uio, M_IOV); 392 return (EINVAL); 393 } 394 uio->uio_resid += iov->iov_len; 395 iov++; 396 } 397 *uiop = uio; 398 return (0); 399 } 400 401 struct uio * 402 cloneuio(struct uio *uiop) 403 { 404 struct uio *uio; 405 int iovlen; 406 407 iovlen = uiop->uio_iovcnt * sizeof (struct iovec); 408 uio = malloc(iovlen + sizeof *uio, M_IOV, M_WAITOK); 409 *uio = *uiop; 410 uio->uio_iov = (struct iovec *)(uio + 1); 411 bcopy(uiop->uio_iov, uio->uio_iov, iovlen); 412 return (uio); 413 } 414 415 /* 416 * Map some anonymous memory in user space of size sz, rounded up to the page 417 * boundary. 418 */ 419 int 420 copyout_map(struct thread *td, vm_offset_t *addr, size_t sz) 421 { 422 struct vmspace *vms; 423 int error; 424 vm_size_t size; 425 426 vms = td->td_proc->p_vmspace; 427 428 /* 429 * Map somewhere after heap in process memory. 430 */ 431 *addr = round_page((vm_offset_t)vms->vm_daddr + 432 lim_max(td, RLIMIT_DATA)); 433 434 /* round size up to page boundary */ 435 size = (vm_size_t)round_page(sz); 436 if (size == 0) 437 return (EINVAL); 438 error = vm_mmap_object(&vms->vm_map, addr, size, VM_PROT_READ | 439 VM_PROT_WRITE, VM_PROT_ALL, MAP_PRIVATE | MAP_ANON, NULL, 0, 440 FALSE, td); 441 return (error); 442 } 443 444 /* 445 * Unmap memory in user space. 446 */ 447 int 448 copyout_unmap(struct thread *td, vm_offset_t addr, size_t sz) 449 { 450 vm_map_t map; 451 vm_size_t size; 452 453 if (sz == 0) 454 return (0); 455 456 map = &td->td_proc->p_vmspace->vm_map; 457 size = (vm_size_t)round_page(sz); 458 459 if (vm_map_remove(map, addr, addr + size) != KERN_SUCCESS) 460 return (EINVAL); 461 462 return (0); 463 } 464 465 int32_t 466 fuword32(volatile const void *addr) 467 { 468 int rv; 469 int32_t val; 470 471 rv = fueword32(addr, &val); 472 return (rv == -1 ? -1 : val); 473 } 474 475 #ifdef _LP64 476 int64_t 477 fuword64(volatile const void *addr) 478 { 479 int rv; 480 int64_t val; 481 482 rv = fueword64(addr, &val); 483 return (rv == -1 ? -1 : val); 484 } 485 #endif /* _LP64 */ 486 487 long 488 fuword(volatile const void *addr) 489 { 490 long val; 491 int rv; 492 493 rv = fueword(addr, &val); 494 return (rv == -1 ? -1 : val); 495 } 496 497 uint32_t 498 casuword32(volatile uint32_t *addr, uint32_t old, uint32_t new) 499 { 500 int rv; 501 uint32_t val; 502 503 rv = casueword32(addr, old, &val, new); 504 return (rv == -1 ? -1 : val); 505 } 506 507 u_long 508 casuword(volatile u_long *addr, u_long old, u_long new) 509 { 510 int rv; 511 u_long val; 512 513 rv = casueword(addr, old, &val, new); 514 return (rv == -1 ? -1 : val); 515 } 516