| 1 | /* |
| 2 | * Copyright (c) 1982, 1986, 1989, 1993 |
| 3 | * The Regents of the University of California. All rights reserved. |
| 4 | * (c) UNIX System Laboratories, Inc. |
| 5 | * All or some portions of this file are derived from material licensed |
| 6 | * to the University of California by American Telephone and Telegraph |
| 7 | * Co. or Unix System Laboratories, Inc. and are reproduced herein with |
| 8 | * the permission of UNIX System Laboratories, Inc. |
| 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 | * 3. All advertising materials mentioning features or use of this software |
| 19 | * must display the following acknowledgement: |
| 20 | * This product includes software developed by the University of |
| 21 | * California, Berkeley and its contributors. |
| 22 | * 4. Neither the name of the University nor the names of its contributors |
| 23 | * may be used to endorse or promote products derived from this software |
| 24 | * without specific prior written permission. |
| 25 | * |
| 26 | * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND |
| 27 | * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| 28 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
| 29 | * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE |
| 30 | * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
| 31 | * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
| 32 | * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
| 33 | * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
| 34 | * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
| 35 | * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
| 36 | * SUCH DAMAGE. |
| 37 | * |
| 38 | * @(#)sys_generic.c 8.5 (Berkeley) 1/21/94 |
| 39 | * $FreeBSD: src/sys/kern/sys_generic.c,v 1.55.2.10 2001/03/17 10:39:32 peter Exp $ |
| 40 | * $DragonFly: src/sys/kern/sys_generic.c,v 1.9 2003/07/26 19:42:11 rob Exp $ |
| 41 | */ |
| 42 | |
| 43 | #include "opt_ktrace.h" |
| 44 | |
| 45 | #include <sys/param.h> |
| 46 | #include <sys/systm.h> |
| 47 | #include <sys/sysproto.h> |
| 48 | #include <sys/filedesc.h> |
| 49 | #include <sys/filio.h> |
| 50 | #include <sys/fcntl.h> |
| 51 | #include <sys/file.h> |
| 52 | #include <sys/proc.h> |
| 53 | #include <sys/signalvar.h> |
| 54 | #include <sys/socketvar.h> |
| 55 | #include <sys/uio.h> |
| 56 | #include <sys/kernel.h> |
| 57 | #include <sys/malloc.h> |
| 58 | #include <sys/poll.h> |
| 59 | #include <sys/resourcevar.h> |
| 60 | #include <sys/sysctl.h> |
| 61 | #include <sys/sysent.h> |
| 62 | #include <sys/buf.h> |
| 63 | #ifdef KTRACE |
| 64 | #include <sys/ktrace.h> |
| 65 | #endif |
| 66 | #include <vm/vm.h> |
| 67 | #include <vm/vm_page.h> |
| 68 | #include <sys/file2.h> |
| 69 | |
| 70 | #include <machine/limits.h> |
| 71 | |
| 72 | static MALLOC_DEFINE(M_IOCTLOPS, "ioctlops", "ioctl data buffer"); |
| 73 | static MALLOC_DEFINE(M_SELECT, "select", "select() buffer"); |
| 74 | MALLOC_DEFINE(M_IOV, "iov", "large iov's"); |
| 75 | |
| 76 | static int pollscan __P((struct proc *, struct pollfd *, u_int, int *)); |
| 77 | static int selscan __P((struct proc *, fd_mask **, fd_mask **, |
| 78 | int, int *)); |
| 79 | static int dofileread __P((struct file *, int, void *, |
| 80 | size_t, off_t, int, int *)); |
| 81 | static int dofilewrite __P((struct file *, int, |
| 82 | const void *, size_t, off_t, int, int *)); |
| 83 | |
| 84 | struct file* |
| 85 | holdfp(fdp, fd, flag) |
| 86 | struct filedesc* fdp; |
| 87 | int fd, flag; |
| 88 | { |
| 89 | struct file* fp; |
| 90 | |
| 91 | if (((u_int)fd) >= fdp->fd_nfiles || |
| 92 | (fp = fdp->fd_ofiles[fd]) == NULL || |
| 93 | (fp->f_flag & flag) == 0) { |
| 94 | return (NULL); |
| 95 | } |
| 96 | fhold(fp); |
| 97 | return (fp); |
| 98 | } |
| 99 | |
| 100 | /* |
| 101 | * Read system call. |
| 102 | */ |
| 103 | int |
| 104 | read(struct read_args *uap) |
| 105 | { |
| 106 | struct thread *td = curthread; |
| 107 | struct proc *p = td->td_proc; |
| 108 | struct file *fp; |
| 109 | int error; |
| 110 | |
| 111 | KKASSERT(p); |
| 112 | if ((fp = holdfp(p->p_fd, uap->fd, FREAD)) == NULL) |
| 113 | return (EBADF); |
| 114 | error = dofileread(fp, uap->fd, uap->buf, uap->nbyte, (off_t)-1, 0, |
| 115 | &uap->lmsg.u.ms_result); |
| 116 | fdrop(fp, td); |
| 117 | return(error); |
| 118 | } |
| 119 | |
| 120 | /* |
| 121 | * Pread system call |
| 122 | */ |
| 123 | int |
| 124 | pread(struct pread_args *uap) |
| 125 | { |
| 126 | struct thread *td = curthread; |
| 127 | struct proc *p = td->td_proc; |
| 128 | struct file *fp; |
| 129 | int error; |
| 130 | |
| 131 | KKASSERT(p); |
| 132 | if ((fp = holdfp(p->p_fd, uap->fd, FREAD)) == NULL) |
| 133 | return (EBADF); |
| 134 | if (fp->f_type != DTYPE_VNODE) { |
| 135 | error = ESPIPE; |
| 136 | } else { |
| 137 | error = dofileread(fp, uap->fd, uap->buf, uap->nbyte, |
| 138 | uap->offset, FOF_OFFSET, &uap->lmsg.u.ms_result); |
| 139 | } |
| 140 | fdrop(fp, td); |
| 141 | return(error); |
| 142 | } |
| 143 | |
| 144 | /* |
| 145 | * Code common for read and pread |
| 146 | */ |
| 147 | int |
| 148 | dofileread(fp, fd, buf, nbyte, offset, flags, res) |
| 149 | struct file *fp; |
| 150 | int fd, flags; |
| 151 | void *buf; |
| 152 | size_t nbyte; |
| 153 | off_t offset; |
| 154 | int *res; |
| 155 | { |
| 156 | struct thread *td = curthread; |
| 157 | struct proc *p = td->td_proc; |
| 158 | struct uio auio; |
| 159 | struct iovec aiov; |
| 160 | long cnt, error = 0; |
| 161 | #ifdef KTRACE |
| 162 | struct iovec ktriov; |
| 163 | struct uio ktruio; |
| 164 | int didktr = 0; |
| 165 | #endif |
| 166 | |
| 167 | aiov.iov_base = (caddr_t)buf; |
| 168 | aiov.iov_len = nbyte; |
| 169 | auio.uio_iov = &aiov; |
| 170 | auio.uio_iovcnt = 1; |
| 171 | auio.uio_offset = offset; |
| 172 | if (nbyte > INT_MAX) |
| 173 | return (EINVAL); |
| 174 | auio.uio_resid = nbyte; |
| 175 | auio.uio_rw = UIO_READ; |
| 176 | auio.uio_segflg = UIO_USERSPACE; |
| 177 | auio.uio_td = td; |
| 178 | #ifdef KTRACE |
| 179 | /* |
| 180 | * if tracing, save a copy of iovec |
| 181 | */ |
| 182 | if (KTRPOINT(td, KTR_GENIO)) { |
| 183 | ktriov = aiov; |
| 184 | ktruio = auio; |
| 185 | didktr = 1; |
| 186 | } |
| 187 | #endif |
| 188 | cnt = nbyte; |
| 189 | |
| 190 | if ((error = fo_read(fp, &auio, fp->f_cred, flags, td))) { |
| 191 | if (auio.uio_resid != cnt && (error == ERESTART || |
| 192 | error == EINTR || error == EWOULDBLOCK)) |
| 193 | error = 0; |
| 194 | } |
| 195 | cnt -= auio.uio_resid; |
| 196 | #ifdef KTRACE |
| 197 | if (didktr && error == 0) { |
| 198 | ktruio.uio_iov = &ktriov; |
| 199 | ktruio.uio_resid = cnt; |
| 200 | ktrgenio(p->p_tracep, fd, UIO_READ, &ktruio, error); |
| 201 | } |
| 202 | #endif |
| 203 | *res = cnt; |
| 204 | return (error); |
| 205 | } |
| 206 | |
| 207 | /* |
| 208 | * Scatter read system call. |
| 209 | */ |
| 210 | int |
| 211 | readv(struct readv_args *uap) |
| 212 | { |
| 213 | struct thread *td = curthread; |
| 214 | struct proc *p = td->td_proc; |
| 215 | struct file *fp; |
| 216 | struct filedesc *fdp = p->p_fd; |
| 217 | struct uio auio; |
| 218 | struct iovec *iov; |
| 219 | struct iovec *needfree; |
| 220 | struct iovec aiov[UIO_SMALLIOV]; |
| 221 | long i, cnt, error = 0; |
| 222 | u_int iovlen; |
| 223 | #ifdef KTRACE |
| 224 | struct iovec *ktriov = NULL; |
| 225 | struct uio ktruio; |
| 226 | #endif |
| 227 | |
| 228 | if ((fp = holdfp(fdp, uap->fd, FREAD)) == NULL) |
| 229 | return (EBADF); |
| 230 | /* note: can't use iovlen until iovcnt is validated */ |
| 231 | iovlen = uap->iovcnt * sizeof (struct iovec); |
| 232 | if (uap->iovcnt > UIO_SMALLIOV) { |
| 233 | if (uap->iovcnt > UIO_MAXIOV) |
| 234 | return (EINVAL); |
| 235 | MALLOC(iov, struct iovec *, iovlen, M_IOV, M_WAITOK); |
| 236 | needfree = iov; |
| 237 | } else { |
| 238 | iov = aiov; |
| 239 | needfree = NULL; |
| 240 | } |
| 241 | auio.uio_iov = iov; |
| 242 | auio.uio_iovcnt = uap->iovcnt; |
| 243 | auio.uio_rw = UIO_READ; |
| 244 | auio.uio_segflg = UIO_USERSPACE; |
| 245 | auio.uio_td = td; |
| 246 | auio.uio_offset = -1; |
| 247 | if ((error = copyin((caddr_t)uap->iovp, (caddr_t)iov, iovlen))) |
| 248 | goto done; |
| 249 | auio.uio_resid = 0; |
| 250 | for (i = 0; i < uap->iovcnt; i++) { |
| 251 | if (iov->iov_len > INT_MAX - auio.uio_resid) { |
| 252 | error = EINVAL; |
| 253 | goto done; |
| 254 | } |
| 255 | auio.uio_resid += iov->iov_len; |
| 256 | iov++; |
| 257 | } |
| 258 | #ifdef KTRACE |
| 259 | /* |
| 260 | * if tracing, save a copy of iovec |
| 261 | */ |
| 262 | if (KTRPOINT(td, KTR_GENIO)) { |
| 263 | MALLOC(ktriov, struct iovec *, iovlen, M_TEMP, M_WAITOK); |
| 264 | bcopy((caddr_t)auio.uio_iov, (caddr_t)ktriov, iovlen); |
| 265 | ktruio = auio; |
| 266 | } |
| 267 | #endif |
| 268 | cnt = auio.uio_resid; |
| 269 | if ((error = fo_read(fp, &auio, fp->f_cred, 0, td))) { |
| 270 | if (auio.uio_resid != cnt && (error == ERESTART || |
| 271 | error == EINTR || error == EWOULDBLOCK)) |
| 272 | error = 0; |
| 273 | } |
| 274 | cnt -= auio.uio_resid; |
| 275 | #ifdef KTRACE |
| 276 | if (ktriov != NULL) { |
| 277 | if (error == 0) { |
| 278 | ktruio.uio_iov = ktriov; |
| 279 | ktruio.uio_resid = cnt; |
| 280 | ktrgenio(p->p_tracep, uap->fd, UIO_READ, &ktruio, |
| 281 | error); |
| 282 | } |
| 283 | FREE(ktriov, M_TEMP); |
| 284 | } |
| 285 | #endif |
| 286 | uap->lmsg.u.ms_result = cnt; |
| 287 | done: |
| 288 | fdrop(fp, td); |
| 289 | if (needfree) |
| 290 | FREE(needfree, M_IOV); |
| 291 | return (error); |
| 292 | } |
| 293 | |
| 294 | /* |
| 295 | * Write system call |
| 296 | */ |
| 297 | int |
| 298 | write(struct write_args *uap) |
| 299 | { |
| 300 | struct thread *td = curthread; |
| 301 | struct proc *p = td->td_proc; |
| 302 | struct file *fp; |
| 303 | int error; |
| 304 | |
| 305 | KKASSERT(p); |
| 306 | |
| 307 | if ((fp = holdfp(p->p_fd, uap->fd, FWRITE)) == NULL) |
| 308 | return (EBADF); |
| 309 | error = dofilewrite(fp, uap->fd, uap->buf, uap->nbyte, (off_t)-1, 0, |
| 310 | &uap->lmsg.u.ms_result); |
| 311 | fdrop(fp, td); |
| 312 | return(error); |
| 313 | } |
| 314 | |
| 315 | /* |
| 316 | * Pwrite system call |
| 317 | */ |
| 318 | int |
| 319 | pwrite(struct pwrite_args *uap) |
| 320 | { |
| 321 | struct thread *td = curthread; |
| 322 | struct proc *p = td->td_proc; |
| 323 | struct file *fp; |
| 324 | int error; |
| 325 | |
| 326 | KKASSERT(p); |
| 327 | if ((fp = holdfp(p->p_fd, uap->fd, FWRITE)) == NULL) |
| 328 | return (EBADF); |
| 329 | if (fp->f_type != DTYPE_VNODE) { |
| 330 | error = ESPIPE; |
| 331 | } else { |
| 332 | error = dofilewrite(fp, uap->fd, uap->buf, uap->nbyte, |
| 333 | uap->offset, FOF_OFFSET, &uap->lmsg.u.ms_result); |
| 334 | } |
| 335 | fdrop(fp, td); |
| 336 | return(error); |
| 337 | } |
| 338 | |
| 339 | static int |
| 340 | dofilewrite( |
| 341 | struct file *fp, |
| 342 | int fd, |
| 343 | const void *buf, |
| 344 | size_t nbyte, |
| 345 | off_t offset, |
| 346 | int flags, |
| 347 | int *res |
| 348 | ) { |
| 349 | struct thread *td = curthread; |
| 350 | struct proc *p = td->td_proc; |
| 351 | struct uio auio; |
| 352 | struct iovec aiov; |
| 353 | long cnt, error = 0; |
| 354 | #ifdef KTRACE |
| 355 | struct iovec ktriov; |
| 356 | struct uio ktruio; |
| 357 | int didktr = 0; |
| 358 | #endif |
| 359 | |
| 360 | aiov.iov_base = (void *)(uintptr_t)buf; |
| 361 | aiov.iov_len = nbyte; |
| 362 | auio.uio_iov = &aiov; |
| 363 | auio.uio_iovcnt = 1; |
| 364 | auio.uio_offset = offset; |
| 365 | if (nbyte > INT_MAX) |
| 366 | return (EINVAL); |
| 367 | auio.uio_resid = nbyte; |
| 368 | auio.uio_rw = UIO_WRITE; |
| 369 | auio.uio_segflg = UIO_USERSPACE; |
| 370 | auio.uio_td = td; |
| 371 | #ifdef KTRACE |
| 372 | /* |
| 373 | * if tracing, save a copy of iovec and uio |
| 374 | */ |
| 375 | if (KTRPOINT(td, KTR_GENIO)) { |
| 376 | ktriov = aiov; |
| 377 | ktruio = auio; |
| 378 | didktr = 1; |
| 379 | } |
| 380 | #endif |
| 381 | cnt = nbyte; |
| 382 | if (fp->f_type == DTYPE_VNODE) |
| 383 | bwillwrite(); |
| 384 | if ((error = fo_write(fp, &auio, fp->f_cred, flags, td))) { |
| 385 | if (auio.uio_resid != cnt && (error == ERESTART || |
| 386 | error == EINTR || error == EWOULDBLOCK)) |
| 387 | error = 0; |
| 388 | if (error == EPIPE) |
| 389 | psignal(p, SIGPIPE); |
| 390 | } |
| 391 | cnt -= auio.uio_resid; |
| 392 | #ifdef KTRACE |
| 393 | if (didktr && error == 0) { |
| 394 | ktruio.uio_iov = &ktriov; |
| 395 | ktruio.uio_resid = cnt; |
| 396 | ktrgenio(p->p_tracep, fd, UIO_WRITE, &ktruio, error); |
| 397 | } |
| 398 | #endif |
| 399 | *res = cnt; |
| 400 | return (error); |
| 401 | } |
| 402 | |
| 403 | /* |
| 404 | * Gather write system call |
| 405 | */ |
| 406 | int |
| 407 | writev(struct writev_args *uap) |
| 408 | { |
| 409 | struct thread *td = curthread; |
| 410 | struct proc *p = td->td_proc; |
| 411 | struct file *fp; |
| 412 | struct filedesc *fdp; |
| 413 | struct uio auio; |
| 414 | struct iovec *iov; |
| 415 | struct iovec *needfree; |
| 416 | struct iovec aiov[UIO_SMALLIOV]; |
| 417 | long i, cnt, error = 0; |
| 418 | u_int iovlen; |
| 419 | #ifdef KTRACE |
| 420 | struct iovec *ktriov = NULL; |
| 421 | struct uio ktruio; |
| 422 | #endif |
| 423 | |
| 424 | KKASSERT(p); |
| 425 | fdp = p->p_fd; |
| 426 | |
| 427 | if ((fp = holdfp(fdp, uap->fd, FWRITE)) == NULL) |
| 428 | return (EBADF); |
| 429 | /* note: can't use iovlen until iovcnt is validated */ |
| 430 | iovlen = uap->iovcnt * sizeof (struct iovec); |
| 431 | if (uap->iovcnt > UIO_SMALLIOV) { |
| 432 | if (uap->iovcnt > UIO_MAXIOV) { |
| 433 | needfree = NULL; |
| 434 | error = EINVAL; |
| 435 | goto done; |
| 436 | } |
| 437 | MALLOC(iov, struct iovec *, iovlen, M_IOV, M_WAITOK); |
| 438 | needfree = iov; |
| 439 | } else { |
| 440 | iov = aiov; |
| 441 | needfree = NULL; |
| 442 | } |
| 443 | auio.uio_iov = iov; |
| 444 | auio.uio_iovcnt = uap->iovcnt; |
| 445 | auio.uio_rw = UIO_WRITE; |
| 446 | auio.uio_segflg = UIO_USERSPACE; |
| 447 | auio.uio_td = td; |
| 448 | auio.uio_offset = -1; |
| 449 | if ((error = copyin((caddr_t)uap->iovp, (caddr_t)iov, iovlen))) |
| 450 | goto done; |
| 451 | auio.uio_resid = 0; |
| 452 | for (i = 0; i < uap->iovcnt; i++) { |
| 453 | if (iov->iov_len > INT_MAX - auio.uio_resid) { |
| 454 | error = EINVAL; |
| 455 | goto done; |
| 456 | } |
| 457 | auio.uio_resid += iov->iov_len; |
| 458 | iov++; |
| 459 | } |
| 460 | #ifdef KTRACE |
| 461 | /* |
| 462 | * if tracing, save a copy of iovec and uio |
| 463 | */ |
| 464 | if (KTRPOINT(td, KTR_GENIO)) { |
| 465 | MALLOC(ktriov, struct iovec *, iovlen, M_TEMP, M_WAITOK); |
| 466 | bcopy((caddr_t)auio.uio_iov, (caddr_t)ktriov, iovlen); |
| 467 | ktruio = auio; |
| 468 | } |
| 469 | #endif |
| 470 | cnt = auio.uio_resid; |
| 471 | if (fp->f_type == DTYPE_VNODE) |
| 472 | bwillwrite(); |
| 473 | if ((error = fo_write(fp, &auio, fp->f_cred, 0, td))) { |
| 474 | if (auio.uio_resid != cnt && (error == ERESTART || |
| 475 | error == EINTR || error == EWOULDBLOCK)) |
| 476 | error = 0; |
| 477 | if (error == EPIPE) |
| 478 | psignal(p, SIGPIPE); |
| 479 | } |
| 480 | cnt -= auio.uio_resid; |
| 481 | #ifdef KTRACE |
| 482 | if (ktriov != NULL) { |
| 483 | if (error == 0) { |
| 484 | ktruio.uio_iov = ktriov; |
| 485 | ktruio.uio_resid = cnt; |
| 486 | ktrgenio(p->p_tracep, uap->fd, UIO_WRITE, &ktruio, |
| 487 | error); |
| 488 | } |
| 489 | FREE(ktriov, M_TEMP); |
| 490 | } |
| 491 | #endif |
| 492 | uap->lmsg.u.ms_result = cnt; |
| 493 | done: |
| 494 | fdrop(fp, td); |
| 495 | if (needfree) |
| 496 | FREE(needfree, M_IOV); |
| 497 | return (error); |
| 498 | } |
| 499 | |
| 500 | /* |
| 501 | * Ioctl system call |
| 502 | */ |
| 503 | /* ARGSUSED */ |
| 504 | int |
| 505 | ioctl(struct ioctl_args *uap) |
| 506 | { |
| 507 | struct thread *td = curthread; |
| 508 | struct proc *p = td->td_proc; |
| 509 | struct file *fp; |
| 510 | struct filedesc *fdp; |
| 511 | u_long com; |
| 512 | int error; |
| 513 | u_int size; |
| 514 | caddr_t data, memp; |
| 515 | int tmp; |
| 516 | #define STK_PARAMS 128 |
| 517 | union { |
| 518 | char stkbuf[STK_PARAMS]; |
| 519 | long align; |
| 520 | } ubuf; |
| 521 | |
| 522 | KKASSERT(p); |
| 523 | fdp = p->p_fd; |
| 524 | if ((u_int)uap->fd >= fdp->fd_nfiles || |
| 525 | (fp = fdp->fd_ofiles[uap->fd]) == NULL) |
| 526 | return (EBADF); |
| 527 | |
| 528 | if ((fp->f_flag & (FREAD | FWRITE)) == 0) |
| 529 | return (EBADF); |
| 530 | |
| 531 | switch (com = uap->com) { |
| 532 | case FIONCLEX: |
| 533 | fdp->fd_ofileflags[uap->fd] &= ~UF_EXCLOSE; |
| 534 | return (0); |
| 535 | case FIOCLEX: |
| 536 | fdp->fd_ofileflags[uap->fd] |= UF_EXCLOSE; |
| 537 | return (0); |
| 538 | } |
| 539 | |
| 540 | /* |
| 541 | * Interpret high order word to find amount of data to be |
| 542 | * copied to/from the user's address space. |
| 543 | */ |
| 544 | size = IOCPARM_LEN(com); |
| 545 | if (size > IOCPARM_MAX) |
| 546 | return (ENOTTY); |
| 547 | |
| 548 | fhold(fp); |
| 549 | |
| 550 | memp = NULL; |
| 551 | if (size > sizeof (ubuf.stkbuf)) { |
| 552 | memp = (caddr_t)malloc((u_long)size, M_IOCTLOPS, M_WAITOK); |
| 553 | data = memp; |
| 554 | } else { |
| 555 | data = ubuf.stkbuf; |
| 556 | } |
| 557 | if (com&IOC_IN) { |
| 558 | if (size) { |
| 559 | error = copyin(uap->data, data, (u_int)size); |
| 560 | if (error) { |
| 561 | if (memp) |
| 562 | free(memp, M_IOCTLOPS); |
| 563 | fdrop(fp, td); |
| 564 | return (error); |
| 565 | } |
| 566 | } else { |
| 567 | *(caddr_t *)data = uap->data; |
| 568 | } |
| 569 | } else if ((com&IOC_OUT) && size) { |
| 570 | /* |
| 571 | * Zero the buffer so the user always |
| 572 | * gets back something deterministic. |
| 573 | */ |
| 574 | bzero(data, size); |
| 575 | } else if (com&IOC_VOID) { |
| 576 | *(caddr_t *)data = uap->data; |
| 577 | } |
| 578 | |
| 579 | switch (com) { |
| 580 | |
| 581 | case FIONBIO: |
| 582 | if ((tmp = *(int *)data)) |
| 583 | fp->f_flag |= FNONBLOCK; |
| 584 | else |
| 585 | fp->f_flag &= ~FNONBLOCK; |
| 586 | error = fo_ioctl(fp, FIONBIO, (caddr_t)&tmp, td); |
| 587 | break; |
| 588 | |
| 589 | case FIOASYNC: |
| 590 | if ((tmp = *(int *)data)) |
| 591 | fp->f_flag |= FASYNC; |
| 592 | else |
| 593 | fp->f_flag &= ~FASYNC; |
| 594 | error = fo_ioctl(fp, FIOASYNC, (caddr_t)&tmp, td); |
| 595 | break; |
| 596 | |
| 597 | default: |
| 598 | error = fo_ioctl(fp, com, data, td); |
| 599 | /* |
| 600 | * Copy any data to user, size was |
| 601 | * already set and checked above. |
| 602 | */ |
| 603 | if (error == 0 && (com&IOC_OUT) && size) |
| 604 | error = copyout(data, uap->data, (u_int)size); |
| 605 | break; |
| 606 | } |
| 607 | if (memp) |
| 608 | free(memp, M_IOCTLOPS); |
| 609 | fdrop(fp, td); |
| 610 | return (error); |
| 611 | } |
| 612 | |
| 613 | static int nselcoll; /* Select collisions since boot */ |
| 614 | int selwait; |
| 615 | SYSCTL_INT(_kern, OID_AUTO, nselcoll, CTLFLAG_RD, &nselcoll, 0, ""); |
| 616 | |
| 617 | /* |
| 618 | * Select system call. |
| 619 | */ |
| 620 | int |
| 621 | select(struct select_args *uap) |
| 622 | { |
| 623 | struct proc *p = curproc; |
| 624 | |
| 625 | /* |
| 626 | * The magic 2048 here is chosen to be just enough for FD_SETSIZE |
| 627 | * infds with the new FD_SETSIZE of 1024, and more than enough for |
| 628 | * FD_SETSIZE infds, outfds and exceptfds with the old FD_SETSIZE |
| 629 | * of 256. |
| 630 | */ |
| 631 | fd_mask s_selbits[howmany(2048, NFDBITS)]; |
| 632 | fd_mask *ibits[3], *obits[3], *selbits, *sbp; |
| 633 | struct timeval atv, rtv, ttv; |
| 634 | int s, ncoll, error, timo; |
| 635 | u_int nbufbytes, ncpbytes, nfdbits; |
| 636 | |
| 637 | if (uap->nd < 0) |
| 638 | return (EINVAL); |
| 639 | if (uap->nd > p->p_fd->fd_nfiles) |
| 640 | uap->nd = p->p_fd->fd_nfiles; /* forgiving; slightly wrong */ |
| 641 | |
| 642 | /* |
| 643 | * Allocate just enough bits for the non-null fd_sets. Use the |
| 644 | * preallocated auto buffer if possible. |
| 645 | */ |
| 646 | nfdbits = roundup(uap->nd, NFDBITS); |
| 647 | ncpbytes = nfdbits / NBBY; |
| 648 | nbufbytes = 0; |
| 649 | if (uap->in != NULL) |
| 650 | nbufbytes += 2 * ncpbytes; |
| 651 | if (uap->ou != NULL) |
| 652 | nbufbytes += 2 * ncpbytes; |
| 653 | if (uap->ex != NULL) |
| 654 | nbufbytes += 2 * ncpbytes; |
| 655 | if (nbufbytes <= sizeof s_selbits) |
| 656 | selbits = &s_selbits[0]; |
| 657 | else |
| 658 | selbits = malloc(nbufbytes, M_SELECT, M_WAITOK); |
| 659 | |
| 660 | /* |
| 661 | * Assign pointers into the bit buffers and fetch the input bits. |
| 662 | * Put the output buffers together so that they can be bzeroed |
| 663 | * together. |
| 664 | */ |
| 665 | sbp = selbits; |
| 666 | #define getbits(name, x) \ |
| 667 | do { \ |
| 668 | if (uap->name == NULL) \ |
| 669 | ibits[x] = NULL; \ |
| 670 | else { \ |
| 671 | ibits[x] = sbp + nbufbytes / 2 / sizeof *sbp; \ |
| 672 | obits[x] = sbp; \ |
| 673 | sbp += ncpbytes / sizeof *sbp; \ |
| 674 | error = copyin(uap->name, ibits[x], ncpbytes); \ |
| 675 | if (error != 0) \ |
| 676 | goto done; \ |
| 677 | } \ |
| 678 | } while (0) |
| 679 | getbits(in, 0); |
| 680 | getbits(ou, 1); |
| 681 | getbits(ex, 2); |
| 682 | #undef getbits |
| 683 | if (nbufbytes != 0) |
| 684 | bzero(selbits, nbufbytes / 2); |
| 685 | |
| 686 | if (uap->tv) { |
| 687 | error = copyin((caddr_t)uap->tv, (caddr_t)&atv, |
| 688 | sizeof (atv)); |
| 689 | if (error) |
| 690 | goto done; |
| 691 | if (itimerfix(&atv)) { |
| 692 | error = EINVAL; |
| 693 | goto done; |
| 694 | } |
| 695 | getmicrouptime(&rtv); |
| 696 | timevaladd(&atv, &rtv); |
| 697 | } else { |
| 698 | atv.tv_sec = 0; |
| 699 | atv.tv_usec = 0; |
| 700 | } |
| 701 | timo = 0; |
| 702 | retry: |
| 703 | ncoll = nselcoll; |
| 704 | p->p_flag |= P_SELECT; |
| 705 | error = selscan(p, ibits, obits, uap->nd, &uap->lmsg.u.ms_result); |
| 706 | if (error || uap->lmsg.u.ms_result) |
| 707 | goto done; |
| 708 | if (atv.tv_sec || atv.tv_usec) { |
| 709 | getmicrouptime(&rtv); |
| 710 | if (timevalcmp(&rtv, &atv, >=)) |
| 711 | goto done; |
| 712 | ttv = atv; |
| 713 | timevalsub(&ttv, &rtv); |
| 714 | timo = ttv.tv_sec > 24 * 60 * 60 ? |
| 715 | 24 * 60 * 60 * hz : tvtohz(&ttv); |
| 716 | } |
| 717 | s = splhigh(); |
| 718 | if ((p->p_flag & P_SELECT) == 0 || nselcoll != ncoll) { |
| 719 | splx(s); |
| 720 | goto retry; |
| 721 | } |
| 722 | p->p_flag &= ~P_SELECT; |
| 723 | |
| 724 | error = tsleep((caddr_t)&selwait, PCATCH, "select", timo); |
| 725 | |
| 726 | splx(s); |
| 727 | if (error == 0) |
| 728 | goto retry; |
| 729 | done: |
| 730 | p->p_flag &= ~P_SELECT; |
| 731 | /* select is not restarted after signals... */ |
| 732 | if (error == ERESTART) |
| 733 | error = EINTR; |
| 734 | if (error == EWOULDBLOCK) |
| 735 | error = 0; |
| 736 | #define putbits(name, x) \ |
| 737 | if (uap->name && (error2 = copyout(obits[x], uap->name, ncpbytes))) \ |
| 738 | error = error2; |
| 739 | if (error == 0) { |
| 740 | int error2; |
| 741 | |
| 742 | putbits(in, 0); |
| 743 | putbits(ou, 1); |
| 744 | putbits(ex, 2); |
| 745 | #undef putbits |
| 746 | } |
| 747 | if (selbits != &s_selbits[0]) |
| 748 | free(selbits, M_SELECT); |
| 749 | return (error); |
| 750 | } |
| 751 | |
| 752 | static int |
| 753 | selscan(struct proc *p, fd_mask **ibits, fd_mask **obits, int nfd, int *res) |
| 754 | { |
| 755 | struct thread *td = p->p_thread; |
| 756 | struct filedesc *fdp = p->p_fd; |
| 757 | int msk, i, fd; |
| 758 | fd_mask bits; |
| 759 | struct file *fp; |
| 760 | int n = 0; |
| 761 | /* Note: backend also returns POLLHUP/POLLERR if appropriate. */ |
| 762 | static int flag[3] = { POLLRDNORM, POLLWRNORM, POLLRDBAND }; |
| 763 | |
| 764 | for (msk = 0; msk < 3; msk++) { |
| 765 | if (ibits[msk] == NULL) |
| 766 | continue; |
| 767 | for (i = 0; i < nfd; i += NFDBITS) { |
| 768 | bits = ibits[msk][i/NFDBITS]; |
| 769 | /* ffs(int mask) not portable, fd_mask is long */ |
| 770 | for (fd = i; bits && fd < nfd; fd++, bits >>= 1) { |
| 771 | if (!(bits & 1)) |
| 772 | continue; |
| 773 | fp = fdp->fd_ofiles[fd]; |
| 774 | if (fp == NULL) |
| 775 | return (EBADF); |
| 776 | if (fo_poll(fp, flag[msk], fp->f_cred, td)) { |
| 777 | obits[msk][(fd)/NFDBITS] |= |
| 778 | ((fd_mask)1 << ((fd) % NFDBITS)); |
| 779 | n++; |
| 780 | } |
| 781 | } |
| 782 | } |
| 783 | } |
| 784 | *res = n; |
| 785 | return (0); |
| 786 | } |
| 787 | |
| 788 | /* |
| 789 | * Poll system call. |
| 790 | */ |
| 791 | int |
| 792 | poll(struct poll_args *uap) |
| 793 | { |
| 794 | caddr_t bits; |
| 795 | char smallbits[32 * sizeof(struct pollfd)]; |
| 796 | struct timeval atv, rtv, ttv; |
| 797 | int s, ncoll, error = 0, timo; |
| 798 | u_int nfds; |
| 799 | size_t ni; |
| 800 | struct proc *p = curproc; |
| 801 | |
| 802 | nfds = SCARG(uap, nfds); |
| 803 | /* |
| 804 | * This is kinda bogus. We have fd limits, but that is not |
| 805 | * really related to the size of the pollfd array. Make sure |
| 806 | * we let the process use at least FD_SETSIZE entries and at |
| 807 | * least enough for the current limits. We want to be reasonably |
| 808 | * safe, but not overly restrictive. |
| 809 | */ |
| 810 | if (nfds > p->p_rlimit[RLIMIT_NOFILE].rlim_cur && nfds > FD_SETSIZE) |
| 811 | return (EINVAL); |
| 812 | ni = nfds * sizeof(struct pollfd); |
| 813 | if (ni > sizeof(smallbits)) |
| 814 | bits = malloc(ni, M_TEMP, M_WAITOK); |
| 815 | else |
| 816 | bits = smallbits; |
| 817 | error = copyin(SCARG(uap, fds), bits, ni); |
| 818 | if (error) |
| 819 | goto done; |
| 820 | if (SCARG(uap, timeout) != INFTIM) { |
| 821 | atv.tv_sec = SCARG(uap, timeout) / 1000; |
| 822 | atv.tv_usec = (SCARG(uap, timeout) % 1000) * 1000; |
| 823 | if (itimerfix(&atv)) { |
| 824 | error = EINVAL; |
| 825 | goto done; |
| 826 | } |
| 827 | getmicrouptime(&rtv); |
| 828 | timevaladd(&atv, &rtv); |
| 829 | } else { |
| 830 | atv.tv_sec = 0; |
| 831 | atv.tv_usec = 0; |
| 832 | } |
| 833 | timo = 0; |
| 834 | retry: |
| 835 | ncoll = nselcoll; |
| 836 | p->p_flag |= P_SELECT; |
| 837 | error = pollscan(p, (struct pollfd *)bits, nfds, &uap->lmsg.u.ms_result); |
| 838 | if (error || uap->lmsg.u.ms_result) |
| 839 | goto done; |
| 840 | if (atv.tv_sec || atv.tv_usec) { |
| 841 | getmicrouptime(&rtv); |
| 842 | if (timevalcmp(&rtv, &atv, >=)) |
| 843 | goto done; |
| 844 | ttv = atv; |
| 845 | timevalsub(&ttv, &rtv); |
| 846 | timo = ttv.tv_sec > 24 * 60 * 60 ? |
| 847 | 24 * 60 * 60 * hz : tvtohz(&ttv); |
| 848 | } |
| 849 | s = splhigh(); |
| 850 | if ((p->p_flag & P_SELECT) == 0 || nselcoll != ncoll) { |
| 851 | splx(s); |
| 852 | goto retry; |
| 853 | } |
| 854 | p->p_flag &= ~P_SELECT; |
| 855 | error = tsleep((caddr_t)&selwait, PCATCH, "poll", timo); |
| 856 | splx(s); |
| 857 | if (error == 0) |
| 858 | goto retry; |
| 859 | done: |
| 860 | p->p_flag &= ~P_SELECT; |
| 861 | /* poll is not restarted after signals... */ |
| 862 | if (error == ERESTART) |
| 863 | error = EINTR; |
| 864 | if (error == EWOULDBLOCK) |
| 865 | error = 0; |
| 866 | if (error == 0) { |
| 867 | error = copyout(bits, SCARG(uap, fds), ni); |
| 868 | if (error) |
| 869 | goto out; |
| 870 | } |
| 871 | out: |
| 872 | if (ni > sizeof(smallbits)) |
| 873 | free(bits, M_TEMP); |
| 874 | return (error); |
| 875 | } |
| 876 | |
| 877 | static int |
| 878 | pollscan(struct proc *p, struct pollfd *fds, u_int nfd, int *res) |
| 879 | { |
| 880 | struct thread *td = p->p_thread; |
| 881 | struct filedesc *fdp = p->p_fd; |
| 882 | int i; |
| 883 | struct file *fp; |
| 884 | int n = 0; |
| 885 | |
| 886 | for (i = 0; i < nfd; i++, fds++) { |
| 887 | if (fds->fd >= fdp->fd_nfiles) { |
| 888 | fds->revents = POLLNVAL; |
| 889 | n++; |
| 890 | } else if (fds->fd < 0) { |
| 891 | fds->revents = 0; |
| 892 | } else { |
| 893 | fp = fdp->fd_ofiles[fds->fd]; |
| 894 | if (fp == NULL) { |
| 895 | fds->revents = POLLNVAL; |
| 896 | n++; |
| 897 | } else { |
| 898 | /* |
| 899 | * Note: backend also returns POLLHUP and |
| 900 | * POLLERR if appropriate. |
| 901 | */ |
| 902 | fds->revents = fo_poll(fp, fds->events, |
| 903 | fp->f_cred, td); |
| 904 | if (fds->revents != 0) |
| 905 | n++; |
| 906 | } |
| 907 | } |
| 908 | } |
| 909 | *res = n; |
| 910 | return (0); |
| 911 | } |
| 912 | |
| 913 | /* |
| 914 | * OpenBSD poll system call. |
| 915 | * XXX this isn't quite a true representation.. OpenBSD uses select ops. |
| 916 | */ |
| 917 | int |
| 918 | openbsd_poll(struct openbsd_poll_args *uap) |
| 919 | { |
| 920 | return (poll((struct poll_args *)uap)); |
| 921 | } |
| 922 | |
| 923 | /*ARGSUSED*/ |
| 924 | int |
| 925 | seltrue(dev_t dev, int events, struct thread *td) |
| 926 | { |
| 927 | return (events & (POLLIN | POLLOUT | POLLRDNORM | POLLWRNORM)); |
| 928 | } |
| 929 | |
| 930 | /* |
| 931 | * Record a select request. A global wait must be used since a process/thread |
| 932 | * might go away after recording its request. |
| 933 | */ |
| 934 | void |
| 935 | selrecord(struct thread *selector, struct selinfo *sip) |
| 936 | { |
| 937 | struct proc *p; |
| 938 | pid_t mypid; |
| 939 | |
| 940 | if ((p = selector->td_proc) == NULL) |
| 941 | panic("selrecord: thread needs a process"); |
| 942 | |
| 943 | mypid = p->p_pid; |
| 944 | if (sip->si_pid == mypid) |
| 945 | return; |
| 946 | if (sip->si_pid && (p = pfind(sip->si_pid)) && |
| 947 | p->p_wchan == (caddr_t)&selwait) { |
| 948 | sip->si_flags |= SI_COLL; |
| 949 | } else { |
| 950 | sip->si_pid = mypid; |
| 951 | } |
| 952 | } |
| 953 | |
| 954 | /* |
| 955 | * Do a wakeup when a selectable event occurs. |
| 956 | */ |
| 957 | void |
| 958 | selwakeup(struct selinfo *sip) |
| 959 | { |
| 960 | struct proc *p; |
| 961 | int s; |
| 962 | |
| 963 | if (sip->si_pid == 0) |
| 964 | return; |
| 965 | if (sip->si_flags & SI_COLL) { |
| 966 | nselcoll++; |
| 967 | sip->si_flags &= ~SI_COLL; |
| 968 | wakeup((caddr_t)&selwait); /* YYY fixable */ |
| 969 | } |
| 970 | p = pfind(sip->si_pid); |
| 971 | sip->si_pid = 0; |
| 972 | if (p != NULL) { |
| 973 | s = splhigh(); |
| 974 | if (p->p_wchan == (caddr_t)&selwait) { |
| 975 | if (p->p_stat == SSLEEP) |
| 976 | setrunnable(p); |
| 977 | else |
| 978 | unsleep(p->p_thread); |
| 979 | } else if (p->p_flag & P_SELECT) |
| 980 | p->p_flag &= ~P_SELECT; |
| 981 | splx(s); |
| 982 | } |
| 983 | } |
| 984 | |