/* $NetBSD: sys_descrip.c,v 1.33.2.1 2024/11/20 14:01:59 martin Exp $ */ /*- * Copyright (c) 2008 The NetBSD Foundation, Inc. * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE * POSSIBILITY OF SUCH DAMAGE. */ /* * Copyright (c) 1982, 1986, 1989, 1991, 1993 * The Regents of the University of California. All rights reserved. * (c) UNIX System Laboratories, Inc. * All or some portions of this file are derived from material licensed * to the University of California by American Telephone and Telegraph * Co. or Unix System Laboratories, Inc. and are reproduced herein with * the permission of UNIX System Laboratories, Inc. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * @(#)kern_descrip.c 8.8 (Berkeley) 2/14/95 */ /* * System calls on descriptors. */ #include __KERNEL_RCSID(0, "$NetBSD: sys_descrip.c,v 1.33.2.1 2024/11/20 14:01:59 martin Exp $"); #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include /* * Duplicate a file descriptor. */ int sys_dup(struct lwp *l, const struct sys_dup_args *uap, register_t *retval) { /* { syscallarg(int) fd; } */ int error, newfd, oldfd; file_t *fp; oldfd = SCARG(uap, fd); if ((fp = fd_getfile(oldfd)) == NULL) { return EBADF; } error = fd_dup(fp, 0, &newfd, false); fd_putfile(oldfd); *retval = newfd; return error; } /* * Duplicate a file descriptor to a particular value. */ int dodup(struct lwp *l, int from, int to, int flags, register_t *retval) { int error; file_t *fp; if ((fp = fd_getfile(from)) == NULL) return EBADF; mutex_enter(&fp->f_lock); fp->f_count++; mutex_exit(&fp->f_lock); fd_putfile(from); if ((u_int)to >= curproc->p_rlimit[RLIMIT_NOFILE].rlim_cur || (u_int)to >= maxfiles) error = EBADF; else if (from == to) error = 0; else error = fd_dup2(fp, to, flags); closef(fp); *retval = to; return error; } int sys_dup3(struct lwp *l, const struct sys_dup3_args *uap, register_t *retval) { /* { syscallarg(int) from; syscallarg(int) to; syscallarg(int) flags; } */ return dodup(l, SCARG(uap, from), SCARG(uap, to), SCARG(uap, flags), retval); } int sys_dup2(struct lwp *l, const struct sys_dup2_args *uap, register_t *retval) { /* { syscallarg(int) from; syscallarg(int) to; } */ return dodup(l, SCARG(uap, from), SCARG(uap, to), 0, retval); } /* * fcntl call which is being passed to the file's fs. */ static int fcntl_forfs(int fd, file_t *fp, int cmd, void *arg) { int error; u_int size; void *data, *memp; #define STK_PARAMS 128 char stkbuf[STK_PARAMS]; if ((fp->f_flag & (FREAD | FWRITE)) == 0) return (EBADF); /* * Interpret high order word to find amount of data to be * copied to/from the user's address space. */ size = (size_t)F_PARAM_LEN(cmd); if (size > F_PARAM_MAX) return (EINVAL); memp = NULL; if (size > sizeof(stkbuf)) { memp = kmem_alloc(size, KM_SLEEP); data = memp; } else data = stkbuf; if (cmd & F_FSIN) { if (size) { error = copyin(arg, data, size); if (error) { if (memp) kmem_free(memp, size); return (error); } } else *(void **)data = arg; } else if ((cmd & F_FSOUT) != 0 && size != 0) { /* * Zero the buffer so the user always * gets back something deterministic. */ memset(data, 0, size); } else if (cmd & F_FSVOID) *(void **)data = arg; error = (*fp->f_ops->fo_fcntl)(fp, cmd, data); /* * Copy any data to user, size was * already set and checked above. */ if (error == 0 && (cmd & F_FSOUT) && size) error = copyout(data, arg, size); if (memp) kmem_free(memp, size); return (error); } int do_fcntl_lock(int fd, int cmd, struct flock *fl) { file_t *fp; vnode_t *vp; proc_t *p; int error, flg; if ((fp = fd_getfile(fd)) == NULL) return EBADF; if (fp->f_type != DTYPE_VNODE) { fd_putfile(fd); return EINVAL; } vp = fp->f_vnode; if (fl->l_whence == SEEK_CUR) fl->l_start += fp->f_offset; flg = F_POSIX; p = curproc; switch (cmd) { case F_SETLKW: flg |= F_WAIT; /* Fall into F_SETLK */ /* FALLTHROUGH */ case F_SETLK: switch (fl->l_type) { case F_RDLCK: if ((fp->f_flag & FREAD) == 0) { error = EBADF; break; } if ((p->p_flag & PK_ADVLOCK) == 0) { mutex_enter(p->p_lock); p->p_flag |= PK_ADVLOCK; mutex_exit(p->p_lock); } error = VOP_ADVLOCK(vp, p, F_SETLK, fl, flg); break; case F_WRLCK: if ((fp->f_flag & FWRITE) == 0) { error = EBADF; break; } if ((p->p_flag & PK_ADVLOCK) == 0) { mutex_enter(p->p_lock); p->p_flag |= PK_ADVLOCK; mutex_exit(p->p_lock); } error = VOP_ADVLOCK(vp, p, F_SETLK, fl, flg); break; case F_UNLCK: error = VOP_ADVLOCK(vp, p, F_UNLCK, fl, F_POSIX); break; default: error = EINVAL; break; } break; case F_GETLK: if (fl->l_type != F_RDLCK && fl->l_type != F_WRLCK && fl->l_type != F_UNLCK) { error = EINVAL; break; } error = VOP_ADVLOCK(vp, p, F_GETLK, fl, F_POSIX); break; default: error = EINVAL; break; } fd_putfile(fd); return error; } /* * The file control system call. */ int sys_fcntl(struct lwp *l, const struct sys_fcntl_args *uap, register_t *retval) { /* { syscallarg(int) fd; syscallarg(int) cmd; syscallarg(void *) arg; } */ int fd, i, tmp, error, cmd, newmin; filedesc_t *fdp; fdtab_t *dt; file_t *fp; struct flock fl; bool cloexec = false; fd = SCARG(uap, fd); cmd = SCARG(uap, cmd); fdp = l->l_fd; error = 0; switch (cmd) { case F_CLOSEM: if (fd < 0) return EBADF; while ((i = fdp->fd_lastfile) >= fd) { if (fd_getfile(i) == NULL) { /* Another thread has updated. */ continue; } fd_close(i); } return 0; case F_MAXFD: *retval = fdp->fd_lastfile; return 0; case F_SETLKW: case F_SETLK: case F_GETLK: error = copyin(SCARG(uap, arg), &fl, sizeof(fl)); if (error) return error; error = do_fcntl_lock(fd, cmd, &fl); if (cmd == F_GETLK && error == 0) error = copyout(&fl, SCARG(uap, arg), sizeof(fl)); return error; default: /* Handled below */ break; } if ((fp = fd_getfile(fd)) == NULL) return (EBADF); if ((cmd & F_FSCTL)) { error = fcntl_forfs(fd, fp, cmd, SCARG(uap, arg)); fd_putfile(fd); return error; } switch (cmd) { case F_DUPFD_CLOEXEC: cloexec = true; /*FALLTHROUGH*/ case F_DUPFD: newmin = (long)SCARG(uap, arg); if ((u_int)newmin >= l->l_proc->p_rlimit[RLIMIT_NOFILE].rlim_cur || (u_int)newmin >= maxfiles) { fd_putfile(fd); return EINVAL; } error = fd_dup(fp, newmin, &i, cloexec); *retval = i; break; case F_GETFD: dt = atomic_load_consume(&fdp->fd_dt); *retval = dt->dt_ff[fd]->ff_exclose; break; case F_SETFD: fd_set_exclose(l, fd, ((long)SCARG(uap, arg) & FD_CLOEXEC) != 0); break; case F_GETNOSIGPIPE: *retval = (fp->f_flag & FNOSIGPIPE) != 0; break; case F_SETNOSIGPIPE: if (SCARG(uap, arg)) atomic_or_uint(&fp->f_flag, FNOSIGPIPE); else atomic_and_uint(&fp->f_flag, ~FNOSIGPIPE); *retval = 0; break; case F_GETFL: *retval = OFLAGS(fp->f_flag); break; case F_SETFL: /* XXX not guaranteed to be atomic. */ tmp = FFLAGS((long)SCARG(uap, arg)) & FCNTLFLAGS; error = (*fp->f_ops->fo_fcntl)(fp, F_SETFL, &tmp); if (error) break; i = tmp ^ fp->f_flag; if (i & FNONBLOCK) { int flgs = tmp & FNONBLOCK; error = (*fp->f_ops->fo_ioctl)(fp, FIONBIO, &flgs); if (error) { (*fp->f_ops->fo_fcntl)(fp, F_SETFL, &fp->f_flag); break; } } if (i & FASYNC) { int flgs = tmp & FASYNC; error = (*fp->f_ops->fo_ioctl)(fp, FIOASYNC, &flgs); if (error) { if (i & FNONBLOCK) { tmp = fp->f_flag & FNONBLOCK; (void)(*fp->f_ops->fo_ioctl)(fp, FIONBIO, &tmp); } (*fp->f_ops->fo_fcntl)(fp, F_SETFL, &fp->f_flag); break; } } fp->f_flag = (fp->f_flag & ~FCNTLFLAGS) | tmp; break; case F_GETOWN: error = (*fp->f_ops->fo_ioctl)(fp, FIOGETOWN, &tmp); *retval = tmp; break; case F_SETOWN: tmp = (int)(uintptr_t) SCARG(uap, arg); error = (*fp->f_ops->fo_ioctl)(fp, FIOSETOWN, &tmp); break; default: error = EINVAL; } fd_putfile(fd); return (error); } /* * Close a file descriptor. */ int sys_close(struct lwp *l, const struct sys_close_args *uap, register_t *retval) { /* { syscallarg(int) fd; } */ int error; int fd = SCARG(uap, fd); if (fd_getfile(fd) == NULL) { return EBADF; } error = fd_close(fd); if (error == ERESTART) { #ifdef DIAGNOSTIC printf("%s[%d]: close(%d) returned ERESTART\n", l->l_proc->p_comm, (int)l->l_proc->p_pid, fd); #endif error = EINTR; } return error; } /* * Return status information about a file descriptor. * Common function for compat code. */ int do_sys_fstat(int fd, struct stat *sb) { file_t *fp; int error; if ((fp = fd_getfile(fd)) == NULL) { return EBADF; } error = (*fp->f_ops->fo_stat)(fp, sb); fd_putfile(fd); return error; } /* * Return status information about a file descriptor. */ int sys___fstat50(struct lwp *l, const struct sys___fstat50_args *uap, register_t *retval) { /* { syscallarg(int) fd; syscallarg(struct stat *) sb; } */ struct stat sb; int error; error = do_sys_fstat(SCARG(uap, fd), &sb); if (error == 0) { error = copyout(&sb, SCARG(uap, sb), sizeof(sb)); } return error; } /* * Return pathconf information about a file descriptor. */ int sys_fpathconf(struct lwp *l, const struct sys_fpathconf_args *uap, register_t *retval) { /* { syscallarg(int) fd; syscallarg(int) name; } */ int fd, error; file_t *fp; fd = SCARG(uap, fd); error = 0; if ((fp = fd_getfile(fd)) == NULL) { return (EBADF); } switch (fp->f_type) { case DTYPE_SOCKET: case DTYPE_PIPE: if (SCARG(uap, name) != _PC_PIPE_BUF) error = EINVAL; else *retval = PIPE_BUF; break; case DTYPE_VNODE: error = VOP_PATHCONF(fp->f_vnode, SCARG(uap, name), retval); break; case DTYPE_KQUEUE: error = EINVAL; break; default: error = EOPNOTSUPP; break; } fd_putfile(fd); return (error); } /* * Apply an advisory lock on a file descriptor. * * Just attempt to get a record lock of the requested type on * the entire file (l_whence = SEEK_SET, l_start = 0, l_len = 0). */ /* ARGSUSED */ int sys_flock(struct lwp *l, const struct sys_flock_args *uap, register_t *retval) { /* { syscallarg(int) fd; syscallarg(int) how; } */ int fd, how, error; file_t *fp; vnode_t *vp; struct flock lf; fd = SCARG(uap, fd); how = SCARG(uap, how); error = 0; if ((fp = fd_getfile(fd)) == NULL) { return EBADF; } if (fp->f_type != DTYPE_VNODE) { fd_putfile(fd); return EOPNOTSUPP; } vp = fp->f_vnode; lf.l_whence = SEEK_SET; lf.l_start = 0; lf.l_len = 0; switch (how & ~LOCK_NB) { case LOCK_UN: lf.l_type = F_UNLCK; atomic_and_uint(&fp->f_flag, ~FHASLOCK); error = VOP_ADVLOCK(vp, fp, F_UNLCK, &lf, F_FLOCK); fd_putfile(fd); return error; case LOCK_EX: lf.l_type = F_WRLCK; break; case LOCK_SH: lf.l_type = F_RDLCK; break; default: fd_putfile(fd); return EINVAL; } atomic_or_uint(&fp->f_flag, FHASLOCK); if (how & LOCK_NB) { error = VOP_ADVLOCK(vp, fp, F_SETLK, &lf, F_FLOCK); } else { error = VOP_ADVLOCK(vp, fp, F_SETLK, &lf, F_FLOCK|F_WAIT); } fd_putfile(fd); return error; } int do_posix_fadvise(int fd, off_t offset, off_t len, int advice) { file_t *fp; vnode_t *vp; off_t endoffset; int error; CTASSERT(POSIX_FADV_NORMAL == UVM_ADV_NORMAL); CTASSERT(POSIX_FADV_RANDOM == UVM_ADV_RANDOM); CTASSERT(POSIX_FADV_SEQUENTIAL == UVM_ADV_SEQUENTIAL); if (len == 0) { endoffset = INT64_MAX; } else if (len > 0 && (INT64_MAX - offset) >= len) { endoffset = offset + len; } else { return EINVAL; } if ((fp = fd_getfile(fd)) == NULL) { return EBADF; } if (fp->f_type != DTYPE_VNODE) { if (fp->f_type == DTYPE_PIPE || fp->f_type == DTYPE_SOCKET) { error = ESPIPE; } else { error = EOPNOTSUPP; } fd_putfile(fd); return error; } switch (advice) { case POSIX_FADV_WILLNEED: case POSIX_FADV_DONTNEED: vp = fp->f_vnode; if (vp->v_type != VREG && vp->v_type != VBLK) { fd_putfile(fd); return 0; } break; } switch (advice) { case POSIX_FADV_NORMAL: case POSIX_FADV_RANDOM: case POSIX_FADV_SEQUENTIAL: /* * We ignore offset and size. Must lock the file to * do this, as f_advice is sub-word sized. */ mutex_enter(&fp->f_lock); fp->f_advice = (u_char)advice; mutex_exit(&fp->f_lock); error = 0; break; case POSIX_FADV_WILLNEED: vp = fp->f_vnode; error = uvm_readahead(&vp->v_uobj, offset, endoffset - offset); break; case POSIX_FADV_DONTNEED: vp = fp->f_vnode; /* * Align the region to page boundaries as VOP_PUTPAGES expects * by shrinking it. We shrink instead of expand because we * do not want to deactivate cache outside of the requested * region. It means that if the specified region is smaller * than PAGE_SIZE, we do nothing. */ if (round_page(offset) < trunc_page(endoffset) && offset <= round_page(offset)) { mutex_enter(vp->v_interlock); error = VOP_PUTPAGES(vp, round_page(offset), trunc_page(endoffset), PGO_DEACTIVATE | PGO_CLEANIT); } else { error = 0; } break; case POSIX_FADV_NOREUSE: /* Not implemented yet. */ error = 0; break; default: error = EINVAL; break; } fd_putfile(fd); return error; } int sys___posix_fadvise50(struct lwp *l, const struct sys___posix_fadvise50_args *uap, register_t *retval) { /* { syscallarg(int) fd; syscallarg(int) pad; syscallarg(off_t) offset; syscallarg(off_t) len; syscallarg(int) advice; } */ *retval = do_posix_fadvise(SCARG(uap, fd), SCARG(uap, offset), SCARG(uap, len), SCARG(uap, advice)); return 0; } int sys_pipe(struct lwp *l, const void *v, register_t *retval) { int fd[2], error; if ((error = pipe1(l, fd, 0)) != 0) return error; retval[0] = fd[0]; retval[1] = fd[1]; return 0; } int sys_pipe2(struct lwp *l, const struct sys_pipe2_args *uap, register_t *retval) { /* { syscallarg(int[2]) fildes; syscallarg(int) flags; } */ int fd[2], error; if ((error = pipe1(l, fd, SCARG(uap, flags))) != 0) return error; if ((error = copyout(fd, SCARG(uap, fildes), sizeof(fd))) != 0) return error; retval[0] = 0; return 0; }