/* * Copyright (c) 1982, 1986, 1989, 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. * * @(#)sys_generic.c 8.5 (Berkeley) 1/21/94 * $FreeBSD: src/sys/kern/sys_generic.c,v 1.55.2.10 2001/03/17 10:39:32 peter Exp $ */ #include "opt_ktrace.h" #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #ifdef KTRACE #include #endif #include #include #include #include #include static MALLOC_DEFINE(M_IOCTLOPS, "ioctlops", "ioctl data buffer"); static MALLOC_DEFINE(M_IOCTLMAP, "ioctlmap", "mapped ioctl handler buffer"); static MALLOC_DEFINE(M_SELECT, "select", "select() buffer"); MALLOC_DEFINE(M_IOV, "iov", "large iov's"); typedef struct kfd_set { fd_mask fds_bits[2]; } kfd_set; enum select_copyin_states { COPYIN_READ, COPYIN_WRITE, COPYIN_EXCEPT, COPYIN_DONE }; struct select_kevent_copyin_args { kfd_set *read_set; kfd_set *write_set; kfd_set *except_set; int active_set; /* One of select_copyin_states */ struct lwp *lwp; /* Pointer to our lwp */ int num_fds; /* Number of file descriptors (syscall arg) */ int proc_fds; /* Processed fd's (wraps) */ int error; /* Returned to userland */ }; struct poll_kevent_copyin_args { struct lwp *lwp; struct pollfd *fds; int nfds; int pfds; int error; }; static struct lwkt_token mioctl_token = LWKT_TOKEN_INITIALIZER(mioctl_token); static int doselect(int nd, fd_set *in, fd_set *ou, fd_set *ex, struct timespec *ts, int *res); static int dopoll(int nfds, struct pollfd *fds, struct timespec *ts, int *res, int flags); static int dofileread(int, struct file *, struct uio *, int, size_t *); static int dofilewrite(int, struct file *, struct uio *, int, size_t *); /* * Read system call. * * MPSAFE */ int sys_read(struct read_args *uap) { struct thread *td = curthread; struct uio auio; struct iovec aiov; int error; if ((ssize_t)uap->nbyte < 0) error = EINVAL; aiov.iov_base = uap->buf; aiov.iov_len = uap->nbyte; auio.uio_iov = &aiov; auio.uio_iovcnt = 1; auio.uio_offset = -1; auio.uio_resid = uap->nbyte; auio.uio_rw = UIO_READ; auio.uio_segflg = UIO_USERSPACE; auio.uio_td = td; error = kern_preadv(uap->fd, &auio, 0, &uap->sysmsg_szresult); return(error); } /* * Positioned (Pread) read system call * * MPSAFE */ int sys_extpread(struct extpread_args *uap) { struct thread *td = curthread; struct uio auio; struct iovec aiov; int error; int flags; if ((ssize_t)uap->nbyte < 0) return(EINVAL); aiov.iov_base = uap->buf; aiov.iov_len = uap->nbyte; auio.uio_iov = &aiov; auio.uio_iovcnt = 1; auio.uio_offset = uap->offset; auio.uio_resid = uap->nbyte; auio.uio_rw = UIO_READ; auio.uio_segflg = UIO_USERSPACE; auio.uio_td = td; flags = uap->flags & O_FMASK; if (uap->offset != (off_t)-1) flags |= O_FOFFSET; error = kern_preadv(uap->fd, &auio, flags, &uap->sysmsg_szresult); return(error); } /* * Scatter read system call. * * MPSAFE */ int sys_readv(struct readv_args *uap) { struct thread *td = curthread; struct uio auio; struct iovec aiov[UIO_SMALLIOV], *iov = NULL; int error; error = iovec_copyin(uap->iovp, &iov, aiov, uap->iovcnt, &auio.uio_resid); if (error) return (error); auio.uio_iov = iov; auio.uio_iovcnt = uap->iovcnt; auio.uio_offset = -1; auio.uio_rw = UIO_READ; auio.uio_segflg = UIO_USERSPACE; auio.uio_td = td; error = kern_preadv(uap->fd, &auio, 0, &uap->sysmsg_szresult); iovec_free(&iov, aiov); return (error); } /* * Scatter positioned read system call. * * MPSAFE */ int sys_extpreadv(struct extpreadv_args *uap) { struct thread *td = curthread; struct uio auio; struct iovec aiov[UIO_SMALLIOV], *iov = NULL; int error; int flags; error = iovec_copyin(uap->iovp, &iov, aiov, uap->iovcnt, &auio.uio_resid); if (error) return (error); auio.uio_iov = iov; auio.uio_iovcnt = uap->iovcnt; auio.uio_offset = uap->offset; auio.uio_rw = UIO_READ; auio.uio_segflg = UIO_USERSPACE; auio.uio_td = td; flags = uap->flags & O_FMASK; if (uap->offset != (off_t)-1) flags |= O_FOFFSET; error = kern_preadv(uap->fd, &auio, flags, &uap->sysmsg_szresult); iovec_free(&iov, aiov); return(error); } /* * MPSAFE */ int kern_preadv(int fd, struct uio *auio, int flags, size_t *res) { struct thread *td = curthread; struct file *fp; int error; fp = holdfp(td, fd, FREAD); if (fp == NULL) return (EBADF); if (flags & O_FOFFSET && fp->f_type != DTYPE_VNODE) { error = ESPIPE; } else { error = dofileread(fd, fp, auio, flags, res); } dropfp(td, fd, fp); return(error); } /* * Common code for readv and preadv that reads data in * from a file using the passed in uio, offset, and flags. * * MPALMOSTSAFE - ktrace needs help */ static int dofileread(int fd, struct file *fp, struct uio *auio, int flags, size_t *res) { int error; size_t len; #ifdef KTRACE struct thread *td = curthread; struct iovec *ktriov = NULL; struct uio ktruio; #endif #ifdef KTRACE /* * if tracing, save a copy of iovec */ if (KTRPOINT(td, KTR_GENIO)) { int iovlen = auio->uio_iovcnt * sizeof(struct iovec); ktriov = kmalloc(iovlen, M_TEMP, M_WAITOK); bcopy((caddr_t)auio->uio_iov, (caddr_t)ktriov, iovlen); ktruio = *auio; } #endif len = auio->uio_resid; error = fo_read(fp, auio, fp->f_cred, flags); if (error) { if (auio->uio_resid != len && (error == ERESTART || error == EINTR || error == EWOULDBLOCK)) error = 0; } #ifdef KTRACE if (ktriov != NULL) { if (error == 0) { ktruio.uio_iov = ktriov; ktruio.uio_resid = len - auio->uio_resid; ktrgenio(td->td_lwp, fd, UIO_READ, &ktruio, error); } kfree(ktriov, M_TEMP); } #endif if (error == 0) *res = len - auio->uio_resid; return(error); } /* * Write system call * * MPSAFE */ int sys_write(struct write_args *uap) { struct thread *td = curthread; struct uio auio; struct iovec aiov; int error; if ((ssize_t)uap->nbyte < 0) error = EINVAL; aiov.iov_base = (void *)(uintptr_t)uap->buf; aiov.iov_len = uap->nbyte; auio.uio_iov = &aiov; auio.uio_iovcnt = 1; auio.uio_offset = -1; auio.uio_resid = uap->nbyte; auio.uio_rw = UIO_WRITE; auio.uio_segflg = UIO_USERSPACE; auio.uio_td = td; error = kern_pwritev(uap->fd, &auio, 0, &uap->sysmsg_szresult); return(error); } /* * Pwrite system call * * MPSAFE */ int sys_extpwrite(struct extpwrite_args *uap) { struct thread *td = curthread; struct uio auio; struct iovec aiov; int error; int flags; if ((ssize_t)uap->nbyte < 0) error = EINVAL; aiov.iov_base = (void *)(uintptr_t)uap->buf; aiov.iov_len = uap->nbyte; auio.uio_iov = &aiov; auio.uio_iovcnt = 1; auio.uio_offset = uap->offset; auio.uio_resid = uap->nbyte; auio.uio_rw = UIO_WRITE; auio.uio_segflg = UIO_USERSPACE; auio.uio_td = td; flags = uap->flags & O_FMASK; if (uap->offset != (off_t)-1) flags |= O_FOFFSET; error = kern_pwritev(uap->fd, &auio, flags, &uap->sysmsg_szresult); return(error); } /* * MPSAFE */ int sys_writev(struct writev_args *uap) { struct thread *td = curthread; struct uio auio; struct iovec aiov[UIO_SMALLIOV], *iov = NULL; int error; error = iovec_copyin(uap->iovp, &iov, aiov, uap->iovcnt, &auio.uio_resid); if (error) return (error); auio.uio_iov = iov; auio.uio_iovcnt = uap->iovcnt; auio.uio_offset = -1; auio.uio_rw = UIO_WRITE; auio.uio_segflg = UIO_USERSPACE; auio.uio_td = td; error = kern_pwritev(uap->fd, &auio, 0, &uap->sysmsg_szresult); iovec_free(&iov, aiov); return (error); } /* * Gather positioned write system call * * MPSAFE */ int sys_extpwritev(struct extpwritev_args *uap) { struct thread *td = curthread; struct uio auio; struct iovec aiov[UIO_SMALLIOV], *iov = NULL; int error; int flags; error = iovec_copyin(uap->iovp, &iov, aiov, uap->iovcnt, &auio.uio_resid); if (error) return (error); auio.uio_iov = iov; auio.uio_iovcnt = uap->iovcnt; auio.uio_offset = uap->offset; auio.uio_rw = UIO_WRITE; auio.uio_segflg = UIO_USERSPACE; auio.uio_td = td; flags = uap->flags & O_FMASK; if (uap->offset != (off_t)-1) flags |= O_FOFFSET; error = kern_pwritev(uap->fd, &auio, flags, &uap->sysmsg_szresult); iovec_free(&iov, aiov); return(error); } /* * MPSAFE */ int kern_pwritev(int fd, struct uio *auio, int flags, size_t *res) { struct thread *td = curthread; struct file *fp; int error; fp = holdfp(td, fd, FWRITE); if (fp == NULL) return (EBADF); else if ((flags & O_FOFFSET) && fp->f_type != DTYPE_VNODE) { error = ESPIPE; } else { error = dofilewrite(fd, fp, auio, flags, res); } dropfp(td, fd, fp); return(error); } /* * Common code for writev and pwritev that writes data to * a file using the passed in uio, offset, and flags. * * MPALMOSTSAFE - ktrace needs help */ static int dofilewrite(int fd, struct file *fp, struct uio *auio, int flags, size_t *res) { struct thread *td = curthread; struct lwp *lp = td->td_lwp; int error; size_t len; #ifdef KTRACE struct iovec *ktriov = NULL; struct uio ktruio; #endif #ifdef KTRACE /* * if tracing, save a copy of iovec and uio */ if (KTRPOINT(td, KTR_GENIO)) { int iovlen = auio->uio_iovcnt * sizeof(struct iovec); ktriov = kmalloc(iovlen, M_TEMP, M_WAITOK); bcopy((caddr_t)auio->uio_iov, (caddr_t)ktriov, iovlen); ktruio = *auio; } #endif len = auio->uio_resid; error = fo_write(fp, auio, fp->f_cred, flags); if (error) { if (auio->uio_resid != len && (error == ERESTART || error == EINTR || error == EWOULDBLOCK)) error = 0; /* Socket layer is responsible for issuing SIGPIPE. */ if (error == EPIPE && fp->f_type != DTYPE_SOCKET) lwpsignal(lp->lwp_proc, lp, SIGPIPE); } #ifdef KTRACE if (ktriov != NULL) { if (error == 0) { ktruio.uio_iov = ktriov; ktruio.uio_resid = len - auio->uio_resid; ktrgenio(lp, fd, UIO_WRITE, &ktruio, error); } kfree(ktriov, M_TEMP); } #endif if (error == 0) *res = len - auio->uio_resid; return(error); } /* * Ioctl system call * * MPSAFE */ int sys_ioctl(struct ioctl_args *uap) { int error; error = mapped_ioctl(uap->fd, uap->com, uap->data, NULL, &uap->sysmsg); return (error); } struct ioctl_map_entry { const char *subsys; struct ioctl_map_range *cmd_ranges; LIST_ENTRY(ioctl_map_entry) entries; }; /* * The true heart of all ioctl syscall handlers (native, emulation). * If map != NULL, it will be searched for a matching entry for com, * and appropriate conversions/conversion functions will be utilized. * * MPSAFE */ int mapped_ioctl(int fd, u_long com, caddr_t uspc_data, struct ioctl_map *map, struct sysmsg *msg) { struct thread *td = curthread; struct proc *p = td->td_proc; struct ucred *cred; struct file *fp; struct ioctl_map_range *iomc = NULL; int error; u_int size; u_long ocom = com; caddr_t data, memp; int tmp; #define STK_PARAMS 128 union { char stkbuf[STK_PARAMS]; long align; } ubuf; KKASSERT(p); cred = td->td_ucred; memp = NULL; fp = holdfp(td, fd, FREAD|FWRITE); if (fp == NULL) return(EBADF); if (map != NULL) { /* obey translation map */ u_long maskcmd; struct ioctl_map_entry *e; maskcmd = com & map->mask; lwkt_gettoken(&mioctl_token); LIST_FOREACH(e, &map->mapping, entries) { for (iomc = e->cmd_ranges; iomc->start != 0 || iomc->maptocmd != 0 || iomc->wrapfunc != NULL || iomc->mapfunc != NULL; iomc++) { if (maskcmd >= iomc->start && maskcmd <= iomc->end) break; } /* Did we find a match? */ if (iomc->start != 0 || iomc->maptocmd != 0 || iomc->wrapfunc != NULL || iomc->mapfunc != NULL) break; } lwkt_reltoken(&mioctl_token); if (iomc == NULL || (iomc->start == 0 && iomc->maptocmd == 0 && iomc->wrapfunc == NULL && iomc->mapfunc == NULL)) { kprintf("%s: 'ioctl' fd=%d, cmd=0x%lx ('%c',%d) not implemented\n", map->sys, fd, maskcmd, (int)((maskcmd >> 8) & 0xff), (int)(maskcmd & 0xff)); error = EINVAL; goto done; } /* * If it's a non-range one to one mapping, maptocmd should be * correct. If it's a ranged one to one mapping, we pass the * original value of com, and for a range mapped to a different * range, we always need a mapping function to translate the * ioctl to our native ioctl. Ex. 6500-65ff <-> 9500-95ff */ if (iomc->start == iomc->end && iomc->maptocmd == iomc->maptoend) { com = iomc->maptocmd; } else if (iomc->start == iomc->maptocmd && iomc->end == iomc->maptoend) { if (iomc->mapfunc != NULL) com = iomc->mapfunc(iomc->start, iomc->end, iomc->start, iomc->end, com, com); } else { if (iomc->mapfunc != NULL) { com = iomc->mapfunc(iomc->start, iomc->end, iomc->maptocmd, iomc->maptoend, com, ocom); } else { kprintf("%s: Invalid mapping for fd=%d, cmd=%#lx ('%c',%d)\n", map->sys, fd, maskcmd, (int)((maskcmd >> 8) & 0xff), (int)(maskcmd & 0xff)); error = EINVAL; goto done; } } } switch (com) { case FIONCLEX: error = fclrfdflags(p->p_fd, fd, UF_EXCLOSE); goto done; case FIOCLEX: error = fsetfdflags(p->p_fd, fd, UF_EXCLOSE); goto done; } /* * Interpret high order word to find amount of data to be * copied to/from the user's address space. */ size = IOCPARM_LEN(com); if (size > IOCPARM_MAX) { error = ENOTTY; goto done; } if ((com & IOC_VOID) == 0 && size > sizeof(ubuf.stkbuf)) { memp = kmalloc(size, M_IOCTLOPS, M_WAITOK); data = memp; } else { memp = NULL; data = ubuf.stkbuf; } if (com & IOC_VOID) { *(caddr_t *)data = uspc_data; } else if (com & IOC_IN) { if (size != 0) { error = copyin(uspc_data, data, (size_t)size); if (error) goto done; } else { *(caddr_t *)data = uspc_data; } } else if ((com & IOC_OUT) != 0 && size) { /* * Zero the buffer so the user always * gets back something deterministic. */ bzero(data, (size_t)size); } switch (com) { case FIONBIO: if ((tmp = *(int *)data)) atomic_set_int(&fp->f_flag, FNONBLOCK); else atomic_clear_int(&fp->f_flag, FNONBLOCK); error = 0; break; case FIOASYNC: if ((tmp = *(int *)data)) atomic_set_int(&fp->f_flag, FASYNC); else atomic_clear_int(&fp->f_flag, FASYNC); error = fo_ioctl(fp, FIOASYNC, (caddr_t)&tmp, cred, msg); break; default: /* * If there is a override function, * call it instead of directly routing the call */ if (map != NULL && iomc->wrapfunc != NULL) error = iomc->wrapfunc(fp, com, ocom, data, cred); else error = fo_ioctl(fp, com, data, cred, msg); /* * Copy any data to user, size was * already set and checked above. */ if (error == 0 && (com & IOC_OUT) != 0 && size != 0) error = copyout(data, uspc_data, (size_t)size); break; } done: if (memp != NULL) kfree(memp, M_IOCTLOPS); dropfp(td, fd, fp); return(error); } /* * MPSAFE */ int mapped_ioctl_register_handler(struct ioctl_map_handler *he) { struct ioctl_map_entry *ne; KKASSERT(he != NULL && he->map != NULL && he->cmd_ranges != NULL && he->subsys != NULL && *he->subsys != '\0'); ne = kmalloc(sizeof(struct ioctl_map_entry), M_IOCTLMAP, M_WAITOK | M_ZERO); ne->subsys = he->subsys; ne->cmd_ranges = he->cmd_ranges; lwkt_gettoken(&mioctl_token); LIST_INSERT_HEAD(&he->map->mapping, ne, entries); lwkt_reltoken(&mioctl_token); return(0); } /* * MPSAFE */ int mapped_ioctl_unregister_handler(struct ioctl_map_handler *he) { struct ioctl_map_entry *ne; int error = EINVAL; KKASSERT(he != NULL && he->map != NULL && he->cmd_ranges != NULL); lwkt_gettoken(&mioctl_token); LIST_FOREACH(ne, &he->map->mapping, entries) { if (ne->cmd_ranges == he->cmd_ranges) { LIST_REMOVE(ne, entries); kfree(ne, M_IOCTLMAP); error = 0; break; } } lwkt_reltoken(&mioctl_token); return(error); } static int nselcoll; /* Select collisions since boot */ int selwait; SYSCTL_INT(_kern, OID_AUTO, nselcoll, CTLFLAG_RD, &nselcoll, 0, ""); static int nseldebug; SYSCTL_INT(_kern, OID_AUTO, nseldebug, CTLFLAG_RW, &nseldebug, 0, ""); /* * Select system call. * * MPSAFE */ int sys_select(struct select_args *uap) { struct timeval ktv; struct timespec *ktsp, kts; int error; /* * Get timeout if any. */ if (uap->tv != NULL) { error = copyin(uap->tv, &ktv, sizeof (ktv)); if (error) return (error); TIMEVAL_TO_TIMESPEC(&ktv, &kts); ktsp = &kts; } else { ktsp = NULL; } /* * Do real work. */ error = doselect(uap->nd, uap->in, uap->ou, uap->ex, ktsp, &uap->sysmsg_result); return (error); } /* * Pselect system call. */ int sys_pselect(struct pselect_args *uap) { struct thread *td = curthread; struct lwp *lp = td->td_lwp; struct timespec *ktsp, kts; sigset_t sigmask; int error; /* * Get timeout if any. */ if (uap->ts != NULL) { error = copyin(uap->ts, &kts, sizeof (kts)); if (error) return (error); ktsp = &kts; } else { ktsp = NULL; } /* * Install temporary signal mask if any provided. */ if (uap->sigmask != NULL) { error = copyin(uap->sigmask, &sigmask, sizeof(sigmask)); if (error) return (error); lwkt_gettoken(&lp->lwp_proc->p_token); lp->lwp_oldsigmask = lp->lwp_sigmask; SIG_CANTMASK(sigmask); lp->lwp_sigmask = sigmask; lwkt_reltoken(&lp->lwp_proc->p_token); } /* * Do real job. */ error = doselect(uap->nd, uap->in, uap->ou, uap->ex, ktsp, &uap->sysmsg_result); if (uap->sigmask != NULL) { lwkt_gettoken(&lp->lwp_proc->p_token); /* doselect() responsible for turning ERESTART into EINTR */ KKASSERT(error != ERESTART); if (error == EINTR) { /* * We can't restore the previous signal mask now * because it could block the signal that interrupted * us. So make a note to restore it after executing * the handler. */ lp->lwp_flags |= LWP_OLDMASK; } else { /* * No handler to run. Restore previous mask immediately. */ lp->lwp_sigmask = lp->lwp_oldsigmask; } lwkt_reltoken(&lp->lwp_proc->p_token); } return (error); } static int select_copyin(void *arg, struct kevent *kevp, int maxevents, int *events) { struct select_kevent_copyin_args *skap = NULL; struct kevent *kev; int fd; kfd_set *fdp = NULL; short filter = 0; u_int fflags = 0; skap = (struct select_kevent_copyin_args *)arg; if (*events == maxevents) return (0); while (skap->active_set < COPYIN_DONE) { switch (skap->active_set) { case COPYIN_READ: /* * Register descriptors for the read filter */ fdp = skap->read_set; filter = EVFILT_READ; fflags = NOTE_OLDAPI; if (fdp) break; ++skap->active_set; skap->proc_fds = 0; /* fall through */ case COPYIN_WRITE: /* * Register descriptors for the write filter */ fdp = skap->write_set; filter = EVFILT_WRITE; fflags = NOTE_OLDAPI; if (fdp) break; ++skap->active_set; skap->proc_fds = 0; /* fall through */ case COPYIN_EXCEPT: /* * Register descriptors for the exception filter */ fdp = skap->except_set; filter = EVFILT_EXCEPT; fflags = NOTE_OLDAPI | NOTE_OOB; if (fdp) break; ++skap->active_set; skap->proc_fds = 0; /* fall through */ case COPYIN_DONE: /* * Nothing left to register */ return(0); /* NOT REACHED */ } while (skap->proc_fds < skap->num_fds) { fd = skap->proc_fds; if (FD_ISSET(fd, fdp)) { kev = &kevp[*events]; EV_SET(kev, fd, filter, EV_ADD|EV_ENABLE, fflags, 0, (void *)(uintptr_t) skap->lwp->lwp_kqueue_serial); FD_CLR(fd, fdp); ++*events; if (nseldebug) { kprintf("select fd %d filter %d " "serial %ju\n", fd, filter, (uintmax_t) skap->lwp->lwp_kqueue_serial); } } ++skap->proc_fds; if (*events == maxevents) return (0); } skap->active_set++; skap->proc_fds = 0; } return (0); } static int select_copyout(void *arg, struct kevent *kevp, int count, int *res) { struct select_kevent_copyin_args *skap; struct kevent kev; int i; int n; skap = (struct select_kevent_copyin_args *)arg; for (i = 0; i < count; ++i) { /* * Filter out and delete spurious events */ if ((uint64_t)(uintptr_t)kevp[i].udata != skap->lwp->lwp_kqueue_serial) { kev = kevp[i]; kev.flags = EV_DISABLE|EV_DELETE; n = 1; kqueue_register(&skap->lwp->lwp_kqueue, &kev, &n); if (nseldebug) { kprintf("select fd %ju mismatched serial %ju\n", (uintmax_t)kevp[i].ident, (uintmax_t)skap->lwp->lwp_kqueue_serial); } continue; } /* * Handle errors */ if (kevp[i].flags & EV_ERROR) { int error = kevp[i].data; switch (error) { case EBADF: /* * A bad file descriptor is considered a * fatal error for select, bail out. */ skap->error = error; *res = -1; return error; default: /* * Select silently swallows any unknown errors * for descriptors in the read or write sets. * * ALWAYS filter out EOPNOTSUPP errors from * filters (at least until all filters support * EVFILT_EXCEPT) * * We also filter out ENODEV since dev_dkqfilter * returns ENODEV if EOPNOTSUPP is returned in an * inner call. * * XXX: fix this */ if (kevp[i].filter != EVFILT_READ && kevp[i].filter != EVFILT_WRITE && error != EOPNOTSUPP && error != ENODEV) { skap->error = error; *res = -1; return error; } break; } if (nseldebug) kprintf("select fd %ju filter %d error %d\n", (uintmax_t)kevp[i].ident, kevp[i].filter, error); continue; } switch (kevp[i].filter) { case EVFILT_READ: FD_SET(kevp[i].ident, skap->read_set); break; case EVFILT_WRITE: FD_SET(kevp[i].ident, skap->write_set); break; case EVFILT_EXCEPT: FD_SET(kevp[i].ident, skap->except_set); break; } ++*res; } return (0); } /* * Copy select bits in from userland. Allocate kernel memory if the * set is large. */ static int getbits(int bytes, fd_set *in_set, kfd_set **out_set, kfd_set *tmp_set) { int error; if (in_set) { if (bytes < sizeof(*tmp_set)) *out_set = tmp_set; else *out_set = kmalloc(bytes, M_SELECT, M_WAITOK); error = copyin(in_set, *out_set, bytes); } else { *out_set = NULL; error = 0; } return (error); } /* * Copy returned select bits back out to userland. */ static int putbits(int bytes, kfd_set *in_set, fd_set *out_set) { int error; if (in_set) { error = copyout(in_set, out_set, bytes); } else { error = 0; } return (error); } static int dotimeout_only(struct timespec *ts) { return(nanosleep1(ts, NULL)); } /* * Common code for sys_select() and sys_pselect(). * * in, out and ex are userland pointers. ts must point to validated * kernel-side timeout value or NULL for infinite timeout. res must * point to syscall return value. */ static int doselect(int nd, fd_set *read, fd_set *write, fd_set *except, struct timespec *ts, int *res) { struct proc *p = curproc; struct select_kevent_copyin_args *kap, ka; int bytes, error; kfd_set read_tmp; kfd_set write_tmp; kfd_set except_tmp; *res = 0; if (nd < 0) return (EINVAL); if (nd == 0 && ts) return (dotimeout_only(ts)); if (nd > p->p_fd->fd_nfiles) /* limit kmalloc */ nd = p->p_fd->fd_nfiles; kap = &ka; kap->lwp = curthread->td_lwp; kap->num_fds = nd; kap->proc_fds = 0; kap->error = 0; kap->active_set = COPYIN_READ; /* * Calculate bytes based on the number of __fd_mask[] array entries * multiplied by the size of __fd_mask. */ bytes = howmany(nd, __NFDBITS) * sizeof(__fd_mask); /* kap->read_set = NULL; not needed */ kap->write_set = NULL; kap->except_set = NULL; error = getbits(bytes, read, &kap->read_set, &read_tmp); if (error == 0) error = getbits(bytes, write, &kap->write_set, &write_tmp); if (error == 0) error = getbits(bytes, except, &kap->except_set, &except_tmp); if (error) goto done; /* * NOTE: Make sure the max events passed to kern_kevent() is * effectively unlimited. (nd * 3) accomplishes this. * * (*res) continues to increment as returned events are * loaded in. */ error = kern_kevent(&kap->lwp->lwp_kqueue, 0x7FFFFFFF, res, kap, select_copyin, select_copyout, ts, 0); if (error == 0) error = putbits(bytes, kap->read_set, read); if (error == 0) error = putbits(bytes, kap->write_set, write); if (error == 0) error = putbits(bytes, kap->except_set, except); /* * An error from an individual event that should be passed * back to userland (EBADF) */ if (kap->error) error = kap->error; /* * Clean up. */ done: if (kap->read_set && kap->read_set != &read_tmp) kfree(kap->read_set, M_SELECT); if (kap->write_set && kap->write_set != &write_tmp) kfree(kap->write_set, M_SELECT); if (kap->except_set && kap->except_set != &except_tmp) kfree(kap->except_set, M_SELECT); kap->lwp->lwp_kqueue_serial += kap->num_fds; return (error); } /* * Poll system call. * * MPSAFE */ int sys_poll(struct poll_args *uap) { struct timespec ts, *tsp; int error; if (uap->timeout != INFTIM) { if (uap->timeout < 0) return (EINVAL); ts.tv_sec = uap->timeout / 1000; ts.tv_nsec = (uap->timeout % 1000) * 1000 * 1000; tsp = &ts; } else { tsp = NULL; } error = dopoll(uap->nfds, uap->fds, tsp, &uap->sysmsg_result, 0); return (error); } /* * Ppoll system call. * * MPSAFE */ int sys_ppoll(struct ppoll_args *uap) { struct thread *td = curthread; struct lwp *lp = td->td_lwp; struct timespec *ktsp, kts; sigset_t sigmask; int error; /* * Get timeout if any. */ if (uap->ts != NULL) { error = copyin(uap->ts, &kts, sizeof (kts)); if (error) return (error); ktsp = &kts; } else { ktsp = NULL; } /* * Install temporary signal mask if any provided. */ if (uap->sigmask != NULL) { error = copyin(uap->sigmask, &sigmask, sizeof(sigmask)); if (error) return (error); lwkt_gettoken(&lp->lwp_proc->p_token); lp->lwp_oldsigmask = lp->lwp_sigmask; SIG_CANTMASK(sigmask); lp->lwp_sigmask = sigmask; lwkt_reltoken(&lp->lwp_proc->p_token); } error = dopoll(uap->nfds, uap->fds, ktsp, &uap->sysmsg_result, ktsp != NULL ? KEVENT_TIMEOUT_PRECISE : 0); if (uap->sigmask != NULL) { lwkt_gettoken(&lp->lwp_proc->p_token); /* dopoll() responsible for turning ERESTART into EINTR */ KKASSERT(error != ERESTART); if (error == EINTR) { /* * We can't restore the previous signal mask now * because it could block the signal that interrupted * us. So make a note to restore it after executing * the handler. */ lp->lwp_flags |= LWP_OLDMASK; } else { /* * No handler to run. Restore previous mask immediately. */ lp->lwp_sigmask = lp->lwp_oldsigmask; } lwkt_reltoken(&lp->lwp_proc->p_token); } return (error); } static int poll_copyin(void *arg, struct kevent *kevp, int maxevents, int *events) { struct poll_kevent_copyin_args *pkap; struct pollfd *pfd; struct kevent *kev; int kev_count; pkap = (struct poll_kevent_copyin_args *)arg; while (pkap->pfds < pkap->nfds) { pfd = &pkap->fds[pkap->pfds]; /* Clear return events */ pfd->revents = 0; /* Do not check if fd is equal to -1 */ if (pfd->fd == -1) { ++pkap->pfds; continue; } kev_count = 0; if (pfd->events & (POLLIN | POLLRDNORM)) kev_count++; if (pfd->events & (POLLOUT | POLLWRNORM)) kev_count++; if (pfd->events & (POLLPRI | POLLRDBAND)) kev_count++; if (*events + kev_count > maxevents) return (0); /* * NOTE: A combined serial number and poll array index is * stored in kev->udata. */ kev = &kevp[*events]; if (pfd->events & (POLLIN | POLLRDNORM)) { EV_SET(kev++, pfd->fd, EVFILT_READ, EV_ADD|EV_ENABLE, NOTE_OLDAPI, 0, (void *)(uintptr_t) (pkap->lwp->lwp_kqueue_serial + pkap->pfds)); } if (pfd->events & (POLLOUT | POLLWRNORM)) { EV_SET(kev++, pfd->fd, EVFILT_WRITE, EV_ADD|EV_ENABLE, NOTE_OLDAPI, 0, (void *)(uintptr_t) (pkap->lwp->lwp_kqueue_serial + pkap->pfds)); } if (pfd->events & (POLLPRI | POLLRDBAND)) { EV_SET(kev++, pfd->fd, EVFILT_EXCEPT, EV_ADD|EV_ENABLE, NOTE_OLDAPI | NOTE_OOB, 0, (void *)(uintptr_t) (pkap->lwp->lwp_kqueue_serial + pkap->pfds)); } if (nseldebug) { kprintf("poll index %d/%d fd %d events %08x " "serial %ju\n", pkap->pfds, pkap->nfds-1, pfd->fd, pfd->events, (uintmax_t)pkap->lwp->lwp_kqueue_serial); } ++pkap->pfds; (*events) += kev_count; } return (0); } static int poll_copyout(void *arg, struct kevent *kevp, int count, int *res) { struct poll_kevent_copyin_args *pkap; struct pollfd *pfd; struct kevent kev; int count_res; int i; int n; uint64_t pi; pkap = (struct poll_kevent_copyin_args *)arg; for (i = 0; i < count; ++i) { /* * Extract the poll array index and delete spurious events. * We can easily tell if the serial number is incorrect * by checking whether the extracted index is out of range. */ pi = (uint64_t)(uintptr_t)kevp[i].udata - pkap->lwp->lwp_kqueue_serial; if (pi >= pkap->nfds) { kev = kevp[i]; kev.flags = EV_DISABLE|EV_DELETE; n = 1; kqueue_register(&pkap->lwp->lwp_kqueue, &kev, &n); if (nseldebug) { kprintf("poll index %ju out of range against " "serial %ju\n", (uintmax_t)pi, (uintmax_t)pkap->lwp->lwp_kqueue_serial); } continue; } pfd = &pkap->fds[pi]; if (kevp[i].ident == pfd->fd) { /* * A single descriptor may generate an error against * more than one filter, make sure to set the * appropriate flags but do not increment (*res) * more than once. */ count_res = (pfd->revents == 0); if (kevp[i].flags & EV_ERROR) { switch(kevp[i].data) { case EBADF: case POLLNVAL: /* Bad file descriptor */ if (count_res) ++*res; pfd->revents |= POLLNVAL; break; default: /* * Poll silently swallows any unknown * errors except in the case of POLLPRI * (OOB/urgent data). * * ALWAYS filter out EOPNOTSUPP errors * from filters, common applications * set POLLPRI|POLLRDBAND and most * filters do not support EVFILT_EXCEPT. * * We also filter out ENODEV since dev_dkqfilter * returns ENODEV if EOPNOTSUPP is returned in an * inner call. * * XXX: fix this */ if (kevp[i].filter != EVFILT_READ && kevp[i].filter != EVFILT_WRITE && kevp[i].data != EOPNOTSUPP && kevp[i].data != ENODEV) { if (count_res) ++*res; pfd->revents |= POLLERR; } break; } if (nseldebug) { kprintf("poll index %ju fd %d " "filter %d error %jd\n", (uintmax_t)pi, pfd->fd, kevp[i].filter, (intmax_t)kevp[i].data); } continue; } switch (kevp[i].filter) { case EVFILT_READ: #if 0 /* * NODATA on the read side can indicate a * half-closed situation and not necessarily * a disconnect, so depend on the user * issuing a read() and getting 0 bytes back. */ if (kevp[i].flags & EV_NODATA) pfd->revents |= POLLHUP; #endif if ((kevp[i].flags & EV_EOF) && kevp[i].fflags != 0) pfd->revents |= POLLERR; if (pfd->events & POLLIN) pfd->revents |= POLLIN; if (pfd->events & POLLRDNORM) pfd->revents |= POLLRDNORM; break; case EVFILT_WRITE: /* * As per the OpenGroup POLLHUP is mutually * exclusive with the writability flags. I * consider this a bit broken but... * * In this case a disconnect is implied even * for a half-closed (write side) situation. */ if (kevp[i].flags & EV_EOF) { pfd->revents |= POLLHUP; if (kevp[i].fflags != 0) pfd->revents |= POLLERR; } else { if (pfd->events & POLLOUT) pfd->revents |= POLLOUT; if (pfd->events & POLLWRNORM) pfd->revents |= POLLWRNORM; } break; case EVFILT_EXCEPT: /* * EV_NODATA should never be tagged for this * filter. */ if (pfd->events & POLLPRI) pfd->revents |= POLLPRI; if (pfd->events & POLLRDBAND) pfd->revents |= POLLRDBAND; break; } if (nseldebug) { kprintf("poll index %ju/%d fd %d " "revents %08x\n", (uintmax_t)pi, pkap->nfds, pfd->fd, pfd->revents); } if (count_res && pfd->revents) ++*res; } else { if (nseldebug) { kprintf("poll index %ju mismatch %ju/%d\n", (uintmax_t)pi, (uintmax_t)kevp[i].ident, pfd->fd); } } } return (0); } static int dopoll(int nfds, struct pollfd *fds, struct timespec *ts, int *res, int flags) { struct poll_kevent_copyin_args ka; struct pollfd sfds[64]; int bytes; int error; *res = 0; if (nfds < 0) return (EINVAL); if (nfds == 0 && ts) return (dotimeout_only(ts)); /* * This is a bit arbitrary but we need to limit internal kmallocs. */ if (nfds > maxfilesperproc * 2) nfds = maxfilesperproc * 2; bytes = sizeof(struct pollfd) * nfds; ka.lwp = curthread->td_lwp; ka.nfds = nfds; ka.pfds = 0; ka.error = 0; if (ka.nfds < 64) ka.fds = sfds; else ka.fds = kmalloc(bytes, M_SELECT, M_WAITOK); error = copyin(fds, ka.fds, bytes); if (error == 0) error = kern_kevent(&ka.lwp->lwp_kqueue, 0x7FFFFFFF, res, &ka, poll_copyin, poll_copyout, ts, flags); if (error == 0) error = copyout(ka.fds, fds, bytes); if (ka.fds != sfds) kfree(ka.fds, M_SELECT); ka.lwp->lwp_kqueue_serial += nfds; return (error); } static int socket_wait_copyin(void *arg, struct kevent *kevp, int maxevents, int *events) { return (0); } static int socket_wait_copyout(void *arg, struct kevent *kevp, int count, int *res) { ++*res; return (0); } extern struct fileops socketops; /* * NOTE: Callers of socket_wait() must already have a reference on the * socket. */ int socket_wait(struct socket *so, struct timespec *ts, int *res) { struct thread *td = curthread; struct file *fp; struct kqueue kq; struct kevent kev; int error, fd; int n; if ((error = falloc(td->td_lwp, &fp, &fd)) != 0) return (error); fp->f_type = DTYPE_SOCKET; fp->f_flag = FREAD | FWRITE; fp->f_ops = &socketops; fp->f_data = so; fsetfd(td->td_lwp->lwp_proc->p_fd, fp, fd); fsetfdflags(td->td_proc->p_fd, fd, UF_EXCLOSE); bzero(&kq, sizeof(kq)); kqueue_init(&kq, td->td_lwp->lwp_proc->p_fd); EV_SET(&kev, fd, EVFILT_READ, EV_ADD|EV_ENABLE, 0, 0, NULL); n = 1; if ((error = kqueue_register(&kq, &kev, &n)) != 0) { fdrop(fp); return (error); } error = kern_kevent(&kq, 1, res, NULL, socket_wait_copyin, socket_wait_copyout, ts, 0); EV_SET(&kev, fd, EVFILT_READ, EV_DELETE|EV_DISABLE, 0, 0, NULL); n = 1; kqueue_register(&kq, &kev, &n); fp->f_ops = &badfileops; fdrop(fp); return (error); } /* * OpenBSD poll system call. * XXX this isn't quite a true representation.. OpenBSD uses select ops. * * MPSAFE */ int sys_openbsd_poll(struct openbsd_poll_args *uap) { return (sys_poll((struct poll_args *)uap)); } /*ARGSUSED*/ int seltrue(cdev_t dev, int events) { return (events & (POLLIN | POLLOUT | POLLRDNORM | POLLWRNORM)); }