/* $NetBSD: sys_aio.c,v 1.44.4.1 2024/11/20 14:01:59 martin Exp $ */ /* * Copyright (c) 2007 Mindaugas Rasiukevicius * 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 AUTHOR 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 AUTHOR 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. */ /* * Implementation of POSIX asynchronous I/O. * Defined in the Base Definitions volume of IEEE Std 1003.1-2001. */ #include __KERNEL_RCSID(0, "$NetBSD: sys_aio.c,v 1.44.4.1 2024/11/20 14:01:59 martin Exp $"); #ifdef _KERNEL_OPT #include "opt_ddb.h" #endif #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include MODULE(MODULE_CLASS_MISC, aio, NULL); /* * System-wide limits and counter of AIO operations. */ u_int aio_listio_max = AIO_LISTIO_MAX; static u_int aio_max = AIO_MAX; static u_int aio_jobs_count; static struct sysctllog *aio_sysctl; static struct pool aio_job_pool; static struct pool aio_lio_pool; static void * aio_ehook; static void aio_worker(void *); static void aio_process(struct aio_job *); static void aio_sendsig(struct proc *, struct sigevent *); static int aio_enqueue_job(int, void *, struct lio_req *); static void aio_exit(proc_t *, void *); static int sysctl_aio_listio_max(SYSCTLFN_PROTO); static int sysctl_aio_max(SYSCTLFN_PROTO); static int sysctl_aio_init(void); static const struct syscall_package aio_syscalls[] = { { SYS_aio_cancel, 0, (sy_call_t *)sys_aio_cancel }, { SYS_aio_error, 0, (sy_call_t *)sys_aio_error }, { SYS_aio_fsync, 0, (sy_call_t *)sys_aio_fsync }, { SYS_aio_read, 0, (sy_call_t *)sys_aio_read }, { SYS_aio_return, 0, (sy_call_t *)sys_aio_return }, { SYS___aio_suspend50, 0, (sy_call_t *)sys___aio_suspend50 }, { SYS_aio_write, 0, (sy_call_t *)sys_aio_write }, { SYS_lio_listio, 0, (sy_call_t *)sys_lio_listio }, { 0, 0, NULL }, }; /* * Tear down all AIO state. */ static int aio_fini(bool interface) { int error; proc_t *p; if (interface) { /* Stop syscall activity. */ error = syscall_disestablish(NULL, aio_syscalls); if (error != 0) return error; /* Abort if any processes are using AIO. */ mutex_enter(proc_lock); PROCLIST_FOREACH(p, &allproc) { if (p->p_aio != NULL) break; } mutex_exit(proc_lock); if (p != NULL) { error = syscall_establish(NULL, aio_syscalls); KASSERT(error == 0); return EBUSY; } } if (aio_sysctl != NULL) sysctl_teardown(&aio_sysctl); KASSERT(aio_jobs_count == 0); exithook_disestablish(aio_ehook); pool_destroy(&aio_job_pool); pool_destroy(&aio_lio_pool); return 0; } /* * Initialize global AIO state. */ static int aio_init(void) { int error; pool_init(&aio_job_pool, sizeof(struct aio_job), 0, 0, 0, "aio_jobs_pool", &pool_allocator_nointr, IPL_NONE); pool_init(&aio_lio_pool, sizeof(struct lio_req), 0, 0, 0, "aio_lio_pool", &pool_allocator_nointr, IPL_NONE); aio_ehook = exithook_establish(aio_exit, NULL); error = sysctl_aio_init(); if (error != 0) { (void)aio_fini(false); return error; } error = syscall_establish(NULL, aio_syscalls); if (error != 0) (void)aio_fini(false); return error; } /* * Module interface. */ static int aio_modcmd(modcmd_t cmd, void *arg) { switch (cmd) { case MODULE_CMD_INIT: return aio_init(); case MODULE_CMD_FINI: return aio_fini(true); default: return ENOTTY; } } /* * Initialize Asynchronous I/O data structures for the process. */ static int aio_procinit(struct proc *p) { struct aioproc *aio; struct lwp *l; int error; vaddr_t uaddr; /* Allocate and initialize AIO structure */ aio = kmem_zalloc(sizeof(struct aioproc), KM_SLEEP); /* Initialize queue and their synchronization structures */ mutex_init(&aio->aio_mtx, MUTEX_DEFAULT, IPL_NONE); cv_init(&aio->aio_worker_cv, "aiowork"); cv_init(&aio->done_cv, "aiodone"); TAILQ_INIT(&aio->jobs_queue); /* * Create an AIO worker thread. * XXX: Currently, AIO thread is not protected against user's actions. */ uaddr = uvm_uarea_alloc(); if (uaddr == 0) { aio_exit(p, aio); return EAGAIN; } error = lwp_create(curlwp, p, uaddr, 0, NULL, 0, aio_worker, NULL, &l, curlwp->l_class, &curlwp->l_sigmask, &curlwp->l_sigstk); if (error != 0) { uvm_uarea_free(uaddr); aio_exit(p, aio); return error; } /* Recheck if we are really first */ mutex_enter(p->p_lock); if (p->p_aio) { mutex_exit(p->p_lock); aio_exit(p, aio); lwp_exit(l); return 0; } p->p_aio = aio; /* Complete the initialization of thread, and run it */ aio->aio_worker = l; lwp_lock(l); l->l_stat = LSRUN; l->l_priority = MAXPRI_USER; sched_enqueue(l, false); lwp_unlock(l); mutex_exit(p->p_lock); return 0; } /* * Exit of Asynchronous I/O subsystem of process. */ static void aio_exit(struct proc *p, void *cookie) { struct aio_job *a_job; struct aioproc *aio; if (cookie != NULL) aio = cookie; else if ((aio = p->p_aio) == NULL) return; /* Free AIO queue */ while (!TAILQ_EMPTY(&aio->jobs_queue)) { a_job = TAILQ_FIRST(&aio->jobs_queue); TAILQ_REMOVE(&aio->jobs_queue, a_job, list); pool_put(&aio_job_pool, a_job); atomic_dec_uint(&aio_jobs_count); } /* Destroy and free the entire AIO data structure */ cv_destroy(&aio->aio_worker_cv); cv_destroy(&aio->done_cv); mutex_destroy(&aio->aio_mtx); kmem_free(aio, sizeof(struct aioproc)); } /* * AIO worker thread and processor. */ static void aio_worker(void *arg) { struct proc *p = curlwp->l_proc; struct aioproc *aio = p->p_aio; struct aio_job *a_job; struct lio_req *lio; sigset_t oss, nss; int error __diagused, refcnt; /* * Make an empty signal mask, so it * handles only SIGKILL and SIGSTOP. */ sigfillset(&nss); mutex_enter(p->p_lock); error = sigprocmask1(curlwp, SIG_SETMASK, &nss, &oss); mutex_exit(p->p_lock); KASSERT(error == 0); for (;;) { /* * Loop for each job in the queue. If there * are no jobs then sleep. */ mutex_enter(&aio->aio_mtx); while ((a_job = TAILQ_FIRST(&aio->jobs_queue)) == NULL) { if (cv_wait_sig(&aio->aio_worker_cv, &aio->aio_mtx)) { /* * Thread was interrupted - check for * pending exit or suspend. */ mutex_exit(&aio->aio_mtx); lwp_userret(curlwp); mutex_enter(&aio->aio_mtx); } } /* Take the job from the queue */ aio->curjob = a_job; TAILQ_REMOVE(&aio->jobs_queue, a_job, list); atomic_dec_uint(&aio_jobs_count); aio->jobs_count--; mutex_exit(&aio->aio_mtx); /* Process an AIO operation */ aio_process(a_job); /* Copy data structure back to the user-space */ (void)copyout(&a_job->aiocbp, a_job->aiocb_uptr, sizeof(struct aiocb)); mutex_enter(&aio->aio_mtx); KASSERT(aio->curjob == a_job); aio->curjob = NULL; /* Decrease a reference counter, if there is a LIO structure */ lio = a_job->lio; refcnt = (lio != NULL ? --lio->refcnt : -1); /* Notify all suspenders */ cv_broadcast(&aio->done_cv); mutex_exit(&aio->aio_mtx); /* Send a signal, if any */ aio_sendsig(p, &a_job->aiocbp.aio_sigevent); /* Destroy the LIO structure */ if (refcnt == 0) { aio_sendsig(p, &lio->sig); pool_put(&aio_lio_pool, lio); } /* Destroy the job */ pool_put(&aio_job_pool, a_job); } /* NOTREACHED */ } static void aio_process(struct aio_job *a_job) { struct proc *p = curlwp->l_proc; struct aiocb *aiocbp = &a_job->aiocbp; struct file *fp; int fd = aiocbp->aio_fildes; int error = 0; KASSERT(a_job->aio_op != 0); if ((a_job->aio_op & (AIO_READ | AIO_WRITE)) != 0) { struct iovec aiov; struct uio auio; if (aiocbp->aio_nbytes > SSIZE_MAX) { error = EINVAL; goto done; } fp = fd_getfile(fd); if (fp == NULL) { error = EBADF; goto done; } aiov.iov_base = (void *)(uintptr_t)aiocbp->aio_buf; aiov.iov_len = aiocbp->aio_nbytes; auio.uio_iov = &aiov; auio.uio_iovcnt = 1; auio.uio_resid = aiocbp->aio_nbytes; auio.uio_vmspace = p->p_vmspace; if (a_job->aio_op & AIO_READ) { /* * Perform a Read operation */ KASSERT((a_job->aio_op & AIO_WRITE) == 0); if ((fp->f_flag & FREAD) == 0) { fd_putfile(fd); error = EBADF; goto done; } auio.uio_rw = UIO_READ; error = (*fp->f_ops->fo_read)(fp, &aiocbp->aio_offset, &auio, fp->f_cred, FOF_UPDATE_OFFSET); } else { /* * Perform a Write operation */ KASSERT(a_job->aio_op & AIO_WRITE); if ((fp->f_flag & FWRITE) == 0) { fd_putfile(fd); error = EBADF; goto done; } auio.uio_rw = UIO_WRITE; error = (*fp->f_ops->fo_write)(fp, &aiocbp->aio_offset, &auio, fp->f_cred, FOF_UPDATE_OFFSET); } fd_putfile(fd); /* Store the result value */ a_job->aiocbp.aio_nbytes -= auio.uio_resid; a_job->aiocbp._retval = (error == 0) ? a_job->aiocbp.aio_nbytes : -1; } else if ((a_job->aio_op & (AIO_SYNC | AIO_DSYNC)) != 0) { /* * Perform a file Sync operation */ struct vnode *vp; if ((error = fd_getvnode(fd, &fp)) != 0) goto done; if ((fp->f_flag & FWRITE) == 0) { fd_putfile(fd); error = EBADF; goto done; } vp = fp->f_vnode; vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); if (a_job->aio_op & AIO_DSYNC) { error = VOP_FSYNC(vp, fp->f_cred, FSYNC_WAIT | FSYNC_DATAONLY, 0, 0); } else if (a_job->aio_op & AIO_SYNC) { error = VOP_FSYNC(vp, fp->f_cred, FSYNC_WAIT, 0, 0); } VOP_UNLOCK(vp); fd_putfile(fd); /* Store the result value */ a_job->aiocbp._retval = (error == 0) ? 0 : -1; } else panic("aio_process: invalid operation code\n"); done: /* Job is done, set the error, if any */ a_job->aiocbp._errno = error; a_job->aiocbp._state = JOB_DONE; } /* * Send AIO signal. */ static void aio_sendsig(struct proc *p, struct sigevent *sig) { ksiginfo_t ksi; if (sig->sigev_signo == 0 || sig->sigev_notify == SIGEV_NONE) return; KSI_INIT(&ksi); ksi.ksi_signo = sig->sigev_signo; ksi.ksi_code = SI_ASYNCIO; ksi.ksi_value = sig->sigev_value; mutex_enter(proc_lock); kpsignal(p, &ksi, NULL); mutex_exit(proc_lock); } /* * Enqueue the job. */ static int aio_enqueue_job(int op, void *aiocb_uptr, struct lio_req *lio) { struct proc *p = curlwp->l_proc; struct aioproc *aio; struct aio_job *a_job; struct aiocb aiocbp; struct sigevent *sig; int error; /* Non-accurate check for the limit */ if (aio_jobs_count + 1 > aio_max) return EAGAIN; /* Get the data structure from user-space */ error = copyin(aiocb_uptr, &aiocbp, sizeof(struct aiocb)); if (error) return error; /* Check if signal is set, and validate it */ sig = &aiocbp.aio_sigevent; if (sig->sigev_signo < 0 || sig->sigev_signo >= NSIG || sig->sigev_notify < SIGEV_NONE || sig->sigev_notify > SIGEV_SA) return EINVAL; /* Buffer and byte count */ if (((AIO_SYNC | AIO_DSYNC) & op) == 0) if (aiocbp.aio_buf == NULL || aiocbp.aio_nbytes > SSIZE_MAX) return EINVAL; /* Check the opcode, if LIO_NOP - simply ignore */ if (op == AIO_LIO) { KASSERT(lio != NULL); if (aiocbp.aio_lio_opcode == LIO_WRITE) op = AIO_WRITE; else if (aiocbp.aio_lio_opcode == LIO_READ) op = AIO_READ; else return (aiocbp.aio_lio_opcode == LIO_NOP) ? 0 : EINVAL; } else { KASSERT(lio == NULL); } /* * Look for already existing job. If found - the job is in-progress. * According to POSIX this is invalid, so return the error. */ aio = p->p_aio; if (aio) { mutex_enter(&aio->aio_mtx); TAILQ_FOREACH(a_job, &aio->jobs_queue, list) { if (a_job->aiocb_uptr != aiocb_uptr) continue; mutex_exit(&aio->aio_mtx); return EINVAL; } mutex_exit(&aio->aio_mtx); } /* * Check if AIO structure is initialized, if not - initialize it. * In LIO case, we did that already. We will recheck this with * the lock in aio_procinit(). */ if (lio == NULL && p->p_aio == NULL) if (aio_procinit(p)) return EAGAIN; aio = p->p_aio; /* * Set the state with errno, and copy data * structure back to the user-space. */ aiocbp._state = JOB_WIP; aiocbp._errno = EINPROGRESS; aiocbp._retval = -1; error = copyout(&aiocbp, aiocb_uptr, sizeof(struct aiocb)); if (error) return error; /* Allocate and initialize a new AIO job */ a_job = pool_get(&aio_job_pool, PR_WAITOK | PR_ZERO); /* * Set the data. * Store the user-space pointer for searching. Since we * are storing only per proc pointers - it is safe. */ memcpy(&a_job->aiocbp, &aiocbp, sizeof(struct aiocb)); a_job->aiocb_uptr = aiocb_uptr; a_job->aio_op |= op; a_job->lio = lio; /* * Add the job to the queue, update the counters, and * notify the AIO worker thread to handle the job. */ mutex_enter(&aio->aio_mtx); /* Fail, if the limit was reached */ if (atomic_inc_uint_nv(&aio_jobs_count) > aio_max || aio->jobs_count >= aio_listio_max) { atomic_dec_uint(&aio_jobs_count); mutex_exit(&aio->aio_mtx); pool_put(&aio_job_pool, a_job); return EAGAIN; } TAILQ_INSERT_TAIL(&aio->jobs_queue, a_job, list); aio->jobs_count++; if (lio) lio->refcnt++; cv_signal(&aio->aio_worker_cv); mutex_exit(&aio->aio_mtx); /* * One would handle the errors only with aio_error() function. * This way is appropriate according to POSIX. */ return 0; } /* * Syscall functions. */ int sys_aio_cancel(struct lwp *l, const struct sys_aio_cancel_args *uap, register_t *retval) { /* { syscallarg(int) fildes; syscallarg(struct aiocb *) aiocbp; } */ struct proc *p = l->l_proc; struct aioproc *aio; struct aio_job *a_job; struct aiocb *aiocbp_ptr; struct lio_req *lio; struct filedesc *fdp = p->p_fd; unsigned int cn, errcnt, fildes; fdtab_t *dt; TAILQ_HEAD(, aio_job) tmp_jobs_list; /* Check for invalid file descriptor */ fildes = (unsigned int)SCARG(uap, fildes); dt = atomic_load_consume(&fdp->fd_dt); if (fildes >= dt->dt_nfiles) return EBADF; if (dt->dt_ff[fildes] == NULL || dt->dt_ff[fildes]->ff_file == NULL) return EBADF; /* Check if AIO structure is initialized */ if (p->p_aio == NULL) { *retval = AIO_NOTCANCELED; return 0; } aio = p->p_aio; aiocbp_ptr = (struct aiocb *)SCARG(uap, aiocbp); mutex_enter(&aio->aio_mtx); /* Cancel the jobs, and remove them from the queue */ cn = 0; TAILQ_INIT(&tmp_jobs_list); TAILQ_FOREACH(a_job, &aio->jobs_queue, list) { if (aiocbp_ptr) { if (aiocbp_ptr != a_job->aiocb_uptr) continue; if (fildes != a_job->aiocbp.aio_fildes) { mutex_exit(&aio->aio_mtx); return EBADF; } } else if (a_job->aiocbp.aio_fildes != fildes) continue; TAILQ_REMOVE(&aio->jobs_queue, a_job, list); TAILQ_INSERT_TAIL(&tmp_jobs_list, a_job, list); /* Decrease the counters */ atomic_dec_uint(&aio_jobs_count); aio->jobs_count--; lio = a_job->lio; if (lio != NULL && --lio->refcnt != 0) a_job->lio = NULL; cn++; if (aiocbp_ptr) break; } /* There are canceled jobs */ if (cn) *retval = AIO_CANCELED; /* We cannot cancel current job */ a_job = aio->curjob; if (a_job && ((a_job->aiocbp.aio_fildes == fildes) || (a_job->aiocb_uptr == aiocbp_ptr))) *retval = AIO_NOTCANCELED; mutex_exit(&aio->aio_mtx); /* Free the jobs after the lock */ errcnt = 0; while (!TAILQ_EMPTY(&tmp_jobs_list)) { a_job = TAILQ_FIRST(&tmp_jobs_list); TAILQ_REMOVE(&tmp_jobs_list, a_job, list); /* Set the errno and copy structures back to the user-space */ a_job->aiocbp._errno = ECANCELED; a_job->aiocbp._state = JOB_DONE; if (copyout(&a_job->aiocbp, a_job->aiocb_uptr, sizeof(struct aiocb))) errcnt++; /* Send a signal if any */ aio_sendsig(p, &a_job->aiocbp.aio_sigevent); if (a_job->lio) { lio = a_job->lio; aio_sendsig(p, &lio->sig); pool_put(&aio_lio_pool, lio); } pool_put(&aio_job_pool, a_job); } if (errcnt) return EFAULT; /* Set a correct return value */ if (*retval == 0) *retval = AIO_ALLDONE; return 0; } int sys_aio_error(struct lwp *l, const struct sys_aio_error_args *uap, register_t *retval) { /* { syscallarg(const struct aiocb *) aiocbp; } */ struct proc *p = l->l_proc; struct aioproc *aio = p->p_aio; struct aiocb aiocbp; int error; if (aio == NULL) return EINVAL; error = copyin(SCARG(uap, aiocbp), &aiocbp, sizeof(struct aiocb)); if (error) return error; if (aiocbp._state == JOB_NONE) return EINVAL; *retval = aiocbp._errno; return 0; } int sys_aio_fsync(struct lwp *l, const struct sys_aio_fsync_args *uap, register_t *retval) { /* { syscallarg(int) op; syscallarg(struct aiocb *) aiocbp; } */ int op = SCARG(uap, op); if ((op != O_DSYNC) && (op != O_SYNC)) return EINVAL; op = O_DSYNC ? AIO_DSYNC : AIO_SYNC; return aio_enqueue_job(op, SCARG(uap, aiocbp), NULL); } int sys_aio_read(struct lwp *l, const struct sys_aio_read_args *uap, register_t *retval) { /* { syscallarg(struct aiocb *) aiocbp; } */ return aio_enqueue_job(AIO_READ, SCARG(uap, aiocbp), NULL); } int sys_aio_return(struct lwp *l, const struct sys_aio_return_args *uap, register_t *retval) { /* { syscallarg(struct aiocb *) aiocbp; } */ struct proc *p = l->l_proc; struct aioproc *aio = p->p_aio; struct aiocb aiocbp; int error; if (aio == NULL) return EINVAL; error = copyin(SCARG(uap, aiocbp), &aiocbp, sizeof(struct aiocb)); if (error) return error; if (aiocbp._errno == EINPROGRESS || aiocbp._state != JOB_DONE) return EINVAL; *retval = aiocbp._retval; /* Reset the internal variables */ aiocbp._errno = 0; aiocbp._retval = -1; aiocbp._state = JOB_NONE; error = copyout(&aiocbp, SCARG(uap, aiocbp), sizeof(struct aiocb)); return error; } int sys___aio_suspend50(struct lwp *l, const struct sys___aio_suspend50_args *uap, register_t *retval) { /* { syscallarg(const struct aiocb *const[]) list; syscallarg(int) nent; syscallarg(const struct timespec *) timeout; } */ struct aiocb **list; struct timespec ts; int error, nent; nent = SCARG(uap, nent); if (nent <= 0 || nent > aio_listio_max) return EAGAIN; if (SCARG(uap, timeout)) { /* Convert timespec to ticks */ error = copyin(SCARG(uap, timeout), &ts, sizeof(struct timespec)); if (error) return error; } list = kmem_alloc(nent * sizeof(*list), KM_SLEEP); error = copyin(SCARG(uap, list), list, nent * sizeof(*list)); if (error) goto out; error = aio_suspend1(l, list, nent, SCARG(uap, timeout) ? &ts : NULL); out: kmem_free(list, nent * sizeof(*list)); return error; } int aio_suspend1(struct lwp *l, struct aiocb **aiocbp_list, int nent, struct timespec *ts) { struct proc *p = l->l_proc; struct aioproc *aio; struct aio_job *a_job; int i, error, timo; if (p->p_aio == NULL) return EAGAIN; aio = p->p_aio; if (ts) { timo = mstohz((ts->tv_sec * 1000) + (ts->tv_nsec / 1000000)); if (timo == 0 && ts->tv_sec == 0 && ts->tv_nsec > 0) timo = 1; if (timo <= 0) return EAGAIN; } else timo = 0; mutex_enter(&aio->aio_mtx); for (;;) { for (i = 0; i < nent; i++) { /* Skip NULL entries */ if (aiocbp_list[i] == NULL) continue; /* Skip current job */ if (aio->curjob) { a_job = aio->curjob; if (a_job->aiocb_uptr == aiocbp_list[i]) continue; } /* Look for a job in the queue */ TAILQ_FOREACH(a_job, &aio->jobs_queue, list) if (a_job->aiocb_uptr == aiocbp_list[i]) break; if (a_job == NULL) { struct aiocb aiocbp; mutex_exit(&aio->aio_mtx); /* Check if the job is done. */ error = copyin(aiocbp_list[i], &aiocbp, sizeof(struct aiocb)); if (error == 0 && aiocbp._state != JOB_DONE) { mutex_enter(&aio->aio_mtx); continue; } return error; } } /* Wait for a signal or when timeout occurs */ error = cv_timedwait_sig(&aio->done_cv, &aio->aio_mtx, timo); if (error) { if (error == EWOULDBLOCK) error = EAGAIN; break; } } mutex_exit(&aio->aio_mtx); return error; } int sys_aio_write(struct lwp *l, const struct sys_aio_write_args *uap, register_t *retval) { /* { syscallarg(struct aiocb *) aiocbp; } */ return aio_enqueue_job(AIO_WRITE, SCARG(uap, aiocbp), NULL); } int sys_lio_listio(struct lwp *l, const struct sys_lio_listio_args *uap, register_t *retval) { /* { syscallarg(int) mode; syscallarg(struct aiocb *const[]) list; syscallarg(int) nent; syscallarg(struct sigevent *) sig; } */ struct proc *p = l->l_proc; struct aioproc *aio; struct aiocb **aiocbp_list; struct lio_req *lio; int i, error, errcnt, mode, nent; mode = SCARG(uap, mode); nent = SCARG(uap, nent); /* Non-accurate checks for the limit and invalid values */ if (nent < 1 || nent > aio_listio_max) return EINVAL; if (aio_jobs_count + nent > aio_max) return EAGAIN; /* Check if AIO structure is initialized, if not - initialize it */ if (p->p_aio == NULL) if (aio_procinit(p)) return EAGAIN; aio = p->p_aio; /* Create a LIO structure */ lio = pool_get(&aio_lio_pool, PR_WAITOK); lio->refcnt = 1; error = 0; switch (mode) { case LIO_WAIT: memset(&lio->sig, 0, sizeof(struct sigevent)); break; case LIO_NOWAIT: /* Check for signal, validate it */ if (SCARG(uap, sig)) { struct sigevent *sig = &lio->sig; error = copyin(SCARG(uap, sig), &lio->sig, sizeof(struct sigevent)); if (error == 0 && (sig->sigev_signo < 0 || sig->sigev_signo >= NSIG || sig->sigev_notify < SIGEV_NONE || sig->sigev_notify > SIGEV_SA)) error = EINVAL; } else memset(&lio->sig, 0, sizeof(struct sigevent)); break; default: error = EINVAL; break; } if (error != 0) { pool_put(&aio_lio_pool, lio); return error; } /* Get the list from user-space */ aiocbp_list = kmem_alloc(nent * sizeof(*aiocbp_list), KM_SLEEP); error = copyin(SCARG(uap, list), aiocbp_list, nent * sizeof(*aiocbp_list)); if (error) { mutex_enter(&aio->aio_mtx); goto err; } /* Enqueue all jobs */ errcnt = 0; for (i = 0; i < nent; i++) { error = aio_enqueue_job(AIO_LIO, aiocbp_list[i], lio); /* * According to POSIX, in such error case it may * fail with other I/O operations initiated. */ if (error) errcnt++; } mutex_enter(&aio->aio_mtx); /* Return an error, if any */ if (errcnt) { error = EIO; goto err; } if (mode == LIO_WAIT) { /* * Wait for AIO completion. In such case, * the LIO structure will be freed here. */ while (lio->refcnt > 1 && error == 0) error = cv_wait_sig(&aio->done_cv, &aio->aio_mtx); if (error) error = EINTR; } err: if (--lio->refcnt != 0) lio = NULL; mutex_exit(&aio->aio_mtx); if (lio != NULL) { aio_sendsig(p, &lio->sig); pool_put(&aio_lio_pool, lio); } kmem_free(aiocbp_list, nent * sizeof(*aiocbp_list)); return error; } /* * SysCtl */ static int sysctl_aio_listio_max(SYSCTLFN_ARGS) { struct sysctlnode node; int error, newsize; node = *rnode; node.sysctl_data = &newsize; newsize = aio_listio_max; error = sysctl_lookup(SYSCTLFN_CALL(&node)); if (error || newp == NULL) return error; if (newsize < 1 || newsize > aio_max) return EINVAL; aio_listio_max = newsize; return 0; } static int sysctl_aio_max(SYSCTLFN_ARGS) { struct sysctlnode node; int error, newsize; node = *rnode; node.sysctl_data = &newsize; newsize = aio_max; error = sysctl_lookup(SYSCTLFN_CALL(&node)); if (error || newp == NULL) return error; if (newsize < 1 || newsize < aio_listio_max) return EINVAL; aio_max = newsize; return 0; } static int sysctl_aio_init(void) { int rv; aio_sysctl = NULL; rv = sysctl_createv(&aio_sysctl, 0, NULL, NULL, CTLFLAG_PERMANENT | CTLFLAG_IMMEDIATE, CTLTYPE_INT, "posix_aio", SYSCTL_DESCR("Version of IEEE Std 1003.1 and its " "Asynchronous I/O option to which the " "system attempts to conform"), NULL, _POSIX_ASYNCHRONOUS_IO, NULL, 0, CTL_KERN, CTL_CREATE, CTL_EOL); if (rv != 0) return rv; rv = sysctl_createv(&aio_sysctl, 0, NULL, NULL, CTLFLAG_PERMANENT | CTLFLAG_READWRITE, CTLTYPE_INT, "aio_listio_max", SYSCTL_DESCR("Maximum number of asynchronous I/O " "operations in a single list I/O call"), sysctl_aio_listio_max, 0, &aio_listio_max, 0, CTL_KERN, CTL_CREATE, CTL_EOL); if (rv != 0) return rv; rv = sysctl_createv(&aio_sysctl, 0, NULL, NULL, CTLFLAG_PERMANENT | CTLFLAG_READWRITE, CTLTYPE_INT, "aio_max", SYSCTL_DESCR("Maximum number of asynchronous I/O " "operations"), sysctl_aio_max, 0, &aio_max, 0, CTL_KERN, CTL_CREATE, CTL_EOL); return rv; } /* * Debugging */ #if defined(DDB) void aio_print_jobs(void (*pr)(const char *, ...)) { struct proc *p = curlwp->l_proc; struct aioproc *aio; struct aio_job *a_job; struct aiocb *aiocbp; if (p == NULL) { (*pr)("AIO: We are not in the processes right now.\n"); return; } aio = p->p_aio; if (aio == NULL) { (*pr)("AIO data is not initialized (PID = %d).\n", p->p_pid); return; } (*pr)("AIO: PID = %d\n", p->p_pid); (*pr)("AIO: Global count of the jobs = %u\n", aio_jobs_count); (*pr)("AIO: Count of the jobs = %u\n", aio->jobs_count); if (aio->curjob) { a_job = aio->curjob; (*pr)("\nAIO current job:\n"); (*pr)(" opcode = %d, errno = %d, state = %d, aiocb_ptr = %p\n", a_job->aio_op, a_job->aiocbp._errno, a_job->aiocbp._state, a_job->aiocb_uptr); aiocbp = &a_job->aiocbp; (*pr)(" fd = %d, offset = %u, buf = %p, nbytes = %u\n", aiocbp->aio_fildes, aiocbp->aio_offset, aiocbp->aio_buf, aiocbp->aio_nbytes); } (*pr)("\nAIO queue:\n"); TAILQ_FOREACH(a_job, &aio->jobs_queue, list) { (*pr)(" opcode = %d, errno = %d, state = %d, aiocb_ptr = %p\n", a_job->aio_op, a_job->aiocbp._errno, a_job->aiocbp._state, a_job->aiocb_uptr); aiocbp = &a_job->aiocbp; (*pr)(" fd = %d, offset = %u, buf = %p, nbytes = %u\n", aiocbp->aio_fildes, aiocbp->aio_offset, aiocbp->aio_buf, aiocbp->aio_nbytes); } } #endif /* defined(DDB) */