/*-
 * SPDX-License-Identifier: BSD-2-Clause
 *
 * Copyright (c) 1997 John S. Dyson.  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. John S. Dyson's name may not be used to endorse or promote products
 *    derived from this software without specific prior written permission.
 *
 * DISCLAIMER:  This code isn't warranted to do anything useful.  Anything
 * bad that happens because of using this software isn't the responsibility
 * of the author.  This software is distributed AS-IS.
 */

/*
 * This file contains support for the POSIX 1003.1B AIO/LIO facility.
 */

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/malloc.h>
#include <sys/bio.h>
#include <sys/buf.h>
#include <sys/capsicum.h>
#include <sys/eventhandler.h>
#include <sys/sysproto.h>
#include <sys/filedesc.h>
#include <sys/kernel.h>
#include <sys/module.h>
#include <sys/kthread.h>
#include <sys/fcntl.h>
#include <sys/file.h>
#include <sys/limits.h>
#include <sys/lock.h>
#include <sys/mutex.h>
#include <sys/unistd.h>
#include <sys/posix4.h>
#include <sys/proc.h>
#include <sys/resourcevar.h>
#include <sys/signalvar.h>
#include <sys/syscallsubr.h>
#include <sys/protosw.h>
#include <sys/rwlock.h>
#include <sys/sema.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/syscall.h>
#include <sys/sysctl.h>
#include <sys/syslog.h>
#include <sys/sx.h>
#include <sys/taskqueue.h>
#include <sys/vnode.h>
#include <sys/conf.h>
#include <sys/event.h>
#include <sys/mount.h>
#include <geom/geom.h>

#include <machine/atomic.h>

#include <vm/vm.h>
#include <vm/vm_page.h>
#include <vm/vm_extern.h>
#include <vm/pmap.h>
#include <vm/vm_map.h>
#include <vm/vm_object.h>
#include <vm/vnode_pager.h>
#include <vm/uma.h>
#include <sys/aio.h>

/*
 * Counter for aio_fsync.
 */
static uint64_t jobseqno;

#ifndef MAX_AIO_PER_PROC
#define MAX_AIO_PER_PROC        32
#endif

#ifndef MAX_AIO_QUEUE_PER_PROC
#define MAX_AIO_QUEUE_PER_PROC  256
#endif

#ifndef MAX_AIO_QUEUE
#define MAX_AIO_QUEUE           1024 /* Bigger than MAX_AIO_QUEUE_PER_PROC */
#endif

#ifndef MAX_BUF_AIO
#define MAX_BUF_AIO             16
#endif

FEATURE(aio, "Asynchronous I/O");
SYSCTL_DECL(_p1003_1b);

static MALLOC_DEFINE(M_LIO, "lio", "listio aio control block list");
static MALLOC_DEFINE(M_AIO, "aio", "structures for asynchronous I/O");

static SYSCTL_NODE(_vfs, OID_AUTO, aio, CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
    "Async IO management");

static int enable_aio_unsafe = 0;
SYSCTL_INT(_vfs_aio, OID_AUTO, enable_unsafe, CTLFLAG_RW, &enable_aio_unsafe, 0,
    "Permit asynchronous IO on all file types, not just known-safe types");

static unsigned int unsafe_warningcnt = 1;
SYSCTL_UINT(_vfs_aio, OID_AUTO, unsafe_warningcnt, CTLFLAG_RW,
    &unsafe_warningcnt, 0,
    "Warnings that will be triggered upon failed IO requests on unsafe files");

static int max_aio_procs = MAX_AIO_PROCS;
SYSCTL_INT(_vfs_aio, OID_AUTO, max_aio_procs, CTLFLAG_RW, &max_aio_procs, 0,
    "Maximum number of kernel processes to use for handling async IO ");

static int num_aio_procs = 0;
SYSCTL_INT(_vfs_aio, OID_AUTO, num_aio_procs, CTLFLAG_RD, &num_aio_procs, 0,
    "Number of presently active kernel processes for async IO");

/*
 * The code will adjust the actual number of AIO processes towards this
 * number when it gets a chance.
 */
static int target_aio_procs = TARGET_AIO_PROCS;
SYSCTL_INT(_vfs_aio, OID_AUTO, target_aio_procs, CTLFLAG_RW, &target_aio_procs,
    0,
    "Preferred number of ready kernel processes for async IO");

static int max_queue_count = MAX_AIO_QUEUE;
SYSCTL_INT(_vfs_aio, OID_AUTO, max_aio_queue, CTLFLAG_RW, &max_queue_count, 0,
    "Maximum number of aio requests to queue, globally");

static int num_queue_count = 0;
SYSCTL_INT(_vfs_aio, OID_AUTO, num_queue_count, CTLFLAG_RD, &num_queue_count, 0,
    "Number of queued aio requests");

static int num_buf_aio = 0;
SYSCTL_INT(_vfs_aio, OID_AUTO, num_buf_aio, CTLFLAG_RD, &num_buf_aio, 0,
    "Number of aio requests presently handled by the buf subsystem");

static int num_unmapped_aio = 0;
SYSCTL_INT(_vfs_aio, OID_AUTO, num_unmapped_aio, CTLFLAG_RD, &num_unmapped_aio,
    0,
    "Number of aio requests presently handled by unmapped I/O buffers");

/* Number of async I/O processes in the process of being started */
/* XXX This should be local to aio_aqueue() */
static int num_aio_resv_start = 0;

static int aiod_lifetime;
SYSCTL_INT(_vfs_aio, OID_AUTO, aiod_lifetime, CTLFLAG_RW, &aiod_lifetime, 0,
    "Maximum lifetime for idle aiod");

static int max_aio_per_proc = MAX_AIO_PER_PROC;
SYSCTL_INT(_vfs_aio, OID_AUTO, max_aio_per_proc, CTLFLAG_RW, &max_aio_per_proc,
    0,
    "Maximum active aio requests per process");

static int max_aio_queue_per_proc = MAX_AIO_QUEUE_PER_PROC;
SYSCTL_INT(_vfs_aio, OID_AUTO, max_aio_queue_per_proc, CTLFLAG_RW,
    &max_aio_queue_per_proc, 0,
    "Maximum queued aio requests per process");

static int max_buf_aio = MAX_BUF_AIO;
SYSCTL_INT(_vfs_aio, OID_AUTO, max_buf_aio, CTLFLAG_RW, &max_buf_aio, 0,
    "Maximum buf aio requests per process");

/* 
 * Though redundant with vfs.aio.max_aio_queue_per_proc, POSIX requires
 * sysconf(3) to support AIO_LISTIO_MAX, and we implement that with
 * vfs.aio.aio_listio_max.
 */
SYSCTL_INT(_p1003_1b, CTL_P1003_1B_AIO_LISTIO_MAX, aio_listio_max,
    CTLFLAG_RD | CTLFLAG_CAPRD, &max_aio_queue_per_proc,
    0, "Maximum aio requests for a single lio_listio call");

#ifdef COMPAT_FREEBSD6
typedef struct oaiocb {
        int     aio_fildes;             /* File descriptor */
        off_t   aio_offset;             /* File offset for I/O */
        volatile void *aio_buf;         /* I/O buffer in process space */
        size_t  aio_nbytes;             /* Number of bytes for I/O */
        struct  osigevent aio_sigevent; /* Signal to deliver */
        int     aio_lio_opcode;         /* LIO opcode */
        int     aio_reqprio;            /* Request priority -- ignored */
        struct  __aiocb_private _aiocb_private;
} oaiocb_t;
#endif

/*
 * Below is a key of locks used to protect each member of struct kaiocb
 * aioliojob and kaioinfo and any backends.
 *
 * * - need not protected
 * a - locked by kaioinfo lock
 * b - locked by backend lock, the backend lock can be null in some cases,
 *     for example, BIO belongs to this type, in this case, proc lock is
 *     reused.
 * c - locked by aio_job_mtx, the lock for the generic file I/O backend.
 */

/*
 * If the routine that services an AIO request blocks while running in an
 * AIO kernel process it can starve other I/O requests.  BIO requests
 * queued via aio_qbio() complete asynchronously and do not use AIO kernel
 * processes at all.  Socket I/O requests use a separate pool of
 * kprocs and also force non-blocking I/O.  Other file I/O requests
 * use the generic fo_read/fo_write operations which can block.  The
 * fsync and mlock operations can also block while executing.  Ideally
 * none of these requests would block while executing.
 *
 * Note that the service routines cannot toggle O_NONBLOCK in the file
 * structure directly while handling a request due to races with
 * userland threads.
 */

/* jobflags */
#define KAIOCB_QUEUEING         0x01
#define KAIOCB_CANCELLED        0x02
#define KAIOCB_CANCELLING       0x04
#define KAIOCB_CHECKSYNC        0x08
#define KAIOCB_CLEARED          0x10
#define KAIOCB_FINISHED         0x20
#define KAIOCB_MARKER           0x40

/* ioflags */
#define KAIOCB_IO_FOFFSET       0x01

/*
 * AIO process info
 */
#define AIOP_FREE       0x1                     /* proc on free queue */

struct aioproc {
        int     aioprocflags;                   /* (c) AIO proc flags */
        TAILQ_ENTRY(aioproc) list;              /* (c) list of processes */
        struct  proc *aioproc;                  /* (*) the AIO proc */
};

/*
 * data-structure for lio signal management
 */
struct aioliojob {
        int     lioj_flags;                     /* (a) listio flags */
        int     lioj_count;                     /* (a) count of jobs */
        int     lioj_finished_count;            /* (a) count of finished jobs */
        struct  sigevent lioj_signal;           /* (a) signal on all I/O done */
        TAILQ_ENTRY(aioliojob) lioj_list;       /* (a) lio list */
        struct  knlist klist;                   /* (a) list of knotes */
        ksiginfo_t lioj_ksi;                    /* (a) Realtime signal info */
};

#define LIOJ_SIGNAL             0x1     /* signal on all done (lio) */
#define LIOJ_SIGNAL_POSTED      0x2     /* signal has been posted */
#define LIOJ_KEVENT_POSTED      0x4     /* kevent triggered */

/*
 * per process aio data structure
 */
struct kaioinfo {
        struct  mtx kaio_mtx;           /* the lock to protect this struct */
        int     kaio_flags;             /* (a) per process kaio flags */
        int     kaio_active_count;      /* (c) number of currently used AIOs */
        int     kaio_count;             /* (a) size of AIO queue */
        int     kaio_buffer_count;      /* (a) number of bio buffers */
        TAILQ_HEAD(,kaiocb) kaio_all;   /* (a) all AIOs in a process */
        TAILQ_HEAD(,kaiocb) kaio_done;  /* (a) done queue for process */
        TAILQ_HEAD(,aioliojob) kaio_liojoblist; /* (a) list of lio jobs */
        TAILQ_HEAD(,kaiocb) kaio_jobqueue;      /* (a) job queue for process */
        TAILQ_HEAD(,kaiocb) kaio_syncqueue;     /* (a) queue for aio_fsync */
        TAILQ_HEAD(,kaiocb) kaio_syncready;  /* (a) second q for aio_fsync */
        struct  task kaio_task;         /* (*) task to kick aio processes */
        struct  task kaio_sync_task;    /* (*) task to schedule fsync jobs */
};

#define AIO_LOCK(ki)            mtx_lock(&(ki)->kaio_mtx)
#define AIO_UNLOCK(ki)          mtx_unlock(&(ki)->kaio_mtx)
#define AIO_LOCK_ASSERT(ki, f)  mtx_assert(&(ki)->kaio_mtx, (f))
#define AIO_MTX(ki)             (&(ki)->kaio_mtx)

#define KAIO_RUNDOWN    0x1     /* process is being run down */
#define KAIO_WAKEUP     0x2     /* wakeup process when AIO completes */

/*
 * Operations used to interact with userland aio control blocks.
 * Different ABIs provide their own operations.
 */
struct aiocb_ops {
        int     (*aio_copyin)(struct aiocb *ujob, struct kaiocb *kjob, int ty);
        long    (*fetch_status)(struct aiocb *ujob);
        long    (*fetch_error)(struct aiocb *ujob);
        int     (*store_status)(struct aiocb *ujob, long status);
        int     (*store_error)(struct aiocb *ujob, long error);
        int     (*store_aiocb)(struct aiocb **ujobp, struct aiocb *ujob);
};

static TAILQ_HEAD(,aioproc) aio_freeproc;               /* (c) Idle daemons */
static struct sema aio_newproc_sem;
static struct mtx aio_job_mtx;
static TAILQ_HEAD(,kaiocb) aio_jobs;                    /* (c) Async job list */
static struct unrhdr *aiod_unr;

static void     aio_biocleanup(struct bio *bp);
static int      aio_init_aioinfo(struct proc *p);
static int      aio_onceonly(void);
static int      aio_free_entry(struct kaiocb *job);
static void     aio_process_rw(struct kaiocb *job);
static void     aio_process_sync(struct kaiocb *job);
static void     aio_process_mlock(struct kaiocb *job);
static void     aio_schedule_fsync(void *context, int pending);
static int      aio_newproc(int *);
static int      aio_aqueue(struct thread *td, struct aiocb *ujob,
                    struct aioliojob *lio, int type, struct aiocb_ops *ops);
static int      aio_queue_file(struct file *fp, struct kaiocb *job);
static void     aio_biowakeup(struct bio *bp);
static void     aio_proc_rundown(void *arg, struct proc *p);
static void     aio_proc_rundown_exec(void *arg, struct proc *p,
                    struct image_params *imgp);
static int      aio_qbio(struct proc *p, struct kaiocb *job);
static void     aio_daemon(void *param);
static void     aio_bio_done_notify(struct proc *userp, struct kaiocb *job);
static bool     aio_clear_cancel_function_locked(struct kaiocb *job);
static int      aio_kick(struct proc *userp);
static void     aio_kick_nowait(struct proc *userp);
static void     aio_kick_helper(void *context, int pending);
static int      filt_aioattach(struct knote *kn);
static void     filt_aiodetach(struct knote *kn);
static int      filt_aio(struct knote *kn, long hint);
static int      filt_lioattach(struct knote *kn);
static void     filt_liodetach(struct knote *kn);
static int      filt_lio(struct knote *kn, long hint);

/*
 * Zones for:
 *      kaio    Per process async io info
 *      aiocb   async io jobs
 *      aiolio  list io jobs
 */
static uma_zone_t kaio_zone, aiocb_zone, aiolio_zone;

/* kqueue filters for aio */
static const struct filterops aio_filtops = {
        .f_isfd = 0,
        .f_attach = filt_aioattach,
        .f_detach = filt_aiodetach,
        .f_event = filt_aio,
        .f_copy = knote_triv_copy,
};
static const struct filterops lio_filtops = {
        .f_isfd = 0,
        .f_attach = filt_lioattach,
        .f_detach = filt_liodetach,
        .f_event = filt_lio,
        .f_copy = knote_triv_copy,
};

static eventhandler_tag exit_tag, exec_tag;

TASKQUEUE_DEFINE_THREAD(aiod_kick);

/*
 * Main operations function for use as a kernel module.
 */
static int
aio_modload(struct module *module, int cmd, void *arg)
{
        int error = 0;

        switch (cmd) {
        case MOD_LOAD:
                aio_onceonly();
                break;
        case MOD_SHUTDOWN:
                break;
        default:
                error = EOPNOTSUPP;
                break;
        }
        return (error);
}

static moduledata_t aio_mod = {
        "aio",
        &aio_modload,
        NULL
};

DECLARE_MODULE(aio, aio_mod, SI_SUB_VFS, SI_ORDER_ANY);
MODULE_VERSION(aio, 1);

/*
 * Startup initialization
 */
static int
aio_onceonly(void)
{

        exit_tag = EVENTHANDLER_REGISTER(process_exit, aio_proc_rundown, NULL,
            EVENTHANDLER_PRI_ANY);
        exec_tag = EVENTHANDLER_REGISTER(process_exec, aio_proc_rundown_exec,
            NULL, EVENTHANDLER_PRI_ANY);
        kqueue_add_filteropts(EVFILT_AIO, &aio_filtops);
        kqueue_add_filteropts(EVFILT_LIO, &lio_filtops);
        TAILQ_INIT(&aio_freeproc);
        sema_init(&aio_newproc_sem, 0, "aio_new_proc");
        mtx_init(&aio_job_mtx, "aio_job", NULL, MTX_DEF);
        TAILQ_INIT(&aio_jobs);
        aiod_unr = new_unrhdr(1, INT_MAX, NULL);
        kaio_zone = uma_zcreate("AIO", sizeof(struct kaioinfo), NULL, NULL,
            NULL, NULL, UMA_ALIGN_PTR, 0);
        aiocb_zone = uma_zcreate("AIOCB", sizeof(struct kaiocb), NULL, NULL,
            NULL, NULL, UMA_ALIGN_PTR, 0);
        aiolio_zone = uma_zcreate("AIOLIO", sizeof(struct aioliojob), NULL,
            NULL, NULL, NULL, UMA_ALIGN_PTR, 0);
        aiod_lifetime = AIOD_LIFETIME_DEFAULT;
        p31b_setcfg(CTL_P1003_1B_ASYNCHRONOUS_IO, _POSIX_ASYNCHRONOUS_IO);
        p31b_setcfg(CTL_P1003_1B_AIO_MAX, MAX_AIO_QUEUE);
        p31b_setcfg(CTL_P1003_1B_AIO_PRIO_DELTA_MAX, 0);

        return (0);
}

/*
 * Init the per-process aioinfo structure.  The aioinfo limits are set
 * per-process for user limit (resource) management.
 */
static int
aio_init_aioinfo(struct proc *p)
{
        struct kaioinfo *ki;
        int error;

        ki = uma_zalloc(kaio_zone, M_WAITOK);
        mtx_init(&ki->kaio_mtx, "aiomtx", NULL, MTX_DEF | MTX_NEW);
        ki->kaio_flags = 0;
        ki->kaio_active_count = 0;
        ki->kaio_count = 0;
        ki->kaio_buffer_count = 0;
        TAILQ_INIT(&ki->kaio_all);
        TAILQ_INIT(&ki->kaio_done);
        TAILQ_INIT(&ki->kaio_jobqueue);
        TAILQ_INIT(&ki->kaio_liojoblist);
        TAILQ_INIT(&ki->kaio_syncqueue);
        TAILQ_INIT(&ki->kaio_syncready);
        TASK_INIT(&ki->kaio_task, 0, aio_kick_helper, p);
        TASK_INIT(&ki->kaio_sync_task, 0, aio_schedule_fsync, ki);
        PROC_LOCK(p);
        if (p->p_aioinfo == NULL) {
                p->p_aioinfo = ki;
                PROC_UNLOCK(p);
        } else {
                PROC_UNLOCK(p);
                mtx_destroy(&ki->kaio_mtx);
                uma_zfree(kaio_zone, ki);
        }

        error = 0;
        while (num_aio_procs < MIN(target_aio_procs, max_aio_procs)) {
                error = aio_newproc(NULL);
                if (error != 0) {
                        /*
                         * At least one worker is enough to have AIO
                         * functional.  Clear error in that case.
                         */
                        if (num_aio_procs > 0)
                                error = 0;
                        break;
                }
        }
        return (error);
}

static int
aio_sendsig(struct proc *p, struct sigevent *sigev, ksiginfo_t *ksi, bool ext)
{
        struct thread *td;
        int error;

        error = sigev_findtd(p, sigev, &td);
        if (error)
                return (error);
        if (!KSI_ONQ(ksi)) {
                ksiginfo_set_sigev(ksi, sigev);
                ksi->ksi_code = SI_ASYNCIO;
                ksi->ksi_flags |= ext ? (KSI_EXT | KSI_INS) : 0;
                tdsendsignal(p, td, ksi->ksi_signo, ksi);
        }
        PROC_UNLOCK(p);
        return (error);
}

/*
 * Free a job entry.  Wait for completion if it is currently active, but don't
 * delay forever.  If we delay, we return a flag that says that we have to
 * restart the queue scan.
 */
static int
aio_free_entry(struct kaiocb *job)
{
        struct kaioinfo *ki;
        struct aioliojob *lj;
        struct proc *p;

        p = job->userproc;
        MPASS(curproc == p);
        ki = p->p_aioinfo;
        MPASS(ki != NULL);

        AIO_LOCK_ASSERT(ki, MA_OWNED);
        MPASS(job->jobflags & KAIOCB_FINISHED);

        atomic_subtract_int(&num_queue_count, 1);

        ki->kaio_count--;
        MPASS(ki->kaio_count >= 0);

        TAILQ_REMOVE(&ki->kaio_done, job, plist);
        TAILQ_REMOVE(&ki->kaio_all, job, allist);

        lj = job->lio;
        if (lj) {
                lj->lioj_count--;
                lj->lioj_finished_count--;

                if (lj->lioj_count == 0) {
                        TAILQ_REMOVE(&ki->kaio_liojoblist, lj, lioj_list);
                        /* lio is going away, we need to destroy any knotes */
                        knlist_delete(&lj->klist, curthread, 1);
                        PROC_LOCK(p);
                        sigqueue_take(&lj->lioj_ksi);
                        PROC_UNLOCK(p);
                        uma_zfree(aiolio_zone, lj);
                }
        }

        /* job is going away, we need to destroy any knotes */
        knlist_delete(&job->klist, curthread, 1);
        PROC_LOCK(p);
        sigqueue_take(&job->ksi);
        PROC_UNLOCK(p);

        AIO_UNLOCK(ki);

        /*
         * The thread argument here is used to find the owning process
         * and is also passed to fo_close() which may pass it to various
         * places such as devsw close() routines.  Because of that, we
         * need a thread pointer from the process owning the job that is
         * persistent and won't disappear out from under us or move to
         * another process.
         *
         * Currently, all the callers of this function call it to remove
         * a kaiocb from the current process' job list either via a
         * syscall or due to the current process calling exit() or
         * execve().  Thus, we know that p == curproc.  We also know that
         * curthread can't exit since we are curthread.
         *
         * Therefore, we use curthread as the thread to pass to
         * knlist_delete().  This does mean that it is possible for the
         * thread pointer at close time to differ from the thread pointer
         * at open time, but this is already true of file descriptors in
         * a multithreaded process.
         */
        if (job->fd_file)
                fdrop(job->fd_file, curthread);
        crfree(job->cred);
        if (job->uiop != &job->uio)
                freeuio(job->uiop);
        uma_zfree(aiocb_zone, job);
        AIO_LOCK(ki);

        return (0);
}

static void
aio_proc_rundown_exec(void *arg, struct proc *p,
    struct image_params *imgp __unused)
{
        aio_proc_rundown(arg, p);
}

static int
aio_cancel_job(struct proc *p, struct kaioinfo *ki, struct kaiocb *job)
{
        aio_cancel_fn_t *func;
        int cancelled;

        AIO_LOCK_ASSERT(ki, MA_OWNED);

        /*
         * If we're running down the queue, the process must be single-threaded,
         * and so no markers should be present.
         */
        MPASS((job->jobflags & KAIOCB_MARKER) == 0);
        if (job->jobflags & (KAIOCB_CANCELLED | KAIOCB_FINISHED))
                return (0);
        MPASS((job->jobflags & KAIOCB_CANCELLING) == 0);
        job->jobflags |= KAIOCB_CANCELLED;

        func = job->cancel_fn;

        /*
         * If there is no cancel routine, just leave the job marked as
         * cancelled.  The job should be in active use by a caller who
         * should complete it normally or when it fails to install a
         * cancel routine.
         */
        if (func == NULL)
                return (0);

        /*
         * Set the CANCELLING flag so that aio_complete() will defer
         * completions of this job.  This prevents the job from being
         * freed out from under the cancel callback.  After the
         * callback any deferred completion (whether from the callback
         * or any other source) will be completed.
         */
        job->jobflags |= KAIOCB_CANCELLING;
        AIO_UNLOCK(ki);
        func(job);
        AIO_LOCK(ki);
        job->jobflags &= ~KAIOCB_CANCELLING;
        if (job->jobflags & KAIOCB_FINISHED) {
                cancelled = job->uaiocb._aiocb_private.error == ECANCELED;
                TAILQ_REMOVE(&ki->kaio_jobqueue, job, plist);
                aio_bio_done_notify(p, job);
        } else {
                /*
                 * The cancel callback might have scheduled an
                 * operation to cancel this request, but it is
                 * only counted as cancelled if the request is
                 * cancelled when the callback returns.
                 */
                cancelled = 0;
        }
        return (cancelled);
}

/*
 * Rundown the jobs for a given process.
 */
static void
aio_proc_rundown(void *arg, struct proc *p)
{
        struct kaioinfo *ki;
        struct aioliojob *lj;
        struct kaiocb *job, *jobn;

        KASSERT(curthread->td_proc == p,
            ("%s: called on non-curproc", __func__));
        ki = p->p_aioinfo;
        if (ki == NULL)
                return;

        AIO_LOCK(ki);
        ki->kaio_flags |= KAIO_RUNDOWN;

restart:

        /*
         * Try to cancel all pending requests. This code simulates
         * aio_cancel on all pending I/O requests.
         */
        TAILQ_FOREACH_SAFE(job, &ki->kaio_jobqueue, plist, jobn) {
                aio_cancel_job(p, ki, job);
        }

        /* Wait for all running I/O to be finished */
        if (!TAILQ_EMPTY(&ki->kaio_jobqueue) || ki->kaio_active_count != 0) {
                ki->kaio_flags |= KAIO_WAKEUP;
                msleep(&p->p_aioinfo, AIO_MTX(ki), PRIBIO, "aioprn", hz);
                goto restart;
        }

        /* Free all completed I/O requests. */
        while ((job = TAILQ_FIRST(&ki->kaio_done)) != NULL)
                aio_free_entry(job);

        while ((lj = TAILQ_FIRST(&ki->kaio_liojoblist)) != NULL) {
                if (lj->lioj_count == 0) {
                        TAILQ_REMOVE(&ki->kaio_liojoblist, lj, lioj_list);
                        knlist_delete(&lj->klist, curthread, 1);
                        PROC_LOCK(p);
                        sigqueue_take(&lj->lioj_ksi);
                        PROC_UNLOCK(p);
                        uma_zfree(aiolio_zone, lj);
                } else {
                        panic("LIO job not cleaned up: C:%d, FC:%d\n",
                            lj->lioj_count, lj->lioj_finished_count);
                }
        }
        AIO_UNLOCK(ki);
        taskqueue_drain(taskqueue_aiod_kick, &ki->kaio_task);
        taskqueue_drain(taskqueue_aiod_kick, &ki->kaio_sync_task);
        mtx_destroy(&ki->kaio_mtx);
        uma_zfree(kaio_zone, ki);
        p->p_aioinfo = NULL;
}

/*
 * Select a job to run (called by an AIO daemon).
 */
static struct kaiocb *
aio_selectjob(struct aioproc *aiop)
{
        struct kaiocb *job;
        struct kaioinfo *ki;
        struct proc *userp;

        mtx_assert(&aio_job_mtx, MA_OWNED);
restart:
        TAILQ_FOREACH(job, &aio_jobs, list) {
                userp = job->userproc;
                ki = userp->p_aioinfo;

                if (ki->kaio_active_count < max_aio_per_proc) {
                        TAILQ_REMOVE(&aio_jobs, job, list);
                        if (!aio_clear_cancel_function(job))
                                goto restart;

                        /* Account for currently active jobs. */
                        ki->kaio_active_count++;
                        break;
                }
        }
        return (job);
}

/*
 * Move all data to a permanent storage device.  This code
 * simulates the fsync and fdatasync syscalls.
 */
static int
aio_fsync_vnode(struct thread *td, struct vnode *vp, int op)
{
        struct mount *mp;
        int error;

        for (;;) {
                error = vn_start_write(vp, &mp, V_WAIT | V_PCATCH);
                if (error != 0)
                        break;
                vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
                vnode_pager_clean_async(vp);
                if (op == LIO_DSYNC)
                        error = VOP_FDATASYNC(vp, td);
                else
                        error = VOP_FSYNC(vp, MNT_WAIT, td);

                VOP_UNLOCK(vp);
                vn_finished_write(mp);
                if (error != ERELOOKUP)
                        break;
        }
        return (error);
}

/*
 * The AIO processing activity for LIO_READ/LIO_WRITE.  This is the code that
 * does the I/O request for the non-bio version of the operations.  The normal
 * vn operations are used, and this code should work in all instances for every
 * type of file, including pipes, sockets, fifos, and regular files.
 *
 * XXX I don't think it works well for socket, pipe, and fifo.
 */
static void
aio_process_rw(struct kaiocb *job)
{
        struct ucred *td_savedcred;
        struct thread *td;
        struct file *fp;
        ssize_t cnt;
        long msgsnd_st, msgsnd_end;
        long msgrcv_st, msgrcv_end;
        long oublock_st, oublock_end;
        long inblock_st, inblock_end;
        int error, opcode;

        opcode = job->uaiocb.aio_lio_opcode & ~LIO_FOFFSET;
        KASSERT(opcode == LIO_READ || opcode == LIO_READV ||
            opcode == LIO_WRITE || opcode == LIO_WRITEV,
            ("%s: opcode %d", __func__, job->uaiocb.aio_lio_opcode));

        aio_switch_vmspace(job);
        td = curthread;
        td_savedcred = td->td_ucred;
        td->td_ucred = job->cred;
        job->uiop->uio_td = td;
        fp = job->fd_file;

        cnt = job->uiop->uio_resid;

        msgrcv_st = td->td_ru.ru_msgrcv;
        msgsnd_st = td->td_ru.ru_msgsnd;
        inblock_st = td->td_ru.ru_inblock;
        oublock_st = td->td_ru.ru_oublock;

        /*
         * aio_aqueue() acquires a reference to the file that is
         * released in aio_free_entry().
         */
        if (opcode == LIO_READ || opcode == LIO_READV) {
                if (job->uiop->uio_resid == 0)
                        error = 0;
                else
                        error = fo_read(fp, job->uiop, fp->f_cred,
                            (job->ioflags & KAIOCB_IO_FOFFSET) != 0 ? 0 :
                            FOF_OFFSET, td);
        } else {
                if (fp->f_type == DTYPE_VNODE)
                        bwillwrite();
                error = fo_write(fp, job->uiop, fp->f_cred, (job->ioflags &
                    KAIOCB_IO_FOFFSET) != 0 ? 0 : FOF_OFFSET, td);
        }
        msgrcv_end = td->td_ru.ru_msgrcv;
        msgsnd_end = td->td_ru.ru_msgsnd;
        inblock_end = td->td_ru.ru_inblock;
        oublock_end = td->td_ru.ru_oublock;

        job->msgrcv = msgrcv_end - msgrcv_st;
        job->msgsnd = msgsnd_end - msgsnd_st;
        job->inblock = inblock_end - inblock_st;
        job->outblock = oublock_end - oublock_st;

        if (error != 0 && job->uiop->uio_resid != cnt) {
                if (error == ERESTART || error == EINTR || error == EWOULDBLOCK)
                        error = 0;
                if (error == EPIPE && (opcode & LIO_WRITE)) {
                        PROC_LOCK(job->userproc);
                        kern_psignal(job->userproc, SIGPIPE);
                        PROC_UNLOCK(job->userproc);
                }
        }

        cnt -= job->uiop->uio_resid;
        td->td_ucred = td_savedcred;
        if (error)
                aio_complete(job, -1, error);
        else
                aio_complete(job, cnt, 0);
}

static void
aio_process_sync(struct kaiocb *job)
{
        struct thread *td = curthread;
        struct ucred *td_savedcred = td->td_ucred;
        struct file *fp = job->fd_file;
        int error = 0;

        KASSERT(job->uaiocb.aio_lio_opcode & LIO_SYNC,
            ("%s: opcode %d", __func__, job->uaiocb.aio_lio_opcode));

        td->td_ucred = job->cred;
        if (fp->f_vnode != NULL) {
                error = aio_fsync_vnode(td, fp->f_vnode,
                    job->uaiocb.aio_lio_opcode);
        }
        td->td_ucred = td_savedcred;
        if (error)
                aio_complete(job, -1, error);
        else
                aio_complete(job, 0, 0);
}

static void
aio_process_mlock(struct kaiocb *job)
{
        struct aiocb *cb = &job->uaiocb;
        int error;

        KASSERT(job->uaiocb.aio_lio_opcode == LIO_MLOCK,
            ("%s: opcode %d", __func__, job->uaiocb.aio_lio_opcode));

        aio_switch_vmspace(job);
        error = kern_mlock(job->userproc, job->cred,
            __DEVOLATILE(uintptr_t, cb->aio_buf), cb->aio_nbytes);
        aio_complete(job, error != 0 ? -1 : 0, error);
}

static void
aio_bio_done_notify(struct proc *userp, struct kaiocb *job)
{
        struct aioliojob *lj;
        struct kaioinfo *ki;
        struct kaiocb *sjob, *sjobn;
        int lj_done;
        bool schedule_fsync;

        ki = userp->p_aioinfo;
        AIO_LOCK_ASSERT(ki, MA_OWNED);
        lj = job->lio;
        lj_done = 0;
        if (lj) {
                lj->lioj_finished_count++;
                if (lj->lioj_count == lj->lioj_finished_count)
                        lj_done = 1;
        }
        TAILQ_INSERT_TAIL(&ki->kaio_done, job, plist);
        MPASS(job->jobflags & KAIOCB_FINISHED);

        if (ki->kaio_flags & KAIO_RUNDOWN)
                goto notification_done;

        if (job->uaiocb.aio_sigevent.sigev_notify == SIGEV_SIGNAL ||
            job->uaiocb.aio_sigevent.sigev_notify == SIGEV_THREAD_ID)
                aio_sendsig(userp, &job->uaiocb.aio_sigevent, &job->ksi, true);

        KNOTE_LOCKED(&job->klist, 1);

        if (lj_done) {
                if (lj->lioj_signal.sigev_notify == SIGEV_KEVENT) {
                        lj->lioj_flags |= LIOJ_KEVENT_POSTED;
                        KNOTE_LOCKED(&lj->klist, 1);
                }
                if ((lj->lioj_flags & (LIOJ_SIGNAL | LIOJ_SIGNAL_POSTED))
                    == LIOJ_SIGNAL &&
                    (lj->lioj_signal.sigev_notify == SIGEV_SIGNAL ||
                    lj->lioj_signal.sigev_notify == SIGEV_THREAD_ID)) {
                        aio_sendsig(userp, &lj->lioj_signal, &lj->lioj_ksi,
                            true);
                        lj->lioj_flags |= LIOJ_SIGNAL_POSTED;
                }
        }

notification_done:
        if (job->jobflags & KAIOCB_CHECKSYNC) {
                schedule_fsync = false;
                TAILQ_FOREACH_SAFE(sjob, &ki->kaio_syncqueue, list, sjobn) {
                        if (job->fd_file != sjob->fd_file ||
                            job->seqno >= sjob->seqno)
                                continue;
                        if (--sjob->pending > 0)
                                continue;
                        TAILQ_REMOVE(&ki->kaio_syncqueue, sjob, list);
                        if (!aio_clear_cancel_function_locked(sjob))
                                continue;
                        TAILQ_INSERT_TAIL(&ki->kaio_syncready, sjob, list);
                        schedule_fsync = true;
                }
                if (schedule_fsync)
                        taskqueue_enqueue(taskqueue_aiod_kick,
                            &ki->kaio_sync_task);
        }
        if (ki->kaio_flags & KAIO_WAKEUP) {
                ki->kaio_flags &= ~KAIO_WAKEUP;
                wakeup(&userp->p_aioinfo);
        }
}

static void
aio_schedule_fsync(void *context, int pending)
{
        struct kaioinfo *ki;
        struct kaiocb *job;

        ki = context;
        AIO_LOCK(ki);
        while (!TAILQ_EMPTY(&ki->kaio_syncready)) {
                job = TAILQ_FIRST(&ki->kaio_syncready);
                TAILQ_REMOVE(&ki->kaio_syncready, job, list);
                AIO_UNLOCK(ki);
                aio_schedule(job, aio_process_sync);
                AIO_LOCK(ki);
        }
        AIO_UNLOCK(ki);
}

bool
aio_cancel_cleared(struct kaiocb *job)
{

        /*
         * The caller should hold the same queue lock held when
         * aio_clear_cancel_function() was called and set this flag
         * ensuring this check sees an up-to-date value.  However,
         * there is no way to assert that.
         */
        return ((job->jobflags & KAIOCB_CLEARED) != 0);
}

static bool
aio_clear_cancel_function_locked(struct kaiocb *job)
{

        AIO_LOCK_ASSERT(job->userproc->p_aioinfo, MA_OWNED);
        MPASS(job->cancel_fn != NULL);
        if (job->jobflags & KAIOCB_CANCELLING) {
                job->jobflags |= KAIOCB_CLEARED;
                return (false);
        }
        job->cancel_fn = NULL;
        return (true);
}

bool
aio_clear_cancel_function(struct kaiocb *job)
{
        struct kaioinfo *ki;
        bool ret;

        ki = job->userproc->p_aioinfo;
        AIO_LOCK(ki);
        ret = aio_clear_cancel_function_locked(job);
        AIO_UNLOCK(ki);
        return (ret);
}

static bool
aio_set_cancel_function_locked(struct kaiocb *job, aio_cancel_fn_t *func)
{

        AIO_LOCK_ASSERT(job->userproc->p_aioinfo, MA_OWNED);
        if (job->jobflags & KAIOCB_CANCELLED)
                return (false);
        job->cancel_fn = func;
        return (true);
}

bool
aio_set_cancel_function(struct kaiocb *job, aio_cancel_fn_t *func)
{
        struct kaioinfo *ki;
        bool ret;

        ki = job->userproc->p_aioinfo;
        AIO_LOCK(ki);
        ret = aio_set_cancel_function_locked(job, func);
        AIO_UNLOCK(ki);
        return (ret);
}

void
aio_complete(struct kaiocb *job, long status, int error)
{
        struct kaioinfo *ki;
        struct proc *userp;

        job->uaiocb._aiocb_private.error = error;
        job->uaiocb._aiocb_private.status = status;

        userp = job->userproc;
        ki = userp->p_aioinfo;

        AIO_LOCK(ki);
        KASSERT(!(job->jobflags & KAIOCB_FINISHED),
            ("duplicate aio_complete"));
        job->jobflags |= KAIOCB_FINISHED;
        if ((job->jobflags & (KAIOCB_QUEUEING | KAIOCB_CANCELLING)) == 0) {
                TAILQ_REMOVE(&ki->kaio_jobqueue, job, plist);
                aio_bio_done_notify(userp, job);
        }
        AIO_UNLOCK(ki);
}

void
aio_cancel(struct kaiocb *job)
{

        aio_complete(job, -1, ECANCELED);
}

void
aio_switch_vmspace(struct kaiocb *job)
{

        vmspace_switch_aio(job->userproc->p_vmspace);
}

/*
 * The AIO daemon, most of the actual work is done in aio_process_*,
 * but the setup (and address space mgmt) is done in this routine.
 */
static void
aio_daemon(void *_id)
{
        struct kaiocb *job;
        struct aioproc *aiop;
        struct kaioinfo *ki;
        struct proc *p;
        struct vmspace *myvm;
        struct thread *td = curthread;
        int id = (intptr_t)_id;

        /*
         * Grab an extra reference on the daemon's vmspace so that it
         * doesn't get freed by jobs that switch to a different
         * vmspace.
         */
        p = td->td_proc;
        myvm = vmspace_acquire_ref(p);

        KASSERT(p->p_textvp == NULL, ("kthread has a textvp"));

        /*
         * Allocate and ready the aio control info.  There is one aiop structure
         * per daemon.
         */
        aiop = malloc(sizeof(*aiop), M_AIO, M_WAITOK);
        aiop->aioproc = p;
        aiop->aioprocflags = 0;

        /*
         * Wakeup parent process.  (Parent sleeps to keep from blasting away
         * and creating too many daemons.)
         */
        sema_post(&aio_newproc_sem);

        mtx_lock(&aio_job_mtx);
        for (;;) {
                /*
                 * Take daemon off of free queue
                 */
                if (aiop->aioprocflags & AIOP_FREE) {
                        TAILQ_REMOVE(&aio_freeproc, aiop, list);
                        aiop->aioprocflags &= ~AIOP_FREE;
                }

                /*
                 * Check for jobs.
                 */
                while ((job = aio_selectjob(aiop)) != NULL) {
                        mtx_unlock(&aio_job_mtx);

                        ki = job->userproc->p_aioinfo;
                        job->handle_fn(job);

                        mtx_lock(&aio_job_mtx);
                        /* Decrement the active job count. */
                        ki->kaio_active_count--;
                }

                /*
                 * Disconnect from user address space.
                 */
                if (p->p_vmspace != myvm) {
                        mtx_unlock(&aio_job_mtx);
                        vmspace_switch_aio(myvm);
                        mtx_lock(&aio_job_mtx);
                        /*
                         * We have to restart to avoid race, we only sleep if
                         * no job can be selected.
                         */
                        continue;
                }

                mtx_assert(&aio_job_mtx, MA_OWNED);

                TAILQ_INSERT_HEAD(&aio_freeproc, aiop, list);
                aiop->aioprocflags |= AIOP_FREE;

                /*
                 * If daemon is inactive for a long time, allow it to exit,
                 * thereby freeing resources.
                 */
                if (msleep(p, &aio_job_mtx, PRIBIO, "aiordy",
                    aiod_lifetime) == EWOULDBLOCK && TAILQ_EMPTY(&aio_jobs) &&
                    (aiop->aioprocflags & AIOP_FREE) &&
                    num_aio_procs > target_aio_procs)
                        break;
        }
        TAILQ_REMOVE(&aio_freeproc, aiop, list);
        num_aio_procs--;
        mtx_unlock(&aio_job_mtx);
        free(aiop, M_AIO);
        free_unr(aiod_unr, id);
        vmspace_free(myvm);

        KASSERT(p->p_vmspace == myvm,
            ("AIOD: bad vmspace for exiting daemon"));
        KASSERT(refcount_load(&myvm->vm_refcnt) > 1,
            ("AIOD: bad vm refcnt for exiting daemon: %d",
            refcount_load(&myvm->vm_refcnt)));
        kproc_exit(0);
}

/*
 * Create a new AIO daemon. This is mostly a kernel-thread fork routine. The
 * AIO daemon modifies its environment itself.
 */
static int
aio_newproc(int *start)
{
        int error;
        struct proc *p;
        int id;

        id = alloc_unr(aiod_unr);
        error = kproc_create(aio_daemon, (void *)(intptr_t)id, &p,
                RFNOWAIT, 0, "aiod%d", id);
        if (error == 0) {
                /*
                 * Wait until daemon is started.
                 */
                sema_wait(&aio_newproc_sem);
                mtx_lock(&aio_job_mtx);
                num_aio_procs++;
                if (start != NULL)
                        (*start)--;
                mtx_unlock(&aio_job_mtx);
        } else {
                free_unr(aiod_unr, id);
        }
        return (error);
}

/*
 * Try the high-performance, low-overhead bio method for eligible
 * VCHR devices.  This method doesn't use an aio helper thread, and
 * thus has very low overhead.
 *
 * Assumes that the caller, aio_aqueue(), has incremented the file
 * structure's reference count, preventing its deallocation for the
 * duration of this call.
 */
static int
aio_qbio(struct proc *p, struct kaiocb *job)
{
        struct aiocb *cb;
        struct file *fp;
        struct buf *pbuf;
        struct vnode *vp;
        struct cdevsw *csw;
        struct cdev *dev;
        struct kaioinfo *ki;
        struct bio **bios = NULL;
        off_t offset;
        int bio_cmd, error, i, iovcnt, opcode, poff, ref;
        vm_prot_t prot;
        bool use_unmapped;

        cb = &job->uaiocb;
        fp = job->fd_file;
        opcode = cb->aio_lio_opcode;

        if (!(opcode == LIO_WRITE || opcode == LIO_WRITEV ||
            opcode == LIO_READ || opcode == LIO_READV))
                return (-1);
        if (fp == NULL || fp->f_type != DTYPE_VNODE)
                return (-1);

        vp = fp->f_vnode;
        if (vp->v_type != VCHR)
                return (-1);
        if (vp->v_bufobj.bo_bsize == 0)
                return (-1);

        bio_cmd = (opcode & LIO_WRITE) ? BIO_WRITE : BIO_READ;
        iovcnt = job->uiop->uio_iovcnt;
        if (iovcnt > max_buf_aio)
                return (-1);
        for (i = 0; i < iovcnt; i++) {
                if (job->uiop->uio_iov[i].iov_len % vp->v_bufobj.bo_bsize != 0)
                        return (-1);
                if (job->uiop->uio_iov[i].iov_len > maxphys) {
                        error = -1;
                        return (-1);
                }
        }
        offset = cb->aio_offset;

        ref = 0;
        csw = devvn_refthread(vp, &dev, &ref);
        if (csw == NULL)
                return (ENXIO);

        if ((csw->d_flags & D_DISK) == 0) {
                error = -1;
                goto unref;
        }
        if (job->uiop->uio_resid > dev->si_iosize_max) {
                error = -1;
                goto unref;
        }

        ki = p->p_aioinfo;
        job->error = 0;

        use_unmapped = (dev->si_flags & SI_UNMAPPED) && unmapped_buf_allowed;
        if (!use_unmapped) {
                AIO_LOCK(ki);
                if (ki->kaio_buffer_count + iovcnt > max_buf_aio) {
                        AIO_UNLOCK(ki);
                        error = EAGAIN;
                        goto unref;
                }
                ki->kaio_buffer_count += iovcnt;
                AIO_UNLOCK(ki);
        }

        bios = malloc(sizeof(struct bio *) * iovcnt, M_TEMP, M_WAITOK);
        refcount_init(&job->nbio, iovcnt);
        for (i = 0; i < iovcnt; i++) {
                struct vm_page** pages;
                struct bio *bp;
                void *buf;
                size_t nbytes;
                int npages;

                buf = job->uiop->uio_iov[i].iov_base;
                nbytes = job->uiop->uio_iov[i].iov_len;

                bios[i] = g_alloc_bio();
                bp = bios[i];

                poff = (vm_offset_t)buf & PAGE_MASK;
                if (use_unmapped) {
                        pbuf = NULL;
                        pages = malloc(sizeof(vm_page_t) * (atop(round_page(
                            nbytes)) + 1), M_TEMP, M_WAITOK | M_ZERO);
                } else {
                        pbuf = uma_zalloc(pbuf_zone, M_WAITOK);
                        BUF_KERNPROC(pbuf);
                        pages = pbuf->b_pages;
                }

                bp->bio_length = nbytes;
                bp->bio_bcount = nbytes;
                bp->bio_done = aio_biowakeup;
                bp->bio_offset = offset;
                bp->bio_cmd = bio_cmd;
                bp->bio_dev = dev;
                bp->bio_caller1 = job;
                bp->bio_caller2 = pbuf;

                prot = VM_PROT_READ;
                if (opcode == LIO_READ || opcode == LIO_READV)
                        prot |= VM_PROT_WRITE;  /* Less backwards than it looks */
                npages = vm_fault_quick_hold_pages(&curproc->p_vmspace->vm_map,
                    (vm_offset_t)buf, bp->bio_length, prot, pages,
                    atop(maxphys) + 1);
                if (npages < 0) {
                        if (pbuf != NULL)
                                uma_zfree(pbuf_zone, pbuf);
                        else
                                free(pages, M_TEMP);
                        error = EFAULT;
                        g_destroy_bio(bp);
                        i--;
                        goto destroy_bios;
                }
                if (pbuf != NULL) {
                        pmap_qenter(pbuf->b_data, pages, npages);
                        bp->bio_data = pbuf->b_data + poff;
                        pbuf->b_npages = npages;
                        atomic_add_int(&num_buf_aio, 1);
                } else {
                        bp->bio_ma = pages;
                        bp->bio_ma_n = npages;
                        bp->bio_ma_offset = poff;
                        bp->bio_data = unmapped_buf;
                        bp->bio_flags |= BIO_UNMAPPED;
                        atomic_add_int(&num_unmapped_aio, 1);
                }

                offset += nbytes;
        }

        /* Perform transfer. */
        for (i = 0; i < iovcnt; i++)
                csw->d_strategy(bios[i]);
        free(bios, M_TEMP);

        dev_relthread(dev, ref);
        return (0);

destroy_bios:
        for (; i >= 0; i--)
                aio_biocleanup(bios[i]);
        free(bios, M_TEMP);
unref:
        dev_relthread(dev, ref);
        return (error);
}

#ifdef COMPAT_FREEBSD6
static int
convert_old_sigevent(struct osigevent *osig, struct sigevent *nsig)
{

        /*
         * Only SIGEV_NONE, SIGEV_SIGNAL, and SIGEV_KEVENT are
         * supported by AIO with the old sigevent structure.
         */
        nsig->sigev_notify = osig->sigev_notify;
        switch (nsig->sigev_notify) {
        case SIGEV_NONE:
                break;
        case SIGEV_SIGNAL:
                nsig->sigev_signo = osig->__sigev_u.__sigev_signo;
                break;
        case SIGEV_KEVENT:
                nsig->sigev_notify_kqueue =
                    osig->__sigev_u.__sigev_notify_kqueue;
                nsig->sigev_value.sival_ptr = osig->sigev_value.sival_ptr;
                break;
        default:
                return (EINVAL);
        }
        return (0);
}

static int
aiocb_copyin_old_sigevent(struct aiocb *ujob, struct kaiocb *kjob,
    int type __unused)
{
        struct oaiocb *ojob;
        struct aiocb *kcb = &kjob->uaiocb;
        int error;

        bzero(kcb, sizeof(struct aiocb));
        error = copyin(ujob, kcb, sizeof(struct oaiocb));
        if (error)
                return (error);
        /* No need to copyin aio_iov, because it did not exist in FreeBSD 6 */
        ojob = (struct oaiocb *)kcb;
        return (convert_old_sigevent(&ojob->aio_sigevent, &kcb->aio_sigevent));
}
#endif

static int
aiocb_copyin(struct aiocb *ujob, struct kaiocb *kjob, int type)
{
        struct aiocb *kcb = &kjob->uaiocb;
        int error;

        error = copyin(ujob, kcb, sizeof(struct aiocb));
        if (error)
                return (error);
        if (type == LIO_NOP)
                type = kcb->aio_lio_opcode;
        if (type & LIO_VECTORED) {
                /* malloc a uio and copy in the iovec */
                error = copyinuio(__DEVOLATILE(struct iovec*, kcb->aio_iov),
                    kcb->aio_iovcnt, &kjob->uiop);
        }

        return (error);
}

static long
aiocb_fetch_status(struct aiocb *ujob)
{

        return (fuword(&ujob->_aiocb_private.status));
}

static long
aiocb_fetch_error(struct aiocb *ujob)
{

        return (fuword(&ujob->_aiocb_private.error));
}

static int
aiocb_store_status(struct aiocb *ujob, long status)
{

        return (suword(&ujob->_aiocb_private.status, status));
}

static int
aiocb_store_error(struct aiocb *ujob, long error)
{

        return (suword(&ujob->_aiocb_private.error, error));
}

static int
aiocb_store_aiocb(struct aiocb **ujobp, struct aiocb *ujob)
{

        return (suword(ujobp, (long)ujob));
}

static struct aiocb_ops aiocb_ops = {
        .aio_copyin = aiocb_copyin,
        .fetch_status = aiocb_fetch_status,
        .fetch_error = aiocb_fetch_error,
        .store_status = aiocb_store_status,
        .store_error = aiocb_store_error,
        .store_aiocb = aiocb_store_aiocb,
};

#ifdef COMPAT_FREEBSD6
static struct aiocb_ops aiocb_ops_osigevent = {
        .aio_copyin = aiocb_copyin_old_sigevent,
        .fetch_status = aiocb_fetch_status,
        .fetch_error = aiocb_fetch_error,
        .store_status = aiocb_store_status,
        .store_error = aiocb_store_error,
        .store_aiocb = aiocb_store_aiocb,
};
#endif

/*
 * Queue a new AIO request.  Choosing either the threaded or direct bio VCHR
 * technique is done in this code.
 */
static int
aio_aqueue(struct thread *td, struct aiocb *ujob, struct aioliojob *lj,
    int type, struct aiocb_ops *ops)
{
        struct proc *p = td->td_proc;
        struct file *fp = NULL;
        struct kaiocb *job;
        struct kaioinfo *ki;
        struct kevent kev;
        int opcode;
        int error;
        int fd, kqfd;
        u_short evflags;

        if (p->p_aioinfo == NULL) {
                error = aio_init_aioinfo(p);
                if (error != 0)
                        goto err1;
        }

        ki = p->p_aioinfo;

        ops->store_status(ujob, -1);
        ops->store_error(ujob, 0);

        if (num_queue_count >= max_queue_count ||
            ki->kaio_count >= max_aio_queue_per_proc) {
                error = EAGAIN;
                goto err1;
        }

        job = uma_zalloc(aiocb_zone, M_WAITOK | M_ZERO);
        knlist_init_mtx(&job->klist, AIO_MTX(ki));

        error = ops->aio_copyin(ujob, job, type);
        if (error)
                goto err2;

        if (job->uaiocb.aio_nbytes > IOSIZE_MAX) {
                error = EINVAL;
                goto err2;
        }

        if (job->uaiocb.aio_sigevent.sigev_notify != SIGEV_KEVENT &&
            job->uaiocb.aio_sigevent.sigev_notify != SIGEV_SIGNAL &&
            job->uaiocb.aio_sigevent.sigev_notify != SIGEV_THREAD_ID &&
            job->uaiocb.aio_sigevent.sigev_notify != SIGEV_NONE) {
                error = EINVAL;
                goto err2;
        }

        if ((job->uaiocb.aio_sigevent.sigev_notify == SIGEV_SIGNAL ||
             job->uaiocb.aio_sigevent.sigev_notify == SIGEV_THREAD_ID) &&
                !_SIG_VALID(job->uaiocb.aio_sigevent.sigev_signo)) {
                error = EINVAL;
                goto err2;
        }

        /* Get the opcode. */
        if (type == LIO_NOP) {
                switch (job->uaiocb.aio_lio_opcode & ~LIO_FOFFSET) {
                case LIO_WRITE:
                case LIO_WRITEV:
                case LIO_NOP:
                case LIO_READ:
                case LIO_READV:
                        opcode = job->uaiocb.aio_lio_opcode & ~LIO_FOFFSET;
                        if ((job->uaiocb.aio_lio_opcode & LIO_FOFFSET) != 0)
                                job->ioflags |= KAIOCB_IO_FOFFSET;
                        break;
                default:
                        error = EINVAL;
                        goto err2;
                }
        } else
                opcode = job->uaiocb.aio_lio_opcode = type;

        ksiginfo_init(&job->ksi);

        /* Save userspace address of the job info. */
        job->ujob = ujob;

        /*
         * Validate the opcode and fetch the file object for the specified
         * file descriptor.
         *
         * XXXRW: Moved the opcode validation up here so that we don't
         * retrieve a file descriptor without knowing what the capabiltity
         * should be.
         */
        fd = job->uaiocb.aio_fildes;
        switch (opcode) {
        case LIO_WRITE:
        case LIO_WRITEV:
                error = fget_write(td, fd, &cap_pwrite_rights, &fp);
                break;
        case LIO_READ:
        case LIO_READV:
                error = fget_read(td, fd, &cap_pread_rights, &fp);
                break;
        case LIO_SYNC:
        case LIO_DSYNC:
                error = fget(td, fd, &cap_fsync_rights, &fp);
                break;
        case LIO_MLOCK:
                break;
        case LIO_NOP:
                error = fget(td, fd, &cap_no_rights, &fp);
                break;
        default:
                error = EINVAL;
        }
        if (error)
                goto err3;

        if ((opcode & LIO_SYNC) && fp->f_vnode == NULL) {
                error = EINVAL;
                goto err3;
        }

        if ((opcode == LIO_READ || opcode == LIO_READV ||
            opcode == LIO_WRITE || opcode == LIO_WRITEV) &&
            job->uaiocb.aio_offset < 0 &&
            (fp->f_vnode == NULL || fp->f_vnode->v_type != VCHR)) {
                error = EINVAL;
                goto err3;
        }

        if (fp != NULL && fp->f_ops == &path_fileops) {
                error = EBADF;
                goto err3;
        }

        job->fd_file = fp;

        mtx_lock(&aio_job_mtx);
        job->seqno = jobseqno++;
        mtx_unlock(&aio_job_mtx);
        if (opcode == LIO_NOP) {
                fdrop(fp, td);
                MPASS(job->uiop == &job->uio || job->uiop == NULL);
                uma_zfree(aiocb_zone, job);
                return (0);
        }

        if (job->uaiocb.aio_sigevent.sigev_notify != SIGEV_KEVENT)
                goto no_kqueue;
        evflags = job->uaiocb.aio_sigevent.sigev_notify_kevent_flags;
        if ((evflags & ~(EV_CLEAR | EV_DISPATCH | EV_ONESHOT)) != 0) {
                error = EINVAL;
                goto err3;
        }
        kqfd = job->uaiocb.aio_sigevent.sigev_notify_kqueue;
        memset(&kev, 0, sizeof(kev));
        kev.ident = (uintptr_t)job->ujob;
        kev.filter = EVFILT_AIO;
        kev.flags = EV_ADD | EV_ENABLE | EV_FLAG1 | evflags;
        kev.data = (intptr_t)job;
        kev.udata = job->uaiocb.aio_sigevent.sigev_value.sival_ptr;
        error = kqfd_register(kqfd, &kev, td, M_WAITOK);
        if (error)
                goto err3;

no_kqueue:

        ops->store_error(ujob, EINPROGRESS);
        job->uaiocb._aiocb_private.error = EINPROGRESS;
        job->userproc = p;
        job->cred = crhold(td->td_ucred);
        job->jobflags = KAIOCB_QUEUEING;
        job->lio = lj;

        if (opcode & LIO_VECTORED) {
                /* Use the uio copied in by aio_copyin */
                MPASS(job->uiop != &job->uio && job->uiop != NULL);
        } else {
                /* Setup the inline uio */
                job->iov[0].iov_base = (void *)(uintptr_t)job->uaiocb.aio_buf;
                job->iov[0].iov_len = job->uaiocb.aio_nbytes;
                job->uio.uio_iov = job->iov;
                job->uio.uio_iovcnt = 1;
                job->uio.uio_resid = job->uaiocb.aio_nbytes;
                job->uio.uio_segflg = UIO_USERSPACE;
                job->uiop = &job->uio;
        }
        switch (opcode & (LIO_READ | LIO_WRITE)) {
        case LIO_READ:
                job->uiop->uio_rw = UIO_READ;
                break;
        case LIO_WRITE:
                job->uiop->uio_rw = UIO_WRITE;
                break;
        }
        job->uiop->uio_offset = job->uaiocb.aio_offset;
        job->uiop->uio_td = td;

        if (opcode == LIO_MLOCK) {
                aio_schedule(job, aio_process_mlock);
                error = 0;
        } else if (fp->f_ops->fo_aio_queue == NULL)
                error = aio_queue_file(fp, job);
        else
                error = fo_aio_queue(fp, job);
        if (error)
                goto err4;

        AIO_LOCK(ki);
        job->jobflags &= ~KAIOCB_QUEUEING;
        TAILQ_INSERT_TAIL(&ki->kaio_all, job, allist);
        ki->kaio_count++;
        if (lj)
                lj->lioj_count++;
        atomic_add_int(&num_queue_count, 1);
        if (job->jobflags & KAIOCB_FINISHED) {
                /*
                 * The queue callback completed the request synchronously.
                 * The bulk of the completion is deferred in that case
                 * until this point.
                 */
                aio_bio_done_notify(p, job);
        } else
                TAILQ_INSERT_TAIL(&ki->kaio_jobqueue, job, plist);
        AIO_UNLOCK(ki);
        return (0);

err4:
        crfree(job->cred);
err3:
        if (fp)
                fdrop(fp, td);
        knlist_delete(&job->klist, curthread, 0);
err2:
        if (job->uiop != &job->uio)
                freeuio(job->uiop);
        uma_zfree(aiocb_zone, job);
err1:
        ops->store_error(ujob, error);
        return (error);
}

static void
aio_cancel_daemon_job(struct kaiocb *job)
{

        mtx_lock(&aio_job_mtx);
        if (!aio_cancel_cleared(job))
                TAILQ_REMOVE(&aio_jobs, job, list);
        mtx_unlock(&aio_job_mtx);
        aio_cancel(job);
}

void
aio_schedule(struct kaiocb *job, aio_handle_fn_t *func)
{

        mtx_lock(&aio_job_mtx);
        if (!aio_set_cancel_function(job, aio_cancel_daemon_job)) {
                mtx_unlock(&aio_job_mtx);
                aio_cancel(job);
                return;
        }
        job->handle_fn = func;
        TAILQ_INSERT_TAIL(&aio_jobs, job, list);
        aio_kick_nowait(job->userproc);
        mtx_unlock(&aio_job_mtx);
}

static void
aio_cancel_sync(struct kaiocb *job)
{
        struct kaioinfo *ki;

        ki = job->userproc->p_aioinfo;
        AIO_LOCK(ki);
        if (!aio_cancel_cleared(job))
                TAILQ_REMOVE(&ki->kaio_syncqueue, job, list);
        AIO_UNLOCK(ki);
        aio_cancel(job);
}

int
aio_queue_file(struct file *fp, struct kaiocb *job)
{
        struct kaioinfo *ki;
        struct kaiocb *job2;
        struct vnode *vp;
        struct mount *mp;
        int error;
        bool safe;

        ki = job->userproc->p_aioinfo;
        error = aio_qbio(job->userproc, job);
        if (error >= 0)
                return (error);
        safe = false;
        if (fp->f_type == DTYPE_VNODE) {
                vp = fp->f_vnode;
                if (vp->v_type == VREG || vp->v_type == VDIR) {
                        mp = fp->f_vnode->v_mount;
                        if (mp == NULL || (mp->mnt_flag & MNT_LOCAL) != 0)
                                safe = true;
                }
        }
        if (!(safe || enable_aio_unsafe)) {
                counted_warning(&unsafe_warningcnt,
                    "is attempting to use unsafe AIO requests");
                return (EOPNOTSUPP);
        }

        if (job->uaiocb.aio_lio_opcode & (LIO_WRITE | LIO_READ)) {
                aio_schedule(job, aio_process_rw);
                error = 0;
        } else if (job->uaiocb.aio_lio_opcode & LIO_SYNC) {
                AIO_LOCK(ki);
                TAILQ_FOREACH(job2, &ki->kaio_jobqueue, plist) {
                        if ((job2->jobflags & KAIOCB_MARKER) != 0)
                                continue;
                        if (job2->fd_file == job->fd_file &&
                            ((job2->uaiocb.aio_lio_opcode & LIO_SYNC) == 0) &&
                            job2->seqno < job->seqno) {
                                job2->jobflags |= KAIOCB_CHECKSYNC;
                                job->pending++;
                        }
                }
                if (job->pending != 0) {
                        if (!aio_set_cancel_function_locked(job,
                                aio_cancel_sync)) {
                                AIO_UNLOCK(ki);
                                aio_cancel(job);
                                return (0);
                        }
                        TAILQ_INSERT_TAIL(&ki->kaio_syncqueue, job, list);
                        AIO_UNLOCK(ki);
                        return (0);
                }
                AIO_UNLOCK(ki);
                aio_schedule(job, aio_process_sync);
                error = 0;
        } else {
                error = EINVAL;
        }
        return (error);
}

static void
aio_kick_nowait(struct proc *userp)
{
        struct kaioinfo *ki = userp->p_aioinfo;
        struct aioproc *aiop;

        mtx_assert(&aio_job_mtx, MA_OWNED);
        if ((aiop = TAILQ_FIRST(&aio_freeproc)) != NULL) {
                TAILQ_REMOVE(&aio_freeproc, aiop, list);
                aiop->aioprocflags &= ~AIOP_FREE;
                wakeup(aiop->aioproc);
        } else if (num_aio_resv_start + num_aio_procs < max_aio_procs &&
            ki->kaio_active_count + num_aio_resv_start < max_aio_per_proc) {
                taskqueue_enqueue(taskqueue_aiod_kick, &ki->kaio_task);
        }
}

static int
aio_kick(struct proc *userp)
{
        struct kaioinfo *ki = userp->p_aioinfo;
        struct aioproc *aiop;
        int error, ret = 0;

        mtx_assert(&aio_job_mtx, MA_OWNED);
retryproc:
        if ((aiop = TAILQ_FIRST(&aio_freeproc)) != NULL) {
                TAILQ_REMOVE(&aio_freeproc, aiop, list);
                aiop->aioprocflags &= ~AIOP_FREE;
                wakeup(aiop->aioproc);
        } else if (num_aio_resv_start + num_aio_procs < max_aio_procs &&
            ki->kaio_active_count + num_aio_resv_start < max_aio_per_proc) {
                num_aio_resv_start++;
                mtx_unlock(&aio_job_mtx);
                error = aio_newproc(&num_aio_resv_start);
                mtx_lock(&aio_job_mtx);
                if (error) {
                        num_aio_resv_start--;
                        goto retryproc;
                }
        } else {
                ret = -1;
        }
        return (ret);
}

static void
aio_kick_helper(void *context, int pending)
{
        struct proc *userp = context;

        mtx_lock(&aio_job_mtx);
        while (--pending >= 0) {
                if (aio_kick(userp))
                        break;
        }
        mtx_unlock(&aio_job_mtx);
}

/*
 * Support the aio_return system call, as a side-effect, kernel resources are
 * released.
 */
static int
kern_aio_return(struct thread *td, struct aiocb *ujob, struct aiocb_ops *ops)
{
        struct proc *p = td->td_proc;
        struct kaiocb *job;
        struct kaioinfo *ki;
        long status, error;

        ki = p->p_aioinfo;
        if (ki == NULL)
                return (EINVAL);
        AIO_LOCK(ki);
        TAILQ_FOREACH(job, &ki->kaio_done, plist) {
                if (job->ujob == ujob)
                        break;
        }
        if (job != NULL) {
                MPASS(job->jobflags & KAIOCB_FINISHED);
                status = job->uaiocb._aiocb_private.status;
                error = job->uaiocb._aiocb_private.error;
                td->td_retval[0] = status;
                td->td_ru.ru_oublock += job->outblock;
                td->td_ru.ru_inblock += job->inblock;
                td->td_ru.ru_msgsnd += job->msgsnd;
                td->td_ru.ru_msgrcv += job->msgrcv;
                aio_free_entry(job);
                AIO_UNLOCK(ki);
                ops->store_error(ujob, error);
                ops->store_status(ujob, status);
        } else {
                error = EINVAL;
                AIO_UNLOCK(ki);
        }
        return (error);
}

int
sys_aio_return(struct thread *td, struct aio_return_args *uap)
{

        return (kern_aio_return(td, uap->aiocbp, &aiocb_ops));
}

/*
 * Allow a process to wakeup when any of the I/O requests are completed.
 */
static int
kern_aio_suspend(struct thread *td, int njoblist, struct aiocb **ujoblist,
    struct timespec *ts)
{
        struct proc *p = td->td_proc;
        struct timeval atv;
        struct kaioinfo *ki;
        struct kaiocb *firstjob, *job;
        int error, i, timo;

        timo = 0;
        if (ts) {
                if (ts->tv_nsec < 0 || ts->tv_nsec >= 1000000000)
                        return (EINVAL);

                TIMESPEC_TO_TIMEVAL(&atv, ts);
                if (itimerfix(&atv))
                        return (EINVAL);
                timo = tvtohz(&atv);
        }

        ki = p->p_aioinfo;
        if (ki == NULL)
                return (EAGAIN);

        if (njoblist == 0)
                return (0);

        AIO_LOCK(ki);
        for (;;) {
                firstjob = NULL;
                error = 0;
                TAILQ_FOREACH(job, &ki->kaio_all, allist) {
                        for (i = 0; i < njoblist; i++) {
                                if (job->ujob == ujoblist[i]) {
                                        if (firstjob == NULL)
                                                firstjob = job;
                                        if (job->jobflags & KAIOCB_FINISHED)
                                                goto RETURN;
                                }
                        }
                }
                /* All tasks were finished. */
                if (firstjob == NULL)
                        break;

                ki->kaio_flags |= KAIO_WAKEUP;
                error = msleep(&p->p_aioinfo, AIO_MTX(ki), PRIBIO | PCATCH,
                    "aiospn", timo);
                if (error == ERESTART)
                        error = EINTR;
                if (error)
                        break;
        }
RETURN:
        AIO_UNLOCK(ki);
        return (error);
}

int
sys_aio_suspend(struct thread *td, struct aio_suspend_args *uap)
{
        struct timespec ts, *tsp;
        struct aiocb **ujoblist;
        int error;

        if (uap->nent < 0 || uap->nent > max_aio_queue_per_proc)
                return (EINVAL);

        if (uap->timeout) {
                /* Get timespec struct. */
                if ((error = copyin(uap->timeout, &ts, sizeof(ts))) != 0)
                        return (error);
                tsp = &ts;
        } else
                tsp = NULL;

        ujoblist = malloc(uap->nent * sizeof(ujoblist[0]), M_AIO, M_WAITOK);
        error = copyin(uap->aiocbp, ujoblist, uap->nent * sizeof(ujoblist[0]));
        if (error == 0)
                error = kern_aio_suspend(td, uap->nent, ujoblist, tsp);
        free(ujoblist, M_AIO);
        return (error);
}

/*
 * aio_cancel cancels any non-bio aio operations not currently in progress.
 */
int
sys_aio_cancel(struct thread *td, struct aio_cancel_args *uap)
{
        struct proc *p = td->td_proc;
        struct kaioinfo *ki;
        struct kaiocb *job, *jobn, marker;
        struct file *fp;
        int error;
        int cancelled = 0;
        int notcancelled = 0;
        struct vnode *vp;

        /* Lookup file object. */
        error = fget(td, uap->fd, &cap_no_rights, &fp);
        if (error)
                return (error);

        ki = p->p_aioinfo;
        if (ki == NULL)
                goto done;

        if (fp->f_type == DTYPE_VNODE) {
                vp = fp->f_vnode;
                if (vn_isdisk(vp)) {
                        fdrop(fp, td);
                        td->td_retval[0] = AIO_NOTCANCELED;
                        return (0);
                }
        }

        /*
         * We may have to drop the list mutex in order to cancel a job.  After
         * that point it is unsafe to rely on the stability of the list.  We
         * could restart the search from the beginning after canceling a job,
         * but this may inefficient.  Instead, use a marker job to keep our
         * place in the list.
         */
        memset(&marker, 0, sizeof(marker));
        marker.jobflags = KAIOCB_MARKER;

        AIO_LOCK(ki);
        TAILQ_FOREACH_SAFE(job, &ki->kaio_jobqueue, plist, jobn) {
                if (uap->fd == job->uaiocb.aio_fildes &&
                    (uap->aiocbp == NULL || uap->aiocbp == job->ujob) &&
                    (job->jobflags & KAIOCB_MARKER) == 0) {
                        TAILQ_INSERT_AFTER(&ki->kaio_jobqueue, job, &marker,
                            plist);
                        if (aio_cancel_job(p, ki, job)) {
                                cancelled++;
                        } else {
                                notcancelled++;
                        }
                        jobn = TAILQ_NEXT(&marker, plist);
                        TAILQ_REMOVE(&ki->kaio_jobqueue, &marker, plist);
                        if (uap->aiocbp != NULL)
                                break;
                }
        }
        AIO_UNLOCK(ki);

done:
        fdrop(fp, td);

        if (uap->aiocbp != NULL) {
                if (cancelled) {
                        td->td_retval[0] = AIO_CANCELED;
                        return (0);
                }
        }

        if (notcancelled) {
                td->td_retval[0] = AIO_NOTCANCELED;
                return (0);
        }

        if (cancelled) {
                td->td_retval[0] = AIO_CANCELED;
                return (0);
        }

        td->td_retval[0] = AIO_ALLDONE;

        return (0);
}

/*
 * aio_error is implemented in the kernel level for compatibility purposes
 * only.  For a user mode async implementation, it would be best to do it in
 * a userland subroutine.
 */
static int
kern_aio_error(struct thread *td, struct aiocb *ujob, struct aiocb_ops *ops)
{
        struct proc *p = td->td_proc;
        struct kaiocb *job;
        struct kaioinfo *ki;
        int status;

        ki = p->p_aioinfo;
        if (ki == NULL) {
                td->td_retval[0] = EINVAL;
                return (0);
        }

        AIO_LOCK(ki);
        TAILQ_FOREACH(job, &ki->kaio_all, allist) {
                if (job->ujob == ujob) {
                        if (job->jobflags & KAIOCB_FINISHED)
                                td->td_retval[0] =
                                        job->uaiocb._aiocb_private.error;
                        else
                                td->td_retval[0] = EINPROGRESS;
                        AIO_UNLOCK(ki);
                        return (0);
                }
        }
        AIO_UNLOCK(ki);

        /*
         * Hack for failure of aio_aqueue.
         */
        status = ops->fetch_status(ujob);
        if (status == -1) {
                td->td_retval[0] = ops->fetch_error(ujob);
                return (0);
        }

        td->td_retval[0] = EINVAL;
        return (0);
}

int
sys_aio_error(struct thread *td, struct aio_error_args *uap)
{

        return (kern_aio_error(td, uap->aiocbp, &aiocb_ops));
}

/* syscall - asynchronous read from a file (REALTIME) */
#ifdef COMPAT_FREEBSD6
int
freebsd6_aio_read(struct thread *td, struct freebsd6_aio_read_args *uap)
{

        return (aio_aqueue(td, (struct aiocb *)uap->aiocbp, NULL, LIO_READ,
            &aiocb_ops_osigevent));
}
#endif

int
sys_aio_read(struct thread *td, struct aio_read_args *uap)
{

        return (aio_aqueue(td, uap->aiocbp, NULL, LIO_READ, &aiocb_ops));
}

int
sys_aio_readv(struct thread *td, struct aio_readv_args *uap)
{

        return (aio_aqueue(td, uap->aiocbp, NULL, LIO_READV, &aiocb_ops));
}

/* syscall - asynchronous write to a file (REALTIME) */
#ifdef COMPAT_FREEBSD6
int
freebsd6_aio_write(struct thread *td, struct freebsd6_aio_write_args *uap)
{

        return (aio_aqueue(td, (struct aiocb *)uap->aiocbp, NULL, LIO_WRITE,
            &aiocb_ops_osigevent));
}
#endif

int
sys_aio_write(struct thread *td, struct aio_write_args *uap)
{

        return (aio_aqueue(td, uap->aiocbp, NULL, LIO_WRITE, &aiocb_ops));
}

int
sys_aio_writev(struct thread *td, struct aio_writev_args *uap)
{

        return (aio_aqueue(td, uap->aiocbp, NULL, LIO_WRITEV, &aiocb_ops));
}

int
sys_aio_mlock(struct thread *td, struct aio_mlock_args *uap)
{

        return (aio_aqueue(td, uap->aiocbp, NULL, LIO_MLOCK, &aiocb_ops));
}

static int
kern_lio_listio(struct thread *td, int mode, struct aiocb * const *uacb_list,
    struct aiocb **acb_list, int nent, struct sigevent *sig,
    struct aiocb_ops *ops)
{
        struct proc *p = td->td_proc;
        struct aiocb *job;
        struct kaioinfo *ki;
        struct aioliojob *lj;
        struct kevent kev;
        int error;
        int nagain, nerror;
        int i;

        if ((mode != LIO_NOWAIT) && (mode != LIO_WAIT))
                return (EINVAL);

        if (nent < 0 || nent > max_aio_queue_per_proc)
                return (EINVAL);

        if (p->p_aioinfo == NULL) {
                error = aio_init_aioinfo(p);
                if (error != 0)
                        return (error);
        }

        ki = p->p_aioinfo;

        lj = uma_zalloc(aiolio_zone, M_WAITOK);
        lj->lioj_flags = 0;
        lj->lioj_count = 0;
        lj->lioj_finished_count = 0;
        lj->lioj_signal.sigev_notify = SIGEV_NONE;
        knlist_init_mtx(&lj->klist, AIO_MTX(ki));
        ksiginfo_init(&lj->lioj_ksi);

        /*
         * Setup signal.
         */
        if (sig && (mode == LIO_NOWAIT)) {
                bcopy(sig, &lj->lioj_signal, sizeof(lj->lioj_signal));
                if (lj->lioj_signal.sigev_notify == SIGEV_KEVENT) {
                        /* Assume only new style KEVENT */
                        memset(&kev, 0, sizeof(kev));
                        kev.filter = EVFILT_LIO;
                        kev.flags = EV_ADD | EV_ENABLE | EV_FLAG1;
                        kev.ident = (uintptr_t)uacb_list; /* something unique */
                        kev.data = (intptr_t)lj;
                        /* pass user defined sigval data */
                        kev.udata = lj->lioj_signal.sigev_value.sival_ptr;
                        error = kqfd_register(
                            lj->lioj_signal.sigev_notify_kqueue, &kev, td,
                            M_WAITOK);
                        if (error) {
                                uma_zfree(aiolio_zone, lj);
                                return (error);
                        }
                } else if (lj->lioj_signal.sigev_notify == SIGEV_NONE) {
                        ;
                } else if (lj->lioj_signal.sigev_notify == SIGEV_SIGNAL ||
                           lj->lioj_signal.sigev_notify == SIGEV_THREAD_ID) {
                                if (!_SIG_VALID(lj->lioj_signal.sigev_signo)) {
                                        uma_zfree(aiolio_zone, lj);
                                        return EINVAL;
                                }
                                lj->lioj_flags |= LIOJ_SIGNAL;
                } else {
                        uma_zfree(aiolio_zone, lj);
                        return EINVAL;
                }
        }

        AIO_LOCK(ki);
        TAILQ_INSERT_TAIL(&ki->kaio_liojoblist, lj, lioj_list);
        /*
         * Add extra aiocb count to avoid the lio to be freed
         * by other threads doing aio_waitcomplete or aio_return,
         * and prevent event from being sent until we have queued
         * all tasks.
         */
        lj->lioj_count = 1;
        AIO_UNLOCK(ki);

        /*
         * Get pointers to the list of I/O requests.
         */
        nagain = 0;
        nerror = 0;
        for (i = 0; i < nent; i++) {
                job = acb_list[i];
                if (job != NULL) {
                        error = aio_aqueue(td, job, lj, LIO_NOP, ops);
                        if (error == EAGAIN)
                                nagain++;
                        else if (error != 0)
                                nerror++;
                }
        }

        error = 0;
        AIO_LOCK(ki);
        if (mode == LIO_WAIT) {
                while (lj->lioj_count - 1 != lj->lioj_finished_count) {
                        ki->kaio_flags |= KAIO_WAKEUP;
                        error = msleep(&p->p_aioinfo, AIO_MTX(ki),
                            PRIBIO | PCATCH, "aiospn", 0);
                        if (error == ERESTART)
                                error = EINTR;
                        if (error)
                                break;
                }
        } else {
                if (lj->lioj_count - 1 == lj->lioj_finished_count) {
                        if (lj->lioj_signal.sigev_notify == SIGEV_KEVENT) {
                                lj->lioj_flags |= LIOJ_KEVENT_POSTED;
                                KNOTE_LOCKED(&lj->klist, 1);
                        }
                        if ((lj->lioj_flags & (LIOJ_SIGNAL |
                            LIOJ_SIGNAL_POSTED)) == LIOJ_SIGNAL &&
                            (lj->lioj_signal.sigev_notify == SIGEV_SIGNAL ||
                            lj->lioj_signal.sigev_notify == SIGEV_THREAD_ID)) {
                                aio_sendsig(p, &lj->lioj_signal, &lj->lioj_ksi,
                                    lj->lioj_count != 1);
                                lj->lioj_flags |= LIOJ_SIGNAL_POSTED;
                        }
                }
        }
        lj->lioj_count--;
        if (lj->lioj_count == 0) {
                TAILQ_REMOVE(&ki->kaio_liojoblist, lj, lioj_list);
                knlist_delete(&lj->klist, curthread, 1);
                PROC_LOCK(p);
                sigqueue_take(&lj->lioj_ksi);
                PROC_UNLOCK(p);
                AIO_UNLOCK(ki);
                uma_zfree(aiolio_zone, lj);
        } else
                AIO_UNLOCK(ki);

        if (nerror)
                return (EIO);
        else if (nagain)
                return (EAGAIN);
        else
                return (error);
}

/* syscall - list directed I/O (REALTIME) */
#ifdef COMPAT_FREEBSD6
int
freebsd6_lio_listio(struct thread *td, struct freebsd6_lio_listio_args *uap)
{
        struct aiocb **acb_list;
        struct sigevent *sigp, sig;
        struct osigevent osig;
        int error, nent;

        if ((uap->mode != LIO_NOWAIT) && (uap->mode != LIO_WAIT))
                return (EINVAL);

        nent = uap->nent;
        if (nent < 0 || nent > max_aio_queue_per_proc)
                return (EINVAL);

        if (uap->sig && (uap->mode == LIO_NOWAIT)) {
                error = copyin(uap->sig, &osig, sizeof(osig));
                if (error)
                        return (error);
                error = convert_old_sigevent(&osig, &sig);
                if (error)
                        return (error);
                sigp = &sig;
        } else
                sigp = NULL;

        acb_list = malloc(sizeof(struct aiocb *) * nent, M_LIO, M_WAITOK);
        error = copyin(uap->acb_list, acb_list, nent * sizeof(acb_list[0]));
        if (error == 0)
                error = kern_lio_listio(td, uap->mode,
                    (struct aiocb * const *)uap->acb_list, acb_list, nent, sigp,
                    &aiocb_ops_osigevent);
        free(acb_list, M_LIO);
        return (error);
}
#endif

/* syscall - list directed I/O (REALTIME) */
int
sys_lio_listio(struct thread *td, struct lio_listio_args *uap)
{
        struct aiocb **acb_list;
        struct sigevent *sigp, sig;
        int error, nent;

        if ((uap->mode != LIO_NOWAIT) && (uap->mode != LIO_WAIT))
                return (EINVAL);

        nent = uap->nent;
        if (nent < 0 || nent > max_aio_queue_per_proc)
                return (EINVAL);

        if (uap->sig && (uap->mode == LIO_NOWAIT)) {
                error = copyin(uap->sig, &sig, sizeof(sig));
                if (error)
                        return (error);
                sigp = &sig;
        } else
                sigp = NULL;

        acb_list = malloc(sizeof(struct aiocb *) * nent, M_LIO, M_WAITOK);
        error = copyin(uap->acb_list, acb_list, nent * sizeof(acb_list[0]));
        if (error == 0)
                error = kern_lio_listio(td, uap->mode, uap->acb_list, acb_list,
                    nent, sigp, &aiocb_ops);
        free(acb_list, M_LIO);
        return (error);
}

static void
aio_biocleanup(struct bio *bp)
{
        struct kaiocb *job = (struct kaiocb *)bp->bio_caller1;
        struct kaioinfo *ki;
        struct buf *pbuf = (struct buf *)bp->bio_caller2;

        /* Release mapping into kernel space. */
        if (pbuf != NULL) {
                MPASS(pbuf->b_npages <= atop(maxphys) + 1);
                pmap_qremove(pbuf->b_data, pbuf->b_npages);
                vm_page_unhold_pages(pbuf->b_pages, pbuf->b_npages);
                uma_zfree(pbuf_zone, pbuf);
                atomic_subtract_int(&num_buf_aio, 1);
                ki = job->userproc->p_aioinfo;
                AIO_LOCK(ki);
                ki->kaio_buffer_count--;
                AIO_UNLOCK(ki);
        } else {
                MPASS(bp->bio_ma_n <= atop(maxphys) + 1);
                vm_page_unhold_pages(bp->bio_ma, bp->bio_ma_n);
                free(bp->bio_ma, M_TEMP);
                atomic_subtract_int(&num_unmapped_aio, 1);
        }
        g_destroy_bio(bp);
}

static void
aio_biowakeup(struct bio *bp)
{
        struct kaiocb *job = (struct kaiocb *)bp->bio_caller1;
        size_t nbytes;
        long bcount = bp->bio_bcount;
        long resid = bp->bio_resid;
        int opcode, nblks;
        int abio_error = bp->bio_error;
        uint16_t flags = bp->bio_flags;

        opcode = job->uaiocb.aio_lio_opcode;

        aio_biocleanup(bp);

        nbytes = bcount - resid;
        atomic_add_acq_long(&job->nbytes, nbytes);
        nblks = btodb(nbytes);

        /*
         * If multiple bios experienced an error, the job will reflect the
         * error of whichever failed bio completed last.
         */
        if (flags & BIO_ERROR)
                atomic_store_int(&job->error, abio_error);
        if (opcode & LIO_WRITE)
                atomic_add_int(&job->outblock, nblks);
        else
                atomic_add_int(&job->inblock, nblks);

        if (refcount_release(&job->nbio)) {
                abio_error = atomic_load_int(&job->error);
                if (abio_error != 0)
                        aio_complete(job, -1, abio_error);
                else
                        aio_complete(job, atomic_load_long(&job->nbytes), 0);
        }
}

/* syscall - wait for the next completion of an aio request */
static int
kern_aio_waitcomplete(struct thread *td, struct aiocb **ujobp,
    struct timespec *ts, struct aiocb_ops *ops)
{
        struct proc *p = td->td_proc;
        struct timeval atv;
        struct kaioinfo *ki;
        struct kaiocb *job;
        struct aiocb *ujob;
        long error, status;
        int timo;

        ops->store_aiocb(ujobp, NULL);

        if (ts == NULL) {
                timo = 0;
        } else if (ts->tv_sec == 0 && ts->tv_nsec == 0) {
                timo = -1;
        } else {
                if ((ts->tv_nsec < 0) || (ts->tv_nsec >= 1000000000))
                        return (EINVAL);

                TIMESPEC_TO_TIMEVAL(&atv, ts);
                if (itimerfix(&atv))
                        return (EINVAL);
                timo = tvtohz(&atv);
        }

        if (p->p_aioinfo == NULL) {
                error = aio_init_aioinfo(p);
                if (error != 0)
                        return (error);
        }
        ki = p->p_aioinfo;

        error = 0;
        job = NULL;
        AIO_LOCK(ki);
        while ((job = TAILQ_FIRST(&ki->kaio_done)) == NULL) {
                if (timo == -1) {
                        error = EWOULDBLOCK;
                        break;
                }
                ki->kaio_flags |= KAIO_WAKEUP;
                error = msleep(&p->p_aioinfo, AIO_MTX(ki), PRIBIO | PCATCH,
                    "aiowc", timo);
                if (timo && error == ERESTART)
                        error = EINTR;
                if (error)
                        break;
        }

        if (job != NULL) {
                MPASS(job->jobflags & KAIOCB_FINISHED);
                ujob = job->ujob;
                status = job->uaiocb._aiocb_private.status;
                error = job->uaiocb._aiocb_private.error;
                td->td_retval[0] = status;
                td->td_ru.ru_oublock += job->outblock;
                td->td_ru.ru_inblock += job->inblock;
                td->td_ru.ru_msgsnd += job->msgsnd;
                td->td_ru.ru_msgrcv += job->msgrcv;
                aio_free_entry(job);
                AIO_UNLOCK(ki);
                ops->store_aiocb(ujobp, ujob);
                ops->store_error(ujob, error);
                ops->store_status(ujob, status);
        } else
                AIO_UNLOCK(ki);

        return (error);
}

int
sys_aio_waitcomplete(struct thread *td, struct aio_waitcomplete_args *uap)
{
        struct timespec ts, *tsp;
        int error;

        if (uap->timeout) {
                /* Get timespec struct. */
                error = copyin(uap->timeout, &ts, sizeof(ts));
                if (error)
                        return (error);
                tsp = &ts;
        } else
                tsp = NULL;

        return (kern_aio_waitcomplete(td, uap->aiocbp, tsp, &aiocb_ops));
}

static int
kern_aio_fsync(struct thread *td, int op, struct aiocb *ujob,
    struct aiocb_ops *ops)
{
        int listop;

        switch (op) {
        case O_SYNC:
                listop = LIO_SYNC;
                break;
        case O_DSYNC:
                listop = LIO_DSYNC;
                break;
        default:
                return (EINVAL);
        }

        return (aio_aqueue(td, ujob, NULL, listop, ops));
}

int
sys_aio_fsync(struct thread *td, struct aio_fsync_args *uap)
{

        return (kern_aio_fsync(td, uap->op, uap->aiocbp, &aiocb_ops));
}

/* kqueue attach function */
static int
filt_aioattach(struct knote *kn)
{
        struct kaiocb *job;

        job = (struct kaiocb *)(uintptr_t)kn->kn_sdata;

        /*
         * The job pointer must be validated before using it, so
         * registration is restricted to the kernel; the user cannot
         * set EV_FLAG1.
         */
        if ((kn->kn_flags & EV_FLAG1) == 0)
                return (EPERM);
        kn->kn_ptr.p_aio = job;
        kn->kn_flags &= ~EV_FLAG1;

        knlist_add(&job->klist, kn, 0);

        return (0);
}

/* kqueue detach function */
static void
filt_aiodetach(struct knote *kn)
{
        struct knlist *knl;

        knl = &kn->kn_ptr.p_aio->klist;
        knl->kl_lock(knl->kl_lockarg);
        knlist_remove(knl, kn, 1);
        knl->kl_unlock(knl->kl_lockarg);
}

/* kqueue filter function */
/*ARGSUSED*/
static int
filt_aio(struct knote *kn, long hint)
{
        struct kaiocb *job = kn->kn_ptr.p_aio;

        kn->kn_data = job->uaiocb._aiocb_private.error;
        if (!(job->jobflags & KAIOCB_FINISHED))
                return (0);
        kn->kn_flags |= EV_EOF;
        return (1);
}

/* kqueue attach function */
static int
filt_lioattach(struct knote *kn)
{
        struct aioliojob *lj;

        lj = (struct aioliojob *)(uintptr_t)kn->kn_sdata;

        /*
         * The aioliojob pointer must be validated before using it, so
         * registration is restricted to the kernel; the user cannot
         * set EV_FLAG1.
         */
        if ((kn->kn_flags & EV_FLAG1) == 0)
                return (EPERM);
        kn->kn_ptr.p_lio = lj;
        kn->kn_flags &= ~EV_FLAG1;

        knlist_add(&lj->klist, kn, 0);

        return (0);
}

/* kqueue detach function */
static void
filt_liodetach(struct knote *kn)
{
        struct knlist *knl;

        knl = &kn->kn_ptr.p_lio->klist;
        knl->kl_lock(knl->kl_lockarg);
        knlist_remove(knl, kn, 1);
        knl->kl_unlock(knl->kl_lockarg);
}

/* kqueue filter function */
/*ARGSUSED*/
static int
filt_lio(struct knote *kn, long hint)
{
        struct aioliojob * lj = kn->kn_ptr.p_lio;

        return (lj->lioj_flags & LIOJ_KEVENT_POSTED);
}

#ifdef COMPAT_FREEBSD32
#include <sys/mount.h>
#include <sys/socket.h>
#include <sys/sysent.h>
#include <compat/freebsd32/freebsd32.h>
#include <compat/freebsd32/freebsd32_proto.h>
#include <compat/freebsd32/freebsd32_signal.h>
#include <compat/freebsd32/freebsd32_syscall.h>
#include <compat/freebsd32/freebsd32_util.h>

struct __aiocb_private32 {
        int32_t status;
        int32_t error;
        uint32_t spare;
};

#ifdef COMPAT_FREEBSD6
typedef struct oaiocb32 {
        int     aio_fildes;             /* File descriptor */
#ifdef __amd64__
        uint64_t aio_offset __packed;   /* File offset for I/O */
#else
        uint64_t aio_offset;            /* File offset for I/O */
#endif
        uint32_t aio_buf;               /* I/O buffer in process space */
        uint32_t aio_nbytes;            /* Number of bytes for I/O */
        struct  osigevent32 aio_sigevent; /* Signal to deliver */
        int     aio_lio_opcode;         /* LIO opcode */
        int     aio_reqprio;            /* Request priority -- ignored */
        struct  __aiocb_private32 _aiocb_private;
} oaiocb32_t;
#endif

typedef struct aiocb32 {
        int32_t aio_fildes;             /* File descriptor */
#ifdef __amd64__
        uint64_t aio_offset __packed;   /* File offset for I/O */
#else
        uint64_t aio_offset;            /* File offset for I/O*/
#endif
        uint32_t aio_buf;       /* I/O buffer in process space */
        uint32_t aio_nbytes;    /* Number of bytes for I/O */
        int     __spare__[2];
        uint32_t __spare2__;
        int     aio_lio_opcode;         /* LIO opcode */
        int     aio_reqprio;            /* Request priority -- ignored */
        struct  __aiocb_private32 _aiocb_private;
        struct  sigevent32 aio_sigevent;        /* Signal to deliver */
} aiocb32_t;

#ifdef COMPAT_FREEBSD6
static int
convert_old_sigevent32(struct osigevent32 *osig, struct sigevent *nsig)
{

        /*
         * Only SIGEV_NONE, SIGEV_SIGNAL, and SIGEV_KEVENT are
         * supported by AIO with the old sigevent structure.
         */
        CP(*osig, *nsig, sigev_notify);
        switch (nsig->sigev_notify) {
        case SIGEV_NONE:
                break;
        case SIGEV_SIGNAL:
                nsig->sigev_signo = osig->__sigev_u.__sigev_signo;
                break;
        case SIGEV_KEVENT:
                nsig->sigev_notify_kqueue =
                    osig->__sigev_u.__sigev_notify_kqueue;
                PTRIN_CP(*osig, *nsig, sigev_value.sival_ptr);
                break;
        default:
                return (EINVAL);
        }
        return (0);
}

static int
aiocb32_copyin_old_sigevent(struct aiocb *ujob, struct kaiocb *kjob,
    int type __unused)
{
        struct oaiocb32 job32;
        struct aiocb *kcb = &kjob->uaiocb;
        int error;

        bzero(kcb, sizeof(struct aiocb));
        error = copyin(ujob, &job32, sizeof(job32));
        if (error)
                return (error);

        /* No need to copyin aio_iov, because it did not exist in FreeBSD 6 */

        CP(job32, *kcb, aio_fildes);
        CP(job32, *kcb, aio_offset);
        PTRIN_CP(job32, *kcb, aio_buf);
        CP(job32, *kcb, aio_nbytes);
        CP(job32, *kcb, aio_lio_opcode);
        CP(job32, *kcb, aio_reqprio);
        CP(job32, *kcb, _aiocb_private.status);
        CP(job32, *kcb, _aiocb_private.error);
        return (convert_old_sigevent32(&job32.aio_sigevent,
            &kcb->aio_sigevent));
}
#endif

static int
aiocb32_copyin(struct aiocb *ujob, struct kaiocb *kjob, int type)
{
        struct aiocb32 job32;
        struct aiocb *kcb = &kjob->uaiocb;
        struct iovec32 *iov32;
        int error;

        error = copyin(ujob, &job32, sizeof(job32));
        if (error)
                return (error);
        CP(job32, *kcb, aio_fildes);
        CP(job32, *kcb, aio_offset);
        CP(job32, *kcb, aio_lio_opcode);
        if (type == LIO_NOP)
                type = kcb->aio_lio_opcode;
        if (type & LIO_VECTORED) {
                iov32 = PTRIN(job32.aio_iov);
                CP(job32, *kcb, aio_iovcnt);
                /* malloc a uio and copy in the iovec */
                error = freebsd32_copyinuio(iov32,
                    kcb->aio_iovcnt, &kjob->uiop);
                if (error)
                        return (error);
        } else {
                PTRIN_CP(job32, *kcb, aio_buf);
                CP(job32, *kcb, aio_nbytes);
        }
        CP(job32, *kcb, aio_reqprio);
        CP(job32, *kcb, _aiocb_private.status);
        CP(job32, *kcb, _aiocb_private.error);
        error = convert_sigevent32(&job32.aio_sigevent, &kcb->aio_sigevent);

        return (error);
}

static long
aiocb32_fetch_status(struct aiocb *ujob)
{
        struct aiocb32 *ujob32;

        ujob32 = (struct aiocb32 *)ujob;
        return (fuword32(&ujob32->_aiocb_private.status));
}

static long
aiocb32_fetch_error(struct aiocb *ujob)
{
        struct aiocb32 *ujob32;

        ujob32 = (struct aiocb32 *)ujob;
        return (fuword32(&ujob32->_aiocb_private.error));
}

static int
aiocb32_store_status(struct aiocb *ujob, long status)
{
        struct aiocb32 *ujob32;

        ujob32 = (struct aiocb32 *)ujob;
        return (suword32(&ujob32->_aiocb_private.status, status));
}

static int
aiocb32_store_error(struct aiocb *ujob, long error)
{
        struct aiocb32 *ujob32;

        ujob32 = (struct aiocb32 *)ujob;
        return (suword32(&ujob32->_aiocb_private.error, error));
}

static int
aiocb32_store_aiocb(struct aiocb **ujobp, struct aiocb *ujob)
{

        return (suword32(ujobp, (long)ujob));
}

static struct aiocb_ops aiocb32_ops = {
        .aio_copyin = aiocb32_copyin,
        .fetch_status = aiocb32_fetch_status,
        .fetch_error = aiocb32_fetch_error,
        .store_status = aiocb32_store_status,
        .store_error = aiocb32_store_error,
        .store_aiocb = aiocb32_store_aiocb,
};

#ifdef COMPAT_FREEBSD6
static struct aiocb_ops aiocb32_ops_osigevent = {
        .aio_copyin = aiocb32_copyin_old_sigevent,
        .fetch_status = aiocb32_fetch_status,
        .fetch_error = aiocb32_fetch_error,
        .store_status = aiocb32_store_status,
        .store_error = aiocb32_store_error,
        .store_aiocb = aiocb32_store_aiocb,
};
#endif

int
freebsd32_aio_return(struct thread *td, struct freebsd32_aio_return_args *uap)
{

        return (kern_aio_return(td, (struct aiocb *)uap->aiocbp, &aiocb32_ops));
}

int
freebsd32_aio_suspend(struct thread *td, struct freebsd32_aio_suspend_args *uap)
{
        struct timespec32 ts32;
        struct timespec ts, *tsp;
        struct aiocb **ujoblist;
        uint32_t *ujoblist32;
        int error, i;

        if (uap->nent < 0 || uap->nent > max_aio_queue_per_proc)
                return (EINVAL);

        if (uap->timeout) {
                /* Get timespec struct. */
                if ((error = copyin(uap->timeout, &ts32, sizeof(ts32))) != 0)
                        return (error);
                CP(ts32, ts, tv_sec);
                CP(ts32, ts, tv_nsec);
                tsp = &ts;
        } else
                tsp = NULL;

        ujoblist = malloc(uap->nent * sizeof(ujoblist[0]), M_AIO, M_WAITOK);
        ujoblist32 = (uint32_t *)ujoblist;
        error = copyin(uap->aiocbp, ujoblist32, uap->nent *
            sizeof(ujoblist32[0]));
        if (error == 0) {
                for (i = uap->nent - 1; i >= 0; i--)
                        ujoblist[i] = PTRIN(ujoblist32[i]);

                error = kern_aio_suspend(td, uap->nent, ujoblist, tsp);
        }
        free(ujoblist, M_AIO);
        return (error);
}

int
freebsd32_aio_error(struct thread *td, struct freebsd32_aio_error_args *uap)
{

        return (kern_aio_error(td, (struct aiocb *)uap->aiocbp, &aiocb32_ops));
}

#ifdef COMPAT_FREEBSD6
int
freebsd6_freebsd32_aio_read(struct thread *td,
    struct freebsd6_freebsd32_aio_read_args *uap)
{

        return (aio_aqueue(td, (struct aiocb *)uap->aiocbp, NULL, LIO_READ,
            &aiocb32_ops_osigevent));
}
#endif

int
freebsd32_aio_read(struct thread *td, struct freebsd32_aio_read_args *uap)
{

        return (aio_aqueue(td, (struct aiocb *)uap->aiocbp, NULL, LIO_READ,
            &aiocb32_ops));
}

int
freebsd32_aio_readv(struct thread *td, struct freebsd32_aio_readv_args *uap)
{

        return (aio_aqueue(td, (struct aiocb *)uap->aiocbp, NULL, LIO_READV,
            &aiocb32_ops));
}

#ifdef COMPAT_FREEBSD6
int
freebsd6_freebsd32_aio_write(struct thread *td,
    struct freebsd6_freebsd32_aio_write_args *uap)
{

        return (aio_aqueue(td, (struct aiocb *)uap->aiocbp, NULL, LIO_WRITE,
            &aiocb32_ops_osigevent));
}
#endif

int
freebsd32_aio_write(struct thread *td, struct freebsd32_aio_write_args *uap)
{

        return (aio_aqueue(td, (struct aiocb *)uap->aiocbp, NULL, LIO_WRITE,
            &aiocb32_ops));
}

int
freebsd32_aio_writev(struct thread *td, struct freebsd32_aio_writev_args *uap)
{

        return (aio_aqueue(td, (struct aiocb *)uap->aiocbp, NULL, LIO_WRITEV,
            &aiocb32_ops));
}

int
freebsd32_aio_mlock(struct thread *td, struct freebsd32_aio_mlock_args *uap)
{

        return (aio_aqueue(td, (struct aiocb *)uap->aiocbp, NULL, LIO_MLOCK,
            &aiocb32_ops));
}

int
freebsd32_aio_waitcomplete(struct thread *td,
    struct freebsd32_aio_waitcomplete_args *uap)
{
        struct timespec32 ts32;
        struct timespec ts, *tsp;
        int error;

        if (uap->timeout) {
                /* Get timespec struct. */
                error = copyin(uap->timeout, &ts32, sizeof(ts32));
                if (error)
                        return (error);
                CP(ts32, ts, tv_sec);
                CP(ts32, ts, tv_nsec);
                tsp = &ts;
        } else
                tsp = NULL;

        return (kern_aio_waitcomplete(td, (struct aiocb **)uap->aiocbp, tsp,
            &aiocb32_ops));
}

int
freebsd32_aio_fsync(struct thread *td, struct freebsd32_aio_fsync_args *uap)
{

        return (kern_aio_fsync(td, uap->op, (struct aiocb *)uap->aiocbp,
            &aiocb32_ops));
}

#ifdef COMPAT_FREEBSD6
int
freebsd6_freebsd32_lio_listio(struct thread *td,
    struct freebsd6_freebsd32_lio_listio_args *uap)
{
        struct aiocb **acb_list;
        struct sigevent *sigp, sig;
        struct osigevent32 osig;
        uint32_t *acb_list32;
        int error, i, nent;

        if ((uap->mode != LIO_NOWAIT) && (uap->mode != LIO_WAIT))
                return (EINVAL);

        nent = uap->nent;
        if (nent < 0 || nent > max_aio_queue_per_proc)
                return (EINVAL);

        if (uap->sig && (uap->mode == LIO_NOWAIT)) {
                error = copyin(uap->sig, &osig, sizeof(osig));
                if (error)
                        return (error);
                error = convert_old_sigevent32(&osig, &sig);
                if (error)
                        return (error);
                sigp = &sig;
        } else
                sigp = NULL;

        acb_list32 = malloc(sizeof(uint32_t) * nent, M_LIO, M_WAITOK);
        error = copyin(uap->acb_list, acb_list32, nent * sizeof(uint32_t));
        if (error) {
                free(acb_list32, M_LIO);
                return (error);
        }
        acb_list = malloc(sizeof(struct aiocb *) * nent, M_LIO, M_WAITOK);
        for (i = 0; i < nent; i++)
                acb_list[i] = PTRIN(acb_list32[i]);
        free(acb_list32, M_LIO);

        error = kern_lio_listio(td, uap->mode,
            (struct aiocb * const *)uap->acb_list, acb_list, nent, sigp,
            &aiocb32_ops_osigevent);
        free(acb_list, M_LIO);
        return (error);
}
#endif

int
freebsd32_lio_listio(struct thread *td, struct freebsd32_lio_listio_args *uap)
{
        struct aiocb **acb_list;
        struct sigevent *sigp, sig;
        struct sigevent32 sig32;
        uint32_t *acb_list32;
        int error, i, nent;

        if ((uap->mode != LIO_NOWAIT) && (uap->mode != LIO_WAIT))
                return (EINVAL);

        nent = uap->nent;
        if (nent < 0 || nent > max_aio_queue_per_proc)
                return (EINVAL);

        if (uap->sig && (uap->mode == LIO_NOWAIT)) {
                error = copyin(uap->sig, &sig32, sizeof(sig32));
                if (error)
                        return (error);
                error = convert_sigevent32(&sig32, &sig);
                if (error)
                        return (error);
                sigp = &sig;
        } else
                sigp = NULL;

        acb_list32 = malloc(sizeof(uint32_t) * nent, M_LIO, M_WAITOK);
        error = copyin(uap->acb_list, acb_list32, nent * sizeof(uint32_t));
        if (error) {
                free(acb_list32, M_LIO);
                return (error);
        }
        acb_list = malloc(sizeof(struct aiocb *) * nent, M_LIO, M_WAITOK);
        for (i = 0; i < nent; i++)
                acb_list[i] = PTRIN(acb_list32[i]);
        free(acb_list32, M_LIO);

        error = kern_lio_listio(td, uap->mode,
            (struct aiocb * const *)uap->acb_list, acb_list, nent, sigp,
            &aiocb32_ops);
        free(acb_list, M_LIO);
        return (error);
}

#endif