source: vbox/trunk/src/VBox/Runtime/r0drv/solaris/vbi/i86pc/os/vbi.c@ 37948

/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */
/*
 * Copyright 2010-2011 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

/*
 * Private interfaces for VirtualBox access to Solaris kernel internal
 * facilities.
 *
 * See sys/vbi.h for what each function does.
 */

#include <sys/kmem.h>
#include <sys/types.h>
#include <sys/mman.h>
#include <sys/thread.h>
#include <sys/mutex.h>
#include <sys/condvar.h>
#include <sys/sdt.h>
#include <sys/schedctl.h>
#include <sys/time.h>
#include <sys/sysmacros.h>
#include <sys/cmn_err.h>
#include <sys/vmsystm.h>
#include <sys/cyclic.h>
#include <sys/class.h>
#include <sys/cpuvar.h>
#include <sys/kobj.h>
#include <sys/x_call.h>
#include <sys/x86_archext.h>
#include <vm/hat.h>
#include <vm/seg_vn.h>
#include <vm/seg_kmem.h>
#include <sys/ddi.h>
#include <sys/sunddi.h>
#include <sys/modctl.h>
#include <sys/machparam.h>
#include <sys/utsname.h>

#include <iprt/assert.h>

#include "vbi.h"

#define VBIPROC() ((proc_t *)vbi_proc())

/*
 * We have to use dl_lookup to find contig_free().
 */
extern void *contig_alloc(size_t, ddi_dma_attr_t *, uintptr_t, int);
extern void contig_free(void *, size_t);
#pragma weak contig_free
static void (*p_contig_free)(void *, size_t) = contig_free;

/*
 * We have to use dl_lookup to find kflt_init() and thereby use kernel pages from
 * the freelists if we no longer get user pages from freelist and cachelists.
 */
/* Introduced in v9 */
static int use_kflt = 0;
static page_t *vbi_page_get_fromlist(uint_t freelist, caddr_t virtAddr, size_t pgsize);


/*
 * Workarounds for running on old versions of solaris with different cross call
 * interfaces. If we find xc_init_cpu() in the kernel, then just use the defined
 * interfaces for xc_call() from the include file where the xc_call()
 * interfaces just takes a pointer to a ulong_t array. The array must be long
 * enough to hold "ncpus" bits at runtime.

 * The reason for the hacks is that using the type "cpuset_t" is pretty much
 * impossible from code built outside the Solaris source repository that wants
 * to run on multiple releases of Solaris.
 *
 * For old style xc_call()s, 32 bit solaris and older 64 bit versions use
 * "ulong_t" as cpuset_t.
 *
 * Later versions of 64 bit Solaris used: struct {ulong_t words[x];}
 * where "x" depends on NCPU.
 *
 * We detect the difference in 64 bit support by checking the kernel value of
 * max_cpuid, which always holds the compiled value of NCPU - 1.
 *
 * If Solaris increases NCPU to more than 256, this module will continue
 * to work on all versions of Solaris as long as the number of installed
 * CPUs in the machine is <= VBI_NCPU. If VBI_NCPU is increased, this code
 * has to be re-written some to provide compatibility with older Solaris which
 * expects cpuset_t to be based on NCPU==256 -- or we discontinue support
 * of old Nevada/S10.
 */
static int use_old = 0;
static int use_old_with_ulong = 0;
static void (*p_xc_call)() = (void (*)())xc_call;

#define VBI_NCPU        256
#define VBI_SET_WORDS   (VBI_NCPU / (sizeof (ulong_t) * 8))
typedef struct vbi_cpuset {
        ulong_t words[VBI_SET_WORDS];
} vbi_cpuset_t;
#define X_CALL_HIPRI    (2)     /* for old Solaris interface */

/*
 * module linkage stuff
 */
#if 0
static struct modlmisc vbi_modlmisc = {
        &mod_miscops, "VirtualBox Interfaces V8"
};

static struct modlinkage vbi_modlinkage = {
        MODREV_1, { (void *)&vbi_modlmisc, NULL }
};
#endif

extern uintptr_t kernelbase;
#define IS_KERNEL(v)    ((uintptr_t)(v) >= kernelbase)

#if 0
static int vbi_verbose = 0;

#define VBI_VERBOSE(msg) {if (vbi_verbose) cmn_err(CE_WARN, msg);}
#endif

/* Introduced in v8 */
static int vbi_is_initialized = 0;

/* Introduced in v6 */
static int vbi_is_nevada = 0;

#ifdef _LP64
/* 64-bit Solaris 10 offsets */
/* CPU */
static int off_s10_cpu_runrun   = 232;
static int off_s10_cpu_kprunrun = 233;
/* kthread_t */
static int off_s10_t_preempt    = 42;

/* 64-bit Solaris 11 (Nevada/OpenSolaris) offsets */
/* CPU */
static int off_s11_cpu_runrun   = 216;
static int off_s11_cpu_kprunrun = 217;
/* kthread_t */
static int off_s11_t_preempt    = 42;

/* 64-bit Solaris 11 snv_166+ offsets (CR 7037143) */
static int off_s11_t_preempt_new = 48;
#else
/* 32-bit Solaris 10 offsets */
/* CPU */
static int off_s10_cpu_runrun   = 124;
static int off_s10_cpu_kprunrun = 125;
/* kthread_t */
static int off_s10_t_preempt    = 26;

/* 32-bit Solaris 11 (Nevada/OpenSolaris) offsets */
/* CPU */
static int off_s11_cpu_runrun   = 112;
static int off_s11_cpu_kprunrun = 113;
/* kthread_t */
static int off_s11_t_preempt    = 26;
#endif


/* Which offsets will be used */
static int off_cpu_runrun       = -1;
static int off_cpu_kprunrun     = -1;
static int off_t_preempt        = -1;

#define VBI_T_PREEMPT            (*((char *)curthread + off_t_preempt))
#define VBI_CPU_KPRUNRUN         (*((char *)CPU + off_cpu_kprunrun))
#define VBI_CPU_RUNRUN           (*((char *)CPU + off_cpu_runrun))

#undef kpreempt_disable
#undef kpreempt_enable

#define VBI_PREEMPT_DISABLE()                   \
        {                                                                       \
                VBI_T_PREEMPT++;                                \
                ASSERT(VBI_T_PREEMPT >= 1);             \
        }
#define VBI_PREEMPT_ENABLE()                    \
        {                                                                       \
                ASSERT(VBI_T_PREEMPT >= 1);             \
                if (--VBI_T_PREEMPT == 0 &&     \
                    VBI_CPU_RUNRUN)                             \
                        kpreempt(KPREEMPT_SYNC);        \
        }

/* End of v6 intro */

#if 0
int
_init(void)
{
        int err = vbi_init();
        if (!err)
                err = mod_install(&vbi_modlinkage);
        return (err);
}
#endif

int
vbi_init(void)
{
        /*
         * Check to see if this version of virtualbox interface module will work
         * with the kernel.
         */
        if (kobj_getsymvalue("xc_init_cpu", 1) != NULL) {
                /*
                 * Our bit vector storage needs to be large enough for the
                 * actual number of CPUs running in the system.
                 */
                if (ncpus > VBI_NCPU) {
                        cmn_err(CE_NOTE, "cpu count mismatch.\n");
                        return (EINVAL);
                }
        } else {
                use_old = 1;
                if (max_cpuid + 1 == sizeof(ulong_t) * 8)
                        use_old_with_ulong = 1;
                else if (max_cpuid + 1 != VBI_NCPU)
                {
                        cmn_err(CE_NOTE, "cpuset_t size mismatch. probably too old a kernel.\n");
                        return (EINVAL);        /* cpuset_t size mismatch */
                }
        }

        /*
         * In older versions of Solaris contig_free() is a static routine.
         */
        if (p_contig_free == NULL) {
                p_contig_free = (void (*)(void *, size_t))
                        kobj_getsymvalue("contig_free", 1);
                if (p_contig_free == NULL) {
                        cmn_err(CE_NOTE, " contig_free() not found in kernel\n");
                        return (EINVAL);
                }
        }

        /*
         * Use kernel page freelist flags to get pages from kernel page freelists
         * while allocating physical pages, once the userpages are exhausted.
         * snv_161+, see @bugref{5632}.
         */
        if (kobj_getsymvalue("kflt_init", 1) != NULL)
        {
                int *p_kflt_disable = (int*)kobj_getsymvalue("kflt_disable", 1);        /* amd64 only, on 32-bit kflt's are disabled. */
                if (p_kflt_disable && *p_kflt_disable == 0)
                {
                        use_kflt = 1;
                }
        }


        /*
         * Check if this is S10 or Nevada
         */
        if (!strncmp(utsname.release, "5.11", sizeof("5.11") - 1)) {
                /* Nevada detected... */
                vbi_is_nevada = 1;

                off_cpu_runrun = off_s11_cpu_runrun;
                off_cpu_kprunrun = off_s11_cpu_kprunrun;
                off_t_preempt = off_s11_t_preempt;

#ifdef _LP64
                /* Only 64-bit kernels */
                long snv_version = 0;
                if (  !strncmp(utsname.version, "snv_", 4)
                        && strlen(utsname.version) > 4)
                {
                        ddi_strtol(utsname.version + 4, NULL /* endptr */, 0, &snv_version);
                        if (snv_version >= 166)
                        {
                                off_t_preempt = off_s11_t_preempt_new;
                                cmn_err(CE_NOTE,  "here\n");
                        }

                        cmn_err(CE_NOTE, "Detected S11 version %ld: Preemption offset=%d\n", snv_version, off_t_preempt);
                }
                else
                        cmn_err(CE_NOTE, "WARNING!! Cannot determine version. Assuming pre snv_166. Preemption offset=%ld may be busted!\n", off_t_preempt);
#endif
        } else {
                /* Solaris 10 detected... */
                vbi_is_nevada = 0;

                off_cpu_runrun = off_s10_cpu_runrun;
                off_cpu_kprunrun = off_s10_cpu_kprunrun;
                off_t_preempt = off_s10_t_preempt;
        }

        /*
         * Sanity checking...
         */
        /* CPU */
        char crr = VBI_CPU_RUNRUN;
        char krr = VBI_CPU_KPRUNRUN;
        if (   (crr < 0 || crr > 1)
                || (krr < 0 || krr > 1)) {
                cmn_err(CE_NOTE, ":CPU structure sanity check failed! OS version mismatch.\n");
                return EINVAL;
        }

        /* Thread */
        char t_preempt = VBI_T_PREEMPT;
        if (t_preempt < 0 || t_preempt > 32) {
                cmn_err(CE_NOTE, ":Thread structure sanity check failed! OS version mismatch.\n");
                return EINVAL;
        }

        vbi_is_initialized = 1;

        return (0);
}

#if 0
int
_fini(void)
{
        int err = mod_remove(&vbi_modlinkage);
        if (err != 0)
                return (err);

        return (0);
}

int
_info(struct modinfo *modinfop)
{
        return (mod_info(&vbi_modlinkage, modinfop));
}
#endif


static ddi_dma_attr_t base_attr = {
        DMA_ATTR_V0,            /* Version Number */
        (uint64_t)0,            /* lower limit */
        (uint64_t)0,            /* high limit */
        (uint64_t)0xffffffff,   /* counter limit */
        (uint64_t)PAGESIZE,     /* pagesize alignment */
        (uint64_t)PAGESIZE,     /* pagesize burst size */
        (uint64_t)PAGESIZE,     /* pagesize effective DMA size */
        (uint64_t)0xffffffff,   /* max DMA xfer size */
        (uint64_t)0xffffffff,   /* segment boundary */
        1,                      /* list length (1 for contiguous) */
        1,                      /* device granularity */
        0                       /* bus-specific flags */
};

static void *
vbi_internal_alloc(uint64_t *phys, size_t size, uint64_t alignment, int contig)
{
        ddi_dma_attr_t attr;
        pfn_t pfn;
        void *ptr;
        uint_t npages;

        if ((size & PAGEOFFSET) != 0)
                return (NULL);
        npages = (size + PAGESIZE - 1) >> PAGESHIFT;
        if (npages == 0)
                return (NULL);

        attr = base_attr;
        attr.dma_attr_addr_hi = *phys;
        attr.dma_attr_align   = alignment;
        if (!contig)
                attr.dma_attr_sgllen = npages;
        ptr = contig_alloc(size, &attr, PAGESIZE, 1);

        if (ptr == NULL) {
                cmn_err(CE_NOTE, "vbi_internal_alloc() failure for %lu bytes contig=%d", size, contig);
                return (NULL);
        }

        pfn = hat_getpfnum(kas.a_hat, (caddr_t)ptr);
        if (pfn == PFN_INVALID)
                panic("vbi_contig_alloc(): hat_getpfnum() failed\n");
        *phys = (uint64_t)pfn << PAGESHIFT;
        return (ptr);
}

void *
vbi_contig_alloc(uint64_t *phys, size_t size)
{
        /* Obsolete */
        return (vbi_internal_alloc(phys, size, PAGESIZE /* alignment */, 1 /* contiguous */));
}

void
vbi_contig_free(void *va, size_t size)
{
        /* Obsolete */
        p_contig_free(va, size);
}

void *
vbi_kernel_map(uint64_t pa, size_t size, uint_t prot)
{
        caddr_t va;

        if ((pa & PAGEOFFSET) || (size & PAGEOFFSET)) {
                cmn_err(CE_NOTE, "vbi_kernel_map() bad pa (0x%lx) or size (%lu)", pa, size);
                return (NULL);
        }

        va = vmem_alloc(heap_arena, size, VM_SLEEP);

        hat_devload(kas.a_hat, va, size, (pfn_t)(pa >> PAGESHIFT),
                prot, HAT_LOAD | HAT_LOAD_LOCK | HAT_UNORDERED_OK);

        return (va);
}

void
vbi_unmap(void *va, size_t size)
{
        if (IS_KERNEL(va)) {
                hat_unload(kas.a_hat, va, size, HAT_UNLOAD | HAT_UNLOAD_UNLOCK);
                vmem_free(heap_arena, va, size);
        } else {
                struct as *as = VBIPROC()->p_as;

                as_rangelock(as);
                (void) as_unmap(as, va, size);
                as_rangeunlock(as);
        }
}

void *
vbi_curthread(void)
{
        return (curthread);
}

int
vbi_yield(void)
{
        int rv = 0;

        vbi_preempt_disable();

        char tpr = VBI_T_PREEMPT;
        char kpr = VBI_CPU_KPRUNRUN;
        if (tpr == 1 && kpr)
                rv = 1;

        vbi_preempt_enable();
        return (rv);
}

uint64_t
vbi_timer_granularity(void)
{
        return (nsec_per_tick);
}

typedef struct vbi_timer {
        cyc_handler_t   vbi_handler;
        cyclic_id_t     vbi_cyclic;
        uint64_t        vbi_interval;
        void            (*vbi_func)();
        void            *vbi_arg1;
        void            *vbi_arg2;
} vbi_timer_t;

static void
vbi_timer_callback(void *arg)
{
        vbi_timer_t *t = arg;

        if (t->vbi_interval == 0)
                vbi_timer_stop(arg);
        t->vbi_func(t->vbi_arg1, t->vbi_arg2);
}

void *
vbi_timer_create(void *callback, void *arg1, void *arg2, uint64_t interval)
{
        vbi_timer_t *t = kmem_zalloc(sizeof (*t), KM_SLEEP);

        t->vbi_func = (void (*)())callback;
        t->vbi_arg1 = arg1;
        t->vbi_arg2 = arg2;
        t->vbi_handler.cyh_func = vbi_timer_callback;
        t->vbi_handler.cyh_arg = (void *)t;
        t->vbi_handler.cyh_level = CY_LOCK_LEVEL;
        t->vbi_cyclic = CYCLIC_NONE;
        t->vbi_interval = interval;
        return (t);
}

void
vbi_timer_destroy(void *timer)
{
        vbi_timer_t *t = timer;
        if (t != NULL) {
                vbi_timer_stop(timer);
                kmem_free(t, sizeof (*t));
        }
}

void
vbi_timer_start(void *timer, uint64_t when)
{
        vbi_timer_t *t = timer;
        cyc_time_t fire_time;
        uint64_t interval = t->vbi_interval;

        mutex_enter(&cpu_lock);
        when += gethrtime();
        fire_time.cyt_when = when;
        if (interval == 0)
                fire_time.cyt_interval = when;
        else
                fire_time.cyt_interval = interval;
        t->vbi_cyclic = cyclic_add(&t->vbi_handler, &fire_time);
        mutex_exit(&cpu_lock);
}

void
vbi_timer_stop(void *timer)
{
        vbi_timer_t *t = timer;

        if (t->vbi_cyclic == CYCLIC_NONE)
                return;
        mutex_enter(&cpu_lock);
        if (t->vbi_cyclic != CYCLIC_NONE) {
                cyclic_remove(t->vbi_cyclic);
                t->vbi_cyclic = CYCLIC_NONE;
        }
        mutex_exit(&cpu_lock);
}

uint64_t
vbi_tod(void)
{
        timestruc_t ts;

        mutex_enter(&tod_lock);
        ts = tod_get();
        mutex_exit(&tod_lock);
        return ((uint64_t)ts.tv_sec * 1000000000 + ts.tv_nsec);
}


void *
vbi_proc(void)
{
        proc_t *p;
        drv_getparm(UPROCP, &p);
        return (p);
}

void
vbi_set_priority(void *thread, int priority)
{
        kthread_t *t = thread;

        thread_lock(t);
        (void) thread_change_pri(t, priority, 0);
        thread_unlock(t);
}

void *
vbi_thread_create(void (*func)(void *), void *arg, size_t len, int priority)
{
        kthread_t *t;

        t = thread_create(NULL, NULL, (void (*)())func, arg, len,
                VBIPROC(), TS_RUN, priority);
        return (t);
}

void
vbi_thread_exit(void)
{
        thread_exit();
}

void *
vbi_text_alloc(size_t size)
{
        return (segkmem_alloc(heaptext_arena, size, KM_SLEEP));
}

void
vbi_text_free(void *va, size_t size)
{
        segkmem_free(heaptext_arena, va, size);
}

int
vbi_cpu_id(void)
{
        return (CPU->cpu_id);
}

int
vbi_max_cpu_id(void)
{
        return (max_cpuid);
}

int
vbi_cpu_maxcount(void)
{
        return (max_cpuid + 1);
}

int
vbi_cpu_count(void)
{
        return (ncpus);
}

int
vbi_cpu_online(int c)
{
        int x;

        mutex_enter(&cpu_lock);
        x = cpu_is_online(cpu[c]);
        mutex_exit(&cpu_lock);
        return (x);
}

void
vbi_preempt_disable(void)
{
        VBI_PREEMPT_DISABLE();
}

void
vbi_preempt_enable(void)
{
        VBI_PREEMPT_ENABLE();
}

void
vbi_execute_on_all(void *func, void *arg)
{
        vbi_cpuset_t set;
        int i;

        for (i = 0; i < VBI_SET_WORDS; ++i)
                set.words[i] = (ulong_t)-1L;
        if (use_old) {
                if (use_old_with_ulong) {
                        p_xc_call((xc_arg_t)arg, 0, 0, X_CALL_HIPRI,
                                set.words[0], (xc_func_t)func);
                } else {
                        p_xc_call((xc_arg_t)arg, 0, 0, X_CALL_HIPRI,
                                set, (xc_func_t)func);
                }
        } else {
                xc_call((xc_arg_t)arg, 0, 0, &set.words[0], (xc_func_t)func);
        }
}

void
vbi_execute_on_others(void *func, void *arg)
{
        vbi_cpuset_t set;
        int i;

        for (i = 0; i < VBI_SET_WORDS; ++i)
                set.words[i] = (ulong_t)-1L;
        BT_CLEAR(set.words, vbi_cpu_id());
        if (use_old) {
                if (use_old_with_ulong) {
                        p_xc_call((xc_arg_t)arg, 0, 0, X_CALL_HIPRI,
                                set.words[0], (xc_func_t)func);
                } else {
                        p_xc_call((xc_arg_t)arg, 0, 0, X_CALL_HIPRI,
                                set, (xc_func_t)func);
                }
        } else {
                xc_call((xc_arg_t)arg, 0, 0, &set.words[0], (xc_func_t)func);
        }
}

void
vbi_execute_on_one(void *func, void *arg, int c)
{
        vbi_cpuset_t set;
        int i;

        for (i = 0; i < VBI_SET_WORDS; ++i)
                set.words[i] = 0;
        BT_SET(set.words, c);
        if (use_old) {
                if (use_old_with_ulong) {
                        p_xc_call((xc_arg_t)arg, 0, 0, X_CALL_HIPRI,
                                set.words[0], (xc_func_t)func);
                } else {
                        p_xc_call((xc_arg_t)arg, 0, 0, X_CALL_HIPRI,
                                set, (xc_func_t)func);
                }
        } else {
                xc_call((xc_arg_t)arg, 0, 0, &set.words[0], (xc_func_t)func);
        }
}

int
vbi_lock_va(void *addr, size_t len, int access, void **handle)
{
        faultcode_t err;

        /*
         * kernel mappings on x86 are always locked, so only handle user.
         */
        *handle = NULL;
        if (!IS_KERNEL(addr)) {
                err = as_fault(VBIPROC()->p_as->a_hat, VBIPROC()->p_as,
                        (caddr_t)addr, len, F_SOFTLOCK, access);
                if (err != 0) {
                        cmn_err(CE_NOTE, "vbi_lock_va() failed to lock");
                        return (-1);
                }
        }
        return (0);
}

/*ARGSUSED*/
void
vbi_unlock_va(void *addr, size_t len, int access, void *handle)
{
        if (!IS_KERNEL(addr))
                as_fault(VBIPROC()->p_as->a_hat, VBIPROC()->p_as,
                        (caddr_t)addr, len, F_SOFTUNLOCK, access);
}

uint64_t
vbi_va_to_pa(void *addr)
{
        struct hat *hat;
        pfn_t pfn;
        uintptr_t v = (uintptr_t)addr;

        if (IS_KERNEL(v))
                hat = kas.a_hat;
        else
                hat = VBIPROC()->p_as->a_hat;
        pfn = hat_getpfnum(hat, (caddr_t)(v & PAGEMASK));
        if (pfn == PFN_INVALID)
                return (-(uint64_t)1);
        return (((uint64_t)pfn << PAGESHIFT) | (v & PAGEOFFSET));
}


struct segvbi_crargs {
        uint64_t *palist;
        uint_t prot;
};

struct segvbi_data {
        uint_t prot;
};

static struct seg_ops segvbi_ops;

static int
segvbi_create(struct seg *seg, void *args)
{
        struct segvbi_crargs *a = args;
        struct segvbi_data *data;
        struct as *as = seg->s_as;
        caddr_t va;
        ulong_t pgcnt;
        ulong_t p;

        hat_map(as->a_hat, seg->s_base, seg->s_size, HAT_MAP);
        data = kmem_zalloc(sizeof (*data), KM_SLEEP);
        data->prot = a->prot | PROT_USER;

        seg->s_ops = &segvbi_ops;
        seg->s_data = data;

        /*
         * now load locked mappings to the pages
         */
        va = seg->s_base;
        pgcnt = (seg->s_size + PAGESIZE - 1) >> PAGESHIFT;
        for (p = 0; p < pgcnt; ++p, va += PAGESIZE) {
                hat_devload(as->a_hat, va,
                        PAGESIZE, a->palist[p] >> PAGESHIFT,
                        data->prot | HAT_UNORDERED_OK, HAT_LOAD | HAT_LOAD_LOCK);
        }

        return (0);
}

/*
 * Duplicate a seg and return new segment in newseg.
 */
static int
segvbi_dup(struct seg *seg, struct seg *newseg)
{
        struct segvbi_data *data = seg->s_data;
        struct segvbi_data *ndata;

        ndata = kmem_zalloc(sizeof (*data), KM_SLEEP);
        ndata->prot = data->prot;
        newseg->s_ops = &segvbi_ops;
        newseg->s_data = ndata;

        return (0);
}

static int
segvbi_unmap(struct seg *seg, caddr_t addr, size_t len)
{
        if (addr < seg->s_base || addr + len > seg->s_base + seg->s_size ||
                (len & PAGEOFFSET) || ((uintptr_t)addr & PAGEOFFSET))
                panic("segvbi_unmap");

        if (addr != seg->s_base || len != seg->s_size)
                return (ENOTSUP);

        hat_unload(seg->s_as->a_hat, addr, len,
                HAT_UNLOAD_UNMAP | HAT_UNLOAD_UNLOCK);

        seg_free(seg);
        return (0);
}

static void
segvbi_free(struct seg *seg)
{
        struct segvbi_data *data = seg->s_data;
        kmem_free(data, sizeof (*data));
}

/*
 * We would demand fault if the (u)read() path would SEGOP_FAULT()
 * on buffers mapped in via vbi_user_map() i.e. prefaults before DMA.
 * Don't fail in such case where we're called directly, see #5047.
 */
static int
segvbi_fault(struct hat *hat, struct seg *seg, caddr_t addr, size_t len,
        enum fault_type type, enum seg_rw rw)
{
        return (0);
}

static int
segvbi_faulta(struct seg *seg, caddr_t addr)
{
        return (0);
}

static int
segvbi_setprot(struct seg *seg, caddr_t addr, size_t len, uint_t prot)
{
        return (EACCES);
}

static int
segvbi_checkprot(struct seg *seg, caddr_t addr, size_t len, uint_t prot)
{
        return (EINVAL);
}

static int
segvbi_kluster(struct seg *seg, caddr_t addr, ssize_t delta)
{
        return (-1);
}

static int
segvbi_sync(struct seg *seg, caddr_t addr, size_t len, int attr, uint_t flags)
{
        return (0);
}

static size_t
segvbi_incore(struct seg *seg, caddr_t addr, size_t len, char *vec)
{
        size_t v;

        for (v = 0, len = (len + PAGEOFFSET) & PAGEMASK; len;
                len -= PAGESIZE, v += PAGESIZE)
                *vec++ = 1;
        return (v);
}

static int
segvbi_lockop(struct seg *seg, caddr_t addr,
        size_t len, int attr, int op, ulong_t *lockmap, size_t pos)
{
        return (0);
}

static int
segvbi_getprot(struct seg *seg, caddr_t addr, size_t len, uint_t *protv)
{
        struct segvbi_data *data = seg->s_data;
        size_t pgno = seg_page(seg, addr + len) - seg_page(seg, addr) + 1;
        if (pgno != 0)
        {
                do
                {
                        pgno--;
                        protv[pgno] = data->prot;
                } while (pgno != 0);
        }
        return (0);
}

static u_offset_t
segvbi_getoffset(struct seg *seg, caddr_t addr)
{
        return ((uintptr_t)addr - (uintptr_t)seg->s_base);
}

static int
segvbi_gettype(struct seg *seg, caddr_t addr)
{
        return (MAP_SHARED);
}

static vnode_t vbivp;

static int
segvbi_getvp(struct seg *seg, caddr_t addr, struct vnode **vpp)
{
        *vpp = &vbivp;
        return (0);
}

static int
segvbi_advise(struct seg *seg, caddr_t addr, size_t len, uint_t behav)
{
        return (0);
}

static void
segvbi_dump(struct seg *seg)
{}

static int
segvbi_pagelock(struct seg *seg, caddr_t addr, size_t len,
        struct page ***ppp, enum lock_type type, enum seg_rw rw)
{
        return (ENOTSUP);
}

static int
segvbi_setpagesize(struct seg *seg, caddr_t addr, size_t len, uint_t szc)
{
        return (ENOTSUP);
}

static int
segvbi_getmemid(struct seg *seg, caddr_t addr, memid_t *memid)
{
        return (ENODEV);
}

static lgrp_mem_policy_info_t *
segvbi_getpolicy(struct seg *seg, caddr_t addr)
{
        return (NULL);
}

static int
segvbi_capable(struct seg *seg, segcapability_t capability)
{
        return (0);
}

static struct seg_ops segvbi_ops = {
        segvbi_dup,
        segvbi_unmap,
        segvbi_free,
        segvbi_fault,
        segvbi_faulta,
        segvbi_setprot,
        segvbi_checkprot,
        (int (*)())segvbi_kluster,
        (size_t (*)(struct seg *))NULL, /* swapout */
        segvbi_sync,
        segvbi_incore,
        segvbi_lockop,
        segvbi_getprot,
        segvbi_getoffset,
        segvbi_gettype,
        segvbi_getvp,
        segvbi_advise,
        segvbi_dump,
        segvbi_pagelock,
        segvbi_setpagesize,
        segvbi_getmemid,
        segvbi_getpolicy,
        segvbi_capable
};



/*
 * Interfaces to inject physical pages into user address space
 * and later remove them.
 */
int
vbi_user_map(caddr_t *va, uint_t prot, uint64_t *palist, size_t len)
{
        struct as *as = VBIPROC()->p_as;
        struct segvbi_crargs args;
        int error = 0;

        args.palist = palist;
        args.prot = prot;
        as_rangelock(as);
        map_addr(va, len, 0, 0, MAP_SHARED);
        if (*va != NULL)
                error = as_map(as, *va, len, segvbi_create, &args);
        else
                error = ENOMEM;
        if (error)
                cmn_err(CE_NOTE, "vbi_user_map() failed error=%d", error);
        as_rangeunlock(as);
        return (error);
}


/*
 * This is revision 2 of the interface.
 */

struct vbi_cpu_watch {
        void (*vbi_cpu_func)(void *, int, int);
        void *vbi_cpu_arg;
};

static int
vbi_watcher(cpu_setup_t state, int icpu, void *arg)
{
        vbi_cpu_watch_t *w = arg;
        int online;

        if (state == CPU_ON)
                online = 1;
        else if (state == CPU_OFF)
                online = 0;
        else
                return (0);
        w->vbi_cpu_func(w->vbi_cpu_arg, icpu, online);
        return (0);
}

vbi_cpu_watch_t *
vbi_watch_cpus(void (*func)(void *, int, int), void *arg, int current_too)
{
        int c;
        vbi_cpu_watch_t *w;

        w = kmem_alloc(sizeof (*w), KM_SLEEP);
        w->vbi_cpu_func = func;
        w->vbi_cpu_arg = arg;
        mutex_enter(&cpu_lock);
        register_cpu_setup_func(vbi_watcher, w);
        if (current_too) {
                for (c = 0; c < ncpus; ++c) {
                        if (cpu_is_online(cpu[c]))
                                func(arg, c, 1);
                }
        }
        mutex_exit(&cpu_lock);
        return (w);
}

void
vbi_ignore_cpus(vbi_cpu_watch_t *w)
{
        mutex_enter(&cpu_lock);
        unregister_cpu_setup_func(vbi_watcher, w);
        mutex_exit(&cpu_lock);
        kmem_free(w, sizeof (*w));
}

/*
 * Simple timers are pretty much a pass through to the cyclic subsystem.
 */
struct vbi_stimer {
        cyc_handler_t   s_handler;
        cyc_time_t      s_fire_time;
        cyclic_id_t     s_cyclic;
        uint64_t        s_tick;
        void            (*s_func)(void *, uint64_t);
        void            *s_arg;
};

static void
vbi_stimer_func(void *arg)
{
        vbi_stimer_t *t = arg;
        t->s_func(t->s_arg, ++t->s_tick);
}

extern vbi_stimer_t *
vbi_stimer_begin(
        void (*func)(void *, uint64_t),
        void *arg,
        uint64_t when,
        uint64_t interval,
        int on_cpu)
{
        vbi_stimer_t *t = kmem_zalloc(sizeof (*t), KM_SLEEP);

        t->s_handler.cyh_func = vbi_stimer_func;
        t->s_handler.cyh_arg = t;
        t->s_handler.cyh_level = CY_LOCK_LEVEL;
        t->s_tick = 0;
        t->s_func = func;
        t->s_arg = arg;

        mutex_enter(&cpu_lock);
        if (on_cpu != VBI_ANY_CPU && !cpu_is_online(cpu[on_cpu])) {
                t = NULL;
                goto done;
        }

        when += gethrtime();
        t->s_fire_time.cyt_when = when;
        if (interval == 0)
                t->s_fire_time.cyt_interval = INT64_MAX - when;
        else
                t->s_fire_time.cyt_interval = interval;
        t->s_cyclic = cyclic_add(&t->s_handler, &t->s_fire_time);
        if (on_cpu != VBI_ANY_CPU)
                cyclic_bind(t->s_cyclic, cpu[on_cpu], NULL);
done:
        mutex_exit(&cpu_lock);
        return (t);
}

extern void
vbi_stimer_end(vbi_stimer_t *t)
{
        mutex_enter(&cpu_lock);
        cyclic_remove(t->s_cyclic);
        mutex_exit(&cpu_lock);
        kmem_free(t, sizeof (*t));
}

/*
 * Global timers are more complicated. They include a counter on the callback,
 * that indicates the first call on a given cpu.
 */
struct vbi_gtimer {
        uint64_t        *g_counters;
        void            (*g_func)(void *, uint64_t);
        void            *g_arg;
        uint64_t        g_when;
        uint64_t        g_interval;
        cyclic_id_t     g_cyclic;
};

static void
vbi_gtimer_func(void *arg)
{
        vbi_gtimer_t *t = arg;
        t->g_func(t->g_arg, ++t->g_counters[vbi_cpu_id()]);
}

/*
 * Whenever a cpu is onlined, need to reset the g_counters[] for it to zero.
 */
static void
vbi_gtimer_online(void *arg, cpu_t *pcpu, cyc_handler_t *h, cyc_time_t *ct)
{
        vbi_gtimer_t *t = arg;
        hrtime_t now;

        t->g_counters[pcpu->cpu_id] = 0;
        h->cyh_func = vbi_gtimer_func;
        h->cyh_arg = t;
        h->cyh_level = CY_LOCK_LEVEL;
        now = gethrtime();
        if (t->g_when < now)
                ct->cyt_when = now + t->g_interval / 2;
        else
                ct->cyt_when = t->g_when;
        ct->cyt_interval = t->g_interval;
}


vbi_gtimer_t *
vbi_gtimer_begin(
        void (*func)(void *, uint64_t),
        void *arg,
        uint64_t when,
        uint64_t interval)
{
        vbi_gtimer_t *t;
        cyc_omni_handler_t omni;

        /*
         * one shot global timer is not supported yet.
         */
        if (interval == 0)
                return (NULL);

        t = kmem_zalloc(sizeof (*t), KM_SLEEP);
        t->g_counters = kmem_zalloc(ncpus * sizeof (uint64_t), KM_SLEEP);
        t->g_when = when + gethrtime();
        t->g_interval = interval;
        t->g_arg = arg;
        t->g_func = func;
        t->g_cyclic = CYCLIC_NONE;

        omni.cyo_online = (void (*)(void *, cpu_t *, cyc_handler_t *, cyc_time_t *))vbi_gtimer_online;
        omni.cyo_offline = NULL;
        omni.cyo_arg = t;

        mutex_enter(&cpu_lock);
        t->g_cyclic = cyclic_add_omni(&omni);
        mutex_exit(&cpu_lock);
        return (t);
}

extern void
vbi_gtimer_end(vbi_gtimer_t *t)
{
        mutex_enter(&cpu_lock);
        cyclic_remove(t->g_cyclic);
        mutex_exit(&cpu_lock);
        kmem_free(t->g_counters, ncpus * sizeof (uint64_t));
        kmem_free(t, sizeof (*t));
}

int
vbi_is_preempt_enabled(void)
{
        if (vbi_is_initialized) {
                char tpr = VBI_T_PREEMPT;
                return (tpr == 0);
        } else {
                cmn_err(CE_NOTE, "vbi_is_preempt_enabled: called without initializing vbi!\n");
                return 1;
        }
}

void
vbi_poke_cpu(int c)
{
        if (c < ncpus)
                poke_cpu(c);
}

/*
 * This is revision 5 of the interface.
 */

void *
vbi_lowmem_alloc(uint64_t phys, size_t size)
{
        return (vbi_internal_alloc(&phys, size, PAGESIZE /* alignment */, 0 /* non-contiguous */));
}

void
vbi_lowmem_free(void *va, size_t size)
{
        p_contig_free(va, size);
}

/*
 * This is revision 6 of the interface.
 */

int
vbi_is_preempt_pending(void)
{
        char crr = VBI_CPU_RUNRUN;
        char krr = VBI_CPU_KPRUNRUN;
        return crr != 0 || krr != 0;
}

/*
 * This is revision 7 of the interface.
 */

void *
vbi_phys_alloc(uint64_t *phys, size_t size, uint64_t alignment, int contig)
{
        return (vbi_internal_alloc(phys, size, alignment, contig));
}

void
vbi_phys_free(void *va, size_t size)
{
        p_contig_free(va, size);
}


/*
 * This is revision 8 of the interface.
 */
static vnode_t vbipagevp;

page_t **
vbi_pages_alloc(uint64_t *phys, size_t size)
{
        /*
         * the page freelist and cachelist both hold pages that are not mapped into any address space.
         * the cachelist is not really free pages but when memory is exhausted they'll be moved to the
         * free lists.
         * it's the total of the free+cache list that we see on the 'free' column in vmstat.
         */
        page_t **pp_pages = NULL;
        pgcnt_t npages = (size + PAGESIZE - 1) >> PAGESHIFT;

        /* reserve available memory for pages */
        int rc = page_resv(npages, KM_NOSLEEP);
        if (rc)
        {
                /* create the pages */
                rc = page_create_wait(npages, 0 /* flags */);
                if (rc)
                {
                        /* alloc space for page_t pointer array */
                        size_t pp_size = npages * sizeof(page_t *);
                        pp_pages = kmem_zalloc(pp_size, KM_SLEEP);
                        if (pp_pages)
                        {
                                /*
                                 * get pages from kseg, the 'virtAddr' here is only for colouring but unfortunately
                                 * we don't have the 'virtAddr' to which this memory may be mapped.
                                 */
                                caddr_t virtAddr = NULL;
                                for (int64_t i = 0; i < npages; i++, virtAddr += PAGESIZE)
                                {
                                        /* get a page from the freelists */
                                        page_t *ppage = vbi_page_get_fromlist(1 /* freelist */, virtAddr, PAGESIZE);
                                        if (!ppage)
                                        {
                                                /* try from the cachelists */
                                                ppage = vbi_page_get_fromlist(2 /* cachelist */, virtAddr, PAGESIZE);
                                                if (!ppage)
                                                {
                                                        /* damn */
                                                        page_create_putback(npages - i);
                                                        while (--i >= 0)
                                                                page_free(pp_pages[i], 0 /* don't need, move to tail */);
                                                        kmem_free(pp_pages, pp_size);
                                                        page_unresv(npages);
                                                        return NULL;
                                                }

                                                /* remove association with the vnode for pages from the cachelist */
                                                if (!PP_ISAGED(ppage))
                                                        page_hashout(ppage, NULL /* mutex */);
                                        }

                                        PP_CLRFREE(ppage);              /* Page is not free */
                                        PP_CLRAGED(ppage);              /* Page is not hashed in */
                                        pp_pages[i] = ppage;
                                }

                                /*
                                 * we now have the pages locked exclusively, before they are mapped in
                                 * we must downgrade the lock.
                                 */
                                *phys = (uint64_t)page_pptonum(pp_pages[0]) << PAGESHIFT;
                                return pp_pages;
                        }

                        page_create_putback(npages);
                }

                page_unresv(npages);
        }

        return NULL;
}


void
vbi_pages_free(page_t **pp_pages, size_t size)
{
        pgcnt_t npages = (size + PAGESIZE - 1) >> PAGESHIFT;
        size_t pp_size = npages * sizeof(page_t *);
        for (pgcnt_t i = 0; i < npages; i++)
        {
                /* we need to exclusive lock the pages before freeing them */
                int rc = page_tryupgrade(pp_pages[i]);
                if (!rc)
                {
                        page_unlock(pp_pages[i]);
                        while (!page_lock(pp_pages[i], SE_EXCL, NULL /* mutex */, P_RECLAIM))
                                ;
                }

                page_free(pp_pages[i], 0 /* don't need, move to tail */);
        }

        kmem_free(pp_pages, pp_size);
        page_unresv(npages);
}


int
vbi_pages_premap(page_t **pp_pages, size_t size, uint64_t *pphysaddrs)
{
        if (!pphysaddrs)
                return -1;

        pgcnt_t npages = (size + PAGESIZE - 1) >> PAGESHIFT;
        for (pgcnt_t i = 0; i < npages; i++)
        {
                /*
                 * prepare pages for mapping into kernel/user space, we need to
                 * downgrade the exclusive page lock to a shared lock if the
                 * pages is locked exclusively.
                 */
                if (page_tryupgrade(pp_pages[i]) == 1)
                        page_downgrade(pp_pages[i]);
                pphysaddrs[i] = vbi_page_to_pa(pp_pages, i);
        }

        return 0;
}


uint64_t
vbi_page_to_pa(page_t **pp_pages, pgcnt_t i)
{
        pfn_t pfn = page_pptonum(pp_pages[i]);
        if (pfn == PFN_INVALID)
                panic("vbi_page_to_pa: page_pptonum() failed\n");
        return (uint64_t)pfn << PAGESHIFT;
}


static page_t *
vbi_page_get_fromlist(uint_t freelist, caddr_t virtAddr, size_t pgsize)
{
        /* pgsize only applies when using the freelist */
        seg_t kernseg;
        kernseg.s_as = &kas;
        page_t *ppage = NULL;
        if (freelist == 1)
        {
                ppage = page_get_freelist(&vbipagevp, 0 /* offset */, &kernseg, virtAddr,
                                                        pgsize, 0 /* flags */, NULL /* local group */);
                if (!ppage && use_kflt)
                {
                        ppage = page_get_freelist(&vbipagevp, 0 /* offset */, &kernseg, virtAddr,
                                                pgsize, 0x0200 /* PG_KFLT */, NULL /* local group */);
                }
        }
        else
        {
                /* cachelist */
                ppage = page_get_cachelist(&vbipagevp, 0 /* offset */, &kernseg, virtAddr,
                                                        0 /* flags */, NULL /* local group */);
                if (!ppage && use_kflt)
                {
                        ppage = page_get_cachelist(&vbipagevp, 0 /* offset */, &kernseg, virtAddr,
                                                0x0200 /* PG_KFLT */, NULL /* local group */);
                }
        }
        return ppage;
}


/*
 * Large page code.
 */

page_t *
vbi_large_page_alloc(uint64_t *pphys, size_t pgsize)
{
        pgcnt_t const npages = pgsize >> PAGESHIFT;
        page_t *pproot, *pp, *pplist;
        pgcnt_t ipage;
        caddr_t vaddr;
        seg_t kernseg;
        int rc;

        /*
         * Reserve available memory for a large page and create it.
         */
        rc = page_resv(npages, KM_NOSLEEP);
        if (!rc)
                return NULL;

        rc = page_create_wait(npages, 0 /* flags */);
        if (!rc) {
                page_unresv(npages);
                return NULL;
        }

        /*
         * Get a page off the free list.  We set vaddr to 0 since we don't know
         * where the memory is going to be mapped.
         */
        vaddr = NULL;
        kernseg.s_as = &kas;
        pproot = vbi_page_get_fromlist(1 /* freelist */, vaddr, pgsize);
        if (!pproot)
        {
                page_create_putback(npages);
                page_unresv(npages);
                return NULL;
        }
        AssertMsg(!(page_pptonum(pproot) & (npages - 1)), ("%p:%lx npages=%lx\n", pproot, page_pptonum(pproot), npages));

        /*
         * Mark all the sub-pages as non-free and not-hashed-in.
         * It is paramount that we destroy the list (before freeing it).
         */
        pplist = pproot;
        for (ipage = 0; ipage < npages; ipage++) {
                pp = pplist;
                AssertPtr(pp);
                AssertMsg(page_pptonum(pp) == ipage + page_pptonum(pproot),
                        ("%p:%lx %lx+%lx\n", pp, page_pptonum(pp), ipage, page_pptonum(pproot)));
                page_sub(&pplist, pp);
                AssertMsg(PP_ISFREE(pp), ("%p\n", pp));
                AssertMsg(pp->p_szc == pproot->p_szc, ("%p - %d expected %d \n", pp, pp->p_szc, pproot->p_szc));

                PP_CLRFREE(pp);
                PP_CLRAGED(pp);
        }

        *pphys = (uint64_t)page_pptonum(pproot) << PAGESHIFT;
        AssertMsg(!(*pphys & (pgsize - 1)), ("%llx %zx\n", *pphys, pgsize));
        return pproot;
}

void
vbi_large_page_free(page_t *pproot, size_t pgsize)
{
        pgcnt_t const npages = pgsize >> PAGESHIFT;
        pgcnt_t ipage;

        Assert(page_get_pagecnt(pproot->p_szc) == npages);
        AssertMsg(!(page_pptonum(pproot) & (npages - 1)), ("%p:%lx npages=%lx\n", pproot, page_pptonum(pproot), npages));

        /*
         * We need to exclusively lock the sub-pages before freeing
         * the large one.
         */
        for (ipage = 0; ipage < npages; ipage++) {
                page_t *pp = page_nextn(pproot, ipage);
                AssertMsg(page_pptonum(pp) == ipage + page_pptonum(pproot),
                        ("%p:%lx %lx+%lx\n", pp, page_pptonum(pp), ipage, page_pptonum(pproot)));
                AssertMsg(!PP_ISFREE(pp), ("%p\n", pp));

                int rc = page_tryupgrade(pp);
                if (!rc) {
                        page_unlock(pp);
                        while (!page_lock(pp, SE_EXCL, NULL /* mutex */, P_RECLAIM)) {
                                /*nothing*/;
                        }
                }
        }

        /*
         * Free the large page and unreserve the memory.
         */
        page_free_pages(pproot);
        page_unresv(npages);
}

int
vbi_large_page_premap(page_t *pproot, size_t pgsize)
{
        pgcnt_t const npages = pgsize >> PAGESHIFT;
        pgcnt_t ipage;

        Assert(page_get_pagecnt(pproot->p_szc) == npages);
        AssertMsg(!(page_pptonum(pproot) & (npages - 1)), ("%p:%lx npages=%lx\n", pproot, page_pptonum(pproot), npages));

        /*
         * We need to downgrade the sub-pages from exclusive to shared locking
         * because otherwise we cannot <you go figure>.
         */
        for (ipage = 0; ipage < npages; ipage++) {
            page_t *pp = page_nextn(pproot, ipage);
            AssertMsg(page_pptonum(pp) == ipage + page_pptonum(pproot),
                    ("%p:%lx %lx+%lx\n", pp, page_pptonum(pp), ipage, page_pptonum(pproot)));
            AssertMsg(!PP_ISFREE(pp), ("%p\n", pp));

            if (page_tryupgrade(pp) == 1)
                    page_downgrade(pp);
            AssertMsg(!PP_ISFREE(pp), ("%p\n", pp));
        }

        return 0;
}


/*
 * As more functions are added, they should start with a comment indicating
 * the revision and above this point in the file and the revision level should
 * be increased. Also change vbi_modlmisc at the top of the file.
 *
 * NOTE! We'll start care about this if anything in here ever makes it into
 *       the solaris kernel proper.
 */
uint_t vbi_revision_level = 9;