xnu-1504.7.4.tar.gz

[apple/xnu.git] / osfmk / i386 / loose_ends.c

/*
 * Copyright (c) 2000-2008 Apple Inc. All rights reserved.
 *
 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
 * 
 * This file contains Original Code and/or Modifications of Original Code
 * as defined in and that are subject to the Apple Public Source License
 * Version 2.0 (the 'License'). You may not use this file except in
 * compliance with the License. The rights granted to you under the License
 * may not be used to create, or enable the creation or redistribution of,
 * unlawful or unlicensed copies of an Apple operating system, or to
 * circumvent, violate, or enable the circumvention or violation of, any
 * terms of an Apple operating system software license agreement.
 * 
 * Please obtain a copy of the License at
 * http://www.opensource.apple.com/apsl/ and read it before using this file.
 * 
 * The Original Code and all software distributed under the License are
 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
 * Please see the License for the specific language governing rights and
 * limitations under the License.
 * 
 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
 */
/*
 * @OSF_COPYRIGHT@
 */
/* 
 * Mach Operating System
 * Copyright (c) 1991,1990,1989 Carnegie Mellon University
 * All Rights Reserved.
 * 
 * Permission to use, copy, modify and distribute this software and its
 * documentation is hereby granted, provided that both the copyright
 * notice and this permission notice appear in all copies of the
 * software, derivative works or modified versions, and any portions
 * thereof, and that both notices appear in supporting documentation.
 * 
 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
 * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
 * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
 * 
 * Carnegie Mellon requests users of this software to return to
 * 
 *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
 *  School of Computer Science
 *  Carnegie Mellon University
 *  Pittsburgh PA 15213-3890
 * 
 * any improvements or extensions that they make and grant Carnegie Mellon
 * the rights to redistribute these changes.
 */
/*
 */
#include <mach_assert.h>

#include <string.h>
#include <mach/boolean.h>
#include <mach/i386/vm_types.h>
#include <mach/i386/vm_param.h>
#include <kern/kern_types.h>
#include <kern/misc_protos.h>
#include <sys/errno.h>
#include <i386/param.h>
#include <i386/misc_protos.h>
#include <i386/cpu_data.h>
#include <i386/machine_routines.h>
#include <i386/cpuid.h>
#include <i386/vmx.h>
#include <vm/pmap.h>
#include <vm/vm_map.h>
#include <vm/vm_kern.h>
#include <vm/vm_fault.h>

#include <libkern/OSAtomic.h>
#include <sys/kdebug.h>


#if 0

#undef KERNEL_DEBUG
#define KERNEL_DEBUG KERNEL_DEBUG_CONSTANT
#define KDEBUG 1

#endif

/* XXX - should be gone from here */
extern void             invalidate_icache64(addr64_t addr, unsigned cnt, int phys);
extern void             flush_dcache64(addr64_t addr, unsigned count, int phys);
extern boolean_t        phys_page_exists(ppnum_t);
extern void             bcopy_no_overwrite(const char *from, char *to,vm_size_t bytes);
extern void             pmap_set_reference(ppnum_t pn);
extern void             mapping_set_mod(ppnum_t pa); 
extern void             mapping_set_ref(ppnum_t pn);

extern void             ovbcopy(const char      *from,
                                char            *to,
                                vm_size_t       nbytes);
void machine_callstack(natural_t *buf, vm_size_t callstack_max);


#define value_64bit(value)  ((value) & 0xFFFFFFFF00000000LL)
#define low32(x)  ((unsigned int)((x) & 0x00000000FFFFFFFFLL))




void
bzero_phys_nc(
              addr64_t src64,
              uint32_t bytes)
{
  bzero_phys(src64,bytes);
}

void
bzero_phys(
           addr64_t src64,
           uint32_t bytes)
{
        mapwindow_t *map;

        mp_disable_preemption();

        map = pmap_get_mapwindow((pt_entry_t)(INTEL_PTE_VALID | INTEL_PTE_RW | ((pmap_paddr_t)src64 & PG_FRAME) | INTEL_PTE_REF | INTEL_PTE_MOD));

        bzero((void *)((uintptr_t)map->prv_CADDR | ((uint32_t)src64 & INTEL_OFFMASK)), bytes);

        pmap_put_mapwindow(map);

        mp_enable_preemption();
}


/*
 * bcopy_phys - like bcopy but copies from/to physical addresses.
 */

void
bcopy_phys(
           addr64_t src64,
           addr64_t dst64,
           vm_size_t bytes)
{
        mapwindow_t *src_map, *dst_map;

        /* ensure we stay within a page */
        if ( ((((uint32_t)src64 & (NBPG-1)) + bytes) > NBPG) || ((((uint32_t)dst64 & (NBPG-1)) + bytes) > NBPG) ) {
                panic("bcopy_phys alignment");
        }
        mp_disable_preemption();

        src_map = pmap_get_mapwindow((pt_entry_t)(INTEL_PTE_VALID | ((pmap_paddr_t)src64 & PG_FRAME) | INTEL_PTE_REF));
        dst_map = pmap_get_mapwindow((pt_entry_t)(INTEL_PTE_VALID | INTEL_PTE_RW | ((pmap_paddr_t)dst64 & PG_FRAME) |
                                                  INTEL_PTE_REF | INTEL_PTE_MOD));

        bcopy((void *) ((uintptr_t)src_map->prv_CADDR | ((uint32_t)src64 & INTEL_OFFMASK)),
              (void *) ((uintptr_t)dst_map->prv_CADDR | ((uint32_t)dst64 & INTEL_OFFMASK)), bytes);

        pmap_put_mapwindow(src_map);
        pmap_put_mapwindow(dst_map);

        mp_enable_preemption();
}

/* 
 * ovbcopy - like bcopy, but recognizes overlapping ranges and handles 
 *           them correctly.
 */

void
ovbcopy(
        const char      *from,
        char            *to,
        vm_size_t       bytes)          /* num bytes to copy */
{
        /* Assume that bcopy copies left-to-right (low addr first). */
        if (from + bytes <= to || to + bytes <= from || to == from)
                bcopy_no_overwrite(from, to, bytes);    /* non-overlapping or no-op*/
        else if (from > to)
                bcopy_no_overwrite(from, to, bytes);    /* overlapping but OK */
        else {
                /* to > from: overlapping, and must copy right-to-left. */
                from += bytes - 1;
                to += bytes - 1;
                while (bytes-- > 0)
                        *to-- = *from--;
        }
}


/*
 *  Read data from a physical address.
 */


static unsigned int
ml_phys_read_data(pmap_paddr_t paddr, int size )
{
        mapwindow_t *map;
        unsigned int result;

        mp_disable_preemption();

        map = pmap_get_mapwindow((pt_entry_t)(INTEL_PTE_VALID | (paddr & PG_FRAME) | INTEL_PTE_REF));

        switch (size) {
            unsigned char s1;
            unsigned short s2;
        case 1:
            s1 = *(unsigned char *)((uintptr_t)map->prv_CADDR | ((uint32_t)paddr & INTEL_OFFMASK));
            result = s1;
            break;
        case 2:
            s2 = *(unsigned short *)((uintptr_t)map->prv_CADDR | ((uint32_t)paddr & INTEL_OFFMASK));
            result = s2;
            break;
        case 4:
        default:
            result = *(unsigned int *)((uintptr_t)map->prv_CADDR | ((uint32_t)paddr & INTEL_OFFMASK));
            break;
        }
        pmap_put_mapwindow(map);

        mp_enable_preemption();

        return result;
}

static unsigned long long
ml_phys_read_long_long(pmap_paddr_t paddr )
{
        mapwindow_t *map;
        unsigned long long result;

        mp_disable_preemption();

        map = pmap_get_mapwindow((pt_entry_t)(INTEL_PTE_VALID | (paddr & PG_FRAME) | INTEL_PTE_REF));

        result = *(unsigned long long *)((uintptr_t)map->prv_CADDR | ((uint32_t)paddr & INTEL_OFFMASK));

        pmap_put_mapwindow(map);

        mp_enable_preemption();

        return result;
}

unsigned int ml_phys_read( vm_offset_t paddr)
{
        return ml_phys_read_data((pmap_paddr_t)paddr, 4);
}

unsigned int ml_phys_read_word(vm_offset_t paddr) {

        return ml_phys_read_data((pmap_paddr_t)paddr, 4);
}

unsigned int ml_phys_read_64(addr64_t paddr64)
{
        return ml_phys_read_data((pmap_paddr_t)paddr64, 4);
}

unsigned int ml_phys_read_word_64(addr64_t paddr64)
{
        return ml_phys_read_data((pmap_paddr_t)paddr64, 4);
}

unsigned int ml_phys_read_half(vm_offset_t paddr)
{
        return ml_phys_read_data((pmap_paddr_t)paddr, 2);
}

unsigned int ml_phys_read_half_64(addr64_t paddr64)
{
        return ml_phys_read_data((pmap_paddr_t)paddr64, 2);
}

unsigned int ml_phys_read_byte(vm_offset_t paddr)
{
        return ml_phys_read_data((pmap_paddr_t)paddr, 1);
}

unsigned int ml_phys_read_byte_64(addr64_t paddr64)
{
        return ml_phys_read_data((pmap_paddr_t)paddr64, 1);
}

unsigned long long ml_phys_read_double(vm_offset_t paddr)
{
        return ml_phys_read_long_long((pmap_paddr_t)paddr);
}

unsigned long long ml_phys_read_double_64(addr64_t paddr64)
{
        return ml_phys_read_long_long((pmap_paddr_t)paddr64);
}



/*
 *  Write data to a physical address.
 */

static void
ml_phys_write_data(pmap_paddr_t paddr, unsigned long data, int size)
{
        mapwindow_t *map;

        mp_disable_preemption();

        map = pmap_get_mapwindow((pt_entry_t)(INTEL_PTE_VALID | INTEL_PTE_RW | (paddr & PG_FRAME) | 
                                          INTEL_PTE_REF | INTEL_PTE_MOD));

        switch (size) {
        case 1:
            *(unsigned char *)((uintptr_t)map->prv_CADDR | ((uint32_t)paddr & INTEL_OFFMASK)) = (unsigned char)data;
            break;
        case 2:
            *(unsigned short *)((uintptr_t)map->prv_CADDR | ((uint32_t)paddr & INTEL_OFFMASK)) = (unsigned short)data;
            break;
        case 4:
        default:
            *(unsigned int *)((uintptr_t)map->prv_CADDR | ((uint32_t)paddr & INTEL_OFFMASK)) = data;
            break;
        }
        pmap_put_mapwindow(map);

        mp_enable_preemption();
}

static void
ml_phys_write_long_long(pmap_paddr_t paddr, unsigned long long data)
{
        mapwindow_t *map;

        mp_disable_preemption();

        map = pmap_get_mapwindow((pt_entry_t)(INTEL_PTE_VALID | INTEL_PTE_RW | (paddr & PG_FRAME) | 
                                              INTEL_PTE_REF | INTEL_PTE_MOD));

        *(unsigned long long *)((uintptr_t)map->prv_CADDR | ((uint32_t)paddr & INTEL_OFFMASK)) = data;

        pmap_put_mapwindow(map);

        mp_enable_preemption();
}



void ml_phys_write_byte(vm_offset_t paddr, unsigned int data)
{
        ml_phys_write_data((pmap_paddr_t)paddr, data, 1);
}

void ml_phys_write_byte_64(addr64_t paddr64, unsigned int data)
{
        ml_phys_write_data((pmap_paddr_t)paddr64, data, 1);
}

void ml_phys_write_half(vm_offset_t paddr, unsigned int data)
{
        ml_phys_write_data((pmap_paddr_t)paddr, data, 2);
}

void ml_phys_write_half_64(addr64_t paddr64, unsigned int data)
{
        ml_phys_write_data((pmap_paddr_t)paddr64, data, 2);
}

void ml_phys_write(vm_offset_t paddr, unsigned int data)
{
        ml_phys_write_data((pmap_paddr_t)paddr, data, 4);
}

void ml_phys_write_64(addr64_t paddr64, unsigned int data)
{
        ml_phys_write_data((pmap_paddr_t)paddr64, data, 4);
}

void ml_phys_write_word(vm_offset_t paddr, unsigned int data)
{
        ml_phys_write_data((pmap_paddr_t)paddr, data, 4);
}

void ml_phys_write_word_64(addr64_t paddr64, unsigned int data)
{
        ml_phys_write_data((pmap_paddr_t)paddr64, data, 4);
}

void ml_phys_write_double(vm_offset_t paddr, unsigned long long data)
{
        ml_phys_write_long_long((pmap_paddr_t)paddr, data);
}

void ml_phys_write_double_64(addr64_t paddr64, unsigned long long data)
{
        ml_phys_write_long_long((pmap_paddr_t)paddr64, data);
}


/* PCI config cycle probing
 *
 *
 *      Read the memory location at physical address paddr.
 *  This is a part of a device probe, so there is a good chance we will
 *  have a machine check here. So we have to be able to handle that.
 *  We assume that machine checks are enabled both in MSR and HIDs
 */

boolean_t
ml_probe_read(vm_offset_t paddr, unsigned int *val)
{
    if ((PAGE_SIZE - (paddr & PAGE_MASK)) < 4)
        return FALSE;

    *val = ml_phys_read(paddr);

    return TRUE;
}

/*
 *  Read the memory location at physical address paddr.
 *  This is a part of a device probe, so there is a good chance we will
 *  have a machine check here. So we have to be able to handle that.
 *  We assume that machine checks are enabled both in MSR and HIDs
 */
boolean_t 
ml_probe_read_64(addr64_t paddr64, unsigned int *val)
{
    if ((PAGE_SIZE - (paddr64 & PAGE_MASK)) < 4)
        return FALSE;

    *val = ml_phys_read_64((pmap_paddr_t)paddr64);
    return TRUE;
}


int bcmp(
        const void      *pa,
        const void      *pb,
        size_t  len)
{
        const char *a = (const char *)pa;
        const char *b = (const char *)pb;

        if (len == 0)
                return 0;

        do
                if (*a++ != *b++)
                        break;
        while (--len);

        return len;
}

int
memcmp(const void *s1, const void *s2, size_t n)
{
        if (n != 0) {
                const unsigned char *p1 = s1, *p2 = s2;

                do {
                        if (*p1++ != *p2++)
                                return (*--p1 - *--p2);
                } while (--n != 0);
        }
        return (0);
}

/*
 * Abstract:
 * strlen returns the number of characters in "string" preceeding
 * the terminating null character.
 */

size_t
strlen(
        register const char *string)
{
        register const char *ret = string;

        while (*string++ != '\0')
                continue;
        return string - 1 - ret;
}

uint32_t
hw_compare_and_store(uint32_t oldval, uint32_t newval, volatile uint32_t *dest)
{
        return OSCompareAndSwap((UInt32)oldval,
                                (UInt32)newval,
                                (volatile UInt32 *)dest);
}

#if     MACH_ASSERT

/*
 * Machine-dependent routine to fill in an array with up to callstack_max
 * levels of return pc information.
 */
void machine_callstack(
        __unused natural_t      *buf,
        __unused vm_size_t      callstack_max)
{
}

#endif  /* MACH_ASSERT */

void fillPage(ppnum_t pa, unsigned int fill)
{
        mapwindow_t *map;
        pmap_paddr_t src;
        int i;
        int cnt = PAGE_SIZE/sizeof(unsigned int);
        unsigned int *addr;

        mp_disable_preemption();

        src = i386_ptob(pa);
        map = pmap_get_mapwindow((pt_entry_t)(INTEL_PTE_VALID | INTEL_PTE_RW | (src & PG_FRAME) | 
                                              INTEL_PTE_REF | INTEL_PTE_MOD));

        for (i = 0, addr = (unsigned int *)map->prv_CADDR; i < cnt ; i++ )
                *addr++ = fill;

        pmap_put_mapwindow(map);

        mp_enable_preemption();
}

static inline void __sfence(void)
{
    __asm__ volatile("sfence");
}
static inline void __mfence(void)
{
    __asm__ volatile("mfence");
}
static inline void __wbinvd(void)
{
    __asm__ volatile("wbinvd");
}
static inline void __clflush(void *ptr)
{
        __asm__ volatile("clflush (%0)" : : "r" (ptr));
}

void dcache_incoherent_io_store64(addr64_t pa, unsigned int count)
{
        mapwindow_t *map;
        uint32_t  linesize = cpuid_info()->cache_linesize;
        addr64_t  addr;
        uint32_t  offset, chunk;
        boolean_t istate;

        __mfence();

        istate = ml_set_interrupts_enabled(FALSE);

        offset = (uint32_t)(pa & (linesize - 1));
        addr   = pa - offset;

        map = pmap_get_mapwindow((pt_entry_t)(i386_ptob(atop_64(addr)) | INTEL_PTE_VALID));

        count += offset;
        offset = (uint32_t)(addr & ((addr64_t) (page_size - 1)));
        chunk  = page_size - offset;

        do
        {
            if (chunk > count)
                chunk = count;
    
            for (; offset < chunk; offset += linesize)
                __clflush((void *)(((uintptr_t)map->prv_CADDR) + offset));

            count -= chunk;
            addr  += chunk;
            chunk  = page_size;
            offset = 0;

            if (count) {
                pmap_store_pte(map->prv_CMAP, (pt_entry_t)(i386_ptob(atop_64(addr)) | INTEL_PTE_VALID));
                invlpg((uintptr_t)map->prv_CADDR);
            }
        }
        while (count);

        pmap_put_mapwindow(map);

        (void) ml_set_interrupts_enabled(istate);

        __mfence();
}

void dcache_incoherent_io_flush64(addr64_t pa, unsigned int count)
{
    return(dcache_incoherent_io_store64(pa,count));
}

void
flush_dcache64(__unused addr64_t addr,
               __unused unsigned count,
               __unused int phys)
{
}

void
invalidate_icache64(__unused addr64_t addr,
                    __unused unsigned count,
                    __unused int phys)
{
}


addr64_t         vm_last_addr;

void
mapping_set_mod(ppnum_t pn)
{
  pmap_set_modify(pn);
}

void
mapping_set_ref(ppnum_t pn)
{
  pmap_set_reference(pn);
}

void
cache_flush_page_phys(ppnum_t pa)
{
        mapwindow_t     *map;
        boolean_t       istate;
        int             i;
        unsigned char   *cacheline_addr;
        int             cacheline_size = cpuid_info()->cache_linesize;
        int             cachelines_in_page = PAGE_SIZE/cacheline_size;

        __mfence();

        istate = ml_set_interrupts_enabled(FALSE);

        map = pmap_get_mapwindow((pt_entry_t)(i386_ptob(pa) | INTEL_PTE_VALID));

        for (i = 0, cacheline_addr = (unsigned char *)map->prv_CADDR;
             i < cachelines_in_page;
             i++, cacheline_addr += cacheline_size) {
                __clflush((void *) cacheline_addr);
        }
        pmap_put_mapwindow(map);

        (void) ml_set_interrupts_enabled(istate);

        __mfence();
}


/*
 * the copy engine has the following characteristics
 *   - copyio handles copies to/from user or kernel space
 *   - copypv deals with physical or virtual addresses
 *
 * implementation details as follows
 *   - a cache of up to NCOPY_WINDOWS is maintained per thread for
 *     access of user virutal space
 *   - the window size is determined by the amount of virtual space
 *     that can be mapped by a single page table
 *   - the mapping is done by copying the page table pointer from
 *     the user's directory entry corresponding to the window's
 *     address in user space to the directory entry corresponding
 *     to the window slot in the kernel's address space
 *   - the set of mappings is preserved across context switches,
 *     so the copy can run with pre-emption enabled
 *   - there is a gdt entry set up to anchor the kernel window on
 *     each processor
 *   - the copies are done using the selector corresponding to the
 *     gdt entry
 *   - the addresses corresponding to the user virtual address are
 *     relative to the beginning of the window being used to map
 *     that region... thus the thread can be pre-empted and switched
 *     to a different processor while in the midst of a copy
 *   - the window caches must be invalidated if the pmap changes out
 *     from under the thread... this can happen during vfork/exec...
 *     inval_copy_windows is the invalidation routine to be used
 *   - the copyio engine has 4 different states associated with it
 *     that allows for lazy tlb flushes and the ability to avoid
 *     a flush all together if we've just come from user space
 *     the 4 states are as follows...
 *
 *      WINDOWS_OPENED - set by copyio to indicate to the context
 *        switch code that it is necessary to do a tlbflush after
 *        switching the windows since we're in the middle of a copy
 *
 *      WINDOWS_CLOSED - set by copyio to indicate that it's done
 *        using the windows, so that the context switch code need
 *        not do the tlbflush... instead it will set the state to...
 *
 *      WINDOWS_DIRTY - set by the context switch code to indicate
 *        to the copy engine that it is responsible for doing a 
 *        tlbflush before using the windows again... it's also
 *        set by the inval_copy_windows routine to indicate the
 *        same responsibility.
 *
 *      WINDOWS_CLEAN - set by the return to user path to indicate
 *        that a tlbflush has happened and that there is no need
 *        for copyio to do another when it is entered next...
 *
 *   - a window for mapping single physical pages is provided for copypv
 *   - this window is maintained across context switches and has the
 *     same characteristics as the user space windows w/r to pre-emption
 */

extern int copyout_user(const char *, vm_offset_t, vm_size_t);
extern int copyout_kern(const char *, vm_offset_t, vm_size_t);
extern int copyin_user(const vm_offset_t, char *, vm_size_t);
extern int copyin_kern(const vm_offset_t, char *, vm_size_t);
extern int copyoutphys_user(const char *, vm_offset_t, vm_size_t);
extern int copyoutphys_kern(const char *, vm_offset_t, vm_size_t);
extern int copyinphys_user(const vm_offset_t, char *, vm_size_t);
extern int copyinphys_kern(const vm_offset_t, char *, vm_size_t);
extern int copyinstr_user(const vm_offset_t, char *, vm_size_t, vm_size_t *);
extern int copyinstr_kern(const vm_offset_t, char *, vm_size_t, vm_size_t *);

static int copyio(int, user_addr_t, char *, vm_size_t, vm_size_t *, int);
static int copyio_phys(addr64_t, addr64_t, vm_size_t, int);


#define COPYIN          0
#define COPYOUT         1
#define COPYINSTR       2
#define COPYINPHYS      3
#define COPYOUTPHYS     4


void inval_copy_windows(thread_t thread)
{
        int     i;
        
        for (i = 0; i < NCOPY_WINDOWS; i++) {
                thread->machine.copy_window[i].user_base = -1;
        }
        thread->machine.nxt_window = 0;
        thread->machine.copyio_state = WINDOWS_DIRTY;

        KERNEL_DEBUG(0xeff70058 | DBG_FUNC_NONE, (uintptr_t)thread_tid(thread), (int)thread->map, 0, 0, 0);
}


static int
copyio(int copy_type, user_addr_t user_addr, char *kernel_addr,
       vm_size_t nbytes, vm_size_t *lencopied, int use_kernel_map)
{
        thread_t        thread;
        pmap_t          pmap;
        pt_entry_t      *updp;
        pt_entry_t      *kpdp;
        user_addr_t     user_base;
        vm_offset_t     user_offset;
        vm_offset_t     kern_vaddr;
        vm_size_t       cnt;
        vm_size_t       bytes_copied;
        int             error = 0;
        int             window_index;
        int             copyio_state;
        boolean_t       istate;
#if KDEBUG
        int             debug_type = 0xeff70010;
        debug_type += (copy_type << 2);
#endif

        thread = current_thread();

        KERNEL_DEBUG(debug_type | DBG_FUNC_START, (int)(user_addr >> 32), (int)user_addr,
                     (int)nbytes, thread->machine.copyio_state, 0);

        if (nbytes == 0) {
                KERNEL_DEBUG(debug_type | DBG_FUNC_END, (unsigned)user_addr,
                             (unsigned)kernel_addr, (unsigned)nbytes, 0, 0);
                return (0);
        }
        pmap = thread->map->pmap;

        if (pmap == kernel_pmap || use_kernel_map) {

                kern_vaddr = (vm_offset_t)user_addr;
          
                switch (copy_type) {

                case COPYIN:
                        error = copyin_kern(kern_vaddr, kernel_addr, nbytes);
                        break;

                case COPYOUT:
                        error = copyout_kern(kernel_addr, kern_vaddr, nbytes);
                        break;

                case COPYINSTR:
                        error = copyinstr_kern(kern_vaddr, kernel_addr, nbytes, lencopied);
                        break;

                case COPYINPHYS:
                        error = copyinphys_kern(kern_vaddr, kernel_addr, nbytes);
                        break;

                case COPYOUTPHYS:
                        error = copyoutphys_kern(kernel_addr, kern_vaddr, nbytes);
                        break;
                }
                KERNEL_DEBUG(debug_type | DBG_FUNC_END, (unsigned)kern_vaddr,
                             (unsigned)kernel_addr, (unsigned)nbytes,
                             error | 0x80000000, 0);
                return (error);
        }

#if CONFIG_DTRACE
        thread->machine.specFlags |= CopyIOActive;
#endif /* CONFIG_DTRACE */

        if ((nbytes && (user_addr + nbytes <= user_addr)) || ((user_addr + nbytes) > vm_map_max(thread->map))) {
                error = EFAULT;
                goto done;
        }

        user_base = user_addr & ~((user_addr_t)(NBPDE - 1));
        user_offset = (vm_offset_t)(user_addr & (NBPDE - 1));

        KERNEL_DEBUG(debug_type | DBG_FUNC_NONE, (int)(user_base >> 32), (int)user_base,
                     (int)user_offset, 0, 0);

        cnt = NBPDE - user_offset;

        if (cnt > nbytes)
                cnt = nbytes;

        istate = ml_set_interrupts_enabled(FALSE);

        copyio_state = thread->machine.copyio_state;
        thread->machine.copyio_state = WINDOWS_OPENED;

        (void) ml_set_interrupts_enabled(istate);


        for (;;) {

                for (window_index = 0; window_index < NCOPY_WINDOWS; window_index++) {
                        if (thread->machine.copy_window[window_index].user_base == user_base)
                                break;
                }
                if (window_index >= NCOPY_WINDOWS) {

                        window_index = thread->machine.nxt_window;
                        thread->machine.nxt_window++;

                        if (thread->machine.nxt_window >= NCOPY_WINDOWS)
                                thread->machine.nxt_window = 0;
                        thread->machine.copy_window[window_index].user_base = user_base;

                        /*
                         * it's necessary to disable pre-emption
                         * since I have to compute the kernel descriptor pointer
                         * for the new window
                         */
                        istate = ml_set_interrupts_enabled(FALSE);

                        updp = pmap_pde(pmap, user_base);

                        kpdp = current_cpu_datap()->cpu_copywindow_pdp;
                        kpdp += window_index;

                        pmap_store_pte(kpdp, updp ? *updp : 0);

                        (void) ml_set_interrupts_enabled(istate);

                        copyio_state = WINDOWS_DIRTY;

                        KERNEL_DEBUG(0xeff70040 | DBG_FUNC_NONE, window_index,
                                     (unsigned)user_base, (unsigned)updp,
                                     (unsigned)kpdp, 0);

                }
#if JOE_DEBUG
                else {
                        istate = ml_set_interrupts_enabled(FALSE);

                        updp = pmap_pde(pmap, user_base);

                        kpdp = current_cpu_datap()->cpu_copywindow_pdp;

                        kpdp += window_index;

                        if ((*kpdp & PG_FRAME) != (*updp & PG_FRAME)) {
                                panic("copyio: user pdp mismatch - kpdp = 0x%qx,  updp = 0x%qx\n", *kpdp, *updp);
                        }
                        (void) ml_set_interrupts_enabled(istate);
                }
#endif
                if (copyio_state == WINDOWS_DIRTY) {
                        flush_tlb();

                        copyio_state = WINDOWS_CLEAN;

                        KERNEL_DEBUG(0xeff70054 | DBG_FUNC_NONE, window_index, 0, 0, 0, 0);
                }
                user_offset += (window_index * NBPDE);

                KERNEL_DEBUG(0xeff70044 | DBG_FUNC_NONE, (unsigned)user_offset,
                             (unsigned)kernel_addr, cnt, 0, 0);

                switch (copy_type) {

                case COPYIN:
                        error = copyin_user(user_offset, kernel_addr, cnt);
                        break;
                        
                case COPYOUT:
                        error = copyout_user(kernel_addr, user_offset, cnt);
                        break;

                case COPYINPHYS:
                        error = copyinphys_user(user_offset, kernel_addr, cnt);
                        break;
                        
                case COPYOUTPHYS:
                        error = copyoutphys_user(kernel_addr, user_offset, cnt);
                        break;

                case COPYINSTR:
                        error = copyinstr_user(user_offset, kernel_addr, cnt, &bytes_copied);

                        /*
                         * lencopied should be updated on success
                         * or ENAMETOOLONG...  but not EFAULT
                         */
                        if (error != EFAULT)
                                *lencopied += bytes_copied;

                        /*
                         * if we still have room, then the ENAMETOOLONG
                         * is just an artifact of the buffer straddling
                         * a window boundary and we should continue
                         */
                        if (error == ENAMETOOLONG && nbytes > cnt)
                                error = 0;

                        if (error) {
#if KDEBUG
                                nbytes = *lencopied;
#endif
                                break;
                        }
                        if (*(kernel_addr + bytes_copied - 1) == 0) {
                                /*
                                 * we found a NULL terminator... we're done
                                 */
#if KDEBUG
                                nbytes = *lencopied;
#endif
                                goto done;
                        }
                        if (cnt == nbytes) {
                                /*
                                 * no more room in the buffer and we haven't
                                 * yet come across a NULL terminator
                                 */
#if KDEBUG
                                nbytes = *lencopied;
#endif
                                error = ENAMETOOLONG;
                                break;
                        }
                        assert(cnt == bytes_copied);

                        break;
                }
                if (error)
                        break;
                if ((nbytes -= cnt) == 0)
                        break;

                kernel_addr += cnt;
                user_base += NBPDE;
                user_offset = 0;

                if (nbytes > NBPDE)
                        cnt = NBPDE;
                else
                        cnt = nbytes;
        }
done:
        thread->machine.copyio_state = WINDOWS_CLOSED;

        KERNEL_DEBUG(debug_type | DBG_FUNC_END, (unsigned)user_addr,
                     (unsigned)kernel_addr, (unsigned)nbytes, error, 0);

#if CONFIG_DTRACE
        thread->machine.specFlags &= ~CopyIOActive;
#endif /* CONFIG_DTRACE */

        return (error);
}


static int
copyio_phys(addr64_t source, addr64_t sink, vm_size_t csize, int which)
{
        pmap_paddr_t paddr;
        user_addr_t vaddr;
        char        *window_offset;
        pt_entry_t  pentry;
        int         ctype;
        int         retval;
        boolean_t   istate;

        if (which & cppvPsnk) {
                paddr  = (pmap_paddr_t)sink;
                vaddr  = (user_addr_t)source;
                ctype  = COPYINPHYS;
                pentry = (pt_entry_t)(INTEL_PTE_VALID | (paddr & PG_FRAME) | INTEL_PTE_RW);
        } else {
                paddr  = (pmap_paddr_t)source;
                vaddr  = (user_addr_t)sink;
                ctype  = COPYOUTPHYS;
                pentry = (pt_entry_t)(INTEL_PTE_VALID | (paddr & PG_FRAME));
        }
        window_offset = (char *)((uint32_t)paddr & (PAGE_SIZE - 1));

        assert(!((current_thread()->machine.specFlags & CopyIOActive) && ((which & cppvKmap) == 0)));

        if (current_thread()->machine.physwindow_busy) {
                pt_entry_t      old_pentry;

                KERNEL_DEBUG(0xeff70048 | DBG_FUNC_NONE, paddr, csize, 0, -1, 0);
                /*
                 * we had better be targeting wired memory at this point
                 * we will not be able to handle a fault with interrupts
                 * disabled... we disable them because we can't tolerate
                 * being preempted during this nested use of the window
                 */
                istate = ml_set_interrupts_enabled(FALSE);

                old_pentry = *(current_cpu_datap()->cpu_physwindow_ptep);
                pmap_store_pte((current_cpu_datap()->cpu_physwindow_ptep), pentry);

                invlpg((uintptr_t)current_cpu_datap()->cpu_physwindow_base);

                retval = copyio(ctype, vaddr, window_offset, csize, NULL, which & cppvKmap);

                pmap_store_pte((current_cpu_datap()->cpu_physwindow_ptep), old_pentry);

                invlpg((uintptr_t)current_cpu_datap()->cpu_physwindow_base);

                (void) ml_set_interrupts_enabled(istate);
        } else {
                /*
                 * mark the window as in use... if an interrupt hits while we're
                 * busy, or we trigger another coyppv from the fault path into
                 * the driver on a user address space page fault due to a copyin/out
                 * then we need to save and restore the current window state instead
                 * of caching the window preserving it across context switches
                 */
                current_thread()->machine.physwindow_busy = 1;

                if (current_thread()->machine.physwindow_pte != pentry) {
                        KERNEL_DEBUG(0xeff70048 | DBG_FUNC_NONE, paddr, csize, 0, 0, 0);

                        current_thread()->machine.physwindow_pte = pentry;
                        
                        /*
                         * preemption at this point would be bad since we
                         * could end up on the other processor after we grabbed the
                         * pointer to the current cpu data area, but before we finished
                         * using it to stuff the page table entry since we would
                         * be modifying a window that no longer belonged to us
                         * the invlpg can be done unprotected since it only flushes
                         * this page address from the tlb... if it flushes the wrong
                         * one, no harm is done, and the context switch that moved us
                         * to the other processor will have already take care of 
                         * flushing the tlb after it reloaded the page table from machine.physwindow_pte
                         */
                        istate = ml_set_interrupts_enabled(FALSE);

                        pmap_store_pte((current_cpu_datap()->cpu_physwindow_ptep), pentry);
                        (void) ml_set_interrupts_enabled(istate);

                        invlpg((uintptr_t)current_cpu_datap()->cpu_physwindow_base);
                }
#if JOE_DEBUG
                else {
                        if (pentry !=
                            (*(current_cpu_datap()->cpu_physwindow_ptep) & (INTEL_PTE_VALID | PG_FRAME | INTEL_PTE_RW)))
                                panic("copyio_phys: pentry != *physwindow_ptep");
                }
#endif
                retval = copyio(ctype, vaddr, window_offset, csize, NULL, which & cppvKmap);

                current_thread()->machine.physwindow_busy = 0;
        }
        return (retval);
}

int
copyinmsg(const user_addr_t user_addr, char *kernel_addr, vm_size_t nbytes)
{
        return (copyio(COPYIN, user_addr, kernel_addr, nbytes, NULL, 0));
}    

int
copyin(const user_addr_t user_addr, char *kernel_addr, vm_size_t nbytes)
{
        return (copyio(COPYIN, user_addr, kernel_addr, nbytes, NULL, 0));
}

int
copyinstr(const user_addr_t user_addr,  char *kernel_addr, vm_size_t nbytes, vm_size_t *lencopied)
{
        *lencopied = 0;

        return (copyio(COPYINSTR, user_addr, kernel_addr, nbytes, lencopied, 0));
}

int
copyoutmsg(const char *kernel_addr, user_addr_t user_addr, vm_size_t nbytes)
{
        return (copyio(COPYOUT, user_addr, (char *)(uintptr_t)kernel_addr, nbytes, NULL, 0));
}

int
copyout(const void *kernel_addr, user_addr_t user_addr, vm_size_t nbytes)
{
        return (copyio(COPYOUT, user_addr, (char *)(uintptr_t)kernel_addr, nbytes, NULL, 0));
}


kern_return_t
copypv(addr64_t src64, addr64_t snk64, unsigned int size, int which)
{
        unsigned int lop, csize;
        int bothphys = 0;
        
        KERNEL_DEBUG(0xeff7004c | DBG_FUNC_START, (unsigned)src64,
                     (unsigned)snk64, size, which, 0);

        if ((which & (cppvPsrc | cppvPsnk)) == 0 )                              /* Make sure that only one is virtual */
                panic("copypv: no more than 1 parameter may be virtual\n");     /* Not allowed */

        if ((which & (cppvPsrc | cppvPsnk)) == (cppvPsrc | cppvPsnk))
                bothphys = 1;                                                   /* both are physical */

        while (size) {
          
                if (bothphys) {
                        lop = (unsigned int)(PAGE_SIZE - (snk64 & (PAGE_SIZE - 1)));            /* Assume sink smallest */

                        if (lop > (unsigned int)(PAGE_SIZE - (src64 & (PAGE_SIZE - 1))))
                                lop = (unsigned int)(PAGE_SIZE - (src64 & (PAGE_SIZE - 1)));    /* No, source is smaller */
                } else {
                        /*
                         * only need to compute the resid for the physical page
                         * address... we don't care about where we start/finish in
                         * the virtual since we just call the normal copyin/copyout
                         */
                        if (which & cppvPsrc)
                                lop = (unsigned int)(PAGE_SIZE - (src64 & (PAGE_SIZE - 1)));
                        else
                                lop = (unsigned int)(PAGE_SIZE - (snk64 & (PAGE_SIZE - 1)));
                }
                csize = size;                                           /* Assume we can copy it all */
                if (lop < size)
                        csize = lop;                                    /* Nope, we can't do it all */
#if 0           
                /*
                 * flush_dcache64 is currently a nop on the i386... 
                 * it's used when copying to non-system memory such
                 * as video capture cards... on PPC there was a need
                 * to flush due to how we mapped this memory... not
                 * sure if it's needed on i386.
                 */
                if (which & cppvFsrc)
                        flush_dcache64(src64, csize, 1);                /* If requested, flush source before move */
                if (which & cppvFsnk)
                        flush_dcache64(snk64, csize, 1);                /* If requested, flush sink before move */
#endif
                if (bothphys)
                        bcopy_phys(src64, snk64, csize);                /* Do a physical copy, virtually */
                else {
                        if (copyio_phys(src64, snk64, csize, which))
                                return (KERN_FAILURE);
                }
#if 0
                if (which & cppvFsrc)
                        flush_dcache64(src64, csize, 1);        /* If requested, flush source after move */
                if (which & cppvFsnk)
                        flush_dcache64(snk64, csize, 1);        /* If requested, flush sink after move */
#endif
                size   -= csize;                                        /* Calculate what is left */
                snk64 += csize;                                 /* Bump sink to next physical address */
                src64 += csize;                                 /* Bump source to next physical address */
        }
        KERNEL_DEBUG(0xeff7004c | DBG_FUNC_END, (unsigned)src64,
                     (unsigned)snk64, size, which, 0);

        return KERN_SUCCESS;
}

#if !MACH_KDP
void
kdp_register_callout(void)
{
}
#endif

#if !CONFIG_VMX
int host_vmxon(boolean_t exclusive __unused)
{
        return VMX_UNSUPPORTED;
}

void host_vmxoff(void)
{
        return;
}
#endif