xnu-1699.22.81.tar.gz

[apple/xnu.git] / osfmk / x86_64 / pmap.c

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 * This file contains Original Code and/or Modifications of Original Code
 * as defined in and that are subject to the Apple Public Source License
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/*
 * @OSF_COPYRIGHT@
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/*
 * Mach Operating System
 * Copyright (c) 1991,1990,1989,1988 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.
 */
/*
 */

/*
 *      File:   pmap.c
 *      Author: Avadis Tevanian, Jr., Michael Wayne Young
 *      (These guys wrote the Vax version)
 *
 *      Physical Map management code for Intel i386, i486, and i860.
 *
 *      Manages physical address maps.
 *
 *      In addition to hardware address maps, this
 *      module is called upon to provide software-use-only
 *      maps which may or may not be stored in the same
 *      form as hardware maps.  These pseudo-maps are
 *      used to store intermediate results from copy
 *      operations to and from address spaces.
 *
 *      Since the information managed by this module is
 *      also stored by the logical address mapping module,
 *      this module may throw away valid virtual-to-physical
 *      mappings at almost any time.  However, invalidations
 *      of virtual-to-physical mappings must be done as
 *      requested.
 *
 *      In order to cope with hardware architectures which
 *      make virtual-to-physical map invalidates expensive,
 *      this module may delay invalidate or reduced protection
 *      operations until such time as they are actually
 *      necessary.  This module is given full information as
 *      to which processors are currently using which maps,
 *      and to when physical maps must be made correct.
 */

#include <string.h>
#include <mach_kdb.h>
#include <mach_ldebug.h>

#include <libkern/OSAtomic.h>

#include <mach/machine/vm_types.h>

#include <mach/boolean.h>
#include <kern/thread.h>
#include <kern/zalloc.h>
#include <kern/queue.h>
#include <kern/mach_param.h>

#include <kern/lock.h>
#include <kern/kalloc.h>
#include <kern/spl.h>

#include <vm/pmap.h>
#include <vm/vm_map.h>
#include <vm/vm_kern.h>
#include <mach/vm_param.h>
#include <mach/vm_prot.h>
#include <vm/vm_object.h>
#include <vm/vm_page.h>

#include <mach/machine/vm_param.h>
#include <machine/thread.h>

#include <kern/misc_protos.h>                   /* prototyping */
#include <i386/misc_protos.h>
#include <i386/i386_lowmem.h>
#include <x86_64/lowglobals.h>

#include <i386/cpuid.h>
#include <i386/cpu_data.h>
#include <i386/cpu_number.h>
#include <i386/machine_cpu.h>
#include <i386/seg.h>
#include <i386/serial_io.h>
#include <i386/cpu_capabilities.h>
#include <i386/machine_routines.h>
#include <i386/proc_reg.h>
#include <i386/tsc.h>
#include <i386/pmap_internal.h>
#include <i386/pmap_pcid.h>

#if     MACH_KDB
#include <ddb/db_command.h>
#include <ddb/db_output.h>
#include <ddb/db_sym.h>
#include <ddb/db_print.h>
#endif  /* MACH_KDB */

#include <vm/vm_protos.h>

#include <i386/mp.h>
#include <i386/mp_desc.h>


#ifdef IWANTTODEBUG
#undef  DEBUG
#define DEBUG 1
#define POSTCODE_DELAY 1
#include <i386/postcode.h>
#endif /* IWANTTODEBUG */

#ifdef  PMAP_DEBUG
#define DBG(x...)       kprintf("DBG: " x)
#else
#define DBG(x...)
#endif
/* Compile time assert to ensure adjacency/alignment of per-CPU data fields used
 * in the trampolines for kernel/user boundary TLB coherency.
 */
char pmap_cpu_data_assert[(((offsetof(cpu_data_t, cpu_tlb_invalid) - offsetof(cpu_data_t, cpu_active_cr3)) == 8) && (offsetof(cpu_data_t, cpu_active_cr3) % 64 == 0)) ? 1 : -1];
boolean_t pmap_trace = FALSE;

boolean_t       no_shared_cr3 = DEBUG;          /* TRUE for DEBUG by default */

int nx_enabled = 1;                     /* enable no-execute protection */
int allow_data_exec  = VM_ABI_32;       /* 32-bit apps may execute data by default, 64-bit apps may not */
int allow_stack_exec = 0;               /* No apps may execute from the stack by default */

const boolean_t cpu_64bit  = TRUE; /* Mais oui! */

uint64_t max_preemption_latency_tsc = 0;

pv_hashed_entry_t     *pv_hash_table;  /* hash lists */

uint32_t npvhash = 0;

pv_hashed_entry_t       pv_hashed_free_list = PV_HASHED_ENTRY_NULL;
pv_hashed_entry_t       pv_hashed_kern_free_list = PV_HASHED_ENTRY_NULL;
decl_simple_lock_data(,pv_hashed_free_list_lock)
decl_simple_lock_data(,pv_hashed_kern_free_list_lock)
decl_simple_lock_data(,pv_hash_table_lock)

zone_t          pv_hashed_list_zone;    /* zone of pv_hashed_entry structures */

/*
 *      First and last physical addresses that we maintain any information
 *      for.  Initialized to zero so that pmap operations done before
 *      pmap_init won't touch any non-existent structures.
 */
boolean_t       pmap_initialized = FALSE;/* Has pmap_init completed? */

static struct vm_object kptobj_object_store;
static struct vm_object kpml4obj_object_store;
static struct vm_object kpdptobj_object_store;

/*
 *      Array of physical page attribites for managed pages.
 *      One byte per physical page.
 */
char            *pmap_phys_attributes;
unsigned int    last_managed_page = 0;

/*
 *      Amount of virtual memory mapped by one
 *      page-directory entry.
 */

uint64_t pde_mapped_size = PDE_MAPPED_SIZE;

unsigned pmap_memory_region_count;
unsigned pmap_memory_region_current;

pmap_memory_region_t pmap_memory_regions[PMAP_MEMORY_REGIONS_SIZE];

/*
 *      Other useful macros.
 */
#define current_pmap()          (vm_map_pmap(current_thread()->map))

struct pmap     kernel_pmap_store;
pmap_t          kernel_pmap;

pd_entry_t      high_shared_pde;
pd_entry_t      commpage64_pde;

struct zone     *pmap_zone;             /* zone of pmap structures */

struct zone     *pmap_anchor_zone;
int             pmap_debug = 0;         /* flag for debugging prints */

unsigned int    inuse_ptepages_count = 0;
long long       alloc_ptepages_count __attribute__((aligned(8))) = 0; /* aligned for atomic access */
unsigned int    bootstrap_wired_pages = 0;
int             pt_fake_zone_index = -1;

extern  long    NMIPI_acks;

boolean_t       kernel_text_ps_4K = TRUE;
boolean_t       wpkernel = TRUE;

extern char     end;

static int      nkpt;

pt_entry_t     *DMAP1, *DMAP2;
caddr_t         DADDR1;
caddr_t         DADDR2;

/*
 * unlinks the pv_hashed_entry_t pvh from the singly linked hash chain.
 * properly deals with the anchor.
 * must be called with the hash locked, does not unlock it
 */


/*
 *      Map memory at initialization.  The physical addresses being
 *      mapped are not managed and are never unmapped.
 *
 *      For now, VM is already on, we only need to map the
 *      specified memory.
 */
vm_offset_t
pmap_map(
        vm_offset_t     virt,
        vm_map_offset_t start_addr,
        vm_map_offset_t end_addr,
        vm_prot_t       prot,
        unsigned int    flags)
{
        int             ps;

        ps = PAGE_SIZE;
        while (start_addr < end_addr) {
                pmap_enter(kernel_pmap, (vm_map_offset_t)virt,
                           (ppnum_t) i386_btop(start_addr), prot, flags, FALSE);
                virt += ps;
                start_addr += ps;
        }
        return(virt);
}

/*
 *      Back-door routine for mapping kernel VM at initialization.  
 *      Useful for mapping memory outside the range
 *      Sets no-cache, A, D.
 *      Otherwise like pmap_map.
 */
vm_offset_t
pmap_map_bd(
        vm_offset_t     virt,
        vm_map_offset_t start_addr,
        vm_map_offset_t end_addr,
        vm_prot_t       prot,
        unsigned int    flags)
{
        pt_entry_t      template;
        pt_entry_t      *pte;
        spl_t           spl;
        vm_offset_t     base = virt;
        template = pa_to_pte(start_addr)
                | INTEL_PTE_REF
                | INTEL_PTE_MOD
                | INTEL_PTE_WIRED
                | INTEL_PTE_VALID;

        if (flags & (VM_MEM_NOT_CACHEABLE | VM_WIMG_USE_DEFAULT)) {
                template |= INTEL_PTE_NCACHE;
                if (!(flags & (VM_MEM_GUARDED | VM_WIMG_USE_DEFAULT)))
                        template |= INTEL_PTE_PTA;
        }
        if (prot & VM_PROT_WRITE)
                template |= INTEL_PTE_WRITE;

        while (start_addr < end_addr) {
                spl = splhigh();
                pte = pmap_pte(kernel_pmap, (vm_map_offset_t)virt);
                if (pte == PT_ENTRY_NULL) {
                        panic("pmap_map_bd: Invalid kernel address\n");
                }
                pmap_store_pte(pte, template);
                splx(spl);
                pte_increment_pa(template);
                virt += PAGE_SIZE;
                start_addr += PAGE_SIZE;
        }
        (void)base;
        PMAP_UPDATE_TLBS(kernel_pmap, base, base + end_addr - start_addr);
        return(virt);
}

extern  char                    *first_avail;
extern  vm_offset_t             virtual_avail, virtual_end;
extern  pmap_paddr_t            avail_start, avail_end;
extern  vm_offset_t             sHIB;
extern  vm_offset_t             eHIB;
extern  vm_offset_t             stext;
extern  vm_offset_t             etext;
extern  vm_offset_t             sdata;

extern void                     *KPTphys;

void
pmap_cpu_init(void)
{
        /*
         * Here early in the life of a processor (from cpu_mode_init()).
         * Ensure global page feature is disabled at this point.
         */

        set_cr4(get_cr4() &~ CR4_PGE);

        /*
         * Initialize the per-cpu, TLB-related fields.
         */
        current_cpu_datap()->cpu_kernel_cr3 = kernel_pmap->pm_cr3;
        current_cpu_datap()->cpu_active_cr3 = kernel_pmap->pm_cr3;
        current_cpu_datap()->cpu_tlb_invalid = FALSE;
        current_cpu_datap()->cpu_task_map = TASK_MAP_64BIT;
        pmap_pcid_configure();
}



/*
 *      Bootstrap the system enough to run with virtual memory.
 *      Map the kernel's code and data, and allocate the system page table.
 *      Called with mapping OFF.  Page_size must already be set.
 */

void
pmap_bootstrap(
        __unused vm_offset_t    load_start,
        __unused boolean_t      IA32e)
{
#if NCOPY_WINDOWS > 0
        vm_offset_t     va;
        int i;
#endif
        assert(IA32e);

        vm_last_addr = VM_MAX_KERNEL_ADDRESS;   /* Set the highest address
                                                 * known to VM */
        /*
         *      The kernel's pmap is statically allocated so we don't
         *      have to use pmap_create, which is unlikely to work
         *      correctly at this part of the boot sequence.
         */

        kernel_pmap = &kernel_pmap_store;
        kernel_pmap->ref_count = 1;
        kernel_pmap->nx_enabled = FALSE;
        kernel_pmap->pm_task_map = TASK_MAP_64BIT;
        kernel_pmap->pm_obj = (vm_object_t) NULL;
        kernel_pmap->dirbase = (pd_entry_t *)((uintptr_t)IdlePTD);
        kernel_pmap->pm_pdpt = (pd_entry_t *) ((uintptr_t)IdlePDPT);
        kernel_pmap->pm_pml4 = IdlePML4;
        kernel_pmap->pm_cr3 = (uintptr_t)ID_MAP_VTOP(IdlePML4);
        pmap_pcid_initialize_kernel(kernel_pmap);

        

        current_cpu_datap()->cpu_kernel_cr3 = (addr64_t) kernel_pmap->pm_cr3;

        nkpt = NKPT;
        OSAddAtomic(NKPT,  &inuse_ptepages_count);
        OSAddAtomic64(NKPT,  &alloc_ptepages_count);
        bootstrap_wired_pages = NKPT;

        virtual_avail = (vm_offset_t)(VM_MIN_KERNEL_ADDRESS) + (vm_offset_t)first_avail;
        virtual_end = (vm_offset_t)(VM_MAX_KERNEL_ADDRESS);

#if NCOPY_WINDOWS > 0
        /*
         * Reserve some special page table entries/VA space for temporary
         * mapping of pages.
         */
#define SYSMAP(c, p, v, n)      \
        v = (c)va; va += ((n)*INTEL_PGBYTES);

        va = virtual_avail;

        for (i=0; i<PMAP_NWINDOWS; i++) {
#if 1
            kprintf("trying to do SYSMAP idx %d %p\n", i,
                current_cpu_datap());
            kprintf("cpu_pmap %p\n", current_cpu_datap()->cpu_pmap);
            kprintf("mapwindow %p\n", current_cpu_datap()->cpu_pmap->mapwindow);
            kprintf("two stuff %p %p\n",
                   (void *)(current_cpu_datap()->cpu_pmap->mapwindow[i].prv_CMAP),
                   (void *)(current_cpu_datap()->cpu_pmap->mapwindow[i].prv_CADDR));
#endif
            SYSMAP(caddr_t,
                   (current_cpu_datap()->cpu_pmap->mapwindow[i].prv_CMAP),
                   (current_cpu_datap()->cpu_pmap->mapwindow[i].prv_CADDR),
                   1);
            current_cpu_datap()->cpu_pmap->mapwindow[i].prv_CMAP =
                &(current_cpu_datap()->cpu_pmap->mapwindow[i].prv_CMAP_store);
            *current_cpu_datap()->cpu_pmap->mapwindow[i].prv_CMAP = 0;
        }

        /* DMAP user for debugger */
        SYSMAP(caddr_t, DMAP1, DADDR1, 1);
        SYSMAP(caddr_t, DMAP2, DADDR2, 1);  /* XXX temporary - can remove */

        virtual_avail = va;
#endif

        if (PE_parse_boot_argn("npvhash", &npvhash, sizeof (npvhash))) {
                if (0 != ((npvhash + 1) & npvhash)) {
                        kprintf("invalid hash %d, must be ((2^N)-1), "
                                "using default %d\n", npvhash, NPVHASH);
                        npvhash = NPVHASH;
                }
        } else {
                npvhash = NPVHASH;
        }

        simple_lock_init(&kernel_pmap->lock, 0);
        simple_lock_init(&pv_hashed_free_list_lock, 0);
        simple_lock_init(&pv_hashed_kern_free_list_lock, 0);
        simple_lock_init(&pv_hash_table_lock,0);

        pmap_cpu_init();

        if (pmap_pcid_ncpus)
                printf("PMAP: PCID enabled\n");

        boot_args *args = (boot_args *)PE_state.bootArgs;
        if (args->efiMode == kBootArgsEfiMode32) {
                printf("EFI32: kernel virtual space limited to 4GB\n");
                virtual_end = VM_MAX_KERNEL_ADDRESS_EFI32;
        }
        kprintf("Kernel virtual space from 0x%lx to 0x%lx.\n",
                        (long)KERNEL_BASE, (long)virtual_end);
        kprintf("Available physical space from 0x%llx to 0x%llx\n",
                        avail_start, avail_end);

        /*
         * The -no_shared_cr3 boot-arg is a debugging feature (set by default
         * in the DEBUG kernel) to force the kernel to switch to its own map
         * (and cr3) when control is in kernelspace. The kernel's map does not
         * include (i.e. share) userspace so wild references will cause
         * a panic. Only copyin and copyout are exempt from this. 
         */
        (void) PE_parse_boot_argn("-no_shared_cr3",
                                  &no_shared_cr3, sizeof (no_shared_cr3));
        if (no_shared_cr3)
                kprintf("Kernel not sharing user map\n");
                
#ifdef  PMAP_TRACES
        if (PE_parse_boot_argn("-pmap_trace", &pmap_trace, sizeof (pmap_trace))) {
                kprintf("Kernel traces for pmap operations enabled\n");
        }       
#endif  /* PMAP_TRACES */
}

void
pmap_virtual_space(
        vm_offset_t *startp,
        vm_offset_t *endp)
{
        *startp = virtual_avail;
        *endp = virtual_end;
}

/*
 *      Initialize the pmap module.
 *      Called by vm_init, to initialize any structures that the pmap
 *      system needs to map virtual memory.
 */
void
pmap_init(void)
{
        long                    npages;
        vm_offset_t             addr;
        vm_size_t               s, vsize;
        vm_map_offset_t         vaddr;
        ppnum_t ppn;


        kernel_pmap->pm_obj_pml4 = &kpml4obj_object_store;
        _vm_object_allocate((vm_object_size_t)NPML4PGS, &kpml4obj_object_store);

        kernel_pmap->pm_obj_pdpt = &kpdptobj_object_store;
        _vm_object_allocate((vm_object_size_t)NPDPTPGS, &kpdptobj_object_store);

        kernel_pmap->pm_obj = &kptobj_object_store;
        _vm_object_allocate((vm_object_size_t)NPDEPGS, &kptobj_object_store);

        /*
         *      Allocate memory for the pv_head_table and its lock bits,
         *      the modify bit array, and the pte_page table.
         */

        /*
         * zero bias all these arrays now instead of off avail_start
         * so we cover all memory
         */

        npages = i386_btop(avail_end);
        s = (vm_size_t) (sizeof(struct pv_rooted_entry) * npages
                         + (sizeof (struct pv_hashed_entry_t *) * (npvhash+1))
                         + pv_lock_table_size(npages)
                         + pv_hash_lock_table_size((npvhash+1))
                                + npages);

        s = round_page(s);
        if (kernel_memory_allocate(kernel_map, &addr, s, 0,
                                   KMA_KOBJECT | KMA_PERMANENT)
            != KERN_SUCCESS)
                panic("pmap_init");

        memset((char *)addr, 0, s);

        vaddr = addr;
        vsize = s;

#if PV_DEBUG
        if (0 == npvhash) panic("npvhash not initialized");
#endif

        /*
         *      Allocate the structures first to preserve word-alignment.
         */
        pv_head_table = (pv_rooted_entry_t) addr;
        addr = (vm_offset_t) (pv_head_table + npages);

        pv_hash_table = (pv_hashed_entry_t *)addr;
        addr = (vm_offset_t) (pv_hash_table + (npvhash + 1));

        pv_lock_table = (char *) addr;
        addr = (vm_offset_t) (pv_lock_table + pv_lock_table_size(npages));

        pv_hash_lock_table = (char *) addr;
        addr = (vm_offset_t) (pv_hash_lock_table + pv_hash_lock_table_size((npvhash+1)));

        pmap_phys_attributes = (char *) addr;

        ppnum_t  last_pn = i386_btop(avail_end);
        unsigned int i;
        pmap_memory_region_t *pmptr = pmap_memory_regions;
        for (i = 0; i < pmap_memory_region_count; i++, pmptr++) {
                if (pmptr->type != kEfiConventionalMemory)
                        continue;
                unsigned int pn;
                for (pn = pmptr->base; pn <= pmptr->end; pn++) {
                        if (pn < last_pn) {
                                pmap_phys_attributes[pn] |= PHYS_MANAGED;

                                if (pn > last_managed_page)
                                        last_managed_page = pn;

                                if (pn < lowest_lo)
                                        pmap_phys_attributes[pn] |= PHYS_NOENCRYPT;
                                else if (pn >= lowest_hi && pn <= highest_hi)
                                        pmap_phys_attributes[pn] |= PHYS_NOENCRYPT;
                        }
                }
        }
        while (vsize) {
                ppn = pmap_find_phys(kernel_pmap, vaddr);

                pmap_phys_attributes[ppn] |= PHYS_NOENCRYPT;

                vaddr += PAGE_SIZE;
                vsize -= PAGE_SIZE;
        }
        /*
         *      Create the zone of physical maps,
         *      and of the physical-to-virtual entries.
         */
        s = (vm_size_t) sizeof(struct pmap);
        pmap_zone = zinit(s, 400*s, 4096, "pmap"); /* XXX */
        zone_change(pmap_zone, Z_NOENCRYPT, TRUE);

        pmap_anchor_zone = zinit(PAGE_SIZE, task_max, PAGE_SIZE, "pagetable anchors");
        zone_change(pmap_anchor_zone, Z_NOENCRYPT, TRUE);

#if     ZONE_DEBUG
        /* The anchor is required to be page aligned. Zone debugging adds
         * padding which may violate that requirement. Disable it
         * to avoid assumptions.
         */
        zone_debug_disable(pmap_anchor_zone);
#endif  

        s = (vm_size_t) sizeof(struct pv_hashed_entry);
        pv_hashed_list_zone = zinit(s, 10000*s /* Expandable zone */,
            4096 * 3 /* LCM x86_64*/, "pv_list");
        zone_change(pv_hashed_list_zone, Z_NOENCRYPT, TRUE);

        /* create pv entries for kernel pages mapped by low level
           startup code.  these have to exist so we can pmap_remove()
           e.g. kext pages from the middle of our addr space */

        vaddr = (vm_map_offset_t) VM_MIN_KERNEL_ADDRESS;
        for (ppn = VM_MIN_KERNEL_PAGE; ppn < i386_btop(avail_start); ppn++) {
                pv_rooted_entry_t pv_e;

                pv_e = pai_to_pvh(ppn);
                pv_e->va = vaddr;
                vaddr += PAGE_SIZE;
                pv_e->pmap = kernel_pmap;
                queue_init(&pv_e->qlink);
        }
        pmap_initialized = TRUE;

        max_preemption_latency_tsc = tmrCvt((uint64_t)MAX_PREEMPTION_LATENCY_NS, tscFCvtn2t);

        /*
         * Ensure the kernel's PML4 entry exists for the basement
         * before this is shared with any user.
         */
        pmap_expand_pml4(kernel_pmap, KERNEL_BASEMENT);
}

/*
 * Called once VM is fully initialized so that we can release unused
 * sections of low memory to the general pool.
 * Also complete the set-up of identity-mapped sections of the kernel:
 *  1) write-protect kernel text
 *  2) map kernel text using large pages if possible
 *  3) read and write-protect page zero (for K32)
 *  4) map the global page at the appropriate virtual address.
 *
 * Use of large pages
 * ------------------
 * To effectively map and write-protect all kernel text pages, the text
 * must be 2M-aligned at the base, and the data section above must also be
 * 2M-aligned. That is, there's padding below and above. This is achieved
 * through linker directives. Large pages are used only if this alignment
 * exists (and not overriden by the -kernel_text_page_4K boot-arg). The
 * memory layout is:
 * 
 *                       :                :
 *                       |     __DATA     |
 *               sdata:  ==================  2Meg
 *                       |                |
 *                       |  zero-padding  |
 *                       |                |
 *               etext:  ------------------ 
 *                       |                |
 *                       :                :
 *                       |                |
 *                       |     __TEXT     |
 *                       |                |
 *                       :                :
 *                       |                |
 *               stext:  ==================  2Meg
 *                       |                |
 *                       |  zero-padding  |
 *                       |                |
 *               eHIB:   ------------------ 
 *                       |     __HIB      |
 *                       :                :
 *
 * Prior to changing the mapping from 4K to 2M, the zero-padding pages
 * [eHIB,stext] and [etext,sdata] are ml_static_mfree()'d. Then all the
 * 4K pages covering [stext,etext] are coalesced as 2M large pages.
 * The now unused level-1 PTE pages are also freed.
 */
extern uint32_t pmap_reserved_ranges;
void
pmap_lowmem_finalize(void)
{
        spl_t           spl;
        int             i;

        /* Check the kernel is linked at the expected base address */
        if (i386_btop(kvtophys((vm_offset_t) &IdlePML4)) !=
            I386_KERNEL_IMAGE_BASE_PAGE)
                panic("pmap_lowmem_finalize() unexpected kernel base address");

        /*
         * Update wired memory statistics for early boot pages
         */
        PMAP_ZINFO_PALLOC(bootstrap_wired_pages * PAGE_SIZE);

        /*
         * Free all pages in pmap regions below the base:
         * rdar://6332712
         *      We can't free all the pages to VM that EFI reports available.
         *      Pages in the range 0xc0000-0xff000 aren't safe over sleep/wake.
         *      There's also a size miscalculation here: pend is one page less
         *      than it should be but this is not fixed to be backwards
         *      compatible.
         *      Due to this current EFI limitation, we take only the first
         *      entry in the memory region table. However, the loop is retained
         *      (with the intended termination criteria commented out) in the
         *      hope that some day we can free all low-memory ranges.
         */
        for (i = 0;
//           pmap_memory_regions[i].end <= I386_KERNEL_IMAGE_BASE_PAGE;
             i < 1  && (pmap_reserved_ranges == 0);
             i++) {
                vm_offset_t     pbase = (vm_offset_t)i386_ptob(pmap_memory_regions[i].base);
                vm_offset_t     pend  = (vm_offset_t)i386_ptob(pmap_memory_regions[i].end);
//              vm_offset_t     pend  = i386_ptob(pmap_memory_regions[i].end+1);

                DBG("ml_static_mfree(%p,%p) for pmap region %d\n",
                    (void *) ml_static_ptovirt(pbase),
                    (void *) (pend - pbase), i);
                ml_static_mfree(ml_static_ptovirt(pbase), pend - pbase);
        }

        /*
         * If text and data are both 2MB-aligned,
         * we can map text with large-pages,
         * unless the -kernel_text_ps_4K boot-arg overrides.
         */
        if ((stext & I386_LPGMASK) == 0 && (sdata & I386_LPGMASK) == 0) {
                kprintf("Kernel text is 2MB aligned");
                kernel_text_ps_4K = FALSE;
                if (PE_parse_boot_argn("-kernel_text_ps_4K",
                                       &kernel_text_ps_4K,
                                       sizeof (kernel_text_ps_4K)))
                        kprintf(" but will be mapped with 4K pages\n");
                else
                        kprintf(" and will be mapped with 2M pages\n");
        }

        (void) PE_parse_boot_argn("wpkernel", &wpkernel, sizeof (wpkernel));
        if (wpkernel)
                kprintf("Kernel text %p-%p to be write-protected\n",
                        (void *) stext, (void *) etext);

        spl = splhigh();

        /*
         * Scan over text if mappings are to be changed:
         * - Remap kernel text readonly unless the "wpkernel" boot-arg is 0 
         * - Change to large-pages if possible and not overriden.
         */
        if (kernel_text_ps_4K && wpkernel) {
                vm_offset_t     myva;
                for (myva = stext; myva < etext; myva += PAGE_SIZE) {
                        pt_entry_t     *ptep;

                        ptep = pmap_pte(kernel_pmap, (vm_map_offset_t)myva);
                        if (ptep)
                                pmap_store_pte(ptep, *ptep & ~INTEL_PTE_RW);
                }
        }

        if (!kernel_text_ps_4K) {
                vm_offset_t     myva;

                /*
                 * Release zero-filled page padding used for 2M-alignment.
                 */
                DBG("ml_static_mfree(%p,%p) for padding below text\n",
                        (void *) eHIB, (void *) (stext - eHIB));
                ml_static_mfree(eHIB, stext - eHIB);
                DBG("ml_static_mfree(%p,%p) for padding above text\n",
                        (void *) etext, (void *) (sdata - etext));
                ml_static_mfree(etext, sdata - etext);

                /*
                 * Coalesce text pages into large pages.
                 */
                for (myva = stext; myva < sdata; myva += I386_LPGBYTES) {
                        pt_entry_t      *ptep;
                        vm_offset_t     pte_phys;
                        pt_entry_t      *pdep;
                        pt_entry_t      pde;

                        pdep = pmap_pde(kernel_pmap, (vm_map_offset_t)myva);
                        ptep = pmap_pte(kernel_pmap, (vm_map_offset_t)myva);
                        DBG("myva: %p pdep: %p ptep: %p\n",
                                (void *) myva, (void *) pdep, (void *) ptep);
                        if ((*ptep & INTEL_PTE_VALID) == 0)
                                continue;
                        pte_phys = (vm_offset_t)(*ptep & PG_FRAME);
                        pde = *pdep & PTMASK;   /* page attributes from pde */
                        pde |= INTEL_PTE_PS;    /* make it a 2M entry */
                        pde |= pte_phys;        /* take page frame from pte */

                        if (wpkernel)
                                pde &= ~INTEL_PTE_RW;
                        DBG("pmap_store_pte(%p,0x%llx)\n",
                                (void *)pdep, pde);
                        pmap_store_pte(pdep, pde);

                        /*
                         * Free the now-unused level-1 pte.
                         * Note: ptep is a virtual address to the pte in the
                         *   recursive map. We can't use this address to free
                         *   the page. Instead we need to compute its address
                         *   in the Idle PTEs in "low memory".
                         */
                        vm_offset_t vm_ptep = (vm_offset_t) KPTphys
                                                + (pte_phys >> PTPGSHIFT);
                        DBG("ml_static_mfree(%p,0x%x) for pte\n",
                                (void *) vm_ptep, PAGE_SIZE);
                        ml_static_mfree(vm_ptep, PAGE_SIZE);
                }

                /* Change variable read by sysctl machdep.pmap */
                pmap_kernel_text_ps = I386_LPGBYTES;
        }

        /* map lowmem global page into fixed addr */
        pt_entry_t *pte = NULL;
        if (0 == (pte = pmap_pte(kernel_pmap,
                                 VM_MIN_KERNEL_LOADED_ADDRESS + 0x2000)))
                panic("lowmem pte");
        /* make sure it is defined on page boundary */
        assert(0 == ((vm_offset_t) &lowGlo & PAGE_MASK));
        pmap_store_pte(pte, kvtophys((vm_offset_t)&lowGlo)
                                | INTEL_PTE_REF
                                | INTEL_PTE_MOD
                                | INTEL_PTE_WIRED
                                | INTEL_PTE_VALID
                                | INTEL_PTE_RW);
        splx(spl);
        if (pmap_pcid_ncpus)
                tlb_flush_global();
        else
                flush_tlb_raw();
}

/*
 * this function is only used for debugging fron the vm layer
 */
boolean_t
pmap_verify_free(
                 ppnum_t pn)
{
        pv_rooted_entry_t       pv_h;
        int             pai;
        boolean_t       result;

        assert(pn != vm_page_fictitious_addr);

        if (!pmap_initialized)
                return(TRUE);

        if (pn == vm_page_guard_addr)
                return TRUE;

        pai = ppn_to_pai(pn);
        if (!IS_MANAGED_PAGE(pai))
                return(FALSE);
        pv_h = pai_to_pvh(pn);
        result = (pv_h->pmap == PMAP_NULL);
        return(result);
}

boolean_t
pmap_is_empty(
       pmap_t          pmap,
       vm_map_offset_t va_start,
       vm_map_offset_t va_end)
{
        vm_map_offset_t offset;
        ppnum_t         phys_page;

        if (pmap == PMAP_NULL) {
                return TRUE;
        }

        /*
         * Check the resident page count
         * - if it's zero, the pmap is completely empty.
         * This short-circuit test prevents a virtual address scan which is
         * painfully slow for 64-bit spaces.
         * This assumes the count is correct
         * .. the debug kernel ought to be checking perhaps by page table walk.
         */
        if (pmap->stats.resident_count == 0)
                return TRUE;

        for (offset = va_start;
             offset < va_end;
             offset += PAGE_SIZE_64) {
                phys_page = pmap_find_phys(pmap, offset);
                if (phys_page) {
                        kprintf("pmap_is_empty(%p,0x%llx,0x%llx): "
                                "page %d at 0x%llx\n",
                                pmap, va_start, va_end, phys_page, offset);
                        return FALSE;
                }
        }

        return TRUE;
}


/*
 *      Create and return a physical map.
 *
 *      If the size specified for the map
 *      is zero, the map is an actual physical
 *      map, and may be referenced by the
 *      hardware.
 *
 *      If the size specified is non-zero,
 *      the map will be used in software only, and
 *      is bounded by that size.
 */
pmap_t
pmap_create(
            vm_map_size_t       sz,
            boolean_t           is_64bit)
{
        pmap_t          p;
        vm_size_t       size;
        pml4_entry_t    *pml4;
        pml4_entry_t    *kpml4;

        PMAP_TRACE(PMAP_CODE(PMAP__CREATE) | DBG_FUNC_START,
                   (uint32_t) (sz>>32), (uint32_t) sz, is_64bit, 0, 0);

        size = (vm_size_t) sz;

        /*
         *      A software use-only map doesn't even need a map.
         */

        if (size != 0) {
                return(PMAP_NULL);
        }

        p = (pmap_t) zalloc(pmap_zone);
        if (PMAP_NULL == p)
                panic("pmap_create zalloc");
        /* Zero all fields */
        bzero(p, sizeof(*p));
        /* init counts now since we'll be bumping some */
        simple_lock_init(&p->lock, 0);
        p->stats.resident_count = 0;
        p->stats.resident_max = 0;
        p->stats.wired_count = 0;
        p->ref_count = 1;
        p->nx_enabled = 1;
        p->pm_shared = FALSE;

        p->pm_task_map = is_64bit ? TASK_MAP_64BIT : TASK_MAP_32BIT;;
        if (pmap_pcid_ncpus)
                pmap_pcid_initialize(p);
        p->pm_pml4 = zalloc(pmap_anchor_zone);

        pmap_assert((((uintptr_t)p->pm_pml4) & PAGE_MASK) == 0);

        memset((char *)p->pm_pml4, 0, PAGE_SIZE);

        p->pm_cr3 = (pmap_paddr_t)kvtophys((vm_offset_t)p->pm_pml4);

        /* allocate the vm_objs to hold the pdpt, pde and pte pages */

        p->pm_obj_pml4 = vm_object_allocate((vm_object_size_t)(NPML4PGS));
        if (NULL == p->pm_obj_pml4)
                panic("pmap_create pdpt obj");

        p->pm_obj_pdpt = vm_object_allocate((vm_object_size_t)(NPDPTPGS));
        if (NULL == p->pm_obj_pdpt)
                panic("pmap_create pdpt obj");

        p->pm_obj = vm_object_allocate((vm_object_size_t)(NPDEPGS));
        if (NULL == p->pm_obj)
                panic("pmap_create pte obj");

        /* All pmaps share the kernel's pml4 */
        pml4 = pmap64_pml4(p, 0ULL);
        kpml4 = kernel_pmap->pm_pml4;
        pml4[KERNEL_PML4_INDEX]    = kpml4[KERNEL_PML4_INDEX];
        pml4[KERNEL_KEXTS_INDEX]   = kpml4[KERNEL_KEXTS_INDEX];
        pml4[KERNEL_PHYSMAP_INDEX] = kpml4[KERNEL_PHYSMAP_INDEX];

        PMAP_TRACE(PMAP_CODE(PMAP__CREATE) | DBG_FUNC_START,
                   p, is_64bit, 0, 0, 0);

        return(p);
}

/*
 *      Retire the given physical map from service.
 *      Should only be called if the map contains
 *      no valid mappings.
 */

void
pmap_destroy(pmap_t     p)
{
        int             c;

        if (p == PMAP_NULL)
                return;

        PMAP_TRACE(PMAP_CODE(PMAP__DESTROY) | DBG_FUNC_START,
                   p, 0, 0, 0, 0);

        PMAP_LOCK(p);

        c = --p->ref_count;

        pmap_assert((current_thread() && (current_thread()->map)) ? (current_thread()->map->pmap != p) : TRUE);

        if (c == 0) {
                /* 
                 * If some cpu is not using the physical pmap pointer that it
                 * is supposed to be (see set_dirbase), we might be using the
                 * pmap that is being destroyed! Make sure we are
                 * physically on the right pmap:
                 */
                PMAP_UPDATE_TLBS(p, 0x0ULL, 0xFFFFFFFFFFFFF000ULL);
        }
        if (pmap_pcid_ncpus)
                pmap_destroy_pcid_sync(p);
        PMAP_UNLOCK(p);

        if (c != 0) {
                PMAP_TRACE(PMAP_CODE(PMAP__DESTROY) | DBG_FUNC_END,
                           p, 1, 0, 0, 0);
                pmap_assert(p == kernel_pmap);
                return; /* still in use */
        }

        /*
         *      Free the memory maps, then the
         *      pmap structure.
         */
        int inuse_ptepages = 0;

        zfree(pmap_anchor_zone, p->pm_pml4);

        inuse_ptepages += p->pm_obj_pml4->resident_page_count;
        vm_object_deallocate(p->pm_obj_pml4);

        inuse_ptepages += p->pm_obj_pdpt->resident_page_count;
        vm_object_deallocate(p->pm_obj_pdpt);

        inuse_ptepages += p->pm_obj->resident_page_count;
        vm_object_deallocate(p->pm_obj);

        OSAddAtomic(-inuse_ptepages,  &inuse_ptepages_count);
        PMAP_ZINFO_PFREE(inuse_ptepages * PAGE_SIZE);

        zfree(pmap_zone, p);

        PMAP_TRACE(PMAP_CODE(PMAP__DESTROY) | DBG_FUNC_END,
                   0, 0, 0, 0, 0);
}

/*
 *      Add a reference to the specified pmap.
 */

void
pmap_reference(pmap_t   p)
{
        if (p != PMAP_NULL) {
                PMAP_LOCK(p);
                p->ref_count++;
                PMAP_UNLOCK(p);;
        }
}

/*
 *      Remove phys addr if mapped in specified map
 *
 */
void
pmap_remove_some_phys(
        __unused pmap_t         map,
        __unused ppnum_t         pn)
{

/* Implement to support working set code */

}


/*
 *      Set the physical protection on the
 *      specified range of this map as requested.
 *      Will not increase permissions.
 */
void
pmap_protect(
        pmap_t          map,
        vm_map_offset_t sva,
        vm_map_offset_t eva,
        vm_prot_t       prot)
{
        pt_entry_t      *pde;
        pt_entry_t      *spte, *epte;
        vm_map_offset_t lva;
        vm_map_offset_t orig_sva;
        boolean_t       set_NX;
        int             num_found = 0;

        pmap_intr_assert();

        if (map == PMAP_NULL)
                return;

        if (prot == VM_PROT_NONE) {
                pmap_remove(map, sva, eva);
                return;
        }
        PMAP_TRACE(PMAP_CODE(PMAP__PROTECT) | DBG_FUNC_START,
                   map,
                   (uint32_t) (sva >> 32), (uint32_t) sva,
                   (uint32_t) (eva >> 32), (uint32_t) eva);

        if ((prot & VM_PROT_EXECUTE) || !nx_enabled || !map->nx_enabled)
                set_NX = FALSE;
        else
                set_NX = TRUE;

        PMAP_LOCK(map);

        orig_sva = sva;
        while (sva < eva) {
                lva = (sva + pde_mapped_size) & ~(pde_mapped_size - 1);
                if (lva > eva)
                        lva = eva;
                pde = pmap_pde(map, sva);
                if (pde && (*pde & INTEL_PTE_VALID)) {
                        if (*pde & INTEL_PTE_PS) {
                                /* superpage */
                                spte = pde;
                                epte = spte+1; /* excluded */
                        } else {
                                spte = pmap_pte(map, (sva & ~(pde_mapped_size - 1)));
                                spte = &spte[ptenum(sva)];
                                epte = &spte[intel_btop(lva - sva)];
                        }

                        for (; spte < epte; spte++) {
                                if (!(*spte & INTEL_PTE_VALID))
                                        continue;

                                if (prot & VM_PROT_WRITE)
                                        pmap_update_pte(spte, *spte,
                                                *spte | INTEL_PTE_WRITE);
                                else
                                        pmap_update_pte(spte, *spte,
                                                *spte & ~INTEL_PTE_WRITE);

                                if (set_NX)
                                        pmap_update_pte(spte, *spte,
                                                *spte | INTEL_PTE_NX);
                                else
                                        pmap_update_pte(spte, *spte,
                                                *spte & ~INTEL_PTE_NX);

                                num_found++;
                        }
                }
                sva = lva;
        }
        if (num_found)
                PMAP_UPDATE_TLBS(map, orig_sva, eva);

        PMAP_UNLOCK(map);

        PMAP_TRACE(PMAP_CODE(PMAP__PROTECT) | DBG_FUNC_END,
                   0, 0, 0, 0, 0);

}

/* Map a (possibly) autogenned block */
void
pmap_map_block(
        pmap_t          pmap, 
        addr64_t        va,
        ppnum_t         pa,
        uint32_t        size,
        vm_prot_t       prot,
        int             attr,
        __unused unsigned int   flags)
{
        uint32_t        page;
        int             cur_page_size;

        if (attr & VM_MEM_SUPERPAGE)
                cur_page_size =  SUPERPAGE_SIZE;
        else 
                cur_page_size =  PAGE_SIZE;

        for (page = 0; page < size; page+=cur_page_size/PAGE_SIZE) {
                pmap_enter(pmap, va, pa, prot, attr, TRUE);
                va += cur_page_size;
                pa+=cur_page_size/PAGE_SIZE;
        }
}


void
pmap_expand_pml4(
        pmap_t          map,
        vm_map_offset_t vaddr)
{
        vm_page_t       m;
        pmap_paddr_t    pa;
        uint64_t        i;
        ppnum_t         pn;
        pml4_entry_t    *pml4p;

        DBG("pmap_expand_pml4(%p,%p)\n", map, (void *)vaddr);

        /*
         *      Allocate a VM page for the pml4 page
         */
        while ((m = vm_page_grab()) == VM_PAGE_NULL)
                VM_PAGE_WAIT();

        /*
         *      put the page into the pmap's obj list so it
         *      can be found later.
         */
        pn = m->phys_page;
        pa = i386_ptob(pn);
        i = pml4idx(map, vaddr);

        /*
         *      Zero the page.
         */
        pmap_zero_page(pn);

        vm_page_lockspin_queues();
        vm_page_wire(m);
        vm_page_unlock_queues();

        OSAddAtomic(1,  &inuse_ptepages_count);
        OSAddAtomic64(1,  &alloc_ptepages_count);
        PMAP_ZINFO_PALLOC(PAGE_SIZE);

        /* Take the oject lock (mutex) before the PMAP_LOCK (spinlock) */
        vm_object_lock(map->pm_obj_pml4);

        PMAP_LOCK(map);
        /*
         *      See if someone else expanded us first
         */
        if (pmap64_pdpt(map, vaddr) != PDPT_ENTRY_NULL) {
                PMAP_UNLOCK(map);
                vm_object_unlock(map->pm_obj_pml4);

                VM_PAGE_FREE(m);

                OSAddAtomic(-1,  &inuse_ptepages_count);
                PMAP_ZINFO_PFREE(PAGE_SIZE);
                return;
        }

#if 0 /* DEBUG */
       if (0 != vm_page_lookup(map->pm_obj_pml4, (vm_object_offset_t)i)) {
               panic("pmap_expand_pml4: obj not empty, pmap %p pm_obj %p vaddr 0x%llx i 0x%llx\n",
                     map, map->pm_obj_pml4, vaddr, i);
       }
#endif
        vm_page_insert(m, map->pm_obj_pml4, (vm_object_offset_t)i);
        vm_object_unlock(map->pm_obj_pml4);

        /*
         *      Set the page directory entry for this page table.
         */
        pml4p = pmap64_pml4(map, vaddr); /* refetch under lock */

        pmap_store_pte(pml4p, pa_to_pte(pa)
                                | INTEL_PTE_VALID
                                | INTEL_PTE_USER
                                | INTEL_PTE_WRITE);

        PMAP_UNLOCK(map);

        return;
}

void
pmap_expand_pdpt(
                 pmap_t map,
                 vm_map_offset_t vaddr)
{
        vm_page_t       m;
        pmap_paddr_t    pa;
        uint64_t        i;
        ppnum_t         pn;
        pdpt_entry_t    *pdptp;

        DBG("pmap_expand_pdpt(%p,%p)\n", map, (void *)vaddr);

        while ((pdptp = pmap64_pdpt(map, vaddr)) == PDPT_ENTRY_NULL) {
                pmap_expand_pml4(map, vaddr);
        }

        /*
         *      Allocate a VM page for the pdpt page
         */
        while ((m = vm_page_grab()) == VM_PAGE_NULL)
                VM_PAGE_WAIT();

        /*
         *      put the page into the pmap's obj list so it
         *      can be found later.
         */
        pn = m->phys_page;
        pa = i386_ptob(pn);
        i = pdptidx(map, vaddr);

        /*
         *      Zero the page.
         */
        pmap_zero_page(pn);

        vm_page_lockspin_queues();
        vm_page_wire(m);
        vm_page_unlock_queues();

        OSAddAtomic(1,  &inuse_ptepages_count);
        OSAddAtomic64(1,  &alloc_ptepages_count);
        PMAP_ZINFO_PALLOC(PAGE_SIZE);

        /* Take the oject lock (mutex) before the PMAP_LOCK (spinlock) */
        vm_object_lock(map->pm_obj_pdpt);

        PMAP_LOCK(map);
        /*
         *      See if someone else expanded us first
         */
        if (pmap64_pde(map, vaddr) != PD_ENTRY_NULL) {
                PMAP_UNLOCK(map);
                vm_object_unlock(map->pm_obj_pdpt);

                VM_PAGE_FREE(m);

                OSAddAtomic(-1,  &inuse_ptepages_count);
                PMAP_ZINFO_PFREE(PAGE_SIZE);
                return;
        }

#if 0 /* DEBUG */
       if (0 != vm_page_lookup(map->pm_obj_pdpt, (vm_object_offset_t)i)) {
               panic("pmap_expand_pdpt: obj not empty, pmap %p pm_obj %p vaddr 0x%llx i 0x%llx\n",
                     map, map->pm_obj_pdpt, vaddr, i);
       }
#endif
        vm_page_insert(m, map->pm_obj_pdpt, (vm_object_offset_t)i);
        vm_object_unlock(map->pm_obj_pdpt);

        /*
         *      Set the page directory entry for this page table.
         */
        pdptp = pmap64_pdpt(map, vaddr); /* refetch under lock */

        pmap_store_pte(pdptp, pa_to_pte(pa)
                                | INTEL_PTE_VALID
                                | INTEL_PTE_USER
                                | INTEL_PTE_WRITE);

        PMAP_UNLOCK(map);

        return;

}



/*
 *      Routine:        pmap_expand
 *
 *      Expands a pmap to be able to map the specified virtual address.
 *
 *      Allocates new virtual memory for the P0 or P1 portion of the
 *      pmap, then re-maps the physical pages that were in the old
 *      pmap to be in the new pmap.
 *
 *      Must be called with the pmap system and the pmap unlocked,
 *      since these must be unlocked to use vm_allocate or vm_deallocate.
 *      Thus it must be called in a loop that checks whether the map
 *      has been expanded enough.
 *      (We won't loop forever, since page tables aren't shrunk.)
 */
void
pmap_expand(
        pmap_t          map,
        vm_map_offset_t vaddr)
{
        pt_entry_t              *pdp;
        register vm_page_t      m;
        register pmap_paddr_t   pa;
        uint64_t                i;
        ppnum_t                 pn;


        /*
         * For the kernel, the virtual address must be in or above the basement
         * which is for kexts and is in the 512GB immediately below the kernel..
         * XXX - should use VM_MIN_KERNEL_AND_KEXT_ADDRESS not KERNEL_BASEMENT
         */
        if (map == kernel_pmap && 
            !(vaddr >= KERNEL_BASEMENT && vaddr <= VM_MAX_KERNEL_ADDRESS))
                panic("pmap_expand: bad vaddr 0x%llx for kernel pmap", vaddr);


        while ((pdp = pmap64_pde(map, vaddr)) == PD_ENTRY_NULL) {
                /* need room for another pde entry */
                pmap_expand_pdpt(map, vaddr);
        }

        /*
         *      Allocate a VM page for the pde entries.
         */
        while ((m = vm_page_grab()) == VM_PAGE_NULL)
                VM_PAGE_WAIT();

        /*
         *      put the page into the pmap's obj list so it
         *      can be found later.
         */
        pn = m->phys_page;
        pa = i386_ptob(pn);
        i = pdeidx(map, vaddr);

        /*
         *      Zero the page.
         */
        pmap_zero_page(pn);

        vm_page_lockspin_queues();
        vm_page_wire(m);
        vm_page_unlock_queues();

        OSAddAtomic(1,  &inuse_ptepages_count);
        OSAddAtomic64(1,  &alloc_ptepages_count);
        PMAP_ZINFO_PALLOC(PAGE_SIZE);

        /* Take the oject lock (mutex) before the PMAP_LOCK (spinlock) */
        vm_object_lock(map->pm_obj);

        PMAP_LOCK(map);

        /*
         *      See if someone else expanded us first
         */
        if (pmap_pte(map, vaddr) != PT_ENTRY_NULL) {
                PMAP_UNLOCK(map);
                vm_object_unlock(map->pm_obj);

                VM_PAGE_FREE(m);

                OSAddAtomic(-1,  &inuse_ptepages_count);
                PMAP_ZINFO_PFREE(PAGE_SIZE);
                return;
        }

#if 0 /* DEBUG */
       if (0 != vm_page_lookup(map->pm_obj, (vm_object_offset_t)i)) {
               panic("pmap_expand: obj not empty, pmap 0x%x pm_obj 0x%x vaddr 0x%llx i 0x%llx\n",
                     map, map->pm_obj, vaddr, i);
       }
#endif
        vm_page_insert(m, map->pm_obj, (vm_object_offset_t)i);
        vm_object_unlock(map->pm_obj);

        /*
         *      Set the page directory entry for this page table.
         */
        pdp = pmap_pde(map, vaddr);
        pmap_store_pte(pdp, pa_to_pte(pa)
                                | INTEL_PTE_VALID
                                | INTEL_PTE_USER
                                | INTEL_PTE_WRITE);

        PMAP_UNLOCK(map);

        return;
}

/* On K64 machines with more than 32GB of memory, pmap_steal_memory
 * will allocate past the 1GB of pre-expanded virtual kernel area. This
 * function allocates all the page tables using memory from the same pool
 * that pmap_steal_memory uses, rather than calling vm_page_grab (which
 * isn't available yet). */
void
pmap_pre_expand(pmap_t pmap, vm_map_offset_t vaddr)
{
        ppnum_t pn;
        pt_entry_t              *pte;

        PMAP_LOCK(pmap);

        if(pmap64_pdpt(pmap, vaddr) == PDPT_ENTRY_NULL) {
                if (!pmap_next_page_hi(&pn))
                        panic("pmap_pre_expand");

                pmap_zero_page(pn);

                pte = pmap64_pml4(pmap, vaddr);

                pmap_store_pte(pte, pa_to_pte(i386_ptob(pn))
                                | INTEL_PTE_VALID
                                | INTEL_PTE_USER
                                | INTEL_PTE_WRITE);
        }

        if(pmap64_pde(pmap, vaddr) == PD_ENTRY_NULL) {
                if (!pmap_next_page_hi(&pn))
                        panic("pmap_pre_expand");

                pmap_zero_page(pn);

                pte = pmap64_pdpt(pmap, vaddr);

                pmap_store_pte(pte, pa_to_pte(i386_ptob(pn))
                                | INTEL_PTE_VALID
                                | INTEL_PTE_USER
                                | INTEL_PTE_WRITE);
        }

        if(pmap_pte(pmap, vaddr) == PT_ENTRY_NULL) {
                if (!pmap_next_page_hi(&pn))
                        panic("pmap_pre_expand");

                pmap_zero_page(pn);

                pte = pmap64_pde(pmap, vaddr);

                pmap_store_pte(pte, pa_to_pte(i386_ptob(pn))
                                | INTEL_PTE_VALID
                                | INTEL_PTE_USER
                                | INTEL_PTE_WRITE);
        }

        PMAP_UNLOCK(pmap);
}

/*
 * pmap_sync_page_data_phys(ppnum_t pa)
 * 
 * Invalidates all of the instruction cache on a physical page and
 * pushes any dirty data from the data cache for the same physical page
 * Not required in i386.
 */
void
pmap_sync_page_data_phys(__unused ppnum_t pa)
{
        return;
}

/*
 * pmap_sync_page_attributes_phys(ppnum_t pa)
 * 
 * Write back and invalidate all cachelines on a physical page.
 */
void
pmap_sync_page_attributes_phys(ppnum_t pa)
{
        cache_flush_page_phys(pa);
}



#ifdef CURRENTLY_UNUSED_AND_UNTESTED

int     collect_ref;
int     collect_unref;

/*
 *      Routine:        pmap_collect
 *      Function:
 *              Garbage collects the physical map system for
 *              pages which are no longer used.
 *              Success need not be guaranteed -- that is, there
 *              may well be pages which are not referenced, but
 *              others may be collected.
 *      Usage:
 *              Called by the pageout daemon when pages are scarce.
 */
void
pmap_collect(
        pmap_t          p)
{
        register pt_entry_t     *pdp, *ptp;
        pt_entry_t              *eptp;
        int                     wired;

        if (p == PMAP_NULL)
                return;

        if (p == kernel_pmap)
                return;

        /*
         *      Garbage collect map.
         */
        PMAP_LOCK(p);

        for (pdp = (pt_entry_t *)p->dirbase;
             pdp < (pt_entry_t *)&p->dirbase[(UMAXPTDI+1)];
             pdp++)
        {
           if (*pdp & INTEL_PTE_VALID) {
              if(*pdp & INTEL_PTE_REF) {
                pmap_store_pte(pdp, *pdp & ~INTEL_PTE_REF);
                collect_ref++;
              } else {
                collect_unref++;
                ptp = pmap_pte(p, pdetova(pdp - (pt_entry_t *)p->dirbase));
                eptp = ptp + NPTEPG;

                /*
                 * If the pte page has any wired mappings, we cannot
                 * free it.
                 */
                wired = 0;
                {
                    register pt_entry_t *ptep;
                    for (ptep = ptp; ptep < eptp; ptep++) {
                        if (iswired(*ptep)) {
                            wired = 1;
                            break;
                        }
                    }
                }
                if (!wired) {
                    /*
                     * Remove the virtual addresses mapped by this pte page.
                     */
                    pmap_remove_range(p,
                                pdetova(pdp - (pt_entry_t *)p->dirbase),
                                ptp,
                                eptp);

                    /*
                     * Invalidate the page directory pointer.
                     */
                    pmap_store_pte(pdp, 0x0);
                 
                    PMAP_UNLOCK(p);

                    /*
                     * And free the pte page itself.
                     */
                    {
                        register vm_page_t m;

                        vm_object_lock(p->pm_obj);

                        m = vm_page_lookup(p->pm_obj,(vm_object_offset_t)(pdp - (pt_entry_t *)&p->dirbase[0]));
                        if (m == VM_PAGE_NULL)
                            panic("pmap_collect: pte page not in object");

                        vm_object_unlock(p->pm_obj);

                        VM_PAGE_FREE(m);

                        OSAddAtomic(-1,  &inuse_ptepages_count);
                        PMAP_ZINFO_PFREE(PAGE_SIZE);
                    }

                    PMAP_LOCK(p);
                }
              }
           }
        }

        PMAP_UPDATE_TLBS(p, 0x0, 0xFFFFFFFFFFFFF000ULL);
        PMAP_UNLOCK(p);
        return;

}
#endif


void
pmap_copy_page(ppnum_t src, ppnum_t dst)
{
        bcopy_phys((addr64_t)i386_ptob(src),
                   (addr64_t)i386_ptob(dst),
                   PAGE_SIZE);
}


/*
 *      Routine:        pmap_pageable
 *      Function:
 *              Make the specified pages (by pmap, offset)
 *              pageable (or not) as requested.
 *
 *              A page which is not pageable may not take
 *              a fault; therefore, its page table entry
 *              must remain valid for the duration.
 *
 *              This routine is merely advisory; pmap_enter
 *              will specify that these pages are to be wired
 *              down (or not) as appropriate.
 */
void
pmap_pageable(
        __unused pmap_t                 pmap,
        __unused vm_map_offset_t        start_addr,
        __unused vm_map_offset_t        end_addr,
        __unused boolean_t              pageable)
{
#ifdef  lint
        pmap++; start_addr++; end_addr++; pageable++;
#endif  /* lint */
}


void 
invalidate_icache(__unused vm_offset_t  addr,
                  __unused unsigned     cnt,
                  __unused int          phys)
{
        return;
}

void 
flush_dcache(__unused vm_offset_t       addr,
             __unused unsigned          count,
             __unused int               phys)
{
        return;
}

#if CONFIG_DTRACE
/*
 * Constrain DTrace copyin/copyout actions
 */
extern kern_return_t dtrace_copyio_preflight(addr64_t);
extern kern_return_t dtrace_copyio_postflight(addr64_t);

kern_return_t dtrace_copyio_preflight(__unused addr64_t va)
{
        thread_t thread = current_thread();
        uint64_t ccr3;

        if (current_map() == kernel_map)
                return KERN_FAILURE;
        else if (((ccr3 = get_cr3_base()) != thread->map->pmap->pm_cr3) && (no_shared_cr3 == FALSE))
                return KERN_FAILURE;
        else if (no_shared_cr3 && (ccr3 != kernel_pmap->pm_cr3))
                return KERN_FAILURE;
        else if (thread->machine.specFlags & CopyIOActive)
                return KERN_FAILURE;
        else
                return KERN_SUCCESS;
}
 
kern_return_t dtrace_copyio_postflight(__unused addr64_t va)
{
        return KERN_SUCCESS;
}
#endif /* CONFIG_DTRACE */

#include <mach_vm_debug.h>
#if     MACH_VM_DEBUG
#include <vm/vm_debug.h>

int
pmap_list_resident_pages(
        __unused pmap_t         pmap,
        __unused vm_offset_t    *listp,
        __unused int            space)
{
        return 0;
}
#endif  /* MACH_VM_DEBUG */



/* temporary workaround */
boolean_t
coredumpok(__unused vm_map_t map, __unused vm_offset_t va)
{
#if 0
        pt_entry_t     *ptep;

        ptep = pmap_pte(map->pmap, va);
        if (0 == ptep)
                return FALSE;
        return ((*ptep & (INTEL_PTE_NCACHE | INTEL_PTE_WIRED)) != (INTEL_PTE_NCACHE | INTEL_PTE_WIRED));
#else
        return TRUE;
#endif
}


boolean_t
phys_page_exists(ppnum_t pn)
{
        assert(pn != vm_page_fictitious_addr);

        if (!pmap_initialized)
                return TRUE;

        if (pn == vm_page_guard_addr)
                return FALSE;

        if (!IS_MANAGED_PAGE(ppn_to_pai(pn)))
                return FALSE;

        return TRUE;
}



void
pmap_switch(pmap_t tpmap)
{
        spl_t   s;

        s = splhigh();          /* Make sure interruptions are disabled */
        set_dirbase(tpmap, current_thread());
        splx(s);
}


/*
 * disable no-execute capability on
 * the specified pmap
 */
void
pmap_disable_NX(pmap_t pmap)
{
        pmap->nx_enabled = 0;
}

void 
pt_fake_zone_init(int zone_index)
{
        pt_fake_zone_index = zone_index;
}

void
pt_fake_zone_info(
        int             *count,
        vm_size_t       *cur_size,
        vm_size_t       *max_size,
        vm_size_t       *elem_size,
        vm_size_t       *alloc_size,
        uint64_t        *sum_size,
        int             *collectable,
        int             *exhaustable,
        int             *caller_acct)
{
        *count      = inuse_ptepages_count;
        *cur_size   = PAGE_SIZE * inuse_ptepages_count;
        *max_size   = PAGE_SIZE * (inuse_ptepages_count +
                                   vm_page_inactive_count +
                                   vm_page_active_count +
                                   vm_page_free_count);
        *elem_size  = PAGE_SIZE;
        *alloc_size = PAGE_SIZE;
        *sum_size = alloc_ptepages_count * PAGE_SIZE;

        *collectable = 1;
        *exhaustable = 0;
        *caller_acct = 1;
}

static inline void
pmap_cpuset_NMIPI(cpu_set cpu_mask) {
        unsigned int cpu, cpu_bit;
        uint64_t deadline;

        for (cpu = 0, cpu_bit = 1; cpu < real_ncpus; cpu++, cpu_bit <<= 1) {
                if (cpu_mask & cpu_bit)
                        cpu_NMI_interrupt(cpu);
        }
        deadline = mach_absolute_time() + (LockTimeOut);
        while (mach_absolute_time() < deadline)
                cpu_pause();
}

/*
 * Called with pmap locked, we:
 *  - scan through per-cpu data to see which other cpus need to flush
 *  - send an IPI to each non-idle cpu to be flushed
 *  - wait for all to signal back that they are inactive or we see that
 *    they are at a safe point (idle).
 *  - flush the local tlb if active for this pmap
 *  - return ... the caller will unlock the pmap
 */

void
pmap_flush_tlbs(pmap_t  pmap, vm_map_offset_t startv, vm_map_offset_t endv)
{
        unsigned int    cpu;
        unsigned int    cpu_bit;
        cpu_set         cpus_to_signal;
        unsigned int    my_cpu = cpu_number();
        pmap_paddr_t    pmap_cr3 = pmap->pm_cr3;
        boolean_t       flush_self = FALSE;
        uint64_t        deadline;
        boolean_t       pmap_is_shared = (pmap->pm_shared || (pmap == kernel_pmap));

        assert((processor_avail_count < 2) ||
               (ml_get_interrupts_enabled() && get_preemption_level() != 0));

        /*
         * Scan other cpus for matching active or task CR3.
         * For idle cpus (with no active map) we mark them invalid but
         * don't signal -- they'll check as they go busy.
         */
        cpus_to_signal = 0;

        if (pmap_pcid_ncpus) {
                pmap_pcid_invalidate_all_cpus(pmap);
                __asm__ volatile("mfence":::"memory");
        }

        for (cpu = 0, cpu_bit = 1; cpu < real_ncpus; cpu++, cpu_bit <<= 1) {
                if (!cpu_datap(cpu)->cpu_running)
                        continue;
                uint64_t        cpu_active_cr3 = CPU_GET_ACTIVE_CR3(cpu);
                uint64_t        cpu_task_cr3 = CPU_GET_TASK_CR3(cpu);

                if ((pmap_cr3 == cpu_task_cr3) ||
                    (pmap_cr3 == cpu_active_cr3) ||
                    (pmap_is_shared)) {
                        if (cpu == my_cpu) {
                                flush_self = TRUE;
                                continue;
                        }
                        if (pmap_pcid_ncpus && pmap_is_shared)
                                cpu_datap(cpu)->cpu_tlb_invalid_global = TRUE;
                        else
                                cpu_datap(cpu)->cpu_tlb_invalid_local = TRUE;
                        __asm__ volatile("mfence":::"memory");

                        /*
                         * We don't need to signal processors which will flush
                         * lazily at the idle state or kernel boundary.
                         * For example, if we're invalidating the kernel pmap,
                         * processors currently in userspace don't need to flush
                         * their TLBs until the next time they enter the kernel.
                         * Alterations to the address space of a task active
                         * on a remote processor result in a signal, to
                         * account for copy operations. (There may be room
                         * for optimization in such cases).
                         * The order of the loads below with respect
                         * to the store to the "cpu_tlb_invalid" field above
                         * is important--hence the barrier.
                         */
                        if (CPU_CR3_IS_ACTIVE(cpu) &&
                            (pmap_cr3 == CPU_GET_ACTIVE_CR3(cpu) ||
                            pmap->pm_shared ||
                            (pmap_cr3 == CPU_GET_TASK_CR3(cpu)))) {
                                cpus_to_signal |= cpu_bit;
                                i386_signal_cpu(cpu, MP_TLB_FLUSH, ASYNC);
                        }
                }
        }

        PMAP_TRACE_CONSTANT(PMAP_CODE(PMAP__FLUSH_TLBS) | DBG_FUNC_START,
                   pmap, cpus_to_signal, flush_self, startv, endv);

        /*
         * Flush local tlb if required.
         * Do this now to overlap with other processors responding.
         */
        if (flush_self) {
                if (pmap_pcid_ncpus) {
                        pmap_pcid_validate_cpu(pmap, my_cpu);
                        if (pmap_is_shared)
                                tlb_flush_global();
                        else
                                flush_tlb_raw();
                }
                else
                        flush_tlb_raw();
        }

        if (cpus_to_signal) {
                cpu_set cpus_to_respond = cpus_to_signal;

                deadline = mach_absolute_time() + LockTimeOut;
                /*
                 * Wait for those other cpus to acknowledge
                 */
                while (cpus_to_respond != 0) {
                        long orig_acks = 0;

                        for (cpu = 0, cpu_bit = 1; cpu < real_ncpus; cpu++, cpu_bit <<= 1) {
                                /* Consider checking local/global invalidity
                                 * as appropriate in the PCID case.
                                 */
                                if ((cpus_to_respond & cpu_bit) != 0) {
                                        if (!cpu_datap(cpu)->cpu_running ||
                                            cpu_datap(cpu)->cpu_tlb_invalid == FALSE ||
                                            !CPU_CR3_IS_ACTIVE(cpu)) {
                                                cpus_to_respond &= ~cpu_bit;
                                        }
                                        cpu_pause();
                                }
                                if (cpus_to_respond == 0)
                                        break;
                        }
                        if (cpus_to_respond && (mach_absolute_time() > deadline)) {
                                if (machine_timeout_suspended())
                                        continue;
                                pmap_tlb_flush_timeout = TRUE;
                                orig_acks = NMIPI_acks;
                                pmap_cpuset_NMIPI(cpus_to_respond);

                                panic("TLB invalidation IPI timeout: "
                                    "CPU(s) failed to respond to interrupts, unresponsive CPU bitmap: 0x%lx, NMIPI acks: orig: 0x%lx, now: 0x%lx",
                                    cpus_to_respond, orig_acks, NMIPI_acks);
                        }
                }
        }

        PMAP_TRACE_CONSTANT(PMAP_CODE(PMAP__FLUSH_TLBS) | DBG_FUNC_END,
            pmap, cpus_to_signal, startv, endv, 0);
}

void
process_pmap_updates(void)
{
        int ccpu = cpu_number();
        pmap_assert(ml_get_interrupts_enabled() == 0 || get_preemption_level() != 0);
        if (pmap_pcid_ncpus) {
                pmap_pcid_validate_current();
                if (cpu_datap(ccpu)->cpu_tlb_invalid_global) {
                        cpu_datap(ccpu)->cpu_tlb_invalid = FALSE;
                        tlb_flush_global();
                }
                else {
                        cpu_datap(ccpu)->cpu_tlb_invalid_local = FALSE;
                        flush_tlb_raw();
                }
        }
        else {
                current_cpu_datap()->cpu_tlb_invalid = FALSE;
                flush_tlb_raw();
        }

        __asm__ volatile("mfence");
}

void
pmap_update_interrupt(void)
{
        PMAP_TRACE(PMAP_CODE(PMAP__UPDATE_INTERRUPT) | DBG_FUNC_START,
                   0, 0, 0, 0, 0);

        process_pmap_updates();

        PMAP_TRACE(PMAP_CODE(PMAP__UPDATE_INTERRUPT) | DBG_FUNC_END,
                   0, 0, 0, 0, 0);
}