hat_i86.c revision b193e412a0fb5b3759d2d7921eb9ed83d4d9b077
/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License, Version 1.0 only
* (the "License"). You may not use this file except in compliance
* with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or http://www.opensolaris.org/os/licensing.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/*
* Copyright 2005 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
#pragma ident "%Z%%M% %I% %E% SMI"
/*
* VM - Hardware Address Translation management for i386 and amd64
*
* Implementation of the interfaces described in <common/vm/hat.h>
*
* Nearly all the details of how the hardware is managed should not be
* visible outside this layer except for misc. machine specific functions
* that work in conjunction with this code.
*
* Routines used only inside of i86pc/vm start with hati_ for HAT Internal.
*/
#include <sys/machparam.h>
#include <sys/machsystm.h>
#include <sys/mman.h>
#include <sys/types.h>
#include <sys/systm.h>
#include <sys/cpuvar.h>
#include <sys/thread.h>
#include <sys/proc.h>
#include <sys/cpu.h>
#include <sys/kmem.h>
#include <sys/disp.h>
#include <sys/shm.h>
#include <sys/sysmacros.h>
#include <sys/machparam.h>
#include <sys/vmem.h>
#include <sys/vmsystm.h>
#include <sys/promif.h>
#include <sys/var.h>
#include <sys/x86_archext.h>
#include <sys/atomic.h>
#include <sys/bitmap.h>
#include <vm/seg_kmem.h>
#include <vm/hat_i86.h>
#include <vm/as.h>
#include <vm/seg.h>
#include <vm/page.h>
#include <vm/seg_kp.h>
#include <vm/seg_kpm.h>
#include <vm/vm_dep.h>
#include <sys/cmn_err.h>
/*
* Basic parameters for hat operation.
*/
struct hat_mmu_info mmu;
uint_t force_pae_off = 0; /* for testing, change with kernel debugger */
uint_t force_pae_on = 0; /* for testing, change with kernel debugger */
/*
* The page that is the kernel's top level pagetable.
*
* For 32 bit VLP support, the kernel hat will use the 1st 4 entries
* on this 4K page for its top level page table. The remaining groups of
* 4 entries are used for per processor copies of user VLP pagetables for
* running threads. See hat_switch() and reload_pae32() for details.
*
* vlp_page[0] - 0th level==2 PTE for kernel HAT (will be zero)
* vlp_page[1] - 1st level==2 PTE for kernel HAT (will be zero)
* vlp_page[2] - 2nd level==2 PTE for kernel HAT (zero for small memory)
* vlp_page[3] - 3rd level==2 PTE for kernel
*
* vlp_page[4] - 0th level==2 PTE for user thread on cpu 0
* vlp_page[5] - 1st level==2 PTE for user thread on cpu 0
* vlp_page[6] - 2nd level==2 PTE for user thread on cpu 0
* vlp_page[7] - probably copy of kernel PTE
*
* vlp_page[8] - 0th level==2 PTE for user thread on cpu 1
* vlp_page[9] - 1st level==2 PTE for user thread on cpu 1
* vlp_page[10] - 2nd level==2 PTE for user thread on cpu 1
* vlp_page[11] - probably copy of kernel PTE
* ...
*
* when / where the kernel PTE's are (entry 2 or 3 or none) depends
* on kernelbase.
*/
static x86pte_t *vlp_page;
/*
* forward declaration of internal utility routines
*/
static x86pte_t hati_update_pte(htable_t *ht, uint_t entry, x86pte_t expected,
x86pte_t new);
/*
* The kernel address space exists in all HATs. To implement this the
* kernel reserves a fixed number of entries in every topmost level page
* table. The values are setup in hat_init() and then copied to every hat
* created by hat_alloc(). This means that kernelbase must be:
*
* 4Meg aligned for 32 bit kernels
* 512Gig aligned for x86_64 64 bit kernel
*
* The PAE 32 bit hat is handled as a special case. Otherwise requiring 1Gig
* alignment would use too much VA for the kernel.
*
*/
static uint_t khat_start; /* index of 1st entry in kernel's top ptable */
static uint_t khat_entries; /* number of entries in kernel's top ptable */
#if defined(__i386)
static htable_t *khat_pae32_htable = NULL;
static uint_t khat_pae32_start;
static uint_t khat_pae32_entries;
#endif
/*
* Locks, etc. to control use of the hat reserves when recursively
* allocating pagetables for the hat data structures.
*/
static kmutex_t hat_reserves_lock;
static kcondvar_t hat_reserves_cv;
kthread_t *hat_reserves_thread;
uint_t use_boot_reserve = 1; /* cleared after early boot process */
uint_t can_steal_post_boot = 0; /* set late in boot to enable stealing */
/*
* A cpuset for all cpus. This is used for kernel address cross calls, since
* the kernel addresses apply to all cpus.
*/
cpuset_t khat_cpuset;
/*
* management stuff for hat structures
*/
kmutex_t hat_list_lock;
kcondvar_t hat_list_cv;
kmem_cache_t *hat_cache;
kmem_cache_t *hat_hash_cache;
kmem_cache_t *vlp_hash_cache;
/*
* Simple statistics
*/
struct hatstats hatstat;
/*
* macros to detect addresses in use by kernel only during boot
*/
#if defined(__amd64)
#define BOOT_VA(va) ((va) < kernelbase || \
((va) >= BOOT_DOUBLEMAP_BASE && \
(va) < BOOT_DOUBLEMAP_BASE + BOOT_DOUBLEMAP_SIZE))
#elif defined(__i386)
#define BOOT_VA(va) ((va) < kernelbase)
#endif /* __i386 */
/*
* useful stuff for atomic access/clearing/setting REF/MOD/RO bits in page_t's.
*/
extern void atomic_orb(uchar_t *addr, uchar_t val);
extern void atomic_andb(uchar_t *addr, uchar_t val);
#define PP_GETRM(pp, rmmask) (pp->p_nrm & rmmask)
#define PP_ISMOD(pp) PP_GETRM(pp, P_MOD)
#define PP_ISREF(pp) PP_GETRM(pp, P_REF)
#define PP_ISRO(pp) PP_GETRM(pp, P_RO)
#define PP_SETRM(pp, rm) atomic_orb(&(pp->p_nrm), rm)
#define PP_SETMOD(pp) PP_SETRM(pp, P_MOD)
#define PP_SETREF(pp) PP_SETRM(pp, P_REF)
#define PP_SETRO(pp) PP_SETRM(pp, P_RO)
#define PP_CLRRM(pp, rm) atomic_andb(&(pp->p_nrm), ~(rm))
#define PP_CLRMOD(pp) PP_CLRRM(pp, P_MOD)
#define PP_CLRREF(pp) PP_CLRRM(pp, P_REF)
#define PP_CLRRO(pp) PP_CLRRM(pp, P_RO)
#define PP_CLRALL(pp) PP_CLRRM(pp, P_MOD | P_REF | P_RO)
/*
* some useful tracing macros
*/
int hattrace = 0;
#ifdef DEBUG
#define HATIN(r, h, a, l) \
if (hattrace) prom_printf("->%s hat=%p, adr=%p, len=%lx\n", #r, h, a, l)
#define HATOUT(r, h, a) \
if (hattrace) prom_printf("<-%s hat=%p, adr=%p\n", #r, h, a)
#else
#define HATIN(r, h, a, l)
#define HATOUT(r, h, a)
#endif
/*
* kmem cache constructor for struct hat
*/
/*ARGSUSED*/
static int
hati_constructor(void *buf, void *handle, int kmflags)
{
hat_t *hat = buf;
mutex_init(&hat->hat_mutex, NULL, MUTEX_DEFAULT, NULL);
bzero(hat->hat_pages_mapped,
sizeof (pgcnt_t) * (mmu.max_page_level + 1));
hat->hat_stats = 0;
hat->hat_flags = 0;
mutex_init(&hat->hat_switch_mutex, NULL, MUTEX_DRIVER,
(void *)ipltospl(DISP_LEVEL));
CPUSET_ZERO(hat->hat_cpus);
hat->hat_htable = NULL;
hat->hat_ht_hash = NULL;
return (0);
}
/*
* Allocate a hat structure for as. We also create the top level
* htable and initialize it to contain the kernel hat entries.
*/
hat_t *
hat_alloc(struct as *as)
{
hat_t *hat;
htable_t *ht; /* top level htable */
uint_t use_vlp;
/*
* Once we start creating user process HATs we can enable
* the htable_steal() code.
*/
if (can_steal_post_boot == 0)
can_steal_post_boot = 1;
ASSERT(AS_WRITE_HELD(as, &as->a_lock));
hat = kmem_cache_alloc(hat_cache, KM_SLEEP);
hat->hat_as = as;
mutex_init(&hat->hat_mutex, NULL, MUTEX_DEFAULT, NULL);
ASSERT(hat->hat_flags == 0);
/*
* a 32 bit process uses a VLP style hat when using PAE
*/
#if defined(__amd64)
use_vlp = (ttoproc(curthread)->p_model == DATAMODEL_ILP32);
#elif defined(__i386)
use_vlp = mmu.pae_hat;
#endif
if (use_vlp) {
hat->hat_flags = HAT_VLP;
bzero(hat->hat_vlp_ptes, VLP_SIZE);
}
/*
* Allocate the htable hash
*/
if ((hat->hat_flags & HAT_VLP)) {
hat->hat_num_hash = mmu.vlp_hash_cnt;
hat->hat_ht_hash = kmem_cache_alloc(vlp_hash_cache, KM_SLEEP);
} else {
hat->hat_num_hash = mmu.hash_cnt;
hat->hat_ht_hash = kmem_cache_alloc(hat_hash_cache, KM_SLEEP);
}
bzero(hat->hat_ht_hash, hat->hat_num_hash * sizeof (htable_t *));
/*
* Initialize Kernel HAT entries at the top of the top level page
* table for the new hat.
*
* Note that we don't call htable_release() for the top level, that
* happens when the hat is destroyed in hat_free_end()
*/
hat->hat_htable = NULL;
hat->hat_ht_cached = NULL;
ht = htable_create(hat, (uintptr_t)0, TOP_LEVEL(hat), NULL);
if (!(hat->hat_flags & HAT_VLP))
x86pte_copy(kas.a_hat->hat_htable, ht, khat_start,
khat_entries);
#if defined(__i386)
else if (khat_entries > 0)
bcopy(vlp_page + khat_start, hat->hat_vlp_ptes + khat_start,
khat_entries * sizeof (x86pte_t));
#endif
hat->hat_htable = ht;
#if defined(__i386)
/*
* PAE32 HAT alignment is less restrictive than the others to keep
* the kernel from using too much VA. Because of this we may need
* one layer further down when kernelbase isn't 1Gig aligned.
* See hat_free_end() for the htable_release() that goes with this
* htable_create()
*/
if (khat_pae32_htable != NULL) {
ht = htable_create(hat, kernelbase,
khat_pae32_htable->ht_level, NULL);
x86pte_copy(khat_pae32_htable, ht, khat_pae32_start,
khat_pae32_entries);
ht->ht_valid_cnt = khat_pae32_entries;
}
#endif
/*
* Put it in the global list of all hats (used by stealing, etc.)
*/
mutex_enter(&hat_list_lock);
if (kas.a_hat->hat_next != NULL) {
hat->hat_next = kas.a_hat->hat_next;
hat->hat_prev = kas.a_hat->hat_next->hat_prev;
kas.a_hat->hat_next->hat_prev->hat_next = hat;
kas.a_hat->hat_next->hat_prev = hat;
} else {
hat->hat_next = hat;
hat->hat_prev = hat;
}
kas.a_hat->hat_next = hat;
mutex_exit(&hat_list_lock);
return (hat);
}
/*
* process has finished executing but as has not been cleaned up yet.
*/
/*ARGSUSED*/
void
hat_free_start(hat_t *hat)
{
ASSERT(AS_WRITE_HELD(hat->hat_as, &hat->hat_as->a_lock));
mutex_enter(&hat_list_lock);
hat->hat_flags |= HAT_FREEING;
mutex_exit(&hat_list_lock);
}
/*
* An address space is being destroyed, so we destroy the associated hat.
*/
void
hat_free_end(hat_t *hat)
{
int i;
kmem_cache_t *cache;
#ifdef DEBUG
for (i = 0; i <= mmu.max_page_level; i++)
ASSERT(hat->hat_pages_mapped[i] == 0);
#endif
ASSERT(hat->hat_flags & HAT_FREEING);
/*
* must not be running on the given hat
*/
ASSERT(CPU->cpu_current_hat != hat);
/*
* If the hat is currently a stealing victim, wait for the stealing
* to finish. Once we've removed it from the list, nobody can
* find these htables anymore.
*/
mutex_enter(&hat_list_lock);
while (hat->hat_flags & HAT_VICTIM)
cv_wait(&hat_list_cv, &hat_list_lock);
hat->hat_next->hat_prev = hat->hat_prev;
hat->hat_prev->hat_next = hat->hat_next;
if (kas.a_hat->hat_next == hat) {
kas.a_hat->hat_next = hat->hat_next;
if (kas.a_hat->hat_next == hat)
kas.a_hat->hat_next = NULL;
}
mutex_exit(&hat_list_lock);
/*
* Make a pass through the htables freeing them all up.
*/
htable_purge_hat(hat);
/*
* Decide which kmem cache the hash table came from, then free it.
*/
if (hat->hat_flags & HAT_VLP)
cache = vlp_hash_cache;
else
cache = hat_hash_cache;
kmem_cache_free(cache, hat->hat_ht_hash);
hat->hat_ht_hash = NULL;
hat->hat_flags = 0;
kmem_cache_free(hat_cache, hat);
}
/*
* round kernelbase down to a supported value to use for _userlimit
*
* userlimit must be aligned down to an entry in the top level htable.
* The one exception is for 32 bit HAT's running PAE.
*/
uintptr_t
hat_kernelbase(uintptr_t va)
{
#if defined(__i386)
va &= LEVEL_MASK(1);
#endif
if (IN_VA_HOLE(va))
panic("_userlimit %p will fall in VA hole\n", (void *)va);
return (va);
}
/*
* Initialize hat data structures based on processor MMU information.
*/
void
mmu_init(void)
{
uint_t max_htables;
uint_t pa_bits;
uint_t va_bits;
int i;
/*
* if CPU enabled the page table global bit, use it for the kernel
* This is bit 7 in CR4 (PGE - Page Global Enable)
*/
if ((x86_feature & X86_PGE) != 0 && (getcr4() & 0x80) != 0)
mmu.pt_global = PT_GLOBAL;
/*
* We use PAE except when we aren't on an AMD64 and this is
* a 32 bit kernel with all physical addresses less than 4 Gig.
*/
mmu.pae_hat = 1;
if (x86_feature & X86_NX) {
mmu.pt_nx = PT_NX;
} else {
mmu.pt_nx = 0;
#if defined(__i386)
if (!PFN_ABOVE4G(physmax))
mmu.pae_hat = 0;
#endif
}
#if defined(__i386)
/*
* Setting one of these two lets you force testing of the different
* hat modes for 32 bit, regardless of the hardware setup.
*/
if (force_pae_on) {
mmu.pae_hat = 1;
} else if (force_pae_off) {
mmu.pae_hat = 0;
mmu.pt_nx = 0;
}
#endif
/*
* Use CPU info to set various MMU parameters
*/
cpuid_get_addrsize(CPU, &pa_bits, &va_bits);
if (va_bits < sizeof (void *) * NBBY) {
mmu.hole_start = (1ul << (va_bits - 1));
mmu.hole_end = 0ul - mmu.hole_start - 1;
} else {
mmu.hole_end = 0;
mmu.hole_start = mmu.hole_end - 1;
}
#if defined(OPTERON_ERRATUM_121)
/*
* If erratum 121 has already been detected at this time, hole_start
* contains the value to be subtracted from mmu.hole_start.
*/
ASSERT(hole_start == 0 || opteron_erratum_121 != 0);
hole_start = mmu.hole_start - hole_start;
#else
hole_start = mmu.hole_start;
#endif
hole_end = mmu.hole_end;
mmu.highest_pfn = mmu_btop((1ull << pa_bits) - 1);
if (mmu.pae_hat == 0 && pa_bits > 32)
mmu.highest_pfn = PFN_4G - 1;
if (mmu.pae_hat) {
mmu.pte_size = 8; /* 8 byte PTEs */
mmu.pte_size_shift = 3;
} else {
mmu.pte_size = 4; /* 4 byte PTEs */
mmu.pte_size_shift = 2;
}
if (mmu.pae_hat && (x86_feature & X86_PAE) == 0)
panic("Processor does not support PAE");
if ((x86_feature & X86_CX8) == 0)
panic("Processor does not support cmpxchg8b instruction");
/*
* Initialize parameters based on the 64 or 32 bit kernels and
* for the 32 bit kernel decide if we should use PAE.
*/
if (x86_feature & X86_LARGEPAGE)
mmu.max_page_level = 1;
else
mmu.max_page_level = 0;
mmu_page_sizes = mmu.max_page_level + 1;
mmu_exported_page_sizes = mmu_page_sizes;
#if defined(__amd64)
mmu.num_level = 4;
mmu.max_level = 3;
mmu.ptes_per_table = 512;
mmu.top_level_count = 512;
mmu.level_shift[0] = 12;
mmu.level_shift[1] = 21;
mmu.level_shift[2] = 30;
mmu.level_shift[3] = 39;
#elif defined(__i386)
if (mmu.pae_hat) {
mmu.num_level = 3;
mmu.max_level = 2;
mmu.ptes_per_table = 512;
mmu.top_level_count = 4;
mmu.level_shift[0] = 12;
mmu.level_shift[1] = 21;
mmu.level_shift[2] = 30;
} else {
mmu.num_level = 2;
mmu.max_level = 1;
mmu.ptes_per_table = 1024;
mmu.top_level_count = 1024;
mmu.level_shift[0] = 12;
mmu.level_shift[1] = 22;
}
#endif /* __i386 */
for (i = 0; i < mmu.num_level; ++i) {
mmu.level_size[i] = 1UL << mmu.level_shift[i];
mmu.level_offset[i] = mmu.level_size[i] - 1;
mmu.level_mask[i] = ~mmu.level_offset[i];
}
mmu.pte_bits[0] = PT_VALID;
for (i = 1; i <= mmu.max_page_level; ++i)
mmu.pte_bits[i] = PT_VALID | PT_PAGESIZE;
/*
* NOTE Legacy 32 bit PAE mode only has the P_VALID bit at top level.
*/
for (i = 1; i < mmu.num_level; ++i)
mmu.ptp_bits[i] = PT_PTPBITS;
#if defined(__i386)
mmu.ptp_bits[2] = PT_VALID;
#endif
/*
* Compute how many hash table entries to have per process for htables.
* We start with 1 page's worth of entries.
*
* If physical memory is small, reduce the amount need to cover it.
*/
max_htables = physmax / mmu.ptes_per_table;
mmu.hash_cnt = MMU_PAGESIZE / sizeof (htable_t *);
while (mmu.hash_cnt > 16 && mmu.hash_cnt >= max_htables)
mmu.hash_cnt >>= 1;
mmu.vlp_hash_cnt = mmu.hash_cnt;
#if defined(__amd64)
/*
* If running in 64 bits and physical memory is large,
* increase the size of the cache to cover all of memory for
* a 64 bit process.
*/
#define HASH_MAX_LENGTH 4
while (mmu.hash_cnt * HASH_MAX_LENGTH < max_htables)
mmu.hash_cnt <<= 1;
#endif
/*
* This code knows that there are only 2 pagesizes.
* We ignore 4MB (non-PAE) for now. The value is only used
* for optimizing demaps across large ranges.
* These return zero if no information is known.
*/
mmu.tlb_entries[0] = cpuid_get_dtlb_nent(NULL, MMU_PAGESIZE);
mmu.tlb_entries[1] = cpuid_get_dtlb_nent(NULL, 2 * 1024 * 1024);
}
/*
* initialize hat data structures
*/
void
hat_init()
{
#if defined(__i386)
/*
* _userlimit must be aligned correctly
*/
if ((_userlimit & LEVEL_MASK(1)) != _userlimit) {
prom_printf("hat_init(): _userlimit=%p, not aligned at %p\n",
(void *)_userlimit, (void *)LEVEL_SIZE(1));
halt("hat_init(): Unable to continue");
}
#endif
cv_init(&hat_list_cv, NULL, CV_DEFAULT, NULL);
/*
* initialize kmem caches
*/
htable_init();
hment_init();
hat_cache = kmem_cache_create("hat_t",
sizeof (hat_t), 0, hati_constructor, NULL, NULL,
NULL, 0, 0);
hat_hash_cache = kmem_cache_create("HatHash",
mmu.hash_cnt * sizeof (htable_t *), 0, NULL, NULL, NULL,
NULL, 0, 0);
/*
* VLP hats can use a smaller hash table size on large memroy machines
*/
if (mmu.hash_cnt == mmu.vlp_hash_cnt) {
vlp_hash_cache = hat_hash_cache;
} else {
vlp_hash_cache = kmem_cache_create("HatVlpHash",
mmu.vlp_hash_cnt * sizeof (htable_t *), 0, NULL, NULL, NULL,
NULL, 0, 0);
}
/*
* Set up the kernel's hat
*/
AS_LOCK_ENTER(&kas, &kas.a_lock, RW_WRITER);
kas.a_hat = kmem_cache_alloc(hat_cache, KM_NOSLEEP);
mutex_init(&kas.a_hat->hat_mutex, NULL, MUTEX_DEFAULT, NULL);
kas.a_hat->hat_as = &kas;
kas.a_hat->hat_flags = 0;
AS_LOCK_EXIT(&kas, &kas.a_lock);
CPUSET_ZERO(khat_cpuset);
CPUSET_ADD(khat_cpuset, CPU->cpu_id);
/*
* The kernel hat's next pointer serves as the head of the hat list .
*/
kas.a_hat->hat_next = NULL;
/*
* Allocate an htable hash bucket for the kernel
* XX64 - tune for 64 bit procs
*/
kas.a_hat->hat_num_hash = mmu.hash_cnt;
kas.a_hat->hat_ht_hash = kmem_cache_alloc(hat_hash_cache, KM_NOSLEEP);
bzero(kas.a_hat->hat_ht_hash, mmu.hash_cnt * sizeof (htable_t *));
/*
* zero out the top level and cached htable pointers
*/
kas.a_hat->hat_ht_cached = NULL;
kas.a_hat->hat_htable = NULL;
}
/*
* Prepare CPU specific pagetables for VLP processes on 64 bit kernels.
*
* Each CPU has a set of 2 pagetables that are reused for any 32 bit
* process it runs. They are the top level pagetable, hci_vlp_l3ptes, and
* the next to top level table for the bottom 512 Gig, hci_vlp_l2ptes.
*/
/*ARGSUSED*/
static void
hat_vlp_setup(struct cpu *cpu)
{
#if defined(__amd64)
struct hat_cpu_info *hci = cpu->cpu_hat_info;
pfn_t pfn;
/*
* allocate the level==2 page table for the bottom most
* 512Gig of address space (this is where 32 bit apps live)
*/
ASSERT(hci != NULL);
hci->hci_vlp_l2ptes = kmem_zalloc(MMU_PAGESIZE, KM_SLEEP);
/*
* Allocate a top level pagetable and copy the kernel's
* entries into it. Then link in hci_vlp_l2ptes in the 1st entry.
*/
hci->hci_vlp_l3ptes = kmem_zalloc(MMU_PAGESIZE, KM_SLEEP);
hci->hci_vlp_pfn =
hat_getpfnum(kas.a_hat, (caddr_t)hci->hci_vlp_l3ptes);
ASSERT(hci->hci_vlp_pfn != PFN_INVALID);
bcopy(vlp_page + khat_start, hci->hci_vlp_l3ptes + khat_start,
khat_entries * sizeof (x86pte_t));
pfn = hat_getpfnum(kas.a_hat, (caddr_t)hci->hci_vlp_l2ptes);
ASSERT(pfn != PFN_INVALID);
hci->hci_vlp_l3ptes[0] = MAKEPTP(pfn, 2);
#endif /* __amd64 */
}
/*
* Finish filling in the kernel hat.
* Pre fill in all top level kernel page table entries for the kernel's
* part of the address range. From this point on we can't use any new
* kernel large pages if they need PTE's at max_level
*/
void
hat_init_finish(void)
{
htable_t *top = kas.a_hat->hat_htable;
htable_t *ht;
uint_t e;
x86pte_t pte;
uintptr_t va = kernelbase;
#if defined(__i386)
ASSERT((va & LEVEL_MASK(1)) == va);
/*
* Deal with kernelbase not 1Gig aligned for 32 bit PAE hats.
*/
if (!mmu.pae_hat || (va & LEVEL_OFFSET(mmu.max_level)) == 0) {
khat_pae32_htable = NULL;
} else {
ASSERT(mmu.max_level == 2);
ASSERT((va & LEVEL_OFFSET(mmu.max_level - 1)) == 0);
khat_pae32_htable =
htable_create(kas.a_hat, va, mmu.max_level - 1, NULL);
khat_pae32_start = htable_va2entry(va, khat_pae32_htable);
khat_pae32_entries = mmu.ptes_per_table - khat_pae32_start;
for (e = khat_pae32_start; e < mmu.ptes_per_table;
++e, va += LEVEL_SIZE(mmu.max_level - 1)) {
pte = x86pte_get(khat_pae32_htable, e);
if (PTE_ISVALID(pte))
continue;
ht = htable_create(kas.a_hat, va, mmu.max_level - 2,
NULL);
ASSERT(ht != NULL);
}
}
#endif
/*
* The kernel hat will need fixed values in the highest level
* ptable for copying to all other hat's. This implies
* alignment restrictions on _userlimit.
*
* Note we don't htable_release() these htables. This keeps them
* from ever being stolen or free'd.
*
* top_level_count is used instead of ptes_per_table, since
* on 32-bit PAE we only have 4 usable entries at the top level ptable.
*/
if (va == 0)
khat_start = mmu.top_level_count;
else
khat_start = htable_va2entry(va, kas.a_hat->hat_htable);
khat_entries = mmu.top_level_count - khat_start;
for (e = khat_start; e < mmu.top_level_count;
++e, va += LEVEL_SIZE(mmu.max_level)) {
pte = x86pte_get(top, e);
if (PTE_ISVALID(pte))
continue;
ht = htable_create(kas.a_hat, va, mmu.max_level - 1, NULL);
ASSERT(ht != NULL);
}
/*
* We are now effectively running on the kernel hat.
* Clearing use_boot_reserve shuts off using the pre-allocated boot
* reserve for all HAT allocations. From here on, the reserves are
* only used when mapping in memory for the hat's own allocations.
*/
use_boot_reserve = 0;
htable_adjust_reserve();
/*
* 32 bit kernels use only 4 of the 512 entries in its top level
* pagetable. We'll use the remainder for the "per CPU" page tables
* for VLP processes.
*
* We map the top level kernel pagetable into the kernel's AS to make
* it easy to use bcopy for kernel entry PTEs.
*
* We were guaranteed to get a physical address < 4Gig, since the 32 bit
* boot loader uses non-PAE page tables.
*/
if (mmu.pae_hat) {
vlp_page = vmem_alloc(heap_arena, MMU_PAGESIZE, VM_SLEEP);
hat_devload(kas.a_hat, (caddr_t)vlp_page, MMU_PAGESIZE,
kas.a_hat->hat_htable->ht_pfn,
PROT_READ | PROT_WRITE | HAT_NOSYNC | HAT_UNORDERED_OK,
HAT_LOAD | HAT_LOAD_NOCONSIST);
}
hat_vlp_setup(CPU);
}
/*
* On 32 bit PAE mode, PTE's are 64 bits, but ordinary atomic memory references
* are 32 bit, so for safety we must use cas64() to install these.
*/
#ifdef __i386
static void
reload_pae32(hat_t *hat, cpu_t *cpu)
{
x86pte_t *src;
x86pte_t *dest;
x86pte_t pte;
int i;
/*
* Load the 4 entries of the level 2 page table into this
* cpu's range of the vlp_page and point cr3 at them.
*/
ASSERT(mmu.pae_hat);
src = hat->hat_vlp_ptes;
dest = vlp_page + (cpu->cpu_id + 1) * VLP_NUM_PTES;
for (i = 0; i < VLP_NUM_PTES; ++i) {
for (;;) {
pte = dest[i];
if (pte == src[i])
break;
if (cas64(dest + i, pte, src[i]) != src[i])
break;
}
}
}
#endif
/*
* Switch to a new active hat, maintaining bit masks to track active CPUs.
*/
void
hat_switch(hat_t *hat)
{
uintptr_t newcr3;
cpu_t *cpu = CPU;
hat_t *old = cpu->cpu_current_hat;
/*
* set up this information first, so we don't miss any cross calls
*/
if (old != NULL) {
if (old == hat)
return;
if (old != kas.a_hat)
CPUSET_ATOMIC_DEL(old->hat_cpus, cpu->cpu_id);
}
/*
* Wait for any in flight pagetable invalidates on this hat to finish.
* This is a spin lock at DISP_LEVEL
*/
if (hat != kas.a_hat) {
mutex_enter(&hat->hat_switch_mutex);
CPUSET_ATOMIC_ADD(hat->hat_cpus, cpu->cpu_id);
mutex_exit(&hat->hat_switch_mutex);
}
cpu->cpu_current_hat = hat;
/*
* now go ahead and load cr3
*/
if (hat->hat_flags & HAT_VLP) {
#if defined(__amd64)
x86pte_t *vlpptep = cpu->cpu_hat_info->hci_vlp_l2ptes;
VLP_COPY(hat->hat_vlp_ptes, vlpptep);
newcr3 = MAKECR3(cpu->cpu_hat_info->hci_vlp_pfn);
#elif defined(__i386)
reload_pae32(hat, cpu);
newcr3 = MAKECR3(kas.a_hat->hat_htable->ht_pfn) +
(cpu->cpu_id + 1) * VLP_SIZE;
#endif
} else {
newcr3 = MAKECR3(hat->hat_htable->ht_pfn);
}
setcr3(newcr3);
ASSERT(cpu == CPU);
}
/*
* Utility to return a valid x86pte_t from protections, pfn, and level number
*/
static x86pte_t
hati_mkpte(pfn_t pfn, uint_t attr, level_t level, uint_t flags)
{
x86pte_t pte;
uint_t cache_attr = attr & HAT_ORDER_MASK;
pte = MAKEPTE(pfn, level);
if (attr & PROT_WRITE)
PTE_SET(pte, PT_WRITABLE);
if (attr & PROT_USER)
PTE_SET(pte, PT_USER);
if (!(attr & PROT_EXEC))
PTE_SET(pte, mmu.pt_nx);
/*
* set the software bits used track ref/mod sync's and hments
*/
if (attr & HAT_NOSYNC)
PTE_SET(pte, PT_NOSYNC);
if (flags & HAT_LOAD_NOCONSIST)
PTE_SET(pte, PT_NOCONSIST | PT_NOSYNC);
/*
* Set the caching attributes in the PTE. The combination
* of attributes are poorly defined, so we pay attention
* to them in the given order.
*
* The test for HAT_STRICTORDER is different because it's defined
* as "0" - which was a stupid thing to do, but is too late to change!
*/
if (cache_attr == HAT_STRICTORDER) {
PTE_SET(pte, PT_NOCACHE);
/*LINTED [Lint hates empty ifs, but it's the obvious way to do this] */
} else if (cache_attr & (HAT_UNORDERED_OK | HAT_STORECACHING_OK)) {
/* nothing to set */;
} else if (cache_attr & (HAT_MERGING_OK | HAT_LOADCACHING_OK)) {
PTE_SET(pte, PT_NOCACHE);
if (x86_feature & X86_PAT)
PTE_SET(pte, (level == 0) ? PT_PAT_4K : PT_PAT_LARGE);
else
PTE_SET(pte, PT_WRITETHRU);
} else {
panic("hati_mkpte(): bad caching attributes: %x\n", cache_attr);
}
return (pte);
}
/*
* Duplicate address translations of the parent to the child.
* This function really isn't used anymore.
*/
/*ARGSUSED*/
int
hat_dup(hat_t *old, hat_t *new, caddr_t addr, size_t len, uint_t flag)
{
ASSERT((uintptr_t)addr < kernelbase);
ASSERT(new != kas.a_hat);
ASSERT(old != kas.a_hat);
return (0);
}
/*
* Allocate any hat resources required for a process being swapped in.
*/
/*ARGSUSED*/
void
hat_swapin(hat_t *hat)
{
/* do nothing - we let everything fault back in */
}
/*
* Unload all translations associated with an address space of a process
* that is being swapped out.
*/
void
hat_swapout(hat_t *hat)
{
uintptr_t vaddr = (uintptr_t)0;
uintptr_t eaddr = _userlimit;
htable_t *ht = NULL;
level_t l;
/*
* We can't just call hat_unload(hat, 0, _userlimit...) here, because
* seg_spt and shared pagetables can't be swapped out.
* Take a look at segspt_shmswapout() - it's a big no-op.
*
* Instead we'll walk through all the address space and unload
* any mappings which we are sure are not shared, not locked.
*/
ASSERT(IS_PAGEALIGNED(vaddr));
ASSERT(IS_PAGEALIGNED(eaddr));
ASSERT(AS_LOCK_HELD(hat->hat_as, &hat->hat_as->a_lock));
if ((uintptr_t)hat->hat_as->a_userlimit < eaddr)
eaddr = (uintptr_t)hat->hat_as->a_userlimit;
while (vaddr < eaddr) {
(void) htable_walk(hat, &ht, &vaddr, eaddr);
if (ht == NULL)
break;
ASSERT(!IN_VA_HOLE(vaddr));
/*
* If the page table is shared skip its entire range.
* This code knows that only level 0 page tables are shared
*/
l = ht->ht_level;
if (ht->ht_flags & HTABLE_SHARED_PFN) {
ASSERT(l == 0);
vaddr = ht->ht_vaddr + LEVEL_SIZE(1);
htable_release(ht);
ht = NULL;
continue;
}
/*
* If the page table has no locked entries, unload this one.
*/
if (ht->ht_lock_cnt == 0)
hat_unload(hat, (caddr_t)vaddr, LEVEL_SIZE(l),
HAT_UNLOAD_UNMAP);
/*
* If we have a level 0 page table with locked entries,
* skip the entire page table, otherwise skip just one entry.
*/
if (ht->ht_lock_cnt > 0 && l == 0)
vaddr = ht->ht_vaddr + LEVEL_SIZE(1);
else
vaddr += LEVEL_SIZE(l);
}
if (ht)
htable_release(ht);
/*
* We're in swapout because the system is low on memory, so
* go back and flush all the htables off the cached list.
*/
htable_purge_hat(hat);
}
/*
* returns number of bytes that have valid mappings in hat.
*/
size_t
hat_get_mapped_size(hat_t *hat)
{
size_t total = 0;
int l;
for (l = 0; l <= mmu.max_page_level; l++)
total += (hat->hat_pages_mapped[l] << LEVEL_SHIFT(l));
return (total);
}
/*
* enable/disable collection of stats for hat.
*/
int
hat_stats_enable(hat_t *hat)
{
atomic_add_32(&hat->hat_stats, 1);
return (1);
}
void
hat_stats_disable(hat_t *hat)
{
atomic_add_32(&hat->hat_stats, -1);
}
/*
* Utility to sync the ref/mod bits from a page table entry to the page_t
* We must be holding the mapping list lock when this is called.
*/
static void
hati_sync_pte_to_page(page_t *pp, x86pte_t pte, level_t level)
{
uint_t rm = 0;
pgcnt_t pgcnt;
if (PTE_GET(pte, PT_NOSYNC))
return;
if (PTE_GET(pte, PT_REF))
rm |= P_REF;
if (PTE_GET(pte, PT_MOD))
rm |= P_MOD;
if (rm == 0)
return;
/*
* sync to all constituent pages of a large page
*/
ASSERT(x86_hm_held(pp));
pgcnt = page_get_pagecnt(level);
ASSERT(IS_P2ALIGNED(pp->p_pagenum, pgcnt));
for (; pgcnt > 0; --pgcnt) {
/*
* hat_page_demote() can't decrease
* pszc below this mapping size
* since this large mapping existed after we
* took mlist lock.
*/
ASSERT(pp->p_szc >= level);
hat_page_setattr(pp, rm);
++pp;
}
}
/*
* This the set of PTE bits for PFN, permissions and caching
* that require a TLB flush (hat_demap) if changed on a HAT_LOAD_REMAP
*/
#define PT_REMAP_BITS \
(PT_PADDR | PT_NX | PT_WRITABLE | PT_WRITETHRU | \
PT_NOCACHE | PT_PAT_4K | PT_PAT_LARGE)
#define REMAPASSERT(EX) if (!(EX)) panic("hati_pte_map: " #EX)
/*
* Do the low-level work to get a mapping entered into a HAT's pagetables
* and in the mapping list of the associated page_t.
*/
static void
hati_pte_map(
htable_t *ht,
uint_t entry,
page_t *pp,
x86pte_t pte,
int flags,
void *pte_ptr)
{
hat_t *hat = ht->ht_hat;
x86pte_t old_pte;
level_t l = ht->ht_level;
hment_t *hm;
uint_t is_consist;
/*
* Is this a consistant (ie. need mapping list lock) mapping?
*/
is_consist = (pp != NULL && (flags & HAT_LOAD_NOCONSIST) == 0);
/*
* Track locked mapping count in the htable. Do this first,
* as we track locking even if there already is a mapping present.
*/
if ((flags & HAT_LOAD_LOCK) != 0 && hat != kas.a_hat)
HTABLE_LOCK_INC(ht);
/*
* Acquire the page's mapping list lock and get an hment to use.
* Note that hment_prepare() might return NULL.
*/
if (is_consist) {
x86_hm_enter(pp);
hm = hment_prepare(ht, entry, pp);
}
/*
* Set the new pte, retrieving the old one at the same time.
*/
old_pte = x86pte_set(ht, entry, pte, pte_ptr);
/*
* If the mapping didn't change there is nothing more to do.
*/
if (PTE_EQUIV(pte, old_pte)) {
if (is_consist) {
x86_hm_exit(pp);
if (hm != NULL)
hment_free(hm);
}
return;
}
/*
* Install a new mapping in the page's mapping list
*/
if (!PTE_ISVALID(old_pte)) {
if (is_consist) {
hment_assign(ht, entry, pp, hm);
x86_hm_exit(pp);
} else {
ASSERT(flags & HAT_LOAD_NOCONSIST);
}
HTABLE_INC(ht->ht_valid_cnt);
PGCNT_INC(hat, l);
return;
}
/*
* Remap's are more complicated:
* - HAT_LOAD_REMAP must be specified if changing the pfn.
* We also require that NOCONSIST be specified.
* - Otherwise only permission or caching bits may change.
*/
if (!PTE_ISPAGE(old_pte, l))
panic("non-null/page mapping pte=" FMT_PTE, old_pte);
if (PTE2PFN(old_pte, l) != PTE2PFN(pte, l)) {
REMAPASSERT(flags & HAT_LOAD_REMAP);
REMAPASSERT(flags & HAT_LOAD_NOCONSIST);
REMAPASSERT(PTE_GET(old_pte, PT_NOCONSIST));
REMAPASSERT(pf_is_memory(PTE2PFN(old_pte, l)) ==
pf_is_memory(PTE2PFN(pte, l)));
REMAPASSERT(!is_consist);
}
/*
* We only let remaps change the bits for PFNs, permissions
* or caching type.
*/
ASSERT(PTE_GET(old_pte, ~(PT_REMAP_BITS | PT_REF | PT_MOD)) ==
PTE_GET(pte, ~PT_REMAP_BITS));
/*
* A remap requires invalidating the TLBs, since remapping the
* same PFN requires NOCONSIST, we don't have to sync R/M bits.
*/
hat_demap(hat, htable_e2va(ht, entry));
/*
* We don't create any mapping list entries on a remap, so release
* any allocated hment after we drop the mapping list lock.
*/
if (is_consist) {
x86_hm_exit(pp);
if (hm != NULL)
hment_free(hm);
}
}
/*
* The t_hatdepth field is an 8-bit counter. We use the lower seven bits
* to track exactly how deep we are in the memload->kmem_alloc recursion.
* If the depth is greater than 1, that indicates that we are performing a
* hat operation to satisfy another hat operation. To prevent infinite
* recursion, we switch over to using pre-allocated "reserves" of htables
* and hments.
*
* The uppermost bit is used to indicate that we are transitioning away
* from being the reserves thread. See hati_reserves_exit() for the
* details.
*/
#define EXITING_FLAG (1 << 7)
#define DEPTH_MASK (~EXITING_FLAG)
#define HAT_DEPTH(t) ((t)->t_hatdepth & DEPTH_MASK)
#define EXITING_RESERVES(t) ((t)->t_hatdepth & EXITING_FLAG)
/*
* Access to reserves for HAT_NO_KALLOC is single threaded.
* If someone else is in the reserves, we'll politely wait for them
* to finish. This keeps normal hat_memload()s from eating up
* the mappings needed to replenish the reserve.
*/
static void
hati_reserves_enter(uint_t kmem_for_hat)
{
/*
* 64 is an arbitrary number to catch serious problems. I'm not
* sure what the absolute maximum depth is, but it should be
* substantially less than this.
*/
ASSERT(HAT_DEPTH(curthread) < 64);
/*
* If we are doing a memload to satisfy a kmem operation, we enter
* the reserves immediately; we don't wait to recurse to a second
* level of memload.
*/
ASSERT(kmem_for_hat < 2);
curthread->t_hatdepth += (1 + kmem_for_hat);
if (hat_reserves_thread == curthread || use_boot_reserve)
return;
if (HAT_DEPTH(curthread) > 1 || hat_reserves_thread != NULL) {
mutex_enter(&hat_reserves_lock);
while (hat_reserves_thread != NULL)
cv_wait(&hat_reserves_cv, &hat_reserves_lock);
if (HAT_DEPTH(curthread) > 1)
hat_reserves_thread = curthread;
mutex_exit(&hat_reserves_lock);
}
}
/*
* If we are the reserves_thread and we've finally finished with all our
* memloads (ie. no longer doing hat slabs), we can release our use of the
* reserve.
*/
static void
hati_reserves_exit(uint_t kmem_for_hat)
{
ASSERT(kmem_for_hat < 2);
curthread->t_hatdepth -= (1 + kmem_for_hat);
/*
* Simple case: either we are not the reserves thread, or we are
* the reserves thread and we are nested deeply enough that we
* should still be the reserves thread.
*
* Note: we may not become the reserves thread after we recursively
* enter our second HAT routine, but we don't stop being the
* reserves thread until we exit the toplevel HAT routine. This is
* to work around vmem's inability to determine when an allocation
* should be satisfied from the hat_memload arena, which can lead
* to an infinite loop of memload->vmem_populate->memload->.
*/
if (curthread != hat_reserves_thread || HAT_DEPTH(curthread) > 0 ||
use_boot_reserve)
return;
mutex_enter(&hat_reserves_lock);
ASSERT(hat_reserves_thread == curthread);
hat_reserves_thread = NULL;
cv_broadcast(&hat_reserves_cv);
mutex_exit(&hat_reserves_lock);
/*
* As we leave the reserves, we want to be sure the reserve lists
* aren't overstocked. Freeing excess reserves requires that we
* call kmem_free(), which may require additional allocations,
* causing us to re-enter the reserves. To avoid infinite
* recursion, we only try to adjust reserves at the very top level.
*/
if (!kmem_for_hat && !EXITING_RESERVES(curthread)) {
curthread->t_hatdepth |= EXITING_FLAG;
htable_adjust_reserve();
hment_adjust_reserve();
curthread->t_hatdepth &= (~EXITING_FLAG);
}
/*
* just in case something went wrong in doing adjust reserves
*/
ASSERT(hat_reserves_thread != curthread);
}
/*
* Internal routine to load a single page table entry.
*/
static void
hati_load_common(
hat_t *hat,
uintptr_t va,
page_t *pp,
uint_t attr,
uint_t flags,
level_t level,
pfn_t pfn)
{
htable_t *ht;
uint_t entry;
x86pte_t pte;
uint_t kmem_for_hat = (flags & HAT_NO_KALLOC) ? 1 : 0;
ASSERT(hat == kas.a_hat ||
AS_LOCK_HELD(hat->hat_as, &hat->hat_as->a_lock));
if (flags & HAT_LOAD_SHARE)
hat->hat_flags |= HAT_SHARED;
/*
* Find the page table that maps this page if it already exists.
*/
ht = htable_lookup(hat, va, level);
/*
* All threads go through hati_reserves_enter() to at least wait
* for any existing reserves user to finish. This helps reduce
* pressure on the reserves. In addition, if this thread needs
* to become the new reserve user it will.
*/
hati_reserves_enter(kmem_for_hat);
ASSERT(HAT_DEPTH(curthread) == 1 || va >= kernelbase);
/*
* Kernel memloads for HAT data should never use hments!
* If it did that would seriously complicate the reserves system, since
* hment_alloc() would need to know about HAT_NO_KALLOC.
*
* We also must have HAT_LOAD_NOCONSIST if page_t is NULL.
*/
if (HAT_DEPTH(curthread) > 1 || pp == NULL)
flags |= HAT_LOAD_NOCONSIST;
if (ht == NULL) {
ht = htable_create(hat, va, level, NULL);
ASSERT(ht != NULL);
}
entry = htable_va2entry(va, ht);
/*
* a bunch of paranoid error checking
*/
ASSERT(ht->ht_busy > 0);
if (ht->ht_vaddr > va || va > HTABLE_LAST_PAGE(ht))
panic("hati_load_common: bad htable %p, va %p", ht, (void *)va);
ASSERT(ht->ht_level == level);
/*
* construct the new PTE
*/
if (hat == kas.a_hat)
attr &= ~PROT_USER;
pte = hati_mkpte(pfn, attr, level, flags);
if (hat == kas.a_hat && va >= kernelbase)
PTE_SET(pte, mmu.pt_global);
/*
* establish the mapping
*/
hati_pte_map(ht, entry, pp, pte, flags, NULL);
/*
* release the htable and any reserves
*/
htable_release(ht);
hati_reserves_exit(kmem_for_hat);
}
/*
* special case of hat_memload to deal with some kernel addrs for performance
*/
static void
hat_kmap_load(
caddr_t addr,
page_t *pp,
uint_t attr,
uint_t flags)
{
uintptr_t va = (uintptr_t)addr;
x86pte_t pte;
pfn_t pfn = page_pptonum(pp);
pgcnt_t pg_off = mmu_btop(va - mmu.kmap_addr);
htable_t *ht;
uint_t entry;
void *pte_ptr;
/*
* construct the requested PTE
*/
attr &= ~PROT_USER;
attr |= HAT_STORECACHING_OK;
pte = hati_mkpte(pfn, attr, 0, flags);
PTE_SET(pte, mmu.pt_global);
/*
* Figure out the pte_ptr and htable and use common code to finish up
*/
if (mmu.pae_hat)
pte_ptr = mmu.kmap_ptes + pg_off;
else
pte_ptr = (x86pte32_t *)mmu.kmap_ptes + pg_off;
ht = mmu.kmap_htables[(va - mmu.kmap_htables[0]->ht_vaddr) >>
LEVEL_SHIFT(1)];
entry = htable_va2entry(va, ht);
hati_pte_map(ht, entry, pp, pte, flags, pte_ptr);
}
/*
* hat_memload() - load a translation to the given page struct
*
* Flags for hat_memload/hat_devload/hat_*attr.
*
* HAT_LOAD Default flags to load a translation to the page.
*
* HAT_LOAD_LOCK Lock down mapping resources; hat_map(), hat_memload(),
* and hat_devload().
*
* HAT_LOAD_NOCONSIST Do not add mapping to page_t mapping list.
* sets PT_NOCONSIST (soft bit)
*
* HAT_LOAD_SHARE A flag to hat_memload() to indicate h/w page tables
* that map some user pages (not kas) is shared by more
* than one process (eg. ISM).
*
* HAT_LOAD_REMAP Reload a valid pte with a different page frame.
*
* HAT_NO_KALLOC Do not kmem_alloc while creating the mapping; at this
* point, it's setting up mapping to allocate internal
* hat layer data structures. This flag forces hat layer
* to tap its reserves in order to prevent infinite
* recursion.
*
* The following is a protection attribute (like PROT_READ, etc.)
*
* HAT_NOSYNC set PT_NOSYNC (soft bit) - this mapping's ref/mod bits
* are never cleared.
*
* Installing new valid PTE's and creation of the mapping list
* entry are controlled under the same lock. It's derived from the
* page_t being mapped.
*/
static uint_t supported_memload_flags =
HAT_LOAD | HAT_LOAD_LOCK | HAT_LOAD_ADV | HAT_LOAD_NOCONSIST |
HAT_LOAD_SHARE | HAT_NO_KALLOC | HAT_LOAD_REMAP | HAT_LOAD_TEXT;
void
hat_memload(
hat_t *hat,
caddr_t addr,
page_t *pp,
uint_t attr,
uint_t flags)
{
uintptr_t va = (uintptr_t)addr;
level_t level = 0;
pfn_t pfn = page_pptonum(pp);
HATIN(hat_memload, hat, addr, (size_t)MMU_PAGESIZE);
ASSERT(IS_PAGEALIGNED(va));
ASSERT(hat == kas.a_hat || va <= kernelbase);
ASSERT(hat == kas.a_hat ||
AS_LOCK_HELD(hat->hat_as, &hat->hat_as->a_lock));
ASSERT((flags & supported_memload_flags) == flags);
ASSERT(!IN_VA_HOLE(va));
ASSERT(!PP_ISFREE(pp));
/*
* kernel address special case for performance.
*/
if (mmu.kmap_addr <= va && va < mmu.kmap_eaddr) {
ASSERT(hat == kas.a_hat);
hat_kmap_load(addr, pp, attr, flags);
return;
}
/*
* This is used for memory with normal caching enabled, so
* always set HAT_STORECACHING_OK.
*/
attr |= HAT_STORECACHING_OK;
hati_load_common(hat, va, pp, attr, flags, level, pfn);
HATOUT(hat_memload, hat, addr);
}
/*
* Load the given array of page structs using large pages when possible
*/
void
hat_memload_array(
hat_t *hat,
caddr_t addr,
size_t len,
page_t **pages,
uint_t attr,
uint_t flags)
{
uintptr_t va = (uintptr_t)addr;
uintptr_t eaddr = va + len;
level_t level;
size_t pgsize;
pgcnt_t pgindx = 0;
pfn_t pfn;
pgcnt_t i;
HATIN(hat_memload_array, hat, addr, len);
ASSERT(IS_PAGEALIGNED(va));
ASSERT(hat == kas.a_hat || va + len <= kernelbase);
ASSERT(hat == kas.a_hat ||
AS_LOCK_HELD(hat->hat_as, &hat->hat_as->a_lock));
ASSERT((flags & supported_memload_flags) == flags);
/*
* memload is used for memory with full caching enabled, so
* set HAT_STORECACHING_OK.
*/
attr |= HAT_STORECACHING_OK;
/*
* handle all pages using largest possible pagesize
*/
while (va < eaddr) {
/*
* decide what level mapping to use (ie. pagesize)
*/
pfn = page_pptonum(pages[pgindx]);
for (level = mmu.max_page_level; ; --level) {
pgsize = LEVEL_SIZE(level);
if (level == 0)
break;
if (!IS_P2ALIGNED(va, pgsize) ||
(eaddr - va) < pgsize ||
!IS_P2ALIGNED(pfn << MMU_PAGESHIFT, pgsize))
continue;
/*
* To use a large mapping of this size, all the
* pages we are passed must be sequential subpages
* of the large page.
* hat_page_demote() can't change p_szc because
* all pages are locked.
*/
if (pages[pgindx]->p_szc >= level) {
for (i = 0; i < mmu_btop(pgsize); ++i) {
if (pfn + i !=
page_pptonum(pages[pgindx + i]))
break;
ASSERT(pages[pgindx + i]->p_szc >=
level);
ASSERT(pages[pgindx] + i ==
pages[pgindx + i]);
}
if (i == mmu_btop(pgsize))
break;
}
}
/*
* Shared page tables for DISM might have a pre-existing
* level 0 page table that wasn't unlinked from all the
* sharing hats. If we hit this for a large page, back off
* to using level 0 pages.
*
* This can't be made better (ie. use large pages) until we
* track all the htable's sharing and rewrite hat_pageunload().
* Note that would cost a pointer in htable_t for a rare case.
*
* Since the 32 bit kernel caches empty page tables, check
* the kernel too.
*/
if ((hat == kas.a_hat || (hat->hat_flags & HAT_SHARED)) &&
level > 0) {
htable_t *lower;
lower = htable_getpte(hat, va, NULL, NULL, level - 1);
if (lower != NULL) {
level = 0;
pgsize = LEVEL_SIZE(0);
htable_release(lower);
}
}
/*
* load this page mapping
*/
ASSERT(!IN_VA_HOLE(va));
hati_load_common(hat, va, pages[pgindx], attr, flags,
level, pfn);
/*
* move to next page
*/
va += pgsize;
pgindx += mmu_btop(pgsize);
}
HATOUT(hat_memload_array, hat, addr);
}
/*
* void hat_devload(hat, addr, len, pf, attr, flags)
* load/lock the given page frame number
*
* Advisory ordering attributes. Apply only to device mappings.
*
* HAT_STRICTORDER: the CPU must issue the references in order, as the
* programmer specified. This is the default.
* HAT_UNORDERED_OK: the CPU may reorder the references (this is all kinds
* of reordering; store or load with store or load).
* HAT_MERGING_OK: merging and batching: the CPU may merge individual stores
* to consecutive locations (for example, turn two consecutive byte
* stores into one halfword store), and it may batch individual loads
* (for example, turn two consecutive byte loads into one halfword load).
* This also implies re-ordering.
* HAT_LOADCACHING_OK: the CPU may cache the data it fetches and reuse it
* until another store occurs. The default is to fetch new data
* on every load. This also implies merging.
* HAT_STORECACHING_OK: the CPU may keep the data in the cache and push it to
* the device (perhaps with other data) at a later time. The default is
* to push the data right away. This also implies load caching.
*
* Equivalent of hat_memload(), but can be used for device memory where
* there are no page_t's and we support additional flags (write merging, etc).
* Note that we can have large page mappings with this interface.
*/
int supported_devload_flags = HAT_LOAD | HAT_LOAD_LOCK |
HAT_LOAD_NOCONSIST | HAT_STRICTORDER | HAT_UNORDERED_OK |
HAT_MERGING_OK | HAT_LOADCACHING_OK | HAT_STORECACHING_OK;
void
hat_devload(
hat_t *hat,
caddr_t addr,
size_t len,
pfn_t pfn,
uint_t attr,
int flags)
{
uintptr_t va = ALIGN2PAGE(addr);
uintptr_t eva = va + len;
level_t level;
size_t pgsize;
page_t *pp;
int f; /* per PTE copy of flags - maybe modified */
uint_t a; /* per PTE copy of attr */
HATIN(hat_devload, hat, addr, len);
ASSERT(IS_PAGEALIGNED(va));
ASSERT(hat == kas.a_hat || eva <= kernelbase);
ASSERT(hat == kas.a_hat ||
AS_LOCK_HELD(hat->hat_as, &hat->hat_as->a_lock));
ASSERT((flags & supported_devload_flags) == flags);
/*
* handle all pages
*/
while (va < eva) {
/*
* decide what level mapping to use (ie. pagesize)
*/
for (level = mmu.max_page_level; ; --level) {
pgsize = LEVEL_SIZE(level);
if (level == 0)
break;
if (IS_P2ALIGNED(va, pgsize) &&
(eva - va) >= pgsize &&
IS_P2ALIGNED(pfn, mmu_btop(pgsize)))
break;
}
/*
* Some kernel addresses have permanently existing page tables,
* so be sure to use a compatible pagesize.
*/
if (hat == kas.a_hat && level > 0) {
htable_t *lower;
lower = htable_getpte(hat, va, NULL, NULL, level - 1);
if (lower != NULL) {
level = 0;
pgsize = LEVEL_SIZE(0);
htable_release(lower);
}
}
/*
* If it is memory get page_t and allow caching (this happens
* for the nucleus pages) - though HAT_PLAT_NOCACHE can be used
* to override that. If we don't have a page_t, make sure
* NOCONSIST is set.
*/
a = attr;
f = flags;
if (pf_is_memory(pfn)) {
if (!(a & HAT_PLAT_NOCACHE))
a |= HAT_STORECACHING_OK;
if (f & HAT_LOAD_NOCONSIST)
pp = NULL;
else
pp = page_numtopp_nolock(pfn);
} else {
pp = NULL;
f |= HAT_LOAD_NOCONSIST;
}
/*
* load this page mapping
*/
ASSERT(!IN_VA_HOLE(va));
hati_load_common(hat, va, pp, a, f, level, pfn);
/*
* move to next page
*/
va += pgsize;
pfn += mmu_btop(pgsize);
}
HATOUT(hat_devload, hat, addr);
}
/*
* void hat_unlock(hat, addr, len)
* unlock the mappings to a given range of addresses
*
* Locks are tracked by ht_lock_cnt in the htable.
*/
void
hat_unlock(hat_t *hat, caddr_t addr, size_t len)
{
uintptr_t vaddr = (uintptr_t)addr;
uintptr_t eaddr = vaddr + len;
htable_t *ht = NULL;
/*
* kernel entries are always locked, we don't track lock counts
*/
ASSERT(hat == kas.a_hat || eaddr <= kernelbase);
ASSERT(IS_PAGEALIGNED(vaddr));
ASSERT(IS_PAGEALIGNED(eaddr));
if (hat == kas.a_hat)
return;
if (eaddr > _userlimit)
panic("hat_unlock() address out of range - above _userlimit");
ASSERT(AS_LOCK_HELD(hat->hat_as, &hat->hat_as->a_lock));
while (vaddr < eaddr) {
(void) htable_walk(hat, &ht, &vaddr, eaddr);
if (ht == NULL)
break;
ASSERT(!IN_VA_HOLE(vaddr));
if (ht->ht_lock_cnt < 1)
panic("hat_unlock(): lock_cnt < 1, "
"htable=%p, vaddr=%p\n", ht, (caddr_t)vaddr);
HTABLE_LOCK_DEC(ht);
vaddr += LEVEL_SIZE(ht->ht_level);
}
if (ht)
htable_release(ht);
}
/*
* Cross call service routine to demap a virtual page on
* the current CPU or flush all mappings in TLB.
*/
/*ARGSUSED*/
static int
hati_demap_func(xc_arg_t a1, xc_arg_t a2, xc_arg_t a3)
{
hat_t *hat = (hat_t *)a1;
caddr_t addr = (caddr_t)a2;
/*
* If the target hat isn't the kernel and this CPU isn't operating
* in the target hat, we can ignore the cross call.
*/
if (hat != kas.a_hat && hat != CPU->cpu_current_hat)
return (0);
/*
* For a normal address, we just flush one page mapping
*/
if ((uintptr_t)addr != DEMAP_ALL_ADDR) {
mmu_tlbflush_entry((caddr_t)addr);
return (0);
}
/*
* Otherwise we reload cr3 to effect a complete TLB flush.
*
* A reload of cr3 on a VLP process also means we must also recopy in
* the pte values from the struct hat
*/
if (hat->hat_flags & HAT_VLP) {
#if defined(__amd64)
x86pte_t *vlpptep = CPU->cpu_hat_info->hci_vlp_l2ptes;
VLP_COPY(hat->hat_vlp_ptes, vlpptep);
#elif defined(__i386)
reload_pae32(hat, CPU);
#endif
}
reload_cr3();
return (0);
}
/*
* Internal routine to do cross calls to invalidate a range of pages on
* all CPUs using a given hat.
*/
void
hat_demap(hat_t *hat, uintptr_t va)
{
extern int flushes_require_xcalls; /* from mp_startup.c */
cpuset_t justme;
/*
* If the hat is being destroyed, there are no more users, so
* demap need not do anything.
*/
if (hat->hat_flags & HAT_FREEING)
return;
/*
* If demapping from a shared pagetable, we best demap the
* entire set of user TLBs, since we don't know what addresses
* these were shared at.
*/
if (hat->hat_flags & HAT_SHARED) {
hat = kas.a_hat;
va = DEMAP_ALL_ADDR;
}
/*
* if not running with multiple CPUs, don't use cross calls
*/
if (panicstr || !flushes_require_xcalls) {
(void) hati_demap_func((xc_arg_t)hat, (xc_arg_t)va, NULL);
return;
}
/*
* All CPUs must see kernel hat changes.
*/
if (hat == kas.a_hat) {
kpreempt_disable();
xc_call((xc_arg_t)hat, (xc_arg_t)va, NULL,
X_CALL_HIPRI, khat_cpuset, hati_demap_func);
kpreempt_enable();
return;
}
/*
* Otherwise we notify CPUs currently running in this HAT
*/
hat_enter(hat);
kpreempt_disable();
CPUSET_ONLY(justme, CPU->cpu_id);
if (CPUSET_ISEQUAL(hat->hat_cpus, justme))
(void) hati_demap_func((xc_arg_t)hat, (xc_arg_t)va, NULL);
else
xc_call((xc_arg_t)hat, (xc_arg_t)va, NULL,
X_CALL_HIPRI, hat->hat_cpus, hati_demap_func);
kpreempt_enable();
hat_exit(hat);
}
/*
* Interior routine for HAT_UNLOADs from hat_unload_callback(),
* hat_kmap_unload() OR from hat_steal() code. This routine doesn't
* handle releasing of the htables.
*/
void
hat_pte_unmap(
htable_t *ht,
uint_t entry,
uint_t flags,
x86pte_t old_pte,
void *pte_ptr)
{
hat_t *hat = ht->ht_hat;
hment_t *hm = NULL;
page_t *pp = NULL;
level_t l = ht->ht_level;
pfn_t pfn;
/*
* We always track the locking counts, even if nothing is unmapped
*/
if ((flags & HAT_UNLOAD_UNLOCK) != 0 && hat != kas.a_hat) {
ASSERT(ht->ht_lock_cnt > 0);
HTABLE_LOCK_DEC(ht);
}
/*
* Figure out which page's mapping list lock to acquire using the PFN
* passed in "old" PTE. We then attempt to invalidate the PTE.
* If another thread, probably a hat_pageunload, has asynchronously
* unmapped/remapped this address we'll loop here.
*/
ASSERT(ht->ht_busy > 0);
while (PTE_ISVALID(old_pte)) {
pfn = PTE2PFN(old_pte, l);
if (PTE_GET(old_pte, PT_NOCONSIST)) {
pp = NULL;
} else {
pp = page_numtopp_nolock(pfn);
if (pp == NULL) {
panic("no page_t, not NOCONSIST: old_pte="
FMT_PTE " ht=%lx entry=0x%x pte_ptr=%lx",
old_pte, (uintptr_t)ht, entry,
(uintptr_t)pte_ptr);
}
x86_hm_enter(pp);
}
/*
* If freeing the address space, check that the PTE
* hasn't changed, as the mappings are no longer in use by
* any thread, invalidation is unnecessary.
* If not freeing, do a full invalidate.
*/
if (hat->hat_flags & HAT_FREEING)
old_pte = x86pte_get(ht, entry);
else
old_pte =
x86pte_invalidate_pfn(ht, entry, pfn, pte_ptr);
/*
* If the page hadn't changed we've unmapped it and can proceed
*/
if (PTE_ISVALID(old_pte) && PTE2PFN(old_pte, l) == pfn)
break;
/*
* Otherwise, we'll have to retry with the current old_pte.
* Drop the hment lock, since the pfn may have changed.
*/
if (pp != NULL) {
x86_hm_exit(pp);
pp = NULL;
} else {
ASSERT(PTE_GET(old_pte, PT_NOCONSIST));
}
}
/*
* If the old mapping wasn't valid, there's nothing more to do
*/
if (!PTE_ISVALID(old_pte)) {
if (pp != NULL)
x86_hm_exit(pp);
return;
}
/*
* Take care of syncing any MOD/REF bits and removing the hment.
*/
if (pp != NULL) {
if (!(flags & HAT_UNLOAD_NOSYNC))
hati_sync_pte_to_page(pp, old_pte, l);
hm = hment_remove(pp, ht, entry);
x86_hm_exit(pp);
if (hm != NULL)
hment_free(hm);
}
/*
* Handle book keeping in the htable and hat
*/
ASSERT(ht->ht_valid_cnt > 0);
HTABLE_DEC(ht->ht_valid_cnt);
PGCNT_DEC(hat, l);
}
/*
* very cheap unload implementation to special case some kernel addresses
*/
static void
hat_kmap_unload(caddr_t addr, size_t len, uint_t flags)
{
uintptr_t va = (uintptr_t)addr;
uintptr_t eva = va + len;
pgcnt_t pg_off;
htable_t *ht;
uint_t entry;
void *pte_ptr;
x86pte_t old_pte;
for (; va < eva; va += MMU_PAGESIZE) {
/*
* Get the PTE
*/
pg_off = mmu_btop(va - mmu.kmap_addr);
if (mmu.pae_hat) {
pte_ptr = mmu.kmap_ptes + pg_off;
ATOMIC_LOAD64((x86pte_t *)pte_ptr, old_pte);
} else {
pte_ptr = (x86pte32_t *)mmu.kmap_ptes + pg_off;
old_pte = *(x86pte32_t *)pte_ptr;
}
/*
* get the htable / entry
*/
ht = mmu.kmap_htables[(va - mmu.kmap_htables[0]->ht_vaddr)
>> LEVEL_SHIFT(1)];
entry = htable_va2entry(va, ht);
/*
* use mostly common code to unmap it.
*/
hat_pte_unmap(ht, entry, flags, old_pte, pte_ptr);
}
}
/*
* unload a range of virtual address space (no callback)
*/
void
hat_unload(hat_t *hat, caddr_t addr, size_t len, uint_t flags)
{
uintptr_t va = (uintptr_t)addr;
ASSERT(hat == kas.a_hat || va + len <= kernelbase);
/*
* special case for performance.
*/
if (mmu.kmap_addr <= va && va < mmu.kmap_eaddr) {
ASSERT(hat == kas.a_hat);
hat_kmap_unload(addr, len, flags);
return;
}
hat_unload_callback(hat, addr, len, flags, NULL);
}
/*
* Do the callbacks for ranges being unloaded.
*/
typedef struct range_info {
uintptr_t rng_va;
ulong_t rng_cnt;
level_t rng_level;
} range_info_t;
static void
handle_ranges(hat_callback_t *cb, uint_t cnt, range_info_t *range)
{
/*
* do callbacks to upper level VM system
*/
while (cb != NULL && cnt > 0) {
--cnt;
cb->hcb_start_addr = (caddr_t)range[cnt].rng_va;
cb->hcb_end_addr = cb->hcb_start_addr;
cb->hcb_end_addr +=
range[cnt].rng_cnt << LEVEL_SIZE(range[cnt].rng_level);
cb->hcb_function(cb);
}
}
/*
* Unload a given range of addresses (has optional callback)
*
* Flags:
* define HAT_UNLOAD 0x00
* define HAT_UNLOAD_NOSYNC 0x02
* define HAT_UNLOAD_UNLOCK 0x04
* define HAT_UNLOAD_OTHER 0x08 - not used
* define HAT_UNLOAD_UNMAP 0x10 - same as HAT_UNLOAD
*/
#define MAX_UNLOAD_CNT (8)
void
hat_unload_callback(
hat_t *hat,
caddr_t addr,
size_t len,
uint_t flags,
hat_callback_t *cb)
{
uintptr_t vaddr = (uintptr_t)addr;
uintptr_t eaddr = vaddr + len;
htable_t *ht = NULL;
uint_t entry;
uintptr_t contig_va = (uintptr_t)-1L;
range_info_t r[MAX_UNLOAD_CNT];
uint_t r_cnt = 0;
x86pte_t old_pte;
HATIN(hat_unload_callback, hat, addr, len);
ASSERT(hat == kas.a_hat || eaddr <= kernelbase);
ASSERT(IS_PAGEALIGNED(vaddr));
ASSERT(IS_PAGEALIGNED(eaddr));
while (vaddr < eaddr) {
old_pte = htable_walk(hat, &ht, &vaddr, eaddr);
if (ht == NULL)
break;
ASSERT(!IN_VA_HOLE(vaddr));
if (vaddr < (uintptr_t)addr)
panic("hat_unload_callback(): unmap inside large page");
/*
* We'll do the call backs for contiguous ranges
*/
if (vaddr != contig_va ||
(r_cnt > 0 && r[r_cnt - 1].rng_level != ht->ht_level)) {
if (r_cnt == MAX_UNLOAD_CNT) {
handle_ranges(cb, r_cnt, r);
r_cnt = 0;
}
r[r_cnt].rng_va = vaddr;
r[r_cnt].rng_cnt = 0;
r[r_cnt].rng_level = ht->ht_level;
++r_cnt;
}
/*
* Unload one mapping from the page tables.
*/
entry = htable_va2entry(vaddr, ht);
hat_pte_unmap(ht, entry, flags, old_pte, NULL);
ASSERT(ht->ht_level <= mmu.max_page_level);
vaddr += LEVEL_SIZE(ht->ht_level);
contig_va = vaddr;
++r[r_cnt - 1].rng_cnt;
}
if (ht)
htable_release(ht);
/*
* handle last range for callbacks
*/
if (r_cnt > 0)
handle_ranges(cb, r_cnt, r);
HATOUT(hat_unload_callback, hat, addr);
}
/*
* synchronize mapping with software data structures
*
* This interface is currently only used by the working set monitor
* driver.
*/
/*ARGSUSED*/
void
hat_sync(hat_t *hat, caddr_t addr, size_t len, uint_t flags)
{
uintptr_t vaddr = (uintptr_t)addr;
uintptr_t eaddr = vaddr + len;
htable_t *ht = NULL;
uint_t entry;
x86pte_t pte;
x86pte_t save_pte;
x86pte_t new;
page_t *pp;
ASSERT(!IN_VA_HOLE(vaddr));
ASSERT(IS_PAGEALIGNED(vaddr));
ASSERT(IS_PAGEALIGNED(eaddr));
ASSERT(hat == kas.a_hat || eaddr <= kernelbase);
for (; vaddr < eaddr; vaddr += LEVEL_SIZE(ht->ht_level)) {
try_again:
pte = htable_walk(hat, &ht, &vaddr, eaddr);
if (ht == NULL)
break;
entry = htable_va2entry(vaddr, ht);
if (PTE_GET(pte, PT_NOSYNC) ||
PTE_GET(pte, PT_REF | PT_MOD) == 0)
continue;
/*
* We need to acquire the mapping list lock to protect
* against hat_pageunload(), hat_unload(), etc.
*/
pp = page_numtopp_nolock(PTE2PFN(pte, ht->ht_level));
if (pp == NULL)
break;
x86_hm_enter(pp);
save_pte = pte;
pte = x86pte_get(ht, entry);
if (pte != save_pte) {
x86_hm_exit(pp);
goto try_again;
}
if (PTE_GET(pte, PT_NOSYNC) ||
PTE_GET(pte, PT_REF | PT_MOD) == 0) {
x86_hm_exit(pp);
continue;
}
/*
* Need to clear ref or mod bits. We may compete with
* hardware updating the R/M bits and have to try again.
*/
if (flags == HAT_SYNC_ZERORM) {
new = pte;
PTE_CLR(new, PT_REF | PT_MOD);
pte = hati_update_pte(ht, entry, pte, new);
if (pte != 0) {
x86_hm_exit(pp);
goto try_again;
}
} else {
/*
* sync the PTE to the page_t
*/
hati_sync_pte_to_page(pp, save_pte, ht->ht_level);
}
x86_hm_exit(pp);
}
if (ht)
htable_release(ht);
}
/*
* void hat_map(hat, addr, len, flags)
*/
/*ARGSUSED*/
void
hat_map(hat_t *hat, caddr_t addr, size_t len, uint_t flags)
{
/* does nothing */
}
/*
* uint_t hat_getattr(hat, addr, *attr)
* returns attr for <hat,addr> in *attr. returns 0 if there was a
* mapping and *attr is valid, nonzero if there was no mapping and
* *attr is not valid.
*/
uint_t
hat_getattr(hat_t *hat, caddr_t addr, uint_t *attr)
{
uintptr_t vaddr = ALIGN2PAGE(addr);
htable_t *ht = NULL;
x86pte_t pte;
ASSERT(hat == kas.a_hat || vaddr < kernelbase);
if (IN_VA_HOLE(vaddr))
return ((uint_t)-1);
ht = htable_getpte(hat, vaddr, NULL, &pte, MAX_PAGE_LEVEL);
if (ht == NULL)
return ((uint_t)-1);
if (!PTE_ISVALID(pte) || !PTE_ISPAGE(pte, ht->ht_level)) {
htable_release(ht);
return ((uint_t)-1);
}
*attr = PROT_READ;
if (PTE_GET(pte, PT_WRITABLE))
*attr |= PROT_WRITE;
if (PTE_GET(pte, PT_USER))
*attr |= PROT_USER;
if (!PTE_GET(pte, mmu.pt_nx))
*attr |= PROT_EXEC;
if (PTE_GET(pte, PT_NOSYNC))
*attr |= HAT_NOSYNC;
htable_release(ht);
return (0);
}
/*
* hat_updateattr() applies the given attribute change to an existing mapping
*/
#define HAT_LOAD_ATTR 1
#define HAT_SET_ATTR 2
#define HAT_CLR_ATTR 3
static void
hat_updateattr(hat_t *hat, caddr_t addr, size_t len, uint_t attr, int what)
{
uintptr_t vaddr = (uintptr_t)addr;
uintptr_t eaddr = (uintptr_t)addr + len;
htable_t *ht = NULL;
uint_t entry;
x86pte_t oldpte, newpte;
page_t *pp;
ASSERT(IS_PAGEALIGNED(vaddr));
ASSERT(IS_PAGEALIGNED(eaddr));
ASSERT(hat == kas.a_hat ||
AS_LOCK_HELD(hat->hat_as, &hat->hat_as->a_lock));
for (; vaddr < eaddr; vaddr += LEVEL_SIZE(ht->ht_level)) {
try_again:
oldpte = htable_walk(hat, &ht, &vaddr, eaddr);
if (ht == NULL)
break;
if (PTE_GET(oldpte, PT_NOCONSIST))
continue;
pp = page_numtopp_nolock(PTE2PFN(oldpte, ht->ht_level));
if (pp == NULL)
continue;
x86_hm_enter(pp);
newpte = oldpte;
/*
* We found a page table entry in the desired range,
* figure out the new attributes.
*/
if (what == HAT_SET_ATTR || what == HAT_LOAD_ATTR) {
if ((attr & PROT_WRITE) &&
!PTE_GET(oldpte, PT_WRITABLE))
newpte |= PT_WRITABLE;
if ((attr & HAT_NOSYNC) && !PTE_GET(oldpte, PT_NOSYNC))
newpte |= PT_NOSYNC;
if ((attr & PROT_EXEC) && PTE_GET(oldpte, mmu.pt_nx))
newpte &= ~mmu.pt_nx;
}
if (what == HAT_LOAD_ATTR) {
if (!(attr & PROT_WRITE) &&
PTE_GET(oldpte, PT_WRITABLE))
newpte &= ~PT_WRITABLE;
if (!(attr & HAT_NOSYNC) && PTE_GET(oldpte, PT_NOSYNC))
newpte &= ~PT_NOSYNC;
if (!(attr & PROT_EXEC) && !PTE_GET(oldpte, mmu.pt_nx))
newpte |= mmu.pt_nx;
}
if (what == HAT_CLR_ATTR) {
if ((attr & PROT_WRITE) && PTE_GET(oldpte, PT_WRITABLE))
newpte &= ~PT_WRITABLE;
if ((attr & HAT_NOSYNC) && PTE_GET(oldpte, PT_NOSYNC))
newpte &= ~PT_NOSYNC;
if ((attr & PROT_EXEC) && !PTE_GET(oldpte, mmu.pt_nx))
newpte |= mmu.pt_nx;
}
/*
* what about PROT_READ or others? this code only handles:
* EXEC, WRITE, NOSYNC
*/
/*
* If new PTE really changed, update the table.
*/
if (newpte != oldpte) {
entry = htable_va2entry(vaddr, ht);
oldpte = hati_update_pte(ht, entry, oldpte, newpte);
if (oldpte != 0) {
x86_hm_exit(pp);
goto try_again;
}
}
x86_hm_exit(pp);
}
if (ht)
htable_release(ht);
}
/*
* Various wrappers for hat_updateattr()
*/
void
hat_setattr(hat_t *hat, caddr_t addr, size_t len, uint_t attr)
{
ASSERT(hat == kas.a_hat || (uintptr_t)addr + len <= kernelbase);
hat_updateattr(hat, addr, len, attr, HAT_SET_ATTR);
}
void
hat_clrattr(hat_t *hat, caddr_t addr, size_t len, uint_t attr)
{
ASSERT(hat == kas.a_hat || (uintptr_t)addr + len <= kernelbase);
hat_updateattr(hat, addr, len, attr, HAT_CLR_ATTR);
}
void
hat_chgattr(hat_t *hat, caddr_t addr, size_t len, uint_t attr)
{
ASSERT(hat == kas.a_hat || (uintptr_t)addr + len <= kernelbase);
hat_updateattr(hat, addr, len, attr, HAT_LOAD_ATTR);
}
void
hat_chgprot(hat_t *hat, caddr_t addr, size_t len, uint_t vprot)
{
ASSERT(hat == kas.a_hat || (uintptr_t)addr + len <= kernelbase);
hat_updateattr(hat, addr, len, vprot & HAT_PROT_MASK, HAT_LOAD_ATTR);
}
/*ARGSUSED*/
void
hat_chgattr_pagedir(hat_t *hat, caddr_t addr, size_t len, uint_t attr)
{
panic("hat_chgattr_pgdir() not supported - used by 80387 emulation");
}
/*
* size_t hat_getpagesize(hat, addr)
* returns pagesize in bytes for <hat, addr>. returns -1 of there is
* no mapping. This is an advisory call.
*/
ssize_t
hat_getpagesize(hat_t *hat, caddr_t addr)
{
uintptr_t vaddr = ALIGN2PAGE(addr);
htable_t *ht;
size_t pagesize;
ASSERT(hat == kas.a_hat || vaddr < kernelbase);
if (IN_VA_HOLE(vaddr))
return (-1);
ht = htable_getpage(hat, vaddr, NULL);
if (ht == NULL)
return (-1);
pagesize = LEVEL_SIZE(ht->ht_level);
htable_release(ht);
return (pagesize);
}
/*
* pfn_t hat_getpfnum(hat, addr)
* returns pfn for <hat, addr> or PFN_INVALID if mapping is invalid.
*/
pfn_t
hat_getpfnum(hat_t *hat, caddr_t addr)
{
uintptr_t vaddr = ALIGN2PAGE(addr);
htable_t *ht;
uint_t entry;
pfn_t pfn = PFN_INVALID;
ASSERT(hat == kas.a_hat || vaddr < kernelbase);
if (khat_running == 0)
panic("hat_getpfnum(): called too early\n");
if (IN_VA_HOLE(vaddr))
return (PFN_INVALID);
/*
* A very common use of hat_getpfnum() is from the DDI for kernel pages.
* Use the kmap_ptes (which also covers the 32 bit heap) to speed
* this up.
*/
if (mmu.kmap_addr <= vaddr && vaddr < mmu.kmap_eaddr) {
x86pte_t pte;
pgcnt_t pg_off;
pg_off = mmu_btop(vaddr - mmu.kmap_addr);
if (mmu.pae_hat) {
ATOMIC_LOAD64(mmu.kmap_ptes + pg_off, pte);
} else {
pte = ((x86pte32_t *)mmu.kmap_ptes)[pg_off];
}
if (!PTE_ISVALID(pte))
return (PFN_INVALID);
/*LINTED [use of constant 0 causes a silly lint warning] */
return (PTE2PFN(pte, 0));
}
ht = htable_getpage(hat, vaddr, &entry);
if (ht == NULL)
return (PFN_INVALID);
ASSERT(vaddr >= ht->ht_vaddr);
ASSERT(vaddr <= HTABLE_LAST_PAGE(ht));
pfn = PTE2PFN(x86pte_get(ht, entry), ht->ht_level);
if (ht->ht_level > 0)
pfn += mmu_btop(vaddr & LEVEL_OFFSET(ht->ht_level));
htable_release(ht);
return (pfn);
}
/*
* hat_getkpfnum() is an obsolete DDI routine, and its use is discouraged.
* Use hat_getpfnum(kas.a_hat, ...) instead.
*
* We'd like to return PFN_INVALID if the mappings have underlying page_t's
* but can't right now due to the fact that some software has grown to use
* this interface incorrectly. So for now when the interface is misused,
* return a warning to the user that in the future it won't work in the
* way they're abusing it, and carry on.
*
* Note that hat_getkpfnum() is never supported on amd64.
*/
#if !defined(__amd64)
pfn_t
hat_getkpfnum(caddr_t addr)
{
pfn_t pfn;
int badcaller = 0;
if (khat_running == 0)
panic("hat_getkpfnum(): called too early\n");
if ((uintptr_t)addr < kernelbase)
return (PFN_INVALID);
if (segkpm && IS_KPM_ADDR(addr)) {
badcaller = 1;
pfn = hat_kpm_va2pfn(addr);
} else {
pfn = hat_getpfnum(kas.a_hat, addr);
badcaller = pf_is_memory(pfn);
}
if (badcaller)
hat_getkpfnum_badcall(caller());
return (pfn);
}
#endif /* __amd64 */
/*
* int hat_probe(hat, addr)
* return 0 if no valid mapping is present. Faster version
* of hat_getattr in certain architectures.
*/
int
hat_probe(hat_t *hat, caddr_t addr)
{
uintptr_t vaddr = ALIGN2PAGE(addr);
uint_t entry;
htable_t *ht;
pgcnt_t pg_off;
ASSERT(hat == kas.a_hat || vaddr < kernelbase);
ASSERT(hat == kas.a_hat ||
AS_LOCK_HELD(hat->hat_as, &hat->hat_as->a_lock));
if (IN_VA_HOLE(vaddr))
return (0);
/*
* Most common use of hat_probe is from segmap. We special case it
* for performance.
*/
if (mmu.kmap_addr <= vaddr && vaddr < mmu.kmap_eaddr) {
pg_off = mmu_btop(vaddr - mmu.kmap_addr);
if (mmu.pae_hat)
return (PTE_ISVALID(mmu.kmap_ptes[pg_off]));
else
return (PTE_ISVALID(
((x86pte32_t *)mmu.kmap_ptes)[pg_off]));
}
ht = htable_getpage(hat, vaddr, &entry);
if (ht == NULL)
return (0);
htable_release(ht);
return (1);
}
/*
* Simple implementation of ISM. hat_share() is just like hat_memload_array(),
* except that we use the ism_hat's existing mappings to determine the pages
* and protections to use for this hat. In case we find a properly aligned
* and sized pagetable of 4K mappings, we will attempt to share the pagetable
* itself.
*/
/*ARGSUSED*/
int
hat_share(
hat_t *hat,
caddr_t addr,
hat_t *ism_hat,
caddr_t src_addr,
size_t len, /* almost useless value, see below.. */
uint_t ismszc)
{
uintptr_t vaddr_start = (uintptr_t)addr;
uintptr_t vaddr;
uintptr_t pt_vaddr;
uintptr_t eaddr = vaddr_start + len;
uintptr_t ism_addr_start = (uintptr_t)src_addr;
uintptr_t ism_addr = ism_addr_start;
uintptr_t e_ism_addr = ism_addr + len;
htable_t *ism_ht = NULL;
htable_t *ht;
x86pte_t pte;
page_t *pp;
pfn_t pfn;
level_t l;
pgcnt_t pgcnt;
uint_t prot;
uint_t valid_cnt;
/*
* We might be asked to share an empty DISM hat by as_dup()
*/
ASSERT(hat != kas.a_hat);
ASSERT(eaddr <= kernelbase);
if (!(ism_hat->hat_flags & HAT_SHARED)) {
ASSERT(hat_get_mapped_size(ism_hat) == 0);
return (0);
}
/*
* The SPT segment driver often passes us a size larger than there are
* valid mappings. That's because it rounds the segment size up to a
* large pagesize, even if the actual memory mapped by ism_hat is less.
*/
HATIN(hat_share, hat, addr, len);
ASSERT(IS_PAGEALIGNED(vaddr_start));
ASSERT(IS_PAGEALIGNED(ism_addr_start));
ASSERT(ism_hat->hat_flags & HAT_SHARED);
while (ism_addr < e_ism_addr) {
/*
* use htable_walk to get the next valid ISM mapping
*/
pte = htable_walk(ism_hat, &ism_ht, &ism_addr, e_ism_addr);
if (ism_ht == NULL)
break;
/*
* Find the largest page size we can use, based on the
* ISM mapping size, our address alignment and the remaining
* map length.
*/
vaddr = vaddr_start + (ism_addr - ism_addr_start);
for (l = ism_ht->ht_level; l > 0; --l) {
if (LEVEL_SIZE(l) <= eaddr - vaddr &&
(vaddr & LEVEL_OFFSET(l)) == 0)
break;
}
/*
* attempt to share the pagetable
*
* - only 4K pagetables are shared (ie. level == 0)
* - the hat_share() length must cover the whole pagetable
* - the shared address must align at level 1
* - a shared PTE for this address already exists OR
* - no page table for this address exists yet
*/
pt_vaddr =
vaddr_start + (ism_ht->ht_vaddr - ism_addr_start);
if (ism_ht->ht_level == 0 &&
ism_ht->ht_vaddr + LEVEL_SIZE(1) <= e_ism_addr &&
(pt_vaddr & LEVEL_OFFSET(1)) == 0) {
ht = htable_lookup(hat, pt_vaddr, 0);
if (ht == NULL)
ht = htable_create(hat, pt_vaddr, 0, ism_ht);
if (ht->ht_level > 0 ||
!(ht->ht_flags & HTABLE_SHARED_PFN)) {
htable_release(ht);
} else {
/*
* share the page table
*/
ASSERT(ht->ht_level == 0);
ASSERT(ht->ht_shares == ism_ht);
valid_cnt = ism_ht->ht_valid_cnt;
atomic_add_long(&hat->hat_pages_mapped[0],
valid_cnt - ht->ht_valid_cnt);
ht->ht_valid_cnt = valid_cnt;
htable_release(ht);
ism_addr = ism_ht->ht_vaddr + LEVEL_SIZE(1);
htable_release(ism_ht);
ism_ht = NULL;
continue;
}
}
/*
* Unable to share the page table. Instead we will
* create new mappings from the values in the ISM mappings.
*
* The ISM mapping might be larger than the share area,
* be careful to trunctate it if needed.
*/
if (eaddr - vaddr >= LEVEL_SIZE(ism_ht->ht_level)) {
pgcnt = mmu_btop(LEVEL_SIZE(ism_ht->ht_level));
} else {
pgcnt = mmu_btop(eaddr - vaddr);
l = 0;
}
pfn = PTE2PFN(pte, ism_ht->ht_level);
ASSERT(pfn != PFN_INVALID);
while (pgcnt > 0) {
/*
* Make a new pte for the PFN for this level.
* Copy protections for the pte from the ISM pte.
*/
pp = page_numtopp_nolock(pfn);
ASSERT(pp != NULL);
prot = PROT_USER | PROT_READ | HAT_UNORDERED_OK;
if (PTE_GET(pte, PT_WRITABLE))
prot |= PROT_WRITE;
if (!PTE_GET(pte, PT_NX))
prot |= PROT_EXEC;
/*
* XX64 -- can shm ever be written to swap?
* if not we could use HAT_NOSYNC here.
*/
hati_load_common(hat, vaddr, pp, prot,
HAT_LOAD, l, pfn);
vaddr += LEVEL_SIZE(l);
ism_addr += LEVEL_SIZE(l);
pfn += mmu_btop(LEVEL_SIZE(l));
pgcnt -= mmu_btop(LEVEL_SIZE(l));
}
}
if (ism_ht != NULL)
htable_release(ism_ht);
HATOUT(hat_share, hat, addr);
return (0);
}
/*
* hat_unshare() is similar to hat_unload_callback(), but
* we have to look for empty shared pagetables. Note that
* hat_unshare() is always invoked against an entire segment.
*/
/*ARGSUSED*/
void
hat_unshare(hat_t *hat, caddr_t addr, size_t len, uint_t ismszc)
{
uintptr_t vaddr = (uintptr_t)addr;
uintptr_t eaddr = vaddr + len;
htable_t *ht = NULL;
uint_t need_demaps = 0;
ASSERT(hat != kas.a_hat);
ASSERT(eaddr <= kernelbase);
HATIN(hat_unshare, hat, addr, len);
ASSERT(IS_PAGEALIGNED(vaddr));
ASSERT(IS_PAGEALIGNED(eaddr));
/*
* First go through and remove any shared pagetables.
*
* Note that it's ok to delay the demap until the entire range is
* finished, because if hat_pageunload() were to unload a shared
* pagetable page, its hat_demap() will do a global user TLB invalidate.
*/
while (vaddr < eaddr) {
ASSERT(!IN_VA_HOLE(vaddr));
/*
* find the pagetable that would map the current address
*/
ht = htable_lookup(hat, vaddr, 0);
if (ht != NULL) {
if (ht->ht_flags & HTABLE_SHARED_PFN) {
/*
* clear mapped pages count, set valid_cnt to 0
* and let htable_release() finish the job
*/
atomic_add_long(&hat->hat_pages_mapped[0],
-ht->ht_valid_cnt);
ht->ht_valid_cnt = 0;
need_demaps = 1;
}
htable_release(ht);
}
vaddr = (vaddr & LEVEL_MASK(1)) + LEVEL_SIZE(1);
}
/*
* flush the TLBs - since we're probably dealing with MANY mappings
* we do just one CR3 reload.
*/
if (!(hat->hat_flags & HAT_FREEING) && need_demaps)
hat_demap(hat, DEMAP_ALL_ADDR);
/*
* Now go back and clean up any unaligned mappings that
* couldn't share pagetables.
*/
hat_unload(hat, addr, len, HAT_UNLOAD_UNMAP);
HATOUT(hat_unshare, hat, addr);
}
/*
* hat_reserve() does nothing
*/
/*ARGSUSED*/
void
hat_reserve(struct as *as, caddr_t addr, size_t len)
{
}
/*
* Called when all mappings to a page should have write permission removed.
* Mostly stolem from hat_pagesync()
*/
static void
hati_page_clrwrt(struct page *pp)
{
hment_t *hm = NULL;
htable_t *ht;
uint_t entry;
x86pte_t old;
x86pte_t new;
uint_t pszc = 0;
next_size:
/*
* walk thru the mapping list clearing write permission
*/
x86_hm_enter(pp);
while ((hm = hment_walk(pp, &ht, &entry, hm)) != NULL) {
if (ht->ht_level < pszc)
continue;
old = x86pte_get(ht, entry);
for (;;) {
/*
* Is this mapping of interest?
*/
if (PTE2PFN(old, ht->ht_level) != pp->p_pagenum ||
PTE_GET(old, PT_WRITABLE) == 0)
break;
/*
* Clear ref/mod writable bits. This requires cross
* calls to ensure any executing TLBs see cleared bits.
*/
new = old;
PTE_CLR(new, PT_REF | PT_MOD | PT_WRITABLE);
old = hati_update_pte(ht, entry, old, new);
if (old != 0)
continue;
break;
}
}
x86_hm_exit(pp);
while (pszc < pp->p_szc) {
page_t *tpp;
pszc++;
tpp = PP_GROUPLEADER(pp, pszc);
if (pp != tpp) {
pp = tpp;
goto next_size;
}
}
}
/*
* void hat_page_setattr(pp, flag)
* void hat_page_clrattr(pp, flag)
* used to set/clr ref/mod bits.
*/
void
hat_page_setattr(struct page *pp, uint_t flag)
{
vnode_t *vp = pp->p_vnode;
kmutex_t *vphm = NULL;
page_t **listp;
if (PP_GETRM(pp, flag) == flag)
return;
if ((flag & P_MOD) != 0 && vp != NULL && IS_VMODSORT(vp)) {
vphm = page_vnode_mutex(vp);
mutex_enter(vphm);
}
PP_SETRM(pp, flag);
if (vphm != NULL) {
/*
* Some File Systems examine v_pages for NULL w/o
* grabbing the vphm mutex. Must not let it become NULL when
* pp is the only page on the list.
*/
if (pp->p_vpnext != pp) {
page_vpsub(&vp->v_pages, pp);
if (vp->v_pages != NULL)
listp = &vp->v_pages->p_vpprev->p_vpnext;
else
listp = &vp->v_pages;
page_vpadd(listp, pp);
}
mutex_exit(vphm);
}
}
void
hat_page_clrattr(struct page *pp, uint_t flag)
{
vnode_t *vp = pp->p_vnode;
kmutex_t *vphm = NULL;
ASSERT(!(flag & ~(P_MOD | P_REF | P_RO)));
/*
* for vnode with a sorted v_pages list, we need to change
* the attributes and the v_pages list together under page_vnode_mutex.
*/
if ((flag & P_MOD) != 0 && vp != NULL && IS_VMODSORT(vp)) {
vphm = page_vnode_mutex(vp);
mutex_enter(vphm);
}
PP_CLRRM(pp, flag);
if (vphm != NULL) {
/*
* Some File Systems examine v_pages for NULL w/o
* grabbing the vphm mutex. Must not let it become NULL when
* pp is the only page on the list.
*/
if (pp->p_vpnext != pp) {
page_vpsub(&vp->v_pages, pp);
page_vpadd(&vp->v_pages, pp);
}
mutex_exit(vphm);
/*
* VMODSORT works by removing write permissions and getting
* a fault when a page is made dirty. At this point
* we need to remove write permission from all mappings
* to this page.
*/
hati_page_clrwrt(pp);
}
}
/*
* If flag is specified, returns 0 if attribute is disabled
* and non zero if enabled. If flag specifes multiple attributs
* then returns 0 if ALL atriibutes are disabled. This is an advisory
* call.
*/
uint_t
hat_page_getattr(struct page *pp, uint_t flag)
{
return (PP_GETRM(pp, flag));
}
/*
* common code used by hat_pageunload() and hment_steal()
*/
hment_t *
hati_page_unmap(page_t *pp, htable_t *ht, uint_t entry)
{
x86pte_t old_pte;
pfn_t pfn = pp->p_pagenum;
hment_t *hm;
/*
* We need to acquire a hold on the htable in order to
* do the invalidate. We know the htable must exist, since
* unmap's don't release the htable until after removing any
* hment. Having x86_hm_enter() keeps that from proceeding.
*/
htable_acquire(ht);
/*
* Invalidate the PTE and remove the hment.
*/
old_pte = x86pte_invalidate_pfn(ht, entry, pfn, NULL);
if (PTE2PFN(old_pte, ht->ht_level) != pfn) {
panic("x86pte_invalidate_pfn() failure found PTE = " FMT_PTE
" pfn being unmapped is %lx ht=0x%lx entry=0x%x",
old_pte, pfn, (uintptr_t)ht, entry);
}
/*
* Clean up all the htable information for this mapping
*/
ASSERT(ht->ht_valid_cnt > 0);
HTABLE_DEC(ht->ht_valid_cnt);
PGCNT_DEC(ht->ht_hat, ht->ht_level);
/*
* sync ref/mod bits to the page_t
*/
if (PTE_GET(old_pte, PT_NOSYNC) == 0)
hati_sync_pte_to_page(pp, old_pte, ht->ht_level);
/*
* Remove the mapping list entry for this page.
*/
hm = hment_remove(pp, ht, entry);
/*
* drop the mapping list lock so that we might free the
* hment and htable.
*/
x86_hm_exit(pp);
htable_release(ht);
return (hm);
}
/*
* Unload all translations to a page. If the page is a subpage of a large
* page, the large page mappings are also removed.
*
* The forceflags are unused.
*/
/*ARGSUSED*/
static int
hati_pageunload(struct page *pp, uint_t pg_szcd, uint_t forceflag)
{
page_t *cur_pp = pp;
hment_t *hm;
hment_t *prev;
htable_t *ht;
uint_t entry;
level_t level;
/*
* The loop with next_size handles pages with multiple pagesize mappings
*/
next_size:
for (;;) {
/*
* Get a mapping list entry
*/
x86_hm_enter(cur_pp);
for (prev = NULL; ; prev = hm) {
hm = hment_walk(cur_pp, &ht, &entry, prev);
if (hm == NULL) {
x86_hm_exit(cur_pp);
/*
* If not part of a larger page, we're done.
*/
if (cur_pp->p_szc <= pg_szcd)
return (0);
/*
* Else check the next larger page size.
* hat_page_demote() may decrease p_szc
* but that's ok we'll just take an extra
* trip discover there're no larger mappings
* and return.
*/
++pg_szcd;
cur_pp = PP_GROUPLEADER(cur_pp, pg_szcd);
goto next_size;
}
/*
* If this mapping size matches, remove it.
*/
level = ht->ht_level;
if (level == pg_szcd)
break;
}
/*
* Remove the mapping list entry for this page.
* Note this does the x86_hm_exit() for us.
*/
hm = hati_page_unmap(cur_pp, ht, entry);
if (hm != NULL)
hment_free(hm);
}
}
int
hat_pageunload(struct page *pp, uint_t forceflag)
{
ASSERT(PAGE_EXCL(pp));
return (hati_pageunload(pp, 0, forceflag));
}
/*
* Unload all large mappings to pp and reduce by 1 p_szc field of every large
* page level that included pp.
*
* pp must be locked EXCL. Even though no other constituent pages are locked
* it's legal to unload large mappings to pp because all constituent pages of
* large locked mappings have to be locked SHARED. therefore if we have EXCL
* lock on one of constituent pages none of the large mappings to pp are
* locked.
*
* Change (always decrease) p_szc field starting from the last constituent
* page and ending with root constituent page so that root's pszc always shows
* the area where hat_page_demote() may be active.
*
* This mechanism is only used for file system pages where it's not always
* possible to get EXCL locks on all constituent pages to demote the size code
* (as is done for anonymous or kernel large pages).
*/
void
hat_page_demote(page_t *pp)
{
uint_t pszc;
uint_t rszc;
uint_t szc;
page_t *rootpp;
page_t *firstpp;
page_t *lastpp;
pgcnt_t pgcnt;
ASSERT(PAGE_EXCL(pp));
ASSERT(!PP_ISFREE(pp));
ASSERT(page_szc_lock_assert(pp));
if (pp->p_szc == 0)
return;
rootpp = PP_GROUPLEADER(pp, 1);
(void) hati_pageunload(rootpp, 1, HAT_FORCE_PGUNLOAD);
/*
* all large mappings to pp are gone
* and no new can be setup since pp is locked exclusively.
*
* Lock the root to make sure there's only one hat_page_demote()
* outstanding within the area of this root's pszc.
*
* Second potential hat_page_demote() is already eliminated by upper
* VM layer via page_szc_lock() but we don't rely on it and use our
* own locking (so that upper layer locking can be changed without
* assumptions that hat depends on upper layer VM to prevent multiple
* hat_page_demote() to be issued simultaneously to the same large
* page).
*/
again:
pszc = pp->p_szc;
if (pszc == 0)
return;
rootpp = PP_GROUPLEADER(pp, pszc);
x86_hm_enter(rootpp);
/*
* If root's p_szc is different from pszc we raced with another
* hat_page_demote(). Drop the lock and try to find the root again.
* If root's p_szc is greater than pszc previous hat_page_demote() is
* not done yet. Take and release mlist lock of root's root to wait
* for previous hat_page_demote() to complete.
*/
if ((rszc = rootpp->p_szc) != pszc) {
x86_hm_exit(rootpp);
if (rszc > pszc) {
/* p_szc of a locked non free page can't increase */
ASSERT(pp != rootpp);
rootpp = PP_GROUPLEADER(rootpp, rszc);
x86_hm_enter(rootpp);
x86_hm_exit(rootpp);
}
goto again;
}
ASSERT(pp->p_szc == pszc);
/*
* Decrement by 1 p_szc of every constituent page of a region that
* covered pp. For example if original szc is 3 it gets changed to 2
* everywhere except in region 2 that covered pp. Region 2 that
* covered pp gets demoted to 1 everywhere except in region 1 that
* covered pp. The region 1 that covered pp is demoted to region
* 0. It's done this way because from region 3 we removed level 3
* mappings, from region 2 that covered pp we removed level 2 mappings
* and from region 1 that covered pp we removed level 1 mappings. All
* changes are done from from high pfn's to low pfn's so that roots
* are changed last allowing one to know the largest region where
* hat_page_demote() is stil active by only looking at the root page.
*
* This algorithm is implemented in 2 while loops. First loop changes
* p_szc of pages to the right of pp's level 1 region and second
* loop changes p_szc of pages of level 1 region that covers pp
* and all pages to the left of level 1 region that covers pp.
* In the first loop p_szc keeps dropping with every iteration
* and in the second loop it keeps increasing with every iteration.
*
* First loop description: Demote pages to the right of pp outside of
* level 1 region that covers pp. In every iteration of the while
* loop below find the last page of szc region and the first page of
* (szc - 1) region that is immediately to the right of (szc - 1)
* region that covers pp. From last such page to first such page
* change every page's szc to szc - 1. Decrement szc and continue
* looping until szc is 1. If pp belongs to the last (szc - 1) region
* of szc region skip to the next iteration.
*/
szc = pszc;
while (szc > 1) {
lastpp = PP_GROUPLEADER(pp, szc);
pgcnt = page_get_pagecnt(szc);
lastpp += pgcnt - 1;
firstpp = PP_GROUPLEADER(pp, (szc - 1));
pgcnt = page_get_pagecnt(szc - 1);
if (lastpp - firstpp < pgcnt) {
szc--;
continue;
}
firstpp += pgcnt;
while (lastpp != firstpp) {
ASSERT(lastpp->p_szc == pszc);
lastpp->p_szc = szc - 1;
lastpp--;
}
firstpp->p_szc = szc - 1;
szc--;
}
/*
* Second loop description:
* First iteration changes p_szc to 0 of every
* page of level 1 region that covers pp.
* Subsequent iterations find last page of szc region
* immediately to the left of szc region that covered pp
* and first page of (szc + 1) region that covers pp.
* From last to first page change p_szc of every page to szc.
* Increment szc and continue looping until szc is pszc.
* If pp belongs to the fist szc region of (szc + 1) region
* skip to the next iteration.
*
*/
szc = 0;
while (szc < pszc) {
firstpp = PP_GROUPLEADER(pp, (szc + 1));
if (szc == 0) {
pgcnt = page_get_pagecnt(1);
lastpp = firstpp + (pgcnt - 1);
} else {
lastpp = PP_GROUPLEADER(pp, szc);
if (firstpp == lastpp) {
szc++;
continue;
}
lastpp--;
pgcnt = page_get_pagecnt(szc);
}
while (lastpp != firstpp) {
ASSERT(lastpp->p_szc == pszc);
lastpp->p_szc = szc;
lastpp--;
}
firstpp->p_szc = szc;
if (firstpp == rootpp)
break;
szc++;
}
x86_hm_exit(rootpp);
}
/*
* get hw stats from hardware into page struct and reset hw stats
* returns attributes of page
* Flags for hat_pagesync, hat_getstat, hat_sync
*
* define HAT_SYNC_ZERORM 0x01
*
* Additional flags for hat_pagesync
*
* define HAT_SYNC_STOPON_REF 0x02
* define HAT_SYNC_STOPON_MOD 0x04
* define HAT_SYNC_STOPON_RM 0x06
* define HAT_SYNC_STOPON_SHARED 0x08
*/
uint_t
hat_pagesync(struct page *pp, uint_t flags)
{
hment_t *hm = NULL;
htable_t *ht;
uint_t entry;
x86pte_t old, save_old;
x86pte_t new;
uchar_t nrmbits = P_REF|P_MOD|P_RO;
extern ulong_t po_share;
page_t *save_pp = pp;
uint_t pszc = 0;
ASSERT(PAGE_LOCKED(pp) || panicstr);
if (PP_ISRO(pp) && (flags & HAT_SYNC_STOPON_MOD))
return (pp->p_nrm & nrmbits);
if ((flags & HAT_SYNC_ZERORM) == 0) {
if ((flags & HAT_SYNC_STOPON_REF) != 0 && PP_ISREF(pp))
return (pp->p_nrm & nrmbits);
if ((flags & HAT_SYNC_STOPON_MOD) != 0 && PP_ISMOD(pp))
return (pp->p_nrm & nrmbits);
if ((flags & HAT_SYNC_STOPON_SHARED) != 0 &&
hat_page_getshare(pp) > po_share) {
if (PP_ISRO(pp))
PP_SETREF(pp);
return (pp->p_nrm & nrmbits);
}
}
next_size:
/*
* walk thru the mapping list syncing (and clearing) ref/mod bits.
*/
x86_hm_enter(pp);
while ((hm = hment_walk(pp, &ht, &entry, hm)) != NULL) {
if (ht->ht_level < pszc)
continue;
old = x86pte_get(ht, entry);
try_again:
ASSERT(PTE2PFN(old, ht->ht_level) == pp->p_pagenum);
if (PTE_GET(old, PT_REF | PT_MOD) == 0)
continue;
save_old = old;
if ((flags & HAT_SYNC_ZERORM) != 0) {
/*
* Need to clear ref or mod bits. Need to demap
* to make sure any executing TLBs see cleared bits.
*/
new = old;
PTE_CLR(new, PT_REF | PT_MOD);
old = hati_update_pte(ht, entry, old, new);
if (old != 0)
goto try_again;
old = save_old;
}
/*
* Sync the PTE
*/
if (!(flags & HAT_SYNC_ZERORM) && PTE_GET(old, PT_NOSYNC) == 0)
hati_sync_pte_to_page(pp, old, ht->ht_level);
/*
* can stop short if we found a ref'd or mod'd page
*/
if ((flags & HAT_SYNC_STOPON_MOD) && PP_ISMOD(save_pp) ||
(flags & HAT_SYNC_STOPON_REF) && PP_ISREF(save_pp)) {
x86_hm_exit(pp);
return (save_pp->p_nrm & nrmbits);
}
}
x86_hm_exit(pp);
while (pszc < pp->p_szc) {
page_t *tpp;
pszc++;
tpp = PP_GROUPLEADER(pp, pszc);
if (pp != tpp) {
pp = tpp;
goto next_size;
}
}
return (save_pp->p_nrm & nrmbits);
}
/*
* returns approx number of mappings to this pp. A return of 0 implies
* there are no mappings to the page.
*/
ulong_t
hat_page_getshare(page_t *pp)
{
uint_t cnt;
cnt = hment_mapcnt(pp);
return (cnt);
}
/*
* hat_softlock isn't supported anymore
*/
/*ARGSUSED*/
faultcode_t
hat_softlock(
hat_t *hat,
caddr_t addr,
size_t *len,
struct page **page_array,
uint_t flags)
{
return (FC_NOSUPPORT);
}
/*
* Routine to expose supported HAT features to platform independent code.
*/
/*ARGSUSED*/
int
hat_supported(enum hat_features feature, void *arg)
{
switch (feature) {
case HAT_SHARED_PT: /* this is really ISM */
return (1);
case HAT_DYNAMIC_ISM_UNMAP:
return (0);
case HAT_VMODSORT:
return (1);
default:
panic("hat_supported() - unknown feature");
}
return (0);
}
/*
* Called when a thread is exiting and has been switched to the kernel AS
*/
void
hat_thread_exit(kthread_t *thd)
{
ASSERT(thd->t_procp->p_as == &kas);
hat_switch(thd->t_procp->p_as->a_hat);
}
/*
* Setup the given brand new hat structure as the new HAT on this cpu's mmu.
*/
/*ARGSUSED*/
void
hat_setup(hat_t *hat, int flags)
{
kpreempt_disable();
hat_switch(hat);
kpreempt_enable();
}
/*
* Prepare for a CPU private mapping for the given address.
*
* The address can only be used from a single CPU and can be remapped
* using hat_mempte_remap(). Return the address of the PTE.
*
* We do the htable_create() if necessary and increment the valid count so
* the htable can't disappear. We also hat_devload() the page table into
* kernel so that the PTE is quickly accessed.
*/
void *
hat_mempte_kern_setup(caddr_t addr, void *pt)
{
uintptr_t va = (uintptr_t)addr;
htable_t *ht;
uint_t entry;
x86pte_t oldpte;
caddr_t p = (caddr_t)pt;
ASSERT(IS_PAGEALIGNED(va));
ASSERT(!IN_VA_HOLE(va));
ht = htable_getpte(kas.a_hat, va, &entry, &oldpte, 0);
if (ht == NULL) {
/*
* Note that we don't need a hat_reserves_exit() check
* for this htable_create(), since that'll be done by the
* hat_devload() just below.
*/
ht = htable_create(kas.a_hat, va, 0, NULL);
entry = htable_va2entry(va, ht);
ASSERT(ht->ht_level == 0);
oldpte = x86pte_get(ht, entry);
}
if (PTE_ISVALID(oldpte))
panic("hat_mempte_setup(): address already mapped"
"ht=%p, entry=%d, pte=" FMT_PTE, ht, entry, oldpte);
/*
* increment ht_valid_cnt so that the pagetable can't disappear
*/
HTABLE_INC(ht->ht_valid_cnt);
/*
* now we need to map the page holding the pagetable for va into
* the kernel's address space.
*/
hat_devload(kas.a_hat, p, MMU_PAGESIZE, ht->ht_pfn,
PROT_READ | PROT_WRITE | HAT_NOSYNC | HAT_UNORDERED_OK,
HAT_LOAD | HAT_LOAD_NOCONSIST);
/*
* return the PTE address to the caller.
*/
htable_release(ht);
p += entry << mmu.pte_size_shift;
return ((void *)p);
}
/*
* Prepare for a CPU private mapping for the given address.
*/
void *
hat_mempte_setup(caddr_t addr)
{
x86pte_t *p;
p = vmem_alloc(heap_arena, MMU_PAGESIZE, VM_SLEEP);
return (hat_mempte_kern_setup(addr, p));
}
/*
* Release a CPU private mapping for the given address.
* We decrement the htable valid count so it might be destroyed.
*/
void
hat_mempte_release(caddr_t addr, void *pteptr)
{
htable_t *ht;
uintptr_t va = ALIGN2PAGE(pteptr);
/*
* first invalidate any left over mapping and decrement the
* htable's mapping count
*/
if (mmu.pae_hat)
*(x86pte_t *)pteptr = 0;
else
*(x86pte32_t *)pteptr = 0;
mmu_tlbflush_entry(addr);
ht = htable_getpte(kas.a_hat, ALIGN2PAGE(addr), NULL, NULL, 0);
if (ht == NULL)
panic("hat_mempte_release(): invalid address");
ASSERT(ht->ht_level == 0);
HTABLE_DEC(ht->ht_valid_cnt);
htable_release(ht);
/*
* now blow away the kernel mapping to the page table page
* XX64 -- see comment in hat_mempte_setup()
*/
hat_unload_callback(kas.a_hat, (caddr_t)va, MMU_PAGESIZE,
HAT_UNLOAD, NULL);
}
/*
* Apply a temporary CPU private mapping to a page. We flush the TLB only
* on this CPU, so this ought to have been called with preemption disabled.
*/
void
hat_mempte_remap(
pfn_t pfn,
caddr_t addr,
void *pteptr,
uint_t attr,
uint_t flags)
{
uintptr_t va = (uintptr_t)addr;
x86pte_t pte;
/*
* Remap the given PTE to the new page's PFN. Invalidate only
* on this CPU.
*/
#ifdef DEBUG
htable_t *ht;
uint_t entry;
ASSERT(IS_PAGEALIGNED(va));
ASSERT(!IN_VA_HOLE(va));
ht = htable_getpte(kas.a_hat, va, &entry, NULL, 0);
ASSERT(ht != NULL);
ASSERT(ht->ht_level == 0);
ASSERT(ht->ht_valid_cnt > 0);
htable_release(ht);
#endif
pte = hati_mkpte(pfn, attr, 0, flags);
if (mmu.pae_hat)
*(x86pte_t *)pteptr = pte;
else
*(x86pte32_t *)pteptr = (x86pte32_t)pte;
mmu_tlbflush_entry(addr);
}
/*
* Hat locking functions
* XXX - these two functions are currently being used by hatstats
* they can be removed by using a per-as mutex for hatstats.
*/
void
hat_enter(hat_t *hat)
{
mutex_enter(&hat->hat_mutex);
}
void
hat_exit(hat_t *hat)
{
mutex_exit(&hat->hat_mutex);
}
/*
* Used by hat_kern_setup() to create initial kernel HAT mappings from
* the boot loader's mappings.
*
* - size is either PAGESIZE or some multiple of a level one pagesize
* - there may not be page_t's for every pfn. (ie. the nucleus pages)
* - pfn's are continguous for the given va range (va to va + size * cnt)
*/
void
hati_kern_setup_load(
uintptr_t va, /* starting va of range to map */
size_t size, /* either PAGESIZE or multiple of large page size */
pfn_t pfn, /* starting PFN */
pgcnt_t cnt, /* number of mappings, (cnt * size) == total size */
uint_t prot) /* protections (PROT_READ, PROT_WRITE, PROT_EXEC) */
{
level_t level = (size == MMU_PAGESIZE ? 0 : 1);
size_t bytes = size * cnt;
size_t pgsize = LEVEL_SIZE(level);
page_t *pp;
uint_t flags = HAT_LOAD;
/*
* We're only going to throw away mappings below kernelbase or in
* boot's special double-mapping region, so set noconsist to avoid
* using hments
*/
if (BOOT_VA(va))
flags |= HAT_LOAD_NOCONSIST;
prot |= HAT_STORECACHING_OK;
while (bytes != 0) {
ASSERT(bytes >= pgsize);
pp = NULL;
if (pf_is_memory(pfn) && !BOOT_VA(va) && level == 0)
pp = page_numtopp_nolock(pfn);
hati_load_common(kas.a_hat, va, pp, prot, flags, level, pfn);
va += pgsize;
pfn += mmu_btop(pgsize);
bytes -= pgsize;
}
}
/*
* HAT part of cpu intialization.
*/
void
hat_cpu_online(struct cpu *cpup)
{
if (cpup != CPU) {
x86pte_cpu_init(cpup, NULL);
hat_vlp_setup(cpup);
}
CPUSET_ATOMIC_ADD(khat_cpuset, cpup->cpu_id);
}
/*
* Function called after all CPUs are brought online.
* Used to remove low address boot mappings.
*/
void
clear_boot_mappings(uintptr_t low, uintptr_t high)
{
uintptr_t vaddr = low;
htable_t *ht = NULL;
level_t level;
uint_t entry;
x86pte_t pte;
/*
* On 1st CPU we can unload the prom mappings, basically we blow away
* all virtual mappings under kernelbase.
*/
while (vaddr < high) {
pte = htable_walk(kas.a_hat, &ht, &vaddr, high);
if (ht == NULL)
break;
level = ht->ht_level;
entry = htable_va2entry(vaddr, ht);
ASSERT(level <= mmu.max_page_level);
ASSERT(PTE_ISPAGE(pte, level));
/*
* Unload the mapping from the page tables.
*/
(void) x86pte_set(ht, entry, 0, NULL);
ASSERT(ht->ht_valid_cnt > 0);
HTABLE_DEC(ht->ht_valid_cnt);
PGCNT_DEC(ht->ht_hat, ht->ht_level);
vaddr += LEVEL_SIZE(ht->ht_level);
}
if (ht)
htable_release(ht);
/*
* cross call for a complete invalidate.
*/
hat_demap(kas.a_hat, DEMAP_ALL_ADDR);
}
/*
* Initialize a special area in the kernel that always holds some PTEs for
* faster performance. This always holds segmap's PTEs.
* In the 32 bit kernel this maps the kernel heap too.
*/
void
hat_kmap_init(uintptr_t base, size_t len)
{
uintptr_t map_addr; /* base rounded down to large page size */
uintptr_t map_eaddr; /* base + len rounded up */
size_t map_len;
caddr_t ptes; /* mapping area in kernel as for ptes */
size_t window_size; /* size of mapping area for ptes */
ulong_t htable_cnt; /* # of page tables to cover map_len */
ulong_t i;
htable_t *ht;
/*
* we have to map in an area that matches an entire page table
*/
map_addr = base & LEVEL_MASK(1);
map_eaddr = (base + len + LEVEL_SIZE(1) - 1) & LEVEL_MASK(1);
map_len = map_eaddr - map_addr;
window_size = mmu_btop(map_len) * mmu.pte_size;
htable_cnt = mmu_btop(map_len) / mmu.ptes_per_table;
/*
* allocate vmem for the kmap_ptes
*/
ptes = vmem_xalloc(heap_arena, window_size, MMU_PAGESIZE, 0,
0, NULL, NULL, VM_SLEEP);
mmu.kmap_htables =
kmem_alloc(htable_cnt * sizeof (htable_t *), KM_SLEEP);
/*
* Map the page tables that cover kmap into the allocated range.
* Note we don't ever htable_release() the kmap page tables - they
* can't ever be stolen, freed, etc.
*/
for (i = 0; i < htable_cnt; ++i) {
ht = htable_create(kas.a_hat, map_addr + i * LEVEL_SIZE(1),
0, NULL);
mmu.kmap_htables[i] = ht;
hat_devload(kas.a_hat, ptes + i * MMU_PAGESIZE, MMU_PAGESIZE,
ht->ht_pfn,
PROT_READ | PROT_WRITE | HAT_NOSYNC | HAT_UNORDERED_OK,
HAT_LOAD | HAT_LOAD_NOCONSIST);
}
/*
* set information in mmu to activate handling of kmap
*/
mmu.kmap_addr = base;
mmu.kmap_eaddr = base + len;
mmu.kmap_ptes =
(x86pte_t *)(ptes + mmu.pte_size * mmu_btop(base - map_addr));
}
/*
* Atomically update a new translation for a single page. If the
* currently installed PTE doesn't match the value we expect to find,
* it's not updated and we return the PTE we found.
*
* If activating nosync or NOWRITE and the page was modified we need to sync
* with the page_t. Also sync with page_t if clearing ref/mod bits.
*/
static x86pte_t
hati_update_pte(htable_t *ht, uint_t entry, x86pte_t expected, x86pte_t new)
{
page_t *pp;
uint_t rm = 0;
x86pte_t replaced;
if (!PTE_GET(expected, PT_NOSYNC | PT_NOCONSIST) &&
PTE_GET(expected, PT_MOD | PT_REF) &&
(PTE_GET(new, PT_NOSYNC) || !PTE_GET(new, PT_WRITABLE) ||
!PTE_GET(new, PT_MOD | PT_REF))) {
pp = page_numtopp_nolock(PTE2PFN(expected, ht->ht_level));
ASSERT(pp != NULL);
if (PTE_GET(expected, PT_MOD))
rm |= P_MOD;
if (PTE_GET(expected, PT_REF))
rm |= P_REF;
PTE_CLR(new, PT_MOD | PT_REF);
}
replaced = x86pte_update(ht, entry, expected, new);
if (replaced != expected)
return (replaced);
if (rm) {
/*
* sync to all constituent pages of a large page
*/
pgcnt_t pgcnt = page_get_pagecnt(ht->ht_level);
ASSERT(IS_P2ALIGNED(pp->p_pagenum, pgcnt));
while (pgcnt-- > 0) {
/*
* hat_page_demote() can't decrease
* pszc below this mapping size
* since large mapping existed after we
* took mlist lock.
*/
ASSERT(pp->p_szc >= ht->ht_level);
hat_page_setattr(pp, rm);
++pp;
}
}
return (0);
}
/*
* Kernel Physical Mapping (kpm) facility
*
* Most of the routines needed to support segkpm are almost no-ops on the
* x86 platform. We map in the entire segment when it is created and leave
* it mapped in, so there is no additional work required to set up and tear
* down individual mappings. All of these routines were created to support
* SPARC platforms that have to avoid aliasing in their virtually indexed
* caches.
*
* Most of the routines have sanity checks in them (e.g. verifying that the
* passed-in page is locked). We don't actually care about most of these
* checks on x86, but we leave them in place to identify problems in the
* upper levels.
*/
/*
* Map in a locked page and return the vaddr.
*/
/*ARGSUSED*/
caddr_t
hat_kpm_mapin(struct page *pp, struct kpme *kpme)
{
caddr_t vaddr;
#ifdef DEBUG
if (kpm_enable == 0) {
cmn_err(CE_WARN, "hat_kpm_mapin: kpm_enable not set\n");
return ((caddr_t)NULL);
}
if (pp == NULL || PAGE_LOCKED(pp) == 0) {
cmn_err(CE_WARN, "hat_kpm_mapin: pp zero or not locked\n");
return ((caddr_t)NULL);
}
#endif
vaddr = hat_kpm_page2va(pp, 1);
return (vaddr);
}
/*
* Mapout a locked page.
*/
/*ARGSUSED*/
void
hat_kpm_mapout(struct page *pp, struct kpme *kpme, caddr_t vaddr)
{
#ifdef DEBUG
if (kpm_enable == 0) {
cmn_err(CE_WARN, "hat_kpm_mapout: kpm_enable not set\n");
return;
}
if (IS_KPM_ADDR(vaddr) == 0) {
cmn_err(CE_WARN, "hat_kpm_mapout: no kpm address\n");
return;
}
if (pp == NULL || PAGE_LOCKED(pp) == 0) {
cmn_err(CE_WARN, "hat_kpm_mapout: page zero or not locked\n");
return;
}
#endif
}
/*
* Return the kpm virtual address for a specific pfn
*/
caddr_t
hat_kpm_pfn2va(pfn_t pfn)
{
uintptr_t vaddr;
ASSERT(kpm_enable);
vaddr = (uintptr_t)kpm_vbase + mmu_ptob(pfn);
return ((caddr_t)vaddr);
}
/*
* Return the kpm virtual address for the page at pp.
*/
/*ARGSUSED*/
caddr_t
hat_kpm_page2va(struct page *pp, int checkswap)
{
return (hat_kpm_pfn2va(pp->p_pagenum));
}
/*
* Return the page frame number for the kpm virtual address vaddr.
*/
pfn_t
hat_kpm_va2pfn(caddr_t vaddr)
{
pfn_t pfn;
ASSERT(IS_KPM_ADDR(vaddr));
pfn = (pfn_t)btop(vaddr - kpm_vbase);
return (pfn);
}
/*
* Return the page for the kpm virtual address vaddr.
*/
page_t *
hat_kpm_vaddr2page(caddr_t vaddr)
{
pfn_t pfn;
ASSERT(IS_KPM_ADDR(vaddr));
pfn = hat_kpm_va2pfn(vaddr);
return (page_numtopp_nolock(pfn));
}
/*
* hat_kpm_fault is called from segkpm_fault when we take a page fault on a
* KPM page. This should never happen on x86
*/
int
hat_kpm_fault(hat_t *hat, caddr_t vaddr)
{
panic("pagefault in seg_kpm. hat: 0x%p vaddr: 0x%p", hat, vaddr);
return (0);
}
/*ARGSUSED*/
void
hat_kpm_mseghash_clear(int nentries)
{}
/*ARGSUSED*/
void
hat_kpm_mseghash_update(pgcnt_t inx, struct memseg *msp)
{}