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| Current File : //sys/amd64/compile/hs32/modules/usr/src/sys/modules/xl/@/i386/i386/pmap.c |
/*-
* Copyright (c) 1991 Regents of the University of California.
* All rights reserved.
* Copyright (c) 1994 John S. Dyson
* All rights reserved.
* Copyright (c) 1994 David Greenman
* All rights reserved.
* Copyright (c) 2005-2010 Alan L. Cox <alc@cs.rice.edu>
* All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* the Systems Programming Group of the University of Utah Computer
* Science Department and William Jolitz of UUNET Technologies Inc.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* from: @(#)pmap.c 7.7 (Berkeley) 5/12/91
*/
/*-
* Copyright (c) 2003 Networks Associates Technology, Inc.
* All rights reserved.
*
* This software was developed for the FreeBSD Project by Jake Burkholder,
* Safeport Network Services, and Network Associates Laboratories, the
* Security Research Division of Network Associates, Inc. under
* DARPA/SPAWAR contract N66001-01-C-8035 ("CBOSS"), as part of the DARPA
* CHATS research program.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD: release/9.1.0/sys/i386/i386/pmap.c 238005 2012-07-02 17:22:38Z alc $");
/*
* Manages physical address maps.
*
* In addition to hardware address maps, this
* module is called upon to provide software-use-only
* maps which may or may not be stored in the same
* form as hardware maps. These pseudo-maps are
* used to store intermediate results from copy
* operations to and from address spaces.
*
* Since the information managed by this module is
* also stored by the logical address mapping module,
* this module may throw away valid virtual-to-physical
* mappings at almost any time. However, invalidations
* of virtual-to-physical mappings must be done as
* requested.
*
* In order to cope with hardware architectures which
* make virtual-to-physical map invalidates expensive,
* this module may delay invalidate or reduced protection
* operations until such time as they are actually
* necessary. This module is given full information as
* to which processors are currently using which maps,
* and to when physical maps must be made correct.
*/
#include "opt_cpu.h"
#include "opt_pmap.h"
#include "opt_smp.h"
#include "opt_xbox.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/ktr.h>
#include <sys/lock.h>
#include <sys/malloc.h>
#include <sys/mman.h>
#include <sys/msgbuf.h>
#include <sys/mutex.h>
#include <sys/proc.h>
#include <sys/rwlock.h>
#include <sys/sf_buf.h>
#include <sys/sx.h>
#include <sys/vmmeter.h>
#include <sys/sched.h>
#include <sys/sysctl.h>
#ifdef SMP
#include <sys/smp.h>
#else
#include <sys/cpuset.h>
#endif
#include <vm/vm.h>
#include <vm/vm_param.h>
#include <vm/vm_kern.h>
#include <vm/vm_page.h>
#include <vm/vm_map.h>
#include <vm/vm_object.h>
#include <vm/vm_extern.h>
#include <vm/vm_pageout.h>
#include <vm/vm_pager.h>
#include <vm/vm_reserv.h>
#include <vm/uma.h>
#include <machine/cpu.h>
#include <machine/cputypes.h>
#include <machine/md_var.h>
#include <machine/pcb.h>
#include <machine/specialreg.h>
#ifdef SMP
#include <machine/smp.h>
#endif
#ifdef XBOX
#include <machine/xbox.h>
#endif
#if !defined(CPU_DISABLE_SSE) && defined(I686_CPU)
#define CPU_ENABLE_SSE
#endif
#ifndef PMAP_SHPGPERPROC
#define PMAP_SHPGPERPROC 200
#endif
#if !defined(DIAGNOSTIC)
#ifdef __GNUC_GNU_INLINE__
#define PMAP_INLINE __attribute__((__gnu_inline__)) inline
#else
#define PMAP_INLINE extern inline
#endif
#else
#define PMAP_INLINE
#endif
#ifdef PV_STATS
#define PV_STAT(x) do { x ; } while (0)
#else
#define PV_STAT(x) do { } while (0)
#endif
#define pa_index(pa) ((pa) >> PDRSHIFT)
#define pa_to_pvh(pa) (&pv_table[pa_index(pa)])
/*
* Get PDEs and PTEs for user/kernel address space
*/
#define pmap_pde(m, v) (&((m)->pm_pdir[(vm_offset_t)(v) >> PDRSHIFT]))
#define pdir_pde(m, v) (m[(vm_offset_t)(v) >> PDRSHIFT])
#define pmap_pde_v(pte) ((*(int *)pte & PG_V) != 0)
#define pmap_pte_w(pte) ((*(int *)pte & PG_W) != 0)
#define pmap_pte_m(pte) ((*(int *)pte & PG_M) != 0)
#define pmap_pte_u(pte) ((*(int *)pte & PG_A) != 0)
#define pmap_pte_v(pte) ((*(int *)pte & PG_V) != 0)
#define pmap_pte_set_w(pte, v) ((v) ? atomic_set_int((u_int *)(pte), PG_W) : \
atomic_clear_int((u_int *)(pte), PG_W))
#define pmap_pte_set_prot(pte, v) ((*(int *)pte &= ~PG_PROT), (*(int *)pte |= (v)))
struct pmap kernel_pmap_store;
LIST_HEAD(pmaplist, pmap);
static struct pmaplist allpmaps;
static struct mtx allpmaps_lock;
vm_offset_t virtual_avail; /* VA of first avail page (after kernel bss) */
vm_offset_t virtual_end; /* VA of last avail page (end of kernel AS) */
int pgeflag = 0; /* PG_G or-in */
int pseflag = 0; /* PG_PS or-in */
static int nkpt = NKPT;
vm_offset_t kernel_vm_end = KERNBASE + NKPT * NBPDR;
extern u_int32_t KERNend;
extern u_int32_t KPTphys;
#ifdef PAE
pt_entry_t pg_nx;
static uma_zone_t pdptzone;
#endif
SYSCTL_NODE(_vm, OID_AUTO, pmap, CTLFLAG_RD, 0, "VM/pmap parameters");
static int pat_works = 1;
SYSCTL_INT(_vm_pmap, OID_AUTO, pat_works, CTLFLAG_RD, &pat_works, 1,
"Is page attribute table fully functional?");
static int pg_ps_enabled = 1;
SYSCTL_INT(_vm_pmap, OID_AUTO, pg_ps_enabled, CTLFLAG_RDTUN, &pg_ps_enabled, 0,
"Are large page mappings enabled?");
#define PAT_INDEX_SIZE 8
static int pat_index[PAT_INDEX_SIZE]; /* cache mode to PAT index conversion */
/*
* Isolate the global pv list lock from data and other locks to prevent false
* sharing within the cache.
*/
static struct {
struct rwlock lock;
char padding[CACHE_LINE_SIZE - sizeof(struct rwlock)];
} pvh_global __aligned(CACHE_LINE_SIZE);
#define pvh_global_lock pvh_global.lock
/*
* Data for the pv entry allocation mechanism
*/
static TAILQ_HEAD(pch, pv_chunk) pv_chunks = TAILQ_HEAD_INITIALIZER(pv_chunks);
static int pv_entry_count = 0, pv_entry_max = 0, pv_entry_high_water = 0;
static struct md_page *pv_table;
static int shpgperproc = PMAP_SHPGPERPROC;
struct pv_chunk *pv_chunkbase; /* KVA block for pv_chunks */
int pv_maxchunks; /* How many chunks we have KVA for */
vm_offset_t pv_vafree; /* freelist stored in the PTE */
/*
* All those kernel PT submaps that BSD is so fond of
*/
struct sysmaps {
struct mtx lock;
pt_entry_t *CMAP1;
pt_entry_t *CMAP2;
caddr_t CADDR1;
caddr_t CADDR2;
};
static struct sysmaps sysmaps_pcpu[MAXCPU];
pt_entry_t *CMAP1 = 0;
static pt_entry_t *CMAP3;
static pd_entry_t *KPTD;
caddr_t CADDR1 = 0, ptvmmap = 0;
static caddr_t CADDR3;
struct msgbuf *msgbufp = 0;
/*
* Crashdump maps.
*/
static caddr_t crashdumpmap;
static pt_entry_t *PMAP1 = 0, *PMAP2;
static pt_entry_t *PADDR1 = 0, *PADDR2;
#ifdef SMP
static int PMAP1cpu;
static int PMAP1changedcpu;
SYSCTL_INT(_debug, OID_AUTO, PMAP1changedcpu, CTLFLAG_RD,
&PMAP1changedcpu, 0,
"Number of times pmap_pte_quick changed CPU with same PMAP1");
#endif
static int PMAP1changed;
SYSCTL_INT(_debug, OID_AUTO, PMAP1changed, CTLFLAG_RD,
&PMAP1changed, 0,
"Number of times pmap_pte_quick changed PMAP1");
static int PMAP1unchanged;
SYSCTL_INT(_debug, OID_AUTO, PMAP1unchanged, CTLFLAG_RD,
&PMAP1unchanged, 0,
"Number of times pmap_pte_quick didn't change PMAP1");
static struct mtx PMAP2mutex;
static void free_pv_chunk(struct pv_chunk *pc);
static void free_pv_entry(pmap_t pmap, pv_entry_t pv);
static pv_entry_t get_pv_entry(pmap_t pmap, boolean_t try);
static void pmap_pv_demote_pde(pmap_t pmap, vm_offset_t va, vm_paddr_t pa);
static boolean_t pmap_pv_insert_pde(pmap_t pmap, vm_offset_t va, vm_paddr_t pa);
static void pmap_pv_promote_pde(pmap_t pmap, vm_offset_t va, vm_paddr_t pa);
static void pmap_pvh_free(struct md_page *pvh, pmap_t pmap, vm_offset_t va);
static pv_entry_t pmap_pvh_remove(struct md_page *pvh, pmap_t pmap,
vm_offset_t va);
static int pmap_pvh_wired_mappings(struct md_page *pvh, int count);
static boolean_t pmap_demote_pde(pmap_t pmap, pd_entry_t *pde, vm_offset_t va);
static boolean_t pmap_enter_pde(pmap_t pmap, vm_offset_t va, vm_page_t m,
vm_prot_t prot);
static vm_page_t pmap_enter_quick_locked(pmap_t pmap, vm_offset_t va,
vm_page_t m, vm_prot_t prot, vm_page_t mpte);
static void pmap_flush_page(vm_page_t m);
static void pmap_insert_pt_page(pmap_t pmap, vm_page_t mpte);
static void pmap_fill_ptp(pt_entry_t *firstpte, pt_entry_t newpte);
static boolean_t pmap_is_modified_pvh(struct md_page *pvh);
static boolean_t pmap_is_referenced_pvh(struct md_page *pvh);
static void pmap_kenter_attr(vm_offset_t va, vm_paddr_t pa, int mode);
static void pmap_kenter_pde(vm_offset_t va, pd_entry_t newpde);
static vm_page_t pmap_lookup_pt_page(pmap_t pmap, vm_offset_t va);
static void pmap_pde_attr(pd_entry_t *pde, int cache_bits);
static void pmap_promote_pde(pmap_t pmap, pd_entry_t *pde, vm_offset_t va);
static boolean_t pmap_protect_pde(pmap_t pmap, pd_entry_t *pde, vm_offset_t sva,
vm_prot_t prot);
static void pmap_pte_attr(pt_entry_t *pte, int cache_bits);
static void pmap_remove_pde(pmap_t pmap, pd_entry_t *pdq, vm_offset_t sva,
vm_page_t *free);
static int pmap_remove_pte(pmap_t pmap, pt_entry_t *ptq, vm_offset_t sva,
vm_page_t *free);
static void pmap_remove_pt_page(pmap_t pmap, vm_page_t mpte);
static void pmap_remove_page(struct pmap *pmap, vm_offset_t va,
vm_page_t *free);
static void pmap_remove_entry(struct pmap *pmap, vm_page_t m,
vm_offset_t va);
static void pmap_insert_entry(pmap_t pmap, vm_offset_t va, vm_page_t m);
static boolean_t pmap_try_insert_pv_entry(pmap_t pmap, vm_offset_t va,
vm_page_t m);
static void pmap_update_pde(pmap_t pmap, vm_offset_t va, pd_entry_t *pde,
pd_entry_t newpde);
static void pmap_update_pde_invalidate(vm_offset_t va, pd_entry_t newpde);
static vm_page_t pmap_allocpte(pmap_t pmap, vm_offset_t va, int flags);
static vm_page_t _pmap_allocpte(pmap_t pmap, u_int ptepindex, int flags);
static int _pmap_unwire_pte_hold(pmap_t pmap, vm_page_t m, vm_page_t *free);
static pt_entry_t *pmap_pte_quick(pmap_t pmap, vm_offset_t va);
static void pmap_pte_release(pt_entry_t *pte);
static int pmap_unuse_pt(pmap_t, vm_offset_t, vm_page_t *);
#ifdef PAE
static void *pmap_pdpt_allocf(uma_zone_t zone, int bytes, u_int8_t *flags, int wait);
#endif
static void pmap_set_pg(void);
static __inline void pagezero(void *page);
CTASSERT(1 << PDESHIFT == sizeof(pd_entry_t));
CTASSERT(1 << PTESHIFT == sizeof(pt_entry_t));
/*
* If you get an error here, then you set KVA_PAGES wrong! See the
* description of KVA_PAGES in sys/i386/include/pmap.h. It must be
* multiple of 4 for a normal kernel, or a multiple of 8 for a PAE.
*/
CTASSERT(KERNBASE % (1 << 24) == 0);
/*
* Bootstrap the system enough to run with virtual memory.
*
* On the i386 this is called after mapping has already been enabled
* and just syncs the pmap module with what has already been done.
* [We can't call it easily with mapping off since the kernel is not
* mapped with PA == VA, hence we would have to relocate every address
* from the linked base (virtual) address "KERNBASE" to the actual
* (physical) address starting relative to 0]
*/
void
pmap_bootstrap(vm_paddr_t firstaddr)
{
vm_offset_t va;
pt_entry_t *pte, *unused;
struct sysmaps *sysmaps;
int i;
/*
* Initialize the first available kernel virtual address. However,
* using "firstaddr" may waste a few pages of the kernel virtual
* address space, because locore may not have mapped every physical
* page that it allocated. Preferably, locore would provide a first
* unused virtual address in addition to "firstaddr".
*/
virtual_avail = (vm_offset_t) KERNBASE + firstaddr;
virtual_end = VM_MAX_KERNEL_ADDRESS;
/*
* Initialize the kernel pmap (which is statically allocated).
*/
PMAP_LOCK_INIT(kernel_pmap);
kernel_pmap->pm_pdir = (pd_entry_t *) (KERNBASE + (u_int)IdlePTD);
#ifdef PAE
kernel_pmap->pm_pdpt = (pdpt_entry_t *) (KERNBASE + (u_int)IdlePDPT);
#endif
kernel_pmap->pm_root = NULL;
CPU_FILL(&kernel_pmap->pm_active); /* don't allow deactivation */
TAILQ_INIT(&kernel_pmap->pm_pvchunk);
/*
* Initialize the global pv list lock.
*/
rw_init(&pvh_global_lock, "pvh global");
LIST_INIT(&allpmaps);
/*
* Request a spin mutex so that changes to allpmaps cannot be
* preempted by smp_rendezvous_cpus(). Otherwise,
* pmap_update_pde_kernel() could access allpmaps while it is
* being changed.
*/
mtx_init(&allpmaps_lock, "allpmaps", NULL, MTX_SPIN);
mtx_lock_spin(&allpmaps_lock);
LIST_INSERT_HEAD(&allpmaps, kernel_pmap, pm_list);
mtx_unlock_spin(&allpmaps_lock);
/*
* Reserve some special page table entries/VA space for temporary
* mapping of pages.
*/
#define SYSMAP(c, p, v, n) \
v = (c)va; va += ((n)*PAGE_SIZE); p = pte; pte += (n);
va = virtual_avail;
pte = vtopte(va);
/*
* CMAP1/CMAP2 are used for zeroing and copying pages.
* CMAP3 is used for the idle process page zeroing.
*/
for (i = 0; i < MAXCPU; i++) {
sysmaps = &sysmaps_pcpu[i];
mtx_init(&sysmaps->lock, "SYSMAPS", NULL, MTX_DEF);
SYSMAP(caddr_t, sysmaps->CMAP1, sysmaps->CADDR1, 1)
SYSMAP(caddr_t, sysmaps->CMAP2, sysmaps->CADDR2, 1)
}
SYSMAP(caddr_t, CMAP1, CADDR1, 1)
SYSMAP(caddr_t, CMAP3, CADDR3, 1)
/*
* Crashdump maps.
*/
SYSMAP(caddr_t, unused, crashdumpmap, MAXDUMPPGS)
/*
* ptvmmap is used for reading arbitrary physical pages via /dev/mem.
*/
SYSMAP(caddr_t, unused, ptvmmap, 1)
/*
* msgbufp is used to map the system message buffer.
*/
SYSMAP(struct msgbuf *, unused, msgbufp, atop(round_page(msgbufsize)))
/*
* KPTmap is used by pmap_kextract().
*
* KPTmap is first initialized by locore. However, that initial
* KPTmap can only support NKPT page table pages. Here, a larger
* KPTmap is created that can support KVA_PAGES page table pages.
*/
SYSMAP(pt_entry_t *, KPTD, KPTmap, KVA_PAGES)
for (i = 0; i < NKPT; i++)
KPTD[i] = (KPTphys + (i << PAGE_SHIFT)) | pgeflag | PG_RW | PG_V;
/*
* Adjust the start of the KPTD and KPTmap so that the implementation
* of pmap_kextract() and pmap_growkernel() can be made simpler.
*/
KPTD -= KPTDI;
KPTmap -= i386_btop(KPTDI << PDRSHIFT);
/*
* ptemap is used for pmap_pte_quick
*/
SYSMAP(pt_entry_t *, PMAP1, PADDR1, 1)
SYSMAP(pt_entry_t *, PMAP2, PADDR2, 1)
mtx_init(&PMAP2mutex, "PMAP2", NULL, MTX_DEF);
virtual_avail = va;
/*
* Leave in place an identity mapping (virt == phys) for the low 1 MB
* physical memory region that is used by the ACPI wakeup code. This
* mapping must not have PG_G set.
*/
#ifdef XBOX
/* FIXME: This is gross, but needed for the XBOX. Since we are in such
* an early stadium, we cannot yet neatly map video memory ... :-(
* Better fixes are very welcome! */
if (!arch_i386_is_xbox)
#endif
for (i = 1; i < NKPT; i++)
PTD[i] = 0;
/* Initialize the PAT MSR if present. */
pmap_init_pat();
/* Turn on PG_G on kernel page(s) */
pmap_set_pg();
}
/*
* Setup the PAT MSR.
*/
void
pmap_init_pat(void)
{
int pat_table[PAT_INDEX_SIZE];
uint64_t pat_msr;
u_long cr0, cr4;
int i;
/* Set default PAT index table. */
for (i = 0; i < PAT_INDEX_SIZE; i++)
pat_table[i] = -1;
pat_table[PAT_WRITE_BACK] = 0;
pat_table[PAT_WRITE_THROUGH] = 1;
pat_table[PAT_UNCACHEABLE] = 3;
pat_table[PAT_WRITE_COMBINING] = 3;
pat_table[PAT_WRITE_PROTECTED] = 3;
pat_table[PAT_UNCACHED] = 3;
/* Bail if this CPU doesn't implement PAT. */
if ((cpu_feature & CPUID_PAT) == 0) {
for (i = 0; i < PAT_INDEX_SIZE; i++)
pat_index[i] = pat_table[i];
pat_works = 0;
return;
}
/*
* Due to some Intel errata, we can only safely use the lower 4
* PAT entries.
*
* Intel Pentium III Processor Specification Update
* Errata E.27 (Upper Four PAT Entries Not Usable With Mode B
* or Mode C Paging)
*
* Intel Pentium IV Processor Specification Update
* Errata N46 (PAT Index MSB May Be Calculated Incorrectly)
*/
if (cpu_vendor_id == CPU_VENDOR_INTEL &&
!(CPUID_TO_FAMILY(cpu_id) == 6 && CPUID_TO_MODEL(cpu_id) >= 0xe))
pat_works = 0;
/* Initialize default PAT entries. */
pat_msr = PAT_VALUE(0, PAT_WRITE_BACK) |
PAT_VALUE(1, PAT_WRITE_THROUGH) |
PAT_VALUE(2, PAT_UNCACHED) |
PAT_VALUE(3, PAT_UNCACHEABLE) |
PAT_VALUE(4, PAT_WRITE_BACK) |
PAT_VALUE(5, PAT_WRITE_THROUGH) |
PAT_VALUE(6, PAT_UNCACHED) |
PAT_VALUE(7, PAT_UNCACHEABLE);
if (pat_works) {
/*
* Leave the indices 0-3 at the default of WB, WT, UC-, and UC.
* Program 5 and 6 as WP and WC.
* Leave 4 and 7 as WB and UC.
*/
pat_msr &= ~(PAT_MASK(5) | PAT_MASK(6));
pat_msr |= PAT_VALUE(5, PAT_WRITE_PROTECTED) |
PAT_VALUE(6, PAT_WRITE_COMBINING);
pat_table[PAT_UNCACHED] = 2;
pat_table[PAT_WRITE_PROTECTED] = 5;
pat_table[PAT_WRITE_COMBINING] = 6;
} else {
/*
* Just replace PAT Index 2 with WC instead of UC-.
*/
pat_msr &= ~PAT_MASK(2);
pat_msr |= PAT_VALUE(2, PAT_WRITE_COMBINING);
pat_table[PAT_WRITE_COMBINING] = 2;
}
/* Disable PGE. */
cr4 = rcr4();
load_cr4(cr4 & ~CR4_PGE);
/* Disable caches (CD = 1, NW = 0). */
cr0 = rcr0();
load_cr0((cr0 & ~CR0_NW) | CR0_CD);
/* Flushes caches and TLBs. */
wbinvd();
invltlb();
/* Update PAT and index table. */
wrmsr(MSR_PAT, pat_msr);
for (i = 0; i < PAT_INDEX_SIZE; i++)
pat_index[i] = pat_table[i];
/* Flush caches and TLBs again. */
wbinvd();
invltlb();
/* Restore caches and PGE. */
load_cr0(cr0);
load_cr4(cr4);
}
/*
* Set PG_G on kernel pages. Only the BSP calls this when SMP is turned on.
*/
static void
pmap_set_pg(void)
{
pt_entry_t *pte;
vm_offset_t va, endva;
if (pgeflag == 0)
return;
endva = KERNBASE + KERNend;
if (pseflag) {
va = KERNBASE + KERNLOAD;
while (va < endva) {
pdir_pde(PTD, va) |= pgeflag;
invltlb(); /* Play it safe, invltlb() every time */
va += NBPDR;
}
} else {
va = (vm_offset_t)btext;
while (va < endva) {
pte = vtopte(va);
if (*pte)
*pte |= pgeflag;
invltlb(); /* Play it safe, invltlb() every time */
va += PAGE_SIZE;
}
}
}
/*
* Initialize a vm_page's machine-dependent fields.
*/
void
pmap_page_init(vm_page_t m)
{
TAILQ_INIT(&m->md.pv_list);
m->md.pat_mode = PAT_WRITE_BACK;
}
#ifdef PAE
static void *
pmap_pdpt_allocf(uma_zone_t zone, int bytes, u_int8_t *flags, int wait)
{
/* Inform UMA that this allocator uses kernel_map/object. */
*flags = UMA_SLAB_KERNEL;
return ((void *)kmem_alloc_contig(kernel_map, bytes, wait, 0x0ULL,
0xffffffffULL, 1, 0, VM_MEMATTR_DEFAULT));
}
#endif
/*
* ABuse the pte nodes for unmapped kva to thread a kva freelist through.
* Requirements:
* - Must deal with pages in order to ensure that none of the PG_* bits
* are ever set, PG_V in particular.
* - Assumes we can write to ptes without pte_store() atomic ops, even
* on PAE systems. This should be ok.
* - Assumes nothing will ever test these addresses for 0 to indicate
* no mapping instead of correctly checking PG_V.
* - Assumes a vm_offset_t will fit in a pte (true for i386).
* Because PG_V is never set, there can be no mappings to invalidate.
*/
static vm_offset_t
pmap_ptelist_alloc(vm_offset_t *head)
{
pt_entry_t *pte;
vm_offset_t va;
va = *head;
if (va == 0)
return (va); /* Out of memory */
pte = vtopte(va);
*head = *pte;
if (*head & PG_V)
panic("pmap_ptelist_alloc: va with PG_V set!");
*pte = 0;
return (va);
}
static void
pmap_ptelist_free(vm_offset_t *head, vm_offset_t va)
{
pt_entry_t *pte;
if (va & PG_V)
panic("pmap_ptelist_free: freeing va with PG_V set!");
pte = vtopte(va);
*pte = *head; /* virtual! PG_V is 0 though */
*head = va;
}
static void
pmap_ptelist_init(vm_offset_t *head, void *base, int npages)
{
int i;
vm_offset_t va;
*head = 0;
for (i = npages - 1; i >= 0; i--) {
va = (vm_offset_t)base + i * PAGE_SIZE;
pmap_ptelist_free(head, va);
}
}
/*
* Initialize the pmap module.
* Called by vm_init, to initialize any structures that the pmap
* system needs to map virtual memory.
*/
void
pmap_init(void)
{
vm_page_t mpte;
vm_size_t s;
int i, pv_npg;
/*
* Initialize the vm page array entries for the kernel pmap's
* page table pages.
*/
for (i = 0; i < NKPT; i++) {
mpte = PHYS_TO_VM_PAGE(KPTphys + (i << PAGE_SHIFT));
KASSERT(mpte >= vm_page_array &&
mpte < &vm_page_array[vm_page_array_size],
("pmap_init: page table page is out of range"));
mpte->pindex = i + KPTDI;
mpte->phys_addr = KPTphys + (i << PAGE_SHIFT);
}
/*
* Initialize the address space (zone) for the pv entries. Set a
* high water mark so that the system can recover from excessive
* numbers of pv entries.
*/
TUNABLE_INT_FETCH("vm.pmap.shpgperproc", &shpgperproc);
pv_entry_max = shpgperproc * maxproc + cnt.v_page_count;
TUNABLE_INT_FETCH("vm.pmap.pv_entries", &pv_entry_max);
pv_entry_max = roundup(pv_entry_max, _NPCPV);
pv_entry_high_water = 9 * (pv_entry_max / 10);
/*
* If the kernel is running in a virtual machine on an AMD Family 10h
* processor, then it must assume that MCA is enabled by the virtual
* machine monitor.
*/
if (vm_guest == VM_GUEST_VM && cpu_vendor_id == CPU_VENDOR_AMD &&
CPUID_TO_FAMILY(cpu_id) == 0x10)
workaround_erratum383 = 1;
/*
* Are large page mappings supported and enabled?
*/
TUNABLE_INT_FETCH("vm.pmap.pg_ps_enabled", &pg_ps_enabled);
if (pseflag == 0)
pg_ps_enabled = 0;
else if (pg_ps_enabled) {
KASSERT(MAXPAGESIZES > 1 && pagesizes[1] == 0,
("pmap_init: can't assign to pagesizes[1]"));
pagesizes[1] = NBPDR;
}
/*
* Calculate the size of the pv head table for superpages.
*/
for (i = 0; phys_avail[i + 1]; i += 2);
pv_npg = round_4mpage(phys_avail[(i - 2) + 1]) / NBPDR;
/*
* Allocate memory for the pv head table for superpages.
*/
s = (vm_size_t)(pv_npg * sizeof(struct md_page));
s = round_page(s);
pv_table = (struct md_page *)kmem_alloc(kernel_map, s);
for (i = 0; i < pv_npg; i++)
TAILQ_INIT(&pv_table[i].pv_list);
pv_maxchunks = MAX(pv_entry_max / _NPCPV, maxproc);
pv_chunkbase = (struct pv_chunk *)kmem_alloc_nofault(kernel_map,
PAGE_SIZE * pv_maxchunks);
if (pv_chunkbase == NULL)
panic("pmap_init: not enough kvm for pv chunks");
pmap_ptelist_init(&pv_vafree, pv_chunkbase, pv_maxchunks);
#ifdef PAE
pdptzone = uma_zcreate("PDPT", NPGPTD * sizeof(pdpt_entry_t), NULL,
NULL, NULL, NULL, (NPGPTD * sizeof(pdpt_entry_t)) - 1,
UMA_ZONE_VM | UMA_ZONE_NOFREE);
uma_zone_set_allocf(pdptzone, pmap_pdpt_allocf);
#endif
}
SYSCTL_INT(_vm_pmap, OID_AUTO, pv_entry_max, CTLFLAG_RD, &pv_entry_max, 0,
"Max number of PV entries");
SYSCTL_INT(_vm_pmap, OID_AUTO, shpgperproc, CTLFLAG_RD, &shpgperproc, 0,
"Page share factor per proc");
SYSCTL_NODE(_vm_pmap, OID_AUTO, pde, CTLFLAG_RD, 0,
"2/4MB page mapping counters");
static u_long pmap_pde_demotions;
SYSCTL_ULONG(_vm_pmap_pde, OID_AUTO, demotions, CTLFLAG_RD,
&pmap_pde_demotions, 0, "2/4MB page demotions");
static u_long pmap_pde_mappings;
SYSCTL_ULONG(_vm_pmap_pde, OID_AUTO, mappings, CTLFLAG_RD,
&pmap_pde_mappings, 0, "2/4MB page mappings");
static u_long pmap_pde_p_failures;
SYSCTL_ULONG(_vm_pmap_pde, OID_AUTO, p_failures, CTLFLAG_RD,
&pmap_pde_p_failures, 0, "2/4MB page promotion failures");
static u_long pmap_pde_promotions;
SYSCTL_ULONG(_vm_pmap_pde, OID_AUTO, promotions, CTLFLAG_RD,
&pmap_pde_promotions, 0, "2/4MB page promotions");
/***************************************************
* Low level helper routines.....
***************************************************/
/*
* Determine the appropriate bits to set in a PTE or PDE for a specified
* caching mode.
*/
int
pmap_cache_bits(int mode, boolean_t is_pde)
{
int cache_bits, pat_flag, pat_idx;
if (mode < 0 || mode >= PAT_INDEX_SIZE || pat_index[mode] < 0)
panic("Unknown caching mode %d\n", mode);
/* The PAT bit is different for PTE's and PDE's. */
pat_flag = is_pde ? PG_PDE_PAT : PG_PTE_PAT;
/* Map the caching mode to a PAT index. */
pat_idx = pat_index[mode];
/* Map the 3-bit index value into the PAT, PCD, and PWT bits. */
cache_bits = 0;
if (pat_idx & 0x4)
cache_bits |= pat_flag;
if (pat_idx & 0x2)
cache_bits |= PG_NC_PCD;
if (pat_idx & 0x1)
cache_bits |= PG_NC_PWT;
return (cache_bits);
}
/*
* The caller is responsible for maintaining TLB consistency.
*/
static void
pmap_kenter_pde(vm_offset_t va, pd_entry_t newpde)
{
pd_entry_t *pde;
pmap_t pmap;
boolean_t PTD_updated;
PTD_updated = FALSE;
mtx_lock_spin(&allpmaps_lock);
LIST_FOREACH(pmap, &allpmaps, pm_list) {
if ((pmap->pm_pdir[PTDPTDI] & PG_FRAME) == (PTDpde[0] &
PG_FRAME))
PTD_updated = TRUE;
pde = pmap_pde(pmap, va);
pde_store(pde, newpde);
}
mtx_unlock_spin(&allpmaps_lock);
KASSERT(PTD_updated,
("pmap_kenter_pde: current page table is not in allpmaps"));
}
/*
* After changing the page size for the specified virtual address in the page
* table, flush the corresponding entries from the processor's TLB. Only the
* calling processor's TLB is affected.
*
* The calling thread must be pinned to a processor.
*/
static void
pmap_update_pde_invalidate(vm_offset_t va, pd_entry_t newpde)
{
u_long cr4;
if ((newpde & PG_PS) == 0)
/* Demotion: flush a specific 2MB page mapping. */
invlpg(va);
else if ((newpde & PG_G) == 0)
/*
* Promotion: flush every 4KB page mapping from the TLB
* because there are too many to flush individually.
*/
invltlb();
else {
/*
* Promotion: flush every 4KB page mapping from the TLB,
* including any global (PG_G) mappings.
*/
cr4 = rcr4();
load_cr4(cr4 & ~CR4_PGE);
/*
* Although preemption at this point could be detrimental to
* performance, it would not lead to an error. PG_G is simply
* ignored if CR4.PGE is clear. Moreover, in case this block
* is re-entered, the load_cr4() either above or below will
* modify CR4.PGE flushing the TLB.
*/
load_cr4(cr4 | CR4_PGE);
}
}
#ifdef SMP
/*
* For SMP, these functions have to use the IPI mechanism for coherence.
*
* N.B.: Before calling any of the following TLB invalidation functions,
* the calling processor must ensure that all stores updating a non-
* kernel page table are globally performed. Otherwise, another
* processor could cache an old, pre-update entry without being
* invalidated. This can happen one of two ways: (1) The pmap becomes
* active on another processor after its pm_active field is checked by
* one of the following functions but before a store updating the page
* table is globally performed. (2) The pmap becomes active on another
* processor before its pm_active field is checked but due to
* speculative loads one of the following functions stills reads the
* pmap as inactive on the other processor.
*
* The kernel page table is exempt because its pm_active field is
* immutable. The kernel page table is always active on every
* processor.
*/
void
pmap_invalidate_page(pmap_t pmap, vm_offset_t va)
{
cpuset_t other_cpus;
u_int cpuid;
sched_pin();
if (pmap == kernel_pmap || !CPU_CMP(&pmap->pm_active, &all_cpus)) {
invlpg(va);
smp_invlpg(va);
} else {
cpuid = PCPU_GET(cpuid);
other_cpus = all_cpus;
CPU_CLR(cpuid, &other_cpus);
if (CPU_ISSET(cpuid, &pmap->pm_active))
invlpg(va);
CPU_AND(&other_cpus, &pmap->pm_active);
if (!CPU_EMPTY(&other_cpus))
smp_masked_invlpg(other_cpus, va);
}
sched_unpin();
}
void
pmap_invalidate_range(pmap_t pmap, vm_offset_t sva, vm_offset_t eva)
{
cpuset_t other_cpus;
vm_offset_t addr;
u_int cpuid;
sched_pin();
if (pmap == kernel_pmap || !CPU_CMP(&pmap->pm_active, &all_cpus)) {
for (addr = sva; addr < eva; addr += PAGE_SIZE)
invlpg(addr);
smp_invlpg_range(sva, eva);
} else {
cpuid = PCPU_GET(cpuid);
other_cpus = all_cpus;
CPU_CLR(cpuid, &other_cpus);
if (CPU_ISSET(cpuid, &pmap->pm_active))
for (addr = sva; addr < eva; addr += PAGE_SIZE)
invlpg(addr);
CPU_AND(&other_cpus, &pmap->pm_active);
if (!CPU_EMPTY(&other_cpus))
smp_masked_invlpg_range(other_cpus, sva, eva);
}
sched_unpin();
}
void
pmap_invalidate_all(pmap_t pmap)
{
cpuset_t other_cpus;
u_int cpuid;
sched_pin();
if (pmap == kernel_pmap || !CPU_CMP(&pmap->pm_active, &all_cpus)) {
invltlb();
smp_invltlb();
} else {
cpuid = PCPU_GET(cpuid);
other_cpus = all_cpus;
CPU_CLR(cpuid, &other_cpus);
if (CPU_ISSET(cpuid, &pmap->pm_active))
invltlb();
CPU_AND(&other_cpus, &pmap->pm_active);
if (!CPU_EMPTY(&other_cpus))
smp_masked_invltlb(other_cpus);
}
sched_unpin();
}
void
pmap_invalidate_cache(void)
{
sched_pin();
wbinvd();
smp_cache_flush();
sched_unpin();
}
struct pde_action {
cpuset_t invalidate; /* processors that invalidate their TLB */
vm_offset_t va;
pd_entry_t *pde;
pd_entry_t newpde;
u_int store; /* processor that updates the PDE */
};
static void
pmap_update_pde_kernel(void *arg)
{
struct pde_action *act = arg;
pd_entry_t *pde;
pmap_t pmap;
if (act->store == PCPU_GET(cpuid)) {
/*
* Elsewhere, this operation requires allpmaps_lock for
* synchronization. Here, it does not because it is being
* performed in the context of an all_cpus rendezvous.
*/
LIST_FOREACH(pmap, &allpmaps, pm_list) {
pde = pmap_pde(pmap, act->va);
pde_store(pde, act->newpde);
}
}
}
static void
pmap_update_pde_user(void *arg)
{
struct pde_action *act = arg;
if (act->store == PCPU_GET(cpuid))
pde_store(act->pde, act->newpde);
}
static void
pmap_update_pde_teardown(void *arg)
{
struct pde_action *act = arg;
if (CPU_ISSET(PCPU_GET(cpuid), &act->invalidate))
pmap_update_pde_invalidate(act->va, act->newpde);
}
/*
* Change the page size for the specified virtual address in a way that
* prevents any possibility of the TLB ever having two entries that map the
* same virtual address using different page sizes. This is the recommended
* workaround for Erratum 383 on AMD Family 10h processors. It prevents a
* machine check exception for a TLB state that is improperly diagnosed as a
* hardware error.
*/
static void
pmap_update_pde(pmap_t pmap, vm_offset_t va, pd_entry_t *pde, pd_entry_t newpde)
{
struct pde_action act;
cpuset_t active, other_cpus;
u_int cpuid;
sched_pin();
cpuid = PCPU_GET(cpuid);
other_cpus = all_cpus;
CPU_CLR(cpuid, &other_cpus);
if (pmap == kernel_pmap)
active = all_cpus;
else
active = pmap->pm_active;
if (CPU_OVERLAP(&active, &other_cpus)) {
act.store = cpuid;
act.invalidate = active;
act.va = va;
act.pde = pde;
act.newpde = newpde;
CPU_SET(cpuid, &active);
smp_rendezvous_cpus(active,
smp_no_rendevous_barrier, pmap == kernel_pmap ?
pmap_update_pde_kernel : pmap_update_pde_user,
pmap_update_pde_teardown, &act);
} else {
if (pmap == kernel_pmap)
pmap_kenter_pde(va, newpde);
else
pde_store(pde, newpde);
if (CPU_ISSET(cpuid, &active))
pmap_update_pde_invalidate(va, newpde);
}
sched_unpin();
}
#else /* !SMP */
/*
* Normal, non-SMP, 486+ invalidation functions.
* We inline these within pmap.c for speed.
*/
PMAP_INLINE void
pmap_invalidate_page(pmap_t pmap, vm_offset_t va)
{
if (pmap == kernel_pmap || !CPU_EMPTY(&pmap->pm_active))
invlpg(va);
}
PMAP_INLINE void
pmap_invalidate_range(pmap_t pmap, vm_offset_t sva, vm_offset_t eva)
{
vm_offset_t addr;
if (pmap == kernel_pmap || !CPU_EMPTY(&pmap->pm_active))
for (addr = sva; addr < eva; addr += PAGE_SIZE)
invlpg(addr);
}
PMAP_INLINE void
pmap_invalidate_all(pmap_t pmap)
{
if (pmap == kernel_pmap || !CPU_EMPTY(&pmap->pm_active))
invltlb();
}
PMAP_INLINE void
pmap_invalidate_cache(void)
{
wbinvd();
}
static void
pmap_update_pde(pmap_t pmap, vm_offset_t va, pd_entry_t *pde, pd_entry_t newpde)
{
if (pmap == kernel_pmap)
pmap_kenter_pde(va, newpde);
else
pde_store(pde, newpde);
if (pmap == kernel_pmap || !CPU_EMPTY(&pmap->pm_active))
pmap_update_pde_invalidate(va, newpde);
}
#endif /* !SMP */
#define PMAP_CLFLUSH_THRESHOLD (2 * 1024 * 1024)
void
pmap_invalidate_cache_range(vm_offset_t sva, vm_offset_t eva)
{
KASSERT((sva & PAGE_MASK) == 0,
("pmap_invalidate_cache_range: sva not page-aligned"));
KASSERT((eva & PAGE_MASK) == 0,
("pmap_invalidate_cache_range: eva not page-aligned"));
if (cpu_feature & CPUID_SS)
; /* If "Self Snoop" is supported, do nothing. */
else if ((cpu_feature & CPUID_CLFSH) != 0 &&
eva - sva < PMAP_CLFLUSH_THRESHOLD) {
/*
* Otherwise, do per-cache line flush. Use the mfence
* instruction to insure that previous stores are
* included in the write-back. The processor
* propagates flush to other processors in the cache
* coherence domain.
*/
mfence();
for (; sva < eva; sva += cpu_clflush_line_size)
clflush(sva);
mfence();
} else {
/*
* No targeted cache flush methods are supported by CPU,
* or the supplied range is bigger than 2MB.
* Globally invalidate cache.
*/
pmap_invalidate_cache();
}
}
void
pmap_invalidate_cache_pages(vm_page_t *pages, int count)
{
int i;
if (count >= PMAP_CLFLUSH_THRESHOLD / PAGE_SIZE ||
(cpu_feature & CPUID_CLFSH) == 0) {
pmap_invalidate_cache();
} else {
for (i = 0; i < count; i++)
pmap_flush_page(pages[i]);
}
}
/*
* Are we current address space or kernel? N.B. We return FALSE when
* a pmap's page table is in use because a kernel thread is borrowing
* it. The borrowed page table can change spontaneously, making any
* dependence on its continued use subject to a race condition.
*/
static __inline int
pmap_is_current(pmap_t pmap)
{
return (pmap == kernel_pmap ||
(pmap == vmspace_pmap(curthread->td_proc->p_vmspace) &&
(pmap->pm_pdir[PTDPTDI] & PG_FRAME) == (PTDpde[0] & PG_FRAME)));
}
/*
* If the given pmap is not the current or kernel pmap, the returned pte must
* be released by passing it to pmap_pte_release().
*/
pt_entry_t *
pmap_pte(pmap_t pmap, vm_offset_t va)
{
pd_entry_t newpf;
pd_entry_t *pde;
pde = pmap_pde(pmap, va);
if (*pde & PG_PS)
return (pde);
if (*pde != 0) {
/* are we current address space or kernel? */
if (pmap_is_current(pmap))
return (vtopte(va));
mtx_lock(&PMAP2mutex);
newpf = *pde & PG_FRAME;
if ((*PMAP2 & PG_FRAME) != newpf) {
*PMAP2 = newpf | PG_RW | PG_V | PG_A | PG_M;
pmap_invalidate_page(kernel_pmap, (vm_offset_t)PADDR2);
}
return (PADDR2 + (i386_btop(va) & (NPTEPG - 1)));
}
return (NULL);
}
/*
* Releases a pte that was obtained from pmap_pte(). Be prepared for the pte
* being NULL.
*/
static __inline void
pmap_pte_release(pt_entry_t *pte)
{
if ((pt_entry_t *)((vm_offset_t)pte & ~PAGE_MASK) == PADDR2)
mtx_unlock(&PMAP2mutex);
}
static __inline void
invlcaddr(void *caddr)
{
invlpg((u_int)caddr);
}
/*
* Super fast pmap_pte routine best used when scanning
* the pv lists. This eliminates many coarse-grained
* invltlb calls. Note that many of the pv list
* scans are across different pmaps. It is very wasteful
* to do an entire invltlb for checking a single mapping.
*
* If the given pmap is not the current pmap, pvh_global_lock
* must be held and curthread pinned to a CPU.
*/
static pt_entry_t *
pmap_pte_quick(pmap_t pmap, vm_offset_t va)
{
pd_entry_t newpf;
pd_entry_t *pde;
pde = pmap_pde(pmap, va);
if (*pde & PG_PS)
return (pde);
if (*pde != 0) {
/* are we current address space or kernel? */
if (pmap_is_current(pmap))
return (vtopte(va));
rw_assert(&pvh_global_lock, RA_WLOCKED);
KASSERT(curthread->td_pinned > 0, ("curthread not pinned"));
newpf = *pde & PG_FRAME;
if ((*PMAP1 & PG_FRAME) != newpf) {
*PMAP1 = newpf | PG_RW | PG_V | PG_A | PG_M;
#ifdef SMP
PMAP1cpu = PCPU_GET(cpuid);
#endif
invlcaddr(PADDR1);
PMAP1changed++;
} else
#ifdef SMP
if (PMAP1cpu != PCPU_GET(cpuid)) {
PMAP1cpu = PCPU_GET(cpuid);
invlcaddr(PADDR1);
PMAP1changedcpu++;
} else
#endif
PMAP1unchanged++;
return (PADDR1 + (i386_btop(va) & (NPTEPG - 1)));
}
return (0);
}
/*
* Routine: pmap_extract
* Function:
* Extract the physical page address associated
* with the given map/virtual_address pair.
*/
vm_paddr_t
pmap_extract(pmap_t pmap, vm_offset_t va)
{
vm_paddr_t rtval;
pt_entry_t *pte;
pd_entry_t pde;
rtval = 0;
PMAP_LOCK(pmap);
pde = pmap->pm_pdir[va >> PDRSHIFT];
if (pde != 0) {
if ((pde & PG_PS) != 0)
rtval = (pde & PG_PS_FRAME) | (va & PDRMASK);
else {
pte = pmap_pte(pmap, va);
rtval = (*pte & PG_FRAME) | (va & PAGE_MASK);
pmap_pte_release(pte);
}
}
PMAP_UNLOCK(pmap);
return (rtval);
}
/*
* Routine: pmap_extract_and_hold
* Function:
* Atomically extract and hold the physical page
* with the given pmap and virtual address pair
* if that mapping permits the given protection.
*/
vm_page_t
pmap_extract_and_hold(pmap_t pmap, vm_offset_t va, vm_prot_t prot)
{
pd_entry_t pde;
pt_entry_t pte, *ptep;
vm_page_t m;
vm_paddr_t pa;
pa = 0;
m = NULL;
PMAP_LOCK(pmap);
retry:
pde = *pmap_pde(pmap, va);
if (pde != 0) {
if (pde & PG_PS) {
if ((pde & PG_RW) || (prot & VM_PROT_WRITE) == 0) {
if (vm_page_pa_tryrelock(pmap, (pde &
PG_PS_FRAME) | (va & PDRMASK), &pa))
goto retry;
m = PHYS_TO_VM_PAGE((pde & PG_PS_FRAME) |
(va & PDRMASK));
vm_page_hold(m);
}
} else {
ptep = pmap_pte(pmap, va);
pte = *ptep;
pmap_pte_release(ptep);
if (pte != 0 &&
((pte & PG_RW) || (prot & VM_PROT_WRITE) == 0)) {
if (vm_page_pa_tryrelock(pmap, pte & PG_FRAME,
&pa))
goto retry;
m = PHYS_TO_VM_PAGE(pte & PG_FRAME);
vm_page_hold(m);
}
}
}
PA_UNLOCK_COND(pa);
PMAP_UNLOCK(pmap);
return (m);
}
/***************************************************
* Low level mapping routines.....
***************************************************/
/*
* Add a wired page to the kva.
* Note: not SMP coherent.
*
* This function may be used before pmap_bootstrap() is called.
*/
PMAP_INLINE void
pmap_kenter(vm_offset_t va, vm_paddr_t pa)
{
pt_entry_t *pte;
pte = vtopte(va);
pte_store(pte, pa | PG_RW | PG_V | pgeflag);
}
static __inline void
pmap_kenter_attr(vm_offset_t va, vm_paddr_t pa, int mode)
{
pt_entry_t *pte;
pte = vtopte(va);
pte_store(pte, pa | PG_RW | PG_V | pgeflag | pmap_cache_bits(mode, 0));
}
/*
* Remove a page from the kernel pagetables.
* Note: not SMP coherent.
*
* This function may be used before pmap_bootstrap() is called.
*/
PMAP_INLINE void
pmap_kremove(vm_offset_t va)
{
pt_entry_t *pte;
pte = vtopte(va);
pte_clear(pte);
}
/*
* Used to map a range of physical addresses into kernel
* virtual address space.
*
* The value passed in '*virt' is a suggested virtual address for
* the mapping. Architectures which can support a direct-mapped
* physical to virtual region can return the appropriate address
* within that region, leaving '*virt' unchanged. Other
* architectures should map the pages starting at '*virt' and
* update '*virt' with the first usable address after the mapped
* region.
*/
vm_offset_t
pmap_map(vm_offset_t *virt, vm_paddr_t start, vm_paddr_t end, int prot)
{
vm_offset_t va, sva;
vm_paddr_t superpage_offset;
pd_entry_t newpde;
va = *virt;
/*
* Does the physical address range's size and alignment permit at
* least one superpage mapping to be created?
*/
superpage_offset = start & PDRMASK;
if ((end - start) - ((NBPDR - superpage_offset) & PDRMASK) >= NBPDR) {
/*
* Increase the starting virtual address so that its alignment
* does not preclude the use of superpage mappings.
*/
if ((va & PDRMASK) < superpage_offset)
va = (va & ~PDRMASK) + superpage_offset;
else if ((va & PDRMASK) > superpage_offset)
va = ((va + PDRMASK) & ~PDRMASK) + superpage_offset;
}
sva = va;
while (start < end) {
if ((start & PDRMASK) == 0 && end - start >= NBPDR &&
pseflag) {
KASSERT((va & PDRMASK) == 0,
("pmap_map: misaligned va %#x", va));
newpde = start | PG_PS | pgeflag | PG_RW | PG_V;
pmap_kenter_pde(va, newpde);
va += NBPDR;
start += NBPDR;
} else {
pmap_kenter(va, start);
va += PAGE_SIZE;
start += PAGE_SIZE;
}
}
pmap_invalidate_range(kernel_pmap, sva, va);
*virt = va;
return (sva);
}
/*
* Add a list of wired pages to the kva
* this routine is only used for temporary
* kernel mappings that do not need to have
* page modification or references recorded.
* Note that old mappings are simply written
* over. The page *must* be wired.
* Note: SMP coherent. Uses a ranged shootdown IPI.
*/
void
pmap_qenter(vm_offset_t sva, vm_page_t *ma, int count)
{
pt_entry_t *endpte, oldpte, pa, *pte;
vm_page_t m;
oldpte = 0;
pte = vtopte(sva);
endpte = pte + count;
while (pte < endpte) {
m = *ma++;
pa = VM_PAGE_TO_PHYS(m) | pmap_cache_bits(m->md.pat_mode, 0);
if ((*pte & (PG_FRAME | PG_PTE_CACHE)) != pa) {
oldpte |= *pte;
pte_store(pte, pa | pgeflag | PG_RW | PG_V);
}
pte++;
}
if (__predict_false((oldpte & PG_V) != 0))
pmap_invalidate_range(kernel_pmap, sva, sva + count *
PAGE_SIZE);
}
/*
* This routine tears out page mappings from the
* kernel -- it is meant only for temporary mappings.
* Note: SMP coherent. Uses a ranged shootdown IPI.
*/
void
pmap_qremove(vm_offset_t sva, int count)
{
vm_offset_t va;
va = sva;
while (count-- > 0) {
pmap_kremove(va);
va += PAGE_SIZE;
}
pmap_invalidate_range(kernel_pmap, sva, va);
}
/***************************************************
* Page table page management routines.....
***************************************************/
static __inline void
pmap_free_zero_pages(vm_page_t free)
{
vm_page_t m;
while (free != NULL) {
m = free;
free = m->right;
/* Preserve the page's PG_ZERO setting. */
vm_page_free_toq(m);
}
}
/*
* Schedule the specified unused page table page to be freed. Specifically,
* add the page to the specified list of pages that will be released to the
* physical memory manager after the TLB has been updated.
*/
static __inline void
pmap_add_delayed_free_list(vm_page_t m, vm_page_t *free, boolean_t set_PG_ZERO)
{
if (set_PG_ZERO)
m->flags |= PG_ZERO;
else
m->flags &= ~PG_ZERO;
m->right = *free;
*free = m;
}
/*
* Inserts the specified page table page into the specified pmap's collection
* of idle page table pages. Each of a pmap's page table pages is responsible
* for mapping a distinct range of virtual addresses. The pmap's collection is
* ordered by this virtual address range.
*/
static void
pmap_insert_pt_page(pmap_t pmap, vm_page_t mpte)
{
vm_page_t root;
PMAP_LOCK_ASSERT(pmap, MA_OWNED);
root = pmap->pm_root;
if (root == NULL) {
mpte->left = NULL;
mpte->right = NULL;
} else {
root = vm_page_splay(mpte->pindex, root);
if (mpte->pindex < root->pindex) {
mpte->left = root->left;
mpte->right = root;
root->left = NULL;
} else if (mpte->pindex == root->pindex)
panic("pmap_insert_pt_page: pindex already inserted");
else {
mpte->right = root->right;
mpte->left = root;
root->right = NULL;
}
}
pmap->pm_root = mpte;
}
/*
* Looks for a page table page mapping the specified virtual address in the
* specified pmap's collection of idle page table pages. Returns NULL if there
* is no page table page corresponding to the specified virtual address.
*/
static vm_page_t
pmap_lookup_pt_page(pmap_t pmap, vm_offset_t va)
{
vm_page_t mpte;
vm_pindex_t pindex = va >> PDRSHIFT;
PMAP_LOCK_ASSERT(pmap, MA_OWNED);
if ((mpte = pmap->pm_root) != NULL && mpte->pindex != pindex) {
mpte = vm_page_splay(pindex, mpte);
if ((pmap->pm_root = mpte)->pindex != pindex)
mpte = NULL;
}
return (mpte);
}
/*
* Removes the specified page table page from the specified pmap's collection
* of idle page table pages. The specified page table page must be a member of
* the pmap's collection.
*/
static void
pmap_remove_pt_page(pmap_t pmap, vm_page_t mpte)
{
vm_page_t root;
PMAP_LOCK_ASSERT(pmap, MA_OWNED);
if (mpte != pmap->pm_root)
vm_page_splay(mpte->pindex, pmap->pm_root);
if (mpte->left == NULL)
root = mpte->right;
else {
root = vm_page_splay(mpte->pindex, mpte->left);
root->right = mpte->right;
}
pmap->pm_root = root;
}
/*
* This routine unholds page table pages, and if the hold count
* drops to zero, then it decrements the wire count.
*/
static __inline int
pmap_unwire_pte_hold(pmap_t pmap, vm_page_t m, vm_page_t *free)
{
--m->wire_count;
if (m->wire_count == 0)
return (_pmap_unwire_pte_hold(pmap, m, free));
else
return (0);
}
static int
_pmap_unwire_pte_hold(pmap_t pmap, vm_page_t m, vm_page_t *free)
{
vm_offset_t pteva;
/*
* unmap the page table page
*/
pmap->pm_pdir[m->pindex] = 0;
--pmap->pm_stats.resident_count;
/*
* This is a release store so that the ordinary store unmapping
* the page table page is globally performed before TLB shoot-
* down is begun.
*/
atomic_subtract_rel_int(&cnt.v_wire_count, 1);
/*
* Do an invltlb to make the invalidated mapping
* take effect immediately.
*/
pteva = VM_MAXUSER_ADDRESS + i386_ptob(m->pindex);
pmap_invalidate_page(pmap, pteva);
/*
* Put page on a list so that it is released after
* *ALL* TLB shootdown is done
*/
pmap_add_delayed_free_list(m, free, TRUE);
return (1);
}
/*
* After removing a page table entry, this routine is used to
* conditionally free the page, and manage the hold/wire counts.
*/
static int
pmap_unuse_pt(pmap_t pmap, vm_offset_t va, vm_page_t *free)
{
pd_entry_t ptepde;
vm_page_t mpte;
if (va >= VM_MAXUSER_ADDRESS)
return (0);
ptepde = *pmap_pde(pmap, va);
mpte = PHYS_TO_VM_PAGE(ptepde & PG_FRAME);
return (pmap_unwire_pte_hold(pmap, mpte, free));
}
/*
* Initialize the pmap for the swapper process.
*/
void
pmap_pinit0(pmap_t pmap)
{
PMAP_LOCK_INIT(pmap);
/*
* Since the page table directory is shared with the kernel pmap,
* which is already included in the list "allpmaps", this pmap does
* not need to be inserted into that list.
*/
pmap->pm_pdir = (pd_entry_t *)(KERNBASE + (vm_offset_t)IdlePTD);
#ifdef PAE
pmap->pm_pdpt = (pdpt_entry_t *)(KERNBASE + (vm_offset_t)IdlePDPT);
#endif
pmap->pm_root = NULL;
CPU_ZERO(&pmap->pm_active);
PCPU_SET(curpmap, pmap);
TAILQ_INIT(&pmap->pm_pvchunk);
bzero(&pmap->pm_stats, sizeof pmap->pm_stats);
}
/*
* Initialize a preallocated and zeroed pmap structure,
* such as one in a vmspace structure.
*/
int
pmap_pinit(pmap_t pmap)
{
vm_page_t m, ptdpg[NPGPTD];
vm_paddr_t pa;
int i;
PMAP_LOCK_INIT(pmap);
/*
* No need to allocate page table space yet but we do need a valid
* page directory table.
*/
if (pmap->pm_pdir == NULL) {
pmap->pm_pdir = (pd_entry_t *)kmem_alloc_nofault(kernel_map,
NBPTD);
if (pmap->pm_pdir == NULL) {
PMAP_LOCK_DESTROY(pmap);
return (0);
}
#ifdef PAE
pmap->pm_pdpt = uma_zalloc(pdptzone, M_WAITOK | M_ZERO);
KASSERT(((vm_offset_t)pmap->pm_pdpt &
((NPGPTD * sizeof(pdpt_entry_t)) - 1)) == 0,
("pmap_pinit: pdpt misaligned"));
KASSERT(pmap_kextract((vm_offset_t)pmap->pm_pdpt) < (4ULL<<30),
("pmap_pinit: pdpt above 4g"));
#endif
pmap->pm_root = NULL;
}
KASSERT(pmap->pm_root == NULL,
("pmap_pinit: pmap has reserved page table page(s)"));
/*
* allocate the page directory page(s)
*/
for (i = 0; i < NPGPTD;) {
m = vm_page_alloc(NULL, 0, VM_ALLOC_NORMAL | VM_ALLOC_NOOBJ |
VM_ALLOC_WIRED | VM_ALLOC_ZERO);
if (m == NULL)
VM_WAIT;
else {
ptdpg[i++] = m;
}
}
pmap_qenter((vm_offset_t)pmap->pm_pdir, ptdpg, NPGPTD);
for (i = 0; i < NPGPTD; i++)
if ((ptdpg[i]->flags & PG_ZERO) == 0)
pagezero(pmap->pm_pdir + (i * NPDEPG));
mtx_lock_spin(&allpmaps_lock);
LIST_INSERT_HEAD(&allpmaps, pmap, pm_list);
/* Copy the kernel page table directory entries. */
bcopy(PTD + KPTDI, pmap->pm_pdir + KPTDI, nkpt * sizeof(pd_entry_t));
mtx_unlock_spin(&allpmaps_lock);
/* install self-referential address mapping entry(s) */
for (i = 0; i < NPGPTD; i++) {
pa = VM_PAGE_TO_PHYS(ptdpg[i]);
pmap->pm_pdir[PTDPTDI + i] = pa | PG_V | PG_RW | PG_A | PG_M;
#ifdef PAE
pmap->pm_pdpt[i] = pa | PG_V;
#endif
}
CPU_ZERO(&pmap->pm_active);
TAILQ_INIT(&pmap->pm_pvchunk);
bzero(&pmap->pm_stats, sizeof pmap->pm_stats);
return (1);
}
/*
* this routine is called if the page table page is not
* mapped correctly.
*/
static vm_page_t
_pmap_allocpte(pmap_t pmap, u_int ptepindex, int flags)
{
vm_paddr_t ptepa;
vm_page_t m;
KASSERT((flags & (M_NOWAIT | M_WAITOK)) == M_NOWAIT ||
(flags & (M_NOWAIT | M_WAITOK)) == M_WAITOK,
("_pmap_allocpte: flags is neither M_NOWAIT nor M_WAITOK"));
/*
* Allocate a page table page.
*/
if ((m = vm_page_alloc(NULL, ptepindex, VM_ALLOC_NOOBJ |
VM_ALLOC_WIRED | VM_ALLOC_ZERO)) == NULL) {
if (flags & M_WAITOK) {
PMAP_UNLOCK(pmap);
rw_wunlock(&pvh_global_lock);
VM_WAIT;
rw_wlock(&pvh_global_lock);
PMAP_LOCK(pmap);
}
/*
* Indicate the need to retry. While waiting, the page table
* page may have been allocated.
*/
return (NULL);
}
if ((m->flags & PG_ZERO) == 0)
pmap_zero_page(m);
/*
* Map the pagetable page into the process address space, if
* it isn't already there.
*/
pmap->pm_stats.resident_count++;
ptepa = VM_PAGE_TO_PHYS(m);
pmap->pm_pdir[ptepindex] =
(pd_entry_t) (ptepa | PG_U | PG_RW | PG_V | PG_A | PG_M);
return (m);
}
static vm_page_t
pmap_allocpte(pmap_t pmap, vm_offset_t va, int flags)
{
u_int ptepindex;
pd_entry_t ptepa;
vm_page_t m;
KASSERT((flags & (M_NOWAIT | M_WAITOK)) == M_NOWAIT ||
(flags & (M_NOWAIT | M_WAITOK)) == M_WAITOK,
("pmap_allocpte: flags is neither M_NOWAIT nor M_WAITOK"));
/*
* Calculate pagetable page index
*/
ptepindex = va >> PDRSHIFT;
retry:
/*
* Get the page directory entry
*/
ptepa = pmap->pm_pdir[ptepindex];
/*
* This supports switching from a 4MB page to a
* normal 4K page.
*/
if (ptepa & PG_PS) {
(void)pmap_demote_pde(pmap, &pmap->pm_pdir[ptepindex], va);
ptepa = pmap->pm_pdir[ptepindex];
}
/*
* If the page table page is mapped, we just increment the
* hold count, and activate it.
*/
if (ptepa) {
m = PHYS_TO_VM_PAGE(ptepa & PG_FRAME);
m->wire_count++;
} else {
/*
* Here if the pte page isn't mapped, or if it has
* been deallocated.
*/
m = _pmap_allocpte(pmap, ptepindex, flags);
if (m == NULL && (flags & M_WAITOK))
goto retry;
}
return (m);
}
/***************************************************
* Pmap allocation/deallocation routines.
***************************************************/
#ifdef SMP
/*
* Deal with a SMP shootdown of other users of the pmap that we are
* trying to dispose of. This can be a bit hairy.
*/
static cpuset_t *lazymask;
static u_int lazyptd;
static volatile u_int lazywait;
void pmap_lazyfix_action(void);
void
pmap_lazyfix_action(void)
{
#ifdef COUNT_IPIS
(*ipi_lazypmap_counts[PCPU_GET(cpuid)])++;
#endif
if (rcr3() == lazyptd)
load_cr3(PCPU_GET(curpcb)->pcb_cr3);
CPU_CLR_ATOMIC(PCPU_GET(cpuid), lazymask);
atomic_store_rel_int(&lazywait, 1);
}
static void
pmap_lazyfix_self(u_int cpuid)
{
if (rcr3() == lazyptd)
load_cr3(PCPU_GET(curpcb)->pcb_cr3);
CPU_CLR_ATOMIC(cpuid, lazymask);
}
static void
pmap_lazyfix(pmap_t pmap)
{
cpuset_t mymask, mask;
u_int cpuid, spins;
int lsb;
mask = pmap->pm_active;
while (!CPU_EMPTY(&mask)) {
spins = 50000000;
/* Find least significant set bit. */
lsb = cpusetobj_ffs(&mask);
MPASS(lsb != 0);
lsb--;
CPU_SETOF(lsb, &mask);
mtx_lock_spin(&smp_ipi_mtx);
#ifdef PAE
lazyptd = vtophys(pmap->pm_pdpt);
#else
lazyptd = vtophys(pmap->pm_pdir);
#endif
cpuid = PCPU_GET(cpuid);
/* Use a cpuset just for having an easy check. */
CPU_SETOF(cpuid, &mymask);
if (!CPU_CMP(&mask, &mymask)) {
lazymask = &pmap->pm_active;
pmap_lazyfix_self(cpuid);
} else {
atomic_store_rel_int((u_int *)&lazymask,
(u_int)&pmap->pm_active);
atomic_store_rel_int(&lazywait, 0);
ipi_selected(mask, IPI_LAZYPMAP);
while (lazywait == 0) {
ia32_pause();
if (--spins == 0)
break;
}
}
mtx_unlock_spin(&smp_ipi_mtx);
if (spins == 0)
printf("pmap_lazyfix: spun for 50000000\n");
mask = pmap->pm_active;
}
}
#else /* SMP */
/*
* Cleaning up on uniprocessor is easy. For various reasons, we're
* unlikely to have to even execute this code, including the fact
* that the cleanup is deferred until the parent does a wait(2), which
* means that another userland process has run.
*/
static void
pmap_lazyfix(pmap_t pmap)
{
u_int cr3;
cr3 = vtophys(pmap->pm_pdir);
if (cr3 == rcr3()) {
load_cr3(PCPU_GET(curpcb)->pcb_cr3);
CPU_CLR(PCPU_GET(cpuid), &pmap->pm_active);
}
}
#endif /* SMP */
/*
* Release any resources held by the given physical map.
* Called when a pmap initialized by pmap_pinit is being released.
* Should only be called if the map contains no valid mappings.
*/
void
pmap_release(pmap_t pmap)
{
vm_page_t m, ptdpg[NPGPTD];
int i;
KASSERT(pmap->pm_stats.resident_count == 0,
("pmap_release: pmap resident count %ld != 0",
pmap->pm_stats.resident_count));
KASSERT(pmap->pm_root == NULL,
("pmap_release: pmap has reserved page table page(s)"));
pmap_lazyfix(pmap);
mtx_lock_spin(&allpmaps_lock);
LIST_REMOVE(pmap, pm_list);
mtx_unlock_spin(&allpmaps_lock);
for (i = 0; i < NPGPTD; i++)
ptdpg[i] = PHYS_TO_VM_PAGE(pmap->pm_pdir[PTDPTDI + i] &
PG_FRAME);
bzero(pmap->pm_pdir + PTDPTDI, (nkpt + NPGPTD) *
sizeof(*pmap->pm_pdir));
pmap_qremove((vm_offset_t)pmap->pm_pdir, NPGPTD);
for (i = 0; i < NPGPTD; i++) {
m = ptdpg[i];
#ifdef PAE
KASSERT(VM_PAGE_TO_PHYS(m) == (pmap->pm_pdpt[i] & PG_FRAME),
("pmap_release: got wrong ptd page"));
#endif
m->wire_count--;
atomic_subtract_int(&cnt.v_wire_count, 1);
vm_page_free_zero(m);
}
PMAP_LOCK_DESTROY(pmap);
}
static int
kvm_size(SYSCTL_HANDLER_ARGS)
{
unsigned long ksize = VM_MAX_KERNEL_ADDRESS - KERNBASE;
return (sysctl_handle_long(oidp, &ksize, 0, req));
}
SYSCTL_PROC(_vm, OID_AUTO, kvm_size, CTLTYPE_LONG|CTLFLAG_RD,
0, 0, kvm_size, "IU", "Size of KVM");
static int
kvm_free(SYSCTL_HANDLER_ARGS)
{
unsigned long kfree = VM_MAX_KERNEL_ADDRESS - kernel_vm_end;
return (sysctl_handle_long(oidp, &kfree, 0, req));
}
SYSCTL_PROC(_vm, OID_AUTO, kvm_free, CTLTYPE_LONG|CTLFLAG_RD,
0, 0, kvm_free, "IU", "Amount of KVM free");
/*
* grow the number of kernel page table entries, if needed
*/
void
pmap_growkernel(vm_offset_t addr)
{
vm_paddr_t ptppaddr;
vm_page_t nkpg;
pd_entry_t newpdir;
mtx_assert(&kernel_map->system_mtx, MA_OWNED);
addr = roundup2(addr, NBPDR);
if (addr - 1 >= kernel_map->max_offset)
addr = kernel_map->max_offset;
while (kernel_vm_end < addr) {
if (pdir_pde(PTD, kernel_vm_end)) {
kernel_vm_end = (kernel_vm_end + NBPDR) & ~PDRMASK;
if (kernel_vm_end - 1 >= kernel_map->max_offset) {
kernel_vm_end = kernel_map->max_offset;
break;
}
continue;
}
nkpg = vm_page_alloc(NULL, kernel_vm_end >> PDRSHIFT,
VM_ALLOC_INTERRUPT | VM_ALLOC_NOOBJ | VM_ALLOC_WIRED |
VM_ALLOC_ZERO);
if (nkpg == NULL)
panic("pmap_growkernel: no memory to grow kernel");
nkpt++;
if ((nkpg->flags & PG_ZERO) == 0)
pmap_zero_page(nkpg);
ptppaddr = VM_PAGE_TO_PHYS(nkpg);
newpdir = (pd_entry_t) (ptppaddr | PG_V | PG_RW | PG_A | PG_M);
pdir_pde(KPTD, kernel_vm_end) = pgeflag | newpdir;
pmap_kenter_pde(kernel_vm_end, newpdir);
kernel_vm_end = (kernel_vm_end + NBPDR) & ~PDRMASK;
if (kernel_vm_end - 1 >= kernel_map->max_offset) {
kernel_vm_end = kernel_map->max_offset;
break;
}
}
}
/***************************************************
* page management routines.
***************************************************/
CTASSERT(sizeof(struct pv_chunk) == PAGE_SIZE);
CTASSERT(_NPCM == 11);
CTASSERT(_NPCPV == 336);
static __inline struct pv_chunk *
pv_to_chunk(pv_entry_t pv)
{
return ((struct pv_chunk *)((uintptr_t)pv & ~(uintptr_t)PAGE_MASK));
}
#define PV_PMAP(pv) (pv_to_chunk(pv)->pc_pmap)
#define PC_FREE0_9 0xfffffffful /* Free values for index 0 through 9 */
#define PC_FREE10 0x0000fffful /* Free values for index 10 */
static const uint32_t pc_freemask[_NPCM] = {
PC_FREE0_9, PC_FREE0_9, PC_FREE0_9,
PC_FREE0_9, PC_FREE0_9, PC_FREE0_9,
PC_FREE0_9, PC_FREE0_9, PC_FREE0_9,
PC_FREE0_9, PC_FREE10
};
SYSCTL_INT(_vm_pmap, OID_AUTO, pv_entry_count, CTLFLAG_RD, &pv_entry_count, 0,
"Current number of pv entries");
#ifdef PV_STATS
static int pc_chunk_count, pc_chunk_allocs, pc_chunk_frees, pc_chunk_tryfail;
SYSCTL_INT(_vm_pmap, OID_AUTO, pc_chunk_count, CTLFLAG_RD, &pc_chunk_count, 0,
"Current number of pv entry chunks");
SYSCTL_INT(_vm_pmap, OID_AUTO, pc_chunk_allocs, CTLFLAG_RD, &pc_chunk_allocs, 0,
"Current number of pv entry chunks allocated");
SYSCTL_INT(_vm_pmap, OID_AUTO, pc_chunk_frees, CTLFLAG_RD, &pc_chunk_frees, 0,
"Current number of pv entry chunks frees");
SYSCTL_INT(_vm_pmap, OID_AUTO, pc_chunk_tryfail, CTLFLAG_RD, &pc_chunk_tryfail, 0,
"Number of times tried to get a chunk page but failed.");
static long pv_entry_frees, pv_entry_allocs;
static int pv_entry_spare;
SYSCTL_LONG(_vm_pmap, OID_AUTO, pv_entry_frees, CTLFLAG_RD, &pv_entry_frees, 0,
"Current number of pv entry frees");
SYSCTL_LONG(_vm_pmap, OID_AUTO, pv_entry_allocs, CTLFLAG_RD, &pv_entry_allocs, 0,
"Current number of pv entry allocs");
SYSCTL_INT(_vm_pmap, OID_AUTO, pv_entry_spare, CTLFLAG_RD, &pv_entry_spare, 0,
"Current number of spare pv entries");
#endif
/*
* We are in a serious low memory condition. Resort to
* drastic measures to free some pages so we can allocate
* another pv entry chunk.
*/
static vm_page_t
pmap_pv_reclaim(pmap_t locked_pmap)
{
struct pch newtail;
struct pv_chunk *pc;
struct md_page *pvh;
pd_entry_t *pde;
pmap_t pmap;
pt_entry_t *pte, tpte;
pv_entry_t pv;
vm_offset_t va;
vm_page_t free, m, m_pc;
uint32_t inuse;
int bit, field, freed;
PMAP_LOCK_ASSERT(locked_pmap, MA_OWNED);
pmap = NULL;
free = m_pc = NULL;
TAILQ_INIT(&newtail);
sched_pin();
while ((pc = TAILQ_FIRST(&pv_chunks)) != NULL && (pv_vafree == 0 ||
free == NULL)) {
TAILQ_REMOVE(&pv_chunks, pc, pc_lru);
if (pmap != pc->pc_pmap) {
if (pmap != NULL) {
pmap_invalidate_all(pmap);
if (pmap != locked_pmap)
PMAP_UNLOCK(pmap);
}
pmap = pc->pc_pmap;
/* Avoid deadlock and lock recursion. */
if (pmap > locked_pmap)
PMAP_LOCK(pmap);
else if (pmap != locked_pmap && !PMAP_TRYLOCK(pmap)) {
pmap = NULL;
TAILQ_INSERT_TAIL(&newtail, pc, pc_lru);
continue;
}
}
/*
* Destroy every non-wired, 4 KB page mapping in the chunk.
*/
freed = 0;
for (field = 0; field < _NPCM; field++) {
for (inuse = ~pc->pc_map[field] & pc_freemask[field];
inuse != 0; inuse &= ~(1UL << bit)) {
bit = bsfl(inuse);
pv = &pc->pc_pventry[field * 32 + bit];
va = pv->pv_va;
pde = pmap_pde(pmap, va);
if ((*pde & PG_PS) != 0)
continue;
pte = pmap_pte_quick(pmap, va);
if ((*pte & PG_W) != 0)
continue;
tpte = pte_load_clear(pte);
if ((tpte & PG_G) != 0)
pmap_invalidate_page(pmap, va);
m = PHYS_TO_VM_PAGE(tpte & PG_FRAME);
if ((tpte & (PG_M | PG_RW)) == (PG_M | PG_RW))
vm_page_dirty(m);
if ((tpte & PG_A) != 0)
vm_page_aflag_set(m, PGA_REFERENCED);
TAILQ_REMOVE(&m->md.pv_list, pv, pv_list);
if (TAILQ_EMPTY(&m->md.pv_list) &&
(m->flags & PG_FICTITIOUS) == 0) {
pvh = pa_to_pvh(VM_PAGE_TO_PHYS(m));
if (TAILQ_EMPTY(&pvh->pv_list)) {
vm_page_aflag_clear(m,
PGA_WRITEABLE);
}
}
pc->pc_map[field] |= 1UL << bit;
pmap_unuse_pt(pmap, va, &free);
freed++;
}
}
if (freed == 0) {
TAILQ_INSERT_TAIL(&newtail, pc, pc_lru);
continue;
}
/* Every freed mapping is for a 4 KB page. */
pmap->pm_stats.resident_count -= freed;
PV_STAT(pv_entry_frees += freed);
PV_STAT(pv_entry_spare += freed);
pv_entry_count -= freed;
TAILQ_REMOVE(&pmap->pm_pvchunk, pc, pc_list);
for (field = 0; field < _NPCM; field++)
if (pc->pc_map[field] != pc_freemask[field]) {
TAILQ_INSERT_HEAD(&pmap->pm_pvchunk, pc,
pc_list);
TAILQ_INSERT_TAIL(&newtail, pc, pc_lru);
/*
* One freed pv entry in locked_pmap is
* sufficient.
*/
if (pmap == locked_pmap)
goto out;
break;
}
if (field == _NPCM) {
PV_STAT(pv_entry_spare -= _NPCPV);
PV_STAT(pc_chunk_count--);
PV_STAT(pc_chunk_frees++);
/* Entire chunk is free; return it. */
m_pc = PHYS_TO_VM_PAGE(pmap_kextract((vm_offset_t)pc));
pmap_qremove((vm_offset_t)pc, 1);
pmap_ptelist_free(&pv_vafree, (vm_offset_t)pc);
break;
}
}
out:
sched_unpin();
TAILQ_CONCAT(&pv_chunks, &newtail, pc_lru);
if (pmap != NULL) {
pmap_invalidate_all(pmap);
if (pmap != locked_pmap)
PMAP_UNLOCK(pmap);
}
if (m_pc == NULL && pv_vafree != 0 && free != NULL) {
m_pc = free;
free = m_pc->right;
/* Recycle a freed page table page. */
m_pc->wire_count = 1;
atomic_add_int(&cnt.v_wire_count, 1);
}
pmap_free_zero_pages(free);
return (m_pc);
}
/*
* free the pv_entry back to the free list
*/
static void
free_pv_entry(pmap_t pmap, pv_entry_t pv)
{
struct pv_chunk *pc;
int idx, field, bit;
rw_assert(&pvh_global_lock, RA_WLOCKED);
PMAP_LOCK_ASSERT(pmap, MA_OWNED);
PV_STAT(pv_entry_frees++);
PV_STAT(pv_entry_spare++);
pv_entry_count--;
pc = pv_to_chunk(pv);
idx = pv - &pc->pc_pventry[0];
field = idx / 32;
bit = idx % 32;
pc->pc_map[field] |= 1ul << bit;
for (idx = 0; idx < _NPCM; idx++)
if (pc->pc_map[idx] != pc_freemask[idx]) {
/*
* 98% of the time, pc is already at the head of the
* list. If it isn't already, move it to the head.
*/
if (__predict_false(TAILQ_FIRST(&pmap->pm_pvchunk) !=
pc)) {
TAILQ_REMOVE(&pmap->pm_pvchunk, pc, pc_list);
TAILQ_INSERT_HEAD(&pmap->pm_pvchunk, pc,
pc_list);
}
return;
}
TAILQ_REMOVE(&pmap->pm_pvchunk, pc, pc_list);
free_pv_chunk(pc);
}
static void
free_pv_chunk(struct pv_chunk *pc)
{
vm_page_t m;
TAILQ_REMOVE(&pv_chunks, pc, pc_lru);
PV_STAT(pv_entry_spare -= _NPCPV);
PV_STAT(pc_chunk_count--);
PV_STAT(pc_chunk_frees++);
/* entire chunk is free, return it */
m = PHYS_TO_VM_PAGE(pmap_kextract((vm_offset_t)pc));
pmap_qremove((vm_offset_t)pc, 1);
vm_page_unwire(m, 0);
vm_page_free(m);
pmap_ptelist_free(&pv_vafree, (vm_offset_t)pc);
}
/*
* get a new pv_entry, allocating a block from the system
* when needed.
*/
static pv_entry_t
get_pv_entry(pmap_t pmap, boolean_t try)
{
static const struct timeval printinterval = { 60, 0 };
static struct timeval lastprint;
int bit, field;
pv_entry_t pv;
struct pv_chunk *pc;
vm_page_t m;
rw_assert(&pvh_global_lock, RA_WLOCKED);
PMAP_LOCK_ASSERT(pmap, MA_OWNED);
PV_STAT(pv_entry_allocs++);
pv_entry_count++;
if (pv_entry_count > pv_entry_high_water)
if (ratecheck(&lastprint, &printinterval))
printf("Approaching the limit on PV entries, consider "
"increasing either the vm.pmap.shpgperproc or the "
"vm.pmap.pv_entry_max tunable.\n");
retry:
pc = TAILQ_FIRST(&pmap->pm_pvchunk);
if (pc != NULL) {
for (field = 0; field < _NPCM; field++) {
if (pc->pc_map[field]) {
bit = bsfl(pc->pc_map[field]);
break;
}
}
if (field < _NPCM) {
pv = &pc->pc_pventry[field * 32 + bit];
pc->pc_map[field] &= ~(1ul << bit);
/* If this was the last item, move it to tail */
for (field = 0; field < _NPCM; field++)
if (pc->pc_map[field] != 0) {
PV_STAT(pv_entry_spare--);
return (pv); /* not full, return */
}
TAILQ_REMOVE(&pmap->pm_pvchunk, pc, pc_list);
TAILQ_INSERT_TAIL(&pmap->pm_pvchunk, pc, pc_list);
PV_STAT(pv_entry_spare--);
return (pv);
}
}
/*
* Access to the ptelist "pv_vafree" is synchronized by the pvh
* global lock. If "pv_vafree" is currently non-empty, it will
* remain non-empty until pmap_ptelist_alloc() completes.
*/
if (pv_vafree == 0 || (m = vm_page_alloc(NULL, 0, VM_ALLOC_NORMAL |
VM_ALLOC_NOOBJ | VM_ALLOC_WIRED)) == NULL) {
if (try) {
pv_entry_count--;
PV_STAT(pc_chunk_tryfail++);
return (NULL);
}
m = pmap_pv_reclaim(pmap);
if (m == NULL)
goto retry;
}
PV_STAT(pc_chunk_count++);
PV_STAT(pc_chunk_allocs++);
pc = (struct pv_chunk *)pmap_ptelist_alloc(&pv_vafree);
pmap_qenter((vm_offset_t)pc, &m, 1);
pc->pc_pmap = pmap;
pc->pc_map[0] = pc_freemask[0] & ~1ul; /* preallocated bit 0 */
for (field = 1; field < _NPCM; field++)
pc->pc_map[field] = pc_freemask[field];
TAILQ_INSERT_TAIL(&pv_chunks, pc, pc_lru);
pv = &pc->pc_pventry[0];
TAILQ_INSERT_HEAD(&pmap->pm_pvchunk, pc, pc_list);
PV_STAT(pv_entry_spare += _NPCPV - 1);
return (pv);
}
static __inline pv_entry_t
pmap_pvh_remove(struct md_page *pvh, pmap_t pmap, vm_offset_t va)
{
pv_entry_t pv;
rw_assert(&pvh_global_lock, RA_WLOCKED);
TAILQ_FOREACH(pv, &pvh->pv_list, pv_list) {
if (pmap == PV_PMAP(pv) && va == pv->pv_va) {
TAILQ_REMOVE(&pvh->pv_list, pv, pv_list);
break;
}
}
return (pv);
}
static void
pmap_pv_demote_pde(pmap_t pmap, vm_offset_t va, vm_paddr_t pa)
{
struct md_page *pvh;
pv_entry_t pv;
vm_offset_t va_last;
vm_page_t m;
rw_assert(&pvh_global_lock, RA_WLOCKED);
KASSERT((pa & PDRMASK) == 0,
("pmap_pv_demote_pde: pa is not 4mpage aligned"));
/*
* Transfer the 4mpage's pv entry for this mapping to the first
* page's pv list.
*/
pvh = pa_to_pvh(pa);
va = trunc_4mpage(va);
pv = pmap_pvh_remove(pvh, pmap, va);
KASSERT(pv != NULL, ("pmap_pv_demote_pde: pv not found"));
m = PHYS_TO_VM_PAGE(pa);
TAILQ_INSERT_TAIL(&m->md.pv_list, pv, pv_list);
/* Instantiate the remaining NPTEPG - 1 pv entries. */
va_last = va + NBPDR - PAGE_SIZE;
do {
m++;
KASSERT((m->oflags & VPO_UNMANAGED) == 0,
("pmap_pv_demote_pde: page %p is not managed", m));
va += PAGE_SIZE;
pmap_insert_entry(pmap, va, m);
} while (va < va_last);
}
static void
pmap_pv_promote_pde(pmap_t pmap, vm_offset_t va, vm_paddr_t pa)
{
struct md_page *pvh;
pv_entry_t pv;
vm_offset_t va_last;
vm_page_t m;
rw_assert(&pvh_global_lock, RA_WLOCKED);
KASSERT((pa & PDRMASK) == 0,
("pmap_pv_promote_pde: pa is not 4mpage aligned"));
/*
* Transfer the first page's pv entry for this mapping to the
* 4mpage's pv list. Aside from avoiding the cost of a call
* to get_pv_entry(), a transfer avoids the possibility that
* get_pv_entry() calls pmap_collect() and that pmap_collect()
* removes one of the mappings that is being promoted.
*/
m = PHYS_TO_VM_PAGE(pa);
va = trunc_4mpage(va);
pv = pmap_pvh_remove(&m->md, pmap, va);
KASSERT(pv != NULL, ("pmap_pv_promote_pde: pv not found"));
pvh = pa_to_pvh(pa);
TAILQ_INSERT_TAIL(&pvh->pv_list, pv, pv_list);
/* Free the remaining NPTEPG - 1 pv entries. */
va_last = va + NBPDR - PAGE_SIZE;
do {
m++;
va += PAGE_SIZE;
pmap_pvh_free(&m->md, pmap, va);
} while (va < va_last);
}
static void
pmap_pvh_free(struct md_page *pvh, pmap_t pmap, vm_offset_t va)
{
pv_entry_t pv;
pv = pmap_pvh_remove(pvh, pmap, va);
KASSERT(pv != NULL, ("pmap_pvh_free: pv not found"));
free_pv_entry(pmap, pv);
}
static void
pmap_remove_entry(pmap_t pmap, vm_page_t m, vm_offset_t va)
{
struct md_page *pvh;
rw_assert(&pvh_global_lock, RA_WLOCKED);
pmap_pvh_free(&m->md, pmap, va);
if (TAILQ_EMPTY(&m->md.pv_list) && (m->flags & PG_FICTITIOUS) == 0) {
pvh = pa_to_pvh(VM_PAGE_TO_PHYS(m));
if (TAILQ_EMPTY(&pvh->pv_list))
vm_page_aflag_clear(m, PGA_WRITEABLE);
}
}
/*
* Create a pv entry for page at pa for
* (pmap, va).
*/
static void
pmap_insert_entry(pmap_t pmap, vm_offset_t va, vm_page_t m)
{
pv_entry_t pv;
rw_assert(&pvh_global_lock, RA_WLOCKED);
PMAP_LOCK_ASSERT(pmap, MA_OWNED);
pv = get_pv_entry(pmap, FALSE);
pv->pv_va = va;
TAILQ_INSERT_TAIL(&m->md.pv_list, pv, pv_list);
}
/*
* Conditionally create a pv entry.
*/
static boolean_t
pmap_try_insert_pv_entry(pmap_t pmap, vm_offset_t va, vm_page_t m)
{
pv_entry_t pv;
rw_assert(&pvh_global_lock, RA_WLOCKED);
PMAP_LOCK_ASSERT(pmap, MA_OWNED);
if (pv_entry_count < pv_entry_high_water &&
(pv = get_pv_entry(pmap, TRUE)) != NULL) {
pv->pv_va = va;
TAILQ_INSERT_TAIL(&m->md.pv_list, pv, pv_list);
return (TRUE);
} else
return (FALSE);
}
/*
* Create the pv entries for each of the pages within a superpage.
*/
static boolean_t
pmap_pv_insert_pde(pmap_t pmap, vm_offset_t va, vm_paddr_t pa)
{
struct md_page *pvh;
pv_entry_t pv;
rw_assert(&pvh_global_lock, RA_WLOCKED);
if (pv_entry_count < pv_entry_high_water &&
(pv = get_pv_entry(pmap, TRUE)) != NULL) {
pv->pv_va = va;
pvh = pa_to_pvh(pa);
TAILQ_INSERT_TAIL(&pvh->pv_list, pv, pv_list);
return (TRUE);
} else
return (FALSE);
}
/*
* Fills a page table page with mappings to consecutive physical pages.
*/
static void
pmap_fill_ptp(pt_entry_t *firstpte, pt_entry_t newpte)
{
pt_entry_t *pte;
for (pte = firstpte; pte < firstpte + NPTEPG; pte++) {
*pte = newpte;
newpte += PAGE_SIZE;
}
}
/*
* Tries to demote a 2- or 4MB page mapping. If demotion fails, the
* 2- or 4MB page mapping is invalidated.
*/
static boolean_t
pmap_demote_pde(pmap_t pmap, pd_entry_t *pde, vm_offset_t va)
{
pd_entry_t newpde, oldpde;
pt_entry_t *firstpte, newpte;
vm_paddr_t mptepa;
vm_page_t free, mpte;
PMAP_LOCK_ASSERT(pmap, MA_OWNED);
oldpde = *pde;
KASSERT((oldpde & (PG_PS | PG_V)) == (PG_PS | PG_V),
("pmap_demote_pde: oldpde is missing PG_PS and/or PG_V"));
mpte = pmap_lookup_pt_page(pmap, va);
if (mpte != NULL)
pmap_remove_pt_page(pmap, mpte);
else {
KASSERT((oldpde & PG_W) == 0,
("pmap_demote_pde: page table page for a wired mapping"
" is missing"));
/*
* Invalidate the 2- or 4MB page mapping and return
* "failure" if the mapping was never accessed or the
* allocation of the new page table page fails.
*/
if ((oldpde & PG_A) == 0 || (mpte = vm_page_alloc(NULL,
va >> PDRSHIFT, VM_ALLOC_NOOBJ | VM_ALLOC_NORMAL |
VM_ALLOC_WIRED)) == NULL) {
free = NULL;
pmap_remove_pde(pmap, pde, trunc_4mpage(va), &free);
pmap_invalidate_page(pmap, trunc_4mpage(va));
pmap_free_zero_pages(free);
CTR2(KTR_PMAP, "pmap_demote_pde: failure for va %#x"
" in pmap %p", va, pmap);
return (FALSE);
}
if (va < VM_MAXUSER_ADDRESS)
pmap->pm_stats.resident_count++;
}
mptepa = VM_PAGE_TO_PHYS(mpte);
/*
* If the page mapping is in the kernel's address space, then the
* KPTmap can provide access to the page table page. Otherwise,
* temporarily map the page table page (mpte) into the kernel's
* address space at either PADDR1 or PADDR2.
*/
if (va >= KERNBASE)
firstpte = &KPTmap[i386_btop(trunc_4mpage(va))];
else if (curthread->td_pinned > 0 && rw_wowned(&pvh_global_lock)) {
if ((*PMAP1 & PG_FRAME) != mptepa) {
*PMAP1 = mptepa | PG_RW | PG_V | PG_A | PG_M;
#ifdef SMP
PMAP1cpu = PCPU_GET(cpuid);
#endif
invlcaddr(PADDR1);
PMAP1changed++;
} else
#ifdef SMP
if (PMAP1cpu != PCPU_GET(cpuid)) {
PMAP1cpu = PCPU_GET(cpuid);
invlcaddr(PADDR1);
PMAP1changedcpu++;
} else
#endif
PMAP1unchanged++;
firstpte = PADDR1;
} else {
mtx_lock(&PMAP2mutex);
if ((*PMAP2 & PG_FRAME) != mptepa) {
*PMAP2 = mptepa | PG_RW | PG_V | PG_A | PG_M;
pmap_invalidate_page(kernel_pmap, (vm_offset_t)PADDR2);
}
firstpte = PADDR2;
}
newpde = mptepa | PG_M | PG_A | (oldpde & PG_U) | PG_RW | PG_V;
KASSERT((oldpde & PG_A) != 0,
("pmap_demote_pde: oldpde is missing PG_A"));
KASSERT((oldpde & (PG_M | PG_RW)) != PG_RW,
("pmap_demote_pde: oldpde is missing PG_M"));
newpte = oldpde & ~PG_PS;
if ((newpte & PG_PDE_PAT) != 0)
newpte ^= PG_PDE_PAT | PG_PTE_PAT;
/*
* If the page table page is new, initialize it.
*/
if (mpte->wire_count == 1) {
mpte->wire_count = NPTEPG;
pmap_fill_ptp(firstpte, newpte);
}
KASSERT((*firstpte & PG_FRAME) == (newpte & PG_FRAME),
("pmap_demote_pde: firstpte and newpte map different physical"
" addresses"));
/*
* If the mapping has changed attributes, update the page table
* entries.
*/
if ((*firstpte & PG_PTE_PROMOTE) != (newpte & PG_PTE_PROMOTE))
pmap_fill_ptp(firstpte, newpte);
/*
* Demote the mapping. This pmap is locked. The old PDE has
* PG_A set. If the old PDE has PG_RW set, it also has PG_M
* set. Thus, there is no danger of a race with another
* processor changing the setting of PG_A and/or PG_M between
* the read above and the store below.
*/
if (workaround_erratum383)
pmap_update_pde(pmap, va, pde, newpde);
else if (pmap == kernel_pmap)
pmap_kenter_pde(va, newpde);
else
pde_store(pde, newpde);
if (firstpte == PADDR2)
mtx_unlock(&PMAP2mutex);
/*
* Invalidate the recursive mapping of the page table page.
*/
pmap_invalidate_page(pmap, (vm_offset_t)vtopte(va));
/*
* Demote the pv entry. This depends on the earlier demotion
* of the mapping. Specifically, the (re)creation of a per-
* page pv entry might trigger the execution of pmap_collect(),
* which might reclaim a newly (re)created per-page pv entry
* and destroy the associated mapping. In order to destroy
* the mapping, the PDE must have already changed from mapping
* the 2mpage to referencing the page table page.
*/
if ((oldpde & PG_MANAGED) != 0)
pmap_pv_demote_pde(pmap, va, oldpde & PG_PS_FRAME);
pmap_pde_demotions++;
CTR2(KTR_PMAP, "pmap_demote_pde: success for va %#x"
" in pmap %p", va, pmap);
return (TRUE);
}
/*
* pmap_remove_pde: do the things to unmap a superpage in a process
*/
static void
pmap_remove_pde(pmap_t pmap, pd_entry_t *pdq, vm_offset_t sva,
vm_page_t *free)
{
struct md_page *pvh;
pd_entry_t oldpde;
vm_offset_t eva, va;
vm_page_t m, mpte;
PMAP_LOCK_ASSERT(pmap, MA_OWNED);
KASSERT((sva & PDRMASK) == 0,
("pmap_remove_pde: sva is not 4mpage aligned"));
oldpde = pte_load_clear(pdq);
if (oldpde & PG_W)
pmap->pm_stats.wired_count -= NBPDR / PAGE_SIZE;
/*
* Machines that don't support invlpg, also don't support
* PG_G.
*/
if (oldpde & PG_G)
pmap_invalidate_page(kernel_pmap, sva);
pmap->pm_stats.resident_count -= NBPDR / PAGE_SIZE;
if (oldpde & PG_MANAGED) {
pvh = pa_to_pvh(oldpde & PG_PS_FRAME);
pmap_pvh_free(pvh, pmap, sva);
eva = sva + NBPDR;
for (va = sva, m = PHYS_TO_VM_PAGE(oldpde & PG_PS_FRAME);
va < eva; va += PAGE_SIZE, m++) {
if ((oldpde & (PG_M | PG_RW)) == (PG_M | PG_RW))
vm_page_dirty(m);
if (oldpde & PG_A)
vm_page_aflag_set(m, PGA_REFERENCED);
if (TAILQ_EMPTY(&m->md.pv_list) &&
TAILQ_EMPTY(&pvh->pv_list))
vm_page_aflag_clear(m, PGA_WRITEABLE);
}
}
if (pmap == kernel_pmap) {
if (!pmap_demote_pde(pmap, pdq, sva))
panic("pmap_remove_pde: failed demotion");
} else {
mpte = pmap_lookup_pt_page(pmap, sva);
if (mpte != NULL) {
pmap_remove_pt_page(pmap, mpte);
pmap->pm_stats.resident_count--;
KASSERT(mpte->wire_count == NPTEPG,
("pmap_remove_pde: pte page wire count error"));
mpte->wire_count = 0;
pmap_add_delayed_free_list(mpte, free, FALSE);
atomic_subtract_int(&cnt.v_wire_count, 1);
}
}
}
/*
* pmap_remove_pte: do the things to unmap a page in a process
*/
static int
pmap_remove_pte(pmap_t pmap, pt_entry_t *ptq, vm_offset_t va, vm_page_t *free)
{
pt_entry_t oldpte;
vm_page_t m;
rw_assert(&pvh_global_lock, RA_WLOCKED);
PMAP_LOCK_ASSERT(pmap, MA_OWNED);
oldpte = pte_load_clear(ptq);
if (oldpte & PG_W)
pmap->pm_stats.wired_count -= 1;
/*
* Machines that don't support invlpg, also don't support
* PG_G.
*/
if (oldpte & PG_G)
pmap_invalidate_page(kernel_pmap, va);
pmap->pm_stats.resident_count -= 1;
if (oldpte & PG_MANAGED) {
m = PHYS_TO_VM_PAGE(oldpte & PG_FRAME);
if ((oldpte & (PG_M | PG_RW)) == (PG_M | PG_RW))
vm_page_dirty(m);
if (oldpte & PG_A)
vm_page_aflag_set(m, PGA_REFERENCED);
pmap_remove_entry(pmap, m, va);
}
return (pmap_unuse_pt(pmap, va, free));
}
/*
* Remove a single page from a process address space
*/
static void
pmap_remove_page(pmap_t pmap, vm_offset_t va, vm_page_t *free)
{
pt_entry_t *pte;
rw_assert(&pvh_global_lock, RA_WLOCKED);
KASSERT(curthread->td_pinned > 0, ("curthread not pinned"));
PMAP_LOCK_ASSERT(pmap, MA_OWNED);
if ((pte = pmap_pte_quick(pmap, va)) == NULL || *pte == 0)
return;
pmap_remove_pte(pmap, pte, va, free);
pmap_invalidate_page(pmap, va);
}
/*
* Remove the given range of addresses from the specified map.
*
* It is assumed that the start and end are properly
* rounded to the page size.
*/
void
pmap_remove(pmap_t pmap, vm_offset_t sva, vm_offset_t eva)
{
vm_offset_t pdnxt;
pd_entry_t ptpaddr;
pt_entry_t *pte;
vm_page_t free = NULL;
int anyvalid;
/*
* Perform an unsynchronized read. This is, however, safe.
*/
if (pmap->pm_stats.resident_count == 0)
return;
anyvalid = 0;
rw_wlock(&pvh_global_lock);
sched_pin();
PMAP_LOCK(pmap);
/*
* special handling of removing one page. a very
* common operation and easy to short circuit some
* code.
*/
if ((sva + PAGE_SIZE == eva) &&
((pmap->pm_pdir[(sva >> PDRSHIFT)] & PG_PS) == 0)) {
pmap_remove_page(pmap, sva, &free);
goto out;
}
for (; sva < eva; sva = pdnxt) {
u_int pdirindex;
/*
* Calculate index for next page table.
*/
pdnxt = (sva + NBPDR) & ~PDRMASK;
if (pdnxt < sva)
pdnxt = eva;
if (pmap->pm_stats.resident_count == 0)
break;
pdirindex = sva >> PDRSHIFT;
ptpaddr = pmap->pm_pdir[pdirindex];
/*
* Weed out invalid mappings. Note: we assume that the page
* directory table is always allocated, and in kernel virtual.
*/
if (ptpaddr == 0)
continue;
/*
* Check for large page.
*/
if ((ptpaddr & PG_PS) != 0) {
/*
* Are we removing the entire large page? If not,
* demote the mapping and fall through.
*/
if (sva + NBPDR == pdnxt && eva >= pdnxt) {
/*
* The TLB entry for a PG_G mapping is
* invalidated by pmap_remove_pde().
*/
if ((ptpaddr & PG_G) == 0)
anyvalid = 1;
pmap_remove_pde(pmap,
&pmap->pm_pdir[pdirindex], sva, &free);
continue;
} else if (!pmap_demote_pde(pmap,
&pmap->pm_pdir[pdirindex], sva)) {
/* The large page mapping was destroyed. */
continue;
}
}
/*
* Limit our scan to either the end of the va represented
* by the current page table page, or to the end of the
* range being removed.
*/
if (pdnxt > eva)
pdnxt = eva;
for (pte = pmap_pte_quick(pmap, sva); sva != pdnxt; pte++,
sva += PAGE_SIZE) {
if (*pte == 0)
continue;
/*
* The TLB entry for a PG_G mapping is invalidated
* by pmap_remove_pte().
*/
if ((*pte & PG_G) == 0)
anyvalid = 1;
if (pmap_remove_pte(pmap, pte, sva, &free))
break;
}
}
out:
sched_unpin();
if (anyvalid)
pmap_invalidate_all(pmap);
rw_wunlock(&pvh_global_lock);
PMAP_UNLOCK(pmap);
pmap_free_zero_pages(free);
}
/*
* Routine: pmap_remove_all
* Function:
* Removes this physical page from
* all physical maps in which it resides.
* Reflects back modify bits to the pager.
*
* Notes:
* Original versions of this routine were very
* inefficient because they iteratively called
* pmap_remove (slow...)
*/
void
pmap_remove_all(vm_page_t m)
{
struct md_page *pvh;
pv_entry_t pv;
pmap_t pmap;
pt_entry_t *pte, tpte;
pd_entry_t *pde;
vm_offset_t va;
vm_page_t free;
KASSERT((m->oflags & VPO_UNMANAGED) == 0,
("pmap_remove_all: page %p is not managed", m));
free = NULL;
rw_wlock(&pvh_global_lock);
sched_pin();
if ((m->flags & PG_FICTITIOUS) != 0)
goto small_mappings;
pvh = pa_to_pvh(VM_PAGE_TO_PHYS(m));
while ((pv = TAILQ_FIRST(&pvh->pv_list)) != NULL) {
va = pv->pv_va;
pmap = PV_PMAP(pv);
PMAP_LOCK(pmap);
pde = pmap_pde(pmap, va);
(void)pmap_demote_pde(pmap, pde, va);
PMAP_UNLOCK(pmap);
}
small_mappings:
while ((pv = TAILQ_FIRST(&m->md.pv_list)) != NULL) {
pmap = PV_PMAP(pv);
PMAP_LOCK(pmap);
pmap->pm_stats.resident_count--;
pde = pmap_pde(pmap, pv->pv_va);
KASSERT((*pde & PG_PS) == 0, ("pmap_remove_all: found"
" a 4mpage in page %p's pv list", m));
pte = pmap_pte_quick(pmap, pv->pv_va);
tpte = pte_load_clear(pte);
if (tpte & PG_W)
pmap->pm_stats.wired_count--;
if (tpte & PG_A)
vm_page_aflag_set(m, PGA_REFERENCED);
/*
* Update the vm_page_t clean and reference bits.
*/
if ((tpte & (PG_M | PG_RW)) == (PG_M | PG_RW))
vm_page_dirty(m);
pmap_unuse_pt(pmap, pv->pv_va, &free);
pmap_invalidate_page(pmap, pv->pv_va);
TAILQ_REMOVE(&m->md.pv_list, pv, pv_list);
free_pv_entry(pmap, pv);
PMAP_UNLOCK(pmap);
}
vm_page_aflag_clear(m, PGA_WRITEABLE);
sched_unpin();
rw_wunlock(&pvh_global_lock);
pmap_free_zero_pages(free);
}
/*
* pmap_protect_pde: do the things to protect a 4mpage in a process
*/
static boolean_t
pmap_protect_pde(pmap_t pmap, pd_entry_t *pde, vm_offset_t sva, vm_prot_t prot)
{
pd_entry_t newpde, oldpde;
vm_offset_t eva, va;
vm_page_t m;
boolean_t anychanged;
PMAP_LOCK_ASSERT(pmap, MA_OWNED);
KASSERT((sva & PDRMASK) == 0,
("pmap_protect_pde: sva is not 4mpage aligned"));
anychanged = FALSE;
retry:
oldpde = newpde = *pde;
if (oldpde & PG_MANAGED) {
eva = sva + NBPDR;
for (va = sva, m = PHYS_TO_VM_PAGE(oldpde & PG_PS_FRAME);
va < eva; va += PAGE_SIZE, m++)
if ((oldpde & (PG_M | PG_RW)) == (PG_M | PG_RW))
vm_page_dirty(m);
}
if ((prot & VM_PROT_WRITE) == 0)
newpde &= ~(PG_RW | PG_M);
#ifdef PAE
if ((prot & VM_PROT_EXECUTE) == 0)
newpde |= pg_nx;
#endif
if (newpde != oldpde) {
if (!pde_cmpset(pde, oldpde, newpde))
goto retry;
if (oldpde & PG_G)
pmap_invalidate_page(pmap, sva);
else
anychanged = TRUE;
}
return (anychanged);
}
/*
* Set the physical protection on the
* specified range of this map as requested.
*/
void
pmap_protect(pmap_t pmap, vm_offset_t sva, vm_offset_t eva, vm_prot_t prot)
{
vm_offset_t pdnxt;
pd_entry_t ptpaddr;
pt_entry_t *pte;
boolean_t anychanged, pv_lists_locked;
if ((prot & VM_PROT_READ) == VM_PROT_NONE) {
pmap_remove(pmap, sva, eva);
return;
}
#ifdef PAE
if ((prot & (VM_PROT_WRITE|VM_PROT_EXECUTE)) ==
(VM_PROT_WRITE|VM_PROT_EXECUTE))
return;
#else
if (prot & VM_PROT_WRITE)
return;
#endif
if (pmap_is_current(pmap))
pv_lists_locked = FALSE;
else {
pv_lists_locked = TRUE;
resume:
rw_wlock(&pvh_global_lock);
sched_pin();
}
anychanged = FALSE;
PMAP_LOCK(pmap);
for (; sva < eva; sva = pdnxt) {
pt_entry_t obits, pbits;
u_int pdirindex;
pdnxt = (sva + NBPDR) & ~PDRMASK;
if (pdnxt < sva)
pdnxt = eva;
pdirindex = sva >> PDRSHIFT;
ptpaddr = pmap->pm_pdir[pdirindex];
/*
* Weed out invalid mappings. Note: we assume that the page
* directory table is always allocated, and in kernel virtual.
*/
if (ptpaddr == 0)
continue;
/*
* Check for large page.
*/
if ((ptpaddr & PG_PS) != 0) {
/*
* Are we protecting the entire large page? If not,
* demote the mapping and fall through.
*/
if (sva + NBPDR == pdnxt && eva >= pdnxt) {
/*
* The TLB entry for a PG_G mapping is
* invalidated by pmap_protect_pde().
*/
if (pmap_protect_pde(pmap,
&pmap->pm_pdir[pdirindex], sva, prot))
anychanged = TRUE;
continue;
} else {
if (!pv_lists_locked) {
pv_lists_locked = TRUE;
if (!rw_try_wlock(&pvh_global_lock)) {
if (anychanged)
pmap_invalidate_all(
pmap);
PMAP_UNLOCK(pmap);
goto resume;
}
}
if (!pmap_demote_pde(pmap,
&pmap->pm_pdir[pdirindex], sva)) {
/*
* The large page mapping was
* destroyed.
*/
continue;
}
}
}
if (pdnxt > eva)
pdnxt = eva;
for (pte = pmap_pte_quick(pmap, sva); sva != pdnxt; pte++,
sva += PAGE_SIZE) {
vm_page_t m;
retry:
/*
* Regardless of whether a pte is 32 or 64 bits in
* size, PG_RW, PG_A, and PG_M are among the least
* significant 32 bits.
*/
obits = pbits = *pte;
if ((pbits & PG_V) == 0)
continue;
if ((prot & VM_PROT_WRITE) == 0) {
if ((pbits & (PG_MANAGED | PG_M | PG_RW)) ==
(PG_MANAGED | PG_M | PG_RW)) {
m = PHYS_TO_VM_PAGE(pbits & PG_FRAME);
vm_page_dirty(m);
}
pbits &= ~(PG_RW | PG_M);
}
#ifdef PAE
if ((prot & VM_PROT_EXECUTE) == 0)
pbits |= pg_nx;
#endif
if (pbits != obits) {
#ifdef PAE
if (!atomic_cmpset_64(pte, obits, pbits))
goto retry;
#else
if (!atomic_cmpset_int((u_int *)pte, obits,
pbits))
goto retry;
#endif
if (obits & PG_G)
pmap_invalidate_page(pmap, sva);
else
anychanged = TRUE;
}
}
}
if (anychanged)
pmap_invalidate_all(pmap);
if (pv_lists_locked) {
sched_unpin();
rw_wunlock(&pvh_global_lock);
}
PMAP_UNLOCK(pmap);
}
/*
* Tries to promote the 512 or 1024, contiguous 4KB page mappings that are
* within a single page table page (PTP) to a single 2- or 4MB page mapping.
* For promotion to occur, two conditions must be met: (1) the 4KB page
* mappings must map aligned, contiguous physical memory and (2) the 4KB page
* mappings must have identical characteristics.
*
* Managed (PG_MANAGED) mappings within the kernel address space are not
* promoted. The reason is that kernel PDEs are replicated in each pmap but
* pmap_clear_ptes() and pmap_ts_referenced() only read the PDE from the kernel
* pmap.
*/
static void
pmap_promote_pde(pmap_t pmap, pd_entry_t *pde, vm_offset_t va)
{
pd_entry_t newpde;
pt_entry_t *firstpte, oldpte, pa, *pte;
vm_offset_t oldpteva;
vm_page_t mpte;
PMAP_LOCK_ASSERT(pmap, MA_OWNED);
/*
* Examine the first PTE in the specified PTP. Abort if this PTE is
* either invalid, unused, or does not map the first 4KB physical page
* within a 2- or 4MB page.
*/
firstpte = pmap_pte_quick(pmap, trunc_4mpage(va));
setpde:
newpde = *firstpte;
if ((newpde & ((PG_FRAME & PDRMASK) | PG_A | PG_V)) != (PG_A | PG_V)) {
pmap_pde_p_failures++;
CTR2(KTR_PMAP, "pmap_promote_pde: failure for va %#x"
" in pmap %p", va, pmap);
return;
}
if ((*firstpte & PG_MANAGED) != 0 && pmap == kernel_pmap) {
pmap_pde_p_failures++;
CTR2(KTR_PMAP, "pmap_promote_pde: failure for va %#x"
" in pmap %p", va, pmap);
return;
}
if ((newpde & (PG_M | PG_RW)) == PG_RW) {
/*
* When PG_M is already clear, PG_RW can be cleared without
* a TLB invalidation.
*/
if (!atomic_cmpset_int((u_int *)firstpte, newpde, newpde &
~PG_RW))
goto setpde;
newpde &= ~PG_RW;
}
/*
* Examine each of the other PTEs in the specified PTP. Abort if this
* PTE maps an unexpected 4KB physical page or does not have identical
* characteristics to the first PTE.
*/
pa = (newpde & (PG_PS_FRAME | PG_A | PG_V)) + NBPDR - PAGE_SIZE;
for (pte = firstpte + NPTEPG - 1; pte > firstpte; pte--) {
setpte:
oldpte = *pte;
if ((oldpte & (PG_FRAME | PG_A | PG_V)) != pa) {
pmap_pde_p_failures++;
CTR2(KTR_PMAP, "pmap_promote_pde: failure for va %#x"
" in pmap %p", va, pmap);
return;
}
if ((oldpte & (PG_M | PG_RW)) == PG_RW) {
/*
* When PG_M is already clear, PG_RW can be cleared
* without a TLB invalidation.
*/
if (!atomic_cmpset_int((u_int *)pte, oldpte,
oldpte & ~PG_RW))
goto setpte;
oldpte &= ~PG_RW;
oldpteva = (oldpte & PG_FRAME & PDRMASK) |
(va & ~PDRMASK);
CTR2(KTR_PMAP, "pmap_promote_pde: protect for va %#x"
" in pmap %p", oldpteva, pmap);
}
if ((oldpte & PG_PTE_PROMOTE) != (newpde & PG_PTE_PROMOTE)) {
pmap_pde_p_failures++;
CTR2(KTR_PMAP, "pmap_promote_pde: failure for va %#x"
" in pmap %p", va, pmap);
return;
}
pa -= PAGE_SIZE;
}
/*
* Save the page table page in its current state until the PDE
* mapping the superpage is demoted by pmap_demote_pde() or
* destroyed by pmap_remove_pde().
*/
mpte = PHYS_TO_VM_PAGE(*pde & PG_FRAME);
KASSERT(mpte >= vm_page_array &&
mpte < &vm_page_array[vm_page_array_size],
("pmap_promote_pde: page table page is out of range"));
KASSERT(mpte->pindex == va >> PDRSHIFT,
("pmap_promote_pde: page table page's pindex is wrong"));
pmap_insert_pt_page(pmap, mpte);
/*
* Promote the pv entries.
*/
if ((newpde & PG_MANAGED) != 0)
pmap_pv_promote_pde(pmap, va, newpde & PG_PS_FRAME);
/*
* Propagate the PAT index to its proper position.
*/
if ((newpde & PG_PTE_PAT) != 0)
newpde ^= PG_PDE_PAT | PG_PTE_PAT;
/*
* Map the superpage.
*/
if (workaround_erratum383)
pmap_update_pde(pmap, va, pde, PG_PS | newpde);
else if (pmap == kernel_pmap)
pmap_kenter_pde(va, PG_PS | newpde);
else
pde_store(pde, PG_PS | newpde);
pmap_pde_promotions++;
CTR2(KTR_PMAP, "pmap_promote_pde: success for va %#x"
" in pmap %p", va, pmap);
}
/*
* Insert the given physical page (p) at
* the specified virtual address (v) in the
* target physical map with the protection requested.
*
* If specified, the page will be wired down, meaning
* that the related pte can not be reclaimed.
*
* NB: This is the only routine which MAY NOT lazy-evaluate
* or lose information. That is, this routine must actually
* insert this page into the given map NOW.
*/
void
pmap_enter(pmap_t pmap, vm_offset_t va, vm_prot_t access, vm_page_t m,
vm_prot_t prot, boolean_t wired)
{
pd_entry_t *pde;
pt_entry_t *pte;
pt_entry_t newpte, origpte;
pv_entry_t pv;
vm_paddr_t opa, pa;
vm_page_t mpte, om;
boolean_t invlva;
va = trunc_page(va);
KASSERT(va <= VM_MAX_KERNEL_ADDRESS, ("pmap_enter: toobig"));
KASSERT(va < UPT_MIN_ADDRESS || va >= UPT_MAX_ADDRESS,
("pmap_enter: invalid to pmap_enter page table pages (va: 0x%x)",
va));
KASSERT((m->oflags & (VPO_UNMANAGED | VPO_BUSY)) != 0 ||
VM_OBJECT_LOCKED(m->object),
("pmap_enter: page %p is not busy", m));
mpte = NULL;
rw_wlock(&pvh_global_lock);
PMAP_LOCK(pmap);
sched_pin();
/*
* In the case that a page table page is not
* resident, we are creating it here.
*/
if (va < VM_MAXUSER_ADDRESS) {
mpte = pmap_allocpte(pmap, va, M_WAITOK);
}
pde = pmap_pde(pmap, va);
if ((*pde & PG_PS) != 0)
panic("pmap_enter: attempted pmap_enter on 4MB page");
pte = pmap_pte_quick(pmap, va);
/*
* Page Directory table entry not valid, we need a new PT page
*/
if (pte == NULL) {
panic("pmap_enter: invalid page directory pdir=%#jx, va=%#x",
(uintmax_t)pmap->pm_pdir[PTDPTDI], va);
}
pa = VM_PAGE_TO_PHYS(m);
om = NULL;
origpte = *pte;
opa = origpte & PG_FRAME;
/*
* Mapping has not changed, must be protection or wiring change.
*/
if (origpte && (opa == pa)) {
/*
* Wiring change, just update stats. We don't worry about
* wiring PT pages as they remain resident as long as there
* are valid mappings in them. Hence, if a user page is wired,
* the PT page will be also.
*/
if (wired && ((origpte & PG_W) == 0))
pmap->pm_stats.wired_count++;
else if (!wired && (origpte & PG_W))
pmap->pm_stats.wired_count--;
/*
* Remove extra pte reference
*/
if (mpte)
mpte->wire_count--;
if (origpte & PG_MANAGED) {
om = m;
pa |= PG_MANAGED;
}
goto validate;
}
pv = NULL;
/*
* Mapping has changed, invalidate old range and fall through to
* handle validating new mapping.
*/
if (opa) {
if (origpte & PG_W)
pmap->pm_stats.wired_count--;
if (origpte & PG_MANAGED) {
om = PHYS_TO_VM_PAGE(opa);
pv = pmap_pvh_remove(&om->md, pmap, va);
}
if (mpte != NULL) {
mpte->wire_count--;
KASSERT(mpte->wire_count > 0,
("pmap_enter: missing reference to page table page,"
" va: 0x%x", va));
}
} else
pmap->pm_stats.resident_count++;
/*
* Enter on the PV list if part of our managed memory.
*/
if ((m->oflags & VPO_UNMANAGED) == 0) {
KASSERT(va < kmi.clean_sva || va >= kmi.clean_eva,
("pmap_enter: managed mapping within the clean submap"));
if (pv == NULL)
pv = get_pv_entry(pmap, FALSE);
pv->pv_va = va;
TAILQ_INSERT_TAIL(&m->md.pv_list, pv, pv_list);
pa |= PG_MANAGED;
} else if (pv != NULL)
free_pv_entry(pmap, pv);
/*
* Increment counters
*/
if (wired)
pmap->pm_stats.wired_count++;
validate:
/*
* Now validate mapping with desired protection/wiring.
*/
newpte = (pt_entry_t)(pa | pmap_cache_bits(m->md.pat_mode, 0) | PG_V);
if ((prot & VM_PROT_WRITE) != 0) {
newpte |= PG_RW;
if ((newpte & PG_MANAGED) != 0)
vm_page_aflag_set(m, PGA_WRITEABLE);
}
#ifdef PAE
if ((prot & VM_PROT_EXECUTE) == 0)
newpte |= pg_nx;
#endif
if (wired)
newpte |= PG_W;
if (va < VM_MAXUSER_ADDRESS)
newpte |= PG_U;
if (pmap == kernel_pmap)
newpte |= pgeflag;
/*
* if the mapping or permission bits are different, we need
* to update the pte.
*/
if ((origpte & ~(PG_M|PG_A)) != newpte) {
newpte |= PG_A;
if ((access & VM_PROT_WRITE) != 0)
newpte |= PG_M;
if (origpte & PG_V) {
invlva = FALSE;
origpte = pte_load_store(pte, newpte);
if (origpte & PG_A) {
if (origpte & PG_MANAGED)
vm_page_aflag_set(om, PGA_REFERENCED);
if (opa != VM_PAGE_TO_PHYS(m))
invlva = TRUE;
#ifdef PAE
if ((origpte & PG_NX) == 0 &&
(newpte & PG_NX) != 0)
invlva = TRUE;
#endif
}
if ((origpte & (PG_M | PG_RW)) == (PG_M | PG_RW)) {
if ((origpte & PG_MANAGED) != 0)
vm_page_dirty(om);
if ((prot & VM_PROT_WRITE) == 0)
invlva = TRUE;
}
if ((origpte & PG_MANAGED) != 0 &&
TAILQ_EMPTY(&om->md.pv_list) &&
((om->flags & PG_FICTITIOUS) != 0 ||
TAILQ_EMPTY(&pa_to_pvh(opa)->pv_list)))
vm_page_aflag_clear(om, PGA_WRITEABLE);
if (invlva)
pmap_invalidate_page(pmap, va);
} else
pte_store(pte, newpte);
}
/*
* If both the page table page and the reservation are fully
* populated, then attempt promotion.
*/
if ((mpte == NULL || mpte->wire_count == NPTEPG) &&
pg_ps_enabled && (m->flags & PG_FICTITIOUS) == 0 &&
vm_reserv_level_iffullpop(m) == 0)
pmap_promote_pde(pmap, pde, va);
sched_unpin();
rw_wunlock(&pvh_global_lock);
PMAP_UNLOCK(pmap);
}
/*
* Tries to create a 2- or 4MB page mapping. Returns TRUE if successful and
* FALSE otherwise. Fails if (1) a page table page cannot be allocated without
* blocking, (2) a mapping already exists at the specified virtual address, or
* (3) a pv entry cannot be allocated without reclaiming another pv entry.
*/
static boolean_t
pmap_enter_pde(pmap_t pmap, vm_offset_t va, vm_page_t m, vm_prot_t prot)
{
pd_entry_t *pde, newpde;
rw_assert(&pvh_global_lock, RA_WLOCKED);
PMAP_LOCK_ASSERT(pmap, MA_OWNED);
pde = pmap_pde(pmap, va);
if (*pde != 0) {
CTR2(KTR_PMAP, "pmap_enter_pde: failure for va %#lx"
" in pmap %p", va, pmap);
return (FALSE);
}
newpde = VM_PAGE_TO_PHYS(m) | pmap_cache_bits(m->md.pat_mode, 1) |
PG_PS | PG_V;
if ((m->oflags & VPO_UNMANAGED) == 0) {
newpde |= PG_MANAGED;
/*
* Abort this mapping if its PV entry could not be created.
*/
if (!pmap_pv_insert_pde(pmap, va, VM_PAGE_TO_PHYS(m))) {
CTR2(KTR_PMAP, "pmap_enter_pde: failure for va %#lx"
" in pmap %p", va, pmap);
return (FALSE);
}
}
#ifdef PAE
if ((prot & VM_PROT_EXECUTE) == 0)
newpde |= pg_nx;
#endif
if (va < VM_MAXUSER_ADDRESS)
newpde |= PG_U;
/*
* Increment counters.
*/
pmap->pm_stats.resident_count += NBPDR / PAGE_SIZE;
/*
* Map the superpage.
*/
pde_store(pde, newpde);
pmap_pde_mappings++;
CTR2(KTR_PMAP, "pmap_enter_pde: success for va %#lx"
" in pmap %p", va, pmap);
return (TRUE);
}
/*
* Maps a sequence of resident pages belonging to the same object.
* The sequence begins with the given page m_start. This page is
* mapped at the given virtual address start. Each subsequent page is
* mapped at a virtual address that is offset from start by the same
* amount as the page is offset from m_start within the object. The
* last page in the sequence is the page with the largest offset from
* m_start that can be mapped at a virtual address less than the given
* virtual address end. Not every virtual page between start and end
* is mapped; only those for which a resident page exists with the
* corresponding offset from m_start are mapped.
*/
void
pmap_enter_object(pmap_t pmap, vm_offset_t start, vm_offset_t end,
vm_page_t m_start, vm_prot_t prot)
{
vm_offset_t va;
vm_page_t m, mpte;
vm_pindex_t diff, psize;
VM_OBJECT_LOCK_ASSERT(m_start->object, MA_OWNED);
psize = atop(end - start);
mpte = NULL;
m = m_start;
rw_wlock(&pvh_global_lock);
PMAP_LOCK(pmap);
while (m != NULL && (diff = m->pindex - m_start->pindex) < psize) {
va = start + ptoa(diff);
if ((va & PDRMASK) == 0 && va + NBPDR <= end &&
(VM_PAGE_TO_PHYS(m) & PDRMASK) == 0 &&
pg_ps_enabled && vm_reserv_level_iffullpop(m) == 0 &&
pmap_enter_pde(pmap, va, m, prot))
m = &m[NBPDR / PAGE_SIZE - 1];
else
mpte = pmap_enter_quick_locked(pmap, va, m, prot,
mpte);
m = TAILQ_NEXT(m, listq);
}
rw_wunlock(&pvh_global_lock);
PMAP_UNLOCK(pmap);
}
/*
* this code makes some *MAJOR* assumptions:
* 1. Current pmap & pmap exists.
* 2. Not wired.
* 3. Read access.
* 4. No page table pages.
* but is *MUCH* faster than pmap_enter...
*/
void
pmap_enter_quick(pmap_t pmap, vm_offset_t va, vm_page_t m, vm_prot_t prot)
{
rw_wlock(&pvh_global_lock);
PMAP_LOCK(pmap);
(void)pmap_enter_quick_locked(pmap, va, m, prot, NULL);
rw_wunlock(&pvh_global_lock);
PMAP_UNLOCK(pmap);
}
static vm_page_t
pmap_enter_quick_locked(pmap_t pmap, vm_offset_t va, vm_page_t m,
vm_prot_t prot, vm_page_t mpte)
{
pt_entry_t *pte;
vm_paddr_t pa;
vm_page_t free;
KASSERT(va < kmi.clean_sva || va >= kmi.clean_eva ||
(m->oflags & VPO_UNMANAGED) != 0,
("pmap_enter_quick_locked: managed mapping within the clean submap"));
rw_assert(&pvh_global_lock, RA_WLOCKED);
PMAP_LOCK_ASSERT(pmap, MA_OWNED);
/*
* In the case that a page table page is not
* resident, we are creating it here.
*/
if (va < VM_MAXUSER_ADDRESS) {
u_int ptepindex;
pd_entry_t ptepa;
/*
* Calculate pagetable page index
*/
ptepindex = va >> PDRSHIFT;
if (mpte && (mpte->pindex == ptepindex)) {
mpte->wire_count++;
} else {
/*
* Get the page directory entry
*/
ptepa = pmap->pm_pdir[ptepindex];
/*
* If the page table page is mapped, we just increment
* the hold count, and activate it.
*/
if (ptepa) {
if (ptepa & PG_PS)
return (NULL);
mpte = PHYS_TO_VM_PAGE(ptepa & PG_FRAME);
mpte->wire_count++;
} else {
mpte = _pmap_allocpte(pmap, ptepindex,
M_NOWAIT);
if (mpte == NULL)
return (mpte);
}
}
} else {
mpte = NULL;
}
/*
* This call to vtopte makes the assumption that we are
* entering the page into the current pmap. In order to support
* quick entry into any pmap, one would likely use pmap_pte_quick.
* But that isn't as quick as vtopte.
*/
pte = vtopte(va);
if (*pte) {
if (mpte != NULL) {
mpte->wire_count--;
mpte = NULL;
}
return (mpte);
}
/*
* Enter on the PV list if part of our managed memory.
*/
if ((m->oflags & VPO_UNMANAGED) == 0 &&
!pmap_try_insert_pv_entry(pmap, va, m)) {
if (mpte != NULL) {
free = NULL;
if (pmap_unwire_pte_hold(pmap, mpte, &free)) {
pmap_invalidate_page(pmap, va);
pmap_free_zero_pages(free);
}
mpte = NULL;
}
return (mpte);
}
/*
* Increment counters
*/
pmap->pm_stats.resident_count++;
pa = VM_PAGE_TO_PHYS(m) | pmap_cache_bits(m->md.pat_mode, 0);
#ifdef PAE
if ((prot & VM_PROT_EXECUTE) == 0)
pa |= pg_nx;
#endif
/*
* Now validate mapping with RO protection
*/
if ((m->oflags & VPO_UNMANAGED) != 0)
pte_store(pte, pa | PG_V | PG_U);
else
pte_store(pte, pa | PG_V | PG_U | PG_MANAGED);
return (mpte);
}
/*
* Make a temporary mapping for a physical address. This is only intended
* to be used for panic dumps.
*/
void *
pmap_kenter_temporary(vm_paddr_t pa, int i)
{
vm_offset_t va;
va = (vm_offset_t)crashdumpmap + (i * PAGE_SIZE);
pmap_kenter(va, pa);
invlpg(va);
return ((void *)crashdumpmap);
}
/*
* This code maps large physical mmap regions into the
* processor address space. Note that some shortcuts
* are taken, but the code works.
*/
void
pmap_object_init_pt(pmap_t pmap, vm_offset_t addr, vm_object_t object,
vm_pindex_t pindex, vm_size_t size)
{
pd_entry_t *pde;
vm_paddr_t pa, ptepa;
vm_page_t p;
int pat_mode;
VM_OBJECT_LOCK_ASSERT(object, MA_OWNED);
KASSERT(object->type == OBJT_DEVICE || object->type == OBJT_SG,
("pmap_object_init_pt: non-device object"));
if (pseflag &&
(addr & (NBPDR - 1)) == 0 && (size & (NBPDR - 1)) == 0) {
if (!vm_object_populate(object, pindex, pindex + atop(size)))
return;
p = vm_page_lookup(object, pindex);
KASSERT(p->valid == VM_PAGE_BITS_ALL,
("pmap_object_init_pt: invalid page %p", p));
pat_mode = p->md.pat_mode;
/*
* Abort the mapping if the first page is not physically
* aligned to a 2/4MB page boundary.
*/
ptepa = VM_PAGE_TO_PHYS(p);
if (ptepa & (NBPDR - 1))
return;
/*
* Skip the first page. Abort the mapping if the rest of
* the pages are not physically contiguous or have differing
* memory attributes.
*/
p = TAILQ_NEXT(p, listq);
for (pa = ptepa + PAGE_SIZE; pa < ptepa + size;
pa += PAGE_SIZE) {
KASSERT(p->valid == VM_PAGE_BITS_ALL,
("pmap_object_init_pt: invalid page %p", p));
if (pa != VM_PAGE_TO_PHYS(p) ||
pat_mode != p->md.pat_mode)
return;
p = TAILQ_NEXT(p, listq);
}
/*
* Map using 2/4MB pages. Since "ptepa" is 2/4M aligned and
* "size" is a multiple of 2/4M, adding the PAT setting to
* "pa" will not affect the termination of this loop.
*/
PMAP_LOCK(pmap);
for (pa = ptepa | pmap_cache_bits(pat_mode, 1); pa < ptepa +
size; pa += NBPDR) {
pde = pmap_pde(pmap, addr);
if (*pde == 0) {
pde_store(pde, pa | PG_PS | PG_M | PG_A |
PG_U | PG_RW | PG_V);
pmap->pm_stats.resident_count += NBPDR /
PAGE_SIZE;
pmap_pde_mappings++;
}
/* Else continue on if the PDE is already valid. */
addr += NBPDR;
}
PMAP_UNLOCK(pmap);
}
}
/*
* Routine: pmap_change_wiring
* Function: Change the wiring attribute for a map/virtual-address
* pair.
* In/out conditions:
* The mapping must already exist in the pmap.
*/
void
pmap_change_wiring(pmap_t pmap, vm_offset_t va, boolean_t wired)
{
pd_entry_t *pde;
pt_entry_t *pte;
boolean_t are_queues_locked;
are_queues_locked = FALSE;
retry:
PMAP_LOCK(pmap);
pde = pmap_pde(pmap, va);
if ((*pde & PG_PS) != 0) {
if (!wired != ((*pde & PG_W) == 0)) {
if (!are_queues_locked) {
are_queues_locked = TRUE;
if (!rw_try_wlock(&pvh_global_lock)) {
PMAP_UNLOCK(pmap);
rw_wlock(&pvh_global_lock);
goto retry;
}
}
if (!pmap_demote_pde(pmap, pde, va))
panic("pmap_change_wiring: demotion failed");
} else
goto out;
}
pte = pmap_pte(pmap, va);
if (wired && !pmap_pte_w(pte))
pmap->pm_stats.wired_count++;
else if (!wired && pmap_pte_w(pte))
pmap->pm_stats.wired_count--;
/*
* Wiring is not a hardware characteristic so there is no need to
* invalidate TLB.
*/
pmap_pte_set_w(pte, wired);
pmap_pte_release(pte);
out:
if (are_queues_locked)
rw_wunlock(&pvh_global_lock);
PMAP_UNLOCK(pmap);
}
/*
* Copy the range specified by src_addr/len
* from the source map to the range dst_addr/len
* in the destination map.
*
* This routine is only advisory and need not do anything.
*/
void
pmap_copy(pmap_t dst_pmap, pmap_t src_pmap, vm_offset_t dst_addr, vm_size_t len,
vm_offset_t src_addr)
{
vm_page_t free;
vm_offset_t addr;
vm_offset_t end_addr = src_addr + len;
vm_offset_t pdnxt;
if (dst_addr != src_addr)
return;
if (!pmap_is_current(src_pmap))
return;
rw_wlock(&pvh_global_lock);
if (dst_pmap < src_pmap) {
PMAP_LOCK(dst_pmap);
PMAP_LOCK(src_pmap);
} else {
PMAP_LOCK(src_pmap);
PMAP_LOCK(dst_pmap);
}
sched_pin();
for (addr = src_addr; addr < end_addr; addr = pdnxt) {
pt_entry_t *src_pte, *dst_pte;
vm_page_t dstmpte, srcmpte;
pd_entry_t srcptepaddr;
u_int ptepindex;
KASSERT(addr < UPT_MIN_ADDRESS,
("pmap_copy: invalid to pmap_copy page tables"));
pdnxt = (addr + NBPDR) & ~PDRMASK;
if (pdnxt < addr)
pdnxt = end_addr;
ptepindex = addr >> PDRSHIFT;
srcptepaddr = src_pmap->pm_pdir[ptepindex];
if (srcptepaddr == 0)
continue;
if (srcptepaddr & PG_PS) {
if (dst_pmap->pm_pdir[ptepindex] == 0 &&
((srcptepaddr & PG_MANAGED) == 0 ||
pmap_pv_insert_pde(dst_pmap, addr, srcptepaddr &
PG_PS_FRAME))) {
dst_pmap->pm_pdir[ptepindex] = srcptepaddr &
~PG_W;
dst_pmap->pm_stats.resident_count +=
NBPDR / PAGE_SIZE;
}
continue;
}
srcmpte = PHYS_TO_VM_PAGE(srcptepaddr & PG_FRAME);
KASSERT(srcmpte->wire_count > 0,
("pmap_copy: source page table page is unused"));
if (pdnxt > end_addr)
pdnxt = end_addr;
src_pte = vtopte(addr);
while (addr < pdnxt) {
pt_entry_t ptetemp;
ptetemp = *src_pte;
/*
* we only virtual copy managed pages
*/
if ((ptetemp & PG_MANAGED) != 0) {
dstmpte = pmap_allocpte(dst_pmap, addr,
M_NOWAIT);
if (dstmpte == NULL)
goto out;
dst_pte = pmap_pte_quick(dst_pmap, addr);
if (*dst_pte == 0 &&
pmap_try_insert_pv_entry(dst_pmap, addr,
PHYS_TO_VM_PAGE(ptetemp & PG_FRAME))) {
/*
* Clear the wired, modified, and
* accessed (referenced) bits
* during the copy.
*/
*dst_pte = ptetemp & ~(PG_W | PG_M |
PG_A);
dst_pmap->pm_stats.resident_count++;
} else {
free = NULL;
if (pmap_unwire_pte_hold(dst_pmap,
dstmpte, &free)) {
pmap_invalidate_page(dst_pmap,
addr);
pmap_free_zero_pages(free);
}
goto out;
}
if (dstmpte->wire_count >= srcmpte->wire_count)
break;
}
addr += PAGE_SIZE;
src_pte++;
}
}
out:
sched_unpin();
rw_wunlock(&pvh_global_lock);
PMAP_UNLOCK(src_pmap);
PMAP_UNLOCK(dst_pmap);
}
static __inline void
pagezero(void *page)
{
#if defined(I686_CPU)
if (cpu_class == CPUCLASS_686) {
#if defined(CPU_ENABLE_SSE)
if (cpu_feature & CPUID_SSE2)
sse2_pagezero(page);
else
#endif
i686_pagezero(page);
} else
#endif
bzero(page, PAGE_SIZE);
}
/*
* pmap_zero_page zeros the specified hardware page by mapping
* the page into KVM and using bzero to clear its contents.
*/
void
pmap_zero_page(vm_page_t m)
{
struct sysmaps *sysmaps;
sysmaps = &sysmaps_pcpu[PCPU_GET(cpuid)];
mtx_lock(&sysmaps->lock);
if (*sysmaps->CMAP2)
panic("pmap_zero_page: CMAP2 busy");
sched_pin();
*sysmaps->CMAP2 = PG_V | PG_RW | VM_PAGE_TO_PHYS(m) | PG_A | PG_M |
pmap_cache_bits(m->md.pat_mode, 0);
invlcaddr(sysmaps->CADDR2);
pagezero(sysmaps->CADDR2);
*sysmaps->CMAP2 = 0;
sched_unpin();
mtx_unlock(&sysmaps->lock);
}
/*
* pmap_zero_page_area zeros the specified hardware page by mapping
* the page into KVM and using bzero to clear its contents.
*
* off and size may not cover an area beyond a single hardware page.
*/
void
pmap_zero_page_area(vm_page_t m, int off, int size)
{
struct sysmaps *sysmaps;
sysmaps = &sysmaps_pcpu[PCPU_GET(cpuid)];
mtx_lock(&sysmaps->lock);
if (*sysmaps->CMAP2)
panic("pmap_zero_page_area: CMAP2 busy");
sched_pin();
*sysmaps->CMAP2 = PG_V | PG_RW | VM_PAGE_TO_PHYS(m) | PG_A | PG_M |
pmap_cache_bits(m->md.pat_mode, 0);
invlcaddr(sysmaps->CADDR2);
if (off == 0 && size == PAGE_SIZE)
pagezero(sysmaps->CADDR2);
else
bzero((char *)sysmaps->CADDR2 + off, size);
*sysmaps->CMAP2 = 0;
sched_unpin();
mtx_unlock(&sysmaps->lock);
}
/*
* pmap_zero_page_idle zeros the specified hardware page by mapping
* the page into KVM and using bzero to clear its contents. This
* is intended to be called from the vm_pagezero process only and
* outside of Giant.
*/
void
pmap_zero_page_idle(vm_page_t m)
{
if (*CMAP3)
panic("pmap_zero_page_idle: CMAP3 busy");
sched_pin();
*CMAP3 = PG_V | PG_RW | VM_PAGE_TO_PHYS(m) | PG_A | PG_M |
pmap_cache_bits(m->md.pat_mode, 0);
invlcaddr(CADDR3);
pagezero(CADDR3);
*CMAP3 = 0;
sched_unpin();
}
/*
* pmap_copy_page copies the specified (machine independent)
* page by mapping the page into virtual memory and using
* bcopy to copy the page, one machine dependent page at a
* time.
*/
void
pmap_copy_page(vm_page_t src, vm_page_t dst)
{
struct sysmaps *sysmaps;
sysmaps = &sysmaps_pcpu[PCPU_GET(cpuid)];
mtx_lock(&sysmaps->lock);
if (*sysmaps->CMAP1)
panic("pmap_copy_page: CMAP1 busy");
if (*sysmaps->CMAP2)
panic("pmap_copy_page: CMAP2 busy");
sched_pin();
invlpg((u_int)sysmaps->CADDR1);
invlpg((u_int)sysmaps->CADDR2);
*sysmaps->CMAP1 = PG_V | VM_PAGE_TO_PHYS(src) | PG_A |
pmap_cache_bits(src->md.pat_mode, 0);
*sysmaps->CMAP2 = PG_V | PG_RW | VM_PAGE_TO_PHYS(dst) | PG_A | PG_M |
pmap_cache_bits(dst->md.pat_mode, 0);
bcopy(sysmaps->CADDR1, sysmaps->CADDR2, PAGE_SIZE);
*sysmaps->CMAP1 = 0;
*sysmaps->CMAP2 = 0;
sched_unpin();
mtx_unlock(&sysmaps->lock);
}
/*
* Returns true if the pmap's pv is one of the first
* 16 pvs linked to from this page. This count may
* be changed upwards or downwards in the future; it
* is only necessary that true be returned for a small
* subset of pmaps for proper page aging.
*/
boolean_t
pmap_page_exists_quick(pmap_t pmap, vm_page_t m)
{
struct md_page *pvh;
pv_entry_t pv;
int loops = 0;
boolean_t rv;
KASSERT((m->oflags & VPO_UNMANAGED) == 0,
("pmap_page_exists_quick: page %p is not managed", m));
rv = FALSE;
rw_wlock(&pvh_global_lock);
TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) {
if (PV_PMAP(pv) == pmap) {
rv = TRUE;
break;
}
loops++;
if (loops >= 16)
break;
}
if (!rv && loops < 16 && (m->flags & PG_FICTITIOUS) == 0) {
pvh = pa_to_pvh(VM_PAGE_TO_PHYS(m));
TAILQ_FOREACH(pv, &pvh->pv_list, pv_list) {
if (PV_PMAP(pv) == pmap) {
rv = TRUE;
break;
}
loops++;
if (loops >= 16)
break;
}
}
rw_wunlock(&pvh_global_lock);
return (rv);
}
/*
* pmap_page_wired_mappings:
*
* Return the number of managed mappings to the given physical page
* that are wired.
*/
int
pmap_page_wired_mappings(vm_page_t m)
{
int count;
count = 0;
if ((m->oflags & VPO_UNMANAGED) != 0)
return (count);
rw_wlock(&pvh_global_lock);
count = pmap_pvh_wired_mappings(&m->md, count);
if ((m->flags & PG_FICTITIOUS) == 0) {
count = pmap_pvh_wired_mappings(pa_to_pvh(VM_PAGE_TO_PHYS(m)),
count);
}
rw_wunlock(&pvh_global_lock);
return (count);
}
/*
* pmap_pvh_wired_mappings:
*
* Return the updated number "count" of managed mappings that are wired.
*/
static int
pmap_pvh_wired_mappings(struct md_page *pvh, int count)
{
pmap_t pmap;
pt_entry_t *pte;
pv_entry_t pv;
rw_assert(&pvh_global_lock, RA_WLOCKED);
sched_pin();
TAILQ_FOREACH(pv, &pvh->pv_list, pv_list) {
pmap = PV_PMAP(pv);
PMAP_LOCK(pmap);
pte = pmap_pte_quick(pmap, pv->pv_va);
if ((*pte & PG_W) != 0)
count++;
PMAP_UNLOCK(pmap);
}
sched_unpin();
return (count);
}
/*
* Returns TRUE if the given page is mapped individually or as part of
* a 4mpage. Otherwise, returns FALSE.
*/
boolean_t
pmap_page_is_mapped(vm_page_t m)
{
boolean_t rv;
if ((m->oflags & VPO_UNMANAGED) != 0)
return (FALSE);
rw_wlock(&pvh_global_lock);
rv = !TAILQ_EMPTY(&m->md.pv_list) ||
((m->flags & PG_FICTITIOUS) == 0 &&
!TAILQ_EMPTY(&pa_to_pvh(VM_PAGE_TO_PHYS(m))->pv_list));
rw_wunlock(&pvh_global_lock);
return (rv);
}
/*
* Remove all pages from specified address space
* this aids process exit speeds. Also, this code
* is special cased for current process only, but
* can have the more generic (and slightly slower)
* mode enabled. This is much faster than pmap_remove
* in the case of running down an entire address space.
*/
void
pmap_remove_pages(pmap_t pmap)
{
pt_entry_t *pte, tpte;
vm_page_t free = NULL;
vm_page_t m, mpte, mt;
pv_entry_t pv;
struct md_page *pvh;
struct pv_chunk *pc, *npc;
int field, idx;
int32_t bit;
uint32_t inuse, bitmask;
int allfree;
if (pmap != PCPU_GET(curpmap)) {
printf("warning: pmap_remove_pages called with non-current pmap\n");
return;
}
rw_wlock(&pvh_global_lock);
PMAP_LOCK(pmap);
sched_pin();
TAILQ_FOREACH_SAFE(pc, &pmap->pm_pvchunk, pc_list, npc) {
allfree = 1;
for (field = 0; field < _NPCM; field++) {
inuse = ~pc->pc_map[field] & pc_freemask[field];
while (inuse != 0) {
bit = bsfl(inuse);
bitmask = 1UL << bit;
idx = field * 32 + bit;
pv = &pc->pc_pventry[idx];
inuse &= ~bitmask;
pte = pmap_pde(pmap, pv->pv_va);
tpte = *pte;
if ((tpte & PG_PS) == 0) {
pte = vtopte(pv->pv_va);
tpte = *pte & ~PG_PTE_PAT;
}
if (tpte == 0) {
printf(
"TPTE at %p IS ZERO @ VA %08x\n",
pte, pv->pv_va);
panic("bad pte");
}
/*
* We cannot remove wired pages from a process' mapping at this time
*/
if (tpte & PG_W) {
allfree = 0;
continue;
}
m = PHYS_TO_VM_PAGE(tpte & PG_FRAME);
KASSERT(m->phys_addr == (tpte & PG_FRAME),
("vm_page_t %p phys_addr mismatch %016jx %016jx",
m, (uintmax_t)m->phys_addr,
(uintmax_t)tpte));
KASSERT((m->flags & PG_FICTITIOUS) != 0 ||
m < &vm_page_array[vm_page_array_size],
("pmap_remove_pages: bad tpte %#jx",
(uintmax_t)tpte));
pte_clear(pte);
/*
* Update the vm_page_t clean/reference bits.
*/
if ((tpte & (PG_M | PG_RW)) == (PG_M | PG_RW)) {
if ((tpte & PG_PS) != 0) {
for (mt = m; mt < &m[NBPDR / PAGE_SIZE]; mt++)
vm_page_dirty(mt);
} else
vm_page_dirty(m);
}
/* Mark free */
PV_STAT(pv_entry_frees++);
PV_STAT(pv_entry_spare++);
pv_entry_count--;
pc->pc_map[field] |= bitmask;
if ((tpte & PG_PS) != 0) {
pmap->pm_stats.resident_count -= NBPDR / PAGE_SIZE;
pvh = pa_to_pvh(tpte & PG_PS_FRAME);
TAILQ_REMOVE(&pvh->pv_list, pv, pv_list);
if (TAILQ_EMPTY(&pvh->pv_list)) {
for (mt = m; mt < &m[NBPDR / PAGE_SIZE]; mt++)
if (TAILQ_EMPTY(&mt->md.pv_list))
vm_page_aflag_clear(mt, PGA_WRITEABLE);
}
mpte = pmap_lookup_pt_page(pmap, pv->pv_va);
if (mpte != NULL) {
pmap_remove_pt_page(pmap, mpte);
pmap->pm_stats.resident_count--;
KASSERT(mpte->wire_count == NPTEPG,
("pmap_remove_pages: pte page wire count error"));
mpte->wire_count = 0;
pmap_add_delayed_free_list(mpte, &free, FALSE);
atomic_subtract_int(&cnt.v_wire_count, 1);
}
} else {
pmap->pm_stats.resident_count--;
TAILQ_REMOVE(&m->md.pv_list, pv, pv_list);
if (TAILQ_EMPTY(&m->md.pv_list) &&
(m->flags & PG_FICTITIOUS) == 0) {
pvh = pa_to_pvh(VM_PAGE_TO_PHYS(m));
if (TAILQ_EMPTY(&pvh->pv_list))
vm_page_aflag_clear(m, PGA_WRITEABLE);
}
pmap_unuse_pt(pmap, pv->pv_va, &free);
}
}
}
if (allfree) {
TAILQ_REMOVE(&pmap->pm_pvchunk, pc, pc_list);
free_pv_chunk(pc);
}
}
sched_unpin();
pmap_invalidate_all(pmap);
rw_wunlock(&pvh_global_lock);
PMAP_UNLOCK(pmap);
pmap_free_zero_pages(free);
}
/*
* pmap_is_modified:
*
* Return whether or not the specified physical page was modified
* in any physical maps.
*/
boolean_t
pmap_is_modified(vm_page_t m)
{
boolean_t rv;
KASSERT((m->oflags & VPO_UNMANAGED) == 0,
("pmap_is_modified: page %p is not managed", m));
/*
* If the page is not VPO_BUSY, then PGA_WRITEABLE cannot be
* concurrently set while the object is locked. Thus, if PGA_WRITEABLE
* is clear, no PTEs can have PG_M set.
*/
VM_OBJECT_LOCK_ASSERT(m->object, MA_OWNED);
if ((m->oflags & VPO_BUSY) == 0 &&
(m->aflags & PGA_WRITEABLE) == 0)
return (FALSE);
rw_wlock(&pvh_global_lock);
rv = pmap_is_modified_pvh(&m->md) ||
((m->flags & PG_FICTITIOUS) == 0 &&
pmap_is_modified_pvh(pa_to_pvh(VM_PAGE_TO_PHYS(m))));
rw_wunlock(&pvh_global_lock);
return (rv);
}
/*
* Returns TRUE if any of the given mappings were used to modify
* physical memory. Otherwise, returns FALSE. Both page and 2mpage
* mappings are supported.
*/
static boolean_t
pmap_is_modified_pvh(struct md_page *pvh)
{
pv_entry_t pv;
pt_entry_t *pte;
pmap_t pmap;
boolean_t rv;
rw_assert(&pvh_global_lock, RA_WLOCKED);
rv = FALSE;
sched_pin();
TAILQ_FOREACH(pv, &pvh->pv_list, pv_list) {
pmap = PV_PMAP(pv);
PMAP_LOCK(pmap);
pte = pmap_pte_quick(pmap, pv->pv_va);
rv = (*pte & (PG_M | PG_RW)) == (PG_M | PG_RW);
PMAP_UNLOCK(pmap);
if (rv)
break;
}
sched_unpin();
return (rv);
}
/*
* pmap_is_prefaultable:
*
* Return whether or not the specified virtual address is elgible
* for prefault.
*/
boolean_t
pmap_is_prefaultable(pmap_t pmap, vm_offset_t addr)
{
pd_entry_t *pde;
pt_entry_t *pte;
boolean_t rv;
rv = FALSE;
PMAP_LOCK(pmap);
pde = pmap_pde(pmap, addr);
if (*pde != 0 && (*pde & PG_PS) == 0) {
pte = vtopte(addr);
rv = *pte == 0;
}
PMAP_UNLOCK(pmap);
return (rv);
}
/*
* pmap_is_referenced:
*
* Return whether or not the specified physical page was referenced
* in any physical maps.
*/
boolean_t
pmap_is_referenced(vm_page_t m)
{
boolean_t rv;
KASSERT((m->oflags & VPO_UNMANAGED) == 0,
("pmap_is_referenced: page %p is not managed", m));
rw_wlock(&pvh_global_lock);
rv = pmap_is_referenced_pvh(&m->md) ||
((m->flags & PG_FICTITIOUS) == 0 &&
pmap_is_referenced_pvh(pa_to_pvh(VM_PAGE_TO_PHYS(m))));
rw_wunlock(&pvh_global_lock);
return (rv);
}
/*
* Returns TRUE if any of the given mappings were referenced and FALSE
* otherwise. Both page and 4mpage mappings are supported.
*/
static boolean_t
pmap_is_referenced_pvh(struct md_page *pvh)
{
pv_entry_t pv;
pt_entry_t *pte;
pmap_t pmap;
boolean_t rv;
rw_assert(&pvh_global_lock, RA_WLOCKED);
rv = FALSE;
sched_pin();
TAILQ_FOREACH(pv, &pvh->pv_list, pv_list) {
pmap = PV_PMAP(pv);
PMAP_LOCK(pmap);
pte = pmap_pte_quick(pmap, pv->pv_va);
rv = (*pte & (PG_A | PG_V)) == (PG_A | PG_V);
PMAP_UNLOCK(pmap);
if (rv)
break;
}
sched_unpin();
return (rv);
}
/*
* Clear the write and modified bits in each of the given page's mappings.
*/
void
pmap_remove_write(vm_page_t m)
{
struct md_page *pvh;
pv_entry_t next_pv, pv;
pmap_t pmap;
pd_entry_t *pde;
pt_entry_t oldpte, *pte;
vm_offset_t va;
KASSERT((m->oflags & VPO_UNMANAGED) == 0,
("pmap_remove_write: page %p is not managed", m));
/*
* If the page is not VPO_BUSY, then PGA_WRITEABLE cannot be set by
* another thread while the object is locked. Thus, if PGA_WRITEABLE
* is clear, no page table entries need updating.
*/
VM_OBJECT_LOCK_ASSERT(m->object, MA_OWNED);
if ((m->oflags & VPO_BUSY) == 0 &&
(m->aflags & PGA_WRITEABLE) == 0)
return;
rw_wlock(&pvh_global_lock);
sched_pin();
if ((m->flags & PG_FICTITIOUS) != 0)
goto small_mappings;
pvh = pa_to_pvh(VM_PAGE_TO_PHYS(m));
TAILQ_FOREACH_SAFE(pv, &pvh->pv_list, pv_list, next_pv) {
va = pv->pv_va;
pmap = PV_PMAP(pv);
PMAP_LOCK(pmap);
pde = pmap_pde(pmap, va);
if ((*pde & PG_RW) != 0)
(void)pmap_demote_pde(pmap, pde, va);
PMAP_UNLOCK(pmap);
}
small_mappings:
TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) {
pmap = PV_PMAP(pv);
PMAP_LOCK(pmap);
pde = pmap_pde(pmap, pv->pv_va);
KASSERT((*pde & PG_PS) == 0, ("pmap_clear_write: found"
" a 4mpage in page %p's pv list", m));
pte = pmap_pte_quick(pmap, pv->pv_va);
retry:
oldpte = *pte;
if ((oldpte & PG_RW) != 0) {
/*
* Regardless of whether a pte is 32 or 64 bits
* in size, PG_RW and PG_M are among the least
* significant 32 bits.
*/
if (!atomic_cmpset_int((u_int *)pte, oldpte,
oldpte & ~(PG_RW | PG_M)))
goto retry;
if ((oldpte & PG_M) != 0)
vm_page_dirty(m);
pmap_invalidate_page(pmap, pv->pv_va);
}
PMAP_UNLOCK(pmap);
}
vm_page_aflag_clear(m, PGA_WRITEABLE);
sched_unpin();
rw_wunlock(&pvh_global_lock);
}
/*
* pmap_ts_referenced:
*
* Return a count of reference bits for a page, clearing those bits.
* It is not necessary for every reference bit to be cleared, but it
* is necessary that 0 only be returned when there are truly no
* reference bits set.
*
* XXX: The exact number of bits to check and clear is a matter that
* should be tested and standardized at some point in the future for
* optimal aging of shared pages.
*/
int
pmap_ts_referenced(vm_page_t m)
{
struct md_page *pvh;
pv_entry_t pv, pvf, pvn;
pmap_t pmap;
pd_entry_t oldpde, *pde;
pt_entry_t *pte;
vm_offset_t va;
int rtval = 0;
KASSERT((m->oflags & VPO_UNMANAGED) == 0,
("pmap_ts_referenced: page %p is not managed", m));
pvh = pa_to_pvh(VM_PAGE_TO_PHYS(m));
rw_wlock(&pvh_global_lock);
sched_pin();
if ((m->flags & PG_FICTITIOUS) != 0)
goto small_mappings;
TAILQ_FOREACH_SAFE(pv, &pvh->pv_list, pv_list, pvn) {
va = pv->pv_va;
pmap = PV_PMAP(pv);
PMAP_LOCK(pmap);
pde = pmap_pde(pmap, va);
oldpde = *pde;
if ((oldpde & PG_A) != 0) {
if (pmap_demote_pde(pmap, pde, va)) {
if ((oldpde & PG_W) == 0) {
/*
* Remove the mapping to a single page
* so that a subsequent access may
* repromote. Since the underlying
* page table page is fully populated,
* this removal never frees a page
* table page.
*/
va += VM_PAGE_TO_PHYS(m) - (oldpde &
PG_PS_FRAME);
pmap_remove_page(pmap, va, NULL);
rtval++;
if (rtval > 4) {
PMAP_UNLOCK(pmap);
goto out;
}
}
}
}
PMAP_UNLOCK(pmap);
}
small_mappings:
if ((pv = TAILQ_FIRST(&m->md.pv_list)) != NULL) {
pvf = pv;
do {
pvn = TAILQ_NEXT(pv, pv_list);
TAILQ_REMOVE(&m->md.pv_list, pv, pv_list);
TAILQ_INSERT_TAIL(&m->md.pv_list, pv, pv_list);
pmap = PV_PMAP(pv);
PMAP_LOCK(pmap);
pde = pmap_pde(pmap, pv->pv_va);
KASSERT((*pde & PG_PS) == 0, ("pmap_ts_referenced:"
" found a 4mpage in page %p's pv list", m));
pte = pmap_pte_quick(pmap, pv->pv_va);
if ((*pte & PG_A) != 0) {
atomic_clear_int((u_int *)pte, PG_A);
pmap_invalidate_page(pmap, pv->pv_va);
rtval++;
if (rtval > 4)
pvn = NULL;
}
PMAP_UNLOCK(pmap);
} while ((pv = pvn) != NULL && pv != pvf);
}
out:
sched_unpin();
rw_wunlock(&pvh_global_lock);
return (rtval);
}
/*
* Clear the modify bits on the specified physical page.
*/
void
pmap_clear_modify(vm_page_t m)
{
struct md_page *pvh;
pv_entry_t next_pv, pv;
pmap_t pmap;
pd_entry_t oldpde, *pde;
pt_entry_t oldpte, *pte;
vm_offset_t va;
KASSERT((m->oflags & VPO_UNMANAGED) == 0,
("pmap_clear_modify: page %p is not managed", m));
VM_OBJECT_LOCK_ASSERT(m->object, MA_OWNED);
KASSERT((m->oflags & VPO_BUSY) == 0,
("pmap_clear_modify: page %p is busy", m));
/*
* If the page is not PGA_WRITEABLE, then no PTEs can have PG_M set.
* If the object containing the page is locked and the page is not
* VPO_BUSY, then PGA_WRITEABLE cannot be concurrently set.
*/
if ((m->aflags & PGA_WRITEABLE) == 0)
return;
rw_wlock(&pvh_global_lock);
sched_pin();
if ((m->flags & PG_FICTITIOUS) != 0)
goto small_mappings;
pvh = pa_to_pvh(VM_PAGE_TO_PHYS(m));
TAILQ_FOREACH_SAFE(pv, &pvh->pv_list, pv_list, next_pv) {
va = pv->pv_va;
pmap = PV_PMAP(pv);
PMAP_LOCK(pmap);
pde = pmap_pde(pmap, va);
oldpde = *pde;
if ((oldpde & PG_RW) != 0) {
if (pmap_demote_pde(pmap, pde, va)) {
if ((oldpde & PG_W) == 0) {
/*
* Write protect the mapping to a
* single page so that a subsequent
* write access may repromote.
*/
va += VM_PAGE_TO_PHYS(m) - (oldpde &
PG_PS_FRAME);
pte = pmap_pte_quick(pmap, va);
oldpte = *pte;
if ((oldpte & PG_V) != 0) {
/*
* Regardless of whether a pte is 32 or 64 bits
* in size, PG_RW and PG_M are among the least
* significant 32 bits.
*/
while (!atomic_cmpset_int((u_int *)pte,
oldpte,
oldpte & ~(PG_M | PG_RW)))
oldpte = *pte;
vm_page_dirty(m);
pmap_invalidate_page(pmap, va);
}
}
}
}
PMAP_UNLOCK(pmap);
}
small_mappings:
TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) {
pmap = PV_PMAP(pv);
PMAP_LOCK(pmap);
pde = pmap_pde(pmap, pv->pv_va);
KASSERT((*pde & PG_PS) == 0, ("pmap_clear_modify: found"
" a 4mpage in page %p's pv list", m));
pte = pmap_pte_quick(pmap, pv->pv_va);
if ((*pte & (PG_M | PG_RW)) == (PG_M | PG_RW)) {
/*
* Regardless of whether a pte is 32 or 64 bits
* in size, PG_M is among the least significant
* 32 bits.
*/
atomic_clear_int((u_int *)pte, PG_M);
pmap_invalidate_page(pmap, pv->pv_va);
}
PMAP_UNLOCK(pmap);
}
sched_unpin();
rw_wunlock(&pvh_global_lock);
}
/*
* pmap_clear_reference:
*
* Clear the reference bit on the specified physical page.
*/
void
pmap_clear_reference(vm_page_t m)
{
struct md_page *pvh;
pv_entry_t next_pv, pv;
pmap_t pmap;
pd_entry_t oldpde, *pde;
pt_entry_t *pte;
vm_offset_t va;
KASSERT((m->oflags & VPO_UNMANAGED) == 0,
("pmap_clear_reference: page %p is not managed", m));
rw_wlock(&pvh_global_lock);
sched_pin();
if ((m->flags & PG_FICTITIOUS) != 0)
goto small_mappings;
pvh = pa_to_pvh(VM_PAGE_TO_PHYS(m));
TAILQ_FOREACH_SAFE(pv, &pvh->pv_list, pv_list, next_pv) {
va = pv->pv_va;
pmap = PV_PMAP(pv);
PMAP_LOCK(pmap);
pde = pmap_pde(pmap, va);
oldpde = *pde;
if ((oldpde & PG_A) != 0) {
if (pmap_demote_pde(pmap, pde, va)) {
/*
* Remove the mapping to a single page so
* that a subsequent access may repromote.
* Since the underlying page table page is
* fully populated, this removal never frees
* a page table page.
*/
va += VM_PAGE_TO_PHYS(m) - (oldpde &
PG_PS_FRAME);
pmap_remove_page(pmap, va, NULL);
}
}
PMAP_UNLOCK(pmap);
}
small_mappings:
TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) {
pmap = PV_PMAP(pv);
PMAP_LOCK(pmap);
pde = pmap_pde(pmap, pv->pv_va);
KASSERT((*pde & PG_PS) == 0, ("pmap_clear_reference: found"
" a 4mpage in page %p's pv list", m));
pte = pmap_pte_quick(pmap, pv->pv_va);
if ((*pte & PG_A) != 0) {
/*
* Regardless of whether a pte is 32 or 64 bits
* in size, PG_A is among the least significant
* 32 bits.
*/
atomic_clear_int((u_int *)pte, PG_A);
pmap_invalidate_page(pmap, pv->pv_va);
}
PMAP_UNLOCK(pmap);
}
sched_unpin();
rw_wunlock(&pvh_global_lock);
}
/*
* Miscellaneous support routines follow
*/
/* Adjust the cache mode for a 4KB page mapped via a PTE. */
static __inline void
pmap_pte_attr(pt_entry_t *pte, int cache_bits)
{
u_int opte, npte;
/*
* The cache mode bits are all in the low 32-bits of the
* PTE, so we can just spin on updating the low 32-bits.
*/
do {
opte = *(u_int *)pte;
npte = opte & ~PG_PTE_CACHE;
npte |= cache_bits;
} while (npte != opte && !atomic_cmpset_int((u_int *)pte, opte, npte));
}
/* Adjust the cache mode for a 2/4MB page mapped via a PDE. */
static __inline void
pmap_pde_attr(pd_entry_t *pde, int cache_bits)
{
u_int opde, npde;
/*
* The cache mode bits are all in the low 32-bits of the
* PDE, so we can just spin on updating the low 32-bits.
*/
do {
opde = *(u_int *)pde;
npde = opde & ~PG_PDE_CACHE;
npde |= cache_bits;
} while (npde != opde && !atomic_cmpset_int((u_int *)pde, opde, npde));
}
/*
* Map a set of physical memory pages into the kernel virtual
* address space. Return a pointer to where it is mapped. This
* routine is intended to be used for mapping device memory,
* NOT real memory.
*/
void *
pmap_mapdev_attr(vm_paddr_t pa, vm_size_t size, int mode)
{
vm_offset_t va, offset;
vm_size_t tmpsize;
offset = pa & PAGE_MASK;
size = roundup(offset + size, PAGE_SIZE);
pa = pa & PG_FRAME;
if (pa < KERNLOAD && pa + size <= KERNLOAD)
va = KERNBASE + pa;
else
va = kmem_alloc_nofault(kernel_map, size);
if (!va)
panic("pmap_mapdev: Couldn't alloc kernel virtual memory");
for (tmpsize = 0; tmpsize < size; tmpsize += PAGE_SIZE)
pmap_kenter_attr(va + tmpsize, pa + tmpsize, mode);
pmap_invalidate_range(kernel_pmap, va, va + tmpsize);
pmap_invalidate_cache_range(va, va + size);
return ((void *)(va + offset));
}
void *
pmap_mapdev(vm_paddr_t pa, vm_size_t size)
{
return (pmap_mapdev_attr(pa, size, PAT_UNCACHEABLE));
}
void *
pmap_mapbios(vm_paddr_t pa, vm_size_t size)
{
return (pmap_mapdev_attr(pa, size, PAT_WRITE_BACK));
}
void
pmap_unmapdev(vm_offset_t va, vm_size_t size)
{
vm_offset_t base, offset, tmpva;
if (va >= KERNBASE && va + size <= KERNBASE + KERNLOAD)
return;
base = trunc_page(va);
offset = va & PAGE_MASK;
size = roundup(offset + size, PAGE_SIZE);
for (tmpva = base; tmpva < (base + size); tmpva += PAGE_SIZE)
pmap_kremove(tmpva);
pmap_invalidate_range(kernel_pmap, va, tmpva);
kmem_free(kernel_map, base, size);
}
/*
* Sets the memory attribute for the specified page.
*/
void
pmap_page_set_memattr(vm_page_t m, vm_memattr_t ma)
{
m->md.pat_mode = ma;
if ((m->flags & PG_FICTITIOUS) != 0)
return;
/*
* If "m" is a normal page, flush it from the cache.
* See pmap_invalidate_cache_range().
*
* First, try to find an existing mapping of the page by sf
* buffer. sf_buf_invalidate_cache() modifies mapping and
* flushes the cache.
*/
if (sf_buf_invalidate_cache(m))
return;
/*
* If page is not mapped by sf buffer, but CPU does not
* support self snoop, map the page transient and do
* invalidation. In the worst case, whole cache is flushed by
* pmap_invalidate_cache_range().
*/
if ((cpu_feature & CPUID_SS) == 0)
pmap_flush_page(m);
}
static void
pmap_flush_page(vm_page_t m)
{
struct sysmaps *sysmaps;
vm_offset_t sva, eva;
if ((cpu_feature & CPUID_CLFSH) != 0) {
sysmaps = &sysmaps_pcpu[PCPU_GET(cpuid)];
mtx_lock(&sysmaps->lock);
if (*sysmaps->CMAP2)
panic("pmap_flush_page: CMAP2 busy");
sched_pin();
*sysmaps->CMAP2 = PG_V | PG_RW | VM_PAGE_TO_PHYS(m) |
PG_A | PG_M | pmap_cache_bits(m->md.pat_mode, 0);
invlcaddr(sysmaps->CADDR2);
sva = (vm_offset_t)sysmaps->CADDR2;
eva = sva + PAGE_SIZE;
/*
* Use mfence despite the ordering implied by
* mtx_{un,}lock() because clflush is not guaranteed
* to be ordered by any other instruction.
*/
mfence();
for (; sva < eva; sva += cpu_clflush_line_size)
clflush(sva);
mfence();
*sysmaps->CMAP2 = 0;
sched_unpin();
mtx_unlock(&sysmaps->lock);
} else
pmap_invalidate_cache();
}
/*
* Changes the specified virtual address range's memory type to that given by
* the parameter "mode". The specified virtual address range must be
* completely contained within either the kernel map.
*
* Returns zero if the change completed successfully, and either EINVAL or
* ENOMEM if the change failed. Specifically, EINVAL is returned if some part
* of the virtual address range was not mapped, and ENOMEM is returned if
* there was insufficient memory available to complete the change.
*/
int
pmap_change_attr(vm_offset_t va, vm_size_t size, int mode)
{
vm_offset_t base, offset, tmpva;
pd_entry_t *pde;
pt_entry_t *pte;
int cache_bits_pte, cache_bits_pde;
boolean_t changed;
base = trunc_page(va);
offset = va & PAGE_MASK;
size = roundup(offset + size, PAGE_SIZE);
/*
* Only supported on kernel virtual addresses above the recursive map.
*/
if (base < VM_MIN_KERNEL_ADDRESS)
return (EINVAL);
cache_bits_pde = pmap_cache_bits(mode, 1);
cache_bits_pte = pmap_cache_bits(mode, 0);
changed = FALSE;
/*
* Pages that aren't mapped aren't supported. Also break down
* 2/4MB pages into 4KB pages if required.
*/
PMAP_LOCK(kernel_pmap);
for (tmpva = base; tmpva < base + size; ) {
pde = pmap_pde(kernel_pmap, tmpva);
if (*pde == 0) {
PMAP_UNLOCK(kernel_pmap);
return (EINVAL);
}
if (*pde & PG_PS) {
/*
* If the current 2/4MB page already has
* the required memory type, then we need not
* demote this page. Just increment tmpva to
* the next 2/4MB page frame.
*/
if ((*pde & PG_PDE_CACHE) == cache_bits_pde) {
tmpva = trunc_4mpage(tmpva) + NBPDR;
continue;
}
/*
* If the current offset aligns with a 2/4MB
* page frame and there is at least 2/4MB left
* within the range, then we need not break
* down this page into 4KB pages.
*/
if ((tmpva & PDRMASK) == 0 &&
tmpva + PDRMASK < base + size) {
tmpva += NBPDR;
continue;
}
if (!pmap_demote_pde(kernel_pmap, pde, tmpva)) {
PMAP_UNLOCK(kernel_pmap);
return (ENOMEM);
}
}
pte = vtopte(tmpva);
if (*pte == 0) {
PMAP_UNLOCK(kernel_pmap);
return (EINVAL);
}
tmpva += PAGE_SIZE;
}
PMAP_UNLOCK(kernel_pmap);
/*
* Ok, all the pages exist, so run through them updating their
* cache mode if required.
*/
for (tmpva = base; tmpva < base + size; ) {
pde = pmap_pde(kernel_pmap, tmpva);
if (*pde & PG_PS) {
if ((*pde & PG_PDE_CACHE) != cache_bits_pde) {
pmap_pde_attr(pde, cache_bits_pde);
changed = TRUE;
}
tmpva = trunc_4mpage(tmpva) + NBPDR;
} else {
pte = vtopte(tmpva);
if ((*pte & PG_PTE_CACHE) != cache_bits_pte) {
pmap_pte_attr(pte, cache_bits_pte);
changed = TRUE;
}
tmpva += PAGE_SIZE;
}
}
/*
* Flush CPU caches to make sure any data isn't cached that
* shouldn't be, etc.
*/
if (changed) {
pmap_invalidate_range(kernel_pmap, base, tmpva);
pmap_invalidate_cache_range(base, tmpva);
}
return (0);
}
/*
* perform the pmap work for mincore
*/
int
pmap_mincore(pmap_t pmap, vm_offset_t addr, vm_paddr_t *locked_pa)
{
pd_entry_t *pdep;
pt_entry_t *ptep, pte;
vm_paddr_t pa;
int val;
PMAP_LOCK(pmap);
retry:
pdep = pmap_pde(pmap, addr);
if (*pdep != 0) {
if (*pdep & PG_PS) {
pte = *pdep;
/* Compute the physical address of the 4KB page. */
pa = ((*pdep & PG_PS_FRAME) | (addr & PDRMASK)) &
PG_FRAME;
val = MINCORE_SUPER;
} else {
ptep = pmap_pte(pmap, addr);
pte = *ptep;
pmap_pte_release(ptep);
pa = pte & PG_FRAME;
val = 0;
}
} else {
pte = 0;
pa = 0;
val = 0;
}
if ((pte & PG_V) != 0) {
val |= MINCORE_INCORE;
if ((pte & (PG_M | PG_RW)) == (PG_M | PG_RW))
val |= MINCORE_MODIFIED | MINCORE_MODIFIED_OTHER;
if ((pte & PG_A) != 0)
val |= MINCORE_REFERENCED | MINCORE_REFERENCED_OTHER;
}
if ((val & (MINCORE_MODIFIED_OTHER | MINCORE_REFERENCED_OTHER)) !=
(MINCORE_MODIFIED_OTHER | MINCORE_REFERENCED_OTHER) &&
(pte & (PG_MANAGED | PG_V)) == (PG_MANAGED | PG_V)) {
/* Ensure that "PHYS_TO_VM_PAGE(pa)->object" doesn't change. */
if (vm_page_pa_tryrelock(pmap, pa, locked_pa))
goto retry;
} else
PA_UNLOCK_COND(*locked_pa);
PMAP_UNLOCK(pmap);
return (val);
}
void
pmap_activate(struct thread *td)
{
pmap_t pmap, oldpmap;
u_int cpuid;
u_int32_t cr3;
critical_enter();
pmap = vmspace_pmap(td->td_proc->p_vmspace);
oldpmap = PCPU_GET(curpmap);
cpuid = PCPU_GET(cpuid);
#if defined(SMP)
CPU_CLR_ATOMIC(cpuid, &oldpmap->pm_active);
CPU_SET_ATOMIC(cpuid, &pmap->pm_active);
#else
CPU_CLR(cpuid, &oldpmap->pm_active);
CPU_SET(cpuid, &pmap->pm_active);
#endif
#ifdef PAE
cr3 = vtophys(pmap->pm_pdpt);
#else
cr3 = vtophys(pmap->pm_pdir);
#endif
/*
* pmap_activate is for the current thread on the current cpu
*/
td->td_pcb->pcb_cr3 = cr3;
load_cr3(cr3);
PCPU_SET(curpmap, pmap);
critical_exit();
}
void
pmap_sync_icache(pmap_t pm, vm_offset_t va, vm_size_t sz)
{
}
/*
* Increase the starting virtual address of the given mapping if a
* different alignment might result in more superpage mappings.
*/
void
pmap_align_superpage(vm_object_t object, vm_ooffset_t offset,
vm_offset_t *addr, vm_size_t size)
{
vm_offset_t superpage_offset;
if (size < NBPDR)
return;
if (object != NULL && (object->flags & OBJ_COLORED) != 0)
offset += ptoa(object->pg_color);
superpage_offset = offset & PDRMASK;
if (size - ((NBPDR - superpage_offset) & PDRMASK) < NBPDR ||
(*addr & PDRMASK) == superpage_offset)
return;
if ((*addr & PDRMASK) < superpage_offset)
*addr = (*addr & ~PDRMASK) + superpage_offset;
else
*addr = ((*addr + PDRMASK) & ~PDRMASK) + superpage_offset;
}
#if defined(PMAP_DEBUG)
pmap_pid_dump(int pid)
{
pmap_t pmap;
struct proc *p;
int npte = 0;
int index;
sx_slock(&allproc_lock);
FOREACH_PROC_IN_SYSTEM(p) {
if (p->p_pid != pid)
continue;
if (p->p_vmspace) {
int i,j;
index = 0;
pmap = vmspace_pmap(p->p_vmspace);
for (i = 0; i < NPDEPTD; i++) {
pd_entry_t *pde;
pt_entry_t *pte;
vm_offset_t base = i << PDRSHIFT;
pde = &pmap->pm_pdir[i];
if (pde && pmap_pde_v(pde)) {
for (j = 0; j < NPTEPG; j++) {
vm_offset_t va = base + (j << PAGE_SHIFT);
if (va >= (vm_offset_t) VM_MIN_KERNEL_ADDRESS) {
if (index) {
index = 0;
printf("\n");
}
sx_sunlock(&allproc_lock);
return (npte);
}
pte = pmap_pte(pmap, va);
if (pte && pmap_pte_v(pte)) {
pt_entry_t pa;
vm_page_t m;
pa = *pte;
m = PHYS_TO_VM_PAGE(pa & PG_FRAME);
printf("va: 0x%x, pt: 0x%x, h: %d, w: %d, f: 0x%x",
va, pa, m->hold_count, m->wire_count, m->flags);
npte++;
index++;
if (index >= 2) {
index = 0;
printf("\n");
} else {
printf(" ");
}
}
}
}
}
}
}
sx_sunlock(&allproc_lock);
return (npte);
}
#endif
#if defined(DEBUG)
static void pads(pmap_t pm);
void pmap_pvdump(vm_paddr_t pa);
/* print address space of pmap*/
static void
pads(pmap_t pm)
{
int i, j;
vm_paddr_t va;
pt_entry_t *ptep;
if (pm == kernel_pmap)
return;
for (i = 0; i < NPDEPTD; i++)
if (pm->pm_pdir[i])
for (j = 0; j < NPTEPG; j++) {
va = (i << PDRSHIFT) + (j << PAGE_SHIFT);
if (pm == kernel_pmap && va < KERNBASE)
continue;
if (pm != kernel_pmap && va > UPT_MAX_ADDRESS)
continue;
ptep = pmap_pte(pm, va);
if (pmap_pte_v(ptep))
printf("%x:%x ", va, *ptep);
};
}
void
pmap_pvdump(vm_paddr_t pa)
{
pv_entry_t pv;
pmap_t pmap;
vm_page_t m;
printf("pa %x", pa);
m = PHYS_TO_VM_PAGE(pa);
TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) {
pmap = PV_PMAP(pv);
printf(" -> pmap %p, va %x", (void *)pmap, pv->pv_va);
pads(pmap);
}
printf(" ");
}
#endif