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Current File : //sys/amd64/amd64/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) 2003 Peter Wemm * 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/amd64/amd64/pmap.c 238006 2012-07-02 17:37:40Z 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_pmap.h" #include "opt_vm.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/mutex.h> #include <sys/proc.h> #include <sys/rwlock.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 #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)]) struct pmap kernel_pmap_store; 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) */ static int ndmpdp; static vm_paddr_t dmaplimit; vm_offset_t kernel_vm_end = VM_MIN_KERNEL_ADDRESS; pt_entry_t pg_nx; 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 */ static u_int64_t KPTphys; /* phys addr of kernel level 1 */ static u_int64_t KPDphys; /* phys addr of kernel level 2 */ u_int64_t KPDPphys; /* phys addr of kernel level 3 */ u_int64_t KPML4phys; /* phys addr of kernel level 4 */ static u_int64_t DMPDphys; /* phys addr of direct mapped level 2 */ static u_int64_t DMPDPphys; /* phys addr of direct mapped level 3 */ /* * 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 long pv_entry_count; static struct md_page *pv_table; /* * All those kernel PT submaps that BSD is so fond of */ pt_entry_t *CMAP1 = 0; caddr_t CADDR1 = 0; /* * Crashdump maps. */ static caddr_t crashdumpmap; 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 int pmap_change_attr_locked(vm_offset_t va, vm_size_t size, int mode); static boolean_t pmap_demote_pde(pmap_t pmap, pd_entry_t *pde, vm_offset_t va); static boolean_t pmap_demote_pdpe(pmap_t pmap, pdp_entry_t *pdpe, 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_fill_ptp(pt_entry_t *firstpte, pt_entry_t newpte); static void pmap_insert_pt_page(pmap_t pmap, vm_page_t mpte); 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 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 int 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, pd_entry_t ptepde, vm_page_t *free); static void pmap_remove_pt_page(pmap_t pmap, vm_page_t mpte); static void pmap_remove_page(pmap_t pmap, vm_offset_t va, pd_entry_t *pde, 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_allocpde(pmap_t pmap, vm_offset_t va, int flags); static vm_page_t pmap_allocpte(pmap_t pmap, vm_offset_t va, int flags); static vm_page_t _pmap_allocpte(pmap_t pmap, vm_pindex_t ptepindex, int flags); static int _pmap_unwire_pte_hold(pmap_t pmap, vm_offset_t va, vm_page_t m, vm_page_t* free); static int pmap_unuse_pt(pmap_t, vm_offset_t, pd_entry_t, vm_page_t *); static vm_offset_t pmap_kmem_choose(vm_offset_t addr); CTASSERT(1 << PDESHIFT == sizeof(pd_entry_t)); CTASSERT(1 << PTESHIFT == sizeof(pt_entry_t)); /* * Move the kernel virtual free pointer to the next * 2MB. This is used to help improve performance * by using a large (2MB) page for much of the kernel * (.text, .data, .bss) */ static vm_offset_t pmap_kmem_choose(vm_offset_t addr) { vm_offset_t newaddr = addr; newaddr = (addr + (NBPDR - 1)) & ~(NBPDR - 1); return (newaddr); } /********************/ /* Inline functions */ /********************/ /* Return a non-clipped PD index for a given VA */ static __inline vm_pindex_t pmap_pde_pindex(vm_offset_t va) { return (va >> PDRSHIFT); } /* Return various clipped indexes for a given VA */ static __inline vm_pindex_t pmap_pte_index(vm_offset_t va) { return ((va >> PAGE_SHIFT) & ((1ul << NPTEPGSHIFT) - 1)); } static __inline vm_pindex_t pmap_pde_index(vm_offset_t va) { return ((va >> PDRSHIFT) & ((1ul << NPDEPGSHIFT) - 1)); } static __inline vm_pindex_t pmap_pdpe_index(vm_offset_t va) { return ((va >> PDPSHIFT) & ((1ul << NPDPEPGSHIFT) - 1)); } static __inline vm_pindex_t pmap_pml4e_index(vm_offset_t va) { return ((va >> PML4SHIFT) & ((1ul << NPML4EPGSHIFT) - 1)); } /* Return a pointer to the PML4 slot that corresponds to a VA */ static __inline pml4_entry_t * pmap_pml4e(pmap_t pmap, vm_offset_t va) { return (&pmap->pm_pml4[pmap_pml4e_index(va)]); } /* Return a pointer to the PDP slot that corresponds to a VA */ static __inline pdp_entry_t * pmap_pml4e_to_pdpe(pml4_entry_t *pml4e, vm_offset_t va) { pdp_entry_t *pdpe; pdpe = (pdp_entry_t *)PHYS_TO_DMAP(*pml4e & PG_FRAME); return (&pdpe[pmap_pdpe_index(va)]); } /* Return a pointer to the PDP slot that corresponds to a VA */ static __inline pdp_entry_t * pmap_pdpe(pmap_t pmap, vm_offset_t va) { pml4_entry_t *pml4e; pml4e = pmap_pml4e(pmap, va); if ((*pml4e & PG_V) == 0) return (NULL); return (pmap_pml4e_to_pdpe(pml4e, va)); } /* Return a pointer to the PD slot that corresponds to a VA */ static __inline pd_entry_t * pmap_pdpe_to_pde(pdp_entry_t *pdpe, vm_offset_t va) { pd_entry_t *pde; pde = (pd_entry_t *)PHYS_TO_DMAP(*pdpe & PG_FRAME); return (&pde[pmap_pde_index(va)]); } /* Return a pointer to the PD slot that corresponds to a VA */ static __inline pd_entry_t * pmap_pde(pmap_t pmap, vm_offset_t va) { pdp_entry_t *pdpe; pdpe = pmap_pdpe(pmap, va); if (pdpe == NULL || (*pdpe & PG_V) == 0) return (NULL); return (pmap_pdpe_to_pde(pdpe, va)); } /* Return a pointer to the PT slot that corresponds to a VA */ static __inline pt_entry_t * pmap_pde_to_pte(pd_entry_t *pde, vm_offset_t va) { pt_entry_t *pte; pte = (pt_entry_t *)PHYS_TO_DMAP(*pde & PG_FRAME); return (&pte[pmap_pte_index(va)]); } /* Return a pointer to the PT slot that corresponds to a VA */ static __inline pt_entry_t * pmap_pte(pmap_t pmap, vm_offset_t va) { pd_entry_t *pde; pde = pmap_pde(pmap, va); if (pde == NULL || (*pde & PG_V) == 0) return (NULL); if ((*pde & PG_PS) != 0) /* compat with i386 pmap_pte() */ return ((pt_entry_t *)pde); return (pmap_pde_to_pte(pde, va)); } static __inline void pmap_resident_count_inc(pmap_t pmap, int count) { PMAP_LOCK_ASSERT(pmap, MA_OWNED); pmap->pm_stats.resident_count += count; } static __inline void pmap_resident_count_dec(pmap_t pmap, int count) { PMAP_LOCK_ASSERT(pmap, MA_OWNED); pmap->pm_stats.resident_count -= count; } PMAP_INLINE pt_entry_t * vtopte(vm_offset_t va) { u_int64_t mask = ((1ul << (NPTEPGSHIFT + NPDEPGSHIFT + NPDPEPGSHIFT + NPML4EPGSHIFT)) - 1); return (PTmap + ((va >> PAGE_SHIFT) & mask)); } static __inline pd_entry_t * vtopde(vm_offset_t va) { u_int64_t mask = ((1ul << (NPDEPGSHIFT + NPDPEPGSHIFT + NPML4EPGSHIFT)) - 1); return (PDmap + ((va >> PDRSHIFT) & mask)); } static u_int64_t allocpages(vm_paddr_t *firstaddr, int n) { u_int64_t ret; ret = *firstaddr; bzero((void *)ret, n * PAGE_SIZE); *firstaddr += n * PAGE_SIZE; return (ret); } CTASSERT(powerof2(NDMPML4E)); static void create_pagetables(vm_paddr_t *firstaddr) { int i, j, ndm1g; /* Allocate pages */ KPTphys = allocpages(firstaddr, NKPT); KPML4phys = allocpages(firstaddr, 1); KPDPphys = allocpages(firstaddr, NKPML4E); KPDphys = allocpages(firstaddr, NKPDPE); ndmpdp = (ptoa(Maxmem) + NBPDP - 1) >> PDPSHIFT; if (ndmpdp < 4) /* Minimum 4GB of dirmap */ ndmpdp = 4; DMPDPphys = allocpages(firstaddr, NDMPML4E); ndm1g = 0; if ((amd_feature & AMDID_PAGE1GB) != 0) ndm1g = ptoa(Maxmem) >> PDPSHIFT; if (ndm1g < ndmpdp) DMPDphys = allocpages(firstaddr, ndmpdp - ndm1g); dmaplimit = (vm_paddr_t)ndmpdp << PDPSHIFT; /* Fill in the underlying page table pages */ /* Read-only from zero to physfree */ /* XXX not fully used, underneath 2M pages */ for (i = 0; (i << PAGE_SHIFT) < *firstaddr; i++) { ((pt_entry_t *)KPTphys)[i] = i << PAGE_SHIFT; ((pt_entry_t *)KPTphys)[i] |= PG_RW | PG_V | PG_G; } /* Now map the page tables at their location within PTmap */ for (i = 0; i < NKPT; i++) { ((pd_entry_t *)KPDphys)[i] = KPTphys + (i << PAGE_SHIFT); ((pd_entry_t *)KPDphys)[i] |= PG_RW | PG_V; } /* Map from zero to end of allocations under 2M pages */ /* This replaces some of the KPTphys entries above */ for (i = 0; (i << PDRSHIFT) < *firstaddr; i++) { ((pd_entry_t *)KPDphys)[i] = i << PDRSHIFT; ((pd_entry_t *)KPDphys)[i] |= PG_RW | PG_V | PG_PS | PG_G; } /* And connect up the PD to the PDP */ for (i = 0; i < NKPDPE; i++) { ((pdp_entry_t *)KPDPphys)[i + KPDPI] = KPDphys + (i << PAGE_SHIFT); ((pdp_entry_t *)KPDPphys)[i + KPDPI] |= PG_RW | PG_V | PG_U; } /* * Now, set up the direct map region using 2MB and/or 1GB pages. If * the end of physical memory is not aligned to a 1GB page boundary, * then the residual physical memory is mapped with 2MB pages. Later, * if pmap_mapdev{_attr}() uses the direct map for non-write-back * memory, pmap_change_attr() will demote any 2MB or 1GB page mappings * that are partially used. */ for (i = NPDEPG * ndm1g, j = 0; i < NPDEPG * ndmpdp; i++, j++) { ((pd_entry_t *)DMPDphys)[j] = (vm_paddr_t)i << PDRSHIFT; /* Preset PG_M and PG_A because demotion expects it. */ ((pd_entry_t *)DMPDphys)[j] |= PG_RW | PG_V | PG_PS | PG_G | PG_M | PG_A; } for (i = 0; i < ndm1g; i++) { ((pdp_entry_t *)DMPDPphys)[i] = (vm_paddr_t)i << PDPSHIFT; /* Preset PG_M and PG_A because demotion expects it. */ ((pdp_entry_t *)DMPDPphys)[i] |= PG_RW | PG_V | PG_PS | PG_G | PG_M | PG_A; } for (j = 0; i < ndmpdp; i++, j++) { ((pdp_entry_t *)DMPDPphys)[i] = DMPDphys + (j << PAGE_SHIFT); ((pdp_entry_t *)DMPDPphys)[i] |= PG_RW | PG_V | PG_U; } /* And recursively map PML4 to itself in order to get PTmap */ ((pdp_entry_t *)KPML4phys)[PML4PML4I] = KPML4phys; ((pdp_entry_t *)KPML4phys)[PML4PML4I] |= PG_RW | PG_V | PG_U; /* Connect the Direct Map slot(s) up to the PML4. */ for (i = 0; i < NDMPML4E; i++) { ((pdp_entry_t *)KPML4phys)[DMPML4I + i] = DMPDPphys + (i << PAGE_SHIFT); ((pdp_entry_t *)KPML4phys)[DMPML4I + i] |= PG_RW | PG_V | PG_U; } /* Connect the KVA slot up to the PML4 */ ((pdp_entry_t *)KPML4phys)[KPML4I] = KPDPphys; ((pdp_entry_t *)KPML4phys)[KPML4I] |= PG_RW | PG_V | PG_U; } /* * Bootstrap the system enough to run with virtual memory. * * On amd64 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; /* * Create an initial set of page tables to run the kernel in. */ create_pagetables(firstaddr); virtual_avail = (vm_offset_t) KERNBASE + *firstaddr; virtual_avail = pmap_kmem_choose(virtual_avail); virtual_end = VM_MAX_KERNEL_ADDRESS; /* XXX do %cr0 as well */ load_cr4(rcr4() | CR4_PGE | CR4_PSE); load_cr3(KPML4phys); /* * Initialize the kernel pmap (which is statically allocated). */ PMAP_LOCK_INIT(kernel_pmap); kernel_pmap->pm_pml4 = (pdp_entry_t *)PHYS_TO_DMAP(KPML4phys); 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"); /* * 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 is only used for the memory test. */ SYSMAP(caddr_t, CMAP1, CADDR1, 1) /* * Crashdump maps. */ SYSMAP(caddr_t, unused, crashdumpmap, MAXDUMPPGS) virtual_avail = va; /* Initialize the PAT MSR. */ pmap_init_pat(); } /* * 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; /* Bail if this CPU doesn't implement PAT. */ if ((cpu_feature & CPUID_PAT) == 0) panic("no PAT??"); /* 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; /* 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); } /* * 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; } /* * 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 = pmap_pde_pindex(KERNBASE) + i; mpte->phys_addr = KPTphys + (i << PAGE_SHIFT); } /* * 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 enabled? */ TUNABLE_INT_FETCH("vm.pmap.pg_ps_enabled", &pg_ps_enabled); 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_2mpage(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); } SYSCTL_NODE(_vm_pmap, OID_AUTO, pde, CTLFLAG_RD, 0, "2MB page mapping counters"); static u_long pmap_pde_demotions; SYSCTL_ULONG(_vm_pmap_pde, OID_AUTO, demotions, CTLFLAG_RD, &pmap_pde_demotions, 0, "2MB page demotions"); static u_long pmap_pde_mappings; SYSCTL_ULONG(_vm_pmap_pde, OID_AUTO, mappings, CTLFLAG_RD, &pmap_pde_mappings, 0, "2MB 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, "2MB page promotion failures"); static u_long pmap_pde_promotions; SYSCTL_ULONG(_vm_pmap_pde, OID_AUTO, promotions, CTLFLAG_RD, &pmap_pde_promotions, 0, "2MB page promotions"); SYSCTL_NODE(_vm_pmap, OID_AUTO, pdpe, CTLFLAG_RD, 0, "1GB page mapping counters"); static u_long pmap_pdpe_demotions; SYSCTL_ULONG(_vm_pmap_pdpe, OID_AUTO, demotions, CTLFLAG_RD, &pmap_pdpe_demotions, 0, "1GB page demotions"); /*************************************************** * Low level helper routines..... ***************************************************/ /* * Determine the appropriate bits to set in a PTE or PDE for a specified * caching mode. */ static 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); } /* * 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_action(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_update_pde_action, pmap_update_pde_teardown, &act); } else { pde_store(pde, newpde); if (CPU_ISSET(cpuid, &active)) pmap_update_pde_invalidate(va, newpde); } sched_unpin(); } #else /* !SMP */ /* * Normal, non-SMP, 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) { 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(); } } /* * Remove the specified set of pages from the data and instruction caches. * * In contrast to pmap_invalidate_cache_range(), this function does not * rely on the CPU's self-snoop feature, because it is intended for use * when moving pages into a different cache domain. */ void pmap_invalidate_cache_pages(vm_page_t *pages, int count) { vm_offset_t daddr, eva; int i; if (count >= PMAP_CLFLUSH_THRESHOLD / PAGE_SIZE || (cpu_feature & CPUID_CLFSH) == 0) pmap_invalidate_cache(); else { mfence(); for (i = 0; i < count; i++) { daddr = PHYS_TO_DMAP(VM_PAGE_TO_PHYS(pages[i])); eva = daddr + PAGE_SIZE; for (; daddr < eva; daddr += cpu_clflush_line_size) clflush(daddr); } mfence(); } } /* * Are we current address space or kernel? */ static __inline int pmap_is_current(pmap_t pmap) { return (pmap == kernel_pmap || (pmap->pm_pml4[PML4PML4I] & PG_FRAME) == (PML4pml4e[0] & PG_FRAME)); } /* * 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) { pdp_entry_t *pdpe; pd_entry_t *pde; pt_entry_t *pte; vm_paddr_t pa; pa = 0; PMAP_LOCK(pmap); pdpe = pmap_pdpe(pmap, va); if (pdpe != NULL && (*pdpe & PG_V) != 0) { if ((*pdpe & PG_PS) != 0) pa = (*pdpe & PG_PS_FRAME) | (va & PDPMASK); else { pde = pmap_pdpe_to_pde(pdpe, va); if ((*pde & PG_V) != 0) { if ((*pde & PG_PS) != 0) { pa = (*pde & PG_PS_FRAME) | (va & PDRMASK); } else { pte = pmap_pde_to_pte(pde, va); pa = (*pte & PG_FRAME) | (va & PAGE_MASK); } } } } PMAP_UNLOCK(pmap); return (pa); } /* * 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, *pdep; pt_entry_t pte; vm_paddr_t pa; vm_page_t m; pa = 0; m = NULL; PMAP_LOCK(pmap); retry: pdep = pmap_pde(pmap, va); if (pdep != NULL && (pde = *pdep)) { 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 { pte = *pmap_pde_to_pte(pdep, va); if ((pte & PG_V) && ((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); } vm_paddr_t pmap_kextract(vm_offset_t va) { pd_entry_t pde; vm_paddr_t pa; if (va >= DMAP_MIN_ADDRESS && va < DMAP_MAX_ADDRESS) { pa = DMAP_TO_PHYS(va); } else { pde = *vtopde(va); if (pde & PG_PS) { pa = (pde & PG_PS_FRAME) | (va & PDRMASK); } else { /* * Beware of a concurrent promotion that changes the * PDE at this point! For example, vtopte() must not * be used to access the PTE because it would use the * new PDE. It is, however, safe to use the old PDE * because the page table page is preserved by the * promotion. */ pa = *pmap_pde_to_pte(&pde, va); pa = (pa & PG_FRAME) | (va & PAGE_MASK); } } return (pa); } /*************************************************** * Low level mapping routines..... ***************************************************/ /* * Add a wired page to the kva. * Note: not SMP coherent. */ 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 | PG_G); } 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 | PG_G | pmap_cache_bits(mode, 0)); } /* * Remove a page from the kernel pagetables. * Note: not SMP coherent. */ 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) { return PHYS_TO_DMAP(start); } /* * 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 | PG_G | 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 = pmap_pde_pindex(va); 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) { root = vm_page_splay(mpte->pindex, pmap->pm_root); KASSERT(mpte == root, ("pmap_remove_pt_page: mpte %p is missing from pmap %p", mpte, pmap)); } 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_offset_t va, vm_page_t m, vm_page_t *free) { --m->wire_count; if (m->wire_count == 0) return (_pmap_unwire_pte_hold(pmap, va, m, free)); else return (0); } static int _pmap_unwire_pte_hold(pmap_t pmap, vm_offset_t va, vm_page_t m, vm_page_t *free) { PMAP_LOCK_ASSERT(pmap, MA_OWNED); /* * unmap the page table page */ if (m->pindex >= (NUPDE + NUPDPE)) { /* PDP page */ pml4_entry_t *pml4; pml4 = pmap_pml4e(pmap, va); *pml4 = 0; } else if (m->pindex >= NUPDE) { /* PD page */ pdp_entry_t *pdp; pdp = pmap_pdpe(pmap, va); *pdp = 0; } else { /* PTE page */ pd_entry_t *pd; pd = pmap_pde(pmap, va); *pd = 0; } pmap_resident_count_dec(pmap, 1); if (m->pindex < NUPDE) { /* We just released a PT, unhold the matching PD */ vm_page_t pdpg; pdpg = PHYS_TO_VM_PAGE(*pmap_pdpe(pmap, va) & PG_FRAME); pmap_unwire_pte_hold(pmap, va, pdpg, free); } if (m->pindex >= NUPDE && m->pindex < (NUPDE + NUPDPE)) { /* We just released a PD, unhold the matching PDP */ vm_page_t pdppg; pdppg = PHYS_TO_VM_PAGE(*pmap_pml4e(pmap, va) & PG_FRAME); pmap_unwire_pte_hold(pmap, va, pdppg, free); } /* * 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); /* * 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, pd_entry_t ptepde, vm_page_t *free) { vm_page_t mpte; if (va >= VM_MAXUSER_ADDRESS) return (0); KASSERT(ptepde != 0, ("pmap_unuse_pt: ptepde != 0")); mpte = PHYS_TO_VM_PAGE(ptepde & PG_FRAME); return (pmap_unwire_pte_hold(pmap, va, mpte, free)); } void pmap_pinit0(pmap_t pmap) { PMAP_LOCK_INIT(pmap); pmap->pm_pml4 = (pml4_entry_t *)PHYS_TO_DMAP(KPML4phys); 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 pml4pg; int i; PMAP_LOCK_INIT(pmap); /* * allocate the page directory page */ while ((pml4pg = vm_page_alloc(NULL, 0, VM_ALLOC_NORMAL | VM_ALLOC_NOOBJ | VM_ALLOC_WIRED | VM_ALLOC_ZERO)) == NULL) VM_WAIT; pmap->pm_pml4 = (pml4_entry_t *)PHYS_TO_DMAP(VM_PAGE_TO_PHYS(pml4pg)); if ((pml4pg->flags & PG_ZERO) == 0) pagezero(pmap->pm_pml4); /* Wire in kernel global address entries. */ pmap->pm_pml4[KPML4I] = KPDPphys | PG_RW | PG_V | PG_U; for (i = 0; i < NDMPML4E; i++) { pmap->pm_pml4[DMPML4I + i] = (DMPDPphys + (i << PAGE_SHIFT)) | PG_RW | PG_V | PG_U; } /* install self-referential address mapping entry(s) */ pmap->pm_pml4[PML4PML4I] = VM_PAGE_TO_PHYS(pml4pg) | PG_V | PG_RW | PG_A | PG_M; pmap->pm_root = NULL; 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. * * Note: If a page allocation fails at page table level two or three, * one or two pages may be held during the wait, only to be released * afterwards. This conservative approach is easily argued to avoid * race conditions. */ static vm_page_t _pmap_allocpte(pmap_t pmap, vm_pindex_t ptepindex, int flags) { vm_page_t m, pdppg, pdpg; 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")); PMAP_LOCK_ASSERT(pmap, MA_OWNED); /* * 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. */ if (ptepindex >= (NUPDE + NUPDPE)) { pml4_entry_t *pml4; vm_pindex_t pml4index; /* Wire up a new PDPE page */ pml4index = ptepindex - (NUPDE + NUPDPE); pml4 = &pmap->pm_pml4[pml4index]; *pml4 = VM_PAGE_TO_PHYS(m) | PG_U | PG_RW | PG_V | PG_A | PG_M; } else if (ptepindex >= NUPDE) { vm_pindex_t pml4index; vm_pindex_t pdpindex; pml4_entry_t *pml4; pdp_entry_t *pdp; /* Wire up a new PDE page */ pdpindex = ptepindex - NUPDE; pml4index = pdpindex >> NPML4EPGSHIFT; pml4 = &pmap->pm_pml4[pml4index]; if ((*pml4 & PG_V) == 0) { /* Have to allocate a new pdp, recurse */ if (_pmap_allocpte(pmap, NUPDE + NUPDPE + pml4index, flags) == NULL) { --m->wire_count; atomic_subtract_int(&cnt.v_wire_count, 1); vm_page_free_zero(m); return (NULL); } } else { /* Add reference to pdp page */ pdppg = PHYS_TO_VM_PAGE(*pml4 & PG_FRAME); pdppg->wire_count++; } pdp = (pdp_entry_t *)PHYS_TO_DMAP(*pml4 & PG_FRAME); /* Now find the pdp page */ pdp = &pdp[pdpindex & ((1ul << NPDPEPGSHIFT) - 1)]; *pdp = VM_PAGE_TO_PHYS(m) | PG_U | PG_RW | PG_V | PG_A | PG_M; } else { vm_pindex_t pml4index; vm_pindex_t pdpindex; pml4_entry_t *pml4; pdp_entry_t *pdp; pd_entry_t *pd; /* Wire up a new PTE page */ pdpindex = ptepindex >> NPDPEPGSHIFT; pml4index = pdpindex >> NPML4EPGSHIFT; /* First, find the pdp and check that its valid. */ pml4 = &pmap->pm_pml4[pml4index]; if ((*pml4 & PG_V) == 0) { /* Have to allocate a new pd, recurse */ if (_pmap_allocpte(pmap, NUPDE + pdpindex, flags) == NULL) { --m->wire_count; atomic_subtract_int(&cnt.v_wire_count, 1); vm_page_free_zero(m); return (NULL); } pdp = (pdp_entry_t *)PHYS_TO_DMAP(*pml4 & PG_FRAME); pdp = &pdp[pdpindex & ((1ul << NPDPEPGSHIFT) - 1)]; } else { pdp = (pdp_entry_t *)PHYS_TO_DMAP(*pml4 & PG_FRAME); pdp = &pdp[pdpindex & ((1ul << NPDPEPGSHIFT) - 1)]; if ((*pdp & PG_V) == 0) { /* Have to allocate a new pd, recurse */ if (_pmap_allocpte(pmap, NUPDE + pdpindex, flags) == NULL) { --m->wire_count; atomic_subtract_int(&cnt.v_wire_count, 1); vm_page_free_zero(m); return (NULL); } } else { /* Add reference to the pd page */ pdpg = PHYS_TO_VM_PAGE(*pdp & PG_FRAME); pdpg->wire_count++; } } pd = (pd_entry_t *)PHYS_TO_DMAP(*pdp & PG_FRAME); /* Now we know where the page directory page is */ pd = &pd[ptepindex & ((1ul << NPDEPGSHIFT) - 1)]; *pd = VM_PAGE_TO_PHYS(m) | PG_U | PG_RW | PG_V | PG_A | PG_M; } pmap_resident_count_inc(pmap, 1); return (m); } static vm_page_t pmap_allocpde(pmap_t pmap, vm_offset_t va, int flags) { vm_pindex_t pdpindex, ptepindex; pdp_entry_t *pdpe; vm_page_t pdpg; KASSERT((flags & (M_NOWAIT | M_WAITOK)) == M_NOWAIT || (flags & (M_NOWAIT | M_WAITOK)) == M_WAITOK, ("pmap_allocpde: flags is neither M_NOWAIT nor M_WAITOK")); retry: pdpe = pmap_pdpe(pmap, va); if (pdpe != NULL && (*pdpe & PG_V) != 0) { /* Add a reference to the pd page. */ pdpg = PHYS_TO_VM_PAGE(*pdpe & PG_FRAME); pdpg->wire_count++; } else { /* Allocate a pd page. */ ptepindex = pmap_pde_pindex(va); pdpindex = ptepindex >> NPDPEPGSHIFT; pdpg = _pmap_allocpte(pmap, NUPDE + pdpindex, flags); if (pdpg == NULL && (flags & M_WAITOK)) goto retry; } return (pdpg); } static vm_page_t pmap_allocpte(pmap_t pmap, vm_offset_t va, int flags) { vm_pindex_t ptepindex; pd_entry_t *pd; 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 = pmap_pde_pindex(va); retry: /* * Get the page directory entry */ pd = pmap_pde(pmap, va); /* * This supports switching from a 2MB page to a * normal 4K page. */ if (pd != NULL && (*pd & (PG_PS | PG_V)) == (PG_PS | PG_V)) { if (!pmap_demote_pde(pmap, pd, va)) { /* * Invalidation of the 2MB page mapping may have caused * the deallocation of the underlying PD page. */ pd = NULL; } } /* * If the page table page is mapped, we just increment the * hold count, and activate it. */ if (pd != NULL && (*pd & PG_V) != 0) { m = PHYS_TO_VM_PAGE(*pd & 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. ***************************************************/ /* * 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; 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)")); m = PHYS_TO_VM_PAGE(pmap->pm_pml4[PML4PML4I] & PG_FRAME); pmap->pm_pml4[KPML4I] = 0; /* KVA */ for (i = 0; i < NDMPML4E; i++) /* Direct Map */ pmap->pm_pml4[DMPML4I + i] = 0; pmap->pm_pml4[PML4PML4I] = 0; /* Recursive Mapping */ 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 - VM_MIN_KERNEL_ADDRESS; return sysctl_handle_long(oidp, &ksize, 0, req); } SYSCTL_PROC(_vm, OID_AUTO, kvm_size, CTLTYPE_LONG|CTLFLAG_RD, 0, 0, kvm_size, "LU", "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, "LU", "Amount of KVM free"); /* * grow the number of kernel page table entries, if needed */ void pmap_growkernel(vm_offset_t addr) { vm_paddr_t paddr; vm_page_t nkpg; pd_entry_t *pde, newpdir; pdp_entry_t *pdpe; mtx_assert(&kernel_map->system_mtx, MA_OWNED); /* * Return if "addr" is within the range of kernel page table pages * that were preallocated during pmap bootstrap. Moreover, leave * "kernel_vm_end" and the kernel page table as they were. * * The correctness of this action is based on the following * argument: vm_map_findspace() allocates contiguous ranges of the * kernel virtual address space. It calls this function if a range * ends after "kernel_vm_end". If the kernel is mapped between * "kernel_vm_end" and "addr", then the range cannot begin at * "kernel_vm_end". In fact, its beginning address cannot be less * than the kernel. Thus, there is no immediate need to allocate * any new kernel page table pages between "kernel_vm_end" and * "KERNBASE". */ if (KERNBASE < addr && addr <= KERNBASE + NKPT * NBPDR) return; addr = roundup2(addr, NBPDR); if (addr - 1 >= kernel_map->max_offset) addr = kernel_map->max_offset; while (kernel_vm_end < addr) { pdpe = pmap_pdpe(kernel_pmap, kernel_vm_end); if ((*pdpe & PG_V) == 0) { /* We need a new PDP entry */ nkpg = vm_page_alloc(NULL, kernel_vm_end >> PDPSHIFT, VM_ALLOC_INTERRUPT | VM_ALLOC_NOOBJ | VM_ALLOC_WIRED | VM_ALLOC_ZERO); if (nkpg == NULL) panic("pmap_growkernel: no memory to grow kernel"); if ((nkpg->flags & PG_ZERO) == 0) pmap_zero_page(nkpg); paddr = VM_PAGE_TO_PHYS(nkpg); *pdpe = (pdp_entry_t) (paddr | PG_V | PG_RW | PG_A | PG_M); continue; /* try again */ } pde = pmap_pdpe_to_pde(pdpe, kernel_vm_end); if ((*pde & PG_V) != 0) { 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, pmap_pde_pindex(kernel_vm_end), VM_ALLOC_INTERRUPT | VM_ALLOC_NOOBJ | VM_ALLOC_WIRED | VM_ALLOC_ZERO); if (nkpg == NULL) panic("pmap_growkernel: no memory to grow kernel"); if ((nkpg->flags & PG_ZERO) == 0) pmap_zero_page(nkpg); paddr = VM_PAGE_TO_PHYS(nkpg); newpdir = (pd_entry_t) (paddr | PG_V | PG_RW | PG_A | PG_M); pde_store(pde, 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 == 3); CTASSERT(_NPCPV == 168); 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 0xfffffffffffffffful #define PC_FREE1 0xfffffffffffffffful #define PC_FREE2 0x000000fffffffffful static const uint64_t pc_freemask[_NPCM] = { PC_FREE0, PC_FREE1, PC_FREE2 }; SYSCTL_LONG(_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. * * We do not, however, unmap 2mpages because subsequent accesses will * allocate per-page pv entries until repromotion occurs, thereby * exacerbating the shortage of free pv entries. */ 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; uint64_t inuse; int bit, field, freed; rw_assert(&pvh_global_lock, RA_WLOCKED); PMAP_LOCK_ASSERT(locked_pmap, MA_OWNED); pmap = NULL; free = m_pc = NULL; TAILQ_INIT(&newtail); while ((pc = TAILQ_FIRST(&pv_chunks)) != NULL && 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 = bsfq(inuse); pv = &pc->pc_pventry[field * 64 + bit]; va = pv->pv_va; pde = pmap_pde(pmap, va); if ((*pde & PG_PS) != 0) continue; pte = pmap_pde_to_pte(pde, 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, *pde, &free); freed++; } } if (freed == 0) { TAILQ_INSERT_TAIL(&newtail, pc, pc_lru); continue; } /* Every freed mapping is for a 4 KB page. */ pmap_resident_count_dec(pmap, 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); if (pc->pc_map[0] == PC_FREE0 && pc->pc_map[1] == PC_FREE1 && pc->pc_map[2] == PC_FREE2) { 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(DMAP_TO_PHYS((vm_offset_t)pc)); dump_drop_page(m_pc->phys_addr); break; } 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) break; } 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 && 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 / 64; bit = idx % 64; pc->pc_map[field] |= 1ul << bit; if (pc->pc_map[0] != PC_FREE0 || pc->pc_map[1] != PC_FREE1 || pc->pc_map[2] != PC_FREE2) { /* 98% of the time, pc is already at the head of the list. */ if (__predict_false(pc != TAILQ_FIRST(&pmap->pm_pvchunk))) { 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(DMAP_TO_PHYS((vm_offset_t)pc)); dump_drop_page(m->phys_addr); vm_page_unwire(m, 0); vm_page_free(m); } /* * 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) { 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++); retry: pc = TAILQ_FIRST(&pmap->pm_pvchunk); if (pc != NULL) { for (field = 0; field < _NPCM; field++) { if (pc->pc_map[field]) { bit = bsfq(pc->pc_map[field]); break; } } if (field < _NPCM) { pv = &pc->pc_pventry[field * 64 + bit]; pc->pc_map[field] &= ~(1ul << bit); /* If this was the last item, move it to tail */ if (pc->pc_map[0] == 0 && pc->pc_map[1] == 0 && pc->pc_map[2] == 0) { TAILQ_REMOVE(&pmap->pm_pvchunk, pc, pc_list); TAILQ_INSERT_TAIL(&pmap->pm_pvchunk, pc, pc_list); } pv_entry_count++; PV_STAT(pv_entry_spare--); return (pv); } } /* No free items, allocate another chunk */ m = vm_page_alloc(NULL, 0, VM_ALLOC_NORMAL | VM_ALLOC_NOOBJ | VM_ALLOC_WIRED); if (m == NULL) { if (try) { 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++); dump_add_page(m->phys_addr); pc = (void *)PHYS_TO_DMAP(m->phys_addr); pc->pc_pmap = pmap; pc->pc_map[0] = PC_FREE0 & ~1ul; /* preallocated bit 0 */ pc->pc_map[1] = PC_FREE1; pc->pc_map[2] = PC_FREE2; TAILQ_INSERT_TAIL(&pv_chunks, pc, pc_lru); pv = &pc->pc_pventry[0]; TAILQ_INSERT_HEAD(&pmap->pm_pvchunk, pc, pc_list); pv_entry_count++; PV_STAT(pv_entry_spare += _NPCPV - 1); return (pv); } /* * First find and then remove the pv entry for the specified pmap and virtual * address from the specified pv list. Returns the pv entry if found and NULL * otherwise. This operation can be performed on pv lists for either 4KB or * 2MB page mappings. */ 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); } /* * After demotion from a 2MB page mapping to 512 4KB page mappings, * destroy the pv entry for the 2MB page mapping and reinstantiate the pv * entries for each of the 4KB page mappings. */ 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 2mpage aligned")); /* * Transfer the 2mpage's pv entry for this mapping to the first * page's pv list. */ pvh = pa_to_pvh(pa); va = trunc_2mpage(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); } /* * After promotion from 512 4KB page mappings to a single 2MB page mapping, * replace the many pv entries for the 4KB page mappings by a single pv entry * for the 2MB page mapping. */ 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 2mpage aligned")); /* * Transfer the first page's pv entry for this mapping to the * 2mpage'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_2mpage(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); } /* * First find and then destroy the pv entry for the specified pmap and virtual * address. This operation can be performed on pv lists for either 4KB or 2MB * page mappings. */ 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 = 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 entry for a 2MB page mapping. */ 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 = 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 2MB page mapping. If demotion fails, the 2MB 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 2MB page mapping and return "failure" if the * mapping was never accessed or the allocation of the new * page table page fails. If the 2MB page mapping belongs to * the direct map region of the kernel's address space, then * the page allocation request specifies the highest possible * priority (VM_ALLOC_INTERRUPT). Otherwise, the priority is * normal. Page table pages are preallocated for every other * part of the kernel address space, so the direct map region * is the only part of the kernel address space that must be * handled here. */ if ((oldpde & PG_A) == 0 || (mpte = vm_page_alloc(NULL, pmap_pde_pindex(va), (va >= DMAP_MIN_ADDRESS && va < DMAP_MAX_ADDRESS ? VM_ALLOC_INTERRUPT : VM_ALLOC_NORMAL) | VM_ALLOC_NOOBJ | VM_ALLOC_WIRED)) == NULL) { free = NULL; pmap_remove_pde(pmap, pde, trunc_2mpage(va), &free); pmap_invalidate_page(pmap, trunc_2mpage(va)); pmap_free_zero_pages(free); CTR2(KTR_PMAP, "pmap_demote_pde: failure for va %#lx" " in pmap %p", va, pmap); return (FALSE); } if (va < VM_MAXUSER_ADDRESS) pmap_resident_count_inc(pmap, 1); } mptepa = VM_PAGE_TO_PHYS(mpte); firstpte = (pt_entry_t *)PHYS_TO_DMAP(mptepa); 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 pde_store(pde, newpde); /* * Invalidate a stale recursive mapping of the page table page. */ if (va >= VM_MAXUSER_ADDRESS) 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 %#lx" " in pmap %p", va, pmap); return (TRUE); } /* * pmap_remove_pde: do the things to unmap a superpage in a process */ static int 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 2mpage 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_resident_count_dec(pmap, 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_resident_count_dec(pmap, 1); 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); } } return (pmap_unuse_pt(pmap, sva, *pmap_pdpe(pmap, sva), free)); } /* * 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, pd_entry_t ptepde, vm_page_t *free) { pt_entry_t oldpte; vm_page_t m; PMAP_LOCK_ASSERT(pmap, MA_OWNED); oldpte = pte_load_clear(ptq); if (oldpte & PG_W) pmap->pm_stats.wired_count -= 1; pmap_resident_count_dec(pmap, 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, ptepde, free)); } /* * Remove a single page from a process address space */ static void pmap_remove_page(pmap_t pmap, vm_offset_t va, pd_entry_t *pde, vm_page_t *free) { pt_entry_t *pte; PMAP_LOCK_ASSERT(pmap, MA_OWNED); if ((*pde & PG_V) == 0) return; pte = pmap_pde_to_pte(pde, va); if ((*pte & PG_V) == 0) return; pmap_remove_pte(pmap, pte, va, *pde, 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 va, va_next; pml4_entry_t *pml4e; pdp_entry_t *pdpe; pd_entry_t ptpaddr, *pde; 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); 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) { pde = pmap_pde(pmap, sva); if (pde && (*pde & PG_PS) == 0) { pmap_remove_page(pmap, sva, pde, &free); goto out; } } for (; sva < eva; sva = va_next) { if (pmap->pm_stats.resident_count == 0) break; pml4e = pmap_pml4e(pmap, sva); if ((*pml4e & PG_V) == 0) { va_next = (sva + NBPML4) & ~PML4MASK; if (va_next < sva) va_next = eva; continue; } pdpe = pmap_pml4e_to_pdpe(pml4e, sva); if ((*pdpe & PG_V) == 0) { va_next = (sva + NBPDP) & ~PDPMASK; if (va_next < sva) va_next = eva; continue; } /* * Calculate index for next page table. */ va_next = (sva + NBPDR) & ~PDRMASK; if (va_next < sva) va_next = eva; pde = pmap_pdpe_to_pde(pdpe, sva); ptpaddr = *pde; /* * Weed out invalid mappings. */ 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 == va_next && eva >= va_next) { /* * 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, pde, sva, &free); continue; } else if (!pmap_demote_pde(pmap, pde, sva)) { /* The large page mapping was destroyed. */ continue; } else ptpaddr = *pde; } /* * 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 (va_next > eva) va_next = eva; va = va_next; for (pte = pmap_pde_to_pte(pde, sva); sva != va_next; pte++, sva += PAGE_SIZE) { if (*pte == 0) { if (va != va_next) { pmap_invalidate_range(pmap, va, sva); va = va_next; } continue; } if ((*pte & PG_G) == 0) anyvalid = 1; else if (va == va_next) va = sva; if (pmap_remove_pte(pmap, pte, sva, ptpaddr, &free)) { sva += PAGE_SIZE; break; } } if (va != va_next) pmap_invalidate_range(pmap, va, sva); } out: 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); 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) { pmap = PV_PMAP(pv); PMAP_LOCK(pmap); va = pv->pv_va; 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_resident_count_dec(pmap, 1); pde = pmap_pde(pmap, pv->pv_va); KASSERT((*pde & PG_PS) == 0, ("pmap_remove_all: found" " a 2mpage in page %p's pv list", m)); pte = pmap_pde_to_pte(pde, 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, *pde, &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); rw_wunlock(&pvh_global_lock); pmap_free_zero_pages(free); } /* * pmap_protect_pde: do the things to protect a 2mpage 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 2mpage 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); if ((prot & VM_PROT_EXECUTE) == 0) newpde |= pg_nx; if (newpde != oldpde) { if (!atomic_cmpset_long(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 va_next; pml4_entry_t *pml4e; pdp_entry_t *pdpe; pd_entry_t ptpaddr, *pde; pt_entry_t *pte; int anychanged; boolean_t pv_lists_locked; if ((prot & VM_PROT_READ) == VM_PROT_NONE) { pmap_remove(pmap, sva, eva); return; } if ((prot & (VM_PROT_WRITE|VM_PROT_EXECUTE)) == (VM_PROT_WRITE|VM_PROT_EXECUTE)) return; pv_lists_locked = FALSE; resume: anychanged = 0; PMAP_LOCK(pmap); for (; sva < eva; sva = va_next) { pml4e = pmap_pml4e(pmap, sva); if ((*pml4e & PG_V) == 0) { va_next = (sva + NBPML4) & ~PML4MASK; if (va_next < sva) va_next = eva; continue; } pdpe = pmap_pml4e_to_pdpe(pml4e, sva); if ((*pdpe & PG_V) == 0) { va_next = (sva + NBPDP) & ~PDPMASK; if (va_next < sva) va_next = eva; continue; } va_next = (sva + NBPDR) & ~PDRMASK; if (va_next < sva) va_next = eva; pde = pmap_pdpe_to_pde(pdpe, sva); ptpaddr = *pde; /* * Weed out invalid mappings. */ 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 == va_next && eva >= va_next) { /* * The TLB entry for a PG_G mapping is * invalidated by pmap_protect_pde(). */ if (pmap_protect_pde(pmap, pde, sva, prot)) anychanged = 1; 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); rw_wlock(&pvh_global_lock); goto resume; } } if (!pmap_demote_pde(pmap, pde, sva)) { /* * The large page mapping was * destroyed. */ continue; } } } if (va_next > eva) va_next = eva; for (pte = pmap_pde_to_pte(pde, sva); sva != va_next; pte++, sva += PAGE_SIZE) { pt_entry_t obits, pbits; vm_page_t m; retry: 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); } if ((prot & VM_PROT_EXECUTE) == 0) pbits |= pg_nx; if (pbits != obits) { if (!atomic_cmpset_long(pte, obits, pbits)) goto retry; if (obits & PG_G) pmap_invalidate_page(pmap, sva); else anychanged = 1; } } } if (anychanged) pmap_invalidate_all(pmap); if (pv_lists_locked) rw_wunlock(&pvh_global_lock); PMAP_UNLOCK(pmap); } /* * Tries to promote the 512, contiguous 4KB page mappings that are within a * single page table page (PTP) to a single 2MB 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. */ 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 2MB page. */ firstpte = (pt_entry_t *)PHYS_TO_DMAP(*pde & PG_FRAME); 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 %#lx" " 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_long(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 %#lx" " 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_long(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 %#lx" " 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 %#lx" " 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 == pmap_pde_pindex(va), ("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 pde_store(pde, PG_PS | newpde); pmap_pde_promotions++; CTR2(KTR_PMAP, "pmap_promote_pde: success for va %#lx" " 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%lx)", 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); /* * 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 != NULL && (*pde & PG_V) != 0) { if ((*pde & PG_PS) != 0) panic("pmap_enter: attempted pmap_enter on 2MB page"); pte = pmap_pde_to_pte(pde, va); } else panic("pmap_enter: invalid page directory va=%#lx", 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%lx", va)); } } else pmap_resident_count_inc(pmap, 1); /* * 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); } if ((prot & VM_PROT_EXECUTE) == 0) newpte |= pg_nx; if (wired) newpte |= PG_W; if (va < VM_MAXUSER_ADDRESS) newpte |= PG_U; if (pmap == kernel_pmap) newpte |= PG_G; /* * 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) || ((origpte & PG_NX) == 0 && (newpte & PG_NX))) invlva = TRUE; } if ((origpte & (PG_M | PG_RW)) == (PG_M | PG_RW)) { if ((origpte & PG_MANAGED) != 0) vm_page_dirty(om); if ((newpte & PG_RW) == 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); rw_wunlock(&pvh_global_lock); PMAP_UNLOCK(pmap); } /* * Tries to create a 2MB 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; vm_page_t free, mpde; rw_assert(&pvh_global_lock, RA_WLOCKED); PMAP_LOCK_ASSERT(pmap, MA_OWNED); if ((mpde = pmap_allocpde(pmap, va, M_NOWAIT)) == NULL) { CTR2(KTR_PMAP, "pmap_enter_pde: failure for va %#lx" " in pmap %p", va, pmap); return (FALSE); } pde = (pd_entry_t *)PHYS_TO_DMAP(VM_PAGE_TO_PHYS(mpde)); pde = &pde[pmap_pde_index(va)]; if ((*pde & PG_V) != 0) { KASSERT(mpde->wire_count > 1, ("pmap_enter_pde: mpde's wire count is too low")); mpde->wire_count--; 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))) { free = NULL; if (pmap_unwire_pte_hold(pmap, va, mpde, &free)) { pmap_invalidate_page(pmap, va); pmap_free_zero_pages(free); } CTR2(KTR_PMAP, "pmap_enter_pde: failure for va %#lx" " in pmap %p", va, pmap); return (FALSE); } } if ((prot & VM_PROT_EXECUTE) == 0) newpde |= pg_nx; if (va < VM_MAXUSER_ADDRESS) newpde |= PG_U; /* * Increment counters. */ pmap_resident_count_inc(pmap, 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) { vm_page_t free; pt_entry_t *pte; vm_paddr_t pa; 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) { vm_pindex_t ptepindex; pd_entry_t *ptepa; /* * Calculate pagetable page index */ ptepindex = pmap_pde_pindex(va); if (mpte && (mpte->pindex == ptepindex)) { mpte->wire_count++; } else { /* * Get the page directory entry */ ptepa = pmap_pde(pmap, va); /* * If the page table page is mapped, we just increment * the hold count, and activate it. */ if (ptepa && (*ptepa & PG_V) != 0) { 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); } } pte = (pt_entry_t *)PHYS_TO_DMAP(VM_PAGE_TO_PHYS(mpte)); pte = &pte[pmap_pte_index(va)]; } else { mpte = NULL; 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, va, mpte, &free)) { pmap_invalidate_page(pmap, va); pmap_free_zero_pages(free); } mpte = NULL; } return (mpte); } /* * Increment counters */ pmap_resident_count_inc(pmap, 1); pa = VM_PAGE_TO_PHYS(m) | pmap_cache_bits(m->md.pat_mode, 0); if ((prot & VM_PROT_EXECUTE) == 0) pa |= pg_nx; /* * 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, pdpg; 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 ((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 2MB 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 2MB pages. Since "ptepa" is 2M aligned and * "size" is a multiple of 2M, 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) { pdpg = pmap_allocpde(pmap, addr, M_NOWAIT); if (pdpg == NULL) { /* * The creation of mappings below is only an * optimization. If a page directory page * cannot be allocated without blocking, * continue on to the next mapping rather than * blocking. */ addr += NBPDR; continue; } pde = (pd_entry_t *)PHYS_TO_DMAP(VM_PAGE_TO_PHYS(pdpg)); pde = &pde[pmap_pde_index(addr)]; if ((*pde & PG_V) == 0) { pde_store(pde, pa | PG_PS | PG_M | PG_A | PG_U | PG_RW | PG_V); pmap_resident_count_inc(pmap, NBPDR / PAGE_SIZE); pmap_pde_mappings++; } else { /* Continue on if the PDE is already valid. */ pdpg->wire_count--; KASSERT(pdpg->wire_count > 0, ("pmap_object_init_pt: missing reference " "to page directory page, va: 0x%lx", addr)); } 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; /* * Wiring is not a hardware characteristic so there is no need to * invalidate TLB. */ 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_pde_to_pte(pde, va); if (wired && (*pte & PG_W) == 0) { pmap->pm_stats.wired_count++; atomic_set_long(pte, PG_W); } else if (!wired && (*pte & PG_W) != 0) { pmap->pm_stats.wired_count--; atomic_clear_long(pte, PG_W); } 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 va_next; if (dst_addr != src_addr) 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); } for (addr = src_addr; addr < end_addr; addr = va_next) { pt_entry_t *src_pte, *dst_pte; vm_page_t dstmpde, dstmpte, srcmpte; pml4_entry_t *pml4e; pdp_entry_t *pdpe; pd_entry_t srcptepaddr, *pde; KASSERT(addr < UPT_MIN_ADDRESS, ("pmap_copy: invalid to pmap_copy page tables")); pml4e = pmap_pml4e(src_pmap, addr); if ((*pml4e & PG_V) == 0) { va_next = (addr + NBPML4) & ~PML4MASK; if (va_next < addr) va_next = end_addr; continue; } pdpe = pmap_pml4e_to_pdpe(pml4e, addr); if ((*pdpe & PG_V) == 0) { va_next = (addr + NBPDP) & ~PDPMASK; if (va_next < addr) va_next = end_addr; continue; } va_next = (addr + NBPDR) & ~PDRMASK; if (va_next < addr) va_next = end_addr; pde = pmap_pdpe_to_pde(pdpe, addr); srcptepaddr = *pde; if (srcptepaddr == 0) continue; if (srcptepaddr & PG_PS) { dstmpde = pmap_allocpde(dst_pmap, addr, M_NOWAIT); if (dstmpde == NULL) break; pde = (pd_entry_t *) PHYS_TO_DMAP(VM_PAGE_TO_PHYS(dstmpde)); pde = &pde[pmap_pde_index(addr)]; if (*pde == 0 && ((srcptepaddr & PG_MANAGED) == 0 || pmap_pv_insert_pde(dst_pmap, addr, srcptepaddr & PG_PS_FRAME))) { *pde = srcptepaddr & ~PG_W; pmap_resident_count_inc(dst_pmap, NBPDR / PAGE_SIZE); } else dstmpde->wire_count--; continue; } srcptepaddr &= PG_FRAME; srcmpte = PHYS_TO_VM_PAGE(srcptepaddr); KASSERT(srcmpte->wire_count > 0, ("pmap_copy: source page table page is unused")); if (va_next > end_addr) va_next = end_addr; src_pte = (pt_entry_t *)PHYS_TO_DMAP(srcptepaddr); src_pte = &src_pte[pmap_pte_index(addr)]; dstmpte = NULL; while (addr < va_next) { pt_entry_t ptetemp; ptetemp = *src_pte; /* * we only virtual copy managed pages */ if ((ptetemp & PG_MANAGED) != 0) { if (dstmpte != NULL && dstmpte->pindex == pmap_pde_pindex(addr)) dstmpte->wire_count++; else if ((dstmpte = pmap_allocpte(dst_pmap, addr, M_NOWAIT)) == NULL) goto out; dst_pte = (pt_entry_t *) PHYS_TO_DMAP(VM_PAGE_TO_PHYS(dstmpte)); dst_pte = &dst_pte[pmap_pte_index(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); pmap_resident_count_inc(dst_pmap, 1); } else { free = NULL; if (pmap_unwire_pte_hold(dst_pmap, addr, 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: rw_wunlock(&pvh_global_lock); PMAP_UNLOCK(src_pmap); PMAP_UNLOCK(dst_pmap); } /* * 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) { vm_offset_t va = PHYS_TO_DMAP(VM_PAGE_TO_PHYS(m)); pagezero((void *)va); } /* * 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) { vm_offset_t va = PHYS_TO_DMAP(VM_PAGE_TO_PHYS(m)); if (off == 0 && size == PAGE_SIZE) pagezero((void *)va); else bzero((char *)va + off, size); } /* * 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) { vm_offset_t va = PHYS_TO_DMAP(VM_PAGE_TO_PHYS(m)); pagezero((void *)va); } /* * 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 msrc, vm_page_t mdst) { vm_offset_t src = PHYS_TO_DMAP(VM_PAGE_TO_PHYS(msrc)); vm_offset_t dst = PHYS_TO_DMAP(VM_PAGE_TO_PHYS(mdst)); pagecopy((void *)src, (void *)dst); } /* * 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); TAILQ_FOREACH(pv, &pvh->pv_list, pv_list) { pmap = PV_PMAP(pv); PMAP_LOCK(pmap); pte = pmap_pte(pmap, pv->pv_va); if ((*pte & PG_W) != 0) count++; PMAP_UNLOCK(pmap); } return (count); } /* * Returns TRUE if the given page is mapped individually or as part of * a 2mpage. 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) { pd_entry_t ptepde; 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; int64_t bit; uint64_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); 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 = bsfq(inuse); bitmask = 1UL << bit; idx = field * 64 + bit; pv = &pc->pc_pventry[idx]; inuse &= ~bitmask; pte = pmap_pdpe(pmap, pv->pv_va); ptepde = *pte; pte = pmap_pdpe_to_pde(pte, pv->pv_va); tpte = *pte; if ((tpte & (PG_PS | PG_V)) == PG_V) { ptepde = tpte; pte = (pt_entry_t *)PHYS_TO_DMAP(tpte & PG_FRAME); pte = &pte[pmap_pte_index(pv->pv_va)]; tpte = *pte & ~PG_PTE_PAT; } if ((tpte & PG_V) == 0) 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_resident_count_dec(pmap, 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 ((mt->aflags & PGA_WRITEABLE) != 0 && 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_resident_count_dec(pmap, 1); 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_resident_count_dec(pmap, 1); TAILQ_REMOVE(&m->md.pv_list, pv, pv_list); if ((m->aflags & PGA_WRITEABLE) != 0 && 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, ptepde, &free); } } if (allfree) { TAILQ_REMOVE(&pmap->pm_pvchunk, pc, pc_list); free_pv_chunk(pc); } } 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; TAILQ_FOREACH(pv, &pvh->pv_list, pv_list) { pmap = PV_PMAP(pv); PMAP_LOCK(pmap); pte = pmap_pte(pmap, pv->pv_va); rv = (*pte & (PG_M | PG_RW)) == (PG_M | PG_RW); PMAP_UNLOCK(pmap); if (rv) break; } 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 != NULL && (*pde & (PG_PS | PG_V)) == PG_V) { pte = pmap_pde_to_pte(pde, addr); rv = (*pte & PG_V) == 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 2mpage 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; TAILQ_FOREACH(pv, &pvh->pv_list, pv_list) { pmap = PV_PMAP(pv); PMAP_LOCK(pmap); pte = pmap_pte(pmap, pv->pv_va); rv = (*pte & (PG_A | PG_V)) == (PG_A | PG_V); PMAP_UNLOCK(pmap); if (rv) break; } 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; pmap_t pmap; pv_entry_t next_pv, pv; 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); 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) { pmap = PV_PMAP(pv); PMAP_LOCK(pmap); va = pv->pv_va; 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_remove_write: found a 2mpage in page %p's pv list", m)); pte = pmap_pde_to_pte(pde, pv->pv_va); retry: oldpte = *pte; if (oldpte & PG_RW) { if (!atomic_cmpset_long(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); 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)); rw_wlock(&pvh_global_lock); 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, pvn) { pmap = PV_PMAP(pv); PMAP_LOCK(pmap); va = pv->pv_va; 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, pde, 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 2mpage in page %p's pv list", m)); pte = pmap_pde_to_pte(pde, pv->pv_va); if ((*pte & PG_A) != 0) { atomic_clear_long(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: 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; pmap_t pmap; pv_entry_t next_pv, pv; 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); 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) { pmap = PV_PMAP(pv); PMAP_LOCK(pmap); va = pv->pv_va; 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_pde_to_pte(pde, va); oldpte = *pte; if ((oldpte & PG_V) != 0) { while (!atomic_cmpset_long(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 2mpage in page %p's pv list", m)); pte = pmap_pde_to_pte(pde, pv->pv_va); if ((*pte & (PG_M | PG_RW)) == (PG_M | PG_RW)) { atomic_clear_long(pte, PG_M); pmap_invalidate_page(pmap, pv->pv_va); } PMAP_UNLOCK(pmap); } 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; pmap_t pmap; pv_entry_t next_pv, pv; 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); 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) { pmap = PV_PMAP(pv); PMAP_LOCK(pmap); va = pv->pv_va; 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, pde, 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 2mpage in page %p's pv list", m)); pte = pmap_pde_to_pte(pde, pv->pv_va); if (*pte & PG_A) { atomic_clear_long(pte, PG_A); pmap_invalidate_page(pmap, pv->pv_va); } PMAP_UNLOCK(pmap); } 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 2MB 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; /* * If the specified range of physical addresses fits within the direct * map window, use the direct map. */ if (pa < dmaplimit && pa + size < dmaplimit) { va = PHYS_TO_DMAP(pa); if (!pmap_change_attr(va, size, mode)) return ((void *)va); } offset = pa & PAGE_MASK; size = roundup(offset + size, PAGE_SIZE); va = kmem_alloc_nofault(kernel_map, size); if (!va) panic("pmap_mapdev: Couldn't alloc kernel virtual memory"); pa = trunc_page(pa); 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 + tmpsize); 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 we gave a direct map region in pmap_mapdev, do nothing */ if (va >= DMAP_MIN_ADDRESS && va < DMAP_MAX_ADDRESS) 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); } /* * Tries to demote a 1GB page mapping. */ static boolean_t pmap_demote_pdpe(pmap_t pmap, pdp_entry_t *pdpe, vm_offset_t va) { pdp_entry_t newpdpe, oldpdpe; pd_entry_t *firstpde, newpde, *pde; vm_paddr_t mpdepa; vm_page_t mpde; PMAP_LOCK_ASSERT(pmap, MA_OWNED); oldpdpe = *pdpe; KASSERT((oldpdpe & (PG_PS | PG_V)) == (PG_PS | PG_V), ("pmap_demote_pdpe: oldpdpe is missing PG_PS and/or PG_V")); if ((mpde = vm_page_alloc(NULL, va >> PDPSHIFT, VM_ALLOC_INTERRUPT | VM_ALLOC_NOOBJ | VM_ALLOC_WIRED)) == NULL) { CTR2(KTR_PMAP, "pmap_demote_pdpe: failure for va %#lx" " in pmap %p", va, pmap); return (FALSE); } mpdepa = VM_PAGE_TO_PHYS(mpde); firstpde = (pd_entry_t *)PHYS_TO_DMAP(mpdepa); newpdpe = mpdepa | PG_M | PG_A | (oldpdpe & PG_U) | PG_RW | PG_V; KASSERT((oldpdpe & PG_A) != 0, ("pmap_demote_pdpe: oldpdpe is missing PG_A")); KASSERT((oldpdpe & (PG_M | PG_RW)) != PG_RW, ("pmap_demote_pdpe: oldpdpe is missing PG_M")); newpde = oldpdpe; /* * Initialize the page directory page. */ for (pde = firstpde; pde < firstpde + NPDEPG; pde++) { *pde = newpde; newpde += NBPDR; } /* * Demote the mapping. */ *pdpe = newpdpe; /* * Invalidate a stale recursive mapping of the page directory page. */ pmap_invalidate_page(pmap, (vm_offset_t)vtopde(va)); pmap_pdpe_demotions++; CTR2(KTR_PMAP, "pmap_demote_pdpe: success for va %#lx" " in pmap %p", va, pmap); return (TRUE); } /* * 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" is a normal page, update its direct mapping. This update * can be relied upon to perform any cache operations that are * required for data coherence. */ if ((m->flags & PG_FICTITIOUS) == 0 && pmap_change_attr(PHYS_TO_DMAP(VM_PAGE_TO_PHYS(m)), PAGE_SIZE, m->md.pat_mode)) panic("memory attribute change on the direct map failed"); } /* * 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 direct map or the kernel map. If * the virtual address range is contained within the kernel map, then the * memory type for each of the corresponding ranges of the direct map is also * changed. (The corresponding ranges of the direct map are those ranges that * map the same physical pages as the specified virtual address range.) These * changes to the direct map are necessary because Intel describes the * behavior of their processors as "undefined" if two or more mappings to the * same physical page have different memory types. * * 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. In the * latter case, the memory type may have been changed on some part of the * virtual address range or the direct map. */ int pmap_change_attr(vm_offset_t va, vm_size_t size, int mode) { int error; PMAP_LOCK(kernel_pmap); error = pmap_change_attr_locked(va, size, mode); PMAP_UNLOCK(kernel_pmap); return (error); } static int pmap_change_attr_locked(vm_offset_t va, vm_size_t size, int mode) { vm_offset_t base, offset, tmpva; vm_paddr_t pa_start, pa_end; pdp_entry_t *pdpe; pd_entry_t *pde; pt_entry_t *pte; int cache_bits_pte, cache_bits_pde, error; boolean_t changed; PMAP_LOCK_ASSERT(kernel_pmap, MA_OWNED); base = trunc_page(va); offset = va & PAGE_MASK; size = roundup(offset + size, PAGE_SIZE); /* * Only supported on kernel virtual addresses, including the direct * map but excluding the recursive map. */ if (base < DMAP_MIN_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 2MB pages * into 4KB pages if required. */ for (tmpva = base; tmpva < base + size; ) { pdpe = pmap_pdpe(kernel_pmap, tmpva); if (*pdpe == 0) return (EINVAL); if (*pdpe & PG_PS) { /* * If the current 1GB page already has the required * memory type, then we need not demote this page. Just * increment tmpva to the next 1GB page frame. */ if ((*pdpe & PG_PDE_CACHE) == cache_bits_pde) { tmpva = trunc_1gpage(tmpva) + NBPDP; continue; } /* * If the current offset aligns with a 1GB page frame * and there is at least 1GB left within the range, then * we need not break down this page into 2MB pages. */ if ((tmpva & PDPMASK) == 0 && tmpva + PDPMASK < base + size) { tmpva += NBPDP; continue; } if (!pmap_demote_pdpe(kernel_pmap, pdpe, tmpva)) return (ENOMEM); } pde = pmap_pdpe_to_pde(pdpe, tmpva); if (*pde == 0) return (EINVAL); if (*pde & PG_PS) { /* * If the current 2MB page already has the required * memory type, then we need not demote this page. Just * increment tmpva to the next 2MB page frame. */ if ((*pde & PG_PDE_CACHE) == cache_bits_pde) { tmpva = trunc_2mpage(tmpva) + NBPDR; continue; } /* * If the current offset aligns with a 2MB page frame * and there is at least 2MB 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)) return (ENOMEM); } pte = pmap_pde_to_pte(pde, tmpva); if (*pte == 0) return (EINVAL); tmpva += PAGE_SIZE; } error = 0; /* * Ok, all the pages exist, so run through them updating their * cache mode if required. */ pa_start = pa_end = 0; for (tmpva = base; tmpva < base + size; ) { pdpe = pmap_pdpe(kernel_pmap, tmpva); if (*pdpe & PG_PS) { if ((*pdpe & PG_PDE_CACHE) != cache_bits_pde) { pmap_pde_attr(pdpe, cache_bits_pde); changed = TRUE; } if (tmpva >= VM_MIN_KERNEL_ADDRESS) { if (pa_start == pa_end) { /* Start physical address run. */ pa_start = *pdpe & PG_PS_FRAME; pa_end = pa_start + NBPDP; } else if (pa_end == (*pdpe & PG_PS_FRAME)) pa_end += NBPDP; else { /* Run ended, update direct map. */ error = pmap_change_attr_locked( PHYS_TO_DMAP(pa_start), pa_end - pa_start, mode); if (error != 0) break; /* Start physical address run. */ pa_start = *pdpe & PG_PS_FRAME; pa_end = pa_start + NBPDP; } } tmpva = trunc_1gpage(tmpva) + NBPDP; continue; } pde = pmap_pdpe_to_pde(pdpe, tmpva); if (*pde & PG_PS) { if ((*pde & PG_PDE_CACHE) != cache_bits_pde) { pmap_pde_attr(pde, cache_bits_pde); changed = TRUE; } if (tmpva >= VM_MIN_KERNEL_ADDRESS) { if (pa_start == pa_end) { /* Start physical address run. */ pa_start = *pde & PG_PS_FRAME; pa_end = pa_start + NBPDR; } else if (pa_end == (*pde & PG_PS_FRAME)) pa_end += NBPDR; else { /* Run ended, update direct map. */ error = pmap_change_attr_locked( PHYS_TO_DMAP(pa_start), pa_end - pa_start, mode); if (error != 0) break; /* Start physical address run. */ pa_start = *pde & PG_PS_FRAME; pa_end = pa_start + NBPDR; } } tmpva = trunc_2mpage(tmpva) + NBPDR; } else { pte = pmap_pde_to_pte(pde, tmpva); if ((*pte & PG_PTE_CACHE) != cache_bits_pte) { pmap_pte_attr(pte, cache_bits_pte); changed = TRUE; } if (tmpva >= VM_MIN_KERNEL_ADDRESS) { if (pa_start == pa_end) { /* Start physical address run. */ pa_start = *pte & PG_FRAME; pa_end = pa_start + PAGE_SIZE; } else if (pa_end == (*pte & PG_FRAME)) pa_end += PAGE_SIZE; else { /* Run ended, update direct map. */ error = pmap_change_attr_locked( PHYS_TO_DMAP(pa_start), pa_end - pa_start, mode); if (error != 0) break; /* Start physical address run. */ pa_start = *pte & PG_FRAME; pa_end = pa_start + PAGE_SIZE; } } tmpva += PAGE_SIZE; } } if (error == 0 && pa_start != pa_end) error = pmap_change_attr_locked(PHYS_TO_DMAP(pa_start), pa_end - pa_start, mode); /* * Flush CPU caches if required 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 (error); } /* * Demotes any mapping within the direct map region that covers more than the * specified range of physical addresses. This range's size must be a power * of two and its starting address must be a multiple of its size. Since the * demotion does not change any attributes of the mapping, a TLB invalidation * is not mandatory. The caller may, however, request a TLB invalidation. */ void pmap_demote_DMAP(vm_paddr_t base, vm_size_t len, boolean_t invalidate) { pdp_entry_t *pdpe; pd_entry_t *pde; vm_offset_t va; boolean_t changed; if (len == 0) return; KASSERT(powerof2(len), ("pmap_demote_DMAP: len is not a power of 2")); KASSERT((base & (len - 1)) == 0, ("pmap_demote_DMAP: base is not a multiple of len")); if (len < NBPDP && base < dmaplimit) { va = PHYS_TO_DMAP(base); changed = FALSE; PMAP_LOCK(kernel_pmap); pdpe = pmap_pdpe(kernel_pmap, va); if ((*pdpe & PG_V) == 0) panic("pmap_demote_DMAP: invalid PDPE"); if ((*pdpe & PG_PS) != 0) { if (!pmap_demote_pdpe(kernel_pmap, pdpe, va)) panic("pmap_demote_DMAP: PDPE failed"); changed = TRUE; } if (len < NBPDR) { pde = pmap_pdpe_to_pde(pdpe, va); if ((*pde & PG_V) == 0) panic("pmap_demote_DMAP: invalid PDE"); if ((*pde & PG_PS) != 0) { if (!pmap_demote_pde(kernel_pmap, pde, va)) panic("pmap_demote_DMAP: PDE failed"); changed = TRUE; } } if (changed && invalidate) pmap_invalidate_page(kernel_pmap, va); PMAP_UNLOCK(kernel_pmap); } } /* * 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 pte; vm_paddr_t pa; int val; PMAP_LOCK(pmap); retry: pdep = pmap_pde(pmap, addr); if (pdep != NULL && (*pdep & PG_V)) { 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 { pte = *pmap_pde_to_pte(pdep, addr); 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_int64_t cr3; critical_enter(); pmap = vmspace_pmap(td->td_proc->p_vmspace); oldpmap = PCPU_GET(curpmap); cpuid = PCPU_GET(cpuid); #ifdef 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 cr3 = DMAP_TO_PHYS((vm_offset_t)pmap->pm_pml4); 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; }