/* * 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. * * 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 * $FreeBSD: src/sys/i386/i386/pmap.c,v 1.250.2.18 2002/03/06 22:48:53 silby Exp $ * $DragonFly: src/sys/i386/i386/Attic/pmap.c,v 1.39 2004/05/13 17:40:14 dillon Exp $ */ /* * 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_disable_pse.h" #include "opt_pmap.h" #include "opt_msgbuf.h" #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #if defined(SMP) || defined(APIC_IO) #include #include #endif /* SMP || APIC_IO */ #include #include #include #define PMAP_KEEP_PDIRS #ifndef PMAP_SHPGPERPROC #define PMAP_SHPGPERPROC 200 #endif #if defined(DIAGNOSTIC) #define PMAP_DIAGNOSTIC #endif #define MINPV 2048 #if !defined(PMAP_DIAGNOSTIC) #define PMAP_INLINE __inline #else #define PMAP_INLINE #endif /* * Get PDEs and PTEs for user/kernel address space */ #define pmap_pde(m, v) (&((m)->pm_pdir[(vm_offset_t)(v) >> PDRSHIFT])) #define pdir_pde(m, v) (m[(vm_offset_t)(v) >> PDRSHIFT]) #define pmap_pde_v(pte) ((*(int *)pte & PG_V) != 0) #define pmap_pte_w(pte) ((*(int *)pte & PG_W) != 0) #define pmap_pte_m(pte) ((*(int *)pte & PG_M) != 0) #define pmap_pte_u(pte) ((*(int *)pte & PG_A) != 0) #define pmap_pte_v(pte) ((*(int *)pte & PG_V) != 0) /* * Given a map and a machine independent protection code, * convert to a vax protection code. */ #define pte_prot(m, p) (protection_codes[p]) static int protection_codes[8]; static struct pmap kernel_pmap_store; pmap_t kernel_pmap; vm_paddr_t avail_start; /* PA of first available physical page */ vm_paddr_t avail_end; /* PA of last available physical page */ 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 boolean_t pmap_initialized = FALSE; /* Has pmap_init completed? */ static int pgeflag; /* PG_G or-in */ static int pseflag; /* PG_PS or-in */ static vm_object_t kptobj; static int nkpt; vm_offset_t kernel_vm_end; /* * Data for the pv entry allocation mechanism */ static vm_zone_t pvzone; static struct vm_zone pvzone_store; static struct vm_object pvzone_obj; static int pv_entry_count=0, pv_entry_max=0, pv_entry_high_water=0; static int pmap_pagedaemon_waken = 0; static struct pv_entry *pvinit; /* * All those kernel PT submaps that BSD is so fond of */ pt_entry_t *CMAP1 = 0, *ptmmap; caddr_t CADDR1 = 0, ptvmmap = 0; static pt_entry_t *msgbufmap; struct msgbuf *msgbufp=0; /* * Crashdump maps. */ static pt_entry_t *pt_crashdumpmap; static caddr_t crashdumpmap; extern pt_entry_t *SMPpt; static PMAP_INLINE void free_pv_entry (pv_entry_t pv); static unsigned * get_ptbase (pmap_t pmap); static pv_entry_t get_pv_entry (void); static void i386_protection_init (void); static __inline void pmap_changebit (vm_page_t m, int bit, boolean_t setem); static void pmap_remove_all (vm_page_t m); static vm_page_t pmap_enter_quick (pmap_t pmap, vm_offset_t va, vm_page_t m, vm_page_t mpte); static int pmap_remove_pte (struct pmap *pmap, unsigned *ptq, vm_offset_t sva, pmap_inval_info_t info); static void pmap_remove_page (struct pmap *pmap, vm_offset_t va, pmap_inval_info_t info); static int pmap_remove_entry (struct pmap *pmap, vm_page_t m, vm_offset_t va, pmap_inval_info_t info); static boolean_t pmap_testbit (vm_page_t m, int bit); static void pmap_insert_entry (pmap_t pmap, vm_offset_t va, vm_page_t mpte, vm_page_t m); static vm_page_t pmap_allocpte (pmap_t pmap, vm_offset_t va); static int pmap_release_free_page (pmap_t pmap, vm_page_t p); static vm_page_t _pmap_allocpte (pmap_t pmap, unsigned ptepindex); static unsigned * pmap_pte_quick (pmap_t pmap, vm_offset_t va); static vm_page_t pmap_page_lookup (vm_object_t object, vm_pindex_t pindex); static int pmap_unuse_pt (pmap_t, vm_offset_t, vm_page_t, pmap_inval_info_t); static vm_offset_t pmap_kmem_choose(vm_offset_t addr); static unsigned pdir4mb; /* * Move the kernel virtual free pointer to the next * 4MB. This is used to help improve performance * by using a large (4MB) 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; #ifndef DISABLE_PSE if (cpu_feature & CPUID_PSE) { newaddr = (addr + (NBPDR - 1)) & ~(NBPDR - 1); } #endif return newaddr; } /* * pmap_pte: * * Extract the page table entry associated with the given map/virtual * pair. * * This function may NOT be called from an interrupt. */ PMAP_INLINE unsigned * pmap_pte(pmap_t pmap, vm_offset_t va) { unsigned *pdeaddr; if (pmap) { pdeaddr = (unsigned *) pmap_pde(pmap, va); if (*pdeaddr & PG_PS) return pdeaddr; if (*pdeaddr) { return get_ptbase(pmap) + i386_btop(va); } } return (0); } /* * pmap_pte_quick: * * Super fast pmap_pte routine best used when scanning the pv lists. * This eliminates many course-grained invltlb calls. Note that many of * the pv list scans are across different pmaps and it is very wasteful * to do an entire invltlb when checking a single mapping. * * Should only be called while splvm() is held or from a critical * section. */ static unsigned * pmap_pte_quick(pmap_t pmap, vm_offset_t va) { struct mdglobaldata *gd = mdcpu; unsigned pde, newpf; if ((pde = (unsigned) pmap->pm_pdir[va >> PDRSHIFT]) != 0) { unsigned frame = (unsigned) pmap->pm_pdir[PTDPTDI] & PG_FRAME; unsigned index = i386_btop(va); /* are we current address space or kernel? */ if ((pmap == kernel_pmap) || (frame == (((unsigned) PTDpde) & PG_FRAME))) { return (unsigned *) PTmap + index; } newpf = pde & PG_FRAME; if ( ((* (unsigned *) gd->gd_PMAP1) & PG_FRAME) != newpf) { * (unsigned *) gd->gd_PMAP1 = newpf | PG_RW | PG_V; cpu_invlpg(gd->gd_PADDR1); } return gd->gd_PADDR1 + ((unsigned) index & (NPTEPG - 1)); } return (0); } /* * Bootstrap the system enough to run with virtual memory. * * On the i386 this is called after mapping has already been enabled * and just syncs the pmap module with what has already been done. * [We can't call it easily with mapping off since the kernel is not * mapped with PA == VA, hence we would have to relocate every address * from the linked base (virtual) address "KERNBASE" to the actual * (physical) address starting relative to 0] */ void pmap_bootstrap(firstaddr, loadaddr) vm_paddr_t firstaddr; vm_paddr_t loadaddr; { vm_offset_t va; pt_entry_t *pte; struct mdglobaldata *gd; int i; avail_start = firstaddr; /* * XXX The calculation of virtual_avail is wrong. It's NKPT*PAGE_SIZE too * large. It should instead be correctly calculated in locore.s and * not based on 'first' (which is a physical address, not a virtual * address, for the start of unused physical memory). The kernel * page tables are NOT double mapped and thus should not be included * in this calculation. */ virtual_avail = (vm_offset_t) KERNBASE + firstaddr; virtual_avail = pmap_kmem_choose(virtual_avail); virtual_end = VM_MAX_KERNEL_ADDRESS; /* * Initialize protection array. */ i386_protection_init(); /* * The kernel's pmap is statically allocated so we don't have to use * pmap_create, which is unlikely to work correctly at this part of * the boot sequence (XXX and which no longer exists). */ kernel_pmap = &kernel_pmap_store; kernel_pmap->pm_pdir = (pd_entry_t *)(KERNBASE + (u_int)IdlePTD); kernel_pmap->pm_count = 1; kernel_pmap->pm_active = (cpumask_t)-1; /* don't allow deactivation */ TAILQ_INIT(&kernel_pmap->pm_pvlist); nkpt = NKPT; /* * 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 = (pt_entry_t *) pmap_pte(kernel_pmap, va); /* * CMAP1/CMAP2 are used for zeroing and copying pages. */ SYSMAP(caddr_t, CMAP1, CADDR1, 1) /* * Crashdump maps. */ SYSMAP(caddr_t, pt_crashdumpmap, crashdumpmap, MAXDUMPPGS); /* * ptvmmap is used for reading arbitrary physical pages via * /dev/mem. */ SYSMAP(caddr_t, ptmmap, ptvmmap, 1) /* * msgbufp is used to map the system message buffer. * XXX msgbufmap is not used. */ SYSMAP(struct msgbuf *, msgbufmap, msgbufp, atop(round_page(MSGBUF_SIZE))) virtual_avail = va; *(int *) CMAP1 = 0; for (i = 0; i < NKPT; i++) PTD[i] = 0; /* * PG_G is terribly broken on SMP because we IPI invltlb's in some * cases rather then invl1pg. Actually, I don't even know why it * works under UP because self-referential page table mappings */ #ifdef SMP pgeflag = 0; #else if (cpu_feature & CPUID_PGE) pgeflag = PG_G; #endif /* * Initialize the 4MB page size flag */ pseflag = 0; /* * The 4MB page version of the initial * kernel page mapping. */ pdir4mb = 0; #if !defined(DISABLE_PSE) if (cpu_feature & CPUID_PSE) { unsigned ptditmp; /* * Note that we have enabled PSE mode */ pseflag = PG_PS; ptditmp = *((unsigned *)PTmap + i386_btop(KERNBASE)); ptditmp &= ~(NBPDR - 1); ptditmp |= PG_V | PG_RW | PG_PS | PG_U | pgeflag; pdir4mb = ptditmp; #ifndef SMP /* * Enable the PSE mode. If we are SMP we can't do this * now because the APs will not be able to use it when * they boot up. */ load_cr4(rcr4() | CR4_PSE); /* * We can do the mapping here for the single processor * case. We simply ignore the old page table page from * now on. */ /* * For SMP, we still need 4K pages to bootstrap APs, * PSE will be enabled as soon as all APs are up. */ PTD[KPTDI] = (pd_entry_t)ptditmp; kernel_pmap->pm_pdir[KPTDI] = (pd_entry_t)ptditmp; cpu_invltlb(); #endif } #endif #ifdef APIC_IO if (cpu_apic_address == 0) panic("pmap_bootstrap: no local apic!"); /* local apic is mapped on last page */ SMPpt[NPTEPG - 1] = (pt_entry_t)(PG_V | PG_RW | PG_N | pgeflag | (cpu_apic_address & PG_FRAME)); #endif /* BSP does this itself, AP's get it pre-set */ gd = &CPU_prvspace[0].mdglobaldata; gd->gd_CMAP1 = &SMPpt[1]; gd->gd_CMAP2 = &SMPpt[2]; gd->gd_CMAP3 = &SMPpt[3]; gd->gd_PMAP1 = &SMPpt[4]; gd->gd_CADDR1 = CPU_prvspace[0].CPAGE1; gd->gd_CADDR2 = CPU_prvspace[0].CPAGE2; gd->gd_CADDR3 = CPU_prvspace[0].CPAGE3; gd->gd_PADDR1 = (unsigned *)CPU_prvspace[0].PPAGE1; cpu_invltlb(); } #ifdef SMP /* * Set 4mb pdir for mp startup */ void pmap_set_opt(void) { if (pseflag && (cpu_feature & CPUID_PSE)) { load_cr4(rcr4() | CR4_PSE); if (pdir4mb && mycpu->gd_cpuid == 0) { /* only on BSP */ kernel_pmap->pm_pdir[KPTDI] = PTD[KPTDI] = (pd_entry_t)pdir4mb; cpu_invltlb(); } } } #endif /* * Initialize the pmap module. * Called by vm_init, to initialize any structures that the pmap * system needs to map virtual memory. * pmap_init has been enhanced to support in a fairly consistant * way, discontiguous physical memory. */ void pmap_init(phys_start, phys_end) vm_paddr_t phys_start, phys_end; { int i; int initial_pvs; /* * object for kernel page table pages */ kptobj = vm_object_allocate(OBJT_DEFAULT, NKPDE); /* * Allocate memory for random pmap data structures. Includes the * pv_head_table. */ for(i = 0; i < vm_page_array_size; i++) { vm_page_t m; m = &vm_page_array[i]; TAILQ_INIT(&m->md.pv_list); m->md.pv_list_count = 0; } /* * init the pv free list */ initial_pvs = vm_page_array_size; if (initial_pvs < MINPV) initial_pvs = MINPV; pvzone = &pvzone_store; pvinit = (struct pv_entry *) kmem_alloc(kernel_map, initial_pvs * sizeof (struct pv_entry)); zbootinit(pvzone, "PV ENTRY", sizeof (struct pv_entry), pvinit, vm_page_array_size); /* * Now it is safe to enable pv_table recording. */ pmap_initialized = TRUE; } /* * Initialize the address space (zone) for the pv_entries. Set a * high water mark so that the system can recover from excessive * numbers of pv entries. */ void pmap_init2() { int shpgperproc = PMAP_SHPGPERPROC; TUNABLE_INT_FETCH("vm.pmap.shpgperproc", &shpgperproc); pv_entry_max = shpgperproc * maxproc + vm_page_array_size; TUNABLE_INT_FETCH("vm.pmap.pv_entries", &pv_entry_max); pv_entry_high_water = 9 * (pv_entry_max / 10); zinitna(pvzone, &pvzone_obj, NULL, 0, pv_entry_max, ZONE_INTERRUPT, 1); } /*************************************************** * Low level helper routines..... ***************************************************/ #if defined(PMAP_DIAGNOSTIC) /* * This code checks for non-writeable/modified pages. * This should be an invalid condition. */ static int pmap_nw_modified(pt_entry_t ptea) { int pte; pte = (int) ptea; if ((pte & (PG_M|PG_RW)) == PG_M) return 1; else return 0; } #endif /* * this routine defines the region(s) of memory that should * not be tested for the modified bit. */ static PMAP_INLINE int pmap_track_modified(vm_offset_t va) { if ((va < clean_sva) || (va >= clean_eva)) return 1; else return 0; } static unsigned * get_ptbase(pmap_t pmap) { unsigned frame = (unsigned) pmap->pm_pdir[PTDPTDI] & PG_FRAME; struct globaldata *gd = mycpu; /* are we current address space or kernel? */ if (pmap == kernel_pmap || frame == (((unsigned) PTDpde) & PG_FRAME)) { return (unsigned *) PTmap; } /* otherwise, we are alternate address space */ KKASSERT(gd->gd_intr_nesting_level == 0 && (gd->gd_curthread->td_flags & TDF_INTTHREAD) == 0); if (frame != (((unsigned) APTDpde) & PG_FRAME)) { APTDpde = (pd_entry_t)(frame | PG_RW | PG_V); /* The page directory is not shared between CPUs */ cpu_invltlb(); } return (unsigned *) APTmap; } /* * pmap_extract: * * Extract the physical page address associated with the map/VA pair. * * This function may not be called from an interrupt if the pmap is * not kernel_pmap. */ vm_paddr_t pmap_extract(pmap_t pmap, vm_offset_t va) { vm_offset_t rtval; vm_offset_t pdirindex; pdirindex = va >> PDRSHIFT; if (pmap && (rtval = (unsigned) pmap->pm_pdir[pdirindex])) { unsigned *pte; if ((rtval & PG_PS) != 0) { rtval &= ~(NBPDR - 1); rtval |= va & (NBPDR - 1); return rtval; } pte = get_ptbase(pmap) + i386_btop(va); rtval = ((*pte & PG_FRAME) | (va & PAGE_MASK)); return rtval; } return 0; } /* * Extract user accessible page only, return NULL if the page is not * present or if it's current state is not sufficient. Caller will * generally call vm_fault() on failure and try again. */ vm_page_t pmap_extract_vmpage(pmap_t pmap, vm_offset_t va, int prot) { vm_offset_t rtval; vm_offset_t pdirindex; pdirindex = va >> PDRSHIFT; if (pmap && (rtval = (unsigned) pmap->pm_pdir[pdirindex])) { unsigned *pte; vm_page_t m; if ((rtval & PG_PS) != 0) { if ((rtval & (PG_V|PG_U)) != (PG_V|PG_U)) return (NULL); if ((prot & VM_PROT_WRITE) && (rtval & PG_RW) == 0) return (NULL); rtval &= ~(NBPDR - 1); rtval |= va & (NBPDR - 1); m = PHYS_TO_VM_PAGE(rtval); } else { pte = get_ptbase(pmap) + i386_btop(va); if ((*pte & (PG_V|PG_U)) != (PG_V|PG_U)) return (NULL); if ((prot & VM_PROT_WRITE) && (*pte & PG_RW) == 0) return (NULL); rtval = ((*pte & PG_FRAME) | (va & PAGE_MASK)); m = PHYS_TO_VM_PAGE(rtval); } return(m); } return (NULL); } /*************************************************** * Low level mapping routines..... ***************************************************/ /* * add a wired page to the kva * note that in order for the mapping to take effect -- you * should do a invltlb after doing the pmap_kenter... */ void pmap_kenter(vm_offset_t va, vm_paddr_t pa) { unsigned *pte; unsigned npte; pmap_inval_info info; pmap_inval_init(&info); pmap_inval_add(&info, kernel_pmap, va); npte = pa | PG_RW | PG_V | pgeflag; pte = (unsigned *)vtopte(va); *pte = npte; pmap_inval_flush(&info); } void pmap_kenter_quick(vm_offset_t va, vm_paddr_t pa) { unsigned *pte; unsigned npte; npte = pa | PG_RW | PG_V | pgeflag; pte = (unsigned *)vtopte(va); *pte = npte; cpu_invlpg((void *)va); } void pmap_kenter_sync(vm_offset_t va) { pmap_inval_info info; pmap_inval_init(&info); pmap_inval_add(&info, kernel_pmap, va); pmap_inval_flush(&info); } void pmap_kenter_sync_quick(vm_offset_t va) { cpu_invlpg((void *)va); } /* * remove a page from the kernel pagetables */ void pmap_kremove(vm_offset_t va) { unsigned *pte; pmap_inval_info info; pmap_inval_init(&info); pmap_inval_add(&info, kernel_pmap, va); pte = (unsigned *)vtopte(va); *pte = 0; pmap_inval_flush(&info); } void pmap_kremove_quick(vm_offset_t va) { unsigned *pte; pte = (unsigned *)vtopte(va); *pte = 0; cpu_invlpg((void *)va); } /* * Used to map a range of physical addresses into kernel * virtual address space. * * For now, VM is already on, we only need to map the * specified memory. */ vm_offset_t pmap_map(vm_offset_t virt, vm_paddr_t start, vm_paddr_t end, int prot) { while (start < end) { pmap_kenter(virt, start); virt += PAGE_SIZE; start += PAGE_SIZE; } return (virt); } /* * 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. */ void pmap_qenter(vm_offset_t va, vm_page_t *m, int count) { vm_offset_t end_va; end_va = va + count * PAGE_SIZE; while (va < end_va) { unsigned *pte; pte = (unsigned *)vtopte(va); *pte = VM_PAGE_TO_PHYS(*m) | PG_RW | PG_V | pgeflag; cpu_invlpg((void *)va); va += PAGE_SIZE; m++; } #ifdef SMP smp_invltlb(); /* XXX */ #endif } void pmap_qenter2(vm_offset_t va, vm_page_t *m, int count, cpumask_t *mask) { vm_offset_t end_va; cpumask_t cmask = mycpu->gd_cpumask; end_va = va + count * PAGE_SIZE; while (va < end_va) { unsigned *pte; unsigned pteval; /* * Install the new PTE. If the pte changed from the prior * mapping we must reset the cpu mask and invalidate the page. * If the pte is the same but we have not seen it on the * current cpu, invlpg the existing mapping. Otherwise the * entry is optimal and no invalidation is required. */ pte = (unsigned *)vtopte(va); pteval = VM_PAGE_TO_PHYS(*m) | PG_A | PG_RW | PG_V | pgeflag; if (*pte != pteval) { *mask = 0; *pte = pteval; cpu_invlpg((void *)va); } else if ((*mask & cmask) == 0) { cpu_invlpg((void *)va); } va += PAGE_SIZE; m++; } *mask |= cmask; } /* * this routine jerks page mappings from the * kernel -- it is meant only for temporary mappings. */ void pmap_qremove(vm_offset_t va, int count) { vm_offset_t end_va; end_va = va + count*PAGE_SIZE; while (va < end_va) { unsigned *pte; pte = (unsigned *)vtopte(va); *pte = 0; cpu_invlpg((void *)va); va += PAGE_SIZE; } #ifdef SMP smp_invltlb(); #endif } /* * This routine works like vm_page_lookup() but also blocks as long as the * page is busy. This routine does not busy the page it returns. * * Unless the caller is managing objects whos pages are in a known state, * the call should be made at splvm() so the page's object association * remains valid on return. */ static vm_page_t pmap_page_lookup(vm_object_t object, vm_pindex_t pindex) { vm_page_t m; retry: m = vm_page_lookup(object, pindex); if (m && vm_page_sleep_busy(m, FALSE, "pplookp")) goto retry; return(m); } /* * Create a new thread and optionally associate it with a (new) process. * NOTE! the new thread's cpu may not equal the current cpu. */ void pmap_init_thread(thread_t td) { td->td_pcb = (struct pcb *)(td->td_kstack + UPAGES * PAGE_SIZE) - 1; td->td_savefpu = &td->td_pcb->pcb_save; td->td_sp = (char *)td->td_pcb - 16; } /* * Create the UPAGES for a new process. * This routine directly affects the fork perf for a process. */ void pmap_init_proc(struct proc *p, struct thread *td) { p->p_addr = (void *)td->td_kstack; p->p_thread = td; td->td_proc = p; td->td_switch = cpu_heavy_switch; #ifdef SMP td->td_mpcount = 1; #endif bzero(p->p_addr, sizeof(*p->p_addr)); } /* * Dispose the UPAGES for a process that has exited. * This routine directly impacts the exit perf of a process. */ struct thread * pmap_dispose_proc(struct proc *p) { struct thread *td; KASSERT(p->p_lock == 0, ("attempt to dispose referenced proc! %p", p)); if ((td = p->p_thread) != NULL) { p->p_thread = NULL; td->td_proc = NULL; } p->p_addr = NULL; return(td); } /* * Allow the UPAGES for a process to be prejudicially paged out. */ void pmap_swapout_proc(struct proc *p) { #if 0 int i; int s; vm_object_t upobj; vm_page_t m; upobj = p->p_upages_obj; /* * Unwiring the pages allow them to be paged to their backing store * (swap). * * splvm() protection not required since nobody will be messing with * the pages but us. */ for (i = 0; i < UPAGES; i++) { if ((m = vm_page_lookup(upobj, i)) == NULL) panic("pmap_swapout_proc: upage already missing???"); vm_page_dirty(m); vm_page_unwire(m, 0); pmap_kremove((vm_offset_t)p->p_addr + (PAGE_SIZE * i)); } #endif } /* * Bring the UPAGES for a specified process back in. */ void pmap_swapin_proc(struct proc *p) { #if 0 int i,rv; vm_object_t upobj; vm_page_t m; /* * splvm() protection not required since nobody will be messing with * the pages but us. */ upobj = p->p_upages_obj; for (i = 0; i < UPAGES; i++) { m = vm_page_grab(upobj, i, VM_ALLOC_NORMAL | VM_ALLOC_RETRY); pmap_kenter((vm_offset_t)p->p_addr + (i * PAGE_SIZE), VM_PAGE_TO_PHYS(m)); if (m->valid != VM_PAGE_BITS_ALL) { rv = vm_pager_get_pages(upobj, &m, 1, 0); if (rv != VM_PAGER_OK) panic("pmap_swapin_proc: cannot get upages for proc: %d\n", p->p_pid); m = vm_page_lookup(upobj, i); m->valid = VM_PAGE_BITS_ALL; } vm_page_wire(m); vm_page_wakeup(m); vm_page_flag_set(m, PG_MAPPED | PG_WRITEABLE); } #endif } /*************************************************** * Page table page management routines..... ***************************************************/ /* * This routine unholds page table pages, and if the hold count * drops to zero, then it decrements the wire count. */ static int _pmap_unwire_pte_hold(pmap_t pmap, vm_page_t m, pmap_inval_info_t info) { pmap_inval_flush(info); while (vm_page_sleep_busy(m, FALSE, "pmuwpt")) ; if (m->hold_count == 0) { vm_offset_t pteva; /* * unmap the page table page */ pmap_inval_add(info, pmap, -1); pmap->pm_pdir[m->pindex] = 0; --pmap->pm_stats.resident_count; if ((((unsigned)pmap->pm_pdir[PTDPTDI]) & PG_FRAME) == (((unsigned) PTDpde) & PG_FRAME)) { /* * Do a invltlb to make the invalidated mapping * take effect immediately. */ pteva = UPT_MIN_ADDRESS + i386_ptob(m->pindex); } if (pmap->pm_ptphint == m) pmap->pm_ptphint = NULL; /* * If the page is finally unwired, simply free it. */ --m->wire_count; if (m->wire_count == 0) { vm_page_flash(m); vm_page_busy(m); vm_page_free_zero(m); --vmstats.v_wire_count; } return 1; } return 0; } static PMAP_INLINE int pmap_unwire_pte_hold(pmap_t pmap, vm_page_t m, pmap_inval_info_t info) { vm_page_unhold(m); if (m->hold_count == 0) return _pmap_unwire_pte_hold(pmap, m, info); else return 0; } /* * After removing a page table entry, this routine is used to * conditionally free the page, and manage the hold/wire counts. */ static int pmap_unuse_pt(pmap_t pmap, vm_offset_t va, vm_page_t mpte, pmap_inval_info_t info) { unsigned ptepindex; if (va >= UPT_MIN_ADDRESS) return 0; if (mpte == NULL) { ptepindex = (va >> PDRSHIFT); if (pmap->pm_ptphint && (pmap->pm_ptphint->pindex == ptepindex)) { mpte = pmap->pm_ptphint; } else { pmap_inval_flush(info); mpte = pmap_page_lookup( pmap->pm_pteobj, ptepindex); pmap->pm_ptphint = mpte; } } return pmap_unwire_pte_hold(pmap, mpte, info); } void pmap_pinit0(struct pmap *pmap) { pmap->pm_pdir = (pd_entry_t *)kmem_alloc_pageable(kernel_map, PAGE_SIZE); pmap_kenter((vm_offset_t)pmap->pm_pdir, (vm_offset_t) IdlePTD); pmap->pm_count = 1; pmap->pm_active = 0; pmap->pm_ptphint = NULL; TAILQ_INIT(&pmap->pm_pvlist); bzero(&pmap->pm_stats, sizeof pmap->pm_stats); } /* * Initialize a preallocated and zeroed pmap structure, * such as one in a vmspace structure. */ void pmap_pinit(struct pmap *pmap) { vm_page_t ptdpg; /* * No need to allocate page table space yet but we do need a valid * page directory table. */ if (pmap->pm_pdir == NULL) { pmap->pm_pdir = (pd_entry_t *)kmem_alloc_pageable(kernel_map, PAGE_SIZE); } /* * allocate object for the ptes */ if (pmap->pm_pteobj == NULL) pmap->pm_pteobj = vm_object_allocate( OBJT_DEFAULT, PTDPTDI + 1); /* * allocate the page directory page */ ptdpg = vm_page_grab( pmap->pm_pteobj, PTDPTDI, VM_ALLOC_NORMAL | VM_ALLOC_RETRY); ptdpg->wire_count = 1; ++vmstats.v_wire_count; vm_page_flag_clear(ptdpg, PG_MAPPED | PG_BUSY); /* not usually mapped*/ ptdpg->valid = VM_PAGE_BITS_ALL; pmap_kenter((vm_offset_t)pmap->pm_pdir, VM_PAGE_TO_PHYS(ptdpg)); if ((ptdpg->flags & PG_ZERO) == 0) bzero(pmap->pm_pdir, PAGE_SIZE); pmap->pm_pdir[MPPTDI] = PTD[MPPTDI]; /* install self-referential address mapping entry */ *(unsigned *) (pmap->pm_pdir + PTDPTDI) = VM_PAGE_TO_PHYS(ptdpg) | PG_V | PG_RW | PG_A | PG_M; pmap->pm_count = 1; pmap->pm_active = 0; pmap->pm_ptphint = NULL; TAILQ_INIT(&pmap->pm_pvlist); bzero(&pmap->pm_stats, sizeof pmap->pm_stats); } /* * Wire in kernel global address entries. To avoid a race condition * between pmap initialization and pmap_growkernel, this procedure * should be called after the vmspace is attached to the process * but before this pmap is activated. */ void pmap_pinit2(struct pmap *pmap) { /* XXX copies current process, does not fill in MPPTDI */ bcopy(PTD + KPTDI, pmap->pm_pdir + KPTDI, nkpt * PTESIZE); } static int pmap_release_free_page(struct pmap *pmap, vm_page_t p) { unsigned *pde = (unsigned *) pmap->pm_pdir; /* * This code optimizes the case of freeing non-busy * page-table pages. Those pages are zero now, and * might as well be placed directly into the zero queue. */ if (vm_page_sleep_busy(p, FALSE, "pmaprl")) return 0; vm_page_busy(p); /* * Remove the page table page from the processes address space. */ pde[p->pindex] = 0; pmap->pm_stats.resident_count--; if (p->hold_count) { panic("pmap_release: freeing held page table page"); } /* * Page directory pages need to have the kernel * stuff cleared, so they can go into the zero queue also. */ if (p->pindex == PTDPTDI) { bzero(pde + KPTDI, nkpt * PTESIZE); pde[MPPTDI] = 0; pde[APTDPTDI] = 0; pmap_kremove((vm_offset_t)pmap->pm_pdir); } if (pmap->pm_ptphint && (pmap->pm_ptphint->pindex == p->pindex)) pmap->pm_ptphint = NULL; p->wire_count--; vmstats.v_wire_count--; vm_page_free_zero(p); return 1; } /* * this routine is called if the page table page is not * mapped correctly. */ static vm_page_t _pmap_allocpte(pmap_t pmap, unsigned ptepindex) { vm_offset_t pteva, ptepa; vm_page_t m; /* * Find or fabricate a new pagetable page */ m = vm_page_grab(pmap->pm_pteobj, ptepindex, VM_ALLOC_NORMAL | VM_ALLOC_ZERO | VM_ALLOC_RETRY); KASSERT(m->queue == PQ_NONE, ("_pmap_allocpte: %p->queue != PQ_NONE", m)); if (m->wire_count == 0) vmstats.v_wire_count++; m->wire_count++; /* * Increment the hold count for the page table page * (denoting a new mapping.) */ m->hold_count++; /* * Map the pagetable page into the process address space, if * it isn't already there. */ pmap->pm_stats.resident_count++; ptepa = VM_PAGE_TO_PHYS(m); pmap->pm_pdir[ptepindex] = (pd_entry_t) (ptepa | PG_U | PG_RW | PG_V | PG_A | PG_M); /* * Set the page table hint */ pmap->pm_ptphint = m; /* * Try to use the new mapping, but if we cannot, then * do it with the routine that maps the page explicitly. */ if ((m->flags & PG_ZERO) == 0) { if ((((unsigned)pmap->pm_pdir[PTDPTDI]) & PG_FRAME) == (((unsigned) PTDpde) & PG_FRAME)) { pteva = UPT_MIN_ADDRESS + i386_ptob(ptepindex); bzero((caddr_t) pteva, PAGE_SIZE); } else { pmap_zero_page(ptepa); } } m->valid = VM_PAGE_BITS_ALL; vm_page_flag_clear(m, PG_ZERO); vm_page_flag_set(m, PG_MAPPED); vm_page_wakeup(m); return m; } static vm_page_t pmap_allocpte(pmap_t pmap, vm_offset_t va) { unsigned ptepindex; vm_offset_t ptepa; vm_page_t m; /* * Calculate pagetable page index */ ptepindex = va >> PDRSHIFT; /* * Get the page directory entry */ ptepa = (vm_offset_t) pmap->pm_pdir[ptepindex]; /* * This supports switching from a 4MB page to a * normal 4K page. */ if (ptepa & PG_PS) { pmap->pm_pdir[ptepindex] = 0; ptepa = 0; cpu_invltlb(); smp_invltlb(); } /* * If the page table page is mapped, we just increment the * hold count, and activate it. */ if (ptepa) { /* * In order to get the page table page, try the * hint first. */ if (pmap->pm_ptphint && (pmap->pm_ptphint->pindex == ptepindex)) { m = pmap->pm_ptphint; } else { m = pmap_page_lookup( pmap->pm_pteobj, ptepindex); pmap->pm_ptphint = m; } m->hold_count++; return m; } /* * Here if the pte page isn't mapped, or if it has been deallocated. */ return _pmap_allocpte(pmap, ptepindex); } /*************************************************** * 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(struct pmap *pmap) { vm_page_t p,n,ptdpg; vm_object_t object = pmap->pm_pteobj; int curgeneration; int s; #if defined(DIAGNOSTIC) if (object->ref_count != 1) panic("pmap_release: pteobj reference count != 1"); #endif ptdpg = NULL; retry: s = splvm(); curgeneration = object->generation; for (p = TAILQ_FIRST(&object->memq); p != NULL; p = n) { n = TAILQ_NEXT(p, listq); if (p->pindex == PTDPTDI) { ptdpg = p; continue; } while (1) { if (!pmap_release_free_page(pmap, p) && (object->generation != curgeneration)) { splx(s); goto retry; } } } splx(s); if (ptdpg && !pmap_release_free_page(pmap, ptdpg)) goto retry; } static int kvm_size(SYSCTL_HANDLER_ARGS) { unsigned long ksize = VM_MAX_KERNEL_ADDRESS - KERNBASE; return sysctl_handle_long(oidp, &ksize, 0, req); } SYSCTL_PROC(_vm, OID_AUTO, kvm_size, CTLTYPE_LONG|CTLFLAG_RD, 0, 0, kvm_size, "IU", "Size of KVM"); static int kvm_free(SYSCTL_HANDLER_ARGS) { unsigned long kfree = VM_MAX_KERNEL_ADDRESS - kernel_vm_end; return sysctl_handle_long(oidp, &kfree, 0, req); } SYSCTL_PROC(_vm, OID_AUTO, kvm_free, CTLTYPE_LONG|CTLFLAG_RD, 0, 0, kvm_free, "IU", "Amount of KVM free"); /* * grow the number of kernel page table entries, if needed */ void pmap_growkernel(vm_offset_t addr) { struct proc *p; struct pmap *pmap; int s; vm_offset_t ptppaddr; vm_page_t nkpg; pd_entry_t newpdir; s = splhigh(); if (kernel_vm_end == 0) { kernel_vm_end = KERNBASE; nkpt = 0; while (pdir_pde(PTD, kernel_vm_end)) { kernel_vm_end = (kernel_vm_end + PAGE_SIZE * NPTEPG) & ~(PAGE_SIZE * NPTEPG - 1); nkpt++; } } addr = (addr + PAGE_SIZE * NPTEPG) & ~(PAGE_SIZE * NPTEPG - 1); while (kernel_vm_end < addr) { if (pdir_pde(PTD, kernel_vm_end)) { kernel_vm_end = (kernel_vm_end + PAGE_SIZE * NPTEPG) & ~(PAGE_SIZE * NPTEPG - 1); continue; } /* * This index is bogus, but out of the way */ nkpg = vm_page_alloc(kptobj, nkpt, VM_ALLOC_NORMAL | VM_ALLOC_SYSTEM | VM_ALLOC_INTERRUPT); if (nkpg == NULL) panic("pmap_growkernel: no memory to grow kernel"); nkpt++; vm_page_wire(nkpg); ptppaddr = VM_PAGE_TO_PHYS(nkpg); pmap_zero_page(ptppaddr); newpdir = (pd_entry_t) (ptppaddr | PG_V | PG_RW | PG_A | PG_M); pdir_pde(PTD, kernel_vm_end) = newpdir; FOREACH_PROC_IN_SYSTEM(p) { if (p->p_vmspace) { pmap = vmspace_pmap(p->p_vmspace); *pmap_pde(pmap, kernel_vm_end) = newpdir; } } *pmap_pde(kernel_pmap, kernel_vm_end) = newpdir; kernel_vm_end = (kernel_vm_end + PAGE_SIZE * NPTEPG) & ~(PAGE_SIZE * NPTEPG - 1); } splx(s); } /* * Retire the given physical map from service. * Should only be called if the map contains * no valid mappings. */ void pmap_destroy(pmap_t pmap) { int count; if (pmap == NULL) return; count = --pmap->pm_count; if (count == 0) { pmap_release(pmap); panic("destroying a pmap is not yet implemented"); } } /* * Add a reference to the specified pmap. */ void pmap_reference(pmap_t pmap) { if (pmap != NULL) { pmap->pm_count++; } } /*************************************************** * page management routines. ***************************************************/ /* * free the pv_entry back to the free list. This function may be * called from an interrupt. */ static PMAP_INLINE void free_pv_entry(pv_entry_t pv) { pv_entry_count--; zfree(pvzone, pv); } /* * get a new pv_entry, allocating a block from the system * when needed. This function may be called from an interrupt. */ static pv_entry_t get_pv_entry(void) { pv_entry_count++; if (pv_entry_high_water && (pv_entry_count > pv_entry_high_water) && (pmap_pagedaemon_waken == 0)) { pmap_pagedaemon_waken = 1; wakeup (&vm_pages_needed); } return zalloc(pvzone); } /* * This routine is very drastic, but can save the system * in a pinch. */ void pmap_collect(void) { int i; vm_page_t m; static int warningdone=0; if (pmap_pagedaemon_waken == 0) return; if (warningdone < 5) { printf("pmap_collect: collecting pv entries -- suggest increasing PMAP_SHPGPERPROC\n"); warningdone++; } for(i = 0; i < vm_page_array_size; i++) { m = &vm_page_array[i]; if (m->wire_count || m->hold_count || m->busy || (m->flags & PG_BUSY)) continue; pmap_remove_all(m); } pmap_pagedaemon_waken = 0; } /* * If it is the first entry on the list, it is actually * in the header and we must copy the following entry up * to the header. Otherwise we must search the list for * the entry. In either case we free the now unused entry. */ static int pmap_remove_entry(struct pmap *pmap, vm_page_t m, vm_offset_t va, pmap_inval_info_t info) { pv_entry_t pv; int rtval; int s; s = splvm(); if (m->md.pv_list_count < pmap->pm_stats.resident_count) { TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) { if (pmap == pv->pv_pmap && va == pv->pv_va) break; } } else { TAILQ_FOREACH(pv, &pmap->pm_pvlist, pv_plist) { if (va == pv->pv_va) break; } } rtval = 0; if (pv) { rtval = pmap_unuse_pt(pmap, va, pv->pv_ptem, info); TAILQ_REMOVE(&m->md.pv_list, pv, pv_list); m->md.pv_list_count--; if (TAILQ_FIRST(&m->md.pv_list) == NULL) vm_page_flag_clear(m, PG_MAPPED | PG_WRITEABLE); TAILQ_REMOVE(&pmap->pm_pvlist, pv, pv_plist); free_pv_entry(pv); } splx(s); return rtval; } /* * 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 mpte, vm_page_t m) { int s; pv_entry_t pv; s = splvm(); pv = get_pv_entry(); pv->pv_va = va; pv->pv_pmap = pmap; pv->pv_ptem = mpte; TAILQ_INSERT_TAIL(&pmap->pm_pvlist, pv, pv_plist); TAILQ_INSERT_TAIL(&m->md.pv_list, pv, pv_list); m->md.pv_list_count++; splx(s); } /* * pmap_remove_pte: do the things to unmap a page in a process */ static int pmap_remove_pte(struct pmap *pmap, unsigned *ptq, vm_offset_t va, pmap_inval_info_t info) { unsigned oldpte; vm_page_t m; pmap_inval_add(info, pmap, va); oldpte = loadandclear(ptq); if (oldpte & PG_W) pmap->pm_stats.wired_count -= 1; /* * Machines that don't support invlpg, also don't support * PG_G. XXX PG_G is disabled for SMP so don't worry about * the SMP case. */ if (oldpte & PG_G) cpu_invlpg((void *)va); pmap->pm_stats.resident_count -= 1; if (oldpte & PG_MANAGED) { m = PHYS_TO_VM_PAGE(oldpte); if (oldpte & PG_M) { #if defined(PMAP_DIAGNOSTIC) if (pmap_nw_modified((pt_entry_t) oldpte)) { printf( "pmap_remove: modified page not writable: va: 0x%x, pte: 0x%x\n", va, oldpte); } #endif if (pmap_track_modified(va)) vm_page_dirty(m); } if (oldpte & PG_A) vm_page_flag_set(m, PG_REFERENCED); return pmap_remove_entry(pmap, m, va, info); } else { return pmap_unuse_pt(pmap, va, NULL, info); } return 0; } /* * pmap_remove_page: * * Remove a single page from a process address space. * * This function may not be called from an interrupt if the pmap is * not kernel_pmap. */ static void pmap_remove_page(struct pmap *pmap, vm_offset_t va, pmap_inval_info_t info) { unsigned *ptq; /* * if there is no pte for this address, just skip it!!! Otherwise * get a local va for mappings for this pmap and remove the entry. */ if (*pmap_pde(pmap, va) != 0) { ptq = get_ptbase(pmap) + i386_btop(va); if (*ptq) { pmap_remove_pte(pmap, ptq, va, info); } } } /* * pmap_remove: * * 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. * * This function may not be called from an interrupt if the pmap is * not kernel_pmap. */ void pmap_remove(struct pmap *pmap, vm_offset_t sva, vm_offset_t eva) { unsigned *ptbase; vm_offset_t pdnxt; vm_offset_t ptpaddr; vm_offset_t sindex, eindex; struct pmap_inval_info info; if (pmap == NULL) return; if (pmap->pm_stats.resident_count == 0) return; pmap_inval_init(&info); /* * special handling of removing one page. a very * common operation and easy to short circuit some * code. */ if (((sva + PAGE_SIZE) == eva) && (((unsigned) pmap->pm_pdir[(sva >> PDRSHIFT)] & PG_PS) == 0)) { pmap_remove_page(pmap, sva, &info); pmap_inval_flush(&info); return; } /* * Get a local virtual address for the mappings that are being * worked with. */ ptbase = get_ptbase(pmap); sindex = i386_btop(sva); eindex = i386_btop(eva); for (; sindex < eindex; sindex = pdnxt) { unsigned pdirindex; /* * Calculate index for next page table. */ pdnxt = ((sindex + NPTEPG) & ~(NPTEPG - 1)); if (pmap->pm_stats.resident_count == 0) break; pdirindex = sindex / NPDEPG; if (((ptpaddr = (unsigned) pmap->pm_pdir[pdirindex]) & PG_PS) != 0) { pmap_inval_add(&info, pmap, -1); pmap->pm_pdir[pdirindex] = 0; pmap->pm_stats.resident_count -= NBPDR / PAGE_SIZE; continue; } /* * Weed out invalid mappings. Note: we assume that the page * directory table is always allocated, and in kernel virtual. */ if (ptpaddr == 0) continue; /* * Limit our scan to either the end of the va represented * by the current page table page, or to the end of the * range being removed. */ if (pdnxt > eindex) { pdnxt = eindex; } for (; sindex != pdnxt; sindex++) { vm_offset_t va; if (ptbase[sindex] == 0) continue; va = i386_ptob(sindex); if (pmap_remove_pte(pmap, ptbase + sindex, va, &info)) break; } } pmap_inval_flush(&info); } /* * pmap_remove_all: * * Removes this physical page from all physical maps in which it resides. * Reflects back modify bits to the pager. * * This routine may not be called from an interrupt. */ static void pmap_remove_all(vm_page_t m) { struct pmap_inval_info info; unsigned *pte, tpte; pv_entry_t pv; int s; #if defined(PMAP_DIAGNOSTIC) /* * XXX this makes pmap_page_protect(NONE) illegal for non-managed * pages! */ if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) { panic("pmap_page_protect: illegal for unmanaged page, va: 0x%08llx", (long long)VM_PAGE_TO_PHYS(m)); } #endif pmap_inval_init(&info); s = splvm(); while ((pv = TAILQ_FIRST(&m->md.pv_list)) != NULL) { pv->pv_pmap->pm_stats.resident_count--; pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va); pmap_inval_add(&info, pv->pv_pmap, pv->pv_va); tpte = loadandclear(pte); if (tpte & PG_W) pv->pv_pmap->pm_stats.wired_count--; if (tpte & PG_A) vm_page_flag_set(m, PG_REFERENCED); /* * Update the vm_page_t clean and reference bits. */ if (tpte & PG_M) { #if defined(PMAP_DIAGNOSTIC) if (pmap_nw_modified((pt_entry_t) tpte)) { printf( "pmap_remove_all: modified page not writable: va: 0x%x, pte: 0x%x\n", pv->pv_va, tpte); } #endif if (pmap_track_modified(pv->pv_va)) vm_page_dirty(m); } TAILQ_REMOVE(&pv->pv_pmap->pm_pvlist, pv, pv_plist); TAILQ_REMOVE(&m->md.pv_list, pv, pv_list); m->md.pv_list_count--; pmap_unuse_pt(pv->pv_pmap, pv->pv_va, pv->pv_ptem, &info); free_pv_entry(pv); } vm_page_flag_clear(m, PG_MAPPED | PG_WRITEABLE); splx(s); pmap_inval_flush(&info); } /* * pmap_protect: * * Set the physical protection on the specified range of this map * as requested. * * This function may not be called from an interrupt if the map is * not the kernel_pmap. */ void pmap_protect(pmap_t pmap, vm_offset_t sva, vm_offset_t eva, vm_prot_t prot) { unsigned *ptbase; vm_offset_t pdnxt, ptpaddr; vm_pindex_t sindex, eindex; pmap_inval_info info; if (pmap == NULL) return; if ((prot & VM_PROT_READ) == VM_PROT_NONE) { pmap_remove(pmap, sva, eva); return; } if (prot & VM_PROT_WRITE) return; pmap_inval_init(&info); ptbase = get_ptbase(pmap); sindex = i386_btop(sva); eindex = i386_btop(eva); for (; sindex < eindex; sindex = pdnxt) { unsigned pdirindex; pdnxt = ((sindex + NPTEPG) & ~(NPTEPG - 1)); pdirindex = sindex / NPDEPG; if (((ptpaddr = (unsigned) pmap->pm_pdir[pdirindex]) & PG_PS) != 0) { pmap_inval_add(&info, pmap, -1); (unsigned) pmap->pm_pdir[pdirindex] &= ~(PG_M|PG_RW); pmap->pm_stats.resident_count -= NBPDR / PAGE_SIZE; continue; } /* * Weed out invalid mappings. Note: we assume that the page * directory table is always allocated, and in kernel virtual. */ if (ptpaddr == 0) continue; if (pdnxt > eindex) { pdnxt = eindex; } for (; sindex != pdnxt; sindex++) { unsigned pbits; vm_page_t m; /* XXX this isn't optimal */ pmap_inval_add(&info, pmap, i386_ptob(sindex)); pbits = ptbase[sindex]; if (pbits & PG_MANAGED) { m = NULL; if (pbits & PG_A) { m = PHYS_TO_VM_PAGE(pbits); vm_page_flag_set(m, PG_REFERENCED); pbits &= ~PG_A; } if (pbits & PG_M) { if (pmap_track_modified(i386_ptob(sindex))) { if (m == NULL) m = PHYS_TO_VM_PAGE(pbits); vm_page_dirty(m); pbits &= ~PG_M; } } } pbits &= ~PG_RW; if (pbits != ptbase[sindex]) { ptbase[sindex] = pbits; } } } pmap_inval_flush(&info); } /* * 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_page_t m, vm_prot_t prot, boolean_t wired) { vm_paddr_t pa; unsigned *pte; vm_paddr_t opa; vm_offset_t origpte, newpte; vm_page_t mpte; pmap_inval_info info; if (pmap == NULL) return; va &= PG_FRAME; #ifdef PMAP_DIAGNOSTIC if (va > VM_MAX_KERNEL_ADDRESS) panic("pmap_enter: toobig"); if ((va >= UPT_MIN_ADDRESS) && (va < UPT_MAX_ADDRESS)) panic("pmap_enter: invalid to pmap_enter page table pages (va: 0x%x)", va); #endif mpte = NULL; /* * In the case that a page table page is not * resident, we are creating it here. */ if (va < UPT_MIN_ADDRESS) { mpte = pmap_allocpte(pmap, va); } pmap_inval_init(&info); pte = pmap_pte(pmap, va); /* * Page Directory table entry not valid, we need a new PT page */ if (pte == NULL) { panic("pmap_enter: invalid page directory pdir=%x, va=0x%x\n", (unsigned) pmap->pm_pdir[PTDPTDI], va); } pa = VM_PAGE_TO_PHYS(m) & PG_FRAME; pmap_inval_add(&info, pmap, va); /* XXX non-optimal */ origpte = *(vm_offset_t *)pte; opa = origpte & PG_FRAME; if (origpte & PG_PS) panic("pmap_enter: attempted pmap_enter on 4MB page"); /* * 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--; #if defined(PMAP_DIAGNOSTIC) if (pmap_nw_modified((pt_entry_t) origpte)) { printf( "pmap_enter: modified page not writable: va: 0x%x, pte: 0x%x\n", va, origpte); } #endif /* * Remove extra pte reference */ if (mpte) mpte->hold_count--; if ((prot & VM_PROT_WRITE) && (origpte & PG_V)) { if ((origpte & PG_RW) == 0) *pte |= PG_RW; pmap_inval_flush(&info); return; } /* * We might be turning off write access to the page, * so we go ahead and sense modify status. */ if (origpte & PG_MANAGED) { if ((origpte & PG_M) && pmap_track_modified(va)) { vm_page_t om; om = PHYS_TO_VM_PAGE(opa); vm_page_dirty(om); } pa |= PG_MANAGED; } goto validate; } /* * Mapping has changed, invalidate old range and fall through to * handle validating new mapping. */ if (opa) { int err; err = pmap_remove_pte(pmap, pte, va, &info); if (err) panic("pmap_enter: pte vanished, va: 0x%x", va); } /* * Enter on the PV list if part of our managed memory. Note that we * raise IPL while manipulating pv_table since pmap_enter can be * called at interrupt time. */ if (pmap_initialized && (m->flags & (PG_FICTITIOUS|PG_UNMANAGED)) == 0) { pmap_insert_entry(pmap, va, mpte, m); pa |= PG_MANAGED; } /* * Increment counters */ pmap->pm_stats.resident_count++; if (wired) pmap->pm_stats.wired_count++; validate: /* * Now validate mapping with desired protection/wiring. */ newpte = (vm_offset_t) (pa | pte_prot(pmap, prot) | PG_V); if (wired) newpte |= PG_W; if (va < UPT_MIN_ADDRESS) newpte |= PG_U; if (pmap == kernel_pmap) newpte |= pgeflag; /* * if the mapping or permission bits are different, we need * to update the pte. */ if ((origpte & ~(PG_M|PG_A)) != newpte) { *pte = newpte | PG_A; } pmap_inval_flush(&info); } /* * this code makes some *MAJOR* assumptions: * 1. Current pmap & pmap exists. * 2. Not wired. * 3. Read access. * 4. No page table pages. * 5. Tlbflush is deferred to calling procedure. * 6. Page IS managed. * but is *MUCH* faster than pmap_enter... */ static vm_page_t pmap_enter_quick(pmap_t pmap, vm_offset_t va, vm_page_t m, vm_page_t mpte) { unsigned *pte; vm_paddr_t pa; pmap_inval_info info; pmap_inval_init(&info); /* * In the case that a page table page is not * resident, we are creating it here. */ if (va < UPT_MIN_ADDRESS) { unsigned ptepindex; vm_offset_t ptepa; /* * Calculate pagetable page index */ ptepindex = va >> PDRSHIFT; if (mpte && (mpte->pindex == ptepindex)) { mpte->hold_count++; } else { retry: /* * Get the page directory entry */ ptepa = (vm_offset_t) pmap->pm_pdir[ptepindex]; /* * If the page table page is mapped, we just increment * the hold count, and activate it. */ if (ptepa) { if (ptepa & PG_PS) panic("pmap_enter_quick: unexpected mapping into 4MB page"); if (pmap->pm_ptphint && (pmap->pm_ptphint->pindex == ptepindex)) { mpte = pmap->pm_ptphint; } else { mpte = pmap_page_lookup( pmap->pm_pteobj, ptepindex); pmap->pm_ptphint = mpte; } if (mpte == NULL) goto retry; mpte->hold_count++; } else { mpte = _pmap_allocpte(pmap, ptepindex); } } } else { mpte = NULL; } /* * This call to vtopte makes the assumption that we are * entering the page into the current pmap. In order to support * quick entry into any pmap, one would likely use pmap_pte_quick. * But that isn't as quick as vtopte. */ pte = (unsigned *)vtopte(va); if (*pte) { if (mpte) pmap_unwire_pte_hold(pmap, mpte, &info); return 0; } /* * Enter on the PV list if part of our managed memory. Note that we * raise IPL while manipulating pv_table since pmap_enter can be * called at interrupt time. */ if ((m->flags & (PG_FICTITIOUS|PG_UNMANAGED)) == 0) pmap_insert_entry(pmap, va, mpte, m); /* * Increment counters */ pmap->pm_stats.resident_count++; pa = VM_PAGE_TO_PHYS(m); /* * Now validate mapping with RO protection */ if (m->flags & (PG_FICTITIOUS|PG_UNMANAGED)) *pte = pa | PG_V | PG_U; else *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) { pmap_kenter((vm_offset_t)crashdumpmap + (i * PAGE_SIZE), pa); return ((void *)crashdumpmap); } #define MAX_INIT_PT (96) /* * This routine preloads the ptes for a given object into the specified pmap. * This eliminates the blast of soft faults on process startup and * immediately after an mmap. */ void pmap_object_init_pt(pmap_t pmap, vm_offset_t addr, vm_prot_t prot, vm_object_t object, vm_pindex_t pindex, vm_size_t size, int limit) { vm_offset_t tmpidx; int psize; vm_page_t p, mpte; int objpgs; int s; if ((prot & VM_PROT_READ) == 0 || pmap == NULL || object == NULL) return; #if 0 /* * XXX you must be joking, entering PTE's into a user page table * without any accounting? This could result in the page table * being freed while it still contains mappings (free with PG_ZERO * assumption leading to a non-zero page being marked PG_ZERO). */ /* * This code maps large physical mmap regions into the * processor address space. Note that some shortcuts * are taken, but the code works. */ if (pseflag && (object->type == OBJT_DEVICE) && ((addr & (NBPDR - 1)) == 0) && ((size & (NBPDR - 1)) == 0) ) { int i; vm_page_t m[1]; unsigned int ptepindex; int npdes; vm_offset_t ptepa; if (pmap->pm_pdir[ptepindex = (addr >> PDRSHIFT)]) return; retry: p = vm_page_lookup(object, pindex); if (p && vm_page_sleep_busy(p, FALSE, "init4p")) goto retry; if (p == NULL) { p = vm_page_alloc(object, pindex, VM_ALLOC_NORMAL); if (p == NULL) return; m[0] = p; if (vm_pager_get_pages(object, m, 1, 0) != VM_PAGER_OK) { vm_page_free(p); return; } p = vm_page_lookup(object, pindex); vm_page_wakeup(p); } ptepa = (vm_offset_t) VM_PAGE_TO_PHYS(p); if (ptepa & (NBPDR - 1)) { return; } p->valid = VM_PAGE_BITS_ALL; pmap->pm_stats.resident_count += size >> PAGE_SHIFT; npdes = size >> PDRSHIFT; for (i = 0; i < npdes; i++) { pmap->pm_pdir[ptepindex] = (pd_entry_t) (ptepa | PG_U | PG_RW | PG_V | PG_PS); ptepa += NBPDR; ptepindex += 1; } vm_page_flag_set(p, PG_MAPPED); cpu_invltlb(); smp_invltlb(); return; } #endif psize = i386_btop(size); if ((object->type != OBJT_VNODE) || ((limit & MAP_PREFAULT_PARTIAL) && (psize > MAX_INIT_PT) && (object->resident_page_count > MAX_INIT_PT))) { return; } if (psize + pindex > object->size) { if (object->size < pindex) return; psize = object->size - pindex; } /* * If we are processing a major portion of the object, then scan the * entire thing. * * We cannot safely scan the object's memq unless we are at splvm(), * since interrupts can remove pages from objects. */ s = splvm(); mpte = NULL; if (psize > (object->resident_page_count >> 2)) { objpgs = psize; for (p = TAILQ_FIRST(&object->memq); objpgs > 0 && p != NULL; p = TAILQ_NEXT(p, listq) ) { tmpidx = p->pindex; if (tmpidx < pindex) continue; tmpidx -= pindex; if (tmpidx >= psize) continue; /* * don't allow an madvise to blow away our really * free pages allocating pv entries. */ if ((limit & MAP_PREFAULT_MADVISE) && vmstats.v_free_count < vmstats.v_free_reserved) { break; } if (((p->valid & VM_PAGE_BITS_ALL) == VM_PAGE_BITS_ALL) && (p->busy == 0) && (p->flags & (PG_BUSY | PG_FICTITIOUS)) == 0) { if ((p->queue - p->pc) == PQ_CACHE) vm_page_deactivate(p); vm_page_busy(p); mpte = pmap_enter_quick(pmap, addr + i386_ptob(tmpidx), p, mpte); vm_page_flag_set(p, PG_MAPPED); vm_page_wakeup(p); } objpgs -= 1; } } else { /* * else lookup the pages one-by-one. */ for (tmpidx = 0; tmpidx < psize; tmpidx += 1) { /* * don't allow an madvise to blow away our really * free pages allocating pv entries. */ if ((limit & MAP_PREFAULT_MADVISE) && vmstats.v_free_count < vmstats.v_free_reserved) { break; } p = vm_page_lookup(object, tmpidx + pindex); if (p && ((p->valid & VM_PAGE_BITS_ALL) == VM_PAGE_BITS_ALL) && (p->busy == 0) && (p->flags & (PG_BUSY | PG_FICTITIOUS)) == 0) { if ((p->queue - p->pc) == PQ_CACHE) vm_page_deactivate(p); vm_page_busy(p); mpte = pmap_enter_quick(pmap, addr + i386_ptob(tmpidx), p, mpte); vm_page_flag_set(p, PG_MAPPED); vm_page_wakeup(p); } } } splx(s); } /* * pmap_prefault provides a quick way of clustering pagefaults into a * processes address space. It is a "cousin" of pmap_object_init_pt, * except it runs at page fault time instead of mmap time. */ #define PFBAK 4 #define PFFOR 4 #define PAGEORDER_SIZE (PFBAK+PFFOR) static int pmap_prefault_pageorder[] = { -PAGE_SIZE, PAGE_SIZE, -2 * PAGE_SIZE, 2 * PAGE_SIZE, -3 * PAGE_SIZE, 3 * PAGE_SIZE -4 * PAGE_SIZE, 4 * PAGE_SIZE }; void pmap_prefault(pmap_t pmap, vm_offset_t addra, vm_map_entry_t entry) { int i; int s; vm_offset_t starta; vm_offset_t addr; vm_pindex_t pindex; vm_page_t m, mpte; vm_object_t object; if (!curproc || (pmap != vmspace_pmap(curproc->p_vmspace))) return; object = entry->object.vm_object; starta = addra - PFBAK * PAGE_SIZE; if (starta < entry->start) starta = entry->start; else if (starta > addra) starta = 0; /* * splvm() protection is required to maintain the page/object * association, interrupts can free pages and remove them from * their objects. */ mpte = NULL; s = splvm(); for (i = 0; i < PAGEORDER_SIZE; i++) { vm_object_t lobject; unsigned *pte; addr = addra + pmap_prefault_pageorder[i]; if (addr > addra + (PFFOR * PAGE_SIZE)) addr = 0; if (addr < starta || addr >= entry->end) continue; if ((*pmap_pde(pmap, addr)) == NULL) continue; pte = (unsigned *) vtopte(addr); if (*pte) continue; pindex = ((addr - entry->start) + entry->offset) >> PAGE_SHIFT; lobject = object; for (m = vm_page_lookup(lobject, pindex); (!m && (lobject->type == OBJT_DEFAULT) && (lobject->backing_object)); lobject = lobject->backing_object ) { if (lobject->backing_object_offset & PAGE_MASK) break; pindex += (lobject->backing_object_offset >> PAGE_SHIFT); m = vm_page_lookup(lobject->backing_object, pindex); } /* * give-up when a page is not in memory */ if (m == NULL) break; if (((m->valid & VM_PAGE_BITS_ALL) == VM_PAGE_BITS_ALL) && (m->busy == 0) && (m->flags & (PG_BUSY | PG_FICTITIOUS)) == 0) { if ((m->queue - m->pc) == PQ_CACHE) { vm_page_deactivate(m); } vm_page_busy(m); mpte = pmap_enter_quick(pmap, addr, m, mpte); vm_page_flag_set(m, PG_MAPPED); vm_page_wakeup(m); } } splx(s); } /* * 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) { unsigned *pte; if (pmap == NULL) return; pte = pmap_pte(pmap, va); if (wired && !pmap_pte_w(pte)) pmap->pm_stats.wired_count++; else if (!wired && pmap_pte_w(pte)) pmap->pm_stats.wired_count--; /* * Wiring is not a hardware characteristic so there is no need to * invalidate TLB. However, in an SMP environment we must use * a locked bus cycle to update the pte (if we are not using * the pmap_inval_*() API that is)... it's ok to do this for simple * wiring changes. */ #ifdef SMP if (wired) atomic_set_int(pte, PG_W); else atomic_clear_int(pte, PG_W); #else if (wired) atomic_set_int_nonlocked(pte, PG_W); else atomic_clear_int_nonlocked(pte, PG_W); #endif } /* * 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) { pmap_inval_info info; vm_offset_t addr; vm_offset_t end_addr = src_addr + len; vm_offset_t pdnxt; unsigned src_frame, dst_frame; vm_page_t m; int s; if (dst_addr != src_addr) return; src_frame = ((unsigned) src_pmap->pm_pdir[PTDPTDI]) & PG_FRAME; if (src_frame != (((unsigned) PTDpde) & PG_FRAME)) { return; } dst_frame = ((unsigned) dst_pmap->pm_pdir[PTDPTDI]) & PG_FRAME; if (dst_frame != (((unsigned) APTDpde) & PG_FRAME)) { APTDpde = (pd_entry_t) (dst_frame | PG_RW | PG_V); /* The page directory is not shared between CPUs */ cpu_invltlb(); } pmap_inval_init(&info); pmap_inval_add(&info, dst_pmap, -1); pmap_inval_add(&info, src_pmap, -1); /* * splvm() protection is required to maintain the page/object * association, interrupts can free pages and remove them from * their objects. */ s = splvm(); for (addr = src_addr; addr < end_addr; addr = pdnxt) { unsigned *src_pte, *dst_pte; vm_page_t dstmpte, srcmpte; vm_offset_t srcptepaddr; unsigned ptepindex; if (addr >= UPT_MIN_ADDRESS) panic("pmap_copy: invalid to pmap_copy page tables\n"); /* * Don't let optional prefaulting of pages make us go * way below the low water mark of free pages or way * above high water mark of used pv entries. */ if (vmstats.v_free_count < vmstats.v_free_reserved || pv_entry_count > pv_entry_high_water) break; pdnxt = ((addr + PAGE_SIZE*NPTEPG) & ~(PAGE_SIZE*NPTEPG - 1)); ptepindex = addr >> PDRSHIFT; srcptepaddr = (vm_offset_t) src_pmap->pm_pdir[ptepindex]; if (srcptepaddr == 0) continue; if (srcptepaddr & PG_PS) { if (dst_pmap->pm_pdir[ptepindex] == 0) { dst_pmap->pm_pdir[ptepindex] = (pd_entry_t) srcptepaddr; dst_pmap->pm_stats.resident_count += NBPDR / PAGE_SIZE; } continue; } srcmpte = vm_page_lookup(src_pmap->pm_pteobj, ptepindex); if ((srcmpte == NULL) || (srcmpte->hold_count == 0) || (srcmpte->flags & PG_BUSY)) continue; if (pdnxt > end_addr) pdnxt = end_addr; src_pte = (unsigned *) vtopte(addr); dst_pte = (unsigned *) avtopte(addr); while (addr < pdnxt) { unsigned ptetemp; ptetemp = *src_pte; /* * we only virtual copy managed pages */ if ((ptetemp & PG_MANAGED) != 0) { /* * We have to check after allocpte for the * pte still being around... allocpte can * block. */ dstmpte = pmap_allocpte(dst_pmap, addr); if ((*dst_pte == 0) && (ptetemp = *src_pte)) { /* * Clear the modified and * accessed (referenced) bits * during the copy. */ m = PHYS_TO_VM_PAGE(ptetemp); *dst_pte = ptetemp & ~(PG_M | PG_A); dst_pmap->pm_stats.resident_count++; pmap_insert_entry(dst_pmap, addr, dstmpte, m); } else { pmap_unwire_pte_hold(dst_pmap, dstmpte, &info); } if (dstmpte->hold_count >= srcmpte->hold_count) break; } addr += PAGE_SIZE; src_pte++; dst_pte++; } } splx(s); pmap_inval_flush(&info); } /* * Routine: pmap_kernel * Function: * Returns the physical map handle for the kernel. */ pmap_t pmap_kernel(void) { return (kernel_pmap); } /* * pmap_zero_page: * * Zero the specified PA by mapping the page into KVM and clearing its * contents. * * This function may be called from an interrupt and no locking is * required. */ void pmap_zero_page(vm_paddr_t phys) { struct mdglobaldata *gd = mdcpu; crit_enter(); if (*(int *)gd->gd_CMAP3) panic("pmap_zero_page: CMAP3 busy"); *(int *)gd->gd_CMAP3 = PG_V | PG_RW | (phys & PG_FRAME) | PG_A | PG_M; cpu_invlpg(gd->gd_CADDR3); #if defined(I686_CPU) if (cpu_class == CPUCLASS_686) i686_pagezero(gd->gd_CADDR3); else #endif bzero(gd->gd_CADDR3, PAGE_SIZE); *(int *) gd->gd_CMAP3 = 0; crit_exit(); } /* * pmap_page_assertzero: * * Assert that a page is empty, panic if it isn't. */ void pmap_page_assertzero(vm_paddr_t phys) { struct mdglobaldata *gd = mdcpu; int i; crit_enter(); if (*(int *)gd->gd_CMAP3) panic("pmap_zero_page: CMAP3 busy"); *(int *)gd->gd_CMAP3 = PG_V | PG_RW | (phys & PG_FRAME) | PG_A | PG_M; cpu_invlpg(gd->gd_CADDR3); for (i = 0; i < PAGE_SIZE; i += 4) { if (*(int *)((char *)gd->gd_CADDR3 + i) != 0) { panic("pmap_page_assertzero() @ %p not zero!\n", (void *)gd->gd_CADDR3); } } *(int *) gd->gd_CMAP3 = 0; crit_exit(); } /* * pmap_zero_page: * * Zero part of a physical page by mapping it into memory and clearing * its contents with bzero. * * off and size may not cover an area beyond a single hardware page. */ void pmap_zero_page_area(vm_paddr_t phys, int off, int size) { struct mdglobaldata *gd = mdcpu; crit_enter(); if (*(int *) gd->gd_CMAP3) panic("pmap_zero_page: CMAP3 busy"); *(int *) gd->gd_CMAP3 = PG_V | PG_RW | (phys & PG_FRAME) | PG_A | PG_M; cpu_invlpg(gd->gd_CADDR3); #if defined(I686_CPU) if (cpu_class == CPUCLASS_686 && off == 0 && size == PAGE_SIZE) i686_pagezero(gd->gd_CADDR3); else #endif bzero((char *)gd->gd_CADDR3 + off, size); *(int *) gd->gd_CMAP3 = 0; crit_exit(); } /* * pmap_copy_page: * * Copy the physical page from the source PA to the target PA. * This function may be called from an interrupt. No locking * is required. */ void pmap_copy_page(vm_paddr_t src, vm_paddr_t dst) { struct mdglobaldata *gd = mdcpu; crit_enter(); if (*(int *) gd->gd_CMAP1) panic("pmap_copy_page: CMAP1 busy"); if (*(int *) gd->gd_CMAP2) panic("pmap_copy_page: CMAP2 busy"); *(int *) gd->gd_CMAP1 = PG_V | (src & PG_FRAME) | PG_A; *(int *) gd->gd_CMAP2 = PG_V | PG_RW | (dst & PG_FRAME) | PG_A | PG_M; cpu_invlpg(gd->gd_CADDR1); cpu_invlpg(gd->gd_CADDR2); bcopy(gd->gd_CADDR1, gd->gd_CADDR2, PAGE_SIZE); *(int *) gd->gd_CMAP1 = 0; *(int *) gd->gd_CMAP2 = 0; crit_exit(); } /* * pmap_copy_page_frag: * * Copy the physical page from the source PA to the target PA. * This function may be called from an interrupt. No locking * is required. */ void pmap_copy_page_frag(vm_paddr_t src, vm_paddr_t dst, size_t bytes) { struct mdglobaldata *gd = mdcpu; crit_enter(); if (*(int *) gd->gd_CMAP1) panic("pmap_copy_page: CMAP1 busy"); if (*(int *) gd->gd_CMAP2) panic("pmap_copy_page: CMAP2 busy"); *(int *) gd->gd_CMAP1 = PG_V | (src & PG_FRAME) | PG_A; *(int *) gd->gd_CMAP2 = PG_V | PG_RW | (dst & PG_FRAME) | PG_A | PG_M; cpu_invlpg(gd->gd_CADDR1); cpu_invlpg(gd->gd_CADDR2); bcopy((char *)gd->gd_CADDR1 + (src & PAGE_MASK), (char *)gd->gd_CADDR2 + (dst & PAGE_MASK), bytes); *(int *) gd->gd_CMAP1 = 0; *(int *) gd->gd_CMAP2 = 0; crit_exit(); } /* * Routine: pmap_pageable * Function: * Make the specified pages (by pmap, offset) * pageable (or not) as requested. * * A page which is not pageable may not take * a fault; therefore, its page table entry * must remain valid for the duration. * * This routine is merely advisory; pmap_enter * will specify that these pages are to be wired * down (or not) as appropriate. */ void pmap_pageable(pmap_t pmap, vm_offset_t sva, vm_offset_t eva, boolean_t pageable) { } /* * 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) { pv_entry_t pv; int loops = 0; int s; if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) return FALSE; s = splvm(); TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) { if (pv->pv_pmap == pmap) { splx(s); return TRUE; } loops++; if (loops >= 16) break; } splx(s); return (FALSE); } #define PMAP_REMOVE_PAGES_CURPROC_ONLY /* * 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, vm_offset_t sva, vm_offset_t eva) { unsigned *pte, tpte; pv_entry_t pv, npv; int s; vm_page_t m; pmap_inval_info info; #ifdef PMAP_REMOVE_PAGES_CURPROC_ONLY if (!curproc || (pmap != vmspace_pmap(curproc->p_vmspace))) { printf("warning: pmap_remove_pages called with non-current pmap\n"); return; } #endif pmap_inval_init(&info); s = splvm(); for(pv = TAILQ_FIRST(&pmap->pm_pvlist); pv; pv = npv) { if (pv->pv_va >= eva || pv->pv_va < sva) { npv = TAILQ_NEXT(pv, pv_plist); continue; } #ifdef PMAP_REMOVE_PAGES_CURPROC_ONLY pte = (unsigned *)vtopte(pv->pv_va); #else pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va); #endif pmap_inval_add(&info, pv->pv_pmap, pv->pv_va); tpte = *pte; /* * We cannot remove wired pages from a process' mapping at this time */ if (tpte & PG_W) { npv = TAILQ_NEXT(pv, pv_plist); continue; } *pte = 0; m = PHYS_TO_VM_PAGE(tpte); KASSERT(m < &vm_page_array[vm_page_array_size], ("pmap_remove_pages: bad tpte %x", tpte)); pv->pv_pmap->pm_stats.resident_count--; /* * Update the vm_page_t clean and reference bits. */ if (tpte & PG_M) { vm_page_dirty(m); } npv = TAILQ_NEXT(pv, pv_plist); TAILQ_REMOVE(&pv->pv_pmap->pm_pvlist, pv, pv_plist); m->md.pv_list_count--; TAILQ_REMOVE(&m->md.pv_list, pv, pv_list); if (TAILQ_FIRST(&m->md.pv_list) == NULL) { vm_page_flag_clear(m, PG_MAPPED | PG_WRITEABLE); } pmap_unuse_pt(pv->pv_pmap, pv->pv_va, pv->pv_ptem, &info); free_pv_entry(pv); } pmap_inval_flush(&info); splx(s); } /* * pmap_testbit tests bits in pte's * note that the testbit/changebit routines are inline, * and a lot of things compile-time evaluate. */ static boolean_t pmap_testbit(vm_page_t m, int bit) { pv_entry_t pv; unsigned *pte; int s; if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) return FALSE; if (TAILQ_FIRST(&m->md.pv_list) == NULL) return FALSE; s = splvm(); TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) { /* * if the bit being tested is the modified bit, then * mark clean_map and ptes as never * modified. */ if (bit & (PG_A|PG_M)) { if (!pmap_track_modified(pv->pv_va)) continue; } #if defined(PMAP_DIAGNOSTIC) if (!pv->pv_pmap) { printf("Null pmap (tb) at va: 0x%x\n", pv->pv_va); continue; } #endif pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va); if (*pte & bit) { splx(s); return TRUE; } } splx(s); return (FALSE); } /* * this routine is used to modify bits in ptes */ static __inline void pmap_changebit(vm_page_t m, int bit, boolean_t setem) { struct pmap_inval_info info; pv_entry_t pv; unsigned *pte; int s; if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) return; pmap_inval_init(&info); s = splvm(); /* * Loop over all current mappings setting/clearing as appropos If * setting RO do we need to clear the VAC? */ TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) { /* * don't write protect pager mappings */ if (!setem && (bit == PG_RW)) { if (!pmap_track_modified(pv->pv_va)) continue; } #if defined(PMAP_DIAGNOSTIC) if (!pv->pv_pmap) { printf("Null pmap (cb) at va: 0x%x\n", pv->pv_va); continue; } #endif /* * Careful here. We can use a locked bus instruction to * clear PG_A or PG_M safely but we need to synchronize * with the target cpus when we mess with PG_RW. */ pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va); if (bit == PG_RW) pmap_inval_add(&info, pv->pv_pmap, pv->pv_va); if (setem) { #ifdef SMP atomic_set_int(pte, bit); #else atomic_set_int_nonlocked(pte, bit); #endif } else { vm_offset_t pbits = *(vm_offset_t *)pte; if (pbits & bit) { if (bit == PG_RW) { if (pbits & PG_M) { vm_page_dirty(m); } #ifdef SMP atomic_clear_int(pte, PG_M|PG_RW); #else atomic_clear_int_nonlocked(pte, PG_M|PG_RW); #endif } else { #ifdef SMP atomic_clear_int(pte, bit); #else atomic_clear_int_nonlocked(pte, bit); #endif } } } } pmap_inval_flush(&info); splx(s); } /* * pmap_page_protect: * * Lower the permission for all mappings to a given page. */ void pmap_page_protect(vm_page_t m, vm_prot_t prot) { if ((prot & VM_PROT_WRITE) == 0) { if (prot & (VM_PROT_READ | VM_PROT_EXECUTE)) { pmap_changebit(m, PG_RW, FALSE); } else { pmap_remove_all(m); } } } vm_paddr_t pmap_phys_address(int ppn) { return (i386_ptob(ppn)); } /* * 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) { pv_entry_t pv, pvf, pvn; unsigned *pte; int s; int rtval = 0; if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) return (rtval); s = splvm(); 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); if (!pmap_track_modified(pv->pv_va)) continue; pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va); if (pte && (*pte & PG_A)) { #ifdef SMP atomic_clear_int(pte, PG_A); #else atomic_clear_int_nonlocked(pte, PG_A); #endif rtval++; if (rtval > 4) { break; } } } while ((pv = pvn) != NULL && pv != pvf); } splx(s); return (rtval); } /* * 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) { return pmap_testbit(m, PG_M); } /* * Clear the modify bits on the specified physical page. */ void pmap_clear_modify(vm_page_t m) { pmap_changebit(m, PG_M, FALSE); } /* * pmap_clear_reference: * * Clear the reference bit on the specified physical page. */ void pmap_clear_reference(vm_page_t m) { pmap_changebit(m, PG_A, FALSE); } /* * Miscellaneous support routines follow */ static void i386_protection_init(void) { int *kp, prot; kp = protection_codes; for (prot = 0; prot < 8; prot++) { switch (prot) { case VM_PROT_NONE | VM_PROT_NONE | VM_PROT_NONE: /* * Read access is also 0. There isn't any execute bit, * so just make it readable. */ case VM_PROT_READ | VM_PROT_NONE | VM_PROT_NONE: case VM_PROT_READ | VM_PROT_NONE | VM_PROT_EXECUTE: case VM_PROT_NONE | VM_PROT_NONE | VM_PROT_EXECUTE: *kp++ = 0; break; case VM_PROT_NONE | VM_PROT_WRITE | VM_PROT_NONE: case VM_PROT_NONE | VM_PROT_WRITE | VM_PROT_EXECUTE: case VM_PROT_READ | VM_PROT_WRITE | VM_PROT_NONE: case VM_PROT_READ | VM_PROT_WRITE | VM_PROT_EXECUTE: *kp++ = PG_RW; break; } } } /* * 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. * * NOTE: we can't use pgeflag unless we invalidate the pages one at * a time. */ void * pmap_mapdev(vm_paddr_t pa, vm_size_t size) { vm_offset_t va, tmpva, offset; unsigned *pte; 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 = pa & PG_FRAME; for (tmpva = va; size > 0;) { pte = (unsigned *)vtopte(tmpva); *pte = pa | PG_RW | PG_V; /* | pgeflag; */ size -= PAGE_SIZE; tmpva += PAGE_SIZE; pa += PAGE_SIZE; } cpu_invltlb(); smp_invltlb(); return ((void *)(va + offset)); } void pmap_unmapdev(vm_offset_t va, vm_size_t size) { vm_offset_t base, offset; base = va & PG_FRAME; offset = va & PAGE_MASK; size = roundup(offset + size, PAGE_SIZE); pmap_qremove(va, size >> PAGE_SHIFT); kmem_free(kernel_map, base, size); } /* * perform the pmap work for mincore */ int pmap_mincore(pmap_t pmap, vm_offset_t addr) { unsigned *ptep, pte; vm_page_t m; int val = 0; ptep = pmap_pte(pmap, addr); if (ptep == 0) { return 0; } if ((pte = *ptep) != 0) { vm_offset_t pa; val = MINCORE_INCORE; if ((pte & PG_MANAGED) == 0) return val; pa = pte & PG_FRAME; m = PHYS_TO_VM_PAGE(pa); /* * Modified by us */ if (pte & PG_M) val |= MINCORE_MODIFIED|MINCORE_MODIFIED_OTHER; /* * Modified by someone */ else if (m->dirty || pmap_is_modified(m)) val |= MINCORE_MODIFIED_OTHER; /* * Referenced by us */ if (pte & PG_A) val |= MINCORE_REFERENCED|MINCORE_REFERENCED_OTHER; /* * Referenced by someone */ else if ((m->flags & PG_REFERENCED) || pmap_ts_referenced(m)) { val |= MINCORE_REFERENCED_OTHER; vm_page_flag_set(m, PG_REFERENCED); } } return val; } void pmap_activate(struct proc *p) { pmap_t pmap; pmap = vmspace_pmap(p->p_vmspace); #if defined(SMP) atomic_set_int(&pmap->pm_active, 1 << mycpu->gd_cpuid); #else pmap->pm_active |= 1; #endif #if defined(SWTCH_OPTIM_STATS) tlb_flush_count++; #endif p->p_thread->td_pcb->pcb_cr3 = vtophys(pmap->pm_pdir); load_cr3(p->p_thread->td_pcb->pcb_cr3); } vm_offset_t pmap_addr_hint(vm_object_t obj, vm_offset_t addr, vm_size_t size) { if ((obj == NULL) || (size < NBPDR) || (obj->type != OBJT_DEVICE)) { return addr; } addr = (addr + (NBPDR - 1)) & ~(NBPDR - 1); return addr; } #if defined(PMAP_DEBUG) int pmap_pid_dump(int pid) { pmap_t pmap; struct proc *p; int npte = 0; int index; FOREACH_PROC_IN_SYSTEM(p) { if (p->p_pid != pid) continue; if (p->p_vmspace) { int i,j; index = 0; pmap = vmspace_pmap(p->p_vmspace); for(i=0;i<1024;i++) { pd_entry_t *pde; unsigned *pte; unsigned base = i << PDRSHIFT; pde = &pmap->pm_pdir[i]; if (pde && pmap_pde_v(pde)) { for(j=0;j<1024;j++) { unsigned va = base + (j << PAGE_SHIFT); if (va >= (vm_offset_t) VM_MIN_KERNEL_ADDRESS) { if (index) { index = 0; printf("\n"); } return npte; } pte = pmap_pte_quick( pmap, va); if (pte && pmap_pte_v(pte)) { vm_offset_t pa; vm_page_t m; pa = *(int *)pte; m = PHYS_TO_VM_PAGE(pa); printf("va: 0x%x, pt: 0x%x, h: %d, w: %d, f: 0x%x", va, pa, m->hold_count, m->wire_count, m->flags); npte++; index++; if (index >= 2) { index = 0; printf("\n"); } else { printf(" "); } } } } } } } return npte; } #endif #if defined(DEBUG) static void pads (pmap_t pm); void pmap_pvdump (vm_paddr_t pa); /* print address space of pmap*/ static void pads(pmap_t pm) { unsigned va, i, j; unsigned *ptep; if (pm == kernel_pmap) return; for (i = 0; i < 1024; i++) if (pm->pm_pdir[i]) for (j = 0; j < 1024; j++) { va = (i << PDRSHIFT) + (j << PAGE_SHIFT); if (pm == kernel_pmap && va < KERNBASE) continue; if (pm != kernel_pmap && va > UPT_MAX_ADDRESS) continue; ptep = pmap_pte_quick(pm, va); if (pmap_pte_v(ptep)) printf("%x:%x ", va, *(int *) ptep); }; } void pmap_pvdump(vm_paddr_t pa) { pv_entry_t pv; vm_page_t m; printf("pa %08llx", (long long)pa); m = PHYS_TO_VM_PAGE(pa); TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) { #ifdef used_to_be printf(" -> pmap %p, va %x, flags %x", (void *)pv->pv_pmap, pv->pv_va, pv->pv_flags); #endif printf(" -> pmap %p, va %x", (void *)pv->pv_pmap, pv->pv_va); pads(pv->pv_pmap); } printf(" "); } #endif