/* * 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 * $FreeBSD$ */ /* * 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_msgbuf.h" #include "opt_kstack_pages.h" #include #include #include #include #include #include #include #include #include #include #include #include #ifdef SMP #include #endif #include #include #include #include #include #include #include #include #include #include #include #include #include #include #if defined(SMP) || defined(APIC_IO) #include #include #include #include #endif /* SMP || APIC_IO */ #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) #define pmap_pte_set_w(pte, v) ((v)?(*(int *)pte |= PG_W):(*(int *)pte &= ~PG_W)) #define pmap_pte_set_prot(pte, v) ((*(int *)pte &= ~PG_PROT), (*(int *)pte |= (v))) /* * 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]; struct pmap kernel_pmap_store; LIST_HEAD(pmaplist, pmap); struct pmaplist allpmaps; vm_offset_t avail_start; /* PA of first available physical page */ vm_offset_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; extern u_int32_t KERNend; /* * Data for the pv entry allocation mechanism */ static uma_zone_t pvzone; 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; /* * All those kernel PT submaps that BSD is so fond of */ pt_entry_t *CMAP1 = 0; static pt_entry_t *CMAP2, *CMAP3, *ptmmap; caddr_t CADDR1 = 0, ptvmmap = 0; static caddr_t CADDR2, CADDR3; static pt_entry_t *msgbufmap; struct msgbuf *msgbufp = 0; /* * Crashdump maps. */ static pt_entry_t *pt_crashdumpmap; static caddr_t crashdumpmap; #ifdef SMP extern pt_entry_t *SMPpt; #endif static pt_entry_t *PMAP1 = 0; static pt_entry_t *PADDR1 = 0; static PMAP_INLINE void free_pv_entry(pv_entry_t pv); static pt_entry_t *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(pmap_t pmap, pt_entry_t *ptq, vm_offset_t sva); static void pmap_remove_page(struct pmap *pmap, vm_offset_t va); static int pmap_remove_entry(struct pmap *pmap, vm_page_t m, vm_offset_t va); 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 pt_entry_t *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); static vm_offset_t pmap_kmem_choose(vm_offset_t addr); static void *pmap_allocf(uma_zone_t zone, int bytes, u_int8_t *flags, int wait); static pd_entry_t pdir4mb; /* * Routine: pmap_pte * Function: * Extract the page table entry associated * with the given map/virtual_address pair. */ PMAP_INLINE pt_entry_t * pmap_pte(pmap, va) register pmap_t pmap; vm_offset_t va; { pd_entry_t *pdeaddr; if (pmap) { pdeaddr = pmap_pde(pmap, va); if (*pdeaddr & PG_PS) return pdeaddr; if (*pdeaddr) { return get_ptbase(pmap) + i386_btop(va); } } return (0); } /* * 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; } /* * 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_offset_t firstaddr; vm_offset_t loadaddr; { vm_offset_t va; pt_entry_t *pte; 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(); /* * Initialize the kernel pmap (which is statically allocated). */ kernel_pmap->pm_pdir = (pd_entry_t *) (KERNBASE + (u_int)IdlePTD); kernel_pmap->pm_active = -1; /* don't allow deactivation */ TAILQ_INIT(&kernel_pmap->pm_pvlist); LIST_INIT(&allpmaps); LIST_INSERT_HEAD(&allpmaps, kernel_pmap, pm_list); 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. * CMAP3 is used for the idle process page zeroing. */ SYSMAP(caddr_t, CMAP1, CADDR1, 1) SYSMAP(caddr_t, CMAP2, CADDR2, 1) SYSMAP(caddr_t, CMAP3, CADDR3, 1) /* * Crashdump maps. */ SYSMAP(caddr_t, pt_crashdumpmap, crashdumpmap, MAXDUMPPGS); /* * ptvmmap is used for reading arbitrary physical pages via /dev/mem. * XXX ptmmap is not used. */ 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))) /* * ptemap is used for pmap_pte_quick */ SYSMAP(pt_entry_t *, PMAP1, PADDR1, 1); virtual_avail = va; *CMAP1 = *CMAP2 = 0; for (i = 0; i < NKPT; i++) PTD[i] = 0; pgeflag = 0; #ifndef DISABLE_PG_G 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; #ifndef DISABLE_PSE if (cpu_feature & CPUID_PSE) { pd_entry_t ptditmp; /* * Note that we have enabled PSE mode */ pseflag = PG_PS; ptditmp = *(PTmap + i386_btop(KERNBASE)); ptditmp &= ~(NBPDR - 1); ptditmp |= PG_V | PG_RW | PG_PS | PG_U | pgeflag; pdir4mb = ptditmp; } #endif #ifndef SMP /* * Turn on PGE/PSE. SMP does this later on since the * 4K page tables are required for AP boot (for now). * XXX fixme. */ pmap_set_opt(); #endif #ifdef SMP if (cpu_apic_address == 0) panic("pmap_bootstrap: no local apic! (non-SMP hardware?)"); /* 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 invltlb(); } /* * Enable 4MB page mode for MP startup. Turn on PG_G support. * BSP will run this after all the AP's have started up. */ void pmap_set_opt(void) { pt_entry_t *pte; vm_offset_t va, endva; if (pgeflag && (cpu_feature & CPUID_PGE)) { load_cr4(rcr4() | CR4_PGE); invltlb(); /* Insurance */ } #ifndef DISABLE_PSE if (pseflag && (cpu_feature & CPUID_PSE)) { load_cr4(rcr4() | CR4_PSE); invltlb(); /* Insurance */ } #endif if (PCPU_GET(cpuid) == 0) { #ifndef DISABLE_PSE if (pdir4mb) { kernel_pmap->pm_pdir[KPTDI] = PTD[KPTDI] = pdir4mb; invltlb(); /* Insurance */ } #endif if (pgeflag) { /* Turn on PG_G for text, data, bss pages. */ va = (vm_offset_t)btext; #ifndef DISABLE_PSE if (pseflag && (cpu_feature & CPUID_PSE)) { if (va < KERNBASE + (1 << PDRSHIFT)) va = KERNBASE + (1 << PDRSHIFT); } #endif endva = KERNBASE + KERNend; while (va < endva) { pte = vtopte(va); if (*pte) *pte |= pgeflag; va += PAGE_SIZE; } invltlb(); /* Insurance */ } /* * We do not need to broadcast the invltlb here, because * each AP does it the moment it is released from the boot * lock. See ap_init(). */ } } void * pmap_allocf(uma_zone_t zone, int bytes, u_int8_t *flags, int wait) { *flags = UMA_SLAB_PRIV; return (void *)kmem_alloc(kernel_map, bytes); } /* * 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_offset_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 = uma_zcreate("PV ENTRY", sizeof (struct pv_entry), NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, UMA_ZONE_VM); uma_zone_set_allocf(pvzone, pmap_allocf); uma_prealloc(pvzone, initial_pvs); /* * 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); uma_zone_set_obj(pvzone, &pvzone_obj, pv_entry_max); } /*************************************************** * 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 < kmi.clean_sva) || (va >= kmi.clean_eva)) return 1; else return 0; } #ifdef I386_CPU /* * i386 only has "invalidate everything" and no SMP to worry about. */ PMAP_INLINE void pmap_invalidate_page(pmap_t pmap, vm_offset_t va) { if (pmap == kernel_pmap || pmap->pm_active) invltlb(); } PMAP_INLINE void pmap_invalidate_range(pmap_t pmap, vm_offset_t sva, vm_offset_t eva) { if (pmap == kernel_pmap || pmap->pm_active) invltlb(); } PMAP_INLINE void pmap_invalidate_all(pmap_t pmap) { if (pmap == kernel_pmap || pmap->pm_active) invltlb(); } #else /* !I386_CPU */ #ifdef SMP /* * For SMP, these functions have to use the IPI mechanism for coherence. */ void pmap_invalidate_page(pmap_t pmap, vm_offset_t va) { u_int cpumask; u_int other_cpus; critical_enter(); /* * We need to disable interrupt preemption but MUST NOT have * interrupts disabled here. * XXX we may need to hold schedlock to get a coherent pm_active */ if (pmap->pm_active == -1 || pmap->pm_active == all_cpus) { invlpg(va); smp_invlpg(va); } else { cpumask = PCPU_GET(cpumask); other_cpus = PCPU_GET(other_cpus); if (pmap->pm_active & cpumask) invlpg(va); if (pmap->pm_active & other_cpus) smp_masked_invlpg(pmap->pm_active & other_cpus, va); } critical_exit(); } void pmap_invalidate_range(pmap_t pmap, vm_offset_t sva, vm_offset_t eva) { u_int cpumask; u_int other_cpus; vm_offset_t addr; critical_enter(); /* * We need to disable interrupt preemption but MUST NOT have * interrupts disabled here. * XXX we may need to hold schedlock to get a coherent pm_active */ if (pmap->pm_active == -1 || pmap->pm_active == all_cpus) { for (addr = sva; addr < eva; addr += PAGE_SIZE) invlpg(addr); smp_invlpg_range(sva, eva); } else { cpumask = PCPU_GET(cpumask); other_cpus = PCPU_GET(other_cpus); if (pmap->pm_active & cpumask) for (addr = sva; addr < eva; addr += PAGE_SIZE) invlpg(addr); if (pmap->pm_active & other_cpus) smp_masked_invlpg_range(pmap->pm_active & other_cpus, sva, eva); } critical_exit(); } void pmap_invalidate_all(pmap_t pmap) { u_int cpumask; u_int other_cpus; #ifdef SWTCH_OPTIM_STATS tlb_flush_count++; #endif critical_enter(); /* * We need to disable interrupt preemption but MUST NOT have * interrupts disabled here. * XXX we may need to hold schedlock to get a coherent pm_active */ if (pmap->pm_active == -1 || pmap->pm_active == all_cpus) { invltlb(); smp_invltlb(); } else { cpumask = PCPU_GET(cpumask); other_cpus = PCPU_GET(other_cpus); if (pmap->pm_active & cpumask) invltlb(); if (pmap->pm_active & other_cpus) smp_masked_invltlb(pmap->pm_active & other_cpus); } critical_exit(); } #else /* !SMP */ /* * Normal, non-SMP, 486+ invalidation functions. * We inline these within pmap.c for speed. */ PMAP_INLINE void pmap_invalidate_page(pmap_t pmap, vm_offset_t va) { if (pmap == kernel_pmap || 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 || 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 || pmap->pm_active) invltlb(); } #endif /* !SMP */ #endif /* !I386_CPU */ /* * Return an address which is the base of the Virtual mapping of * all the PTEs for the given pmap. Note this doesn't say that * all the PTEs will be present or that the pages there are valid. * The PTEs are made available by the recursive mapping trick. * It will map in the alternate PTE space if needed. */ static pt_entry_t * get_ptbase(pmap) pmap_t pmap; { pd_entry_t frame; /* are we current address space or kernel? */ if (pmap == kernel_pmap) return PTmap; frame = pmap->pm_pdir[PTDPTDI] & PG_FRAME; if (frame == (PTDpde & PG_FRAME)) return PTmap; /* otherwise, we are alternate address space */ if (frame != (APTDpde & PG_FRAME)) { APTDpde = (pd_entry_t) (frame | PG_RW | PG_V); pmap_invalidate_all(kernel_pmap); /* XXX Bandaid */ } return APTmap; } /* * Super fast pmap_pte routine best used when scanning * the pv lists. This eliminates many coarse-grained * invltlb calls. Note that many of the pv list * scans are across different pmaps. It is very wasteful * to do an entire invltlb for checking a single mapping. */ static pt_entry_t * pmap_pte_quick(pmap, va) register pmap_t pmap; vm_offset_t va; { pd_entry_t pde, newpf; pde = pmap->pm_pdir[va >> PDRSHIFT]; if (pde != 0) { pd_entry_t frame = pmap->pm_pdir[PTDPTDI] & PG_FRAME; unsigned index = i386_btop(va); /* are we current address space or kernel? */ if (pmap == kernel_pmap || frame == (PTDpde & PG_FRAME)) return PTmap + index; newpf = pde & PG_FRAME; if (((*PMAP1) & PG_FRAME) != newpf) { *PMAP1 = newpf | PG_RW | PG_V; pmap_invalidate_page(kernel_pmap, (vm_offset_t)PADDR1); } return PADDR1 + (index & (NPTEPG - 1)); } return (0); } /* * Routine: pmap_extract * Function: * Extract the physical page address associated * with the given map/virtual_address pair. */ vm_offset_t pmap_extract(pmap, va) register pmap_t pmap; vm_offset_t va; { vm_offset_t rtval; /* XXX FIXME */ vm_offset_t pdirindex; if (pmap == 0) return 0; pdirindex = va >> PDRSHIFT; rtval = pmap->pm_pdir[pdirindex]; if (rtval != 0) { pt_entry_t *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; } /*************************************************** * 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_offset_t pa) { pt_entry_t *pte; pte = vtopte(va); *pte = pa | PG_RW | PG_V | pgeflag; } /* * 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 = 0; } /* * 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_offset_t start, vm_offset_t end, int prot) { vm_offset_t va, sva; va = sva = *virt; while (start < end) { pmap_kenter(va, start); va += PAGE_SIZE; start += PAGE_SIZE; } pmap_invalidate_range(kernel_pmap, sva, va); *virt = va; return (sva); } /* * Add a list of wired pages to the kva * this routine is only used for temporary * kernel mappings that do not need to have * page modification or references recorded. * Note that old mappings are simply written * over. The page *must* be wired. * Note: SMP coherent. Uses a ranged shootdown IPI. */ void pmap_qenter(vm_offset_t sva, vm_page_t *m, int count) { vm_offset_t va; va = sva; while (count-- > 0) { pmap_kenter(va, VM_PAGE_TO_PHYS(*m)); va += PAGE_SIZE; m++; } pmap_invalidate_range(kernel_pmap, sva, va); } /* * 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); } 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 the kernel stack (including pcb for i386) for a new thread. * This routine directly affects the fork perf for a process and * create performance for a thread. */ void pmap_new_thread(struct thread *td) { int i; vm_page_t ma[KSTACK_PAGES]; vm_object_t ksobj; vm_page_t m; vm_offset_t ks; /* * allocate object for the kstack */ ksobj = vm_object_allocate(OBJT_DEFAULT, KSTACK_PAGES); td->td_kstack_obj = ksobj; /* get a kernel virtual address for the kstack for this thread */ #ifdef KSTACK_GUARD ks = kmem_alloc_nofault(kernel_map, (KSTACK_PAGES + 1) * PAGE_SIZE); if (ks == 0) panic("pmap_new_thread: kstack allocation failed"); if (*vtopte(ks) != 0) pmap_qremove(ks, 1); ks += PAGE_SIZE; td->td_kstack = ks; #else /* get a kernel virtual address for the kstack for this thread */ ks = kmem_alloc_nofault(kernel_map, KSTACK_PAGES * PAGE_SIZE); if (ks == 0) panic("pmap_new_thread: kstack allocation failed"); td->td_kstack = ks; #endif /* * For the length of the stack, link in a real page of ram for each * page of stack. */ for (i = 0; i < KSTACK_PAGES; i++) { /* * Get a kernel stack page */ m = vm_page_grab(ksobj, i, VM_ALLOC_NORMAL | VM_ALLOC_RETRY | VM_ALLOC_WIRED); ma[i] = m; vm_page_wakeup(m); vm_page_flag_clear(m, PG_ZERO); m->valid = VM_PAGE_BITS_ALL; } pmap_qenter(ks, ma, KSTACK_PAGES); } /* * Dispose the kernel stack for a thread that has exited. * This routine directly impacts the exit perf of a process and thread. */ void pmap_dispose_thread(td) struct thread *td; { int i; vm_object_t ksobj; vm_offset_t ks; vm_page_t m; ksobj = td->td_kstack_obj; ks = td->td_kstack; pmap_qremove(ks, KSTACK_PAGES); for (i = 0; i < KSTACK_PAGES; i++) { m = vm_page_lookup(ksobj, i); if (m == NULL) panic("pmap_dispose_thread: kstack already missing?"); vm_page_lock_queues(); vm_page_busy(m); vm_page_unwire(m, 0); vm_page_free(m); vm_page_unlock_queues(); } /* * Free the space that this stack was mapped to in the kernel * address map. */ #ifdef KSTACK_GUARD kmem_free(kernel_map, ks - PAGE_SIZE, (KSTACK_PAGES + 1) * PAGE_SIZE); #else kmem_free(kernel_map, ks, KSTACK_PAGES * PAGE_SIZE); #endif vm_object_deallocate(ksobj); } /* * Allow the Kernel stack for a thread to be prejudicially paged out. */ void pmap_swapout_thread(td) struct thread *td; { int i; vm_object_t ksobj; vm_offset_t ks; vm_page_t m; ksobj = td->td_kstack_obj; ks = td->td_kstack; pmap_qremove(ks, KSTACK_PAGES); for (i = 0; i < KSTACK_PAGES; i++) { m = vm_page_lookup(ksobj, i); if (m == NULL) panic("pmap_swapout_thread: kstack already missing?"); vm_page_lock_queues(); vm_page_dirty(m); vm_page_unwire(m, 0); vm_page_unlock_queues(); } } /* * Bring the kernel stack for a specified thread back in. */ void pmap_swapin_thread(td) struct thread *td; { int i, rv; vm_page_t ma[KSTACK_PAGES]; vm_object_t ksobj; vm_offset_t ks; vm_page_t m; ksobj = td->td_kstack_obj; ks = td->td_kstack; for (i = 0; i < KSTACK_PAGES; i++) { m = vm_page_grab(ksobj, i, VM_ALLOC_NORMAL | VM_ALLOC_RETRY); if (m->valid != VM_PAGE_BITS_ALL) { rv = vm_pager_get_pages(ksobj, &m, 1, 0); if (rv != VM_PAGER_OK) panic("pmap_swapin_thread: cannot get kstack for proc: %d\n", td->td_proc->p_pid); m = vm_page_lookup(ksobj, i); m->valid = VM_PAGE_BITS_ALL; } ma[i] = m; vm_page_lock_queues(); vm_page_wire(m); vm_page_wakeup(m); vm_page_unlock_queues(); } pmap_qenter(ks, ma, KSTACK_PAGES); } /*************************************************** * 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) { while (vm_page_sleep_busy(m, FALSE, "pmuwpt")) ; if (m->hold_count == 0) { vm_offset_t pteva; /* * unmap the page table page */ pmap->pm_pdir[m->pindex] = 0; --pmap->pm_stats.resident_count; if ((pmap->pm_pdir[PTDPTDI] & PG_FRAME) == (PTDpde & PG_FRAME)) { /* * Do a invltlb to make the invalidated mapping * take effect immediately. */ pteva = VM_MAXUSER_ADDRESS + i386_ptob(m->pindex); pmap_invalidate_page(pmap, pteva); } 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); --cnt.v_wire_count; } return 1; } return 0; } static PMAP_INLINE int pmap_unwire_pte_hold(pmap_t pmap, vm_page_t m) { vm_page_unhold(m); if (m->hold_count == 0) return _pmap_unwire_pte_hold(pmap, m); 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) { unsigned ptepindex; if (va >= VM_MAXUSER_ADDRESS) return 0; if (mpte == NULL) { ptepindex = (va >> PDRSHIFT); 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; } } return pmap_unwire_pte_hold(pmap, mpte); } void pmap_pinit0(pmap) 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); #ifndef I386_CPU invlpg((vm_offset_t)pmap->pm_pdir); #else invltlb(); #endif pmap->pm_ptphint = NULL; pmap->pm_active = 0; TAILQ_INIT(&pmap->pm_pvlist); bzero(&pmap->pm_stats, sizeof pmap->pm_stats); LIST_INSERT_HEAD(&allpmaps, pmap, pm_list); } /* * Initialize a preallocated and zeroed pmap structure, * such as one in a vmspace structure. */ void pmap_pinit(pmap) register 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 | VM_ALLOC_WIRED | VM_ALLOC_ZERO); vm_page_flag_clear(ptdpg, PG_MAPPED | PG_BUSY); /* not usually mapped*/ ptdpg->valid = VM_PAGE_BITS_ALL; pmap_qenter((vm_offset_t) pmap->pm_pdir, &ptdpg, 1); if ((ptdpg->flags & PG_ZERO) == 0) bzero(pmap->pm_pdir, PAGE_SIZE); LIST_INSERT_HEAD(&allpmaps, pmap, pm_list); /* Wire in kernel global address entries. */ /* XXX copies current process, does not fill in MPPTDI */ bcopy(PTD + KPTDI, pmap->pm_pdir + KPTDI, nkpt * PTESIZE); #ifdef SMP pmap->pm_pdir[MPPTDI] = PTD[MPPTDI]; #endif /* install self-referential address mapping entry */ pmap->pm_pdir[PTDPTDI] = VM_PAGE_TO_PHYS(ptdpg) | PG_V | PG_RW | PG_A | PG_M; 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(pmap) struct pmap *pmap; { /* XXX: Remove this stub when no longer called */ } static int pmap_release_free_page(pmap_t pmap, vm_page_t p) { pd_entry_t *pde = 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_lock_queues(); 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); #ifdef SMP pde[MPPTDI] = 0; #endif 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--; cnt.v_wire_count--; vm_page_free_zero(p); vm_page_unlock_queues(); return 1; } /* * this routine is called if the page table page is not * mapped correctly. */ static vm_page_t _pmap_allocpte(pmap, ptepindex) pmap_t pmap; unsigned ptepindex; { vm_offset_t pteva, ptepa; /* XXXPA */ vm_page_t m; /* * Find or fabricate a new pagetable page */ m = vm_page_grab(pmap->pm_pteobj, ptepindex, VM_ALLOC_WIRED | VM_ALLOC_ZERO | VM_ALLOC_RETRY); KASSERT(m->queue == PQ_NONE, ("_pmap_allocpte: %p->queue != PQ_NONE", m)); /* * 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 ((pmap->pm_pdir[PTDPTDI] & PG_FRAME) == (PTDpde & PG_FRAME)) { pteva = VM_MAXUSER_ADDRESS + i386_ptob(ptepindex); bzero((caddr_t) pteva, PAGE_SIZE); } else { pmap_zero_page(m); } } m->valid = VM_PAGE_BITS_ALL; vm_page_flag_clear(m, PG_ZERO); vm_page_wakeup(m); return m; } static vm_page_t pmap_allocpte(pmap_t pmap, vm_offset_t va) { unsigned ptepindex; pd_entry_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; pmap_invalidate_all(kernel_pmap); } /* * 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(pmap_t pmap) { vm_page_t p,n,ptdpg; vm_object_t object = pmap->pm_pteobj; int curgeneration; #if defined(DIAGNOSTIC) if (object->ref_count != 1) panic("pmap_release: pteobj reference count != 1"); #endif ptdpg = NULL; LIST_REMOVE(pmap, pm_list); retry: 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)) goto retry; } } 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 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_SYSTEM | VM_ALLOC_WIRED); if (!nkpg) panic("pmap_growkernel: no memory to grow kernel"); nkpt++; pmap_zero_page(nkpg); ptppaddr = VM_PAGE_TO_PHYS(nkpg); newpdir = (pd_entry_t) (ptppaddr | PG_V | PG_RW | PG_A | PG_M); pdir_pde(PTD, kernel_vm_end) = newpdir; LIST_FOREACH(pmap, &allpmaps, pm_list) { *pmap_pde(pmap, kernel_vm_end) = newpdir; } kernel_vm_end = (kernel_vm_end + PAGE_SIZE * NPTEPG) & ~(PAGE_SIZE * NPTEPG - 1); } splx(s); } /*************************************************** * page management routines. ***************************************************/ /* * free the pv_entry back to the free list */ static PMAP_INLINE void free_pv_entry(pv_entry_t pv) { pv_entry_count--; uma_zfree(pvzone, pv); } /* * get a new pv_entry, allocating a block from the system * when needed. * the memory allocation is performed bypassing the malloc code * because of the possibility of allocations at interrupt time. */ 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 uma_zalloc(pvzone, M_NOWAIT); } /* * This routine is very drastic, but can save the system * in a pinch. */ void pmap_collect() { 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 | PG_UNMANAGED))) 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(pmap_t pmap, vm_page_t m, vm_offset_t va) { 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); 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(pmap_t pmap, pt_entry_t *ptq, vm_offset_t va) { pt_entry_t oldpte; vm_page_t m; oldpte = atomic_readandclear_int(ptq); if (oldpte & PG_W) pmap->pm_stats.wired_count -= 1; /* * Machines that don't support invlpg, also don't support * PG_G. */ if (oldpte & PG_G) pmap_invalidate_page(kernel_pmap, va); pmap->pm_stats.resident_count -= 1; if (oldpte & PG_MANAGED) { m = PHYS_TO_VM_PAGE(oldpte); 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); } else { return pmap_unuse_pt(pmap, va, NULL); } return 0; } /* * Remove a single page from a process address space */ static void pmap_remove_page(pmap_t pmap, vm_offset_t va) { register pt_entry_t *ptq; /* * if there is no pte for this address, just skip it!!! */ if (*pmap_pde(pmap, va) == 0) { return; } /* * get a local va for mappings for this pmap. */ ptq = get_ptbase(pmap) + i386_btop(va); if (*ptq) { (void) pmap_remove_pte(pmap, ptq, va); pmap_invalidate_page(pmap, va); } return; } /* * 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) { register pt_entry_t *ptbase; vm_offset_t pdnxt; pd_entry_t ptpaddr; vm_offset_t sindex, eindex; int anyvalid; if (pmap == NULL) return; if (pmap->pm_stats.resident_count == 0) return; /* * special handling of removing one page. a very * common operation and easy to short circuit some * code. */ if ((sva + PAGE_SIZE == eva) && ((pmap->pm_pdir[(sva >> PDRSHIFT)] & PG_PS) == 0)) { pmap_remove_page(pmap, sva); return; } anyvalid = 0; /* * 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; ptpaddr = pmap->pm_pdir[pdirindex]; if ((ptpaddr & PG_PS) != 0) { pmap->pm_pdir[pdirindex] = 0; pmap->pm_stats.resident_count -= NBPDR / PAGE_SIZE; anyvalid++; 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); anyvalid++; if (pmap_remove_pte(pmap, ptbase + sindex, va)) break; } } if (anyvalid) pmap_invalidate_all(pmap); } /* * 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...) */ static void pmap_remove_all(vm_page_t m) { register pv_entry_t pv; pt_entry_t *pte, tpte; 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%x", VM_PAGE_TO_PHYS(m)); } #endif 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); tpte = atomic_readandclear_int(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); } pmap_invalidate_page(pv->pv_pmap, pv->pv_va); 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); free_pv_entry(pv); } vm_page_flag_clear(m, PG_MAPPED | PG_WRITEABLE); splx(s); } /* * 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) { register pt_entry_t *ptbase; vm_offset_t pdnxt; pd_entry_t ptpaddr; vm_offset_t sindex, eindex; int anychanged; if (pmap == NULL) return; if ((prot & VM_PROT_READ) == VM_PROT_NONE) { pmap_remove(pmap, sva, eva); return; } if (prot & VM_PROT_WRITE) return; anychanged = 0; 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; ptpaddr = pmap->pm_pdir[pdirindex]; if ((ptpaddr & PG_PS) != 0) { pmap->pm_pdir[pdirindex] &= ~(PG_M|PG_RW); pmap->pm_stats.resident_count -= NBPDR / PAGE_SIZE; anychanged++; 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++) { pt_entry_t pbits; vm_page_t m; 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; anychanged = 1; } } } if (anychanged) pmap_invalidate_all(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_page_t m, vm_prot_t prot, boolean_t wired) { vm_offset_t pa; register pt_entry_t *pte; vm_offset_t opa; pt_entry_t origpte, newpte; vm_page_t mpte; 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 < VM_MAXUSER_ADDRESS) { mpte = pmap_allocpte(pmap, va); } #if 0 && defined(PMAP_DIAGNOSTIC) else { pd_entry_t *pdeaddr = pmap_pde(pmap, va); origpte = *pdeaddr; if ((origpte & PG_V) == 0) { panic("pmap_enter: invalid kernel page table page, pdir=%p, pde=%p, va=%p\n", pmap->pm_pdir[PTDPTDI], origpte, va); } } #endif 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=%p, va=0x%x\n", (void *)pmap->pm_pdir[PTDPTDI], va); } pa = VM_PAGE_TO_PHYS(m) & PG_FRAME; 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_invalidate_page(pmap, va); } 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); 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 < VM_MAXUSER_ADDRESS) newpte |= PG_U; if (pmap == kernel_pmap) newpte |= pgeflag; /* * if the mapping or permission bits are different, we need * to update the pte. */ if ((origpte & ~(PG_M|PG_A)) != newpte) { *pte = newpte | PG_A; /*if (origpte)*/ { pmap_invalidate_page(pmap, va); } } } /* * 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) { pt_entry_t *pte; vm_offset_t pa; /* * In the case that a page table page is not * resident, we are creating it here. */ if (va < VM_MAXUSER_ADDRESS) { unsigned ptepindex; pd_entry_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 = 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 = vtopte(va); if (*pte) { if (mpte) pmap_unwire_pte_hold(pmap, mpte); 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_offset_t pa, int i) { vm_offset_t va; va = (vm_offset_t)crashdumpmap + (i * PAGE_SIZE); pmap_kenter(va, pa); #ifndef I386_CPU invlpg(va); #else invltlb(); #endif return ((void *)crashdumpmap); } #define MAX_INIT_PT (96) /* * pmap_object_init_pt 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_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; if (pmap == NULL || object == NULL) return; /* * 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; pd_entry_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_lock_queues(); vm_page_free(p); vm_page_unlock_queues(); return; } p = vm_page_lookup(object, pindex); vm_page_wakeup(p); } ptepa = 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] = ptepa | PG_U | PG_RW | PG_V | PG_PS; ptepa += NBPDR; ptepindex += 1; } vm_page_flag_set(p, PG_MAPPED); pmap_invalidate_all(kernel_pmap); return; } 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; } mpte = NULL; /* * if we are processing a major portion of the object, then scan the * entire thing. */ if (psize > (object->resident_page_count >> 2)) { objpgs = psize; for (p = TAILQ_FIRST(&object->memq); ((objpgs > 0) && (p != NULL)); p = TAILQ_NEXT(p, listq)) { if (p->pindex < pindex || p->pindex - pindex >= psize) { continue; } tmpidx = p->pindex - pindex; /* * don't allow an madvise to blow away our really * free pages allocating pv entries. */ if ((limit & MAP_PREFAULT_MADVISE) && cnt.v_free_count < cnt.v_free_reserved) { break; } vm_page_lock_queues(); 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); vm_page_unlock_queues(); mpte = pmap_enter_quick(pmap, addr + i386_ptob(tmpidx), p, mpte); vm_page_lock_queues(); vm_page_flag_set(p, PG_MAPPED); vm_page_wakeup(p); } vm_page_unlock_queues(); 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) && cnt.v_free_count < cnt.v_free_reserved) { break; } p = vm_page_lookup(object, tmpidx + pindex); if (p == NULL) continue; vm_page_lock_queues(); 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); vm_page_unlock_queues(); mpte = pmap_enter_quick(pmap, addr + i386_ptob(tmpidx), p, mpte); vm_page_lock_queues(); vm_page_flag_set(p, PG_MAPPED); vm_page_wakeup(p); } vm_page_unlock_queues(); } } return; } /* * 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, addra, entry) pmap_t pmap; vm_offset_t addra; vm_map_entry_t entry; { int i; vm_offset_t starta; vm_offset_t addr; vm_pindex_t pindex; vm_page_t m, mpte; vm_object_t object; if (!curthread || (pmap != vmspace_pmap(curthread->td_proc->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; } mpte = NULL; for (i = 0; i < PAGEORDER_SIZE; i++) { vm_object_t lobject; pt_entry_t *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 = 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; vm_page_lock_queues(); 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); vm_page_unlock_queues(); mpte = pmap_enter_quick(pmap, addr, m, mpte); vm_page_lock_queues(); vm_page_flag_set(m, PG_MAPPED); vm_page_wakeup(m); } vm_page_unlock_queues(); } } /* * 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, va, wired) register pmap_t pmap; vm_offset_t va; boolean_t wired; { register pt_entry_t *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. */ pmap_pte_set_w(pte, wired); } /* * 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_offset_t addr; vm_offset_t end_addr = src_addr + len; vm_offset_t pdnxt; pd_entry_t src_frame, dst_frame; vm_page_t m; if (dst_addr != src_addr) return; src_frame = src_pmap->pm_pdir[PTDPTDI] & PG_FRAME; if (src_frame != (PTDpde & PG_FRAME)) return; dst_frame = dst_pmap->pm_pdir[PTDPTDI] & PG_FRAME; for (addr = src_addr; addr < end_addr; addr = pdnxt) { pt_entry_t *src_pte, *dst_pte; vm_page_t dstmpte, srcmpte; pd_entry_t srcptepaddr; 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 (cnt.v_free_count < cnt.v_free_reserved || pv_entry_count > pv_entry_high_water) break; pdnxt = ((addr + PAGE_SIZE*NPTEPG) & ~(PAGE_SIZE*NPTEPG - 1)); ptepindex = addr >> PDRSHIFT; srcptepaddr = 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] = 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; /* * Have to recheck this before every avtopte() call below * in case we have blocked and something else used APTDpde. */ if (dst_frame != (APTDpde & PG_FRAME)) { APTDpde = dst_frame | PG_RW | PG_V; pmap_invalidate_all(kernel_pmap); /* XXX Bandaid */ } src_pte = vtopte(addr); dst_pte = avtopte(addr); while (addr < pdnxt) { pt_entry_t 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); } if (dstmpte->hold_count >= srcmpte->hold_count) break; } addr += PAGE_SIZE; src_pte++; dst_pte++; } } } #ifdef SMP /* * pmap_zpi_switchin*() * * These functions allow us to avoid doing IPIs alltogether in certain * temporary page-mapping situations (page zeroing). Instead to deal * with being preempted and moved onto a different cpu we invalidate * the page when the scheduler switches us in. This does not occur * very often so we remain relatively optimal with very little effort. */ static void pmap_zpi_switchin12(void) { invlpg((u_int)CADDR1); invlpg((u_int)CADDR2); } static void pmap_zpi_switchin2(void) { invlpg((u_int)CADDR2); } static void pmap_zpi_switchin3(void) { invlpg((u_int)CADDR3); } #endif /* * 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 phys; phys = VM_PAGE_TO_PHYS(m); if (*CMAP2) panic("pmap_zero_page: CMAP2 busy"); *CMAP2 = PG_V | PG_RW | phys | PG_A | PG_M; #ifdef I386_CPU invltlb(); #else #ifdef SMP curthread->td_switchin = pmap_zpi_switchin2; #endif invlpg((u_int)CADDR2); #endif #if defined(I686_CPU) if (cpu_class == CPUCLASS_686) i686_pagezero(CADDR2); else #endif bzero(CADDR2, PAGE_SIZE); #ifdef SMP curthread->td_switchin = NULL; #endif *CMAP2 = 0; } /* * 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 phys; phys = VM_PAGE_TO_PHYS(m); if (*CMAP2) panic("pmap_zero_page: CMAP2 busy"); *CMAP2 = PG_V | PG_RW | phys | PG_A | PG_M; #ifdef I386_CPU invltlb(); #else #ifdef SMP curthread->td_switchin = pmap_zpi_switchin2; #endif invlpg((u_int)CADDR2); #endif #if defined(I686_CPU) if (cpu_class == CPUCLASS_686 && off == 0 && size == PAGE_SIZE) i686_pagezero(CADDR2); else #endif bzero((char *)CADDR2 + off, size); #ifdef SMP curthread->td_switchin = NULL; #endif *CMAP2 = 0; } /* * 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 phys; phys = VM_PAGE_TO_PHYS(m); if (*CMAP3) panic("pmap_zero_page: CMAP3 busy"); *CMAP3 = PG_V | PG_RW | phys | PG_A | PG_M; #ifdef I386_CPU invltlb(); #else #ifdef SMP curthread->td_switchin = pmap_zpi_switchin3; #endif invlpg((u_int)CADDR3); #endif #if defined(I686_CPU) if (cpu_class == CPUCLASS_686) i686_pagezero(CADDR3); else #endif bzero(CADDR3, PAGE_SIZE); #ifdef SMP curthread->td_switchin = NULL; #endif *CMAP3 = 0; } /* * pmap_copy_page copies the specified (machine independent) * page by mapping the page into virtual memory and using * bcopy to copy the page, one machine dependent page at a * time. */ void pmap_copy_page(vm_page_t src, vm_page_t dst) { if (*CMAP1) panic("pmap_copy_page: CMAP1 busy"); if (*CMAP2) panic("pmap_copy_page: CMAP2 busy"); *CMAP1 = PG_V | VM_PAGE_TO_PHYS(src) | PG_A; *CMAP2 = PG_V | PG_RW | VM_PAGE_TO_PHYS(dst) | PG_A | PG_M; #ifdef I386_CPU invltlb(); #else #ifdef SMP curthread->td_switchin = pmap_zpi_switchin12; #endif invlpg((u_int)CADDR1); invlpg((u_int)CADDR2); #endif bcopy(CADDR1, CADDR2, PAGE_SIZE); #ifdef SMP curthread->td_switchin = NULL; #endif *CMAP1 = 0; *CMAP2 = 0; } /* * 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, sva, eva, pageable) pmap_t pmap; vm_offset_t sva, 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, m) 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, sva, eva) pmap_t pmap; vm_offset_t sva, eva; { pt_entry_t *pte, tpte; vm_page_t m; pv_entry_t pv, npv; int s; #ifdef PMAP_REMOVE_PAGES_CURPROC_ONLY if (!curthread || (pmap != vmspace_pmap(curthread->td_proc->p_vmspace))) { printf("warning: pmap_remove_pages called with non-current pmap\n"); return; } #endif 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 = vtopte(pv->pv_va); #else pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va); #endif tpte = *pte; if (tpte == 0) { printf("TPTE at %p IS ZERO @ VA %08x\n", pte, pv->pv_va); panic("bad pte"); } /* * We cannot remove wired pages from a process' mapping at this time */ if (tpte & PG_W) { npv = TAILQ_NEXT(pv, pv_plist); continue; } m = PHYS_TO_VM_PAGE(tpte); KASSERT(m->phys_addr == (tpte & PG_FRAME), ("vm_page_t %p phys_addr mismatch %08x %08x", m, m->phys_addr, tpte)); KASSERT(m < &vm_page_array[vm_page_array_size], ("pmap_remove_pages: bad tpte %x", tpte)); pv->pv_pmap->pm_stats.resident_count--; *pte = 0; /* * 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); free_pv_entry(pv); } splx(s); pmap_invalidate_all(pmap); } /* * 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(m, bit) vm_page_t m; int bit; { pv_entry_t pv; pt_entry_t *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) { register pv_entry_t pv; register pt_entry_t *pte; int s; if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) return; 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 pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va); if (setem) { *pte |= bit; pmap_invalidate_page(pv->pv_pmap, pv->pv_va); } else { pt_entry_t pbits = *pte; if (pbits & bit) { if (bit == PG_RW) { if (pbits & PG_M) { vm_page_dirty(m); } *pte = pbits & ~(PG_M|PG_RW); } else { *pte = pbits & ~bit; } pmap_invalidate_page(pv->pv_pmap, pv->pv_va); } } } 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_offset_t pmap_phys_address(ppn) 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) { register pv_entry_t pv, pvf, pvn; pt_entry_t *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)) { *pte &= ~PG_A; pmap_invalidate_page(pv->pv_pmap, pv->pv_va); 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() { register 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. */ void * pmap_mapdev(pa, size) vm_offset_t pa; vm_size_t size; { vm_offset_t va, tmpva, offset; offset = pa & PAGE_MASK; size = round_page(offset + size); pa = trunc_page(pa); /* We have a 1MB direct mapped region at KERNBASE */ if (pa < 0x00100000 && pa + size <= 0x00100000) return (void *)(pa + offset + KERNBASE); GIANT_REQUIRED; va = kmem_alloc_pageable(kernel_map, size); if (!va) panic("pmap_mapdev: Couldn't alloc kernel virtual memory"); for (tmpva = va; size > 0; ) { pmap_kenter(tmpva, pa); size -= PAGE_SIZE; tmpva += PAGE_SIZE; pa += PAGE_SIZE; } pmap_invalidate_range(kernel_pmap, va, tmpva); return (void *)(va + offset); } void pmap_unmapdev(va, size) vm_offset_t va; vm_size_t size; { vm_offset_t base, offset, tmpva; pt_entry_t *pte; base = va & PG_FRAME; offset = va & PAGE_MASK; size = round_page(offset + size); if (base >= KERNBASE && va + size <= KERNBASE + 0x00100000) return; /* direct mapped */ for (tmpva = base; tmpva < (base + size); tmpva += PAGE_SIZE) { pte = vtopte(tmpva); *pte = 0; } pmap_invalidate_range(kernel_pmap, va, tmpva); kmem_free(kernel_map, base, size); } /* * perform the pmap work for mincore */ int pmap_mincore(pmap, addr) pmap_t pmap; vm_offset_t addr; { pt_entry_t *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 thread *td) { struct proc *p = td->td_proc; pmap_t pmap; u_int32_t cr3; pmap = vmspace_pmap(td->td_proc->p_vmspace); #if defined(SMP) pmap->pm_active |= PCPU_GET(cpumask); #else pmap->pm_active |= 1; #endif cr3 = vtophys(pmap->pm_pdir); /* XXXKSE this is wrong. * pmap_activate is for the current thread on the current cpu */ if (p->p_flag & P_KSES) { /* Make sure all other cr3 entries are updated. */ /* what if they are running? XXXKSE (maybe abort them) */ FOREACH_THREAD_IN_PROC(p, td) { td->td_pcb->pcb_cr3 = cr3; } } else { td->td_pcb->pcb_cr3 = cr3; } load_cr3(cr3); #ifdef SWTCH_OPTIM_STATS tlb_flush_count++; #endif } 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) pmap_pid_dump(int pid) { pmap_t pmap; struct proc *p; int npte = 0; int index; sx_slock(&allproc_lock); LIST_FOREACH(p, &allproc, p_list) { 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 < NPDEPG; i++) { pd_entry_t *pde; pt_entry_t *pte; vm_offset_t base = i << PDRSHIFT; pde = &pmap->pm_pdir[i]; if (pde && pmap_pde_v(pde)) { for (j = 0; j < NPTEPG; j++) { vm_offset_t va = base + (j << PAGE_SHIFT); if (va >= (vm_offset_t) VM_MIN_KERNEL_ADDRESS) { if (index) { index = 0; printf("\n"); } sx_sunlock(&allproc_lock); return npte; } pte = pmap_pte_quick(pmap, va); if (pte && pmap_pte_v(pte)) { pt_entry_t pa; vm_page_t m; pa = *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(" "); } } } } } } } sx_sunlock(&allproc_lock); return npte; } #endif #if defined(DEBUG) static void pads(pmap_t pm); void pmap_pvdump(vm_offset_t pa); /* print address space of pmap*/ static void pads(pm) pmap_t pm; { int i, j; vm_offset_t va; pt_entry_t *ptep; if (pm == kernel_pmap) return; for (i = 0; i < NPDEPG; i++) if (pm->pm_pdir[i]) for (j = 0; j < NPTEPG; j++) { va = (i << PDRSHIFT) + (j << PAGE_SHIFT); if (pm == kernel_pmap && va < KERNBASE) continue; if (pm != kernel_pmap && va > UPT_MAX_ADDRESS) continue; ptep = pmap_pte_quick(pm, va); if (pmap_pte_v(ptep)) printf("%x:%x ", va, *ptep); }; } void pmap_pvdump(pa) vm_offset_t pa; { pv_entry_t pv; vm_page_t m; printf("pa %x", pa); m = PHYS_TO_VM_PAGE(pa); TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) { printf(" -> pmap %p, va %x", (void *)pv->pv_pmap, pv->pv_va); pads(pv->pv_pmap); } printf(" "); } #endif