/* $NetBSD: pmap.h,v 1.11 2001/07/28 18:12:44 chris Exp $ */ /* * Copyright (c) 1994,1995 Mark Brinicombe. * All rights reserved. * * 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 Mark Brinicombe * 4. The name of the author may not be used to endorse or promote products * derived from this software without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. * IN NO EVENT SHALL THE AUTHOR 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. */ #ifndef _ARM32_PMAP_H_ #define _ARM32_PMAP_H_ #include #include /* * a pmap describes a processes' 4GB virtual address space. this * virtual address space can be broken up into 4096 1MB regions which * are described by PDEs in the PDP. the PDEs are defined as follows: * * (ranges are inclusive -> exclusive, just like vm_map_entry start/end) * (the following assumes that KERNBASE is 0xf0000000) * * PDE#s VA range usage * 0->3835 0x0 -> 0xefc00000 user address space * 3836->3839 0xefc00000-> recursive mapping of PDP (used for * 0xf0000000 linear mapping of PTPs) * 3840->3851 0xf0000000-> kernel text address space (constant * 0xf0c00000 across all pmap's/processes) * 3852->3855 0xf0c00000-> "alternate" recursive PDP mapping * 0xf1000000 (for other pmaps) * 3856->4095 0xf1000000-> KVM and device mappings, constant * 0x00000000 across all pmaps * * The maths works out that to then map each 1MB block into 4k pages requires * 256 entries, of 4 bytes each, totaling 1k per 1MB. However as we use 4k * pages we allocate 4 PDE's at a time, allocating the same access permissions * to them all. This means we only need 1024 entries in the page table page * table, IE we use 1 4k page to linearly map all the other page tables used. */ /* * Data structures used by pmap */ /* * Structure that describes a Level 1 page table and the flags * associated with it. */ struct l1pt { SIMPLEQ_ENTRY(l1pt) pt_queue; /* Queue pointers */ struct pglist pt_plist; /* Allocated page list */ vaddr_t pt_va; /* Allocated virtual address */ int pt_flags; /* Flags */ }; #define PTFLAG_STATIC 1 /* Statically allocated */ #define PTFLAG_KPT 2 /* Kernel pt's are mapped */ #define PTFLAG_CLEAN 4 /* L1 is clean */ /* * The pmap structure itself. */ struct pmap { pd_entry_t *pm_pdir; /* KVA of page directory */ struct l1pt *pm_l1pt; /* L1 descriptor */ paddr_t pm_pptpt; /* PA of pt's page table */ vaddr_t pm_vptpt; /* VA of pt's page table */ short pm_count; /* pmap reference count */ struct simplelock pm_lock; /* lock on pmap */ struct pmap_statistics pm_stats; /* pmap statistics */ }; typedef struct pmap *pmap_t; /* * For each struct vm_page, there is a list of all currently valid virtual * mappings of that page. An entry is a pv_entry_t, the list is pv_table. */ typedef struct pv_entry { struct pv_entry *pv_next; /* next pv_entry */ struct pmap *pv_pmap; /* pmap where mapping lies */ vaddr_t pv_va; /* virtual address for mapping */ int pv_flags; /* flags */ } *pv_entry_t; /* * A pv_page_info struture looks like this. It is used to contain status * information for pv_entry freelists. */ struct pv_page; struct pv_page_info { TAILQ_ENTRY(pv_page) pgi_list; struct pv_entry *pgi_freelist; int pgi_nfree; }; /* * A pv_page itself looks like this. pv_entries are requested from the VM a * pv_page at a time. * * We also define a macro that states the number of pv_entries per page * allocated. */ #define NPVPPG ((NBPG - sizeof(struct pv_page_info)) / sizeof(struct pv_entry)) struct pv_page { struct pv_page_info pvp_pgi; struct pv_entry pvp_pv[NPVPPG]; }; /* * Page hooks. I'll eliminate these sometime soon :-) * * For speed we store the both the virtual address and the page table * entry address for each page hook. */ typedef struct { vaddr_t va; pt_entry_t *pte; } pagehook_t; /* * Physical / virtual address structure. In a number of places (particularly * during bootstrapping) we need to keep track of the physical and virtual * addresses of various pages */ typedef struct { paddr_t pv_pa; vaddr_t pv_va; } pv_addr_t; /* * _KERNEL specific macros, functions and prototypes */ #ifdef _KERNEL /* * Commonly referenced structures */ extern pv_entry_t pv_table; /* Phys to virt mappings, per page. */ extern struct pmap kernel_pmap_store; extern int pmap_debug_level; /* Only exists if PMAP_DEBUG */ /* * Macros that we need to export */ #define pmap_kernel() (&kernel_pmap_store) #define pmap_update() /* nothing (yet) */ #define pmap_resident_count(pmap) ((pmap)->pm_stats.resident_count) #define pmap_wired_count(pmap) ((pmap)->pm_stats.wired_count) #define pmap_phys_address(ppn) (arm_page_to_byte((ppn))) /* * Functions that we need to export */ extern boolean_t pmap_testbit __P((paddr_t, int)); extern void pmap_changebit __P((paddr_t, int, int)); extern vaddr_t pmap_map __P((vaddr_t, vaddr_t, vaddr_t, int)); extern void pmap_procwr __P((struct proc *, vaddr_t, int)); #define PMAP_NEED_PROCWR /* * Functions we use internally */ extern void pmap_bootstrap __P((pd_entry_t *, pv_addr_t)); extern void pmap_debug __P((int)); extern int pmap_handled_emulation __P((struct pmap *, vaddr_t)); extern int pmap_modified_emulation __P((struct pmap *, vaddr_t)); extern void pmap_postinit __P((void)); extern pt_entry_t *pmap_pte __P((struct pmap *, vaddr_t)); #endif /* _KERNEL */ /* * Useful macros and constants */ /* Virtual address to page table entry */ #define vtopte(va) \ ((pt_entry_t *)(PROCESS_PAGE_TBLS_BASE + \ (arm_byte_to_page((unsigned int)(va)) << 2))) /* Virtual address to physical address */ #define vtophys(va) \ ((*vtopte(va) & PG_FRAME) | ((unsigned int)(va) & ~PG_FRAME)) /* L1 and L2 page table macros */ #define pmap_pde(m, v) (&((m)->pm_pdir[((vaddr_t)(v) >> PDSHIFT)&4095])) #define pmap_pte_pa(pte) (*(pte) & PG_FRAME) #define pmap_pde_v(pde) (*(pde) != 0) #define pmap_pte_v(pte) (*(pte) != 0) /* Size of the kernel part of the L1 page table */ #define KERNEL_PD_SIZE \ (PD_SIZE - (KERNEL_SPACE_START >> PDSHIFT) * sizeof(pd_entry_t)) #endif /* _ARM32_PMAP_H_ */