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/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _PARISC_PGTABLE_H
#define _PARISC_PGTABLE_H
#include <asm/page.h>
#include <asm-generic/4level-fixup.h>
#include <asm/fixmap.h>
#ifndef __ASSEMBLY__
/*
* we simulate an x86-style page table for the linux mm code
*/
#include <linux/bitops.h>
#include <linux/spinlock.h>
#include <linux/mm_types.h>
#include <asm/processor.h>
#include <asm/cache.h>
static inline spinlock_t *pgd_spinlock(pgd_t *);
/*
* kern_addr_valid(ADDR) tests if ADDR is pointing to valid kernel
* memory. For the return value to be meaningful, ADDR must be >=
* PAGE_OFFSET. This operation can be relatively expensive (e.g.,
* require a hash-, or multi-level tree-lookup or something of that
* sort) but it guarantees to return TRUE only if accessing the page
* at that address does not cause an error. Note that there may be
* addresses for which kern_addr_valid() returns FALSE even though an
* access would not cause an error (e.g., this is typically true for
* memory mapped I/O regions.
*
* XXX Need to implement this for parisc.
*/
#define kern_addr_valid(addr) (1)
/* This is for the serialization of PxTLB broadcasts. At least on the N class
* systems, only one PxTLB inter processor broadcast can be active at any one
* time on the Merced bus.
* PTE updates are protected by locks in the PMD.
*/
extern spinlock_t pa_tlb_flush_lock;
extern spinlock_t pa_swapper_pg_lock;
#if defined(CONFIG_64BIT) && defined(CONFIG_SMP)
extern int pa_serialize_tlb_flushes;
#else
#define pa_serialize_tlb_flushes (0)
#endif
#define purge_tlb_start(flags) do { \
if (pa_serialize_tlb_flushes) \
spin_lock_irqsave(&pa_tlb_flush_lock, flags); \
else \
local_irq_save(flags); \
} while (0)
#define purge_tlb_end(flags) do { \
if (pa_serialize_tlb_flushes) \
spin_unlock_irqrestore(&pa_tlb_flush_lock, flags); \
else \
local_irq_restore(flags); \
} while (0)
/* Purge data and instruction TLB entries. The TLB purge instructions
* are slow on SMP machines since the purge must be broadcast to all CPUs.
*/
static inline void purge_tlb_entries(struct mm_struct *mm, unsigned long addr)
{
unsigned long flags;
purge_tlb_start(flags);
mtsp(mm->context, 1);
pdtlb(addr);
pitlb(addr);
purge_tlb_end(flags);
}
/* Certain architectures need to do special things when PTEs
* within a page table are directly modified. Thus, the following
* hook is made available.
*/
#define set_pte(pteptr, pteval) \
do{ \
*(pteptr) = (pteval); \
} while(0)
#define set_pte_at(mm, addr, ptep, pteval) \
do { \
pte_t old_pte; \
unsigned long flags; \
spin_lock_irqsave(pgd_spinlock((mm)->pgd), flags);\
old_pte = *ptep; \
set_pte(ptep, pteval); \
purge_tlb_entries(mm, addr); \
spin_unlock_irqrestore(pgd_spinlock((mm)->pgd), flags);\
} while (0)
#endif /* !__ASSEMBLY__ */
#define pte_ERROR(e) \
printk("%s:%d: bad pte %08lx.\n", __FILE__, __LINE__, pte_val(e))
#define pmd_ERROR(e) \
printk("%s:%d: bad pmd %08lx.\n", __FILE__, __LINE__, (unsigned long)pmd_val(e))
#define pgd_ERROR(e) \
printk("%s:%d: bad pgd %08lx.\n", __FILE__, __LINE__, (unsigned long)pgd_val(e))
/* This is the size of the initially mapped kernel memory */
#if defined(CONFIG_64BIT)
#define KERNEL_INITIAL_ORDER 26 /* 1<<26 = 64MB */
#else
#define KERNEL_INITIAL_ORDER 25 /* 1<<25 = 32MB */
#endif
#define KERNEL_INITIAL_SIZE (1 << KERNEL_INITIAL_ORDER)
#if CONFIG_PGTABLE_LEVELS == 3
#define PGD_ORDER 1 /* Number of pages per pgd */
#define PMD_ORDER 1 /* Number of pages per pmd */
#define PGD_ALLOC_ORDER (2 + 1) /* first pgd contains pmd */
#else
#define PGD_ORDER 1 /* Number of pages per pgd */
#define PGD_ALLOC_ORDER (PGD_ORDER + 1)
#endif
/* Definitions for 3rd level (we use PLD here for Page Lower directory
* because PTE_SHIFT is used lower down to mean shift that has to be
* done to get usable bits out of the PTE) */
#define PLD_SHIFT PAGE_SHIFT
#define PLD_SIZE PAGE_SIZE
#define BITS_PER_PTE (PAGE_SHIFT - BITS_PER_PTE_ENTRY)
#define PTRS_PER_PTE (1UL << BITS_PER_PTE)
/* Definitions for 2nd level */
#define PMD_SHIFT (PLD_SHIFT + BITS_PER_PTE)
#define PMD_SIZE (1UL << PMD_SHIFT)
#define PMD_MASK (~(PMD_SIZE-1))
#if CONFIG_PGTABLE_LEVELS == 3
#define BITS_PER_PMD (PAGE_SHIFT + PMD_ORDER - BITS_PER_PMD_ENTRY)
#else
#define __PAGETABLE_PMD_FOLDED 1
#define BITS_PER_PMD 0
#endif
#define PTRS_PER_PMD (1UL << BITS_PER_PMD)
/* Definitions for 1st level */
#define PGDIR_SHIFT (PMD_SHIFT + BITS_PER_PMD)
#if (PGDIR_SHIFT + PAGE_SHIFT + PGD_ORDER - BITS_PER_PGD_ENTRY) > BITS_PER_LONG
#define BITS_PER_PGD (BITS_PER_LONG - PGDIR_SHIFT)
#else
#define BITS_PER_PGD (PAGE_SHIFT + PGD_ORDER - BITS_PER_PGD_ENTRY)
#endif
#define PGDIR_SIZE (1UL << PGDIR_SHIFT)
#define PGDIR_MASK (~(PGDIR_SIZE-1))
#define PTRS_PER_PGD (1UL << BITS_PER_PGD)
#define USER_PTRS_PER_PGD PTRS_PER_PGD
#ifdef CONFIG_64BIT
#define MAX_ADDRBITS (PGDIR_SHIFT + BITS_PER_PGD)
#define MAX_ADDRESS (1UL << MAX_ADDRBITS)
#define SPACEID_SHIFT (MAX_ADDRBITS - 32)
#else
#define MAX_ADDRBITS (BITS_PER_LONG)
#define MAX_ADDRESS (1UL << MAX_ADDRBITS)
#define SPACEID_SHIFT 0
#endif
/* This calculates the number of initial pages we need for the initial
* page tables */
#if (KERNEL_INITIAL_ORDER) >= (PMD_SHIFT)
# define PT_INITIAL (1 << (KERNEL_INITIAL_ORDER - PMD_SHIFT))
#else
# define PT_INITIAL (1) /* all initial PTEs fit into one page */
#endif
/*
* pgd entries used up by user/kernel:
*/
#define FIRST_USER_ADDRESS 0UL
/* NB: The tlb miss handlers make certain assumptions about the order */
/* of the following bits, so be careful (One example, bits 25-31 */
/* are moved together in one instruction). */
#define _PAGE_READ_BIT 31 /* (0x001) read access allowed */
#define _PAGE_WRITE_BIT 30 /* (0x002) write access allowed */
#define _PAGE_EXEC_BIT 29 /* (0x004) execute access allowed */
#define _PAGE_GATEWAY_BIT 28 /* (0x008) privilege promotion allowed */
#define _PAGE_DMB_BIT 27 /* (0x010) Data Memory Break enable (B bit) */
#define _PAGE_DIRTY_BIT 26 /* (0x020) Page Dirty (D bit) */
#define _PAGE_REFTRAP_BIT 25 /* (0x040) Page Ref. Trap enable (T bit) */
#define _PAGE_NO_CACHE_BIT 24 /* (0x080) Uncached Page (U bit) */
#define _PAGE_ACCESSED_BIT 23 /* (0x100) Software: Page Accessed */
#define _PAGE_PRESENT_BIT 22 /* (0x200) Software: translation valid */
#define _PAGE_HPAGE_BIT 21 /* (0x400) Software: Huge Page */
#define _PAGE_USER_BIT 20 /* (0x800) Software: User accessible page */
/* N.B. The bits are defined in terms of a 32 bit word above, so the */
/* following macro is ok for both 32 and 64 bit. */
#define xlate_pabit(x) (31 - x)
/* this defines the shift to the usable bits in the PTE it is set so
* that the valid bits _PAGE_PRESENT_BIT and _PAGE_USER_BIT are set
* to zero */
#define PTE_SHIFT xlate_pabit(_PAGE_USER_BIT)
/* PFN_PTE_SHIFT defines the shift of a PTE value to access the PFN field */
#define PFN_PTE_SHIFT 12
#define _PAGE_READ (1 << xlate_pabit(_PAGE_READ_BIT))
#define _PAGE_WRITE (1 << xlate_pabit(_PAGE_WRITE_BIT))
#define _PAGE_RW (_PAGE_READ | _PAGE_WRITE)
#define _PAGE_EXEC (1 << xlate_pabit(_PAGE_EXEC_BIT))
#define _PAGE_GATEWAY (1 << xlate_pabit(_PAGE_GATEWAY_BIT))
#define _PAGE_DMB (1 << xlate_pabit(_PAGE_DMB_BIT))
#define _PAGE_DIRTY (1 << xlate_pabit(_PAGE_DIRTY_BIT))
#define _PAGE_REFTRAP (1 << xlate_pabit(_PAGE_REFTRAP_BIT))
#define _PAGE_NO_CACHE (1 << xlate_pabit(_PAGE_NO_CACHE_BIT))
#define _PAGE_ACCESSED (1 << xlate_pabit(_PAGE_ACCESSED_BIT))
#define _PAGE_PRESENT (1 << xlate_pabit(_PAGE_PRESENT_BIT))
#define _PAGE_HUGE (1 << xlate_pabit(_PAGE_HPAGE_BIT))
#define _PAGE_USER (1 << xlate_pabit(_PAGE_USER_BIT))
#define _PAGE_TABLE (_PAGE_PRESENT | _PAGE_READ | _PAGE_WRITE | _PAGE_DIRTY | _PAGE_ACCESSED)
#define _PAGE_CHG_MASK (PAGE_MASK | _PAGE_ACCESSED | _PAGE_DIRTY)
#define _PAGE_KERNEL_RO (_PAGE_PRESENT | _PAGE_READ | _PAGE_DIRTY | _PAGE_ACCESSED)
#define _PAGE_KERNEL_EXEC (_PAGE_KERNEL_RO | _PAGE_EXEC)
#define _PAGE_KERNEL_RWX (_PAGE_KERNEL_EXEC | _PAGE_WRITE)
#define _PAGE_KERNEL (_PAGE_KERNEL_RO | _PAGE_WRITE)
/* The pgd/pmd contains a ptr (in phys addr space); since all pgds/pmds
* are page-aligned, we don't care about the PAGE_OFFSET bits, except
* for a few meta-information bits, so we shift the address to be
* able to effectively address 40/42/44-bits of physical address space
* depending on 4k/16k/64k PAGE_SIZE */
#define _PxD_PRESENT_BIT 31
#define _PxD_ATTACHED_BIT 30
#define _PxD_VALID_BIT 29
#define PxD_FLAG_PRESENT (1 << xlate_pabit(_PxD_PRESENT_BIT))
#define PxD_FLAG_ATTACHED (1 << xlate_pabit(_PxD_ATTACHED_BIT))
#define PxD_FLAG_VALID (1 << xlate_pabit(_PxD_VALID_BIT))
#define PxD_FLAG_MASK (0xf)
#define PxD_FLAG_SHIFT (4)
#define PxD_VALUE_SHIFT (PFN_PTE_SHIFT-PxD_FLAG_SHIFT)
#ifndef __ASSEMBLY__
#define PAGE_NONE __pgprot(_PAGE_PRESENT | _PAGE_USER)
#define PAGE_SHARED __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_READ | _PAGE_WRITE)
/* Others seem to make this executable, I don't know if that's correct
or not. The stack is mapped this way though so this is necessary
in the short term - dhd@linuxcare.com, 2000-08-08 */
#define PAGE_READONLY __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_READ)
#define PAGE_WRITEONLY __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_WRITE)
#define PAGE_EXECREAD __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_READ | _PAGE_EXEC)
#define PAGE_COPY PAGE_EXECREAD
#define PAGE_RWX __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_READ | _PAGE_WRITE | _PAGE_EXEC)
#define PAGE_KERNEL __pgprot(_PAGE_KERNEL)
#define PAGE_KERNEL_EXEC __pgprot(_PAGE_KERNEL_EXEC)
#define PAGE_KERNEL_RWX __pgprot(_PAGE_KERNEL_RWX)
#define PAGE_KERNEL_RO __pgprot(_PAGE_KERNEL_RO)
#define PAGE_KERNEL_UNC __pgprot(_PAGE_KERNEL | _PAGE_NO_CACHE)
#define PAGE_GATEWAY __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_GATEWAY| _PAGE_READ)
/*
* We could have an execute only page using "gateway - promote to priv
* level 3", but that is kind of silly. So, the way things are defined
* now, we must always have read permission for pages with execute
* permission. For the fun of it we'll go ahead and support write only
* pages.
*/
/*xwr*/
#define __P000 PAGE_NONE
#define __P001 PAGE_READONLY
#define __P010 __P000 /* copy on write */
#define __P011 __P001 /* copy on write */
#define __P100 PAGE_EXECREAD
#define __P101 PAGE_EXECREAD
#define __P110 __P100 /* copy on write */
#define __P111 __P101 /* copy on write */
#define __S000 PAGE_NONE
#define __S001 PAGE_READONLY
#define __S010 PAGE_WRITEONLY
#define __S011 PAGE_SHARED
#define __S100 PAGE_EXECREAD
#define __S101 PAGE_EXECREAD
#define __S110 PAGE_RWX
#define __S111 PAGE_RWX
extern pgd_t swapper_pg_dir[]; /* declared in init_task.c */
/* initial page tables for 0-8MB for kernel */
extern pte_t pg0[];
/* zero page used for uninitialized stuff */
extern unsigned long *empty_zero_page;
/*
* ZERO_PAGE is a global shared page that is always zero: used
* for zero-mapped memory areas etc..
*/
#define ZERO_PAGE(vaddr) (virt_to_page(empty_zero_page))
#define pte_none(x) (pte_val(x) == 0)
#define pte_present(x) (pte_val(x) & _PAGE_PRESENT)
#define pte_clear(mm, addr, xp) set_pte_at(mm, addr, xp, __pte(0))
#define pmd_flag(x) (pmd_val(x) & PxD_FLAG_MASK)
#define pmd_address(x) ((unsigned long)(pmd_val(x) &~ PxD_FLAG_MASK) << PxD_VALUE_SHIFT)
#define pgd_flag(x) (pgd_val(x) & PxD_FLAG_MASK)
#define pgd_address(x) ((unsigned long)(pgd_val(x) &~ PxD_FLAG_MASK) << PxD_VALUE_SHIFT)
#if CONFIG_PGTABLE_LEVELS == 3
/* The first entry of the permanent pmd is not there if it contains
* the gateway marker */
#define pmd_none(x) (!pmd_val(x) || pmd_flag(x) == PxD_FLAG_ATTACHED)
#else
#define pmd_none(x) (!pmd_val(x))
#endif
#define pmd_bad(x) (!(pmd_flag(x) & PxD_FLAG_VALID))
#define pmd_present(x) (pmd_flag(x) & PxD_FLAG_PRESENT)
static inline void pmd_clear(pmd_t *pmd) {
#if CONFIG_PGTABLE_LEVELS == 3
if (pmd_flag(*pmd) & PxD_FLAG_ATTACHED)
/* This is the entry pointing to the permanent pmd
* attached to the pgd; cannot clear it */
__pmd_val_set(*pmd, PxD_FLAG_ATTACHED);
else
#endif
__pmd_val_set(*pmd, 0);
}
#if CONFIG_PGTABLE_LEVELS == 3
#define pgd_page_vaddr(pgd) ((unsigned long) __va(pgd_address(pgd)))
#define pgd_page(pgd) virt_to_page((void *)pgd_page_vaddr(pgd))
/* For 64 bit we have three level tables */
#define pgd_none(x) (!pgd_val(x))
#define pgd_bad(x) (!(pgd_flag(x) & PxD_FLAG_VALID))
#define pgd_present(x) (pgd_flag(x) & PxD_FLAG_PRESENT)
static inline void pgd_clear(pgd_t *pgd) {
#if CONFIG_PGTABLE_LEVELS == 3
if(pgd_flag(*pgd) & PxD_FLAG_ATTACHED)
/* This is the permanent pmd attached to the pgd; cannot
* free it */
return;
#endif
__pgd_val_set(*pgd, 0);
}
#else
/*
* The "pgd_xxx()" functions here are trivial for a folded two-level
* setup: the pgd is never bad, and a pmd always exists (as it's folded
* into the pgd entry)
*/
static inline int pgd_none(pgd_t pgd) { return 0; }
static inline int pgd_bad(pgd_t pgd) { return 0; }
static inline int pgd_present(pgd_t pgd) { return 1; }
static inline void pgd_clear(pgd_t * pgdp) { }
#endif
/*
* The following only work if pte_present() is true.
* Undefined behaviour if not..
*/
static inline int pte_dirty(pte_t pte) { return pte_val(pte) & _PAGE_DIRTY; }
static inline int pte_young(pte_t pte) { return pte_val(pte) & _PAGE_ACCESSED; }
static inline int pte_write(pte_t pte) { return pte_val(pte) & _PAGE_WRITE; }
static inline int pte_special(pte_t pte) { return 0; }
static inline pte_t pte_mkclean(pte_t pte) { pte_val(pte) &= ~_PAGE_DIRTY; return pte; }
static inline pte_t pte_mkold(pte_t pte) { pte_val(pte) &= ~_PAGE_ACCESSED; return pte; }
static inline pte_t pte_wrprotect(pte_t pte) { pte_val(pte) &= ~_PAGE_WRITE; return pte; }
static inline pte_t pte_mkdirty(pte_t pte) { pte_val(pte) |= _PAGE_DIRTY; return pte; }
static inline pte_t pte_mkyoung(pte_t pte) { pte_val(pte) |= _PAGE_ACCESSED; return pte; }
static inline pte_t pte_mkwrite(pte_t pte) { pte_val(pte) |= _PAGE_WRITE; return pte; }
static inline pte_t pte_mkspecial(pte_t pte) { return pte; }
/*
* Huge pte definitions.
*/
#ifdef CONFIG_HUGETLB_PAGE
#define pte_huge(pte) (pte_val(pte) & _PAGE_HUGE)
|