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/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _ASM_POWERPC_NOHASH_PGTABLE_H
#define _ASM_POWERPC_NOHASH_PGTABLE_H
#if defined(CONFIG_PPC64)
#include <asm/nohash/64/pgtable.h>
#else
#include <asm/nohash/32/pgtable.h>
#endif
/* Permission masks used for kernel mappings */
#define PAGE_KERNEL __pgprot(_PAGE_BASE | _PAGE_KERNEL_RW)
#define PAGE_KERNEL_NC __pgprot(_PAGE_BASE_NC | _PAGE_KERNEL_RW | _PAGE_NO_CACHE)
#define PAGE_KERNEL_NCG __pgprot(_PAGE_BASE_NC | _PAGE_KERNEL_RW | \
_PAGE_NO_CACHE | _PAGE_GUARDED)
#define PAGE_KERNEL_X __pgprot(_PAGE_BASE | _PAGE_KERNEL_RWX)
#define PAGE_KERNEL_RO __pgprot(_PAGE_BASE | _PAGE_KERNEL_RO)
#define PAGE_KERNEL_ROX __pgprot(_PAGE_BASE | _PAGE_KERNEL_ROX)
/*
* Protection used for kernel text. We want the debuggers to be able to
* set breakpoints anywhere, so don't write protect the kernel text
* on platforms where such control is possible.
*/
#if defined(CONFIG_KGDB) || defined(CONFIG_XMON) || defined(CONFIG_BDI_SWITCH) ||\
defined(CONFIG_KPROBES) || defined(CONFIG_DYNAMIC_FTRACE)
#define PAGE_KERNEL_TEXT PAGE_KERNEL_X
#else
#define PAGE_KERNEL_TEXT PAGE_KERNEL_ROX
#endif
/* Make modules code happy. We don't set RO yet */
#define PAGE_KERNEL_EXEC PAGE_KERNEL_X
/* Advertise special mapping type for AGP */
#define PAGE_AGP (PAGE_KERNEL_NC)
#define HAVE_PAGE_AGP
#ifndef __ASSEMBLY__
/* Generic accessors to PTE bits */
#ifndef pte_write
static inline int pte_write(pte_t pte)
{
return pte_val(pte) & _PAGE_RW;
}
#endif
static inline int pte_read(pte_t pte) { return 1; }
static inline int pte_dirty(pte_t pte) { return pte_val(pte) & _PAGE_DIRTY; }
static inline int pte_special(pte_t pte) { return pte_val(pte) & _PAGE_SPECIAL; }
static inline int pte_none(pte_t pte) { return (pte_val(pte) & ~_PTE_NONE_MASK) == 0; }
static inline bool pte_hashpte(pte_t pte) { return false; }
static inline bool pte_ci(pte_t pte) { return pte_val(pte) & _PAGE_NO_CACHE; }
static inline bool pte_exec(pte_t pte) { return pte_val(pte) & _PAGE_EXEC; }
#ifdef CONFIG_NUMA_BALANCING
/*
* These work without NUMA balancing but the kernel does not care. See the
* comment in include/linux/pgtable.h . On powerpc, this will only
* work for user pages and always return true for kernel pages.
*/
static inline int pte_protnone(pte_t pte)
{
return pte_present(pte) && !pte_user(pte);
}
static inline int pmd_protnone(pmd_t pmd)
{
return pte_protnone(pmd_pte(pmd));
}
#endif /* CONFIG_NUMA_BALANCING */
static inline int pte_present(pte_t pte)
{
return pte_val(pte) & _PAGE_PRESENT;
}
static inline bool pte_hw_valid(pte_t pte)
{
return pte_val(pte) & _PAGE_PRESENT;
}
/*
* Don't just check for any non zero bits in __PAGE_USER, since for book3e
* and PTE_64BIT, PAGE_KERNEL_X contains _PAGE_BAP_SR which is also in
* _PAGE_USER. Need to explicitly match _PAGE_BAP_UR bit in that case too.
*/
#ifndef pte_user
static inline bool pte_user(pte_t pte)
{
return (pte_val(pte) & _PAGE_USER) == _PAGE_USER;
}
#endif
/*
* We only find page table entry in the last level
* Hence no need for other accessors
*/
#define pte_access_permitted pte_access_permitted
static inline bool pte_access_permitted(pte_t pte, bool write)
{
/*
* A read-only access is controlled by _PAGE_USER bit.
* We have _PAGE_READ set for WRITE and EXECUTE
*/
if (!pte_present(pte) || !pte_user(pte) || !pte_read(pte))
return false;
if (write && !pte_write(pte))
return false;
return true;
}
/* Conversion functions: convert a page and protection to a page entry,
* and a page entry and page directory to the page they refer to.
*
* Even if PTEs can be unsigned long long, a PFN is always an unsigned
* long for now.
*/
static inline pte_t pfn_pte(unsigned long pfn, pgprot_t pgprot) {
return __pte(((pte_basic_t)(pfn) << PTE_RPN_SHIFT) |
pgprot_val(pgprot)); }
static inline unsigned long pte_pfn(pte_t pte) {
return pte_val(pte) >> PTE_RPN_SHIFT; }
/* Generic modifiers for PTE bits */
static inline pte_t pte_exprotect(pte_t pte)
{
return __pte(pte_val(pte) & ~_PAGE_EXEC);
}
static inline pte_t pte_mkclean(pte_t pte)
{
return __pte(pte_val(pte) & ~_PAGE_DIRTY);
}
static inline pte_t pte_mkold(pte_t pte)
{
return __pte(pte_val(pte) & ~_PAGE_ACCESSED);
}
static inline pte_t pte_mkspecial(pte_t pte)
{
return __pte(pte_val(pte) | _PAGE_SPECIAL);
}
#ifndef pte_mkhuge
static inline pte_t pte_mkhuge(pte_t pte)
{
return __pte(pte_val(pte));
}
#endif
#ifndef pte_mkprivileged
static inline pte_t pte_mkprivileged(pte_t pte)
{
return __pte(pte_val(pte) & ~_PAGE_USER);
}
#endif
#ifndef pte_mkuser
static inline pte_t pte_mkuser(pte_t pte)
{
return __pte(pte_val(pte) | _PAGE_USER);
}
#endif
static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
{
return __pte((pte_val(pte) & _PAGE_CHG_MASK) | pgprot_val(newprot));
}
/* Insert a PTE, top-level function is out of line. It uses an inline
* low level function in the respective pgtable-* files
*/
extern void set_pte_at(struct mm_struct *mm, unsigned long addr, pte_t *ptep,
pte_t pte);
/* This low level function performs the actual PTE insertion
* Setting the PTE depends on the MMU type and other factors. It's
* an horrible mess that I'm not going to try to clean up now but
* I'm keeping it in one place rather than spread around
*/
static inline void __set_pte_at(struct mm_struct *mm, unsigned long addr,
pte_t *ptep, pte_t pte, int percpu)
{
/* Second case is 32-bit with 64-bit PTE. In this case, we
* can just store as long as we do the two halves in the right order
* with a barrier in between.
* In the percpu case, we also fallback to the simple update
*/
if (IS_ENABLED(CONFIG_PPC32) && IS_ENABLED(CONFIG_PTE_64BIT) && !percpu) {
__asm__ __volatile__("\
stw%X0 %2,%0\n\
mbar\n\
stw%X1 %L2,%1"
: "=m" (*ptep), "=m" (*((unsigned char *)ptep+4))
: "r" (pte) : "memory");
return;
}
/* Anything else just stores the PTE normally. That covers all 64-bit
* cases, and 32-bit non-hash with 32-bit PTEs.
*/
#if defined(CONFIG_PPC_8xx) && defined(CONFIG_PPC_16K_PAGES)
ptep->pte = ptep->pte1 = ptep->pte2 = ptep->pte3 = pte_val(pte);
#else
*ptep = pte;
#endif
/*
* With hardware tablewalk, a sync is needed to ensure that
* subsequent accesses see the PTE we just wrote. Unlike userspace
* mappings, we can't tolerate spurious faults, so make sure
* the new PTE will be seen the first time.
*/
if (IS_ENABLED(CONFIG_PPC_BOOK3E_64) && is_kernel_addr(addr))
mb();
}
#define __HAVE_ARCH_PTEP_SET_ACCESS_FLAGS
extern int ptep_set_access_flags(struct vm_area_struct *vma, unsigned long address,
pte_t *ptep, pte_t entry, int dirty);
/*
* Macro to mark a page protection value as "uncacheable".
*/
#define _PAGE_CACHE_CTL (_PAGE_COHERENT | _PAGE_GUARDED | _PAGE_NO_CACHE | \
_PAGE_WRITETHRU)
#define pgprot_noncached(prot) (__pgprot((pgprot_val(prot) & ~_PAGE_CACHE_CTL) | \
_PAGE_NO_CACHE | _PAGE_GUARDED))
#define pgprot_noncached_wc(prot) (__pgprot((pgprot_val(prot) & ~_PAGE_CACHE_CTL) | \
_PAGE_NO_CACHE))
#define pgprot_cached(prot) (__pgprot((pgprot_val(prot) & ~_PAGE_CACHE_CTL) | \
_PAGE_COHERENT))
#if _PAGE_WRITETHRU != 0
#define pgprot_cached_wthru(prot) (__pgprot((pgprot_val(prot) & ~_PAGE_CACHE_CTL) | \
_PAGE_COHERENT | _PAGE_WRITETHRU))
#else
#define pgprot_cached_wthru(prot) pgprot_noncached(prot)
#endif
#define pgprot_cached_noncoherent(prot) \
(__pgprot(pgprot_val(prot) & ~_PAGE_CACHE_CTL))
#define pgprot_writecombine pgprot_noncached_wc
struct file;
extern pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
unsigned long size, pgprot_t vma_prot);
#define __HAVE_PHYS_MEM_ACCESS_PROT
#ifdef CONFIG_HUGETLB_PAGE
static inline int hugepd_ok(hugepd_t hpd)
{
#ifdef CONFIG_PPC_8xx
return ((hpd_val(hpd) & _PMD_PAGE_MASK) == _PMD_PAGE_8M);
#else
/* We clear the top bit to indicate hugepd */
return (hpd_val(hpd) && (hpd_val(hpd) & PD_HUGE) == 0);
#endif
}
static inline int pmd_huge(pmd_t pmd)
{
return 0;
}
static inline int pud_huge(pud_t pud)
{
return 0;
}
static inline int pgd_huge(pgd_t pgd)
{
return 0;
}
#define pgd_huge pgd_huge
#define is_hugepd(hpd) (hugepd_ok(hpd))
#endif
/*
* This gets called at the end of handling a page fault, when
* the kernel has put a new PTE into the page table for the process.
* We use it to ensure coherency between the i-cache and d-cache
* for the page which has just been mapped in.
*/
#if defined(CONFIG_PPC_FSL_BOOK3E) && defined(CONFIG_HUGETLB_PAGE)
void update_mmu_cache(struct vm_area_struct *vma, unsigned long address, pte_t *ptep);
#else
static inline
void update_mmu_cache(struct vm_area_struct *vma, unsigned long address, pte_t *ptep) {}
#endif
#endif /* __ASSEMBLY__ */
#endif
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