| #ifndef _ASM_GENERIC_PGTABLE_H |
| #define _ASM_GENERIC_PGTABLE_H |
| |
| #ifndef __ASSEMBLY__ |
| #ifdef CONFIG_MMU |
| |
| #include <linux/mm_types.h> |
| #include <linux/bug.h> |
| |
| /* |
| * On almost all architectures and configurations, 0 can be used as the |
| * upper ceiling to free_pgtables(): on many architectures it has the same |
| * effect as using TASK_SIZE. However, there is one configuration which |
| * must impose a more careful limit, to avoid freeing kernel pgtables. |
| */ |
| #ifndef USER_PGTABLES_CEILING |
| #define USER_PGTABLES_CEILING 0UL |
| #endif |
| |
| #ifndef __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); |
| #endif |
| |
| #ifndef __HAVE_ARCH_PMDP_SET_ACCESS_FLAGS |
| extern int pmdp_set_access_flags(struct vm_area_struct *vma, |
| unsigned long address, pmd_t *pmdp, |
| pmd_t entry, int dirty); |
| #endif |
| |
| #ifndef __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG |
| static inline int ptep_test_and_clear_young(struct vm_area_struct *vma, |
| unsigned long address, |
| pte_t *ptep) |
| { |
| pte_t pte = *ptep; |
| int r = 1; |
| if (!pte_young(pte)) |
| r = 0; |
| else |
| set_pte_at(vma->vm_mm, address, ptep, pte_mkold(pte)); |
| return r; |
| } |
| #endif |
| |
| #ifndef __HAVE_ARCH_PMDP_TEST_AND_CLEAR_YOUNG |
| #ifdef CONFIG_TRANSPARENT_HUGEPAGE |
| static inline int pmdp_test_and_clear_young(struct vm_area_struct *vma, |
| unsigned long address, |
| pmd_t *pmdp) |
| { |
| pmd_t pmd = *pmdp; |
| int r = 1; |
| if (!pmd_young(pmd)) |
| r = 0; |
| else |
| set_pmd_at(vma->vm_mm, address, pmdp, pmd_mkold(pmd)); |
| return r; |
| } |
| #else /* CONFIG_TRANSPARENT_HUGEPAGE */ |
| static inline int pmdp_test_and_clear_young(struct vm_area_struct *vma, |
| unsigned long address, |
| pmd_t *pmdp) |
| { |
| BUG(); |
| return 0; |
| } |
| #endif /* CONFIG_TRANSPARENT_HUGEPAGE */ |
| #endif |
| |
| #ifndef __HAVE_ARCH_PTEP_CLEAR_YOUNG_FLUSH |
| int ptep_clear_flush_young(struct vm_area_struct *vma, |
| unsigned long address, pte_t *ptep); |
| #endif |
| |
| #ifndef __HAVE_ARCH_PMDP_CLEAR_YOUNG_FLUSH |
| int pmdp_clear_flush_young(struct vm_area_struct *vma, |
| unsigned long address, pmd_t *pmdp); |
| #endif |
| |
| #ifndef __HAVE_ARCH_PTEP_GET_AND_CLEAR |
| static inline pte_t ptep_get_and_clear(struct mm_struct *mm, |
| unsigned long address, |
| pte_t *ptep) |
| { |
| pte_t pte = *ptep; |
| pte_clear(mm, address, ptep); |
| return pte; |
| } |
| #endif |
| |
| #ifndef __HAVE_ARCH_PMDP_GET_AND_CLEAR |
| #ifdef CONFIG_TRANSPARENT_HUGEPAGE |
| static inline pmd_t pmdp_get_and_clear(struct mm_struct *mm, |
| unsigned long address, |
| pmd_t *pmdp) |
| { |
| pmd_t pmd = *pmdp; |
| pmd_clear(pmdp); |
| return pmd; |
| } |
| #endif /* CONFIG_TRANSPARENT_HUGEPAGE */ |
| #endif |
| |
| #ifndef __HAVE_ARCH_PTEP_GET_AND_CLEAR_FULL |
| static inline pte_t ptep_get_and_clear_full(struct mm_struct *mm, |
| unsigned long address, pte_t *ptep, |
| int full) |
| { |
| pte_t pte; |
| pte = ptep_get_and_clear(mm, address, ptep); |
| return pte; |
| } |
| #endif |
| |
| /* |
| * Some architectures may be able to avoid expensive synchronization |
| * primitives when modifications are made to PTE's which are already |
| * not present, or in the process of an address space destruction. |
| */ |
| #ifndef __HAVE_ARCH_PTE_CLEAR_NOT_PRESENT_FULL |
| static inline void pte_clear_not_present_full(struct mm_struct *mm, |
| unsigned long address, |
| pte_t *ptep, |
| int full) |
| { |
| pte_clear(mm, address, ptep); |
| } |
| #endif |
| |
| #ifndef __HAVE_ARCH_PTEP_CLEAR_FLUSH |
| extern pte_t ptep_clear_flush(struct vm_area_struct *vma, |
| unsigned long address, |
| pte_t *ptep); |
| #endif |
| |
| #ifndef __HAVE_ARCH_PMDP_CLEAR_FLUSH |
| extern pmd_t pmdp_clear_flush(struct vm_area_struct *vma, |
| unsigned long address, |
| pmd_t *pmdp); |
| #endif |
| |
| #ifndef __HAVE_ARCH_PTEP_SET_WRPROTECT |
| struct mm_struct; |
| static inline void ptep_set_wrprotect(struct mm_struct *mm, unsigned long address, pte_t *ptep) |
| { |
| pte_t old_pte = *ptep; |
| set_pte_at(mm, address, ptep, pte_wrprotect(old_pte)); |
| } |
| #endif |
| |
| #ifndef __HAVE_ARCH_PMDP_SET_WRPROTECT |
| #ifdef CONFIG_TRANSPARENT_HUGEPAGE |
| static inline void pmdp_set_wrprotect(struct mm_struct *mm, |
| unsigned long address, pmd_t *pmdp) |
| { |
| pmd_t old_pmd = *pmdp; |
| set_pmd_at(mm, address, pmdp, pmd_wrprotect(old_pmd)); |
| } |
| #else /* CONFIG_TRANSPARENT_HUGEPAGE */ |
| static inline void pmdp_set_wrprotect(struct mm_struct *mm, |
| unsigned long address, pmd_t *pmdp) |
| { |
| BUG(); |
| } |
| #endif /* CONFIG_TRANSPARENT_HUGEPAGE */ |
| #endif |
| |
| #ifndef __HAVE_ARCH_PMDP_SPLITTING_FLUSH |
| extern void pmdp_splitting_flush(struct vm_area_struct *vma, |
| unsigned long address, pmd_t *pmdp); |
| #endif |
| |
| #ifndef __HAVE_ARCH_PGTABLE_DEPOSIT |
| extern void pgtable_trans_huge_deposit(struct mm_struct *mm, pmd_t *pmdp, |
| pgtable_t pgtable); |
| #endif |
| |
| #ifndef __HAVE_ARCH_PGTABLE_WITHDRAW |
| extern pgtable_t pgtable_trans_huge_withdraw(struct mm_struct *mm, pmd_t *pmdp); |
| #endif |
| |
| #ifndef __HAVE_ARCH_PMDP_INVALIDATE |
| extern void pmdp_invalidate(struct vm_area_struct *vma, unsigned long address, |
| pmd_t *pmdp); |
| #endif |
| |
| #ifndef __HAVE_ARCH_PTE_SAME |
| static inline int pte_same(pte_t pte_a, pte_t pte_b) |
| { |
| return pte_val(pte_a) == pte_val(pte_b); |
| } |
| #endif |
| |
| #ifndef __HAVE_ARCH_PTE_UNUSED |
| /* |
| * Some architectures provide facilities to virtualization guests |
| * so that they can flag allocated pages as unused. This allows the |
| * host to transparently reclaim unused pages. This function returns |
| * whether the pte's page is unused. |
| */ |
| static inline int pte_unused(pte_t pte) |
| { |
| return 0; |
| } |
| #endif |
| |
| #ifndef __HAVE_ARCH_PMD_SAME |
| #ifdef CONFIG_TRANSPARENT_HUGEPAGE |
| static inline int pmd_same(pmd_t pmd_a, pmd_t pmd_b) |
| { |
| return pmd_val(pmd_a) == pmd_val(pmd_b); |
| } |
| #else /* CONFIG_TRANSPARENT_HUGEPAGE */ |
| static inline int pmd_same(pmd_t pmd_a, pmd_t pmd_b) |
| { |
| BUG(); |
| return 0; |
| } |
| #endif /* CONFIG_TRANSPARENT_HUGEPAGE */ |
| #endif |
| |
| #ifndef __HAVE_ARCH_PGD_OFFSET_GATE |
| #define pgd_offset_gate(mm, addr) pgd_offset(mm, addr) |
| #endif |
| |
| #ifndef __HAVE_ARCH_MOVE_PTE |
| #define move_pte(pte, prot, old_addr, new_addr) (pte) |
| #endif |
| |
| #ifndef pte_accessible |
| # define pte_accessible(mm, pte) ((void)(pte), 1) |
| #endif |
| |
| #ifndef pte_present_nonuma |
| #define pte_present_nonuma(pte) pte_present(pte) |
| #endif |
| |
| #ifndef flush_tlb_fix_spurious_fault |
| #define flush_tlb_fix_spurious_fault(vma, address) flush_tlb_page(vma, address) |
| #endif |
| |
| #ifndef pgprot_noncached |
| #define pgprot_noncached(prot) (prot) |
| #endif |
| |
| #ifndef pgprot_writecombine |
| #define pgprot_writecombine pgprot_noncached |
| #endif |
| |
| #ifndef pgprot_device |
| #define pgprot_device pgprot_noncached |
| #endif |
| |
| #ifndef pgprot_modify |
| #define pgprot_modify pgprot_modify |
| static inline pgprot_t pgprot_modify(pgprot_t oldprot, pgprot_t newprot) |
| { |
| if (pgprot_val(oldprot) == pgprot_val(pgprot_noncached(oldprot))) |
| newprot = pgprot_noncached(newprot); |
| if (pgprot_val(oldprot) == pgprot_val(pgprot_writecombine(oldprot))) |
| newprot = pgprot_writecombine(newprot); |
| if (pgprot_val(oldprot) == pgprot_val(pgprot_device(oldprot))) |
| newprot = pgprot_device(newprot); |
| return newprot; |
| } |
| #endif |
| |
| /* |
| * When walking page tables, get the address of the next boundary, |
| * or the end address of the range if that comes earlier. Although no |
| * vma end wraps to 0, rounded up __boundary may wrap to 0 throughout. |
| */ |
| |
| #define pgd_addr_end(addr, end) \ |
| ({ unsigned long __boundary = ((addr) + PGDIR_SIZE) & PGDIR_MASK; \ |
| (__boundary - 1 < (end) - 1)? __boundary: (end); \ |
| }) |
| |
| #ifndef pud_addr_end |
| #define pud_addr_end(addr, end) \ |
| ({ unsigned long __boundary = ((addr) + PUD_SIZE) & PUD_MASK; \ |
| (__boundary - 1 < (end) - 1)? __boundary: (end); \ |
| }) |
| #endif |
| |
| #ifndef pmd_addr_end |
| #define pmd_addr_end(addr, end) \ |
| ({ unsigned long __boundary = ((addr) + PMD_SIZE) & PMD_MASK; \ |
| (__boundary - 1 < (end) - 1)? __boundary: (end); \ |
| }) |
| #endif |
| |
| /* |
| * When walking page tables, we usually want to skip any p?d_none entries; |
| * and any p?d_bad entries - reporting the error before resetting to none. |
| * Do the tests inline, but report and clear the bad entry in mm/memory.c. |
| */ |
| void pgd_clear_bad(pgd_t *); |
| void pud_clear_bad(pud_t *); |
| void pmd_clear_bad(pmd_t *); |
| |
| static inline int pgd_none_or_clear_bad(pgd_t *pgd) |
| { |
| if (pgd_none(*pgd)) |
| return 1; |
| if (unlikely(pgd_bad(*pgd))) { |
| pgd_clear_bad(pgd); |
| return 1; |
| } |
| return 0; |
| } |
| |
| static inline int pud_none_or_clear_bad(pud_t *pud) |
| { |
| if (pud_none(*pud)) |
| return 1; |
| if (unlikely(pud_bad(*pud))) { |
| pud_clear_bad(pud); |
| return 1; |
| } |
| return 0; |
| } |
| |
| static inline int pmd_none_or_clear_bad(pmd_t *pmd) |
| { |
| if (pmd_none(*pmd)) |
| return 1; |
| if (unlikely(pmd_bad(*pmd))) { |
| pmd_clear_bad(pmd); |
| return 1; |
| } |
| return 0; |
| } |
| |
| static inline pte_t __ptep_modify_prot_start(struct mm_struct *mm, |
| unsigned long addr, |
| pte_t *ptep) |
| { |
| /* |
| * Get the current pte state, but zero it out to make it |
| * non-present, preventing the hardware from asynchronously |
| * updating it. |
| */ |
| return ptep_get_and_clear(mm, addr, ptep); |
| } |
| |
| static inline void __ptep_modify_prot_commit(struct mm_struct *mm, |
| unsigned long addr, |
| pte_t *ptep, pte_t pte) |
| { |
| /* |
| * The pte is non-present, so there's no hardware state to |
| * preserve. |
| */ |
| set_pte_at(mm, addr, ptep, pte); |
| } |
| |
| #ifndef __HAVE_ARCH_PTEP_MODIFY_PROT_TRANSACTION |
| /* |
| * Start a pte protection read-modify-write transaction, which |
| * protects against asynchronous hardware modifications to the pte. |
| * The intention is not to prevent the hardware from making pte |
| * updates, but to prevent any updates it may make from being lost. |
| * |
| * This does not protect against other software modifications of the |
| * pte; the appropriate pte lock must be held over the transation. |
| * |
| * Note that this interface is intended to be batchable, meaning that |
| * ptep_modify_prot_commit may not actually update the pte, but merely |
| * queue the update to be done at some later time. The update must be |
| * actually committed before the pte lock is released, however. |
| */ |
| static inline pte_t ptep_modify_prot_start(struct mm_struct *mm, |
| unsigned long addr, |
| pte_t *ptep) |
| { |
| return __ptep_modify_prot_start(mm, addr, ptep); |
| } |
| |
| /* |
| * Commit an update to a pte, leaving any hardware-controlled bits in |
| * the PTE unmodified. |
| */ |
| static inline void ptep_modify_prot_commit(struct mm_struct *mm, |
| unsigned long addr, |
| pte_t *ptep, pte_t pte) |
| { |
| __ptep_modify_prot_commit(mm, addr, ptep, pte); |
| } |
| #endif /* __HAVE_ARCH_PTEP_MODIFY_PROT_TRANSACTION */ |
| #endif /* CONFIG_MMU */ |
| |
| /* |
| * A facility to provide lazy MMU batching. This allows PTE updates and |
| * page invalidations to be delayed until a call to leave lazy MMU mode |
| * is issued. Some architectures may benefit from doing this, and it is |
| * beneficial for both shadow and direct mode hypervisors, which may batch |
| * the PTE updates which happen during this window. Note that using this |
| * interface requires that read hazards be removed from the code. A read |
| * hazard could result in the direct mode hypervisor case, since the actual |
| * write to the page tables may not yet have taken place, so reads though |
| * a raw PTE pointer after it has been modified are not guaranteed to be |
| * up to date. This mode can only be entered and left under the protection of |
| * the page table locks for all page tables which may be modified. In the UP |
| * case, this is required so that preemption is disabled, and in the SMP case, |
| * it must synchronize the delayed page table writes properly on other CPUs. |
| */ |
| #ifndef __HAVE_ARCH_ENTER_LAZY_MMU_MODE |
| #define arch_enter_lazy_mmu_mode() do {} while (0) |
| #define arch_leave_lazy_mmu_mode() do {} while (0) |
| #define arch_flush_lazy_mmu_mode() do {} while (0) |
| #endif |
| |
| /* |
| * A facility to provide batching of the reload of page tables and |
| * other process state with the actual context switch code for |
| * paravirtualized guests. By convention, only one of the batched |
| * update (lazy) modes (CPU, MMU) should be active at any given time, |
| * entry should never be nested, and entry and exits should always be |
| * paired. This is for sanity of maintaining and reasoning about the |
| * kernel code. In this case, the exit (end of the context switch) is |
| * in architecture-specific code, and so doesn't need a generic |
| * definition. |
| */ |
| #ifndef __HAVE_ARCH_START_CONTEXT_SWITCH |
| #define arch_start_context_switch(prev) do {} while (0) |
| #endif |
| |
| #ifndef CONFIG_HAVE_ARCH_SOFT_DIRTY |
| static inline int pte_soft_dirty(pte_t pte) |
| { |
| return 0; |
| } |
| |
| static inline int pmd_soft_dirty(pmd_t pmd) |
| { |
| return 0; |
| } |
| |
| static inline pte_t pte_mksoft_dirty(pte_t pte) |
| { |
| return pte; |
| } |
| |
| static inline pmd_t pmd_mksoft_dirty(pmd_t pmd) |
| { |
| return pmd; |
| } |
| |
| static inline pte_t pte_swp_mksoft_dirty(pte_t pte) |
| { |
| return pte; |
| } |
| |
| static inline int pte_swp_soft_dirty(pte_t pte) |
| { |
| return 0; |
| } |
| |
| static inline pte_t pte_swp_clear_soft_dirty(pte_t pte) |
| { |
| return pte; |
| } |
| |
| static inline pte_t pte_file_clear_soft_dirty(pte_t pte) |
| { |
| return pte; |
| } |
| |
| static inline pte_t pte_file_mksoft_dirty(pte_t pte) |
| { |
| return pte; |
| } |
| |
| static inline int pte_file_soft_dirty(pte_t pte) |
| { |
| return 0; |
| } |
| #endif |
| |
| #ifndef __HAVE_PFNMAP_TRACKING |
| /* |
| * Interfaces that can be used by architecture code to keep track of |
| * memory type of pfn mappings specified by the remap_pfn_range, |
| * vm_insert_pfn. |
| */ |
| |
| /* |
| * track_pfn_remap is called when a _new_ pfn mapping is being established |
| * by remap_pfn_range() for physical range indicated by pfn and size. |
| */ |
| static inline int track_pfn_remap(struct vm_area_struct *vma, pgprot_t *prot, |
| unsigned long pfn, unsigned long addr, |
| unsigned long size) |
| { |
| return 0; |
| } |
| |
| /* |
| * track_pfn_insert is called when a _new_ single pfn is established |
| * by vm_insert_pfn(). |
| */ |
| static inline int track_pfn_insert(struct vm_area_struct *vma, pgprot_t *prot, |
| unsigned long pfn) |
| { |
| return 0; |
| } |
| |
| /* |
| * track_pfn_copy is called when vma that is covering the pfnmap gets |
| * copied through copy_page_range(). |
| */ |
| static inline int track_pfn_copy(struct vm_area_struct *vma) |
| { |
| return 0; |
| } |
| |
| /* |
| * untrack_pfn_vma is called while unmapping a pfnmap for a region. |
| * untrack can be called for a specific region indicated by pfn and size or |
| * can be for the entire vma (in which case pfn, size are zero). |
| */ |
| static inline void untrack_pfn(struct vm_area_struct *vma, |
| unsigned long pfn, unsigned long size) |
| { |
| } |
| #else |
| extern int track_pfn_remap(struct vm_area_struct *vma, pgprot_t *prot, |
| unsigned long pfn, unsigned long addr, |
| unsigned long size); |
| extern int track_pfn_insert(struct vm_area_struct *vma, pgprot_t *prot, |
| unsigned long pfn); |
| extern int track_pfn_copy(struct vm_area_struct *vma); |
| extern void untrack_pfn(struct vm_area_struct *vma, unsigned long pfn, |
| unsigned long size); |
| #endif |
| |
| #ifdef __HAVE_COLOR_ZERO_PAGE |
| static inline int is_zero_pfn(unsigned long pfn) |
| { |
| extern unsigned long zero_pfn; |
| unsigned long offset_from_zero_pfn = pfn - zero_pfn; |
| return offset_from_zero_pfn <= (zero_page_mask >> PAGE_SHIFT); |
| } |
| |
| #define my_zero_pfn(addr) page_to_pfn(ZERO_PAGE(addr)) |
| |
| #else |
| static inline int is_zero_pfn(unsigned long pfn) |
| { |
| extern unsigned long zero_pfn; |
| return pfn == zero_pfn; |
| } |
| |
| static inline unsigned long my_zero_pfn(unsigned long addr) |
| { |
| extern unsigned long zero_pfn; |
| return zero_pfn; |
| } |
| #endif |
| |
| #ifdef CONFIG_MMU |
| |
| #ifndef CONFIG_TRANSPARENT_HUGEPAGE |
| static inline int pmd_trans_huge(pmd_t pmd) |
| { |
| return 0; |
| } |
| static inline int pmd_trans_splitting(pmd_t pmd) |
| { |
| return 0; |
| } |
| #ifndef __HAVE_ARCH_PMD_WRITE |
| static inline int pmd_write(pmd_t pmd) |
| { |
| BUG(); |
| return 0; |
| } |
| #endif /* __HAVE_ARCH_PMD_WRITE */ |
| #endif /* CONFIG_TRANSPARENT_HUGEPAGE */ |
| |
| #ifndef pmd_read_atomic |
| static inline pmd_t pmd_read_atomic(pmd_t *pmdp) |
| { |
| /* |
| * Depend on compiler for an atomic pmd read. NOTE: this is |
| * only going to work, if the pmdval_t isn't larger than |
| * an unsigned long. |
| */ |
| return *pmdp; |
| } |
| #endif |
| |
| #ifndef pmd_move_must_withdraw |
| static inline int pmd_move_must_withdraw(spinlock_t *new_pmd_ptl, |
| spinlock_t *old_pmd_ptl) |
| { |
| /* |
| * With split pmd lock we also need to move preallocated |
| * PTE page table if new_pmd is on different PMD page table. |
| */ |
| return new_pmd_ptl != old_pmd_ptl; |
| } |
| #endif |
| |
| /* |
| * This function is meant to be used by sites walking pagetables with |
| * the mmap_sem hold in read mode to protect against MADV_DONTNEED and |
| * transhuge page faults. MADV_DONTNEED can convert a transhuge pmd |
| * into a null pmd and the transhuge page fault can convert a null pmd |
| * into an hugepmd or into a regular pmd (if the hugepage allocation |
| * fails). While holding the mmap_sem in read mode the pmd becomes |
| * stable and stops changing under us only if it's not null and not a |
| * transhuge pmd. When those races occurs and this function makes a |
| * difference vs the standard pmd_none_or_clear_bad, the result is |
| * undefined so behaving like if the pmd was none is safe (because it |
| * can return none anyway). The compiler level barrier() is critically |
| * important to compute the two checks atomically on the same pmdval. |
| * |
| * For 32bit kernels with a 64bit large pmd_t this automatically takes |
| * care of reading the pmd atomically to avoid SMP race conditions |
| * against pmd_populate() when the mmap_sem is hold for reading by the |
| * caller (a special atomic read not done by "gcc" as in the generic |
| * version above, is also needed when THP is disabled because the page |
| * fault can populate the pmd from under us). |
| */ |
| static inline int pmd_none_or_trans_huge_or_clear_bad(pmd_t *pmd) |
| { |
| pmd_t pmdval = pmd_read_atomic(pmd); |
| /* |
| * The barrier will stabilize the pmdval in a register or on |
| * the stack so that it will stop changing under the code. |
| * |
| * When CONFIG_TRANSPARENT_HUGEPAGE=y on x86 32bit PAE, |
| * pmd_read_atomic is allowed to return a not atomic pmdval |
| * (for example pointing to an hugepage that has never been |
| * mapped in the pmd). The below checks will only care about |
| * the low part of the pmd with 32bit PAE x86 anyway, with the |
| * exception of pmd_none(). So the important thing is that if |
| * the low part of the pmd is found null, the high part will |
| * be also null or the pmd_none() check below would be |
| * confused. |
| */ |
| #ifdef CONFIG_TRANSPARENT_HUGEPAGE |
| barrier(); |
| #endif |
| if (pmd_none(pmdval) || pmd_trans_huge(pmdval)) |
| return 1; |
| if (unlikely(pmd_bad(pmdval))) { |
| pmd_clear_bad(pmd); |
| return 1; |
| } |
| return 0; |
| } |
| |
| /* |
| * This is a noop if Transparent Hugepage Support is not built into |
| * the kernel. Otherwise it is equivalent to |
| * pmd_none_or_trans_huge_or_clear_bad(), and shall only be called in |
| * places that already verified the pmd is not none and they want to |
| * walk ptes while holding the mmap sem in read mode (write mode don't |
| * need this). If THP is not enabled, the pmd can't go away under the |
| * code even if MADV_DONTNEED runs, but if THP is enabled we need to |
| * run a pmd_trans_unstable before walking the ptes after |
| * split_huge_page_pmd returns (because it may have run when the pmd |
| * become null, but then a page fault can map in a THP and not a |
| * regular page). |
| */ |
| static inline int pmd_trans_unstable(pmd_t *pmd) |
| { |
| #ifdef CONFIG_TRANSPARENT_HUGEPAGE |
| return pmd_none_or_trans_huge_or_clear_bad(pmd); |
| #else |
| return 0; |
| #endif |
| } |
| |
| #ifdef CONFIG_NUMA_BALANCING |
| /* |
| * _PAGE_NUMA distinguishes between an unmapped page table entry, an entry that |
| * is protected for PROT_NONE and a NUMA hinting fault entry. If the |
| * architecture defines __PAGE_PROTNONE then it should take that into account |
| * but those that do not can rely on the fact that the NUMA hinting scanner |
| * skips inaccessible VMAs. |
| * |
| * pte/pmd_present() returns true if pte/pmd_numa returns true. Page |
| * fault triggers on those regions if pte/pmd_numa returns true |
| * (because _PAGE_PRESENT is not set). |
| */ |
| #ifndef pte_numa |
| static inline int pte_numa(pte_t pte) |
| { |
| return ptenuma_flags(pte) == _PAGE_NUMA; |
| } |
| #endif |
| |
| #ifndef pmd_numa |
| static inline int pmd_numa(pmd_t pmd) |
| { |
| return pmdnuma_flags(pmd) == _PAGE_NUMA; |
| } |
| #endif |
| |
| /* |
| * pte/pmd_mknuma sets the _PAGE_ACCESSED bitflag automatically |
| * because they're called by the NUMA hinting minor page fault. If we |
| * wouldn't set the _PAGE_ACCESSED bitflag here, the TLB miss handler |
| * would be forced to set it later while filling the TLB after we |
| * return to userland. That would trigger a second write to memory |
| * that we optimize away by setting _PAGE_ACCESSED here. |
| */ |
| #ifndef pte_mknonnuma |
| static inline pte_t pte_mknonnuma(pte_t pte) |
| { |
| pteval_t val = pte_val(pte); |
| |
| val &= ~_PAGE_NUMA; |
| val |= (_PAGE_PRESENT|_PAGE_ACCESSED); |
| return __pte(val); |
| } |
| #endif |
| |
| #ifndef pmd_mknonnuma |
| static inline pmd_t pmd_mknonnuma(pmd_t pmd) |
| { |
| pmdval_t val = pmd_val(pmd); |
| |
| val &= ~_PAGE_NUMA; |
| val |= (_PAGE_PRESENT|_PAGE_ACCESSED); |
| |
| return __pmd(val); |
| } |
| #endif |
| |
| #ifndef pte_mknuma |
| static inline pte_t pte_mknuma(pte_t pte) |
| { |
| pteval_t val = pte_val(pte); |
| |
| VM_BUG_ON(!(val & _PAGE_PRESENT)); |
| |
| val &= ~_PAGE_PRESENT; |
| val |= _PAGE_NUMA; |
| |
| return __pte(val); |
| } |
| #endif |
| |
| #ifndef ptep_set_numa |
| static inline void ptep_set_numa(struct mm_struct *mm, unsigned long addr, |
| pte_t *ptep) |
| { |
| pte_t ptent = *ptep; |
| |
| ptent = pte_mknuma(ptent); |
| set_pte_at(mm, addr, ptep, ptent); |
| return; |
| } |
| #endif |
| |
| #ifndef pmd_mknuma |
| static inline pmd_t pmd_mknuma(pmd_t pmd) |
| { |
| pmdval_t val = pmd_val(pmd); |
| |
| val &= ~_PAGE_PRESENT; |
| val |= _PAGE_NUMA; |
| |
| return __pmd(val); |
| } |
| #endif |
| |
| #ifndef pmdp_set_numa |
| static inline void pmdp_set_numa(struct mm_struct *mm, unsigned long addr, |
| pmd_t *pmdp) |
| { |
| pmd_t pmd = *pmdp; |
| |
| pmd = pmd_mknuma(pmd); |
| set_pmd_at(mm, addr, pmdp, pmd); |
| return; |
| } |
| #endif |
| #else |
| static inline int pmd_numa(pmd_t pmd) |
| { |
| return 0; |
| } |
| |
| static inline int pte_numa(pte_t pte) |
| { |
| return 0; |
| } |
| |
| static inline pte_t pte_mknonnuma(pte_t pte) |
| { |
| return pte; |
| } |
| |
| static inline pmd_t pmd_mknonnuma(pmd_t pmd) |
| { |
| return pmd; |
| } |
| |
| static inline pte_t pte_mknuma(pte_t pte) |
| { |
| return pte; |
| } |
| |
| static inline void ptep_set_numa(struct mm_struct *mm, unsigned long addr, |
| pte_t *ptep) |
| { |
| return; |
| } |
| |
| |
| static inline pmd_t pmd_mknuma(pmd_t pmd) |
| { |
| return pmd; |
| } |
| |
| static inline void pmdp_set_numa(struct mm_struct *mm, unsigned long addr, |
| pmd_t *pmdp) |
| { |
| return ; |
| } |
| #endif /* CONFIG_NUMA_BALANCING */ |
| |
| #endif /* CONFIG_MMU */ |
| |
| #endif /* !__ASSEMBLY__ */ |
| |
| #ifndef io_remap_pfn_range |
| #define io_remap_pfn_range remap_pfn_range |
| #endif |
| |
| #endif /* _ASM_GENERIC_PGTABLE_H */ |