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Diffstat (limited to 'include/asm-generic/pgalloc.h')
| -rw-r--r-- | include/asm-generic/pgalloc.h | 215 |
1 files changed, 215 insertions, 0 deletions
diff --git a/include/asm-generic/pgalloc.h b/include/asm-generic/pgalloc.h new file mode 100644 index 0000000000..c75d4a7538 --- /dev/null +++ b/include/asm-generic/pgalloc.h @@ -0,0 +1,215 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef __ASM_GENERIC_PGALLOC_H +#define __ASM_GENERIC_PGALLOC_H + +#ifdef CONFIG_MMU + +#define GFP_PGTABLE_KERNEL (GFP_KERNEL | __GFP_ZERO) +#define GFP_PGTABLE_USER (GFP_PGTABLE_KERNEL | __GFP_ACCOUNT) + +/** + * __pte_alloc_one_kernel - allocate memory for a PTE-level kernel page table + * @mm: the mm_struct of the current context + * + * This function is intended for architectures that need + * anything beyond simple page allocation. + * + * Return: pointer to the allocated memory or %NULL on error + */ +static inline pte_t *__pte_alloc_one_kernel(struct mm_struct *mm) +{ + struct ptdesc *ptdesc = pagetable_alloc(GFP_PGTABLE_KERNEL & + ~__GFP_HIGHMEM, 0); + + if (!ptdesc) + return NULL; + return ptdesc_address(ptdesc); +} + +#ifndef __HAVE_ARCH_PTE_ALLOC_ONE_KERNEL +/** + * pte_alloc_one_kernel - allocate memory for a PTE-level kernel page table + * @mm: the mm_struct of the current context + * + * Return: pointer to the allocated memory or %NULL on error + */ +static inline pte_t *pte_alloc_one_kernel(struct mm_struct *mm) +{ + return __pte_alloc_one_kernel(mm); +} +#endif + +/** + * pte_free_kernel - free PTE-level kernel page table memory + * @mm: the mm_struct of the current context + * @pte: pointer to the memory containing the page table + */ +static inline void pte_free_kernel(struct mm_struct *mm, pte_t *pte) +{ + pagetable_free(virt_to_ptdesc(pte)); +} + +/** + * __pte_alloc_one - allocate memory for a PTE-level user page table + * @mm: the mm_struct of the current context + * @gfp: GFP flags to use for the allocation + * + * Allocate memory for a page table and ptdesc and runs pagetable_pte_ctor(). + * + * This function is intended for architectures that need + * anything beyond simple page allocation or must have custom GFP flags. + * + * Return: `struct page` referencing the ptdesc or %NULL on error + */ +static inline pgtable_t __pte_alloc_one(struct mm_struct *mm, gfp_t gfp) +{ + struct ptdesc *ptdesc; + + ptdesc = pagetable_alloc(gfp, 0); + if (!ptdesc) + return NULL; + if (!pagetable_pte_ctor(ptdesc)) { + pagetable_free(ptdesc); + return NULL; + } + + return ptdesc_page(ptdesc); +} + +#ifndef __HAVE_ARCH_PTE_ALLOC_ONE +/** + * pte_alloc_one - allocate a page for PTE-level user page table + * @mm: the mm_struct of the current context + * + * Allocate memory for a page table and ptdesc and runs pagetable_pte_ctor(). + * + * Return: `struct page` referencing the ptdesc or %NULL on error + */ +static inline pgtable_t pte_alloc_one(struct mm_struct *mm) +{ + return __pte_alloc_one(mm, GFP_PGTABLE_USER); +} +#endif + +/* + * Should really implement gc for free page table pages. This could be + * done with a reference count in struct page. + */ + +/** + * pte_free - free PTE-level user page table memory + * @mm: the mm_struct of the current context + * @pte_page: the `struct page` referencing the ptdesc + */ +static inline void pte_free(struct mm_struct *mm, struct page *pte_page) +{ + struct ptdesc *ptdesc = page_ptdesc(pte_page); + + pagetable_pte_dtor(ptdesc); + pagetable_free(ptdesc); +} + + +#if CONFIG_PGTABLE_LEVELS > 2 + +#ifndef __HAVE_ARCH_PMD_ALLOC_ONE +/** + * pmd_alloc_one - allocate memory for a PMD-level page table + * @mm: the mm_struct of the current context + * + * Allocate memory for a page table and ptdesc and runs pagetable_pmd_ctor(). + * + * Allocations use %GFP_PGTABLE_USER in user context and + * %GFP_PGTABLE_KERNEL in kernel context. + * + * Return: pointer to the allocated memory or %NULL on error + */ +static inline pmd_t *pmd_alloc_one(struct mm_struct *mm, unsigned long addr) +{ + struct ptdesc *ptdesc; + gfp_t gfp = GFP_PGTABLE_USER; + + if (mm == &init_mm) + gfp = GFP_PGTABLE_KERNEL; + ptdesc = pagetable_alloc(gfp, 0); + if (!ptdesc) + return NULL; + if (!pagetable_pmd_ctor(ptdesc)) { + pagetable_free(ptdesc); + return NULL; + } + return ptdesc_address(ptdesc); +} +#endif + +#ifndef __HAVE_ARCH_PMD_FREE +static inline void pmd_free(struct mm_struct *mm, pmd_t *pmd) +{ + struct ptdesc *ptdesc = virt_to_ptdesc(pmd); + + BUG_ON((unsigned long)pmd & (PAGE_SIZE-1)); + pagetable_pmd_dtor(ptdesc); + pagetable_free(ptdesc); +} +#endif + +#endif /* CONFIG_PGTABLE_LEVELS > 2 */ + +#if CONFIG_PGTABLE_LEVELS > 3 + +static inline pud_t *__pud_alloc_one(struct mm_struct *mm, unsigned long addr) +{ + gfp_t gfp = GFP_PGTABLE_USER; + struct ptdesc *ptdesc; + + if (mm == &init_mm) + gfp = GFP_PGTABLE_KERNEL; + gfp &= ~__GFP_HIGHMEM; + + ptdesc = pagetable_alloc(gfp, 0); + if (!ptdesc) + return NULL; + return ptdesc_address(ptdesc); +} + +#ifndef __HAVE_ARCH_PUD_ALLOC_ONE +/** + * pud_alloc_one - allocate memory for a PUD-level page table + * @mm: the mm_struct of the current context + * + * Allocate memory for a page table using %GFP_PGTABLE_USER for user context + * and %GFP_PGTABLE_KERNEL for kernel context. + * + * Return: pointer to the allocated memory or %NULL on error + */ +static inline pud_t *pud_alloc_one(struct mm_struct *mm, unsigned long addr) +{ + return __pud_alloc_one(mm, addr); +} +#endif + +static inline void __pud_free(struct mm_struct *mm, pud_t *pud) +{ + BUG_ON((unsigned long)pud & (PAGE_SIZE-1)); + pagetable_free(virt_to_ptdesc(pud)); +} + +#ifndef __HAVE_ARCH_PUD_FREE +static inline void pud_free(struct mm_struct *mm, pud_t *pud) +{ + __pud_free(mm, pud); +} +#endif + +#endif /* CONFIG_PGTABLE_LEVELS > 3 */ + +#ifndef __HAVE_ARCH_PGD_FREE +static inline void pgd_free(struct mm_struct *mm, pgd_t *pgd) +{ + pagetable_free(virt_to_ptdesc(pgd)); +} +#endif + +#endif /* CONFIG_MMU */ + +#endif /* __ASM_GENERIC_PGALLOC_H */ |