[linux-2.6-block.git] / include / asm-generic / pgalloc.h

/* 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 a page for 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)
{
	return (pte_t *)__get_free_page(GFP_PGTABLE_KERNEL);
}

#ifndef __HAVE_ARCH_PTE_ALLOC_ONE_KERNEL
/**
 * pte_alloc_one_kernel - allocate a page for 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 page
 * @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)
{
	free_page((unsigned long)pte);
}

/**
 * __pte_alloc_one - allocate a page for PTE-level user page table
 * @mm: the mm_struct of the current context
 * @gfp: GFP flags to use for the allocation
 *
 * Allocates a page and runs the pgtable_pte_page_ctor().
 *
 * This function is intended for architectures that need
 * anything beyond simple page allocation or must have custom GFP flags.
 *
 * Return: `struct page` initialized as page table or %NULL on error
 */
static inline pgtable_t __pte_alloc_one(struct mm_struct *mm, gfp_t gfp)
{
	struct page *pte;

	pte = alloc_page(gfp);
	if (!pte)
		return NULL;
	if (!pgtable_pte_page_ctor(pte)) {
		__free_page(pte);
		return NULL;
	}

	return pte;
}

#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
 *
 * Allocates a page and runs the pgtable_pte_page_ctor().
 *
 * Return: `struct page` initialized as page table 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 page
 * @mm: the mm_struct of the current context
 * @pte_page: the `struct page` representing the page table
 */
static inline void pte_free(struct mm_struct *mm, struct page *pte_page)
{
	pgtable_pte_page_dtor(pte_page);
	__free_page(pte_page);
}

#endif /* CONFIG_MMU */

#endif /* __ASM_GENERIC_PGALLOC_H */
Commit	Line	Data
b2441318	1	/* SPDX-License-Identifier: GPL-2.0 */
5c01b46b AB	2	#ifndef __ASM_GENERIC_PGALLOC_H
5c01b46b AB	3	#define __ASM_GENERIC_PGALLOC_H
5fba4af4	4
5c01b46b	5	#ifdef CONFIG_MMU
5fba4af4 MR	6
	7	#define GFP_PGTABLE_KERNEL (GFP_KERNEL \| __GFP_ZERO)
	8	#define GFP_PGTABLE_USER (GFP_PGTABLE_KERNEL \| __GFP_ACCOUNT)
	9
	10	/**
	11	* __pte_alloc_one_kernel - allocate a page for PTE-level kernel page table
	12	* @mm: the mm_struct of the current context
	13	*
	14	* This function is intended for architectures that need
	15	* anything beyond simple page allocation.
	16	*
	17	* Return: pointer to the allocated memory or %NULL on error
	18	*/
	19	static inline pte_t __pte_alloc_one_kernel(struct mm_struct mm)
	20	{
	21	return (pte_t *)__get_free_page(GFP_PGTABLE_KERNEL);
	22	}
	23
	24	#ifndef __HAVE_ARCH_PTE_ALLOC_ONE_KERNEL
	25	/**
	26	* pte_alloc_one_kernel - allocate a page for PTE-level kernel page table
	27	* @mm: the mm_struct of the current context
	28	*
	29	* Return: pointer to the allocated memory or %NULL on error
	30	*/
	31	static inline pte_t pte_alloc_one_kernel(struct mm_struct mm)
	32	{
	33	return __pte_alloc_one_kernel(mm);
	34	}
	35	#endif
	36
	37	/**
	38	* pte_free_kernel - free PTE-level kernel page table page
	39	* @mm: the mm_struct of the current context
	40	* @pte: pointer to the memory containing the page table
	41	*/
	42	static inline void pte_free_kernel(struct mm_struct mm, pte_t pte)
	43	{
	44	free_page((unsigned long)pte);
	45	}
	46
	47	/**
	48	* __pte_alloc_one - allocate a page for PTE-level user page table
	49	* @mm: the mm_struct of the current context
	50	* @gfp: GFP flags to use for the allocation
	51	*
b4ed71f5	52	* Allocates a page and runs the pgtable_pte_page_ctor().
5fba4af4 MR	53	*
	54	* This function is intended for architectures that need
	55	* anything beyond simple page allocation or must have custom GFP flags.
	56	*
	57	* Return: `struct page` initialized as page table or %NULL on error
	58	*/
	59	static inline pgtable_t __pte_alloc_one(struct mm_struct *mm, gfp_t gfp)
	60	{
	61	struct page *pte;
	62
	63	pte = alloc_page(gfp);
	64	if (!pte)
	65	return NULL;
b4ed71f5	66	if (!pgtable_pte_page_ctor(pte)) {
5fba4af4 MR	67	__free_page(pte);
	68	return NULL;
	69	}
	70
	71	return pte;
	72	}
	73
	74	#ifndef __HAVE_ARCH_PTE_ALLOC_ONE
	75	/**
	76	* pte_alloc_one - allocate a page for PTE-level user page table
	77	* @mm: the mm_struct of the current context
	78	*
b4ed71f5	79	* Allocates a page and runs the pgtable_pte_page_ctor().
5fba4af4 MR	80	*
	81	* Return: `struct page` initialized as page table or %NULL on error
	82	*/
	83	static inline pgtable_t pte_alloc_one(struct mm_struct *mm)
	84	{
	85	return __pte_alloc_one(mm, GFP_PGTABLE_USER);
	86	}
5c01b46b AB	87	#endif
5c01b46b AB	88
5fba4af4 MR	89	/*
	90	* Should really implement gc for free page table pages. This could be
	91	* done with a reference count in struct page.
	92	*/
	93
	94	/**
	95	* pte_free - free PTE-level user page table page
	96	* @mm: the mm_struct of the current context
	97	* @pte_page: the `struct page` representing the page table
	98	*/
	99	static inline void pte_free(struct mm_struct mm, struct page pte_page)
	100	{
b4ed71f5	101	pgtable_pte_page_dtor(pte_page);
5fba4af4 MR	102	__free_page(pte_page);
	103	}
	104
5fba4af4 MR	105	#endif /* CONFIG_MMU */
5fba4af4 MR	106
5c01b46b	107	#endif /* __ASM_GENERIC_PGALLOC_H */