arch/powerpc/include/asm/book3s/64/pgalloc.h

Source file repositories/reference/linux-study-clean/arch/powerpc/include/asm/book3s/64/pgalloc.h

File Facts

System
Linux kernel
Corpus path
arch/powerpc/include/asm/book3s/64/pgalloc.h
Extension
.h
Size
4815 bytes
Lines
184
Domain
Architecture Layer
Bucket
arch/powerpc
Inferred role
Architecture Layer: implementation source
Status
source implementation candidate

Why This File Exists

CPU and platform-specific kernel glue: boot entry, traps, syscall entry, interrupts, page tables, context switch, and low-level barriers.

Dependency Surface

Detected Declarations

Annotated Snippet

struct vmemmap_backing {
	struct vmemmap_backing *list;
	unsigned long phys;
	unsigned long virt_addr;
};
extern struct vmemmap_backing *vmemmap_list;

extern pmd_t *pmd_fragment_alloc(struct mm_struct *, unsigned long);
extern void pmd_fragment_free(unsigned long *);
extern void pgtable_free_tlb(struct mmu_gather *tlb, void *table, int shift);
extern void __tlb_remove_table(void *_table);
void pte_frag_destroy(void *pte_frag);

static inline pgd_t *radix__pgd_alloc(struct mm_struct *mm)
{
#ifdef CONFIG_PPC_64K_PAGES
	return (pgd_t *)__get_free_page(pgtable_gfp_flags(mm, PGALLOC_GFP));
#else
	struct page *page;
	page = alloc_pages(pgtable_gfp_flags(mm, PGALLOC_GFP | __GFP_RETRY_MAYFAIL),
				4);
	if (!page)
		return NULL;
	return (pgd_t *) page_address(page);
#endif
}

static inline void radix__pgd_free(struct mm_struct *mm, pgd_t *pgd)
{
#ifdef CONFIG_PPC_64K_PAGES
	free_page((unsigned long)pgd);
#else
	free_pages((unsigned long)pgd, 4);
#endif
}

static inline pgd_t *pgd_alloc(struct mm_struct *mm)
{
	pgd_t *pgd;

	if (radix_enabled())
		return radix__pgd_alloc(mm);

	pgd = kmem_cache_alloc(PGT_CACHE(PGD_INDEX_SIZE),
			       pgtable_gfp_flags(mm, GFP_KERNEL));
	if (unlikely(!pgd))
		return pgd;

	/*
	 * Don't scan the PGD for pointers, it contains references to PUDs but
	 * those references are not full pointers and so can't be recognised by
	 * kmemleak.
	 */
	kmemleak_no_scan(pgd);

	/*
	 * With hugetlb, we don't clear the second half of the page table.
	 * If we share the same slab cache with the pmd or pud level table,
	 * we need to make sure we zero out the full table on alloc.
	 * With 4K we don't store slot in the second half. Hence we don't
	 * need to do this for 4k.
	 */
#if defined(CONFIG_HUGETLB_PAGE) && defined(CONFIG_PPC_64K_PAGES) && \
	(H_PGD_INDEX_SIZE == H_PUD_CACHE_INDEX)
	memset(pgd, 0, PGD_TABLE_SIZE);
#endif
	return pgd;
}

static inline void pgd_free(struct mm_struct *mm, pgd_t *pgd)
{
	if (radix_enabled())
		return radix__pgd_free(mm, pgd);
	kmem_cache_free(PGT_CACHE(PGD_INDEX_SIZE), pgd);
}

static inline void p4d_populate(struct mm_struct *mm, p4d_t *pgd, pud_t *pud)
{
	*pgd =  __p4d(__pgtable_ptr_val(pud) | PGD_VAL_BITS);
}

static inline pud_t *pud_alloc_one(struct mm_struct *mm, unsigned long addr)
{
	pud_t *pud;

	pud = kmem_cache_alloc(PGT_CACHE(PUD_CACHE_INDEX),
			       pgtable_gfp_flags(mm, GFP_KERNEL));
	/*
	 * Tell kmemleak to ignore the PUD, that means don't scan it for
	 * pointers and don't consider it a leak. PUDs are typically only

Annotation

Implementation Notes