diff options
Diffstat (limited to 'arch/powerpc/include')
| -rw-r--r-- | arch/powerpc/include/asm/pte-walk.h | 29 |
1 files changed, 29 insertions, 0 deletions
diff --git a/arch/powerpc/include/asm/pte-walk.h b/arch/powerpc/include/asm/pte-walk.h index 33fa5dd8ee6a..714a35f0d425 100644 --- a/arch/powerpc/include/asm/pte-walk.h +++ b/arch/powerpc/include/asm/pte-walk.h @@ -31,6 +31,35 @@ static inline pte_t *find_init_mm_pte(unsigned long ea, unsigned *hshift) pgd_t *pgdir = init_mm.pgd; return __find_linux_pte(pgdir, ea, NULL, hshift); } + +/* + * Convert a kernel vmap virtual address (vmalloc or ioremap space) to a + * physical address, without taking locks. This can be used in real-mode. + */ +static inline phys_addr_t ppc_find_vmap_phys(unsigned long addr) +{ + pte_t *ptep; + phys_addr_t pa; + int hugepage_shift; + + /* + * init_mm does not free page tables, and does not do THP. It may + * have huge pages from huge vmalloc / ioremap etc. + */ + ptep = find_init_mm_pte(addr, &hugepage_shift); + if (WARN_ON(!ptep)) + return 0; + + pa = PFN_PHYS(pte_pfn(*ptep)); + + if (!hugepage_shift) + hugepage_shift = PAGE_SHIFT; + + pa |= addr & ((1ul << hugepage_shift) - 1); + + return pa; +} + /* * This is what we should always use. Any other lockless page table lookup needs * careful audit against THP split. |