Looking its implementation, I'm wondering why this macro and its
sister "pte_offset_map_nested()" are so complex.
I changed their implementations as the following patch shows and my
tiny 32 bits machine still boot fine.
Code size is a little bit decreased:
vmlinux => vmlinux~patched
text: 3045700 3044664 -1036 0%
data: 155756 155756 0 0%
bss: 2269216 2269216 0 0%
total: 5470672 5469636 -1036 0%
Could anybody have a look and tell me if I'm missing something ?
Thanks,
Franck
-- >8 --
diff --git a/include/asm-mips/pgtable-32.h b/include/asm-mips/pgtable-32.h
index 2fbd47e..a0e76e4 100644
--- a/include/asm-mips/pgtable-32.h
+++ b/include/asm-mips/pgtable-32.h
@@ -143,6 +143,7 @@ pfn_pte(unsigned long pfn, pgprot_t prot)
#define __pgd_offset(address) pgd_index(address)
#define __pud_offset(address) (((address) >> PUD_SHIFT) & (PTRS_PER_PUD-1))
#define __pmd_offset(address) (((address) >> PMD_SHIFT) & (PTRS_PER_PMD-1))
+#define __pte_offset(address) (((address) >> PAGE_SHIFT) & (PTRS_PER_PTE-1))
/* to find an entry in a kernel page-table-directory */
#define pgd_offset_k(address) pgd_offset(&init_mm, address)
@@ -153,17 +154,15 @@ pfn_pte(unsigned long pfn, pgprot_t prot)
#define pgd_offset(mm,addr) ((mm)->pgd + pgd_index(addr))
/* Find an entry in the third-level page table.. */
-#define __pte_offset(address) \
- (((address) >> PAGE_SHIFT) & (PTRS_PER_PTE - 1))
#define pte_offset(dir, address) \
((pte_t *) pmd_page_vaddr(*(dir)) + __pte_offset(address))
#define pte_offset_kernel(dir, address)
\
((pte_t *) pmd_page_vaddr(*(dir)) + __pte_offset(address))
#define pte_offset_map(dir, address) \
- ((pte_t *)page_address(pmd_page(*(dir))) + __pte_offset(address))
+ ((pte_t *) pmd_page_vaddr(*(dir)) + __pte_offset(address))
#define pte_offset_map_nested(dir, address) \
- ((pte_t *)page_address(pmd_page(*(dir))) + __pte_offset(address))
+ ((pte_t *) pmd_page_vaddr(*(dir)) + __pte_offset(address))
#define pte_unmap(pte) ((void)(pte))
#define pte_unmap_nested(pte) ((void)(pte))
diff --git a/mm/memory.c b/mm/memory.c
|