[PATCH] powerpc: Better pmd_bad() and pud_bad() checks

At present, the powerpc pmd_bad() and pud_bad() macros return false
unless the given pmd or pud is zero.  This patch makes these tests
more thorough, checking if the given pmd or pud looks like a plausible
pte page or pmd page pointer respectively.  This can result in helpful
error messages when messing with the pagetable code.

Signed-off-by: David Gibson <dwg@au1.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This commit is contained in:
David Gibson 2006-03-06 12:51:29 +11:00 коммит произвёл Paul Mackerras
Родитель 23dd640112
Коммит 0f6be7b77c
1 изменённых файлов: 7 добавлений и 2 удалений

Просмотреть файл

@ -188,9 +188,13 @@ static inline pte_t pfn_pte(unsigned long pfn, pgprot_t pgprot)
#define pte_pfn(x) ((unsigned long)((pte_val(x)>>PTE_RPN_SHIFT)))
#define pte_page(x) pfn_to_page(pte_pfn(x))
#define PMD_BAD_BITS (PTE_TABLE_SIZE-1)
#define PUD_BAD_BITS (PMD_TABLE_SIZE-1)
#define pmd_set(pmdp, pmdval) (pmd_val(*(pmdp)) = (pmdval))
#define pmd_none(pmd) (!pmd_val(pmd))
#define pmd_bad(pmd) (pmd_val(pmd) == 0)
#define pmd_bad(pmd) (!is_kernel_addr(pmd_val(pmd)) \
|| (pmd_val(pmd) & PMD_BAD_BITS))
#define pmd_present(pmd) (pmd_val(pmd) != 0)
#define pmd_clear(pmdp) (pmd_val(*(pmdp)) = 0)
#define pmd_page_kernel(pmd) (pmd_val(pmd) & ~PMD_MASKED_BITS)
@ -198,7 +202,8 @@ static inline pte_t pfn_pte(unsigned long pfn, pgprot_t pgprot)
#define pud_set(pudp, pudval) (pud_val(*(pudp)) = (pudval))
#define pud_none(pud) (!pud_val(pud))
#define pud_bad(pud) ((pud_val(pud)) == 0)
#define pud_bad(pud) (!is_kernel_addr(pud_val(pud)) \
|| (pud_val(pud) & PUD_BAD_BITS))
#define pud_present(pud) (pud_val(pud) != 0)
#define pud_clear(pudp) (pud_val(*(pudp)) = 0)
#define pud_page(pud) (pud_val(pud) & ~PUD_MASKED_BITS)