sh: Correct the PTRS_PER_PMD and PMD_SHIFT values
The previous expressions were wrong which made free_pmd_range() explode
when using anything other than 4KB pages (which is why 8KB and 64KB
pages were disabled with the 3-level page table layout).
The problem was that pmd_offset() was returning an index of non-zero
when it should have been returning 0. This non-zero offset was used to
calculate the address of the pmd table to free in free_pmd_range(),
which ended up trying to free an object that was not aligned on a page
boundary.
Now 3-level page tables should work with 4KB, 8KB and 64KB pages.
Signed-off-by: Matt Fleming <matt@console-pimps.org>
diff --git a/arch/sh/include/asm/pgtable_pmd.h b/arch/sh/include/asm/pgtable_pmd.h
index 78dc36e..42a180e 100644
--- a/arch/sh/include/asm/pgtable_pmd.h
+++ b/arch/sh/include/asm/pgtable_pmd.h
@@ -17,11 +17,11 @@
#define USER_PTRS_PER_PGD 2
/* PMD bits */
-#define PMD_SHIFT (PAGE_SHIFT + (PAGE_SHIFT - 3))
+#define PMD_SHIFT (PAGE_SHIFT + (PAGE_SHIFT - PTE_MAGNITUDE))
#define PMD_SIZE (1UL << PMD_SHIFT)
#define PMD_MASK (~(PMD_SIZE-1))
-#define PTRS_PER_PMD (PAGE_SIZE / sizeof(pmd_t))
+#define PTRS_PER_PMD ((1 << PGDIR_SHIFT) / PMD_SIZE)
#define pmd_ERROR(e) \
printk("%s:%d: bad pmd %016llx.\n", __FILE__, __LINE__, pmd_val(e))
diff --git a/arch/sh/mm/Kconfig b/arch/sh/mm/Kconfig
index b3f6c1a..1b43648 100644
--- a/arch/sh/mm/Kconfig
+++ b/arch/sh/mm/Kconfig
@@ -220,7 +220,7 @@
config PAGE_SIZE_8KB
bool "8kB"
- depends on !MMU || X2TLB && !PGTABLE_LEVELS_3
+ depends on !MMU || X2TLB
help
This enables 8kB pages as supported by SH-X2 and later MMUs.
@@ -232,7 +232,7 @@
config PAGE_SIZE_64KB
bool "64kB"
- depends on !MMU || CPU_SH4 && !PGTABLE_LEVELS_3 || CPU_SH5
+ depends on !MMU || CPU_SH4 || CPU_SH5
help
This enables support for 64kB pages, possible on all SH-4
CPUs and later.