powerpc/8xx: Prepare handlers for _PAGE_HUGE for 512k pages.

Prepare ITLB handler to handle _PAGE_HUGE when CONFIG_HUGETLBFS
is enabled. This means that the L1 entry has to be kept in r11
until L2 entry is read, in order to insert _PAGE_HUGE into it.

Also move pgd_offset helpers before pte_update() as they
will be needed there in next patch.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/21fd1de8fba781bededa9474a5a9374aefb1f849.1589866984.git.christophe.leroy@csgroup.eu

diff --git a/arch/powerpc/include/asm/nohash/32/pgtable.h b/arch/powerpc/include/asm/nohash/32/pgtable.h
index ff78bf25f83215b4a0d806caeb192e7fb71cb866..9a287a95acadaf11cbdb5f93f6ae7877a1cd2819 100644 (file)
--- a/arch/powerpc/include/asm/nohash/32/pgtable.h
+++ b/arch/powerpc/include/asm/nohash/32/pgtable.h
@@ -206,6 +206,12 @@ static inline void pmd_clear(pmd_t *pmdp)
 }
 
 
+/* to find an entry in a kernel page-table-directory */
+#define pgd_offset_k(address) pgd_offset(&init_mm, address)
+
+/* to find an entry in a page-table-directory */
+#define pgd_index(address)      ((address) >> PGDIR_SHIFT)
+#define pgd_offset(mm, address)         ((mm)->pgd + pgd_index(address))
 
 /*
  * PTE updates. This function is called whenever an existing
@@ -348,13 +354,6 @@ static inline int pte_young(pte_t pte)
        pfn_to_page((__pa(pmd_val(pmd)) >> PAGE_SHIFT))
 #endif
 
-/* to find an entry in a kernel page-table-directory */
-#define pgd_offset_k(address) pgd_offset(&init_mm, address)
-
-/* to find an entry in a page-table-directory */
-#define pgd_index(address)      ((address) >> PGDIR_SHIFT)
-#define pgd_offset(mm, address)         ((mm)->pgd + pgd_index(address))
-
 /* Find an entry in the third-level page table.. */
 #define pte_index(address)             \
        (((address) >> PAGE_SHIFT) & (PTRS_PER_PTE - 1))

diff --git a/arch/powerpc/kernel/head_8xx.S b/arch/powerpc/kernel/head_8xx.S
index 905205c79a25e30dc696bca0220872717c2a579a..adad8baadcf5760e207acb0d28f7659077849168 100644 (file)
--- a/arch/powerpc/kernel/head_8xx.S
+++ b/arch/powerpc/kernel/head_8xx.S
@@ -196,7 +196,7 @@ SystemCall:
 
 InstructionTLBMiss:
        mtspr   SPRN_SPRG_SCRATCH0, r10
-#if defined(ITLB_MISS_KERNEL) || defined(CONFIG_SWAP)
+#if defined(ITLB_MISS_KERNEL) || defined(CONFIG_SWAP) || defined(CONFIG_HUGETLBFS)
        mtspr   SPRN_SPRG_SCRATCH1, r11
 #endif
 
@@ -235,16 +235,19 @@ InstructionTLBMiss:
        rlwinm  r10, r10, 0, 20, 31
        oris    r10, r10, (swapper_pg_dir - PAGE_OFFSET)@ha
 3:
+       mtcr    r11
 #endif
+#ifdef CONFIG_HUGETLBFS
+       lwz     r11, (swapper_pg_dir-PAGE_OFFSET)@l(r10)        /* Get level 1 entry */
+       mtspr   SPRN_MI_TWC, r11        /* Set segment attributes */
+       mtspr   SPRN_MD_TWC, r11
+#else
        lwz     r10, (swapper_pg_dir-PAGE_OFFSET)@l(r10)        /* Get level 1 entry */
        mtspr   SPRN_MI_TWC, r10        /* Set segment attributes */
-
        mtspr   SPRN_MD_TWC, r10
+#endif
        mfspr   r10, SPRN_MD_TWC
        lwz     r10, 0(r10)     /* Get the pte */
-#ifdef ITLB_MISS_KERNEL
-       mtcr    r11
-#endif
 #ifdef CONFIG_SWAP
        rlwinm  r11, r10, 32-5, _PAGE_PRESENT
        and     r11, r11, r10
@@ -263,7 +266,7 @@ InstructionTLBMiss:
 
        /* Restore registers */
 0:     mfspr   r10, SPRN_SPRG_SCRATCH0
-#if defined(ITLB_MISS_KERNEL) || defined(CONFIG_SWAP)
+#if defined(ITLB_MISS_KERNEL) || defined(CONFIG_SWAP) || defined(CONFIG_HUGETLBFS)
        mfspr   r11, SPRN_SPRG_SCRATCH1
 #endif
        rfi