powerpc/mm: Add helper for converting pte bit to hpte bits

Instead of open coding it in multiple code paths, export the helper
and add more documentation. Also make sure we don't make assumption
regarding pte bit position

Acked-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

diff --git a/arch/powerpc/include/asm/book3s/64/hash.h b/arch/powerpc/include/asm/book3s/64/hash.h
index e4ea9d73a541946a81bc714751d3e71ebf25e616..9c212449b2e822036aee1a895289c5c47675e198 100644 (file)
--- a/arch/powerpc/include/asm/book3s/64/hash.h
+++ b/arch/powerpc/include/asm/book3s/64/hash.h
@@ -236,6 +236,7 @@ extern unsigned long pmd_hugepage_update(struct mm_struct *mm,
                                         pmd_t *pmdp,
                                         unsigned long clr,
                                         unsigned long set);
+extern unsigned long htab_convert_pte_flags(unsigned long pteflags);
 /* Atomic PTE updates */
 static inline unsigned long pte_update(struct mm_struct *mm,
                                       unsigned long addr,

diff --git a/arch/powerpc/mm/hash64_4k.c b/arch/powerpc/mm/hash64_4k.c
index 3b49c6f187410b7e2908129f37272b32412fe5ca..ee863137035aebd78358933499078ef1bb25c9a7 100644 (file)
--- a/arch/powerpc/mm/hash64_4k.c
+++ b/arch/powerpc/mm/hash64_4k.c
@@ -53,18 +53,7 @@ int __hash_page_4K(unsigned long ea, unsigned long access, unsigned long vsid,
         * PP bits. _PAGE_USER is already PP bit 0x2, so we only
         * need to add in 0x1 if it's a read-only user page
         */
-       rflags = new_pte & _PAGE_USER;
-       if ((new_pte & _PAGE_USER) && !((new_pte & _PAGE_RW) &&
-                                       (new_pte & _PAGE_DIRTY)))
-               rflags |= 0x1;
-       /*
-        * _PAGE_EXEC -> HW_NO_EXEC since it's inverted
-        */
-       rflags |= ((new_pte & _PAGE_EXEC) ? 0 : HPTE_R_N);
-       /*
-        * Always add C and Memory coherence bit
-        */
-       rflags |= HPTE_R_C | HPTE_R_M;
+       rflags = htab_convert_pte_flags(new_pte);
        /*
         * Add in WIMG bits
         */

diff --git a/arch/powerpc/mm/hash64_64k.c b/arch/powerpc/mm/hash64_64k.c
index fc0898eb309d8601759eda376a23d6786e1a417b..b14280e9d850a60ac7800811e9fe59765d061de5 100644 (file)
--- a/arch/powerpc/mm/hash64_64k.c
+++ b/arch/powerpc/mm/hash64_64k.c
@@ -85,22 +85,7 @@ int __hash_page_4K(unsigned long ea, unsigned long access, unsigned long vsid,
         * Handle the subpage protection bits
         */
        subpg_pte = new_pte & ~subpg_prot;
-       /*
-        * PP bits. _PAGE_USER is already PP bit 0x2, so we only
-        * need to add in 0x1 if it's a read-only user page
-        */
-       rflags = subpg_pte & _PAGE_USER;
-       if ((subpg_pte & _PAGE_USER) && !((subpg_pte & _PAGE_RW) &&
-                                       (subpg_pte & _PAGE_DIRTY)))
-               rflags |= 0x1;
-       /*
-        * _PAGE_EXEC -> HW_NO_EXEC since it's inverted
-        */
-       rflags |= ((subpg_pte & _PAGE_EXEC) ? 0 : HPTE_R_N);
-       /*
-        * Always add C and Memory coherence bit
-        */
-       rflags |= HPTE_R_C | HPTE_R_M;
+       rflags = htab_convert_pte_flags(subpg_pte);
        /*
         * Add in WIMG bits
         */
@@ -271,22 +256,8 @@ int __hash_page_64K(unsigned long ea, unsigned long access,
                        new_pte |= _PAGE_DIRTY;
        } while (old_pte != __cmpxchg_u64((unsigned long *)ptep,
                                          old_pte, new_pte));
-       /*
-        * PP bits. _PAGE_USER is already PP bit 0x2, so we only
-        * need to add in 0x1 if it's a read-only user page
-        */
-       rflags = new_pte & _PAGE_USER;
-       if ((new_pte & _PAGE_USER) && !((new_pte & _PAGE_RW) &&
-                                       (new_pte & _PAGE_DIRTY)))
-               rflags |= 0x1;
-       /*
-        * _PAGE_EXEC -> HW_NO_EXEC since it's inverted
-        */
-       rflags |= ((new_pte & _PAGE_EXEC) ? 0 : HPTE_R_N);
-       /*
-        * Always add C and Memory coherence bit
-        */
-       rflags |= HPTE_R_C | HPTE_R_M;
+
+       rflags = htab_convert_pte_flags(new_pte);
        /*
         * Add in WIMG bits
         */

diff --git a/arch/powerpc/mm/hash_utils_64.c b/arch/powerpc/mm/hash_utils_64.c
index cab2deb8d20b2b077ec9efb57b868c2a6566465c..6c67bd0bec55743ba99c67381934fde6960c8da1 100644 (file)
--- a/arch/powerpc/mm/hash_utils_64.c
+++ b/arch/powerpc/mm/hash_utils_64.c
@@ -159,20 +159,26 @@ static struct mmu_psize_def mmu_psize_defaults_gp[] = {
        },
 };
 
-static unsigned long htab_convert_pte_flags(unsigned long pteflags)
+unsigned long htab_convert_pte_flags(unsigned long pteflags)
 {
-       unsigned long rflags = pteflags & 0x1fa;
+       unsigned long rflags = 0;
 
        /* _PAGE_EXEC -> NOEXEC */
        if ((pteflags & _PAGE_EXEC) == 0)
                rflags |= HPTE_R_N;
-
-       /* PP bits. PAGE_USER is already PP bit 0x2, so we only
-        * need to add in 0x1 if it's a read-only user page
+       /*
+        * PP bits:
+        * Linux use slb key 0 for kernel and 1 for user.
+        * kernel areas are mapped by PP bits 00
+        * and and there is no kernel RO (_PAGE_KERNEL_RO).
+        * User area mapped by 0x2 and read only use by
+        * 0x3.
         */
-       if ((pteflags & _PAGE_USER) && !((pteflags & _PAGE_RW) &&
-                                        (pteflags & _PAGE_DIRTY)))
-               rflags |= 1;
+       if (pteflags & _PAGE_USER) {
+               rflags |= 0x2;
+               if (!((pteflags & _PAGE_RW) && (pteflags & _PAGE_DIRTY)))
+                       rflags |= 0x1;
+       }
        /*
         * Always add "C" bit for perf. Memory coherence is always enabled
         */

diff --git a/arch/powerpc/mm/hugepage-hash64.c b/arch/powerpc/mm/hugepage-hash64.c
index 4d87122cf6a725805d3de6bdf46cc44b9d3f91ef..91fcac6f989d69f0e64fa3a180b6252f9b4e4fb0 100644 (file)
--- a/arch/powerpc/mm/hugepage-hash64.c
+++ b/arch/powerpc/mm/hugepage-hash64.c
@@ -54,18 +54,7 @@ int __hash_page_thp(unsigned long ea, unsigned long access, unsigned long vsid,
                        new_pmd |= _PAGE_DIRTY;
        } while (old_pmd != __cmpxchg_u64((unsigned long *)pmdp,
                                          old_pmd, new_pmd));
-       /*
-        * PP bits. _PAGE_USER is already PP bit 0x2, so we only
-        * need to add in 0x1 if it's a read-only user page
-        */
-       rflags = new_pmd & _PAGE_USER;
-       if ((new_pmd & _PAGE_USER) && !((new_pmd & _PAGE_RW) &&
-                                          (new_pmd & _PAGE_DIRTY)))
-               rflags |= 0x1;
-       /*
-        * _PAGE_EXEC -> HW_NO_EXEC since it's inverted
-        */
-       rflags |= ((new_pmd & _PAGE_EXEC) ? 0 : HPTE_R_N);
+       rflags = htab_convert_pte_flags(new_pmd);
 
 #if 0
        if (!cpu_has_feature(CPU_FTR_COHERENT_ICACHE)) {

diff --git a/arch/powerpc/mm/hugetlbpage-hash64.c b/arch/powerpc/mm/hugetlbpage-hash64.c
index 7584e8445512739a6bdd03698fff71f0feff61e3..304c8520506e72be36563a00501c9630828cef88 100644 (file)
--- a/arch/powerpc/mm/hugetlbpage-hash64.c
+++ b/arch/powerpc/mm/hugetlbpage-hash64.c
@@ -59,10 +59,8 @@ int __hash_page_huge(unsigned long ea, unsigned long access, unsigned long vsid,
                        new_pte |= _PAGE_DIRTY;
        } while(old_pte != __cmpxchg_u64((unsigned long *)ptep,
                                         old_pte, new_pte));
+       rflags = htab_convert_pte_flags(new_pte);
 
-       rflags = 0x2 | (!(new_pte & _PAGE_RW));
-       /* _PAGE_EXEC -> HW_NO_EXEC since it's inverted */
-       rflags |= ((new_pte & _PAGE_EXEC) ? 0 : HPTE_R_N);
        sz = ((1UL) << shift);
        if (!cpu_has_feature(CPU_FTR_COHERENT_ICACHE))
                /* No CPU has hugepages but lacks no execute, so we