powerpc/32s: Cleanup around PTE_FLAGS_OFFSET in hash_low.S

PTE_FLAGS_OFFSET is defined in asm/page_32.h and used only
in hash_low.S

And PTE_FLAGS_OFFSET nullity depends on CONFIG_PTE_64BIT

Instead of tests like #if (PTE_FLAGS_OFFSET != 0), use
CONFIG_PTE_64BIT related code.

Also move the definition of PTE_FLAGS_OFFSET into hash_low.S
directly, that improves readability.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/f5bc21db7a33dab55924734e6060c2e9daed562e.1606247495.git.christophe.leroy@csgroup.eu

diff --git a/arch/powerpc/include/asm/page_32.h b/arch/powerpc/include/asm/page_32.h
index d64dfe3ac712469b183a4430e5fb2e15843c957a..56f21760632749dae8f94b74289d02f138501036 100644 (file)
--- a/arch/powerpc/include/asm/page_32.h
+++ b/arch/powerpc/include/asm/page_32.h
@@ -16,12 +16,6 @@
 #define ARCH_DMA_MINALIGN      L1_CACHE_BYTES
 #endif
 
-#ifdef CONFIG_PTE_64BIT
-#define PTE_FLAGS_OFFSET       4       /* offset of PTE flags, in bytes */
-#else
-#define PTE_FLAGS_OFFSET       0
-#endif
-
 #if defined(CONFIG_PPC_256K_PAGES) || \
     (defined(CONFIG_PPC_8xx) && defined(CONFIG_PPC_16K_PAGES))
 #define PTE_SHIFT      (PAGE_SHIFT - PTE_T_LOG2 - 2)   /* 1/4 of a page */

diff --git a/arch/powerpc/mm/book3s32/hash_low.S b/arch/powerpc/mm/book3s32/hash_low.S
index b0bb9d19340084541753ff05204b92d28a69b717..0e6dc830c38bf6cb1b78e41e04502356254299c8 100644 (file)
--- a/arch/powerpc/mm/book3s32/hash_low.S
+++ b/arch/powerpc/mm/book3s32/hash_low.S
@@ -26,6 +26,12 @@
 #include <asm/feature-fixups.h>
 #include <asm/code-patching-asm.h>
 
+#ifdef CONFIG_PTE_64BIT
+#define PTE_FLAGS_OFFSET       4       /* offset of PTE flags, in bytes */
+#else
+#define PTE_FLAGS_OFFSET       0
+#endif
+
 /*
  * Load a PTE into the hash table, if possible.
  * The address is in r4, and r3 contains an access flag:
@@ -88,6 +94,11 @@ _GLOBAL(hash_page)
        rlwimi  r8,r4,22,20,29          /* insert next 10 bits of address */
 #else
        rlwimi  r8,r4,23,20,28          /* compute pte address */
+       /*
+        * If PTE_64BIT is set, the low word is the flags word; use that
+        * word for locking since it contains all the interesting bits.
+        */
+       addi    r8,r8,PTE_FLAGS_OFFSET
 #endif
 
        /*
@@ -95,13 +106,7 @@ _GLOBAL(hash_page)
         * because almost always, there won't be a permission violation
         * and there won't already be an HPTE, and thus we will have
         * to update the PTE to set _PAGE_HASHPTE.  -- paulus.
-        *
-        * If PTE_64BIT is set, the low word is the flags word; use that
-        * word for locking since it contains all the interesting bits.
         */
-#if (PTE_FLAGS_OFFSET != 0)
-       addi    r8,r8,PTE_FLAGS_OFFSET
-#endif
 .Lretry:
        lwarx   r6,0,r8                 /* get linux-style pte, flag word */
 #ifdef CONFIG_PPC_KUAP
@@ -489,8 +494,9 @@ _GLOBAL(flush_hash_pages)
        rlwimi  r5,r4,22,20,29
 #else
        rlwimi  r5,r4,23,20,28
+       addi    r5,r5,PTE_FLAGS_OFFSET
 #endif
-1:     lwz     r0,PTE_FLAGS_OFFSET(r5)
+1:     lwz     r0,0(r5)
        cmpwi   cr1,r6,1
        andi.   r0,r0,_PAGE_HASHPTE
        bne     2f
@@ -534,9 +540,6 @@ _GLOBAL(flush_hash_pages)
         * already clear, we're done (for this pte).  If not,
         * clear it (atomically) and proceed.  -- paulus.
         */
-#if (PTE_FLAGS_OFFSET != 0)
-       addi    r5,r5,PTE_FLAGS_OFFSET
-#endif
 33:    lwarx   r8,0,r5                 /* fetch the pte flags word */
        andi.   r0,r8,_PAGE_HASHPTE
        beq     8f                      /* done if HASHPTE is already clear */