[POWERPC] Use PAGE_OFFSET to tell if an address is user/kernel in SW TLB handlers

Move to using PAGE_OFFSET instead of TASK_SIZE or KERNELBASE value on
6xx/40x/44x/fsl-booke to determine if the faulting address is a kernel or
user space address.  This mimics how the macro is_kernel_addr() works.

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
diff --git a/arch/powerpc/kernel/head_32.S b/arch/powerpc/kernel/head_32.S
index d83f04e..a5b13ae 100644
--- a/arch/powerpc/kernel/head_32.S
+++ b/arch/powerpc/kernel/head_32.S
@@ -469,12 +469,12 @@
 	mfctr	r0
 	/* Get PTE (linux-style) and check access */
 	mfspr	r3,SPRN_IMISS
-	lis	r1,KERNELBASE@h		/* check if kernel address */
-	cmplw	0,r3,r1
+	lis	r1,PAGE_OFFSET@h		/* check if kernel address */
+	cmplw	0,r1,r3
 	mfspr	r2,SPRN_SPRG3
 	li	r1,_PAGE_USER|_PAGE_PRESENT /* low addresses tested as user */
 	lwz	r2,PGDIR(r2)
-	blt+	112f
+	bge-	112f
 	mfspr	r2,SPRN_SRR1		/* and MSR_PR bit from SRR1 */
 	rlwimi	r1,r2,32-12,29,29	/* shift MSR_PR to _PAGE_USER posn */
 	lis	r2,swapper_pg_dir@ha	/* if kernel address, use */
@@ -543,12 +543,12 @@
 	mfctr	r0
 	/* Get PTE (linux-style) and check access */
 	mfspr	r3,SPRN_DMISS
-	lis	r1,KERNELBASE@h		/* check if kernel address */
-	cmplw	0,r3,r1
+	lis	r1,PAGE_OFFSET@h		/* check if kernel address */
+	cmplw	0,r1,r3
 	mfspr	r2,SPRN_SPRG3
 	li	r1,_PAGE_USER|_PAGE_PRESENT /* low addresses tested as user */
 	lwz	r2,PGDIR(r2)
-	blt+	112f
+	bge-	112f
 	mfspr	r2,SPRN_SRR1		/* and MSR_PR bit from SRR1 */
 	rlwimi	r1,r2,32-12,29,29	/* shift MSR_PR to _PAGE_USER posn */
 	lis	r2,swapper_pg_dir@ha	/* if kernel address, use */
@@ -615,12 +615,12 @@
 	mfctr	r0
 	/* Get PTE (linux-style) and check access */
 	mfspr	r3,SPRN_DMISS
-	lis	r1,KERNELBASE@h		/* check if kernel address */
-	cmplw	0,r3,r1
+	lis	r1,PAGE_OFFSET@h		/* check if kernel address */
+	cmplw	0,r1,r3
 	mfspr	r2,SPRN_SPRG3
 	li	r1,_PAGE_RW|_PAGE_USER|_PAGE_PRESENT /* access flags */
 	lwz	r2,PGDIR(r2)
-	blt+	112f
+	bge-	112f
 	mfspr	r2,SPRN_SRR1		/* and MSR_PR bit from SRR1 */
 	rlwimi	r1,r2,32-12,29,29	/* shift MSR_PR to _PAGE_USER posn */
 	lis	r2,swapper_pg_dir@ha	/* if kernel address, use */