Merge branch 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc

* 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc:
  [POWERPC] Bypass hcall stats until cpu features have run
  [POWERPC] Avoid hypervisor statistics calculation in real mode
  [POWERPC] Fix atomicity of TIF update in flush_thread()

5 files changed, 78 insertions, 4 deletions

diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c
index f3d4dd580dd..e53b2988d1b 100644
--- a/arch/powerpc/kernel/process.c
+++ b/arch/powerpc/kernel/process.c
@@ -465,8 +465,13 @@ void flush_thread(void)
 #ifdef CONFIG_PPC64
 	struct thread_info *t = current_thread_info();
 
-	if (t->flags & _TIF_ABI_PENDING)
-		t->flags ^= (_TIF_ABI_PENDING | _TIF_32BIT);
+	if (test_ti_thread_flag(t, TIF_ABI_PENDING)) {
+		clear_ti_thread_flag(t, TIF_ABI_PENDING);
+		if (test_ti_thread_flag(t, TIF_32BIT))
+			clear_ti_thread_flag(t, TIF_32BIT);
+		else
+			set_ti_thread_flag(t, TIF_32BIT);
+	}
 #endif
 
 	discard_lazy_cpu_state();
diff --git a/arch/powerpc/platforms/pseries/hvCall.S b/arch/powerpc/platforms/pseries/hvCall.S
index 5c7e3878989..c1427b3634e 100644
--- a/arch/powerpc/platforms/pseries/hvCall.S
+++ b/arch/powerpc/platforms/pseries/hvCall.S
@@ -30,9 +30,14 @@ END_FTR_SECTION_IFSET(CPU_FTR_PURR);
 	
 /*
  * postcall is performed immediately before function return which
- * allows liberal use of volatile registers.
+ * allows liberal use of volatile registers.  We branch around this
+ * in early init (eg when populating the MMU hashtable) by using an
+ * unconditional cpu feature.
  */
 #define HCALL_INST_POSTCALL					\
+BEGIN_FTR_SECTION;						\
+	b	1f;						\
+END_FTR_SECTION(0, 1);						\
 	ld	r4,STK_PARM(r3)(r1);	/* validate opcode */	\
 	cmpldi	cr7,r4,MAX_HCALL_OPCODE;			\
 	bgt-	cr7,1f;						\
@@ -123,6 +128,40 @@ _GLOBAL(plpar_hcall)
 
 	blr				/* return r3 = status */
 
+/*
+ * plpar_hcall_raw can be called in real mode. kexec/kdump need some
+ * hypervisor calls to be executed in real mode. So plpar_hcall_raw
+ * does not access the per cpu hypervisor call statistics variables,
+ * since these variables may not be present in the RMO region.
+ */
+_GLOBAL(plpar_hcall_raw)
+	HMT_MEDIUM
+
+	mfcr	r0
+	stw	r0,8(r1)
+
+	std     r4,STK_PARM(r4)(r1)     /* Save ret buffer */
+
+	mr	r4,r5
+	mr	r5,r6
+	mr	r6,r7
+	mr	r7,r8
+	mr	r8,r9
+	mr	r9,r10
+
+	HVSC				/* invoke the hypervisor */
+
+	ld	r12,STK_PARM(r4)(r1)
+	std	r4,  0(r12)
+	std	r5,  8(r12)
+	std	r6, 16(r12)
+	std	r7, 24(r12)
+
+	lwz	r0,8(r1)
+	mtcrf	0xff,r0
+
+	blr				/* return r3 = status */
+
 _GLOBAL(plpar_hcall9)
 	HMT_MEDIUM
 
diff --git a/arch/powerpc/platforms/pseries/lpar.c b/arch/powerpc/platforms/pseries/lpar.c
index 7496005566e..843ee964321 100644
--- a/arch/powerpc/platforms/pseries/lpar.c
+++ b/arch/powerpc/platforms/pseries/lpar.c
@@ -378,7 +378,7 @@ static void pSeries_lpar_hptab_clear(void)
 
 	/* TODO: Use bulk call */
 	for (i = 0; i < hpte_count; i++)
-		plpar_pte_remove(0, i, 0, &dummy1, &dummy2);
+		plpar_pte_remove_raw(0, i, 0, &dummy1, &dummy2);
 }
 
 /*
diff --git a/arch/powerpc/platforms/pseries/plpar_wrappers.h b/arch/powerpc/platforms/pseries/plpar_wrappers.h
index 3eb7b294d92..2e4d10c9eea 100644
--- a/arch/powerpc/platforms/pseries/plpar_wrappers.h
+++ b/arch/powerpc/platforms/pseries/plpar_wrappers.h
@@ -78,6 +78,22 @@ static inline long plpar_pte_remove(unsigned long flags, unsigned long ptex,
 	return rc;
 }
 
+/* plpar_pte_remove_raw can be called in real mode. It calls plpar_hcall_raw */
+static inline long plpar_pte_remove_raw(unsigned long flags, unsigned long ptex,
+		unsigned long avpn, unsigned long *old_pteh_ret,
+		unsigned long *old_ptel_ret)
+{
+	long rc;
+	unsigned long retbuf[PLPAR_HCALL_BUFSIZE];
+
+	rc = plpar_hcall_raw(H_REMOVE, retbuf, flags, ptex, avpn);
+
+	*old_pteh_ret = retbuf[0];
+	*old_ptel_ret = retbuf[1];
+
+	return rc;
+}
+
 static inline long plpar_pte_read(unsigned long flags, unsigned long ptex,
 		unsigned long *old_pteh_ret, unsigned long *old_ptel_ret)
 {
diff --git a/include/asm-powerpc/hvcall.h b/include/asm-powerpc/hvcall.h
index 60977806d2f..62efd9d7a43 100644
--- a/include/asm-powerpc/hvcall.h
+++ b/include/asm-powerpc/hvcall.h
@@ -237,6 +237,20 @@ long plpar_hcall_norets(unsigned long opcode, ...);
 long plpar_hcall(unsigned long opcode, unsigned long *retbuf, ...);
 
 /**
+ * plpar_hcall_raw: - Make a hypervisor call without calculating hcall stats
+ * @opcode: The hypervisor call to make.
+ * @retbuf: Buffer to store up to 4 return arguments in.
+ *
+ * This call supports up to 6 arguments and 4 return arguments. Use
+ * PLPAR_HCALL_BUFSIZE to size the return argument buffer.
+ *
+ * Used when phyp interface needs to be called in real mode. Similar to
+ * plpar_hcall, but plpar_hcall_raw works in real mode and does not
+ * calculate hypervisor call statistics.
+ */
+long plpar_hcall_raw(unsigned long opcode, unsigned long *retbuf, ...);
+
+/**
  * plpar_hcall9: - Make a pseries hypervisor call with up to 9 return arguments
  * @opcode: The hypervisor call to make.
  * @retbuf: Buffer to store up to 9 return arguments in.