powerpc/pseries: Add hcall to read 4 ptes at a time in real mode

This adds plpar_pte_read_4_raw() which can be used read 4 PTEs from
PHYP at a time, while in real mode.

It also creates a new hcall9 which can be used in real mode.  It's the
same as plpar_hcall9 but minus the tracing hcall statistics which may
require variables outside the RMO.

Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

1 files changed, 18 insertions, 0 deletions

diff --git a/arch/powerpc/platforms/pseries/plpar_wrappers.h b/arch/powerpc/platforms/pseries/plpar_wrappers.h
index 6c4fd2c3f385..d9801117124b 100644
--- a/arch/powerpc/platforms/pseries/plpar_wrappers.h
+++ b/arch/powerpc/platforms/pseries/plpar_wrappers.h
@@ -191,6 +191,24 @@ static inline long plpar_pte_read_raw(unsigned long flags, unsigned long ptex,
 	return rc;
 }
 
+/*
+ * plpar_pte_read_4_raw can be called in real mode.
+ * ptes must be 8*sizeof(unsigned long)
+ */
+static inline long plpar_pte_read_4_raw(unsigned long flags, unsigned long ptex,
+					unsigned long *ptes)
+
+{
+	long rc;
+	unsigned long retbuf[PLPAR_HCALL9_BUFSIZE];
+
+	rc = plpar_hcall9_raw(H_READ, retbuf, flags | H_READ_4, ptex);
+
+	memcpy(ptes, retbuf, 8*sizeof(unsigned long));
+
+	return rc;
+}
+
 static inline long plpar_pte_protect(unsigned long flags, unsigned long ptex,
 		unsigned long avpn)
 {