powerpc/pseries: Utilities to set firmware page state

Newer versions of firmware support page states, which are used by the
collaborative memory manager (future patch) to "loan" pages to the
hypervisor for use by other partitions.

Signed-off-by: Brian King <brking@linux.vnet.ibm.com>
Signed-off-by: Robert Jennings <rcj@linux.vnet.ibm.com>
Acked-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

arch/powerpc/platforms/pseries/plpar_wrappers.h

@@ -42,6 +42,16 @@ static inline long register_slb_shadow(unsigned long cpu, unsigned long vpa)
 	return vpa_call(0x3, cpu, vpa);
 }
 
+static inline long plpar_page_set_loaned(unsigned long vpa)
+{
+	return plpar_hcall_norets(H_PAGE_INIT, H_PAGE_SET_LOANED, vpa, 0);
+}
+
+static inline long plpar_page_set_active(unsigned long vpa)
+{
+	return plpar_hcall_norets(H_PAGE_INIT, H_PAGE_SET_ACTIVE, vpa, 0);
+}
+
 extern void vpa_init(int cpu);
 
 static inline long plpar_pte_enter(unsigned long flags,

include/asm-powerpc/hvcall.h

@@ -92,6 +92,11 @@
 #define H_EXACT			(1UL<<(63-24))	/* Use exact PTE or return H_PTEG_FULL */
 #define H_R_XLATE		(1UL<<(63-25))	/* include a valid logical page num in the pte if the valid bit is set */
 #define H_READ_4		(1UL<<(63-26))	/* Return 4 PTEs */
+#define H_PAGE_STATE_CHANGE	(1UL<<(63-28))
+#define H_PAGE_UNUSED		((1UL<<(63-29)) | (1UL<<(63-30)))
+#define H_PAGE_SET_UNUSED	(H_PAGE_STATE_CHANGE | H_PAGE_UNUSED)
+#define H_PAGE_SET_LOANED	(H_PAGE_SET_UNUSED | (1UL<<(63-31)))
+#define H_PAGE_SET_ACTIVE	H_PAGE_STATE_CHANGE
 #define H_AVPN			(1UL<<(63-32))	/* An avpn is provided as a sanity test */
 #define H_ANDCOND		(1UL<<(63-33))
 #define H_ICACHE_INVALIDATE	(1UL<<(63-40))	/* icbi, etc.  (ignored for IO pages) */