3 files changed, 116 insertions, 1 deletions

diff --git a/arch/powerpc/platforms/pseries/mobility.c b/arch/powerpc/platforms/pseries/mobility.c
index 94077fa91959..78f3f74c7056 100644
--- a/arch/powerpc/platforms/pseries/mobility.c
+++ b/arch/powerpc/platforms/pseries/mobility.c
@@ -26,6 +26,7 @@
 #include <asm/machdep.h>
 #include <asm/rtas.h>
 #include "pseries.h"
+#include "vas.h"	/* vas_migration_handler() */
 #include "../../kernel/cacheinfo.h"
 
 static struct kobject *mobility_kobj;
@@ -669,12 +670,16 @@ static int pseries_migrate_partition(u64 handle)
 	if (ret)
 		return ret;
 
+	vas_migration_handler(VAS_SUSPEND);
+
 	ret = pseries_suspend(handle);
 	if (ret == 0)
 		post_mobility_fixup();
 	else
 		pseries_cancel_migration(handle, ret);
 
+	vas_migration_handler(VAS_RESUME);
+
 	return ret;
 }
 
diff --git a/arch/powerpc/platforms/pseries/vas.c b/arch/powerpc/platforms/pseries/vas.c
index fbcf311da0ec..1f59d78c77a1 100644
--- a/arch/powerpc/platforms/pseries/vas.c
+++ b/arch/powerpc/platforms/pseries/vas.c
@@ -30,6 +30,7 @@ static struct hv_vas_cop_feat_caps hv_cop_caps;
 
 static struct vas_caps vascaps[VAS_MAX_FEAT_TYPE];
 static DEFINE_MUTEX(vas_pseries_mutex);
+static bool migration_in_progress;
 
 static long hcall_return_busy_check(long rc)
 {
@@ -356,7 +357,10 @@ static struct vas_window *vas_allocate_window(int vas_id, u64 flags,
 	 * same fault IRQ is not freed by the OS before.
 	 */
 	mutex_lock(&vas_pseries_mutex);
-	rc = allocate_setup_window(txwin, (u64 *)&domain[0],
+	if (migration_in_progress)
+		rc = -EBUSY;
+	else
+		rc = allocate_setup_window(txwin, (u64 *)&domain[0],
 				   cop_feat_caps->win_type);
 	mutex_unlock(&vas_pseries_mutex);
 	if (rc)
@@ -869,6 +873,98 @@ static struct notifier_block pseries_vas_nb = {
 	.notifier_call = pseries_vas_notifier,
 };
 
+/*
+ * For LPM, all windows have to be closed on the source partition
+ * before migration and reopen them on the destination partition
+ * after migration. So closing windows during suspend and
+ * reopen them during resume.
+ */
+int vas_migration_handler(int action)
+{
+	struct vas_cop_feat_caps *caps;
+	int old_nr_creds, new_nr_creds = 0;
+	struct vas_caps *vcaps;
+	int i, rc = 0;
+
+	/*
+	 * NX-GZIP is not enabled. Nothing to do for migration.
+	 */
+	if (!copypaste_feat)
+		return rc;
+
+	mutex_lock(&vas_pseries_mutex);
+
+	if (action == VAS_SUSPEND)
+		migration_in_progress = true;
+	else
+		migration_in_progress = false;
+
+	for (i = 0; i < VAS_MAX_FEAT_TYPE; i++) {
+		vcaps = &vascaps[i];
+		caps = &vcaps->caps;
+		old_nr_creds = atomic_read(&caps->nr_total_credits);
+
+		rc = h_query_vas_capabilities(H_QUERY_VAS_CAPABILITIES,
+					      vcaps->feat,
+					      (u64)virt_to_phys(&hv_cop_caps));
+		if (!rc) {
+			new_nr_creds = be16_to_cpu(hv_cop_caps.target_lpar_creds);
+			/*
+			 * Should not happen. But incase print messages, close
+			 * all windows in the list during suspend and reopen
+			 * windows based on new lpar_creds on the destination
+			 * system.
+			 */
+			if (old_nr_creds != new_nr_creds) {
+				pr_err("Target credits mismatch with the hypervisor\n");
+				pr_err("state(%d): lpar creds: %d HV lpar creds: %d\n",
+					action, old_nr_creds, new_nr_creds);
+				pr_err("Used creds: %d, Active creds: %d\n",
+					atomic_read(&caps->nr_used_credits),
+					vcaps->nr_open_windows - vcaps->nr_close_wins);
+			}
+		} else {
+			pr_err("state(%d): Get VAS capabilities failed with %d\n",
+				action, rc);
+			/*
+			 * We can not stop migration with the current lpm
+			 * implementation. So continue closing all windows in
+			 * the list (during suspend) and return without
+			 * opening windows (during resume) if VAS capabilities
+			 * HCALL failed.
+			 */
+			if (action == VAS_RESUME)
+				goto out;
+		}
+
+		switch (action) {
+		case VAS_SUSPEND:
+			rc = reconfig_close_windows(vcaps, vcaps->nr_open_windows,
+							true);
+			break;
+		case VAS_RESUME:
+			atomic_set(&caps->nr_total_credits, new_nr_creds);
+			rc = reconfig_open_windows(vcaps, new_nr_creds, true);
+			break;
+		default:
+			/* should not happen */
+			pr_err("Invalid migration action %d\n", action);
+			rc = -EINVAL;
+			goto out;
+		}
+
+		/*
+		 * Ignore errors during suspend and return for resume.
+		 */
+		if (rc && (action == VAS_RESUME))
+			goto out;
+	}
+
+out:
+	mutex_unlock(&vas_pseries_mutex);
+	return rc;
+}
+
 static int __init pseries_vas_init(void)
 {
 	struct hv_vas_all_caps *hv_caps;
diff --git a/arch/powerpc/platforms/pseries/vas.h b/arch/powerpc/platforms/pseries/vas.h
index 4ddb1001a0aa..34177881e998 100644
--- a/arch/powerpc/platforms/pseries/vas.h
+++ b/arch/powerpc/platforms/pseries/vas.h
@@ -33,6 +33,11 @@
 #define VAS_GZIP_QOS_CAPABILITIES	0x56516F73477A6970
 #define VAS_GZIP_DEFAULT_CAPABILITIES	0x56446566477A6970
 
+enum vas_migrate_action {
+	VAS_SUSPEND,
+	VAS_RESUME,
+};
+
 /*
  * Co-processor feature - GZIP QoS windows or GZIP default windows
  */
@@ -132,4 +137,13 @@ struct pseries_vas_window {
 int sysfs_add_vas_caps(struct vas_cop_feat_caps *caps);
 int vas_reconfig_capabilties(u8 type);
 int __init sysfs_pseries_vas_init(struct vas_all_caps *vas_caps);
+
+#ifdef CONFIG_PPC_VAS
+int vas_migration_handler(int action);
+#else
+static inline int vas_migration_handler(int action)
+{
+	return 0;
+}
+#endif
 #endif /* _VAS_H */