s390/chsc: implement store SCM information

chsc_scm_info will be used to detect all available increments of
storage class memory.

Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

drivers/s390/cio/chsc.c

@@ -52,6 +52,11 @@ int chsc_error_from_response(int response)
 		return -EINVAL;
 	case 0x0004:
 		return -EOPNOTSUPP;
+	case 0x000b:
+		return -EBUSY;
+	case 0x0100:
+	case 0x0102:
+		return -ENOMEM;
 	default:
 		return -EIO;
 	}
@@ -1047,3 +1052,33 @@ out:
 	return rc;
 }
 EXPORT_SYMBOL_GPL(chsc_siosl);
+
+/**
+ * chsc_scm_info() - store SCM information (SSI)
+ * @scm_area: request and response block for SSI
+ * @token: continuation token
+ *
+ * Returns 0 on success.
+ */
+int chsc_scm_info(struct chsc_scm_info *scm_area, u64 token)
+{
+	int ccode, ret;
+
+	memset(scm_area, 0, sizeof(*scm_area));
+	scm_area->request.length = 0x0020;
+	scm_area->request.code = 0x004C;
+	scm_area->reqtok = token;
+
+	ccode = chsc(scm_area);
+	if (ccode > 0) {
+		ret = (ccode == 3) ? -ENODEV : -EBUSY;
+		goto out;
+	}
+	ret = chsc_error_from_response(scm_area->response.code);
+	if (ret != 0)
+		CIO_MSG_EVENT(2, "chsc: scm info failed (rc=%04x)\n",
+			      scm_area->response.code);
+out:
+	return ret;
+}
+EXPORT_SYMBOL_GPL(chsc_scm_info);

drivers/s390/cio/chsc.h

@@ -119,4 +119,39 @@ int chsc_error_from_response(int response);
 
 int chsc_siosl(struct subchannel_id schid);
 
+/* Functions and definitions to query storage-class memory. */
+struct sale {
+	u64 sa;
+	u32 p:4;
+	u32 op_state:4;
+	u32 data_state:4;
+	u32 rank:4;
+	u32 r:1;
+	u32:7;
+	u32 rid:8;
+	u32:32;
+} __packed;
+
+struct chsc_scm_info {
+	struct chsc_header request;
+	u32:32;
+	u64 reqtok;
+	u32 reserved1[4];
+	struct chsc_header response;
+	u64:56;
+	u8 rq;
+	u32 mbc;
+	u64 msa;
+	u16 is;
+	u16 mmc;
+	u32 mci;
+	u64 nr_scm_ini;
+	u64 nr_scm_unini;
+	u32 reserved2[10];
+	u64 restok;
+	struct sale scmal[248];
+} __packed;
+
+int chsc_scm_info(struct chsc_scm_info *scm_area, u64 token);
+
 #endif