[S390] dasd: use idal for device characteristics

If the rdc_buffer is above 2G we need indirect addresssing so we have
to use an idaw to give the rdc_buffer to the ccw.
If the rdc_buffer is under 2G nothing changes.

Signed-off-by: Stefan Haberland <stefan.haberland@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

1 files changed, 11 insertions, 2 deletions

diff --git a/drivers/s390/block/dasd.c b/drivers/s390/block/dasd.c
index 53b8c255360a..aaccc8ecfa8f 100644
--- a/drivers/s390/block/dasd.c
+++ b/drivers/s390/block/dasd.c
@@ -2533,6 +2533,7 @@ static struct dasd_ccw_req *dasd_generic_build_rdc(struct dasd_device *device,
 {
         struct dasd_ccw_req *cqr;
         struct ccw1 *ccw;
+        unsigned long *idaw;
 
         cqr = dasd_smalloc_request(magic, 1 /* RDC */, rdc_buffer_size, device);
 
@@ -2546,9 +2547,17 @@ static struct dasd_ccw_req *dasd_generic_build_rdc(struct dasd_device *device,
 
         ccw = cqr->cpaddr;
         ccw->cmd_code = CCW_CMD_RDC;
-        ccw->cda = (__u32)(addr_t)rdc_buffer;
-        ccw->count = rdc_buffer_size;
+        if (idal_is_needed(rdc_buffer, rdc_buffer_size)) {
+                idaw = (unsigned long *) (cqr->data);
+                ccw->cda = (__u32)(addr_t) idaw;
+                ccw->flags = CCW_FLAG_IDA;
+                idaw = idal_create_words(idaw, rdc_buffer, rdc_buffer_size);
+        } else {
+                ccw->cda = (__u32)(addr_t) rdc_buffer;
+                ccw->flags = 0;
+        }
 
+        ccw->count = rdc_buffer_size;
         cqr->startdev = device;
         cqr->memdev = device;
         cqr->expires = 10*HZ;