X-Git-Url: https://git.karo-electronics.de/?a=blobdiff_plain;ds=sidebyside;f=drivers%2Fs390%2Fblock%2Fdasd_eckd.c;h=bf61274af3bb1a0290f6bfbf897205c079da9b5f;hb=e5fa506173a6ed1ca8d78ba1e390cfdebc2fd49a;hp=50cf96389d2c319c3d67d95a039e00157adc0078;hpb=37542b6a7e73e81f8c066a48e6911e476ee3b22f;p=mv-sheeva.git

diff --git a/drivers/s390/block/dasd_eckd.c b/drivers/s390/block/dasd_eckd.c
index 50cf96389d2..bf61274af3b 100644
--- a/drivers/s390/block/dasd_eckd.c
+++ b/drivers/s390/block/dasd_eckd.c
@@ -2801,6 +2801,73 @@ dasd_eckd_steal_lock(struct dasd_device *device)
 	return rc;
 }
 
+/*
+ * SNID - Sense Path Group ID
+ * This ioctl may be used in situations where I/O is stalled due to
+ * a reserve, so if the normal dasd_smalloc_request fails, we use the
+ * preallocated dasd_reserve_req.
+ */
+static int dasd_eckd_snid(struct dasd_device *device,
+			  void __user *argp)
+{
+	struct dasd_ccw_req *cqr;
+	int rc;
+	struct ccw1 *ccw;
+	int useglobal;
+	struct dasd_snid_ioctl_data usrparm;
+
+	if (!capable(CAP_SYS_ADMIN))
+		return -EACCES;
+
+	if (copy_from_user(&usrparm, argp, sizeof(usrparm)))
+		return -EFAULT;
+
+	useglobal = 0;
+	cqr = dasd_smalloc_request(DASD_ECKD_MAGIC, 1,
+				   sizeof(struct dasd_snid_data), device);
+	if (IS_ERR(cqr)) {
+		mutex_lock(&dasd_reserve_mutex);
+		useglobal = 1;
+		cqr = &dasd_reserve_req->cqr;
+		memset(cqr, 0, sizeof(*cqr));
+		memset(&dasd_reserve_req->ccw, 0,
+		       sizeof(dasd_reserve_req->ccw));
+		cqr->cpaddr = &dasd_reserve_req->ccw;
+		cqr->data = &dasd_reserve_req->data;
+		cqr->magic = DASD_ECKD_MAGIC;
+	}
+	ccw = cqr->cpaddr;
+	ccw->cmd_code = DASD_ECKD_CCW_SNID;
+	ccw->flags |= CCW_FLAG_SLI;
+	ccw->count = 12;
+	ccw->cda = (__u32)(addr_t) cqr->data;
+	cqr->startdev = device;
+	cqr->memdev = device;
+	clear_bit(DASD_CQR_FLAGS_USE_ERP, &cqr->flags);
+	set_bit(DASD_CQR_FLAGS_FAILFAST, &cqr->flags);
+	cqr->retries = 5;
+	cqr->expires = 10 * HZ;
+	cqr->buildclk = get_clock();
+	cqr->status = DASD_CQR_FILLED;
+	cqr->lpm = usrparm.path_mask;
+
+	rc = dasd_sleep_on_immediatly(cqr);
+	/* verify that I/O processing didn't modify the path mask */
+	if (!rc && usrparm.path_mask && (cqr->lpm != usrparm.path_mask))
+		rc = -EIO;
+	if (!rc) {
+		usrparm.data = *((struct dasd_snid_data *)cqr->data);
+		if (copy_to_user(argp, &usrparm, sizeof(usrparm)))
+			rc = -EFAULT;
+	}
+
+	if (useglobal)
+		mutex_unlock(&dasd_reserve_mutex);
+	else
+		dasd_sfree_request(cqr, cqr->memdev);
+	return rc;
+}
+
 /*
  * Read performance statistics
  */
@@ -3036,6 +3103,8 @@ dasd_eckd_ioctl(struct dasd_block *block, unsigned int cmd, void __user *argp)
 		return dasd_eckd_reserve(device);
 	case BIODASDSLCK:
 		return dasd_eckd_steal_lock(device);
+	case BIODASDSNID:
+		return dasd_eckd_snid(device, argp);
 	case BIODASDSYMMIO:
 		return dasd_symm_io(device, argp);
 	default: