s390/dasd: Recognise data for ESE volumes

In order to work with Extent Space Efficient (ESE) volumes, certain
viable information about those volumes and the corresponding extent
pool (such as extent size, configured space, allocated space, etc.) can
be provided.

Use the CCW commands Volume Storage Query and Logical Configuration
Query to receive detailed information about ESE volumes and the extent
pool respectively. These information are made accessible via internal
functions for subsequent users, and via sysfs attributes for userpsace
usage.

The new sysfs attributes reside in separate directories called capacity
and extent_pool.

attributes:
ese:
    0/1 depending on whether the volume is an ESE volume

Capacity related attributes:
space_allocated:
    Space currently allocated by the volume (in cyl)
space_configured:
    Remaining space in the extent pool (in cyl)
logical_capacity:
    The entire addressable space for this volume (in cyl)

Extent Pool related attributes:
pool_id:
    ID of the extent pool the volume in question resides in
pool_oos:
    Extent pool is out-of-space
extent_size:
    Size of a single extent in this pool
cap_at_warnlevel
    Extent pool capacity at warn level
warn_threshold:
    Threshold at which percentage of remaining extent pool space a
    warning message is issued

Signed-off-by: Jan Höppner <hoeppner@linux.ibm.com>
Reviewed-by: Stefan Haberland <sth@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>

1 files changed, 276 insertions, 0 deletions

diff --git a/drivers/s390/block/dasd_eckd.c b/drivers/s390/block/dasd_eckd.c
index 9e81f766d938..67156d46c236 100644
--- a/drivers/s390/block/dasd_eckd.c
+++ b/drivers/s390/block/dasd_eckd.c
@@ -108,6 +108,7 @@ struct check_attention_work_data {
 	__u8 lpum;
 };
 
+static int dasd_eckd_ext_pool_id(struct dasd_device *);
 static int prepare_itcw(struct itcw *, unsigned int, unsigned int, int,
 			struct dasd_device *, struct dasd_device *,
 			unsigned int, int, unsigned int, unsigned int,
@@ -1470,6 +1471,252 @@ static int dasd_eckd_read_features(struct dasd_device *device)
 	return rc;
 }
 
+/* Read Volume Information - Volume Storage Query */
+static int dasd_eckd_read_vol_info(struct dasd_device *device)
+{
+	struct dasd_eckd_private *private = device->private;
+	struct dasd_psf_prssd_data *prssdp;
+	struct dasd_rssd_vsq *vsq;
+	struct dasd_ccw_req *cqr;
+	struct ccw1 *ccw;
+	int rc;
+
+	/* This command cannot be executed on an alias device */
+	if (private->uid.type == UA_BASE_PAV_ALIAS ||
+	    private->uid.type == UA_HYPER_PAV_ALIAS)
+		return 0;
+
+	cqr = dasd_smalloc_request(DASD_ECKD_MAGIC, 2 /* PSF + RSSD */,
+				   sizeof(*prssdp) + sizeof(*vsq), device, NULL);
+	if (IS_ERR(cqr)) {
+		DBF_EVENT_DEVID(DBF_WARNING, device->cdev, "%s",
+				"Could not allocate initialization request");
+		return PTR_ERR(cqr);
+	}
+
+	/* Prepare for Read Subsystem Data */
+	prssdp = cqr->data;
+	prssdp->order = PSF_ORDER_PRSSD;
+	prssdp->suborder = PSF_SUBORDER_VSQ;	/* Volume Storage Query */
+	prssdp->lss = private->ned->ID;
+	prssdp->volume = private->ned->unit_addr;
+
+	ccw = cqr->cpaddr;
+	ccw->cmd_code = DASD_ECKD_CCW_PSF;
+	ccw->count = sizeof(*prssdp);
+	ccw->flags |= CCW_FLAG_CC;
+	ccw->cda = (__u32)(addr_t)prssdp;
+
+	/* Read Subsystem Data - Volume Storage Query */
+	vsq = (struct dasd_rssd_vsq *)(prssdp + 1);
+	memset(vsq, 0, sizeof(*vsq));
+
+	ccw++;
+	ccw->cmd_code = DASD_ECKD_CCW_RSSD;
+	ccw->count = sizeof(*vsq);
+	ccw->flags |= CCW_FLAG_SLI;
+	ccw->cda = (__u32)(addr_t)vsq;
+
+	cqr->buildclk = get_tod_clock();
+	cqr->status = DASD_CQR_FILLED;
+	cqr->startdev = device;
+	cqr->memdev = device;
+	cqr->block = NULL;
+	cqr->retries = 256;
+	cqr->expires = device->default_expires * HZ;
+	/* The command might not be supported. Suppress the error output */
+	__set_bit(DASD_CQR_SUPPRESS_CR, &cqr->flags);
+
+	rc = dasd_sleep_on_interruptible(cqr);
+	if (rc == 0) {
+		memcpy(&private->vsq, vsq, sizeof(*vsq));
+	} else {
+		dev_warn(&device->cdev->dev,
+			 "Reading the volume storage information failed with rc=%d\n", rc);
+	}
+
+	dasd_sfree_request(cqr, cqr->memdev);
+
+	return rc;
+}
+
+static int dasd_eckd_is_ese(struct dasd_device *device)
+{
+	struct dasd_eckd_private *private = device->private;
+
+	return private->vsq.vol_info.ese;
+}
+
+static int dasd_eckd_ext_pool_id(struct dasd_device *device)
+{
+	struct dasd_eckd_private *private = device->private;
+
+	return private->vsq.extent_pool_id;
+}
+
+/*
+ * This value represents the total amount of available space. As more space is
+ * allocated by ESE volumes, this value will decrease.
+ * The data for this value is therefore updated on any call.
+ */
+static int dasd_eckd_space_configured(struct dasd_device *device)
+{
+	struct dasd_eckd_private *private = device->private;
+	int rc;
+
+	rc = dasd_eckd_read_vol_info(device);
+
+	return rc ? : private->vsq.space_configured;
+}
+
+/*
+ * The value of space allocated by an ESE volume may have changed and is
+ * therefore updated on any call.
+ */
+static int dasd_eckd_space_allocated(struct dasd_device *device)
+{
+	struct dasd_eckd_private *private = device->private;
+	int rc;
+
+	rc = dasd_eckd_read_vol_info(device);
+
+	return rc ? : private->vsq.space_allocated;
+}
+
+static int dasd_eckd_logical_capacity(struct dasd_device *device)
+{
+	struct dasd_eckd_private *private = device->private;
+
+	return private->vsq.logical_capacity;
+}
+
+static void dasd_eckd_cpy_ext_pool_data(struct dasd_device *device,
+					struct dasd_rssd_lcq *lcq)
+{
+	struct dasd_eckd_private *private = device->private;
+	int pool_id = dasd_eckd_ext_pool_id(device);
+	struct dasd_ext_pool_sum eps;
+	int i;
+
+	for (i = 0; i < lcq->pool_count; i++) {
+		eps = lcq->ext_pool_sum[i];
+		if (eps.pool_id == pool_id) {
+			memcpy(&private->eps, &eps,
+			       sizeof(struct dasd_ext_pool_sum));
+		}
+	}
+}
+
+/* Read Extent Pool Information - Logical Configuration Query */
+static int dasd_eckd_read_ext_pool_info(struct dasd_device *device)
+{
+	struct dasd_eckd_private *private = device->private;
+	struct dasd_psf_prssd_data *prssdp;
+	struct dasd_rssd_lcq *lcq;
+	struct dasd_ccw_req *cqr;
+	struct ccw1 *ccw;
+	int rc;
+
+	/* This command cannot be executed on an alias device */
+	if (private->uid.type == UA_BASE_PAV_ALIAS ||
+	    private->uid.type == UA_HYPER_PAV_ALIAS)
+		return 0;
+
+	cqr = dasd_smalloc_request(DASD_ECKD_MAGIC, 2 /* PSF + RSSD */,
+				   sizeof(*prssdp) + sizeof(*lcq), device, NULL);
+	if (IS_ERR(cqr)) {
+		DBF_EVENT_DEVID(DBF_WARNING, device->cdev, "%s",
+				"Could not allocate initialization request");
+		return PTR_ERR(cqr);
+	}
+
+	/* Prepare for Read Subsystem Data */
+	prssdp = cqr->data;
+	memset(prssdp, 0, sizeof(*prssdp));
+	prssdp->order = PSF_ORDER_PRSSD;
+	prssdp->suborder = PSF_SUBORDER_LCQ;	/* Logical Configuration Query */
+
+	ccw = cqr->cpaddr;
+	ccw->cmd_code = DASD_ECKD_CCW_PSF;
+	ccw->count = sizeof(*prssdp);
+	ccw->flags |= CCW_FLAG_CC;
+	ccw->cda = (__u32)(addr_t)prssdp;
+
+	lcq = (struct dasd_rssd_lcq *)(prssdp + 1);
+	memset(lcq, 0, sizeof(*lcq));
+
+	ccw++;
+	ccw->cmd_code = DASD_ECKD_CCW_RSSD;
+	ccw->count = sizeof(*lcq);
+	ccw->flags |= CCW_FLAG_SLI;
+	ccw->cda = (__u32)(addr_t)lcq;
+
+	cqr->buildclk = get_tod_clock();
+	cqr->status = DASD_CQR_FILLED;
+	cqr->startdev = device;
+	cqr->memdev = device;
+	cqr->block = NULL;
+	cqr->retries = 256;
+	cqr->expires = device->default_expires * HZ;
+	/* The command might not be supported. Suppress the error output */
+	__set_bit(DASD_CQR_SUPPRESS_CR, &cqr->flags);
+
+	rc = dasd_sleep_on_interruptible(cqr);
+	if (rc == 0) {
+		dasd_eckd_cpy_ext_pool_data(device, lcq);
+	} else {
+		dev_warn(&device->cdev->dev,
+			 "Reading the logical configuration failed with rc=%d\n", rc);
+	}
+
+	dasd_sfree_request(cqr, cqr->memdev);
+
+	return rc;
+}
+
+/*
+ * Depending on the device type, the extent size is specified either as
+ * cylinders per extent (CKD) or size per extent (FBA)
+ * A 1GB size corresponds to 1113cyl, and 16MB to 21cyl.
+ */
+static int dasd_eckd_ext_size(struct dasd_device *device)
+{
+	struct dasd_eckd_private *private = device->private;
+	struct dasd_ext_pool_sum eps = private->eps;
+
+	if (!eps.flags.extent_size_valid)
+		return 0;
+	if (eps.extent_size.size_1G)
+		return 1113;
+	if (eps.extent_size.size_16M)
+		return 21;
+
+	return 0;
+}
+
+static int dasd_eckd_ext_pool_warn_thrshld(struct dasd_device *device)
+{
+	struct dasd_eckd_private *private = device->private;
+
+	return private->eps.warn_thrshld;
+}
+
+static int dasd_eckd_ext_pool_cap_at_warnlevel(struct dasd_device *device)
+{
+	struct dasd_eckd_private *private = device->private;
+
+	return private->eps.flags.capacity_at_warnlevel;
+}
+
+/*
+ * Extent Pool out of space
+ */
+static int dasd_eckd_ext_pool_oos(struct dasd_device *device)
+{
+	struct dasd_eckd_private *private = device->private;
+
+	return private->eps.flags.pool_oos;
+}
 
 /*
  * Build CP for Perform Subsystem Function - SSC.
@@ -1700,6 +1947,16 @@ dasd_eckd_check_characteristics(struct dasd_device *device)
 	/* Read Feature Codes */
 	dasd_eckd_read_features(device);
 
+	/* Read Volume Information */
+	rc = dasd_eckd_read_vol_info(device);
+	if (rc)
+		goto out_err3;
+
+	/* Read Extent Pool Information */
+	rc = dasd_eckd_read_ext_pool_info(device);
+	if (rc)
+		goto out_err3;
+
 	/* Read Device Characteristics */
 	rc = dasd_generic_read_dev_chars(device, DASD_ECKD_MAGIC,
 					 &private->rdc_data, 64);
@@ -4944,6 +5201,16 @@ static int dasd_eckd_restore_device(struct dasd_device *device)
 	/* Read Feature Codes */
 	dasd_eckd_read_features(device);
 
+	/* Read Volume Information */
+	rc = dasd_eckd_read_vol_info(device);
+	if (rc)
+		goto out_err2;
+
+	/* Read Extent Pool Information */
+	rc = dasd_eckd_read_ext_pool_info(device);
+	if (rc)
+		goto out_err2;
+
 	/* Read Device Characteristics */
 	rc = dasd_generic_read_dev_chars(device, DASD_ECKD_MAGIC,
 					 &temp_rdc_data, 64);
@@ -5785,6 +6052,15 @@ static struct dasd_discipline dasd_eckd_discipline = {
 	.disable_hpf = dasd_eckd_disable_hpf_device,
 	.hpf_enabled = dasd_eckd_hpf_enabled,
 	.reset_path = dasd_eckd_reset_path,
+	.is_ese = dasd_eckd_is_ese,
+	.space_allocated = dasd_eckd_space_allocated,
+	.space_configured = dasd_eckd_space_configured,
+	.logical_capacity = dasd_eckd_logical_capacity,
+	.ext_pool_id = dasd_eckd_ext_pool_id,
+	.ext_size = dasd_eckd_ext_size,
+	.ext_pool_cap_at_warnlevel = dasd_eckd_ext_pool_cap_at_warnlevel,
+	.ext_pool_warn_thrshld = dasd_eckd_ext_pool_warn_thrshld,
+	.ext_pool_oos = dasd_eckd_ext_pool_oos,
 };
 
 static int __init