s390/dasd: add query host access to volume support
With this feature, applications can query if a DASD volume is online
to another operating system instances by checking the online status of
all attached hosts from the storage server.
Reviewed-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Stefan Haberland <stefan.haberland@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/drivers/s390/block/dasd_eckd.c b/drivers/s390/block/dasd_eckd.c
index c1b4ae5..3b70d37 100644
--- a/drivers/s390/block/dasd_eckd.c
+++ b/drivers/s390/block/dasd_eckd.c
@@ -19,6 +19,7 @@
#include <linux/module.h>
#include <linux/compat.h>
#include <linux/init.h>
+#include <linux/seq_file.h>
#include <asm/css_chars.h>
#include <asm/debug.h>
@@ -4627,6 +4628,167 @@
return rc;
}
+static int dasd_eckd_query_host_access(struct dasd_device *device,
+ struct dasd_psf_query_host_access *data)
+{
+ struct dasd_eckd_private *private = device->private;
+ struct dasd_psf_query_host_access *host_access;
+ struct dasd_psf_prssd_data *prssdp;
+ struct dasd_ccw_req *cqr;
+ struct ccw1 *ccw;
+ int rc;
+
+ /* not available for HYPER PAV alias devices */
+ if (!device->block && private->lcu->pav == HYPER_PAV)
+ return -EOPNOTSUPP;
+
+ cqr = dasd_smalloc_request(DASD_ECKD_MAGIC, 1 /* PSF */ + 1 /* RSSD */,
+ sizeof(struct dasd_psf_prssd_data) + 1,
+ device);
+ if (IS_ERR(cqr)) {
+ DBF_EVENT_DEVID(DBF_WARNING, device->cdev, "%s",
+ "Could not allocate read message buffer request");
+ return PTR_ERR(cqr);
+ }
+ host_access = kzalloc(sizeof(*host_access), GFP_KERNEL | GFP_DMA);
+ if (!host_access) {
+ dasd_sfree_request(cqr, device);
+ DBF_EVENT_DEVID(DBF_WARNING, device->cdev, "%s",
+ "Could not allocate host_access buffer");
+ return -ENOMEM;
+ }
+ cqr->startdev = device;
+ cqr->memdev = device;
+ cqr->block = NULL;
+ cqr->retries = 256;
+ cqr->expires = 10 * HZ;
+
+ /* Prepare for Read Subsystem Data */
+ prssdp = (struct dasd_psf_prssd_data *) cqr->data;
+ memset(prssdp, 0, sizeof(struct dasd_psf_prssd_data));
+ prssdp->order = PSF_ORDER_PRSSD;
+ prssdp->suborder = PSF_SUBORDER_QHA; /* query host access */
+ /* LSS and Volume that will be queried */
+ prssdp->lss = private->ned->ID;
+ prssdp->volume = private->ned->unit_addr;
+ /* all other bytes of prssdp must be zero */
+
+ ccw = cqr->cpaddr;
+ ccw->cmd_code = DASD_ECKD_CCW_PSF;
+ ccw->count = sizeof(struct dasd_psf_prssd_data);
+ ccw->flags |= CCW_FLAG_CC;
+ ccw->flags |= CCW_FLAG_SLI;
+ ccw->cda = (__u32)(addr_t) prssdp;
+
+ /* Read Subsystem Data - query host access */
+ ccw++;
+ ccw->cmd_code = DASD_ECKD_CCW_RSSD;
+ ccw->count = sizeof(struct dasd_psf_query_host_access);
+ ccw->flags |= CCW_FLAG_SLI;
+ ccw->cda = (__u32)(addr_t) host_access;
+
+ cqr->buildclk = get_tod_clock();
+ cqr->status = DASD_CQR_FILLED;
+ rc = dasd_sleep_on(cqr);
+ if (rc == 0) {
+ *data = *host_access;
+ } else {
+ DBF_EVENT_DEVID(DBF_WARNING, device->cdev,
+ "Reading host access data failed with rc=%d\n",
+ rc);
+ rc = -EOPNOTSUPP;
+ }
+
+ dasd_sfree_request(cqr, cqr->memdev);
+ kfree(host_access);
+ return rc;
+}
+/*
+ * return number of grouped devices
+ */
+static int dasd_eckd_host_access_count(struct dasd_device *device)
+{
+ struct dasd_psf_query_host_access *access;
+ struct dasd_ckd_path_group_entry *entry;
+ struct dasd_ckd_host_information *info;
+ int count = 0;
+ int rc, i;
+
+ access = kzalloc(sizeof(*access), GFP_NOIO);
+ if (!access) {
+ DBF_EVENT_DEVID(DBF_WARNING, device->cdev, "%s",
+ "Could not allocate access buffer");
+ return -ENOMEM;
+ }
+ rc = dasd_eckd_query_host_access(device, access);
+ if (rc) {
+ kfree(access);
+ return rc;
+ }
+
+ info = (struct dasd_ckd_host_information *)
+ access->host_access_information;
+ for (i = 0; i < info->entry_count; i++) {
+ entry = (struct dasd_ckd_path_group_entry *)
+ (info->entry + i * info->entry_size);
+ if (entry->status_flags & DASD_ECKD_PG_GROUPED)
+ count++;
+ }
+
+ kfree(access);
+ return count;
+}
+
+/*
+ * write host access information to a sequential file
+ */
+static int dasd_hosts_print(struct dasd_device *device, struct seq_file *m)
+{
+ struct dasd_psf_query_host_access *access;
+ struct dasd_ckd_path_group_entry *entry;
+ struct dasd_ckd_host_information *info;
+ char sysplex[9] = "";
+ int rc, i, j;
+
+ access = kzalloc(sizeof(*access), GFP_NOIO);
+ if (!access) {
+ DBF_EVENT_DEVID(DBF_WARNING, device->cdev, "%s",
+ "Could not allocate access buffer");
+ return -ENOMEM;
+ }
+ rc = dasd_eckd_query_host_access(device, access);
+ if (rc) {
+ kfree(access);
+ return rc;
+ }
+
+ info = (struct dasd_ckd_host_information *)
+ access->host_access_information;
+ for (i = 0; i < info->entry_count; i++) {
+ entry = (struct dasd_ckd_path_group_entry *)
+ (info->entry + i * info->entry_size);
+ /* PGID */
+ seq_puts(m, "pgid ");
+ for (j = 0; j < 11; j++)
+ seq_printf(m, "%02x", entry->pgid[j]);
+ seq_putc(m, '\n');
+ /* FLAGS */
+ seq_printf(m, "status_flags %02x\n", entry->status_flags);
+ /* SYSPLEX NAME */
+ memcpy(&sysplex, &entry->sysplex_name, sizeof(sysplex) - 1);
+ EBCASC(sysplex, sizeof(sysplex));
+ seq_printf(m, "sysplex_name %8s\n", sysplex);
+ /* SUPPORTED CYLINDER */
+ seq_printf(m, "supported_cylinder %d\n", entry->cylinder);
+ /* TIMESTAMP */
+ seq_printf(m, "timestamp %lu\n", (unsigned long)
+ entry->timestamp);
+ }
+ kfree(access);
+
+ return 0;
+}
+
/*
* Perform Subsystem Function - CUIR response
*/
@@ -5099,6 +5261,8 @@
.get_uid = dasd_eckd_get_uid,
.kick_validate = dasd_eckd_kick_validate_server,
.check_attention = dasd_eckd_check_attention,
+ .host_access_count = dasd_eckd_host_access_count,
+ .hosts_print = dasd_hosts_print,
};
static int __init