[PATCH 5.15 034/317] s390/dasd: add query PPRC function

Sasha Levin
2024-03-24T23:35:33Z

From: Stefan Haberland <sth@linux.ibm.com>

[ Upstream commit 3f217cceb6846e7533511fc69bc774cdba37ff7d ]

Add function to query the Peer-to-Peer-Remote-Copy (PPRC) state of a
device by reading the related structure through a read subsystem data call.

Signed-off-by: Stefan Haberland <sth@linux.ibm.com>
Reviewed-by: Jan Hoeppner <hoeppner@linux.ibm.com>
Link: https://lore.kernel.org/r/20220920192616.808070-3-sth@linux.ibm.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Stable-dep-of: c3116e62ddef ("s390/dasd: fix double module refcount decrement")
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/s390/block/dasd_eckd.c | 66 ++++++++++++++++++++++++++++++++++
drivers/s390/block/dasd_eckd.h | 6 ++++
drivers/s390/block/dasd_int.h | 32 +++++++++++++++++
3 files changed, 104 insertions(+)

diff --git a/drivers/s390/block/dasd_eckd.c b/drivers/s390/block/dasd_eckd.c
index cf80db7a74a3d..76f861c2ce614 100644
--- a/drivers/s390/block/dasd_eckd.c
+++ b/drivers/s390/block/dasd_eckd.c
@@ -6105,6 +6105,71 @@ static int dasd_hosts_print(struct dasd_device *device, struct seq_file *m)
return 0;
}

+/*
+ * Perform Subsystem Function - Peer-to-Peer Remote Copy Extended Query
+ */
+static int dasd_eckd_query_pprc_status(struct dasd_device *device,
+ struct dasd_pprc_data_sc4 *data)
+{
+ struct dasd_pprc_data_sc4 *pprc_data;
+ struct dasd_psf_prssd_data *prssdp;
+ struct dasd_ccw_req *cqr;
+ struct ccw1 *ccw;
+ int rc;
+
+ cqr = dasd_smalloc_request(DASD_ECKD_MAGIC, 1 /* PSF */ + 1 /* RSSD */,
+ sizeof(*prssdp) + sizeof(*pprc_data) + 1,
+ device, NULL);
+ if (IS_ERR(cqr)) {
+ DBF_EVENT_DEVID(DBF_WARNING, device->cdev, "%s",
+ "Could not allocate query PPRC status request");
+ return PTR_ERR(cqr);
+ }
+ 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_PPRCEQ;
+ prssdp->varies[0] = PPRCEQ_SCOPE_4;
+ pprc_data = (struct dasd_pprc_data_sc4 *)(prssdp + 1);
+
+ 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(*pprc_data);
+ ccw->flags |= CCW_FLAG_SLI;
+ ccw->cda = (__u32)(addr_t)pprc_data;
+
+ cqr->buildclk = get_tod_clock();
+ cqr->status = DASD_CQR_FILLED;
+
+ rc = dasd_sleep_on_interruptible(cqr);
+ if (rc == 0) {
+ *data = *pprc_data;
+ } else {
+ DBF_EVENT_DEVID(DBF_WARNING, device->cdev,
+ "PPRC Extended Query failed with rc=%d\n",
+ rc);
+ rc = -EOPNOTSUPP;
+ }
+
+ dasd_sfree_request(cqr, cqr->memdev);
+ return rc;
+}
+
/*
* Perform Subsystem Function - CUIR response
*/
@@ -6723,6 +6788,7 @@ static struct dasd_discipline dasd_eckd_discipline = {
.ext_pool_exhaust = dasd_eckd_ext_pool_exhaust,
.ese_format = dasd_eckd_ese_format,
.ese_read = dasd_eckd_ese_read,
+ .pprc_status = dasd_eckd_query_pprc_status,
};

static int __init
diff --git a/drivers/s390/block/dasd_eckd.h b/drivers/s390/block/dasd_eckd.h
index 65e4630ad2aea..ed83a9a55191b 100644
--- a/drivers/s390/block/dasd_eckd.h
+++ b/drivers/s390/block/dasd_eckd.h
@@ -66,9 +66,15 @@
* Perform Subsystem Function / Sub-Orders
*/
#define PSF_SUBORDER_QHA 0x1C /* Query Host Access */
+#define PSF_SUBORDER_PPRCEQ 0x50 /* PPRC Extended Query */
#define PSF_SUBORDER_VSQ 0x52 /* Volume Storage Query */
#define PSF_SUBORDER_LCQ 0x53 /* Logical Configuration Query */

+/*
+ * PPRC Extended Query Scopes
+ */
+#define PPRCEQ_SCOPE_4 0x04 /* Scope 4 for PPRC Extended Query */
+
/*
* CUIR response condition codes
*/
diff --git a/drivers/s390/block/dasd_int.h b/drivers/s390/block/dasd_int.h
index d94ae067f085e..2ee8bc035b34a 100644
--- a/drivers/s390/block/dasd_int.h
+++ b/drivers/s390/block/dasd_int.h
@@ -260,6 +260,37 @@ struct dasd_uid {
char vduit[33];
};

+/*
+ * PPRC Status data
+ */
+struct dasd_pprc_header {
+ __u8 entries; /* 0 Number of device entries */
+ __u8 unused; /* 1 unused */
+ __u16 entry_length; /* 2-3 Length of device entry */
+ __u32 unused2; /* 4-7 unused */
+} __packed;
+
+struct dasd_pprc_dev_info {
+ __u8 state; /* 0 Copy State */
+ __u8 flags; /* 1 Flags */
+ __u8 reserved1[2]; /* 2-3 reserved */
+ __u8 prim_lss; /* 4 Primary device LSS */
+ __u8 primary; /* 5 Primary device address */
+ __u8 sec_lss; /* 6 Secondary device LSS */
+ __u8 secondary; /* 7 Secondary device address */
+ __u16 pprc_id; /* 8-9 Peer-to-Peer Remote Copy ID */
+ __u8 reserved2[12]; /* 10-21 reserved */
+ __u16 prim_cu_ssid; /* 22-23 Pimary Control Unit SSID */
+ __u8 reserved3[12]; /* 24-35 reserved */
+ __u16 sec_cu_ssid; /* 36-37 Secondary Control Unit SSID */
+ __u8 reserved4[90]; /* 38-127 reserved */
+} __packed;
+
+struct dasd_pprc_data_sc4 {
+ struct dasd_pprc_header header;
+ struct dasd_pprc_dev_info dev_info[5];
+} __packed;
+
/*
* the struct dasd_discipline is
* sth like a table of virtual functions, if you think of dasd_eckd
@@ -388,6 +419,7 @@ struct dasd_discipline {
struct dasd_ccw_req *(*ese_format)(struct dasd_device *,
struct dasd_ccw_req *, struct irb *);
int (*ese_read)(struct dasd_ccw_req *, struct irb *);
+ int (*pprc_status)(struct dasd_device *, struct dasd_pprc_data_sc4 *);
};

extern struct dasd_discipline *dasd_diag_discipline_pointer;
--
2.43.0