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-rw-r--r--drivers/s390/block/dasd.c3
-rw-r--r--drivers/s390/block/dasd_devmap.c1
-rw-r--r--drivers/s390/block/dasd_eckd.c94
-rw-r--r--drivers/s390/block/dasd_int.h20
4 files changed, 117 insertions, 1 deletions
diff --git a/drivers/s390/block/dasd.c b/drivers/s390/block/dasd.c
index ea82821599f6..c03f26e79f45 100644
--- a/drivers/s390/block/dasd.c
+++ b/drivers/s390/block/dasd.c
@@ -3927,7 +3927,7 @@ EXPORT_SYMBOL_GPL(dasd_generic_space_avail);
/*
* clear active requests and requeue them to block layer if possible
*/
-static int dasd_generic_requeue_all_requests(struct dasd_device *device)
+int dasd_generic_requeue_all_requests(struct dasd_device *device)
{
struct list_head requeue_queue;
struct dasd_ccw_req *cqr, *n;
@@ -4001,6 +4001,7 @@ static int dasd_generic_requeue_all_requests(struct dasd_device *device)
dasd_schedule_device_bh(device);
return rc;
}
+EXPORT_SYMBOL_GPL(dasd_generic_requeue_all_requests);
static void do_requeue_requests(struct work_struct *work)
{
diff --git a/drivers/s390/block/dasd_devmap.c b/drivers/s390/block/dasd_devmap.c
index 28c244aa75cf..ca5c9e963662 100644
--- a/drivers/s390/block/dasd_devmap.c
+++ b/drivers/s390/block/dasd_devmap.c
@@ -937,6 +937,7 @@ void dasd_add_link_to_gendisk(struct gendisk *gdp, struct dasd_device *device)
gdp->private_data = devmap;
spin_unlock(&dasd_devmap_lock);
}
+EXPORT_SYMBOL(dasd_add_link_to_gendisk);
struct dasd_device *dasd_device_from_gendisk(struct gendisk *gdp)
{
diff --git a/drivers/s390/block/dasd_eckd.c b/drivers/s390/block/dasd_eckd.c
index c8a226f070fa..d4d3bd33553b 100644
--- a/drivers/s390/block/dasd_eckd.c
+++ b/drivers/s390/block/dasd_eckd.c
@@ -6119,6 +6119,99 @@ static int dasd_hosts_print(struct dasd_device *device, struct seq_file *m)
return 0;
}
+static struct dasd_device
+*copy_relation_find_device(struct dasd_copy_relation *copy,
+ char *busid)
+{
+ int i;
+
+ for (i = 0; i < DASD_CP_ENTRIES; i++) {
+ if (copy->entry[i].configured &&
+ strncmp(copy->entry[i].busid, busid, DASD_BUS_ID_SIZE) == 0)
+ return copy->entry[i].device;
+ }
+ return NULL;
+}
+
+/*
+ * set the new active/primary device
+ */
+static void copy_pair_set_active(struct dasd_copy_relation *copy, char *new_busid,
+ char *old_busid)
+{
+ int i;
+
+ for (i = 0; i < DASD_CP_ENTRIES; i++) {
+ if (copy->entry[i].configured &&
+ strncmp(copy->entry[i].busid, new_busid,
+ DASD_BUS_ID_SIZE) == 0) {
+ copy->active = &copy->entry[i];
+ copy->entry[i].primary = true;
+ } else if (copy->entry[i].configured &&
+ strncmp(copy->entry[i].busid, old_busid,
+ DASD_BUS_ID_SIZE) == 0) {
+ copy->entry[i].primary = false;
+ }
+ }
+}
+
+/*
+ * The function will swap the role of a given copy pair.
+ * During the swap operation the relation of the blockdevice is disconnected
+ * from the old primary and connected to the new.
+ *
+ * IO is paused on the block queue before swap and may be resumed afterwards.
+ */
+static int dasd_eckd_copy_pair_swap(struct dasd_device *device, char *prim_busid,
+ char *sec_busid)
+{
+ struct dasd_device *primary, *secondary;
+ struct dasd_copy_relation *copy;
+ struct dasd_block *block;
+ struct gendisk *gdp;
+
+ copy = device->copy;
+ if (!copy)
+ return DASD_COPYPAIRSWAP_INVALID;
+ primary = copy->active->device;
+ if (!primary)
+ return DASD_COPYPAIRSWAP_INVALID;
+ /* double check if swap has correct primary */
+ if (strncmp(dev_name(&primary->cdev->dev), prim_busid, DASD_BUS_ID_SIZE) != 0)
+ return DASD_COPYPAIRSWAP_PRIMARY;
+
+ secondary = copy_relation_find_device(copy, sec_busid);
+ if (!secondary)
+ return DASD_COPYPAIRSWAP_SECONDARY;
+
+ /*
+ * usually the device should be quiesced for swap
+ * for paranoia stop device and requeue requests again
+ */
+ dasd_device_set_stop_bits(primary, DASD_STOPPED_PPRC);
+ dasd_device_set_stop_bits(secondary, DASD_STOPPED_PPRC);
+ dasd_generic_requeue_all_requests(primary);
+
+ /* swap DASD internal device <> block assignment */
+ block = primary->block;
+ primary->block = NULL;
+ secondary->block = block;
+ block->base = secondary;
+ /* set new primary device in COPY relation */
+ copy_pair_set_active(copy, sec_busid, prim_busid);
+
+ /* swap blocklayer device link */
+ gdp = block->gdp;
+ dasd_add_link_to_gendisk(gdp, secondary);
+
+ /* re-enable device */
+ dasd_device_remove_stop_bits(primary, DASD_STOPPED_PPRC);
+ dasd_device_remove_stop_bits(secondary, DASD_STOPPED_PPRC);
+ dasd_schedule_device_bh(secondary);
+
+ return DASD_COPYPAIRSWAP_SUCCESS;
+}
+
/*
* Perform Subsystem Function - Peer-to-Peer Remote Copy Extended Query
*/
@@ -6805,6 +6898,7 @@ static struct dasd_discipline dasd_eckd_discipline = {
.ese_read = dasd_eckd_ese_read,
.pprc_status = dasd_eckd_query_pprc_status,
.pprc_enabled = dasd_eckd_pprc_enabled,
+ .copy_pair_swap = dasd_eckd_copy_pair_swap,
};
static int __init
diff --git a/drivers/s390/block/dasd_int.h b/drivers/s390/block/dasd_int.h
index d9794ec03722..3c55c29155ef 100644
--- a/drivers/s390/block/dasd_int.h
+++ b/drivers/s390/block/dasd_int.h
@@ -438,6 +438,7 @@ struct dasd_discipline {
int (*ese_read)(struct dasd_ccw_req *, struct irb *);
int (*pprc_status)(struct dasd_device *, struct dasd_pprc_data_sc4 *);
bool (*pprc_enabled)(struct dasd_device *);
+ int (*copy_pair_swap)(struct dasd_device *, char *, char *);
};
extern struct dasd_discipline *dasd_diag_discipline_pointer;
@@ -681,6 +682,7 @@ struct dasd_queue {
#define DASD_STOPPED_PENDING 4 /* long busy */
#define DASD_STOPPED_DC_WAIT 8 /* disconnected, wait */
#define DASD_STOPPED_SU 16 /* summary unit check handling */
+#define DASD_STOPPED_PPRC 32 /* PPRC swap */
#define DASD_STOPPED_NOSPC 128 /* no space left */
/* per device flags */
@@ -706,6 +708,22 @@ struct dasd_queue {
void dasd_put_device_wake(struct dasd_device *);
/*
+ * return values to be returned from the copy pair swap function
+ * 0x00: swap successful
+ * 0x01: swap data invalid
+ * 0x02: no active device found
+ * 0x03: wrong primary specified
+ * 0x04: secondary device not found
+ * 0x05: swap already running
+ */
+#define DASD_COPYPAIRSWAP_SUCCESS 0
+#define DASD_COPYPAIRSWAP_INVALID 1
+#define DASD_COPYPAIRSWAP_NOACTIVE 2
+#define DASD_COPYPAIRSWAP_PRIMARY 3
+#define DASD_COPYPAIRSWAP_SECONDARY 4
+#define DASD_COPYPAIRSWAP_MULTIPLE 5
+
+/*
* Reference count inliners
*/
static inline void
@@ -889,6 +907,8 @@ int dasd_generic_verify_path(struct dasd_device *, __u8);
void dasd_generic_space_exhaust(struct dasd_device *, struct dasd_ccw_req *);
void dasd_generic_space_avail(struct dasd_device *);
+int dasd_generic_requeue_all_requests(struct dasd_device *);
+
int dasd_generic_read_dev_chars(struct dasd_device *, int, void *, int);
char *dasd_get_sense(struct irb *);
generated by cgit v1.2.3 (git 2.39.0) at 2024-08-08 23:22:42 +0300