[S390] cio: obtain mdc value per channel path
Add support to accumulate the number of 64K-bytes blocks all paths
to a device at least support for a transport command.
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/arch/s390/include/asm/ccwdev.h b/arch/s390/include/asm/ccwdev.h
index e850111..ff6f62e 100644
--- a/arch/s390/include/asm/ccwdev.h
+++ b/arch/s390/include/asm/ccwdev.h
@@ -204,6 +204,8 @@
unsigned long, u8, int);
int ccw_device_tm_intrg(struct ccw_device *cdev);
+int ccw_device_get_mdc(struct ccw_device *cdev, u8 mask);
+
extern int ccw_device_set_online(struct ccw_device *cdev);
extern int ccw_device_set_offline(struct ccw_device *cdev);
diff --git a/drivers/s390/cio/chsc.c b/drivers/s390/cio/chsc.c
index 1aaddea..0689fcf 100644
--- a/drivers/s390/cio/chsc.c
+++ b/drivers/s390/cio/chsc.c
@@ -695,6 +695,25 @@
return ret;
}
+int chsc_determine_fmt1_channel_path_desc(struct chp_id chpid,
+ struct channel_path_desc_fmt1 *desc)
+{
+ struct chsc_response_struct *chsc_resp;
+ struct chsc_scpd *scpd_area;
+ int ret;
+
+ spin_lock_irq(&chsc_page_lock);
+ scpd_area = chsc_page;
+ ret = chsc_determine_channel_path_desc(chpid, 0, 0, 1, 0, scpd_area);
+ if (ret)
+ goto out;
+ chsc_resp = (void *)&scpd_area->response;
+ memcpy(desc, &chsc_resp->data, sizeof(*desc));
+out:
+ spin_unlock_irq(&chsc_page_lock);
+ return ret;
+}
+
static void
chsc_initialize_cmg_chars(struct channel_path *chp, u8 cmcv,
struct cmg_chars *chars)
diff --git a/drivers/s390/cio/chsc.h b/drivers/s390/cio/chsc.h
index 6693f5e..3f15b2a 100644
--- a/drivers/s390/cio/chsc.h
+++ b/drivers/s390/cio/chsc.h
@@ -35,6 +35,22 @@
u8 chpp;
} __attribute__ ((packed));
+struct channel_path_desc_fmt1 {
+ u8 flags;
+ u8 lsn;
+ u8 desc;
+ u8 chpid;
+ u32:24;
+ u8 chpp;
+ u32 unused[3];
+ u16 mdc;
+ u16:13;
+ u8 r:1;
+ u8 s:1;
+ u8 f:1;
+ u32 zeros[2];
+} __attribute__ ((packed));
+
struct channel_path;
struct css_chsc_char {
@@ -92,6 +108,8 @@
int c, int m, void *page);
int chsc_determine_base_channel_path_desc(struct chp_id chpid,
struct channel_path_desc *desc);
+int chsc_determine_fmt1_channel_path_desc(struct chp_id chpid,
+ struct channel_path_desc_fmt1 *desc);
void chsc_chp_online(struct chp_id chpid);
void chsc_chp_offline(struct chp_id chpid);
int chsc_get_channel_measurement_chars(struct channel_path *chp);
diff --git a/drivers/s390/cio/device_ops.c b/drivers/s390/cio/device_ops.c
index 6da8454..651976b 100644
--- a/drivers/s390/cio/device_ops.c
+++ b/drivers/s390/cio/device_ops.c
@@ -687,6 +687,46 @@
EXPORT_SYMBOL(ccw_device_tm_start_timeout);
/**
+ * ccw_device_get_mdc - accumulate max data count
+ * @cdev: ccw device for which the max data count is accumulated
+ * @mask: mask of paths to use
+ *
+ * Return the number of 64K-bytes blocks all paths at least support
+ * for a transport command. Return values <= 0 indicate failures.
+ */
+int ccw_device_get_mdc(struct ccw_device *cdev, u8 mask)
+{
+ struct subchannel *sch = to_subchannel(cdev->dev.parent);
+ struct channel_path_desc_fmt1 desc;
+ struct chp_id chpid;
+ int mdc = 0, ret, i;
+
+ /* Adjust requested path mask to excluded varied off paths. */
+ if (mask)
+ mask &= sch->lpm;
+ else
+ mask = sch->lpm;
+
+ chp_id_init(&chpid);
+ for (i = 0; i < 8; i++) {
+ if (!(mask & (0x80 >> i)))
+ continue;
+ chpid.id = sch->schib.pmcw.chpid[i];
+ ret = chsc_determine_fmt1_channel_path_desc(chpid, &desc);
+ if (ret)
+ return ret;
+ if (!desc.f)
+ return 0;
+ if (!desc.r)
+ mdc = 1;
+ mdc = mdc ? min(mdc, (int)desc.mdc) : desc.mdc;
+ }
+
+ return mdc;
+}
+EXPORT_SYMBOL(ccw_device_get_mdc);
+
+/**
* ccw_device_tm_intrg - perform interrogate function
* @cdev: ccw device on which to perform the interrogate function
*