[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>
This commit is contained in:
Sebastian Ott 2011-01-05 12:47:56 +01:00 committed by Martin Schwidefsky
parent 37e8952174
commit ce322ccd53
4 changed files with 79 additions and 0 deletions

View file

@ -204,6 +204,8 @@ int ccw_device_tm_start_timeout(struct ccw_device *, struct tcw *,
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);

View file

@ -695,6 +695,25 @@ out:
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)

View file

@ -35,6 +35,22 @@ struct channel_path_desc {
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 chsc_determine_channel_path_desc(struct chp_id chpid, int fmt, int rfmt,
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);

View file

@ -686,6 +686,46 @@ int ccw_device_tm_start_timeout(struct ccw_device *cdev, struct tcw *tcw,
}
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