kernel-ark/drivers/s390/char/sclp_chp.c
Heiko Carstens 83119ad4a1 [S390] sclp: Test facility list before executing a service call.
Check if a command is available before executing. Saves some
superfluous service calls that won't succeed anyway.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2007-07-10 11:24:43 +02:00

201 lines
5.0 KiB
C

/*
* drivers/s390/char/sclp_chp.c
*
* Copyright IBM Corp. 2007
* Author(s): Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
*/
#include <linux/types.h>
#include <linux/gfp.h>
#include <linux/errno.h>
#include <linux/completion.h>
#include <asm/sclp.h>
#include <asm/chpid.h>
#include "sclp.h"
#define TAG "sclp_chp: "
#define SCLP_CMDW_CONFIGURE_CHANNEL_PATH 0x000f0001
#define SCLP_CMDW_DECONFIGURE_CHANNEL_PATH 0x000e0001
#define SCLP_CMDW_READ_CHANNEL_PATH_INFORMATION 0x00030001
static inline sclp_cmdw_t get_configure_cmdw(struct chp_id chpid)
{
return SCLP_CMDW_CONFIGURE_CHANNEL_PATH | chpid.id << 8;
}
static inline sclp_cmdw_t get_deconfigure_cmdw(struct chp_id chpid)
{
return SCLP_CMDW_DECONFIGURE_CHANNEL_PATH | chpid.id << 8;
}
static void chp_callback(struct sclp_req *req, void *data)
{
struct completion *completion = data;
complete(completion);
}
struct chp_cfg_sccb {
struct sccb_header header;
u8 ccm;
u8 reserved[6];
u8 cssid;
} __attribute__((packed));
struct chp_cfg_data {
struct chp_cfg_sccb sccb;
struct sclp_req req;
struct completion completion;
} __attribute__((packed));
static int do_configure(sclp_cmdw_t cmd)
{
struct chp_cfg_data *data;
int rc;
if (!SCLP_HAS_CHP_RECONFIG)
return -EOPNOTSUPP;
/* Prepare sccb. */
data = (struct chp_cfg_data *) get_zeroed_page(GFP_KERNEL | GFP_DMA);
if (!data)
return -ENOMEM;
data->sccb.header.length = sizeof(struct chp_cfg_sccb);
data->req.command = cmd;
data->req.sccb = &(data->sccb);
data->req.status = SCLP_REQ_FILLED;
data->req.callback = chp_callback;
data->req.callback_data = &(data->completion);
init_completion(&data->completion);
/* Perform sclp request. */
rc = sclp_add_request(&(data->req));
if (rc)
goto out;
wait_for_completion(&data->completion);
/* Check response .*/
if (data->req.status != SCLP_REQ_DONE) {
printk(KERN_WARNING TAG "configure channel-path request failed "
"(status=0x%02x)\n", data->req.status);
rc = -EIO;
goto out;
}
switch (data->sccb.header.response_code) {
case 0x0020:
case 0x0120:
case 0x0440:
case 0x0450:
break;
default:
printk(KERN_WARNING TAG "configure channel-path failed "
"(cmd=0x%08x, response=0x%04x)\n", cmd,
data->sccb.header.response_code);
rc = -EIO;
break;
}
out:
free_page((unsigned long) data);
return rc;
}
/**
* sclp_chp_configure - perform configure channel-path sclp command
* @chpid: channel-path ID
*
* Perform configure channel-path command sclp command for specified chpid.
* Return 0 after command successfully finished, non-zero otherwise.
*/
int sclp_chp_configure(struct chp_id chpid)
{
return do_configure(get_configure_cmdw(chpid));
}
/**
* sclp_chp_deconfigure - perform deconfigure channel-path sclp command
* @chpid: channel-path ID
*
* Perform deconfigure channel-path command sclp command for specified chpid
* and wait for completion. On success return 0. Return non-zero otherwise.
*/
int sclp_chp_deconfigure(struct chp_id chpid)
{
return do_configure(get_deconfigure_cmdw(chpid));
}
struct chp_info_sccb {
struct sccb_header header;
u8 recognized[SCLP_CHP_INFO_MASK_SIZE];
u8 standby[SCLP_CHP_INFO_MASK_SIZE];
u8 configured[SCLP_CHP_INFO_MASK_SIZE];
u8 ccm;
u8 reserved[6];
u8 cssid;
} __attribute__((packed));
struct chp_info_data {
struct chp_info_sccb sccb;
struct sclp_req req;
struct completion completion;
} __attribute__((packed));
/**
* sclp_chp_read_info - perform read channel-path information sclp command
* @info: resulting channel-path information data
*
* Perform read channel-path information sclp command and wait for completion.
* On success, store channel-path information in @info and return 0. Return
* non-zero otherwise.
*/
int sclp_chp_read_info(struct sclp_chp_info *info)
{
struct chp_info_data *data;
int rc;
if (!SCLP_HAS_CHP_INFO)
return -EOPNOTSUPP;
/* Prepare sccb. */
data = (struct chp_info_data *) get_zeroed_page(GFP_KERNEL | GFP_DMA);
if (!data)
return -ENOMEM;
data->sccb.header.length = sizeof(struct chp_info_sccb);
data->req.command = SCLP_CMDW_READ_CHANNEL_PATH_INFORMATION;
data->req.sccb = &(data->sccb);
data->req.status = SCLP_REQ_FILLED;
data->req.callback = chp_callback;
data->req.callback_data = &(data->completion);
init_completion(&data->completion);
/* Perform sclp request. */
rc = sclp_add_request(&(data->req));
if (rc)
goto out;
wait_for_completion(&data->completion);
/* Check response .*/
if (data->req.status != SCLP_REQ_DONE) {
printk(KERN_WARNING TAG "read channel-path info request failed "
"(status=0x%02x)\n", data->req.status);
rc = -EIO;
goto out;
}
if (data->sccb.header.response_code != 0x0010) {
printk(KERN_WARNING TAG "read channel-path info failed "
"(response=0x%04x)\n", data->sccb.header.response_code);
rc = -EIO;
goto out;
}
memcpy(info->recognized, data->sccb.recognized,
SCLP_CHP_INFO_MASK_SIZE);
memcpy(info->standby, data->sccb.standby,
SCLP_CHP_INFO_MASK_SIZE);
memcpy(info->configured, data->sccb.configured,
SCLP_CHP_INFO_MASK_SIZE);
out:
free_page((unsigned long) data);
return rc;
}