linux/drivers/s390/cio/chp.c
Peter Oberparleiter c9182e0f42 [S390] cio: observe chpid valid flag
Check validity flag of CHPID description data before continuing with
channel-path initialization.

Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2007-04-27 16:01:39 +02:00

438 lines
10 KiB
C

/*
* drivers/s390/cio/chp.c
*
* Copyright IBM Corp. 1999,2007
* Author(s): Cornelia Huck (cornelia.huck@de.ibm.com)
* Arnd Bergmann (arndb@de.ibm.com)
* Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
*/
#include <linux/bug.h>
#include <linux/workqueue.h>
#include <linux/spinlock.h>
#include <asm/errno.h>
#include "chpid.h"
#include "cio.h"
#include "css.h"
#include "ioasm.h"
#include "cio_debug.h"
#include "chp.h"
#define to_channelpath(device) container_of(device, struct channel_path, dev)
/* Return channel_path struct for given chpid. */
static inline struct channel_path *chpid_to_chp(struct chp_id chpid)
{
return css[chpid.cssid]->chps[chpid.id];
}
/* Set vary state for given chpid. */
static void set_chp_logically_online(struct chp_id chpid, int onoff)
{
chpid_to_chp(chpid)->state = onoff;
}
/* On succes return 0 if channel-path is varied offline, 1 if it is varied
* online. Return -ENODEV if channel-path is not registered. */
int chp_get_status(struct chp_id chpid)
{
return (chpid_to_chp(chpid) ? chpid_to_chp(chpid)->state : -ENODEV);
}
/**
* chp_get_sch_opm - return opm for subchannel
* @sch: subchannel
*
* Calculate and return the operational path mask (opm) based on the chpids
* used by the subchannel and the status of the associated channel-paths.
*/
u8 chp_get_sch_opm(struct subchannel *sch)
{
struct chp_id chpid;
int opm;
int i;
opm = 0;
chp_id_init(&chpid);
for (i=0; i < 8; i++) {
opm <<= 1;
chpid.id = sch->schib.pmcw.chpid[i];
if (chp_get_status(chpid) != 0)
opm |= 1;
}
return opm;
}
/**
* chp_is_registered - check if a channel-path is registered
* @chpid: channel-path ID
*
* Return non-zero if a channel-path with the given chpid is registered,
* zero otherwise.
*/
int chp_is_registered(struct chp_id chpid)
{
return chpid_to_chp(chpid) != NULL;
}
/*
* Function: s390_vary_chpid
* Varies the specified chpid online or offline
*/
static int s390_vary_chpid(struct chp_id chpid, int on)
{
char dbf_text[15];
int status;
sprintf(dbf_text, on?"varyon%x.%02x":"varyoff%x.%02x", chpid.cssid,
chpid.id);
CIO_TRACE_EVENT( 2, dbf_text);
status = chp_get_status(chpid);
if (status < 0) {
printk(KERN_ERR "Can't vary unknown chpid %x.%02x\n",
chpid.cssid, chpid.id);
return -EINVAL;
}
if (!on && !status) {
printk(KERN_ERR "chpid %x.%02x is already offline\n",
chpid.cssid, chpid.id);
return -EINVAL;
}
set_chp_logically_online(chpid, on);
chsc_chp_vary(chpid, on);
return 0;
}
/*
* Channel measurement related functions
*/
static ssize_t chp_measurement_chars_read(struct kobject *kobj, char *buf,
loff_t off, size_t count)
{
struct channel_path *chp;
unsigned int size;
chp = to_channelpath(container_of(kobj, struct device, kobj));
if (!chp->cmg_chars)
return 0;
size = sizeof(struct cmg_chars);
if (off > size)
return 0;
if (off + count > size)
count = size - off;
memcpy(buf, chp->cmg_chars + off, count);
return count;
}
static struct bin_attribute chp_measurement_chars_attr = {
.attr = {
.name = "measurement_chars",
.mode = S_IRUSR,
.owner = THIS_MODULE,
},
.size = sizeof(struct cmg_chars),
.read = chp_measurement_chars_read,
};
static void chp_measurement_copy_block(struct cmg_entry *buf,
struct channel_subsystem *css,
struct chp_id chpid)
{
void *area;
struct cmg_entry *entry, reference_buf;
int idx;
if (chpid.id < 128) {
area = css->cub_addr1;
idx = chpid.id;
} else {
area = css->cub_addr2;
idx = chpid.id - 128;
}
entry = area + (idx * sizeof(struct cmg_entry));
do {
memcpy(buf, entry, sizeof(*entry));
memcpy(&reference_buf, entry, sizeof(*entry));
} while (reference_buf.values[0] != buf->values[0]);
}
static ssize_t chp_measurement_read(struct kobject *kobj, char *buf,
loff_t off, size_t count)
{
struct channel_path *chp;
struct channel_subsystem *css;
unsigned int size;
chp = to_channelpath(container_of(kobj, struct device, kobj));
css = to_css(chp->dev.parent);
size = sizeof(struct cmg_entry);
/* Only allow single reads. */
if (off || count < size)
return 0;
chp_measurement_copy_block((struct cmg_entry *)buf, css, chp->chpid);
count = size;
return count;
}
static struct bin_attribute chp_measurement_attr = {
.attr = {
.name = "measurement",
.mode = S_IRUSR,
.owner = THIS_MODULE,
},
.size = sizeof(struct cmg_entry),
.read = chp_measurement_read,
};
void chp_remove_cmg_attr(struct channel_path *chp)
{
device_remove_bin_file(&chp->dev, &chp_measurement_chars_attr);
device_remove_bin_file(&chp->dev, &chp_measurement_attr);
}
int chp_add_cmg_attr(struct channel_path *chp)
{
int ret;
ret = device_create_bin_file(&chp->dev, &chp_measurement_chars_attr);
if (ret)
return ret;
ret = device_create_bin_file(&chp->dev, &chp_measurement_attr);
if (ret)
device_remove_bin_file(&chp->dev, &chp_measurement_chars_attr);
return ret;
}
/*
* Files for the channel path entries.
*/
static ssize_t chp_status_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct channel_path *chp = container_of(dev, struct channel_path, dev);
if (!chp)
return 0;
return (chp_get_status(chp->chpid) ? sprintf(buf, "online\n") :
sprintf(buf, "offline\n"));
}
static ssize_t chp_status_write(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t count)
{
struct channel_path *cp = container_of(dev, struct channel_path, dev);
char cmd[10];
int num_args;
int error;
num_args = sscanf(buf, "%5s", cmd);
if (!num_args)
return count;
if (!strnicmp(cmd, "on", 2) || !strcmp(cmd, "1"))
error = s390_vary_chpid(cp->chpid, 1);
else if (!strnicmp(cmd, "off", 3) || !strcmp(cmd, "0"))
error = s390_vary_chpid(cp->chpid, 0);
else
error = -EINVAL;
return error < 0 ? error : count;
}
static DEVICE_ATTR(status, 0644, chp_status_show, chp_status_write);
static ssize_t chp_type_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct channel_path *chp = container_of(dev, struct channel_path, dev);
if (!chp)
return 0;
return sprintf(buf, "%x\n", chp->desc.desc);
}
static DEVICE_ATTR(type, 0444, chp_type_show, NULL);
static ssize_t chp_cmg_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct channel_path *chp = to_channelpath(dev);
if (!chp)
return 0;
if (chp->cmg == -1) /* channel measurements not available */
return sprintf(buf, "unknown\n");
return sprintf(buf, "%x\n", chp->cmg);
}
static DEVICE_ATTR(cmg, 0444, chp_cmg_show, NULL);
static ssize_t chp_shared_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct channel_path *chp = to_channelpath(dev);
if (!chp)
return 0;
if (chp->shared == -1) /* channel measurements not available */
return sprintf(buf, "unknown\n");
return sprintf(buf, "%x\n", chp->shared);
}
static DEVICE_ATTR(shared, 0444, chp_shared_show, NULL);
static struct attribute * chp_attrs[] = {
&dev_attr_status.attr,
&dev_attr_type.attr,
&dev_attr_cmg.attr,
&dev_attr_shared.attr,
NULL,
};
static struct attribute_group chp_attr_group = {
.attrs = chp_attrs,
};
static void chp_release(struct device *dev)
{
struct channel_path *cp;
cp = container_of(dev, struct channel_path, dev);
kfree(cp);
}
/**
* chp_new - register a new channel-path
* @chpid - channel-path ID
*
* Create and register data structure representing new channel-path. Return
* zero on success, non-zero otherwise.
*/
int chp_new(struct chp_id chpid)
{
struct channel_path *chp;
int ret;
chp = kzalloc(sizeof(struct channel_path), GFP_KERNEL);
if (!chp)
return -ENOMEM;
/* fill in status, etc. */
chp->chpid = chpid;
chp->state = 1;
chp->dev.parent = &css[chpid.cssid]->device;
chp->dev.release = chp_release;
snprintf(chp->dev.bus_id, BUS_ID_SIZE, "chp%x.%02x", chpid.cssid,
chpid.id);
/* Obtain channel path description and fill it in. */
ret = chsc_determine_channel_path_description(chpid, &chp->desc);
if (ret)
goto out_free;
if ((chp->desc.flags & 0x80) == 0) {
ret = -ENODEV;
goto out_free;
}
/* Get channel-measurement characteristics. */
if (css_characteristics_avail && css_chsc_characteristics.scmc
&& css_chsc_characteristics.secm) {
ret = chsc_get_channel_measurement_chars(chp);
if (ret)
goto out_free;
} else {
static int msg_done;
if (!msg_done) {
printk(KERN_WARNING "cio: Channel measurements not "
"available, continuing.\n");
msg_done = 1;
}
chp->cmg = -1;
}
/* make it known to the system */
ret = device_register(&chp->dev);
if (ret) {
printk(KERN_WARNING "%s: could not register %x.%02x\n",
__func__, chpid.cssid, chpid.id);
goto out_free;
}
ret = sysfs_create_group(&chp->dev.kobj, &chp_attr_group);
if (ret) {
device_unregister(&chp->dev);
goto out_free;
}
mutex_lock(&css[chpid.cssid]->mutex);
if (css[chpid.cssid]->cm_enabled) {
ret = chp_add_cmg_attr(chp);
if (ret) {
sysfs_remove_group(&chp->dev.kobj, &chp_attr_group);
device_unregister(&chp->dev);
mutex_unlock(&css[chpid.cssid]->mutex);
goto out_free;
}
}
css[chpid.cssid]->chps[chpid.id] = chp;
mutex_unlock(&css[chpid.cssid]->mutex);
return ret;
out_free:
kfree(chp);
return ret;
}
/**
* chp_get_chp_desc - return newly allocated channel-path description
* @chpid: channel-path ID
*
* On success return a newly allocated copy of the channel-path description
* data associated with the given channel-path ID. Return %NULL on error.
*/
void *chp_get_chp_desc(struct chp_id chpid)
{
struct channel_path *chp;
struct channel_path_desc *desc;
chp = chpid_to_chp(chpid);
if (!chp)
return NULL;
desc = kmalloc(sizeof(struct channel_path_desc), GFP_KERNEL);
if (!desc)
return NULL;
memcpy(desc, &chp->desc, sizeof(struct channel_path_desc));
return desc;
}
/**
* chp_process_crw - process channel-path status change
* @id: channel-path ID number
* @status: non-zero if channel-path has become available, zero otherwise
*
* Handle channel-report-words indicating that the status of a channel-path
* has changed.
*/
int chp_process_crw(int id, int status)
{
struct chp_id chpid;
chp_id_init(&chpid);
chpid.id = id;
if (status) {
if (!chp_is_registered(chpid))
chp_new(chpid);
return chsc_chp_online(chpid);
} else {
chsc_chp_offline(chpid);
return 0;
}
}