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remarkable-linux/drivers/s390/block/dasd_devmap.c

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/*
* File...........: linux/drivers/s390/block/dasd_devmap.c
* Author(s)......: Holger Smolinski <Holger.Smolinski@de.ibm.com>
* Horst Hummel <Horst.Hummel@de.ibm.com>
* Carsten Otte <Cotte@de.ibm.com>
* Martin Schwidefsky <schwidefsky@de.ibm.com>
* Bugreports.to..: <Linux390@de.ibm.com>
* (C) IBM Corporation, IBM Deutschland Entwicklung GmbH, 1999-2001
*
* Device mapping and dasd= parameter parsing functions. All devmap
* functions may not be called from interrupt context. In particular
* dasd_get_device is a no-no from interrupt context.
*
*/
#include <linux/ctype.h>
#include <linux/init.h>
#include <linux/module.h>
#include <asm/debug.h>
#include <asm/uaccess.h>
#include <asm/ipl.h>
/* This is ugly... */
#define PRINTK_HEADER "dasd_devmap:"
#define DASD_BUS_ID_SIZE 20
#include "dasd_int.h"
struct kmem_cache *dasd_page_cache;
EXPORT_SYMBOL_GPL(dasd_page_cache);
/*
* dasd_devmap_t is used to store the features and the relation
* between device number and device index. To find a dasd_devmap_t
* that corresponds to a device number of a device index each
* dasd_devmap_t is added to two linked lists, one to search by
* the device number and one to search by the device index. As
* soon as big minor numbers are available the device index list
* can be removed since the device number will then be identical
* to the device index.
*/
struct dasd_devmap {
struct list_head list;
char bus_id[DASD_BUS_ID_SIZE];
unsigned int devindex;
unsigned short features;
struct dasd_device *device;
struct dasd_uid uid;
};
/*
* Parameter parsing functions for dasd= parameter. The syntax is:
* <devno> : (0x)?[0-9a-fA-F]+
* <busid> : [0-0a-f]\.[0-9a-f]\.(0x)?[0-9a-fA-F]+
* <feature> : ro
* <feature_list> : \(<feature>(:<feature>)*\)
* <devno-range> : <devno>(-<devno>)?<feature_list>?
* <busid-range> : <busid>(-<busid>)?<feature_list>?
* <devices> : <devno-range>|<busid-range>
* <dasd_module> : dasd_diag_mod|dasd_eckd_mod|dasd_fba_mod
*
* <dasd> : autodetect|probeonly|<devices>(,<devices>)*
*/
int dasd_probeonly = 0; /* is true, when probeonly mode is active */
int dasd_autodetect = 0; /* is true, when autodetection is active */
int dasd_nopav = 0; /* is true, when PAV is disabled */
EXPORT_SYMBOL_GPL(dasd_nopav);
/*
* char *dasd[] is intended to hold the ranges supplied by the dasd= statement
* it is named 'dasd' to directly be filled by insmod with the comma separated
* strings when running as a module.
*/
static char *dasd[256];
module_param_array(dasd, charp, NULL, 0);
/*
* Single spinlock to protect devmap and servermap structures and lists.
*/
static DEFINE_SPINLOCK(dasd_devmap_lock);
/*
* Hash lists for devmap structures.
*/
static struct list_head dasd_hashlists[256];
int dasd_max_devindex;
static struct dasd_devmap *dasd_add_busid(const char *, int);
static inline int
dasd_hash_busid(const char *bus_id)
{
int hash, i;
hash = 0;
for (i = 0; (i < DASD_BUS_ID_SIZE) && *bus_id; i++, bus_id++)
hash += *bus_id;
return hash & 0xff;
}
#ifndef MODULE
/*
* The parameter parsing functions for builtin-drivers are called
* before kmalloc works. Store the pointers to the parameters strings
* into dasd[] for later processing.
*/
static int __init
dasd_call_setup(char *str)
{
static int count = 0;
if (count < 256)
dasd[count++] = str;
return 1;
}
__setup ("dasd=", dasd_call_setup);
#endif /* #ifndef MODULE */
#define DASD_IPLDEV "ipldev"
/*
* Read a device busid/devno from a string.
*/
static int
dasd_busid(char **str, int *id0, int *id1, int *devno)
{
int val, old_style;
/* Interpret ipldev busid */
if (strncmp(DASD_IPLDEV, *str, strlen(DASD_IPLDEV)) == 0) {
if (ipl_info.type != IPL_TYPE_CCW) {
MESSAGE(KERN_ERR, "%s", "ipl device is not a ccw "
"device");
return -EINVAL;
}
*id0 = 0;
*id1 = ipl_info.data.ccw.dev_id.ssid;
*devno = ipl_info.data.ccw.dev_id.devno;
*str += strlen(DASD_IPLDEV);
return 0;
}
/* check for leading '0x' */
old_style = 0;
if ((*str)[0] == '0' && (*str)[1] == 'x') {
*str += 2;
old_style = 1;
}
if (!isxdigit((*str)[0])) /* We require at least one hex digit */
return -EINVAL;
val = simple_strtoul(*str, str, 16);
if (old_style || (*str)[0] != '.') {
*id0 = *id1 = 0;
if (val < 0 || val > 0xffff)
return -EINVAL;
*devno = val;
return 0;
}
/* New style x.y.z busid */
if (val < 0 || val > 0xff)
return -EINVAL;
*id0 = val;
(*str)++;
if (!isxdigit((*str)[0])) /* We require at least one hex digit */
return -EINVAL;
val = simple_strtoul(*str, str, 16);
if (val < 0 || val > 0xff || (*str)++[0] != '.')
return -EINVAL;
*id1 = val;
if (!isxdigit((*str)[0])) /* We require at least one hex digit */
return -EINVAL;
val = simple_strtoul(*str, str, 16);
if (val < 0 || val > 0xffff)
return -EINVAL;
*devno = val;
return 0;
}
/*
* Read colon separated list of dasd features. Currently there is
* only one: "ro" for read-only devices. The default feature set
* is empty (value 0).
*/
static int
dasd_feature_list(char *str, char **endp)
{
int features, len, rc;
rc = 0;
if (*str != '(') {
*endp = str;
return DASD_FEATURE_DEFAULT;
}
str++;
features = 0;
while (1) {
for (len = 0;
str[len] && str[len] != ':' && str[len] != ')'; len++);
if (len == 2 && !strncmp(str, "ro", 2))
features |= DASD_FEATURE_READONLY;
else if (len == 4 && !strncmp(str, "diag", 4))
features |= DASD_FEATURE_USEDIAG;
else if (len == 6 && !strncmp(str, "erplog", 6))
features |= DASD_FEATURE_ERPLOG;
else if (len == 8 && !strncmp(str, "failfast", 8))
features |= DASD_FEATURE_FAILFAST;
else {
MESSAGE(KERN_WARNING,
"unsupported feature: %*s, "
"ignoring setting", len, str);
rc = -EINVAL;
}
str += len;
if (*str != ':')
break;
str++;
}
if (*str != ')') {
MESSAGE(KERN_WARNING, "%s",
"missing ')' in dasd parameter string\n");
rc = -EINVAL;
} else
str++;
*endp = str;
if (rc != 0)
return rc;
return features;
}
/*
* Try to match the first element on the comma separated parse string
* with one of the known keywords. If a keyword is found, take the approprate
* action and return a pointer to the residual string. If the first element
* could not be matched to any keyword then return an error code.
*/
static char *
dasd_parse_keyword( char *parsestring ) {
char *nextcomma, *residual_str;
int length;
nextcomma = strchr(parsestring,',');
if (nextcomma) {
length = nextcomma - parsestring;
residual_str = nextcomma + 1;
} else {
length = strlen(parsestring);
residual_str = parsestring + length;
}
if (strncmp("autodetect", parsestring, length) == 0) {
dasd_autodetect = 1;
MESSAGE (KERN_INFO, "%s",
"turning to autodetection mode");
return residual_str;
}
if (strncmp("probeonly", parsestring, length) == 0) {
dasd_probeonly = 1;
MESSAGE(KERN_INFO, "%s",
"turning to probeonly mode");
return residual_str;
}
if (strncmp("nopav", parsestring, length) == 0) {
if (MACHINE_IS_VM)
MESSAGE(KERN_INFO, "%s", "'nopav' not supported on VM");
else {
dasd_nopav = 1;
MESSAGE(KERN_INFO, "%s", "disable PAV mode");
}
return residual_str;
}
if (strncmp("fixedbuffers", parsestring, length) == 0) {
if (dasd_page_cache)
return residual_str;
dasd_page_cache =
kmem_cache_create("dasd_page_cache", PAGE_SIZE,
PAGE_SIZE, SLAB_CACHE_DMA,
NULL);
if (!dasd_page_cache)
MESSAGE(KERN_WARNING, "%s", "Failed to create slab, "
"fixed buffer mode disabled.");
else
MESSAGE (KERN_INFO, "%s",
"turning on fixed buffer mode");
return residual_str;
}
return ERR_PTR(-EINVAL);
}
/*
* Try to interprete the first element on the comma separated parse string
* as a device number or a range of devices. If the interpretation is
* successfull, create the matching dasd_devmap entries and return a pointer
* to the residual string.
* If interpretation fails or in case of an error, return an error code.
*/
static char *
dasd_parse_range( char *parsestring ) {
struct dasd_devmap *devmap;
int from, from_id0, from_id1;
int to, to_id0, to_id1;
int features, rc;
char bus_id[DASD_BUS_ID_SIZE+1], *str;
str = parsestring;
rc = dasd_busid(&str, &from_id0, &from_id1, &from);
if (rc == 0) {
to = from;
to_id0 = from_id0;
to_id1 = from_id1;
if (*str == '-') {
str++;
rc = dasd_busid(&str, &to_id0, &to_id1, &to);
}
}
if (rc == 0 &&
(from_id0 != to_id0 || from_id1 != to_id1 || from > to))
rc = -EINVAL;
if (rc) {
MESSAGE(KERN_ERR, "Invalid device range %s", parsestring);
return ERR_PTR(rc);
}
features = dasd_feature_list(str, &str);
if (features < 0)
return ERR_PTR(-EINVAL);
/* each device in dasd= parameter should be set initially online */
features |= DASD_FEATURE_INITIAL_ONLINE;
while (from <= to) {
sprintf(bus_id, "%01x.%01x.%04x",
from_id0, from_id1, from++);
devmap = dasd_add_busid(bus_id, features);
if (IS_ERR(devmap))
return (char *)devmap;
}
if (*str == ',')
return str + 1;
if (*str == '\0')
return str;
MESSAGE(KERN_WARNING,
"junk at end of dasd parameter string: %s\n", str);
return ERR_PTR(-EINVAL);
}
static char *
dasd_parse_next_element( char *parsestring ) {
char * residual_str;
residual_str = dasd_parse_keyword(parsestring);
if (!IS_ERR(residual_str))
return residual_str;
residual_str = dasd_parse_range(parsestring);
return residual_str;
}
/*
* Parse parameters stored in dasd[]
* The 'dasd=...' parameter allows to specify a comma separated list of
* keywords and device ranges. When the dasd driver is build into the kernel,
* the complete list will be stored as one element of the dasd[] array.
* When the dasd driver is build as a module, then the list is broken into
* it's elements and each dasd[] entry contains one element.
*/
int
dasd_parse(void)
{
int rc, i;
char *parsestring;
rc = 0;
for (i = 0; i < 256; i++) {
if (dasd[i] == NULL)
break;
parsestring = dasd[i];
/* loop over the comma separated list in the parsestring */
while (*parsestring) {
parsestring = dasd_parse_next_element(parsestring);
if(IS_ERR(parsestring)) {
rc = PTR_ERR(parsestring);
break;
}
}
if (rc) {
DBF_EVENT(DBF_ALERT, "%s", "invalid range found");
break;
}
}
return rc;
}
/*
* Add a devmap for the device specified by busid. It is possible that
* the devmap already exists (dasd= parameter). The order of the devices
* added through this function will define the kdevs for the individual
* devices.
*/
static struct dasd_devmap *
dasd_add_busid(const char *bus_id, int features)
{
struct dasd_devmap *devmap, *new, *tmp;
int hash;
new = (struct dasd_devmap *)
kzalloc(sizeof(struct dasd_devmap), GFP_KERNEL);
if (!new)
return ERR_PTR(-ENOMEM);
spin_lock(&dasd_devmap_lock);
devmap = NULL;
hash = dasd_hash_busid(bus_id);
list_for_each_entry(tmp, &dasd_hashlists[hash], list)
if (strncmp(tmp->bus_id, bus_id, DASD_BUS_ID_SIZE) == 0) {
devmap = tmp;
break;
}
if (!devmap) {
/* This bus_id is new. */
new->devindex = dasd_max_devindex++;
strncpy(new->bus_id, bus_id, DASD_BUS_ID_SIZE);
new->features = features;
new->device = NULL;
list_add(&new->list, &dasd_hashlists[hash]);
devmap = new;
new = NULL;
}
spin_unlock(&dasd_devmap_lock);
kfree(new);
return devmap;
}
/*
* Find devmap for device with given bus_id.
*/
static struct dasd_devmap *
dasd_find_busid(const char *bus_id)
{
struct dasd_devmap *devmap, *tmp;
int hash;
spin_lock(&dasd_devmap_lock);
devmap = ERR_PTR(-ENODEV);
hash = dasd_hash_busid(bus_id);
list_for_each_entry(tmp, &dasd_hashlists[hash], list) {
if (strncmp(tmp->bus_id, bus_id, DASD_BUS_ID_SIZE) == 0) {
devmap = tmp;
break;
}
}
spin_unlock(&dasd_devmap_lock);
return devmap;
}
/*
* Check if busid has been added to the list of dasd ranges.
*/
int
dasd_busid_known(const char *bus_id)
{
return IS_ERR(dasd_find_busid(bus_id)) ? -ENOENT : 0;
}
/*
* Forget all about the device numbers added so far.
* This may only be called at module unload or system shutdown.
*/
static void
dasd_forget_ranges(void)
{
struct dasd_devmap *devmap, *n;
int i;
spin_lock(&dasd_devmap_lock);
for (i = 0; i < 256; i++) {
list_for_each_entry_safe(devmap, n, &dasd_hashlists[i], list) {
BUG_ON(devmap->device != NULL);
list_del(&devmap->list);
kfree(devmap);
}
}
spin_unlock(&dasd_devmap_lock);
}
/*
* Find the device struct by its device index.
*/
struct dasd_device *
dasd_device_from_devindex(int devindex)
{
struct dasd_devmap *devmap, *tmp;
struct dasd_device *device;
int i;
spin_lock(&dasd_devmap_lock);
devmap = NULL;
for (i = 0; (i < 256) && !devmap; i++)
list_for_each_entry(tmp, &dasd_hashlists[i], list)
if (tmp->devindex == devindex) {
/* Found the devmap for the device. */
devmap = tmp;
break;
}
if (devmap && devmap->device) {
device = devmap->device;
dasd_get_device(device);
} else
device = ERR_PTR(-ENODEV);
spin_unlock(&dasd_devmap_lock);
return device;
}
/*
* Return devmap for cdev. If no devmap exists yet, create one and
* connect it to the cdev.
*/
static struct dasd_devmap *
dasd_devmap_from_cdev(struct ccw_device *cdev)
{
struct dasd_devmap *devmap;
devmap = dasd_find_busid(dev_name(&cdev->dev));
if (IS_ERR(devmap))
devmap = dasd_add_busid(dev_name(&cdev->dev),
DASD_FEATURE_DEFAULT);
return devmap;
}
/*
* Create a dasd device structure for cdev.
*/
struct dasd_device *
dasd_create_device(struct ccw_device *cdev)
{
struct dasd_devmap *devmap;
struct dasd_device *device;
unsigned long flags;
int rc;
devmap = dasd_devmap_from_cdev(cdev);
if (IS_ERR(devmap))
return (void *) devmap;
device = dasd_alloc_device();
if (IS_ERR(device))
return device;
atomic_set(&device->ref_count, 3);
spin_lock(&dasd_devmap_lock);
if (!devmap->device) {
devmap->device = device;
device->devindex = devmap->devindex;
device->features = devmap->features;
get_device(&cdev->dev);
device->cdev = cdev;
rc = 0;
} else
/* Someone else was faster. */
rc = -EBUSY;
spin_unlock(&dasd_devmap_lock);
if (rc) {
dasd_free_device(device);
return ERR_PTR(rc);
}
spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
dev_set_drvdata(&cdev->dev, device);
spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
return device;
}
/*
* Wait queue for dasd_delete_device waits.
*/
static DECLARE_WAIT_QUEUE_HEAD(dasd_delete_wq);
/*
* Remove a dasd device structure. The passed referenced
* is destroyed.
*/
void
dasd_delete_device(struct dasd_device *device)
{
struct ccw_device *cdev;
struct dasd_devmap *devmap;
unsigned long flags;
/* First remove device pointer from devmap. */
devmap = dasd_find_busid(dev_name(&device->cdev->dev));
BUG_ON(IS_ERR(devmap));
spin_lock(&dasd_devmap_lock);
if (devmap->device != device) {
spin_unlock(&dasd_devmap_lock);
dasd_put_device(device);
return;
}
devmap->device = NULL;
spin_unlock(&dasd_devmap_lock);
/* Disconnect dasd_device structure from ccw_device structure. */
spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags);
dev_set_drvdata(&device->cdev->dev, NULL);
spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
/*
* Drop ref_count by 3, one for the devmap reference, one for
* the cdev reference and one for the passed reference.
*/
atomic_sub(3, &device->ref_count);
/* Wait for reference counter to drop to zero. */
wait_event(dasd_delete_wq, atomic_read(&device->ref_count) == 0);
/* Disconnect dasd_device structure from ccw_device structure. */
cdev = device->cdev;
device->cdev = NULL;
/* Put ccw_device structure. */
put_device(&cdev->dev);
/* Now the device structure can be freed. */
dasd_free_device(device);
}
/*
* Reference counter dropped to zero. Wake up waiter
* in dasd_delete_device.
*/
void
dasd_put_device_wake(struct dasd_device *device)
{
wake_up(&dasd_delete_wq);
}
/*
* Return dasd_device structure associated with cdev.
* This function needs to be called with the ccw device
* lock held. It can be used from interrupt context.
*/
struct dasd_device *
dasd_device_from_cdev_locked(struct ccw_device *cdev)
{
struct dasd_device *device = dev_get_drvdata(&cdev->dev);
if (!device)
return ERR_PTR(-ENODEV);
dasd_get_device(device);
return device;
}
/*
* Return dasd_device structure associated with cdev.
*/
struct dasd_device *
dasd_device_from_cdev(struct ccw_device *cdev)
{
struct dasd_device *device;
unsigned long flags;
spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
device = dasd_device_from_cdev_locked(cdev);
spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
return device;
}
/*
* SECTION: files in sysfs
*/
/*
* failfast controls the behaviour, if no path is available
*/
static ssize_t dasd_ff_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct dasd_devmap *devmap;
int ff_flag;
devmap = dasd_find_busid(dev->bus_id);
if (!IS_ERR(devmap))
ff_flag = (devmap->features & DASD_FEATURE_FAILFAST) != 0;
else
ff_flag = (DASD_FEATURE_DEFAULT & DASD_FEATURE_FAILFAST) != 0;
return snprintf(buf, PAGE_SIZE, ff_flag ? "1\n" : "0\n");
}
static ssize_t dasd_ff_store(struct device *dev, struct device_attribute *attr,
const char *buf, size_t count)
{
struct dasd_devmap *devmap;
int val;
char *endp;
devmap = dasd_devmap_from_cdev(to_ccwdev(dev));
if (IS_ERR(devmap))
return PTR_ERR(devmap);
val = simple_strtoul(buf, &endp, 0);
if (((endp + 1) < (buf + count)) || (val > 1))
return -EINVAL;
spin_lock(&dasd_devmap_lock);
if (val)
devmap->features |= DASD_FEATURE_FAILFAST;
else
devmap->features &= ~DASD_FEATURE_FAILFAST;
if (devmap->device)
devmap->device->features = devmap->features;
spin_unlock(&dasd_devmap_lock);
return count;
}
static DEVICE_ATTR(failfast, 0644, dasd_ff_show, dasd_ff_store);
/*
* readonly controls the readonly status of a dasd
*/
static ssize_t
dasd_ro_show(struct device *dev, struct device_attribute *attr, char *buf)
{
struct dasd_devmap *devmap;
int ro_flag;
devmap = dasd_find_busid(dev_name(dev));
if (!IS_ERR(devmap))
ro_flag = (devmap->features & DASD_FEATURE_READONLY) != 0;
else
ro_flag = (DASD_FEATURE_DEFAULT & DASD_FEATURE_READONLY) != 0;
return snprintf(buf, PAGE_SIZE, ro_flag ? "1\n" : "0\n");
}
static ssize_t
dasd_ro_store(struct device *dev, struct device_attribute *attr,
const char *buf, size_t count)
{
struct dasd_devmap *devmap;
int val;
char *endp;
devmap = dasd_devmap_from_cdev(to_ccwdev(dev));
if (IS_ERR(devmap))
return PTR_ERR(devmap);
val = simple_strtoul(buf, &endp, 0);
if (((endp + 1) < (buf + count)) || (val > 1))
return -EINVAL;
spin_lock(&dasd_devmap_lock);
if (val)
devmap->features |= DASD_FEATURE_READONLY;
else
devmap->features &= ~DASD_FEATURE_READONLY;
if (devmap->device)
devmap->device->features = devmap->features;
[S390] dasd: add hyper PAV support to DASD device driver, part 1 Parallel access volumes (PAV) is a storage server feature, that allows to start multiple channel programs on the same DASD in parallel. It defines alias devices which can be used as alternative paths to the same disk. With the old base PAV support we only needed rudimentary functionality in the DASD device driver. As the mapping between base and alias devices was static, we just had to export an identifier (uid) and could leave the combining of devices to external layers like a device mapper multipath. Now hyper PAV removes the requirement to dedicate alias devices to specific base devices. Instead each alias devices can be combined with multiple base device on a per request basis. This requires full support by the DASD device driver as now each channel program itself has to identify the target base device. The changes to the dasd device driver and the ECKD discipline are: - Separate subchannel device representation (dasd_device) from block device representation (dasd_block). Only base devices are block devices. - Gather information about base and alias devices and possible combinations. - For each request decide which dasd_device should be used (base or alias) and build specific channel program. - Support summary unit checks, which allow the storage server to upgrade / downgrade between base and hyper PAV at runtime (support is mandatory). Signed-off-by: Stefan Weinhuber <wein@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-01-26 06:11:23 -07:00
if (devmap->device && devmap->device->block
&& devmap->device->block->gdp)
set_disk_ro(devmap->device->block->gdp, val);
spin_unlock(&dasd_devmap_lock);
return count;
}
static DEVICE_ATTR(readonly, 0644, dasd_ro_show, dasd_ro_store);
/*
* erplog controls the logging of ERP related data
* (e.g. failing channel programs).
*/
static ssize_t
dasd_erplog_show(struct device *dev, struct device_attribute *attr, char *buf)
{
struct dasd_devmap *devmap;
int erplog;
devmap = dasd_find_busid(dev_name(dev));
if (!IS_ERR(devmap))
erplog = (devmap->features & DASD_FEATURE_ERPLOG) != 0;
else
erplog = (DASD_FEATURE_DEFAULT & DASD_FEATURE_ERPLOG) != 0;
return snprintf(buf, PAGE_SIZE, erplog ? "1\n" : "0\n");
}
static ssize_t
dasd_erplog_store(struct device *dev, struct device_attribute *attr,
const char *buf, size_t count)
{
struct dasd_devmap *devmap;
int val;
char *endp;
devmap = dasd_devmap_from_cdev(to_ccwdev(dev));
if (IS_ERR(devmap))
return PTR_ERR(devmap);
val = simple_strtoul(buf, &endp, 0);
if (((endp + 1) < (buf + count)) || (val > 1))
return -EINVAL;
spin_lock(&dasd_devmap_lock);
if (val)
devmap->features |= DASD_FEATURE_ERPLOG;
else
devmap->features &= ~DASD_FEATURE_ERPLOG;
if (devmap->device)
devmap->device->features = devmap->features;
spin_unlock(&dasd_devmap_lock);
return count;
}
static DEVICE_ATTR(erplog, 0644, dasd_erplog_show, dasd_erplog_store);
/*
* use_diag controls whether the driver should use diag rather than ssch
* to talk to the device
*/
static ssize_t
dasd_use_diag_show(struct device *dev, struct device_attribute *attr, char *buf)
{
struct dasd_devmap *devmap;
int use_diag;
devmap = dasd_find_busid(dev_name(dev));
if (!IS_ERR(devmap))
use_diag = (devmap->features & DASD_FEATURE_USEDIAG) != 0;
else
use_diag = (DASD_FEATURE_DEFAULT & DASD_FEATURE_USEDIAG) != 0;
return sprintf(buf, use_diag ? "1\n" : "0\n");
}
static ssize_t
dasd_use_diag_store(struct device *dev, struct device_attribute *attr,
const char *buf, size_t count)
{
struct dasd_devmap *devmap;
ssize_t rc;
int val;
char *endp;
devmap = dasd_devmap_from_cdev(to_ccwdev(dev));
if (IS_ERR(devmap))
return PTR_ERR(devmap);
val = simple_strtoul(buf, &endp, 0);
if (((endp + 1) < (buf + count)) || (val > 1))
return -EINVAL;
spin_lock(&dasd_devmap_lock);
/* Changing diag discipline flag is only allowed in offline state. */
rc = count;
if (!devmap->device) {
if (val)
devmap->features |= DASD_FEATURE_USEDIAG;
else
devmap->features &= ~DASD_FEATURE_USEDIAG;
} else
rc = -EPERM;
spin_unlock(&dasd_devmap_lock);
return rc;
}
static DEVICE_ATTR(use_diag, 0644, dasd_use_diag_show, dasd_use_diag_store);
static ssize_t
dasd_discipline_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct dasd_device *device;
ssize_t len;
device = dasd_device_from_cdev(to_ccwdev(dev));
if (!IS_ERR(device) && device->discipline) {
len = snprintf(buf, PAGE_SIZE, "%s\n",
device->discipline->name);
dasd_put_device(device);
} else
len = snprintf(buf, PAGE_SIZE, "none\n");
return len;
}
static DEVICE_ATTR(discipline, 0444, dasd_discipline_show, NULL);
static ssize_t
dasd_device_status_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct dasd_device *device;
ssize_t len;
device = dasd_device_from_cdev(to_ccwdev(dev));
if (!IS_ERR(device)) {
switch (device->state) {
case DASD_STATE_NEW:
len = snprintf(buf, PAGE_SIZE, "new\n");
break;
case DASD_STATE_KNOWN:
len = snprintf(buf, PAGE_SIZE, "detected\n");
break;
case DASD_STATE_BASIC:
len = snprintf(buf, PAGE_SIZE, "basic\n");
break;
case DASD_STATE_UNFMT:
len = snprintf(buf, PAGE_SIZE, "unformatted\n");
break;
case DASD_STATE_READY:
len = snprintf(buf, PAGE_SIZE, "ready\n");
break;
case DASD_STATE_ONLINE:
len = snprintf(buf, PAGE_SIZE, "online\n");
break;
default:
len = snprintf(buf, PAGE_SIZE, "no stat\n");
break;
}
dasd_put_device(device);
} else
len = snprintf(buf, PAGE_SIZE, "unknown\n");
return len;
}
static DEVICE_ATTR(status, 0444, dasd_device_status_show, NULL);
static ssize_t
dasd_alias_show(struct device *dev, struct device_attribute *attr, char *buf)
{
struct dasd_devmap *devmap;
int alias;
devmap = dasd_find_busid(dev_name(dev));
spin_lock(&dasd_devmap_lock);
[S390] dasd: add hyper PAV support to DASD device driver, part 1 Parallel access volumes (PAV) is a storage server feature, that allows to start multiple channel programs on the same DASD in parallel. It defines alias devices which can be used as alternative paths to the same disk. With the old base PAV support we only needed rudimentary functionality in the DASD device driver. As the mapping between base and alias devices was static, we just had to export an identifier (uid) and could leave the combining of devices to external layers like a device mapper multipath. Now hyper PAV removes the requirement to dedicate alias devices to specific base devices. Instead each alias devices can be combined with multiple base device on a per request basis. This requires full support by the DASD device driver as now each channel program itself has to identify the target base device. The changes to the dasd device driver and the ECKD discipline are: - Separate subchannel device representation (dasd_device) from block device representation (dasd_block). Only base devices are block devices. - Gather information about base and alias devices and possible combinations. - For each request decide which dasd_device should be used (base or alias) and build specific channel program. - Support summary unit checks, which allow the storage server to upgrade / downgrade between base and hyper PAV at runtime (support is mandatory). Signed-off-by: Stefan Weinhuber <wein@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-01-26 06:11:23 -07:00
if (IS_ERR(devmap) || strlen(devmap->uid.vendor) == 0) {
spin_unlock(&dasd_devmap_lock);
return sprintf(buf, "0\n");
}
if (devmap->uid.type == UA_BASE_PAV_ALIAS ||
devmap->uid.type == UA_HYPER_PAV_ALIAS)
alias = 1;
else
alias = 0;
spin_unlock(&dasd_devmap_lock);
return sprintf(buf, alias ? "1\n" : "0\n");
}
static DEVICE_ATTR(alias, 0444, dasd_alias_show, NULL);
static ssize_t
dasd_vendor_show(struct device *dev, struct device_attribute *attr, char *buf)
{
struct dasd_devmap *devmap;
char *vendor;
devmap = dasd_find_busid(dev_name(dev));
spin_lock(&dasd_devmap_lock);
if (!IS_ERR(devmap) && strlen(devmap->uid.vendor) > 0)
vendor = devmap->uid.vendor;
else
vendor = "";
spin_unlock(&dasd_devmap_lock);
return snprintf(buf, PAGE_SIZE, "%s\n", vendor);
}
static DEVICE_ATTR(vendor, 0444, dasd_vendor_show, NULL);
#define UID_STRLEN ( /* vendor */ 3 + 1 + /* serial */ 14 + 1 +\
/* SSID */ 4 + 1 + /* unit addr */ 2 + 1 +\
/* vduit */ 32 + 1)
static ssize_t
dasd_uid_show(struct device *dev, struct device_attribute *attr, char *buf)
{
struct dasd_devmap *devmap;
[S390] dasd: add hyper PAV support to DASD device driver, part 1 Parallel access volumes (PAV) is a storage server feature, that allows to start multiple channel programs on the same DASD in parallel. It defines alias devices which can be used as alternative paths to the same disk. With the old base PAV support we only needed rudimentary functionality in the DASD device driver. As the mapping between base and alias devices was static, we just had to export an identifier (uid) and could leave the combining of devices to external layers like a device mapper multipath. Now hyper PAV removes the requirement to dedicate alias devices to specific base devices. Instead each alias devices can be combined with multiple base device on a per request basis. This requires full support by the DASD device driver as now each channel program itself has to identify the target base device. The changes to the dasd device driver and the ECKD discipline are: - Separate subchannel device representation (dasd_device) from block device representation (dasd_block). Only base devices are block devices. - Gather information about base and alias devices and possible combinations. - For each request decide which dasd_device should be used (base or alias) and build specific channel program. - Support summary unit checks, which allow the storage server to upgrade / downgrade between base and hyper PAV at runtime (support is mandatory). Signed-off-by: Stefan Weinhuber <wein@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-01-26 06:11:23 -07:00
char uid_string[UID_STRLEN];
char ua_string[3];
struct dasd_uid *uid;
devmap = dasd_find_busid(dev_name(dev));
spin_lock(&dasd_devmap_lock);
[S390] dasd: add hyper PAV support to DASD device driver, part 1 Parallel access volumes (PAV) is a storage server feature, that allows to start multiple channel programs on the same DASD in parallel. It defines alias devices which can be used as alternative paths to the same disk. With the old base PAV support we only needed rudimentary functionality in the DASD device driver. As the mapping between base and alias devices was static, we just had to export an identifier (uid) and could leave the combining of devices to external layers like a device mapper multipath. Now hyper PAV removes the requirement to dedicate alias devices to specific base devices. Instead each alias devices can be combined with multiple base device on a per request basis. This requires full support by the DASD device driver as now each channel program itself has to identify the target base device. The changes to the dasd device driver and the ECKD discipline are: - Separate subchannel device representation (dasd_device) from block device representation (dasd_block). Only base devices are block devices. - Gather information about base and alias devices and possible combinations. - For each request decide which dasd_device should be used (base or alias) and build specific channel program. - Support summary unit checks, which allow the storage server to upgrade / downgrade between base and hyper PAV at runtime (support is mandatory). Signed-off-by: Stefan Weinhuber <wein@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-01-26 06:11:23 -07:00
if (IS_ERR(devmap) || strlen(devmap->uid.vendor) == 0) {
spin_unlock(&dasd_devmap_lock);
return sprintf(buf, "\n");
}
uid = &devmap->uid;
switch (uid->type) {
case UA_BASE_DEVICE:
sprintf(ua_string, "%02x", uid->real_unit_addr);
break;
case UA_BASE_PAV_ALIAS:
sprintf(ua_string, "%02x", uid->base_unit_addr);
break;
case UA_HYPER_PAV_ALIAS:
sprintf(ua_string, "xx");
break;
default:
/* should not happen, treat like base device */
sprintf(ua_string, "%02x", uid->real_unit_addr);
break;
}
if (strlen(uid->vduit) > 0)
snprintf(uid_string, sizeof(uid_string),
"%s.%s.%04x.%s.%s",
uid->vendor, uid->serial,
uid->ssid, ua_string,
uid->vduit);
else
snprintf(uid_string, sizeof(uid_string),
"%s.%s.%04x.%s",
uid->vendor, uid->serial,
uid->ssid, ua_string);
spin_unlock(&dasd_devmap_lock);
[S390] dasd: add hyper PAV support to DASD device driver, part 1 Parallel access volumes (PAV) is a storage server feature, that allows to start multiple channel programs on the same DASD in parallel. It defines alias devices which can be used as alternative paths to the same disk. With the old base PAV support we only needed rudimentary functionality in the DASD device driver. As the mapping between base and alias devices was static, we just had to export an identifier (uid) and could leave the combining of devices to external layers like a device mapper multipath. Now hyper PAV removes the requirement to dedicate alias devices to specific base devices. Instead each alias devices can be combined with multiple base device on a per request basis. This requires full support by the DASD device driver as now each channel program itself has to identify the target base device. The changes to the dasd device driver and the ECKD discipline are: - Separate subchannel device representation (dasd_device) from block device representation (dasd_block). Only base devices are block devices. - Gather information about base and alias devices and possible combinations. - For each request decide which dasd_device should be used (base or alias) and build specific channel program. - Support summary unit checks, which allow the storage server to upgrade / downgrade between base and hyper PAV at runtime (support is mandatory). Signed-off-by: Stefan Weinhuber <wein@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-01-26 06:11:23 -07:00
return snprintf(buf, PAGE_SIZE, "%s\n", uid_string);
}
static DEVICE_ATTR(uid, 0444, dasd_uid_show, NULL);
/*
* extended error-reporting
*/
static ssize_t
dasd_eer_show(struct device *dev, struct device_attribute *attr, char *buf)
{
struct dasd_devmap *devmap;
int eer_flag;
devmap = dasd_find_busid(dev_name(dev));
if (!IS_ERR(devmap) && devmap->device)
eer_flag = dasd_eer_enabled(devmap->device);
else
eer_flag = 0;
return snprintf(buf, PAGE_SIZE, eer_flag ? "1\n" : "0\n");
}
static ssize_t
dasd_eer_store(struct device *dev, struct device_attribute *attr,
const char *buf, size_t count)
{
struct dasd_devmap *devmap;
int val, rc;
char *endp;
devmap = dasd_devmap_from_cdev(to_ccwdev(dev));
if (IS_ERR(devmap))
return PTR_ERR(devmap);
if (!devmap->device)
return -ENODEV;
val = simple_strtoul(buf, &endp, 0);
if (((endp + 1) < (buf + count)) || (val > 1))
return -EINVAL;
if (val) {
rc = dasd_eer_enable(devmap->device);
if (rc)
return rc;
} else
dasd_eer_disable(devmap->device);
return count;
}
static DEVICE_ATTR(eer_enabled, 0644, dasd_eer_show, dasd_eer_store);
static struct attribute * dasd_attrs[] = {
&dev_attr_readonly.attr,
&dev_attr_discipline.attr,
&dev_attr_status.attr,
&dev_attr_alias.attr,
&dev_attr_vendor.attr,
&dev_attr_uid.attr,
&dev_attr_use_diag.attr,
&dev_attr_eer_enabled.attr,
&dev_attr_erplog.attr,
&dev_attr_failfast.attr,
NULL,
};
static struct attribute_group dasd_attr_group = {
.attrs = dasd_attrs,
};
/*
* Return copy of the device unique identifier.
*/
int
dasd_get_uid(struct ccw_device *cdev, struct dasd_uid *uid)
{
struct dasd_devmap *devmap;
devmap = dasd_find_busid(dev_name(&cdev->dev));
if (IS_ERR(devmap))
return PTR_ERR(devmap);
spin_lock(&dasd_devmap_lock);
*uid = devmap->uid;
spin_unlock(&dasd_devmap_lock);
return 0;
}
/*
* Register the given device unique identifier into devmap struct.
* In addition check if the related storage server subsystem ID is already
* contained in the dasd_server_ssid_list. If subsystem ID is not contained,
* create new entry.
* Return 0 if server was already in serverlist,
* 1 if the server was added successful
* <0 in case of error.
*/
int
dasd_set_uid(struct ccw_device *cdev, struct dasd_uid *uid)
{
struct dasd_devmap *devmap;
devmap = dasd_find_busid(dev_name(&cdev->dev));
if (IS_ERR(devmap))
return PTR_ERR(devmap);
spin_lock(&dasd_devmap_lock);
devmap->uid = *uid;
spin_unlock(&dasd_devmap_lock);
[S390] dasd: add hyper PAV support to DASD device driver, part 1 Parallel access volumes (PAV) is a storage server feature, that allows to start multiple channel programs on the same DASD in parallel. It defines alias devices which can be used as alternative paths to the same disk. With the old base PAV support we only needed rudimentary functionality in the DASD device driver. As the mapping between base and alias devices was static, we just had to export an identifier (uid) and could leave the combining of devices to external layers like a device mapper multipath. Now hyper PAV removes the requirement to dedicate alias devices to specific base devices. Instead each alias devices can be combined with multiple base device on a per request basis. This requires full support by the DASD device driver as now each channel program itself has to identify the target base device. The changes to the dasd device driver and the ECKD discipline are: - Separate subchannel device representation (dasd_device) from block device representation (dasd_block). Only base devices are block devices. - Gather information about base and alias devices and possible combinations. - For each request decide which dasd_device should be used (base or alias) and build specific channel program. - Support summary unit checks, which allow the storage server to upgrade / downgrade between base and hyper PAV at runtime (support is mandatory). Signed-off-by: Stefan Weinhuber <wein@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-01-26 06:11:23 -07:00
return 0;
}
EXPORT_SYMBOL_GPL(dasd_set_uid);
/*
* Return value of the specified feature.
*/
int
dasd_get_feature(struct ccw_device *cdev, int feature)
{
struct dasd_devmap *devmap;
devmap = dasd_find_busid(dev_name(&cdev->dev));
if (IS_ERR(devmap))
return PTR_ERR(devmap);
return ((devmap->features & feature) != 0);
}
/*
* Set / reset given feature.
* Flag indicates wether to set (!=0) or the reset (=0) the feature.
*/
int
dasd_set_feature(struct ccw_device *cdev, int feature, int flag)
{
struct dasd_devmap *devmap;
devmap = dasd_find_busid(dev_name(&cdev->dev));
if (IS_ERR(devmap))
return PTR_ERR(devmap);
spin_lock(&dasd_devmap_lock);
if (flag)
devmap->features |= feature;
else
devmap->features &= ~feature;
if (devmap->device)
devmap->device->features = devmap->features;
spin_unlock(&dasd_devmap_lock);
return 0;
}
int
dasd_add_sysfs_files(struct ccw_device *cdev)
{
return sysfs_create_group(&cdev->dev.kobj, &dasd_attr_group);
}
void
dasd_remove_sysfs_files(struct ccw_device *cdev)
{
sysfs_remove_group(&cdev->dev.kobj, &dasd_attr_group);
}
int
dasd_devmap_init(void)
{
int i;
/* Initialize devmap structures. */
dasd_max_devindex = 0;
for (i = 0; i < 256; i++)
INIT_LIST_HEAD(&dasd_hashlists[i]);
return 0;
}
void
dasd_devmap_exit(void)
{
dasd_forget_ranges();
}