Commit 20c64468 authored by Stefan Weinhuber's avatar Stefan Weinhuber Committed by Linus Torvalds

[PATCH] s390: dasd extended error reporting

The DASD extended error reporting is a facility that allows to get detailed
information about certain problems in the DASD I/O.  This information can be
used to implement fail-over applications that can recover these problems.
Signed-off-by: default avatarStefan Weinhuber <wein@de.ibm.com>
Signed-off-by: default avatarMartin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
parent 554a826e
......@@ -55,4 +55,12 @@ config DASD_DIAG
Disks under VM. If you are not running under VM or unsure what it is,
say "N".
config DASD_EER
bool "Extended error reporting (EER)"
depends on DASD
help
This driver provides a character device interface to the
DASD extended error reporting. This is only needed if you want to
use applications written for the EER facility.
endif
......@@ -7,6 +7,9 @@ dasd_fba_mod-objs := dasd_fba.o dasd_3370_erp.o dasd_9336_erp.o
dasd_diag_mod-objs := dasd_diag.o
dasd_mod-objs := dasd.o dasd_ioctl.o dasd_proc.o dasd_devmap.o \
dasd_genhd.o dasd_erp.o
ifdef CONFIG_DASD_EER
dasd_mod-objs += dasd_eer.o
endif
obj-$(CONFIG_DASD) += dasd_mod.o
obj-$(CONFIG_DASD_DIAG) += dasd_diag_mod.o
......
......@@ -151,6 +151,8 @@ dasd_state_new_to_known(struct dasd_device *device)
static inline void
dasd_state_known_to_new(struct dasd_device * device)
{
/* Disable extended error reporting for this device. */
dasd_eer_disable(device);
/* Forget the discipline information. */
if (device->discipline)
module_put(device->discipline->owner);
......@@ -892,6 +894,9 @@ dasd_handle_state_change_pending(struct dasd_device *device)
struct dasd_ccw_req *cqr;
struct list_head *l, *n;
/* First of all start sense subsystem status request. */
dasd_eer_snss(device);
device->stopped &= ~DASD_STOPPED_PENDING;
/* restart all 'running' IO on queue */
......@@ -1111,6 +1116,19 @@ __dasd_process_ccw_queue(struct dasd_device * device,
}
goto restart;
}
/* First of all call extended error reporting. */
if (dasd_eer_enabled(device) &&
cqr->status == DASD_CQR_FAILED) {
dasd_eer_write(device, cqr, DASD_EER_FATALERROR);
/* restart request */
cqr->status = DASD_CQR_QUEUED;
cqr->retries = 255;
device->stopped |= DASD_STOPPED_QUIESCE;
goto restart;
}
/* Process finished ERP request. */
if (cqr->refers) {
__dasd_process_erp(device, cqr);
......@@ -1248,7 +1266,8 @@ __dasd_start_head(struct dasd_device * device)
cqr = list_entry(device->ccw_queue.next, struct dasd_ccw_req, list);
/* check FAILFAST */
if (device->stopped & ~DASD_STOPPED_PENDING &&
test_bit(DASD_CQR_FLAGS_FAILFAST, &cqr->flags)) {
test_bit(DASD_CQR_FLAGS_FAILFAST, &cqr->flags) &&
(!dasd_eer_enabled(device))) {
cqr->status = DASD_CQR_FAILED;
dasd_schedule_bh(device);
}
......@@ -1807,6 +1826,7 @@ dasd_exit(void)
#ifdef CONFIG_PROC_FS
dasd_proc_exit();
#endif
dasd_eer_exit();
if (dasd_page_cache != NULL) {
kmem_cache_destroy(dasd_page_cache);
dasd_page_cache = NULL;
......@@ -2003,6 +2023,9 @@ dasd_generic_notify(struct ccw_device *cdev, int event)
switch (event) {
case CIO_GONE:
case CIO_NO_PATH:
/* First of all call extended error reporting. */
dasd_eer_write(device, NULL, DASD_EER_NOPATH);
if (device->state < DASD_STATE_BASIC)
break;
/* Device is active. We want to keep it. */
......@@ -2060,6 +2083,7 @@ dasd_generic_auto_online (struct ccw_driver *dasd_discipline_driver)
put_driver(drv);
}
static int __init
dasd_init(void)
{
......@@ -2092,6 +2116,9 @@ dasd_init(void)
rc = dasd_parse();
if (rc)
goto failed;
rc = dasd_eer_init();
if (rc)
goto failed;
#ifdef CONFIG_PROC_FS
rc = dasd_proc_init();
if (rc)
......
......@@ -1108,6 +1108,9 @@ dasd_3990_handle_env_data(struct dasd_ccw_req * erp, char *sense)
case 0x0B:
DEV_MESSAGE(KERN_WARNING, device, "%s",
"FORMAT F - Volume is suspended duplex");
/* call extended error reporting (EER) */
dasd_eer_write(device, erp->refers,
DASD_EER_PPRCSUSPEND);
break;
case 0x0C:
DEV_MESSAGE(KERN_WARNING, device, "%s",
......
......@@ -715,10 +715,51 @@ dasd_discipline_show(struct device *dev, struct device_attribute *attr, char *bu
static DEVICE_ATTR(discipline, 0444, dasd_discipline_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->bus_id);
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 rc;
devmap = dasd_devmap_from_cdev(to_ccwdev(dev));
if (IS_ERR(devmap))
return PTR_ERR(devmap);
if (!devmap->device)
return count;
if (buf[0] == '1') {
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_use_diag.attr,
&dev_attr_eer_enabled.attr,
NULL,
};
......
......@@ -29,6 +29,7 @@
#define DASD_ECKD_CCW_PSF 0x27
#define DASD_ECKD_CCW_RSSD 0x3e
#define DASD_ECKD_CCW_LOCATE_RECORD 0x47
#define DASD_ECKD_CCW_SNSS 0x54
#define DASD_ECKD_CCW_DEFINE_EXTENT 0x63
#define DASD_ECKD_CCW_WRITE_MT 0x85
#define DASD_ECKD_CCW_READ_MT 0x86
......
/*
* Character device driver for extended error reporting.
*
* Copyright (C) 2005 IBM Corporation
* extended error reporting for DASD ECKD devices
* Author(s): Stefan Weinhuber <wein@de.ibm.com>
*/
#include <linux/init.h>
#include <linux/fs.h>
#include <linux/kernel.h>
#include <linux/miscdevice.h>
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/device.h>
#include <linux/poll.h>
#include <asm/uaccess.h>
#include <asm/semaphore.h>
#include <asm/atomic.h>
#include <asm/ebcdic.h>
#include "dasd_int.h"
#include "dasd_eckd.h"
#ifdef PRINTK_HEADER
#undef PRINTK_HEADER
#endif /* PRINTK_HEADER */
#define PRINTK_HEADER "dasd(eer):"
/*
* SECTION: the internal buffer
*/
/*
* The internal buffer is meant to store obaque blobs of data, so it does
* not know of higher level concepts like triggers.
* It consists of a number of pages that are used as a ringbuffer. Each data
* blob is stored in a simple record that consists of an integer, which
* contains the size of the following data, and the data bytes themselfes.
*
* To allow for multiple independent readers we create one internal buffer
* each time the device is opened and destroy the buffer when the file is
* closed again. The number of pages used for this buffer is determined by
* the module parmeter eer_pages.
*
* One record can be written to a buffer by using the functions
* - dasd_eer_start_record (one time per record to write the size to the
* buffer and reserve the space for the data)
* - dasd_eer_write_buffer (one or more times per record to write the data)
* The data can be written in several steps but you will have to compute
* the total size up front for the invocation of dasd_eer_start_record.
* If the ringbuffer is full, dasd_eer_start_record will remove the required
* number of old records.
*
* A record is typically read in two steps, first read the integer that
* specifies the size of the following data, then read the data.
* Both can be done by
* - dasd_eer_read_buffer
*
* For all mentioned functions you need to get the bufferlock first and keep
* it until a complete record is written or read.
*
* All information necessary to keep track of an internal buffer is kept in
* a struct eerbuffer. The buffer specific to a file pointer is strored in
* the private_data field of that file. To be able to write data to all
* existing buffers, each buffer is also added to the bufferlist.
* If the user does not want to read a complete record in one go, we have to
* keep track of the rest of the record. residual stores the number of bytes
* that are still to deliver. If the rest of the record is invalidated between
* two reads then residual will be set to -1 so that the next read will fail.
* All entries in the eerbuffer structure are protected with the bufferlock.
* To avoid races between writing to a buffer on the one side and creating
* and destroying buffers on the other side, the bufferlock must also be used
* to protect the bufferlist.
*/
static int eer_pages = 5;
module_param(eer_pages, int, S_IRUGO|S_IWUSR);
struct eerbuffer {
struct list_head list;
char **buffer;
int buffersize;
int buffer_page_count;
int head;
int tail;
int residual;
};
static LIST_HEAD(bufferlist);
static spinlock_t bufferlock = SPIN_LOCK_UNLOCKED;
static DECLARE_WAIT_QUEUE_HEAD(dasd_eer_read_wait_queue);
/*
* How many free bytes are available on the buffer.
* Needs to be called with bufferlock held.
*/
static int dasd_eer_get_free_bytes(struct eerbuffer *eerb)
{
if (eerb->head < eerb->tail)
return eerb->tail - eerb->head - 1;
return eerb->buffersize - eerb->head + eerb->tail -1;
}
/*
* How many bytes of buffer space are used.
* Needs to be called with bufferlock held.
*/
static int dasd_eer_get_filled_bytes(struct eerbuffer *eerb)
{
if (eerb->head >= eerb->tail)
return eerb->head - eerb->tail;
return eerb->buffersize - eerb->tail + eerb->head;
}
/*
* The dasd_eer_write_buffer function just copies count bytes of data
* to the buffer. Make sure to call dasd_eer_start_record first, to
* make sure that enough free space is available.
* Needs to be called with bufferlock held.
*/
static void dasd_eer_write_buffer(struct eerbuffer *eerb,
char *data, int count)
{
unsigned long headindex,localhead;
unsigned long rest, len;
char *nextdata;
nextdata = data;
rest = count;
while (rest > 0) {
headindex = eerb->head / PAGE_SIZE;
localhead = eerb->head % PAGE_SIZE;
len = min(rest, PAGE_SIZE - localhead);
memcpy(eerb->buffer[headindex]+localhead, nextdata, len);
nextdata += len;
rest -= len;
eerb->head += len;
if (eerb->head == eerb->buffersize)
eerb->head = 0; /* wrap around */
BUG_ON(eerb->head > eerb->buffersize);
}
}
/*
* Needs to be called with bufferlock held.
*/
static int dasd_eer_read_buffer(struct eerbuffer *eerb, char *data, int count)
{
unsigned long tailindex,localtail;
unsigned long rest, len, finalcount;
char *nextdata;
finalcount = min(count, dasd_eer_get_filled_bytes(eerb));
nextdata = data;
rest = finalcount;
while (rest > 0) {
tailindex = eerb->tail / PAGE_SIZE;
localtail = eerb->tail % PAGE_SIZE;
len = min(rest, PAGE_SIZE - localtail);
memcpy(nextdata, eerb->buffer[tailindex] + localtail, len);
nextdata += len;
rest -= len;
eerb->tail += len;
if (eerb->tail == eerb->buffersize)
eerb->tail = 0; /* wrap around */
BUG_ON(eerb->tail > eerb->buffersize);
}
return finalcount;
}
/*
* Whenever you want to write a blob of data to the internal buffer you
* have to start by using this function first. It will write the number
* of bytes that will be written to the buffer. If necessary it will remove
* old records to make room for the new one.
* Needs to be called with bufferlock held.
*/
static int dasd_eer_start_record(struct eerbuffer *eerb, int count)
{
int tailcount;
if (count + sizeof(count) > eerb->buffersize)
return -ENOMEM;
while (dasd_eer_get_free_bytes(eerb) < count + sizeof(count)) {
if (eerb->residual > 0) {
eerb->tail += eerb->residual;
if (eerb->tail >= eerb->buffersize)
eerb->tail -= eerb->buffersize;
eerb->residual = -1;
}
dasd_eer_read_buffer(eerb, (char *) &tailcount,
sizeof(tailcount));
eerb->tail += tailcount;
if (eerb->tail >= eerb->buffersize)
eerb->tail -= eerb->buffersize;
}
dasd_eer_write_buffer(eerb, (char*) &count, sizeof(count));
return 0;
};
/*
* Release pages that are not used anymore.
*/
static void dasd_eer_free_buffer_pages(char **buf, int no_pages)
{
int i;
for (i = 0; i < no_pages; i++)
free_page((unsigned long) buf[i]);
}
/*
* Allocate a new set of memory pages.
*/
static int dasd_eer_allocate_buffer_pages(char **buf, int no_pages)
{
int i;
for (i = 0; i < no_pages; i++) {
buf[i] = (char *) get_zeroed_page(GFP_KERNEL);
if (!buf[i]) {
dasd_eer_free_buffer_pages(buf, i);
return -ENOMEM;
}
}
return 0;
}
/*
* SECTION: The extended error reporting functionality
*/
/*
* When a DASD device driver wants to report an error, it calls the
* function dasd_eer_write and gives the respective trigger ID as
* parameter. Currently there are four kinds of triggers:
*
* DASD_EER_FATALERROR: all kinds of unrecoverable I/O problems
* DASD_EER_PPRCSUSPEND: PPRC was suspended
* DASD_EER_NOPATH: There is no path to the device left.
* DASD_EER_STATECHANGE: The state of the device has changed.
*
* For the first three triggers all required information can be supplied by
* the caller. For these triggers a record is written by the function
* dasd_eer_write_standard_trigger.
*
* The DASD_EER_STATECHANGE trigger is special since a sense subsystem
* status ccw need to be executed to gather the necessary sense data first.
* The dasd_eer_snss function will queue the SNSS request and the request
* callback will then call dasd_eer_write with the DASD_EER_STATCHANGE
* trigger.
*
* To avoid memory allocations at runtime, the necessary memory is allocated
* when the extended error reporting is enabled for a device (by
* dasd_eer_probe). There is one sense subsystem status request for each
* eer enabled DASD device. The presence of the cqr in device->eer_cqr
* indicates that eer is enable for the device. The use of the snss request
* is protected by the DASD_FLAG_EER_IN_USE bit. When this flag indicates
* that the cqr is currently in use, dasd_eer_snss cannot start a second
* request but sets the DASD_FLAG_EER_SNSS flag instead. The callback of
* the SNSS request will check the bit and call dasd_eer_snss again.
*/
#define SNSS_DATA_SIZE 44
#define DASD_EER_BUSID_SIZE 10
struct dasd_eer_header {
__u32 total_size;
__u32 trigger;
__u64 tv_sec;
__u64 tv_usec;
char busid[DASD_EER_BUSID_SIZE];
};
/*
* The following function can be used for those triggers that have
* all necessary data available when the function is called.
* If the parameter cqr is not NULL, the chain of requests will be searched
* for valid sense data, and all valid sense data sets will be added to
* the triggers data.
*/
static void dasd_eer_write_standard_trigger(struct dasd_device *device,
struct dasd_ccw_req *cqr,
int trigger)
{
struct dasd_ccw_req *temp_cqr;
int data_size;
struct timeval tv;
struct dasd_eer_header header;
unsigned long flags;
struct eerbuffer *eerb;
/* go through cqr chain and count the valid sense data sets */
data_size = 0;
for (temp_cqr = cqr; temp_cqr; temp_cqr = temp_cqr->refers)
if (temp_cqr->irb.esw.esw0.erw.cons)
data_size += 32;
header.total_size = sizeof(header) + data_size + 4; /* "EOR" */
header.trigger = trigger;
do_gettimeofday(&tv);
header.tv_sec = tv.tv_sec;
header.tv_usec = tv.tv_usec;
strncpy(header.busid, device->cdev->dev.bus_id, DASD_EER_BUSID_SIZE);
spin_lock_irqsave(&bufferlock, flags);
list_for_each_entry(eerb, &bufferlist, list) {
dasd_eer_start_record(eerb, header.total_size);
dasd_eer_write_buffer(eerb, (char *) &header, sizeof(header));
for (temp_cqr = cqr; temp_cqr; temp_cqr = temp_cqr->refers)
if (temp_cqr->irb.esw.esw0.erw.cons)
dasd_eer_write_buffer(eerb, cqr->irb.ecw, 32);
dasd_eer_write_buffer(eerb, "EOR", 4);
}
spin_unlock_irqrestore(&bufferlock, flags);
wake_up_interruptible(&dasd_eer_read_wait_queue);
}
/*
* This function writes a DASD_EER_STATECHANGE trigger.
*/
static void dasd_eer_write_snss_trigger(struct dasd_device *device,
struct dasd_ccw_req *cqr,
int trigger)
{
int data_size;
int snss_rc;
struct timeval tv;
struct dasd_eer_header header;
unsigned long flags;
struct eerbuffer *eerb;
snss_rc = (cqr->status == DASD_CQR_FAILED) ? -EIO : 0;
if (snss_rc)
data_size = 0;
else
data_size = SNSS_DATA_SIZE;
header.total_size = sizeof(header) + data_size + 4; /* "EOR" */
header.trigger = DASD_EER_STATECHANGE;
do_gettimeofday(&tv);
header.tv_sec = tv.tv_sec;
header.tv_usec = tv.tv_usec;
strncpy(header.busid, device->cdev->dev.bus_id, DASD_EER_BUSID_SIZE);
spin_lock_irqsave(&bufferlock, flags);
list_for_each_entry(eerb, &bufferlist, list) {
dasd_eer_start_record(eerb, header.total_size);
dasd_eer_write_buffer(eerb, (char *) &header , sizeof(header));
if (!snss_rc)
dasd_eer_write_buffer(eerb, cqr->data, SNSS_DATA_SIZE);
dasd_eer_write_buffer(eerb, "EOR", 4);
}
spin_unlock_irqrestore(&bufferlock, flags);
wake_up_interruptible(&dasd_eer_read_wait_queue);
}
/*
* This function is called for all triggers. It calls the appropriate
* function that writes the actual trigger records.
*/
void dasd_eer_write(struct dasd_device *device, struct dasd_ccw_req *cqr,
unsigned int id)
{
if (!device->eer_cqr)
return;
switch (id) {
case DASD_EER_FATALERROR:
case DASD_EER_PPRCSUSPEND:
dasd_eer_write_standard_trigger(device, cqr, id);
break;
case DASD_EER_NOPATH:
dasd_eer_write_standard_trigger(device, NULL, id);
break;
case DASD_EER_STATECHANGE:
dasd_eer_write_snss_trigger(device, cqr, id);
break;
default: /* unknown trigger, so we write it without any sense data */
dasd_eer_write_standard_trigger(device, NULL, id);
break;
}
}
EXPORT_SYMBOL(dasd_eer_write);
/*
* Start a sense subsystem status request.
* Needs to be called with the device held.
*/
void dasd_eer_snss(struct dasd_device *device)
{
struct dasd_ccw_req *cqr;
cqr = device->eer_cqr;
if (!cqr) /* Device not eer enabled. */
return;
if (test_and_set_bit(DASD_FLAG_EER_IN_USE, &device->flags)) {
/* Sense subsystem status request in use. */
set_bit(DASD_FLAG_EER_SNSS, &device->flags);
return;
}
clear_bit(DASD_FLAG_EER_SNSS, &device->flags);
cqr->status = DASD_CQR_QUEUED;
list_add(&cqr->list, &device->ccw_queue);
dasd_schedule_bh(device);
}
/*
* Callback function for use with sense subsystem status request.
*/
static void dasd_eer_snss_cb(struct dasd_ccw_req *cqr, void *data)
{
struct dasd_device *device = cqr->device;
unsigned long flags;
dasd_eer_write(device, cqr, DASD_EER_STATECHANGE);
spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags);
if (device->eer_cqr == cqr) {
clear_bit(DASD_FLAG_EER_IN_USE, &device->flags);
if (test_bit(DASD_FLAG_EER_SNSS, &device->flags))
/* Another SNSS has been requested in the meantime. */
dasd_eer_snss(device);
cqr = NULL;
}
spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
if (cqr)
/*
* Extended error recovery has been switched off while
* the SNSS request was running. It could even have
* been switched off and on again in which case there
* is a new ccw in device->eer_cqr. Free the "old"
* snss request now.
*/
dasd_kfree_request(cqr, device);
}
/*
* Enable error reporting on a given device.
*/
int dasd_eer_enable(struct dasd_device *device)
{
struct dasd_ccw_req *cqr;
unsigned long flags;
if (device->eer_cqr)
return 0;
if (!device->discipline || strcmp(device->discipline->name, "ECKD"))
return -EPERM; /* FIXME: -EMEDIUMTYPE ? */
cqr = dasd_kmalloc_request("ECKD", 1 /* SNSS */,
SNSS_DATA_SIZE, device);
if (!cqr)
return -ENOMEM;
cqr->device = device;
cqr->retries = 255;
cqr->expires = 10 * HZ;
cqr->cpaddr->cmd_code = DASD_ECKD_CCW_SNSS;
cqr->cpaddr->count = SNSS_DATA_SIZE;
cqr->cpaddr->flags = 0;
cqr->cpaddr->cda = (__u32)(addr_t) cqr->data;
cqr->buildclk = get_clock();
cqr->status = DASD_CQR_FILLED;
cqr->callback = dasd_eer_snss_cb;
spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags);
if (!device->eer_cqr) {
device->eer_cqr = cqr;
cqr = NULL;
}
spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
if (cqr)
dasd_kfree_request(cqr, device);
return 0;
}
/*
* Disable error reporting on a given device.
*/
void dasd_eer_disable(struct dasd_device *device)
{
struct dasd_ccw_req *cqr;
unsigned long flags;
int in_use;
if (!device->eer_cqr)
return;
spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags);
cqr = device->eer_cqr;
device->eer_cqr = NULL;
clear_bit(DASD_FLAG_EER_SNSS, &device->flags);
in_use = test_and_clear_bit(DASD_FLAG_EER_IN_USE, &device->flags);
spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
if (cqr && !in_use)
dasd_kfree_request(cqr, device);
}
/*
* SECTION: the device operations
*/
/*
* On the one side we need a lock to access our internal buffer, on the
* other side a copy_to_user can sleep. So we need to copy the data we have
* to transfer in a readbuffer, which is protected by the readbuffer_mutex.
*/
static char readbuffer[PAGE_SIZE];
static DECLARE_MUTEX(readbuffer_mutex);
static int dasd_eer_open(struct inode *inp, struct file *filp)
{
struct eerbuffer *eerb;
unsigned long flags;
eerb = kzalloc(sizeof(struct eerbuffer), GFP_KERNEL);
eerb->buffer_page_count = eer_pages;
if (eerb->buffer_page_count < 1 ||
eerb->buffer_page_count > INT_MAX / PAGE_SIZE) {
kfree(eerb);
MESSAGE(KERN_WARNING, "can't open device since module "
"parameter eer_pages is smaller then 1 or"
" bigger then %d", (int)(INT_MAX / PAGE_SIZE));
return -EINVAL;
}
eerb->buffersize = eerb->buffer_page_count * PAGE_SIZE;
eerb->buffer = kmalloc(eerb->buffer_page_count * sizeof(char *),
GFP_KERNEL);
if (!eerb->buffer) {
kfree(eerb);
return -ENOMEM;
}
if (dasd_eer_allocate_buffer_pages(eerb->buffer,
eerb->buffer_page_count)) {
kfree(eerb->buffer);
kfree(eerb);
return -ENOMEM;
}
filp->private_data = eerb;
spin_lock_irqsave(&bufferlock, flags);
list_add(&eerb->list, &bufferlist);
spin_unlock_irqrestore(&bufferlock, flags);
return nonseekable_open(inp,filp);
}
static int dasd_eer_close(struct inode *inp, struct file *filp)
{
struct eerbuffer *eerb;
unsigned long flags;
eerb = (struct eerbuffer *) filp->private_data;
spin_lock_irqsave(&bufferlock, flags);
list_del(&eerb->list);
spin_unlock_irqrestore(&bufferlock, flags);
dasd_eer_free_buffer_pages(eerb->buffer, eerb->buffer_page_count);
kfree(eerb->buffer);
kfree(eerb);
return 0;
}
static ssize_t dasd_eer_read(struct file *filp, char __user *buf,
size_t count, loff_t *ppos)
{
int tc,rc;
int tailcount,effective_count;
unsigned long flags;
struct eerbuffer *eerb;
eerb = (struct eerbuffer *) filp->private_data;
if (down_interruptible(&readbuffer_mutex))
return -ERESTARTSYS;
spin_lock_irqsave(&bufferlock, flags);
if (eerb->residual < 0) { /* the remainder of this record */
/* has been deleted */
eerb->residual = 0;
spin_unlock_irqrestore(&bufferlock, flags);
up(&readbuffer_mutex);
return -EIO;
} else if (eerb->residual > 0) {
/* OK we still have a second half of a record to deliver */
effective_count = min(eerb->residual, (int) count);
eerb->residual -= effective_count;
} else {
tc = 0;
while (!tc) {
tc = dasd_eer_read_buffer(eerb, (char *) &tailcount,
sizeof(tailcount));
if (!tc) {
/* no data available */
spin_unlock_irqrestore(&bufferlock, flags);
up(&readbuffer_mutex);
if (filp->f_flags & O_NONBLOCK)
return -EAGAIN;
rc = wait_event_interruptible(
dasd_eer_read_wait_queue,
eerb->head != eerb->tail);
if (rc)
return rc;
if (down_interruptible(&readbuffer_mutex))
return -ERESTARTSYS;
spin_lock_irqsave(&bufferlock, flags);
}
}
WARN_ON(tc != sizeof(tailcount));
effective_count = min(tailcount,(int)count);
eerb->residual = tailcount - effective_count;
}
tc = dasd_eer_read_buffer(eerb, readbuffer, effective_count);
WARN_ON(tc != effective_count);
spin_unlock_irqrestore(&bufferlock, flags);
if (copy_to_user(buf, readbuffer, effective_count)) {
up(&readbuffer_mutex);
return -EFAULT;
}
up(&readbuffer_mutex);
return effective_count;
}
static unsigned int dasd_eer_poll(struct file *filp, poll_table *ptable)
{
unsigned int mask;
unsigned long flags;
struct eerbuffer *eerb;
eerb = (struct eerbuffer *) filp->private_data;
poll_wait(filp, &dasd_eer_read_wait_queue, ptable);
spin_lock_irqsave(&bufferlock, flags);
if (eerb->head != eerb->tail)
mask = POLLIN | POLLRDNORM ;
else
mask = 0;
spin_unlock_irqrestore(&bufferlock, flags);
return mask;
}
static struct file_operations dasd_eer_fops = {
.open = &dasd_eer_open,
.release = &dasd_eer_close,
.read = &dasd_eer_read,
.poll = &dasd_eer_poll,
.owner = THIS_MODULE,
};
static struct miscdevice dasd_eer_dev = {
.minor = MISC_DYNAMIC_MINOR,
.name = "dasd_eer",
.fops = &dasd_eer_fops,
};
int __init dasd_eer_init(void)
{
int rc;
rc = misc_register(&dasd_eer_dev);
if (rc) {
MESSAGE(KERN_ERR, "%s", "dasd_eer_init could not "
"register misc device");
return rc;
}
return 0;
}
void __exit dasd_eer_exit(void)
{
WARN_ON(misc_deregister(&dasd_eer_dev) != 0);
}
......@@ -268,6 +268,23 @@ struct dasd_discipline {
extern struct dasd_discipline *dasd_diag_discipline_pointer;
/*
* Notification numbers for extended error reporting notifications:
* The DASD_EER_DISABLE notification is sent before a dasd_device (and it's
* eer pointer) is freed. The error reporting module needs to do all necessary
* cleanup steps.
* The DASD_EER_TRIGGER notification sends the actual error reports (triggers).
*/
#define DASD_EER_DISABLE 0
#define DASD_EER_TRIGGER 1
/* Trigger IDs for extended error reporting DASD_EER_TRIGGER notification */
#define DASD_EER_FATALERROR 1
#define DASD_EER_NOPATH 2
#define DASD_EER_STATECHANGE 3
#define DASD_EER_PPRCSUSPEND 4
struct dasd_device {
/* Block device stuff. */
struct gendisk *gdp;
......@@ -281,6 +298,9 @@ struct dasd_device {
unsigned long flags; /* per device flags */
unsigned short features; /* copy of devmap-features (read-only!) */
/* extended error reporting stuff (eer) */
struct dasd_ccw_req *eer_cqr;
/* Device discipline stuff. */
struct dasd_discipline *discipline;
struct dasd_discipline *base_discipline;
......@@ -326,6 +346,8 @@ struct dasd_device {
/* per device flags */
#define DASD_FLAG_DSC_ERROR 2 /* return -EIO when disconnected */
#define DASD_FLAG_OFFLINE 3 /* device is in offline processing */
#define DASD_FLAG_EER_SNSS 4 /* A SNSS is required */
#define DASD_FLAG_EER_IN_USE 5 /* A SNSS request is running */
void dasd_put_device_wake(struct dasd_device *);
......@@ -545,6 +567,30 @@ dasd_era_t dasd_9336_erp_examine(struct dasd_ccw_req *, struct irb *);
dasd_era_t dasd_9343_erp_examine(struct dasd_ccw_req *, struct irb *);
struct dasd_ccw_req *dasd_9343_erp_action(struct dasd_ccw_req *);
/* externals in dasd_eer.c */
#ifdef CONFIG_DASD_EER
int dasd_eer_init(void);
void dasd_eer_exit(void);
int dasd_eer_enable(struct dasd_device *);
void dasd_eer_disable(struct dasd_device *);
void dasd_eer_write(struct dasd_device *, struct dasd_ccw_req *cqr,
unsigned int id);
void dasd_eer_snss(struct dasd_device *);
static inline int dasd_eer_enabled(struct dasd_device *device)
{
return device->eer_cqr != NULL;
}
#else
#define dasd_eer_init() (0)
#define dasd_eer_exit() do { } while (0)
#define dasd_eer_enable(d) (0)
#define dasd_eer_disable(d) do { } while (0)
#define dasd_eer_write(d,c,i) do { } while (0)
#define dasd_eer_snss(d) do { } while (0)
#define dasd_eer_enabled(d) (0)
#endif /* CONFIG_DASD_ERR */
#endif /* __KERNEL__ */
#endif /* DASD_H */
......
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