blob: 5e9ebdb0594c537e75fb07b965b7940b6fbc5aab [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0
/*
* 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>
* Copyright IBM Corp. 1999, 2009
*/
#define KMSG_COMPONENT "dasd"
#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
#include <linux/kmod.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/ctype.h>
#include <linux/major.h>
#include <linux/slab.h>
#include <linux/hdreg.h>
#include <linux/async.h>
#include <linux/mutex.h>
#include <linux/debugfs.h>
#include <linux/seq_file.h>
#include <linux/vmalloc.h>
#include <asm/ccwdev.h>
#include <asm/ebcdic.h>
#include <asm/idals.h>
#include <asm/itcw.h>
#include <asm/diag.h>
/* This is ugly... */
#define PRINTK_HEADER "dasd:"
#include "dasd_int.h"
/*
* SECTION: Constant definitions to be used within this file
*/
#define DASD_CHANQ_MAX_SIZE 4
#define DASD_DIAG_MOD "dasd_diag_mod"
static unsigned int queue_depth = 32;
static unsigned int nr_hw_queues = 4;
module_param(queue_depth, uint, 0444);
MODULE_PARM_DESC(queue_depth, "Default queue depth for new DASD devices");
module_param(nr_hw_queues, uint, 0444);
MODULE_PARM_DESC(nr_hw_queues, "Default number of hardware queues for new DASD devices");
/*
* SECTION: exported variables of dasd.c
*/
debug_info_t *dasd_debug_area;
EXPORT_SYMBOL(dasd_debug_area);
static struct dentry *dasd_debugfs_root_entry;
struct dasd_discipline *dasd_diag_discipline_pointer;
EXPORT_SYMBOL(dasd_diag_discipline_pointer);
void dasd_int_handler(struct ccw_device *, unsigned long, struct irb *);
MODULE_AUTHOR("Holger Smolinski <Holger.Smolinski@de.ibm.com>");
MODULE_DESCRIPTION("Linux on S/390 DASD device driver,"
" Copyright IBM Corp. 2000");
MODULE_SUPPORTED_DEVICE("dasd");
MODULE_LICENSE("GPL");
/*
* SECTION: prototypes for static functions of dasd.c
*/
static int dasd_alloc_queue(struct dasd_block *);
static void dasd_setup_queue(struct dasd_block *);
static void dasd_free_queue(struct dasd_block *);
static int dasd_flush_block_queue(struct dasd_block *);
static void dasd_device_tasklet(unsigned long);
static void dasd_block_tasklet(unsigned long);
static void do_kick_device(struct work_struct *);
static void do_restore_device(struct work_struct *);
static void do_reload_device(struct work_struct *);
static void do_requeue_requests(struct work_struct *);
static void dasd_return_cqr_cb(struct dasd_ccw_req *, void *);
static void dasd_device_timeout(struct timer_list *);
static void dasd_block_timeout(struct timer_list *);
static void __dasd_process_erp(struct dasd_device *, struct dasd_ccw_req *);
static void dasd_profile_init(struct dasd_profile *, struct dentry *);
static void dasd_profile_exit(struct dasd_profile *);
static void dasd_hosts_init(struct dentry *, struct dasd_device *);
static void dasd_hosts_exit(struct dasd_device *);
/*
* SECTION: Operations on the device structure.
*/
static wait_queue_head_t dasd_init_waitq;
static wait_queue_head_t dasd_flush_wq;
static wait_queue_head_t generic_waitq;
static wait_queue_head_t shutdown_waitq;
/*
* Allocate memory for a new device structure.
*/
struct dasd_device *dasd_alloc_device(void)
{
struct dasd_device *device;
device = kzalloc(sizeof(struct dasd_device), GFP_ATOMIC);
if (!device)
return ERR_PTR(-ENOMEM);
/* Get two pages for normal block device operations. */
device->ccw_mem = (void *) __get_free_pages(GFP_ATOMIC | GFP_DMA, 1);
if (!device->ccw_mem) {
kfree(device);
return ERR_PTR(-ENOMEM);
}
/* Get one page for error recovery. */
device->erp_mem = (void *) get_zeroed_page(GFP_ATOMIC | GFP_DMA);
if (!device->erp_mem) {
free_pages((unsigned long) device->ccw_mem, 1);
kfree(device);
return ERR_PTR(-ENOMEM);
}
dasd_init_chunklist(&device->ccw_chunks, device->ccw_mem, PAGE_SIZE*2);
dasd_init_chunklist(&device->erp_chunks, device->erp_mem, PAGE_SIZE);
spin_lock_init(&device->mem_lock);
atomic_set(&device->tasklet_scheduled, 0);
tasklet_init(&device->tasklet, dasd_device_tasklet,
(unsigned long) device);
INIT_LIST_HEAD(&device->ccw_queue);
timer_setup(&device->timer, dasd_device_timeout, 0);
INIT_WORK(&device->kick_work, do_kick_device);
INIT_WORK(&device->restore_device, do_restore_device);
INIT_WORK(&device->reload_device, do_reload_device);
INIT_WORK(&device->requeue_requests, do_requeue_requests);
device->state = DASD_STATE_NEW;
device->target = DASD_STATE_NEW;
mutex_init(&device->state_mutex);
spin_lock_init(&device->profile.lock);
return device;
}
/*
* Free memory of a device structure.
*/
void dasd_free_device(struct dasd_device *device)
{
kfree(device->private);
free_page((unsigned long) device->erp_mem);
free_pages((unsigned long) device->ccw_mem, 1);
kfree(device);
}
/*
* Allocate memory for a new device structure.
*/
struct dasd_block *dasd_alloc_block(void)
{
struct dasd_block *block;
block = kzalloc(sizeof(*block), GFP_ATOMIC);
if (!block)
return ERR_PTR(-ENOMEM);
/* open_count = 0 means device online but not in use */
atomic_set(&block->open_count, -1);
atomic_set(&block->tasklet_scheduled, 0);
tasklet_init(&block->tasklet, dasd_block_tasklet,
(unsigned long) block);
INIT_LIST_HEAD(&block->ccw_queue);
spin_lock_init(&block->queue_lock);
timer_setup(&block->timer, dasd_block_timeout, 0);
spin_lock_init(&block->profile.lock);
return block;
}
EXPORT_SYMBOL_GPL(dasd_alloc_block);
/*
* Free memory of a device structure.
*/
void dasd_free_block(struct dasd_block *block)
{
kfree(block);
}
EXPORT_SYMBOL_GPL(dasd_free_block);
/*
* Make a new device known to the system.
*/
static int dasd_state_new_to_known(struct dasd_device *device)
{
int rc;
/*
* As long as the device is not in state DASD_STATE_NEW we want to
* keep the reference count > 0.
*/
dasd_get_device(device);
if (device->block) {
rc = dasd_alloc_queue(device->block);
if (rc) {
dasd_put_device(device);
return rc;
}
}
device->state = DASD_STATE_KNOWN;
return 0;
}
/*
* Let the system forget about a device.
*/
static int dasd_state_known_to_new(struct dasd_device *device)
{
/* Disable extended error reporting for this device. */
dasd_eer_disable(device);
device->state = DASD_STATE_NEW;
if (device->block)
dasd_free_queue(device->block);
/* Give up reference we took in dasd_state_new_to_known. */
dasd_put_device(device);
return 0;
}
static struct dentry *dasd_debugfs_setup(const char *name,
struct dentry *base_dentry)
{
struct dentry *pde;
if (!base_dentry)
return NULL;
pde = debugfs_create_dir(name, base_dentry);
if (!pde || IS_ERR(pde))
return NULL;
return pde;
}
/*
* Request the irq line for the device.
*/
static int dasd_state_known_to_basic(struct dasd_device *device)
{
struct dasd_block *block = device->block;
int rc = 0;
/* Allocate and register gendisk structure. */
if (block) {
rc = dasd_gendisk_alloc(block);
if (rc)
return rc;
block->debugfs_dentry =
dasd_debugfs_setup(block->gdp->disk_name,
dasd_debugfs_root_entry);
dasd_profile_init(&block->profile, block->debugfs_dentry);
if (dasd_global_profile_level == DASD_PROFILE_ON)
dasd_profile_on(&device->block->profile);
}
device->debugfs_dentry =
dasd_debugfs_setup(dev_name(&device->cdev->dev),
dasd_debugfs_root_entry);
dasd_profile_init(&device->profile, device->debugfs_dentry);
dasd_hosts_init(device->debugfs_dentry, device);
/* register 'device' debug area, used for all DBF_DEV_XXX calls */
device->debug_area = debug_register(dev_name(&device->cdev->dev), 4, 1,
8 * sizeof(long));
debug_register_view(device->debug_area, &debug_sprintf_view);
debug_set_level(device->debug_area, DBF_WARNING);
DBF_DEV_EVENT(DBF_EMERG, device, "%s", "debug area created");
device->state = DASD_STATE_BASIC;
return rc;
}
/*
* Release the irq line for the device. Terminate any running i/o.
*/
static int dasd_state_basic_to_known(struct dasd_device *device)
{
int rc;
if (device->discipline->basic_to_known) {
rc = device->discipline->basic_to_known(device);
if (rc)
return rc;
}
if (device->block) {
dasd_profile_exit(&device->block->profile);
debugfs_remove(device->block->debugfs_dentry);
dasd_gendisk_free(device->block);
dasd_block_clear_timer(device->block);
}
rc = dasd_flush_device_queue(device);
if (rc)
return rc;
dasd_device_clear_timer(device);
dasd_profile_exit(&device->profile);
dasd_hosts_exit(device);
debugfs_remove(device->debugfs_dentry);
DBF_DEV_EVENT(DBF_EMERG, device, "%p debug area deleted", device);
if (device->debug_area != NULL) {
debug_unregister(device->debug_area);
device->debug_area = NULL;
}
device->state = DASD_STATE_KNOWN;
return 0;
}
/*
* Do the initial analysis. The do_analysis function may return
* -EAGAIN in which case the device keeps the state DASD_STATE_BASIC
* until the discipline decides to continue the startup sequence
* by calling the function dasd_change_state. The eckd disciplines
* uses this to start a ccw that detects the format. The completion
* interrupt for this detection ccw uses the kernel event daemon to
* trigger the call to dasd_change_state. All this is done in the
* discipline code, see dasd_eckd.c.
* After the analysis ccw is done (do_analysis returned 0) the block
* device is setup.
* In case the analysis returns an error, the device setup is stopped
* (a fake disk was already added to allow formatting).
*/
static int dasd_state_basic_to_ready(struct dasd_device *device)
{
int rc;
struct dasd_block *block;
struct gendisk *disk;
rc = 0;
block = device->block;
/* make disk known with correct capacity */
if (block) {
if (block->base->discipline->do_analysis != NULL)
rc = block->base->discipline->do_analysis(block);
if (rc) {
if (rc != -EAGAIN) {
device->state = DASD_STATE_UNFMT;
disk = device->block->gdp;
kobject_uevent(&disk_to_dev(disk)->kobj,
KOBJ_CHANGE);
goto out;
}
return rc;
}
dasd_setup_queue(block);
set_capacity(block->gdp,
block->blocks << block->s2b_shift);
device->state = DASD_STATE_READY;
rc = dasd_scan_partitions(block);
if (rc) {
device->state = DASD_STATE_BASIC;
return rc;
}
} else {
device->state = DASD_STATE_READY;
}
out:
if (device->discipline->basic_to_ready)
rc = device->discipline->basic_to_ready(device);
return rc;
}
static inline
int _wait_for_empty_queues(struct dasd_device *device)
{
if (device->block)
return list_empty(&device->ccw_queue) &&
list_empty(&device->block->ccw_queue);
else
return list_empty(&device->ccw_queue);
}
/*
* Remove device from block device layer. Destroy dirty buffers.
* Forget format information. Check if the target level is basic
* and if it is create fake disk for formatting.
*/
static int dasd_state_ready_to_basic(struct dasd_device *device)
{
int rc;
device->state = DASD_STATE_BASIC;
if (device->block) {
struct dasd_block *block = device->block;
rc = dasd_flush_block_queue(block);
if (rc) {
device->state = DASD_STATE_READY;
return rc;
}
dasd_destroy_partitions(block);
block->blocks = 0;
block->bp_block = 0;
block->s2b_shift = 0;
}
return 0;
}
/*
* Back to basic.
*/
static int dasd_state_unfmt_to_basic(struct dasd_device *device)
{
device->state = DASD_STATE_BASIC;
return 0;
}
/*
* Make the device online and schedule the bottom half to start
* the requeueing of requests from the linux request queue to the
* ccw queue.
*/
static int
dasd_state_ready_to_online(struct dasd_device * device)
{
struct gendisk *disk;
struct disk_part_iter piter;
struct hd_struct *part;
device->state = DASD_STATE_ONLINE;
if (device->block) {
dasd_schedule_block_bh(device->block);
if ((device->features & DASD_FEATURE_USERAW)) {
disk = device->block->gdp;
kobject_uevent(&disk_to_dev(disk)->kobj, KOBJ_CHANGE);
return 0;
}
disk = device->block->bdev->bd_disk;
disk_part_iter_init(&piter, disk, DISK_PITER_INCL_PART0);
while ((part = disk_part_iter_next(&piter)))
kobject_uevent(&part_to_dev(part)->kobj, KOBJ_CHANGE);
disk_part_iter_exit(&piter);
}
return 0;
}
/*
* Stop the requeueing of requests again.
*/
static int dasd_state_online_to_ready(struct dasd_device *device)
{
int rc;
struct gendisk *disk;
struct disk_part_iter piter;
struct hd_struct *part;
if (device->discipline->online_to_ready) {
rc = device->discipline->online_to_ready(device);
if (rc)
return rc;
}
device->state = DASD_STATE_READY;
if (device->block && !(device->features & DASD_FEATURE_USERAW)) {
disk = device->block->bdev->bd_disk;
disk_part_iter_init(&piter, disk, DISK_PITER_INCL_PART0);
while ((part = disk_part_iter_next(&piter)))
kobject_uevent(&part_to_dev(part)->kobj, KOBJ_CHANGE);
disk_part_iter_exit(&piter);
}
return 0;
}
/*
* Device startup state changes.
*/
static int dasd_increase_state(struct dasd_device *device)
{
int rc;
rc = 0;
if (device->state == DASD_STATE_NEW &&
device->target >= DASD_STATE_KNOWN)
rc = dasd_state_new_to_known(device);
if (!rc &&
device->state == DASD_STATE_KNOWN &&
device->target >= DASD_STATE_BASIC)
rc = dasd_state_known_to_basic(device);
if (!rc &&
device->state == DASD_STATE_BASIC &&
device->target >= DASD_STATE_READY)
rc = dasd_state_basic_to_ready(device);
if (!rc &&
device->state == DASD_STATE_UNFMT &&
device->target > DASD_STATE_UNFMT)
rc = -EPERM;
if (!rc &&
device->state == DASD_STATE_READY &&
device->target >= DASD_STATE_ONLINE)
rc = dasd_state_ready_to_online(device);
return rc;
}
/*
* Device shutdown state changes.
*/
static int dasd_decrease_state(struct dasd_device *device)
{
int rc;
rc = 0;
if (device->state == DASD_STATE_ONLINE &&
device->target <= DASD_STATE_READY)
rc = dasd_state_online_to_ready(device);
if (!rc &&
device->state == DASD_STATE_READY &&
device->target <= DASD_STATE_BASIC)
rc = dasd_state_ready_to_basic(device);
if (!rc &&
device->state == DASD_STATE_UNFMT &&
device->target <= DASD_STATE_BASIC)
rc = dasd_state_unfmt_to_basic(device);
if (!rc &&
device->state == DASD_STATE_BASIC &&
device->target <= DASD_STATE_KNOWN)
rc = dasd_state_basic_to_known(device);
if (!rc &&
device->state == DASD_STATE_KNOWN &&
device->target <= DASD_STATE_NEW)
rc = dasd_state_known_to_new(device);
return rc;
}
/*
* This is the main startup/shutdown routine.
*/
static void dasd_change_state(struct dasd_device *device)
{
int rc;
if (device->state == device->target)
/* Already where we want to go today... */
return;
if (device->state < device->target)
rc = dasd_increase_state(device);
else
rc = dasd_decrease_state(device);
if (rc == -EAGAIN)
return;
if (rc)
device->target = device->state;
/* let user-space know that the device status changed */
kobject_uevent(&device->cdev->dev.kobj, KOBJ_CHANGE);
if (device->state == device->target)
wake_up(&dasd_init_waitq);
}
/*
* Kick starter for devices that did not complete the startup/shutdown
* procedure or were sleeping because of a pending state.
* dasd_kick_device will schedule a call do do_kick_device to the kernel
* event daemon.
*/
static void do_kick_device(struct work_struct *work)
{
struct dasd_device *device = container_of(work, struct dasd_device, kick_work);
mutex_lock(&device->state_mutex);
dasd_change_state(device);
mutex_unlock(&device->state_mutex);
dasd_schedule_device_bh(device);
dasd_put_device(device);
}
void dasd_kick_device(struct dasd_device *device)
{
dasd_get_device(device);
/* queue call to dasd_kick_device to the kernel event daemon. */
if (!schedule_work(&device->kick_work))
dasd_put_device(device);
}
EXPORT_SYMBOL(dasd_kick_device);
/*
* dasd_reload_device will schedule a call do do_reload_device to the kernel
* event daemon.
*/
static void do_reload_device(struct work_struct *work)
{
struct dasd_device *device = container_of(work, struct dasd_device,
reload_device);
device->discipline->reload(device);
dasd_put_device(device);
}
void dasd_reload_device(struct dasd_device *device)
{
dasd_get_device(device);
/* queue call to dasd_reload_device to the kernel event daemon. */
if (!schedule_work(&device->reload_device))
dasd_put_device(device);
}
EXPORT_SYMBOL(dasd_reload_device);
/*
* dasd_restore_device will schedule a call do do_restore_device to the kernel
* event daemon.
*/
static void do_restore_device(struct work_struct *work)
{
struct dasd_device *device = container_of(work, struct dasd_device,
restore_device);
device->cdev->drv->restore(device->cdev);
dasd_put_device(device);
}
void dasd_restore_device(struct dasd_device *device)
{
dasd_get_device(device);
/* queue call to dasd_restore_device to the kernel event daemon. */
if (!schedule_work(&device->restore_device))
dasd_put_device(device);
}
/*
* Set the target state for a device and starts the state change.
*/
void dasd_set_target_state(struct dasd_device *device, int target)
{
dasd_get_device(device);
mutex_lock(&device->state_mutex);
/* If we are in probeonly mode stop at DASD_STATE_READY. */
if (dasd_probeonly && target > DASD_STATE_READY)
target = DASD_STATE_READY;
if (device->target != target) {
if (device->state == target)
wake_up(&dasd_init_waitq);
device->target = target;
}
if (device->state != device->target)
dasd_change_state(device);
mutex_unlock(&device->state_mutex);
dasd_put_device(device);
}
EXPORT_SYMBOL(dasd_set_target_state);
/*
* Enable devices with device numbers in [from..to].
*/
static inline int _wait_for_device(struct dasd_device *device)
{
return (device->state == device->target);
}
void dasd_enable_device(struct dasd_device *device)
{
dasd_set_target_state(device, DASD_STATE_ONLINE);
if (device->state <= DASD_STATE_KNOWN)
/* No discipline for device found. */
dasd_set_target_state(device, DASD_STATE_NEW);
/* Now wait for the devices to come up. */
wait_event(dasd_init_waitq, _wait_for_device(device));
dasd_reload_device(device);
if (device->discipline->kick_validate)
device->discipline->kick_validate(device);
}
EXPORT_SYMBOL(dasd_enable_device);
/*
* SECTION: device operation (interrupt handler, start i/o, term i/o ...)
*/
unsigned int dasd_global_profile_level = DASD_PROFILE_OFF;
#ifdef CONFIG_DASD_PROFILE
struct dasd_profile dasd_global_profile = {
.lock = __SPIN_LOCK_UNLOCKED(dasd_global_profile.lock),
};
static struct dentry *dasd_debugfs_global_entry;
/*
* Add profiling information for cqr before execution.
*/
static void dasd_profile_start(struct dasd_block *block,
struct dasd_ccw_req *cqr,
struct request *req)
{
struct list_head *l;
unsigned int counter;
struct dasd_device *device;
/* count the length of the chanq for statistics */
counter = 0;
if (dasd_global_profile_level || block->profile.data)
list_for_each(l, &block->ccw_queue)
if (++counter >= 31)
break;
spin_lock(&dasd_global_profile.lock);
if (dasd_global_profile.data) {
dasd_global_profile.data->dasd_io_nr_req[counter]++;
if (rq_data_dir(req) == READ)
dasd_global_profile.data->dasd_read_nr_req[counter]++;
}
spin_unlock(&dasd_global_profile.lock);
spin_lock(&block->profile.lock);
if (block->profile.data) {
block->profile.data->dasd_io_nr_req[counter]++;
if (rq_data_dir(req) == READ)
block->profile.data->dasd_read_nr_req[counter]++;
}
spin_unlock(&block->profile.lock);
/*
* We count the request for the start device, even though it may run on
* some other device due to error recovery. This way we make sure that
* we count each request only once.
*/
device = cqr->startdev;
if (device->profile.data) {
counter = 1; /* request is not yet queued on the start device */
list_for_each(l, &device->ccw_queue)
if (++counter >= 31)
break;
}
spin_lock(&device->profile.lock);
if (device->profile.data) {
device->profile.data->dasd_io_nr_req[counter]++;
if (rq_data_dir(req) == READ)
device->profile.data->dasd_read_nr_req[counter]++;
}
spin_unlock(&device->profile.lock);
}
/*
* Add profiling information for cqr after execution.
*/
#define dasd_profile_counter(value, index) \
{ \
for (index = 0; index < 31 && value >> (2+index); index++) \
; \
}
static void dasd_profile_end_add_data(struct dasd_profile_info *data,
int is_alias,
int is_tpm,
int is_read,
long sectors,
int sectors_ind,
int tottime_ind,
int tottimeps_ind,
int strtime_ind,
int irqtime_ind,
int irqtimeps_ind,
int endtime_ind)
{
/* in case of an overflow, reset the whole profile */
if (data->dasd_io_reqs == UINT_MAX) {
memset(data, 0, sizeof(*data));
ktime_get_real_ts64(&data->starttod);
}
data->dasd_io_reqs++;
data->dasd_io_sects += sectors;
if (is_alias)
data->dasd_io_alias++;
if (is_tpm)
data->dasd_io_tpm++;
data->dasd_io_secs[sectors_ind]++;
data->dasd_io_times[tottime_ind]++;
data->dasd_io_timps[tottimeps_ind]++;
data->dasd_io_time1[strtime_ind]++;
data->dasd_io_time2[irqtime_ind]++;
data->dasd_io_time2ps[irqtimeps_ind]++;
data->dasd_io_time3[endtime_ind]++;
if (is_read) {
data->dasd_read_reqs++;
data->dasd_read_sects += sectors;
if (is_alias)
data->dasd_read_alias++;
if (is_tpm)
data->dasd_read_tpm++;
data->dasd_read_secs[sectors_ind]++;
data->dasd_read_times[tottime_ind]++;
data->dasd_read_time1[strtime_ind]++;
data->dasd_read_time2[irqtime_ind]++;
data->dasd_read_time3[endtime_ind]++;
}
}
static void dasd_profile_end(struct dasd_block *block,
struct dasd_ccw_req *cqr,
struct request *req)
{
unsigned long strtime, irqtime, endtime, tottime;
unsigned long tottimeps, sectors;
struct dasd_device *device;
int sectors_ind, tottime_ind, tottimeps_ind, strtime_ind;
int irqtime_ind, irqtimeps_ind, endtime_ind;
struct dasd_profile_info *data;
device = cqr->startdev;
if (!(dasd_global_profile_level ||
block->profile.data ||
device->profile.data))
return;
sectors = blk_rq_sectors(req);
if (!cqr->buildclk || !cqr->startclk ||
!cqr->stopclk || !cqr->endclk ||
!sectors)
return;
strtime = ((cqr->startclk - cqr->buildclk) >> 12);
irqtime = ((cqr->stopclk - cqr->startclk) >> 12);
endtime = ((cqr->endclk - cqr->stopclk) >> 12);
tottime = ((cqr->endclk - cqr->buildclk) >> 12);
tottimeps = tottime / sectors;
dasd_profile_counter(sectors, sectors_ind);
dasd_profile_counter(tottime, tottime_ind);
dasd_profile_counter(tottimeps, tottimeps_ind);
dasd_profile_counter(strtime, strtime_ind);
dasd_profile_counter(irqtime, irqtime_ind);
dasd_profile_counter(irqtime / sectors, irqtimeps_ind);
dasd_profile_counter(endtime, endtime_ind);
spin_lock(&dasd_global_profile.lock);
if (dasd_global_profile.data) {
data = dasd_global_profile.data;
data->dasd_sum_times += tottime;
data->dasd_sum_time_str += strtime;
data->dasd_sum_time_irq += irqtime;
data->dasd_sum_time_end += endtime;
dasd_profile_end_add_data(dasd_global_profile.data,
cqr->startdev != block->base,
cqr->cpmode == 1,
rq_data_dir(req) == READ,
sectors, sectors_ind, tottime_ind,
tottimeps_ind, strtime_ind,
irqtime_ind, irqtimeps_ind,
endtime_ind);
}
spin_unlock(&dasd_global_profile.lock);
spin_lock(&block->profile.lock);
if (block->profile.data) {
data = block->profile.data;
data->dasd_sum_times += tottime;
data->dasd_sum_time_str += strtime;
data->dasd_sum_time_irq += irqtime;
data->dasd_sum_time_end += endtime;
dasd_profile_end_add_data(block->profile.data,
cqr->startdev != block->base,
cqr->cpmode == 1,
rq_data_dir(req) == READ,
sectors, sectors_ind, tottime_ind,
tottimeps_ind, strtime_ind,
irqtime_ind, irqtimeps_ind,
endtime_ind);
}
spin_unlock(&block->profile.lock);
spin_lock(&device->profile.lock);
if (device->profile.data) {
data = device->profile.data;
data->dasd_sum_times += tottime;
data->dasd_sum_time_str += strtime;
data->dasd_sum_time_irq += irqtime;
data->dasd_sum_time_end += endtime;
dasd_profile_end_add_data(device->profile.data,
cqr->startdev != block->base,
cqr->cpmode == 1,
rq_data_dir(req) == READ,
sectors, sectors_ind, tottime_ind,
tottimeps_ind, strtime_ind,
irqtime_ind, irqtimeps_ind,
endtime_ind);
}
spin_unlock(&device->profile.lock);
}
void dasd_profile_reset(struct dasd_profile *profile)
{
struct dasd_profile_info *data;
spin_lock_bh(&profile->lock);
data = profile->data;
if (!data) {
spin_unlock_bh(&profile->lock);
return;
}
memset(data, 0, sizeof(*data));
ktime_get_real_ts64(&data->starttod);
spin_unlock_bh(&profile->lock);
}
int dasd_profile_on(struct dasd_profile *profile)
{
struct dasd_profile_info *data;
data = kzalloc(sizeof(*data), GFP_KERNEL);
if (!data)
return -ENOMEM;
spin_lock_bh(&profile->lock);
if (profile->data) {
spin_unlock_bh(&profile->lock);
kfree(data);
return 0;
}
ktime_get_real_ts64(&data->starttod);
profile->data = data;
spin_unlock_bh(&profile->lock);
return 0;
}
void dasd_profile_off(struct dasd_profile *profile)
{
spin_lock_bh(&profile->lock);
kfree(profile->data);
profile->data = NULL;
spin_unlock_bh(&profile->lock);
}
char *dasd_get_user_string(const char __user *user_buf, size_t user_len)
{
char *buffer;
buffer = vmalloc(user_len + 1);
if (buffer == NULL)
return ERR_PTR(-ENOMEM);
if (copy_from_user(buffer, user_buf, user_len) != 0) {
vfree(buffer);
return ERR_PTR(-EFAULT);
}
/* got the string, now strip linefeed. */
if (buffer[user_len - 1] == '\n')
buffer[user_len - 1] = 0;
else
buffer[user_len] = 0;
return buffer;
}
static ssize_t dasd_stats_write(struct file *file,
const char __user *user_buf,
size_t user_len, loff_t *pos)
{
char *buffer, *str;
int rc;
struct seq_file *m = (struct seq_file *)file->private_data;
struct dasd_profile *prof = m->private;
if (user_len > 65536)
user_len = 65536;
buffer = dasd_get_user_string(user_buf, user_len);
if (IS_ERR(buffer))
return PTR_ERR(buffer);
str = skip_spaces(buffer);
rc = user_len;
if (strncmp(str, "reset", 5) == 0) {
dasd_profile_reset(prof);
} else if (strncmp(str, "on", 2) == 0) {
rc = dasd_profile_on(prof);
if (rc)
goto out;
rc = user_len;
if (prof == &dasd_global_profile) {
dasd_profile_reset(prof);
dasd_global_profile_level = DASD_PROFILE_GLOBAL_ONLY;
}
} else if (strncmp(str, "off", 3) == 0) {
if (prof == &dasd_global_profile)
dasd_global_profile_level = DASD_PROFILE_OFF;
dasd_profile_off(prof);
} else
rc = -EINVAL;
out:
vfree(buffer);
return rc;
}
static void dasd_stats_array(struct seq_file *m, unsigned int *array)
{
int i;
for (i = 0; i < 32; i++)
seq_printf(m, "%u ", array[i]);
seq_putc(m, '\n');
}
static void dasd_stats_seq_print(struct seq_file *m,
struct dasd_profile_info *data)
{
seq_printf(m, "start_time %lld.%09ld\n",
(s64)data->starttod.tv_sec, data->starttod.tv_nsec);
seq_printf(m, "total_requests %u\n", data->dasd_io_reqs);
seq_printf(m, "total_sectors %u\n", data->dasd_io_sects);
seq_printf(m, "total_pav %u\n", data->dasd_io_alias);
seq_printf(m, "total_hpf %u\n", data->dasd_io_tpm);
seq_printf(m, "avg_total %lu\n", data->dasd_io_reqs ?
data->dasd_sum_times / data->dasd_io_reqs : 0UL);
seq_printf(m, "avg_build_to_ssch %lu\n", data->dasd_io_reqs ?
data->dasd_sum_time_str / data->dasd_io_reqs : 0UL);
seq_printf(m, "avg_ssch_to_irq %lu\n", data->dasd_io_reqs ?
data->dasd_sum_time_irq / data->dasd_io_reqs : 0UL);
seq_printf(m, "avg_irq_to_end %lu\n", data->dasd_io_reqs ?
data->dasd_sum_time_end / data->dasd_io_reqs : 0UL);
seq_puts(m, "histogram_sectors ");
dasd_stats_array(m, data->dasd_io_secs);
seq_puts(m, "histogram_io_times ");
dasd_stats_array(m, data->dasd_io_times);
seq_puts(m, "histogram_io_times_weighted ");
dasd_stats_array(m, data->dasd_io_timps);
seq_puts(m, "histogram_time_build_to_ssch ");
dasd_stats_array(m, data->dasd_io_time1);
seq_puts(m, "histogram_time_ssch_to_irq ");
dasd_stats_array(m, data->dasd_io_time2);
seq_puts(m, "histogram_time_ssch_to_irq_weighted ");
dasd_stats_array(m, data->dasd_io_time2ps);
seq_puts(m, "histogram_time_irq_to_end ");
dasd_stats_array(m, data->dasd_io_time3);
seq_puts(m, "histogram_ccw_queue_length ");
dasd_stats_array(m, data->dasd_io_nr_req);
seq_printf(m, "total_read_requests %u\n", data->dasd_read_reqs);
seq_printf(m, "total_read_sectors %u\n", data->dasd_read_sects);
seq_printf(m, "total_read_pav %u\n", data->dasd_read_alias);
seq_printf(m, "total_read_hpf %u\n", data->dasd_read_tpm);
seq_puts(m, "histogram_read_sectors ");
dasd_stats_array(m, data->dasd_read_secs);
seq_puts(m, "histogram_read_times ");
dasd_stats_array(m, data->dasd_read_times);
seq_puts(m, "histogram_read_time_build_to_ssch ");
dasd_stats_array(m, data->dasd_read_time1);
seq_puts(m, "histogram_read_time_ssch_to_irq ");
dasd_stats_array(m, data->dasd_read_time2);
seq_puts(m, "histogram_read_time_irq_to_end ");
dasd_stats_array(m, data->dasd_read_time3);
seq_puts(m, "histogram_read_ccw_queue_length ");
dasd_stats_array(m, data->dasd_read_nr_req);
}
static int dasd_stats_show(struct seq_file *m, void *v)
{
struct dasd_profile *profile;
struct dasd_profile_info *data;
profile = m->private;
spin_lock_bh(&profile->lock);
data = profile->data;
if (!data) {
spin_unlock_bh(&profile->lock);
seq_puts(m, "disabled\n");
return 0;
}
dasd_stats_seq_print(m, data);
spin_unlock_bh(&profile->lock);
return 0;
}
static int dasd_stats_open(struct inode *inode, struct file *file)
{
struct dasd_profile *profile = inode->i_private;
return single_open(file, dasd_stats_show, profile);
}
static const struct file_operations dasd_stats_raw_fops = {
.owner = THIS_MODULE,
.open = dasd_stats_open,
.read = seq_read,
.llseek = seq_lseek,
.release = single_release,
.write = dasd_stats_write,
};
static void dasd_profile_init(struct dasd_profile *profile,
struct dentry *base_dentry)
{
umode_t mode;
struct dentry *pde;
if (!base_dentry)
return;
profile->dentry = NULL;
profile->data = NULL;
mode = (S_IRUSR | S_IWUSR | S_IFREG);
pde = debugfs_create_file("statistics", mode, base_dentry,
profile, &dasd_stats_raw_fops);
if (pde && !IS_ERR(pde))
profile->dentry = pde;
return;
}
static void dasd_profile_exit(struct dasd_profile *profile)
{
dasd_profile_off(profile);
debugfs_remove(profile->dentry);
profile->dentry = NULL;
}
static void dasd_statistics_removeroot(void)
{
dasd_global_profile_level = DASD_PROFILE_OFF;
dasd_profile_exit(&dasd_global_profile);
debugfs_remove(dasd_debugfs_global_entry);
debugfs_remove(dasd_debugfs_root_entry);
}
static void dasd_statistics_createroot(void)
{
struct dentry *pde;
dasd_debugfs_root_entry = NULL;
pde = debugfs_create_dir("dasd", NULL);
if (!pde || IS_ERR(pde))
goto error;
dasd_debugfs_root_entry = pde;
pde = debugfs_create_dir("global", dasd_debugfs_root_entry);
if (!pde || IS_ERR(pde))
goto error;
dasd_debugfs_global_entry = pde;
dasd_profile_init(&dasd_global_profile, dasd_debugfs_global_entry);
return;
error:
DBF_EVENT(DBF_ERR, "%s",
"Creation of the dasd debugfs interface failed");
dasd_statistics_removeroot();
return;
}
#else
#define dasd_profile_start(block, cqr, req) do {} while (0)
#define dasd_profile_end(block, cqr, req) do {} while (0)
static void dasd_statistics_createroot(void)
{
return;
}
static void dasd_statistics_removeroot(void)
{
return;
}
int dasd_stats_generic_show(struct seq_file *m, void *v)
{
seq_puts(m, "Statistics are not activated in this kernel\n");
return 0;
}
static void dasd_profile_init(struct dasd_profile *profile,
struct dentry *base_dentry)
{
return;
}
static void dasd_profile_exit(struct dasd_profile *profile)
{
return;
}
int dasd_profile_on(struct dasd_profile *profile)
{
return 0;
}
#endif /* CONFIG_DASD_PROFILE */
static int dasd_hosts_show(struct seq_file *m, void *v)
{
struct dasd_device *device;
int rc = -EOPNOTSUPP;
device = m->private;
dasd_get_device(device);
if (device->discipline->hosts_print)
rc = device->discipline->hosts_print(device, m);
dasd_put_device(device);
return rc;
}
static int dasd_hosts_open(struct inode *inode, struct file *file)
{
struct dasd_device *device = inode->i_private;
return single_open(file, dasd_hosts_show, device);
}
static const struct file_operations dasd_hosts_fops = {
.owner = THIS_MODULE,
.open = dasd_hosts_open,
.read = seq_read,
.llseek = seq_lseek,
.release = single_release,
};
static void dasd_hosts_exit(struct dasd_device *device)
{
debugfs_remove(device->hosts_dentry);
device->hosts_dentry = NULL;
}
static void dasd_hosts_init(struct dentry *base_dentry,
struct dasd_device *device)
{
struct dentry *pde;
umode_t mode;
if (!base_dentry)
return;
mode = S_IRUSR | S_IFREG;
pde = debugfs_create_file("host_access_list", mode, base_dentry,
device, &dasd_hosts_fops);
if (pde && !IS_ERR(pde))
device->hosts_dentry = pde;
}
struct dasd_ccw_req *dasd_smalloc_request(int magic, int cplength, int datasize,
struct dasd_device *device,
struct dasd_ccw_req *cqr)
{
unsigned long flags;
char *data, *chunk;
int size = 0;
if (cplength > 0)
size += cplength * sizeof(struct ccw1);
if (datasize > 0)
size += datasize;
if (!cqr)
size += (sizeof(*cqr) + 7L) & -8L;
spin_lock_irqsave(&device->mem_lock, flags);
data = chunk = dasd_alloc_chunk(&device->ccw_chunks, size);
spin_unlock_irqrestore(&device->mem_lock, flags);
if (!chunk)
return ERR_PTR(-ENOMEM);
if (!cqr) {
cqr = (void *) data;
data += (sizeof(*cqr) + 7L) & -8L;
}
memset(cqr, 0, sizeof(*cqr));
cqr->mem_chunk = chunk;
if (cplength > 0) {
cqr->cpaddr = data;
data += cplength * sizeof(struct ccw1);
memset(cqr->cpaddr, 0, cplength * sizeof(struct ccw1));
}
if (datasize > 0) {
cqr->data = data;
memset(cqr->data, 0, datasize);
}
cqr->magic = magic;
set_bit(DASD_CQR_FLAGS_USE_ERP, &cqr->flags);
dasd_get_device(device);
return cqr;
}
EXPORT_SYMBOL(dasd_smalloc_request);
void dasd_sfree_request(struct dasd_ccw_req *cqr, struct dasd_device *device)
{
unsigned long flags;
spin_lock_irqsave(&device->mem_lock, flags);
dasd_free_chunk(&device->ccw_chunks, cqr->mem_chunk);
spin_unlock_irqrestore(&device->mem_lock, flags);
dasd_put_device(device);
}
EXPORT_SYMBOL(dasd_sfree_request);
/*
* Check discipline magic in cqr.
*/
static inline int dasd_check_cqr(struct dasd_ccw_req *cqr)
{
struct dasd_device *device;
if (cqr == NULL)
return -EINVAL;
device = cqr->startdev;
if (strncmp((char *) &cqr->magic, device->discipline->ebcname, 4)) {
DBF_DEV_EVENT(DBF_WARNING, device,
" dasd_ccw_req 0x%08x magic doesn't match"
" discipline 0x%08x",
cqr->magic,
*(unsigned int *) device->discipline->name);
return -EINVAL;
}
return 0;
}
/*
* Terminate the current i/o and set the request to clear_pending.
* Timer keeps device runnig.
* ccw_device_clear can fail if the i/o subsystem
* is in a bad mood.
*/
int dasd_term_IO(struct dasd_ccw_req *cqr)
{
struct dasd_device *device;
int retries, rc;
char errorstring[ERRORLENGTH];
/* Check the cqr */
rc = dasd_check_cqr(cqr);
if (rc)
return rc;
retries = 0;
device = (struct dasd_device *) cqr->startdev;
while ((retries < 5) && (cqr->status == DASD_CQR_IN_IO)) {
rc = ccw_device_clear(device->cdev, (long) cqr);
switch (rc) {
case 0: /* termination successful */
cqr->status = DASD_CQR_CLEAR_PENDING;
cqr->stopclk = get_tod_clock();
cqr->starttime = 0;
DBF_DEV_EVENT(DBF_DEBUG, device,
"terminate cqr %p successful",
cqr);
break;
case -ENODEV:
DBF_DEV_EVENT(DBF_ERR, device, "%s",
"device gone, retry");
break;
case -EINVAL:
/*
* device not valid so no I/O could be running
* handle CQR as termination successful
*/
cqr->status = DASD_CQR_CLEARED;
cqr->stopclk = get_tod_clock();
cqr->starttime = 0;
/* no retries for invalid devices */
cqr->retries = -1;
DBF_DEV_EVENT(DBF_ERR, device, "%s",
"EINVAL, handle as terminated");
/* fake rc to success */
rc = 0;
break;
default:
/* internal error 10 - unknown rc*/
snprintf(errorstring, ERRORLENGTH, "10 %d", rc);
dev_err(&device->cdev->dev, "An error occurred in the "
"DASD device driver, reason=%s\n", errorstring);
BUG();
break;
}
retries++;
}
dasd_schedule_device_bh(device);
return rc;
}
EXPORT_SYMBOL(dasd_term_IO);
/*
* Start the i/o. This start_IO can fail if the channel is really busy.
* In that case set up a timer to start the request later.
*/
int dasd_start_IO(struct dasd_ccw_req *cqr)
{
struct dasd_device *device;
int rc;
char errorstring[ERRORLENGTH];
/* Check the cqr */
rc = dasd_check_cqr(cqr);
if (rc) {
cqr->intrc = rc;
return rc;
}
device = (struct dasd_device *) cqr->startdev;
if (((cqr->block &&
test_bit(DASD_FLAG_LOCK_STOLEN, &cqr->block->base->flags)) ||
test_bit(DASD_FLAG_LOCK_STOLEN, &device->flags)) &&
!test_bit(DASD_CQR_ALLOW_SLOCK, &cqr->flags)) {
DBF_DEV_EVENT(DBF_DEBUG, device, "start_IO: return request %p "
"because of stolen lock", cqr);
cqr->status = DASD_CQR_ERROR;
cqr->intrc = -EPERM;
return -EPERM;
}
if (cqr->retries < 0) {
/* internal error 14 - start_IO run out of retries */
sprintf(errorstring, "14 %p", cqr);
dev_err(&device->cdev->dev, "An error occurred in the DASD "
"device driver, reason=%s\n", errorstring);
cqr->status = DASD_CQR_ERROR;
return -EIO;
}
cqr->startclk = get_tod_clock();
cqr->starttime = jiffies;
cqr->retries--;
if (!test_bit(DASD_CQR_VERIFY_PATH, &cqr->flags)) {
cqr->lpm &= dasd_path_get_opm(device);
if (!cqr->lpm)
cqr->lpm = dasd_path_get_opm(device);
}
if (cqr->cpmode == 1) {
rc = ccw_device_tm_start(device->cdev, cqr->cpaddr,
(long) cqr, cqr->lpm);
} else {
rc = ccw_device_start(device->cdev, cqr->cpaddr,
(long) cqr, cqr->lpm, 0);
}
switch (rc) {
case 0:
cqr->status = DASD_CQR_IN_IO;
break;
case -EBUSY:
DBF_DEV_EVENT(DBF_WARNING, device, "%s",
"start_IO: device busy, retry later");
break;
case -EACCES:
/* -EACCES indicates that the request used only a subset of the
* available paths and all these paths are gone. If the lpm of
* this request was only a subset of the opm (e.g. the ppm) then
* we just do a retry with all available paths.
* If we already use the full opm, something is amiss, and we
* need a full path verification.
*/
if (test_bit(DASD_CQR_VERIFY_PATH, &cqr->flags)) {
DBF_DEV_EVENT(DBF_WARNING, device,
"start_IO: selected paths gone (%x)",
cqr->lpm);
} else if (cqr->lpm != dasd_path_get_opm(device)) {
cqr->lpm = dasd_path_get_opm(device);
DBF_DEV_EVENT(DBF_DEBUG, device, "%s",
"start_IO: selected paths gone,"
" retry on all paths");
} else {
DBF_DEV_EVENT(DBF_WARNING, device, "%s",
"start_IO: all paths in opm gone,"
" do path verification");
dasd_generic_last_path_gone(device);
dasd_path_no_path(device);
dasd_path_set_tbvpm(device,
ccw_device_get_path_mask(
device->cdev));
}
break;
case -ENODEV:
DBF_DEV_EVENT(DBF_WARNING, device, "%s",
"start_IO: -ENODEV device gone, retry");
break;
case -EIO:
DBF_DEV_EVENT(DBF_WARNING, device, "%s",
"start_IO: -EIO device gone, retry");
break;
case -EINVAL:
/* most likely caused in power management context */
DBF_DEV_EVENT(DBF_WARNING, device, "%s",
"start_IO: -EINVAL device currently "
"not accessible");
break;
default:
/* internal error 11 - unknown rc */
snprintf(errorstring, ERRORLENGTH, "11 %d", rc);
dev_err(&device->cdev->dev,
"An error occurred in the DASD device driver, "
"reason=%s\n", errorstring);
BUG();
break;
}
cqr->intrc = rc;
return rc;
}
EXPORT_SYMBOL(dasd_start_IO);
/*
* Timeout function for dasd devices. This is used for different purposes
* 1) missing interrupt handler for normal operation
* 2) delayed start of request where start_IO failed with -EBUSY
* 3) timeout for missing state change interrupts
* The head of the ccw queue will have status DASD_CQR_IN_IO for 1),
* DASD_CQR_QUEUED for 2) and 3).
*/
static void dasd_device_timeout(struct timer_list *t)
{
unsigned long flags;
struct dasd_device *device;
device = from_timer(device, t, timer);
spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags);
/* re-activate request queue */
dasd_device_remove_stop_bits(device, DASD_STOPPED_PENDING);
spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
dasd_schedule_device_bh(device);
}
/*
* Setup timeout for a device in jiffies.
*/
void dasd_device_set_timer(struct dasd_device *device, int expires)
{
if (expires == 0)
del_timer(&device->timer);
else
mod_timer(&device->timer, jiffies + expires);
}
EXPORT_SYMBOL(dasd_device_set_timer);
/*
* Clear timeout for a device.
*/
void dasd_device_clear_timer(struct dasd_device *device)
{
del_timer(&device->timer);
}
EXPORT_SYMBOL(dasd_device_clear_timer);
static void dasd_handle_killed_request(struct ccw_device *cdev,
unsigned long intparm)
{
struct dasd_ccw_req *cqr;
struct dasd_device *device;
if (!intparm)
return;
cqr = (struct dasd_ccw_req *) intparm;
if (cqr->status != DASD_CQR_IN_IO) {
DBF_EVENT_DEVID(DBF_DEBUG, cdev,
"invalid status in handle_killed_request: "
"%02x", cqr->status);
return;
}
device = dasd_device_from_cdev_locked(cdev);
if (IS_ERR(device)) {
DBF_EVENT_DEVID(DBF_DEBUG, cdev, "%s",
"unable to get device from cdev");
return;
}
if (!cqr->startdev ||
device != cqr->startdev ||
strncmp(cqr->startdev->discipline->ebcname,
(char *) &cqr->magic, 4)) {
DBF_EVENT_DEVID(DBF_DEBUG, cdev, "%s",
"invalid device in request");
dasd_put_device(device);
return;
}
/* Schedule request to be retried. */
cqr->status = DASD_CQR_QUEUED;
dasd_device_clear_timer(device);
dasd_schedule_device_bh(device);
dasd_put_device(device);
}
void dasd_generic_handle_state_change(struct dasd_device *device)
{
/* First of all start sense subsystem status request. */
dasd_eer_snss(device);
dasd_device_remove_stop_bits(device, DASD_STOPPED_PENDING);
dasd_schedule_device_bh(device);
if (device->block) {
dasd_schedule_block_bh(device->block);
if (device->block->request_queue)
blk_mq_run_hw_queues(device->block->request_queue,
true);
}
}
EXPORT_SYMBOL_GPL(dasd_generic_handle_state_change);
static int dasd_check_hpf_error(struct irb *irb)
{
return (scsw_tm_is_valid_schxs(&irb->scsw) &&
(irb->scsw.tm.sesq == SCSW_SESQ_DEV_NOFCX ||
irb->scsw.tm.sesq == SCSW_SESQ_PATH_NOFCX));
}
/*
* Interrupt handler for "normal" ssch-io based dasd devices.
*/
void dasd_int_handler(struct ccw_device *cdev, unsigned long intparm,
struct irb *irb)
{
struct dasd_ccw_req *cqr, *next;
struct dasd_device *device;
unsigned long now;
int nrf_suppressed = 0;
int fp_suppressed = 0;
u8 *sense = NULL;
int expires;
cqr = (struct dasd_ccw_req *) intparm;
if (IS_ERR(irb)) {
switch (PTR_ERR(irb)) {
case -EIO:
if (cqr && cqr->status == DASD_CQR_CLEAR_PENDING) {
device = cqr->startdev;
cqr->status = DASD_CQR_CLEARED;
dasd_device_clear_timer(device);
wake_up(&dasd_flush_wq);
dasd_schedule_device_bh(device);
return;
}
break;
case -ETIMEDOUT:
DBF_EVENT_DEVID(DBF_WARNING, cdev, "%s: "
"request timed out\n", __func__);
break;
default:
DBF_EVENT_DEVID(DBF_WARNING, cdev, "%s: "
"unknown error %ld\n", __func__,
PTR_ERR(irb));
}
dasd_handle_killed_request(cdev, intparm);
return;
}
now = get_tod_clock();
/* check for conditions that should be handled immediately */
if (!cqr ||
!(scsw_dstat(&irb->scsw) == (DEV_STAT_CHN_END | DEV_STAT_DEV_END) &&
scsw_cstat(&irb->scsw) == 0)) {
if (cqr)
memcpy(&cqr->irb, irb, sizeof(*irb));
device = dasd_device_from_cdev_locked(cdev);
if (IS_ERR(device))
return;
/* ignore unsolicited interrupts for DIAG discipline */
if (device->discipline == dasd_diag_discipline_pointer) {
dasd_put_device(device);
return;
}
/*
* In some cases 'File Protected' or 'No Record Found' errors
* might be expected and debug log messages for the
* corresponding interrupts shouldn't be written then.
* Check if either of the according suppress bits is set.
*/
sense = dasd_get_sense(irb);
if (sense) {
fp_suppressed = (sense[1] & SNS1_FILE_PROTECTED) &&
test_bit(DASD_CQR_SUPPRESS_FP, &cqr->flags);
nrf_suppressed = (sense[1] & SNS1_NO_REC_FOUND) &&
test_bit(DASD_CQR_SUPPRESS_NRF, &cqr->flags);
}
if (!(fp_suppressed || nrf_suppressed))
device->discipline->dump_sense_dbf(device, irb, "int");
if (device->features & DASD_FEATURE_ERPLOG)
device->discipline->dump_sense(device, cqr, irb);
device->discipline->check_for_device_change(device, cqr, irb);
dasd_put_device(device);
}
/* check for for attention message */
if (scsw_dstat(&irb->scsw) & DEV_STAT_ATTENTION) {
device = dasd_device_from_cdev_locked(cdev);
if (!IS_ERR(device)) {
device->discipline->check_attention(device,
irb->esw.esw1.lpum);
dasd_put_device(device);
}
}
if (!cqr)
return;
device = (struct dasd_device *) cqr->startdev;
if (!device ||
strncmp(device->discipline->ebcname, (char *) &cqr->magic, 4)) {
DBF_EVENT_DEVID(DBF_DEBUG, cdev, "%s",
"invalid device in request");
return;
}
/* Check for clear pending */
if (cqr->status == DASD_CQR_CLEAR_PENDING &&
scsw_fctl(&irb->scsw) & SCSW_FCTL_CLEAR_FUNC) {
cqr->status = DASD_CQR_CLEARED;
dasd_device_clear_timer(device);
wake_up(&dasd_flush_wq);
dasd_schedule_device_bh(device);
return;
}
/* check status - the request might have been killed by dyn detach */
if (cqr->status != DASD_CQR_IN_IO) {
DBF_DEV_EVENT(DBF_DEBUG, device, "invalid status: bus_id %s, "
"status %02x", dev_name(&cdev->dev), cqr->status);
return;
}
next = NULL;
expires = 0;
if (scsw_dstat(&irb->scsw) == (DEV_STAT_CHN_END | DEV_STAT_DEV_END) &&
scsw_cstat(&irb->scsw) == 0) {
/* request was completed successfully */
cqr->status = DASD_CQR_SUCCESS;
cqr->stopclk = now;
/* Start first request on queue if possible -> fast_io. */
if (cqr->devlist.next != &device->ccw_queue) {
next = list_entry(cqr->devlist.next,
struct dasd_ccw_req, devlist);
}
} else { /* error */
/* check for HPF error
* call discipline function to requeue all requests
* and disable HPF accordingly
*/
if (cqr->cpmode && dasd_check_hpf_error(irb) &&
device->discipline->handle_hpf_error)
device->discipline->handle_hpf_error(device, irb);
/*
* If we don't want complex ERP for this request, then just
* reset this and retry it in the fastpath
*/
if (!test_bit(DASD_CQR_FLAGS_USE_ERP, &cqr->flags) &&
cqr->retries > 0) {
if (cqr->lpm == dasd_path_get_opm(device))
DBF_DEV_EVENT(DBF_DEBUG, device,
"default ERP in fastpath "
"(%i retries left)",
cqr->retries);
if (!test_bit(DASD_CQR_VERIFY_PATH, &cqr->flags))
cqr->lpm = dasd_path_get_opm(device);
cqr->status = DASD_CQR_QUEUED;
next = cqr;
} else
cqr->status = DASD_CQR_ERROR;
}
if (next && (next->status == DASD_CQR_QUEUED) &&
(!device->stopped)) {
if (device->discipline->start_IO(next) == 0)
expires = next->expires;
}
if (expires != 0)
dasd_device_set_timer(device, expires);
else
dasd_device_clear_timer(device);
dasd_schedule_device_bh(device);
}
EXPORT_SYMBOL(dasd_int_handler);
enum uc_todo dasd_generic_uc_handler(struct ccw_device *cdev, struct irb *irb)
{
struct dasd_device *device;
device = dasd_device_from_cdev_locked(cdev);
if (IS_ERR(device))
goto out;
if (test_bit(DASD_FLAG_OFFLINE, &device->flags) ||
device->state != device->target ||
!device->discipline->check_for_device_change){
dasd_put_device(device);
goto out;
}
if (device->discipline->dump_sense_dbf)
device->discipline->dump_sense_dbf(device, irb, "uc");
device->discipline->check_for_device_change(device, NULL, irb);
dasd_put_device(device);
out:
return UC_TODO_RETRY;
}
EXPORT_SYMBOL_GPL(dasd_generic_uc_handler);
/*
* If we have an error on a dasd_block layer request then we cancel
* and return all further requests from the same dasd_block as well.
*/
static void __dasd_device_recovery(struct dasd_device *device,
struct dasd_ccw_req *ref_cqr)
{
struct list_head *l, *n;
struct dasd_ccw_req *cqr;
/*
* only requeue request that came from the dasd_block layer
*/
if (!ref_cqr->block)
return;
list_for_each_safe(l, n, &device->ccw_queue) {
cqr = list_entry(l, struct dasd_ccw_req, devlist);
if (cqr->status == DASD_CQR_QUEUED &&
ref_cqr->block == cqr->block) {
cqr->status = DASD_CQR_CLEARED;
}
}
};
/*
* Remove those ccw requests from the queue that need to be returned
* to the upper layer.
*/
static void __dasd_device_process_ccw_queue(struct dasd_device *device,
struct list_head *final_queue)
{
struct list_head *l, *n;
struct dasd_ccw_req *cqr;
/* Process request with final status. */
list_for_each_safe(l, n, &device->ccw_queue) {
cqr = list_entry(l, struct dasd_ccw_req, devlist);
/* Skip any non-final request. */
if (cqr->status == DASD_CQR_QUEUED ||
cqr->status == DASD_CQR_IN_IO ||
cqr->status == DASD_CQR_CLEAR_PENDING)
continue;
if (cqr->status == DASD_CQR_ERROR) {
__dasd_device_recovery(device, cqr);
}
/* Rechain finished requests to final queue */
list_move_tail(&cqr->devlist, final_queue);
}
}
static void __dasd_process_cqr(struct dasd_device *device,
struct dasd_ccw_req *cqr)
{
char errorstring[ERRORLENGTH];
switch (cqr->status) {
case DASD_CQR_SUCCESS:
cqr->status = DASD_CQR_DONE;
break;
case DASD_CQR_ERROR:
cqr->status = DASD_CQR_NEED_ERP;
break;
case DASD_CQR_CLEARED:
cqr->status = DASD_CQR_TERMINATED;
break;
default:
/* internal error 12 - wrong cqr status*/
snprintf(errorstring, ERRORLENGTH, "12 %p %x02", cqr, cqr->status);
dev_err(&device->cdev->dev,
"An error occurred in the DASD device driver, "
"reason=%s\n", errorstring);
BUG();
}
if (cqr->callback)
cqr->callback(cqr, cqr->callback_data);
}
/*
* the cqrs from the final queue are returned to the upper layer
* by setting a dasd_block state and calling the callback function
*/
static void __dasd_device_process_final_queue(struct dasd_device *device,
struct list_head *final_queue)
{
struct list_head *l, *n;
struct dasd_ccw_req *cqr;
struct dasd_block *block;
list_for_each_safe(l, n, final_queue) {
cqr = list_entry(l, struct dasd_ccw_req, devlist);
list_del_init(&cqr->devlist);
block = cqr->block;
if (!block) {
__dasd_process_cqr(device, cqr);
} else {
spin_lock_bh(&block->queue_lock);
__dasd_process_cqr(device, cqr);
spin_unlock_bh(&block->queue_lock);
}
}
}
/*
* Take a look at the first request on the ccw queue and check
* if it reached its expire time. If so, terminate the IO.
*/
static void __dasd_device_check_expire(struct dasd_device *device)
{
struct dasd_ccw_req *cqr;
if (list_empty(&device->ccw_queue))
return;
cqr = list_entry(device->ccw_queue.next, struct dasd_ccw_req, devlist);
if ((cqr->status == DASD_CQR_IN_IO && cqr->expires != 0) &&
(time_after_eq(jiffies, cqr->expires + cqr->starttime))) {
if (test_bit(DASD_FLAG_SAFE_OFFLINE_RUNNING, &device->flags)) {
/*
* IO in safe offline processing should not
* run out of retries
*/
cqr->retries++;
}
if (device->discipline->term_IO(cqr) != 0) {
/* Hmpf, try again in 5 sec */
dev_err(&device->cdev->dev,
"cqr %p timed out (%lus) but cannot be "
"ended, retrying in 5 s\n",
cqr, (cqr->expires/HZ));
cqr->expires += 5*HZ;
dasd_device_set_timer(device, 5*HZ);
} else {
dev_err(&device->cdev->dev,
"cqr %p timed out (%lus), %i retries "
"remaining\n", cqr, (cqr->expires/HZ),
cqr->retries);
}
}
}
/*
* return 1 when device is not eligible for IO
*/
static int __dasd_device_is_unusable(struct dasd_device *device,
struct dasd_ccw_req *cqr)
{
int mask = ~(DASD_STOPPED_DC_WAIT | DASD_UNRESUMED_PM);
if (test_bit(DASD_FLAG_OFFLINE, &device->flags) &&
!test_bit(DASD_FLAG_SAFE_OFFLINE_RUNNING, &device->flags)) {
/*
* dasd is being set offline
* but it is no safe offline where we have to allow I/O
*/
return 1;
}
if (device->stopped) {
if (device->stopped & mask) {
/* stopped and CQR will not change that. */
return 1;
}
if (!test_bit(DASD_CQR_VERIFY_PATH, &cqr->flags)) {
/* CQR is not able to change device to
* operational. */
return 1;
}
/* CQR required to get device operational. */
}
return 0;
}
/*
* Take a look at the first request on the ccw queue and check
* if it needs to be started.
*/
static void __dasd_device_start_head(struct dasd_device *device)
{
struct dasd_ccw_req *cqr;
int rc;
if (list_empty(&device->ccw_queue))
return;
cqr = list_entry(device->ccw_queue.next, struct dasd_ccw_req, devlist);
if (cqr->status != DASD_CQR_QUEUED)
return;
/* if device is not usable return request to upper layer */
if (__dasd_device_is_unusable(device, cqr)) {
cqr->intrc = -EAGAIN;
cqr->status = DASD_CQR_CLEARED;
dasd_schedule_device_bh(device);
return;
}
rc = device->discipline->start_IO(cqr);
if (rc == 0)
dasd_device_set_timer(device, cqr->expires);
else if (rc == -EACCES) {
dasd_schedule_device_bh(device);
} else
/* Hmpf, try again in 1/2 sec */
dasd_device_set_timer(device, 50);
}
static void __dasd_device_check_path_events(struct dasd_device *device)
{
int rc;
if (!dasd_path_get_tbvpm(device))
return;
if (device->stopped &
~(DASD_STOPPED_DC_WAIT | DASD_UNRESUMED_PM))
return;
rc = device->discipline->verify_path(device,
dasd_path_get_tbvpm(device));
if (rc)
dasd_device_set_timer(device, 50);
else
dasd_path_clear_all_verify(device);
};
/*
* Go through all request on the dasd_device request queue,
* terminate them on the cdev if necessary, and return them to the
* submitting layer via callback.
* Note:
* Make sure that all 'submitting layers' still exist when
* this function is called!. In other words, when 'device' is a base
* device then all block layer requests must have been removed before
* via dasd_flush_block_queue.
*/
int dasd_flush_device_queue(struct dasd_device *device)
{
struct dasd_ccw_req *cqr, *n;
int rc;
struct list_head flush_queue;
INIT_LIST_HEAD(&flush_queue);
spin_lock_irq(get_ccwdev_lock(device->cdev));
rc = 0;
list_for_each_entry_safe(cqr, n, &device->ccw_queue, devlist) {
/* Check status and move request to flush_queue */
switch (cqr->status) {
case DASD_CQR_IN_IO:
rc = device->discipline->term_IO(cqr);
if (rc) {
/* unable to terminate requeust */
dev_err(&device->cdev->dev,
"Flushing the DASD request queue "
"failed for request %p\n", cqr);
/* stop flush processing */
goto finished;
}
break;
case DASD_CQR_QUEUED:
cqr->stopclk = get_tod_clock();
cqr->status = DASD_CQR_CLEARED;
break;
default: /* no need to modify the others */
break;
}
list_move_tail(&cqr->devlist, &flush_queue);
}
finished:
spin_unlock_irq(get_ccwdev_lock(device->cdev));
/*
* After this point all requests must be in state CLEAR_PENDING,
* CLEARED, SUCCESS or ERROR. Now wait for CLEAR_PENDING to become
* one of the others.
*/
list_for_each_entry_safe(cqr, n, &flush_queue, devlist)
wait_event(dasd_flush_wq,
(cqr->status != DASD_CQR_CLEAR_PENDING));
/*
* Now set each request back to TERMINATED, DONE or NEED_ERP
* and call the callback function of flushed requests
*/
__dasd_device_process_final_queue(device, &flush_queue);
return rc;
}
EXPORT_SYMBOL_GPL(dasd_flush_device_queue);
/*
* Acquire the device lock and process queues for the device.
*/
static void dasd_device_tasklet(unsigned long data)
{
struct dasd_device *device = (struct dasd_device *) data;
struct list_head final_queue;
atomic_set (&device->tasklet_scheduled, 0);
INIT_LIST_HEAD(&final_queue);
spin_lock_irq(get_ccwdev_lock(device->cdev));
/* Check expire time of first request on the ccw queue. */
__dasd_device_check_expire(device);
/* find final requests on ccw queue */
__dasd_device_process_ccw_queue(device, &final_queue);
__dasd_device_check_path_events(device);
spin_unlock_irq(get_ccwdev_lock(device->cdev));
/* Now call the callback function of requests with final status */
__dasd_device_process_final_queue(device, &final_queue);
spin_lock_irq(get_ccwdev_lock(device->cdev));
/* Now check if the head of the ccw queue needs to be started. */
__dasd_device_start_head(device);
spin_unlock_irq(get_ccwdev_lock(device->cdev));
if (waitqueue_active(&shutdown_waitq))
wake_up(&shutdown_waitq);
dasd_put_device(device);
}
/*
* Schedules a call to dasd_tasklet over the device tasklet.
*/
void dasd_schedule_device_bh(struct dasd_device *device)
{
/* Protect against rescheduling. */
if (atomic_cmpxchg (&device->tasklet_scheduled, 0, 1) != 0)
return;
dasd_get_device(device);
tasklet_hi_schedule(&device->tasklet);
}
EXPORT_SYMBOL(dasd_schedule_device_bh);
void dasd_device_set_stop_bits(struct dasd_device *device, int bits)
{
device->stopped |= bits;
}
EXPORT_SYMBOL_GPL(dasd_device_set_stop_bits);
void dasd_device_remove_stop_bits(struct dasd_device *device, int bits)
{
device->stopped &= ~bits;
if (!device->stopped)
wake_up(&generic_waitq);
}
EXPORT_SYMBOL_GPL(dasd_device_remove_stop_bits);
/*
* Queue a request to the head of the device ccw_queue.
* Start the I/O if possible.
*/
void dasd_add_request_head(struct dasd_ccw_req *cqr)
{
struct dasd_device *device;
unsigned long flags;
device = cqr->startdev;
spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags);
cqr->status = DASD_CQR_QUEUED;
list_add(&cqr->devlist, &device->ccw_queue);
/* let the bh start the request to keep them in order */
dasd_schedule_device_bh(device);
spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
}
EXPORT_SYMBOL(dasd_add_request_head);
/*
* Queue a request to the tail of the device ccw_queue.
* Start the I/O if possible.
*/
void dasd_add_request_tail(struct dasd_ccw_req *cqr)
{
struct dasd_device *device;
unsigned long flags;
device = cqr->startdev;
spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags);
cqr->status = DASD_CQR_QUEUED;
list_add_tail(&cqr->devlist, &device->ccw_queue);
/* let the bh start the request to keep them in order */
dasd_schedule_device_bh(device);
spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
}
EXPORT_SYMBOL(dasd_add_request_tail);
/*
* Wakeup helper for the 'sleep_on' functions.
*/
void dasd_wakeup_cb(struct dasd_ccw_req *cqr, void *data)
{
spin_lock_irq(get_ccwdev_lock(cqr->startdev->cdev));
cqr->callback_data = DASD_SLEEPON_END_TAG;
spin_unlock_irq(get_ccwdev_lock(cqr->startdev->cdev));
wake_up(&generic_waitq);
}
EXPORT_SYMBOL_GPL(dasd_wakeup_cb);
static inline int _wait_for_wakeup(struct dasd_ccw_req *cqr)
{
struct dasd_device *device;
int rc;
device = cqr->startdev;
spin_lock_irq(get_ccwdev_lock(device->cdev));
rc = (cqr->callback_data == DASD_SLEEPON_END_TAG);
spin_unlock_irq(get_ccwdev_lock(device->cdev));
return rc;
}
/*
* checks if error recovery is necessary, returns 1 if yes, 0 otherwise.
*/
static int __dasd_sleep_on_erp(struct dasd_ccw_req *cqr)
{
struct dasd_device *device;
dasd_erp_fn_t erp_fn;
if (cqr->status == DASD_CQR_FILLED)
return 0;
device = cqr->startdev;
if (test_bit(DASD_CQR_FLAGS_USE_ERP, &cqr->flags)) {
if (cqr->status == DASD_CQR_TERMINATED) {
device->discipline->handle_terminated_request(cqr);
return 1;
}
if (cqr->status == DASD_CQR_NEED_ERP) {
erp_fn = device->discipline->erp_action(cqr);
erp_fn(cqr);
return 1;
}
if (cqr->status == DASD_CQR_FAILED)
dasd_log_sense(cqr, &cqr->irb);
if (cqr->refers) {
__dasd_process_erp(device, cqr);
return 1;
}
}
return 0;
}
static int __dasd_sleep_on_loop_condition(struct dasd_ccw_req *cqr)
{
if (test_bit(DASD_CQR_FLAGS_USE_ERP, &cqr->flags)) {
if (cqr->refers) /* erp is not done yet */
return 1;
return ((cqr->status != DASD_CQR_DONE) &&
(cqr->status != DASD_CQR_FAILED));
} else
return (cqr->status == DASD_CQR_FILLED);
}
static int _dasd_sleep_on(struct dasd_ccw_req *maincqr, int interruptible)
{
struct dasd_device *device;
int rc;
struct list_head ccw_queue;
struct dasd_ccw_req *cqr;
INIT_LIST_HEAD(&ccw_queue);
maincqr->status = DASD_CQR_FILLED;
device = maincqr->startdev;
list_add(&maincqr->blocklist, &ccw_queue);
for (cqr = maincqr; __dasd_sleep_on_loop_condition(cqr);
cqr = list_first_entry(&ccw_queue,
struct dasd_ccw_req, blocklist)) {
if (__dasd_sleep_on_erp(cqr))
continue;
if (cqr->status != DASD_CQR_FILLED) /* could be failed */
continue;
if (test_bit(DASD_FLAG_LOCK_STOLEN, &device->flags) &&
!test_bit(DASD_CQR_ALLOW_SLOCK, &cqr->flags)) {
cqr->status = DASD_CQR_FAILED;
cqr->intrc = -EPERM;
continue;
}
/* Non-temporary stop condition will trigger fail fast */
if (device->stopped & ~DASD_STOPPED_PENDING &&
test_bit(DASD_CQR_FLAGS_FAILFAST, &cqr->flags) &&
(!dasd_eer_enabled(device))) {
cqr->status = DASD_CQR_FAILED;
cqr->intrc = -ENOLINK;
continue;
}
/*
* Don't try to start requests if device is in
* offline processing, it might wait forever
*/
if (test_bit(DASD_FLAG_OFFLINE, &device->flags)) {
cqr->status = DASD_CQR_FAILED;
cqr->intrc = -ENODEV;
continue;
}
/*
* Don't try to start requests if device is stopped
* except path verification requests
*/
if (!test_bit(DASD_CQR_VERIFY_PATH, &cqr->flags)) {
if (interruptible) {
rc = wait_event_interruptible(
generic_waitq, !(device->stopped));
if (rc == -ERESTARTSYS) {
cqr->status = DASD_CQR_FAILED;
maincqr->intrc = rc;
continue;
}
} else
wait_event(generic_waitq, !(device->stopped));
}
if (!cqr->callback)
cqr->callback = dasd_wakeup_cb;
cqr->callback_data = DASD_SLEEPON_START_TAG;
dasd_add_request_tail(cqr);
if (interruptible) {
rc = wait_event_interruptible(
generic_waitq, _wait_for_wakeup(cqr));
if (rc == -ERESTARTSYS) {
dasd_cancel_req(cqr);
/* wait (non-interruptible) for final status */
wait_event(generic_waitq,
_wait_for_wakeup(cqr));
cqr->status = DASD_CQR_FAILED;
maincqr->intrc = rc;
continue;
}
} else
wait_event(generic_waitq, _wait_for_wakeup(cqr));
}
maincqr->endclk = get_tod_clock();
if ((maincqr->status != DASD_CQR_DONE) &&
(maincqr->intrc != -ERESTARTSYS))
dasd_log_sense(maincqr, &maincqr->irb);
if (maincqr->status == DASD_CQR_DONE)
rc = 0;
else if (maincqr->intrc)
rc = maincqr->intrc;
else
rc = -EIO;
return rc;
}
static inline int _wait_for_wakeup_queue(struct list_head *ccw_queue)
{
struct dasd_ccw_req *cqr;
list_for_each_entry(cqr, ccw_queue, blocklist) {
if (cqr->callback_data != DASD_SLEEPON_END_TAG)
return 0;
}
return 1;
}
static int _dasd_sleep_on_queue(struct list_head *ccw_queue, int interruptible)
{
struct dasd_device *device;
struct dasd_ccw_req *cqr, *n;
u8 *sense = NULL;
int rc;
retry:
list_for_each_entry_safe(cqr, n, ccw_queue, blocklist) {
device = cqr->startdev;
if (cqr->status != DASD_CQR_FILLED) /*could be failed*/
continue;
if (test_bit(DASD_FLAG_LOCK_STOLEN, &device->flags) &&
!test_bit(DASD_CQR_ALLOW_SLOCK, &cqr->flags)) {
cqr->status = DASD_CQR_FAILED;
cqr->intrc = -EPERM;
continue;
}
/*Non-temporary stop condition will trigger fail fast*/
if (device->stopped & ~DASD_STOPPED_PENDING &&
test_bit(DASD_CQR_FLAGS_FAILFAST, &cqr->flags) &&
!dasd_eer_enabled(device)) {
cqr->status = DASD_CQR_FAILED;
cqr->intrc = -EAGAIN;
continue;
}
/*Don't try to start requests if device is stopped*/
if (interruptible) {
rc = wait_event_interruptible(
generic_waitq, !device->stopped);
if (rc == -ERESTARTSYS) {
cqr->status = DASD_CQR_FAILED;
cqr->intrc = rc;
continue;
}
} else
wait_event(generic_waitq, !(device->stopped));
if (!cqr->callback)
cqr->callback = dasd_wakeup_cb;
cqr->callback_data = DASD_SLEEPON_START_TAG;
dasd_add_request_tail(cqr);
}
wait_event(generic_waitq, _wait_for_wakeup_queue(ccw_queue));
rc = 0;
list_for_each_entry_safe(cqr, n, ccw_queue, blocklist) {
/*
* In some cases the 'File Protected' or 'Incorrect Length'
* error might be expected and error recovery would be
* unnecessary in these cases. Check if the according suppress
* bit is set.
*/
sense = dasd_get_sense(&cqr->irb);
if (sense && sense[1] & SNS1_FILE_PROTECTED &&
test_bit(DASD_CQR_SUPPRESS_FP, &cqr->flags))
continue;
if (scsw_cstat(&cqr->irb.scsw) == 0x40 &&
test_bit(DASD_CQR_SUPPRESS_IL, &cqr->flags))
continue;
/*
* for alias devices simplify error recovery and
* return to upper layer
* do not skip ERP requests
*/
if (cqr->startdev != cqr->basedev && !cqr->refers &&
(cqr->status == DASD_CQR_TERMINATED ||
cqr->status == DASD_CQR_NEED_ERP))
return -EAGAIN;
/* normal recovery for basedev IO */
if (__dasd_sleep_on_erp(cqr))
/* handle erp first */
goto retry;
}
return 0;
}
/*
* Queue a request to the tail of the device ccw_queue and wait for
* it's completion.
*/
int dasd_sleep_on(struct dasd_ccw_req *cqr)
{
return _dasd_sleep_on(cqr, 0);
}
EXPORT_SYMBOL(dasd_sleep_on);
/*
* Start requests from a ccw_queue and wait for their completion.
*/
int dasd_sleep_on_queue(struct list_head *ccw_queue)
{
return _dasd_sleep_on_queue(ccw_queue, 0);
}
EXPORT_SYMBOL(dasd_sleep_on_queue);
/*
* Queue a request to the tail of the device ccw_queue and wait
* interruptible for it's completion.
*/
int dasd_sleep_on_interruptible(struct dasd_ccw_req *cqr)
{
return _dasd_sleep_on(cqr, 1);
}
EXPORT_SYMBOL(dasd_sleep_on_interruptible);
/*
* Whoa nelly now it gets really hairy. For some functions (e.g. steal lock
* for eckd devices) the currently running request has to be terminated
* and be put back to status queued, before the special request is added
* to the head of the queue. Then the special request is waited on normally.
*/
static inline int _dasd_term_running_cqr(struct dasd_device *device)
{
struct dasd_ccw_req *cqr;
int rc;
if (list_empty(&device->ccw_queue))
return 0;
cqr = list_entry(device->ccw_queue.next, struct dasd_ccw_req, devlist);
rc = device->discipline->term_IO(cqr);
if (!rc)
/*
* CQR terminated because a more important request is pending.
* Undo decreasing of retry counter because this is
* not an error case.
*/
cqr->retries++;
return rc;
}
int dasd_sleep_on_immediatly(struct dasd_ccw_req *cqr)
{
struct dasd_device *device;
int rc;
device = cqr->startdev;
if (test_bit(DASD_FLAG_LOCK_STOLEN, &device->flags) &&
!test_bit(DASD_CQR_ALLOW_SLOCK, &cqr->flags)) {
cqr->status = DASD_CQR_FAILED;
cqr->intrc = -EPERM;
return -EIO;
}
spin_lock_irq(get_ccwdev_lock(device->cdev));
rc = _dasd_term_running_cqr(device);
if (rc) {
spin_unlock_irq(get_ccwdev_lock(device->cdev));
return rc;
}
cqr->callback = dasd_wakeup_cb;
cqr->callback_data = DASD_SLEEPON_START_TAG;
cqr->status = DASD_CQR_QUEUED;
/*
* add new request as second
* first the terminated cqr needs to be finished
*/
list_add(&cqr->devlist, device->ccw_queue.next);
/* let the bh start the request to keep them in order */
dasd_schedule_device_bh(device);
spin_unlock_irq(get_ccwdev_lock(device->cdev));
wait_event(generic_waitq, _wait_for_wakeup(cqr));
if (cqr->status == DASD_CQR_DONE)
rc = 0;
else if (cqr->intrc)
rc = cqr->intrc;
else
rc = -EIO;
/* kick tasklets */
dasd_schedule_device_bh(device);
if (device->block)
dasd_schedule_block_bh(device->block);
return rc;
}
EXPORT_SYMBOL(dasd_sleep_on_immediatly);
/*
* Cancels a request that was started with dasd_sleep_on_req.
* This is useful to timeout requests. The request will be
* terminated if it is currently in i/o.
* Returns 0 if request termination was successful
* negative error code if termination failed
* Cancellation of a request is an asynchronous operation! The calling
* function has to wait until the request is properly returned via callback.
*/
static int __dasd_cancel_req(struct dasd_ccw_req *cqr)
{
struct dasd_device *device = cqr->startdev;
int rc = 0;
switch (cqr->status) {
case DASD_CQR_QUEUED:
/* request was not started - just set to cleared */
cqr->status = DASD_CQR_CLEARED;
break;
case DASD_CQR_IN_IO:
/* request in IO - terminate IO and release again */
rc = device->discipline->term_IO(cqr);
if (rc) {
dev_err(&device->cdev->dev,
"Cancelling request %p failed with rc=%d\n",
cqr, rc);
} else {
cqr->stopclk = get_tod_clock();
}
break;
default: /* already finished or clear pending - do nothing */
break;
}
dasd_schedule_device_bh(device);
return rc;
}
int dasd_cancel_req(struct dasd_ccw_req *cqr)
{
struct dasd_device *device = cqr->startdev;
unsigned long flags;
int rc;
spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags);
rc = __dasd_cancel_req(cqr);
spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
return rc;
}
/*
* SECTION: Operations of the dasd_block layer.
*/
/*
* Timeout function for dasd_block. This is used when the block layer
* is waiting for something that may not come reliably, (e.g. a state
* change interrupt)
*/
static void dasd_block_timeout(struct timer_list *t)
{
unsigned long flags;
struct dasd_block *block;
block = from_timer(block, t, timer);
spin_lock_irqsave(get_ccwdev_lock(block->base->cdev), flags);
/* re-activate request queue */
dasd_device_remove_stop_bits(block->base, DASD_STOPPED_PENDING);
spin_unlock_irqrestore(get_ccwdev_lock(block->base->cdev), flags);
dasd_schedule_block_bh(block);
blk_mq_run_hw_queues(block->request_queue, true);
}
/*
* Setup timeout for a dasd_block in jiffies.
*/
void dasd_block_set_timer(struct dasd_block *block, int expires)
{
if (expires == 0)
del_timer(&block->timer);
else
mod_timer(&block->timer, jiffies + expires);
}
EXPORT_SYMBOL(dasd_block_set_timer);
/*
* Clear timeout for a dasd_block.
*/
void dasd_block_clear_timer(struct dasd_block *block)
{
del_timer(&block->timer);
}
EXPORT_SYMBOL(dasd_block_clear_timer);
/*
* Process finished error recovery ccw.
*/
static void __dasd_process_erp(struct dasd_device *device,
struct dasd_ccw_req *cqr)
{
dasd_erp_fn_t erp_fn;
if (cqr->status == DASD_CQR_DONE)
DBF_DEV_EVENT(DBF_NOTICE, device, "%s", "ERP successful");
else
dev_err(&device->cdev->dev, "ERP failed for the DASD\n");
erp_fn = device->discipline->erp_postaction(cqr);
erp_fn(cqr);
}
static void __dasd_cleanup_cqr(struct dasd_ccw_req *cqr)
{
struct request *req;
blk_status_t error = BLK_STS_OK;
int status;
req = (struct request *) cqr->callback_data;
dasd_profile_end(cqr->block, cqr, req);
status = cqr->block->base->discipline->free_cp(cqr, req);
if (status < 0)
error = errno_to_blk_status(status);
else if (status == 0) {
switch (cqr->intrc) {
case -EPERM:
error = BLK_STS_NEXUS;
break;
case -ENOLINK:
error = BLK_STS_TRANSPORT;
break;
case -ETIMEDOUT:
error = BLK_STS_TIMEOUT;
break;
default:
error = BLK_STS_IOERR;
break;
}
}
/*
* We need to take care for ETIMEDOUT errors here since the
* complete callback does not get called in this case.
* Take care of all errors here and avoid additional code to
* transfer the error value to the complete callback.
*/
if (error) {
blk_mq_end_request(req, error);
blk_mq_run_hw_queues(req->q, true);
} else {
blk_mq_complete_request(req);
}
}
/*
* Process ccw request queue.
*/
static void __dasd_process_block_ccw_queue(struct dasd_block *block,
struct list_head *final_queue)
{
struct list_head *l, *n;
struct dasd_ccw_req *cqr;
dasd_erp_fn_t erp_fn;
unsigned long flags;
struct dasd_device *base = block->base;
restart:
/* Process request with final status. */
list_for_each_safe(l, n, &block->ccw_queue) {
cqr = list_entry(l, struct dasd_ccw_req, blocklist);
if (cqr->status != DASD_CQR_DONE &&
cqr->status != DASD_CQR_FAILED &&
cqr->status != DASD_CQR_NEED_ERP &&
cqr->status != DASD_CQR_TERMINATED)
continue;
if (cqr->status == DASD_CQR_TERMINATED) {
base->discipline->handle_terminated_request(cqr);
goto restart;
}
/* Process requests that may be recovered */
if (cqr->status == DASD_CQR_NEED_ERP) {
erp_fn = base->discipline->erp_action(cqr);
if (IS_ERR(erp_fn(cqr)))
continue;
goto restart;
}
/* log sense for fatal error */
if (cqr->status == DASD_CQR_FAILED) {
dasd_log_sense(cqr, &cqr->irb);
}
/* First of all call extended error reporting. */
if (dasd_eer_enabled(base) &&
cqr->status == DASD_CQR_FAILED) {
dasd_eer_write(base, cqr, DASD_EER_FATALERROR);
/* restart request */
cqr->status = DASD_CQR_FILLED;
cqr->retries = 255;
spin_lock_irqsave(get_ccwdev_lock(base->cdev), flags);
dasd_device_set_stop_bits(base, DASD_STOPPED_QUIESCE);
spin_unlock_irqrestore(get_ccwdev_lock(base->cdev),
flags);
goto restart;
}
/* Process finished ERP request. */
if (cqr->refers) {
__dasd_process_erp(base, cqr);
goto restart;
}
/* Rechain finished requests to final queue */
cqr->endclk = get_tod_clock();
list_move_tail(&cqr->blocklist, final_queue);
}
}
static void dasd_return_cqr_cb(struct dasd_ccw_req *cqr, void *data)
{
dasd_schedule_block_bh(cqr->block);
}
static void __dasd_block_start_head(struct dasd_block *block)
{
struct dasd_ccw_req *cqr;
if (list_empty(&block->ccw_queue))
return;
/* We allways begin with the first requests on the queue, as some
* of previously started requests have to be enqueued on a
* dasd_device again for error recovery.
*/
list_for_each_entry(cqr, &block->ccw_queue, blocklist) {
if (cqr->status != DASD_CQR_FILLED)
continue;
if (test_bit(DASD_FLAG_LOCK_STOLEN, &block->base->flags) &&
!test_bit(DASD_CQR_ALLOW_SLOCK, &cqr->flags)) {
cqr->status = DASD_CQR_FAILED;
cqr->intrc = -EPERM;
dasd_schedule_block_bh(block);
continue;
}
/* Non-temporary stop condition will trigger fail fast */
if (block->base->stopped & ~DASD_STOPPED_PENDING &&
test_bit(DASD_CQR_FLAGS_FAILFAST, &cqr->flags) &&
(!dasd_eer_enabled(block->base))) {
cqr->status = DASD_CQR_FAILED;
cqr->intrc = -ENOLINK;