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linux/drivers/s390/block/dasd.c
Linus Torvalds 85a0b791bc Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux 
Pull s390 updates from Heiko Carstens:
 "Since Martin is on vacation you get the s390 pull request from me:

   - Host large page support for KVM guests. As the patches have large
     impact on arch/s390/mm/ this series goes out via both the KVM and
     the s390 tree.

   - Add an option for no compression to the "Kernel compression mode"
     menu, this will come in handy with the rework of the early boot
     code.

   - A large rework of the early boot code that will make life easier
     for KASAN and KASLR. With the rework the bootable uncompressed
     image is not generated anymore, only the bzImage is available. For
     debuggung purposes the new "no compression" option is used.

   - Re-enable the gcc plugins as the issue with the latent entropy
     plugin is solved with the early boot code rework.

   - More spectre relates changes:
      + Detect the etoken facility and remove expolines automatically.
      + Add expolines to a few more indirect branches.

   - A rewrite of the common I/O layer trace points to make them
     consumable by 'perf stat'.

   - Add support for format-3 PCI function measurement blocks.

   - Changes for the zcrypt driver:
      + Add attributes to indicate the load of cards and queues.
      + Restructure some code for the upcoming AP device support in KVM.

   - Build flags improvements in various Makefiles.

   - A few fixes for the kdump support.

   - A couple of patches for gcc 8 compile warning cleanup.

   - Cleanup s390 specific proc handlers.

   - Add s390 support to the restartable sequence self tests.

   - Some PTR_RET vs PTR_ERR_OR_ZERO cleanup.

   - Lots of bug fixes"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (107 commits)
  s390/dasd: fix hanging offline processing due to canceled worker
  s390/dasd: fix panic for failed online processing
  s390/mm: fix addressing exception after suspend/resume
  rseq/selftests: add s390 support
  s390: fix br_r1_trampoline for machines without exrl
  s390/lib: use expoline for all bcr instructions
  s390/numa: move initial setup of node_to_cpumask_map
  s390/kdump: Fix elfcorehdr size calculation
  s390/cpum_sf: save TOD clock base in SDBs for time conversion
  KVM: s390: Add huge page enablement control
  s390/mm: Add huge page gmap linking support
  s390/mm: hugetlb pages within a gmap can not be freed
  KVM: s390: Add skey emulation fault handling
  s390/mm: Add huge pmd storage key handling
  s390/mm: Clear skeys for newly mapped huge guest pmds
  s390/mm: Clear huge page storage keys on enable_skey
  s390/mm: Add huge page dirty sync support
  s390/mm: Add gmap pmd invalidation and clearing
  s390/mm: Add gmap pmd notification bit setting
  s390/mm: Add gmap pmd linking
  ...
2018-08-13 19:07:17 -07:00

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// 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;
dasd_schedule_block_bh(block);
continue;
}
/* Don't try to start requests if device is stopped */
if (block->base->stopped)
return;
/* just a fail safe check, should not happen */
if (!cqr->startdev)
cqr->startdev = block->base;
/* make sure that the requests we submit find their way back */
cqr->callback = dasd_return_cqr_cb;
dasd_add_request_tail(cqr);
}
}
/*
* Central dasd_block layer routine. Takes requests from the generic
* block layer request queue, creates ccw requests, enqueues them on
* a dasd_device and processes ccw requests that have been returned.
*/
static void dasd_block_tasklet(unsigned long data)
{
struct dasd_block *block = (struct dasd_block *) data;
struct list_head final_queue;
struct list_head *l, *n;
struct dasd_ccw_req *cqr;
struct dasd_queue *dq;
atomic_set(&block->tasklet_scheduled, 0);
INIT_LIST_HEAD(&final_queue);
spin_lock_irq(&block->queue_lock);
/* Finish off requests on ccw queue */
__dasd_process_block_ccw_queue(block, &final_queue);
spin_unlock_irq(&block->queue_lock);
/* Now call the callback function of requests with final status */
list_for_each_safe(l, n, &final_queue) {
cqr = list_entry(l, struct dasd_ccw_req, blocklist);
dq = cqr->dq;
spin_lock_irq(&dq->lock);
list_del_init(&cqr->blocklist);
__dasd_cleanup_cqr(cqr);
spin_unlock_irq(&dq->lock);
}
spin_lock_irq(&block->queue_lock);
/* Now check if the head of the ccw queue needs to be started. */
__dasd_block_start_head(block);
spin_unlock_irq(&block->queue_lock);
if (waitqueue_active(&shutdown_waitq))
wake_up(&shutdown_waitq);
dasd_put_device(block->base);
}
static void _dasd_wake_block_flush_cb(struct dasd_ccw_req *cqr, void *data)
{
wake_up(&dasd_flush_wq);
}
/*
* Requeue a request back to the block request queue
* only works for block requests
*/
static int _dasd_requeue_request(struct dasd_ccw_req *cqr)
{
struct dasd_block *block = cqr->block;
struct request *req;
if (!block)
return -EINVAL;
spin_lock_irq(&cqr->dq->lock);
req = (struct request *) cqr->callback_data;
blk_mq_requeue_request(req, false);
spin_unlock_irq(&cqr->dq->lock);
return 0;
}
/*
* Go through all request on the dasd_block request queue, cancel them
* on the respective dasd_device, and return them to the generic
* block layer.
*/
static int dasd_flush_block_queue(struct dasd_block *block)
{
struct dasd_ccw_req *cqr, *n;
int rc, i;
struct list_head flush_queue;
unsigned long flags;
INIT_LIST_HEAD(&flush_queue);
spin_lock_bh(&block->queue_lock);
rc = 0;
restart:
list_for_each_entry_safe(cqr, n, &block->ccw_queue, blocklist) {
/* if this request currently owned by a dasd_device cancel it */
if (cqr->status >= DASD_CQR_QUEUED)
rc = dasd_cancel_req(cqr);
if (rc < 0)
break;
/* Rechain request (including erp chain) so it won't be
* touched by the dasd_block_tasklet anymore.
* Replace the callback so we notice when the request
* is returned from the dasd_device layer.
*/
cqr->callback = _dasd_wake_block_flush_cb;
for (i = 0; cqr != NULL; cqr = cqr->refers, i++)
list_move_tail(&cqr->blocklist, &flush_queue);
if (i > 1)
/* moved more than one request - need to restart */
goto restart;
}
spin_unlock_bh(&block->queue_lock);
/* Now call the callback function of flushed requests */
restart_cb:
list_for_each_entry_safe(cqr, n, &flush_queue, blocklist) {
wait_event(dasd_flush_wq, (cqr->status < DASD_CQR_QUEUED));
/* Process finished ERP request. */
if (cqr->refers) {
spin_lock_bh(&block->queue_lock);
__dasd_process_erp(block->base, cqr);
spin_unlock_bh(&block->queue_lock);
/* restart list_for_xx loop since dasd_process_erp
* might remove multiple elements */
goto restart_cb;
}
/* call the callback function */
spin_lock_irqsave(&cqr->dq->lock, flags);
cqr->endclk = get_tod_clock();
list_del_init(&cqr->blocklist);
__dasd_cleanup_cqr(cqr);
spin_unlock_irqrestore(&cqr->dq->lock, flags);
}
return rc;
}
/*
* Schedules a call to dasd_tasklet over the device tasklet.
*/
void dasd_schedule_block_bh(struct dasd_block *block)
{
/* Protect against rescheduling. */
if (atomic_cmpxchg(&block->tasklet_scheduled, 0, 1) != 0)
return;
/* life cycle of block is bound to it's base device */
dasd_get_device(block->base);
tasklet_hi_schedule(&block->tasklet);
}
EXPORT_SYMBOL(dasd_schedule_block_bh);
/*
* SECTION: external block device operations
* (request queue handling, open, release, etc.)
*/
/*
* Dasd request queue function. Called from ll_rw_blk.c
*/
static blk_status_t do_dasd_request(struct blk_mq_hw_ctx *hctx,
const struct blk_mq_queue_data *qd)
{
struct dasd_block *block = hctx->queue->queuedata;
struct dasd_queue *dq = hctx->driver_data;
struct request *req = qd->rq;
struct dasd_device *basedev;
struct dasd_ccw_req *cqr;
blk_status_t rc = BLK_STS_OK;
basedev = block->base;
spin_lock_irq(&dq->lock);
if (basedev->state < DASD_STATE_READY) {
DBF_DEV_EVENT(DBF_ERR, basedev,
"device not ready for request %p", req);
rc = BLK_STS_IOERR;
goto out;
}
/*
* if device is stopped do not fetch new requests
* except failfast is active which will let requests fail
* immediately in __dasd_block_start_head()
*/
if (basedev->stopped && !(basedev->features & DASD_FEATURE_FAILFAST)) {
DBF_DEV_EVENT(DBF_ERR, basedev,
"device stopped request %p", req);
rc = BLK_STS_RESOURCE;
goto out;
}
if (basedev->features & DASD_FEATURE_READONLY &&
rq_data_dir(req) == WRITE) {
DBF_DEV_EVENT(DBF_ERR, basedev,
"Rejecting write request %p", req);
rc = BLK_STS_IOERR;
goto out;
}
if (test_bit(DASD_FLAG_ABORTALL, &basedev->flags) &&
(basedev->features & DASD_FEATURE_FAILFAST ||
blk_noretry_request(req))) {
DBF_DEV_EVENT(DBF_ERR, basedev,
"Rejecting failfast request %p", req);
rc = BLK_STS_IOERR;
goto out;
}
cqr = basedev->discipline->build_cp(basedev, block, req);
if (IS_ERR(cqr)) {
if (PTR_ERR(cqr) == -EBUSY ||
PTR_ERR(cqr) == -ENOMEM ||
PTR_ERR(cqr) == -EAGAIN) {
rc = BLK_STS_RESOURCE;
goto out;
}
DBF_DEV_EVENT(DBF_ERR, basedev,
"CCW creation failed (rc=%ld) on request %p",
PTR_ERR(cqr), req);
rc = BLK_STS_IOERR;
goto out;
}
/*
* Note: callback is set to dasd_return_cqr_cb in
* __dasd_block_start_head to cover erp requests as well
*/
cqr->callback_data = req;
cqr->status = DASD_CQR_FILLED;
cqr->dq = dq;
blk_mq_start_request(req);
spin_lock(&block->queue_lock);
list_add_tail(&cqr->blocklist, &block->ccw_queue);
INIT_LIST_HEAD(&cqr->devlist);
dasd_profile_start(block, cqr, req);
dasd_schedule_block_bh(block);
spin_unlock(&block->queue_lock);
out:
spin_unlock_irq(&dq->lock);
return rc;
}
/*
* Block timeout callback, called from the block layer
*
* Return values:
* BLK_EH_RESET_TIMER if the request should be left running
* BLK_EH_DONE if the request is handled or terminated
* by the driver.
*/
enum blk_eh_timer_return dasd_times_out(struct request *req, bool reserved)
{
struct dasd_block *block = req->q->queuedata;
struct dasd_device *device;
struct dasd_ccw_req *cqr;
unsigned long flags;
int rc = 0;
cqr = blk_mq_rq_to_pdu(req);
if (!cqr)
return BLK_EH_DONE;
spin_lock_irqsave(&cqr->dq->lock, flags);
device = cqr->startdev ? cqr->startdev : block->base;
if (!device->blk_timeout) {
spin_unlock_irqrestore(&cqr->dq->lock, flags);
return BLK_EH_RESET_TIMER;
}
DBF_DEV_EVENT(DBF_WARNING, device,
" dasd_times_out cqr %p status %x",
cqr, cqr->status);
spin_lock(&block->queue_lock);
spin_lock(get_ccwdev_lock(device->cdev));
cqr->retries = -1;
cqr->intrc = -ETIMEDOUT;
if (cqr->status >= DASD_CQR_QUEUED) {
rc = __dasd_cancel_req(cqr);
} else if (cqr->status == DASD_CQR_FILLED ||
cqr->status == DASD_CQR_NEED_ERP) {
cqr->status = DASD_CQR_TERMINATED;
} else if (cqr->status == DASD_CQR_IN_ERP) {
struct dasd_ccw_req *searchcqr, *nextcqr, *tmpcqr;
list_for_each_entry_safe(searchcqr, nextcqr,
&block->ccw_queue, blocklist) {
tmpcqr = searchcqr;
while (tmpcqr->refers)
tmpcqr = tmpcqr->refers;
if (tmpcqr != cqr)
continue;
/* searchcqr is an ERP request for cqr */
searchcqr->retries = -1;
searchcqr->intrc = -ETIMEDOUT;
if (searchcqr->status >= DASD_CQR_QUEUED) {
rc = __dasd_cancel_req(searchcqr);
} else if ((searchcqr->status == DASD_CQR_FILLED) ||
(searchcqr->status == DASD_CQR_NEED_ERP)) {
searchcqr->status = DASD_CQR_TERMINATED;
rc = 0;
} else if (searchcqr->status == DASD_CQR_IN_ERP) {
/*
* Shouldn't happen; most recent ERP
* request is at the front of queue
*/
continue;
}
break;
}
}
spin_unlock(get_ccwdev_lock(device->cdev));
dasd_schedule_block_bh(block);
spin_unlock(&block->queue_lock);
spin_unlock_irqrestore(&cqr->dq->lock, flags);
return rc ? BLK_EH_RESET_TIMER : BLK_EH_DONE;
}
static int dasd_init_hctx(struct blk_mq_hw_ctx *hctx, void *data,
unsigned int idx)
{
struct dasd_queue *dq = kzalloc(sizeof(*dq), GFP_KERNEL);
if (!dq)
return -ENOMEM;
spin_lock_init(&dq->lock);
hctx->driver_data = dq;
return 0;
}
static void dasd_exit_hctx(struct blk_mq_hw_ctx *hctx, unsigned int idx)
{
kfree(hctx->driver_data);
hctx->driver_data = NULL;
}
static void dasd_request_done(struct request *req)
{
blk_mq_end_request(req, 0);
blk_mq_run_hw_queues(req->q, true);
}
static struct blk_mq_ops dasd_mq_ops = {
.queue_rq = do_dasd_request,
.complete = dasd_request_done,
.timeout = dasd_times_out,
.init_hctx = dasd_init_hctx,
.exit_hctx = dasd_exit_hctx,
};
/*
* Allocate and initialize request queue and default I/O scheduler.
*/
static int dasd_alloc_queue(struct dasd_block *block)
{
int rc;
block->tag_set.ops = &dasd_mq_ops;
block->tag_set.cmd_size = sizeof(struct dasd_ccw_req);
block->tag_set.nr_hw_queues = nr_hw_queues;
block->tag_set.queue_depth = queue_depth;
block->tag_set.flags = BLK_MQ_F_SHOULD_MERGE;
block->tag_set.numa_node = NUMA_NO_NODE;
rc = blk_mq_alloc_tag_set(&block->tag_set);
if (rc)
return rc;
block->request_queue = blk_mq_init_queue(&block->tag_set);
if (IS_ERR(block->request_queue))
return PTR_ERR(block->request_queue);
block->request_queue->queuedata = block;
return 0;
}
/*
* Allocate and initialize request queue.
*/
static void dasd_setup_queue(struct dasd_block *block)
{
unsigned int logical_block_size = block->bp_block;
struct request_queue *q = block->request_queue;
unsigned int max_bytes, max_discard_sectors;
int max;
if (block->base->features & DASD_FEATURE_USERAW) {
/*
* the max_blocks value for raw_track access is 256
* it is higher than the native ECKD value because we
* only need one ccw per track
* so the max_hw_sectors are
* 2048 x 512B = 1024kB = 16 tracks
*/
max = 2048;
} else {
max = block->base->discipline->max_blocks << block->s2b_shift;
}
blk_queue_flag_set(QUEUE_FLAG_NONROT, q);
q->limits.max_dev_sectors = max;
blk_queue_logical_block_size(q, logical_block_size);
blk_queue_max_hw_sectors(q, max);
blk_queue_max_segments(q, USHRT_MAX);
/* with page sized segments we can translate each segement into
* one idaw/tidaw
*/
blk_queue_max_segment_size(q, PAGE_SIZE);
blk_queue_segment_boundary(q, PAGE_SIZE - 1);
/* Only activate blocklayer discard support for devices that support it */
if (block->base->features & DASD_FEATURE_DISCARD) {
q->limits.discard_granularity = logical_block_size;
q->limits.discard_alignment = PAGE_SIZE;
/* Calculate max_discard_sectors and make it PAGE aligned */
max_bytes = USHRT_MAX * logical_block_size;
max_bytes = ALIGN(max_bytes, PAGE_SIZE) - PAGE_SIZE;
max_discard_sectors = max_bytes / logical_block_size;
blk_queue_max_discard_sectors(q, max_discard_sectors);
blk_queue_max_write_zeroes_sectors(q, max_discard_sectors);
blk_queue_flag_set(QUEUE_FLAG_DISCARD, q);
}
}
/*
* Deactivate and free request queue.
*/
static void dasd_free_queue(struct dasd_block *block)
{
if (block->request_queue) {
blk_cleanup_queue(block->request_queue);
blk_mq_free_tag_set(&block->tag_set);
block->request_queue = NULL;
}
}
static int dasd_open(struct block_device *bdev, fmode_t mode)
{
struct dasd_device *base;
int rc;
base = dasd_device_from_gendisk(bdev->bd_disk);
if (!base)
return -ENODEV;
atomic_inc(&base->block->open_count);
if (test_bit(DASD_FLAG_OFFLINE, &base->flags)) {
rc = -ENODEV;
goto unlock;
}
if (!try_module_get(base->discipline->owner)) {
rc = -EINVAL;
goto unlock;
}
if (dasd_probeonly) {
dev_info(&base->cdev->dev,
"Accessing the DASD failed because it is in "
"probeonly mode\n");
rc = -EPERM;
goto out;
}
if (base->state <= DASD_STATE_BASIC) {
DBF_DEV_EVENT(DBF_ERR, base, " %s",
" Cannot open unrecognized device");
rc = -ENODEV;
goto out;
}
if ((mode & FMODE_WRITE) &&
(test_bit(DASD_FLAG_DEVICE_RO, &base->flags) ||
(base->features & DASD_FEATURE_READONLY))) {
rc = -EROFS;
goto out;
}
dasd_put_device(base);
return 0;
out:
module_put(base->discipline->owner);
unlock:
atomic_dec(&base->block->open_count);
dasd_put_device(base);
return rc;
}
static void dasd_release(struct gendisk *disk, fmode_t mode)
{
struct dasd_device *base = dasd_device_from_gendisk(disk);
if (base) {
atomic_dec(&base->block->open_count);
module_put(base->discipline->owner);
dasd_put_device(base);
}
}
/*
* Return disk geometry.
*/
static int dasd_getgeo(struct block_device *bdev, struct hd_geometry *geo)
{
struct dasd_device *base;
base = dasd_device_from_gendisk(bdev->bd_disk);
if (!base)
return -ENODEV;
if (!base->discipline ||
!base->discipline->fill_geometry) {
dasd_put_device(base);
return -EINVAL;
}
base->discipline->fill_geometry(base->block, geo);
geo->start = get_start_sect(bdev) >> base->block->s2b_shift;
dasd_put_device(base);
return 0;
}
const struct block_device_operations
dasd_device_operations = {
.owner = THIS_MODULE,
.open = dasd_open,
.release = dasd_release,
.ioctl = dasd_ioctl,
.compat_ioctl = dasd_ioctl,
.getgeo = dasd_getgeo,
};
/*******************************************************************************
* end of block device operations
*/
static void
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;
}
dasd_gendisk_exit();
dasd_devmap_exit();
if (dasd_debug_area != NULL) {
debug_unregister(dasd_debug_area);
dasd_debug_area = NULL;
}
dasd_statistics_removeroot();
}
/*
* SECTION: common functions for ccw_driver use
*/
/*
* Is the device read-only?
* Note that this function does not report the setting of the
* readonly device attribute, but how it is configured in z/VM.
*/
int dasd_device_is_ro(struct dasd_device *device)
{
struct ccw_dev_id dev_id;
struct diag210 diag_data;
int rc;
if (!MACHINE_IS_VM)
return 0;
ccw_device_get_id(device->cdev, &dev_id);
memset(&diag_data, 0, sizeof(diag_data));
diag_data.vrdcdvno = dev_id.devno;
diag_data.vrdclen = sizeof(diag_data);
rc = diag210(&diag_data);
if (rc == 0 || rc == 2) {
return diag_data.vrdcvfla & 0x80;
} else {
DBF_EVENT(DBF_WARNING, "diag210 failed for dev=%04x with rc=%d",
dev_id.devno, rc);
return 0;
}
}
EXPORT_SYMBOL_GPL(dasd_device_is_ro);
static void dasd_generic_auto_online(void *data, async_cookie_t cookie)
{
struct ccw_device *cdev = data;
int ret;
ret = ccw_device_set_online(cdev);
if (ret)
pr_warn("%s: Setting the DASD online failed with rc=%d\n",
dev_name(&cdev->dev), ret);
}
/*
* Initial attempt at a probe function. this can be simplified once
* the other detection code is gone.
*/
int dasd_generic_probe(struct ccw_device *cdev,
struct dasd_discipline *discipline)
{
int ret;
ret = dasd_add_sysfs_files(cdev);
if (ret) {
DBF_EVENT_DEVID(DBF_WARNING, cdev, "%s",
"dasd_generic_probe: could not add "
"sysfs entries");
return ret;
}
cdev->handler = &dasd_int_handler;
/*
* Automatically online either all dasd devices (dasd_autodetect)
* or all devices specified with dasd= parameters during
* initial probe.
*/
if ((dasd_get_feature(cdev, DASD_FEATURE_INITIAL_ONLINE) > 0 ) ||
(dasd_autodetect && dasd_busid_known(dev_name(&cdev->dev)) != 0))
async_schedule(dasd_generic_auto_online, cdev);
return 0;
}
EXPORT_SYMBOL_GPL(dasd_generic_probe);
void dasd_generic_free_discipline(struct dasd_device *device)
{
/* Forget the discipline information. */
if (device->discipline) {
if (device->discipline->uncheck_device)
device->discipline->uncheck_device(device);
module_put(device->discipline->owner);
device->discipline = NULL;
}
if (device->base_discipline) {
module_put(device->base_discipline->owner);
device->base_discipline = NULL;
}
}
EXPORT_SYMBOL_GPL(dasd_generic_free_discipline);
/*
* This will one day be called from a global not_oper handler.
* It is also used by driver_unregister during module unload.
*/
void dasd_generic_remove(struct ccw_device *cdev)
{
struct dasd_device *device;
struct dasd_block *block;
cdev->handler = NULL;
device = dasd_device_from_cdev(cdev);
if (IS_ERR(device)) {
dasd_remove_sysfs_files(cdev);
return;
}
if (test_and_set_bit(DASD_FLAG_OFFLINE, &device->flags) &&
!test_bit(DASD_FLAG_SAFE_OFFLINE_RUNNING, &device->flags)) {
/* Already doing offline processing */
dasd_put_device(device);
dasd_remove_sysfs_files(cdev);
return;
}
/*
* This device is removed unconditionally. Set offline
* flag to prevent dasd_open from opening it while it is
* no quite down yet.
*/
dasd_set_target_state(device, DASD_STATE_NEW);
/* dasd_delete_device destroys the device reference. */
block = device->block;
dasd_delete_device(device);
/*
* life cycle of block is bound to device, so delete it after
* device was safely removed
*/
if (block)
dasd_free_block(block);
dasd_remove_sysfs_files(cdev);
}
EXPORT_SYMBOL_GPL(dasd_generic_remove);
/*
* Activate a device. This is called from dasd_{eckd,fba}_probe() when either
* the device is detected for the first time and is supposed to be used
* or the user has started activation through sysfs.
*/
int dasd_generic_set_online(struct ccw_device *cdev,
struct dasd_discipline *base_discipline)
{
struct dasd_discipline *discipline;
struct dasd_device *device;
int rc;
/* first online clears initial online feature flag */
dasd_set_feature(cdev, DASD_FEATURE_INITIAL_ONLINE, 0);
device = dasd_create_device(cdev);
if (IS_ERR(device))
return PTR_ERR(device);
discipline = base_discipline;
if (device->features & DASD_FEATURE_USEDIAG) {
if (!dasd_diag_discipline_pointer) {
/* Try to load the required module. */
rc = request_module(DASD_DIAG_MOD);
if (rc) {
pr_warn("%s Setting the DASD online failed "
"because the required module %s "
"could not be loaded (rc=%d)\n",
dev_name(&cdev->dev), DASD_DIAG_MOD,
rc);
dasd_delete_device(device);
return -ENODEV;
}
}
/* Module init could have failed, so check again here after
* request_module(). */
if (!dasd_diag_discipline_pointer) {
pr_warn("%s Setting the DASD online failed because of missing DIAG discipline\n",
dev_name(&cdev->dev));
dasd_delete_device(device);
return -ENODEV;
}
discipline = dasd_diag_discipline_pointer;
}
if (!try_module_get(base_discipline->owner)) {
dasd_delete_device(device);
return -EINVAL;
}
if (!try_module_get(discipline->owner)) {
module_put(base_discipline->owner);
dasd_delete_device(device);
return -EINVAL;
}
device->base_discipline = base_discipline;
device->discipline = discipline;
/* check_device will allocate block device if necessary */
rc = discipline->check_device(device);
if (rc) {
pr_warn("%s Setting the DASD online with discipline %s failed with rc=%i\n",
dev_name(&cdev->dev), discipline->name, rc);
module_put(discipline->owner);
module_put(base_discipline->owner);
dasd_delete_device(device);
return rc;
}
dasd_set_target_state(device, DASD_STATE_ONLINE);
if (device->state <= DASD_STATE_KNOWN) {
pr_warn("%s Setting the DASD online failed because of a missing discipline\n",
dev_name(&cdev->dev));
rc = -ENODEV;
dasd_set_target_state(device, DASD_STATE_NEW);
if (device->block)
dasd_free_block(device->block);
dasd_delete_device(device);
} else
pr_debug("dasd_generic device %s found\n",
dev_name(&cdev->dev));
wait_event(dasd_init_waitq, _wait_for_device(device));
dasd_put_device(device);
return rc;
}
EXPORT_SYMBOL_GPL(dasd_generic_set_online);
int dasd_generic_set_offline(struct ccw_device *cdev)
{
struct dasd_device *device;
struct dasd_block *block;
int max_count, open_count, rc;
unsigned long flags;
rc = 0;
spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
device = dasd_device_from_cdev_locked(cdev);
if (IS_ERR(device)) {
spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
return PTR_ERR(device);
}
/*
* We must make sure that this device is currently not in use.
* The open_count is increased for every opener, that includes
* the blkdev_get in dasd_scan_partitions. We are only interested
* in the other openers.
*/
if (device->block) {
max_count = device->block->bdev ? 0 : -1;
open_count = atomic_read(&device->block->open_count);
if (open_count > max_count) {
if (open_count > 0)
pr_warn("%s: The DASD cannot be set offline with open count %i\n",
dev_name(&cdev->dev), open_count);
else
pr_warn("%s: The DASD cannot be set offline while it is in use\n",
dev_name(&cdev->dev));
rc = -EBUSY;
goto out_err;
}
}
/*
* Test if the offline processing is already running and exit if so.
* If a safe offline is being processed this could only be a normal
* offline that should be able to overtake the safe offline and
* cancel any I/O we do not want to wait for any longer
*/
if (test_bit(DASD_FLAG_OFFLINE, &device->flags)) {
if (test_bit(DASD_FLAG_SAFE_OFFLINE_RUNNING, &device->flags)) {
clear_bit(DASD_FLAG_SAFE_OFFLINE_RUNNING,
&device->flags);
} else {
rc = -EBUSY;
goto out_err;
}
}
set_bit(DASD_FLAG_OFFLINE, &device->flags);
/*
* if safe_offline is called set safe_offline_running flag and
* clear safe_offline so that a call to normal offline
* can overrun safe_offline processing
*/
if (test_and_clear_bit(DASD_FLAG_SAFE_OFFLINE, &device->flags) &&
!test_and_set_bit(DASD_FLAG_SAFE_OFFLINE_RUNNING, &device->flags)) {
/* need to unlock here to wait for outstanding I/O */
spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
/*
* If we want to set the device safe offline all IO operations
* should be finished before continuing the offline process
* so sync bdev first and then wait for our queues to become
* empty
*/
if (device->block) {
rc = fsync_bdev(device->block->bdev);
if (rc != 0)
goto interrupted;
}
dasd_schedule_device_bh(device);
rc = wait_event_interruptible(shutdown_waitq,
_wait_for_empty_queues(device));
if (rc != 0)
goto interrupted;
/*
* check if a normal offline process overtook the offline
* processing in this case simply do nothing beside returning
* that we got interrupted
* otherwise mark safe offline as not running any longer and
* continue with normal offline
*/
spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
if (!test_bit(DASD_FLAG_SAFE_OFFLINE_RUNNING, &device->flags)) {
rc = -ERESTARTSYS;
goto out_err;
}
clear_bit(DASD_FLAG_SAFE_OFFLINE_RUNNING, &device->flags);
}
spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
dasd_set_target_state(device, DASD_STATE_NEW);
/* dasd_delete_device destroys the device reference. */
block = device->block;
dasd_delete_device(device);
/*
* life cycle of block is bound to device, so delete it after
* device was safely removed
*/
if (block)
dasd_free_block(block);
return 0;
interrupted:
/* interrupted by signal */
spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
clear_bit(DASD_FLAG_SAFE_OFFLINE_RUNNING, &device->flags);
clear_bit(DASD_FLAG_OFFLINE, &device->flags);
out_err:
dasd_put_device(device);
spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
return rc;
}
EXPORT_SYMBOL_GPL(dasd_generic_set_offline);
int dasd_generic_last_path_gone(struct dasd_device *device)
{
struct dasd_ccw_req *cqr;
dev_warn(&device->cdev->dev, "No operational channel path is left "
"for the device\n");
DBF_DEV_EVENT(DBF_WARNING, device, "%s", "last path gone");
/* First of all call extended error reporting. */
dasd_eer_write(device, NULL, DASD_EER_NOPATH);
if (device->state < DASD_STATE_BASIC)
return 0;
/* Device is active. We want to keep it. */
list_for_each_entry(cqr, &device->ccw_queue, devlist)
if ((cqr->status == DASD_CQR_IN_IO) ||
(cqr->status == DASD_CQR_CLEAR_PENDING)) {
cqr->status = DASD_CQR_QUEUED;
cqr->retries++;
}
dasd_device_set_stop_bits(device, DASD_STOPPED_DC_WAIT);
dasd_device_clear_timer(device);
dasd_schedule_device_bh(device);
return 1;
}
EXPORT_SYMBOL_GPL(dasd_generic_last_path_gone);
int dasd_generic_path_operational(struct dasd_device *device)
{
dev_info(&device->cdev->dev, "A channel path to the device has become "
"operational\n");
DBF_DEV_EVENT(DBF_WARNING, device, "%s", "path operational");
dasd_device_remove_stop_bits(device, DASD_STOPPED_DC_WAIT);
if (device->stopped & DASD_UNRESUMED_PM) {
dasd_device_remove_stop_bits(device, DASD_UNRESUMED_PM);
dasd_restore_device(device);
return 1;
}
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);
}
if (!device->stopped)
wake_up(&generic_waitq);
return 1;
}
EXPORT_SYMBOL_GPL(dasd_generic_path_operational);
int dasd_generic_notify(struct ccw_device *cdev, int event)
{
struct dasd_device *device;
int ret;
device = dasd_device_from_cdev_locked(cdev);
if (IS_ERR(device))
return 0;
ret = 0;
switch (event) {
case CIO_GONE:
case CIO_BOXED:
case CIO_NO_PATH:
dasd_path_no_path(device);
ret = dasd_generic_last_path_gone(device);
break;
case CIO_OPER:
ret = 1;
if (dasd_path_get_opm(device))
ret = dasd_generic_path_operational(device);
break;
}
dasd_put_device(device);
return ret;
}
EXPORT_SYMBOL_GPL(dasd_generic_notify);
void dasd_generic_path_event(struct ccw_device *cdev, int *path_event)
{
struct dasd_device *device;
int chp, oldopm, hpfpm, ifccpm;
device = dasd_device_from_cdev_locked(cdev);
if (IS_ERR(device))
return;
oldopm = dasd_path_get_opm(device);
for (chp = 0; chp < 8; chp++) {
if (path_event[chp] & PE_PATH_GONE) {
dasd_path_notoper(device, chp);
}
if (path_event[chp] & PE_PATH_AVAILABLE) {
dasd_path_available(device, chp);
dasd_schedule_device_bh(device);
}
if (path_event[chp] & PE_PATHGROUP_ESTABLISHED) {
if (!dasd_path_is_operational(device, chp) &&
!dasd_path_need_verify(device, chp)) {
/*
* we can not establish a pathgroup on an
* unavailable path, so trigger a path
* verification first
*/
dasd_path_available(device, chp);
dasd_schedule_device_bh(device);
}
DBF_DEV_EVENT(DBF_WARNING, device, "%s",
"Pathgroup re-established\n");
if (device->discipline->kick_validate)
device->discipline->kick_validate(device);
}
}
hpfpm = dasd_path_get_hpfpm(device);
ifccpm = dasd_path_get_ifccpm(device);
if (!dasd_path_get_opm(device) && hpfpm) {
/*
* device has no operational paths but at least one path is
* disabled due to HPF errors
* disable HPF at all and use the path(s) again
*/
if (device->discipline->disable_hpf)
device->discipline->disable_hpf(device);
dasd_device_set_stop_bits(device, DASD_STOPPED_NOT_ACC);
dasd_path_set_tbvpm(device, hpfpm);
dasd_schedule_device_bh(device);
dasd_schedule_requeue(device);
} else if (!dasd_path_get_opm(device) && ifccpm) {
/*
* device has no operational paths but at least one path is
* disabled due to IFCC errors
* trigger path verification on paths with IFCC errors
*/
dasd_path_set_tbvpm(device, ifccpm);
dasd_schedule_device_bh(device);
}
if (oldopm && !dasd_path_get_opm(device) && !hpfpm && !ifccpm) {
dev_warn(&device->cdev->dev,
"No verified channel paths remain for the device\n");
DBF_DEV_EVENT(DBF_WARNING, device,
"%s", "last verified path gone");
dasd_eer_write(device, NULL, DASD_EER_NOPATH);
dasd_device_set_stop_bits(device,
DASD_STOPPED_DC_WAIT);
}
dasd_put_device(device);
}
EXPORT_SYMBOL_GPL(dasd_generic_path_event);
int dasd_generic_verify_path(struct dasd_device *device, __u8 lpm)
{
if (!dasd_path_get_opm(device) && lpm) {
dasd_path_set_opm(device, lpm);
dasd_generic_path_operational(device);
} else
dasd_path_add_opm(device, lpm);
return 0;
}
EXPORT_SYMBOL_GPL(dasd_generic_verify_path);
/*
* clear active requests and requeue them to block layer if possible
*/
static int dasd_generic_requeue_all_requests(struct dasd_device *device)
{
struct list_head requeue_queue;
struct dasd_ccw_req *cqr, *n;
struct dasd_ccw_req *refers;
int rc;
INIT_LIST_HEAD(&requeue_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 */
if (cqr->status == DASD_CQR_IN_IO) {
rc = device->discipline->term_IO(cqr);
if (rc) {
/* unable to terminate requeust */
dev_err(&device->cdev->dev,
"Unable to terminate request %p "
"on suspend\n", cqr);
spin_unlock_irq(get_ccwdev_lock(device->cdev));
dasd_put_device(device);
return rc;
}
}
list_move_tail(&cqr->devlist, &requeue_queue);
}
spin_unlock_irq(get_ccwdev_lock(device->cdev));
list_for_each_entry_safe(cqr, n, &requeue_queue, devlist) {
wait_event(dasd_flush_wq,
(cqr->status != DASD_CQR_CLEAR_PENDING));
/*
* requeue requests to blocklayer will only work
* for block device requests
*/
if (_dasd_requeue_request(cqr))
continue;
/* remove requests from device and block queue */
list_del_init(&cqr->devlist);
while (cqr->refers != NULL) {
refers = cqr->refers;
/* remove the request from the block queue */
list_del(&cqr->blocklist);
/* free the finished erp request */
dasd_free_erp_request(cqr, cqr->memdev);
cqr = refers;
}
/*
* _dasd_requeue_request already checked for a valid
* blockdevice, no need to check again
* all erp requests (cqr->refers) have a cqr->block
* pointer copy from the original cqr
*/
list_del_init(&cqr->blocklist);
cqr->block->base->discipline->free_cp(
cqr, (struct request *) cqr->callback_data);
}
/*
* if requests remain then they are internal request
* and go back to the device queue
*/
if (!list_empty(&requeue_queue)) {
/* move freeze_queue to start of the ccw_queue */
spin_lock_irq(get_ccwdev_lock(device->cdev));
list_splice_tail(&requeue_queue, &device->ccw_queue);
spin_unlock_irq(get_ccwdev_lock(device->cdev));
}
dasd_schedule_device_bh(device);
return rc;
}
static void do_requeue_requests(struct work_struct *work)
{
struct dasd_device *device = container_of(work, struct dasd_device,
requeue_requests);
dasd_generic_requeue_all_requests(device);
dasd_device_remove_stop_bits(device, DASD_STOPPED_NOT_ACC);
if (device->block)
dasd_schedule_block_bh(device->block);
dasd_put_device(device);
}
void dasd_schedule_requeue(struct dasd_device *device)
{
dasd_get_device(device);
/* queue call to dasd_reload_device to the kernel event daemon. */
if (!schedule_work(&device->requeue_requests))
dasd_put_device(device);
}
EXPORT_SYMBOL(dasd_schedule_requeue);
int dasd_generic_pm_freeze(struct ccw_device *cdev)
{
struct dasd_device *device = dasd_device_from_cdev(cdev);
if (IS_ERR(device))
return PTR_ERR(device);
/* mark device as suspended */
set_bit(DASD_FLAG_SUSPENDED, &device->flags);
if (device->discipline->freeze)
device->discipline->freeze(device);
/* disallow new I/O */
dasd_device_set_stop_bits(device, DASD_STOPPED_PM);
return dasd_generic_requeue_all_requests(device);
}
EXPORT_SYMBOL_GPL(dasd_generic_pm_freeze);
int dasd_generic_restore_device(struct ccw_device *cdev)
{
struct dasd_device *device = dasd_device_from_cdev(cdev);
int rc = 0;
if (IS_ERR(device))
return PTR_ERR(device);
/* allow new IO again */
dasd_device_remove_stop_bits(device,
(DASD_STOPPED_PM | DASD_UNRESUMED_PM));
dasd_schedule_device_bh(device);
/*
* call discipline restore function
* if device is stopped do nothing e.g. for disconnected devices
*/
if (device->discipline->restore && !(device->stopped))
rc = device->discipline->restore(device);
if (rc || device->stopped)
/*
* if the resume failed for the DASD we put it in
* an UNRESUMED stop state
*/
device->stopped |= DASD_UNRESUMED_PM;
if (device->block) {
dasd_schedule_block_bh(device->block);
if (device->block->request_queue)
blk_mq_run_hw_queues(device->block->request_queue,
true);
}
clear_bit(DASD_FLAG_SUSPENDED, &device->flags);
dasd_put_device(device);
return 0;
}
EXPORT_SYMBOL_GPL(dasd_generic_restore_device);
static struct dasd_ccw_req *dasd_generic_build_rdc(struct dasd_device *device,
void *rdc_buffer,
int rdc_buffer_size,
int magic)
{
struct dasd_ccw_req *cqr;
struct ccw1 *ccw;
unsigned long *idaw;
cqr = dasd_smalloc_request(magic, 1 /* RDC */, rdc_buffer_size, device,
NULL);
if (IS_ERR(cqr)) {
/* internal error 13 - Allocating the RDC request failed*/
dev_err(&device->cdev->dev,
"An error occurred in the DASD device driver, "
"reason=%s\n", "13");
return cqr;
}
ccw = cqr->cpaddr;
ccw->cmd_code = CCW_CMD_RDC;
if (idal_is_needed(rdc_buffer, rdc_buffer_size)) {
idaw = (unsigned long *) (cqr->data);
ccw->cda = (__u32)(addr_t) idaw;
ccw->flags = CCW_FLAG_IDA;
idaw = idal_create_words(idaw, rdc_buffer, rdc_buffer_size);
} else {
ccw->cda = (__u32)(addr_t) rdc_buffer;
ccw->flags = 0;
}
ccw->count = rdc_buffer_size;
cqr->startdev = device;
cqr->memdev = device;
cqr->expires = 10*HZ;
cqr->retries = 256;
cqr->buildclk = get_tod_clock();
cqr->status = DASD_CQR_FILLED;
return cqr;
}
int dasd_generic_read_dev_chars(struct dasd_device *device, int magic,
void *rdc_buffer, int rdc_buffer_size)
{
int ret;
struct dasd_ccw_req *cqr;
cqr = dasd_generic_build_rdc(device, rdc_buffer, rdc_buffer_size,
magic);
if (IS_ERR(cqr))
return PTR_ERR(cqr);
ret = dasd_sleep_on(cqr);
dasd_sfree_request(cqr, cqr->memdev);
return ret;
}
EXPORT_SYMBOL_GPL(dasd_generic_read_dev_chars);
/*
* In command mode and transport mode we need to look for sense
* data in different places. The sense data itself is allways
* an array of 32 bytes, so we can unify the sense data access
* for both modes.
*/
char *dasd_get_sense(struct irb *irb)
{
struct tsb *tsb = NULL;
char *sense = NULL;
if (scsw_is_tm(&irb->scsw) && (irb->scsw.tm.fcxs == 0x01)) {
if (irb->scsw.tm.tcw)
tsb = tcw_get_tsb((struct tcw *)(unsigned long)
irb->scsw.tm.tcw);
if (tsb && tsb->length == 64 && tsb->flags)
switch (tsb->flags & 0x07) {
case 1: /* tsa_iostat */
sense = tsb->tsa.iostat.sense;
break;
case 2: /* tsa_ddpc */
sense = tsb->tsa.ddpc.sense;
break;
default:
/* currently we don't use interrogate data */
break;
}
} else if (irb->esw.esw0.erw.cons) {
sense = irb->ecw;
}
return sense;
}
EXPORT_SYMBOL_GPL(dasd_get_sense);
void dasd_generic_shutdown(struct ccw_device *cdev)
{
struct dasd_device *device;
device = dasd_device_from_cdev(cdev);
if (IS_ERR(device))
return;
if (device->block)
dasd_schedule_block_bh(device->block);
dasd_schedule_device_bh(device);
wait_event(shutdown_waitq, _wait_for_empty_queues(device));
}
EXPORT_SYMBOL_GPL(dasd_generic_shutdown);
static int __init dasd_init(void)
{
int rc;
init_waitqueue_head(&dasd_init_waitq);
init_waitqueue_head(&dasd_flush_wq);
init_waitqueue_head(&generic_waitq);
init_waitqueue_head(&shutdown_waitq);
/* register 'common' DASD debug area, used for all DBF_XXX calls */
dasd_debug_area = debug_register("dasd", 1, 1, 8 * sizeof(long));
if (dasd_debug_area == NULL) {
rc = -ENOMEM;
goto failed;
}
debug_register_view(dasd_debug_area, &debug_sprintf_view);
debug_set_level(dasd_debug_area, DBF_WARNING);
DBF_EVENT(DBF_EMERG, "%s", "debug area created");
dasd_diag_discipline_pointer = NULL;
dasd_statistics_createroot();
rc = dasd_devmap_init();
if (rc)
goto failed;
rc = dasd_gendisk_init();
if (rc)
goto failed;
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)
goto failed;
#endif
return 0;
failed:
pr_info("The DASD device driver could not be initialized\n");
dasd_exit();
return rc;
}
module_init(dasd_init);
module_exit(dasd_exit);
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