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authorYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 12:17:53 -0700
committerYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 15:44:42 -0700
commit9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (patch)
tree1c9cafbcd35f783a87880a10f85d1a060db1a563 /kernel/drivers/s390/block/dasd.c
parent98260f3884f4a202f9ca5eabed40b1354c489b29 (diff)
Add the rt linux 4.1.3-rt3 as base
Import the rt linux 4.1.3-rt3 as OPNFV kvm base. It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and the base is: commit 0917f823c59692d751951bf5ea699a2d1e2f26a2 Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Date: Sat Jul 25 12:13:34 2015 +0200 Prepare v4.1.3-rt3 Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> We lose all the git history this way and it's not good. We should apply another opnfv project repo in future. Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423 Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>
Diffstat (limited to 'kernel/drivers/s390/block/dasd.c')
-rw-r--r--kernel/drivers/s390/block/dasd.c3879
1 files changed, 3879 insertions, 0 deletions
diff --git a/kernel/drivers/s390/block/dasd.c b/kernel/drivers/s390/block/dasd.c
new file mode 100644
index 000000000..57fd66357
--- /dev/null
+++ b/kernel/drivers/s390/block/dasd.c
@@ -0,0 +1,3879 @@
+/*
+ * 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
+
+/*
+ * 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 void dasd_flush_request_queue(struct dasd_block *);
+static int dasd_flush_block_queue(struct dasd_block *);
+static void dasd_device_tasklet(struct dasd_device *);
+static void dasd_block_tasklet(struct dasd_block *);
+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 dasd_return_cqr_cb(struct dasd_ccw_req *, void *);
+static void dasd_device_timeout(unsigned long);
+static void dasd_block_timeout(unsigned long);
+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 *);
+
+/*
+ * 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,
+ (void (*)(unsigned long)) dasd_device_tasklet,
+ (unsigned long) device);
+ INIT_LIST_HEAD(&device->ccw_queue);
+ init_timer(&device->timer);
+ device->timer.function = dasd_device_timeout;
+ device->timer.data = (unsigned long) device;
+ INIT_WORK(&device->kick_work, do_kick_device);
+ INIT_WORK(&device->restore_device, do_restore_device);
+ INIT_WORK(&device->reload_device, do_reload_device);
+ 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);
+
+ spin_lock_init(&block->request_queue_lock);
+ atomic_set(&block->tasklet_scheduled, 0);
+ tasklet_init(&block->tasklet,
+ (void (*)(unsigned long)) dasd_block_tasklet,
+ (unsigned long) block);
+ INIT_LIST_HEAD(&block->ccw_queue);
+ spin_lock_init(&block->queue_lock);
+ init_timer(&block->timer);
+ block->timer.function = dasd_block_timeout;
+ block->timer.data = (unsigned long) block;
+ 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);
+ /* 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;
+ 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);
+
+ /* 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);
+ 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;
+
+ 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;
+ 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_flush_request_queue(block);
+ 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));
+ getnstimeofday(&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)
+{
+ long strtime, irqtime, endtime, tottime; /* in microseconds */
+ long tottimeps, sectors;
+ struct dasd_device *device;
+ int sectors_ind, tottime_ind, tottimeps_ind, strtime_ind;
+ int irqtime_ind, irqtimeps_ind, endtime_ind;
+
+ 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) {
+ 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)
+ 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)
+ 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));
+ getnstimeofday(&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;
+ }
+ getnstimeofday(&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 %ld.%09ld\n",
+ 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_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 */
+
+/*
+ * Allocate memory for a channel program with 'cplength' channel
+ * command words and 'datasize' additional space. There are two
+ * variantes: 1) dasd_kmalloc_request uses kmalloc to get the needed
+ * memory and 2) dasd_smalloc_request uses the static ccw memory
+ * that gets allocated for each device.
+ */
+struct dasd_ccw_req *dasd_kmalloc_request(int magic, int cplength,
+ int datasize,
+ struct dasd_device *device)
+{
+ struct dasd_ccw_req *cqr;
+
+ /* Sanity checks */
+ BUG_ON(datasize > PAGE_SIZE ||
+ (cplength*sizeof(struct ccw1)) > PAGE_SIZE);
+
+ cqr = kzalloc(sizeof(struct dasd_ccw_req), GFP_ATOMIC);
+ if (cqr == NULL)
+ return ERR_PTR(-ENOMEM);
+ cqr->cpaddr = NULL;
+ if (cplength > 0) {
+ cqr->cpaddr = kcalloc(cplength, sizeof(struct ccw1),
+ GFP_ATOMIC | GFP_DMA);
+ if (cqr->cpaddr == NULL) {
+ kfree(cqr);
+ return ERR_PTR(-ENOMEM);
+ }
+ }
+ cqr->data = NULL;
+ if (datasize > 0) {
+ cqr->data = kzalloc(datasize, GFP_ATOMIC | GFP_DMA);
+ if (cqr->data == NULL) {
+ kfree(cqr->cpaddr);
+ kfree(cqr);
+ return ERR_PTR(-ENOMEM);
+ }
+ }
+ cqr->magic = magic;
+ set_bit(DASD_CQR_FLAGS_USE_ERP, &cqr->flags);
+ dasd_get_device(device);
+ return cqr;
+}
+EXPORT_SYMBOL(dasd_kmalloc_request);
+
+struct dasd_ccw_req *dasd_smalloc_request(int magic, int cplength,
+ int datasize,
+ struct dasd_device *device)
+{
+ unsigned long flags;
+ struct dasd_ccw_req *cqr;
+ char *data;
+ int size;
+
+ size = (sizeof(struct dasd_ccw_req) + 7L) & -8L;
+ if (cplength > 0)
+ size += cplength * sizeof(struct ccw1);
+ if (datasize > 0)
+ size += datasize;
+ spin_lock_irqsave(&device->mem_lock, flags);
+ cqr = (struct dasd_ccw_req *)
+ dasd_alloc_chunk(&device->ccw_chunks, size);
+ spin_unlock_irqrestore(&device->mem_lock, flags);
+ if (cqr == NULL)
+ return ERR_PTR(-ENOMEM);
+ memset(cqr, 0, sizeof(struct dasd_ccw_req));
+ data = (char *) cqr + ((sizeof(struct dasd_ccw_req) + 7L) & -8L);
+ cqr->cpaddr = NULL;
+ if (cplength > 0) {
+ cqr->cpaddr = (struct ccw1 *) data;
+ data += cplength*sizeof(struct ccw1);
+ memset(cqr->cpaddr, 0, cplength*sizeof(struct ccw1));
+ }
+ cqr->data = NULL;
+ 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);
+
+/*
+ * Free memory of a channel program. This function needs to free all the
+ * idal lists that might have been created by dasd_set_cda and the
+ * struct dasd_ccw_req itself.
+ */
+void dasd_kfree_request(struct dasd_ccw_req *cqr, struct dasd_device *device)
+{
+ struct ccw1 *ccw;
+
+ /* Clear any idals used for the request. */
+ ccw = cqr->cpaddr;
+ do {
+ clear_normalized_cda(ccw);
+ } while (ccw++->flags & (CCW_FLAG_CC | CCW_FLAG_DC));
+ kfree(cqr->cpaddr);
+ kfree(cqr->data);
+ kfree(cqr);
+ dasd_put_device(device);
+}
+EXPORT_SYMBOL(dasd_kfree_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);
+ 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 -EIO:
+ DBF_DEV_EVENT(DBF_ERR, device, "%s",
+ "I/O error, 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;
+ case -EBUSY:
+ DBF_DEV_EVENT(DBF_ERR, device, "%s",
+ "device busy, retry later");
+ 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 &= device->path_data.opm;
+ if (!cqr->lpm)
+ cqr->lpm = device->path_data.opm;
+ }
+ 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 -ETIMEDOUT:
+ DBF_DEV_EVENT(DBF_WARNING, device, "%s",
+ "start_IO: request timeout, 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 != device->path_data.opm) {
+ cqr->lpm = device->path_data.opm;
+ 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);
+ device->path_data.opm = 0;
+ device->path_data.ppm = 0;
+ device->path_data.npm = 0;
+ device->path_data.tbvpm =
+ 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(unsigned long ptr)
+{
+ unsigned long flags;
+ struct dasd_device *device;
+
+ device = (struct dasd_device *) ptr;
+ 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);
+}
+EXPORT_SYMBOL_GPL(dasd_generic_handle_state_change);
+
+/*
+ * 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 long now;
+ int expires;
+
+ if (IS_ERR(irb)) {
+ switch (PTR_ERR(irb)) {
+ case -EIO:
+ 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();
+ cqr = (struct dasd_ccw_req *) intparm;
+ /* 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;
+ }
+ 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);
+ 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 */
+ /*
+ * 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 == device->path_data.opm)
+ 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 = device->path_data.opm;
+ 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);
+ }
+}
+
+/*
+ * 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;
+ void (*callback)(struct dasd_ccw_req *, void *data);
+ void *callback_data;
+ char errorstring[ERRORLENGTH];
+
+ 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;
+ callback = cqr->callback;
+ callback_data = cqr->callback_data;
+ if (block)
+ spin_lock_bh(&block->queue_lock);
+ 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 != NULL)
+ (callback)(cqr, callback_data);
+ if (block)
+ 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);
+ }
+ }
+}
+
+/*
+ * 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;
+ /* when device is stopped, return request to previous layer
+ * exception: only the disconnect or unresumed bits are set and the
+ * cqr is a path verification request
+ */
+ if (device->stopped &&
+ !(!(device->stopped & ~(DASD_STOPPED_DC_WAIT | DASD_UNRESUMED_PM))
+ && test_bit(DASD_CQR_VERIFY_PATH, &cqr->flags))) {
+ 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 (device->path_data.tbvpm) {
+ if (device->stopped & ~(DASD_STOPPED_DC_WAIT |
+ DASD_UNRESUMED_PM))
+ return;
+ rc = device->discipline->verify_path(
+ device, device->path_data.tbvpm);
+ if (rc)
+ dasd_device_set_timer(device, 50);
+ else
+ device->path_data.tbvpm = 0;
+ }
+};
+
+/*
+ * 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(struct dasd_device *device)
+{
+ 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 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;
+ 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) {
+ /*
+ * 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.
+ */
+int dasd_cancel_req(struct dasd_ccw_req *cqr)
+{
+ struct dasd_device *device = cqr->startdev;
+ unsigned long flags;
+ int rc;
+
+ rc = 0;
+ spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags);
+ switch (cqr->status) {
+ case DASD_CQR_QUEUED:
+ /* request was not started - just set to cleared */
+ cqr->status = DASD_CQR_CLEARED;
+ if (cqr->callback_data == DASD_SLEEPON_START_TAG)
+ cqr->callback_data = DASD_SLEEPON_END_TAG;
+ 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;
+ }
+ spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
+ dasd_schedule_device_bh(device);
+ return rc;
+}
+EXPORT_SYMBOL(dasd_cancel_req);
+
+/*
+ * 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(unsigned long ptr)
+{
+ unsigned long flags;
+ struct dasd_block *block;
+
+ block = (struct dasd_block *) ptr;
+ 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);
+}
+
+/*
+ * 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);
+}
+
+/*
+ * Fetch requests from the block device queue.
+ */
+static void __dasd_process_request_queue(struct dasd_block *block)
+{
+ struct request_queue *queue;
+ struct request *req;
+ struct dasd_ccw_req *cqr;
+ struct dasd_device *basedev;
+ unsigned long flags;
+ queue = block->request_queue;
+ basedev = block->base;
+ /* No queue ? Then there is nothing to do. */
+ if (queue == NULL)
+ return;
+
+ /*
+ * We requeue request from the block device queue to the ccw
+ * queue only in two states. In state DASD_STATE_READY the
+ * partition detection is done and we need to requeue requests
+ * for that. State DASD_STATE_ONLINE is normal block device
+ * operation.
+ */
+ if (basedev->state < DASD_STATE_READY) {
+ while ((req = blk_fetch_request(block->request_queue)))
+ __blk_end_request_all(req, -EIO);
+ return;
+ }
+
+ /* if device ist stopped do not fetch new requests */
+ if (basedev->stopped)
+ return;
+
+ /* Now we try to fetch requests from the request queue */
+ while ((req = blk_peek_request(queue))) {
+ if (basedev->features & DASD_FEATURE_READONLY &&
+ rq_data_dir(req) == WRITE) {
+ DBF_DEV_EVENT(DBF_ERR, basedev,
+ "Rejecting write request %p",
+ req);
+ blk_start_request(req);
+ __blk_end_request_all(req, -EIO);
+ continue;
+ }
+ 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);
+ blk_start_request(req);
+ __blk_end_request_all(req, -ETIMEDOUT);
+ continue;
+ }
+ cqr = basedev->discipline->build_cp(basedev, block, req);
+ if (IS_ERR(cqr)) {
+ if (PTR_ERR(cqr) == -EBUSY)
+ break; /* normal end condition */
+ if (PTR_ERR(cqr) == -ENOMEM)
+ break; /* terminate request queue loop */
+ if (PTR_ERR(cqr) == -EAGAIN) {
+ /*
+ * The current request cannot be build right
+ * now, we have to try later. If this request
+ * is the head-of-queue we stop the device
+ * for 1/2 second.
+ */
+ if (!list_empty(&block->ccw_queue))
+ break;
+ spin_lock_irqsave(
+ get_ccwdev_lock(basedev->cdev), flags);
+ dasd_device_set_stop_bits(basedev,
+ DASD_STOPPED_PENDING);
+ spin_unlock_irqrestore(
+ get_ccwdev_lock(basedev->cdev), flags);
+ dasd_block_set_timer(block, HZ/2);
+ break;
+ }
+ DBF_DEV_EVENT(DBF_ERR, basedev,
+ "CCW creation failed (rc=%ld) "
+ "on request %p",
+ PTR_ERR(cqr), req);
+ blk_start_request(req);
+ __blk_end_request_all(req, -EIO);
+ continue;
+ }
+ /*
+ * Note: callback is set to dasd_return_cqr_cb in
+ * __dasd_block_start_head to cover erp requests as well
+ */
+ cqr->callback_data = (void *) req;
+ cqr->status = DASD_CQR_FILLED;
+ req->completion_data = cqr;
+ blk_start_request(req);
+ list_add_tail(&cqr->blocklist, &block->ccw_queue);
+ INIT_LIST_HEAD(&cqr->devlist);
+ dasd_profile_start(block, cqr, req);
+ }
+}
+
+static void __dasd_cleanup_cqr(struct dasd_ccw_req *cqr)
+{
+ struct request *req;
+ int status;
+ int error = 0;
+
+ 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 = status;
+ else if (status == 0) {
+ if (cqr->intrc == -EPERM)
+ error = -EBADE;
+ else if (cqr->intrc == -ENOLINK ||
+ cqr->intrc == -ETIMEDOUT)
+ error = cqr->intrc;
+ else
+ error = -EIO;
+ }
+ __blk_end_request_all(req, error);
+}
+
+/*
+ * 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(struct dasd_block *block)
+{
+ struct list_head final_queue;
+ struct list_head *l, *n;
+ struct dasd_ccw_req *cqr;
+
+ atomic_set(&block->tasklet_scheduled, 0);
+ INIT_LIST_HEAD(&final_queue);
+ spin_lock(&block->queue_lock);
+ /* Finish off requests on ccw queue */
+ __dasd_process_block_ccw_queue(block, &final_queue);
+ spin_unlock(&block->queue_lock);
+ /* Now call the callback function of requests with final status */
+ spin_lock_irq(&block->request_queue_lock);
+ list_for_each_safe(l, n, &final_queue) {
+ cqr = list_entry(l, struct dasd_ccw_req, blocklist);
+ list_del_init(&cqr->blocklist);
+ __dasd_cleanup_cqr(cqr);
+ }
+ spin_lock(&block->queue_lock);
+ /* Get new request from the block device request queue */
+ __dasd_process_request_queue(block);
+ /* Now check if the head of the ccw queue needs to be started. */
+ __dasd_block_start_head(block);
+ spin_unlock(&block->queue_lock);
+ spin_unlock_irq(&block->request_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;
+ unsigned long flags;
+
+ if (!block)
+ return -EINVAL;
+ spin_lock_irqsave(&block->queue_lock, flags);
+ req = (struct request *) cqr->callback_data;
+ blk_requeue_request(block->request_queue, req);
+ spin_unlock_irqrestore(&block->queue_lock, flags);
+
+ 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;
+
+ 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_irq(&block->request_queue_lock);
+ cqr->endclk = get_tod_clock();
+ list_del_init(&cqr->blocklist);
+ __dasd_cleanup_cqr(cqr);
+ spin_unlock_irq(&block->request_queue_lock);
+ }
+ 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 void do_dasd_request(struct request_queue *queue)
+{
+ struct dasd_block *block;
+
+ block = queue->queuedata;
+ spin_lock(&block->queue_lock);
+ /* Get new request from the block device request queue */
+ __dasd_process_request_queue(block);
+ /* Now check if the head of the ccw queue needs to be started. */
+ __dasd_block_start_head(block);
+ spin_unlock(&block->queue_lock);
+}
+
+/*
+ * Block timeout callback, called from the block layer
+ *
+ * request_queue lock is held on entry.
+ *
+ * Return values:
+ * BLK_EH_RESET_TIMER if the request should be left running
+ * BLK_EH_NOT_HANDLED if the request is handled or terminated
+ * by the driver.
+ */
+enum blk_eh_timer_return dasd_times_out(struct request *req)
+{
+ struct dasd_ccw_req *cqr = req->completion_data;
+ struct dasd_block *block = req->q->queuedata;
+ struct dasd_device *device;
+ int rc = 0;
+
+ if (!cqr)
+ return BLK_EH_NOT_HANDLED;
+
+ device = cqr->startdev ? cqr->startdev : block->base;
+ if (!device->blk_timeout)
+ 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) {
+ spin_unlock(get_ccwdev_lock(device->cdev));
+ rc = dasd_cancel_req(cqr);
+ } else if (cqr->status == DASD_CQR_FILLED ||
+ cqr->status == DASD_CQR_NEED_ERP) {
+ cqr->status = DASD_CQR_TERMINATED;
+ spin_unlock(get_ccwdev_lock(device->cdev));
+ } 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) {
+ spin_unlock(get_ccwdev_lock(device->cdev));
+ rc = dasd_cancel_req(searchcqr);
+ spin_lock(get_ccwdev_lock(device->cdev));
+ } 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);
+
+ return rc ? BLK_EH_RESET_TIMER : BLK_EH_NOT_HANDLED;
+}
+
+/*
+ * Allocate and initialize request queue and default I/O scheduler.
+ */
+static int dasd_alloc_queue(struct dasd_block *block)
+{
+ block->request_queue = blk_init_queue(do_dasd_request,
+ &block->request_queue_lock);
+ if (block->request_queue == NULL)
+ return -ENOMEM;
+
+ block->request_queue->queuedata = block;
+
+ return 0;
+}
+
+/*
+ * Allocate and initialize request queue.
+ */
+static void dasd_setup_queue(struct dasd_block *block)
+{
+ 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_logical_block_size(block->request_queue,
+ block->bp_block);
+ blk_queue_max_hw_sectors(block->request_queue, max);
+ blk_queue_max_segments(block->request_queue, -1L);
+ /* with page sized segments we can translate each segement into
+ * one idaw/tidaw
+ */
+ blk_queue_max_segment_size(block->request_queue, PAGE_SIZE);
+ blk_queue_segment_boundary(block->request_queue, PAGE_SIZE - 1);
+}
+
+/*
+ * Deactivate and free request queue.
+ */
+static void dasd_free_queue(struct dasd_block *block)
+{
+ if (block->request_queue) {
+ blk_cleanup_queue(block->request_queue);
+ block->request_queue = NULL;
+ }
+}
+
+/*
+ * Flush request on the request queue.
+ */
+static void dasd_flush_request_queue(struct dasd_block *block)
+{
+ struct request *req;
+
+ if (!block->request_queue)
+ return;
+
+ spin_lock_irq(&block->request_queue_lock);
+ while ((req = blk_fetch_request(block->request_queue)))
+ __blk_end_request_all(req, -EIO);
+ spin_unlock_irq(&block->request_queue_lock);
+}
+
+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);
+
+/*
+ * 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) {
+ 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;
+
+ rc = 0;
+ device = dasd_device_from_cdev(cdev);
+ if (IS_ERR(device))
+ 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));
+ clear_bit(DASD_FLAG_OFFLINE, &device->flags);
+ dasd_put_device(device);
+ return -EBUSY;
+ }
+ }
+
+ if (test_bit(DASD_FLAG_SAFE_OFFLINE_RUNNING, &device->flags)) {
+ /*
+ * safe offline already running
+ * could only be called by normal offline so safe_offline flag
+ * needs to be removed to run normal offline and kill all I/O
+ */
+ if (test_and_set_bit(DASD_FLAG_OFFLINE, &device->flags)) {
+ /* Already doing normal offline processing */
+ dasd_put_device(device);
+ return -EBUSY;
+ } else
+ clear_bit(DASD_FLAG_SAFE_OFFLINE, &device->flags);
+
+ } else
+ if (test_bit(DASD_FLAG_OFFLINE, &device->flags)) {
+ /* Already doing offline processing */
+ dasd_put_device(device);
+ return -EBUSY;
+ }
+
+ /*
+ * if safe_offline 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)) {
+ /*
+ * 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
+ */
+ /* sync blockdev and partitions */
+ rc = fsync_bdev(device->block->bdev);
+ if (rc != 0)
+ goto interrupted;
+
+ /* schedule device tasklet and wait for completion */
+ dasd_schedule_device_bh(device);
+ rc = wait_event_interruptible(shutdown_waitq,
+ _wait_for_empty_queues(device));
+ if (rc != 0)
+ goto interrupted;
+ }
+
+ set_bit(DASD_FLAG_OFFLINE, &device->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 */
+ clear_bit(DASD_FLAG_SAFE_OFFLINE, &device->flags);
+ clear_bit(DASD_FLAG_SAFE_OFFLINE_RUNNING, &device->flags);
+ clear_bit(DASD_FLAG_OFFLINE, &device->flags);
+ dasd_put_device(device);
+ 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->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:
+ device->path_data.opm = 0;
+ device->path_data.ppm = 0;
+ device->path_data.npm = 0;
+ ret = dasd_generic_last_path_gone(device);
+ break;
+ case CIO_OPER:
+ ret = 1;
+ if (device->path_data.opm)
+ 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)
+{
+ int chp;
+ __u8 oldopm, eventlpm;
+ struct dasd_device *device;
+
+ device = dasd_device_from_cdev_locked(cdev);
+ if (IS_ERR(device))
+ return;
+ for (chp = 0; chp < 8; chp++) {
+ eventlpm = 0x80 >> chp;
+ if (path_event[chp] & PE_PATH_GONE) {
+ oldopm = device->path_data.opm;
+ device->path_data.opm &= ~eventlpm;
+ device->path_data.ppm &= ~eventlpm;
+ device->path_data.npm &= ~eventlpm;
+ if (oldopm && !device->path_data.opm) {
+ 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);
+ }
+ }
+ if (path_event[chp] & PE_PATH_AVAILABLE) {
+ device->path_data.opm &= ~eventlpm;
+ device->path_data.ppm &= ~eventlpm;
+ device->path_data.npm &= ~eventlpm;
+ device->path_data.tbvpm |= eventlpm;
+ dasd_schedule_device_bh(device);
+ }
+ if (path_event[chp] & PE_PATHGROUP_ESTABLISHED) {
+ if (!(device->path_data.opm & eventlpm) &&
+ !(device->path_data.tbvpm & eventlpm)) {
+ /*
+ * we can not establish a pathgroup on an
+ * unavailable path, so trigger a path
+ * verification first
+ */
+ device->path_data.tbvpm |= eventlpm;
+ 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);
+ }
+ }
+ dasd_put_device(device);
+}
+EXPORT_SYMBOL_GPL(dasd_generic_path_event);
+
+int dasd_generic_verify_path(struct dasd_device *device, __u8 lpm)
+{
+ if (!device->path_data.opm && lpm) {
+ device->path_data.opm = lpm;
+ dasd_generic_path_operational(device);
+ } else
+ device->path_data.opm |= lpm;
+ return 0;
+}
+EXPORT_SYMBOL_GPL(dasd_generic_verify_path);
+
+
+int dasd_generic_pm_freeze(struct ccw_device *cdev)
+{
+ struct dasd_device *device = dasd_device_from_cdev(cdev);
+ struct list_head freeze_queue;
+ struct dasd_ccw_req *cqr, *n;
+ struct dasd_ccw_req *refers;
+ int rc;
+
+ if (IS_ERR(device))
+ return PTR_ERR(device);
+
+ /* mark device as suspended */
+ set_bit(DASD_FLAG_SUSPENDED, &device->flags);
+
+ if (device->discipline->freeze)
+ rc = device->discipline->freeze(device);
+
+ /* disallow new I/O */
+ dasd_device_set_stop_bits(device, DASD_STOPPED_PM);
+
+ /* clear active requests and requeue them to block layer if possible */
+ INIT_LIST_HEAD(&freeze_queue);
+ spin_lock_irq(get_ccwdev_lock(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(cdev));
+ dasd_put_device(device);
+ return rc;
+ }
+ }
+ list_move_tail(&cqr->devlist, &freeze_queue);
+ }
+ spin_unlock_irq(get_ccwdev_lock(cdev));
+
+ list_for_each_entry_safe(cqr, n, &freeze_queue, devlist) {
+ wait_event(dasd_flush_wq,
+ (cqr->status != DASD_CQR_CLEAR_PENDING));
+ if (cqr->status == DASD_CQR_CLEARED)
+ cqr->status = DASD_CQR_QUEUED;
+
+ /* 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;
+ }
+ if (cqr->block)
+ 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(&freeze_queue)) {
+ /* move freeze_queue to start of the ccw_queue */
+ spin_lock_irq(get_ccwdev_lock(cdev));
+ list_splice_tail(&freeze_queue, &device->ccw_queue);
+ spin_unlock_irq(get_ccwdev_lock(cdev));
+ }
+ dasd_put_device(device);
+ return rc;
+}
+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);
+
+ 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);
+
+ 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);