diff options
Diffstat (limited to 'kernel/drivers/s390/block/dasd.c')
| -rw-r--r-- | kernel/drivers/s390/block/dasd.c | 3879 |
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); |