/* * File...........: linux/drivers/s390/block/dasd.c * Author(s)......: Holger Smolinski * Horst Hummel * Carsten Otte * Martin Schwidefsky * Bugreports.to..: * Copyright IBM Corp. 1999, 2009 */ #define KMSG_COMPONENT "dasd" #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include /* This is ugly... */ #define PRINTK_HEADER "dasd:" #include "dasd_int.h" /* * SECTION: Constant definitions to be used within this file */ #define DASD_CHANQ_MAX_SIZE 4 #define DASD_SLEEPON_START_TAG (void *) 1 #define DASD_SLEEPON_END_TAG (void *) 2 /* * SECTION: exported variables of dasd.c */ debug_info_t *dasd_debug_area; static struct dentry *dasd_debugfs_root_entry; struct dasd_discipline *dasd_diag_discipline_pointer; void dasd_int_handler(struct ccw_device *, unsigned long, struct irb *); MODULE_AUTHOR("Holger Smolinski "); MODULE_DESCRIPTION("Linux on S/390 DASD device driver," " Copyright 2000 IBM Corporation"); 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; /* * 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; } /* * Free memory of a device structure. */ void dasd_free_block(struct dasd_block *block) { kfree(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; /* 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 0; } /* * 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->block) { dasd_profile_exit(&device->block->profile); if (device->block->debugfs_dentry) 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); if (device->debugfs_dentry) 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; 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; } else { device->state = DASD_STATE_READY; } return rc; } /* * 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) { int rc; struct gendisk *disk; struct disk_part_iter piter; struct hd_struct *part; if (device->discipline->ready_to_online) { rc = device->discipline->ready_to_online(device); if (rc) return rc; } 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; if (device->state == device->target) wake_up(&dasd_init_waitq); /* let user-space know that the device status changed */ kobject_uevent(&device->cdev->dev.kobj, KOBJ_CHANGE); } /* * 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. */ schedule_work(&device->kick_work); } /* * 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. */ schedule_work(&device->reload_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. */ schedule_work(&device->restore_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); } /* * 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); } /* * 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_info dasd_global_profile_data; static struct dentry *dasd_global_profile_dentry; 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; if (dasd_global_profile_level) { 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_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); if (dasd_global_profile_level) { 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_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); } void dasd_global_profile_reset(void) { memset(&dasd_global_profile_data, 0, sizeof(dasd_global_profile_data)); getnstimeofday(&dasd_global_profile_data.starttod); } 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) rc = user_len; } else if (strncmp(str, "off", 3) == 0) { dasd_profile_off(prof); } else rc = -EINVAL; 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_printf(m, "histogram_sectors "); dasd_stats_array(m, data->dasd_io_secs); seq_printf(m, "histogram_io_times "); dasd_stats_array(m, data->dasd_io_times); seq_printf(m, "histogram_io_times_weighted "); dasd_stats_array(m, data->dasd_io_timps); seq_printf(m, "histogram_time_build_to_ssch "); dasd_stats_array(m, data->dasd_io_time1); seq_printf(m, "histogram_time_ssch_to_irq "); dasd_stats_array(m, data->dasd_io_time2); seq_printf(m, "histogram_time_ssch_to_irq_weighted "); dasd_stats_array(m, data->dasd_io_time2ps); seq_printf(m, "histogram_time_irq_to_end "); dasd_stats_array(m, data->dasd_io_time3); seq_printf(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_printf(m, "histogram_read_sectors "); dasd_stats_array(m, data->dasd_read_secs); seq_printf(m, "histogram_read_times "); dasd_stats_array(m, data->dasd_read_times); seq_printf(m, "histogram_read_time_build_to_ssch "); dasd_stats_array(m, data->dasd_read_time1); seq_printf(m, "histogram_read_time_ssch_to_irq "); dasd_stats_array(m, data->dasd_read_time2); seq_printf(m, "histogram_read_time_irq_to_end "); dasd_stats_array(m, data->dasd_read_time3); seq_printf(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_printf(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 ssize_t dasd_stats_global_write(struct file *file, const char __user *user_buf, size_t user_len, loff_t *pos) { char *buffer, *str; ssize_t rc; 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_global_profile_reset(); } else if (strncmp(str, "on", 2) == 0) { dasd_global_profile_reset(); dasd_global_profile_level = DASD_PROFILE_GLOBAL_ONLY; } else if (strncmp(str, "off", 3) == 0) { dasd_global_profile_level = DASD_PROFILE_OFF; } else rc = -EINVAL; vfree(buffer); return rc; } static int dasd_stats_global_show(struct seq_file *m, void *v) { if (!dasd_global_profile_level) { seq_printf(m, "disabled\n"); return 0; } dasd_stats_seq_print(m, &dasd_global_profile_data); return 0; } static int dasd_stats_global_open(struct inode *inode, struct file *file) { return single_open(file, dasd_stats_global_show, NULL); } static const struct file_operations dasd_stats_global_fops = { .owner = THIS_MODULE, .open = dasd_stats_global_open, .read = seq_read, .llseek = seq_lseek, .release = single_release, .write = dasd_stats_global_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); if (profile->dentry) { debugfs_remove(profile->dentry); profile->dentry = NULL; } } static void dasd_statistics_removeroot(void) { dasd_global_profile_level = DASD_PROFILE_OFF; if (dasd_global_profile_dentry) { debugfs_remove(dasd_global_profile_dentry); dasd_global_profile_dentry = NULL; } if (dasd_debugfs_global_entry) debugfs_remove(dasd_debugfs_global_entry); if (dasd_debugfs_root_entry) debugfs_remove(dasd_debugfs_root_entry); } static void dasd_statistics_createroot(void) { umode_t mode; struct dentry *pde; dasd_debugfs_root_entry = NULL; dasd_debugfs_global_entry = NULL; dasd_global_profile_dentry = 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; mode = (S_IRUSR | S_IWUSR | S_IFREG); pde = debugfs_create_file("statistics", mode, dasd_debugfs_global_entry, NULL, &dasd_stats_global_fops); if (!pde || IS_ERR(pde)) goto error; dasd_global_profile_dentry = pde; 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_printf(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; } 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; } /* * 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) { #ifdef CONFIG_64BIT 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)); #endif kfree(cqr->cpaddr); kfree(cqr->data); kfree(cqr); dasd_put_device(device); } 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); } /* * 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_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: 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; } /* * 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_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; } /* * 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); } /* * Clear timeout for a device. */ void dasd_device_clear_timer(struct dasd_device *device) { del_timer(&device->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); } /* * 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_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); } 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); } 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); /* Stop list processing at the first non-final request. */ if (cqr->status == DASD_CQR_QUEUED || cqr->status == DASD_CQR_IN_IO || cqr->status == DASD_CQR_CLEAR_PENDING) break; 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 (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_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; } /* * 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)); 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); } 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); } /* * 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); } /* * 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; 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; 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_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; } /* * 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); } /* * 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); } /* * 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; return rc; } /* * 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 1 if the request has been terminated. * 0 if there was no need to terminate the request (not started yet) * 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; 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_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; } /* * 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); } /* * Clear timeout for a dasd_block. */ void dasd_block_clear_timer(struct dasd_block *block) { del_timer(&block->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 fai