/* * File...........: linux/drivers/s390/block/dasd.c * Author(s)......: Holger Smolinski * Horst Hummel * Carsten Otte * Martin Schwidefsky * Bugreports.to..: * (C) IBM Corporation, IBM Deutschland Entwicklung GmbH, 1999-2001 * */ #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 /* * SECTION: exported variables of dasd.c */ debug_info_t *dasd_debug_area; 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 dasd_return_cqr_cb(struct dasd_ccw_req *, void *); /* * SECTION: Operations on the device structure. */ static wait_queue_head_t dasd_init_waitq; static wait_queue_head_t dasd_flush_wq; /* * 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); INIT_WORK(&device->kick_work, do_kick_device); device->state = DASD_STATE_NEW; device->target = DASD_STATE_NEW; 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); 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; } /* * Request the irq line for the device. */ static int dasd_state_known_to_basic(struct dasd_device *device) { int rc; /* Allocate and register gendisk structure. */ if (device->block) { rc = dasd_gendisk_alloc(device->block); if (rc) return rc; } /* register 'device' debug area, used for all DBF_DEV_XXX calls */ device->debug_area = debug_register(device->cdev->dev.bus_id, 1, 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_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); 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_destroy_partitions(block); dasd_flush_request_queue(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; 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); return 0; } /* * Stop the requeueing of requests again. */ static int dasd_state_online_to_ready(struct dasd_device *device) { int rc; if (device->discipline->online_to_ready) { rc = device->discipline->online_to_ready(device); if (rc) return rc; } device->state = DASD_STATE_READY; 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 && rc != -EAGAIN) 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); dasd_change_state(device); 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); } /* * Set the target state for a device and starts the state change. */ void dasd_set_target_state(struct dasd_device *device, int target) { /* 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); } /* * 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)); } /* * SECTION: device operation (interrupt handler, start i/o, term i/o ...) */ #ifdef CONFIG_DASD_PROFILE struct dasd_profile_info_t dasd_global_profile; unsigned int dasd_profile_level = DASD_PROFILE_OFF; /* * Increments counter in global and local profiling structures. */ #define dasd_profile_counter(value, counter, block) \ { \ int index; \ for (index = 0; index < 31 && value >> (2+index); index++); \ dasd_global_profile.counter[index]++; \ block->profile.counter[index]++; \ } /* * 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; if (dasd_profile_level != DASD_PROFILE_ON) return; /* count the length of the chanq for statistics */ counter = 0; list_for_each(l, &block->ccw_queue) if (++counter >= 31) break; dasd_global_profile.dasd_io_nr_req[counter]++; block->profile.dasd_io_nr_req[counter]++; } /* * Add profiling information for cqr after execution. */ 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; if (dasd_profile_level != DASD_PROFILE_ON) return; sectors = req->nr_sectors; 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; if (!dasd_global_profile.dasd_io_reqs) memset(&dasd_global_profile, 0, sizeof(struct dasd_profile_info_t)); dasd_global_profile.dasd_io_reqs++; dasd_global_profile.dasd_io_sects += sectors; if (!block->profile.dasd_io_reqs) memset(&block->profile, 0, sizeof(struct dasd_profile_info_t)); block->profile.dasd_io_reqs++; block->profile.dasd_io_sects += sectors; dasd_profile_counter(sectors, dasd_io_secs, block); dasd_profile_counter(tottime, dasd_io_times, block); dasd_profile_counter(tottimeps, dasd_io_timps, block); dasd_profile_counter(strtime, dasd_io_time1, block); dasd_profile_counter(irqtime, dasd_io_time2, block); dasd_profile_counter(irqtime / sectors, dasd_io_time2ps, block); dasd_profile_counter(endtime, dasd_io_time3, block); } #else #define dasd_profile_start(block, cqr, req) do {} while (0) #define dasd_profile_end(block, cqr, req) do {} while (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(char *magic, int cplength, int datasize, struct dasd_device *device) { struct dasd_ccw_req *cqr; /* Sanity checks */ BUG_ON( magic == NULL || 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); } } strncpy((char *) &cqr->magic, magic, 4); ASCEBC((char *) &cqr->magic, 4); set_bit(DASD_CQR_FLAGS_USE_ERP, &cqr->flags); dasd_get_device(device); return cqr; } struct dasd_ccw_req *dasd_smalloc_request(char *magic, int cplength, int datasize, struct dasd_device *device) { unsigned long flags; struct dasd_ccw_req *cqr; char *data; int size; /* Sanity checks */ BUG_ON( magic == NULL || datasize > PAGE_SIZE || (cplength*sizeof(struct ccw1)) > PAGE_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); } strncpy((char *) &cqr->magic, magic, 4); ASCEBC((char *) &cqr->magic, 4); 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)) { DEV_MESSAGE(KERN_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; /* 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->retries--; 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: DEV_MESSAGE(KERN_ERR, device, "line %d unknown RC=%d, please " "report to linux390@de.ibm.com", __LINE__, rc); 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; /* Check the cqr */ rc = dasd_check_cqr(cqr); if (rc) return rc; device = (struct dasd_device *) cqr->startdev; if (cqr->retries < 0) { DEV_MESSAGE(KERN_DEBUG, device, "start_IO: request %p (%02x/%i) - no retry left.", cqr, cqr->status, cqr->retries); cqr->status = DASD_CQR_ERROR; return -EIO; } cqr->startclk = get_clock(); cqr->starttime = jiffies; cqr->retries--; rc = ccw_device_start(device->cdev, cqr->cpaddr, (long) cqr, cqr->lpm, 0); switch (rc) { case 0: cqr->status = DASD_CQR_IN_IO; DBF_DEV_EVENT(DBF_DEBUG, device, "start_IO: request %p started successful", cqr); break; case -EBUSY: DBF_DEV_EVENT(DBF_ERR, device, "%s", "start_IO: device busy, retry later"); break; case -ETIMEDOUT: DBF_DEV_EVENT(DBF_ERR, device, "%s", "start_IO: request timeout, retry later"); break; case -EACCES: /* -EACCES indicates that the request used only a * subset of the available pathes and all these * pathes are gone. * Do a retry with all available pathes. */ cqr->lpm = LPM_ANYPATH; DBF_DEV_EVENT(DBF_ERR, device, "%s", "start_IO: selected pathes gone," " retry on all pathes"); break; case -ENODEV: case -EIO: DBF_DEV_EVENT(DBF_ERR, device, "%s", "start_IO: device gone, retry"); break; default: DEV_MESSAGE(KERN_ERR, device, "line %d unknown RC=%d, please report" " to linux390@de.ibm.com", __LINE__, rc); BUG(); break; } 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 */ device->stopped &= ~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) { if (timer_pending(&device->timer)) del_timer(&device->timer); return; } if (timer_pending(&device->timer)) { if (mod_timer(&device->timer, jiffies + expires)) return; } device->timer.function = dasd_device_timeout; device->timer.data = (unsigned long) device; device->timer.expires = jiffies + expires; add_timer(&device->timer); } /* * Clear timeout for a device. */ void dasd_device_clear_timer(struct dasd_device *device) { if (timer_pending(&device->timer)) 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; cqr = (struct dasd_ccw_req *) intparm; if (cqr->status != DASD_CQR_IN_IO) { MESSAGE(KERN_DEBUG, "invalid status in handle_killed_request: " "bus_id %s, status %02x", cdev->dev.bus_id, cqr->status); return; } device = (struct dasd_device *) cqr->startdev; if (device == NULL || device != dasd_device_from_cdev_locked(cdev) || strncmp(device->discipline->ebcname, (char *) &cqr->magic, 4)) { MESSAGE(KERN_DEBUG, "invalid device in request: bus_id %s", cdev->dev.bus_id); 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); device->stopped &= ~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: dasd_handle_killed_request(cdev, intparm); break; case -ETIMEDOUT: printk(KERN_WARNING"%s(%s): request timed out\n", __FUNCTION__, cdev->dev.bus_id); //FIXME - dasd uses own timeout interface... break; default: printk(KERN_WARNING"%s(%s): unknown error %ld\n", __FUNCTION__, cdev->dev.bus_id, PTR_ERR(irb)); } return; } now = get_clock(); DBF_EVENT(DBF_ERR, "Interrupt: bus_id %s CS/DS %04x ip %08x", cdev->dev.bus_id, ((irb->scsw.cstat<<8)|irb->scsw.dstat), (unsigned int) intparm); /* check for unsolicited interrupts */ cqr = (struct dasd_ccw_req *) intparm; if (!cqr || ((irb->scsw.cc == 1) && (irb->scsw.fctl & SCSW_FCTL_START_FUNC) && (irb->scsw.stctl & SCSW_STCTL_STATUS_PEND)) ) { if (cqr && cqr->status == DASD_CQR_IN_IO) cqr->status = DASD_CQR_QUEUED; device = dasd_device_from_cdev_locked(cdev); if (!IS_ERR(device)) { dasd_device_clear_timer(device); device->discipline->handle_unsolicited_interrupt(device, irb); dasd_put_device(device); } return; } device = (struct dasd_device *) cqr->startdev; if (!device || strncmp(device->discipline->ebcname, (char *) &cqr->magic, 4)) { MESSAGE(KERN_DEBUG, "invalid device in request: bus_id %s", cdev->dev.bus_id); return; } /* Check for clear pending */ if (cqr->status == DASD_CQR_CLEAR_PENDING && irb->scsw.fctl & 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) { MESSAGE(KERN_DEBUG, "invalid status: bus_id %s, status %02x", cdev->dev.bus_id, cqr->status); return; } DBF_DEV_EVENT(DBF_DEBUG, device, "Int: CS/DS 0x%04x for cqr %p", ((irb->scsw.cstat << 8) | irb->scsw.dstat), cqr); next = NULL; expires = 0; if (irb->scsw.dstat == (DEV_STAT_CHN_END | DEV_STAT_DEV_END) && irb->scsw.cstat == 0 && !irb->esw.esw0.erw.cons) { /* 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 */ memcpy(&cqr->irb, irb, sizeof(struct irb)); if (device->features & DASD_FEATURE_ERPLOG) { dasd_log_sense(cqr, irb); } /* If we have no sense data, or we just don't want complex ERP * for this request, but if we have retries left, then just * reset this request and retry it in the fastpath */ if (!(cqr->irb.esw.esw0.erw.cons && test_bit(DASD_CQR_FLAGS_USE_ERP, &cqr->flags)) && cqr->retries > 0) { DEV_MESSAGE(KERN_DEBUG, device, "default ERP in fastpath (%i retries left)", cqr->retries); cqr->lpm = LPM_ANYPATH; 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; else DEV_MESSAGE(KERN_DEBUG, device, "%s", "Interrupt fastpath " "failed!"); } if (expires != 0) dasd_device_set_timer(device, expires); else dasd_device_clear_timer(device); dasd_schedule_device_bh(device); } /* * 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; list_for_each_safe(l, n, final_queue) { cqr = list_entry(l, struct dasd_ccw_req, devlist); list_del_init(&cqr->devlist); if (cqr->block) spin_lock_bh(&cqr->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: DEV_MESSAGE(KERN_ERR, device, "wrong cqr status in __dasd_process_final_queue " "for cqr %p, status %x", cqr, cqr->status); BUG(); } if (cqr->block) spin_unlock_bh(&cqr->block->queue_lock); if (cqr->callback != NULL) (cqr->callback)(cqr, cqr->callback_data); } } /* * 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_MESSAGE(KERN_ERR, device, "internal error - timeout (%is) expired " "for cqr %p, termination failed, " "retrying in 5s", (cqr->expires/HZ), cqr); cqr->expires += 5*HZ; dasd_device_set_timer(device, 5*HZ); } else { DEV_MESSAGE(KERN_ERR, device, "internal error - timeout (%is) expired " "for cqr %p (%i retries left)", (cqr->expires/HZ), cqr, 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 */ if (device->stopped) { 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); } /* * 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_MESSAGE(KERN_ERR, device, "dasd flush ccw_queue is unable " " to terminate request %p", 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); 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); } /* * 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. */ static void dasd_wakeup_cb(struct dasd_ccw_req *cqr, void *data) { wake_up((wait_queue_head_t *) data); } 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->status == DASD_CQR_DONE || cqr->status == DASD_CQR_NEED_ERP || cqr->status == DASD_CQR_TERMINATED) && list_empty(&cqr->devlist)); spin_unlock_irq(get_ccwdev_lock(device->cdev)); 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) { wait_queue_head_t wait_q; struct dasd_device *device; int rc; device = cqr->startdev; init_waitqueue_head (&wait_q); cqr->callback = dasd_wakeup_cb; cqr->callback_data = (void *) &wait_q; dasd_add_request_tail(cqr); wait_event(wait_q, _wait_for_wakeup(cqr)); /* Request status is either done or failed. */ rc = (cqr->status == DASD_CQR_DONE) ? 0 : -EIO; return rc; } /* * 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) { wait_queue_head_t wait_q; struct dasd_device *device; int rc; device = cqr->startdev; init_waitqueue_head (&wait_q); cqr->callback = dasd_wakeup_cb; cqr->callback_data = (void *) &wait_q; dasd_add_request_tail(cqr); rc = wait_event_interruptible(wait_q, _wait_for_wakeup(cqr)); if (rc == -ERESTARTSYS) { dasd_cancel_req(cqr); /* wait (non-interruptible) for final status */ wait_event(wait_q, _wait_for_wakeup(cqr)); } rc = (cqr->status == DASD_CQR_DONE) ? 0 : -EIO; return rc; } /* * 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; if (list_empty(&device->ccw_queue)) return 0; cqr = list_entry(device->ccw_queue.next, struct dasd_ccw_req, devlist); return device->discipline->term_IO(cqr); } int dasd_sleep_on_immediatly(struct dasd_ccw_req *cqr) { wait_queue_head_t wait_q; struct dasd_device *device; int rc; device = cqr->startdev; 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; } init_waitqueue_head (&wait_q); cqr->callback = dasd_wakeup_cb; cqr->callback_data = (void *) &wait_q; 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_irq(get_ccwdev_lock(device->cdev)); wait_event(wait_q, _wait_for_wakeup(cqr)); /* Request status is either done or failed. */ rc = (cqr->status == DASD_CQR_DONE) ? 0 : -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_MESSAGE(KERN_ERR, device, "dasd_cancel_req is unable " " to terminate request %p, rc = %d", cqr, rc); } else { cqr->stopclk = get_clock(); rc = 1; } 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 */ block->base->stopped &= ~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) { if (timer_pending(&block->timer)) del_timer(&block->timer); return; } if (timer_pending(&block->timer)) { if (mod_timer(&block->timer, jiffies + expires)) return; } block->timer.function = dasd_block_timeout; block->timer.data = (unsigned long) block; block->timer.expires = jiffies + expires; add_timer(&block->timer); } /* * Clear timeout for a dasd_block. */ void dasd_block_clear_timer(struct dasd_block *block) { if (timer_pending(&block->timer)) del_timer(&block->timer); } /* * posts the buffer_cache about a finalized request */ static inline void dasd_end_request(struct request *req, int uptodate) { if (end_that_request_first(req, uptodate, req->hard_nr_sectors)) BUG(); add_disk_randomness(req->rq_disk); end_that_request_last(req, uptodate); } /* * Process finished error recovery ccw. */ static inline void __dasd_block_process_erp(struct dasd_block *block, struct dasd_ccw_req *cqr) { dasd_erp_fn_t erp_fn; struct dasd_device *device = block->base; if (cqr->status == DASD_CQR_DONE) DBF_DEV_EVENT(DBF_NOTICE, device, "%s", "ERP successful"); else DEV_MESSAGE(KERN_ERR, device, "%s", "ERP unsuccessful"); 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) return; /* Now we try to fetch requests from the request queue */ while (!blk_queue_plugged(queue) && elv_next_request(queue)) { req = elv_next_request(queue); if (basedev->features & DASD_FEATURE_READONLY && rq_data_dir(req) == WRITE) { DBF_DEV_EVENT(DBF_ERR, basedev, "Rejecting write request %p", req); blkdev_dequeue_request(req); dasd_end_request(req, 0); 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); basedev->stopped |= 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); blkdev_dequeue_request(req); dasd_end_request(req, 0); 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; blkdev_dequeue_request(req); list_add_tail(&cqr->blocklist, &block->ccw_queue); dasd_profile_start(block, cqr, req); } } static void __dasd_cleanup_cqr(struct dasd_ccw_req *cqr) { struct request *req; int status; req = (struct request *) cqr->callback_data; dasd_profile_end(cqr->block, cqr, req); status = cqr->memdev->discipline->free_cp(cqr, req); dasd_end_request(req, status); } /* * 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) { if (cqr->irb.esw.esw0.erw.cons && test_bit(DASD_CQR_FLAGS_USE_ERP, &cqr->flags)) { erp_fn = base->discipline->erp_action(cqr); erp_fn(cqr); } goto restart; } /* 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); base->stopped |= DASD_STOPPED_QUIESCE; spin_unlock_irqrestore(get_ccwdev_lock(base->cdev), flags); goto restart; } /* Process finished ERP request. */ if (cqr->refers) { __dasd_block_process_erp(block, cqr); goto restart; } /* Rechain finished requests to final queue */ cqr->endclk = get_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; /* 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; 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); dasd_put_device(block->base); } static void _dasd_wake_block_flush_cb(struct dasd_ccw_req *cqr, void *data) { wake_up(&dasd_flush_wq); } /* * 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) { __dasd_block_process_erp(block, cqr); /* restart list_for_xx loop since dasd_process_erp * might remove multiple elements */ goto restart_cb; } /* call the callback function */ cqr->endclk = get_clock(); list_del_init(&cqr->blocklist); __dasd_cleanup_cqr(cqr); } 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); } /* * 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); } /* * Allocate and initialize request queue and default I/O scheduler. */ static int dasd_alloc_queue(struct dasd_block *block) { int rc; 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; elevator_exit(block->request_queue->elevator); rc = elevator_init(block->request_queue, "deadline"); if (rc) { blk_cleanup_queue(block->request_queue); return rc; } return 0; } /* * Allocate and initialize request queue. */ static void dasd_setup_queue(struct dasd_block *block) { int max; blk_queue_hardsect_size(block->request_queue, block->bp_block); max = block->base->discipline->max_blocks << block->s2b_shift; blk_queue_max_sectors(block->request_queue, max); blk_queue_max_phys_segments(block->request_queue, -1L); blk_queue_max_hw_segments(block->request_queue, -1L); blk_queue_max_segment_size(block->request_queue, -1L); blk_queue_segment_boundary(block->request_queue, -1L); blk_queue_ordered(block->request_queue, QUEUE_ORDERED_DRAIN, NULL); } /* * 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 = elv_next_request(block->request_queue))) { blkdev_dequeue_request(req); dasd_end_request(req, 0); } spin_unlock_irq(&block->request_queue_lock); } static int dasd_open(struct inode *inp, struct file *filp) { struct gendisk *disk = inp->i_bdev->bd_disk; struct dasd_block *block = disk->private_data; struct dasd_device *base = block->base; int rc; atomic_inc(&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_MESSAGE(KERN_INFO, base, "%s", "No access to device due to probeonly mode"); 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; } return 0; out: module_put(base->discipline->owner); unlock: atomic_dec(&block->open_count); return rc; } static int dasd_release(struct inode *inp, struct file *filp) { struct gendisk *disk = inp->i_bdev->bd_disk; struct dasd_block *block = disk->private_data; atomic_dec(&block->open_count); module_put(block->base->discipline->owner); return 0; } /* * Return disk geometry. */ static int dasd_getgeo(struct block_device *bdev, struct hd_geometry *geo) { struct dasd_block *block; struct dasd_device *base; block = bdev->bd_disk->private_data; base = block->base; if (!block) return -ENODEV; if (!base->discipline || !base->discipline->fill_geometry) return -EINVAL; base->discipline->fill_geometry(block, geo); geo->start = get_start_sect(bdev) >> block->s2b_shift; return 0; } struct block_device_operations dasd_device_operations = { .owner = THIS_MODULE, .open = dasd_open, .release = dasd_release, .ioctl = dasd_ioctl, .compat_ioctl = dasd_compat_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; } } /* * SECTION: common functions for ccw_driver use */ /* * 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 = ccw_device_set_options(cdev, CCWDEV_DO_PATHGROUP); if (ret) { printk(KERN_WARNING "dasd_generic_probe: could not set ccw-device options " "for %s\n", cdev->dev.bus_id); return ret; } ret = dasd_add_sysfs_files(cdev); if (ret) { printk(KERN_WARNING "dasd_generic_probe: could not add sysfs entries " "for %s\n", cdev->dev.bus_id); 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(cdev->dev.bus_id) != 0)) ret = ccw_device_set_online(cdev); if (ret) printk(KERN_WARNING "dasd_generic_probe: could not initially " "online ccw-device %s; return code: %d\n", cdev->dev.bus_id, ret); return 0; } /* * 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; dasd_remove_sysfs_files(cdev); device = dasd_device_from_cdev(cdev); if (IS_ERR(device)) return; if (test_and_set_bit(DASD_FLAG_OFFLINE, &device->flags)) { /* Already doing offline processing */ dasd_put_device(device); 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; device->block = NULL; 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); } /* * 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) { printk (KERN_WARNING "dasd_generic couldn't online device %s " "- discipline DIAG not available\n", cdev->dev.bus_id); 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) { printk (KERN_WARNING "dasd_generic couldn't online device %s " "with discipline %s rc=%i\n", cdev->dev.bus_id, 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) { printk (KERN_WARNING "dasd_generic discipline not found for %s\n", cdev->dev.bus_id); 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", cdev->dev.bus_id); /* FIXME: we have to wait for the root device but we don't want * to wait for each single device but for all at once. */ wait_event(dasd_init_waitq, _wait_for_device(device)); dasd_put_device(device); return rc; } int dasd_generic_set_offline(struct ccw_device *cdev) { struct dasd_device *device; struct dasd_block *block; int max_count, open_count; device = dasd_device_from_cdev(cdev); if (IS_ERR(device)) return PTR_ERR(device); if (test_and_set_bit(DASD_FLAG_OFFLINE, &device->flags)) { /* Already doing offline processing */ dasd_put_device(device); return 0; } /* * 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) { struct dasd_block *block = device->block; max_count = block->bdev ? 0 : -1; open_count = (int) atomic_read(&block->open_count); if (open_count > max_count) { if (open_count > 0) printk(KERN_WARNING "Can't offline dasd " "device with open count = %i.\n", open_count); else printk(KERN_WARNING "%s", "Can't offline dasd device due " "to internal use\n"); clear_bit(DASD_FLAG_OFFLINE, &device->flags); dasd_put_device(device); return -EBUSY; } } dasd_set_target_state(device, DASD_STATE_NEW); /* dasd_delete_device destroys the device reference. */ block = device->block; device->block = NULL; 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; } int dasd_generic_notify(struct ccw_device *cdev, int event) { struct dasd_device *device; struct dasd_ccw_req *cqr; unsigned long flags; int ret; device = dasd_device_from_cdev(cdev); if (IS_ERR(device)) return 0; spin_lock_irqsave(get_ccwdev_lock(cdev), flags); ret = 0; switch (event) { case CIO_GONE: case CIO_NO_PATH: /* First of all call extended error reporting. */ dasd_eer_write(device, NULL, DASD_EER_NOPATH); if (device->state < DASD_STATE_BASIC) break; /* 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_QUEUED; cqr->retries++; } device->stopped |= DASD_STOPPED_DC_WAIT; dasd_device_clear_timer(device); dasd_schedule_device_bh(device); ret = 1; break; case CIO_OPER: /* FIXME: add a sanity check. */ device->stopped &= ~DASD_STOPPED_DC_WAIT; dasd_schedule_device_bh(device); if (device->block) dasd_schedule_block_bh(device->block); ret = 1; break; } spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags); dasd_put_device(device); return ret; } static struct dasd_ccw_req *dasd_generic_build_rdc(struct dasd_device *device, void *rdc_buffer, int rdc_buffer_size, char *magic) { struct dasd_ccw_req *cqr; struct ccw1 *ccw; cqr = dasd_smalloc_request(magic, 1 /* RDC */, rdc_buffer_size, device); if (IS_ERR(cqr)) { DEV_MESSAGE(KERN_WARNING, device, "%s", "Could not allocate RDC request"); return cqr; } ccw = cqr->cpaddr; ccw->cmd_code = CCW_CMD_RDC; ccw->cda = (__u32)(addr_t)rdc_buffer; ccw->count = rdc_buffer_size; cqr->startdev = device; cqr->memdev = device; cqr->expires = 10*HZ; clear_bit(DASD_CQR_FLAGS_USE_ERP, &cqr->flags); cqr->retries = 2; cqr->buildclk = get_clock(); cqr->status = DASD_CQR_FILLED; return cqr; } int dasd_generic_read_dev_chars(struct dasd_device *device, char *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); static int __init dasd_init(void) { int rc; init_waitqueue_head(&dasd_init_waitq); init_waitqueue_head(&dasd_flush_wq); /* 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; 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: MESSAGE(KERN_INFO, "%s", "initialization not performed due to errors"); dasd_exit(); return rc; } module_init(dasd_init); module_exit(dasd_exit); EXPORT_SYMBOL(dasd_debug_area); EXPORT_SYMBOL(dasd_diag_discipline_pointer); EXPORT_SYMBOL(dasd_add_request_head); EXPORT_SYMBOL(dasd_add_request_tail); EXPORT_SYMBOL(dasd_cancel_req); EXPORT_SYMBOL(dasd_device_clear_timer); EXPORT_SYMBOL(dasd_block_clear_timer); EXPORT_SYMBOL(dasd_enable_device); EXPORT_SYMBOL(dasd_int_handler); EXPORT_SYMBOL(dasd_kfree_request); EXPORT_SYMBOL(dasd_kick_device); EXPORT_SYMBOL(dasd_kmalloc_request); EXPORT_SYMBOL(dasd_schedule_device_bh); EXPORT_SYMBOL(dasd_schedule_block_bh); EXPORT_SYMBOL(dasd_set_target_state); EXPORT_SYMBOL(dasd_device_set_timer); EXPORT_SYMBOL(dasd_block_set_timer); EXPORT_SYMBOL(dasd_sfree_request); EXPORT_SYMBOL(dasd_sleep_on); EXPORT_SYMBOL(dasd_sleep_on_immediatly); EXPORT_SYMBOL(dasd_sleep_on_interruptible); EXPORT_SYMBOL(dasd_smalloc_request); EXPORT_SYMBOL(dasd_start_IO); EXPORT_SYMBOL(dasd_term_IO); EXPORT_SYMBOL_GPL(dasd_generic_probe); EXPORT_SYMBOL_GPL(dasd_generic_remove); EXPORT_SYMBOL_GPL(dasd_generic_notify); EXPORT_SYMBOL_GPL(dasd_generic_set_online); EXPORT_SYMBOL_GPL(dasd_generic_set_offline); EXPORT_SYMBOL_GPL(dasd_generic_handle_state_change); EXPORT_SYMBOL_GPL(dasd_flush_device_queue); EXPORT_SYMBOL_GPL(dasd_alloc_block); EXPORT_SYMBOL_GPL(dasd_free_block);