| /* |
| * drivers/s390/char/tape_core.c |
| * basic function of the tape device driver |
| * |
| * S390 and zSeries version |
| * Copyright (C) 2001,2005 IBM Deutschland Entwicklung GmbH, IBM Corporation |
| * Author(s): Carsten Otte <cotte@de.ibm.com> |
| * Michael Holzheu <holzheu@de.ibm.com> |
| * Tuan Ngo-Anh <ngoanh@de.ibm.com> |
| * Martin Schwidefsky <schwidefsky@de.ibm.com> |
| * Stefan Bader <shbader@de.ibm.com> |
| */ |
| |
| #include <linux/module.h> |
| #include <linux/init.h> // for kernel parameters |
| #include <linux/kmod.h> // for requesting modules |
| #include <linux/spinlock.h> // for locks |
| #include <linux/vmalloc.h> |
| #include <linux/list.h> |
| |
| #include <asm/types.h> // for variable types |
| |
| #define TAPE_DBF_AREA tape_core_dbf |
| |
| #include "tape.h" |
| #include "tape_std.h" |
| |
| #define PRINTK_HEADER "TAPE_CORE: " |
| |
| static void __tape_do_irq (struct ccw_device *, unsigned long, struct irb *); |
| static void tape_delayed_next_request(struct work_struct *); |
| |
| /* |
| * One list to contain all tape devices of all disciplines, so |
| * we can assign the devices to minor numbers of the same major |
| * The list is protected by the rwlock |
| */ |
| static struct list_head tape_device_list = LIST_HEAD_INIT(tape_device_list); |
| static DEFINE_RWLOCK(tape_device_lock); |
| |
| /* |
| * Pointer to debug area. |
| */ |
| debug_info_t *TAPE_DBF_AREA = NULL; |
| EXPORT_SYMBOL(TAPE_DBF_AREA); |
| |
| /* |
| * Printable strings for tape enumerations. |
| */ |
| const char *tape_state_verbose[TS_SIZE] = |
| { |
| [TS_UNUSED] = "UNUSED", |
| [TS_IN_USE] = "IN_USE", |
| [TS_BLKUSE] = "BLKUSE", |
| [TS_INIT] = "INIT ", |
| [TS_NOT_OPER] = "NOT_OP" |
| }; |
| |
| const char *tape_op_verbose[TO_SIZE] = |
| { |
| [TO_BLOCK] = "BLK", [TO_BSB] = "BSB", |
| [TO_BSF] = "BSF", [TO_DSE] = "DSE", |
| [TO_FSB] = "FSB", [TO_FSF] = "FSF", |
| [TO_LBL] = "LBL", [TO_NOP] = "NOP", |
| [TO_RBA] = "RBA", [TO_RBI] = "RBI", |
| [TO_RFO] = "RFO", [TO_REW] = "REW", |
| [TO_RUN] = "RUN", [TO_WRI] = "WRI", |
| [TO_WTM] = "WTM", [TO_MSEN] = "MSN", |
| [TO_LOAD] = "LOA", [TO_READ_CONFIG] = "RCF", |
| [TO_READ_ATTMSG] = "RAT", |
| [TO_DIS] = "DIS", [TO_ASSIGN] = "ASS", |
| [TO_UNASSIGN] = "UAS" |
| }; |
| |
| static inline int |
| busid_to_int(char *bus_id) |
| { |
| int dec; |
| int d; |
| char * s; |
| |
| for(s = bus_id, d = 0; *s != '\0' && *s != '.'; s++) |
| d = (d * 10) + (*s - '0'); |
| dec = d; |
| for(s++, d = 0; *s != '\0' && *s != '.'; s++) |
| d = (d * 10) + (*s - '0'); |
| dec = (dec << 8) + d; |
| |
| for(s++; *s != '\0'; s++) { |
| if (*s >= '0' && *s <= '9') { |
| d = *s - '0'; |
| } else if (*s >= 'a' && *s <= 'f') { |
| d = *s - 'a' + 10; |
| } else { |
| d = *s - 'A' + 10; |
| } |
| dec = (dec << 4) + d; |
| } |
| |
| return dec; |
| } |
| |
| /* |
| * Some channel attached tape specific attributes. |
| * |
| * FIXME: In the future the first_minor and blocksize attribute should be |
| * replaced by a link to the cdev tree. |
| */ |
| static ssize_t |
| tape_medium_state_show(struct device *dev, struct device_attribute *attr, char *buf) |
| { |
| struct tape_device *tdev; |
| |
| tdev = (struct tape_device *) dev->driver_data; |
| return scnprintf(buf, PAGE_SIZE, "%i\n", tdev->medium_state); |
| } |
| |
| static |
| DEVICE_ATTR(medium_state, 0444, tape_medium_state_show, NULL); |
| |
| static ssize_t |
| tape_first_minor_show(struct device *dev, struct device_attribute *attr, char *buf) |
| { |
| struct tape_device *tdev; |
| |
| tdev = (struct tape_device *) dev->driver_data; |
| return scnprintf(buf, PAGE_SIZE, "%i\n", tdev->first_minor); |
| } |
| |
| static |
| DEVICE_ATTR(first_minor, 0444, tape_first_minor_show, NULL); |
| |
| static ssize_t |
| tape_state_show(struct device *dev, struct device_attribute *attr, char *buf) |
| { |
| struct tape_device *tdev; |
| |
| tdev = (struct tape_device *) dev->driver_data; |
| return scnprintf(buf, PAGE_SIZE, "%s\n", (tdev->first_minor < 0) ? |
| "OFFLINE" : tape_state_verbose[tdev->tape_state]); |
| } |
| |
| static |
| DEVICE_ATTR(state, 0444, tape_state_show, NULL); |
| |
| static ssize_t |
| tape_operation_show(struct device *dev, struct device_attribute *attr, char *buf) |
| { |
| struct tape_device *tdev; |
| ssize_t rc; |
| |
| tdev = (struct tape_device *) dev->driver_data; |
| if (tdev->first_minor < 0) |
| return scnprintf(buf, PAGE_SIZE, "N/A\n"); |
| |
| spin_lock_irq(get_ccwdev_lock(tdev->cdev)); |
| if (list_empty(&tdev->req_queue)) |
| rc = scnprintf(buf, PAGE_SIZE, "---\n"); |
| else { |
| struct tape_request *req; |
| |
| req = list_entry(tdev->req_queue.next, struct tape_request, |
| list); |
| rc = scnprintf(buf,PAGE_SIZE, "%s\n", tape_op_verbose[req->op]); |
| } |
| spin_unlock_irq(get_ccwdev_lock(tdev->cdev)); |
| return rc; |
| } |
| |
| static |
| DEVICE_ATTR(operation, 0444, tape_operation_show, NULL); |
| |
| static ssize_t |
| tape_blocksize_show(struct device *dev, struct device_attribute *attr, char *buf) |
| { |
| struct tape_device *tdev; |
| |
| tdev = (struct tape_device *) dev->driver_data; |
| |
| return scnprintf(buf, PAGE_SIZE, "%i\n", tdev->char_data.block_size); |
| } |
| |
| static |
| DEVICE_ATTR(blocksize, 0444, tape_blocksize_show, NULL); |
| |
| static struct attribute *tape_attrs[] = { |
| &dev_attr_medium_state.attr, |
| &dev_attr_first_minor.attr, |
| &dev_attr_state.attr, |
| &dev_attr_operation.attr, |
| &dev_attr_blocksize.attr, |
| NULL |
| }; |
| |
| static struct attribute_group tape_attr_group = { |
| .attrs = tape_attrs, |
| }; |
| |
| /* |
| * Tape state functions |
| */ |
| void |
| tape_state_set(struct tape_device *device, enum tape_state newstate) |
| { |
| const char *str; |
| |
| if (device->tape_state == TS_NOT_OPER) { |
| DBF_EVENT(3, "ts_set err: not oper\n"); |
| return; |
| } |
| DBF_EVENT(4, "ts. dev: %x\n", device->first_minor); |
| DBF_EVENT(4, "old ts:\t\n"); |
| if (device->tape_state < TS_SIZE && device->tape_state >=0 ) |
| str = tape_state_verbose[device->tape_state]; |
| else |
| str = "UNKNOWN TS"; |
| DBF_EVENT(4, "%s\n", str); |
| DBF_EVENT(4, "new ts:\t\n"); |
| if (newstate < TS_SIZE && newstate >= 0) |
| str = tape_state_verbose[newstate]; |
| else |
| str = "UNKNOWN TS"; |
| DBF_EVENT(4, "%s\n", str); |
| device->tape_state = newstate; |
| wake_up(&device->state_change_wq); |
| } |
| |
| void |
| tape_med_state_set(struct tape_device *device, enum tape_medium_state newstate) |
| { |
| if (device->medium_state == newstate) |
| return; |
| switch(newstate){ |
| case MS_UNLOADED: |
| device->tape_generic_status |= GMT_DR_OPEN(~0); |
| PRINT_INFO("(%s): Tape is unloaded\n", |
| device->cdev->dev.bus_id); |
| break; |
| case MS_LOADED: |
| device->tape_generic_status &= ~GMT_DR_OPEN(~0); |
| PRINT_INFO("(%s): Tape has been mounted\n", |
| device->cdev->dev.bus_id); |
| break; |
| default: |
| // print nothing |
| break; |
| } |
| device->medium_state = newstate; |
| wake_up(&device->state_change_wq); |
| } |
| |
| /* |
| * Stop running ccw. Has to be called with the device lock held. |
| */ |
| static inline int |
| __tape_cancel_io(struct tape_device *device, struct tape_request *request) |
| { |
| int retries; |
| int rc; |
| |
| /* Check if interrupt has already been processed */ |
| if (request->callback == NULL) |
| return 0; |
| |
| rc = 0; |
| for (retries = 0; retries < 5; retries++) { |
| rc = ccw_device_clear(device->cdev, (long) request); |
| |
| switch (rc) { |
| case 0: |
| request->status = TAPE_REQUEST_DONE; |
| return 0; |
| case -EBUSY: |
| request->status = TAPE_REQUEST_CANCEL; |
| schedule_delayed_work(&device->tape_dnr, 0); |
| return 0; |
| case -ENODEV: |
| DBF_EXCEPTION(2, "device gone, retry\n"); |
| break; |
| case -EIO: |
| DBF_EXCEPTION(2, "I/O error, retry\n"); |
| break; |
| default: |
| BUG(); |
| } |
| } |
| |
| return rc; |
| } |
| |
| /* |
| * Add device into the sorted list, giving it the first |
| * available minor number. |
| */ |
| static int |
| tape_assign_minor(struct tape_device *device) |
| { |
| struct tape_device *tmp; |
| int minor; |
| |
| minor = 0; |
| write_lock(&tape_device_lock); |
| list_for_each_entry(tmp, &tape_device_list, node) { |
| if (minor < tmp->first_minor) |
| break; |
| minor += TAPE_MINORS_PER_DEV; |
| } |
| if (minor >= 256) { |
| write_unlock(&tape_device_lock); |
| return -ENODEV; |
| } |
| device->first_minor = minor; |
| list_add_tail(&device->node, &tmp->node); |
| write_unlock(&tape_device_lock); |
| return 0; |
| } |
| |
| /* remove device from the list */ |
| static void |
| tape_remove_minor(struct tape_device *device) |
| { |
| write_lock(&tape_device_lock); |
| list_del_init(&device->node); |
| device->first_minor = -1; |
| write_unlock(&tape_device_lock); |
| } |
| |
| /* |
| * Set a device online. |
| * |
| * This function is called by the common I/O layer to move a device from the |
| * detected but offline into the online state. |
| * If we return an error (RC < 0) the device remains in the offline state. This |
| * can happen if the device is assigned somewhere else, for example. |
| */ |
| int |
| tape_generic_online(struct tape_device *device, |
| struct tape_discipline *discipline) |
| { |
| int rc; |
| |
| DBF_LH(6, "tape_enable_device(%p, %p)\n", device, discipline); |
| |
| if (device->tape_state != TS_INIT) { |
| DBF_LH(3, "Tapestate not INIT (%d)\n", device->tape_state); |
| return -EINVAL; |
| } |
| |
| /* Let the discipline have a go at the device. */ |
| device->discipline = discipline; |
| if (!try_module_get(discipline->owner)) { |
| PRINT_ERR("Cannot get module. Module gone.\n"); |
| return -EINVAL; |
| } |
| |
| rc = discipline->setup_device(device); |
| if (rc) |
| goto out; |
| rc = tape_assign_minor(device); |
| if (rc) |
| goto out_discipline; |
| |
| rc = tapechar_setup_device(device); |
| if (rc) |
| goto out_minor; |
| rc = tapeblock_setup_device(device); |
| if (rc) |
| goto out_char; |
| |
| tape_state_set(device, TS_UNUSED); |
| |
| DBF_LH(3, "(%08x): Drive set online\n", device->cdev_id); |
| |
| return 0; |
| |
| out_char: |
| tapechar_cleanup_device(device); |
| out_discipline: |
| device->discipline->cleanup_device(device); |
| device->discipline = NULL; |
| out_minor: |
| tape_remove_minor(device); |
| out: |
| module_put(discipline->owner); |
| return rc; |
| } |
| |
| static inline void |
| tape_cleanup_device(struct tape_device *device) |
| { |
| tapeblock_cleanup_device(device); |
| tapechar_cleanup_device(device); |
| device->discipline->cleanup_device(device); |
| module_put(device->discipline->owner); |
| tape_remove_minor(device); |
| tape_med_state_set(device, MS_UNKNOWN); |
| } |
| |
| /* |
| * Set device offline. |
| * |
| * Called by the common I/O layer if the drive should set offline on user |
| * request. We may prevent this by returning an error. |
| * Manual offline is only allowed while the drive is not in use. |
| */ |
| int |
| tape_generic_offline(struct tape_device *device) |
| { |
| if (!device) { |
| PRINT_ERR("tape_generic_offline: no such device\n"); |
| return -ENODEV; |
| } |
| |
| DBF_LH(3, "(%08x): tape_generic_offline(%p)\n", |
| device->cdev_id, device); |
| |
| spin_lock_irq(get_ccwdev_lock(device->cdev)); |
| switch (device->tape_state) { |
| case TS_INIT: |
| case TS_NOT_OPER: |
| spin_unlock_irq(get_ccwdev_lock(device->cdev)); |
| break; |
| case TS_UNUSED: |
| tape_state_set(device, TS_INIT); |
| spin_unlock_irq(get_ccwdev_lock(device->cdev)); |
| tape_cleanup_device(device); |
| break; |
| default: |
| DBF_EVENT(3, "(%08x): Set offline failed " |
| "- drive in use.\n", |
| device->cdev_id); |
| PRINT_WARN("(%s): Set offline failed " |
| "- drive in use.\n", |
| device->cdev->dev.bus_id); |
| spin_unlock_irq(get_ccwdev_lock(device->cdev)); |
| return -EBUSY; |
| } |
| |
| DBF_LH(3, "(%08x): Drive set offline.\n", device->cdev_id); |
| return 0; |
| } |
| |
| /* |
| * Allocate memory for a new device structure. |
| */ |
| static struct tape_device * |
| tape_alloc_device(void) |
| { |
| struct tape_device *device; |
| |
| device = kzalloc(sizeof(struct tape_device), GFP_KERNEL); |
| if (device == NULL) { |
| DBF_EXCEPTION(2, "ti:no mem\n"); |
| PRINT_INFO ("can't allocate memory for " |
| "tape info structure\n"); |
| return ERR_PTR(-ENOMEM); |
| } |
| device->modeset_byte = kmalloc(1, GFP_KERNEL | GFP_DMA); |
| if (device->modeset_byte == NULL) { |
| DBF_EXCEPTION(2, "ti:no mem\n"); |
| PRINT_INFO("can't allocate memory for modeset byte\n"); |
| kfree(device); |
| return ERR_PTR(-ENOMEM); |
| } |
| INIT_LIST_HEAD(&device->req_queue); |
| INIT_LIST_HEAD(&device->node); |
| init_waitqueue_head(&device->state_change_wq); |
| device->tape_state = TS_INIT; |
| device->medium_state = MS_UNKNOWN; |
| *device->modeset_byte = 0; |
| device->first_minor = -1; |
| atomic_set(&device->ref_count, 1); |
| INIT_DELAYED_WORK(&device->tape_dnr, tape_delayed_next_request); |
| |
| return device; |
| } |
| |
| /* |
| * Get a reference to an existing device structure. This will automatically |
| * increment the reference count. |
| */ |
| struct tape_device * |
| tape_get_device_reference(struct tape_device *device) |
| { |
| DBF_EVENT(4, "tape_get_device_reference(%p) = %i\n", device, |
| atomic_inc_return(&device->ref_count)); |
| |
| return device; |
| } |
| |
| /* |
| * Decrease the reference counter of a devices structure. If the |
| * reference counter reaches zero free the device structure. |
| * The function returns a NULL pointer to be used by the caller |
| * for clearing reference pointers. |
| */ |
| struct tape_device * |
| tape_put_device(struct tape_device *device) |
| { |
| int remain; |
| |
| remain = atomic_dec_return(&device->ref_count); |
| if (remain > 0) { |
| DBF_EVENT(4, "tape_put_device(%p) -> %i\n", device, remain); |
| } else { |
| if (remain < 0) { |
| DBF_EVENT(4, "put device without reference\n"); |
| PRINT_ERR("put device without reference\n"); |
| } else { |
| DBF_EVENT(4, "tape_free_device(%p)\n", device); |
| kfree(device->modeset_byte); |
| kfree(device); |
| } |
| } |
| |
| return NULL; |
| } |
| |
| /* |
| * Find tape device by a device index. |
| */ |
| struct tape_device * |
| tape_get_device(int devindex) |
| { |
| struct tape_device *device, *tmp; |
| |
| device = ERR_PTR(-ENODEV); |
| read_lock(&tape_device_lock); |
| list_for_each_entry(tmp, &tape_device_list, node) { |
| if (tmp->first_minor / TAPE_MINORS_PER_DEV == devindex) { |
| device = tape_get_device_reference(tmp); |
| break; |
| } |
| } |
| read_unlock(&tape_device_lock); |
| return device; |
| } |
| |
| /* |
| * Driverfs tape probe function. |
| */ |
| int |
| tape_generic_probe(struct ccw_device *cdev) |
| { |
| struct tape_device *device; |
| int ret; |
| |
| device = tape_alloc_device(); |
| if (IS_ERR(device)) |
| return -ENODEV; |
| ccw_device_set_options(cdev, CCWDEV_DO_PATHGROUP); |
| ret = sysfs_create_group(&cdev->dev.kobj, &tape_attr_group); |
| if (ret) { |
| tape_put_device(device); |
| PRINT_ERR("probe failed for tape device %s\n", cdev->dev.bus_id); |
| return ret; |
| } |
| cdev->dev.driver_data = device; |
| cdev->handler = __tape_do_irq; |
| device->cdev = cdev; |
| device->cdev_id = busid_to_int(cdev->dev.bus_id); |
| PRINT_INFO("tape device %s found\n", cdev->dev.bus_id); |
| return ret; |
| } |
| |
| static inline void |
| __tape_discard_requests(struct tape_device *device) |
| { |
| struct tape_request * request; |
| struct list_head * l, *n; |
| |
| list_for_each_safe(l, n, &device->req_queue) { |
| request = list_entry(l, struct tape_request, list); |
| if (request->status == TAPE_REQUEST_IN_IO) |
| request->status = TAPE_REQUEST_DONE; |
| list_del(&request->list); |
| |
| /* Decrease ref_count for removed request. */ |
| request->device = tape_put_device(device); |
| request->rc = -EIO; |
| if (request->callback != NULL) |
| request->callback(request, request->callback_data); |
| } |
| } |
| |
| /* |
| * Driverfs tape remove function. |
| * |
| * This function is called whenever the common I/O layer detects the device |
| * gone. This can happen at any time and we cannot refuse. |
| */ |
| void |
| tape_generic_remove(struct ccw_device *cdev) |
| { |
| struct tape_device * device; |
| |
| device = cdev->dev.driver_data; |
| if (!device) { |
| PRINT_ERR("No device pointer in tape_generic_remove!\n"); |
| return; |
| } |
| DBF_LH(3, "(%08x): tape_generic_remove(%p)\n", device->cdev_id, cdev); |
| |
| spin_lock_irq(get_ccwdev_lock(device->cdev)); |
| switch (device->tape_state) { |
| case TS_INIT: |
| tape_state_set(device, TS_NOT_OPER); |
| case TS_NOT_OPER: |
| /* |
| * Nothing to do. |
| */ |
| spin_unlock_irq(get_ccwdev_lock(device->cdev)); |
| break; |
| case TS_UNUSED: |
| /* |
| * Need only to release the device. |
| */ |
| tape_state_set(device, TS_NOT_OPER); |
| spin_unlock_irq(get_ccwdev_lock(device->cdev)); |
| tape_cleanup_device(device); |
| break; |
| default: |
| /* |
| * There may be requests on the queue. We will not get |
| * an interrupt for a request that was running. So we |
| * just post them all as I/O errors. |
| */ |
| DBF_EVENT(3, "(%08x): Drive in use vanished!\n", |
| device->cdev_id); |
| PRINT_WARN("(%s): Drive in use vanished - " |
| "expect trouble!\n", |
| device->cdev->dev.bus_id); |
| PRINT_WARN("State was %i\n", device->tape_state); |
| tape_state_set(device, TS_NOT_OPER); |
| __tape_discard_requests(device); |
| spin_unlock_irq(get_ccwdev_lock(device->cdev)); |
| tape_cleanup_device(device); |
| } |
| |
| if (cdev->dev.driver_data != NULL) { |
| sysfs_remove_group(&cdev->dev.kobj, &tape_attr_group); |
| cdev->dev.driver_data = tape_put_device(cdev->dev.driver_data); |
| } |
| } |
| |
| /* |
| * Allocate a new tape ccw request |
| */ |
| struct tape_request * |
| tape_alloc_request(int cplength, int datasize) |
| { |
| struct tape_request *request; |
| |
| if (datasize > PAGE_SIZE || (cplength*sizeof(struct ccw1)) > PAGE_SIZE) |
| BUG(); |
| |
| DBF_LH(6, "tape_alloc_request(%d, %d)\n", cplength, datasize); |
| |
| request = kzalloc(sizeof(struct tape_request), GFP_KERNEL); |
| if (request == NULL) { |
| DBF_EXCEPTION(1, "cqra nomem\n"); |
| return ERR_PTR(-ENOMEM); |
| } |
| /* allocate channel program */ |
| if (cplength > 0) { |
| request->cpaddr = kcalloc(cplength, sizeof(struct ccw1), |
| GFP_ATOMIC | GFP_DMA); |
| if (request->cpaddr == NULL) { |
| DBF_EXCEPTION(1, "cqra nomem\n"); |
| kfree(request); |
| return ERR_PTR(-ENOMEM); |
| } |
| } |
| /* alloc small kernel buffer */ |
| if (datasize > 0) { |
| request->cpdata = kzalloc(datasize, GFP_KERNEL | GFP_DMA); |
| if (request->cpdata == NULL) { |
| DBF_EXCEPTION(1, "cqra nomem\n"); |
| kfree(request->cpaddr); |
| kfree(request); |
| return ERR_PTR(-ENOMEM); |
| } |
| } |
| DBF_LH(6, "New request %p(%p/%p)\n", request, request->cpaddr, |
| request->cpdata); |
| |
| return request; |
| } |
| |
| /* |
| * Free tape ccw request |
| */ |
| void |
| tape_free_request (struct tape_request * request) |
| { |
| DBF_LH(6, "Free request %p\n", request); |
| |
| if (request->device != NULL) { |
| request->device = tape_put_device(request->device); |
| } |
| kfree(request->cpdata); |
| kfree(request->cpaddr); |
| kfree(request); |
| } |
| |
| static inline int |
| __tape_start_io(struct tape_device *device, struct tape_request *request) |
| { |
| int rc; |
| |
| #ifdef CONFIG_S390_TAPE_BLOCK |
| if (request->op == TO_BLOCK) |
| device->discipline->check_locate(device, request); |
| #endif |
| rc = ccw_device_start( |
| device->cdev, |
| request->cpaddr, |
| (unsigned long) request, |
| 0x00, |
| request->options |
| ); |
| if (rc == 0) { |
| request->status = TAPE_REQUEST_IN_IO; |
| } else if (rc == -EBUSY) { |
| /* The common I/O subsystem is currently busy. Retry later. */ |
| request->status = TAPE_REQUEST_QUEUED; |
| schedule_delayed_work(&device->tape_dnr, 0); |
| rc = 0; |
| } else { |
| /* Start failed. Remove request and indicate failure. */ |
| DBF_EVENT(1, "tape: start request failed with RC = %i\n", rc); |
| } |
| return rc; |
| } |
| |
| static inline void |
| __tape_start_next_request(struct tape_device *device) |
| { |
| struct list_head *l, *n; |
| struct tape_request *request; |
| int rc; |
| |
| DBF_LH(6, "__tape_start_next_request(%p)\n", device); |
| /* |
| * Try to start each request on request queue until one is |
| * started successful. |
| */ |
| list_for_each_safe(l, n, &device->req_queue) { |
| request = list_entry(l, struct tape_request, list); |
| |
| /* |
| * Avoid race condition if bottom-half was triggered more than |
| * once. |
| */ |
| if (request->status == TAPE_REQUEST_IN_IO) |
| return; |
| /* |
| * Request has already been stopped. We have to wait until |
| * the request is removed from the queue in the interrupt |
| * handling. |
| */ |
| if (request->status == TAPE_REQUEST_DONE) |
| return; |
| |
| /* |
| * We wanted to cancel the request but the common I/O layer |
| * was busy at that time. This can only happen if this |
| * function is called by delayed_next_request. |
| * Otherwise we start the next request on the queue. |
| */ |
| if (request->status == TAPE_REQUEST_CANCEL) { |
| rc = __tape_cancel_io(device, request); |
| } else { |
| rc = __tape_start_io(device, request); |
| } |
| if (rc == 0) |
| return; |
| |
| /* Set ending status. */ |
| request->rc = rc; |
| request->status = TAPE_REQUEST_DONE; |
| |
| /* Remove from request queue. */ |
| list_del(&request->list); |
| |
| /* Do callback. */ |
| if (request->callback != NULL) |
| request->callback(request, request->callback_data); |
| } |
| } |
| |
| static void |
| tape_delayed_next_request(struct work_struct *work) |
| { |
| struct tape_device *device = |
| container_of(work, struct tape_device, tape_dnr.work); |
| |
| DBF_LH(6, "tape_delayed_next_request(%p)\n", device); |
| spin_lock_irq(get_ccwdev_lock(device->cdev)); |
| __tape_start_next_request(device); |
| spin_unlock_irq(get_ccwdev_lock(device->cdev)); |
| } |
| |
| static inline void |
| __tape_end_request( |
| struct tape_device * device, |
| struct tape_request * request, |
| int rc) |
| { |
| DBF_LH(6, "__tape_end_request(%p, %p, %i)\n", device, request, rc); |
| if (request) { |
| request->rc = rc; |
| request->status = TAPE_REQUEST_DONE; |
| |
| /* Remove from request queue. */ |
| list_del(&request->list); |
| |
| /* Do callback. */ |
| if (request->callback != NULL) |
| request->callback(request, request->callback_data); |
| } |
| |
| /* Start next request. */ |
| if (!list_empty(&device->req_queue)) |
| __tape_start_next_request(device); |
| } |
| |
| /* |
| * Write sense data to console/dbf |
| */ |
| void |
| tape_dump_sense(struct tape_device* device, struct tape_request *request, |
| struct irb *irb) |
| { |
| unsigned int *sptr; |
| |
| PRINT_INFO("-------------------------------------------------\n"); |
| PRINT_INFO("DSTAT : %02x CSTAT: %02x CPA: %04x\n", |
| irb->scsw.dstat, irb->scsw.cstat, irb->scsw.cpa); |
| PRINT_INFO("DEVICE: %s\n", device->cdev->dev.bus_id); |
| if (request != NULL) |
| PRINT_INFO("OP : %s\n", tape_op_verbose[request->op]); |
| |
| sptr = (unsigned int *) irb->ecw; |
| PRINT_INFO("Sense data: %08X %08X %08X %08X \n", |
| sptr[0], sptr[1], sptr[2], sptr[3]); |
| PRINT_INFO("Sense data: %08X %08X %08X %08X \n", |
| sptr[4], sptr[5], sptr[6], sptr[7]); |
| PRINT_INFO("--------------------------------------------------\n"); |
| } |
| |
| /* |
| * Write sense data to dbf |
| */ |
| void |
| tape_dump_sense_dbf(struct tape_device *device, struct tape_request *request, |
| struct irb *irb) |
| { |
| unsigned int *sptr; |
| const char* op; |
| |
| if (request != NULL) |
| op = tape_op_verbose[request->op]; |
| else |
| op = "---"; |
| DBF_EVENT(3, "DSTAT : %02x CSTAT: %02x\n", |
| irb->scsw.dstat,irb->scsw.cstat); |
| DBF_EVENT(3, "DEVICE: %08x OP\t: %s\n", device->cdev_id, op); |
| sptr = (unsigned int *) irb->ecw; |
| DBF_EVENT(3, "%08x %08x\n", sptr[0], sptr[1]); |
| DBF_EVENT(3, "%08x %08x\n", sptr[2], sptr[3]); |
| DBF_EVENT(3, "%08x %08x\n", sptr[4], sptr[5]); |
| DBF_EVENT(3, "%08x %08x\n", sptr[6], sptr[7]); |
| } |
| |
| /* |
| * I/O helper function. Adds the request to the request queue |
| * and starts it if the tape is idle. Has to be called with |
| * the device lock held. |
| */ |
| static inline int |
| __tape_start_request(struct tape_device *device, struct tape_request *request) |
| { |
| int rc; |
| |
| switch (request->op) { |
| case TO_MSEN: |
| case TO_ASSIGN: |
| case TO_UNASSIGN: |
| case TO_READ_ATTMSG: |
| if (device->tape_state == TS_INIT) |
| break; |
| if (device->tape_state == TS_UNUSED) |
| break; |
| default: |
| if (device->tape_state == TS_BLKUSE) |
| break; |
| if (device->tape_state != TS_IN_USE) |
| return -ENODEV; |
| } |
| |
| /* Increase use count of device for the added request. */ |
| request->device = tape_get_device_reference(device); |
| |
| if (list_empty(&device->req_queue)) { |
| /* No other requests are on the queue. Start this one. */ |
| rc = __tape_start_io(device, request); |
| if (rc) |
| return rc; |
| |
| DBF_LH(5, "Request %p added for execution.\n", request); |
| list_add(&request->list, &device->req_queue); |
| } else { |
| DBF_LH(5, "Request %p add to queue.\n", request); |
| request->status = TAPE_REQUEST_QUEUED; |
| list_add_tail(&request->list, &device->req_queue); |
| } |
| return 0; |
| } |
| |
| /* |
| * Add the request to the request queue, try to start it if the |
| * tape is idle. Return without waiting for end of i/o. |
| */ |
| int |
| tape_do_io_async(struct tape_device *device, struct tape_request *request) |
| { |
| int rc; |
| |
| DBF_LH(6, "tape_do_io_async(%p, %p)\n", device, request); |
| |
| spin_lock_irq(get_ccwdev_lock(device->cdev)); |
| /* Add request to request queue and try to start it. */ |
| rc = __tape_start_request(device, request); |
| spin_unlock_irq(get_ccwdev_lock(device->cdev)); |
| return rc; |
| } |
| |
| /* |
| * tape_do_io/__tape_wake_up |
| * Add the request to the request queue, try to start it if the |
| * tape is idle and wait uninterruptible for its completion. |
| */ |
| static void |
| __tape_wake_up(struct tape_request *request, void *data) |
| { |
| request->callback = NULL; |
| wake_up((wait_queue_head_t *) data); |
| } |
| |
| int |
| tape_do_io(struct tape_device *device, struct tape_request *request) |
| { |
| wait_queue_head_t wq; |
| int rc; |
| |
| init_waitqueue_head(&wq); |
| spin_lock_irq(get_ccwdev_lock(device->cdev)); |
| /* Setup callback */ |
| request->callback = __tape_wake_up; |
| request->callback_data = &wq; |
| /* Add request to request queue and try to start it. */ |
| rc = __tape_start_request(device, request); |
| spin_unlock_irq(get_ccwdev_lock(device->cdev)); |
| if (rc) |
| return rc; |
| /* Request added to the queue. Wait for its completion. */ |
| wait_event(wq, (request->callback == NULL)); |
| /* Get rc from request */ |
| return request->rc; |
| } |
| |
| /* |
| * tape_do_io_interruptible/__tape_wake_up_interruptible |
| * Add the request to the request queue, try to start it if the |
| * tape is idle and wait uninterruptible for its completion. |
| */ |
| static void |
| __tape_wake_up_interruptible(struct tape_request *request, void *data) |
| { |
| request->callback = NULL; |
| wake_up_interruptible((wait_queue_head_t *) data); |
| } |
| |
| int |
| tape_do_io_interruptible(struct tape_device *device, |
| struct tape_request *request) |
| { |
| wait_queue_head_t wq; |
| int rc; |
| |
| init_waitqueue_head(&wq); |
| spin_lock_irq(get_ccwdev_lock(device->cdev)); |
| /* Setup callback */ |
| request->callback = __tape_wake_up_interruptible; |
| request->callback_data = &wq; |
| rc = __tape_start_request(device, request); |
| spin_unlock_irq(get_ccwdev_lock(device->cdev)); |
| if (rc) |
| return rc; |
| /* Request added to the queue. Wait for its completion. */ |
| rc = wait_event_interruptible(wq, (request->callback == NULL)); |
| if (rc != -ERESTARTSYS) |
| /* Request finished normally. */ |
| return request->rc; |
| |
| /* Interrupted by a signal. We have to stop the current request. */ |
| spin_lock_irq(get_ccwdev_lock(device->cdev)); |
| rc = __tape_cancel_io(device, request); |
| spin_unlock_irq(get_ccwdev_lock(device->cdev)); |
| if (rc == 0) { |
| /* Wait for the interrupt that acknowledges the halt. */ |
| do { |
| rc = wait_event_interruptible( |
| wq, |
| (request->callback == NULL) |
| ); |
| } while (rc == -ERESTARTSYS); |
| |
| DBF_EVENT(3, "IO stopped on %08x\n", device->cdev_id); |
| rc = -ERESTARTSYS; |
| } |
| return rc; |
| } |
| |
| /* |
| * Stop running ccw. |
| */ |
| int |
| tape_cancel_io(struct tape_device *device, struct tape_request *request) |
| { |
| int rc; |
| |
| spin_lock_irq(get_ccwdev_lock(device->cdev)); |
| rc = __tape_cancel_io(device, request); |
| spin_unlock_irq(get_ccwdev_lock(device->cdev)); |
| return rc; |
| } |
| |
| /* |
| * Tape interrupt routine, called from the ccw_device layer |
| */ |
| static void |
| __tape_do_irq (struct ccw_device *cdev, unsigned long intparm, struct irb *irb) |
| { |
| struct tape_device *device; |
| struct tape_request *request; |
| int rc; |
| |
| device = (struct tape_device *) cdev->dev.driver_data; |
| if (device == NULL) { |
| PRINT_ERR("could not get device structure for %s " |
| "in interrupt\n", cdev->dev.bus_id); |
| return; |
| } |
| request = (struct tape_request *) intparm; |
| |
| DBF_LH(6, "__tape_do_irq(device=%p, request=%p)\n", device, request); |
| |
| /* On special conditions irb is an error pointer */ |
| if (IS_ERR(irb)) { |
| /* FIXME: What to do with the request? */ |
| switch (PTR_ERR(irb)) { |
| case -ETIMEDOUT: |
| PRINT_WARN("(%s): Request timed out\n", |
| cdev->dev.bus_id); |
| case -EIO: |
| __tape_end_request(device, request, -EIO); |
| break; |
| default: |
| PRINT_ERR("(%s): Unexpected i/o error %li\n", |
| cdev->dev.bus_id, |
| PTR_ERR(irb)); |
| } |
| return; |
| } |
| |
| /* |
| * If the condition code is not zero and the start function bit is |
| * still set, this is an deferred error and the last start I/O did |
| * not succeed. At this point the condition that caused the deferred |
| * error might still apply. So we just schedule the request to be |
| * started later. |
| */ |
| if (irb->scsw.cc != 0 && (irb->scsw.fctl & SCSW_FCTL_START_FUNC) && |
| (request->status == TAPE_REQUEST_IN_IO)) { |
| DBF_EVENT(3,"(%08x): deferred cc=%i, fctl=%i. restarting\n", |
| device->cdev_id, irb->scsw.cc, irb->scsw.fctl); |
| request->status = TAPE_REQUEST_QUEUED; |
| schedule_delayed_work(&device->tape_dnr, HZ); |
| return; |
| } |
| |
| /* May be an unsolicited irq */ |
| if(request != NULL) |
| request->rescnt = irb->scsw.count; |
| |
| if (irb->scsw.dstat != 0x0c) { |
| /* Set the 'ONLINE' flag depending on sense byte 1 */ |
| if(*(((__u8 *) irb->ecw) + 1) & SENSE_DRIVE_ONLINE) |
| device->tape_generic_status |= GMT_ONLINE(~0); |
| else |
| device->tape_generic_status &= ~GMT_ONLINE(~0); |
| |
| /* |
| * Any request that does not come back with channel end |
| * and device end is unusual. Log the sense data. |
| */ |
| DBF_EVENT(3,"-- Tape Interrupthandler --\n"); |
| tape_dump_sense_dbf(device, request, irb); |
| } else { |
| /* Upon normal completion the device _is_ online */ |
| device->tape_generic_status |= GMT_ONLINE(~0); |
| } |
| if (device->tape_state == TS_NOT_OPER) { |
| DBF_EVENT(6, "tape:device is not operational\n"); |
| return; |
| } |
| |
| /* |
| * Request that were canceled still come back with an interrupt. |
| * To detect these request the state will be set to TAPE_REQUEST_DONE. |
| */ |
| if(request != NULL && request->status == TAPE_REQUEST_DONE) { |
| __tape_end_request(device, request, -EIO); |
| return; |
| } |
| |
| rc = device->discipline->irq(device, request, irb); |
| /* |
| * rc < 0 : request finished unsuccessfully. |
| * rc == TAPE_IO_SUCCESS: request finished successfully. |
| * rc == TAPE_IO_PENDING: request is still running. Ignore rc. |
| * rc == TAPE_IO_RETRY: request finished but needs another go. |
| * rc == TAPE_IO_STOP: request needs to get terminated. |
| */ |
| switch (rc) { |
| case TAPE_IO_SUCCESS: |
| /* Upon normal completion the device _is_ online */ |
| device->tape_generic_status |= GMT_ONLINE(~0); |
| __tape_end_request(device, request, rc); |
| break; |
| case TAPE_IO_PENDING: |
| break; |
| case TAPE_IO_RETRY: |
| rc = __tape_start_io(device, request); |
| if (rc) |
| __tape_end_request(device, request, rc); |
| break; |
| case TAPE_IO_STOP: |
| rc = __tape_cancel_io(device, request); |
| if (rc) |
| __tape_end_request(device, request, rc); |
| break; |
| default: |
| if (rc > 0) { |
| DBF_EVENT(6, "xunknownrc\n"); |
| PRINT_ERR("Invalid return code from discipline " |
| "interrupt function.\n"); |
| __tape_end_request(device, request, -EIO); |
| } else { |
| __tape_end_request(device, request, rc); |
| } |
| break; |
| } |
| } |
| |
| /* |
| * Tape device open function used by tape_char & tape_block frontends. |
| */ |
| int |
| tape_open(struct tape_device *device) |
| { |
| int rc; |
| |
| spin_lock(get_ccwdev_lock(device->cdev)); |
| if (device->tape_state == TS_NOT_OPER) { |
| DBF_EVENT(6, "TAPE:nodev\n"); |
| rc = -ENODEV; |
| } else if (device->tape_state == TS_IN_USE) { |
| DBF_EVENT(6, "TAPE:dbusy\n"); |
| rc = -EBUSY; |
| } else if (device->tape_state == TS_BLKUSE) { |
| DBF_EVENT(6, "TAPE:dbusy\n"); |
| rc = -EBUSY; |
| } else if (device->discipline != NULL && |
| !try_module_get(device->discipline->owner)) { |
| DBF_EVENT(6, "TAPE:nodisc\n"); |
| rc = -ENODEV; |
| } else { |
| tape_state_set(device, TS_IN_USE); |
| rc = 0; |
| } |
| spin_unlock(get_ccwdev_lock(device->cdev)); |
| return rc; |
| } |
| |
| /* |
| * Tape device release function used by tape_char & tape_block frontends. |
| */ |
| int |
| tape_release(struct tape_device *device) |
| { |
| spin_lock(get_ccwdev_lock(device->cdev)); |
| if (device->tape_state == TS_IN_USE) |
| tape_state_set(device, TS_UNUSED); |
| module_put(device->discipline->owner); |
| spin_unlock(get_ccwdev_lock(device->cdev)); |
| return 0; |
| } |
| |
| /* |
| * Execute a magnetic tape command a number of times. |
| */ |
| int |
| tape_mtop(struct tape_device *device, int mt_op, int mt_count) |
| { |
| tape_mtop_fn fn; |
| int rc; |
| |
| DBF_EVENT(6, "TAPE:mtio\n"); |
| DBF_EVENT(6, "TAPE:ioop: %x\n", mt_op); |
| DBF_EVENT(6, "TAPE:arg: %x\n", mt_count); |
| |
| if (mt_op < 0 || mt_op >= TAPE_NR_MTOPS) |
| return -EINVAL; |
| fn = device->discipline->mtop_array[mt_op]; |
| if (fn == NULL) |
| return -EINVAL; |
| |
| /* We assume that the backends can handle count up to 500. */ |
| if (mt_op == MTBSR || mt_op == MTFSR || mt_op == MTFSF || |
| mt_op == MTBSF || mt_op == MTFSFM || mt_op == MTBSFM) { |
| rc = 0; |
| for (; mt_count > 500; mt_count -= 500) |
| if ((rc = fn(device, 500)) != 0) |
| break; |
| if (rc == 0) |
| rc = fn(device, mt_count); |
| } else |
| rc = fn(device, mt_count); |
| return rc; |
| |
| } |
| |
| /* |
| * Tape init function. |
| */ |
| static int |
| tape_init (void) |
| { |
| TAPE_DBF_AREA = debug_register ( "tape", 2, 2, 4*sizeof(long)); |
| debug_register_view(TAPE_DBF_AREA, &debug_sprintf_view); |
| #ifdef DBF_LIKE_HELL |
| debug_set_level(TAPE_DBF_AREA, 6); |
| #endif |
| DBF_EVENT(3, "tape init\n"); |
| tape_proc_init(); |
| tapechar_init (); |
| tapeblock_init (); |
| return 0; |
| } |
| |
| /* |
| * Tape exit function. |
| */ |
| static void |
| tape_exit(void) |
| { |
| DBF_EVENT(6, "tape exit\n"); |
| |
| /* Get rid of the frontends */ |
| tapechar_exit(); |
| tapeblock_exit(); |
| tape_proc_cleanup(); |
| debug_unregister (TAPE_DBF_AREA); |
| } |
| |
| MODULE_AUTHOR("(C) 2001 IBM Deutschland Entwicklung GmbH by Carsten Otte and " |
| "Michael Holzheu (cotte@de.ibm.com,holzheu@de.ibm.com)"); |
| MODULE_DESCRIPTION("Linux on zSeries channel attached tape device driver"); |
| MODULE_LICENSE("GPL"); |
| |
| module_init(tape_init); |
| module_exit(tape_exit); |
| |
| EXPORT_SYMBOL(tape_generic_remove); |
| EXPORT_SYMBOL(tape_generic_probe); |
| EXPORT_SYMBOL(tape_generic_online); |
| EXPORT_SYMBOL(tape_generic_offline); |
| EXPORT_SYMBOL(tape_put_device); |
| EXPORT_SYMBOL(tape_get_device_reference); |
| EXPORT_SYMBOL(tape_state_verbose); |
| EXPORT_SYMBOL(tape_op_verbose); |
| EXPORT_SYMBOL(tape_state_set); |
| EXPORT_SYMBOL(tape_med_state_set); |
| EXPORT_SYMBOL(tape_alloc_request); |
| EXPORT_SYMBOL(tape_free_request); |
| EXPORT_SYMBOL(tape_dump_sense); |
| EXPORT_SYMBOL(tape_dump_sense_dbf); |
| EXPORT_SYMBOL(tape_do_io); |
| EXPORT_SYMBOL(tape_do_io_async); |
| EXPORT_SYMBOL(tape_do_io_interruptible); |
| EXPORT_SYMBOL(tape_cancel_io); |
| EXPORT_SYMBOL(tape_mtop); |