From 9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 Mon Sep 17 00:00:00 2001 From: Yunhong Jiang Date: Tue, 4 Aug 2015 12:17:53 -0700 Subject: Add the rt linux 4.1.3-rt3 as base Import the rt linux 4.1.3-rt3 as OPNFV kvm base. It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and the base is: commit 0917f823c59692d751951bf5ea699a2d1e2f26a2 Author: Sebastian Andrzej Siewior Date: Sat Jul 25 12:13:34 2015 +0200 Prepare v4.1.3-rt3 Signed-off-by: Sebastian Andrzej Siewior We lose all the git history this way and it's not good. We should apply another opnfv project repo in future. Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423 Signed-off-by: Yunhong Jiang --- kernel/drivers/s390/char/tape_core.c | 1379 ++++++++++++++++++++++++++++++++++ 1 file changed, 1379 insertions(+) create mode 100644 kernel/drivers/s390/char/tape_core.c (limited to 'kernel/drivers/s390/char/tape_core.c') diff --git a/kernel/drivers/s390/char/tape_core.c b/kernel/drivers/s390/char/tape_core.c new file mode 100644 index 000000000..f3b5123fa --- /dev/null +++ b/kernel/drivers/s390/char/tape_core.c @@ -0,0 +1,1379 @@ +/* + * basic function of the tape device driver + * + * S390 and zSeries version + * Copyright IBM Corp. 2001, 2009 + * Author(s): Carsten Otte + * Michael Holzheu + * Tuan Ngo-Anh + * Martin Schwidefsky + * Stefan Bader + */ + +#define KMSG_COMPONENT "tape" +#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt + +#include +#include // for kernel parameters +#include // for requesting modules +#include // for locks +#include +#include +#include + +#include // for variable types + +#define TAPE_DBF_AREA tape_core_dbf + +#include "tape.h" +#include "tape_std.h" + +#define LONG_BUSY_TIMEOUT 180 /* seconds */ + +static void __tape_do_irq (struct ccw_device *, unsigned long, struct irb *); +static void tape_delayed_next_request(struct work_struct *); +static void tape_long_busy_timeout(unsigned long data); + +/* + * 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 LIST_HEAD(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", [TO_CRYPT_ON] = "CON", + [TO_CRYPT_OFF] = "COF", [TO_KEKL_SET] = "KLS", + [TO_KEKL_QUERY] = "KLQ",[TO_RDC] = "RDC", +}; + +static int devid_to_int(struct ccw_dev_id *dev_id) +{ + return dev_id->devno + (dev_id->ssid << 16); +} + +/* + * 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 = dev_get_drvdata(dev); + 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 = dev_get_drvdata(dev); + 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 = dev_get_drvdata(dev); + 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 = dev_get_drvdata(dev); + 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 = dev_get_drvdata(dev); + + 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); +} + +struct tape_med_state_work_data { + struct tape_device *device; + enum tape_medium_state state; + struct work_struct work; +}; + +static void +tape_med_state_work_handler(struct work_struct *work) +{ + static char env_state_loaded[] = "MEDIUM_STATE=LOADED"; + static char env_state_unloaded[] = "MEDIUM_STATE=UNLOADED"; + struct tape_med_state_work_data *p = + container_of(work, struct tape_med_state_work_data, work); + struct tape_device *device = p->device; + char *envp[] = { NULL, NULL }; + + switch (p->state) { + case MS_UNLOADED: + pr_info("%s: The tape cartridge has been successfully " + "unloaded\n", dev_name(&device->cdev->dev)); + envp[0] = env_state_unloaded; + kobject_uevent_env(&device->cdev->dev.kobj, KOBJ_CHANGE, envp); + break; + case MS_LOADED: + pr_info("%s: A tape cartridge has been mounted\n", + dev_name(&device->cdev->dev)); + envp[0] = env_state_loaded; + kobject_uevent_env(&device->cdev->dev.kobj, KOBJ_CHANGE, envp); + break; + default: + break; + } + tape_put_device(device); + kfree(p); +} + +static void +tape_med_state_work(struct tape_device *device, enum tape_medium_state state) +{ + struct tape_med_state_work_data *p; + + p = kzalloc(sizeof(*p), GFP_ATOMIC); + if (p) { + INIT_WORK(&p->work, tape_med_state_work_handler); + p->device = tape_get_device(device); + p->state = state; + schedule_work(&p->work); + } +} + +void +tape_med_state_set(struct tape_device *device, enum tape_medium_state newstate) +{ + enum tape_medium_state oldstate; + + oldstate = device->medium_state; + if (oldstate == newstate) + return; + device->medium_state = newstate; + switch(newstate){ + case MS_UNLOADED: + device->tape_generic_status |= GMT_DR_OPEN(~0); + if (oldstate == MS_LOADED) + tape_med_state_work(device, MS_UNLOADED); + break; + case MS_LOADED: + device->tape_generic_status &= ~GMT_DR_OPEN(~0); + if (oldstate == MS_UNLOADED) + tape_med_state_work(device, MS_LOADED); + break; + default: + break; + } + wake_up(&device->state_change_wq); +} + +/* + * Stop running ccw. Has to be called with the device lock held. + */ +static 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; + } + + init_timer(&device->lb_timeout); + device->lb_timeout.function = tape_long_busy_timeout; + + /* Let the discipline have a go at the device. */ + device->discipline = discipline; + if (!try_module_get(discipline->owner)) { + 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; + + tape_state_set(device, TS_UNUSED); + + DBF_LH(3, "(%08x): Drive set online\n", device->cdev_id); + + return 0; + +out_minor: + tape_remove_minor(device); +out_discipline: + device->discipline->cleanup_device(device); + device->discipline = NULL; +out: + module_put(discipline->owner); + return rc; +} + +static void +tape_cleanup_device(struct tape_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); +} + +/* + * Suspend device. + * + * Called by the common I/O layer if the drive should be suspended on user + * request. We refuse to suspend if the device is loaded or in use for the + * following reason: + * While the Linux guest is suspended, it might be logged off which causes + * devices to be detached. Tape devices are automatically rewound and unloaded + * during DETACH processing (unless the tape device was attached with the + * NOASSIGN or MULTIUSER option). After rewind/unload, there is no way to + * resume the original state of the tape device, since we would need to + * manually re-load the cartridge which was active at suspend time. + */ +int tape_generic_pm_suspend(struct ccw_device *cdev) +{ + struct tape_device *device; + + device = dev_get_drvdata(&cdev->dev); + if (!device) { + return -ENODEV; + } + + DBF_LH(3, "(%08x): tape_generic_pm_suspend(%p)\n", + device->cdev_id, device); + + if (device->medium_state != MS_UNLOADED) { + pr_err("A cartridge is loaded in tape device %s, " + "refusing to suspend\n", dev_name(&cdev->dev)); + return -EBUSY; + } + + spin_lock_irq(get_ccwdev_lock(device->cdev)); + switch (device->tape_state) { + case TS_INIT: + case TS_NOT_OPER: + case TS_UNUSED: + spin_unlock_irq(get_ccwdev_lock(device->cdev)); + break; + default: + pr_err("Tape device %s is busy, refusing to " + "suspend\n", dev_name(&cdev->dev)); + spin_unlock_irq(get_ccwdev_lock(device->cdev)); + return -EBUSY; + } + + DBF_LH(3, "(%08x): Drive suspended.\n", device->cdev_id); + return 0; +} + +/* + * 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 ccw_device *cdev) +{ + struct tape_device *device; + + device = dev_get_drvdata(&cdev->dev); + if (!device) { + 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); + 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"); + 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"); + kfree(device); + return ERR_PTR(-ENOMEM); + } + mutex_init(&device->mutex); + INIT_LIST_HEAD(&device->req_queue); + INIT_LIST_HEAD(&device->node); + init_waitqueue_head(&device->state_change_wq); + init_waitqueue_head(&device->wait_queue); + 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(struct tape_device *device) +{ + int count; + + count = atomic_inc_return(&device->ref_count); + DBF_EVENT(4, "tape_get_device(%p) = %i\n", device, 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. + */ +void +tape_put_device(struct tape_device *device) +{ + int count; + + count = atomic_dec_return(&device->ref_count); + DBF_EVENT(4, "tape_put_device(%p) -> %i\n", device, count); + BUG_ON(count < 0); + if (count == 0) { + kfree(device->modeset_byte); + kfree(device); + } +} + +/* + * Find tape device by a device index. + */ +struct tape_device * +tape_find_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(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; + struct ccw_dev_id dev_id; + + device = tape_alloc_device(); + if (IS_ERR(device)) + return -ENODEV; + ccw_device_set_options(cdev, CCWDEV_DO_PATHGROUP | + CCWDEV_DO_MULTIPATH); + ret = sysfs_create_group(&cdev->dev.kobj, &tape_attr_group); + if (ret) { + tape_put_device(device); + return ret; + } + dev_set_drvdata(&cdev->dev, device); + cdev->handler = __tape_do_irq; + device->cdev = cdev; + ccw_device_get_id(cdev, &dev_id); + device->cdev_id = devid_to_int(&dev_id); + return ret; +} + +static 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 = NULL; + 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 = dev_get_drvdata(&cdev->dev); + if (!device) { + 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); + pr_warning("%s: A tape unit was detached while in " + "use\n", dev_name(&device->cdev->dev)); + tape_state_set(device, TS_NOT_OPER); + __tape_discard_requests(device); + spin_unlock_irq(get_ccwdev_lock(device->cdev)); + tape_cleanup_device(device); + } + + device = dev_get_drvdata(&cdev->dev); + if (device) { + sysfs_remove_group(&cdev->dev.kobj, &tape_attr_group); + dev_set_drvdata(&cdev->dev, NULL); + tape_put_device(device); + } +} + +/* + * Allocate a new tape ccw request + */ +struct tape_request * +tape_alloc_request(int cplength, int datasize) +{ + struct tape_request *request; + + BUG_ON(datasize > PAGE_SIZE || (cplength*sizeof(struct ccw1)) > PAGE_SIZE); + + 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) + tape_put_device(request->device); + kfree(request->cpdata); + kfree(request->cpaddr); + kfree(request); +} + +static int +__tape_start_io(struct tape_device *device, struct tape_request *request) +{ + int rc; + + 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 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 void tape_long_busy_timeout(unsigned long data) +{ + struct tape_request *request; + struct tape_device *device; + + device = (struct tape_device *) data; + spin_lock_irq(get_ccwdev_lock(device->cdev)); + request = list_entry(device->req_queue.next, struct tape_request, list); + BUG_ON(request->status != TAPE_REQUEST_LONG_BUSY); + DBF_LH(6, "%08x: Long busy timeout.\n", device->cdev_id); + __tape_start_next_request(device); + device->lb_timeout.data = 0UL; + tape_put_device(device); + spin_unlock_irq(get_ccwdev_lock(device->cdev)); +} + +static 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 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.cmd.dstat, irb->scsw.cmd.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 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: + case TO_RDC: + 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(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) +{ + int rc; + + spin_lock_irq(get_ccwdev_lock(device->cdev)); + /* Setup callback */ + request->callback = __tape_wake_up; + request->callback_data = &device->wait_queue; + /* 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(device->wait_queue, (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) +{ + int rc; + + spin_lock_irq(get_ccwdev_lock(device->cdev)); + /* Setup callback */ + request->callback = __tape_wake_up_interruptible; + request->callback_data = &device->wait_queue; + 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(device->wait_queue, + (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( + device->wait_queue, + (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 = dev_get_drvdata(&cdev->dev); + if (device == NULL) { + 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: + DBF_LH(1, "(%08x): Request timed out\n", + device->cdev_id); + case -EIO: + __tape_end_request(device, request, -EIO); + break; + default: + DBF_LH(1, "(%08x): Unexpected i/o error %li\n", + device->cdev_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.cmd.cc != 0 && + (irb->scsw.cmd.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.cmd.cc, irb->scsw.cmd.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.cmd.count; + else if ((irb->scsw.cmd.dstat == 0x85 || irb->scsw.cmd.dstat == 0x80) && + !list_empty(&device->req_queue)) { + /* Not Ready to Ready after long busy ? */ + struct tape_request *req; + req = list_entry(device->req_queue.next, + struct tape_request, list); + if (req->status == TAPE_REQUEST_LONG_BUSY) { + DBF_EVENT(3, "(%08x): del timer\n", device->cdev_id); + if (del_timer(&device->lb_timeout)) { + device->lb_timeout.data = 0UL; + tape_put_device(device); + __tape_start_next_request(device); + } + return; + } + } + if (irb->scsw.cmd.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_LONG_BUSY: + device->lb_timeout.data = + (unsigned long) tape_get_device(device); + device->lb_timeout.expires = jiffies + + LONG_BUSY_TIMEOUT * HZ; + DBF_EVENT(3, "(%08x): add timer\n", device->cdev_id); + add_timer(&device->lb_timeout); + request->status = TAPE_REQUEST_LONG_BUSY; + 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"); + __tape_end_request(device, request, -EIO); + } else { + __tape_end_request(device, request, rc); + } + break; + } +} + +/* + * Tape device open function used by tape_char frontend. + */ +int +tape_open(struct tape_device *device) +{ + int rc; + + spin_lock_irq(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_irq(get_ccwdev_lock(device->cdev)); + return rc; +} + +/* + * Tape device release function used by tape_char frontend. + */ +int +tape_release(struct tape_device *device) +{ + spin_lock_irq(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_irq(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 (); + return 0; +} + +/* + * Tape exit function. + */ +static void +tape_exit(void) +{ + DBF_EVENT(6, "tape exit\n"); + + /* Get rid of the frontends */ + tapechar_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_generic_pm_suspend); +EXPORT_SYMBOL(tape_put_device); +EXPORT_SYMBOL(tape_get_device); +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_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); -- cgit 1.2.3-korg