diff options
Diffstat (limited to 'drivers/s390/cio/scm.c')
| -rw-r--r-- | drivers/s390/cio/scm.c | 289 |
1 files changed, 289 insertions, 0 deletions
diff --git a/drivers/s390/cio/scm.c b/drivers/s390/cio/scm.c new file mode 100644 index 000000000..6bca1d545 --- /dev/null +++ b/drivers/s390/cio/scm.c @@ -0,0 +1,289 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Recognize and maintain s390 storage class memory. + * + * Copyright IBM Corp. 2012 + * Author(s): Sebastian Ott <sebott@linux.vnet.ibm.com> + */ + +#include <linux/device.h> +#include <linux/module.h> +#include <linux/mutex.h> +#include <linux/slab.h> +#include <linux/init.h> +#include <linux/err.h> +#include <asm/eadm.h> +#include "chsc.h" + +static struct device *scm_root; + +#define to_scm_dev(n) container_of(n, struct scm_device, dev) +#define to_scm_drv(d) container_of(d, struct scm_driver, drv) + +static int scmdev_probe(struct device *dev) +{ + struct scm_device *scmdev = to_scm_dev(dev); + struct scm_driver *scmdrv = to_scm_drv(dev->driver); + + return scmdrv->probe ? scmdrv->probe(scmdev) : -ENODEV; +} + +static int scmdev_remove(struct device *dev) +{ + struct scm_device *scmdev = to_scm_dev(dev); + struct scm_driver *scmdrv = to_scm_drv(dev->driver); + + return scmdrv->remove ? scmdrv->remove(scmdev) : -ENODEV; +} + +static int scmdev_uevent(struct device *dev, struct kobj_uevent_env *env) +{ + return add_uevent_var(env, "MODALIAS=scm:scmdev"); +} + +static struct bus_type scm_bus_type = { + .name = "scm", + .probe = scmdev_probe, + .remove = scmdev_remove, + .uevent = scmdev_uevent, +}; + +/** + * scm_driver_register() - register a scm driver + * @scmdrv: driver to be registered + */ +int scm_driver_register(struct scm_driver *scmdrv) +{ + struct device_driver *drv = &scmdrv->drv; + + drv->bus = &scm_bus_type; + + return driver_register(drv); +} +EXPORT_SYMBOL_GPL(scm_driver_register); + +/** + * scm_driver_unregister() - deregister a scm driver + * @scmdrv: driver to be deregistered + */ +void scm_driver_unregister(struct scm_driver *scmdrv) +{ + driver_unregister(&scmdrv->drv); +} +EXPORT_SYMBOL_GPL(scm_driver_unregister); + +void scm_irq_handler(struct aob *aob, blk_status_t error) +{ + struct aob_rq_header *aobrq = (void *) aob->request.data; + struct scm_device *scmdev = aobrq->scmdev; + struct scm_driver *scmdrv = to_scm_drv(scmdev->dev.driver); + + scmdrv->handler(scmdev, aobrq->data, error); +} +EXPORT_SYMBOL_GPL(scm_irq_handler); + +#define scm_attr(name) \ +static ssize_t show_##name(struct device *dev, \ + struct device_attribute *attr, char *buf) \ +{ \ + struct scm_device *scmdev = to_scm_dev(dev); \ + int ret; \ + \ + device_lock(dev); \ + ret = sprintf(buf, "%u\n", scmdev->attrs.name); \ + device_unlock(dev); \ + \ + return ret; \ +} \ +static DEVICE_ATTR(name, S_IRUGO, show_##name, NULL); + +scm_attr(persistence); +scm_attr(oper_state); +scm_attr(data_state); +scm_attr(rank); +scm_attr(release); +scm_attr(res_id); + +static struct attribute *scmdev_attrs[] = { + &dev_attr_persistence.attr, + &dev_attr_oper_state.attr, + &dev_attr_data_state.attr, + &dev_attr_rank.attr, + &dev_attr_release.attr, + &dev_attr_res_id.attr, + NULL, +}; + +static struct attribute_group scmdev_attr_group = { + .attrs = scmdev_attrs, +}; + +static const struct attribute_group *scmdev_attr_groups[] = { + &scmdev_attr_group, + NULL, +}; + +static void scmdev_release(struct device *dev) +{ + struct scm_device *scmdev = to_scm_dev(dev); + + kfree(scmdev); +} + +static void scmdev_setup(struct scm_device *scmdev, struct sale *sale, + unsigned int size, unsigned int max_blk_count) +{ + dev_set_name(&scmdev->dev, "%016llx", (unsigned long long) sale->sa); + scmdev->nr_max_block = max_blk_count; + scmdev->address = sale->sa; + scmdev->size = 1UL << size; + scmdev->attrs.rank = sale->rank; + scmdev->attrs.persistence = sale->p; + scmdev->attrs.oper_state = sale->op_state; + scmdev->attrs.data_state = sale->data_state; + scmdev->attrs.rank = sale->rank; + scmdev->attrs.release = sale->r; + scmdev->attrs.res_id = sale->rid; + scmdev->dev.parent = scm_root; + scmdev->dev.bus = &scm_bus_type; + scmdev->dev.release = scmdev_release; + scmdev->dev.groups = scmdev_attr_groups; +} + +/* + * Check for state-changes, notify the driver and userspace. + */ +static void scmdev_update(struct scm_device *scmdev, struct sale *sale) +{ + struct scm_driver *scmdrv; + bool changed; + + device_lock(&scmdev->dev); + changed = scmdev->attrs.rank != sale->rank || + scmdev->attrs.oper_state != sale->op_state; + scmdev->attrs.rank = sale->rank; + scmdev->attrs.oper_state = sale->op_state; + if (!scmdev->dev.driver) + goto out; + scmdrv = to_scm_drv(scmdev->dev.driver); + if (changed && scmdrv->notify) + scmdrv->notify(scmdev, SCM_CHANGE); +out: + device_unlock(&scmdev->dev); + if (changed) + kobject_uevent(&scmdev->dev.kobj, KOBJ_CHANGE); +} + +static int check_address(struct device *dev, void *data) +{ + struct scm_device *scmdev = to_scm_dev(dev); + struct sale *sale = data; + + return scmdev->address == sale->sa; +} + +static struct scm_device *scmdev_find(struct sale *sale) +{ + struct device *dev; + + dev = bus_find_device(&scm_bus_type, NULL, sale, check_address); + + return dev ? to_scm_dev(dev) : NULL; +} + +static int scm_add(struct chsc_scm_info *scm_info, size_t num) +{ + struct sale *sale, *scmal = scm_info->scmal; + struct scm_device *scmdev; + int ret; + + for (sale = scmal; sale < scmal + num; sale++) { + scmdev = scmdev_find(sale); + if (scmdev) { + scmdev_update(scmdev, sale); + /* Release reference from scm_find(). */ + put_device(&scmdev->dev); + continue; + } + scmdev = kzalloc(sizeof(*scmdev), GFP_KERNEL); + if (!scmdev) + return -ENODEV; + scmdev_setup(scmdev, sale, scm_info->is, scm_info->mbc); + ret = device_register(&scmdev->dev); + if (ret) { + /* Release reference from device_initialize(). */ + put_device(&scmdev->dev); + return ret; + } + } + + return 0; +} + +int scm_update_information(void) +{ + struct chsc_scm_info *scm_info; + u64 token = 0; + size_t num; + int ret; + + scm_info = (void *)__get_free_page(GFP_KERNEL | GFP_DMA); + if (!scm_info) + return -ENOMEM; + + do { + ret = chsc_scm_info(scm_info, token); + if (ret) + break; + + num = (scm_info->response.length - + (offsetof(struct chsc_scm_info, scmal) - + offsetof(struct chsc_scm_info, response)) + ) / sizeof(struct sale); + + ret = scm_add(scm_info, num); + if (ret) + break; + + token = scm_info->restok; + } while (token); + + free_page((unsigned long)scm_info); + + return ret; +} + +static int scm_dev_avail(struct device *dev, void *unused) +{ + struct scm_driver *scmdrv = to_scm_drv(dev->driver); + struct scm_device *scmdev = to_scm_dev(dev); + + if (dev->driver && scmdrv->notify) + scmdrv->notify(scmdev, SCM_AVAIL); + + return 0; +} + +int scm_process_availability_information(void) +{ + return bus_for_each_dev(&scm_bus_type, NULL, NULL, scm_dev_avail); +} + +static int __init scm_init(void) +{ + int ret; + + ret = bus_register(&scm_bus_type); + if (ret) + return ret; + + scm_root = root_device_register("scm"); + if (IS_ERR(scm_root)) { + bus_unregister(&scm_bus_type); + return PTR_ERR(scm_root); + } + + scm_update_information(); + return 0; +} +subsys_initcall_sync(scm_init); |