diff options
Diffstat (limited to 'drivers/scsi')
| -rw-r--r-- | drivers/scsi/Kconfig | 6 | ||||
| -rw-r--r-- | drivers/scsi/Makefile | 2 | ||||
| -rw-r--r-- | drivers/scsi/raid_class.c | 250 |
3 files changed, 258 insertions, 0 deletions
diff --git a/drivers/scsi/Kconfig b/drivers/scsi/Kconfig index 96df148ed969..68adc3cc8ad2 100644 --- a/drivers/scsi/Kconfig +++ b/drivers/scsi/Kconfig @@ -1,5 +1,11 @@ menu "SCSI device support" +config RAID_ATTRS + tristate "RAID Transport Class" + default n + ---help--- + Provides RAID + config SCSI tristate "SCSI device support" ---help--- diff --git a/drivers/scsi/Makefile b/drivers/scsi/Makefile index 3746fb9fa2f5..85f9e6bb34b9 100644 --- a/drivers/scsi/Makefile +++ b/drivers/scsi/Makefile @@ -22,6 +22,8 @@ subdir-$(CONFIG_PCMCIA) += pcmcia obj-$(CONFIG_SCSI) += scsi_mod.o +obj-$(CONFIG_RAID_ATTRS) += raid_class.o + # --- NOTE ORDERING HERE --- # For kernel non-modular link, transport attributes need to # be initialised before drivers diff --git a/drivers/scsi/raid_class.c b/drivers/scsi/raid_class.c new file mode 100644 index 000000000000..f1ea5027865f --- /dev/null +++ b/drivers/scsi/raid_class.c @@ -0,0 +1,250 @@ +/* + * RAID Attributes + */ +#include <linux/init.h> +#include <linux/module.h> +#include <linux/list.h> +#include <linux/raid_class.h> +#include <scsi/scsi_device.h> +#include <scsi/scsi_host.h> + +#define RAID_NUM_ATTRS 3 + +struct raid_internal { + struct raid_template r; + struct raid_function_template *f; + /* The actual attributes */ + struct class_device_attribute private_attrs[RAID_NUM_ATTRS]; + /* The array of null terminated pointers to attributes + * needed by scsi_sysfs.c */ + struct class_device_attribute *attrs[RAID_NUM_ATTRS + 1]; +}; + +struct raid_component { + struct list_head node; + struct device *dev; + int num; +}; + +#define to_raid_internal(tmpl) container_of(tmpl, struct raid_internal, r) + +#define tc_to_raid_internal(tcont) ({ \ + struct raid_template *r = \ + container_of(tcont, struct raid_template, raid_attrs); \ + to_raid_internal(r); \ +}) + +#define ac_to_raid_internal(acont) ({ \ + struct transport_container *tc = \ + container_of(acont, struct transport_container, ac); \ + tc_to_raid_internal(tc); \ +}) + +#define class_device_to_raid_internal(cdev) ({ \ + struct attribute_container *ac = \ + attribute_container_classdev_to_container(cdev); \ + ac_to_raid_internal(ac); \ +}) + + +static int raid_match(struct attribute_container *cont, struct device *dev) +{ + /* We have to look for every subsystem that could house + * emulated RAID devices, so start with SCSI */ + struct raid_internal *i = ac_to_raid_internal(cont); + + if (scsi_is_sdev_device(dev)) { + struct scsi_device *sdev = to_scsi_device(dev); + + if (i->f->cookie != sdev->host->hostt) + return 0; + + return i->f->is_raid(dev); + } + /* FIXME: look at other subsystems too */ + return 0; +} + +static int raid_setup(struct transport_container *tc, struct device *dev, + struct class_device *cdev) +{ + struct raid_data *rd; + + BUG_ON(class_get_devdata(cdev)); + + rd = kmalloc(sizeof(*rd), GFP_KERNEL); + if (!rd) + return -ENOMEM; + + memset(rd, 0, sizeof(*rd)); + INIT_LIST_HEAD(&rd->component_list); + class_set_devdata(cdev, rd); + + return 0; +} + +static int raid_remove(struct transport_container *tc, struct device *dev, + struct class_device *cdev) +{ + struct raid_data *rd = class_get_devdata(cdev); + struct raid_component *rc, *next; + class_set_devdata(cdev, NULL); + list_for_each_entry_safe(rc, next, &rd->component_list, node) { + char buf[40]; + snprintf(buf, sizeof(buf), "component-%d", rc->num); + list_del(&rc->node); + sysfs_remove_link(&cdev->kobj, buf); + kfree(rc); + } + kfree(class_get_devdata(cdev)); + return 0; +} + +static DECLARE_TRANSPORT_CLASS(raid_class, + "raid_devices", + raid_setup, + raid_remove, + NULL); + +static struct { + enum raid_state value; + char *name; +} raid_states[] = { + { RAID_ACTIVE, "active" }, + { RAID_DEGRADED, "degraded" }, + { RAID_RESYNCING, "resyncing" }, + { RAID_OFFLINE, "offline" }, +}; + +static const char *raid_state_name(enum raid_state state) +{ + int i; + char *name = NULL; + + for (i = 0; i < sizeof(raid_states)/sizeof(raid_states[0]); i++) { + if (raid_states[i].value == state) { + name = raid_states[i].name; + break; + } + } + return name; +} + + +#define raid_attr_show_internal(attr, fmt, var, code) \ +static ssize_t raid_show_##attr(struct class_device *cdev, char *buf) \ +{ \ + struct raid_data *rd = class_get_devdata(cdev); \ + code \ + return snprintf(buf, 20, #fmt "\n", var); \ +} + +#define raid_attr_ro_states(attr, states, code) \ +raid_attr_show_internal(attr, %s, name, \ + const char *name; \ + code \ + name = raid_##states##_name(rd->attr); \ +) \ +static CLASS_DEVICE_ATTR(attr, S_IRUGO, raid_show_##attr, NULL) + + +#define raid_attr_ro_internal(attr, code) \ +raid_attr_show_internal(attr, %d, rd->attr, code) \ +static CLASS_DEVICE_ATTR(attr, S_IRUGO, raid_show_##attr, NULL) + +#define ATTR_CODE(attr) \ + struct raid_internal *i = class_device_to_raid_internal(cdev); \ + if (i->f->get_##attr) \ + i->f->get_##attr(cdev->dev); + +#define raid_attr_ro(attr) raid_attr_ro_internal(attr, ) +#define raid_attr_ro_fn(attr) raid_attr_ro_internal(attr, ATTR_CODE(attr)) +#define raid_attr_ro_state(attr) raid_attr_ro_states(attr, attr, ATTR_CODE(attr)) + +raid_attr_ro(level); +raid_attr_ro_fn(resync); +raid_attr_ro_state(state); + +void raid_component_add(struct raid_template *r,struct device *raid_dev, + struct device *component_dev) +{ + struct class_device *cdev = + attribute_container_find_class_device(&r->raid_attrs.ac, + raid_dev); + struct raid_component *rc; + struct raid_data *rd = class_get_devdata(cdev); + char buf[40]; + + rc = kmalloc(sizeof(*rc), GFP_KERNEL); + if (!rc) + return; + + INIT_LIST_HEAD(&rc->node); + rc->dev = component_dev; + rc->num = rd->component_count++; + + snprintf(buf, sizeof(buf), "component-%d", rc->num); + list_add_tail(&rc->node, &rd->component_list); + sysfs_create_link(&cdev->kobj, &component_dev->kobj, buf); +} +EXPORT_SYMBOL(raid_component_add); + +struct raid_template * +raid_class_attach(struct raid_function_template *ft) +{ + struct raid_internal *i = kmalloc(sizeof(struct raid_internal), + GFP_KERNEL); + int count = 0; + + if (unlikely(!i)) + return NULL; + + memset(i, 0, sizeof(*i)); + + i->f = ft; + + i->r.raid_attrs.ac.class = &raid_class.class; + i->r.raid_attrs.ac.match = raid_match; + i->r.raid_attrs.ac.attrs = &i->attrs[0]; + + attribute_container_register(&i->r.raid_attrs.ac); + + i->attrs[count++] = &class_device_attr_level; + i->attrs[count++] = &class_device_attr_resync; + i->attrs[count++] = &class_device_attr_state; + + i->attrs[count] = NULL; + BUG_ON(count > RAID_NUM_ATTRS); + + return &i->r; +} +EXPORT_SYMBOL(raid_class_attach); + +void +raid_class_release(struct raid_template *r) +{ + struct raid_internal *i = to_raid_internal(r); + + attribute_container_unregister(&i->r.raid_attrs.ac); + + kfree(i); +} +EXPORT_SYMBOL(raid_class_release); + +static __init int raid_init(void) +{ + return transport_class_register(&raid_class); +} + +static __exit void raid_exit(void) +{ + transport_class_unregister(&raid_class); +} + +MODULE_AUTHOR("James Bottomley"); +MODULE_DESCRIPTION("RAID device class"); +MODULE_LICENSE("GPL"); + +module_init(raid_init); +module_exit(raid_exit); + |