diff options
Diffstat (limited to 'drivers/staging/hv/hyperv_storage.h')
-rw-r--r-- | drivers/staging/hv/hyperv_storage.h | 134 |
1 files changed, 134 insertions, 0 deletions
diff --git a/drivers/staging/hv/hyperv_storage.h b/drivers/staging/hv/hyperv_storage.h index 4fafc71f7e0c..a01f9a07c988 100644 --- a/drivers/staging/hv/hyperv_storage.h +++ b/drivers/staging/hv/hyperv_storage.h @@ -197,4 +197,138 @@ struct vstor_packet { /* This is the set of flags that the vsc can set in any packets it sends */ #define VSC_LEGAL_FLAGS (REQUEST_COMPLETION_FLAG) + +#include <linux/kernel.h> +#include <linux/wait.h> +#include "hyperv_storage.h" +#include "hyperv.h" + +/* Defines */ +#define STORVSC_RING_BUFFER_SIZE (20*PAGE_SIZE) +#define BLKVSC_RING_BUFFER_SIZE (20*PAGE_SIZE) + +#define STORVSC_MAX_IO_REQUESTS 128 + +/* + * In Hyper-V, each port/path/target maps to 1 scsi host adapter. In + * reality, the path/target is not used (ie always set to 0) so our + * scsi host adapter essentially has 1 bus with 1 target that contains + * up to 256 luns. + */ +#define STORVSC_MAX_LUNS_PER_TARGET 64 +#define STORVSC_MAX_TARGETS 1 +#define STORVSC_MAX_CHANNELS 1 + +struct hv_storvsc_request; + +/* Matches Windows-end */ +enum storvsc_request_type { + WRITE_TYPE, + READ_TYPE, + UNKNOWN_TYPE, +}; + + +struct hv_storvsc_request { + struct hv_storvsc_request *request; + struct hv_device *device; + + /* Synchronize the request/response if needed */ + struct completion wait_event; + + unsigned char *sense_buffer; + void *context; + void (*on_io_completion)(struct hv_storvsc_request *request); + struct hv_multipage_buffer data_buffer; + + struct vstor_packet vstor_packet; +}; + + +struct storvsc_device_info { + u32 ring_buffer_size; + unsigned int port_number; + unsigned char path_id; + unsigned char target_id; +}; + +struct storvsc_major_info { + int major; + int index; + bool do_register; + char *devname; + char *diskname; +}; + +/* A storvsc device is a device object that contains a vmbus channel */ +struct storvsc_device { + struct hv_device *device; + + /* 0 indicates the device is being destroyed */ + atomic_t ref_count; + + bool drain_notify; + atomic_t num_outstanding_req; + + wait_queue_head_t waiting_to_drain; + + /* + * Each unique Port/Path/Target represents 1 channel ie scsi + * controller. In reality, the pathid, targetid is always 0 + * and the port is set by us + */ + unsigned int port_number; + unsigned char path_id; + unsigned char target_id; + + /* Used for vsc/vsp channel reset process */ + struct hv_storvsc_request init_request; + struct hv_storvsc_request reset_request; +}; + + +/* Get the stordevice object iff exists and its refcount > 1 */ +static inline struct storvsc_device *get_stor_device(struct hv_device *device) +{ + struct storvsc_device *stor_device; + + stor_device = (struct storvsc_device *)device->ext; + if (stor_device && atomic_read(&stor_device->ref_count) > 1) + atomic_inc(&stor_device->ref_count); + else + stor_device = NULL; + + return stor_device; +} + + +static inline void put_stor_device(struct hv_device *device) +{ + struct storvsc_device *stor_device; + + stor_device = (struct storvsc_device *)device->ext; + + atomic_dec(&stor_device->ref_count); +} + +static inline void storvsc_wait_to_drain(struct storvsc_device *dev) +{ + dev->drain_notify = true; + wait_event(dev->waiting_to_drain, + atomic_read(&dev->num_outstanding_req) == 0); + dev->drain_notify = false; +} + +/* Interface */ + +int storvsc_dev_add(struct hv_device *device, + void *additional_info); +int storvsc_dev_remove(struct hv_device *device); + +int storvsc_do_io(struct hv_device *device, + struct hv_storvsc_request *request); + +int storvsc_get_major_info(struct storvsc_device_info *device_info, + struct storvsc_major_info *major_info); + #endif /* _HYPERV_STORAGE_H */ |