LXR linux/drivers/staging/hv/storvsc

   1/*
   2 *
   3 * Copyright (c) 2009, Microsoft Corporation.
   4 *
   5 * This program is free software; you can redistribute it and/or modify it
   6 * under the terms and conditions of the GNU General Public License,
   7 * version 2, as published by the Free Software Foundation.
   8 *
   9 * This program is distributed in the hope it will be useful, but WITHOUT
  10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  12 * more details.
  13 *
  14 * You should have received a copy of the GNU General Public License along with
  15 * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
  16 * Place - Suite 330, Boston, MA 02111-1307 USA.
  17 *
  18 * Authors:
  19 *   Haiyang Zhang <haiyangz@microsoft.com>
  20 *   Hank Janssen  <hjanssen@microsoft.com>
  21 *
  22 */
  23
  24
  25#ifndef _STORVSC_API_H_
  26#define _STORVSC_API_H_
  27
  28#include "vmbus_api.h"
  29
  30/* Defines */
  31#define STORVSC_RING_BUFFER_SIZE                        (20*PAGE_SIZE)
  32#define BLKVSC_RING_BUFFER_SIZE                         (20*PAGE_SIZE)
  33
  34#define STORVSC_MAX_IO_REQUESTS                         128
  35
  36/*
  37 * In Hyper-V, each port/path/target maps to 1 scsi host adapter.  In
  38 * reality, the path/target is not used (ie always set to 0) so our
  39 * scsi host adapter essentially has 1 bus with 1 target that contains
  40 * up to 256 luns.
  41 */
  42#define STORVSC_MAX_LUNS_PER_TARGET                     64
  43#define STORVSC_MAX_TARGETS                             1
  44#define STORVSC_MAX_CHANNELS                            1
  45
  46struct hv_storvsc_request;
  47
  48/* Matches Windows-end */
  49enum storvsc_request_type{
  50        WRITE_TYPE,
  51        READ_TYPE,
  52        UNKNOWN_TYPE,
  53};
  54
  55struct hv_storvsc_request {
  56        enum storvsc_request_type type;
  57        u32 host;
  58        u32 bus;
  59        u32 target_id;
  60        u32 lun_id;
  61        u8 *cdb;
  62        u32 cdb_len;
  63        u32 status;
  64        u32 bytes_xfer;
  65
  66        unsigned char *sense_buffer;
  67        u32 sense_buffer_size;
  68
  69        void *context;
  70
  71        void (*on_io_completion)(struct hv_storvsc_request *request);
  72
  73        /* This points to the memory after DataBuffer */
  74        void *extension;
  75
  76        struct hv_multipage_buffer data_buffer;
  77};
  78
  79/* Represents the block vsc driver */
  80struct storvsc_driver_object {
  81        /* Must be the first field */
  82        /* Which is a bug FIXME! */
  83        struct hv_driver base;
  84
  85        /* Set by caller (in bytes) */
  86        u32 ring_buffer_size;
  87
  88        /* Allocate this much private extension for each I/O request */
  89        u32 request_ext_size;
  90
  91        /* Maximum # of requests in flight per channel/device */
  92        u32 max_outstanding_req_per_channel;
  93
  94        /* Specific to this driver */
  95        int (*on_io_request)(struct hv_device *device,
  96                           struct hv_storvsc_request *request);
  97};
  98
  99struct storvsc_device_info {
 100        unsigned int port_number;
 101        unsigned char path_id;
 102        unsigned char target_id;
 103};
 104
 105/* Interface */
 106int stor_vsc_initialize(struct hv_driver *driver);
 107int stor_vsc_on_host_reset(struct hv_device *device);
 108int blk_vsc_initialize(struct hv_driver *driver);
 109
 110#endif /* _STORVSC_API_H_ */
 111