drivers/staging/hv/storvsc_api.h

   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
  46 struct hv_storvsc_request;
  47
  48 /* Matches Windows-end */
  49 enum storvsc_request_type{
  50         WRITE_TYPE,
  51         READ_TYPE,
  52         UNKNOWN_TYPE,
  53 };
  54
  55 struct 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 */
  80 struct 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
  99 struct storvsc_device_info {
 100         unsigned int port_number;
 101         unsigned char path_id;
 102         unsigned char target_id;
 103 };
 104
 105 /* Interface */
 106 int stor_vsc_initialize(struct hv_driver *driver);
 107 int stor_vsc_on_host_reset(struct hv_device *device);
 108 int blk_vsc_initialize(struct hv_driver *driver);
 109
 110 #endif /* _STORVSC_API_H_ */