Pileus Git - ~andy/linux/blob - drivers/staging/hv/BlkVsc.c

   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  *   Hank Janssen  <hjanssen@microsoft.com>
  20  *
  21  */
  22
  23 #include <linux/kernel.h>
  24 #include "StorVsc.c"
  25
  26 static const char* gBlkDriverName="blkvsc";
  27
  28 //{32412632-86cb-44a2-9b5c-50d1417354f5}
  29 static const GUID gBlkVscDeviceType={
  30         .Data = {0x32, 0x26, 0x41, 0x32, 0xcb, 0x86, 0xa2, 0x44, 0x9b, 0x5c, 0x50, 0xd1, 0x41, 0x73, 0x54, 0xf5}
  31 };
  32
  33 // Static routines
  34 static int
  35 BlkVscOnDeviceAdd(
  36         DEVICE_OBJECT   *Device,
  37         void                    *AdditionalInfo
  38         );
  39
  40
  41 int
  42 BlkVscInitialize(
  43         DRIVER_OBJECT *Driver
  44         )
  45 {
  46         STORVSC_DRIVER_OBJECT* storDriver = (STORVSC_DRIVER_OBJECT*)Driver;
  47         int ret=0;
  48
  49         DPRINT_ENTER(BLKVSC);
  50
  51         // Make sure we are at least 2 pages since 1 page is used for control
  52         ASSERT(storDriver->RingBufferSize >= (PAGE_SIZE << 1));
  53
  54         Driver->name = gBlkDriverName;
  55         memcpy(&Driver->deviceType, &gBlkVscDeviceType, sizeof(GUID));
  56
  57         storDriver->RequestExtSize                      = sizeof(STORVSC_REQUEST_EXTENSION);
  58         // Divide the ring buffer data size (which is 1 page less than the ring buffer size since that page is reserved for the ring buffer indices)
  59         // by the max request size (which is VMBUS_CHANNEL_PACKET_MULITPAGE_BUFFER + VSTOR_PACKET + UINT64)
  60         storDriver->MaxOutstandingRequestsPerChannel =
  61                 ((storDriver->RingBufferSize - PAGE_SIZE) / ALIGN_UP(MAX_MULTIPAGE_BUFFER_PACKET + sizeof(VSTOR_PACKET) + sizeof(UINT64),sizeof(UINT64)));
  62
  63         DPRINT_INFO(BLKVSC, "max io outstd %u", storDriver->MaxOutstandingRequestsPerChannel);
  64
  65         // Setup the dispatch table
  66         storDriver->Base.OnDeviceAdd            = BlkVscOnDeviceAdd;
  67         storDriver->Base.OnDeviceRemove         = StorVscOnDeviceRemove;
  68         storDriver->Base.OnCleanup                      = StorVscOnCleanup;
  69
  70         storDriver->OnIORequest                         = StorVscOnIORequest;
  71
  72         DPRINT_EXIT(BLKVSC);
  73
  74         return ret;
  75 }
  76
  77 int
  78 BlkVscOnDeviceAdd(
  79         DEVICE_OBJECT   *Device,
  80         void                    *AdditionalInfo
  81         )
  82 {
  83         int ret=0;
  84         STORVSC_DEVICE_INFO *deviceInfo = (STORVSC_DEVICE_INFO*)AdditionalInfo;
  85
  86         DPRINT_ENTER(BLKVSC);
  87
  88         ret = StorVscOnDeviceAdd(Device, AdditionalInfo);
  89
  90         if (ret != 0)
  91         {
  92                 DPRINT_EXIT(BLKVSC);
  93
  94                 return ret;
  95         }
  96
  97         // We need to use the device instance guid to set the path and target id. For IDE devices, the
  98         // device instance id is formatted as <bus id> - <device id> - 8899 - 000000000000.
  99         deviceInfo->PathId = Device->deviceInstance.Data[3] << 24 | Device->deviceInstance.Data[2] << 16 |
 100                 Device->deviceInstance.Data[1] << 8 |Device->deviceInstance.Data[0];
 101
 102         deviceInfo->TargetId = Device->deviceInstance.Data[5] << 8 | Device->deviceInstance.Data[4];
 103
 104         DPRINT_EXIT(BLKVSC);
 105
 106         return ret;
 107 }