Bootloaders/MassStorage/Lib/SCSI.c

   1 /*
   2              LUFA Library
   3      Copyright (C) Dean Camera, 2013.
   4
   5   dean [at] fourwalledcubicle [dot] com
   6            www.lufa-lib.org
   7 */
   8
   9 /*
  10   Copyright 2013  Dean Camera (dean [at] fourwalledcubicle [dot] com)
  11
  12   Permission to use, copy, modify, distribute, and sell this
  13   software and its documentation for any purpose is hereby granted
  14   without fee, provided that the above copyright notice appear in
  15   all copies and that both that the copyright notice and this
  16   permission notice and warranty disclaimer appear in supporting
  17   documentation, and that the name of the author not be used in
  18   advertising or publicity pertaining to distribution of the
  19   software without specific, written prior permission.
  20
  21   The author disclaims all warranties with regard to this
  22   software, including all implied warranties of merchantability
  23   and fitness.  In no event shall the author be liable for any
  24   special, indirect or consequential damages or any damages
  25   whatsoever resulting from loss of use, data or profits, whether
  26   in an action of contract, negligence or other tortious action,
  27   arising out of or in connection with the use or performance of
  28   this software.
  29 */
  30
  31 /** \file
  32  *
  33  *  SCSI command processing routines, for SCSI commands issued by the host. Mass Storage
  34  *  devices use a thin "Bulk-Only Transport" protocol for issuing commands and status information,
  35  *  which wrap around standard SCSI device commands for controlling the actual storage medium.
  36  */
  37
  38 #define  INCLUDE_FROM_SCSI_C
  39 #include "SCSI.h"
  40
  41 /** Structure to hold the SCSI response data to a SCSI INQUIRY command. This gives information about the device's
  42  *  features and capabilities.
  43  */
  44 static const SCSI_Inquiry_Response_t InquiryData =
  45         {
  46                 .DeviceType          = DEVICE_TYPE_BLOCK,
  47                 .PeripheralQualifier = 0,
  48
  49                 .Removable           = true,
  50
  51                 .Version             = 0,
  52
  53                 .ResponseDataFormat  = 2,
  54                 .NormACA             = false,
  55                 .TrmTsk              = false,
  56                 .AERC                = false,
  57
  58                 .AdditionalLength    = 0x1F,
  59
  60                 .SoftReset           = false,
  61                 .CmdQue              = false,
  62                 .Linked              = false,
  63                 .Sync                = false,
  64                 .WideBus16Bit        = false,
  65                 .WideBus32Bit        = false,
  66                 .RelAddr             = false,
  67
  68                 .VendorID            = "LUFA",
  69                 .ProductID           = "Bootloader",
  70                 .RevisionID          = {'0','.','0','0'},
  71         };
  72
  73 /** Structure to hold the sense data for the last issued SCSI command, which is returned to the host after a SCSI REQUEST SENSE
  74  *  command is issued. This gives information on exactly why the last command failed to complete.
  75  */
  76 static SCSI_Request_Sense_Response_t SenseData =
  77         {
  78                 .ResponseCode        = 0x70,
  79                 .AdditionalLength    = 0x0A,
  80         };
  81
  82
  83 /** Main routine to process the SCSI command located in the Command Block Wrapper read from the host. This dispatches
  84  *  to the appropriate SCSI command handling routine if the issued command is supported by the device, else it returns
  85  *  a command failure due to a ILLEGAL REQUEST.
  86  *
  87  *  \param[in] MSInterfaceInfo  Pointer to the Mass Storage class interface structure that the command is associated with
  88  *
  89  *  \return Boolean \c true if the command completed successfully, \c false otherwise
  90  */
  91 bool SCSI_DecodeSCSICommand(USB_ClassInfo_MS_Device_t* const MSInterfaceInfo)
  92 {
  93         bool CommandSuccess = false;
  94
  95         /* Run the appropriate SCSI command hander function based on the passed command */
  96         switch (MSInterfaceInfo->State.CommandBlock.SCSICommandData[0])
  97         {
  98                 case SCSI_CMD_INQUIRY:
  99                         CommandSuccess = SCSI_Command_Inquiry(MSInterfaceInfo);
 100                         break;
 101                 case SCSI_CMD_REQUEST_SENSE:
 102                         CommandSuccess = SCSI_Command_Request_Sense(MSInterfaceInfo);
 103                         break;
 104                 case SCSI_CMD_READ_CAPACITY_10:
 105                         CommandSuccess = SCSI_Command_Read_Capacity_10(MSInterfaceInfo);
 106                         break;
 107                 case SCSI_CMD_WRITE_10:
 108                         CommandSuccess = SCSI_Command_ReadWrite_10(MSInterfaceInfo, DATA_WRITE);
 109                         break;
 110                 case SCSI_CMD_READ_10:
 111                         CommandSuccess = SCSI_Command_ReadWrite_10(MSInterfaceInfo, DATA_READ);
 112                         break;
 113                 case SCSI_CMD_MODE_SENSE_6:
 114                         CommandSuccess = SCSI_Command_ModeSense_6(MSInterfaceInfo);
 115                         break;
 116                 case SCSI_CMD_SEND_DIAGNOSTIC:
 117                 case SCSI_CMD_START_STOP_UNIT:
 118                 case SCSI_CMD_TEST_UNIT_READY:
 119                 case SCSI_CMD_PREVENT_ALLOW_MEDIUM_REMOVAL:
 120                 case SCSI_CMD_VERIFY_10:
 121                         /* These commands should just succeed, no handling required */
 122                         CommandSuccess = true;
 123                         MSInterfaceInfo->State.CommandBlock.DataTransferLength = 0;
 124                         break;
 125                 default:
 126                         /* Update the SENSE key to reflect the invalid command */
 127                         SCSI_SET_SENSE(SCSI_SENSE_KEY_ILLEGAL_REQUEST,
 128                                    SCSI_ASENSE_INVALID_COMMAND,
 129                                    SCSI_ASENSEQ_NO_QUALIFIER);
 130                         break;
 131         }
 132
 133         /* Check if command was successfully processed */
 134         if (CommandSuccess)
 135         {
 136                 SCSI_SET_SENSE(SCSI_SENSE_KEY_GOOD,
 137                                SCSI_ASENSE_NO_ADDITIONAL_INFORMATION,
 138                                SCSI_ASENSEQ_NO_QUALIFIER);
 139
 140                 return true;
 141         }
 142
 143         return false;
 144 }
 145
 146 /** Command processing for an issued SCSI INQUIRY command. This command returns information about the device's features
 147  *  and capabilities to the host.
 148  *
 149  *  \param[in] MSInterfaceInfo  Pointer to the Mass Storage class interface structure that the command is associated with
 150  *
 151  *  \return Boolean \c true if the command completed successfully, \c false otherwise.
 152  */
 153 static bool SCSI_Command_Inquiry(USB_ClassInfo_MS_Device_t* const MSInterfaceInfo)
 154 {
 155         uint16_t AllocationLength  = SwapEndian_16(*(uint16_t*)&MSInterfaceInfo->State.CommandBlock.SCSICommandData[3]);
 156         uint16_t BytesTransferred  = MIN(AllocationLength, sizeof(InquiryData));
 157
 158         /* Only the standard INQUIRY data is supported, check if any optional INQUIRY bits set */
 159         if ((MSInterfaceInfo->State.CommandBlock.SCSICommandData[1] & ((1 << 0) | (1 << 1))) ||
 160              MSInterfaceInfo->State.CommandBlock.SCSICommandData[2])
 161         {
 162                 /* Optional but unsupported bits set - update the SENSE key and fail the request */
 163                 SCSI_SET_SENSE(SCSI_SENSE_KEY_ILLEGAL_REQUEST,
 164                                SCSI_ASENSE_INVALID_FIELD_IN_CDB,
 165                                SCSI_ASENSEQ_NO_QUALIFIER);
 166
 167                 return false;
 168         }
 169
 170         Endpoint_Write_Stream_LE(&InquiryData, BytesTransferred, NULL);
 171
 172         /* Pad out remaining bytes with 0x00 */
 173         Endpoint_Null_Stream((AllocationLength - BytesTransferred), NULL);
 174
 175         /* Finalize the stream transfer to send the last packet */
 176         Endpoint_ClearIN();
 177
 178         /* Succeed the command and update the bytes transferred counter */
 179         MSInterfaceInfo->State.CommandBlock.DataTransferLength -= BytesTransferred;
 180
 181         return true;
 182 }
 183
 184 /** Command processing for an issued SCSI REQUEST SENSE command. This command returns information about the last issued command,
 185  *  including the error code and additional error information so that the host can determine why a command failed to complete.
 186  *
 187  *  \param[in] MSInterfaceInfo  Pointer to the Mass Storage class interface structure that the command is associated with
 188  *
 189  *  \return Boolean \c true if the command completed successfully, \c false otherwise.
 190  */
 191 static bool SCSI_Command_Request_Sense(USB_ClassInfo_MS_Device_t* const MSInterfaceInfo)
 192 {
 193         uint8_t AllocationLength = MSInterfaceInfo->State.CommandBlock.SCSICommandData[4];
 194         uint8_t BytesTransferred = MIN(AllocationLength, sizeof(SenseData));
 195
 196         Endpoint_Write_Stream_LE(&SenseData, BytesTransferred, NULL);
 197         Endpoint_Null_Stream((AllocationLength - BytesTransferred), NULL);
 198         Endpoint_ClearIN();
 199
 200         /* Succeed the command and update the bytes transferred counter */
 201         MSInterfaceInfo->State.CommandBlock.DataTransferLength -= BytesTransferred;
 202
 203         return true;
 204 }
 205
 206 /** Command processing for an issued SCSI READ CAPACITY (10) command. This command returns information about the device's capacity
 207  *  on the selected Logical Unit (drive), as a number of OS-sized blocks.
 208  *
 209  *  \param[in] MSInterfaceInfo  Pointer to the Mass Storage class interface structure that the command is associated with
 210  *
 211  *  \return Boolean \c true if the command completed successfully, \c false otherwise.
 212  */
 213 static bool SCSI_Command_Read_Capacity_10(USB_ClassInfo_MS_Device_t* const MSInterfaceInfo)
 214 {
 215         uint32_t LastBlockAddressInLUN = (LUN_MEDIA_BLOCKS - 1);
 216         uint32_t MediaBlockSize        = SECTOR_SIZE_BYTES;
 217
 218         Endpoint_Write_Stream_BE(&LastBlockAddressInLUN, sizeof(LastBlockAddressInLUN), NULL);
 219         Endpoint_Write_Stream_BE(&MediaBlockSize, sizeof(MediaBlockSize), NULL);
 220         Endpoint_ClearIN();
 221
 222         /* Succeed the command and update the bytes transferred counter */
 223         MSInterfaceInfo->State.CommandBlock.DataTransferLength -= 8;
 224
 225         return true;
 226 }
 227
 228 /** Command processing for an issued SCSI READ (10) or WRITE (10) command. This command reads in the block start address
 229  *  and total number of blocks to process, then calls the appropriate low-level Dataflash routine to handle the actual
 230  *  reading and writing of the data.
 231  *
 232  *  \param[in] MSInterfaceInfo  Pointer to the Mass Storage class interface structure that the command is associated with
 233  *  \param[in] IsDataRead  Indicates if the command is a READ (10) command or WRITE (10) command (DATA_READ or DATA_WRITE)
 234  *
 235  *  \return Boolean \c true if the command completed successfully, \c false otherwise.
 236  */
 237 static bool SCSI_Command_ReadWrite_10(USB_ClassInfo_MS_Device_t* const MSInterfaceInfo,
 238                                       const bool IsDataRead)
 239 {
 240         uint32_t BlockAddress;
 241         uint16_t TotalBlocks;
 242
 243         /* Load in the 32-bit block address (SCSI uses big-endian, so have to reverse the byte order) */
 244         BlockAddress = SwapEndian_32(*(uint32_t*)&MSInterfaceInfo->State.CommandBlock.SCSICommandData[2]);
 245
 246         /* Load in the 16-bit total blocks (SCSI uses big-endian, so have to reverse the byte order) */
 247         TotalBlocks  = SwapEndian_16(*(uint16_t*)&MSInterfaceInfo->State.CommandBlock.SCSICommandData[7]);
 248
 249         /* Check if the block address is outside the maximum allowable value for the LUN */
 250         if (BlockAddress >= LUN_MEDIA_BLOCKS)
 251         {
 252                 /* Block address is invalid, update SENSE key and return command fail */
 253                 SCSI_SET_SENSE(SCSI_SENSE_KEY_ILLEGAL_REQUEST,
 254                                SCSI_ASENSE_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE,
 255                                SCSI_ASENSEQ_NO_QUALIFIER);
 256
 257                 return false;
 258         }
 259
 260         /* Determine if the packet is a READ (10) or WRITE (10) command, call appropriate function */
 261         if (IsDataRead == DATA_READ)
 262           VirtualFAT_ReadBlocks(MSInterfaceInfo, BlockAddress, TotalBlocks);
 263         else
 264           VirtualFAT_WriteBlocks(MSInterfaceInfo, BlockAddress, TotalBlocks);
 265
 266         /* Update the bytes transferred counter and succeed the command */
 267         MSInterfaceInfo->State.CommandBlock.DataTransferLength -= ((uint32_t)TotalBlocks * SECTOR_SIZE_BYTES);
 268
 269         return true;
 270 }
 271
 272 /** Command processing for an issued SCSI MODE SENSE (6) command. This command returns various informational pages about
 273  *  the SCSI device, as well as the device's Write Protect status.
 274  *
 275  *  \param[in] MSInterfaceInfo  Pointer to the Mass Storage class interface structure that the command is associated with
 276  *
 277  *  \return Boolean \c true if the command completed successfully, \c false otherwise.
 278  */
 279 static bool SCSI_Command_ModeSense_6(USB_ClassInfo_MS_Device_t* const MSInterfaceInfo)
 280 {
 281         /* Send an empty header response indicating Write Protect flag is off */
 282         Endpoint_Write_32_LE(0);
 283         Endpoint_ClearIN();
 284
 285         /* Update the bytes transferred counter and succeed the command */
 286         MSInterfaceInfo->State.CommandBlock.DataTransferLength -= 4;
 287
 288         return true;
 289 }
 290