Projects/Webserver/Lib/SCSI.c

   1 /*
   2              LUFA Library
   3      Copyright (C) Dean Camera, 2010.
   4
   5   dean [at] fourwalledcubicle [dot] com
   6       www.fourwalledcubicle.com
   7 */
   8
   9 /*
  10   Copyright 2010  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 disclaim 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 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           = "Dataflash Disk",
  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 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 true if the command completed successfully, 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_SEND_DIAGNOSTIC:
 108                         CommandSuccess = SCSI_Command_Send_Diagnostic(MSInterfaceInfo);
 109                         break;
 110                 case SCSI_CMD_WRITE_10:
 111                         CommandSuccess = SCSI_Command_ReadWrite_10(MSInterfaceInfo, DATA_WRITE);
 112                         break;
 113                 case SCSI_CMD_READ_10:
 114                         CommandSuccess = SCSI_Command_ReadWrite_10(MSInterfaceInfo, DATA_READ);
 115                         break;
 116                 case SCSI_CMD_TEST_UNIT_READY:
 117                 case SCSI_CMD_PREVENT_ALLOW_MEDIUM_REMOVAL:
 118                 case SCSI_CMD_VERIFY_10:
 119                         /* These commands should just succeed, no handling required */
 120                         CommandSuccess = true;
 121                         MSInterfaceInfo->State.CommandBlock.DataTransferLength = 0;
 122                         break;
 123                 default:
 124                         /* Update the SENSE key to reflect the invalid command */
 125                         SCSI_SET_SENSE(SCSI_SENSE_KEY_ILLEGAL_REQUEST,
 126                                    SCSI_ASENSE_INVALID_COMMAND,
 127                                    SCSI_ASENSEQ_NO_QUALIFIER);
 128                         break;
 129         }
 130
 131         /* Check if command was successfully processed */
 132         if (CommandSuccess)
 133         {
 134                 SCSI_SET_SENSE(SCSI_SENSE_KEY_GOOD,
 135                                SCSI_ASENSE_NO_ADDITIONAL_INFORMATION,
 136                                SCSI_ASENSEQ_NO_QUALIFIER);
 137
 138                 return true;
 139         }
 140
 141         return false;
 142 }
 143
 144 /** Command processing for an issued SCSI INQUIRY command. This command returns information about the device's features
 145  *  and capabilities to the host.
 146  *
 147  *  \param[in] MSInterfaceInfo  Pointer to the Mass Storage class interface structure that the command is associated with
 148  *
 149  *  \return Boolean true if the command completed successfully, false otherwise.
 150  */
 151 static bool SCSI_Command_Inquiry(USB_ClassInfo_MS_Device_t* const MSInterfaceInfo)
 152 {
 153         uint16_t AllocationLength  = SwapEndian_16(*(uint16_t*)&MSInterfaceInfo->State.CommandBlock.SCSICommandData[3]);
 154         uint16_t BytesTransferred  = (AllocationLength < sizeof(InquiryData))? AllocationLength :
 155                                                                                sizeof(InquiryData);
 156
 157         /* Only the standard INQUIRY data is supported, check if any optional INQUIRY bits set */
 158         if ((MSInterfaceInfo->State.CommandBlock.SCSICommandData[1] & ((1 << 0) | (1 << 1))) ||
 159              MSInterfaceInfo->State.CommandBlock.SCSICommandData[2])
 160         {
 161                 /* Optional but unsupported bits set - update the SENSE key and fail the request */
 162                 SCSI_SET_SENSE(SCSI_SENSE_KEY_ILLEGAL_REQUEST,
 163                                SCSI_ASENSE_INVALID_FIELD_IN_CDB,
 164                                SCSI_ASENSEQ_NO_QUALIFIER);
 165
 166                 return false;
 167         }
 168
 169         Endpoint_Write_Stream_LE(&InquiryData, BytesTransferred, NO_STREAM_CALLBACK);
 170
 171         uint8_t PadBytes[AllocationLength - BytesTransferred];
 172
 173         /* Pad out remaining bytes with 0x00 */
 174         Endpoint_Write_Stream_LE(&PadBytes, sizeof(PadBytes), NO_STREAM_CALLBACK);
 175
 176         /* Finalize the stream transfer to send the last packet */
 177         Endpoint_ClearIN();
 178
 179         /* Succeed the command and update the bytes transferred counter */
 180         MSInterfaceInfo->State.CommandBlock.DataTransferLength -= BytesTransferred;
 181
 182         return true;
 183 }
 184
 185 /** Command processing for an issued SCSI REQUEST SENSE command. This command returns information about the last issued command,
 186  *  including the error code and additional error information so that the host can determine why a command failed to complete.
 187  *
 188  *  \param[in] MSInterfaceInfo  Pointer to the Mass Storage class interface structure that the command is associated with
 189  *
 190  *  \return Boolean true if the command completed successfully, false otherwise.
 191  */
 192 static bool SCSI_Command_Request_Sense(USB_ClassInfo_MS_Device_t* const MSInterfaceInfo)
 193 {
 194         uint8_t  AllocationLength = MSInterfaceInfo->State.CommandBlock.SCSICommandData[4];
 195         uint8_t  BytesTransferred = (AllocationLength < sizeof(SenseData))? AllocationLength : sizeof(SenseData);
 196
 197         uint8_t PadBytes[AllocationLength - BytesTransferred];
 198
 199         Endpoint_Write_Stream_LE(&SenseData, BytesTransferred, NO_STREAM_CALLBACK);
 200         Endpoint_Write_Stream_LE(&PadBytes, sizeof(PadBytes), NO_STREAM_CALLBACK);
 201         Endpoint_ClearIN();
 202
 203         /* Succeed the command and update the bytes transferred counter */
 204         MSInterfaceInfo->State.CommandBlock.DataTransferLength -= BytesTransferred;
 205
 206         return true;
 207 }
 208
 209 /** Command processing for an issued SCSI READ CAPACITY (10) command. This command returns information about the device's capacity
 210  *  on the selected Logical Unit (drive), as a number of OS-sized blocks.
 211  *
 212  *  \param[in] MSInterfaceInfo  Pointer to the Mass Storage class interface structure that the command is associated with
 213  *
 214  *  \return Boolean true if the command completed successfully, false otherwise.
 215  */
 216 static bool SCSI_Command_Read_Capacity_10(USB_ClassInfo_MS_Device_t* const MSInterfaceInfo)
 217 {
 218         uint32_t LastBlockAddressInLUN = (VIRTUAL_MEMORY_BLOCKS - 1);
 219         uint32_t MediaBlockSize        = VIRTUAL_MEMORY_BLOCK_SIZE;
 220
 221         Endpoint_Write_Stream_BE(&LastBlockAddressInLUN, sizeof(LastBlockAddressInLUN), NO_STREAM_CALLBACK);
 222         Endpoint_Write_Stream_BE(&MediaBlockSize, sizeof(MediaBlockSize), NO_STREAM_CALLBACK);
 223         Endpoint_ClearIN();
 224
 225         /* Succeed the command and update the bytes transferred counter */
 226         MSInterfaceInfo->State.CommandBlock.DataTransferLength -= 8;
 227
 228         return true;
 229 }
 230
 231 /** Command processing for an issued SCSI SEND DIAGNOSTIC command. This command performs a quick check of the Dataflash ICs on the
 232  *  board, and indicates if they are present and functioning correctly. Only the Self-Test portion of the diagnostic command is
 233  *  supported.
 234  *
 235  *  \param[in] MSInterfaceInfo  Pointer to the Mass Storage class interface structure that the command is associated with
 236  *
 237  *  \return Boolean true if the command completed successfully, false otherwise.
 238  */
 239 static bool SCSI_Command_Send_Diagnostic(USB_ClassInfo_MS_Device_t* const MSInterfaceInfo)
 240 {
 241         /* Check to see if the SELF TEST bit is not set */
 242         if (!(MSInterfaceInfo->State.CommandBlock.SCSICommandData[1] & (1 << 2)))
 243         {
 244                 /* Only self-test supported - update SENSE key and fail the command */
 245                 SCSI_SET_SENSE(SCSI_SENSE_KEY_ILLEGAL_REQUEST,
 246                                SCSI_ASENSE_INVALID_FIELD_IN_CDB,
 247                                SCSI_ASENSEQ_NO_QUALIFIER);
 248
 249                 return false;
 250         }
 251
 252         /* Check to see if all attached Dataflash ICs are functional */
 253         if (!(DataflashManager_CheckDataflashOperation()))
 254         {
 255                 /* Update SENSE key with a hardware error condition and return command fail */
 256                 SCSI_SET_SENSE(SCSI_SENSE_KEY_HARDWARE_ERROR,
 257                                SCSI_ASENSE_NO_ADDITIONAL_INFORMATION,
 258                                SCSI_ASENSEQ_NO_QUALIFIER);
 259
 260                 return false;
 261         }
 262
 263         /* Succeed the command and update the bytes transferred counter */
 264         MSInterfaceInfo->State.CommandBlock.DataTransferLength = 0;
 265
 266         return true;
 267 }
 268
 269 /** Command processing for an issued SCSI READ (10) or WRITE (10) command. This command reads in the block start address
 270  *  and total number of blocks to process, then calls the appropriate low-level Dataflash routine to handle the actual
 271  *  reading and writing of the data.
 272  *
 273  *  \param[in] MSInterfaceInfo  Pointer to the Mass Storage class interface structure that the command is associated with
 274  *  \param[in] IsDataRead  Indicates if the command is a READ (10) command or WRITE (10) command (DATA_READ or DATA_WRITE)
 275  *
 276  *  \return Boolean true if the command completed successfully, false otherwise.
 277  */
 278 static bool SCSI_Command_ReadWrite_10(USB_ClassInfo_MS_Device_t* const MSInterfaceInfo,
 279                                       const bool IsDataRead)
 280 {
 281         uint32_t BlockAddress;
 282         uint16_t TotalBlocks;
 283
 284         /* Load in the 32-bit block address (SCSI uses big-endian, so have to reverse the byte order) */
 285         BlockAddress = SwapEndian_32(*(uint32_t*)&MSInterfaceInfo->State.CommandBlock.SCSICommandData[2]);
 286
 287         /* Load in the 16-bit total blocks (SCSI uses big-endian, so have to reverse the byte order) */
 288         TotalBlocks  = SwapEndian_16(*(uint16_t*)&MSInterfaceInfo->State.CommandBlock.SCSICommandData[7]);
 289
 290         /* Check if the block address is outside the maximum allowable value for the LUN */
 291         if (BlockAddress >= VIRTUAL_MEMORY_BLOCKS)
 292         {
 293                 /* Block address is invalid, update SENSE key and return command fail */
 294                 SCSI_SET_SENSE(SCSI_SENSE_KEY_ILLEGAL_REQUEST,
 295                                SCSI_ASENSE_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE,
 296                                SCSI_ASENSEQ_NO_QUALIFIER);
 297
 298                 return false;
 299         }
 300
 301         /* Determine if the packet is a READ (10) or WRITE (10) command, call appropriate function */
 302         if (IsDataRead == DATA_READ)
 303           DataflashManager_ReadBlocks(MSInterfaceInfo, BlockAddress, TotalBlocks);
 304         else
 305           DataflashManager_WriteBlocks(MSInterfaceInfo, BlockAddress, TotalBlocks);
 306
 307         /* Update the bytes transferred counter and succeed the command */
 308         MSInterfaceInfo->State.CommandBlock.DataTransferLength -= ((uint32_t)TotalBlocks * VIRTUAL_MEMORY_BLOCK_SIZE);
 309
 310         return true;
 311 }