protocol/lufa/LUFA-git/Projects/Webserver/Lib/SCSI.c

   1 /*
   2              LUFA Library
   3      Copyright (C) Dean Camera, 2014.
   4
   5   dean [at] fourwalledcubicle [dot] com
   6            www.lufa-lib.org
   7 */
   8
   9 /*
  10   Copyright 2014  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           = "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 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_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_MODE_SENSE_6:
 117                         CommandSuccess = SCSI_Command_ModeSense_6(MSInterfaceInfo);
 118                         break;
 119                 case SCSI_CMD_START_STOP_UNIT:
 120                 case SCSI_CMD_TEST_UNIT_READY:
 121                 case SCSI_CMD_PREVENT_ALLOW_MEDIUM_REMOVAL:
 122                 case SCSI_CMD_VERIFY_10:
 123                         /* These commands should just succeed, no handling required */
 124                         CommandSuccess = true;
 125                         MSInterfaceInfo->State.CommandBlock.DataTransferLength = 0;
 126                         break;
 127                 default:
 128                         /* Update the SENSE key to reflect the invalid command */
 129                         SCSI_SET_SENSE(SCSI_SENSE_KEY_ILLEGAL_REQUEST,
 130                                    SCSI_ASENSE_INVALID_COMMAND,
 131                                    SCSI_ASENSEQ_NO_QUALIFIER);
 132                         break;
 133         }
 134
 135         /* Check if command was successfully processed */
 136         if (CommandSuccess)
 137         {
 138                 SCSI_SET_SENSE(SCSI_SENSE_KEY_GOOD,
 139                                SCSI_ASENSE_NO_ADDITIONAL_INFORMATION,
 140                                SCSI_ASENSEQ_NO_QUALIFIER);
 141
 142                 return true;
 143         }
 144
 145         return false;
 146 }
 147
 148 /** Command processing for an issued SCSI INQUIRY command. This command returns information about the device's features
 149  *  and capabilities to the host.
 150  *
 151  *  \param[in] MSInterfaceInfo  Pointer to the Mass Storage class interface structure that the command is associated with
 152  *
 153  *  \return Boolean \c true if the command completed successfully, \c false otherwise.
 154  */
 155 static bool SCSI_Command_Inquiry(USB_ClassInfo_MS_Device_t* const MSInterfaceInfo)
 156 {
 157         uint16_t AllocationLength  = SwapEndian_16(*(uint16_t*)&MSInterfaceInfo->State.CommandBlock.SCSICommandData[3]);
 158         uint16_t BytesTransferred  = MIN(AllocationLength, sizeof(InquiryData));
 159
 160         /* Only the standard INQUIRY data is supported, check if any optional INQUIRY bits set */
 161         if ((MSInterfaceInfo->State.CommandBlock.SCSICommandData[1] & ((1 << 0) | (1 << 1))) ||
 162              MSInterfaceInfo->State.CommandBlock.SCSICommandData[2])
 163         {
 164                 /* Optional but unsupported bits set - update the SENSE key and fail the request */
 165                 SCSI_SET_SENSE(SCSI_SENSE_KEY_ILLEGAL_REQUEST,
 166                                SCSI_ASENSE_INVALID_FIELD_IN_CDB,
 167                                SCSI_ASENSEQ_NO_QUALIFIER);
 168
 169                 return false;
 170         }
 171
 172         Endpoint_Write_Stream_LE(&InquiryData, BytesTransferred, NULL);
 173
 174         /* Pad out remaining bytes with 0x00 */
 175         Endpoint_Null_Stream((AllocationLength - BytesTransferred), NULL);
 176
 177         /* Finalize the stream transfer to send the last packet */
 178         Endpoint_ClearIN();
 179
 180         /* Succeed the command and update the bytes transferred counter */
 181         MSInterfaceInfo->State.CommandBlock.DataTransferLength -= BytesTransferred;
 182
 183         return true;
 184 }
 185
 186 /** Command processing for an issued SCSI REQUEST SENSE command. This command returns information about the last issued command,
 187  *  including the error code and additional error information so that the host can determine why a command failed to complete.
 188  *
 189  *  \param[in] MSInterfaceInfo  Pointer to the Mass Storage class interface structure that the command is associated with
 190  *
 191  *  \return Boolean \c true if the command completed successfully, \c false otherwise.
 192  */
 193 static bool SCSI_Command_Request_Sense(USB_ClassInfo_MS_Device_t* const MSInterfaceInfo)
 194 {
 195         uint8_t  AllocationLength = MSInterfaceInfo->State.CommandBlock.SCSICommandData[4];
 196         uint8_t  BytesTransferred = MIN(AllocationLength, sizeof(SenseData));
 197
 198         Endpoint_Write_Stream_LE(&SenseData, BytesTransferred, NULL);
 199         Endpoint_Null_Stream((AllocationLength - BytesTransferred), NULL);
 200         Endpoint_ClearIN();
 201
 202         /* Succeed the command and update the bytes transferred counter */
 203         MSInterfaceInfo->State.CommandBlock.DataTransferLength -= BytesTransferred;
 204
 205         return true;
 206 }
 207
 208 /** Command processing for an issued SCSI READ CAPACITY (10) command. This command returns information about the device's capacity
 209  *  on the selected Logical Unit (drive), as a number of OS-sized blocks.
 210  *
 211  *  \param[in] MSInterfaceInfo  Pointer to the Mass Storage class interface structure that the command is associated with
 212  *
 213  *  \return Boolean \c true if the command completed successfully, \c false otherwise.
 214  */
 215 static bool SCSI_Command_Read_Capacity_10(USB_ClassInfo_MS_Device_t* const MSInterfaceInfo)
 216 {
 217         uint32_t LastBlockAddressInLUN = (VIRTUAL_MEMORY_BLOCKS - 1);
 218         uint32_t MediaBlockSize        = VIRTUAL_MEMORY_BLOCK_SIZE;
 219
 220         Endpoint_Write_Stream_BE(&LastBlockAddressInLUN, sizeof(LastBlockAddressInLUN), NULL);
 221         Endpoint_Write_Stream_BE(&MediaBlockSize, sizeof(MediaBlockSize), NULL);
 222         Endpoint_ClearIN();
 223
 224         /* Succeed the command and update the bytes transferred counter */
 225         MSInterfaceInfo->State.CommandBlock.DataTransferLength -= 8;
 226
 227         return true;
 228 }
 229
 230 /** Command processing for an issued SCSI SEND DIAGNOSTIC command. This command performs a quick check of the Dataflash ICs on the
 231  *  board, and indicates if they are present and functioning correctly. Only the Self-Test portion of the diagnostic command is
 232  *  supported.
 233  *
 234  *  \param[in] MSInterfaceInfo  Pointer to the Mass Storage class interface structure that the command is associated with
 235  *
 236  *  \return Boolean \c true if the command completed successfully, \c false otherwise.
 237  */
 238 static bool SCSI_Command_Send_Diagnostic(USB_ClassInfo_MS_Device_t* const MSInterfaceInfo)
 239 {
 240         /* Check to see if the SELF TEST bit is not set */
 241         if (!(MSInterfaceInfo->State.CommandBlock.SCSICommandData[1] & (1 << 2)))
 242         {
 243                 /* Only self-test supported - update SENSE key and fail the command */
 244                 SCSI_SET_SENSE(SCSI_SENSE_KEY_ILLEGAL_REQUEST,
 245                                SCSI_ASENSE_INVALID_FIELD_IN_CDB,
 246                                SCSI_ASENSEQ_NO_QUALIFIER);
 247
 248                 return false;
 249         }
 250
 251         /* Check to see if all attached Dataflash ICs are functional */
 252         if (!(DataflashManager_CheckDataflashOperation()))
 253         {
 254                 /* Update SENSE key with a hardware error condition and return command fail */
 255                 SCSI_SET_SENSE(SCSI_SENSE_KEY_HARDWARE_ERROR,
 256                                SCSI_ASENSE_NO_ADDITIONAL_INFORMATION,
 257                                SCSI_ASENSEQ_NO_QUALIFIER);
 258
 259                 return false;
 260         }
 261
 262         /* Succeed the command and update the bytes transferred counter */
 263         MSInterfaceInfo->State.CommandBlock.DataTransferLength = 0;
 264
 265         return true;
 266 }
 267
 268 /** Command processing for an issued SCSI READ (10) or WRITE (10) command. This command reads in the block start address
 269  *  and total number of blocks to process, then calls the appropriate low-level Dataflash routine to handle the actual
 270  *  reading and writing of the data.
 271  *
 272  *  \param[in] MSInterfaceInfo  Pointer to the Mass Storage class interface structure that the command is associated with
 273  *  \param[in] IsDataRead  Indicates if the command is a READ (10) command or WRITE (10) command (DATA_READ or DATA_WRITE)
 274  *
 275  *  \return Boolean \c true if the command completed successfully, \c false otherwise.
 276  */
 277 static bool SCSI_Command_ReadWrite_10(USB_ClassInfo_MS_Device_t* const MSInterfaceInfo,
 278                                       const bool IsDataRead)
 279 {
 280         uint32_t BlockAddress;
 281         uint16_t TotalBlocks;
 282
 283         /* Check if the disk is write protected or not */
 284         if ((IsDataRead == DATA_WRITE) && DISK_READ_ONLY)
 285         {
 286                 /* Block address is invalid, update SENSE key and return command fail */
 287                 SCSI_SET_SENSE(SCSI_SENSE_KEY_DATA_PROTECT,
 288                                SCSI_ASENSE_WRITE_PROTECTED,
 289                                SCSI_ASENSEQ_NO_QUALIFIER);
 290
 291                 return false;
 292         }
 293
 294         /* Load in the 32-bit block address (SCSI uses big-endian, so have to reverse the byte order) */
 295         BlockAddress = SwapEndian_32(*(uint32_t*)&MSInterfaceInfo->State.CommandBlock.SCSICommandData[2]);
 296
 297         /* Load in the 16-bit total blocks (SCSI uses big-endian, so have to reverse the byte order) */
 298         TotalBlocks  = SwapEndian_16(*(uint16_t*)&MSInterfaceInfo->State.CommandBlock.SCSICommandData[7]);
 299
 300         /* Check if the block address is outside the maximum allowable value for the LUN */
 301         if (BlockAddress >= VIRTUAL_MEMORY_BLOCKS)
 302         {
 303                 /* Block address is invalid, update SENSE key and return command fail */
 304                 SCSI_SET_SENSE(SCSI_SENSE_KEY_ILLEGAL_REQUEST,
 305                                SCSI_ASENSE_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE,
 306                                SCSI_ASENSEQ_NO_QUALIFIER);
 307
 308                 return false;
 309         }
 310
 311         /* Determine if the packet is a READ (10) or WRITE (10) command, call appropriate function */
 312         if (IsDataRead == DATA_READ)
 313           DataflashManager_ReadBlocks(MSInterfaceInfo, BlockAddress, TotalBlocks);
 314         else
 315           DataflashManager_WriteBlocks(MSInterfaceInfo, BlockAddress, TotalBlocks);
 316
 317         /* Update the bytes transferred counter and succeed the command */
 318         MSInterfaceInfo->State.CommandBlock.DataTransferLength -= ((uint32_t)TotalBlocks * VIRTUAL_MEMORY_BLOCK_SIZE);
 319
 320         return true;
 321 }
 322
 323 /** Command processing for an issued SCSI MODE SENSE (6) command. This command returns various informational pages about
 324  *  the SCSI device, as well as the device's Write Protect status.
 325  *
 326  *  \param[in] MSInterfaceInfo  Pointer to the Mass Storage class interface structure that the command is associated with
 327  *
 328  *  \return Boolean \c true if the command completed successfully, \c false otherwise.
 329  */
 330 static bool SCSI_Command_ModeSense_6(USB_ClassInfo_MS_Device_t* const MSInterfaceInfo)
 331 {
 332         /* Send an empty header response with the Write Protect flag status */
 333         Endpoint_Write_8(0x00);
 334         Endpoint_Write_8(0x00);
 335         Endpoint_Write_8(DISK_READ_ONLY ? 0x80 : 0x00);
 336         Endpoint_Write_8(0x00);
 337         Endpoint_ClearIN();
 338
 339         /* Update the bytes transferred counter and succeed the command */
 340         MSInterfaceInfo->State.CommandBlock.DataTransferLength -= 4;
 341
 342         return true;
 343 }
 344