Intento emitir un scsileer (10) yescribir (10) a un SSD. yo sueloeste código de ejemplo Como referencia / código básico.

Esta es mi lectura de scsi:

#define READ_REPLY_LEN 32
#define READ_CMDLEN 10
void scsi_read()
{
  unsigned char Readbuffer[ SCSI_OFF + READ_REPLY_LEN ];
  unsigned char cmdblk [ READ_CMDLEN ] =
      {        0x28,  /* command */
                  0,  /* lun/reserved */
                  0,  /* lba */
                  0,  /* lba */
                  0,  /* lba */
                  0,  /* lba */
                  0,  /* reserved */
                  0,  /* transfer length */
     READ_REPLY_LEN,  /* transfer length */
                  0 };/* reserved/flag/link */
  memset(Readbuffer,0,sizeof(Readbuffer));
  memcpy( cmd + SCSI_OFF, cmdblk, sizeof(cmdblk) );

  /*
   * +------------------+
   * | struct sg_header | <- cmd
   * +------------------+
   * | copy of cmdblk   | <- cmd + SCSI_OFF
   * +------------------+
   */

  if (handle_scsi_cmd(sizeof(cmdblk), 0, cmd,
                      sizeof(Readbuffer) - SCSI_OFF, Readbuffer )) {
      fprintf( stderr, "read failed\n" );
      exit(2);
  }
  hex_dump(Readbuffer,sizeof(Readbuffer));
}

Y este es mi scsi escribe:

void scsi_write ( void )
{
  unsigned char Writebuffer[SCSI_OFF];
  unsigned char cmdblk [] =
      {        0x2A,  /* 0: command */
                  0,  /* 1: lun/reserved */
                  0,  /* 2: LBA */
                  0,  /* 3: LBA */
                  0,  /* 4: LBA */
                  0,  /* 5: LBA */
                  0,  /* 6: reserved */
                  0,  /* 7: transfer length */
                  0,  /* 8: transfer length */
                  0 };/* 9: control */

  memset(Writebuffer,0,sizeof(Writebuffer));
  memcpy( cmd + SCSI_OFF, cmdblk, sizeof(cmdblk) );
  cmd[SCSI_OFF+sizeof(cmdblk)+0] = 'A';
  cmd[SCSI_OFF+sizeof(cmdblk)+1] = 'b';
  cmd[SCSI_OFF+sizeof(cmdblk)+2] = 'c';
  cmd[SCSI_OFF+sizeof(cmdblk)+3] = 'd';
  cmd[SCSI_OFF+sizeof(cmdblk)+4] = 'e';
  cmd[SCSI_OFF+sizeof(cmdblk)+5] = 'f';
  cmd[SCSI_OFF+sizeof(cmdblk)+6] = 'g';
  cmd[SCSI_OFF+sizeof(cmdblk)+7] = 0;
  /*
   * +------------------+
   * | struct sg_header | <- cmd
   * +------------------+
   * | copy of cmdblk   | <- cmd + SCSI_OFF
   * +------------------+
   * | data to write    | 
   * +------------------+
   */

  if (handle_scsi_cmd(sizeof(cmdblk), 8, cmd, 
                      sizeof(Writebuffer) - SCSI_OFF, Writebuffer )) {
      fprintf( stderr, "write failed\n" );
      exit(2);
  }
}

En el siguiente ejemplo hago

leer scsiscsi escribeleer scsi

E imprimo los volcados hexadecimales de los datos que se escriben (scsi write) y lo que se lee (scsi read)

Read(10)
[0000]   00 00 00 44 00 00 00 44   00 00 00 00 00 00 00 00   ...D...D ........
[0010]   00 2C 00 00 00 00 00 00   00 00 00 00 00 00 00 00   ........ ........
[0020]   00 00 00 00 00 00 00 00   00 00 00 00 00 00 00 00   ........ ........
[0030]   00 00 00 00 00 00 00 00   00 00 00 00 00 00 00 00   ........ ........
[0040]   00 00 00 00                                         ....

Write(10):
[0000]   00 00 00 00 00 00 00 24   00 00 00 00 00 00 00 00   ........ ........
[0010]   00 00 00 00 00 00 00 00   00 00 00 00 00 00 00 00   ........ ........
[0020]   00 00 00 00 2A 00 00 00   00 00 00 00 00 00 41 62   ........ ......Ab
[0030]   63 64 65 66 67 00                                   cdefg.

Read(10):
[0000]   00 00 00 44 00 00 00 44   00 00 00 00 00 00 00 00   ...D...D ........
[0010]   04 00 20 00 70 00 02 00   00 00 00 0A 00 00 00 00   ....p... ........
[0020]   04 00 00 00 41 62 63 64   65 66 67 00 00 00 00 00   ....Abcd efg.....
[0030]   00 00 00 00 00 00 00 00   00 00 00 00 00 00 00 00   ........ ........
[0040]   00 00 00 00                                         ....

Después de ejecutar los tres comandos otra vez, debería leerAbcdefg con la primera lectura. ¿Derecha? Pero ejecutarlos de nuevo no cambia nada. Ahora puede suponer que la memoria que utilizo aún tiene datos de funciones anteriores, pero obtengo el mismo resultado aunque ejecutomemset(Readbuff,0,sizeof(Readbuff)) antes desys_read() sucede

Supuse que el LBA que intento escribir está prohibido escribir, y leí el caché. Pero el hecho de interactuar con las direcciones de LBA de 0x00-0xFF no cambia nada. Eso significa que leí los mismos datos (Abcdefg).

¿Conoce una implementación de ejemplo de lectura o escritura de scsi con la interfaz genérica de scsi?