SCSI读取（10）和写入（10）与SCSI通用接口

我尝试发出scsi 读（10）并写入（10）到SSD。 我使用这个示例代码作为参考/基本代码。

这是我的scsi阅读：

#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)); } 

这是我的scsi写道：

 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); } } 

在下面的例子中，我做了

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• 在用户空间启用写入组合IO访问
• 从硬件本身查找原始MAC地址
• 如何在开机时将值传递给内build的Linux内核模块？
• 内核模块的内存使用情况

1. scsi读
2. scsi写
3. scsi读

我打印写入的数据（scsi写入）的hexdump和读取的内容（scsi读取）

 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 .... 

为了再次运行这三个命令，我应该先阅读Abcdefg 。 对？ 但是再次运行它们并没有改变。 你现在可以假设，我使用的内存仍然是以前的function的数据，但即使在sys_read()发生之前运行memset(Readbuff,0,sizeof(Readbuff))我也会得到相同的结果。

我认为，我试图写的LBA可能是禁止写的，我读了caching。 但是通过LBA地址从0x00-0xFF进行交换并不会改变 – 也就是说，我读取了相同的数据（ Abcdefg ）。

你知道scsi读写的一个示例实现吗？