scsi: add request parsing helpers to common code.

Add helper functions for scsi request parsing to common code.  Getting
command length, transfer size, and linear block address is handled.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
This commit is contained in:
Gerd Hoffmann 2009-11-26 15:33:55 +01:00 committed by Anthony Liguori
parent 913766563f
commit 2ec749cb82
3 changed files with 191 additions and 132 deletions

View File

@ -1,6 +1,7 @@
#include "hw.h"
#include "sysemu.h"
#include "scsi.h"
#include "scsi-defs.h"
#include "block.h"
#include "qdev.h"
@ -142,3 +143,166 @@ void scsi_req_free(SCSIRequest *req)
QTAILQ_REMOVE(&req->dev->requests, req, next);
qemu_free(req);
}
static int scsi_req_length(SCSIRequest *req, uint8_t *cmd)
{
switch (cmd[0] >> 5) {
case 0:
req->cmd.xfer = cmd[4];
req->cmd.len = 6;
/* length 0 means 256 blocks */
if (req->cmd.xfer == 0)
req->cmd.xfer = 256;
break;
case 1:
case 2:
req->cmd.xfer = cmd[8] | (cmd[7] << 8);
req->cmd.len = 10;
break;
case 4:
req->cmd.xfer = cmd[13] | (cmd[12] << 8) | (cmd[11] << 16) | (cmd[10] << 24);
req->cmd.len = 16;
break;
case 5:
req->cmd.xfer = cmd[9] | (cmd[8] << 8) | (cmd[7] << 16) | (cmd[6] << 24);
req->cmd.len = 12;
break;
default:
return -1;
}
switch(cmd[0]) {
case TEST_UNIT_READY:
case REZERO_UNIT:
case START_STOP:
case SEEK_6:
case WRITE_FILEMARKS:
case SPACE:
case ERASE:
case ALLOW_MEDIUM_REMOVAL:
case VERIFY:
case SEEK_10:
case SYNCHRONIZE_CACHE:
case LOCK_UNLOCK_CACHE:
case LOAD_UNLOAD:
case SET_CD_SPEED:
case SET_LIMITS:
case WRITE_LONG:
case MOVE_MEDIUM:
case UPDATE_BLOCK:
req->cmd.xfer = 0;
break;
case MODE_SENSE:
break;
case WRITE_SAME:
req->cmd.xfer = 1;
break;
case READ_CAPACITY:
req->cmd.xfer = 8;
break;
case READ_BLOCK_LIMITS:
req->cmd.xfer = 6;
break;
case READ_POSITION:
req->cmd.xfer = 20;
break;
case SEND_VOLUME_TAG:
req->cmd.xfer *= 40;
break;
case MEDIUM_SCAN:
req->cmd.xfer *= 8;
break;
case WRITE_10:
case WRITE_VERIFY:
case WRITE_6:
case WRITE_12:
case WRITE_VERIFY_12:
req->cmd.xfer *= req->dev->blocksize;
break;
case READ_10:
case READ_6:
case READ_REVERSE:
case RECOVER_BUFFERED_DATA:
case READ_12:
req->cmd.xfer *= req->dev->blocksize;
break;
case INQUIRY:
req->cmd.xfer = cmd[4] | (cmd[3] << 8);
break;
}
return 0;
}
static int scsi_req_stream_length(SCSIRequest *req, uint8_t *cmd)
{
switch(cmd[0]) {
/* stream commands */
case READ_6:
case READ_REVERSE:
case RECOVER_BUFFERED_DATA:
case WRITE_6:
req->cmd.len = 6;
req->cmd.xfer = cmd[4] | (cmd[3] << 8) | (cmd[2] << 16);
if (cmd[1] & 0x01) /* fixed */
req->cmd.xfer *= req->dev->blocksize;
break;
case REWIND:
case START_STOP:
req->cmd.len = 6;
req->cmd.xfer = 0;
break;
/* generic commands */
default:
return scsi_req_length(req, cmd);
}
return 0;
}
static uint64_t scsi_req_lba(SCSIRequest *req)
{
uint8_t *buf = req->cmd.buf;
uint64_t lba;
switch (buf[0] >> 5) {
case 0:
lba = (uint64_t) buf[3] | ((uint64_t) buf[2] << 8) |
(((uint64_t) buf[1] & 0x1f) << 16);
break;
case 1:
case 2:
lba = (uint64_t) buf[5] | ((uint64_t) buf[4] << 8) |
((uint64_t) buf[3] << 16) | ((uint64_t) buf[2] << 24);
break;
case 4:
lba = (uint64_t) buf[9] | ((uint64_t) buf[8] << 8) |
((uint64_t) buf[7] << 16) | ((uint64_t) buf[6] << 24) |
((uint64_t) buf[5] << 32) | ((uint64_t) buf[4] << 40) |
((uint64_t) buf[3] << 48) | ((uint64_t) buf[2] << 56);
break;
case 5:
lba = (uint64_t) buf[5] | ((uint64_t) buf[4] << 8) |
((uint64_t) buf[3] << 16) | ((uint64_t) buf[2] << 24);
break;
default:
lba = -1;
}
return lba;
}
int scsi_req_parse(SCSIRequest *req, uint8_t *buf)
{
int rc;
if (req->dev->type == TYPE_TAPE) {
rc = scsi_req_stream_length(req, buf);
} else {
rc = scsi_req_length(req, buf);
}
if (rc != 0)
return rc;
memcpy(req->cmd.buf, buf, req->cmd.len);
req->cmd.lba = scsi_req_lba(req);
return 0;
}

View File

@ -288,121 +288,23 @@ static uint8_t *scsi_get_buf(SCSIDevice *d, uint32_t tag)
return r->buf;
}
static int scsi_length(uint8_t *cmd, int blocksize, int *cmdlen, uint32_t *len)
static void scsi_req_fixup(SCSIRequest *req)
{
switch (cmd[0] >> 5) {
case 0:
*len = cmd[4];
*cmdlen = 6;
/* length 0 means 256 blocks */
if (*len == 0)
*len = 256;
break;
case 1:
case 2:
*len = cmd[8] | (cmd[7] << 8);
*cmdlen = 10;
break;
case 4:
*len = cmd[13] | (cmd[12] << 8) | (cmd[11] << 16) | (cmd[10] << 24);
*cmdlen = 16;
break;
case 5:
*len = cmd[9] | (cmd[8] << 8) | (cmd[7] << 16) | (cmd[6] << 24);
*cmdlen = 12;
break;
default:
return -1;
}
switch(cmd[0]) {
case TEST_UNIT_READY:
case REZERO_UNIT:
case START_STOP:
case SEEK_6:
case WRITE_FILEMARKS:
case SPACE:
case ERASE:
case ALLOW_MEDIUM_REMOVAL:
case VERIFY:
case SEEK_10:
case SYNCHRONIZE_CACHE:
case LOCK_UNLOCK_CACHE:
case LOAD_UNLOAD:
case SET_CD_SPEED:
case SET_LIMITS:
case WRITE_LONG:
case MOVE_MEDIUM:
case UPDATE_BLOCK:
*len = 0;
break;
case MODE_SENSE:
break;
case WRITE_SAME:
*len = 1;
break;
case READ_CAPACITY:
*len = 8;
break;
case READ_BLOCK_LIMITS:
*len = 6;
break;
case READ_POSITION:
*len = 20;
break;
case SEND_VOLUME_TAG:
*len *= 40;
break;
case MEDIUM_SCAN:
*len *= 8;
break;
switch(req->cmd.buf[0]) {
case WRITE_10:
cmd[1] &= ~0x08; /* disable FUA */
case WRITE_VERIFY:
case WRITE_6:
case WRITE_12:
case WRITE_VERIFY_12:
*len *= blocksize;
req->cmd.buf[1] &= ~0x08; /* disable FUA */
break;
case READ_10:
cmd[1] &= ~0x08; /* disable FUA */
case READ_6:
case READ_REVERSE:
case RECOVER_BUFFERED_DATA:
case READ_12:
*len *= blocksize;
break;
case INQUIRY:
*len = cmd[4] | (cmd[3] << 8);
break;
}
return 0;
}
static int scsi_stream_length(uint8_t *cmd, int blocksize, int *cmdlen, uint32_t *len)
{
switch(cmd[0]) {
/* stream commands */
case READ_6:
case READ_REVERSE:
case RECOVER_BUFFERED_DATA:
case WRITE_6:
*cmdlen = 6;
*len = cmd[4] | (cmd[3] << 8) | (cmd[2] << 16);
if (cmd[1] & 0x01) /* fixed */
*len *= blocksize;
req->cmd.buf[1] &= ~0x08; /* disable FUA */
break;
case REWIND:
case START_STOP:
*cmdlen = 6;
*len = 0;
cmd[1] = 0x01; /* force IMMED, otherwise qemu waits end of command */
if (req->dev->type == TYPE_TAPE) {
/* force IMMED, otherwise qemu waits end of command */
req->cmd.buf[1] = 0x01;
}
break;
/* generic commands */
default:
return scsi_length(cmd, blocksize, cmdlen, len);
}
return 0;
}
static int is_write(int command)
@ -452,27 +354,10 @@ static int32_t scsi_send_command(SCSIDevice *d, uint32_t tag,
uint8_t *cmd, int lun)
{
SCSIGenericState *s = DO_UPCAST(SCSIGenericState, qdev, d);
uint32_t len=0;
int cmdlen=0;
SCSIGenericReq *r;
SCSIBus *bus;
int ret;
if (s->qdev.type == TYPE_TAPE) {
if (scsi_stream_length(cmd, s->qdev.blocksize, &cmdlen, &len) == -1) {
BADF("Unsupported command length, command %x\n", cmd[0]);
return 0;
}
} else {
if (scsi_length(cmd, s->qdev.blocksize, &cmdlen, &len) == -1) {
BADF("Unsupported command length, command %x\n", cmd[0]);
return 0;
}
}
DPRINTF("Command: lun=%d tag=0x%x data=0x%02x len %d\n", lun, tag,
cmd[0], len);
if (cmd[0] != REQUEST_SENSE &&
(lun != s->lun || (cmd[1] >> 5) != s->lun)) {
DPRINTF("Unimplemented LUN %d\n", lun ? lun : cmd[1] >> 5);
@ -498,10 +383,17 @@ static int32_t scsi_send_command(SCSIDevice *d, uint32_t tag,
}
r = scsi_new_request(d, tag, lun);
memcpy(r->req.cmd.buf, cmd, cmdlen);
r->req.cmd.len = cmdlen;
if (-1 == scsi_req_parse(&r->req, cmd)) {
BADF("Unsupported command length, command %x\n", cmd[0]);
scsi_remove_request(r);
return 0;
}
scsi_req_fixup(&r->req);
if (len == 0) {
DPRINTF("Command: lun=%d tag=0x%x data=0x%02x len %d\n", lun, tag,
cmd[0], r->req.cmd.xfer);
if (r->req.cmd.xfer == 0) {
if (r->buf != NULL)
qemu_free(r->buf);
r->buflen = 0;
@ -514,21 +406,21 @@ static int32_t scsi_send_command(SCSIDevice *d, uint32_t tag,
return 0;
}
if (r->buflen != len) {
if (r->buflen != r->req.cmd.xfer) {
if (r->buf != NULL)
qemu_free(r->buf);
r->buf = qemu_malloc(len);
r->buflen = len;
r->buf = qemu_malloc(r->req.cmd.xfer);
r->buflen = r->req.cmd.xfer;
}
memset(r->buf, 0, r->buflen);
r->len = len;
r->len = r->req.cmd.xfer;
if (is_write(cmd[0])) {
r->len = 0;
return -len;
return -r->req.cmd.xfer;
}
return len;
return r->req.cmd.xfer;
}
static int get_blocksize(BlockDriverState *bdrv)

View File

@ -26,6 +26,8 @@ typedef struct SCSIRequest {
struct {
uint8_t buf[SCSI_CMD_BUF_SIZE];
int len;
size_t xfer;
uint64_t lba;
} cmd;
BlockDriverAIOCB *aiocb;
QTAILQ_ENTRY(SCSIRequest) next;
@ -86,5 +88,6 @@ void scsi_bus_legacy_handle_cmdline(SCSIBus *bus);
SCSIRequest *scsi_req_alloc(size_t size, SCSIDevice *d, uint32_t tag, uint32_t lun);
SCSIRequest *scsi_req_find(SCSIDevice *d, uint32_t tag);
void scsi_req_free(SCSIRequest *req);
int scsi_req_parse(SCSIRequest *req, uint8_t *buf);
#endif