ref: 52cacba37c6f3a125ef931afa4b9c2cdb7438fef
dir: /sys/src/cmd/scuzz/scsireq.c/
#include <u.h>
#include <libc.h>
/*
* BUGS:
* no luns
* and incomplete in many other ways
*/
#include "scsireq.h"
enum {
Debug = 0,
};
/*
* exabyte tape drives, at least old ones like the 8200 and 8505,
* are dumb: you have to read the exact block size on the tape,
* they don't take 10-byte SCSI commands, and various other fine points.
*/
extern int exabyte, force6bytecmds;
static int debug = Debug;
long
SRready(ScsiReq *rp)
{
uchar cmd[6];
memset(cmd, 0, sizeof cmd);
rp->cmd.p = cmd;
rp->cmd.count = sizeof cmd;
rp->data.p = cmd;
rp->data.count = 0;
rp->data.write = 1;
return SRrequest(rp);
}
long
SRrewind(ScsiReq *rp)
{
uchar cmd[6];
memset(cmd, 0, sizeof cmd);
cmd[0] = ScmdRewind;
rp->cmd.p = cmd;
rp->cmd.count = sizeof cmd;
rp->data.p = cmd;
rp->data.count = 0;
rp->data.write = 1;
if(SRrequest(rp) >= 0){
rp->offset = 0;
return 0;
}
return -1;
}
long
SRreqsense(ScsiReq *rp)
{
uchar cmd[6];
ScsiReq req;
long status;
if(rp->status == Status_SD){
rp->status = STok;
return 0;
}
memset(cmd, 0, sizeof cmd);
cmd[0] = ScmdRsense;
cmd[4] = sizeof(req.sense);
memset(&req, 0, sizeof(req));
if(rp->flags&Fusb)
req.flags |= Fusb;
req.fd = rp->fd;
req.umsc = rp->umsc;
req.cmd.p = cmd;
req.cmd.count = sizeof cmd;
req.data.p = rp->sense;
req.data.count = sizeof(rp->sense);
req.data.write = 0;
status = SRrequest(&req);
rp->status = req.status;
return status;
}
long
SRformat(ScsiReq *rp)
{
uchar cmd[6];
memset(cmd, 0, sizeof cmd);
cmd[0] = ScmdFormat;
rp->cmd.p = cmd;
rp->cmd.count = sizeof cmd;
rp->data.p = cmd;
rp->data.count = 6;
rp->data.write = 0;
return SRrequest(rp);
}
long
SRrblimits(ScsiReq *rp, uchar *list)
{
uchar cmd[6];
memset(cmd, 0, sizeof cmd);
cmd[0] = ScmdRblimits;
rp->cmd.p = cmd;
rp->cmd.count = sizeof cmd;
rp->data.p = list;
rp->data.count = 6;
rp->data.write = 0;
return SRrequest(rp);
}
static int
dirdevrw(ScsiReq *rp, uchar *cmd, long nbytes)
{
long n;
n = nbytes / rp->lbsize;
if(rp->offset <= Max24off && n <= 256 && (rp->flags & Frw10) == 0){
PUTBE24(cmd+1, rp->offset);
cmd[4] = n;
cmd[5] = 0;
return 6;
}
cmd[0] |= ScmdExtread;
cmd[1] = 0;
PUTBELONG(cmd+2, rp->offset);
cmd[6] = 0;
cmd[7] = n>>8;
cmd[8] = n;
cmd[9] = 0;
return 10;
}
static int
seqdevrw(ScsiReq *rp, uchar *cmd, long nbytes)
{
long n;
/* don't set Cmd1sili; we want the ILI bit instead of a fatal error */
cmd[1] = rp->flags&Fbfixed? Cmd1fixed: 0;
n = nbytes / rp->lbsize;
PUTBE24(cmd+2, n);
cmd[5] = 0;
return 6;
}
long
SRread(ScsiReq *rp, void *buf, long nbytes)
{
uchar cmd[10];
long n;
if((nbytes % rp->lbsize) || nbytes > maxiosize){
if(debug)
if (nbytes % rp->lbsize)
fprint(2, "scuzz: i/o size %ld %% %ld != 0\n",
nbytes, rp->lbsize);
else
fprint(2, "scuzz: i/o size %ld > %ld\n",
nbytes, maxiosize);
rp->status = Status_BADARG;
return -1;
}
/* set up scsi read cmd */
cmd[0] = ScmdRead;
if(rp->flags & Fseqdev)
rp->cmd.count = seqdevrw(rp, cmd, nbytes);
else
rp->cmd.count = dirdevrw(rp, cmd, nbytes);
rp->cmd.p = cmd;
rp->data.p = buf;
rp->data.count = nbytes;
rp->data.write = 0;
/* issue it */
n = SRrequest(rp);
if(n != -1){ /* it worked? */
rp->offset += n / rp->lbsize;
return n;
}
/* request failed; maybe we just read a short record? */
if (exabyte) {
fprint(2, "read error\n");
rp->status = STcheck;
return n;
}
if(rp->status != Status_SD || !(rp->sense[0] & Sd0valid))
return -1;
/* compute # of bytes not read */
n = GETBELONG(rp->sense+3) * rp->lbsize;
if (debug)
fprint(2,
"SRread: request failed with sense data; sense byte count %ld\n",
n);
if(!(rp->flags & Fseqdev))
return -1;
/* device is a tape or something similar */
if (rp->sense[2] == Sd2filemark || rp->sense[2] == 0x08 ||
rp->sense[2] & Sd2ili && n > 0)
rp->data.count = nbytes - n;
else
return -1;
n = rp->data.count;
if (!rp->readblock++ || debug)
fprint(2, "SRread: tape data count %ld%s\n", n,
(rp->sense[2] & Sd2ili? " with ILI": ""));
rp->status = STok;
rp->offset += n / rp->lbsize;
return n;
}
long
SRwrite(ScsiReq *rp, void *buf, long nbytes)
{
uchar cmd[10];
long n;
if((nbytes % rp->lbsize) || nbytes > maxiosize){
if(debug)
if (nbytes % rp->lbsize)
fprint(2, "scuzz: i/o size %ld %% %ld != 0\n",
nbytes, rp->lbsize);
else
fprint(2, "scuzz: i/o size %ld > %ld\n",
nbytes, maxiosize);
rp->status = Status_BADARG;
return -1;
}
/* set up scsi write cmd */
cmd[0] = ScmdWrite;
if(rp->flags & Fseqdev)
rp->cmd.count = seqdevrw(rp, cmd, nbytes);
else
rp->cmd.count = dirdevrw(rp, cmd, nbytes);
rp->cmd.p = cmd;
rp->data.p = buf;
rp->data.count = nbytes;
rp->data.write = 1;
/* issue it */
if((n = SRrequest(rp)) == -1){
if (exabyte) {
fprint(2, "write error\n");
rp->status = STcheck;
return n;
}
if(rp->status != Status_SD || rp->sense[2] != Sd2eom)
return -1;
if(rp->sense[0] & Sd0valid){
n -= GETBELONG(rp->sense+3) * rp->lbsize;
rp->data.count = nbytes - n;
}
else
rp->data.count = nbytes;
n = rp->data.count;
}
rp->offset += n / rp->lbsize;
return n;
}
long
SRseek(ScsiReq *rp, long offset, int type)
{
uchar cmd[10];
switch(type){
case 0:
break;
case 1:
offset += rp->offset;
if(offset >= 0)
break;
/*FALLTHROUGH*/
default:
if(debug)
fprint(2, "scuzz: seek failed\n");
rp->status = Status_BADARG;
return -1;
}
memset(cmd, 0, sizeof cmd);
if(offset <= Max24off && (rp->flags & Frw10) == 0){
cmd[0] = ScmdSeek;
PUTBE24(cmd+1, offset & Max24off);
rp->cmd.count = 6;
}else{
cmd[0] = ScmdExtseek;
PUTBELONG(cmd+2, offset);
rp->cmd.count = 10;
}
rp->cmd.p = cmd;
rp->data.p = cmd;
rp->data.count = 0;
rp->data.write = 1;
SRrequest(rp);
if(rp->status == STok)
return rp->offset = offset;
return -1;
}
long
SRfilemark(ScsiReq *rp, ulong howmany)
{
uchar cmd[6];
memset(cmd, 0, sizeof cmd);
cmd[0] = ScmdFmark;
PUTBE24(cmd+2, howmany);
rp->cmd.p = cmd;
rp->cmd.count = sizeof cmd;
rp->data.p = cmd;
rp->data.count = 0;
rp->data.write = 1;
return SRrequest(rp);
}
long
SRspace(ScsiReq *rp, uchar code, long howmany)
{
uchar cmd[6];
memset(cmd, 0, sizeof cmd);
cmd[0] = ScmdSpace;
cmd[1] = code;
PUTBE24(cmd+2, howmany);
rp->cmd.p = cmd;
rp->cmd.count = sizeof cmd;
rp->data.p = cmd;
rp->data.count = 0;
rp->data.write = 1;
/*
* what about rp->offset?
*/
return SRrequest(rp);
}
long
SRinquiry(ScsiReq *rp)
{
uchar cmd[6];
memset(cmd, 0, sizeof cmd);
cmd[0] = ScmdInq;
cmd[4] = sizeof rp->inquiry;
rp->cmd.p = cmd;
rp->cmd.count = sizeof cmd;
memset(rp->inquiry, 0, sizeof rp->inquiry);
rp->data.p = rp->inquiry;
rp->data.count = sizeof rp->inquiry;
rp->data.write = 0;
if(SRrequest(rp) >= 0){
rp->flags |= Finqok;
return 0;
}
rp->flags &= ~Finqok;
return -1;
}
long
SRmodeselect6(ScsiReq *rp, uchar *list, long nbytes)
{
uchar cmd[6];
memset(cmd, 0, sizeof cmd);
cmd[0] = ScmdMselect6;
if((rp->flags & Finqok) && (rp->inquiry[2] & 0x07) >= 2)
cmd[1] = 0x10;
cmd[4] = nbytes;
rp->cmd.p = cmd;
rp->cmd.count = sizeof cmd;
rp->data.p = list;
rp->data.count = nbytes;
rp->data.write = 1;
return SRrequest(rp);
}
long
SRmodeselect10(ScsiReq *rp, uchar *list, long nbytes)
{
uchar cmd[10];
memset(cmd, 0, sizeof cmd);
if((rp->flags & Finqok) && (rp->inquiry[2] & 0x07) >= 2)
cmd[1] = 0x10;
cmd[0] = ScmdMselect10;
cmd[7] = nbytes>>8;
cmd[8] = nbytes;
rp->cmd.p = cmd;
rp->cmd.count = sizeof cmd;
rp->data.p = list;
rp->data.count = nbytes;
rp->data.write = 1;
return SRrequest(rp);
}
long
SRmodesense6(ScsiReq *rp, uchar page, uchar *list, long nbytes)
{
uchar cmd[6];
memset(cmd, 0, sizeof cmd);
cmd[0] = ScmdMsense6;
cmd[2] = page;
cmd[4] = nbytes;
rp->cmd.p = cmd;
rp->cmd.count = sizeof cmd;
rp->data.p = list;
rp->data.count = nbytes;
rp->data.write = 0;
return SRrequest(rp);
}
long
SRmodesense10(ScsiReq *rp, uchar page, uchar *list, long nbytes)
{
uchar cmd[10];
memset(cmd, 0, sizeof cmd);
cmd[0] = ScmdMsense10;
cmd[2] = page;
cmd[7] = nbytes>>8;
cmd[8] = nbytes;
rp->cmd.p = cmd;
rp->cmd.count = sizeof cmd;
rp->data.p = list;
rp->data.count = nbytes;
rp->data.write = 0;
return SRrequest(rp);
}
long
SRstart(ScsiReq *rp, uchar code)
{
uchar cmd[6];
memset(cmd, 0, sizeof cmd);
cmd[0] = ScmdStart;
cmd[4] = code;
rp->cmd.p = cmd;
rp->cmd.count = sizeof cmd;
rp->data.p = cmd;
rp->data.count = 0;
rp->data.write = 1;
return SRrequest(rp);
}
long
SRrcapacity(ScsiReq *rp, uchar *data)
{
uchar cmd[10];
memset(cmd, 0, sizeof cmd);
cmd[0] = ScmdRcapacity;
rp->cmd.p = cmd;
rp->cmd.count = sizeof cmd;
rp->data.p = data;
rp->data.count = 8;
rp->data.write = 0;
return SRrequest(rp);
}
static long
request(int fd, ScsiPtr *cmd, ScsiPtr *data, int *status)
{
long n, r;
char buf[16];
/* this was an experiment but it seems to be a good idea */
*status = STok;
/* send SCSI command */
if(write(fd, cmd->p, cmd->count) != cmd->count){
fprint(2, "scsireq: write cmd: %r\n");
*status = Status_SW;
return -1;
}
/* read or write actual data */
werrstr("");
if(data->write)
n = write(fd, data->p, data->count);
else {
n = read(fd, data->p, data->count);
if (n < 0)
memset(data->p, 0, data->count);
else if (n < data->count)
memset(data->p + n, 0, data->count - n);
}
if (n != data->count && n <= 0) {
if (debug)
fprint(2,
"request: tried to %s %ld bytes of data for cmd 0x%x but got %r\n",
(data->write? "write": "read"),
data->count, cmd->p[0]);
} else if (n != data->count && (data->write || debug))
fprint(2, "request: %s %ld of %ld bytes of actual data\n",
(data->write? "wrote": "read"), n, data->count);
/* read status */
buf[0] = '\0';
r = read(fd, buf, sizeof buf-1);
if(exabyte && r <= 0 || !exabyte && r < 0){
fprint(2, "scsireq: read status: %r\n");
*status = Status_SW;
return -1;
}
if (r >= 0)
buf[r] = '\0';
*status = atoi(buf);
if(n < 0 && (exabyte || *status != STcheck))
fprint(2, "scsireq: status 0x%2.2uX: data transfer: %r\n",
*status);
return n;
}
long
SRrequest(ScsiReq *rp)
{
long n;
int status;
retry:
if(rp->flags&Fusb)
n = umsrequest(rp->umsc, &rp->cmd, &rp->data, &status);
else
n = request(rp->fd, &rp->cmd, &rp->data, &status);
switch(rp->status = status){
case STok:
rp->data.count = n;
break;
case STcheck:
if(rp->cmd.p[0] != ScmdRsense && SRreqsense(rp) != -1)
rp->status = Status_SD;
if (exabyte)
fprint(2, "SRrequest: STcheck, returning -1\n");
return -1;
case STbusy:
sleep(1000);
goto retry;
default:
fprint(2, "status 0x%2.2uX\n", status);
return -1;
}
return n;
}
int
SRclose(ScsiReq *rp)
{
if((rp->flags & Fopen) == 0){
if(debug)
fprint(2, "scuzz: closing closed file\n");
rp->status = Status_BADARG;
return -1;
}
close(rp->fd);
rp->flags = 0;
return 0;
}
uint
mkascq(ScsiReq *r)
{
uchar *u;
u = r->sense;
return u[2]<<16 | u[12]<<8 | u[13];
}
static int
dirdevopen(ScsiReq *rp)
{
ulong blocks;
uchar data[8];
if(SRstart(rp, 1) == -1)
/*
* it's okay for removable media to say
* "check condition: medium not present".
* 3a is "medium not present".
*/
return rp->inquiry[1] & 0x80 && (mkascq(rp) >> 8) == 0x023a?
0: -1;
memset(data, 0, sizeof data);
if(SRrcapacity(rp, data) == -1)
return -1;
rp->lbsize = GETBELONG(data+4);
blocks = GETBELONG(data);
if(debug)
fprint(2, "scuzz: dirdevopen: logical block size %lud, "
"# blocks %lud\n", rp->lbsize, blocks);
/* some newer dev's don't support 6-byte commands */
if(blocks > Max24off && !force6bytecmds)
rp->flags |= Frw10;
return 0;
}
static int
seqdevopen(ScsiReq *rp)
{
uchar mode[16], limits[6];
if(SRrblimits(rp, limits) == -1)
return -1;
if(limits[1] == 0 && limits[2] == limits[4] && limits[3] == limits[5]){
rp->flags |= Fbfixed;
rp->lbsize = limits[4]<<8 | limits[5];
if(debug)
fprint(2, "scuzz: seqdevopen: logical block size %lud\n",
rp->lbsize);
return 0;
}
/*
* On some older hardware the optional 10-byte
* modeselect command isn't implemented.
*/
if (force6bytecmds)
rp->flags |= Fmode6;
if(!(rp->flags & Fmode6)){
/* try 10-byte command first */
memset(mode, 0, sizeof mode);
mode[3] = 0x10; /* device-specific param. */
mode[7] = 8; /* block descriptor length */
/*
* exabytes can't handle this, and
* modeselect(10) is optional.
*/
if(SRmodeselect10(rp, mode, sizeof mode) != -1){
rp->lbsize = 1;
return 0; /* success */
}
/* can't do 10-byte commands, back off to 6-byte ones */
rp->flags |= Fmode6;
}
/* 6-byte command */
memset(mode, 0, sizeof mode);
mode[2] = 0x10; /* device-specific param. */
mode[3] = 8; /* block descriptor length */
/*
* bsd sez exabytes need this bit (NBE: no busy enable) in
* vendor-specific page (0), but so far we haven't needed it.
mode[12] |= 8;
*/
if(SRmodeselect6(rp, mode, 4+8) == -1)
return -1;
rp->lbsize = 1;
return 0;
}
static int
wormdevopen(ScsiReq *rp)
{
long status;
uchar list[MaxDirData];
if (SRstart(rp, 1) == -1 ||
(status = SRmodesense10(rp, Allmodepages, list, sizeof list)) == -1)
return -1;
/* nbytes = list[0]<<8 | list[1]; */
/* # of bytes of block descriptors of 8 bytes each; not even 1? */
if((list[6]<<8 | list[7]) < 8)
rp->lbsize = 2048;
else
/* last 3 bytes of block 0 descriptor */
rp->lbsize = GETBE24(list+13);
if(debug)
fprint(2, "scuzz: wormdevopen: logical block size %lud\n",
rp->lbsize);
return status;
}
int
SRopenraw(ScsiReq *rp, char *unit)
{
char name[128];
if(rp->flags & Fopen){
if(debug)
fprint(2, "scuzz: opening open file\n");
rp->status = Status_BADARG;
return -1;
}
memset(rp, 0, sizeof *rp);
rp->unit = unit;
sprint(name, "%s/raw", unit);
if((rp->fd = open(name, ORDWR)) == -1){
rp->status = STtimeout;
return -1;
}
rp->flags = Fopen;
return 0;
}
int
SRopen(ScsiReq *rp, char *unit)
{
if(SRopenraw(rp, unit) == -1)
return -1;
SRready(rp);
if(SRinquiry(rp) >= 0){
switch(rp->inquiry[0]){
default:
fprint(2, "unknown device type 0x%.2x\n", rp->inquiry[0]);
rp->status = Status_SW;
break;
case 0x00: /* Direct access (disk) */
case 0x05: /* CD-ROM */
case 0x07: /* rewriteable MO */
if(dirdevopen(rp) == -1)
break;
return 0;
case 0x01: /* Sequential eg: tape */
rp->flags |= Fseqdev;
if(seqdevopen(rp) == -1)
break;
return 0;
case 0x02: /* Printer */
rp->flags |= Fprintdev;
return 0;
case 0x04: /* Worm */
rp->flags |= Fwormdev;
if(wormdevopen(rp) == -1)
break;
return 0;
case 0x08: /* medium-changer */
rp->flags |= Fchanger;
return 0;
}
}
SRclose(rp);
return -1;
}