372 lines
8.5 KiB
C
372 lines
8.5 KiB
C
/*
|
|
* Simulated SCSI driver.
|
|
*
|
|
* Copyright (C) 1999, 2001-2003 Hewlett-Packard Co
|
|
* David Mosberger-Tang <davidm@hpl.hp.com>
|
|
* Stephane Eranian <eranian@hpl.hp.com>
|
|
*
|
|
* 02/01/15 David Mosberger Updated for v2.5.1
|
|
* 99/12/18 David Mosberger Added support for READ10/WRITE10 needed by linux v2.3.33
|
|
*/
|
|
#include <linux/blkdev.h>
|
|
#include <linux/init.h>
|
|
#include <linux/interrupt.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/timer.h>
|
|
#include <asm/irq.h>
|
|
#include "hpsim_ssc.h"
|
|
|
|
#include <scsi/scsi.h>
|
|
#include <scsi/scsi_cmnd.h>
|
|
#include <scsi/scsi_device.h>
|
|
#include <scsi/scsi_host.h>
|
|
|
|
#define DEBUG_SIMSCSI 0
|
|
|
|
#define SIMSCSI_REQ_QUEUE_LEN 64
|
|
#define DEFAULT_SIMSCSI_ROOT "/var/ski-disks/sd"
|
|
|
|
/* Simulator system calls: */
|
|
|
|
#define SSC_OPEN 50
|
|
#define SSC_CLOSE 51
|
|
#define SSC_READ 52
|
|
#define SSC_WRITE 53
|
|
#define SSC_GET_COMPLETION 54
|
|
#define SSC_WAIT_COMPLETION 55
|
|
|
|
#define SSC_WRITE_ACCESS 2
|
|
#define SSC_READ_ACCESS 1
|
|
|
|
#if DEBUG_SIMSCSI
|
|
int simscsi_debug;
|
|
# define DBG simscsi_debug
|
|
#else
|
|
# define DBG 0
|
|
#endif
|
|
|
|
static struct Scsi_Host *host;
|
|
|
|
static void simscsi_interrupt (unsigned long val);
|
|
static DECLARE_TASKLET(simscsi_tasklet, simscsi_interrupt, 0);
|
|
|
|
struct disk_req {
|
|
unsigned long addr;
|
|
unsigned len;
|
|
};
|
|
|
|
struct disk_stat {
|
|
int fd;
|
|
unsigned count;
|
|
};
|
|
|
|
static int desc[16] = {
|
|
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1
|
|
};
|
|
|
|
static struct queue_entry {
|
|
struct scsi_cmnd *sc;
|
|
} queue[SIMSCSI_REQ_QUEUE_LEN];
|
|
|
|
static int rd, wr;
|
|
static atomic_t num_reqs = ATOMIC_INIT(0);
|
|
|
|
/* base name for default disks */
|
|
static char *simscsi_root = DEFAULT_SIMSCSI_ROOT;
|
|
|
|
#define MAX_ROOT_LEN 128
|
|
|
|
/*
|
|
* used to setup a new base for disk images
|
|
* to use /foo/bar/disk[a-z] as disk images
|
|
* you have to specify simscsi=/foo/bar/disk on the command line
|
|
*/
|
|
static int __init
|
|
simscsi_setup (char *s)
|
|
{
|
|
/* XXX Fix me we may need to strcpy() ? */
|
|
if (strlen(s) > MAX_ROOT_LEN) {
|
|
printk(KERN_ERR "simscsi_setup: prefix too long---using default %s\n",
|
|
simscsi_root);
|
|
} else
|
|
simscsi_root = s;
|
|
return 1;
|
|
}
|
|
|
|
__setup("simscsi=", simscsi_setup);
|
|
|
|
static void
|
|
simscsi_interrupt (unsigned long val)
|
|
{
|
|
struct scsi_cmnd *sc;
|
|
|
|
while ((sc = queue[rd].sc) != NULL) {
|
|
atomic_dec(&num_reqs);
|
|
queue[rd].sc = NULL;
|
|
if (DBG)
|
|
printk("simscsi_interrupt: done with %ld\n", sc->serial_number);
|
|
(*sc->scsi_done)(sc);
|
|
rd = (rd + 1) % SIMSCSI_REQ_QUEUE_LEN;
|
|
}
|
|
}
|
|
|
|
static int
|
|
simscsi_biosparam (struct scsi_device *sdev, struct block_device *n,
|
|
sector_t capacity, int ip[])
|
|
{
|
|
ip[0] = 64; /* heads */
|
|
ip[1] = 32; /* sectors */
|
|
ip[2] = capacity >> 11; /* cylinders */
|
|
return 0;
|
|
}
|
|
|
|
static void
|
|
simscsi_sg_readwrite (struct scsi_cmnd *sc, int mode, unsigned long offset)
|
|
{
|
|
int i;
|
|
struct scatterlist *sl;
|
|
struct disk_stat stat;
|
|
struct disk_req req;
|
|
|
|
stat.fd = desc[sc->device->id];
|
|
|
|
scsi_for_each_sg(sc, sl, scsi_sg_count(sc), i) {
|
|
req.addr = __pa(sg_virt(sl));
|
|
req.len = sl->length;
|
|
if (DBG)
|
|
printk("simscsi_sg_%s @ %lx (off %lx) use_sg=%d len=%d\n",
|
|
mode == SSC_READ ? "read":"write", req.addr, offset,
|
|
scsi_sg_count(sc) - i, sl->length);
|
|
ia64_ssc(stat.fd, 1, __pa(&req), offset, mode);
|
|
ia64_ssc(__pa(&stat), 0, 0, 0, SSC_WAIT_COMPLETION);
|
|
|
|
/* should not happen in our case */
|
|
if (stat.count != req.len) {
|
|
sc->result = DID_ERROR << 16;
|
|
return;
|
|
}
|
|
offset += sl->length;
|
|
}
|
|
sc->result = GOOD;
|
|
}
|
|
|
|
/*
|
|
* function handling both READ_6/WRITE_6 (non-scatter/gather mode)
|
|
* commands.
|
|
* Added 02/26/99 S.Eranian
|
|
*/
|
|
static void
|
|
simscsi_readwrite6 (struct scsi_cmnd *sc, int mode)
|
|
{
|
|
unsigned long offset;
|
|
|
|
offset = (((sc->cmnd[1] & 0x1f) << 16) | (sc->cmnd[2] << 8) | sc->cmnd[3])*512;
|
|
simscsi_sg_readwrite(sc, mode, offset);
|
|
}
|
|
|
|
static size_t
|
|
simscsi_get_disk_size (int fd)
|
|
{
|
|
struct disk_stat stat;
|
|
size_t bit, sectors = 0;
|
|
struct disk_req req;
|
|
char buf[512];
|
|
|
|
/*
|
|
* This is a bit kludgey: the simulator doesn't provide a
|
|
* direct way of determining the disk size, so we do a binary
|
|
* search, assuming a maximum disk size of 128GB.
|
|
*/
|
|
for (bit = (128UL << 30)/512; bit != 0; bit >>= 1) {
|
|
req.addr = __pa(&buf);
|
|
req.len = sizeof(buf);
|
|
ia64_ssc(fd, 1, __pa(&req), ((sectors | bit) - 1)*512, SSC_READ);
|
|
stat.fd = fd;
|
|
ia64_ssc(__pa(&stat), 0, 0, 0, SSC_WAIT_COMPLETION);
|
|
if (stat.count == sizeof(buf))
|
|
sectors |= bit;
|
|
}
|
|
return sectors - 1; /* return last valid sector number */
|
|
}
|
|
|
|
static void
|
|
simscsi_readwrite10 (struct scsi_cmnd *sc, int mode)
|
|
{
|
|
unsigned long offset;
|
|
|
|
offset = (((unsigned long)sc->cmnd[2] << 24)
|
|
| ((unsigned long)sc->cmnd[3] << 16)
|
|
| ((unsigned long)sc->cmnd[4] << 8)
|
|
| ((unsigned long)sc->cmnd[5] << 0))*512UL;
|
|
simscsi_sg_readwrite(sc, mode, offset);
|
|
}
|
|
|
|
static int
|
|
simscsi_queuecommand_lck (struct scsi_cmnd *sc, void (*done)(struct scsi_cmnd *))
|
|
{
|
|
unsigned int target_id = sc->device->id;
|
|
char fname[MAX_ROOT_LEN+16];
|
|
size_t disk_size;
|
|
char *buf;
|
|
char localbuf[36];
|
|
#if DEBUG_SIMSCSI
|
|
register long sp asm ("sp");
|
|
|
|
if (DBG)
|
|
printk("simscsi_queuecommand: target=%d,cmnd=%u,sc=%lu,sp=%lx,done=%p\n",
|
|
target_id, sc->cmnd[0], sc->serial_number, sp, done);
|
|
#endif
|
|
|
|
sc->result = DID_BAD_TARGET << 16;
|
|
sc->scsi_done = done;
|
|
if (target_id <= 15 && sc->device->lun == 0) {
|
|
switch (sc->cmnd[0]) {
|
|
case INQUIRY:
|
|
if (scsi_bufflen(sc) < 35) {
|
|
break;
|
|
}
|
|
sprintf (fname, "%s%c", simscsi_root, 'a' + target_id);
|
|
desc[target_id] = ia64_ssc(__pa(fname), SSC_READ_ACCESS|SSC_WRITE_ACCESS,
|
|
0, 0, SSC_OPEN);
|
|
if (desc[target_id] < 0) {
|
|
/* disk doesn't exist... */
|
|
break;
|
|
}
|
|
buf = localbuf;
|
|
buf[0] = 0; /* magnetic disk */
|
|
buf[1] = 0; /* not a removable medium */
|
|
buf[2] = 2; /* SCSI-2 compliant device */
|
|
buf[3] = 2; /* SCSI-2 response data format */
|
|
buf[4] = 31; /* additional length (bytes) */
|
|
buf[5] = 0; /* reserved */
|
|
buf[6] = 0; /* reserved */
|
|
buf[7] = 0; /* various flags */
|
|
memcpy(buf + 8, "HP SIMULATED DISK 0.00", 28);
|
|
scsi_sg_copy_from_buffer(sc, buf, 36);
|
|
sc->result = GOOD;
|
|
break;
|
|
|
|
case TEST_UNIT_READY:
|
|
sc->result = GOOD;
|
|
break;
|
|
|
|
case READ_6:
|
|
if (desc[target_id] < 0 )
|
|
break;
|
|
simscsi_readwrite6(sc, SSC_READ);
|
|
break;
|
|
|
|
case READ_10:
|
|
if (desc[target_id] < 0 )
|
|
break;
|
|
simscsi_readwrite10(sc, SSC_READ);
|
|
break;
|
|
|
|
case WRITE_6:
|
|
if (desc[target_id] < 0)
|
|
break;
|
|
simscsi_readwrite6(sc, SSC_WRITE);
|
|
break;
|
|
|
|
case WRITE_10:
|
|
if (desc[target_id] < 0)
|
|
break;
|
|
simscsi_readwrite10(sc, SSC_WRITE);
|
|
break;
|
|
|
|
case READ_CAPACITY:
|
|
if (desc[target_id] < 0 || scsi_bufflen(sc) < 8) {
|
|
break;
|
|
}
|
|
buf = localbuf;
|
|
disk_size = simscsi_get_disk_size(desc[target_id]);
|
|
|
|
buf[0] = (disk_size >> 24) & 0xff;
|
|
buf[1] = (disk_size >> 16) & 0xff;
|
|
buf[2] = (disk_size >> 8) & 0xff;
|
|
buf[3] = (disk_size >> 0) & 0xff;
|
|
/* set block size of 512 bytes: */
|
|
buf[4] = 0;
|
|
buf[5] = 0;
|
|
buf[6] = 2;
|
|
buf[7] = 0;
|
|
scsi_sg_copy_from_buffer(sc, buf, 8);
|
|
sc->result = GOOD;
|
|
break;
|
|
|
|
case MODE_SENSE:
|
|
case MODE_SENSE_10:
|
|
/* sd.c uses this to determine whether disk does write-caching. */
|
|
scsi_sg_copy_from_buffer(sc, (char *)empty_zero_page,
|
|
PAGE_SIZE);
|
|
sc->result = GOOD;
|
|
break;
|
|
|
|
case START_STOP:
|
|
printk(KERN_ERR "START_STOP\n");
|
|
break;
|
|
|
|
default:
|
|
panic("simscsi: unknown SCSI command %u\n", sc->cmnd[0]);
|
|
}
|
|
}
|
|
if (sc->result == DID_BAD_TARGET) {
|
|
sc->result |= DRIVER_SENSE << 24;
|
|
sc->sense_buffer[0] = 0x70;
|
|
sc->sense_buffer[2] = 0x00;
|
|
}
|
|
if (atomic_read(&num_reqs) >= SIMSCSI_REQ_QUEUE_LEN) {
|
|
panic("Attempt to queue command while command is pending!!");
|
|
}
|
|
atomic_inc(&num_reqs);
|
|
queue[wr].sc = sc;
|
|
wr = (wr + 1) % SIMSCSI_REQ_QUEUE_LEN;
|
|
|
|
tasklet_schedule(&simscsi_tasklet);
|
|
return 0;
|
|
}
|
|
|
|
static DEF_SCSI_QCMD(simscsi_queuecommand)
|
|
|
|
static int
|
|
simscsi_host_reset (struct scsi_cmnd *sc)
|
|
{
|
|
printk(KERN_ERR "simscsi_host_reset: not implemented\n");
|
|
return 0;
|
|
}
|
|
|
|
static struct scsi_host_template driver_template = {
|
|
.name = "simulated SCSI host adapter",
|
|
.proc_name = "simscsi",
|
|
.queuecommand = simscsi_queuecommand,
|
|
.eh_host_reset_handler = simscsi_host_reset,
|
|
.bios_param = simscsi_biosparam,
|
|
.can_queue = SIMSCSI_REQ_QUEUE_LEN,
|
|
.this_id = -1,
|
|
.sg_tablesize = SG_ALL,
|
|
.max_sectors = 1024,
|
|
.cmd_per_lun = SIMSCSI_REQ_QUEUE_LEN,
|
|
.use_clustering = DISABLE_CLUSTERING,
|
|
};
|
|
|
|
static int __init
|
|
simscsi_init(void)
|
|
{
|
|
int error;
|
|
|
|
host = scsi_host_alloc(&driver_template, 0);
|
|
if (!host)
|
|
return -ENOMEM;
|
|
|
|
error = scsi_add_host(host, NULL);
|
|
if (error)
|
|
goto free_host;
|
|
scsi_scan_host(host);
|
|
return 0;
|
|
|
|
free_host:
|
|
scsi_host_put(host);
|
|
return error;
|
|
}
|
|
device_initcall(simscsi_init);
|