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Diffstat (limited to 'arch/ia64/hp/sim/simscsi.c')
-rw-r--r--arch/ia64/hp/sim/simscsi.c404
1 files changed, 404 insertions, 0 deletions
diff --git a/arch/ia64/hp/sim/simscsi.c b/arch/ia64/hp/sim/simscsi.c
new file mode 100644
index 000000000000..56405dbfd739
--- /dev/null
+++ b/arch/ia64/hp/sim/simscsi.c
@@ -0,0 +1,404 @@
+/*
+ * 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 <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;
+};
+
+extern long ia64_ssc (long arg0, long arg1, long arg2, long arg3, int nr);
+
+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);
+ }
+ 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) != 0) {
+ atomic_dec(&num_reqs);
+ queue[rd].sc = 0;
+ 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_readwrite (struct scsi_cmnd *sc, int mode, unsigned long offset, unsigned long len)
+{
+ struct disk_stat stat;
+ struct disk_req req;
+
+ req.addr = __pa(sc->request_buffer);
+ req.len = len; /* # of bytes to transfer */
+
+ if (sc->request_bufflen < req.len)
+ return;
+
+ stat.fd = desc[sc->device->id];
+ if (DBG)
+ printk("simscsi_%s @ %lx (off %lx)\n",
+ mode == SSC_READ ? "read":"write", req.addr, offset);
+ ia64_ssc(stat.fd, 1, __pa(&req), offset, mode);
+ ia64_ssc(__pa(&stat), 0, 0, 0, SSC_WAIT_COMPLETION);
+
+ if (stat.count == req.len) {
+ sc->result = GOOD;
+ } else {
+ sc->result = DID_ERROR << 16;
+ }
+}
+
+static void
+simscsi_sg_readwrite (struct scsi_cmnd *sc, int mode, unsigned long offset)
+{
+ int list_len = sc->use_sg;
+ struct scatterlist *sl = (struct scatterlist *)sc->buffer;
+ struct disk_stat stat;
+ struct disk_req req;
+
+ stat.fd = desc[sc->device->id];
+
+ while (list_len) {
+ req.addr = __pa(page_address(sl->page) + sl->offset);
+ 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,
+ list_len, 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;
+ sl++;
+ list_len--;
+ }
+ 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;
+ if (sc->use_sg > 0)
+ simscsi_sg_readwrite(sc, mode, offset);
+ else
+ simscsi_readwrite(sc, mode, offset, sc->cmnd[4]*512);
+}
+
+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 4GB.
+ */
+ for (bit = (4UL << 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 = ( (sc->cmnd[2] << 24) | (sc->cmnd[3] << 16)
+ | (sc->cmnd[4] << 8) | (sc->cmnd[5] << 0))*512;
+ if (sc->use_sg > 0)
+ simscsi_sg_readwrite(sc, mode, offset);
+ else
+ simscsi_readwrite(sc, mode, offset, ((sc->cmnd[7] << 8) | sc->cmnd[8])*512);
+}
+
+static int
+simscsi_queuecommand (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;
+#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 (sc->request_bufflen < 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 = sc->request_buffer;
+ 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);
+ 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 || sc->request_bufflen < 8) {
+ break;
+ }
+ buf = sc->request_buffer;
+
+ disk_size = simscsi_get_disk_size(desc[target_id]);
+
+ /* pretend to be a 1GB disk (partition table contains real stuff): */
+ 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;
+ sc->result = GOOD;
+ break;
+
+ case MODE_SENSE:
+ case MODE_SENSE_10:
+ /* sd.c uses this to determine whether disk does write-caching. */
+ memset(sc->request_buffer, 0, 128);
+ 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 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)
+ scsi_scan_host(host);
+ return error;
+}
+
+static void __exit
+simscsi_exit(void)
+{
+ scsi_remove_host(host);
+ scsi_host_put(host);
+}
+
+module_init(simscsi_init);
+module_exit(simscsi_exit);
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