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author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-17 00:20:36 +0200 |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-17 00:20:36 +0200 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /arch/ia64/hp/sim/simscsi.c | |
download | linux-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.xz linux-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.zip |
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'arch/ia64/hp/sim/simscsi.c')
-rw-r--r-- | arch/ia64/hp/sim/simscsi.c | 404 |
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); |