scsi-disk.c

xen 3.2.2 源码

        lba = buf[3] | (buf[2] << 8) | ((buf[1] & 0x1f) << 16);
        len = buf[4];
        cmdlen = 6;
        break;
    case 1:
    case 2:
        lba = buf[5] | (buf[4] << 8) | (buf[3] << 16) | (buf[2] << 24);
        len = buf[8] | (buf[7] << 8);
        cmdlen = 10;
        break;
    case 4:
        lba = buf[5] | (buf[4] << 8) | (buf[3] << 16) | (buf[2] << 24);
        len = buf[13] | (buf[12] << 8) | (buf[11] << 16) | (buf[10] << 24);
        cmdlen = 16;
        break;
    case 5:
        lba = buf[5] | (buf[4] << 8) | (buf[3] << 16) | (buf[2] << 24);
        len = buf[9] | (buf[8] << 8) | (buf[7] << 16) | (buf[6] << 24);
        cmdlen = 12;
        break;
    default:
        BADF("Unsupported command length, command %x\n", command);
        goto fail;
    }
#ifdef DEBUG_SCSI
    {
        int i;
        for (i = 1; i < cmdlen; i++) {
            printf(" 0x%02x", buf[i]);
        }
        printf("\n");
    }
#endif
    if (lun || buf[1] >> 5) {
        /* Only LUN 0 supported.  */
        DPRINTF("Unimplemented LUN %d\n", lun ? lun : buf[1] >> 5);
        goto fail;
    }
    switch (command) {
    case 0x0:
	DPRINTF("Test Unit Ready\n");
	break;
    case 0x03:
        DPRINTF("Request Sense (len %d)\n", len);
        if (len < 4)
            goto fail;
        memset(buf, 0, 4);
        outbuf[0] = 0xf0;
        outbuf[1] = 0;
        outbuf[2] = s->sense;
        r->buf_len = 4;
        break;
    case 0x12:
        DPRINTF("Inquiry (len %d)\n", len);
        if (len < 36) {
            BADF("Inquiry buffer too small (%d)\n", len);
        }
	memset(outbuf, 0, 36);
	if (bdrv_get_type_hint(s->bdrv) == BDRV_TYPE_CDROM) {
	    outbuf[0] = 5;
            outbuf[1] = 0x80;
	    memcpy(&outbuf[16], "QEMU CD-ROM    ", 16);
	} else {
	    outbuf[0] = 0;
	    memcpy(&outbuf[16], "QEMU HARDDISK  ", 16);
	}
	memcpy(&outbuf[8], "QEMU   ", 8);
        memcpy(&outbuf[32], QEMU_VERSION, 4);
        /* Identify device as SCSI-3 rev 1.
           Some later commands are also implemented. */
	outbuf[2] = 3;
	outbuf[3] = 2; /* Format 2 */
	outbuf[4] = 32;
        /* Sync data transfer and TCQ.  */
        outbuf[7] = 0x10 | (s->tcq ? 0x02 : 0);
	r->buf_len = 36;
	break;
    case 0x16:
        DPRINTF("Reserve(6)\n");
        if (buf[1] & 1)
            goto fail;
        break;
    case 0x17:
        DPRINTF("Release(6)\n");
        if (buf[1] & 1)
            goto fail;
        break;
    case 0x1a:
    case 0x5a:
        {
            uint8_t *p;
            int page;

            page = buf[2] & 0x3f;
            DPRINTF("Mode Sense (page %d, len %d)\n", page, len);
            p = outbuf;
            memset(p, 0, 4);
            outbuf[1] = 0; /* Default media type.  */
            outbuf[3] = 0; /* Block descriptor length.  */
            if (bdrv_get_type_hint(s->bdrv) == BDRV_TYPE_CDROM) {
                outbuf[2] = 0x80; /* Readonly.  */
            }
            p += 4;
            if ((page == 8 || page == 0x3f)) {
                /* Caching page.  */
                p[0] = 8;
                p[1] = 0x12;
                p[2] = 4; /* WCE */
                p += 19;
            }
            if ((page == 0x3f || page == 0x2a)
                    && (bdrv_get_type_hint(s->bdrv) == BDRV_TYPE_CDROM)) {
                /* CD Capabilities and Mechanical Status page. */
                p[0] = 0x2a;
                p[1] = 0x14;
                p[2] = 3; // CD-R & CD-RW read
                p[3] = 0; // Writing not supported
                p[4] = 0x7f; /* Audio, composite, digital out,
                                         mode 2 form 1&2, multi session */
                p[5] = 0xff; /* CD DA, DA accurate, RW supported,
                                         RW corrected, C2 errors, ISRC,
                                         UPC, Bar code */
                p[6] = 0x2d | (bdrv_is_locked(s->bdrv)? 2 : 0);
                /* Locking supported, jumper present, eject, tray */
                p[7] = 0; /* no volume & mute control, no
                                      changer */
                p[8] = (50 * 176) >> 8; // 50x read speed
                p[9] = (50 * 176) & 0xff;
                p[10] = 0 >> 8; // No volume
                p[11] = 0 & 0xff;
                p[12] = 2048 >> 8; // 2M buffer
                p[13] = 2048 & 0xff;
                p[14] = (16 * 176) >> 8; // 16x read speed current
                p[15] = (16 * 176) & 0xff;
                p[18] = (16 * 176) >> 8; // 16x write speed
                p[19] = (16 * 176) & 0xff;
                p[20] = (16 * 176) >> 8; // 16x write speed current
                p[21] = (16 * 176) & 0xff;
                p += 21;
            }
            r->buf_len = p - outbuf;
            outbuf[0] = r->buf_len - 4;
            if (r->buf_len > len)
                r->buf_len = len;
        }
        break;
    case 0x1b:
        DPRINTF("Start Stop Unit\n");
	break;
    case 0x1e:
        DPRINTF("Prevent Allow Medium Removal (prevent = %d)\n", buf[4] & 3);
        bdrv_set_locked(s->bdrv, buf[4] & 1);
	break;
    case 0x25:
	DPRINTF("Read Capacity\n");
        /* The normal LEN field for this command is zero.  */
	memset(outbuf, 0, 8);
	bdrv_get_geometry(s->bdrv, &nb_sectors);
        /* Returned value is the address of the last sector.  */
        if (nb_sectors) {
            nb_sectors--;
            outbuf[0] = (nb_sectors >> 24) & 0xff;
            outbuf[1] = (nb_sectors >> 16) & 0xff;
            outbuf[2] = (nb_sectors >> 8) & 0xff;
            outbuf[3] = nb_sectors & 0xff;
            outbuf[4] = 0;
            outbuf[5] = 0;
            outbuf[6] = s->cluster_size * 2;
            outbuf[7] = 0;
            r->buf_len = 8;
        } else {
            scsi_command_complete(r, SENSE_NOT_READY);
            return 0;
        }
	break;
    case 0x08:
    case 0x28:
        DPRINTF("Read (sector %d, count %d)\n", lba, len);
        r->sector = lba * s->cluster_size;
        r->sector_count = len * s->cluster_size;
        break;
    case 0x0a:
    case 0x2a:
        DPRINTF("Write (sector %d, count %d)\n", lba, len);
        r->sector = lba * s->cluster_size;
        r->sector_count = len * s->cluster_size;
        is_write = 1;
        break;
    case 0x35:
        DPRINTF("Syncronise cache (sector %d, count %d)\n", lba, len);
        bdrv_flush(s->bdrv);
        break;
    case 0x43:
        {
            int start_track, format, msf, toclen;

            msf = buf[1] & 2;
            format = buf[2] & 0xf;
            start_track = buf[6];
            bdrv_get_geometry(s->bdrv, &nb_sectors);
            DPRINTF("Read TOC (track %d format %d msf %d)\n", start_track, format, msf >> 1);
            switch(format) {
            case 0:
                toclen = cdrom_read_toc(nb_sectors, outbuf, msf, start_track);
                break;
            case 1:
                /* multi session : only a single session defined */
                toclen = 12;
                memset(outbuf, 0, 12);
                outbuf[1] = 0x0a;
                outbuf[2] = 0x01;
                outbuf[3] = 0x01;
                break;
            case 2:
                toclen = cdrom_read_toc_raw(nb_sectors, outbuf, msf, start_track);
                break;
            default:
                goto error_cmd;
            }
            if (toclen > 0) {
                if (len > toclen)
                  len = toclen;
                r->buf_len = len;
                break;
            }
        error_cmd:
            DPRINTF("Read TOC error\n");
            goto fail;
        }
    case 0x46:
        DPRINTF("Get Configuration (rt %d, maxlen %d)\n", buf[1] & 3, len);
        memset(outbuf, 0, 8);
        /* ??? This shoud probably return much more information.  For now
           just return the basic header indicating the CD-ROM profile.  */
        outbuf[7] = 8; // CD-ROM
        r->buf_len = 8;
        break;
    case 0x56:
        DPRINTF("Reserve(10)\n");
        if (buf[1] & 3)
            goto fail;
        break;
    case 0x57:
        DPRINTF("Release(10)\n");
        if (buf[1] & 3)
            goto fail;
        break;
    case 0xa0:
        DPRINTF("Report LUNs (len %d)\n", len);
        if (len < 16)
            goto fail;
        memset(outbuf, 0, 16);
        outbuf[3] = 8;
        r->buf_len = 16;
        break;
    default:
	DPRINTF("Unknown SCSI command (%2.2x)\n", buf[0]);
    fail:
        scsi_command_complete(r, SENSE_ILLEGAL_REQUEST);
	return 0;
    }
    if (r->sector_count == 0 && r->buf_len == 0) {
        scsi_command_complete(r, SENSE_NO_SENSE);
    }
    len = r->sector_count * 512 + r->buf_len;
    if (is_write) {
        return -len;
    } else {
        if (!r->sector_count)
            r->sector_count = -1;
        return len;
    }
}

void scsi_disk_destroy(SCSIDevice *s)
{
    qemu_free(s);
}

SCSIDevice *scsi_disk_init(BlockDriverState *bdrv,
                           int tcq,
                           scsi_completionfn completion,
                           void *opaque)
{
    SCSIDevice *s;

    s = (SCSIDevice *)qemu_mallocz(sizeof(SCSIDevice));
    s->bdrv = bdrv;
    s->tcq = tcq;
    s->completion = completion;
    s->opaque = opaque;
    if (bdrv_get_type_hint(s->bdrv) == BDRV_TYPE_CDROM) {
        s->cluster_size = 4;
    } else {
        s->cluster_size = 1;
    }

    return s;
}