--- /dev/null
+/*
+ * Generic SCSI Device support
+ *
+ * Copyright (c) 2007 Bull S.A.S.
+ * Based on code by Paul Brook
+ * Based on code by Fabrice Bellard
+ *
+ * Written by Laurent Vivier <Laurent.Vivier@bull.net>
+ *
+ * This code is licensed under the LGPL.
+ *
+ */
+
+#include "qemu-common.h"
+#include "qemu/error-report.h"
+#include "hw/scsi/scsi.h"
+#include "sysemu/block-backend.h"
+#include "sysemu/blockdev.h"
+
+#ifdef __linux__
+
+//#define DEBUG_SCSI
+
+#ifdef DEBUG_SCSI
+#define DPRINTF(fmt, ...) \
+do { printf("scsi-generic: " fmt , ## __VA_ARGS__); } while (0)
+#else
+#define DPRINTF(fmt, ...) do {} while(0)
+#endif
+
+#define BADF(fmt, ...) \
+do { fprintf(stderr, "scsi-generic: " fmt , ## __VA_ARGS__); } while (0)
+
+#include <stdio.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <unistd.h>
+#include <scsi/sg.h>
+#include "block/scsi.h"
+
+#define SG_ERR_DRIVER_TIMEOUT 0x06
+#define SG_ERR_DRIVER_SENSE 0x08
+
+#define SG_ERR_DID_OK 0x00
+#define SG_ERR_DID_NO_CONNECT 0x01
+#define SG_ERR_DID_BUS_BUSY 0x02
+#define SG_ERR_DID_TIME_OUT 0x03
+
+#ifndef MAX_UINT
+#define MAX_UINT ((unsigned int)-1)
+#endif
+
+typedef struct SCSIGenericReq {
+ SCSIRequest req;
+ uint8_t *buf;
+ int buflen;
+ int len;
+ sg_io_hdr_t io_header;
+} SCSIGenericReq;
+
+static void scsi_generic_save_request(QEMUFile *f, SCSIRequest *req)
+{
+ SCSIGenericReq *r = DO_UPCAST(SCSIGenericReq, req, req);
+
+ qemu_put_sbe32s(f, &r->buflen);
+ if (r->buflen && r->req.cmd.mode == SCSI_XFER_TO_DEV) {
+ assert(!r->req.sg);
+ qemu_put_buffer(f, r->buf, r->req.cmd.xfer);
+ }
+}
+
+static void scsi_generic_load_request(QEMUFile *f, SCSIRequest *req)
+{
+ SCSIGenericReq *r = DO_UPCAST(SCSIGenericReq, req, req);
+
+ qemu_get_sbe32s(f, &r->buflen);
+ if (r->buflen && r->req.cmd.mode == SCSI_XFER_TO_DEV) {
+ assert(!r->req.sg);
+ qemu_get_buffer(f, r->buf, r->req.cmd.xfer);
+ }
+}
+
+static void scsi_free_request(SCSIRequest *req)
+{
+ SCSIGenericReq *r = DO_UPCAST(SCSIGenericReq, req, req);
+
+ g_free(r->buf);
+}
+
+/* Helper function for command completion. */
+static void scsi_command_complete(void *opaque, int ret)
+{
+ int status;
+ SCSIGenericReq *r = (SCSIGenericReq *)opaque;
+
+ r->req.aiocb = NULL;
+ if (r->req.io_canceled) {
+ scsi_req_cancel_complete(&r->req);
+ goto done;
+ }
+ if (r->io_header.driver_status & SG_ERR_DRIVER_SENSE) {
+ r->req.sense_len = r->io_header.sb_len_wr;
+ }
+
+ if (ret != 0) {
+ switch (ret) {
+ case -EDOM:
+ status = TASK_SET_FULL;
+ break;
+ case -ENOMEM:
+ status = CHECK_CONDITION;
+ scsi_req_build_sense(&r->req, SENSE_CODE(TARGET_FAILURE));
+ break;
+ default:
+ status = CHECK_CONDITION;
+ scsi_req_build_sense(&r->req, SENSE_CODE(IO_ERROR));
+ break;
+ }
+ } else {
+ if (r->io_header.host_status == SG_ERR_DID_NO_CONNECT ||
+ r->io_header.host_status == SG_ERR_DID_BUS_BUSY ||
+ r->io_header.host_status == SG_ERR_DID_TIME_OUT ||
+ (r->io_header.driver_status & SG_ERR_DRIVER_TIMEOUT)) {
+ status = BUSY;
+ BADF("Driver Timeout\n");
+ } else if (r->io_header.host_status) {
+ status = CHECK_CONDITION;
+ scsi_req_build_sense(&r->req, SENSE_CODE(I_T_NEXUS_LOSS));
+ } else if (r->io_header.status) {
+ status = r->io_header.status;
+ } else if (r->io_header.driver_status & SG_ERR_DRIVER_SENSE) {
+ status = CHECK_CONDITION;
+ } else {
+ status = GOOD;
+ }
+ }
+ DPRINTF("Command complete 0x%p tag=0x%x status=%d\n",
+ r, r->req.tag, status);
+
+ scsi_req_complete(&r->req, status);
+done:
+ scsi_req_unref(&r->req);
+}
+
+static int execute_command(BlockBackend *blk,
+ SCSIGenericReq *r, int direction,
+ BlockCompletionFunc *complete)
+{
+ r->io_header.interface_id = 'S';
+ r->io_header.dxfer_direction = direction;
+ r->io_header.dxferp = r->buf;
+ r->io_header.dxfer_len = r->buflen;
+ r->io_header.cmdp = r->req.cmd.buf;
+ r->io_header.cmd_len = r->req.cmd.len;
+ r->io_header.mx_sb_len = sizeof(r->req.sense);
+ r->io_header.sbp = r->req.sense;
+ r->io_header.timeout = MAX_UINT;
+ r->io_header.usr_ptr = r;
+ r->io_header.flags |= SG_FLAG_DIRECT_IO;
+
+ r->req.aiocb = blk_aio_ioctl(blk, SG_IO, &r->io_header, complete, r);
+ if (r->req.aiocb == NULL) {
+ return -EIO;
+ }
+
+ return 0;
+}
+
+static void scsi_read_complete(void * opaque, int ret)
+{
+ SCSIGenericReq *r = (SCSIGenericReq *)opaque;
+ SCSIDevice *s = r->req.dev;
+ int len;
+
+ r->req.aiocb = NULL;
+ if (ret || r->req.io_canceled) {
+ scsi_command_complete(r, ret);
+ return;
+ }
+ len = r->io_header.dxfer_len - r->io_header.resid;
+ DPRINTF("Data ready tag=0x%x len=%d\n", r->req.tag, len);
+
+ r->len = -1;
+ if (len == 0) {
+ scsi_command_complete(r, 0);
+ } else {
+ /* Snoop READ CAPACITY output to set the blocksize. */
+ if (r->req.cmd.buf[0] == READ_CAPACITY_10 &&
+ (ldl_be_p(&r->buf[0]) != 0xffffffffU || s->max_lba == 0)) {
+ s->blocksize = ldl_be_p(&r->buf[4]);
+ s->max_lba = ldl_be_p(&r->buf[0]) & 0xffffffffULL;
+ } else if (r->req.cmd.buf[0] == SERVICE_ACTION_IN_16 &&
+ (r->req.cmd.buf[1] & 31) == SAI_READ_CAPACITY_16) {
+ s->blocksize = ldl_be_p(&r->buf[8]);
+ s->max_lba = ldq_be_p(&r->buf[0]);
+ }
+ blk_set_guest_block_size(s->conf.blk, s->blocksize);
+
+ scsi_req_data(&r->req, len);
+ scsi_req_unref(&r->req);
+ }
+}
+
+/* Read more data from scsi device into buffer. */
+static void scsi_read_data(SCSIRequest *req)
+{
+ SCSIGenericReq *r = DO_UPCAST(SCSIGenericReq, req, req);
+ SCSIDevice *s = r->req.dev;
+ int ret;
+
+ DPRINTF("scsi_read_data 0x%x\n", req->tag);
+
+ /* The request is used as the AIO opaque value, so add a ref. */
+ scsi_req_ref(&r->req);
+ if (r->len == -1) {
+ scsi_command_complete(r, 0);
+ return;
+ }
+
+ ret = execute_command(s->conf.blk, r, SG_DXFER_FROM_DEV,
+ scsi_read_complete);
+ if (ret < 0) {
+ scsi_command_complete(r, ret);
+ }
+}
+
+static void scsi_write_complete(void * opaque, int ret)
+{
+ SCSIGenericReq *r = (SCSIGenericReq *)opaque;
+ SCSIDevice *s = r->req.dev;
+
+ DPRINTF("scsi_write_complete() ret = %d\n", ret);
+ r->req.aiocb = NULL;
+ if (ret || r->req.io_canceled) {
+ scsi_command_complete(r, ret);
+ return;
+ }
+
+ if (r->req.cmd.buf[0] == MODE_SELECT && r->req.cmd.buf[4] == 12 &&
+ s->type == TYPE_TAPE) {
+ s->blocksize = (r->buf[9] << 16) | (r->buf[10] << 8) | r->buf[11];
+ DPRINTF("block size %d\n", s->blocksize);
+ }
+
+ scsi_command_complete(r, ret);
+}
+
+/* Write data to a scsi device. Returns nonzero on failure.
+ The transfer may complete asynchronously. */
+static void scsi_write_data(SCSIRequest *req)
+{
+ SCSIGenericReq *r = DO_UPCAST(SCSIGenericReq, req, req);
+ SCSIDevice *s = r->req.dev;
+ int ret;
+
+ DPRINTF("scsi_write_data 0x%x\n", req->tag);
+ if (r->len == 0) {
+ r->len = r->buflen;
+ scsi_req_data(&r->req, r->len);
+ return;
+ }
+
+ /* The request is used as the AIO opaque value, so add a ref. */
+ scsi_req_ref(&r->req);
+ ret = execute_command(s->conf.blk, r, SG_DXFER_TO_DEV, scsi_write_complete);
+ if (ret < 0) {
+ scsi_command_complete(r, ret);
+ }
+}
+
+/* Return a pointer to the data buffer. */
+static uint8_t *scsi_get_buf(SCSIRequest *req)
+{
+ SCSIGenericReq *r = DO_UPCAST(SCSIGenericReq, req, req);
+
+ return r->buf;
+}
+
+/* Execute a scsi command. Returns the length of the data expected by the
+ command. This will be Positive for data transfers from the device
+ (eg. disk reads), negative for transfers to the device (eg. disk writes),
+ and zero if the command does not transfer any data. */
+
+static int32_t scsi_send_command(SCSIRequest *req, uint8_t *cmd)
+{
+ SCSIGenericReq *r = DO_UPCAST(SCSIGenericReq, req, req);
+ SCSIDevice *s = r->req.dev;
+ int ret;
+
+#ifdef DEBUG_SCSI
+ {
+ int i;
+ for (i = 1; i < r->req.cmd.len; i++) {
+ printf(" 0x%02x", cmd[i]);
+ }
+ printf("\n");
+ }
+#endif
+
+ if (r->req.cmd.xfer == 0) {
+ g_free(r->buf);
+ r->buflen = 0;
+ r->buf = NULL;
+ /* The request is used as the AIO opaque value, so add a ref. */
+ scsi_req_ref(&r->req);
+ ret = execute_command(s->conf.blk, r, SG_DXFER_NONE,
+ scsi_command_complete);
+ if (ret < 0) {
+ scsi_command_complete(r, ret);
+ return 0;
+ }
+ return 0;
+ }
+
+ if (r->buflen != r->req.cmd.xfer) {
+ g_free(r->buf);
+ r->buf = g_malloc(r->req.cmd.xfer);
+ r->buflen = r->req.cmd.xfer;
+ }
+
+ memset(r->buf, 0, r->buflen);
+ r->len = r->req.cmd.xfer;
+ if (r->req.cmd.mode == SCSI_XFER_TO_DEV) {
+ r->len = 0;
+ return -r->req.cmd.xfer;
+ } else {
+ return r->req.cmd.xfer;
+ }
+}
+
+static int get_stream_blocksize(BlockBackend *blk)
+{
+ uint8_t cmd[6];
+ uint8_t buf[12];
+ uint8_t sensebuf[8];
+ sg_io_hdr_t io_header;
+ int ret;
+
+ memset(cmd, 0, sizeof(cmd));
+ memset(buf, 0, sizeof(buf));
+ cmd[0] = MODE_SENSE;
+ cmd[4] = sizeof(buf);
+
+ memset(&io_header, 0, sizeof(io_header));
+ io_header.interface_id = 'S';
+ io_header.dxfer_direction = SG_DXFER_FROM_DEV;
+ io_header.dxfer_len = sizeof(buf);
+ io_header.dxferp = buf;
+ io_header.cmdp = cmd;
+ io_header.cmd_len = sizeof(cmd);
+ io_header.mx_sb_len = sizeof(sensebuf);
+ io_header.sbp = sensebuf;
+ io_header.timeout = 6000; /* XXX */
+
+ ret = blk_ioctl(blk, SG_IO, &io_header);
+ if (ret < 0 || io_header.driver_status || io_header.host_status) {
+ return -1;
+ }
+ return (buf[9] << 16) | (buf[10] << 8) | buf[11];
+}
+
+static void scsi_generic_reset(DeviceState *dev)
+{
+ SCSIDevice *s = SCSI_DEVICE(dev);
+
+ scsi_device_purge_requests(s, SENSE_CODE(RESET));
+}
+
+static void scsi_generic_realize(SCSIDevice *s, Error **errp)
+{
+ int rc;
+ int sg_version;
+ struct sg_scsi_id scsiid;
+
+ if (!s->conf.blk) {
+ error_setg(errp, "drive property not set");
+ return;
+ }
+
+ if (blk_get_on_error(s->conf.blk, 0) != BLOCKDEV_ON_ERROR_ENOSPC) {
+ error_setg(errp, "Device doesn't support drive option werror");
+ return;
+ }
+ if (blk_get_on_error(s->conf.blk, 1) != BLOCKDEV_ON_ERROR_REPORT) {
+ error_setg(errp, "Device doesn't support drive option rerror");
+ return;
+ }
+
+ /* check we are using a driver managing SG_IO (version 3 and after */
+ rc = blk_ioctl(s->conf.blk, SG_GET_VERSION_NUM, &sg_version);
+ if (rc < 0) {
+ error_setg(errp, "cannot get SG_IO version number: %s. "
+ "Is this a SCSI device?",
+ strerror(-rc));
+ return;
+ }
+ if (sg_version < 30000) {
+ error_setg(errp, "scsi generic interface too old");
+ return;
+ }
+
+ /* get LUN of the /dev/sg? */
+ if (blk_ioctl(s->conf.blk, SG_GET_SCSI_ID, &scsiid)) {
+ error_setg(errp, "SG_GET_SCSI_ID ioctl failed");
+ return;
+ }
+
+ /* define device state */
+ s->type = scsiid.scsi_type;
+ DPRINTF("device type %d\n", s->type);
+
+ switch (s->type) {
+ case TYPE_TAPE:
+ s->blocksize = get_stream_blocksize(s->conf.blk);
+ if (s->blocksize == -1) {
+ s->blocksize = 0;
+ }
+ break;
+
+ /* Make a guess for block devices, we'll fix it when the guest sends.
+ * READ CAPACITY. If they don't, they likely would assume these sizes
+ * anyway. (TODO: they could also send MODE SENSE).
+ */
+ case TYPE_ROM:
+ case TYPE_WORM:
+ s->blocksize = 2048;
+ break;
+ default:
+ s->blocksize = 512;
+ break;
+ }
+
+ DPRINTF("block size %d\n", s->blocksize);
+}
+
+const SCSIReqOps scsi_generic_req_ops = {
+ .size = sizeof(SCSIGenericReq),
+ .free_req = scsi_free_request,
+ .send_command = scsi_send_command,
+ .read_data = scsi_read_data,
+ .write_data = scsi_write_data,
+ .get_buf = scsi_get_buf,
+ .load_request = scsi_generic_load_request,
+ .save_request = scsi_generic_save_request,
+};
+
+static SCSIRequest *scsi_new_request(SCSIDevice *d, uint32_t tag, uint32_t lun,
+ uint8_t *buf, void *hba_private)
+{
+ SCSIRequest *req;
+
+ req = scsi_req_alloc(&scsi_generic_req_ops, d, tag, lun, hba_private);
+ return req;
+}
+
+static Property scsi_generic_properties[] = {
+ DEFINE_PROP_DRIVE("drive", SCSIDevice, conf.blk),
+ DEFINE_PROP_END_OF_LIST(),
+};
+
+static int scsi_generic_parse_cdb(SCSIDevice *dev, SCSICommand *cmd,
+ uint8_t *buf, void *hba_private)
+{
+ return scsi_bus_parse_cdb(dev, cmd, buf, hba_private);
+}
+
+static void scsi_generic_class_initfn(ObjectClass *klass, void *data)
+{
+ DeviceClass *dc = DEVICE_CLASS(klass);
+ SCSIDeviceClass *sc = SCSI_DEVICE_CLASS(klass);
+
+ sc->realize = scsi_generic_realize;
+ sc->alloc_req = scsi_new_request;
+ sc->parse_cdb = scsi_generic_parse_cdb;
+ dc->fw_name = "disk";
+ dc->desc = "pass through generic scsi device (/dev/sg*)";
+ dc->reset = scsi_generic_reset;
+ dc->props = scsi_generic_properties;
+ dc->vmsd = &vmstate_scsi_device;
+}
+
+static const TypeInfo scsi_generic_info = {
+ .name = "scsi-generic",
+ .parent = TYPE_SCSI_DEVICE,
+ .instance_size = sizeof(SCSIDevice),
+ .class_init = scsi_generic_class_initfn,
+};
+
+static void scsi_generic_register_types(void)
+{
+ type_register_static(&scsi_generic_info);
+}
+
+type_init(scsi_generic_register_types)
+
+#endif /* __linux__ */
Code Review / kvmfornfv.git / blobdiff