hw: move SCSI controllers to hw/scsi/, configure via default-configs/

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

1 files changed, 982 insertions, 0 deletions

diff --git a/hw/scsi/spapr_vscsi.c b/hw/scsi/spapr_vscsi.c
new file mode 100644
index 0000000000..e92b09a522
--- /dev/null
+++ b/hw/scsi/spapr_vscsi.c
@@ -0,0 +1,982 @@
+/*
+ * QEMU PowerPC pSeries Logical Partition (aka sPAPR) hardware System Emulator
+ *
+ * PAPR Virtual SCSI, aka ibmvscsi
+ *
+ * Copyright (c) 2010,2011 Benjamin Herrenschmidt, IBM Corporation.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ *
+ * TODO:
+ *
+ *  - Cleanups :-)
+ *  - Sort out better how to assign devices to VSCSI instances
+ *  - Fix residual counts
+ *  - Add indirect descriptors support
+ *  - Maybe do autosense (PAPR seems to mandate it, linux doesn't care)
+ */
+#include "hw/hw.h"
+#include "hw/scsi/scsi.h"
+#include "block/scsi.h"
+#include "hw/srp.h"
+#include "hw/qdev.h"
+#include "hw/ppc/spapr.h"
+#include "hw/ppc/spapr_vio.h"
+#include "hw/ppc-viosrp.h"
+
+#include <libfdt.h>
+
+/*#define DEBUG_VSCSI*/
+
+#ifdef DEBUG_VSCSI
+#define dprintf(fmt, ...) \
+    do { fprintf(stderr, fmt, ## __VA_ARGS__); } while (0)
+#else
+#define dprintf(fmt, ...) \
+    do { } while (0)
+#endif
+
+/*
+ * Virtual SCSI device
+ */
+
+/* Random numbers */
+#define VSCSI_MAX_SECTORS       4096
+#define VSCSI_REQ_LIMIT         24
+
+#define SCSI_SENSE_BUF_SIZE     96
+#define SRP_RSP_SENSE_DATA_LEN  18
+
+typedef union vscsi_crq {
+    struct viosrp_crq s;
+    uint8_t raw[16];
+} vscsi_crq;
+
+typedef struct vscsi_req {
+    vscsi_crq               crq;
+    union viosrp_iu         iu;
+
+    /* SCSI request tracking */
+    SCSIRequest             *sreq;
+    uint32_t                qtag; /* qemu tag != srp tag */
+    int                     lun;
+    int                     active;
+    long                    data_len;
+    int                     writing;
+    int                     senselen;
+    uint8_t                 sense[SCSI_SENSE_BUF_SIZE];
+
+    /* RDMA related bits */
+    uint8_t                 dma_fmt;
+    struct srp_direct_buf   ext_desc;
+    struct srp_direct_buf   *cur_desc;
+    struct srp_indirect_buf *ind_desc;
+    int                     local_desc;
+    int                     total_desc;
+} vscsi_req;
+
+
+typedef struct {
+    VIOsPAPRDevice vdev;
+    SCSIBus bus;
+    vscsi_req reqs[VSCSI_REQ_LIMIT];
+} VSCSIState;
+
+static struct vscsi_req *vscsi_get_req(VSCSIState *s)
+{
+    vscsi_req *req;
+    int i;
+
+    for (i = 0; i < VSCSI_REQ_LIMIT; i++) {
+        req = &s->reqs[i];
+        if (!req->active) {
+            memset(req, 0, sizeof(*req));
+            req->qtag = i;
+            req->active = 1;
+            return req;
+        }
+    }
+    return NULL;
+}
+
+static void vscsi_put_req(vscsi_req *req)
+{
+    if (req->sreq != NULL) {
+        scsi_req_unref(req->sreq);
+    }
+    req->sreq = NULL;
+    req->active = 0;
+}
+
+static SCSIDevice *vscsi_device_find(SCSIBus *bus, uint64_t srp_lun, int *lun)
+{
+    int channel = 0, id = 0;
+
+retry:
+    switch (srp_lun >> 62) {
+    case 0:
+        if ((srp_lun >> 56) != 0) {
+            channel = (srp_lun >> 56) & 0x3f;
+            id = (srp_lun >> 48) & 0xff;
+            srp_lun <<= 16;
+            goto retry;
+        }
+        *lun = (srp_lun >> 48) & 0xff;
+        break;
+
+    case 1:
+        *lun = (srp_lun >> 48) & 0x3fff;
+        break;
+    case 2:
+        channel = (srp_lun >> 53) & 0x7;
+        id = (srp_lun >> 56) & 0x3f;
+        *lun = (srp_lun >> 48) & 0x1f;
+        break;
+    case 3:
+        *lun = -1;
+        return NULL;
+    default:
+        abort();
+    }
+
+    return scsi_device_find(bus, channel, id, *lun);
+}
+
+static int vscsi_send_iu(VSCSIState *s, vscsi_req *req,
+                         uint64_t length, uint8_t format)
+{
+    long rc, rc1;
+
+    /* First copy the SRP */
+    rc = spapr_vio_dma_write(&s->vdev, req->crq.s.IU_data_ptr,
+                             &req->iu, length);
+    if (rc) {
+        fprintf(stderr, "vscsi_send_iu: DMA write failure !\n");
+    }
+
+    req->crq.s.valid = 0x80;
+    req->crq.s.format = format;
+    req->crq.s.reserved = 0x00;
+    req->crq.s.timeout = cpu_to_be16(0x0000);
+    req->crq.s.IU_length = cpu_to_be16(length);
+    req->crq.s.IU_data_ptr = req->iu.srp.rsp.tag; /* right byte order */
+
+    if (rc == 0) {
+        req->crq.s.status = 0x99; /* Just needs to be non-zero */
+    } else {
+        req->crq.s.status = 0x00;
+    }
+
+    rc1 = spapr_vio_send_crq(&s->vdev, req->crq.raw);
+    if (rc1) {
+        fprintf(stderr, "vscsi_send_iu: Error sending response\n");
+        return rc1;
+    }
+
+    return rc;
+}
+
+static void vscsi_makeup_sense(VSCSIState *s, vscsi_req *req,
+                               uint8_t key, uint8_t asc, uint8_t ascq)
+{
+    req->senselen = SRP_RSP_SENSE_DATA_LEN;
+
+    /* Valid bit and 'current errors' */
+    req->sense[0] = (0x1 << 7 | 0x70);
+    /* Sense key */
+    req->sense[2] = key;
+    /* Additional sense length */
+    req->sense[7] = 0xa; /* 10 bytes */
+    /* Additional sense code */
+    req->sense[12] = asc;
+    req->sense[13] = ascq;
+}
+
+static int vscsi_send_rsp(VSCSIState *s, vscsi_req *req,
+                          uint8_t status, int32_t res_in, int32_t res_out)
+{
+    union viosrp_iu *iu = &req->iu;
+    uint64_t tag = iu->srp.rsp.tag;
+    int total_len = sizeof(iu->srp.rsp);
+
+    dprintf("VSCSI: Sending resp status: 0x%x, "
+            "res_in: %d, res_out: %d\n", status, res_in, res_out);
+
+    memset(iu, 0, sizeof(struct srp_rsp));
+    iu->srp.rsp.opcode = SRP_RSP;
+    iu->srp.rsp.req_lim_delta = cpu_to_be32(1);
+    iu->srp.rsp.tag = tag;
+
+    /* Handle residuals */
+    if (res_in < 0) {
+        iu->srp.rsp.flags |= SRP_RSP_FLAG_DIUNDER;
+        res_in = -res_in;
+    } else if (res_in) {
+        iu->srp.rsp.flags |= SRP_RSP_FLAG_DIOVER;
+    }
+    if (res_out < 0) {
+        iu->srp.rsp.flags |= SRP_RSP_FLAG_DOUNDER;
+        res_out = -res_out;
+    } else if (res_out) {
+        iu->srp.rsp.flags |= SRP_RSP_FLAG_DOOVER;
+    }
+    iu->srp.rsp.data_in_res_cnt = cpu_to_be32(res_in);
+    iu->srp.rsp.data_out_res_cnt = cpu_to_be32(res_out);
+
+    /* We don't do response data */
+    /* iu->srp.rsp.flags &= ~SRP_RSP_FLAG_RSPVALID; */
+    iu->srp.rsp.resp_data_len = cpu_to_be32(0);
+
+    /* Handle success vs. failure */
+    iu->srp.rsp.status = status;
+    if (status) {
+        iu->srp.rsp.sol_not = (iu->srp.cmd.sol_not & 0x04) >> 2;
+        if (req->senselen) {
+            req->iu.srp.rsp.flags |= SRP_RSP_FLAG_SNSVALID;
+            req->iu.srp.rsp.sense_data_len = cpu_to_be32(req->senselen);
+            memcpy(req->iu.srp.rsp.data, req->sense, req->senselen);
+            total_len += req->senselen;
+        }
+    } else {
+        iu->srp.rsp.sol_not = (iu->srp.cmd.sol_not & 0x02) >> 1;
+    }
+
+    vscsi_send_iu(s, req, total_len, VIOSRP_SRP_FORMAT);
+    return 0;
+}
+
+static inline void vscsi_swap_desc(struct srp_direct_buf *desc)
+{
+    desc->va = be64_to_cpu(desc->va);
+    desc->len = be32_to_cpu(desc->len);
+}
+
+static int vscsi_srp_direct_data(VSCSIState *s, vscsi_req *req,
+                                 uint8_t *buf, uint32_t len)
+{
+    struct srp_direct_buf *md = req->cur_desc;
+    uint32_t llen;
+    int rc = 0;
+
+    dprintf("VSCSI: direct segment 0x%x bytes, va=0x%llx desc len=0x%x\n",
+            len, (unsigned long long)md->va, md->len);
+
+    llen = MIN(len, md->len);
+    if (llen) {
+        if (req->writing) { /* writing = to device = reading from memory */
+            rc = spapr_vio_dma_read(&s->vdev, md->va, buf, llen);
+        } else {
+            rc = spapr_vio_dma_write(&s->vdev, md->va, buf, llen);
+        }
+    }
+    md->len -= llen;
+    md->va += llen;
+
+    if (rc) {
+        return -1;
+    }
+    return llen;
+}
+
+static int vscsi_srp_indirect_data(VSCSIState *s, vscsi_req *req,
+                                   uint8_t *buf, uint32_t len)
+{
+    struct srp_direct_buf *td = &req->ind_desc->table_desc;
+    struct srp_direct_buf *md = req->cur_desc;
+    int rc = 0;
+    uint32_t llen, total = 0;
+
+    dprintf("VSCSI: indirect segment 0x%x bytes, td va=0x%llx len=0x%x\n",
+            len, (unsigned long long)td->va, td->len);
+
+    /* While we have data ... */
+    while (len) {
+        /* If we have a descriptor but it's empty, go fetch a new one */
+        if (md && md->len == 0) {
+            /* More local available, use one */
+            if (req->local_desc) {
+                md = ++req->cur_desc;
+                --req->local_desc;
+                --req->total_desc;
+                td->va += sizeof(struct srp_direct_buf);
+            } else {
+                md = req->cur_desc = NULL;
+            }
+        }
+        /* No descriptor at hand, fetch one */
+        if (!md) {
+            if (!req->total_desc) {
+                dprintf("VSCSI:   Out of descriptors !\n");
+                break;
+            }
+            md = req->cur_desc = &req->ext_desc;
+            dprintf("VSCSI:   Reading desc from 0x%llx\n",
+                    (unsigned long long)td->va);
+            rc = spapr_vio_dma_read(&s->vdev, td->va, md,
+                                    sizeof(struct srp_direct_buf));
+            if (rc) {
+                dprintf("VSCSI: spapr_vio_dma_read -> %d reading ext_desc\n",
+                        rc);
+                break;
+            }
+            vscsi_swap_desc(md);
+            td->va += sizeof(struct srp_direct_buf);
+            --req->total_desc;
+        }
+        dprintf("VSCSI:   [desc va=0x%llx,len=0x%x] remaining=0x%x\n",
+                (unsigned long long)md->va, md->len, len);
+
+        /* Perform transfer */
+        llen = MIN(len, md->len);
+        if (req->writing) { /* writing = to device = reading from memory */
+            rc = spapr_vio_dma_read(&s->vdev, md->va, buf, llen);
+        } else {
+            rc = spapr_vio_dma_write(&s->vdev, md->va, buf, llen);
+        }
+        if (rc) {
+            dprintf("VSCSI: spapr_vio_dma_r/w(%d) -> %d\n", req->writing, rc);
+            break;
+        }
+        dprintf("VSCSI:     data: %02x %02x %02x %02x...\n",
+                buf[0], buf[1], buf[2], buf[3]);
+
+        len -= llen;
+        buf += llen;
+        total += llen;
+        md->va += llen;
+        md->len -= llen;
+    }
+    return rc ? -1 : total;
+}
+
+static int vscsi_srp_transfer_data(VSCSIState *s, vscsi_req *req,
+                                   int writing, uint8_t *buf, uint32_t len)
+{
+    int err = 0;
+
+    switch (req->dma_fmt) {
+    case SRP_NO_DATA_DESC:
+        dprintf("VSCSI: no data desc transfer, skipping 0x%x bytes\n", len);
+        break;
+    case SRP_DATA_DESC_DIRECT:
+        err = vscsi_srp_direct_data(s, req, buf, len);
+        break;
+    case SRP_DATA_DESC_INDIRECT:
+        err = vscsi_srp_indirect_data(s, req, buf, len);
+        break;
+    }
+    return err;
+}
+
+/* Bits from linux srp */
+static int data_out_desc_size(struct srp_cmd *cmd)
+{
+    int size = 0;
+    uint8_t fmt = cmd->buf_fmt >> 4;
+
+    switch (fmt) {
+    case SRP_NO_DATA_DESC:
+        break;
+    case SRP_DATA_DESC_DIRECT:
+        size = sizeof(struct srp_direct_buf);
+        break;
+    case SRP_DATA_DESC_INDIRECT:
+        size = sizeof(struct srp_indirect_buf) +
+            sizeof(struct srp_direct_buf)*cmd->data_out_desc_cnt;
+        break;
+    default:
+        break;
+    }
+    return size;
+}
+
+static int vscsi_preprocess_desc(vscsi_req *req)
+{
+    struct srp_cmd *cmd = &req->iu.srp.cmd;
+    int offset, i;
+
+    offset = cmd->add_cdb_len & ~3;
+
+    if (req->writing) {
+        req->dma_fmt = cmd->buf_fmt >> 4;
+    } else {
+        offset += data_out_desc_size(cmd);
+        req->dma_fmt = cmd->buf_fmt & ((1U << 4) - 1);
+    }
+
+    switch (req->dma_fmt) {
+    case SRP_NO_DATA_DESC:
+        break;
+    case SRP_DATA_DESC_DIRECT:
+        req->cur_desc = (struct srp_direct_buf *)(cmd->add_data + offset);
+        req->total_desc = req->local_desc = 1;
+        vscsi_swap_desc(req->cur_desc);
+        dprintf("VSCSI: using direct RDMA %s, 0x%x bytes MD: 0x%llx\n",
+                req->writing ? "write" : "read",
+                req->cur_desc->len, (unsigned long long)req->cur_desc->va);
+        break;
+    case SRP_DATA_DESC_INDIRECT:
+        req->ind_desc = (struct srp_indirect_buf *)(cmd->add_data + offset);
+        vscsi_swap_desc(&req->ind_desc->table_desc);
+        req->total_desc = req->ind_desc->table_desc.len /
+            sizeof(struct srp_direct_buf);
+        req->local_desc = req->writing ? cmd->data_out_desc_cnt :
+            cmd->data_in_desc_cnt;
+        for (i = 0; i < req->local_desc; i++) {
+            vscsi_swap_desc(&req->ind_desc->desc_list[i]);
+        }
+        req->cur_desc = req->local_desc ? &req->ind_desc->desc_list[0] : NULL;
+        dprintf("VSCSI: using indirect RDMA %s, 0x%x bytes %d descs "
+                "(%d local) VA: 0x%llx\n",
+                req->writing ? "read" : "write",
+                be32_to_cpu(req->ind_desc->len),
+                req->total_desc, req->local_desc,
+                (unsigned long long)req->ind_desc->table_desc.va);
+        break;
+    default:
+        fprintf(stderr,
+                "vscsi_preprocess_desc: Unknown format %x\n", req->dma_fmt);
+        return -1;
+    }
+
+    return 0;
+}
+
+/* Callback to indicate that the SCSI layer has completed a transfer.  */
+static void vscsi_transfer_data(SCSIRequest *sreq, uint32_t len)
+{
+    VSCSIState *s = DO_UPCAST(VSCSIState, vdev.qdev, sreq->bus->qbus.parent);
+    vscsi_req *req = sreq->hba_private;
+    uint8_t *buf;
+    int rc = 0;
+
+    dprintf("VSCSI: SCSI xfer complete tag=0x%x len=0x%x, req=%p\n",
+            sreq->tag, len, req);
+    if (req == NULL) {
+        fprintf(stderr, "VSCSI: Can't find request for tag 0x%x\n", sreq->tag);
+        return;
+    }
+
+    if (len) {
+        buf = scsi_req_get_buf(sreq);
+        rc = vscsi_srp_transfer_data(s, req, req->writing, buf, len);
+    }
+    if (rc < 0) {
+        fprintf(stderr, "VSCSI: RDMA error rc=%d!\n", rc);
+        vscsi_makeup_sense(s, req, HARDWARE_ERROR, 0, 0);
+        scsi_req_abort(req->sreq, CHECK_CONDITION);
+        return;
+    }
+
+    /* Start next chunk */
+    req->data_len -= rc;
+    scsi_req_continue(sreq);
+}
+
+/* Callback to indicate that the SCSI layer has completed a transfer.  */
+static void vscsi_command_complete(SCSIRequest *sreq, uint32_t status, size_t resid)
+{
+    VSCSIState *s = DO_UPCAST(VSCSIState, vdev.qdev, sreq->bus->qbus.parent);
+    vscsi_req *req = sreq->hba_private;
+    int32_t res_in = 0, res_out = 0;
+
+    dprintf("VSCSI: SCSI cmd complete, r=0x%x tag=0x%x status=0x%x, req=%p\n",
+            reason, sreq->tag, status, req);
+    if (req == NULL) {
+        fprintf(stderr, "VSCSI: Can't find request for tag 0x%x\n", sreq->tag);
+        return;
+    }
+
+    if (status == CHECK_CONDITION) {
+        req->senselen = scsi_req_get_sense(req->sreq, req->sense,
+                                           sizeof(req->sense));
+        dprintf("VSCSI: Sense data, %d bytes:\n", len);
+        dprintf("       %02x  %02x  %02x  %02x  %02x  %02x  %02x  %02x\n",
+                req->sense[0], req->sense[1], req->sense[2], req->sense[3],
+                req->sense[4], req->sense[5], req->sense[6], req->sense[7]);
+        dprintf("       %02x  %02x  %02x  %02x  %02x  %02x  %02x  %02x\n",
+                req->sense[8], req->sense[9], req->sense[10], req->sense[11],
+                req->sense[12], req->sense[13], req->sense[14], req->sense[15]);
+    }
+
+    dprintf("VSCSI: Command complete err=%d\n", status);
+    if (status == 0) {
+        /* We handle overflows, not underflows for normal commands,
+         * but hopefully nobody cares
+         */
+        if (req->writing) {
+            res_out = req->data_len;
+        } else {
+            res_in = req->data_len;
+        }
+    }
+    vscsi_send_rsp(s, req, status, res_in, res_out);
+    vscsi_put_req(req);
+}
+
+static void vscsi_request_cancelled(SCSIRequest *sreq)
+{
+    vscsi_req *req = sreq->hba_private;
+
+    vscsi_put_req(req);
+}
+
+static void vscsi_process_login(VSCSIState *s, vscsi_req *req)
+{
+    union viosrp_iu *iu = &req->iu;
+    struct srp_login_rsp *rsp = &iu->srp.login_rsp;
+    uint64_t tag = iu->srp.rsp.tag;
+
+    dprintf("VSCSI: Got login, sendin response !\n");
+
+    /* TODO handle case that requested size is wrong and
+     * buffer format is wrong
+     */
+    memset(iu, 0, sizeof(struct srp_login_rsp));
+    rsp->opcode = SRP_LOGIN_RSP;
+    /* Don't advertise quite as many request as we support to
+     * keep room for management stuff etc...
+     */
+    rsp->req_lim_delta = cpu_to_be32(VSCSI_REQ_LIMIT-2);
+    rsp->tag = tag;
+    rsp->max_it_iu_len = cpu_to_be32(sizeof(union srp_iu));
+    rsp->max_ti_iu_len = cpu_to_be32(sizeof(union srp_iu));
+    /* direct and indirect */
+    rsp->buf_fmt = cpu_to_be16(SRP_BUF_FORMAT_DIRECT | SRP_BUF_FORMAT_INDIRECT);
+
+    vscsi_send_iu(s, req, sizeof(*rsp), VIOSRP_SRP_FORMAT);
+}
+
+static void vscsi_inquiry_no_target(VSCSIState *s, vscsi_req *req)
+{
+    uint8_t *cdb = req->iu.srp.cmd.cdb;
+    uint8_t resp_data[36];
+    int rc, len, alen;
+
+    /* We dont do EVPD. Also check that page_code is 0 */
+    if ((cdb[1] & 0x01) || (cdb[1] & 0x01) || cdb[2] != 0) {
+        /* Send INVALID FIELD IN CDB */
+        vscsi_makeup_sense(s, req, ILLEGAL_REQUEST, 0x24, 0);
+        vscsi_send_rsp(s, req, CHECK_CONDITION, 0, 0);
+        return;
+    }
+    alen = cdb[3];
+    alen = (alen << 8) | cdb[4];
+    len = MIN(alen, 36);
+
+    /* Fake up inquiry using PQ=3 */
+    memset(resp_data, 0, 36);
+    resp_data[0] = 0x7f;   /* Not capable of supporting a device here */
+    resp_data[2] = 0x06;   /* SPS-4 */
+    resp_data[3] = 0x02;   /* Resp data format */
+    resp_data[4] = 36 - 5; /* Additional length */
+    resp_data[7] = 0x10;   /* Sync transfers */
+    memcpy(&resp_data[16], "QEMU EMPTY      ", 16);
+    memcpy(&resp_data[8], "QEMU    ", 8);
+
+    req->writing = 0;
+    vscsi_preprocess_desc(req);
+    rc = vscsi_srp_transfer_data(s, req, 0, resp_data, len);
+    if (rc < 0) {
+        vscsi_makeup_sense(s, req, HARDWARE_ERROR, 0, 0);
+        vscsi_send_rsp(s, req, CHECK_CONDITION, 0, 0);
+    } else {
+        vscsi_send_rsp(s, req, 0, 36 - rc, 0);
+    }
+}
+
+static int vscsi_queue_cmd(VSCSIState *s, vscsi_req *req)
+{
+    union srp_iu *srp = &req->iu.srp;
+    SCSIDevice *sdev;
+    int n, lun;
+
+    sdev = vscsi_device_find(&s->bus, be64_to_cpu(srp->cmd.lun), &lun);
+    if (!sdev) {
+        dprintf("VSCSI: Command for lun %08" PRIx64 " with no drive\n", be64_to_cpu(srp->cmd.lun));
+        if (srp->cmd.cdb[0] == INQUIRY) {
+            vscsi_inquiry_no_target(s, req);
+        } else {
+            vscsi_makeup_sense(s, req, ILLEGAL_REQUEST, 0x24, 0x00);
+            vscsi_send_rsp(s, req, CHECK_CONDITION, 0, 0);
+        } return 1;
+    }
+
+    req->lun = lun;
+    req->sreq = scsi_req_new(sdev, req->qtag, lun, srp->cmd.cdb, req);
+    n = scsi_req_enqueue(req->sreq);
+
+    dprintf("VSCSI: Queued command tag 0x%x CMD 0x%x ID %d LUN %d ret: %d\n",
+            req->qtag, srp->cmd.cdb[0], id, lun, n);
+
+    if (n) {
+        /* Transfer direction must be set before preprocessing the
+         * descriptors
+         */
+        req->writing = (n < 1);
+
+        /* Preprocess RDMA descriptors */
+        vscsi_preprocess_desc(req);
+
+        /* Get transfer direction and initiate transfer */
+        if (n > 0) {
+            req->data_len = n;
+        } else if (n < 0) {
+            req->data_len = -n;
+        }
+        scsi_req_continue(req->sreq);
+    }
+    /* Don't touch req here, it may have been recycled already */
+
+    return 0;
+}
+
+static int vscsi_process_tsk_mgmt(VSCSIState *s, vscsi_req *req)
+{
+    union viosrp_iu *iu = &req->iu;
+    int fn;
+
+    fprintf(stderr, "vscsi_process_tsk_mgmt %02x\n",
+            iu->srp.tsk_mgmt.tsk_mgmt_func);
+
+    switch (iu->srp.tsk_mgmt.tsk_mgmt_func) {
+#if 0 /* We really don't deal with these for now */
+    case SRP_TSK_ABORT_TASK:
+        fn = ABORT_TASK;
+        break;
+    case SRP_TSK_ABORT_TASK_SET:
+        fn = ABORT_TASK_SET;
+        break;
+    case SRP_TSK_CLEAR_TASK_SET:
+        fn = CLEAR_TASK_SET;
+        break;
+    case SRP_TSK_LUN_RESET:
+        fn = LOGICAL_UNIT_RESET;
+        break;
+    case SRP_TSK_CLEAR_ACA:
+        fn = CLEAR_ACA;
+        break;
+#endif
+    default:
+        fn = 0;
+    }
+    if (fn) {
+        /* XXX Send/Handle target task management */
+        ;
+    } else {
+        vscsi_makeup_sense(s, req, ILLEGAL_REQUEST, 0x20, 0);
+        vscsi_send_rsp(s, req, CHECK_CONDITION, 0, 0);
+    }
+    return !fn;
+}
+
+static int vscsi_handle_srp_req(VSCSIState *s, vscsi_req *req)
+{
+    union srp_iu *srp = &req->iu.srp;
+    int done = 1;
+    uint8_t opcode = srp->rsp.opcode;
+
+    switch (opcode) {
+    case SRP_LOGIN_REQ:
+        vscsi_process_login(s, req);
+        break;
+    case SRP_TSK_MGMT:
+        done = vscsi_process_tsk_mgmt(s, req);
+        break;
+    case SRP_CMD:
+        done = vscsi_queue_cmd(s, req);
+        break;
+    case SRP_LOGIN_RSP:
+    case SRP_I_LOGOUT:
+    case SRP_T_LOGOUT:
+    case SRP_RSP:
+    case SRP_CRED_REQ:
+    case SRP_CRED_RSP:
+    case SRP_AER_REQ:
+    case SRP_AER_RSP:
+        fprintf(stderr, "VSCSI: Unsupported opcode %02x\n", opcode);
+        break;
+    default:
+        fprintf(stderr, "VSCSI: Unknown type %02x\n", opcode);
+    }
+
+    return done;
+}
+
+static int vscsi_send_adapter_info(VSCSIState *s, vscsi_req *req)
+{
+    struct viosrp_adapter_info *sinfo;
+    struct mad_adapter_info_data info;
+    int rc;
+
+    sinfo = &req->iu.mad.adapter_info;
+
+#if 0 /* What for ? */
+    rc = spapr_vio_dma_read(&s->vdev, be64_to_cpu(sinfo->buffer),
+                            &info, be16_to_cpu(sinfo->common.length));
+    if (rc) {
+        fprintf(stderr, "vscsi_send_adapter_info: DMA read failure !\n");
+    }
+#endif
+    memset(&info, 0, sizeof(info));
+    strcpy(info.srp_version, SRP_VERSION);
+    memcpy(info.partition_name, "qemu", sizeof("qemu"));
+    info.partition_number = cpu_to_be32(0);
+    info.mad_version = cpu_to_be32(1);
+    info.os_type = cpu_to_be32(2);
+    info.port_max_txu[0] = cpu_to_be32(VSCSI_MAX_SECTORS << 9);
+
+    rc = spapr_vio_dma_write(&s->vdev, be64_to_cpu(sinfo->buffer),
+                             &info, be16_to_cpu(sinfo->common.length));
+    if (rc)  {
+        fprintf(stderr, "vscsi_send_adapter_info: DMA write failure !\n");
+    }
+
+    sinfo->common.status = rc ? cpu_to_be32(1) : 0;
+
+    return vscsi_send_iu(s, req, sizeof(*sinfo), VIOSRP_MAD_FORMAT);
+}
+
+static int vscsi_handle_mad_req(VSCSIState *s, vscsi_req *req)
+{
+    union mad_iu *mad = &req->iu.mad;
+
+    switch (be32_to_cpu(mad->empty_iu.common.type)) {
+    case VIOSRP_EMPTY_IU_TYPE:
+        fprintf(stderr, "Unsupported EMPTY MAD IU\n");
+        break;
+    case VIOSRP_ERROR_LOG_TYPE:
+        fprintf(stderr, "Unsupported ERROR LOG MAD IU\n");
+        mad->error_log.common.status = cpu_to_be16(1);
+        vscsi_send_iu(s, req, sizeof(mad->error_log), VIOSRP_MAD_FORMAT);
+        break;
+    case VIOSRP_ADAPTER_INFO_TYPE:
+        vscsi_send_adapter_info(s, req);
+        break;
+    case VIOSRP_HOST_CONFIG_TYPE:
+        mad->host_config.common.status = cpu_to_be16(1);
+        vscsi_send_iu(s, req, sizeof(mad->host_config), VIOSRP_MAD_FORMAT);
+        break;
+    default:
+        fprintf(stderr, "VSCSI: Unknown MAD type %02x\n",
+                be32_to_cpu(mad->empty_iu.common.type));
+    }
+
+    return 1;
+}
+
+static void vscsi_got_payload(VSCSIState *s, vscsi_crq *crq)
+{
+    vscsi_req *req;
+    int done;
+
+    req = vscsi_get_req(s);
+    if (req == NULL) {
+        fprintf(stderr, "VSCSI: Failed to get a request !\n");
+        return;
+    }
+
+    /* We only support a limited number of descriptors, we know
+     * the ibmvscsi driver uses up to 10 max, so it should fit
+     * in our 256 bytes IUs. If not we'll have to increase the size
+     * of the structure.
+     */
+    if (crq->s.IU_length > sizeof(union viosrp_iu)) {
+        fprintf(stderr, "VSCSI: SRP IU too long (%d bytes) !\n",
+                crq->s.IU_length);
+        vscsi_put_req(req);
+        return;
+    }
+
+    /* XXX Handle failure differently ? */
+    if (spapr_vio_dma_read(&s->vdev, crq->s.IU_data_ptr, &req->iu,
+                           crq->s.IU_length)) {
+        fprintf(stderr, "vscsi_got_payload: DMA read failure !\n");
+        vscsi_put_req(req);
+        return;
+    }
+    memcpy(&req->crq, crq, sizeof(vscsi_crq));
+
+    if (crq->s.format == VIOSRP_MAD_FORMAT) {
+        done = vscsi_handle_mad_req(s, req);
+    } else {
+        done = vscsi_handle_srp_req(s, req);
+    }
+
+    if (done) {
+        vscsi_put_req(req);
+    }
+}
+
+
+static int vscsi_do_crq(struct VIOsPAPRDevice *dev, uint8_t *crq_data)
+{
+    VSCSIState *s = DO_UPCAST(VSCSIState, vdev, dev);
+    vscsi_crq crq;
+
+    memcpy(crq.raw, crq_data, 16);
+    crq.s.timeout = be16_to_cpu(crq.s.timeout);
+    crq.s.IU_length = be16_to_cpu(crq.s.IU_length);
+    crq.s.IU_data_ptr = be64_to_cpu(crq.s.IU_data_ptr);
+
+    dprintf("VSCSI: do_crq %02x %02x ...\n", crq.raw[0], crq.raw[1]);
+
+    switch (crq.s.valid) {
+    case 0xc0: /* Init command/response */
+
+        /* Respond to initialization request */
+        if (crq.s.format == 0x01) {
+            memset(crq.raw, 0, 16);
+            crq.s.valid = 0xc0;
+            crq.s.format = 0x02;
+            spapr_vio_send_crq(dev, crq.raw);
+        }
+
+        /* Note that in hotplug cases, we might get a 0x02
+         * as a result of us emitting the init request
+         */
+
+        break;
+    case 0xff: /* Link event */
+
+        /* Not handled for now */
+
+        break;
+    case 0x80: /* Payloads */
+        switch (crq.s.format) {
+        case VIOSRP_SRP_FORMAT: /* AKA VSCSI request */
+        case VIOSRP_MAD_FORMAT: /* AKA VSCSI response */
+            vscsi_got_payload(s, &crq);
+            break;
+        case VIOSRP_OS400_FORMAT:
+        case VIOSRP_AIX_FORMAT:
+        case VIOSRP_LINUX_FORMAT:
+        case VIOSRP_INLINE_FORMAT:
+            fprintf(stderr, "vscsi_do_srq: Unsupported payload format %02x\n",
+                    crq.s.format);
+            break;
+        default:
+            fprintf(stderr, "vscsi_do_srq: Unknown payload format %02x\n",
+                    crq.s.format);
+        }
+        break;
+    default:
+        fprintf(stderr, "vscsi_do_crq: unknown CRQ %02x %02x ...\n",
+                crq.raw[0], crq.raw[1]);
+    };
+
+    return 0;
+}
+
+static const struct SCSIBusInfo vscsi_scsi_info = {
+    .tcq = true,
+    .max_channel = 7, /* logical unit addressing format */
+    .max_target = 63,
+    .max_lun = 31,
+
+    .transfer_data = vscsi_transfer_data,
+    .complete = vscsi_command_complete,
+    .cancel = vscsi_request_cancelled
+};
+
+static void spapr_vscsi_reset(VIOsPAPRDevice *dev)
+{
+    VSCSIState *s = DO_UPCAST(VSCSIState, vdev, dev);
+    int i;
+
+    memset(s->reqs, 0, sizeof(s->reqs));
+    for (i = 0; i < VSCSI_REQ_LIMIT; i++) {
+        s->reqs[i].qtag = i;
+    }
+}
+
+static int spapr_vscsi_init(VIOsPAPRDevice *dev)
+{
+    VSCSIState *s = DO_UPCAST(VSCSIState, vdev, dev);
+
+    dev->crq.SendFunc = vscsi_do_crq;
+
+    scsi_bus_new(&s->bus, &dev->qdev, &vscsi_scsi_info);
+    if (!dev->qdev.hotplugged) {
+        scsi_bus_legacy_handle_cmdline(&s->bus);
+    }
+
+    return 0;
+}
+
+void spapr_vscsi_create(VIOsPAPRBus *bus)
+{
+    DeviceState *dev;
+
+    dev = qdev_create(&bus->bus, "spapr-vscsi");
+
+    qdev_init_nofail(dev);
+}
+
+static int spapr_vscsi_devnode(VIOsPAPRDevice *dev, void *fdt, int node_off)
+{
+    int ret;
+
+    ret = fdt_setprop_cell(fdt, node_off, "#address-cells", 2);
+    if (ret < 0) {
+        return ret;
+    }
+
+    ret = fdt_setprop_cell(fdt, node_off, "#size-cells", 0);
+    if (ret < 0) {
+        return ret;
+    }
+
+    return 0;
+}
+
+static Property spapr_vscsi_properties[] = {
+    DEFINE_SPAPR_PROPERTIES(VSCSIState, vdev),
+    DEFINE_PROP_END_OF_LIST(),
+};
+
+static void spapr_vscsi_class_init(ObjectClass *klass, void *data)
+{
+    DeviceClass *dc = DEVICE_CLASS(klass);
+    VIOsPAPRDeviceClass *k = VIO_SPAPR_DEVICE_CLASS(klass);
+
+    k->init = spapr_vscsi_init;
+    k->reset = spapr_vscsi_reset;
+    k->devnode = spapr_vscsi_devnode;
+    k->dt_name = "v-scsi";
+    k->dt_type = "vscsi";
+    k->dt_compatible = "IBM,v-scsi";
+    k->signal_mask = 0x00000001;
+    dc->props = spapr_vscsi_properties;
+    k->rtce_window_size = 0x10000000;
+}
+
+static const TypeInfo spapr_vscsi_info = {
+    .name          = "spapr-vscsi",
+    .parent        = TYPE_VIO_SPAPR_DEVICE,
+    .instance_size = sizeof(VSCSIState),
+    .class_init    = spapr_vscsi_class_init,
+};
+
+static void spapr_vscsi_register_types(void)
+{
+    type_register_static(&spapr_vscsi_info);
+}
+
+type_init(spapr_vscsi_register_types)