Re: [Qemu-devel] [PATCH RFC v3 4/5] ATAPI-SCSI bridge functions created an can be used by bridge

[Hannes Reinecke <hare@suse.de>]

On 08/19/2015 12:57 PM, Alexander Bezzubikov wrote:
> ide: bridge functions created
> ide: Makefile corrected due to bridge creation
> scsi: added function to enable bridge send SCSI requests
> ide: bridge can now forward requests to SCSI
> ide: bridge functions assigned to SCSIBusInfo
> Signed-off-by: Alexander Bezzubikov <abezzubikov@ispras.ru>
> ---
>  hw/ide/Makefile.objs   |   2 +-
>  hw/ide/atapi.c         |  16 +++++++
>  hw/ide/bridge.c        | 114 +++++++++++++++++++++++++++++++++++++++++++++++++
>  hw/ide/bridge.h        |   1 +
>  hw/ide/internal.h      |   2 +
>  hw/ide/qdev.c          |   4 +-
>  hw/scsi/scsi-disk.c    |  43 +++++++++++++++++++
>  include/hw/scsi/scsi.h |   3 ++
>  8 files changed, 182 insertions(+), 3 deletions(-)
>  create mode 100644 hw/ide/bridge.c
> 
> diff --git a/hw/ide/Makefile.objs b/hw/ide/Makefile.objs
> index 729e9bd..f54f275 100644
> --- a/hw/ide/Makefile.objs
> +++ b/hw/ide/Makefile.objs
> @@ -1,4 +1,4 @@
> -common-obj-$(CONFIG_IDE_CORE) += core.o atapi.o
> +common-obj-$(CONFIG_IDE_CORE) += core.o atapi.o bridge.o
>  common-obj-$(CONFIG_IDE_QDEV) += qdev.o
>  common-obj-$(CONFIG_IDE_PCI) += pci.o
>  common-obj-$(CONFIG_IDE_ISA) += isa.o
> diff --git a/hw/ide/atapi.c b/hw/ide/atapi.c
> index f6135e1..3eb56e2 100644
> --- a/hw/ide/atapi.c
> +++ b/hw/ide/atapi.c
> @@ -1253,6 +1253,22 @@ void ide_atapi_cmd(IDEState *s)
>          return;
>      }
>  
> +    if (s->drive_kind == IDE_BRIDGE) {
> +        IDEDevice *dev = s->bus->master;
> +        SCSIDevice *scsi_dev = scsi_device_find(&dev->scsi_bus, 0, 0, 0);
> +        s->cur_req = scsi_new_request_from_bridge(scsi_dev, 0, 0, buf, NULL);
> +
> +        /* Necessary to prevent ide from reading while data isn't ready */
> +        if (buf[0] == READ_10) {
> +            s->status |= BUSY_STAT;
> +        }
> +
> +        if (scsi_req_enqueue(s->cur_req)) {
> +            scsi_req_continue(s->cur_req);
> +        }
> +        return;
> +    }
> +
>      /* Execute the command */
>      if (atapi_cmd_table[s->io_buffer[0]].handler) {
>          atapi_cmd_table[s->io_buffer[0]].handler(s, buf);
> diff --git a/hw/ide/bridge.c b/hw/ide/bridge.c
> new file mode 100644
> index 0000000..2e93311
> --- /dev/null
> +++ b/hw/ide/bridge.c
> @@ -0,0 +1,114 @@
> +#include "hw/ide/bridge.h"
> +
> +void ide_bridge_do_transfer(IDEState *s)
> +{
> +    SCSIDiskReq *r = DO_UPCAST(SCSIDiskReq, req, s->cur_req);
> +
> +    if (r->buflen > 0) {
> +        int size = r->buflen;
> +
> +        int byte_count_limit = s->lcyl | (s->hcyl << 8);
> +        if (byte_count_limit == 0xffff) {
> +            byte_count_limit--;
> +        }
> +        if (size > byte_count_limit) {
> +            /* byte count limit must be even if this case */
> +            if (byte_count_limit & 1) {
> +                byte_count_limit--;
> +            }
> +            size = byte_count_limit;
> +        }
> +        s->lcyl = size;
> +        s->hcyl = size >> 8;
> +        s->nsector = (s->nsector & ~7) | ATAPI_INT_REASON_IO;
> +
> +        int offset = (r->buflen == r->qiov.size) ? 0 : r->qiov.size - r->buflen;
> +        r->buflen -= size;
> +
> +        ide_transfer_start(s, s->io_buffer + offset, size,
> +                           ide_bridge_do_transfer);
> +        ide_set_irq(s->bus);
> +    } else {
> +        scsi_req_complete(s->cur_req, GOOD);
> +    }
> +}
> +
> +static void ide_bridge_dma_complete(void *opaque, int ret)
> +{
> +    IDEState *s = opaque;
> +
> +    s->io_buffer_size = s->bus->dma->iov.iov_len;
> +    s->nsector = (s->nsector & ~7) | ATAPI_INT_REASON_IO | ATAPI_INT_REASON_CD;
> +    s->bus->dma->ops->rw_buf(s->bus->dma, 1);
> +    scsi_req_complete(s->cur_req, GOOD);
> +
> +    s->status = READY_STAT | SEEK_STAT;
> +
> +    ide_set_irq(s->bus);
> +    ide_set_inactive(s, false);
> +}
> +
> +void ide_bridge_start_transfer(SCSIRequest *req, uint32_t len)
> +{
> +    IDEDevice *dev = IDE_DEVICE(req->bus->qbus.parent);
> +    IDEBus *bus = DO_UPCAST(IDEBus, qbus, dev->qdev.parent_bus);
> +    IDEState *s = bus->ifs;
> +    SCSIDiskReq *r = DO_UPCAST(SCSIDiskReq, req, req);
> +
> +    int cmd = req->cmd.buf[0];
> +    if (cmd == READ_10) {
> +        if (s->feature & 1) {
> +            s->status = READY_STAT | SEEK_STAT | DRQ_STAT | BUSY_STAT;
> +            qemu_iovec_clone(&s->bus->dma->qiov, &r->qiov, NULL);
> +            qemu_iovec_to_buf(&r->qiov, 0, s->io_buffer, r->qiov.size);
> +        } else {
> +            qemu_iovec_to_buf(&r->qiov, 0, s->io_buffer, r->qiov.size);
> +        }
> +    } else {
> +        if (cmd == INQUIRY) {
> +            len = 36;
> +        }
> +        r->iov.iov_len = len;
> +        qemu_iovec_concat_iov(&r->qiov, &r->iov, len, 0, len);
> +        qemu_iovec_to_buf(&r->qiov, 0, s->io_buffer, r->qiov.size);
> +    }
> +
> +    s->io_buffer_index = 0;
> +    s->status = READY_STAT | SEEK_STAT;
> +
> +    if (cmd != TEST_UNIT_READY && cmd != ALLOW_MEDIUM_REMOVAL) {
> +        if (s->feature & 1) {
> +            s->io_buffer_index = 0;
> +            s->bus->retry_unit = s->unit;
> +            s->bus->retry_sector_num = ide_get_sector(s);
> +            s->bus->retry_nsector = s->nsector;
> +
> +            s->bus->dma->iov.iov_base = (void *)(s->io_buffer);
> +            s->bus->dma->iov.iov_len = r->qiov.size;
> +
> +            if (cmd != READ_10) {
> +                s->status = READY_STAT | SEEK_STAT | DRQ_STAT;
> +            }
> +
> +            if (s->bus->dma->ops->start_dma) {
> +                s->bus->dma->ops->start_dma(s->bus->dma, s,
> +                                            ide_bridge_dma_complete);
> +            }
> +        } else {
> +            r->buflen = r->qiov.size;
> +            ide_bridge_do_transfer(s);
> +        }
> +    } else {
> +        scsi_req_complete(req, GOOD);
> +    }
> +}
> +
> +void ide_bridge_complete(SCSIRequest *req, uint32_t status, size_t resid)
> +{
> +    IDEDevice *dev = IDE_DEVICE(req->bus->qbus.parent);
> +    IDEBus *bus = DO_UPCAST(IDEBus, qbus, dev->qdev.parent_bus);
> +    IDEState *s = bus->ifs;
> +
> +    ide_atapi_cmd_ok(s);
> +    ide_set_irq(s->bus);
> +}
> diff --git a/hw/ide/bridge.h b/hw/ide/bridge.h
> index dca5d73..59f2f25 100644
> --- a/hw/ide/bridge.h
> +++ b/hw/ide/bridge.h
> @@ -5,5 +5,6 @@
>  
>  void ide_bridge_start_transfer(SCSIRequest *req, uint32_t len);
>  void ide_bridge_complete(SCSIRequest *req, uint32_t status, size_t resid);
> +void ide_bridge_do_transfer(IDEState *s);
>  
>  #endif
> diff --git a/hw/ide/internal.h b/hw/ide/internal.h
> index 79c85be..fd385bc 100644
> --- a/hw/ide/internal.h
> +++ b/hw/ide/internal.h
> @@ -429,6 +429,8 @@ struct IDEState {
>      uint8_t *smart_selftest_data;
>      /* AHCI */
>      int ncq_queues;
> +    /* ATAPI-SCSI bridge */
> +    SCSIRequest *cur_req;
>  };
>  
>  struct IDEDMAOps {
As discussed on the list, can you rename 'cur_req' to 'scsi_req' ?

Thanks.

Cheers,

Hannes
-- 
Dr. Hannes Reinecke		               zSeries & Storage
hare@suse.de			               +49 911 74053 688
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