Re: [Qemu-devel] [PATCH v2 1/3] Stop VM on ENOSPC error.

[Anthony Liguori <anthony@codemonkey.ws>]

Gleb Natapov wrote:
> And repeat last IDE command after VM restart.
>
> Signed-off-by: Gleb Natapov <gleb@redhat.com>
> ---
>
>  hw/ide.c |   54 ++++++++++++++++++++++++++++++++++++++++++++++++++----
>  1 files changed, 50 insertions(+), 4 deletions(-)
>
> diff --git a/hw/ide.c b/hw/ide.c
> index 7dd41f7..2d2cead 100644
> --- a/hw/ide.c
> +++ b/hw/ide.c
> @@ -457,6 +457,8 @@ static inline int media_is_cd(IDEState *s)
>  #define BM_STATUS_DMAING 0x01
>  #define BM_STATUS_ERROR  0x02
>  #define BM_STATUS_INT    0x04
> +#define BM_STATUS_DMA_RETRY  0x08
> +#define BM_STATUS_PIO_RETRY  0x10
>  
>  #define BM_CMD_START     0x01
>  #define BM_CMD_READ      0x08
> @@ -488,6 +490,8 @@ typedef struct BMDMAState {
>      IDEState *ide_if;
>      BlockDriverCompletionFunc *dma_cb;
>      BlockDriverAIOCB *aiocb;
> +    int64_t sector_num;
> +    uint32_t nsector;
>  } BMDMAState;
>  
>  typedef struct PCIIDEState {
> @@ -498,6 +502,7 @@ typedef struct PCIIDEState {
>  } PCIIDEState;
>  
>  static void ide_dma_start(IDEState *s, BlockDriverCompletionFunc *dma_cb);
> +static void ide_dma_restart(IDEState *s);
>  static void ide_atapi_cmd_read_dma_cb(void *opaque, int ret);
>  
>  static void padstr(char *str, const char *src, int len)
> @@ -991,8 +996,13 @@ static void ide_sector_write(IDEState *s)
>          n = s->req_nb_sectors;
>      ret = bdrv_write(s->bs, sector_num, s->io_buffer, n);
>      if (ret != 0) {
> -	ide_rw_error(s);
> -	return;
> +        if (ret == -ENOSPC) {
> +            s->bmdma->ide_if = s;
> +            s->bmdma->status |= BM_STATUS_PIO_RETRY;
> +            vm_stop(0);
> +        } else
> +            ide_rw_error(s);
> +        return;
>      }
>  
>      s->nsector -= n;
> @@ -1024,6 +1034,20 @@ static void ide_sector_write(IDEState *s)
>      }
>  }
>  
> +static void ide_dma_restart_cb(void *opaque, int running)
> +{
> +    BMDMAState *bm = opaque;
> +    if (!running)
> +        return;
> +    if (bm->status & BM_STATUS_DMA_RETRY) {
> +        bm->status &= ~BM_STATUS_DMA_RETRY;
> +        ide_dma_restart(bm->ide_if);
> +    } else if (bm->status & BM_STATUS_PIO_RETRY) {
> +        bm->status &= ~BM_STATUS_PIO_RETRY;
> +        ide_sector_write(bm->ide_if);
> +    }
> +}
> +
>  static void ide_write_dma_cb(void *opaque, int ret)
>  {
>      BMDMAState *bm = opaque;
> @@ -1032,8 +1056,12 @@ static void ide_write_dma_cb(void *opaque, int ret)
>      int64_t sector_num;
>  
>      if (ret < 0) {
> -	ide_dma_error(s);
> -	return;
> +        if (ret == -ENOSPC) {
> +            bm->status |= BM_STATUS_DMA_RETRY;
> +            vm_stop(0);
> +        } else
> +            ide_dma_error(s);
> +        return;
>      }
>  
>      n = s->io_buffer_size >> 9;
> @@ -2849,11 +2877,24 @@ static void ide_dma_start(IDEState *s, BlockDriverCompletionFunc *dma_cb)
>      bm->cur_prd_last = 0;
>      bm->cur_prd_addr = 0;
>      bm->cur_prd_len = 0;
> +    bm->sector_num = ide_get_sector(s);
> +    bm->nsector = s->nsector;
>      if (bm->status & BM_STATUS_DMAING) {
>          bm->dma_cb(bm, 0);
>      }
>  }
>  
> +static void ide_dma_restart(IDEState *s)
> +{
> +    BMDMAState *bm = s->bmdma;
> +    ide_set_sector(s, bm->sector_num);
> +    s->io_buffer_index = 0;
> +    s->io_buffer_size = 0;
> +    s->nsector = bm->nsector;
> +    bm->cur_addr = bm->addr;
> +    ide_dma_start(s, bm->dma_cb);
> +}
> +
>  static void ide_dma_cancel(BMDMAState *bm)
>  {
>      if (bm->status & BM_STATUS_DMAING) {
> @@ -3043,6 +3084,7 @@ static void bmdma_map(PCIDevice *pci_dev, int region_num,
>          d->ide_if[2 * i].bmdma = bm;
>          d->ide_if[2 * i + 1].bmdma = bm;
>          bm->pci_dev = (PCIIDEState *)pci_dev;
> +        qemu_add_vm_change_state_handler(ide_dma_restart_cb, bm);
>  
>          register_ioport_write(addr, 1, 1, bmdma_cmd_writeb, bm);
>  
> @@ -3071,6 +3113,8 @@ static void pci_ide_save(QEMUFile* f, void *opaque)
>          qemu_put_8s(f, &bm->cmd);
>          qemu_put_8s(f, &bm->status);
>          qemu_put_be32s(f, &bm->addr);
> +        qemu_put_sbe64s(f, &bm->sector_num);
> +        qemu_put_be32s(f, &bm->nsector);
>   

If you're adding to the save/restore format, you have to increment the 
version number.

Regards,

Anthony Liguori

>          /* XXX: if a transfer is pending, we do not save it yet */
>      }
>  
> @@ -3105,6 +3149,8 @@ static int pci_ide_load(QEMUFile* f, void *opaque, int version_id)
>          qemu_get_8s(f, &bm->cmd);
>          qemu_get_8s(f, &bm->status);
>          qemu_get_be32s(f, &bm->addr);
> +        qemu_get_sbe64s(f, &bm->sector_num);
> +        qemu_get_be32s(f, &bm->nsector);
>          /* XXX: if a transfer is pending, we do not save it yet */
>      }
>  
>
>
>
>