Re: [Xen-devel] [PATCH 2/3] x86/vMSI-X: also snoop qword writes

[Paul Durrant <Paul.Durrant@xxxxxxxxxx>]

> -----Original Message-----
> From: Jan Beulich [mailto:JBeulich@xxxxxxxx]
> Sent: 28 April 2016 10:50
> To: xen-devel
> Cc: Andrew Cooper; Paul Durrant
> Subject: [PATCH 2/3] x86/vMSI-X: also snoop qword writes
> 
> ... the high half of which may be a write to the Vector Control field.
> This gets things in sync again with msixtbl_write().
> 
> Signed-off-by: Jan Beulich <jbeulich@xxxxxxxx>

Reviewed-by: Paul Durrant <paul.durrant@xxxxxxxxxx>

> 
> --- a/xen/arch/x86/hvm/vmsi.c
> +++ b/xen/arch/x86/hvm/vmsi.c
> @@ -336,6 +336,7 @@ out:
>  static int msixtbl_range(struct vcpu *v, unsigned long addr)
>  {
>      const struct msi_desc *desc;
> +    const ioreq_t *r;
> 
>      rcu_read_lock(&msixtbl_rcu_lock);
>      desc = msixtbl_addr_to_desc(msixtbl_find_entry(v, addr), addr);
> @@ -344,17 +345,29 @@ static int msixtbl_range(struct vcpu *v,
>      if ( desc )
>          return 1;
> 
> -    if ( (addr & (PCI_MSIX_ENTRY_SIZE - 1)) ==
> -         PCI_MSIX_ENTRY_VECTOR_CTRL_OFFSET )
> +    r = &v->arch.hvm_vcpu.hvm_io.io_req;
> +    if ( r->state != STATE_IOREQ_READY || r->addr != addr )
> +        return 0;
> +    ASSERT(r->type == IOREQ_TYPE_COPY);
> +    if ( r->dir == IOREQ_WRITE )
>      {
> -        const ioreq_t *r = &v->arch.hvm_vcpu.hvm_io.io_req;
> +        if ( !r->data_is_ptr )
> +        {
> +            unsigned int size = r->size;
> +            uint64_t data = r->data;
> 
> -        if ( r->state != STATE_IOREQ_READY || r->addr != addr )
> -            return 0;
> -        ASSERT(r->type == IOREQ_TYPE_COPY);
> -        if ( r->dir == IOREQ_WRITE && r->size == 4 && !r->data_is_ptr
> -             && !(r->data & PCI_MSIX_VECTOR_BITMASK) )
> -            v->arch.hvm_vcpu.hvm_io.msix_snoop_address = addr;
> +            if ( size == 8 )
> +            {
> +                BUILD_BUG_ON(!(PCI_MSIX_ENTRY_VECTOR_CTRL_OFFSET & 4));
> +                data >>= 32;
> +                addr += size = 4;
> +            }
> +            if ( size == 4 &&
> +                 ((addr & (PCI_MSIX_ENTRY_SIZE - 1)) ==
> +                  PCI_MSIX_ENTRY_VECTOR_CTRL_OFFSET) &&
> +                 !(data & PCI_MSIX_VECTOR_BITMASK) )
> +                v->arch.hvm_vcpu.hvm_io.msix_snoop_address = addr;
> +        }
>      }
> 
>      return 0;
> 
> 


_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxx
http://lists.xen.org/xen-devel