[v2] IOREQ feature (+ virtio-mmio) on Arm

[PATCH V2 04/23] xen/ioreq: Provide alias for the handle_mmio()

Posted by Oleksandr Tyshchenko 5 years, 3 months ago

From: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com>

The IOREQ is a common feature now and Arm will have its own
implementation.

But the name of the function is pretty generic and can be confusing
on Arm (we already have a try_handle_mmio()).

In order not to rename the function (which is used for a varying
set of purposes on x86) globally and get non-confusing variant on Arm
provide an alias ioreq_complete_mmio() to be used on common and
Arm code.

Signed-off-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com>
CC: Julien Grall <julien.grall@arm.com>
Acked-by: Jan Beulich <jbeulich@suse.com>

---
Please note, this is a split/cleanup/hardening of Julien's PoC:
"Add support for Guest IO forwarding to a device emulator"

Changes RFC -> V1:
   - new patch

Changes V1 -> V2:
   - remove "handle"
   - add Jan's A-b
---
 xen/common/ioreq.c              | 2 +-
 xen/include/asm-x86/hvm/ioreq.h | 2 ++
 2 files changed, 3 insertions(+), 1 deletion(-)

diff --git a/xen/common/ioreq.c b/xen/common/ioreq.c
index c89df7a..29ad48e 100644
--- a/xen/common/ioreq.c
+++ b/xen/common/ioreq.c
@@ -200,7 +200,7 @@ bool handle_hvm_io_completion(struct vcpu *v)
         break;
 
     case HVMIO_mmio_completion:
-        return handle_mmio();
+        return ioreq_complete_mmio();
 
     case HVMIO_pio_completion:
         return handle_pio(vio->io_req.addr, vio->io_req.size,
diff --git a/xen/include/asm-x86/hvm/ioreq.h b/xen/include/asm-x86/hvm/ioreq.h
index a3d8faa..a147856 100644
--- a/xen/include/asm-x86/hvm/ioreq.h
+++ b/xen/include/asm-x86/hvm/ioreq.h
@@ -181,6 +181,8 @@ static inline bool arch_hvm_ioreq_destroy(struct domain *d)
 #define IOREQ_STATUS_UNHANDLED   X86EMUL_UNHANDLEABLE
 #define IOREQ_STATUS_RETRY       X86EMUL_RETRY
 
+#define ioreq_complete_mmio   handle_mmio
+
 #endif /* __ASM_X86_HVM_IOREQ_H__ */
 
 /*
-- 
2.7.4

RE: [PATCH V2 04/23] xen/ioreq: Provide alias for the handle_mmio()

Posted by Paul Durrant 5 years, 3 months ago

> -----Original Message-----
> From: Xen-devel <xen-devel-bounces@lists.xenproject.org> On Behalf Of Oleksandr Tyshchenko
> Sent: 15 October 2020 17:44
> To: xen-devel@lists.xenproject.org
> Cc: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com>; Paul Durrant <paul@xen.org>; Jan Beulich
> <jbeulich@suse.com>; Andrew Cooper <andrew.cooper3@citrix.com>; Roger Pau Monné
> <roger.pau@citrix.com>; Wei Liu <wl@xen.org>; Julien Grall <julien@xen.org>; Stefano Stabellini
> <sstabellini@kernel.org>; Julien Grall <julien.grall@arm.com>
> Subject: [PATCH V2 04/23] xen/ioreq: Provide alias for the handle_mmio()
> 
> From: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com>
> 
> The IOREQ is a common feature now and Arm will have its own
> implementation.
> 
> But the name of the function is pretty generic and can be confusing
> on Arm (we already have a try_handle_mmio()).
> 
> In order not to rename the function (which is used for a varying
> set of purposes on x86) globally and get non-confusing variant on Arm
> provide an alias ioreq_complete_mmio() to be used on common and
> Arm code.
> 
> Signed-off-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com>
> CC: Julien Grall <julien.grall@arm.com>
> Acked-by: Jan Beulich <jbeulich@suse.com>
> 
> ---
> Please note, this is a split/cleanup/hardening of Julien's PoC:
> "Add support for Guest IO forwarding to a device emulator"
> 
> Changes RFC -> V1:
>    - new patch
> 
> Changes V1 -> V2:
>    - remove "handle"
>    - add Jan's A-b
> ---
>  xen/common/ioreq.c              | 2 +-
>  xen/include/asm-x86/hvm/ioreq.h | 2 ++
>  2 files changed, 3 insertions(+), 1 deletion(-)
> 
> diff --git a/xen/common/ioreq.c b/xen/common/ioreq.c
> index c89df7a..29ad48e 100644
> --- a/xen/common/ioreq.c
> +++ b/xen/common/ioreq.c
> @@ -200,7 +200,7 @@ bool handle_hvm_io_completion(struct vcpu *v)
>          break;
> 
>      case HVMIO_mmio_completion:
> -        return handle_mmio();
> +        return ioreq_complete_mmio();
> 
>      case HVMIO_pio_completion:
>          return handle_pio(vio->io_req.addr, vio->io_req.size,
> diff --git a/xen/include/asm-x86/hvm/ioreq.h b/xen/include/asm-x86/hvm/ioreq.h
> index a3d8faa..a147856 100644
> --- a/xen/include/asm-x86/hvm/ioreq.h
> +++ b/xen/include/asm-x86/hvm/ioreq.h
> @@ -181,6 +181,8 @@ static inline bool arch_hvm_ioreq_destroy(struct domain *d)
>  #define IOREQ_STATUS_UNHANDLED   X86EMUL_UNHANDLEABLE
>  #define IOREQ_STATUS_RETRY       X86EMUL_RETRY
> 
> +#define ioreq_complete_mmio   handle_mmio
> +

A #define? Really? Can we not have a static inline?

  Paul

>  #endif /* __ASM_X86_HVM_IOREQ_H__ */
> 
>  /*
> --
> 2.7.4
>