[PATCH] tools/virtio: fix build caused by virtio_ring changes

Shunsuke Mie
Mon, 10 Apr 2023 10:56:13 -0000

On 2023/04/10 19:00, Shunsuke Mie wrote:
>
> On 2023/04/10 18:46, Michael S. Tsirkin wrote:
>> On Mon, Apr 10, 2023 at 06:24:19PM +0900, Shunsuke Mie wrote:
>>> Fix the build dependency for virtio_test. virtio_ring requires
>>> container_of_const() and struce device.
>>>
>>> Signed-off-by: Shunsuke Mie <mie at igel.co.jp>
>>> ---
>>> ? tools/include/linux/container_of.h | 36
>>> ++++++++++++++++++++++++++++++
>>> ? tools/virtio/linux/compiler.h????? |? 3 +++
>>> ? tools/virtio/linux/kernel.h??????? |? 5 +----
>>> ? tools/virtio/linux/module.h??????? |? 1 +
>>> ? 4 files changed, 41 insertions(+), 4 deletions(-)
>>> ? create mode 100644 tools/include/linux/container_of.h
>>>
>>> diff --git a/tools/include/linux/container_of.h
>>> b/tools/include/linux/container_of.h
>>> new file mode 100644
>>> index 000000000000..06e293b7cfda
>>> --- /dev/null
>>> +++ b/tools/include/linux/container_of.h
>>> @@ -0,0 +1,36 @@
>>> +/* SPDX-License-Identifier: GPL-2.0 */
>>> +#ifndef _LINUX_CONTAINER_OF_H
>>> +#define _LINUX_CONTAINER_OF_H
>>> +
>>> +#include <linux/build_bug.h>
>>> +#include <linux/stddef.h>
>>> +
>>> +/**
>>> + * container_of - cast a member of a structure out to the
>>> containing structure
>>> + * @ptr:??? the pointer to the member.
>>> + * @type:??? the type of the container struct this is embedded in.
>>> + * @member:??? the name of the member within the struct.
>>> + *
>>> + * WARNING: any const qualifier of @ptr is lost.
>>> + */
>>> +#define container_of(ptr, type, member) ({??????????????? \
>>> +??? void *__mptr = (void *)(ptr);??????????????????? \
>>> +??? static_assert(__same_type(*(ptr), ((type *)0)->member)
||??? \
>>> +????????????? __same_type(*(ptr), void),??????????? \
>>> +????????????? "pointer type mismatch in
container_of()"); \
>>> +??? ((type *)(__mptr - offsetof(type, member))); })
>>> +
>>> +/**
>>> + * container_of_const - cast a member of a structure out to the
>>> containing
>>> + *??????????? structure and preserve the const-ness of the pointer
>>> + * @ptr:??????? the pointer to the member
>>> + * @type:??????? the type of the container struct this is embedded
in.
>>> + * @member:??????? the name of the member within the struct.
>>> + */
>>> +#define container_of_const(ptr, type, member) \
>>> +??? _Generic(ptr,??????????????????????????? \
>>> +??????? const typeof(*(ptr)) *: ((const type *)container_of(ptr,
>>> type, member)),\
>>> +??????? default: ((type *)container_of(ptr, type, member)) \
>>> +??? )
>>> +
>>> +#endif??? /* _LINUX_CONTAINER_OF_H */
>>
>> Please just do
>> #include "../../../include/linux/container_of.h"
>> instead.
> Okey, I'll do that.
>>
>>
>>> diff --git a/tools/virtio/linux/compiler.h
>>> b/tools/virtio/linux/compiler.h
>>> index 2c51bccb97bb..ac27b3ea6e67 100644
>>> --- a/tools/virtio/linux/compiler.h
>>> +++ b/tools/virtio/linux/compiler.h
>>> @@ -8,4 +8,7 @@
>>> ? #define READ_ONCE(var) (*((volatile typeof(var) *)(&(var))))
>>> ? ? #define __aligned(x) __attribute((__aligned__(x)))
>>> +
>>> +#define __same_type(a, b) __builtin_types_compatible_p(typeof(a),
>>> typeof(b))
>>> +
>>> ? #endif
>> #include "../../../include/linux/compiler_types.h" instead?
> I'll try it.
>>> diff --git a/tools/virtio/linux/kernel.h
b/tools/virtio/linux/kernel.h
>>> index 8b877167933d..3cd20cb92649 100644
>>> --- a/tools/virtio/linux/kernel.h
>>> +++ b/tools/virtio/linux/kernel.h
>>> @@ -10,6 +10,7 @@
>>> ? #include <stdarg.h>
>>> ? ? #include <linux/compiler.h>
>>> +#include <linux/container_of.h>
>>> ? #include <linux/log2.h>
>>> ? #include <linux/types.h>
>>> ? #include <linux/overflow.h>
>>> @@ -107,10 +108,6 @@ static inline void free_page(unsigned long
addr)
>>> ????? free((void *)addr);
>>> ? }
>>> ? -#define container_of(ptr, type, member) ({??????????? \
>>> -??? const typeof( ((type *)0)->member ) *__mptr = (ptr);??? \
>>> -??? (type *)( (char *)__mptr - offsetof(type,member) );})
>>> -
>>> ? # ifndef likely
>>> ? #? define likely(x)??? (__builtin_expect(!!(x), 1))
>>> ? # endif
>>> diff --git a/tools/virtio/linux/module.h
b/tools/virtio/linux/module.h
>>> index 9dfa96fea2b2..e2e791dbd104 100644
>>> --- a/tools/virtio/linux/module.h
>>> +++ b/tools/virtio/linux/module.h
>>> @@ -5,3 +5,4 @@
>>> ????? static __attribute__((unused)) const char
>>> *__MODULE_LICENSE_name = \
>>> ????????? __MODULE_LICENSE_value
>>> ? +struct device;
>>
>> It's not there in include/linux/module - pls put it in the
>> same here where it is for linux.
> I understood. I'll add some files that has the definition.

In vringh.c, 'struct device' is used in virtio_ring.h. Upon
investigating the preprocessed file, it was

discovered that 'struct device' is defined in bitmap.h, which is
included from architecture-specific headers.

On x86, the nesting includes

'linux/module.h' -> ... -> 'arch/x86/include/asm/msr.h'
->
'arch/x86/include/asm/cpumask.h' -> 'linux/cpumask.h' ->
'linux/bitmap.h'.

Could you advise on the appropriate way to include this file?

>>> --
>>> 2.25.1
>
> Best regards,
>
> Shunsuke.
>