On 6/6/2025 2:42 PM, David Hildenbrand wrote:
> On 05.06.25 17:37, Fuad Tabba wrote:
>> This patch enables support for shared memory in guest_memfd, including
>> mapping that memory from host userspace.
>>
>> This functionality is gated by the KVM_GMEM_SHARED_MEM Kconfig option,
>> and enabled for a given instance by the GUEST_MEMFD_FLAG_SUPPORT_SHARED
>> flag at creation time.
>>
>> Co-developed-by: Ackerley Tng <ackerleytng@xxxxxxxxxx>
>> Signed-off-by: Ackerley Tng <ackerleytng@xxxxxxxxxx>
>> Signed-off-by: Fuad Tabba <tabba@xxxxxxxxxx>
>> ---
>
> [...]
>
>> +static bool kvm_gmem_supports_shared(struct inode *inode)
>> +{
>> + u64 flags;
>> +
>> + if (!IS_ENABLED(CONFIG_KVM_GMEM_SHARED_MEM))
>> + return false;
>> +
>> + flags = (u64)inode->i_private;
>
> Can probably do above
>
> const u64 flags = (u64)inode->i_private;
>
>> +
>> + return flags & GUEST_MEMFD_FLAG_SUPPORT_SHARED;
>> +}
>> +
I agree on using const will have some safety, clarity and optimization.
I did not understand why don't we directly check the flags like...
return (u64)inode->i_private & GUEST_MEMFD_FLAG_SUPPORT_SHARED;
...which is more concise.
Thanks,
Shivank
