Re: [PATCH 6/6] io_uring: add flag for allocating a fully sparse direct descriptor space

[Jens Axboe <axboe@kernel.dk>]

On 5/9/22 10:44 PM, Hao Xu wrote:
>> @@ -11931,6 +11937,9 @@ static int __io_uring_register(struct io_ring_ctx *ctx, unsigned opcode,
>>           ret = io_sqe_buffers_unregister(ctx);
>>           break;
>>       case IORING_REGISTER_FILES:
>> +        ret = -EFAULT;
>> +        if (!arg)
>> +            break;
>>           ret = io_sqe_files_register(ctx, arg, nr_args, NULL);
>>           break;
>>       case IORING_UNREGISTER_FILES:
>> diff --git a/include/uapi/linux/io_uring.h b/include/uapi/linux/io_uring.h
>> index b7f02a55032a..d09cf7c0d1fe 100644
>> --- a/include/uapi/linux/io_uring.h
>> +++ b/include/uapi/linux/io_uring.h
>> @@ -396,9 +396,15 @@ struct io_uring_files_update {
>>       __aligned_u64 /* __s32 * */ fds;
>>   };
>>   +/*
>> + * Register a fully sparse file sparse, rather than pass in an array of all
> 
>                                     ^space

Thanks, fixed.

>> + * -1 file descriptors.
>> + */
>> +#define IORING_RSRC_REGISTER_SPARSE    (1U << 0)
>> +
>>   struct io_uring_rsrc_register {
>>       __u32 nr;
>> -    __u32 resv;
>> +    __u32 flags;
>>       __u64 resv2;
>>       __aligned_u64 data;
>>       __aligned_u64 tags;
> 
> This looks promising, we may eliminate cqes for open/accept_direct reqs.
> 
> feel free to add,
> Reviewed-by: Hao Xu <howeyxu@tencent.com>

Added, thanks. Did you review the other ones too?

-- 
Jens Axboe