>On Sun, Feb 03 2013, majianpeng wrote:
>> Hi all,
>> When I wanted to do discard operations,but i set the openflag was
>> O_RDONLY,it returned a EBADF rather than EACCES or EPERM.
>> I searched the code and found:
>> >case BLKDISCARD:
>> >case BLKSECDISCARD: {
>> > uint64_t range[2];
>>
>> > if (!(mode & FMODE_WRITE))
>> > return -EBADF;
>> Initial i thought there was error.But i searched all code of kernel and
>> found some places like this.
>>
>> The description of EBADF is "Bad file numbe". There are some places where
>> returned EBADF like,
>> >if (!f.file)
>> > return -EBADF;
>>
>> So i think for checking file->f_mode when failed, it should return EACCESS.
>
>But that would break the ABI at this point. I agree with you, though,
>EBADF is not the right error for this case.
>
>--
>Jens Axboe
>
Sorry, can you explain in detail? Why can it break the ABI ?
Thanks!
Jianpeng Ma