Hi Amir,
On 2019/11/19 上午11:14, Amir Goldstein wrote:
> On Tue, Nov 19, 2019 at 4:14 AM Jiufei Xue <jiufei.xue@xxxxxxxxxxxxxxxxx> wrote:
>>
>> This isn't cause any behavior changes and will be used by overlay
>> async IO implementation.
>>
>> Signed-off-by: Jiufei Xue <jiufei.xue@xxxxxxxxxxxxxxxxx>
>> ---
>> fs/read_write.c | 58 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
>> include/linux/fs.h | 16 +++++++++++++++
>> 2 files changed, 74 insertions(+)
>>
>> diff --git a/fs/read_write.c b/fs/read_write.c
>> index 5bbf587..3dfbcec 100644
>> --- a/fs/read_write.c
>> +++ b/fs/read_write.c
>> @@ -984,6 +984,64 @@ ssize_t vfs_iter_write(struct file *file, struct iov_iter *iter, loff_t *ppos,
>> }
>> EXPORT_SYMBOL(vfs_iter_write);
>>
>> +ssize_t vfs_iocb_iter_read(struct file *file, struct kiocb *iocb,
>> + struct iov_iter *iter)
>> +{
>> + ssize_t ret = 0;
>> + ssize_t tot_len;
>> +
>> + if (!file->f_op->read_iter)
>> + return -EINVAL;
>> + if (!(file->f_mode & FMODE_READ))
>> + return -EBADF;
>> + if (!(file->f_mode & FMODE_CAN_READ))
>> + return -EINVAL;
>> +
>> + tot_len = iov_iter_count(iter);
>> + if (!tot_len)
>> + return 0;
>> +
>> + ret = rw_verify_area(READ, file, &iocb->ki_pos, tot_len);
>> + if (ret < 0)
>> + return ret;
>> +
>> + ret = call_read_iter(file, iocb, iter);
>> + if (ret >= 0)
>> + fsnotify_access(file);
>> +
>> + return ret;
>> +}
>> +EXPORT_SYMBOL(vfs_iocb_iter_read);
>> +
>> +ssize_t vfs_iocb_iter_write(struct file *file, struct kiocb *iocb,
>> + struct iov_iter *iter)
>> +{
>> + ssize_t ret = 0;
>> + ssize_t tot_len;
>> +
>> + if (!file->f_op->write_iter)
>> + return -EINVAL;
>> + if (!(file->f_mode & FMODE_WRITE))
>> + return -EBADF;
>> + if (!(file->f_mode & FMODE_CAN_WRITE))
>> + return -EINVAL;
>> +
>> + tot_len = iov_iter_count(iter);
>> + if (!tot_len)
>> + return 0;
>> +
>> + ret = rw_verify_area(WRITE, file, &iocb->ki_pos, tot_len);
>> + if (ret < 0)
>> + return ret;
>> +
>> + ret = call_write_iter(file, iocb, iter);
>> + if (ret >= 0)
>> + fsnotify_modify(file);
>> +
>> + return ret;
>> +}
>> +EXPORT_SYMBOL(vfs_iocb_iter_write);
>> +
>
> If it was up to me, I would pass down an optional iocb pointer
> to the do_iter_XXX static helpers, instead of duplicating the code.
> Others may find your approach cleaner, so let's see what other
> people think.
>
Thanks for your review. I have considered your suggestion and
still think that adding new helpers are more clearly.
Let's wait for other people's opinions.
Thanks,
Jiufei
> Thanks,
> Amir.
>
