On 23/03/2021 13:30, Christoph Hellwig wrote:
> On Tue, Mar 23, 2021 at 08:06:56PM +0900, Johannes Thumshirn wrote:
>> diff --git a/block/bio.c b/block/bio.c
>> index 26b7f721cda8..215fe24a01ee 100644
>> --- a/block/bio.c
>> +++ b/block/bio.c
>> @@ -1094,8 +1094,14 @@ int bio_iov_iter_get_pages(struct bio *bio, struct iov_iter *iter)
>> int ret = 0;
>>
>> if (iov_iter_is_bvec(iter)) {
>> - if (WARN_ON_ONCE(bio_op(bio) == REQ_OP_ZONE_APPEND))
>> - return -EINVAL;
>> + if (bio_op(bio) == REQ_OP_ZONE_APPEND) {
>> + struct request_queue *q = bio->bi_bdev->bd_disk->queue;
>> + unsigned int max_append =
>> + queue_max_zone_append_sectors(q) << 9;
>> +
>> + if (WARN_ON_ONCE(iter->count > max_append))
>> + return -EINVAL;
>> + }
>
> That is not correct. bio_iov_iter_get_pages just fills the bio as far
> as we can, and then returns 0 for the next call to continue. Basically
> what you want here is a partial version of bio_iov_bvec_set.
>
Isn't that what I did? The above is checking if we have REQ_OP_ZONE_APPEND and
then returns EINVAL if iter->count is bigger than queue_max_zone_append_sectors().
If the check doesn't fail, its going to call bio_iov_bvec_set().
