On 27/10/2023 16:17, Zhu Yanjun wrote:
> 在 2023/10/27 13:41, Li Zhijian 写道:
>> mr->page_list only encodes *page without page offset, when
>> page_size != PAGE_SIZE, we cannot restore the address with a wrong
>> page_offset.
>>
>> Note that this patch will break some ULPs that try to register 4K
>> MR when PAGE_SIZE is not 4K.
>> SRP and nvme over RXE is known to be impacted.
>
> When ULP uses folio or compound page, ULP can not work well with RXE after this commit is applied.
>
> Perhaps removing page_size set in RXE is a good solution because page_size is set twice, firstly page_size is set in infiniband/core, secondly it is set in RXE.
Does The RXE one mean rxe_mr_init(), I think rxe_reg_user_mr() requires this.
48 static void rxe_mr_init(int access, struct rxe_mr *mr)
49 {
50 u32 key = mr->elem.index << 8 | rxe_get_next_key(-1);
51
52 /* set ibmr->l/rkey and also copy into private l/rkey
53 * for user MRs these will always be the same
54 * for cases where caller 'owns' the key portion
55 * they may be different until REG_MR WQE is executed.
56 */
57 mr->lkey = mr->ibmr.lkey = key;
58 mr->rkey = mr->ibmr.rkey = key;
59
60 mr->access = access;
61 mr->ibmr.page_size = PAGE_SIZE;
62 mr->page_mask = PAGE_MASK;
63 mr->page_shift = PAGE_SHIFT;
64 mr->state = RXE_MR_STATE_INVALID;
65 }
Thanks
Zhijian
>
> When folio or compound page is used in ULP, it is very possible that page_size in infiniband/core is different from the page_size in RXE
>
> Not sure what problem this difference will cause.
>
> Zhu Yanjun
>
>>
>> Signed-off-by: Li Zhijian <lizhijian@xxxxxxxxxxx>
>> ---
>> drivers/infiniband/sw/rxe/rxe_mr.c | 6 ++++++
>> 1 file changed, 6 insertions(+)
>>
>> diff --git a/drivers/infiniband/sw/rxe/rxe_mr.c b/drivers/infiniband/sw/rxe/rxe_mr.c
>> index f54042e9aeb2..61a136ea1d91 100644
>> --- a/drivers/infiniband/sw/rxe/rxe_mr.c
>> +++ b/drivers/infiniband/sw/rxe/rxe_mr.c
>> @@ -234,6 +234,12 @@ int rxe_map_mr_sg(struct ib_mr *ibmr, struct scatterlist *sgl,
>> struct rxe_mr *mr = to_rmr(ibmr);
>> unsigned int page_size = mr_page_size(mr);
>> + if (page_size != PAGE_SIZE) {
>> + rxe_info_mr(mr, "Unsupported MR with page_size %u, expect %lu\n",
>> + page_size, PAGE_SIZE);
>> + return -EOPNOTSUPP;
>> + }
>> +
>> mr->nbuf = 0;
>> mr->page_shift = ilog2(page_size);
>> mr->page_mask = ~((u64)page_size - 1);
>
