在 2023/10/30 20:40, Jason Gunthorpe 写道:
On Mon, Oct 30, 2023 at 07:51:41AM +0000, Zhijian Li (Fujitsu) wrote:
On 27/10/2023 13:41, Li Zhijian wrote:
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.
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) {
It seems this condition is too strict, it should be:
if (!IS_ALIGNED(page_size, PAGE_SIZE))
So that, page_size with (N * PAGE_SIZE) can work as previously.
Because the offset(mr.iova & page_mask) will get lost only when !IS_ALIGNED(page_size, PAGE_SIZE)
That makes sense
I read all the discussions very carefully.
Thanks, Greg.
Because RXE only supports PAGE_SIZE, when CONFIG_ARM64_64K_PAGES is
enabled, the PAGE_SIZE is 64K, when CONFIG_ARM64_64K_PAGES is disabled,
PAGE_SIZE is 4K.
But NVMe calls ib_map_mr_sg with a fixed size SZ_4K. When
CONFIG_ARM64_64K_PAGES is enabled, it is still 4K. This is not a problem
in RXE. This problem is in NVMe.
If this problem in NVMe is not fixed, NVMe still can not use RXE to make
tests with blktests when CONFIG_ARM64_64K_PAGES is enabled.
This is not a problem in RXE, it should not be fixed in RXE.
Zhu Yanjun
Jason
