RDMA/i40iw: Use ib_umem_num_dma_pages()

If ib_umem_find_best_pgsz() returns > PAGE_SIZE then the equation here is
not correct. 'start' should be 'virt'. Change it to use the core code for
page_num and the canonical calculation of page_shift.

Fixes: eb52c0333f06 ("RDMA/i40iw: Use core helpers to get aligned DMA address within a supported page size")
Link: https://lore.kernel.org/r/8-v2-270386b7e60b+28f4-umem_1_jgg@nvidia.com
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

diff --git a/drivers/infiniband/hw/i40iw/i40iw_verbs.c b/drivers/infiniband/hw/i40iw/i40iw_verbs.c
index a9278ef..4511e17 100644 (file)
--- a/drivers/infiniband/hw/i40iw/i40iw_verbs.c
+++ b/drivers/infiniband/hw/i40iw/i40iw_verbs.c
@@ -1745,15 +1745,12 @@ static struct ib_mr *i40iw_reg_user_mr(struct ib_pd *pd,
        struct i40iw_mr *iwmr;
        struct ib_umem *region;
        struct i40iw_mem_reg_req req;
-       u64 pbl_depth = 0;
        u32 stag = 0;
        u16 access;
-       u64 region_length;
        bool use_pbles = false;
        unsigned long flags;
        int err = -ENOSYS;
        int ret;
-       int pg_shift;
 
        if (!udata)
                return ERR_PTR(-EOPNOTSUPP);
@@ -1788,18 +1785,13 @@ static struct ib_mr *i40iw_reg_user_mr(struct ib_pd *pd,
        if (req.reg_type == IW_MEMREG_TYPE_MEM)
                iwmr->page_size = ib_umem_find_best_pgsz(region, SZ_4K | SZ_2M,
                                                         virt);
-
-       region_length = region->length + (start & (iwmr->page_size - 1));
-       pg_shift = ffs(iwmr->page_size) - 1;
-       pbl_depth = region_length >> pg_shift;
-       pbl_depth += (region_length & (iwmr->page_size - 1)) ? 1 : 0;
        iwmr->length = region->length;
 
        iwpbl->user_base = virt;
        palloc = &iwpbl->pble_alloc;
 
        iwmr->type = req.reg_type;
-       iwmr->page_cnt = (u32)pbl_depth;
+       iwmr->page_cnt = ib_umem_num_dma_blocks(region, iwmr->page_size);
 
        switch (req.reg_type) {
        case IW_MEMREG_TYPE_QP: