RDMA/hns: Use ib_umem_num_dma_blocks() instead of opencoding

mtr_umem_page_count() does the same thing, replace it with the core code.

Also, ib_umem_find_best_pgsz() should always be called to check that the
umem meets the page_size requirement. If there is a limited set of
page_sizes that work it the pgsz_bitmap should be set to that set. 0 is a
failure and the umem cannot be used.

Lightly tidy the control flow to implement this flow properly.

Link: https://lore.kernel.org/r/12-v2-270386b7e60b+28f4-umem_1_jgg@nvidia.com
Acked-by: Weihang Li <liweihang@huawei.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

diff --git a/drivers/infiniband/hw/hns/hns_roce_mr.c b/drivers/infiniband/hw/hns/hns_roce_mr.c
index 2628ba585d1f233e98ec249edd7663e35b74b89c..399295da37db9d5a84589009df6a899f2c91d427 100644 (file)
--- a/drivers/infiniband/hw/hns/hns_roce_mr.c
+++ b/drivers/infiniband/hw/hns/hns_roce_mr.c
@@ -707,19 +707,6 @@ static inline size_t mtr_bufs_size(struct hns_roce_buf_attr *attr)
        return size;
 }
 
-static inline int mtr_umem_page_count(struct ib_umem *umem,
-                                     unsigned int page_shift)
-{
-       int count = ib_umem_page_count(umem);
-
-       if (page_shift >= PAGE_SHIFT)
-               count >>= page_shift - PAGE_SHIFT;
-       else
-               count <<= PAGE_SHIFT - page_shift;
-
-       return count;
-}
-
 static inline size_t mtr_kmem_direct_size(bool is_direct, size_t alloc_size,
                                          unsigned int page_shift)
 {
@@ -767,12 +754,10 @@ static int mtr_alloc_bufs(struct hns_roce_dev *hr_dev, struct hns_roce_mtr *mtr,
                          struct ib_udata *udata, unsigned long user_addr)
 {
        struct ib_device *ibdev = &hr_dev->ib_dev;
-       unsigned int max_pg_shift = buf_attr->page_shift;
-       unsigned int best_pg_shift = 0;
+       unsigned int best_pg_shift;
        int all_pg_count = 0;
        size_t direct_size;
        size_t total_size;
-       unsigned long tmp;
        int ret;
 
        total_size = mtr_bufs_size(buf_attr);
@@ -782,6 +767,9 @@ static int mtr_alloc_bufs(struct hns_roce_dev *hr_dev, struct hns_roce_mtr *mtr,
        }
 
        if (udata) {
+               unsigned long pgsz_bitmap;
+               unsigned long page_size;
+
                mtr->kmem = NULL;
                mtr->umem = ib_umem_get(ibdev, user_addr, total_size,
                                        buf_attr->user_access);
@@ -790,15 +778,17 @@ static int mtr_alloc_bufs(struct hns_roce_dev *hr_dev, struct hns_roce_mtr *mtr,
                                  PTR_ERR(mtr->umem));
                        return -ENOMEM;
                }
-               if (buf_attr->fixed_page) {
-                       best_pg_shift = max_pg_shift;
-               } else {
-                       tmp = GENMASK(max_pg_shift, 0);
-                       ret = ib_umem_find_best_pgsz(mtr->umem, tmp, user_addr);
-                       best_pg_shift = (ret <= PAGE_SIZE) ?
-                                       PAGE_SHIFT : ilog2(ret);
-               }
-               all_pg_count = mtr_umem_page_count(mtr->umem, best_pg_shift);
+               if (buf_attr->fixed_page)
+                       pgsz_bitmap = 1 << buf_attr->page_shift;
+               else
+                       pgsz_bitmap = GENMASK(buf_attr->page_shift, PAGE_SHIFT);
+
+               page_size = ib_umem_find_best_pgsz(mtr->umem, pgsz_bitmap,
+                                                  user_addr);
+               if (!page_size)
+                       return -EINVAL;
+               best_pg_shift = order_base_2(page_size);
+               all_pg_count = ib_umem_num_dma_blocks(mtr->umem, page_size);
                ret = 0;
        } else {
                mtr->umem = NULL;
@@ -808,16 +798,15 @@ static int mtr_alloc_bufs(struct hns_roce_dev *hr_dev, struct hns_roce_mtr *mtr,
                        return -ENOMEM;
                }
                direct_size = mtr_kmem_direct_size(is_direct, total_size,
-                                                  max_pg_shift);
+                                                  buf_attr->page_shift);
                ret = hns_roce_buf_alloc(hr_dev, total_size, direct_size,
-                                        mtr->kmem, max_pg_shift);
+                                        mtr->kmem, buf_attr->page_shift);
                if (ret) {
                        ibdev_err(ibdev, "Failed to alloc kmem, ret %d\n", ret);
                        goto err_alloc_mem;
-               } else {
-                       best_pg_shift = max_pg_shift;
-                       all_pg_count = mtr->kmem->npages;
                }
+               best_pg_shift = buf_attr->page_shift;
+               all_pg_count = mtr->kmem->npages;
        }
 
        /* must bigger than minimum hardware page shift */