@@ -56,8 +56,17 @@ static inline bool rdma_rw_io_needs_mr(struct ib_device *dev, u8 port_num,
return false;
}
-static inline u32 rdma_rw_fr_page_list_len(struct ib_device *dev,
- bool pi_support)
+/**
+ * rdma_rw_fr_page_list_len - return the max number of pages mapped by 1 MR
+ * @dev: RDMA device that will eventually create a PD for needed MRs
+ * @pi_support: Whether MRs will be created for protection information offload
+ *
+ * Returns the number of pages that one MR can map for RDMA operation by the
+ * given device. One can determine the maximal data size according to the
+ * result of this function, or chose using multiple MRs for the RDMA operation
+ * as well.
+ */
+u32 rdma_rw_fr_page_list_len(struct ib_device *dev, bool pi_support)
{
u32 max_pages;
@@ -69,6 +78,7 @@ static inline u32 rdma_rw_fr_page_list_len(struct ib_device *dev,
/* arbitrary limit to avoid allocating gigantic resources */
return min_t(u32, max_pages, 256);
}
+EXPORT_SYMBOL(rdma_rw_fr_page_list_len);
static inline int rdma_rw_inv_key(struct rdma_rw_reg_ctx *reg)
{
@@ -69,5 +69,6 @@ unsigned int rdma_rw_mr_factor(struct ib_device *device, u8 port_num,
void rdma_rw_init_qp(struct ib_device *dev, struct ib_qp_init_attr *attr);
int rdma_rw_init_mrs(struct ib_qp *qp, struct ib_qp_init_attr *attr);
void rdma_rw_cleanup_mrs(struct ib_qp *qp);
+u32 rdma_rw_fr_page_list_len(struct ib_device *dev, bool pi_support);
#endif /* _RDMA_RW_H */
ULP's will use this information to determine the maximal data transfer size per IO operation. Signed-off-by: Max Gurtovoy <maxg@mellanox.com> --- drivers/infiniband/core/rw.c | 14 ++++++++++++-- include/rdma/rw.h | 1 + 2 files changed, 13 insertions(+), 2 deletions(-)