mlx5_core: Copy DIF fields only when input and output space values match

Some DIF implementations (SCSI initiator/target) may want to use different
input/output values for application tag and/or reference tag. So in
case memory/wire domain values don't match HW must not copy them.

Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

diff --git a/drivers/infiniband/hw/mlx5/qp.c b/drivers/infiniband/hw/mlx5/qp.c
index 00b5563..a89f704 100644 (file)
--- a/drivers/infiniband/hw/mlx5/qp.c
+++ b/drivers/infiniband/hw/mlx5/qp.c
@@ -2078,6 +2078,7 @@ static int mlx5_set_bsf(struct ib_mr *sig_mr,
        struct ib_sig_domain *wire = &sig_attrs->wire;
        int ret, selector;
 
+       memset(bsf, 0, sizeof(*bsf));
        switch (sig_attrs->mem.sig_type) {
        case IB_SIG_TYPE_T10_DIF:
                if (sig_attrs->wire.sig_type != IB_SIG_TYPE_T10_DIF)
@@ -2090,9 +2091,11 @@ static int mlx5_set_bsf(struct ib_mr *sig_mr,
                        /* Same block structure */
                        basic->bsf_size_sbs = 1 << 4;
                        if (mem->sig.dif.bg_type == wire->sig.dif.bg_type)
-                               basic->wire.copy_byte_mask = 0xff;
-                       else
-                               basic->wire.copy_byte_mask = 0x3f;
+                               basic->wire.copy_byte_mask |= 0xc0;
+                       if (mem->sig.dif.app_tag == wire->sig.dif.app_tag)
+                               basic->wire.copy_byte_mask |= 0x30;
+                       if (mem->sig.dif.ref_tag == wire->sig.dif.ref_tag)
+                               basic->wire.copy_byte_mask |= 0x0f;
                } else
                        basic->wire.bs_selector = bs_selector(wire->sig.dif.pi_interval);