net/mlx5: Add MLX5_ARRAY_SET64 to fix BUILD_BUG_ON
authorTom Herbert <tom@herbertland.com>
Wed, 12 Oct 2016 01:57:10 +0000 (04:57 +0300)
committerDavid S. Miller <davem@davemloft.net>
Thu, 13 Oct 2016 14:13:24 +0000 (10:13 -0400)
I am hitting this in mlx5:

drivers/net/ethernet/mellanox/mlx5/core/pagealloc.c: In function
reclaim_pages_cmd.clone.0:
drivers/net/ethernet/mellanox/mlx5/core/pagealloc.c:346: error: call
to __compiletime_assert_346 declared with attribute error:
BUILD_BUG_ON failed: __mlx5_bit_off(manage_pages_out, pas[i]) % 64
drivers/net/ethernet/mellanox/mlx5/core/pagealloc.c: In function give_pages:
drivers/net/ethernet/mellanox/mlx5/core/pagealloc.c:291: error: call
to __compiletime_assert_291 declared with attribute error:
BUILD_BUG_ON failed: __mlx5_bit_off(manage_pages_in, pas[i]) % 64

Problem is that this is doing a BUILD_BUG_ON on a non-constant
expression because of trying to take offset of pas[i] in the
structure.

Fix is to create MLX5_ARRAY_SET64 that takes an additional argument
that is the field index to separate between BUILD_BUG_ON on the array
constant field and the indexed field to assign the value to.
There are two callers of MLX5_SET64 that are trying to get a variable
offset, change those to call MLX5_ARRAY_SET64 passing 'pas' and 'i'
as the arguments to use in the offset check and the indexed value
assignment.

Fixes: a533ed5e179cd ("net/mlx5: Pages management commands via mlx5 ifc")
Signed-off-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
drivers/net/ethernet/mellanox/mlx5/core/pagealloc.c
include/linux/mlx5/device.h

index d4585154151db43ce1df6ef97312a41296bd39d9..cc4fd61914d30b567d962f24f15bfea3bb1da92c 100644 (file)
@@ -287,7 +287,7 @@ retry:
 
                        goto retry;
                }
-               MLX5_SET64(manage_pages_in, in, pas[i], addr);
+               MLX5_ARRAY_SET64(manage_pages_in, in, pas, i, addr);
        }
 
        MLX5_SET(manage_pages_in, in, opcode, MLX5_CMD_OP_MANAGE_PAGES);
@@ -344,7 +344,7 @@ static int reclaim_pages_cmd(struct mlx5_core_dev *dev,
                if (fwp->func_id != func_id)
                        continue;
 
-               MLX5_SET64(manage_pages_out, out, pas[i], fwp->addr);
+               MLX5_ARRAY_SET64(manage_pages_out, out, pas, i, fwp->addr);
                i++;
        }
 
index 77c141797152ef80af0a9e2d0070bfc56e796f27..58276144ba81f338ae82f8d3ab960c7dff9d58e3 100644 (file)
@@ -92,12 +92,21 @@ __mlx5_mask(typ, fld))
        ___t; \
 })
 
-#define MLX5_SET64(typ, p, fld, v) do { \
+#define __MLX5_SET64(typ, p, fld, v) do { \
        BUILD_BUG_ON(__mlx5_bit_sz(typ, fld) != 64); \
-       BUILD_BUG_ON(__mlx5_bit_off(typ, fld) % 64); \
        *((__be64 *)(p) + __mlx5_64_off(typ, fld)) = cpu_to_be64(v); \
 } while (0)
 
+#define MLX5_SET64(typ, p, fld, v) do { \
+       BUILD_BUG_ON(__mlx5_bit_off(typ, fld) % 64); \
+       __MLX5_SET64(typ, p, fld, v); \
+} while (0)
+
+#define MLX5_ARRAY_SET64(typ, p, fld, idx, v) do { \
+       BUILD_BUG_ON(__mlx5_bit_off(typ, fld) % 64); \
+       __MLX5_SET64(typ, p, fld[idx], v); \
+} while (0)
+
 #define MLX5_GET64(typ, p, fld) be64_to_cpu(*((__be64 *)(p) + __mlx5_64_off(typ, fld)))
 
 #define MLX5_GET64_PR(typ, p, fld) ({ \