sfc: Use fixed-size buffers for MCDI NVRAM requests

The low-level MCDI code always uses 32-bit MMIO operations, and
callers must pad input and output buffers to multiples of 4 bytes.
The MCDI NVRAM functions are not doing this.  Also, their buffers are
declared as variable-length arrays with no explicit maximum length.

Switch to a fixed buffer size based on the chunk size used by the
MTD driver (which is a multiple of 4).

Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 1 insertions, 0 deletions

diff --git a/drivers/net/sfc/mcdi.h b/drivers/net/sfc/mcdi.h
index de916728c2e3..10ce98f4c0fb 100644
--- a/drivers/net/sfc/mcdi.h
+++ b/drivers/net/sfc/mcdi.h
@@ -111,6 +111,7 @@ extern int efx_mcdi_nvram_read(struct efx_nic *efx, unsigned int type,
 extern int efx_mcdi_nvram_write(struct efx_nic *efx, unsigned int type,
                                 loff_t offset, const u8 *buffer,
                                 size_t length);
+#define EFX_MCDI_NVRAM_LEN_MAX 128
 extern int efx_mcdi_nvram_erase(struct efx_nic *efx, unsigned int type,
                                 loff_t offset, size_t length);
 extern int efx_mcdi_nvram_update_finish(struct efx_nic *efx,