[RFC PATCH v1 27/57] net: e1000: Remove PAGE_SIZE compile-time constant assumption

[Ryan Roberts]

To prepare for supporting boot-time page size selection, refactor code
to remove assumptions about PAGE_SIZE being compile-time constant. Code
intended to be equivalent when compile-time page size is active.

Convert CPP conditionals to C conditionals. The compiler will dead code
strip when doing a compile-time page size build, for the same end
effect. But this will also work with boot-time page size builds.

Signed-off-by: Ryan Roberts <ryan.roberts@xxxxxxx>
---

***NOTE***
Any confused maintainers may want to read the cover note here for context:
https://lore.kernel.org/all/20241014105514.3206191-1-ryan.roberts@xxxxxxx/

 drivers/net/ethernet/intel/e1000/e1000_main.c | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/drivers/net/ethernet/intel/e1000/e1000_main.c b/drivers/net/ethernet/intel/e1000/e1000_main.c
index ab7ae418d2948..cc14788f5bb04 100644
--- a/drivers/net/ethernet/intel/e1000/e1000_main.c
+++ b/drivers/net/ethernet/intel/e1000/e1000_main.c
@@ -3553,12 +3553,10 @@ static int e1000_change_mtu(struct net_device *netdev, int new_mtu)
 
 	if (max_frame <= E1000_RXBUFFER_2048)
 		adapter->rx_buffer_len = E1000_RXBUFFER_2048;
-	else
-#if (PAGE_SIZE >= E1000_RXBUFFER_16384)
+	else if (PAGE_SIZE >= E1000_RXBUFFER_16384)
 		adapter->rx_buffer_len = E1000_RXBUFFER_16384;
-#elif (PAGE_SIZE >= E1000_RXBUFFER_4096)
+	else if (PAGE_SIZE >= E1000_RXBUFFER_4096)
 		adapter->rx_buffer_len = PAGE_SIZE;
-#endif
 
 	/* adjust allocation if LPE protects us, and we aren't using SBP */
 	if (!hw->tbi_compatibility_on &&
-- 
2.43.0