[PATCH] be2net: fix adapter->big_page_size miscaculation

From: Qian Cai
Date: Fri Jul 12 2019 - 15:23:59 EST


The commit d66acc39c7ce ("bitops: Optimise get_order()") introduced a
problem for the be2net driver as "rx_frag_size" could be a module
parameter that can be changed while loading the module. That commit
checks __builtin_constant_p() first in get_order() which cause
"adapter->big_page_size" to be assigned a value based on the
the default "rx_frag_size" value at the compilation time. It also
generate a compilation warning,

In file included from ./arch/powerpc/include/asm/page_64.h:107,
from ./arch/powerpc/include/asm/page.h:242,
from ./arch/powerpc/include/asm/mmu.h:132,
from ./arch/powerpc/include/asm/lppaca.h:47,
from ./arch/powerpc/include/asm/paca.h:17,
from ./arch/powerpc/include/asm/current.h:13,
from ./include/linux/thread_info.h:21,
from ./arch/powerpc/include/asm/processor.h:39,
from ./include/linux/prefetch.h:15,
from drivers/net/ethernet/emulex/benet/be_main.c:14:
drivers/net/ethernet/emulex/benet/be_main.c: In function
'be_rx_cqs_create':
./include/asm-generic/getorder.h:54:9: warning: comparison is always
true due to limited range of data type [-Wtype-limits]
(((n) < (1UL << PAGE_SHIFT)) ? 0 : \
^
drivers/net/ethernet/emulex/benet/be_main.c:3138:33: note: in expansion
of macro 'get_order'
adapter->big_page_size = (1 << get_order(rx_frag_size)) * PAGE_SIZE;
^~~~~~~~~

Fix it by using __get_order() instead which will calculate in runtime.

Fixes: d66acc39c7ce ("bitops: Optimise get_order()")
Signed-off-by: Qian Cai <cai@xxxxxx>
---
drivers/net/ethernet/emulex/benet/be_main.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/emulex/benet/be_main.c b/drivers/net/ethernet/emulex/benet/be_main.c
index 82015c8a5ed7..db13e714df7c 100644
--- a/drivers/net/ethernet/emulex/benet/be_main.c
+++ b/drivers/net/ethernet/emulex/benet/be_main.c
@@ -3135,7 +3135,7 @@ static int be_rx_cqs_create(struct be_adapter *adapter)
if (adapter->num_rx_qs == 0)
adapter->num_rx_qs = 1;

- adapter->big_page_size = (1 << get_order(rx_frag_size)) * PAGE_SIZE;
+ adapter->big_page_size = (1 << __get_order(rx_frag_size)) * PAGE_SIZE;
for_all_rx_queues(adapter, rxo, i) {
rxo->adapter = adapter;
cq = &rxo->cq;
--
1.8.3.1