[PATCH 1/2] ata: allow toggling fua parameter at runtime

[Maciej S. Szmigiero]

From: "Maciej S. Szmigiero" <maciej.szmigiero@xxxxxxxxxx>

Currently, the libata.fua parameter isn't runtime-writable, so a
system restart is required in order to toggle it.
This unnecessarily complicates testing how drives behave with FUA on and
off.

Let's make this parameter R/W instead, like many others in the kernel.

Example usage:
Disable the parameter:
echo 0 >/sys/module/libata/parameters/fua

Revalidate disk cache settings:
F=/sys/class/scsi_disk/0\:0\:0\:0/cache_type; echo `cat $F` >$F

Signed-off-by: Maciej S. Szmigiero <maciej.szmigiero@xxxxxxxxxx>
---
 drivers/ata/libata-core.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
index 75b86913db1ac..b322006c85806 100644
--- a/drivers/ata/libata-core.c
+++ b/drivers/ata/libata-core.c
@@ -128,7 +128,7 @@ module_param(atapi_passthru16, int, 0444);
 MODULE_PARM_DESC(atapi_passthru16, "Enable ATA_16 passthru for ATAPI devices (0=off, 1=on [default])");
 
 int libata_fua = 0;
-module_param_named(fua, libata_fua, int, 0444);
+module_param_named(fua, libata_fua, int, 0644);
 MODULE_PARM_DESC(fua, "FUA support (0=off [default], 1=on)");
 
 static int ata_ignore_hpa;