[PATCH 3/3] drivers: libata: add sysctl: 'libata.allow_tpm' for self-encrypted devices

[Enrico Weigelt, metux IT consult]

libata tpm functionality, needed for self encrypted devices (OPAL, ...),
is currently disabled per default and needs to be enabled via kernel
command line.

This patch allows enabling it via sysctl.

The implementation might look a bit 'naive', as there aren't any locks
or barriers, etc. As we're dealing just w/ a plain boolean value, that's
only checked when an tpm-related ioctl is called, we're fine w/ that.

Signed-off-by: Enrico Weigelt, metux IT consult <info@xxxxxxxxx>
---
 drivers/ata/libata-core.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
index d3044c9..80ba844 100644
--- a/drivers/ata/libata-core.c
+++ b/drivers/ata/libata-core.c
@@ -177,6 +177,13 @@ struct ata_force_ent {
 MODULE_VERSION(DRV_VERSION);
 
 static struct ctl_table ctl_libata[] = {
+	{
+		.procname	= "allow_tpm",
+		.data		= &libata_allow_tpm,
+		.maxlen		= sizeof(libata_allow_tpm),
+		.mode		= 0644,
+		.proc_handler	= proc_dointvec,
+	},
 	{}
 };
 
-- 
1.9.1