seq_file: constify seq_operations

Make all seq_operations structs const, to help mitigate against
revectoring user-triggerable function pointers.

This is derived from the grsecurity patch, although generated from scratch
because it's simpler than extracting the changes from there.

Signed-off-by: James Morris <jmorris@namei.org>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Acked-by: Casey Schaufler <casey@schaufler-ca.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/scsi/sg.c b/drivers/scsi/sg.c
index 4968c4c..848b594 100644
--- a/drivers/scsi/sg.c
+++ b/drivers/scsi/sg.c
@@ -2233,7 +2233,7 @@
 	.open = sg_proc_open_dev,
 	.release = seq_release,
 };
-static struct seq_operations dev_seq_ops = {
+static const struct seq_operations dev_seq_ops = {
 	.start = dev_seq_start,
 	.next  = dev_seq_next,
 	.stop  = dev_seq_stop,
@@ -2246,7 +2246,7 @@
 	.open = sg_proc_open_devstrs,
 	.release = seq_release,
 };
-static struct seq_operations devstrs_seq_ops = {
+static const struct seq_operations devstrs_seq_ops = {
 	.start = dev_seq_start,
 	.next  = dev_seq_next,
 	.stop  = dev_seq_stop,
@@ -2259,7 +2259,7 @@
 	.open = sg_proc_open_debug,
 	.release = seq_release,
 };
-static struct seq_operations debug_seq_ops = {
+static const struct seq_operations debug_seq_ops = {
 	.start = dev_seq_start,
 	.next  = dev_seq_next,
 	.stop  = dev_seq_stop,