sysctl: Allow custom converters from outside sysctl

The new non-static proc_dointvec_conv forwards a custom converter
function to do_proc_dointvec from outside the sysctl scope. Rename the
do_proc_dointvec call points so any future changes to proc_dointvec_conv
are propagated in sysctl.c This is a preparation commit that allows the
integer jiffie converter functions to move out of kernel/sysctl.c.

Signed-off-by: Joel Granados <[e-mail]>

include/linux/sysctl.h

···
 int proc_dobool(const struct ctl_table *table, int write, void *buffer,
 		size_t *lenp, loff_t *ppos);
 int proc_dointvec(const struct ctl_table *, int, void *, size_t *, loff_t *);
+int proc_dointvec_conv(const struct ctl_table *table, int dir, void *buffer,
+		       size_t *lenp, loff_t *ppos,
+		       int (*conv)(bool *negp, unsigned long *u_ptr, int *k_ptr,
+				   int dir, const struct ctl_table *table));
 int proc_douintvec(const struct ctl_table *, int, void *, size_t *, loff_t *);
 int proc_dointvec_minmax(const struct ctl_table *, int, void *, size_t *, loff_t *);
 int proc_douintvec_minmax(const struct ctl_table *table, int write, void *buffer,

kernel/sysctl.c

···
 					 lenp, ppos, HZ, 1000l);
 }
 
+int proc_dointvec_conv(const struct ctl_table *table, int dir, void *buffer,
+		       size_t *lenp, loff_t *ppos,
+		       int (*conv)(bool *negp, unsigned long *u_ptr, int *k_ptr,
+				   int dir, const struct ctl_table *table))
+{
+	return do_proc_dointvec(table, dir, buffer, lenp, ppos, conv);
+}
+
 /**
  * proc_dointvec_jiffies - read a vector of integers as seconds
  * @table: the sysctl table
···
 int proc_dointvec_jiffies(const struct ctl_table *table, int dir,
 			  void *buffer, size_t *lenp, loff_t *ppos)
 {
-	return do_proc_dointvec(table, dir, buffer, lenp, ppos,
-				do_proc_int_conv_jiffies);
+	return proc_dointvec_conv(table, dir, buffer, lenp, ppos,
+				  do_proc_int_conv_jiffies);
 }
 
 int proc_dointvec_ms_jiffies_minmax(const struct ctl_table *table, int dir,
 			  void *buffer, size_t *lenp, loff_t *ppos)
 {
-	return do_proc_dointvec(table, dir, buffer, lenp, ppos,
-			do_proc_int_conv_ms_jiffies_minmax);
+	return proc_dointvec_conv(table, dir, buffer, lenp, ppos,
+				  do_proc_int_conv_ms_jiffies_minmax);
 }
 
 /**
···
 {
 	if (SYSCTL_USER_TO_KERN(dir) && USER_HZ < HZ)
 		return -EINVAL;
-	return do_proc_dointvec(table, dir, buffer, lenp, ppos,
-				do_proc_int_conv_userhz_jiffies);
+	return proc_dointvec_conv(table, dir, buffer, lenp, ppos,
+				  do_proc_int_conv_userhz_jiffies);
 }
 
 /**
···
 int proc_dointvec_ms_jiffies(const struct ctl_table *table, int dir, void *buffer,
 		size_t *lenp, loff_t *ppos)
 {
-	return do_proc_dointvec(table, dir, buffer, lenp, ppos,
-				do_proc_int_conv_ms_jiffies);
+	return proc_dointvec_conv(table, dir, buffer, lenp, ppos,
+				  do_proc_int_conv_ms_jiffies);
 }
 
 /**
···
 
 int proc_doulongvec_ms_jiffies_minmax(const struct ctl_table *table, int dir,
 				      void *buffer, size_t *lenp, loff_t *ppos)
+{
+	return -ENOSYS;
+}
+
+int proc_dointvec_conv(const struct ctl_table *table, int dir, void *buffer,
+		       size_t *lenp, loff_t *ppos,
+		       int (*conv)(bool *negp, unsigned long *u_ptr, int *k_ptr,
+				   int dir, const struct ctl_table *table))
 {
 	return -ENOSYS;
 }