sysctl: add proc_dointvec_ms_jiffies_minmax

add proc_dointvec_ms_jiffies_minmax to fit read msecs value to jiffies
with a limited range of values

Signed-off-by: Yuwei Wang <wangyuweihx@gmail.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

diff --git a/include/linux/sysctl.h b/include/linux/sysctl.h
index 80263f7..17b42ce 100644 (file)
--- a/include/linux/sysctl.h
+++ b/include/linux/sysctl.h
@@ -75,6 +75,8 @@ int proc_douintvec_minmax(struct ctl_table *table, int write, void *buffer,
 int proc_dou8vec_minmax(struct ctl_table *table, int write, void *buffer,
                        size_t *lenp, loff_t *ppos);
 int proc_dointvec_jiffies(struct ctl_table *, int, void *, size_t *, loff_t *);
+int proc_dointvec_ms_jiffies_minmax(struct ctl_table *table, int write,
+               void *buffer, size_t *lenp, loff_t *ppos);
 int proc_dointvec_userhz_jiffies(struct ctl_table *, int, void *, size_t *,
                loff_t *);
 int proc_dointvec_ms_jiffies(struct ctl_table *, int, void *, size_t *,

diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index e52b6e3..85c92e2 100644 (file)
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -1237,6 +1237,30 @@ static int do_proc_dointvec_ms_jiffies_conv(bool *negp, unsigned long *lvalp,
        return 0;
 }
 
+static int do_proc_dointvec_ms_jiffies_minmax_conv(bool *negp, unsigned long *lvalp,
+                                               int *valp, int write, void *data)
+{
+       int tmp, ret;
+       struct do_proc_dointvec_minmax_conv_param *param = data;
+       /*
+        * If writing, first do so via a temporary local int so we can
+        * bounds-check it before touching *valp.
+        */
+       int *ip = write ? &tmp : valp;
+
+       ret = do_proc_dointvec_ms_jiffies_conv(negp, lvalp, ip, write, data);
+       if (ret)
+               return ret;
+
+       if (write) {
+               if ((param->min && *param->min > tmp) ||
+                               (param->max && *param->max < tmp))
+                       return -EINVAL;
+               *valp = tmp;
+       }
+       return 0;
+}
+
 /**
  * proc_dointvec_jiffies - read a vector of integers as seconds
  * @table: the sysctl table
@@ -1259,6 +1283,17 @@ int proc_dointvec_jiffies(struct ctl_table *table, int write,
                            do_proc_dointvec_jiffies_conv,NULL);
 }
 
+int proc_dointvec_ms_jiffies_minmax(struct ctl_table *table, int write,
+                         void *buffer, size_t *lenp, loff_t *ppos)
+{
+       struct do_proc_dointvec_minmax_conv_param param = {
+               .min = (int *) table->extra1,
+               .max = (int *) table->extra2,
+       };
+       return do_proc_dointvec(table, write, buffer, lenp, ppos,
+                       do_proc_dointvec_ms_jiffies_minmax_conv, &param);
+}
+
 /**
  * proc_dointvec_userhz_jiffies - read a vector of integers as 1/USER_HZ seconds
  * @table: the sysctl table
@@ -1523,6 +1558,12 @@ int proc_dointvec_jiffies(struct ctl_table *table, int write,
        return -ENOSYS;
 }
 
+int proc_dointvec_ms_jiffies_minmax(struct ctl_table *table, int write,
+                                   void *buffer, size_t *lenp, loff_t *ppos)
+{
+       return -ENOSYS;
+}
+
 int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write,
                    void *buffer, size_t *lenp, loff_t *ppos)
 {