sysctl: Create unsigned int converter using new macro

Pass sysctl_{user_to_kern,kern_to_user}_uint_conv (unsigned integer
uni-directional converters) to the new SYSCTL_UINT_CONV_CUSTOM macro
to create do_proc_douintvec_conv's replacement (do_proc_uint_conv).

This is a preparation commit to use the unsigned integer converter from
outside sysctl. No functional change is intended.

Signed-off-by: Joel Granados <joel.granados@kernel.org>

diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index df96d3355dfc2035bc0bc687b3c35eed6418c396..fb4f4ec99811d175da6b6ccfa975c8abad4462e7 100644 (file)
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -462,23 +462,36 @@ static SYSCTL_INT_CONV_CUSTOM(_ms_jiffies_minmax,
                              sysctl_user_to_kern_int_conv_ms,
                              sysctl_kern_to_user_int_conv_ms, true)
 
-static int do_proc_douintvec_conv(unsigned long *u_ptr,
-                                 unsigned int *k_ptr, int dir,
-                                 const struct ctl_table *table)
+#define SYSCTL_UINT_CONV_CUSTOM(name, user_to_kern, kern_to_user)      \
+int do_proc_uint_conv##name(unsigned long *u_ptr, unsigned int *k_ptr, \
+                          int dir, const struct ctl_table *tbl)        \
+{                                                                      \
+       if (SYSCTL_USER_TO_KERN(dir))                                   \
+               return user_to_kern(u_ptr, k_ptr);                      \
+       return kern_to_user(u_ptr, k_ptr);                              \
+}
+
+static int sysctl_user_to_kern_uint_conv(const unsigned long *u_ptr,
+                                        unsigned int *k_ptr)
 {
-       if (SYSCTL_USER_TO_KERN(dir)) {
-               if (*u_ptr > UINT_MAX)
-                       return -EINVAL;
-               WRITE_ONCE(*k_ptr, *u_ptr);
-       } else {
-               unsigned int val = READ_ONCE(*k_ptr);
-               *u_ptr = (unsigned long)val;
-       }
+       if (*u_ptr > UINT_MAX)
+               return -EINVAL;
+       WRITE_ONCE(*k_ptr, *u_ptr);
        return 0;
 }
 
-static const char proc_wspace_sep[] = { ' ', '\t', '\n' };
+static int sysctl_kern_to_user_uint_conv(unsigned long *u_ptr,
+                                        const unsigned int *k_ptr)
+{
+       unsigned int val = READ_ONCE(*k_ptr);
+       *u_ptr = (unsigned long)val;
+       return 0;
+}
+
+static SYSCTL_UINT_CONV_CUSTOM(, sysctl_user_to_kern_uint_conv,
+                              sysctl_kern_to_user_uint_conv)
 
+static const char proc_wspace_sep[] = { ' ', '\t', '\n' };
 
 static int do_proc_dointvec(const struct ctl_table *table, int dir,
                  void *buffer, size_t *lenp, loff_t *ppos,
@@ -660,7 +673,7 @@ int do_proc_douintvec(const struct ctl_table *table, int dir, void *buffer,
        }
 
        if (!conv)
-               conv = do_proc_douintvec_conv;
+               conv = do_proc_uint_conv;
 
        if (SYSCTL_USER_TO_KERN(dir))
                return do_proc_douintvec_w(table, buffer, lenp, ppos, conv);
@@ -743,7 +756,7 @@ int proc_douintvec(const struct ctl_table *table, int dir, void *buffer,
                size_t *lenp, loff_t *ppos)
 {
        return do_proc_douintvec(table, dir, buffer, lenp, ppos,
-                                do_proc_douintvec_conv);
+                                do_proc_uint_conv);
 }
 
 /**
@@ -779,7 +792,7 @@ static int do_proc_douintvec_minmax_conv(unsigned long *u_ptr,
        /* When writing to the kernel use a temp local uint for bounds-checking */
        unsigned int *up = SYSCTL_USER_TO_KERN(dir) ? &tmp : k_ptr;
 
-       ret = do_proc_douintvec_conv(u_ptr, up, dir, table);
+       ret = do_proc_uint_conv(u_ptr, up, dir, table);
        if (ret)
                return ret;