lib/vsprintf: Prepare for more general use of ptr_to_id()

Move the function and its dependencies up so it can be called from
special pointer type formatting routines.

Link: http://lkml.kernel.org/r/20181011084249.4520-2-geert+renesas@glider.be
To: "Tobin C . Harding" <me@tobin.cc>
To: Andrew Morton <akpm@linux-foundation.org>
To: Jonathan Corbet <corbet@lwn.net>
Cc: linux-doc@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
[pmladek@suse.com: Split into separate patch]
Signed-off-by: Petr Mladek <pmladek@suse.com>

diff --git a/lib/vsprintf.c b/lib/vsprintf.c
index c40fdabbd592c0a1ac37ecdf73444b4dad278dfe..94940ba3a3bcdaa3f52b31119491ad4ab706d231 100644 (file)
--- a/lib/vsprintf.c
+++ b/lib/vsprintf.c
@@ -612,6 +612,109 @@ char *string(char *buf, char *end, const char *s, struct printf_spec spec)
        return widen_string(buf, len, end, spec);
 }
 
+static noinline_for_stack
+char *pointer_string(char *buf, char *end, const void *ptr,
+                    struct printf_spec spec)
+{
+       spec.base = 16;
+       spec.flags |= SMALL;
+       if (spec.field_width == -1) {
+               spec.field_width = 2 * sizeof(ptr);
+               spec.flags |= ZEROPAD;
+       }
+
+       return number(buf, end, (unsigned long int)ptr, spec);
+}
+
+/* Make pointers available for printing early in the boot sequence. */
+static int debug_boot_weak_hash __ro_after_init;
+
+static int __init debug_boot_weak_hash_enable(char *str)
+{
+       debug_boot_weak_hash = 1;
+       pr_info("debug_boot_weak_hash enabled\n");
+       return 0;
+}
+early_param("debug_boot_weak_hash", debug_boot_weak_hash_enable);
+
+static DEFINE_STATIC_KEY_TRUE(not_filled_random_ptr_key);
+static siphash_key_t ptr_key __read_mostly;
+
+static void enable_ptr_key_workfn(struct work_struct *work)
+{
+       get_random_bytes(&ptr_key, sizeof(ptr_key));
+       /* Needs to run from preemptible context */
+       static_branch_disable(&not_filled_random_ptr_key);
+}
+
+static DECLARE_WORK(enable_ptr_key_work, enable_ptr_key_workfn);
+
+static void fill_random_ptr_key(struct random_ready_callback *unused)
+{
+       /* This may be in an interrupt handler. */
+       queue_work(system_unbound_wq, &enable_ptr_key_work);
+}
+
+static struct random_ready_callback random_ready = {
+       .func = fill_random_ptr_key
+};
+
+static int __init initialize_ptr_random(void)
+{
+       int key_size = sizeof(ptr_key);
+       int ret;
+
+       /* Use hw RNG if available. */
+       if (get_random_bytes_arch(&ptr_key, key_size) == key_size) {
+               static_branch_disable(&not_filled_random_ptr_key);
+               return 0;
+       }
+
+       ret = add_random_ready_callback(&random_ready);
+       if (!ret) {
+               return 0;
+       } else if (ret == -EALREADY) {
+               /* This is in preemptible context */
+               enable_ptr_key_workfn(&enable_ptr_key_work);
+               return 0;
+       }
+
+       return ret;
+}
+early_initcall(initialize_ptr_random);
+
+/* Maps a pointer to a 32 bit unique identifier. */
+static char *ptr_to_id(char *buf, char *end, const void *ptr,
+                      struct printf_spec spec)
+{
+       const char *str = sizeof(ptr) == 8 ? "(____ptrval____)" : "(ptrval)";
+       unsigned long hashval;
+
+       /* When debugging early boot use non-cryptographically secure hash. */
+       if (unlikely(debug_boot_weak_hash)) {
+               hashval = hash_long((unsigned long)ptr, 32);
+               return pointer_string(buf, end, (const void *)hashval, spec);
+       }
+
+       if (static_branch_unlikely(&not_filled_random_ptr_key)) {
+               spec.field_width = 2 * sizeof(ptr);
+               /* string length must be less than default_width */
+               return string(buf, end, str, spec);
+       }
+
+#ifdef CONFIG_64BIT
+       hashval = (unsigned long)siphash_1u64((u64)ptr, &ptr_key);
+       /*
+        * Mask off the first 32 bits, this makes explicit that we have
+        * modified the address (and 32 bits is plenty for a unique ID).
+        */
+       hashval = hashval & 0xffffffff;
+#else
+       hashval = (unsigned long)siphash_1u32((u32)ptr, &ptr_key);
+#endif
+       return pointer_string(buf, end, (const void *)hashval, spec);
+}
+
 static noinline_for_stack
 char *dentry_name(char *buf, char *end, const struct dentry *d, struct printf_spec spec,
                  const char *fmt)
@@ -1357,20 +1460,6 @@ char *uuid_string(char *buf, char *end, const u8 *addr,
        return string(buf, end, uuid, spec);
 }
 
-static noinline_for_stack
-char *pointer_string(char *buf, char *end, const void *ptr,
-                    struct printf_spec spec)
-{
-       spec.base = 16;
-       spec.flags |= SMALL;
-       if (spec.field_width == -1) {
-               spec.field_width = 2 * sizeof(ptr);
-               spec.flags |= ZEROPAD;
-       }
-
-       return number(buf, end, (unsigned long int)ptr, spec);
-}
-
 int kptr_restrict __read_mostly;
 
 static noinline_for_stack
@@ -1651,95 +1740,6 @@ char *device_node_string(char *buf, char *end, struct device_node *dn,
        return widen_string(buf, buf - buf_start, end, spec);
 }
 
-/* Make pointers available for printing early in the boot sequence. */
-static int debug_boot_weak_hash __ro_after_init;
-
-static int __init debug_boot_weak_hash_enable(char *str)
-{
-       debug_boot_weak_hash = 1;
-       pr_info("debug_boot_weak_hash enabled\n");
-       return 0;
-}
-early_param("debug_boot_weak_hash", debug_boot_weak_hash_enable);
-
-static DEFINE_STATIC_KEY_TRUE(not_filled_random_ptr_key);
-static siphash_key_t ptr_key __read_mostly;
-
-static void enable_ptr_key_workfn(struct work_struct *work)
-{
-       get_random_bytes(&ptr_key, sizeof(ptr_key));
-       /* Needs to run from preemptible context */
-       static_branch_disable(&not_filled_random_ptr_key);
-}
-
-static DECLARE_WORK(enable_ptr_key_work, enable_ptr_key_workfn);
-
-static void fill_random_ptr_key(struct random_ready_callback *unused)
-{
-       /* This may be in an interrupt handler. */
-       queue_work(system_unbound_wq, &enable_ptr_key_work);
-}
-
-static struct random_ready_callback random_ready = {
-       .func = fill_random_ptr_key
-};
-
-static int __init initialize_ptr_random(void)
-{
-       int key_size = sizeof(ptr_key);
-       int ret;
-
-       /* Use hw RNG if available. */
-       if (get_random_bytes_arch(&ptr_key, key_size) == key_size) {
-               static_branch_disable(&not_filled_random_ptr_key);
-               return 0;
-       }
-
-       ret = add_random_ready_callback(&random_ready);
-       if (!ret) {
-               return 0;
-       } else if (ret == -EALREADY) {
-               /* This is in preemptible context */
-               enable_ptr_key_workfn(&enable_ptr_key_work);
-               return 0;
-       }
-
-       return ret;
-}
-early_initcall(initialize_ptr_random);
-
-/* Maps a pointer to a 32 bit unique identifier. */
-static char *ptr_to_id(char *buf, char *end, const void *ptr,
-                      struct printf_spec spec)
-{
-       const char *str = sizeof(ptr) == 8 ? "(____ptrval____)" : "(ptrval)";
-       unsigned long hashval;
-
-       /* When debugging early boot use non-cryptographically secure hash. */
-       if (unlikely(debug_boot_weak_hash)) {
-               hashval = hash_long((unsigned long)ptr, 32);
-               return pointer_string(buf, end, (const void *)hashval, spec);
-       }
-
-       if (static_branch_unlikely(&not_filled_random_ptr_key)) {
-               spec.field_width = 2 * sizeof(ptr);
-               /* string length must be less than default_width */
-               return string(buf, end, str, spec);
-       }
-
-#ifdef CONFIG_64BIT
-       hashval = (unsigned long)siphash_1u64((u64)ptr, &ptr_key);
-       /*
-        * Mask off the first 32 bits, this makes explicit that we have
-        * modified the address (and 32 bits is plenty for a unique ID).
-        */
-       hashval = hashval & 0xffffffff;
-#else
-       hashval = (unsigned long)siphash_1u32((u32)ptr, &ptr_key);
-#endif
-       return pointer_string(buf, end, (const void *)hashval, spec);
-}
-
 /*
  * Show a '%p' thing.  A kernel extension is that the '%p' is followed
  * by an extra set of alphanumeric characters that are extended format