vsprintf: add %pad extension for dma_addr_t use

dma_addr_t's can be either u32 or u64 depending on a CONFIG option.

There are a few hundred dma_addr_t's printed via either cast to unsigned
long long, unsigned long or no cast at all.

Add %pad to be able to emit them without the cast.

Update Documentation/printk-formats.txt too.

Signed-off-by: Joe Perches <joe@perches.com>
Cc: "Shevchenko, Andriy" <andriy.shevchenko@intel.com>
Cc: Rob Landley <rob@landley.net>
Cc: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Cc: Julia Lawall <julia.lawall@lip6.fr>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2 files changed, 36 insertions, 8 deletions

diff --git a/Documentation/printk-formats.txt b/Documentation/printk-formats.txt
index 445ad743ec81..6f4eb322ffaf 100644
--- a/Documentation/printk-formats.txt
+++ b/Documentation/printk-formats.txt
@@ -55,14 +55,21 @@ Struct Resources:
         For printing struct resources. The 'R' and 'r' specifiers result in a
         printed resource with ('R') or without ('r') a decoded flags member.
 
-Physical addresses:
+Physical addresses types phys_addr_t:
 
-        %pa     0x01234567 or 0x0123456789abcdef
+        %pa[p]  0x01234567 or 0x0123456789abcdef
 
         For printing a phys_addr_t type (and its derivatives, such as
         resource_size_t) which can vary based on build options, regardless of
         the width of the CPU data path. Passed by reference.
 
+DMA addresses types dma_addr_t:
+
+        %pad    0x01234567 or 0x0123456789abcdef
+
+        For printing a dma_addr_t type which can vary based on build options,
+        regardless of the width of the CPU data path. Passed by reference.
+
 Raw buffer as a hex string:
         %*ph    00 01 02  ...  3f
         %*phC   00:01:02: ... :3f
diff --git a/lib/vsprintf.c b/lib/vsprintf.c
index 10909c571494..185b6d300ebc 100644
--- a/lib/vsprintf.c
+++ b/lib/vsprintf.c
@@ -1155,6 +1155,30 @@ char *netdev_feature_string(char *buf, char *end, const u8 *addr,
         return number(buf, end, *(const netdev_features_t *)addr, spec);
 }
 
+static noinline_for_stack
+char *address_val(char *buf, char *end, const void *addr,
+                  struct printf_spec spec, const char *fmt)
+{
+        unsigned long long num;
+
+        spec.flags |= SPECIAL | SMALL | ZEROPAD;
+        spec.base = 16;
+
+        switch (fmt[1]) {
+        case 'd':
+                num = *(const dma_addr_t *)addr;
+                spec.field_width = sizeof(dma_addr_t) * 2 + 2;
+                break;
+        case 'p':
+        default:
+                num = *(const phys_addr_t *)addr;
+                spec.field_width = sizeof(phys_addr_t) * 2 + 2;
+                break;
+        }
+
+        return number(buf, end, num, spec);
+}
+
 int kptr_restrict __read_mostly;
 
 /*
@@ -1218,7 +1242,8 @@ int kptr_restrict __read_mostly;
  *              N no separator
  *            The maximum supported length is 64 bytes of the input. Consider
  *            to use print_hex_dump() for the larger input.
- * - 'a' For a phys_addr_t type and its derivative types (passed by reference)
+ * - 'a[pd]' For address types [p] phys_addr_t, [d] dma_addr_t and derivatives
+ *           (default assumed to be phys_addr_t, passed by reference)
  * - 'd[234]' For a dentry name (optionally 2-4 last components)
  * - 'D[234]' Same as 'd' but for a struct file
  *
@@ -1353,11 +1378,7 @@ char *pointer(const char *fmt, char *buf, char *end, void *ptr,
                 }
                 break;
         case 'a':
-                spec.flags |= SPECIAL | SMALL | ZEROPAD;
-                spec.field_width = sizeof(phys_addr_t) * 2 + 2;
-                spec.base = 16;
-                return number(buf, end,
-                              (unsigned long long) *((phys_addr_t *)ptr), spec);
+                return address_val(buf, end, ptr, spec, fmt);
         case 'd':
                 return dentry_name(buf, end, ptr, spec, fmt);
         case 'D':