lib/vsprintf.c: Add %pMF to format FDDI bit reversed MAC addresses
On Mon, 2010-01-04 at 23:43 +0000, Maciej W. Rozycki wrote:
> The example below shows an address, and the sequence of bits or symbols
> that would be transmitted when the address is used in the Source Address
> or Destination Address fields on the MAC header. The transmission line
> shows the address bits in the order transmitted, from left to right. For
> IEEE 802 LANs these correspond to actual bits on the medium. The FDDI
> symbols line shows how the FDDI PHY sends the address bits as encoded
> symbols.
>
> MSB: 35:7B:12:00:00:01
> Canonical: AC-DE-48-00-00-80
> Transmission: 00110101 01111011 00010010 00000000 00000000 00000001
> FDDI Symbols: 35 7B 12 00 00 01"
>
> Please note that this address has its group bit clear.
>
> This notation is also defined in the "FDDI MEDIA ACCESS CONTROL-2
> (MAC-2)" (X3T9/92-120) document although that book does not have a need
> to use the MSB form and it's skipped.
Adds 6 bytes to object size for x86
New:
$ size lib/vsprintf.o
text data bss dec hex filename
8664 0 2 8666 21da lib/vsprintf.o
$ size lib/vsprintf.o
text data bss dec hex filename
8658 0 2 8660 21d4 lib/vsprintf.o
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/lib/vsprintf.c b/lib/vsprintf.c
index d4996cf..dc48d2b 100644
--- a/lib/vsprintf.c
+++ b/lib/vsprintf.c
@@ -25,6 +25,7 @@
#include <linux/kallsyms.h>
#include <linux/uaccess.h>
#include <linux/ioport.h>
+#include <linux/bitrev.h>
#include <net/addrconf.h>
#include <asm/page.h> /* for PAGE_SIZE */
@@ -681,11 +682,21 @@
char mac_addr[sizeof("xx:xx:xx:xx:xx:xx")];
char *p = mac_addr;
int i;
+ bool bitrev;
+ char separator;
+
+ if (fmt[1] == 'F') { /* FDDI canonical format */
+ bitrev = true;
+ separator = '-';
+ } else {
+ bitrev = false;
+ separator = ':';
+ }
for (i = 0; i < 6; i++) {
- p = pack_hex_byte(p, addr[i]);
+ p = pack_hex_byte(p, bitrev ? bitrev8(addr[i]) : addr[i]);
if (fmt[0] == 'M' && i != 5)
- *p++ = ':';
+ *p++ = separator;
}
*p = '\0';
@@ -896,6 +907,10 @@
* - 'M' For a 6-byte MAC address, it prints the address in the
* usual colon-separated hex notation
* - 'm' For a 6-byte MAC address, it prints the hex address without colons
+ * - 'MF' For a 6-byte MAC FDDI address, it prints the address
+ * with a dash-separated hex notation with bit reversed bytes
+ * - 'mF' For a 6-byte MAC FDDI address, it prints the address
+ * in hex notation without separators with bit reversed bytes
* - 'I' [46] for IPv4/IPv6 addresses printed in the usual way
* IPv4 uses dot-separated decimal without leading 0's (1.2.3.4)
* IPv6 uses colon separated network-order 16 bit hex with leading 0's
@@ -939,6 +954,7 @@
return resource_string(buf, end, ptr, spec, fmt);
case 'M': /* Colon separated: 00:01:02:03:04:05 */
case 'm': /* Contiguous: 000102030405 */
+ /* [mM]F (FDDI, bit reversed) */
return mac_address_string(buf, end, ptr, spec, fmt);
case 'I': /* Formatted IP supported
* 4: 1.2.3.4
