[SCSI] Improve message printing code

Fix a bug where we would consume one byte too many in the message
printing code.
Add support for 256-byte long messages.
Add support for the Modify Bidirectional Data Pointer message.

Signed-off-by: Matthew Wilcox <matthew@wil.cx>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>

1 files changed, 19 insertions, 5 deletions

diff --git a/drivers/scsi/scsi_transport_spi.c b/drivers/scsi/scsi_transport_spi.c
index c63adff15afa..0b29ee9989a4 100644
--- a/drivers/scsi/scsi_transport_spi.c
+++ b/drivers/scsi/scsi_transport_spi.c
@@ -1105,7 +1105,7 @@ static const char * const two_byte_msgs[] = {
 static const char * const extended_msgs[] = {
 /* 0x00 */ "Modify Data Pointer", "Synchronous Data Transfer Request",
 /* 0x02 */ "SCSI-I Extended Identify", "Wide Data Transfer Request",
-/* 0x04 */ "Parallel Protocol Request"
+/* 0x04 */ "Parallel Protocol Request", "Modify Bidirectional Data Pointer"
 };
 
 static void print_nego(const unsigned char *msg, int per, int off, int width)
@@ -1122,11 +1122,20 @@ static void print_nego(const unsigned char *msg, int per, int off, int width)
                 printk("width = %d ", 8 << msg[width]);
 }
 
+static void print_ptr(const unsigned char *msg, int msb, const char *desc)
+{
+        int ptr = (msg[msb] << 24) | (msg[msb+1] << 16) | (msg[msb+2] << 8) |
+                        msg[msb+3];
+        printk("%s = %d ", desc, ptr);
+}
+
 int spi_print_msg(const unsigned char *msg)
 {
         int len = 0, i;
         if (msg[0] == EXTENDED_MESSAGE) {
-                len = 3 + msg[1];
+                len = 2 + msg[1];
+                if (len == 2)
+                        len += 256;
                 if (msg[2] < ARRAY_SIZE(extended_msgs))
                         printk ("%s ", extended_msgs[msg[2]]); 
                 else 
@@ -1134,8 +1143,7 @@ int spi_print_msg(const unsigned char *msg)
                                 (int) msg[2]);
                 switch (msg[2]) {
                 case EXTENDED_MODIFY_DATA_POINTER:
-                        printk("pointer = %d ", (msg[3] << 24) |
-                                (msg[4] << 16) | (msg[5] << 8) | msg[6]);
+                        print_ptr(msg, 3, "pointer");
                         break;
                 case EXTENDED_SDTR:
                         print_nego(msg, 3, 4, 0);
@@ -1146,6 +1154,10 @@ int spi_print_msg(const unsigned char *msg)
                 case EXTENDED_PPR:
                         print_nego(msg, 3, 5, 6);
                         break;
+                case EXTENDED_MODIFY_BIDI_DATA_PTR:
+                        print_ptr(msg, 3, "out");
+                        print_ptr(msg, 7, "in");
+                        break;
                 default:
                 for (i = 2; i < len; ++i) 
                         printk("%02x ", msg[i]);
@@ -1186,7 +1198,9 @@ int spi_print_msg(const unsigned char *msg)
         int len = 0, i;
 
         if (msg[0] == EXTENDED_MESSAGE) {
-                len = 3 + msg[1];
+                len = 2 + msg[1];
+                if (len == 2)
+                        len += 256;
                 for (i = 0; i < len; ++i)
                         printk("%02x ", msg[i]);
         /* Identify */