illumos gate

These have been in illumos-nexenta for a while. One fixes an uninitialized-variable nit, the other sets the return value of an ioctl to 0 when it otherwise hasn't been touched. There's some small cstyle nits fixed as well.

This will likely be integrated alongside the sTec S112x "skd" driver.

--- /export/home/danmcd/ws/git-illumos/usr/src/uts/common/io/blkdev/blkdev.c    Wed Jul 10 15:49:27 2013
+++ ../../common/io/blkdev/blkdev.c    Mon Aug 12 13:32:00 2013
@@ -540,7 +540,7 @@
     int kmflag)
 {
     bd_xfer_impl_t        *xi;
-    int            rv;
+    int            rv = 0;
     int            status;
     unsigned        dir;
     int            (*cb)(caddr_t);
@@ -683,6 +683,7 @@
     int        rv;
     diskaddr_t    nblks;
     diskaddr_t    lba;
+    int        i;

     _NOTE(ARGUNUSED(credp));

@@ -755,7 +756,7 @@
             rv = EBUSY;
             goto done;
         }
-        for (int i = 0; i < OTYP_LYR; i++) {
+        for (i = 0; i < OTYP_LYR; i++) {
             if (bd->d_open_reg[i] & mask) {
                 rv = EBUSY;
                 goto done;
@@ -788,6 +789,7 @@
     minor_t        part;
     uint64_t    mask;
     boolean_t    last = B_TRUE;
+    int        i;

     _NOTE(ARGUNUSED(flag));
     _NOTE(ARGUNUSED(credp));
@@ -814,12 +816,12 @@
     } else {
         bd->d_open_reg[otyp] &= ~mask;
     }
-    for (int i = 0; i < 64; i++) {
+    for (i = 0; i < 64; i++) {
         if (bd->d_open_lyr[part]) {
             last = B_FALSE;
         }
     }
-    for (int i = 0; last && (i < OTYP_LYR); i++) {
+    for (i = 0; last && (i < OTYP_LYR); i++) {
         if (bd->d_open_reg[i]) {
             last = B_FALSE;
         }
@@ -1041,6 +1043,11 @@
     if (rv != ENOTTY)
         return (rv);

+    if (rvalp != NULL) {
+        /* the return value of the ioctl is 0 by default */
+        *rvalp = 0;
+    }
+
     switch (cmd) {
     case DKIOCGMEDIAINFO: {
         struct dk_minfo minfo;