ocfs2: Abstract out node number queries.

ocfs2 asks the cluster stack for the local node's node number for two
reasons; to fill the slot map and to print it. While the slot map isn't
necessary for userspace cluster stacks, the printing is very nice for
debugging. Thus we add ocfs2_cluster_this_node() as a generic API to get
this value. It is anticipated that the slot map will not be used under a
userspace cluster stack, so validity checks of the node num only need to
exist in the slot map code. Otherwise, it just gets used and printed as an
opaque value.

[ Fixed up some "int" versus "unsigned int" issues and made osb->node_num
  truly opaque. --Mark ]

Signed-off-by: Joel Becker <joel.becker@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>

5 files changed, 30 insertions, 14 deletions

diff --git a/fs/ocfs2/ocfs2.h b/fs/ocfs2/ocfs2.h
index 664e4fe3eab5..7006abaffd47 100644
--- a/fs/ocfs2/ocfs2.h
+++ b/fs/ocfs2/ocfs2.h
@@ -218,7 +218,7 @@ struct ocfs2_super
         unsigned int s_atime_quantum;
 
         unsigned int max_slots;
-        s16 node_num;
+        unsigned int node_num;
         int slot_num;
         int preferred_slot;
         int s_sectsize_bits;
diff --git a/fs/ocfs2/slot_map.c b/fs/ocfs2/slot_map.c
index 63fb1b26d964..bb5ff8939bf1 100644
--- a/fs/ocfs2/slot_map.c
+++ b/fs/ocfs2/slot_map.c
@@ -73,8 +73,6 @@ static void ocfs2_set_slot(struct ocfs2_slot_info *si,
                            int slot_num, unsigned int node_num)
 {
         BUG_ON((slot_num < 0) || (slot_num >= si->si_num_slots));
-        BUG_ON((node_num == O2NM_INVALID_NODE_NUM) ||
-               (node_num >= O2NM_MAX_NODES));
 
         si->si_slots[slot_num].sl_valid = 1;
         si->si_slots[slot_num].sl_node_num = node_num;
diff --git a/fs/ocfs2/stackglue.c b/fs/ocfs2/stackglue.c
index f6f309a08344..814686356cc6 100644
--- a/fs/ocfs2/stackglue.c
+++ b/fs/ocfs2/stackglue.c
@@ -25,6 +25,8 @@
 #include <linux/fs.h>
 
 #include "cluster/masklog.h"
+#include "cluster/nodemanager.h"
+
 #include "stackglue.h"
 
 static struct ocfs2_locking_protocol *lproto;
@@ -371,6 +373,21 @@ int ocfs2_cluster_disconnect(struct ocfs2_cluster_connection *conn)
         return 0;
 }
 
+int ocfs2_cluster_this_node(unsigned int *node)
+{
+        int node_num;
+
+        node_num = o2nm_this_node();
+        if (node_num == O2NM_INVALID_NODE_NUM)
+                return -ENOENT;
+
+        if (node_num >= O2NM_MAX_NODES)
+                return -EOVERFLOW;
+
+        *node = node_num;
+        return 0;
+}
+
 void o2cb_get_stack(struct ocfs2_locking_protocol *proto)
 {
         BUG_ON(proto == NULL);
diff --git a/fs/ocfs2/stackglue.h b/fs/ocfs2/stackglue.h
index 3900b5c3933c..ccb03991b514 100644
--- a/fs/ocfs2/stackglue.h
+++ b/fs/ocfs2/stackglue.h
@@ -74,6 +74,7 @@ int ocfs2_cluster_connect(const char *group,
                           void *recovery_data,
                           struct ocfs2_cluster_connection **conn);
 int ocfs2_cluster_disconnect(struct ocfs2_cluster_connection *conn);
+int ocfs2_cluster_this_node(unsigned int *node);
 
 int ocfs2_dlm_lock(struct ocfs2_cluster_connection *conn,
                    int mode,
diff --git a/fs/ocfs2/super.c b/fs/ocfs2/super.c
index 0ee49757467d..d3c4d323fab5 100644
--- a/fs/ocfs2/super.c
+++ b/fs/ocfs2/super.c
@@ -694,7 +694,7 @@ static int ocfs2_fill_super(struct super_block *sb, void *data, int silent)
         if (ocfs2_mount_local(osb))
                 snprintf(nodestr, sizeof(nodestr), "local");
         else
-                snprintf(nodestr, sizeof(nodestr), "%d", osb->node_num);
+                snprintf(nodestr, sizeof(nodestr), "%u", osb->node_num);
 
         printk(KERN_INFO "ocfs2: Mounting device (%s) on (node %s, slot %d) "
                "with %s data mode.\n",
@@ -1145,16 +1145,17 @@ static int ocfs2_fill_local_node_info(struct ocfs2_super *osb)
          * desirable. */
         if (ocfs2_mount_local(osb))
                 osb->node_num = 0;
-        else
-                osb->node_num = o2nm_this_node();
-
-        if (osb->node_num == O2NM_MAX_NODES) {
-                mlog(ML_ERROR, "could not find this host's node number\n");
-                status = -ENOENT;
-                goto bail;
+        else {
+                status = ocfs2_cluster_this_node(&osb->node_num);
+                if (status < 0) {
+                        mlog_errno(status);
+                        mlog(ML_ERROR,
+                             "could not find this host's node number\n");
+                        goto bail;
+                }
         }
 
-        mlog(0, "I am node %d\n", osb->node_num);
+        mlog(0, "I am node %u\n", osb->node_num);
 
         status = 0;
 bail:
@@ -1282,7 +1283,7 @@ static void ocfs2_dismount_volume(struct super_block *sb, int mnt_err)
         if (ocfs2_mount_local(osb))
                 snprintf(nodestr, sizeof(nodestr), "local");
         else
-                snprintf(nodestr, sizeof(nodestr), "%d", osb->node_num);
+                snprintf(nodestr, sizeof(nodestr), "%u", osb->node_num);
 
         printk(KERN_INFO "ocfs2: Unmounting device (%s) on (node %s)\n",
                osb->dev_str, nodestr);
@@ -1384,7 +1385,6 @@ static int ocfs2_initialize_super(struct super_block *sb,
 
         osb->s_atime_quantum = OCFS2_DEFAULT_ATIME_QUANTUM;
 
-        osb->node_num = O2NM_INVALID_NODE_NUM;
         osb->slot_num = OCFS2_INVALID_SLOT;
 
         osb->local_alloc_state = OCFS2_LA_UNUSED;