2 files changed, 163 insertions, 2 deletions

diff --git a/fs/dlm/debug_fs.c b/fs/dlm/debug_fs.c
index 9e27a1675794..184be9870c63 100644
--- a/fs/dlm/debug_fs.c
+++ b/fs/dlm/debug_fs.c
@@ -27,6 +27,8 @@ static struct dentry *dlm_root;
 
 struct rsb_iter {
         int entry;
+        int master;
+        int header;
         struct dlm_ls *ls;
         struct list_head *next;
         struct dlm_rsb *rsb;
@@ -86,6 +88,8 @@ static int print_resource(struct dlm_rsb *res, struct seq_file *s)
         struct dlm_lkb *lkb;
         int i, lvblen = res->res_ls->ls_lvblen, recover_list, root_list;
 
+        lock_rsb(res);
+
         seq_printf(s, "\nResource %p Name (len=%d) \"", res, res->res_length);
         for (i = 0; i < res->res_length; i++) {
                 if (isprint(res->res_name[i]))
@@ -152,6 +156,59 @@ static int print_resource(struct dlm_rsb *res, struct seq_file *s)
                 seq_printf(s, "\n");
         }
  out:
+        unlock_rsb(res);
+        return 0;
+}
+
+static void print_master_lock(struct seq_file *s, struct dlm_lkb *lkb,
+                              struct dlm_rsb *r)
+{
+        struct dlm_user_args *ua;
+        unsigned int waiting = 0;
+        uint64_t xid = 0;
+
+        if (lkb->lkb_flags & DLM_IFL_USER) {
+                ua = (struct dlm_user_args *) lkb->lkb_astparam;
+                if (ua)
+                        xid = ua->xid;
+        }
+
+        if (lkb->lkb_timestamp)
+                waiting = jiffies_to_msecs(jiffies - lkb->lkb_timestamp);
+
+        /* id nodeid remid pid xid flags sts grmode rqmode time_ms len name */
+
+        seq_printf(s, "%x %d %x %u %llu %x %d %d %d %u %d \"%s\"\n",
+                   lkb->lkb_id,
+                   lkb->lkb_nodeid,
+                   lkb->lkb_remid,
+                   lkb->lkb_ownpid,
+                   (unsigned long long)xid,
+                   lkb->lkb_exflags,
+                   lkb->lkb_status,
+                   lkb->lkb_grmode,
+                   lkb->lkb_rqmode,
+                   waiting,
+                   r->res_length,
+                   r->res_name);
+}
+
+static int print_master_resource(struct dlm_rsb *r, struct seq_file *s)
+{
+        struct dlm_lkb *lkb;
+
+        lock_rsb(r);
+
+        list_for_each_entry(lkb, &r->res_grantqueue, lkb_statequeue)
+                print_master_lock(s, lkb, r);
+
+        list_for_each_entry(lkb, &r->res_convertqueue, lkb_statequeue)
+                print_master_lock(s, lkb, r);
+
+        list_for_each_entry(lkb, &r->res_waitqueue, lkb_statequeue)
+                print_master_lock(s, lkb, r);
+
+        unlock_rsb(r);
         return 0;
 }
 
@@ -209,7 +266,7 @@ static struct rsb_iter *rsb_iter_init(struct dlm_ls *ls)
 {
         struct rsb_iter *ri;
 
-        ri = kmalloc(sizeof *ri, GFP_KERNEL);
+        ri = kzalloc(sizeof *ri, GFP_KERNEL);
         if (!ri)
                 return NULL;
 
@@ -267,7 +324,17 @@ static int rsb_seq_show(struct seq_file *file, void *iter_ptr)
 {
         struct rsb_iter *ri = iter_ptr;
 
-        print_resource(ri->rsb, file);
+        if (ri->master) {
+                if (ri->header) {
+                        seq_printf(file, "id nodeid remid pid xid flags sts "
+                                         "grmode rqmode time_ms len name\n");
+                        ri->header = 0;
+                }
+                if (is_master(ri->rsb))
+                        print_master_resource(ri->rsb, file);
+        } else {
+                print_resource(ri->rsb, file);
+        }
 
         return 0;
 }
@@ -303,6 +370,83 @@ static const struct file_operations rsb_fops = {
 };
 
 /*
+ * Dump master lock state
+ */
+
+static struct rsb_iter *master_iter_init(struct dlm_ls *ls, loff_t *pos)
+{
+        struct rsb_iter *ri;
+
+        ri = kzalloc(sizeof *ri, GFP_KERNEL);
+        if (!ri)
+                return NULL;
+
+        ri->ls = ls;
+        ri->entry = 0;
+        ri->next = NULL;
+        ri->master = 1;
+
+        if (*pos == 0)
+                ri->header = 1;
+
+        if (rsb_iter_next(ri)) {
+                rsb_iter_free(ri);
+                return NULL;
+        }
+
+        return ri;
+}
+
+static void *master_seq_start(struct seq_file *file, loff_t *pos)
+{
+        struct rsb_iter *ri;
+        loff_t n = *pos;
+
+        ri = master_iter_init(file->private, pos);
+        if (!ri)
+                return NULL;
+
+        while (n--) {
+                if (rsb_iter_next(ri)) {
+                        rsb_iter_free(ri);
+                        return NULL;
+                }
+        }
+
+        return ri;
+}
+
+static struct seq_operations master_seq_ops = {
+        .start = master_seq_start,
+        .next  = rsb_seq_next,
+        .stop  = rsb_seq_stop,
+        .show  = rsb_seq_show,
+};
+
+static int master_open(struct inode *inode, struct file *file)
+{
+        struct seq_file *seq;
+        int ret;
+
+        ret = seq_open(file, &master_seq_ops);
+        if (ret)
+                return ret;
+
+        seq = file->private_data;
+        seq->private = inode->i_private;
+
+        return 0;
+}
+
+static const struct file_operations master_fops = {
+        .owner   = THIS_MODULE,
+        .open    = master_open,
+        .read    = seq_read,
+        .llseek  = seq_lseek,
+        .release = seq_release
+};
+
+/*
  * dump lkb's on the ls_waiters list
  */
 
@@ -369,6 +513,20 @@ int dlm_create_debug_file(struct dlm_ls *ls)
                 return -ENOMEM;
         }
 
+        memset(name, 0, sizeof(name));
+        snprintf(name, DLM_LOCKSPACE_LEN+8, "%s_master", ls->ls_name);
+
+        ls->ls_debug_master_dentry = debugfs_create_file(name,
+                                                         S_IFREG | S_IRUGO,
+                                                         dlm_root,
+                                                         ls,
+                                                         &master_fops);
+        if (!ls->ls_debug_master_dentry) {
+                debugfs_remove(ls->ls_debug_waiters_dentry);
+                debugfs_remove(ls->ls_debug_rsb_dentry);
+                return -ENOMEM;
+        }
+
         return 0;
 }
 
@@ -378,6 +536,8 @@ void dlm_delete_debug_file(struct dlm_ls *ls)
                 debugfs_remove(ls->ls_debug_rsb_dentry);
         if (ls->ls_debug_waiters_dentry)
                 debugfs_remove(ls->ls_debug_waiters_dentry);
+        if (ls->ls_debug_master_dentry)
+                debugfs_remove(ls->ls_debug_master_dentry);
 }
 
 int dlm_register_debugfs(void)
diff --git a/fs/dlm/dlm_internal.h b/fs/dlm/dlm_internal.h
index a006fa59e7da..f2c85493c0c6 100644
--- a/fs/dlm/dlm_internal.h
+++ b/fs/dlm/dlm_internal.h
@@ -470,6 +470,7 @@ struct dlm_ls {
 
         struct dentry           *ls_debug_rsb_dentry; /* debugfs */
         struct dentry           *ls_debug_waiters_dentry; /* debugfs */
+        struct dentry           *ls_debug_master_dentry; /* debugfs */
 
         wait_queue_head_t       ls_uevent_wait; /* user part of join/leave */
         int                     ls_uevent_result;