ocfs2: local mounts

This allows users to format an ocfs2 file system with a special flag,
OCFS2_FEATURE_INCOMPAT_LOCAL_MOUNT. When the file system sees this flag, it
will not use any cluster services, nor will it require a cluster
configuration, thus acting like a 'local' file system.

Signed-off-by: Sunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>

1 files changed, 59 insertions, 20 deletions

diff --git a/fs/ocfs2/dlmglue.c b/fs/ocfs2/dlmglue.c
index 69fba16efbd1..e6220137bf69 100644
--- a/fs/ocfs2/dlmglue.c
+++ b/fs/ocfs2/dlmglue.c
@@ -770,7 +770,7 @@ static int ocfs2_lock_create(struct ocfs2_super *osb,
                              int dlm_flags)
 {
         int ret = 0;
-        enum dlm_status status;
+        enum dlm_status status = DLM_NORMAL;
         unsigned long flags;
 
         mlog_entry_void();
@@ -1138,6 +1138,7 @@ int ocfs2_rw_lock(struct inode *inode, int write)
 {
         int status, level;
         struct ocfs2_lock_res *lockres;
+        struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
 
         BUG_ON(!inode);
 
@@ -1147,6 +1148,9 @@ int ocfs2_rw_lock(struct inode *inode, int write)
              (unsigned long long)OCFS2_I(inode)->ip_blkno,
              write ? "EXMODE" : "PRMODE");
 
+        if (ocfs2_mount_local(osb))
+                return 0;
+
         lockres = &OCFS2_I(inode)->ip_rw_lockres;
 
         level = write ? LKM_EXMODE : LKM_PRMODE;
@@ -1164,6 +1168,7 @@ void ocfs2_rw_unlock(struct inode *inode, int write)
 {
         int level = write ? LKM_EXMODE : LKM_PRMODE;
         struct ocfs2_lock_res *lockres = &OCFS2_I(inode)->ip_rw_lockres;
+        struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
 
         mlog_entry_void();
 
@@ -1171,7 +1176,8 @@ void ocfs2_rw_unlock(struct inode *inode, int write)
              (unsigned long long)OCFS2_I(inode)->ip_blkno,
              write ? "EXMODE" : "PRMODE");
 
-        ocfs2_cluster_unlock(OCFS2_SB(inode->i_sb), lockres, level);
+        if (!ocfs2_mount_local(osb))
+                ocfs2_cluster_unlock(OCFS2_SB(inode->i_sb), lockres, level);
 
         mlog_exit_void();
 }
@@ -1182,6 +1188,7 @@ int ocfs2_data_lock_full(struct inode *inode,
 {
         int status = 0, level;
         struct ocfs2_lock_res *lockres;
+        struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
 
         BUG_ON(!inode);
 
@@ -1201,6 +1208,9 @@ int ocfs2_data_lock_full(struct inode *inode,
                 goto out;
         }
 
+        if (ocfs2_mount_local(osb))
+                goto out;
+
         lockres = &OCFS2_I(inode)->ip_data_lockres;
 
         level = write ? LKM_EXMODE : LKM_PRMODE;
@@ -1269,6 +1279,7 @@ void ocfs2_data_unlock(struct inode *inode,
 {
         int level = write ? LKM_EXMODE : LKM_PRMODE;
         struct ocfs2_lock_res *lockres = &OCFS2_I(inode)->ip_data_lockres;
+        struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
 
         mlog_entry_void();
 
@@ -1276,7 +1287,8 @@ void ocfs2_data_unlock(struct inode *inode,
              (unsigned long long)OCFS2_I(inode)->ip_blkno,
              write ? "EXMODE" : "PRMODE");
 
-        if (!ocfs2_is_hard_readonly(OCFS2_SB(inode->i_sb)))
+        if (!ocfs2_is_hard_readonly(OCFS2_SB(inode->i_sb)) &&
+            !ocfs2_mount_local(osb))
                 ocfs2_cluster_unlock(OCFS2_SB(inode->i_sb), lockres, level);
 
         mlog_exit_void();
@@ -1467,8 +1479,9 @@ static int ocfs2_meta_lock_update(struct inode *inode,
 {
         int status = 0;
         struct ocfs2_inode_info *oi = OCFS2_I(inode);
-        struct ocfs2_lock_res *lockres;
+        struct ocfs2_lock_res *lockres = NULL;
         struct ocfs2_dinode *fe;
+        struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
 
         mlog_entry_void();
 
@@ -1483,10 +1496,12 @@ static int ocfs2_meta_lock_update(struct inode *inode,
         }
         spin_unlock(&oi->ip_lock);
 
-        lockres = &oi->ip_meta_lockres;
+        if (!ocfs2_mount_local(osb)) {
+                lockres = &oi->ip_meta_lockres;
 
-        if (!ocfs2_should_refresh_lock_res(lockres))
-                goto bail;
+                if (!ocfs2_should_refresh_lock_res(lockres))
+                        goto bail;
+        }
 
         /* This will discard any caching information we might have had
          * for the inode metadata. */
@@ -1496,7 +1511,7 @@ static int ocfs2_meta_lock_update(struct inode *inode,
          * map (directories, bitmap files, etc) */
         ocfs2_extent_map_trunc(inode, 0);
 
-        if (ocfs2_meta_lvb_is_trustable(inode, lockres)) {
+        if (lockres && ocfs2_meta_lvb_is_trustable(inode, lockres)) {
                 mlog(0, "Trusting LVB on inode %llu\n",
                      (unsigned long long)oi->ip_blkno);
                 ocfs2_refresh_inode_from_lvb(inode);
@@ -1543,7 +1558,8 @@ static int ocfs2_meta_lock_update(struct inode *inode,
 
         status = 0;
 bail_refresh:
-        ocfs2_complete_lock_res_refresh(lockres, status);
+        if (lockres)
+                ocfs2_complete_lock_res_refresh(lockres, status);
 bail:
         mlog_exit(status);
         return status;
@@ -1585,7 +1601,7 @@ int ocfs2_meta_lock_full(struct inode *inode,
                          int arg_flags)
 {
         int status, level, dlm_flags, acquired;
-        struct ocfs2_lock_res *lockres;
+        struct ocfs2_lock_res *lockres = NULL;
         struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
         struct buffer_head *local_bh = NULL;
 
@@ -1607,6 +1623,9 @@ int ocfs2_meta_lock_full(struct inode *inode,
                 goto bail;
         }
 
+        if (ocfs2_mount_local(osb))
+                goto local;
+
         if (!(arg_flags & OCFS2_META_LOCK_RECOVERY))
                 wait_event(osb->recovery_event,
                            ocfs2_node_map_is_empty(osb, &osb->recovery_map));
@@ -1636,6 +1655,7 @@ int ocfs2_meta_lock_full(struct inode *inode,
                 wait_event(osb->recovery_event,
                            ocfs2_node_map_is_empty(osb, &osb->recovery_map));
 
+local:
         /*
          * We only see this flag if we're being called from
          * ocfs2_read_locked_inode(). It means we're locking an inode
@@ -1644,7 +1664,8 @@ int ocfs2_meta_lock_full(struct inode *inode,
          */
         if (inode->i_state & I_NEW) {
                 status = 0;
-                ocfs2_complete_lock_res_refresh(lockres, 0);
+                if (lockres)
+                        ocfs2_complete_lock_res_refresh(lockres, 0);
                 goto bail;
         }
 
@@ -1767,6 +1788,7 @@ void ocfs2_meta_unlock(struct inode *inode,
 {
         int level = ex ? LKM_EXMODE : LKM_PRMODE;
         struct ocfs2_lock_res *lockres = &OCFS2_I(inode)->ip_meta_lockres;
+        struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
 
         mlog_entry_void();
 
@@ -1774,7 +1796,8 @@ void ocfs2_meta_unlock(struct inode *inode,
              (unsigned long long)OCFS2_I(inode)->ip_blkno,
              ex ? "EXMODE" : "PRMODE");
 
-        if (!ocfs2_is_hard_readonly(OCFS2_SB(inode->i_sb)))
+        if (!ocfs2_is_hard_readonly(OCFS2_SB(inode->i_sb)) &&
+            !ocfs2_mount_local(osb))
                 ocfs2_cluster_unlock(OCFS2_SB(inode->i_sb), lockres, level);
 
         mlog_exit_void();
@@ -1783,7 +1806,7 @@ void ocfs2_meta_unlock(struct inode *inode,
 int ocfs2_super_lock(struct ocfs2_super *osb,
                      int ex)
 {
-        int status;
+        int status = 0;
         int level = ex ? LKM_EXMODE : LKM_PRMODE;
         struct ocfs2_lock_res *lockres = &osb->osb_super_lockres;
         struct buffer_head *bh;
@@ -1794,6 +1817,9 @@ int ocfs2_super_lock(struct ocfs2_super *osb,
         if (ocfs2_is_hard_readonly(osb))
                 return -EROFS;
 
+        if (ocfs2_mount_local(osb))
+                goto bail;
+
         status = ocfs2_cluster_lock(osb, lockres, level, 0, 0);
         if (status < 0) {
                 mlog_errno(status);
@@ -1832,7 +1858,8 @@ void ocfs2_super_unlock(struct ocfs2_super *osb,
         int level = ex ? LKM_EXMODE : LKM_PRMODE;
         struct ocfs2_lock_res *lockres = &osb->osb_super_lockres;
 
-        ocfs2_cluster_unlock(osb, lockres, level);
+        if (!ocfs2_mount_local(osb))
+                ocfs2_cluster_unlock(osb, lockres, level);
 }
 
 int ocfs2_rename_lock(struct ocfs2_super *osb)
@@ -1843,6 +1870,9 @@ int ocfs2_rename_lock(struct ocfs2_super *osb)
         if (ocfs2_is_hard_readonly(osb))
                 return -EROFS;
 
+        if (ocfs2_mount_local(osb))
+                return 0;
+
         status = ocfs2_cluster_lock(osb, lockres, LKM_EXMODE, 0, 0);
         if (status < 0)
                 mlog_errno(status);
@@ -1854,7 +1884,8 @@ void ocfs2_rename_unlock(struct ocfs2_super *osb)
 {
         struct ocfs2_lock_res *lockres = &osb->osb_rename_lockres;
 
-        ocfs2_cluster_unlock(osb, lockres, LKM_EXMODE);
+        if (!ocfs2_mount_local(osb))
+                ocfs2_cluster_unlock(osb, lockres, LKM_EXMODE);
 }
 
 int ocfs2_dentry_lock(struct dentry *dentry, int ex)
@@ -1869,6 +1900,9 @@ int ocfs2_dentry_lock(struct dentry *dentry, int ex)
         if (ocfs2_is_hard_readonly(osb))
                 return -EROFS;
 
+        if (ocfs2_mount_local(osb))
+                return 0;
+
         ret = ocfs2_cluster_lock(osb, &dl->dl_lockres, level, 0, 0);
         if (ret < 0)
                 mlog_errno(ret);
@@ -1882,7 +1916,8 @@ void ocfs2_dentry_unlock(struct dentry *dentry, int ex)
         struct ocfs2_dentry_lock *dl = dentry->d_fsdata;
         struct ocfs2_super *osb = OCFS2_SB(dentry->d_sb);
 
-        ocfs2_cluster_unlock(osb, &dl->dl_lockres, level);
+        if (!ocfs2_mount_local(osb))
+                ocfs2_cluster_unlock(osb, &dl->dl_lockres, level);
 }
 
 /* Reference counting of the dlm debug structure. We want this because
@@ -2145,12 +2180,15 @@ static void ocfs2_dlm_shutdown_debug(struct ocfs2_super *osb)
 
 int ocfs2_dlm_init(struct ocfs2_super *osb)
 {
-        int status;
+        int status = 0;
         u32 dlm_key;
-        struct dlm_ctxt *dlm;
+        struct dlm_ctxt *dlm = NULL;
 
         mlog_entry_void();
 
+        if (ocfs2_mount_local(osb))
+                goto local;
+
         status = ocfs2_dlm_init_debug(osb);
         if (status < 0) {
                 mlog_errno(status);
@@ -2178,11 +2216,12 @@ int ocfs2_dlm_init(struct ocfs2_super *osb)
                 goto bail;
         }
 
+        dlm_register_eviction_cb(dlm, &osb->osb_eviction_cb);
+
+local:
         ocfs2_super_lock_res_init(&osb->osb_super_lockres, osb);
         ocfs2_rename_lock_res_init(&osb->osb_rename_lockres, osb);
 
-        dlm_register_eviction_cb(dlm, &osb->osb_eviction_cb);
-
         osb->dlm = dlm;
 
         status = 0;