5 files changed, 436 insertions, 104 deletions

diff --git a/fs/ocfs2/dcache.c b/fs/ocfs2/dcache.c
index 1a01380e3878..aea457718946 100644
--- a/fs/ocfs2/dcache.c
+++ b/fs/ocfs2/dcache.c
@@ -87,6 +87,8 @@ bail:
         return ret;
 }
 
+DEFINE_SPINLOCK(dentry_attach_lock);
+
 struct dentry_operations ocfs2_dentry_ops = {
         .d_revalidate           = ocfs2_dentry_revalidate,
 };
diff --git a/fs/ocfs2/dcache.h b/fs/ocfs2/dcache.h
index 90072771114b..f1423c2134ee 100644
--- a/fs/ocfs2/dcache.h
+++ b/fs/ocfs2/dcache.h
@@ -28,4 +28,31 @@
 
 extern struct dentry_operations ocfs2_dentry_ops;
 
+struct ocfs2_dentry_lock {
+        unsigned int            dl_count;
+        u64                     dl_parent_blkno;
+
+        /*
+         * The ocfs2_dentry_lock keeps an inode reference until
+         * dl_lockres has been destroyed. This is usually done in
+         * ->d_iput() anyway, so there should be minimal impact.
+         */
+        struct inode            *dl_inode;
+        struct ocfs2_lock_res   dl_lockres;
+};
+
+static inline void ocfs2_dentry_lock_put(struct ocfs2_super *osb,
+                                         struct ocfs2_dentry_lock *dl)
+{
+}
+
+static inline struct dentry *ocfs2_find_local_alias(struct inode *inode,
+                                                    u64 parent_blkno,
+                                                    int skip_unhashed)
+{
+        return NULL;
+}
+
+extern spinlock_t dentry_attach_lock;
+
 #endif /* OCFS2_DCACHE_H */
diff --git a/fs/ocfs2/dlmglue.c b/fs/ocfs2/dlmglue.c
index 20c6ca8ac7fd..764d15defd88 100644
--- a/fs/ocfs2/dlmglue.c
+++ b/fs/ocfs2/dlmglue.c
@@ -46,6 +46,7 @@
 #include "ocfs2.h"
 
 #include "alloc.h"
+#include "dcache.h"
 #include "dlmglue.h"
 #include "extent_map.h"
 #include "heartbeat.h"
@@ -69,6 +70,9 @@ struct ocfs2_mask_waiter {
 static void ocfs2_inode_ast_func(void *opaque);
 static void ocfs2_inode_bast_func(void *opaque,
                                   int level);
+static void ocfs2_dentry_ast_func(void *opaque);
+static void ocfs2_dentry_bast_func(void *opaque,
+                                  int level);
 static void ocfs2_super_ast_func(void *opaque);
 static void ocfs2_super_bast_func(void *opaque,
                                   int level);
@@ -76,32 +80,57 @@ static void ocfs2_rename_ast_func(void *opaque);
 static void ocfs2_rename_bast_func(void *opaque,
                                    int level);
 
+/*
+ * Return value from ocfs2_convert_worker_t functions.
+ *
+ * These control the precise actions of ocfs2_generic_unblock_lock()
+ * and ocfs2_process_blocked_lock()
+ *
+ */
+enum ocfs2_unblock_action {
+        UNBLOCK_CONTINUE        = 0, /* Continue downconvert */
+        UNBLOCK_CONTINUE_POST   = 1, /* Continue downconvert, fire
+                                      * ->post_unlock callback */
+        UNBLOCK_STOP_POST       = 2, /* Do not downconvert, fire
+                                      * ->post_unlock() callback. */
+};
+
+struct ocfs2_unblock_ctl {
+        int requeue;
+        enum ocfs2_unblock_action unblock_action;
+};
+
 /* so far, all locks have gotten along with the same unlock ast */
 static void ocfs2_unlock_ast_func(void *opaque,
                                   enum dlm_status status);
-static int ocfs2_do_unblock_meta(struct inode *inode,
-                                 int *requeue);
 static int ocfs2_unblock_meta(struct ocfs2_lock_res *lockres,
-                              int *requeue);
+                              struct ocfs2_unblock_ctl *ctl);
 static int ocfs2_unblock_data(struct ocfs2_lock_res *lockres,
-                              int *requeue);
+                              struct ocfs2_unblock_ctl *ctl);
 static int ocfs2_unblock_inode_lock(struct ocfs2_lock_res *lockres,
-                              int *requeue);
+                                    struct ocfs2_unblock_ctl *ctl);
+static int ocfs2_unblock_dentry_lock(struct ocfs2_lock_res *lockres,
+                                     struct ocfs2_unblock_ctl *ctl);
 static int ocfs2_unblock_osb_lock(struct ocfs2_lock_res *lockres,
-                                  int *requeue);
-typedef void (ocfs2_convert_worker_t)(struct ocfs2_lock_res *, int);
-static int ocfs2_generic_unblock_lock(struct ocfs2_super *osb,
-                                      struct ocfs2_lock_res *lockres,
-                                      int *requeue,
-                                      ocfs2_convert_worker_t *worker);
+                                  struct ocfs2_unblock_ctl *ctl);
+
+static void ocfs2_dentry_post_unlock(struct ocfs2_super *osb,
+                                     struct ocfs2_lock_res *lockres);
 
 struct ocfs2_lock_res_ops {
         void (*ast)(void *);
         void (*bast)(void *, int);
         void (*unlock_ast)(void *, enum dlm_status);
-        int  (*unblock)(struct ocfs2_lock_res *, int *);
+        int  (*unblock)(struct ocfs2_lock_res *, struct ocfs2_unblock_ctl *);
+        void (*post_unlock)(struct ocfs2_super *, struct ocfs2_lock_res *);
 };
 
+typedef int (ocfs2_convert_worker_t)(struct ocfs2_lock_res *, int);
+static int ocfs2_generic_unblock_lock(struct ocfs2_super *osb,
+                                      struct ocfs2_lock_res *lockres,
+                                      struct ocfs2_unblock_ctl *ctl,
+                                      ocfs2_convert_worker_t *worker);
+
 static struct ocfs2_lock_res_ops ocfs2_inode_rw_lops = {
         .ast            = ocfs2_inode_ast_func,
         .bast           = ocfs2_inode_bast_func,
@@ -116,9 +145,6 @@ static struct ocfs2_lock_res_ops ocfs2_inode_meta_lops = {
         .unblock        = ocfs2_unblock_meta,
 };
 
-static void ocfs2_data_convert_worker(struct ocfs2_lock_res *lockres,
-                                      int blocking);
-
 static struct ocfs2_lock_res_ops ocfs2_inode_data_lops = {
         .ast            = ocfs2_inode_ast_func,
         .bast           = ocfs2_inode_bast_func,
@@ -140,6 +166,14 @@ static struct ocfs2_lock_res_ops ocfs2_rename_lops = {
         .unblock        = ocfs2_unblock_osb_lock,
 };
 
+static struct ocfs2_lock_res_ops ocfs2_dentry_lops = {
+        .ast            = ocfs2_dentry_ast_func,
+        .bast           = ocfs2_dentry_bast_func,
+        .unlock_ast     = ocfs2_unlock_ast_func,
+        .unblock        = ocfs2_unblock_dentry_lock,
+        .post_unlock    = ocfs2_dentry_post_unlock,
+};
+
 static inline int ocfs2_is_inode_lock(struct ocfs2_lock_res *lockres)
 {
         return lockres->l_type == OCFS2_LOCK_TYPE_META ||
@@ -172,6 +206,13 @@ static inline struct inode *ocfs2_lock_res_inode(struct ocfs2_lock_res *lockres)
         return (struct inode *) lockres->l_priv;
 }
 
+static inline struct ocfs2_dentry_lock *ocfs2_lock_res_dl(struct ocfs2_lock_res *lockres)
+{
+        BUG_ON(lockres->l_type != OCFS2_LOCK_TYPE_DENTRY);
+
+        return (struct ocfs2_dentry_lock *)lockres->l_priv;
+}
+
 static int ocfs2_lock_create(struct ocfs2_super *osb,
                              struct ocfs2_lock_res *lockres,
                              int level,
@@ -204,22 +245,6 @@ static inline int ocfs2_can_downconvert_meta_lock(struct inode *inode,
                                                   struct ocfs2_lock_res *lockres,
                                                   int new_level);
 
-static char *ocfs2_lock_type_strings[] = {
-        [OCFS2_LOCK_TYPE_META] = "Meta",
-        [OCFS2_LOCK_TYPE_DATA] = "Data",
-        [OCFS2_LOCK_TYPE_SUPER] = "Super",
-        [OCFS2_LOCK_TYPE_RENAME] = "Rename",
-        /* Need to differntiate from [R]ename.. serializing writes is the
-         * important job it does, anyway. */
-        [OCFS2_LOCK_TYPE_RW] = "Write/Read",
-};
-
-static char *ocfs2_lock_type_string(enum ocfs2_lock_type type)
-{
-        mlog_bug_on_msg(type >= OCFS2_NUM_LOCK_TYPES, "%d\n", type);
-        return ocfs2_lock_type_strings[type];
-}
-
 static void ocfs2_build_lock_name(enum ocfs2_lock_type type,
                                   u64 blkno,
                                   u32 generation,
@@ -265,13 +290,9 @@ static void ocfs2_remove_lockres_tracking(struct ocfs2_lock_res *res)
 static void ocfs2_lock_res_init_common(struct ocfs2_super *osb,
                                        struct ocfs2_lock_res *res,
                                        enum ocfs2_lock_type type,
-                                       u64 blkno,
-                                       u32 generation,
                                        struct ocfs2_lock_res_ops *ops,
                                        void *priv)
 {
-        ocfs2_build_lock_name(type, blkno, generation, res->l_name);
-
         res->l_type          = type;
         res->l_ops           = ops;
         res->l_priv          = priv;
@@ -319,9 +340,59 @@ void ocfs2_inode_lock_res_init(struct ocfs2_lock_res *res,
                         break;
         };
 
-        ocfs2_lock_res_init_common(OCFS2_SB(inode->i_sb), res, type,
-                                   OCFS2_I(inode)->ip_blkno,
-                                   inode->i_generation, ops, inode);
+        ocfs2_build_lock_name(type, OCFS2_I(inode)->ip_blkno,
+                              inode->i_generation, res->l_name);
+        ocfs2_lock_res_init_common(OCFS2_SB(inode->i_sb), res, type, ops, inode);
+}
+
+static __u64 ocfs2_get_dentry_lock_ino(struct ocfs2_lock_res *lockres)
+{
+        __be64 inode_blkno_be;
+
+        memcpy(&inode_blkno_be, &lockres->l_name[OCFS2_DENTRY_LOCK_INO_START],
+               sizeof(__be64));
+
+        return be64_to_cpu(inode_blkno_be);
+}
+
+void ocfs2_dentry_lock_res_init(struct ocfs2_dentry_lock *dl,
+                                u64 parent, struct inode *inode)
+{
+        int len;
+        u64 inode_blkno = OCFS2_I(inode)->ip_blkno;
+        __be64 inode_blkno_be = cpu_to_be64(inode_blkno);
+        struct ocfs2_lock_res *lockres = &dl->dl_lockres;
+
+        ocfs2_lock_res_init_once(lockres);
+
+        /*
+         * Unfortunately, the standard lock naming scheme won't work
+         * here because we have two 16 byte values to use. Instead,
+         * we'll stuff the inode number as a binary value. We still
+         * want error prints to show something without garbling the
+         * display, so drop a null byte in there before the inode
+         * number. A future version of OCFS2 will likely use all
+         * binary lock names. The stringified names have been a
+         * tremendous aid in debugging, but now that the debugfs
+         * interface exists, we can mangle things there if need be.
+         *
+         * NOTE: We also drop the standard "pad" value (the total lock
+         * name size stays the same though - the last part is all
+         * zeros due to the memset in ocfs2_lock_res_init_once()
+         */
+        len = snprintf(lockres->l_name, OCFS2_DENTRY_LOCK_INO_START,
+                       "%c%016llx",
+                       ocfs2_lock_type_char(OCFS2_LOCK_TYPE_DENTRY),
+                       (long long)parent);
+
+        BUG_ON(len != (OCFS2_DENTRY_LOCK_INO_START - 1));
+
+        memcpy(&lockres->l_name[OCFS2_DENTRY_LOCK_INO_START], &inode_blkno_be,
+               sizeof(__be64));
+
+        ocfs2_lock_res_init_common(OCFS2_SB(inode->i_sb), lockres,
+                                   OCFS2_LOCK_TYPE_DENTRY, &ocfs2_dentry_lops,
+                                   dl);
 }
 
 static void ocfs2_super_lock_res_init(struct ocfs2_lock_res *res,
@@ -330,8 +401,9 @@ static void ocfs2_super_lock_res_init(struct ocfs2_lock_res *res,
         /* Superblock lockres doesn't come from a slab so we call init
          * once on it manually.  */
         ocfs2_lock_res_init_once(res);
+        ocfs2_build_lock_name(OCFS2_LOCK_TYPE_SUPER, OCFS2_SUPER_BLOCK_BLKNO,
+                              0, res->l_name);
         ocfs2_lock_res_init_common(osb, res, OCFS2_LOCK_TYPE_SUPER,
-                                   OCFS2_SUPER_BLOCK_BLKNO, 0,
                                    &ocfs2_super_lops, osb);
 }
 
@@ -341,7 +413,8 @@ static void ocfs2_rename_lock_res_init(struct ocfs2_lock_res *res,
         /* Rename lockres doesn't come from a slab so we call init
          * once on it manually.  */
         ocfs2_lock_res_init_once(res);
-        ocfs2_lock_res_init_common(osb, res, OCFS2_LOCK_TYPE_RENAME, 0, 0,
+        ocfs2_build_lock_name(OCFS2_LOCK_TYPE_RENAME, 0, 0, res->l_name);
+        ocfs2_lock_res_init_common(osb, res, OCFS2_LOCK_TYPE_RENAME,
                                    &ocfs2_rename_lops, osb);
 }
 
@@ -627,9 +700,10 @@ static void ocfs2_generic_bast_func(struct ocfs2_super *osb,
                 ocfs2_schedule_blocked_lock(osb, lockres);
         spin_unlock_irqrestore(&lockres->l_lock, flags);
 
+        wake_up(&lockres->l_event);
+
         ocfs2_kick_vote_thread(osb);
 
-        wake_up(&lockres->l_event);
         mlog_exit_void();
 }
 
@@ -690,9 +764,9 @@ static void ocfs2_generic_ast_func(struct ocfs2_lock_res *lockres,
         /* set it to something invalid so if we get called again we
          * can catch it. */
         lockres->l_action = OCFS2_AST_INVALID;
-        spin_unlock_irqrestore(&lockres->l_lock, flags);
 
         wake_up(&lockres->l_event);
+        spin_unlock_irqrestore(&lockres->l_lock, flags);
 }
 
 static void ocfs2_super_ast_func(void *opaque)
@@ -757,6 +831,27 @@ static void ocfs2_rename_bast_func(void *opaque,
         mlog_exit_void();
 }
 
+static void ocfs2_dentry_ast_func(void *opaque)
+{
+        struct ocfs2_lock_res *lockres = opaque;
+
+        BUG_ON(!lockres);
+
+        ocfs2_generic_ast_func(lockres, 1);
+}
+
+static void ocfs2_dentry_bast_func(void *opaque, int level)
+{
+        struct ocfs2_lock_res *lockres = opaque;
+        struct ocfs2_dentry_lock *dl = lockres->l_priv;
+        struct ocfs2_super *osb = OCFS2_SB(dl->dl_inode->i_sb);
+
+        mlog(0, "Dentry bast: level: %d, name: %s\n", level,
+             lockres->l_name);
+
+        ocfs2_generic_bast_func(osb, lockres, level);
+}
+
 static inline void ocfs2_recover_from_dlm_error(struct ocfs2_lock_res *lockres,
                                                 int convert)
 {
@@ -1076,10 +1171,11 @@ static void ocfs2_cluster_unlock(struct ocfs2_super *osb,
         mlog_exit_void();
 }
 
-static int ocfs2_create_new_inode_lock(struct inode *inode,
-                                       struct ocfs2_lock_res *lockres)
+int ocfs2_create_new_lock(struct ocfs2_super *osb,
+                          struct ocfs2_lock_res *lockres,
+                          int ex)
 {
-        struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
+        int level =  ex ? LKM_EXMODE : LKM_PRMODE;
         unsigned long flags;
 
         spin_lock_irqsave(&lockres->l_lock, flags);
@@ -1087,7 +1183,7 @@ static int ocfs2_create_new_inode_lock(struct inode *inode,
         lockres_or_flags(lockres, OCFS2_LOCK_LOCAL);
         spin_unlock_irqrestore(&lockres->l_lock, flags);
 
-        return ocfs2_lock_create(osb, lockres, LKM_EXMODE, LKM_LOCAL);
+        return ocfs2_lock_create(osb, lockres, level, LKM_LOCAL);
 }
 
 /* Grants us an EX lock on the data and metadata resources, skipping
@@ -1099,6 +1195,7 @@ static int ocfs2_create_new_inode_lock(struct inode *inode,
 int ocfs2_create_new_inode_locks(struct inode *inode)
 {
         int ret;
+        struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
 
         BUG_ON(!inode);
         BUG_ON(!ocfs2_inode_is_new(inode));
@@ -1115,22 +1212,19 @@ int ocfs2_create_new_inode_locks(struct inode *inode)
          * on a resource which has an invalid one -- we'll set it
          * valid when we release the EX. */
 
-        ret = ocfs2_create_new_inode_lock(inode,
-                                          &OCFS2_I(inode)->ip_rw_lockres);
+        ret = ocfs2_create_new_lock(osb, &OCFS2_I(inode)->ip_rw_lockres, 1);
         if (ret) {
                 mlog_errno(ret);
                 goto bail;
         }
 
-        ret = ocfs2_create_new_inode_lock(inode,
-                                          &OCFS2_I(inode)->ip_meta_lockres);
+        ret = ocfs2_create_new_lock(osb, &OCFS2_I(inode)->ip_meta_lockres, 1);
         if (ret) {
                 mlog_errno(ret);
                 goto bail;
         }
 
-        ret = ocfs2_create_new_inode_lock(inode,
-                                          &OCFS2_I(inode)->ip_data_lockres);
+        ret = ocfs2_create_new_lock(osb, &OCFS2_I(inode)->ip_data_lockres, 1);
         if (ret) {
                 mlog_errno(ret);
                 goto bail;
@@ -1809,6 +1903,34 @@ void ocfs2_rename_unlock(struct ocfs2_super *osb)
         ocfs2_cluster_unlock(osb, lockres, LKM_EXMODE);
 }
 
+int ocfs2_dentry_lock(struct dentry *dentry, int ex)
+{
+        int ret;
+        int level = ex ? LKM_EXMODE : LKM_PRMODE;
+        struct ocfs2_dentry_lock *dl = dentry->d_fsdata;
+        struct ocfs2_super *osb = OCFS2_SB(dentry->d_sb);
+
+        BUG_ON(!dl);
+
+        if (ocfs2_is_hard_readonly(osb))
+                return -EROFS;
+
+        ret = ocfs2_cluster_lock(osb, &dl->dl_lockres, level, 0, 0);
+        if (ret < 0)
+                mlog_errno(ret);
+
+        return ret;
+}
+
+void ocfs2_dentry_unlock(struct dentry *dentry, int ex)
+{
+        int level = ex ? LKM_EXMODE : LKM_PRMODE;
+        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);
+}
+
 /* Reference counting of the dlm debug structure. We want this because
  * open references on the debug inodes can live on after a mount, so
  * we can't rely on the ocfs2_super to always exist. */
@@ -1939,9 +2061,16 @@ static int ocfs2_dlm_seq_show(struct seq_file *m, void *v)
         if (!lockres)
                 return -EINVAL;
 
-        seq_printf(m, "0x%x\t"
-                   "%.*s\t"
-                   "%d\t"
+        seq_printf(m, "0x%x\t", OCFS2_DLM_DEBUG_STR_VERSION);
+
+        if (lockres->l_type == OCFS2_LOCK_TYPE_DENTRY)
+                seq_printf(m, "%.*s%08x\t", OCFS2_DENTRY_LOCK_INO_START - 1,
+                           lockres->l_name,
+                           (unsigned int)ocfs2_get_dentry_lock_ino(lockres));
+        else
+                seq_printf(m, "%.*s\t", OCFS2_LOCK_ID_MAX_LEN, lockres->l_name);
+
+        seq_printf(m, "%d\t"
                    "0x%lx\t"
                    "0x%x\t"
                    "0x%x\t"
@@ -1949,8 +2078,6 @@ static int ocfs2_dlm_seq_show(struct seq_file *m, void *v)
                    "%u\t"
                    "%d\t"
                    "%d\t",
-                   OCFS2_DLM_DEBUG_STR_VERSION,
-                   OCFS2_LOCK_ID_MAX_LEN, lockres->l_name,
                    lockres->l_level,
                    lockres->l_flags,
                    lockres->l_action,
@@ -2311,25 +2438,21 @@ void ocfs2_mark_lockres_freeing(struct ocfs2_lock_res *lockres)
         spin_unlock_irqrestore(&lockres->l_lock, flags);
 }
 
-static void ocfs2_drop_osb_locks(struct ocfs2_super *osb)
+void ocfs2_simple_drop_lockres(struct ocfs2_super *osb,
+                               struct ocfs2_lock_res *lockres)
 {
-        int status;
-
-        mlog_entry_void();
-
-        ocfs2_mark_lockres_freeing(&osb->osb_super_lockres);
-
-        status = ocfs2_drop_lock(osb, &osb->osb_super_lockres, NULL);
-        if (status < 0)
-                mlog_errno(status);
-
-        ocfs2_mark_lockres_freeing(&osb->osb_rename_lockres);
+        int ret;
 
-        status = ocfs2_drop_lock(osb, &osb->osb_rename_lockres, NULL);
-        if (status < 0)
-                mlog_errno(status);
+        ocfs2_mark_lockres_freeing(lockres);
+        ret = ocfs2_drop_lock(osb, lockres, NULL);
+        if (ret)
+                mlog_errno(ret);
+}
 
-        mlog_exit(status);
+static void ocfs2_drop_osb_locks(struct ocfs2_super *osb)
+{
+        ocfs2_simple_drop_lockres(osb, &osb->osb_super_lockres);
+        ocfs2_simple_drop_lockres(osb, &osb->osb_rename_lockres);
 }
 
 static void ocfs2_meta_pre_drop(struct ocfs2_lock_res *lockres, void *data)
@@ -2599,7 +2722,7 @@ leave:
 
 static int ocfs2_generic_unblock_lock(struct ocfs2_super *osb,
                                       struct ocfs2_lock_res *lockres,
-                                      int *requeue,
+                                      struct ocfs2_unblock_ctl *ctl,
                                       ocfs2_convert_worker_t *worker)
 {
         unsigned long flags;
@@ -2615,7 +2738,7 @@ static int ocfs2_generic_unblock_lock(struct ocfs2_super *osb,
 
 recheck:
         if (lockres->l_flags & OCFS2_LOCK_BUSY) {
-                *requeue = 1;
+                ctl->requeue = 1;
                 ret = ocfs2_prepare_cancel_convert(osb, lockres);
                 spin_unlock_irqrestore(&lockres->l_lock, flags);
                 if (ret) {
@@ -2631,7 +2754,7 @@ recheck:
         if ((lockres->l_blocking == LKM_EXMODE)
             && (lockres->l_ex_holders || lockres->l_ro_holders)) {
                 spin_unlock_irqrestore(&lockres->l_lock, flags);
-                *requeue = 1;
+                ctl->requeue = 1;
                 ret = 0;
                 goto leave;
         }
@@ -2641,7 +2764,7 @@ recheck:
         if (lockres->l_blocking == LKM_PRMODE &&
             lockres->l_ex_holders) {
                 spin_unlock_irqrestore(&lockres->l_lock, flags);
-                *requeue = 1;
+                ctl->requeue = 1;
                 ret = 0;
                 goto leave;
         }
@@ -2659,7 +2782,10 @@ recheck:
         blocking = lockres->l_blocking;
         spin_unlock_irqrestore(&lockres->l_lock, flags);
 
-        worker(lockres, blocking);
+        ctl->unblock_action = worker(lockres, blocking);
+
+        if (ctl->unblock_action == UNBLOCK_STOP_POST)
+                goto leave;
 
         spin_lock_irqsave(&lockres->l_lock, flags);
         if (blocking != lockres->l_blocking) {
@@ -2669,7 +2795,7 @@ recheck:
         }
 
 downconvert:
-        *requeue = 0;
+        ctl->requeue = 0;
         new_level = ocfs2_highest_compat_lock_level(lockres->l_blocking);
 
         ocfs2_prepare_downconvert(lockres, new_level);
@@ -2680,14 +2806,12 @@ leave:
         return ret;
 }
 
-static void ocfs2_data_convert_worker(struct ocfs2_lock_res *lockres,
-                                      int blocking)
+static int ocfs2_data_convert_worker(struct ocfs2_lock_res *lockres,
+                                     int blocking)
 {
         struct inode *inode;
         struct address_space *mapping;
 
-        mlog_entry_void();
-
         inode = ocfs2_lock_res_inode(lockres);
         mapping = inode->i_mapping;
 
@@ -2708,11 +2832,11 @@ static void ocfs2_data_convert_worker(struct ocfs2_lock_res *lockres,
                 filemap_fdatawait(mapping);
         }
 
-        mlog_exit_void();
+        return UNBLOCK_CONTINUE;
 }
 
 int ocfs2_unblock_data(struct ocfs2_lock_res *lockres,
-                       int *requeue)
+                       struct ocfs2_unblock_ctl *ctl)
 {
         int status;
         struct inode *inode;
@@ -2726,22 +2850,20 @@ int ocfs2_unblock_data(struct ocfs2_lock_res *lockres,
         mlog(0, "unblock inode %llu\n",
              (unsigned long long)OCFS2_I(inode)->ip_blkno);
 
-        status = ocfs2_generic_unblock_lock(osb,
-                                            lockres,
-                                            requeue,
+        status = ocfs2_generic_unblock_lock(osb, lockres, ctl,
                                             ocfs2_data_convert_worker);
         if (status < 0)
                 mlog_errno(status);
 
         mlog(0, "inode %llu, requeue = %d\n",
-             (unsigned long long)OCFS2_I(inode)->ip_blkno, *requeue);
+             (unsigned long long)OCFS2_I(inode)->ip_blkno, ctl->requeue);
 
         mlog_exit(status);
         return status;
 }
 
 static int ocfs2_unblock_inode_lock(struct ocfs2_lock_res *lockres,
-                                    int *requeue)
+                                    struct ocfs2_unblock_ctl *ctl)
 {
         int status;
         struct inode *inode;
@@ -2753,9 +2875,7 @@ static int ocfs2_unblock_inode_lock(struct ocfs2_lock_res *lockres,
         inode  = ocfs2_lock_res_inode(lockres);
 
         status = ocfs2_generic_unblock_lock(OCFS2_SB(inode->i_sb),
-                                            lockres,
-                                            requeue,
-                                            NULL);
+                                            lockres, ctl, NULL);
         if (status < 0)
                 mlog_errno(status);
 
@@ -2763,9 +2883,8 @@ static int ocfs2_unblock_inode_lock(struct ocfs2_lock_res *lockres,
         return status;
 }
 
-
-int ocfs2_unblock_meta(struct ocfs2_lock_res *lockres,
-                       int *requeue)
+static int ocfs2_unblock_meta(struct ocfs2_lock_res *lockres,
+                              struct ocfs2_unblock_ctl *ctl)
 {
         int status;
         struct inode *inode;
@@ -2777,21 +2896,165 @@ int ocfs2_unblock_meta(struct ocfs2_lock_res *lockres,
         mlog(0, "unblock inode %llu\n",
              (unsigned long long)OCFS2_I(inode)->ip_blkno);
 
-        status = ocfs2_do_unblock_meta(inode, requeue);
+        status = ocfs2_do_unblock_meta(inode, &ctl->requeue);
         if (status < 0)
                 mlog_errno(status);
 
         mlog(0, "inode %llu, requeue = %d\n",
-             (unsigned long long)OCFS2_I(inode)->ip_blkno, *requeue);
+             (unsigned long long)OCFS2_I(inode)->ip_blkno, ctl->requeue);
 
         mlog_exit(status);
         return status;
 }
 
+/*
+ * Does the final reference drop on our dentry lock. Right now this
+ * happens in the vote thread, but we could choose to simplify the
+ * dlmglue API and push these off to the ocfs2_wq in the future.
+ */
+static void ocfs2_dentry_post_unlock(struct ocfs2_super *osb,
+                                     struct ocfs2_lock_res *lockres)
+{
+        struct ocfs2_dentry_lock *dl = ocfs2_lock_res_dl(lockres);
+        ocfs2_dentry_lock_put(osb, dl);
+}
+
+/*
+ * d_delete() matching dentries before the lock downconvert.
+ *
+ * At this point, any process waiting to destroy the
+ * dentry_lock due to last ref count is stopped by the
+ * OCFS2_LOCK_QUEUED flag.
+ *
+ * We have two potential problems
+ *
+ * 1) If we do the last reference drop on our dentry_lock (via dput)
+ *    we'll wind up in ocfs2_release_dentry_lock(), waiting on
+ *    the downconvert to finish. Instead we take an elevated
+ *    reference and push the drop until after we've completed our
+ *    unblock processing.
+ *
+ * 2) There might be another process with a final reference,
+ *    waiting on us to finish processing. If this is the case, we
+ *    detect it and exit out - there's no more dentries anyway.
+ */
+static int ocfs2_dentry_convert_worker(struct ocfs2_lock_res *lockres,
+                                       int blocking)
+{
+        struct ocfs2_dentry_lock *dl = ocfs2_lock_res_dl(lockres);
+        struct ocfs2_inode_info *oi = OCFS2_I(dl->dl_inode);
+        struct dentry *dentry;
+        unsigned long flags;
+        int extra_ref = 0;
+
+        /*
+         * This node is blocking another node from getting a read
+         * lock. This happens when we've renamed within a
+         * directory. We've forced the other nodes to d_delete(), but
+         * we never actually dropped our lock because it's still
+         * valid. The downconvert code will retain a PR for this node,
+         * so there's no further work to do.
+         */
+        if (blocking == LKM_PRMODE)
+                return UNBLOCK_CONTINUE;
+
+        /*
+         * Mark this inode as potentially orphaned. The code in
+         * ocfs2_delete_inode() will figure out whether it actually
+         * needs to be freed or not.
+         */
+        spin_lock(&oi->ip_lock);
+        oi->ip_flags |= OCFS2_INODE_MAYBE_ORPHANED;
+        spin_unlock(&oi->ip_lock);
+
+        /*
+         * Yuck. We need to make sure however that the check of
+         * OCFS2_LOCK_FREEING and the extra reference are atomic with
+         * respect to a reference decrement or the setting of that
+         * flag.
+         */
+        spin_lock_irqsave(&lockres->l_lock, flags);
+        spin_lock(&dentry_attach_lock);
+        if (!(lockres->l_flags & OCFS2_LOCK_FREEING)
+            && dl->dl_count) {
+                dl->dl_count++;
+                extra_ref = 1;
+        }
+        spin_unlock(&dentry_attach_lock);
+        spin_unlock_irqrestore(&lockres->l_lock, flags);
+
+        mlog(0, "extra_ref = %d\n", extra_ref);
+
+        /*
+         * We have a process waiting on us in ocfs2_dentry_iput(),
+         * which means we can't have any more outstanding
+         * aliases. There's no need to do any more work.
+         */
+        if (!extra_ref)
+                return UNBLOCK_CONTINUE;
+
+        spin_lock(&dentry_attach_lock);
+        while (1) {
+                dentry = ocfs2_find_local_alias(dl->dl_inode,
+                                                dl->dl_parent_blkno, 1);
+                if (!dentry)
+                        break;
+                spin_unlock(&dentry_attach_lock);
+
+                mlog(0, "d_delete(%.*s);\n", dentry->d_name.len,
+                     dentry->d_name.name);
+
+                /*
+                 * The following dcache calls may do an
+                 * iput(). Normally we don't want that from the
+                 * downconverting thread, but in this case it's ok
+                 * because the requesting node already has an
+                 * exclusive lock on the inode, so it can't be queued
+                 * for a downconvert.
+                 */
+                d_delete(dentry);
+                dput(dentry);
+
+                spin_lock(&dentry_attach_lock);
+        }
+        spin_unlock(&dentry_attach_lock);
+
+        /*
+         * If we are the last holder of this dentry lock, there is no
+         * reason to downconvert so skip straight to the unlock.
+         */
+        if (dl->dl_count == 1)
+                return UNBLOCK_STOP_POST;
+
+        return UNBLOCK_CONTINUE_POST;
+}
+
+static int ocfs2_unblock_dentry_lock(struct ocfs2_lock_res *lockres,
+                                     struct ocfs2_unblock_ctl *ctl)
+{
+        int ret;
+        struct ocfs2_dentry_lock *dl = ocfs2_lock_res_dl(lockres);
+        struct ocfs2_super *osb = OCFS2_SB(dl->dl_inode->i_sb);
+
+        mlog(0, "unblock dentry lock: %llu\n",
+             (unsigned long long)OCFS2_I(dl->dl_inode)->ip_blkno);
+
+        ret = ocfs2_generic_unblock_lock(osb,
+                                         lockres,
+                                         ctl,
+                                         ocfs2_dentry_convert_worker);
+        if (ret < 0)
+                mlog_errno(ret);
+
+        mlog(0, "requeue = %d, post = %d\n", ctl->requeue, ctl->unblock_action);
+
+        return ret;
+}
+
 /* Generic unblock function for any lockres whose private data is an
  * ocfs2_super pointer. */
 static int ocfs2_unblock_osb_lock(struct ocfs2_lock_res *lockres,
-                                  int *requeue)
+                                  struct ocfs2_unblock_ctl *ctl)
 {
         int status;
         struct ocfs2_super *osb;
@@ -2804,7 +3067,7 @@ static int ocfs2_unblock_osb_lock(struct ocfs2_lock_res *lockres,
 
         status = ocfs2_generic_unblock_lock(osb,
                                             lockres,
-                                            requeue,
+                                            ctl,
                                             NULL);
         if (status < 0)
                 mlog_errno(status);
@@ -2817,7 +3080,7 @@ void ocfs2_process_blocked_lock(struct ocfs2_super *osb,
                                 struct ocfs2_lock_res *lockres)
 {
         int status;
-        int requeue = 0;
+        struct ocfs2_unblock_ctl ctl = {0, 0,};
         unsigned long flags;
 
         /* Our reference to the lockres in this function can be
@@ -2842,21 +3105,25 @@ void ocfs2_process_blocked_lock(struct ocfs2_super *osb,
                 goto unqueue;
         spin_unlock_irqrestore(&lockres->l_lock, flags);
 
-        status = lockres->l_ops->unblock(lockres, &requeue);
+        status = lockres->l_ops->unblock(lockres, &ctl);
         if (status < 0)
                 mlog_errno(status);
 
         spin_lock_irqsave(&lockres->l_lock, flags);
 unqueue:
-        if (lockres->l_flags & OCFS2_LOCK_FREEING || !requeue) {
+        if (lockres->l_flags & OCFS2_LOCK_FREEING || !ctl.requeue) {
                 lockres_clear_flags(lockres, OCFS2_LOCK_QUEUED);
         } else
                 ocfs2_schedule_blocked_lock(osb, lockres);
 
         mlog(0, "lockres %s, requeue = %s.\n", lockres->l_name,
-             requeue ? "yes" : "no");
+             ctl.requeue ? "yes" : "no");
         spin_unlock_irqrestore(&lockres->l_lock, flags);
 
+        if (ctl.unblock_action != UNBLOCK_CONTINUE
+            && lockres->l_ops->post_unlock)
+                lockres->l_ops->post_unlock(osb, lockres);
+
         mlog_exit_void();
 }
 
diff --git a/fs/ocfs2/dlmglue.h b/fs/ocfs2/dlmglue.h
index 243ae862ece5..340251567e99 100644
--- a/fs/ocfs2/dlmglue.h
+++ b/fs/ocfs2/dlmglue.h
@@ -27,6 +27,8 @@
 #ifndef DLMGLUE_H
 #define DLMGLUE_H
 
+#include "dcache.h"
+
 #define OCFS2_LVB_VERSION 3
 
 struct ocfs2_meta_lvb {
@@ -58,8 +60,12 @@ void ocfs2_lock_res_init_once(struct ocfs2_lock_res *res);
 void ocfs2_inode_lock_res_init(struct ocfs2_lock_res *res,
                                enum ocfs2_lock_type type,
                                struct inode *inode);
+void ocfs2_dentry_lock_res_init(struct ocfs2_dentry_lock *dl,
+                                u64 parent, struct inode *inode);
 void ocfs2_lock_res_free(struct ocfs2_lock_res *res);
 int ocfs2_create_new_inode_locks(struct inode *inode);
+int ocfs2_create_new_lock(struct ocfs2_super *osb,
+                          struct ocfs2_lock_res *lockres, int ex);
 int ocfs2_drop_inode_locks(struct inode *inode);
 int ocfs2_data_lock_full(struct inode *inode,
                          int write,
@@ -93,7 +99,12 @@ void ocfs2_super_unlock(struct ocfs2_super *osb,
                         int ex);
 int ocfs2_rename_lock(struct ocfs2_super *osb);
 void ocfs2_rename_unlock(struct ocfs2_super *osb);
+int ocfs2_dentry_lock(struct dentry *dentry, int ex);
+void ocfs2_dentry_unlock(struct dentry *dentry, int ex);
+
 void ocfs2_mark_lockres_freeing(struct ocfs2_lock_res *lockres);
+void ocfs2_simple_drop_lockres(struct ocfs2_super *osb,
+                               struct ocfs2_lock_res *lockres);
 
 /* for the vote thread */
 void ocfs2_process_blocked_lock(struct ocfs2_super *osb,
diff --git a/fs/ocfs2/ocfs2_lockid.h b/fs/ocfs2/ocfs2_lockid.h
index 7dd9e1e705b0..4d5d5655c185 100644
--- a/fs/ocfs2/ocfs2_lockid.h
+++ b/fs/ocfs2/ocfs2_lockid.h
@@ -35,12 +35,15 @@
 #define OCFS2_LOCK_ID_MAX_LEN  32
 #define OCFS2_LOCK_ID_PAD "000000"
 
+#define OCFS2_DENTRY_LOCK_INO_START 18
+
 enum ocfs2_lock_type {
         OCFS2_LOCK_TYPE_META = 0,
         OCFS2_LOCK_TYPE_DATA,
         OCFS2_LOCK_TYPE_SUPER,
         OCFS2_LOCK_TYPE_RENAME,
         OCFS2_LOCK_TYPE_RW,
+        OCFS2_LOCK_TYPE_DENTRY,
         OCFS2_NUM_LOCK_TYPES
 };
 
@@ -63,6 +66,9 @@ static inline char ocfs2_lock_type_char(enum ocfs2_lock_type type)
                 case OCFS2_LOCK_TYPE_RW:
                         c = 'W';
                         break;
+                case OCFS2_LOCK_TYPE_DENTRY:
+                        c = 'N';
+                        break;
                 default:
                         c = '\0';
         }
@@ -70,4 +76,23 @@ static inline char ocfs2_lock_type_char(enum ocfs2_lock_type type)
         return c;
 }
 
+static char *ocfs2_lock_type_strings[] = {
+        [OCFS2_LOCK_TYPE_META] = "Meta",
+        [OCFS2_LOCK_TYPE_DATA] = "Data",
+        [OCFS2_LOCK_TYPE_SUPER] = "Super",
+        [OCFS2_LOCK_TYPE_RENAME] = "Rename",
+        /* Need to differntiate from [R]ename.. serializing writes is the
+         * important job it does, anyway. */
+        [OCFS2_LOCK_TYPE_RW] = "Write/Read",
+        [OCFS2_LOCK_TYPE_DENTRY] = "Dentry",
+};
+
+static inline const char *ocfs2_lock_type_string(enum ocfs2_lock_type type)
+{
+#ifdef __KERNEL__
+        mlog_bug_on_msg(type >= OCFS2_NUM_LOCK_TYPES, "%d\n", type);
+#endif
+        return ocfs2_lock_type_strings[type];
+}
+
 #endif  /* OCFS2_LOCKID_H */