jdb/jbd2: factor out common functions from the jbd[2] header files

The state bits and the lock functions of jbd and jbd2 are
identical.  Share them.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>

1 files changed, 68 insertions, 0 deletions

diff --git a/include/linux/jbd_common.h b/include/linux/jbd_common.h
new file mode 100644
index 000000000000..6230f8556a4e
--- /dev/null
+++ b/include/linux/jbd_common.h
@@ -0,0 +1,68 @@
+#ifndef _LINUX_JBD_STATE_H
+#define _LINUX_JBD_STATE_H
+
+enum jbd_state_bits {
+        BH_JBD                  /* Has an attached ext3 journal_head */
+          = BH_PrivateStart,
+        BH_JWrite,              /* Being written to log (@@@ DEBUGGING) */
+        BH_Freed,               /* Has been freed (truncated) */
+        BH_Revoked,             /* Has been revoked from the log */
+        BH_RevokeValid,         /* Revoked flag is valid */
+        BH_JBDDirty,            /* Is dirty but journaled */
+        BH_State,               /* Pins most journal_head state */
+        BH_JournalHead,         /* Pins bh->b_private and jh->b_bh */
+        BH_Unshadow,            /* Dummy bit, for BJ_Shadow wakeup filtering */
+        BH_JBDPrivateStart,     /* First bit available for private use by FS */
+};
+
+BUFFER_FNS(JBD, jbd)
+BUFFER_FNS(JWrite, jwrite)
+BUFFER_FNS(JBDDirty, jbddirty)
+TAS_BUFFER_FNS(JBDDirty, jbddirty)
+BUFFER_FNS(Revoked, revoked)
+TAS_BUFFER_FNS(Revoked, revoked)
+BUFFER_FNS(RevokeValid, revokevalid)
+TAS_BUFFER_FNS(RevokeValid, revokevalid)
+BUFFER_FNS(Freed, freed)
+
+static inline struct buffer_head *jh2bh(struct journal_head *jh)
+{
+        return jh->b_bh;
+}
+
+static inline struct journal_head *bh2jh(struct buffer_head *bh)
+{
+        return bh->b_private;
+}
+
+static inline void jbd_lock_bh_state(struct buffer_head *bh)
+{
+        bit_spin_lock(BH_State, &bh->b_state);
+}
+
+static inline int jbd_trylock_bh_state(struct buffer_head *bh)
+{
+        return bit_spin_trylock(BH_State, &bh->b_state);
+}
+
+static inline int jbd_is_locked_bh_state(struct buffer_head *bh)
+{
+        return bit_spin_is_locked(BH_State, &bh->b_state);
+}
+
+static inline void jbd_unlock_bh_state(struct buffer_head *bh)
+{
+        bit_spin_unlock(BH_State, &bh->b_state);
+}
+
+static inline void jbd_lock_bh_journal_head(struct buffer_head *bh)
+{
+        bit_spin_lock(BH_JournalHead, &bh->b_state);
+}
+
+static inline void jbd_unlock_bh_journal_head(struct buffer_head *bh)
+{
+        bit_spin_unlock(BH_JournalHead, &bh->b_state);
+}
+
+#endif