Rebase master to b117

[zfs.git] / module / zfs / include / sys / zil.h

diff --git a/module/zfs/include/sys/zil.h b/module/zfs/include/sys/zil.h
index 4d02d14..2aff8cd 100644 (file)
--- a/module/zfs/include/sys/zil.h
+++ b/module/zfs/include/sys/zil.h
@@ -19,7 +19,7 @@
  * CDDL HEADER END
  */
 /*
- * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
+ * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
  * Use is subject to license terms.
  */
 
@@ -56,10 +56,16 @@ typedef struct zil_header {
        uint64_t zh_replay_seq; /* highest replayed sequence number */
        blkptr_t zh_log;        /* log chain */
        uint64_t zh_claim_seq;  /* highest claimed sequence number */
-       uint64_t zh_pad[5];
+       uint64_t zh_flags;      /* header flags */
+       uint64_t zh_pad[4];
 } zil_header_t;
 
 /*
+ * zh_flags bit settings
+ */
+#define        ZIL_REPLAY_NEEDED 0x1   /* replay needed - internal only */
+
+/*
  * Log block trailer - structure at the end of the header and each log block
  *
  * The zit_bt contains a zbt_cksum which for the intent log is
@@ -299,7 +305,27 @@ typedef struct {
  */
 
 /*
- * ZFS intent log transaction structure
+ * Writes are handled in three different ways:
+ *
+ * WR_INDIRECT:
+ *    In this mode, if we need to commit the write later, then the block
+ *    is immediately written into the file system (using dmu_sync),
+ *    and a pointer to the block is put into the log record.
+ *    When the txg commits the block is linked in.
+ *    This saves additionally writing the data into the log record.
+ *    There are a few requirements for this to occur:
+ *     - write is greater than zfs/zvol_immediate_write_sz
+ *     - not using slogs (as slogs are assumed to always be faster
+ *       than writing into the main pool)
+ *     - the write occupies only one block
+ * WR_COPIED:
+ *    If we know we'll immediately be committing the
+ *    transaction (FSYNC or FDSYNC), the we allocate a larger
+ *    log record here for the data and copy the data in.
+ * WR_NEED_COPY:
+ *    Otherwise we don't allocate a buffer, and *if* we need to
+ *    flush the write later then a buffer is allocated and
+ *    we retrieve the data using the dmu.
  */
 typedef enum {
        WR_INDIRECT,    /* indirect - a large write (dmu_sync() data */
@@ -335,7 +361,6 @@ typedef void zil_parse_blk_func_t(zilog_t *zilog, blkptr_t *bp, void *arg,
 typedef void zil_parse_lr_func_t(zilog_t *zilog, lr_t *lr, void *arg,
     uint64_t txg);
 typedef int zil_replay_func_t();
-typedef void zil_replay_cleaner_t();
 typedef int zil_get_data_t(void *arg, lr_write_t *lr, char *dbuf, zio_t *zio);
 
 extern uint64_t        zil_parse(zilog_t *zilog, zil_parse_blk_func_t *parse_blk_func,
@@ -350,9 +375,8 @@ extern void zil_free(zilog_t *zilog);
 extern zilog_t *zil_open(objset_t *os, zil_get_data_t *get_data);
 extern void    zil_close(zilog_t *zilog);
 
-extern void    zil_replay(objset_t *os, void *arg, uint64_t *txgp,
-    zil_replay_func_t *replay_func[TX_MAX_TYPE],
-    zil_replay_cleaner_t *replay_cleaner);
+extern void    zil_replay(objset_t *os, void *arg,
+    zil_replay_func_t *replay_func[TX_MAX_TYPE]);
 extern void    zil_destroy(zilog_t *zilog, boolean_t keep_first);
 extern void    zil_rollback_destroy(zilog_t *zilog, dmu_tx_t *tx);
 
@@ -361,9 +385,9 @@ extern uint64_t zil_itx_assign(zilog_t *zilog, itx_t *itx, dmu_tx_t *tx);
 
 extern void    zil_commit(zilog_t *zilog, uint64_t seq, uint64_t oid);
 
+extern int     zil_vdev_offline(char *osname, void *txarg);
 extern int     zil_claim(char *osname, void *txarg);
 extern int     zil_check_log_chain(char *osname, void *txarg);
-extern int     zil_clear_log_chain(char *osname, void *txarg);
 extern void    zil_sync(zilog_t *zilog, dmu_tx_t *tx);
 extern void    zil_clean(zilog_t *zilog);
 extern int     zil_is_committed(zilog_t *zilog);