X-Git-Url: http://ftp.safe.ca/?a=blobdiff_plain;f=fs%2Fgfs2%2Flog.c;h=98918a756410ca576f3fec0ba49fa8a82869033f;hb=4f6b828837b4e3836f2c9ac2f0eab9773b6c1327;hp=e6acb41332e70364c124a45f4463674a1bb54b17;hpb=f55ab26a8f92a23988c3e6da28dae4741933a4e2;p=safe%2Fjmp%2Flinux-2.6

diff --git a/fs/gfs2/log.c b/fs/gfs2/log.c
index e6acb41..98918a7 100644
--- a/fs/gfs2/log.c
+++ b/fs/gfs2/log.c
@@ -1,10 +1,10 @@
 /*
  * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
- * Copyright (C) 2004-2005 Red Hat, Inc.  All rights reserved.
+ * Copyright (C) 2004-2007 Red Hat, Inc.  All rights reserved.
  *
  * This copyrighted material is made available to anyone wishing to use,
  * modify, copy, or redistribute it subject to the terms and conditions
- * of the GNU General Public License v.2.
+ * of the GNU General Public License version 2.
  */
 
 #include <linux/sched.h>
@@ -12,49 +12,25 @@
 #include <linux/spinlock.h>
 #include <linux/completion.h>
 #include <linux/buffer_head.h>
-#include <asm/semaphore.h>
+#include <linux/gfs2_ondisk.h>
+#include <linux/crc32.h>
+#include <linux/delay.h>
+#include <linux/kthread.h>
+#include <linux/freezer.h>
+#include <linux/bio.h>
 
 #include "gfs2.h"
+#include "incore.h"
 #include "bmap.h"
 #include "glock.h"
 #include "log.h"
 #include "lops.h"
 #include "meta_io.h"
+#include "util.h"
+#include "dir.h"
 
 #define PULL 1
 
-static void do_lock_wait(struct gfs2_sbd *sdp, wait_queue_head_t *wq,
-			 atomic_t *a)
-{
-	wait_event(*wq, atomic_read(a) ? 0 : 1);
-}
-
-static void lock_for_trans(struct gfs2_sbd *sdp)
-{
-	do_lock_wait(sdp, &sdp->sd_log_trans_wq, &sdp->sd_log_flush_count);
-	atomic_inc(&sdp->sd_log_trans_count);
-}
-
-static void unlock_from_trans(struct gfs2_sbd *sdp)
-{
-	gfs2_assert_warn(sdp, atomic_read(&sdp->sd_log_trans_count));
-	if (atomic_dec_and_test(&sdp->sd_log_trans_count))
-		wake_up(&sdp->sd_log_flush_wq);
-}
-
-static void gfs2_lock_for_flush(struct gfs2_sbd *sdp)
-{
-	atomic_inc(&sdp->sd_log_flush_count);
-	do_lock_wait(sdp, &sdp->sd_log_flush_wq, &sdp->sd_log_trans_count);
-}
-
-static void gfs2_unlock_from_flush(struct gfs2_sbd *sdp)
-{
-	gfs2_assert_warn(sdp, atomic_read(&sdp->sd_log_flush_count));
-	if (atomic_dec_and_test(&sdp->sd_log_flush_count))
-		wake_up(&sdp->sd_log_trans_wq);
-}
-
 /**
  * gfs2_struct2blk - compute stuff
  * @sdp: the filesystem
@@ -77,21 +53,130 @@ unsigned int gfs2_struct2blk(struct gfs2_sbd *sdp, unsigned int nstruct,
 	first = (sdp->sd_sb.sb_bsize - sizeof(struct gfs2_log_descriptor)) / ssize;
 
 	if (nstruct > first) {
-		second = (sdp->sd_sb.sb_bsize - sizeof(struct gfs2_meta_header)) / ssize;
-		blks += DIV_RU(nstruct - first, second);
+		second = (sdp->sd_sb.sb_bsize -
+			  sizeof(struct gfs2_meta_header)) / ssize;
+		blks += DIV_ROUND_UP(nstruct - first, second);
 	}
 
 	return blks;
 }
 
-void gfs2_ail1_start(struct gfs2_sbd *sdp, int flags)
+/**
+ * gfs2_remove_from_ail - Remove an entry from the ail lists, updating counters
+ * @mapping: The associated mapping (maybe NULL)
+ * @bd: The gfs2_bufdata to remove
+ *
+ * The log lock _must_ be held when calling this function
+ *
+ */
+
+void gfs2_remove_from_ail(struct gfs2_bufdata *bd)
+{
+	bd->bd_ail = NULL;
+	list_del_init(&bd->bd_ail_st_list);
+	list_del_init(&bd->bd_ail_gl_list);
+	atomic_dec(&bd->bd_gl->gl_ail_count);
+	brelse(bd->bd_bh);
+}
+
+/**
+ * gfs2_ail1_start_one - Start I/O on a part of the AIL
+ * @sdp: the filesystem
+ * @tr: the part of the AIL
+ *
+ */
+
+static void gfs2_ail1_start_one(struct gfs2_sbd *sdp, struct gfs2_ail *ai)
+__releases(&sdp->sd_log_lock)
+__acquires(&sdp->sd_log_lock)
+{
+	struct gfs2_bufdata *bd, *s;
+	struct buffer_head *bh;
+	int retry;
+
+	do {
+		retry = 0;
+
+		list_for_each_entry_safe_reverse(bd, s, &ai->ai_ail1_list,
+						 bd_ail_st_list) {
+			bh = bd->bd_bh;
+
+			gfs2_assert(sdp, bd->bd_ail == ai);
+
+			if (!buffer_busy(bh)) {
+				if (!buffer_uptodate(bh))
+					gfs2_io_error_bh(sdp, bh);
+				list_move(&bd->bd_ail_st_list, &ai->ai_ail2_list);
+				continue;
+			}
+
+			if (!buffer_dirty(bh))
+				continue;
+
+			list_move(&bd->bd_ail_st_list, &ai->ai_ail1_list);
+
+			get_bh(bh);
+			gfs2_log_unlock(sdp);
+			lock_buffer(bh);
+			if (test_clear_buffer_dirty(bh)) {
+				bh->b_end_io = end_buffer_write_sync;
+				submit_bh(WRITE, bh);
+			} else {
+				unlock_buffer(bh);
+				brelse(bh);
+			}
+			gfs2_log_lock(sdp);
+
+			retry = 1;
+			break;
+		}
+	} while (retry);
+}
+
+/**
+ * gfs2_ail1_empty_one - Check whether or not a trans in the AIL has been synced
+ * @sdp: the filesystem
+ * @ai: the AIL entry
+ *
+ */
+
+static int gfs2_ail1_empty_one(struct gfs2_sbd *sdp, struct gfs2_ail *ai, int flags)
+{
+	struct gfs2_bufdata *bd, *s;
+	struct buffer_head *bh;
+
+	list_for_each_entry_safe_reverse(bd, s, &ai->ai_ail1_list,
+					 bd_ail_st_list) {
+		bh = bd->bd_bh;
+
+		gfs2_assert(sdp, bd->bd_ail == ai);
+
+		if (buffer_busy(bh)) {
+			if (flags & DIO_ALL)
+				continue;
+			else
+				break;
+		}
+
+		if (!buffer_uptodate(bh))
+			gfs2_io_error_bh(sdp, bh);
+
+		list_move(&bd->bd_ail_st_list, &ai->ai_ail2_list);
+	}
+
+	return list_empty(&ai->ai_ail1_list);
+}
+
+static void gfs2_ail1_start(struct gfs2_sbd *sdp, int flags)
 {
-	struct list_head *head = &sdp->sd_ail1_list;
-	uint64_t sync_gen;
-	struct list_head *first, *tmp;
-	struct gfs2_ail *first_ai, *ai;
+	struct list_head *head;
+	u64 sync_gen;
+	struct list_head *first;
+	struct gfs2_ail *first_ai, *ai, *tmp;
+	int done = 0;
 
 	gfs2_log_lock(sdp);
+	head = &sdp->sd_ail1_list;
 	if (list_empty(head)) {
 		gfs2_log_unlock(sdp);
 		return;
@@ -101,34 +186,31 @@ void gfs2_ail1_start(struct gfs2_sbd *sdp, int flags)
 	first = head->prev;
 	first_ai = list_entry(first, struct gfs2_ail, ai_list);
 	first_ai->ai_sync_gen = sync_gen;
-	gfs2_ail1_start_one(sdp, first_ai);
+	gfs2_ail1_start_one(sdp, first_ai); /* This may drop log lock */
 
 	if (flags & DIO_ALL)
 		first = NULL;
 
-	for (;;) {
-		if (first &&
-		    (head->prev != first ||
-		     gfs2_ail1_empty_one(sdp, first_ai, 0)))
+	while(!done) {
+		if (first && (head->prev != first ||
+			      gfs2_ail1_empty_one(sdp, first_ai, 0)))
 			break;
 
-		for (tmp = head->prev; tmp != head; tmp = tmp->prev) {
-			ai = list_entry(tmp, struct gfs2_ail, ai_list);
+		done = 1;
+		list_for_each_entry_safe_reverse(ai, tmp, head, ai_list) {
 			if (ai->ai_sync_gen >= sync_gen)
 				continue;
 			ai->ai_sync_gen = sync_gen;
-			gfs2_ail1_start_one(sdp, ai);
+			gfs2_ail1_start_one(sdp, ai); /* This may drop log lock */
+			done = 0;
 			break;
 		}
-
-		if (tmp == head)
-			break;
 	}
 
 	gfs2_log_unlock(sdp);
 }
 
-int gfs2_ail1_empty(struct gfs2_sbd *sdp, int flags)
+static int gfs2_ail1_empty(struct gfs2_sbd *sdp, int flags)
 {
 	struct gfs2_ail *ai, *s;
 	int ret;
@@ -149,6 +231,27 @@ int gfs2_ail1_empty(struct gfs2_sbd *sdp, int flags)
 	return ret;
 }
 
+
+/**
+ * gfs2_ail2_empty_one - Check whether or not a trans in the AIL has been synced
+ * @sdp: the filesystem
+ * @ai: the AIL entry
+ *
+ */
+
+static void gfs2_ail2_empty_one(struct gfs2_sbd *sdp, struct gfs2_ail *ai)
+{
+	struct list_head *head = &ai->ai_ail2_list;
+	struct gfs2_bufdata *bd;
+
+	while (!list_empty(head)) {
+		bd = list_entry(head->prev, struct gfs2_bufdata,
+				bd_ail_st_list);
+		gfs2_assert(sdp, bd->bd_ail == ai);
+		gfs2_remove_from_ail(bd);
+	}
+}
+
 static void ail2_empty(struct gfs2_sbd *sdp, unsigned int new_tail)
 {
 	struct gfs2_ail *ai, *safe;
@@ -180,53 +283,40 @@ static void ail2_empty(struct gfs2_sbd *sdp, unsigned int new_tail)
  * @sdp: The GFS2 superblock
  * @blks: The number of blocks to reserve
  *
+ * Note that we never give out the last few blocks of the journal. Thats
+ * due to the fact that there is a small number of header blocks
+ * associated with each log flush. The exact number can't be known until
+ * flush time, so we ensure that we have just enough free blocks at all
+ * times to avoid running out during a log flush.
+ *
  * Returns: errno
  */
 
 int gfs2_log_reserve(struct gfs2_sbd *sdp, unsigned int blks)
 {
-	LIST_HEAD(list);
 	unsigned int try = 0;
+	unsigned reserved_blks = 6 * (4096 / sdp->sd_vfs->s_blocksize);
 
 	if (gfs2_assert_warn(sdp, blks) ||
 	    gfs2_assert_warn(sdp, blks <= sdp->sd_jdesc->jd_blocks))
 		return -EINVAL;
 
-	for (;;) {
-		gfs2_log_lock(sdp);
-		if (list_empty(&list)) {
-			list_add_tail(&list, &sdp->sd_log_blks_list);
-			while (sdp->sd_log_blks_list.next != &list) {
-				DECLARE_WAITQUEUE(__wait_chan, current);
-				set_current_state(TASK_UNINTERRUPTIBLE);
-				add_wait_queue(&sdp->sd_log_blks_wait,
-					       &__wait_chan);
-				gfs2_log_unlock(sdp);
-				schedule();
-				gfs2_log_lock(sdp);
-				remove_wait_queue(&sdp->sd_log_blks_wait,
-						  &__wait_chan);
-				set_current_state(TASK_RUNNING);
-			}
-		}
-		/* Never give away the last block so we can
-		   always pull the tail if we need to. */
-		if (sdp->sd_log_blks_free > blks) {
-			sdp->sd_log_blks_free -= blks;
-			list_del(&list);
-			gfs2_log_unlock(sdp);
-			wake_up(&sdp->sd_log_blks_wait);
-			break;
-		}
-
+	mutex_lock(&sdp->sd_log_reserve_mutex);
+	gfs2_log_lock(sdp);
+	while(atomic_read(&sdp->sd_log_blks_free) <= (blks + reserved_blks)) {
 		gfs2_log_unlock(sdp);
 		gfs2_ail1_empty(sdp, 0);
-		gfs2_log_flush(sdp);
+		gfs2_log_flush(sdp, NULL);
 
 		if (try++)
 			gfs2_ail1_start(sdp, 0);
+		gfs2_log_lock(sdp);
 	}
-	lock_for_trans(sdp);
+	atomic_sub(blks, &sdp->sd_log_blks_free);
+	gfs2_log_unlock(sdp);
+	mutex_unlock(&sdp->sd_log_reserve_mutex);
+
+	down_read(&sdp->sd_log_flush_lock);
 
 	return 0;
 }
@@ -240,25 +330,25 @@ int gfs2_log_reserve(struct gfs2_sbd *sdp, unsigned int blks)
 
 void gfs2_log_release(struct gfs2_sbd *sdp, unsigned int blks)
 {
-	unlock_from_trans(sdp);
 
 	gfs2_log_lock(sdp);
-	sdp->sd_log_blks_free += blks;
+	atomic_add(blks, &sdp->sd_log_blks_free);
 	gfs2_assert_withdraw(sdp,
-			     sdp->sd_log_blks_free <= sdp->sd_jdesc->jd_blocks);
+			     atomic_read(&sdp->sd_log_blks_free) <= sdp->sd_jdesc->jd_blocks);
 	gfs2_log_unlock(sdp);
+	up_read(&sdp->sd_log_flush_lock);
 }
 
-static uint64_t log_bmap(struct gfs2_sbd *sdp, unsigned int lbn)
+static u64 log_bmap(struct gfs2_sbd *sdp, unsigned int lbn)
 {
-	int new = 0;
-	uint64_t dbn;
-	int error;
+	struct gfs2_journal_extent *je;
 
-	error = gfs2_block_map(get_v2ip(sdp->sd_jdesc->jd_inode), lbn, &new, &dbn, NULL);
-	gfs2_assert_withdraw(sdp, !error && dbn);
+	list_for_each_entry(je, &sdp->sd_jdesc->extent_list, extent_list) {
+		if (lbn >= je->lblock && lbn < je->lblock + je->blocks)
+			return je->dblock + lbn - je->lblock;
+	}
 
-	return dbn;
+	return -1;
 }
 
 /**
@@ -273,8 +363,7 @@ static uint64_t log_bmap(struct gfs2_sbd *sdp, unsigned int lbn)
  * Returns: the distance in blocks
  */
 
-static inline unsigned int log_distance(struct gfs2_sbd *sdp,
-					unsigned int newer,
+static inline unsigned int log_distance(struct gfs2_sbd *sdp, unsigned int newer,
 					unsigned int older)
 {
 	int dist;
@@ -286,6 +375,58 @@ static inline unsigned int log_distance(struct gfs2_sbd *sdp,
 	return dist;
 }
 
+/**
+ * calc_reserved - Calculate the number of blocks to reserve when
+ *                 refunding a transaction's unused buffers.
+ * @sdp: The GFS2 superblock
+ *
+ * This is complex.  We need to reserve room for all our currently used
+ * metadata buffers (e.g. normal file I/O rewriting file time stamps) and 
+ * all our journaled data buffers for journaled files (e.g. files in the 
+ * meta_fs like rindex, or files for which chattr +j was done.)
+ * If we don't reserve enough space, gfs2_log_refund and gfs2_log_flush
+ * will count it as free space (sd_log_blks_free) and corruption will follow.
+ *
+ * We can have metadata bufs and jdata bufs in the same journal.  So each
+ * type gets its own log header, for which we need to reserve a block.
+ * In fact, each type has the potential for needing more than one header 
+ * in cases where we have more buffers than will fit on a journal page.
+ * Metadata journal entries take up half the space of journaled buffer entries.
+ * Thus, metadata entries have buf_limit (502) and journaled buffers have
+ * databuf_limit (251) before they cause a wrap around.
+ *
+ * Also, we need to reserve blocks for revoke journal entries and one for an
+ * overall header for the lot.
+ *
+ * Returns: the number of blocks reserved
+ */
+static unsigned int calc_reserved(struct gfs2_sbd *sdp)
+{
+	unsigned int reserved = 0;
+	unsigned int mbuf_limit, metabufhdrs_needed;
+	unsigned int dbuf_limit, databufhdrs_needed;
+	unsigned int revokes = 0;
+
+	mbuf_limit = buf_limit(sdp);
+	metabufhdrs_needed = (sdp->sd_log_commited_buf +
+			      (mbuf_limit - 1)) / mbuf_limit;
+	dbuf_limit = databuf_limit(sdp);
+	databufhdrs_needed = (sdp->sd_log_commited_databuf +
+			      (dbuf_limit - 1)) / dbuf_limit;
+
+	if (sdp->sd_log_commited_revoke)
+		revokes = gfs2_struct2blk(sdp, sdp->sd_log_commited_revoke,
+					  sizeof(u64));
+
+	reserved = sdp->sd_log_commited_buf + metabufhdrs_needed +
+		sdp->sd_log_commited_databuf + databufhdrs_needed +
+		revokes;
+	/* One for the overall header */
+	if (reserved)
+		reserved++;
+	return reserved;
+}
+
 static unsigned int current_tail(struct gfs2_sbd *sdp)
 {
 	struct gfs2_ail *ai;
@@ -293,11 +434,10 @@ static unsigned int current_tail(struct gfs2_sbd *sdp)
 
 	gfs2_log_lock(sdp);
 
-	if (list_empty(&sdp->sd_ail1_list))
+	if (list_empty(&sdp->sd_ail1_list)) {
 		tail = sdp->sd_log_head;
-	else {
-		ai = list_entry(sdp->sd_ail1_list.prev,
-				struct gfs2_ail, ai_list);
+	} else {
+		ai = list_entry(sdp->sd_ail1_list.prev, struct gfs2_ail, ai_list);
 		tail = ai->ai_first;
 	}
 
@@ -306,11 +446,10 @@ static unsigned int current_tail(struct gfs2_sbd *sdp)
 	return tail;
 }
 
-static inline void log_incr_head(struct gfs2_sbd *sdp)
+void gfs2_log_incr_head(struct gfs2_sbd *sdp)
 {
 	if (sdp->sd_log_flush_head == sdp->sd_log_tail)
-		gfs2_assert_withdraw(sdp,
-				sdp->sd_log_flush_head == sdp->sd_log_head);
+		BUG_ON(sdp->sd_log_flush_head != sdp->sd_log_head);
 
 	if (++sdp->sd_log_flush_head == sdp->sd_jdesc->jd_blocks) {
 		sdp->sd_log_flush_head = 0;
@@ -319,6 +458,23 @@ static inline void log_incr_head(struct gfs2_sbd *sdp)
 }
 
 /**
+ * gfs2_log_write_endio - End of I/O for a log buffer
+ * @bh: The buffer head
+ * @uptodate: I/O Status
+ *
+ */
+
+static void gfs2_log_write_endio(struct buffer_head *bh, int uptodate)
+{
+	struct gfs2_sbd *sdp = bh->b_private;
+	bh->b_private = NULL;
+
+	end_buffer_write_sync(bh, uptodate);
+	if (atomic_dec_and_test(&sdp->sd_log_in_flight))
+		wake_up(&sdp->sd_log_flush_wait);
+}
+
+/**
  * gfs2_log_get_buf - Get and initialize a buffer to use for log control data
  * @sdp: The GFS2 superblock
  *
@@ -327,26 +483,44 @@ static inline void log_incr_head(struct gfs2_sbd *sdp)
 
 struct buffer_head *gfs2_log_get_buf(struct gfs2_sbd *sdp)
 {
-	uint64_t blkno = log_bmap(sdp, sdp->sd_log_flush_head);
-	struct gfs2_log_buf *lb;
+	u64 blkno = log_bmap(sdp, sdp->sd_log_flush_head);
 	struct buffer_head *bh;
 
-	lb = kzalloc(sizeof(struct gfs2_log_buf), GFP_NOFS | __GFP_NOFAIL);
-	list_add(&lb->lb_list, &sdp->sd_log_flush_list);
-
-	bh = lb->lb_bh = sb_getblk(sdp->sd_vfs, blkno);
+	bh = sb_getblk(sdp->sd_vfs, blkno);
 	lock_buffer(bh);
 	memset(bh->b_data, 0, bh->b_size);
 	set_buffer_uptodate(bh);
 	clear_buffer_dirty(bh);
-	unlock_buffer(bh);
-
-	log_incr_head(sdp);
+	gfs2_log_incr_head(sdp);
+	atomic_inc(&sdp->sd_log_in_flight);
+	bh->b_private = sdp;
+	bh->b_end_io = gfs2_log_write_endio;
 
 	return bh;
 }
 
 /**
+ * gfs2_fake_write_endio - 
+ * @bh: The buffer head
+ * @uptodate: The I/O Status
+ *
+ */
+
+static void gfs2_fake_write_endio(struct buffer_head *bh, int uptodate)
+{
+	struct buffer_head *real_bh = bh->b_private;
+	struct gfs2_bufdata *bd = real_bh->b_private;
+	struct gfs2_sbd *sdp = bd->bd_gl->gl_sbd;
+
+	end_buffer_write_sync(bh, uptodate);
+	free_buffer_head(bh);
+	unlock_buffer(real_bh);
+	brelse(real_bh);
+	if (atomic_dec_and_test(&sdp->sd_log_in_flight))
+		wake_up(&sdp->sd_log_flush_wait);
+}
+
+/**
  * gfs2_log_fake_buf - Build a fake buffer head to write metadata buffer to log
  * @sdp: the filesystem
  * @data: the data the buffer_head should point to
@@ -357,37 +531,34 @@ struct buffer_head *gfs2_log_get_buf(struct gfs2_sbd *sdp)
 struct buffer_head *gfs2_log_fake_buf(struct gfs2_sbd *sdp,
 				      struct buffer_head *real)
 {
-	uint64_t blkno = log_bmap(sdp, sdp->sd_log_flush_head);
-	struct gfs2_log_buf *lb;
+	u64 blkno = log_bmap(sdp, sdp->sd_log_flush_head);
 	struct buffer_head *bh;
 
-	lb = kzalloc(sizeof(struct gfs2_log_buf), GFP_NOFS | __GFP_NOFAIL);
-	list_add(&lb->lb_list, &sdp->sd_log_flush_list);
-	lb->lb_real = real;
-
-	bh = lb->lb_bh = alloc_buffer_head(GFP_NOFS | __GFP_NOFAIL);
+	bh = alloc_buffer_head(GFP_NOFS | __GFP_NOFAIL);
 	atomic_set(&bh->b_count, 1);
-	bh->b_state = (1 << BH_Mapped) | (1 << BH_Uptodate);
+	bh->b_state = (1 << BH_Mapped) | (1 << BH_Uptodate) | (1 << BH_Lock);
 	set_bh_page(bh, real->b_page, bh_offset(real));
 	bh->b_blocknr = blkno;
 	bh->b_size = sdp->sd_sb.sb_bsize;
 	bh->b_bdev = sdp->sd_vfs->s_bdev;
+	bh->b_private = real;
+	bh->b_end_io = gfs2_fake_write_endio;
 
-	log_incr_head(sdp);
+	gfs2_log_incr_head(sdp);
+	atomic_inc(&sdp->sd_log_in_flight);
 
 	return bh;
 }
 
-static void log_pull_tail(struct gfs2_sbd *sdp, unsigned int new_tail, int pull)
+static void log_pull_tail(struct gfs2_sbd *sdp, unsigned int new_tail)
 {
 	unsigned int dist = log_distance(sdp, new_tail, sdp->sd_log_tail);
 
 	ail2_empty(sdp, new_tail);
 
 	gfs2_log_lock(sdp);
-	sdp->sd_log_blks_free += dist - ((pull) ? 1 : 0);
-	gfs2_assert_withdraw(sdp,
-			     sdp->sd_log_blks_free <= sdp->sd_jdesc->jd_blocks);
+	atomic_add(dist, &sdp->sd_log_blks_free);
+	gfs2_assert_withdraw(sdp, atomic_read(&sdp->sd_log_blks_free) <= sdp->sd_jdesc->jd_blocks);
 	gfs2_log_unlock(sdp);
 
 	sdp->sd_log_tail = new_tail;
@@ -400,22 +571,19 @@ static void log_pull_tail(struct gfs2_sbd *sdp, unsigned int new_tail, int pull)
  * Returns: the initialized log buffer descriptor
  */
 
-static void log_write_header(struct gfs2_sbd *sdp, uint32_t flags, int pull)
+static void log_write_header(struct gfs2_sbd *sdp, u32 flags, int pull)
 {
-	uint64_t blkno = log_bmap(sdp, sdp->sd_log_flush_head);
+	u64 blkno = log_bmap(sdp, sdp->sd_log_flush_head);
 	struct buffer_head *bh;
 	struct gfs2_log_header *lh;
 	unsigned int tail;
-	uint32_t hash;
-
-	atomic_inc(&sdp->sd_log_flush_ondisk);
+	u32 hash;
 
 	bh = sb_getblk(sdp->sd_vfs, blkno);
 	lock_buffer(bh);
 	memset(bh->b_data, 0, bh->b_size);
 	set_buffer_uptodate(bh);
 	clear_buffer_dirty(bh);
-	unlock_buffer(bh);
 
 	gfs2_ail1_empty(sdp, 0);
 	tail = current_tail(sdp);
@@ -423,93 +591,145 @@ static void log_write_header(struct gfs2_sbd *sdp, uint32_t flags, int pull)
 	lh = (struct gfs2_log_header *)bh->b_data;
 	memset(lh, 0, sizeof(struct gfs2_log_header));
 	lh->lh_header.mh_magic = cpu_to_be32(GFS2_MAGIC);
-	lh->lh_header.mh_type = cpu_to_be16(GFS2_METATYPE_LH);
-	lh->lh_header.mh_format = cpu_to_be16(GFS2_FORMAT_LH);
-	lh->lh_sequence = be64_to_cpu(sdp->sd_log_sequence++);
-	lh->lh_flags = be32_to_cpu(flags);
-	lh->lh_tail = be32_to_cpu(tail);
-	lh->lh_blkno = be32_to_cpu(sdp->sd_log_flush_head);
+	lh->lh_header.mh_type = cpu_to_be32(GFS2_METATYPE_LH);
+	lh->lh_header.mh_format = cpu_to_be32(GFS2_FORMAT_LH);
+	lh->lh_sequence = cpu_to_be64(sdp->sd_log_sequence++);
+	lh->lh_flags = cpu_to_be32(flags);
+	lh->lh_tail = cpu_to_be32(tail);
+	lh->lh_blkno = cpu_to_be32(sdp->sd_log_flush_head);
 	hash = gfs2_disk_hash(bh->b_data, sizeof(struct gfs2_log_header));
 	lh->lh_hash = cpu_to_be32(hash);
 
-	set_buffer_dirty(bh);
-	if (sync_dirty_buffer(bh))
+	bh->b_end_io = end_buffer_write_sync;
+	if (test_bit(SDF_NOBARRIERS, &sdp->sd_flags))
+		goto skip_barrier;
+	get_bh(bh);
+	submit_bh(WRITE_BARRIER | (1 << BIO_RW_META), bh);
+	wait_on_buffer(bh);
+	if (buffer_eopnotsupp(bh)) {
+		clear_buffer_eopnotsupp(bh);
+		set_buffer_uptodate(bh);
+		set_bit(SDF_NOBARRIERS, &sdp->sd_flags);
+		lock_buffer(bh);
+skip_barrier:
+		get_bh(bh);
+		submit_bh(WRITE_SYNC | (1 << BIO_RW_META), bh);
+		wait_on_buffer(bh);
+	}
+	if (!buffer_uptodate(bh))
 		gfs2_io_error_bh(sdp, bh);
 	brelse(bh);
 
 	if (sdp->sd_log_tail != tail)
-		log_pull_tail(sdp, tail, pull);
+		log_pull_tail(sdp, tail);
 	else
 		gfs2_assert_withdraw(sdp, !pull);
 
 	sdp->sd_log_idle = (tail == sdp->sd_log_flush_head);
-	log_incr_head(sdp);
+	gfs2_log_incr_head(sdp);
 }
 
 static void log_flush_commit(struct gfs2_sbd *sdp)
 {
-	struct list_head *head = &sdp->sd_log_flush_list;
-	struct gfs2_log_buf *lb;
-	struct buffer_head *bh;
-	unsigned int d;
-
-	d = log_distance(sdp, sdp->sd_log_flush_head, sdp->sd_log_head);
+	DEFINE_WAIT(wait);
+
+	if (atomic_read(&sdp->sd_log_in_flight)) {
+		do {
+			prepare_to_wait(&sdp->sd_log_flush_wait, &wait,
+					TASK_UNINTERRUPTIBLE);
+			if (atomic_read(&sdp->sd_log_in_flight))
+				io_schedule();
+		} while(atomic_read(&sdp->sd_log_in_flight));
+		finish_wait(&sdp->sd_log_flush_wait, &wait);
+	}
 
-	gfs2_assert_withdraw(sdp, d + 1 == sdp->sd_log_blks_reserved);
+	log_write_header(sdp, 0, 0);
+}
 
-	while (!list_empty(head)) {
-		lb = list_entry(head->next, struct gfs2_log_buf, lb_list);
-		list_del(&lb->lb_list);
-		bh = lb->lb_bh;
+static void gfs2_ordered_write(struct gfs2_sbd *sdp)
+{
+	struct gfs2_bufdata *bd;
+	struct buffer_head *bh;
+	LIST_HEAD(written);
 
-		wait_on_buffer(bh);
-		if (!buffer_uptodate(bh))
-			gfs2_io_error_bh(sdp, bh);
-		if (lb->lb_real) {
-			while (atomic_read(&bh->b_count) != 1)  /* Grrrr... */
-				schedule();
-			free_buffer_head(bh);
-		} else
+	gfs2_log_lock(sdp);
+	while (!list_empty(&sdp->sd_log_le_ordered)) {
+		bd = list_entry(sdp->sd_log_le_ordered.next, struct gfs2_bufdata, bd_le.le_list);
+		list_move(&bd->bd_le.le_list, &written);
+		bh = bd->bd_bh;
+		if (!buffer_dirty(bh))
+			continue;
+		get_bh(bh);
+		gfs2_log_unlock(sdp);
+		lock_buffer(bh);
+		if (buffer_mapped(bh) && test_clear_buffer_dirty(bh)) {
+			bh->b_end_io = end_buffer_write_sync;
+			submit_bh(WRITE, bh);
+		} else {
+			unlock_buffer(bh);
 			brelse(bh);
-		kfree(lb);
+		}
+		gfs2_log_lock(sdp);
 	}
+	list_splice(&written, &sdp->sd_log_le_ordered);
+	gfs2_log_unlock(sdp);
+}
 
-	log_write_header(sdp, 0, 0);
+static void gfs2_ordered_wait(struct gfs2_sbd *sdp)
+{
+	struct gfs2_bufdata *bd;
+	struct buffer_head *bh;
+
+	gfs2_log_lock(sdp);
+	while (!list_empty(&sdp->sd_log_le_ordered)) {
+		bd = list_entry(sdp->sd_log_le_ordered.prev, struct gfs2_bufdata, bd_le.le_list);
+		bh = bd->bd_bh;
+		if (buffer_locked(bh)) {
+			get_bh(bh);
+			gfs2_log_unlock(sdp);
+			wait_on_buffer(bh);
+			brelse(bh);
+			gfs2_log_lock(sdp);
+			continue;
+		}
+		list_del_init(&bd->bd_le.le_list);
+	}
+	gfs2_log_unlock(sdp);
 }
 
 /**
- * gfs2_log_flush_i - flush incore transaction(s)
+ * gfs2_log_flush - flush incore transaction(s)
  * @sdp: the filesystem
  * @gl: The glock structure to flush.  If NULL, flush the whole incore log
  *
  */
 
-void gfs2_log_flush_i(struct gfs2_sbd *sdp, struct gfs2_glock *gl)
+void __gfs2_log_flush(struct gfs2_sbd *sdp, struct gfs2_glock *gl)
 {
 	struct gfs2_ail *ai;
 
-	atomic_inc(&sdp->sd_log_flush_incore);
+	down_write(&sdp->sd_log_flush_lock);
+
+	/* Log might have been flushed while we waited for the flush lock */
+	if (gl && !test_bit(GLF_LFLUSH, &gl->gl_flags)) {
+		up_write(&sdp->sd_log_flush_lock);
+		return;
+	}
 
 	ai = kzalloc(sizeof(struct gfs2_ail), GFP_NOFS | __GFP_NOFAIL);
 	INIT_LIST_HEAD(&ai->ai_ail1_list);
 	INIT_LIST_HEAD(&ai->ai_ail2_list);
-	gfs2_lock_for_flush(sdp);
 
-	if (gl) {
-		gfs2_log_lock(sdp);
-		if (list_empty(&gl->gl_le.le_list)) {
-			gfs2_log_unlock(sdp);
-			gfs2_unlock_from_flush(sdp);
-			kfree(ai);
-			return;
-		}
-		gfs2_log_unlock(sdp);
+	if (sdp->sd_log_num_buf != sdp->sd_log_commited_buf) {
+		printk(KERN_INFO "GFS2: log buf %u %u\n", sdp->sd_log_num_buf,
+		       sdp->sd_log_commited_buf);
+		gfs2_assert_withdraw(sdp, 0);
+	}
+	if (sdp->sd_log_num_databuf != sdp->sd_log_commited_databuf) {
+		printk(KERN_INFO "GFS2: log databuf %u %u\n",
+		       sdp->sd_log_num_databuf, sdp->sd_log_commited_databuf);
+		gfs2_assert_withdraw(sdp, 0);
 	}
-
-	mutex_lock(&sdp->sd_log_flush_lock);
-
-	gfs2_assert_withdraw(sdp,
-			sdp->sd_log_num_buf == sdp->sd_log_commited_buf);
 	gfs2_assert_withdraw(sdp,
 			sdp->sd_log_num_revoke == sdp->sd_log_commited_revoke);
 
@@ -517,64 +737,77 @@ void gfs2_log_flush_i(struct gfs2_sbd *sdp, struct gfs2_glock *gl)
 	sdp->sd_log_flush_wrapped = 0;
 	ai->ai_first = sdp->sd_log_flush_head;
 
+	gfs2_ordered_write(sdp);
 	lops_before_commit(sdp);
-	if (!list_empty(&sdp->sd_log_flush_list))
+	gfs2_ordered_wait(sdp);
+
+	if (sdp->sd_log_head != sdp->sd_log_flush_head)
 		log_flush_commit(sdp);
-	else if (sdp->sd_log_tail != current_tail(sdp) && !sdp->sd_log_idle)
+	else if (sdp->sd_log_tail != current_tail(sdp) && !sdp->sd_log_idle){
+		gfs2_log_lock(sdp);
+		atomic_dec(&sdp->sd_log_blks_free); /* Adjust for unreserved buffer */
+		gfs2_log_unlock(sdp);
 		log_write_header(sdp, 0, PULL);
+	}
 	lops_after_commit(sdp, ai);
-	sdp->sd_log_head = sdp->sd_log_flush_head;
-	if (sdp->sd_log_flush_wrapped)
-		sdp->sd_log_wraps++;
-
-	sdp->sd_log_blks_reserved =
-		sdp->sd_log_commited_buf =
-		sdp->sd_log_commited_revoke = 0;
 
 	gfs2_log_lock(sdp);
+	sdp->sd_log_head = sdp->sd_log_flush_head;
+	sdp->sd_log_blks_reserved = 0;
+	sdp->sd_log_commited_buf = 0;
+	sdp->sd_log_commited_databuf = 0;
+	sdp->sd_log_commited_revoke = 0;
+
 	if (!list_empty(&ai->ai_ail1_list)) {
 		list_add(&ai->ai_list, &sdp->sd_ail1_list);
 		ai = NULL;
 	}
 	gfs2_log_unlock(sdp);
 
-	mutex_unlock(&sdp->sd_log_flush_lock);
 	sdp->sd_vfs->s_dirt = 0;
-	gfs2_unlock_from_flush(sdp);
+	up_write(&sdp->sd_log_flush_lock);
 
 	kfree(ai);
 }
 
 static void log_refund(struct gfs2_sbd *sdp, struct gfs2_trans *tr)
 {
-	unsigned int reserved = 1;
-	unsigned int old;
+	unsigned int reserved;
+	unsigned int unused;
 
 	gfs2_log_lock(sdp);
 
 	sdp->sd_log_commited_buf += tr->tr_num_buf_new - tr->tr_num_buf_rm;
-	gfs2_assert_withdraw(sdp, ((int)sdp->sd_log_commited_buf) >= 0);
+	sdp->sd_log_commited_databuf += tr->tr_num_databuf_new -
+		tr->tr_num_databuf_rm;
+	gfs2_assert_withdraw(sdp, (((int)sdp->sd_log_commited_buf) >= 0) ||
+			     (((int)sdp->sd_log_commited_databuf) >= 0));
 	sdp->sd_log_commited_revoke += tr->tr_num_revoke - tr->tr_num_revoke_rm;
 	gfs2_assert_withdraw(sdp, ((int)sdp->sd_log_commited_revoke) >= 0);
+	reserved = calc_reserved(sdp);
+	gfs2_assert_withdraw(sdp, sdp->sd_log_blks_reserved + tr->tr_reserved >= reserved);
+	unused = sdp->sd_log_blks_reserved - reserved + tr->tr_reserved;
+	atomic_add(unused, &sdp->sd_log_blks_free);
+	gfs2_assert_withdraw(sdp, atomic_read(&sdp->sd_log_blks_free) <=
+			     sdp->sd_jdesc->jd_blocks);
+	sdp->sd_log_blks_reserved = reserved;
 
-	if (sdp->sd_log_commited_buf)
-		reserved += 1 + sdp->sd_log_commited_buf + sdp->sd_log_commited_buf/503;
-	if (sdp->sd_log_commited_revoke)
-		reserved += gfs2_struct2blk(sdp, sdp->sd_log_commited_revoke,
-					    sizeof(uint64_t));
-
-	old = sdp->sd_log_blks_free;
-	sdp->sd_log_blks_free += tr->tr_reserved -
-				 (reserved - sdp->sd_log_blks_reserved);
-
-	gfs2_assert_withdraw(sdp,
-			     sdp->sd_log_blks_free >= old);
-	gfs2_assert_withdraw(sdp,
-			     sdp->sd_log_blks_free <= sdp->sd_jdesc->jd_blocks);
+	gfs2_log_unlock(sdp);
+}
 
-	sdp->sd_log_blks_reserved = reserved;
+static void buf_lo_incore_commit(struct gfs2_sbd *sdp, struct gfs2_trans *tr)
+{
+	struct list_head *head = &tr->tr_list_buf;
+	struct gfs2_bufdata *bd;
 
+	gfs2_log_lock(sdp);
+	while (!list_empty(head)) {
+		bd = list_entry(head->next, struct gfs2_bufdata, bd_list_tr);
+		list_del_init(&bd->bd_list_tr);
+		tr->tr_num_buf--;
+	}
 	gfs2_log_unlock(sdp);
+	gfs2_assert_warn(sdp, !tr->tr_num_buf);
 }
 
 /**
@@ -588,19 +821,15 @@ static void log_refund(struct gfs2_sbd *sdp, struct gfs2_trans *tr)
 void gfs2_log_commit(struct gfs2_sbd *sdp, struct gfs2_trans *tr)
 {
 	log_refund(sdp, tr);
-	lops_incore_commit(sdp, tr);
+	buf_lo_incore_commit(sdp, tr);
 
 	sdp->sd_vfs->s_dirt = 1;
-	unlock_from_trans(sdp);
-
-	kfree(tr);
+	up_read(&sdp->sd_log_flush_lock);
 
 	gfs2_log_lock(sdp);
-	if (sdp->sd_log_num_buf > gfs2_tune_get(sdp, gt_incore_log_blocks)) {
-		gfs2_log_unlock(sdp);
-		gfs2_log_flush(sdp);
-	} else
-		gfs2_log_unlock(sdp);
+	if (sdp->sd_log_num_buf > gfs2_tune_get(sdp, gt_incore_log_blocks))
+		wake_up_process(sdp->sd_logd_process);
+	gfs2_log_unlock(sdp);
 }
 
 /**
@@ -611,13 +840,10 @@ void gfs2_log_commit(struct gfs2_sbd *sdp, struct gfs2_trans *tr)
 
 void gfs2_log_shutdown(struct gfs2_sbd *sdp)
 {
-	mutex_lock(&sdp->sd_log_flush_lock);
+	down_write(&sdp->sd_log_flush_lock);
 
-	gfs2_assert_withdraw(sdp, !atomic_read(&sdp->sd_log_trans_count));
 	gfs2_assert_withdraw(sdp, !sdp->sd_log_blks_reserved);
-	gfs2_assert_withdraw(sdp, !sdp->sd_log_num_gl);
 	gfs2_assert_withdraw(sdp, !sdp->sd_log_num_buf);
-	gfs2_assert_withdraw(sdp, !sdp->sd_log_num_jdata);
 	gfs2_assert_withdraw(sdp, !sdp->sd_log_num_revoke);
 	gfs2_assert_withdraw(sdp, !sdp->sd_log_num_rg);
 	gfs2_assert_withdraw(sdp, !sdp->sd_log_num_databuf);
@@ -626,18 +852,73 @@ void gfs2_log_shutdown(struct gfs2_sbd *sdp)
 	sdp->sd_log_flush_head = sdp->sd_log_head;
 	sdp->sd_log_flush_wrapped = 0;
 
-	log_write_header(sdp, GFS2_LOG_HEAD_UNMOUNT, 0);
+	log_write_header(sdp, GFS2_LOG_HEAD_UNMOUNT,
+			 (sdp->sd_log_tail == current_tail(sdp)) ? 0 : PULL);
 
-	gfs2_assert_withdraw(sdp, sdp->sd_log_blks_free ==
-			     sdp->sd_jdesc->jd_blocks);
-	gfs2_assert_withdraw(sdp, sdp->sd_log_head == sdp->sd_log_tail);
-	gfs2_assert_withdraw(sdp, list_empty(&sdp->sd_ail2_list));
+	gfs2_assert_warn(sdp, atomic_read(&sdp->sd_log_blks_free) == sdp->sd_jdesc->jd_blocks);
+	gfs2_assert_warn(sdp, sdp->sd_log_head == sdp->sd_log_tail);
+	gfs2_assert_warn(sdp, list_empty(&sdp->sd_ail2_list));
 
 	sdp->sd_log_head = sdp->sd_log_flush_head;
-	if (sdp->sd_log_flush_wrapped)
-		sdp->sd_log_wraps++;
 	sdp->sd_log_tail = sdp->sd_log_head;
 
-	mutex_unlock(&sdp->sd_log_flush_lock);
+	up_write(&sdp->sd_log_flush_lock);
+}
+
+
+/**
+ * gfs2_meta_syncfs - sync all the buffers in a filesystem
+ * @sdp: the filesystem
+ *
+ */
+
+void gfs2_meta_syncfs(struct gfs2_sbd *sdp)
+{
+	gfs2_log_flush(sdp, NULL);
+	for (;;) {
+		gfs2_ail1_start(sdp, DIO_ALL);
+		if (gfs2_ail1_empty(sdp, DIO_ALL))
+			break;
+		msleep(10);
+	}
+}
+
+
+/**
+ * gfs2_logd - Update log tail as Active Items get flushed to in-place blocks
+ * @sdp: Pointer to GFS2 superblock
+ *
+ * Also, periodically check to make sure that we're using the most recent
+ * journal index.
+ */
+
+int gfs2_logd(void *data)
+{
+	struct gfs2_sbd *sdp = data;
+	unsigned long t;
+	int need_flush;
+
+	while (!kthread_should_stop()) {
+		/* Advance the log tail */
+
+		t = sdp->sd_log_flush_time +
+		    gfs2_tune_get(sdp, gt_log_flush_secs) * HZ;
+
+		gfs2_ail1_empty(sdp, DIO_ALL);
+		gfs2_log_lock(sdp);
+		need_flush = sdp->sd_log_num_buf > gfs2_tune_get(sdp, gt_incore_log_blocks);
+		gfs2_log_unlock(sdp);
+		if (need_flush || time_after_eq(jiffies, t)) {
+			gfs2_log_flush(sdp, NULL);
+			sdp->sd_log_flush_time = jiffies;
+		}
+
+		t = gfs2_tune_get(sdp, gt_logd_secs) * HZ;
+		if (freezing(current))
+			refrigerator();
+		schedule_timeout_interruptible(t);
+	}
+
+	return 0;
 }