[GFS2] Further updates to dir and logging code

This reduces the size of the directory code by about 3k and gets
readdir() to use the functions which were introduced in the previous
directory code update.

Two memory allocations are merged into one. Eliminates zeroing of some
buffers which were never used before they were initialised by
other data.

There is still scope for further improvement in the directory code.

On the logging side, a hand created mutex has been replaced by a
standard Linux mutex in the log allocation code.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

1 files changed, 6 insertions, 28 deletions

diff --git a/fs/gfs2/log.c b/fs/gfs2/log.c
index e6a84f7a9b71..16c14441a371 100644
--- a/fs/gfs2/log.c
+++ b/fs/gfs2/log.c
@@ -13,6 +13,7 @@
 #include <linux/completion.h>
 #include <linux/buffer_head.h>
 #include <linux/gfs2_ondisk.h>
+#include <linux/crc32.h>
 #include <asm/semaphore.h>
 
 #include "gfs2.h"
@@ -24,18 +25,13 @@
 #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);
+	wait_event(sdp->sd_log_trans_wq, atomic_read(&sdp->sd_log_flush_count) ? 0 : 1);
 	atomic_inc(&sdp->sd_log_trans_count);
 }
 
@@ -49,7 +45,7 @@ static void unlock_from_trans(struct gfs2_sbd *sdp)
 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);
+	wait_event(sdp->sd_log_flush_wq, atomic_read(&sdp->sd_log_trans_count) ? 0 : 1);
 }
 
 static void gfs2_unlock_from_flush(struct gfs2_sbd *sdp)
@@ -191,37 +187,19 @@ static void ail2_empty(struct gfs2_sbd *sdp, unsigned int new_tail)
 
 int gfs2_log_reserve(struct gfs2_sbd *sdp, unsigned int blks)
 {
-	LIST_HEAD(list);
 	unsigned int try = 0;
 
 	if (gfs2_assert_warn(sdp, blks) ||
 	    gfs2_assert_warn(sdp, blks <= sdp->sd_jdesc->jd_blocks))
 		return -EINVAL;
 
+	mutex_lock(&sdp->sd_log_reserve_mutex);
 	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);
+			mutex_unlock(&sdp->sd_log_reserve_mutex);
 			break;
 		}