GFS2: Merge lock_dlm module into GFS2

This is the big patch that I've been working on for some time
now. There are many reasons for wanting to make this change
such as:
 o Reducing overhead by eliminating duplicated fields between structures
 o Simplifcation of the code (reduces the code size by a fair bit)
 o The locking interface is now the DLM interface itself as proposed
   some time ago.
 o Fewer lookups of glocks when processing replies from the DLM
 o Fewer memory allocations/deallocations for each glock
 o Scope to do further optimisations in the future (but this patch is
   more than big enough for now!)

Please note that (a) this patch relates to the lock_dlm module and
not the DLM itself, that is still a separate module; and (b) that
we retain the ability to build GFS2 as a standalone single node
filesystem with out requiring the DLM.

This patch needs a lot of testing, hence my keeping it I restarted
my -git tree after the last merge window. That way, this has the maximum
exposure before its merged. This is (modulo a few minor bug fixes) the
same patch that I've been posting on and off the the last three months
and its passed a number of different tests so far.

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

1 files changed, 3 insertions, 9 deletions

diff --git a/fs/gfs2/quota.c b/fs/gfs2/quota.c
index e8ef0f80fb11..8d53f66b5bcc 100644
--- a/fs/gfs2/quota.c
+++ b/fs/gfs2/quota.c
@@ -45,7 +45,6 @@
 #include <linux/fs.h>
 #include <linux/bio.h>
 #include <linux/gfs2_ondisk.h>
-#include <linux/lm_interface.h>
 #include <linux/kthread.h>
 #include <linux/freezer.h>
 
@@ -108,7 +107,7 @@ int gfs2_shrink_qd_memory(int nr, gfp_t gfp_mask)
                 gfs2_assert_warn(sdp, !qd->qd_slot_count);
                 gfs2_assert_warn(sdp, !qd->qd_bh_count);
 
-                gfs2_lvb_unhold(qd->qd_gl);
+                gfs2_glock_put(qd->qd_gl);
                 atomic_dec(&sdp->sd_quota_count);
 
                 /* Delete it from the common reclaim list */
@@ -157,11 +156,6 @@ static int qd_alloc(struct gfs2_sbd *sdp, int user, u32 id,
         if (error)
                 goto fail;
 
-        error = gfs2_lvb_hold(qd->qd_gl);
-        gfs2_glock_put(qd->qd_gl);
-        if (error)
-                goto fail;
-
         *qdp = qd;
 
         return 0;
@@ -211,7 +205,7 @@ static int qd_get(struct gfs2_sbd *sdp, int user, u32 id, int create,
 
                 if (qd || !create) {
                         if (new_qd) {
-                                gfs2_lvb_unhold(new_qd->qd_gl);
+                                gfs2_glock_put(new_qd->qd_gl);
                                 kmem_cache_free(gfs2_quotad_cachep, new_qd);
                         }
                         *qdp = qd;
@@ -1280,7 +1274,7 @@ void gfs2_quota_cleanup(struct gfs2_sbd *sdp)
                         gfs2_assert_warn(sdp, qd->qd_slot_count == 1);
                 gfs2_assert_warn(sdp, !qd->qd_bh_count);
 
-                gfs2_lvb_unhold(qd->qd_gl);
+                gfs2_glock_put(qd->qd_gl);
                 kmem_cache_free(gfs2_quotad_cachep, qd);
 
                 spin_lock(&qd_lru_lock);