GFS2: Move glock superblock pointer to field gl_name

What uniquely identifies a glock in the glock hash table is not
gl_name, but gl_name and its superblock pointer. This patch makes
the gl_name field correspond to a unique glock identifier. That will
allow us to simplify hashing with a future patch, since the hash
algorithm can then take the gl_name and hash its components in one
operation.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Acked-by: Steven Whitehouse <swhiteho@redhat.com>
diff --git a/fs/gfs2/glops.c b/fs/gfs2/glops.c
index fa3fa5e..1f6c9c3 100644
--- a/fs/gfs2/glops.c
+++ b/fs/gfs2/glops.c
@@ -32,13 +32,15 @@
 
 static void gfs2_ail_error(struct gfs2_glock *gl, const struct buffer_head *bh)
 {
-	fs_err(gl->gl_sbd, "AIL buffer %p: blocknr %llu state 0x%08lx mapping %p page state 0x%lx\n",
+	fs_err(gl->gl_name.ln_sbd,
+	       "AIL buffer %p: blocknr %llu state 0x%08lx mapping %p page "
+	       "state 0x%lx\n",
 	       bh, (unsigned long long)bh->b_blocknr, bh->b_state,
 	       bh->b_page->mapping, bh->b_page->flags);
-	fs_err(gl->gl_sbd, "AIL glock %u:%llu mapping %p\n",
+	fs_err(gl->gl_name.ln_sbd, "AIL glock %u:%llu mapping %p\n",
 	       gl->gl_name.ln_type, gl->gl_name.ln_number,
 	       gfs2_glock2aspace(gl));
-	gfs2_lm_withdraw(gl->gl_sbd, "AIL error\n");
+	gfs2_lm_withdraw(gl->gl_name.ln_sbd, "AIL error\n");
 }
 
 /**
@@ -52,7 +54,7 @@
 static void __gfs2_ail_flush(struct gfs2_glock *gl, bool fsync,
 			     unsigned int nr_revokes)
 {
-	struct gfs2_sbd *sdp = gl->gl_sbd;
+	struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
 	struct list_head *head = &gl->gl_ail_list;
 	struct gfs2_bufdata *bd, *tmp;
 	struct buffer_head *bh;
@@ -80,7 +82,7 @@
 
 static void gfs2_ail_empty_gl(struct gfs2_glock *gl)
 {
-	struct gfs2_sbd *sdp = gl->gl_sbd;
+	struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
 	struct gfs2_trans tr;
 
 	memset(&tr, 0, sizeof(tr));
@@ -109,7 +111,7 @@
 
 void gfs2_ail_flush(struct gfs2_glock *gl, bool fsync)
 {
-	struct gfs2_sbd *sdp = gl->gl_sbd;
+	struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
 	unsigned int revokes = atomic_read(&gl->gl_ail_count);
 	unsigned int max_revokes = (sdp->sd_sb.sb_bsize - sizeof(struct gfs2_log_descriptor)) / sizeof(u64);
 	int ret;
@@ -139,7 +141,7 @@
 
 static void rgrp_go_sync(struct gfs2_glock *gl)
 {
-	struct gfs2_sbd *sdp = gl->gl_sbd;
+	struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
 	struct address_space *mapping = &sdp->sd_aspace;
 	struct gfs2_rgrpd *rgd;
 	int error;
@@ -179,7 +181,7 @@
 
 static void rgrp_go_inval(struct gfs2_glock *gl, int flags)
 {
-	struct gfs2_sbd *sdp = gl->gl_sbd;
+	struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
 	struct address_space *mapping = &sdp->sd_aspace;
 	struct gfs2_rgrpd *rgd = gl->gl_object;
 
@@ -218,7 +220,7 @@
 
 	GLOCK_BUG_ON(gl, gl->gl_state != LM_ST_EXCLUSIVE);
 
-	gfs2_log_flush(gl->gl_sbd, gl, NORMAL_FLUSH);
+	gfs2_log_flush(gl->gl_name.ln_sbd, gl, NORMAL_FLUSH);
 	filemap_fdatawrite(metamapping);
 	if (ip) {
 		struct address_space *mapping = ip->i_inode.i_mapping;
@@ -252,7 +254,7 @@
 {
 	struct gfs2_inode *ip = gl->gl_object;
 
-	gfs2_assert_withdraw(gl->gl_sbd, !atomic_read(&gl->gl_ail_count));
+	gfs2_assert_withdraw(gl->gl_name.ln_sbd, !atomic_read(&gl->gl_ail_count));
 
 	if (flags & DIO_METADATA) {
 		struct address_space *mapping = gfs2_glock2aspace(gl);
@@ -264,9 +266,9 @@
 		}
 	}
 
-	if (ip == GFS2_I(gl->gl_sbd->sd_rindex)) {
-		gfs2_log_flush(gl->gl_sbd, NULL, NORMAL_FLUSH);
-		gl->gl_sbd->sd_rindex_uptodate = 0;
+	if (ip == GFS2_I(gl->gl_name.ln_sbd->sd_rindex)) {
+		gfs2_log_flush(gl->gl_name.ln_sbd, NULL, NORMAL_FLUSH);
+		gl->gl_name.ln_sbd->sd_rindex_uptodate = 0;
 	}
 	if (ip && S_ISREG(ip->i_inode.i_mode))
 		truncate_inode_pages(ip->i_inode.i_mapping, 0);
@@ -281,7 +283,7 @@
 
 static int inode_go_demote_ok(const struct gfs2_glock *gl)
 {
-	struct gfs2_sbd *sdp = gl->gl_sbd;
+	struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
 	struct gfs2_holder *gh;
 
 	if (sdp->sd_jindex == gl->gl_object || sdp->sd_rindex == gl->gl_object)
@@ -416,7 +418,7 @@
 static int inode_go_lock(struct gfs2_holder *gh)
 {
 	struct gfs2_glock *gl = gh->gh_gl;
-	struct gfs2_sbd *sdp = gl->gl_sbd;
+	struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
 	struct gfs2_inode *ip = gl->gl_object;
 	int error = 0;
 
@@ -477,7 +479,7 @@
 static void freeze_go_sync(struct gfs2_glock *gl)
 {
 	int error = 0;
-	struct gfs2_sbd *sdp = gl->gl_sbd;
+	struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
 
 	if (gl->gl_state == LM_ST_SHARED &&
 	    test_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags)) {
@@ -500,7 +502,7 @@
 
 static int freeze_go_xmote_bh(struct gfs2_glock *gl, struct gfs2_holder *gh)
 {
-	struct gfs2_sbd *sdp = gl->gl_sbd;
+	struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
 	struct gfs2_inode *ip = GFS2_I(sdp->sd_jdesc->jd_inode);
 	struct gfs2_glock *j_gl = ip->i_gl;
 	struct gfs2_log_header_host head;
@@ -545,7 +547,7 @@
 static void iopen_go_callback(struct gfs2_glock *gl, bool remote)
 {
 	struct gfs2_inode *ip = (struct gfs2_inode *)gl->gl_object;
-	struct gfs2_sbd *sdp = gl->gl_sbd;
+	struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
 
 	if (!remote || (sdp->sd_vfs->s_flags & MS_RDONLY))
 		return;