GFS2: eliminate log elements and simplify

This patch eliminates the gfs2_log_element data structure and
rolls its two components into the gfs2_bufdata. This makes the code
easier to understand and makes it easier to migrate to a rbtree
to keep the list sorted.

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

1 files changed, 19 insertions, 22 deletions

diff --git a/fs/gfs2/lops.c b/fs/gfs2/lops.c
index 11fedb569225..852c1be1dd3b 100644
--- a/fs/gfs2/lops.c
+++ b/fs/gfs2/lops.c
@@ -388,9 +388,8 @@ static struct page *gfs2_get_log_desc(struct gfs2_sbd *sdp, u32 ld_type,
         return page;
 }
 
-static void buf_lo_add(struct gfs2_sbd *sdp, struct gfs2_log_element *le)
+static void buf_lo_add(struct gfs2_sbd *sdp, struct gfs2_bufdata *bd)
 {
-        struct gfs2_bufdata *bd = container_of(le, struct gfs2_bufdata, bd_le);
         struct gfs2_meta_header *mh;
         struct gfs2_trans *tr;
 
@@ -398,7 +397,7 @@ static void buf_lo_add(struct gfs2_sbd *sdp, struct gfs2_log_element *le)
         gfs2_log_lock(sdp);
         tr = current->journal_info;
         tr->tr_touched = 1;
-        if (!list_empty(&le->le_list))
+        if (!list_empty(&bd->bd_list))
                 goto out;
         set_bit(GLF_LFLUSH, &bd->bd_gl->gl_flags);
         set_bit(GLF_DIRTY, &bd->bd_gl->gl_flags);
@@ -408,7 +407,7 @@ static void buf_lo_add(struct gfs2_sbd *sdp, struct gfs2_log_element *le)
         mh->__pad0 = cpu_to_be64(0);
         mh->mh_jid = cpu_to_be32(sdp->sd_jdesc->jd_jid);
         sdp->sd_log_num_buf++;
-        list_add(&le->le_list, &sdp->sd_log_le_buf);
+        list_add(&bd->bd_list, &sdp->sd_log_le_buf);
         tr->tr_num_buf_new++;
 out:
         gfs2_log_unlock(sdp);
@@ -440,7 +439,7 @@ static void gfs2_before_commit(struct gfs2_sbd *sdp, unsigned int limit,
         __be64 *ptr;
 
         gfs2_log_lock(sdp);
-        bd1 = bd2 = list_prepare_entry(bd1, blist, bd_le.le_list);
+        bd1 = bd2 = list_prepare_entry(bd1, blist, bd_list);
         while(total) {
                 num = total;
                 if (total > limit)
@@ -452,7 +451,7 @@ static void gfs2_before_commit(struct gfs2_sbd *sdp, unsigned int limit,
                 ptr = (__be64 *)(ld + 1);
 
                 n = 0;
-                list_for_each_entry_continue(bd1, blist, bd_le.le_list) {
+                list_for_each_entry_continue(bd1, blist, bd_list) {
                         *ptr++ = cpu_to_be64(bd1->bd_bh->b_blocknr);
                         if (is_databuf) {
                                 gfs2_check_magic(bd1->bd_bh);
@@ -467,7 +466,7 @@ static void gfs2_before_commit(struct gfs2_sbd *sdp, unsigned int limit,
                 gfs2_log_lock(sdp);
 
                 n = 0;
-                list_for_each_entry_continue(bd2, blist, bd_le.le_list) {
+                list_for_each_entry_continue(bd2, blist, bd_list) {
                         get_bh(bd2->bd_bh);
                         gfs2_log_unlock(sdp);
                         lock_buffer(bd2->bd_bh);
@@ -513,8 +512,8 @@ static void buf_lo_after_commit(struct gfs2_sbd *sdp, struct gfs2_ail *ai)
         struct gfs2_bufdata *bd;
 
         while (!list_empty(head)) {
-                bd = list_entry(head->next, struct gfs2_bufdata, bd_le.le_list);
-                list_del_init(&bd->bd_le.le_list);
+                bd = list_entry(head->next, struct gfs2_bufdata, bd_list);
+                list_del_init(&bd->bd_list);
                 sdp->sd_log_num_buf--;
 
                 gfs2_unpin(sdp, bd->bd_bh, ai);
@@ -601,9 +600,8 @@ static void buf_lo_after_scan(struct gfs2_jdesc *jd, int error, int pass)
                 jd->jd_jid, sdp->sd_replayed_blocks, sdp->sd_found_blocks);
 }
 
-static void revoke_lo_add(struct gfs2_sbd *sdp, struct gfs2_log_element *le)
+static void revoke_lo_add(struct gfs2_sbd *sdp, struct gfs2_bufdata *bd)
 {
-        struct gfs2_bufdata *bd = container_of(le, struct gfs2_bufdata, bd_le);
         struct gfs2_glock *gl = bd->bd_gl;
         struct gfs2_trans *tr;
 
@@ -613,7 +611,7 @@ static void revoke_lo_add(struct gfs2_sbd *sdp, struct gfs2_log_element *le)
         sdp->sd_log_num_revoke++;
         atomic_inc(&gl->gl_revokes);
         set_bit(GLF_LFLUSH, &gl->gl_flags);
-        list_add(&le->le_list, &sdp->sd_log_le_revoke);
+        list_add(&bd->bd_list, &sdp->sd_log_le_revoke);
 }
 
 static void revoke_lo_before_commit(struct gfs2_sbd *sdp)
@@ -634,7 +632,7 @@ static void revoke_lo_before_commit(struct gfs2_sbd *sdp)
         ld = page_address(page);
         offset = sizeof(struct gfs2_log_descriptor);
 
-        list_for_each_entry(bd, head, bd_le.le_list) {
+        list_for_each_entry(bd, head, bd_list) {
                 sdp->sd_log_num_revoke--;
 
                 if (offset + sizeof(u64) > sdp->sd_sb.sb_bsize) {
@@ -664,8 +662,8 @@ static void revoke_lo_after_commit(struct gfs2_sbd *sdp, struct gfs2_ail *ai)
         struct gfs2_glock *gl;
 
         while (!list_empty(head)) {
-                bd = list_entry(head->next, struct gfs2_bufdata, bd_le.le_list);
-                list_del_init(&bd->bd_le.le_list);
+                bd = list_entry(head->next, struct gfs2_bufdata, bd_list);
+                list_del_init(&bd->bd_list);
                 gl = bd->bd_gl;
                 atomic_dec(&gl->gl_revokes);
                 clear_bit(GLF_LFLUSH, &gl->gl_flags);
@@ -768,9 +766,8 @@ static void revoke_lo_after_scan(struct gfs2_jdesc *jd, int error, int pass)
  *    blocks, which isn't an enormous overhead but twice as much as
  *    for normal metadata blocks.
  */
-static void databuf_lo_add(struct gfs2_sbd *sdp, struct gfs2_log_element *le)
+static void databuf_lo_add(struct gfs2_sbd *sdp, struct gfs2_bufdata *bd)
 {
-        struct gfs2_bufdata *bd = container_of(le, struct gfs2_bufdata, bd_le);
         struct gfs2_trans *tr = current->journal_info;
         struct address_space *mapping = bd->bd_bh->b_page->mapping;
         struct gfs2_inode *ip = GFS2_I(mapping->host);
@@ -779,7 +776,7 @@ static void databuf_lo_add(struct gfs2_sbd *sdp, struct gfs2_log_element *le)
         gfs2_log_lock(sdp);
         if (tr)
                 tr->tr_touched = 1;
-        if (!list_empty(&le->le_list))
+        if (!list_empty(&bd->bd_list))
                 goto out;
         set_bit(GLF_LFLUSH, &bd->bd_gl->gl_flags);
         set_bit(GLF_DIRTY, &bd->bd_gl->gl_flags);
@@ -787,9 +784,9 @@ static void databuf_lo_add(struct gfs2_sbd *sdp, struct gfs2_log_element *le)
                 gfs2_pin(sdp, bd->bd_bh);
                 tr->tr_num_databuf_new++;
                 sdp->sd_log_num_databuf++;
-                list_add_tail(&le->le_list, &sdp->sd_log_le_databuf);
+                list_add_tail(&bd->bd_list, &sdp->sd_log_le_databuf);
         } else {
-                list_add_tail(&le->le_list, &sdp->sd_log_le_ordered);
+                list_add_tail(&bd->bd_list, &sdp->sd_log_le_ordered);
         }
 out:
         gfs2_log_unlock(sdp);
@@ -885,8 +882,8 @@ static void databuf_lo_after_commit(struct gfs2_sbd *sdp, struct gfs2_ail *ai)
         struct gfs2_bufdata *bd;
 
         while (!list_empty(head)) {
-                bd = list_entry(head->next, struct gfs2_bufdata, bd_le.le_list);
-                list_del_init(&bd->bd_le.le_list);
+                bd = list_entry(head->next, struct gfs2_bufdata, bd_list);
+                list_del_init(&bd->bd_list);
                 sdp->sd_log_num_databuf--;
                 gfs2_unpin(sdp, bd->bd_bh, ai);
         }