Merge tag 'omapdss-for-3.7' of git://gitorious.org/linux-omap-dss2/linux into fbdev-next

Omapdss driver changes for the 3.7 merge window.

Notable changes:

* Basic writeback support for DISPC level. Writeback is not yet usable, though,
  as we need higher level code to actually expose the writeback feature to
  userspace.
* Rewriting the omapdss output drivers. We're trying to remove the hard links
  between the omapdss and the panels, and this rewrite work moves us closer to
  that goal.
* Cleanup and restructuring patches that have been made while working on device
  tree support for omapdss. Device tree support is still some way ahead, but
  these patches are good cleanups in themselves.
* Basic OMAP5 DSS support for DPI and DSI outputs.
* Workaround for the problem that GFX overlay's fifo is too small for high
  resolution scenarios, causing underflows.
* Cleanups that remove dependencies to omap platform code.

1 files changed, 128 insertions, 35 deletions

diff --git a/fs/btrfs/delayed-ref.c b/fs/btrfs/delayed-ref.c
index da7419ed01bb..ae9411773397 100644
--- a/fs/btrfs/delayed-ref.c
+++ b/fs/btrfs/delayed-ref.c
@@ -38,17 +38,14 @@
 static int comp_tree_refs(struct btrfs_delayed_tree_ref *ref2,
                           struct btrfs_delayed_tree_ref *ref1)
 {
-        if (ref1->node.type == BTRFS_TREE_BLOCK_REF_KEY) {
-                if (ref1->root < ref2->root)
-                        return -1;
-                if (ref1->root > ref2->root)
-                        return 1;
-        } else {
-                if (ref1->parent < ref2->parent)
-                        return -1;
-                if (ref1->parent > ref2->parent)
-                        return 1;
-        }
+        if (ref1->root < ref2->root)
+                return -1;
+        if (ref1->root > ref2->root)
+                return 1;
+        if (ref1->parent < ref2->parent)
+                return -1;
+        if (ref1->parent > ref2->parent)
+                return 1;
         return 0;
 }
 
@@ -85,7 +82,8 @@ static int comp_data_refs(struct btrfs_delayed_data_ref *ref2,
  * type of the delayed backrefs and content of delayed backrefs.
  */
 static int comp_entry(struct btrfs_delayed_ref_node *ref2,
-                      struct btrfs_delayed_ref_node *ref1)
+                      struct btrfs_delayed_ref_node *ref1,
+                      bool compare_seq)
 {
         if (ref1->bytenr < ref2->bytenr)
                 return -1;
@@ -102,10 +100,12 @@ static int comp_entry(struct btrfs_delayed_ref_node *ref2,
         if (ref1->type > ref2->type)
                 return 1;
         /* merging of sequenced refs is not allowed */
-        if (ref1->seq < ref2->seq)
-                return -1;
-        if (ref1->seq > ref2->seq)
-                return 1;
+        if (compare_seq) {
+                if (ref1->seq < ref2->seq)
+                        return -1;
+                if (ref1->seq > ref2->seq)
+                        return 1;
+        }
         if (ref1->type == BTRFS_TREE_BLOCK_REF_KEY ||
             ref1->type == BTRFS_SHARED_BLOCK_REF_KEY) {
                 return comp_tree_refs(btrfs_delayed_node_to_tree_ref(ref2),
@@ -139,7 +139,7 @@ static struct btrfs_delayed_ref_node *tree_insert(struct rb_root *root,
                 entry = rb_entry(parent_node, struct btrfs_delayed_ref_node,
                                  rb_node);
 
-                cmp = comp_entry(entry, ins);
+                cmp = comp_entry(entry, ins, 1);
                 if (cmp < 0)
                         p = &(*p)->rb_left;
                 else if (cmp > 0)
@@ -233,6 +233,114 @@ int btrfs_delayed_ref_lock(struct btrfs_trans_handle *trans,
         return 0;
 }
 
+static void inline drop_delayed_ref(struct btrfs_trans_handle *trans,
+                                    struct btrfs_delayed_ref_root *delayed_refs,
+                                    struct btrfs_delayed_ref_node *ref)
+{
+        rb_erase(&ref->rb_node, &delayed_refs->root);
+        ref->in_tree = 0;
+        btrfs_put_delayed_ref(ref);
+        delayed_refs->num_entries--;
+        if (trans->delayed_ref_updates)
+                trans->delayed_ref_updates--;
+}
+
+static int merge_ref(struct btrfs_trans_handle *trans,
+                     struct btrfs_delayed_ref_root *delayed_refs,
+                     struct btrfs_delayed_ref_node *ref, u64 seq)
+{
+        struct rb_node *node;
+        int merged = 0;
+        int mod = 0;
+        int done = 0;
+
+        node = rb_prev(&ref->rb_node);
+        while (node) {
+                struct btrfs_delayed_ref_node *next;
+
+                next = rb_entry(node, struct btrfs_delayed_ref_node, rb_node);
+                node = rb_prev(node);
+                if (next->bytenr != ref->bytenr)
+                        break;
+                if (seq && next->seq >= seq)
+                        break;
+                if (comp_entry(ref, next, 0))
+                        continue;
+
+                if (ref->action == next->action) {
+                        mod = next->ref_mod;
+                } else {
+                        if (ref->ref_mod < next->ref_mod) {
+                                struct btrfs_delayed_ref_node *tmp;
+
+                                tmp = ref;
+                                ref = next;
+                                next = tmp;
+                                done = 1;
+                        }
+                        mod = -next->ref_mod;
+                }
+
+                merged++;
+                drop_delayed_ref(trans, delayed_refs, next);
+                ref->ref_mod += mod;
+                if (ref->ref_mod == 0) {
+                        drop_delayed_ref(trans, delayed_refs, ref);
+                        break;
+                } else {
+                        /*
+                         * You can't have multiples of the same ref on a tree
+                         * block.
+                         */
+                        WARN_ON(ref->type == BTRFS_TREE_BLOCK_REF_KEY ||
+                                ref->type == BTRFS_SHARED_BLOCK_REF_KEY);
+                }
+
+                if (done)
+                        break;
+                node = rb_prev(&ref->rb_node);
+        }
+
+        return merged;
+}
+
+void btrfs_merge_delayed_refs(struct btrfs_trans_handle *trans,
+                              struct btrfs_fs_info *fs_info,
+                              struct btrfs_delayed_ref_root *delayed_refs,
+                              struct btrfs_delayed_ref_head *head)
+{
+        struct rb_node *node;
+        u64 seq = 0;
+
+        spin_lock(&fs_info->tree_mod_seq_lock);
+        if (!list_empty(&fs_info->tree_mod_seq_list)) {
+                struct seq_list *elem;
+
+                elem = list_first_entry(&fs_info->tree_mod_seq_list,
+                                        struct seq_list, list);
+                seq = elem->seq;
+        }
+        spin_unlock(&fs_info->tree_mod_seq_lock);
+
+        node = rb_prev(&head->node.rb_node);
+        while (node) {
+                struct btrfs_delayed_ref_node *ref;
+
+                ref = rb_entry(node, struct btrfs_delayed_ref_node,
+                               rb_node);
+                if (ref->bytenr != head->node.bytenr)
+                        break;
+
+                /* We can't merge refs that are outside of our seq count */
+                if (seq && ref->seq >= seq)
+                        break;
+                if (merge_ref(trans, delayed_refs, ref, seq))
+                        node = rb_prev(&head->node.rb_node);
+                else
+                        node = rb_prev(node);
+        }
+}
+
 int btrfs_check_delayed_seq(struct btrfs_fs_info *fs_info,
                             struct btrfs_delayed_ref_root *delayed_refs,
                             u64 seq)
@@ -336,18 +444,11 @@ update_existing_ref(struct btrfs_trans_handle *trans,
                  * every changing the extent allocation tree.
                  */
                 existing->ref_mod--;
-                if (existing->ref_mod == 0) {
-                        rb_erase(&existing->rb_node,
-                                 &delayed_refs->root);
-                        existing->in_tree = 0;
-                        btrfs_put_delayed_ref(existing);
-                        delayed_refs->num_entries--;
-                        if (trans->delayed_ref_updates)
-                                trans->delayed_ref_updates--;
-                } else {
+                if (existing->ref_mod == 0)
+                        drop_delayed_ref(trans, delayed_refs, existing);
+                else
                         WARN_ON(existing->type == BTRFS_TREE_BLOCK_REF_KEY ||
                                 existing->type == BTRFS_SHARED_BLOCK_REF_KEY);
-                }
         } else {
                 WARN_ON(existing->type == BTRFS_TREE_BLOCK_REF_KEY ||
                         existing->type == BTRFS_SHARED_BLOCK_REF_KEY);
@@ -662,9 +763,6 @@ int btrfs_add_delayed_tree_ref(struct btrfs_fs_info *fs_info,
         add_delayed_tree_ref(fs_info, trans, &ref->node, bytenr,
                                    num_bytes, parent, ref_root, level, action,
                                    for_cow);
-        if (!need_ref_seq(for_cow, ref_root) &&
-            waitqueue_active(&fs_info->tree_mod_seq_wait))
-                wake_up(&fs_info->tree_mod_seq_wait);
         spin_unlock(&delayed_refs->lock);
         if (need_ref_seq(for_cow, ref_root))
                 btrfs_qgroup_record_ref(trans, &ref->node, extent_op);
@@ -713,9 +811,6 @@ int btrfs_add_delayed_data_ref(struct btrfs_fs_info *fs_info,
         add_delayed_data_ref(fs_info, trans, &ref->node, bytenr,
                                    num_bytes, parent, ref_root, owner, offset,
                                    action, for_cow);
-        if (!need_ref_seq(for_cow, ref_root) &&
-            waitqueue_active(&fs_info->tree_mod_seq_wait))
-                wake_up(&fs_info->tree_mod_seq_wait);
         spin_unlock(&delayed_refs->lock);
         if (need_ref_seq(for_cow, ref_root))
                 btrfs_qgroup_record_ref(trans, &ref->node, extent_op);
@@ -744,8 +839,6 @@ int btrfs_add_delayed_extent_op(struct btrfs_fs_info *fs_info,
                                    num_bytes, BTRFS_UPDATE_DELAYED_HEAD,
                                    extent_op->is_data);
 
-        if (waitqueue_active(&fs_info->tree_mod_seq_wait))
-                wake_up(&fs_info->tree_mod_seq_wait);
         spin_unlock(&delayed_refs->lock);
         return 0;
 }