Btrfs: cleanup destroy_marked_extents

We can just look up the extent_buffers for the range and free stuff that way.
This makes the cleanup a bit cleaner and we can make sure to evict the
extent_buffers pretty quickly by marking them as stale.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>

3 files changed, 11 insertions, 32 deletions

diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index b20f1121efae..aff571cb6e04 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -3752,13 +3752,9 @@ static int btrfs_destroy_marked_extents(struct btrfs_root *root,
                                         int mark)
 {
         int ret;
-        struct page *page;
-        struct inode *btree_inode = root->fs_info->btree_inode;
         struct extent_buffer *eb;
         u64 start = 0;
         u64 end;
-        u64 offset;
-        unsigned long index;
 
         while (1) {
                 ret = find_first_extent_bit(dirty_pages, start, &start, &end,
@@ -3768,35 +3764,17 @@ static int btrfs_destroy_marked_extents(struct btrfs_root *root,
 
                 clear_extent_bits(dirty_pages, start, end, mark, GFP_NOFS);
                 while (start <= end) {
-                        index = start >> PAGE_CACHE_SHIFT;
-                        start = (u64)(index + 1) << PAGE_CACHE_SHIFT;
-                        page = find_get_page(btree_inode->i_mapping, index);
-                        if (!page)
+                        eb = btrfs_find_tree_block(root, start,
+                                                   root->leafsize);
+                        start += eb->len;
+                        if (!eb)
                                 continue;
-                        offset = page_offset(page);
-
-                        spin_lock(&dirty_pages->buffer_lock);
-                        eb = radix_tree_lookup(
-                             &(&BTRFS_I(page->mapping->host)->io_tree)->buffer,
-                                               offset >> PAGE_CACHE_SHIFT);
-                        spin_unlock(&dirty_pages->buffer_lock);
-                        if (eb)
-                                ret = test_and_clear_bit(EXTENT_BUFFER_DIRTY,
-                                                         &eb->bflags);
-                        lock_page(page);
-
-                        wait_on_page_writeback(page);
-                        if (PageDirty(page)) {
-                                clear_page_dirty_for_io(page);
-                                spin_lock_irq(&page->mapping->tree_lock);
-                                radix_tree_tag_clear(&page->mapping->page_tree,
-                                                        page_index(page),
-                                                        PAGECACHE_TAG_DIRTY);
-                                spin_unlock_irq(&page->mapping->tree_lock);
-                        }
+                        wait_on_extent_buffer_writeback(eb);
 
-                        unlock_page(page);
-                        page_cache_release(page);
+                        if (test_and_clear_bit(EXTENT_BUFFER_DIRTY,
+                                               &eb->bflags))
+                                clear_extent_buffer_dirty(eb);
+                        free_extent_buffer_stale(eb);
                 }
         }
 
diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index 2107a06679c5..d9a82f261e04 100644
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -3162,7 +3162,7 @@ static int eb_wait(void *word)
         return 0;
 }
 
-static void wait_on_extent_buffer_writeback(struct extent_buffer *eb)
+void wait_on_extent_buffer_writeback(struct extent_buffer *eb)
 {
         wait_on_bit(&eb->bflags, EXTENT_BUFFER_WRITEBACK, eb_wait,
                     TASK_UNINTERRUPTIBLE);
diff --git a/fs/btrfs/extent_io.h b/fs/btrfs/extent_io.h
index db009d80bef4..fa86861de244 100644
--- a/fs/btrfs/extent_io.h
+++ b/fs/btrfs/extent_io.h
@@ -282,6 +282,7 @@ void free_extent_buffer_stale(struct extent_buffer *eb);
 int read_extent_buffer_pages(struct extent_io_tree *tree,
                              struct extent_buffer *eb, u64 start, int wait,
                              get_extent_t *get_extent, int mirror_num);
+void wait_on_extent_buffer_writeback(struct extent_buffer *eb);
 
 static inline unsigned long num_extent_pages(u64 start, u64 len)
 {