1 files changed, 36 insertions, 44 deletions

diff --git a/fs/btrfs/free-space-cache.c b/fs/btrfs/free-space-cache.c
index 7a15fcfb3e1f..6e5b7e463698 100644
--- a/fs/btrfs/free-space-cache.c
+++ b/fs/btrfs/free-space-cache.c
@@ -351,6 +351,11 @@ static int io_ctl_prepare_pages(struct io_ctl *io_ctl, struct inode *inode,
                 }
         }
 
+        for (i = 0; i < io_ctl->num_pages; i++) {
+                clear_page_dirty_for_io(io_ctl->pages[i]);
+                set_page_extent_mapped(io_ctl->pages[i]);
+        }
+
         return 0;
 }
 
@@ -537,6 +542,13 @@ static int io_ctl_read_entry(struct io_ctl *io_ctl,
                             struct btrfs_free_space *entry, u8 *type)
 {
         struct btrfs_free_space_entry *e;
+        int ret;
+
+        if (!io_ctl->cur) {
+                ret = io_ctl_check_crc(io_ctl, io_ctl->index);
+                if (ret)
+                        return ret;
+        }
 
         e = io_ctl->cur;
         entry->offset = le64_to_cpu(e->offset);
@@ -550,10 +562,7 @@ static int io_ctl_read_entry(struct io_ctl *io_ctl,
 
         io_ctl_unmap_page(io_ctl);
 
-        if (io_ctl->index >= io_ctl->num_pages)
-                return 0;
-
-        return io_ctl_check_crc(io_ctl, io_ctl->index);
+        return 0;
 }
 
 static int io_ctl_read_bitmap(struct io_ctl *io_ctl,
@@ -561,9 +570,6 @@ static int io_ctl_read_bitmap(struct io_ctl *io_ctl,
 {
         int ret;
 
-        if (io_ctl->cur && io_ctl->cur != io_ctl->orig)
-                io_ctl_unmap_page(io_ctl);
-
         ret = io_ctl_check_crc(io_ctl, io_ctl->index);
         if (ret)
                 return ret;
@@ -699,6 +705,8 @@ int __load_free_space_cache(struct btrfs_root *root, struct inode *inode,
                 num_entries--;
         }
 
+        io_ctl_unmap_page(&io_ctl);
+
         /*
          * We add the bitmaps at the end of the entries in order that
          * the bitmap entries are added to the cache.
@@ -1841,7 +1849,13 @@ again:
                 info = tree_search_offset(ctl, offset_to_bitmap(ctl, offset),
                                           1, 0);
                 if (!info) {
-                        WARN_ON(1);
+                        /* the tree logging code might be calling us before we
+                         * have fully loaded the free space rbtree for this
+                         * block group.  So it is possible the entry won't
+                         * be in the rbtree yet at all.  The caching code
+                         * will make sure not to put it in the rbtree if
+                         * the logging code has pinned it.
+                         */
                         goto out_lock;
                 }
         }
@@ -2448,16 +2462,23 @@ setup_cluster_bitmap(struct btrfs_block_group_cache *block_group,
 {
         struct btrfs_free_space_ctl *ctl = block_group->free_space_ctl;
         struct btrfs_free_space *entry;
-        struct rb_node *node;
         int ret = -ENOSPC;
+        u64 bitmap_offset = offset_to_bitmap(ctl, offset);
 
         if (ctl->total_bitmaps == 0)
                 return -ENOSPC;
 
         /*
-         * First check our cached list of bitmaps and see if there is an entry
-         * here that will work.
+         * The bitmap that covers offset won't be in the list unless offset
+         * is just its start offset.
          */
+        entry = list_first_entry(bitmaps, struct btrfs_free_space, list);
+        if (entry->offset != bitmap_offset) {
+                entry = tree_search_offset(ctl, bitmap_offset, 1, 0);
+                if (entry && list_empty(&entry->list))
+                        list_add(&entry->list, bitmaps);
+        }
+
         list_for_each_entry(entry, bitmaps, list) {
                 if (entry->bytes < min_bytes)
                         continue;
@@ -2468,38 +2489,10 @@ setup_cluster_bitmap(struct btrfs_block_group_cache *block_group,
         }
 
         /*
-         * If we do have entries on our list and we are here then we didn't find
-         * anything, so go ahead and get the next entry after the last entry in
-         * this list and start the search from there.
+         * The bitmaps list has all the bitmaps that record free space
+         * starting after offset, so no more search is required.
          */
-        if (!list_empty(bitmaps)) {
-                entry = list_entry(bitmaps->prev, struct btrfs_free_space,
-                                   list);
-                node = rb_next(&entry->offset_index);
-                if (!node)
-                        return -ENOSPC;
-                entry = rb_entry(node, struct btrfs_free_space, offset_index);
-                goto search;
-        }
-
-        entry = tree_search_offset(ctl, offset_to_bitmap(ctl, offset), 0, 1);
-        if (!entry)
-                return -ENOSPC;
-
-search:
-        node = &entry->offset_index;
-        do {
-                entry = rb_entry(node, struct btrfs_free_space, offset_index);
-                node = rb_next(&entry->offset_index);
-                if (!entry->bitmap)
-                        continue;
-                if (entry->bytes < min_bytes)
-                        continue;
-                ret = btrfs_bitmap_cluster(block_group, entry, cluster, offset,
-                                           bytes, min_bytes);
-        } while (ret && node);
-
-        return ret;
+        return -ENOSPC;
 }
 
 /*
@@ -2517,8 +2510,8 @@ int btrfs_find_space_cluster(struct btrfs_trans_handle *trans,
                              u64 offset, u64 bytes, u64 empty_size)
 {
         struct btrfs_free_space_ctl *ctl = block_group->free_space_ctl;
-        struct list_head bitmaps;
         struct btrfs_free_space *entry, *tmp;
+        LIST_HEAD(bitmaps);
         u64 min_bytes;
         int ret;
 
@@ -2557,7 +2550,6 @@ int btrfs_find_space_cluster(struct btrfs_trans_handle *trans,
                 goto out;
         }
 
-        INIT_LIST_HEAD(&bitmaps);
         ret = setup_cluster_no_bitmap(block_group, cluster, &bitmaps, offset,
                                       bytes, min_bytes);
         if (ret)