Btrfs: Maintain a list of inodes that are delalloc and a way to wait on them

Signed-off-by: Chris Mason <chris.mason@oracle.com>

1 files changed, 41 insertions, 6 deletions

diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 640648c66b22..8a405a5fa6a3 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -303,6 +303,10 @@ int btrfs_set_bit_hook(struct inode *inode, u64 start, u64 end,
                 spin_lock_irqsave(&root->fs_info->delalloc_lock, flags);
                 BTRFS_I(inode)->delalloc_bytes += end - start + 1;
                 root->fs_info->delalloc_bytes += end - start + 1;
+                if (list_empty(&BTRFS_I(inode)->delalloc_inodes)) {
+                        list_add_tail(&BTRFS_I(inode)->delalloc_inodes,
+                                      &root->fs_info->delalloc_inodes);
+                }
                 spin_unlock_irqrestore(&root->fs_info->delalloc_lock, flags);
         }
         return 0;
@@ -325,6 +329,10 @@ int btrfs_clear_bit_hook(struct inode *inode, u64 start, u64 end,
                         root->fs_info->delalloc_bytes -= end - start + 1;
                         BTRFS_I(inode)->delalloc_bytes -= end - start + 1;
                 }
+                if (BTRFS_I(inode)->delalloc_bytes == 0 &&
+                    !list_empty(&BTRFS_I(inode)->delalloc_inodes)) {
+                        list_del_init(&BTRFS_I(inode)->delalloc_inodes);
+                }
                 spin_unlock_irqrestore(&root->fs_info->delalloc_lock, flags);
         }
         return 0;
@@ -408,6 +416,12 @@ static noinline int add_pending_csums(struct btrfs_trans_handle *trans,
         return 0;
 }
 
+int btrfs_set_extent_delalloc(struct inode *inode, u64 start, u64 end)
+{
+        return set_extent_delalloc(&BTRFS_I(inode)->io_tree, start, end,
+                                   GFP_NOFS);
+}
+
 struct btrfs_writepage_fixup {
         struct page *page;
         struct btrfs_work work;
@@ -453,8 +467,7 @@ again:
                 goto again;
         }
 
-        set_extent_delalloc(&BTRFS_I(inode)->io_tree, page_start, page_end,
-                            GFP_NOFS);
+        btrfs_set_extent_delalloc(inode, page_start, page_end);
         ClearPageChecked(page);
 out:
         unlock_extent(&BTRFS_I(inode)->io_tree, page_start, page_end, GFP_NOFS);
@@ -1530,8 +1543,7 @@ again:
                 goto again;
         }
 
-        set_extent_delalloc(&BTRFS_I(inode)->io_tree, page_start,
-                            page_end, GFP_NOFS);
+        btrfs_set_extent_delalloc(inode, page_start, page_end);
         ret = 0;
         if (offset != PAGE_CACHE_SIZE) {
                 kaddr = kmap(page);
@@ -1766,6 +1778,7 @@ static int btrfs_init_locked_inode(struct inode *inode, void *p)
                              inode->i_mapping, GFP_NOFS);
         extent_io_tree_init(&BTRFS_I(inode)->io_failure_tree,
                              inode->i_mapping, GFP_NOFS);
+        INIT_LIST_HEAD(&BTRFS_I(inode)->delalloc_inodes);
         btrfs_ordered_inode_tree_init(&BTRFS_I(inode)->ordered_tree);
         mutex_init(&BTRFS_I(inode)->csum_mutex);
         mutex_init(&BTRFS_I(inode)->extent_mutex);
@@ -2158,6 +2171,7 @@ static struct inode *btrfs_new_inode(struct btrfs_trans_handle *trans,
         extent_io_tree_init(&BTRFS_I(inode)->io_failure_tree,
                              inode->i_mapping, GFP_NOFS);
         btrfs_ordered_inode_tree_init(&BTRFS_I(inode)->ordered_tree);
+        INIT_LIST_HEAD(&BTRFS_I(inode)->delalloc_inodes);
         mutex_init(&BTRFS_I(inode)->csum_mutex);
         mutex_init(&BTRFS_I(inode)->extent_mutex);
         BTRFS_I(inode)->delalloc_bytes = 0;
@@ -2400,6 +2414,7 @@ static int btrfs_create(struct inode *dir, struct dentry *dentry,
                                      inode->i_mapping, GFP_NOFS);
                 extent_io_tree_init(&BTRFS_I(inode)->io_failure_tree,
                                      inode->i_mapping, GFP_NOFS);
+                INIT_LIST_HEAD(&BTRFS_I(inode)->delalloc_inodes);
                 mutex_init(&BTRFS_I(inode)->csum_mutex);
                 mutex_init(&BTRFS_I(inode)->extent_mutex);
                 BTRFS_I(inode)->delalloc_bytes = 0;
@@ -3049,8 +3064,7 @@ again:
                 goto again;
         }
 
-        set_extent_delalloc(&BTRFS_I(inode)->io_tree, page_start,
-                            page_end, GFP_NOFS);
+        btrfs_set_extent_delalloc(inode, page_start, page_end);
         ret = 0;
 
         /* page is wholly or partially inside EOF */
@@ -3373,6 +3387,26 @@ out_unlock:
         return ret;
 }
 
+int btrfs_start_delalloc_inodes(struct btrfs_root *root)
+{
+        struct list_head *head = &root->fs_info->delalloc_inodes;
+        struct btrfs_inode *binode;
+        unsigned long flags;
+
+        spin_lock_irqsave(&root->fs_info->delalloc_lock, flags);
+        while(!list_empty(head)) {
+                binode = list_entry(head->next, struct btrfs_inode,
+                                    delalloc_inodes);
+                atomic_inc(&binode->vfs_inode.i_count);
+                spin_unlock_irqrestore(&root->fs_info->delalloc_lock, flags);
+                filemap_write_and_wait(binode->vfs_inode.i_mapping);
+                iput(&binode->vfs_inode);
+                spin_lock_irqsave(&root->fs_info->delalloc_lock, flags);
+        }
+        spin_unlock_irqrestore(&root->fs_info->delalloc_lock, flags);
+        return 0;
+}
+
 static int btrfs_symlink(struct inode *dir, struct dentry *dentry,
                          const char *symname)
 {
@@ -3436,6 +3470,7 @@ static int btrfs_symlink(struct inode *dir, struct dentry *dentry,
                                      inode->i_mapping, GFP_NOFS);
                 extent_io_tree_init(&BTRFS_I(inode)->io_failure_tree,
                                      inode->i_mapping, GFP_NOFS);
+                INIT_LIST_HEAD(&BTRFS_I(inode)->delalloc_inodes);
                 mutex_init(&BTRFS_I(inode)->csum_mutex);
                 mutex_init(&BTRFS_I(inode)->extent_mutex);
                 BTRFS_I(inode)->delalloc_bytes = 0;