1 files changed, 81 insertions, 24 deletions

diff --git a/fs/btrfs/ordered-data.c b/fs/btrfs/ordered-data.c
index 5799bc46a309..9b16073bb875 100644
--- a/fs/btrfs/ordered-data.c
+++ b/fs/btrfs/ordered-data.c
@@ -291,16 +291,16 @@ int btrfs_put_ordered_extent(struct btrfs_ordered_extent *entry)
 
 /*
  * remove an ordered extent from the tree.  No references are dropped
- * but, anyone waiting on this extent is woken up.
+ * and you must wake_up entry->wait.  You must hold the tree mutex
+ * while you call this function.
  */
-int btrfs_remove_ordered_extent(struct inode *inode,
+static int __btrfs_remove_ordered_extent(struct inode *inode,
                                 struct btrfs_ordered_extent *entry)
 {
         struct btrfs_ordered_inode_tree *tree;
         struct rb_node *node;
 
         tree = &BTRFS_I(inode)->ordered_tree;
-        mutex_lock(&tree->mutex);
         node = &entry->rb_node;
         rb_erase(node, &tree->tree);
         tree->last = NULL;
@@ -326,9 +326,26 @@ int btrfs_remove_ordered_extent(struct inode *inode,
         }
         spin_unlock(&BTRFS_I(inode)->root->fs_info->ordered_extent_lock);
 
+        return 0;
+}
+
+/*
+ * remove an ordered extent from the tree.  No references are dropped
+ * but any waiters are woken.
+ */
+int btrfs_remove_ordered_extent(struct inode *inode,
+                                struct btrfs_ordered_extent *entry)
+{
+        struct btrfs_ordered_inode_tree *tree;
+        int ret;
+
+        tree = &BTRFS_I(inode)->ordered_tree;
+        mutex_lock(&tree->mutex);
+        ret = __btrfs_remove_ordered_extent(inode, entry);
         mutex_unlock(&tree->mutex);
         wake_up(&entry->wait);
-        return 0;
+
+        return ret;
 }
 
 /*
@@ -589,7 +606,7 @@ out:
  * After an extent is done, call this to conditionally update the on disk
  * i_size.  i_size is updated to cover any fully written part of the file.
  */
-int btrfs_ordered_update_i_size(struct inode *inode,
+int btrfs_ordered_update_i_size(struct inode *inode, u64 offset,
                                 struct btrfs_ordered_extent *ordered)
 {
         struct btrfs_ordered_inode_tree *tree = &BTRFS_I(inode)->ordered_tree;
@@ -597,18 +614,30 @@ int btrfs_ordered_update_i_size(struct inode *inode,
         u64 disk_i_size;
         u64 new_i_size;
         u64 i_size_test;
+        u64 i_size = i_size_read(inode);
         struct rb_node *node;
+        struct rb_node *prev = NULL;
         struct btrfs_ordered_extent *test;
+        int ret = 1;
+
+        if (ordered)
+                offset = entry_end(ordered);
 
         mutex_lock(&tree->mutex);
         disk_i_size = BTRFS_I(inode)->disk_i_size;
 
+        /* truncate file */
+        if (disk_i_size > i_size) {
+                BTRFS_I(inode)->disk_i_size = i_size;
+                ret = 0;
+                goto out;
+        }
+
         /*
          * if the disk i_size is already at the inode->i_size, or
          * this ordered extent is inside the disk i_size, we're done
          */
-        if (disk_i_size >= inode->i_size ||
-            ordered->file_offset + ordered->len <= disk_i_size) {
+        if (disk_i_size == i_size || offset <= disk_i_size) {
                 goto out;
         }
 
@@ -616,8 +645,7 @@ int btrfs_ordered_update_i_size(struct inode *inode,
          * we can't update the disk_isize if there are delalloc bytes
          * between disk_i_size and  this ordered extent
          */
-        if (test_range_bit(io_tree, disk_i_size,
-                           ordered->file_offset + ordered->len - 1,
+        if (test_range_bit(io_tree, disk_i_size, offset - 1,
                            EXTENT_DELALLOC, 0, NULL)) {
                 goto out;
         }
@@ -626,20 +654,32 @@ int btrfs_ordered_update_i_size(struct inode *inode,
          * if we find an ordered extent then we can't update disk i_size
          * yet
          */
-        node = &ordered->rb_node;
-        while (1) {
-                node = rb_prev(node);
-                if (!node)
-                        break;
+        if (ordered) {
+                node = rb_prev(&ordered->rb_node);
+        } else {
+                prev = tree_search(tree, offset);
+                /*
+                 * we insert file extents without involving ordered struct,
+                 * so there should be no ordered struct cover this offset
+                 */
+                if (prev) {
+                        test = rb_entry(prev, struct btrfs_ordered_extent,
+                                        rb_node);
+                        BUG_ON(offset_in_entry(test, offset));
+                }
+                node = prev;
+        }
+        while (node) {
                 test = rb_entry(node, struct btrfs_ordered_extent, rb_node);
                 if (test->file_offset + test->len <= disk_i_size)
                         break;
-                if (test->file_offset >= inode->i_size)
+                if (test->file_offset >= i_size)
                         break;
                 if (test->file_offset >= disk_i_size)
                         goto out;
+                node = rb_prev(node);
         }
-        new_i_size = min_t(u64, entry_end(ordered), i_size_read(inode));
+        new_i_size = min_t(u64, offset, i_size);
 
         /*
          * at this point, we know we can safely update i_size to at least
@@ -647,7 +687,14 @@ int btrfs_ordered_update_i_size(struct inode *inode,
          * walk forward and see if ios from higher up in the file have
          * finished.
          */
-        node = rb_next(&ordered->rb_node);
+        if (ordered) {
+                node = rb_next(&ordered->rb_node);
+        } else {
+                if (prev)
+                        node = rb_next(prev);
+                else
+                        node = rb_first(&tree->tree);
+        }
         i_size_test = 0;
         if (node) {
                 /*
@@ -655,10 +702,10 @@ int btrfs_ordered_update_i_size(struct inode *inode,
                  * between our ordered extent and the next one.
                  */
                 test = rb_entry(node, struct btrfs_ordered_extent, rb_node);
-                if (test->file_offset > entry_end(ordered))
+                if (test->file_offset > offset)
                         i_size_test = test->file_offset;
         } else {
-                i_size_test = i_size_read(inode);
+                i_size_test = i_size;
         }
 
         /*
@@ -667,15 +714,25 @@ int btrfs_ordered_update_i_size(struct inode *inode,
          * are no delalloc bytes in this area, it is safe to update
          * disk_i_size to the end of the region.
          */
-        if (i_size_test > entry_end(ordered) &&
-            !test_range_bit(io_tree, entry_end(ordered), i_size_test - 1,
-                           EXTENT_DELALLOC, 0, NULL)) {
-                new_i_size = min_t(u64, i_size_test, i_size_read(inode));
+        if (i_size_test > offset &&
+            !test_range_bit(io_tree, offset, i_size_test - 1,
+                            EXTENT_DELALLOC, 0, NULL)) {
+                new_i_size = min_t(u64, i_size_test, i_size);
         }
         BTRFS_I(inode)->disk_i_size = new_i_size;
+        ret = 0;
 out:
+        /*
+         * we need to remove the ordered extent with the tree lock held
+         * so that other people calling this function don't find our fully
+         * processed ordered entry and skip updating the i_size
+         */
+        if (ordered)
+                __btrfs_remove_ordered_extent(inode, ordered);
         mutex_unlock(&tree->mutex);
-        return 0;
+        if (ordered)
+                wake_up(&ordered->wait);
+        return ret;
 }
 
 /*