Btrfs: Fix hole insertion corner cases
There were a few places that could cause duplicate extent insertion,
this adjusts the code that creates holes to avoid it.
lookup_extent_map is changed to correctly return all of the extents in a
range, even when there are none matching at the start of the range.
Signed-off-by: Chris Mason <chris.mason@oracle.com>
diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c
index 897242e..1cd8c90 100644
--- a/fs/btrfs/file.c
+++ b/fs/btrfs/file.c
@@ -278,7 +278,7 @@
u64 hole_size;
u64 mask = root->sectorsize - 1;
last_pos_in_file = (isize + mask) & ~mask;
- hole_size = (start_pos - last_pos_in_file + mask) & ~mask;
+ hole_size = (end_pos - last_pos_in_file + mask) & ~mask;
if (last_pos_in_file < start_pos) {
err = btrfs_drop_extents(trans, root, inode,
@@ -293,6 +293,7 @@
inode->i_ino,
last_pos_in_file,
0, 0, hole_size);
+ btrfs_check_file(root, inode);
}
if (err)
goto failed;
@@ -378,6 +379,80 @@
return 0;
}
+int btrfs_check_file(struct btrfs_root *root, struct inode *inode)
+{
+ return 0;
+#if 0
+ struct btrfs_path *path;
+ struct btrfs_key found_key;
+ struct extent_buffer *leaf;
+ struct btrfs_file_extent_item *extent;
+ u64 last_offset = 0;
+ int nritems;
+ int slot;
+ int found_type;
+ int ret;
+ int err = 0;
+ u64 extent_end = 0;
+
+ path = btrfs_alloc_path();
+ ret = btrfs_lookup_file_extent(NULL, root, path, inode->i_ino,
+ last_offset, 0);
+ while(1) {
+ nritems = btrfs_header_nritems(path->nodes[0]);
+ if (path->slots[0] >= nritems) {
+ ret = btrfs_next_leaf(root, path);
+ if (ret)
+ goto out;
+ nritems = btrfs_header_nritems(path->nodes[0]);
+ }
+ slot = path->slots[0];
+ leaf = path->nodes[0];
+ btrfs_item_key_to_cpu(leaf, &found_key, slot);
+ if (found_key.objectid != inode->i_ino)
+ break;
+ if (found_key.type != BTRFS_EXTENT_DATA_KEY)
+ goto out;
+
+ if (found_key.offset != last_offset) {
+ WARN_ON(1);
+ btrfs_print_leaf(root, leaf);
+ printk("inode %lu found offset %Lu expected %Lu\n",
+ inode->i_ino, found_key.offset, last_offset);
+ err = 1;
+ goto out;
+ }
+ extent = btrfs_item_ptr(leaf, slot,
+ struct btrfs_file_extent_item);
+ found_type = btrfs_file_extent_type(leaf, extent);
+ if (found_type == BTRFS_FILE_EXTENT_REG) {
+ extent_end = found_key.offset +
+ btrfs_file_extent_num_bytes(leaf, extent);
+ } else if (found_type == BTRFS_FILE_EXTENT_INLINE) {
+ struct btrfs_item *item;
+ item = btrfs_item_nr(leaf, slot);
+ extent_end = found_key.offset +
+ btrfs_file_extent_inline_len(leaf, item);
+ extent_end = (extent_end + root->sectorsize - 1) &
+ ~((u64)root->sectorsize -1 );
+ }
+ last_offset = extent_end;
+ path->slots[0]++;
+ }
+ if (last_offset < inode->i_size) {
+ WARN_ON(1);
+ btrfs_print_leaf(root, leaf);
+ printk("inode %lu found offset %Lu size %Lu\n", inode->i_ino,
+ last_offset, inode->i_size);
+ err = 1;
+
+ }
+out:
+ btrfs_free_path(path);
+ return err;
+#endif
+}
+
/*
* this is very complex, but the basic idea is to drop all extents
* in the range start - end. hint_block is filled in with a block number
@@ -436,6 +511,7 @@
slot = path->slots[0];
ret = 0;
btrfs_item_key_to_cpu(leaf, &key, slot);
+
if (key.offset >= end || key.objectid != inode->i_ino) {
goto out;
}