From d352ac68148b69937d39ca5d48bcc4478e118dbf Mon Sep 17 00:00:00 2001 From: Chris Mason Date: Mon, 29 Sep 2008 15:18:18 -0400 Subject: Btrfs: add and improve comments This improves the comments at the top of many functions. It didn't dive into the guts of functions because I was trying to avoid merging problems with the new allocator and back reference work. extent-tree.c and volumes.c were both skipped, and there is definitely more work todo in cleaning and commenting the code. Signed-off-by: Chris Mason --- fs/btrfs/ordered-data.c | 19 ++++++++++++++++++- 1 file changed, 18 insertions(+), 1 deletion(-) (limited to 'fs/btrfs/ordered-data.c') diff --git a/fs/btrfs/ordered-data.c b/fs/btrfs/ordered-data.c index 951eacff2420..dcc1730dd837 100644 --- a/fs/btrfs/ordered-data.c +++ b/fs/btrfs/ordered-data.c @@ -26,7 +26,6 @@ #include "btrfs_inode.h" #include "extent_io.h" - static u64 entry_end(struct btrfs_ordered_extent *entry) { if (entry->file_offset + entry->len < entry->file_offset) @@ -34,6 +33,9 @@ static u64 entry_end(struct btrfs_ordered_extent *entry) return entry->file_offset + entry->len; } +/* returns NULL if the insertion worked, or it returns the node it did find + * in the tree + */ static struct rb_node *tree_insert(struct rb_root *root, u64 file_offset, struct rb_node *node) { @@ -58,6 +60,10 @@ static struct rb_node *tree_insert(struct rb_root *root, u64 file_offset, return NULL; } +/* + * look for a given offset in the tree, and if it can't be found return the + * first lesser offset + */ static struct rb_node *__tree_search(struct rb_root *root, u64 file_offset, struct rb_node **prev_ret) { @@ -108,6 +114,9 @@ static struct rb_node *__tree_search(struct rb_root *root, u64 file_offset, return NULL; } +/* + * helper to check if a given offset is inside a given entry + */ static int offset_in_entry(struct btrfs_ordered_extent *entry, u64 file_offset) { if (file_offset < entry->file_offset || @@ -116,6 +125,10 @@ static int offset_in_entry(struct btrfs_ordered_extent *entry, u64 file_offset) return 1; } +/* + * look find the first ordered struct that has this offset, otherwise + * the first one less than this offset + */ static inline struct rb_node *tree_search(struct btrfs_ordered_inode_tree *tree, u64 file_offset) { @@ -305,6 +318,10 @@ int btrfs_remove_ordered_extent(struct inode *inode, return 0; } +/* + * wait for all the ordered extents in a root. This is done when balancing + * space between drives. + */ int btrfs_wait_ordered_extents(struct btrfs_root *root, int nocow_only) { struct list_head splice; -- cgit v1.2.3