Commit e349fd3b authored by Josef Bacik's avatar Josef Bacik Committed by David Sterba
Browse files

btrfs: make tree_search_for_insert return extent_state 



We use this to search for an extent state, or return the nodes we need
to insert a new extent state.  This means we have the following pattern

node = tree_search_for_insert();
if (!node) {
	/* alloc and insert. */
	goto again;
}
state = rb_entry(node, struct extent_state, rb_node);

we don't use the node for anything else.  Making
tree_search_for_insert() return the extent_state means we can drop the
rb_node and clean this up by eliminating the rb_entry.

Signed-off-by: default avatarJosef Bacik <josef@toxicpanda.com>
Reviewed-by: default avatarDavid Sterba <dsterba@suse.com>
Signed-off-by: default avatarDavid Sterba <dsterba@suse.com>
parent aa852dab

fs/btrfs/extent-io-tree.c

+16 −28
Original line number Diff line number Diff line
@@ -221,7 +221,7 @@ static inline struct extent_state *next_state(struct extent_state *state) 
 * If no such entry exists, return pointer to entry that ends before @offset

 * and fill parameters @node_ret and @parent_ret, ie. does not return NULL.

 */

static inline struct rb_node *tree_search_for_insert(struct extent_io_tree *tree,

static inline struct extent_state *tree_search_for_insert(struct extent_io_tree *tree,

							  u64 offset,

							  struct rb_node ***node_ret,

							  struct rb_node **parent_ret)
@@ -229,7 +229,7 @@ static inline struct rb_node *tree_search_for_insert(struct extent_io_tree *tree 
	struct rb_root *root = &tree->state;

	struct rb_node **node = &root->rb_node;

	struct rb_node *prev = NULL;

	struct extent_state *entry;

	struct extent_state *entry = NULL;



	while (*node) {

		prev = *node;
@@ -240,7 +240,7 @@ static inline struct rb_node *tree_search_for_insert(struct extent_io_tree *tree 
		else if (offset > entry->end)

			node = &(*node)->rb_right;

		else

			return *node;

			return entry;

	}



	if (node_ret)
@@ -249,12 +249,10 @@ static inline struct rb_node *tree_search_for_insert(struct extent_io_tree *tree 
		*parent_ret = prev;



	/* Search neighbors until we find the first one past the end */

	while (prev && offset > entry->end) {

		prev = rb_next(prev);

		entry = rb_entry(prev, struct extent_state, rb_node);

	}

	while (entry && offset > entry->end)

		entry = next_state(entry);



	return prev;

	return entry;

}



/*
@@ -318,9 +316,7 @@ static inline struct rb_node *tree_search_prev_next(struct extent_io_tree *tree, 
 */

static inline struct extent_state *tree_search(struct extent_io_tree *tree, u64 offset)

{

	struct rb_node *node = tree_search_for_insert(tree, offset, NULL, NULL);



	return (node) ? rb_entry(node, struct extent_state, rb_node) : NULL;

	return tree_search_for_insert(tree, offset, NULL, NULL);

}



static void extent_io_tree_panic(struct extent_io_tree *tree, int err)
@@ -970,7 +966,6 @@ int set_extent_bit(struct extent_io_tree *tree, u64 start, u64 end, u32 bits, 
{

	struct extent_state *state;

	struct extent_state *prealloc = NULL;

	struct rb_node *node;

	struct rb_node **p;

	struct rb_node *parent;

	int err = 0;
@@ -1000,17 +995,15 @@ int set_extent_bit(struct extent_io_tree *tree, u64 start, u64 end, u32 bits, 
	if (cached_state && *cached_state) {

		state = *cached_state;

		if (state->start <= start && state->end > start &&

		    extent_state_in_tree(state)) {

			node = &state->rb_node;

		    extent_state_in_tree(state))

			goto hit_next;

	}

	}

	/*

	 * This search will find all the extents that end after our range

	 * starts.

	 */

	node = tree_search_for_insert(tree, start, &p, &parent);

	if (!node) {

	state = tree_search_for_insert(tree, start, &p, &parent);

	if (!state) {

		prealloc = alloc_extent_state_atomic(prealloc);

		BUG_ON(!prealloc);

		prealloc->start = start;
@@ -1020,7 +1013,6 @@ int set_extent_bit(struct extent_io_tree *tree, u64 start, u64 end, u32 bits, 
		prealloc = NULL;

		goto out;

	}

	state = rb_entry(node, struct extent_state, rb_node);

hit_next:

	last_start = state->start;

	last_end = state->end;
@@ -1205,7 +1197,6 @@ int convert_extent_bit(struct extent_io_tree *tree, u64 start, u64 end, 
{

	struct extent_state *state;

	struct extent_state *prealloc = NULL;

	struct rb_node *node;

	struct rb_node **p;

	struct rb_node *parent;

	int err = 0;
@@ -1235,18 +1226,16 @@ int convert_extent_bit(struct extent_io_tree *tree, u64 start, u64 end, 
	if (cached_state && *cached_state) {

		state = *cached_state;

		if (state->start <= start && state->end > start &&

		    extent_state_in_tree(state)) {

			node = &state->rb_node;

		    extent_state_in_tree(state))

			goto hit_next;

	}

	}



	/*

	 * This search will find all the extents that end after our range

	 * starts.

	 */

	node = tree_search_for_insert(tree, start, &p, &parent);

	if (!node) {

	state = tree_search_for_insert(tree, start, &p, &parent);

	if (!state) {

		prealloc = alloc_extent_state_atomic(prealloc);

		if (!prealloc) {

			err = -ENOMEM;
@@ -1259,7 +1248,6 @@ int convert_extent_bit(struct extent_io_tree *tree, u64 start, u64 end, 
		prealloc = NULL;

		goto out;

	}

	state = rb_entry(node, struct extent_state, rb_node);

hit_next:

	last_start = state->start;

	last_end = state->end;