From a52d9a8033c454cd9b4697cfafb467509fc1693f Mon Sep 17 00:00:00 2001 From: Chris Mason Date: Mon, 27 Aug 2007 16:49:44 -0400 Subject: Btrfs: Extent based page cache code. This uses an rbtree of extents and tests instead of buffer heads. Signed-off-by: Chris Mason --- fs/btrfs/extent_map.h | 89 +++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 89 insertions(+) create mode 100644 fs/btrfs/extent_map.h (limited to 'fs/btrfs/extent_map.h') diff --git a/fs/btrfs/extent_map.h b/fs/btrfs/extent_map.h new file mode 100644 index 000000000000..108944aab4bd --- /dev/null +++ b/fs/btrfs/extent_map.h @@ -0,0 +1,89 @@ +#ifndef __EXTENTMAP__ +#define __EXTENTMAP__ + +#include + +#define EXTENT_MAP_INLINE (u64)-2 +#define EXTENT_MAP_DELALLOC (u64)-1 + +struct extent_map_tree { + struct rb_root map; + struct rb_root state; + struct address_space *mapping; + rwlock_t lock; +}; + +/* note, this must start with the same fields as fs/extent_map.c:tree_entry */ +struct extent_map { + u64 start; + u64 end; /* inclusive */ + int in_tree; + struct rb_node rb_node; + /* block_start and block_end are in bytes */ + u64 block_start; + u64 block_end; /* inclusive */ + struct block_device *bdev; + atomic_t refs; +}; + +/* note, this must start with the same fields as fs/extent_map.c:tree_entry */ +struct extent_state { + u64 start; + u64 end; /* inclusive */ + int in_tree; + struct rb_node rb_node; + wait_queue_head_t wq; + atomic_t refs; + unsigned long state; + struct list_head list; +}; + +struct extent_buffer { + u64 start; + u64 end; /* inclusive */ + char *addr; + struct page *pages[]; +}; + +typedef struct extent_map *(get_extent_t)(struct inode *inode, + struct page *page, + size_t page_offset, + u64 start, u64 end, + int create); + +void extent_map_tree_init(struct extent_map_tree *tree, + struct address_space *mapping, gfp_t mask); +struct extent_map *lookup_extent_mapping(struct extent_map_tree *tree, + u64 start, u64 end); +int add_extent_mapping(struct extent_map_tree *tree, + struct extent_map *em); +int remove_extent_mapping(struct extent_map_tree *tree, struct extent_map *em); +int try_release_extent_mapping(struct extent_map_tree *tree, struct page *page); +int lock_extent(struct extent_map_tree *tree, u64 start, u64 end, gfp_t mask); +int unlock_extent(struct extent_map_tree *tree, u64 start, u64 end, gfp_t mask); +struct extent_map *alloc_extent_map(gfp_t mask); +void free_extent_map(struct extent_map *em); +int extent_read_full_page(struct extent_map_tree *tree, struct page *page, + get_extent_t *get_extent); +void __init extent_map_init(void); +void __exit extent_map_exit(void); +int extent_clean_all_trees(struct extent_map_tree *tree); +int set_extent_uptodate(struct extent_map_tree *tree, u64 start, u64 end, + gfp_t mask); +int set_extent_new(struct extent_map_tree *tree, u64 start, u64 end, + gfp_t mask); +int set_extent_dirty(struct extent_map_tree *tree, u64 start, u64 end, + gfp_t mask); +int extent_invalidatepage(struct extent_map_tree *tree, + struct page *page, unsigned long offset); +int extent_write_full_page(struct extent_map_tree *tree, struct page *page, + get_extent_t *get_extent, + struct writeback_control *wbc); +int extent_prepare_write(struct extent_map_tree *tree, + struct inode *inode, struct page *page, + unsigned from, unsigned to, get_extent_t *get_extent); +int extent_commit_write(struct extent_map_tree *tree, + struct inode *inode, struct page *page, + unsigned from, unsigned to); +int set_range_dirty(struct extent_map_tree *tree, u64 start, u64 end); +#endif -- cgit v1.2.3-70-g09d2