From d1310b2e0cd98eb1348553e69b73827b436dca7b Mon Sep 17 00:00:00 2001 From: Chris Mason Date: Thu, 24 Jan 2008 16:13:08 -0500 Subject: Btrfs: Split the extent_map code into two parts There is now extent_map for mapping offsets in the file to disk and extent_io for state tracking, IO submission and extent_bufers. The new extent_map code shifts from [start,end] pairs to [start,len], and pushes the locking out into the caller. This allows a few performance optimizations and is easier to use. A number of extent_map usage bugs were fixed, mostly with failing to remove extent_map entries when changing the file. Signed-off-by: Chris Mason --- fs/btrfs/inode.c | 175 +++++++++++++++++++++++++++++-------------------------- 1 file changed, 92 insertions(+), 83 deletions(-) (limited to 'fs/btrfs/inode.c') diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index 67005480e139..16d3aef45d18 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -53,7 +53,7 @@ static struct inode_operations btrfs_file_inode_operations; static struct address_space_operations btrfs_aops; static struct address_space_operations btrfs_symlink_aops; static struct file_operations btrfs_dir_file_operations; -static struct extent_map_ops btrfs_extent_map_ops; +static struct extent_io_ops btrfs_extent_io_ops; static struct kmem_cache *btrfs_inode_cachep; struct kmem_cache *btrfs_trans_handle_cachep; @@ -104,6 +104,8 @@ static int cow_file_range(struct inode *inode, u64 start, u64 end) u64 num_bytes; u64 cur_alloc_size; u64 blocksize = root->sectorsize; + u64 orig_start = start; + u64 orig_num_bytes; struct btrfs_key ins; int ret; @@ -115,6 +117,7 @@ static int cow_file_range(struct inode *inode, u64 start, u64 end) num_bytes = max(blocksize, num_bytes); ret = btrfs_drop_extents(trans, root, inode, start, start + num_bytes, start, &alloc_hint); + orig_num_bytes = num_bytes; if (alloc_hint == EXTENT_MAP_INLINE) goto out; @@ -138,6 +141,8 @@ static int cow_file_range(struct inode *inode, u64 start, u64 end) alloc_hint = ins.objectid + ins.offset; start += cur_alloc_size; } + btrfs_drop_extent_cache(inode, orig_start, + orig_start + orig_num_bytes - 1); btrfs_add_ordered_inode(inode); out: btrfs_end_transaction(trans, root); @@ -297,7 +302,7 @@ int btrfs_readpage_io_hook(struct page *page, u64 start, u64 end) int ret = 0; struct inode *inode = page->mapping->host; struct btrfs_root *root = BTRFS_I(inode)->root; - struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree; + struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree; struct btrfs_csum_item *item; struct btrfs_path *path = NULL; u32 csum; @@ -317,7 +322,7 @@ int btrfs_readpage_io_hook(struct page *page, u64 start, u64 end) } read_extent_buffer(path->nodes[0], &csum, (unsigned long)item, BTRFS_CRC32_SIZE); - set_state_private(em_tree, start, csum); + set_state_private(io_tree, start, csum); out: if (path) btrfs_free_path(path); @@ -329,17 +334,19 @@ int btrfs_readpage_end_io_hook(struct page *page, u64 start, u64 end) { size_t offset = start - ((u64)page->index << PAGE_CACHE_SHIFT); struct inode *inode = page->mapping->host; - struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree; + struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree; char *kaddr; u64 private; int ret; struct btrfs_root *root = BTRFS_I(inode)->root; u32 csum = ~(u32)0; unsigned long flags; + if (btrfs_test_opt(root, NODATASUM) || btrfs_test_flag(inode, NODATASUM)) return 0; - ret = get_state_private(em_tree, start, &private); + + ret = get_state_private(io_tree, start, &private); local_irq_save(flags); kaddr = kmap_atomic(page, KM_IRQ0); if (ret) { @@ -428,7 +435,7 @@ void btrfs_read_locked_inode(struct inode *inode) switch (inode->i_mode & S_IFMT) { case S_IFREG: inode->i_mapping->a_ops = &btrfs_aops; - BTRFS_I(inode)->extent_tree.ops = &btrfs_extent_map_ops; + BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops; inode->i_fop = &btrfs_file_operations; inode->i_op = &btrfs_file_inode_operations; break; @@ -873,7 +880,7 @@ static int btrfs_cow_one_page(struct inode *inode, struct page *page, size_t zero_start) { char *kaddr; - struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree; + struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree; struct btrfs_root *root = BTRFS_I(inode)->root; u64 page_start = (u64)page->index << PAGE_CACHE_SHIFT; u64 page_end = page_start + PAGE_CACHE_SIZE - 1; @@ -884,12 +891,12 @@ static int btrfs_cow_one_page(struct inode *inode, struct page *page, WARN_ON(!PageLocked(page)); set_page_extent_mapped(page); - lock_extent(em_tree, page_start, page_end, GFP_NOFS); + lock_extent(io_tree, page_start, page_end, GFP_NOFS); delalloc_start = page_start; - existing_delalloc = count_range_bits(&BTRFS_I(inode)->extent_tree, + existing_delalloc = count_range_bits(&BTRFS_I(inode)->io_tree, &delalloc_start, page_end, PAGE_CACHE_SIZE, EXTENT_DELALLOC); - set_extent_delalloc(&BTRFS_I(inode)->extent_tree, page_start, + set_extent_delalloc(&BTRFS_I(inode)->io_tree, page_start, page_end, GFP_NOFS); spin_lock(&root->fs_info->delalloc_lock); @@ -903,7 +910,7 @@ static int btrfs_cow_one_page(struct inode *inode, struct page *page, kunmap(page); } set_page_dirty(page); - unlock_extent(em_tree, page_start, page_end, GFP_NOFS); + unlock_extent(io_tree, page_start, page_end, GFP_NOFS); return ret; } @@ -961,7 +968,7 @@ static int btrfs_setattr(struct dentry *dentry, struct iattr *attr) attr->ia_valid & ATTR_SIZE && attr->ia_size > inode->i_size) { struct btrfs_trans_handle *trans; struct btrfs_root *root = BTRFS_I(inode)->root; - struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree; + struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree; u64 mask = root->sectorsize - 1; u64 pos = (inode->i_size + mask) & ~mask; @@ -986,7 +993,7 @@ static int btrfs_setattr(struct dentry *dentry, struct iattr *attr) btrfs_truncate_page(inode->i_mapping, inode->i_size); - lock_extent(em_tree, pos, block_end, GFP_NOFS); + lock_extent(io_tree, pos, block_end, GFP_NOFS); hole_size = block_end - hole_start; mutex_lock(&root->fs_info->fs_mutex); @@ -1001,11 +1008,13 @@ static int btrfs_setattr(struct dentry *dentry, struct iattr *attr) inode->i_ino, hole_start, 0, 0, hole_size); + btrfs_drop_extent_cache(inode, hole_start, + hole_size - 1); btrfs_check_file(root, inode); } btrfs_end_transaction(trans, root); mutex_unlock(&root->fs_info->fs_mutex); - unlock_extent(em_tree, pos, block_end, GFP_NOFS); + unlock_extent(io_tree, pos, block_end, GFP_NOFS); if (err) return err; } @@ -1189,7 +1198,8 @@ static int btrfs_init_locked_inode(struct inode *inode, void *p) struct btrfs_iget_args *args = p; inode->i_ino = args->ino; BTRFS_I(inode)->root = args->root; - extent_map_tree_init(&BTRFS_I(inode)->extent_tree, + extent_map_tree_init(&BTRFS_I(inode)->extent_tree, GFP_NOFS); + extent_io_tree_init(&BTRFS_I(inode)->io_tree, inode->i_mapping, GFP_NOFS); return 0; } @@ -1485,7 +1495,8 @@ static struct inode *btrfs_new_inode(struct btrfs_trans_handle *trans, if (!inode) return ERR_PTR(-ENOMEM); - extent_map_tree_init(&BTRFS_I(inode)->extent_tree, + extent_map_tree_init(&BTRFS_I(inode)->extent_tree, GFP_NOFS); + extent_io_tree_init(&BTRFS_I(inode)->io_tree, inode->i_mapping, GFP_NOFS); BTRFS_I(inode)->root = root; @@ -1672,9 +1683,10 @@ static int btrfs_create(struct inode *dir, struct dentry *dentry, inode->i_mapping->a_ops = &btrfs_aops; inode->i_fop = &btrfs_file_operations; inode->i_op = &btrfs_file_inode_operations; - extent_map_tree_init(&BTRFS_I(inode)->extent_tree, + extent_map_tree_init(&BTRFS_I(inode)->extent_tree, GFP_NOFS); + extent_io_tree_init(&BTRFS_I(inode)->io_tree, inode->i_mapping, GFP_NOFS); - BTRFS_I(inode)->extent_tree.ops = &btrfs_extent_map_ops; + BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops; } dir->i_sb->s_dirt = 1; btrfs_update_inode_block_group(trans, inode); @@ -1816,7 +1828,7 @@ out_unlock: } struct extent_map *btrfs_get_extent(struct inode *inode, struct page *page, - size_t page_offset, u64 start, u64 end, + size_t page_offset, u64 start, u64 len, int create) { int ret; @@ -1826,7 +1838,6 @@ struct extent_map *btrfs_get_extent(struct inode *inode, struct page *page, u64 extent_end = 0; u64 objectid = inode->i_ino; u32 found_type; - int failed_insert = 0; struct btrfs_path *path; struct btrfs_root *root = BTRFS_I(inode)->root; struct btrfs_file_extent_item *item; @@ -1834,6 +1845,7 @@ struct extent_map *btrfs_get_extent(struct inode *inode, struct page *page, struct btrfs_key found_key; struct extent_map *em = NULL; struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree; + struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree; struct btrfs_trans_handle *trans = NULL; path = btrfs_alloc_path(); @@ -1841,24 +1853,26 @@ struct extent_map *btrfs_get_extent(struct inode *inode, struct page *page, mutex_lock(&root->fs_info->fs_mutex); again: - em = lookup_extent_mapping(em_tree, start, end); + spin_lock(&em_tree->lock); + em = lookup_extent_mapping(em_tree, start, len); + spin_unlock(&em_tree->lock); + if (em) { if (em->start > start) { - printk("get_extent start %Lu em start %Lu\n", - start, em->start); + printk("get_extent lookup [%Lu %Lu] em [%Lu %Lu]\n", + start, len, em->start, em->len); WARN_ON(1); } goto out; } + em = alloc_extent_map(GFP_NOFS); if (!em) { - em = alloc_extent_map(GFP_NOFS); - if (!em) { - err = -ENOMEM; - goto out; - } - em->start = EXTENT_MAP_HOLE; - em->end = EXTENT_MAP_HOLE; + err = -ENOMEM; + goto out; } + + em->start = EXTENT_MAP_HOLE; + em->len = (u64)-1; em->bdev = inode->i_sb->s_bdev; ret = btrfs_lookup_file_extent(trans, root, path, objectid, start, trans != NULL); @@ -1893,28 +1907,25 @@ again: if (start < extent_start || start >= extent_end) { em->start = start; if (start < extent_start) { - if (end < extent_start) + if (start + len <= extent_start) goto not_found; - em->end = extent_end - 1; + em->len = extent_end - extent_start; } else { - em->end = end; + em->len = len; } goto not_found_em; } bytenr = btrfs_file_extent_disk_bytenr(leaf, item); if (bytenr == 0) { em->start = extent_start; - em->end = extent_end - 1; + em->len = extent_end - extent_start; em->block_start = EXTENT_MAP_HOLE; - em->block_end = EXTENT_MAP_HOLE; goto insert; } bytenr += btrfs_file_extent_offset(leaf, item); em->block_start = bytenr; - em->block_end = em->block_start + - btrfs_file_extent_num_bytes(leaf, item) - 1; em->start = extent_start; - em->end = extent_end - 1; + em->len = extent_end - extent_start; goto insert; } else if (found_type == BTRFS_FILE_EXTENT_INLINE) { unsigned long ptr; @@ -1925,25 +1936,24 @@ again: size = btrfs_file_extent_inline_len(leaf, btrfs_item_nr(leaf, path->slots[0])); - extent_end = (extent_start + size - 1) | - ((u64)root->sectorsize - 1); + extent_end = (extent_start + size + root->sectorsize - 1) & + ~((u64)root->sectorsize - 1); if (start < extent_start || start >= extent_end) { em->start = start; if (start < extent_start) { - if (end < extent_start) + if (start + len <= extent_start) goto not_found; - em->end = extent_end; + em->len = extent_end - extent_start; } else { - em->end = end; + em->len = len; } goto not_found_em; } em->block_start = EXTENT_MAP_INLINE; - em->block_end = EXTENT_MAP_INLINE; if (!page) { em->start = extent_start; - em->end = extent_start + size - 1; + em->len = size; goto out; } @@ -1952,8 +1962,7 @@ again: copy_size = min_t(u64, PAGE_CACHE_SIZE - page_offset, size - extent_offset); em->start = extent_start + extent_offset; - em->end = (em->start + copy_size -1) | - ((u64)root->sectorsize -1); + em->len = copy_size; map = kmap(page); ptr = btrfs_file_extent_inline_start(item) + extent_offset; if (create == 0 && !PageUptodate(page)) { @@ -1974,7 +1983,8 @@ again: btrfs_mark_buffer_dirty(leaf); } kunmap(page); - set_extent_uptodate(em_tree, em->start, em->end, GFP_NOFS); + set_extent_uptodate(io_tree, em->start, + extent_map_end(em) - 1, GFP_NOFS); goto insert; } else { printk("unkknown found_type %d\n", found_type); @@ -1982,33 +1992,29 @@ again: } not_found: em->start = start; - em->end = end; + em->len = len; not_found_em: em->block_start = EXTENT_MAP_HOLE; - em->block_end = EXTENT_MAP_HOLE; insert: btrfs_release_path(root, path); - if (em->start > start || em->end < start) { - printk("bad extent! em: [%Lu %Lu] passed [%Lu %Lu]\n", em->start, em->end, start, end); + if (em->start > start || extent_map_end(em) <= start) { + printk("bad extent! em: [%Lu %Lu] passed [%Lu %Lu]\n", em->start, em->len, start, len); err = -EIO; goto out; } + + err = 0; + spin_lock(&em_tree->lock); ret = add_extent_mapping(em_tree, em); if (ret == -EEXIST) { free_extent_map(em); - em = NULL; - if (0 && failed_insert == 1) { - btrfs_drop_extent_cache(inode, start, end); - } - failed_insert++; - if (failed_insert > 5) { - printk("failing to insert %Lu %Lu\n", start, end); + em = lookup_extent_mapping(em_tree, start, len); + if (!em) { err = -EIO; - goto out; + printk("failing to insert %Lu %Lu\n", start, len); } - goto again; } - err = 0; + spin_unlock(&em_tree->lock); out: btrfs_free_path(path); if (trans) { @@ -2032,14 +2038,14 @@ static sector_t btrfs_bmap(struct address_space *mapping, sector_t iblock) int btrfs_readpage(struct file *file, struct page *page) { - struct extent_map_tree *tree; - tree = &BTRFS_I(page->mapping->host)->extent_tree; + struct extent_io_tree *tree; + tree = &BTRFS_I(page->mapping->host)->io_tree; return extent_read_full_page(tree, page, btrfs_get_extent); } static int btrfs_writepage(struct page *page, struct writeback_control *wbc) { - struct extent_map_tree *tree; + struct extent_io_tree *tree; if (current->flags & PF_MEMALLOC) { @@ -2047,15 +2053,15 @@ static int btrfs_writepage(struct page *page, struct writeback_control *wbc) unlock_page(page); return 0; } - tree = &BTRFS_I(page->mapping->host)->extent_tree; + tree = &BTRFS_I(page->mapping->host)->io_tree; return extent_write_full_page(tree, page, btrfs_get_extent, wbc); } static int btrfs_writepages(struct address_space *mapping, struct writeback_control *wbc) { - struct extent_map_tree *tree; - tree = &BTRFS_I(mapping->host)->extent_tree; + struct extent_io_tree *tree; + tree = &BTRFS_I(mapping->host)->io_tree; return extent_writepages(tree, mapping, btrfs_get_extent, wbc); } @@ -2063,19 +2069,21 @@ static int btrfs_readpages(struct file *file, struct address_space *mapping, struct list_head *pages, unsigned nr_pages) { - struct extent_map_tree *tree; - tree = &BTRFS_I(mapping->host)->extent_tree; + struct extent_io_tree *tree; + tree = &BTRFS_I(mapping->host)->io_tree; return extent_readpages(tree, mapping, pages, nr_pages, btrfs_get_extent); } static int btrfs_releasepage(struct page *page, gfp_t unused_gfp_flags) { - struct extent_map_tree *tree; + struct extent_io_tree *tree; + struct extent_map_tree *map; int ret; - tree = &BTRFS_I(page->mapping->host)->extent_tree; - ret = try_release_extent_mapping(tree, page); + tree = &BTRFS_I(page->mapping->host)->io_tree; + map = &BTRFS_I(page->mapping->host)->extent_tree; + ret = try_release_extent_mapping(map, tree, page); if (ret == 1) { ClearPagePrivate(page); set_page_private(page, 0); @@ -2086,9 +2094,9 @@ static int btrfs_releasepage(struct page *page, gfp_t unused_gfp_flags) static void btrfs_invalidatepage(struct page *page, unsigned long offset) { - struct extent_map_tree *tree; + struct extent_io_tree *tree; - tree = &BTRFS_I(page->mapping->host)->extent_tree; + tree = &BTRFS_I(page->mapping->host)->io_tree; extent_invalidatepage(tree, page, offset); btrfs_releasepage(page, GFP_NOFS); } @@ -2374,7 +2382,7 @@ unsigned long btrfs_force_ra(struct address_space *mapping, int btrfs_defrag_file(struct file *file) { struct inode *inode = fdentry(file)->d_inode; struct btrfs_root *root = BTRFS_I(inode)->root; - struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree; + struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree; struct page *page; unsigned long last_index; unsigned long ra_index = 0; @@ -2414,13 +2422,13 @@ int btrfs_defrag_file(struct file *file) { page_start = (u64)page->index << PAGE_CACHE_SHIFT; page_end = page_start + PAGE_CACHE_SIZE - 1; - lock_extent(em_tree, page_start, page_end, GFP_NOFS); + lock_extent(io_tree, page_start, page_end, GFP_NOFS); delalloc_start = page_start; existing_delalloc = - count_range_bits(&BTRFS_I(inode)->extent_tree, + count_range_bits(&BTRFS_I(inode)->io_tree, &delalloc_start, page_end, PAGE_CACHE_SIZE, EXTENT_DELALLOC); - set_extent_delalloc(em_tree, page_start, + set_extent_delalloc(io_tree, page_start, page_end, GFP_NOFS); spin_lock(&root->fs_info->delalloc_lock); @@ -2428,7 +2436,7 @@ int btrfs_defrag_file(struct file *file) { existing_delalloc; spin_unlock(&root->fs_info->delalloc_lock); - unlock_extent(em_tree, page_start, page_end, GFP_NOFS); + unlock_extent(io_tree, page_start, page_end, GFP_NOFS); set_page_dirty(page); unlock_page(page); page_cache_release(page); @@ -2842,9 +2850,10 @@ static int btrfs_symlink(struct inode *dir, struct dentry *dentry, inode->i_mapping->a_ops = &btrfs_aops; inode->i_fop = &btrfs_file_operations; inode->i_op = &btrfs_file_inode_operations; - extent_map_tree_init(&BTRFS_I(inode)->extent_tree, + extent_map_tree_init(&BTRFS_I(inode)->extent_tree, GFP_NOFS); + extent_io_tree_init(&BTRFS_I(inode)->io_tree, inode->i_mapping, GFP_NOFS); - BTRFS_I(inode)->extent_tree.ops = &btrfs_extent_map_ops; + BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops; } dir->i_sb->s_dirt = 1; btrfs_update_inode_block_group(trans, inode); @@ -2934,7 +2943,7 @@ static struct file_operations btrfs_dir_file_operations = { #endif }; -static struct extent_map_ops btrfs_extent_map_ops = { +static struct extent_io_ops btrfs_extent_io_ops = { .fill_delalloc = run_delalloc_range, .writepage_io_hook = btrfs_writepage_io_hook, .readpage_io_hook = btrfs_readpage_io_hook, -- cgit v1.2.1