Commit 07157aac authored by Chris Mason's avatar Chris Mason Committed by David Woodhouse
Browse files

Btrfs: Add file data csums back in via hooks in the extent map code 



Signed-off-by: default avatarChris Mason <chris.mason@oracle.com>
parent 95e05289

fs/btrfs/extent_map.c

+84 −10
Original line number Diff line number Diff line
@@ -57,7 +57,7 @@ void extent_map_tree_init(struct extent_map_tree *tree, 
{

	tree->map.rb_node = NULL;

	tree->state.rb_node = NULL;

	tree->fill_delalloc = NULL;

	tree->ops = NULL;

	rwlock_init(&tree->lock);

	tree->mapping = mapping;

}
@@ -93,6 +93,7 @@ struct extent_state *alloc_extent_state(gfp_t mask) 
		return state;

	state->state = 0;

	state->in_tree = 0;

	state->private = 0;

	atomic_set(&state->refs, 1);

	init_waitqueue_head(&state->wq);

	return state;
@@ -1034,6 +1035,61 @@ int unlock_range(struct extent_map_tree *tree, u64 start, u64 end) 
}

EXPORT_SYMBOL(unlock_range);



int set_state_private(struct extent_map_tree *tree, u64 start, u64 private)

{

	struct rb_node *node;

	struct extent_state *state;

	int ret = 0;



	write_lock_irq(&tree->lock);

	/*

	 * this search will find all the extents that end after

	 * our range starts.

	 */

	node = tree_search(&tree->state, start);

	if (!node || IS_ERR(node)) {

		ret = -ENOENT;

		goto out;

	}

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

	if (state->start != start) {

		ret = -ENOENT;

		goto out;

	}

	state->private = private;

out:

	write_unlock_irq(&tree->lock);

	return ret;



}



int get_state_private(struct extent_map_tree *tree, u64 start, u64 *private)

{

	struct rb_node *node;

	struct extent_state *state;

	int ret = 0;



	read_lock_irq(&tree->lock);

	/*

	 * this search will find all the extents that end after

	 * our range starts.

	 */

	node = tree_search(&tree->state, start);

	if (!node || IS_ERR(node)) {

		ret = -ENOENT;

		goto out;

	}

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

	if (state->start != start) {

		ret = -ENOENT;

		goto out;

	}

	*private = state->private;

out:

	read_unlock_irq(&tree->lock);

	return ret;

}



/*

 * searches a range in the state tree for a given mask.

 * If 'filled' == 1, this returns 1 only if ever extent in the tree
@@ -1185,12 +1241,13 @@ static int end_bio_extent_writepage(struct bio *bio, 
static int end_bio_extent_readpage(struct bio *bio,

				   unsigned int bytes_done, int err)

{

	const int uptodate = test_bit(BIO_UPTODATE, &bio->bi_flags);

	int uptodate = test_bit(BIO_UPTODATE, &bio->bi_flags);

	struct bio_vec *bvec = bio->bi_io_vec + bio->bi_vcnt - 1;

	struct extent_map_tree *tree = bio->bi_private;

	u64 start;

	u64 end;

	int whole_page;

	int ret;



	if (bio->bi_size)

		return 1;
@@ -1208,6 +1265,11 @@ static int end_bio_extent_readpage(struct bio *bio, 
		if (--bvec >= bio->bi_io_vec)

			prefetchw(&bvec->bv_page->flags);



		if (uptodate && tree->ops && tree->ops->readpage_end_io_hook) {

			ret = tree->ops->readpage_end_io_hook(page, start, end);

			if (ret)

				uptodate = 0;

		}

		if (uptodate) {

			set_extent_uptodate(tree, start, end, GFP_ATOMIC);

			if (whole_page)
@@ -1388,9 +1450,16 @@ int extent_read_full_page(struct extent_map_tree *tree, struct page *page, 
			continue;

		}



		ret = 0;

		if (tree->ops && tree->ops->readpage_io_hook) {

			ret = tree->ops->readpage_io_hook(page, cur,

							  cur + iosize - 1);

		}

		if (!ret) {

			ret = submit_extent_page(READ, tree, page,

					 sector, iosize, page_offset, bdev,

					 end_bio_extent_readpage);

						 sector, iosize, page_offset,

						 bdev, end_bio_extent_readpage);

		}

		if (ret)

			SetPageError(page);

		cur = cur + iosize;
@@ -1462,7 +1531,7 @@ int extent_write_full_page(struct extent_map_tree *tree, struct page *page, 
					       &delalloc_end,

					       128 * 1024 * 1024);

	if (nr_delalloc) {

		tree->fill_delalloc(inode, start, delalloc_end);

		tree->ops->fill_delalloc(inode, start, delalloc_end);

		if (delalloc_end >= page_end + 1) {

			clear_extent_bit(tree, page_end + 1, delalloc_end,

					 EXTENT_LOCKED | EXTENT_DELALLOC,
@@ -1528,12 +1597,17 @@ int extent_write_full_page(struct extent_map_tree *tree, struct page *page, 
			continue;

		}

		clear_extent_dirty(tree, cur, cur + iosize - 1, GFP_NOFS);

		ret = tree->ops->writepage_io_hook(page, cur, cur + iosize - 1);

		if (ret)

			SetPageError(page);

		else {

			set_range_writeback(tree, cur, cur + iosize - 1);

		ret = submit_extent_page(WRITE, tree, page,

					 sector, iosize, page_offset, bdev,

			ret = submit_extent_page(WRITE, tree, page, sector,

						 iosize, page_offset, bdev,

						 end_bio_extent_writepage);

			if (ret)

				SetPageError(page);

		}

		cur = cur + iosize;

		page_offset += iosize;

		nr++;

fs/btrfs/extent_map.h

+14 −1
Original line number Diff line number Diff line
@@ -6,12 +6,19 @@ 
#define EXTENT_MAP_INLINE (u64)-2

#define EXTENT_MAP_DELALLOC (u64)-1



struct extent_map_ops {

	int (*fill_delalloc)(struct inode *inode, u64 start, u64 end);

	int (*writepage_io_hook)(struct page *page, u64 start, u64 end);

	int (*readpage_io_hook)(struct page *page, u64 start, u64 end);

	int (*readpage_end_io_hook)(struct page *page, u64 start, u64 end);

};



struct extent_map_tree {

	struct rb_root map;

	struct rb_root state;

	struct address_space *mapping;

	rwlock_t lock;

	int (*fill_delalloc)(struct inode *inode, u64 start, u64 end);

	struct extent_map_ops *ops;

};



/* note, this must start with the same fields as fs/extent_map.c:tree_entry */
@@ -36,6 +43,10 @@ struct extent_state { 
	wait_queue_head_t wq;

	atomic_t refs;

	unsigned long state;



	/* for use by the FS */

	u64 private;



	struct list_head list;

};
@@ -89,4 +100,6 @@ 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);

int set_state_private(struct extent_map_tree *tree, u64 start, u64 private);

int get_state_private(struct extent_map_tree *tree, u64 start, u64 *private);

#endif

fs/btrfs/inode.c

+95 −3
Original line number Diff line number Diff line
@@ -52,6 +52,7 @@ 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 kmem_cache *btrfs_inode_cachep;

struct kmem_cache *btrfs_trans_handle_cachep;
@@ -103,6 +104,90 @@ static int run_delalloc_range(struct inode *inode, u64 start, u64 end) 
	return ret;

}



int btrfs_writepage_io_hook(struct page *page, u64 start, u64 end)

{

	struct inode *inode = page->mapping->host;

	struct btrfs_root *root = BTRFS_I(inode)->root;

	struct btrfs_trans_handle *trans;

	char *kaddr;

	int ret;

	u64 page_start = page->index << PAGE_CACHE_SHIFT;

	size_t offset = start - page_start;



	mutex_lock(&root->fs_info->fs_mutex);

	trans = btrfs_start_transaction(root, 1);

	btrfs_set_trans_block_group(trans, inode);

	kaddr = kmap(page);

	btrfs_csum_file_block(trans, root, inode->i_ino,

			      start, kaddr + offset, end - start + 1);

	kunmap(page);

	ret = btrfs_end_transaction(trans, root);

	BUG_ON(ret);

	mutex_unlock(&root->fs_info->fs_mutex);

	return ret;

}



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 btrfs_csum_item *item;

	struct btrfs_path *path = NULL;

	u64 private;



	mutex_lock(&root->fs_info->fs_mutex);

	path = btrfs_alloc_path();

	item = btrfs_lookup_csum(NULL, root, path, inode->i_ino, start, 0);

	if (IS_ERR(item)) {

		ret = PTR_ERR(item);

		/* a csum that isn't present is a preallocated region. */

		if (ret == -ENOENT || ret == -EFBIG)

			ret = 0;

		private = 0;

		goto out;

	}

	memcpy((char *)&private, &item->csum, BTRFS_CRC32_SIZE);

	set_state_private(em_tree, start, private);

out:

	if (path)

		btrfs_free_path(path);

	mutex_unlock(&root->fs_info->fs_mutex);

	return ret;

}



int btrfs_readpage_end_io_hook(struct page *page, u64 start, u64 end)

{

	char csum[BTRFS_CRC32_SIZE];

	size_t offset = start - (page->index << PAGE_CACHE_SHIFT);

	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;

	char *kaddr;

	u64 private;

	int ret;



	ret = get_state_private(em_tree, start, &private);

	kaddr = kmap_atomic(page, KM_IRQ0);

	if (ret) {

		goto zeroit;

	}

	ret = btrfs_csum_data(root, kaddr + offset, end - start + 1, csum);

	BUG_ON(ret);

	if (memcmp(csum, &private, BTRFS_CRC32_SIZE)) {

		goto zeroit;

	}

	kunmap_atomic(kaddr, KM_IRQ0);

	return 0;



zeroit:

	printk("btrfs csum failed ino %lu off %llu\n",

	       page->mapping->host->i_ino, (unsigned long long)start);

	memset(kaddr + offset, 1, end - start + 1); flush_dcache_page(page);

	kunmap_atomic(kaddr, KM_IRQ0);

	return 0;

}



void btrfs_read_locked_inode(struct inode *inode)

{
@@ -155,7 +240,7 @@ 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.fill_delalloc = run_delalloc_range;

		BTRFS_I(inode)->extent_tree.ops = &btrfs_extent_map_ops;

		inode->i_fop = &btrfs_file_operations;

		inode->i_op = &btrfs_file_inode_operations;

		break;
@@ -1148,7 +1233,7 @@ static int btrfs_create(struct inode *dir, struct dentry *dentry, 
		inode->i_op = &btrfs_file_inode_operations;

		extent_map_tree_init(&BTRFS_I(inode)->extent_tree,

				     inode->i_mapping, GFP_NOFS);

		BTRFS_I(inode)->extent_tree.fill_delalloc = run_delalloc_range;

		BTRFS_I(inode)->extent_tree.ops = &btrfs_extent_map_ops;

	}

	dir->i_sb->s_dirt = 1;

	btrfs_update_inode_block_group(trans, inode);
@@ -2286,7 +2371,7 @@ static int btrfs_symlink(struct inode *dir, struct dentry *dentry, 
		inode->i_op = &btrfs_file_inode_operations;

		extent_map_tree_init(&BTRFS_I(inode)->extent_tree,

				     inode->i_mapping, GFP_NOFS);

		BTRFS_I(inode)->extent_tree.fill_delalloc = run_delalloc_range;

		BTRFS_I(inode)->extent_tree.ops = &btrfs_extent_map_ops;

	}

	dir->i_sb->s_dirt = 1;

	btrfs_update_inode_block_group(trans, inode);
@@ -2362,6 +2447,13 @@ static struct file_operations btrfs_dir_file_operations = { 
#endif

};



static struct extent_map_ops btrfs_extent_map_ops = {

	.fill_delalloc = run_delalloc_range,

	.writepage_io_hook = btrfs_writepage_io_hook,

	.readpage_io_hook = btrfs_readpage_io_hook,

	.readpage_end_io_hook = btrfs_readpage_end_io_hook,

};



static struct address_space_operations btrfs_aops = {

	.readpage	= btrfs_readpage,

	.writepage	= btrfs_writepage,