Commit 5fbfb3f0 authored by Filipe Manana's avatar Filipe Manana Committed by David Sterba
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btrfs: use variables to store extent buffer and slot at overwrite_item() 



Instead of referring to path->nodes[0] and path->slots[0] multiple times,
which is verbose and confusing since we have an 'eb' and 'slot' variables
as well, introduce local variables 'dst_eb' to point to path->nodes[0] and
'dst_slot' to have path->slots[0], reducing verbosity and making it more
obvious about which extent buffer and slot we are referring to.

Signed-off-by: default avatarFilipe Manana <fdmanana@suse.com>
Reviewed-by: default avatarDavid Sterba <dsterba@suse.com>
Signed-off-by: default avatarDavid Sterba <dsterba@suse.com>
parent e48264e6

fs/btrfs/tree-log.c

+25 −22
Original line number Diff line number Diff line
@@ -401,6 +401,8 @@ static int overwrite_item(struct btrfs_trans_handle *trans, 
	int save_old_i_size = 0;

	unsigned long src_ptr;

	unsigned long dst_ptr;

	struct extent_buffer *dst_eb;

	int dst_slot;

	bool inode_item = key->type == BTRFS_INODE_ITEM_KEY;



	/*
@@ -420,10 +422,13 @@ static int overwrite_item(struct btrfs_trans_handle *trans, 
	if (ret < 0)

		return ret;



	dst_eb = path->nodes[0];

	dst_slot = path->slots[0];



	if (ret == 0) {

		char *src_copy;

		u32 dst_size = btrfs_item_size(path->nodes[0],

						  path->slots[0]);

		const u32 dst_size = btrfs_item_size(dst_eb, dst_slot);



		if (dst_size != item_size)

			goto insert;
@@ -438,8 +443,8 @@ static int overwrite_item(struct btrfs_trans_handle *trans, 
		}



		read_extent_buffer(eb, src_copy, src_ptr, item_size);

		dst_ptr = btrfs_item_ptr_offset(path->nodes[0], path->slots[0]);

		ret = memcmp_extent_buffer(path->nodes[0], src_copy, dst_ptr, item_size);

		dst_ptr = btrfs_item_ptr_offset(dst_eb, dst_slot);

		ret = memcmp_extent_buffer(dst_eb, src_copy, dst_ptr, item_size);



		kfree(src_copy);

		/*
@@ -462,9 +467,9 @@ static int overwrite_item(struct btrfs_trans_handle *trans, 
			u64 nbytes;

			u32 mode;



			item = btrfs_item_ptr(path->nodes[0], path->slots[0],

			item = btrfs_item_ptr(dst_eb, dst_slot,

					      struct btrfs_inode_item);

			nbytes = btrfs_inode_nbytes(path->nodes[0], item);

			nbytes = btrfs_inode_nbytes(dst_eb, item);

			item = btrfs_item_ptr(eb, slot,

					      struct btrfs_inode_item);

			btrfs_set_inode_nbytes(eb, item, nbytes);
@@ -506,11 +511,13 @@ static int overwrite_item(struct btrfs_trans_handle *trans, 
				      key, item_size);

	path->skip_release_on_error = 0;



	dst_eb = path->nodes[0];

	dst_slot = path->slots[0];



	/* make sure any existing item is the correct size */

	if (ret == -EEXIST || ret == -EOVERFLOW) {

		u32 found_size;

		found_size = btrfs_item_size(path->nodes[0],

						path->slots[0]);

		const u32 found_size = btrfs_item_size(dst_eb, dst_slot);



		if (found_size > item_size)

			btrfs_truncate_item(trans, path, item_size, 1);

		else if (found_size < item_size)
@@ -518,8 +525,7 @@ static int overwrite_item(struct btrfs_trans_handle *trans, 
	} else if (ret) {

		return ret;

	}

	dst_ptr = btrfs_item_ptr_offset(path->nodes[0],

					path->slots[0]);

	dst_ptr = btrfs_item_ptr_offset(dst_eb, dst_slot);



	/* don't overwrite an existing inode if the generation number

	 * was logged as zero.  This is done when the tree logging code
@@ -538,7 +544,6 @@ static int overwrite_item(struct btrfs_trans_handle *trans, 
		dst_item = (struct btrfs_inode_item *)dst_ptr;



		if (btrfs_inode_generation(eb, src_item) == 0) {

			struct extent_buffer *dst_eb = path->nodes[0];

			const u64 ino_size = btrfs_inode_size(eb, src_item);



			/*
@@ -556,30 +561,28 @@ static int overwrite_item(struct btrfs_trans_handle *trans, 
		}



		if (S_ISDIR(btrfs_inode_mode(eb, src_item)) &&

		    S_ISDIR(btrfs_inode_mode(path->nodes[0], dst_item))) {

		    S_ISDIR(btrfs_inode_mode(dst_eb, dst_item))) {

			save_old_i_size = 1;

			saved_i_size = btrfs_inode_size(path->nodes[0],

							dst_item);

			saved_i_size = btrfs_inode_size(dst_eb, dst_item);

		}

	}



	copy_extent_buffer(path->nodes[0], eb, dst_ptr,

			   src_ptr, item_size);

	copy_extent_buffer(dst_eb, eb, dst_ptr, src_ptr, item_size);



	if (save_old_i_size) {

		struct btrfs_inode_item *dst_item;



		dst_item = (struct btrfs_inode_item *)dst_ptr;

		btrfs_set_inode_size(path->nodes[0], dst_item, saved_i_size);

		btrfs_set_inode_size(dst_eb, dst_item, saved_i_size);

	}



	/* make sure the generation is filled in */

	if (key->type == BTRFS_INODE_ITEM_KEY) {

		struct btrfs_inode_item *dst_item;



		dst_item = (struct btrfs_inode_item *)dst_ptr;

		if (btrfs_inode_generation(path->nodes[0], dst_item) == 0) {

			btrfs_set_inode_generation(path->nodes[0], dst_item,

						   trans->transid);

		}

		if (btrfs_inode_generation(dst_eb, dst_item) == 0)

			btrfs_set_inode_generation(dst_eb, dst_item, trans->transid);

	}

no_copy:

	btrfs_release_path(path);