Commit 07c440e8 authored by Zhang Yi's avatar Zhang Yi Committed by Theodore Ts'o
Browse files

ext4: pass out extent seq counter when mapping blocks 



When creating or querying mapping blocks using the ext4_map_blocks() and
ext4_map_{query|create}_blocks() helpers, also pass out the extent
sequence number of the block mapping info through the ext4_map_blocks
structure. This sequence number can later serve as a valid cookie within
iomap infrastructure and the move extents procedure.

Signed-off-by: default avatarZhang Yi <yi.zhang@huawei.com>
Reviewed-by: default avatarJan Kara <jack@suse.cz>
Message-ID: <20251013015128.499308-5-yi.zhang@huaweicloud.com>
Signed-off-by: default avatarTheodore Ts'o <tytso@mit.edu>
parent 7da5565c

fs/ext4/ext4.h

+1 −0
Original line number Diff line number Diff line
@@ -260,6 +260,7 @@ struct ext4_map_blocks { 
	ext4_lblk_t m_lblk;

	unsigned int m_len;

	unsigned int m_flags;

	u64 m_seq;

};



/*

fs/ext4/inode.c

+16 −8
Original line number Diff line number Diff line
@@ -550,10 +550,13 @@ static int ext4_map_query_blocks(handle_t *handle, struct inode *inode, 
		retval = ext4_ext_map_blocks(handle, inode, map, flags);

	else

		retval = ext4_ind_map_blocks(handle, inode, map, flags);



	if (retval <= 0)

	if (retval < 0)

		return retval;



	/* A hole? */

	if (retval == 0)

		goto out;



	if (unlikely(retval != map->m_len)) {

		ext4_warning(inode->i_sb,

			     "ES len assertion failed for inode "
@@ -573,12 +576,14 @@ static int ext4_map_query_blocks(handle_t *handle, struct inode *inode, 
				EXTENT_STATUS_UNWRITTEN : EXTENT_STATUS_WRITTEN;

		ext4_es_insert_extent(inode, map->m_lblk, map->m_len,

				      map->m_pblk, status, false);

		return retval;

	}



	return ext4_map_query_blocks_next_in_leaf(handle, inode, map,

	} else {

		retval = ext4_map_query_blocks_next_in_leaf(handle, inode, map,

							    orig_mlen);

	}

out:

	map->m_seq = READ_ONCE(EXT4_I(inode)->i_es_seq);

	return retval;

}



static int ext4_map_create_blocks(handle_t *handle, struct inode *inode,

				  struct ext4_map_blocks *map, int flags)
@@ -649,7 +654,7 @@ static int ext4_map_create_blocks(handle_t *handle, struct inode *inode, 
	 * extent status tree.

	 */

	if (flags & EXT4_GET_BLOCKS_PRE_IO &&

	    ext4_es_lookup_extent(inode, map->m_lblk, NULL, &es, NULL)) {

	    ext4_es_lookup_extent(inode, map->m_lblk, NULL, &es, &map->m_seq)) {

		if (ext4_es_is_written(&es))

			return retval;

	}
@@ -658,6 +663,7 @@ static int ext4_map_create_blocks(handle_t *handle, struct inode *inode, 
			EXTENT_STATUS_UNWRITTEN : EXTENT_STATUS_WRITTEN;

	ext4_es_insert_extent(inode, map->m_lblk, map->m_len, map->m_pblk,

			      status, flags & EXT4_GET_BLOCKS_DELALLOC_RESERVE);

	map->m_seq = READ_ONCE(EXT4_I(inode)->i_es_seq);



	return retval;

}
@@ -723,7 +729,7 @@ int ext4_map_blocks(handle_t *handle, struct inode *inode, 
		ext4_check_map_extents_env(inode);



	/* Lookup extent status tree firstly */

	if (ext4_es_lookup_extent(inode, map->m_lblk, NULL, &es, NULL)) {

	if (ext4_es_lookup_extent(inode, map->m_lblk, NULL, &es, &map->m_seq)) {

		if (ext4_es_is_written(&es) || ext4_es_is_unwritten(&es)) {

			map->m_pblk = ext4_es_pblock(&es) +

					map->m_lblk - es.es_lblk;
@@ -1979,6 +1985,8 @@ static int ext4_da_map_blocks(struct inode *inode, struct ext4_map_blocks *map) 


	map->m_flags |= EXT4_MAP_DELAYED;

	retval = ext4_insert_delayed_blocks(inode, map->m_lblk, map->m_len);

	if (!retval)

		map->m_seq = READ_ONCE(EXT4_I(inode)->i_es_seq);

	up_write(&EXT4_I(inode)->i_data_sem);



	return retval;