Commit bff6235d authored by Baokun Li's avatar Baokun Li Committed by Theodore Ts'o
Browse files

ext4: support large block size in ext4_block_write_begin() 



Use the EXT4_PG_TO_LBLK() macro to convert folio indexes to blocks to avoid
negative left shifts after supporting blocksize greater than PAGE_SIZE.

Signed-off-by: default avatarBaokun Li <libaokun1@huawei.com>
Reviewed-by: default avatarZhang Yi <yi.zhang@huawei.com>
Reviewed-by: default avatarJan Kara <jack@suse.cz>
Reviewed-by: default avatarOjaswin Mujoo <ojaswin@linux.ibm.com>
Message-ID: <20251121090654.631996-18-libaokun@huaweicloud.com>
Signed-off-by: default avatarTheodore Ts'o <tytso@mit.edu>
parent a6d73242

fs/ext4/inode.c

+3 −4
Original line number Diff line number Diff line
@@ -1170,8 +1170,7 @@ int ext4_block_write_begin(handle_t *handle, struct folio *folio, 
	unsigned block_start, block_end;

	sector_t block;

	int err = 0;

	unsigned blocksize = inode->i_sb->s_blocksize;

	unsigned bbits;

	unsigned int blocksize = i_blocksize(inode);

	struct buffer_head *bh, *head, *wait[2];

	int nr_wait = 0;

	int i;
@@ -1180,12 +1179,12 @@ int ext4_block_write_begin(handle_t *handle, struct folio *folio, 
	BUG_ON(!folio_test_locked(folio));

	BUG_ON(to > folio_size(folio));

	BUG_ON(from > to);

	WARN_ON_ONCE(blocksize > folio_size(folio));



	head = folio_buffers(folio);

	if (!head)

		head = create_empty_buffers(folio, blocksize, 0);

	bbits = ilog2(blocksize);

	block = (sector_t)folio->index << (PAGE_SHIFT - bbits);

	block = EXT4_PG_TO_LBLK(inode, folio->index);



	for (bh = head, block_start = 0; bh != head || !block_start;

	    block++, block_start = block_end, bh = bh->b_this_page) {