Re: [PATCH 08/25] ext4: support large block size in ext4_readdir()
From: Jan Kara <jack@suse.cz>
Date: 2025-11-03 08:27:57
Also in:
linux-fsdevel, linux-mm, lkml
On Sat 25-10-25 11:22:04, libaokun@huaweicloud.com wrote:
From: Baokun Li <redacted> In ext4_readdir(), page_cache_sync_readahead() is used to readahead mapped physical blocks. With LBS support, this can lead to a negative right shift. To fix this, the page index is now calculated by first converting the physical block number (pblk) to a file position (pos) before converting it to a page index. Also, the correct number of pages to readahead is now passed. Signed-off-by: Baokun Li <redacted> Reviewed-by: Zhang Yi <yi.zhang@huawei.com>
Looks good. Feel free to add: Reviewed-by: Jan Kara <jack@suse.cz> Honza
quoted hunk ↗ jump to hunk
diff --git a/fs/ext4/dir.c b/fs/ext4/dir.c index d4164c507a90..256fe2c1d4c1 100644 --- a/fs/ext4/dir.c +++ b/fs/ext4/dir.c@@ -192,13 +192,13 @@ static int ext4_readdir(struct file *file, struct dir_context *ctx) continue; } if (err > 0) { - pgoff_t index = map.m_pblk >> - (PAGE_SHIFT - inode->i_blkbits); + pgoff_t index = map.m_pblk << inode->i_blkbits >> + PAGE_SHIFT; if (!ra_has_index(&file->f_ra, index)) page_cache_sync_readahead( sb->s_bdev->bd_mapping, - &file->f_ra, file, - index, 1); + &file->f_ra, file, index, + 1 << EXT4_SB(sb)->s_min_folio_order); file->f_ra.prev_pos = (loff_t)index << PAGE_SHIFT; bh = ext4_bread(NULL, inode, map.m_lblk, 0); if (IS_ERR(bh)) {-- 2.46.1
-- Jan Kara [off-list ref] SUSE Labs, CR