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4edafa81a1
jbd2_inode fields are updated under journal->j_list_lock, but some paths read them without holding the lock (e.g. fast commit helpers and ordered truncate helpers). READ_ONCE() alone is not sufficient for the dirty range fields when they are stored as loff_t because 32-bit platforms can observe torn loads. Store the dirty range in PAGE_SIZE units as pgoff_t instead. Represent the dirty range end as an exclusive end page. This avoids a special sentinel value and keeps MAX_LFS_FILESIZE on 32-bit representable. Publish a new dirty range by updating end_page before start_page, and treat start_page >= end_page as empty in the accessor for robustness. Use READ_ONCE() on the read side and WRITE_ONCE() on the write side for the dirty range and i_flags to match the existing lockless access pattern. Suggested-by: Jan Kara <jack@suse.cz> Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Li Chen <me@linux.beauty> Link: https://patch.msgid.link/20260306085643.465275-5-me@linux.beauty Signed-off-by: Theodore Ts'o <tytso@mit.edu>