From 7ed6cbe0f8caa6ee38a2dc8f1b925acb904cc01f Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Thu, 9 Jan 2025 09:31:02 +0100 Subject: fs: add STATX_DIO_READ_ALIGN Add a separate dio read align field, as many out of place write file systems can easily do reads aligned to the device sector size, but require bigger alignment for writes. This is usually papered over by falling back to buffered I/O for smaller writes and doing read-modify-write cycles, but performance for this sucks, so applications benefit from knowing the actual write alignment. Signed-off-by: Christoph Hellwig Link: https://lore.kernel.org/r/20250109083109.1441561-3-hch@lst.de Reviewed-by: John Garry Reviewed-by: Jan Kara Reviewed-by: Darrick J. Wong Signed-off-by: Christian Brauner --- include/linux/stat.h | 1 + 1 file changed, 1 insertion(+) (limited to 'include/linux/stat.h') diff --git a/include/linux/stat.h b/include/linux/stat.h index 3d900c86981c..9d8382e23a9c 100644 --- a/include/linux/stat.h +++ b/include/linux/stat.h @@ -52,6 +52,7 @@ struct kstat { u64 mnt_id; u32 dio_mem_align; u32 dio_offset_align; + u32 dio_read_offset_align; u64 change_cookie; u64 subvol; u32 atomic_write_unit_min; -- cgit v1.2.3 From 27560b371ab82c1894d048aef0d113acb093f67f Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Wed, 29 Jan 2025 07:37:57 +0100 Subject: fs: pack struct kstat better Move the change_cookie and subvol up to avoid two 4 byte holes. Signed-off-by: Christoph Hellwig Signed-off-by: Linus Torvalds --- include/linux/stat.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'include/linux/stat.h') diff --git a/include/linux/stat.h b/include/linux/stat.h index 9d8382e23a9c..be7496a6a0dd 100644 --- a/include/linux/stat.h +++ b/include/linux/stat.h @@ -50,11 +50,11 @@ struct kstat { struct timespec64 btime; /* File creation time */ u64 blocks; u64 mnt_id; + u64 change_cookie; + u64 subvol; u32 dio_mem_align; u32 dio_offset_align; u32 dio_read_offset_align; - u64 change_cookie; - u64 subvol; u32 atomic_write_unit_min; u32 atomic_write_unit_max; u32 atomic_write_segments_max; -- cgit v1.2.3