From 46e269016e966c5d4c38a3fc8ebe7c65d4609ba2 Mon Sep 17 00:00:00 2001 From: Zhengxu Zhang Date: Thu, 12 Jun 2025 09:14:21 +0800 Subject: [PATCH] FROMGIT: exfat: fdatasync flag should be same like generic_write_sync() Test: androbench by default setting, use 64GB sdcard. the random write speed: without this patch 3.5MB/s with this patch 7MB/s After patch "11a347fb6cef", the random write speed decreased significantly.the .write_iter() interface had been modified, and check the differences with generic_file_write_iter(), when calling generic_write_sync() and exfat_file_write_iter() to call vfs_fsync_range(), the fdatasync flag is wrong, and make not use the fdatasync mode, and make random write speed decreased. So use generic_write_sync() instead of vfs_fsync_range(). Fixes: 11a347fb6cef ("exfat: change to get file size from DataLength") Bug: 427084532 (cherry picked from commit 309914e6602c9e17ff84b20db8c4f1da0d6a2a36 https://git.kernel.org/pub/scm/linux/kernel/git/linkinjeon/exfat.git dev) Link: https://lore.kernel.org/all/20250619013331.664521-1-zhengxu.zhang@unisoc.com/ Change-Id: I68319a27cabedd9d4a7fa35948affd8c27d72160 Signed-off-by: Zhengxu Zhang Acked-by: Yuezhang Mo Signed-off-by: Namjae Jeon --- fs/exfat/file.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) diff --git a/fs/exfat/file.c b/fs/exfat/file.c index efd24e29f119..272208708ffc 100644 --- a/fs/exfat/file.c +++ b/fs/exfat/file.c @@ -610,9 +610,8 @@ static ssize_t exfat_file_write_iter(struct kiocb *iocb, struct iov_iter *iter) if (pos > valid_size) pos = valid_size; - if (iocb_is_dsync(iocb) && iocb->ki_pos > pos) { - ssize_t err = vfs_fsync_range(file, pos, iocb->ki_pos - 1, - iocb->ki_flags & IOCB_SYNC); + if (iocb->ki_pos > pos) { + ssize_t err = generic_write_sync(iocb, iocb->ki_pos - pos); if (err < 0) return err; }