[PATCH 1/2 v5] exfat: write multiple sectors at once

From: Tetsuhiro Kohada
Date: Tue Jun 23 2020 - 02:22:29 EST


Write multiple sectors at once when updating dir-entries.
Add exfat_update_bhs() for that. It wait for write completion once
instead of sector by sector.
It's only effective if sync enabled.

Signed-off-by: Tetsuhiro Kohada <kohada.t2@xxxxxxxxx>
---
Changes in v2:
- Split into 'write multiple sectors at once'
and 'add error check when updating dir-entries'
Changes in v3
- Rebase to latest exfat-dev
Changes in v4
- Use if/else instead of conditional operator
Changes in v5
- Remove Reviewed-by tag

fs/exfat/dir.c | 15 +++++++++------
fs/exfat/exfat_fs.h | 1 +
fs/exfat/misc.c | 19 +++++++++++++++++++
3 files changed, 29 insertions(+), 6 deletions(-)

diff --git a/fs/exfat/dir.c b/fs/exfat/dir.c
index 02acbb6ddf02..7c2e29632634 100644
--- a/fs/exfat/dir.c
+++ b/fs/exfat/dir.c
@@ -606,13 +606,16 @@ void exfat_update_dir_chksum_with_entry_set(struct exfat_entry_set_cache *es)

void exfat_free_dentry_set(struct exfat_entry_set_cache *es, int sync)
{
- int i;
+ int i, err = 0;

- for (i = 0; i < es->num_bh; i++) {
- if (es->modified)
- exfat_update_bh(es->bh[i], sync);
- brelse(es->bh[i]);
- }
+ if (es->modified)
+ err = exfat_update_bhs(es->bh, es->num_bh, sync);
+
+ for (i = 0; i < es->num_bh; i++)
+ if (err)
+ bforget(es->bh[i]);
+ else
+ brelse(es->bh[i]);
kfree(es);
}

diff --git a/fs/exfat/exfat_fs.h b/fs/exfat/exfat_fs.h
index 84664024e51e..cbb00ee97183 100644
--- a/fs/exfat/exfat_fs.h
+++ b/fs/exfat/exfat_fs.h
@@ -512,6 +512,7 @@ void exfat_set_entry_time(struct exfat_sb_info *sbi, struct timespec64 *ts,
u16 exfat_calc_chksum16(void *data, int len, u16 chksum, int type);
u32 exfat_calc_chksum32(void *data, int len, u32 chksum, int type);
void exfat_update_bh(struct buffer_head *bh, int sync);
+int exfat_update_bhs(struct buffer_head **bhs, int nr_bhs, int sync);
void exfat_chain_set(struct exfat_chain *ec, unsigned int dir,
unsigned int size, unsigned char flags);
void exfat_chain_dup(struct exfat_chain *dup, struct exfat_chain *ec);
diff --git a/fs/exfat/misc.c b/fs/exfat/misc.c
index 8a3dde59052b..564718747fb2 100644
--- a/fs/exfat/misc.c
+++ b/fs/exfat/misc.c
@@ -172,6 +172,25 @@ void exfat_update_bh(struct buffer_head *bh, int sync)
sync_dirty_buffer(bh);
}

+int exfat_update_bhs(struct buffer_head **bhs, int nr_bhs, int sync)
+{
+ int i, err = 0;
+
+ for (i = 0; i < nr_bhs; i++) {
+ set_buffer_uptodate(bhs[i]);
+ mark_buffer_dirty(bhs[i]);
+ if (sync)
+ write_dirty_buffer(bhs[i], 0);
+ }
+
+ for (i = 0; i < nr_bhs && sync; i++) {
+ wait_on_buffer(bhs[i]);
+ if (!buffer_uptodate(bhs[i]))
+ err = -EIO;
+ }
+ return err;
+}
+
void exfat_chain_set(struct exfat_chain *ec, unsigned int dir,
unsigned int size, unsigned char flags)
{
--
2.25.1