f2fs: fix to cover __allocate_new_section() with curseg_lock

chaseyu · Jaegeuk Kim · commit 823d13e12b6c · 2021-03-26T10:27:46.000-07:00
In order to avoid race with f2fs_do_replace_block(). Fixes: f5a53ed ("f2fs: support aligned pinned file") Signed-off-by: Chao Yu <yuchao0@huawei.com> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c
@@ -2945,19 +2945,23 @@ static void __allocate_new_section(struct f2fs_sb_info *sbi, int type)
 
 void f2fs_allocate_new_section(struct f2fs_sb_info *sbi, int type)
 {
+	down_read(&SM_I(sbi)->curseg_lock);
 	down_write(&SIT_I(sbi)->sentry_lock);
 	__allocate_new_section(sbi, type);
 	up_write(&SIT_I(sbi)->sentry_lock);
+	up_read(&SM_I(sbi)->curseg_lock);
 }
 
 void f2fs_allocate_new_segments(struct f2fs_sb_info *sbi)
 {
 	int i;
 
+	down_read(&SM_I(sbi)->curseg_lock);
 	down_write(&SIT_I(sbi)->sentry_lock);
 	for (i = CURSEG_HOT_DATA; i <= CURSEG_COLD_DATA; i++)
 		__allocate_new_segment(sbi, i, false);
 	up_write(&SIT_I(sbi)->sentry_lock);
+	up_read(&SM_I(sbi)->curseg_lock);
 }
 
 static const struct segment_allocation default_salloc_ops = {

Original file line number	Diff line number	Diff line change
`@@ -2945,19 +2945,23 @@ static void __allocate_new_section(struct f2fs_sb_info *sbi, int type)`
`2945`	`2945`
`2946`	`2946`	`void f2fs_allocate_new_section(struct f2fs_sb_info *sbi, int type)`
`2947`	`2947`	`{`
	`2948`	`+ down_read(&SM_I(sbi)->curseg_lock);`
`2948`	`2949`	`down_write(&SIT_I(sbi)->sentry_lock);`
`2949`	`2950`	`__allocate_new_section(sbi, type);`
`2950`	`2951`	`up_write(&SIT_I(sbi)->sentry_lock);`
	`2952`	`+ up_read(&SM_I(sbi)->curseg_lock);`
`2951`	`2953`	`}`
`2952`	`2954`
`2953`	`2955`	`void f2fs_allocate_new_segments(struct f2fs_sb_info *sbi)`
`2954`	`2956`	`{`
`2955`	`2957`	`int i;`
`2956`	`2958`
	`2959`	`+ down_read(&SM_I(sbi)->curseg_lock);`
`2957`	`2960`	`down_write(&SIT_I(sbi)->sentry_lock);`
`2958`	`2961`	`for (i = CURSEG_HOT_DATA; i <= CURSEG_COLD_DATA; i++)`
`2959`	`2962`	`__allocate_new_segment(sbi, i, false);`
`2960`	`2963`	`up_write(&SIT_I(sbi)->sentry_lock);`
	`2964`	`+ up_read(&SM_I(sbi)->curseg_lock);`
`2961`	`2965`	`}`
`2962`	`2966`
`2963`	`2967`	`static const struct segment_allocation default_salloc_ops = {`