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From: Zhiguo Niu <zhiguo.niu@unisoc.com>
To: <jaegeuk@kernel.org>, <chao@kernel.org>
CC: <linux-f2fs-devel@lists.sourceforge.net>, <linux-kernel@vger.kernel.org>,
        <niuzhiguo84@gmail.com>, <zhiguo.niu@unisoc.com>, <ke.wang@unisoc.com>,
        <hongyu.jin@unisoc.com>
Subject: [PATCH v2 4/4] f2fs: stop checkpoint when get a out-of-bounds segment
Date: Wed, 7 Feb 2024 10:01:04 +0800
Message-ID: <1707271264-5551-5-git-send-email-zhiguo.niu@unisoc.com>
In-Reply-To: <1707271264-5551-1-git-send-email-zhiguo.niu@unisoc.com>
References: <1707271264-5551-1-git-send-email-zhiguo.niu@unisoc.com>
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There is low probability that an out-of-bounds segment will be got
on a small-capacity device. In order to prevent subsequent write requests
allocating block address from this invalid segment, which may cause
unexpected issue, stop checkpoint should be performed.

Also introduce a new stop cp reason:  STOP_CP_REASON_OUTOF_RAGNE.

Signed-off-by: Zhiguo Niu <zhiguo.niu@unisoc.com>
---
 fs/f2fs/segment.c       | 12 ++++++++++--
 include/linux/f2fs_fs.h |  1 +
 2 files changed, 11 insertions(+), 2 deletions(-)

diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c
index 6772ad4..6fe2baf 100644
--- a/fs/f2fs/segment.c
+++ b/fs/f2fs/segment.c
@@ -2666,7 +2666,11 @@ static void get_new_segment(struct f2fs_sb_info *sbi,
 		if (dir == ALLOC_RIGHT) {
 			secno = find_first_zero_bit(free_i->free_secmap,
 							MAIN_SECS(sbi));
-			f2fs_bug_on(sbi, secno >= MAIN_SECS(sbi));
+			if (secno >= MAIN_SECS(sbi)) {
+				f2fs_stop_checkpoint(sbi, false,
+						STOP_CP_REASON_OUTOF_RAGNE);
+				f2fs_bug_on(sbi, 1);
+			}
 		} else {
 			go_left = 1;
 			left_start = hint - 1;
@@ -2682,7 +2686,11 @@ static void get_new_segment(struct f2fs_sb_info *sbi,
 		}
 		left_start = find_first_zero_bit(free_i->free_secmap,
 							MAIN_SECS(sbi));
-		f2fs_bug_on(sbi, left_start >= MAIN_SECS(sbi));
+		if (left_start >= MAIN_SECS(sbi)) {
+			f2fs_stop_checkpoint(sbi, false,
+					STOP_CP_REASON_OUTOF_RAGNE);
+			f2fs_bug_on(sbi, 1);
+		}
 		break;
 	}
 	secno = left_start;
diff --git a/include/linux/f2fs_fs.h b/include/linux/f2fs_fs.h
index 053137a0..72c6782 100644
--- a/include/linux/f2fs_fs.h
+++ b/include/linux/f2fs_fs.h
@@ -81,6 +81,7 @@ enum stop_cp_reason {
 	STOP_CP_REASON_CORRUPTED_SUMMARY,
 	STOP_CP_REASON_UPDATE_INODE,
 	STOP_CP_REASON_FLUSH_FAIL,
+	STOP_CP_REASON_OUTOF_RAGNE,
 	STOP_CP_REASON_MAX,
 };
 
-- 
1.9.1