linux-kernel - [f2fs-dev] [PATCH V2] f2fs: The GC triggered by ioctl also needs to mark the segno as victim

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-Id: <20241204033113.4133027-1-yangyongpeng1@oppo.com>
Date: Wed,  4 Dec 2024 11:31:13 +0800
From: Yongpeng Yang <yangyongpeng1@...o.com>
To: Jaegeuk Kim <jaegeuk@...nel.org>,
	Chao Yu <chao@...nel.org>
Cc: linux-f2fs-devel@...ts.sourceforge.net,
	linux-kernel@...r.kernel.org,
	Yongpeng Yang <yangyongpeng1@...o.com>
Subject: [f2fs-dev] [PATCH V2] f2fs: The GC triggered by ioctl also needs to mark the segno as victim

In SSR mode, the segment selected for allocation might be the same as
the target segment of the GC triggered by ioctl, resulting in the GC
moving the CURSEG_I(sbi, type)->segno.
Thread A				Thread B or Thread A
- f2fs_ioc_gc_range
 - __f2fs_ioc_gc_range(.victim_segno=segno#N)
  - f2fs_gc
   - __get_victim
    - f2fs_get_victim
    : segno#N is valid, return segno#N as source segment of GC
					- f2fs_allocate_data_block
						- need_new_seg
						- get_ssr_segment
						- f2fs_get_victim
						: get segno #N as destination segment
						- change_curseg

Fixes: e066b83c9b40 ("f2fs: add ioctl to flush data from faster device to cold area")
Signed-off-by: Yongpeng Yang <yangyongpeng1@...o.com>
---
V2: Include an explanation of concurrent scenarios.
---
 fs/f2fs/gc.c | 11 +++++++----
 1 file changed, 7 insertions(+), 4 deletions(-)

diff --git a/fs/f2fs/gc.c b/fs/f2fs/gc.c
index 3e1b6d2ff3a7..8029369bb71d 100644
--- a/fs/f2fs/gc.c
+++ b/fs/f2fs/gc.c
@@ -806,11 +806,14 @@ int f2fs_get_victim(struct f2fs_sb_info *sbi, unsigned int *result,
 			goto out;
 		}
 
-		if (sec_usage_check(sbi, GET_SEC_FROM_SEG(sbi, *result)))
+		if (sec_usage_check(sbi, GET_SEC_FROM_SEG(sbi, *result))) {
 			ret = -EBUSY;
-		else
-			p.min_segno = *result;
-		goto out;
+			goto out;
+		}
+		if (gc_type == FG_GC)
+			clear_bit(GET_SEC_FROM_SEG(sbi, *result), dirty_i->victim_secmap);
+		p.min_segno = *result;
+		goto got_result;
 	}
 
 	ret = -ENODATA;
-- 
2.34.1