linux-kernel - [PATCH v1 1/1] ubifs: only check replay with inode type to judge if inode linked

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Message-ID: <20210316085214.25024-2-guochun.mao@mediatek.com>
Date:   Tue, 16 Mar 2021 16:52:14 +0800
From:   <guochun.mao@...iatek.com>
To:     Richard Weinberger <richard@....at>
CC:     Matthias Brugger <matthias.bgg@...il.com>,
        <linux-mtd@...ts.infradead.org>, <linux-kernel@...r.kernel.org>,
        <linux-arm-kernel@...ts.infradead.org>,
        <linux-mediatek@...ts.infradead.org>,
        <srv_heupstream@...iatek.com>,
        Guochun Mao <guochun.mao@...iatek.com>
Subject: [PATCH v1 1/1] ubifs: only check replay with inode type to judge if inode linked

From: Guochun Mao <guochun.mao@...iatek.com>

Conside the following case, it just write a big file into flash,
when complete writing, delete the file, and then power off promptly.
Next time power on, we'll get a replay list like:
...
LEB 1105:211344 len 4144 deletion 0 sqnum 428783 key type 1 inode 80
LEB 15:233544 len 160 deletion 1 sqnum 428785 key type 0 inode 80
LEB 1105:215488 len 4144 deletion 0 sqnum 428787 key type 1 inode 80
...
In the replay list, data nodes' deletion are 0, and the inode node's
deletion is 1. In current logic, the file's dentry will be removed,
but inode and the flash space it occupied will be reserved.
User will see that much free space been disappeared.

We only need to check the deletion value of the following inode type
node of the replay entry.

Signed-off-by: Guochun Mao <guochun.mao@...iatek.com>
---
 fs/ubifs/replay.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/fs/ubifs/replay.c b/fs/ubifs/replay.c
index 0f8a6a16421b..1929ec63a0cb 100644
--- a/fs/ubifs/replay.c
+++ b/fs/ubifs/replay.c
@@ -223,7 +223,8 @@ static bool inode_still_linked(struct ubifs_info *c, struct replay_entry *rino)
 	 */
 	list_for_each_entry_reverse(r, &c->replay_list, list) {
 		ubifs_assert(c, r->sqnum >= rino->sqnum);
-		if (key_inum(c, &r->key) == key_inum(c, &rino->key))
+		if (key_inum(c, &r->key) == key_inum(c, &rino->key) &&
+		    key_type(c, &r->key) == UBIFS_INO_KEY)
 			return r->deletion == 0;

 	}
-- 
2.18.0