From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 1B377368D6B for ; Thu, 23 Jul 2026 17:22:22 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784827343; cv=none; b=msUdG6PUT0WLYyenuqMGaI6OvtZz5nR1KsCH7BN3880oZBkltIdhquw0TE0K9S/lVV8MGXlNlEzrgtX8MN4BHY8GXfKe5m0OsUHx1Gudaof4ygyxukIkeg4i93RPs2IzLb/T7OeYSGB5sqaaggsqJKhGeHT2apK6O1ZPLbrKQeo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784827343; c=relaxed/simple; bh=j5WCdHhHSkZeR8Eg8tGyVuiR5d4ymb+wt2M4W0jBHxI=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=iLi0XMYqIdUOS/ho7xU3ZkOYVlKd92/pdpPhUsEohdpRceAfcgb2JndzLlTuMW9gcYiBs4sBtyPGW2NgUHWVNlhCegTbKC0BVwSKNE8mUVSx31ZjxC9FnHiMNvevCujuwh4PnMpDKzaf+1oZU+qLje/R03nMTPlnRa/R59Tiy7U= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 Received: by smtp.kernel.org (Postfix) with ESMTPSA id D10BD1F000E9; Thu, 23 Jul 2026 17:22:20 +0000 (UTC) From: Sasha Levin To: stable@vger.kernel.org Cc: Harshad Shirwadkar , Theodore Ts'o , Sasha Levin Subject: [PATCH 5.10.y 1/2] jbd2: add a helper to find out number of fast commit blocks Date: Thu, 23 Jul 2026 13:22:00 -0400 Message-ID: <20260723172201.3413360-1-sashal@kernel.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <2026072041-pork-untapped-b293@gregkh> References: <2026072041-pork-untapped-b293@gregkh> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: Harshad Shirwadkar [ Upstream commit 9bd23c31f392bda88618008f27fd52ee9e0fac38 ] Add a helper to read number of fast commit blocks from jbd2 superblock and also rename the JBD2_MIN_FC_BLKS to JBD2_DEFAULT_FAST_COMMIT_BLOCKS since this constant is just the default number of fast commit blocks to use in case number of fast commit blocks isn't set in jbd2 superblock. Signed-off-by: Harshad Shirwadkar Link: https://lore.kernel.org/r/20201120202232.2240293-2-harshadshirwadkar@gmail.com Signed-off-by: Theodore Ts'o Stable-dep-of: 289a2ca0c9b7 ("jbd2: fix integer underflow in jbd2_journal_initialize_fast_commit()") Signed-off-by: Sasha Levin --- fs/jbd2/journal.c | 8 ++------ include/linux/jbd2.h | 9 ++++++++- 2 files changed, 10 insertions(+), 7 deletions(-) diff --git a/fs/jbd2/journal.c b/fs/jbd2/journal.c index 14b176d63482df..cbf56b18521666 100644 --- a/fs/jbd2/journal.c +++ b/fs/jbd2/journal.c @@ -1884,9 +1884,7 @@ static int load_superblock(journal_t *journal) if (jbd2_has_feature_fast_commit(journal)) { journal->j_fc_last = be32_to_cpu(sb->s_maxlen); - num_fc_blocks = be32_to_cpu(sb->s_num_fc_blks); - if (!num_fc_blocks) - num_fc_blocks = JBD2_MIN_FC_BLOCKS; + num_fc_blocks = jbd2_journal_get_num_fc_blks(sb); if (journal->j_last - num_fc_blocks >= JBD2_MIN_JOURNAL_BLOCKS) journal->j_last = journal->j_fc_last - num_fc_blocks; journal->j_fc_first = journal->j_last + 1; @@ -2117,9 +2115,7 @@ jbd2_journal_initialize_fast_commit(journal_t *journal) journal_superblock_t *sb = journal->j_superblock; unsigned long long num_fc_blks; - num_fc_blks = be32_to_cpu(sb->s_num_fc_blks); - if (num_fc_blks == 0) - num_fc_blks = JBD2_MIN_FC_BLOCKS; + num_fc_blks = jbd2_journal_get_num_fc_blks(sb); if (journal->j_last - num_fc_blks < JBD2_MIN_JOURNAL_BLOCKS) return -ENOSPC; diff --git a/include/linux/jbd2.h b/include/linux/jbd2.h index 80f573d1b3b83b..f5826f99fe9aa1 100644 --- a/include/linux/jbd2.h +++ b/include/linux/jbd2.h @@ -68,7 +68,7 @@ extern void *jbd2_alloc(size_t size, gfp_t flags); extern void jbd2_free(void *ptr, size_t size); #define JBD2_MIN_JOURNAL_BLOCKS 1024 -#define JBD2_MIN_FC_BLOCKS 256 +#define JBD2_DEFAULT_FAST_COMMIT_BLOCKS 256 #ifdef __KERNEL__ @@ -1686,6 +1686,13 @@ static inline int jbd2_journal_has_csum_v2or3(journal_t *journal) return journal->j_chksum_driver != NULL; } +static inline int jbd2_journal_get_num_fc_blks(journal_superblock_t *jsb) +{ + int num_fc_blocks = be32_to_cpu(jsb->s_num_fc_blks); + + return num_fc_blocks ? num_fc_blocks : JBD2_DEFAULT_FAST_COMMIT_BLOCKS; +} + /* * Return number of free blocks in the log. Must be called under j_state_lock. */ -- 2.53.0