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Date: Fri, 9 Oct 2015 13:09:59 +0400
From: Dmitry Monakhov <dmonakhov@...nvz.org>
To: linux-ext4@...r.kernel.org
Cc: tytso@....edu, Dmitry Monakhov <dmonakhov@...nvz.org>
Subject: [PATCH 2/2] ext4: do not allow journal_opts for fs w/o journal
It is appeared that we can pass journal related mount options and such options
be shown in /proc/mounts
Example:
#mkfs.ext4 -F /dev/vdb
#tune2fs -O ^has_journal /dev/vdb
#mount /dev/vdb /mnt/ -ocommit=20,journal_async_commit
#cat /proc/mounts | grep /mnt
/dev/vdb /mnt ext4 rw,relatime,journal_checksum,journal_async_commit,commit=20,data=ordered 0 0
But options:"journal_checksum,journal_async_commit,commit=20,data=ordered" has
nothing with reality because there is no jornall at all.
This patch disallow following options for journalless configurations:
- journal_checksum
- journal_async_commit
- commit=%ld
- data={writeback,ordered,journal}
Signed-off-by: Dmitry Monakhov <dmonakhov@...nvz.org>
---
fs/ext4/ext4.h | 3 +++
fs/ext4/super.c | 31 +++++++++++++++++++++++++++++--
2 files changed, 32 insertions(+), 2 deletions(-)
diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
index 3f248c9..871cdc6 100644
--- a/fs/ext4/ext4.h
+++ b/fs/ext4/ext4.h
@@ -1019,6 +1019,9 @@ struct ext4_inode_info {
#define EXT4_MOUNT2_HURD_COMPAT 0x00000004 /* Support HURD-castrated
file systems */
+#define EXT4_MOUNT2_EXPLICIT_JOURNAL_CHECKSUM 0x00000008 /* User explicitly
+ specified journal checksum */
+
#define clear_opt(sb, opt) EXT4_SB(sb)->s_mount_opt &= \
~EXT4_MOUNT_##opt
#define set_opt(sb, opt) EXT4_SB(sb)->s_mount_opt |= \
diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index e91f6d4..a29b32b 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -1371,10 +1371,10 @@ static const struct mount_opts {
{Opt_nojournal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
MOPT_EXT4_ONLY | MOPT_CLEAR},
{Opt_journal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
- MOPT_EXT4_ONLY | MOPT_SET},
+ MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
{Opt_journal_async_commit, (EXT4_MOUNT_JOURNAL_ASYNC_COMMIT |
EXT4_MOUNT_JOURNAL_CHECKSUM),
- MOPT_EXT4_ONLY | MOPT_SET},
+ MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
{Opt_noload, EXT4_MOUNT_NOLOAD, MOPT_NO_EXT2 | MOPT_SET},
{Opt_err_panic, EXT4_MOUNT_ERRORS_PANIC, MOPT_SET | MOPT_CLEAR_ERR},
{Opt_err_ro, EXT4_MOUNT_ERRORS_RO, MOPT_SET | MOPT_CLEAR_ERR},
@@ -1506,6 +1506,8 @@ static int handle_mount_opt(struct super_block *sb, char *opt, int token,
if (m->flags & MOPT_EXPLICIT) {
if (m->mount_opt & EXT4_MOUNT_DELALLOC) {
set_opt2(sb, EXPLICIT_DELALLOC);
+ } else if (m->mount_opt & EXT4_MOUNT_JOURNAL_CHECKSUM) {
+ set_opt2(sb, EXPLICIT_JOURNAL_CHECKSUM);
} else
return -1;
}
@@ -3675,6 +3677,31 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent)
"suppressed and not mounted read-only");
goto failed_mount_wq;
} else {
+ /* Nojournal mode, all journal mount options are illegal */
+ if (test_opt2(sb, EXPLICIT_JOURNAL_CHECKSUM)) {
+ ext4_msg(sb, KERN_ERR, "can't mount with "
+ "journal_checksum, fs mounted w/o journal");
+ goto failed_mount_wq;
+ }
+ if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
+ ext4_msg(sb, KERN_ERR, "can't mount with "
+ "journal_async_commit, fs mounted w/o journal");
+ goto failed_mount_wq;
+ }
+ if (sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ) {
+ ext4_msg(sb, KERN_ERR, "can't mount with "
+ "commit=%lu, fs mounted w/o journal",
+ sbi->s_commit_interval / HZ);
+ goto failed_mount_wq;
+ }
+ if (EXT4_MOUNT_DATA_FLAGS &
+ (sbi->s_mount_opt ^ sbi->s_def_mount_opt)) {
+ ext4_msg(sb, KERN_ERR, "can't mount with "
+ "data=, fs mounted w/o journal");
+ goto failed_mount_wq;
+ }
+ sbi->s_def_mount_opt &= EXT4_MOUNT_JOURNAL_CHECKSUM;
+ clear_opt(sb, JOURNAL_CHECKSUM);
clear_opt(sb, DATA_FLAGS);
sbi->s_journal = NULL;
needs_recovery = 0;
--
1.7.1
--
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