aboutsummaryrefslogtreecommitdiffstats
path: root/fs/ext4/mmp.c
diff options
context:
space:
mode:
Diffstat (limited to 'fs/ext4/mmp.c')
-rw-r--r--fs/ext4/mmp.c99
1 files changed, 46 insertions, 53 deletions
diff --git a/fs/ext4/mmp.c b/fs/ext4/mmp.c
index 87f7551c5132..588cb09c5291 100644
--- a/fs/ext4/mmp.c
+++ b/fs/ext4/mmp.c
@@ -52,11 +52,11 @@ static int write_mmp_block(struct super_block *sb, struct buffer_head *bh)
lock_buffer(bh);
bh->b_end_io = end_buffer_write_sync;
get_bh(bh);
- submit_bh(REQ_OP_WRITE, REQ_SYNC | REQ_META | REQ_PRIO, bh);
+ submit_bh(REQ_OP_WRITE | REQ_SYNC | REQ_META | REQ_PRIO, bh);
wait_on_buffer(bh);
sb_end_write(sb);
if (unlikely(!buffer_uptodate(bh)))
- return 1;
+ return -EIO;
return 0;
}
@@ -85,15 +85,11 @@ static int read_mmp_block(struct super_block *sb, struct buffer_head **bh,
}
}
- get_bh(*bh);
lock_buffer(*bh);
- (*bh)->b_end_io = end_buffer_read_sync;
- submit_bh(REQ_OP_READ, REQ_META | REQ_PRIO, *bh);
- wait_on_buffer(*bh);
- if (!buffer_uptodate(*bh)) {
- ret = -EIO;
+ ret = ext4_read_bh(*bh, REQ_META | REQ_PRIO, NULL);
+ if (ret)
goto warn_exit;
- }
+
mmp = (struct mmp_struct *)((*bh)->b_data);
if (le32_to_cpu(mmp->mmp_magic) != EXT4_MMP_MAGIC) {
ret = -EFSCORRUPTED;
@@ -131,9 +127,9 @@ void __dump_mmp_msg(struct super_block *sb, struct mmp_struct *mmp,
*/
static int kmmpd(void *data)
{
- struct super_block *sb = ((struct mmpd_data *) data)->sb;
- struct buffer_head *bh = ((struct mmpd_data *) data)->bh;
+ struct super_block *sb = data;
struct ext4_super_block *es = EXT4_SB(sb)->s_es;
+ struct buffer_head *bh = EXT4_SB(sb)->s_mmp_bh;
struct mmp_struct *mmp;
ext4_fsblk_t mmp_block;
u32 seq = 0;
@@ -142,7 +138,7 @@ static int kmmpd(void *data)
unsigned mmp_check_interval;
unsigned long last_update_time;
unsigned long diff;
- int retval;
+ int retval = 0;
mmp_block = le64_to_cpu(es->s_mmp_block);
mmp = (struct mmp_struct *)(bh->b_data);
@@ -154,13 +150,16 @@ static int kmmpd(void *data)
mmp_check_interval = max(EXT4_MMP_CHECK_MULT * mmp_update_interval,
EXT4_MMP_MIN_CHECK_INTERVAL);
mmp->mmp_check_interval = cpu_to_le16(mmp_check_interval);
- BUILD_BUG_ON(sizeof(mmp->mmp_bdevname) < BDEVNAME_SIZE);
- bdevname(bh->b_bdev, mmp->mmp_bdevname);
memcpy(mmp->mmp_nodename, init_utsname()->nodename,
sizeof(mmp->mmp_nodename));
- while (!kthread_should_stop()) {
+ while (!kthread_should_stop() && !sb_rdonly(sb)) {
+ if (!ext4_has_feature_mmp(sb)) {
+ ext4_warning(sb, "kmmpd being stopped since MMP feature"
+ " has been disabled.");
+ goto wait_to_exit;
+ }
if (++seq > EXT4_MMP_SEQ_MAX)
seq = 1;
@@ -175,22 +174,12 @@ static int kmmpd(void *data)
*/
if (retval) {
if ((failed_writes % 60) == 0) {
- ext4_set_errno(sb, -retval);
- ext4_error(sb, "Error writing to MMP block");
+ ext4_error_err(sb, -retval,
+ "Error writing to MMP block");
}
failed_writes++;
}
- if (!(le32_to_cpu(es->s_feature_incompat) &
- EXT4_FEATURE_INCOMPAT_MMP)) {
- ext4_warning(sb, "kmmpd being stopped since MMP feature"
- " has been disabled.");
- goto exit_thread;
- }
-
- if (sb_rdonly(sb))
- break;
-
diff = jiffies - last_update_time;
if (diff < mmp_update_interval * HZ)
schedule_timeout_interruptible(mmp_update_interval *
@@ -208,10 +197,10 @@ static int kmmpd(void *data)
retval = read_mmp_block(sb, &bh_check, mmp_block);
if (retval) {
- ext4_set_errno(sb, -retval);
- ext4_error(sb, "error reading MMP data: %d",
- retval);
- goto exit_thread;
+ ext4_error_err(sb, -retval,
+ "error reading MMP data: %d",
+ retval);
+ goto wait_to_exit;
}
mmp_check = (struct mmp_struct *)(bh_check->b_data);
@@ -222,11 +211,10 @@ static int kmmpd(void *data)
"Error while updating MMP info. "
"The filesystem seems to have been"
" multiply mounted.");
- ext4_set_errno(sb, EBUSY);
- ext4_error(sb, "abort");
+ ext4_error_err(sb, EBUSY, "abort");
put_bh(bh_check);
retval = -EBUSY;
- goto exit_thread;
+ goto wait_to_exit;
}
put_bh(bh_check);
}
@@ -249,13 +237,25 @@ static int kmmpd(void *data)
retval = write_mmp_block(sb, bh);
-exit_thread:
- EXT4_SB(sb)->s_mmp_tsk = NULL;
- kfree(data);
- brelse(bh);
+wait_to_exit:
+ while (!kthread_should_stop()) {
+ set_current_state(TASK_INTERRUPTIBLE);
+ if (!kthread_should_stop())
+ schedule();
+ }
+ set_current_state(TASK_RUNNING);
return retval;
}
+void ext4_stop_mmpd(struct ext4_sb_info *sbi)
+{
+ if (sbi->s_mmp_tsk) {
+ kthread_stop(sbi->s_mmp_tsk);
+ brelse(sbi->s_mmp_bh);
+ sbi->s_mmp_tsk = NULL;
+ }
+}
+
/*
* Get a random new sequence number but make sure it is not greater than
* EXT4_MMP_SEQ_MAX.
@@ -265,7 +265,7 @@ static unsigned int mmp_new_seq(void)
u32 new_seq;
do {
- new_seq = prandom_u32();
+ new_seq = get_random_u32();
} while (new_seq > EXT4_MMP_SEQ_MAX);
return new_seq;
@@ -280,7 +280,6 @@ int ext4_multi_mount_protect(struct super_block *sb,
struct ext4_super_block *es = EXT4_SB(sb)->s_es;
struct buffer_head *bh = NULL;
struct mmp_struct *mmp = NULL;
- struct mmpd_data *mmpd_data;
u32 seq;
unsigned int mmp_check_interval = le16_to_cpu(es->s_mmp_update_interval);
unsigned int wait_time = 0;
@@ -369,24 +368,20 @@ skip:
goto failed;
}
- mmpd_data = kmalloc(sizeof(*mmpd_data), GFP_KERNEL);
- if (!mmpd_data) {
- ext4_warning(sb, "not enough memory for mmpd_data");
- goto failed;
- }
- mmpd_data->sb = sb;
- mmpd_data->bh = bh;
+ EXT4_SB(sb)->s_mmp_bh = bh;
+
+ BUILD_BUG_ON(sizeof(mmp->mmp_bdevname) < BDEVNAME_SIZE);
+ snprintf(mmp->mmp_bdevname, sizeof(mmp->mmp_bdevname),
+ "%pg", bh->b_bdev);
/*
* Start a kernel thread to update the MMP block periodically.
*/
- EXT4_SB(sb)->s_mmp_tsk = kthread_run(kmmpd, mmpd_data, "kmmpd-%.*s",
+ EXT4_SB(sb)->s_mmp_tsk = kthread_run(kmmpd, sb, "kmmpd-%.*s",
(int)sizeof(mmp->mmp_bdevname),
- bdevname(bh->b_bdev,
- mmp->mmp_bdevname));
+ mmp->mmp_bdevname);
if (IS_ERR(EXT4_SB(sb)->s_mmp_tsk)) {
EXT4_SB(sb)->s_mmp_tsk = NULL;
- kfree(mmpd_data);
ext4_warning(sb, "Unable to create kmmpd thread for %s.",
sb->s_id);
goto failed;
@@ -398,5 +393,3 @@ failed:
brelse(bh);
return 1;
}
-
-
Copyright © 1996 – 2023 Jason A. Donenfeld. All Rights Reverse Engineered.