From 102a0743326a03cd1a1202ceda21e175b7d3575c Mon Sep 17 00:00:00 2001
From: hc <hc@nodka.com>
Date: Tue, 20 Feb 2024 01:20:52 +0000
Subject: [PATCH] add new system file
---
kernel/fs/ext4/mmp.c | 39 +++++++++++++++++++++++++++++----------
1 files changed, 29 insertions(+), 10 deletions(-)
diff --git a/kernel/fs/ext4/mmp.c b/kernel/fs/ext4/mmp.c
index bc364c1..7a9a8ed 100644
--- a/kernel/fs/ext4/mmp.c
+++ b/kernel/fs/ext4/mmp.c
@@ -39,26 +39,34 @@
* Write the MMP block using REQ_SYNC to try to get the block on-disk
* faster.
*/
-static int write_mmp_block(struct super_block *sb, struct buffer_head *bh)
+static int write_mmp_block_thawed(struct super_block *sb,
+ struct buffer_head *bh)
{
struct mmp_struct *mmp = (struct mmp_struct *)(bh->b_data);
- /*
- * We protect against freezing so that we don't create dirty buffers
- * on frozen filesystem.
- */
- sb_start_write(sb);
ext4_mmp_csum_set(sb, mmp);
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);
wait_on_buffer(bh);
- sb_end_write(sb);
if (unlikely(!buffer_uptodate(bh)))
return -EIO;
-
return 0;
+}
+
+static int write_mmp_block(struct super_block *sb, struct buffer_head *bh)
+{
+ int err;
+
+ /*
+ * We protect against freezing so that we don't create dirty buffers
+ * on frozen filesystem.
+ */
+ sb_start_write(sb);
+ err = write_mmp_block_thawed(sb, bh);
+ sb_end_write(sb);
+ return err;
}
/*
@@ -290,6 +298,7 @@
if (mmp_block < le32_to_cpu(es->s_first_data_block) ||
mmp_block >= ext4_blocks_count(es)) {
ext4_warning(sb, "Invalid MMP block in superblock");
+ retval = -EINVAL;
goto failed;
}
@@ -315,6 +324,7 @@
if (seq == EXT4_MMP_SEQ_FSCK) {
dump_mmp_msg(sb, mmp, "fsck is running on the filesystem");
+ retval = -EBUSY;
goto failed;
}
@@ -328,6 +338,7 @@
if (schedule_timeout_interruptible(HZ * wait_time) != 0) {
ext4_warning(sb, "MMP startup interrupted, failing mount\n");
+ retval = -ETIMEDOUT;
goto failed;
}
@@ -338,6 +349,7 @@
if (seq != le32_to_cpu(mmp->mmp_seq)) {
dump_mmp_msg(sb, mmp,
"Device is already active on another node.");
+ retval = -EBUSY;
goto failed;
}
@@ -348,7 +360,11 @@
seq = mmp_new_seq();
mmp->mmp_seq = cpu_to_le32(seq);
- retval = write_mmp_block(sb, bh);
+ /*
+ * On mount / remount we are protected against fs freezing (by s_umount
+ * semaphore) and grabbing freeze protection upsets lockdep
+ */
+ retval = write_mmp_block_thawed(sb, bh);
if (retval)
goto failed;
@@ -357,6 +373,7 @@
*/
if (schedule_timeout_interruptible(HZ * wait_time) != 0) {
ext4_warning(sb, "MMP startup interrupted, failing mount");
+ retval = -ETIMEDOUT;
goto failed;
}
@@ -367,6 +384,7 @@
if (seq != le32_to_cpu(mmp->mmp_seq)) {
dump_mmp_msg(sb, mmp,
"Device is already active on another node.");
+ retval = -EBUSY;
goto failed;
}
@@ -383,6 +401,7 @@
EXT4_SB(sb)->s_mmp_tsk = NULL;
ext4_warning(sb, "Unable to create kmmpd thread for %s.",
sb->s_id);
+ retval = -ENOMEM;
goto failed;
}
@@ -390,5 +409,5 @@
failed:
brelse(bh);
- return 1;
+ return retval;
}
--
Gitblit v1.6.2