11 static __le32 ext4_mmp_csum(struct super_block *sb, struct mmp_struct *mmp)  in ext4_mmp_csum()  argument
13 	struct ext4_sb_info *sbi = EXT4_SB(sb);  in ext4_mmp_csum()
22 static int ext4_mmp_csum_verify(struct super_block *sb, struct mmp_struct *mmp)  in ext4_mmp_csum_verify()  argument
24 	if (!ext4_has_metadata_csum(sb))  in ext4_mmp_csum_verify()
27 	return mmp->mmp_checksum == ext4_mmp_csum(sb, mmp);  in ext4_mmp_csum_verify()
30 static void ext4_mmp_csum_set(struct super_block *sb, struct mmp_struct *mmp)  in ext4_mmp_csum_set()  argument
32 	if (!ext4_has_metadata_csum(sb))  in ext4_mmp_csum_set()
35 	mmp->mmp_checksum = ext4_mmp_csum(sb, mmp);  in ext4_mmp_csum_set()
42 static int write_mmp_block_thawed(struct super_block *sb,  in write_mmp_block_thawed()  argument
47 	ext4_mmp_csum_set(sb, mmp);  in write_mmp_block_thawed()
58 static int write_mmp_block(struct super_block *sb, struct buffer_head *bh)  in write_mmp_block()  argument
66 	sb_start_write(sb);  in write_mmp_block()
67 	err = write_mmp_block_thawed(sb, bh);  in write_mmp_block()
68 	sb_end_write(sb);  in write_mmp_block()
76 static int read_mmp_block(struct super_block *sb, struct buffer_head **bh,  in read_mmp_block()  argument
89 		*bh = sb_getblk(sb, mmp_block);  in read_mmp_block()
106 	if (!ext4_mmp_csum_verify(sb, mmp)) {  in read_mmp_block()
114 	ext4_warning(sb, "Error %d while reading MMP block %llu",  in read_mmp_block()
122 void __dump_mmp_msg(struct super_block *sb, struct mmp_struct *mmp,  in __dump_mmp_msg()  argument
125 	__ext4_warning(sb, function, line, "%s", msg);  in __dump_mmp_msg()
126 	__ext4_warning(sb, function, line,  in __dump_mmp_msg()
138 	struct super_block *sb = data;  in kmmpd()  local
139 	struct ext4_super_block *es = EXT4_SB(sb)->s_es;  in kmmpd()
140 	struct buffer_head *bh = EXT4_SB(sb)->s_mmp_bh;  in kmmpd()
165 	while (!kthread_should_stop() && !ext4_forced_shutdown(sb)) {  in kmmpd()
166 		if (!ext4_has_feature_mmp(sb)) {  in kmmpd()
167 			ext4_warning(sb, "kmmpd being stopped since MMP feature"  in kmmpd()
178 		retval = write_mmp_block(sb, bh);  in kmmpd()
185 				ext4_error_err(sb, -retval,  in kmmpd()
206 			retval = read_mmp_block(sb, &bh_check, mmp_block);  in kmmpd()
208 				ext4_error_err(sb, -retval,  in kmmpd()
218 				dump_mmp_msg(sb, mmp_check,  in kmmpd()
222 				ext4_error_err(sb, EBUSY, "abort");  in kmmpd()
246 	retval = write_mmp_block(sb, bh);  in kmmpd()
279 int ext4_multi_mount_protect(struct super_block *sb,  in ext4_multi_mount_protect()  argument
282 	struct ext4_super_block *es = EXT4_SB(sb)->s_es;  in ext4_multi_mount_protect()
292 		ext4_warning(sb, "Invalid MMP block in superblock");  in ext4_multi_mount_protect()
297 	retval = read_mmp_block(sb, &bh, mmp_block);  in ext4_multi_mount_protect()
318 		dump_mmp_msg(sb, mmp, "fsck is running on the filesystem");  in ext4_multi_mount_protect()
328 		ext4_warning(sb, "MMP interval %u higher than expected, please"  in ext4_multi_mount_protect()
332 		ext4_warning(sb, "MMP startup interrupted, failing mount\n");  in ext4_multi_mount_protect()
337 	retval = read_mmp_block(sb, &bh, mmp_block);  in ext4_multi_mount_protect()
342 		dump_mmp_msg(sb, mmp,  in ext4_multi_mount_protect()
359 	retval = write_mmp_block_thawed(sb, bh);  in ext4_multi_mount_protect()
367 		ext4_warning(sb, "MMP startup interrupted, failing mount");  in ext4_multi_mount_protect()
372 	retval = read_mmp_block(sb, &bh, mmp_block);  in ext4_multi_mount_protect()
377 		dump_mmp_msg(sb, mmp,  in ext4_multi_mount_protect()
383 	EXT4_SB(sb)->s_mmp_bh = bh;  in ext4_multi_mount_protect()
392 	EXT4_SB(sb)->s_mmp_tsk = kthread_run(kmmpd, sb, "kmmpd-%.*s",  in ext4_multi_mount_protect()
395 	if (IS_ERR(EXT4_SB(sb)->s_mmp_tsk)) {  in ext4_multi_mount_protect()
396 		EXT4_SB(sb)->s_mmp_tsk = NULL;  in ext4_multi_mount_protect()
397 		ext4_warning(sb, "Unable to create kmmpd thread for %s.",  in ext4_multi_mount_protect()
398 			     sb->s_id);  in ext4_multi_mount_protect()