Commit b237e304 authored by Harshad Shirwadkar's avatar Harshad Shirwadkar Committed by Theodore Ts'o
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ext4: add ability to return parsed options from parse_options 



Before this patch, the function parse_options() was returning
journal_devnum and journal_ioprio variables to the caller. This patch
generalizes that interface to allow parse_options to return any parsed
options to return back to the caller. In this patch series, it gets
used to capture the value of "mb_optimize_scan=%u" mount option.

Signed-off-by: default avatarHarshad Shirwadkar <harshadshirwadkar@gmail.com>
Reviewed-by: default avatarRitesh Harjani <ritesh.list@gmail.com>
Link: https://lore.kernel.org/r/20210401172129.189766-3-harshadshirwadkar@gmail.com


Signed-off-by: default avatarTheodore Ts'o <tytso@mit.edu>
parent 67d25186

fs/ext4/super.c

+30 −21
Original line number Diff line number Diff line
@@ -2090,9 +2090,14 @@ static int ext4_set_test_dummy_encryption(struct super_block *sb, 
	return 1;

}



struct ext4_parsed_options {

	unsigned long journal_devnum;

	unsigned int journal_ioprio;

};



static int handle_mount_opt(struct super_block *sb, char *opt, int token,

			    substring_t *args, unsigned long *journal_devnum,

			    unsigned int *journal_ioprio, int is_remount)

			    substring_t *args, struct ext4_parsed_options *parsed_opts,

			    int is_remount)

{

	struct ext4_sb_info *sbi = EXT4_SB(sb);

	const struct mount_opts *m;
@@ -2249,7 +2254,7 @@ static int handle_mount_opt(struct super_block *sb, char *opt, int token, 
				 "Cannot specify journal on remount");

			return -1;

		}

		*journal_devnum = arg;

		parsed_opts->journal_devnum = arg;

	} else if (token == Opt_journal_path) {

		char *journal_path;

		struct inode *journal_inode;
@@ -2285,7 +2290,7 @@ static int handle_mount_opt(struct super_block *sb, char *opt, int token, 
			return -1;

		}



		*journal_devnum = new_encode_dev(journal_inode->i_rdev);

		parsed_opts->journal_devnum = new_encode_dev(journal_inode->i_rdev);

		path_put(&path);

		kfree(journal_path);

	} else if (token == Opt_journal_ioprio) {
@@ -2294,7 +2299,7 @@ static int handle_mount_opt(struct super_block *sb, char *opt, int token, 
				 " (must be 0-7)");

			return -1;

		}

		*journal_ioprio =

		parsed_opts->journal_ioprio =

			IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, arg);

	} else if (token == Opt_test_dummy_encryption) {

		return ext4_set_test_dummy_encryption(sb, opt, &args[0],
@@ -2411,8 +2416,7 @@ static int handle_mount_opt(struct super_block *sb, char *opt, int token, 
}



static int parse_options(char *options, struct super_block *sb,

			 unsigned long *journal_devnum,

			 unsigned int *journal_ioprio,

			 struct ext4_parsed_options *ret_opts,

			 int is_remount)

{

	struct ext4_sb_info __maybe_unused *sbi = EXT4_SB(sb);
@@ -2432,8 +2436,8 @@ static int parse_options(char *options, struct super_block *sb, 
		 */

		args[0].to = args[0].from = NULL;

		token = match_token(p, tokens, args);

		if (handle_mount_opt(sb, p, token, args, journal_devnum,

				     journal_ioprio, is_remount) < 0)

		if (handle_mount_opt(sb, p, token, args, ret_opts,

				     is_remount) < 0)

			return 0;

	}

#ifdef CONFIG_QUOTA
@@ -4015,7 +4019,6 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent) 
	ext4_fsblk_t sb_block = get_sb_block(&data);

	ext4_fsblk_t logical_sb_block;

	unsigned long offset = 0;

	unsigned long journal_devnum = 0;

	unsigned long def_mount_opts;

	struct inode *root;

	const char *descr;
@@ -4026,8 +4029,12 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent) 
	int needs_recovery, has_huge_files;

	__u64 blocks_count;

	int err = 0;

	unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;

	ext4_group_t first_not_zeroed;

	struct ext4_parsed_options parsed_opts;



	/* Set defaults for the variables that will be set during parsing */

	parsed_opts.journal_ioprio = DEFAULT_JOURNAL_IOPRIO;

	parsed_opts.journal_devnum = 0;



	if ((data && !orig_data) || !sbi)

		goto out_free_base;
@@ -4273,8 +4280,7 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent) 
					      GFP_KERNEL);

		if (!s_mount_opts)

			goto failed_mount;

		if (!parse_options(s_mount_opts, sb, &journal_devnum,

				   &journal_ioprio, 0)) {

		if (!parse_options(s_mount_opts, sb, &parsed_opts, 0)) {

			ext4_msg(sb, KERN_WARNING,

				 "failed to parse options in superblock: %s",

				 s_mount_opts);
@@ -4282,8 +4288,7 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent) 
		kfree(s_mount_opts);

	}

	sbi->s_def_mount_opt = sbi->s_mount_opt;

	if (!parse_options((char *) data, sb, &journal_devnum,

			   &journal_ioprio, 0))

	if (!parse_options((char *) data, sb, &parsed_opts, 0))

		goto failed_mount;



#ifdef CONFIG_UNICODE
@@ -4768,7 +4773,7 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent) 
	 * root first: it may be modified in the journal!

	 */

	if (!test_opt(sb, NOLOAD) && ext4_has_feature_journal(sb)) {

		err = ext4_load_journal(sb, es, journal_devnum);

		err = ext4_load_journal(sb, es, parsed_opts.journal_devnum);

		if (err)

			goto failed_mount3a;

	} else if (test_opt(sb, NOLOAD) && !sb_rdonly(sb) &&
@@ -4868,7 +4873,7 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent) 
		goto failed_mount_wq;

	}



	set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);

	set_task_ioprio(sbi->s_journal->j_task, parsed_opts.journal_ioprio);



	sbi->s_journal->j_submit_inode_data_buffers =

		ext4_journal_submit_inode_data_buffers;
@@ -5807,13 +5812,16 @@ static int ext4_remount(struct super_block *sb, int *flags, char *data) 
	struct ext4_mount_options old_opts;

	int enable_quota = 0;

	ext4_group_t g;

	unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;

	int err = 0;

#ifdef CONFIG_QUOTA

	int i, j;

	char *to_free[EXT4_MAXQUOTAS];

#endif

	char *orig_data = kstrdup(data, GFP_KERNEL);

	struct ext4_parsed_options parsed_opts;



	parsed_opts.journal_ioprio = DEFAULT_JOURNAL_IOPRIO;

	parsed_opts.journal_devnum = 0;



	if (data && !orig_data)

		return -ENOMEM;
@@ -5844,7 +5852,8 @@ static int ext4_remount(struct super_block *sb, int *flags, char *data) 
			old_opts.s_qf_names[i] = NULL;

#endif

	if (sbi->s_journal && sbi->s_journal->j_task->io_context)

		journal_ioprio = sbi->s_journal->j_task->io_context->ioprio;

		parsed_opts.journal_ioprio =

			sbi->s_journal->j_task->io_context->ioprio;



	/*

	 * Some options can be enabled by ext4 and/or by VFS mount flag
@@ -5854,7 +5863,7 @@ static int ext4_remount(struct super_block *sb, int *flags, char *data) 
	vfs_flags = SB_LAZYTIME | SB_I_VERSION;

	sb->s_flags = (sb->s_flags & ~vfs_flags) | (*flags & vfs_flags);



	if (!parse_options(data, sb, NULL, &journal_ioprio, 1)) {

	if (!parse_options(data, sb, &parsed_opts, 1)) {

		err = -EINVAL;

		goto restore_opts;

	}
@@ -5904,7 +5913,7 @@ static int ext4_remount(struct super_block *sb, int *flags, char *data) 


	if (sbi->s_journal) {

		ext4_init_journal_params(sb, sbi->s_journal);

		set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);

		set_task_ioprio(sbi->s_journal->j_task, parsed_opts.journal_ioprio);

	}



	/* Flush outstanding errors before changing fs state */