super.c

linux 内核源代码

		 (1 << REISERFS_LARGETAIL) | (1 << REISERFS_SMALLTAIL)},
		{"conv",.setmask = 1 << REISERFS_CONVERT},
		{"attrs",.setmask = 1 << REISERFS_ATTRS},
		{"noattrs",.clrmask = 1 << REISERFS_ATTRS},
#ifdef CONFIG_REISERFS_FS_XATTR
		{"user_xattr",.setmask = 1 << REISERFS_XATTRS_USER},
		{"nouser_xattr",.clrmask = 1 << REISERFS_XATTRS_USER},
#else
		{"user_xattr",.setmask = 1 << REISERFS_UNSUPPORTED_OPT},
		{"nouser_xattr",.clrmask = 1 << REISERFS_UNSUPPORTED_OPT},
#endif
#ifdef CONFIG_REISERFS_FS_POSIX_ACL
		{"acl",.setmask = 1 << REISERFS_POSIXACL},
		{"noacl",.clrmask = 1 << REISERFS_POSIXACL},
#else
		{"acl",.setmask = 1 << REISERFS_UNSUPPORTED_OPT},
		{"noacl",.clrmask = 1 << REISERFS_UNSUPPORTED_OPT},
#endif
		{.option_name = "nolog"},
		{"replayonly",.setmask = 1 << REPLAYONLY},
		{"block-allocator",.arg_required = 'a',.values = balloc},
		{"data",.arg_required = 'd',.values = logging_mode},
		{"barrier",.arg_required = 'b',.values = barrier_mode},
		{"resize",.arg_required = 'r',.values = NULL},
		{"jdev",.arg_required = 'j',.values = NULL},
		{"nolargeio",.arg_required = 'w',.values = NULL},
		{"commit",.arg_required = 'c',.values = NULL},
		{"usrquota",.setmask = 1 << REISERFS_QUOTA},
		{"grpquota",.setmask = 1 << REISERFS_QUOTA},
		{"noquota",.clrmask = 1 << REISERFS_QUOTA},
		{"errors",.arg_required = 'e',.values = error_actions},
		{"usrjquota",.arg_required =
		 'u' | (1 << REISERFS_OPT_ALLOWEMPTY),.values = NULL},
		{"grpjquota",.arg_required =
		 'g' | (1 << REISERFS_OPT_ALLOWEMPTY),.values = NULL},
		{"jqfmt",.arg_required = 'f',.values = NULL},
		{.option_name = NULL}
	};

	*blocks = 0;
	if (!options || !*options)
		/* use default configuration: create tails, journaling on, no
		   conversion to newest format */
		return 1;

	for (pos = options; pos;) {
		c = reiserfs_getopt(s, &pos, opts, &arg, mount_options);
		if (c == -1)
			/* wrong option is given */
			return 0;

		if (c == 'r') {
			char *p;

			p = NULL;
			/* "resize=NNN" or "resize=auto" */

			if (!strcmp(arg, "auto")) {
				/* From JFS code, to auto-get the size. */
				*blocks =
				    s->s_bdev->bd_inode->i_size >> s->
				    s_blocksize_bits;
			} else {
				*blocks = simple_strtoul(arg, &p, 0);
				if (*p != '\0') {
					/* NNN does not look like a number */
					reiserfs_warning(s,
							 "reiserfs_parse_options: bad value %s",
							 arg);
					return 0;
				}
			}
		}

		if (c == 'c') {
			char *p = NULL;
			unsigned long val = simple_strtoul(arg, &p, 0);
			/* commit=NNN (time in seconds) */
			if (*p != '\0' || val >= (unsigned int)-1) {
				reiserfs_warning(s,
						 "reiserfs_parse_options: bad value %s",
						 arg);
				return 0;
			}
			*commit_max_age = (unsigned int)val;
		}

		if (c == 'w') {
			reiserfs_warning(s, "reiserfs: nolargeio option is no longer supported");
			return 0;
		}

		if (c == 'j') {
			if (arg && *arg && jdev_name) {
				if (*jdev_name) {	//Hm, already assigned?
					reiserfs_warning(s,
							 "reiserfs_parse_options: journal device was already  specified to be %s",
							 *jdev_name);
					return 0;
				}
				*jdev_name = arg;
			}
		}
#ifdef CONFIG_QUOTA
		if (c == 'u' || c == 'g') {
			int qtype = c == 'u' ? USRQUOTA : GRPQUOTA;

			if (sb_any_quota_enabled(s)) {
				reiserfs_warning(s,
						 "reiserfs_parse_options: cannot change journalled quota options when quota turned on.");
				return 0;
			}
			if (*arg) {	/* Some filename specified? */
				if (REISERFS_SB(s)->s_qf_names[qtype]
				    && strcmp(REISERFS_SB(s)->s_qf_names[qtype],
					      arg)) {
					reiserfs_warning(s,
							 "reiserfs_parse_options: %s quota file already specified.",
							 QTYPE2NAME(qtype));
					return 0;
				}
				if (strchr(arg, '/')) {
					reiserfs_warning(s,
							 "reiserfs_parse_options: quotafile must be on filesystem root.");
					return 0;
				}
				REISERFS_SB(s)->s_qf_names[qtype] =
				    kmalloc(strlen(arg) + 1, GFP_KERNEL);
				if (!REISERFS_SB(s)->s_qf_names[qtype]) {
					reiserfs_warning(s,
							 "reiserfs_parse_options: not enough memory for storing quotafile name.");
					return 0;
				}
				strcpy(REISERFS_SB(s)->s_qf_names[qtype], arg);
				*mount_options |= 1 << REISERFS_QUOTA;
			} else {
				kfree(REISERFS_SB(s)->s_qf_names[qtype]);
				REISERFS_SB(s)->s_qf_names[qtype] = NULL;
			}
		}
		if (c == 'f') {
			if (!strcmp(arg, "vfsold"))
				REISERFS_SB(s)->s_jquota_fmt = QFMT_VFS_OLD;
			else if (!strcmp(arg, "vfsv0"))
				REISERFS_SB(s)->s_jquota_fmt = QFMT_VFS_V0;
			else {
				reiserfs_warning(s,
						 "reiserfs_parse_options: unknown quota format specified.");
				return 0;
			}
		}
#else
		if (c == 'u' || c == 'g' || c == 'f') {
			reiserfs_warning(s,
					 "reiserfs_parse_options: journalled quota options not supported.");
			return 0;
		}
#endif
	}

#ifdef CONFIG_QUOTA
	if (!REISERFS_SB(s)->s_jquota_fmt
	    && (REISERFS_SB(s)->s_qf_names[USRQUOTA]
		|| REISERFS_SB(s)->s_qf_names[GRPQUOTA])) {
		reiserfs_warning(s,
				 "reiserfs_parse_options: journalled quota format not specified.");
		return 0;
	}
	/* This checking is not precise wrt the quota type but for our purposes it is sufficient */
	if (!(*mount_options & (1 << REISERFS_QUOTA))
	    && sb_any_quota_enabled(s)) {
		reiserfs_warning(s,
				 "reiserfs_parse_options: quota options must be present when quota is turned on.");
		return 0;
	}
#endif

	return 1;
}

static void switch_data_mode(struct super_block *s, unsigned long mode)
{
	REISERFS_SB(s)->s_mount_opt &= ~((1 << REISERFS_DATA_LOG) |
					 (1 << REISERFS_DATA_ORDERED) |
					 (1 << REISERFS_DATA_WRITEBACK));
	REISERFS_SB(s)->s_mount_opt |= (1 << mode);
}

static void handle_data_mode(struct super_block *s, unsigned long mount_options)
{
	if (mount_options & (1 << REISERFS_DATA_LOG)) {
		if (!reiserfs_data_log(s)) {
			switch_data_mode(s, REISERFS_DATA_LOG);
			reiserfs_info(s, "switching to journaled data mode\n");
		}
	} else if (mount_options & (1 << REISERFS_DATA_ORDERED)) {
		if (!reiserfs_data_ordered(s)) {
			switch_data_mode(s, REISERFS_DATA_ORDERED);
			reiserfs_info(s, "switching to ordered data mode\n");
		}
	} else if (mount_options & (1 << REISERFS_DATA_WRITEBACK)) {
		if (!reiserfs_data_writeback(s)) {
			switch_data_mode(s, REISERFS_DATA_WRITEBACK);
			reiserfs_info(s, "switching to writeback data mode\n");
		}
	}
}

static void handle_barrier_mode(struct super_block *s, unsigned long bits)
{
	int flush = (1 << REISERFS_BARRIER_FLUSH);
	int none = (1 << REISERFS_BARRIER_NONE);
	int all_barrier = flush | none;

	if (bits & all_barrier) {
		REISERFS_SB(s)->s_mount_opt &= ~all_barrier;
		if (bits & flush) {
			REISERFS_SB(s)->s_mount_opt |= flush;
			printk("reiserfs: enabling write barrier flush mode\n");
		} else if (bits & none) {
			REISERFS_SB(s)->s_mount_opt |= none;
			printk("reiserfs: write barriers turned off\n");
		}
	}
}

static void handle_attrs(struct super_block *s)
{
	struct reiserfs_super_block *rs = SB_DISK_SUPER_BLOCK(s);

	if (reiserfs_attrs(s)) {
		if (old_format_only(s)) {
			reiserfs_warning(s,
					 "reiserfs: cannot support attributes on 3.5.x disk format");
			REISERFS_SB(s)->s_mount_opt &= ~(1 << REISERFS_ATTRS);
			return;
		}
		if (!(le32_to_cpu(rs->s_flags) & reiserfs_attrs_cleared)) {
			reiserfs_warning(s,
					 "reiserfs: cannot support attributes until flag is set in super-block");
			REISERFS_SB(s)->s_mount_opt &= ~(1 << REISERFS_ATTRS);
		}
	}
}

static int reiserfs_remount(struct super_block *s, int *mount_flags, char *arg)
{
	struct reiserfs_super_block *rs;
	struct reiserfs_transaction_handle th;
	unsigned long blocks;
	unsigned long mount_options = REISERFS_SB(s)->s_mount_opt;
	unsigned long safe_mask = 0;
	unsigned int commit_max_age = (unsigned int)-1;
	struct reiserfs_journal *journal = SB_JOURNAL(s);
	int err;
#ifdef CONFIG_QUOTA
	int i;
#endif

	rs = SB_DISK_SUPER_BLOCK(s);

	if (!reiserfs_parse_options
	    (s, arg, &mount_options, &blocks, NULL, &commit_max_age)) {
#ifdef CONFIG_QUOTA
		for (i = 0; i < MAXQUOTAS; i++) {
			kfree(REISERFS_SB(s)->s_qf_names[i]);
			REISERFS_SB(s)->s_qf_names[i] = NULL;
		}
#endif
		return -EINVAL;
	}

	handle_attrs(s);

	/* Add options that are safe here */
	safe_mask |= 1 << REISERFS_SMALLTAIL;
	safe_mask |= 1 << REISERFS_LARGETAIL;
	safe_mask |= 1 << REISERFS_NO_BORDER;
	safe_mask |= 1 << REISERFS_NO_UNHASHED_RELOCATION;
	safe_mask |= 1 << REISERFS_HASHED_RELOCATION;
	safe_mask |= 1 << REISERFS_TEST4;
	safe_mask |= 1 << REISERFS_ATTRS;
	safe_mask |= 1 << REISERFS_XATTRS_USER;
	safe_mask |= 1 << REISERFS_POSIXACL;
	safe_mask |= 1 << REISERFS_BARRIER_FLUSH;
	safe_mask |= 1 << REISERFS_BARRIER_NONE;
	safe_mask |= 1 << REISERFS_ERROR_RO;
	safe_mask |= 1 << REISERFS_ERROR_CONTINUE;
	safe_mask |= 1 << REISERFS_ERROR_PANIC;
	safe_mask |= 1 << REISERFS_QUOTA;

	/* Update the bitmask, taking care to keep
	 * the bits we're not allowed to change here */
	REISERFS_SB(s)->s_mount_opt =
	    (REISERFS_SB(s)->
	     s_mount_opt & ~safe_mask) | (mount_options & safe_mask);

	if (commit_max_age != 0 && commit_max_age != (unsigned int)-1) {
		journal->j_max_commit_age = commit_max_age;
		journal->j_max_trans_age = commit_max_age;
	} else if (commit_max_age == 0) {
		/* 0 means restore defaults. */
		journal->j_max_commit_age = journal->j_default_max_commit_age;
		journal->j_max_trans_age = JOURNAL_MAX_TRANS_AGE;
	}

	if (blocks) {
		int rc = reiserfs_resize(s, blocks);
		if (rc != 0)
			return rc;
	}

	if (*mount_flags & MS_RDONLY) {
		reiserfs_xattr_init(s, *mount_flags);
		/* remount read-only */
		if (s->s_flags & MS_RDONLY)
			/* it is read-only already */
			return 0;
		/* try to remount file system with read-only permissions */
		if (sb_umount_state(rs) == REISERFS_VALID_FS
		    || REISERFS_SB(s)->s_mount_state != REISERFS_VALID_FS) {
			return 0;
		}

		err = journal_begin(&th, s, 10);
		if (err)
			return err;

		/* Mounting a rw partition read-only. */
		reiserfs_prepare_for_journal(s, SB_BUFFER_WITH_SB(s), 1);
		set_sb_umount_state(rs, REISERFS_SB(s)->s_mount_state);
		journal_mark_dirty(&th, s, SB_BUFFER_WITH_SB(s));
	} else {
		/* remount read-write */
		if (!(s->s_flags & MS_RDONLY)) {
			reiserfs_xattr_init(s, *mount_flags);
			return 0;	/* We are read-write already */
		}

		if (reiserfs_is_journal_aborted(journal))
			return journal->j_errno;

		handle_data_mode(s, mount_options);
		handle_barrier_mode(s, mount_options);
		REISERFS_SB(s)->s_mount_state = sb_umount_state(rs);
		s->s_flags &= ~MS_RDONLY;	/* now it is safe to call journal_begin */
		err = journal_begin(&th, s, 10);
		if (err)
			return err;

		/* Mount a partition which is read-only, read-write */
		reiserfs_prepare_for_journal(s, SB_BUFFER_WITH_SB(s), 1);
		REISERFS_SB(s)->s_mount_state = sb_umount_state(rs);
		s->s_flags &= ~MS_RDONLY;
		set_sb_umount_state(rs, REISERFS_ERROR_FS);
		/* mark_buffer_dirty (SB_BUFFER_WITH_SB (s), 1); */
		journal_mark_dirty(&th, s, SB_BUFFER_WITH_SB(s));
		REISERFS_SB(s)->s_mount_state = REISERFS_VALID_FS;
	}
	/* this will force a full flush of all journal lists */
	SB_JOURNAL(s)->j_must_wait = 1;
	err = journal_end(&th, s, 10);
	if (err)
		return err;
	s->s_dirt = 0;

	if (!(*mount_flags & MS_RDONLY)) {
		finish_unfinished(s);
		reiserfs_xattr_init(s, *mount_flags);
	}

	return 0;
}

static int read_super_block(struct super_block *s, int offset)
{
	struct buffer_head *bh;
	struct reiserfs_super_block *rs;
	int fs_blocksize;

	bh = sb_bread(s, offset / s->s_blocksize);
	if (!bh) {
		reiserfs_warning(s, "sh-2006: read_super_block: "
				 "bread failed (dev %s, block %lu, size %lu)",
				 reiserfs_bdevname(s), offset / s->s_blocksize,
				 s->s_blocksize);
		return 1;
	}

	rs = (struct reiserfs_super_block *)bh->b_data;
	if (!is_any_reiserfs_magic_string(rs)) {
		brelse(bh);
		return 1;
	}
	//
	// ok, reiserfs signature (old or new) found in at the given offset
	//    
	fs_blocksize = sb_blocksize(rs);
	brelse(bh);
	sb_set_blocksize(s, fs_blocksize);

	bh = sb_bread(s, offset / s->s_blocksize);
	if (!bh) {
		reiserfs_warning(s, "sh-2007: read_super_block: "
				 "bread failed (dev %s, block %lu, size %lu)\n",
				 reiserfs_bdevname(s), offset / s->s_blocksize,
				 s->s_blocksize);
		return 1;
	}

	rs = (struct reiserfs_super_block *)bh->b_data;
	if (sb_blocksize(rs) != s->s_blocksize) {
		reiserfs_warning(s, "sh-2011: read_super_block: "
				 "can't find a reiserfs filesystem on (dev %s, block %Lu, size %lu)\n",
				 reiserfs_bdevname(s),
				 (unsigned long long)bh->b_blocknr,
				 s->s_blocksize);
		brelse(bh);
		return 1;
	}

	if (rs->s_v1.s_root_block == cpu_to_le32(-1)) {
		brelse(bh);
		reiserfs_warning(s,
				 "Unfinished reiserfsck --rebuild-tree run detected. Please run\n"
				 "reiserfsck --rebuild-tree and wait for a completion. If that fails\n"
				 "get newer reiserfsprogs package");
		return 1;
	}

	SB_BUFFER_WITH_SB(s) = bh;
	SB_DISK_SUPER_BLOCK(s) = rs;

	if (is_reiserfs_jr(rs)) {
		/* magic is of non-standard journal filesystem, look at s_version to
		   find which format is in use */
		if (sb_version(rs) == REISERFS_VERSION_2)
			reiserfs_warning(s,
					 "read_super_block: found reiserfs format \"3.6\""
					 " with non-standard journal");
		else if (sb_version(rs) == REISERFS_VERSION_1)
			reiserfs_warning(s,
					 "read_super_block: found reiserfs format \"3.5\""