super.c

linux 内核源代码

static void reiserfs_kill_sb(struct super_block *s)
{
	if (REISERFS_SB(s)) {
#ifdef CONFIG_REISERFS_FS_XATTR
		if (REISERFS_SB(s)->xattr_root) {
			d_invalidate(REISERFS_SB(s)->xattr_root);
			dput(REISERFS_SB(s)->xattr_root);
			REISERFS_SB(s)->xattr_root = NULL;
		}
#endif
		if (REISERFS_SB(s)->priv_root) {
			d_invalidate(REISERFS_SB(s)->priv_root);
			dput(REISERFS_SB(s)->priv_root);
			REISERFS_SB(s)->priv_root = NULL;
		}
	}

	kill_block_super(s);
}

static void reiserfs_put_super(struct super_block *s)
{
	struct reiserfs_transaction_handle th;
	th.t_trans_id = 0;

	/* change file system state to current state if it was mounted with read-write permissions */
	if (!(s->s_flags & MS_RDONLY)) {
		if (!journal_begin(&th, s, 10)) {
			reiserfs_prepare_for_journal(s, SB_BUFFER_WITH_SB(s),
						     1);
			set_sb_umount_state(SB_DISK_SUPER_BLOCK(s),
					    REISERFS_SB(s)->s_mount_state);
			journal_mark_dirty(&th, s, SB_BUFFER_WITH_SB(s));
		}
	}

	/* note, journal_release checks for readonly mount, and can decide not
	 ** to do a journal_end
	 */
	journal_release(&th, s);

	reiserfs_free_bitmap_cache(s);

	brelse(SB_BUFFER_WITH_SB(s));

	print_statistics(s);

	if (REISERFS_SB(s)->reserved_blocks != 0) {
		reiserfs_warning(s,
				 "green-2005: reiserfs_put_super: reserved blocks left %d",
				 REISERFS_SB(s)->reserved_blocks);
	}

	reiserfs_proc_info_done(s);

	kfree(s->s_fs_info);
	s->s_fs_info = NULL;

	return;
}

static struct kmem_cache *reiserfs_inode_cachep;

static struct inode *reiserfs_alloc_inode(struct super_block *sb)
{
	struct reiserfs_inode_info *ei;
	ei = (struct reiserfs_inode_info *)
	    kmem_cache_alloc(reiserfs_inode_cachep, GFP_KERNEL);
	if (!ei)
		return NULL;
	return &ei->vfs_inode;
}

static void reiserfs_destroy_inode(struct inode *inode)
{
	kmem_cache_free(reiserfs_inode_cachep, REISERFS_I(inode));
}

static void init_once(struct kmem_cache * cachep, void *foo)
{
	struct reiserfs_inode_info *ei = (struct reiserfs_inode_info *)foo;

	INIT_LIST_HEAD(&ei->i_prealloc_list);
	inode_init_once(&ei->vfs_inode);
#ifdef CONFIG_REISERFS_FS_POSIX_ACL
	ei->i_acl_access = NULL;
	ei->i_acl_default = NULL;
#endif
}

static int init_inodecache(void)
{
	reiserfs_inode_cachep = kmem_cache_create("reiser_inode_cache",
						  sizeof(struct
							 reiserfs_inode_info),
						  0, (SLAB_RECLAIM_ACCOUNT|
							SLAB_MEM_SPREAD),
						  init_once);
	if (reiserfs_inode_cachep == NULL)
		return -ENOMEM;
	return 0;
}

static void destroy_inodecache(void)
{
	kmem_cache_destroy(reiserfs_inode_cachep);
}

/* we don't mark inodes dirty, we just log them */
static void reiserfs_dirty_inode(struct inode *inode)
{
	struct reiserfs_transaction_handle th;

	int err = 0;
	if (inode->i_sb->s_flags & MS_RDONLY) {
		reiserfs_warning(inode->i_sb,
				 "clm-6006: writing inode %lu on readonly FS",
				 inode->i_ino);
		return;
	}
	reiserfs_write_lock(inode->i_sb);

	/* this is really only used for atime updates, so they don't have
	 ** to be included in O_SYNC or fsync
	 */
	err = journal_begin(&th, inode->i_sb, 1);
	if (err) {
		reiserfs_write_unlock(inode->i_sb);
		return;
	}
	reiserfs_update_sd(&th, inode);
	journal_end(&th, inode->i_sb, 1);
	reiserfs_write_unlock(inode->i_sb);
}

#ifdef CONFIG_REISERFS_FS_POSIX_ACL
static void reiserfs_clear_inode(struct inode *inode)
{
	struct posix_acl *acl;

	acl = REISERFS_I(inode)->i_acl_access;
	if (acl && !IS_ERR(acl))
		posix_acl_release(acl);
	REISERFS_I(inode)->i_acl_access = NULL;

	acl = REISERFS_I(inode)->i_acl_default;
	if (acl && !IS_ERR(acl))
		posix_acl_release(acl);
	REISERFS_I(inode)->i_acl_default = NULL;
}
#else
#define reiserfs_clear_inode NULL
#endif

#ifdef CONFIG_QUOTA
static ssize_t reiserfs_quota_write(struct super_block *, int, const char *,
				    size_t, loff_t);
static ssize_t reiserfs_quota_read(struct super_block *, int, char *, size_t,
				   loff_t);
#endif

static const struct super_operations reiserfs_sops = {
	.alloc_inode = reiserfs_alloc_inode,
	.destroy_inode = reiserfs_destroy_inode,
	.write_inode = reiserfs_write_inode,
	.dirty_inode = reiserfs_dirty_inode,
	.delete_inode = reiserfs_delete_inode,
	.clear_inode = reiserfs_clear_inode,
	.put_super = reiserfs_put_super,
	.write_super = reiserfs_write_super,
	.sync_fs = reiserfs_sync_fs,
	.write_super_lockfs = reiserfs_write_super_lockfs,
	.unlockfs = reiserfs_unlockfs,
	.statfs = reiserfs_statfs,
	.remount_fs = reiserfs_remount,
#ifdef CONFIG_QUOTA
	.quota_read = reiserfs_quota_read,
	.quota_write = reiserfs_quota_write,
#endif
};

#ifdef CONFIG_QUOTA
#define QTYPE2NAME(t) ((t)==USRQUOTA?"user":"group")

static int reiserfs_dquot_initialize(struct inode *, int);
static int reiserfs_dquot_drop(struct inode *);
static int reiserfs_write_dquot(struct dquot *);
static int reiserfs_acquire_dquot(struct dquot *);
static int reiserfs_release_dquot(struct dquot *);
static int reiserfs_mark_dquot_dirty(struct dquot *);
static int reiserfs_write_info(struct super_block *, int);
static int reiserfs_quota_on(struct super_block *, int, int, char *);

static struct dquot_operations reiserfs_quota_operations = {
	.initialize = reiserfs_dquot_initialize,
	.drop = reiserfs_dquot_drop,
	.alloc_space = dquot_alloc_space,
	.alloc_inode = dquot_alloc_inode,
	.free_space = dquot_free_space,
	.free_inode = dquot_free_inode,
	.transfer = dquot_transfer,
	.write_dquot = reiserfs_write_dquot,
	.acquire_dquot = reiserfs_acquire_dquot,
	.release_dquot = reiserfs_release_dquot,
	.mark_dirty = reiserfs_mark_dquot_dirty,
	.write_info = reiserfs_write_info,
};

static struct quotactl_ops reiserfs_qctl_operations = {
	.quota_on = reiserfs_quota_on,
	.quota_off = vfs_quota_off,
	.quota_sync = vfs_quota_sync,
	.get_info = vfs_get_dqinfo,
	.set_info = vfs_set_dqinfo,
	.get_dqblk = vfs_get_dqblk,
	.set_dqblk = vfs_set_dqblk,
};
#endif

static const struct export_operations reiserfs_export_ops = {
	.encode_fh = reiserfs_encode_fh,
	.fh_to_dentry = reiserfs_fh_to_dentry,
	.fh_to_parent = reiserfs_fh_to_parent,
	.get_parent = reiserfs_get_parent,
};

/* this struct is used in reiserfs_getopt () for containing the value for those
   mount options that have values rather than being toggles. */
typedef struct {
	char *value;
	int setmask;		/* bitmask which is to set on mount_options bitmask when this
				   value is found, 0 is no bits are to be changed. */
	int clrmask;		/* bitmask which is to clear on mount_options bitmask when  this
				   value is found, 0 is no bits are to be changed. This is
				   applied BEFORE setmask */
} arg_desc_t;

/* Set this bit in arg_required to allow empty arguments */
#define REISERFS_OPT_ALLOWEMPTY 31

/* this struct is used in reiserfs_getopt() for describing the set of reiserfs
   mount options */
typedef struct {
	char *option_name;
	int arg_required;	/* 0 if argument is not required, not 0 otherwise */
	const arg_desc_t *values;	/* list of values accepted by an option */
	int setmask;		/* bitmask which is to set on mount_options bitmask when this
				   value is found, 0 is no bits are to be changed. */
	int clrmask;		/* bitmask which is to clear on mount_options bitmask when  this
				   value is found, 0 is no bits are to be changed. This is
				   applied BEFORE setmask */
} opt_desc_t;

/* possible values for -o data= */
static const arg_desc_t logging_mode[] = {
	{"ordered", 1 << REISERFS_DATA_ORDERED,
	 (1 << REISERFS_DATA_LOG | 1 << REISERFS_DATA_WRITEBACK)},
	{"journal", 1 << REISERFS_DATA_LOG,
	 (1 << REISERFS_DATA_ORDERED | 1 << REISERFS_DATA_WRITEBACK)},
	{"writeback", 1 << REISERFS_DATA_WRITEBACK,
	 (1 << REISERFS_DATA_ORDERED | 1 << REISERFS_DATA_LOG)},
	{.value = NULL}
};

/* possible values for -o barrier= */
static const arg_desc_t barrier_mode[] = {
	{"none", 1 << REISERFS_BARRIER_NONE, 1 << REISERFS_BARRIER_FLUSH},
	{"flush", 1 << REISERFS_BARRIER_FLUSH, 1 << REISERFS_BARRIER_NONE},
	{.value = NULL}
};

/* possible values for "-o block-allocator=" and bits which are to be set in
   s_mount_opt of reiserfs specific part of in-core super block */
static const arg_desc_t balloc[] = {
	{"noborder", 1 << REISERFS_NO_BORDER, 0},
	{"border", 0, 1 << REISERFS_NO_BORDER},
	{"no_unhashed_relocation", 1 << REISERFS_NO_UNHASHED_RELOCATION, 0},
	{"hashed_relocation", 1 << REISERFS_HASHED_RELOCATION, 0},
	{"test4", 1 << REISERFS_TEST4, 0},
	{"notest4", 0, 1 << REISERFS_TEST4},
	{NULL, 0, 0}
};

static const arg_desc_t tails[] = {
	{"on", 1 << REISERFS_LARGETAIL, 1 << REISERFS_SMALLTAIL},
	{"off", 0, (1 << REISERFS_LARGETAIL) | (1 << REISERFS_SMALLTAIL)},
	{"small", 1 << REISERFS_SMALLTAIL, 1 << REISERFS_LARGETAIL},
	{NULL, 0, 0}
};

static const arg_desc_t error_actions[] = {
	{"panic", 1 << REISERFS_ERROR_PANIC,
	 (1 << REISERFS_ERROR_RO | 1 << REISERFS_ERROR_CONTINUE)},
	{"ro-remount", 1 << REISERFS_ERROR_RO,
	 (1 << REISERFS_ERROR_PANIC | 1 << REISERFS_ERROR_CONTINUE)},
#ifdef REISERFS_JOURNAL_ERROR_ALLOWS_NO_LOG
	{"continue", 1 << REISERFS_ERROR_CONTINUE,
	 (1 << REISERFS_ERROR_PANIC | 1 << REISERFS_ERROR_RO)},
#endif
	{NULL, 0, 0},
};

/* proceed only one option from a list *cur - string containing of mount options
   opts - array of options which are accepted
   opt_arg - if option is found and requires an argument and if it is specifed
   in the input - pointer to the argument is stored here
   bit_flags - if option requires to set a certain bit - it is set here
   return -1 if unknown option is found, opt->arg_required otherwise */
static int reiserfs_getopt(struct super_block *s, char **cur, opt_desc_t * opts,
			   char **opt_arg, unsigned long *bit_flags)
{
	char *p;
	/* foo=bar, 
	   ^   ^  ^
	   |   |  +-- option_end
	   |   +-- arg_start
	   +-- option_start
	 */
	const opt_desc_t *opt;
	const arg_desc_t *arg;

	p = *cur;

	/* assume argument cannot contain commas */
	*cur = strchr(p, ',');
	if (*cur) {
		*(*cur) = '\0';
		(*cur)++;
	}

	if (!strncmp(p, "alloc=", 6)) {
		/* Ugly special case, probably we should redo options parser so that
		   it can understand several arguments for some options, also so that
		   it can fill several bitfields with option values. */
		if (reiserfs_parse_alloc_options(s, p + 6)) {
			return -1;
		} else {
			return 0;
		}
	}

	/* for every option in the list */
	for (opt = opts; opt->option_name; opt++) {
		if (!strncmp(p, opt->option_name, strlen(opt->option_name))) {
			if (bit_flags) {
				if (opt->clrmask ==
				    (1 << REISERFS_UNSUPPORTED_OPT))
					reiserfs_warning(s, "%s not supported.",
							 p);
				else
					*bit_flags &= ~opt->clrmask;
				if (opt->setmask ==
				    (1 << REISERFS_UNSUPPORTED_OPT))
					reiserfs_warning(s, "%s not supported.",
							 p);
				else
					*bit_flags |= opt->setmask;
			}
			break;
		}
	}
	if (!opt->option_name) {
		reiserfs_warning(s, "unknown mount option \"%s\"", p);
		return -1;
	}

	p += strlen(opt->option_name);
	switch (*p) {
	case '=':
		if (!opt->arg_required) {
			reiserfs_warning(s,
					 "the option \"%s\" does not require an argument",
					 opt->option_name);
			return -1;
		}
		break;

	case 0:
		if (opt->arg_required) {
			reiserfs_warning(s,
					 "the option \"%s\" requires an argument",
					 opt->option_name);
			return -1;
		}
		break;
	default:
		reiserfs_warning(s, "head of option \"%s\" is only correct",
				 opt->option_name);
		return -1;
	}

	/* move to the argument, or to next option if argument is not required */
	p++;

	if (opt->arg_required
	    && !(opt->arg_required & (1 << REISERFS_OPT_ALLOWEMPTY))
	    && !strlen(p)) {
		/* this catches "option=," if not allowed */
		reiserfs_warning(s, "empty argument for \"%s\"",
				 opt->option_name);
		return -1;
	}

	if (!opt->values) {
		/* *=NULLopt_arg contains pointer to argument */
		*opt_arg = p;
		return opt->arg_required & ~(1 << REISERFS_OPT_ALLOWEMPTY);
	}

	/* values possible for this option are listed in opt->values */
	for (arg = opt->values; arg->value; arg++) {
		if (!strcmp(p, arg->value)) {
			if (bit_flags) {
				*bit_flags &= ~arg->clrmask;
				*bit_flags |= arg->setmask;
			}
			return opt->arg_required;
		}
	}

	reiserfs_warning(s, "bad value \"%s\" for option \"%s\"", p,
			 opt->option_name);
	return -1;
}

/* returns 0 if something is wrong in option string, 1 - otherwise */
static int reiserfs_parse_options(struct super_block *s, char *options,	/* string given via mount's -o */
				  unsigned long *mount_options,
				  /* after the parsing phase, contains the
				     collection of bitflags defining what
				     mount options were selected. */
				  unsigned long *blocks,	/* strtol-ed from NNN of resize=NNN */
				  char **jdev_name,
				  unsigned int *commit_max_age)
{
	int c;
	char *arg = NULL;
	char *pos;
	opt_desc_t opts[] = {
		/* Compatibility stuff, so that -o notail for old setups still work */
		{"tails",.arg_required = 't',.values = tails},
		{"notail",.clrmask =