include/linux/quotaops.h

/*
 * Definitions for diskquota-operations. When diskquota is configured these
 * macros expand to the right source-code.
 *
 * Author:  Marco van Wieringen <mvw@planets.elm.net>
 */
#ifndef _LINUX_QUOTAOPS_
#define _LINUX_QUOTAOPS_

#include <linux/smp_lock.h>
#include <linux/fs.h>

static inline struct quota_info *sb_dqopt(struct super_block *sb)
{
	return &sb->s_dquot;
}

#if defined(CONFIG_QUOTA)

/*
 * declaration of quota_function calls in kernel.
 */
void sync_dquots(struct super_block *sb, int type);

int dquot_initialize(struct inode *inode, int type);
int dquot_drop(struct inode *inode);

int dquot_alloc_space(struct inode *inode, qsize_t number, int prealloc);
int dquot_alloc_inode(const struct inode *inode, qsize_t number);

int dquot_free_space(struct inode *inode, qsize_t number);
int dquot_free_inode(const struct inode *inode, qsize_t number);

int dquot_transfer(struct inode *inode, struct iattr *iattr);
int dquot_commit(struct dquot *dquot);
int dquot_acquire(struct dquot *dquot);
int dquot_release(struct dquot *dquot);
int dquot_commit_info(struct super_block *sb, int type);
int dquot_mark_dquot_dirty(struct dquot *dquot);

int vfs_quota_on(struct super_block *sb, int type, int format_id,
 	char *path, int remount);
int vfs_quota_on_path(struct super_block *sb, int type, int format_id,
 	struct path *path);
int vfs_quota_on_mount(struct super_block *sb, char *qf_name,
 	int format_id, int type);
int vfs_quota_off(struct super_block *sb, int type, int remount);
int vfs_quota_sync(struct super_block *sb, int type);
int vfs_get_dqinfo(struct super_block *sb, int type, struct if_dqinfo *ii);
int vfs_set_dqinfo(struct super_block *sb, int type, struct if_dqinfo *ii);
int vfs_get_dqblk(struct super_block *sb, int type, qid_t id, struct if_dqblk *di);
int vfs_set_dqblk(struct super_block *sb, int type, qid_t id, struct if_dqblk *di);

void vfs_dq_drop(struct inode *inode);
int vfs_dq_transfer(struct inode *inode, struct iattr *iattr);
int vfs_dq_quota_on_remount(struct super_block *sb);

static inline struct mem_dqinfo *sb_dqinfo(struct super_block *sb, int type)
{
	return sb_dqopt(sb)->info + type;
}

/*
 * Functions for checking status of quota
 */

static inline int sb_has_quota_enabled(struct super_block *sb, int type)
{
	if (type == USRQUOTA)
		return sb_dqopt(sb)->flags & DQUOT_USR_ENABLED;
	return sb_dqopt(sb)->flags & DQUOT_GRP_ENABLED;
}

static inline int sb_any_quota_enabled(struct super_block *sb)
{
	return sb_has_quota_enabled(sb, USRQUOTA) ||
		sb_has_quota_enabled(sb, GRPQUOTA);
}

static inline int sb_has_quota_suspended(struct super_block *sb, int type)
{
	if (type == USRQUOTA)
		return sb_dqopt(sb)->flags & DQUOT_USR_SUSPENDED;
	return sb_dqopt(sb)->flags & DQUOT_GRP_SUSPENDED;
}

static inline int sb_any_quota_suspended(struct super_block *sb)
{
	return sb_has_quota_suspended(sb, USRQUOTA) ||
		sb_has_quota_suspended(sb, GRPQUOTA);
}

/*
 * Operations supported for diskquotas.
 */
extern struct dquot_operations dquot_operations;
extern struct quotactl_ops vfs_quotactl_ops;

#define sb_dquot_ops (&dquot_operations)
#define sb_quotactl_ops (&vfs_quotactl_ops)

/* It is better to call this function outside of any transaction as it might
 * need a lot of space in journal for dquot structure allocation. */
static inline void vfs_dq_init(struct inode *inode)
{
	BUG_ON(!inode->i_sb);
	if (sb_any_quota_enabled(inode->i_sb) && !IS_NOQUOTA(inode))
		inode->i_sb->dq_op->initialize(inode, -1);
}

/* The following allocation/freeing/transfer functions *must* be called inside
 * a transaction (deadlocks possible otherwise) */
static inline int vfs_dq_prealloc_space_nodirty(struct inode *inode, qsize_t nr)
{
	if (sb_any_quota_enabled(inode->i_sb)) {
		/* Used space is updated in alloc_space() */
		if (inode->i_sb->dq_op->alloc_space(inode, nr, 1) == NO_QUOTA)
			return 1;
	}
	else
		inode_add_bytes(inode, nr);
	return 0;
}

static inline int vfs_dq_prealloc_space(struct inode *inode, qsize_t nr)
{
	int ret;
        if (!(ret =  vfs_dq_prealloc_space_nodirty(inode, nr)))
		mark_inode_dirty(inode);
	return ret;
}

static inline int vfs_dq_alloc_space_nodirty(struct inode *inode, qsize_t nr)
{
	if (sb_any_quota_enabled(inode->i_sb)) {
		/* Used space is updated in alloc_space() */
		if (inode->i_sb->dq_op->alloc_space(inode, nr, 0) == NO_QUOTA)
			return 1;
	}
	else
		inode_add_bytes(inode, nr);
	return 0;
}

static inline int vfs_dq_alloc_space(struct inode *inode, qsize_t nr)
{
	int ret;
	if (!(ret = vfs_dq_alloc_space_nodirty(inode, nr)))
		mark_inode_dirty(inode);
	return ret;
}

static inline int vfs_dq_alloc_inode(struct inode *inode)
{
	if (sb_any_quota_enabled(inode->i_sb)) {
		vfs_dq_init(inode);
		if (inode->i_sb->dq_op->alloc_inode(inode, 1) == NO_QUOTA)
			return 1;
	}
	return 0;
}

static inline void vfs_dq_free_space_nodirty(struct inode *inode, qsize_t nr)
{
	if (sb_any_quota_enabled(inode->i_sb))
		inode->i_sb->dq_op->free_space(inode, nr);
	else
		inode_sub_bytes(inode, nr);
}

static inline void vfs_dq_free_space(struct inode *inode, qsize_t nr)
{
	vfs_dq_free_space_nodirty(inode, nr);
	mark_inode_dirty(inode);
}

static inline void vfs_dq_free_inode(struct inode *inode)
{
	if (sb_any_quota_enabled(inode->i_sb))
		inode->i_sb->dq_op->free_inode(inode, 1);
}

/* The following two functions cannot be called inside a transaction */
static inline void vfs_dq_sync(struct super_block *sb)
{
	sync_dquots(sb, -1);
}

static inline int vfs_dq_off(struct super_block *sb, int remount)
{
	int ret = -ENOSYS;

	if (sb->s_qcop && sb->s_qcop->quota_off)
		ret = sb->s_qcop->quota_off(sb, -1, remount);
	return ret;
}

#else

static inline int sb_has_quota_enabled(struct super_block *sb, int type)
{
	return 0;
}

static inline int sb_any_quota_enabled(struct super_block *sb)
{
	return 0;
}

static inline int sb_has_quota_suspended(struct super_block *sb, int type)
{
	return 0;
}

static inline int sb_any_quota_suspended(struct super_block *sb)
{
	return 0;
}

/*
 * NO-OP when quota not configured.
 */
#define sb_dquot_ops				(NULL)
#define sb_quotactl_ops				(NULL)

static inline void vfs_dq_init(struct inode *inode)
{
}

static inline void vfs_dq_drop(struct inode *inode)
{
}

static inline int vfs_dq_alloc_inode(struct inode *inode)
{
	return 0;
}

static inline void vfs_dq_free_inode(struct inode *inode)
{
}

static inline void vfs_dq_sync(struct super_block *sb)
{
}

static inline int vfs_dq_off(struct super_block *sb, int remount)
{
	return 0;
}

static inline int vfs_dq_quota_on_remount(struct super_block *sb)
{
	return 0;
}

static inline int vfs_dq_transfer(struct inode *inode, struct iattr *iattr)
{
	return 0;
}

static inline int vfs_dq_prealloc_space_nodirty(struct inode *inode, qsize_t nr)
{
	inode_add_bytes(inode, nr);
	return 0;
}

static inline int vfs_dq_prealloc_space(struct inode *inode, qsize_t nr)
{
	vfs_dq_prealloc_space_nodirty(inode, nr);
	mark_inode_dirty(inode);
	return 0;
}

static inline int vfs_dq_alloc_space_nodirty(struct inode *inode, qsize_t nr)
{
	inode_add_bytes(inode, nr);
	return 0;
}

static inline int vfs_dq_alloc_space(struct inode *inode, qsize_t nr)
{
	vfs_dq_alloc_space_nodirty(inode, nr);
	mark_inode_dirty(inode);
	return 0;
}

static inline void vfs_dq_free_space_nodirty(struct inode *inode, qsize_t nr)
{
	inode_sub_bytes(inode, nr);
}

static inline void vfs_dq_free_space(struct inode *inode, qsize_t nr)
{
	vfs_dq_free_space_nodirty(inode, nr);
	mark_inode_dirty(inode);
}	

#endif /* CONFIG_QUOTA */

static inline int vfs_dq_prealloc_block_nodirty(struct inode *inode, qsize_t nr)
{
	return vfs_dq_prealloc_space_nodirty(inode,
			nr << inode->i_sb->s_blocksize_bits);
}

static inline int vfs_dq_prealloc_block(struct inode *inode, qsize_t nr)
{
	return vfs_dq_prealloc_space(inode,
			nr << inode->i_sb->s_blocksize_bits);
}

static inline int vfs_dq_alloc_block_nodirty(struct inode *inode, qsize_t nr)
{
 	return vfs_dq_alloc_space_nodirty(inode,
			nr << inode->i_sb->s_blocksize_bits);
}

static inline int vfs_dq_alloc_block(struct inode *inode, qsize_t nr)
{
	return vfs_dq_alloc_space(inode,
			nr << inode->i_sb->s_blocksize_bits);
}

static inline void vfs_dq_free_block_nodirty(struct inode *inode, qsize_t nr)
{
	vfs_dq_free_space_nodirty(inode, nr << inode->i_sb->s_blocksize_bits);
}

static inline void vfs_dq_free_block(struct inode *inode, qsize_t nr)
{
	vfs_dq_free_space(inode, nr << inode->i_sb->s_blocksize_bits);
}

/*
 * Define uppercase equivalents for compatibility with old function names
 * Can go away when we think all users have been converted (15/04/2008)
 */
#define DQUOT_INIT(inode) vfs_dq_init(inode)
#define DQUOT_DROP(inode) vfs_dq_drop(inode)
#define DQUOT_PREALLOC_SPACE_NODIRTY(inode, nr) \
				vfs_dq_prealloc_space_nodirty(inode, nr)
#define DQUOT_PREALLOC_SPACE(inode, nr) vfs_dq_prealloc_space(inode, nr)
#define DQUOT_ALLOC_SPACE_NODIRTY(inode, nr) \
				vfs_dq_alloc_space_nodirty(inode, nr)
#define DQUOT_ALLOC_SPACE(inode, nr) vfs_dq_alloc_space(inode, nr)
#define DQUOT_PREALLOC_BLOCK_NODIRTY(inode, nr) \
				vfs_dq_prealloc_block_nodirty(inode, nr)
#define DQUOT_PREALLOC_BLOCK(inode, nr) vfs_dq_prealloc_block(inode, nr)
#define DQUOT_ALLOC_BLOCK_NODIRTY(inode, nr) \
				vfs_dq_alloc_block_nodirty(inode, nr)
#define DQUOT_ALLOC_BLOCK(inode, nr) vfs_dq_alloc_block(inode, nr)
#define DQUOT_ALLOC_INODE(inode) vfs_dq_alloc_inode(inode)
#define DQUOT_FREE_SPACE_NODIRTY(inode, nr) \
				vfs_dq_free_space_nodirty(inode, nr)
#define DQUOT_FREE_SPACE(inode, nr) vfs_dq_free_space(inode, nr)
#define DQUOT_FREE_BLOCK_NODIRTY(inode, nr) \
				vfs_dq_free_block_nodirty(inode, nr)
#define DQUOT_FREE_BLOCK(inode, nr) vfs_dq_free_block(inode, nr)
#define DQUOT_FREE_INODE(inode) vfs_dq_free_inode(inode)
#define DQUOT_TRANSFER(inode, iattr) vfs_dq_transfer(inode, iattr)
#define DQUOT_SYNC(sb) vfs_dq_sync(sb)
#define DQUOT_OFF(sb, remount) vfs_dq_off(sb, remount)
#define DQUOT_ON_REMOUNT(sb) vfs_dq_quota_on_remount(sb)

#endif /* _LINUX_QUOTAOPS_ */