Commit 740d9dcd authored by Mingming Cao's avatar Mingming Cao Committed by Jan Kara
Browse files

quota: Add quota reservation claim and released operations 



Reserved quota will be claimed at the block allocation time. Over-booked
quota could be returned back with the release callback function.

Signed-off-by: default avatarMingming Cao <cmm@us.ibm.com>
Signed-off-by: default avatarJan Kara <jack@suse.cz>
parent f18df228

fs/dquot.c

+106 −4
Original line number Diff line number Diff line
@@ -904,6 +904,23 @@ static inline void dquot_resv_space(struct dquot *dquot, qsize_t number) 
	dquot->dq_dqb.dqb_rsvspace += number;

}



/*

 * Claim reserved quota space

 */

static void dquot_claim_reserved_space(struct dquot *dquot,

						qsize_t number)

{

	WARN_ON(dquot->dq_dqb.dqb_rsvspace < number);

	dquot->dq_dqb.dqb_curspace += number;

	dquot->dq_dqb.dqb_rsvspace -= number;

}



static inline

void dquot_free_reserved_space(struct dquot *dquot, qsize_t number)

{

	dquot->dq_dqb.dqb_rsvspace -= number;

}



static inline void dquot_decr_inodes(struct dquot *dquot, qsize_t number)

{

	if (sb_dqopt(dquot->dq_sb)->flags & DQUOT_NEGATIVE_USAGE ||
@@ -1452,6 +1469,72 @@ int dquot_alloc_inode(const struct inode *inode, qsize_t number) 
	return ret;

}



int dquot_claim_space(struct inode *inode, qsize_t number)

{

	int cnt;

	int ret = QUOTA_OK;



	if (IS_NOQUOTA(inode)) {

		inode_add_bytes(inode, number);

		goto out;

	}



	down_read(&sb_dqopt(inode->i_sb)->dqptr_sem);

	if (IS_NOQUOTA(inode))	{

		up_read(&sb_dqopt(inode->i_sb)->dqptr_sem);

		inode_add_bytes(inode, number);

		goto out;

	}



	spin_lock(&dq_data_lock);

	/* Claim reserved quotas to allocated quotas */

	for (cnt = 0; cnt < MAXQUOTAS; cnt++) {

		if (inode->i_dquot[cnt] != NODQUOT)

			dquot_claim_reserved_space(inode->i_dquot[cnt],

							number);

	}

	/* Update inode bytes */

	inode_add_bytes(inode, number);

	spin_unlock(&dq_data_lock);

	/* Dirtify all the dquots - this can block when journalling */

	for (cnt = 0; cnt < MAXQUOTAS; cnt++)

		if (inode->i_dquot[cnt])

			mark_dquot_dirty(inode->i_dquot[cnt]);

	up_read(&sb_dqopt(inode->i_sb)->dqptr_sem);

out:

	return ret;

}

EXPORT_SYMBOL(dquot_claim_space);



/*

 * Release reserved quota space

 */

void dquot_release_reserved_space(struct inode *inode, qsize_t number)

{

	int cnt;



	if (IS_NOQUOTA(inode))

		goto out;



	down_read(&sb_dqopt(inode->i_sb)->dqptr_sem);

	if (IS_NOQUOTA(inode))

		goto out_unlock;



	spin_lock(&dq_data_lock);

	/* Release reserved dquots */

	for (cnt = 0; cnt < MAXQUOTAS; cnt++) {

		if (inode->i_dquot[cnt] != NODQUOT)

			dquot_free_reserved_space(inode->i_dquot[cnt], number);

	}

	spin_unlock(&dq_data_lock);



out_unlock:

	up_read(&sb_dqopt(inode->i_sb)->dqptr_sem);

out:

	return;

}

EXPORT_SYMBOL(dquot_release_reserved_space);



/*

 * This operation can block, but only after everything is updated

 */
@@ -1528,6 +1611,19 @@ int dquot_free_inode(const struct inode *inode, qsize_t number) 
	return QUOTA_OK;

}



/*

 * call back function, get reserved quota space from underlying fs

 */

qsize_t dquot_get_reserved_space(struct inode *inode)

{

	qsize_t reserved_space = 0;



	if (sb_any_quota_active(inode->i_sb) &&

	    inode->i_sb->dq_op->get_reserved_space)

		reserved_space = inode->i_sb->dq_op->get_reserved_space(inode);

	return reserved_space;

}



/*

 * Transfer the number of inode and blocks from one diskquota to an other.

 *
@@ -1536,7 +1632,8 @@ int dquot_free_inode(const struct inode *inode, qsize_t number) 
 */

int dquot_transfer(struct inode *inode, struct iattr *iattr)

{

	qsize_t space;

	qsize_t space, cur_space;

	qsize_t rsv_space = 0;

	struct dquot *transfer_from[MAXQUOTAS];

	struct dquot *transfer_to[MAXQUOTAS];

	int cnt, ret = QUOTA_OK;
@@ -1575,7 +1672,9 @@ int dquot_transfer(struct inode *inode, struct iattr *iattr) 
		goto put_all;

	}

	spin_lock(&dq_data_lock);

	space = inode_get_bytes(inode);

	cur_space = inode_get_bytes(inode);

	rsv_space = dquot_get_reserved_space(inode);

	space = cur_space + rsv_space;

	/* Build the transfer_from list and check the limits */

	for (cnt = 0; cnt < MAXQUOTAS; cnt++) {

		if (transfer_to[cnt] == NODQUOT)
@@ -1604,11 +1703,14 @@ int dquot_transfer(struct inode *inode, struct iattr *iattr) 
			warntype_from_space[cnt] =

				info_bdq_free(transfer_from[cnt], space);

			dquot_decr_inodes(transfer_from[cnt], 1);

			dquot_decr_space(transfer_from[cnt], space);

			dquot_decr_space(transfer_from[cnt], cur_space);

			dquot_free_reserved_space(transfer_from[cnt],

						  rsv_space);

		}



		dquot_incr_inodes(transfer_to[cnt], 1);

		dquot_incr_space(transfer_to[cnt], space);

		dquot_incr_space(transfer_to[cnt], cur_space);

		dquot_resv_space(transfer_to[cnt], rsv_space);



		inode->i_dquot[cnt] = transfer_to[cnt];

	}

include/linux/quota.h

+6 −0
Original line number Diff line number Diff line
@@ -311,6 +311,12 @@ struct dquot_operations { 
	int (*write_info) (struct super_block *, int);	/* Write of quota "superblock" */

	/* reserve quota for delayed block allocation */

	int (*reserve_space) (struct inode *, qsize_t, int);

	/* claim reserved quota for delayed alloc */

	int (*claim_space) (struct inode *, qsize_t);

	/* release rsved quota for delayed alloc */

	void (*release_rsv) (struct inode *, qsize_t);

	/* get reserved quota for delayed alloc */

	qsize_t (*get_reserved_space) (struct inode *);

};



/* Operations handling requests from userspace */

include/linux/quotaops.h

+53 −0
Original line number Diff line number Diff line
@@ -35,6 +35,11 @@ void dquot_destroy(struct dquot *dquot); 
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_reserve_space(struct inode *inode, qsize_t number, int prealloc);

int dquot_claim_space(struct inode *inode, qsize_t number);

void dquot_release_reserved_space(struct inode *inode, qsize_t number);

qsize_t dquot_get_reserved_space(struct inode *inode);



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

int dquot_free_inode(const struct inode *inode, qsize_t number);
@@ -203,6 +208,31 @@ static inline int vfs_dq_alloc_inode(struct inode *inode) 
	return 0;

}



/*

 * Convert in-memory reserved quotas to real consumed quotas

 */

static inline int vfs_dq_claim_space(struct inode *inode, qsize_t nr)

{

	if (sb_any_quota_active(inode->i_sb)) {

		if (inode->i_sb->dq_op->claim_space(inode, nr) == NO_QUOTA)

			return 1;

	} else

		inode_add_bytes(inode, nr);



	mark_inode_dirty(inode);

	return 0;

}



/*

 * Release reserved (in-memory) quotas

 */

static inline

void vfs_dq_release_reservation_space(struct inode *inode, qsize_t nr)

{

	if (sb_any_quota_active(inode->i_sb))

		inode->i_sb->dq_op->release_rsv(inode, nr);

}



static inline void vfs_dq_free_space_nodirty(struct inode *inode, qsize_t nr)

{

	if (sb_any_quota_active(inode->i_sb))
@@ -354,6 +384,17 @@ static inline int vfs_dq_reserve_space(struct inode *inode, qsize_t nr) 
	return 0;

}



static inline int vfs_dq_claim_space(struct inode *inode, qsize_t nr)

{

	return vfs_dq_alloc_space(inode, nr);

}



static inline

int vfs_dq_release_reservation_space(struct inode *inode, qsize_t nr)

{

	return 0;

}



static inline void vfs_dq_free_space_nodirty(struct inode *inode, qsize_t nr)

{

	inode_sub_bytes(inode, nr);
@@ -397,6 +438,18 @@ static inline int vfs_dq_reserve_block(struct inode *inode, qsize_t nr) 
			nr << inode->i_blkbits);

}



static inline int vfs_dq_claim_block(struct inode *inode, qsize_t nr)

{

	return vfs_dq_claim_space(inode,

			nr << inode->i_blkbits);

}



static inline

void vfs_dq_release_reservation_block(struct inode *inode, qsize_t nr)

{

	vfs_dq_release_reservation_space(inode, nr << inode->i_blkbits);

}



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);