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: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: Jan Kara <jack@suse.cz>

diff --git a/fs/dquot.c b/fs/dquot.c
index 9b1c4d3c9d83dbb84bc2b3478ed9329ac7d2a8f6..2916f91ca40ccbba496b8d242bd758d987484ed2 100644 (file)
--- a/fs/dquot.c
+++ b/fs/dquot.c
@@ -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 @@ warn_put_all:
        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];
        }

diff --git a/include/linux/quota.h b/include/linux/quota.h
index 54b837fa64f2398752dd9cdef85cd3607ffda1d0..a510d91561f48f31568e3afc1c781daac22a0a21 100644 (file)
--- a/include/linux/quota.h
+++ b/include/linux/quota.h
@@ -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 */

diff --git a/include/linux/quotaops.h b/include/linux/quotaops.h
index 3e3a0d2874d986427ed21366cc0a49a9f28dcd7b..7369d04e0a864aef0d91eb8a57fc47ddf9253da8 100644 (file)
--- a/include/linux/quotaops.h
+++ b/include/linux/quotaops.h
@@ -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);