diff mbox

[V3,2/3] quota: Add quota claim and release reserved quota

Message ID 1229113616.7646.9.camel@mingming-laptop
State Not Applicable, archived
Headers show

Commit Message

Mingming Cao Dec. 12, 2008, 8:26 p.m. UTC 
在 2008-12-03三的 20:06 +0100，Jan Kara写道：
> Hmm, I can't find the email with this patch so I've just copied it from
> some mail archive ;). Sorry if the CC's are wrong.
> 
> > 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>
> > ---
> >  fs/dquot.c               |   87 +++++++++++++++++++++++++++++++++++++++++++++++
> >  include/linux/quota.h    |    4 +-
> >  include/linux/quotaops.h |   55 +++++++++++++++++++++++++++++
> >  3 files changed, 145 insertions(+), 1 deletion(-)
> > 
> > Index: linux-2.6.28-rc2/include/linux/quota.h
> > ===================================================================
> > --- linux-2.6.28-rc2.orig/include/linux/quota.h	2008-11-06 13:36:42.000000000 -0800
> > +++ linux-2.6.28-rc2/include/linux/quota.h	2008-11-06 14:03:52.000000000 -0800
> > @@ -292,7 +292,9 @@ struct dquot_operations {
> >  	int (*release_dquot) (struct dquot *);		/* Quota is going to be deleted from disk */
> >  	int (*mark_dirty) (struct dquot *);		/* Dquot is marked dirty */
> >  	int (*write_info) (struct super_block *, int);	/* Write of quota "superblock" */
> > -	int (*reserve_space) (struct inode *, qsize_t, int); /* reserve quota for delayed block allocation */
> > +	int (*reserve_space) (struct inode *, qsize_t, int); /* reserve quota for delayed alloc */
> > +	int (*claim_space) (struct inode *, qsize_t); /* claim reserved quota for delayed alloc */
> > +	void (*release_rsv) (struct inode *, qsize_t); /* release rsved quota for delayed alloc */
> >  };
> >  
> >  /* Operations handling requests from userspace */
> > Index: linux-2.6.28-rc2/include/linux/quotaops.h
> > ===================================================================
> > --- linux-2.6.28-rc2.orig/include/linux/quotaops.h	2008-11-06 13:37:04.000000000 -0800
> > +++ linux-2.6.28-rc2/include/linux/quotaops.h	2008-11-06 14:03:52.000000000 -0800
> > @@ -28,6 +28,11 @@ 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_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);
> > +
> > +
> >  int dquot_free_space(struct inode *inode, qsize_t number);
> >  int dquot_free_inode(const struct inode *inode, qsize_t number);
> >  
> > @@ -196,6 +201,31 @@ static inline int vfs_dq_alloc_inode(str
> >  	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))
> > @@ -342,6 +372,17 @@ static inline int vfs_dq_reserve_space(s
> >  	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);
> > @@ -386,6 +427,18 @@ static inline int vfs_dq_reserve_block(s
> >  			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(struct inode *inode, qsize_t nr)
> > +{
> > +	vfs_dq_release_reservation_space(inode, nr << inode->i_blkbits);
> > +}
> > +
>   I guess the function should be called like vfs_dq_release_reservation_block().
> It's ugly long but we should not omit the "block" part. Maybe we could shorten
> reservation everywhere in function names to rsv?
> 
> >  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);
> > @@ -415,6 +468,8 @@ static inline void vfs_dq_free_block(str
> >  				vfs_dq_alloc_block_nodirty(inode, nr)
> >  #define DQUOT_ALLOC_BLOCK(inode, nr) vfs_dq_alloc_block(inode, nr)
> >  #define DQUOT_RESERVE_BLOCK(inode, nr) vfs_dq_reserve_block(inode, nr)
> > +#define DQUOT_CLAIM_BLOCK(inode, nr) vfs_dq_claim_block(inode, nr)
> > +#define DQUOT_RELEASE_RSV_BLOCK(inode, nr) vfs_dq_release_reservation(inode, nr)
>   Please call lowercase variants from ext4 and don't define these functions.
> 
> >  #define DQUOT_ALLOC_INODE(inode) vfs_dq_alloc_inode(inode)
> >  #define DQUOT_FREE_SPACE_NODIRTY(inode, nr) \
> >  				vfs_dq_free_space_nodirty(inode, nr)
> > Index: linux-2.6.28-rc2/fs/dquot.c
> > ===================================================================
> > --- linux-2.6.28-rc2.orig/fs/dquot.c	2008-11-06 13:37:04.000000000 -0800
> > +++ linux-2.6.28-rc2/fs/dquot.c	2008-11-06 14:03:52.000000000 -0800
> > @@ -846,6 +846,24 @@ static inline void dquot_resv_space(stru
> >  	dquot->dq_dqb.dqb_rsvspace += number;
> >  }
> >  
> > +/*
> > + * Claim reserved quota space
> > + */
> > +static int dquot_claim_reserved_space(struct dquot *dquot,
> > +						qsize_t number)
> > +{
> > +	if (dquot->dq_dqb.dqb_rsvspace < number) {
> > +		printk(KERN_WARNING "Reserved quota %llu is not enough for"
> > +			"request %llu bytes\n",
> > +			(unsigned long long)dquot->dq_dqb.dqb_rsvspace, number);
> > +		return 1;
>   Wouldn't a WARN_ON here be more appropriate? It's a filesystem bug to cause
> this AFAICS.
> 
> > +	}
> > +
> > +	dquot->dq_dqb.dqb_curspace += number;
> > +	dquot->dq_dqb.dqb_rsvspace -= number;
> > +	return 0;
> > +}
>   You should use dq_data_lock to protect these operations...
> 
> > +
> >  static inline void dquot_decr_inodes(struct dquot *dquot, qsize_t number)
> >  {
> >  	if (dquot->dq_dqb.dqb_curinodes > number)
> > @@ -1319,6 +1337,73 @@ out:
> >  	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);
> > +		return ret;
> > +	}
> > +
> > +	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);
> > +		return ret;
> > +	}
> > +
> > +	/* Claim reserved quotas to allocated quotas */
> > +	for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
> > +		if (inode->i_dquot[cnt] != NODQUOT)
> > +			ret = dquot_claim_reserved_space(inode->i_dquot[cnt],
> > +							number);
> > +	}
> > +	if (ret == NO_QUOTA) {
> > +		up_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
> > +		return ret;
> > +	}
>   It seems a bit silly to try to recover here from filesystem bugs. I'd just
> make dquot_claim_reserved_space() void and ignore possible failure here.
> We won't do anything harmful like loosing data. Just counters might become
> out of sync but given there's a bug in fs anyway it does not matter much.
> 
> > +	/* 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);
> > +
> > +	/* Update inode bytes */
> > +	inode_add_bytes(inode, number);
>   And this should be called from under dq_data_lock from
> dquot_claim_reserved_space().
>   BTW: This reminds me that you should also modify dquot_transfer() function.
> Because that should not only transfer i_blocks sectors from one user
> to another but it has to also transfer the amount reserved for that inode...
> I think the easiest way around this would be to change i_blocks already when
> reservation is acquired (and than substract it when some of it is given back).
> 
> > +	return ret;
> > +}
> > +
> > +/*
> > + * Release reserved quota space
> > + */
> > +void dquot_release_reserved_space(struct inode *inode, qsize_t number)
> > +{
> > +	int cnt;
> > +	struct dquot *dquot;
> > +
> > +	if (IS_NOQUOTA(inode))
> > +		goto out;
> > +
> > +	down_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
> > +	if (IS_NOQUOTA(inode))
> > +		goto out_unlock;
> > +
> > +	/* Release reserved dquots */
> > +	for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
> > +		if (inode->i_dquot[cnt] != NODQUOT) {
> > +			dquot = inode->i_dquot[cnt];
> > +			dquot->dq_dqb.dqb_rsvspace -= number;
> > +		}
> > +	}
>   Again dq_data_lock...
> 
> > +
> > +out_unlock:
> > +	up_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
> > +out:
> > +	return;
> > +}
> > +
> >  /*
> >   * This operation can block, but only after everything is updated
> >   */
> > @@ -2344,6 +2429,8 @@ EXPORT_SYMBOL(dquot_alloc_inode);
> >  EXPORT_SYMBOL(dquot_free_space);
> >  EXPORT_SYMBOL(dquot_free_inode);
> >  EXPORT_SYMBOL(dquot_reserve_space);
> > +EXPORT_SYMBOL(dquot_claim_space);
> > +EXPORT_SYMBOL(dquot_release_reserved_space);
> >  EXPORT_SYMBOL(dquot_transfer);
> >  EXPORT_SYMBOL(vfs_dq_transfer);
> >  EXPORT_SYMBOL(vfs_dq_quota_on_remount);
> 
> 										Honza

Incremental fix
---
 fs/dquot.c               |   54 ++++++++++++++++++++++++++---------------------
 include/linux/quotaops.h |    4 ---
 2 files changed, 31 insertions(+), 27 deletions(-)



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diff mbox

Patch

Index: linux-2.6.28-rc2/fs/dquot.c
===================================================================
--- linux-2.6.28-rc2.orig/fs/dquot.c	2008-12-09 15:56:29.000000000 -0800
+++ linux-2.6.28-rc2/fs/dquot.c	2008-12-09 17:09:14.000000000 -0800
@@ -849,19 +849,18 @@  static inline void dquot_resv_space(stru
 /*
  * Claim reserved quota space
  */
-static int dquot_claim_reserved_space(struct dquot *dquot,
+static void dquot_claim_reserved_space(struct dquot *dquot,
 						qsize_t number)
 {
-	if (dquot->dq_dqb.dqb_rsvspace < number) {
-		printk(KERN_WARNING "Reserved quota %llu is not enough for"
-			"request %llu bytes\n",
-			(unsigned long long)dquot->dq_dqb.dqb_rsvspace, number);
-		return 1;
-	}
-
+	WARN_ON(dquot->dq_dqb.dqb_rsvspace < number);
 	dquot->dq_dqb.dqb_curspace += number;
 	dquot->dq_dqb.dqb_rsvspace -= number;
-	return 0;
+}
+
+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)
@@ -1344,34 +1343,32 @@  int dquot_claim_space(struct inode *inod
 
 	if (IS_NOQUOTA(inode)) {
 		inode_add_bytes(inode, number);
-		return ret;
+		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);
-		return ret;
+		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)
-			ret = dquot_claim_reserved_space(inode->i_dquot[cnt],
+			dquot_claim_reserved_space(inode->i_dquot[cnt],
 							number);
 	}
-	if (ret == NO_QUOTA) {
-		up_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
-		return ret;
-	}
+	/* 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);
-
-	/* Update inode bytes */
-	inode_add_bytes(inode, number);
+out:
 	return ret;
 }
 
@@ -1390,13 +1387,15 @@  void dquot_release_reserved_space(struct
 	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 = inode->i_dquot[cnt];
-			dquot->dq_dqb.dqb_rsvspace -= number;
+			dquot_free_reserved_space(dquot, number);
 		}
 	}
+	spin_unlock(&dq_data_lock);
 
 out_unlock:
 	up_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
@@ -1533,7 +1532,8 @@  int dquot_free_inode(const struct inode 
  */
 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 = NO_QUOTA, chuid = (iattr->ia_valid & ATTR_UID) && inode->i_uid != iattr->ia_uid,
@@ -1574,12 +1574,16 @@  int dquot_transfer(struct inode *inode, 
 		}
 	}
 	spin_lock(&dq_data_lock);
-	space = inode_get_bytes(inode);
+	space = cur_space = inode_get_bytes(inode);
 	/* Build the transfer_from list and check the limits */
 	for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
 		if (transfer_to[cnt] == NODQUOT)
 			continue;
 		transfer_from[cnt] = inode->i_dquot[cnt];
+		if (!rsv_space) {
+			rsv_space = transfer_from[cnt]->dq_dqb.dqb_rsvspace;
+			space += rsv_space;
+		}
 		if (check_idq(transfer_to[cnt], 1, warntype_to + cnt) ==
 		    NO_QUOTA || check_bdq(transfer_to[cnt], space, 0,
 		    warntype_to + cnt) == NO_QUOTA)
@@ -1603,11 +1607,13 @@  int dquot_transfer(struct inode *inode, 
 			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];
 	}
Index: linux-2.6.28-rc2/include/linux/quotaops.h
===================================================================
--- linux-2.6.28-rc2.orig/include/linux/quotaops.h	2008-12-09 15:56:04.000000000 -0800
+++ linux-2.6.28-rc2/include/linux/quotaops.h	2008-12-09 15:58:09.000000000 -0800
@@ -434,7 +434,7 @@  static inline int vfs_dq_claim_block(str
 }
 
 static inline
-void vfs_dq_release_reservation(struct inode *inode, qsize_t nr)
+void vfs_dq_release_reservation_block(struct inode *inode, qsize_t nr)
 {
 	vfs_dq_release_reservation_space(inode, nr << inode->i_blkbits);
 }
@@ -467,8 +467,6 @@  static inline void vfs_dq_free_block(str
 #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_CLAIM_BLOCK(inode, nr) vfs_dq_claim_block(inode, nr)
-#define DQUOT_RELEASE_RSV_BLOCK(inode, nr) vfs_dq_release_reservation(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)