dquot: cleanup space allocation / freeing routines

Get rid of the alloc_space, free_space, reserve_space, claim_space and
release_rsv dquot operations - they are always called from the filesystem
and if a filesystem really needs their own (which none currently does)
it can just call into it's own routine directly.

Move shared logic into the common __dquot_alloc_space,
dquot_claim_space_nodirty and __dquot_free_space low-level methods,
and rationalize the wrappers around it to move as much as possible
code into the common block for CONFIG_QUOTA vs not.  Also rename
all these helpers to be named dquot_* instead of vfs_dq_*.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jan Kara <jack@suse.cz>
diff --git a/fs/jfs/jfs_dtree.c b/fs/jfs/jfs_dtree.c
index 925871e..0e4623b 100644
--- a/fs/jfs/jfs_dtree.c
+++ b/fs/jfs/jfs_dtree.c
@@ -381,10 +381,10 @@
 		 * It's time to move the inline table to an external
 		 * page and begin to build the xtree
 		 */
-		if (vfs_dq_alloc_block(ip, sbi->nbperpage))
+		if (dquot_alloc_block(ip, sbi->nbperpage))
 			goto clean_up;
 		if (dbAlloc(ip, 0, sbi->nbperpage, &xaddr)) {
-			vfs_dq_free_block(ip, sbi->nbperpage);
+			dquot_free_block(ip, sbi->nbperpage);
 			goto clean_up;
 		}
 
@@ -408,7 +408,7 @@
 			memcpy(&jfs_ip->i_dirtable, temp_table,
 			       sizeof (temp_table));
 			dbFree(ip, xaddr, sbi->nbperpage);
-			vfs_dq_free_block(ip, sbi->nbperpage);
+			dquot_free_block(ip, sbi->nbperpage);
 			goto clean_up;
 		}
 		ip->i_size = PSIZE;
@@ -1027,10 +1027,9 @@
 			n = xlen;
 
 		/* Allocate blocks to quota. */
-		if (vfs_dq_alloc_block(ip, n)) {
-			rc = -EDQUOT;
+		rc = dquot_alloc_block(ip, n);
+		if (rc)
 			goto extendOut;
-		}
 		quota_allocation += n;
 
 		if ((rc = dbReAlloc(sbi->ipbmap, xaddr, (s64) xlen,
@@ -1308,7 +1307,7 @@
 
 	/* Rollback quota allocation */
 	if (rc && quota_allocation)
-		vfs_dq_free_block(ip, quota_allocation);
+		dquot_free_block(ip, quota_allocation);
 
       dtSplitUp_Exit:
 
@@ -1369,9 +1368,10 @@
 		return -EIO;
 
 	/* Allocate blocks to quota. */
-	if (vfs_dq_alloc_block(ip, lengthPXD(pxd))) {
+	rc = dquot_alloc_block(ip, lengthPXD(pxd));
+	if (rc) {
 		release_metapage(rmp);
-		return -EDQUOT;
+		return rc;
 	}
 
 	jfs_info("dtSplitPage: ip:0x%p smp:0x%p rmp:0x%p", ip, smp, rmp);
@@ -1892,6 +1892,7 @@
 	struct dt_lock *dtlck;
 	struct tlock *tlck;
 	struct lv *lv;
+	int rc;
 
 	/* get split root page */
 	smp = split->mp;
@@ -1916,9 +1917,10 @@
 	rp = rmp->data;
 
 	/* Allocate blocks to quota. */
-	if (vfs_dq_alloc_block(ip, lengthPXD(pxd))) {
+	rc = dquot_alloc_block(ip, lengthPXD(pxd));
+	if (rc) {
 		release_metapage(rmp);
-		return -EDQUOT;
+		return rc;
 	}
 
 	BT_MARK_DIRTY(rmp, ip);
@@ -2287,7 +2289,7 @@
 	xlen = lengthPXD(&fp->header.self);
 
 	/* Free quota allocation. */
-	vfs_dq_free_block(ip, xlen);
+	dquot_free_block(ip, xlen);
 
 	/* free/invalidate its buffer page */
 	discard_metapage(fmp);
@@ -2363,7 +2365,7 @@
 				xlen = lengthPXD(&p->header.self);
 
 				/* Free quota allocation */
-				vfs_dq_free_block(ip, xlen);
+				dquot_free_block(ip, xlen);
 
 				/* free/invalidate its buffer page */
 				discard_metapage(mp);
diff --git a/fs/jfs/jfs_extent.c b/fs/jfs/jfs_extent.c
index 41d6045..5d3bbd1 100644
--- a/fs/jfs/jfs_extent.c
+++ b/fs/jfs/jfs_extent.c
@@ -141,10 +141,11 @@
 	}
 
 	/* Allocate blocks to quota. */
-	if (vfs_dq_alloc_block(ip, nxlen)) {
+	rc = dquot_alloc_block(ip, nxlen);
+	if (rc) {
 		dbFree(ip, nxaddr, (s64) nxlen);
 		mutex_unlock(&JFS_IP(ip)->commit_mutex);
-		return -EDQUOT;
+		return rc;
 	}
 
 	/* determine the value of the extent flag */
@@ -164,7 +165,7 @@
 	 */
 	if (rc) {
 		dbFree(ip, nxaddr, nxlen);
-		vfs_dq_free_block(ip, nxlen);
+		dquot_free_block(ip, nxlen);
 		mutex_unlock(&JFS_IP(ip)->commit_mutex);
 		return (rc);
 	}
@@ -256,10 +257,11 @@
 		goto exit;
 
 	/* Allocat blocks to quota. */
-	if (vfs_dq_alloc_block(ip, nxlen)) {
+	rc = dquot_alloc_block(ip, nxlen);
+	if (rc) {
 		dbFree(ip, nxaddr, (s64) nxlen);
 		mutex_unlock(&JFS_IP(ip)->commit_mutex);
-		return -EDQUOT;
+		return rc;
 	}
 
 	delta = nxlen - xlen;
@@ -297,7 +299,7 @@
 		/* extend the extent */
 		if ((rc = xtExtend(0, ip, xoff + xlen, (int) nextend, 0))) {
 			dbFree(ip, xaddr + xlen, delta);
-			vfs_dq_free_block(ip, nxlen);
+			dquot_free_block(ip, nxlen);
 			goto exit;
 		}
 	} else {
@@ -308,7 +310,7 @@
 		 */
 		if ((rc = xtTailgate(0, ip, xoff, (int) ntail, nxaddr, 0))) {
 			dbFree(ip, nxaddr, nxlen);
-			vfs_dq_free_block(ip, nxlen);
+			dquot_free_block(ip, nxlen);
 			goto exit;
 		}
 	}
diff --git a/fs/jfs/jfs_xtree.c b/fs/jfs/jfs_xtree.c
index d654a64..6c50871 100644
--- a/fs/jfs/jfs_xtree.c
+++ b/fs/jfs/jfs_xtree.c
@@ -585,10 +585,10 @@
 			hint = addressXAD(xad) + lengthXAD(xad) - 1;
 		} else
 			hint = 0;
-		if ((rc = vfs_dq_alloc_block(ip, xlen)))
+		if ((rc = dquot_alloc_block(ip, xlen)))
 			goto out;
 		if ((rc = dbAlloc(ip, hint, (s64) xlen, &xaddr))) {
-			vfs_dq_free_block(ip, xlen);
+			dquot_free_block(ip, xlen);
 			goto out;
 		}
 	}
@@ -617,7 +617,7 @@
 			/* undo data extent allocation */
 			if (*xaddrp == 0) {
 				dbFree(ip, xaddr, (s64) xlen);
-				vfs_dq_free_block(ip, xlen);
+				dquot_free_block(ip, xlen);
 			}
 			return rc;
 		}
@@ -985,10 +985,9 @@
 	rbn = addressPXD(pxd);
 
 	/* Allocate blocks to quota. */
-	if (vfs_dq_alloc_block(ip, lengthPXD(pxd))) {
-		rc = -EDQUOT;
+	rc = dquot_alloc_block(ip, lengthPXD(pxd));
+	if (rc)
 		goto clean_up;
-	}
 
 	quota_allocation += lengthPXD(pxd);
 
@@ -1195,7 +1194,7 @@
 
 	/* Rollback quota allocation. */
 	if (quota_allocation)
-		vfs_dq_free_block(ip, quota_allocation);
+		dquot_free_block(ip, quota_allocation);
 
 	return (rc);
 }
@@ -1235,6 +1234,7 @@
 	struct pxdlist *pxdlist;
 	struct tlock *tlck;
 	struct xtlock *xtlck;
+	int rc;
 
 	sp = &JFS_IP(ip)->i_xtroot;
 
@@ -1252,9 +1252,10 @@
 		return -EIO;
 
 	/* Allocate blocks to quota. */
-	if (vfs_dq_alloc_block(ip, lengthPXD(pxd))) {
+	rc = dquot_alloc_block(ip, lengthPXD(pxd));
+	if (rc) {
 		release_metapage(rmp);
-		return -EDQUOT;
+		return rc;
 	}
 
 	jfs_info("xtSplitRoot: ip:0x%p rmp:0x%p", ip, rmp);
@@ -3680,7 +3681,7 @@
 		ip->i_size = newsize;
 
 	/* update quota allocation to reflect freed blocks */
-	vfs_dq_free_block(ip, nfreed);
+	dquot_free_block(ip, nfreed);
 
 	/*
 	 * free tlock of invalidated pages
diff --git a/fs/jfs/xattr.c b/fs/jfs/xattr.c
index fad3645..1f594ab 100644
--- a/fs/jfs/xattr.c
+++ b/fs/jfs/xattr.c
@@ -260,14 +260,14 @@
 	nblocks = (size + (sb->s_blocksize - 1)) >> sb->s_blocksize_bits;
 
 	/* Allocate new blocks to quota. */
-	if (vfs_dq_alloc_block(ip, nblocks)) {
-		return -EDQUOT;
-	}
+	rc = dquot_alloc_block(ip, nblocks);
+	if (rc)
+		return rc;
 
 	rc = dbAlloc(ip, INOHINT(ip), nblocks, &blkno);
 	if (rc) {
 		/*Rollback quota allocation. */
-		vfs_dq_free_block(ip, nblocks);
+		dquot_free_block(ip, nblocks);
 		return rc;
 	}
 
@@ -332,7 +332,7 @@
 
       failed:
 	/* Rollback quota allocation. */
-	vfs_dq_free_block(ip, nblocks);
+	dquot_free_block(ip, nblocks);
 
 	dbFree(ip, blkno, nblocks);
 	return rc;
@@ -538,7 +538,8 @@
 
 	if (blocks_needed > current_blocks) {
 		/* Allocate new blocks to quota. */
-		if (vfs_dq_alloc_block(inode, blocks_needed))
+		rc = dquot_alloc_block(inode, blocks_needed);
+		if (rc)
 			return -EDQUOT;
 
 		quota_allocation = blocks_needed;
@@ -602,7 +603,7 @@
       clean_up:
 	/* Rollback quota allocation */
 	if (quota_allocation)
-		vfs_dq_free_block(inode, quota_allocation);
+		dquot_free_block(inode, quota_allocation);
 
 	return (rc);
 }
@@ -677,7 +678,7 @@
 
 	/* If old blocks exist, they must be removed from quota allocation. */
 	if (old_blocks)
-		vfs_dq_free_block(inode, old_blocks);
+		dquot_free_block(inode, old_blocks);
 
 	inode->i_ctime = CURRENT_TIME;