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>

Documentation/filesystems/Locking

@@ -462,9 +462,7 @@ in sys_read() and friends.
 prototypes:
 	int (*initialize) (struct inode *, int);
 	int (*drop) (struct inode *);
-	int (*alloc_space) (struct inode *, qsize_t, int);
 	int (*alloc_inode) (const struct inode *, unsigned long);
-	int (*free_space) (struct inode *, qsize_t);
 	int (*free_inode) (const struct inode *, unsigned long);
 	int (*transfer) (struct inode *, struct iattr *);
 	int (*write_dquot) (struct dquot *);
@@ -481,9 +479,7 @@ What filesystem should expect from the generic quota functions:
 		FS recursion	Held locks when called
 initialize:	yes		maybe dqonoff_sem
 drop:		yes		-
-alloc_space:	->mark_dirty()	-
 alloc_inode:	->mark_dirty()	-
-free_space:	->mark_dirty()	-
 free_inode:	->mark_dirty()	-
 transfer:	yes		-
 write_dquot:	yes		dqonoff_sem or dqptr_sem
@@ -495,7 +491,7 @@ write_info:	yes		dqonoff_sem
 FS recursion means calling ->quota_read() and ->quota_write() from superblock
 operations.
 
-->alloc_space(), ->alloc_inode(), ->free_space(), ->free_inode() are called
+->alloc_inode(), ->free_inode() are called
 only directly by the filesystem and do not call any fs functions only
 the ->mark_dirty() operation.
 

fs/ext2/balloc.c

@@ -570,7 +570,7 @@ void ext2_free_blocks (struct inode * inode, unsigned long block,
 error_return:
 	brelse(bitmap_bh);
 	release_blocks(sb, freed);
-	vfs_dq_free_block(inode, freed);
+	dquot_free_block(inode, freed);
 }
 
 /**
@@ -1236,6 +1236,7 @@ ext2_fsblk_t ext2_new_blocks(struct inode *inode, ext2_fsblk_t goal,
 	unsigned short windowsz = 0;
 	unsigned long ngroups;
 	unsigned long num = *count;
+	int ret;
 
 	*errp = -ENOSPC;
 	sb = inode->i_sb;
@@ -1247,8 +1248,9 @@ ext2_fsblk_t ext2_new_blocks(struct inode *inode, ext2_fsblk_t goal,
 	/*
 	 * Check quota for allocation of this block.
 	 */
-	if (vfs_dq_alloc_block(inode, num)) {
-		*errp = -EDQUOT;
+	ret = dquot_alloc_block(inode, num);
+	if (ret) {
+		*errp = ret;
 		return 0;
 	}
 
@@ -1409,7 +1411,7 @@ ext2_fsblk_t ext2_new_blocks(struct inode *inode, ext2_fsblk_t goal,
 
 	*errp = 0;
 	brelse(bitmap_bh);
-	vfs_dq_free_block(inode, *count-num);
+	dquot_free_block(inode, *count-num);
 	*count = num;
 	return ret_block;
 
@@ -1420,7 +1422,7 @@ ext2_fsblk_t ext2_new_blocks(struct inode *inode, ext2_fsblk_t goal,
 	 * Undo the block allocation
 	 */
 	if (!performed_allocation)
-		vfs_dq_free_block(inode, *count);
+		dquot_free_block(inode, *count);
 	brelse(bitmap_bh);
 	return 0;
 }

fs/ext2/xattr.c

@@ -644,8 +644,8 @@ ext2_xattr_set2(struct inode *inode, struct buffer_head *old_bh,
 				   the inode.  */
 				ea_bdebug(new_bh, "reusing block");
 
-				error = -EDQUOT;
-				if (vfs_dq_alloc_block(inode, 1)) {
+				error = dquot_alloc_block(inode, 1);
+				if (error) {
 					unlock_buffer(new_bh);
 					goto cleanup;
 				}
@@ -702,7 +702,7 @@ ext2_xattr_set2(struct inode *inode, struct buffer_head *old_bh,
 		 * as if nothing happened and cleanup the unused block */
 		if (error && error != -ENOSPC) {
 			if (new_bh && new_bh != old_bh)
-				vfs_dq_free_block(inode, 1);
+				dquot_free_block(inode, 1);
 			goto cleanup;
 		}
 	} else
@@ -734,7 +734,7 @@ ext2_xattr_set2(struct inode *inode, struct buffer_head *old_bh,
 			le32_add_cpu(&HDR(old_bh)->h_refcount, -1);
 			if (ce)
 				mb_cache_entry_release(ce);
-			vfs_dq_free_block(inode, 1);
+			dquot_free_block(inode, 1);
 			mark_buffer_dirty(old_bh);
 			ea_bdebug(old_bh, "refcount now=%d",
 				le32_to_cpu(HDR(old_bh)->h_refcount));
@@ -797,7 +797,7 @@ ext2_xattr_delete_inode(struct inode *inode)
 		mark_buffer_dirty(bh);
 		if (IS_SYNC(inode))
 			sync_dirty_buffer(bh);
-		vfs_dq_free_block(inode, 1);
+		dquot_free_block(inode, 1);
 	}
 	EXT2_I(inode)->i_file_acl = 0;
 

fs/ext3/balloc.c

@@ -676,7 +676,7 @@ void ext3_free_blocks(handle_t *handle, struct inode *inode,
 	}
 	ext3_free_blocks_sb(handle, sb, block, count, &dquot_freed_blocks);
 	if (dquot_freed_blocks)
-		vfs_dq_free_block(inode, dquot_freed_blocks);
+		dquot_free_block(inode, dquot_freed_blocks);
 	return;
 }
 
@@ -1502,8 +1502,9 @@ ext3_fsblk_t ext3_new_blocks(handle_t *handle, struct inode *inode,
 	/*
 	 * Check quota for allocation of this block.
 	 */
-	if (vfs_dq_alloc_block(inode, num)) {
-		*errp = -EDQUOT;
+	err = dquot_alloc_block(inode, num);
+	if (err) {
+		*errp = err;
 		return 0;
 	}
 
@@ -1713,7 +1714,7 @@ ext3_fsblk_t ext3_new_blocks(handle_t *handle, struct inode *inode,
 
 	*errp = 0;
 	brelse(bitmap_bh);
-	vfs_dq_free_block(inode, *count-num);
+	dquot_free_block(inode, *count-num);
 	*count = num;
 	return ret_block;
 
@@ -1728,7 +1729,7 @@ ext3_fsblk_t ext3_new_blocks(handle_t *handle, struct inode *inode,
 	 * Undo the block allocation
 	 */
 	if (!performed_allocation)
-		vfs_dq_free_block(inode, *count);
+		dquot_free_block(inode, *count);
 	brelse(bitmap_bh);
 	return 0;
 }

fs/ext3/inode.c

@@ -3336,7 +3336,7 @@ int ext3_mark_inode_dirty(handle_t *handle, struct inode *inode)
  * i_size has been changed by generic_commit_write() and we thus need
  * to include the updated inode in the current transaction.
  *
- * Also, vfs_dq_alloc_space() will always dirty the inode when blocks
+ * Also, dquot_alloc_space() will always dirty the inode when blocks
  * are allocated to the file.
  *
  * If the inode is marked synchronous, we don't honour that here - doing

fs/ext3/super.c

@@ -752,9 +752,7 @@ static ssize_t ext3_quota_write(struct super_block *sb, int type,
 static const struct dquot_operations ext3_quota_operations = {
 	.initialize	= dquot_initialize,
 	.drop		= dquot_drop,
-	.alloc_space	= dquot_alloc_space,
 	.alloc_inode	= dquot_alloc_inode,
-	.free_space	= dquot_free_space,
 	.free_inode	= dquot_free_inode,
 	.transfer	= dquot_transfer,
 	.write_dquot	= ext3_write_dquot,

fs/ext3/xattr.c

@@ -500,7 +500,7 @@ ext3_xattr_release_block(handle_t *handle, struct inode *inode,
 		error = ext3_journal_dirty_metadata(handle, bh);
 		if (IS_SYNC(inode))
 			handle->h_sync = 1;
-		vfs_dq_free_block(inode, 1);
+		dquot_free_block(inode, 1);
 		ea_bdebug(bh, "refcount now=%d; releasing",
 			  le32_to_cpu(BHDR(bh)->h_refcount));
 		if (ce)
@@ -775,8 +775,8 @@ ext3_xattr_block_set(handle_t *handle, struct inode *inode,
 			else {
 				/* The old block is released after updating
 				   the inode. */
-				error = -EDQUOT;
-				if (vfs_dq_alloc_block(inode, 1))
+				error = dquot_alloc_block(inode, 1);
+				if (error)
 					goto cleanup;
 				error = ext3_journal_get_write_access(handle,
 								      new_bh);
@@ -850,7 +850,7 @@ ext3_xattr_block_set(handle_t *handle, struct inode *inode,
 	return error;
 
 cleanup_dquot:
-	vfs_dq_free_block(inode, 1);
+	dquot_free_block(inode, 1);
 	goto cleanup;
 
 bad_block:

fs/ext4/inode.c

@@ -1093,9 +1093,9 @@ void ext4_da_update_reserve_space(struct inode *inode,
 
 	/* Update quota subsystem */
 	if (quota_claim) {
-		vfs_dq_claim_block(inode, used);
+		dquot_claim_block(inode, used);
 		if (mdb_free)
-			vfs_dq_release_reservation_block(inode, mdb_free);
+			dquot_release_reservation_block(inode, mdb_free);
 	} else {
 		/*
 		 * We did fallocate with an offset that is already delayed
@@ -1106,8 +1106,8 @@ void ext4_da_update_reserve_space(struct inode *inode,
 		 * that
 		 */
 		if (allocated_meta_blocks)
-			vfs_dq_claim_block(inode, allocated_meta_blocks);
-		vfs_dq_release_reservation_block(inode, mdb_free + used);
+			dquot_claim_block(inode, allocated_meta_blocks);
+		dquot_release_reservation_block(inode, mdb_free + used);
 	}
 
 	/*
@@ -1836,6 +1836,7 @@ static int ext4_da_reserve_space(struct inode *inode, sector_t lblock)
 	struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
 	struct ext4_inode_info *ei = EXT4_I(inode);
 	unsigned long md_needed, md_reserved;
+	int ret;
 
 	/*
 	 * recalculate the amount of metadata blocks to reserve
@@ -1853,11 +1854,12 @@ static int ext4_da_reserve_space(struct inode *inode, sector_t lblock)
 	 * later. Real quota accounting is done at pages writeout
 	 * time.
 	 */
-	if (vfs_dq_reserve_block(inode, md_needed + 1))
-		return -EDQUOT;
+	ret = dquot_reserve_block(inode, md_needed + 1);
+	if (ret)
+		return ret;
 
 	if (ext4_claim_free_blocks(sbi, md_needed + 1)) {
-		vfs_dq_release_reservation_block(inode, md_needed + 1);
+		dquot_release_reservation_block(inode, md_needed + 1);
 		if (ext4_should_retry_alloc(inode->i_sb, &retries)) {
 			yield();
 			goto repeat;
@@ -1914,7 +1916,7 @@ static void ext4_da_release_space(struct inode *inode, int to_free)
 
 	spin_unlock(&EXT4_I(inode)->i_block_reservation_lock);
 
-	vfs_dq_release_reservation_block(inode, to_free);
+	dquot_release_reservation_block(inode, to_free);
 }
 
 static void ext4_da_page_release_reservation(struct page *page,
@@ -5641,7 +5643,7 @@ int ext4_mark_inode_dirty(handle_t *handle, struct inode *inode)
  * i_size has been changed by generic_commit_write() and we thus need
  * to include the updated inode in the current transaction.
  *
- * Also, vfs_dq_alloc_block() will always dirty the inode when blocks
+ * Also, dquot_alloc_block() will always dirty the inode when blocks
  * are allocated to the file.
  *
  * If the inode is marked synchronous, we don't honour that here - doing

fs/ext4/mballoc.c

@@ -4254,7 +4254,7 @@ ext4_fsblk_t ext4_mb_new_blocks(handle_t *handle,
 			return 0;
 		}
 		reserv_blks = ar->len;
-		while (ar->len && vfs_dq_alloc_block(ar->inode, ar->len)) {
+		while (ar->len && dquot_alloc_block(ar->inode, ar->len)) {
 			ar->flags |= EXT4_MB_HINT_NOPREALLOC;
 			ar->len--;
 		}
@@ -4331,7 +4331,7 @@ ext4_fsblk_t ext4_mb_new_blocks(handle_t *handle,
 	kmem_cache_free(ext4_ac_cachep, ac);
 out1:
 	if (inquota && ar->len < inquota)
-		vfs_dq_free_block(ar->inode, inquota - ar->len);
+		dquot_free_block(ar->inode, inquota - ar->len);
 out3:
 	if (!ar->len) {
 		if (!EXT4_I(ar->inode)->i_delalloc_reserved_flag)
@@ -4646,7 +4646,7 @@ void ext4_free_blocks(handle_t *handle, struct inode *inode,
 	sb->s_dirt = 1;
 error_return:
 	if (freed)
-		vfs_dq_free_block(inode, freed);
+		dquot_free_block(inode, freed);
 	brelse(bitmap_bh);
 	ext4_std_error(sb, err);
 	if (ac)

fs/ext4/super.c

@@ -1014,15 +1014,10 @@ static ssize_t ext4_quota_write(struct super_block *sb, int type,
 static const struct dquot_operations ext4_quota_operations = {
 	.initialize	= dquot_initialize,
 	.drop		= dquot_drop,
-	.alloc_space	= dquot_alloc_space,
-	.reserve_space	= dquot_reserve_space,
-	.claim_space	= dquot_claim_space,
-	.release_rsv	= dquot_release_reserved_space,
 #ifdef CONFIG_QUOTA
 	.get_reserved_space = ext4_get_reserved_space,
 #endif
 	.alloc_inode	= dquot_alloc_inode,
-	.free_space	= dquot_free_space,
 	.free_inode	= dquot_free_inode,
 	.transfer	= dquot_transfer,
 	.write_dquot	= ext4_write_dquot,

fs/ext4/xattr.c

@@ -494,7 +494,7 @@ ext4_xattr_release_block(handle_t *handle, struct inode *inode,
 		error = ext4_handle_dirty_metadata(handle, inode, bh);
 		if (IS_SYNC(inode))
 			ext4_handle_sync(handle);
-		vfs_dq_free_block(inode, 1);
+		dquot_free_block(inode, 1);
 		ea_bdebug(bh, "refcount now=%d; releasing",
 			  le32_to_cpu(BHDR(bh)->h_refcount));
 		if (ce)
@@ -787,8 +787,8 @@ ext4_xattr_block_set(handle_t *handle, struct inode *inode,
 			else {
 				/* The old block is released after updating
 				   the inode. */
-				error = -EDQUOT;
-				if (vfs_dq_alloc_block(inode, 1))
+				error = dquot_alloc_block(inode, 1);
+				if (error)
 					goto cleanup;
 				error = ext4_journal_get_write_access(handle,
 								      new_bh);
@@ -876,7 +876,7 @@ ext4_xattr_block_set(handle_t *handle, struct inode *inode,
 	return error;
 
 cleanup_dquot:
-	vfs_dq_free_block(inode, 1);
+	dquot_free_block(inode, 1);
 	goto cleanup;
 
 bad_block: