udf: Factor out code for creating indirect extent

Factor out code for creating indirect extent from udf_add_aext(). It was
mostly duplicated in two places. Also remove some opencoded versions
of udf_write_aext().
Signed-off-by: Jan Kara <jack@suse.cz>

fs/udf/balloc.c

@@ -447,9 +447,6 @@ static void udf_table_free_blocks(struct super_block *sb,
 		 */
 
 		int adsize;
-		struct short_ad *sad = NULL;
-		struct long_ad *lad = NULL;
-		struct allocExtDesc *aed;
 
 		eloc.logicalBlockNum = start;
 		elen = EXT_RECORDED_ALLOCATED |
@@ -466,102 +463,17 @@ static void udf_table_free_blocks(struct super_block *sb,
 		}
 
 		if (epos.offset + (2 * adsize) > sb->s_blocksize) {
-			unsigned char *sptr, *dptr;
-			int loffset;
-
-			brelse(oepos.bh);
-			oepos = epos;
-
 			/* Steal a block from the extent being free'd */
-			epos.block.logicalBlockNum = eloc.logicalBlockNum;
+			udf_setup_indirect_aext(table, eloc.logicalBlockNum,
+						&epos);
+
 			eloc.logicalBlockNum++;
 			elen -= sb->s_blocksize;
-
-			epos.bh = udf_tread(sb,
-					udf_get_lb_pblock(sb, &epos.block, 0));
-			if (!epos.bh) {
-				brelse(oepos.bh);
-				goto error_return;
-			}
-			aed = (struct allocExtDesc *)(epos.bh->b_data);
-			aed->previousAllocExtLocation =
-				cpu_to_le32(oepos.block.logicalBlockNum);
-			if (epos.offset + adsize > sb->s_blocksize) {
-				loffset = epos.offset;
-				aed->lengthAllocDescs = cpu_to_le32(adsize);
-				sptr = iinfo->i_ext.i_data + epos.offset
-								- adsize;
-				dptr = epos.bh->b_data +
-					sizeof(struct allocExtDesc);
-				memcpy(dptr, sptr, adsize);
-				epos.offset = sizeof(struct allocExtDesc) +
-						adsize;
-			} else {
-				loffset = epos.offset + adsize;
-				aed->lengthAllocDescs = cpu_to_le32(0);
-				if (oepos.bh) {
-					sptr = oepos.bh->b_data + epos.offset;
-					aed = (struct allocExtDesc *)
-						oepos.bh->b_data;
-					le32_add_cpu(&aed->lengthAllocDescs,
-							adsize);
-				} else {
-					sptr = iinfo->i_ext.i_data +
-								epos.offset;
-					iinfo->i_lenAlloc += adsize;
-					mark_inode_dirty(table);
-				}
-				epos.offset = sizeof(struct allocExtDesc);
-			}
-			if (sbi->s_udfrev >= 0x0200)
-				udf_new_tag(epos.bh->b_data, TAG_IDENT_AED,
-					    3, 1, epos.block.logicalBlockNum,
-					    sizeof(struct tag));
-			else
-				udf_new_tag(epos.bh->b_data, TAG_IDENT_AED,
-					    2, 1, epos.block.logicalBlockNum,
-					    sizeof(struct tag));
-
-			switch (iinfo->i_alloc_type) {
-			case ICBTAG_FLAG_AD_SHORT:
-				sad = (struct short_ad *)sptr;
-				sad->extLength = cpu_to_le32(
-					EXT_NEXT_EXTENT_ALLOCDECS |
-					sb->s_blocksize);
-				sad->extPosition =
-					cpu_to_le32(epos.block.logicalBlockNum);
-				break;
-			case ICBTAG_FLAG_AD_LONG:
-				lad = (struct long_ad *)sptr;
-				lad->extLength = cpu_to_le32(
-					EXT_NEXT_EXTENT_ALLOCDECS |
-					sb->s_blocksize);
-				lad->extLocation =
-					cpu_to_lelb(epos.block);
-				break;
-			}
-			if (oepos.bh) {
-				udf_update_tag(oepos.bh->b_data, loffset);
-				mark_buffer_dirty(oepos.bh);
-			} else {
-				mark_inode_dirty(table);
-			}
 		}
 
 		/* It's possible that stealing the block emptied the extent */
-		if (elen) {
-			udf_write_aext(table, &epos, &eloc, elen, 1);
-
-			if (!epos.bh) {
-				iinfo->i_lenAlloc += adsize;
-				mark_inode_dirty(table);
-			} else {
-				aed = (struct allocExtDesc *)epos.bh->b_data;
-				le32_add_cpu(&aed->lengthAllocDescs, adsize);
-				udf_update_tag(epos.bh->b_data, epos.offset);
-				mark_buffer_dirty(epos.bh);
-			}
-		}
+		if (elen)
+			__udf_add_aext(table, &epos, &eloc, elen, 1);
 	}
 
 	brelse(epos.bh);

fs/udf/inode.c

@@ -1866,112 +1866,102 @@ struct inode *__udf_iget(struct super_block *sb, struct kernel_lb_addr *ino,
 	return inode;
 }
 
-int udf_add_aext(struct inode *inode, struct extent_position *epos,
-		 struct kernel_lb_addr *eloc, uint32_t elen, int inc)
+int udf_setup_indirect_aext(struct inode *inode, int block,
+			    struct extent_position *epos)
 {
-	int adsize;
-	struct short_ad *sad = NULL;
-	struct long_ad *lad = NULL;
+	struct super_block *sb = inode->i_sb;
+	struct buffer_head *bh;
 	struct allocExtDesc *aed;
-	uint8_t *ptr;
-	struct udf_inode_info *iinfo = UDF_I(inode);
+	struct extent_position nepos;
+	struct kernel_lb_addr neloc;
+	int ver, adsize;
 
-	if (!epos->bh)
-		ptr = iinfo->i_ext.i_data + epos->offset -
-			udf_file_entry_alloc_offset(inode) +
-			iinfo->i_lenEAttr;
+	if (UDF_I(inode)->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
+		adsize = sizeof(struct short_ad);
+	else if (UDF_I(inode)->i_alloc_type == ICBTAG_FLAG_AD_LONG)
+		adsize = sizeof(struct long_ad);
+
+	neloc.logicalBlockNum = block;
+	neloc.partitionReferenceNum = epos->block.partitionReferenceNum;
+
+	bh = udf_tgetblk(sb, udf_get_lb_pblock(sb, &neloc, 0));
+	if (!bh)
+		return -EIO;
+	lock_buffer(bh);
+	memset(bh->b_data, 0x00, sb->s_blocksize);
+	set_buffer_uptodate(bh);
+	unlock_buffer(bh);
+	mark_buffer_dirty_inode(bh, inode);
+
+	aed = (struct allocExtDesc *)(bh->b_data);
+	if (!UDF_QUERY_FLAG(sb, UDF_FLAG_STRICT)) {
+		aed->previousAllocExtLocation =
+				cpu_to_le32(epos->block.logicalBlockNum);
+	}
+	aed->lengthAllocDescs = cpu_to_le32(0);
+	if (UDF_SB(sb)->s_udfrev >= 0x0200)
+		ver = 3;
 	else
-		ptr = epos->bh->b_data + epos->offset;
+		ver = 2;
+	udf_new_tag(bh->b_data, TAG_IDENT_AED, ver, 1, block,
+		    sizeof(struct tag));
+
+	nepos.block = neloc;
+	nepos.offset = sizeof(struct allocExtDesc);
+	nepos.bh = bh;
+
+	/*
+	 * Do we have to copy current last extent to make space for indirect
+	 * one?
+	 */
+	if (epos->offset + adsize > sb->s_blocksize) {
+		struct kernel_lb_addr cp_loc;
+		uint32_t cp_len;
+		int cp_type;
+
+		epos->offset -= adsize;
+		cp_type = udf_current_aext(inode, epos, &cp_loc, &cp_len, 0);
+		cp_len |= ((uint32_t)cp_type) << 30;
+
+		__udf_add_aext(inode, &nepos, &cp_loc, cp_len, 1);
+		udf_write_aext(inode, epos, &nepos.block,
+			       sb->s_blocksize | EXT_NEXT_EXTENT_ALLOCDECS, 0);
+	} else {
+		__udf_add_aext(inode, epos, &nepos.block,
+			       sb->s_blocksize | EXT_NEXT_EXTENT_ALLOCDECS, 0);
+	}
+
+	brelse(epos->bh);
+	*epos = nepos;
+
+	return 0;
+}
+
+/*
+ * Append extent at the given position - should be the first free one in inode
+ * / indirect extent. This function assumes there is enough space in the inode
+ * or indirect extent. Use udf_add_aext() if you didn't check for this before.
+ */
+int __udf_add_aext(struct inode *inode, struct extent_position *epos,
+		   struct kernel_lb_addr *eloc, uint32_t elen, int inc)
+{
+	struct udf_inode_info *iinfo = UDF_I(inode);
+	struct allocExtDesc *aed;
+	int adsize;
 
 	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
 		adsize = sizeof(struct short_ad);
 	else if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_LONG)
 		adsize = sizeof(struct long_ad);
-	else
-		return -EIO;
-
-	if (epos->offset + (2 * adsize) > inode->i_sb->s_blocksize) {
-		unsigned char *sptr, *dptr;
-		struct buffer_head *nbh;
-		int err, loffset;
-		struct kernel_lb_addr obloc = epos->block;
 
-		epos->block.logicalBlockNum = udf_new_block(inode->i_sb, NULL,
-						obloc.partitionReferenceNum,
-						obloc.logicalBlockNum, &err);
-		if (!epos->block.logicalBlockNum)
-			return -ENOSPC;
-		nbh = udf_tgetblk(inode->i_sb, udf_get_lb_pblock(inode->i_sb,
-								 &epos->block,
-								 0));
-		if (!nbh)
-			return -EIO;
-		lock_buffer(nbh);
-		memset(nbh->b_data, 0x00, inode->i_sb->s_blocksize);
-		set_buffer_uptodate(nbh);
-		unlock_buffer(nbh);
-		mark_buffer_dirty_inode(nbh, inode);
-
-		aed = (struct allocExtDesc *)(nbh->b_data);
-		if (!UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_STRICT))
-			aed->previousAllocExtLocation =
-					cpu_to_le32(obloc.logicalBlockNum);
-		if (epos->offset + adsize > inode->i_sb->s_blocksize) {
-			loffset = epos->offset;
-			aed->lengthAllocDescs = cpu_to_le32(adsize);
-			sptr = ptr - adsize;
-			dptr = nbh->b_data + sizeof(struct allocExtDesc);
-			memcpy(dptr, sptr, adsize);
-			epos->offset = sizeof(struct allocExtDesc) + adsize;
-		} else {
-			loffset = epos->offset + adsize;
-			aed->lengthAllocDescs = cpu_to_le32(0);
-			sptr = ptr;
-			epos->offset = sizeof(struct allocExtDesc);
-
-			if (epos->bh) {
-				aed = (struct allocExtDesc *)epos->bh->b_data;
-				le32_add_cpu(&aed->lengthAllocDescs, adsize);
-			} else {
-				iinfo->i_lenAlloc += adsize;
-				mark_inode_dirty(inode);
-			}
-		}
-		if (UDF_SB(inode->i_sb)->s_udfrev >= 0x0200)
-			udf_new_tag(nbh->b_data, TAG_IDENT_AED, 3, 1,
-				    epos->block.logicalBlockNum, sizeof(struct tag));
-		else
-			udf_new_tag(nbh->b_data, TAG_IDENT_AED, 2, 1,
-				    epos->block.logicalBlockNum, sizeof(struct tag));
-		switch (iinfo->i_alloc_type) {
-		case ICBTAG_FLAG_AD_SHORT:
-			sad = (struct short_ad *)sptr;
-			sad->extLength = cpu_to_le32(EXT_NEXT_EXTENT_ALLOCDECS |
-						     inode->i_sb->s_blocksize);
-			sad->extPosition =
-				cpu_to_le32(epos->block.logicalBlockNum);
-			break;
-		case ICBTAG_FLAG_AD_LONG:
-			lad = (struct long_ad *)sptr;
-			lad->extLength = cpu_to_le32(EXT_NEXT_EXTENT_ALLOCDECS |
-						     inode->i_sb->s_blocksize);
-			lad->extLocation = cpu_to_lelb(epos->block);
-			memset(lad->impUse, 0x00, sizeof(lad->impUse));
-			break;
-		}
-		if (epos->bh) {
-			if (!UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_STRICT) ||
-			    UDF_SB(inode->i_sb)->s_udfrev >= 0x0201)
-				udf_update_tag(epos->bh->b_data, loffset);
-			else
-				udf_update_tag(epos->bh->b_data,
-						sizeof(struct allocExtDesc));
-			mark_buffer_dirty_inode(epos->bh, inode);
-			brelse(epos->bh);
-		} else {
-			mark_inode_dirty(inode);
-		}
-		epos->bh = nbh;
+	if (!epos->bh) {
+		WARN_ON(iinfo->i_lenAlloc !=
+			epos->offset - udf_file_entry_alloc_offset(inode));
+	} else {
+		aed = (struct allocExtDesc *)epos->bh->b_data;
+		WARN_ON(le32_to_cpu(aed->lengthAllocDescs) !=
+			epos->offset - sizeof(struct allocExtDesc));
+		WARN_ON(epos->offset + adsize > inode->i_sb->s_blocksize);
 	}
 
 	udf_write_aext(inode, epos, eloc, elen, inc);
@@ -1995,6 +1985,41 @@ int udf_add_aext(struct inode *inode, struct extent_position *epos,
 	return 0;
 }
 
+/*
+ * Append extent at given position - should be the first free one in inode
+ * / indirect extent. Takes care of allocating and linking indirect blocks.
+ */
+int udf_add_aext(struct inode *inode, struct extent_position *epos,
+		 struct kernel_lb_addr *eloc, uint32_t elen, int inc)
+{
+	int adsize;
+	struct super_block *sb = inode->i_sb;
+
+	if (UDF_I(inode)->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
+		adsize = sizeof(struct short_ad);
+	else if (UDF_I(inode)->i_alloc_type == ICBTAG_FLAG_AD_LONG)
+		adsize = sizeof(struct long_ad);
+	else
+		return -EIO;
+
+	if (epos->offset + (2 * adsize) > sb->s_blocksize) {
+		int err;
+		int new_block;
+
+		new_block = udf_new_block(sb, NULL,
+					  epos->block.partitionReferenceNum,
+					  epos->block.logicalBlockNum, &err);
+		if (!new_block)
+			return -ENOSPC;
+
+		err = udf_setup_indirect_aext(inode, new_block, epos);
+		if (err)
+			return err;
+	}
+
+	return __udf_add_aext(inode, epos, eloc, elen, inc);
+}
+
 void udf_write_aext(struct inode *inode, struct extent_position *epos,
 		    struct kernel_lb_addr *eloc, uint32_t elen, int inc)
 {

fs/udf/udfdecl.h

@@ -159,6 +159,10 @@ extern int udf_write_inode(struct inode *, struct writeback_control *wbc);
 extern long udf_block_map(struct inode *, sector_t);
 extern int8_t inode_bmap(struct inode *, sector_t, struct extent_position *,
 			 struct kernel_lb_addr *, uint32_t *, sector_t *);
+extern int udf_setup_indirect_aext(struct inode *inode, int block,
+				   struct extent_position *epos);
+extern int __udf_add_aext(struct inode *inode, struct extent_position *epos,
+			  struct kernel_lb_addr *eloc, uint32_t elen, int inc);
 extern int udf_add_aext(struct inode *, struct extent_position *,
 			struct kernel_lb_addr *, uint32_t, int);
 extern void udf_write_aext(struct inode *, struct extent_position *,