1 files changed, 192 insertions, 0 deletions
diff --git a/fs/btrfs/ordered-data.h b/fs/btrfs/ordered-data.h
new file mode 100644
index 000000000..02d813aaa
--- /dev/null
+++ b/fs/btrfs/ordered-data.h
@@ -0,0 +1,192 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2007 Oracle.  All rights reserved.
+ */
+
+#ifndef BTRFS_ORDERED_DATA_H
+#define BTRFS_ORDERED_DATA_H
+
+/* one of these per inode */
+struct btrfs_ordered_inode_tree {
+	spinlock_t lock;
+	struct rb_root tree;
+	struct rb_node *last;
+};
+
+struct btrfs_ordered_sum {
+	/* bytenr is the start of this extent on disk */
+	u64 bytenr;
+
+	/*
+	 * this is the length in bytes covered by the sums array below.
+	 */
+	int len;
+	struct list_head list;
+	/* last field is a variable length array of csums */
+	u32 sums[];
+};
+
+/*
+ * bits for the flags field:
+ *
+ * BTRFS_ORDERED_IO_DONE is set when all of the blocks are written.
+ * It is used to make sure metadata is inserted into the tree only once
+ * per extent.
+ *
+ * BTRFS_ORDERED_COMPLETE is set when the extent is removed from the
+ * rbtree, just before waking any waiters.  It is used to indicate the
+ * IO is done and any metadata is inserted into the tree.
+ */
+#define BTRFS_ORDERED_IO_DONE 0 /* set when all the pages are written */
+
+#define BTRFS_ORDERED_COMPLETE 1 /* set when removed from the tree */
+
+#define BTRFS_ORDERED_NOCOW 2 /* set when we want to write in place */
+
+#define BTRFS_ORDERED_COMPRESSED 3 /* writing a zlib compressed extent */
+
+#define BTRFS_ORDERED_PREALLOC 4 /* set when writing to preallocated extent */
+
+#define BTRFS_ORDERED_DIRECT 5 /* set when we're doing DIO with this extent */
+
+#define BTRFS_ORDERED_IOERR 6 /* We had an io error when writing this out */
+
+#define BTRFS_ORDERED_UPDATED_ISIZE 7 /* indicates whether this ordered extent
+				       * has done its due diligence in updating
+				       * the isize. */
+#define BTRFS_ORDERED_TRUNCATED 8 /* Set when we have to truncate an extent */
+
+#define BTRFS_ORDERED_PENDING 9 /* We are waiting for this ordered extent to
+				  * complete in the current transaction. */
+#define BTRFS_ORDERED_REGULAR 10 /* Regular IO for COW */
+
+struct btrfs_ordered_extent {
+	/* logical offset in the file */
+	u64 file_offset;
+
+	/* disk byte number */
+	u64 start;
+
+	/* ram length of the extent in bytes */
+	u64 len;
+
+	/* extent length on disk */
+	u64 disk_len;
+
+	/* number of bytes that still need writing */
+	u64 bytes_left;
+
+	/*
+	 * the end of the ordered extent which is behind it but
+	 * didn't update disk_i_size. Please see the comment of
+	 * btrfs_ordered_update_i_size();
+	 */
+	u64 outstanding_isize;
+
+	/*
+	 * If we get truncated we need to adjust the file extent we enter for
+	 * this ordered extent so that we do not expose stale data.
+	 */
+	u64 truncated_len;
+
+	/* flags (described above) */
+	unsigned long flags;
+
+	/* compression algorithm */
+	int compress_type;
+
+	/* reference count */
+	refcount_t refs;
+
+	/* the inode we belong to */
+	struct inode *inode;
+
+	/* list of checksums for insertion when the extent io is done */
+	struct list_head list;
+
+	/* If we need to wait on this to be done */
+	struct list_head log_list;
+
+	/* If the transaction needs to wait on this ordered extent */
+	struct list_head trans_list;
+
+	/* used to wait for the BTRFS_ORDERED_COMPLETE bit */
+	wait_queue_head_t wait;
+
+	/* our friendly rbtree entry */
+	struct rb_node rb_node;
+
+	/* a per root list of all the pending ordered extents */
+	struct list_head root_extent_list;
+
+	struct btrfs_work work;
+
+	struct completion completion;
+	struct btrfs_work flush_work;
+	struct list_head work_list;
+};
+
+/*
+ * calculates the total size you need to allocate for an ordered sum
+ * structure spanning 'bytes' in the file
+ */
+static inline int btrfs_ordered_sum_size(struct btrfs_fs_info *fs_info,
+					 unsigned long bytes)
+{
+	int num_sectors = (int)DIV_ROUND_UP(bytes, fs_info->sectorsize);
+	int csum_size = btrfs_super_csum_size(fs_info->super_copy);
+
+	return sizeof(struct btrfs_ordered_sum) + num_sectors * csum_size;
+}
+
+static inline void
+btrfs_ordered_inode_tree_init(struct btrfs_ordered_inode_tree *t)
+{
+	spin_lock_init(&t->lock);
+	t->tree = RB_ROOT;
+	t->last = NULL;
+}
+
+void btrfs_put_ordered_extent(struct btrfs_ordered_extent *entry);
+void btrfs_remove_ordered_extent(struct inode *inode,
+				struct btrfs_ordered_extent *entry);
+int btrfs_dec_test_ordered_pending(struct inode *inode,
+				   struct btrfs_ordered_extent **cached,
+				   u64 file_offset, u64 io_size, int uptodate);
+int btrfs_dec_test_first_ordered_pending(struct inode *inode,
+				   struct btrfs_ordered_extent **cached,
+				   u64 *file_offset, u64 io_size,
+				   int uptodate);
+int btrfs_add_ordered_extent(struct inode *inode, u64 file_offset,
+			     u64 start, u64 len, u64 disk_len, int type);
+int btrfs_add_ordered_extent_dio(struct inode *inode, u64 file_offset,
+				 u64 start, u64 len, u64 disk_len, int type);
+int btrfs_add_ordered_extent_compress(struct inode *inode, u64 file_offset,
+				      u64 start, u64 len, u64 disk_len,
+				      int type, int compress_type);
+void btrfs_add_ordered_sum(struct inode *inode,
+			   struct btrfs_ordered_extent *entry,
+			   struct btrfs_ordered_sum *sum);
+struct btrfs_ordered_extent *btrfs_lookup_ordered_extent(struct inode *inode,
+							 u64 file_offset);
+void btrfs_start_ordered_extent(struct inode *inode,
+				struct btrfs_ordered_extent *entry, int wait);
+int btrfs_wait_ordered_range(struct inode *inode, u64 start, u64 len);
+struct btrfs_ordered_extent *
+btrfs_lookup_first_ordered_extent(struct inode * inode, u64 file_offset);
+struct btrfs_ordered_extent *btrfs_lookup_ordered_range(
+		struct btrfs_inode *inode,
+		u64 file_offset,
+		u64 len);
+int btrfs_ordered_update_i_size(struct inode *inode, u64 offset,
+				struct btrfs_ordered_extent *ordered);
+int btrfs_find_ordered_sum(struct inode *inode, u64 offset, u64 disk_bytenr,
+			   u32 *sum, int len);
+u64 btrfs_wait_ordered_extents(struct btrfs_root *root, u64 nr,
+			       const u64 range_start, const u64 range_len);
+u64 btrfs_wait_ordered_roots(struct btrfs_fs_info *fs_info, u64 nr,
+			      const u64 range_start, const u64 range_len);
+int __init ordered_data_init(void);
+void __cold ordered_data_exit(void);
+
+#endif