[PATCH v4 1/6] btrfs-progs: add raid-stripe-tree definitions

[Johannes Thumshirn <johannes.thumshirn@wdc.com>]

Add the definitions for the on-disk format of the RAID stripe tree.

Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
---
 kernel-shared/accessors.h       | 37 +++++++++++++++++++++++++++++++++++++
 kernel-shared/uapi/btrfs_tree.h | 26 ++++++++++++++++++++++++++
 2 files changed, 63 insertions(+)

diff --git a/kernel-shared/accessors.h b/kernel-shared/accessors.h
index 625acfbe8ca7..80635f31c90b 100644
--- a/kernel-shared/accessors.h
+++ b/kernel-shared/accessors.h
@@ -270,6 +270,43 @@ BTRFS_SETGET_FUNCS(free_space_extent_count, struct btrfs_free_space_info,
 		   extent_count, 32);
 BTRFS_SETGET_FUNCS(free_space_flags, struct btrfs_free_space_info, flags, 32);
 
+/* struct btrfs_stripe_extent */
+BTRFS_SETGET_FUNCS(stripe_extent_encoding, struct btrfs_stripe_extent, encoding, 8);
+BTRFS_SETGET_FUNCS(raid_stride_devid, struct btrfs_raid_stride, devid, 64);
+BTRFS_SETGET_FUNCS(raid_stride_offset, struct btrfs_raid_stride, offset, 64);
+BTRFS_SETGET_FUNCS(raid_stride_length, struct btrfs_raid_stride, length, 64);
+
+static inline struct btrfs_raid_stride *btrfs_raid_stride_nr(
+						 struct btrfs_stripe_extent *dps,
+						 int nr)
+{
+	unsigned long offset = (unsigned long)dps;
+	offset += offsetof(struct btrfs_stripe_extent, strides);
+	offset += nr * sizeof(struct btrfs_raid_stride);
+	return (struct btrfs_raid_stride *)offset;
+}
+
+static inline u64 btrfs_raid_stride_devid_nr(struct extent_buffer *eb,
+					       struct btrfs_stripe_extent *dps,
+					       int nr)
+{
+	return btrfs_raid_stride_devid(eb, btrfs_raid_stride_nr(dps, nr));
+}
+
+static inline u64 btrfs_raid_stride_offset_nr(struct extent_buffer *eb,
+						struct btrfs_stripe_extent *dps,
+						int nr)
+{
+	return btrfs_raid_stride_offset(eb, btrfs_raid_stride_nr(dps, nr));
+}
+
+static inline u64 btrfs_raid_stride_length_nr(struct extent_buffer *eb,
+						struct btrfs_stripe_extent *dps,
+						int nr)
+{
+	return btrfs_raid_stride_length(eb, btrfs_raid_stride_nr(dps, nr));
+}
+
 /* struct btrfs_inode_ref */
 BTRFS_SETGET_FUNCS(inode_ref_name_len, struct btrfs_inode_ref, name_len, 16);
 BTRFS_SETGET_FUNCS(inode_ref_index, struct btrfs_inode_ref, index, 64);
diff --git a/kernel-shared/uapi/btrfs_tree.h b/kernel-shared/uapi/btrfs_tree.h
index ad555e7055ab..73411a8697ce 100644
--- a/kernel-shared/uapi/btrfs_tree.h
+++ b/kernel-shared/uapi/btrfs_tree.h
@@ -699,6 +699,32 @@ struct btrfs_super_block {
 	__u8 padding[565];
 } __attribute__ ((__packed__));
 
+struct btrfs_raid_stride {
+	/* btrfs device-id this raid extent  lives on */
+	__le64 devid;
+	/* offset from  the devextent start */
+	__le64 offset;
+	/* length of the stride on disk */
+	__le64 length;
+} __attribute__ ((__packed__));
+
+/* The stripe_extent::encoding, 1:1 mapping of enum btrfs_raid_types */
+#define BTRFS_STRIPE_RAID0	1
+#define BTRFS_STRIPE_RAID1	2
+#define BTRFS_STRIPE_DUP	3
+#define BTRFS_STRIPE_RAID10	4
+#define BTRFS_STRIPE_RAID5	5
+#define BTRFS_STRIPE_RAID6	6
+#define BTRFS_STRIPE_RAID1C3	7
+#define BTRFS_STRIPE_RAID1C4	8
+
+struct btrfs_stripe_extent {
+	u8 encoding;
+	u8 reserved[7];
+	/* array of raid strides this stripe is comprised of */
+	struct btrfs_raid_stride strides;
+} __attribute__ ((__packed__));
+
 #define BTRFS_FREE_SPACE_EXTENT	1
 #define BTRFS_FREE_SPACE_BITMAP	2
 

-- 
2.41.0