v4.19.13 snapshot.
diff --git a/fs/xfs/libxfs/xfs_btree.h b/fs/xfs/libxfs/xfs_btree.h
new file mode 100644
index 0000000..e3b3e9d
--- /dev/null
+++ b/fs/xfs/libxfs/xfs_btree.h
@@ -0,0 +1,517 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2000-2001,2005 Silicon Graphics, Inc.
+ * All Rights Reserved.
+ */
+#ifndef __XFS_BTREE_H__
+#define	__XFS_BTREE_H__
+
+struct xfs_buf;
+struct xfs_inode;
+struct xfs_mount;
+struct xfs_trans;
+
+extern kmem_zone_t	*xfs_btree_cur_zone;
+
+/*
+ * Generic key, ptr and record wrapper structures.
+ *
+ * These are disk format structures, and are converted where necessary
+ * by the btree specific code that needs to interpret them.
+ */
+union xfs_btree_ptr {
+	__be32			s;	/* short form ptr */
+	__be64			l;	/* long form ptr */
+};
+
+/*
+ * The in-core btree key.  Overlapping btrees actually store two keys
+ * per pointer, so we reserve enough memory to hold both.  The __*bigkey
+ * items should never be accessed directly.
+ */
+union xfs_btree_key {
+	struct xfs_bmbt_key		bmbt;
+	xfs_bmdr_key_t			bmbr;	/* bmbt root block */
+	xfs_alloc_key_t			alloc;
+	struct xfs_inobt_key		inobt;
+	struct xfs_rmap_key		rmap;
+	struct xfs_rmap_key		__rmap_bigkey[2];
+	struct xfs_refcount_key		refc;
+};
+
+union xfs_btree_rec {
+	struct xfs_bmbt_rec		bmbt;
+	xfs_bmdr_rec_t			bmbr;	/* bmbt root block */
+	struct xfs_alloc_rec		alloc;
+	struct xfs_inobt_rec		inobt;
+	struct xfs_rmap_rec		rmap;
+	struct xfs_refcount_rec		refc;
+};
+
+/*
+ * This nonsense is to make -wlint happy.
+ */
+#define	XFS_LOOKUP_EQ	((xfs_lookup_t)XFS_LOOKUP_EQi)
+#define	XFS_LOOKUP_LE	((xfs_lookup_t)XFS_LOOKUP_LEi)
+#define	XFS_LOOKUP_GE	((xfs_lookup_t)XFS_LOOKUP_GEi)
+
+#define	XFS_BTNUM_BNO	((xfs_btnum_t)XFS_BTNUM_BNOi)
+#define	XFS_BTNUM_CNT	((xfs_btnum_t)XFS_BTNUM_CNTi)
+#define	XFS_BTNUM_BMAP	((xfs_btnum_t)XFS_BTNUM_BMAPi)
+#define	XFS_BTNUM_INO	((xfs_btnum_t)XFS_BTNUM_INOi)
+#define	XFS_BTNUM_FINO	((xfs_btnum_t)XFS_BTNUM_FINOi)
+#define	XFS_BTNUM_RMAP	((xfs_btnum_t)XFS_BTNUM_RMAPi)
+#define	XFS_BTNUM_REFC	((xfs_btnum_t)XFS_BTNUM_REFCi)
+
+uint32_t xfs_btree_magic(int crc, xfs_btnum_t btnum);
+
+/*
+ * For logging record fields.
+ */
+#define	XFS_BB_MAGIC		(1 << 0)
+#define	XFS_BB_LEVEL		(1 << 1)
+#define	XFS_BB_NUMRECS		(1 << 2)
+#define	XFS_BB_LEFTSIB		(1 << 3)
+#define	XFS_BB_RIGHTSIB		(1 << 4)
+#define	XFS_BB_BLKNO		(1 << 5)
+#define	XFS_BB_LSN		(1 << 6)
+#define	XFS_BB_UUID		(1 << 7)
+#define	XFS_BB_OWNER		(1 << 8)
+#define	XFS_BB_NUM_BITS		5
+#define	XFS_BB_ALL_BITS		((1 << XFS_BB_NUM_BITS) - 1)
+#define	XFS_BB_NUM_BITS_CRC	9
+#define	XFS_BB_ALL_BITS_CRC	((1 << XFS_BB_NUM_BITS_CRC) - 1)
+
+/*
+ * Generic stats interface
+ */
+#define XFS_BTREE_STATS_INC(cur, stat)	\
+	XFS_STATS_INC_OFF((cur)->bc_mp, (cur)->bc_statoff + __XBTS_ ## stat)
+#define XFS_BTREE_STATS_ADD(cur, stat, val)	\
+	XFS_STATS_ADD_OFF((cur)->bc_mp, (cur)->bc_statoff + __XBTS_ ## stat, val)
+
+#define	XFS_BTREE_MAXLEVELS	9	/* max of all btrees */
+
+struct xfs_btree_ops {
+	/* size of the key and record structures */
+	size_t	key_len;
+	size_t	rec_len;
+
+	/* cursor operations */
+	struct xfs_btree_cur *(*dup_cursor)(struct xfs_btree_cur *);
+	void	(*update_cursor)(struct xfs_btree_cur *src,
+				 struct xfs_btree_cur *dst);
+
+	/* update btree root pointer */
+	void	(*set_root)(struct xfs_btree_cur *cur,
+			    union xfs_btree_ptr *nptr, int level_change);
+
+	/* block allocation / freeing */
+	int	(*alloc_block)(struct xfs_btree_cur *cur,
+			       union xfs_btree_ptr *start_bno,
+			       union xfs_btree_ptr *new_bno,
+			       int *stat);
+	int	(*free_block)(struct xfs_btree_cur *cur, struct xfs_buf *bp);
+
+	/* update last record information */
+	void	(*update_lastrec)(struct xfs_btree_cur *cur,
+				  struct xfs_btree_block *block,
+				  union xfs_btree_rec *rec,
+				  int ptr, int reason);
+
+	/* records in block/level */
+	int	(*get_minrecs)(struct xfs_btree_cur *cur, int level);
+	int	(*get_maxrecs)(struct xfs_btree_cur *cur, int level);
+
+	/* records on disk.  Matter for the root in inode case. */
+	int	(*get_dmaxrecs)(struct xfs_btree_cur *cur, int level);
+
+	/* init values of btree structures */
+	void	(*init_key_from_rec)(union xfs_btree_key *key,
+				     union xfs_btree_rec *rec);
+	void	(*init_rec_from_cur)(struct xfs_btree_cur *cur,
+				     union xfs_btree_rec *rec);
+	void	(*init_ptr_from_cur)(struct xfs_btree_cur *cur,
+				     union xfs_btree_ptr *ptr);
+	void	(*init_high_key_from_rec)(union xfs_btree_key *key,
+					  union xfs_btree_rec *rec);
+
+	/* difference between key value and cursor value */
+	int64_t (*key_diff)(struct xfs_btree_cur *cur,
+			      union xfs_btree_key *key);
+
+	/*
+	 * Difference between key2 and key1 -- positive if key1 > key2,
+	 * negative if key1 < key2, and zero if equal.
+	 */
+	int64_t (*diff_two_keys)(struct xfs_btree_cur *cur,
+				   union xfs_btree_key *key1,
+				   union xfs_btree_key *key2);
+
+	const struct xfs_buf_ops	*buf_ops;
+
+	/* check that k1 is lower than k2 */
+	int	(*keys_inorder)(struct xfs_btree_cur *cur,
+				union xfs_btree_key *k1,
+				union xfs_btree_key *k2);
+
+	/* check that r1 is lower than r2 */
+	int	(*recs_inorder)(struct xfs_btree_cur *cur,
+				union xfs_btree_rec *r1,
+				union xfs_btree_rec *r2);
+};
+
+/*
+ * Reasons for the update_lastrec method to be called.
+ */
+#define LASTREC_UPDATE	0
+#define LASTREC_INSREC	1
+#define LASTREC_DELREC	2
+
+
+union xfs_btree_irec {
+	struct xfs_alloc_rec_incore	a;
+	struct xfs_bmbt_irec		b;
+	struct xfs_inobt_rec_incore	i;
+	struct xfs_rmap_irec		r;
+	struct xfs_refcount_irec	rc;
+};
+
+/* Per-AG btree private information. */
+union xfs_btree_cur_private {
+	struct {
+		unsigned long	nr_ops;		/* # record updates */
+		int		shape_changes;	/* # of extent splits */
+	} refc;
+};
+
+/*
+ * Btree cursor structure.
+ * This collects all information needed by the btree code in one place.
+ */
+typedef struct xfs_btree_cur
+{
+	struct xfs_trans	*bc_tp;	/* transaction we're in, if any */
+	struct xfs_mount	*bc_mp;	/* file system mount struct */
+	const struct xfs_btree_ops *bc_ops;
+	uint			bc_flags; /* btree features - below */
+	union xfs_btree_irec	bc_rec;	/* current insert/search record value */
+	struct xfs_buf	*bc_bufs[XFS_BTREE_MAXLEVELS];	/* buf ptr per level */
+	int		bc_ptrs[XFS_BTREE_MAXLEVELS];	/* key/record # */
+	uint8_t		bc_ra[XFS_BTREE_MAXLEVELS];	/* readahead bits */
+#define	XFS_BTCUR_LEFTRA	1	/* left sibling has been read-ahead */
+#define	XFS_BTCUR_RIGHTRA	2	/* right sibling has been read-ahead */
+	uint8_t		bc_nlevels;	/* number of levels in the tree */
+	uint8_t		bc_blocklog;	/* log2(blocksize) of btree blocks */
+	xfs_btnum_t	bc_btnum;	/* identifies which btree type */
+	int		bc_statoff;	/* offset of btre stats array */
+	union {
+		struct {			/* needed for BNO, CNT, INO */
+			struct xfs_buf	*agbp;	/* agf/agi buffer pointer */
+			xfs_agnumber_t	agno;	/* ag number */
+			union xfs_btree_cur_private	priv;
+		} a;
+		struct {			/* needed for BMAP */
+			struct xfs_inode *ip;	/* pointer to our inode */
+			int		allocated;	/* count of alloced */
+			short		forksize;	/* fork's inode space */
+			char		whichfork;	/* data or attr fork */
+			char		flags;		/* flags */
+#define	XFS_BTCUR_BPRV_WASDEL		(1<<0)		/* was delayed */
+#define	XFS_BTCUR_BPRV_INVALID_OWNER	(1<<1)		/* for ext swap */
+		} b;
+	}		bc_private;	/* per-btree type data */
+} xfs_btree_cur_t;
+
+/* cursor flags */
+#define XFS_BTREE_LONG_PTRS		(1<<0)	/* pointers are 64bits long */
+#define XFS_BTREE_ROOT_IN_INODE		(1<<1)	/* root may be variable size */
+#define XFS_BTREE_LASTREC_UPDATE	(1<<2)	/* track last rec externally */
+#define XFS_BTREE_CRC_BLOCKS		(1<<3)	/* uses extended btree blocks */
+#define XFS_BTREE_OVERLAPPING		(1<<4)	/* overlapping intervals */
+
+
+#define	XFS_BTREE_NOERROR	0
+#define	XFS_BTREE_ERROR		1
+
+/*
+ * Convert from buffer to btree block header.
+ */
+#define	XFS_BUF_TO_BLOCK(bp)	((struct xfs_btree_block *)((bp)->b_addr))
+
+/*
+ * Internal long and short btree block checks.  They return NULL if the
+ * block is ok or the address of the failed check otherwise.
+ */
+xfs_failaddr_t __xfs_btree_check_lblock(struct xfs_btree_cur *cur,
+		struct xfs_btree_block *block, int level, struct xfs_buf *bp);
+xfs_failaddr_t __xfs_btree_check_sblock(struct xfs_btree_cur *cur,
+		struct xfs_btree_block *block, int level, struct xfs_buf *bp);
+
+/*
+ * Check that block header is ok.
+ */
+int
+xfs_btree_check_block(
+	struct xfs_btree_cur	*cur,	/* btree cursor */
+	struct xfs_btree_block	*block,	/* generic btree block pointer */
+	int			level,	/* level of the btree block */
+	struct xfs_buf		*bp);	/* buffer containing block, if any */
+
+/*
+ * Check that (long) pointer is ok.
+ */
+bool					/* error (0 or EFSCORRUPTED) */
+xfs_btree_check_lptr(
+	struct xfs_btree_cur	*cur,	/* btree cursor */
+	xfs_fsblock_t		fsbno,	/* btree block disk address */
+	int			level);	/* btree block level */
+
+/*
+ * Check that (short) pointer is ok.
+ */
+bool					/* error (0 or EFSCORRUPTED) */
+xfs_btree_check_sptr(
+	struct xfs_btree_cur	*cur,	/* btree cursor */
+	xfs_agblock_t		agbno,	/* btree block disk address */
+	int			level);	/* btree block level */
+
+/*
+ * Delete the btree cursor.
+ */
+void
+xfs_btree_del_cursor(
+	xfs_btree_cur_t		*cur,	/* btree cursor */
+	int			error);	/* del because of error */
+
+/*
+ * Duplicate the btree cursor.
+ * Allocate a new one, copy the record, re-get the buffers.
+ */
+int					/* error */
+xfs_btree_dup_cursor(
+	xfs_btree_cur_t		*cur,	/* input cursor */
+	xfs_btree_cur_t		**ncur);/* output cursor */
+
+/*
+ * Get a buffer for the block, return it with no data read.
+ * Long-form addressing.
+ */
+struct xfs_buf *				/* buffer for fsbno */
+xfs_btree_get_bufl(
+	struct xfs_mount	*mp,	/* file system mount point */
+	struct xfs_trans	*tp,	/* transaction pointer */
+	xfs_fsblock_t		fsbno,	/* file system block number */
+	uint			lock);	/* lock flags for get_buf */
+
+/*
+ * Get a buffer for the block, return it with no data read.
+ * Short-form addressing.
+ */
+struct xfs_buf *				/* buffer for agno/agbno */
+xfs_btree_get_bufs(
+	struct xfs_mount	*mp,	/* file system mount point */
+	struct xfs_trans	*tp,	/* transaction pointer */
+	xfs_agnumber_t		agno,	/* allocation group number */
+	xfs_agblock_t		agbno,	/* allocation group block number */
+	uint			lock);	/* lock flags for get_buf */
+
+/*
+ * Check for the cursor referring to the last block at the given level.
+ */
+int					/* 1=is last block, 0=not last block */
+xfs_btree_islastblock(
+	xfs_btree_cur_t		*cur,	/* btree cursor */
+	int			level);	/* level to check */
+
+/*
+ * Compute first and last byte offsets for the fields given.
+ * Interprets the offsets table, which contains struct field offsets.
+ */
+void
+xfs_btree_offsets(
+	int64_t			fields,	/* bitmask of fields */
+	const short		*offsets,/* table of field offsets */
+	int			nbits,	/* number of bits to inspect */
+	int			*first,	/* output: first byte offset */
+	int			*last);	/* output: last byte offset */
+
+/*
+ * Get a buffer for the block, return it read in.
+ * Long-form addressing.
+ */
+int					/* error */
+xfs_btree_read_bufl(
+	struct xfs_mount	*mp,	/* file system mount point */
+	struct xfs_trans	*tp,	/* transaction pointer */
+	xfs_fsblock_t		fsbno,	/* file system block number */
+	uint			lock,	/* lock flags for read_buf */
+	struct xfs_buf		**bpp,	/* buffer for fsbno */
+	int			refval,	/* ref count value for buffer */
+	const struct xfs_buf_ops *ops);
+
+/*
+ * Read-ahead the block, don't wait for it, don't return a buffer.
+ * Long-form addressing.
+ */
+void					/* error */
+xfs_btree_reada_bufl(
+	struct xfs_mount	*mp,	/* file system mount point */
+	xfs_fsblock_t		fsbno,	/* file system block number */
+	xfs_extlen_t		count,	/* count of filesystem blocks */
+	const struct xfs_buf_ops *ops);
+
+/*
+ * Read-ahead the block, don't wait for it, don't return a buffer.
+ * Short-form addressing.
+ */
+void					/* error */
+xfs_btree_reada_bufs(
+	struct xfs_mount	*mp,	/* file system mount point */
+	xfs_agnumber_t		agno,	/* allocation group number */
+	xfs_agblock_t		agbno,	/* allocation group block number */
+	xfs_extlen_t		count,	/* count of filesystem blocks */
+	const struct xfs_buf_ops *ops);
+
+/*
+ * Initialise a new btree block header
+ */
+void
+xfs_btree_init_block(
+	struct xfs_mount *mp,
+	struct xfs_buf	*bp,
+	xfs_btnum_t	btnum,
+	__u16		level,
+	__u16		numrecs,
+	__u64		owner,
+	unsigned int	flags);
+
+void
+xfs_btree_init_block_int(
+	struct xfs_mount	*mp,
+	struct xfs_btree_block	*buf,
+	xfs_daddr_t		blkno,
+	xfs_btnum_t		btnum,
+	__u16			level,
+	__u16			numrecs,
+	__u64			owner,
+	unsigned int		flags);
+
+/*
+ * Common btree core entry points.
+ */
+int xfs_btree_increment(struct xfs_btree_cur *, int, int *);
+int xfs_btree_decrement(struct xfs_btree_cur *, int, int *);
+int xfs_btree_lookup(struct xfs_btree_cur *, xfs_lookup_t, int *);
+int xfs_btree_update(struct xfs_btree_cur *, union xfs_btree_rec *);
+int xfs_btree_new_iroot(struct xfs_btree_cur *, int *, int *);
+int xfs_btree_insert(struct xfs_btree_cur *, int *);
+int xfs_btree_delete(struct xfs_btree_cur *, int *);
+int xfs_btree_get_rec(struct xfs_btree_cur *, union xfs_btree_rec **, int *);
+int xfs_btree_change_owner(struct xfs_btree_cur *cur, uint64_t new_owner,
+			   struct list_head *buffer_list);
+
+/*
+ * btree block CRC helpers
+ */
+void xfs_btree_lblock_calc_crc(struct xfs_buf *);
+bool xfs_btree_lblock_verify_crc(struct xfs_buf *);
+void xfs_btree_sblock_calc_crc(struct xfs_buf *);
+bool xfs_btree_sblock_verify_crc(struct xfs_buf *);
+
+/*
+ * Internal btree helpers also used by xfs_bmap.c.
+ */
+void xfs_btree_log_block(struct xfs_btree_cur *, struct xfs_buf *, int);
+void xfs_btree_log_recs(struct xfs_btree_cur *, struct xfs_buf *, int, int);
+
+/*
+ * Helpers.
+ */
+static inline int xfs_btree_get_numrecs(struct xfs_btree_block *block)
+{
+	return be16_to_cpu(block->bb_numrecs);
+}
+
+static inline void xfs_btree_set_numrecs(struct xfs_btree_block *block,
+		uint16_t numrecs)
+{
+	block->bb_numrecs = cpu_to_be16(numrecs);
+}
+
+static inline int xfs_btree_get_level(struct xfs_btree_block *block)
+{
+	return be16_to_cpu(block->bb_level);
+}
+
+
+/*
+ * Min and max functions for extlen, agblock, fileoff, and filblks types.
+ */
+#define	XFS_EXTLEN_MIN(a,b)	min_t(xfs_extlen_t, (a), (b))
+#define	XFS_EXTLEN_MAX(a,b)	max_t(xfs_extlen_t, (a), (b))
+#define	XFS_AGBLOCK_MIN(a,b)	min_t(xfs_agblock_t, (a), (b))
+#define	XFS_AGBLOCK_MAX(a,b)	max_t(xfs_agblock_t, (a), (b))
+#define	XFS_FILEOFF_MIN(a,b)	min_t(xfs_fileoff_t, (a), (b))
+#define	XFS_FILEOFF_MAX(a,b)	max_t(xfs_fileoff_t, (a), (b))
+#define	XFS_FILBLKS_MIN(a,b)	min_t(xfs_filblks_t, (a), (b))
+#define	XFS_FILBLKS_MAX(a,b)	max_t(xfs_filblks_t, (a), (b))
+
+xfs_failaddr_t xfs_btree_sblock_v5hdr_verify(struct xfs_buf *bp);
+xfs_failaddr_t xfs_btree_sblock_verify(struct xfs_buf *bp,
+		unsigned int max_recs);
+xfs_failaddr_t xfs_btree_lblock_v5hdr_verify(struct xfs_buf *bp,
+		uint64_t owner);
+xfs_failaddr_t xfs_btree_lblock_verify(struct xfs_buf *bp,
+		unsigned int max_recs);
+
+uint xfs_btree_compute_maxlevels(uint *limits, unsigned long len);
+unsigned long long xfs_btree_calc_size(uint *limits, unsigned long long len);
+
+/* return codes */
+#define XFS_BTREE_QUERY_RANGE_CONTINUE	0	/* keep iterating */
+#define XFS_BTREE_QUERY_RANGE_ABORT	1	/* stop iterating */
+typedef int (*xfs_btree_query_range_fn)(struct xfs_btree_cur *cur,
+		union xfs_btree_rec *rec, void *priv);
+
+int xfs_btree_query_range(struct xfs_btree_cur *cur,
+		union xfs_btree_irec *low_rec, union xfs_btree_irec *high_rec,
+		xfs_btree_query_range_fn fn, void *priv);
+int xfs_btree_query_all(struct xfs_btree_cur *cur, xfs_btree_query_range_fn fn,
+		void *priv);
+
+typedef int (*xfs_btree_visit_blocks_fn)(struct xfs_btree_cur *cur, int level,
+		void *data);
+int xfs_btree_visit_blocks(struct xfs_btree_cur *cur,
+		xfs_btree_visit_blocks_fn fn, void *data);
+
+int xfs_btree_count_blocks(struct xfs_btree_cur *cur, xfs_extlen_t *blocks);
+
+union xfs_btree_rec *xfs_btree_rec_addr(struct xfs_btree_cur *cur, int n,
+		struct xfs_btree_block *block);
+union xfs_btree_key *xfs_btree_key_addr(struct xfs_btree_cur *cur, int n,
+		struct xfs_btree_block *block);
+union xfs_btree_key *xfs_btree_high_key_addr(struct xfs_btree_cur *cur, int n,
+		struct xfs_btree_block *block);
+union xfs_btree_ptr *xfs_btree_ptr_addr(struct xfs_btree_cur *cur, int n,
+		struct xfs_btree_block *block);
+int xfs_btree_lookup_get_block(struct xfs_btree_cur *cur, int level,
+		union xfs_btree_ptr *pp, struct xfs_btree_block **blkp);
+struct xfs_btree_block *xfs_btree_get_block(struct xfs_btree_cur *cur,
+		int level, struct xfs_buf **bpp);
+bool xfs_btree_ptr_is_null(struct xfs_btree_cur *cur, union xfs_btree_ptr *ptr);
+int64_t xfs_btree_diff_two_ptrs(struct xfs_btree_cur *cur,
+				const union xfs_btree_ptr *a,
+				const union xfs_btree_ptr *b);
+void xfs_btree_get_sibling(struct xfs_btree_cur *cur,
+			   struct xfs_btree_block *block,
+			   union xfs_btree_ptr *ptr, int lr);
+void xfs_btree_get_keys(struct xfs_btree_cur *cur,
+		struct xfs_btree_block *block, union xfs_btree_key *key);
+union xfs_btree_key *xfs_btree_high_key_from_key(struct xfs_btree_cur *cur,
+		union xfs_btree_key *key);
+int xfs_btree_has_record(struct xfs_btree_cur *cur, union xfs_btree_irec *low,
+		union xfs_btree_irec *high, bool *exists);
+bool xfs_btree_has_more_records(struct xfs_btree_cur *cur);
+
+#endif	/* __XFS_BTREE_H__ */