/* SPDX-License-Identifier: GPL-2.0-or-later */
/*
 *   Copyright (C) International Business Machines Corp., 2000-2002
 */
#ifndef _H_JFS_XTREE
#define _H_JFS_XTREE

/*
 *      jfs_xtree.h: extent allocation descriptor B+-tree manager
 */

#include "jfs_btree.h"


/*
 *      extent allocation descriptor (xad)
 */
typedef struct xad {
        __u8 flag;      /* 1: flag */
        __u8 rsvrd[2];  /* 2: reserved */
        __u8 off1;      /* 1: offset in unit of fsblksize */
        __le32 off2;    /* 4: offset in unit of fsblksize */
        pxd_t loc;      /* 8: length and address in unit of fsblksize */
} xad_t;                        /* (16) */

#define MAXXLEN         ((1 << 24) - 1)

#define XTSLOTSIZE      16
#define L2XTSLOTSIZE    4

/* xad_t field construction */
#define XADoffset(xad, offset64)\
{\
        (xad)->off1 = ((u64)offset64) >> 32;\
        (xad)->off2 = __cpu_to_le32((offset64) & 0xffffffff);\
}
#define XADaddress(xad, address64) PXDaddress(&(xad)->loc, address64)
#define XADlength(xad, length32) PXDlength(&(xad)->loc, length32)

/* xad_t field extraction */
#define offsetXAD(xad)\
        ( ((s64)((xad)->off1)) << 32 | __le32_to_cpu((xad)->off2))
#define addressXAD(xad) addressPXD(&(xad)->loc)
#define lengthXAD(xad) lengthPXD(&(xad)->loc)

/* xad list */
struct xadlist {
        s16 maxnxad;
        s16 nxad;
        xad_t *xad;
};

/* xad_t flags */
#define XAD_NEW         0x01    /* new */
#define XAD_EXTENDED    0x02    /* extended */
#define XAD_COMPRESSED  0x04    /* compressed with recorded length */
#define XAD_NOTRECORDED 0x08    /* allocated but not recorded */
#define XAD_COW         0x10    /* copy-on-write */


/* possible values for maxentry */
#define XTROOTINITSLOT_DIR 6
#define XTROOTINITSLOT  10
#define XTROOTMAXSLOT   18
#define XTPAGEMAXSLOT   256
#define XTENTRYSTART    2

struct xtheader {
        __le64 next;    /* 8: */
        __le64 prev;    /* 8: */

        u8 flag;        /* 1: */
        u8 rsrvd1;      /* 1: */
        __le16 nextindex;       /* 2: next index = number of entries */
        __le16 maxentry;        /* 2: max number of entries */
        __le16 rsrvd2;  /* 2: */

        pxd_t self;     /* 8: self */
};

/*
 *      xtree root (in inode):
 */
typedef union {
        struct xtheader header;
        xad_t xad[XTROOTMAXSLOT];       /* 16 * maxentry: xad array */
} xtroot_t;

/*
 *      xtree page:
 */
typedef union {
        struct xtheader header;
        xad_t xad[XTPAGEMAXSLOT];       /* 16 * maxentry: xad array */
} xtpage_t;

/*
 *      external declaration
 */
extern int xtLookup(struct inode *ip, s64 lstart, s64 llen,
                    int *pflag, s64 * paddr, int *plen, int flag);
extern void xtInitRoot(tid_t tid, struct inode *ip);
extern int xtInsert(tid_t tid, struct inode *ip,
                    int xflag, s64 xoff, int xlen, s64 * xaddrp, int flag);
extern int xtExtend(tid_t tid, struct inode *ip, s64 xoff, int xlen,
                    int flag);
extern int xtUpdate(tid_t tid, struct inode *ip, struct xad *nxad);
extern s64 xtTruncate(tid_t tid, struct inode *ip, s64 newsize, int type);
extern s64 xtTruncate_pmap(tid_t tid, struct inode *ip, s64 committed_size);
extern int xtAppend(tid_t tid,
                    struct inode *ip, int xflag, s64 xoff, int maxblocks,
                    int *xlenp, s64 * xaddrp, int flag);
#endif                          /* !_H_JFS_XTREE */