// SPDX-License-Identifier: GPL-2.0+
/*
 * Copyright (C) 2017 Oracle.  All Rights Reserved.
 * Author: Darrick J. Wong <darrick.wong@oracle.com>
 */
#ifndef __XFS_SCRUB_SCRUB_H__
#define __XFS_SCRUB_SCRUB_H__

struct xfs_scrub;

/* Type info and names for the scrub types. */
enum xchk_type {
        ST_NONE = 1,    /* disabled */
        ST_PERAG,       /* per-AG metadata */
        ST_FS,          /* per-FS metadata */
        ST_INODE,       /* per-inode metadata */
};

struct xchk_meta_ops {
        /* Acquire whatever resources are needed for the operation. */
        int             (*setup)(struct xfs_scrub *sc);

        /* Examine metadata for errors. */
        int             (*scrub)(struct xfs_scrub *);

        /* Repair or optimize the metadata. */
        int             (*repair)(struct xfs_scrub *);

        /* Decide if we even have this piece of metadata. */
        bool            (*has)(struct xfs_mount *);

        /* type describing required/allowed inputs */
        enum xchk_type  type;
};

/* Buffer pointers and btree cursors for an entire AG. */
struct xchk_ag {
        struct xfs_perag        *pag;

        /* AG btree roots */
        struct xfs_buf          *agf_bp;
        struct xfs_buf          *agfl_bp;
        struct xfs_buf          *agi_bp;

        /* AG btrees */
        struct xfs_btree_cur    *bno_cur;
        struct xfs_btree_cur    *cnt_cur;
        struct xfs_btree_cur    *ino_cur;
        struct xfs_btree_cur    *fino_cur;
        struct xfs_btree_cur    *rmap_cur;
        struct xfs_btree_cur    *refc_cur;
};

struct xfs_scrub {
        /* General scrub state. */
        struct xfs_mount                *mp;
        struct xfs_scrub_metadata       *sm;
        const struct xchk_meta_ops      *ops;
        struct xfs_trans                *tp;

        /* File that scrub was called with. */
        struct file                     *file;

        /*
         * File that is undergoing the scrub operation.  This can differ from
         * the file that scrub was called with if we're checking file-based fs
         * metadata (e.g. rt bitmaps) or if we're doing a scrub-by-handle for
         * something that can't be opened directly (e.g. symlinks).
         */
        struct xfs_inode                *ip;

        void                            *buf;
        uint                            ilock_flags;

        /* See the XCHK/XREP state flags below. */
        unsigned int                    flags;

        /*
         * The XFS_SICK_* flags that correspond to the metadata being scrubbed
         * or repaired.  We will use this mask to update the in-core fs health
         * status with whatever we find.
         */
        unsigned int                    sick_mask;

        /* State tracking for single-AG operations. */
        struct xchk_ag                  sa;
};

/* XCHK state flags grow up from zero, XREP state flags grown down from 2^31 */
#define XCHK_TRY_HARDER         (1 << 0)  /* can't get resources, try again */
#define XCHK_HAS_QUOTAOFFLOCK   (1 << 1)  /* we hold the quotaoff lock */
#define XCHK_REAPING_DISABLED   (1 << 2)  /* background block reaping paused */
#define XREP_ALREADY_FIXED      (1 << 31) /* checking our repair work */

/* Metadata scrubbers */
int xchk_tester(struct xfs_scrub *sc);
int xchk_superblock(struct xfs_scrub *sc);
int xchk_agf(struct xfs_scrub *sc);
int xchk_agfl(struct xfs_scrub *sc);
int xchk_agi(struct xfs_scrub *sc);
int xchk_bnobt(struct xfs_scrub *sc);
int xchk_cntbt(struct xfs_scrub *sc);
int xchk_inobt(struct xfs_scrub *sc);
int xchk_finobt(struct xfs_scrub *sc);
int xchk_rmapbt(struct xfs_scrub *sc);
int xchk_refcountbt(struct xfs_scrub *sc);
int xchk_inode(struct xfs_scrub *sc);
int xchk_bmap_data(struct xfs_scrub *sc);
int xchk_bmap_attr(struct xfs_scrub *sc);
int xchk_bmap_cow(struct xfs_scrub *sc);
int xchk_directory(struct xfs_scrub *sc);
int xchk_xattr(struct xfs_scrub *sc);
int xchk_symlink(struct xfs_scrub *sc);
int xchk_parent(struct xfs_scrub *sc);
#ifdef CONFIG_XFS_RT
int xchk_rtbitmap(struct xfs_scrub *sc);
int xchk_rtsummary(struct xfs_scrub *sc);
#else
static inline int
xchk_rtbitmap(struct xfs_scrub *sc)
{
        return -ENOENT;
}
static inline int
xchk_rtsummary(struct xfs_scrub *sc)
{
        return -ENOENT;
}
#endif
#ifdef CONFIG_XFS_QUOTA
int xchk_quota(struct xfs_scrub *sc);
#else
static inline int
xchk_quota(struct xfs_scrub *sc)
{
        return -ENOENT;
}
#endif
int xchk_fscounters(struct xfs_scrub *sc);

/* cross-referencing helpers */
void xchk_xref_is_used_space(struct xfs_scrub *sc, xfs_agblock_t agbno,
                xfs_extlen_t len);
void xchk_xref_is_not_inode_chunk(struct xfs_scrub *sc, xfs_agblock_t agbno,
                xfs_extlen_t len);
void xchk_xref_is_inode_chunk(struct xfs_scrub *sc, xfs_agblock_t agbno,
                xfs_extlen_t len);
void xchk_xref_is_owned_by(struct xfs_scrub *sc, xfs_agblock_t agbno,
                xfs_extlen_t len, const struct xfs_owner_info *oinfo);
void xchk_xref_is_not_owned_by(struct xfs_scrub *sc, xfs_agblock_t agbno,
                xfs_extlen_t len, const struct xfs_owner_info *oinfo);
void xchk_xref_has_no_owner(struct xfs_scrub *sc, xfs_agblock_t agbno,
                xfs_extlen_t len);
void xchk_xref_is_cow_staging(struct xfs_scrub *sc, xfs_agblock_t bno,
                xfs_extlen_t len);
void xchk_xref_is_not_shared(struct xfs_scrub *sc, xfs_agblock_t bno,
                xfs_extlen_t len);
#ifdef CONFIG_XFS_RT
void xchk_xref_is_used_rt_space(struct xfs_scrub *sc, xfs_rtblock_t rtbno,
                xfs_extlen_t len);
#else
# define xchk_xref_is_used_rt_space(sc, rtbno, len) do { } while (0)
#endif

struct xchk_fscounters {
        uint64_t                icount;
        uint64_t                ifree;
        uint64_t                fdblocks;
        unsigned long long      icount_min;
        unsigned long long      icount_max;
};

#endif  /* __XFS_SCRUB_SCRUB_H__ */