// SPDX-License-Identifier: GPL-2.0
/*
 * Copyright (c) 2000-2006 Silicon Graphics, Inc.
 * All Rights Reserved.
 */
#include "xfs_platform.h"
#include "xfs_fs.h"
#include "xfs_shared.h"
#include "xfs_format.h"
#include "xfs_log_format.h"
#include "xfs_trans_resv.h"
#include "xfs_mount.h"
#include "xfs_ag.h"
#include "xfs_inode.h"
#include "xfs_errortag.h"
#include "xfs_error.h"
#include "xfs_icache.h"
#include "xfs_trans.h"
#include "xfs_ialloc.h"
#include "xfs_dir2.h"
#include "xfs_health.h"
#include "xfs_metafile.h"

#include <linux/iversion.h>

/*
 * If we are doing readahead on an inode buffer, we might be in log recovery
 * reading an inode allocation buffer that hasn't yet been replayed, and hence
 * has not had the inode cores stamped into it. Hence for readahead, the buffer
 * may be potentially invalid.
 *
 * If the readahead buffer is invalid, we need to mark it with an error and
 * clear the DONE status of the buffer so that a followup read will re-read it
 * from disk. We don't report the error otherwise to avoid warnings during log
 * recovery and we don't get unnecessary panics on debug kernels. We use EIO here
 * because all we want to do is say readahead failed; there is no-one to report
 * the error to, so this will distinguish it from a non-ra verifier failure.
 * Changes to this readahead error behaviour also need to be reflected in
 * xfs_dquot_buf_readahead_verify().
 */
static void
xfs_inode_buf_verify(
        struct xfs_buf  *bp,
        bool            readahead)
{
        struct xfs_mount *mp = bp->b_mount;
        int             i;
        int             ni;

        /*
         * Validate the magic number and version of every inode in the buffer
         */
        ni = XFS_BB_TO_FSB(mp, bp->b_length) * mp->m_sb.sb_inopblock;
        for (i = 0; i < ni; i++) {
                struct xfs_dinode       *dip;
                xfs_agino_t             unlinked_ino;
                int                     di_ok;

                dip = xfs_buf_offset(bp, (i << mp->m_sb.sb_inodelog));
                unlinked_ino = be32_to_cpu(dip->di_next_unlinked);
                di_ok = xfs_verify_magic16(bp, dip->di_magic) &&
                        xfs_dinode_good_version(mp, dip->di_version) &&
                        xfs_verify_agino_or_null(bp->b_pag, unlinked_ino);
                if (unlikely(!di_ok ||
                                XFS_TEST_ERROR(mp, XFS_ERRTAG_ITOBP_INOTOBP))) {
                        if (readahead) {
                                bp->b_flags &= ~XBF_DONE;
                                xfs_buf_ioerror(bp, -EIO);
                                return;
                        }

#ifdef DEBUG
                        xfs_alert(mp,
                                "bad inode magic/vsn daddr %lld #%d (magic=%x)",
                                (unsigned long long)xfs_buf_daddr(bp), i,
                                be16_to_cpu(dip->di_magic));
#endif
                        xfs_buf_verifier_error(bp, -EFSCORRUPTED,
                                        __func__, dip, sizeof(*dip),
                                        NULL);
                        return;
                }
        }
}


static void
xfs_inode_buf_read_verify(
        struct xfs_buf  *bp)
{
        xfs_inode_buf_verify(bp, false);
}

static void
xfs_inode_buf_readahead_verify(
        struct xfs_buf  *bp)
{
        xfs_inode_buf_verify(bp, true);
}

static void
xfs_inode_buf_write_verify(
        struct xfs_buf  *bp)
{
        xfs_inode_buf_verify(bp, false);
}

const struct xfs_buf_ops xfs_inode_buf_ops = {
        .name = "xfs_inode",
        .magic16 = { cpu_to_be16(XFS_DINODE_MAGIC),
                     cpu_to_be16(XFS_DINODE_MAGIC) },
        .verify_read = xfs_inode_buf_read_verify,
        .verify_write = xfs_inode_buf_write_verify,
};

const struct xfs_buf_ops xfs_inode_buf_ra_ops = {
        .name = "xfs_inode_ra",
        .magic16 = { cpu_to_be16(XFS_DINODE_MAGIC),
                     cpu_to_be16(XFS_DINODE_MAGIC) },
        .verify_read = xfs_inode_buf_readahead_verify,
        .verify_write = xfs_inode_buf_write_verify,
};


/*
 * This routine is called to map an inode to the buffer containing the on-disk
 * version of the inode.  It returns a pointer to the buffer containing the
 * on-disk inode in the bpp parameter.
 */
int
xfs_imap_to_bp(
        struct xfs_mount        *mp,
        struct xfs_trans        *tp,
        struct xfs_imap         *imap,
        struct xfs_buf          **bpp)
{
        int                     error;

        error = xfs_trans_read_buf(mp, tp, mp->m_ddev_targp, imap->im_blkno,
                        imap->im_len, 0, bpp, &xfs_inode_buf_ops);
        if (xfs_metadata_is_sick(error))
                xfs_agno_mark_sick(mp, xfs_daddr_to_agno(mp, imap->im_blkno),
                                XFS_SICK_AG_INODES);
        return error;
}

static inline struct timespec64 xfs_inode_decode_bigtime(uint64_t ts)
{
        struct timespec64       tv;
        uint32_t                n;

        tv.tv_sec = xfs_bigtime_to_unix(div_u64_rem(ts, NSEC_PER_SEC, &n));
        tv.tv_nsec = n;

        return tv;
}

/* Convert an ondisk timestamp to an incore timestamp. */
struct timespec64
xfs_inode_from_disk_ts(
        struct xfs_dinode               *dip,
        const xfs_timestamp_t           ts)
{
        struct timespec64               tv;
        struct xfs_legacy_timestamp     *lts;

        if (xfs_dinode_has_bigtime(dip))
                return xfs_inode_decode_bigtime(be64_to_cpu(ts));

        lts = (struct xfs_legacy_timestamp *)&ts;
        tv.tv_sec = (int)be32_to_cpu(lts->t_sec);
        tv.tv_nsec = (int)be32_to_cpu(lts->t_nsec);

        return tv;
}

int
xfs_inode_from_disk(
        struct xfs_inode        *ip,
        struct xfs_dinode       *from)
{
        struct inode            *inode = VFS_I(ip);
        int                     error;
        xfs_failaddr_t          fa;

        ASSERT(ip->i_cowfp == NULL);

        fa = xfs_dinode_verify(ip->i_mount, ip->i_ino, from);
        if (fa) {
                xfs_inode_verifier_error(ip, -EFSCORRUPTED, "dinode", from,
                                sizeof(*from), fa);
                return -EFSCORRUPTED;
        }

        /*
         * First get the permanent information that is needed to allocate an
         * inode. If the inode is unused, mode is zero and we shouldn't mess
         * with the uninitialized part of it.
         */
        if (!xfs_has_v3inodes(ip->i_mount))
                ip->i_flushiter = be16_to_cpu(from->di_flushiter);
        inode->i_generation = be32_to_cpu(from->di_gen);
        inode->i_mode = be16_to_cpu(from->di_mode);
        if (!inode->i_mode)
                return 0;

        /*
         * Convert v1 inodes immediately to v2 inode format as this is the
         * minimum inode version format we support in the rest of the code.
         * They will also be unconditionally written back to disk as v2 inodes.
         */
        if (unlikely(from->di_version == 1)) {
                /* di_metatype used to be di_onlink */
                set_nlink(inode, be16_to_cpu(from->di_metatype));
                ip->i_projid = 0;
        } else {
                set_nlink(inode, be32_to_cpu(from->di_nlink));
                ip->i_projid = (prid_t)be16_to_cpu(from->di_projid_hi) << 16 |
                                        be16_to_cpu(from->di_projid_lo);
                if (xfs_dinode_is_metadir(from))
                        ip->i_metatype = be16_to_cpu(from->di_metatype);
        }

        i_uid_write(inode, be32_to_cpu(from->di_uid));
        i_gid_write(inode, be32_to_cpu(from->di_gid));

        /*
         * Time is signed, so need to convert to signed 32 bit before
         * storing in inode timestamp which may be 64 bit. Otherwise
         * a time before epoch is converted to a time long after epoch
         * on 64 bit systems.
         */
        inode_set_atime_to_ts(inode,
                              xfs_inode_from_disk_ts(from, from->di_atime));
        inode_set_mtime_to_ts(inode,
                              xfs_inode_from_disk_ts(from, from->di_mtime));
        inode_set_ctime_to_ts(inode,
                              xfs_inode_from_disk_ts(from, from->di_ctime));

        ip->i_disk_size = be64_to_cpu(from->di_size);
        ip->i_nblocks = be64_to_cpu(from->di_nblocks);
        ip->i_extsize = be32_to_cpu(from->di_extsize);
        ip->i_forkoff = from->di_forkoff;
        ip->i_diflags = be16_to_cpu(from->di_flags);
        ip->i_next_unlinked = be32_to_cpu(from->di_next_unlinked);

        if (from->di_dmevmask || from->di_dmstate)
                xfs_iflags_set(ip, XFS_IPRESERVE_DM_FIELDS);

        if (xfs_has_v3inodes(ip->i_mount)) {
                inode_set_iversion_queried(inode,
                                           be64_to_cpu(from->di_changecount));
                ip->i_crtime = xfs_inode_from_disk_ts(from, from->di_crtime);
                ip->i_diflags2 = be64_to_cpu(from->di_flags2);
                /* also covers the di_used_blocks union arm: */
                ip->i_cowextsize = be32_to_cpu(from->di_cowextsize);
                BUILD_BUG_ON(sizeof(from->di_cowextsize) !=
                             sizeof(from->di_used_blocks));
        }

        error = xfs_iformat_data_fork(ip, from);
        if (error)
                return error;
        if (from->di_forkoff) {
                error = xfs_iformat_attr_fork(ip, from);
                if (error)
                        goto out_destroy_data_fork;
        }
        if (xfs_is_reflink_inode(ip))
                xfs_ifork_init_cow(ip);
        if (xfs_is_metadir_inode(ip)) {
                XFS_STATS_DEC(ip->i_mount, xs_inodes_active);
                XFS_STATS_INC(ip->i_mount, xs_inodes_meta);
        }
        return 0;

out_destroy_data_fork:
        xfs_idestroy_fork(&ip->i_df);
        return error;
}

/* Convert an incore timestamp to an ondisk timestamp. */
static inline xfs_timestamp_t
xfs_inode_to_disk_ts(
        struct xfs_inode                *ip,
        const struct timespec64         tv)
{
        struct xfs_legacy_timestamp     *lts;
        xfs_timestamp_t                 ts;

        if (xfs_inode_has_bigtime(ip))
                return cpu_to_be64(xfs_inode_encode_bigtime(tv));

        lts = (struct xfs_legacy_timestamp *)&ts;
        lts->t_sec = cpu_to_be32(tv.tv_sec);
        lts->t_nsec = cpu_to_be32(tv.tv_nsec);

        return ts;
}

static inline void
xfs_inode_to_disk_iext_counters(
        struct xfs_inode        *ip,
        struct xfs_dinode       *to)
{
        if (xfs_inode_has_large_extent_counts(ip)) {
                to->di_big_nextents = cpu_to_be64(xfs_ifork_nextents(&ip->i_df));
                to->di_big_anextents = cpu_to_be32(xfs_ifork_nextents(&ip->i_af));
                /*
                 * We might be upgrading the inode to use larger extent counters
                 * than was previously used. Hence zero the unused field.
                 */
                to->di_nrext64_pad = cpu_to_be16(0);
        } else {
                to->di_nextents = cpu_to_be32(xfs_ifork_nextents(&ip->i_df));
                to->di_anextents = cpu_to_be16(xfs_ifork_nextents(&ip->i_af));
        }
}

void
xfs_inode_to_disk(
        struct xfs_inode        *ip,
        struct xfs_dinode       *to,
        xfs_lsn_t               lsn)
{
        struct inode            *inode = VFS_I(ip);

        to->di_magic = cpu_to_be16(XFS_DINODE_MAGIC);
        if (xfs_is_metadir_inode(ip))
                to->di_metatype = cpu_to_be16(ip->i_metatype);
        else
                to->di_metatype = 0;

        to->di_format = xfs_ifork_format(&ip->i_df);
        to->di_uid = cpu_to_be32(i_uid_read(inode));
        to->di_gid = cpu_to_be32(i_gid_read(inode));
        to->di_projid_lo = cpu_to_be16(ip->i_projid & 0xffff);
        to->di_projid_hi = cpu_to_be16(ip->i_projid >> 16);

        to->di_atime = xfs_inode_to_disk_ts(ip, inode_get_atime(inode));
        to->di_mtime = xfs_inode_to_disk_ts(ip, inode_get_mtime(inode));
        to->di_ctime = xfs_inode_to_disk_ts(ip, inode_get_ctime(inode));
        to->di_nlink = cpu_to_be32(inode->i_nlink);
        to->di_gen = cpu_to_be32(inode->i_generation);
        to->di_mode = cpu_to_be16(inode->i_mode);

        to->di_size = cpu_to_be64(ip->i_disk_size);
        to->di_nblocks = cpu_to_be64(ip->i_nblocks);
        to->di_extsize = cpu_to_be32(ip->i_extsize);
        to->di_forkoff = ip->i_forkoff;
        to->di_aformat = xfs_ifork_format(&ip->i_af);
        to->di_flags = cpu_to_be16(ip->i_diflags);

        if (xfs_has_v3inodes(ip->i_mount)) {
                to->di_version = 3;
                to->di_changecount = cpu_to_be64(inode_peek_iversion(inode));
                to->di_crtime = xfs_inode_to_disk_ts(ip, ip->i_crtime);
                to->di_flags2 = cpu_to_be64(ip->i_diflags2);
                /* also covers the di_used_blocks union arm: */
                to->di_cowextsize = cpu_to_be32(ip->i_cowextsize);
                to->di_ino = cpu_to_be64(ip->i_ino);
                to->di_lsn = cpu_to_be64(lsn);
                memset(to->di_pad2, 0, sizeof(to->di_pad2));
                uuid_copy(&to->di_uuid, &ip->i_mount->m_sb.sb_meta_uuid);
                to->di_v3_pad = 0;
        } else {
                to->di_version = 2;
                to->di_flushiter = cpu_to_be16(ip->i_flushiter);
                memset(to->di_v2_pad, 0, sizeof(to->di_v2_pad));
        }

        xfs_inode_to_disk_iext_counters(ip, to);
}

static xfs_failaddr_t
xfs_dinode_verify_fork(
        struct xfs_dinode       *dip,
        struct xfs_mount        *mp,
        int                     whichfork)
{
        xfs_extnum_t            di_nextents;
        xfs_extnum_t            max_extents;
        mode_t                  mode = be16_to_cpu(dip->di_mode);
        uint32_t                fork_size = XFS_DFORK_SIZE(dip, mp, whichfork);
        uint32_t                fork_format = XFS_DFORK_FORMAT(dip, whichfork);

        di_nextents = xfs_dfork_nextents(dip, whichfork);

        /*
         * For fork types that can contain local data, check that the fork
         * format matches the size of local data contained within the fork.
         */
        if (whichfork == XFS_DATA_FORK) {
                /*
                 * A directory small enough to fit in the inode must be stored
                 * in local format.  The directory sf <-> extents conversion
                 * code updates the directory size accordingly.  Directories
                 * being truncated have zero size and are not subject to this
                 * check.
                 */
                if (S_ISDIR(mode)) {
                        if (dip->di_size &&
                            be64_to_cpu(dip->di_size) <= fork_size &&
                            fork_format != XFS_DINODE_FMT_LOCAL)
                                return __this_address;
                }

                /*
                 * A symlink with a target small enough to fit in the inode can
                 * be stored in extents format if xattrs were added (thus
                 * converting the data fork from shortform to remote format)
                 * and then removed.
                 */
                if (S_ISLNK(mode)) {
                        if (be64_to_cpu(dip->di_size) <= fork_size &&
                            fork_format != XFS_DINODE_FMT_EXTENTS &&
                            fork_format != XFS_DINODE_FMT_LOCAL)
                                return __this_address;
                }

                /*
                 * For all types, check that when the size says the fork should
                 * be in extent or btree format, the inode isn't claiming to be
                 * in local format.
                 */
                if (be64_to_cpu(dip->di_size) > fork_size &&
                    fork_format == XFS_DINODE_FMT_LOCAL)
                        return __this_address;
        }

        switch (fork_format) {
        case XFS_DINODE_FMT_LOCAL:
                /*
                 * No local regular files yet.
                 */
                if (S_ISREG(mode) && whichfork == XFS_DATA_FORK)
                        return __this_address;
                if (di_nextents)
                        return __this_address;
                break;
        case XFS_DINODE_FMT_EXTENTS:
                if (di_nextents > XFS_DFORK_MAXEXT(dip, mp, whichfork))
                        return __this_address;
                break;
        case XFS_DINODE_FMT_BTREE:
                max_extents = xfs_iext_max_nextents(
                                        xfs_dinode_has_large_extent_counts(dip),
                                        whichfork);
                if (di_nextents > max_extents)
                        return __this_address;
                break;
        case XFS_DINODE_FMT_META_BTREE:
                if (!xfs_has_metadir(mp))
                        return __this_address;
                if (!(dip->di_flags2 & cpu_to_be64(XFS_DIFLAG2_METADATA)))
                        return __this_address;
                switch (be16_to_cpu(dip->di_metatype)) {
                case XFS_METAFILE_RTRMAP:
                        /*
                         * growfs must create the rtrmap inodes before adding a
                         * realtime volume to the filesystem, so we cannot use
                         * the rtrmapbt predicate here.
                         */
                        if (!xfs_has_rmapbt(mp))
                                return __this_address;
                        break;
                case XFS_METAFILE_RTREFCOUNT:
                        /* same comment about growfs and rmap inodes applies */
                        if (!xfs_has_reflink(mp))
                                return __this_address;
                        break;
                default:
                        return __this_address;
                }
                break;
        default:
                return __this_address;
        }
        return NULL;
}

static xfs_failaddr_t
xfs_dinode_verify_forkoff(
        struct xfs_dinode       *dip,
        struct xfs_mount        *mp)
{
        if (!dip->di_forkoff)
                return NULL;

        switch (dip->di_format)  {
        case XFS_DINODE_FMT_DEV:
                if (dip->di_forkoff != (roundup(sizeof(xfs_dev_t), 8) >> 3))
                        return __this_address;
                break;
        case XFS_DINODE_FMT_META_BTREE:
                if (!xfs_has_metadir(mp) || !xfs_has_parent(mp))
                        return __this_address;
                fallthrough;
        case XFS_DINODE_FMT_LOCAL:      /* fall through ... */
        case XFS_DINODE_FMT_EXTENTS:    /* fall through ... */
        case XFS_DINODE_FMT_BTREE:
                if (dip->di_forkoff >= (XFS_LITINO(mp) >> 3))
                        return __this_address;
                break;
        default:
                return __this_address;
        }
        return NULL;
}

static xfs_failaddr_t
xfs_dinode_verify_nrext64(
        struct xfs_mount        *mp,
        struct xfs_dinode       *dip)
{
        if (xfs_dinode_has_large_extent_counts(dip)) {
                if (!xfs_has_large_extent_counts(mp))
                        return __this_address;
                if (dip->di_nrext64_pad != 0)
                        return __this_address;
        } else if (dip->di_version >= 3) {
                if (dip->di_v3_pad != 0)
                        return __this_address;
        }

        return NULL;
}

/*
 * Validate all the picky requirements we have for a file that claims to be
 * filesystem metadata.
 */
xfs_failaddr_t
xfs_dinode_verify_metadir(
        struct xfs_mount        *mp,
        struct xfs_dinode       *dip,
        uint16_t                mode,
        uint16_t                flags,
        uint64_t                flags2)
{
        if (!xfs_has_metadir(mp))
                return __this_address;

        /* V5 filesystem only */
        if (dip->di_version < 3)
                return __this_address;

        if (be16_to_cpu(dip->di_metatype) >= XFS_METAFILE_MAX)
                return __this_address;

        /* V3 inode fields that are always zero */
        if ((flags2 & XFS_DIFLAG2_NREXT64) && dip->di_nrext64_pad)
                return __this_address;
        if (!(flags2 & XFS_DIFLAG2_NREXT64) && dip->di_flushiter)
                return __this_address;

        /* Metadata files can only be directories or regular files */
        if (!S_ISDIR(mode) && !S_ISREG(mode))
                return __this_address;

        /* They must have zero access permissions */
        if (mode & 0777)
                return __this_address;

        /* DMAPI event and state masks are zero */
        if (dip->di_dmevmask || dip->di_dmstate)
                return __this_address;

        /*
         * User and group IDs must be zero.  The project ID is used for
         * grouping inodes.  Metadata inodes are never accounted to quotas.
         */
        if (dip->di_uid || dip->di_gid)
                return __this_address;

        /* Mandatory inode flags must be set */
        if (S_ISDIR(mode)) {
                if ((flags & XFS_METADIR_DIFLAGS) != XFS_METADIR_DIFLAGS)
                        return __this_address;
        } else {
                if ((flags & XFS_METAFILE_DIFLAGS) != XFS_METAFILE_DIFLAGS)
                        return __this_address;
        }

        /* dax flags2 must not be set */
        if (flags2 & XFS_DIFLAG2_DAX)
                return __this_address;

        return NULL;
}

xfs_failaddr_t
xfs_dinode_verify(
        struct xfs_mount        *mp,
        xfs_ino_t               ino,
        struct xfs_dinode       *dip)
{
        xfs_failaddr_t          fa;
        uint16_t                mode;
        uint16_t                flags;
        uint64_t                flags2;
        uint64_t                di_size;
        xfs_extnum_t            nextents;
        xfs_extnum_t            naextents;
        xfs_filblks_t           nblocks;

        if (dip->di_magic != cpu_to_be16(XFS_DINODE_MAGIC))
                return __this_address;

        /* Verify v3 integrity information first */
        if (dip->di_version >= 3) {
                if (!xfs_has_v3inodes(mp))
                        return __this_address;
                if (!xfs_verify_cksum((char *)dip, mp->m_sb.sb_inodesize,
                                      XFS_DINODE_CRC_OFF))
                        return __this_address;
                if (be64_to_cpu(dip->di_ino) != ino)
                        return __this_address;
                if (!uuid_equal(&dip->di_uuid, &mp->m_sb.sb_meta_uuid))
                        return __this_address;
        }

        /*
         * Historical note: xfsprogs in the 3.2 era set up its incore inodes to
         * have di_nlink track the link count, even if the actual filesystem
         * only supported V1 inodes (i.e. di_onlink).  When writing out the
         * ondisk inode, it would set both the ondisk di_nlink and di_onlink to
         * the the incore di_nlink value, which is why we cannot check for
         * di_nlink==0 on a V1 inode.  V2/3 inodes would get written out with
         * di_onlink==0, so we can check that.
         */
        if (dip->di_version == 2) {
                if (dip->di_metatype)
                        return __this_address;
        } else if (dip->di_version >= 3) {
                if (!xfs_dinode_is_metadir(dip) && dip->di_metatype)
                        return __this_address;
        }

        /* don't allow invalid i_size */
        di_size = be64_to_cpu(dip->di_size);
        if (di_size & (1ULL << 63))
                return __this_address;

        mode = be16_to_cpu(dip->di_mode);
        if (mode && xfs_mode_to_ftype(mode) == XFS_DIR3_FT_UNKNOWN)
                return __this_address;

        /*
         * No zero-length symlinks/dirs unless they're unlinked and hence being
         * inactivated.
         */
        if ((S_ISLNK(mode) || S_ISDIR(mode)) && di_size == 0) {
                if (dip->di_version > 1) {
                        if (dip->di_nlink)
                                return __this_address;
                } else {
                        /* di_metatype used to be di_onlink */
                        if (dip->di_metatype)
                                return __this_address;
                }
        }

        fa = xfs_dinode_verify_nrext64(mp, dip);
        if (fa)
                return fa;

        nextents = xfs_dfork_data_extents(dip);
        naextents = xfs_dfork_attr_extents(dip);
        nblocks = be64_to_cpu(dip->di_nblocks);

        /* Fork checks carried over from xfs_iformat_fork */
        if (mode && nextents + naextents > nblocks)
                return __this_address;

        if (S_ISDIR(mode) && nextents > mp->m_dir_geo->max_extents)
                return __this_address;

        if (mode && XFS_DFORK_BOFF(dip) > mp->m_sb.sb_inodesize)
                return __this_address;

        flags = be16_to_cpu(dip->di_flags);

        if (mode && (flags & XFS_DIFLAG_REALTIME) && !mp->m_rtdev_targp)
                return __this_address;

        /* check for illegal values of forkoff */
        fa = xfs_dinode_verify_forkoff(dip, mp);
        if (fa)
                return fa;

        /* Do we have appropriate data fork formats for the mode? */
        switch (mode & S_IFMT) {
        case S_IFIFO:
        case S_IFCHR:
        case S_IFBLK:
        case S_IFSOCK:
                if (dip->di_format != XFS_DINODE_FMT_DEV)
                        return __this_address;
                break;
        case S_IFREG:
        case S_IFLNK:
        case S_IFDIR:
                fa = xfs_dinode_verify_fork(dip, mp, XFS_DATA_FORK);
                if (fa)
                        return fa;
                break;
        case 0:
                /* Uninitialized inode ok. */
                break;
        default:
                return __this_address;
        }

        if (dip->di_forkoff) {
                fa = xfs_dinode_verify_fork(dip, mp, XFS_ATTR_FORK);
                if (fa)
                        return fa;
        } else {
                /*
                 * If there is no fork offset, this may be a freshly-made inode
                 * in a new disk cluster, in which case di_aformat is zeroed.
                 * Otherwise, such an inode must be in EXTENTS format; this goes
                 * for freed inodes as well.
                 */
                switch (dip->di_aformat) {
                case 0:
                case XFS_DINODE_FMT_EXTENTS:
                        break;
                default:
                        return __this_address;
                }
                if (naextents)
                        return __this_address;
        }

        /* extent size hint validation */
        fa = xfs_inode_validate_extsize(mp, be32_to_cpu(dip->di_extsize),
                        mode, flags);
        if (fa)
                return fa;

        /* only version 3 or greater inodes are extensively verified here */
        if (dip->di_version < 3)
                return NULL;

        flags2 = be64_to_cpu(dip->di_flags2);

        /* don't allow reflink/cowextsize if we don't have reflink */
        if ((flags2 & (XFS_DIFLAG2_REFLINK | XFS_DIFLAG2_COWEXTSIZE)) &&
             !xfs_has_reflink(mp))
                return __this_address;

        /* only regular files get reflink */
        if ((flags2 & XFS_DIFLAG2_REFLINK) && (mode & S_IFMT) != S_IFREG)
                return __this_address;

        /* don't let reflink and realtime mix */
        if ((flags2 & XFS_DIFLAG2_REFLINK) && (flags & XFS_DIFLAG_REALTIME) &&
            !xfs_has_rtreflink(mp))
                return __this_address;

        if (xfs_has_zoned(mp) &&
            dip->di_metatype == cpu_to_be16(XFS_METAFILE_RTRMAP)) {
                if (be32_to_cpu(dip->di_used_blocks) > mp->m_sb.sb_rgextents)
                        return __this_address;
        } else {
                /* COW extent size hint validation */
                fa = xfs_inode_validate_cowextsize(mp,
                                be32_to_cpu(dip->di_cowextsize),
                                mode, flags, flags2);
                if (fa)
                        return fa;
        }

        /* bigtime iflag can only happen on bigtime filesystems */
        if (xfs_dinode_has_bigtime(dip) &&
            !xfs_has_bigtime(mp))
                return __this_address;

        if (flags2 & XFS_DIFLAG2_METADATA) {
                fa = xfs_dinode_verify_metadir(mp, dip, mode, flags, flags2);
                if (fa)
                        return fa;
        }

        /* metadata inodes containing btrees always have zero extent count */
        if (XFS_DFORK_FORMAT(dip, XFS_DATA_FORK) != XFS_DINODE_FMT_META_BTREE) {
                if (nextents + naextents == 0 && nblocks != 0)
                        return __this_address;
        }

        return NULL;
}

void
xfs_dinode_calc_crc(
        struct xfs_mount        *mp,
        struct xfs_dinode       *dip)
{
        uint32_t                crc;

        if (dip->di_version < 3)
                return;

        ASSERT(xfs_has_crc(mp));
        crc = xfs_start_cksum_update((char *)dip, mp->m_sb.sb_inodesize,
                              XFS_DINODE_CRC_OFF);
        dip->di_crc = xfs_end_cksum(crc);
}

/*
 * Validate di_extsize hint.
 *
 * 1. Extent size hint is only valid for directories and regular files.
 * 2. FS_XFLAG_EXTSIZE is only valid for regular files.
 * 3. FS_XFLAG_EXTSZINHERIT is only valid for directories.
 * 4. Hint cannot be larger than MAXTEXTLEN.
 * 5. Can be changed on directories at any time.
 * 6. Hint value of 0 turns off hints, clears inode flags.
 * 7. Extent size must be a multiple of the appropriate block size.
 *    For realtime files, this is the rt extent size.
 * 8. For non-realtime files, the extent size hint must be limited
 *    to half the AG size to avoid alignment extending the extent beyond the
 *    limits of the AG.
 */
xfs_failaddr_t
xfs_inode_validate_extsize(
        struct xfs_mount                *mp,
        uint32_t                        extsize,
        uint16_t                        mode,
        uint16_t                        flags)
{
        bool                            rt_flag;
        bool                            hint_flag;
        bool                            inherit_flag;
        uint32_t                        extsize_bytes;
        uint32_t                        blocksize_bytes;

        rt_flag = (flags & XFS_DIFLAG_REALTIME);
        hint_flag = (flags & XFS_DIFLAG_EXTSIZE);
        inherit_flag = (flags & XFS_DIFLAG_EXTSZINHERIT);
        extsize_bytes = XFS_FSB_TO_B(mp, extsize);

        /*
         * This comment describes a historic gap in this verifier function.
         *
         * For a directory with both RTINHERIT and EXTSZINHERIT flags set, this
         * function has never checked that the extent size hint is an integer
         * multiple of the realtime extent size.  Since we allow users to set
         * this combination  on non-rt filesystems /and/ to change the rt
         * extent size when adding a rt device to a filesystem, the net effect
         * is that users can configure a filesystem anticipating one rt
         * geometry and change their minds later.  Directories do not use the
         * extent size hint, so this is harmless for them.
         *
         * If a directory with a misaligned extent size hint is allowed to
         * propagate that hint into a new regular realtime file, the result
         * is that the inode cluster buffer verifier will trigger a corruption
         * shutdown the next time it is run, because the verifier has always
         * enforced the alignment rule for regular files.
         *
         * Because we allow administrators to set a new rt extent size when
         * adding a rt section, we cannot add a check to this verifier because
         * that will result a new source of directory corruption errors when
         * reading an existing filesystem.  Instead, we rely on callers to
         * decide when alignment checks are appropriate, and fix things up as
         * needed.
         */

        if (rt_flag)
                blocksize_bytes = XFS_FSB_TO_B(mp, mp->m_sb.sb_rextsize);
        else
                blocksize_bytes = mp->m_sb.sb_blocksize;

        if ((hint_flag || inherit_flag) && !(S_ISDIR(mode) || S_ISREG(mode)))
                return __this_address;

        if (hint_flag && !S_ISREG(mode))
                return __this_address;

        if (inherit_flag && !S_ISDIR(mode))
                return __this_address;

        if ((hint_flag || inherit_flag) && extsize == 0)
                return __this_address;

        /* free inodes get flags set to zero but extsize remains */
        if (mode && !(hint_flag || inherit_flag) && extsize != 0)
                return __this_address;

        if (extsize_bytes % blocksize_bytes)
                return __this_address;

        if (extsize > XFS_MAX_BMBT_EXTLEN)
                return __this_address;

        if (!rt_flag && extsize > mp->m_sb.sb_agblocks / 2)
                return __this_address;

        return NULL;
}

/*
 * Validate di_cowextsize hint.
 *
 * 1. CoW extent size hint can only be set if reflink is enabled on the fs.
 *    The inode does not have to have any shared blocks, but it must be a v3.
 * 2. FS_XFLAG_COWEXTSIZE is only valid for directories and regular files;
 *    for a directory, the hint is propagated to new files.
 * 3. Can be changed on files & directories at any time.
 * 4. Hint value of 0 turns off hints, clears inode flags.
 * 5. Extent size must be a multiple of the appropriate block size.
 * 6. The extent size hint must be limited to half the AG size to avoid
 *    alignment extending the extent beyond the limits of the AG.
 */
xfs_failaddr_t
xfs_inode_validate_cowextsize(
        struct xfs_mount                *mp,
        uint32_t                        cowextsize,
        uint16_t                        mode,
        uint16_t                        flags,
        uint64_t                        flags2)
{
        bool                            rt_flag;
        bool                            hint_flag;
        uint32_t                        cowextsize_bytes;
        uint32_t                        blocksize_bytes;

        rt_flag = (flags & XFS_DIFLAG_REALTIME);
        hint_flag = (flags2 & XFS_DIFLAG2_COWEXTSIZE);
        cowextsize_bytes = XFS_FSB_TO_B(mp, cowextsize);

        /*
         * Similar to extent size hints, a directory can be configured to
         * propagate realtime status and a CoW extent size hint to newly
         * created files even if there is no realtime device, and the hints on
         * disk can become misaligned if the sysadmin changes the rt extent
         * size while adding the realtime device.
         *
         * Therefore, we can only enforce the rextsize alignment check against
         * regular realtime files, and rely on callers to decide when alignment
         * checks are appropriate, and fix things up as needed.
         */

        if (rt_flag)
                blocksize_bytes = XFS_FSB_TO_B(mp, mp->m_sb.sb_rextsize);
        else
                blocksize_bytes = mp->m_sb.sb_blocksize;

        if (hint_flag && !xfs_has_reflink(mp))
                return __this_address;

        if (hint_flag && !(S_ISDIR(mode) || S_ISREG(mode)))
                return __this_address;

        if (hint_flag && cowextsize == 0)
                return __this_address;

        /* free inodes get flags set to zero but cowextsize remains */
        if (mode && !hint_flag && cowextsize != 0)
                return __this_address;

        if (cowextsize_bytes % blocksize_bytes)
                return __this_address;

        if (cowextsize > XFS_MAX_BMBT_EXTLEN)
                return __this_address;

        if (!rt_flag && cowextsize > mp->m_sb.sb_agblocks / 2)
                return __this_address;

        return NULL;
}