// SPDX-License-Identifier: GPL-2.0
/*
 * Copyright (c) 2000-2006 Silicon Graphics, Inc.
 * Copyright (c) 2013 Red Hat, 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_inode.h"
#include "xfs_quota.h"
#include "xfs_trans.h"
#include "xfs_qm.h"
#include "xfs_error.h"
#include "xfs_health.h"
#include "xfs_metadir.h"
#include "xfs_metafile.h"

int
xfs_calc_dquots_per_chunk(
        unsigned int            nbblks) /* basic block units */
{
        ASSERT(nbblks > 0);
        return BBTOB(nbblks) / sizeof(struct xfs_dqblk);
}

/*
 * Do some primitive error checking on ondisk dquot data structures.
 *
 * The xfs_dqblk structure /contains/ the xfs_disk_dquot structure;
 * we verify them separately because at some points we have only the
 * smaller xfs_disk_dquot structure available.
 */

xfs_failaddr_t
xfs_dquot_verify(
        struct xfs_mount        *mp,
        struct xfs_disk_dquot   *ddq,
        xfs_dqid_t              id)     /* used only during quotacheck */
{
        __u8                    ddq_type;

        /*
         * We can encounter an uninitialized dquot buffer for 2 reasons:
         * 1. If we crash while deleting the quotainode(s), and those blks got
         *    used for user data. This is because we take the path of regular
         *    file deletion; however, the size field of quotainodes is never
         *    updated, so all the tricks that we play in itruncate_finish
         *    don't quite matter.
         *
         * 2. We don't play the quota buffers when there's a quotaoff logitem.
         *    But the allocation will be replayed so we'll end up with an
         *    uninitialized quota block.
         *
         * This is all fine; things are still consistent, and we haven't lost
         * any quota information. Just don't complain about bad dquot blks.
         */
        if (ddq->d_magic != cpu_to_be16(XFS_DQUOT_MAGIC))
                return __this_address;
        if (ddq->d_version != XFS_DQUOT_VERSION)
                return __this_address;

        if (ddq->d_type & ~XFS_DQTYPE_ANY)
                return __this_address;
        ddq_type = ddq->d_type & XFS_DQTYPE_REC_MASK;
        if (ddq_type != XFS_DQTYPE_USER &&
            ddq_type != XFS_DQTYPE_PROJ &&
            ddq_type != XFS_DQTYPE_GROUP)
                return __this_address;

        if ((ddq->d_type & XFS_DQTYPE_BIGTIME) &&
            !xfs_has_bigtime(mp))
                return __this_address;

        if ((ddq->d_type & XFS_DQTYPE_BIGTIME) && !ddq->d_id)
                return __this_address;

        if (id != -1 && id != be32_to_cpu(ddq->d_id))
                return __this_address;

        if (!ddq->d_id)
                return NULL;

        if (ddq->d_blk_softlimit &&
            be64_to_cpu(ddq->d_bcount) > be64_to_cpu(ddq->d_blk_softlimit) &&
            !ddq->d_btimer)
                return __this_address;

        if (ddq->d_ino_softlimit &&
            be64_to_cpu(ddq->d_icount) > be64_to_cpu(ddq->d_ino_softlimit) &&
            !ddq->d_itimer)
                return __this_address;

        if (ddq->d_rtb_softlimit &&
            be64_to_cpu(ddq->d_rtbcount) > be64_to_cpu(ddq->d_rtb_softlimit) &&
            !ddq->d_rtbtimer)
                return __this_address;

        return NULL;
}

xfs_failaddr_t
xfs_dqblk_verify(
        struct xfs_mount        *mp,
        struct xfs_dqblk        *dqb,
        xfs_dqid_t              id)     /* used only during quotacheck */
{
        if (xfs_has_crc(mp) &&
            !uuid_equal(&dqb->dd_uuid, &mp->m_sb.sb_meta_uuid))
                return __this_address;

        return xfs_dquot_verify(mp, &dqb->dd_diskdq, id);
}

/*
 * Do some primitive error checking on ondisk dquot data structures.
 */
void
xfs_dqblk_repair(
        struct xfs_mount        *mp,
        struct xfs_dqblk        *dqb,
        xfs_dqid_t              id,
        xfs_dqtype_t            type)
{
        /*
         * Typically, a repair is only requested by quotacheck.
         */
        ASSERT(id != -1);
        memset(dqb, 0, sizeof(struct xfs_dqblk));

        dqb->dd_diskdq.d_magic = cpu_to_be16(XFS_DQUOT_MAGIC);
        dqb->dd_diskdq.d_version = XFS_DQUOT_VERSION;
        dqb->dd_diskdq.d_type = type;
        dqb->dd_diskdq.d_id = cpu_to_be32(id);

        if (xfs_has_crc(mp)) {
                uuid_copy(&dqb->dd_uuid, &mp->m_sb.sb_meta_uuid);
                xfs_update_cksum((char *)dqb, sizeof(struct xfs_dqblk),
                                 XFS_DQUOT_CRC_OFF);
        }
}

STATIC bool
xfs_dquot_buf_verify_crc(
        struct xfs_mount        *mp,
        struct xfs_buf          *bp,
        bool                    readahead)
{
        struct xfs_dqblk        *d = (struct xfs_dqblk *)bp->b_addr;
        int                     ndquots;
        int                     i;

        if (!xfs_has_crc(mp))
                return true;

        /*
         * if we are in log recovery, the quota subsystem has not been
         * initialised so we have no quotainfo structure. In that case, we need
         * to manually calculate the number of dquots in the buffer.
         */
        if (mp->m_quotainfo)
                ndquots = mp->m_quotainfo->qi_dqperchunk;
        else
                ndquots = xfs_calc_dquots_per_chunk(bp->b_length);

        for (i = 0; i < ndquots; i++, d++) {
                if (!xfs_verify_cksum((char *)d, sizeof(struct xfs_dqblk),
                                 XFS_DQUOT_CRC_OFF)) {
                        if (!readahead)
                                xfs_buf_verifier_error(bp, -EFSBADCRC, __func__,
                                        d, sizeof(*d), __this_address);
                        return false;
                }
        }
        return true;
}

STATIC xfs_failaddr_t
xfs_dquot_buf_verify(
        struct xfs_mount        *mp,
        struct xfs_buf          *bp,
        bool                    readahead)
{
        struct xfs_dqblk        *dqb = bp->b_addr;
        xfs_failaddr_t          fa;
        xfs_dqid_t              id = 0;
        int                     ndquots;
        int                     i;

        /*
         * if we are in log recovery, the quota subsystem has not been
         * initialised so we have no quotainfo structure. In that case, we need
         * to manually calculate the number of dquots in the buffer.
         */
        if (mp->m_quotainfo)
                ndquots = mp->m_quotainfo->qi_dqperchunk;
        else
                ndquots = xfs_calc_dquots_per_chunk(bp->b_length);

        /*
         * On the first read of the buffer, verify that each dquot is valid.
         * We don't know what the id of the dquot is supposed to be, just that
         * they should be increasing monotonically within the buffer. If the
         * first id is corrupt, then it will fail on the second dquot in the
         * buffer so corruptions could point to the wrong dquot in this case.
         */
        for (i = 0; i < ndquots; i++) {
                struct xfs_disk_dquot   *ddq;

                ddq = &dqb[i].dd_diskdq;

                if (i == 0)
                        id = be32_to_cpu(ddq->d_id);

                fa = xfs_dqblk_verify(mp, &dqb[i], id + i);
                if (fa) {
                        if (!readahead)
                                xfs_buf_verifier_error(bp, -EFSCORRUPTED,
                                        __func__, &dqb[i],
                                        sizeof(struct xfs_dqblk), fa);
                        return fa;
                }
        }

        return NULL;
}

static xfs_failaddr_t
xfs_dquot_buf_verify_struct(
        struct xfs_buf          *bp)
{
        struct xfs_mount        *mp = bp->b_mount;

        return xfs_dquot_buf_verify(mp, bp, false);
}

static void
xfs_dquot_buf_read_verify(
        struct xfs_buf          *bp)
{
        struct xfs_mount        *mp = bp->b_mount;

        if (!xfs_dquot_buf_verify_crc(mp, bp, false))
                return;
        xfs_dquot_buf_verify(mp, bp, false);
}

/*
 * readahead errors are silent and simply leave the buffer as !done so a real
 * read will then be run with the xfs_dquot_buf_ops verifier. See
 * xfs_inode_buf_verify() for why we use EIO and ~XBF_DONE here rather than
 * reporting the failure.
 */
static void
xfs_dquot_buf_readahead_verify(
        struct xfs_buf  *bp)
{
        struct xfs_mount        *mp = bp->b_mount;

        if (!xfs_dquot_buf_verify_crc(mp, bp, true) ||
            xfs_dquot_buf_verify(mp, bp, true) != NULL) {
                xfs_buf_ioerror(bp, -EIO);
                bp->b_flags &= ~XBF_DONE;
        }
}

/*
 * we don't calculate the CRC here as that is done when the dquot is flushed to
 * the buffer after the update is done. This ensures that the dquot in the
 * buffer always has an up-to-date CRC value.
 */
static void
xfs_dquot_buf_write_verify(
        struct xfs_buf          *bp)
{
        struct xfs_mount        *mp = bp->b_mount;

        xfs_dquot_buf_verify(mp, bp, false);
}

const struct xfs_buf_ops xfs_dquot_buf_ops = {
        .name = "xfs_dquot",
        .magic16 = { cpu_to_be16(XFS_DQUOT_MAGIC),
                     cpu_to_be16(XFS_DQUOT_MAGIC) },
        .verify_read = xfs_dquot_buf_read_verify,
        .verify_write = xfs_dquot_buf_write_verify,
        .verify_struct = xfs_dquot_buf_verify_struct,
};

const struct xfs_buf_ops xfs_dquot_buf_ra_ops = {
        .name = "xfs_dquot_ra",
        .magic16 = { cpu_to_be16(XFS_DQUOT_MAGIC),
                     cpu_to_be16(XFS_DQUOT_MAGIC) },
        .verify_read = xfs_dquot_buf_readahead_verify,
        .verify_write = xfs_dquot_buf_write_verify,
};

/* Convert an on-disk timer value into an incore timer value. */
time64_t
xfs_dquot_from_disk_ts(
        struct xfs_disk_dquot   *ddq,
        __be32                  dtimer)
{
        uint32_t                t = be32_to_cpu(dtimer);

        if (t != 0 && (ddq->d_type & XFS_DQTYPE_BIGTIME))
                return xfs_dq_bigtime_to_unix(t);

        return t;
}

/* Convert an incore timer value into an on-disk timer value. */
__be32
xfs_dquot_to_disk_ts(
        struct xfs_dquot        *dqp,
        time64_t                timer)
{
        uint32_t                t = timer;

        if (timer != 0 && (dqp->q_type & XFS_DQTYPE_BIGTIME))
                t = xfs_dq_unix_to_bigtime(timer);

        return cpu_to_be32(t);
}

inline unsigned int
xfs_dqinode_sick_mask(xfs_dqtype_t type)
{
        switch (type) {
        case XFS_DQTYPE_USER:
                return XFS_SICK_FS_UQUOTA;
        case XFS_DQTYPE_GROUP:
                return XFS_SICK_FS_GQUOTA;
        case XFS_DQTYPE_PROJ:
                return XFS_SICK_FS_PQUOTA;
        }

        ASSERT(0);
        return 0;
}

/*
 * Load the inode for a given type of quota, assuming that the sb fields have
 * been sorted out.  This is not true when switching quota types on a V4
 * filesystem, so do not use this function for that.  If metadir is enabled,
 * @dp must be the /quota metadir.
 *
 * Returns -ENOENT if the quota inode field is NULLFSINO; 0 and an inode on
 * success; or a negative errno.
 */
int
xfs_dqinode_load(
        struct xfs_trans        *tp,
        struct xfs_inode        *dp,
        xfs_dqtype_t            type,
        struct xfs_inode        **ipp)
{
        struct xfs_mount        *mp = tp->t_mountp;
        struct xfs_inode        *ip;
        enum xfs_metafile_type  metafile_type = xfs_dqinode_metafile_type(type);
        int                     error;

        if (!xfs_has_metadir(mp)) {
                xfs_ino_t       ino;

                switch (type) {
                case XFS_DQTYPE_USER:
                        ino = mp->m_sb.sb_uquotino;
                        break;
                case XFS_DQTYPE_GROUP:
                        ino = mp->m_sb.sb_gquotino;
                        break;
                case XFS_DQTYPE_PROJ:
                        ino = mp->m_sb.sb_pquotino;
                        break;
                default:
                        ASSERT(0);
                        return -EFSCORRUPTED;
                }

                /* Should have set 0 to NULLFSINO when loading superblock */
                if (ino == NULLFSINO)
                        return -ENOENT;

                error = xfs_trans_metafile_iget(tp, ino, metafile_type, &ip);
        } else {
                error = xfs_metadir_load(tp, dp, xfs_dqinode_path(type),
                                metafile_type, &ip);
                if (error == -ENOENT)
                        return error;
        }
        if (error) {
                if (xfs_metadata_is_sick(error))
                        xfs_fs_mark_sick(mp, xfs_dqinode_sick_mask(type));
                return error;
        }

        if (XFS_IS_CORRUPT(mp, ip->i_df.if_format != XFS_DINODE_FMT_EXTENTS &&
                               ip->i_df.if_format != XFS_DINODE_FMT_BTREE)) {
                xfs_irele(ip);
                xfs_fs_mark_sick(mp, xfs_dqinode_sick_mask(type));
                return -EFSCORRUPTED;
        }

        if (XFS_IS_CORRUPT(mp, ip->i_projid != 0)) {
                xfs_irele(ip);
                xfs_fs_mark_sick(mp, xfs_dqinode_sick_mask(type));
                return -EFSCORRUPTED;
        }

        *ipp = ip;
        return 0;
}

/* Create a metadata directory quota inode. */
int
xfs_dqinode_metadir_create(
        struct xfs_inode                *dp,
        xfs_dqtype_t                    type,
        struct xfs_inode                **ipp)
{
        struct xfs_metadir_update       upd = {
                .dp                     = dp,
                .metafile_type          = xfs_dqinode_metafile_type(type),
                .path                   = xfs_dqinode_path(type),
        };
        int                             error;

        error = xfs_metadir_start_create(&upd);
        if (error)
                return error;

        error = xfs_metadir_create(&upd, S_IFREG);
        if (error)
                return error;

        xfs_trans_log_inode(upd.tp, upd.ip, XFS_ILOG_CORE);

        error = xfs_metadir_commit(&upd);
        if (error)
                return error;

        xfs_finish_inode_setup(upd.ip);
        *ipp = upd.ip;
        return 0;
}

#ifndef __KERNEL__
/* Link a metadata directory quota inode. */
int
xfs_dqinode_metadir_link(
        struct xfs_inode                *dp,
        xfs_dqtype_t                    type,
        struct xfs_inode                *ip)
{
        struct xfs_metadir_update       upd = {
                .dp                     = dp,
                .metafile_type          = xfs_dqinode_metafile_type(type),
                .path                   = xfs_dqinode_path(type),
                .ip                     = ip,
        };
        int                             error;

        error = xfs_metadir_start_link(&upd);
        if (error)
                return error;

        error = xfs_metadir_link(&upd);
        if (error)
                return error;

        xfs_trans_log_inode(upd.tp, upd.ip, XFS_ILOG_CORE);

        return xfs_metadir_commit(&upd);
}
#endif /* __KERNEL__ */

/* Create the parent directory for all quota inodes and load it. */
int
xfs_dqinode_mkdir_parent(
        struct xfs_mount        *mp,
        struct xfs_inode        **dpp)
{
        if (!mp->m_metadirip) {
                xfs_fs_mark_sick(mp, XFS_SICK_FS_METADIR);
                return -EFSCORRUPTED;
        }

        return xfs_metadir_mkdir(mp->m_metadirip, "quota", dpp);
}

/*
 * Load the parent directory of all quota inodes.  Pass the inode to the caller
 * because quota functions (e.g. QUOTARM) can be called on the quota files even
 * if quotas are not enabled.
 */
int
xfs_dqinode_load_parent(
        struct xfs_trans        *tp,
        struct xfs_inode        **dpp)
{
        struct xfs_mount        *mp = tp->t_mountp;

        if (!mp->m_metadirip) {
                xfs_fs_mark_sick(mp, XFS_SICK_FS_METADIR);
                return -EFSCORRUPTED;
        }

        return xfs_metadir_load(tp, mp->m_metadirip, "quota", XFS_METAFILE_DIR,
                        dpp);
}