// SPDX-License-Identifier: GPL-2.0
/*
 * Copyright (c) 2000-2002,2005 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_inode.h"
#include "xfs_btree.h"
#include "xfs_ialloc.h"
#include "xfs_ialloc_btree.h"
#include "xfs_iwalk.h"
#include "xfs_itable.h"
#include "xfs_error.h"
#include "xfs_icache.h"
#include "xfs_health.h"
#include "xfs_trans.h"

/*
 * Bulk Stat
 * =========
 *
 * Use the inode walking functions to fill out struct xfs_bulkstat for every
 * allocated inode, then pass the stat information to some externally provided
 * iteration function.
 */

struct xfs_bstat_chunk {
        bulkstat_one_fmt_pf     formatter;
        struct xfs_ibulk        *breq;
        struct xfs_bulkstat     *buf;
};

static inline bool
want_metadir_file(
        struct xfs_inode        *ip,
        struct xfs_ibulk        *breq)
{
        return xfs_is_metadir_inode(ip) && (breq->flags & XFS_IBULK_METADIR);
}

/*
 * Fill out the bulkstat info for a single inode and report it somewhere.
 *
 * bc->breq->lastino is effectively the inode cursor as we walk through the
 * filesystem.  Therefore, we update it any time we need to move the cursor
 * forward, regardless of whether or not we're sending any bstat information
 * back to userspace.  If the inode is internal metadata or, has been freed
 * out from under us, we just simply keep going.
 *
 * However, if any other type of error happens we want to stop right where we
 * are so that userspace will call back with exact number of the bad inode and
 * we can send back an error code.
 *
 * Note that if the formatter tells us there's no space left in the buffer we
 * move the cursor forward and abort the walk.
 */
STATIC int
xfs_bulkstat_one_int(
        struct xfs_mount        *mp,
        struct mnt_idmap        *idmap,
        struct xfs_trans        *tp,
        xfs_ino_t               ino,
        struct xfs_bstat_chunk  *bc)
{
        struct user_namespace   *sb_userns = mp->m_super->s_user_ns;
        struct xfs_inode        *ip;            /* incore inode pointer */
        struct inode            *inode;
        struct xfs_bulkstat     *buf = bc->buf;
        xfs_extnum_t            nextents;
        int                     error = -EINVAL;
        vfsuid_t                vfsuid;
        vfsgid_t                vfsgid;

        error = xfs_iget(mp, tp, ino,
                         (XFS_IGET_DONTCACHE | XFS_IGET_UNTRUSTED),
                         XFS_ILOCK_SHARED, &ip);
        if (error == -ENOENT || error == -EINVAL)
                goto out_advance;
        if (error)
                goto out;

        /* Reload the incore unlinked list to avoid failure in inodegc. */
        if (xfs_inode_unlinked_incomplete(ip)) {
                error = xfs_inode_reload_unlinked_bucket(tp, ip);
                if (error) {
                        xfs_iunlock(ip, XFS_ILOCK_SHARED);
                        xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE);
                        xfs_irele(ip);
                        return error;
                }
        }

        ASSERT(ip != NULL);
        ASSERT(ip->i_imap.im_blkno != 0);
        inode = VFS_I(ip);
        vfsuid = i_uid_into_vfsuid(idmap, inode);
        vfsgid = i_gid_into_vfsgid(idmap, inode);

        /*
         * If caller wants files from the metadata directories, push out the
         * bare minimum information for enabling scrub.
         */
        if (want_metadir_file(ip, bc->breq)) {
                memset(buf, 0, sizeof(*buf));
                buf->bs_ino = ino;
                buf->bs_gen = inode->i_generation;
                buf->bs_mode = inode->i_mode & S_IFMT;
                xfs_bulkstat_health(ip, buf);
                buf->bs_version = XFS_BULKSTAT_VERSION_V5;
                xfs_iunlock(ip, XFS_ILOCK_SHARED);
                xfs_irele(ip);

                error = bc->formatter(bc->breq, buf);
                if (!error || error == -ECANCELED)
                        goto out_advance;
                goto out;
        }

        /* If this is a private inode, don't leak its details to userspace. */
        if (IS_PRIVATE(inode) || xfs_is_sb_inum(mp, ino)) {
                xfs_iunlock(ip, XFS_ILOCK_SHARED);
                xfs_irele(ip);
                error = -EINVAL;
                goto out_advance;
        }

        /* xfs_iget returns the following without needing
         * further change.
         */
        buf->bs_projectid = ip->i_projid;
        buf->bs_ino = ino;
        buf->bs_uid = from_kuid(sb_userns, vfsuid_into_kuid(vfsuid));
        buf->bs_gid = from_kgid(sb_userns, vfsgid_into_kgid(vfsgid));
        buf->bs_size = ip->i_disk_size;

        buf->bs_nlink = inode->i_nlink;
        buf->bs_atime = inode_get_atime_sec(inode);
        buf->bs_atime_nsec = inode_get_atime_nsec(inode);
        buf->bs_mtime = inode_get_mtime_sec(inode);
        buf->bs_mtime_nsec = inode_get_mtime_nsec(inode);
        buf->bs_ctime = inode_get_ctime_sec(inode);
        buf->bs_ctime_nsec = inode_get_ctime_nsec(inode);
        buf->bs_gen = inode->i_generation;
        buf->bs_mode = inode->i_mode;

        buf->bs_xflags = xfs_ip2xflags(ip);
        buf->bs_extsize_blks = ip->i_extsize;

        nextents = xfs_ifork_nextents(&ip->i_df);
        if (!(bc->breq->flags & XFS_IBULK_NREXT64))
                buf->bs_extents = min(nextents, XFS_MAX_EXTCNT_DATA_FORK_SMALL);
        else
                buf->bs_extents64 = nextents;

        xfs_bulkstat_health(ip, buf);
        buf->bs_aextents = xfs_ifork_nextents(&ip->i_af);
        buf->bs_forkoff = xfs_inode_fork_boff(ip);
        buf->bs_version = XFS_BULKSTAT_VERSION_V5;

        if (xfs_has_v3inodes(mp)) {
                buf->bs_btime = ip->i_crtime.tv_sec;
                buf->bs_btime_nsec = ip->i_crtime.tv_nsec;
                if (ip->i_diflags2 & XFS_DIFLAG2_COWEXTSIZE)
                        buf->bs_cowextsize_blks = ip->i_cowextsize;
        }

        switch (ip->i_df.if_format) {
        case XFS_DINODE_FMT_DEV:
                buf->bs_rdev = sysv_encode_dev(inode->i_rdev);
                buf->bs_blksize = BLKDEV_IOSIZE;
                buf->bs_blocks = 0;
                break;
        case XFS_DINODE_FMT_LOCAL:
                buf->bs_rdev = 0;
                buf->bs_blksize = mp->m_sb.sb_blocksize;
                buf->bs_blocks = 0;
                break;
        case XFS_DINODE_FMT_EXTENTS:
        case XFS_DINODE_FMT_BTREE:
                buf->bs_rdev = 0;
                buf->bs_blksize = mp->m_sb.sb_blocksize;
                buf->bs_blocks = ip->i_nblocks + ip->i_delayed_blks;
                break;
        }
        xfs_iunlock(ip, XFS_ILOCK_SHARED);
        xfs_irele(ip);

        error = bc->formatter(bc->breq, buf);
        if (error == -ECANCELED)
                goto out_advance;
        if (error)
                goto out;

out_advance:
        /*
         * Advance the cursor to the inode that comes after the one we just
         * looked at.  We want the caller to move along if the bulkstat
         * information was copied successfully; if we tried to grab the inode
         * but it's no longer allocated; or if it's internal metadata.
         */
        bc->breq->startino = ino + 1;
out:
        return error;
}

/* Bulkstat a single inode. */
int
xfs_bulkstat_one(
        struct xfs_ibulk        *breq,
        bulkstat_one_fmt_pf     formatter)
{
        struct xfs_bstat_chunk  bc = {
                .formatter      = formatter,
                .breq           = breq,
        };
        struct xfs_trans        *tp;
        int                     error;

        if (breq->idmap != &nop_mnt_idmap) {
                xfs_warn_ratelimited(breq->mp,
                        "bulkstat not supported inside of idmapped mounts.");
                return -EINVAL;
        }

        ASSERT(breq->icount == 1);

        bc.buf = kzalloc_obj(struct xfs_bulkstat,
                             GFP_KERNEL | __GFP_RETRY_MAYFAIL);
        if (!bc.buf)
                return -ENOMEM;

        /*
         * Grab an empty transaction so that we can use its recursive buffer
         * locking abilities to detect cycles in the inobt without deadlocking.
         */
        tp = xfs_trans_alloc_empty(breq->mp);
        error = xfs_bulkstat_one_int(breq->mp, breq->idmap, tp,
                        breq->startino, &bc);
        xfs_trans_cancel(tp);
        kfree(bc.buf);

        /*
         * If we reported one inode to userspace then we abort because we hit
         * the end of the buffer.  Don't leak that back to userspace.
         */
        if (error == -ECANCELED)
                error = 0;

        return error;
}

static int
xfs_bulkstat_iwalk(
        struct xfs_mount        *mp,
        struct xfs_trans        *tp,
        xfs_ino_t               ino,
        void                    *data)
{
        struct xfs_bstat_chunk  *bc = data;
        int                     error;

        error = xfs_bulkstat_one_int(mp, bc->breq->idmap, tp, ino, data);
        /* bulkstat just skips over missing inodes */
        if (error == -ENOENT || error == -EINVAL)
                return 0;
        return error;
}

/*
 * Check the incoming lastino parameter.
 *
 * We allow any inode value that could map to physical space inside the
 * filesystem because if there are no inodes there, bulkstat moves on to the
 * next chunk.  In other words, the magic agino value of zero takes us to the
 * first chunk in the AG, and an agino value past the end of the AG takes us to
 * the first chunk in the next AG.
 *
 * Therefore we can end early if the requested inode is beyond the end of the
 * filesystem or doesn't map properly.
 */
static inline bool
xfs_bulkstat_already_done(
        struct xfs_mount        *mp,
        xfs_ino_t               startino)
{
        xfs_agnumber_t          agno = XFS_INO_TO_AGNO(mp, startino);
        xfs_agino_t             agino = XFS_INO_TO_AGINO(mp, startino);

        return agno >= mp->m_sb.sb_agcount ||
               startino != XFS_AGINO_TO_INO(mp, agno, agino);
}

/* Return stat information in bulk (by-inode) for the filesystem. */
int
xfs_bulkstat(
        struct xfs_ibulk        *breq,
        bulkstat_one_fmt_pf     formatter)
{
        struct xfs_bstat_chunk  bc = {
                .formatter      = formatter,
                .breq           = breq,
        };
        struct xfs_trans        *tp;
        int                     error;

        if (breq->idmap != &nop_mnt_idmap) {
                xfs_warn_ratelimited(breq->mp,
                        "bulkstat not supported inside of idmapped mounts.");
                return -EINVAL;
        }
        if (xfs_bulkstat_already_done(breq->mp, breq->startino))
                return 0;

        bc.buf = kzalloc_obj(struct xfs_bulkstat,
                             GFP_KERNEL | __GFP_RETRY_MAYFAIL);
        if (!bc.buf)
                return -ENOMEM;

        /*
         * Grab an empty transaction so that we can use its recursive buffer
         * locking abilities to detect cycles in the inobt without deadlocking.
         */
        tp = xfs_trans_alloc_empty(breq->mp);
        error = xfs_iwalk(breq->mp, tp, breq->startino, breq->iwalk_flags,
                        xfs_bulkstat_iwalk, breq->icount, &bc);
        xfs_trans_cancel(tp);
        kfree(bc.buf);

        /*
         * We found some inodes, so clear the error status and return them.
         * The lastino pointer will point directly at the inode that triggered
         * any error that occurred, so on the next call the error will be
         * triggered again and propagated to userspace as there will be no
         * formatted inodes in the buffer.
         */
        if (breq->ocount > 0)
                error = 0;

        return error;
}

/* Convert bulkstat (v5) to bstat (v1). */
void
xfs_bulkstat_to_bstat(
        struct xfs_mount                *mp,
        struct xfs_bstat                *bs1,
        const struct xfs_bulkstat       *bstat)
{
        /* memset is needed here because of padding holes in the structure. */
        memset(bs1, 0, sizeof(struct xfs_bstat));
        bs1->bs_ino = bstat->bs_ino;
        bs1->bs_mode = bstat->bs_mode;
        bs1->bs_nlink = bstat->bs_nlink;
        bs1->bs_uid = bstat->bs_uid;
        bs1->bs_gid = bstat->bs_gid;
        bs1->bs_rdev = bstat->bs_rdev;
        bs1->bs_blksize = bstat->bs_blksize;
        bs1->bs_size = bstat->bs_size;
        bs1->bs_atime.tv_sec = bstat->bs_atime;
        bs1->bs_mtime.tv_sec = bstat->bs_mtime;
        bs1->bs_ctime.tv_sec = bstat->bs_ctime;
        bs1->bs_atime.tv_nsec = bstat->bs_atime_nsec;
        bs1->bs_mtime.tv_nsec = bstat->bs_mtime_nsec;
        bs1->bs_ctime.tv_nsec = bstat->bs_ctime_nsec;
        bs1->bs_blocks = bstat->bs_blocks;
        bs1->bs_xflags = bstat->bs_xflags;
        bs1->bs_extsize = XFS_FSB_TO_B(mp, bstat->bs_extsize_blks);
        bs1->bs_extents = bstat->bs_extents;
        bs1->bs_gen = bstat->bs_gen;
        bs1->bs_projid_lo = bstat->bs_projectid & 0xFFFF;
        bs1->bs_forkoff = bstat->bs_forkoff;
        bs1->bs_projid_hi = bstat->bs_projectid >> 16;
        bs1->bs_sick = bstat->bs_sick;
        bs1->bs_checked = bstat->bs_checked;
        bs1->bs_cowextsize = XFS_FSB_TO_B(mp, bstat->bs_cowextsize_blks);
        bs1->bs_dmevmask = 0;
        bs1->bs_dmstate = 0;
        bs1->bs_aextents = bstat->bs_aextents;
}

struct xfs_inumbers_chunk {
        inumbers_fmt_pf         formatter;
        struct xfs_ibulk        *breq;
};

/*
 * INUMBERS
 * ========
 * This is how we export inode btree records to userspace, so that XFS tools
 * can figure out where inodes are allocated.
 */

/*
 * Format the inode group structure and report it somewhere.
 *
 * Similar to xfs_bulkstat_one_int, lastino is the inode cursor as we walk
 * through the filesystem so we move it forward unless there was a runtime
 * error.  If the formatter tells us the buffer is now full we also move the
 * cursor forward and abort the walk.
 */
STATIC int
xfs_inumbers_walk(
        struct xfs_mount        *mp,
        struct xfs_trans        *tp,
        xfs_agnumber_t          agno,
        const struct xfs_inobt_rec_incore *irec,
        void                    *data)
{
        struct xfs_inumbers     inogrp = {
                .xi_startino    = XFS_AGINO_TO_INO(mp, agno, irec->ir_startino),
                .xi_alloccount  = irec->ir_count - irec->ir_freecount,
                .xi_allocmask   = ~irec->ir_free,
                .xi_version     = XFS_INUMBERS_VERSION_V5,
        };
        struct xfs_inumbers_chunk *ic = data;
        int                     error;

        error = ic->formatter(ic->breq, &inogrp);
        if (error && error != -ECANCELED)
                return error;

        ic->breq->startino = XFS_AGINO_TO_INO(mp, agno, irec->ir_startino) +
                        XFS_INODES_PER_CHUNK;
        return error;
}

/*
 * Return inode number table for the filesystem.
 */
int
xfs_inumbers(
        struct xfs_ibulk        *breq,
        inumbers_fmt_pf         formatter)
{
        struct xfs_inumbers_chunk ic = {
                .formatter      = formatter,
                .breq           = breq,
        };
        struct xfs_trans        *tp;
        int                     error = 0;

        if (xfs_bulkstat_already_done(breq->mp, breq->startino))
                return 0;

        /*
         * Grab an empty transaction so that we can use its recursive buffer
         * locking abilities to detect cycles in the inobt without deadlocking.
         */
        tp = xfs_trans_alloc_empty(breq->mp);
        error = xfs_inobt_walk(breq->mp, tp, breq->startino, breq->iwalk_flags,
                        xfs_inumbers_walk, breq->icount, &ic);
        xfs_trans_cancel(tp);

        /*
         * We found some inode groups, so clear the error status and return
         * them.  The lastino pointer will point directly at the inode that
         * triggered any error that occurred, so on the next call the error
         * will be triggered again and propagated to userspace as there will be
         * no formatted inode groups in the buffer.
         */
        if (breq->ocount > 0)
                error = 0;

        return error;
}

/* Convert an inumbers (v5) struct to a inogrp (v1) struct. */
void
xfs_inumbers_to_inogrp(
        struct xfs_inogrp               *ig1,
        const struct xfs_inumbers       *ig)
{
        /* memset is needed here because of padding holes in the structure. */
        memset(ig1, 0, sizeof(struct xfs_inogrp));
        ig1->xi_startino = ig->xi_startino;
        ig1->xi_alloccount = ig->xi_alloccount;
        ig1->xi_allocmask = ig->xi_allocmask;
}