/*      $NetBSD: dkwedge_apple.c,v 1.6 2020/04/11 16:00:34 jdolecek Exp $       */

/*-
 * Copyright (c) 2012 The NetBSD Foundation, Inc.
 * All rights reserved.
 *
 * This code is derived from software contributed to The NetBSD Foundation
 * by Christos Zoulas.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */

/*
 * Apple support for disk wedges
 */

#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: dkwedge_apple.c,v 1.6 2020/04/11 16:00:34 jdolecek Exp $");

#include <sys/param.h>
#ifdef _KERNEL
#include <sys/systm.h>
#endif
#include <sys/proc.h>
#include <sys/errno.h>
#include <sys/disk.h>
#include <sys/vnode.h>
#include <sys/bitops.h>
#include <sys/buf.h>

#include <sys/bootblock.h>

#define SWAP16(x)       ap->x = be16toh(ap->x)
#define SWAP32(x)       ap->x = be32toh(ap->x)

#ifdef DKWEDGE_DEBUG
#define DPRINTF(fmt, ...)       printf(fmt, __VA_ARGS__)
#else
#define DPRINTF(fmt, ...)       
#endif

static void
swap_apple_drvr_descriptor(struct apple_drvr_descriptor *ap)
{
        SWAP32(descBlock);
        SWAP16(descSize);
        SWAP16(descType);
}

static void
swap_apple_drvr_map(struct apple_drvr_map *ap)
{
        uint16_t i;

        SWAP16(sbSig);
        SWAP16(sbBlockSize);
        SWAP32(sbBlkCount);
        SWAP16(sbDevType);
        SWAP16(sbDevID);
        SWAP32(sbData);
        SWAP16(sbDrvrCount);

        if (ap->sbDrvrCount >= APPLE_DRVR_MAP_MAX_DESCRIPTORS)
                ap->sbDrvrCount = APPLE_DRVR_MAP_MAX_DESCRIPTORS;

        for (i = 0; i < ap->sbDrvrCount; i++)
                swap_apple_drvr_descriptor(&ap->sb_dd[i]);
}

static void
swap_apple_part_map_entry(struct apple_part_map_entry *ap)
{
        SWAP16(pmSig);
        SWAP16(pmSigPad);
        SWAP32(pmMapBlkCnt);
        SWAP32(pmPyPartStart);
        SWAP32(pmPartBlkCnt);
        SWAP32(pmLgDataStart);
        SWAP32(pmDataCnt);
        SWAP32(pmPartStatus);
        SWAP32(pmLgBootStart);
        SWAP32(pmBootSize);
        SWAP32(pmBootLoad);
        SWAP32(pmBootLoad2);
        SWAP32(pmBootEntry);
        SWAP32(pmBootEntry2);
        SWAP32(pmBootCksum);
}

static void
swap_apple_blockzeroblock(struct apple_blockzeroblock *ap)
{
        SWAP32(bzbMagic);
        SWAP16(bzbBadBlockInode);
        SWAP16(bzbFlags);
        SWAP16(bzbReserved);
        SWAP32(bzbCreationTime);
        SWAP32(bzbMountTime);
        SWAP32(bzbUMountTime);
}

#undef SWAP16
#undef SWAP32

#define ASIZE   16384
 
static struct {
        const char *name;
        const char *type;
} map[] = {
        { APPLE_PART_TYPE_UNIX, DKW_PTYPE_SYSV },
        { APPLE_PART_TYPE_MAC, DKW_PTYPE_APPLEHFS },
};


static int
dkwedge_discover_apple(struct disk *pdk, struct vnode *vp)
{
        size_t i, n;
        int error;
        struct buf *bp;
        uint32_t blocksize, blockcount, offset, rsize;
        struct apple_drvr_map *am;
        struct apple_part_map_entry *ae;
        struct apple_blockzeroblock ab;
        const char *ptype;

        bp = geteblk(ASIZE);
        if ((error = dkwedge_read(pdk, vp, 0, bp->b_data, ASIZE)) != 0) {
                DPRINTF("%s: read @%u %d\n", __func__, 0, error);
                goto out;
        }

        am = bp->b_data;
        swap_apple_drvr_map(am);

        error = ESRCH;

        if (am->sbSig != APPLE_DRVR_MAP_MAGIC) {
                DPRINTF("%s: drvr magic %x != %x\n", __func__, am->sbSig,
                    APPLE_DRVR_MAP_MAGIC);
                goto out;
        }

        blocksize = am->sbBlockSize;

        rsize = 1 << (ilog2(MAX(sizeof(*ae), blocksize) - 1) + 1);
        if (ASIZE < rsize) {
                DPRINTF("%s: buffer too small %u < %u\n", __func__, ASIZE,
                    rsize);
                goto out;
        }

        /* XXX Clamp entries at 512 for now. */
        blockcount = am->sbBlkCount;
        if (blockcount > 512) {
                aprint_error("%s: WARNING: clamping number of blocks to "
                    "512 (was %u)\n", pdk->dk_name, blockcount);
                blockcount = 512;
        }

        ae = bp->b_data;
        offset = blocksize;
        for (n = 0; n < blockcount; n++, offset += rsize) {
                DPRINTF("%s: offset %x rsize %x\n", __func__, offset, rsize);
                if ((error = dkwedge_read(pdk, vp, offset / DEV_BSIZE,
                    bp->b_data, rsize)) != 0) {
                        DPRINTF("%s: read @%u %d\n", __func__, offset,
                            error);
                        goto out;
                }
                
                swap_apple_part_map_entry(ae);
                if (ae->pmSig != APPLE_PART_MAP_ENTRY_MAGIC) {
                        DPRINTF("%s: part magic %x != %x\n", __func__,
                            ae->pmSig, APPLE_PART_MAP_ENTRY_MAGIC);
                        break;
                }

                for (i = 0; i < __arraycount(map); i++)
                        if (strcasecmp(map[i].name, ae->pmPartType) == 0)
                                break;

                DPRINTF("%s: %s/%s PH=%u/%u LG=%u/%u\n", __func__,
                    ae->pmPartName, ae->pmPartType,
                    ae->pmPyPartStart, ae->pmPartBlkCnt,
                    ae->pmLgDataStart, ae->pmDataCnt);

                if (i == __arraycount(map))
                        continue;

                ptype = map[i].type;
                memcpy(&ab, ae->pmBootArgs, sizeof(ab));
                swap_apple_blockzeroblock(&ab);
                if (ab.bzbMagic == APPLE_BZB_MAGIC) {
                        if (ab.bzbType == APPLE_BZB_TYPESWAP)
                                ptype = DKW_PTYPE_SWAP;
                }

                struct dkwedge_info dkw;
                memset(&dkw, 0, sizeof(dkw));

                strlcpy(dkw.dkw_ptype, ptype, sizeof(dkw.dkw_ptype));
                strlcpy(dkw.dkw_parent, pdk->dk_name, sizeof(dkw.dkw_parent));
                dkw.dkw_offset = ae->pmPyPartStart;
                dkw.dkw_size = ae->pmPartBlkCnt;
                strlcpy(dkw.dkw_wname, ae->pmPartName, sizeof(dkw.dkw_wname));
                error = dkwedge_add(&dkw);
                if (error == EEXIST)
                        aprint_error("%s: wedge named '%s' already "
                            "exists, manual intervention required\n",
                            pdk->dk_name, dkw.dkw_wname);
                else if (error)
                        aprint_error("%s: error %d adding partition "
                            "%s type %s\n", pdk->dk_name, error,
                            ae->pmPartType, dkw.dkw_ptype);
        }

out:
        brelse(bp, 0);
        DPRINTF("%s: return %d\n", __func__, error);
        return error;
}

#ifdef _KERNEL
DKWEDGE_DISCOVERY_METHOD_DECL(APPLE, -5, dkwedge_discover_apple);
#endif