/*
* QEMU S390 bootmap interpreter
*
* Copyright (c) 2009 Alexander Graf <agraf@suse.de>
*
* This work is licensed under the terms of the GNU GPL, version 2 or (at
* your option) any later version. See the COPYING file in the top-level
* directory.
*/
#include "s390-ccw.h"
#include "bootmap.h"
#include "virtio.h"
#ifdef DEBUG
/* #define DEBUG_FALLBACK */
#endif
#ifdef DEBUG_FALLBACK
#define dputs(txt) \
do { sclp_print("zipl: " txt); } while (0)
#else
#define dputs(fmt, ...) \
do { } while (0)
#endif
/* Scratch space */
static uint8_t sec[MAX_SECTOR_SIZE*4] __attribute__((__aligned__(PAGE_SIZE)));
typedef struct ResetInfo {
uint32_t ipl_mask;
uint32_t ipl_addr;
uint32_t ipl_continue;
} ResetInfo;
static ResetInfo save;
static void jump_to_IPL_2(void)
{
ResetInfo *current = 0;
void (*ipl)(void) = (void *) (uint64_t) current->ipl_continue;
*current = save;
ipl(); /* should not return */
}
static void jump_to_IPL_code(uint64_t address)
{
/* store the subsystem information _after_ the bootmap was loaded */
write_subsystem_identification();
/*
* The IPL PSW is at address 0. We also must not overwrite the
* content of non-BIOS memory after we loaded the guest, so we
* save the original content and restore it in jump_to_IPL_2.
*/
ResetInfo *current = 0;
save = *current;
current->ipl_addr = (uint32_t) (uint64_t) &jump_to_IPL_2;
current->ipl_continue = address & 0x7fffffff;
debug_print_int("set IPL addr to", current->ipl_continue);
/* Ensure the guest output starts fresh */
sclp_print("\n");
/*
* HACK ALERT.
* We use the load normal reset to keep r15 unchanged. jump_to_IPL_2
* can then use r15 as its stack pointer.
*/
asm volatile("lghi 1,1\n\t"
"diag 1,1,0x308\n\t"
: : : "1", "memory");
panic("\n! IPL returns !\n");
}
/***********************************************************************
* IPL an ECKD DASD (CDL or LDL/CMS format)
*/
static unsigned char _bprs[8*1024]; /* guessed "max" ECKD sector size */
static const int max_bprs_entries = sizeof(_bprs) / sizeof(ExtEckdBlockPtr);
static inline void verify_boot_info(BootInfo *bip)
{
IPL_assert(magic_match(bip->magic, ZIPL_MAGIC), "No zIPL sig in BootInfo");
IPL_assert(bip->version == BOOT_INFO_VERSION, "Wrong zIPL version");
IPL_assert(bip->bp_type == BOOT_INFO_BP_TYPE_IPL, "DASD is not for IPL");
IPL_assert(bip->dev_type == BOOT_INFO_DEV_TYPE_ECKD, "DASD is not ECKD");
IPL_assert(bip->flags == BOOT_INFO_FLAGS_ARCH, "Not for this arch");
IPL_assert(block_size_ok(bip->bp.ipl.bm_ptr.eckd.bptr.size),
"Bad block size in zIPL section of the 1st record.");
}
static block_number_t eckd_block_num(BootMapPointer *p)
{
const uint64_t sectors = virtio_get_sectors();
const uint64_t heads = virtio_get_heads();
const uint64_t cylinder = p->eckd.cylinder
+ ((p->eckd.head & 0xfff0) << 12);
const uint64_t head = p->eckd.head & 0x000f;
const block_number_t block = sectors * heads * cylinder
+ sectors * head
+ p->eckd.sector
- 1; /* block nr starts with zero */
return block;
}
static bool eckd_valid_address(BootMapPointer *p)
{
const uint64_t head = p->eckd.head & 0x000f;
if (head >= virtio_get_heads()
|| p->eckd.sector > virtio_get_sectors()
|| p->eckd.sector <= 0) {
return false;
}
if (!virtio_guessed_disk_nature() &&
eckd_block_num(p) >= virtio_get_blocks()) {
return false;
}
return true;
}
static block_number_t load_eckd_segments(block_number_t blk, uint64_t *address)
{
block_number_t block_nr;
int j, rc;
BootMapPointer *bprs = (void *)_bprs;
bool more_data;
memset(_bprs, FREE_SPACE_FILLER, sizeof(_bprs));
read_block(blk, bprs, "BPRS read failed");
do {
more_data = false;
for (j = 0;; j++) {
block_nr = eckd_block_num((void *)&(bprs[j].xeckd));
if (is_null_block_number(block_nr)) { /* end of chunk */
break;
}
/* we need the updated blockno for the next indirect entry
* in the chain, but don't want to advance address
*/
if (j == (max_bprs_entries - 1)) {
break;
}
IPL_assert(block_size_ok(bprs[j].xeckd.bptr.size),
"bad chunk block size");
IPL_assert(eckd_valid_address(&bprs[j]), "bad chunk ECKD addr");
if ((bprs[j].xeckd.bptr.count == 0) && unused_space(&(bprs[j+1]),
sizeof(EckdBlockPtr))) {
/* This is a "continue" pointer.
* This ptr should be the last one in the current
* script section.
* I.e. the next ptr must point to the unused memory area
*/
memset(_bprs, FREE_SPACE_FILLER, sizeof(_bprs));
read_block(block_nr, bprs, "BPRS continuation read failed");
more_data = true;
break;
}
/* Load (count+1) blocks of code at (block_nr)
* to memory (address).
*/
rc = virtio_read_many(block_nr, (void *)(*address),
bprs[j].xeckd.bptr.count+1);
IPL_assert(rc == 0, "code chunk read failed");
*address += (bprs[j].xeckd.bptr.count+1) * virtio_get_block_size();
}
} while (more_data);
return block_nr;
}
static void run_eckd_boot_script(block_number_t mbr_block_nr)
{
int i;
block_number_t block_nr;
uint64_t address;
ScsiMbr *scsi_mbr = (void *)sec;
BootMapScript *bms = (void *)sec;
memset(sec, FREE_SPACE_FILLER, sizeof(sec));
read_block(mbr_block_nr, sec, "Cannot read MBR");
block_nr = eckd_block_num((void *)&(scsi_mbr->blockptr));
memset(sec, FREE_SPACE_FILLER, sizeof(sec));
read_block(block_nr, sec, "Cannot read Boot Map Script");
for (i = 0; bms->entry[i].type == BOOT_SCRIPT_LOAD; i++) {
address = bms->entry[i].address.load_address;
block_nr = eckd_block_num(&(bms->entry[i].blkptr));
do {
block_nr = load_eckd_segments(block_nr, &address);
} while (block_nr != -1);
}
IPL_assert(bms->entry[i].type == BOOT_SCRIPT_EXEC,
"Unknown script entry type");
jump_to_IPL_code(bms->entry[i].address.load_address); /* no return */
}
static void ipl_eckd_cdl(void)
{
XEckdMbr *mbr;
Ipl2 *ipl2 = (void *)sec;
IplVolumeLabel *vlbl = (void *)sec;
block_number_t block_nr;
/* we have just read the block #0 and recognized it as "IPL1" */
sclp_print("CDL\n");
memset(sec, FREE_SPACE_FILLER, sizeof(sec));
read_block(1, ipl2, "Cannot read IPL2 record at block 1");
mbr = &ipl2->u.x.mbr;
IPL_assert(magic_match(mbr, ZIPL_MAGIC), "No zIPL section in IPL2 record.");
IPL_assert(block_size_ok(mbr->blockptr.xeckd.bptr.size),
"Bad block size in zIPL section of IPL2 record.");
IPL_assert(mbr->dev_type == DEV_TYPE_ECKD,
"Non-ECKD device type in zIPL section of IPL2 record.");
/* save pointer to Boot Script */
block_nr = eckd_block_num((void *)&(mbr->blockptr));
memset(sec, FREE_SPACE_FILLER, sizeof(sec));
read_block(2, vlbl, "Cannot read Volume Label at block 2");
IPL_assert(magic_match(vlbl->key, VOL1_MAGIC),
"Invalid magic of volume label block");
IPL_assert(magic_match(vlbl->f.key, VOL1_MAGIC),
"Invalid magic of volser block");
print_volser(vlbl->f.volser);
run_eckd_boot_script(block_nr);
/* no return */
}
static void print_eckd_ldl_msg(ECKD_IPL_mode_t mode)
{
LDL_VTOC *vlbl = (void *)sec; /* already read, 3rd block */
char msg[4] = { '?', '.', '\n', '\0' };
sclp_print((mode == ECKD_CMS) ? "CMS" : "LDL");
sclp_print(" version ");
switch (vlbl->LDL_version) {
case LDL1_VERSION:
msg[0] = '1';
break;
case LDL2_VERSION:
msg[0] = '2';
break;
default:
msg[0] = vlbl->LDL_version;
msg[0] &= 0x0f; /* convert EBCDIC */
msg[0] |= 0x30; /* to ASCII (digit) */
msg[1] = '?';
break;
}
sclp_print(msg);
print_volser(vlbl->volser);
}
static void ipl_eckd_ldl(ECKD_IPL_mode_t mode)
{
block_number_t block_nr;
BootInfo *bip = (void *)(sec + 0x70); /* BootInfo is MBR for LDL */
if (mode != ECKD_LDL_UNLABELED) {
print_eckd_ldl_msg(mode);
}
/* DO NOT read BootMap pointer (only one, xECKD) at block #2 */
memset(sec, FREE_SPACE_FILLER, sizeof(sec));
read_block(0, sec, "Cannot read block 0 to grab boot info.");
if (mode == ECKD_LDL_UNLABELED) {
if (!magic_match(bip->magic, ZIPL_MAGIC)) {
return; /* not applicable layout */
}
sclp_print("unlabeled LDL.\n");
}
verify_boot_info(bip);
block_nr = eckd_block_num((void *)&(bip->bp.ipl.bm_ptr.eckd.bptr));
run_eckd_boot_script(block_nr);
/* no return */
}
static void print_eckd_msg(void)
{
char msg[] = "Using ECKD scheme (block size *****), ";
char *p = &msg[34], *q = &msg[30];
int n = virtio_get_block_size();
/* Fill in the block size and show up the message */
if (n > 0 && n <= 99999) {
while (n) {
*p-- = '0' + (n % 10);
n /= 10;
}
while (p >= q) {
*p-- = ' ';
}
}
sclp_print(msg);
}
static void ipl_eckd(void)
{
ScsiMbr *mbr = (void *)sec;
LDL_VTOC *vlbl = (void *)sec;
print_eckd_msg();
/* Grab the MBR again */
memset(sec, FREE_SPACE_FILLER, sizeof(sec));
read_block(0, mbr, "Cannot read block 0 on DASD");
if (magic_match(mbr->magic, IPL1_MAGIC)) {
ipl_eckd_cdl(); /* no return */
}
/* LDL/CMS? */
memset(sec, FREE_SPACE_FILLER, sizeof(sec));
read_block(2, vlbl, "Cannot read block 2");
if (magic_match(vlbl->magic, CMS1_MAGIC)) {
ipl_eckd_ldl(ECKD_CMS); /* no return */
}
if (magic_match(vlbl->magic, LNX1_MAGIC)) {
ipl_eckd_ldl(ECKD_LDL); /* no return */
}
ipl_eckd_ldl(ECKD_LDL_UNLABELED); /* it still may return */
/*
* Ok, it is not a LDL by any means.
* It still might be a CDL with zero record keys for IPL1 and IPL2
*/
ipl_eckd_cdl();
}
/***********************************************************************
* IPL a SCSI disk
*/
static void zipl_load_segment(ComponentEntry *entry)
{
const int max_entries = (MAX_SECTOR_SIZE / sizeof(ScsiBlockPtr));
ScsiBlockPtr *bprs = (void *)sec;
const int bprs_size = sizeof(sec);
block_number_t blockno;
uint64_t address;
int i;
char err_msg[] = "zIPL failed to read BPRS at 0xZZZZZZZZZZZZZZZZ";
char *blk_no = &err_msg[30]; /* where to print blockno in (those ZZs) */
blockno = entry->data.blockno;
address = entry->load_address;
debug_print_int("loading segment at block", blockno);
debug_print_int("addr", address);
do {
memset(bprs, FREE_SPACE_FILLER, bprs_size);
fill_hex_val(blk_no, &blockno, sizeof(blockno));
read_block(blockno, bprs, err_msg);
for (i = 0;; i++) {
uint64_t *cur_desc = (void *)&bprs[i];
blockno = bprs[i].blockno;
if (!blockno) {
break;
}
/* we need the updated blockno for the next indirect entry in the
chain, but don't want to advance address */
if (i == (max_entries - 1)) {
break;
}
if (bprs[i].blockct == 0 && unused_space(&bprs[i + 1],
sizeof(ScsiBlockPtr))) {
/* This is a "continue" pointer.
* This ptr is the last one in the current script section.
* I.e. the next ptr must point to the unused memory area.
* The blockno is not zero, so the upper loop must continue
* reading next section of BPRS.
*/
break;
}
address = virtio_load_direct(cur_desc[0], cur_desc[1], 0,
(void *)address);
IPL_assert(address != -1, "zIPL load segment failed");
}
} while (blockno);
}
/* Run a zipl program */
static void zipl_run(ScsiBlockPtr *pte)
{
ComponentHeader *header;
ComponentEntry *entry;
uint8_t tmp_sec[MAX_SECTOR_SIZE];
read_block(pte->blockno, tmp_sec, "Cannot read header");
header = (ComponentHeader *)tmp_sec;
IPL_assert(magic_match(tmp_sec, ZIPL_MAGIC), "No zIPL magic in header");
IPL_assert(header->type == ZIPL_COMP_HEADER_IPL, "Bad header type");
dputs("start loading images\n");
/* Load image(s) into RAM */
entry = (ComponentEntry *)(&header[1]);
while (entry->component_type == ZIPL_COMP_ENTRY_LOAD) {
zipl_load_segment(entry);
entry++;
IPL_assert((uint8_t *)(&entry[1]) <= (tmp_sec + MAX_SECTOR_SIZE),
"Wrong entry value");
}
IPL_assert(entry->component_type == ZIPL_COMP_ENTRY_EXEC, "No EXEC entry");
/* should not return */
jump_to_IPL_code(entry->load_address);
}
static void ipl_scsi(void)
{
ScsiMbr *mbr = (void *)sec;
uint8_t *ns, *ns_end;
int program_table_entries = 0;
const int pte_len = sizeof(ScsiBlockPtr);
ScsiBlockPtr *prog_table_entry = NULL;
unsigned int loadparm = get_loadparm_index();
/* Grab the MBR */
memset(sec, FREE_SPACE_FILLER, sizeof(sec));
read_block(0, mbr, "Cannot read block 0");
if (!magic_match(mbr->magic, ZIPL_MAGIC)) {
return;
}
sclp_print("Using SCSI scheme.\n");
debug_print_int("MBR Version", mbr->version_id);
IPL_check(mbr->version_id == 1,
"Unknown MBR layout version, assuming version 1");
debug_print_int("program table", mbr->blockptr.blockno);
IPL_assert(mbr->blockptr.blockno, "No Program Table");
/* Parse the program table */
read_block(mbr->blockptr.blockno, sec,
"Error reading Program Table");
IPL_assert(magic_match(sec, ZIPL_MAGIC), "No zIPL magic in PT");
debug_print_int("loadparm index", loadparm);
ns_end = sec + virtio_get_block_size();
for (ns = (sec + pte_len); (ns + pte_len) < ns_end; ns += pte_len) {
prog_table_entry = (ScsiBlockPtr *)ns;
if (!prog_table_entry->blockno) {
break;
}
program_table_entries++;
if (program_table_entries == loadparm + 1) {
break; /* selected entry found */
}
}
debug_print_int("program table entries", program_table_entries);
IPL_assert(program_table_entries != 0, "Empty Program Table");
zipl_run(prog_table_entry); /* no return */
}
/***********************************************************************
* IPL El Torito ISO9660 image or DVD
*/
static bool is_iso_bc_entry_compatible(IsoBcSection *s)
{
uint8_t *magic_sec = (uint8_t *)(sec + ISO_SECTOR_SIZE);
if (s->unused || !s->sector_count) {
return false;
}
read_iso_sector(bswap32(s->load_rba), magic_sec,
"Failed to read image sector 0");
/* Checking bytes 8 - 32 for S390 Linux magic */
return !_memcmp(magic_sec + 8, linux_s390_magic, 24);
}
/* Location of the current sector of the directory */
static uint32_t sec_loc[ISO9660_MAX_DIR_DEPTH];
/* Offset in the current sector of the directory */
static uint32_t sec_offset[ISO9660_MAX_DIR_DEPTH];
/* Remained directory space in bytes */
static uint32_t dir_rem[ISO9660_MAX_DIR_DEPTH];
static inline uint32_t iso_get_file_size(uint32_t load_rba)
{
IsoVolDesc *vd = (IsoVolDesc *)sec;
IsoDirHdr *cur_record = &vd->vd.primary.rootdir;
uint8_t *temp = sec + ISO_SECTOR_SIZE;
int level = 0;
read_iso_sector(ISO_PRIMARY_VD_SECTOR, sec,
"Failed to read ISO primary descriptor");
sec_loc[0] = iso_733_to_u32(cur_record->ext_loc);
dir_rem[0] = 0;
sec_offset[0] = 0;
while (level >= 0) {
IPL_assert(sec_offset[level] <= ISO_SECTOR_SIZE,
"Directory tree structure violation");
cur_record = (IsoDirHdr *)(temp + sec_offset[level]);
if (sec_offset[level] == 0) {
read_iso_sector(sec_loc[level], temp,
"Failed to read ISO directory");
if (dir_rem[level] == 0) {
/* Skip self and parent records */
dir_rem[level] = iso_733_to_u32(cur_record->data_len) -
cur_record->dr_len;
sec_offset[level] += cur_record->dr_len;
cur_record = (IsoDirHdr *)(temp + sec_offset[level]);
dir_rem[level] -= cur_record->dr_len;
sec_offset[level] += cur_record->dr_len;
continue;
}
}
if (!cur_record->dr_len || sec_offset[level] == ISO_SECTOR_SIZE) {
/* Zero-padding and/or the end of current sector */
dir_rem[level] -= ISO_SECTOR_SIZE - sec_offset[level];
sec_offset[level] = 0;
sec_loc[level]++;
} else {
/* The directory record is valid */
if (load_rba == iso_733_to_u32(cur_record->ext_loc)) {
return iso_733_to_u32(cur_record->data_len);
}
dir_rem[level] -= cur_record->dr_len;
sec_offset[level] += cur_record->dr_len;
if (cur_record->file_flags & 0x2) {
/* Subdirectory */
if (level == ISO9660_MAX_DIR_DEPTH - 1) {
sclp_print("ISO-9660 directory depth limit exceeded\n");
} else {
level++;
sec_loc[level] = iso_733_to_u32(cur_record->ext_loc);
sec_offset[level] = 0;
dir_rem[level] = 0;
continue;
}
}
}
if (dir_rem[level] == 0) {
/* Nothing remaining */
level--;
read_iso_sector(sec_loc[level], temp,
"Failed to read ISO directory");
}
}
return 0;
}
static void load_iso_bc_entry(IsoBcSection *load)
{
IsoBcSection s = *load;
/*
* According to spec, extent for each file
* is padded and ISO_SECTOR_SIZE bytes aligned
*/
uint32_t blks_to_load = bswap16(s.sector_count) >> ET_SECTOR_SHIFT;
uint32_t real_size = iso_get_file_size(bswap32(s.load_rba));
if (real_size) {
/* Round up blocks to load */
blks_to_load = (real_size + ISO_SECTOR_SIZE - 1) / ISO_SECTOR_SIZE;
sclp_print("ISO boot image size verified\n");
} else {
sclp_print("ISO boot image size could not be verified\n");
}
read_iso_boot_image(bswap32(s.load_rba),
(void *)((uint64_t)bswap16(s.load_segment)),
blks_to_load);
/* Trying to get PSW at zero address */
if (*((uint64_t *)0) & IPL_PSW_MASK) {
jump_to_IPL_code((*((uint64_t *)0)) & 0x7fffffff);
}
/* Try default linux start address */
jump_to_IPL_code(KERN_IMAGE_START);
}
static uint32_t find_iso_bc(void)
{
IsoVolDesc *vd = (IsoVolDesc *)sec;
uint32_t block_num = ISO_PRIMARY_VD_SECTOR;
if (virtio_read_many(block_num++, sec, 1)) {
/* If primary vd cannot be read, there is no boot catalog */
return 0;
}
while (is_iso_vd_valid(vd) && vd->type != VOL_DESC_TERMINATOR) {
if (vd->type == VOL_DESC_TYPE_BOOT) {
IsoVdElTorito *et = &vd->vd.boot;
if (!_memcmp(&et->el_torito[0], el_torito_magic, 32)) {
return bswap32(et->bc_offset);
}
}
read_iso_sector(block_num++, sec,
"Failed to read ISO volume descriptor");
}
return 0;
}
static IsoBcSection *find_iso_bc_entry(void)
{
IsoBcEntry *e = (IsoBcEntry *)sec;
uint32_t offset = find_iso_bc();
int i;
if (!offset) {
return NULL;
}
read_iso_sector(offset, sec, "Failed to read El Torito boot catalog");
if (!is_iso_bc_valid(e)) {
/* The validation entry is mandatory */
panic("No valid boot catalog found!\n");
return NULL;
}
/*
* Each entry has 32 bytes size, so one sector cannot contain > 64 entries.
* We consider only boot catalogs with no more than 64 entries.
*/
for (i = 1; i < ISO_BC_ENTRY_PER_SECTOR; i++) {
if (e[i].id == ISO_BC_BOOTABLE_SECTION) {
if (is_iso_bc_entry_compatible(&e[i].body.sect)) {
return &e[i].body.sect;
}
}
}
panic("No suitable boot entry found on ISO-9660 media!\n");
return NULL;
}
static void ipl_iso_el_torito(void)
{
IsoBcSection *s = find_iso_bc_entry();
if (s) {
load_iso_bc_entry(s);
/* no return */
}
}
/***********************************************************************
* Bus specific IPL sequences
*/
static void zipl_load_vblk(void)
{
if (virtio_guessed_disk_nature()) {
virtio_assume_iso9660();
}
ipl_iso_el_torito();
if (virtio_guessed_disk_nature()) {
sclp_print("Using guessed DASD geometry.\n");
virtio_assume_eckd();
}
ipl_eckd();
}
static void zipl_load_vscsi(void)
{
if (virtio_get_block_size() == VIRTIO_ISO_BLOCK_SIZE) {
/* Is it an ISO image in non-CD drive? */
ipl_iso_el_torito();
}
sclp_print("Using guessed DASD geometry.\n");
virtio_assume_eckd();
ipl_eckd();
}
/***********************************************************************
* IPL starts here
*/
void zipl_load(void)
{
VDev *vdev = virtio_get_device();
if (vdev->is_cdrom) {
ipl_iso_el_torito();
panic("\n! Cannot IPL this ISO image !\n");
}
if (virtio_get_device_type() == VIRTIO_ID_NET) {
jump_to_IPL_code(vdev->netboot_start_addr);
}
ipl_scsi();
switch (virtio_get_device_type()) {
case VIRTIO_ID_BLOCK:
zipl_load_vblk();
break;
case VIRTIO_ID_SCSI:
zipl_load_vscsi();
break;
default:
panic("\n! Unknown IPL device type !\n");
}
panic("\n* this can never happen *\n");
}