diff --git a/stand/i386/libi386/Makefile b/stand/i386/libi386/Makefile --- a/stand/i386/libi386/Makefile +++ b/stand/i386/libi386/Makefile @@ -7,6 +7,7 @@ SRCS+= biosacpi.c SRCS+= biosdisk.c SRCS+= biosmem.c +SRCS+= biosmemdisk.c SRCS+= biospci.c SRCS+= biospnp.c SRCS+= biossmap.c diff --git a/stand/i386/libi386/biosmemdisk.c b/stand/i386/libi386/biosmemdisk.c new file mode 100644 --- /dev/null +++ b/stand/i386/libi386/biosmemdisk.c @@ -0,0 +1,140 @@ +/*- + * Copyright (c) 2020 Richard Russo + * + * SPDX-License-Identifier: BSD-2-Clause + */ + +/* + * Source of information: https://repo.or.cz/syslinux.git + * + * Implements the MEMDISK protocol from syslinux, found in doc/memdisk.txt + * (search MEMDISK info structure). Since we validate the pointer to the mBFT, a + * minimum version of 3.85 is needed. Note: All this could be done in the + * kernel, since we don't have hooks to use this inside the boot loader. The + * details of these structures can be found in memdisk/memdisk.inc (search + * for mBFT). + * + * The kernel could just grab the mBFT table, but instead relies on us finding + * it and setting the right env variables. + */ +#include +#include +#include +#include +#include "libi386.h" + +#include "platform/acfreebsd.h" +#include "acconfig.h" +#define ACPI_SYSTEM_XFACE +#include "actypes.h" +#include "actbl.h" + +struct memdisk_info { + uint32_t mdi_13h_hook_ptr; /* not included in mdi_length! */ + uint16_t mdi_length; + uint8_t mdi_minor; + uint8_t mdi_major; + uint32_t mdi_disk_ptr; + uint32_t mdi_disk_sectors; + uint32_t mdi_far_ptr_cmdline; + uint32_t mdi_old_int13h; + uint32_t mdi_old_int15h; + uint16_t mdi_dos_mem_before; + uint8_t mdi_boot_loader_id; + uint8_t mdi_sector_size; /* Code below assumes this is last */ +} __attribute__((packed)); + +struct safe_13h_hook { + char sh_jmp[3]; + char sh_id[8]; + char sh_vendor[8]; + uint16_t sh_next_offset; + uint16_t sh_next_segment; + uint32_t sh_flags; + uint32_t sh_mbft; +} __attribute__((packed)); + +/* + * Maximum length of INT 13 entries we'll chase. Real disks are on this list, + * potentially, so we may have to look through them to find the memdisk. + */ +#define MEMDISK_MAX 32 + +/* + * Scan for MEMDISK virtual block devices + */ +void +biosmemdisk_detect(void) +{ + char line[80], scratch[80]; + int hook = 0, count = 0, sector_size; + uint16_t segment, offset; + struct safe_13h_hook *probe; + ACPI_TABLE_HEADER *mbft; + uint8_t *cp, sum; + struct memdisk_info *mdi; + + /* + * Walk through the int13 handler linked list, looking for possible + * MEMDISKs. + * + * The max is arbitrary to ensure termination. + */ + offset = *(uint16_t *)PTOV(0x13 * 4); + segment = *(uint16_t *)PTOV(0x13 * 4 + 2); + while (hook < MEMDISK_MAX && !(segment == 0 && offset == 0)) { + /* + * Walk the linked list, making sure each node has the right + * signature and only looking at MEMDISK nodes. + */ + probe = (struct safe_13h_hook *)PTOV(segment * 16 + offset); + if (memcmp(probe->sh_id, "$INT13SF", sizeof(probe->sh_id)) != 0) { + printf("Found int 13h unsafe hook at %p (%x:%x)\n", + probe, segment, offset); + break; + } + if (memcmp(probe->sh_vendor, "MEMDISK ", sizeof(probe->sh_vendor)) != 0) + goto end_of_loop; + + /* + * If it is a memdisk, make sure the mBFT signature is correct + * and its checksum is right. + */ + mbft = (ACPI_TABLE_HEADER *)PTOV(probe->sh_mbft); + if (memcmp(mbft->Signature, "mBFT", sizeof(mbft->Signature)) != 0) + goto end_of_loop; + sum = 0; + cp = (uint8_t *)mbft; + for (int idx = 0; idx < mbft->Length; ++idx) + sum += *(cp + idx); + if (sum != 0) + goto end_of_loop; + + /* + * The memdisk info follows the ACPI_TABLE_HEADER in the mBFT + * section. If the sector size is present and non-zero use it + * otherwise assume 512. + */ + mdi = (struct memdisk_info *)PTOV(probe->sh_mbft + sizeof(*mbft)); + sector_size = 512; + if (mdi->mdi_length + sizeof(mdi->mdi_13h_hook_ptr) >= sizeof(*mdi) && + mdi->mdi_sector_size != 0) + sector_size = 1 << mdi->mdi_sector_size; + + printf("memdisk %d.%d disk at %#x (%d sectors = %d bytes)\n", + mdi->mdi_major, mdi->mdi_minor, mdi->mdi_disk_ptr, + mdi->mdi_disk_sectors, mdi->mdi_disk_sectors * sector_size); + + snprintf(line, sizeof(line), "hint.md.%d.physaddr", count); + snprintf(scratch, sizeof(scratch), "0x%08x", mdi->mdi_disk_ptr); + setenv(line, scratch, 1); + snprintf(line, sizeof(line), "hint.md.%d.len", count); + snprintf(scratch, sizeof(scratch), "%d", mdi->mdi_disk_sectors * sector_size); + setenv(line, scratch, 1); + count++; +end_of_loop: + hook++; + offset = probe->sh_next_offset; + segment = probe->sh_next_segment; + } +} diff --git a/stand/i386/libi386/libi386.h b/stand/i386/libi386/libi386.h --- a/stand/i386/libi386/libi386.h +++ b/stand/i386/libi386/libi386.h @@ -149,3 +149,5 @@ vm_offset_t *kernend, int add_smap); void pxe_enable(void *pxeinfo); + +void biosmemdisk_detect(void); diff --git a/stand/i386/loader/main.c b/stand/i386/loader/main.c --- a/stand/i386/loader/main.c +++ b/stand/i386/loader/main.c @@ -251,6 +251,9 @@ initial_bootinfo->bi_extmem = bios_extmem / 1024; } + /* detect MEMDISK virtual disks */ + biosmemdisk_detect(); + /* detect SMBIOS for future reference */ smbios_detect(NULL); diff --git a/sys/dev/md/md.c b/sys/dev/md/md.c --- a/sys/dev/md/md.c +++ b/sys/dev/md/md.c @@ -89,6 +89,8 @@ #include #include #include +#include +#include #include #include @@ -2082,8 +2084,10 @@ { caddr_t mod; u_char *ptr, *name, *type; + u_char scratch[40]; unsigned len; int i; + vm_offset_t paddr; /* figure out log2(NINDIR) */ for (i = NINDIR, nshift = -1; i; nshift++) @@ -2123,6 +2127,25 @@ sx_xunlock(&md_sx); } } + + /* + * Load up to 32 pre-loaded disks + */ + for (int i = 0; i < 32; i++) { + if (resource_long_value("md", i, "physaddr", + (long *) &paddr) != 0 || + resource_int_value("md", i, "len", &len) != 0) + break; + ptr = (char *)pmap_map(NULL, paddr, paddr + len, VM_PROT_READ); + if (ptr != NULL && len != 0) { + sprintf(scratch, "preload%d 0x%016jx", i, + (uintmax_t)paddr); + sx_xlock(&md_sx); + md_preloaded(ptr, len, scratch); + sx_xunlock(&md_sx); + } + } + status_dev = make_dev(&mdctl_cdevsw, INT_MAX, UID_ROOT, GID_WHEEL, 0600, MDCTL_NAME); g_topology_lock();