| /* |
| * This file is part of the coreboot project. |
| * |
| * Copyright (C) 2003 Eric W. Biederman <ebiederm@xmission.com> |
| * Copyright (C) 2009 Ron Minnich <rminnich@gmail.com> |
| * Copyright (C) 2016 George Trudeau <george.trudeau@usherbrooke.ca> |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License as published by |
| * the Free Software Foundation; version 2 of the License. |
| * |
| * This program is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| * GNU General Public License for more details. |
| */ |
| |
| #include <commonlib/compression.h> |
| #include <commonlib/endian.h> |
| #include <console/console.h> |
| #include <cpu/cpu.h> |
| #include <stdint.h> |
| #include <stdlib.h> |
| #include <string.h> |
| #include <symbols.h> |
| #include <cbfs.h> |
| #include <lib.h> |
| #include <bootmem.h> |
| #include <program_loading.h> |
| #include <timestamp.h> |
| |
| static const unsigned long lb_start = (unsigned long)&_program; |
| static const unsigned long lb_end = (unsigned long)&_eprogram; |
| |
| struct segment { |
| struct segment *next; |
| struct segment *prev; |
| unsigned long s_dstaddr; |
| unsigned long s_srcaddr; |
| unsigned long s_memsz; |
| unsigned long s_filesz; |
| int compression; |
| }; |
| |
| static void segment_insert_before(struct segment *seg, struct segment *new) |
| { |
| new->next = seg; |
| new->prev = seg->prev; |
| seg->prev->next = new; |
| seg->prev = new; |
| } |
| |
| static void segment_insert_after(struct segment *seg, struct segment *new) |
| { |
| new->next = seg->next; |
| new->prev = seg; |
| seg->next->prev = new; |
| seg->next = new; |
| } |
| |
| /* The problem: |
| * Static executables all want to share the same addresses |
| * in memory because only a few addresses are reliably present on |
| * a machine, and implementing general relocation is hard. |
| * |
| * The solution: |
| * - Allocate a buffer the size of the coreboot image plus additional |
| * required space. |
| * - Anything that would overwrite coreboot copy into the lower part of |
| * the buffer. |
| * - After loading an ELF image copy coreboot to the top of the buffer. |
| * - Then jump to the loaded image. |
| * |
| * Benefits: |
| * - Nearly arbitrary standalone executables can be loaded. |
| * - Coreboot is preserved, so it can be returned to. |
| * - The implementation is still relatively simple, |
| * and much simpler than the general case implemented in kexec. |
| */ |
| |
| static unsigned long bounce_size, bounce_buffer; |
| |
| static void get_bounce_buffer(unsigned long req_size) |
| { |
| unsigned long lb_size; |
| void *buffer; |
| |
| /* When the ramstage is relocatable there is no need for a bounce |
| * buffer. All payloads should not overlap the ramstage. |
| */ |
| if (IS_ENABLED(CONFIG_RELOCATABLE_RAMSTAGE)) { |
| bounce_buffer = ~0UL; |
| bounce_size = 0; |
| return; |
| } |
| |
| lb_size = lb_end - lb_start; |
| /* Plus coreboot size so I have somewhere |
| * to place a copy to return to. |
| */ |
| lb_size = req_size + lb_size; |
| |
| buffer = bootmem_allocate_buffer(lb_size); |
| |
| printk(BIOS_SPEW, "Bounce Buffer at %p, %lu bytes\n", buffer, lb_size); |
| |
| bounce_buffer = (uintptr_t)buffer; |
| bounce_size = req_size; |
| } |
| |
| static int overlaps_coreboot(struct segment *seg) |
| { |
| unsigned long start, end; |
| start = seg->s_dstaddr; |
| end = start + seg->s_memsz; |
| return !((end <= lb_start) || (start >= lb_end)); |
| } |
| |
| static int relocate_segment(unsigned long buffer, struct segment *seg) |
| { |
| /* Modify all segments that want to load onto coreboot |
| * to load onto the bounce buffer instead. |
| */ |
| /* ret: 1 : A new segment is inserted before the seg. |
| * 0 : A new segment is inserted after the seg, or no new one. |
| */ |
| unsigned long start, middle, end, ret = 0; |
| |
| printk(BIOS_SPEW, "lb: [0x%016lx, 0x%016lx)\n", |
| lb_start, lb_end); |
| |
| /* I don't conflict with coreboot so get out of here */ |
| if (!overlaps_coreboot(seg)) |
| return 0; |
| |
| if (!arch_supports_bounce_buffer()) |
| die ("bounce buffer not supported"); |
| |
| start = seg->s_dstaddr; |
| middle = start + seg->s_filesz; |
| end = start + seg->s_memsz; |
| |
| printk(BIOS_SPEW, "segment: [0x%016lx, 0x%016lx, 0x%016lx)\n", |
| start, middle, end); |
| |
| if (seg->compression == CBFS_COMPRESS_NONE) { |
| /* Slice off a piece at the beginning |
| * that doesn't conflict with coreboot. |
| */ |
| if (start < lb_start) { |
| struct segment *new; |
| unsigned long len = lb_start - start; |
| new = malloc(sizeof(*new)); |
| *new = *seg; |
| new->s_memsz = len; |
| seg->s_memsz -= len; |
| seg->s_dstaddr += len; |
| seg->s_srcaddr += len; |
| if (seg->s_filesz > len) { |
| new->s_filesz = len; |
| seg->s_filesz -= len; |
| } else { |
| seg->s_filesz = 0; |
| } |
| |
| /* Order by stream offset */ |
| segment_insert_before(seg, new); |
| |
| /* compute the new value of start */ |
| start = seg->s_dstaddr; |
| |
| printk(BIOS_SPEW, " early: [0x%016lx, 0x%016lx, 0x%016lx)\n", |
| new->s_dstaddr, |
| new->s_dstaddr + new->s_filesz, |
| new->s_dstaddr + new->s_memsz); |
| |
| ret = 1; |
| } |
| |
| /* Slice off a piece at the end |
| * that doesn't conflict with coreboot |
| */ |
| if (end > lb_end) { |
| unsigned long len = lb_end - start; |
| struct segment *new; |
| new = malloc(sizeof(*new)); |
| *new = *seg; |
| seg->s_memsz = len; |
| new->s_memsz -= len; |
| new->s_dstaddr += len; |
| new->s_srcaddr += len; |
| if (seg->s_filesz > len) { |
| seg->s_filesz = len; |
| new->s_filesz -= len; |
| } else { |
| new->s_filesz = 0; |
| } |
| /* Order by stream offset */ |
| segment_insert_after(seg, new); |
| |
| printk(BIOS_SPEW, " late: [0x%016lx, 0x%016lx, 0x%016lx)\n", |
| new->s_dstaddr, |
| new->s_dstaddr + new->s_filesz, |
| new->s_dstaddr + new->s_memsz); |
| } |
| } |
| |
| /* Now retarget this segment onto the bounce buffer */ |
| /* sort of explanation: the buffer is a 1:1 mapping to coreboot. |
| * so you will make the dstaddr be this buffer, and it will get copied |
| * later to where coreboot lives. |
| */ |
| seg->s_dstaddr = buffer + (seg->s_dstaddr - lb_start); |
| |
| printk(BIOS_SPEW, " bounce: [0x%016lx, 0x%016lx, 0x%016lx)\n", |
| seg->s_dstaddr, |
| seg->s_dstaddr + seg->s_filesz, |
| seg->s_dstaddr + seg->s_memsz); |
| |
| return ret; |
| } |
| |
| /* Decode a serialized cbfs payload segment |
| * from memory into native endianness. |
| */ |
| static void cbfs_decode_payload_segment(struct cbfs_payload_segment *segment, |
| const struct cbfs_payload_segment *src) |
| { |
| segment->type = read_be32(&src->type); |
| segment->compression = read_be32(&src->compression); |
| segment->offset = read_be32(&src->offset); |
| segment->load_addr = read_be64(&src->load_addr); |
| segment->len = read_be32(&src->len); |
| segment->mem_len = read_be32(&src->mem_len); |
| } |
| |
| static int build_self_segment_list( |
| struct segment *head, |
| struct cbfs_payload *cbfs_payload, uintptr_t *entry) |
| { |
| struct segment *new; |
| struct cbfs_payload_segment *current_segment, *first_segment, segment; |
| |
| memset(head, 0, sizeof(*head)); |
| head->next = head->prev = head; |
| |
| first_segment = &cbfs_payload->segments; |
| |
| for (current_segment = first_segment;; ++current_segment) { |
| printk(BIOS_DEBUG, |
| "Loading segment from ROM address 0x%p\n", |
| current_segment); |
| |
| cbfs_decode_payload_segment(&segment, current_segment); |
| |
| switch (segment.type) { |
| case PAYLOAD_SEGMENT_PARAMS: |
| printk(BIOS_DEBUG, " parameter section (skipped)\n"); |
| continue; |
| |
| case PAYLOAD_SEGMENT_CODE: |
| case PAYLOAD_SEGMENT_DATA: |
| printk(BIOS_DEBUG, " %s (compression=%x)\n", |
| segment.type == PAYLOAD_SEGMENT_CODE |
| ? "code" : "data", segment.compression); |
| |
| new = malloc(sizeof(*new)); |
| new->s_dstaddr = segment.load_addr; |
| new->s_memsz = segment.mem_len; |
| new->compression = segment.compression; |
| new->s_srcaddr = (uintptr_t) |
| ((unsigned char *)first_segment) |
| + segment.offset; |
| new->s_filesz = segment.len; |
| |
| printk(BIOS_DEBUG, " New segment dstaddr 0x%lx memsize 0x%lx srcaddr 0x%lx filesize 0x%lx\n", |
| new->s_dstaddr, new->s_memsz, new->s_srcaddr, new->s_filesz); |
| |
| /* Clean up the values */ |
| if (new->s_filesz > new->s_memsz) { |
| new->s_filesz = new->s_memsz; |
| printk(BIOS_DEBUG, |
| " cleaned up filesize 0x%lx\n", |
| new->s_filesz); |
| } |
| break; |
| |
| case PAYLOAD_SEGMENT_BSS: |
| printk(BIOS_DEBUG, " BSS 0x%p (%d byte)\n", (void *) |
| (intptr_t)segment.load_addr, segment.mem_len); |
| |
| new = malloc(sizeof(*new)); |
| new->s_filesz = 0; |
| new->s_srcaddr = (uintptr_t) |
| ((unsigned char *)first_segment) |
| + segment.offset; |
| new->s_dstaddr = segment.load_addr; |
| new->s_memsz = segment.mem_len; |
| new->compression = CBFS_COMPRESS_NONE; |
| break; |
| |
| case PAYLOAD_SEGMENT_ENTRY: |
| printk(BIOS_DEBUG, " Entry Point 0x%p\n", (void *) |
| (intptr_t)segment.load_addr); |
| |
| *entry = segment.load_addr; |
| /* Per definition, a payload always has the entry point |
| * as last segment. Thus, we use the occurrence of the |
| * entry point as break condition for the loop. |
| * Can we actually just look at the number of section? |
| */ |
| return 1; |
| |
| default: |
| /* We found something that we don't know about. Throw |
| * hands into the sky and run away! |
| */ |
| printk(BIOS_EMERG, "Bad segment type %x\n", |
| segment.type); |
| return -1; |
| } |
| |
| /* We have found another CODE, DATA or BSS segment */ |
| /* Insert new segment at the end of the list */ |
| segment_insert_before(head, new); |
| } |
| |
| return 1; |
| } |
| |
| static int load_self_segments( |
| struct segment *head, |
| struct prog *payload) |
| { |
| struct segment *ptr; |
| const unsigned long one_meg = (1UL << 20); |
| unsigned long bounce_high = lb_end; |
| |
| for(ptr = head->next; ptr != head; ptr = ptr->next) { |
| if (bootmem_region_targets_usable_ram(ptr->s_dstaddr, |
| ptr->s_memsz)) |
| continue; |
| |
| if (ptr->s_dstaddr < one_meg && |
| (ptr->s_dstaddr + ptr->s_memsz) <= one_meg) { |
| printk(BIOS_DEBUG, |
| "Payload being loaded below 1MiB " |
| "without region being marked as RAM usable.\n"); |
| continue; |
| } |
| |
| /* Payload segment not targeting RAM. */ |
| printk(BIOS_ERR, "SELF Payload doesn't target RAM:\n"); |
| printk(BIOS_ERR, "Failed Segment: 0x%lx, %lu bytes\n", |
| ptr->s_dstaddr, ptr->s_memsz); |
| bootmem_dump_ranges(); |
| return 0; |
| } |
| |
| for(ptr = head->next; ptr != head; ptr = ptr->next) { |
| /* |
| * Add segments to bootmem memory map before a bounce buffer is |
| * allocated so that there aren't conflicts with the actual |
| * payload. |
| */ |
| bootmem_add_range(ptr->s_dstaddr, ptr->s_memsz, |
| LB_MEM_UNUSABLE); |
| |
| if (!overlaps_coreboot(ptr)) |
| continue; |
| if (ptr->s_dstaddr + ptr->s_memsz > bounce_high) |
| bounce_high = ptr->s_dstaddr + ptr->s_memsz; |
| } |
| get_bounce_buffer(bounce_high - lb_start); |
| if (!bounce_buffer) { |
| printk(BIOS_ERR, "Could not find a bounce buffer...\n"); |
| return 0; |
| } |
| |
| for(ptr = head->next; ptr != head; ptr = ptr->next) { |
| unsigned char *dest, *src, *middle, *end; |
| size_t len, memsz; |
| printk(BIOS_DEBUG, "Loading Segment: addr: 0x%016lx memsz: 0x%016lx filesz: 0x%016lx\n", |
| ptr->s_dstaddr, ptr->s_memsz, ptr->s_filesz); |
| |
| /* Modify the segment to load onto the bounce_buffer if necessary. |
| */ |
| if (relocate_segment(bounce_buffer, ptr)) { |
| ptr = (ptr->prev)->prev; |
| continue; |
| } |
| |
| printk(BIOS_DEBUG, "Post relocation: addr: 0x%016lx memsz: 0x%016lx filesz: 0x%016lx\n", |
| ptr->s_dstaddr, ptr->s_memsz, ptr->s_filesz); |
| |
| /* Compute the boundaries of the segment */ |
| dest = (unsigned char *)(ptr->s_dstaddr); |
| src = (unsigned char *)(ptr->s_srcaddr); |
| len = ptr->s_filesz; |
| memsz = ptr->s_memsz; |
| end = dest + memsz; |
| |
| /* Copy data from the initial buffer */ |
| switch(ptr->compression) { |
| case CBFS_COMPRESS_LZMA: { |
| printk(BIOS_DEBUG, "using LZMA\n"); |
| timestamp_add_now(TS_START_ULZMA); |
| len = ulzman(src, len, dest, memsz); |
| timestamp_add_now(TS_END_ULZMA); |
| if (!len) /* Decompression Error. */ |
| return 0; |
| break; |
| } |
| case CBFS_COMPRESS_LZ4: { |
| printk(BIOS_DEBUG, "using LZ4\n"); |
| timestamp_add_now(TS_START_ULZ4F); |
| len = ulz4fn(src, len, dest, memsz); |
| timestamp_add_now(TS_END_ULZ4F); |
| if (!len) /* Decompression Error. */ |
| return 0; |
| break; |
| } |
| case CBFS_COMPRESS_NONE: { |
| printk(BIOS_DEBUG, "it's not compressed!\n"); |
| memcpy(dest, src, len); |
| break; |
| } |
| default: |
| printk(BIOS_INFO, "CBFS: Unknown compression type %d\n", ptr->compression); |
| return -1; |
| } |
| /* Calculate middle after any changes to len. */ |
| middle = dest + len; |
| printk(BIOS_SPEW, "[ 0x%08lx, %08lx, 0x%08lx) <- %08lx\n", |
| (unsigned long)dest, |
| (unsigned long)middle, |
| (unsigned long)end, |
| (unsigned long)src); |
| |
| /* Zero the extra bytes between middle & end */ |
| if (middle < end) { |
| printk(BIOS_DEBUG, "Clearing Segment: addr: 0x%016lx memsz: 0x%016lx\n", |
| (unsigned long)middle, (unsigned long)(end - middle)); |
| |
| /* Zero the extra bytes */ |
| memset(middle, 0, end - middle); |
| } |
| |
| /* Copy the data that's outside the area that shadows ramstage */ |
| printk(BIOS_DEBUG, "dest %p, end %p, bouncebuffer %lx\n", dest, end, bounce_buffer); |
| if ((unsigned long)end > bounce_buffer) { |
| if ((unsigned long)dest < bounce_buffer) { |
| unsigned char *from = dest; |
| unsigned char *to = (unsigned char*)(lb_start-(bounce_buffer-(unsigned long)dest)); |
| unsigned long amount = bounce_buffer-(unsigned long)dest; |
| printk(BIOS_DEBUG, "move prefix around: from %p, to %p, amount: %lx\n", from, to, amount); |
| memcpy(to, from, amount); |
| } |
| if ((unsigned long)end > bounce_buffer + (lb_end - lb_start)) { |
| unsigned long from = bounce_buffer + (lb_end - lb_start); |
| unsigned long to = lb_end; |
| unsigned long amount = (unsigned long)end - from; |
| printk(BIOS_DEBUG, "move suffix around: from %lx, to %lx, amount: %lx\n", from, to, amount); |
| memcpy((char*)to, (char*)from, amount); |
| } |
| } |
| |
| /* |
| * Each architecture can perform additonal operations |
| * on the loaded segment |
| */ |
| prog_segment_loaded((uintptr_t)dest, ptr->s_memsz, |
| ptr->next == head ? SEG_FINAL : 0); |
| } |
| |
| return 1; |
| } |
| |
| void *selfload(struct prog *payload) |
| { |
| uintptr_t entry = 0; |
| struct segment head; |
| void *data; |
| |
| data = rdev_mmap_full(prog_rdev(payload)); |
| |
| if (data == NULL) |
| return NULL; |
| |
| /* Preprocess the self segments */ |
| if (!build_self_segment_list(&head, data, &entry)) |
| goto out; |
| |
| /* Load the segments */ |
| if (!load_self_segments(&head, payload)) |
| goto out; |
| |
| printk(BIOS_SPEW, "Loaded segments\n"); |
| |
| rdev_munmap(prog_rdev(payload), data); |
| |
| /* Update the payload's area with the bounce buffer information. */ |
| prog_set_area(payload, (void *)(uintptr_t)bounce_buffer, bounce_size); |
| |
| return (void *)entry; |
| |
| out: |
| rdev_munmap(prog_rdev(payload), data); |
| return NULL; |
| } |