u-boot/common/bloblist.c

// SPDX-License-Identifier: GPL-2.0+ BSD-3-Clause
/*
 * Copyright 2018 Google, Inc
 * Written by Simon Glass <sjg@chromium.org>
 */

#define LOG_DEBUG
#define LOG_CATEGORY	LOGC_BLOBLIST

#include <common.h>
#include <bloblist.h>
#include <log.h>
#include <malloc.h>
#include <mapmem.h>
#include <spl.h>
#include <asm/global_data.h>
#include <u-boot/crc.h>

/*
 * A bloblist is a single contiguous chunk of memory with a header
 * (struct bloblist_hdr) and a number of blobs in it.
 *
 * Each blob starts on a BLOBLIST_ALIGN boundary relative to the start of the
 * bloblist and consists of a struct bloblist_rec, some padding to the required
 * alignment for the blog and then the actual data. The padding ensures that the
 * start address of the data in each blob is aligned as required. Note that
 * each blob's *data* is aligned to BLOBLIST_ALIGN regardless of the alignment
 * of the bloblist itself or the blob header.
 *
 * So far, only BLOBLIST_ALIGN alignment is supported.
 */

DECLARE_GLOBAL_DATA_PTR;

static struct tag_name {
	enum bloblist_tag_t tag;
	const char *name;
} tag_name[] = {
	{ BLOBLISTT_NONE, "(none)" },

	/* BLOBLISTT_AREA_FIRMWARE_TOP */

	/* BLOBLISTT_AREA_FIRMWARE */
	{ BLOBLISTT_ACPI_GNVS, "ACPI GNVS" },
	{ BLOBLISTT_INTEL_VBT, "Intel Video-BIOS table" },
	{ BLOBLISTT_TPM2_TCG_LOG, "TPM v2 log space" },
	{ BLOBLISTT_TCPA_LOG, "TPM log space" },
	{ BLOBLISTT_ACPI_TABLES, "ACPI tables for x86" },
	{ BLOBLISTT_SMBIOS_TABLES, "SMBIOS tables for x86" },
	{ BLOBLISTT_VBOOT_CTX, "Chrome OS vboot context" },

	/* BLOBLISTT_PROJECT_AREA */
	{ BLOBLISTT_U_BOOT_SPL_HANDOFF, "SPL hand-off" },

	/* BLOBLISTT_VENDOR_AREA */
};

const char *bloblist_tag_name(enum bloblist_tag_t tag)
{
	int i;

	for (i = 0; i < ARRAY_SIZE(tag_name); i++) {
		if (tag_name[i].tag == tag)
			return tag_name[i].name;
	}

	return "invalid";
}

static struct bloblist_rec *bloblist_first_blob(struct bloblist_hdr *hdr)
{
	if (hdr->alloced <= hdr->hdr_size)
		return NULL;
	return (struct bloblist_rec *)((void *)hdr + hdr->hdr_size);
}

static ulong bloblist_blob_end_ofs(struct bloblist_hdr *hdr,
				   struct bloblist_rec *rec)
{
	ulong offset;

	offset = (void *)rec - (void *)hdr;
	offset += rec->hdr_size + ALIGN(rec->size, BLOBLIST_ALIGN);

	return offset;
}

static struct bloblist_rec *bloblist_next_blob(struct bloblist_hdr *hdr,
					       struct bloblist_rec *rec)
{
	ulong offset = bloblist_blob_end_ofs(hdr, rec);

	if (offset >= hdr->alloced)
		return NULL;
	return (struct bloblist_rec *)((void *)hdr + offset);
}

#define foreach_rec(_rec, _hdr) \
	for (_rec = bloblist_first_blob(_hdr); \
	     _rec; \
	     _rec = bloblist_next_blob(_hdr, _rec))

static struct bloblist_rec *bloblist_findrec(uint tag)
{
	struct bloblist_hdr *hdr = gd->bloblist;
	struct bloblist_rec *rec;

	if (!hdr)
		return NULL;

	foreach_rec(rec, hdr) {
		if (rec->tag == tag)
			return rec;
	}

	return NULL;
}

static int bloblist_addrec(uint tag, int size, int align,
			   struct bloblist_rec **recp)
{
	struct bloblist_hdr *hdr = gd->bloblist;
	struct bloblist_rec *rec;
	int data_start, new_alloced;

	if (!align)
		align = BLOBLIST_ALIGN;

	/* Figure out where the new data will start */
	data_start = map_to_sysmem(hdr) + hdr->alloced + sizeof(*rec);

	/* Align the address and then calculate the offset from ->alloced */
	data_start = ALIGN(data_start, align) - map_to_sysmem(hdr);

	/* Calculate the new allocated total */
	new_alloced = data_start + ALIGN(size, align);

	if (new_alloced > hdr->size) {
		log_err("Failed to allocate %x bytes size=%x, need size=%x\n",
			size, hdr->size, new_alloced);
		return log_msg_ret("bloblist add", -ENOSPC);
	}
	rec = (void *)hdr + hdr->alloced;

	rec->tag = tag;
	rec->hdr_size = data_start - hdr->alloced;
	rec->size = size;
	rec->spare = 0;

	/* Zero the record data */
	memset((void *)rec + rec->hdr_size, '\0', rec->size);

	hdr->alloced = new_alloced;
	*recp = rec;

	return 0;
}

static int bloblist_ensurerec(uint tag, struct bloblist_rec **recp, int size,
			      int align)
{
	struct bloblist_rec *rec;

	rec = bloblist_findrec(tag);
	if (rec) {
		if (size && size != rec->size) {
			*recp = rec;
			return -ESPIPE;
		}
	} else {
		int ret;

		ret = bloblist_addrec(tag, size, align, &rec);
		if (ret)
			return ret;
	}
	*recp = rec;

	return 0;
}

void *bloblist_find(uint tag, int size)
{
	struct bloblist_rec *rec;

	rec = bloblist_findrec(tag);
	if (!rec)
		return NULL;
	if (size && size != rec->size)
		return NULL;

	return (void *)rec + rec->hdr_size;
}

void *bloblist_add(uint tag, int size, int align)
{
	struct bloblist_rec *rec;

	if (bloblist_addrec(tag, size, align, &rec))
		return NULL;

	return (void *)rec + rec->hdr_size;
}

int bloblist_ensure_size(uint tag, int size, int align, void **blobp)
{
	struct bloblist_rec *rec;
	int ret;

	ret = bloblist_ensurerec(tag, &rec, size, align);
	if (ret)
		return ret;
	*blobp = (void *)rec + rec->hdr_size;

	return 0;
}

void *bloblist_ensure(uint tag, int size)
{
	struct bloblist_rec *rec;

	if (bloblist_ensurerec(tag, &rec, size, 0))
		return NULL;

	return (void *)rec + rec->hdr_size;
}

int bloblist_ensure_size_ret(uint tag, int *sizep, void **blobp)
{
	struct bloblist_rec *rec;
	int ret;

	ret = bloblist_ensurerec(tag, &rec, *sizep, 0);
	if (ret == -ESPIPE)
		*sizep = rec->size;
	else if (ret)
		return ret;
	*blobp = (void *)rec + rec->hdr_size;

	return 0;
}

static int bloblist_resize_rec(struct bloblist_hdr *hdr,
			       struct bloblist_rec *rec,
			       int new_size)
{
	int expand_by;	/* Number of bytes to expand by (-ve to contract) */
	int new_alloced;	/* New value for @hdr->alloced */
	ulong next_ofs;	/* Offset of the record after @rec */

	expand_by = ALIGN(new_size - rec->size, BLOBLIST_ALIGN);
	new_alloced = ALIGN(hdr->alloced + expand_by, BLOBLIST_ALIGN);
	if (new_size < 0) {
		log_debug("Attempt to shrink blob size below 0 (%x)\n",
			  new_size);
		return log_msg_ret("size", -EINVAL);
	}
	if (new_alloced > hdr->size) {
		log_err("Failed to allocate %x bytes size=%x, need size=%x\n",
			new_size, hdr->size, new_alloced);
		return log_msg_ret("alloc", -ENOSPC);
	}

	/* Move the following blobs up or down, if this is not the last */
	next_ofs = bloblist_blob_end_ofs(hdr, rec);
	if (next_ofs != hdr->alloced) {
		memmove((void *)hdr + next_ofs + expand_by,
			(void *)hdr + next_ofs, new_alloced - next_ofs);
	}
	hdr->alloced = new_alloced;

	/* Zero the new part of the blob */
	if (expand_by > 0) {
		memset((void *)rec + rec->hdr_size + rec->size, '\0',
		       new_size - rec->size);
	}

	/* Update the size of this blob */
	rec->size = new_size;

	return 0;
}

int bloblist_resize(uint tag, int new_size)
{
	struct bloblist_hdr *hdr = gd->bloblist;
	struct bloblist_rec *rec;
	int ret;

	rec = bloblist_findrec(tag);
	if (!rec)
		return log_msg_ret("find", -ENOENT);
	ret = bloblist_resize_rec(hdr, rec, new_size);
	if (ret)
		return log_msg_ret("resize", ret);

	return 0;
}

static u32 bloblist_calc_chksum(struct bloblist_hdr *hdr)
{
	struct bloblist_rec *rec;
	u32 chksum;

	chksum = crc32(0, (unsigned char *)hdr,
		       offsetof(struct bloblist_hdr, chksum));
	foreach_rec(rec, hdr) {
		chksum = crc32(chksum, (void *)rec, rec->hdr_size);
		chksum = crc32(chksum, (void *)rec + rec->hdr_size, rec->size);
	}

	return chksum;
}

int bloblist_new(ulong addr, uint size, uint flags)
{
	struct bloblist_hdr *hdr;

	if (size < sizeof(*hdr))
		return log_ret(-ENOSPC);
	if (addr & (BLOBLIST_ALIGN - 1))
		return log_ret(-EFAULT);
	hdr = map_sysmem(addr, size);
	memset(hdr, '\0', sizeof(*hdr));
	hdr->version = BLOBLIST_VERSION;
	hdr->hdr_size = sizeof(*hdr);
	hdr->flags = flags;
	hdr->magic = BLOBLIST_MAGIC;
	hdr->size = size;
	hdr->alloced = hdr->hdr_size;
	hdr->chksum = 0;
	gd->bloblist = hdr;

	return 0;
}

int bloblist_check(ulong addr, uint size)
{
	struct bloblist_hdr *hdr;
	u32 chksum;

	hdr = map_sysmem(addr, sizeof(*hdr));
	if (hdr->magic != BLOBLIST_MAGIC)
		return log_msg_ret("Bad magic", -ENOENT);
	if (hdr->version != BLOBLIST_VERSION)
		return log_msg_ret("Bad version", -EPROTONOSUPPORT);
	if (size && hdr->size != size)
		return log_msg_ret("Bad size", -EFBIG);
	chksum = bloblist_calc_chksum(hdr);
	if (hdr->chksum != chksum) {
		log_err("Checksum %x != %x\n", hdr->chksum, chksum);
		return log_msg_ret("Bad checksum", -EIO);
	}
	gd->bloblist = hdr;

	return 0;
}

int bloblist_finish(void)
{
	struct bloblist_hdr *hdr = gd->bloblist;

	hdr->chksum = bloblist_calc_chksum(hdr);
	log_debug("Finished bloblist size %lx at %lx\n", (ulong)hdr->size,
		  (ulong)map_to_sysmem(hdr));

	return 0;
}

ulong bloblist_get_base(void)
{
	return map_to_sysmem(gd->bloblist);
}

ulong bloblist_get_size(void)
{
	struct bloblist_hdr *hdr = gd->bloblist;

	return hdr->size;
}

void bloblist_get_stats(ulong *basep, ulong *sizep, ulong *allocedp)
{
	struct bloblist_hdr *hdr = gd->bloblist;

	*basep = map_to_sysmem(gd->bloblist);
	*sizep = hdr->size;
	*allocedp = hdr->alloced;
}

static void show_value(const char *prompt, ulong value)
{
	printf("%s:%*s %-5lx  ", prompt, 8 - (int)strlen(prompt), "", value);
	print_size(value, "\n");
}

void bloblist_show_stats(void)
{
	ulong base, size, alloced;

	bloblist_get_stats(&base, &size, &alloced);
	printf("base:     %lx\n", base);
	show_value("size", size);
	show_value("alloced", alloced);
	show_value("free", size - alloced);
}

void bloblist_show_list(void)
{
	struct bloblist_hdr *hdr = gd->bloblist;
	struct bloblist_rec *rec;

	printf("%-8s  %8s   Tag Name\n", "Address", "Size");
	for (rec = bloblist_first_blob(hdr); rec;
	     rec = bloblist_next_blob(hdr, rec)) {
		printf("%08lx  %8x  %4x %s\n",
		       (ulong)map_to_sysmem((void *)rec + rec->hdr_size),
		       rec->size, rec->tag, bloblist_tag_name(rec->tag));
	}
}

void bloblist_reloc(void *to, uint to_size, void *from, uint from_size)
{
	struct bloblist_hdr *hdr;

	memcpy(to, from, from_size);
	hdr = to;
	hdr->size = to_size;
}

int bloblist_init(void)
{
	bool fixed = IS_ENABLED(CONFIG_BLOBLIST_FIXED);
	int ret = -ENOENT;
	ulong addr, size;
	bool expected;

	/**
	 * We don't expect to find an existing bloblist in the first phase of
	 * U-Boot that runs. Also we have no way to receive the address of an
	 * allocated bloblist from a previous stage, so it must be at a fixed
	 * address.
	 */
	expected = fixed && !u_boot_first_phase();
	if (spl_prev_phase() == PHASE_TPL && !IS_ENABLED(CONFIG_TPL_BLOBLIST))
		expected = false;
	if (fixed)
		addr = IF_ENABLED_INT(CONFIG_BLOBLIST_FIXED,
				      CONFIG_BLOBLIST_ADDR);
	size = CONFIG_BLOBLIST_SIZE;
	if (expected) {
		ret = bloblist_check(addr, size);
		if (ret) {
			log_warning("Expected bloblist at %lx not found (err=%d)\n",
				    addr, ret);
		} else {
			/* Get the real size, if it is not what we expected */
			size = gd->bloblist->size;
		}
	}
	if (ret) {
		if (CONFIG_IS_ENABLED(BLOBLIST_ALLOC)) {
			void *ptr = memalign(BLOBLIST_ALIGN, size);

			if (!ptr)
				return log_msg_ret("alloc", -ENOMEM);
			addr = map_to_sysmem(ptr);
		} else if (!fixed) {
			return log_msg_ret("!fixed", ret);
		}
		log_debug("Creating new bloblist size %lx at %lx\n", size,
			  addr);
		ret = bloblist_new(addr, size, 0);
	} else {
		log_debug("Found existing bloblist size %lx at %lx\n", size,
			  addr);
	}

	return ret;
}