coreboot: add imd library

The imd (internal memory database) library provides a way to
track memory regions by assigning ids to each region. The implementation
is a direct descendant of dynamic cbmem. The intent is to replace
the existing mechanisms which do similar things: dynamic cbmem, stage
cache, etc.

Differences between dynamic cbmem and imd:
- All structures/objects are relative to one another. There
  are no absolute pointers serialized to memory.
- Allow limiting the size of the idm. i.e. provide a maximum
  memory usage.
- Allow setting the size of the root structure which allows
  control of the number of allocations to track.

Change-Id: Id7438cff80d396a594d6a7330d09b45bb4fedf2e
Signed-off-by: Aaron Durbin <adurbin@chromium.org>
Reviewed-on: http://review.coreboot.org/8621
Tested-by: build bot (Jenkins)
Reviewed-by: Marc Jones <marc.jones@se-eng.com>
This commit is contained in:
Aaron Durbin 2015-03-05 14:11:27 -06:00
parent 818e928d12
commit 20686d851c
4 changed files with 625 additions and 0 deletions

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@ -57,6 +57,7 @@
#define CBMEM_ID_GDT 0x4c474454
#define CBMEM_ID_HOB_POINTER 0x484f4221
#define CBMEM_ID_IGD_OPREGION 0x4f444749
#define CBMEM_ID_IMD_ROOT 0xff4017ff
#define CBMEM_ID_MEMINFO 0x494D454D
#define CBMEM_ID_MPTABLE 0x534d5054
#define CBMEM_ID_MRCDATA 0x4d524344
@ -103,6 +104,7 @@ struct cbmem_id_to_name {
{ CBMEM_ID_ELOG, "ELOG " }, \
{ CBMEM_ID_FREESPACE, "FREE SPACE " }, \
{ CBMEM_ID_GDT, "GDT " }, \
{ CBMEM_ID_IMD_ROOT, "IMD ROOT " }, \
{ CBMEM_ID_MEMINFO, "MEM INFO " }, \
{ CBMEM_ID_MPTABLE, "SMP TABLE " }, \
{ CBMEM_ID_MRCDATA, "MRC DATA " }, \

139
src/include/imd.h Normal file
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@ -0,0 +1,139 @@
/*
* This file is part of the coreboot project.
*
* Copyright 2015 Google, Inc.
*
* 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.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc.
*/
#ifndef _IMD_H_
#define _IMD_H_
#include <stdint.h>
#include <stddef.h>
/*
* imd is an in-memory database/directory/datastore (whatever d word you
* desire). It grows downwards in memory from provided upper limit and
* root size. Each entry has a size alignment which is also provided by
* the caller.
*
* +----------------------+ <- upper_limit
* | +----| root pointer |
* | | +----------------------+
* | | | |--------+
* | +--->| root block |-----+ |
* | +----------------------+-----|--|--- root_size
* | | | | |
* | | | | |
* | | alloc N |<----+ |
* | +----------------------+ |
* | | | |
* | | | |
* \|/ | alloc N + 1 |<-------+
* v +----------------------+
*
* The root_size in imd_create_empty() encompasses the root pointer
* and root block. The root_size value, therefore, dictates the number
* of allocations maintained by the imd.
*/
/*
* NOTE: This API has the following calling conventions: all functions
* returning int supply 0 on success or < 0 on error.
*/
struct imd_entry;
struct imd;
/*
* Initialize handle to use for working with an imd. Upper limit is the
* exclusive address to start allocating down from. This function needs
* to be called at least once before any other imd related functions
* can be used.
*/
void imd_handle_init(struct imd *imd, void *upper_limit);
/*
* Initialize a handle with a shallow recovery. This function doesn't
* verify every entry, but it does set up the root pointer. Because of
* this behavior it's not very safe. However, the current CBMEM constraints
* demand having these semantics.
*/
void imd_handle_init_partial_recovery(struct imd *imd);
/*
* Create an empty imd with a specified root_size and each entry is aligned to
* the provided entry_align. As noted above the root size encompasses the
* root pointer and root block leading to the number of imd entries being a
* function of the root_size parameter.
*/
int imd_create_empty(struct imd *imd, size_t root_size, size_t entry_align);
/*
* Recover a previously created imd.
*/
int imd_recover(struct imd *imd);
/* Limit imd to provided max_size. */
int imd_limit_size(struct imd *imd, size_t max_size);
/* Lock down imd from further modifications. */
int imd_lockdown(struct imd *imd);
/* Fill in base address and size of region used by imd. */
int imd_region_used(struct imd *imd, void **base, size_t *size);
/* Add an entry to the imd. If id already exists NULL is returned. */
const struct imd_entry *imd_entry_add(const struct imd *imd, uint32_t id,
size_t size);
/* Locate an entry within the imd. NULL is returned when not found. */
const struct imd_entry *imd_entry_find(const struct imd *imd, uint32_t id);
/* Find an existing entry or add a new one. */
const struct imd_entry *imd_entry_find_or_add(const struct imd *imd,
uint32_t id, size_t size);
/* Returns size of entry or 0 on failure. */
size_t imd_entry_size(const struct imd *imd, const struct imd_entry *entry);
/* Returns pointer to region described by entry or NULL on failure. */
void *imd_entry_at(const struct imd *imd, const struct imd_entry *entry);
/* Attempt to remove entry from imd. */
int imd_entry_remove(const struct imd *imd, const struct imd_entry *entry);
/* Print the entry information provided by lookup with the specified size. */
struct imd_lookup {
uint32_t id;
const char *name;
};
int imd_print_entries(const struct imd *imd, const struct imd_lookup *lookup,
size_t size);
/*
* The struct imd is a handle for working with an in-memory directory.
*
* NOTE: Do not directly touch any fields within this structure. An imd pointer
* is meant to be opaque, but the fields are exposed for stack allocation.
*/
struct imd {
uintptr_t limit;
void *r;
};
#endif /* _IMD_H_ */

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@ -102,6 +102,9 @@ ramstage-y += b64_decode.c
romstage-y += cbmem_common.c dynamic_cbmem.c
ramstage-y += cbmem_common.c dynamic_cbmem.c
romstage-y += imd.c
ramstage-y += imd.c
ramstage-y += hexdump.c
romstage-y += hexdump.c

481
src/lib/imd.c Normal file
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@ -0,0 +1,481 @@
/*
* This file is part of the coreboot project.
*
* Copyright 2015 Google, Inc.
*
* 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.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc.
*/
#include <assert.h>
#include <cbmem.h>
#include <console/console.h>
#include <imd.h>
#include <stdlib.h>
#include <string.h>
/* For more details on implementation and usage please see the imd.h header. */
static const uint32_t IMD_ROOT_PTR_MAGIC = 0xc0389481;
static const uint32_t IMD_ENTRY_MAGIC = ~0xc0389481;
static const size_t LIMIT_ALIGN = 4096;
/* In-memory data structures. */
struct imd_root_pointer {
uint32_t magic;
/* Relative to upper limit/offset. */
int32_t root_offset;
} __attribute__((packed));
struct imd_entry {
uint32_t magic;
/* start is located relative to imd_root */
int32_t start_offset;
uint32_t size;
uint32_t id;
} __attribute__((packed));
struct imd_root {
uint32_t max_entries;
uint32_t num_entries;
uint32_t flags;
uint32_t entry_align;
/* Used for fixing the size of an imd. Relative to the root. */
int32_t max_offset;
struct imd_entry entries[0];
} __attribute__((packed));
#define IMD_FLAG_LOCKED 1
static void *relative_pointer(void *base, ssize_t offset)
{
intptr_t b = (intptr_t)base;
b += offset;
return (void *)b;
}
static bool imd_root_pointer_valid(const struct imd_root_pointer *rp)
{
return !!(rp->magic == IMD_ROOT_PTR_MAGIC);
}
static struct imd_root *imd_root(const struct imd *imd)
{
return imd->r;
}
/*
* The root pointer is relative to the upper limit of the imd. i.e. It sits
* just below the upper limit.
*/
static struct imd_root_pointer *imd_get_root_pointer(const struct imd *imd)
{
struct imd_root_pointer *rp;
rp = relative_pointer((void *)imd->limit, -sizeof(*rp));
return rp;
}
static void imd_link_root(struct imd_root_pointer *rp, struct imd_root *r)
{
rp->magic = IMD_ROOT_PTR_MAGIC;
rp->root_offset = (int32_t)((intptr_t)r - (intptr_t)rp);
}
static void imd_entry_assign(struct imd_entry *e, uint32_t id,
ssize_t offset, size_t size)
{
e->magic = IMD_ENTRY_MAGIC;
e->start_offset = offset;
e->size = size;
e->id = id;
}
static bool root_is_locked(const struct imd_root *r)
{
return !!(r->flags & IMD_FLAG_LOCKED);
}
static struct imd_entry *root_last_entry(struct imd_root *r)
{
return &r->entries[r->num_entries - 1];
}
/* Initialize imd handle. */
void imd_handle_init(struct imd *imd, void *upper_limit)
{
uintptr_t limit = (uintptr_t)upper_limit;
/* Upper limit is aligned down to 4KiB */
imd->limit = ALIGN_DOWN(limit, LIMIT_ALIGN);
imd->r = NULL;
}
void imd_handle_init_partial_recovery(struct imd *imd)
{
struct imd_root_pointer *rp;
imd_handle_init(imd, (void *)imd->limit);
rp = imd_get_root_pointer(imd);
imd->r = relative_pointer(rp, rp->root_offset);
}
int imd_create_empty(struct imd *imd, size_t root_size, size_t entry_align)
{
struct imd_root_pointer *rp;
struct imd_root *r;
struct imd_entry *e;
ssize_t root_offset;
size_t entries_size;
if (!imd->limit)
return -1;
/* root_size and entry_align should be a power of 2. */
assert(IS_POWER_OF_2(root_size));
assert(IS_POWER_OF_2(entry_align));
/*
* root_size needs to be large enough to accomodate root pointer and
* root book keeping structure. The caller needs to ensure there's
* enough room for tracking individual allocations.
*/
if (root_size < (sizeof(*rp) + sizeof(*r)))
return -1;
/* For simplicity don't allow sizes or alignments to exceed LIMIT_ALIGN. */
if (root_size > LIMIT_ALIGN || entry_align > LIMIT_ALIGN)
return -1;
/* Additionally, don't handle an entry alignment > root_size. */
if (entry_align > root_size)
return -1;
rp = imd_get_root_pointer(imd);
root_offset = -(ssize_t)root_size;
/* Set root pointer. */
imd->r = relative_pointer((void *)imd->limit, root_offset);
r = imd_root(imd);
imd_link_root(rp, r);
memset(r, 0, sizeof(*r));
r->entry_align = entry_align;
/* Calculate size left for entries. */
entries_size = root_size;
entries_size -= sizeof(*rp);
entries_size -= sizeof(*r);
r->max_entries = entries_size / sizeof(r->entries[0]);
/* Fill in first entry covering the root region. */
r->num_entries = 1;
e = &r->entries[0];
imd_entry_assign(e, CBMEM_ID_IMD_ROOT, 0, root_size);
printk(BIOS_DEBUG, "IMD: root @ %p %u entries.\n", r, r->max_entries);
return 0;
}
int imd_limit_size(struct imd *imd, size_t max_size)
{
struct imd_root *r;
ssize_t smax_size;
size_t root_size;
r = imd_root(imd);
if (r == NULL)
return -1;
root_size = imd->limit - (uintptr_t)r;
if (max_size < root_size)
return -1;
/* Take into account the root size. */
smax_size = max_size - root_size;
smax_size = -smax_size;
r->max_offset = smax_size;
return 0;
}
int imd_recover(struct imd *imd)
{
struct imd_root_pointer *rp;
struct imd_root *r;
uintptr_t low_limit;
size_t i;
if (!imd->limit);
return -1;
rp = imd_get_root_pointer(imd);
if (!imd_root_pointer_valid(rp))
return -1;
r = relative_pointer(rp, rp->root_offset);
/* Confirm the root and root pointer are just under the limit. */
if (ALIGN_UP((uintptr_t)&r->entries[r->max_entries], LIMIT_ALIGN) !=
imd->limit)
return -1;
if (r->num_entries > r->max_entries)
return -1;
/* Entry alignment should be power of 2. */
if (!IS_POWER_OF_2(r->entry_align))
return -1;
low_limit = (uintptr_t)relative_pointer(r, r->max_offset);
/* If no max_offset then lowest limit is 0. */
if (low_limit == (uintptr_t)r)
low_limit = 0;
for (i = 0; i < r->num_entries; i++) {
uintptr_t start_addr;
const struct imd_entry *e = &r->entries[i];
if (e->magic != IMD_ENTRY_MAGIC)
return -1;
start_addr = (uintptr_t)relative_pointer(r, e->start_offset);
if (start_addr < low_limit)
return -1;
if (start_addr >= imd->limit ||
(start_addr + e->size) > imd->limit)
return -1;
}
/* Set root pointer. */
imd->r = r;
return 0;
}
int imd_lockdown(struct imd *imd)
{
struct imd_root *r;
r = imd_root(imd);
if (r == NULL)
return -1;
r->flags |= IMD_FLAG_LOCKED;
return 0;
}
int imd_region_used(struct imd *imd, void **base, size_t *size)
{
struct imd_root *r;
struct imd_entry *e;
void *low_addr;
size_t sz_used;
if (!imd->limit)
return -1;
r = imd_root(imd);
if (r == NULL)
return -1;
/* Use last entry to obtain lowest address. */
e = root_last_entry(r);
low_addr = relative_pointer(r, e->start_offset);
/* Total size used is the last entry's base up to the limit. */
sz_used = imd->limit - (uintptr_t)low_addr;
*base = low_addr;
*size = sz_used;
return 0;
}
static struct imd_entry *imd_entry_add_to_root(struct imd_root *r, uint32_t id,
size_t size)
{
struct imd_entry *entry;
struct imd_entry *last_entry;
ssize_t e_offset;
size_t used_size;
if (r->num_entries == r->max_entries)
return NULL;
/* Determine total size taken up by entry. */
used_size = ALIGN_UP(size, r->entry_align);
last_entry = root_last_entry(r);
/* See if size overflows imd total size. */
if (r->max_offset != 0) {
size_t remaining = last_entry->start_offset - r->max_offset;
if (used_size > remaining)
return NULL;
}
/*
* Determine if offset field overflows. All offsets should be lower
* than the previous one.
*/
e_offset = last_entry->start_offset;
e_offset -= (ssize_t)used_size;
if (e_offset > last_entry->start_offset)
return NULL;
entry = root_last_entry(r) + 1;
r->num_entries++;
imd_entry_assign(entry, id, e_offset, size);
return entry;
}
const struct imd_entry *imd_entry_add(const struct imd *imd, uint32_t id,
size_t size)
{
struct imd_root *r;
r = imd_root(imd);
if (r == NULL)
return NULL;
if (root_is_locked(r))
return NULL;
return imd_entry_add_to_root(r, id, size);
}
const struct imd_entry *imd_entry_find(const struct imd *imd, uint32_t id)
{
struct imd_root *r;
struct imd_entry *e;
size_t i;
r = imd_root(imd);
if (r == NULL)
return NULL;
e = NULL;
/* Skip first entry covering the root. */
for (i = 1; i < r->num_entries; i++) {
if (id == r->entries[i].id) {
e = &r->entries[i];
break;
}
}
return e;
}
const struct imd_entry *imd_entry_find_or_add(const struct imd *imd,
uint32_t id, size_t size)
{
const struct imd_entry *e;
e = imd_entry_find(imd, id);
if (e != NULL)
return e;
return imd_entry_add(imd, id, size);
}
size_t imd_entry_size(const struct imd *imd, const struct imd_entry *entry)
{
return entry->size;
}
void *imd_entry_at(const struct imd *imd, const struct imd_entry *entry)
{
struct imd_root *r;
r = imd_root(imd);
if (r == NULL)
return NULL;
return relative_pointer(r, entry->start_offset);
}
int imd_entry_remove(const struct imd *imd, const struct imd_entry *entry)
{
struct imd_root *r;
r = imd_root(imd);
if (r == NULL)
return -1;
if (root_is_locked(r))
return -1;
if (entry != root_last_entry(r))
return -1;
r->num_entries--;
return 0;
}
int imd_print_entries(const struct imd *imd, const struct imd_lookup *lookup,
size_t size)
{
struct imd_root *r;
size_t i;
size_t j;
if (imd == NULL)
return -1;
r = imd_root(imd);
if (r == NULL)
return -1;
for (i = 0; i < r->num_entries; i++) {
const char *name = NULL;
const struct imd_entry *e = &r->entries[i];
for (j = 0; j < size; j++) {
if (lookup[j].id == e->id) {
name = lookup[j].name;
break;
}
}
if (name == NULL)
printk(BIOS_DEBUG, "%08x ", e->id);
else
printk(BIOS_DEBUG, "%s", name);
printk(BIOS_DEBUG, "%2zu. ", i);
printk(BIOS_DEBUG, "%p ", imd_entry_at(imd, e));
printk(BIOS_DEBUG, "%08zx\n", imd_entry_size(imd, e));
}
return 0;
}