From 20686d851ce450750039f5f871160d49118a2210 Mon Sep 17 00:00:00 2001 From: Aaron Durbin Date: Thu, 5 Mar 2015 14:11:27 -0600 Subject: 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 Reviewed-on: http://review.coreboot.org/8621 Tested-by: build bot (Jenkins) Reviewed-by: Marc Jones --- src/include/imd.h | 139 ++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 139 insertions(+) create mode 100644 src/include/imd.h (limited to 'src/include/imd.h') diff --git a/src/include/imd.h b/src/include/imd.h new file mode 100644 index 0000000000..8d5c4522b7 --- /dev/null +++ b/src/include/imd.h @@ -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 +#include + +/* + * 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_ */ -- cgit v1.2.3