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authorAaron Durbin <adurbin@chromium.org>2015-03-05 14:11:27 -0600
committerAaron Durbin <adurbin@chromium.org>2015-04-22 17:54:41 +0200
commit20686d851ce450750039f5f871160d49118a2210 (patch)
treecabba57012853074cbf31e4a82938c7357c78696 /src/lib/imd.c
parent818e928d12be9376476ee299fccf9cfe47abb1f2 (diff)
downloadcoreboot-20686d851ce450750039f5f871160d49118a2210.tar.xz
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>
Diffstat (limited to 'src/lib/imd.c')
-rw-r--r--src/lib/imd.c481
1 files changed, 481 insertions, 0 deletions
diff --git a/src/lib/imd.c b/src/lib/imd.c
new file mode 100644
index 0000000000..ff3aa75a64
--- /dev/null
+++ b/src/lib/imd.c
@@ -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;
+}