[RESEND RFC PATCH 04/10] FWU: Add metadata access functions for GPT partitioned block devices
Sughosh Ganu
sughosh.ganu at linaro.org
Thu Nov 25 08:12:56 CET 2021
In the FWU Multi Bank Update feature, the information about the
updatable images is stored as part of the metadata, on a separate
partition. Add functions for reading from and writing to the metadata
when the updatable images and the metadata are stored on a block
device which is formated with GPT based partition scheme.
Signed-off-by: Sughosh Ganu <sughosh.ganu at linaro.org>
---
lib/fwu_updates/fwu_metadata_gpt_blk.c | 716 +++++++++++++++++++++++++
1 file changed, 716 insertions(+)
create mode 100644 lib/fwu_updates/fwu_metadata_gpt_blk.c
diff --git a/lib/fwu_updates/fwu_metadata_gpt_blk.c b/lib/fwu_updates/fwu_metadata_gpt_blk.c
new file mode 100644
index 0000000000..98cc53f706
--- /dev/null
+++ b/lib/fwu_updates/fwu_metadata_gpt_blk.c
@@ -0,0 +1,716 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (c) 2021, Linaro Limited
+ */
+
+#include <blk.h>
+#include <efi_loader.h>
+#include <fwu_metadata.h>
+#include <malloc.h>
+#include <memalign.h>
+#include <part.h>
+#include <part_efi.h>
+
+#include <linux/errno.h>
+#include <linux/types.h>
+#include <u-boot/crc.h>
+
+#define PRIMARY_VALID 0x1
+#define SECONDARY_VALID 0x2
+
+#define MDATA_READ (u8)0x1
+#define MDATA_WRITE (u8)0x2
+
+#define IMAGE_ACCEPT_SET (u8)0x1
+#define IMAGE_ACCEPT_CLEAR (u8)0x2
+
+static int gpt_verify_metadata(struct fwu_metadata *metadata, bool pri_part)
+{
+ u32 calc_crc32;
+ void *buf;
+
+ buf = &metadata->version;
+ calc_crc32 = crc32(0, buf, sizeof(*metadata) - sizeof(u32));
+
+ if (calc_crc32 != metadata->crc32) {
+ log_err("crc32 check failed for %s metadata partition\n",
+ pri_part ? "primary" : "secondary");
+ return -1;
+ }
+
+ return 0;
+}
+
+static int gpt_get_metadata_partitions(struct blk_desc *desc,
+ u32 *primary_mpart,
+ u32 *secondary_mpart)
+{
+ int i, ret;
+ u32 nparts, mparts;
+ gpt_entry *gpt_pte = NULL;
+ const efi_guid_t fwu_metadata_guid = FWU_METADATA_GUID;
+
+ ALLOC_CACHE_ALIGN_BUFFER_PAD(gpt_header, gpt_head, 1,
+ desc->blksz);
+
+ ret = get_gpt_hdr_parts(desc, gpt_head, &gpt_pte);
+ if (ret < 0) {
+ log_err("Error getting GPT header and partitions\n");
+ ret = -EIO;
+ goto out;
+ }
+
+ nparts = gpt_head->num_partition_entries;
+ for (i = 0, mparts = 0; i < nparts; i++) {
+ if (!guidcmp(&fwu_metadata_guid,
+ &gpt_pte[i].partition_type_guid)) {
+ ++mparts;
+ if (!*primary_mpart)
+ *primary_mpart = i + 1;
+ else
+ *secondary_mpart = i + 1;
+ }
+ }
+
+ if (mparts != 2) {
+ log_err("Expect two copies of the metadata instead of %d\n",
+ mparts);
+ ret = -EINVAL;
+ } else {
+ ret = 0;
+ }
+out:
+ free(gpt_pte);
+
+ return ret;
+}
+
+static int gpt_get_metadata_disk_part(struct blk_desc *desc,
+ struct disk_partition *info,
+ u32 part_num)
+{
+ int ret;
+ char *metadata_guid_str = "8a7a84a0-8387-40f6-ab41-a8b9a5a60d23";
+
+ ret = part_get_info(desc, part_num, info);
+ if (ret < 0) {
+ log_err("Unable to get the partition info for the metadata part %d",
+ part_num);
+ return -1;
+ }
+
+ /* Check that it is indeed the metadata partition */
+ if (!strncmp(info->type_guid, metadata_guid_str, UUID_STR_LEN)) {
+ /* Found the metadata partition */
+ return 0;
+ }
+
+ return -1;
+}
+
+static int gpt_read_write_metadata(struct blk_desc *desc,
+ struct fwu_metadata *metadata,
+ u8 access, u32 part_num)
+{
+ int ret;
+ u32 len, blk_start, blkcnt;
+ struct disk_partition info;
+
+ ALLOC_CACHE_ALIGN_BUFFER_PAD(struct fwu_metadata, mdata, 1, desc->blksz);
+
+ ret = gpt_get_metadata_disk_part(desc, &info, part_num);
+ if (ret < 0) {
+ printf("Unable to get the metadata partition\n");
+ return -ENODEV;
+ }
+
+ len = sizeof(*metadata);
+ blkcnt = BLOCK_CNT(len, desc);
+ if (blkcnt > info.size) {
+ log_err("Block count exceeds metadata partition size\n");
+ return -ERANGE;
+ }
+
+ blk_start = info.start;
+ if (access == MDATA_READ) {
+ if (blk_dread(desc, blk_start, blkcnt, mdata) != blkcnt) {
+ log_err("Error reading metadata from the device\n");
+ return -EIO;
+ }
+ memcpy(metadata, mdata, sizeof(struct fwu_metadata));
+ } else {
+ if (blk_dwrite(desc, blk_start, blkcnt, metadata) != blkcnt) {
+ log_err("Error writing metadata to the device\n");
+ return -EIO;
+ }
+ }
+
+ return 0;
+}
+
+static int gpt_read_metadata(struct blk_desc *desc,
+ struct fwu_metadata *metadata, u32 part_num)
+{
+ return gpt_read_write_metadata(desc, metadata, MDATA_READ, part_num);
+}
+
+static int gpt_write_metadata_partition(struct blk_desc *desc,
+ struct fwu_metadata *metadata,
+ u32 part_num)
+{
+ return gpt_read_write_metadata(desc, metadata, MDATA_WRITE, part_num);
+}
+
+static int gpt_update_metadata(struct fwu_metadata *metadata)
+{
+ int ret;
+ struct blk_desc *desc;
+ u32 primary_mpart, secondary_mpart;
+
+ ret = fwu_plat_get_blk_desc(&desc);
+ if (ret < 0) {
+ log_err("Block device not found\n");
+ return -ENODEV;
+ }
+
+ primary_mpart = secondary_mpart = 0;
+ ret = gpt_get_metadata_partitions(desc, &primary_mpart,
+ &secondary_mpart);
+
+ if (ret < 0) {
+ log_err("Error getting the metadata partitions\n");
+ return -ENODEV;
+ }
+
+ /* First write the primary partition*/
+ ret = gpt_write_metadata_partition(desc, metadata, primary_mpart);
+ if (ret < 0) {
+ log_err("Updating primary metadata partition failed\n");
+ return ret;
+ }
+
+ /* And now the replica */
+ ret = gpt_write_metadata_partition(desc, metadata, secondary_mpart);
+ if (ret < 0) {
+ log_err("Updating secondary metadata partition failed\n");
+ return ret;
+ }
+
+ return 0;
+}
+
+static int gpt_get_valid_metadata(struct fwu_metadata **metadata)
+{
+ int ret;
+ struct blk_desc *desc;
+ u32 primary_mpart, secondary_mpart;
+
+ ret = fwu_plat_get_blk_desc(&desc);
+ if (ret < 0) {
+ log_err("Block device not found\n");
+ return -ENODEV;
+ }
+
+ primary_mpart = secondary_mpart = 0;
+ ret = gpt_get_metadata_partitions(desc, &primary_mpart,
+ &secondary_mpart);
+
+ if (ret < 0) {
+ log_err("Error getting the metadata partitions\n");
+ return -ENODEV;
+ }
+
+ *metadata = malloc(sizeof(struct fwu_metadata));
+ if (!*metadata) {
+ log_err("Unable to allocate memory for reading metadata\n");
+ return -ENOMEM;
+ }
+
+ ret = gpt_read_metadata(desc, *metadata, primary_mpart);
+ if (ret < 0) {
+ log_err("Failed to read the metadata from the device\n");
+ return -EIO;
+ }
+
+ ret = gpt_verify_metadata(*metadata, 1);
+ if (!ret)
+ return 0;
+
+ /*
+ * Verification of the primary metadata copy failed.
+ * Try to read the replica.
+ */
+ memset(*metadata, 0, sizeof(struct fwu_metadata));
+ ret = gpt_read_metadata(desc, *metadata, secondary_mpart);
+ if (ret < 0) {
+ log_err("Failed to read the metadata from the device\n");
+ return -EIO;
+ }
+
+ ret = gpt_verify_metadata(*metadata, 0);
+ if (!ret)
+ return 0;
+
+ /* Both the metadata copies are corrupted. */
+ return -1;
+}
+
+static int gpt_check_metadata_validity(void)
+{
+ int ret;
+ struct blk_desc *desc;
+ struct fwu_metadata *pri_metadata;
+ struct fwu_metadata *secondary_metadata;
+ u32 primary_mpart, secondary_mpart;
+ u32 valid_partitions;
+
+ ret = fwu_plat_get_blk_desc(&desc);
+ if (ret < 0) {
+ log_err("Block device not found\n");
+ return -ENODEV;
+ }
+
+ /*
+ * Two metadata partitions are expected.
+ * If we don't have two, user needs to create
+ * them first
+ */
+ primary_mpart = secondary_mpart = 0;
+ valid_partitions = 0;
+ ret = gpt_get_metadata_partitions(desc, &primary_mpart,
+ &secondary_mpart);
+
+ if (ret < 0) {
+ log_err("Error getting the metadata partitions\n");
+ return -ENODEV;
+ }
+
+ pri_metadata = malloc(sizeof(*pri_metadata));
+ if (!pri_metadata) {
+ log_err("Unable to allocate memory for reading metadata\n");
+ return -ENOMEM;
+ }
+
+ secondary_metadata = malloc(sizeof(*secondary_metadata));
+ if (!secondary_metadata) {
+ log_err("Unable to allocate memory for reading metadata\n");
+ return -ENOMEM;
+ }
+
+ ret = gpt_read_metadata(desc, pri_metadata, primary_mpart);
+ if (ret < 0) {
+ log_err("Failed to read the metadata from the device\n");
+ ret = -EIO;
+ goto out;
+ }
+
+ ret = gpt_verify_metadata(pri_metadata, 1);
+ if (!ret)
+ valid_partitions |= PRIMARY_VALID;
+
+ /* Now check the secondary partition */
+ ret = gpt_read_metadata(desc, secondary_metadata, secondary_mpart);
+ if (ret < 0) {
+ log_err("Failed to read the metadata from the device\n");
+ ret = -EIO;
+ goto out;
+ }
+
+ ret = gpt_verify_metadata(secondary_metadata, 0);
+ if (!ret)
+ valid_partitions |= SECONDARY_VALID;
+
+ if (valid_partitions == (PRIMARY_VALID | SECONDARY_VALID)) {
+ ret = -1;
+ /*
+ * Before returning, check that both the
+ * metadata copies are the same. If not,
+ * the metadata copies need to be
+ * re-populated.
+ */
+ if (!memcmp(pri_metadata, secondary_metadata,
+ sizeof(*pri_metadata)))
+ ret = 0;
+ goto out;
+ } else if (valid_partitions == SECONDARY_VALID) {
+ ret = gpt_write_metadata_partition(desc, secondary_metadata,
+ primary_mpart);
+ if (ret < 0) {
+ log_err("Restoring primary metadata partition failed\n");
+ goto out;
+ }
+ } else if (valid_partitions == PRIMARY_VALID) {
+ ret = gpt_write_metadata_partition(desc, pri_metadata,
+ secondary_mpart);
+ if (ret < 0) {
+ log_err("Restoring secondary metadata partition failed\n");
+ goto out;
+ }
+ } else {
+ ret = -1;
+ }
+
+out:
+ free(pri_metadata);
+
+ return ret;
+}
+
+static int gpt_fill_partition_guid_array(struct blk_desc *desc,
+ efi_guid_t **part_guid_arr,
+ u32 *nparts)
+{
+ int ret, i;
+ u32 parts;
+ gpt_entry *gpt_pte = NULL;
+ const efi_guid_t null_guid = NULL_GUID;
+
+ ALLOC_CACHE_ALIGN_BUFFER_PAD(gpt_header, gpt_head, 1,
+ desc->blksz);
+
+ ret = get_gpt_hdr_parts(desc, gpt_head, &gpt_pte);
+ if (ret < 0) {
+ log_err("Error getting GPT header and partitions\n");
+ ret = -EIO;
+ goto out;
+ }
+
+ *nparts = gpt_head->num_partition_entries;
+
+ /*
+ * There could be a scenario where the number of partition entries
+ * configured in the GPT header is the default value of 128. Find
+ * the actual number of populated partitioned entries
+ */
+ for (i = 0, parts = 0; i < *nparts; i++) {
+ if (!guidcmp(&gpt_pte[i].partition_type_guid, &null_guid))
+ continue;
+ ++parts;
+ }
+
+ *nparts = parts;
+ *part_guid_arr = malloc(sizeof(efi_guid_t) * *nparts);
+ if (!part_guid_arr) {
+ log_err("Unable to allocate memory for guid array\n");
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ for (i = 0; i < *nparts; i++) {
+ guidcpy((*part_guid_arr + i),
+ &gpt_pte[i].partition_type_guid);
+ }
+
+out:
+ free(gpt_pte);
+ return ret;
+}
+
+int fwu_gpt_get_active_index(u32 *active_idx)
+{
+ int ret;
+ struct fwu_metadata *metadata;
+
+ ret = gpt_get_valid_metadata(&metadata);
+ if (ret < 0) {
+ log_err("Unable to get valid metadata\n");
+ goto out;
+ }
+
+ /*
+ * Found the metadata partition, now read the active_index
+ * value
+ */
+ *active_idx = metadata->active_index;
+ if (*active_idx > CONFIG_FWU_NUM_BANKS - 1) {
+ printf("Active index value read is incorrect\n");
+ ret = -EINVAL;
+ goto out;
+ }
+
+out:
+ free(metadata);
+
+ return ret;
+}
+
+static int gpt_get_image_alt_num(struct blk_desc *desc,
+ efi_guid_t image_type_id,
+ u32 update_bank, int *alt_no)
+{
+ int ret, i;
+ u32 nparts;
+ gpt_entry *gpt_pte = NULL;
+ struct fwu_metadata *metadata;
+ struct fwu_image_entry *img_entry;
+ struct fwu_image_bank_info *img_bank_info;
+ efi_guid_t unique_part_guid;
+ efi_guid_t image_guid = NULL_GUID;
+
+ ALLOC_CACHE_ALIGN_BUFFER_PAD(gpt_header, gpt_head, 1,
+ desc->blksz);
+
+ ret = gpt_get_valid_metadata(&metadata);
+ if (ret < 0) {
+ log_err("Unable to read valid metadata\n");
+ goto out;
+ }
+
+ /*
+ * The metadata has been read. Now get the image_uuid for the
+ * image with the update_bank.
+ */
+ for (i = 0; i < CONFIG_FWU_NUM_IMAGES_PER_BANK; i++) {
+ if (!guidcmp(&image_type_id,
+ &metadata->img_entry[i].image_type_uuid)) {
+ img_entry = &metadata->img_entry[i];
+ img_bank_info = &img_entry->img_bank_info[update_bank];
+ guidcpy(&image_guid, &img_bank_info->image_uuid);
+ }
+ }
+
+ /*
+ * Now read the GPT Partition Table Entries to find a matching
+ * partition with UniquePartitionGuid value. We need to iterate
+ * through all the GPT partitions since they might be in any
+ * order
+ */
+ ret = get_gpt_hdr_parts(desc, gpt_head, &gpt_pte);
+ if (ret < 0) {
+ log_err("Error getting GPT header and partitions\n");
+ ret = -EIO;
+ goto out;
+ }
+
+ nparts = gpt_head->num_partition_entries;
+
+ for (i = 0; i < nparts; i++) {
+ unique_part_guid = gpt_pte[i].unique_partition_guid;
+ if (!guidcmp(&unique_part_guid, &image_guid)) {
+ /* Found the partition */
+ *alt_no = i + 1;
+ break;
+ }
+ }
+
+ if (i == nparts) {
+ log_err("Partition with the image guid not found\n");
+ ret = -EINVAL;
+ }
+
+out:
+ free(metadata);
+ free(gpt_pte);
+ return ret;
+}
+
+int fwu_gpt_update_active_index(u32 active_idx)
+{
+ int ret;
+ void *buf;
+ u32 cur_active_index;
+ struct fwu_metadata *metadata;
+
+ if (active_idx > CONFIG_FWU_NUM_BANKS) {
+ printf("Active index value to be updated is incorrect\n");
+ return -1;
+ }
+
+ ret = gpt_get_valid_metadata(&metadata);
+ if (ret < 0) {
+ log_err("Unable to get valid metadata\n");
+ goto out;
+ }
+
+ /*
+ * Update the active index and previous_active_index fields
+ * in the metadata
+ */
+ cur_active_index = metadata->active_index;
+ metadata->active_index = active_idx;
+ metadata->previous_active_index = cur_active_index;
+
+ /*
+ * Calculate the crc32 for the updated metadata
+ * and put the updated value in the metadata crc32
+ * field
+ */
+ buf = &metadata->version;
+ metadata->crc32 = crc32(0, buf, sizeof(*metadata) - sizeof(u32));
+
+ /*
+ * Now write this updated metadata to both the
+ * metadata partitions
+ */
+ ret = gpt_update_metadata(metadata);
+ if (ret < 0) {
+ log_err("Failed to update metadata partitions\n");
+ ret = -EIO;
+ }
+
+out:
+ free(metadata);
+
+ return ret;
+}
+
+int fwu_gpt_fill_partition_guid_array(efi_guid_t **part_guid_arr, u32 *nparts)
+{
+ int ret;
+ struct blk_desc *desc;
+
+ ret = fwu_plat_get_blk_desc(&desc);
+ if (ret < 0) {
+ log_err("Block device not found\n");
+ return -ENODEV;
+ }
+
+ return gpt_fill_partition_guid_array(desc, part_guid_arr, nparts);
+}
+
+int fwu_gpt_get_image_alt_num(efi_guid_t image_type_id, u32 update_bank,
+ int *alt_no)
+{
+ int ret;
+ struct blk_desc *desc;
+
+ ret = fwu_plat_get_blk_desc(&desc);
+ if (ret < 0) {
+ log_err("Block device not found\n");
+ return -ENODEV;
+ }
+
+ return gpt_get_image_alt_num(desc, image_type_id, update_bank, alt_no);
+}
+
+int fwu_gpt_metadata_check(void)
+{
+ /*
+ * Check if both the copies of the metadata are valid.
+ * If one has gone bad, restore it from the other good
+ * copy.
+ */
+ return gpt_check_metadata_validity();
+}
+
+int fwu_gpt_get_metadata(struct fwu_metadata **metadata)
+{
+ return gpt_get_valid_metadata(metadata);
+}
+
+int fwu_gpt_revert_boot_index(u32 *active_idx)
+{
+ int ret;
+ void *buf;
+ u32 cur_active_index;
+ struct fwu_metadata *metadata;
+
+ ret = gpt_get_valid_metadata(&metadata);
+ if (ret < 0) {
+ log_err("Unable to get valid metadata\n");
+ goto out;
+ }
+
+ /*
+ * Swap the active index and previous_active_index fields
+ * in the metadata
+ */
+ cur_active_index = metadata->active_index;
+ metadata->active_index = metadata->previous_active_index;
+ metadata->previous_active_index = cur_active_index;
+ *active_idx = metadata->active_index;
+
+ /*
+ * Calculate the crc32 for the updated metadata
+ * and put the updated value in the metadata crc32
+ * field
+ */
+ buf = &metadata->version;
+ metadata->crc32 = crc32(0, buf, sizeof(*metadata) - sizeof(u32));
+
+ /*
+ * Now write this updated metadata to both the
+ * metadata partitions
+ */
+ ret = gpt_update_metadata(metadata);
+ if (ret < 0) {
+ log_err("Failed to update metadata partitions\n");
+ ret = -EIO;
+ }
+
+out:
+ free(metadata);
+
+ return ret;
+}
+
+static int fwu_gpt_set_clear_image_accept(efi_guid_t *img_type_id,
+ u32 bank, u8 action)
+{
+ void *buf;
+ int ret, i;
+ u32 nimages;
+ struct fwu_metadata *metadata;
+ struct fwu_image_entry *img_entry;
+ struct fwu_image_bank_info *img_bank_info;
+
+ ret = gpt_get_valid_metadata(&metadata);
+ if (ret < 0) {
+ log_err("Unable to get valid metadata\n");
+ goto out;
+ }
+
+ if (action == IMAGE_ACCEPT_SET)
+ bank = metadata->active_index;
+
+ nimages = CONFIG_FWU_NUM_IMAGES_PER_BANK;
+ img_entry = &metadata->img_entry[0];
+ for (i = 0; i < nimages; i++) {
+ if (!guidcmp(&img_entry[i].image_type_uuid, img_type_id)) {
+ img_bank_info = &img_entry[i].img_bank_info[bank];
+ if (action == IMAGE_ACCEPT_SET)
+ img_bank_info->accepted |= FWU_IMAGE_ACCEPTED;
+ else
+ img_bank_info->accepted = 0;
+
+ buf = &metadata->version;
+ metadata->crc32 = crc32(0, buf, sizeof(*metadata) -
+ sizeof(u32));
+
+ ret = gpt_update_metadata(metadata);
+ goto out;
+ }
+ }
+
+ /* Image not found */
+ ret = -EINVAL;
+
+out:
+ free(metadata);
+
+ return ret;
+}
+
+int fwu_gpt_accept_image(efi_guid_t *img_type_id)
+{
+ return fwu_gpt_set_clear_image_accept(img_type_id, 0,
+ IMAGE_ACCEPT_SET);
+}
+
+int fwu_gpt_clear_accept_image(efi_guid_t *img_type_id, u32 bank)
+{
+ return fwu_gpt_set_clear_image_accept(img_type_id, bank,
+ IMAGE_ACCEPT_CLEAR);
+}
+
+struct fwu_metadata_ops fwu_gpt_blk_ops = {
+ .get_active_index = fwu_gpt_get_active_index,
+ .update_active_index = fwu_gpt_update_active_index,
+ .fill_partition_guid_array = fwu_gpt_fill_partition_guid_array,
+ .get_image_alt_num = fwu_gpt_get_image_alt_num,
+ .metadata_check = fwu_gpt_metadata_check,
+ .revert_boot_index = fwu_gpt_revert_boot_index,
+ .set_accept_image = fwu_gpt_accept_image,
+ .clear_accept_image = fwu_gpt_clear_accept_image,
+ .get_metadata = fwu_gpt_get_metadata,
+};
--
2.17.1
More information about the U-Boot
mailing list