Hi Jassi,
On Mon, Jan 02, 2023 at 12:26:40PM -0600, Jassi Brar wrote:
> Instead of each i/f having to implement their own meta-data verification
> and storage, move the logic in common code. This simplifies the i/f code
> much simpler and compact.
>
> Signed-off-by: Jassi Brar <jaswinder.si...@linaro.org>
> ---
> drivers/fwu-mdata/fwu-mdata-uclass.c | 34 +++++++
> include/fwu.h | 41 ++++++++
> lib/fwu_updates/fwu.c | 142 ++++++++++++++++++++++++++-
> 3 files changed, 213 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/fwu-mdata/fwu-mdata-uclass.c
> b/drivers/fwu-mdata/fwu-mdata-uclass.c
> index b477e9603f..e03773c584 100644
> --- a/drivers/fwu-mdata/fwu-mdata-uclass.c
> +++ b/drivers/fwu-mdata/fwu-mdata-uclass.c
> @@ -16,6 +16,40 @@
> #include <linux/types.h>
> #include <u-boot/crc.h>
[...]
> + * fwu_sync_mdata() - Update given meta-data partition(s) with the copy
> provided
> + * @mdata: FWU metadata structure
> + * @part: Bitmask of FWU metadata partitions to be written to
> + *
> + * Return: 0 if OK, -ve on error
> + */
> +static int fwu_sync_mdata(struct fwu_mdata *mdata, int part)
> +{
> + void *buf = &mdata->version;
> + int err = 0;
> +
> + /*
> + * Calculate the crc32 for the updated FWU metadata
> + * and put the updated value in the FWU metadata crc32
> + * field
> + */
> + mdata->crc32 = crc32(0, buf, sizeof(*mdata) - sizeof(u32));
> +
> + if (part & PRIMARY_PART)
> + err = fwu_write_mdata(g_dev, mdata, true);
> +
> + if (err) {
> + log_err("Unable to write primary mdata\n");
> + return err;
> + }
> +
> + if (part & SECONDARY_PART)
> + err = fwu_write_mdata(g_dev, mdata, false);
> +
> + if (err) {
> + log_err("Unable to write secondary mdata\n");
> + return err;
> + }
Can we write this
err = fwu_write_mdata(g_dev, mdata, part & PRIMARY_PART ? true: false);
if (err)
log_err("Unable to write %s partition\n", part & PRIMARY_PART ? "primary":
"secondary" );
....
> +
> + /* update the cached copy of meta-data */
> + memcpy(&g_mdata, mdata, sizeof(struct fwu_mdata));
> +
> + return 0;
> +}
> +
> +static inline int mdata_crc_check(struct fwu_mdata *mdata)
> +{
> + void *buf = &mdata->version;
> + u32 calc_crc32 = crc32(0, buf, sizeof(*mdata) - sizeof(u32));
> +
> + return calc_crc32 == mdata->crc32 ? 0 : -EINVAL;
> +}
> +
> +/**
> + * fwu_get_verified_mdata() - Read, verify and return the FWU metadata
> + *
> + * Read both the metadata copies from the storage media, verify their
> checksum,
> + * and ascertain that both copies match. If one of the copies has gone bad,
> + * restore it from the good copy.
> + *
> + * Return: 0 if OK, -ve on error
> + */
> +int fwu_get_verified_mdata(struct fwu_mdata *mdata)
> +{
> + int err;
> + bool pri_ok, sec_ok;
> + struct fwu_mdata s, *p_mdata, *s_mdata;
> +
> + p_mdata = &g_mdata;
> + s_mdata = &s;
Why are we defining it like this? Readability to have pointers for primary
and secondary metadata?
> +
> + /* if mdata already read and ready */
> + err = mdata_crc_check(p_mdata);
> + if (!err)
> + goto ret_mdata;
Shouldn't we check the secondary metadata ? At least that's what the old
fwu_check_mdata_validity() was doing.
> + /* else read, verify and, if needed, fix mdata */
> +
> + pri_ok = false;
> + err = fwu_read_mdata(g_dev, p_mdata, true);
> + if (!err) {
> + err = mdata_crc_check(p_mdata);
> + if (!err)
> + pri_ok = true;
> + else
> + log_debug("primary mdata: crc32 failed\n");
> + }
> +
> + sec_ok = false;
> + err = fwu_read_mdata(g_dev, s_mdata, false);
> + if (!err) {
> + err = mdata_crc_check(s_mdata);
> + if (!err)
> + sec_ok = true;
> + else
> + log_debug("secondary mdata: crc32 failed\n");
> + }
> +
> + if (pri_ok && sec_ok) {
> + /*
> + * Before returning, check that both the
> + * FWU metadata copies are the same.
> + */
> + err = memcmp(p_mdata, s_mdata, sizeof(struct fwu_mdata));
> + if (!err)
> + goto ret_mdata;
> +
> + /*
> + * If not, populate the secondary partition from the
> + * primary partition copy.
> + */
> + log_info("Both FWU metadata copies are valid but do not
> match.");
> + log_info(" Restoring the secondary partition from the
> primary\n");
> + sec_ok = false;
> + }
> +
> + if (!pri_ok) {
> + memcpy(p_mdata, s_mdata, sizeof(struct fwu_mdata));
> + err = fwu_sync_mdata(p_mdata, PRIMARY_PART);
> + if (err)
> + goto ret_mdata;
The error print here is a bit misleading. It's a failed write, not a crc32
mismatch
> + }
> +
> + if (!sec_ok) {
> + memcpy(s_mdata, p_mdata, sizeof(struct fwu_mdata));
> + err = fwu_sync_mdata(s_mdata, SECONDARY_PART);
> + if (err)
> + goto ret_mdata;
> + }
> +
> +ret_mdata:
> + if (err)
> + log_debug("mdata : crc32 failed\n");
> + else if (mdata)
> + memcpy(mdata, p_mdata, sizeof(struct fwu_mdata));
> +
> + return err;
> +}
> +
> /**
> * fwu_verify_mdata() - Verify the FWU metadata
> * @mdata: FWU metadata structure
> --
> 2.34.1
>
Regards
/Ilias
