Hi Greg,
On Fri, Sep 08, 2023 at 10:30:54AM -0500, gjoyce@xxxxxxxxxxxxxxxxxx wrote:
> From: Greg Joyce <gjoyce@xxxxxxxxxxxxxxxxxx>
>
> Add read and write functions that allow SED Opal keys to stored
> in a permanent keystore.
>
> Signed-off-by: Greg Joyce <gjoyce@xxxxxxxxxxxxxxxxxx>
> Reviewed-by: Jonathan Derrick <jonathan.derrick@xxxxxxxxx>
> ---
> block/Makefile | 2 +-
> block/sed-opal-key.c | 24 ++++++++++++++++++++++++
> include/linux/sed-opal-key.h | 15 +++++++++++++++
> 3 files changed, 40 insertions(+), 1 deletion(-)
> create mode 100644 block/sed-opal-key.c
> create mode 100644 include/linux/sed-opal-key.h
>
> diff --git a/block/Makefile b/block/Makefile
> index 46ada9dc8bbf..ea07d80402a6 100644
> --- a/block/Makefile
> +++ b/block/Makefile
> @@ -34,7 +34,7 @@ obj-$(CONFIG_BLK_DEV_ZONED) += blk-zoned.o
> obj-$(CONFIG_BLK_WBT) += blk-wbt.o
> obj-$(CONFIG_BLK_DEBUG_FS) += blk-mq-debugfs.o
> obj-$(CONFIG_BLK_DEBUG_FS_ZONED)+= blk-mq-debugfs-zoned.o
> -obj-$(CONFIG_BLK_SED_OPAL) += sed-opal.o
> +obj-$(CONFIG_BLK_SED_OPAL) += sed-opal.o sed-opal-key.o
> obj-$(CONFIG_BLK_PM) += blk-pm.o
> obj-$(CONFIG_BLK_INLINE_ENCRYPTION) += blk-crypto.o blk-crypto-profile.o \
> blk-crypto-sysfs.o
> diff --git a/block/sed-opal-key.c b/block/sed-opal-key.c
> new file mode 100644
> index 000000000000..16f380164c44
> --- /dev/null
> +++ b/block/sed-opal-key.c
> @@ -0,0 +1,24 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * SED key operations.
> + *
> + * Copyright (C) 2022 IBM Corporation
> + *
> + * These are the accessor functions (read/write) for SED Opal
> + * keys. Specific keystores can provide overrides.
> + *
> + */
> +
> +#include <linux/kernel.h>
> +#include <linux/errno.h>
> +#include <linux/sed-opal-key.h>
> +
> +int __weak sed_read_key(char *keyname, char *key, u_int *keylen)
> +{
> + return -EOPNOTSUPP;
> +}
> +
> +int __weak sed_write_key(char *keyname, char *key, u_int keylen)
> +{
> + return -EOPNOTSUPP;
> +}
This change causes a build failure for certain clang configurations due
to an unfortunate issue [1] with recordmcount, clang's integrated
assembler, and object files that contain a section with only weak
functions/symbols (in this case, the .text section in sed-opal-key.c),
resulting in
Cannot find symbol for section 2: .text.
block/sed-opal-key.o: failed
when building this file.
Is there any real reason to have a separate translation unit for these
two functions versus just having them living in sed-opal.c? Those two
object files share the same Kconfig dependency. I am happy to send a
patch if that is an acceptable approach.
[1]: https://github.com/ClangBuiltLinux/linux/issues/981
Cheers,
Nathan
