There isn't really a formal interface for dealing with EFI variables
or struct efivar_entry. Historically, this has led to various bits of
code directly accessing the generic EFI variable ops, which inherently
ties it to specific EFI variable operations instead of indirectly
using whatever ops were registered with register_efivars(). This lead
to the efivarfs code only working with the generic EFI variable ops
and not CONFIG_GOOGLE_SMI.
Encapsulate everything that needs to access '__efivars' inside an
efivar_entry_* API and use the new API in the pstore, sysfs and
efivarfs code.
Much of the efivars code had to be rewritten to use this new API. For
instance, it is now up to the users of the API to build the initial
list of EFI variables in their efivar_init() callback function. The
variable list needs to be passed to efivar_init() which allows us to
keep work arounds for things like implementation bugs in
GetNextVariable() in a central location.
Allowing users of the API to use a callback function to build the list
greatly benefits the efivarfs code which needs to allocate inodes and
dentries for every variable. It previously did this in a racy way
because the code ran without holding the variable spinlock. Both the
sysfs and efivarfs code maintain their own lists which means the two
interfaces can be running simultaneously without interference, though
it should be noted that because no synchronisation is performed it is
very easy to create inconsistencies. efibootmgr doesn't currently use
efivarfs and users are likely to also require the old sysfs interface,
so it makes sense to allow both to be built.
Reviewed-by: Tom Gundersen <teg@jklm.no>
Tested-by: Tom Gundersen <teg@jklm.no>
Cc: Seiji Aguchi <seiji.aguchi@hds.com>
Cc: Matthew Garrett <mjg59@srcf.ucam.org>
Cc: Jeremy Kerr <jk@ozlabs.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Mike Waychison <mikew@google.com>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
There are currently two implementations of the utf16 string functions.
Somewhat confusingly, they've got different names.
Centralise the functions in efi.h.
Reviewed-by: Tom Gundersen <teg@jklm.no>
Tested-by: Tom Gundersen <teg@jklm.no>
Reviewed-by: Mike Waychison <mikew@google.com>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Use min_t() macro instead of min() to fix a build warning:
CC drivers/firmware/google/gsmi.o
drivers/firmware/google/gsmi.c: In function ‘gsmi_get_variable’:
drivers/firmware/google/gsmi.c:348: warning: comparison of distinct
pointer types lacks a cast
Signed-off-by: Maxin B. John <maxin.john@gmail.com>
Acked-By: Mike Waychison <mikew@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This file really needs the full module.h header file present, but
was just getting it implicitly before. Fix it up in advance so we
avoid build failures once the cleanup commit is present.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Modify function parameter type to match expected type. Fixes a
build warning:
drivers/firmware/google/gsmi.c:473: warning: initialization from incompatible pointer type
Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Cc: Mike Waychison <mikew@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch removes sysfs entries in gsmi_exit() and gsmi_init() error path.
Also move the driver successfully loaded message to the end of gsmi_init()
and return proper error if register_efivars() fails.
Signed-off-by: Axel Lin <axel.lin@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The "gsmi" driver bridges userland with firmware specific routines for
accessing hardware.
Currently, this driver only supports NVRAM and eventlog information.
Deprecated functions have been removed from the driver, though their
op-codes are left in place so that they are not re-used.
This driver works by trampolining into the firmware via the smi_command
outlined in the FADT table. Three protocols are used due to various
limitations over time, but all are included herein.
This driver should only ever load on Google boards, identified by either
a "Google, Inc." board vendor string in DMI, or "GOOGLE" in the OEM
strings of the FADT ACPI table. This logic happens in
gsmi_system_valid().
Signed-off-by: Duncan Laurie <dlaurie@google.com>
Signed-off-by: Aaron Durbin <adurbin@google.com>
Signed-off-by: Mike Waychison <mikew@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>