lib/vdso: Allow to add architecture-specific vdso data

The initial assumption that all VDSO related data can be completely generic
does not hold. S390 needs architecture specific storage to access the clock
steering information.

Add struct arch_vdso_data to the vdso data struct. For architectures which
do not need extra data this defaults to an empty struct. Architectures
which require it, enable CONFIG_ARCH_HAS_VDSO_DATA and provide their
specific struct in asm/vdso/data.h.

Signed-off-by: Sven Schnelle <svens@linux.ibm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20200804150124.41692-2-svens@linux.ibm.com
This commit is contained in:
Sven Schnelle 2020-08-04 17:01:22 +02:00 committed by Thomas Gleixner
parent 19d0070a27
commit d60d7de3e1
2 changed files with 13 additions and 0 deletions

View File

@ -975,6 +975,9 @@ config HAVE_SPARSE_SYSCALL_NR
entries at 4000, 5000 and 6000 locations. This option turns on syscall
related optimizations for a given architecture.
config ARCH_HAS_VDSO_DATA
bool
source "kernel/gcov/Kconfig"
source "scripts/gcc-plugins/Kconfig"

View File

@ -19,6 +19,12 @@
#include <vdso/time32.h>
#include <vdso/time64.h>
#ifdef CONFIG_ARCH_HAS_VDSO_DATA
#include <asm/vdso/data.h>
#else
struct arch_vdso_data {};
#endif
#define VDSO_BASES (CLOCK_TAI + 1)
#define VDSO_HRES (BIT(CLOCK_REALTIME) | \
BIT(CLOCK_MONOTONIC) | \
@ -64,6 +70,8 @@ struct vdso_timestamp {
* @tz_dsttime: type of DST correction
* @hrtimer_res: hrtimer resolution
* @__unused: unused
* @arch_data: architecture specific data (optional, defaults
* to an empty struct)
*
* vdso_data will be accessed by 64 bit and compat code at the same time
* so we should be careful before modifying this structure.
@ -97,6 +105,8 @@ struct vdso_data {
s32 tz_dsttime;
u32 hrtimer_res;
u32 __unused;
struct arch_vdso_data arch_data;
};
/*