arch/arm/include/asm/vdso/vsyscall.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 #ifndef __ASM_VDSO_VSYSCALL_H
   3 #define __ASM_VDSO_VSYSCALL_H
   4
   5 #ifndef __ASSEMBLY__
   6
   7 #include <linux/timekeeper_internal.h>
   8 #include <vdso/datapage.h>
   9 #include <asm/cacheflush.h>
  10
  11 extern struct vdso_data *vdso_data;
  12 extern bool cntvct_ok;
  13
  14 static __always_inline
  15 bool tk_is_cntvct(const struct timekeeper *tk)
  16 {
  17         if (!IS_ENABLED(CONFIG_ARM_ARCH_TIMER))
  18                 return false;
  19
  20         if (!tk->tkr_mono.clock->archdata.vdso_direct)
  21                 return false;
  22
  23         return true;
  24 }
  25
  26 /*
  27  * Update the vDSO data page to keep in sync with kernel timekeeping.
  28  */
  29 static __always_inline
  30 struct vdso_data *__arm_get_k_vdso_data(void)
  31 {
  32         return vdso_data;
  33 }
  34 #define __arch_get_k_vdso_data __arm_get_k_vdso_data
  35
  36 static __always_inline
  37 bool __arm_update_vdso_data(void)
  38 {
  39         return cntvct_ok;
  40 }
  41 #define __arch_update_vdso_data __arm_update_vdso_data
  42
  43 static __always_inline
  44 int __arm_get_clock_mode(struct timekeeper *tk)
  45 {
  46         u32 __tk_is_cntvct = tk_is_cntvct(tk);
  47
  48         return __tk_is_cntvct;
  49 }
  50 #define __arch_get_clock_mode __arm_get_clock_mode
  51
  52 static __always_inline
  53 int __arm_use_vsyscall(struct vdso_data *vdata)
  54 {
  55         return vdata[CS_HRES_COARSE].clock_mode;
  56 }
  57 #define __arch_use_vsyscall __arm_use_vsyscall
  58
  59 static __always_inline
  60 void __arm_sync_vdso_data(struct vdso_data *vdata)
  61 {
  62         flush_dcache_page(virt_to_page(vdata));
  63 }
  64 #define __arch_sync_vdso_data __arm_sync_vdso_data
  65
  66 /* The asm-generic header needs to be included after the definitions above */
  67 #include <asm-generic/vdso/vsyscall.h>
  68
  69 #endif /* !__ASSEMBLY__ */
  70
  71 #endif /* __ASM_VDSO_VSYSCALL_H */