diff options
| author | Thomas Weißschuh <thomas.weissschuh@linutronix.de> | 2025-02-04 13:05:39 +0100 |
|---|---|---|
| committer | Thomas Gleixner <tglx@linutronix.de> | 2025-02-21 09:54:01 +0100 |
| commit | 365841e1557ace6e8b4d5ba06a6cf53f699bc684 (patch) | |
| tree | e224d903a601777f65478c93712aaade86c362ee /lib/vdso | |
| parent | 51d6ca373f459fa6c91743e14ae69854d844aa38 (diff) | |
| download | linux-365841e1557ace6e8b4d5ba06a6cf53f699bc684.tar.gz linux-365841e1557ace6e8b4d5ba06a6cf53f699bc684.tar.bz2 linux-365841e1557ace6e8b4d5ba06a6cf53f699bc684.zip | |
vdso: Add generic architecture-specific data storage
Some architectures need to expose architecture-specific data to the vDSO.
Enable the generic vDSO storage mechanism to both store and map this
data. Some architectures require more than a single page, like LoongArch,
so prepare for that usecase, too.
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/all/20250204-vdso-store-rng-v3-7-13a4669dfc8c@linutronix.de
Diffstat (limited to 'lib/vdso')
| -rw-r--r-- | lib/vdso/datastore.c | 14 |
1 files changed, 14 insertions, 0 deletions
diff --git a/lib/vdso/datastore.c b/lib/vdso/datastore.c index 9260b00dc852..0959d62d7858 100644 --- a/lib/vdso/datastore.c +++ b/lib/vdso/datastore.c @@ -26,6 +26,14 @@ struct vdso_rng_data *vdso_k_rng_data = &vdso_rng_data_store.data; static_assert(sizeof(vdso_rng_data_store) == PAGE_SIZE); #endif /* CONFIG_VDSO_GETRANDOM */ +#ifdef CONFIG_ARCH_HAS_VDSO_ARCH_DATA +static union { + struct vdso_arch_data data; + u8 page[VDSO_ARCH_DATA_SIZE]; +} vdso_arch_data_store __page_aligned_data; +struct vdso_arch_data *vdso_k_arch_data = &vdso_arch_data_store.data; +#endif /* CONFIG_ARCH_HAS_VDSO_ARCH_DATA */ + static vm_fault_t vvar_fault(const struct vm_special_mapping *sm, struct vm_area_struct *vma, struct vm_fault *vmf) { @@ -67,6 +75,12 @@ static vm_fault_t vvar_fault(const struct vm_special_mapping *sm, return VM_FAULT_SIGBUS; pfn = __phys_to_pfn(__pa_symbol(vdso_k_rng_data)); break; + case VDSO_ARCH_PAGES_START ... VDSO_ARCH_PAGES_END: + if (!IS_ENABLED(CONFIG_ARCH_HAS_VDSO_ARCH_DATA)) + return VM_FAULT_SIGBUS; + pfn = __phys_to_pfn(__pa_symbol(vdso_k_arch_data)) + + vmf->pgoff - VDSO_ARCH_PAGES_START; + break; default: return VM_FAULT_SIGBUS; } |