diff options
Diffstat (limited to 'arch/arm64/mm/ioremap.c')
| -rw-r--r-- | arch/arm64/mm/ioremap.c | 23 |
1 files changed, 22 insertions, 1 deletions
diff --git a/arch/arm64/mm/ioremap.c b/arch/arm64/mm/ioremap.c index 269f2f63ab7d..6cc0b7e7eb03 100644 --- a/arch/arm64/mm/ioremap.c +++ b/arch/arm64/mm/ioremap.c @@ -3,10 +3,22 @@ #include <linux/mm.h> #include <linux/io.h> +static ioremap_prot_hook_t ioremap_prot_hook; + +int arm64_ioremap_prot_hook_register(ioremap_prot_hook_t hook) +{ + if (WARN_ON(ioremap_prot_hook)) + return -EBUSY; + + ioremap_prot_hook = hook; + return 0; +} + void __iomem *ioremap_prot(phys_addr_t phys_addr, size_t size, unsigned long prot) { unsigned long last_addr = phys_addr + size - 1; + pgprot_t pgprot = __pgprot(prot); /* Don't allow outside PHYS_MASK */ if (last_addr & ~PHYS_MASK) @@ -16,7 +28,16 @@ void __iomem *ioremap_prot(phys_addr_t phys_addr, size_t size, if (WARN_ON(pfn_is_map_memory(__phys_to_pfn(phys_addr)))) return NULL; - return generic_ioremap_prot(phys_addr, size, __pgprot(prot)); + /* + * If a hook is registered (e.g. for confidential computing + * purposes), call that now and barf if it fails. + */ + if (unlikely(ioremap_prot_hook) && + WARN_ON(ioremap_prot_hook(phys_addr, size, &pgprot))) { + return NULL; + } + + return generic_ioremap_prot(phys_addr, size, pgprot); } EXPORT_SYMBOL(ioremap_prot); |