1 // SPDX-License-Identifier: GPL-2.0-only 2 3 #include <linux/mm.h> 4 #include <linux/io.h> 5 6 static ioremap_prot_hook_t ioremap_prot_hook; 7 8 int arm64_ioremap_prot_hook_register(ioremap_prot_hook_t hook) 9 { 10 if (WARN_ON(ioremap_prot_hook)) 11 return -EBUSY; 12 13 ioremap_prot_hook = hook; 14 return 0; 15 } 16 17 void __iomem *ioremap_prot(phys_addr_t phys_addr, size_t size, 18 unsigned long prot) 19 { 20 unsigned long last_addr = phys_addr + size - 1; 21 pgprot_t pgprot = __pgprot(prot); 22 23 /* Don't allow outside PHYS_MASK */ 24 if (last_addr & ~PHYS_MASK) 25 return NULL; 26 27 /* Don't allow RAM to be mapped. */ 28 if (WARN_ON(pfn_is_map_memory(__phys_to_pfn(phys_addr)))) 29 return NULL; 30 31 /* 32 * If a hook is registered (e.g. for confidential computing 33 * purposes), call that now and barf if it fails. 34 */ 35 if (unlikely(ioremap_prot_hook) && 36 WARN_ON(ioremap_prot_hook(phys_addr, size, &pgprot))) { 37 return NULL; 38 } 39 40 return generic_ioremap_prot(phys_addr, size, pgprot); 41 } 42 EXPORT_SYMBOL(ioremap_prot); 43 44 /* 45 * Must be called after early_fixmap_init 46 */ 47 void __init early_ioremap_init(void) 48 { 49 early_ioremap_setup(); 50 } 51 52 bool arch_memremap_can_ram_remap(resource_size_t offset, size_t size, 53 unsigned long flags) 54 { 55 unsigned long pfn = PHYS_PFN(offset); 56 57 return pfn_is_map_memory(pfn); 58 } 59