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
arm64_ioremap_prot_hook_register(ioremap_prot_hook_t hook)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
ioremap_prot(phys_addr_t phys_addr,size_t size,pgprot_t pgprot)17 void __iomem *ioremap_prot(phys_addr_t phys_addr, size_t size,
18 pgprot_t pgprot)
19 {
20 unsigned long last_addr = phys_addr + size - 1;
21
22 /* Don't allow outside PHYS_MASK */
23 if (last_addr & ~PHYS_MASK)
24 return NULL;
25
26 /* Don't allow RAM to be mapped. */
27 if (WARN_ON(pfn_is_map_memory(__phys_to_pfn(phys_addr))))
28 return NULL;
29
30 /*
31 * If a hook is registered (e.g. for confidential computing
32 * purposes), call that now and barf if it fails.
33 */
34 if (unlikely(ioremap_prot_hook) &&
35 WARN_ON(ioremap_prot_hook(phys_addr, size, &pgprot))) {
36 return NULL;
37 }
38
39 return generic_ioremap_prot(phys_addr, size, pgprot);
40 }
41 EXPORT_SYMBOL(ioremap_prot);
42
43 /*
44 * Must be called after early_fixmap_init
45 */
early_ioremap_init(void)46 void __init early_ioremap_init(void)
47 {
48 early_ioremap_setup();
49 }
50
arch_memremap_can_ram_remap(resource_size_t offset,size_t size,unsigned long flags)51 bool arch_memremap_can_ram_remap(resource_size_t offset, size_t size,
52 unsigned long flags)
53 {
54 unsigned long pfn = PHYS_PFN(offset);
55
56 return pfn_is_map_memory(pfn);
57 }
58