#include "physaddr.h"
+struct ioremap_mem_flags {
+ bool system_ram;
+ bool desc_other;
+};
+
/*
* Fix up the linear direct mapping of the kernel to avoid cache attribute
* conflicts.
return err;
}
-static int __ioremap_check_ram(unsigned long start_pfn, unsigned long nr_pages,
- void *arg)
+static bool __ioremap_check_ram(struct resource *res)
{
+ unsigned long start_pfn, stop_pfn;
unsigned long i;
- for (i = 0; i < nr_pages; ++i)
- if (pfn_valid(start_pfn + i) &&
- !PageReserved(pfn_to_page(start_pfn + i)))
- return 1;
+ if ((res->flags & IORESOURCE_SYSTEM_RAM) != IORESOURCE_SYSTEM_RAM)
+ return false;
- return 0;
+ start_pfn = (res->start + PAGE_SIZE - 1) >> PAGE_SHIFT;
+ stop_pfn = (res->end + 1) >> PAGE_SHIFT;
+ if (stop_pfn > start_pfn) {
+ for (i = 0; i < (stop_pfn - start_pfn); ++i)
+ if (pfn_valid(start_pfn + i) &&
+ !PageReserved(pfn_to_page(start_pfn + i)))
+ return true;
+ }
+
+ return false;
+}
+
+static int __ioremap_check_desc_other(struct resource *res)
+{
+ return (res->desc != IORES_DESC_NONE);
+}
+
+static int __ioremap_res_check(struct resource *res, void *arg)
+{
+ struct ioremap_mem_flags *flags = arg;
+
+ if (!flags->system_ram)
+ flags->system_ram = __ioremap_check_ram(res);
+
+ if (!flags->desc_other)
+ flags->desc_other = __ioremap_check_desc_other(res);
+
+ return flags->system_ram && flags->desc_other;
+}
+
+/*
+ * To avoid multiple resource walks, this function walks resources marked as
+ * IORESOURCE_MEM and IORESOURCE_BUSY and looking for system RAM and/or a
+ * resource described not as IORES_DESC_NONE (e.g. IORES_DESC_ACPI_TABLES).
+ */
+static void __ioremap_check_mem(resource_size_t addr, unsigned long size,
+ struct ioremap_mem_flags *flags)
+{
+ u64 start, end;
+
+ start = (u64)addr;
+ end = start + size - 1;
+ memset(flags, 0, sizeof(*flags));
+
+ walk_mem_res(start, end, flags, __ioremap_res_check);
}
/*
unsigned long size, enum page_cache_mode pcm, void *caller)
{
unsigned long offset, vaddr;
- resource_size_t pfn, last_pfn, last_addr;
+ resource_size_t last_addr;
const resource_size_t unaligned_phys_addr = phys_addr;
const unsigned long unaligned_size = size;
+ struct ioremap_mem_flags mem_flags;
struct vm_struct *area;
enum page_cache_mode new_pcm;
pgprot_t prot;
return NULL;
}
+ __ioremap_check_mem(phys_addr, size, &mem_flags);
+
/*
* Don't allow anybody to remap normal RAM that we're using..
*/
- pfn = phys_addr >> PAGE_SHIFT;
- last_pfn = last_addr >> PAGE_SHIFT;
- if (walk_system_ram_range(pfn, last_pfn - pfn + 1, NULL,
- __ioremap_check_ram) == 1) {
+ if (mem_flags.system_ram) {
WARN_ONCE(1, "ioremap on RAM at %pa - %pa\n",
&phys_addr, &last_addr);
return NULL;
pcm = new_pcm;
}
+ /*
+ * If the page being mapped is in memory and SEV is active then
+ * make sure the memory encryption attribute is enabled in the
+ * resulting mapping.
+ */
prot = PAGE_KERNEL_IO;
+ if (sev_active() && mem_flags.desc_other)
+ prot = pgprot_encrypted(prot);
+
switch (pcm) {
case _PAGE_CACHE_MODE_UC:
default:
* areas should be mapped decrypted. And since the encryption key can
* change across reboots, persistent memory should also be mapped
* decrypted.
+ *
+ * If SEV is active, that implies that BIOS/UEFI also ran encrypted so
+ * only persistent memory should be mapped decrypted.
*/
static bool memremap_should_map_decrypted(resource_size_t phys_addr,
unsigned long size)
case E820_TYPE_ACPI:
case E820_TYPE_NVS:
case E820_TYPE_UNUSABLE:
+ /* For SEV, these areas are encrypted */
+ if (sev_active())
+ break;
+ /* Fallthrough */
+
case E820_TYPE_PRAM:
return true;
default:
bool arch_memremap_can_ram_remap(resource_size_t phys_addr, unsigned long size,
unsigned long flags)
{
- if (!sme_active())
+ if (!mem_encrypt_active())
return true;
if (flags & MEMREMAP_ENC)
if (flags & MEMREMAP_DEC)
return false;
- if (memremap_is_setup_data(phys_addr, size) ||
- memremap_is_efi_data(phys_addr, size) ||
- memremap_should_map_decrypted(phys_addr, size))
- return false;
+ if (sme_active()) {
+ if (memremap_is_setup_data(phys_addr, size) ||
+ memremap_is_efi_data(phys_addr, size))
+ return false;
+ }
- return true;
+ return !memremap_should_map_decrypted(phys_addr, size);
}
/*
unsigned long size,
pgprot_t prot)
{
- if (!sme_active())
+ bool encrypted_prot;
+
+ if (!mem_encrypt_active())
return prot;
- if (early_memremap_is_setup_data(phys_addr, size) ||
- memremap_is_efi_data(phys_addr, size) ||
- memremap_should_map_decrypted(phys_addr, size))
- prot = pgprot_decrypted(prot);
- else
- prot = pgprot_encrypted(prot);
+ encrypted_prot = true;
+
+ if (sme_active()) {
+ if (early_memremap_is_setup_data(phys_addr, size) ||
+ memremap_is_efi_data(phys_addr, size))
+ encrypted_prot = false;
+ }
+
+ if (encrypted_prot && memremap_should_map_decrypted(phys_addr, size))
+ encrypted_prot = false;
- return prot;
+ return encrypted_prot ? pgprot_encrypted(prot)
+ : pgprot_decrypted(prot);
}
bool phys_mem_access_encrypted(unsigned long phys_addr, unsigned long size)
git.samba.org / sfrench / cifs-2.6.git / blobdiff