@@ -38,8 +38,10 @@
*/
#define PCI_IO_SIZE SZ_16M
+#define KIMAGE_OFFSET SZ_64M
+
/*
- * PAGE_OFFSET - the virtual address of the start of the kernel image (top
+ * PAGE_OFFSET - the virtual address of the base of the linear mapping (top
* (VA_BITS - 1))
* VA_BITS - the maximum number of bits for virtual addresses.
* TASK_SIZE - the maximum size of a user space task.
@@ -49,7 +51,8 @@
*/
#define VA_BITS (CONFIG_ARM64_VA_BITS)
#define PAGE_OFFSET (UL(0xffffffffffffffff) << (VA_BITS - 1))
-#define MODULES_END (PAGE_OFFSET)
+#define KIMAGE_VADDR (PAGE_OFFSET - KIMAGE_OFFSET)
+#define MODULES_END KIMAGE_VADDR
#define MODULES_VADDR (MODULES_END - SZ_64M)
#define PCI_IO_END (MODULES_VADDR - SZ_2M)
#define PCI_IO_START (PCI_IO_END - PCI_IO_SIZE)
@@ -77,7 +80,11 @@
* private definitions which should NOT be used outside memory.h
* files. Use virt_to_phys/phys_to_virt/__pa/__va instead.
*/
-#define __virt_to_phys(x) (((phys_addr_t)(x) - PAGE_OFFSET + PHYS_OFFSET))
+#define __virt_to_phys(x) ({ \
+ long __x = (long)(x) - PAGE_OFFSET; \
+ __x >= 0 ? (phys_addr_t)(__x + PHYS_OFFSET) : \
+ (phys_addr_t)(__x + PHYS_OFFSET + image_offset); })
+
#define __phys_to_virt(x) ((unsigned long)((x) - PHYS_OFFSET + PAGE_OFFSET))
/*
@@ -113,6 +120,8 @@ extern phys_addr_t memstart_addr;
/* PHYS_OFFSET - the physical address of the start of memory. */
#define PHYS_OFFSET ({ memstart_addr; })
+extern u64 image_offset;
+
/*
* PFNs are used to describe any physical page; this means
* PFN 0 == physical address 0.
@@ -36,8 +36,6 @@
#include <asm/page.h>
#include <asm/virt.h>
-#define __PHYS_OFFSET (KERNEL_START - TEXT_OFFSET)
-
#if (TEXT_OFFSET & 0xfff) != 0
#error TEXT_OFFSET must be at least 4KB aligned
#elif (PAGE_OFFSET & 0x1fffff) != 0
@@ -58,6 +56,8 @@
#define KERNEL_START _text
#define KERNEL_END _end
+#define KERNEL_BASE (KERNEL_START - TEXT_OFFSET)
+
/*
* Initial memory map attributes.
@@ -235,7 +235,7 @@ section_table:
ENTRY(stext)
bl preserve_boot_args
bl el2_setup // Drop to EL1, w20=cpu_boot_mode
- adrp x24, __PHYS_OFFSET
+ adrp x24, KERNEL_BASE
bl set_cpu_boot_mode_flag
bl __create_page_tables // x25=TTBR0, x26=TTBR1
/*
@@ -411,7 +411,7 @@ __create_page_tables:
* Map the kernel image (starting with PHYS_OFFSET).
*/
mov x0, x26 // swapper_pg_dir
- mov x5, #PAGE_OFFSET
+ ldr x5, =KERNEL_BASE
create_pgd_entry x0, x5, x3, x6
ldr x6, =KERNEL_END // __va(KERNEL_END)
mov x3, x24 // phys offset
@@ -84,7 +84,7 @@ SECTIONS
*(.discard.*)
}
- . = PAGE_OFFSET + TEXT_OFFSET;
+ . = KIMAGE_VADDR + TEXT_OFFSET;
.head.text : {
_text = .;
@@ -195,4 +195,4 @@ ASSERT(SIZEOF(.pgdir) < ALIGNOF(.pgdir), ".pgdir size exceeds its alignment")
/*
* If padding is applied before .head.text, virt<->phys conversions will fail.
*/
-ASSERT(_text == (PAGE_OFFSET + TEXT_OFFSET), "HEAD is misaligned")
+ASSERT(_text == (KIMAGE_VADDR + TEXT_OFFSET), "HEAD is misaligned")
@@ -49,6 +49,8 @@ u64 idmap_t0sz = TCR_T0SZ(VA_BITS);
struct page *empty_zero_page;
EXPORT_SYMBOL(empty_zero_page);
+u64 image_offset __read_mostly = KIMAGE_OFFSET;
+
pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
unsigned long size, pgprot_t vma_prot)
{
This moves the primary mapping of the kernel Image out of the linear region. This is a preparatory step towards allowing the kernel Image to reside anywhere in physical memory without affecting the ability to map all of it efficiently. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> --- arch/arm64/include/asm/memory.h | 15 ++++++++++++--- arch/arm64/kernel/head.S | 8 ++++---- arch/arm64/kernel/vmlinux.lds.S | 4 ++-- arch/arm64/mm/mmu.c | 2 ++ 4 files changed, 20 insertions(+), 9 deletions(-)