From 8d47b8e5c74a1be600fd68bbbb4c2ecd8d4cc33c Mon Sep 17 00:00:00 2001 From: Ard Biesheuvel Date: Wed, 14 Feb 2024 13:29:00 +0100 Subject: [PATCH] arm64: head: allocate more pages for the kernel mapping In preparation for switching to an early kernel mapping routine that maps each segment according to its precise boundaries, and with the correct attributes, let's allocate some extra pages for page tables for the 4k page size configuration. This is necessary because the start and end of each segment may not be aligned to the block size, and so we'll need an extra page table at each segment boundary. Signed-off-by: Ard Biesheuvel Link: https://lore.kernel.org/r/20240214122845.2033971-59-ardb+git@google.com Signed-off-by: Catalin Marinas --- arch/arm64/include/asm/kernel-pgtable.h | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-) diff --git a/arch/arm64/include/asm/kernel-pgtable.h b/arch/arm64/include/asm/kernel-pgtable.h index 83ddb14b95a5e..0631604995eed 100644 --- a/arch/arm64/include/asm/kernel-pgtable.h +++ b/arch/arm64/include/asm/kernel-pgtable.h @@ -68,7 +68,7 @@ + EARLY_PGDS((vstart), (vend), add) /* each PGDIR needs a next level page table */ \ + EARLY_PUDS((vstart), (vend), add) /* each PUD needs a next level page table */ \ + EARLY_PMDS((vstart), (vend), add)) /* each PMD needs a next level page table */ -#define INIT_DIR_SIZE (PAGE_SIZE * EARLY_PAGES(KIMAGE_VADDR, _end, EXTRA_PAGE)) +#define INIT_DIR_SIZE (PAGE_SIZE * (EARLY_PAGES(KIMAGE_VADDR, _end, EXTRA_PAGE) + EARLY_SEGMENT_EXTRA_PAGES)) /* the initial ID map may need two extra pages if it needs to be extended */ #if VA_BITS < 48 @@ -89,6 +89,15 @@ #define SWAPPER_TABLE_SHIFT PMD_SHIFT #endif +/* The number of segments in the kernel image (text, rodata, inittext, initdata, data+bss) */ +#define KERNEL_SEGMENT_COUNT 5 + +#if SWAPPER_BLOCK_SIZE > SEGMENT_ALIGN +#define EARLY_SEGMENT_EXTRA_PAGES (KERNEL_SEGMENT_COUNT + 1) +#else +#define EARLY_SEGMENT_EXTRA_PAGES 0 +#endif + /* * Initial memory map attributes. */ -- 2.30.2