From a9ee679b1f8c3803490ed2eeffb688aaee56583f Mon Sep 17 00:00:00 2001 From: Michael Roth Date: Thu, 24 Feb 2022 10:56:16 -0600 Subject: [PATCH] x86/compressed: Export and rename add_identity_map() SEV-specific code will need to add some additional mappings, but doing this within ident_map_64.c requires some SEV-specific helpers to be exported and some SEV-specific struct definitions to be pulled into ident_map_64.c. Instead, export add_identity_map() so SEV-specific (and other subsystem-specific) code can be better contained outside of ident_map_64.c. While at it, rename the function to kernel_add_identity_map(), similar to the kernel_ident_mapping_init() function it relies upon. No functional changes. Suggested-by: Borislav Petkov Signed-off-by: Michael Roth Signed-off-by: Borislav Petkov Link: https://lore.kernel.org/r/20220307213356.2797205-37-brijesh.singh@amd.com --- arch/x86/boot/compressed/ident_map_64.c | 18 +++++++++--------- arch/x86/boot/compressed/misc.h | 1 + 2 files changed, 10 insertions(+), 9 deletions(-) diff --git a/arch/x86/boot/compressed/ident_map_64.c b/arch/x86/boot/compressed/ident_map_64.c index 613367e7e09e..99348ee7999b 100644 --- a/arch/x86/boot/compressed/ident_map_64.c +++ b/arch/x86/boot/compressed/ident_map_64.c @@ -90,7 +90,7 @@ static struct x86_mapping_info mapping_info; /* * Adds the specified range to the identity mappings. */ -static void add_identity_map(unsigned long start, unsigned long end) +void kernel_add_identity_map(unsigned long start, unsigned long end) { int ret; @@ -157,11 +157,11 @@ void initialize_identity_maps(void *rmode) * explicitly here in case the compressed kernel does not touch them, * or does not touch all the pages covering them. */ - add_identity_map((unsigned long)_head, (unsigned long)_end); + kernel_add_identity_map((unsigned long)_head, (unsigned long)_end); boot_params = rmode; - add_identity_map((unsigned long)boot_params, (unsigned long)(boot_params + 1)); + kernel_add_identity_map((unsigned long)boot_params, (unsigned long)(boot_params + 1)); cmdline = get_cmd_line_ptr(); - add_identity_map(cmdline, cmdline + COMMAND_LINE_SIZE); + kernel_add_identity_map(cmdline, cmdline + COMMAND_LINE_SIZE); /* Load the new page-table. */ sev_verify_cbit(top_level_pgt); @@ -246,10 +246,10 @@ static int set_clr_page_flags(struct x86_mapping_info *info, * It should already exist, but keep things generic. * * To map the page just read from it and fault it in if there is no - * mapping yet. add_identity_map() can't be called here because that - * would unconditionally map the address on PMD level, destroying any - * PTE-level mappings that might already exist. Use assembly here so - * the access won't be optimized away. + * mapping yet. kernel_add_identity_map() can't be called here because + * that would unconditionally map the address on PMD level, destroying + * any PTE-level mappings that might already exist. Use assembly here + * so the access won't be optimized away. */ asm volatile("mov %[address], %%r9" :: [address] "g" (*(unsigned long *)address) @@ -363,5 +363,5 @@ void do_boot_page_fault(struct pt_regs *regs, unsigned long error_code) * Error code is sane - now identity map the 2M region around * the faulting address. */ - add_identity_map(address, end); + kernel_add_identity_map(address, end); } diff --git a/arch/x86/boot/compressed/misc.h b/arch/x86/boot/compressed/misc.h index ba538af37e90..aae2722c6e9a 100644 --- a/arch/x86/boot/compressed/misc.h +++ b/arch/x86/boot/compressed/misc.h @@ -156,6 +156,7 @@ static inline int count_immovable_mem_regions(void) { return 0; } #ifdef CONFIG_X86_5LEVEL extern unsigned int __pgtable_l5_enabled, pgdir_shift, ptrs_per_p4d; #endif +extern void kernel_add_identity_map(unsigned long start, unsigned long end); /* Used by PAGE_KERN* macros: */ extern pteval_t __default_kernel_pte_mask;