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author | Ingo Molnar <mingo@kernel.org> | 2015-03-03 07:48:50 +0100 |
---|---|---|
committer | Matt Fleming <matt.fleming@intel.com> | 2015-04-01 12:46:22 +0100 |
commit | 744937b0b12a669f298949c4a810794c59fead98 (patch) | |
tree | d7d4082f50f1b56a6844012aaf5ff95690686aa1 /arch/x86/platform/efi/efi_32.c | |
parent | 23a0d4e8fa6d3a1d7fb819f79bcc0a3739c30ba9 (diff) | |
download | op-kernel-dev-744937b0b12a669f298949c4a810794c59fead98.zip op-kernel-dev-744937b0b12a669f298949c4a810794c59fead98.tar.gz |
efi: Clean up the efi_call_phys_[prolog|epilog]() save/restore interaction
Currently x86-64 efi_call_phys_prolog() saves into a global variable (save_pgd),
and efi_call_phys_epilog() restores the kernel pagetables from that global
variable.
Change this to a cleaner save/restore pattern where the saving function returns
the saved object and the restore function restores that.
Apply the same concept to the 32-bit code as well.
Plus this approach, as an added bonus, allows us to express the
!efi_enabled(EFI_OLD_MEMMAP) situation in a clean fashion as well,
via a 'NULL' return value.
Cc: Tapasweni Pathak <tapaswenipathak@gmail.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Diffstat (limited to 'arch/x86/platform/efi/efi_32.c')
-rw-r--r-- | arch/x86/platform/efi/efi_32.c | 11 |
1 files changed, 8 insertions, 3 deletions
diff --git a/arch/x86/platform/efi/efi_32.c b/arch/x86/platform/efi/efi_32.c index abecc6e..ed5b673 100644 --- a/arch/x86/platform/efi/efi_32.c +++ b/arch/x86/platform/efi/efi_32.c @@ -56,19 +56,24 @@ void __init efi_map_region(efi_memory_desc_t *md) void __init efi_map_region_fixed(efi_memory_desc_t *md) {} void __init parse_efi_setup(u64 phys_addr, u32 data_len) {} -void __init efi_call_phys_prolog(void) +pgd_t * __init efi_call_phys_prolog(void) { struct desc_ptr gdt_descr; + pgd_t *save_pgd; + /* Current pgd is swapper_pg_dir, we'll restore it later: */ + save_pgd = swapper_pg_dir; load_cr3(initial_page_table); __flush_tlb_all(); gdt_descr.address = __pa(get_cpu_gdt_table(0)); gdt_descr.size = GDT_SIZE - 1; load_gdt(&gdt_descr); + + return save_pgd; } -void __init efi_call_phys_epilog(void) +void __init efi_call_phys_epilog(pgd_t *save_pgd) { struct desc_ptr gdt_descr; @@ -76,7 +81,7 @@ void __init efi_call_phys_epilog(void) gdt_descr.size = GDT_SIZE - 1; load_gdt(&gdt_descr); - load_cr3(swapper_pg_dir); + load_cr3(save_pgd); __flush_tlb_all(); } |