Re: [patch 3/6] Cleanup efi_enter_virtual_mode function

From: Dave Young
Date: Mon Oct 28 2013 - 06:11:08 EST


On 10/28/13 at 11:04am, Borislav Petkov wrote:
> On Mon, Oct 28, 2013 at 05:51:17PM +0800, Dave Young wrote:
> > It does have a warning, but it applied successfully, no idea though:
> > patches/02-efi-enter-virtual-mode-cleanup.patch
> > Applying: Cleanup efi_enter_virtual_mode function
> > /home/dave/git/efi/.git/rebase-apply/patch:42: space before tab in indent.
> > efi_memory_desc_t *md, *prev_md = NULL;
> > warning: 1 line adds whitespace errors.
>
> Hmm, ok, can you upload the patches somewhere so that I can pull them?

Sorry, I have not any public git account. Attached the patch I applied with git

>
> Thanks.
>
> --
> Regards/Gruss,
> Boris.
>
> Sent from a fat crate under my desk. Formatting is fine.
> --
From: Dave Young <dyoung@xxxxxxxxxx>
Cleanup efi_enter_virtual_mode function

Add two small functions:
efi_merge_regions and efi_map_regions, efi_enter_virtual_mode
calls them instead of embedding two long for loop.

Signed-off-by: Dave Young <dyoung@xxxxxxxxxx>
---
arch/x86/platform/efi/efi.c | 83 +++++++++++++++++++++++++++-----------------
1 file changed, 52 insertions(+), 31 deletions(-)

--- efi.orig/arch/x86/platform/efi/efi.c
+++ efi/arch/x86/platform/efi/efi.c
@@ -789,35 +789,13 @@ void __init old_map_region(efi_memory_de
pr_err("ioremap of 0x%llX failed!\n",
(unsigned long long)md->phys_addr);
}
-/*
- * This function will switch the EFI runtime services to virtual mode.
- * Essentially, look through the EFI memmap and map every region that
- * has the runtime attribute bit set in its memory descriptor and update
- * that memory descriptor with the virtual address obtained from ioremap().
- * This enables the runtime services to be called without having to
- * thunk back into physical mode for every invocation.
- */
-void __init efi_enter_virtual_mode(void)
-{
- efi_memory_desc_t *md, *prev_md = NULL;
- void *p, *new_memmap = NULL;
- unsigned long size;
- efi_status_t status;
- u64 end, systab;
- int count = 0;

- efi.systab = NULL;
-
- /*
- * We don't do virtual mode, since we don't do runtime services, on
- * non-native EFI
- */
- if (!efi_is_native()) {
- efi_unmap_memmap();
- return;
- }
+/* Merge contiguous regions of the same type and attribute */
+static void efi_merge_regions(void)
+{
+ void *p;
+ efi_memory_desc_t *md, *prev_md = NULL;

- /* Merge contiguous regions of the same type and attribute */
for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
u64 prev_size;
md = p;
@@ -844,6 +822,19 @@ void __init efi_enter_virtual_mode(void)
prev_md = md;

}
+}
+
+/*
+ * Map efi memory ranges for runtime serivce
+ * Return the new memmap with updated virtual addrresses.
+ */
+void efi_map_regions(void **new_memmap, int *count)
+{
+ efi_memory_desc_t *md, *prev_md = NULL;
+ void *p;
+ unsigned long size;
+ efi_status_t status;
+ u64 end, systab;

for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
md = p;
@@ -862,14 +853,44 @@ void __init efi_enter_virtual_mode(void)
systab += md->virt_addr - md->phys_addr;
efi.systab = (efi_system_table_t *) (unsigned long) systab;
}
- new_memmap = krealloc(new_memmap,
- (count + 1) * memmap.desc_size,
+ *new_memmap = krealloc(*new_memmap,
+ (*count + 1) * memmap.desc_size,
GFP_KERNEL);
- memcpy(new_memmap + (count * memmap.desc_size), md,
+ memcpy(*new_memmap + (*count * memmap.desc_size), md,
memmap.desc_size);
- count++;
+ (*count)++;
+ }
+}
+
+/*
+ * This function will switch the EFI runtime services to virtual mode.
+ * Essentially, look through the EFI memmap and map every region that
+ * has the runtime attribute bit set in its memory descriptor and update
+ * that memory descriptor with the virtual address obtained from ioremap().
+ * This enables the runtime services to be called without having to
+ * thunk back into physical mode for every invocation.
+ */
+void __init efi_enter_virtual_mode(void)
+{
+ efi_status_t status;
+ void *p, *new_memmap = NULL;
+ int count = 0;
+
+ efi.systab = NULL;
+
+ /*
+ * We don't do virtual mode, since we don't do runtime services, on
+ * non-native EFI
+ */
+ if (!efi_is_native()) {
+ efi_unmap_memmap();
+ return;
}

+ efi_merge_regions();
+
+ efi_map_regions(&new_memmap, &count);
+
#ifdef CONFIG_X86_64
efi_scratch.efi_pgt = (pgd_t *)(unsigned long)real_mode_header->trampoline_pgd;