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Date: Sat, 18 Jan 2014 12:48:18 +0100
From: Borislav Petkov <bp@...en8.de>
To: Linux EFI <linux-efi@...r.kernel.org>
Cc: LKML <linux-kernel@...r.kernel.org>, Borislav Petkov <bp@...e.de>,
Matt Fleming <matt@...sole-pimps.org>,
Matthew Garrett <mjg59@...f.ucam.org>,
"H. Peter Anvin" <hpa@...or.com>, Toshi Kani <toshi.kani@...com>
Subject: [PATCH 5/5] efi: Split efi_enter_virtual_mode
From: Borislav Petkov <bp@...e.de>
... into a kexec flavor for better code readability and simplicity. The
original one was getting ugly with ifdeffery.
Signed-off-by: Borislav Petkov <bp@...e.de>
Tested-by: Toshi Kani <toshi.kani@...com>
---
arch/x86/platform/efi/efi.c | 148 +++++++++++++++++++++++++++++---------------
include/linux/efi.h | 1 +
2 files changed, 99 insertions(+), 50 deletions(-)
diff --git a/arch/x86/platform/efi/efi.c b/arch/x86/platform/efi/efi.c
index b79a85c8a6aa..bcc3e5117fd7 100644
--- a/arch/x86/platform/efi/efi.c
+++ b/arch/x86/platform/efi/efi.c
@@ -891,8 +891,9 @@ static void __init get_systab_virt_addr(efi_memory_desc_t *md)
}
}
-static int __init save_runtime_map(void)
+static void __init save_runtime_map(void)
{
+#ifdef CONFIG_KEXEC
efi_memory_desc_t *md;
void *tmp, *p, *q = NULL;
int count = 0;
@@ -914,28 +915,12 @@ static int __init save_runtime_map(void)
}
efi_runtime_map_setup(q, count, memmap.desc_size);
+ return;
- return 0;
out:
kfree(q);
- return -ENOMEM;
-}
-
-/*
- * Map efi regions which were passed via setup_data. The virt_addr is a fixed
- * addr which was used in first kernel of a kexec boot.
- */
-static void __init efi_map_regions_fixed(void)
-{
- void *p;
- efi_memory_desc_t *md;
-
- for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
- md = p;
- efi_map_region_fixed(md); /* FIXME: add error handling */
- get_systab_virt_addr(md);
- }
-
+ pr_err("Error saving runtime map, efi runtime on kexec non-functional!!\n");
+#endif
}
static void *realloc_pages(void *old_memmap, int old_shift)
@@ -1001,6 +986,72 @@ static void * __init efi_map_regions(int *count, int *pg_shift)
return new_memmap;
}
+void __init kexec_enter_virtual_mode(void)
+{
+#ifdef CONFIG_KEXEC
+ efi_memory_desc_t *md;
+ void *p;
+
+ 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;
+ }
+
+ /*
+ * Map efi regions which were passed via setup_data. The virt_addr is a
+ * fixed addr which was used in first kernel of a kexec boot.
+ */
+ for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
+ md = p;
+ efi_map_region_fixed(md); /* FIXME: add error handling */
+ get_systab_virt_addr(md);
+ }
+
+ save_runtime_map();
+
+ BUG_ON(!efi.systab);
+
+ efi_sync_low_kernel_mappings();
+
+ /*
+ * Now that EFI is in virtual mode, update the function
+ * pointers in the runtime service table to the new virtual addresses.
+ *
+ * Call EFI services through wrapper functions.
+ */
+ efi.runtime_version = efi_systab.hdr.revision;
+ efi.get_time = virt_efi_get_time;
+ efi.set_time = virt_efi_set_time;
+ efi.get_wakeup_time = virt_efi_get_wakeup_time;
+ efi.set_wakeup_time = virt_efi_set_wakeup_time;
+ efi.get_variable = virt_efi_get_variable;
+ efi.get_next_variable = virt_efi_get_next_variable;
+ efi.set_variable = virt_efi_set_variable;
+ efi.get_next_high_mono_count = virt_efi_get_next_high_mono_count;
+ efi.reset_system = virt_efi_reset_system;
+ efi.set_virtual_address_map = NULL;
+ efi.query_variable_info = virt_efi_query_variable_info;
+ efi.update_capsule = virt_efi_update_capsule;
+ efi.query_capsule_caps = virt_efi_query_capsule_caps;
+
+ if (efi_enabled(EFI_OLD_MEMMAP) && (__supported_pte_mask & _PAGE_NX))
+ runtime_code_page_mkexec();
+
+ /* clean DUMMY object */
+ efi.set_variable(efi_dummy_name, &EFI_DUMMY_GUID,
+ EFI_VARIABLE_NON_VOLATILE |
+ EFI_VARIABLE_BOOTSERVICE_ACCESS |
+ EFI_VARIABLE_RUNTIME_ACCESS,
+ 0, NULL);
+#endif
+}
+
/*
* This function will switch the EFI runtime services to virtual mode.
* Essentially, we look through the EFI memmap and map every region that
@@ -1020,11 +1071,12 @@ static void * __init efi_map_regions(int *count, int *pg_shift)
*
* Specially for kexec boot, efi runtime maps in previous kernel should
* be passed in via setup_data. In that case runtime ranges will be mapped
- * to the same virtual addresses as the first kernel.
+ * to the same virtual addresses as the first kernel, see
+ * kexec_enter_virtual_mode().
*/
-void __init efi_enter_virtual_mode(void)
+static void __init __efi_enter_virtual_mode(void)
{
- int err, count = 0, pg_shift = 0;
+ int count = 0, pg_shift = 0;
void *new_memmap = NULL;
efi_status_t status;
@@ -1039,43 +1091,33 @@ void __init efi_enter_virtual_mode(void)
return;
}
- if (efi_setup) {
- efi_map_regions_fixed();
- } else {
- efi_merge_regions();
- new_memmap = efi_map_regions(&count, &pg_shift);
- if (!new_memmap) {
- pr_err("Error reallocating memory, EFI runtime non-functional!\n");
- return;
- }
-
- err = save_runtime_map();
- if (err)
- pr_err("Error saving runtime map, efi runtime on kexec non-functional!!\n");
+ efi_merge_regions();
+ new_memmap = efi_map_regions(&count, &pg_shift);
+ if (!new_memmap) {
+ pr_err("Error reallocating memory, EFI runtime non-functional!\n");
+ return;
}
+ save_runtime_map();
+
BUG_ON(!efi.systab);
- if (!efi_setup) {
- if (efi_setup_page_tables(__pa(new_memmap), 1 << pg_shift))
- return;
- }
+ if (efi_setup_page_tables(__pa(new_memmap), 1 << pg_shift))
+ return;
efi_sync_low_kernel_mappings();
efi_dump_pagetable();
- if (!efi_setup) {
- status = phys_efi_set_virtual_address_map(
+ status = phys_efi_set_virtual_address_map(
memmap.desc_size * count,
memmap.desc_size,
memmap.desc_version,
(efi_memory_desc_t *)__pa(new_memmap));
- if (status != EFI_SUCCESS) {
- pr_alert("Unable to switch EFI into virtual mode (status=%lx)!\n",
- status);
- panic("EFI call to SetVirtualAddressMap() failed!");
- }
+ if (status != EFI_SUCCESS) {
+ pr_alert("Unable to switch EFI into virtual mode (status=%lx)!\n",
+ status);
+ panic("EFI call to SetVirtualAddressMap() failed!");
}
/*
@@ -1102,7 +1144,6 @@ void __init efi_enter_virtual_mode(void)
if (efi_enabled(EFI_OLD_MEMMAP) && (__supported_pte_mask & _PAGE_NX))
runtime_code_page_mkexec();
-
/*
* We mapped the descriptor array into the EFI pagetable above but we're
* not unmapping it here. Here's why:
@@ -1129,8 +1170,7 @@ void __init efi_enter_virtual_mode(void)
*
* efi_cleanup_page_tables(__pa(new_memmap), 1 << pg_shift);
*/
- if (!efi_setup)
- free_pages((unsigned long)new_memmap, pg_shift);
+ free_pages((unsigned long)new_memmap, pg_shift);
/* clean DUMMY object */
efi.set_variable(efi_dummy_name, &EFI_DUMMY_GUID,
@@ -1140,6 +1180,14 @@ void __init efi_enter_virtual_mode(void)
0, NULL);
}
+void __init efi_enter_virtual_mode(void)
+{
+ if (efi_setup)
+ kexec_enter_virtual_mode();
+ else
+ __efi_enter_virtual_mode();
+}
+
/*
* Convenience functions to obtain memory types and attributes
*/
diff --git a/include/linux/efi.h b/include/linux/efi.h
index 0a819e7a60c9..44ea66ce41e0 100644
--- a/include/linux/efi.h
+++ b/include/linux/efi.h
@@ -594,6 +594,7 @@ extern void efi_map_pal_code (void);
extern void efi_memmap_walk (efi_freemem_callback_t callback, void *arg);
extern void efi_gettimeofday (struct timespec *ts);
extern void efi_enter_virtual_mode (void); /* switch EFI to virtual mode, if possible */
+extern void kexec_enter_virtual_mode(void);
#ifdef CONFIG_X86
extern void efi_late_init(void);
extern void efi_free_boot_services(void);
--
1.8.5.2.192.g7794a68
--
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