efi/runtime-map: Use efi.memmap directly instead of a copy

Now that efi.memmap is available all of the time there's no need to
allocate and build a separate copy of the EFI memory map.

Furthermore, efi.memmap contains boot services regions but only those
regions that have been reserved via efi_mem_reserve(). Using
efi.memmap allows us to pass boot services across kexec reboot so that
the ESRT and BGRT drivers will now work.

Tested-by: Dave Young <dyoung@redhat.com> [kexec/kdump]
Tested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> [arm]
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Leif Lindholm <leif.lindholm@linaro.org>
Cc: Peter Jones <pjones@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>

diff --git a/arch/x86/platform/efi/efi.c b/arch/x86/platform/efi/efi.c
index 33996987ac7025096e0b0d0334714a58cfde0774..342cebd1e17ca3fa3571d6069d60175d94a81b05 100644 (file)
--- a/arch/x86/platform/efi/efi.c
+++ b/arch/x86/platform/efi/efi.c
@@ -592,42 +592,6 @@ static void __init get_systab_virt_addr(efi_memory_desc_t *md)
        }
 }
 
-static void __init save_runtime_map(void)
-{
-#ifdef CONFIG_KEXEC_CORE
-       unsigned long desc_size;
-       efi_memory_desc_t *md;
-       void *tmp, *q = NULL;
-       int count = 0;
-
-       if (efi_enabled(EFI_OLD_MEMMAP))
-               return;
-
-       desc_size = efi.memmap.desc_size;
-
-       for_each_efi_memory_desc(md) {
-               if (!(md->attribute & EFI_MEMORY_RUNTIME) ||
-                   (md->type == EFI_BOOT_SERVICES_CODE) ||
-                   (md->type == EFI_BOOT_SERVICES_DATA))
-                       continue;
-               tmp = krealloc(q, (count + 1) * desc_size, GFP_KERNEL);
-               if (!tmp)
-                       goto out;
-               q = tmp;
-
-               memcpy(q + count * desc_size, md, desc_size);
-               count++;
-       }
-
-       efi_runtime_map_setup(q, count, desc_size);
-       return;
-
-out:
-       kfree(q);
-       pr_err("Error saving runtime map, efi runtime on kexec non-functional!!\n");
-#endif
-}
-
 static void *realloc_pages(void *old_memmap, int old_shift)
 {
        void *ret;
@@ -840,8 +804,6 @@ static void __init kexec_enter_virtual_mode(void)
                return;
        }
 
-       save_runtime_map();
-
        BUG_ON(!efi.systab);
 
        num_pages = ALIGN(efi.memmap.nr_map * efi.memmap.desc_size, PAGE_SIZE);
@@ -934,8 +896,6 @@ static void __init __efi_enter_virtual_mode(void)
                return;
        }
 
-       save_runtime_map();
-
        BUG_ON(!efi.systab);
 
        if (efi_setup_page_tables(pa, 1 << pg_shift)) {

diff --git a/drivers/firmware/efi/runtime-map.c b/drivers/firmware/efi/runtime-map.c
index 5c55227a34c8fd8ba0b95a6babfb28e4726da8fe..8e64b77aeac95e43c0e0571694f42bbe6c8ba73f 100644 (file)
--- a/drivers/firmware/efi/runtime-map.c
+++ b/drivers/firmware/efi/runtime-map.c
@@ -14,10 +14,6 @@
 
 #include <asm/setup.h>
 
-static void *efi_runtime_map;
-static int nr_efi_runtime_map;
-static u32 efi_memdesc_size;
-
 struct efi_runtime_map_entry {
        efi_memory_desc_t md;
        struct kobject kobj;   /* kobject for each entry */
@@ -106,7 +102,8 @@ static struct kobj_type __refdata map_ktype = {
 static struct kset *map_kset;
 
 static struct efi_runtime_map_entry *
-add_sysfs_runtime_map_entry(struct kobject *kobj, int nr)
+add_sysfs_runtime_map_entry(struct kobject *kobj, int nr,
+                           efi_memory_desc_t *md)
 {
        int ret;
        struct efi_runtime_map_entry *entry;
@@ -124,8 +121,7 @@ add_sysfs_runtime_map_entry(struct kobject *kobj, int nr)
                return ERR_PTR(-ENOMEM);
        }
 
-       memcpy(&entry->md, efi_runtime_map + nr * efi_memdesc_size,
-              sizeof(efi_memory_desc_t));
+       memcpy(&entry->md, md, sizeof(efi_memory_desc_t));
 
        kobject_init(&entry->kobj, &map_ktype);
        entry->kobj.kset = map_kset;
@@ -142,12 +138,12 @@ add_sysfs_runtime_map_entry(struct kobject *kobj, int nr)
 
 int efi_get_runtime_map_size(void)
 {
-       return nr_efi_runtime_map * efi_memdesc_size;
+       return efi.memmap.nr_map * efi.memmap.desc_size;
 }
 
 int efi_get_runtime_map_desc_size(void)
 {
-       return efi_memdesc_size;
+       return efi.memmap.desc_size;
 }
 
 int efi_runtime_map_copy(void *buf, size_t bufsz)
@@ -157,38 +153,33 @@ int efi_runtime_map_copy(void *buf, size_t bufsz)
        if (sz > bufsz)
                sz = bufsz;
 
-       memcpy(buf, efi_runtime_map, sz);
+       memcpy(buf, efi.memmap.map, sz);
        return 0;
 }
 
-void efi_runtime_map_setup(void *map, int nr_entries, u32 desc_size)
-{
-       efi_runtime_map = map;
-       nr_efi_runtime_map = nr_entries;
-       efi_memdesc_size = desc_size;
-}
-
 int __init efi_runtime_map_init(struct kobject *efi_kobj)
 {
        int i, j, ret = 0;
        struct efi_runtime_map_entry *entry;
+       efi_memory_desc_t *md;
 
-       if (!efi_runtime_map)
+       if (!efi_enabled(EFI_MEMMAP))
                return 0;
 
-       map_entries = kzalloc(nr_efi_runtime_map * sizeof(entry), GFP_KERNEL);
+       map_entries = kzalloc(efi.memmap.nr_map * sizeof(entry), GFP_KERNEL);
        if (!map_entries) {
                ret = -ENOMEM;
                goto out;
        }
 
-       for (i = 0; i < nr_efi_runtime_map; i++) {
-               entry = add_sysfs_runtime_map_entry(efi_kobj, i);
+       i = 0;
+       for_each_efi_memory_desc(md) {
+               entry = add_sysfs_runtime_map_entry(efi_kobj, i, md);
                if (IS_ERR(entry)) {
                        ret = PTR_ERR(entry);
                        goto out_add_entry;
                }
-               *(map_entries + i) = entry;
+               *(map_entries + i++) = entry;
        }
 
        return 0;

diff --git a/include/linux/efi.h b/include/linux/efi.h
index 3fe4f3c478342223af179497aaf7b548dfe2d3dd..d8b555db81c7cf505db5498c65951906b29a71a9 100644 (file)
--- a/include/linux/efi.h
+++ b/include/linux/efi.h
@@ -1357,7 +1357,6 @@ extern int efi_capsule_update(efi_capsule_header_t *capsule,
 
 #ifdef CONFIG_EFI_RUNTIME_MAP
 int efi_runtime_map_init(struct kobject *);
-void efi_runtime_map_setup(void *, int, u32);
 int efi_get_runtime_map_size(void);
 int efi_get_runtime_map_desc_size(void);
 int efi_runtime_map_copy(void *buf, size_t bufsz);
@@ -1367,9 +1366,6 @@ static inline int efi_runtime_map_init(struct kobject *kobj)
        return 0;
 }
 
-static inline void
-efi_runtime_map_setup(void *map, int nr_entries, u32 desc_size) {}
-
 static inline int efi_get_runtime_map_size(void)
 {
        return 0;