[PATCH 2/3] x86/e820: Prepare e280 code for switch to dynamic storage
From: Denys Vlasenko
Date: Sat Sep 17 2016 - 17:39:54 EST
This patch turns e820 and e820_saved into pointers to e820 tables,
of the same size as before.
Signed-off-by: Denys Vlasenko <dvlasenk@xxxxxxxxxx>
CC: Ingo Molnar <mingo@xxxxxxxxxx>
CC: Andy Lutomirski <luto@xxxxxxxxxxxxxx>
CC: "H. Peter Anvin" <hpa@xxxxxxxxx>
CC: Borislav Petkov <bp@xxxxxxxxx>
CC: Brian Gerst <brgerst@xxxxxxxxx>
CC: x86@xxxxxxxxxx
CC: linux-kernel@xxxxxxxxxxxxxxx
Signed-off-by: Denys Vlasenko <dvlasenk@xxxxxxxxxx>
---
arch/x86/include/asm/e820.h | 6 +-
arch/x86/kernel/e820.c | 125 +++++++++++++++++++++++---------------
arch/x86/kernel/early-quirks.c | 2 +-
arch/x86/kernel/kexec-bzimage64.c | 4 +-
arch/x86/kernel/resource.c | 4 +-
arch/x86/kernel/setup.c | 8 +--
arch/x86/kernel/tboot.c | 8 +--
arch/x86/mm/init.c | 2 +
arch/x86/platform/efi/efi.c | 2 +-
arch/x86/xen/setup.c | 2 +-
10 files changed, 98 insertions(+), 65 deletions(-)
diff --git a/arch/x86/include/asm/e820.h b/arch/x86/include/asm/e820.h
index 3ab0537..476b574 100644
--- a/arch/x86/include/asm/e820.h
+++ b/arch/x86/include/asm/e820.h
@@ -10,8 +10,8 @@
#include <uapi/asm/e820.h>
#ifndef __ASSEMBLY__
/* see comment in arch/x86/kernel/e820.c */
-extern struct e820map e820;
-extern struct e820map e820_saved;
+extern struct e820map *e820;
+extern struct e820map *e820_saved;
extern unsigned long pci_mem_start;
extern int e820_any_mapped(u64 start, u64 end, unsigned type);
@@ -53,6 +53,8 @@ extern void e820_reserve_resources_late(void);
extern void setup_memory_map(void);
extern char *default_machine_specific_memory_setup(void);
+extern void e820_reallocate_tables(void);
+
/*
* Returns true iff the specified range [s,e) is completely contained inside
* the ISA region.
diff --git a/arch/x86/kernel/e820.c b/arch/x86/kernel/e820.c
index a6d4f10..cf7c9ad 100644
--- a/arch/x86/kernel/e820.c
+++ b/arch/x86/kernel/e820.c
@@ -40,8 +40,10 @@
* user can e.g. boot the original kernel with mem=1G while still booting the
* next kernel with full memory.
*/
-struct e820map e820;
-struct e820map e820_saved;
+static struct e820map initial_e820;
+static struct e820map initial_e820_saved;
+struct e820map *e820 = &initial_e820;
+struct e820map *e820_saved = &initial_e820_saved;
/* For PCI or other memory-mapped resources */
unsigned long pci_mem_start = 0xaeedbabe;
@@ -58,8 +60,8 @@ e820_any_mapped(u64 start, u64 end, unsigned type)
{
int i;
- for (i = 0; i < e820.nr_map; i++) {
- struct e820entry *ei = &e820.map[i];
+ for (i = 0; i < e820->nr_map; i++) {
+ struct e820entry *ei = &e820->map[i];
if (type && ei->type != type)
continue;
@@ -81,8 +83,8 @@ int __init e820_all_mapped(u64 start, u64 end, unsigned type)
{
int i;
- for (i = 0; i < e820.nr_map; i++) {
- struct e820entry *ei = &e820.map[i];
+ for (i = 0; i < e820->nr_map; i++) {
+ struct e820entry *ei = &e820->map[i];
if (type && ei->type != type)
continue;
@@ -128,7 +130,7 @@ static void __init __e820_add_region(struct e820map *e820x, u64 start, u64 size,
void __init e820_add_region(u64 start, u64 size, int type)
{
- __e820_add_region(&e820, start, size, type);
+ __e820_add_region(e820, start, size, type);
}
static void __init e820_print_type(u32 type)
@@ -164,12 +166,12 @@ void __init e820_print_map(char *who)
{
int i;
- for (i = 0; i < e820.nr_map; i++) {
+ for (i = 0; i < e820->nr_map; i++) {
printk(KERN_INFO "%s: [mem %#018Lx-%#018Lx] ", who,
- (unsigned long long) e820.map[i].addr,
+ (unsigned long long) e820->map[i].addr,
(unsigned long long)
- (e820.map[i].addr + e820.map[i].size - 1));
- e820_print_type(e820.map[i].type);
+ (e820->map[i].addr + e820->map[i].size - 1));
+ e820_print_type(e820->map[i].type);
printk(KERN_CONT "\n");
}
}
@@ -493,13 +495,13 @@ static u64 __init __e820_update_range(struct e820map *e820x, u64 start,
u64 __init e820_update_range(u64 start, u64 size, unsigned old_type,
unsigned new_type)
{
- return __e820_update_range(&e820, start, size, old_type, new_type);
+ return __e820_update_range(e820, start, size, old_type, new_type);
}
static u64 __init e820_update_range_saved(u64 start, u64 size,
unsigned old_type, unsigned new_type)
{
- return __e820_update_range(&e820_saved, start, size, old_type,
+ return __e820_update_range(e820_saved, start, size, old_type,
new_type);
}
@@ -521,8 +523,8 @@ u64 __init e820_remove_range(u64 start, u64 size, unsigned old_type,
e820_print_type(old_type);
printk(KERN_CONT "\n");
- for (i = 0; i < e820.nr_map; i++) {
- struct e820entry *ei = &e820.map[i];
+ for (i = 0; i < e820->nr_map; i++) {
+ struct e820entry *ei = &e820->map[i];
u64 final_start, final_end;
u64 ei_end;
@@ -566,15 +568,15 @@ u64 __init e820_remove_range(u64 start, u64 size, unsigned old_type,
void __init update_e820(void)
{
- if (sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &e820.nr_map))
+ if (sanitize_e820_map(e820->map, ARRAY_SIZE(e820->map), &e820->nr_map))
return;
printk(KERN_INFO "e820: modified physical RAM map:\n");
e820_print_map("modified");
}
static void __init update_e820_saved(void)
{
- sanitize_e820_map(e820_saved.map, ARRAY_SIZE(e820_saved.map),
- &e820_saved.nr_map);
+ sanitize_e820_map(e820_saved->map, ARRAY_SIZE(e820_saved->map),
+ &e820_saved->nr_map);
}
#define MAX_GAP_END 0x100000000ull
/*
@@ -584,14 +586,14 @@ __init int e820_search_gap(unsigned long *gapstart, unsigned long *gapsize,
unsigned long start_addr, unsigned long long end_addr)
{
unsigned long long last;
- int i = e820.nr_map;
+ int i = e820->nr_map;
int found = 0;
last = (end_addr && end_addr < MAX_GAP_END) ? end_addr : MAX_GAP_END;
while (--i >= 0) {
- unsigned long long start = e820.map[i].addr;
- unsigned long long end = start + e820.map[i].size;
+ unsigned long long start = e820->map[i].addr;
+ unsigned long long end = start + e820->map[i].size;
if (end < start_addr)
continue;
@@ -649,6 +651,33 @@ __init void e820_setup_gap(void)
gapstart, gapstart + gapsize - 1);
}
+/*
+ * Called late during init, in free_initmem().
+ *
+ * Initial e820 and e820_saved are largish __initdata arrays.
+ * Copy them to (usually much smaller) dynamically allocated area.
+ * This is done after all tweaks we ever do to them:
+ * all functions which modify them are __init functions,
+ * they won't exist after this point.
+ */
+__init void e820_reallocate_tables(void)
+{
+ struct e820map *n;
+ int size;
+
+ size = offsetof(struct e820map, map) + sizeof(struct e820entry) * e820->nr_map;
+ n = kmalloc(size, GFP_KERNEL);
+ BUG_ON(!n);
+ memcpy(n, e820, size);
+ e820 = n;
+
+ size = offsetof(struct e820map, map) + sizeof(struct e820entry) * e820_saved->nr_map;
+ n = kmalloc(size, GFP_KERNEL);
+ BUG_ON(!n);
+ memcpy(n, e820_saved, size);
+ e820_saved = n;
+}
+
/**
* Because of the size limitation of struct boot_params, only first
* 128 E820 memory entries are passed to kernel via
@@ -665,7 +694,7 @@ void __init parse_e820_ext(u64 phys_addr, u32 data_len)
entries = sdata->len / sizeof(struct e820entry);
extmap = (struct e820entry *)(sdata->data);
__append_e820_map(extmap, entries);
- sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &e820.nr_map);
+ sanitize_e820_map(e820->map, ARRAY_SIZE(e820->map), &e820->nr_map);
early_memunmap(sdata, data_len);
printk(KERN_INFO "e820: extended physical RAM map:\n");
e820_print_map("extended");
@@ -686,8 +715,8 @@ void __init e820_mark_nosave_regions(unsigned long limit_pfn)
int i;
unsigned long pfn = 0;
- for (i = 0; i < e820.nr_map; i++) {
- struct e820entry *ei = &e820.map[i];
+ for (i = 0; i < e820->nr_map; i++) {
+ struct e820entry *ei = &e820->map[i];
if (pfn < PFN_UP(ei->addr))
register_nosave_region(pfn, PFN_UP(ei->addr));
@@ -712,8 +741,8 @@ static int __init e820_mark_nvs_memory(void)
{
int i;
- for (i = 0; i < e820.nr_map; i++) {
- struct e820entry *ei = &e820.map[i];
+ for (i = 0; i < e820->nr_map; i++) {
+ struct e820entry *ei = &e820->map[i];
if (ei->type == E820_NVS)
acpi_nvs_register(ei->addr, ei->size);
@@ -760,8 +789,8 @@ static unsigned long __init e820_end_pfn(unsigned long limit_pfn)
unsigned long last_pfn = 0;
unsigned long max_arch_pfn = MAX_ARCH_PFN;
- for (i = 0; i < e820.nr_map; i++) {
- struct e820entry *ei = &e820.map[i];
+ for (i = 0; i < e820->nr_map; i++) {
+ struct e820entry *ei = &e820->map[i];
unsigned long start_pfn;
unsigned long end_pfn;
@@ -856,7 +885,7 @@ static int __init parse_memmap_one(char *p)
*/
saved_max_pfn = e820_end_of_ram_pfn();
#endif
- e820.nr_map = 0;
+ e820->nr_map = 0;
userdef = 1;
return 0;
}
@@ -903,8 +932,8 @@ early_param("memmap", parse_memmap_opt);
void __init finish_e820_parsing(void)
{
if (userdef) {
- if (sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map),
- &e820.nr_map) < 0)
+ if (sanitize_e820_map(e820->map, ARRAY_SIZE(e820->map),
+ &e820->nr_map) < 0)
early_panic("Invalid user supplied memory map");
printk(KERN_INFO "e820: user-defined physical RAM map:\n");
@@ -991,35 +1020,35 @@ void __init e820_reserve_resources(void)
struct resource *res;
u64 end;
- res = alloc_bootmem(sizeof(struct resource) * e820.nr_map);
+ res = alloc_bootmem(sizeof(struct resource) * e820->nr_map);
e820_res = res;
- for (i = 0; i < e820.nr_map; i++) {
- end = e820.map[i].addr + e820.map[i].size - 1;
+ for (i = 0; i < e820->nr_map; i++) {
+ end = e820->map[i].addr + e820->map[i].size - 1;
if (end != (resource_size_t)end) {
res++;
continue;
}
- res->name = e820_type_to_string(e820.map[i].type);
- res->start = e820.map[i].addr;
+ res->name = e820_type_to_string(e820->map[i].type);
+ res->start = e820->map[i].addr;
res->end = end;
- res->flags = e820_type_to_iomem_type(e820.map[i].type);
- res->desc = e820_type_to_iores_desc(e820.map[i].type);
+ res->flags = e820_type_to_iomem_type(e820->map[i].type);
+ res->desc = e820_type_to_iores_desc(e820->map[i].type);
/*
* don't register the region that could be conflicted with
* pci device BAR resource and insert them later in
* pcibios_resource_survey()
*/
- if (do_mark_busy(e820.map[i].type, res)) {
+ if (do_mark_busy(e820->map[i].type, res)) {
res->flags |= IORESOURCE_BUSY;
insert_resource(&iomem_resource, res);
}
res++;
}
- for (i = 0; i < e820_saved.nr_map; i++) {
- struct e820entry *entry = &e820_saved.map[i];
+ for (i = 0; i < e820_saved->nr_map; i++) {
+ struct e820entry *entry = &e820_saved->map[i];
firmware_map_add_early(entry->addr,
entry->addr + entry->size,
e820_type_to_string(entry->type));
@@ -1051,7 +1080,7 @@ void __init e820_reserve_resources_late(void)
struct resource *res;
res = e820_res;
- for (i = 0; i < e820.nr_map; i++) {
+ for (i = 0; i < e820->nr_map; i++) {
if (!res->parent && res->end)
insert_resource_expand_to_fit(&iomem_resource, res);
res++;
@@ -1061,8 +1090,8 @@ void __init e820_reserve_resources_late(void)
* Try to bump up RAM regions to reasonable boundaries to
* avoid stolen RAM:
*/
- for (i = 0; i < e820.nr_map; i++) {
- struct e820entry *entry = &e820.map[i];
+ for (i = 0; i < e820->nr_map; i++) {
+ struct e820entry *entry = &e820->map[i];
u64 start, end;
if (entry->type != E820_RAM)
@@ -1110,7 +1139,7 @@ char *__init default_machine_specific_memory_setup(void)
who = "BIOS-e801";
}
- e820.nr_map = 0;
+ e820->nr_map = 0;
e820_add_region(0, LOWMEMSIZE(), E820_RAM);
e820_add_region(HIGH_MEMORY, mem_size << 10, E820_RAM);
}
@@ -1124,7 +1153,7 @@ void __init setup_memory_map(void)
char *who;
who = x86_init.resources.memory_setup();
- memcpy(&e820_saved, &e820, sizeof(struct e820map));
+ memcpy(e820_saved, e820, sizeof(struct e820map));
printk(KERN_INFO "e820: BIOS-provided physical RAM map:\n");
e820_print_map(who);
}
@@ -1141,8 +1170,8 @@ void __init memblock_x86_fill(void)
*/
memblock_allow_resize();
- for (i = 0; i < e820.nr_map; i++) {
- struct e820entry *ei = &e820.map[i];
+ for (i = 0; i < e820->nr_map; i++) {
+ struct e820entry *ei = &e820->map[i];
end = ei->addr + ei->size;
if (end != (resource_size_t)end)
diff --git a/arch/x86/kernel/early-quirks.c b/arch/x86/kernel/early-quirks.c
index de7501e..18bb3a6 100644
--- a/arch/x86/kernel/early-quirks.c
+++ b/arch/x86/kernel/early-quirks.c
@@ -555,7 +555,7 @@ intel_graphics_stolen(int num, int slot, int func,
/* Mark this space as reserved */
e820_add_region(base, size, E820_RESERVED);
- sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &e820.nr_map);
+ sanitize_e820_map(e820->map, ARRAY_SIZE(e820->map), &e820->nr_map);
}
static void __init intel_graphics_quirks(int num, int slot, int func)
diff --git a/arch/x86/kernel/kexec-bzimage64.c b/arch/x86/kernel/kexec-bzimage64.c
index f2356bd..3407b14 100644
--- a/arch/x86/kernel/kexec-bzimage64.c
+++ b/arch/x86/kernel/kexec-bzimage64.c
@@ -99,14 +99,14 @@ static int setup_e820_entries(struct boot_params *params)
{
unsigned int nr_e820_entries;
- nr_e820_entries = e820_saved.nr_map;
+ nr_e820_entries = e820_saved->nr_map;
/* TODO: Pass entries more than E820MAX in bootparams setup data */
if (nr_e820_entries > E820MAX)
nr_e820_entries = E820MAX;
params->e820_entries = nr_e820_entries;
- memcpy(¶ms->e820_map, &e820_saved.map,
+ memcpy(¶ms->e820_map, &e820_saved->map,
nr_e820_entries * sizeof(struct e820entry));
return 0;
diff --git a/arch/x86/kernel/resource.c b/arch/x86/kernel/resource.c
index 80eab01..2408c16 100644
--- a/arch/x86/kernel/resource.c
+++ b/arch/x86/kernel/resource.c
@@ -27,8 +27,8 @@ static void remove_e820_regions(struct resource *avail)
int i;
struct e820entry *entry;
- for (i = 0; i < e820.nr_map; i++) {
- entry = &e820.map[i];
+ for (i = 0; i < e820->nr_map; i++) {
+ entry = &e820->map[i];
resource_clip(avail, entry->addr,
entry->addr + entry->size - 1);
diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
index 0fa60f5..cc43d66 100644
--- a/arch/x86/kernel/setup.c
+++ b/arch/x86/kernel/setup.c
@@ -458,8 +458,8 @@ static void __init e820_reserve_setup_data(void)
early_memunmap(data, sizeof(*data));
}
- sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &e820.nr_map);
- memcpy(&e820_saved, &e820, sizeof(struct e820map));
+ sanitize_e820_map(e820->map, ARRAY_SIZE(e820->map), &e820->nr_map);
+ memcpy(e820_saved, e820, sizeof(struct e820map));
printk(KERN_INFO "extended physical RAM map:\n");
e820_print_map("reserve setup_data");
}
@@ -763,7 +763,7 @@ static void __init trim_bios_range(void)
*/
e820_remove_range(BIOS_BEGIN, BIOS_END - BIOS_BEGIN, E820_RAM, 1);
- sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &e820.nr_map);
+ sanitize_e820_map(e820->map, ARRAY_SIZE(e820->map), &e820->nr_map);
}
/* called before trim_bios_range() to spare extra sanitize */
@@ -1032,7 +1032,7 @@ void __init setup_arch(char **cmdline_p)
if (ppro_with_ram_bug()) {
e820_update_range(0x70000000ULL, 0x40000ULL, E820_RAM,
E820_RESERVED);
- sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &e820.nr_map);
+ sanitize_e820_map(e820->map, ARRAY_SIZE(e820->map), &e820->nr_map);
printk(KERN_INFO "fixed physical RAM map:\n");
e820_print_map("bad_ppro");
}
diff --git a/arch/x86/kernel/tboot.c b/arch/x86/kernel/tboot.c
index 654f6c6..8402907 100644
--- a/arch/x86/kernel/tboot.c
+++ b/arch/x86/kernel/tboot.c
@@ -188,12 +188,12 @@ static int tboot_setup_sleep(void)
tboot->num_mac_regions = 0;
- for (i = 0; i < e820.nr_map; i++) {
- if ((e820.map[i].type != E820_RAM)
- && (e820.map[i].type != E820_RESERVED_KERN))
+ for (i = 0; i < e820->nr_map; i++) {
+ if ((e820->map[i].type != E820_RAM)
+ && (e820->map[i].type != E820_RESERVED_KERN))
continue;
- add_mac_region(e820.map[i].addr, e820.map[i].size);
+ add_mac_region(e820->map[i].addr, e820->map[i].size);
}
tboot->acpi_sinfo.kernel_s3_resume_vector =
diff --git a/arch/x86/mm/init.c b/arch/x86/mm/init.c
index d28a2d7..167deae 100644
--- a/arch/x86/mm/init.c
+++ b/arch/x86/mm/init.c
@@ -701,6 +701,8 @@ void free_init_pages(char *what, unsigned long begin, unsigned long end)
void free_initmem(void)
{
+ /* e820_reallocate_tables(); - disabled for now */
+
free_init_pages("unused kernel",
(unsigned long)(&__init_begin),
(unsigned long)(&__init_end));
diff --git a/arch/x86/platform/efi/efi.c b/arch/x86/platform/efi/efi.c
index 1fbb408..2e34334 100644
--- a/arch/x86/platform/efi/efi.c
+++ b/arch/x86/platform/efi/efi.c
@@ -166,7 +166,7 @@ static void __init do_add_efi_memmap(void)
}
e820_add_region(start, size, e820_type);
}
- sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &e820.nr_map);
+ sanitize_e820_map(e820->map, ARRAY_SIZE(e820->map), &e820->nr_map);
}
int __init efi_memblock_x86_reserve_range(void)
diff --git a/arch/x86/xen/setup.c b/arch/x86/xen/setup.c
index 1764252..f8960fc 100644
--- a/arch/x86/xen/setup.c
+++ b/arch/x86/xen/setup.c
@@ -861,7 +861,7 @@ char * __init xen_memory_setup(void)
e820_add_region(ISA_START_ADDRESS, ISA_END_ADDRESS - ISA_START_ADDRESS,
E820_RESERVED);
- sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &e820.nr_map);
+ sanitize_e820_map(e820->map, ARRAY_SIZE(e820->map), &e820->nr_map);
/*
* Check whether the kernel itself conflicts with the target E820 map.
--
2.9.2