Current mem boot option only can work for non efi environment. If the user
specifies add_efi_memmap, it cannot work for efi environment. In
the efi environment, we call e820_add_region() to add the memory map. So
we can modify __e820_add_region() and the mem boot option can work for
efi environment.
Note: Only E820_RAM is limited, and BOOT_SERVICES_{CODE,DATA} are always
mapped(If its address >= mem_limit, the memory won't be freed in
efi_free_boot_services()).
Changelogs from v3 to v4:
1. address the comment from Matt Fleming <[email protected]>:
a. only ignoring E820_RAM entries that are above the mem_limit
b. don't ignore E820_RAM entries which are BOOT_SERVICES_{CODE,DATA} regions
Signed-off-by: Wen Congyang <[email protected]>
---
arch/x86/include/asm/e820.h | 2 ++
arch/x86/kernel/e820.c | 72 +++++++++++++++++++++++++++++++++++++++------
arch/x86/platform/efi/efi.c | 15 ++++++++--
3 files changed, 77 insertions(+), 12 deletions(-)
diff --git a/arch/x86/include/asm/e820.h b/arch/x86/include/asm/e820.h
index 3778256..c1f31ee 100644
--- a/arch/x86/include/asm/e820.h
+++ b/arch/x86/include/asm/e820.h
@@ -84,6 +84,8 @@ extern unsigned long pci_mem_start;
extern int e820_any_mapped(u64 start, u64 end, unsigned type);
extern int e820_all_mapped(u64 start, u64 end, unsigned type);
extern void e820_add_region(u64 start, u64 size, int type);
+extern void e820_add_limit_region(u64 start, u64 size, int type);
+extern void e820_adjust_region(u64 *start, u64 *size);
extern void e820_print_map(char *who);
extern int
sanitize_e820_map(struct e820entry *biosmap, int max_nr_map, u32 *pnr_map);
diff --git a/arch/x86/kernel/e820.c b/arch/x86/kernel/e820.c
index df06ade..7578c01 100644
--- a/arch/x86/kernel/e820.c
+++ b/arch/x86/kernel/e820.c
@@ -47,6 +47,7 @@ unsigned long pci_mem_start = 0xaeedbabe;
#ifdef CONFIG_PCI
EXPORT_SYMBOL(pci_mem_start);
#endif
+static u64 mem_limit = ~0ULL;
/*
* This function checks if any part of the range <start,end> is mapped
@@ -108,7 +109,7 @@ int __init e820_all_mapped(u64 start, u64 end, unsigned type)
* Add a memory region to the kernel e820 map.
*/
static void __init __e820_add_region(struct e820map *e820x, u64 start, u64 size,
- int type)
+ int type, bool limited)
{
int x = e820x->nr_map;
@@ -119,6 +120,22 @@ static void __init __e820_add_region(struct e820map *e820x, u64 start, u64 size,
return;
}
+ if (limited) {
+ if (start >= mem_limit) {
+ printk(KERN_ERR "e820: ignoring [mem %#010llx-%#010llx]\n",
+ (unsigned long long)start,
+ (unsigned long long)(start + size - 1));
+ return;
+ }
+
+ if (mem_limit - start < size) {
+ printk(KERN_ERR "e820: ignoring [mem %#010llx-%#010llx]\n",
+ (unsigned long long)mem_limit,
+ (unsigned long long)(start + size - 1));
+ size = mem_limit - start;
+ }
+ }
+
e820x->map[x].addr = start;
e820x->map[x].size = size;
e820x->map[x].type = type;
@@ -127,7 +144,37 @@ 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, false);
+}
+
+/*
+ * do_add_efi_memmap() calls this function().
+ *
+ * Note: BOOT_SERVICES_{CODE,DATA} regions on some efi machines are marked
+ * as E820_RAM, and they are needed to be mapped. Please use e820_add_region()
+ * to add BOOT_SERVICES_{CODE,DATA} regions.
+ */
+void __init e820_add_limit_region(u64 start, u64 size, int type)
+{
+ /*
+ * efi_init() is called after finish_e820_parsing(), so we should
+ * check whether [start, start + size) contains address above
+ * mem_limit if the type is E820_RAM.
+ */
+ __e820_add_region(&e820, start, size, type, type == E820_RAM);
+}
+
+void __init e820_adjust_region(u64 *start, u64 *size)
+{
+ if (*start >= mem_limit) {
+ *size = 0;
+ return;
+ }
+
+ if (mem_limit - *start < *size)
+ *size = mem_limit - *start;
+
+ return;
}
static void __init e820_print_type(u32 type)
@@ -455,8 +502,9 @@ static u64 __init __e820_update_range(struct e820map *e820x, u64 start,
/* new range is totally covered? */
if (ei->addr < start && ei_end > end) {
- __e820_add_region(e820x, start, size, new_type);
- __e820_add_region(e820x, end, ei_end - end, ei->type);
+ __e820_add_region(e820x, start, size, new_type, false);
+ __e820_add_region(e820x, end, ei_end - end, ei->type,
+ false);
ei->size = start - ei->addr;
real_updated_size += size;
continue;
@@ -469,7 +517,7 @@ static u64 __init __e820_update_range(struct e820map *e820x, u64 start,
continue;
__e820_add_region(e820x, final_start, final_end - final_start,
- new_type);
+ new_type, false);
real_updated_size += final_end - final_start;
@@ -809,7 +857,7 @@ static int userdef __initdata;
/* "mem=nopentium" disables the 4MB page tables. */
static int __init parse_memopt(char *p)
{
- u64 mem_size;
+ char *oldp;
if (!p)
return -EINVAL;
@@ -825,11 +873,11 @@ static int __init parse_memopt(char *p)
}
userdef = 1;
- mem_size = memparse(p, &p);
+ oldp = p;
+ mem_limit = memparse(p, &p);
/* don't remove all of memory when handling "mem={invalid}" param */
- if (mem_size == 0)
+ if (mem_limit == 0 || p == oldp)
return -EINVAL;
- e820_remove_range(mem_size, ULLONG_MAX - mem_size, E820_RAM, 1);
return 0;
}
@@ -881,6 +929,12 @@ early_param("memmap", parse_memmap_opt);
void __init finish_e820_parsing(void)
{
+ if (mem_limit != ~0ULL) {
+ userdef = 1;
+ e820_remove_range(mem_limit, ULLONG_MAX - mem_limit,
+ E820_RAM, 1);
+ }
+
if (userdef) {
u32 nr = e820.nr_map;
diff --git a/arch/x86/platform/efi/efi.c b/arch/x86/platform/efi/efi.c
index ad44391..7592163 100644
--- a/arch/x86/platform/efi/efi.c
+++ b/arch/x86/platform/efi/efi.c
@@ -314,10 +314,17 @@ static void __init do_add_efi_memmap(void)
int e820_type;
switch (md->type) {
- case EFI_LOADER_CODE:
- case EFI_LOADER_DATA:
case EFI_BOOT_SERVICES_CODE:
case EFI_BOOT_SERVICES_DATA:
+ /* EFI_BOOT_SERVICES_{CODE,DATA} needs to be mapped */
+ if (md->attribute & EFI_MEMORY_WB)
+ e820_type = E820_RAM;
+ else
+ e820_type = E820_RESERVED;
+ e820_add_region(start, size, e820_type);
+ continue;
+ case EFI_LOADER_CODE:
+ case EFI_LOADER_DATA:
case EFI_CONVENTIONAL_MEMORY:
if (md->attribute & EFI_MEMORY_WB)
e820_type = E820_RAM;
@@ -342,7 +349,7 @@ static void __init do_add_efi_memmap(void)
e820_type = E820_RESERVED;
break;
}
- e820_add_region(start, size, e820_type);
+ e820_add_limit_region(start, size, e820_type);
}
sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &e820.nr_map);
}
@@ -448,6 +455,8 @@ void __init efi_free_boot_services(void)
md->type != EFI_BOOT_SERVICES_DATA)
continue;
+ e820_adjust_region(&start, &size);
+
/* Could not reserve boot area */
if (!size)
continue;
--
1.8.0