So we could use the left early pgt buf in BRK at first, then use new one.
We avoid wasting in _BRK.
Also we don't need to memblock_reserve that buf in brk again, because all
BRK is reserved before.
Signed-off-by: Yinghai Lu <ying...@kernel.org>
---
arch/x86/include/asm/init.h | 3 +++
arch/x86/mm/init.c | 24 +++++++++++-------------
arch/x86/mm/init_32.c | 8 ++++++--
arch/x86/mm/init_64.c | 8 ++++++--
4 files changed, 26 insertions(+), 17 deletions(-)
diff --git a/arch/x86/include/asm/init.h b/arch/x86/include/asm/init.h
index b69e537..6ce8718 100644
--- a/arch/x86/include/asm/init.h
+++ b/arch/x86/include/asm/init.h
@@ -15,6 +15,9 @@ kernel_physical_mapping_init(unsigned long start,
extern unsigned long __initdata pgt_buf_start;
extern unsigned long __meminitdata pgt_buf_end;
extern unsigned long __meminitdata pgt_buf_top;
+extern unsigned long __initdata early_pgt_buf_start;
+extern unsigned long __meminitdata early_pgt_buf_end;
+extern unsigned long __meminitdata early_pgt_buf_top;
bool is_pfn_in_early_pgt_buf(unsigned long pfn);
diff --git a/arch/x86/mm/init.c b/arch/x86/mm/init.c
index 1becfbd..34d47c3 100644
--- a/arch/x86/mm/init.c
+++ b/arch/x86/mm/init.c
@@ -20,10 +20,14 @@
unsigned long __initdata pgt_buf_start;
unsigned long __meminitdata pgt_buf_end;
unsigned long __meminitdata pgt_buf_top;
+unsigned long __initdata early_pgt_buf_start;
+unsigned long __meminitdata early_pgt_buf_end;
+unsigned long __meminitdata early_pgt_buf_top;
bool __init is_pfn_in_early_pgt_buf(unsigned long pfn)
{
- return pfn >= pgt_buf_start && pfn < pgt_buf_top;
+ return (pfn >= early_pgt_buf_start && pfn < early_pgt_buf_top) ||
+ (pfn >= pgt_buf_start && pfn < pgt_buf_top);
}
int after_bootmem;
@@ -325,16 +329,10 @@ static void __init find_early_table_space(unsigned long
start,
panic("Cannot find space for the kernel page tables");
init_memory_mapping(base, base + tables);
- if (pgt_buf_end > pgt_buf_start) {
+ if (early_pgt_buf_end > early_pgt_buf_start)
printk(KERN_DEBUG "kernel direct mapping tables from %#lx to
%#lx @ [mem %#010lx-%#010lx]\n",
- base, base + tables - 1, pgt_buf_start << PAGE_SHIFT,
- (pgt_buf_end << PAGE_SHIFT) - 1);
-
- memblock_reserve(PFN_PHYS(pgt_buf_start),
- PFN_PHYS(pgt_buf_end) -
PFN_PHYS(pgt_buf_start));
- }
- x86_init.mapping.make_range_readwrite(PFN_PHYS(pgt_buf_end),
- PFN_PHYS(pgt_buf_top));
+ base, base + tables - 1, early_pgt_buf_start <<
PAGE_SHIFT,
+ (early_pgt_buf_end << PAGE_SHIFT) - 1);
pgt_buf_start = base >> PAGE_SHIFT;
pgt_buf_end = pgt_buf_start;
@@ -493,9 +491,9 @@ void __init early_alloc_pgt_buf(void)
base = __pa(extend_brk(tables, PAGE_SIZE));
- pgt_buf_start = base >> PAGE_SHIFT;
- pgt_buf_end = pgt_buf_start;
- pgt_buf_top = pgt_buf_start + (tables >> PAGE_SHIFT);
+ early_pgt_buf_start = base >> PAGE_SHIFT;
+ early_pgt_buf_end = early_pgt_buf_start;
+ early_pgt_buf_top = early_pgt_buf_start + (tables >> PAGE_SHIFT);
}
/*
diff --git a/arch/x86/mm/init_32.c b/arch/x86/mm/init_32.c
index 27f7fc6..70fa732 100644
--- a/arch/x86/mm/init_32.c
+++ b/arch/x86/mm/init_32.c
@@ -61,10 +61,14 @@ bool __read_mostly __vmalloc_start_set = false;
static __init void *alloc_low_page(void)
{
- unsigned long pfn = pgt_buf_end++;
+ unsigned long pfn;
void *adr;
- if (pfn >= pgt_buf_top)
+ if (early_pgt_buf_end < early_pgt_buf_top)
+ pfn = early_pgt_buf_end++;
+ else if (pgt_buf_end < pgt_buf_top)
+ pfn = pgt_buf_end++;
+ else
panic("alloc_low_page: ran out of memory");
adr = __va(pfn * PAGE_SIZE);
diff --git a/arch/x86/mm/init_64.c b/arch/x86/mm/init_64.c
index aab1fc1..110c1e4 100644
--- a/arch/x86/mm/init_64.c
+++ b/arch/x86/mm/init_64.c
@@ -316,7 +316,7 @@ void __init cleanup_highmap(void)
static __ref void *alloc_low_page(unsigned long *phys)
{
- unsigned long pfn = pgt_buf_end++;
+ unsigned long pfn;
void *adr;
if (after_bootmem) {
@@ -326,7 +326,11 @@ static __ref void *alloc_low_page(unsigned long *phys)
return adr;
}
- if (pfn >= pgt_buf_top)
+ if (early_pgt_buf_end < early_pgt_buf_top)
+ pfn = early_pgt_buf_end++;
+ else if (pgt_buf_end < pgt_buf_top)
+ pfn = pgt_buf_end++;
+ else
panic("alloc_low_page: ran out of memory");
adr = __va(pfn * PAGE_SIZE);
--
1.7.7
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
