Skip to content

Commit

Permalink
x86: move init_memory_mapping() to common mm/init.c
Browse files Browse the repository at this point in the history 
Impact: cleanup

This patch moves the init_memory_mapping() function to common mm/init.c.

Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: Yinghai Lu <yinghai@kernel.org>
LKML-Reference: <1236257708-27269-14-git-send-email-penberg@cs.helsinki.fi>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
  • Loading branch information
Pekka Enberg authored and Ingo Molnar committed Mar 5, 2009
1 parent 0c0f756 commit f765090
Show file tree
Hide file tree
Showing 3 changed files with 342 additions and 608 deletions.
328 changes: 328 additions & 0 deletions arch/x86/mm/init.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -2,10 +2,338 @@
#include <linux/swap.h>

#include <asm/cacheflush.h>
#include <asm/e820.h>
#include <asm/page.h>
#include <asm/page_types.h>
#include <asm/sections.h>
#include <asm/system.h>
#include <asm/tlbflush.h>

#ifdef CONFIG_X86_32
extern void __init early_ioremap_page_table_range_init(void);
extern void __init kernel_physical_mapping_init(unsigned long start_pfn,
unsigned long end_pfn,
int use_pse);
#endif

#ifdef CONFIG_X86_64
extern unsigned long __meminit
kernel_physical_mapping_init(unsigned long start,
unsigned long end,
unsigned long page_size_mask);
#endif

unsigned long __initdata table_start;
unsigned long __meminitdata table_end;
unsigned long __meminitdata table_top;

int after_bootmem;

int direct_gbpages
#ifdef CONFIG_DIRECT_GBPAGES
= 1
#endif
;

static void __init find_early_table_space(unsigned long end, int use_pse,
int use_gbpages)
{
unsigned long puds, pmds, ptes, tables, start;

puds = (end + PUD_SIZE - 1) >> PUD_SHIFT;
tables = roundup(puds * sizeof(pud_t), PAGE_SIZE);

if (use_gbpages) {
unsigned long extra;

extra = end - ((end>>PUD_SHIFT) << PUD_SHIFT);
pmds = (extra + PMD_SIZE - 1) >> PMD_SHIFT;
} else
pmds = (end + PMD_SIZE - 1) >> PMD_SHIFT;

tables += roundup(pmds * sizeof(pmd_t), PAGE_SIZE);

if (use_pse) {
unsigned long extra;

extra = end - ((end>>PMD_SHIFT) << PMD_SHIFT);
#ifdef CONFIG_X86_32
extra += PMD_SIZE;
#endif
ptes = (extra + PAGE_SIZE - 1) >> PAGE_SHIFT;
} else
ptes = (end + PAGE_SIZE - 1) >> PAGE_SHIFT;

tables += roundup(ptes * sizeof(pte_t), PAGE_SIZE);

#ifdef CONFIG_X86_32
/* for fixmap */
tables += roundup(__end_of_fixed_addresses * sizeof(pte_t), PAGE_SIZE);
#endif

/*
* RED-PEN putting page tables only on node 0 could
* cause a hotspot and fill up ZONE_DMA. The page tables
* need roughly 0.5KB per GB.
*/
#ifdef CONFIG_X86_32
start = 0x7000;
table_start = find_e820_area(start, max_pfn_mapped<<PAGE_SHIFT,
tables, PAGE_SIZE);
#else /* CONFIG_X86_64 */
start = 0x8000;
table_start = find_e820_area(start, end, tables, PAGE_SIZE);
#endif
if (table_start == -1UL)
panic("Cannot find space for the kernel page tables");

table_start >>= PAGE_SHIFT;
table_end = table_start;
table_top = table_start + (tables >> PAGE_SHIFT);

printk(KERN_DEBUG "kernel direct mapping tables up to %lx @ %lx-%lx\n",
end, table_start << PAGE_SHIFT, table_top << PAGE_SHIFT);
}

struct map_range {
unsigned long start;
unsigned long end;
unsigned page_size_mask;
};

#ifdef CONFIG_X86_32
#define NR_RANGE_MR 3
#else /* CONFIG_X86_64 */
#define NR_RANGE_MR 5
#endif

static int save_mr(struct map_range *mr, int nr_range,
unsigned long start_pfn, unsigned long end_pfn,
unsigned long page_size_mask)
{
if (start_pfn < end_pfn) {
if (nr_range >= NR_RANGE_MR)
panic("run out of range for init_memory_mapping\n");
mr[nr_range].start = start_pfn<<PAGE_SHIFT;
mr[nr_range].end = end_pfn<<PAGE_SHIFT;
mr[nr_range].page_size_mask = page_size_mask;
nr_range++;
}

return nr_range;
}

#ifdef CONFIG_X86_64
static void __init init_gbpages(void)
{
if (direct_gbpages && cpu_has_gbpages)
printk(KERN_INFO "Using GB pages for direct mapping\n");
else
direct_gbpages = 0;
}
#else
static inline void init_gbpages(void)
{
}
#endif

/*
* Setup the direct mapping of the physical memory at PAGE_OFFSET.
* This runs before bootmem is initialized and gets pages directly from
* the physical memory. To access them they are temporarily mapped.
*/
unsigned long __init_refok init_memory_mapping(unsigned long start,
unsigned long end)
{
unsigned long page_size_mask = 0;
unsigned long start_pfn, end_pfn;
unsigned long pos;
unsigned long ret;

struct map_range mr[NR_RANGE_MR];
int nr_range, i;
int use_pse, use_gbpages;

printk(KERN_INFO "init_memory_mapping: %016lx-%016lx\n", start, end);

if (!after_bootmem)
init_gbpages();

#ifdef CONFIG_DEBUG_PAGEALLOC
/*
* For CONFIG_DEBUG_PAGEALLOC, identity mapping will use small pages.
* This will simplify cpa(), which otherwise needs to support splitting
* large pages into small in interrupt context, etc.
*/
use_pse = use_gbpages = 0;
#else
use_pse = cpu_has_pse;
use_gbpages = direct_gbpages;
#endif

#ifdef CONFIG_X86_32
#ifdef CONFIG_X86_PAE
set_nx();
if (nx_enabled)
printk(KERN_INFO "NX (Execute Disable) protection: active\n");
#endif

/* Enable PSE if available */
if (cpu_has_pse)
set_in_cr4(X86_CR4_PSE);

/* Enable PGE if available */
if (cpu_has_pge) {
set_in_cr4(X86_CR4_PGE);
__supported_pte_mask |= _PAGE_GLOBAL;
}
#endif

if (use_gbpages)
page_size_mask |= 1 << PG_LEVEL_1G;
if (use_pse)
page_size_mask |= 1 << PG_LEVEL_2M;

memset(mr, 0, sizeof(mr));
nr_range = 0;

/* head if not big page alignment ? */
start_pfn = start >> PAGE_SHIFT;
pos = start_pfn << PAGE_SHIFT;
#ifdef CONFIG_X86_32
/*
* Don't use a large page for the first 2/4MB of memory
* because there are often fixed size MTRRs in there
* and overlapping MTRRs into large pages can cause
* slowdowns.
*/
if (pos == 0)
end_pfn = 1<<(PMD_SHIFT - PAGE_SHIFT);
else
end_pfn = ((pos + (PMD_SIZE - 1))>>PMD_SHIFT)
<< (PMD_SHIFT - PAGE_SHIFT);
#else /* CONFIG_X86_64 */
end_pfn = ((pos + (PMD_SIZE - 1)) >> PMD_SHIFT)
<< (PMD_SHIFT - PAGE_SHIFT);
#endif
if (end_pfn > (end >> PAGE_SHIFT))
end_pfn = end >> PAGE_SHIFT;
if (start_pfn < end_pfn) {
nr_range = save_mr(mr, nr_range, start_pfn, end_pfn, 0);
pos = end_pfn << PAGE_SHIFT;
}

/* big page (2M) range */
start_pfn = ((pos + (PMD_SIZE - 1))>>PMD_SHIFT)
<< (PMD_SHIFT - PAGE_SHIFT);
#ifdef CONFIG_X86_32
end_pfn = (end>>PMD_SHIFT) << (PMD_SHIFT - PAGE_SHIFT);
#else /* CONFIG_X86_64 */
end_pfn = ((pos + (PUD_SIZE - 1))>>PUD_SHIFT)
<< (PUD_SHIFT - PAGE_SHIFT);
if (end_pfn > ((end>>PMD_SHIFT)<<(PMD_SHIFT - PAGE_SHIFT)))
end_pfn = ((end>>PMD_SHIFT)<<(PMD_SHIFT - PAGE_SHIFT));
#endif

if (start_pfn < end_pfn) {
nr_range = save_mr(mr, nr_range, start_pfn, end_pfn,
page_size_mask & (1<<PG_LEVEL_2M));
pos = end_pfn << PAGE_SHIFT;
}

#ifdef CONFIG_X86_64
/* big page (1G) range */
start_pfn = ((pos + (PUD_SIZE - 1))>>PUD_SHIFT)
<< (PUD_SHIFT - PAGE_SHIFT);
end_pfn = (end >> PUD_SHIFT) << (PUD_SHIFT - PAGE_SHIFT);
if (start_pfn < end_pfn) {
nr_range = save_mr(mr, nr_range, start_pfn, end_pfn,
page_size_mask &
((1<<PG_LEVEL_2M)|(1<<PG_LEVEL_1G)));
pos = end_pfn << PAGE_SHIFT;
}

/* tail is not big page (1G) alignment */
start_pfn = ((pos + (PMD_SIZE - 1))>>PMD_SHIFT)
<< (PMD_SHIFT - PAGE_SHIFT);
end_pfn = (end >> PMD_SHIFT) << (PMD_SHIFT - PAGE_SHIFT);
if (start_pfn < end_pfn) {
nr_range = save_mr(mr, nr_range, start_pfn, end_pfn,
page_size_mask & (1<<PG_LEVEL_2M));
pos = end_pfn << PAGE_SHIFT;
}
#endif

/* tail is not big page (2M) alignment */
start_pfn = pos>>PAGE_SHIFT;
end_pfn = end>>PAGE_SHIFT;
nr_range = save_mr(mr, nr_range, start_pfn, end_pfn, 0);

/* try to merge same page size and continuous */
for (i = 0; nr_range > 1 && i < nr_range - 1; i++) {
unsigned long old_start;
if (mr[i].end != mr[i+1].start ||
mr[i].page_size_mask != mr[i+1].page_size_mask)
continue;
/* move it */
old_start = mr[i].start;
memmove(&mr[i], &mr[i+1],
(nr_range - 1 - i) * sizeof(struct map_range));
mr[i--].start = old_start;
nr_range--;
}

for (i = 0; i < nr_range; i++)
printk(KERN_DEBUG " %010lx - %010lx page %s\n",
mr[i].start, mr[i].end,
(mr[i].page_size_mask & (1<<PG_LEVEL_1G))?"1G":(
(mr[i].page_size_mask & (1<<PG_LEVEL_2M))?"2M":"4k"));

/*
* Find space for the kernel direct mapping tables.
*
* Later we should allocate these tables in the local node of the
* memory mapped. Unfortunately this is done currently before the
* nodes are discovered.
*/
if (!after_bootmem)
find_early_table_space(end, use_pse, use_gbpages);

#ifdef CONFIG_X86_32
for (i = 0; i < nr_range; i++)
kernel_physical_mapping_init(
mr[i].start >> PAGE_SHIFT,
mr[i].end >> PAGE_SHIFT,
mr[i].page_size_mask == (1<<PG_LEVEL_2M));
ret = end;
#else /* CONFIG_X86_64 */
for (i = 0; i < nr_range; i++)
ret = kernel_physical_mapping_init(mr[i].start, mr[i].end,
mr[i].page_size_mask);
#endif

#ifdef CONFIG_X86_32
early_ioremap_page_table_range_init();

load_cr3(swapper_pg_dir);
#endif

#ifdef CONFIG_X86_64
if (!after_bootmem)
mmu_cr4_features = read_cr4();
#endif
__flush_tlb_all();

if (!after_bootmem && table_end > table_start)
reserve_early(table_start << PAGE_SHIFT,
table_end << PAGE_SHIFT, "PGTABLE");

if (!after_bootmem)
early_memtest(start, end);

return ret >> PAGE_SHIFT;
}


/*
* devmem_is_allowed() checks to see if /dev/mem access to a certain address
Expand Down
Loading

0 comments on commit f765090

Please sign in to comment.