kernel-ark/arch/blackfin/mm/init.c
Sonic Zhang 46284cd6bf Blackfin: merge kernel init memory back into main memory region
If the kernel's init section is merged back into the main memory region
during boot (which it should since that is how we've laid out the kernel
linker map), we want to make sure that these aren't counted as independent
regions.  Otherwise, if a large mapping is attempted which starts in the
init region and extends into the main memory region, the access_ok func
will deny it.  This leads to weird messages during runtime like "unable
to map xxx library" from the ldso but upon running the application again,
everything works fine.

So if the address of the end of the init region is the same as the start
of the main memory region, simply enlarge the memory region to include
the init region.

Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2010-10-22 04:02:01 -04:00

166 lines
4.6 KiB
C

/*
* Copyright 2004-2009 Analog Devices Inc.
*
* Licensed under the GPL-2 or later.
*/
#include <linux/gfp.h>
#include <linux/swap.h>
#include <linux/bootmem.h>
#include <linux/uaccess.h>
#include <asm/bfin-global.h>
#include <asm/pda.h>
#include <asm/cplbinit.h>
#include <asm/early_printk.h>
#include "blackfin_sram.h"
/*
* ZERO_PAGE is a special page that is used for zero-initialized data and COW.
* Let the bss do its zero-init magic so we don't have to do it ourselves.
*/
char empty_zero_page[PAGE_SIZE] __attribute__((aligned(PAGE_SIZE)));
EXPORT_SYMBOL(empty_zero_page);
#ifndef CONFIG_EXCEPTION_L1_SCRATCH
#if defined CONFIG_SYSCALL_TAB_L1
__attribute__((l1_data))
#endif
static unsigned long exception_stack[NR_CPUS][1024];
#endif
struct blackfin_pda cpu_pda[NR_CPUS];
EXPORT_SYMBOL(cpu_pda);
/*
* paging_init() continues the virtual memory environment setup which
* was begun by the code in arch/head.S.
* The parameters are pointers to where to stick the starting and ending
* addresses of available kernel virtual memory.
*/
void __init paging_init(void)
{
/*
* make sure start_mem is page aligned, otherwise bootmem and
* page_alloc get different views of the world
*/
unsigned long end_mem = memory_end & PAGE_MASK;
unsigned long zones_size[MAX_NR_ZONES] = {
[0] = 0,
[ZONE_DMA] = (end_mem - PAGE_OFFSET) >> PAGE_SHIFT,
[ZONE_NORMAL] = 0,
#ifdef CONFIG_HIGHMEM
[ZONE_HIGHMEM] = 0,
#endif
};
/* Set up SFC/DFC registers (user data space) */
set_fs(KERNEL_DS);
pr_debug("free_area_init -> start_mem is %#lx virtual_end is %#lx\n",
PAGE_ALIGN(memory_start), end_mem);
free_area_init(zones_size);
}
asmlinkage void __init init_pda(void)
{
unsigned int cpu = raw_smp_processor_id();
early_shadow_stamp();
/* Initialize the PDA fields holding references to other parts
of the memory. The content of such memory is still
undefined at the time of the call, we are only setting up
valid pointers to it. */
memset(&cpu_pda[cpu], 0, sizeof(cpu_pda[cpu]));
cpu_pda[0].next = &cpu_pda[1];
cpu_pda[1].next = &cpu_pda[0];
#ifdef CONFIG_EXCEPTION_L1_SCRATCH
cpu_pda[cpu].ex_stack = (unsigned long *)(L1_SCRATCH_START + \
L1_SCRATCH_LENGTH);
#else
cpu_pda[cpu].ex_stack = exception_stack[cpu + 1];
#endif
#ifdef CONFIG_SMP
cpu_pda[cpu].imask = 0x1f;
#endif
}
void __init mem_init(void)
{
unsigned int codek = 0, datak = 0, initk = 0;
unsigned int reservedpages = 0, freepages = 0;
unsigned long tmp;
unsigned long start_mem = memory_start;
unsigned long end_mem = memory_end;
end_mem &= PAGE_MASK;
high_memory = (void *)end_mem;
start_mem = PAGE_ALIGN(start_mem);
max_mapnr = num_physpages = MAP_NR(high_memory);
printk(KERN_DEBUG "Kernel managed physical pages: %lu\n", num_physpages);
/* This will put all memory onto the freelists. */
totalram_pages = free_all_bootmem();
reservedpages = 0;
for (tmp = 0; tmp < max_mapnr; tmp++)
if (PageReserved(pfn_to_page(tmp)))
reservedpages++;
freepages = max_mapnr - reservedpages;
/* do not count in kernel image between _rambase and _ramstart */
reservedpages -= (_ramstart - _rambase) >> PAGE_SHIFT;
#if (defined(CONFIG_BFIN_EXTMEM_ICACHEABLE) && ANOMALY_05000263)
reservedpages += (_ramend - memory_end - DMA_UNCACHED_REGION) >> PAGE_SHIFT;
#endif
codek = (_etext - _stext) >> 10;
initk = (__init_end - __init_begin) >> 10;
datak = ((_ramstart - _rambase) >> 10) - codek - initk;
printk(KERN_INFO
"Memory available: %luk/%luk RAM, "
"(%uk init code, %uk kernel code, %uk data, %uk dma, %uk reserved)\n",
(unsigned long) freepages << (PAGE_SHIFT-10), _ramend >> 10,
initk, codek, datak, DMA_UNCACHED_REGION >> 10, (reservedpages << (PAGE_SHIFT-10)));
}
static void __init free_init_pages(const char *what, unsigned long begin, unsigned long end)
{
unsigned long addr;
/* next to check that the page we free is not a partial page */
for (addr = begin; addr + PAGE_SIZE <= end; addr += PAGE_SIZE) {
ClearPageReserved(virt_to_page(addr));
init_page_count(virt_to_page(addr));
free_page(addr);
totalram_pages++;
}
printk(KERN_INFO "Freeing %s: %ldk freed\n", what, (end - begin) >> 10);
}
#ifdef CONFIG_BLK_DEV_INITRD
void __init free_initrd_mem(unsigned long start, unsigned long end)
{
#ifndef CONFIG_MPU
free_init_pages("initrd memory", start, end);
#endif
}
#endif
void __init_refok free_initmem(void)
{
#if defined CONFIG_RAMKERNEL && !defined CONFIG_MPU
free_init_pages("unused kernel memory",
(unsigned long)(&__init_begin),
(unsigned long)(&__init_end));
if (memory_start == (unsigned long)(&__init_end))
memory_start = (unsigned long)(&__init_begin);
#endif
}