[linux-2.6-block.git] / arch / x86 / mm / pgtable_32.c

// SPDX-License-Identifier: GPL-2.0
#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/mm.h>
#include <linux/nmi.h>
#include <linux/swap.h>
#include <linux/smp.h>
#include <linux/highmem.h>
#include <linux/pagemap.h>
#include <linux/spinlock.h>

#include <asm/cpu_entry_area.h>
#include <asm/pgtable.h>
#include <asm/pgalloc.h>
#include <asm/fixmap.h>
#include <asm/e820/api.h>
#include <asm/tlb.h>
#include <asm/tlbflush.h>
#include <asm/io.h>

unsigned int __VMALLOC_RESERVE = 128 << 20;

/*
 * Associate a virtual page frame with a given physical page frame 
 * and protection flags for that frame.
 */ 
void set_pte_vaddr(unsigned long vaddr, pte_t pteval)
{
	pgd_t *pgd;
	p4d_t *p4d;
	pud_t *pud;
	pmd_t *pmd;
	pte_t *pte;

	pgd = swapper_pg_dir + pgd_index(vaddr);
	if (pgd_none(*pgd)) {
		BUG();
		return;
	}
	p4d = p4d_offset(pgd, vaddr);
	if (p4d_none(*p4d)) {
		BUG();
		return;
	}
	pud = pud_offset(p4d, vaddr);
	if (pud_none(*pud)) {
		BUG();
		return;
	}
	pmd = pmd_offset(pud, vaddr);
	if (pmd_none(*pmd)) {
		BUG();
		return;
	}
	pte = pte_offset_kernel(pmd, vaddr);
	if (!pte_none(pteval))
		set_pte_at(&init_mm, vaddr, pte, pteval);
	else
		pte_clear(&init_mm, vaddr, pte);

	/*
	 * It's enough to flush this one mapping.
	 * (PGE mappings get flushed as well)
	 */
	__flush_tlb_one_kernel(vaddr);
}

unsigned long __FIXADDR_TOP = 0xfffff000;
EXPORT_SYMBOL(__FIXADDR_TOP);

/*
 * vmalloc=size forces the vmalloc area to be exactly 'size'
 * bytes. This can be used to increase (or decrease) the
 * vmalloc area - the default is 128m.
 */
static int __init parse_vmalloc(char *arg)
{
	if (!arg)
		return -EINVAL;

	/* Add VMALLOC_OFFSET to the parsed value due to vm area guard hole*/
	__VMALLOC_RESERVE = memparse(arg, &arg) + VMALLOC_OFFSET;
	return 0;
}
early_param("vmalloc", parse_vmalloc);

/*
 * reservetop=size reserves a hole at the top of the kernel address space which
 * a hypervisor can load into later.  Needed for dynamically loaded hypervisors,
 * so relocating the fixmap can be done before paging initialization.
 */
static int __init parse_reservetop(char *arg)
{
	unsigned long address;

	if (!arg)
		return -EINVAL;

	address = memparse(arg, &arg);
	reserve_top_address(address);
	early_ioremap_init();
	return 0;
}
early_param("reservetop", parse_reservetop);
Commit	Line	Data
b2441318	1	// SPDX-License-Identifier: GPL-2.0
1da177e4 LT	2	#include <linux/sched.h>
	3	#include <linux/kernel.h>
	4	#include <linux/errno.h>
	5	#include <linux/mm.h>
27eb0b28	6	#include <linux/nmi.h>
1da177e4 LT	7	#include <linux/swap.h>
	8	#include <linux/smp.h>
	9	#include <linux/highmem.h>
1da177e4 LT	10	#include <linux/pagemap.h>
	11	#include <linux/spinlock.h>
	12
92a0f81d	13	#include <asm/cpu_entry_area.h>
1da177e4 LT	14	#include <asm/pgtable.h>
	15	#include <asm/pgalloc.h>
	16	#include <asm/fixmap.h>
66441bd3	17	#include <asm/e820/api.h>
1da177e4 LT	18	#include <asm/tlb.h>
1da177e4 LT	19	#include <asm/tlbflush.h>
56f0e74c	20	#include <asm/io.h>
1da177e4	21
2b688dfd PE	22	unsigned int __VMALLOC_RESERVE = 128 << 20;
2b688dfd PE	23
1da177e4 LT	24	/*
	25	* Associate a virtual page frame with a given physical page frame
	26	* and protection flags for that frame.
	27	*/
d494a961	28	void set_pte_vaddr(unsigned long vaddr, pte_t pteval)
1da177e4 LT	29	{
1da177e4 LT	30	pgd_t *pgd;
e0c4f675	31	p4d_t *p4d;
1da177e4 LT	32	pud_t *pud;
	33	pmd_t *pmd;
	34	pte_t *pte;
	35
	36	pgd = swapper_pg_dir + pgd_index(vaddr);
	37	if (pgd_none(*pgd)) {
	38	BUG();
	39	return;
	40	}
e0c4f675 KS	41	p4d = p4d_offset(pgd, vaddr);
	42	if (p4d_none(*p4d)) {
	43	BUG();
	44	return;
	45	}
	46	pud = pud_offset(p4d, vaddr);
1da177e4 LT	47	if (pud_none(*pud)) {
	48	BUG();
	49	return;
	50	}
	51	pmd = pmd_offset(pud, vaddr);
	52	if (pmd_none(*pmd)) {
	53	BUG();
	54	return;
	55	}
	56	pte = pte_offset_kernel(pmd, vaddr);
dcb32d99	57	if (!pte_none(pteval))
b40c7579	58	set_pte_at(&init_mm, vaddr, pte, pteval);
b0bfece4 JB	59	else
b0bfece4 JB	60	pte_clear(&init_mm, vaddr, pte);
1da177e4 LT	61
	62	/*
	63	* It's enough to flush this one mapping.
	64	* (PGE mappings get flushed as well)
1da177e4	65	*/
1299ef1d	66	__flush_tlb_one_kernel(vaddr);
1da177e4 LT	67	}
1da177e4 LT	68
052e7994 JF	69	unsigned long __FIXADDR_TOP = 0xfffff000;
052e7994 JF	70	EXPORT_SYMBOL(__FIXADDR_TOP);
052e7994	71
bef1568d YL	72	/*
	73	* vmalloc=size forces the vmalloc area to be exactly 'size'
	74	* bytes. This can be used to increase (or decrease) the
	75	* vmalloc area - the default is 128m.
	76	*/
	77	static int __init parse_vmalloc(char *arg)
	78	{
	79	if (!arg)
	80	return -EINVAL;
	81
e621bd18 DY	82	/* Add VMALLOC_OFFSET to the parsed value due to vm area guard hole*/
e621bd18 DY	83	__VMALLOC_RESERVE = memparse(arg, &arg) + VMALLOC_OFFSET;
bef1568d YL	84	return 0;
	85	}
	86	early_param("vmalloc", parse_vmalloc);
	87
	88	/*
	89	* reservetop=size reserves a hole at the top of the kernel address space which
	90	* a hypervisor can load into later. Needed for dynamically loaded hypervisors,
	91	* so relocating the fixmap can be done before paging initialization.
	92	*/
	93	static int __init parse_reservetop(char *arg)
	94	{
	95	unsigned long address;
	96
	97	if (!arg)
	98	return -EINVAL;
	99
	100	address = memparse(arg, &arg);
	101	reserve_top_address(address);
5b7c73e0	102	early_ioremap_init();
bef1568d YL	103	return 0;
	104	}
	105	early_param("reservetop", parse_reservetop);