/*
* Copyright 2005, Paul Mackerras, IBM Corporation.
* Copyright 2009, Benjamin Herrenschmidt, IBM Corporation.
* Copyright 2015-2016, Aneesh Kumar K.V, IBM Corporation.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*/
#include <linux/sched.h>
#include <asm/pgalloc.h>
#include <asm/tlb.h>
#include "mmu_decl.h"
#ifdef CONFIG_SPARSEMEM_VMEMMAP
/*
* On hash-based CPUs, the vmemmap is bolted in the hash table.
*
*/
int __meminit vmemmap_create_mapping(unsigned long start,
unsigned long page_size,
unsigned long phys)
{
int rc = htab_bolt_mapping(start, start + page_size, phys,
pgprot_val(PAGE_KERNEL),
mmu_vmemmap_psize, mmu_kernel_ssize);
if (rc < 0) {
int rc2 = htab_remove_mapping(start, start + page_size,
mmu_vmemmap_psize,
mmu_kernel_ssize);
BUG_ON(rc2 && (rc2 != -ENOENT));
}
return rc;
}
#ifdef CONFIG_MEMORY_HOTPLUG
void vmemmap_remove_mapping(unsigned long start,
unsigned long page_size)
{
int rc = htab_remove_mapping(start, start + page_size,
mmu_vmemmap_psize,
mmu_kernel_ssize);
BUG_ON((rc < 0) && (rc != -ENOENT));
WARN_ON(rc == -ENOENT);
}
#endif
#endif /* CONFIG_SPARSEMEM_VMEMMAP */
/*
* map_kernel_page currently only called by __ioremap
* map_kernel_page adds an entry to the ioremap page table
* and adds an entry to the HPT, possibly bolting it
*/
int map_kernel_page(unsigned long ea, unsigned long pa, unsigned long flags)
{
pgd_t *pgdp;
pud_t *pudp;
pmd_t *pmdp;
pte_t *ptep;
if (slab_is_available()) {
pgdp = pgd_offset_k(ea);
pudp = pud_alloc(&init_mm, pgdp, ea);
if (!pudp)
return -ENOMEM;
pmdp = pmd_alloc(&init_mm, pudp, ea);
if (!pmdp)
return -ENOMEM;
ptep = pte_alloc_kernel(pmdp, ea);
if (!ptep)
return -ENOMEM;
set_pte_at(&init_mm, ea, ptep, pfn_pte(pa >> PAGE_SHIFT,
__pgprot(flags)));
} else {
/*
* If the mm subsystem is not fully up, we cannot create a
* linux page table entry for this mapping. Simply bolt an
* entry in the hardware page table.
*
*/
if (htab_bolt_mapping(ea, ea + PAGE_SIZE, pa, flags,
mmu_io_psize, mmu_kernel_ssize)) {
printk(KERN_ERR "Failed to do bolted mapping IO "
"memory at %016lx !\n", pa);
return -ENOMEM;
}
}
smp_wmb();
return 0;
}
