linux/arch/s390/include/asm/pgalloc.h
Martin Schwidefsky 527e30b41d KVM: s390/mm: use radix trees for guest to host mappings
Store the target address for the gmap segments in a radix tree
instead of using invalid segment table entries. gmap_translate
becomes a simple radix_tree_lookup, gmap_fault is split into the
address translation with gmap_translate and the part that does
the linking of the gmap shadow page table with the process page
table.
A second radix tree is used to keep the pointers to the segment
table entries for segments that are mapped in the guest address
space. On unmap of a segment the pointer is retrieved from the
radix tree and is used to carry out the segment invalidation in
the gmap shadow page table. As the radix tree can only store one
pointer, each host segment may only be mapped to exactly one
guest location.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2014-08-26 10:09:02 +02:00

157 lines
4.2 KiB
C

/*
* S390 version
* Copyright IBM Corp. 1999, 2000
* Author(s): Hartmut Penner (hp@de.ibm.com)
* Martin Schwidefsky (schwidefsky@de.ibm.com)
*
* Derived from "include/asm-i386/pgalloc.h"
* Copyright (C) 1994 Linus Torvalds
*/
#ifndef _S390_PGALLOC_H
#define _S390_PGALLOC_H
#include <linux/threads.h>
#include <linux/gfp.h>
#include <linux/mm.h>
unsigned long *crst_table_alloc(struct mm_struct *);
void crst_table_free(struct mm_struct *, unsigned long *);
unsigned long *page_table_alloc(struct mm_struct *);
void page_table_free(struct mm_struct *, unsigned long *);
void page_table_free_rcu(struct mmu_gather *, unsigned long *, unsigned long);
void page_table_reset_pgste(struct mm_struct *, unsigned long, unsigned long,
bool init_skey);
int set_guest_storage_key(struct mm_struct *mm, unsigned long addr,
unsigned long key, bool nq);
static inline void clear_table(unsigned long *s, unsigned long val, size_t n)
{
typedef struct { char _[n]; } addrtype;
*s = val;
n = (n / 256) - 1;
asm volatile(
#ifdef CONFIG_64BIT
" mvc 8(248,%0),0(%0)\n"
#else
" mvc 4(252,%0),0(%0)\n"
#endif
"0: mvc 256(256,%0),0(%0)\n"
" la %0,256(%0)\n"
" brct %1,0b\n"
: "+a" (s), "+d" (n), "=m" (*(addrtype *) s)
: "m" (*(addrtype *) s));
}
static inline void crst_table_init(unsigned long *crst, unsigned long entry)
{
clear_table(crst, entry, sizeof(unsigned long)*2048);
}
#ifndef CONFIG_64BIT
static inline unsigned long pgd_entry_type(struct mm_struct *mm)
{
return _SEGMENT_ENTRY_EMPTY;
}
#define pud_alloc_one(mm,address) ({ BUG(); ((pud_t *)2); })
#define pud_free(mm, x) do { } while (0)
#define pmd_alloc_one(mm,address) ({ BUG(); ((pmd_t *)2); })
#define pmd_free(mm, x) do { } while (0)
#define pgd_populate(mm, pgd, pud) BUG()
#define pud_populate(mm, pud, pmd) BUG()
#else /* CONFIG_64BIT */
static inline unsigned long pgd_entry_type(struct mm_struct *mm)
{
if (mm->context.asce_limit <= (1UL << 31))
return _SEGMENT_ENTRY_EMPTY;
if (mm->context.asce_limit <= (1UL << 42))
return _REGION3_ENTRY_EMPTY;
return _REGION2_ENTRY_EMPTY;
}
int crst_table_upgrade(struct mm_struct *, unsigned long limit);
void crst_table_downgrade(struct mm_struct *, unsigned long limit);
static inline pud_t *pud_alloc_one(struct mm_struct *mm, unsigned long address)
{
unsigned long *table = crst_table_alloc(mm);
if (table)
crst_table_init(table, _REGION3_ENTRY_EMPTY);
return (pud_t *) table;
}
#define pud_free(mm, pud) crst_table_free(mm, (unsigned long *) pud)
static inline pmd_t *pmd_alloc_one(struct mm_struct *mm, unsigned long vmaddr)
{
unsigned long *table = crst_table_alloc(mm);
if (!table)
return NULL;
crst_table_init(table, _SEGMENT_ENTRY_EMPTY);
if (!pgtable_pmd_page_ctor(virt_to_page(table))) {
crst_table_free(mm, table);
return NULL;
}
return (pmd_t *) table;
}
static inline void pmd_free(struct mm_struct *mm, pmd_t *pmd)
{
pgtable_pmd_page_dtor(virt_to_page(pmd));
crst_table_free(mm, (unsigned long *) pmd);
}
static inline void pgd_populate(struct mm_struct *mm, pgd_t *pgd, pud_t *pud)
{
pgd_val(*pgd) = _REGION2_ENTRY | __pa(pud);
}
static inline void pud_populate(struct mm_struct *mm, pud_t *pud, pmd_t *pmd)
{
pud_val(*pud) = _REGION3_ENTRY | __pa(pmd);
}
#endif /* CONFIG_64BIT */
static inline pgd_t *pgd_alloc(struct mm_struct *mm)
{
spin_lock_init(&mm->context.list_lock);
INIT_LIST_HEAD(&mm->context.pgtable_list);
INIT_LIST_HEAD(&mm->context.gmap_list);
return (pgd_t *) crst_table_alloc(mm);
}
#define pgd_free(mm, pgd) crst_table_free(mm, (unsigned long *) pgd)
static inline void pmd_populate(struct mm_struct *mm,
pmd_t *pmd, pgtable_t pte)
{
pmd_val(*pmd) = _SEGMENT_ENTRY + __pa(pte);
}
#define pmd_populate_kernel(mm, pmd, pte) pmd_populate(mm, pmd, pte)
#define pmd_pgtable(pmd) \
(pgtable_t)(pmd_val(pmd) & -sizeof(pte_t)*PTRS_PER_PTE)
/*
* page table entry allocation/free routines.
*/
#define pte_alloc_one_kernel(mm, vmaddr) ((pte_t *) page_table_alloc(mm))
#define pte_alloc_one(mm, vmaddr) ((pte_t *) page_table_alloc(mm))
#define pte_free_kernel(mm, pte) page_table_free(mm, (unsigned long *) pte)
#define pte_free(mm, pte) page_table_free(mm, (unsigned long *) pte)
extern void rcu_table_freelist_finish(void);
#endif /* _S390_PGALLOC_H */