m68k: mm: Move the pointer table allocator to motorola.c

Only the Motorola MMU makes use of this allocator, it is a waste of
.text to include it for Sun3/ColdFire. Also, this is going to avoid
build issues when we're going to make it more Motorola specific.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Will Deacon <will@kernel.org>
Acked-by: Greg Ungerer <gerg@linux-m68k.org>
Tested-by: Michael Schmitz <schmitzmic@gmail.com>
Tested-by: Greg Ungerer <gerg@linux-m68k.org>
Link: https://lore.kernel.org/r/20200131125403.654652162@infradead.org
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
This commit is contained in:
Peter Zijlstra 2020-01-31 13:45:35 +01:00 committed by Geert Uytterhoeven
parent 13076a29d5
commit 5ad272abee
2 changed files with 102 additions and 102 deletions

View file

@ -22,108 +22,6 @@
#include <asm/machdep.h>
/* ++andreas: {get,free}_pointer_table rewritten to use unused fields from
struct page instead of separately kmalloced struct. Stolen from
arch/sparc/mm/srmmu.c ... */
typedef struct list_head ptable_desc;
static LIST_HEAD(ptable_list);
#define PD_PTABLE(page) ((ptable_desc *)&(virt_to_page(page)->lru))
#define PD_PAGE(ptable) (list_entry(ptable, struct page, lru))
#define PD_MARKBITS(dp) (*(unsigned char *)&PD_PAGE(dp)->index)
#define PTABLE_SIZE (PTRS_PER_PMD * sizeof(pmd_t))
void __init init_pointer_table(unsigned long ptable)
{
ptable_desc *dp;
unsigned long page = ptable & PAGE_MASK;
unsigned char mask = 1 << ((ptable - page)/PTABLE_SIZE);
dp = PD_PTABLE(page);
if (!(PD_MARKBITS(dp) & mask)) {
PD_MARKBITS(dp) = 0xff;
list_add(dp, &ptable_list);
}
PD_MARKBITS(dp) &= ~mask;
pr_debug("init_pointer_table: %lx, %x\n", ptable, PD_MARKBITS(dp));
/* unreserve the page so it's possible to free that page */
__ClearPageReserved(PD_PAGE(dp));
init_page_count(PD_PAGE(dp));
return;
}
pmd_t *get_pointer_table (void)
{
ptable_desc *dp = ptable_list.next;
unsigned char mask = PD_MARKBITS (dp);
unsigned char tmp;
unsigned int off;
/*
* For a pointer table for a user process address space, a
* table is taken from a page allocated for the purpose. Each
* page can hold 8 pointer tables. The page is remapped in
* virtual address space to be noncacheable.
*/
if (mask == 0) {
void *page;
ptable_desc *new;
if (!(page = (void *)get_zeroed_page(GFP_KERNEL)))
return NULL;
mmu_page_ctor(page);
new = PD_PTABLE(page);
PD_MARKBITS(new) = 0xfe;
list_add_tail(new, dp);
return (pmd_t *)page;
}
for (tmp = 1, off = 0; (mask & tmp) == 0; tmp <<= 1, off += PTABLE_SIZE)
;
PD_MARKBITS(dp) = mask & ~tmp;
if (!PD_MARKBITS(dp)) {
/* move to end of list */
list_move_tail(dp, &ptable_list);
}
return (pmd_t *) (page_address(PD_PAGE(dp)) + off);
}
int free_pointer_table (pmd_t *ptable)
{
ptable_desc *dp;
unsigned long page = (unsigned long)ptable & PAGE_MASK;
unsigned char mask = 1 << (((unsigned long)ptable - page)/PTABLE_SIZE);
dp = PD_PTABLE(page);
if (PD_MARKBITS (dp) & mask)
panic ("table already free!");
PD_MARKBITS (dp) |= mask;
if (PD_MARKBITS(dp) == 0xff) {
/* all tables in page are free, free page */
list_del(dp);
mmu_page_dtor((void *)page);
free_page (page);
return 1;
} else if (ptable_list.next != dp) {
/*
* move this descriptor to the front of the list, since
* it has one or more free tables.
*/
list_move(dp, &ptable_list);
}
return 0;
}
/* invalidate page in both caches */
static inline void clear040(unsigned long paddr)
{

View file

@ -67,6 +67,108 @@ void mmu_page_dtor(void *page)
cache_page(page);
}
/* ++andreas: {get,free}_pointer_table rewritten to use unused fields from
struct page instead of separately kmalloced struct. Stolen from
arch/sparc/mm/srmmu.c ... */
typedef struct list_head ptable_desc;
static LIST_HEAD(ptable_list);
#define PD_PTABLE(page) ((ptable_desc *)&(virt_to_page(page)->lru))
#define PD_PAGE(ptable) (list_entry(ptable, struct page, lru))
#define PD_MARKBITS(dp) (*(unsigned char *)&PD_PAGE(dp)->index)
#define PTABLE_SIZE (PTRS_PER_PMD * sizeof(pmd_t))
void __init init_pointer_table(unsigned long ptable)
{
ptable_desc *dp;
unsigned long page = ptable & PAGE_MASK;
unsigned char mask = 1 << ((ptable - page)/PTABLE_SIZE);
dp = PD_PTABLE(page);
if (!(PD_MARKBITS(dp) & mask)) {
PD_MARKBITS(dp) = 0xff;
list_add(dp, &ptable_list);
}
PD_MARKBITS(dp) &= ~mask;
pr_debug("init_pointer_table: %lx, %x\n", ptable, PD_MARKBITS(dp));
/* unreserve the page so it's possible to free that page */
__ClearPageReserved(PD_PAGE(dp));
init_page_count(PD_PAGE(dp));
return;
}
pmd_t *get_pointer_table (void)
{
ptable_desc *dp = ptable_list.next;
unsigned char mask = PD_MARKBITS (dp);
unsigned char tmp;
unsigned int off;
/*
* For a pointer table for a user process address space, a
* table is taken from a page allocated for the purpose. Each
* page can hold 8 pointer tables. The page is remapped in
* virtual address space to be noncacheable.
*/
if (mask == 0) {
void *page;
ptable_desc *new;
if (!(page = (void *)get_zeroed_page(GFP_KERNEL)))
return NULL;
mmu_page_ctor(page);
new = PD_PTABLE(page);
PD_MARKBITS(new) = 0xfe;
list_add_tail(new, dp);
return (pmd_t *)page;
}
for (tmp = 1, off = 0; (mask & tmp) == 0; tmp <<= 1, off += PTABLE_SIZE)
;
PD_MARKBITS(dp) = mask & ~tmp;
if (!PD_MARKBITS(dp)) {
/* move to end of list */
list_move_tail(dp, &ptable_list);
}
return (pmd_t *) (page_address(PD_PAGE(dp)) + off);
}
int free_pointer_table (pmd_t *ptable)
{
ptable_desc *dp;
unsigned long page = (unsigned long)ptable & PAGE_MASK;
unsigned char mask = 1 << (((unsigned long)ptable - page)/PTABLE_SIZE);
dp = PD_PTABLE(page);
if (PD_MARKBITS (dp) & mask)
panic ("table already free!");
PD_MARKBITS (dp) |= mask;
if (PD_MARKBITS(dp) == 0xff) {
/* all tables in page are free, free page */
list_del(dp);
mmu_page_dtor((void *)page);
free_page (page);
return 1;
} else if (ptable_list.next != dp) {
/*
* move this descriptor to the front of the list, since
* it has one or more free tables.
*/
list_move(dp, &ptable_list);
}
return 0;
}
/* size of memory already mapped in head.S */
extern __initdata unsigned long m68k_init_mapped_size;