mirror of
https://mirrors.bfsu.edu.cn/git/linux.git
synced 2024-11-15 00:04:15 +08:00
2165009bdf
We need this at least for huge page detection for now, because powerpc needs the vm_area_struct to be able to determine whether a virtual address is referring to a huge page (its pmd_huge() doesn't work). It might also come in handy for some of the other users. Signed-off-by: Dave Hansen <dave@linux.vnet.ibm.com> Acked-by: Matt Mackall <mpm@selenic.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
138 lines
3.2 KiB
C
138 lines
3.2 KiB
C
#include <linux/mm.h>
|
|
#include <linux/highmem.h>
|
|
#include <linux/sched.h>
|
|
|
|
static int walk_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end,
|
|
struct mm_walk *walk)
|
|
{
|
|
pte_t *pte;
|
|
int err = 0;
|
|
|
|
pte = pte_offset_map(pmd, addr);
|
|
for (;;) {
|
|
err = walk->pte_entry(pte, addr, addr + PAGE_SIZE, walk);
|
|
if (err)
|
|
break;
|
|
addr += PAGE_SIZE;
|
|
if (addr == end)
|
|
break;
|
|
pte++;
|
|
}
|
|
|
|
pte_unmap(pte);
|
|
return err;
|
|
}
|
|
|
|
static int walk_pmd_range(pud_t *pud, unsigned long addr, unsigned long end,
|
|
struct mm_walk *walk)
|
|
{
|
|
pmd_t *pmd;
|
|
unsigned long next;
|
|
int err = 0;
|
|
|
|
pmd = pmd_offset(pud, addr);
|
|
do {
|
|
next = pmd_addr_end(addr, end);
|
|
if (pmd_none_or_clear_bad(pmd)) {
|
|
if (walk->pte_hole)
|
|
err = walk->pte_hole(addr, next, walk);
|
|
if (err)
|
|
break;
|
|
continue;
|
|
}
|
|
if (walk->pmd_entry)
|
|
err = walk->pmd_entry(pmd, addr, next, walk);
|
|
if (!err && walk->pte_entry)
|
|
err = walk_pte_range(pmd, addr, next, walk);
|
|
if (err)
|
|
break;
|
|
} while (pmd++, addr = next, addr != end);
|
|
|
|
return err;
|
|
}
|
|
|
|
static int walk_pud_range(pgd_t *pgd, unsigned long addr, unsigned long end,
|
|
struct mm_walk *walk)
|
|
{
|
|
pud_t *pud;
|
|
unsigned long next;
|
|
int err = 0;
|
|
|
|
pud = pud_offset(pgd, addr);
|
|
do {
|
|
next = pud_addr_end(addr, end);
|
|
if (pud_none_or_clear_bad(pud)) {
|
|
if (walk->pte_hole)
|
|
err = walk->pte_hole(addr, next, walk);
|
|
if (err)
|
|
break;
|
|
continue;
|
|
}
|
|
if (walk->pud_entry)
|
|
err = walk->pud_entry(pud, addr, next, walk);
|
|
if (!err && (walk->pmd_entry || walk->pte_entry))
|
|
err = walk_pmd_range(pud, addr, next, walk);
|
|
if (err)
|
|
break;
|
|
} while (pud++, addr = next, addr != end);
|
|
|
|
return err;
|
|
}
|
|
|
|
/**
|
|
* walk_page_range - walk a memory map's page tables with a callback
|
|
* @mm: memory map to walk
|
|
* @addr: starting address
|
|
* @end: ending address
|
|
* @walk: set of callbacks to invoke for each level of the tree
|
|
*
|
|
* Recursively walk the page table for the memory area in a VMA,
|
|
* calling supplied callbacks. Callbacks are called in-order (first
|
|
* PGD, first PUD, first PMD, first PTE, second PTE... second PMD,
|
|
* etc.). If lower-level callbacks are omitted, walking depth is reduced.
|
|
*
|
|
* Each callback receives an entry pointer and the start and end of the
|
|
* associated range, and a copy of the original mm_walk for access to
|
|
* the ->private or ->mm fields.
|
|
*
|
|
* No locks are taken, but the bottom level iterator will map PTE
|
|
* directories from highmem if necessary.
|
|
*
|
|
* If any callback returns a non-zero value, the walk is aborted and
|
|
* the return value is propagated back to the caller. Otherwise 0 is returned.
|
|
*/
|
|
int walk_page_range(unsigned long addr, unsigned long end,
|
|
struct mm_walk *walk)
|
|
{
|
|
pgd_t *pgd;
|
|
unsigned long next;
|
|
int err = 0;
|
|
|
|
if (addr >= end)
|
|
return err;
|
|
|
|
if (!walk->mm)
|
|
return -EINVAL;
|
|
|
|
pgd = pgd_offset(walk->mm, addr);
|
|
do {
|
|
next = pgd_addr_end(addr, end);
|
|
if (pgd_none_or_clear_bad(pgd)) {
|
|
if (walk->pte_hole)
|
|
err = walk->pte_hole(addr, next, walk);
|
|
if (err)
|
|
break;
|
|
continue;
|
|
}
|
|
if (walk->pgd_entry)
|
|
err = walk->pgd_entry(pgd, addr, next, walk);
|
|
if (!err &&
|
|
(walk->pud_entry || walk->pmd_entry || walk->pte_entry))
|
|
err = walk_pud_range(pgd, addr, next, walk);
|
|
if (err)
|
|
break;
|
|
} while (pgd++, addr = next, addr != end);
|
|
|
|
return err;
|
|
}
|