arch/um: fix kunmap_atomic() call in skas/uaccess.c

[pandora-kernel.git] / arch / um / kernel / skas / uaccess.c

diff --git a/arch/um/kernel/skas/uaccess.c b/arch/um/kernel/skas/uaccess.c
index 1d8b119..6966342 100644 (file)
--- a/arch/um/kernel/skas/uaccess.c
+++ b/arch/um/kernel/skas/uaccess.c
@@ -3,128 +3,130 @@
  * Licensed under the GPL
  */
 
-#include "linux/err.h"
-#include "linux/highmem.h"
-#include "linux/mm.h"
-#include "asm/current.h"
-#include "asm/page.h"
-#include "asm/pgtable.h"
+#include <linux/err.h>
+#include <linux/highmem.h>
+#include <linux/mm.h>
+#include <linux/sched.h>
+#include <asm/current.h>
+#include <asm/page.h>
+#include <asm/pgtable.h>
 #include "kern_util.h"
 #include "os.h"
 
-extern void *um_virt_to_phys(struct task_struct *task, unsigned long addr,
-                            pte_t *pte_out);
-
-static unsigned long maybe_map(unsigned long virt, int is_write)
+pte_t *virt_to_pte(struct mm_struct *mm, unsigned long addr)
 {
-       pte_t pte;
-       int err;
+       pgd_t *pgd;
+       pud_t *pud;
+       pmd_t *pmd;
+
+       if (mm == NULL)
+               return NULL;
+
+       pgd = pgd_offset(mm, addr);
+       if (!pgd_present(*pgd))
+               return NULL;
+
+       pud = pud_offset(pgd, addr);
+       if (!pud_present(*pud))
+               return NULL;
 
-       void *phys = um_virt_to_phys(current, virt, &pte);
-       int dummy_code;
+       pmd = pmd_offset(pud, addr);
+       if (!pmd_present(*pmd))
+               return NULL;
+
+       return pte_offset_kernel(pmd, addr);
+}
+
+static pte_t *maybe_map(unsigned long virt, int is_write)
+{
+       pte_t *pte = virt_to_pte(current->mm, virt);
+       int err, dummy_code;
 
-       if (IS_ERR(phys) || (is_write && !pte_write(pte))) {
+       if ((pte == NULL) || !pte_present(*pte) ||
+           (is_write && !pte_write(*pte))) {
                err = handle_page_fault(virt, 0, is_write, 1, &dummy_code);
                if (err)
-                       return -1UL;
-               phys = um_virt_to_phys(current, virt, NULL);
+                       return NULL;
+               pte = virt_to_pte(current->mm, virt);
        }
-       if (IS_ERR(phys))
-               phys = (void *) -1;
+       if (!pte_present(*pte))
+               pte = NULL;
 
-       return (unsigned long) phys;
+       return pte;
 }
 
 static int do_op_one_page(unsigned long addr, int len, int is_write,
                 int (*op)(unsigned long addr, int len, void *arg), void *arg)
 {
+       jmp_buf buf;
        struct page *page;
-       int n;
+       pte_t *pte;
+       int n, faulted;
 
-       addr = maybe_map(addr, is_write);
-       if (addr == -1UL)
+       pte = maybe_map(addr, is_write);
+       if (pte == NULL)
                return -1;
 
-       page = phys_to_page(addr);
+       page = pte_page(*pte);
        addr = (unsigned long) kmap_atomic(page, KM_UML_USERCOPY) +
                (addr & ~PAGE_MASK);
 
-       n = (*op)(addr, len, arg);
+       current->thread.fault_catcher = &buf;
+
+       faulted = UML_SETJMP(&buf);
+       if (faulted == 0)
+               n = (*op)(addr, len, arg);
+       else
+               n = -1;
+
+       current->thread.fault_catcher = NULL;
 
-       kunmap_atomic(page, KM_UML_USERCOPY);
+       kunmap_atomic((void *)addr, KM_UML_USERCOPY);
 
        return n;
 }
 
-static void do_buffer_op(void *jmpbuf, void *arg_ptr)
+static int buffer_op(unsigned long addr, int len, int is_write,
+                    int (*op)(unsigned long, int, void *), void *arg)
 {
-       va_list args;
-       unsigned long addr;
-       int len, is_write, size, remain, n;
-       int (*op)(unsigned long, int, void *);
-       void *arg;
-       int *res;
-
-       va_copy(args, *(va_list *)arg_ptr);
-       addr = va_arg(args, unsigned long);
-       len = va_arg(args, int);
-       is_write = va_arg(args, int);
-       op = va_arg(args, void *);
-       arg = va_arg(args, void *);
-       res = va_arg(args, int *);
-       va_end(args);
+       int size, remain, n;
+
        size = min(PAGE_ALIGN(addr) - addr, (unsigned long) len);
        remain = len;
 
-       current->thread.fault_catcher = jmpbuf;
        n = do_op_one_page(addr, size, is_write, op, arg);
        if (n != 0) {
-               *res = (n < 0 ? remain : 0);
+               remain = (n < 0 ? remain : 0);
                goto out;
        }
 
        addr += size;
        remain -= size;
-       if (remain == 0) {
-               *res = 0;
+       if (remain == 0)
                goto out;
-       }
 
-       while(addr < ((addr + remain) & PAGE_MASK)) {
+       while (addr < ((addr + remain) & PAGE_MASK)) {
                n = do_op_one_page(addr, PAGE_SIZE, is_write, op, arg);
                if (n != 0) {
-                       *res = (n < 0 ? remain : 0);
+                       remain = (n < 0 ? remain : 0);
                        goto out;
                }
 
                addr += PAGE_SIZE;
                remain -= PAGE_SIZE;
        }
-       if (remain == 0) {
-               *res = 0;
+       if (remain == 0)
                goto out;
-       }
 
        n = do_op_one_page(addr, remain, is_write, op, arg);
-       if (n != 0)
-               *res = (n < 0 ? remain : 0);
-       else *res = 0;
- out:
-       current->thread.fault_catcher = NULL;
-}
-
-static int buffer_op(unsigned long addr, int len, int is_write,
-                    int (*op)(unsigned long addr, int len, void *arg),
-                    void *arg)
-{
-       int faulted, res;
-
-       faulted = setjmp_wrapper(do_buffer_op, addr, len, is_write, op, arg,
-                                &res);
-       if (!faulted)
-               return res;
+       if (n != 0) {
+               remain = (n < 0 ? remain : 0);
+               goto out;
+       }
 
-       return addr + len - (unsigned long) current->thread.fault_addr;
+       return 0;
+ out:
+       return remain;
 }
 
 static int copy_chunk_from_user(unsigned long from, int len, void *arg)