[S390] Dont check for pfn_valid() in uaccess_pt.c

pfn_valid() actually checks for a valid struct page and not for a
valid pfn. Using xip mappings w/o struct pages, this will result in
-EFAULT returned by the (page table walk) user copy functions,
even though there is valid memory. Those user copy functions don't
need a struct page, so this patch just removes the pfn_valid() check.

Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

diff --git a/arch/s390/lib/uaccess_pt.c b/arch/s390/lib/uaccess_pt.c
index d66215b0fde9d8d932cd31a43b3dee2e283b3a4a..b0b84c35b0ade7f23c464c6ee848183b63827469 100644 (file)
--- a/arch/s390/lib/uaccess_pt.c
+++ b/arch/s390/lib/uaccess_pt.c
@@ -119,8 +119,6 @@ retry:
                        goto fault;
 
                pfn = pte_pfn(*pte);
-               if (!pfn_valid(pfn))
-                       goto out;
 
                offset = uaddr & (PAGE_SIZE - 1);
                size = min(n - done, PAGE_SIZE - offset);
@@ -135,7 +133,6 @@ retry:
                done += size;
                uaddr += size;
        } while (done < n);
-out:
        spin_unlock(&mm->page_table_lock);
        return n - done;
 fault:
@@ -163,9 +160,6 @@ retry:
                goto fault;
 
        pfn = pte_pfn(*pte);
-       if (!pfn_valid(pfn))
-               goto out;
-
        ret = (pfn << PAGE_SHIFT) + (uaddr & (PAGE_SIZE - 1));
 out:
        return ret;
@@ -244,11 +238,6 @@ retry:
                        goto fault;
 
                pfn = pte_pfn(*pte);
-               if (!pfn_valid(pfn)) {
-                       done = -1;
-                       goto out;
-               }
-
                offset = uaddr & (PAGE_SIZE-1);
                addr = (char *)(pfn << PAGE_SHIFT) + offset;
                len = min(count - done, PAGE_SIZE - offset);
@@ -256,7 +245,6 @@ retry:
                done += len_str;
                uaddr += len_str;
        } while ((len_str == len) && (done < count));
-out:
        spin_unlock(&mm->page_table_lock);
        return done + 1;
 fault:
@@ -325,12 +313,7 @@ retry:
                }
 
                pfn_from = pte_pfn(*pte_from);
-               if (!pfn_valid(pfn_from))
-                       goto out;
                pfn_to = pte_pfn(*pte_to);
-               if (!pfn_valid(pfn_to))
-                       goto out;
-
                offset_from = uaddr_from & (PAGE_SIZE-1);
                offset_to = uaddr_from & (PAGE_SIZE-1);
                offset_max = max(offset_from, offset_to);
@@ -342,7 +325,6 @@ retry:
                uaddr_from += size;
                uaddr_to += size;
        } while (done < n);
-out:
        spin_unlock(&mm->page_table_lock);
        return n - done;
 fault: