clarify get_user_pages() prototype

[GitHub/mt8127/android_kernel_alcatel_ttab.git] / mm / memory.c

diff --git a/mm/memory.c b/mm/memory.c
index 98bcb90d5957010ada3218c06117cc797aa81813..65216194eb8daec69843ef672d73725eeb37e0ca 100644 (file)
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -1207,8 +1207,8 @@ static inline int use_zero_page(struct vm_area_struct *vma)
 
 
 int __get_user_pages(struct task_struct *tsk, struct mm_struct *mm,
-                    unsigned long start, int len, int flags,
-               struct page **pages, struct vm_area_struct **vmas)
+                    unsigned long start, int nr_pages, int flags,
+                    struct page **pages, struct vm_area_struct **vmas)
 {
        int i;
        unsigned int vm_flags = 0;
@@ -1217,7 +1217,7 @@ int __get_user_pages(struct task_struct *tsk, struct mm_struct *mm,
        int ignore = !!(flags & GUP_FLAGS_IGNORE_VMA_PERMISSIONS);
        int ignore_sigkill = !!(flags & GUP_FLAGS_IGNORE_SIGKILL);
 
-       if (len <= 0)
+       if (nr_pages <= 0)
                return 0;
        /* 
         * Require read or write permissions.
@@ -1269,7 +1269,7 @@ int __get_user_pages(struct task_struct *tsk, struct mm_struct *mm,
                                vmas[i] = gate_vma;
                        i++;
                        start += PAGE_SIZE;
-                       len--;
+                       nr_pages--;
                        continue;
                }
 
@@ -1280,7 +1280,7 @@ int __get_user_pages(struct task_struct *tsk, struct mm_struct *mm,
 
                if (is_vm_hugetlb_page(vma)) {
                        i = follow_hugetlb_page(mm, vma, pages, vmas,
-                                               &start, &len, i, write);
+                                               &start, &nr_pages, i, write);
                        continue;
                }
 
@@ -1311,8 +1311,10 @@ int __get_user_pages(struct task_struct *tsk, struct mm_struct *mm,
                        while (!(page = follow_page(vma, start, foll_flags))) {
                                int ret;
 
-                               /* FOLL_WRITE matches FAULT_FLAG_WRITE! */
-                               ret = handle_mm_fault(mm, vma, start, foll_flags & FOLL_WRITE);
+                               ret = handle_mm_fault(mm, vma, start,
+                                       (foll_flags & FOLL_WRITE) ?
+                                       FAULT_FLAG_WRITE : 0);
+
                                if (ret & VM_FAULT_ERROR) {
                                        if (ret & VM_FAULT_OOM)
                                                return i ? i : -ENOMEM;
@@ -1355,9 +1357,9 @@ int __get_user_pages(struct task_struct *tsk, struct mm_struct *mm,
                                vmas[i] = vma;
                        i++;
                        start += PAGE_SIZE;
-                       len--;
-               } while (len && start < vma->vm_end);
-       } while (len);
+                       nr_pages--;
+               } while (nr_pages && start < vma->vm_end);
+       } while (nr_pages);
        return i;
 }
 
@@ -1366,7 +1368,7 @@ int __get_user_pages(struct task_struct *tsk, struct mm_struct *mm,
  * @tsk:       task_struct of target task
  * @mm:                mm_struct of target mm
  * @start:     starting user address
- * @len:       number of pages from start to pin
+ * @nr_pages:  number of pages from start to pin
  * @write:     whether pages will be written to by the caller
  * @force:     whether to force write access even if user mapping is
  *             readonly. This will result in the page being COWed even
@@ -1378,7 +1380,7 @@ int __get_user_pages(struct task_struct *tsk, struct mm_struct *mm,
  *             Or NULL if the caller does not require them.
  *
  * Returns number of pages pinned. This may be fewer than the number
- * requested. If len is 0 or negative, returns 0. If no pages
+ * requested. If nr_pages is 0 or negative, returns 0. If no pages
  * were pinned, returns -errno. Each page returned must be released
  * with a put_page() call when it is finished with. vmas will only
  * remain valid while mmap_sem is held.
@@ -1412,7 +1414,7 @@ int __get_user_pages(struct task_struct *tsk, struct mm_struct *mm,
  * See also get_user_pages_fast, for performance critical applications.
  */
 int get_user_pages(struct task_struct *tsk, struct mm_struct *mm,
-               unsigned long start, int len, int write, int force,
+               unsigned long start, int nr_pages, int write, int force,
                struct page **pages, struct vm_area_struct **vmas)
 {
        int flags = 0;
@@ -1422,9 +1424,7 @@ int get_user_pages(struct task_struct *tsk, struct mm_struct *mm,
        if (force)
                flags |= GUP_FLAGS_FORCE;
 
-       return __get_user_pages(tsk, mm,
-                               start, len, flags,
-                               pages, vmas);
+       return __get_user_pages(tsk, mm, start, nr_pages, flags, pages, vmas);
 }
 
 EXPORT_SYMBOL(get_user_pages);
@@ -2517,7 +2517,7 @@ static int do_swap_page(struct mm_struct *mm, struct vm_area_struct *vma,
        delayacct_set_flag(DELAYACCT_PF_SWAPIN);
        page = lookup_swap_cache(entry);
        if (!page) {
-               grab_swap_token(); /* Contend for token _before_ read-in */
+               grab_swap_token(mm); /* Contend for token _before_ read-in */
                page = swapin_readahead(entry,
                                        GFP_HIGHUSER_MOVABLE, vma, address);
                if (!page) {