[PATCH] powerpc: fix for kexec ppc32

[pandora-kernel.git] / mm / memory.c

diff --git a/mm/memory.c b/mm/memory.c
index 430a72e..2bee1f2 100644 (file)
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -349,6 +349,11 @@ void print_bad_pte(struct vm_area_struct *vma, pte_t pte, unsigned long vaddr)
        dump_stack();
 }
 
+static inline int is_cow_mapping(unsigned int flags)
+{
+       return (flags & (VM_SHARED | VM_MAYWRITE)) == VM_MAYWRITE;
+}
+
 /*
  * This function gets the "struct page" associated with a pte.
  *
@@ -377,7 +382,7 @@ struct page *vm_normal_page(struct vm_area_struct *vma, unsigned long addr, pte_
                unsigned long off = (addr - vma->vm_start) >> PAGE_SHIFT;
                if (pfn == vma->vm_pgoff + off)
                        return NULL;
-               if (vma->vm_flags & VM_SHARED)
+               if (!is_cow_mapping(vma->vm_flags))
                        return NULL;
        }
 
@@ -439,7 +444,7 @@ copy_one_pte(struct mm_struct *dst_mm, struct mm_struct *src_mm,
         * If it's a COW mapping, write protect it both
         * in the parent and the child
         */
-       if ((vm_flags & (VM_SHARED | VM_MAYWRITE)) == VM_MAYWRITE) {
+       if (is_cow_mapping(vm_flags)) {
                ptep_set_wrprotect(src_mm, addr, src_pte);
                pte = *src_pte;
        }
@@ -569,7 +574,7 @@ int copy_page_range(struct mm_struct *dst_mm, struct mm_struct *src_mm,
         * readonly mappings. The tradeoff is that copy_page_range is more
         * efficient than faulting.
         */
-       if (!(vma->vm_flags & (VM_HUGETLB|VM_NONLINEAR|VM_PFNMAP))) {
+       if (!(vma->vm_flags & (VM_HUGETLB|VM_NONLINEAR|VM_PFNMAP|VM_INSERTPAGE))) {
                if (!vma->anon_vma)
                        return 0;
        }
@@ -1004,7 +1009,7 @@ int get_user_pages(struct task_struct *tsk, struct mm_struct *mm,
                        continue;
                }
 
-               if (!vma || (vma->vm_flags & VM_IO)
+               if (!vma || (vma->vm_flags & (VM_IO | VM_PFNMAP))
                                || !(vm_flags & vma->vm_flags))
                        return i ? : -EFAULT;
 
@@ -1223,6 +1228,7 @@ int vm_insert_page(struct vm_area_struct *vma, unsigned long addr, struct page *
                return -EFAULT;
        if (!page_count(page))
                return -EINVAL;
+       vma->vm_flags |= VM_INSERTPAGE;
        return insert_page(vma->vm_mm, addr, page, vma->vm_page_prot);
 }
 EXPORT_SYMBOL(vm_insert_page);
@@ -1319,7 +1325,7 @@ int remap_pfn_range(struct vm_area_struct *vma, unsigned long addr,
         * behaviour that some programs depend on. We mark the "original"
         * un-COW'ed pages by matching them up with "vma->vm_pgoff".
         */
-       if (!(vma->vm_flags & VM_SHARED)) {
+       if (is_cow_mapping(vma->vm_flags)) {
                if (addr != vma->vm_start || end != vma->vm_end)
                        return -EINVAL;
                vma->vm_pgoff = pfn;
@@ -1492,7 +1498,7 @@ gotten:
                update_mmu_cache(vma, address, entry);
                lazy_mmu_prot_update(entry);
                lru_cache_add_active(new_page);
-               page_add_anon_rmap(new_page, vma, address);
+               page_add_new_anon_rmap(new_page, vma, address);
 
                /* Free the old page.. */
                new_page = old_page;
@@ -1764,9 +1770,32 @@ out_big:
 out_busy:
        return -ETXTBSY;
 }
-
 EXPORT_SYMBOL(vmtruncate);
 
+int vmtruncate_range(struct inode *inode, loff_t offset, loff_t end)
+{
+       struct address_space *mapping = inode->i_mapping;
+
+       /*
+        * If the underlying filesystem is not going to provide
+        * a way to truncate a range of blocks (punch a hole) -
+        * we should return failure right now.
+        */
+       if (!inode->i_op || !inode->i_op->truncate_range)
+               return -ENOSYS;
+
+       mutex_lock(&inode->i_mutex);
+       down_write(&inode->i_alloc_sem);
+       unmap_mapping_range(mapping, offset, (end - offset), 1);
+       truncate_inode_pages_range(mapping, offset, end);
+       inode->i_op->truncate_range(inode, offset, end);
+       up_write(&inode->i_alloc_sem);
+       mutex_unlock(&inode->i_mutex);
+
+       return 0;
+}
+EXPORT_SYMBOL(vmtruncate_range);
+
 /* 
  * Primitive swap readahead code. We simply read an aligned block of
  * (1 << page_cluster) entries in the swap area. This method is chosen
@@ -1842,6 +1871,7 @@ static int do_swap_page(struct mm_struct *mm, struct vm_area_struct *vma,
                goto out;
 
        entry = pte_to_swp_entry(orig_pte);
+again:
        page = lookup_swap_cache(entry);
        if (!page) {
                swapin_readahead(entry, address, vma);
@@ -1865,6 +1895,12 @@ static int do_swap_page(struct mm_struct *mm, struct vm_area_struct *vma,
 
        mark_page_accessed(page);
        lock_page(page);
+       if (!PageSwapCache(page)) {
+               /* Page migration has occured */
+               unlock_page(page);
+               page_cache_release(page);
+               goto again;
+       }
 
        /*
         * Back out if somebody else already faulted in this pte.
@@ -1948,8 +1984,7 @@ static int do_anonymous_page(struct mm_struct *mm, struct vm_area_struct *vma,
                        goto release;
                inc_mm_counter(mm, anon_rss);
                lru_cache_add_active(page);
-               SetPageReferenced(page);
-               page_add_anon_rmap(page, vma, address);
+               page_add_new_anon_rmap(page, vma, address);
        } else {
                /* Map the ZERO_PAGE - vm_page_prot is readonly */
                page = ZERO_PAGE(address);
@@ -2080,7 +2115,7 @@ retry:
                if (anon) {
                        inc_mm_counter(mm, anon_rss);
                        lru_cache_add_active(new_page);
-                       page_add_anon_rmap(new_page, vma, address);
+                       page_add_new_anon_rmap(new_page, vma, address);
                } else {
                        inc_mm_counter(mm, file_rss);
                        page_add_file_rmap(new_page);
@@ -2239,6 +2274,8 @@ int __handle_mm_fault(struct mm_struct *mm, struct vm_area_struct *vma,
        return handle_pte_fault(mm, vma, address, pte, pmd, write_access);
 }
 
+EXPORT_SYMBOL_GPL(__handle_mm_fault);
+
 #ifndef __PAGETABLE_PUD_FOLDED
 /*
  * Allocate page upper directory.