X-Git-Url: http://ftp.safe.ca/?a=blobdiff_plain;f=mm%2Fmigrate.c;h=e9b161bde95b4c382092a1c94a8fcfbd4bcf58f0;hb=03c6d130f690dba46387480de80acf458a6fd14c;hp=033a12f4c9499657aa07b10860484757291cc0d0;hpb=742755a1d8ce2b548428f7aacf1758b4bba50080;p=safe%2Fjmp%2Flinux-2.6

diff --git a/mm/migrate.c b/mm/migrate.c
index 033a12f..e9b161b 100644
--- a/mm/migrate.c
+++ b/mm/migrate.c
@@ -27,6 +27,7 @@
 #include <linux/writeback.h>
 #include <linux/mempolicy.h>
 #include <linux/vmalloc.h>
+#include <linux/security.h>
 
 #include "internal.h"
 
@@ -293,7 +294,7 @@ out:
 static int migrate_page_move_mapping(struct address_space *mapping,
 		struct page *newpage, struct page *page)
 {
-	struct page **radix_pointer;
+	void **pslot;
 
 	if (!mapping) {
 		/* Anonymous page */
@@ -304,12 +305,11 @@ static int migrate_page_move_mapping(struct address_space *mapping,
 
 	write_lock_irq(&mapping->tree_lock);
 
-	radix_pointer = (struct page **)radix_tree_lookup_slot(
-						&mapping->page_tree,
-						page_index(page));
+	pslot = radix_tree_lookup_slot(&mapping->page_tree,
+ 					page_index(page));
 
 	if (page_count(page) != 2 + !!PagePrivate(page) ||
-			*radix_pointer != page) {
+			(struct page *)radix_tree_deref_slot(pslot) != page) {
 		write_unlock_irq(&mapping->tree_lock);
 		return -EAGAIN;
 	}
@@ -317,7 +317,7 @@ static int migrate_page_move_mapping(struct address_space *mapping,
 	/*
 	 * Now we know that no one else is looking at the page.
 	 */
-	get_page(newpage);
+	get_page(newpage);	/* add cache reference */
 #ifdef CONFIG_SWAP
 	if (PageSwapCache(page)) {
 		SetPageSwapCache(newpage);
@@ -325,8 +325,14 @@ static int migrate_page_move_mapping(struct address_space *mapping,
 	}
 #endif
 
-	*radix_pointer = newpage;
+	radix_tree_replace_slot(pslot, newpage);
+
+	/*
+	 * Drop cache reference from old page.
+	 * We know this isn't the last reference.
+	 */
 	__put_page(page);
+
 	write_unlock_irq(&mapping->tree_lock);
 
 	return 0;
@@ -408,6 +414,7 @@ int migrate_page(struct address_space *mapping,
 }
 EXPORT_SYMBOL(migrate_page);
 
+#ifdef CONFIG_BLOCK
 /*
  * Migration function for pages with buffers. This function can only be used
  * if the underlying filesystem guarantees that no other references to "page"
@@ -465,6 +472,7 @@ int buffer_migrate_page(struct address_space *mapping,
 	return 0;
 }
 EXPORT_SYMBOL(buffer_migrate_page);
+#endif
 
 /*
  * Writeback a page to clean the dirty state
@@ -524,7 +532,7 @@ static int fallback_migrate_page(struct address_space *mapping,
 	 * Buffers may be managed in a filesystem specific way.
 	 * We must have no buffers or drop them.
 	 */
-	if (page_has_buffers(page) &&
+	if (PagePrivate(page) &&
 	    !try_to_release_page(page, GFP_KERNEL))
 		return -EAGAIN;
 
@@ -615,15 +623,13 @@ static int unmap_and_move(new_page_t get_new_page, unsigned long private,
 	/*
 	 * Establish migration ptes or remove ptes
 	 */
-	if (try_to_unmap(page, 1) != SWAP_FAIL) {
-		if (!page_mapped(page))
-			rc = move_to_new_page(newpage, page);
-	} else
-		/* A vma has VM_LOCKED set -> permanent failure */
-		rc = -EPERM;
+	try_to_unmap(page, 1);
+	if (!page_mapped(page))
+		rc = move_to_new_page(newpage, page);
 
 	if (rc)
 		remove_migration_ptes(page, page);
+
 unlock:
 	unlock_page(page);
 
@@ -742,7 +748,7 @@ static struct page *new_page_node(struct page *p, unsigned long private,
 
 	*result = &pm->status;
 
-	return alloc_pages_node(pm->node, GFP_HIGHUSER, 0);
+	return alloc_pages_node(pm->node, GFP_HIGHUSER | GFP_THISNODE, 0);
 }
 
 /*
@@ -905,6 +911,11 @@ asmlinkage long sys_move_pages(pid_t pid, unsigned long nr_pages,
 		goto out2;
 	}
 
+ 	err = security_task_movememory(task);
+ 	if (err)
+ 		goto out2;
+
+
 	task_nodes = cpuset_mems_allowed(task);
 
 	/* Limit nr_pages so that the multiplication may not overflow */
@@ -946,7 +957,8 @@ asmlinkage long sys_move_pages(pid_t pid, unsigned long nr_pages,
 				goto out;
 
 			pm[i].node = node;
-		}
+		} else
+			pm[i].node = 0;	/* anything to not match MAX_NUMNODES */
 	}
 	/* End marker */
 	pm[nr_pages].node = MAX_NUMNODES;
@@ -970,3 +982,23 @@ out2:
 }
 #endif
 
+/*
+ * Call migration functions in the vma_ops that may prepare
+ * memory in a vm for migration. migration functions may perform
+ * the migration for vmas that do not have an underlying page struct.
+ */
+int migrate_vmas(struct mm_struct *mm, const nodemask_t *to,
+	const nodemask_t *from, unsigned long flags)
+{
+ 	struct vm_area_struct *vma;
+ 	int err = 0;
+
+ 	for(vma = mm->mmap; vma->vm_next && !err; vma = vma->vm_next) {
+ 		if (vma->vm_ops && vma->vm_ops->migrate) {
+ 			err = vma->vm_ops->migrate(vma, to, from, flags);
+ 			if (err)
+ 				break;
+ 		}
+ 	}
+ 	return err;
+}