1 files changed, 48 insertions, 14 deletions

diff --git a/fs/buffer.c b/fs/buffer.c
index b71e52925c8..c2fa1be4923 100644
--- a/fs/buffer.c
+++ b/fs/buffer.c
@@ -199,13 +199,13 @@ __find_get_block_slow(struct block_device *bdev, sector_t block)
 	head = page_buffers(page);
 	bh = head;
 	do {
-		if (bh->b_blocknr == block) {
+		if (!buffer_mapped(bh))
+			all_mapped = 0;
+		else if (bh->b_blocknr == block) {
 			ret = bh;
 			get_bh(bh);
 			goto out_unlock;
 		}
-		if (!buffer_mapped(bh))
-			all_mapped = 0;
 		bh = bh->b_this_page;
 	} while (bh != head);
 
@@ -290,7 +290,7 @@ static void free_more_memory(void)
 						&zone);
 		if (zone)
 			try_to_free_pages(node_zonelist(nid, GFP_NOFS), 0,
-						GFP_NOFS);
+						GFP_NOFS, NULL);
 	}
 }
 
@@ -547,6 +547,39 @@ repeat:
 	return err;
 }
 
+void do_thaw_all(unsigned long unused)
+{
+	struct super_block *sb;
+	char b[BDEVNAME_SIZE];
+
+	spin_lock(&sb_lock);
+restart:
+	list_for_each_entry(sb, &super_blocks, s_list) {
+		sb->s_count++;
+		spin_unlock(&sb_lock);
+		down_read(&sb->s_umount);
+		while (sb->s_bdev && !thaw_bdev(sb->s_bdev, sb))
+			printk(KERN_WARNING "Emergency Thaw on %s\n",
+			       bdevname(sb->s_bdev, b));
+		up_read(&sb->s_umount);
+		spin_lock(&sb_lock);
+		if (__put_super_and_need_restart(sb))
+			goto restart;
+	}
+	spin_unlock(&sb_lock);
+	printk(KERN_WARNING "Emergency Thaw complete\n");
+}
+
+/**
+ * emergency_thaw_all -- forcibly thaw every frozen filesystem
+ *
+ * Used for emergency unfreeze of all filesystems via SysRq
+ */
+void emergency_thaw_all(void)
+{
+	pdflush_operation(do_thaw_all, 0);
+}
+
 /**
  * sync_mapping_buffers - write out & wait upon a mapping's "associated" buffers
  * @mapping: the mapping which wants those buffers written
@@ -621,14 +654,7 @@ static void __set_page_dirty(struct page *page,
 	spin_lock_irq(&mapping->tree_lock);
 	if (page->mapping) {	/* Race with truncate? */
 		WARN_ON_ONCE(warn && !PageUptodate(page));
-
-		if (mapping_cap_account_dirty(mapping)) {
-			__inc_zone_page_state(page, NR_FILE_DIRTY);
-			__inc_bdi_stat(mapping->backing_dev_info,
-					BDI_RECLAIMABLE);
-			task_dirty_inc(current);
-			task_io_account_write(PAGE_CACHE_SIZE);
-		}
+		account_page_dirtied(page, mapping);
 		radix_tree_tag_set(&mapping->page_tree,
 				page_index(page), PAGECACHE_TAG_DIRTY);
 	}
@@ -2320,13 +2346,14 @@ int block_commit_write(struct page *page, unsigned from, unsigned to)
  * unlock the page.
  */
 int
-block_page_mkwrite(struct vm_area_struct *vma, struct page *page,
+block_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf,
 		   get_block_t get_block)
 {
+	struct page *page = vmf->page;
 	struct inode *inode = vma->vm_file->f_path.dentry->d_inode;
 	unsigned long end;
 	loff_t size;
-	int ret = -EINVAL;
+	int ret = VM_FAULT_NOPAGE; /* make the VM retry the fault */
 
 	lock_page(page);
 	size = i_size_read(inode);
@@ -2346,6 +2373,13 @@ block_page_mkwrite(struct vm_area_struct *vma, struct page *page,
 	if (!ret)
 		ret = block_commit_write(page, 0, end);
 
+	if (unlikely(ret)) {
+		if (ret == -ENOMEM)
+			ret = VM_FAULT_OOM;
+		else /* -ENOSPC, -EIO, etc */
+			ret = VM_FAULT_SIGBUS;
+	}
+
 out_unlock:
 	unlock_page(page);
 	return ret;