1 files changed, 29 insertions, 2 deletions

diff --git a/mm/filemap.c b/mm/filemap.c
index a4a5260b0279..fa5ca304148e 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -1712,8 +1712,35 @@ page_not_uptodate:
 }
 EXPORT_SYMBOL(filemap_fault);
 
+int filemap_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf)
+{
+        struct page *page = vmf->page;
+        struct inode *inode = vma->vm_file->f_path.dentry->d_inode;
+        int ret = VM_FAULT_LOCKED;
+
+        sb_start_pagefault(inode->i_sb);
+        file_update_time(vma->vm_file);
+        lock_page(page);
+        if (page->mapping != inode->i_mapping) {
+                unlock_page(page);
+                ret = VM_FAULT_NOPAGE;
+                goto out;
+        }
+        /*
+         * We mark the page dirty already here so that when freeze is in
+         * progress, we are guaranteed that writeback during freezing will
+         * see the dirty page and writeprotect it again.
+         */
+        set_page_dirty(page);
+out:
+        sb_end_pagefault(inode->i_sb);
+        return ret;
+}
+EXPORT_SYMBOL(filemap_page_mkwrite);
+
 const struct vm_operations_struct generic_file_vm_ops = {
         .fault          = filemap_fault,
+        .page_mkwrite   = filemap_page_mkwrite,
 };
 
 /* This is used for a general mmap of a disk file */
@@ -2407,8 +2434,6 @@ ssize_t __generic_file_aio_write(struct kiocb *iocb, const struct iovec *iov,
         count = ocount;
         pos = *ppos;
 
-        vfs_check_frozen(inode->i_sb, SB_FREEZE_WRITE);
-
         /* We can write back this queue in page reclaim */
         current->backing_dev_info = mapping->backing_dev_info;
         written = 0;
@@ -2507,6 +2532,7 @@ ssize_t generic_file_aio_write(struct kiocb *iocb, const struct iovec *iov,
 
         BUG_ON(iocb->ki_pos != pos);
 
+        sb_start_write(inode->i_sb);
         mutex_lock(&inode->i_mutex);
         blk_start_plug(&plug);
         ret = __generic_file_aio_write(iocb, iov, nr_segs, &iocb->ki_pos);
@@ -2520,6 +2546,7 @@ ssize_t generic_file_aio_write(struct kiocb *iocb, const struct iovec *iov,
                         ret = err;
         }
         blk_finish_plug(&plug);
+        sb_end_write(inode->i_sb);
         return ret;
 }
 EXPORT_SYMBOL(generic_file_aio_write);