1 files changed, 69 insertions, 7 deletions

diff --git a/fs/ext2/file.c b/fs/ext2/file.c
index 5efeefe17abb..423cc01c9d41 100644
--- a/fs/ext2/file.c
+++ b/fs/ext2/file.c
@@ -22,11 +22,59 @@
 #include <linux/pagemap.h>
 #include <linux/dax.h>
 #include <linux/quotaops.h>
+#include <linux/iomap.h>
+#include <linux/uio.h>
 #include "ext2.h"
 #include "xattr.h"
 #include "acl.h"
 
 #ifdef CONFIG_FS_DAX
+static ssize_t ext2_dax_read_iter(struct kiocb *iocb, struct iov_iter *to)
+{
+        struct inode *inode = iocb->ki_filp->f_mapping->host;
+        ssize_t ret;
+
+        if (!iov_iter_count(to))
+                return 0; /* skip atime */
+
+        inode_lock_shared(inode);
+        ret = iomap_dax_rw(iocb, to, &ext2_iomap_ops);
+        inode_unlock_shared(inode);
+
+        file_accessed(iocb->ki_filp);
+        return ret;
+}
+
+static ssize_t ext2_dax_write_iter(struct kiocb *iocb, struct iov_iter *from)
+{
+        struct file *file = iocb->ki_filp;
+        struct inode *inode = file->f_mapping->host;
+        ssize_t ret;
+
+        inode_lock(inode);
+        ret = generic_write_checks(iocb, from);
+        if (ret <= 0)
+                goto out_unlock;
+        ret = file_remove_privs(file);
+        if (ret)
+                goto out_unlock;
+        ret = file_update_time(file);
+        if (ret)
+                goto out_unlock;
+
+        ret = iomap_dax_rw(iocb, from, &ext2_iomap_ops);
+        if (ret > 0 && iocb->ki_pos > i_size_read(inode)) {
+                i_size_write(inode, iocb->ki_pos);
+                mark_inode_dirty(inode);
+        }
+
+out_unlock:
+        inode_unlock(inode);
+        if (ret > 0)
+                ret = generic_write_sync(iocb, ret);
+        return ret;
+}
+
 /*
  * The lock ordering for ext2 DAX fault paths is:
  *
@@ -51,7 +99,7 @@ static int ext2_dax_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
         }
         down_read(&ei->dax_sem);
 
-        ret = dax_fault(vma, vmf, ext2_get_block);
+        ret = iomap_dax_fault(vma, vmf, &ext2_iomap_ops);
 
         up_read(&ei->dax_sem);
         if (vmf->flags & FAULT_FLAG_WRITE)
@@ -156,14 +204,28 @@ int ext2_fsync(struct file *file, loff_t start, loff_t end, int datasync)
         return ret;
 }
 
-/*
- * We have mostly NULL's here: the current defaults are ok for
- * the ext2 filesystem.
- */
+static ssize_t ext2_file_read_iter(struct kiocb *iocb, struct iov_iter *to)
+{
+#ifdef CONFIG_FS_DAX
+        if (IS_DAX(iocb->ki_filp->f_mapping->host))
+                return ext2_dax_read_iter(iocb, to);
+#endif
+        return generic_file_read_iter(iocb, to);
+}
+
+static ssize_t ext2_file_write_iter(struct kiocb *iocb, struct iov_iter *from)
+{
+#ifdef CONFIG_FS_DAX
+        if (IS_DAX(iocb->ki_filp->f_mapping->host))
+                return ext2_dax_write_iter(iocb, from);
+#endif
+        return generic_file_write_iter(iocb, from);
+}
+
 const struct file_operations ext2_file_operations = {
         .llseek         = generic_file_llseek,
-        .read_iter      = generic_file_read_iter,
-        .write_iter     = generic_file_write_iter,
+        .read_iter      = ext2_file_read_iter,
+        .write_iter     = ext2_file_write_iter,
         .unlocked_ioctl = ext2_ioctl,
 #ifdef CONFIG_COMPAT
         .compat_ioctl   = ext2_compat_ioctl,