nilfs2: file operations

This adds primitives for regular file handling.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/fs/nilfs2/file.c b/fs/nilfs2/file.c
new file mode 100644 (file)
index 0000000..7ddd42e
--- /dev/null
+++ b/fs/nilfs2/file.c
@@ -0,0 +1,125 @@
+/*
+ * file.c - NILFS regular file handling primitives including fsync().
+ *
+ * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ *
+ * Written by Amagai Yoshiji <amagai@osrg.net>,
+ *            Ryusuke Konishi <ryusuke@osrg.net>
+ */
+
+#include <linux/fs.h>
+#include <linux/mm.h>
+#include <linux/writeback.h>
+#include "nilfs.h"
+#include "segment.h"
+
+int nilfs_sync_file(struct file *file, struct dentry *dentry, int datasync)
+{
+       /*
+        * Called from fsync() system call
+        * This is the only entry point that can catch write and synch
+        * timing for both data blocks and intermediate blocks.
+        *
+        * This function should be implemented when the writeback function
+        * will be implemented.
+        */
+       struct inode *inode = dentry->d_inode;
+       int err;
+
+       if (!nilfs_inode_dirty(inode))
+               return 0;
+
+       if (datasync)
+               err = nilfs_construct_dsync_segment(inode->i_sb, inode);
+       else
+               err = nilfs_construct_segment(inode->i_sb);
+
+       return err;
+}
+
+static ssize_t
+nilfs_file_aio_write(struct kiocb *iocb, const struct iovec *iov,
+                    unsigned long nr_segs, loff_t pos)
+{
+       struct file *file = iocb->ki_filp;
+       struct inode *inode = file->f_dentry->d_inode;
+       ssize_t ret;
+
+       ret = generic_file_aio_write(iocb, iov, nr_segs, pos);
+       if (ret <= 0)
+               return ret;
+
+       if ((file->f_flags & O_SYNC) || IS_SYNC(inode)) {
+               int err;
+
+               err = nilfs_construct_dsync_segment(inode->i_sb, inode);
+               if (unlikely(err))
+                       return err;
+       }
+       return ret;
+}
+
+static int nilfs_page_mkwrite(struct vm_area_struct *vma, struct page *page)
+{
+       if (!(vma->vm_flags & (VM_WRITE | VM_MAYWRITE)))
+               return -EPERM;
+       SetPageChecked(page);
+       wait_on_page_writeback(page);
+       return 0;
+}
+
+struct vm_operations_struct nilfs_file_vm_ops = {
+       .fault          = filemap_fault,
+       .page_mkwrite   = nilfs_page_mkwrite,
+};
+
+static int nilfs_file_mmap(struct file *file, struct vm_area_struct *vma)
+{
+       file_accessed(file);
+       vma->vm_ops = &nilfs_file_vm_ops;
+       vma->vm_flags |= VM_CAN_NONLINEAR;
+       return 0;
+}
+
+/*
+ * We have mostly NULL's here: the current defaults are ok for
+ * the nilfs filesystem.
+ */
+struct file_operations nilfs_file_operations = {
+       .llseek         = generic_file_llseek,
+       .read           = do_sync_read,
+       .write          = do_sync_write,
+       .aio_read       = generic_file_aio_read,
+       .aio_write      = nilfs_file_aio_write,
+       .ioctl          = nilfs_ioctl,
+#ifdef CONFIG_COMPAT
+       .compat_ioctl   = nilfs_compat_ioctl,
+#endif /* CONFIG_COMPAT */
+       .mmap           = nilfs_file_mmap,
+       .open           = generic_file_open,
+       /* .release     = nilfs_release_file, */
+       .fsync          = nilfs_sync_file,
+       .splice_read    = generic_file_splice_read,
+};
+
+struct inode_operations nilfs_file_inode_operations = {
+       .truncate       = nilfs_truncate,
+       .setattr        = nilfs_setattr,
+       .permission     = nilfs_permission,
+};
+
+/* end of file */