Add the rt linux 4.1.3-rt3 as base

[kvmfornfv.git] / kernel / fs / nilfs2 / file.c

diff --git a/kernel/fs/nilfs2/file.c b/kernel/fs/nilfs2/file.c
new file mode 100644 (file)
index 0000000..54575e3
--- /dev/null
+++ b/kernel/fs/nilfs2/file.c
@@ -0,0 +1,165 @@
+/*
+ * 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, loff_t start, loff_t end, 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 the_nilfs *nilfs;
+       struct inode *inode = file->f_mapping->host;
+       int err = 0;
+
+       if (nilfs_inode_dirty(inode)) {
+               if (datasync)
+                       err = nilfs_construct_dsync_segment(inode->i_sb, inode,
+                                                           start, end);
+               else
+                       err = nilfs_construct_segment(inode->i_sb);
+       }
+
+       nilfs = inode->i_sb->s_fs_info;
+       if (!err)
+               err = nilfs_flush_device(nilfs);
+
+       return err;
+}
+
+static int nilfs_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf)
+{
+       struct page *page = vmf->page;
+       struct inode *inode = file_inode(vma->vm_file);
+       struct nilfs_transaction_info ti;
+       int ret = 0;
+
+       if (unlikely(nilfs_near_disk_full(inode->i_sb->s_fs_info)))
+               return VM_FAULT_SIGBUS; /* -ENOSPC */
+
+       sb_start_pagefault(inode->i_sb);
+       lock_page(page);
+       if (page->mapping != inode->i_mapping ||
+           page_offset(page) >= i_size_read(inode) || !PageUptodate(page)) {
+               unlock_page(page);
+               ret = -EFAULT;  /* make the VM retry the fault */
+               goto out;
+       }
+
+       /*
+        * check to see if the page is mapped already (no holes)
+        */
+       if (PageMappedToDisk(page))
+               goto mapped;
+
+       if (page_has_buffers(page)) {
+               struct buffer_head *bh, *head;
+               int fully_mapped = 1;
+
+               bh = head = page_buffers(page);
+               do {
+                       if (!buffer_mapped(bh)) {
+                               fully_mapped = 0;
+                               break;
+                       }
+               } while (bh = bh->b_this_page, bh != head);
+
+               if (fully_mapped) {
+                       SetPageMappedToDisk(page);
+                       goto mapped;
+               }
+       }
+       unlock_page(page);
+
+       /*
+        * fill hole blocks
+        */
+       ret = nilfs_transaction_begin(inode->i_sb, &ti, 1);
+       /* never returns -ENOMEM, but may return -ENOSPC */
+       if (unlikely(ret))
+               goto out;
+
+       file_update_time(vma->vm_file);
+       ret = __block_page_mkwrite(vma, vmf, nilfs_get_block);
+       if (ret) {
+               nilfs_transaction_abort(inode->i_sb);
+               goto out;
+       }
+       nilfs_set_file_dirty(inode, 1 << (PAGE_SHIFT - inode->i_blkbits));
+       nilfs_transaction_commit(inode->i_sb);
+
+ mapped:
+       wait_for_stable_page(page);
+ out:
+       sb_end_pagefault(inode->i_sb);
+       return block_page_mkwrite_return(ret);
+}
+
+static const struct vm_operations_struct nilfs_file_vm_ops = {
+       .fault          = filemap_fault,
+       .map_pages      = filemap_map_pages,
+       .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;
+       return 0;
+}
+
+/*
+ * We have mostly NULL's here: the current defaults are ok for
+ * the nilfs filesystem.
+ */
+const struct file_operations nilfs_file_operations = {
+       .llseek         = generic_file_llseek,
+       .read_iter      = generic_file_read_iter,
+       .write_iter     = generic_file_write_iter,
+       .unlocked_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,
+};
+
+const struct inode_operations nilfs_file_inode_operations = {
+       .setattr        = nilfs_setattr,
+       .permission     = nilfs_permission,
+       .fiemap         = nilfs_fiemap,
+};
+
+/* end of file */