release/src-rt-6.x.4708/linux/linux-2.6.36/fs/exofs/file.c

   1 /*
   2  * Copyright (C) 2005, 2006
   3  * Avishay Traeger (avishay@gmail.com)
   4  * Copyright (C) 2008, 2009
   5  * Boaz Harrosh <bharrosh@panasas.com>
   6  *
   7  * Copyrights for code taken from ext2:
   8  *     Copyright (C) 1992, 1993, 1994, 1995
   9  *     Remy Card (card@masi.ibp.fr)
  10  *     Laboratoire MASI - Institut Blaise Pascal
  11  *     Universite Pierre et Marie Curie (Paris VI)
  12  *     from
  13  *     linux/fs/minix/inode.c
  14  *     Copyright (C) 1991, 1992  Linus Torvalds
  15  *
  16  * This file is part of exofs.
  17  *
  18  * exofs is free software; you can redistribute it and/or modify
  19  * it under the terms of the GNU General Public License as published by
  20  * the Free Software Foundation.  Since it is based on ext2, and the only
  21  * valid version of GPL for the Linux kernel is version 2, the only valid
  22  * version of GPL for exofs is version 2.
  23  *
  24  * exofs is distributed in the hope that it will be useful,
  25  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  26  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  27  * GNU General Public License for more details.
  28  *
  29  * You should have received a copy of the GNU General Public License
  30  * along with exofs; if not, write to the Free Software
  31  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  32  */
  33 #include "exofs.h"
  34
  35 static int exofs_release_file(struct inode *inode, struct file *filp)
  36 {
  37         return 0;
  38 }
  39
  40 /* exofs_file_fsync - flush the inode to disk
  41  *
  42  *   Note, in exofs all metadata is written as part of inode, regardless.
  43  *   The writeout is synchronous
  44  */
  45 static int exofs_file_fsync(struct file *filp, int datasync)
  46 {
  47         int ret;
  48         struct inode *inode = filp->f_mapping->host;
  49         struct writeback_control wbc = {
  50                 .sync_mode = WB_SYNC_ALL,
  51                 .nr_to_write = 0, /* metadata-only; caller takes care of data */
  52         };
  53         struct super_block *sb;
  54
  55         if (!(inode->i_state & I_DIRTY))
  56                 return 0;
  57         if (datasync && !(inode->i_state & I_DIRTY_DATASYNC))
  58                 return 0;
  59
  60         ret = sync_inode(inode, &wbc);
  61
  62         /* This is a good place to write the sb */
  63         /* TODO: Sechedule an sb-sync on create */
  64         sb = inode->i_sb;
  65         if (sb->s_dirt)
  66                 exofs_sync_fs(sb, 1);
  67
  68         return ret;
  69 }
  70
  71 static int exofs_flush(struct file *file, fl_owner_t id)
  72 {
  73         int ret = vfs_fsync(file, 0);
  74         /* TODO: Flush the OSD target */
  75         return ret;
  76 }
  77
  78 const struct file_operations exofs_file_operations = {
  79         .llseek         = generic_file_llseek,
  80         .read           = do_sync_read,
  81         .write          = do_sync_write,
  82         .aio_read       = generic_file_aio_read,
  83         .aio_write      = generic_file_aio_write,
  84         .mmap           = generic_file_mmap,
  85         .open           = generic_file_open,
  86         .release        = exofs_release_file,
  87         .fsync          = exofs_file_fsync,
  88         .flush          = exofs_flush,
  89         .splice_read    = generic_file_splice_read,
  90         .splice_write   = generic_file_splice_write,
  91 };
  92
  93 const struct inode_operations exofs_file_inode_operations = {
  94         .setattr        = exofs_setattr,
  95 };