LXR linux/fs/jfs/file.c

   1/*
   2 *   Copyright (C) International Business Machines Corp., 2000-2002
   3 *   Portions Copyright (C) Christoph Hellwig, 2001-2002
   4 *
   5 *   This program is free software;  you can redistribute it and/or modify
   6 *   it under the terms of the GNU General Public License as published by
   7 *   the Free Software Foundation; either version 2 of the License, or
   8 *   (at your option) any later version.
   9 *
  10 *   This program is distributed in the hope that it will be useful,
  11 *   but WITHOUT ANY WARRANTY;  without even the implied warranty of
  12 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See
  13 *   the GNU General Public License for more details.
  14 *
  15 *   You should have received a copy of the GNU General Public License
  16 *   along with this program;  if not, write to the Free Software
  17 *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  18 */
  19
  20#include <linux/fs.h>
  21#include "jfs_incore.h"
  22#include "jfs_inode.h"
  23#include "jfs_dmap.h"
  24#include "jfs_txnmgr.h"
  25#include "jfs_xattr.h"
  26#include "jfs_acl.h"
  27#include "jfs_debug.h"
  28
  29int jfs_fsync(struct file *file, struct dentry *dentry, int datasync)
  30{
  31        struct inode *inode = dentry->d_inode;
  32        int rc = 0;
  33
  34        if (!(inode->i_state & I_DIRTY) ||
  35            (datasync && !(inode->i_state & I_DIRTY_DATASYNC))) {
  36                /* Make sure committed changes hit the disk */
  37                jfs_flush_journal(JFS_SBI(inode->i_sb)->log, 1);
  38                return rc;
  39        }
  40
  41        rc |= jfs_commit_inode(inode, 1);
  42
  43        return rc ? -EIO : 0;
  44}
  45
  46static int jfs_open(struct inode *inode, struct file *file)
  47{
  48        int rc;
  49
  50        if ((rc = generic_file_open(inode, file)))
  51                return rc;
  52
  53        /*
  54         * We attempt to allow only one "active" file open per aggregate
  55         * group.  Otherwise, appending to files in parallel can cause
  56         * fragmentation within the files.
  57         *
  58         * If the file is empty, it was probably just created and going
  59         * to be written to.  If it has a size, we'll hold off until the
  60         * file is actually grown.
  61         */
  62        if (S_ISREG(inode->i_mode) && file->f_mode & FMODE_WRITE &&
  63            (inode->i_size == 0)) {
  64                struct jfs_inode_info *ji = JFS_IP(inode);
  65                spin_lock_irq(&ji->ag_lock);
  66                if (ji->active_ag == -1) {
  67                        ji->active_ag = ji->agno;
  68                        atomic_inc(
  69                            &JFS_SBI(inode->i_sb)->bmap->db_active[ji->agno]);
  70                }
  71                spin_unlock_irq(&ji->ag_lock);
  72        }
  73
  74        return 0;
  75}
  76static int jfs_release(struct inode *inode, struct file *file)
  77{
  78        struct jfs_inode_info *ji = JFS_IP(inode);
  79
  80        spin_lock_irq(&ji->ag_lock);
  81        if (ji->active_ag != -1) {
  82                struct bmap *bmap = JFS_SBI(inode->i_sb)->bmap;
  83                atomic_dec(&bmap->db_active[ji->active_ag]);
  84                ji->active_ag = -1;
  85        }
  86        spin_unlock_irq(&ji->ag_lock);
  87
  88        return 0;
  89}
  90
  91const struct inode_operations jfs_file_inode_operations = {
  92        .truncate       = jfs_truncate,
  93        .setxattr       = jfs_setxattr,
  94        .getxattr       = jfs_getxattr,
  95        .listxattr      = jfs_listxattr,
  96        .removexattr    = jfs_removexattr,
  97#ifdef CONFIG_JFS_POSIX_ACL
  98        .setattr        = jfs_setattr,
  99        .check_acl      = jfs_check_acl,
 100#endif
 101};
 102
 103const struct file_operations jfs_file_operations = {
 104        .open           = jfs_open,
 105        .llseek         = generic_file_llseek,
 106        .write          = do_sync_write,
 107        .read           = do_sync_read,
 108        .aio_read       = generic_file_aio_read,
 109        .aio_write      = generic_file_aio_write,
 110        .mmap           = generic_file_mmap,
 111        .splice_read    = generic_file_splice_read,
 112        .splice_write   = generic_file_splice_write,
 113        .fsync          = jfs_fsync,
 114        .release        = jfs_release,
 115        .unlocked_ioctl = jfs_ioctl,
 116#ifdef CONFIG_COMPAT
 117        .compat_ioctl   = jfs_compat_ioctl,
 118#endif
 119};
 120