/*
 *   Copyright (C) International Business Machines Corp., 2000-2002
 *   Portions Copyright (C) Christoph Hellwig, 2001-2002
 *
 *   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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 */

#include <linux/mm.h>
#include <linux/fs.h>
#include <linux/quotaops.h>
#include "jfs_incore.h"
#include "jfs_inode.h"
#include "jfs_dmap.h"
#include "jfs_txnmgr.h"
#include "jfs_xattr.h"
#include "jfs_acl.h"
#include "jfs_debug.h"

int jfs_fsync(struct file *file, loff_t start, loff_t end, int datasync)
{
        struct inode *inode = file->f_mapping->host;
        int rc = 0;

        rc = filemap_write_and_wait_range(inode->i_mapping, start, end);
        if (rc)
                return rc;

        mutex_lock(&inode->i_mutex);
        if (!(inode->i_state & I_DIRTY) ||
            (datasync && !(inode->i_state & I_DIRTY_DATASYNC))) {
                /* Make sure committed changes hit the disk */
                jfs_flush_journal(JFS_SBI(inode->i_sb)->log, 1);
                mutex_unlock(&inode->i_mutex);
                return rc;
        }

        rc |= jfs_commit_inode(inode, 1);
        mutex_unlock(&inode->i_mutex);

        return rc ? -EIO : 0;
}

static int jfs_open(struct inode *inode, struct file *file)
{
        int rc;

        if ((rc = dquot_file_open(inode, file)))
                return rc;

        /*
         * We attempt to allow only one "active" file open per aggregate
         * group.  Otherwise, appending to files in parallel can cause
         * fragmentation within the files.
         *
         * If the file is empty, it was probably just created and going
         * to be written to.  If it has a size, we'll hold off until the
         * file is actually grown.
         */
        if (S_ISREG(inode->i_mode) && file->f_mode & FMODE_WRITE &&
            (inode->i_size == 0)) {
                struct jfs_inode_info *ji = JFS_IP(inode);
                spin_lock_irq(&ji->ag_lock);
                if (ji->active_ag == -1) {
                        struct jfs_sb_info *jfs_sb = JFS_SBI(inode->i_sb);
                        ji->active_ag = BLKTOAG(addressPXD(&ji->ixpxd), jfs_sb);
                        atomic_inc( &jfs_sb->bmap->db_active[ji->active_ag]);
                }
                spin_unlock_irq(&ji->ag_lock);
        }

        return 0;
}
static int jfs_release(struct inode *inode, struct file *file)
{
        struct jfs_inode_info *ji = JFS_IP(inode);

        spin_lock_irq(&ji->ag_lock);
        if (ji->active_ag != -1) {
                struct bmap *bmap = JFS_SBI(inode->i_sb)->bmap;
                atomic_dec(&bmap->db_active[ji->active_ag]);
                ji->active_ag = -1;
        }
        spin_unlock_irq(&ji->ag_lock);

        return 0;
}

int jfs_setattr(struct dentry *dentry, struct iattr *iattr)
{
        struct inode *inode = dentry->d_inode;
        int rc;

        rc = inode_change_ok(inode, iattr);
        if (rc)
                return rc;

        if (is_quota_modification(inode, iattr))
                dquot_initialize(inode);
        if ((iattr->ia_valid & ATTR_UID && !uid_eq(iattr->ia_uid, inode->i_uid)) ||
            (iattr->ia_valid & ATTR_GID && !gid_eq(iattr->ia_gid, inode->i_gid))) {
                rc = dquot_transfer(inode, iattr);
                if (rc)
                        return rc;
        }

        if ((iattr->ia_valid & ATTR_SIZE) &&
            iattr->ia_size != i_size_read(inode)) {
                inode_dio_wait(inode);

                rc = inode_newsize_ok(inode, iattr->ia_size);
                if (rc)
                        return rc;

                truncate_setsize(inode, iattr->ia_size);
                jfs_truncate(inode);
        }

        setattr_copy(inode, iattr);
        mark_inode_dirty(inode);

        if (iattr->ia_valid & ATTR_MODE)
                rc = jfs_acl_chmod(inode);
        return rc;
}

const struct inode_operations jfs_file_inode_operations = {
        .setxattr       = jfs_setxattr,
        .getxattr       = jfs_getxattr,
        .listxattr      = jfs_listxattr,
        .removexattr    = jfs_removexattr,
        .setattr        = jfs_setattr,
#ifdef CONFIG_JFS_POSIX_ACL
        .get_acl        = jfs_get_acl,
#endif
};

const struct file_operations jfs_file_operations = {
        .open           = jfs_open,
        .llseek         = generic_file_llseek,
        .write          = do_sync_write,
        .read           = do_sync_read,
        .aio_read       = generic_file_aio_read,
        .aio_write      = generic_file_aio_write,
        .mmap           = generic_file_mmap,
        .splice_read    = generic_file_splice_read,
        .splice_write   = generic_file_splice_write,
        .fsync          = jfs_fsync,
        .release        = jfs_release,
        .unlocked_ioctl = jfs_ioctl,
#ifdef CONFIG_COMPAT
        .compat_ioctl   = jfs_compat_ioctl,
#endif
};