fs/smbsrv/smb_flush.c

/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */
/*
 * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 *
 * Copyright 2016 Syneto S.R.L. All rights reserved.
 */

/*
 * The flush SMB is sent to ensure all data and allocation information
 * for the corresponding file has been written to stable storage. This
 * is a synchronous request. The response should not be sent until the
 * writes are complete.
 *
 * The SmbFlush request is described in CIFS/1.0 1996 Section 3.9.14.
 *
 * CIFS/1.0 June 13, 1996
 * Heizer, et al
 * draft-heizer-cifs-v1-spec-00.txt
 */

#include <smbsrv/smb_kproto.h>
#include <smbsrv/smb_fsops.h>


/*
 * smb_com_flush
 *
 * Flush any cached data for a specified file, or for all files that
 * this client has open, to stable storage. If the fid is valid (i.e.
 * not 0xFFFF), we flush only that file. Otherwise we flush all files
 * associated with this client.
 *
 * We need to protect the list because there's a good chance we'll
 * block during the flush operation.
 */
smb_sdrc_t
smb_pre_flush(smb_request_t *sr)
{
    int rc;

    rc = smbsr_decode_vwv(sr, "w", &sr->smb_fid);

    DTRACE_SMB_1(op__Flush__start, smb_request_t *, sr);

    return ((rc == 0) ? SDRC_SUCCESS : SDRC_ERROR);
}

void
smb_post_flush(smb_request_t *sr)
{
    DTRACE_SMB_1(op__Flush__done, smb_request_t *, sr);
}

smb_sdrc_t
smb_com_flush(smb_request_t *sr)
{
    smb_ofile_t *file;
    smb_llist_t *flist;
    int     rc;

    if (smb_flush_required == 0) {
        rc = smbsr_encode_empty_result(sr);
        return ((rc == 0) ? SDRC_SUCCESS : SDRC_ERROR);
    }

    if (sr->smb_fid != 0xffff) {
        smbsr_lookup_file(sr);
        if (sr->fid_ofile == NULL) {
            smbsr_error(sr, NT_STATUS_INVALID_HANDLE,
                ERRDOS, ERRbadfid);
            return (SDRC_ERROR);
        }
        smb_ofile_flush(sr, sr->fid_ofile);
    } else {
        flist = &sr->tid_tree->t_ofile_list;
        smb_llist_enter(flist, RW_READER);
        file = smb_llist_head(flist);
        while (file) {
            mutex_enter(&file->f_mutex);
            smb_ofile_flush(sr, file);
            mutex_exit(&file->f_mutex);
            file = smb_llist_next(flist, file);
        }
        smb_llist_exit(flist);
    }

    rc = smbsr_encode_empty_result(sr);
    return ((rc == 0) ? SDRC_SUCCESS : SDRC_ERROR);
}