dir.c

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/*
 *   fs/cifs/dir.c
 *
 *   vfs operations that deal with dentries
 *
 *   Copyright (C) International Business Machines  Corp., 2002,2009
 *   Author(s): Steve French ([email protected])
 *
 *   This library is free software; you can redistribute it and/or modify
 *   it under the terms of the GNU Lesser General Public License as published
 *   by the Free Software Foundation; either version 2.1 of the License, or
 *   (at your option) any later version.
 *
 *   This library 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 Lesser General Public License for more details.
 *
 *   You should have received a copy of the GNU Lesser General Public License
 *   along with this library; if not, write to the Free Software
 *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 */
#include <linux/fs.h>
#include <linux/stat.h>
#include <linux/slab.h>
#include <linux/namei.h>
#include <linux/mount.h>
#include <linux/file.h>
#include "cifsfs.h"
#include "cifspdu.h"
#include "cifsglob.h"
#include "cifsproto.h"
#include "cifs_debug.h"
#include "cifs_fs_sb.h"

static void
renew_parental_timestamps(struct dentry *direntry)
{
    /* BB check if there is a way to get the kernel to do this or if we
       really need this */
    do {
        direntry->d_time = jiffies;
        direntry = direntry->d_parent;
    } while (!IS_ROOT(direntry));
}

/* Note: caller must free return buffer */
char *
build_path_from_dentry(struct dentry *direntry)
{
    struct dentry *temp;
    int namelen;
    int dfsplen;
    char *full_path;
    char dirsep;
    struct cifs_sb_info *cifs_sb = CIFS_SB(direntry->d_sb);
    struct cifs_tcon *tcon = cifs_sb_master_tcon(cifs_sb);
    unsigned seq;

    dirsep = CIFS_DIR_SEP(cifs_sb);
    if (tcon->Flags & SMB_SHARE_IS_IN_DFS)
        dfsplen = strnlen(tcon->treeName, MAX_TREE_SIZE + 1);
    else
        dfsplen = 0;
cifs_bp_rename_retry:
    namelen = dfsplen;
    seq = read_seqbegin(&rename_lock);
    rcu_read_lock();
    for (temp = direntry; !IS_ROOT(temp);) {
        namelen += (1 + temp->d_name.len);
        temp = temp->d_parent;
        if (temp == NULL) {
            cERROR(1, "corrupt dentry");
            rcu_read_unlock();
            return NULL;
        }
    }
    rcu_read_unlock();

    full_path = kmalloc(namelen+1, GFP_KERNEL);
    if (full_path == NULL)
        return full_path;
    full_path[namelen] = 0; /* trailing null */
    rcu_read_lock();
    for (temp = direntry; !IS_ROOT(temp);) {
        spin_lock(&temp->d_lock);
        namelen -= 1 + temp->d_name.len;
        if (namelen < 0) {
            spin_unlock(&temp->d_lock);
            break;
        } else {
            full_path[namelen] = dirsep;
            strncpy(full_path + namelen + 1, temp->d_name.name,
                temp->d_name.len);
            cFYI(0, "name: %s", full_path + namelen);
        }
        spin_unlock(&temp->d_lock);
        temp = temp->d_parent;
        if (temp == NULL) {
            cERROR(1, "corrupt dentry");
            rcu_read_unlock();
            kfree(full_path);
            return NULL;
        }
    }
    rcu_read_unlock();
    if (namelen != dfsplen || read_seqretry(&rename_lock, seq)) {
        cFYI(1, "did not end path lookup where expected. namelen=%d "
            "dfsplen=%d", namelen, dfsplen);
        /* presumably this is only possible if racing with a rename
        of one of the parent directories  (we can not lock the dentries
        above us to prevent this, but retrying should be harmless) */
        kfree(full_path);
        goto cifs_bp_rename_retry;
    }
    /* DIR_SEP already set for byte  0 / vs \ but not for
       subsequent slashes in prepath which currently must
       be entered the right way - not sure if there is an alternative
       since the '\' is a valid posix character so we can not switch
       those safely to '/' if any are found in the middle of the prepath */
    /* BB test paths to Windows with '/' in the midst of prepath */

    if (dfsplen) {
        strncpy(full_path, tcon->treeName, dfsplen);
        if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_POSIX_PATHS) {
            int i;
            for (i = 0; i < dfsplen; i++) {
                if (full_path[i] == '\\')
                    full_path[i] = '/';
            }
        }
    }
    return full_path;
}

/*
 * Don't allow the separator character in a path component.
 * The VFS will not allow "/", but "\" is allowed by posix.
 */
static int
check_name(struct dentry *direntry)
{
    struct cifs_sb_info *cifs_sb = CIFS_SB(direntry->d_sb);
    int i;

    if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_POSIX_PATHS)) {
        for (i = 0; i < direntry->d_name.len; i++) {
            if (direntry->d_name.name[i] == '\\') {
                cFYI(1, "Invalid file name");
                return -EINVAL;
            }
        }
    }
    return 0;
}


/* Inode operations in similar order to how they appear in Linux file fs.h */

static int
cifs_do_create(struct inode *inode, struct dentry *direntry, unsigned int xid,
           struct tcon_link *tlink, unsigned oflags, umode_t mode,
           __u32 *oplock, struct cifs_fid *fid, int *created)
{
    int rc = -ENOENT;
    int create_options = CREATE_NOT_DIR;
    int desired_access;
    struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
    struct cifs_tcon *tcon = tlink_tcon(tlink);
    char *full_path = NULL;
    FILE_ALL_INFO *buf = NULL;
    struct inode *newinode = NULL;
    int disposition;
    struct TCP_Server_Info *server = tcon->ses->server;

    *oplock = 0;
    if (tcon->ses->server->oplocks)
        *oplock = REQ_OPLOCK;

    full_path = build_path_from_dentry(direntry);
    if (full_path == NULL) {
        rc = -ENOMEM;
        goto out;
    }

    if (tcon->unix_ext && cap_unix(tcon->ses) && !tcon->broken_posix_open &&
        (CIFS_UNIX_POSIX_PATH_OPS_CAP &
            le64_to_cpu(tcon->fsUnixInfo.Capability))) {
        rc = cifs_posix_open(full_path, &newinode, inode->i_sb, mode,
                     oflags, oplock, &fid->netfid, xid);
        switch (rc) {
        case 0:
            if (newinode == NULL) {
                /* query inode info */
                goto cifs_create_get_file_info;
            }

            if (!S_ISREG(newinode->i_mode)) {
                /*
                 * The server may allow us to open things like
                 * FIFOs, but the client isn't set up to deal
                 * with that. If it's not a regular file, just
                 * close it and proceed as if it were a normal
                 * lookup.
                 */
                CIFSSMBClose(xid, tcon, fid->netfid);
                goto cifs_create_get_file_info;
            }
            /* success, no need to query */
            goto cifs_create_set_dentry;

        case -ENOENT:
            goto cifs_create_get_file_info;

        case -EIO:
        case -EINVAL:
            /*
             * EIO could indicate that (posix open) operation is not
             * supported, despite what server claimed in capability
             * negotiation.
             *
             * POSIX open in samba versions 3.3.1 and earlier could
             * incorrectly fail with invalid parameter.
             */
            tcon->broken_posix_open = true;
            break;

        case -EREMOTE:
        case -EOPNOTSUPP:
            /*
             * EREMOTE indicates DFS junction, which is not handled
             * in posix open.  If either that or op not supported
             * returned, follow the normal lookup.
             */
            break;

        default:
            goto out;
        }
        /*
         * fallthrough to retry, using older open call, this is case
         * where server does not support this SMB level, and falsely
         * claims capability (also get here for DFS case which should be
         * rare for path not covered on files)
         */
    }

    desired_access = 0;
    if (OPEN_FMODE(oflags) & FMODE_READ)
        desired_access |= GENERIC_READ; /* is this too little? */
    if (OPEN_FMODE(oflags) & FMODE_WRITE)
        desired_access |= GENERIC_WRITE;

    disposition = FILE_OVERWRITE_IF;
    if ((oflags & (O_CREAT | O_EXCL)) == (O_CREAT | O_EXCL))
        disposition = FILE_CREATE;
    else if ((oflags & (O_CREAT | O_TRUNC)) == (O_CREAT | O_TRUNC))
        disposition = FILE_OVERWRITE_IF;
    else if ((oflags & O_CREAT) == O_CREAT)
        disposition = FILE_OPEN_IF;
    else
        cFYI(1, "Create flag not set in create function");

    /*
     * BB add processing to set equivalent of mode - e.g. via CreateX with
     * ACLs
     */

    if (!server->ops->open) {
        rc = -ENOSYS;
        goto out;
    }

    buf = kmalloc(sizeof(FILE_ALL_INFO), GFP_KERNEL);
    if (buf == NULL) {
        rc = -ENOMEM;
        goto out;
    }

    /*
     * if we're not using unix extensions, see if we need to set
     * ATTR_READONLY on the create call
     */
    if (!tcon->unix_ext && (mode & S_IWUGO) == 0)
        create_options |= CREATE_OPTION_READONLY;

    if (backup_cred(cifs_sb))
        create_options |= CREATE_OPEN_BACKUP_INTENT;

    rc = server->ops->open(xid, tcon, full_path, disposition,
                   desired_access, create_options, fid, oplock,
                   buf, cifs_sb);
    if (rc) {
        cFYI(1, "cifs_create returned 0x%x", rc);
        goto out;
    }

    /*
     * If Open reported that we actually created a file then we now have to
     * set the mode if possible.
     */
    if ((tcon->unix_ext) && (*oplock & CIFS_CREATE_ACTION)) {
        struct cifs_unix_set_info_args args = {
                .mode   = mode,
                .ctime  = NO_CHANGE_64,
                .atime  = NO_CHANGE_64,
                .mtime  = NO_CHANGE_64,
                .device = 0,
        };

        *created |= FILE_CREATED;
        if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SET_UID) {
            args.uid = (__u64) current_fsuid();
            if (inode->i_mode & S_ISGID)
                args.gid = (__u64) inode->i_gid;
            else
                args.gid = (__u64) current_fsgid();
        } else {
            args.uid = NO_CHANGE_64;
            args.gid = NO_CHANGE_64;
        }
        CIFSSMBUnixSetFileInfo(xid, tcon, &args, fid->netfid,
                       current->tgid);
    } else {
        /*
         * BB implement mode setting via Windows security
         * descriptors e.g.
         */
        /* CIFSSMBWinSetPerms(xid,tcon,path,mode,-1,-1,nls);*/

        /* Could set r/o dos attribute if mode & 0222 == 0 */
    }

cifs_create_get_file_info:
    /* server might mask mode so we have to query for it */
    if (tcon->unix_ext)
        rc = cifs_get_inode_info_unix(&newinode, full_path, inode->i_sb,
                          xid);
    else {
        rc = cifs_get_inode_info(&newinode, full_path, buf, inode->i_sb,
                     xid, &fid->netfid);
        if (newinode) {
            if (server->ops->set_lease_key)
                server->ops->set_lease_key(newinode, fid);
            if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_DYNPERM)
                newinode->i_mode = mode;
            if ((*oplock & CIFS_CREATE_ACTION) &&
                (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SET_UID)) {
                newinode->i_uid = current_fsuid();
                if (inode->i_mode & S_ISGID)
                    newinode->i_gid = inode->i_gid;
                else
                    newinode->i_gid = current_fsgid();
            }
        }
    }

cifs_create_set_dentry:
    if (rc != 0) {
        cFYI(1, "Create worked, get_inode_info failed rc = %d", rc);
        if (server->ops->close)
            server->ops->close(xid, tcon, fid);
        goto out;
    }
    d_drop(direntry);
    d_add(direntry, newinode);

out:
    kfree(buf);
    kfree(full_path);
    return rc;
}

int
cifs_atomic_open(struct inode *inode, struct dentry *direntry,
         struct file *file, unsigned oflags, umode_t mode,
         int *opened)
{
    int rc;
    unsigned int xid;
    struct tcon_link *tlink;
    struct cifs_tcon *tcon;
    struct TCP_Server_Info *server;
    struct cifs_fid fid;
    struct cifs_pending_open open;
    __u32 oplock;
    struct cifsFileInfo *file_info;

    /*
     * Posix open is only called (at lookup time) for file create now. For
     * opens (rather than creates), because we do not know if it is a file
     * or directory yet, and current Samba no longer allows us to do posix
     * open on dirs, we could end up wasting an open call on what turns out
     * to be a dir. For file opens, we wait to call posix open till
     * cifs_open.  It could be added to atomic_open in the future but the
     * performance tradeoff of the extra network request when EISDIR or
     * EACCES is returned would have to be weighed against the 50% reduction
     * in network traffic in the other paths.
     */
    if (!(oflags & O_CREAT)) {
        struct dentry *res;

        /*
         * Check for hashed negative dentry. We have already revalidated
         * the dentry and it is fine. No need to perform another lookup.
         */
        if (!d_unhashed(direntry))
            return -ENOENT;

        res = cifs_lookup(inode, direntry, 0);
        if (IS_ERR(res))
            return PTR_ERR(res);

        return finish_no_open(file, res);
    }

    rc = check_name(direntry);
    if (rc)
        return rc;

    xid = get_xid();

    cFYI(1, "parent inode = 0x%p name is: %s and dentry = 0x%p",
         inode, direntry->d_name.name, direntry);

    tlink = cifs_sb_tlink(CIFS_SB(inode->i_sb));
    if (IS_ERR(tlink))
        goto out_free_xid;

    tcon = tlink_tcon(tlink);
    server = tcon->ses->server;

    if (server->ops->new_lease_key)
        server->ops->new_lease_key(&fid);

    cifs_add_pending_open(&fid, tlink, &open);

    rc = cifs_do_create(inode, direntry, xid, tlink, oflags, mode,
                &oplock, &fid, opened);

    if (rc) {
        cifs_del_pending_open(&open);
        goto out;
    }

    rc = finish_open(file, direntry, generic_file_open, opened);
    if (rc) {
        if (server->ops->close)
            server->ops->close(xid, tcon, &fid);
        cifs_del_pending_open(&open);
        goto out;
    }

    file_info = cifs_new_fileinfo(&fid, file, tlink, oplock);
    if (file_info == NULL) {
        if (server->ops->close)
            server->ops->close(xid, tcon, &fid);
        cifs_del_pending_open(&open);
        rc = -ENOMEM;
    }

out:
    cifs_put_tlink(tlink);
out_free_xid:
    free_xid(xid);
    return rc;
}

int cifs_create(struct inode *inode, struct dentry *direntry, umode_t mode,
        bool excl)
{
    int rc;
    unsigned int xid = get_xid();
    /*
     * BB below access is probably too much for mknod to request
     *    but we have to do query and setpathinfo so requesting
     *    less could fail (unless we want to request getatr and setatr
     *    permissions (only).  At least for POSIX we do not have to
     *    request so much.
     */
    unsigned oflags = O_EXCL | O_CREAT | O_RDWR;
    struct tcon_link *tlink;
    struct cifs_tcon *tcon;
    struct TCP_Server_Info *server;
    struct cifs_fid fid;
    __u32 oplock;
    int created = FILE_CREATED;

    cFYI(1, "cifs_create parent inode = 0x%p name is: %s and dentry = 0x%p",
         inode, direntry->d_name.name, direntry);

    tlink = cifs_sb_tlink(CIFS_SB(inode->i_sb));
    rc = PTR_ERR(tlink);
    if (IS_ERR(tlink))
        goto out_free_xid;

    tcon = tlink_tcon(tlink);
    server = tcon->ses->server;

    if (server->ops->new_lease_key)
        server->ops->new_lease_key(&fid);

    rc = cifs_do_create(inode, direntry, xid, tlink, oflags, mode,
                &oplock, &fid, &created);
    if (!rc && server->ops->close)
        server->ops->close(xid, tcon, &fid);

    cifs_put_tlink(tlink);
out_free_xid:
    free_xid(xid);
    return rc;
}

int cifs_mknod(struct inode *inode, struct dentry *direntry, umode_t mode,
        dev_t device_number)
{
    int rc = -EPERM;
    unsigned int xid;
    int create_options = CREATE_NOT_DIR | CREATE_OPTION_SPECIAL;
    struct cifs_sb_info *cifs_sb;
    struct tcon_link *tlink;
    struct cifs_tcon *pTcon;
    struct cifs_io_parms io_parms;
    char *full_path = NULL;
    struct inode *newinode = NULL;
    int oplock = 0;
    u16 fileHandle;
    FILE_ALL_INFO *buf = NULL;
    unsigned int bytes_written;
    struct win_dev *pdev;

    if (!old_valid_dev(device_number))
        return -EINVAL;

    cifs_sb = CIFS_SB(inode->i_sb);
    tlink = cifs_sb_tlink(cifs_sb);
    if (IS_ERR(tlink))
        return PTR_ERR(tlink);

    pTcon = tlink_tcon(tlink);

    xid = get_xid();

    full_path = build_path_from_dentry(direntry);
    if (full_path == NULL) {
        rc = -ENOMEM;
        goto mknod_out;
    }

    if (pTcon->unix_ext) {
        struct cifs_unix_set_info_args args = {
            .mode   = mode & ~current_umask(),
            .ctime  = NO_CHANGE_64,
            .atime  = NO_CHANGE_64,
            .mtime  = NO_CHANGE_64,
            .device = device_number,
        };
        if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SET_UID) {
            args.uid = (__u64) current_fsuid();
            args.gid = (__u64) current_fsgid();
        } else {
            args.uid = NO_CHANGE_64;
            args.gid = NO_CHANGE_64;
        }
        rc = CIFSSMBUnixSetPathInfo(xid, pTcon, full_path, &args,
                        cifs_sb->local_nls,
                        cifs_sb->mnt_cifs_flags &
                        CIFS_MOUNT_MAP_SPECIAL_CHR);
        if (rc)
            goto mknod_out;

        rc = cifs_get_inode_info_unix(&newinode, full_path,
                        inode->i_sb, xid);

        if (rc == 0)
            d_instantiate(direntry, newinode);
        goto mknod_out;
    }

    if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_UNX_EMUL))
        goto mknod_out;


    cFYI(1, "sfu compat create special file");

    buf = kmalloc(sizeof(FILE_ALL_INFO), GFP_KERNEL);
    if (buf == NULL) {
        kfree(full_path);
        rc = -ENOMEM;
        free_xid(xid);
        return rc;
    }

    if (backup_cred(cifs_sb))
        create_options |= CREATE_OPEN_BACKUP_INTENT;

    rc = CIFSSMBOpen(xid, pTcon, full_path, FILE_CREATE,
             GENERIC_WRITE, create_options,
             &fileHandle, &oplock, buf, cifs_sb->local_nls,
             cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR);
    if (rc)
        goto mknod_out;

    /* BB Do not bother to decode buf since no local inode yet to put
     * timestamps in, but we can reuse it safely */

    pdev = (struct win_dev *)buf;
    io_parms.netfid = fileHandle;
    io_parms.pid = current->tgid;
    io_parms.tcon = pTcon;
    io_parms.offset = 0;
    io_parms.length = sizeof(struct win_dev);
    if (S_ISCHR(mode)) {
        memcpy(pdev->type, "IntxCHR", 8);
        pdev->major =
              cpu_to_le64(MAJOR(device_number));
        pdev->minor =
              cpu_to_le64(MINOR(device_number));
        rc = CIFSSMBWrite(xid, &io_parms,
            &bytes_written, (char *)pdev,
            NULL, 0);
    } else if (S_ISBLK(mode)) {
        memcpy(pdev->type, "IntxBLK", 8);
        pdev->major =
              cpu_to_le64(MAJOR(device_number));
        pdev->minor =
              cpu_to_le64(MINOR(device_number));
        rc = CIFSSMBWrite(xid, &io_parms,
            &bytes_written, (char *)pdev,
            NULL, 0);
    } /* else if (S_ISFIFO) */
    CIFSSMBClose(xid, pTcon, fileHandle);
    d_drop(direntry);

    /* FIXME: add code here to set EAs */

mknod_out:
    kfree(full_path);
    kfree(buf);
    free_xid(xid);
    cifs_put_tlink(tlink);
    return rc;
}

struct dentry *
cifs_lookup(struct inode *parent_dir_inode, struct dentry *direntry,
        unsigned int flags)
{
    unsigned int xid;
    int rc = 0; /* to get around spurious gcc warning, set to zero here */
    struct cifs_sb_info *cifs_sb;
    struct tcon_link *tlink;
    struct cifs_tcon *pTcon;
    struct inode *newInode = NULL;
    char *full_path = NULL;

    xid = get_xid();

    cFYI(1, "parent inode = 0x%p name is: %s and dentry = 0x%p",
          parent_dir_inode, direntry->d_name.name, direntry);

    /* check whether path exists */

    cifs_sb = CIFS_SB(parent_dir_inode->i_sb);
    tlink = cifs_sb_tlink(cifs_sb);
    if (IS_ERR(tlink)) {
        free_xid(xid);
        return (struct dentry *)tlink;
    }
    pTcon = tlink_tcon(tlink);

    rc = check_name(direntry);
    if (rc)
        goto lookup_out;

    /* can not grab the rename sem here since it would
    deadlock in the cases (beginning of sys_rename itself)
    in which we already have the sb rename sem */
    full_path = build_path_from_dentry(direntry);
    if (full_path == NULL) {
        rc = -ENOMEM;
        goto lookup_out;
    }

    if (direntry->d_inode != NULL) {
        cFYI(1, "non-NULL inode in lookup");
    } else {
        cFYI(1, "NULL inode in lookup");
    }
    cFYI(1, "Full path: %s inode = 0x%p", full_path, direntry->d_inode);

    if (pTcon->unix_ext) {
        rc = cifs_get_inode_info_unix(&newInode, full_path,
                          parent_dir_inode->i_sb, xid);
    } else {
        rc = cifs_get_inode_info(&newInode, full_path, NULL,
                parent_dir_inode->i_sb, xid, NULL);
    }

    if ((rc == 0) && (newInode != NULL)) {
        d_add(direntry, newInode);
        /* since paths are not looked up by component - the parent
           directories are presumed to be good here */
        renew_parental_timestamps(direntry);

    } else if (rc == -ENOENT) {
        rc = 0;
        direntry->d_time = jiffies;
        d_add(direntry, NULL);
    /*  if it was once a directory (but how can we tell?) we could do
        shrink_dcache_parent(direntry); */
    } else if (rc != -EACCES) {
        cERROR(1, "Unexpected lookup error %d", rc);
        /* We special case check for Access Denied - since that
        is a common return code */
    }

lookup_out:
    kfree(full_path);
    cifs_put_tlink(tlink);
    free_xid(xid);
    return ERR_PTR(rc);
}

static int
cifs_d_revalidate(struct dentry *direntry, unsigned int flags)
{
    if (flags & LOOKUP_RCU)
        return -ECHILD;

    if (direntry->d_inode) {
        if (cifs_revalidate_dentry(direntry))
            return 0;
        else {
            /*
             * If the inode wasn't known to be a dfs entry when
             * the dentry was instantiated, such as when created
             * via ->readdir(), it needs to be set now since the
             * attributes will have been updated by
             * cifs_revalidate_dentry().
             */
            if (IS_AUTOMOUNT(direntry->d_inode) &&
               !(direntry->d_flags & DCACHE_NEED_AUTOMOUNT)) {
                spin_lock(&direntry->d_lock);
                direntry->d_flags |= DCACHE_NEED_AUTOMOUNT;
                spin_unlock(&direntry->d_lock);
            }

            return 1;
        }
    }

    /*
     * This may be nfsd (or something), anyway, we can't see the
     * intent of this. So, since this can be for creation, drop it.
     */
    if (!flags)
        return 0;

    /*
     * Drop the negative dentry, in order to make sure to use the
     * case sensitive name which is specified by user if this is
     * for creation.
     */
    if (flags & (LOOKUP_CREATE | LOOKUP_RENAME_TARGET))
        return 0;

    if (time_after(jiffies, direntry->d_time + HZ) || !lookupCacheEnabled)
        return 0;

    return 1;
}

/* static int cifs_d_delete(struct dentry *direntry)
{
    int rc = 0;

    cFYI(1, "In cifs d_delete, name = %s", direntry->d_name.name);

    return rc;
}     */

const struct dentry_operations cifs_dentry_ops = {
    .d_revalidate = cifs_d_revalidate,
    .d_automount = cifs_dfs_d_automount,
/* d_delete:       cifs_d_delete,      */ /* not needed except for debugging */
};

static int cifs_ci_hash(const struct dentry *dentry, const struct inode *inode,
        struct qstr *q)
{
    struct nls_table *codepage = CIFS_SB(dentry->d_sb)->local_nls;
    unsigned long hash;
    int i;

    hash = init_name_hash();
    for (i = 0; i < q->len; i++)
        hash = partial_name_hash(nls_tolower(codepage, q->name[i]),
                     hash);
    q->hash = end_name_hash(hash);

    return 0;
}

static int cifs_ci_compare(const struct dentry *parent,
        const struct inode *pinode,
        const struct dentry *dentry, const struct inode *inode,
        unsigned int len, const char *str, const struct qstr *name)
{
    struct nls_table *codepage = CIFS_SB(pinode->i_sb)->local_nls;

    if ((name->len == len) &&
        (nls_strnicmp(codepage, name->name, str, len) == 0))
        return 0;
    return 1;
}

const struct dentry_operations cifs_ci_dentry_ops = {
    .d_revalidate = cifs_d_revalidate,
    .d_hash = cifs_ci_hash,
    .d_compare = cifs_ci_compare,
    .d_automount = cifs_dfs_d_automount,
};