path: root/src/VBox/Additions/linux/sharedfolders/dirops.c

/* $Id: dirops.c $ */
/** @file
 * vboxsf - VBox Linux Shared Folders VFS, directory inode and file operations.
 */

/*
 * Copyright (C) 2006-2019 Oracle Corporation
 *
 * Permission is hereby granted, free of charge, to any person
 * obtaining a copy of this software and associated documentation
 * files (the "Software"), to deal in the Software without
 * restriction, including without limitation the rights to use,
 * copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following
 * conditions:
 *
 * The above copyright notice and this permission notice shall be
 * included in all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
 * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 * NONINFRINGEMENT.  IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
 * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
 * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
 * OTHER DEALINGS IN THE SOFTWARE.
 */

#include "vfsmod.h"
#include <iprt/err.h>

/**
 * Open a directory. Read the complete content into a buffer.
 *
 * @param inode     inode
 * @param file      file
 * @returns 0 on success, Linux error code otherwise
 */
static int sf_dir_open(struct inode *inode, struct file *file)
{
	int rc;
	int err;
	struct sf_glob_info *sf_g = GET_GLOB_INFO(inode->i_sb);
	struct sf_dir_info *sf_d;
	struct sf_inode_info *sf_i = GET_INODE_INFO(inode);
	SHFLCREATEPARMS params;

	TRACE();
	BUG_ON(!sf_g);
	BUG_ON(!sf_i);

	if (file->private_data) {
		LogFunc(("sf_dir_open() called on already opened directory '%s'\n", sf_i->path->String.utf8));
		return 0;
	}

	sf_d = sf_dir_info_alloc();
	if (!sf_d) {
		LogRelFunc(("could not allocate directory info for '%s'\n",
			    sf_i->path->String.utf8));
		return -ENOMEM;
	}

	RT_ZERO(params);
	params.Handle = SHFL_HANDLE_NIL;
	params.CreateFlags = 0
	    | SHFL_CF_DIRECTORY
	    | SHFL_CF_ACT_OPEN_IF_EXISTS
	    | SHFL_CF_ACT_FAIL_IF_NEW | SHFL_CF_ACCESS_READ;

	LogFunc(("sf_dir_open(): calling VbglR0SfCreate, folder %s, flags %#x\n", sf_i->path->String.utf8, params.CreateFlags));
	rc = VbglR0SfCreate(&client_handle, &sf_g->map, sf_i->path, &params);
	if (RT_SUCCESS(rc)) {
		if (params.Result == SHFL_FILE_EXISTS) {
			err = sf_dir_read_all(sf_g, sf_i, sf_d, params.Handle);
			if (!err)
				file->private_data = sf_d;
		} else
			err = -ENOENT;

		rc = VbglR0SfClose(&client_handle, &sf_g->map, params.Handle);
		if (RT_FAILURE(rc))
			LogFunc(("sf_dir_open(): VbglR0SfClose(%s) after err=%d failed rc=%Rrc\n", sf_i->path->String.utf8, err, rc));
	} else
		err = -EPERM;

	if (err)
		sf_dir_info_free(sf_d);

	return err;
}

/**
 * This is called when reference count of [file] goes to zero. Notify
 * the host that it can free whatever is associated with this directory
 * and deallocate our own internal buffers
 *
 * @param inode     inode
 * @param file      file
 * returns 0 on success, Linux error code otherwise
 */
static int sf_dir_release(struct inode *inode, struct file *file)
{
	TRACE();

	if (file->private_data)
		sf_dir_info_free(file->private_data);

	return 0;
}

/**
 * Translate RTFMODE into DT_xxx (in conjunction to rtDirType())
 * @param fMode     file mode
 * returns d_type
 */
static int sf_get_d_type(RTFMODE fMode)
{
	int d_type;
	switch (fMode & RTFS_TYPE_MASK) {
	case RTFS_TYPE_FIFO:
		d_type = DT_FIFO;
		break;
	case RTFS_TYPE_DEV_CHAR:
		d_type = DT_CHR;
		break;
	case RTFS_TYPE_DIRECTORY:
		d_type = DT_DIR;
		break;
	case RTFS_TYPE_DEV_BLOCK:
		d_type = DT_BLK;
		break;
	case RTFS_TYPE_FILE:
		d_type = DT_REG;
		break;
	case RTFS_TYPE_SYMLINK:
		d_type = DT_LNK;
		break;
	case RTFS_TYPE_SOCKET:
		d_type = DT_SOCK;
		break;
	case RTFS_TYPE_WHITEOUT:
		d_type = DT_WHT;
		break;
	default:
		d_type = DT_UNKNOWN;
		break;
	}
	return d_type;
}

/**
 * Extract element ([dir]->f_pos) from the directory [dir] into [d_name].
 *
 * @returns 0 for success, 1 for end reached, Linux error code otherwise.
 */
static int sf_getdent(struct file *dir, char d_name[NAME_MAX], int *d_type)
{
	loff_t cur;
	struct sf_glob_info *sf_g;
	struct sf_dir_info *sf_d;
	struct sf_inode_info *sf_i;
	struct inode *inode;
	struct list_head *pos, *list;

	TRACE();

	inode = GET_F_DENTRY(dir)->d_inode;
	sf_i = GET_INODE_INFO(inode);
	sf_g = GET_GLOB_INFO(inode->i_sb);
	sf_d = dir->private_data;

	BUG_ON(!sf_g);
	BUG_ON(!sf_d);
	BUG_ON(!sf_i);

	if (sf_i->force_reread) {
		int rc;
		int err;
		SHFLCREATEPARMS params;

		RT_ZERO(params);
		params.Handle = SHFL_HANDLE_NIL;
		params.CreateFlags = 0
		    | SHFL_CF_DIRECTORY
		    | SHFL_CF_ACT_OPEN_IF_EXISTS
		    | SHFL_CF_ACT_FAIL_IF_NEW | SHFL_CF_ACCESS_READ;

		LogFunc(("sf_getdent: calling VbglR0SfCreate, folder %s, flags %#x\n", sf_i->path->String.utf8, params.CreateFlags));
		rc = VbglR0SfCreate(&client_handle, &sf_g->map, sf_i->path,
				    &params);
		if (RT_FAILURE(rc)) {
			LogFunc(("VbglR0SfCreate(%s) failed rc=%Rrc\n",
				 sf_i->path->String.utf8, rc));
			return -EPERM;
		}

		if (params.Result != SHFL_FILE_EXISTS) {
			LogFunc(("directory %s does not exist\n",
				 sf_i->path->String.utf8));
			sf_dir_info_free(sf_d);
			return -ENOENT;
		}

		sf_dir_info_empty(sf_d);
		err = sf_dir_read_all(sf_g, sf_i, sf_d, params.Handle);
		rc = VbglR0SfClose(&client_handle, &sf_g->map, params.Handle);
		if (RT_FAILURE(rc))
			LogFunc(("VbglR0SfClose(%s) failed rc=%Rrc\n",
				 sf_i->path->String.utf8, rc));
		if (err)
			return err;

		sf_i->force_reread = 0;
	}

	cur = 0;
	list = &sf_d->info_list;
	list_for_each(pos, list) {
		struct sf_dir_buf *b;
		SHFLDIRINFO *info;
		loff_t i;

		b = list_entry(pos, struct sf_dir_buf, head);
		if (dir->f_pos >= cur + b->cEntries) {
			cur += b->cEntries;
			continue;
		}

		for (i = 0, info = b->buf; i < dir->f_pos - cur; ++i) {
			size_t size;

			size =
			    offsetof(SHFLDIRINFO,
				     name.String) + info->name.u16Size;
			info = (SHFLDIRINFO *) ((uintptr_t) info + size);
		}

		*d_type = sf_get_d_type(info->Info.Attr.fMode);

		return sf_nlscpy(sf_g, d_name, NAME_MAX,
				 info->name.String.utf8, info->name.u16Length);
	}

	return 1;
}

/**
 * This is called when vfs wants to populate internal buffers with
 * directory [dir]s contents. [opaque] is an argument to the
 * [filldir]. [filldir] magically modifies it's argument - [opaque]
 * and takes following additional arguments (which i in turn get from
 * the host via sf_getdent):
 *
 * name : name of the entry (i must also supply it's length huh?)
 * type : type of the entry (FILE | DIR | etc) (i ellect to use DT_UNKNOWN)
 * pos : position/index of the entry
 * ino : inode number of the entry (i fake those)
 *
 * [dir] contains:
 * f_pos : cursor into the directory listing
 * private_data : mean of communication with the host side
 *
 * Extract elements from the directory listing (incrementing f_pos
 * along the way) and feed them to [filldir] until:
 *
 * a. there are no more entries (i.e. sf_getdent set done to 1)
 * b. failure to compute fake inode number
 * c. filldir returns an error (see comment on that)
 */
#if LINUX_VERSION_CODE >= KERNEL_VERSION(3, 11, 0)
static int sf_dir_iterate(struct file *dir, struct dir_context *ctx)
#else
static int sf_dir_read(struct file *dir, void *opaque, filldir_t filldir)
#endif
{
	TRACE();
	for (;;) {
		int err;
		ino_t fake_ino;
		loff_t sanity;
		char d_name[NAME_MAX];
		int d_type = DT_UNKNOWN;

		err = sf_getdent(dir, d_name, &d_type);
		switch (err) {
		case 1:
			return 0;

		case 0:
			break;

		case -1:
		default:
			/* skip erroneous entry and proceed */
			LogFunc(("sf_getdent error %d\n", err));
			dir->f_pos += 1;
#if LINUX_VERSION_CODE >= KERNEL_VERSION(3, 11, 0)
			ctx->pos += 1;
#endif
			continue;
		}

		/* d_name now contains a valid entry name */

#if LINUX_VERSION_CODE >= KERNEL_VERSION(3, 11, 0)
		sanity = ctx->pos + 0xbeef;
#else
		sanity = dir->f_pos + 0xbeef;
#endif
		fake_ino = sanity;
		if (sanity - fake_ino) {
			LogRelFunc(("can not compute ino\n"));
			return -EINVAL;
		}
#if LINUX_VERSION_CODE >= KERNEL_VERSION(3, 11, 0)
		if (!dir_emit(ctx, d_name, strlen(d_name), fake_ino, d_type)) {
			LogFunc(("dir_emit failed\n"));
			return 0;
		}
#else
		err =
		    filldir(opaque, d_name, strlen(d_name), dir->f_pos,
			    fake_ino, d_type);
		if (err) {
			LogFunc(("filldir returned error %d\n", err));
			/* Rely on the fact that filldir returns error
			   only when it runs out of space in opaque */
			return 0;
		}
#endif

		dir->f_pos += 1;
#if LINUX_VERSION_CODE >= KERNEL_VERSION(3, 11, 0)
		ctx->pos += 1;
#endif
	}

	BUG();
}

struct file_operations sf_dir_fops = {
	.open = sf_dir_open,
#if LINUX_VERSION_CODE >= KERNEL_VERSION(3, 11, 0)
	.iterate = sf_dir_iterate,
#else
	.readdir = sf_dir_read,
#endif
	.release = sf_dir_release,
	.read = generic_read_dir
#if LINUX_VERSION_CODE >= KERNEL_VERSION(2, 6, 37)
	, .llseek = generic_file_llseek
#endif
};

/* iops */

/**
 * This is called when vfs failed to locate dentry in the cache. The
 * job of this function is to allocate inode and link it to dentry.
 * [dentry] contains the name to be looked in the [parent] directory.
 * Failure to locate the name is not a "hard" error, in this case NULL
 * inode is added to [dentry] and vfs should proceed trying to create
 * the entry via other means. NULL(or "positive" pointer) ought to be
 * returned in case of success and "negative" pointer on error
 */
static struct dentry *sf_lookup(struct inode *parent, struct dentry *dentry
#if LINUX_VERSION_CODE >= KERNEL_VERSION(3, 6, 0)
				, unsigned int flags
#elif LINUX_VERSION_CODE >= KERNEL_VERSION(2, 6, 0)
				, struct nameidata *nd
#endif
    )
{
	int err;
	struct sf_inode_info *sf_i, *sf_new_i;
	struct sf_glob_info *sf_g;
	SHFLSTRING *path;
	struct inode *inode;
	ino_t ino;
	SHFLFSOBJINFO fsinfo;

	TRACE();
	sf_g = GET_GLOB_INFO(parent->i_sb);
	sf_i = GET_INODE_INFO(parent);

	BUG_ON(!sf_g);
	BUG_ON(!sf_i);

	err = sf_path_from_dentry(__func__, sf_g, sf_i, dentry, &path);
	if (err)
		goto fail0;

	err = sf_stat(__func__, sf_g, path, &fsinfo, 1);
	if (err) {
		if (err == -ENOENT) {
			/* -ENOENT: add NULL inode to dentry so it later can be
			   created via call to create/mkdir/open */
			kfree(path);
			inode = NULL;
		} else
			goto fail1;
	} else {
		sf_new_i = kmalloc(sizeof(*sf_new_i), GFP_KERNEL);
		if (!sf_new_i) {
			LogRelFunc(("could not allocate memory for new inode info\n"));
			err = -ENOMEM;
			goto fail1;
		}
		sf_new_i->handle = SHFL_HANDLE_NIL;
		sf_new_i->force_reread = 0;

		ino = iunique(parent->i_sb, 1);
#if LINUX_VERSION_CODE >= KERNEL_VERSION(2, 4, 25)
		inode = iget_locked(parent->i_sb, ino);
#else
		inode = iget(parent->i_sb, ino);
#endif
		if (!inode) {
			LogFunc(("iget failed\n"));
			err = -ENOMEM;	/* XXX: ??? */
			goto fail2;
		}

		SET_INODE_INFO(inode, sf_new_i);
		sf_init_inode(sf_g, inode, &fsinfo);
		sf_new_i->path = path;

#if LINUX_VERSION_CODE >= KERNEL_VERSION(2, 4, 25)
		unlock_new_inode(inode);
#endif
	}

	sf_i->force_restat = 0;
	dentry->d_time = jiffies;
#if LINUX_VERSION_CODE >= KERNEL_VERSION(2, 6, 38)
	d_set_d_op(dentry, &sf_dentry_ops);
#else
	dentry->d_op = &sf_dentry_ops;
#endif
	d_add(dentry, inode);
	return NULL;

 fail2:
	kfree(sf_new_i);

 fail1:
	kfree(path);

 fail0:
	return ERR_PTR(err);
}

/**
 * This should allocate memory for sf_inode_info, compute a unique inode
 * number, get an inode from vfs, initialize inode info, instantiate
 * dentry.
 *
 * @param parent        inode entry of the directory
 * @param dentry        directory cache entry
 * @param path          path name
 * @param info          file information
 * @param handle        handle
 * @returns 0 on success, Linux error code otherwise
 */
static int sf_instantiate(struct inode *parent, struct dentry *dentry,
			  SHFLSTRING * path, PSHFLFSOBJINFO info,
			  SHFLHANDLE handle)
{
	int err;
	ino_t ino;
	struct inode *inode;
	struct sf_inode_info *sf_new_i;
	struct sf_glob_info *sf_g = GET_GLOB_INFO(parent->i_sb);

	TRACE();
	BUG_ON(!sf_g);

	sf_new_i = kmalloc(sizeof(*sf_new_i), GFP_KERNEL);
	if (!sf_new_i) {
		LogRelFunc(("could not allocate inode info.\n"));
		err = -ENOMEM;
		goto fail0;
	}

	ino = iunique(parent->i_sb, 1);
#if LINUX_VERSION_CODE >= KERNEL_VERSION(2, 4, 25)
	inode = iget_locked(parent->i_sb, ino);
#else
	inode = iget(parent->i_sb, ino);
#endif
	if (!inode) {
		LogFunc(("iget failed\n"));
		err = -ENOMEM;
		goto fail1;
	}

	sf_init_inode(sf_g, inode, info);
	sf_new_i->path = path;
	SET_INODE_INFO(inode, sf_new_i);
	sf_new_i->force_restat = 1;
	sf_new_i->force_reread = 0;

	d_instantiate(dentry, inode);

#if LINUX_VERSION_CODE >= KERNEL_VERSION(2, 4, 25)
	unlock_new_inode(inode);
#endif

	/* Store this handle if we leave the handle open. */
	sf_new_i->handle = handle;
	return 0;

 fail1:
	kfree(sf_new_i);

 fail0:
	return err;

}

/**
 * Create a new regular file / directory.
 *
 * @param parent        inode of the directory
 * @param dentry        directory cache entry
 * @param mode          file mode
 * @param fDirectory    true if directory, false otherwise
 * @returns 0 on success, Linux error code otherwise
 */
static int sf_create_aux(struct inode *parent, struct dentry *dentry,
			 umode_t mode, int fDirectory)
{
	int rc, err;
	SHFLCREATEPARMS params;
	SHFLSTRING *path;
	struct sf_inode_info *sf_i = GET_INODE_INFO(parent);
	struct sf_glob_info *sf_g = GET_GLOB_INFO(parent->i_sb);

	TRACE();
	BUG_ON(!sf_i);
	BUG_ON(!sf_g);

	err = sf_path_from_dentry(__func__, sf_g, sf_i, dentry, &path);
	if (err)
		goto fail0;

	RT_ZERO(params);
	params.Handle = SHFL_HANDLE_NIL;
	params.CreateFlags = 0
	    | SHFL_CF_ACT_CREATE_IF_NEW
	    | SHFL_CF_ACT_FAIL_IF_EXISTS
	    | SHFL_CF_ACCESS_READWRITE | (fDirectory ? SHFL_CF_DIRECTORY : 0);
	params.Info.Attr.fMode = 0
	    | (fDirectory ? RTFS_TYPE_DIRECTORY : RTFS_TYPE_FILE)
	    | (mode & S_IRWXUGO);
	params.Info.Attr.enmAdditional = RTFSOBJATTRADD_NOTHING;

	LogFunc(("sf_create_aux: calling VbglR0SfCreate, folder %s, flags %#x\n", path->String.utf8, params.CreateFlags));
	rc = VbglR0SfCreate(&client_handle, &sf_g->map, path, &params);
	if (RT_FAILURE(rc)) {
		if (rc == VERR_WRITE_PROTECT) {
			err = -EROFS;
			goto fail1;
		}
		err = -EPROTO;
		LogFunc(("(%d): VbglR0SfCreate(%s) failed rc=%Rrc\n",
			 fDirectory, sf_i->path->String.utf8, rc));
		goto fail1;
	}

	if (params.Result != SHFL_FILE_CREATED) {
		err = -EPERM;
		LogFunc(("(%d): could not create file %s result=%d\n",
			 fDirectory, sf_i->path->String.utf8, params.Result));
		goto fail1;
	}

	err = sf_instantiate(parent, dentry, path, &params.Info,
			     fDirectory ? SHFL_HANDLE_NIL : params.Handle);
	if (err) {
		LogFunc(("(%d): could not instantiate dentry for %s err=%d\n",
			 fDirectory, sf_i->path->String.utf8, err));
		goto fail2;
	}

	/*
	 * Don't close this handle right now. We assume that the same file is
	 * opened with sf_reg_open() and later closed with sf_reg_close(). Save
	 * the handle in between. Does not apply to directories. True?
	 */
	if (fDirectory) {
		rc = VbglR0SfClose(&client_handle, &sf_g->map, params.Handle);
		if (RT_FAILURE(rc))
			LogFunc(("(%d): VbglR0SfClose failed rc=%Rrc\n",
				 fDirectory, rc));
	}

	sf_i->force_restat = 1;
	return 0;

 fail2:
	rc = VbglR0SfClose(&client_handle, &sf_g->map, params.Handle);
	if (RT_FAILURE(rc))
		LogFunc(("(%d): VbglR0SfClose failed rc=%Rrc\n", fDirectory,
			 rc));

 fail1:
	kfree(path);

 fail0:
	return err;
}

/**
 * Create a new regular file.
 *
 * @param parent        inode of the directory
 * @param dentry        directory cache entry
 * @param mode          file mode
 * @param excl          Possible O_EXCL...
 * @returns 0 on success, Linux error code otherwise
 */
#if LINUX_VERSION_CODE >= KERNEL_VERSION(3, 6, 0) || defined(DOXYGEN_RUNNING)
static int sf_create(struct inode *parent, struct dentry *dentry, umode_t mode,
		     bool excl)
#elif LINUX_VERSION_CODE >= KERNEL_VERSION(3, 3, 0)
static int sf_create(struct inode *parent, struct dentry *dentry, umode_t mode,
		     struct nameidata *nd)
#elif LINUX_VERSION_CODE >= KERNEL_VERSION(2, 6, 0)
static int sf_create(struct inode *parent, struct dentry *dentry, int mode,
		     struct nameidata *nd)
#else
static int sf_create(struct inode *parent, struct dentry *dentry, int mode)
#endif
{
	TRACE();
	return sf_create_aux(parent, dentry, mode, 0);
}

/**
 * Create a new directory.
 *
 * @param parent        inode of the directory
 * @param dentry        directory cache entry
 * @param mode          file mode
 * @returns 0 on success, Linux error code otherwise
 */
#if LINUX_VERSION_CODE >= KERNEL_VERSION(3, 3, 0)
static int sf_mkdir(struct inode *parent, struct dentry *dentry, umode_t mode)
#else
static int sf_mkdir(struct inode *parent, struct dentry *dentry, int mode)
#endif
{
	TRACE();
	return sf_create_aux(parent, dentry, mode, 1);
}

/**
 * Remove a regular file / directory.
 *
 * @param parent        inode of the directory
 * @param dentry        directory cache entry
 * @param fDirectory    true if directory, false otherwise
 * @returns 0 on success, Linux error code otherwise
 */
static int sf_unlink_aux(struct inode *parent, struct dentry *dentry,
			 int fDirectory)
{
	int rc, err;
	struct sf_glob_info *sf_g = GET_GLOB_INFO(parent->i_sb);
	struct sf_inode_info *sf_i = GET_INODE_INFO(parent);
	SHFLSTRING *path;
	uint32_t fFlags;

	TRACE();
	BUG_ON(!sf_g);

	err = sf_path_from_dentry(__func__, sf_g, sf_i, dentry, &path);
	if (err)
		goto fail0;

	fFlags = fDirectory ? SHFL_REMOVE_DIR : SHFL_REMOVE_FILE;
	if (dentry->d_inode && ((dentry->d_inode->i_mode & S_IFLNK) == S_IFLNK))
		fFlags |= SHFL_REMOVE_SYMLINK;
	rc = VbglR0SfRemove(&client_handle, &sf_g->map, path, fFlags);
	if (RT_FAILURE(rc)) {
		LogFunc(("(%d): VbglR0SfRemove(%s) failed rc=%Rrc\n",
			 fDirectory, path->String.utf8, rc));
		err = -RTErrConvertToErrno(rc);
		goto fail1;
	}

	/* directory access/change time changed */
	sf_i->force_restat = 1;
	/* directory content changed */
	sf_i->force_reread = 1;

	err = 0;

 fail1:
	kfree(path);

 fail0:
	return err;
}

/**
 * Remove a regular file.
 *
 * @param parent        inode of the directory
 * @param dentry        directory cache entry
 * @returns 0 on success, Linux error code otherwise
 */
static int sf_unlink(struct inode *parent, struct dentry *dentry)
{
	TRACE();
	return sf_unlink_aux(parent, dentry, 0);
}

/**
 * Remove a directory.
 *
 * @param parent        inode of the directory
 * @param dentry        directory cache entry
 * @returns 0 on success, Linux error code otherwise
 */
static int sf_rmdir(struct inode *parent, struct dentry *dentry)
{
	TRACE();
	return sf_unlink_aux(parent, dentry, 1);
}

/**
 * Rename a regular file / directory.
 *
 * @param old_parent    inode of the old parent directory
 * @param old_dentry    old directory cache entry
 * @param new_parent    inode of the new parent directory
 * @param new_dentry    new directory cache entry
 * @param flags         flags
 * @returns 0 on success, Linux error code otherwise
 */
static int sf_rename(struct inode *old_parent, struct dentry *old_dentry,
		     struct inode *new_parent, struct dentry *new_dentry
#if LINUX_VERSION_CODE >= KERNEL_VERSION(4, 9, 0)
		     , unsigned flags
#endif
    )
{
	int err = 0, rc = VINF_SUCCESS;
	struct sf_glob_info *sf_g = GET_GLOB_INFO(old_parent->i_sb);

	TRACE();

#if LINUX_VERSION_CODE >= KERNEL_VERSION(4, 9, 0)
	if (flags) {
		LogFunc(("rename with flags=%x\n", flags));
		return -EINVAL;
	}
#endif

	if (sf_g != GET_GLOB_INFO(new_parent->i_sb)) {
		LogFunc(("rename with different roots\n"));
		err = -EINVAL;
	} else {
		struct sf_inode_info *sf_old_i = GET_INODE_INFO(old_parent);
		struct sf_inode_info *sf_new_i = GET_INODE_INFO(new_parent);
		/* As we save the relative path inside the inode structure, we need to change
		   this if the rename is successful. */
		struct sf_inode_info *sf_file_i =
		    GET_INODE_INFO(old_dentry->d_inode);
		SHFLSTRING *old_path;
		SHFLSTRING *new_path;

		BUG_ON(!sf_old_i);
		BUG_ON(!sf_new_i);
		BUG_ON(!sf_file_i);

		old_path = sf_file_i->path;
		err = sf_path_from_dentry(__func__, sf_g, sf_new_i,
					  new_dentry, &new_path);
		if (err)
			LogFunc(("failed to create new path\n"));
		else {
			int fDir =
			    ((old_dentry->d_inode->i_mode & S_IFDIR) != 0);

			rc = VbglR0SfRename(&client_handle, &sf_g->map,
					    old_path, new_path,
					    fDir ? 0 : SHFL_RENAME_FILE |
					    SHFL_RENAME_REPLACE_IF_EXISTS);
			if (RT_SUCCESS(rc)) {
				kfree(old_path);
				sf_new_i->force_restat = 1;
				sf_old_i->force_restat = 1;	/* XXX: needed? */
				/* Set the new relative path in the inode. */
				sf_file_i->path = new_path;
			} else {
				LogFunc(("VbglR0SfRename failed rc=%Rrc\n",
					 rc));
				err = -RTErrConvertToErrno(rc);
				kfree(new_path);
			}
		}
	}
	return err;
}

#if LINUX_VERSION_CODE >= KERNEL_VERSION(2, 6, 0)
static int sf_symlink(struct inode *parent, struct dentry *dentry,
		      const char *symname)
{
	int err;
	int rc;
	struct sf_inode_info *sf_i;
	struct sf_glob_info *sf_g;
	SHFLSTRING *path, *ssymname;
	SHFLFSOBJINFO info;
	int symname_len = strlen(symname) + 1;

	TRACE();
	sf_g = GET_GLOB_INFO(parent->i_sb);
	sf_i = GET_INODE_INFO(parent);

	BUG_ON(!sf_g);
	BUG_ON(!sf_i);

	err = sf_path_from_dentry(__func__, sf_g, sf_i, dentry, &path);
	if (err)
		goto fail0;

	ssymname =
	    kmalloc(offsetof(SHFLSTRING, String.utf8) + symname_len,
		    GFP_KERNEL);
	if (!ssymname) {
		LogRelFunc(("kmalloc failed, caller=sf_symlink\n"));
		err = -ENOMEM;
		goto fail1;
	}

	ssymname->u16Length = symname_len - 1;
	ssymname->u16Size = symname_len;
	memcpy(ssymname->String.utf8, symname, symname_len);

	rc = VbglR0SfSymlink(&client_handle, &sf_g->map, path, ssymname, &info);
	kfree(ssymname);

	if (RT_FAILURE(rc)) {
		if (rc == VERR_WRITE_PROTECT) {
			err = -EROFS;
			goto fail1;
		}
		LogFunc(("VbglR0SfSymlink(%s) failed rc=%Rrc\n",
			 sf_i->path->String.utf8, rc));
		err = -EPROTO;
		goto fail1;
	}

	err = sf_instantiate(parent, dentry, path, &info, SHFL_HANDLE_NIL);
	if (err) {
		LogFunc(("could not instantiate dentry for %s err=%d\n",
			 sf_i->path->String.utf8, err));
		goto fail1;
	}

	sf_i->force_restat = 1;
	return 0;

 fail1:
	kfree(path);
 fail0:
	return err;
}
#endif /* LINUX_VERSION_CODE >= 2.6.0 */

struct inode_operations sf_dir_iops = {
	.lookup = sf_lookup,
	.create = sf_create,
	.mkdir = sf_mkdir,
	.rmdir = sf_rmdir,
	.unlink = sf_unlink,
	.rename = sf_rename,
#if LINUX_VERSION_CODE < KERNEL_VERSION(2, 6, 0)
	.revalidate = sf_inode_revalidate
#else
	.getattr = sf_getattr,
	.setattr = sf_setattr,
	.symlink = sf_symlink
#endif
};