linux/fs/xfs/xfs_handle.c

// SPDX-License-Identifier: GPL-2.0
/*
 * Copyright (c) 2000-2005 Silicon Graphics, Inc.
 * Copyright (c) 2022-2024 Oracle.
 * All rights reserved.
 */
#include "xfs.h"
#include "xfs_fs.h"
#include "xfs_format.h"
#include "xfs_log_format.h"
#include "xfs_shared.h"
#include "xfs_trans_resv.h"
#include "xfs_mount.h"
#include "xfs_bmap_btree.h"
#include "xfs_inode.h"
#include "xfs_error.h"
#include "xfs_trace.h"
#include "xfs_trans.h"
#include "xfs_da_format.h"
#include "xfs_da_btree.h"
#include "xfs_attr.h"
#include "xfs_ioctl.h"
#include "xfs_parent.h"
#include "xfs_handle.h"
#include "xfs_health.h"
#include "xfs_icache.h"
#include "xfs_export.h"
#include "xfs_xattr.h"
#include "xfs_acl.h"

#include <linux/namei.h>

static inline size_t
xfs_filehandle_fid_len(void)
{ … }

static inline size_t
xfs_filehandle_init(
	struct xfs_mount	*mp,
	xfs_ino_t		ino,
	uint32_t		gen,
	struct xfs_handle	*handle)
{ … }

static inline size_t
xfs_fshandle_init(
	struct xfs_mount	*mp,
	struct xfs_handle	*handle)
{ … }

/*
 * xfs_find_handle maps from userspace xfs_fsop_handlereq structure to
 * a file or fs handle.
 *
 * XFS_IOC_PATH_TO_FSHANDLE
 *    returns fs handle for a mount point or path within that mount point
 * XFS_IOC_FD_TO_HANDLE
 *    returns full handle for a FD opened in user space
 * XFS_IOC_PATH_TO_HANDLE
 *    returns full handle for a path
 */
int
xfs_find_handle(
	unsigned int		cmd,
	xfs_fsop_handlereq_t	*hreq)
{ … }

/*
 * No need to do permission checks on the various pathname components
 * as the handle operations are privileged.
 */
STATIC int
xfs_handle_acceptable(
	void			*context,
	struct dentry		*dentry)
{ … }

/* Convert handle already copied to kernel space into a dentry. */
static struct dentry *
xfs_khandle_to_dentry(
	struct file		*file,
	struct xfs_handle	*handle)
{ … }

/* Convert handle already copied to kernel space into an xfs_inode. */
static struct xfs_inode *
xfs_khandle_to_inode(
	struct file		*file,
	struct xfs_handle	*handle)
{ … }

/*
 * Convert userspace handle data into a dentry.
 */
struct dentry *
xfs_handle_to_dentry(
	struct file		*parfilp,
	void __user		*uhandle,
	u32			hlen)
{ … }

STATIC struct dentry *
xfs_handlereq_to_dentry(
	struct file		*parfilp,
	xfs_fsop_handlereq_t	*hreq)
{ … }

int
xfs_open_by_handle(
	struct file		*parfilp,
	xfs_fsop_handlereq_t	*hreq)
{ … }

int
xfs_readlink_by_handle(
	struct file		*parfilp,
	xfs_fsop_handlereq_t	*hreq)
{ … }

/*
 * Format an attribute and copy it out to the user's buffer.
 * Take care to check values and protect against them changing later,
 * we may be reading them directly out of a user buffer.
 */
static void
xfs_ioc_attr_put_listent(
	struct xfs_attr_list_context *context,
	int			flags,
	unsigned char		*name,
	int			namelen,
	void			*value,
	int			valuelen)
{ … }

static unsigned int
xfs_attr_filter(
	u32			ioc_flags)
{ … }

static inline enum xfs_attr_update
xfs_xattr_flags(
	u32			ioc_flags,
	void			*value)
{ … }

int
xfs_ioc_attr_list(
	struct xfs_inode		*dp,
	void __user			*ubuf,
	size_t				bufsize,
	int				flags,
	struct xfs_attrlist_cursor __user *ucursor)
{ … }

int
xfs_attrlist_by_handle(
	struct file		*parfilp,
	struct xfs_fsop_attrlist_handlereq __user *p)
{ … }

static int
xfs_attrmulti_attr_get(
	struct inode		*inode,
	unsigned char		*name,
	unsigned char		__user *ubuf,
	uint32_t		*len,
	uint32_t		flags)
{ … }

static int
xfs_attrmulti_attr_set(
	struct inode		*inode,
	unsigned char		*name,
	const unsigned char	__user *ubuf,
	uint32_t		len,
	uint32_t		flags)
{ … }

int
xfs_ioc_attrmulti_one(
	struct file		*parfilp,
	struct inode		*inode,
	uint32_t		opcode,
	void __user		*uname,
	void __user		*value,
	uint32_t		*len,
	uint32_t		flags)
{ … }

int
xfs_attrmulti_by_handle(
	struct file		*parfilp,
	void			__user *arg)
{ … }

struct xfs_getparents_ctx { … };

static inline unsigned int
xfs_getparents_rec_sizeof(
	unsigned int		namelen)
{ … }

static void
xfs_getparents_put_listent(
	struct xfs_attr_list_context	*context,
	int				flags,
	unsigned char			*name,
	int				namelen,
	void				*value,
	int				valuelen)
{ … }

/* Expand the last record to fill the rest of the caller's buffer. */
static inline void
xfs_getparents_expand_lastrec(
	struct xfs_getparents_ctx	*gpx)
{ … }

/* Retrieve the parent pointers for a given inode. */
STATIC int
xfs_getparents(
	struct xfs_getparents_ctx	*gpx)
{ … }

/* Retrieve the parents of this file and pass them back to userspace. */
int
xfs_ioc_getparents(
	struct file			*file,
	struct xfs_getparents __user	*ureq)
{ … }

/* Retrieve the parents of this file handle and pass them back to userspace. */
int
xfs_ioc_getparents_by_handle(
	struct file			*file,
	struct xfs_getparents_by_handle __user	*ureq)
{ … }