Commit 0e3f1ad8 authored by Linus Torvalds's avatar Linus Torvalds

Remove VirtualBox guest shared folders filesystem

This went into staging in rc7.  It turns out that was a mistake, and
apparently it wasn't even supposed to go there at all, but be introduced
as a regular filesystem.

We don't try to sneak in whole new filesystems this late in the rc, just
delete the whole thing, and it can be re-introduced as a proper patch
with proper acks from actual filesystem people instead of some odd
late-rc staging back-door.

Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 8c5bd25b
......@@ -17338,12 +17338,6 @@ F: include/linux/vbox_utils.h
F: include/uapi/linux/vbox*.h
F: drivers/virt/vboxguest/
VIRTUAL BOX SHARED FOLDER VFS DRIVER:
M: Hans de Goede <hdegoede@redhat.com>
L: linux-fsdevel@vger.kernel.org
S: Maintained
F: drivers/staging/vboxsf/*
VIRTUAL SERIO DEVICE DRIVER
M: Stephen Chandler Paul <thatslyude@gmail.com>
S: Maintained
......
......@@ -125,6 +125,4 @@ source "drivers/staging/exfat/Kconfig"
source "drivers/staging/qlge/Kconfig"
source "drivers/staging/vboxsf/Kconfig"
endif # STAGING
......@@ -53,4 +53,3 @@ obj-$(CONFIG_UWB) += uwb/
obj-$(CONFIG_USB_WUSB) += wusbcore/
obj-$(CONFIG_EXFAT_FS) += exfat/
obj-$(CONFIG_QLGE) += qlge/
obj-$(CONFIG_VBOXSF_FS) += vboxsf/
config VBOXSF_FS
tristate "VirtualBox guest shared folder (vboxsf) support"
depends on X86 && VBOXGUEST
select NLS
help
VirtualBox hosts can share folders with guests, this driver
implements the Linux-guest side of this allowing folders exported
by the host to be mounted under Linux.
If you want to use shared folders in VirtualBox guests, answer Y or M.
# SPDX-License-Identifier: MIT
obj-$(CONFIG_VBOXSF_FS) += vboxsf.o
vboxsf-y := dir.o file.o utils.o vboxsf_wrappers.o super.o
TODO:
- Find a file-system developer to review this and give their Reviewed-By
- Address any items coming up during review
- Move to fs/vboxfs
Please send any patches to Greg Kroah-Hartman <gregkh@linuxfoundation.org>
and Hans de Goede <hdegoede@redhat.com>
This diff is collapsed.
// SPDX-License-Identifier: MIT
/*
* VirtualBox Guest Shared Folders support: Regular file inode and file ops.
*
* Copyright (C) 2006-2018 Oracle Corporation
*/
#include <linux/mm.h>
#include <linux/page-flags.h>
#include <linux/pagemap.h>
#include <linux/highmem.h>
#include <linux/sizes.h>
#include "vfsmod.h"
struct vboxsf_handle {
u64 handle;
u32 root;
u32 access_flags;
struct kref refcount;
struct list_head head;
};
static int vboxsf_file_open(struct inode *inode, struct file *file)
{
struct vboxsf_inode *sf_i = VBOXSF_I(inode);
struct shfl_createparms params = {};
struct vboxsf_handle *sf_handle;
u32 access_flags = 0;
int err;
sf_handle = kmalloc(sizeof(*sf_handle), GFP_KERNEL);
if (!sf_handle)
return -ENOMEM;
/*
* We check the value of params.handle afterwards to find out if
* the call succeeded or failed, as the API does not seem to cleanly
* distinguish error and informational messages.
*
* Furthermore, we must set params.handle to SHFL_HANDLE_NIL to
* make the shared folders host service use our mode parameter.
*/
params.handle = SHFL_HANDLE_NIL;
if (file->f_flags & O_CREAT) {
params.create_flags |= SHFL_CF_ACT_CREATE_IF_NEW;
/*
* We ignore O_EXCL, as the Linux kernel seems to call create
* beforehand itself, so O_EXCL should always fail.
*/
if (file->f_flags & O_TRUNC)
params.create_flags |= SHFL_CF_ACT_OVERWRITE_IF_EXISTS;
else
params.create_flags |= SHFL_CF_ACT_OPEN_IF_EXISTS;
} else {
params.create_flags |= SHFL_CF_ACT_FAIL_IF_NEW;
if (file->f_flags & O_TRUNC)
params.create_flags |= SHFL_CF_ACT_OVERWRITE_IF_EXISTS;
}
switch (file->f_flags & O_ACCMODE) {
case O_RDONLY:
access_flags |= SHFL_CF_ACCESS_READ;
break;
case O_WRONLY:
access_flags |= SHFL_CF_ACCESS_WRITE;
break;
case O_RDWR:
access_flags |= SHFL_CF_ACCESS_READWRITE;
break;
default:
WARN_ON(1);
}
if (file->f_flags & O_APPEND)
access_flags |= SHFL_CF_ACCESS_APPEND;
params.create_flags |= access_flags;
params.info.attr.mode = inode->i_mode;
err = vboxsf_create_at_dentry(file_dentry(file), &params);
if (err == 0 && params.handle == SHFL_HANDLE_NIL)
err = (params.result == SHFL_FILE_EXISTS) ? -EEXIST : -ENOENT;
if (err) {
kfree(sf_handle);
return err;
}
/* the host may have given us different attr then requested */
sf_i->force_restat = 1;
/* init our handle struct and add it to the inode's handles list */
sf_handle->handle = params.handle;
sf_handle->root = VBOXSF_SBI(inode->i_sb)->root;
sf_handle->access_flags = access_flags;
kref_init(&sf_handle->refcount);
mutex_lock(&sf_i->handle_list_mutex);
list_add(&sf_handle->head, &sf_i->handle_list);
mutex_unlock(&sf_i->handle_list_mutex);
file->private_data = sf_handle;
return 0;
}
static void vboxsf_handle_release(struct kref *refcount)
{
struct vboxsf_handle *sf_handle =
container_of(refcount, struct vboxsf_handle, refcount);
vboxsf_close(sf_handle->root, sf_handle->handle);
kfree(sf_handle);
}
static int vboxsf_file_release(struct inode *inode, struct file *file)
{
struct vboxsf_inode *sf_i = VBOXSF_I(inode);
struct vboxsf_handle *sf_handle = file->private_data;
/*
* When a file is closed on our (the guest) side, we want any subsequent
* accesses done on the host side to see all changes done from our side.
*/
filemap_write_and_wait(inode->i_mapping);
mutex_lock(&sf_i->handle_list_mutex);
list_del(&sf_handle->head);
mutex_unlock(&sf_i->handle_list_mutex);
kref_put(&sf_handle->refcount, vboxsf_handle_release);
return 0;
}
/*
* Write back dirty pages now, because there may not be any suitable
* open files later
*/
static void vboxsf_vma_close(struct vm_area_struct *vma)
{
filemap_write_and_wait(vma->vm_file->f_mapping);
}
static const struct vm_operations_struct vboxsf_file_vm_ops = {
.close = vboxsf_vma_close,
.fault = filemap_fault,
.map_pages = filemap_map_pages,
};
static int vboxsf_file_mmap(struct file *file, struct vm_area_struct *vma)
{
int err;
err = generic_file_mmap(file, vma);
if (!err)
vma->vm_ops = &vboxsf_file_vm_ops;
return err;
}
/*
* Note that since we are accessing files on the host's filesystem, files
* may always be changed underneath us by the host!
*
* The vboxsf API between the guest and the host does not offer any functions
* to deal with this. There is no inode-generation to check for changes, no
* events / callback on changes and no way to lock files.
*
* To avoid returning stale data when a file gets *opened* on our (the guest)
* side, we do a "stat" on the host side, then compare the mtime with the
* last known mtime and invalidate the page-cache if they differ.
* This is done from vboxsf_inode_revalidate().
*
* When reads are done through the read_iter fop, it is possible to do
* further cache revalidation then, there are 3 options to deal with this:
*
* 1) Rely solely on the revalidation done at open time
* 2) Do another "stat" and compare mtime again. Unfortunately the vboxsf
* host API does not allow stat on handles, so we would need to use
* file->f_path.dentry and the stat will then fail if the file was unlinked
* or renamed (and there is no thing like NFS' silly-rename). So we get:
* 2a) "stat" and compare mtime, on stat failure invalidate the cache
* 2b) "stat" and compare mtime, on stat failure do nothing
* 3) Simply always call invalidate_inode_pages2_range on the range of the read
*
* Currently we are keeping things KISS and using option 1. this allows
* directly using generic_file_read_iter without wrapping it.
*
* This means that only data written on the host side before open() on
* the guest side is guaranteed to be seen by the guest. If necessary
* we may provide other read-cache strategies in the future and make this
* configurable through a mount option.
*/
const struct file_operations vboxsf_reg_fops = {
.llseek = generic_file_llseek,
.read_iter = generic_file_read_iter,
.write_iter = generic_file_write_iter,
.mmap = vboxsf_file_mmap,
.open = vboxsf_file_open,
.release = vboxsf_file_release,
.fsync = noop_fsync,
.splice_read = generic_file_splice_read,
};
const struct inode_operations vboxsf_reg_iops = {
.getattr = vboxsf_getattr,
.setattr = vboxsf_setattr
};
static int vboxsf_readpage(struct file *file, struct page *page)
{
struct vboxsf_handle *sf_handle = file->private_data;
loff_t off = page_offset(page);
u32 nread = PAGE_SIZE;
u8 *buf;
int err;
buf = kmap(page);
err = vboxsf_read(sf_handle->root, sf_handle->handle, off, &nread, buf);
if (err == 0) {
memset(&buf[nread], 0, PAGE_SIZE - nread);
flush_dcache_page(page);
SetPageUptodate(page);
} else {
SetPageError(page);
}
kunmap(page);
unlock_page(page);
return err;
}
static struct vboxsf_handle *vboxsf_get_write_handle(struct vboxsf_inode *sf_i)
{
struct vboxsf_handle *h, *sf_handle = NULL;
mutex_lock(&sf_i->handle_list_mutex);
list_for_each_entry(h, &sf_i->handle_list, head) {
if (h->access_flags == SHFL_CF_ACCESS_WRITE ||
h->access_flags == SHFL_CF_ACCESS_READWRITE) {
kref_get(&h->refcount);
sf_handle = h;
break;
}
}
mutex_unlock(&sf_i->handle_list_mutex);
return sf_handle;
}
static int vboxsf_writepage(struct page *page, struct writeback_control *wbc)
{
struct inode *inode = page->mapping->host;
struct vboxsf_inode *sf_i = VBOXSF_I(inode);
struct vboxsf_handle *sf_handle;
loff_t off = page_offset(page);
loff_t size = i_size_read(inode);
u32 nwrite = PAGE_SIZE;
u8 *buf;
int err;
if (off + PAGE_SIZE > size)
nwrite = size & ~PAGE_MASK;
sf_handle = vboxsf_get_write_handle(sf_i);
if (!sf_handle)
return -EBADF;
buf = kmap(page);
err = vboxsf_write(sf_handle->root, sf_handle->handle,
off, &nwrite, buf);
kunmap(page);
kref_put(&sf_handle->refcount, vboxsf_handle_release);
if (err == 0) {
ClearPageError(page);
/* mtime changed */
sf_i->force_restat = 1;
} else {
ClearPageUptodate(page);
}
unlock_page(page);
return err;
}
static int vboxsf_write_end(struct file *file, struct address_space *mapping,
loff_t pos, unsigned int len, unsigned int copied,
struct page *page, void *fsdata)
{
struct inode *inode = mapping->host;
struct vboxsf_handle *sf_handle = file->private_data;
unsigned int from = pos & ~PAGE_MASK;
u32 nwritten = len;
u8 *buf;
int err;
buf = kmap(page);
err = vboxsf_write(sf_handle->root, sf_handle->handle,
pos, &nwritten, buf + from);
kunmap(page);
if (err) {
nwritten = 0;
goto out;
}
/* mtime changed */
VBOXSF_I(inode)->force_restat = 1;
if (!PageUptodate(page) && nwritten == PAGE_SIZE)
SetPageUptodate(page);
pos += nwritten;
if (pos > inode->i_size)
i_size_write(inode, pos);
out:
unlock_page(page);
put_page(page);
return nwritten;
}
const struct address_space_operations vboxsf_reg_aops = {
.readpage = vboxsf_readpage,
.writepage = vboxsf_writepage,
.set_page_dirty = __set_page_dirty_nobuffers,
.write_begin = simple_write_begin,
.write_end = vboxsf_write_end,
};
static const char *vboxsf_get_link(struct dentry *dentry, struct inode *inode,
struct delayed_call *done)
{
struct vboxsf_sbi *sbi = VBOXSF_SBI(inode->i_sb);
struct shfl_string *path;
char *link;
int err;
if (!dentry)
return ERR_PTR(-ECHILD);
path = vboxsf_path_from_dentry(sbi, dentry);
if (IS_ERR(path))
return (char *)path;
link = kzalloc(PATH_MAX, GFP_KERNEL);
if (!link) {
__putname(path);
return ERR_PTR(-ENOMEM);
}
err = vboxsf_readlink(sbi->root, path, PATH_MAX, link);
__putname(path);
if (err) {
kfree(link);
return ERR_PTR(err);
}
set_delayed_call(done, kfree_link, link);
return link;
}
const struct inode_operations vboxsf_lnk_iops = {
.get_link = vboxsf_get_link
};
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/* SPDX-License-Identifier: MIT */
/*
* VirtualBox Guest Shared Folders support: module header.
*
* Copyright (C) 2006-2018 Oracle Corporation
*/
#ifndef VFSMOD_H
#define VFSMOD_H
#include <linux/backing-dev.h>
#include <linux/idr.h>
#include "shfl_hostintf.h"
#define DIR_BUFFER_SIZE SZ_16K
/* The cast is to prevent assignment of void * to pointers of arbitrary type */
#define VBOXSF_SBI(sb) ((struct vboxsf_sbi *)(sb)->s_fs_info)
#define VBOXSF_I(i) container_of(i, struct vboxsf_inode, vfs_inode)
struct vboxsf_options {
unsigned long ttl;
kuid_t uid;
kgid_t gid;
bool dmode_set;
bool fmode_set;
umode_t dmode;
umode_t fmode;
umode_t dmask;
umode_t fmask;
};
struct vboxsf_fs_context {
struct vboxsf_options o;
char *nls_name;
};
/* per-shared folder information */
struct vboxsf_sbi {
struct vboxsf_options o;
struct shfl_fsobjinfo root_info;
struct idr ino_idr;
spinlock_t ino_idr_lock; /* This protects ino_idr */
struct nls_table *nls;
u32 next_generation;
u32 root;
int bdi_id;
};
/* per-inode information */
struct vboxsf_inode {
/* some information was changed, update data on next revalidate */
int force_restat;
/* list of open handles for this inode + lock protecting it */
struct list_head handle_list;
/* This mutex protects handle_list accesses */
struct mutex handle_list_mutex;
/* The VFS inode struct */
struct inode vfs_inode;
};
struct vboxsf_dir_info {
struct list_head info_list;
};
struct vboxsf_dir_buf {
size_t entries;
size_t free;
size_t used;
void *buf;
struct list_head head;
};
/* globals */
extern const struct inode_operations vboxsf_dir_iops;
extern const struct inode_operations vboxsf_lnk_iops;
extern const struct inode_operations vboxsf_reg_iops;
extern const struct file_operations vboxsf_dir_fops;
extern const struct file_operations vboxsf_reg_fops;
extern const struct address_space_operations vboxsf_reg_aops;
extern const struct dentry_operations vboxsf_dentry_ops;
/* from utils.c */
struct inode *vboxsf_new_inode(struct super_block *sb);
void vboxsf_init_inode(struct vboxsf_sbi *sbi, struct inode *inode,
const struct shfl_fsobjinfo *info);
int vboxsf_create_at_dentry(struct dentry *dentry,
struct shfl_createparms *params);
int vboxsf_stat(struct vboxsf_sbi *sbi, struct shfl_string *path,
struct shfl_fsobjinfo *info);
int vboxsf_stat_dentry(struct dentry *dentry, struct shfl_fsobjinfo *info);
int vboxsf_inode_revalidate(struct dentry *dentry);
int vboxsf_getattr(const struct path *path, struct kstat *kstat,
u32 request_mask, unsigned int query_flags);
int vboxsf_setattr(struct dentry *dentry, struct iattr *iattr);
struct shfl_string *vboxsf_path_from_dentry(struct vboxsf_sbi *sbi,
struct dentry *dentry);
int vboxsf_nlscpy(struct vboxsf_sbi *sbi, char *name, size_t name_bound_len,
const unsigned char *utf8_name, size_t utf8_len);
struct vboxsf_dir_info *vboxsf_dir_info_alloc(void);
void vboxsf_dir_info_free(struct vboxsf_dir_info *p);
int vboxsf_dir_read_all(struct vboxsf_sbi *sbi, struct vboxsf_dir_info *sf_d,
u64 handle);
/* from vboxsf_wrappers.c */
int vboxsf_connect(void);
void vboxsf_disconnect(void);
int vboxsf_create(u32 root, struct shfl_string *parsed_path,
struct shfl_createparms *create_parms);
int vboxsf_close(u32 root, u64 handle);
int vboxsf_remove(u32 root, struct shfl_string *parsed_path, u32 flags);
int vboxsf_rename(u32 root, struct shfl_string *src_path,
struct shfl_string *dest_path, u32 flags);
int vboxsf_read(u32 root, u64 handle, u64 offset, u32 *buf_len, u8 *buf);
int vboxsf_write(u32 root, u64 handle, u64 offset, u32 *buf_len, u8 *buf);
int vboxsf_dirinfo(u32 root, u64 handle,
struct shfl_string *parsed_path, u32 flags, u32 index,
u32 *buf_len, struct shfl_dirinfo *buf, u32 *file_count);
int vboxsf_fsinfo(u32 root, u64 handle, u32 flags,
u32 *buf_len, void *buf);
int vboxsf_map_folder(struct shfl_string *folder_name, u32 *root);
int vboxsf_unmap_folder(u32 root);
int vboxsf_readlink(u32 root, struct shfl_string *parsed_path,
u32 buf_len, u8 *buf);
int vboxsf_symlink(u32 root, struct shfl_string *new_path,
struct shfl_string *old_path, struct shfl_fsobjinfo *buf);
int vboxsf_set_utf8(void);
int vboxsf_set_symlinks(void);
#endif
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