#include <linux/idr.h>
#include <linux/fs_parser.h>
#include <linux/magic.h>
#include <linux/module.h>
#include <linux/nls.h>
#include <linux/statfs.h>
#include <linux/vbox_utils.h>
#include "vfsmod.h"
#define VBOXSF_SUPER_MAGIC 0x786f4256
static const unsigned char VBSF_MOUNT_SIGNATURE[4] __nonstring = "\000\377\376\375";
static int follow_symlinks;
module_param(follow_symlinks, int, 0444);
MODULE_PARM_DESC(follow_symlinks,
"Let host resolve symlinks rather than showing them");
static DEFINE_IDA(vboxsf_bdi_ida);
static DEFINE_MUTEX(vboxsf_setup_mutex);
static bool vboxsf_setup_done;
static struct super_operations vboxsf_super_ops;
static struct kmem_cache *vboxsf_inode_cachep;
static char * const vboxsf_default_nls = CONFIG_NLS_DEFAULT;
enum { opt_nls, opt_uid, opt_gid, opt_ttl, opt_dmode, opt_fmode,
opt_dmask, opt_fmask };
static const struct fs_parameter_spec vboxsf_fs_parameters[] = {
fsparam_string ("nls", opt_nls),
fsparam_uid ("uid", opt_uid),
fsparam_gid ("gid", opt_gid),
fsparam_u32 ("ttl", opt_ttl),
fsparam_u32oct ("dmode", opt_dmode),
fsparam_u32oct ("fmode", opt_fmode),
fsparam_u32oct ("dmask", opt_dmask),
fsparam_u32oct ("fmask", opt_fmask),
{}
};
static int vboxsf_parse_param(struct fs_context *fc, struct fs_parameter *param)
{
struct vboxsf_fs_context *ctx = fc->fs_private;
struct fs_parse_result result;
int opt;
opt = fs_parse(fc, vboxsf_fs_parameters, param, &result);
if (opt < 0)
return opt;
switch (opt) {
case opt_nls:
if (ctx->nls_name || fc->purpose != FS_CONTEXT_FOR_MOUNT) {
vbg_err("vboxsf: Cannot reconfigure nls option\n");
return -EINVAL;
}
ctx->nls_name = param->string;
param->string = NULL;
break;
case opt_uid:
ctx->o.uid = result.uid;
break;
case opt_gid:
ctx->o.gid = result.gid;
break;
case opt_ttl:
ctx->o.ttl = msecs_to_jiffies(result.uint_32);
break;
case opt_dmode:
if (result.uint_32 & ~0777)
return -EINVAL;
ctx->o.dmode = result.uint_32;
ctx->o.dmode_set = true;
break;
case opt_fmode:
if (result.uint_32 & ~0777)
return -EINVAL;
ctx->o.fmode = result.uint_32;
ctx->o.fmode_set = true;
break;
case opt_dmask:
if (result.uint_32 & ~07777)
return -EINVAL;
ctx->o.dmask = result.uint_32;
break;
case opt_fmask:
if (result.uint_32 & ~07777)
return -EINVAL;
ctx->o.fmask = result.uint_32;
break;
default:
return -EINVAL;
}
return 0;
}
static int vboxsf_fill_super(struct super_block *sb, struct fs_context *fc)
{
struct vboxsf_fs_context *ctx = fc->fs_private;
struct shfl_string *folder_name, root_path;
struct vboxsf_sbi *sbi;
struct dentry *droot;
struct inode *iroot;
char *nls_name;
size_t size;
int err;
if (!fc->source)
return -EINVAL;
sbi = kzalloc_obj(*sbi);
if (!sbi)
return -ENOMEM;
sbi->o = ctx->o;
idr_init(&sbi->ino_idr);
spin_lock_init(&sbi->ino_idr_lock);
sbi->next_generation = 1;
sbi->bdi_id = -1;
nls_name = ctx->nls_name ? ctx->nls_name : vboxsf_default_nls;
if (strcmp(nls_name, "utf8") != 0) {
if (nls_name == vboxsf_default_nls)
sbi->nls = load_nls_default();
else
sbi->nls = load_nls(nls_name);
if (!sbi->nls) {
vbg_err("vboxsf: Count not load '%s' nls\n", nls_name);
err = -EINVAL;
goto fail_destroy_idr;
}
}
sbi->bdi_id = ida_alloc(&vboxsf_bdi_ida, GFP_KERNEL);
if (sbi->bdi_id < 0) {
err = sbi->bdi_id;
goto fail_free;
}
err = super_setup_bdi_name(sb, "vboxsf-%d", sbi->bdi_id);
if (err)
goto fail_free;
sb->s_bdi->ra_pages = 0;
sb->s_bdi->io_pages = 0;
size = strlen(fc->source) + 1;
folder_name = kmalloc(SHFLSTRING_HEADER_SIZE + size, GFP_KERNEL);
if (!folder_name) {
err = -ENOMEM;
goto fail_free;
}
folder_name->size = size;
folder_name->length = size - 1;
strscpy(folder_name->string.utf8, fc->source, size);
err = vboxsf_map_folder(folder_name, &sbi->root);
kfree(folder_name);
if (err) {
vbg_err("vboxsf: Host rejected mount of '%s' with error %d\n",
fc->source, err);
goto fail_free;
}
root_path.length = 1;
root_path.size = 2;
root_path.string.utf8[0] = '/';
root_path.string.utf8[1] = 0;
err = vboxsf_stat(sbi, &root_path, &sbi->root_info);
if (err)
goto fail_unmap;
sb->s_magic = VBOXSF_SUPER_MAGIC;
sb->s_blocksize = 1024;
sb->s_maxbytes = MAX_LFS_FILESIZE;
sb->s_op = &vboxsf_super_ops;
set_default_d_op(sb, &vboxsf_dentry_ops);
iroot = iget_locked(sb, 0);
if (!iroot) {
err = -ENOMEM;
goto fail_unmap;
}
vboxsf_init_inode(sbi, iroot, &sbi->root_info, false);
unlock_new_inode(iroot);
droot = d_make_root(iroot);
if (!droot) {
err = -ENOMEM;
goto fail_unmap;
}
sb->s_root = droot;
sb->s_fs_info = sbi;
return 0;
fail_unmap:
vboxsf_unmap_folder(sbi->root);
fail_free:
if (sbi->bdi_id >= 0)
ida_free(&vboxsf_bdi_ida, sbi->bdi_id);
if (sbi->nls)
unload_nls(sbi->nls);
fail_destroy_idr:
idr_destroy(&sbi->ino_idr);
kfree(sbi);
return err;
}
static void vboxsf_inode_init_once(void *data)
{
struct vboxsf_inode *sf_i = data;
mutex_init(&sf_i->handle_list_mutex);
inode_init_once(&sf_i->vfs_inode);
}
static struct inode *vboxsf_alloc_inode(struct super_block *sb)
{
struct vboxsf_inode *sf_i;
sf_i = alloc_inode_sb(sb, vboxsf_inode_cachep, GFP_NOFS);
if (!sf_i)
return NULL;
sf_i->force_restat = 0;
INIT_LIST_HEAD(&sf_i->handle_list);
return &sf_i->vfs_inode;
}
static void vboxsf_free_inode(struct inode *inode)
{
struct vboxsf_sbi *sbi = VBOXSF_SBI(inode->i_sb);
unsigned long flags;
spin_lock_irqsave(&sbi->ino_idr_lock, flags);
idr_remove(&sbi->ino_idr, inode->i_ino);
spin_unlock_irqrestore(&sbi->ino_idr_lock, flags);
kmem_cache_free(vboxsf_inode_cachep, VBOXSF_I(inode));
}
static void vboxsf_put_super(struct super_block *sb)
{
struct vboxsf_sbi *sbi = VBOXSF_SBI(sb);
vboxsf_unmap_folder(sbi->root);
if (sbi->bdi_id >= 0)
ida_free(&vboxsf_bdi_ida, sbi->bdi_id);
if (sbi->nls)
unload_nls(sbi->nls);
rcu_barrier();
idr_destroy(&sbi->ino_idr);
kfree(sbi);
}
static int vboxsf_statfs(struct dentry *dentry, struct kstatfs *stat)
{
struct super_block *sb = dentry->d_sb;
struct shfl_volinfo shfl_volinfo;
struct vboxsf_sbi *sbi;
u32 buf_len;
int err;
sbi = VBOXSF_SBI(sb);
buf_len = sizeof(shfl_volinfo);
err = vboxsf_fsinfo(sbi->root, 0, SHFL_INFO_GET | SHFL_INFO_VOLUME,
&buf_len, &shfl_volinfo);
if (err)
return err;
stat->f_type = VBOXSF_SUPER_MAGIC;
stat->f_bsize = shfl_volinfo.bytes_per_allocation_unit;
do_div(shfl_volinfo.total_allocation_bytes,
shfl_volinfo.bytes_per_allocation_unit);
stat->f_blocks = shfl_volinfo.total_allocation_bytes;
do_div(shfl_volinfo.available_allocation_bytes,
shfl_volinfo.bytes_per_allocation_unit);
stat->f_bfree = shfl_volinfo.available_allocation_bytes;
stat->f_bavail = shfl_volinfo.available_allocation_bytes;
stat->f_files = 1000;
stat->f_ffree = 1000000;
stat->f_fsid.val[0] = 0;
stat->f_fsid.val[1] = 0;
stat->f_namelen = 255;
return 0;
}
static struct super_operations vboxsf_super_ops = {
.alloc_inode = vboxsf_alloc_inode,
.free_inode = vboxsf_free_inode,
.put_super = vboxsf_put_super,
.statfs = vboxsf_statfs,
};
static int vboxsf_setup(void)
{
int err;
mutex_lock(&vboxsf_setup_mutex);
if (vboxsf_setup_done)
goto success;
vboxsf_inode_cachep =
kmem_cache_create("vboxsf_inode_cache",
sizeof(struct vboxsf_inode), 0,
SLAB_RECLAIM_ACCOUNT | SLAB_ACCOUNT,
vboxsf_inode_init_once);
if (!vboxsf_inode_cachep) {
err = -ENOMEM;
goto fail_nomem;
}
err = vboxsf_connect();
if (err) {
vbg_err("vboxsf: err %d connecting to guest PCI-device\n", err);
vbg_err("vboxsf: make sure you are inside a VirtualBox VM\n");
vbg_err("vboxsf: and check dmesg for vboxguest errors\n");
goto fail_free_cache;
}
err = vboxsf_set_utf8();
if (err) {
vbg_err("vboxsf_setutf8 error %d\n", err);
goto fail_disconnect;
}
if (!follow_symlinks) {
err = vboxsf_set_symlinks();
if (err)
vbg_warn("vboxsf: Unable to show symlinks: %d\n", err);
}
vboxsf_setup_done = true;
success:
mutex_unlock(&vboxsf_setup_mutex);
return 0;
fail_disconnect:
vboxsf_disconnect();
fail_free_cache:
kmem_cache_destroy(vboxsf_inode_cachep);
fail_nomem:
mutex_unlock(&vboxsf_setup_mutex);
return err;
}
static int vboxsf_parse_monolithic(struct fs_context *fc, void *data)
{
if (data && !memcmp(data, VBSF_MOUNT_SIGNATURE, 4)) {
vbg_err("vboxsf: Old binary mount data not supported, remove obsolete mount.vboxsf and/or update your VBoxService.\n");
return -EINVAL;
}
return generic_parse_monolithic(fc, data);
}
static int vboxsf_get_tree(struct fs_context *fc)
{
int err;
err = vboxsf_setup();
if (err)
return err;
return get_tree_nodev(fc, vboxsf_fill_super);
}
static int vboxsf_reconfigure(struct fs_context *fc)
{
struct vboxsf_sbi *sbi = VBOXSF_SBI(fc->root->d_sb);
struct vboxsf_fs_context *ctx = fc->fs_private;
struct inode *iroot = fc->root->d_sb->s_root->d_inode;
sbi->o = ctx->o;
vboxsf_init_inode(sbi, iroot, &sbi->root_info, true);
return 0;
}
static void vboxsf_free_fc(struct fs_context *fc)
{
struct vboxsf_fs_context *ctx = fc->fs_private;
kfree(ctx->nls_name);
kfree(ctx);
}
static const struct fs_context_operations vboxsf_context_ops = {
.free = vboxsf_free_fc,
.parse_param = vboxsf_parse_param,
.parse_monolithic = vboxsf_parse_monolithic,
.get_tree = vboxsf_get_tree,
.reconfigure = vboxsf_reconfigure,
};
static int vboxsf_init_fs_context(struct fs_context *fc)
{
struct vboxsf_fs_context *ctx;
ctx = kzalloc_obj(*ctx);
if (!ctx)
return -ENOMEM;
current_uid_gid(&ctx->o.uid, &ctx->o.gid);
fc->fs_private = ctx;
fc->ops = &vboxsf_context_ops;
return 0;
}
static struct file_system_type vboxsf_fs_type = {
.owner = THIS_MODULE,
.name = "vboxsf",
.init_fs_context = vboxsf_init_fs_context,
.kill_sb = kill_anon_super
};
static int __init vboxsf_init(void)
{
return register_filesystem(&vboxsf_fs_type);
}
static void __exit vboxsf_fini(void)
{
unregister_filesystem(&vboxsf_fs_type);
mutex_lock(&vboxsf_setup_mutex);
if (vboxsf_setup_done) {
vboxsf_disconnect();
rcu_barrier();
kmem_cache_destroy(vboxsf_inode_cachep);
}
mutex_unlock(&vboxsf_setup_mutex);
}
module_init(vboxsf_init);
module_exit(vboxsf_fini);
MODULE_DESCRIPTION("Oracle VM VirtualBox Module for Host File System Access");
MODULE_AUTHOR("Oracle Corporation");
MODULE_LICENSE("GPL v2");
MODULE_ALIAS_FS("vboxsf");
