/**
* 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;
}
static int sf_remount_fs(struct super_block *sb, int *flags, char *data)
{
#if LINUX_VERSION_CODE >= KERNEL_VERSION(2, 4, 23)
struct sf_glob_info *sf_g;
struct vbsf_mount_info_new *info;
struct sf_inode_info *sf_i;
struct inode *iroot;
SHFLFSOBJINFO fsinfo;
int err;
printk(KERN_DEBUG "ENTER: sf_remount_fs\n");
sf_g = GET_GLOB_INFO(sb);
BUG_ON(!sf_g);
BUG_ON(data[0] != 0);
info = (struct vbsf_mount_info_new *)data;
BUG_ON( info->signature[0] != VBSF_MOUNT_SIGNATURE_BYTE_0
|| info->signature[1] != VBSF_MOUNT_SIGNATURE_BYTE_1
|| info->signature[2] != VBSF_MOUNT_SIGNATURE_BYTE_2);
sf_g->uid = info->uid;
sf_g->gid = info->gid;
sf_g->ttl = info->ttl;
sf_g->dmode = info->dmode;
sf_g->fmode = info->fmode;
sf_g->dmask = info->dmask;
sf_g->fmask = info->fmask;
iroot = ilookup(sb, 0);
if (!iroot)
{
printk(KERN_DEBUG "can't find root inode\n");
return -ENOSYS;
}
sf_i = GET_INODE_INFO(iroot);
err = sf_stat(__func__, sf_g, sf_i->path, &fsinfo, 0);
BUG_ON(err != 0);
sf_init_inode(sf_g, iroot, &fsinfo);
/*unlock_new_inode(iroot);*/
printk(KERN_DEBUG "LEAVE: sf_remount_fs\n");
return 0;
#else
return -ENOSYS;
#endif
}
static int sf_remount_fs(struct super_block *sb, int *flags, char *data)
{
#if LINUX_VERSION_CODE >= KERNEL_VERSION(2, 4, 23)
struct sf_glob_info *sf_g;
struct sf_inode_info *sf_i;
struct inode *iroot;
SHFLFSOBJINFO fsinfo;
int err;
sf_g = GET_GLOB_INFO(sb);
BUG_ON(!sf_g);
if (data && data[0] != 0)
{
struct vbsf_mount_info_new *info =
(struct vbsf_mount_info_new *)data;
if ( info->signature[0] == VBSF_MOUNT_SIGNATURE_BYTE_0
&& info->signature[1] == VBSF_MOUNT_SIGNATURE_BYTE_1
&& info->signature[2] == VBSF_MOUNT_SIGNATURE_BYTE_2)
{
sf_g->uid = info->uid;
sf_g->gid = info->gid;
sf_g->ttl = info->ttl;
sf_g->dmode = info->dmode;
sf_g->fmode = info->fmode;
sf_g->dmask = info->dmask;
sf_g->fmask = info->fmask;
}
}
iroot = ilookup(sb, 0);
if (!iroot)
return -ENOSYS;
sf_i = GET_INODE_INFO(iroot);
err = sf_stat(__func__, sf_g, sf_i->path, &fsinfo, 0);
BUG_ON(err != 0);
sf_init_inode(sf_g, iroot, &fsinfo);
/*unlock_new_inode(iroot);*/
return 0;
#else
return -ENOSYS;
#endif
}
/* this is called directly as iop on 2.4, indirectly as dop
[sf_dentry_revalidate] on 2.4/2.6, indirectly as iop through
[sf_getattr] on 2.6. the job is to find out whether dentry/inode is
still valid. the test is failed if [dentry] does not have an inode
or [sf_stat] is unsuccessful, otherwise we return success and
update inode attributes */
int sf_inode_revalidate(struct dentry *dentry)
{
int err;
struct sf_glob_info *sf_g;
struct sf_inode_info *sf_i;
SHFLFSOBJINFO info;
TRACE();
if (!dentry || !dentry->d_inode)
{
LogFunc(("no dentry(%p) or inode(%p)\n", dentry, dentry->d_inode));
return -EINVAL;
}
sf_g = GET_GLOB_INFO(dentry->d_inode->i_sb);
sf_i = GET_INODE_INFO(dentry->d_inode);
#if 0
printk("%s called by %p:%p\n",
sf_i->path->String.utf8,
__builtin_return_address (0),
__builtin_return_address (1));
#endif
BUG_ON(!sf_g);
BUG_ON(!sf_i);
if (!sf_i->force_restat)
{
if (jiffies - dentry->d_time < sf_g->ttl)
return 0;
}
err = sf_stat(__func__, sf_g, sf_i->path, &info, 1);
if (err)
return err;
dentry->d_time = jiffies;
sf_init_inode(sf_g, dentry->d_inode, &info);
return 0;
}
/**
* This is called (by sf_read_super_[24|26] when vfs mounts the fs and
* wants to read super_block.
*
* calls [sf_glob_alloc] to map the folder and allocate global
* information structure.
*
* initializes [sb], initializes root inode and dentry.
*
* should respect [flags]
*/
static int sf_read_super_aux(struct super_block *sb, void *data, int flags)
{
int err;
struct dentry *droot;
struct inode *iroot;
struct sf_inode_info *sf_i;
struct sf_glob_info *sf_g;
SHFLFSOBJINFO fsinfo;
struct vbsf_mount_info_new *info;
TRACE();
if (!data)
{
LogFunc(("no mount info specified\n"));
return -EINVAL;
}
info = data;
if (flags & MS_REMOUNT)
{
LogFunc(("remounting is not supported\n"));
return -ENOSYS;
}
err = sf_glob_alloc(info, &sf_g);
if (err)
goto fail0;
sf_i = kmalloc(sizeof (*sf_i), GFP_KERNEL);
if (!sf_i)
{
err = -ENOMEM;
LogRelFunc(("could not allocate memory for root inode info\n"));
goto fail1;
}
sf_i->handle = SHFL_HANDLE_NIL;
sf_i->path = kmalloc(sizeof(SHFLSTRING) + 1, GFP_KERNEL);
if (!sf_i->path)
{
err = -ENOMEM;
LogRelFunc(("could not allocate memory for root inode path\n"));
goto fail2;
}
sf_i->path->u16Length = 1;
sf_i->path->u16Size = 2;
sf_i->path->String.utf8[0] = '/';
sf_i->path->String.utf8[1] = 0;
err = sf_stat(__func__, sf_g, sf_i->path, &fsinfo, 0);
if (err)
{
LogFunc(("could not stat root of share\n"));
goto fail3;
}
sb->s_magic = 0xface;
sb->s_blocksize = 1024;
#if LINUX_VERSION_CODE >= KERNEL_VERSION(2, 4, 3)
/* Required for seek/sendfile.
*
* Must by less than or equal to INT64_MAX despite the fact that the
* declaration of this variable is unsigned long long. See determination
* of 'loff_t max' in fs/read_write.c / do_sendfile(). I don't know the
* correct limit but MAX_LFS_FILESIZE (8TB-1 on 32-bit boxes) takes the
* page cache into account and is the suggested limit. */
# if defined MAX_LFS_FILESIZE
sb->s_maxbytes = MAX_LFS_FILESIZE;
# else
sb->s_maxbytes = 0x7fffffffffffffffULL;
# endif
#endif
sb->s_op = &sf_super_ops;
#if LINUX_VERSION_CODE >= KERNEL_VERSION(2, 4, 25)
iroot = iget_locked(sb, 0);
#else
iroot = iget(sb, 0);
#endif
if (!iroot)
{
err = -ENOMEM; /* XXX */
LogFunc(("could not get root inode\n"));
goto fail3;
}
if (sf_init_backing_dev(sf_g))
{
err = -EINVAL;
LogFunc(("could not init bdi\n"));
#if LINUX_VERSION_CODE >= KERNEL_VERSION(2, 4, 25)
unlock_new_inode(iroot);
#endif
goto fail4;
}
sf_init_inode(sf_g, iroot, &fsinfo);
SET_INODE_INFO(iroot, sf_i);
#if LINUX_VERSION_CODE >= KERNEL_VERSION(2, 4, 25)
unlock_new_inode(iroot);
#endif
droot = d_alloc_root(iroot);
if (!droot)
{
err = -ENOMEM; /* XXX */
LogFunc(("d_alloc_root failed\n"));
goto fail5;
}
sb->s_root = droot;
SET_GLOB_INFO(sb, sf_g);
return 0;
fail5:
sf_done_backing_dev(sf_g);
fail4:
iput(iroot);
fail3:
kfree(sf_i->path);
fail2:
kfree(sf_i);
fail1:
sf_glob_free(sf_g);
fail0:
return err;
}
/**
* 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);
}