dir.c

linux下的用户文件系统fuse-2.5.2

}
#else
static int fuse_readlink(struct dentry *dentry, char __user *buffer,
			 int buflen)
{
	int ret;
	char *link;

	link = read_link(dentry);
	ret = vfs_readlink(dentry, buffer, buflen, link);
	free_link(link);
	return ret;
}

static int fuse_follow_link(struct dentry *dentry, struct nameidata *nd)
{
	int ret;
	char *link;

	link = read_link(dentry);
	ret = vfs_follow_link(nd, link);
	free_link(link);
	return ret;
}
#endif

static int fuse_dir_open(struct inode *inode, struct file *file)
{
	return fuse_open_common(inode, file, 1);
}

static int fuse_dir_release(struct inode *inode, struct file *file)
{
	return fuse_release_common(inode, file, 1);
}

static int fuse_dir_fsync(struct file *file, struct dentry *de, int datasync)
{
	/* nfsd can call this with no file */
	return file ? fuse_fsync_common(file, de, datasync, 1) : 0;
}

static void iattr_to_fattr(struct iattr *iattr, struct fuse_setattr_in *arg)
{
	unsigned ivalid = iattr->ia_valid;

	if (ivalid & ATTR_MODE)
		arg->valid |= FATTR_MODE,   arg->mode = iattr->ia_mode;
	if (ivalid & ATTR_UID)
		arg->valid |= FATTR_UID,    arg->uid = iattr->ia_uid;
	if (ivalid & ATTR_GID)
		arg->valid |= FATTR_GID,    arg->gid = iattr->ia_gid;
	if (ivalid & ATTR_SIZE)
		arg->valid |= FATTR_SIZE,   arg->size = iattr->ia_size;
	/* You can only _set_ these together (they may change by themselves) */
	if ((ivalid & (ATTR_ATIME | ATTR_MTIME)) == (ATTR_ATIME | ATTR_MTIME)) {
		arg->valid |= FATTR_ATIME | FATTR_MTIME;
#ifdef KERNEL_2_6
		arg->atime = iattr->ia_atime.tv_sec;
		arg->mtime = iattr->ia_mtime.tv_sec;
#else
		arg->atime = iattr->ia_atime;
		arg->mtime = iattr->ia_mtime;
#endif
	}
#ifdef ATTR_FILE
	if (ivalid & ATTR_FILE) {
		struct fuse_file *ff = iattr->ia_file->private_data;
		arg->valid |= FATTR_FH;
		arg->fh = ff->fh;
	}
#endif
}

/*
 * Set attributes, and at the same time refresh them.
 *
 * Truncation is slightly complicated, because the 'truncate' request
 * may fail, in which case we don't want to touch the mapping.
 * vmtruncate() doesn't allow for this case.  So do the rlimit
 * checking by hand and call vmtruncate() only after the file has
 * actually been truncated.
 */
static int fuse_setattr(struct dentry *entry, struct iattr *attr)
{
	struct inode *inode = entry->d_inode;
	struct fuse_conn *fc = get_fuse_conn(inode);
	struct fuse_inode *fi = get_fuse_inode(inode);
	struct fuse_req *req;
	struct fuse_setattr_in inarg;
	struct fuse_attr_out outarg;
	int err;
	int is_truncate = 0;

	if (fc->flags & FUSE_DEFAULT_PERMISSIONS) {
		err = inode_change_ok(inode, attr);
		if (err)
			return err;
	}

	if (attr->ia_valid & ATTR_SIZE) {
		unsigned long limit;
		is_truncate = 1;
#ifdef KERNEL_2_6_10_PLUS
		limit = current->signal->rlim[RLIMIT_FSIZE].rlim_cur;
#else
		limit = current->rlim[RLIMIT_FSIZE].rlim_cur;
#endif
		if (limit != RLIM_INFINITY && attr->ia_size > (loff_t) limit) {
			send_sig(SIGXFSZ, current, 0);
			return -EFBIG;
		}
	}

	req = fuse_get_request(fc);
	if (!req)
		return -EINTR;

	memset(&inarg, 0, sizeof(inarg));
	iattr_to_fattr(attr, &inarg);
	req->in.h.opcode = FUSE_SETATTR;
	req->in.h.nodeid = get_node_id(inode);
	req->inode = inode;
	req->in.numargs = 1;
	req->in.args[0].size = sizeof(inarg);
	req->in.args[0].value = &inarg;
	req->out.numargs = 1;
	req->out.args[0].size = sizeof(outarg);
	req->out.args[0].value = &outarg;
	request_send(fc, req);
	err = req->out.h.error;
	fuse_put_request(fc, req);
	if (!err) {
		if ((inode->i_mode ^ outarg.attr.mode) & S_IFMT) {
#ifndef KERNEL_2_6_12_PLUS
			if (get_node_id(inode) != FUSE_ROOT_ID)
				make_bad_inode(inode);
#else
			make_bad_inode(inode);
#endif
			err = -EIO;
		} else {
			if (is_truncate) {
				loff_t origsize = i_size_read(inode);
				i_size_write(inode, outarg.attr.size);
				if (origsize > outarg.attr.size)
					vmtruncate(inode, outarg.attr.size);
			}
			fuse_change_attributes(inode, &outarg.attr);
			fi->i_time = time_to_jiffies(outarg.attr_valid,
						     outarg.attr_valid_nsec);
		}
	} else if (err == -EINTR)
		fuse_invalidate_attr(inode);

	return err;
}

#ifdef KERNEL_2_6
static int fuse_getattr(struct vfsmount *mnt, struct dentry *entry,
			struct kstat *stat)
{
	struct inode *inode = entry->d_inode;
	int err = fuse_revalidate(entry);
	if (!err)
		generic_fillattr(inode, stat);

	return err;
}
#else /* KERNEL_2_6 */
static struct dentry *fuse_lookup_2_4(struct inode *dir, struct dentry *entry)
{
	return fuse_lookup(dir, entry, NULL);
}

static int fuse_mknod_2_4(struct inode *dir, struct dentry *entry, int mode,
			  int rdev)
{
	return fuse_mknod(dir, entry, mode, rdev);
}

static int fuse_create_2_4(struct inode *dir, struct dentry *entry, int mode)
{
	return fuse_create(dir, entry, mode, NULL);
}

static int fuse_permission_2_4(struct inode *inode, int mask)
{
	return fuse_permission(inode, mask, NULL);
}
#endif /* KERNEL_2_6 */

#ifdef HAVE_KERNEL_XATTR
#ifdef KERNEL_2_6
static int fuse_setxattr(struct dentry *entry, const char *name,
			 const void *value, size_t size, int flags)
#else
static int fuse_setxattr(struct dentry *entry, const char *name,
			 void *value, size_t size, int flags)
#endif
{
	struct inode *inode = entry->d_inode;
	struct fuse_conn *fc = get_fuse_conn(inode);
	struct fuse_req *req;
	struct fuse_setxattr_in inarg;
	int err;

	if (fc->no_setxattr)
		return -EOPNOTSUPP;

	req = fuse_get_request(fc);
	if (!req)
		return -EINTR;

	memset(&inarg, 0, sizeof(inarg));
	inarg.size = size;
	inarg.flags = flags;
	req->in.h.opcode = FUSE_SETXATTR;
	req->in.h.nodeid = get_node_id(inode);
	req->inode = inode;
	req->in.numargs = 3;
	req->in.args[0].size = sizeof(inarg);
	req->in.args[0].value = &inarg;
	req->in.args[1].size = strlen(name) + 1;
	req->in.args[1].value = name;
	req->in.args[2].size = size;
	req->in.args[2].value = value;
	request_send(fc, req);
	err = req->out.h.error;
	fuse_put_request(fc, req);
	if (err == -ENOSYS) {
		fc->no_setxattr = 1;
		err = -EOPNOTSUPP;
	}
	return err;
}

static ssize_t fuse_getxattr(struct dentry *entry, const char *name,
			     void *value, size_t size)
{
	struct inode *inode = entry->d_inode;
	struct fuse_conn *fc = get_fuse_conn(inode);
	struct fuse_req *req;
	struct fuse_getxattr_in inarg;
	struct fuse_getxattr_out outarg;
	ssize_t ret;

	if (fc->no_getxattr)
		return -EOPNOTSUPP;

	req = fuse_get_request(fc);
	if (!req)
		return -EINTR;

	memset(&inarg, 0, sizeof(inarg));
	inarg.size = size;
	req->in.h.opcode = FUSE_GETXATTR;
	req->in.h.nodeid = get_node_id(inode);
	req->inode = inode;
	req->in.numargs = 2;
	req->in.args[0].size = sizeof(inarg);
	req->in.args[0].value = &inarg;
	req->in.args[1].size = strlen(name) + 1;
	req->in.args[1].value = name;
	/* This is really two different operations rolled into one */
	req->out.numargs = 1;
	if (size) {
		req->out.argvar = 1;
		req->out.args[0].size = size;
		req->out.args[0].value = value;
	} else {
		req->out.args[0].size = sizeof(outarg);
		req->out.args[0].value = &outarg;
	}
	request_send(fc, req);
	ret = req->out.h.error;
	if (!ret)
		ret = size ? req->out.args[0].size : outarg.size;
	else {
		if (ret == -ENOSYS) {
			fc->no_getxattr = 1;
			ret = -EOPNOTSUPP;
		}
	}
	fuse_put_request(fc, req);
	return ret;
}

static ssize_t fuse_listxattr(struct dentry *entry, char *list, size_t size)
{
	struct inode *inode = entry->d_inode;
	struct fuse_conn *fc = get_fuse_conn(inode);
	struct fuse_req *req;
	struct fuse_getxattr_in inarg;
	struct fuse_getxattr_out outarg;
	ssize_t ret;

	if (fc->no_listxattr)
		return -EOPNOTSUPP;

	req = fuse_get_request(fc);
	if (!req)
		return -EINTR;

	memset(&inarg, 0, sizeof(inarg));
	inarg.size = size;
	req->in.h.opcode = FUSE_LISTXATTR;
	req->in.h.nodeid = get_node_id(inode);
	req->inode = inode;
	req->in.numargs = 1;
	req->in.args[0].size = sizeof(inarg);
	req->in.args[0].value = &inarg;
	/* This is really two different operations rolled into one */
	req->out.numargs = 1;
	if (size) {
		req->out.argvar = 1;
		req->out.args[0].size = size;
		req->out.args[0].value = list;
	} else {
		req->out.args[0].size = sizeof(outarg);
		req->out.args[0].value = &outarg;
	}
	request_send(fc, req);
	ret = req->out.h.error;
	if (!ret)
		ret = size ? req->out.args[0].size : outarg.size;
	else {
		if (ret == -ENOSYS) {
			fc->no_listxattr = 1;
			ret = -EOPNOTSUPP;
		}
	}
	fuse_put_request(fc, req);
	return ret;
}

static int fuse_removexattr(struct dentry *entry, const char *name)
{
	struct inode *inode = entry->d_inode;
	struct fuse_conn *fc = get_fuse_conn(inode);
	struct fuse_req *req;
	int err;

	if (fc->no_removexattr)
		return -EOPNOTSUPP;

	req = fuse_get_request(fc);
	if (!req)
		return -EINTR;

	req->in.h.opcode = FUSE_REMOVEXATTR;
	req->in.h.nodeid = get_node_id(inode);
	req->inode = inode;
	req->in.numargs = 1;
	req->in.args[0].size = strlen(name) + 1;
	req->in.args[0].value = name;
	request_send(fc, req);
	err = req->out.h.error;
	fuse_put_request(fc, req);
	if (err == -ENOSYS) {
		fc->no_removexattr = 1;
		err = -EOPNOTSUPP;
	}
	return err;
}
#endif

static struct inode_operations fuse_dir_inode_operations = {
#ifdef KERNEL_2_6
	.lookup		= fuse_lookup,
#else
	.lookup		= fuse_lookup_2_4,
#endif
	.mkdir		= fuse_mkdir,
	.symlink	= fuse_symlink,
	.unlink		= fuse_unlink,
	.rmdir		= fuse_rmdir,
	.rename		= fuse_rename,
	.link		= fuse_link,
	.setattr	= fuse_setattr,
#ifdef KERNEL_2_6
	.create		= fuse_create,
	.mknod		= fuse_mknod,
	.permission	= fuse_permission,
	.getattr	= fuse_getattr,
#else
	.create		= fuse_create_2_4,
	.mknod		= fuse_mknod_2_4,
	.permission	= fuse_permission_2_4,
	.revalidate	= fuse_revalidate,
#endif
#ifdef HAVE_KERNEL_XATTR
	.setxattr	= fuse_setxattr,
	.getxattr	= fuse_getxattr,
	.listxattr	= fuse_listxattr,
	.removexattr	= fuse_removexattr,
#endif
};

static struct file_operations fuse_dir_operations = {
	.llseek		= generic_file_llseek,
	.read		= generic_read_dir,
	.readdir	= fuse_readdir,
	.open		= fuse_dir_open,
	.release	= fuse_dir_release,
	.fsync		= fuse_dir_fsync,
};

static struct inode_operations fuse_common_inode_operations = {
	.setattr	= fuse_setattr,
#ifdef KERNEL_2_6
	.permission	= fuse_permission,
	.getattr	= fuse_getattr,
#else
	.permission	= fuse_permission_2_4,
	.revalidate	= fuse_revalidate,
#endif
#ifdef HAVE_KERNEL_XATTR
	.setxattr	= fuse_setxattr,
	.getxattr	= fuse_getxattr,
	.listxattr	= fuse_listxattr,
	.removexattr	= fuse_removexattr,
#endif
};

static struct inode_operations fuse_symlink_inode_operations = {
	.setattr	= fuse_setattr,
	.follow_link	= fuse_follow_link,
#ifdef KERNEL_2_6_8_PLUS
	.put_link	= fuse_put_link,
	.readlink	= generic_readlink,
#else
	.readlink	= fuse_readlink,
#endif
#ifdef KERNEL_2_6
	.getattr	= fuse_getattr,
#else
	.revalidate	= fuse_revalidate,
#endif
#ifdef HAVE_KERNEL_XATTR
	.setxattr	= fuse_setxattr,
	.getxattr	= fuse_getxattr,
	.listxattr	= fuse_listxattr,
	.removexattr	= fuse_removexattr,
#endif
};

void fuse_init_common(struct inode *inode)
{
	inode->i_op = &fuse_common_inode_operations;
}

void fuse_init_dir(struct inode *inode)
{
	inode->i_op = &fuse_dir_inode_operations;
	inode->i_fop = &fuse_dir_operations;
}

void fuse_init_symlink(struct inode *inode)
{
	inode->i_op = &fuse_symlink_inode_operations;
}