/*
* NBD Internal Declarations
*
* Copyright (C) 2016 Red Hat, Inc.
*
* This work is licensed under the terms of the GNU GPL, version 2 or later.
* See the COPYING file in the top-level directory.
*/
#ifndef NBD_INTERNAL_H
#define NBD_INTERNAL_H
#include "block/nbd.h"
#include "sysemu/block-backend.h"
#include "io/channel-tls.h"
#include "qemu/coroutine.h"
#include "qemu/iov.h"
#ifndef _WIN32
#include <sys/ioctl.h>
#endif
#if defined(__sun__) || defined(__HAIKU__)
#include <sys/ioccom.h>
#endif
#ifdef __linux__
#include <linux/fs.h>
#endif
#include "qemu/bswap.h"
#include "qemu/queue.h"
#include "qemu/main-loop.h"
/* This is all part of the "official" NBD API.
*
* The most up-to-date documentation is available at:
* https://github.com/yoe/nbd/blob/master/doc/proto.md
*/
/* Size of all NBD_OPT_*, without payload */
#define NBD_REQUEST_SIZE (4 + 2 + 2 + 8 + 8 + 4)
/* Size of all NBD_REP_* sent in answer to most NBD_OPT_*, without payload */
#define NBD_REPLY_SIZE (4 + 4 + 8)
#define NBD_REQUEST_MAGIC 0x25609513
#define NBD_REPLY_MAGIC 0x67446698
#define NBD_OPTS_MAGIC 0x49484156454F5054LL
#define NBD_CLIENT_MAGIC 0x0000420281861253LL
#define NBD_REP_MAGIC 0x0003e889045565a9LL
#define NBD_SET_SOCK _IO(0xab, 0)
#define NBD_SET_BLKSIZE _IO(0xab, 1)
#define NBD_SET_SIZE _IO(0xab, 2)
#define NBD_DO_IT _IO(0xab, 3)
#define NBD_CLEAR_SOCK _IO(0xab, 4)
#define NBD_CLEAR_QUE _IO(0xab, 5)
#define NBD_PRINT_DEBUG _IO(0xab, 6)
#define NBD_SET_SIZE_BLOCKS _IO(0xab, 7)
#define NBD_DISCONNECT _IO(0xab, 8)
#define NBD_SET_TIMEOUT _IO(0xab, 9)
#define NBD_SET_FLAGS _IO(0xab, 10)
/* NBD errors are based on errno numbers, so there is a 1:1 mapping,
* but only a limited set of errno values is specified in the protocol.
* Everything else is squashed to EINVAL.
*/
#define NBD_SUCCESS 0
#define NBD_EPERM 1
#define NBD_EIO 5
#define NBD_ENOMEM 12
#define NBD_EINVAL 22
#define NBD_ENOSPC 28
#define NBD_ESHUTDOWN 108
/* nbd_read_eof
* Tries to read @size bytes from @ioc. Returns number of bytes actually read.
* May return a value >= 0 and < size only on EOF, i.e. when iteratively called
* qio_channel_readv() returns 0. So, there is no need to call nbd_read_eof
* iteratively.
*/
static inline ssize_t nbd_read_eof(QIOChannel *ioc, void *buffer, size_t size,
Error **errp)
{
struct iovec iov = { .iov_base = buffer, .iov_len = size };
/* Sockets are kept in blocking mode in the negotiation phase. After
* that, a non-readable socket simply means that another thread stole
* our request/reply. Synchronization is done with recv_coroutine, so
* that this is coroutine-safe.
*/
return nbd_rwv(ioc, &iov, 1, size, true, errp);
}
/* nbd_read
* Reads @size bytes from @ioc. Returns 0 on success.
*/
static inline int nbd_read(QIOChannel *ioc, void *buffer, size_t size,
Error **errp)
{
ssize_t ret = nbd_read_eof(ioc, buffer, size, errp);
if (ret >= 0 && ret != size) {
ret = -EINVAL;
error_setg(errp, "End of file");
}
return ret < 0 ? ret : 0;
}
/* nbd_write
* Writes @size bytes to @ioc. Returns 0 on success.
*/
static inline int nbd_write(QIOChannel *ioc, const void *buffer, size_t size,
Error **errp)
{
struct iovec iov = { .iov_base = (void *) buffer, .iov_len = size };
ssize_t ret = nbd_rwv(ioc, &iov, 1, size, false, errp);
assert(ret < 0 || ret == size);
return ret < 0 ? ret : 0;
}
struct NBDTLSHandshakeData {
GMainLoop *loop;
bool complete;
Error *error;
};
void nbd_tls_handshake(QIOTask *task,
void *opaque);
const char *nbd_opt_lookup(uint32_t opt);
const char *nbd_rep_lookup(uint32_t rep);
const char *nbd_info_lookup(uint16_t info);
const char *nbd_cmd_lookup(uint16_t info);
int nbd_drop(QIOChannel *ioc, size_t size, Error **errp);
#endif
