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Diffstat (limited to 'nbd/nbd-internal.h')
-rw-r--r-- | nbd/nbd-internal.h | 113 |
1 files changed, 113 insertions, 0 deletions
diff --git a/nbd/nbd-internal.h b/nbd/nbd-internal.h new file mode 100644 index 0000000000..c0a657575b --- /dev/null +++ b/nbd/nbd-internal.h @@ -0,0 +1,113 @@ +/* + * 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 "qemu/coroutine.h" + +#include <errno.h> +#include <string.h> +#ifndef _WIN32 +#include <sys/ioctl.h> +#endif +#if defined(__sun__) || defined(__HAIKU__) +#include <sys/ioccom.h> +#endif +#include <ctype.h> +#include <inttypes.h> + +#ifdef __linux__ +#include <linux/fs.h> +#endif + +#include "qemu/sockets.h" +#include "qemu/queue.h" +#include "qemu/main-loop.h" + +/* #define DEBUG_NBD */ + +#ifdef DEBUG_NBD +#define TRACE(msg, ...) do { \ + LOG(msg, ## __VA_ARGS__); \ +} while(0) +#else +#define TRACE(msg, ...) \ + do { } while (0) +#endif + +#define LOG(msg, ...) do { \ + fprintf(stderr, "%s:%s():L%d: " msg "\n", \ + __FILE__, __FUNCTION__, __LINE__, ## __VA_ARGS__); \ +} while(0) + +/* 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.txt + */ + +#define NBD_REQUEST_SIZE (4 + 4 + 8 + 8 + 4) +#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 0x3e889045565a9LL + +#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) + +#define NBD_OPT_EXPORT_NAME (1) +#define NBD_OPT_ABORT (2) +#define NBD_OPT_LIST (3) + +/* 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 + +static inline ssize_t read_sync(int fd, void *buffer, size_t 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_wr_sync(fd, buffer, size, true); +} + +static inline ssize_t write_sync(int fd, void *buffer, size_t size) +{ + int ret; + do { + /* For writes, we do expect the socket to be writable. */ + ret = nbd_wr_sync(fd, buffer, size, false); + } while (ret == -EAGAIN); + return ret; +} + +#endif |