412 lines
15 KiB
C
412 lines
15 KiB
C
/*
|
|
* Copyright (C) 2016-2019 Red Hat, Inc.
|
|
* Copyright (C) 2005 Anthony Liguori <anthony@codemonkey.ws>
|
|
*
|
|
* Network Block Device
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License as published by
|
|
* the Free Software Foundation; under version 2 of the License.
|
|
*
|
|
* This program is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
* GNU General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU General Public License
|
|
* along with this program; if not, see <http://www.gnu.org/licenses/>.
|
|
*/
|
|
|
|
#ifndef NBD_H
|
|
#define NBD_H
|
|
|
|
#include "qapi/qapi-types-block.h"
|
|
#include "io/channel-socket.h"
|
|
#include "crypto/tlscreds.h"
|
|
#include "qapi/error.h"
|
|
|
|
/* Handshake phase structs - this struct is passed on the wire */
|
|
|
|
struct NBDOption {
|
|
uint64_t magic; /* NBD_OPTS_MAGIC */
|
|
uint32_t option; /* NBD_OPT_* */
|
|
uint32_t length;
|
|
} QEMU_PACKED;
|
|
typedef struct NBDOption NBDOption;
|
|
|
|
struct NBDOptionReply {
|
|
uint64_t magic; /* NBD_REP_MAGIC */
|
|
uint32_t option; /* NBD_OPT_* */
|
|
uint32_t type; /* NBD_REP_* */
|
|
uint32_t length;
|
|
} QEMU_PACKED;
|
|
typedef struct NBDOptionReply NBDOptionReply;
|
|
|
|
typedef struct NBDOptionReplyMetaContext {
|
|
NBDOptionReply h; /* h.type = NBD_REP_META_CONTEXT, h.length > 4 */
|
|
uint32_t context_id;
|
|
/* meta context name follows */
|
|
} QEMU_PACKED NBDOptionReplyMetaContext;
|
|
|
|
/* Transmission phase structs
|
|
*
|
|
* Note: these are _NOT_ the same as the network representation of an NBD
|
|
* request and reply!
|
|
*/
|
|
struct NBDRequest {
|
|
uint64_t handle;
|
|
uint64_t from;
|
|
uint32_t len;
|
|
uint16_t flags; /* NBD_CMD_FLAG_* */
|
|
uint16_t type; /* NBD_CMD_* */
|
|
};
|
|
typedef struct NBDRequest NBDRequest;
|
|
|
|
typedef struct NBDSimpleReply {
|
|
uint32_t magic; /* NBD_SIMPLE_REPLY_MAGIC */
|
|
uint32_t error;
|
|
uint64_t handle;
|
|
} QEMU_PACKED NBDSimpleReply;
|
|
|
|
/* Header of all structured replies */
|
|
typedef struct NBDStructuredReplyChunk {
|
|
uint32_t magic; /* NBD_STRUCTURED_REPLY_MAGIC */
|
|
uint16_t flags; /* combination of NBD_REPLY_FLAG_* */
|
|
uint16_t type; /* NBD_REPLY_TYPE_* */
|
|
uint64_t handle; /* request handle */
|
|
uint32_t length; /* length of payload */
|
|
} QEMU_PACKED NBDStructuredReplyChunk;
|
|
|
|
typedef union NBDReply {
|
|
NBDSimpleReply simple;
|
|
NBDStructuredReplyChunk structured;
|
|
struct {
|
|
/* @magic and @handle fields have the same offset and size both in
|
|
* simple reply and structured reply chunk, so let them be accessible
|
|
* without ".simple." or ".structured." specification
|
|
*/
|
|
uint32_t magic;
|
|
uint32_t _skip;
|
|
uint64_t handle;
|
|
} QEMU_PACKED;
|
|
} NBDReply;
|
|
|
|
/* Header of chunk for NBD_REPLY_TYPE_OFFSET_DATA */
|
|
typedef struct NBDStructuredReadData {
|
|
NBDStructuredReplyChunk h; /* h.length >= 9 */
|
|
uint64_t offset;
|
|
/* At least one byte of data payload follows, calculated from h.length */
|
|
} QEMU_PACKED NBDStructuredReadData;
|
|
|
|
/* Complete chunk for NBD_REPLY_TYPE_OFFSET_HOLE */
|
|
typedef struct NBDStructuredReadHole {
|
|
NBDStructuredReplyChunk h; /* h.length == 12 */
|
|
uint64_t offset;
|
|
uint32_t length;
|
|
} QEMU_PACKED NBDStructuredReadHole;
|
|
|
|
/* Header of all NBD_REPLY_TYPE_ERROR* errors */
|
|
typedef struct NBDStructuredError {
|
|
NBDStructuredReplyChunk h; /* h.length >= 6 */
|
|
uint32_t error;
|
|
uint16_t message_length;
|
|
} QEMU_PACKED NBDStructuredError;
|
|
|
|
/* Header of NBD_REPLY_TYPE_BLOCK_STATUS */
|
|
typedef struct NBDStructuredMeta {
|
|
NBDStructuredReplyChunk h; /* h.length >= 12 (at least one extent) */
|
|
uint32_t context_id;
|
|
/* extents follows */
|
|
} QEMU_PACKED NBDStructuredMeta;
|
|
|
|
/* Extent chunk for NBD_REPLY_TYPE_BLOCK_STATUS */
|
|
typedef struct NBDExtent {
|
|
uint32_t length;
|
|
uint32_t flags; /* NBD_STATE_* */
|
|
} QEMU_PACKED NBDExtent;
|
|
|
|
/* Transmission (export) flags: sent from server to client during handshake,
|
|
but describe what will happen during transmission */
|
|
enum {
|
|
NBD_FLAG_HAS_FLAGS_BIT = 0, /* Flags are there */
|
|
NBD_FLAG_READ_ONLY_BIT = 1, /* Device is read-only */
|
|
NBD_FLAG_SEND_FLUSH_BIT = 2, /* Send FLUSH */
|
|
NBD_FLAG_SEND_FUA_BIT = 3, /* Send FUA (Force Unit Access) */
|
|
NBD_FLAG_ROTATIONAL_BIT = 4, /* Use elevator algorithm -
|
|
rotational media */
|
|
NBD_FLAG_SEND_TRIM_BIT = 5, /* Send TRIM (discard) */
|
|
NBD_FLAG_SEND_WRITE_ZEROES_BIT = 6, /* Send WRITE_ZEROES */
|
|
NBD_FLAG_SEND_DF_BIT = 7, /* Send DF (Do not Fragment) */
|
|
NBD_FLAG_CAN_MULTI_CONN_BIT = 8, /* Multi-client cache consistent */
|
|
NBD_FLAG_SEND_RESIZE_BIT = 9, /* Send resize */
|
|
NBD_FLAG_SEND_CACHE_BIT = 10, /* Send CACHE (prefetch) */
|
|
NBD_FLAG_SEND_FAST_ZERO_BIT = 11, /* FAST_ZERO flag for WRITE_ZEROES */
|
|
};
|
|
|
|
#define NBD_FLAG_HAS_FLAGS (1 << NBD_FLAG_HAS_FLAGS_BIT)
|
|
#define NBD_FLAG_READ_ONLY (1 << NBD_FLAG_READ_ONLY_BIT)
|
|
#define NBD_FLAG_SEND_FLUSH (1 << NBD_FLAG_SEND_FLUSH_BIT)
|
|
#define NBD_FLAG_SEND_FUA (1 << NBD_FLAG_SEND_FUA_BIT)
|
|
#define NBD_FLAG_ROTATIONAL (1 << NBD_FLAG_ROTATIONAL_BIT)
|
|
#define NBD_FLAG_SEND_TRIM (1 << NBD_FLAG_SEND_TRIM_BIT)
|
|
#define NBD_FLAG_SEND_WRITE_ZEROES (1 << NBD_FLAG_SEND_WRITE_ZEROES_BIT)
|
|
#define NBD_FLAG_SEND_DF (1 << NBD_FLAG_SEND_DF_BIT)
|
|
#define NBD_FLAG_CAN_MULTI_CONN (1 << NBD_FLAG_CAN_MULTI_CONN_BIT)
|
|
#define NBD_FLAG_SEND_RESIZE (1 << NBD_FLAG_SEND_RESIZE_BIT)
|
|
#define NBD_FLAG_SEND_CACHE (1 << NBD_FLAG_SEND_CACHE_BIT)
|
|
#define NBD_FLAG_SEND_FAST_ZERO (1 << NBD_FLAG_SEND_FAST_ZERO_BIT)
|
|
|
|
/* New-style handshake (global) flags, sent from server to client, and
|
|
control what will happen during handshake phase. */
|
|
#define NBD_FLAG_FIXED_NEWSTYLE (1 << 0) /* Fixed newstyle protocol. */
|
|
#define NBD_FLAG_NO_ZEROES (1 << 1) /* End handshake without zeroes. */
|
|
|
|
/* New-style client flags, sent from client to server to control what happens
|
|
during handshake phase. */
|
|
#define NBD_FLAG_C_FIXED_NEWSTYLE (1 << 0) /* Fixed newstyle protocol. */
|
|
#define NBD_FLAG_C_NO_ZEROES (1 << 1) /* End handshake without zeroes. */
|
|
|
|
/* Option requests. */
|
|
#define NBD_OPT_EXPORT_NAME (1)
|
|
#define NBD_OPT_ABORT (2)
|
|
#define NBD_OPT_LIST (3)
|
|
/* #define NBD_OPT_PEEK_EXPORT (4) not in use */
|
|
#define NBD_OPT_STARTTLS (5)
|
|
#define NBD_OPT_INFO (6)
|
|
#define NBD_OPT_GO (7)
|
|
#define NBD_OPT_STRUCTURED_REPLY (8)
|
|
#define NBD_OPT_LIST_META_CONTEXT (9)
|
|
#define NBD_OPT_SET_META_CONTEXT (10)
|
|
|
|
/* Option reply types. */
|
|
#define NBD_REP_ERR(value) ((UINT32_C(1) << 31) | (value))
|
|
|
|
#define NBD_REP_ACK (1) /* Data sending finished. */
|
|
#define NBD_REP_SERVER (2) /* Export description. */
|
|
#define NBD_REP_INFO (3) /* NBD_OPT_INFO/GO. */
|
|
#define NBD_REP_META_CONTEXT (4) /* NBD_OPT_{LIST,SET}_META_CONTEXT */
|
|
|
|
#define NBD_REP_ERR_UNSUP NBD_REP_ERR(1) /* Unknown option */
|
|
#define NBD_REP_ERR_POLICY NBD_REP_ERR(2) /* Server denied */
|
|
#define NBD_REP_ERR_INVALID NBD_REP_ERR(3) /* Invalid length */
|
|
#define NBD_REP_ERR_PLATFORM NBD_REP_ERR(4) /* Not compiled in */
|
|
#define NBD_REP_ERR_TLS_REQD NBD_REP_ERR(5) /* TLS required */
|
|
#define NBD_REP_ERR_UNKNOWN NBD_REP_ERR(6) /* Export unknown */
|
|
#define NBD_REP_ERR_SHUTDOWN NBD_REP_ERR(7) /* Server shutting down */
|
|
#define NBD_REP_ERR_BLOCK_SIZE_REQD NBD_REP_ERR(8) /* Need INFO_BLOCK_SIZE */
|
|
|
|
/* Info types, used during NBD_REP_INFO */
|
|
#define NBD_INFO_EXPORT 0
|
|
#define NBD_INFO_NAME 1
|
|
#define NBD_INFO_DESCRIPTION 2
|
|
#define NBD_INFO_BLOCK_SIZE 3
|
|
|
|
/* Request flags, sent from client to server during transmission phase */
|
|
#define NBD_CMD_FLAG_FUA (1 << 0) /* 'force unit access' during write */
|
|
#define NBD_CMD_FLAG_NO_HOLE (1 << 1) /* don't punch hole on zero run */
|
|
#define NBD_CMD_FLAG_DF (1 << 2) /* don't fragment structured read */
|
|
#define NBD_CMD_FLAG_REQ_ONE (1 << 3) /* only one extent in BLOCK_STATUS
|
|
* reply chunk */
|
|
#define NBD_CMD_FLAG_FAST_ZERO (1 << 4) /* fail if WRITE_ZEROES is not fast */
|
|
|
|
/* Supported request types */
|
|
enum {
|
|
NBD_CMD_READ = 0,
|
|
NBD_CMD_WRITE = 1,
|
|
NBD_CMD_DISC = 2,
|
|
NBD_CMD_FLUSH = 3,
|
|
NBD_CMD_TRIM = 4,
|
|
NBD_CMD_CACHE = 5,
|
|
NBD_CMD_WRITE_ZEROES = 6,
|
|
NBD_CMD_BLOCK_STATUS = 7,
|
|
};
|
|
|
|
#define NBD_DEFAULT_PORT 10809
|
|
|
|
/* Maximum size of a single READ/WRITE data buffer */
|
|
#define NBD_MAX_BUFFER_SIZE (32 * 1024 * 1024)
|
|
|
|
/*
|
|
* Maximum size of a protocol string (export name, meta context name,
|
|
* etc.). Use malloc rather than stack allocation for storage of a
|
|
* string.
|
|
*/
|
|
#define NBD_MAX_STRING_SIZE 4096
|
|
|
|
/* Two types of reply structures */
|
|
#define NBD_SIMPLE_REPLY_MAGIC 0x67446698
|
|
#define NBD_STRUCTURED_REPLY_MAGIC 0x668e33ef
|
|
|
|
/* Structured reply flags */
|
|
#define NBD_REPLY_FLAG_DONE (1 << 0) /* This reply-chunk is last */
|
|
|
|
/* Structured reply types */
|
|
#define NBD_REPLY_ERR(value) ((1 << 15) | (value))
|
|
|
|
#define NBD_REPLY_TYPE_NONE 0
|
|
#define NBD_REPLY_TYPE_OFFSET_DATA 1
|
|
#define NBD_REPLY_TYPE_OFFSET_HOLE 2
|
|
#define NBD_REPLY_TYPE_BLOCK_STATUS 5
|
|
#define NBD_REPLY_TYPE_ERROR NBD_REPLY_ERR(1)
|
|
#define NBD_REPLY_TYPE_ERROR_OFFSET NBD_REPLY_ERR(2)
|
|
|
|
/* Extent flags for base:allocation in NBD_REPLY_TYPE_BLOCK_STATUS */
|
|
#define NBD_STATE_HOLE (1 << 0)
|
|
#define NBD_STATE_ZERO (1 << 1)
|
|
|
|
/* Extent flags for qemu:dirty-bitmap in NBD_REPLY_TYPE_BLOCK_STATUS */
|
|
#define NBD_STATE_DIRTY (1 << 0)
|
|
|
|
static inline bool nbd_reply_type_is_error(int type)
|
|
{
|
|
return type & (1 << 15);
|
|
}
|
|
|
|
/* 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_EOVERFLOW 75
|
|
#define NBD_ENOTSUP 95
|
|
#define NBD_ESHUTDOWN 108
|
|
|
|
/* Details collected by NBD_OPT_EXPORT_NAME and NBD_OPT_GO */
|
|
struct NBDExportInfo {
|
|
/* Set by client before nbd_receive_negotiate() */
|
|
bool request_sizes;
|
|
char *x_dirty_bitmap;
|
|
|
|
/* Set by client before nbd_receive_negotiate(), or by server results
|
|
* during nbd_receive_export_list() */
|
|
char *name; /* must be non-NULL */
|
|
|
|
/* In-out fields, set by client before nbd_receive_negotiate() and
|
|
* updated by server results during nbd_receive_negotiate() */
|
|
bool structured_reply;
|
|
bool base_allocation; /* base:allocation context for NBD_CMD_BLOCK_STATUS */
|
|
|
|
/* Set by server results during nbd_receive_negotiate() and
|
|
* nbd_receive_export_list() */
|
|
uint64_t size;
|
|
uint16_t flags;
|
|
uint32_t min_block;
|
|
uint32_t opt_block;
|
|
uint32_t max_block;
|
|
|
|
uint32_t context_id;
|
|
|
|
/* Set by server results during nbd_receive_export_list() */
|
|
char *description;
|
|
int n_contexts;
|
|
char **contexts;
|
|
};
|
|
typedef struct NBDExportInfo NBDExportInfo;
|
|
|
|
int nbd_receive_negotiate(AioContext *aio_context, QIOChannel *ioc,
|
|
QCryptoTLSCreds *tlscreds,
|
|
const char *hostname, QIOChannel **outioc,
|
|
NBDExportInfo *info, Error **errp);
|
|
void nbd_free_export_list(NBDExportInfo *info, int count);
|
|
int nbd_receive_export_list(QIOChannel *ioc, QCryptoTLSCreds *tlscreds,
|
|
const char *hostname, NBDExportInfo **info,
|
|
Error **errp);
|
|
int nbd_init(int fd, QIOChannelSocket *sioc, NBDExportInfo *info,
|
|
Error **errp);
|
|
int nbd_send_request(QIOChannel *ioc, NBDRequest *request);
|
|
int coroutine_fn nbd_receive_reply(BlockDriverState *bs, QIOChannel *ioc,
|
|
NBDReply *reply, Error **errp);
|
|
int nbd_client(int fd);
|
|
int nbd_disconnect(int fd);
|
|
int nbd_errno_to_system_errno(int err);
|
|
|
|
typedef struct NBDExport NBDExport;
|
|
typedef struct NBDClient NBDClient;
|
|
|
|
NBDExport *nbd_export_new(BlockDriverState *bs, uint64_t dev_offset,
|
|
uint64_t size, const char *name, const char *desc,
|
|
const char *bitmap, bool readonly, bool shared,
|
|
void (*close)(NBDExport *), bool writethrough,
|
|
BlockBackend *on_eject_blk, Error **errp);
|
|
void nbd_export_close(NBDExport *exp);
|
|
void nbd_export_remove(NBDExport *exp, NbdServerRemoveMode mode, Error **errp);
|
|
void nbd_export_get(NBDExport *exp);
|
|
void nbd_export_put(NBDExport *exp);
|
|
|
|
BlockBackend *nbd_export_get_blockdev(NBDExport *exp);
|
|
|
|
AioContext *nbd_export_aio_context(NBDExport *exp);
|
|
NBDExport *nbd_export_find(const char *name);
|
|
void nbd_export_close_all(void);
|
|
|
|
void nbd_client_new(QIOChannelSocket *sioc,
|
|
QCryptoTLSCreds *tlscreds,
|
|
const char *tlsauthz,
|
|
void (*close_fn)(NBDClient *, bool));
|
|
void nbd_client_get(NBDClient *client);
|
|
void nbd_client_put(NBDClient *client);
|
|
|
|
void nbd_server_start(SocketAddress *addr, const char *tls_creds,
|
|
const char *tls_authz, Error **errp);
|
|
void nbd_server_start_options(NbdServerOptions *arg, Error **errp);
|
|
|
|
/* nbd_read
|
|
* Reads @size bytes from @ioc. Returns 0 on success.
|
|
*/
|
|
static inline int nbd_read(QIOChannel *ioc, void *buffer, size_t size,
|
|
const char *desc, Error **errp)
|
|
{
|
|
ERRP_GUARD();
|
|
int ret = qio_channel_read_all(ioc, buffer, size, errp) < 0 ? -EIO : 0;
|
|
|
|
if (ret < 0) {
|
|
if (desc) {
|
|
error_prepend(errp, "Failed to read %s: ", desc);
|
|
}
|
|
return -1;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
#define DEF_NBD_READ_N(bits) \
|
|
static inline int nbd_read##bits(QIOChannel *ioc, \
|
|
uint##bits##_t *val, \
|
|
const char *desc, Error **errp) \
|
|
{ \
|
|
if (nbd_read(ioc, val, sizeof(*val), desc, errp) < 0) { \
|
|
return -1; \
|
|
} \
|
|
*val = be##bits##_to_cpu(*val); \
|
|
return 0; \
|
|
}
|
|
|
|
DEF_NBD_READ_N(16) /* Defines nbd_read16(). */
|
|
DEF_NBD_READ_N(32) /* Defines nbd_read32(). */
|
|
DEF_NBD_READ_N(64) /* Defines nbd_read64(). */
|
|
|
|
#undef DEF_NBD_READ_N
|
|
|
|
static inline bool nbd_reply_is_simple(NBDReply *reply)
|
|
{
|
|
return reply->magic == NBD_SIMPLE_REPLY_MAGIC;
|
|
}
|
|
|
|
static inline bool nbd_reply_is_structured(NBDReply *reply)
|
|
{
|
|
return reply->magic == NBD_STRUCTURED_REPLY_MAGIC;
|
|
}
|
|
|
|
const char *nbd_reply_type_lookup(uint16_t type);
|
|
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);
|
|
const char *nbd_err_lookup(int err);
|
|
|
|
#endif
|