/* * 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 "qemu-common.h" #include "qemu/option.h" #include "io/channel-socket.h" #include "crypto/tlscreds.h" /* Note: these are _NOT_ the same as the network representation of an NBD * request and reply! */ struct nbd_request { uint64_t handle; uint64_t from; uint32_t len; uint32_t type; }; struct nbd_reply { uint64_t handle; uint32_t error; }; #define NBD_FLAG_HAS_FLAGS (1 << 0) /* Flags are there */ #define NBD_FLAG_READ_ONLY (1 << 1) /* Device is read-only */ #define NBD_FLAG_SEND_FLUSH (1 << 2) /* Send FLUSH */ #define NBD_FLAG_SEND_FUA (1 << 3) /* Send FUA (Force Unit Access) */ #define NBD_FLAG_ROTATIONAL (1 << 4) /* Use elevator algorithm - rotational media */ #define NBD_FLAG_SEND_TRIM (1 << 5) /* Send TRIM (discard) */ /* New-style global flags. */ #define NBD_FLAG_FIXED_NEWSTYLE (1 << 0) /* Fixed newstyle protocol. */ /* New-style client flags. */ #define NBD_FLAG_C_FIXED_NEWSTYLE (1 << 0) /* Fixed newstyle protocol. */ /* Reply types. */ #define NBD_REP_ACK (1) /* Data sending finished. */ #define NBD_REP_SERVER (2) /* Export description. */ #define NBD_REP_ERR_UNSUP ((UINT32_C(1) << 31) | 1) /* Unknown option. */ #define NBD_REP_ERR_POLICY ((UINT32_C(1) << 31) | 2) /* Server denied */ #define NBD_REP_ERR_INVALID ((UINT32_C(1) << 31) | 3) /* Invalid length. */ #define NBD_REP_ERR_TLS_REQD ((UINT32_C(1) << 31) | 5) /* TLS required */ #define NBD_CMD_MASK_COMMAND 0x0000ffff #define NBD_CMD_FLAG_FUA (1 << 16) enum { NBD_CMD_READ = 0, NBD_CMD_WRITE = 1, NBD_CMD_DISC = 2, NBD_CMD_FLUSH = 3, NBD_CMD_TRIM = 4 }; #define NBD_DEFAULT_PORT 10809 /* Maximum size of a single READ/WRITE data buffer */ #define NBD_MAX_BUFFER_SIZE (32 * 1024 * 1024) #define NBD_MAX_SECTORS (NBD_MAX_BUFFER_SIZE / BDRV_SECTOR_SIZE) /* Maximum size of an export name. The NBD spec requires 256 and * suggests that servers support up to 4096, but we stick to only the * required size so that we can stack-allocate the names, and because * going larger would require an audit of more code to make sure we * aren't overflowing some other buffer. */ #define NBD_MAX_NAME_SIZE 256 ssize_t nbd_wr_syncv(QIOChannel *ioc, struct iovec *iov, size_t niov, size_t offset, size_t length, bool do_read); int nbd_receive_negotiate(QIOChannel *ioc, const char *name, uint32_t *flags, QCryptoTLSCreds *tlscreds, const char *hostname, QIOChannel **outioc, off_t *size, Error **errp); int nbd_init(int fd, QIOChannelSocket *sioc, uint32_t flags, off_t size); ssize_t nbd_send_request(QIOChannel *ioc, struct nbd_request *request); ssize_t nbd_receive_reply(QIOChannel *ioc, struct nbd_reply *reply); int nbd_client(int fd); int nbd_disconnect(int fd); typedef struct NBDExport NBDExport; typedef struct NBDClient NBDClient; NBDExport *nbd_export_new(BlockBackend *blk, off_t dev_offset, off_t size, uint32_t nbdflags, void (*close)(NBDExport *), Error **errp); void nbd_export_close(NBDExport *exp); void nbd_export_get(NBDExport *exp); void nbd_export_put(NBDExport *exp); BlockBackend *nbd_export_get_blockdev(NBDExport *exp); NBDExport *nbd_export_find(const char *name); void nbd_export_set_name(NBDExport *exp, const char *name); void nbd_export_close_all(void); void nbd_client_new(NBDExport *exp, QIOChannelSocket *sioc, QCryptoTLSCreds *tlscreds, const char *tlsaclname, void (*close)(NBDClient *)); void nbd_client_get(NBDClient *client); void nbd_client_put(NBDClient *client); #endif