3380 lines
103 KiB
C
3380 lines
103 KiB
C
/*
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* RDMA protocol and interfaces
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*
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* Copyright IBM, Corp. 2010-2013
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*
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* Authors:
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* Michael R. Hines <mrhines@us.ibm.com>
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* Jiuxing Liu <jl@us.ibm.com>
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*
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* This work is licensed under the terms of the GNU GPL, version 2 or
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* later. See the COPYING file in the top-level directory.
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*
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*/
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#include "qemu-common.h"
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#include "migration/migration.h"
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#include "migration/qemu-file.h"
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#include "exec/cpu-common.h"
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#include "qemu/main-loop.h"
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#include "qemu/sockets.h"
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#include "qemu/bitmap.h"
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#include "block/coroutine.h"
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#include <stdio.h>
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#include <sys/types.h>
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#include <sys/socket.h>
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#include <netdb.h>
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#include <arpa/inet.h>
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#include <string.h>
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#include <rdma/rdma_cma.h>
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#include "trace.h"
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/*
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* Print and error on both the Monitor and the Log file.
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*/
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#define ERROR(errp, fmt, ...) \
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do { \
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fprintf(stderr, "RDMA ERROR: " fmt "\n", ## __VA_ARGS__); \
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if (errp && (*(errp) == NULL)) { \
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error_setg(errp, "RDMA ERROR: " fmt, ## __VA_ARGS__); \
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} \
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} while (0)
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#define RDMA_RESOLVE_TIMEOUT_MS 10000
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/* Do not merge data if larger than this. */
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#define RDMA_MERGE_MAX (2 * 1024 * 1024)
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#define RDMA_SIGNALED_SEND_MAX (RDMA_MERGE_MAX / 4096)
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#define RDMA_REG_CHUNK_SHIFT 20 /* 1 MB */
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/*
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* This is only for non-live state being migrated.
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* Instead of RDMA_WRITE messages, we use RDMA_SEND
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* messages for that state, which requires a different
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* delivery design than main memory.
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*/
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#define RDMA_SEND_INCREMENT 32768
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/*
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* Maximum size infiniband SEND message
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*/
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#define RDMA_CONTROL_MAX_BUFFER (512 * 1024)
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#define RDMA_CONTROL_MAX_COMMANDS_PER_MESSAGE 4096
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#define RDMA_CONTROL_VERSION_CURRENT 1
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/*
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* Capabilities for negotiation.
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*/
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#define RDMA_CAPABILITY_PIN_ALL 0x01
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/*
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* Add the other flags above to this list of known capabilities
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* as they are introduced.
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*/
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static uint32_t known_capabilities = RDMA_CAPABILITY_PIN_ALL;
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#define CHECK_ERROR_STATE() \
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do { \
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if (rdma->error_state) { \
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if (!rdma->error_reported) { \
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error_report("RDMA is in an error state waiting migration" \
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" to abort!"); \
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rdma->error_reported = 1; \
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} \
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return rdma->error_state; \
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} \
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} while (0);
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/*
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* A work request ID is 64-bits and we split up these bits
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* into 3 parts:
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*
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* bits 0-15 : type of control message, 2^16
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* bits 16-29: ram block index, 2^14
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* bits 30-63: ram block chunk number, 2^34
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*
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* The last two bit ranges are only used for RDMA writes,
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* in order to track their completion and potentially
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* also track unregistration status of the message.
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*/
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#define RDMA_WRID_TYPE_SHIFT 0UL
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#define RDMA_WRID_BLOCK_SHIFT 16UL
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#define RDMA_WRID_CHUNK_SHIFT 30UL
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#define RDMA_WRID_TYPE_MASK \
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((1UL << RDMA_WRID_BLOCK_SHIFT) - 1UL)
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#define RDMA_WRID_BLOCK_MASK \
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(~RDMA_WRID_TYPE_MASK & ((1UL << RDMA_WRID_CHUNK_SHIFT) - 1UL))
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#define RDMA_WRID_CHUNK_MASK (~RDMA_WRID_BLOCK_MASK & ~RDMA_WRID_TYPE_MASK)
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/*
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* RDMA migration protocol:
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* 1. RDMA Writes (data messages, i.e. RAM)
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* 2. IB Send/Recv (control channel messages)
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*/
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enum {
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RDMA_WRID_NONE = 0,
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RDMA_WRID_RDMA_WRITE = 1,
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RDMA_WRID_SEND_CONTROL = 2000,
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RDMA_WRID_RECV_CONTROL = 4000,
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};
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static const char *wrid_desc[] = {
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[RDMA_WRID_NONE] = "NONE",
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[RDMA_WRID_RDMA_WRITE] = "WRITE RDMA",
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[RDMA_WRID_SEND_CONTROL] = "CONTROL SEND",
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[RDMA_WRID_RECV_CONTROL] = "CONTROL RECV",
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};
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/*
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* Work request IDs for IB SEND messages only (not RDMA writes).
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* This is used by the migration protocol to transmit
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* control messages (such as device state and registration commands)
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*
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* We could use more WRs, but we have enough for now.
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*/
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enum {
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RDMA_WRID_READY = 0,
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RDMA_WRID_DATA,
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RDMA_WRID_CONTROL,
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RDMA_WRID_MAX,
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};
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/*
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* SEND/RECV IB Control Messages.
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*/
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enum {
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RDMA_CONTROL_NONE = 0,
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RDMA_CONTROL_ERROR,
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RDMA_CONTROL_READY, /* ready to receive */
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RDMA_CONTROL_QEMU_FILE, /* QEMUFile-transmitted bytes */
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RDMA_CONTROL_RAM_BLOCKS_REQUEST, /* RAMBlock synchronization */
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RDMA_CONTROL_RAM_BLOCKS_RESULT, /* RAMBlock synchronization */
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RDMA_CONTROL_COMPRESS, /* page contains repeat values */
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RDMA_CONTROL_REGISTER_REQUEST, /* dynamic page registration */
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RDMA_CONTROL_REGISTER_RESULT, /* key to use after registration */
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RDMA_CONTROL_REGISTER_FINISHED, /* current iteration finished */
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RDMA_CONTROL_UNREGISTER_REQUEST, /* dynamic UN-registration */
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RDMA_CONTROL_UNREGISTER_FINISHED, /* unpinning finished */
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};
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static const char *control_desc[] = {
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[RDMA_CONTROL_NONE] = "NONE",
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[RDMA_CONTROL_ERROR] = "ERROR",
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[RDMA_CONTROL_READY] = "READY",
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[RDMA_CONTROL_QEMU_FILE] = "QEMU FILE",
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[RDMA_CONTROL_RAM_BLOCKS_REQUEST] = "RAM BLOCKS REQUEST",
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[RDMA_CONTROL_RAM_BLOCKS_RESULT] = "RAM BLOCKS RESULT",
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[RDMA_CONTROL_COMPRESS] = "COMPRESS",
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[RDMA_CONTROL_REGISTER_REQUEST] = "REGISTER REQUEST",
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[RDMA_CONTROL_REGISTER_RESULT] = "REGISTER RESULT",
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[RDMA_CONTROL_REGISTER_FINISHED] = "REGISTER FINISHED",
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[RDMA_CONTROL_UNREGISTER_REQUEST] = "UNREGISTER REQUEST",
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[RDMA_CONTROL_UNREGISTER_FINISHED] = "UNREGISTER FINISHED",
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};
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/*
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* Memory and MR structures used to represent an IB Send/Recv work request.
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* This is *not* used for RDMA writes, only IB Send/Recv.
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*/
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typedef struct {
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uint8_t control[RDMA_CONTROL_MAX_BUFFER]; /* actual buffer to register */
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struct ibv_mr *control_mr; /* registration metadata */
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size_t control_len; /* length of the message */
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uint8_t *control_curr; /* start of unconsumed bytes */
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} RDMAWorkRequestData;
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/*
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* Negotiate RDMA capabilities during connection-setup time.
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*/
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typedef struct {
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uint32_t version;
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uint32_t flags;
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} RDMACapabilities;
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static void caps_to_network(RDMACapabilities *cap)
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{
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cap->version = htonl(cap->version);
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cap->flags = htonl(cap->flags);
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}
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static void network_to_caps(RDMACapabilities *cap)
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{
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cap->version = ntohl(cap->version);
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cap->flags = ntohl(cap->flags);
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}
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/*
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* Representation of a RAMBlock from an RDMA perspective.
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* This is not transmitted, only local.
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* This and subsequent structures cannot be linked lists
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* because we're using a single IB message to transmit
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* the information. It's small anyway, so a list is overkill.
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*/
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typedef struct RDMALocalBlock {
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uint8_t *local_host_addr; /* local virtual address */
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uint64_t remote_host_addr; /* remote virtual address */
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uint64_t offset;
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uint64_t length;
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struct ibv_mr **pmr; /* MRs for chunk-level registration */
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struct ibv_mr *mr; /* MR for non-chunk-level registration */
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uint32_t *remote_keys; /* rkeys for chunk-level registration */
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uint32_t remote_rkey; /* rkeys for non-chunk-level registration */
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int index; /* which block are we */
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bool is_ram_block;
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int nb_chunks;
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unsigned long *transit_bitmap;
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unsigned long *unregister_bitmap;
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} RDMALocalBlock;
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/*
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* Also represents a RAMblock, but only on the dest.
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* This gets transmitted by the dest during connection-time
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* to the source VM and then is used to populate the
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* corresponding RDMALocalBlock with
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* the information needed to perform the actual RDMA.
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*/
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typedef struct QEMU_PACKED RDMARemoteBlock {
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uint64_t remote_host_addr;
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uint64_t offset;
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uint64_t length;
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uint32_t remote_rkey;
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uint32_t padding;
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} RDMARemoteBlock;
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static uint64_t htonll(uint64_t v)
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{
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union { uint32_t lv[2]; uint64_t llv; } u;
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u.lv[0] = htonl(v >> 32);
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u.lv[1] = htonl(v & 0xFFFFFFFFULL);
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return u.llv;
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}
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static uint64_t ntohll(uint64_t v) {
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union { uint32_t lv[2]; uint64_t llv; } u;
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u.llv = v;
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return ((uint64_t)ntohl(u.lv[0]) << 32) | (uint64_t) ntohl(u.lv[1]);
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}
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static void remote_block_to_network(RDMARemoteBlock *rb)
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{
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rb->remote_host_addr = htonll(rb->remote_host_addr);
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rb->offset = htonll(rb->offset);
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rb->length = htonll(rb->length);
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rb->remote_rkey = htonl(rb->remote_rkey);
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}
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static void network_to_remote_block(RDMARemoteBlock *rb)
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{
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rb->remote_host_addr = ntohll(rb->remote_host_addr);
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rb->offset = ntohll(rb->offset);
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rb->length = ntohll(rb->length);
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rb->remote_rkey = ntohl(rb->remote_rkey);
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}
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/*
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* Virtual address of the above structures used for transmitting
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* the RAMBlock descriptions at connection-time.
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* This structure is *not* transmitted.
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*/
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typedef struct RDMALocalBlocks {
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int nb_blocks;
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bool init; /* main memory init complete */
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RDMALocalBlock *block;
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} RDMALocalBlocks;
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/*
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* Main data structure for RDMA state.
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* While there is only one copy of this structure being allocated right now,
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* this is the place where one would start if you wanted to consider
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* having more than one RDMA connection open at the same time.
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*/
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typedef struct RDMAContext {
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char *host;
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int port;
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RDMAWorkRequestData wr_data[RDMA_WRID_MAX];
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/*
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* This is used by *_exchange_send() to figure out whether or not
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* the initial "READY" message has already been received or not.
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* This is because other functions may potentially poll() and detect
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* the READY message before send() does, in which case we need to
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* know if it completed.
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*/
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int control_ready_expected;
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/* number of outstanding writes */
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int nb_sent;
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/* store info about current buffer so that we can
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merge it with future sends */
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uint64_t current_addr;
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uint64_t current_length;
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/* index of ram block the current buffer belongs to */
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int current_index;
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/* index of the chunk in the current ram block */
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int current_chunk;
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bool pin_all;
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/*
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* infiniband-specific variables for opening the device
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* and maintaining connection state and so forth.
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*
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* cm_id also has ibv_context, rdma_event_channel, and ibv_qp in
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* cm_id->verbs, cm_id->channel, and cm_id->qp.
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*/
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struct rdma_cm_id *cm_id; /* connection manager ID */
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struct rdma_cm_id *listen_id;
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bool connected;
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struct ibv_context *verbs;
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struct rdma_event_channel *channel;
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struct ibv_qp *qp; /* queue pair */
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struct ibv_comp_channel *comp_channel; /* completion channel */
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struct ibv_pd *pd; /* protection domain */
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struct ibv_cq *cq; /* completion queue */
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/*
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* If a previous write failed (perhaps because of a failed
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* memory registration, then do not attempt any future work
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* and remember the error state.
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*/
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int error_state;
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int error_reported;
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/*
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* Description of ram blocks used throughout the code.
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*/
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RDMALocalBlocks local_ram_blocks;
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RDMARemoteBlock *block;
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/*
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* Migration on *destination* started.
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* Then use coroutine yield function.
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* Source runs in a thread, so we don't care.
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*/
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int migration_started_on_destination;
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int total_registrations;
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int total_writes;
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int unregister_current, unregister_next;
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uint64_t unregistrations[RDMA_SIGNALED_SEND_MAX];
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GHashTable *blockmap;
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} RDMAContext;
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/*
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* Interface to the rest of the migration call stack.
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*/
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typedef struct QEMUFileRDMA {
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RDMAContext *rdma;
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size_t len;
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void *file;
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} QEMUFileRDMA;
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/*
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* Main structure for IB Send/Recv control messages.
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* This gets prepended at the beginning of every Send/Recv.
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*/
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typedef struct QEMU_PACKED {
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uint32_t len; /* Total length of data portion */
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uint32_t type; /* which control command to perform */
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uint32_t repeat; /* number of commands in data portion of same type */
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uint32_t padding;
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} RDMAControlHeader;
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static void control_to_network(RDMAControlHeader *control)
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{
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control->type = htonl(control->type);
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control->len = htonl(control->len);
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control->repeat = htonl(control->repeat);
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}
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static void network_to_control(RDMAControlHeader *control)
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{
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control->type = ntohl(control->type);
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control->len = ntohl(control->len);
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control->repeat = ntohl(control->repeat);
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}
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/*
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* Register a single Chunk.
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* Information sent by the source VM to inform the dest
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* to register an single chunk of memory before we can perform
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* the actual RDMA operation.
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*/
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typedef struct QEMU_PACKED {
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union QEMU_PACKED {
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uint64_t current_addr; /* offset into the ramblock of the chunk */
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uint64_t chunk; /* chunk to lookup if unregistering */
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} key;
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uint32_t current_index; /* which ramblock the chunk belongs to */
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uint32_t padding;
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uint64_t chunks; /* how many sequential chunks to register */
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} RDMARegister;
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static void register_to_network(RDMARegister *reg)
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{
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reg->key.current_addr = htonll(reg->key.current_addr);
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reg->current_index = htonl(reg->current_index);
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reg->chunks = htonll(reg->chunks);
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}
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static void network_to_register(RDMARegister *reg)
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{
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reg->key.current_addr = ntohll(reg->key.current_addr);
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reg->current_index = ntohl(reg->current_index);
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reg->chunks = ntohll(reg->chunks);
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}
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typedef struct QEMU_PACKED {
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uint32_t value; /* if zero, we will madvise() */
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uint32_t block_idx; /* which ram block index */
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uint64_t offset; /* where in the remote ramblock this chunk */
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uint64_t length; /* length of the chunk */
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} RDMACompress;
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static void compress_to_network(RDMACompress *comp)
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{
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comp->value = htonl(comp->value);
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comp->block_idx = htonl(comp->block_idx);
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comp->offset = htonll(comp->offset);
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comp->length = htonll(comp->length);
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}
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static void network_to_compress(RDMACompress *comp)
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{
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comp->value = ntohl(comp->value);
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comp->block_idx = ntohl(comp->block_idx);
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comp->offset = ntohll(comp->offset);
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comp->length = ntohll(comp->length);
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}
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/*
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* The result of the dest's memory registration produces an "rkey"
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* which the source VM must reference in order to perform
|
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* the RDMA operation.
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*/
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typedef struct QEMU_PACKED {
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uint32_t rkey;
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uint32_t padding;
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uint64_t host_addr;
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} RDMARegisterResult;
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static void result_to_network(RDMARegisterResult *result)
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{
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result->rkey = htonl(result->rkey);
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result->host_addr = htonll(result->host_addr);
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};
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static void network_to_result(RDMARegisterResult *result)
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{
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result->rkey = ntohl(result->rkey);
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result->host_addr = ntohll(result->host_addr);
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};
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const char *print_wrid(int wrid);
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static int qemu_rdma_exchange_send(RDMAContext *rdma, RDMAControlHeader *head,
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uint8_t *data, RDMAControlHeader *resp,
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int *resp_idx,
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int (*callback)(RDMAContext *rdma));
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static inline uint64_t ram_chunk_index(const uint8_t *start,
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const uint8_t *host)
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{
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return ((uintptr_t) host - (uintptr_t) start) >> RDMA_REG_CHUNK_SHIFT;
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}
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static inline uint8_t *ram_chunk_start(const RDMALocalBlock *rdma_ram_block,
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uint64_t i)
|
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{
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return (uint8_t *)(uintptr_t)(rdma_ram_block->local_host_addr +
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(i << RDMA_REG_CHUNK_SHIFT));
|
|
}
|
|
|
|
static inline uint8_t *ram_chunk_end(const RDMALocalBlock *rdma_ram_block,
|
|
uint64_t i)
|
|
{
|
|
uint8_t *result = ram_chunk_start(rdma_ram_block, i) +
|
|
(1UL << RDMA_REG_CHUNK_SHIFT);
|
|
|
|
if (result > (rdma_ram_block->local_host_addr + rdma_ram_block->length)) {
|
|
result = rdma_ram_block->local_host_addr + rdma_ram_block->length;
|
|
}
|
|
|
|
return result;
|
|
}
|
|
|
|
static int rdma_add_block(RDMAContext *rdma, void *host_addr,
|
|
ram_addr_t block_offset, uint64_t length)
|
|
{
|
|
RDMALocalBlocks *local = &rdma->local_ram_blocks;
|
|
RDMALocalBlock *block = g_hash_table_lookup(rdma->blockmap,
|
|
(void *)(uintptr_t)block_offset);
|
|
RDMALocalBlock *old = local->block;
|
|
|
|
assert(block == NULL);
|
|
|
|
local->block = g_malloc0(sizeof(RDMALocalBlock) * (local->nb_blocks + 1));
|
|
|
|
if (local->nb_blocks) {
|
|
int x;
|
|
|
|
for (x = 0; x < local->nb_blocks; x++) {
|
|
g_hash_table_remove(rdma->blockmap,
|
|
(void *)(uintptr_t)old[x].offset);
|
|
g_hash_table_insert(rdma->blockmap,
|
|
(void *)(uintptr_t)old[x].offset,
|
|
&local->block[x]);
|
|
}
|
|
memcpy(local->block, old, sizeof(RDMALocalBlock) * local->nb_blocks);
|
|
g_free(old);
|
|
}
|
|
|
|
block = &local->block[local->nb_blocks];
|
|
|
|
block->local_host_addr = host_addr;
|
|
block->offset = block_offset;
|
|
block->length = length;
|
|
block->index = local->nb_blocks;
|
|
block->nb_chunks = ram_chunk_index(host_addr, host_addr + length) + 1UL;
|
|
block->transit_bitmap = bitmap_new(block->nb_chunks);
|
|
bitmap_clear(block->transit_bitmap, 0, block->nb_chunks);
|
|
block->unregister_bitmap = bitmap_new(block->nb_chunks);
|
|
bitmap_clear(block->unregister_bitmap, 0, block->nb_chunks);
|
|
block->remote_keys = g_malloc0(block->nb_chunks * sizeof(uint32_t));
|
|
|
|
block->is_ram_block = local->init ? false : true;
|
|
|
|
g_hash_table_insert(rdma->blockmap, (void *) block_offset, block);
|
|
|
|
trace_rdma_add_block(local->nb_blocks, (uintptr_t) block->local_host_addr,
|
|
block->offset, block->length,
|
|
(uintptr_t) (block->local_host_addr + block->length),
|
|
BITS_TO_LONGS(block->nb_chunks) *
|
|
sizeof(unsigned long) * 8,
|
|
block->nb_chunks);
|
|
|
|
local->nb_blocks++;
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Memory regions need to be registered with the device and queue pairs setup
|
|
* in advanced before the migration starts. This tells us where the RAM blocks
|
|
* are so that we can register them individually.
|
|
*/
|
|
static void qemu_rdma_init_one_block(void *host_addr,
|
|
ram_addr_t block_offset, ram_addr_t length, void *opaque)
|
|
{
|
|
rdma_add_block(opaque, host_addr, block_offset, length);
|
|
}
|
|
|
|
/*
|
|
* Identify the RAMBlocks and their quantity. They will be references to
|
|
* identify chunk boundaries inside each RAMBlock and also be referenced
|
|
* during dynamic page registration.
|
|
*/
|
|
static int qemu_rdma_init_ram_blocks(RDMAContext *rdma)
|
|
{
|
|
RDMALocalBlocks *local = &rdma->local_ram_blocks;
|
|
|
|
assert(rdma->blockmap == NULL);
|
|
rdma->blockmap = g_hash_table_new(g_direct_hash, g_direct_equal);
|
|
memset(local, 0, sizeof *local);
|
|
qemu_ram_foreach_block(qemu_rdma_init_one_block, rdma);
|
|
trace_qemu_rdma_init_ram_blocks(local->nb_blocks);
|
|
rdma->block = (RDMARemoteBlock *) g_malloc0(sizeof(RDMARemoteBlock) *
|
|
rdma->local_ram_blocks.nb_blocks);
|
|
local->init = true;
|
|
return 0;
|
|
}
|
|
|
|
static int rdma_delete_block(RDMAContext *rdma, ram_addr_t block_offset)
|
|
{
|
|
RDMALocalBlocks *local = &rdma->local_ram_blocks;
|
|
RDMALocalBlock *block = g_hash_table_lookup(rdma->blockmap,
|
|
(void *) block_offset);
|
|
RDMALocalBlock *old = local->block;
|
|
int x;
|
|
|
|
assert(block);
|
|
|
|
if (block->pmr) {
|
|
int j;
|
|
|
|
for (j = 0; j < block->nb_chunks; j++) {
|
|
if (!block->pmr[j]) {
|
|
continue;
|
|
}
|
|
ibv_dereg_mr(block->pmr[j]);
|
|
rdma->total_registrations--;
|
|
}
|
|
g_free(block->pmr);
|
|
block->pmr = NULL;
|
|
}
|
|
|
|
if (block->mr) {
|
|
ibv_dereg_mr(block->mr);
|
|
rdma->total_registrations--;
|
|
block->mr = NULL;
|
|
}
|
|
|
|
g_free(block->transit_bitmap);
|
|
block->transit_bitmap = NULL;
|
|
|
|
g_free(block->unregister_bitmap);
|
|
block->unregister_bitmap = NULL;
|
|
|
|
g_free(block->remote_keys);
|
|
block->remote_keys = NULL;
|
|
|
|
for (x = 0; x < local->nb_blocks; x++) {
|
|
g_hash_table_remove(rdma->blockmap, (void *)(uintptr_t)old[x].offset);
|
|
}
|
|
|
|
if (local->nb_blocks > 1) {
|
|
|
|
local->block = g_malloc0(sizeof(RDMALocalBlock) *
|
|
(local->nb_blocks - 1));
|
|
|
|
if (block->index) {
|
|
memcpy(local->block, old, sizeof(RDMALocalBlock) * block->index);
|
|
}
|
|
|
|
if (block->index < (local->nb_blocks - 1)) {
|
|
memcpy(local->block + block->index, old + (block->index + 1),
|
|
sizeof(RDMALocalBlock) *
|
|
(local->nb_blocks - (block->index + 1)));
|
|
}
|
|
} else {
|
|
assert(block == local->block);
|
|
local->block = NULL;
|
|
}
|
|
|
|
trace_rdma_delete_block(local->nb_blocks,
|
|
(uintptr_t)block->local_host_addr,
|
|
block->offset, block->length,
|
|
(uintptr_t)(block->local_host_addr + block->length),
|
|
BITS_TO_LONGS(block->nb_chunks) *
|
|
sizeof(unsigned long) * 8, block->nb_chunks);
|
|
|
|
g_free(old);
|
|
|
|
local->nb_blocks--;
|
|
|
|
if (local->nb_blocks) {
|
|
for (x = 0; x < local->nb_blocks; x++) {
|
|
g_hash_table_insert(rdma->blockmap,
|
|
(void *)(uintptr_t)local->block[x].offset,
|
|
&local->block[x]);
|
|
}
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Put in the log file which RDMA device was opened and the details
|
|
* associated with that device.
|
|
*/
|
|
static void qemu_rdma_dump_id(const char *who, struct ibv_context *verbs)
|
|
{
|
|
struct ibv_port_attr port;
|
|
|
|
if (ibv_query_port(verbs, 1, &port)) {
|
|
error_report("Failed to query port information");
|
|
return;
|
|
}
|
|
|
|
printf("%s RDMA Device opened: kernel name %s "
|
|
"uverbs device name %s, "
|
|
"infiniband_verbs class device path %s, "
|
|
"infiniband class device path %s, "
|
|
"transport: (%d) %s\n",
|
|
who,
|
|
verbs->device->name,
|
|
verbs->device->dev_name,
|
|
verbs->device->dev_path,
|
|
verbs->device->ibdev_path,
|
|
port.link_layer,
|
|
(port.link_layer == IBV_LINK_LAYER_INFINIBAND) ? "Infiniband" :
|
|
((port.link_layer == IBV_LINK_LAYER_ETHERNET)
|
|
? "Ethernet" : "Unknown"));
|
|
}
|
|
|
|
/*
|
|
* Put in the log file the RDMA gid addressing information,
|
|
* useful for folks who have trouble understanding the
|
|
* RDMA device hierarchy in the kernel.
|
|
*/
|
|
static void qemu_rdma_dump_gid(const char *who, struct rdma_cm_id *id)
|
|
{
|
|
char sgid[33];
|
|
char dgid[33];
|
|
inet_ntop(AF_INET6, &id->route.addr.addr.ibaddr.sgid, sgid, sizeof sgid);
|
|
inet_ntop(AF_INET6, &id->route.addr.addr.ibaddr.dgid, dgid, sizeof dgid);
|
|
trace_qemu_rdma_dump_gid(who, sgid, dgid);
|
|
}
|
|
|
|
/*
|
|
* As of now, IPv6 over RoCE / iWARP is not supported by linux.
|
|
* We will try the next addrinfo struct, and fail if there are
|
|
* no other valid addresses to bind against.
|
|
*
|
|
* If user is listening on '[::]', then we will not have a opened a device
|
|
* yet and have no way of verifying if the device is RoCE or not.
|
|
*
|
|
* In this case, the source VM will throw an error for ALL types of
|
|
* connections (both IPv4 and IPv6) if the destination machine does not have
|
|
* a regular infiniband network available for use.
|
|
*
|
|
* The only way to guarantee that an error is thrown for broken kernels is
|
|
* for the management software to choose a *specific* interface at bind time
|
|
* and validate what time of hardware it is.
|
|
*
|
|
* Unfortunately, this puts the user in a fix:
|
|
*
|
|
* If the source VM connects with an IPv4 address without knowing that the
|
|
* destination has bound to '[::]' the migration will unconditionally fail
|
|
* unless the management software is explicitly listening on the the IPv4
|
|
* address while using a RoCE-based device.
|
|
*
|
|
* If the source VM connects with an IPv6 address, then we're OK because we can
|
|
* throw an error on the source (and similarly on the destination).
|
|
*
|
|
* But in mixed environments, this will be broken for a while until it is fixed
|
|
* inside linux.
|
|
*
|
|
* We do provide a *tiny* bit of help in this function: We can list all of the
|
|
* devices in the system and check to see if all the devices are RoCE or
|
|
* Infiniband.
|
|
*
|
|
* If we detect that we have a *pure* RoCE environment, then we can safely
|
|
* thrown an error even if the management software has specified '[::]' as the
|
|
* bind address.
|
|
*
|
|
* However, if there is are multiple hetergeneous devices, then we cannot make
|
|
* this assumption and the user just has to be sure they know what they are
|
|
* doing.
|
|
*
|
|
* Patches are being reviewed on linux-rdma.
|
|
*/
|
|
static int qemu_rdma_broken_ipv6_kernel(Error **errp, struct ibv_context *verbs)
|
|
{
|
|
struct ibv_port_attr port_attr;
|
|
|
|
/* This bug only exists in linux, to our knowledge. */
|
|
#ifdef CONFIG_LINUX
|
|
|
|
/*
|
|
* Verbs are only NULL if management has bound to '[::]'.
|
|
*
|
|
* Let's iterate through all the devices and see if there any pure IB
|
|
* devices (non-ethernet).
|
|
*
|
|
* If not, then we can safely proceed with the migration.
|
|
* Otherwise, there are no guarantees until the bug is fixed in linux.
|
|
*/
|
|
if (!verbs) {
|
|
int num_devices, x;
|
|
struct ibv_device ** dev_list = ibv_get_device_list(&num_devices);
|
|
bool roce_found = false;
|
|
bool ib_found = false;
|
|
|
|
for (x = 0; x < num_devices; x++) {
|
|
verbs = ibv_open_device(dev_list[x]);
|
|
|
|
if (ibv_query_port(verbs, 1, &port_attr)) {
|
|
ibv_close_device(verbs);
|
|
ERROR(errp, "Could not query initial IB port");
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (port_attr.link_layer == IBV_LINK_LAYER_INFINIBAND) {
|
|
ib_found = true;
|
|
} else if (port_attr.link_layer == IBV_LINK_LAYER_ETHERNET) {
|
|
roce_found = true;
|
|
}
|
|
|
|
ibv_close_device(verbs);
|
|
|
|
}
|
|
|
|
if (roce_found) {
|
|
if (ib_found) {
|
|
fprintf(stderr, "WARN: migrations may fail:"
|
|
" IPv6 over RoCE / iWARP in linux"
|
|
" is broken. But since you appear to have a"
|
|
" mixed RoCE / IB environment, be sure to only"
|
|
" migrate over the IB fabric until the kernel "
|
|
" fixes the bug.\n");
|
|
} else {
|
|
ERROR(errp, "You only have RoCE / iWARP devices in your systems"
|
|
" and your management software has specified '[::]'"
|
|
", but IPv6 over RoCE / iWARP is not supported in Linux.");
|
|
return -ENONET;
|
|
}
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* If we have a verbs context, that means that some other than '[::]' was
|
|
* used by the management software for binding. In which case we can
|
|
* actually warn the user about a potentially broken kernel.
|
|
*/
|
|
|
|
/* IB ports start with 1, not 0 */
|
|
if (ibv_query_port(verbs, 1, &port_attr)) {
|
|
ERROR(errp, "Could not query initial IB port");
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (port_attr.link_layer == IBV_LINK_LAYER_ETHERNET) {
|
|
ERROR(errp, "Linux kernel's RoCE / iWARP does not support IPv6 "
|
|
"(but patches on linux-rdma in progress)");
|
|
return -ENONET;
|
|
}
|
|
|
|
#endif
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Figure out which RDMA device corresponds to the requested IP hostname
|
|
* Also create the initial connection manager identifiers for opening
|
|
* the connection.
|
|
*/
|
|
static int qemu_rdma_resolve_host(RDMAContext *rdma, Error **errp)
|
|
{
|
|
int ret;
|
|
struct rdma_addrinfo *res;
|
|
char port_str[16];
|
|
struct rdma_cm_event *cm_event;
|
|
char ip[40] = "unknown";
|
|
struct rdma_addrinfo *e;
|
|
|
|
if (rdma->host == NULL || !strcmp(rdma->host, "")) {
|
|
ERROR(errp, "RDMA hostname has not been set");
|
|
return -EINVAL;
|
|
}
|
|
|
|
/* create CM channel */
|
|
rdma->channel = rdma_create_event_channel();
|
|
if (!rdma->channel) {
|
|
ERROR(errp, "could not create CM channel");
|
|
return -EINVAL;
|
|
}
|
|
|
|
/* create CM id */
|
|
ret = rdma_create_id(rdma->channel, &rdma->cm_id, NULL, RDMA_PS_TCP);
|
|
if (ret) {
|
|
ERROR(errp, "could not create channel id");
|
|
goto err_resolve_create_id;
|
|
}
|
|
|
|
snprintf(port_str, 16, "%d", rdma->port);
|
|
port_str[15] = '\0';
|
|
|
|
ret = rdma_getaddrinfo(rdma->host, port_str, NULL, &res);
|
|
if (ret < 0) {
|
|
ERROR(errp, "could not rdma_getaddrinfo address %s", rdma->host);
|
|
goto err_resolve_get_addr;
|
|
}
|
|
|
|
for (e = res; e != NULL; e = e->ai_next) {
|
|
inet_ntop(e->ai_family,
|
|
&((struct sockaddr_in *) e->ai_dst_addr)->sin_addr, ip, sizeof ip);
|
|
trace_qemu_rdma_resolve_host_trying(rdma->host, ip);
|
|
|
|
ret = rdma_resolve_addr(rdma->cm_id, NULL, e->ai_dst_addr,
|
|
RDMA_RESOLVE_TIMEOUT_MS);
|
|
if (!ret) {
|
|
if (e->ai_family == AF_INET6) {
|
|
ret = qemu_rdma_broken_ipv6_kernel(errp, rdma->cm_id->verbs);
|
|
if (ret) {
|
|
continue;
|
|
}
|
|
}
|
|
goto route;
|
|
}
|
|
}
|
|
|
|
ERROR(errp, "could not resolve address %s", rdma->host);
|
|
goto err_resolve_get_addr;
|
|
|
|
route:
|
|
qemu_rdma_dump_gid("source_resolve_addr", rdma->cm_id);
|
|
|
|
ret = rdma_get_cm_event(rdma->channel, &cm_event);
|
|
if (ret) {
|
|
ERROR(errp, "could not perform event_addr_resolved");
|
|
goto err_resolve_get_addr;
|
|
}
|
|
|
|
if (cm_event->event != RDMA_CM_EVENT_ADDR_RESOLVED) {
|
|
ERROR(errp, "result not equal to event_addr_resolved %s",
|
|
rdma_event_str(cm_event->event));
|
|
perror("rdma_resolve_addr");
|
|
rdma_ack_cm_event(cm_event);
|
|
ret = -EINVAL;
|
|
goto err_resolve_get_addr;
|
|
}
|
|
rdma_ack_cm_event(cm_event);
|
|
|
|
/* resolve route */
|
|
ret = rdma_resolve_route(rdma->cm_id, RDMA_RESOLVE_TIMEOUT_MS);
|
|
if (ret) {
|
|
ERROR(errp, "could not resolve rdma route");
|
|
goto err_resolve_get_addr;
|
|
}
|
|
|
|
ret = rdma_get_cm_event(rdma->channel, &cm_event);
|
|
if (ret) {
|
|
ERROR(errp, "could not perform event_route_resolved");
|
|
goto err_resolve_get_addr;
|
|
}
|
|
if (cm_event->event != RDMA_CM_EVENT_ROUTE_RESOLVED) {
|
|
ERROR(errp, "result not equal to event_route_resolved: %s",
|
|
rdma_event_str(cm_event->event));
|
|
rdma_ack_cm_event(cm_event);
|
|
ret = -EINVAL;
|
|
goto err_resolve_get_addr;
|
|
}
|
|
rdma_ack_cm_event(cm_event);
|
|
rdma->verbs = rdma->cm_id->verbs;
|
|
qemu_rdma_dump_id("source_resolve_host", rdma->cm_id->verbs);
|
|
qemu_rdma_dump_gid("source_resolve_host", rdma->cm_id);
|
|
return 0;
|
|
|
|
err_resolve_get_addr:
|
|
rdma_destroy_id(rdma->cm_id);
|
|
rdma->cm_id = NULL;
|
|
err_resolve_create_id:
|
|
rdma_destroy_event_channel(rdma->channel);
|
|
rdma->channel = NULL;
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* Create protection domain and completion queues
|
|
*/
|
|
static int qemu_rdma_alloc_pd_cq(RDMAContext *rdma)
|
|
{
|
|
/* allocate pd */
|
|
rdma->pd = ibv_alloc_pd(rdma->verbs);
|
|
if (!rdma->pd) {
|
|
error_report("failed to allocate protection domain");
|
|
return -1;
|
|
}
|
|
|
|
/* create completion channel */
|
|
rdma->comp_channel = ibv_create_comp_channel(rdma->verbs);
|
|
if (!rdma->comp_channel) {
|
|
error_report("failed to allocate completion channel");
|
|
goto err_alloc_pd_cq;
|
|
}
|
|
|
|
/*
|
|
* Completion queue can be filled by both read and write work requests,
|
|
* so must reflect the sum of both possible queue sizes.
|
|
*/
|
|
rdma->cq = ibv_create_cq(rdma->verbs, (RDMA_SIGNALED_SEND_MAX * 3),
|
|
NULL, rdma->comp_channel, 0);
|
|
if (!rdma->cq) {
|
|
error_report("failed to allocate completion queue");
|
|
goto err_alloc_pd_cq;
|
|
}
|
|
|
|
return 0;
|
|
|
|
err_alloc_pd_cq:
|
|
if (rdma->pd) {
|
|
ibv_dealloc_pd(rdma->pd);
|
|
}
|
|
if (rdma->comp_channel) {
|
|
ibv_destroy_comp_channel(rdma->comp_channel);
|
|
}
|
|
rdma->pd = NULL;
|
|
rdma->comp_channel = NULL;
|
|
return -1;
|
|
|
|
}
|
|
|
|
/*
|
|
* Create queue pairs.
|
|
*/
|
|
static int qemu_rdma_alloc_qp(RDMAContext *rdma)
|
|
{
|
|
struct ibv_qp_init_attr attr = { 0 };
|
|
int ret;
|
|
|
|
attr.cap.max_send_wr = RDMA_SIGNALED_SEND_MAX;
|
|
attr.cap.max_recv_wr = 3;
|
|
attr.cap.max_send_sge = 1;
|
|
attr.cap.max_recv_sge = 1;
|
|
attr.send_cq = rdma->cq;
|
|
attr.recv_cq = rdma->cq;
|
|
attr.qp_type = IBV_QPT_RC;
|
|
|
|
ret = rdma_create_qp(rdma->cm_id, rdma->pd, &attr);
|
|
if (ret) {
|
|
return -1;
|
|
}
|
|
|
|
rdma->qp = rdma->cm_id->qp;
|
|
return 0;
|
|
}
|
|
|
|
static int qemu_rdma_reg_whole_ram_blocks(RDMAContext *rdma)
|
|
{
|
|
int i;
|
|
RDMALocalBlocks *local = &rdma->local_ram_blocks;
|
|
|
|
for (i = 0; i < local->nb_blocks; i++) {
|
|
local->block[i].mr =
|
|
ibv_reg_mr(rdma->pd,
|
|
local->block[i].local_host_addr,
|
|
local->block[i].length,
|
|
IBV_ACCESS_LOCAL_WRITE |
|
|
IBV_ACCESS_REMOTE_WRITE
|
|
);
|
|
if (!local->block[i].mr) {
|
|
perror("Failed to register local dest ram block!\n");
|
|
break;
|
|
}
|
|
rdma->total_registrations++;
|
|
}
|
|
|
|
if (i >= local->nb_blocks) {
|
|
return 0;
|
|
}
|
|
|
|
for (i--; i >= 0; i--) {
|
|
ibv_dereg_mr(local->block[i].mr);
|
|
rdma->total_registrations--;
|
|
}
|
|
|
|
return -1;
|
|
|
|
}
|
|
|
|
/*
|
|
* Find the ram block that corresponds to the page requested to be
|
|
* transmitted by QEMU.
|
|
*
|
|
* Once the block is found, also identify which 'chunk' within that
|
|
* block that the page belongs to.
|
|
*
|
|
* This search cannot fail or the migration will fail.
|
|
*/
|
|
static int qemu_rdma_search_ram_block(RDMAContext *rdma,
|
|
uintptr_t block_offset,
|
|
uint64_t offset,
|
|
uint64_t length,
|
|
uint64_t *block_index,
|
|
uint64_t *chunk_index)
|
|
{
|
|
uint64_t current_addr = block_offset + offset;
|
|
RDMALocalBlock *block = g_hash_table_lookup(rdma->blockmap,
|
|
(void *) block_offset);
|
|
assert(block);
|
|
assert(current_addr >= block->offset);
|
|
assert((current_addr + length) <= (block->offset + block->length));
|
|
|
|
*block_index = block->index;
|
|
*chunk_index = ram_chunk_index(block->local_host_addr,
|
|
block->local_host_addr + (current_addr - block->offset));
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Register a chunk with IB. If the chunk was already registered
|
|
* previously, then skip.
|
|
*
|
|
* Also return the keys associated with the registration needed
|
|
* to perform the actual RDMA operation.
|
|
*/
|
|
static int qemu_rdma_register_and_get_keys(RDMAContext *rdma,
|
|
RDMALocalBlock *block, uintptr_t host_addr,
|
|
uint32_t *lkey, uint32_t *rkey, int chunk,
|
|
uint8_t *chunk_start, uint8_t *chunk_end)
|
|
{
|
|
if (block->mr) {
|
|
if (lkey) {
|
|
*lkey = block->mr->lkey;
|
|
}
|
|
if (rkey) {
|
|
*rkey = block->mr->rkey;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
/* allocate memory to store chunk MRs */
|
|
if (!block->pmr) {
|
|
block->pmr = g_malloc0(block->nb_chunks * sizeof(struct ibv_mr *));
|
|
}
|
|
|
|
/*
|
|
* If 'rkey', then we're the destination, so grant access to the source.
|
|
*
|
|
* If 'lkey', then we're the source VM, so grant access only to ourselves.
|
|
*/
|
|
if (!block->pmr[chunk]) {
|
|
uint64_t len = chunk_end - chunk_start;
|
|
|
|
trace_qemu_rdma_register_and_get_keys(len, chunk_start);
|
|
|
|
block->pmr[chunk] = ibv_reg_mr(rdma->pd,
|
|
chunk_start, len,
|
|
(rkey ? (IBV_ACCESS_LOCAL_WRITE |
|
|
IBV_ACCESS_REMOTE_WRITE) : 0));
|
|
|
|
if (!block->pmr[chunk]) {
|
|
perror("Failed to register chunk!");
|
|
fprintf(stderr, "Chunk details: block: %d chunk index %d"
|
|
" start %" PRIuPTR " end %" PRIuPTR
|
|
" host %" PRIuPTR
|
|
" local %" PRIuPTR " registrations: %d\n",
|
|
block->index, chunk, (uintptr_t)chunk_start,
|
|
(uintptr_t)chunk_end, host_addr,
|
|
(uintptr_t)block->local_host_addr,
|
|
rdma->total_registrations);
|
|
return -1;
|
|
}
|
|
rdma->total_registrations++;
|
|
}
|
|
|
|
if (lkey) {
|
|
*lkey = block->pmr[chunk]->lkey;
|
|
}
|
|
if (rkey) {
|
|
*rkey = block->pmr[chunk]->rkey;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Register (at connection time) the memory used for control
|
|
* channel messages.
|
|
*/
|
|
static int qemu_rdma_reg_control(RDMAContext *rdma, int idx)
|
|
{
|
|
rdma->wr_data[idx].control_mr = ibv_reg_mr(rdma->pd,
|
|
rdma->wr_data[idx].control, RDMA_CONTROL_MAX_BUFFER,
|
|
IBV_ACCESS_LOCAL_WRITE | IBV_ACCESS_REMOTE_WRITE);
|
|
if (rdma->wr_data[idx].control_mr) {
|
|
rdma->total_registrations++;
|
|
return 0;
|
|
}
|
|
error_report("qemu_rdma_reg_control failed");
|
|
return -1;
|
|
}
|
|
|
|
const char *print_wrid(int wrid)
|
|
{
|
|
if (wrid >= RDMA_WRID_RECV_CONTROL) {
|
|
return wrid_desc[RDMA_WRID_RECV_CONTROL];
|
|
}
|
|
return wrid_desc[wrid];
|
|
}
|
|
|
|
/*
|
|
* RDMA requires memory registration (mlock/pinning), but this is not good for
|
|
* overcommitment.
|
|
*
|
|
* In preparation for the future where LRU information or workload-specific
|
|
* writable writable working set memory access behavior is available to QEMU
|
|
* it would be nice to have in place the ability to UN-register/UN-pin
|
|
* particular memory regions from the RDMA hardware when it is determine that
|
|
* those regions of memory will likely not be accessed again in the near future.
|
|
*
|
|
* While we do not yet have such information right now, the following
|
|
* compile-time option allows us to perform a non-optimized version of this
|
|
* behavior.
|
|
*
|
|
* By uncommenting this option, you will cause *all* RDMA transfers to be
|
|
* unregistered immediately after the transfer completes on both sides of the
|
|
* connection. This has no effect in 'rdma-pin-all' mode, only regular mode.
|
|
*
|
|
* This will have a terrible impact on migration performance, so until future
|
|
* workload information or LRU information is available, do not attempt to use
|
|
* this feature except for basic testing.
|
|
*/
|
|
//#define RDMA_UNREGISTRATION_EXAMPLE
|
|
|
|
/*
|
|
* Perform a non-optimized memory unregistration after every transfer
|
|
* for demonsration purposes, only if pin-all is not requested.
|
|
*
|
|
* Potential optimizations:
|
|
* 1. Start a new thread to run this function continuously
|
|
- for bit clearing
|
|
- and for receipt of unregister messages
|
|
* 2. Use an LRU.
|
|
* 3. Use workload hints.
|
|
*/
|
|
static int qemu_rdma_unregister_waiting(RDMAContext *rdma)
|
|
{
|
|
while (rdma->unregistrations[rdma->unregister_current]) {
|
|
int ret;
|
|
uint64_t wr_id = rdma->unregistrations[rdma->unregister_current];
|
|
uint64_t chunk =
|
|
(wr_id & RDMA_WRID_CHUNK_MASK) >> RDMA_WRID_CHUNK_SHIFT;
|
|
uint64_t index =
|
|
(wr_id & RDMA_WRID_BLOCK_MASK) >> RDMA_WRID_BLOCK_SHIFT;
|
|
RDMALocalBlock *block =
|
|
&(rdma->local_ram_blocks.block[index]);
|
|
RDMARegister reg = { .current_index = index };
|
|
RDMAControlHeader resp = { .type = RDMA_CONTROL_UNREGISTER_FINISHED,
|
|
};
|
|
RDMAControlHeader head = { .len = sizeof(RDMARegister),
|
|
.type = RDMA_CONTROL_UNREGISTER_REQUEST,
|
|
.repeat = 1,
|
|
};
|
|
|
|
trace_qemu_rdma_unregister_waiting_proc(chunk,
|
|
rdma->unregister_current);
|
|
|
|
rdma->unregistrations[rdma->unregister_current] = 0;
|
|
rdma->unregister_current++;
|
|
|
|
if (rdma->unregister_current == RDMA_SIGNALED_SEND_MAX) {
|
|
rdma->unregister_current = 0;
|
|
}
|
|
|
|
|
|
/*
|
|
* Unregistration is speculative (because migration is single-threaded
|
|
* and we cannot break the protocol's inifinband message ordering).
|
|
* Thus, if the memory is currently being used for transmission,
|
|
* then abort the attempt to unregister and try again
|
|
* later the next time a completion is received for this memory.
|
|
*/
|
|
clear_bit(chunk, block->unregister_bitmap);
|
|
|
|
if (test_bit(chunk, block->transit_bitmap)) {
|
|
trace_qemu_rdma_unregister_waiting_inflight(chunk);
|
|
continue;
|
|
}
|
|
|
|
trace_qemu_rdma_unregister_waiting_send(chunk);
|
|
|
|
ret = ibv_dereg_mr(block->pmr[chunk]);
|
|
block->pmr[chunk] = NULL;
|
|
block->remote_keys[chunk] = 0;
|
|
|
|
if (ret != 0) {
|
|
perror("unregistration chunk failed");
|
|
return -ret;
|
|
}
|
|
rdma->total_registrations--;
|
|
|
|
reg.key.chunk = chunk;
|
|
register_to_network(®);
|
|
ret = qemu_rdma_exchange_send(rdma, &head, (uint8_t *) ®,
|
|
&resp, NULL, NULL);
|
|
if (ret < 0) {
|
|
return ret;
|
|
}
|
|
|
|
trace_qemu_rdma_unregister_waiting_complete(chunk);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static uint64_t qemu_rdma_make_wrid(uint64_t wr_id, uint64_t index,
|
|
uint64_t chunk)
|
|
{
|
|
uint64_t result = wr_id & RDMA_WRID_TYPE_MASK;
|
|
|
|
result |= (index << RDMA_WRID_BLOCK_SHIFT);
|
|
result |= (chunk << RDMA_WRID_CHUNK_SHIFT);
|
|
|
|
return result;
|
|
}
|
|
|
|
/*
|
|
* Set bit for unregistration in the next iteration.
|
|
* We cannot transmit right here, but will unpin later.
|
|
*/
|
|
static void qemu_rdma_signal_unregister(RDMAContext *rdma, uint64_t index,
|
|
uint64_t chunk, uint64_t wr_id)
|
|
{
|
|
if (rdma->unregistrations[rdma->unregister_next] != 0) {
|
|
error_report("rdma migration: queue is full");
|
|
} else {
|
|
RDMALocalBlock *block = &(rdma->local_ram_blocks.block[index]);
|
|
|
|
if (!test_and_set_bit(chunk, block->unregister_bitmap)) {
|
|
trace_qemu_rdma_signal_unregister_append(chunk,
|
|
rdma->unregister_next);
|
|
|
|
rdma->unregistrations[rdma->unregister_next++] =
|
|
qemu_rdma_make_wrid(wr_id, index, chunk);
|
|
|
|
if (rdma->unregister_next == RDMA_SIGNALED_SEND_MAX) {
|
|
rdma->unregister_next = 0;
|
|
}
|
|
} else {
|
|
trace_qemu_rdma_signal_unregister_already(chunk);
|
|
}
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Consult the connection manager to see a work request
|
|
* (of any kind) has completed.
|
|
* Return the work request ID that completed.
|
|
*/
|
|
static uint64_t qemu_rdma_poll(RDMAContext *rdma, uint64_t *wr_id_out,
|
|
uint32_t *byte_len)
|
|
{
|
|
int ret;
|
|
struct ibv_wc wc;
|
|
uint64_t wr_id;
|
|
|
|
ret = ibv_poll_cq(rdma->cq, 1, &wc);
|
|
|
|
if (!ret) {
|
|
*wr_id_out = RDMA_WRID_NONE;
|
|
return 0;
|
|
}
|
|
|
|
if (ret < 0) {
|
|
error_report("ibv_poll_cq return %d", ret);
|
|
return ret;
|
|
}
|
|
|
|
wr_id = wc.wr_id & RDMA_WRID_TYPE_MASK;
|
|
|
|
if (wc.status != IBV_WC_SUCCESS) {
|
|
fprintf(stderr, "ibv_poll_cq wc.status=%d %s!\n",
|
|
wc.status, ibv_wc_status_str(wc.status));
|
|
fprintf(stderr, "ibv_poll_cq wrid=%s!\n", wrid_desc[wr_id]);
|
|
|
|
return -1;
|
|
}
|
|
|
|
if (rdma->control_ready_expected &&
|
|
(wr_id >= RDMA_WRID_RECV_CONTROL)) {
|
|
trace_qemu_rdma_poll_recv(wrid_desc[RDMA_WRID_RECV_CONTROL],
|
|
wr_id - RDMA_WRID_RECV_CONTROL, wr_id, rdma->nb_sent);
|
|
rdma->control_ready_expected = 0;
|
|
}
|
|
|
|
if (wr_id == RDMA_WRID_RDMA_WRITE) {
|
|
uint64_t chunk =
|
|
(wc.wr_id & RDMA_WRID_CHUNK_MASK) >> RDMA_WRID_CHUNK_SHIFT;
|
|
uint64_t index =
|
|
(wc.wr_id & RDMA_WRID_BLOCK_MASK) >> RDMA_WRID_BLOCK_SHIFT;
|
|
RDMALocalBlock *block = &(rdma->local_ram_blocks.block[index]);
|
|
|
|
trace_qemu_rdma_poll_write(print_wrid(wr_id), wr_id, rdma->nb_sent,
|
|
index, chunk, block->local_host_addr,
|
|
(void *)(uintptr_t)block->remote_host_addr);
|
|
|
|
clear_bit(chunk, block->transit_bitmap);
|
|
|
|
if (rdma->nb_sent > 0) {
|
|
rdma->nb_sent--;
|
|
}
|
|
|
|
if (!rdma->pin_all) {
|
|
/*
|
|
* FYI: If one wanted to signal a specific chunk to be unregistered
|
|
* using LRU or workload-specific information, this is the function
|
|
* you would call to do so. That chunk would then get asynchronously
|
|
* unregistered later.
|
|
*/
|
|
#ifdef RDMA_UNREGISTRATION_EXAMPLE
|
|
qemu_rdma_signal_unregister(rdma, index, chunk, wc.wr_id);
|
|
#endif
|
|
}
|
|
} else {
|
|
trace_qemu_rdma_poll_other(print_wrid(wr_id), wr_id, rdma->nb_sent);
|
|
}
|
|
|
|
*wr_id_out = wc.wr_id;
|
|
if (byte_len) {
|
|
*byte_len = wc.byte_len;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Block until the next work request has completed.
|
|
*
|
|
* First poll to see if a work request has already completed,
|
|
* otherwise block.
|
|
*
|
|
* If we encounter completed work requests for IDs other than
|
|
* the one we're interested in, then that's generally an error.
|
|
*
|
|
* The only exception is actual RDMA Write completions. These
|
|
* completions only need to be recorded, but do not actually
|
|
* need further processing.
|
|
*/
|
|
static int qemu_rdma_block_for_wrid(RDMAContext *rdma, int wrid_requested,
|
|
uint32_t *byte_len)
|
|
{
|
|
int num_cq_events = 0, ret = 0;
|
|
struct ibv_cq *cq;
|
|
void *cq_ctx;
|
|
uint64_t wr_id = RDMA_WRID_NONE, wr_id_in;
|
|
|
|
if (ibv_req_notify_cq(rdma->cq, 0)) {
|
|
return -1;
|
|
}
|
|
/* poll cq first */
|
|
while (wr_id != wrid_requested) {
|
|
ret = qemu_rdma_poll(rdma, &wr_id_in, byte_len);
|
|
if (ret < 0) {
|
|
return ret;
|
|
}
|
|
|
|
wr_id = wr_id_in & RDMA_WRID_TYPE_MASK;
|
|
|
|
if (wr_id == RDMA_WRID_NONE) {
|
|
break;
|
|
}
|
|
if (wr_id != wrid_requested) {
|
|
trace_qemu_rdma_block_for_wrid_miss(print_wrid(wrid_requested),
|
|
wrid_requested, print_wrid(wr_id), wr_id);
|
|
}
|
|
}
|
|
|
|
if (wr_id == wrid_requested) {
|
|
return 0;
|
|
}
|
|
|
|
while (1) {
|
|
/*
|
|
* Coroutine doesn't start until process_incoming_migration()
|
|
* so don't yield unless we know we're running inside of a coroutine.
|
|
*/
|
|
if (rdma->migration_started_on_destination) {
|
|
yield_until_fd_readable(rdma->comp_channel->fd);
|
|
}
|
|
|
|
if (ibv_get_cq_event(rdma->comp_channel, &cq, &cq_ctx)) {
|
|
perror("ibv_get_cq_event");
|
|
goto err_block_for_wrid;
|
|
}
|
|
|
|
num_cq_events++;
|
|
|
|
if (ibv_req_notify_cq(cq, 0)) {
|
|
goto err_block_for_wrid;
|
|
}
|
|
|
|
while (wr_id != wrid_requested) {
|
|
ret = qemu_rdma_poll(rdma, &wr_id_in, byte_len);
|
|
if (ret < 0) {
|
|
goto err_block_for_wrid;
|
|
}
|
|
|
|
wr_id = wr_id_in & RDMA_WRID_TYPE_MASK;
|
|
|
|
if (wr_id == RDMA_WRID_NONE) {
|
|
break;
|
|
}
|
|
if (wr_id != wrid_requested) {
|
|
trace_qemu_rdma_block_for_wrid_miss(print_wrid(wrid_requested),
|
|
wrid_requested, print_wrid(wr_id), wr_id);
|
|
}
|
|
}
|
|
|
|
if (wr_id == wrid_requested) {
|
|
goto success_block_for_wrid;
|
|
}
|
|
}
|
|
|
|
success_block_for_wrid:
|
|
if (num_cq_events) {
|
|
ibv_ack_cq_events(cq, num_cq_events);
|
|
}
|
|
return 0;
|
|
|
|
err_block_for_wrid:
|
|
if (num_cq_events) {
|
|
ibv_ack_cq_events(cq, num_cq_events);
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* Post a SEND message work request for the control channel
|
|
* containing some data and block until the post completes.
|
|
*/
|
|
static int qemu_rdma_post_send_control(RDMAContext *rdma, uint8_t *buf,
|
|
RDMAControlHeader *head)
|
|
{
|
|
int ret = 0;
|
|
RDMAWorkRequestData *wr = &rdma->wr_data[RDMA_WRID_CONTROL];
|
|
struct ibv_send_wr *bad_wr;
|
|
struct ibv_sge sge = {
|
|
.addr = (uintptr_t)(wr->control),
|
|
.length = head->len + sizeof(RDMAControlHeader),
|
|
.lkey = wr->control_mr->lkey,
|
|
};
|
|
struct ibv_send_wr send_wr = {
|
|
.wr_id = RDMA_WRID_SEND_CONTROL,
|
|
.opcode = IBV_WR_SEND,
|
|
.send_flags = IBV_SEND_SIGNALED,
|
|
.sg_list = &sge,
|
|
.num_sge = 1,
|
|
};
|
|
|
|
trace_qemu_rdma_post_send_control(control_desc[head->type]);
|
|
|
|
/*
|
|
* We don't actually need to do a memcpy() in here if we used
|
|
* the "sge" properly, but since we're only sending control messages
|
|
* (not RAM in a performance-critical path), then its OK for now.
|
|
*
|
|
* The copy makes the RDMAControlHeader simpler to manipulate
|
|
* for the time being.
|
|
*/
|
|
assert(head->len <= RDMA_CONTROL_MAX_BUFFER - sizeof(*head));
|
|
memcpy(wr->control, head, sizeof(RDMAControlHeader));
|
|
control_to_network((void *) wr->control);
|
|
|
|
if (buf) {
|
|
memcpy(wr->control + sizeof(RDMAControlHeader), buf, head->len);
|
|
}
|
|
|
|
|
|
ret = ibv_post_send(rdma->qp, &send_wr, &bad_wr);
|
|
|
|
if (ret > 0) {
|
|
error_report("Failed to use post IB SEND for control");
|
|
return -ret;
|
|
}
|
|
|
|
ret = qemu_rdma_block_for_wrid(rdma, RDMA_WRID_SEND_CONTROL, NULL);
|
|
if (ret < 0) {
|
|
error_report("rdma migration: send polling control error");
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* Post a RECV work request in anticipation of some future receipt
|
|
* of data on the control channel.
|
|
*/
|
|
static int qemu_rdma_post_recv_control(RDMAContext *rdma, int idx)
|
|
{
|
|
struct ibv_recv_wr *bad_wr;
|
|
struct ibv_sge sge = {
|
|
.addr = (uintptr_t)(rdma->wr_data[idx].control),
|
|
.length = RDMA_CONTROL_MAX_BUFFER,
|
|
.lkey = rdma->wr_data[idx].control_mr->lkey,
|
|
};
|
|
|
|
struct ibv_recv_wr recv_wr = {
|
|
.wr_id = RDMA_WRID_RECV_CONTROL + idx,
|
|
.sg_list = &sge,
|
|
.num_sge = 1,
|
|
};
|
|
|
|
|
|
if (ibv_post_recv(rdma->qp, &recv_wr, &bad_wr)) {
|
|
return -1;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Block and wait for a RECV control channel message to arrive.
|
|
*/
|
|
static int qemu_rdma_exchange_get_response(RDMAContext *rdma,
|
|
RDMAControlHeader *head, int expecting, int idx)
|
|
{
|
|
uint32_t byte_len;
|
|
int ret = qemu_rdma_block_for_wrid(rdma, RDMA_WRID_RECV_CONTROL + idx,
|
|
&byte_len);
|
|
|
|
if (ret < 0) {
|
|
error_report("rdma migration: recv polling control error!");
|
|
return ret;
|
|
}
|
|
|
|
network_to_control((void *) rdma->wr_data[idx].control);
|
|
memcpy(head, rdma->wr_data[idx].control, sizeof(RDMAControlHeader));
|
|
|
|
trace_qemu_rdma_exchange_get_response_start(control_desc[expecting]);
|
|
|
|
if (expecting == RDMA_CONTROL_NONE) {
|
|
trace_qemu_rdma_exchange_get_response_none(control_desc[head->type],
|
|
head->type);
|
|
} else if (head->type != expecting || head->type == RDMA_CONTROL_ERROR) {
|
|
error_report("Was expecting a %s (%d) control message"
|
|
", but got: %s (%d), length: %d",
|
|
control_desc[expecting], expecting,
|
|
control_desc[head->type], head->type, head->len);
|
|
return -EIO;
|
|
}
|
|
if (head->len > RDMA_CONTROL_MAX_BUFFER - sizeof(*head)) {
|
|
error_report("too long length: %d", head->len);
|
|
return -EINVAL;
|
|
}
|
|
if (sizeof(*head) + head->len != byte_len) {
|
|
error_report("Malformed length: %d byte_len %d", head->len, byte_len);
|
|
return -EINVAL;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* When a RECV work request has completed, the work request's
|
|
* buffer is pointed at the header.
|
|
*
|
|
* This will advance the pointer to the data portion
|
|
* of the control message of the work request's buffer that
|
|
* was populated after the work request finished.
|
|
*/
|
|
static void qemu_rdma_move_header(RDMAContext *rdma, int idx,
|
|
RDMAControlHeader *head)
|
|
{
|
|
rdma->wr_data[idx].control_len = head->len;
|
|
rdma->wr_data[idx].control_curr =
|
|
rdma->wr_data[idx].control + sizeof(RDMAControlHeader);
|
|
}
|
|
|
|
/*
|
|
* This is an 'atomic' high-level operation to deliver a single, unified
|
|
* control-channel message.
|
|
*
|
|
* Additionally, if the user is expecting some kind of reply to this message,
|
|
* they can request a 'resp' response message be filled in by posting an
|
|
* additional work request on behalf of the user and waiting for an additional
|
|
* completion.
|
|
*
|
|
* The extra (optional) response is used during registration to us from having
|
|
* to perform an *additional* exchange of message just to provide a response by
|
|
* instead piggy-backing on the acknowledgement.
|
|
*/
|
|
static int qemu_rdma_exchange_send(RDMAContext *rdma, RDMAControlHeader *head,
|
|
uint8_t *data, RDMAControlHeader *resp,
|
|
int *resp_idx,
|
|
int (*callback)(RDMAContext *rdma))
|
|
{
|
|
int ret = 0;
|
|
|
|
/*
|
|
* Wait until the dest is ready before attempting to deliver the message
|
|
* by waiting for a READY message.
|
|
*/
|
|
if (rdma->control_ready_expected) {
|
|
RDMAControlHeader resp;
|
|
ret = qemu_rdma_exchange_get_response(rdma,
|
|
&resp, RDMA_CONTROL_READY, RDMA_WRID_READY);
|
|
if (ret < 0) {
|
|
return ret;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* If the user is expecting a response, post a WR in anticipation of it.
|
|
*/
|
|
if (resp) {
|
|
ret = qemu_rdma_post_recv_control(rdma, RDMA_WRID_DATA);
|
|
if (ret) {
|
|
error_report("rdma migration: error posting"
|
|
" extra control recv for anticipated result!");
|
|
return ret;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Post a WR to replace the one we just consumed for the READY message.
|
|
*/
|
|
ret = qemu_rdma_post_recv_control(rdma, RDMA_WRID_READY);
|
|
if (ret) {
|
|
error_report("rdma migration: error posting first control recv!");
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* Deliver the control message that was requested.
|
|
*/
|
|
ret = qemu_rdma_post_send_control(rdma, data, head);
|
|
|
|
if (ret < 0) {
|
|
error_report("Failed to send control buffer!");
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* If we're expecting a response, block and wait for it.
|
|
*/
|
|
if (resp) {
|
|
if (callback) {
|
|
trace_qemu_rdma_exchange_send_issue_callback();
|
|
ret = callback(rdma);
|
|
if (ret < 0) {
|
|
return ret;
|
|
}
|
|
}
|
|
|
|
trace_qemu_rdma_exchange_send_waiting(control_desc[resp->type]);
|
|
ret = qemu_rdma_exchange_get_response(rdma, resp,
|
|
resp->type, RDMA_WRID_DATA);
|
|
|
|
if (ret < 0) {
|
|
return ret;
|
|
}
|
|
|
|
qemu_rdma_move_header(rdma, RDMA_WRID_DATA, resp);
|
|
if (resp_idx) {
|
|
*resp_idx = RDMA_WRID_DATA;
|
|
}
|
|
trace_qemu_rdma_exchange_send_received(control_desc[resp->type]);
|
|
}
|
|
|
|
rdma->control_ready_expected = 1;
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* This is an 'atomic' high-level operation to receive a single, unified
|
|
* control-channel message.
|
|
*/
|
|
static int qemu_rdma_exchange_recv(RDMAContext *rdma, RDMAControlHeader *head,
|
|
int expecting)
|
|
{
|
|
RDMAControlHeader ready = {
|
|
.len = 0,
|
|
.type = RDMA_CONTROL_READY,
|
|
.repeat = 1,
|
|
};
|
|
int ret;
|
|
|
|
/*
|
|
* Inform the source that we're ready to receive a message.
|
|
*/
|
|
ret = qemu_rdma_post_send_control(rdma, NULL, &ready);
|
|
|
|
if (ret < 0) {
|
|
error_report("Failed to send control buffer!");
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* Block and wait for the message.
|
|
*/
|
|
ret = qemu_rdma_exchange_get_response(rdma, head,
|
|
expecting, RDMA_WRID_READY);
|
|
|
|
if (ret < 0) {
|
|
return ret;
|
|
}
|
|
|
|
qemu_rdma_move_header(rdma, RDMA_WRID_READY, head);
|
|
|
|
/*
|
|
* Post a new RECV work request to replace the one we just consumed.
|
|
*/
|
|
ret = qemu_rdma_post_recv_control(rdma, RDMA_WRID_READY);
|
|
if (ret) {
|
|
error_report("rdma migration: error posting second control recv!");
|
|
return ret;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Write an actual chunk of memory using RDMA.
|
|
*
|
|
* If we're using dynamic registration on the dest-side, we have to
|
|
* send a registration command first.
|
|
*/
|
|
static int qemu_rdma_write_one(QEMUFile *f, RDMAContext *rdma,
|
|
int current_index, uint64_t current_addr,
|
|
uint64_t length)
|
|
{
|
|
struct ibv_sge sge;
|
|
struct ibv_send_wr send_wr = { 0 };
|
|
struct ibv_send_wr *bad_wr;
|
|
int reg_result_idx, ret, count = 0;
|
|
uint64_t chunk, chunks;
|
|
uint8_t *chunk_start, *chunk_end;
|
|
RDMALocalBlock *block = &(rdma->local_ram_blocks.block[current_index]);
|
|
RDMARegister reg;
|
|
RDMARegisterResult *reg_result;
|
|
RDMAControlHeader resp = { .type = RDMA_CONTROL_REGISTER_RESULT };
|
|
RDMAControlHeader head = { .len = sizeof(RDMARegister),
|
|
.type = RDMA_CONTROL_REGISTER_REQUEST,
|
|
.repeat = 1,
|
|
};
|
|
|
|
retry:
|
|
sge.addr = (uintptr_t)(block->local_host_addr +
|
|
(current_addr - block->offset));
|
|
sge.length = length;
|
|
|
|
chunk = ram_chunk_index(block->local_host_addr,
|
|
(uint8_t *)(uintptr_t)sge.addr);
|
|
chunk_start = ram_chunk_start(block, chunk);
|
|
|
|
if (block->is_ram_block) {
|
|
chunks = length / (1UL << RDMA_REG_CHUNK_SHIFT);
|
|
|
|
if (chunks && ((length % (1UL << RDMA_REG_CHUNK_SHIFT)) == 0)) {
|
|
chunks--;
|
|
}
|
|
} else {
|
|
chunks = block->length / (1UL << RDMA_REG_CHUNK_SHIFT);
|
|
|
|
if (chunks && ((block->length % (1UL << RDMA_REG_CHUNK_SHIFT)) == 0)) {
|
|
chunks--;
|
|
}
|
|
}
|
|
|
|
trace_qemu_rdma_write_one_top(chunks + 1,
|
|
(chunks + 1) *
|
|
(1UL << RDMA_REG_CHUNK_SHIFT) / 1024 / 1024);
|
|
|
|
chunk_end = ram_chunk_end(block, chunk + chunks);
|
|
|
|
if (!rdma->pin_all) {
|
|
#ifdef RDMA_UNREGISTRATION_EXAMPLE
|
|
qemu_rdma_unregister_waiting(rdma);
|
|
#endif
|
|
}
|
|
|
|
while (test_bit(chunk, block->transit_bitmap)) {
|
|
(void)count;
|
|
trace_qemu_rdma_write_one_block(count++, current_index, chunk,
|
|
sge.addr, length, rdma->nb_sent, block->nb_chunks);
|
|
|
|
ret = qemu_rdma_block_for_wrid(rdma, RDMA_WRID_RDMA_WRITE, NULL);
|
|
|
|
if (ret < 0) {
|
|
error_report("Failed to Wait for previous write to complete "
|
|
"block %d chunk %" PRIu64
|
|
" current %" PRIu64 " len %" PRIu64 " %d",
|
|
current_index, chunk, sge.addr, length, rdma->nb_sent);
|
|
return ret;
|
|
}
|
|
}
|
|
|
|
if (!rdma->pin_all || !block->is_ram_block) {
|
|
if (!block->remote_keys[chunk]) {
|
|
/*
|
|
* This chunk has not yet been registered, so first check to see
|
|
* if the entire chunk is zero. If so, tell the other size to
|
|
* memset() + madvise() the entire chunk without RDMA.
|
|
*/
|
|
|
|
if (can_use_buffer_find_nonzero_offset((void *)(uintptr_t)sge.addr,
|
|
length)
|
|
&& buffer_find_nonzero_offset((void *)(uintptr_t)sge.addr,
|
|
length) == length) {
|
|
RDMACompress comp = {
|
|
.offset = current_addr,
|
|
.value = 0,
|
|
.block_idx = current_index,
|
|
.length = length,
|
|
};
|
|
|
|
head.len = sizeof(comp);
|
|
head.type = RDMA_CONTROL_COMPRESS;
|
|
|
|
trace_qemu_rdma_write_one_zero(chunk, sge.length,
|
|
current_index, current_addr);
|
|
|
|
compress_to_network(&comp);
|
|
ret = qemu_rdma_exchange_send(rdma, &head,
|
|
(uint8_t *) &comp, NULL, NULL, NULL);
|
|
|
|
if (ret < 0) {
|
|
return -EIO;
|
|
}
|
|
|
|
acct_update_position(f, sge.length, true);
|
|
|
|
return 1;
|
|
}
|
|
|
|
/*
|
|
* Otherwise, tell other side to register.
|
|
*/
|
|
reg.current_index = current_index;
|
|
if (block->is_ram_block) {
|
|
reg.key.current_addr = current_addr;
|
|
} else {
|
|
reg.key.chunk = chunk;
|
|
}
|
|
reg.chunks = chunks;
|
|
|
|
trace_qemu_rdma_write_one_sendreg(chunk, sge.length, current_index,
|
|
current_addr);
|
|
|
|
register_to_network(®);
|
|
ret = qemu_rdma_exchange_send(rdma, &head, (uint8_t *) ®,
|
|
&resp, ®_result_idx, NULL);
|
|
if (ret < 0) {
|
|
return ret;
|
|
}
|
|
|
|
/* try to overlap this single registration with the one we sent. */
|
|
if (qemu_rdma_register_and_get_keys(rdma, block, sge.addr,
|
|
&sge.lkey, NULL, chunk,
|
|
chunk_start, chunk_end)) {
|
|
error_report("cannot get lkey");
|
|
return -EINVAL;
|
|
}
|
|
|
|
reg_result = (RDMARegisterResult *)
|
|
rdma->wr_data[reg_result_idx].control_curr;
|
|
|
|
network_to_result(reg_result);
|
|
|
|
trace_qemu_rdma_write_one_recvregres(block->remote_keys[chunk],
|
|
reg_result->rkey, chunk);
|
|
|
|
block->remote_keys[chunk] = reg_result->rkey;
|
|
block->remote_host_addr = reg_result->host_addr;
|
|
} else {
|
|
/* already registered before */
|
|
if (qemu_rdma_register_and_get_keys(rdma, block, sge.addr,
|
|
&sge.lkey, NULL, chunk,
|
|
chunk_start, chunk_end)) {
|
|
error_report("cannot get lkey!");
|
|
return -EINVAL;
|
|
}
|
|
}
|
|
|
|
send_wr.wr.rdma.rkey = block->remote_keys[chunk];
|
|
} else {
|
|
send_wr.wr.rdma.rkey = block->remote_rkey;
|
|
|
|
if (qemu_rdma_register_and_get_keys(rdma, block, sge.addr,
|
|
&sge.lkey, NULL, chunk,
|
|
chunk_start, chunk_end)) {
|
|
error_report("cannot get lkey!");
|
|
return -EINVAL;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Encode the ram block index and chunk within this wrid.
|
|
* We will use this information at the time of completion
|
|
* to figure out which bitmap to check against and then which
|
|
* chunk in the bitmap to look for.
|
|
*/
|
|
send_wr.wr_id = qemu_rdma_make_wrid(RDMA_WRID_RDMA_WRITE,
|
|
current_index, chunk);
|
|
|
|
send_wr.opcode = IBV_WR_RDMA_WRITE;
|
|
send_wr.send_flags = IBV_SEND_SIGNALED;
|
|
send_wr.sg_list = &sge;
|
|
send_wr.num_sge = 1;
|
|
send_wr.wr.rdma.remote_addr = block->remote_host_addr +
|
|
(current_addr - block->offset);
|
|
|
|
trace_qemu_rdma_write_one_post(chunk, sge.addr, send_wr.wr.rdma.remote_addr,
|
|
sge.length);
|
|
|
|
/*
|
|
* ibv_post_send() does not return negative error numbers,
|
|
* per the specification they are positive - no idea why.
|
|
*/
|
|
ret = ibv_post_send(rdma->qp, &send_wr, &bad_wr);
|
|
|
|
if (ret == ENOMEM) {
|
|
trace_qemu_rdma_write_one_queue_full();
|
|
ret = qemu_rdma_block_for_wrid(rdma, RDMA_WRID_RDMA_WRITE, NULL);
|
|
if (ret < 0) {
|
|
error_report("rdma migration: failed to make "
|
|
"room in full send queue! %d", ret);
|
|
return ret;
|
|
}
|
|
|
|
goto retry;
|
|
|
|
} else if (ret > 0) {
|
|
perror("rdma migration: post rdma write failed");
|
|
return -ret;
|
|
}
|
|
|
|
set_bit(chunk, block->transit_bitmap);
|
|
acct_update_position(f, sge.length, false);
|
|
rdma->total_writes++;
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Push out any unwritten RDMA operations.
|
|
*
|
|
* We support sending out multiple chunks at the same time.
|
|
* Not all of them need to get signaled in the completion queue.
|
|
*/
|
|
static int qemu_rdma_write_flush(QEMUFile *f, RDMAContext *rdma)
|
|
{
|
|
int ret;
|
|
|
|
if (!rdma->current_length) {
|
|
return 0;
|
|
}
|
|
|
|
ret = qemu_rdma_write_one(f, rdma,
|
|
rdma->current_index, rdma->current_addr, rdma->current_length);
|
|
|
|
if (ret < 0) {
|
|
return ret;
|
|
}
|
|
|
|
if (ret == 0) {
|
|
rdma->nb_sent++;
|
|
trace_qemu_rdma_write_flush(rdma->nb_sent);
|
|
}
|
|
|
|
rdma->current_length = 0;
|
|
rdma->current_addr = 0;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static inline int qemu_rdma_buffer_mergable(RDMAContext *rdma,
|
|
uint64_t offset, uint64_t len)
|
|
{
|
|
RDMALocalBlock *block;
|
|
uint8_t *host_addr;
|
|
uint8_t *chunk_end;
|
|
|
|
if (rdma->current_index < 0) {
|
|
return 0;
|
|
}
|
|
|
|
if (rdma->current_chunk < 0) {
|
|
return 0;
|
|
}
|
|
|
|
block = &(rdma->local_ram_blocks.block[rdma->current_index]);
|
|
host_addr = block->local_host_addr + (offset - block->offset);
|
|
chunk_end = ram_chunk_end(block, rdma->current_chunk);
|
|
|
|
if (rdma->current_length == 0) {
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Only merge into chunk sequentially.
|
|
*/
|
|
if (offset != (rdma->current_addr + rdma->current_length)) {
|
|
return 0;
|
|
}
|
|
|
|
if (offset < block->offset) {
|
|
return 0;
|
|
}
|
|
|
|
if ((offset + len) > (block->offset + block->length)) {
|
|
return 0;
|
|
}
|
|
|
|
if ((host_addr + len) > chunk_end) {
|
|
return 0;
|
|
}
|
|
|
|
return 1;
|
|
}
|
|
|
|
/*
|
|
* We're not actually writing here, but doing three things:
|
|
*
|
|
* 1. Identify the chunk the buffer belongs to.
|
|
* 2. If the chunk is full or the buffer doesn't belong to the current
|
|
* chunk, then start a new chunk and flush() the old chunk.
|
|
* 3. To keep the hardware busy, we also group chunks into batches
|
|
* and only require that a batch gets acknowledged in the completion
|
|
* qeueue instead of each individual chunk.
|
|
*/
|
|
static int qemu_rdma_write(QEMUFile *f, RDMAContext *rdma,
|
|
uint64_t block_offset, uint64_t offset,
|
|
uint64_t len)
|
|
{
|
|
uint64_t current_addr = block_offset + offset;
|
|
uint64_t index = rdma->current_index;
|
|
uint64_t chunk = rdma->current_chunk;
|
|
int ret;
|
|
|
|
/* If we cannot merge it, we flush the current buffer first. */
|
|
if (!qemu_rdma_buffer_mergable(rdma, current_addr, len)) {
|
|
ret = qemu_rdma_write_flush(f, rdma);
|
|
if (ret) {
|
|
return ret;
|
|
}
|
|
rdma->current_length = 0;
|
|
rdma->current_addr = current_addr;
|
|
|
|
ret = qemu_rdma_search_ram_block(rdma, block_offset,
|
|
offset, len, &index, &chunk);
|
|
if (ret) {
|
|
error_report("ram block search failed");
|
|
return ret;
|
|
}
|
|
rdma->current_index = index;
|
|
rdma->current_chunk = chunk;
|
|
}
|
|
|
|
/* merge it */
|
|
rdma->current_length += len;
|
|
|
|
/* flush it if buffer is too large */
|
|
if (rdma->current_length >= RDMA_MERGE_MAX) {
|
|
return qemu_rdma_write_flush(f, rdma);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void qemu_rdma_cleanup(RDMAContext *rdma)
|
|
{
|
|
struct rdma_cm_event *cm_event;
|
|
int ret, idx;
|
|
|
|
if (rdma->cm_id && rdma->connected) {
|
|
if (rdma->error_state) {
|
|
RDMAControlHeader head = { .len = 0,
|
|
.type = RDMA_CONTROL_ERROR,
|
|
.repeat = 1,
|
|
};
|
|
error_report("Early error. Sending error.");
|
|
qemu_rdma_post_send_control(rdma, NULL, &head);
|
|
}
|
|
|
|
ret = rdma_disconnect(rdma->cm_id);
|
|
if (!ret) {
|
|
trace_qemu_rdma_cleanup_waiting_for_disconnect();
|
|
ret = rdma_get_cm_event(rdma->channel, &cm_event);
|
|
if (!ret) {
|
|
rdma_ack_cm_event(cm_event);
|
|
}
|
|
}
|
|
trace_qemu_rdma_cleanup_disconnect();
|
|
rdma->connected = false;
|
|
}
|
|
|
|
g_free(rdma->block);
|
|
rdma->block = NULL;
|
|
|
|
for (idx = 0; idx < RDMA_WRID_MAX; idx++) {
|
|
if (rdma->wr_data[idx].control_mr) {
|
|
rdma->total_registrations--;
|
|
ibv_dereg_mr(rdma->wr_data[idx].control_mr);
|
|
}
|
|
rdma->wr_data[idx].control_mr = NULL;
|
|
}
|
|
|
|
if (rdma->local_ram_blocks.block) {
|
|
while (rdma->local_ram_blocks.nb_blocks) {
|
|
rdma_delete_block(rdma, rdma->local_ram_blocks.block->offset);
|
|
}
|
|
}
|
|
|
|
if (rdma->qp) {
|
|
rdma_destroy_qp(rdma->cm_id);
|
|
rdma->qp = NULL;
|
|
}
|
|
if (rdma->cq) {
|
|
ibv_destroy_cq(rdma->cq);
|
|
rdma->cq = NULL;
|
|
}
|
|
if (rdma->comp_channel) {
|
|
ibv_destroy_comp_channel(rdma->comp_channel);
|
|
rdma->comp_channel = NULL;
|
|
}
|
|
if (rdma->pd) {
|
|
ibv_dealloc_pd(rdma->pd);
|
|
rdma->pd = NULL;
|
|
}
|
|
if (rdma->cm_id) {
|
|
rdma_destroy_id(rdma->cm_id);
|
|
rdma->cm_id = NULL;
|
|
}
|
|
if (rdma->listen_id) {
|
|
rdma_destroy_id(rdma->listen_id);
|
|
rdma->listen_id = NULL;
|
|
}
|
|
if (rdma->channel) {
|
|
rdma_destroy_event_channel(rdma->channel);
|
|
rdma->channel = NULL;
|
|
}
|
|
g_free(rdma->host);
|
|
rdma->host = NULL;
|
|
}
|
|
|
|
|
|
static int qemu_rdma_source_init(RDMAContext *rdma, Error **errp, bool pin_all)
|
|
{
|
|
int ret, idx;
|
|
Error *local_err = NULL, **temp = &local_err;
|
|
|
|
/*
|
|
* Will be validated against destination's actual capabilities
|
|
* after the connect() completes.
|
|
*/
|
|
rdma->pin_all = pin_all;
|
|
|
|
ret = qemu_rdma_resolve_host(rdma, temp);
|
|
if (ret) {
|
|
goto err_rdma_source_init;
|
|
}
|
|
|
|
ret = qemu_rdma_alloc_pd_cq(rdma);
|
|
if (ret) {
|
|
ERROR(temp, "rdma migration: error allocating pd and cq! Your mlock()"
|
|
" limits may be too low. Please check $ ulimit -a # and "
|
|
"search for 'ulimit -l' in the output");
|
|
goto err_rdma_source_init;
|
|
}
|
|
|
|
ret = qemu_rdma_alloc_qp(rdma);
|
|
if (ret) {
|
|
ERROR(temp, "rdma migration: error allocating qp!");
|
|
goto err_rdma_source_init;
|
|
}
|
|
|
|
ret = qemu_rdma_init_ram_blocks(rdma);
|
|
if (ret) {
|
|
ERROR(temp, "rdma migration: error initializing ram blocks!");
|
|
goto err_rdma_source_init;
|
|
}
|
|
|
|
for (idx = 0; idx < RDMA_WRID_MAX; idx++) {
|
|
ret = qemu_rdma_reg_control(rdma, idx);
|
|
if (ret) {
|
|
ERROR(temp, "rdma migration: error registering %d control!",
|
|
idx);
|
|
goto err_rdma_source_init;
|
|
}
|
|
}
|
|
|
|
return 0;
|
|
|
|
err_rdma_source_init:
|
|
error_propagate(errp, local_err);
|
|
qemu_rdma_cleanup(rdma);
|
|
return -1;
|
|
}
|
|
|
|
static int qemu_rdma_connect(RDMAContext *rdma, Error **errp)
|
|
{
|
|
RDMACapabilities cap = {
|
|
.version = RDMA_CONTROL_VERSION_CURRENT,
|
|
.flags = 0,
|
|
};
|
|
struct rdma_conn_param conn_param = { .initiator_depth = 2,
|
|
.retry_count = 5,
|
|
.private_data = &cap,
|
|
.private_data_len = sizeof(cap),
|
|
};
|
|
struct rdma_cm_event *cm_event;
|
|
int ret;
|
|
|
|
/*
|
|
* Only negotiate the capability with destination if the user
|
|
* on the source first requested the capability.
|
|
*/
|
|
if (rdma->pin_all) {
|
|
trace_qemu_rdma_connect_pin_all_requested();
|
|
cap.flags |= RDMA_CAPABILITY_PIN_ALL;
|
|
}
|
|
|
|
caps_to_network(&cap);
|
|
|
|
ret = rdma_connect(rdma->cm_id, &conn_param);
|
|
if (ret) {
|
|
perror("rdma_connect");
|
|
ERROR(errp, "connecting to destination!");
|
|
goto err_rdma_source_connect;
|
|
}
|
|
|
|
ret = rdma_get_cm_event(rdma->channel, &cm_event);
|
|
if (ret) {
|
|
perror("rdma_get_cm_event after rdma_connect");
|
|
ERROR(errp, "connecting to destination!");
|
|
rdma_ack_cm_event(cm_event);
|
|
goto err_rdma_source_connect;
|
|
}
|
|
|
|
if (cm_event->event != RDMA_CM_EVENT_ESTABLISHED) {
|
|
perror("rdma_get_cm_event != EVENT_ESTABLISHED after rdma_connect");
|
|
ERROR(errp, "connecting to destination!");
|
|
rdma_ack_cm_event(cm_event);
|
|
goto err_rdma_source_connect;
|
|
}
|
|
rdma->connected = true;
|
|
|
|
memcpy(&cap, cm_event->param.conn.private_data, sizeof(cap));
|
|
network_to_caps(&cap);
|
|
|
|
/*
|
|
* Verify that the *requested* capabilities are supported by the destination
|
|
* and disable them otherwise.
|
|
*/
|
|
if (rdma->pin_all && !(cap.flags & RDMA_CAPABILITY_PIN_ALL)) {
|
|
ERROR(errp, "Server cannot support pinning all memory. "
|
|
"Will register memory dynamically.");
|
|
rdma->pin_all = false;
|
|
}
|
|
|
|
trace_qemu_rdma_connect_pin_all_outcome(rdma->pin_all);
|
|
|
|
rdma_ack_cm_event(cm_event);
|
|
|
|
ret = qemu_rdma_post_recv_control(rdma, RDMA_WRID_READY);
|
|
if (ret) {
|
|
ERROR(errp, "posting second control recv!");
|
|
goto err_rdma_source_connect;
|
|
}
|
|
|
|
rdma->control_ready_expected = 1;
|
|
rdma->nb_sent = 0;
|
|
return 0;
|
|
|
|
err_rdma_source_connect:
|
|
qemu_rdma_cleanup(rdma);
|
|
return -1;
|
|
}
|
|
|
|
static int qemu_rdma_dest_init(RDMAContext *rdma, Error **errp)
|
|
{
|
|
int ret, idx;
|
|
struct rdma_cm_id *listen_id;
|
|
char ip[40] = "unknown";
|
|
struct rdma_addrinfo *res, *e;
|
|
char port_str[16];
|
|
|
|
for (idx = 0; idx < RDMA_WRID_MAX; idx++) {
|
|
rdma->wr_data[idx].control_len = 0;
|
|
rdma->wr_data[idx].control_curr = NULL;
|
|
}
|
|
|
|
if (!rdma->host || !rdma->host[0]) {
|
|
ERROR(errp, "RDMA host is not set!");
|
|
rdma->error_state = -EINVAL;
|
|
return -1;
|
|
}
|
|
/* create CM channel */
|
|
rdma->channel = rdma_create_event_channel();
|
|
if (!rdma->channel) {
|
|
ERROR(errp, "could not create rdma event channel");
|
|
rdma->error_state = -EINVAL;
|
|
return -1;
|
|
}
|
|
|
|
/* create CM id */
|
|
ret = rdma_create_id(rdma->channel, &listen_id, NULL, RDMA_PS_TCP);
|
|
if (ret) {
|
|
ERROR(errp, "could not create cm_id!");
|
|
goto err_dest_init_create_listen_id;
|
|
}
|
|
|
|
snprintf(port_str, 16, "%d", rdma->port);
|
|
port_str[15] = '\0';
|
|
|
|
ret = rdma_getaddrinfo(rdma->host, port_str, NULL, &res);
|
|
if (ret < 0) {
|
|
ERROR(errp, "could not rdma_getaddrinfo address %s", rdma->host);
|
|
goto err_dest_init_bind_addr;
|
|
}
|
|
|
|
for (e = res; e != NULL; e = e->ai_next) {
|
|
inet_ntop(e->ai_family,
|
|
&((struct sockaddr_in *) e->ai_dst_addr)->sin_addr, ip, sizeof ip);
|
|
trace_qemu_rdma_dest_init_trying(rdma->host, ip);
|
|
ret = rdma_bind_addr(listen_id, e->ai_dst_addr);
|
|
if (ret) {
|
|
continue;
|
|
}
|
|
if (e->ai_family == AF_INET6) {
|
|
ret = qemu_rdma_broken_ipv6_kernel(errp, listen_id->verbs);
|
|
if (ret) {
|
|
continue;
|
|
}
|
|
}
|
|
break;
|
|
}
|
|
|
|
if (!e) {
|
|
ERROR(errp, "Error: could not rdma_bind_addr!");
|
|
goto err_dest_init_bind_addr;
|
|
}
|
|
|
|
rdma->listen_id = listen_id;
|
|
qemu_rdma_dump_gid("dest_init", listen_id);
|
|
return 0;
|
|
|
|
err_dest_init_bind_addr:
|
|
rdma_destroy_id(listen_id);
|
|
err_dest_init_create_listen_id:
|
|
rdma_destroy_event_channel(rdma->channel);
|
|
rdma->channel = NULL;
|
|
rdma->error_state = ret;
|
|
return ret;
|
|
|
|
}
|
|
|
|
static void *qemu_rdma_data_init(const char *host_port, Error **errp)
|
|
{
|
|
RDMAContext *rdma = NULL;
|
|
InetSocketAddress *addr;
|
|
|
|
if (host_port) {
|
|
rdma = g_malloc0(sizeof(RDMAContext));
|
|
memset(rdma, 0, sizeof(RDMAContext));
|
|
rdma->current_index = -1;
|
|
rdma->current_chunk = -1;
|
|
|
|
addr = inet_parse(host_port, NULL);
|
|
if (addr != NULL) {
|
|
rdma->port = atoi(addr->port);
|
|
rdma->host = g_strdup(addr->host);
|
|
} else {
|
|
ERROR(errp, "bad RDMA migration address '%s'", host_port);
|
|
g_free(rdma);
|
|
rdma = NULL;
|
|
}
|
|
|
|
qapi_free_InetSocketAddress(addr);
|
|
}
|
|
|
|
return rdma;
|
|
}
|
|
|
|
/*
|
|
* QEMUFile interface to the control channel.
|
|
* SEND messages for control only.
|
|
* VM's ram is handled with regular RDMA messages.
|
|
*/
|
|
static int qemu_rdma_put_buffer(void *opaque, const uint8_t *buf,
|
|
int64_t pos, int size)
|
|
{
|
|
QEMUFileRDMA *r = opaque;
|
|
QEMUFile *f = r->file;
|
|
RDMAContext *rdma = r->rdma;
|
|
size_t remaining = size;
|
|
uint8_t * data = (void *) buf;
|
|
int ret;
|
|
|
|
CHECK_ERROR_STATE();
|
|
|
|
/*
|
|
* Push out any writes that
|
|
* we're queued up for VM's ram.
|
|
*/
|
|
ret = qemu_rdma_write_flush(f, rdma);
|
|
if (ret < 0) {
|
|
rdma->error_state = ret;
|
|
return ret;
|
|
}
|
|
|
|
while (remaining) {
|
|
RDMAControlHeader head;
|
|
|
|
r->len = MIN(remaining, RDMA_SEND_INCREMENT);
|
|
remaining -= r->len;
|
|
|
|
head.len = r->len;
|
|
head.type = RDMA_CONTROL_QEMU_FILE;
|
|
|
|
ret = qemu_rdma_exchange_send(rdma, &head, data, NULL, NULL, NULL);
|
|
|
|
if (ret < 0) {
|
|
rdma->error_state = ret;
|
|
return ret;
|
|
}
|
|
|
|
data += r->len;
|
|
}
|
|
|
|
return size;
|
|
}
|
|
|
|
static size_t qemu_rdma_fill(RDMAContext *rdma, uint8_t *buf,
|
|
int size, int idx)
|
|
{
|
|
size_t len = 0;
|
|
|
|
if (rdma->wr_data[idx].control_len) {
|
|
trace_qemu_rdma_fill(rdma->wr_data[idx].control_len, size);
|
|
|
|
len = MIN(size, rdma->wr_data[idx].control_len);
|
|
memcpy(buf, rdma->wr_data[idx].control_curr, len);
|
|
rdma->wr_data[idx].control_curr += len;
|
|
rdma->wr_data[idx].control_len -= len;
|
|
}
|
|
|
|
return len;
|
|
}
|
|
|
|
/*
|
|
* QEMUFile interface to the control channel.
|
|
* RDMA links don't use bytestreams, so we have to
|
|
* return bytes to QEMUFile opportunistically.
|
|
*/
|
|
static int qemu_rdma_get_buffer(void *opaque, uint8_t *buf,
|
|
int64_t pos, int size)
|
|
{
|
|
QEMUFileRDMA *r = opaque;
|
|
RDMAContext *rdma = r->rdma;
|
|
RDMAControlHeader head;
|
|
int ret = 0;
|
|
|
|
CHECK_ERROR_STATE();
|
|
|
|
/*
|
|
* First, we hold on to the last SEND message we
|
|
* were given and dish out the bytes until we run
|
|
* out of bytes.
|
|
*/
|
|
r->len = qemu_rdma_fill(r->rdma, buf, size, 0);
|
|
if (r->len) {
|
|
return r->len;
|
|
}
|
|
|
|
/*
|
|
* Once we run out, we block and wait for another
|
|
* SEND message to arrive.
|
|
*/
|
|
ret = qemu_rdma_exchange_recv(rdma, &head, RDMA_CONTROL_QEMU_FILE);
|
|
|
|
if (ret < 0) {
|
|
rdma->error_state = ret;
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* SEND was received with new bytes, now try again.
|
|
*/
|
|
return qemu_rdma_fill(r->rdma, buf, size, 0);
|
|
}
|
|
|
|
/*
|
|
* Block until all the outstanding chunks have been delivered by the hardware.
|
|
*/
|
|
static int qemu_rdma_drain_cq(QEMUFile *f, RDMAContext *rdma)
|
|
{
|
|
int ret;
|
|
|
|
if (qemu_rdma_write_flush(f, rdma) < 0) {
|
|
return -EIO;
|
|
}
|
|
|
|
while (rdma->nb_sent) {
|
|
ret = qemu_rdma_block_for_wrid(rdma, RDMA_WRID_RDMA_WRITE, NULL);
|
|
if (ret < 0) {
|
|
error_report("rdma migration: complete polling error!");
|
|
return -EIO;
|
|
}
|
|
}
|
|
|
|
qemu_rdma_unregister_waiting(rdma);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int qemu_rdma_close(void *opaque)
|
|
{
|
|
trace_qemu_rdma_close();
|
|
QEMUFileRDMA *r = opaque;
|
|
if (r->rdma) {
|
|
qemu_rdma_cleanup(r->rdma);
|
|
g_free(r->rdma);
|
|
}
|
|
g_free(r);
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Parameters:
|
|
* @offset == 0 :
|
|
* This means that 'block_offset' is a full virtual address that does not
|
|
* belong to a RAMBlock of the virtual machine and instead
|
|
* represents a private malloc'd memory area that the caller wishes to
|
|
* transfer.
|
|
*
|
|
* @offset != 0 :
|
|
* Offset is an offset to be added to block_offset and used
|
|
* to also lookup the corresponding RAMBlock.
|
|
*
|
|
* @size > 0 :
|
|
* Initiate an transfer this size.
|
|
*
|
|
* @size == 0 :
|
|
* A 'hint' or 'advice' that means that we wish to speculatively
|
|
* and asynchronously unregister this memory. In this case, there is no
|
|
* guarantee that the unregister will actually happen, for example,
|
|
* if the memory is being actively transmitted. Additionally, the memory
|
|
* may be re-registered at any future time if a write within the same
|
|
* chunk was requested again, even if you attempted to unregister it
|
|
* here.
|
|
*
|
|
* @size < 0 : TODO, not yet supported
|
|
* Unregister the memory NOW. This means that the caller does not
|
|
* expect there to be any future RDMA transfers and we just want to clean
|
|
* things up. This is used in case the upper layer owns the memory and
|
|
* cannot wait for qemu_fclose() to occur.
|
|
*
|
|
* @bytes_sent : User-specificed pointer to indicate how many bytes were
|
|
* sent. Usually, this will not be more than a few bytes of
|
|
* the protocol because most transfers are sent asynchronously.
|
|
*/
|
|
static size_t qemu_rdma_save_page(QEMUFile *f, void *opaque,
|
|
ram_addr_t block_offset, ram_addr_t offset,
|
|
size_t size, uint64_t *bytes_sent)
|
|
{
|
|
QEMUFileRDMA *rfile = opaque;
|
|
RDMAContext *rdma = rfile->rdma;
|
|
int ret;
|
|
|
|
CHECK_ERROR_STATE();
|
|
|
|
qemu_fflush(f);
|
|
|
|
if (size > 0) {
|
|
/*
|
|
* Add this page to the current 'chunk'. If the chunk
|
|
* is full, or the page doen't belong to the current chunk,
|
|
* an actual RDMA write will occur and a new chunk will be formed.
|
|
*/
|
|
ret = qemu_rdma_write(f, rdma, block_offset, offset, size);
|
|
if (ret < 0) {
|
|
error_report("rdma migration: write error! %d", ret);
|
|
goto err;
|
|
}
|
|
|
|
/*
|
|
* We always return 1 bytes because the RDMA
|
|
* protocol is completely asynchronous. We do not yet know
|
|
* whether an identified chunk is zero or not because we're
|
|
* waiting for other pages to potentially be merged with
|
|
* the current chunk. So, we have to call qemu_update_position()
|
|
* later on when the actual write occurs.
|
|
*/
|
|
if (bytes_sent) {
|
|
*bytes_sent = 1;
|
|
}
|
|
} else {
|
|
uint64_t index, chunk;
|
|
|
|
/* TODO: Change QEMUFileOps prototype to be signed: size_t => long
|
|
if (size < 0) {
|
|
ret = qemu_rdma_drain_cq(f, rdma);
|
|
if (ret < 0) {
|
|
fprintf(stderr, "rdma: failed to synchronously drain"
|
|
" completion queue before unregistration.\n");
|
|
goto err;
|
|
}
|
|
}
|
|
*/
|
|
|
|
ret = qemu_rdma_search_ram_block(rdma, block_offset,
|
|
offset, size, &index, &chunk);
|
|
|
|
if (ret) {
|
|
error_report("ram block search failed");
|
|
goto err;
|
|
}
|
|
|
|
qemu_rdma_signal_unregister(rdma, index, chunk, 0);
|
|
|
|
/*
|
|
* TODO: Synchronous, guaranteed unregistration (should not occur during
|
|
* fast-path). Otherwise, unregisters will process on the next call to
|
|
* qemu_rdma_drain_cq()
|
|
if (size < 0) {
|
|
qemu_rdma_unregister_waiting(rdma);
|
|
}
|
|
*/
|
|
}
|
|
|
|
/*
|
|
* Drain the Completion Queue if possible, but do not block,
|
|
* just poll.
|
|
*
|
|
* If nothing to poll, the end of the iteration will do this
|
|
* again to make sure we don't overflow the request queue.
|
|
*/
|
|
while (1) {
|
|
uint64_t wr_id, wr_id_in;
|
|
int ret = qemu_rdma_poll(rdma, &wr_id_in, NULL);
|
|
if (ret < 0) {
|
|
error_report("rdma migration: polling error! %d", ret);
|
|
goto err;
|
|
}
|
|
|
|
wr_id = wr_id_in & RDMA_WRID_TYPE_MASK;
|
|
|
|
if (wr_id == RDMA_WRID_NONE) {
|
|
break;
|
|
}
|
|
}
|
|
|
|
return RAM_SAVE_CONTROL_DELAYED;
|
|
err:
|
|
rdma->error_state = ret;
|
|
return ret;
|
|
}
|
|
|
|
static int qemu_rdma_accept(RDMAContext *rdma)
|
|
{
|
|
RDMACapabilities cap;
|
|
struct rdma_conn_param conn_param = {
|
|
.responder_resources = 2,
|
|
.private_data = &cap,
|
|
.private_data_len = sizeof(cap),
|
|
};
|
|
struct rdma_cm_event *cm_event;
|
|
struct ibv_context *verbs;
|
|
int ret = -EINVAL;
|
|
int idx;
|
|
|
|
ret = rdma_get_cm_event(rdma->channel, &cm_event);
|
|
if (ret) {
|
|
goto err_rdma_dest_wait;
|
|
}
|
|
|
|
if (cm_event->event != RDMA_CM_EVENT_CONNECT_REQUEST) {
|
|
rdma_ack_cm_event(cm_event);
|
|
goto err_rdma_dest_wait;
|
|
}
|
|
|
|
memcpy(&cap, cm_event->param.conn.private_data, sizeof(cap));
|
|
|
|
network_to_caps(&cap);
|
|
|
|
if (cap.version < 1 || cap.version > RDMA_CONTROL_VERSION_CURRENT) {
|
|
error_report("Unknown source RDMA version: %d, bailing...",
|
|
cap.version);
|
|
rdma_ack_cm_event(cm_event);
|
|
goto err_rdma_dest_wait;
|
|
}
|
|
|
|
/*
|
|
* Respond with only the capabilities this version of QEMU knows about.
|
|
*/
|
|
cap.flags &= known_capabilities;
|
|
|
|
/*
|
|
* Enable the ones that we do know about.
|
|
* Add other checks here as new ones are introduced.
|
|
*/
|
|
if (cap.flags & RDMA_CAPABILITY_PIN_ALL) {
|
|
rdma->pin_all = true;
|
|
}
|
|
|
|
rdma->cm_id = cm_event->id;
|
|
verbs = cm_event->id->verbs;
|
|
|
|
rdma_ack_cm_event(cm_event);
|
|
|
|
trace_qemu_rdma_accept_pin_state(rdma->pin_all);
|
|
|
|
caps_to_network(&cap);
|
|
|
|
trace_qemu_rdma_accept_pin_verbsc(verbs);
|
|
|
|
if (!rdma->verbs) {
|
|
rdma->verbs = verbs;
|
|
} else if (rdma->verbs != verbs) {
|
|
error_report("ibv context not matching %p, %p!", rdma->verbs,
|
|
verbs);
|
|
goto err_rdma_dest_wait;
|
|
}
|
|
|
|
qemu_rdma_dump_id("dest_init", verbs);
|
|
|
|
ret = qemu_rdma_alloc_pd_cq(rdma);
|
|
if (ret) {
|
|
error_report("rdma migration: error allocating pd and cq!");
|
|
goto err_rdma_dest_wait;
|
|
}
|
|
|
|
ret = qemu_rdma_alloc_qp(rdma);
|
|
if (ret) {
|
|
error_report("rdma migration: error allocating qp!");
|
|
goto err_rdma_dest_wait;
|
|
}
|
|
|
|
ret = qemu_rdma_init_ram_blocks(rdma);
|
|
if (ret) {
|
|
error_report("rdma migration: error initializing ram blocks!");
|
|
goto err_rdma_dest_wait;
|
|
}
|
|
|
|
for (idx = 0; idx < RDMA_WRID_MAX; idx++) {
|
|
ret = qemu_rdma_reg_control(rdma, idx);
|
|
if (ret) {
|
|
error_report("rdma: error registering %d control", idx);
|
|
goto err_rdma_dest_wait;
|
|
}
|
|
}
|
|
|
|
qemu_set_fd_handler2(rdma->channel->fd, NULL, NULL, NULL, NULL);
|
|
|
|
ret = rdma_accept(rdma->cm_id, &conn_param);
|
|
if (ret) {
|
|
error_report("rdma_accept returns %d", ret);
|
|
goto err_rdma_dest_wait;
|
|
}
|
|
|
|
ret = rdma_get_cm_event(rdma->channel, &cm_event);
|
|
if (ret) {
|
|
error_report("rdma_accept get_cm_event failed %d", ret);
|
|
goto err_rdma_dest_wait;
|
|
}
|
|
|
|
if (cm_event->event != RDMA_CM_EVENT_ESTABLISHED) {
|
|
error_report("rdma_accept not event established");
|
|
rdma_ack_cm_event(cm_event);
|
|
goto err_rdma_dest_wait;
|
|
}
|
|
|
|
rdma_ack_cm_event(cm_event);
|
|
rdma->connected = true;
|
|
|
|
ret = qemu_rdma_post_recv_control(rdma, RDMA_WRID_READY);
|
|
if (ret) {
|
|
error_report("rdma migration: error posting second control recv");
|
|
goto err_rdma_dest_wait;
|
|
}
|
|
|
|
qemu_rdma_dump_gid("dest_connect", rdma->cm_id);
|
|
|
|
return 0;
|
|
|
|
err_rdma_dest_wait:
|
|
rdma->error_state = ret;
|
|
qemu_rdma_cleanup(rdma);
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* During each iteration of the migration, we listen for instructions
|
|
* by the source VM to perform dynamic page registrations before they
|
|
* can perform RDMA operations.
|
|
*
|
|
* We respond with the 'rkey'.
|
|
*
|
|
* Keep doing this until the source tells us to stop.
|
|
*/
|
|
static int qemu_rdma_registration_handle(QEMUFile *f, void *opaque,
|
|
uint64_t flags)
|
|
{
|
|
RDMAControlHeader reg_resp = { .len = sizeof(RDMARegisterResult),
|
|
.type = RDMA_CONTROL_REGISTER_RESULT,
|
|
.repeat = 0,
|
|
};
|
|
RDMAControlHeader unreg_resp = { .len = 0,
|
|
.type = RDMA_CONTROL_UNREGISTER_FINISHED,
|
|
.repeat = 0,
|
|
};
|
|
RDMAControlHeader blocks = { .type = RDMA_CONTROL_RAM_BLOCKS_RESULT,
|
|
.repeat = 1 };
|
|
QEMUFileRDMA *rfile = opaque;
|
|
RDMAContext *rdma = rfile->rdma;
|
|
RDMALocalBlocks *local = &rdma->local_ram_blocks;
|
|
RDMAControlHeader head;
|
|
RDMARegister *reg, *registers;
|
|
RDMACompress *comp;
|
|
RDMARegisterResult *reg_result;
|
|
static RDMARegisterResult results[RDMA_CONTROL_MAX_COMMANDS_PER_MESSAGE];
|
|
RDMALocalBlock *block;
|
|
void *host_addr;
|
|
int ret = 0;
|
|
int idx = 0;
|
|
int count = 0;
|
|
int i = 0;
|
|
|
|
CHECK_ERROR_STATE();
|
|
|
|
do {
|
|
trace_qemu_rdma_registration_handle_wait(flags);
|
|
|
|
ret = qemu_rdma_exchange_recv(rdma, &head, RDMA_CONTROL_NONE);
|
|
|
|
if (ret < 0) {
|
|
break;
|
|
}
|
|
|
|
if (head.repeat > RDMA_CONTROL_MAX_COMMANDS_PER_MESSAGE) {
|
|
error_report("rdma: Too many requests in this message (%d)."
|
|
"Bailing.", head.repeat);
|
|
ret = -EIO;
|
|
break;
|
|
}
|
|
|
|
switch (head.type) {
|
|
case RDMA_CONTROL_COMPRESS:
|
|
comp = (RDMACompress *) rdma->wr_data[idx].control_curr;
|
|
network_to_compress(comp);
|
|
|
|
trace_qemu_rdma_registration_handle_compress(comp->length,
|
|
comp->block_idx,
|
|
comp->offset);
|
|
block = &(rdma->local_ram_blocks.block[comp->block_idx]);
|
|
|
|
host_addr = block->local_host_addr +
|
|
(comp->offset - block->offset);
|
|
|
|
ram_handle_compressed(host_addr, comp->value, comp->length);
|
|
break;
|
|
|
|
case RDMA_CONTROL_REGISTER_FINISHED:
|
|
trace_qemu_rdma_registration_handle_finished();
|
|
goto out;
|
|
|
|
case RDMA_CONTROL_RAM_BLOCKS_REQUEST:
|
|
trace_qemu_rdma_registration_handle_ram_blocks();
|
|
|
|
if (rdma->pin_all) {
|
|
ret = qemu_rdma_reg_whole_ram_blocks(rdma);
|
|
if (ret) {
|
|
error_report("rdma migration: error dest "
|
|
"registering ram blocks");
|
|
goto out;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Dest uses this to prepare to transmit the RAMBlock descriptions
|
|
* to the source VM after connection setup.
|
|
* Both sides use the "remote" structure to communicate and update
|
|
* their "local" descriptions with what was sent.
|
|
*/
|
|
for (i = 0; i < local->nb_blocks; i++) {
|
|
rdma->block[i].remote_host_addr =
|
|
(uintptr_t)(local->block[i].local_host_addr);
|
|
|
|
if (rdma->pin_all) {
|
|
rdma->block[i].remote_rkey = local->block[i].mr->rkey;
|
|
}
|
|
|
|
rdma->block[i].offset = local->block[i].offset;
|
|
rdma->block[i].length = local->block[i].length;
|
|
|
|
remote_block_to_network(&rdma->block[i]);
|
|
}
|
|
|
|
blocks.len = rdma->local_ram_blocks.nb_blocks
|
|
* sizeof(RDMARemoteBlock);
|
|
|
|
|
|
ret = qemu_rdma_post_send_control(rdma,
|
|
(uint8_t *) rdma->block, &blocks);
|
|
|
|
if (ret < 0) {
|
|
error_report("rdma migration: error sending remote info");
|
|
goto out;
|
|
}
|
|
|
|
break;
|
|
case RDMA_CONTROL_REGISTER_REQUEST:
|
|
trace_qemu_rdma_registration_handle_register(head.repeat);
|
|
|
|
reg_resp.repeat = head.repeat;
|
|
registers = (RDMARegister *) rdma->wr_data[idx].control_curr;
|
|
|
|
for (count = 0; count < head.repeat; count++) {
|
|
uint64_t chunk;
|
|
uint8_t *chunk_start, *chunk_end;
|
|
|
|
reg = ®isters[count];
|
|
network_to_register(reg);
|
|
|
|
reg_result = &results[count];
|
|
|
|
trace_qemu_rdma_registration_handle_register_loop(count,
|
|
reg->current_index, reg->key.current_addr, reg->chunks);
|
|
|
|
block = &(rdma->local_ram_blocks.block[reg->current_index]);
|
|
if (block->is_ram_block) {
|
|
host_addr = (block->local_host_addr +
|
|
(reg->key.current_addr - block->offset));
|
|
chunk = ram_chunk_index(block->local_host_addr,
|
|
(uint8_t *) host_addr);
|
|
} else {
|
|
chunk = reg->key.chunk;
|
|
host_addr = block->local_host_addr +
|
|
(reg->key.chunk * (1UL << RDMA_REG_CHUNK_SHIFT));
|
|
}
|
|
chunk_start = ram_chunk_start(block, chunk);
|
|
chunk_end = ram_chunk_end(block, chunk + reg->chunks);
|
|
if (qemu_rdma_register_and_get_keys(rdma, block,
|
|
(uintptr_t)host_addr, NULL, ®_result->rkey,
|
|
chunk, chunk_start, chunk_end)) {
|
|
error_report("cannot get rkey");
|
|
ret = -EINVAL;
|
|
goto out;
|
|
}
|
|
|
|
reg_result->host_addr = (uintptr_t)block->local_host_addr;
|
|
|
|
trace_qemu_rdma_registration_handle_register_rkey(
|
|
reg_result->rkey);
|
|
|
|
result_to_network(reg_result);
|
|
}
|
|
|
|
ret = qemu_rdma_post_send_control(rdma,
|
|
(uint8_t *) results, ®_resp);
|
|
|
|
if (ret < 0) {
|
|
error_report("Failed to send control buffer");
|
|
goto out;
|
|
}
|
|
break;
|
|
case RDMA_CONTROL_UNREGISTER_REQUEST:
|
|
trace_qemu_rdma_registration_handle_unregister(head.repeat);
|
|
unreg_resp.repeat = head.repeat;
|
|
registers = (RDMARegister *) rdma->wr_data[idx].control_curr;
|
|
|
|
for (count = 0; count < head.repeat; count++) {
|
|
reg = ®isters[count];
|
|
network_to_register(reg);
|
|
|
|
trace_qemu_rdma_registration_handle_unregister_loop(count,
|
|
reg->current_index, reg->key.chunk);
|
|
|
|
block = &(rdma->local_ram_blocks.block[reg->current_index]);
|
|
|
|
ret = ibv_dereg_mr(block->pmr[reg->key.chunk]);
|
|
block->pmr[reg->key.chunk] = NULL;
|
|
|
|
if (ret != 0) {
|
|
perror("rdma unregistration chunk failed");
|
|
ret = -ret;
|
|
goto out;
|
|
}
|
|
|
|
rdma->total_registrations--;
|
|
|
|
trace_qemu_rdma_registration_handle_unregister_success(
|
|
reg->key.chunk);
|
|
}
|
|
|
|
ret = qemu_rdma_post_send_control(rdma, NULL, &unreg_resp);
|
|
|
|
if (ret < 0) {
|
|
error_report("Failed to send control buffer");
|
|
goto out;
|
|
}
|
|
break;
|
|
case RDMA_CONTROL_REGISTER_RESULT:
|
|
error_report("Invalid RESULT message at dest.");
|
|
ret = -EIO;
|
|
goto out;
|
|
default:
|
|
error_report("Unknown control message %s", control_desc[head.type]);
|
|
ret = -EIO;
|
|
goto out;
|
|
}
|
|
} while (1);
|
|
out:
|
|
if (ret < 0) {
|
|
rdma->error_state = ret;
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
static int qemu_rdma_registration_start(QEMUFile *f, void *opaque,
|
|
uint64_t flags)
|
|
{
|
|
QEMUFileRDMA *rfile = opaque;
|
|
RDMAContext *rdma = rfile->rdma;
|
|
|
|
CHECK_ERROR_STATE();
|
|
|
|
trace_qemu_rdma_registration_start(flags);
|
|
qemu_put_be64(f, RAM_SAVE_FLAG_HOOK);
|
|
qemu_fflush(f);
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Inform dest that dynamic registrations are done for now.
|
|
* First, flush writes, if any.
|
|
*/
|
|
static int qemu_rdma_registration_stop(QEMUFile *f, void *opaque,
|
|
uint64_t flags)
|
|
{
|
|
Error *local_err = NULL, **errp = &local_err;
|
|
QEMUFileRDMA *rfile = opaque;
|
|
RDMAContext *rdma = rfile->rdma;
|
|
RDMAControlHeader head = { .len = 0, .repeat = 1 };
|
|
int ret = 0;
|
|
|
|
CHECK_ERROR_STATE();
|
|
|
|
qemu_fflush(f);
|
|
ret = qemu_rdma_drain_cq(f, rdma);
|
|
|
|
if (ret < 0) {
|
|
goto err;
|
|
}
|
|
|
|
if (flags == RAM_CONTROL_SETUP) {
|
|
RDMAControlHeader resp = {.type = RDMA_CONTROL_RAM_BLOCKS_RESULT };
|
|
RDMALocalBlocks *local = &rdma->local_ram_blocks;
|
|
int reg_result_idx, i, j, nb_remote_blocks;
|
|
|
|
head.type = RDMA_CONTROL_RAM_BLOCKS_REQUEST;
|
|
trace_qemu_rdma_registration_stop_ram();
|
|
|
|
/*
|
|
* Make sure that we parallelize the pinning on both sides.
|
|
* For very large guests, doing this serially takes a really
|
|
* long time, so we have to 'interleave' the pinning locally
|
|
* with the control messages by performing the pinning on this
|
|
* side before we receive the control response from the other
|
|
* side that the pinning has completed.
|
|
*/
|
|
ret = qemu_rdma_exchange_send(rdma, &head, NULL, &resp,
|
|
®_result_idx, rdma->pin_all ?
|
|
qemu_rdma_reg_whole_ram_blocks : NULL);
|
|
if (ret < 0) {
|
|
ERROR(errp, "receiving remote info!");
|
|
return ret;
|
|
}
|
|
|
|
nb_remote_blocks = resp.len / sizeof(RDMARemoteBlock);
|
|
|
|
/*
|
|
* The protocol uses two different sets of rkeys (mutually exclusive):
|
|
* 1. One key to represent the virtual address of the entire ram block.
|
|
* (dynamic chunk registration disabled - pin everything with one rkey.)
|
|
* 2. One to represent individual chunks within a ram block.
|
|
* (dynamic chunk registration enabled - pin individual chunks.)
|
|
*
|
|
* Once the capability is successfully negotiated, the destination transmits
|
|
* the keys to use (or sends them later) including the virtual addresses
|
|
* and then propagates the remote ram block descriptions to his local copy.
|
|
*/
|
|
|
|
if (local->nb_blocks != nb_remote_blocks) {
|
|
ERROR(errp, "ram blocks mismatch #1! "
|
|
"Your QEMU command line parameters are probably "
|
|
"not identical on both the source and destination.");
|
|
return -EINVAL;
|
|
}
|
|
|
|
qemu_rdma_move_header(rdma, reg_result_idx, &resp);
|
|
memcpy(rdma->block,
|
|
rdma->wr_data[reg_result_idx].control_curr, resp.len);
|
|
for (i = 0; i < nb_remote_blocks; i++) {
|
|
network_to_remote_block(&rdma->block[i]);
|
|
|
|
/* search local ram blocks */
|
|
for (j = 0; j < local->nb_blocks; j++) {
|
|
if (rdma->block[i].offset != local->block[j].offset) {
|
|
continue;
|
|
}
|
|
|
|
if (rdma->block[i].length != local->block[j].length) {
|
|
ERROR(errp, "ram blocks mismatch #2! "
|
|
"Your QEMU command line parameters are probably "
|
|
"not identical on both the source and destination.");
|
|
return -EINVAL;
|
|
}
|
|
local->block[j].remote_host_addr =
|
|
rdma->block[i].remote_host_addr;
|
|
local->block[j].remote_rkey = rdma->block[i].remote_rkey;
|
|
break;
|
|
}
|
|
|
|
if (j >= local->nb_blocks) {
|
|
ERROR(errp, "ram blocks mismatch #3! "
|
|
"Your QEMU command line parameters are probably "
|
|
"not identical on both the source and destination.");
|
|
return -EINVAL;
|
|
}
|
|
}
|
|
}
|
|
|
|
trace_qemu_rdma_registration_stop(flags);
|
|
|
|
head.type = RDMA_CONTROL_REGISTER_FINISHED;
|
|
ret = qemu_rdma_exchange_send(rdma, &head, NULL, NULL, NULL, NULL);
|
|
|
|
if (ret < 0) {
|
|
goto err;
|
|
}
|
|
|
|
return 0;
|
|
err:
|
|
rdma->error_state = ret;
|
|
return ret;
|
|
}
|
|
|
|
static int qemu_rdma_get_fd(void *opaque)
|
|
{
|
|
QEMUFileRDMA *rfile = opaque;
|
|
RDMAContext *rdma = rfile->rdma;
|
|
|
|
return rdma->comp_channel->fd;
|
|
}
|
|
|
|
static const QEMUFileOps rdma_read_ops = {
|
|
.get_buffer = qemu_rdma_get_buffer,
|
|
.get_fd = qemu_rdma_get_fd,
|
|
.close = qemu_rdma_close,
|
|
.hook_ram_load = qemu_rdma_registration_handle,
|
|
};
|
|
|
|
static const QEMUFileOps rdma_write_ops = {
|
|
.put_buffer = qemu_rdma_put_buffer,
|
|
.close = qemu_rdma_close,
|
|
.before_ram_iterate = qemu_rdma_registration_start,
|
|
.after_ram_iterate = qemu_rdma_registration_stop,
|
|
.save_page = qemu_rdma_save_page,
|
|
};
|
|
|
|
static void *qemu_fopen_rdma(RDMAContext *rdma, const char *mode)
|
|
{
|
|
QEMUFileRDMA *r = g_malloc0(sizeof(QEMUFileRDMA));
|
|
|
|
if (qemu_file_mode_is_not_valid(mode)) {
|
|
return NULL;
|
|
}
|
|
|
|
r->rdma = rdma;
|
|
|
|
if (mode[0] == 'w') {
|
|
r->file = qemu_fopen_ops(r, &rdma_write_ops);
|
|
} else {
|
|
r->file = qemu_fopen_ops(r, &rdma_read_ops);
|
|
}
|
|
|
|
return r->file;
|
|
}
|
|
|
|
static void rdma_accept_incoming_migration(void *opaque)
|
|
{
|
|
RDMAContext *rdma = opaque;
|
|
int ret;
|
|
QEMUFile *f;
|
|
Error *local_err = NULL, **errp = &local_err;
|
|
|
|
trace_qemu_dma_accept_incoming_migration();
|
|
ret = qemu_rdma_accept(rdma);
|
|
|
|
if (ret) {
|
|
ERROR(errp, "RDMA Migration initialization failed!");
|
|
return;
|
|
}
|
|
|
|
trace_qemu_dma_accept_incoming_migration_accepted();
|
|
|
|
f = qemu_fopen_rdma(rdma, "rb");
|
|
if (f == NULL) {
|
|
ERROR(errp, "could not qemu_fopen_rdma!");
|
|
qemu_rdma_cleanup(rdma);
|
|
return;
|
|
}
|
|
|
|
rdma->migration_started_on_destination = 1;
|
|
process_incoming_migration(f);
|
|
}
|
|
|
|
void rdma_start_incoming_migration(const char *host_port, Error **errp)
|
|
{
|
|
int ret;
|
|
RDMAContext *rdma;
|
|
Error *local_err = NULL;
|
|
|
|
trace_rdma_start_incoming_migration();
|
|
rdma = qemu_rdma_data_init(host_port, &local_err);
|
|
|
|
if (rdma == NULL) {
|
|
goto err;
|
|
}
|
|
|
|
ret = qemu_rdma_dest_init(rdma, &local_err);
|
|
|
|
if (ret) {
|
|
goto err;
|
|
}
|
|
|
|
trace_rdma_start_incoming_migration_after_dest_init();
|
|
|
|
ret = rdma_listen(rdma->listen_id, 5);
|
|
|
|
if (ret) {
|
|
ERROR(errp, "listening on socket!");
|
|
goto err;
|
|
}
|
|
|
|
trace_rdma_start_incoming_migration_after_rdma_listen();
|
|
|
|
qemu_set_fd_handler2(rdma->channel->fd, NULL,
|
|
rdma_accept_incoming_migration, NULL,
|
|
(void *)(intptr_t) rdma);
|
|
return;
|
|
err:
|
|
error_propagate(errp, local_err);
|
|
g_free(rdma);
|
|
}
|
|
|
|
void rdma_start_outgoing_migration(void *opaque,
|
|
const char *host_port, Error **errp)
|
|
{
|
|
MigrationState *s = opaque;
|
|
Error *local_err = NULL, **temp = &local_err;
|
|
RDMAContext *rdma = qemu_rdma_data_init(host_port, &local_err);
|
|
int ret = 0;
|
|
|
|
if (rdma == NULL) {
|
|
ERROR(temp, "Failed to initialize RDMA data structures! %d", ret);
|
|
goto err;
|
|
}
|
|
|
|
ret = qemu_rdma_source_init(rdma, &local_err,
|
|
s->enabled_capabilities[MIGRATION_CAPABILITY_RDMA_PIN_ALL]);
|
|
|
|
if (ret) {
|
|
goto err;
|
|
}
|
|
|
|
trace_rdma_start_outgoing_migration_after_rdma_source_init();
|
|
ret = qemu_rdma_connect(rdma, &local_err);
|
|
|
|
if (ret) {
|
|
goto err;
|
|
}
|
|
|
|
trace_rdma_start_outgoing_migration_after_rdma_connect();
|
|
|
|
s->file = qemu_fopen_rdma(rdma, "wb");
|
|
migrate_fd_connect(s);
|
|
return;
|
|
err:
|
|
error_propagate(errp, local_err);
|
|
g_free(rdma);
|
|
migrate_fd_error(s);
|
|
}
|