 dd286ed700
			
		
	
	
		dd286ed700
		
	
	
	
	
		
			
			Signed-off-by: Isaku Yamahata <yamahata@private.email.ne.jp> Signed-off-by: Juan Quintela <quintela@redhat.com>
		
			
				
	
	
		
			3438 lines
		
	
	
		
			105 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			3438 lines
		
	
	
		
			105 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
 | |
|  * RDMA protocol and interfaces
 | |
|  *
 | |
|  * Copyright IBM, Corp. 2010-2013
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|  *
 | |
|  * Authors:
 | |
|  *  Michael R. Hines <mrhines@us.ibm.com>
 | |
|  *  Jiuxing Liu <jl@us.ibm.com>
 | |
|  *
 | |
|  * This work is licensed under the terms of the GNU GPL, version 2 or
 | |
|  * later.  See the COPYING file in the top-level directory.
 | |
|  *
 | |
|  */
 | |
| #include "qemu-common.h"
 | |
| #include "migration/migration.h"
 | |
| #include "migration/qemu-file.h"
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| #include "exec/cpu-common.h"
 | |
| #include "qemu/main-loop.h"
 | |
| #include "qemu/sockets.h"
 | |
| #include "qemu/bitmap.h"
 | |
| #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>
 | |
| #include <arpa/inet.h>
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| #include <string.h>
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| #include <rdma/rdma_cma.h>
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| 
 | |
| //#define DEBUG_RDMA
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| //#define DEBUG_RDMA_VERBOSE
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| //#define DEBUG_RDMA_REALLY_VERBOSE
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| 
 | |
| #ifdef DEBUG_RDMA
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| #define DPRINTF(fmt, ...) \
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|     do { printf("rdma: " fmt, ## __VA_ARGS__); } while (0)
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| #else
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| #define DPRINTF(fmt, ...) \
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|     do { } while (0)
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| #endif
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| 
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| #ifdef DEBUG_RDMA_VERBOSE
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| #define DDPRINTF(fmt, ...) \
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|     do { printf("rdma: " fmt, ## __VA_ARGS__); } while (0)
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| #else
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| #define DDPRINTF(fmt, ...) \
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|     do { } while (0)
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| #endif
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| 
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| #ifdef DEBUG_RDMA_REALLY_VERBOSE
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| #define DDDPRINTF(fmt, ...) \
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|     do { printf("rdma: " fmt, ## __VA_ARGS__); } while (0)
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| #else
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| #define DDDPRINTF(fmt, ...) \
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|     do { } while (0)
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| #endif
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| 
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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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| 
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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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| 
 | |
| /*
 | |
|  * This is only for non-live state being migrated.
 | |
|  * 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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|  */
 | |
| #define RDMA_SEND_INCREMENT 32768
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| 
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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)
 | |
| #define RDMA_CONTROL_MAX_COMMANDS_PER_MESSAGE 4096
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| 
 | |
| #define RDMA_CONTROL_VERSION_CURRENT 1
 | |
| /*
 | |
|  * Capabilities for negotiation.
 | |
|  */
 | |
| #define RDMA_CAPABILITY_PIN_ALL 0x01
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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() \
 | |
|     do { \
 | |
|         if (rdma->error_state) { \
 | |
|             if (!rdma->error_reported) { \
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|                 fprintf(stderr, "RDMA is in an error state waiting migration" \
 | |
|                                 " to abort!\n"); \
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|                 rdma->error_reported = 1; \
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|             } \
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|             return rdma->error_state; \
 | |
|         } \
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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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|  */
 | |
| #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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| 
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| #define RDMA_WRID_TYPE_MASK \
 | |
|     ((1UL << RDMA_WRID_BLOCK_SHIFT) - 1UL)
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| 
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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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| 
 | |
| /*
 | |
|  * RDMA migration protocol:
 | |
|  * 1. RDMA Writes (data messages, i.e. RAM)
 | |
|  * 2. IB Send/Recv (control channel messages)
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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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| 
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| 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).
 | |
|  * 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.
 | |
|  */
 | |
| enum {
 | |
|     RDMA_CONTROL_NONE = 0,
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|     RDMA_CONTROL_ERROR,
 | |
|     RDMA_CONTROL_READY,               /* ready to receive */
 | |
|     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 */
 | |
|     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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| 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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|  * 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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| /*
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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;
 | |
| } 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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| 
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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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| /*
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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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| /*
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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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| 
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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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| 
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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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| 
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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);
 | |
| }
 | |
| 
 | |
| /*
 | |
|  * Virtual address of the above structures used for transmitting
 | |
|  * the RAMBlock descriptions at connection-time.
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|  * This structure is *not* transmitted.
 | |
|  */
 | |
| 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;
 | |
| } RDMALocalBlocks;
 | |
| 
 | |
| /*
 | |
|  * Main data structure for RDMA state.
 | |
|  * 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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|  */
 | |
| 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
 | |
|      * the initial "READY" message has already been received or not.
 | |
|      * This is because other functions may potentially poll() and detect
 | |
|      * the READY message before send() does, in which case we need to
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|      * know if it completed.
 | |
|      */
 | |
|     int control_ready_expected;
 | |
| 
 | |
|     /* number of outstanding writes */
 | |
|     int nb_sent;
 | |
| 
 | |
|     /* store info about current buffer so that we can
 | |
|        merge it with future sends */
 | |
|     uint64_t current_addr;
 | |
|     uint64_t current_length;
 | |
|     /* index of ram block the current buffer belongs to */
 | |
|     int current_index;
 | |
|     /* index of the chunk in the current ram block */
 | |
|     int current_chunk;
 | |
| 
 | |
|     bool pin_all;
 | |
| 
 | |
|     /*
 | |
|      * infiniband-specific variables for opening the device
 | |
|      * 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.
 | |
|      */
 | |
|     struct rdma_cm_id *cm_id;               /* connection manager ID */
 | |
|     struct rdma_cm_id *listen_id;
 | |
|     bool connected;
 | |
| 
 | |
|     struct ibv_context          *verbs;
 | |
|     struct rdma_event_channel   *channel;
 | |
|     struct ibv_qp *qp;                      /* queue pair */
 | |
|     struct ibv_comp_channel *comp_channel;  /* completion channel */
 | |
|     struct ibv_pd *pd;                      /* protection domain */
 | |
|     struct ibv_cq *cq;                      /* completion queue */
 | |
| 
 | |
|     /*
 | |
|      * If a previous write failed (perhaps because of a failed
 | |
|      * memory registration, then do not attempt any future work
 | |
|      * and remember the error state.
 | |
|      */
 | |
|     int error_state;
 | |
|     int error_reported;
 | |
| 
 | |
|     /*
 | |
|      * Description of ram blocks used throughout the code.
 | |
|      */
 | |
|     RDMALocalBlocks local_ram_blocks;
 | |
|     RDMARemoteBlock *block;
 | |
| 
 | |
|     /*
 | |
|      * Migration on *destination* started.
 | |
|      * Then use coroutine yield function.
 | |
|      * Source runs in a thread, so we don't care.
 | |
|      */
 | |
|     int migration_started_on_destination;
 | |
| 
 | |
|     int total_registrations;
 | |
|     int total_writes;
 | |
| 
 | |
|     int unregister_current, unregister_next;
 | |
|     uint64_t unregistrations[RDMA_SIGNALED_SEND_MAX];
 | |
| 
 | |
|     GHashTable *blockmap;
 | |
| } RDMAContext;
 | |
| 
 | |
| /*
 | |
|  * Interface to the rest of the migration call stack.
 | |
|  */
 | |
| typedef struct QEMUFileRDMA {
 | |
|     RDMAContext *rdma;
 | |
|     size_t len;
 | |
|     void *file;
 | |
| } QEMUFileRDMA;
 | |
| 
 | |
| /*
 | |
|  * Main structure for IB Send/Recv control messages.
 | |
|  * This gets prepended at the beginning of every Send/Recv.
 | |
|  */
 | |
| typedef struct QEMU_PACKED {
 | |
|     uint32_t len;     /* Total length of data portion */
 | |
|     uint32_t type;    /* which control command to perform */
 | |
|     uint32_t repeat;  /* number of commands in data portion of same type */
 | |
|     uint32_t padding;
 | |
| } RDMAControlHeader;
 | |
| 
 | |
| static void control_to_network(RDMAControlHeader *control)
 | |
| {
 | |
|     control->type = htonl(control->type);
 | |
|     control->len = htonl(control->len);
 | |
|     control->repeat = htonl(control->repeat);
 | |
| }
 | |
| 
 | |
| static void network_to_control(RDMAControlHeader *control)
 | |
| {
 | |
|     control->type = ntohl(control->type);
 | |
|     control->len = ntohl(control->len);
 | |
|     control->repeat = ntohl(control->repeat);
 | |
| }
 | |
| 
 | |
| /*
 | |
|  * Register a single Chunk.
 | |
|  * Information sent by the source VM to inform the dest
 | |
|  * to register an single chunk of memory before we can perform
 | |
|  * the actual RDMA operation.
 | |
|  */
 | |
| typedef struct QEMU_PACKED {
 | |
|     union QEMU_PACKED {
 | |
|         uint64_t current_addr;  /* offset into the ramblock of the chunk */
 | |
|         uint64_t chunk;         /* chunk to lookup if unregistering */
 | |
|     } key;
 | |
|     uint32_t current_index; /* which ramblock the chunk belongs to */
 | |
|     uint32_t padding;
 | |
|     uint64_t chunks;            /* how many sequential chunks to register */
 | |
| } RDMARegister;
 | |
| 
 | |
| static void register_to_network(RDMARegister *reg)
 | |
| {
 | |
|     reg->key.current_addr = htonll(reg->key.current_addr);
 | |
|     reg->current_index = htonl(reg->current_index);
 | |
|     reg->chunks = htonll(reg->chunks);
 | |
| }
 | |
| 
 | |
| static void network_to_register(RDMARegister *reg)
 | |
| {
 | |
|     reg->key.current_addr = ntohll(reg->key.current_addr);
 | |
|     reg->current_index = ntohl(reg->current_index);
 | |
|     reg->chunks = ntohll(reg->chunks);
 | |
| }
 | |
| 
 | |
| typedef struct QEMU_PACKED {
 | |
|     uint32_t value;     /* if zero, we will madvise() */
 | |
|     uint32_t block_idx; /* which ram block index */
 | |
|     uint64_t offset;    /* where in the remote ramblock this chunk */
 | |
|     uint64_t length;    /* length of the chunk */
 | |
| } RDMACompress;
 | |
| 
 | |
| static void compress_to_network(RDMACompress *comp)
 | |
| {
 | |
|     comp->value = htonl(comp->value);
 | |
|     comp->block_idx = htonl(comp->block_idx);
 | |
|     comp->offset = htonll(comp->offset);
 | |
|     comp->length = htonll(comp->length);
 | |
| }
 | |
| 
 | |
| static void network_to_compress(RDMACompress *comp)
 | |
| {
 | |
|     comp->value = ntohl(comp->value);
 | |
|     comp->block_idx = ntohl(comp->block_idx);
 | |
|     comp->offset = ntohll(comp->offset);
 | |
|     comp->length = ntohll(comp->length);
 | |
| }
 | |
| 
 | |
| /*
 | |
|  * The result of the dest's memory registration produces an "rkey"
 | |
|  * which the source VM must reference in order to perform
 | |
|  * the RDMA operation.
 | |
|  */
 | |
| typedef struct QEMU_PACKED {
 | |
|     uint32_t rkey;
 | |
|     uint32_t padding;
 | |
|     uint64_t host_addr;
 | |
| } RDMARegisterResult;
 | |
| 
 | |
| static void result_to_network(RDMARegisterResult *result)
 | |
| {
 | |
|     result->rkey = htonl(result->rkey);
 | |
|     result->host_addr = htonll(result->host_addr);
 | |
| };
 | |
| 
 | |
| static void network_to_result(RDMARegisterResult *result)
 | |
| {
 | |
|     result->rkey = ntohl(result->rkey);
 | |
|     result->host_addr = ntohll(result->host_addr);
 | |
| };
 | |
| 
 | |
| const char *print_wrid(int wrid);
 | |
| static int qemu_rdma_exchange_send(RDMAContext *rdma, RDMAControlHeader *head,
 | |
|                                    uint8_t *data, RDMAControlHeader *resp,
 | |
|                                    int *resp_idx,
 | |
|                                    int (*callback)(RDMAContext *rdma));
 | |
| 
 | |
| static inline uint64_t ram_chunk_index(const uint8_t *start,
 | |
|                                        const uint8_t *host)
 | |
| {
 | |
|     return ((uintptr_t) host - (uintptr_t) start) >> RDMA_REG_CHUNK_SHIFT;
 | |
| }
 | |
| 
 | |
| static inline uint8_t *ram_chunk_start(const RDMALocalBlock *rdma_ram_block,
 | |
|                                        uint64_t i)
 | |
| {
 | |
|     return (uint8_t *) (((uintptr_t) rdma_ram_block->local_host_addr)
 | |
|                                     + (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 __qemu_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 *) 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 *)old[x].offset);
 | |
|             g_hash_table_insert(rdma->blockmap, (void *)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);
 | |
| 
 | |
|     DDPRINTF("Added Block: %d, addr: %" PRIu64 ", offset: %" PRIu64
 | |
|            " length: %" PRIu64 " end: %" PRIu64 " bits %" PRIu64 " chunks %d\n",
 | |
|             local->nb_blocks, (uint64_t) block->local_host_addr, block->offset,
 | |
|             block->length, (uint64_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)
 | |
| {
 | |
|     __qemu_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);
 | |
|     DPRINTF("Allocated %d local ram block structures\n", local->nb_blocks);
 | |
|     rdma->block = (RDMARemoteBlock *) g_malloc0(sizeof(RDMARemoteBlock) *
 | |
|                         rdma->local_ram_blocks.nb_blocks);
 | |
|     local->init = true;
 | |
|     return 0;
 | |
| }
 | |
| 
 | |
| static int __qemu_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 *)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;
 | |
|     }
 | |
| 
 | |
|     DDPRINTF("Deleted Block: %d, addr: %" PRIu64 ", offset: %" PRIu64
 | |
|            " length: %" PRIu64 " end: %" PRIu64 " bits %" PRIu64 " chunks %d\n",
 | |
|             local->nb_blocks, (uint64_t) block->local_host_addr, block->offset,
 | |
|             block->length, (uint64_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 *)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)) {
 | |
|         fprintf(stderr, "FAILED TO QUERY PORT INFORMATION!\n");
 | |
|         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);
 | |
|     DPRINTF("%s Source GID: %s, Dest GID: %s\n", 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 potential 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);
 | |
|         DPRINTF("Trying %s => %s\n", 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");
 | |
|         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) {
 | |
|         fprintf(stderr, "failed to allocate protection domain\n");
 | |
|         return -1;
 | |
|     }
 | |
| 
 | |
|     /* create completion channel */
 | |
|     rdma->comp_channel = ibv_create_comp_channel(rdma->verbs);
 | |
|     if (!rdma->comp_channel) {
 | |
|         fprintf(stderr, "failed to allocate completion channel\n");
 | |
|         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) {
 | |
|         fprintf(stderr, "failed to allocate completion queue\n");
 | |
|         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,
 | |
|                                       uint64_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, uint8_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 (!block->pmr) {
 | |
|             return -1;
 | |
|         }
 | |
|     }
 | |
| 
 | |
|     /*
 | |
|      * 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;
 | |
| 
 | |
|         DDPRINTF("Registering %" PRIu64 " bytes @ %p\n",
 | |
|                  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 %" PRIu64 " end %" PRIu64 " host %" PRIu64
 | |
|                             " local %" PRIu64 " registrations: %d\n",
 | |
|                             block->index, chunk, (uint64_t) chunk_start,
 | |
|                             (uint64_t) chunk_end, (uint64_t) host_addr,
 | |
|                             (uint64_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;
 | |
|     }
 | |
|     fprintf(stderr, "qemu_rdma_reg_control failed!\n");
 | |
|     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,
 | |
|                                  };
 | |
| 
 | |
|         DDPRINTF("Processing unregister for chunk: %" PRIu64
 | |
|                  " at position %d\n", 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)) {
 | |
|             DDPRINTF("Cannot unregister inflight chunk: %" PRIu64 "\n", chunk);
 | |
|             continue;
 | |
|         }
 | |
| 
 | |
|         DDPRINTF("Sending unregister for chunk: %" PRIu64 "\n", 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;
 | |
|         }
 | |
| 
 | |
|         DDPRINTF("Unregister for chunk: %" PRIu64 " complete.\n", 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) {
 | |
|         fprintf(stderr, "rdma migration: queue is full!\n");
 | |
|     } else {
 | |
|         RDMALocalBlock *block = &(rdma->local_ram_blocks.block[index]);
 | |
| 
 | |
|         if (!test_and_set_bit(chunk, block->unregister_bitmap)) {
 | |
|             DDPRINTF("Appending unregister chunk %" PRIu64
 | |
|                     " at position %d\n", 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 {
 | |
|             DDPRINTF("Unregister chunk %" PRIu64 " already in queue.\n",
 | |
|                     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) {
 | |
|         fprintf(stderr, "ibv_poll_cq return %d!\n", 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)) {
 | |
|         DDDPRINTF("completion %s #%" PRId64 " received (%" PRId64 ")"
 | |
|                   " left %d\n", 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]);
 | |
| 
 | |
|         DDDPRINTF("completions %s (%" PRId64 ") left %d, "
 | |
|                  "block %" PRIu64 ", chunk: %" PRIu64 " %p %p\n",
 | |
|                  print_wrid(wr_id), wr_id, rdma->nb_sent, index, chunk,
 | |
|                  block->local_host_addr, (void *)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 {
 | |
|         DDDPRINTF("other completion %s (%" PRId64 ") received left %d\n",
 | |
|             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) {
 | |
|             DDDPRINTF("A Wanted wrid %s (%d) but got %s (%" PRIu64 ")\n",
 | |
|                 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) {
 | |
|                 DDDPRINTF("B Wanted wrid %s (%d) but got %s (%" PRIu64 ")\n",
 | |
|                     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 = (uint64_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,
 | |
|                                 };
 | |
| 
 | |
|     DDDPRINTF("CONTROL: sending %s..\n", 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);
 | |
|     }
 | |
| 
 | |
| 
 | |
|     if (ibv_post_send(rdma->qp, &send_wr, &bad_wr)) {
 | |
|         return -1;
 | |
|     }
 | |
| 
 | |
|     if (ret < 0) {
 | |
|         fprintf(stderr, "Failed to use post IB SEND for control!\n");
 | |
|         return ret;
 | |
|     }
 | |
| 
 | |
|     ret = qemu_rdma_block_for_wrid(rdma, RDMA_WRID_SEND_CONTROL, NULL);
 | |
|     if (ret < 0) {
 | |
|         fprintf(stderr, "rdma migration: send polling control error!\n");
 | |
|     }
 | |
| 
 | |
|     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 = (uint64_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) {
 | |
|         fprintf(stderr, "rdma migration: recv polling control error!\n");
 | |
|         return ret;
 | |
|     }
 | |
| 
 | |
|     network_to_control((void *) rdma->wr_data[idx].control);
 | |
|     memcpy(head, rdma->wr_data[idx].control, sizeof(RDMAControlHeader));
 | |
| 
 | |
|     DDDPRINTF("CONTROL: %s receiving...\n", control_desc[expecting]);
 | |
| 
 | |
|     if (expecting == RDMA_CONTROL_NONE) {
 | |
|         DDDPRINTF("Surprise: got %s (%d)\n",
 | |
|                   control_desc[head->type], head->type);
 | |
|     } else if (head->type != expecting || head->type == RDMA_CONTROL_ERROR) {
 | |
|         fprintf(stderr, "Was expecting a %s (%d) control message"
 | |
|                 ", but got: %s (%d), length: %d\n",
 | |
|                 control_desc[expecting], expecting,
 | |
|                 control_desc[head->type], head->type, head->len);
 | |
|         return -EIO;
 | |
|     }
 | |
|     if (head->len > RDMA_CONTROL_MAX_BUFFER - sizeof(*head)) {
 | |
|         fprintf(stderr, "too long length: %d\n", head->len);
 | |
|         return -EINVAL;
 | |
|     }
 | |
|     if (sizeof(*head) + head->len != byte_len) {
 | |
|         fprintf(stderr, "Malformed length: %d byte_len %d\n",
 | |
|                 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) {
 | |
|             fprintf(stderr, "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) {
 | |
|         fprintf(stderr, "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) {
 | |
|         fprintf(stderr, "Failed to send control buffer!\n");
 | |
|         return ret;
 | |
|     }
 | |
| 
 | |
|     /*
 | |
|      * If we're expecting a response, block and wait for it.
 | |
|      */
 | |
|     if (resp) {
 | |
|         if (callback) {
 | |
|             DDPRINTF("Issuing callback before receiving response...\n");
 | |
|             ret = callback(rdma);
 | |
|             if (ret < 0) {
 | |
|                 return ret;
 | |
|             }
 | |
|         }
 | |
| 
 | |
|         DDPRINTF("Waiting for response %s\n", 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;
 | |
|         }
 | |
|         DDPRINTF("Response %s received.\n", 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) {
 | |
|         fprintf(stderr, "Failed to send control buffer!\n");
 | |
|         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) {
 | |
|         fprintf(stderr, "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 = (uint64_t)(block->local_host_addr +
 | |
|                             (current_addr - block->offset));
 | |
|     sge.length = length;
 | |
| 
 | |
|     chunk = ram_chunk_index(block->local_host_addr, (uint8_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--;
 | |
|         }
 | |
|     }
 | |
| 
 | |
|     DDPRINTF("Writing %" PRIu64 " chunks, (%" PRIu64 " MB)\n",
 | |
|         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;
 | |
|         DDPRINTF("(%d) Not clobbering: block: %d chunk %" PRIu64
 | |
|                 " current %" PRIu64 " len %" PRIu64 " %d %d\n",
 | |
|                 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) {
 | |
|             fprintf(stderr, "Failed to Wait for previous write to complete "
 | |
|                     "block %d chunk %" PRIu64
 | |
|                     " current %" PRIu64 " len %" PRIu64 " %d\n",
 | |
|                     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 *)sge.addr, length)
 | |
|                    && buffer_find_nonzero_offset((void *)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;
 | |
| 
 | |
|                 DDPRINTF("Entire chunk is zero, sending compress: %"
 | |
|                     PRIu64 " for %d "
 | |
|                     "bytes, index: %d, offset: %" PRId64 "...\n",
 | |
|                     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;
 | |
| 
 | |
|             DDPRINTF("Sending registration request chunk %" PRIu64 " for %d "
 | |
|                     "bytes, index: %d, offset: %" PRId64 "...\n",
 | |
|                     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,
 | |
|                                                 (uint8_t *) sge.addr,
 | |
|                                                 &sge.lkey, NULL, chunk,
 | |
|                                                 chunk_start, chunk_end)) {
 | |
|                 fprintf(stderr, "cannot get lkey!\n");
 | |
|                 return -EINVAL;
 | |
|             }
 | |
| 
 | |
|             reg_result = (RDMARegisterResult *)
 | |
|                     rdma->wr_data[reg_result_idx].control_curr;
 | |
| 
 | |
|             network_to_result(reg_result);
 | |
| 
 | |
|             DDPRINTF("Received registration result:"
 | |
|                     " my key: %x their key %x, chunk %" PRIu64 "\n",
 | |
|                     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,
 | |
|                                                 (uint8_t *)sge.addr,
 | |
|                                                 &sge.lkey, NULL, chunk,
 | |
|                                                 chunk_start, chunk_end)) {
 | |
|                 fprintf(stderr, "cannot get lkey!\n");
 | |
|                 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, (uint8_t *)sge.addr,
 | |
|                                                      &sge.lkey, NULL, chunk,
 | |
|                                                      chunk_start, chunk_end)) {
 | |
|             fprintf(stderr, "cannot get lkey!\n");
 | |
|             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);
 | |
| 
 | |
|     DDDPRINTF("Posting chunk: %" PRIu64 ", addr: %lx"
 | |
|               " remote: %lx, bytes %" PRIu32 "\n",
 | |
|               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) {
 | |
|         DDPRINTF("send queue is full. wait a little....\n");
 | |
|         ret = qemu_rdma_block_for_wrid(rdma, RDMA_WRID_RDMA_WRITE, NULL);
 | |
|         if (ret < 0) {
 | |
|             fprintf(stderr, "rdma migration: failed to make "
 | |
|                             "room in full send queue! %d\n", 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++;
 | |
|         DDDPRINTF("sent total: %d\n", 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) {
 | |
|             fprintf(stderr, "ram block search failed\n");
 | |
|             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,
 | |
|                                      };
 | |
|             fprintf(stderr, "Early error. Sending error.\n");
 | |
|             qemu_rdma_post_send_control(rdma, NULL, &head);
 | |
|         }
 | |
| 
 | |
|         ret = rdma_disconnect(rdma->cm_id);
 | |
|         if (!ret) {
 | |
|             DDPRINTF("waiting for disconnect\n");
 | |
|             ret = rdma_get_cm_event(rdma->channel, &cm_event);
 | |
|             if (!ret) {
 | |
|                 rdma_ack_cm_event(cm_event);
 | |
|             }
 | |
|         }
 | |
|         DDPRINTF("Disconnected.\n");
 | |
|         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) {
 | |
|             __qemu_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->listen_id) {
 | |
|         rdma_destroy_id(rdma->listen_id);
 | |
|         rdma->listen_id = NULL;
 | |
|     }
 | |
|     if (rdma->cm_id) {
 | |
|         rdma_destroy_id(rdma->cm_id);
 | |
|         rdma->cm_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) {
 | |
|         DPRINTF("Server pin-all memory requested.\n");
 | |
|         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!");
 | |
|         rdma_destroy_id(rdma->cm_id);
 | |
|         rdma->cm_id = NULL;
 | |
|         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);
 | |
|         rdma_destroy_id(rdma->cm_id);
 | |
|         rdma->cm_id = NULL;
 | |
|         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);
 | |
|         rdma_destroy_id(rdma->cm_id);
 | |
|         rdma->cm_id = NULL;
 | |
|         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;
 | |
|     }
 | |
| 
 | |
|     DPRINTF("Pin all memory: %s\n", rdma->pin_all ? "enabled" : "disabled");
 | |
| 
 | |
|     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 = -EINVAL, idx;
 | |
|     struct rdma_cm_id *listen_id;
 | |
|     char ip[40] = "unknown";
 | |
|     struct rdma_addrinfo *res;
 | |
|     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 == NULL) {
 | |
|         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';
 | |
| 
 | |
|     if (rdma->host && strcmp("", rdma->host)) {
 | |
|         struct rdma_addrinfo *e;
 | |
| 
 | |
|         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);
 | |
|             DPRINTF("Trying %s => %s\n", rdma->host, ip);
 | |
|             ret = rdma_bind_addr(listen_id, e->ai_dst_addr);
 | |
|             if (!ret) {
 | |
|                 if (e->ai_family == AF_INET6) {
 | |
|                     ret = qemu_rdma_broken_ipv6_kernel(errp, listen_id->verbs);
 | |
|                     if (ret) {
 | |
|                         continue;
 | |
|                     }
 | |
|                 }
 | |
|                     
 | |
|                 goto listen;
 | |
|             }
 | |
|         }
 | |
| 
 | |
|         ERROR(errp, "Error: could not rdma_bind_addr!");
 | |
|         goto err_dest_init_bind_addr;
 | |
|     } else {
 | |
|         ERROR(errp, "migration host and port not specified!");
 | |
|         ret = -EINVAL;
 | |
|         goto err_dest_init_bind_addr;
 | |
|     }
 | |
| listen:
 | |
| 
 | |
|     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);
 | |
|             return NULL;
 | |
|         }
 | |
|     }
 | |
| 
 | |
|     return rdma;
 | |
| }
 | |
| 
 | |
| /*
 | |
|  * QEMUFile interface to the control channel.
 | |
|  * SEND messages for control only.
 | |
|  * pc.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 pc.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) {
 | |
|         DDDPRINTF("RDMA %" PRId64 " of %d bytes already in buffer\n",
 | |
|                     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) {
 | |
|             fprintf(stderr, "rdma migration: complete polling error!\n");
 | |
|             return -EIO;
 | |
|         }
 | |
|     }
 | |
| 
 | |
|     qemu_rdma_unregister_waiting(rdma);
 | |
| 
 | |
|     return 0;
 | |
| }
 | |
| 
 | |
| static int qemu_rdma_close(void *opaque)
 | |
| {
 | |
|     DPRINTF("Shutting down connection.\n");
 | |
|     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, int *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) {
 | |
|             fprintf(stderr, "rdma migration: write error! %d\n", 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) {
 | |
|             fprintf(stderr, "ram block search failed\n");
 | |
|             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) {
 | |
|             fprintf(stderr, "rdma migration: polling error! %d\n", 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) {
 | |
|             fprintf(stderr, "Unknown source RDMA version: %d, bailing...\n",
 | |
|                             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);
 | |
| 
 | |
|     DPRINTF("Memory pin all: %s\n", rdma->pin_all ? "enabled" : "disabled");
 | |
| 
 | |
|     caps_to_network(&cap);
 | |
| 
 | |
|     DPRINTF("verbs context after listen: %p\n", verbs);
 | |
| 
 | |
|     if (!rdma->verbs) {
 | |
|         rdma->verbs = verbs;
 | |
|     } else if (rdma->verbs != verbs) {
 | |
|             fprintf(stderr, "ibv context not matching %p, %p!\n",
 | |
|                     rdma->verbs, verbs);
 | |
|             goto err_rdma_dest_wait;
 | |
|     }
 | |
| 
 | |
|     qemu_rdma_dump_id("dest_init", verbs);
 | |
| 
 | |
|     ret = qemu_rdma_alloc_pd_cq(rdma);
 | |
|     if (ret) {
 | |
|         fprintf(stderr, "rdma migration: error allocating pd and cq!\n");
 | |
|         goto err_rdma_dest_wait;
 | |
|     }
 | |
| 
 | |
|     ret = qemu_rdma_alloc_qp(rdma);
 | |
|     if (ret) {
 | |
|         fprintf(stderr, "rdma migration: error allocating qp!\n");
 | |
|         goto err_rdma_dest_wait;
 | |
|     }
 | |
| 
 | |
|     ret = qemu_rdma_init_ram_blocks(rdma);
 | |
|     if (ret) {
 | |
|         fprintf(stderr, "rdma migration: error initializing ram blocks!\n");
 | |
|         goto err_rdma_dest_wait;
 | |
|     }
 | |
| 
 | |
|     for (idx = 0; idx < RDMA_WRID_MAX; idx++) {
 | |
|         ret = qemu_rdma_reg_control(rdma, idx);
 | |
|         if (ret) {
 | |
|             fprintf(stderr, "rdma: error registering %d control!\n", 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) {
 | |
|         fprintf(stderr, "rdma_accept returns %d!\n", ret);
 | |
|         goto err_rdma_dest_wait;
 | |
|     }
 | |
| 
 | |
|     ret = rdma_get_cm_event(rdma->channel, &cm_event);
 | |
|     if (ret) {
 | |
|         fprintf(stderr, "rdma_accept get_cm_event failed %d!\n", ret);
 | |
|         goto err_rdma_dest_wait;
 | |
|     }
 | |
| 
 | |
|     if (cm_event->event != RDMA_CM_EVENT_ESTABLISHED) {
 | |
|         fprintf(stderr, "rdma_accept not event established!\n");
 | |
|         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) {
 | |
|         fprintf(stderr, "rdma migration: error posting second control recv!\n");
 | |
|         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 {
 | |
|         DDDPRINTF("Waiting for next request %" PRIu64 "...\n", flags);
 | |
| 
 | |
|         ret = qemu_rdma_exchange_recv(rdma, &head, RDMA_CONTROL_NONE);
 | |
| 
 | |
|         if (ret < 0) {
 | |
|             break;
 | |
|         }
 | |
| 
 | |
|         if (head.repeat > RDMA_CONTROL_MAX_COMMANDS_PER_MESSAGE) {
 | |
|             fprintf(stderr, "rdma: Too many requests in this message (%d)."
 | |
|                             "Bailing.\n", head.repeat);
 | |
|             ret = -EIO;
 | |
|             break;
 | |
|         }
 | |
| 
 | |
|         switch (head.type) {
 | |
|         case RDMA_CONTROL_COMPRESS:
 | |
|             comp = (RDMACompress *) rdma->wr_data[idx].control_curr;
 | |
|             network_to_compress(comp);
 | |
| 
 | |
|             DDPRINTF("Zapping zero chunk: %" PRId64
 | |
|                     " bytes, index %d, offset %" PRId64 "\n",
 | |
|                     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:
 | |
|             DDDPRINTF("Current registrations complete.\n");
 | |
|             goto out;
 | |
| 
 | |
|         case RDMA_CONTROL_RAM_BLOCKS_REQUEST:
 | |
|             DPRINTF("Initial setup info requested.\n");
 | |
| 
 | |
|             if (rdma->pin_all) {
 | |
|                 ret = qemu_rdma_reg_whole_ram_blocks(rdma);
 | |
|                 if (ret) {
 | |
|                     fprintf(stderr, "rdma migration: error dest "
 | |
|                                     "registering ram blocks!\n");
 | |
|                     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 =
 | |
|                     (uint64_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) {
 | |
|                 fprintf(stderr, "rdma migration: error sending remote info!\n");
 | |
|                 goto out;
 | |
|             }
 | |
| 
 | |
|             break;
 | |
|         case RDMA_CONTROL_REGISTER_REQUEST:
 | |
|             DDPRINTF("There are %d registration requests\n", 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];
 | |
| 
 | |
|                 DDPRINTF("Registration request (%d): index %d, current_addr %"
 | |
|                          PRIu64 " chunks: %" PRIu64 "\n", 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,
 | |
|                             (uint8_t *)host_addr, NULL, ®_result->rkey,
 | |
|                             chunk, chunk_start, chunk_end)) {
 | |
|                     fprintf(stderr, "cannot get rkey!\n");
 | |
|                     ret = -EINVAL;
 | |
|                     goto out;
 | |
|                 }
 | |
| 
 | |
|                 reg_result->host_addr = (uint64_t) block->local_host_addr;
 | |
| 
 | |
|                 DDPRINTF("Registered rkey for this request: %x\n",
 | |
|                                 reg_result->rkey);
 | |
| 
 | |
|                 result_to_network(reg_result);
 | |
|             }
 | |
| 
 | |
|             ret = qemu_rdma_post_send_control(rdma,
 | |
|                             (uint8_t *) results, ®_resp);
 | |
| 
 | |
|             if (ret < 0) {
 | |
|                 fprintf(stderr, "Failed to send control buffer!\n");
 | |
|                 goto out;
 | |
|             }
 | |
|             break;
 | |
|         case RDMA_CONTROL_UNREGISTER_REQUEST:
 | |
|             DDPRINTF("There are %d unregistration requests\n", 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);
 | |
| 
 | |
|                 DDPRINTF("Unregistration request (%d): "
 | |
|                          " index %d, chunk %" PRIu64 "\n",
 | |
|                          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--;
 | |
| 
 | |
|                 DDPRINTF("Unregistered chunk %" PRIu64 " successfully.\n",
 | |
|                             reg->key.chunk);
 | |
|             }
 | |
| 
 | |
|             ret = qemu_rdma_post_send_control(rdma, NULL, &unreg_resp);
 | |
| 
 | |
|             if (ret < 0) {
 | |
|                 fprintf(stderr, "Failed to send control buffer!\n");
 | |
|                 goto out;
 | |
|             }
 | |
|             break;
 | |
|         case RDMA_CONTROL_REGISTER_RESULT:
 | |
|             fprintf(stderr, "Invalid RESULT message at dest.\n");
 | |
|             ret = -EIO;
 | |
|             goto out;
 | |
|         default:
 | |
|             fprintf(stderr, "Unknown control message %s\n",
 | |
|                                 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();
 | |
| 
 | |
|     DDDPRINTF("start section: %" PRIu64 "\n", 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;
 | |
|         DPRINTF("Sending registration setup for ram blocks...\n");
 | |
| 
 | |
|         /*
 | |
|          * 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;
 | |
|             }
 | |
|         }
 | |
|     }
 | |
| 
 | |
|     DDDPRINTF("Sending registration finish %" PRIu64 "...\n", 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;
 | |
| }
 | |
| 
 | |
| 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,
 | |
| };
 | |
| 
 | |
| 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;
 | |
| 
 | |
|     DPRINTF("Accepting rdma connection...\n");
 | |
|     ret = qemu_rdma_accept(rdma);
 | |
| 
 | |
|     if (ret) {
 | |
|         ERROR(errp, "RDMA Migration initialization failed!");
 | |
|         return;
 | |
|     }
 | |
| 
 | |
|     DPRINTF("Accepted migration\n");
 | |
| 
 | |
|     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;
 | |
| 
 | |
|     DPRINTF("Starting RDMA-based incoming migration\n");
 | |
|     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;
 | |
|     }
 | |
| 
 | |
|     DPRINTF("qemu_rdma_dest_init success\n");
 | |
| 
 | |
|     ret = rdma_listen(rdma->listen_id, 5);
 | |
| 
 | |
|     if (ret) {
 | |
|         ERROR(errp, "listening on socket!");
 | |
|         goto err;
 | |
|     }
 | |
| 
 | |
|     DPRINTF("rdma_listen success\n");
 | |
| 
 | |
|     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_X_RDMA_PIN_ALL]);
 | |
| 
 | |
|     if (ret) {
 | |
|         goto err;
 | |
|     }
 | |
| 
 | |
|     DPRINTF("qemu_rdma_source_init success\n");
 | |
|     ret = qemu_rdma_connect(rdma, &local_err);
 | |
| 
 | |
|     if (ret) {
 | |
|         goto err;
 | |
|     }
 | |
| 
 | |
|     DPRINTF("qemu_rdma_source_connect success\n");
 | |
| 
 | |
|     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);
 | |
| }
 |