Documentation of the module role and API is in the patch at
replication/qemu-repagent.txt
The main motivation behind the module is to allow replication of VMs in a
virtualization environment like RhevM.
To achieve this we need basic replication support in Qemu.
This is the first submission of this module, which was written as a Proof
Of Concept, and used successfully for replicating and recovering a Qemu VM.
Points and open issues:
* The module interfaces the Qemu storage stack at block.c
generic layer. Is this the right place to intercept/inject IOs?
* The patch contains performing IO reads invoked by a new
thread (a TCP listener thread). See repaget_read_vol in repagent.c. It is
not protected by any lock – is this OK?
* VM ID – the replication system implies an environment with
several VMs connected to a central replication system (Rephub).
This requires some sort of identification for a VM. The
current patch does not include a VM ID – I did not find any adequate ID to
use.
Any suggestions?
Appreciate any feedback or suggestions. Thanks,
Ori.
From 5a0d88689ddcf325f25fdfca2a2012f1bbf141b9 Mon Sep 17 00:00:00 2001
From: Ori Mamluk<address@hidden(none)>
Date: Tue, 7 Feb 2012 11:12:12 +0200
Subject: [PATCH] Added replication agent module (repagent) to Qemu under
replication directory, added repagent configure and run
options, and the repagent API usage in bloc
Added build options to ./configure: --enable-replication --disable-replicat
Added a commandline option to enable: -repagent<rep hub IP>
Added the module files under replication.
Signed-off-by: Ori Mamluk<address@hidden>
---
Makefile | 9 +-
Makefile.objs | 6 +
block.c | 20 +++-
configure | 11 ++
qemu-options.hx | 6 +
replication/qemu-repagent.txt | 104 +++++++++++++
replication/repagent.c | 322
+++++++++++++++++++++++++++++++++++++++++
replication/repagent.h | 46 ++++++
replication/repagent_client.c | 138 ++++++++++++++++++
replication/repagent_client.h | 36 +++++
replication/repcmd.h | 59 ++++++++
replication/repcmd_listener.c | 137 +++++++++++++++++
replication/repcmd_listener.h | 32 ++++
replication/rephub_cmds.h | 150 +++++++++++++++++++
replication/rephub_defs.h | 40 +++++
vl.c | 10 ++
16 files changed, 1121 insertions(+), 5 deletions(-)
mode change 100644 => 100755 Makefile.objs
mode change 100644 => 100755 qemu-options.hx
create mode 100755 replication/qemu-repagent.txt
create mode 100644 replication/repagent.c
create mode 100644 replication/repagent.h
create mode 100644 replication/repagent_client.c
create mode 100644 replication/repagent_client.h
create mode 100644 replication/repcmd.h
create mode 100644 replication/repcmd_listener.c
create mode 100644 replication/repcmd_listener.h
create mode 100644 replication/rephub_cmds.h
create mode 100644 replication/rephub_defs.h
diff --git a/Makefile b/Makefile
index 4f6eaa4..a1b3701 100644
--- a/Makefile
+++ b/Makefile
@@ -149,9 +149,9 @@ qemu-img.o qemu-tool.o qemu-nbd.o qemu-io.o cmd.o
qemu-ga.o: $(GENERATED_HEADERS
tools-obj-y = qemu-tool.o $(oslib-obj-y) $(trace-obj-y) \
qemu-timer-common.o cutils.o
-qemu-img$(EXESUF): qemu-img.o $(tools-obj-y) $(block-obj-y)
-qemu-nbd$(EXESUF): qemu-nbd.o $(tools-obj-y) $(block-obj-y)
-qemu-io$(EXESUF): qemu-io.o cmd.o $(tools-obj-y) $(block-obj-y)
+qemu-img$(EXESUF): qemu-img.o $(tools-obj-y) $(block-obj-y)
$(replication-obj-y)
+qemu-nbd$(EXESUF): qemu-nbd.o $(tools-obj-y) $(block-obj-y)
$(replication-obj-y)
+qemu-io$(EXESUF): qemu-io.o cmd.o $(tools-obj-y) $(block-obj-y)
$(replication-obj-y)
qemu-img-cmds.h: $(SRC_PATH)/qemu-img-cmds.hx
$(call quiet-command,sh $(SRC_PATH)/scripts/hxtool -h< $< >
$@," GEN $@")
@@ -228,6 +228,7 @@ clean:
rm -f trace-dtrace.dtrace trace-dtrace.dtrace-timestamp
rm -f trace-dtrace.h trace-dtrace.h-timestamp
rm -rf $(qapi-dir)
+ rm -f replication/*.{o,d}
$(MAKE) -C tests clean
for d in $(ALL_SUBDIRS) $(QEMULIBS) libcacard; do \
if test -d $$d; then $(MAKE) -C $$d $@ || exit 1; fi; \
@@ -387,4 +388,4 @@ tar:
rm -rf /tmp/$(FILE)
# Include automatically generated dependency files
--include $(wildcard *.d audio/*.d slirp/*.d block/*.d net/*.d ui/*.d
qapi/*.d qga/*.d)
+-include $(wildcard *.d audio/*.d slirp/*.d block/*.d net/*.d ui/*.d
qapi/*.d qga/*.d replication/*.d)
diff --git a/Makefile.objs b/Makefile.objs
old mode 100644
new mode 100755
index d7a6539..dbd6f15
--- a/Makefile.objs
+++ b/Makefile.objs
@@ -74,6 +74,7 @@ fsdev-obj-$(CONFIG_VIRTFS) += $(addprefix fsdev/,
$(fsdev-nested-y))
# CPUs and machines.
common-obj-y = $(block-obj-y) blockdev.o
+common-obj-y += $(replication-obj-$(CONFIG_REPLICATION))
common-obj-y += $(net-obj-y)
common-obj-y += $(qobject-obj-y)
common-obj-$(CONFIG_LINUX) += $(fsdev-obj-$(CONFIG_LINUX))
@@ -413,6 +414,11 @@ common-obj-y += qmp-marshal.o qapi-visit.o
qapi-types.o $(qapi-obj-y)
common-obj-y += qmp.o hmp.o
######################################################################
+# replication
+replication-nested-y = repagent_client.o repagent.o repcmd_listener.o
+replication-obj-y = $(addprefix replication/, $(replication-nested-y))
+
+######################################################################
# guest agent
qga-nested-y = guest-agent-commands.o guest-agent-command-state.o
diff --git a/block.c b/block.c
index 9bb236c..f3b8387 100644
--- a/block.c
+++ b/block.c
@@ -31,6 +31,10 @@
#include "qemu-coroutine.h"
#include "qmp-commands.h"
+#ifdef CONFIG_REPLICATION
+#include "replication/repagent.h"
+#endif
+
#ifdef CONFIG_BSD
#include<sys/types.h>
#include<sys/stat.h>
@@ -640,6 +644,9 @@ int bdrv_open(BlockDriverState *bs, const char
*filename, int flags,
goto unlink_and_fail;
}
+#ifdef CONFIG_REPLICATION
+ repagent_register_drive(filename, bs);
+#endif
/* Open the image */
ret = bdrv_open_common(bs, filename, flags, drv);
if (ret< 0) {
@@ -1292,6 +1299,17 @@ static int coroutine_fn
bdrv_co_do_writev(BlockDriverState *bs,
ret = drv->bdrv_co_writev(bs, sector_num, nb_sectors, qiov);
+
+#ifdef CONFIG_REPLICATION
+ if (bs->device_name[0] != '\0') {
+ /* We split the IO only at the highest stack driver layer.
+ Currently we know that by checking device_name - only
+ highest level (closest to the guest) has that name.
+ */
+ repagent_handle_protected_write(bs, sector_num,
+ nb_sectors, qiov, ret);
+ }
+#endif
if (bs->dirty_bitmap) {
set_dirty_bitmap(bs, sector_num, nb_sectors, 1);
}
@@ -1783,7 +1801,7 @@ int bdrv_has_zero_init(BlockDriverState *bs)
* 'nb_sectors' is the max value 'pnum' should be set to.
*/
int bdrv_is_allocated(BlockDriverState *bs, int64_t sector_num, int
nb_sectors,
- int *pnum)
+ int *pnum)
{
int64_t n;
if (!bs->drv->bdrv_is_allocated) {
diff --git a/configure b/configure
index 9e5da44..93d600e 100755
--- a/configure
+++ b/configure
@@ -179,6 +179,7 @@ spice=""
rbd=""
smartcard=""
smartcard_nss=""
+replication=""
usb_redir=""
opengl=""
zlib="yes"
@@ -772,6 +773,10 @@ for opt do
;;
--enable-smartcard-nss) smartcard_nss="yes"
;;
+ --disable-replication) replication="no"
+ ;;
+ --enable-replication) replication="yes"
+ ;;
--disable-usb-redir) usb_redir="no"
;;
--enable-usb-redir) usb_redir="yes"
@@ -1067,6 +1072,7 @@ echo " --disable-usb-redir disable usb network
redirection support"
echo " --enable-usb-redir enable usb network redirection support"
echo " --disable-guest-agent disable building of the QEMU Guest Agent"
echo " --enable-guest-agent enable building of the QEMU Guest Agent"
+echo " --enable-replication enable replication support"
echo ""
echo "NOTE: The object files are built at the place where configure is
launched"
exit 1
@@ -2733,6 +2739,7 @@ echo "curl support $curl"
echo "check support $check_utests"
echo "mingw32 support $mingw32"
echo "Audio drivers $audio_drv_list"
+echo "Replication $replication"
echo "Extra audio cards $audio_card_list"
echo "Block whitelist $block_drv_whitelist"
echo "Mixer emulation $mixemu"
@@ -3080,6 +3087,10 @@ if test "$smartcard_nss" = "yes" ; then
echo "CONFIG_SMARTCARD_NSS=y">> $config_host_mak
fi
+if test "$replication" = "yes" ; then
+ echo "CONFIG_REPLICATION=y">> $config_host_mak
+fi
+
if test "$usb_redir" = "yes" ; then
echo "CONFIG_USB_REDIR=y">> $config_host_mak
fi
diff --git a/qemu-options.hx b/qemu-options.hx
old mode 100644
new mode 100755
index 681eaf1..c97e4f8
--- a/qemu-options.hx
+++ b/qemu-options.hx
@@ -2602,3 +2602,9 @@ HXCOMM This is the last statement. Insert new options
before this line!
STEXI
@end table
ETEXI
+
+DEF("repagent", HAS_ARG, QEMU_OPTION_repagent,
+ "-repagent [hub IP/name]\n"
+ " Enable replication support for disks\n"
+ " hub is the ip or name of the machine running the
replication hub.\n",
+ QEMU_ARCH_ALL)
diff --git a/replication/qemu-repagent.txt b/replication/qemu-repagent.txt
new file mode 100755
index 0000000..e3b0c1e
--- /dev/null
+++ b/replication/qemu-repagent.txt
@@ -0,0 +1,104 @@
+ repagent - replication agent - a Qemu module for enabling
continuous async replication of VM volumes
+
+Introduction
+ This document describes a feature in Qemu - a replication
agent (AKA Repagent).
+ The Repagent is a new module that exposes an API to an
external replication system (AKA Rephub).
+ This API allows a Rephub to communicate with a Qemu VM and
continuously replicate its volumes.
+ The imlementation of a Rephub is outside of the scope of this
document. There may be several various Rephub
+ implenetations using the same repagent in Qemu.
+
+Main feature of Repagent
+ Repagent does the following:
+ * Report volumes - report a list of all volumes in a VM to
the Rephub.
+ * Report writes to a volume - send all writes made to a
protected volume to the Rephub.
+ The reporting of an IO is asyncronuous - i.e.
the IO is not delayed by the Repagent to get any acknowledgement from the
Rephub.
+ It is only copied to the Rephub.
+ * Read a protected volume - allows the Rephub to read a
protected volume, to enable the protected hub to syncronize the content of
a protected volume.
+
+Description of the Repagent module
+
+Build and run options
+ New configure option: --enable-replication
+ New command line option:
+ -repagent [hub IP/name]
+
Enable replication support for disks
+
hub is the ip or name of the machine running the replication hub.
+
+Module APIs
+ The Repagent module interfaces two main components:
+ 1. The Rephub - An external API based on socket messages
+ 2. The generic block layer- block.c
+
+ Rephub message API
+ The external replication API is a message
based API.
+ We won't go into the structure of the
messages here - just the sematics.
+
+ Messages list
+ (The updated list and
comments are in Rephub_cmds.h)
+
+ Messages from the Repagent to
the Rephub:
+ * Protected write
+ The Repagent
sends each write to a protected volume to the hub with the IO status.
+ In case the
status is bad the write content is not sent
+ * Report VM volumes
+ The agent
reports all the volumes of the VM to the hub.
+ * Read Volume Response
+ A response to
a Read Volume Request
+ Sends the
data read from a protected volume to the hub
+ * Agent shutdown
+ Notifies the
hub that the agent is about to shutdown.
+ This allows a
graceful shutdown. Any disconnection of an agent without
+ sending this
command will result in a full sync of the VM volumes.
+
+ Messages from the Rephub to
the Repagent:
+ * Start protect
+ The hub
instructs the agent to start protecting a volume. When a volume is protected
+ all its
writes are sent to to the hub.
+ With this
command the hub also assigns a volume ID to the given volume name.
+ * Read volume request
+ The hub
issues a read IO to a protected volume.
+ This command
is used during sync - when the hub needs to read unsyncronized
+ sections of a
protected volume.
+ This command
is a request, the read data is returned by the read volume response message
(see above).
+ block.c API
+ The API to the generic block storage layer
contains 3 functionalities:
+ 1. Handle writes to protected volumes
+ In bdrv_co_do_writev, each
write is reported to the Repagent module.
+ 2. Handle each new volume that registers
+ In bdrv_open - each new
bottom-level block driver that registers is reported.
+ 2. Read from a volume
+ Repagent calls bdrv_aio_readv
to handle read requests coming from the hub.
+
+
+General description of a Rephub - a replication system the repagent
connects to
+ This section describes in high level a sample Rephub - a
replication system that uses the repagent API
+ to replicate disks.
+ It describes a simple Rephub that comntinuously maintains a
mirror of the volumes of a VM.
+
+ Say we have a VM we want to protect - call it PVM, say it has
2 volumes - V1, V2.
+ Our Rephub is called SingleRephub - a Rephub protecting a
single VM.
+
+ Preparations
+ 1. The user chooses a host to rub SingleRephub - a different
host than PVM, call it Host2
+ 2. The user creates two volumes on Host2 - same sizes of V1
and V2, call them V1R (V1 recovery) and V2R.
+ 3. The user runs SingleRephub process on Host2, and gives V1R
and V2R as command line arguments.
+ From now on SingleRephub waits for the
protected VM repagent to connect.
+ 4. The user runs the protected VM PVM - and uses the switch
-repagent<Host2 IP>.
+
+ Runtime
+ 1. The repagent module connects to SingleRephub on startup.
+ 2. repagent reports V1 and V2 to SingleRephub.
+ 3. SingleRephub starts to perform an initial synchronization
of the protected volumes-
+ it reads each protected volume (V1 and V2) -
using read volume requests - and copies the data into the
+ recovery volume V1R and V2R.
+ 4. SingleRephub enters 'protection' mode - each write to the
protected volume is sent by the repagent to the Rephub,
+ and the Rephub performs the write on the
matching recovery volume.
+
+ * Note that during stage 3 writes to the protected volumes
are not ignored - they're kept in a bitmap,
+ and will be read again when stage 3 ends, in
an interative convergin process.
+
+ This flow continuously maintains an updated recovery volume.
+ If the protected system is damaged, the user can create a new
VM on Host2 with the replicated volumes attached to it.
+ The new VM is a replica of the protected system.
+
+
diff --git a/replication/repagent.c b/replication/repagent.c
new file mode 100644
index 0000000..c66eae7
--- /dev/null
+++ b/replication/repagent.c
@@ -0,0 +1,322 @@
+#include<string.h>
+#include<stdlib.h>
+#include<stdio.h>
+#include<pthread.h>
+#include<stdint.h>
+
+#include "block.h"
+#include "rephub_defs.h"
+#include "block_int.h"
+#include "repagent_client.h"
+#include "repagent.h"
+#include "rephub_cmds.h"
+
+#define ZERO_MEM_OBJ(pObj) memset(pObj, 0, sizeof(*pObj))
+#define REPAGENT_MAX_NUM_VOLUMES (64)
+#define REPAGENT_VOLUME_ID_NONE (0)
+
+typedef struct RepagentVolume {
+ uint64_t vol_id;
+ const char *vol_path;
+ BlockDriverState *driver_ptr;
+} RepagentVolume;
+
+struct RepAgentState {
+ int is_init;
+ int num_volumes;
+ RepagentVolume * volumes[REPAGENT_MAX_NUM_VOLUMES];
+};
+
+typedef struct RepagentReadVolIo {
+ QEMUIOVector qiov;
+ RepCmdReadVolReq rep_cmd;
+ uint8_t *buf;
+ struct timeval start_time;
+} RepagentReadVolIo;
+
+static int repagent_get_volume_by_name(const char *name);
+static void repagent_report_volumes_to_hub(void);
+static void repagent_vol_read_done(void *opaque, int ret);
+static struct timeval tsub(struct timeval t1, struct timeval t2);
+
+RepAgentState g_rep_agent = { 0 };
+
+void repagent_init(const char *hubname, int port)
+{
+ /* It is the responsibility of the thread to free this struct */
+ rephub_params *pParams = (rephub_params
*)g_malloc(sizeof(rephub_params));
+ if (hubname == NULL) {
+ hubname = "127.0.0.1";
+ }
+ if (port == 0) {
+ port = 9010;
+ }
+
+ printf("repagent_init %s\n", hubname);
+
+ pParams->port = port;
+ pParams->name = g_strdup(hubname);
+
+ pthread_t thread_id = 0;
+
+ /* Create the repagent client listener thread */
+ pthread_create(&thread_id, 0, repagent_listen, (void *) pParams);
+ pthread_detach(thread_id);
+}
+
+void repagent_register_drive(const char *drive_path,
+ BlockDriverState *driver_ptr)
+{
+ int i;
+ for (i = 0; i< g_rep_agent.num_volumes ; i++) {
+ RepagentVolume *vol = g_rep_agent.volumes[i];
+ if (vol != NULL) {
+ assert(
+ strcmp(drive_path, vol->vol_path) != 0
+&& driver_ptr != vol->driver_ptr);
+ }
+ }
+
+ assert(g_rep_agent.num_volumes< REPAGENT_MAX_NUM_VOLUMES);
+
+ printf("zerto repagent: Registering drive. Num drives %d, path %s\n",
+ g_rep_agent.num_volumes, drive_path);
+ g_rep_agent.volumes[i] =
+ (RepagentVolume *)g_malloc(sizeof(RepagentVolume));
+ g_rep_agent.volumes[i]->driver_ptr = driver_ptr;
+ /* orim todo strcpy? */
+ g_rep_agent.volumes[i]->vol_path = drive_path;
+
+ /* Orim todo thread-safety? */
+ g_rep_agent.num_volumes++;
+
+ repagent_report_volumes_to_hub();
+}
+
+/* orim todo destruction? */
+
+static RepagentVolume *repagent_get_protected_volume_by_driver(
+ BlockDriverState *bs)
+{
+ /* orim todo optimize search */
+ int i = 0;
+ for (i = 0; i< g_rep_agent.num_volumes ; i++) {
+ RepagentVolume *p_vol = g_rep_agent.volumes[i];
+ if (p_vol != NULL&& p_vol->driver_ptr == (void *) bs) {
+ return p_vol;
+ }
+ }
+ return NULL;
+}
+
+void repagent_handle_protected_write(BlockDriverState *bs, int64_t
sector_num,
+ int nb_sectors, QEMUIOVector *qiov, int ret_status)
+{
+ printf("zerto Protected write offset %lld, size %d, IO return status
%d",
+ (long long int) sector_num, nb_sectors, ret_status);
+ if (bs->filename != NULL) {
+ printf(", filename %s", bs->filename);
+ }
+
+ printf("\n");
+
+ RepagentVolume *p_vol = repagent_get_protected_volume_by_driver(bs);
+ if (p_vol == NULL || p_vol->vol_id == REPAGENT_VOLUME_ID_NONE) {
+ /* Unprotected */
+ printf("Got a write to an unprotected volume.\n");
+ return;
+ }
+
+ /* Report IO to rephub */
+
+ int data_size = qiov->size;
+ if (ret_status< 0) {
+ /* On failed ios we don't send the data to the hub */
+ data_size = 0;
+ }
+ uint8_t *pdata = NULL;
+ RepCmdProtectedWrite *p_cmd = (RepCmdProtectedWrite *) repcmd_new(
+ REPHUB_CMD_PROTECTED_WRITE, data_size, (uint8_t **)&pdata);
+
+ if (ret_status>= 0) {
+ qemu_iovec_to_buffer(qiov, pdata);
+ }
+
+ p_cmd->volume_id = p_vol->vol_id;
+ p_cmd->offset_sectors = sector_num;
+ p_cmd->size_sectors = nb_sectors;
+ p_cmd->ret_status = ret_status;
+
+ if (repagent_client_send((RepCmd *) p_cmd) != 0) {
+ printf("Error sending command\n");
+ }
+}
+
+static void repagent_report_volumes_to_hub(void)
+{
+ /* Report IO to rephub */
+ int i;
+ RepCmdDataReportVmVolumes *p_cmd_data = NULL;
+ RepCmdReportVmVolumes *p_cmd = (RepCmdReportVmVolumes *) repcmd_new(
+ REPHUB_CMD_REPORT_VM_VOLUMES,
+ g_rep_agent.num_volumes * sizeof(RepVmVolumeInfo),
+ (uint8_t **)&p_cmd_data);
+ p_cmd->num_volumes = g_rep_agent.num_volumes;
+ printf("reporting %u volumes\n", g_rep_agent.num_volumes);
+ for (i = 0; i< g_rep_agent.num_volumes ; i++) {
+ assert(g_rep_agent.volumes[i] != NULL);
+ printf("reporting volume %s size %u\n",
+ g_rep_agent.volumes[i]->vol_path,
+ (uint32_t) sizeof(p_cmd_data->volumes[i].name));
+ strncpy((char *) p_cmd_data->volumes[i].name,
+ g_rep_agent.volumes[i]->vol_path,
+ sizeof(p_cmd_data->volumes[i].name));
+ p_cmd_data->volumes[i].volume_id = g_rep_agent.volumes[i]->vol_id;
+ }
+ if (repagent_client_send((RepCmd *) p_cmd) != 0) {
+ printf("Error sending command\n");
+ }
+}
+
+int repaget_start_protect(RepCmdStartProtect *pcmd,
+ RepCmdDataStartProtect *pcmd_data)
+{
+ printf("Start protect vol %s, ID %llu\n", pcmd_data->volume_name,
+ (unsigned long long) pcmd->volume_id);
+ int vol_index = repagent_get_volume_by_name(pcmd_data->volume_name);
+ if (vol_index< 0) {
+ printf("The volume doesn't exist\n");
+ return TRUE;
+ }
+ /* orim todo protect */
+ g_rep_agent.volumes[vol_index]->vol_id = pcmd->volume_id;
+
+ return TRUE;
+}
+
+static int repagent_get_volume_by_name(const char *name)
+{
+ int i = 0;
+ for (i = 0; i< g_rep_agent.num_volumes ; i++) {
+ if (g_rep_agent.volumes[i] != NULL
+&& strcmp(name, g_rep_agent.volumes[i]->vol_path) == 0) {
+ return i;
+ }
+ }
+ return -1;
+}
+
+static int repagent_get_volume_by_id(uint64_t vol_id)
+{
+ int i = 0;
+ for (i = 0; i< g_rep_agent.num_volumes ; i++) {
+ if (g_rep_agent.volumes[i] != NULL
+&& g_rep_agent.volumes[i]->vol_id == vol_id) {
+ return i;
+ }
+ }
+ return -1;
+}
+
+int repaget_read_vol(RepCmdReadVolReq *pcmd, uint8_t *pdata)
+{
+ int index = repagent_get_volume_by_id(pcmd->volume_id);
+ int size_bytes = pcmd->size_sectors * 512;
+ if (index< 0) {
+ printf("Vol read - Could not find vol id %llu\n",
+ (unsigned long long int) pcmd->volume_id);
+ RepCmdReadVolRes *p_res_cmd = (RepCmdReadVolRes *) repcmd_new(
+ REPHUB_CMD_READ_VOL_RES, 0, NULL);
+ p_res_cmd->req_id = pcmd->req_id;
+ p_res_cmd->volume_id = pcmd->volume_id;
+ p_res_cmd->is_status_success = FALSE;
+ repagent_client_send((RepCmd *) p_res_cmd);
+ return TRUE;
+ }
+
+ printf("Vol read - driver %p, volId %llu, offset %llu, size %u\n",
+ g_rep_agent.volumes[index]->driver_ptr,
+ (unsigned long long int) pcmd->volume_id,
+ (unsigned long long int) pcmd->offset_sectors,
pcmd->size_sectors);
+
+ {
+ RepagentReadVolIo *read_xact = calloc(1,
sizeof(RepagentReadVolIo));
+
+/* BlockDriverAIOCB *acb; */
+
+ ZERO_MEM_OBJ(read_xact);
+
+ qemu_iovec_init(&read_xact->qiov, 1);
+
+ /*read_xact->buf =
+ qemu_blockalign(g_rep_agent.volumes[index]->driver_ptr,
size_bytes); */
+ read_xact->buf = (uint8_t *) g_malloc(size_bytes);
+ read_xact->rep_cmd = *pcmd;
+ qemu_iovec_add(&read_xact->qiov, read_xact->buf, size_bytes);
+
+ gettimeofday(&read_xact->start_time, NULL);
+ /* orim TODO - use the returned acb to cancel the request on
shutdown */
+ /*acb = */bdrv_aio_readv(g_rep_agent.volumes[index]->driver_ptr,
+ read_xact->rep_cmd.offset_sectors,&read_xact->qiov,
+ read_xact->rep_cmd.size_sectors, repagent_vol_read_done,
+ read_xact);
+ }
+
+ return TRUE;
+}
+
+static void repagent_vol_read_done(void *opaque, int ret)
+{
+ struct timeval t2;
+ RepagentReadVolIo *read_xact = (RepagentReadVolIo *) opaque;
+ uint8_t *pdata = NULL;
+ RepCmdReadVolRes *pcmd = (RepCmdReadVolRes *) repcmd_new(
+ REPHUB_CMD_READ_VOL_RES, read_xact->rep_cmd.size_sectors * 512,
+&pdata);
+ pcmd->req_id = read_xact->rep_cmd.req_id;
+ pcmd->volume_id = read_xact->rep_cmd.volume_id;
+ pcmd->is_status_success = FALSE;
+
+ printf("Protected vol read - volId %llu, offset %llu, size %u\n",
+ (unsigned long long int) read_xact->rep_cmd.volume_id,
+ (unsigned long long int) read_xact->rep_cmd.offset_sectors,
+ read_xact->rep_cmd.size_sectors);
+ gettimeofday(&t2, NULL);
+
+ if (ret>= 0) {
+ /* Read response - send the data to the hub */
+ t2 = tsub(t2, read_xact->start_time);
+ printf("Read prot vol done. Took %u seconds, %u us.",
+ (uint32_t) t2.tv_sec, (uint32_t) t2.tv_usec);
+
+ pcmd->is_status_success = TRUE;
+ /* orim todo optimize - don't copy, use the qiov buffer */
+ qemu_iovec_to_buffer(&read_xact->qiov, pdata);
+ } else {
+ printf("readv failed: %s\n", strerror(-ret));
+ }
+
+ repagent_client_send((RepCmd *) pcmd);
+
+ /*qemu_vfree(read_xact->buf); */
+ g_free(read_xact->buf);
+
+ g_free(read_xact);
+}
+
+static struct timeval tsub(struct timeval t1, struct timeval t2)
+{
+ t1.tv_usec -= t2.tv_usec;
+ if (t1.tv_usec< 0) {
+ t1.tv_usec += 1000000;
+ t1.tv_sec--;
+ }
+ t1.tv_sec -= t2.tv_sec;
+ return t1;
+}
+
+void repagent_client_connected(void)
+{
+ /* orim todo thread protection */
+ repagent_report_volumes_to_hub();
+}
diff --git a/replication/repagent.h b/replication/repagent.h
new file mode 100644
index 0000000..98ccbf2
--- /dev/null
+++ b/replication/repagent.h
@@ -0,0 +1,46 @@
+/*
+ * QEMU System Emulator
+ *
+ * Copyright (c) 2003-2008 Fabrice Bellard
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
copy
+ * of this software and associated documentation files (the "Software"),
to deal
+ * in the Software without restriction, including without limitation the
rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or
sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included
in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
IN
+ * THE SOFTWARE.
+ */
+#ifndef REPAGENT_H
+#define REPAGENT_H
+#include<stdint.h>
+
+#include "qemu-common.h"
+
+typedef struct RepAgentState RepAgentState;
+typedef struct RepCmdStartProtect RepCmdStartProtect;
+typedef struct RepCmdDataStartProtect RepCmdDataStartProtect;
+struct RepCmdReadVolReq;
+
+void repagent_init(const char *hubname, int port);
+void repagent_handle_protected_write(BlockDriverState *bs,
+ int64_t sector_num, int nb_sectors, QEMUIOVector *qiov, int
ret_status);
+void repagent_register_drive(const char *drive_path,
+ BlockDriverState *driver_ptr);
+int repaget_start_protect(RepCmdStartProtect *pcmd,
+ RepCmdDataStartProtect *pcmd_data);
+int repaget_read_vol(struct RepCmdReadVolReq *pcmd, uint8_t *pdata);
+void repagent_client_connected(void);
+
+
+#endif /* REPAGENT_H */
diff --git a/replication/repagent_client.c b/replication/repagent_client.c
new file mode 100644
index 0000000..4dd9ea4
--- /dev/null
+++ b/replication/repagent_client.c
@@ -0,0 +1,138 @@
+#include "repcmd.h"
+#include "rephub_cmds.h"
+#include "repcmd_listener.h"
+#include "repagent_client.h"
+#include "repagent.h"
+
+#include<string.h>
+#include<stdlib.h>
+#include<errno.h>
+#include<stdio.h>
+#include<resolv.h>
+#include<sys/socket.h>
+#include<arpa/inet.h>
+#include<netinet/in.h>
+#include<unistd.h>
+
+#define ZERO_MEM_OBJ(pObj) memset(pObj, 0, sizeof(*pObj))
+
+static void repagent_process_cmd(RepCmd *pCmd, uint8_t *pData, void
*clientPtr);
+
+typedef struct repagent_client_state {
+ int is_connected;
+ int is_terminate_receive;
+ int hsock;
+} repagent_client_state;
+
+static repagent_client_state g_client_state = { 0 };
+
+void *repagent_listen(void *pParam)
+{
+ rephub_params *pServerParams = (rephub_params *) pParam;
+ int host_port = pServerParams->port;
+ const char *host_name = pServerParams->name;
+
+ printf("Creating repagent listener thread...\n");
+ g_free(pServerParams);
+
+ struct sockaddr_in my_addr;
+
+ int err;
+ int retries = 0;
+
+ g_client_state.hsock = socket(AF_INET, SOCK_STREAM, 0);
+ if (g_client_state.hsock == -1) {
+ printf("Error initializing socket %d\n", errno);
+ return (void *) -1;
+ }
+
+ int param = 1;
+
+ if ((setsockopt(g_client_state.hsock, SOL_SOCKET, SO_REUSEADDR,
+ (char *)¶m, sizeof(int)) == -1)
+ || (setsockopt(g_client_state.hsock, SOL_SOCKET, SO_KEEPALIVE,
+ (char *)¶m, sizeof(int)) == -1)) {
+ printf("Error setting options %d\n", errno);
+ return (void *) -1;
+ }
+
+ my_addr.sin_family = AF_INET;
+ my_addr.sin_port = htons(host_port);
+ memset(&(my_addr.sin_zero), 0, 8);
+
+ my_addr.sin_addr.s_addr = inet_addr(host_name);
+
+ /* Reconnect loop */
+ while (!g_client_state.is_terminate_receive) {
+
+ if (connect(g_client_state.hsock, (struct sockaddr *)&my_addr,
+ sizeof(my_addr)) == -1) {
+ err = errno;
+ if (err != EINPROGRESS) {
+ retries++;
+ fprintf(
+ stderr,
+ "Error connecting socket %d. Host %s, port %u.
Retry count %d\n",
+ errno, host_name, host_port, retries);
+ usleep(5 * 1000 * 1000);
+ continue;
+ }
+ }
+ retries = 0;
+
+ g_client_state.is_connected = 1;
+
+ repagent_client_connected();
+ repcmd_listener(g_client_state.hsock, repagent_process_cmd, NULL);
+ close(g_client_state.hsock);
+
+ g_client_state.is_connected = 0;
+ }
+ return 0;
+}
+
+void repagent_process_cmd(RepCmd *pcmd, uint8_t *pdata, void *clientPtr)
+{
+ int is_free_data = 1;
+ printf("Repagent got cmd %d\n", pcmd->hdr.cmdid);
+ switch (pcmd->hdr.cmdid) {
+ case REPHUB_CMD_START_PROTECT: {
+ is_free_data = repaget_start_protect((RepCmdStartProtect *) pcmd,
+ (RepCmdDataStartProtect *) pdata);
+ }
+ break;
+ case REPHUB_CMD_READ_VOL_REQ: {
+ is_free_data = repaget_read_vol((RepCmdReadVolReq *) pcmd, pdata);
+ }
+ break;
+ default:
+ assert(0);
+ break;
+
+ }
+
+ if (is_free_data) {
+ g_free(pdata);
+ }
+}
+
+int repagent_client_send(RepCmd *p_cmd)
+{
+ int bytecount = 0;
+ printf("Send cmd %u, data size %u\n", p_cmd->hdr.cmdid,
+ p_cmd->hdr.data_size_bytes);
+ if (!g_client_state.is_connected) {
+ printf("Not connected to hub\n");
+ return -1;
+ }
+
+ bytecount = send(g_client_state.hsock, p_cmd,
+ sizeof(RepCmd) + p_cmd->hdr.data_size_bytes, 0);
+ if (bytecount< sizeof(RepCmd) + p_cmd->hdr.data_size_bytes) {
+ printf("Bad send %d, errno %d\n", bytecount, errno);
+ return bytecount;
+ }
+
+ /* Success */
+ return 0;
+}
diff --git a/replication/repagent_client.h b/replication/repagent_client.h
new file mode 100644
index 0000000..62a5377
--- /dev/null
+++ b/replication/repagent_client.h
@@ -0,0 +1,36 @@
+/*
+ * QEMU System Emulator
+ *
+ * Copyright (c) 2003-2008 Fabrice Bellard
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
copy
+ * of this software and associated documentation files (the "Software"),
to deal
+ * in the Software without restriction, including without limitation the
rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or
sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included
in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
IN
+ * THE SOFTWARE.
+ */
+#ifndef REPAGENT_CLIENT_H
+#define REPAGENT_CLIENT_H
+#include "repcmd.h"
+
+typedef struct rephub_params {
+ char *name;
+ int port;
+} rephub_params;
+
+void *repagent_listen(void *pParam);
+int repagent_client_send(RepCmd *p_cmd);
+
+#endif /* REPAGENT_CLIENT_H */
diff --git a/replication/repcmd.h b/replication/repcmd.h
new file mode 100644
index 0000000..8c6cf1b
--- /dev/null
+++ b/replication/repcmd.h
@@ -0,0 +1,59 @@
+/*
+ * QEMU System Emulator
+ *
+ * Copyright (c) 2003-2008 Fabrice Bellard
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
copy
+ * of this software and associated documentation files (the "Software"),
to deal
+ * in the Software without restriction, including without limitation the
rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or
sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included
in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
IN
+ * THE SOFTWARE.
+ */
+#ifndef REPCMD_H
+#define REPCMD_H
+
+#include<stdint.h>
+
+#define REPCMD_MAGIC1 (0x1122)
+#define REPCMD_MAGIC2 (0x3344)
+#define REPCMD_NUM_U32_PARAMS (11)
+
+enum RepCmds {
+ REPCMD_FIRST_INVALID = 0,
+ REPCMD_FIRST_HUBCMD = 1,
+ REPHUB_CMD_PROTECTED_WRITE = 2,
+ REPHUB_CMD_REPORT_VM_VOLUMES = 3,
+ REPHUB_CMD_START_PROTECT = 4,
+ REPHUB_CMD_READ_VOL_REQ = 5,
+ REPHUB_CMD_READ_VOL_RES = 6,
+ REPHUB_CMD_AGENT_SHUTDOWN = 7,
+};
+
+typedef struct RepCmdHdr {
+ uint16_t magic1;
+ uint16_t cmdid;
+ uint32_t data_size_bytes;
+} RepCmdHdr;
+
+typedef struct RepCmd {
+ RepCmdHdr hdr;
+ unsigned int parameters[REPCMD_NUM_U32_PARAMS];
+ unsigned int magic2;
+ uint8_t data[0];
+} RepCmd;
+
+RepCmd *repcmd_new(int cmd_id, int data_size, uint8_t **p_out_pdata);
+
+#endif /* REPCMD_H */
diff --git a/replication/repcmd_listener.c b/replication/repcmd_listener.c
new file mode 100644
index 0000000..a211927
--- /dev/null
+++ b/replication/repcmd_listener.c
@@ -0,0 +1,137 @@
+#include<fcntl.h>
+#include<string.h>
+#include<stdlib.h>
+#include<errno.h>
+#include<stdio.h>
+#include<netinet/in.h>
+#include<resolv.h>
+#include<sys/socket.h>
+#include<arpa/inet.h>
+#include<unistd.h>
+#include<pthread.h>
+#include<assert.h>
+
+/* Use the CONFIG_REPLICATION flag to determine whether
+ * we're under qemu build or a hub When under
+ * qemu use g_malloc */
+#ifdef CONFIG_REPLICATION
+#include<glib.h>
+#define REPCMD_MALLOC g_malloc
+#else
+#define REPCMD_MALLOC malloc
+#endif
+
+#include "repcmd.h"
+#include "repcmd_listener.h"
+
+#define ZERO_MEM_OBJ(pObj) memset((void *)pObj, 0, sizeof(*pObj))
+
+typedef struct RepCmdListenerState {
+ int is_terminate_receive;
+} RepCmdListenerState;
+
+static RepCmdListenerState g_listenerState = { 0 };
+
+/* Returns 0 for initiated termination or socket error value on error */
+int repcmd_listener(int hsock, pfn_received_cmd_cb callback, void
*clientPtr)
+{
+ RepCmd curCmd;
+ uint8_t *pReadBuf = (uint8_t *)&curCmd;
+ int bytesToGet = sizeof(RepCmd);
+ int bytesGotten = 0;
+ int isGotHeader = 0;
+ uint8_t *pdata = NULL;
+
+ assert(callback != NULL);
+
+ /* receive loop */
+ while (!g_listenerState.is_terminate_receive) {
+ int bytecount;
+
+ bytecount = recv(hsock, pReadBuf + bytesGotten,
+ bytesToGet - bytesGotten, 0);
+ if (bytecount == -1) {
+ fprintf(stderr, "Error receiving data %d\n", errno);
+ return errno;
+ }
+
+ if (bytecount == 0) {
+ printf("Disconnected\n");
+ return 0;
+ }
+ bytesGotten += bytecount;
+/* printf("Recieved bytes %d, got %d/%d\n",
+ bytecount, bytesGotten, bytesToGet); */
+ /* print content */
+ if (0) {
+ int i;
+ for (i = 0; i< bytecount ; i += 4) {
+ /*printf("%d/%d", i, bytecount/4); */
+ printf("%#x ",
+ *(int *) (&pReadBuf[bytesGotten - bytecount + i]));
+
+ }
+ printf("\n");
+ }
+ assert(bytesGotten<= bytesToGet);
+ if (bytesGotten == bytesToGet) {
+ int isGotData = 0;
+ bytesGotten = 0;
+ if (!isGotHeader) {
+ /* We just got the header */
+ isGotHeader = 1;
+
+ assert(curCmd.hdr.magic1 == REPCMD_MAGIC1);
+ assert(curCmd.magic2 == REPCMD_MAGIC2);
+ if (curCmd.hdr.data_size_bytes> 0) {
+ pdata = (uint8_t *)REPCMD_MALLOC(
+ curCmd.hdr.data_size_bytes);
+/* printf("malloc %p\n", pdata); */
+ pReadBuf = pdata;
+ } else {
+ /* no data */
+ isGotData = 1;
+ pdata = NULL;
+ }
+ bytesToGet = curCmd.hdr.data_size_bytes;
+ } else {
+ isGotData = 1;
+ }
+
+ if (isGotData) {
+ /* Got command and data */
+ (*callback)(&curCmd, pdata, clientPtr);
+
+ /* It's the callee responsibility to free pData */
+ pdata = NULL;
+ ZERO_MEM_OBJ(&curCmd);
+ pReadBuf = (uint8_t *)&curCmd;
+ bytesGotten = 0;
+ bytesToGet = sizeof(RepCmd);
+ isGotHeader = 0;
+ }
+ }
+ }
+ return 0;
+}
+
+RepCmd *repcmd_new(int cmd_id, int data_size, uint8_t **p_out_pdata)
+{
+ RepCmd *p_cmd = (RepCmd *)REPCMD_MALLOC(sizeof(RepCmd) + data_size);
+ assert(p_cmd != NULL);
+
+ /* Zero the CMD (not the data) */
+ ZERO_MEM_OBJ(p_cmd);
+
+ p_cmd->hdr.cmdid = cmd_id;
+ p_cmd->hdr.magic1 = REPCMD_MAGIC1;
+ p_cmd->magic2 = REPCMD_MAGIC2;
+ p_cmd->hdr.data_size_bytes = data_size;
+
+ if (p_out_pdata != NULL) {
+ *p_out_pdata = p_cmd->data;
+ }
+
+ return p_cmd;
+}
+
diff --git a/replication/repcmd_listener.h b/replication/repcmd_listener.h
new file mode 100644
index 0000000..c09a12e
--- /dev/null
+++ b/replication/repcmd_listener.h
@@ -0,0 +1,32 @@
+/*
+ * QEMU System Emulator
+ *
+ * Copyright (c) 2003-2008 Fabrice Bellard
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
copy
+ * of this software and associated documentation files (the "Software"),
to deal
+ * in the Software without restriction, including without limitation the
rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or
sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included
in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
IN
+ * THE SOFTWARE.
+ */
+#ifndef REPCMD_LISTENER_H
+#define REPCMD_LISTENER_H
+#include<stdint.h>
+typedef void (*pfn_received_cmd_cb)(RepCmd *pCmd,
+ uint8_t *pData, void *clientPtr);
+
+int repcmd_listener(int hsock, pfn_received_cmd_cb callback, void
*clientPtr);
+
+#endif /* REPCMD_LISTENER_H */
diff --git a/replication/rephub_cmds.h b/replication/rephub_cmds.h
new file mode 100644
index 0000000..820c37d
--- /dev/null
+++ b/replication/rephub_cmds.h
@@ -0,0 +1,150 @@
+/*
+ * QEMU System Emulator
+ *
+ * Copyright (c) 2003-2008 Fabrice Bellard
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
copy
+ * of this software and associated documentation files (the "Software"),
to deal
+ * in the Software without restriction, including without limitation the
rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or
sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included
in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
IN
+ * THE SOFTWARE.
+ */
+#ifndef REPHUB_CMDS_H
+#define REPHUB_CMDS_H
+
+#include<stdint.h>
+#include "repcmd.h"
+#include "rephub_defs.h"
+
+/*********************************************************
+ * RepCmd Report a protected IO
+ *
+ * REPHUB_CMD_PROTECTED_WRITE
+ * Direction: agent->hub
+ *
+ * Any write of a protected volume is send with this
+ * message to the hub, with its status.
+ * When case the status is bad no data is sent
+ *********************************************************/
+typedef struct RepCmdProtectedWrite {
+ RepCmdHdr hdr;
+ uint64_t volume_id;
+ uint64_t offset_sectors;
+ /* The size field duplicates the RepCmd size,
+ * but it is needed for reporting failed IOs' sizes */
+ uint32_t size_sectors;
+ int ret_status;
+} RepCmdProtectedWrite;
+
+/*********************************************************
+ * RepCmd Report VM volumes
+ *
+ * REPHUB_CMD_REPORT_VM_VOLUMES
+ * Direction: agent->hub
+ *
+ * The agent reports all the volumes of the VM
+ * to the hub.
+ *********************************************************/
+typedef struct RepVmVolumeInfo {
+ char name[REPHUB_MAX_VOL_NAME_LEN];
+ uint64_t volume_id;
+ uint32_t size_mb;
+} RepVmVolumeInfo;
+
+typedef struct RepCmdReportVmVolumes {
+ RepCmdHdr hdr;
+ int num_volumes;
+} RepCmdReportVmVolumes;
+
+typedef struct RepCmdDataReportVmVolumes {
+ RepVmVolumeInfo volumes[0];
+} RepCmdDataReportVmVolumes;
+
+
+/*********************************************************
+ * RepCmd Start protect
+ *
+ * REPHUB_CMD_START_PROTECT
+ * Direction: hub->agent
+ *
+ * The hub instructs the agent to start protecting
+ * a volume. When a volume is protected all its writes
+ * are sent to to the hub.
+ * With this command the hub also assigns a volume ID to
+ * the given volume name.
+ *********************************************************/
+typedef struct RepCmdStartProtect {
+ RepCmdHdr hdr;
+ uint64_t volume_id;
+} RepCmdStartProtect;
+
+typedef struct RepCmdDataStartProtect {
+ char volume_name[REPHUB_MAX_VOL_NAME_LEN];
+} RepCmdDataStartProtect;
+
+
+/*********************************************************
+ * RepCmd Read Volume Request
+ *
+ * REPHUB_CMD_READ_VOL_REQ
+ * Direction: hub->agent
+ *
+ * The hub issues a read IO to a protected volume.
+ * This command is used during sync - when the hub needs
+ * to read unsyncronized sections of a protected volume.
+ * This command is a request, the read data is returned
+ * by the response command REPHUB_CMD_READ_VOL_RES
+ *********************************************************/
+typedef struct RepCmdReadVolReq {
+ RepCmdHdr hdr;
+ int req_id;
+ int size_sectors;
+ uint64_t volume_id;
+ uint64_t offset_sectors;
+} RepCmdReadVolReq;
+
+/*********************************************************
+ * RepCmd Read Volume Response
+ *
+ * REPHUB_CMD_READ_VOL_RES
+ * Direction: agent->hub
+ *
+ * A response to REPHUB_CMD_READ_VOL_REQ.
+ * Sends the data read from a protected volume
+ *********************************************************/
+typedef struct RepCmdReadVolRes {
+ RepCmdHdr hdr;
+ int req_id;
+ int is_status_success;
+ uint64_t volume_id;
+} RepCmdReadVolRes;
+
+/*********************************************************
+ * RepCmd Agent shutdown
+ *
+ * REPHUB_CMD_AGENT_SHUTDOWN
+ * Direction: agent->hub
+ *
+ * Notifies the hub that the agent is about to shutdown.
+ * This allows a graceful shutdown. Any disconnection
+ * of an agent without sending this command will result
+ * in a full sync of the VM volumes.
+ *********************************************************/
+typedef struct RepCmdAgentShutdown {
+ RepCmdHdr hdr;
+} RepCmdAgentShutdown;
+
+
+#endif /* REPHUB_CMDS_H */
diff --git a/replication/rephub_defs.h b/replication/rephub_defs.h
new file mode 100644
index 0000000..e34e0ce
--- /dev/null
+++ b/replication/rephub_defs.h
@@ -0,0 +1,40 @@
+/*
+ * QEMU System Emulator
+ *
+ * Copyright (c) 2003-2008 Fabrice Bellard
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
copy
+ * of this software and associated documentation files (the "Software"),
to deal
+ * in the Software without restriction, including without limitation the
rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or
sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included
in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
IN
+ * THE SOFTWARE.
+ */
+#ifndef REP_HUB_DEFS_H
+#define REP_HUB_DEFS_H
+
+#include<stdint.h>
+
+#define REPHUB_MAX_VOL_NAME_LEN (1024)
+#define REPHUB_MAX_NUM_VOLUMES (512)
+
+#ifndef TRUE
+ #define TRUE (1)
+#endif
+
+#ifndef FALSE
+ #define FALSE (0)
+#endif
+
+#endif /* REP_HUB_DEFS_H */
diff --git a/vl.c b/vl.c
index 624da0f..506b5dc 100644
--- a/vl.c
+++ b/vl.c
@@ -167,6 +167,7 @@ int main(int argc, char **argv)
#include "ui/qemu-spice.h"
+#include "replication/repagent.h"
//#define DEBUG_NET
//#define DEBUG_SLIRP
@@ -2307,6 +2308,15 @@ int main(int argc, char **argv, char **envp)
drive_add(IF_DEFAULT, popt->index - QEMU_OPTION_hda,
optarg,
HD_OPTS);
break;
+ case QEMU_OPTION_repagent:
+#ifdef CONFIG_REPLICATION
+ repagent_init(optarg, 0);
+#else
+ fprintf(stderr, "Replication support is disabled. "
+ "Don't use -repagent option.\n");
+ exit(1);
+#endif
+ break;
case QEMU_OPTION_drive:
if (drive_def(optarg) == NULL) {
exit(1);