From: Andrew Cooper <andrew.cooper3@citrix.com>
To: Xen-devel <xen-devel@lists.xen.org>
Cc: Andrew Cooper <andrew.cooper3@citrix.com>,
Ian Jackson <Ian.Jackson@eu.citrix.com>,
Ian Campbell <Ian.Campbell@citrix.com>,
Wei Liu <wei.liu2@citrix.com>
Subject: [PATCH v4 19/29] tools/libxl: Infrastructure to convert a legacy stream
Date: Tue, 14 Jul 2015 11:59:34 +0100 [thread overview]
Message-ID: <1436871584-6522-20-git-send-email-andrew.cooper3@citrix.com> (raw)
In-Reply-To: <1436871584-6522-1-git-send-email-andrew.cooper3@citrix.com>
Provide a thin wrapper around exec()ing the python conversion utility,
and a stub implementation for cases where conversion is not wanted
(i.e. not x86).
One complication is that the caller of this interface needs to assume
ownership of the output fd, to prevent it being closed while still in
use in a datacopier.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
CC: Ian Campbell <Ian.Campbell@citrix.com>
CC: Ian Jackson <Ian.Jackson@eu.citrix.com>
CC: Wei Liu <wei.liu2@citrix.com>
---
v4: Formatting tweaks, description of the width field.
v3: Trimmed down massively from v2, provide libxl_no_convert_callout.c
---
tools/libxl/Makefile | 6 ++
tools/libxl/libxl_convert_callout.c | 171 ++++++++++++++++++++++++++++++++
tools/libxl/libxl_internal.h | 30 ++++++
tools/libxl/libxl_no_convert_callout.c | 35 +++++++
4 files changed, 242 insertions(+)
create mode 100644 tools/libxl/libxl_convert_callout.c
create mode 100644 tools/libxl/libxl_no_convert_callout.c
diff --git a/tools/libxl/Makefile b/tools/libxl/Makefile
index c71c5fe..68fe1c1 100644
--- a/tools/libxl/Makefile
+++ b/tools/libxl/Makefile
@@ -56,6 +56,12 @@ else
LIBXL_OBJS-y += libxl_nonetbuffer.o
endif
+ifeq ($(CONFIG_X86),y)
+LIBXL_OBJS-y += libxl_convert_callout.o
+else
+LIBXL_OBJS-y += libxl_no_convert_callout.o
+endif
+
LIBXL_OBJS-y += libxl_remus_device.o libxl_remus_disk_drbd.o
LIBXL_OBJS-$(CONFIG_X86) += libxl_cpuid.o libxl_x86.o libxl_psr.o
diff --git a/tools/libxl/libxl_convert_callout.c b/tools/libxl/libxl_convert_callout.c
new file mode 100644
index 0000000..65b4df9
--- /dev/null
+++ b/tools/libxl/libxl_convert_callout.c
@@ -0,0 +1,171 @@
+/*
+ * Copyright (C) 2014 Citrix Ltd.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published
+ * by the Free Software Foundation; version 2.1 only. with the special
+ * exception on linking described in file LICENSE.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Lesser General Public License for more details.
+ */
+
+#include "libxl_osdeps.h"
+
+#include "libxl_internal.h"
+
+/*
+ * Infrastructure for converting a legacy migration stream into a
+ * libxl v2 stream.
+ *
+ * This is done by fork()ing the python conversion script, which takes
+ * in a legacy stream, and puts out a suitably-formatted v2 stream.
+ */
+
+static void helper_exited(libxl__egc *egc, libxl__ev_child *ch,
+ pid_t pid, int status);
+static void helper_stop(libxl__egc *egc, libxl__ao_abortable *abrt, int rc);
+static void helper_done(libxl__egc *egc,
+ libxl__conversion_helper_state *chs);
+
+/*----- Entrypoints -----*/
+
+void libxl__conversion_helper_init(libxl__conversion_helper_state *chs)
+{
+ chs->v2_carefd = NULL;
+ chs->rc = 0;
+ libxl__ao_abortable_init(&chs->abrt);
+ libxl__ev_child_init(&chs->child);
+}
+
+int libxl__convert_legacy_stream(libxl__egc *egc,
+ libxl__conversion_helper_state *chs)
+{
+ STATE_AO_GC(chs->ao);
+ libxl__carefd *child_in = NULL, *child_out = NULL;
+ int rc = 0;
+
+ chs->abrt.ao = chs->ao;
+ chs->abrt.callback = helper_stop;
+ rc = libxl__ao_abortable_register(&chs->abrt);
+ if (rc) goto err;
+
+ libxl__carefd_begin();
+ int fds[2];
+ if (libxl_pipe(CTX, fds)) {
+ rc = ERROR_FAIL;
+ libxl__carefd_unlock();
+ goto err;
+ }
+ child_out = libxl__carefd_record(CTX, fds[0]);
+ child_in = libxl__carefd_record(CTX, fds[1]);
+ libxl__carefd_unlock();
+
+ pid_t pid = libxl__ev_child_fork(gc, &chs->child, helper_exited);
+ if (!pid) {
+ char * const args[] =
+ {
+ getenv("LIBXL_CONVERT_HELPER") ?:
+ LIBEXEC_BIN "/convert-legacy-stream",
+ "--in", GCSPRINTF("%d", chs->legacy_fd),
+ "--out", GCSPRINTF("%d", fds[1]),
+ /*
+ * The width calculation is an assumption for the common
+ * case. The conversion script needs to know the width of
+ * the toolstack which saved the legacy stream.
+ *
+ * In the overwhelming majority of cases, the width of the
+ * saving toolstack will be the same as our current
+ * width. To avoid extending the libxl API with a
+ * parameter intended to disappear shortly, this option
+ * has not been exposed to the caller.
+ *
+ * If more complicated conversion is required, the
+ * conversion script can be instantiated manually, which
+ * will bypass all of this conversion logic.
+ */
+ "--width", sizeof(unsigned long) == 8 ? "64" : "32",
+
+ "--guest", chs->hvm ? "hvm" : "pv",
+ "--format", "libxl",
+ /* "--verbose", */
+ NULL,
+ };
+
+ libxl_fd_set_cloexec(CTX, chs->legacy_fd, 0);
+ libxl_fd_set_cloexec(CTX, libxl__carefd_fd(child_in), 0);
+
+ libxl__exec(gc,
+ -1, -1, -1,
+ args[0], args, NULL);
+ }
+
+ libxl__carefd_close(child_in);
+ chs->v2_carefd = child_out;
+
+ assert(!rc);
+ return rc;
+
+ err:
+ libxl__ao_abortable_deregister(&chs->abrt);
+ assert(rc);
+ return rc;
+}
+
+void libxl__conversion_helper_abort(libxl__egc *egc,
+ libxl__conversion_helper_state *chs,
+ int rc)
+{
+ STATE_AO_GC(chs->ao);
+ assert(rc);
+
+ if (libxl__conversion_helper_inuse(chs)) {
+
+ if (!chs->rc)
+ chs->rc = rc;
+
+ libxl__kill(gc, chs->child.pid, SIGTERM, "conversion helper");
+ }
+}
+
+/*----- State handling -----*/
+
+static void helper_stop(libxl__egc *egc, libxl__ao_abortable *abrt, int rc)
+{
+ libxl__conversion_helper_state *chs = CONTAINER_OF(abrt, *chs, abrt);
+ STATE_AO_GC(chs->ao);
+
+ libxl__conversion_helper_abort(egc, chs, rc);
+}
+
+static void helper_exited(libxl__egc *egc, libxl__ev_child *ch,
+ pid_t pid, int status)
+{
+ libxl__conversion_helper_state *chs = CONTAINER_OF(ch, *chs, child);
+ STATE_AO_GC(chs->ao);
+
+ if (status) {
+ libxl_report_child_exitstatus(
+ CTX, chs->rc ? XTL_DEBUG : XTL_ERROR,
+ "conversion helper", pid, status);
+
+ if (!chs->rc)
+ chs->rc = ERROR_FAIL;
+ }
+
+ helper_done(egc, chs);
+}
+
+static void helper_done(libxl__egc *egc,
+ libxl__conversion_helper_state *chs)
+{
+ STATE_AO_GC(chs->ao);
+
+ assert(!libxl__conversion_helper_inuse(chs));
+
+ libxl__ao_abortable_deregister(&chs->abrt);
+
+ chs->completion_callback(egc, chs, chs->rc);
+}
diff --git a/tools/libxl/libxl_internal.h b/tools/libxl/libxl_internal.h
index 9397d53..97755fe 100644
--- a/tools/libxl/libxl_internal.h
+++ b/tools/libxl/libxl_internal.h
@@ -2917,6 +2917,36 @@ _hidden void libxl__remus_devices_commit(libxl__egc *egc,
libxl__remus_devices_state *rds);
_hidden int libxl__netbuffer_enabled(libxl__gc *gc);
+/*----- Legacy conversion helper -----*/
+typedef struct libxl__conversion_helper_state libxl__conversion_helper_state;
+
+struct libxl__conversion_helper_state {
+ /* public */
+ libxl__ao *ao;
+ int legacy_fd;
+ bool hvm; /* pv or hvm domain? */
+ libxl__carefd *v2_carefd; /* Filled by successful call to
+ * libxl__convert_legacy_stream(). Caller
+ * assumes ownership of the fd. */
+ void (*completion_callback)(
+ libxl__egc *egc, libxl__conversion_helper_state *chs, int rc);
+ /* private */
+ int rc;
+ libxl__ao_abortable abrt;
+ libxl__ev_child child;
+};
+
+_hidden void libxl__conversion_helper_init
+ (libxl__conversion_helper_state *chs);
+_hidden int libxl__convert_legacy_stream(libxl__egc *egc,
+ libxl__conversion_helper_state *chs);
+_hidden void libxl__conversion_helper_abort(libxl__egc *egc,
+ libxl__conversion_helper_state *chs, int rc);
+static inline bool libxl__conversion_helper_inuse
+ (const libxl__conversion_helper_state *chs)
+{ return libxl__ev_child_inuse(&chs->child); }
+
+
/*----- Domain suspend (save) state structure -----*/
typedef struct libxl__domain_suspend_state libxl__domain_suspend_state;
diff --git a/tools/libxl/libxl_no_convert_callout.c b/tools/libxl/libxl_no_convert_callout.c
new file mode 100644
index 0000000..6ba4d92
--- /dev/null
+++ b/tools/libxl/libxl_no_convert_callout.c
@@ -0,0 +1,35 @@
+/*
+ * Copyright (C) 2015 Citrix Ltd.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published
+ * by the Free Software Foundation; version 2.1 only. with the special
+ * exception on linking described in file LICENSE.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Lesser General Public License for more details.
+ */
+
+#include "libxl_osdeps.h"
+
+#include "libxl_internal.h"
+
+void libxl__conversion_helper_init(libxl__conversion_helper_state *chs)
+{
+ libxl__ev_child_init(&chs->child);
+}
+
+int libxl__convert_legacy_stream(libxl__egc *egc,
+ libxl__conversion_helper_state *chs)
+{
+ return ERROR_FAIL;
+}
+
+void libxl__conversion_helper_abort(libxl__egc *egc,
+ libxl__conversion_helper_state *chs,
+ int rc)
+{
+ /* no op */
+}
--
1.7.10.4
next prev parent reply other threads:[~2015-07-14 10:59 UTC|newest]
Thread overview: 39+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-07-14 10:59 [PATCH v4 00/27] Libxl migration v2 Andrew Cooper
2015-07-14 10:59 ` [PATCH v4 01/29] bsd-sys-queue-h-seddery: Massage `offsetof' Andrew Cooper
2015-07-14 10:59 ` [PATCH v4 02/29] tools/libxc: Always compile the compat qemu variables into xc_sr_context Andrew Cooper
2015-07-14 10:59 ` [PATCH v4 03/29] tools/libxl: Introduce ROUNDUP() Andrew Cooper
2015-07-14 10:59 ` [PATCH v4 04/29] tools/libxl: Introduce libxl__kill() Andrew Cooper
2015-07-14 10:59 ` [PATCH v4 05/29] tools/libxl: Stash all restore parameters in domain_create_state Andrew Cooper
2015-07-14 10:59 ` [PATCH v4 06/29] tools/libxl: Split libxl__domain_create_state.restore_fd in two Andrew Cooper
2015-07-14 10:59 ` [PATCH v4 07/29] tools/libxl: Extra management APIs for the save helper Andrew Cooper
2015-07-14 13:23 ` Ian Jackson
2015-07-14 10:59 ` [PATCH v4 08/29] tools/libxl: Add save_helper_state pointers to libxl__xc_domain_{save, restore}() Andrew Cooper
2015-07-14 10:59 ` [PATCH v4 09/29] tools/libxl: Fix libxl__carefd_opened() to be more useful with an invalid fd Andrew Cooper
2015-07-14 13:39 ` Ian Jackson
2015-07-14 14:08 ` Ian Campbell
2015-07-14 10:59 ` [PATCH v4 10/29] tools/xl: Mandatory flag indicating the format of the migration stream Andrew Cooper
2015-07-14 10:59 ` [PATCH v4 11/29] docs: Libxl migration v2 stream specification Andrew Cooper
2015-07-14 10:59 ` [PATCH v4 12/29] tools/python: Libxc migration v2 infrastructure Andrew Cooper
2015-07-14 10:59 ` [PATCH v4 13/29] tools/python: Libxl " Andrew Cooper
2015-07-14 10:59 ` [PATCH v4 14/29] tools/python: Other migration infrastructure Andrew Cooper
2015-07-14 10:59 ` [PATCH v4 15/29] tools/python: Verification utility for v2 stream spec compliance Andrew Cooper
2015-07-14 10:59 ` [PATCH v4 16/29] tools/python: Conversion utility for legacy migration streams Andrew Cooper
2015-07-14 10:59 ` [PATCH v4 17/29] tools/libxl: Migration v2 stream format Andrew Cooper
2015-07-14 10:59 ` [PATCH v4 18/29] tools/libxl: Infrastructure for reading a libxl migration v2 stream Andrew Cooper
2015-07-14 13:32 ` Ian Jackson
2015-07-14 10:59 ` Andrew Cooper [this message]
2015-07-14 13:33 ` [PATCH v4 19/29] tools/libxl: Infrastructure to convert a legacy stream Ian Jackson
2015-07-14 10:59 ` [PATCH v4 20/29] tools/libxl: Convert a legacy stream if needed Andrew Cooper
2015-07-14 13:37 ` Ian Jackson
2015-07-14 10:59 ` [PATCH v4 21/29] tools/libxc+libxl+xl: Restore v2 streams Andrew Cooper
2015-07-14 10:59 ` [PATCH v4 22/29] tools/libxl: Infrastructure for writing a v2 stream Andrew Cooper
2015-07-14 13:40 ` Ian Jackson
2015-07-14 10:59 ` [PATCH v4 23/29] tools/libxc+libxl+xl: Save v2 streams Andrew Cooper
2015-07-14 10:59 ` [PATCH v4 24/29] docs/libxl: Introduce CHECKPOINT_END to support migration v2 remus streams Andrew Cooper
2015-07-14 10:59 ` [PATCH v4 25/29] tools/libxl: Write checkpoint records into the stream Andrew Cooper
2015-07-14 10:59 ` [PATCH v4 26/29] tools/libx{c, l}: Introduce restore_callbacks.checkpoint() Andrew Cooper
2015-07-14 10:59 ` [PATCH v4 27/29] tools/libxl: Handle checkpoint records in a libxl migration v2 stream Andrew Cooper
2015-07-14 10:59 ` [PATCH v4 28/29] tools/libxc: Drop all XG_LIBXL_HVM_COMPAT code from libxc Andrew Cooper
2015-07-14 10:59 ` [PATCH v4 29/29] tools/libxl: Drop all knowledge of toolstack callbacks Andrew Cooper
2015-07-15 10:21 ` [PATCH v4 00/27] Libxl migration v2 Wei Liu
2015-07-15 10:25 ` Ian Jackson
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