* [Qemu-devel] [Minios-devel] [PATCH v6 0/<VARIOUS>] Begin to disentangle libxenctrl and provide some stable libraries
@ 2015-12-03 11:21 Ian Campbell
2015-12-03 11:23 ` [Qemu-devel] [PATCH QEMU-XEN v6 0/8] " Ian Campbell
2015-12-09 12:37 ` [Qemu-devel] [Minios-devel] [PATCH v6 0/<VARIOUS>] Begin to disentangle libxenctrl and provide some stable libraries Ian Campbell
0 siblings, 2 replies; 20+ messages in thread
From: Ian Campbell @ 2015-12-03 11:21 UTC (permalink / raw)
To: xen-devel
Cc: Wei Liu, Stefano Stabellini, Ian Jackson, qemu-devel,
minios-devel, samuel.thibault, Roger Pau Monne
In <1431963008.4944.80.camel@citrix.com> I proposed stabilising some
parts of the libxenctrl API/ABI by disaggregating into separate
libraries.
This is v6 of that set of series against:
xen
qemu-xen
qemu-xen-traditional
mini-os
NB: Samuel+minios-devel will only get the mini-os side and Stefano+qemu
-devel the qemu-xen side.
The code for all repos can be found in:
git://xenbits.xen.org/people/ianc/libxenctrl-split/xen.git v6
git://xenbits.xen.org/people/ianc/libxenctrl-split/qemu-xen.git v6
git://xenbits.xen.org/people/ianc/libxenctrl-split/qemu-xen-traditional.git v6
git://xenbits.xen.org/people/ianc/libxenctrl-split/mini-os.git v6
The tip of the xen.git branch contains an extra patch hacking Config.mk
to point to all the others above, which should get the correct things for
the HEAD of the branch, but not further back in time.
The new libraries here are:
* libxentoollog: Common logging infrastructure
* libxenevtchn: Userspace access to evtchns (via /dev/xen/evtchn etc)
* libxengnttab: Userspace access to grant tables (via /dev/xen/gnt??? etc)
* libxencall: Making hypercalls (i.e. the IOCTL_PRIVCMD_HYPERCALL type
functionality)
* libxenforeignmemory: Privileged mappings of foreign memory
(IOCTL_PRIVCMD_MMAP et al)
The first three were actually pretty distinct within libxenctrl already and
have not changed in quite some time.
Although the other two are somewhat new they are based on top of long
standing stable ioctls, which gives me some confidence.
Nonetheless I would appreciate extra review of at least the interface
headers of all of these with a particular eye to the suitability of these
interfaces being maintained in an ABI (_B_, not _P_) stable way going
forward.
Still to come would be libraries for specific out of tree purposes
(device model, kexec), which would be adding new library at the same
level as libxc I think, rather than underneath, i.e. also using the
libraries split out here, but hopefully not libxenctrl itself.
The new libraries use linker version-scripts to hopefully make future
ABI changes be possible in a compatible way.
Since last time:
* Major changes to the libxenforeignmemory interface, which necessitated
some changes on the qemu-xen side too, invalidating various
(Ack|Review)ed-by.
* Reordered the arguments to make the use of VLA possible in the future
* Allow err==NULL, this in turn lead to the realisation that the error
handling for a bunch of the xc_map_foreign_* functions which
transition => xc_map_foreign_bulk => xenforeigmemory_map in this
series was all wrong in expecting a NULL return on error when errors
can also be signalled in err[]. This lead to most of the dropped acks
and various reorderings/restructuring of changes
* Lots of docs updates based on feedback given, especially to the gnttab
interface.
Even with the dropped acks mini-os and qemu-xen-trad are fully acked, while
qemu-xen and xen are mostly acked (but had a few dropped acks since last
time).
The whole thing has been build tested on Linux (incl stubdoms), and on
FreeBSD. I have runtime on Linux with qemu-xen, qemu-xen-trad and stubdoms.
Neither NetBSD nor Solaris have been tested at all. It's certainly not
impossible that I've not got the #includes in the new files quite right.
http://xenbits.xen.org/people/ianc/libxenctrl-split/v6.html is the document
I've been using to try and track what I'm doing. It may not be all that
useful. The history of it is in the v6-with-doc branch of the xen.git
linked to above.
Last time proposed that these precursors (and the corresponding qemu-xen-
traditional + mini-os patches) should go in now:
tools/Rules.mk: Properly handle libraries with recursive dependencies.
tools: Refactor "xentoollog" into its own library
But I subsequently found a couple of build issues, which are addressed by
two new patches at the head of the xen series.
Note also that I've picked up "x86/libxc: add an arch domain config
parameter to xc_domain_create" into my xen branch, in order that I can work
against qemu mainline, I expect that to go in shortly and be dropped here
(just waiting on a qemu-xen-upstream-unstable osstest pass).
Ian.
^ permalink raw reply [flat|nested] 20+ messages in thread
* [Qemu-devel] [PATCH QEMU-XEN v6 0/8] Begin to disentangle libxenctrl and provide some stable libraries
2015-12-03 11:21 [Qemu-devel] [Minios-devel] [PATCH v6 0/<VARIOUS>] Begin to disentangle libxenctrl and provide some stable libraries Ian Campbell
@ 2015-12-03 11:23 ` Ian Campbell
2015-12-03 11:23 ` [Qemu-devel] [PATCH QEMU-XEN v6 1/8] xen_console: correctly cleanup primary console on teardown Ian Campbell
` (7 more replies)
2015-12-09 12:37 ` [Qemu-devel] [Minios-devel] [PATCH v6 0/<VARIOUS>] Begin to disentangle libxenctrl and provide some stable libraries Ian Campbell
1 sibling, 8 replies; 20+ messages in thread
From: Ian Campbell @ 2015-12-03 11:23 UTC (permalink / raw)
To: ian.jackson, wei.liu2, xen-devel
Cc: Ian Campbell, qemu-devel, stefano.stabellini
We intend to stabilise some parts of the libxenctrl interface by
splitting out some functionality into separate stable libraries.
This is the qemu-xen part of the first phase of that change.
This mail is (or is intended to be) a reply to a "0/<VARIOUS>"
super-intro mail covering all of the related patch series and which
contains more details.
Ian Campbell (8):
xen_console: correctly cleanup primary console on teardown.
xen: Switch to libxenevtchn interface for compat shims.
xen: Switch to libxengnttab interface for compat shims.
xen: Switch uses of xc_map_foreign_range into xc_map_foreign_pages
xen: Switch uses of xc_map_foreign_{pages,bulk} to use
libxenforeignmemory API.
xen: Use stable library interfaces when they are available.
xen: domainbuild: reopen libxenctrl interface after forking for domain
watcher.
xen: make it possible to build without the Xen PV domain builder
configure | 57 ++++++++++++++++-
hw/block/xen_disk.c | 38 +++++------
hw/char/xen_console.c | 19 +++---
hw/display/xenfb.c | 18 +++---
hw/net/xen_nic.c | 18 +++---
hw/xen/xen_backend.c | 44 ++++++-------
hw/xenpv/Makefile.objs | 4 +-
hw/xenpv/xen_domainbuild.c | 9 ++-
hw/xenpv/xen_machine_pv.c | 15 +++--
include/hw/xen/xen_backend.h | 5 +-
include/hw/xen/xen_common.h | 147 +++++++++++++++++++++++++++++++++++--------
xen-common.c | 6 ++
xen-hvm.c | 39 ++++++------
xen-mapcache.c | 6 +-
14 files changed, 297 insertions(+), 128 deletions(-)
--
2.1.4
^ permalink raw reply [flat|nested] 20+ messages in thread
* [Qemu-devel] [PATCH QEMU-XEN v6 1/8] xen_console: correctly cleanup primary console on teardown.
2015-12-03 11:23 ` [Qemu-devel] [PATCH QEMU-XEN v6 0/8] " Ian Campbell
@ 2015-12-03 11:23 ` Ian Campbell
2015-12-03 11:23 ` [Qemu-devel] [PATCH QEMU-XEN v6 2/8] xen: Switch to libxenevtchn interface for compat shims Ian Campbell
` (6 subsequent siblings)
7 siblings, 0 replies; 20+ messages in thread
From: Ian Campbell @ 2015-12-03 11:23 UTC (permalink / raw)
To: ian.jackson, wei.liu2, xen-devel
Cc: Ian Campbell, qemu-devel, stefano.stabellini
All of the work in con_disconnect applies to the primary console case
(when xendev->dev is NULL). Therefore remove the early check and bail
and allow it to fall through. All of the existing code is correctly
conditional already.
The ->dev and ->gnttabdev handles are either both set or neither. For
consistency with con_initialise() with to the former here too.
With this con_initialise and con_disconnect now mirror each other.
Fix up a hard tab in the function while editing.
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Reviewed-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
---
v4: New patch based on feedback to "xen: Switch uses of
xc_map_foreign_bulk to use libxenforeignmemory API."
---
hw/char/xen_console.c | 7 ++-----
1 file changed, 2 insertions(+), 5 deletions(-)
diff --git a/hw/char/xen_console.c b/hw/char/xen_console.c
index eb7f450..63ade33 100644
--- a/hw/char/xen_console.c
+++ b/hw/char/xen_console.c
@@ -265,9 +265,6 @@ static void con_disconnect(struct XenDevice *xendev)
{
struct XenConsole *con = container_of(xendev, struct XenConsole, xendev);
- if (!xendev->dev) {
- return;
- }
if (con->chr) {
qemu_chr_add_handlers(con->chr, NULL, NULL, NULL, NULL);
qemu_chr_fe_release(con->chr);
@@ -275,12 +272,12 @@ static void con_disconnect(struct XenDevice *xendev)
xen_be_unbind_evtchn(&con->xendev);
if (con->sring) {
- if (!xendev->gnttabdev) {
+ if (!xendev->dev) {
munmap(con->sring, XC_PAGE_SIZE);
} else {
xc_gnttab_munmap(xendev->gnttabdev, con->sring, 1);
}
- con->sring = NULL;
+ con->sring = NULL;
}
}
--
2.1.4
^ permalink raw reply related [flat|nested] 20+ messages in thread
* [Qemu-devel] [PATCH QEMU-XEN v6 2/8] xen: Switch to libxenevtchn interface for compat shims.
2015-12-03 11:23 ` [Qemu-devel] [PATCH QEMU-XEN v6 0/8] " Ian Campbell
2015-12-03 11:23 ` [Qemu-devel] [PATCH QEMU-XEN v6 1/8] xen_console: correctly cleanup primary console on teardown Ian Campbell
@ 2015-12-03 11:23 ` Ian Campbell
2015-12-03 11:23 ` [Qemu-devel] [PATCH QEMU-XEN v6 3/8] xen: Switch to libxengnttab " Ian Campbell
` (5 subsequent siblings)
7 siblings, 0 replies; 20+ messages in thread
From: Ian Campbell @ 2015-12-03 11:23 UTC (permalink / raw)
To: ian.jackson, wei.liu2, xen-devel
Cc: Ian Campbell, qemu-devel, stefano.stabellini
In Xen 4.7 we are refactoring parts libxenctrl into a number of
separate libraries which will provide backward and forward API and ABI
compatiblity.
One such library will be libxenevtchn which provides access to event
channels.
In preparation for this switch the compatibility layer in xen_common.h
(which support building with older versions of Xen) to use what will
be the new library API. This means that the evtchn shim will disappear
for versions of Xen which include libxenevtchn.
To simplify things for the <= 4.0.0 support we wrap the int fd in a
malloc(sizeof int) such that the handle is always a pointer. This
leads to less typedef headaches and the need for
XC_HANDLER_INITIAL_VALUE etc for these interfaces.
Note that this patch does not add any support for actually using
libxenevtchn, it just adjusts the existing shims.
Note that xc_evtchn_alloc_unbound functionality remains in libxenctrl,
since that functionality is not exposed by /dev/xen/evtchn.
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Reviewed-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
---
v4: Ran checkpatch, fixed all errors
Allocate correct size for handle (i.e. not size of the ptr)
---
hw/xen/xen_backend.c | 31 ++++++++++++++++---------------
include/hw/xen/xen_backend.h | 2 +-
include/hw/xen/xen_common.h | 44 ++++++++++++++++++++++++++++++++++----------
xen-hvm.c | 25 +++++++++++++------------
4 files changed, 64 insertions(+), 38 deletions(-)
diff --git a/hw/xen/xen_backend.c b/hw/xen/xen_backend.c
index 2510e2e..ae2a1f0 100644
--- a/hw/xen/xen_backend.c
+++ b/hw/xen/xen_backend.c
@@ -243,19 +243,19 @@ static struct XenDevice *xen_be_get_xendev(const char *type, int dom, int dev,
xendev->debug = debug;
xendev->local_port = -1;
- xendev->evtchndev = xen_xc_evtchn_open(NULL, 0);
- if (xendev->evtchndev == XC_HANDLER_INITIAL_VALUE) {
+ xendev->evtchndev = xenevtchn_open(NULL, 0);
+ if (xendev->evtchndev == NULL) {
xen_be_printf(NULL, 0, "can't open evtchn device\n");
g_free(xendev);
return NULL;
}
- fcntl(xc_evtchn_fd(xendev->evtchndev), F_SETFD, FD_CLOEXEC);
+ fcntl(xenevtchn_fd(xendev->evtchndev), F_SETFD, FD_CLOEXEC);
if (ops->flags & DEVOPS_FLAG_NEED_GNTDEV) {
xendev->gnttabdev = xen_xc_gnttab_open(NULL, 0);
if (xendev->gnttabdev == XC_HANDLER_INITIAL_VALUE) {
xen_be_printf(NULL, 0, "can't open gnttab device\n");
- xc_evtchn_close(xendev->evtchndev);
+ xenevtchn_close(xendev->evtchndev);
g_free(xendev);
return NULL;
}
@@ -306,8 +306,8 @@ static struct XenDevice *xen_be_del_xendev(int dom, int dev)
g_free(xendev->fe);
}
- if (xendev->evtchndev != XC_HANDLER_INITIAL_VALUE) {
- xc_evtchn_close(xendev->evtchndev);
+ if (xendev->evtchndev != NULL) {
+ xenevtchn_close(xendev->evtchndev);
}
if (xendev->gnttabdev != XC_HANDLER_INITIAL_VALUE) {
xc_gnttab_close(xendev->gnttabdev);
@@ -691,13 +691,14 @@ static void xen_be_evtchn_event(void *opaque)
struct XenDevice *xendev = opaque;
evtchn_port_t port;
- port = xc_evtchn_pending(xendev->evtchndev);
+ port = xenevtchn_pending(xendev->evtchndev);
if (port != xendev->local_port) {
- xen_be_printf(xendev, 0, "xc_evtchn_pending returned %d (expected %d)\n",
+ xen_be_printf(xendev, 0,
+ "xenevtchn_pending returned %d (expected %d)\n",
port, xendev->local_port);
return;
}
- xc_evtchn_unmask(xendev->evtchndev, port);
+ xenevtchn_unmask(xendev->evtchndev, port);
if (xendev->ops->event) {
xendev->ops->event(xendev);
@@ -740,14 +741,14 @@ int xen_be_bind_evtchn(struct XenDevice *xendev)
if (xendev->local_port != -1) {
return 0;
}
- xendev->local_port = xc_evtchn_bind_interdomain
+ xendev->local_port = xenevtchn_bind_interdomain
(xendev->evtchndev, xendev->dom, xendev->remote_port);
if (xendev->local_port == -1) {
- xen_be_printf(xendev, 0, "xc_evtchn_bind_interdomain failed\n");
+ xen_be_printf(xendev, 0, "xenevtchn_bind_interdomain failed\n");
return -1;
}
xen_be_printf(xendev, 2, "bind evtchn port %d\n", xendev->local_port);
- qemu_set_fd_handler(xc_evtchn_fd(xendev->evtchndev),
+ qemu_set_fd_handler(xenevtchn_fd(xendev->evtchndev),
xen_be_evtchn_event, NULL, xendev);
return 0;
}
@@ -757,15 +758,15 @@ void xen_be_unbind_evtchn(struct XenDevice *xendev)
if (xendev->local_port == -1) {
return;
}
- qemu_set_fd_handler(xc_evtchn_fd(xendev->evtchndev), NULL, NULL, NULL);
- xc_evtchn_unbind(xendev->evtchndev, xendev->local_port);
+ qemu_set_fd_handler(xenevtchn_fd(xendev->evtchndev), NULL, NULL, NULL);
+ xenevtchn_unbind(xendev->evtchndev, xendev->local_port);
xen_be_printf(xendev, 2, "unbind evtchn port %d\n", xendev->local_port);
xendev->local_port = -1;
}
int xen_be_send_notify(struct XenDevice *xendev)
{
- return xc_evtchn_notify(xendev->evtchndev, xendev->local_port);
+ return xenevtchn_notify(xendev->evtchndev, xendev->local_port);
}
/*
diff --git a/include/hw/xen/xen_backend.h b/include/hw/xen/xen_backend.h
index 3b4125e..a90314f 100644
--- a/include/hw/xen/xen_backend.h
+++ b/include/hw/xen/xen_backend.h
@@ -46,7 +46,7 @@ struct XenDevice {
int remote_port;
int local_port;
- XenEvtchn evtchndev;
+ xenevtchn_handle *evtchndev;
XenGnttab gnttabdev;
struct XenDevOps *ops;
diff --git a/include/hw/xen/xen_common.h b/include/hw/xen/xen_common.h
index 4ac0c6f..5c51b44 100644
--- a/include/hw/xen/xen_common.h
+++ b/include/hw/xen/xen_common.h
@@ -39,17 +39,38 @@ static inline void *xc_map_foreign_bulk(int xc_handle, uint32_t dom, int prot,
#if CONFIG_XEN_CTRL_INTERFACE_VERSION < 410
typedef int XenXC;
-typedef int XenEvtchn;
+typedef int xenevtchn_handle;
typedef int XenGnttab;
# define XC_INTERFACE_FMT "%i"
# define XC_HANDLER_INITIAL_VALUE -1
-static inline XenEvtchn xen_xc_evtchn_open(void *logger,
- unsigned int open_flags)
+static inline xenevtchn_handle *xenevtchn_open(void *logger,
+ unsigned int open_flags)
{
- return xc_evtchn_open();
+ xenevtchn_handle *h = malloc(sizeof(*h));
+ if (!h) {
+ return NULL;
+ }
+ *h = xc_evtchn_open();
+ if (*h == -1) {
+ free(h);
+ h = NULL;
+ }
+ return h;
}
+static inline int xenevtchn_close(xenevtchn_handle *h)
+{
+ int rc = xc_evtchn_close(*h);
+ free(h);
+ return rc;
+}
+#define xenevtchn_fd(h) xc_evtchn_fd(*h)
+#define xenevtchn_pending(h) xc_evtchn_pending(*h)
+#define xenevtchn_notify(h, p) xc_evtchn_notify(*h, p)
+#define xenevtchn_bind_interdomain(h, d, p) xc_evtchn_bind_interdomain(*h, d, p)
+#define xenevtchn_unmask(h, p) xc_evtchn_unmask(*h, p)
+#define xenevtchn_unbind(h, p) xc_evtchn_unmask(*h, p)
static inline XenGnttab xen_xc_gnttab_open(void *logger,
unsigned int open_flags)
@@ -108,17 +129,20 @@ static inline void xs_close(struct xs_handle *xsh)
#else
typedef xc_interface *XenXC;
-typedef xc_evtchn *XenEvtchn;
+typedef xc_evtchn xenevtchn_handle;
typedef xc_gnttab *XenGnttab;
# define XC_INTERFACE_FMT "%p"
# define XC_HANDLER_INITIAL_VALUE NULL
-static inline XenEvtchn xen_xc_evtchn_open(void *logger,
- unsigned int open_flags)
-{
- return xc_evtchn_open(logger, open_flags);
-}
+#define xenevtchn_open(l, f) xc_evtchn_open(l, f);
+#define xenevtchn_close(h) xc_evtchn_close(h)
+#define xenevtchn_fd(h) xc_evtchn_fd(h)
+#define xenevtchn_pending(h) xc_evtchn_pending(h)
+#define xenevtchn_notify(h, p) xc_evtchn_notify(h, p)
+#define xenevtchn_bind_interdomain(h, d, p) xc_evtchn_bind_interdomain(h, d, p)
+#define xenevtchn_unmask(h, p) xc_evtchn_unmask(h, p)
+#define xenevtchn_unbind(h, p) xc_evtchn_unbind(h, p)
static inline XenGnttab xen_xc_gnttab_open(void *logger,
unsigned int open_flags)
diff --git a/xen-hvm.c b/xen-hvm.c
index 3d78a0c..6680782 100644
--- a/xen-hvm.c
+++ b/xen-hvm.c
@@ -109,7 +109,7 @@ typedef struct XenIOState {
/* evtchn local port for buffered io */
evtchn_port_t bufioreq_local_port;
/* the evtchn fd for polling */
- XenEvtchn xce_handle;
+ xenevtchn_handle *xce_handle;
/* which vcpu we are serving */
int send_vcpu;
@@ -714,7 +714,7 @@ static ioreq_t *cpu_get_ioreq(XenIOState *state)
int i;
evtchn_port_t port;
- port = xc_evtchn_pending(state->xce_handle);
+ port = xenevtchn_pending(state->xce_handle);
if (port == state->bufioreq_local_port) {
timer_mod(state->buffered_io_timer,
BUFFER_IO_MAX_DELAY + qemu_clock_get_ms(QEMU_CLOCK_REALTIME));
@@ -733,7 +733,7 @@ static ioreq_t *cpu_get_ioreq(XenIOState *state)
}
/* unmask the wanted port again */
- xc_evtchn_unmask(state->xce_handle, port);
+ xenevtchn_unmask(state->xce_handle, port);
/* get the io packet from shared memory */
state->send_vcpu = i;
@@ -1040,7 +1040,7 @@ static void handle_buffered_io(void *opaque)
BUFFER_IO_MAX_DELAY + qemu_clock_get_ms(QEMU_CLOCK_REALTIME));
} else {
timer_del(state->buffered_io_timer);
- xc_evtchn_unmask(state->xce_handle, state->bufioreq_local_port);
+ xenevtchn_unmask(state->xce_handle, state->bufioreq_local_port);
}
}
@@ -1084,7 +1084,8 @@ static void cpu_handle_ioreq(void *opaque)
}
req->state = STATE_IORESP_READY;
- xc_evtchn_notify(state->xce_handle, state->ioreq_local_port[state->send_vcpu]);
+ xenevtchn_notify(state->xce_handle,
+ state->ioreq_local_port[state->send_vcpu]);
}
}
@@ -1092,8 +1093,8 @@ static void xen_main_loop_prepare(XenIOState *state)
{
int evtchn_fd = -1;
- if (state->xce_handle != XC_HANDLER_INITIAL_VALUE) {
- evtchn_fd = xc_evtchn_fd(state->xce_handle);
+ if (state->xce_handle != NULL) {
+ evtchn_fd = xenevtchn_fd(state->xce_handle);
}
state->buffered_io_timer = timer_new_ms(QEMU_CLOCK_REALTIME, handle_buffered_io,
@@ -1131,7 +1132,7 @@ static void xen_exit_notifier(Notifier *n, void *data)
{
XenIOState *state = container_of(n, XenIOState, exit);
- xc_evtchn_close(state->xce_handle);
+ xenevtchn_close(state->xce_handle);
xs_daemon_close(state->xenstore);
}
@@ -1200,8 +1201,8 @@ int xen_hvm_init(PCMachineState *pcms,
state = g_malloc0(sizeof (XenIOState));
- state->xce_handle = xen_xc_evtchn_open(NULL, 0);
- if (state->xce_handle == XC_HANDLER_INITIAL_VALUE) {
+ state->xce_handle = xenevtchn_open(NULL, 0);
+ if (state->xce_handle == NULL) {
perror("xen: event channel open");
return -1;
}
@@ -1281,7 +1282,7 @@ int xen_hvm_init(PCMachineState *pcms,
/* FIXME: how about if we overflow the page here? */
for (i = 0; i < max_cpus; i++) {
- rc = xc_evtchn_bind_interdomain(state->xce_handle, xen_domid,
+ rc = xenevtchn_bind_interdomain(state->xce_handle, xen_domid,
xen_vcpu_eport(state->shared_page, i));
if (rc == -1) {
fprintf(stderr, "shared evtchn %d bind error %d\n", i, errno);
@@ -1290,7 +1291,7 @@ int xen_hvm_init(PCMachineState *pcms,
state->ioreq_local_port[i] = rc;
}
- rc = xc_evtchn_bind_interdomain(state->xce_handle, xen_domid,
+ rc = xenevtchn_bind_interdomain(state->xce_handle, xen_domid,
bufioreq_evtchn);
if (rc == -1) {
fprintf(stderr, "buffered evtchn bind error %d\n", errno);
--
2.1.4
^ permalink raw reply related [flat|nested] 20+ messages in thread
* [Qemu-devel] [PATCH QEMU-XEN v6 3/8] xen: Switch to libxengnttab interface for compat shims.
2015-12-03 11:23 ` [Qemu-devel] [PATCH QEMU-XEN v6 0/8] " Ian Campbell
2015-12-03 11:23 ` [Qemu-devel] [PATCH QEMU-XEN v6 1/8] xen_console: correctly cleanup primary console on teardown Ian Campbell
2015-12-03 11:23 ` [Qemu-devel] [PATCH QEMU-XEN v6 2/8] xen: Switch to libxenevtchn interface for compat shims Ian Campbell
@ 2015-12-03 11:23 ` Ian Campbell
2015-12-03 11:23 ` [Qemu-devel] [PATCH QEMU-XEN v6 4/8] xen: Switch uses of xc_map_foreign_range into xc_map_foreign_pages Ian Campbell
` (4 subsequent siblings)
7 siblings, 0 replies; 20+ messages in thread
From: Ian Campbell @ 2015-12-03 11:23 UTC (permalink / raw)
To: ian.jackson, wei.liu2, xen-devel
Cc: Ian Campbell, qemu-devel, stefano.stabellini
In Xen 4.7 we are refactoring parts libxenctrl into a number of
separate libraries which will provide backward and forward API and ABI
compatiblity.
One such library will be libxengnttab which provides access to grant
tables.
In preparation for this switch the compatibility layer in xen_common.h
(which support building with older versions of Xen) to use what will
be the new library API. This means that the gnttab shim will disappear
for versions of Xen which include libxengnttab.
To simplify things for the <= 4.0.0 support we wrap the int fd in a
malloc(sizeof int) such that the handle is always a pointer. This
leads to less typedef headaches and the need for
XC_HANDLER_INITIAL_VALUE etc for these interfaces.
Note that this patch does not add any support for actually using
libxengnttab, it just adjusts the existing shims.
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Reviewed-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
---
v4: Ran checkpatch, fixed all errors
Allocate correct size for handle (i.e. not size of the ptr)
Rebase onto "xen_console: correctly cleanup primary console on
teardown."
v5: Rebase over b4f72e31b924 "hw/net/xen_nic.c: Free 'netdev->txs'
when map 'netdev->rxs' fails" which added a new gnttab_munmap.
---
hw/block/xen_disk.c | 38 ++++++++++++++++++++------------------
hw/char/xen_console.c | 4 ++--
hw/net/xen_nic.c | 18 +++++++++---------
hw/xen/xen_backend.c | 10 +++++-----
include/hw/xen/xen_backend.h | 2 +-
include/hw/xen/xen_common.h | 42 ++++++++++++++++++++++++++++++++----------
6 files changed, 69 insertions(+), 45 deletions(-)
diff --git a/hw/block/xen_disk.c b/hw/block/xen_disk.c
index 8146650..12c01b6 100644
--- a/hw/block/xen_disk.c
+++ b/hw/block/xen_disk.c
@@ -171,11 +171,11 @@ static gint int_cmp(gconstpointer a, gconstpointer b, gpointer user_data)
static void destroy_grant(gpointer pgnt)
{
PersistentGrant *grant = pgnt;
- XenGnttab gnt = grant->blkdev->xendev.gnttabdev;
+ xengnttab_handle *gnt = grant->blkdev->xendev.gnttabdev;
- if (xc_gnttab_munmap(gnt, grant->page, 1) != 0) {
+ if (xengnttab_munmap(gnt, grant->page, 1) != 0) {
xen_be_printf(&grant->blkdev->xendev, 0,
- "xc_gnttab_munmap failed: %s\n",
+ "xengnttab_munmap failed: %s\n",
strerror(errno));
}
grant->blkdev->persistent_gnt_count--;
@@ -188,11 +188,11 @@ static void remove_persistent_region(gpointer data, gpointer dev)
{
PersistentRegion *region = data;
struct XenBlkDev *blkdev = dev;
- XenGnttab gnt = blkdev->xendev.gnttabdev;
+ xengnttab_handle *gnt = blkdev->xendev.gnttabdev;
- if (xc_gnttab_munmap(gnt, region->addr, region->num) != 0) {
+ if (xengnttab_munmap(gnt, region->addr, region->num) != 0) {
xen_be_printf(&blkdev->xendev, 0,
- "xc_gnttab_munmap region %p failed: %s\n",
+ "xengnttab_munmap region %p failed: %s\n",
region->addr, strerror(errno));
}
xen_be_printf(&blkdev->xendev, 3,
@@ -327,7 +327,7 @@ err:
static void ioreq_unmap(struct ioreq *ioreq)
{
- XenGnttab gnt = ioreq->blkdev->xendev.gnttabdev;
+ xengnttab_handle *gnt = ioreq->blkdev->xendev.gnttabdev;
int i;
if (ioreq->num_unmap == 0 || ioreq->mapped == 0) {
@@ -337,8 +337,9 @@ static void ioreq_unmap(struct ioreq *ioreq)
if (!ioreq->pages) {
return;
}
- if (xc_gnttab_munmap(gnt, ioreq->pages, ioreq->num_unmap) != 0) {
- xen_be_printf(&ioreq->blkdev->xendev, 0, "xc_gnttab_munmap failed: %s\n",
+ if (xengnttab_munmap(gnt, ioreq->pages, ioreq->num_unmap) != 0) {
+ xen_be_printf(&ioreq->blkdev->xendev, 0,
+ "xengnttab_munmap failed: %s\n",
strerror(errno));
}
ioreq->blkdev->cnt_map -= ioreq->num_unmap;
@@ -348,8 +349,9 @@ static void ioreq_unmap(struct ioreq *ioreq)
if (!ioreq->page[i]) {
continue;
}
- if (xc_gnttab_munmap(gnt, ioreq->page[i], 1) != 0) {
- xen_be_printf(&ioreq->blkdev->xendev, 0, "xc_gnttab_munmap failed: %s\n",
+ if (xengnttab_munmap(gnt, ioreq->page[i], 1) != 0) {
+ xen_be_printf(&ioreq->blkdev->xendev, 0,
+ "xengnttab_munmap failed: %s\n",
strerror(errno));
}
ioreq->blkdev->cnt_map--;
@@ -361,7 +363,7 @@ static void ioreq_unmap(struct ioreq *ioreq)
static int ioreq_map(struct ioreq *ioreq)
{
- XenGnttab gnt = ioreq->blkdev->xendev.gnttabdev;
+ xengnttab_handle *gnt = ioreq->blkdev->xendev.gnttabdev;
uint32_t domids[BLKIF_MAX_SEGMENTS_PER_REQUEST];
uint32_t refs[BLKIF_MAX_SEGMENTS_PER_REQUEST];
void *page[BLKIF_MAX_SEGMENTS_PER_REQUEST];
@@ -412,7 +414,7 @@ static int ioreq_map(struct ioreq *ioreq)
}
if (batch_maps && new_maps) {
- ioreq->pages = xc_gnttab_map_grant_refs
+ ioreq->pages = xengnttab_map_grant_refs
(gnt, new_maps, domids, refs, ioreq->prot);
if (ioreq->pages == NULL) {
xen_be_printf(&ioreq->blkdev->xendev, 0,
@@ -428,7 +430,7 @@ static int ioreq_map(struct ioreq *ioreq)
ioreq->blkdev->cnt_map += new_maps;
} else if (new_maps) {
for (i = 0; i < new_maps; i++) {
- ioreq->page[i] = xc_gnttab_map_grant_ref
+ ioreq->page[i] = xengnttab_map_grant_ref
(gnt, domids[i], refs[i], ioreq->prot);
if (ioreq->page[i] == NULL) {
xen_be_printf(&ioreq->blkdev->xendev, 0,
@@ -778,9 +780,9 @@ static void blk_alloc(struct XenDevice *xendev)
if (xen_mode != XEN_EMULATE) {
batch_maps = 1;
}
- if (xc_gnttab_set_max_grants(xendev->gnttabdev,
+ if (xengnttab_set_max_grants(xendev->gnttabdev,
MAX_GRANTS(max_requests, BLKIF_MAX_SEGMENTS_PER_REQUEST)) < 0) {
- xen_be_printf(xendev, 0, "xc_gnttab_set_max_grants failed: %s\n",
+ xen_be_printf(xendev, 0, "xengnttab_set_max_grants failed: %s\n",
strerror(errno));
}
}
@@ -987,7 +989,7 @@ static int blk_connect(struct XenDevice *xendev)
}
}
- blkdev->sring = xc_gnttab_map_grant_ref(blkdev->xendev.gnttabdev,
+ blkdev->sring = xengnttab_map_grant_ref(blkdev->xendev.gnttabdev,
blkdev->xendev.dom,
blkdev->ring_ref,
PROT_READ | PROT_WRITE);
@@ -1052,7 +1054,7 @@ static void blk_disconnect(struct XenDevice *xendev)
xen_be_unbind_evtchn(&blkdev->xendev);
if (blkdev->sring) {
- xc_gnttab_munmap(blkdev->xendev.gnttabdev, blkdev->sring, 1);
+ xengnttab_munmap(blkdev->xendev.gnttabdev, blkdev->sring, 1);
blkdev->cnt_map--;
blkdev->sring = NULL;
}
diff --git a/hw/char/xen_console.c b/hw/char/xen_console.c
index 63ade33..8c06c19 100644
--- a/hw/char/xen_console.c
+++ b/hw/char/xen_console.c
@@ -233,7 +233,7 @@ static int con_initialise(struct XenDevice *xendev)
PROT_READ|PROT_WRITE,
con->ring_ref);
} else {
- con->sring = xc_gnttab_map_grant_ref(xendev->gnttabdev, con->xendev.dom,
+ con->sring = xengnttab_map_grant_ref(xendev->gnttabdev, con->xendev.dom,
con->ring_ref,
PROT_READ|PROT_WRITE);
}
@@ -275,7 +275,7 @@ static void con_disconnect(struct XenDevice *xendev)
if (!xendev->dev) {
munmap(con->sring, XC_PAGE_SIZE);
} else {
- xc_gnttab_munmap(xendev->gnttabdev, con->sring, 1);
+ xengnttab_munmap(xendev->gnttabdev, con->sring, 1);
}
con->sring = NULL;
}
diff --git a/hw/net/xen_nic.c b/hw/net/xen_nic.c
index 0da16b4..6d69a6a 100644
--- a/hw/net/xen_nic.c
+++ b/hw/net/xen_nic.c
@@ -168,7 +168,7 @@ static void net_tx_packets(struct XenNetDev *netdev)
(txreq.flags & NETTXF_more_data) ? " more_data" : "",
(txreq.flags & NETTXF_extra_info) ? " extra_info" : "");
- page = xc_gnttab_map_grant_ref(netdev->xendev.gnttabdev,
+ page = xengnttab_map_grant_ref(netdev->xendev.gnttabdev,
netdev->xendev.dom,
txreq.gref, PROT_READ);
if (page == NULL) {
@@ -190,7 +190,7 @@ static void net_tx_packets(struct XenNetDev *netdev)
qemu_send_packet(qemu_get_queue(netdev->nic),
page + txreq.offset, txreq.size);
}
- xc_gnttab_munmap(netdev->xendev.gnttabdev, page, 1);
+ xengnttab_munmap(netdev->xendev.gnttabdev, page, 1);
net_tx_response(netdev, &txreq, NETIF_RSP_OKAY);
}
if (!netdev->tx_work) {
@@ -260,7 +260,7 @@ static ssize_t net_rx_packet(NetClientState *nc, const uint8_t *buf, size_t size
memcpy(&rxreq, RING_GET_REQUEST(&netdev->rx_ring, rc), sizeof(rxreq));
netdev->rx_ring.req_cons = ++rc;
- page = xc_gnttab_map_grant_ref(netdev->xendev.gnttabdev,
+ page = xengnttab_map_grant_ref(netdev->xendev.gnttabdev,
netdev->xendev.dom,
rxreq.gref, PROT_WRITE);
if (page == NULL) {
@@ -270,7 +270,7 @@ static ssize_t net_rx_packet(NetClientState *nc, const uint8_t *buf, size_t size
return -1;
}
memcpy(page + NET_IP_ALIGN, buf, size);
- xc_gnttab_munmap(netdev->xendev.gnttabdev, page, 1);
+ xengnttab_munmap(netdev->xendev.gnttabdev, page, 1);
net_rx_response(netdev, &rxreq, NETIF_RSP_OKAY, NET_IP_ALIGN, size, 0);
return size;
@@ -342,19 +342,19 @@ static int net_connect(struct XenDevice *xendev)
return -1;
}
- netdev->txs = xc_gnttab_map_grant_ref(netdev->xendev.gnttabdev,
+ netdev->txs = xengnttab_map_grant_ref(netdev->xendev.gnttabdev,
netdev->xendev.dom,
netdev->tx_ring_ref,
PROT_READ | PROT_WRITE);
if (!netdev->txs) {
return -1;
}
- netdev->rxs = xc_gnttab_map_grant_ref(netdev->xendev.gnttabdev,
+ netdev->rxs = xengnttab_map_grant_ref(netdev->xendev.gnttabdev,
netdev->xendev.dom,
netdev->rx_ring_ref,
PROT_READ | PROT_WRITE);
if (!netdev->rxs) {
- xc_gnttab_munmap(netdev->xendev.gnttabdev, netdev->txs, 1);
+ xengnttab_munmap(netdev->xendev.gnttabdev, netdev->txs, 1);
netdev->txs = NULL;
return -1;
}
@@ -379,11 +379,11 @@ static void net_disconnect(struct XenDevice *xendev)
xen_be_unbind_evtchn(&netdev->xendev);
if (netdev->txs) {
- xc_gnttab_munmap(netdev->xendev.gnttabdev, netdev->txs, 1);
+ xengnttab_munmap(netdev->xendev.gnttabdev, netdev->txs, 1);
netdev->txs = NULL;
}
if (netdev->rxs) {
- xc_gnttab_munmap(netdev->xendev.gnttabdev, netdev->rxs, 1);
+ xengnttab_munmap(netdev->xendev.gnttabdev, netdev->rxs, 1);
netdev->rxs = NULL;
}
}
diff --git a/hw/xen/xen_backend.c b/hw/xen/xen_backend.c
index ae2a1f0..966e34f 100644
--- a/hw/xen/xen_backend.c
+++ b/hw/xen/xen_backend.c
@@ -252,15 +252,15 @@ static struct XenDevice *xen_be_get_xendev(const char *type, int dom, int dev,
fcntl(xenevtchn_fd(xendev->evtchndev), F_SETFD, FD_CLOEXEC);
if (ops->flags & DEVOPS_FLAG_NEED_GNTDEV) {
- xendev->gnttabdev = xen_xc_gnttab_open(NULL, 0);
- if (xendev->gnttabdev == XC_HANDLER_INITIAL_VALUE) {
+ xendev->gnttabdev = xengnttab_open(NULL, 0);
+ if (xendev->gnttabdev == NULL) {
xen_be_printf(NULL, 0, "can't open gnttab device\n");
xenevtchn_close(xendev->evtchndev);
g_free(xendev);
return NULL;
}
} else {
- xendev->gnttabdev = XC_HANDLER_INITIAL_VALUE;
+ xendev->gnttabdev = NULL;
}
QTAILQ_INSERT_TAIL(&xendevs, xendev, next);
@@ -309,8 +309,8 @@ static struct XenDevice *xen_be_del_xendev(int dom, int dev)
if (xendev->evtchndev != NULL) {
xenevtchn_close(xendev->evtchndev);
}
- if (xendev->gnttabdev != XC_HANDLER_INITIAL_VALUE) {
- xc_gnttab_close(xendev->gnttabdev);
+ if (xendev->gnttabdev != NULL) {
+ xengnttab_close(xendev->gnttabdev);
}
QTAILQ_REMOVE(&xendevs, xendev, next);
diff --git a/include/hw/xen/xen_backend.h b/include/hw/xen/xen_backend.h
index a90314f..8e8857b 100644
--- a/include/hw/xen/xen_backend.h
+++ b/include/hw/xen/xen_backend.h
@@ -47,7 +47,7 @@ struct XenDevice {
int local_port;
xenevtchn_handle *evtchndev;
- XenGnttab gnttabdev;
+ xengnttab_handle *gnttabdev;
struct XenDevOps *ops;
QTAILQ_ENTRY(XenDevice) next;
diff --git a/include/hw/xen/xen_common.h b/include/hw/xen/xen_common.h
index 5c51b44..2cadd4f 100644
--- a/include/hw/xen/xen_common.h
+++ b/include/hw/xen/xen_common.h
@@ -40,7 +40,7 @@ static inline void *xc_map_foreign_bulk(int xc_handle, uint32_t dom, int prot,
typedef int XenXC;
typedef int xenevtchn_handle;
-typedef int XenGnttab;
+typedef int xengnttab_handle;
# define XC_INTERFACE_FMT "%i"
# define XC_HANDLER_INITIAL_VALUE -1
@@ -72,11 +72,31 @@ static inline int xenevtchn_close(xenevtchn_handle *h)
#define xenevtchn_unmask(h, p) xc_evtchn_unmask(*h, p)
#define xenevtchn_unbind(h, p) xc_evtchn_unmask(*h, p)
-static inline XenGnttab xen_xc_gnttab_open(void *logger,
- unsigned int open_flags)
+static inline xengnttab_handle *xengnttab_open(void *logger,
+ unsigned int open_flags)
{
- return xc_gnttab_open();
+ xengnttab_handle *h = malloc(sizeof(*h));
+ if (!h) {
+ return NULL;
+ }
+ *h = xc_gnttab_open();
+ if (*h == -1) {
+ free(h);
+ h = NULL;
+ }
+ return h;
}
+static inline int xengnttab_close(xengnttab_handle *h)
+{
+ int rc = xc_gnttab_close(*h);
+ free(h);
+ return rc;
+}
+#define xengnttab_set_max_grants(h, n) xc_gnttab_set_max_grants(*h, n)
+#define xengnttab_map_grant_ref(h, d, r, p) xc_gnttab_map_grant_ref(*h, d, r, p)
+#define xengnttab_map_grant_refs(h, c, d, r, p) \
+ xc_gnttab_map_grant_refs(*h, c, d, r, p)
+#define xengnttab_munmap(h, a, n) xc_gnttab_munmap(*h, a, n)
static inline XenXC xen_xc_interface_open(void *logger, void *dombuild_logger,
unsigned int open_flags)
@@ -130,7 +150,7 @@ static inline void xs_close(struct xs_handle *xsh)
typedef xc_interface *XenXC;
typedef xc_evtchn xenevtchn_handle;
-typedef xc_gnttab *XenGnttab;
+typedef xc_gnttab xengnttab_handle;
# define XC_INTERFACE_FMT "%p"
# define XC_HANDLER_INITIAL_VALUE NULL
@@ -144,11 +164,13 @@ typedef xc_gnttab *XenGnttab;
#define xenevtchn_unmask(h, p) xc_evtchn_unmask(h, p)
#define xenevtchn_unbind(h, p) xc_evtchn_unbind(h, p)
-static inline XenGnttab xen_xc_gnttab_open(void *logger,
- unsigned int open_flags)
-{
- return xc_gnttab_open(logger, open_flags);
-}
+#define xengnttab_open(l, f) xc_gnttab_open(l, f)
+#define xengnttab_close(h) xc_gnttab_close(h)
+#define xengnttab_set_max_grants(h, n) xc_gnttab_set_max_grants(h, n)
+#define xengnttab_map_grant_ref(h, d, r, p) xc_gnttab_map_grant_ref(h, d, r, p)
+#define xengnttab_munmap(h, a, n) xc_gnttab_munmap(h, a, n)
+#define xengnttab_map_grant_refs(h, c, d, r, p) \
+ xc_gnttab_map_grant_refs(h, c, d, r, p)
static inline XenXC xen_xc_interface_open(void *logger, void *dombuild_logger,
unsigned int open_flags)
--
2.1.4
^ permalink raw reply related [flat|nested] 20+ messages in thread
* [Qemu-devel] [PATCH QEMU-XEN v6 4/8] xen: Switch uses of xc_map_foreign_range into xc_map_foreign_pages
2015-12-03 11:23 ` [Qemu-devel] [PATCH QEMU-XEN v6 0/8] " Ian Campbell
` (2 preceding siblings ...)
2015-12-03 11:23 ` [Qemu-devel] [PATCH QEMU-XEN v6 3/8] xen: Switch to libxengnttab " Ian Campbell
@ 2015-12-03 11:23 ` Ian Campbell
2015-12-04 15:26 ` Stefano Stabellini
2015-12-09 13:41 ` Ian Campbell
2015-12-03 11:23 ` [Qemu-devel] [PATCH QEMU-XEN v6 5/8] xen: Switch uses of xc_map_foreign_{pages, bulk} to use libxenforeignmemory API Ian Campbell
` (3 subsequent siblings)
7 siblings, 2 replies; 20+ messages in thread
From: Ian Campbell @ 2015-12-03 11:23 UTC (permalink / raw)
To: ian.jackson, wei.liu2, xen-devel
Cc: Ian Campbell, qemu-devel, stefano.stabellini
In Xen 4.7 we are refactoring parts libxenctrl into a number of
separate libraries which will provide backward and forward API and ABI
compatiblity.
One such library will be libxenforeignmemory which provides access to
privileged foreign mappings and which will provide an interface
equivalent to xc_map_foreign_{pages,bulk}.
In preparation for this switch all uses of xc_map_foreign_range to
xc_map_foreign_pages. This is trivial because size was always
XC_PAGE_SIZE so the necessary adjustments are trivial:
* Pass &mfn (an array of length 1) instead of mfn. The function
takes a pointer to const, so there is no possibily of mfn changing
due to this change.
* Pass nr_pages=1 instead of size=XC_PAGE_SIZE
There is one wrinkle in xen_console.c:con_initialise() where
con->ring_ref is an int but can in some code paths (when !xendev->dev)
be treated as an mfn. I think this is an existing latent truncation
hazard on platforms where xen_pfn_t is 64-bit and int is 32-bit (e.g.
amd64, both arm* variants). I'm unsure under what circumstances
xendev->dev can be NULL or if anything elsewhere ensures the value
fits into an int. For now I just use a temporary xen_pfn_t to in
effect upcast the pointer from int* to xen_pfn_t*.
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
---
v6: Switch to xc_map_foreign_pages rather than _bulk. Switching to
_bulk without checking the value of err[0] risked missing errors.
The new xenforeignmemory_map coming later in this series will
DTRT with err==NULL.
Dropped Stefano's Reviewed-by due to this change.
v4: Ran checkpatch, fixed all errors
Mention the const-ness of the mfn array in the commit log
---
hw/char/xen_console.c | 8 ++++----
hw/display/xenfb.c | 5 ++---
xen-hvm.c | 14 +++++++-------
3 files changed, 13 insertions(+), 14 deletions(-)
diff --git a/hw/char/xen_console.c b/hw/char/xen_console.c
index 8c06c19..56f1b1a 100644
--- a/hw/char/xen_console.c
+++ b/hw/char/xen_console.c
@@ -228,10 +228,10 @@ static int con_initialise(struct XenDevice *xendev)
con->buffer.max_capacity = limit;
if (!xendev->dev) {
- con->sring = xc_map_foreign_range(xen_xc, con->xendev.dom,
- XC_PAGE_SIZE,
- PROT_READ|PROT_WRITE,
- con->ring_ref);
+ xen_pfn_t mfn = con->ring_ref;
+ con->sring = xc_map_foreign_pages(xen_xc, con->xendev.dom,
+ PROT_READ|PROT_WRITE,
+ &mfn, 1);
} else {
con->sring = xengnttab_map_grant_ref(xendev->gnttabdev, con->xendev.dom,
con->ring_ref,
diff --git a/hw/display/xenfb.c b/hw/display/xenfb.c
index 5e324ef..c96d974 100644
--- a/hw/display/xenfb.c
+++ b/hw/display/xenfb.c
@@ -104,9 +104,8 @@ static int common_bind(struct common *c)
if (xenstore_read_fe_int(&c->xendev, "event-channel", &c->xendev.remote_port) == -1)
return -1;
- c->page = xc_map_foreign_range(xen_xc, c->xendev.dom,
- XC_PAGE_SIZE,
- PROT_READ | PROT_WRITE, mfn);
+ c->page = xc_map_foreign_pages(xen_xc, c->xendev.dom,
+ PROT_READ | PROT_WRITE, &mfn, 1);
if (c->page == NULL)
return -1;
diff --git a/xen-hvm.c b/xen-hvm.c
index 6680782..2f4e109 100644
--- a/xen-hvm.c
+++ b/xen-hvm.c
@@ -1240,8 +1240,9 @@ int xen_hvm_init(PCMachineState *pcms,
DPRINTF("buffered io page at pfn %lx\n", bufioreq_pfn);
DPRINTF("buffered io evtchn is %x\n", bufioreq_evtchn);
- state->shared_page = xc_map_foreign_range(xen_xc, xen_domid, XC_PAGE_SIZE,
- PROT_READ|PROT_WRITE, ioreq_pfn);
+ state->shared_page = xc_map_foreign_pages(xen_xc, xen_domid,
+ PROT_READ|PROT_WRITE,
+ &ioreq_pfn, 1);
if (state->shared_page == NULL) {
hw_error("map shared IO page returned error %d handle=" XC_INTERFACE_FMT,
errno, xen_xc);
@@ -1251,8 +1252,8 @@ int xen_hvm_init(PCMachineState *pcms,
if (!rc) {
DPRINTF("shared vmport page at pfn %lx\n", ioreq_pfn);
state->shared_vmport_page =
- xc_map_foreign_range(xen_xc, xen_domid, XC_PAGE_SIZE,
- PROT_READ|PROT_WRITE, ioreq_pfn);
+ xc_map_foreign_pages(xen_xc, xen_domid, PROT_READ|PROT_WRITE,
+ &ioreq_pfn, 1);
if (state->shared_vmport_page == NULL) {
hw_error("map shared vmport IO page returned error %d handle="
XC_INTERFACE_FMT, errno, xen_xc);
@@ -1261,10 +1262,9 @@ int xen_hvm_init(PCMachineState *pcms,
hw_error("get vmport regs pfn returned error %d, rc=%d", errno, rc);
}
- state->buffered_io_page = xc_map_foreign_range(xen_xc, xen_domid,
- XC_PAGE_SIZE,
+ state->buffered_io_page = xc_map_foreign_pages(xen_xc, xen_domid,
PROT_READ|PROT_WRITE,
- bufioreq_pfn);
+ &bufioreq_pfn, 1);
if (state->buffered_io_page == NULL) {
hw_error("map buffered IO page returned error %d", errno);
}
--
2.1.4
^ permalink raw reply related [flat|nested] 20+ messages in thread
* [Qemu-devel] [PATCH QEMU-XEN v6 5/8] xen: Switch uses of xc_map_foreign_{pages, bulk} to use libxenforeignmemory API.
2015-12-03 11:23 ` [Qemu-devel] [PATCH QEMU-XEN v6 0/8] " Ian Campbell
` (3 preceding siblings ...)
2015-12-03 11:23 ` [Qemu-devel] [PATCH QEMU-XEN v6 4/8] xen: Switch uses of xc_map_foreign_range into xc_map_foreign_pages Ian Campbell
@ 2015-12-03 11:23 ` Ian Campbell
2015-12-04 15:26 ` Stefano Stabellini
2015-12-03 11:23 ` [Qemu-devel] [PATCH QEMU-XEN v6 6/8] xen: Use stable library interfaces when they are available Ian Campbell
` (2 subsequent siblings)
7 siblings, 1 reply; 20+ messages in thread
From: Ian Campbell @ 2015-12-03 11:23 UTC (permalink / raw)
To: ian.jackson, wei.liu2, xen-devel
Cc: Ian Campbell, qemu-devel, stefano.stabellini
In Xen 4.7 we are refactoring parts libxenctrl into a number of
separate libraries which will provide backward and forward API and ABI
compatiblity.
One such library will be libxenforeignmemory which provides access to
privileged foreign mappings and which will provide an interface
equivalent to xc_map_foreign_{pages,bulk}.
The new xenforeignmemory_map() function behaves like
xc_map_foreign_pages() when the err argument is NULL and like
xc_map_foreign_bulk() when err is non-NULL, which maps into the shim
here onto checking err == NULL and calling the appropriate old
function.
Note that xenforeignmemory_map() takes the number of pages before the
arrays themselves, in order to support potentially future use of
variable-length-arrays in the prototype (in the future, when Xen's
baseline toolchain requirements are new enough to ensure VLAs are
supported).
In preparation for adding support for libxenforeignmemory add support
to the <=4.0 and <=4.6 compat code in xen_common.h to allow us to
switch to using the new API. These shims will disappear for versions
of Xen which include libxenforeignmemory.
Since libxenforeignmemory will have its own handle type but for <= 4.6
the functionality is provided by using a libxenctrl handle we
introduce a new global xen_fmem alongside the existing xen_xc. In fact
we make xen_fmem a pointer to the existing xen_xc, which then works
correctly with both <=4.0 (xc handle is an int) and <=4.6 (xc handle
is a pointer). In the latter case xen_fmem is actually a double
indirect pointer, but it all falls out in the wash.
Unlike libxenctrl libxenforeignmemory has an explicit unmap function,
rather than just specifying that munmap should be used, so the unmap
paths are updated to use xenforeignmemory_unmap, which is a shim for
munmap on these versions of xen. The mappings in xen-hvm.c do not
appear to be unmapped (which makes sense for a qemu-dm process)
In fb_disconnect this results in a change from simply mmap over the
existing mapping (with an implicit munmap) to expliclty unmapping with
xenforeignmemory_unmap and then mapping the required anonymous memory
in the same hole. I don't think this is a problem since any other
thread which was racily touching this region would already be running
the risk of hitting the mapping halfway through the call. If this is
thought to be a problem then we could consider adding an extra API to
the libxenforeignmemory interface to replace a foreign mapping with
anonymous shared memory, but I'd prefer not to.
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
---
v6: Handle _pages as well as _bulk, due to changes in the previous
patches, including the dropping of "xen: Switch uses of
xc_map_foreign_pages into xc_map_foreign_bulk" which previous preceded
this patch and the change of "xen: Switch uses of
xc_map_foreign_range into xc_map_foreign_bulk" into "xen: Switch
uses of xc_map_foreign_range into xc_map_foreign_pages".
Handle reordering of arguments to xenforeignmemory_map().
Dropped Stefano's Reviewed-by due to these changes.
v4: Rebase onto "xen_console: correctly cleanup primary console on
teardown."
xenforeignmemory_unmap takes pages not bytes
Compat wrapper for xenforeignmemory_open instead of ifdef in code.
Run check patch and fix most issues. I did not fix:
ERROR: do not initialise globals to 0 or NULL
+xenforeignmemory_handle *xen_fmem = NULL;
=> This is consistent with all of the existing declarations.
ERROR: need consistent spacing around '*' (ctx:WxV)
+typedef xc_interface *xenforeignmemory_handle;
=> I think this is a false +ve since this is a pointer "*" not a multiple "*".
reorder args to xenforeignmemory_map
---
hw/char/xen_console.c | 8 ++++----
hw/display/xenfb.c | 17 +++++++++--------
hw/xen/xen_backend.c | 3 ++-
include/hw/xen/xen_backend.h | 1 +
include/hw/xen/xen_common.h | 29 +++++++++++++++++++++++++++++
xen-common.c | 6 ++++++
xen-hvm.c | 12 ++++++------
xen-mapcache.c | 6 +++---
8 files changed, 60 insertions(+), 22 deletions(-)
diff --git a/hw/char/xen_console.c b/hw/char/xen_console.c
index 56f1b1a..788dd31 100644
--- a/hw/char/xen_console.c
+++ b/hw/char/xen_console.c
@@ -229,9 +229,9 @@ static int con_initialise(struct XenDevice *xendev)
if (!xendev->dev) {
xen_pfn_t mfn = con->ring_ref;
- con->sring = xc_map_foreign_pages(xen_xc, con->xendev.dom,
- PROT_READ|PROT_WRITE,
- &mfn, 1);
+ con->sring = xenforeignmemory_map(xen_fmem, con->xendev.dom,
+ PROT_READ|PROT_WRITE,
+ 1, &mfn, NULL);
} else {
con->sring = xengnttab_map_grant_ref(xendev->gnttabdev, con->xendev.dom,
con->ring_ref,
@@ -273,7 +273,7 @@ static void con_disconnect(struct XenDevice *xendev)
if (con->sring) {
if (!xendev->dev) {
- munmap(con->sring, XC_PAGE_SIZE);
+ xenforeignmemory_unmap(xen_fmem, con->sring, 1);
} else {
xengnttab_munmap(xendev->gnttabdev, con->sring, 1);
}
diff --git a/hw/display/xenfb.c b/hw/display/xenfb.c
index c96d974..8b86b4a 100644
--- a/hw/display/xenfb.c
+++ b/hw/display/xenfb.c
@@ -104,8 +104,8 @@ static int common_bind(struct common *c)
if (xenstore_read_fe_int(&c->xendev, "event-channel", &c->xendev.remote_port) == -1)
return -1;
- c->page = xc_map_foreign_pages(xen_xc, c->xendev.dom,
- PROT_READ | PROT_WRITE, &mfn, 1);
+ c->page = xenforeignmemory_map(xen_fmem, c->xendev.dom,
+ PROT_READ | PROT_WRITE, 1, &mfn, NULL);
if (c->page == NULL)
return -1;
@@ -120,7 +120,7 @@ static void common_unbind(struct common *c)
{
xen_be_unbind_evtchn(&c->xendev);
if (c->page) {
- munmap(c->page, XC_PAGE_SIZE);
+ xenforeignmemory_unmap(xen_fmem, c->page, 1);
c->page = NULL;
}
}
@@ -493,15 +493,15 @@ static int xenfb_map_fb(struct XenFB *xenfb)
fbmfns = g_malloc0(sizeof(xen_pfn_t) * xenfb->fbpages);
xenfb_copy_mfns(mode, n_fbdirs, pgmfns, pd);
- map = xc_map_foreign_pages(xen_xc, xenfb->c.xendev.dom,
- PROT_READ, pgmfns, n_fbdirs);
+ map = xenforeignmemory_map(xen_fmem, xenfb->c.xendev.dom,
+ PROT_READ, n_fbdirs, pgmfns, NULL);
if (map == NULL)
goto out;
xenfb_copy_mfns(mode, xenfb->fbpages, fbmfns, map);
- munmap(map, n_fbdirs * XC_PAGE_SIZE);
+ xenforeignmemory_unmap(xen_fmem, map, n_fbdirs);
- xenfb->pixels = xc_map_foreign_pages(xen_xc, xenfb->c.xendev.dom,
- PROT_READ, fbmfns, xenfb->fbpages);
+ xenfb->pixels = xenforeignmemory_map(xen_fmem, xenfb->c.xendev.dom,
+ PROT_READ, xenfb->fbpages, fbmfns, NULL);
if (xenfb->pixels == NULL)
goto out;
@@ -908,6 +908,7 @@ static void fb_disconnect(struct XenDevice *xendev)
* Replacing the framebuffer with anonymous shared memory
* instead. This releases the guest pages and keeps qemu happy.
*/
+ xenforeignmemory_unmap(xen_fmem, fb->pixels, fb->fbpages);
fb->pixels = mmap(fb->pixels, fb->fbpages * XC_PAGE_SIZE,
PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANON,
-1, 0);
diff --git a/hw/xen/xen_backend.c b/hw/xen/xen_backend.c
index 966e34f..caa459c 100644
--- a/hw/xen/xen_backend.c
+++ b/hw/xen/xen_backend.c
@@ -45,6 +45,7 @@
/* public */
XenXC xen_xc = XC_HANDLER_INITIAL_VALUE;
+xenforeignmemory_handle *xen_fmem = NULL;
struct xs_handle *xenstore = NULL;
const char *xen_protocol;
@@ -717,7 +718,7 @@ int xen_be_init(void)
qemu_set_fd_handler(xs_fileno(xenstore), xenstore_update, NULL, NULL);
- if (xen_xc == XC_HANDLER_INITIAL_VALUE) {
+ if (xen_xc == XC_HANDLER_INITIAL_VALUE || xen_fmem == NULL) {
/* Check if xen_init() have been called */
goto err;
}
diff --git a/include/hw/xen/xen_backend.h b/include/hw/xen/xen_backend.h
index 8e8857b..e0d52ee 100644
--- a/include/hw/xen/xen_backend.h
+++ b/include/hw/xen/xen_backend.h
@@ -57,6 +57,7 @@ struct XenDevice {
/* variables */
extern XenXC xen_xc;
+extern xenforeignmemory_handle *xen_fmem;
extern struct xs_handle *xenstore;
extern const char *xen_protocol;
diff --git a/include/hw/xen/xen_common.h b/include/hw/xen/xen_common.h
index 2cadd4f..8fbaf07 100644
--- a/include/hw/xen/xen_common.h
+++ b/include/hw/xen/xen_common.h
@@ -41,6 +41,7 @@ static inline void *xc_map_foreign_bulk(int xc_handle, uint32_t dom, int prot,
typedef int XenXC;
typedef int xenevtchn_handle;
typedef int xengnttab_handle;
+typedef int xenforeignmemory_handle;
# define XC_INTERFACE_FMT "%i"
# define XC_HANDLER_INITIAL_VALUE -1
@@ -104,6 +105,19 @@ static inline XenXC xen_xc_interface_open(void *logger, void *dombuild_logger,
return xc_interface_open();
}
+#define xenforeignmemory_open(l, f) &xen_xc
+static inline void *xenforeignmemory_map(XenXC *h, uint32_t dom,
+ int prot, size_t pages,
+ const xen_pfn_t arr[/*pages*/],
+ int err[/*pages*/])
+{
+ if (err)
+ return xc_map_foreign_bulk(*h, dom, prot, arr, err, pages);
+ else
+ return xc_map_foreign_pages(*h, dom, prot, arr, pages);
+}
+#define xenforeignmemory_unmap(h, p, s) munmap(p, s * XC_PAGE_SIZE)
+
static inline int xc_fd(int xen_xc)
{
return xen_xc;
@@ -149,6 +163,7 @@ static inline void xs_close(struct xs_handle *xsh)
#else
typedef xc_interface *XenXC;
+typedef xc_interface *xenforeignmemory_handle;
typedef xc_evtchn xenevtchn_handle;
typedef xc_gnttab xengnttab_handle;
@@ -178,6 +193,20 @@ static inline XenXC xen_xc_interface_open(void *logger, void *dombuild_logger,
return xc_interface_open(logger, dombuild_logger, open_flags);
}
+#define xenforeignmemory_open(l, f) &xen_xc
+static inline void *xenforeignmemory_map(XenXC *h, uint32_t dom,
+ int prot, size_t pages,
+ const xen_pfn_t arr[/*pages*/],
+ int err[/*pages*/])
+{
+ if (err)
+ return xc_map_foreign_bulk(*h, dom, prot, arr, err, pages);
+ else
+ return xc_map_foreign_pages(*h, dom, prot, arr, pages);
+}
+
+#define xenforeignmemory_unmap(h, p, s) munmap(p, s * XC_PAGE_SIZE)
+
/* FIXME There is now way to have the xen fd */
static inline int xc_fd(xc_interface *xen_xc)
{
diff --git a/xen-common.c b/xen-common.c
index 0dcdbc3..6cd2959 100644
--- a/xen-common.c
+++ b/xen-common.c
@@ -118,6 +118,12 @@ static int xen_init(MachineState *ms)
xen_be_printf(NULL, 0, "can't open xen interface\n");
return -1;
}
+ xen_fmem = xenforeignmemory_open(0, 0);
+ if (xen_fmem == NULL) {
+ xen_be_printf(NULL, 0, "can't open xen fmem interface\n");
+ xc_interface_close(xen_xc);
+ return -1;
+ }
qemu_add_vm_change_state_handler(xen_change_state_handler, NULL);
global_state_set_optional();
diff --git a/xen-hvm.c b/xen-hvm.c
index 2f4e109..c64f4b0 100644
--- a/xen-hvm.c
+++ b/xen-hvm.c
@@ -1240,9 +1240,9 @@ int xen_hvm_init(PCMachineState *pcms,
DPRINTF("buffered io page at pfn %lx\n", bufioreq_pfn);
DPRINTF("buffered io evtchn is %x\n", bufioreq_evtchn);
- state->shared_page = xc_map_foreign_pages(xen_xc, xen_domid,
+ state->shared_page = xenforeignmemory_map(xen_fmem, xen_domid,
PROT_READ|PROT_WRITE,
- &ioreq_pfn, 1);
+ 1, &ioreq_pfn, NULL);
if (state->shared_page == NULL) {
hw_error("map shared IO page returned error %d handle=" XC_INTERFACE_FMT,
errno, xen_xc);
@@ -1252,8 +1252,8 @@ int xen_hvm_init(PCMachineState *pcms,
if (!rc) {
DPRINTF("shared vmport page at pfn %lx\n", ioreq_pfn);
state->shared_vmport_page =
- xc_map_foreign_pages(xen_xc, xen_domid, PROT_READ|PROT_WRITE,
- &ioreq_pfn, 1);
+ xenforeignmemory_map(xen_fmem, xen_domid, PROT_READ|PROT_WRITE,
+ 1, &ioreq_pfn, NULL);
if (state->shared_vmport_page == NULL) {
hw_error("map shared vmport IO page returned error %d handle="
XC_INTERFACE_FMT, errno, xen_xc);
@@ -1262,9 +1262,9 @@ int xen_hvm_init(PCMachineState *pcms,
hw_error("get vmport regs pfn returned error %d, rc=%d", errno, rc);
}
- state->buffered_io_page = xc_map_foreign_pages(xen_xc, xen_domid,
+ state->buffered_io_page = xenforeignmemory_map(xen_fmem, xen_domid,
PROT_READ|PROT_WRITE,
- &bufioreq_pfn, 1);
+ 1, &bufioreq_pfn, NULL);
if (state->buffered_io_page == NULL) {
hw_error("map buffered IO page returned error %d", errno);
}
diff --git a/xen-mapcache.c b/xen-mapcache.c
index 97fece2..4a04378 100644
--- a/xen-mapcache.c
+++ b/xen-mapcache.c
@@ -176,10 +176,10 @@ static void xen_remap_bucket(MapCacheEntry *entry,
pfns[i] = (address_index << (MCACHE_BUCKET_SHIFT-XC_PAGE_SHIFT)) + i;
}
- vaddr_base = xc_map_foreign_bulk(xen_xc, xen_domid, PROT_READ|PROT_WRITE,
- pfns, err, nb_pfn);
+ vaddr_base = xenforeignmemory_map(xen_fmem, xen_domid, PROT_READ|PROT_WRITE,
+ nb_pfn, pfns, err);
if (vaddr_base == NULL) {
- perror("xc_map_foreign_bulk");
+ perror("xenforeignmemory_map");
exit(-1);
}
--
2.1.4
^ permalink raw reply related [flat|nested] 20+ messages in thread
* [Qemu-devel] [PATCH QEMU-XEN v6 6/8] xen: Use stable library interfaces when they are available.
2015-12-03 11:23 ` [Qemu-devel] [PATCH QEMU-XEN v6 0/8] " Ian Campbell
` (4 preceding siblings ...)
2015-12-03 11:23 ` [Qemu-devel] [PATCH QEMU-XEN v6 5/8] xen: Switch uses of xc_map_foreign_{pages, bulk} to use libxenforeignmemory API Ian Campbell
@ 2015-12-03 11:23 ` Ian Campbell
2015-12-04 15:31 ` Stefano Stabellini
2015-12-03 11:23 ` [Qemu-devel] [PATCH QEMU-XEN v6 7/8] xen: domainbuild: reopen libxenctrl interface after forking for domain watcher Ian Campbell
2015-12-03 11:23 ` [Qemu-devel] [PATCH QEMU-XEN v6 8/8] xen: make it possible to build without the Xen PV domain builder Ian Campbell
7 siblings, 1 reply; 20+ messages in thread
From: Ian Campbell @ 2015-12-03 11:23 UTC (permalink / raw)
To: ian.jackson, wei.liu2, xen-devel
Cc: Ian Campbell, qemu-devel, stefano.stabellini
In Xen 4.7 we are refactoring parts libxenctrl into a number of
separate libraries which will provide backward and forward API and ABI
compatiblity.
Specifically libxenevtchn, libxengnttab and libxenforeignmemory.
Previous patches have already laid the groundwork for using these by
switching the existing compatibility shims to reflect the intefaces to
these libraries.
So all which remains is to update configure to detect the libraries
and enable their use. Although they are notionally independent we take
an all or nothing approach to the three libraries since they were
added at the same time.
The only non-obvious bit is that we now open a proper xenforeignmemory
handle for xen_fmem instead of reusing the xen_xc handle.
Build tested with 4.0 .. 4.6 (inclusive) and the patches targetting
4.7 which adds these libraries.
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
---
v6: Two minor formatting things.
Rebase onto "xen: fix usage of xc_domain_create in domain
builder", required adjusting the configure script changes.
The rebase wasn't entirely trivial (semantically), so dropped
Stefano's reviwed by.
v5: Remove ifdef check when undeffing the compat stuff.
s/now way/no way/
v4: xenforeignmemory_open is now a compat wrapper, so no ifdef.
Simplify configury by asserting that interface version 470 will
always have the libraries (lack of them makes it 460).
Ran checkpatch and fixed everything except:
ERROR: need consistent spacing around '*' (ctx:WxV)
+typedef xc_interface *XenXC;
Which I think is a false +ve.
Simpler configure stuff
---
configure | 42 +++++++++++++++++++++++++++++++++++++++++-
include/hw/xen/xen_common.h | 35 +++++++++++++++++++++++++++++++++--
2 files changed, 74 insertions(+), 3 deletions(-)
diff --git a/configure b/configure
index 979bc55..cb72115 100755
--- a/configure
+++ b/configure
@@ -1923,6 +1923,7 @@ fi
if test "$xen" != "no" ; then
xen_libs="-lxenstore -lxenctrl -lxenguest"
+ xen_stable_libs="-lxenforeignmemory -lxengnttab -lxenevtchn"
# First we test whether Xen headers and libraries are available.
# If no, we are done and there is no Xen support.
@@ -1945,16 +1946,52 @@ EOF
# Xen unstable
elif
cat > $TMPC <<EOF &&
+/*
+ * If we have stable libs the we don't want the libxc compat
+ * layers, regardless of what CFLAGS we may have been given.
+ */
+#undef XC_WANT_COMPAT_EVTCHN_API
+#undef XC_WANT_COMPAT_GNTTAB_API
+#undef XC_WANT_COMPAT_MAP_FOREIGN_API
#include <xenctrl.h>
+#include <xenstore.h>
+#include <xenevtchn.h>
+#include <xengnttab.h>
+#include <xenforeignmemory.h>
#include <stdint.h>
+#include <xen/hvm/hvm_info_table.h>
+#if !defined(HVM_MAX_VCPUS)
+# error HVM_MAX_VCPUS not defined
+#endif
int main(void) {
xc_interface *xc = NULL;
+ xenforeignmemory_handle *xfmem;
+ xenevtchn_handle *xe;
+ xengnttab_handle *xg;
xen_domain_handle_t handle;
+
+ xs_daemon_open();
+
+ xc = xc_interface_open(0, 0, 0);
+ xc_hvm_set_mem_type(0, 0, HVMMEM_ram_ro, 0, 0);
+ xc_domain_add_to_physmap(0, 0, XENMAPSPACE_gmfn, 0, 0);
+ xc_hvm_inject_msi(xc, 0, 0xf0000000, 0x00000000);
+ xc_hvm_create_ioreq_server(xc, 0, HVM_IOREQSRV_BUFIOREQ_ATOMIC, NULL);
xc_domain_create(xc, 0, handle, 0, NULL, NULL);
+
+ xfmem = xenforeignmemory_open(0, 0);
+ xenforeignmemory_map(xfmem, 0, 0, 0, 0, 0);
+
+ xe = xenevtchn_open(0, 0);
+ xenevtchn_fd(xe);
+
+ xg = xengnttab_open(0, 0);
+ xengnttab_map_grant_ref(xg, 0, 0, 0);
+
return 0;
}
EOF
- compile_prog "" "$xen_libs"
+ compile_prog "" "$xen_libs $xen_stable_libs"
then
xen_ctrl_version=470
xen=yes
@@ -2138,6 +2175,9 @@ EOF
fi
if test "$xen" = yes; then
+ if test $xen_ctrl_version -ge 470 ; then
+ libs_softmmu="$xen_stable_libs $libs_softmmu"
+ fi
libs_softmmu="$xen_libs $libs_softmmu"
fi
fi
diff --git a/include/hw/xen/xen_common.h b/include/hw/xen/xen_common.h
index 8fbaf07..884fbd1 100644
--- a/include/hw/xen/xen_common.h
+++ b/include/hw/xen/xen_common.h
@@ -6,6 +6,15 @@
#include <stddef.h>
#include <inttypes.h>
+/*
+ * If we have new enough libxenctrl then we do not want/need these compat
+ * interfaces, despite what the user supplied cflags might say. They
+ * must be undefined before including xenctrl.h
+ */
+#undef XC_WANT_COMPAT_EVTCHN_API
+#undef XC_WANT_COMPAT_GNTTAB_API
+#undef XC_WANT_COMPAT_MAP_FOREIGN_API
+
#include <xenctrl.h>
#if CONFIG_XEN_CTRL_INTERFACE_VERSION < 420
# include <xs.h>
@@ -159,8 +168,8 @@ static inline void xs_close(struct xs_handle *xsh)
}
-/* Xen 4.1 */
-#else
+/* Xen 4.1 thru 4.6 */
+#elif CONFIG_XEN_CTRL_INTERFACE_VERSION < 470
typedef xc_interface *XenXC;
typedef xc_interface *xenforeignmemory_handle;
@@ -207,6 +216,28 @@ static inline void *xenforeignmemory_map(XenXC *h, uint32_t dom,
#define xenforeignmemory_unmap(h, p, s) munmap(p, s * XC_PAGE_SIZE)
+/* FIXME There is no way to have the xen fd */
+static inline int xc_fd(xc_interface *xen_xc)
+{
+ return -1;
+}
+#else /* CONFIG_XEN_CTRL_INTERFACE_VERSION >= 470 */
+
+typedef xc_interface *XenXC;
+
+# define XC_INTERFACE_FMT "%p"
+# define XC_HANDLER_INITIAL_VALUE NULL
+
+#include <xenevtchn.h>
+#include <xengnttab.h>
+#include <xenforeignmemory.h>
+
+static inline XenXC xen_xc_interface_open(void *logger, void *dombuild_logger,
+ unsigned int open_flags)
+{
+ return xc_interface_open(logger, dombuild_logger, open_flags);
+}
+
/* FIXME There is now way to have the xen fd */
static inline int xc_fd(xc_interface *xen_xc)
{
--
2.1.4
^ permalink raw reply related [flat|nested] 20+ messages in thread
* [Qemu-devel] [PATCH QEMU-XEN v6 7/8] xen: domainbuild: reopen libxenctrl interface after forking for domain watcher.
2015-12-03 11:23 ` [Qemu-devel] [PATCH QEMU-XEN v6 0/8] " Ian Campbell
` (5 preceding siblings ...)
2015-12-03 11:23 ` [Qemu-devel] [PATCH QEMU-XEN v6 6/8] xen: Use stable library interfaces when they are available Ian Campbell
@ 2015-12-03 11:23 ` Ian Campbell
2015-12-03 11:23 ` [Qemu-devel] [PATCH QEMU-XEN v6 8/8] xen: make it possible to build without the Xen PV domain builder Ian Campbell
7 siblings, 0 replies; 20+ messages in thread
From: Ian Campbell @ 2015-12-03 11:23 UTC (permalink / raw)
To: ian.jackson, wei.liu2, xen-devel
Cc: Ian Campbell, qemu-devel, stefano.stabellini
Using an existing libxenctrl handle after a fork was never
particularly safe (especially if foreign mappings existed at the time
of the fork) and the xc fd has been unavailable for many releases.
Reopen the handle after fork and therefore do away with xc_fd().
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
---
The fact that xc_fd hasn't been useful since at least Xen 4.1 makes me
question the utility of this domainbuild in QEMU. Perhaps we should
just nuke it?
---
hw/xenpv/xen_domainbuild.c | 9 ++++++---
include/hw/xen/xen_common.h | 17 -----------------
2 files changed, 6 insertions(+), 20 deletions(-)
diff --git a/hw/xenpv/xen_domainbuild.c b/hw/xenpv/xen_domainbuild.c
index ac0e5ac..f9be029 100644
--- a/hw/xenpv/xen_domainbuild.c
+++ b/hw/xenpv/xen_domainbuild.c
@@ -174,12 +174,15 @@ static int xen_domain_watcher(void)
for (i = 3; i < n; i++) {
if (i == fd[0])
continue;
- if (i == xc_fd(xen_xc)) {
- continue;
- }
close(i);
}
+ /*
+ * Reopen xc interface, since the original is unsafe after fork
+ * and was closed above.
+ */
+ xen_xc = xc_interface_open(0, 0, 0);
+
/* ignore term signals */
signal(SIGINT, SIG_IGN);
signal(SIGTERM, SIG_IGN);
diff --git a/include/hw/xen/xen_common.h b/include/hw/xen/xen_common.h
index 884fbd1..206c188 100644
--- a/include/hw/xen/xen_common.h
+++ b/include/hw/xen/xen_common.h
@@ -127,12 +127,6 @@ static inline void *xenforeignmemory_map(XenXC *h, uint32_t dom,
}
#define xenforeignmemory_unmap(h, p, s) munmap(p, s * XC_PAGE_SIZE)
-static inline int xc_fd(int xen_xc)
-{
- return xen_xc;
-}
-
-
static inline int xc_domain_populate_physmap_exact
(XenXC xc_handle, uint32_t domid, unsigned long nr_extents,
unsigned int extent_order, unsigned int mem_flags, xen_pfn_t *extent_start)
@@ -216,11 +210,6 @@ static inline void *xenforeignmemory_map(XenXC *h, uint32_t dom,
#define xenforeignmemory_unmap(h, p, s) munmap(p, s * XC_PAGE_SIZE)
-/* FIXME There is no way to have the xen fd */
-static inline int xc_fd(xc_interface *xen_xc)
-{
- return -1;
-}
#else /* CONFIG_XEN_CTRL_INTERFACE_VERSION >= 470 */
typedef xc_interface *XenXC;
@@ -237,12 +226,6 @@ static inline XenXC xen_xc_interface_open(void *logger, void *dombuild_logger,
{
return xc_interface_open(logger, dombuild_logger, open_flags);
}
-
-/* FIXME There is now way to have the xen fd */
-static inline int xc_fd(xc_interface *xen_xc)
-{
- return -1;
-}
#endif
/* Xen before 4.2 */
--
2.1.4
^ permalink raw reply related [flat|nested] 20+ messages in thread
* [Qemu-devel] [PATCH QEMU-XEN v6 8/8] xen: make it possible to build without the Xen PV domain builder
2015-12-03 11:23 ` [Qemu-devel] [PATCH QEMU-XEN v6 0/8] " Ian Campbell
` (6 preceding siblings ...)
2015-12-03 11:23 ` [Qemu-devel] [PATCH QEMU-XEN v6 7/8] xen: domainbuild: reopen libxenctrl interface after forking for domain watcher Ian Campbell
@ 2015-12-03 11:23 ` Ian Campbell
7 siblings, 0 replies; 20+ messages in thread
From: Ian Campbell @ 2015-12-03 11:23 UTC (permalink / raw)
To: ian.jackson, wei.liu2, xen-devel
Cc: Ian Campbell, qemu-devel, stefano.stabellini
Until the previous patch this relied on xc_fd(), which was only
implemented for Xen 4.0 and earlier.
Given this wasn't working since Xen 4.0 I have marked this as disabled
by default.
Removing this support drops the use of a bunch of symbols from
libxenctrl, specifically:
- xc_domain_create
- xc_domain_destroy
- xc_domain_getinfo
- xc_domain_max_vcpus
- xc_domain_setmaxmem
- xc_domain_unpause
- xc_evtchn_alloc_unbound
- xc_linux_build
This is another step towards only using Xen libraries which provide a
stable inteface.
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Reviewed-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
---
v6: Rebase onto "xen: fix usage of xc_domain_create in domain
builder" (trivial, Reviewed-by retained)
v5: XEN_CREATE entirely wihtin CONFIG_XEN_PV_DOMAIN_BUILD ifdef.
Simplify configure'ry.
v4: Fixed all checkpatch errors.
Disabled by default.
---
configure | 15 +++++++++++++++
hw/xenpv/Makefile.objs | 4 +++-
hw/xenpv/xen_machine_pv.c | 15 +++++++++++----
include/hw/xen/xen_common.h | 4 ++++
4 files changed, 33 insertions(+), 5 deletions(-)
diff --git a/configure b/configure
index cb72115..1d27289 100755
--- a/configure
+++ b/configure
@@ -250,6 +250,7 @@ vnc_jpeg=""
vnc_png=""
xen=""
xen_ctrl_version=""
+xen_pv_domain_build="no"
xen_pci_passthrough=""
linux_aio=""
cap_ng=""
@@ -925,6 +926,10 @@ for opt do
;;
--enable-xen-pci-passthrough) xen_pci_passthrough="yes"
;;
+ --disable-xen-pv-domain-build) xen_pv_domain_build="no"
+ ;;
+ --enable-xen-pv-domain-build) xen_pv_domain_build="yes"
+ ;;
--disable-brlapi) brlapi="no"
;;
--enable-brlapi) brlapi="yes"
@@ -2199,6 +2204,12 @@ if test "$xen_pci_passthrough" != "no"; then
fi
fi
+if test "$xen_pv_domain_build" = "yes" &&
+ test "$xen" != "yes"; then
+ error_exit "User requested Xen PV domain builder support" \
+ "which requires Xen support."
+fi
+
##########################################
# libtool probe
@@ -4806,6 +4817,7 @@ fi
echo "xen support $xen"
if test "$xen" = "yes" ; then
echo "xen ctrl version $xen_ctrl_version"
+ echo "pv dom build $xen_pv_domain_build"
fi
echo "brlapi support $brlapi"
echo "bluez support $bluez"
@@ -5174,6 +5186,9 @@ fi
if test "$xen" = "yes" ; then
echo "CONFIG_XEN_BACKEND=y" >> $config_host_mak
echo "CONFIG_XEN_CTRL_INTERFACE_VERSION=$xen_ctrl_version" >> $config_host_mak
+ if test "$xen_pv_domain_build" = "yes" ; then
+ echo "CONFIG_XEN_PV_DOMAIN_BUILD=y" >> $config_host_mak
+ fi
fi
if test "$linux_aio" = "yes" ; then
echo "CONFIG_LINUX_AIO=y" >> $config_host_mak
diff --git a/hw/xenpv/Makefile.objs b/hw/xenpv/Makefile.objs
index 49f6e9e..bbf5873 100644
--- a/hw/xenpv/Makefile.objs
+++ b/hw/xenpv/Makefile.objs
@@ -1,2 +1,4 @@
# Xen PV machine support
-obj-$(CONFIG_XEN) += xen_domainbuild.o xen_machine_pv.o
+obj-$(CONFIG_XEN) += xen_machine_pv.o
+# Xen PV machine builder support
+obj-$(CONFIG_XEN_PV_DOMAIN_BUILD) += xen_domainbuild.o
diff --git a/hw/xenpv/xen_machine_pv.c b/hw/xenpv/xen_machine_pv.c
index 23d6ef0..3250b94 100644
--- a/hw/xenpv/xen_machine_pv.c
+++ b/hw/xenpv/xen_machine_pv.c
@@ -30,9 +30,6 @@
static void xen_init_pv(MachineState *machine)
{
- const char *kernel_filename = machine->kernel_filename;
- const char *kernel_cmdline = machine->kernel_cmdline;
- const char *initrd_filename = machine->initrd_filename;
DriveInfo *dinfo;
int i;
@@ -46,17 +43,27 @@ static void xen_init_pv(MachineState *machine)
case XEN_ATTACH:
/* nothing to do, xend handles everything */
break;
- case XEN_CREATE:
+#ifdef CONFIG_XEN_PV_DOMAIN_BUILD
+ case XEN_CREATE: {
+ const char *kernel_filename = machine->kernel_filename;
+ const char *kernel_cmdline = machine->kernel_cmdline;
+ const char *initrd_filename = machine->initrd_filename;
if (xen_domain_build_pv(kernel_filename, initrd_filename,
kernel_cmdline) < 0) {
fprintf(stderr, "xen pv domain creation failed\n");
exit(1);
}
break;
+ }
+#endif
case XEN_EMULATE:
fprintf(stderr, "xen emulation not implemented (yet)\n");
exit(1);
break;
+ default:
+ fprintf(stderr, "unhandled xen_mode %d\n", xen_mode);
+ exit(1);
+ break;
}
xen_be_register("console", &xen_console_ops);
diff --git a/include/hw/xen/xen_common.h b/include/hw/xen/xen_common.h
index 206c188..54a9a7f 100644
--- a/include/hw/xen/xen_common.h
+++ b/include/hw/xen/xen_common.h
@@ -528,6 +528,8 @@ static inline int xen_xc_domain_add_to_physmap(XenXC xch, uint32_t domid,
}
#endif
+#ifdef CONFIG_XEN_PV_DOMAIN_BUILD
+
#if CONFIG_XEN_CTRL_INTERFACE_VERSION < 470
static inline int xen_domain_create(XenXC xc, uint32_t ssidref,
xen_domain_handle_t handle, uint32_t flags,
@@ -544,4 +546,6 @@ static inline int xen_domain_create(XenXC xc, uint32_t ssidref,
}
#endif
+#endif
+
#endif /* QEMU_HW_XEN_COMMON_H */
--
2.1.4
^ permalink raw reply related [flat|nested] 20+ messages in thread
* Re: [Qemu-devel] [PATCH QEMU-XEN v6 5/8] xen: Switch uses of xc_map_foreign_{pages, bulk} to use libxenforeignmemory API.
2015-12-03 11:23 ` [Qemu-devel] [PATCH QEMU-XEN v6 5/8] xen: Switch uses of xc_map_foreign_{pages, bulk} to use libxenforeignmemory API Ian Campbell
@ 2015-12-04 15:26 ` Stefano Stabellini
0 siblings, 0 replies; 20+ messages in thread
From: Stefano Stabellini @ 2015-12-04 15:26 UTC (permalink / raw)
To: Ian Campbell
Cc: wei.liu2, stefano.stabellini, ian.jackson, qemu-devel, xen-devel
On Thu, 3 Dec 2015, Ian Campbell wrote:
> diff --git a/include/hw/xen/xen_common.h b/include/hw/xen/xen_common.h
> index 2cadd4f..8fbaf07 100644
> --- a/include/hw/xen/xen_common.h
> +++ b/include/hw/xen/xen_common.h
> @@ -41,6 +41,7 @@ static inline void *xc_map_foreign_bulk(int xc_handle, uint32_t dom, int prot,
> typedef int XenXC;
> typedef int xenevtchn_handle;
> typedef int xengnttab_handle;
> +typedef int xenforeignmemory_handle;
>
> # define XC_INTERFACE_FMT "%i"
> # define XC_HANDLER_INITIAL_VALUE -1
> @@ -104,6 +105,19 @@ static inline XenXC xen_xc_interface_open(void *logger, void *dombuild_logger,
> return xc_interface_open();
> }
>
> +#define xenforeignmemory_open(l, f) &xen_xc
> +static inline void *xenforeignmemory_map(XenXC *h, uint32_t dom,
> + int prot, size_t pages,
> + const xen_pfn_t arr[/*pages*/],
> + int err[/*pages*/])
> +{
> + if (err)
> + return xc_map_foreign_bulk(*h, dom, prot, arr, err, pages);
> + else
> + return xc_map_foreign_pages(*h, dom, prot, arr, pages);
> +}
> +#define xenforeignmemory_unmap(h, p, s) munmap(p, s * XC_PAGE_SIZE)
> +
> static inline int xc_fd(int xen_xc)
> {
> return xen_xc;
> @@ -149,6 +163,7 @@ static inline void xs_close(struct xs_handle *xsh)
> #else
>
> typedef xc_interface *XenXC;
> +typedef xc_interface *xenforeignmemory_handle;
> typedef xc_evtchn xenevtchn_handle;
> typedef xc_gnttab xengnttab_handle;
>
> @@ -178,6 +193,20 @@ static inline XenXC xen_xc_interface_open(void *logger, void *dombuild_logger,
> return xc_interface_open(logger, dombuild_logger, open_flags);
> }
>
> +#define xenforeignmemory_open(l, f) &xen_xc
> +static inline void *xenforeignmemory_map(XenXC *h, uint32_t dom,
> + int prot, size_t pages,
> + const xen_pfn_t arr[/*pages*/],
> + int err[/*pages*/])
> +{
> + if (err)
> + return xc_map_foreign_bulk(*h, dom, prot, arr, err, pages);
> + else
> + return xc_map_foreign_pages(*h, dom, prot, arr, pages);
> +}
> +
> +#define xenforeignmemory_unmap(h, p, s) munmap(p, s * XC_PAGE_SIZE)
> +
> /* FIXME There is now way to have the xen fd */
> static inline int xc_fd(xc_interface *xen_xc)
> {
The two definitions are the same. Please introduce just one, at the
bottom under the ifdef CONFIG_XEN_CTRL_INTERFACE_VERSION < 470 case.
^ permalink raw reply [flat|nested] 20+ messages in thread
* Re: [Qemu-devel] [PATCH QEMU-XEN v6 4/8] xen: Switch uses of xc_map_foreign_range into xc_map_foreign_pages
2015-12-03 11:23 ` [Qemu-devel] [PATCH QEMU-XEN v6 4/8] xen: Switch uses of xc_map_foreign_range into xc_map_foreign_pages Ian Campbell
@ 2015-12-04 15:26 ` Stefano Stabellini
2015-12-09 13:41 ` Ian Campbell
1 sibling, 0 replies; 20+ messages in thread
From: Stefano Stabellini @ 2015-12-04 15:26 UTC (permalink / raw)
To: Ian Campbell
Cc: wei.liu2, stefano.stabellini, ian.jackson, qemu-devel, xen-devel
On Thu, 3 Dec 2015, Ian Campbell wrote:
> In Xen 4.7 we are refactoring parts libxenctrl into a number of
> separate libraries which will provide backward and forward API and ABI
> compatiblity.
>
> One such library will be libxenforeignmemory which provides access to
> privileged foreign mappings and which will provide an interface
> equivalent to xc_map_foreign_{pages,bulk}.
>
> In preparation for this switch all uses of xc_map_foreign_range to
> xc_map_foreign_pages. This is trivial because size was always
> XC_PAGE_SIZE so the necessary adjustments are trivial:
>
> * Pass &mfn (an array of length 1) instead of mfn. The function
> takes a pointer to const, so there is no possibily of mfn changing
> due to this change.
> * Pass nr_pages=1 instead of size=XC_PAGE_SIZE
>
> There is one wrinkle in xen_console.c:con_initialise() where
> con->ring_ref is an int but can in some code paths (when !xendev->dev)
> be treated as an mfn. I think this is an existing latent truncation
> hazard on platforms where xen_pfn_t is 64-bit and int is 32-bit (e.g.
> amd64, both arm* variants). I'm unsure under what circumstances
> xendev->dev can be NULL or if anything elsewhere ensures the value
> fits into an int. For now I just use a temporary xen_pfn_t to in
> effect upcast the pointer from int* to xen_pfn_t*.
>
> Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Reviewed-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
> v6: Switch to xc_map_foreign_pages rather than _bulk. Switching to
> _bulk without checking the value of err[0] risked missing errors.
> The new xenforeignmemory_map coming later in this series will
> DTRT with err==NULL.
>
> Dropped Stefano's Reviewed-by due to this change.
>
> v4: Ran checkpatch, fixed all errors
> Mention the const-ness of the mfn array in the commit log
> ---
> hw/char/xen_console.c | 8 ++++----
> hw/display/xenfb.c | 5 ++---
> xen-hvm.c | 14 +++++++-------
> 3 files changed, 13 insertions(+), 14 deletions(-)
>
> diff --git a/hw/char/xen_console.c b/hw/char/xen_console.c
> index 8c06c19..56f1b1a 100644
> --- a/hw/char/xen_console.c
> +++ b/hw/char/xen_console.c
> @@ -228,10 +228,10 @@ static int con_initialise(struct XenDevice *xendev)
> con->buffer.max_capacity = limit;
>
> if (!xendev->dev) {
> - con->sring = xc_map_foreign_range(xen_xc, con->xendev.dom,
> - XC_PAGE_SIZE,
> - PROT_READ|PROT_WRITE,
> - con->ring_ref);
> + xen_pfn_t mfn = con->ring_ref;
> + con->sring = xc_map_foreign_pages(xen_xc, con->xendev.dom,
> + PROT_READ|PROT_WRITE,
> + &mfn, 1);
> } else {
> con->sring = xengnttab_map_grant_ref(xendev->gnttabdev, con->xendev.dom,
> con->ring_ref,
> diff --git a/hw/display/xenfb.c b/hw/display/xenfb.c
> index 5e324ef..c96d974 100644
> --- a/hw/display/xenfb.c
> +++ b/hw/display/xenfb.c
> @@ -104,9 +104,8 @@ static int common_bind(struct common *c)
> if (xenstore_read_fe_int(&c->xendev, "event-channel", &c->xendev.remote_port) == -1)
> return -1;
>
> - c->page = xc_map_foreign_range(xen_xc, c->xendev.dom,
> - XC_PAGE_SIZE,
> - PROT_READ | PROT_WRITE, mfn);
> + c->page = xc_map_foreign_pages(xen_xc, c->xendev.dom,
> + PROT_READ | PROT_WRITE, &mfn, 1);
> if (c->page == NULL)
> return -1;
>
> diff --git a/xen-hvm.c b/xen-hvm.c
> index 6680782..2f4e109 100644
> --- a/xen-hvm.c
> +++ b/xen-hvm.c
> @@ -1240,8 +1240,9 @@ int xen_hvm_init(PCMachineState *pcms,
> DPRINTF("buffered io page at pfn %lx\n", bufioreq_pfn);
> DPRINTF("buffered io evtchn is %x\n", bufioreq_evtchn);
>
> - state->shared_page = xc_map_foreign_range(xen_xc, xen_domid, XC_PAGE_SIZE,
> - PROT_READ|PROT_WRITE, ioreq_pfn);
> + state->shared_page = xc_map_foreign_pages(xen_xc, xen_domid,
> + PROT_READ|PROT_WRITE,
> + &ioreq_pfn, 1);
> if (state->shared_page == NULL) {
> hw_error("map shared IO page returned error %d handle=" XC_INTERFACE_FMT,
> errno, xen_xc);
> @@ -1251,8 +1252,8 @@ int xen_hvm_init(PCMachineState *pcms,
> if (!rc) {
> DPRINTF("shared vmport page at pfn %lx\n", ioreq_pfn);
> state->shared_vmport_page =
> - xc_map_foreign_range(xen_xc, xen_domid, XC_PAGE_SIZE,
> - PROT_READ|PROT_WRITE, ioreq_pfn);
> + xc_map_foreign_pages(xen_xc, xen_domid, PROT_READ|PROT_WRITE,
> + &ioreq_pfn, 1);
> if (state->shared_vmport_page == NULL) {
> hw_error("map shared vmport IO page returned error %d handle="
> XC_INTERFACE_FMT, errno, xen_xc);
> @@ -1261,10 +1262,9 @@ int xen_hvm_init(PCMachineState *pcms,
> hw_error("get vmport regs pfn returned error %d, rc=%d", errno, rc);
> }
>
> - state->buffered_io_page = xc_map_foreign_range(xen_xc, xen_domid,
> - XC_PAGE_SIZE,
> + state->buffered_io_page = xc_map_foreign_pages(xen_xc, xen_domid,
> PROT_READ|PROT_WRITE,
> - bufioreq_pfn);
> + &bufioreq_pfn, 1);
> if (state->buffered_io_page == NULL) {
> hw_error("map buffered IO page returned error %d", errno);
> }
> --
> 2.1.4
>
^ permalink raw reply [flat|nested] 20+ messages in thread
* Re: [Qemu-devel] [PATCH QEMU-XEN v6 6/8] xen: Use stable library interfaces when they are available.
2015-12-03 11:23 ` [Qemu-devel] [PATCH QEMU-XEN v6 6/8] xen: Use stable library interfaces when they are available Ian Campbell
@ 2015-12-04 15:31 ` Stefano Stabellini
0 siblings, 0 replies; 20+ messages in thread
From: Stefano Stabellini @ 2015-12-04 15:31 UTC (permalink / raw)
To: Ian Campbell
Cc: wei.liu2, stefano.stabellini, ian.jackson, qemu-devel, xen-devel
On Thu, 3 Dec 2015, Ian Campbell wrote:
> In Xen 4.7 we are refactoring parts libxenctrl into a number of
> separate libraries which will provide backward and forward API and ABI
> compatiblity.
>
> Specifically libxenevtchn, libxengnttab and libxenforeignmemory.
>
> Previous patches have already laid the groundwork for using these by
> switching the existing compatibility shims to reflect the intefaces to
> these libraries.
>
> So all which remains is to update configure to detect the libraries
> and enable their use. Although they are notionally independent we take
> an all or nothing approach to the three libraries since they were
> added at the same time.
>
> The only non-obvious bit is that we now open a proper xenforeignmemory
> handle for xen_fmem instead of reusing the xen_xc handle.
>
> Build tested with 4.0 .. 4.6 (inclusive) and the patches targetting
> 4.7 which adds these libraries.
>
> Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Reviewed-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
> v6: Two minor formatting things.
> Rebase onto "xen: fix usage of xc_domain_create in domain
> builder", required adjusting the configure script changes.
>
> The rebase wasn't entirely trivial (semantically), so dropped
> Stefano's reviwed by.
>
> v5: Remove ifdef check when undeffing the compat stuff.
> s/now way/no way/
>
> v4: xenforeignmemory_open is now a compat wrapper, so no ifdef.
>
> Simplify configury by asserting that interface version 470 will
> always have the libraries (lack of them makes it 460).
>
> Ran checkpatch and fixed everything except:
>
> ERROR: need consistent spacing around '*' (ctx:WxV)
> +typedef xc_interface *XenXC;
>
> Which I think is a false +ve.
>
> Simpler configure stuff
> ---
> configure | 42 +++++++++++++++++++++++++++++++++++++++++-
> include/hw/xen/xen_common.h | 35 +++++++++++++++++++++++++++++++++--
> 2 files changed, 74 insertions(+), 3 deletions(-)
>
> diff --git a/configure b/configure
> index 979bc55..cb72115 100755
> --- a/configure
> +++ b/configure
> @@ -1923,6 +1923,7 @@ fi
>
> if test "$xen" != "no" ; then
> xen_libs="-lxenstore -lxenctrl -lxenguest"
> + xen_stable_libs="-lxenforeignmemory -lxengnttab -lxenevtchn"
>
> # First we test whether Xen headers and libraries are available.
> # If no, we are done and there is no Xen support.
> @@ -1945,16 +1946,52 @@ EOF
> # Xen unstable
> elif
> cat > $TMPC <<EOF &&
> +/*
> + * If we have stable libs the we don't want the libxc compat
> + * layers, regardless of what CFLAGS we may have been given.
> + */
> +#undef XC_WANT_COMPAT_EVTCHN_API
> +#undef XC_WANT_COMPAT_GNTTAB_API
> +#undef XC_WANT_COMPAT_MAP_FOREIGN_API
> #include <xenctrl.h>
> +#include <xenstore.h>
> +#include <xenevtchn.h>
> +#include <xengnttab.h>
> +#include <xenforeignmemory.h>
> #include <stdint.h>
> +#include <xen/hvm/hvm_info_table.h>
> +#if !defined(HVM_MAX_VCPUS)
> +# error HVM_MAX_VCPUS not defined
> +#endif
> int main(void) {
> xc_interface *xc = NULL;
> + xenforeignmemory_handle *xfmem;
> + xenevtchn_handle *xe;
> + xengnttab_handle *xg;
> xen_domain_handle_t handle;
> +
> + xs_daemon_open();
> +
> + xc = xc_interface_open(0, 0, 0);
> + xc_hvm_set_mem_type(0, 0, HVMMEM_ram_ro, 0, 0);
> + xc_domain_add_to_physmap(0, 0, XENMAPSPACE_gmfn, 0, 0);
> + xc_hvm_inject_msi(xc, 0, 0xf0000000, 0x00000000);
> + xc_hvm_create_ioreq_server(xc, 0, HVM_IOREQSRV_BUFIOREQ_ATOMIC, NULL);
> xc_domain_create(xc, 0, handle, 0, NULL, NULL);
> +
> + xfmem = xenforeignmemory_open(0, 0);
> + xenforeignmemory_map(xfmem, 0, 0, 0, 0, 0);
> +
> + xe = xenevtchn_open(0, 0);
> + xenevtchn_fd(xe);
> +
> + xg = xengnttab_open(0, 0);
> + xengnttab_map_grant_ref(xg, 0, 0, 0);
> +
> return 0;
> }
> EOF
> - compile_prog "" "$xen_libs"
> + compile_prog "" "$xen_libs $xen_stable_libs"
> then
> xen_ctrl_version=470
> xen=yes
> @@ -2138,6 +2175,9 @@ EOF
> fi
>
> if test "$xen" = yes; then
> + if test $xen_ctrl_version -ge 470 ; then
> + libs_softmmu="$xen_stable_libs $libs_softmmu"
> + fi
> libs_softmmu="$xen_libs $libs_softmmu"
> fi
> fi
> diff --git a/include/hw/xen/xen_common.h b/include/hw/xen/xen_common.h
> index 8fbaf07..884fbd1 100644
> --- a/include/hw/xen/xen_common.h
> +++ b/include/hw/xen/xen_common.h
> @@ -6,6 +6,15 @@
> #include <stddef.h>
> #include <inttypes.h>
>
> +/*
> + * If we have new enough libxenctrl then we do not want/need these compat
> + * interfaces, despite what the user supplied cflags might say. They
> + * must be undefined before including xenctrl.h
> + */
> +#undef XC_WANT_COMPAT_EVTCHN_API
> +#undef XC_WANT_COMPAT_GNTTAB_API
> +#undef XC_WANT_COMPAT_MAP_FOREIGN_API
> +
> #include <xenctrl.h>
> #if CONFIG_XEN_CTRL_INTERFACE_VERSION < 420
> # include <xs.h>
> @@ -159,8 +168,8 @@ static inline void xs_close(struct xs_handle *xsh)
> }
>
>
> -/* Xen 4.1 */
> -#else
> +/* Xen 4.1 thru 4.6 */
> +#elif CONFIG_XEN_CTRL_INTERFACE_VERSION < 470
>
> typedef xc_interface *XenXC;
> typedef xc_interface *xenforeignmemory_handle;
> @@ -207,6 +216,28 @@ static inline void *xenforeignmemory_map(XenXC *h, uint32_t dom,
>
> #define xenforeignmemory_unmap(h, p, s) munmap(p, s * XC_PAGE_SIZE)
>
> +/* FIXME There is no way to have the xen fd */
> +static inline int xc_fd(xc_interface *xen_xc)
> +{
> + return -1;
> +}
> +#else /* CONFIG_XEN_CTRL_INTERFACE_VERSION >= 470 */
> +
> +typedef xc_interface *XenXC;
> +
> +# define XC_INTERFACE_FMT "%p"
> +# define XC_HANDLER_INITIAL_VALUE NULL
> +
> +#include <xenevtchn.h>
> +#include <xengnttab.h>
> +#include <xenforeignmemory.h>
> +
> +static inline XenXC xen_xc_interface_open(void *logger, void *dombuild_logger,
> + unsigned int open_flags)
> +{
> + return xc_interface_open(logger, dombuild_logger, open_flags);
> +}
> +
> /* FIXME There is now way to have the xen fd */
> static inline int xc_fd(xc_interface *xen_xc)
> {
> --
> 2.1.4
>
^ permalink raw reply [flat|nested] 20+ messages in thread
* Re: [Qemu-devel] [Minios-devel] [PATCH v6 0/<VARIOUS>] Begin to disentangle libxenctrl and provide some stable libraries
2015-12-03 11:21 [Qemu-devel] [Minios-devel] [PATCH v6 0/<VARIOUS>] Begin to disentangle libxenctrl and provide some stable libraries Ian Campbell
2015-12-03 11:23 ` [Qemu-devel] [PATCH QEMU-XEN v6 0/8] " Ian Campbell
@ 2015-12-09 12:37 ` Ian Campbell
1 sibling, 0 replies; 20+ messages in thread
From: Ian Campbell @ 2015-12-09 12:37 UTC (permalink / raw)
To: xen-devel
Cc: Wei Liu, Stefano Stabellini, Ian Jackson, qemu-devel,
minios-devel, samuel.thibault, Roger Pau Monne
On Thu, 2015-12-03 at 11:21 +0000, Ian Campbell wrote:
>
> Last time proposed that these precursors (and the corresponding qemu-xen-
> traditional + mini-os patches) should go in now:
>
> tools/Rules.mk: Properly handle libraries with recursive dependencies.
> tools: Refactor "xentoollog" into its own library
>
> But I subsequently found a couple of build issues, which are addressed by
> two new patches at the head of the xen series.
Which have now been acked, thanks.
I have therefore applied:
To xen.git:
mce-test: do not include libxenguest internal headers
tools/ocaml: simplify compile/link of test apps
tools/Rules.mk: Properly handle libraries with recursive dependencies.
tools: Refactor "xentoollog" into its own library
To qemu-xen-traditional.git:
qemu-xen-traditional: Use xentoollog as a separate library
To mini-os.git:
mini-os: Include libxentoollog with libxc
and I have folded in updates to QEMU_TRADITIONAL_REVISION and
MINIOS_UPSTREAM_REVISION into the xen.git commit "tools: Refactor
"xentoollog" into its own library".
Ian.
^ permalink raw reply [flat|nested] 20+ messages in thread
* Re: [Qemu-devel] [PATCH QEMU-XEN v6 4/8] xen: Switch uses of xc_map_foreign_range into xc_map_foreign_pages
2015-12-03 11:23 ` [Qemu-devel] [PATCH QEMU-XEN v6 4/8] xen: Switch uses of xc_map_foreign_range into xc_map_foreign_pages Ian Campbell
2015-12-04 15:26 ` Stefano Stabellini
@ 2015-12-09 13:41 ` Ian Campbell
2015-12-09 13:56 ` [Qemu-devel] [Xen-devel] " Andrew Cooper
2015-12-11 14:26 ` [Qemu-devel] " Stefano Stabellini
1 sibling, 2 replies; 20+ messages in thread
From: Ian Campbell @ 2015-12-09 13:41 UTC (permalink / raw)
To: stefano.stabellini; +Cc: wei.liu2, ian.jackson, qemu-devel, xen-devel
On Thu, 2015-12-03 at 11:23 +0000, Ian Campbell wrote:
> diff --git a/hw/display/xenfb.c b/hw/display/xenfb.c
> index 5e324ef..c96d974 100644
> --- a/hw/display/xenfb.c
> +++ b/hw/display/xenfb.c
> @@ -104,9 +104,8 @@ static int common_bind(struct common *c)
> if (xenstore_read_fe_int(&c->xendev, "event-channel", &c->xendev.remote_port) == -1)
> return -1;
>
> - c->page = xc_map_foreign_range(xen_xc, c->xendev.dom,
> - XC_PAGE_SIZE,
> - PROT_READ | PROT_WRITE, mfn);
> + c->page = xc_map_foreign_pages(xen_xc, c->xendev.dom,
> + PROT_READ | PROT_WRITE, &mfn, 1);
This doesn't build for i386 userspace, since mfn is a uint64_t but
xc_map_foreign_pages() wants a xen_pfn_t * (where xen_pfn_t == unsigned
long on x86).
Until now that was just a truncation which was already checked for with:
uint64_t mfn;
if (xenstore_read_fe_uint64(&c->xendev, "page-ref", &mfn) == -1)
return -1;
assert(mfn == (xen_pfn_t)mfn);
I think in principal passing "(xen_pfn_t *)&mfn" would ok (since it is a
singleton array in this case), but I was thinking of going a bit further
and:
diff --git a/hw/display/xenfb.c b/hw/display/xenfb.c
index 8b86b4a..54585fa 100644
--- a/hw/display/xenfb.c
+++ b/hw/display/xenfb.c
@@ -95,11 +95,13 @@ struct XenFB {
static int common_bind(struct common *c)
{
- uint64_t mfn;
+ uint64_t val;
+ xen_pfn_t mfn;
- if (xenstore_read_fe_uint64(&c->xendev, "page-ref", &mfn) == -1)
+ if (xenstore_read_fe_uint64(&c->xendev, "page-ref", &val) == -1)
return -1;
- assert(mfn == (xen_pfn_t)mfn);
+ mfn = (xen_pfn_t)val;
+ assert(val == mfn);
if (xenstore_read_fe_int(&c->xendev, "event-channel", &c->xendev.remote_port) == -1)
return -1;
Stefano, what do you think/prefer? An alternative to the above
I've not spotted any other similar constructs, xenfb is a bit unusual here
in that it apparently uses foreign mappings rather than grants like most
drivers do.
Ian.
^ permalink raw reply related [flat|nested] 20+ messages in thread
* Re: [Qemu-devel] [Xen-devel] [PATCH QEMU-XEN v6 4/8] xen: Switch uses of xc_map_foreign_range into xc_map_foreign_pages
2015-12-09 13:41 ` Ian Campbell
@ 2015-12-09 13:56 ` Andrew Cooper
2015-12-09 14:05 ` Ian Campbell
2015-12-11 14:26 ` [Qemu-devel] " Stefano Stabellini
1 sibling, 1 reply; 20+ messages in thread
From: Andrew Cooper @ 2015-12-09 13:56 UTC (permalink / raw)
To: Ian Campbell, stefano.stabellini
Cc: ian.jackson, wei.liu2, qemu-devel, xen-devel
On 09/12/15 13:41, Ian Campbell wrote:
> On Thu, 2015-12-03 at 11:23 +0000, Ian Campbell wrote:
>> diff --git a/hw/display/xenfb.c b/hw/display/xenfb.c
>> index 5e324ef..c96d974 100644
>> --- a/hw/display/xenfb.c
>> +++ b/hw/display/xenfb.c
>> @@ -104,9 +104,8 @@ static int common_bind(struct common *c)
>> if (xenstore_read_fe_int(&c->xendev, "event-channel", &c->xendev.remote_port) == -1)
>> return -1;
>>
>> - c->page = xc_map_foreign_range(xen_xc, c->xendev.dom,
>> - XC_PAGE_SIZE,
>> - PROT_READ | PROT_WRITE, mfn);
>> + c->page = xc_map_foreign_pages(xen_xc, c->xendev.dom,
>> + PROT_READ | PROT_WRITE, &mfn, 1);
> This doesn't build for i386 userspace, since mfn is a uint64_t but
> xc_map_foreign_pages() wants a xen_pfn_t * (where xen_pfn_t == unsigned
> long on x86).
>
> Until now that was just a truncation which was already checked for with:
>
> uint64_t mfn;
>
> if (xenstore_read_fe_uint64(&c->xendev, "page-ref", &mfn) == -1)
> return -1;
> assert(mfn == (xen_pfn_t)mfn);
>
> I think in principal passing "(xen_pfn_t *)&mfn" would ok (since it is a
> singleton array in this case), but I was thinking of going a bit further
> and:
It is never ok to convert a pointer like this. In 32bit (little endian)
userspace, it will leave the upper half of mfn uninitialised on the stack.
~Andrew
^ permalink raw reply [flat|nested] 20+ messages in thread
* Re: [Qemu-devel] [Xen-devel] [PATCH QEMU-XEN v6 4/8] xen: Switch uses of xc_map_foreign_range into xc_map_foreign_pages
2015-12-09 13:56 ` [Qemu-devel] [Xen-devel] " Andrew Cooper
@ 2015-12-09 14:05 ` Ian Campbell
0 siblings, 0 replies; 20+ messages in thread
From: Ian Campbell @ 2015-12-09 14:05 UTC (permalink / raw)
To: Andrew Cooper, stefano.stabellini
Cc: ian.jackson, wei.liu2, qemu-devel, xen-devel
On Wed, 2015-12-09 at 13:56 +0000, Andrew Cooper wrote:
> On 09/12/15 13:41, Ian Campbell wrote:
> > On Thu, 2015-12-03 at 11:23 +0000, Ian Campbell wrote:
> > > diff --git a/hw/display/xenfb.c b/hw/display/xenfb.c
> > > index 5e324ef..c96d974 100644
> > > --- a/hw/display/xenfb.c
> > > +++ b/hw/display/xenfb.c
> > > @@ -104,9 +104,8 @@ static int common_bind(struct common *c)
> > > if (xenstore_read_fe_int(&c->xendev, "event-channel", &c-
> > > >xendev.remote_port) == -1)
> > > return -1;
> > >
> > > - c->page = xc_map_foreign_range(xen_xc, c->xendev.dom,
> > > - XC_PAGE_SIZE,
> > > - PROT_READ | PROT_WRITE, mfn);
> > > + c->page = xc_map_foreign_pages(xen_xc, c->xendev.dom,
> > > + PROT_READ | PROT_WRITE, &mfn, 1);
> > This doesn't build for i386 userspace, since mfn is a uint64_t but
> > xc_map_foreign_pages() wants a xen_pfn_t * (where xen_pfn_t == unsigned
> > long on x86).
> >
> > Until now that was just a truncation which was already checked for
> > with:
> >
> > uint64_t mfn;
> >
> > if (xenstore_read_fe_uint64(&c->xendev, "page-ref", &mfn) == -1)
> > return -1;
> > assert(mfn == (xen_pfn_t)mfn);
> >
> > I think in principal passing "(xen_pfn_t *)&mfn" would ok (since it is
> > a
> > singleton array in this case), but I was thinking of going a bit
> > further
> > and:
>
> It is never ok to convert a pointer like this. In 32bit (little endian)
> userspace, it will leave the upper half of mfn uninitialised on the
> stack.
mfn is a 32-bit value on such systems, so there is no upper half any way.
NB I was talking about passing to xc_map_..., not the call to
xenstore_read_fe...
In any case my preference is the more long winded way I had further down.
Ian.
^ permalink raw reply [flat|nested] 20+ messages in thread
* Re: [Qemu-devel] [PATCH QEMU-XEN v6 4/8] xen: Switch uses of xc_map_foreign_range into xc_map_foreign_pages
2015-12-09 13:41 ` Ian Campbell
2015-12-09 13:56 ` [Qemu-devel] [Xen-devel] " Andrew Cooper
@ 2015-12-11 14:26 ` Stefano Stabellini
2015-12-11 15:23 ` Ian Campbell
1 sibling, 1 reply; 20+ messages in thread
From: Stefano Stabellini @ 2015-12-11 14:26 UTC (permalink / raw)
To: Ian Campbell
Cc: wei.liu2, xen-devel, ian.jackson, qemu-devel, stefano.stabellini
[-- Attachment #1: Type: text/plain, Size: 2161 bytes --]
On Wed, 9 Dec 2015, Ian Campbell wrote:
> On Thu, 2015-12-03 at 11:23 +0000, Ian Campbell wrote:
> > diff --git a/hw/display/xenfb.c b/hw/display/xenfb.c
> > index 5e324ef..c96d974 100644
> > --- a/hw/display/xenfb.c
> > +++ b/hw/display/xenfb.c
> > @@ -104,9 +104,8 @@ static int common_bind(struct common *c)
> > if (xenstore_read_fe_int(&c->xendev, "event-channel", &c->xendev.remote_port) == -1)
> > return -1;
> >
> > - c->page = xc_map_foreign_range(xen_xc, c->xendev.dom,
> > - XC_PAGE_SIZE,
> > - PROT_READ | PROT_WRITE, mfn);
> > + c->page = xc_map_foreign_pages(xen_xc, c->xendev.dom,
> > + PROT_READ | PROT_WRITE, &mfn, 1);
>
> This doesn't build for i386 userspace, since mfn is a uint64_t but
> xc_map_foreign_pages() wants a xen_pfn_t * (where xen_pfn_t == unsigned
> long on x86).
>
> Until now that was just a truncation which was already checked for with:
>
> uint64_t mfn;
>
> if (xenstore_read_fe_uint64(&c->xendev, "page-ref", &mfn) == -1)
> return -1;
> assert(mfn == (xen_pfn_t)mfn);
>
> I think in principal passing "(xen_pfn_t *)&mfn" would ok (since it is a
> singleton array in this case), but I was thinking of going a bit further
> and:
>
> diff --git a/hw/display/xenfb.c b/hw/display/xenfb.c
> index 8b86b4a..54585fa 100644
> --- a/hw/display/xenfb.c
> +++ b/hw/display/xenfb.c
> @@ -95,11 +95,13 @@ struct XenFB {
>
> static int common_bind(struct common *c)
> {
> - uint64_t mfn;
> + uint64_t val;
> + xen_pfn_t mfn;
>
> - if (xenstore_read_fe_uint64(&c->xendev, "page-ref", &mfn) == -1)
> + if (xenstore_read_fe_uint64(&c->xendev, "page-ref", &val) == -1)
> return -1;
> - assert(mfn == (xen_pfn_t)mfn);
> + mfn = (xen_pfn_t)val;
> + assert(val == mfn);
>
> if (xenstore_read_fe_int(&c->xendev, "event-channel", &c->xendev.remote_port) == -1)
> return -1;
>
> Stefano, what do you think/prefer? An alternative to the above
I like this change because it makes the code more obvious
^ permalink raw reply [flat|nested] 20+ messages in thread
* Re: [Qemu-devel] [PATCH QEMU-XEN v6 4/8] xen: Switch uses of xc_map_foreign_range into xc_map_foreign_pages
2015-12-11 14:26 ` [Qemu-devel] " Stefano Stabellini
@ 2015-12-11 15:23 ` Ian Campbell
2015-12-11 16:42 ` Stefano Stabellini
0 siblings, 1 reply; 20+ messages in thread
From: Ian Campbell @ 2015-12-11 15:23 UTC (permalink / raw)
To: Stefano Stabellini; +Cc: wei.liu2, ian.jackson, qemu-devel, xen-devel
On Fri, 2015-12-11 at 14:26 +0000, Stefano Stabellini wrote:
> On Wed, 9 Dec 2015, Ian Campbell wrote:
> > On Thu, 2015-12-03 at 11:23 +0000, Ian Campbell wrote:
> > > diff --git a/hw/display/xenfb.c b/hw/display/xenfb.c
> > > index 5e324ef..c96d974 100644
> > > --- a/hw/display/xenfb.c
> > > +++ b/hw/display/xenfb.c
> > > @@ -104,9 +104,8 @@ static int common_bind(struct common *c)
> > > if (xenstore_read_fe_int(&c->xendev, "event-channel", &c-
> > > >xendev.remote_port) == -1)
> > > return -1;
> > >
> > > - c->page = xc_map_foreign_range(xen_xc, c->xendev.dom,
> > > - XC_PAGE_SIZE,
> > > - PROT_READ | PROT_WRITE, mfn);
> > > + c->page = xc_map_foreign_pages(xen_xc, c->xendev.dom,
> > > + PROT_READ | PROT_WRITE, &mfn, 1);
> >
> > This doesn't build for i386 userspace, since mfn is a uint64_t but
> > xc_map_foreign_pages() wants a xen_pfn_t * (where xen_pfn_t == unsigned
> > long on x86).
> >
> > Until now that was just a truncation which was already checked for
> > with:
> >
> > uint64_t mfn;
> >
> > if (xenstore_read_fe_uint64(&c->xendev, "page-ref", &mfn) == -1)
> > return -1;
> > assert(mfn == (xen_pfn_t)mfn);
> >
> > I think in principal passing "(xen_pfn_t *)&mfn" would ok (since it is
> > a
> > singleton array in this case), but I was thinking of going a bit
> > further
> > and:
> >
> > diff --git a/hw/display/xenfb.c b/hw/display/xenfb.c
> > index 8b86b4a..54585fa 100644
> > --- a/hw/display/xenfb.c
> > +++ b/hw/display/xenfb.c
> > @@ -95,11 +95,13 @@ struct XenFB {
> >
> > static int common_bind(struct common *c)
> > {
> > - uint64_t mfn;
> > + uint64_t val;
> > + xen_pfn_t mfn;
> >
> > - if (xenstore_read_fe_uint64(&c->xendev, "page-ref", &mfn) == -1)
> > + if (xenstore_read_fe_uint64(&c->xendev, "page-ref", &val) == -1)
> > return -1;
> > - assert(mfn == (xen_pfn_t)mfn);
> > + mfn = (xen_pfn_t)val;
> > + assert(val == mfn);
> >
> > if (xenstore_read_fe_int(&c->xendev, "event-channel", &c-
> > >xendev.remote_port) == -1)
> > return -1;
> >
> > Stefano, what do you think/prefer? An alternative to the above
>
> I like this change because it makes the code more obvious
Thanks, with that change may I keep your Reviewed-by?
^ permalink raw reply [flat|nested] 20+ messages in thread
* Re: [Qemu-devel] [PATCH QEMU-XEN v6 4/8] xen: Switch uses of xc_map_foreign_range into xc_map_foreign_pages
2015-12-11 15:23 ` Ian Campbell
@ 2015-12-11 16:42 ` Stefano Stabellini
0 siblings, 0 replies; 20+ messages in thread
From: Stefano Stabellini @ 2015-12-11 16:42 UTC (permalink / raw)
To: Ian Campbell
Cc: wei.liu2, xen-devel, ian.jackson, qemu-devel, Stefano Stabellini
[-- Attachment #1: Type: text/plain, Size: 2593 bytes --]
On Fri, 11 Dec 2015, Ian Campbell wrote:
> On Fri, 2015-12-11 at 14:26 +0000, Stefano Stabellini wrote:
> > On Wed, 9 Dec 2015, Ian Campbell wrote:
> > > On Thu, 2015-12-03 at 11:23 +0000, Ian Campbell wrote:
> > > > diff --git a/hw/display/xenfb.c b/hw/display/xenfb.c
> > > > index 5e324ef..c96d974 100644
> > > > --- a/hw/display/xenfb.c
> > > > +++ b/hw/display/xenfb.c
> > > > @@ -104,9 +104,8 @@ static int common_bind(struct common *c)
> > > > if (xenstore_read_fe_int(&c->xendev, "event-channel", &c-
> > > > >xendev.remote_port) == -1)
> > > > return -1;
> > > >
> > > > - c->page = xc_map_foreign_range(xen_xc, c->xendev.dom,
> > > > - XC_PAGE_SIZE,
> > > > - PROT_READ | PROT_WRITE, mfn);
> > > > + c->page = xc_map_foreign_pages(xen_xc, c->xendev.dom,
> > > > + PROT_READ | PROT_WRITE, &mfn, 1);
> > >
> > > This doesn't build for i386 userspace, since mfn is a uint64_t but
> > > xc_map_foreign_pages() wants a xen_pfn_t * (where xen_pfn_t == unsigned
> > > long on x86).
> > >
> > > Until now that was just a truncation which was already checked for
> > > with:
> > >
> > > uint64_t mfn;
> > >
> > > if (xenstore_read_fe_uint64(&c->xendev, "page-ref", &mfn) == -1)
> > > return -1;
> > > assert(mfn == (xen_pfn_t)mfn);
> > >
> > > I think in principal passing "(xen_pfn_t *)&mfn" would ok (since it is
> > > a
> > > singleton array in this case), but I was thinking of going a bit
> > > further
> > > and:
> > >
> > > diff --git a/hw/display/xenfb.c b/hw/display/xenfb.c
> > > index 8b86b4a..54585fa 100644
> > > --- a/hw/display/xenfb.c
> > > +++ b/hw/display/xenfb.c
> > > @@ -95,11 +95,13 @@ struct XenFB {
> > >
> > > static int common_bind(struct common *c)
> > > {
> > > - uint64_t mfn;
> > > + uint64_t val;
> > > + xen_pfn_t mfn;
> > >
> > > - if (xenstore_read_fe_uint64(&c->xendev, "page-ref", &mfn) == -1)
> > > + if (xenstore_read_fe_uint64(&c->xendev, "page-ref", &val) == -1)
> > > return -1;
> > > - assert(mfn == (xen_pfn_t)mfn);
> > > + mfn = (xen_pfn_t)val;
> > > + assert(val == mfn);
> > >
> > > if (xenstore_read_fe_int(&c->xendev, "event-channel", &c-
> > > >xendev.remote_port) == -1)
> > > return -1;
> > >
> > > Stefano, what do you think/prefer? An alternative to the above
> >
> > I like this change because it makes the code more obvious
>
> Thanks, with that change may I keep your Reviewed-by?
Sure
^ permalink raw reply [flat|nested] 20+ messages in thread
end of thread, other threads:[~2015-12-11 16:43 UTC | newest]
Thread overview: 20+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2015-12-03 11:21 [Qemu-devel] [Minios-devel] [PATCH v6 0/<VARIOUS>] Begin to disentangle libxenctrl and provide some stable libraries Ian Campbell
2015-12-03 11:23 ` [Qemu-devel] [PATCH QEMU-XEN v6 0/8] " Ian Campbell
2015-12-03 11:23 ` [Qemu-devel] [PATCH QEMU-XEN v6 1/8] xen_console: correctly cleanup primary console on teardown Ian Campbell
2015-12-03 11:23 ` [Qemu-devel] [PATCH QEMU-XEN v6 2/8] xen: Switch to libxenevtchn interface for compat shims Ian Campbell
2015-12-03 11:23 ` [Qemu-devel] [PATCH QEMU-XEN v6 3/8] xen: Switch to libxengnttab " Ian Campbell
2015-12-03 11:23 ` [Qemu-devel] [PATCH QEMU-XEN v6 4/8] xen: Switch uses of xc_map_foreign_range into xc_map_foreign_pages Ian Campbell
2015-12-04 15:26 ` Stefano Stabellini
2015-12-09 13:41 ` Ian Campbell
2015-12-09 13:56 ` [Qemu-devel] [Xen-devel] " Andrew Cooper
2015-12-09 14:05 ` Ian Campbell
2015-12-11 14:26 ` [Qemu-devel] " Stefano Stabellini
2015-12-11 15:23 ` Ian Campbell
2015-12-11 16:42 ` Stefano Stabellini
2015-12-03 11:23 ` [Qemu-devel] [PATCH QEMU-XEN v6 5/8] xen: Switch uses of xc_map_foreign_{pages, bulk} to use libxenforeignmemory API Ian Campbell
2015-12-04 15:26 ` Stefano Stabellini
2015-12-03 11:23 ` [Qemu-devel] [PATCH QEMU-XEN v6 6/8] xen: Use stable library interfaces when they are available Ian Campbell
2015-12-04 15:31 ` Stefano Stabellini
2015-12-03 11:23 ` [Qemu-devel] [PATCH QEMU-XEN v6 7/8] xen: domainbuild: reopen libxenctrl interface after forking for domain watcher Ian Campbell
2015-12-03 11:23 ` [Qemu-devel] [PATCH QEMU-XEN v6 8/8] xen: make it possible to build without the Xen PV domain builder Ian Campbell
2015-12-09 12:37 ` [Qemu-devel] [Minios-devel] [PATCH v6 0/<VARIOUS>] Begin to disentangle libxenctrl and provide some stable libraries Ian Campbell
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