This in turn requires storing the gfn into xs_state_connection for
resume purposes, which breaks the current format.
Note this is a preparatory patch in order to support the usage of
xenstore on domains without grant table. This not only allows xenstore
usage, but also makes things like "@introduceDomain" events work when
using such guests, otherwise the mapping done in introduce_domain
fails and the "@introduceDomain" event won't be signaled.
Signed-off-by: Roger Pau Monné <roger.pau@xxxxxxxxxx>
---
tools/xenstore/Makefile | 4 +-
tools/xenstore/include/xenstore_state.h | 1 +
tools/xenstore/xenstored_domain.c | 69 +++++++++++++++++++------
3 files changed, 56 insertions(+), 18 deletions(-)
diff --git a/tools/xenstore/Makefile b/tools/xenstore/Makefile
index 292b478fa1..9a9f7be5cb 100644
--- a/tools/xenstore/Makefile
+++ b/tools/xenstore/Makefile
@@ -67,10 +67,10 @@ $(XENSTORED_OBJS): CFLAGS += $(SYSTEMD_CFLAGS)
xenstored: LDFLAGS += $(SYSTEMD_LIBS)
endif
-$(XENSTORED_OBJS): CFLAGS += $(CFLAGS_libxengnttab)
+$(XENSTORED_OBJS): CFLAGS += $(CFLAGS_libxengnttab)
$(CFLAGS_libxenforeignmemory)
xenstored: $(XENSTORED_OBJS)
- $(CC) $^ $(LDFLAGS) $(LDLIBS_libxenevtchn) $(LDLIBS_libxengnttab)
$(LDLIBS_libxenctrl) $(LDLIBS_xenstored) $(SOCKET_LIBS) -o $@ $(APPEND_LDFLAGS)
+ $(CC) $^ $(LDFLAGS) $(LDLIBS_libxenevtchn) $(LDLIBS_libxengnttab)
$(LDLIBS_libxenforeignmemory) $(LDLIBS_libxenctrl) $(LDLIBS_xenstored)
$(SOCKET_LIBS) -o $@ $(APPEND_LDFLAGS)
xenstored.a: $(XENSTORED_OBJS)
$(AR) cr $@ $^
diff --git a/tools/xenstore/include/xenstore_state.h
b/tools/xenstore/include/xenstore_state.h
index ae0d053c8f..8dcc8d9d8b 100644
--- a/tools/xenstore/include/xenstore_state.h
+++ b/tools/xenstore/include/xenstore_state.h
@@ -80,6 +80,7 @@ struct xs_state_connection {
uint16_t domid; /* Domain-Id. */
uint16_t tdomid; /* Id of target domain or DOMID_INVALID. */
uint32_t evtchn; /* Event channel port. */
+ uint64_t gfn; /* Store GFN. */
} ring;
int32_t socket_fd; /* File descriptor for socket connections. */
} spec;
diff --git a/tools/xenstore/xenstored_domain.c
b/tools/xenstore/xenstored_domain.c
index 8930303773..f3563e47aa 100644
--- a/tools/xenstore/xenstored_domain.c
+++ b/tools/xenstore/xenstored_domain.c
@@ -33,10 +33,12 @@
#include <xenevtchn.h>
#include <xenctrl.h>
+#include <xenforeignmemory.h>
#include <xen/grant_table.h>
static xc_interface *xc_handle;
xengnttab_handle *xgt_handle;
+static xenforeignmemory_handle *xfm_handle;
static evtchn_port_t virq_port;
xenevtchn_handle *xce_handle = NULL;
@@ -66,12 +68,18 @@ struct domain
/* Generation count at domain introduction time. */
uint64_t generation;
+ /* Store GFN (if using a ring connection). */
+ xen_pfn_t gfn;
+
/* Have we noticed that this domain is shutdown? */
bool shutdown;
/* Has domain been officially introduced? */
bool introduced;
+ /* Is the ring memory foreign mapped? */
+ bool foreign_mapped;
+
/* number of entry from this domain in the store */
int nbentry;
@@ -196,16 +204,29 @@ static const struct interface_funcs domain_funcs = {
.can_read = domain_can_read,
};
-static void *map_interface(domid_t domid)
+static void *map_interface(domid_t domid, xen_pfn_t gfn, bool *foreign_mapped)
{
- return xengnttab_map_grant_ref(xgt_handle, domid,
- GNTTAB_RESERVED_XENSTORE,
- PROT_READ|PROT_WRITE);
+ void *map = xengnttab_map_grant_ref(xgt_handle, domid,
+ GNTTAB_RESERVED_XENSTORE,
+ PROT_READ|PROT_WRITE);
+
+ if (!map)
+ {
+ map = xenforeignmemory_map(xfm_handle, domid,
+ PROT_READ|PROT_WRITE, 1,
+ &gfn, NULL);
+ *foreign_mapped = !!map;
+ }
+
+ return map;
}
-static void unmap_interface(void *interface)
+static void unmap_interface(void *interface, bool foreign_mapped)
{
- xengnttab_unmap(xgt_handle, interface, 1);
+ if (foreign_mapped)
+ xenforeignmemory_unmap(xfm_handle, interface, 1);
+ else
+ xengnttab_unmap(xgt_handle, interface, 1);
}
static int destroy_domain(void *_domain)
@@ -228,7 +249,8 @@ static int destroy_domain(void *_domain)
if (domain->domid == 0)
unmap_xenbus(domain->interface);
else
- unmap_interface(domain->interface);
+ unmap_interface(domain->interface,
+ domain->foreign_mapped);
}
fire_watches(NULL, domain, "@releaseDomain", NULL, false, NULL);
@@ -363,12 +385,15 @@ static struct domain *find_or_alloc_domain(const void
*ctx, unsigned int domid)
return domain ? : alloc_domain(ctx, domid);
}
-static int new_domain(struct domain *domain, int port, bool restore)
+static int new_domain(struct domain *domain, int port, xen_pfn_t gfn,
+ bool foreign_mapped, bool restore)
{
int rc;
domain->port = 0;
domain->shutdown = false;
+ domain->gfn = gfn;
+ domain->foreign_mapped = foreign_mapped;
domain->path = talloc_domain_path(domain, domain->domid);
if (!domain->path) {
errno = ENOMEM;
@@ -436,7 +461,8 @@ static void domain_conn_reset(struct domain *domain)
static struct domain *introduce_domain(const void *ctx,
unsigned int domid,
- evtchn_port_t port, bool restore)
+ evtchn_port_t port, xen_pfn_t gfn,
+ bool restore)
{
struct domain *domain;
int rc;
@@ -448,17 +474,21 @@ static struct domain *introduce_domain(const void *ctx,
return NULL;
if (!domain->introduced) {
+ bool foreign_mapped = false;
+
interface = is_master_domain ? xenbus_map()
- : map_interface(domid);
+ : map_interface(domid, gfn,
+ &foreign_mapped);
if (!interface && !restore)
return NULL;
- if (new_domain(domain, port, restore)) {
+ if (new_domain(domain, port, gfn, foreign_mapped, restore)) {
rc = errno;
if (interface) {
if (is_master_domain)
unmap_xenbus(interface);
else
- unmap_interface(interface);
+ unmap_interface(interface,
+ foreign_mapped);
}
errno = rc;
return NULL;
@@ -489,19 +519,20 @@ int do_introduce(struct connection *conn, struct
buffered_data *in)
char *vec[3];
unsigned int domid;
evtchn_port_t port;
+ xen_pfn_t gfn;
if (get_strings(in, vec, ARRAY_SIZE(vec)) < ARRAY_SIZE(vec))
return EINVAL;
domid = atoi(vec[0]);
- /* Ignore the gfn, we don't need it. */
+ gfn = atol(vec[1]);
port = atoi(vec[2]);
/* Sanity check args. */
if (port <= 0)
return EINVAL;
- domain = introduce_domain(in, domid, port, false);
+ domain = introduce_domain(in, domid, port, gfn, false);
if (!domain)
return errno;
@@ -718,7 +749,7 @@ void dom0_init(void)
if (port == -1)
barf_perror("Failed to initialize dom0 port");
- dom0 = introduce_domain(NULL, xenbus_master_domid(), port, false);
+ dom0 = introduce_domain(NULL, xenbus_master_domid(), port, 0, false);
if (!dom0)
barf_perror("Failed to initialize dom0");
@@ -758,6 +789,10 @@ void domain_init(int evtfd)
*/
xengnttab_set_max_grants(xgt_handle, DOMID_FIRST_RESERVED);
+ xfm_handle = xenforeignmemory_open(NULL, 0);
+ if (!xfm_handle)
+ barf_perror("Failed to create handle for foreign memory");
+
if (evtfd < 0)
xce_handle = xenevtchn_open(NULL, XENEVTCHN_NO_CLOEXEC);
else
@@ -1189,6 +1224,7 @@ const char *dump_state_connections(FILE *fp)
sc.spec.ring.tdomid = c->target ? c->target->id
: DOMID_INVALID;
sc.spec.ring.evtchn = c->domain->port;
+ sc.spec.ring.gfn = c->domain->gfn;
} else {
sc.conn_type = XS_STATE_CONN_TYPE_SOCKET;
sc.spec.socket_fd = c->fd;
@@ -1290,7 +1326,8 @@ void read_state_connection(const void *ctx, const void
*state)
#endif
} else {
domain = introduce_domain(ctx, sc->spec.ring.domid,
- sc->spec.ring.evtchn, true);
+ sc->spec.ring.evtchn,
+ sc->spec.ring.gfn, true);
if (!domain)
barf("domain allocation error");
