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-rw-r--r--hw/block/xen-block.c14
-rw-r--r--hw/i386/xen/xen-hvm.c9
-rw-r--r--hw/i386/xen/xen-mapcache.c15
-rw-r--r--include/hw/xen/xen_common.h6
4 files changed, 39 insertions, 5 deletions
diff --git a/hw/block/xen-block.c b/hw/block/xen-block.c
index 83754a4344..674953f1ad 100644
--- a/hw/block/xen-block.c
+++ b/hw/block/xen-block.c
@@ -728,6 +728,8 @@ static XenBlockDrive *xen_block_drive_create(const char *id,
XenBlockDrive *drive = NULL;
QDict *file_layer;
QDict *driver_layer;
+ struct stat st;
+ int rc;
if (params) {
char **v = g_strsplit(params, ":", 2);
@@ -761,7 +763,17 @@ static XenBlockDrive *xen_block_drive_create(const char *id,
file_layer = qdict_new();
driver_layer = qdict_new();
- qdict_put_str(file_layer, "driver", "file");
+ rc = stat(filename, &st);
+ if (rc) {
+ error_setg_errno(errp, errno, "Could not stat file '%s'", filename);
+ goto done;
+ }
+ if (S_ISBLK(st.st_mode)) {
+ qdict_put_str(file_layer, "driver", "host_device");
+ } else {
+ qdict_put_str(file_layer, "driver", "file");
+ }
+
qdict_put_str(file_layer, "filename", filename);
g_free(filename);
diff --git a/hw/i386/xen/xen-hvm.c b/hw/i386/xen/xen-hvm.c
index c53fa17c50..9b432773f0 100644
--- a/hw/i386/xen/xen-hvm.c
+++ b/hw/i386/xen/xen-hvm.c
@@ -108,6 +108,7 @@ typedef struct XenIOState {
shared_iopage_t *shared_page;
shared_vmport_iopage_t *shared_vmport_page;
buffered_iopage_t *buffered_io_page;
+ xenforeignmemory_resource_handle *fres;
QEMUTimer *buffered_io_timer;
CPUState **cpu_by_vcpu_id;
/* the evtchn port for polling the notification, */
@@ -1253,6 +1254,9 @@ static void xen_exit_notifier(Notifier *n, void *data)
XenIOState *state = container_of(n, XenIOState, exit);
xen_destroy_ioreq_server(xen_domid, state->ioservid);
+ if (state->fres != NULL) {
+ xenforeignmemory_unmap_resource(xen_fmem, state->fres);
+ }
xenevtchn_close(state->xce_handle);
xs_daemon_close(state->xenstore);
@@ -1320,7 +1324,6 @@ static void xen_wakeup_notifier(Notifier *notifier, void *data)
static int xen_map_ioreq_server(XenIOState *state)
{
void *addr = NULL;
- xenforeignmemory_resource_handle *fres;
xen_pfn_t ioreq_pfn;
xen_pfn_t bufioreq_pfn;
evtchn_port_t bufioreq_evtchn;
@@ -1332,12 +1335,12 @@ static int xen_map_ioreq_server(XenIOState *state)
*/
QEMU_BUILD_BUG_ON(XENMEM_resource_ioreq_server_frame_bufioreq != 0);
QEMU_BUILD_BUG_ON(XENMEM_resource_ioreq_server_frame_ioreq(0) != 1);
- fres = xenforeignmemory_map_resource(xen_fmem, xen_domid,
+ state->fres = xenforeignmemory_map_resource(xen_fmem, xen_domid,
XENMEM_resource_ioreq_server,
state->ioservid, 0, 2,
&addr,
PROT_READ | PROT_WRITE, 0);
- if (fres != NULL) {
+ if (state->fres != NULL) {
trace_xen_map_resource_ioreq(state->ioservid, addr);
state->buffered_io_page = addr;
state->shared_page = addr + TARGET_PAGE_SIZE;
diff --git a/hw/i386/xen/xen-mapcache.c b/hw/i386/xen/xen-mapcache.c
index 5b120ed44b..e82b7dcdd2 100644
--- a/hw/i386/xen/xen-mapcache.c
+++ b/hw/i386/xen/xen-mapcache.c
@@ -171,7 +171,20 @@ static void xen_remap_bucket(MapCacheEntry *entry,
if (!(entry->flags & XEN_MAPCACHE_ENTRY_DUMMY)) {
ram_block_notify_remove(entry->vaddr_base, entry->size);
}
- if (munmap(entry->vaddr_base, entry->size) != 0) {
+
+ /*
+ * If an entry is being replaced by another mapping and we're using
+ * MAP_FIXED flag for it - there is possibility of a race for vaddr
+ * address with another thread doing an mmap call itself
+ * (see man 2 mmap). To avoid that we skip explicit unmapping here
+ * and allow the kernel to destroy the previous mappings by replacing
+ * them in mmap call later.
+ *
+ * Non-identical replacements are not allowed therefore.
+ */
+ assert(!vaddr || (entry->vaddr_base == vaddr && entry->size == size));
+
+ if (!vaddr && munmap(entry->vaddr_base, entry->size) != 0) {
perror("unmap fails");
exit(-1);
}
diff --git a/include/hw/xen/xen_common.h b/include/hw/xen/xen_common.h
index 82e56339dd..a8118b41ac 100644
--- a/include/hw/xen/xen_common.h
+++ b/include/hw/xen/xen_common.h
@@ -134,6 +134,12 @@ static inline xenforeignmemory_resource_handle *xenforeignmemory_map_resource(
return NULL;
}
+static inline int xenforeignmemory_unmap_resource(
+ xenforeignmemory_handle *fmem, xenforeignmemory_resource_handle *fres)
+{
+ return 0;
+}
+
#endif /* CONFIG_XEN_CTRL_INTERFACE_VERSION < 41100 */
#if CONFIG_XEN_CTRL_INTERFACE_VERSION < 41000