Merge remote-tracking branch 'remotes/mst/tags/for_upstream' into staging

virtio,acpi: features, fixes, cleanups.

vdpa support
virtio-mem support
a handy script for disassembling acpi tables
misc fixes and cleanups

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

# gpg: Signature made Tue 07 Jul 2020 13:00:35 BST
# gpg:                using RSA key 5D09FD0871C8F85B94CA8A0D281F0DB8D28D5469
# gpg:                issuer "mst@redhat.com"
# gpg: Good signature from "Michael S. Tsirkin <mst@kernel.org>" [full]
# gpg:                 aka "Michael S. Tsirkin <mst@redhat.com>" [full]
# Primary key fingerprint: 0270 606B 6F3C DF3D 0B17  0970 C350 3912 AFBE 8E67
#      Subkey fingerprint: 5D09 FD08 71C8 F85B 94CA  8A0D 281F 0DB8 D28D 5469

* remotes/mst/tags/for_upstream: (41 commits)
  vhost-vdpa: introduce vhost-vdpa net client
  vhost-vdpa: introduce vhost-vdpa backend
  vhost_net: introduce set_config & get_config
  vhost: implement vhost_force_iommu method
  vhost: introduce new VhostOps vhost_force_iommu
  vhost: implement vhost_vq_get_addr method
  vhost: introduce new VhostOps vhost_vq_get_addr
  vhost: implement vhost_dev_start method
  vhost: introduce new VhostOps vhost_dev_start
  vhost: check the existence of vhost_set_iotlb_callback
  virtio-pci: implement queue_enabled method
  virtio-bus: introduce queue_enabled method
  vhost_net: use the function qemu_get_peer
  net: introduce qemu_get_peer
  MAINTAINERS: add VT-d entry
  docs: vhost-user: add Virtio status protocol feature
  tests/acpi: remove stale allowed tables
  numa: Auto-enable NUMA when any memory devices are possible
  virtio-mem: Exclude unplugged memory during migration
  virtio-mem: Add trace events
  ...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

# Conflicts:
#	hw/arm/virt.c
#	hw/virtio/trace-events

1 files changed, 29 insertions, 24 deletions

diff --git a/hw/vfio/common.c b/hw/vfio/common.c
index 0b3593b3c0..33357140b8 100644
--- a/hw/vfio/common.c
+++ b/hw/vfio/common.c
@@ -33,7 +33,6 @@
 #include "qemu/error-report.h"
 #include "qemu/main-loop.h"
 #include "qemu/range.h"
-#include "sysemu/balloon.h"
 #include "sysemu/kvm.h"
 #include "sysemu/reset.h"
 #include "trace.h"
@@ -1215,31 +1214,36 @@ static int vfio_connect_container(VFIOGroup *group, AddressSpace *as,
     space = vfio_get_address_space(as);
 
     /*
-     * VFIO is currently incompatible with memory ballooning insofar as the
+     * VFIO is currently incompatible with discarding of RAM insofar as the
      * madvise to purge (zap) the page from QEMU's address space does not
      * interact with the memory API and therefore leaves stale virtual to
      * physical mappings in the IOMMU if the page was previously pinned.  We
-     * therefore add a balloon inhibit for each group added to a container,
+     * therefore set discarding broken for each group added to a container,
      * whether the container is used individually or shared.  This provides
      * us with options to allow devices within a group to opt-in and allow
-     * ballooning, so long as it is done consistently for a group (for instance
+     * discarding, so long as it is done consistently for a group (for instance
      * if the device is an mdev device where it is known that the host vendor
      * driver will never pin pages outside of the working set of the guest
-     * driver, which would thus not be ballooning candidates).
+     * driver, which would thus not be discarding candidates).
      *
      * The first opportunity to induce pinning occurs here where we attempt to
      * attach the group to existing containers within the AddressSpace.  If any
-     * pages are already zapped from the virtual address space, such as from a
-     * previous ballooning opt-in, new pinning will cause valid mappings to be
+     * pages are already zapped from the virtual address space, such as from
+     * previous discards, new pinning will cause valid mappings to be
      * re-established.  Likewise, when the overall MemoryListener for a new
      * container is registered, a replay of mappings within the AddressSpace
      * will occur, re-establishing any previously zapped pages as well.
      *
-     * NB. Balloon inhibiting does not currently block operation of the
-     * balloon driver or revoke previously pinned pages, it only prevents
-     * calling madvise to modify the virtual mapping of ballooned pages.
+     * Especially virtio-balloon is currently only prevented from discarding
+     * new memory, it will not yet set ram_block_discard_set_required() and
+     * therefore, neither stops us here or deals with the sudden memory
+     * consumption of inflated memory.
      */
-    qemu_balloon_inhibit(true);
+    ret = ram_block_discard_disable(true);
+    if (ret) {
+        error_setg_errno(errp, -ret, "Cannot set discarding of RAM broken");
+        return ret;
+    }
 
     QLIST_FOREACH(container, &space->containers, next) {
         if (!ioctl(group->fd, VFIO_GROUP_SET_CONTAINER, &container->fd)) {
@@ -1405,7 +1409,7 @@ close_fd_exit:
     close(fd);
 
 put_space_exit:
-    qemu_balloon_inhibit(false);
+    ram_block_discard_disable(false);
     vfio_put_address_space(space);
 
     return ret;
@@ -1526,8 +1530,8 @@ void vfio_put_group(VFIOGroup *group)
         return;
     }
 
-    if (!group->balloon_allowed) {
-        qemu_balloon_inhibit(false);
+    if (!group->ram_block_discard_allowed) {
+        ram_block_discard_disable(false);
     }
     vfio_kvm_device_del_group(group);
     vfio_disconnect_container(group);
@@ -1565,22 +1569,23 @@ int vfio_get_device(VFIOGroup *group, const char *name,
     }
 
     /*
-     * Clear the balloon inhibitor for this group if the driver knows the
-     * device operates compatibly with ballooning.  Setting must be consistent
-     * per group, but since compatibility is really only possible with mdev
-     * currently, we expect singleton groups.
+     * Set discarding of RAM as not broken for this group if the driver knows
+     * the device operates compatibly with discarding.  Setting must be
+     * consistent per group, but since compatibility is really only possible
+     * with mdev currently, we expect singleton groups.
      */
-    if (vbasedev->balloon_allowed != group->balloon_allowed) {
+    if (vbasedev->ram_block_discard_allowed !=
+        group->ram_block_discard_allowed) {
         if (!QLIST_EMPTY(&group->device_list)) {
-            error_setg(errp,
-                       "Inconsistent device balloon setting within group");
+            error_setg(errp, "Inconsistent setting of support for discarding "
+                       "RAM (e.g., balloon) within group");
             close(fd);
             return -1;
         }
 
-        if (!group->balloon_allowed) {
-            group->balloon_allowed = true;
-            qemu_balloon_inhibit(false);
+        if (!group->ram_block_discard_allowed) {
+            group->ram_block_discard_allowed = true;
+            ram_block_discard_disable(false);
         }
     }