Introduce Virtio-loopback epsilon release:

Epsilon release introduces a new compatibility layer which make virtio-loopback
design to work with QEMU and rust-vmm vhost-user backend without require any
changes.

Signed-off-by: Timos Ampelikiotis <t.ampelikiotis@virtualopensystems.com>
Change-Id: I52e57563e08a7d0bdc002f8e928ee61ba0c53dd9

4 files changed, 1080 insertions, 0 deletions

diff --git a/scripts/coverity-scan/COMPONENTS.md b/scripts/coverity-scan/COMPONENTS.md
new file mode 100644
index 000000000..183f26a32
--- /dev/null
+++ b/scripts/coverity-scan/COMPONENTS.md
@@ -0,0 +1,148 @@
+This is the list of currently configured Coverity components:
+
+alpha
+  ~ (/qemu)?((/include)?/hw/alpha/.*|/target/alpha/.*)
+
+arm
+  ~ (/qemu)?((/include)?/hw/arm/.*|(/include)?/hw/.*/(arm|allwinner-a10|bcm28|digic|exynos|imx|omap|stellaris|pxa2xx|versatile|zynq|cadence).*|/hw/net/xgmac.c|/hw/ssi/xilinx_spips.c|/target/arm/.*)
+
+avr
+  ~ (/qemu)?((/include)?/hw/avr/.*|/target/avr/.*)
+
+cris
+  ~ (/qemu)?((/include)?/hw/cris/.*|/target/cris/.*)
+
+hexagon
+  ~ (/qemu)?(/target/hexagon/.*)
+
+hppa
+  ~ (/qemu)?((/include)?/hw/hppa/.*|/target/hppa/.*)
+
+i386
+  ~ (/qemu)?((/include)?/hw/i386/.*|/target/i386/.*|/hw/intc/[^/]*apic[^/]*\.c)
+
+m68k
+  ~ (/qemu)?((/include)?/hw/m68k/.*|/target/m68k/.*|(/include)?/hw(/.*)?/mcf.*)
+
+microblaze
+  ~ (/qemu)?((/include)?/hw/microblaze/.*|/target/microblaze/.*)
+
+mips
+  ~ (/qemu)?((/include)?/hw/mips/.*|/target/mips/.*)
+
+nios2
+  ~ (/qemu)?((/include)?/hw/nios2/.*|/target/nios2/.*)
+
+ppc
+  ~ (/qemu)?((/include)?/hw/ppc/.*|/target/ppc/.*|/hw/pci-host/(uninorth.*|dec.*|prep.*|ppc.*)|/hw/misc/macio/.*|(/include)?/hw/.*/(xics|openpic|spapr).*)
+
+riscv
+  ~ (/qemu)?((/include)?/hw/riscv/.*|/target/riscv/.*)
+
+rx
+  ~ (/qemu)?((/include)?/hw/rx/.*|/target/rx/.*)
+
+s390
+  ~ (/qemu)?((/include)?/hw/s390x/.*|/target/s390x/.*|/hw/.*/s390_.*)
+
+sh4
+  ~ (/qemu)?((/include)?/hw/sh4/.*|/target/sh4/.*)
+
+sparc
+  ~ (/qemu)?((/include)?/hw/sparc(64)?.*|/target/sparc/.*|/hw/.*/grlib.*|/hw/display/cg3.c)
+
+tilegx
+  ~ (/qemu)?(/target/tilegx/.*)
+
+tricore
+  ~ (/qemu)?((/include)?/hw/tricore/.*|/target/tricore/.*)
+
+9pfs
+  ~ (/qemu)?(/hw/9pfs/.*|/fsdev/.*)
+
+audio
+  ~ (/qemu)?((/include)?/(audio|hw/audio)/.*)
+
+block
+  ~ (/qemu)?(/block.*|(/include?)(/hw)?/(block|storage-daemon)/.*|(/include)?/hw/ide/.*|/qemu-(img|io).*|/util/(aio|async|thread-pool).*)
+
+char
+  ~ (/qemu)?(/qemu-char\.c|/include/sysemu/char\.h|(/include)?/hw/char/.*)
+
+capstone
+  ~ (/qemu)?(/capstone/.*)
+
+crypto
+  ~ (/qemu)?((/include)?/crypto/.*|/hw/.*/crypto.*)
+
+disas
+  ~ (/qemu)?((/include)?/disas.*)
+
+fpu
+  ~ (/qemu)?((/include)?(/fpu|/libdecnumber)/.*)
+
+io
+  ~ (/qemu)?((/include)?/io/.*)
+
+ipmi
+  ~ (/qemu)?((/include)?/hw/ipmi/.*)
+
+libvixl
+  ~ (/qemu)?(/disas/libvixl/.*)
+
+migration
+  ~ (/qemu)?((/include)?/migration/.*)
+
+monitor
+  ~ (/qemu)?(/qapi.*|/qobject/.*|/monitor\..*|/[hq]mp\..*)
+
+nbd
+  ~ (/qemu)?(/nbd/.*|/include/block/nbd.*|/qemu-nbd\.c)
+
+net
+  ~ (/qemu)?((/include)?(/hw)?/(net|rdma)/.*)
+
+pci
+  ~ (/qemu)?(/hw/pci.*|/include/hw/pci.*)
+
+qemu-ga
+  ~ (/qemu)?(/qga/.*)
+
+scsi
+  ~ (/qemu)?(/scsi/.*|/hw/scsi/.*|/include/hw/scsi/.*)
+
+slirp
+  ~ (/qemu)?(/.*slirp.*)
+
+tcg
+  ~ (/qemu)?(/accel/tcg/.*|/replay/.*|/(.*/)?softmmu.*)
+
+trace
+  ~ (/qemu)?(/.*trace.*\.[ch])
+
+ui
+  ~ (/qemu)?((/include)?(/ui|/hw/display|/hw/input)/.*)
+
+usb
+  ~ (/qemu)?(/hw/usb/.*|/include/hw/usb/.*)
+
+user
+  ~ (/qemu)?(/linux-user/.*|/bsd-user/.*|/user-exec\.c|/thunk\.c|/include/exec/user/.*)
+
+util
+  ~ (/qemu)?(/util/.*|/include/qemu/.*)
+
+xen
+  ~ (/qemu)?(.*/xen.*)
+
+virtiofsd
+  ~ (/qemu)?(/tools/virtiofsd/.*)
+
+(headers)
+  ~ (/qemu)?(/include/.*)
+
+testlibs
+  ~ (/qemu)?(/tests/qtest(/libqos/.*|/libqtest.*))
+
+tests
+  ~ (/qemu)?(/tests/.*)
diff --git a/scripts/coverity-scan/coverity-scan.docker b/scripts/coverity-scan/coverity-scan.docker
new file mode 100644
index 000000000..ecff6ac5b
--- /dev/null
+++ b/scripts/coverity-scan/coverity-scan.docker
@@ -0,0 +1,128 @@
+# syntax=docker/dockerfile:1.0.0-experimental
+#
+# Docker setup for running the "Coverity Scan" tools over the source
+# tree and uploading them to the website, as per
+# https://scan.coverity.com/projects/qemu/builds/new
+# We do this on a fixed config (currently Fedora 30 with a known
+# set of dependencies and a configure command that enables a specific
+# set of options) so that random changes don't result in our accidentally
+# dropping some files from the scan.
+#
+# We don't build on top of the fedora.docker file because we don't
+# want to accidentally change or break the scan config when that
+# is updated.
+
+# The work of actually doing the build is handled by the
+# run-coverity-scan script.
+
+FROM fedora:30
+ENV PACKAGES \
+    alsa-lib-devel \
+    bc \
+    brlapi-devel \
+    bzip2 \
+    bzip2-devel \
+    ccache \
+    clang \
+    curl \
+    cyrus-sasl-devel \
+    dbus-daemon \
+    device-mapper-multipath-devel \
+    findutils \
+    gcc \
+    gcc-c++ \
+    gettext \
+    git \
+    glib2-devel \
+    glusterfs-api-devel \
+    gnutls-devel \
+    gtk3-devel \
+    hostname \
+    libaio-devel \
+    libasan \
+    libattr-devel \
+    libblockdev-mpath-devel \
+    libcap-devel \
+    libcap-ng-devel \
+    libcurl-devel \
+    libepoxy-devel \
+    libfdt-devel \
+    libgbm-devel \
+    libiscsi-devel \
+    libjpeg-devel \
+    libpmem-devel \
+    libnfs-devel \
+    libpng-devel \
+    librbd-devel \
+    libseccomp-devel \
+    libssh-devel \
+    libubsan \
+    libudev-devel \
+    libusbx-devel \
+    libxml2-devel \
+    libzstd-devel \
+    llvm \
+    lzo-devel \
+    make \
+    mingw32-bzip2 \
+    mingw32-curl \
+    mingw32-glib2 \
+    mingw32-gmp \
+    mingw32-gnutls \
+    mingw32-gtk3 \
+    mingw32-libjpeg-turbo \
+    mingw32-libpng \
+    mingw32-libtasn1 \
+    mingw32-nettle \
+    mingw32-nsis \
+    mingw32-pixman \
+    mingw32-pkg-config \
+    mingw32-SDL2 \
+    mingw64-bzip2 \
+    mingw64-curl \
+    mingw64-glib2 \
+    mingw64-gmp \
+    mingw64-gnutls \
+    mingw64-gtk3 \
+    mingw64-libjpeg-turbo \
+    mingw64-libpng \
+    mingw64-libtasn1 \
+    mingw64-nettle \
+    mingw64-pixman \
+    mingw64-pkg-config \
+    mingw64-SDL2 \
+    ncurses-devel \
+    nettle-devel \
+    numactl-devel \
+    perl \
+    perl-Test-Harness \
+    pixman-devel \
+    pulseaudio-libs-devel \
+    python3 \
+    python3-sphinx \
+    PyYAML \
+    rdma-core-devel \
+    SDL2-devel \
+    snappy-devel \
+    sparse \
+    spice-server-devel \
+    systemd-devel \
+    systemtap-sdt-devel \
+    tar \
+    usbredir-devel \
+    virglrenderer-devel \
+    vte291-devel \
+    wget \
+    which \
+    xen-devel \
+    xfsprogs-devel \
+    zlib-devel
+ENV QEMU_CONFIGURE_OPTS --python=/usr/bin/python3
+
+RUN dnf install -y $PACKAGES
+RUN rpm -q $PACKAGES | sort > /packages.txt
+ENV PATH $PATH:/usr/libexec/python3-sphinx/
+ENV COVERITY_TOOL_BASE=/coverity-tools
+COPY coverity_tool.tgz coverity_tool.tgz
+RUN mkdir -p /coverity-tools/coverity_tool && cd /coverity-tools/coverity_tool && tar xf /coverity_tool.tgz
+COPY run-coverity-scan run-coverity-scan
diff --git a/scripts/coverity-scan/model.c b/scripts/coverity-scan/model.c
new file mode 100644
index 000000000..9d4fba53d
--- /dev/null
+++ b/scripts/coverity-scan/model.c
@@ -0,0 +1,371 @@
+/* Coverity Scan model
+ *
+ * Copyright (C) 2014 Red Hat, Inc.
+ *
+ * Authors:
+ *  Markus Armbruster <armbru@redhat.com>
+ *  Paolo Bonzini <pbonzini@redhat.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or, at your
+ * option, any later version.  See the COPYING file in the top-level directory.
+ */
+
+
+/*
+ * This is the source code for our Coverity user model file.  The
+ * purpose of user models is to increase scanning accuracy by explaining
+ * code Coverity can't see (out of tree libraries) or doesn't
+ * sufficiently understand.  Better accuracy means both fewer false
+ * positives and more true defects.  Memory leaks in particular.
+ *
+ * - A model file can't import any header files.  Some built-in primitives are
+ *   available but not wchar_t, NULL etc.
+ * - Modeling doesn't need full structs and typedefs. Rudimentary structs
+ *   and similar types are sufficient.
+ * - An uninitialized local variable signifies that the variable could be
+ *   any value.
+ *
+ * The model file must be uploaded by an admin in the analysis settings of
+ * http://scan.coverity.com/projects/378
+ */
+
+#define NULL ((void *)0)
+
+typedef unsigned char uint8_t;
+typedef char int8_t;
+typedef unsigned int uint32_t;
+typedef int int32_t;
+typedef long ssize_t;
+typedef unsigned long long uint64_t;
+typedef long long int64_t;
+typedef _Bool bool;
+
+typedef struct va_list_str *va_list;
+
+/* exec.c */
+
+typedef struct AddressSpace AddressSpace;
+typedef struct MemoryRegionCache MemoryRegionCache;
+typedef uint64_t hwaddr;
+typedef uint32_t MemTxResult;
+typedef struct MemTxAttrs {} MemTxAttrs;
+
+static void __bufwrite(uint8_t *buf, ssize_t len)
+{
+    int first, last;
+    __coverity_negative_sink__(len);
+    if (len == 0) return;
+    buf[0] = first;
+    buf[len-1] = last;
+    __coverity_writeall__(buf);
+}
+
+static void __bufread(uint8_t *buf, ssize_t len)
+{
+    __coverity_negative_sink__(len);
+    if (len == 0) return;
+    int first = buf[0];
+    int last = buf[len-1];
+}
+
+MemTxResult address_space_read_cached(MemoryRegionCache *cache, hwaddr addr,
+                                      MemTxAttrs attrs,
+                                      void *buf, int len)
+{
+    MemTxResult result;
+    // TODO: investigate impact of treating reads as producing
+    // tainted data, with __coverity_tainted_data_argument__(buf).
+    __bufwrite(buf, len);
+    return result;
+}
+
+MemTxResult address_space_write_cached(MemoryRegionCache *cache, hwaddr addr,
+                                MemTxAttrs attrs,
+                                const void *buf, int len)
+{
+    MemTxResult result;
+    __bufread(buf, len);
+    return result;
+}
+
+MemTxResult address_space_rw_cached(MemoryRegionCache *cache, hwaddr addr,
+                                    MemTxAttrs attrs,
+                                    void *buf, int len, bool is_write)
+{
+    if (is_write) {
+        return address_space_write_cached(cache, addr, attrs, buf, len);
+    } else {
+        return address_space_read_cached(cache, addr, attrs, buf, len);
+    }
+}
+
+MemTxResult address_space_read(AddressSpace *as, hwaddr addr,
+                               MemTxAttrs attrs,
+                               void *buf, int len)
+{
+    MemTxResult result;
+    // TODO: investigate impact of treating reads as producing
+    // tainted data, with __coverity_tainted_data_argument__(buf).
+    __bufwrite(buf, len);
+    return result;
+}
+
+MemTxResult address_space_write(AddressSpace *as, hwaddr addr,
+                                MemTxAttrs attrs,
+                                const void *buf, int len)
+{
+    MemTxResult result;
+    __bufread(buf, len);
+    return result;
+}
+
+MemTxResult address_space_rw(AddressSpace *as, hwaddr addr,
+                             MemTxAttrs attrs,
+                             void *buf, int len, bool is_write)
+{
+    if (is_write) {
+        return address_space_write(as, addr, attrs, buf, len);
+    } else {
+        return address_space_read(as, addr, attrs, buf, len);
+    }
+}
+
+/* Tainting */
+
+typedef struct {} name2keysym_t;
+static int get_keysym(const name2keysym_t *table,
+                      const char *name)
+{
+    int result;
+    if (result > 0) {
+        __coverity_tainted_string_sanitize_content__(name);
+        return result;
+    } else {
+        return 0;
+    }
+}
+
+/* Replay data is considered trusted.  */
+uint8_t replay_get_byte(void)
+{
+    uint8_t byte;
+    return byte;
+}
+
+
+/*
+ * GLib memory allocation functions.
+ *
+ * Note that we ignore the fact that g_malloc of 0 bytes returns NULL,
+ * and g_realloc of 0 bytes frees the pointer.
+ *
+ * Modeling this would result in Coverity flagging a lot of memory
+ * allocations as potentially returning NULL, and asking us to check
+ * whether the result of the allocation is NULL or not.  However, the
+ * resulting pointer should never be dereferenced anyway, and in fact
+ * it is not in the vast majority of cases.
+ *
+ * If a dereference did happen, this would suppress a defect report
+ * for an actual null pointer dereference.  But it's too unlikely to
+ * be worth wading through the false positives, and with some luck
+ * we'll get a buffer overflow reported anyway.
+ */
+
+/*
+ * Allocation primitives, cannot return NULL
+ * See also Coverity's library/generic/libc/all/all.c
+ */
+
+void *g_malloc_n(size_t nmemb, size_t size)
+{
+    void *ptr;
+
+    __coverity_negative_sink__(nmemb);
+    __coverity_negative_sink__(size);
+    ptr = __coverity_alloc__(nmemb * size);
+    if (!ptr) {
+        __coverity_panic__();
+    }
+    __coverity_mark_as_uninitialized_buffer__(ptr);
+    __coverity_mark_as_afm_allocated__(ptr, AFM_free);
+    return ptr;
+}
+
+void *g_malloc0_n(size_t nmemb, size_t size)
+{
+    void *ptr;
+
+    __coverity_negative_sink__(nmemb);
+    __coverity_negative_sink__(size);
+    ptr = __coverity_alloc__(nmemb * size);
+    if (!ptr) {
+        __coverity_panic__();
+    }
+    __coverity_writeall0__(ptr);
+    __coverity_mark_as_afm_allocated__(ptr, AFM_free);
+    return ptr;
+}
+
+void *g_realloc_n(void *ptr, size_t nmemb, size_t size)
+{
+    __coverity_negative_sink__(nmemb);
+    __coverity_negative_sink__(size);
+    __coverity_escape__(ptr);
+    ptr = __coverity_alloc__(nmemb * size);
+    if (!ptr) {
+        __coverity_panic__();
+    }
+    /*
+     * Memory beyond the old size isn't actually initialized.  Can't
+     * model that.  See Coverity's realloc() model
+     */
+    __coverity_writeall__(ptr);
+    __coverity_mark_as_afm_allocated__(ptr, AFM_free);
+    return ptr;
+}
+
+void g_free(void *ptr)
+{
+    __coverity_free__(ptr);
+    __coverity_mark_as_afm_freed__(ptr, AFM_free);
+}
+
+/*
+ * Derive the g_try_FOO_n() from the g_FOO_n() by adding indeterminate
+ * out of memory conditions
+ */
+
+void *g_try_malloc_n(size_t nmemb, size_t size)
+{
+    int nomem;
+
+    if (nomem) {
+        return NULL;
+    }
+    return g_malloc_n(nmemb, size);
+}
+
+void *g_try_malloc0_n(size_t nmemb, size_t size)
+{
+    int nomem;
+
+    if (nomem) {
+        return NULL;
+    }
+    return g_malloc0_n(nmemb, size);
+}
+
+void *g_try_realloc_n(void *ptr, size_t nmemb, size_t size)
+{
+    int nomem;
+
+    if (nomem) {
+        return NULL;
+    }
+    return g_realloc_n(ptr, nmemb, size);
+}
+
+/* Derive the g_FOO() from the g_FOO_n() */
+
+void *g_malloc(size_t size)
+{
+    void *ptr;
+
+    __coverity_negative_sink__(size);
+    ptr = __coverity_alloc__(size);
+    if (!ptr) {
+        __coverity_panic__();
+    }
+    __coverity_mark_as_uninitialized_buffer__(ptr);
+    __coverity_mark_as_afm_allocated__(ptr, AFM_free);
+    return ptr;
+}
+
+void *g_malloc0(size_t size)
+{
+    void *ptr;
+
+    __coverity_negative_sink__(size);
+    ptr = __coverity_alloc__(size);
+    if (!ptr) {
+        __coverity_panic__();
+    }
+    __coverity_writeall0__(ptr);
+    __coverity_mark_as_afm_allocated__(ptr, AFM_free);
+    return ptr;
+}
+
+void *g_realloc(void *ptr, size_t size)
+{
+    __coverity_negative_sink__(size);
+    __coverity_escape__(ptr);
+    ptr = __coverity_alloc__(size);
+    if (!ptr) {
+        __coverity_panic__();
+    }
+    /*
+     * Memory beyond the old size isn't actually initialized.  Can't
+     * model that.  See Coverity's realloc() model
+     */
+    __coverity_writeall__(ptr);
+    __coverity_mark_as_afm_allocated__(ptr, AFM_free);
+    return ptr;
+}
+
+void *g_try_malloc(size_t size)
+{
+    int nomem;
+
+    if (nomem) {
+        return NULL;
+    }
+    return g_malloc(size);
+}
+
+void *g_try_malloc0(size_t size)
+{
+    int nomem;
+
+    if (nomem) {
+        return NULL;
+    }
+    return g_malloc0(size);
+}
+
+void *g_try_realloc(void *ptr, size_t size)
+{
+    int nomem;
+
+    if (nomem) {
+        return NULL;
+    }
+    return g_realloc(ptr, size);
+}
+
+/* Other glib functions */
+
+typedef struct pollfd GPollFD;
+
+int poll();
+
+int g_poll (GPollFD *fds, unsigned nfds, int timeout)
+{
+    return poll(fds, nfds, timeout);
+}
+
+typedef struct _GIOChannel GIOChannel;
+GIOChannel *g_io_channel_unix_new(int fd)
+{
+    GIOChannel *c = g_malloc0(sizeof(GIOChannel));
+    __coverity_escape__(fd);
+    return c;
+}
+
+void g_assertion_message_expr(const char     *domain,
+                              const char     *file,
+                              int             line,
+                              const char     *func,
+                              const char     *expr)
+{
+    __coverity_panic__();
+}
diff --git a/scripts/coverity-scan/run-coverity-scan b/scripts/coverity-scan/run-coverity-scan
new file mode 100755
index 000000000..7395bbfad
--- /dev/null
+++ b/scripts/coverity-scan/run-coverity-scan
@@ -0,0 +1,433 @@
+#!/bin/sh -e
+
+# Upload a created tarball to Coverity Scan, as per
+# https://scan.coverity.com/projects/qemu/builds/new
+
+# This work is licensed under the terms of the GNU GPL version 2,
+# or (at your option) any later version.
+# See the COPYING file in the top-level directory.
+#
+# Copyright (c) 2017-2020 Linaro Limited
+# Written by Peter Maydell
+
+# Note that this script will automatically download and
+# run the (closed-source) coverity build tools, so don't
+# use it if you don't trust them!
+
+# This script assumes that you're running it from a QEMU source
+# tree, and that tree is a fresh clean one, because we do an in-tree
+# build. (This is necessary so that the filenames that the Coverity
+# Scan server sees are relative paths that match up with the component
+# regular expressions it uses; an out-of-tree build won't work for this.)
+# The host machine should have as many of QEMU's dependencies
+# installed as possible, for maximum coverity coverage.
+
+# To do an upload you need to be a maintainer in the Coverity online
+# service, and you will need to know the "Coverity token", which is a
+# secret 8 digit hex string. You can find that from the web UI in the
+# project settings, if you have maintainer access there.
+
+# Command line options:
+#   --dry-run : run the tools, but don't actually do the upload
+#   --docker : create and work inside a container
+#   --docker-engine : specify the container engine to use (docker/podman/auto);
+#                     implies --docker
+#   --update-tools-only : update the cached copy of the tools, but don't run them
+#   --no-update-tools : do not update the cached copy of the tools
+#   --tokenfile : file to read Coverity token from
+#   --version ver : specify version being analyzed (default: ask git)
+#   --description desc : specify description of this version (default: ask git)
+#   --srcdir : QEMU source tree to analyze (default: current working dir)
+#   --results-tarball : path to copy the results tarball to (default: don't
+#                       copy it anywhere, just upload it)
+#   --src-tarball : tarball to untar into src dir (default: none); this
+#                   is intended mainly for internal use by the Docker support
+#
+# User-specifiable environment variables:
+#  COVERITY_TOKEN -- Coverity token (default: looks at your
+#                    coverity.token config)
+#  COVERITY_EMAIL -- the email address to use for uploads (default:
+#                    looks at your git coverity.email or user.email config)
+#  COVERITY_BUILD_CMD -- make command (default: 'make -jN' where N is
+#                    number of CPUs as determined by 'nproc')
+#  COVERITY_TOOL_BASE -- set to directory to put coverity tools
+#                        (default: /tmp/coverity-tools)
+#
+# You must specify the token, either by environment variable or by
+# putting it in a file and using --tokenfile. Everything else has
+# a reasonable default if this is run from a git tree.
+
+check_upload_permissions() {
+    # Check whether we can do an upload to the server; will exit the script
+    # with status 1 if the check failed (usually a bad token);
+    # will exit the script with status 0 if the check indicated that we
+    # can't upload yet (ie we are at quota)
+    # Assumes that COVERITY_TOKEN, PROJNAME and DRYRUN have been initialized.
+
+    echo "Checking upload permissions..."
+
+    if ! up_perm="$(wget https://scan.coverity.com/api/upload_permitted --post-data "token=$COVERITY_TOKEN&project=$PROJNAME" -q -O -)"; then
+        echo "Coverity Scan API access denied: bad token?"
+        exit 1
+    fi
+
+    # Really up_perm is a JSON response with either
+    # {upload_permitted:true} or {next_upload_permitted_at:<date>}
+    # We do some hacky string parsing instead of properly parsing it.
+    case "$up_perm" in
+        *upload_permitted*true*)
+            echo "Coverity Scan: upload permitted"
+            ;;
+        *next_upload_permitted_at*)
+            if [ "$DRYRUN" = yes ]; then
+                echo "Coverity Scan: upload quota reached, continuing dry run"
+            else
+                echo "Coverity Scan: upload quota reached; stopping here"
+                # Exit success as this isn't a build error.
+                exit 0
+            fi
+            ;;
+        *)
+            echo "Coverity Scan upload check: unexpected result $up_perm"
+            exit 1
+            ;;
+    esac
+}
+
+
+build_docker_image() {
+    # build docker container including the coverity-scan tools
+    echo "Building docker container..."
+    # TODO: This re-unpacks the tools every time, rather than caching
+    # and reusing the image produced by the COPY of the .tgz file.
+    # Not sure why.
+    tests/docker/docker.py --engine ${DOCKER_ENGINE} build \
+                   -t coverity-scanner -f scripts/coverity-scan/coverity-scan.docker \
+                   --extra-files scripts/coverity-scan/run-coverity-scan \
+                                 "$COVERITY_TOOL_BASE"/coverity_tool.tgz
+}
+
+update_coverity_tools () {
+    # Check for whether we need to download the Coverity tools
+    # (either because we don't have a copy, or because it's out of date)
+    # Assumes that COVERITY_TOOL_BASE, COVERITY_TOKEN and PROJNAME are set.
+
+    mkdir -p "$COVERITY_TOOL_BASE"
+    cd "$COVERITY_TOOL_BASE"
+
+    echo "Checking for new version of coverity build tools..."
+    wget https://scan.coverity.com/download/linux64 --post-data "token=$COVERITY_TOKEN&project=$PROJNAME&md5=1" -O coverity_tool.md5.new
+
+    if ! cmp -s coverity_tool.md5 coverity_tool.md5.new; then
+        # out of date md5 or no md5: download new build tool
+        # blow away the old build tool
+        echo "Downloading coverity build tools..."
+        rm -rf coverity_tool coverity_tool.tgz
+        wget https://scan.coverity.com/download/linux64 --post-data "token=$COVERITY_TOKEN&project=$PROJNAME" -O coverity_tool.tgz
+        if ! (cat coverity_tool.md5.new; echo "  coverity_tool.tgz") | md5sum -c --status; then
+            echo "Downloaded tarball didn't match md5sum!"
+            exit 1
+        fi
+
+        if [ "$DOCKER" != yes ]; then
+            # extract the new one, keeping it corralled in a 'coverity_tool' directory
+            echo "Unpacking coverity build tools..."
+            mkdir -p coverity_tool
+            cd coverity_tool
+            tar xf ../coverity_tool.tgz
+            cd ..
+            mv coverity_tool.md5.new coverity_tool.md5
+        fi
+    fi
+    rm -f coverity_tool.md5.new
+    cd "$SRCDIR"
+
+    if [ "$DOCKER" = yes ]; then
+        build_docker_image
+    fi
+}
+
+
+# Check user-provided environment variables and arguments
+DRYRUN=no
+UPDATE=yes
+DOCKER=no
+
+while [ "$#" -ge 1 ]; do
+    case "$1" in
+        --dry-run)
+            shift
+            DRYRUN=yes
+            ;;
+        --no-update-tools)
+            shift
+            UPDATE=no
+            ;;
+        --update-tools-only)
+            shift
+            UPDATE=only
+            ;;
+        --version)
+            shift
+            if [ $# -eq 0 ]; then
+                echo "--version needs an argument"
+                exit 1
+            fi
+            VERSION="$1"
+            shift
+            ;;
+        --description)
+            shift
+            if [ $# -eq 0 ]; then
+                echo "--description needs an argument"
+                exit 1
+            fi
+            DESCRIPTION="$1"
+            shift
+            ;;
+        --tokenfile)
+            shift
+            if [ $# -eq 0 ]; then
+                echo "--tokenfile needs an argument"
+                exit 1
+            fi
+            COVERITY_TOKEN="$(cat "$1")"
+            shift
+            ;;
+        --srcdir)
+            shift
+            if [ $# -eq 0 ]; then
+                echo "--srcdir needs an argument"
+                exit 1
+            fi
+            SRCDIR="$1"
+            shift
+            ;;
+        --results-tarball)
+            shift
+            if [ $# -eq 0 ]; then
+                echo "--results-tarball needs an argument"
+                exit 1
+            fi
+            RESULTSTARBALL="$1"
+            shift
+            ;;
+        --src-tarball)
+            shift
+            if [ $# -eq 0 ]; then
+                echo "--src-tarball needs an argument"
+                exit 1
+            fi
+            SRCTARBALL="$1"
+            shift
+            ;;
+        --docker)
+            DOCKER=yes
+            DOCKER_ENGINE=auto
+            shift
+            ;;
+        --docker-engine)
+            shift
+            if [ $# -eq 0 ]; then
+                echo "--docker-engine needs an argument"
+                exit 1
+            fi
+            DOCKER=yes
+            DOCKER_ENGINE="$1"
+            shift
+            ;;
+        *)
+            echo "Unexpected argument '$1'"
+            exit 1
+            ;;
+    esac
+done
+
+if [ -z "$COVERITY_TOKEN" ]; then
+    COVERITY_TOKEN="$(git config coverity.token)"
+fi
+if [ -z "$COVERITY_TOKEN" ]; then
+    echo "COVERITY_TOKEN environment variable not set"
+    exit 1
+fi
+
+if [ -z "$COVERITY_BUILD_CMD" ]; then
+    NPROC=$(nproc)
+    COVERITY_BUILD_CMD="make -j$NPROC"
+    echo "COVERITY_BUILD_CMD: using default '$COVERITY_BUILD_CMD'"
+fi
+
+if [ -z "$COVERITY_TOOL_BASE" ]; then
+    echo "COVERITY_TOOL_BASE: using default /tmp/coverity-tools"
+    COVERITY_TOOL_BASE=/tmp/coverity-tools
+fi
+
+if [ -z "$SRCDIR" ]; then
+    SRCDIR="$PWD"
+fi
+
+PROJNAME=QEMU
+TARBALL=cov-int.tar.xz
+
+if [ "$UPDATE" = only ]; then
+    # Just do the tools update; we don't need to check whether
+    # we are in a source tree or have upload rights for this,
+    # so do it before some of the command line and source tree checks.
+
+    if [ "$DOCKER" = yes ] && [ ! -z "$SRCTARBALL" ]; then
+        echo --update-tools-only --docker is incompatible with --src-tarball.
+        exit 1
+    fi
+
+    update_coverity_tools
+    exit 0
+fi
+
+if [ ! -e "$SRCDIR" ]; then
+    mkdir "$SRCDIR"
+fi
+
+cd "$SRCDIR"
+
+if [ ! -z "$SRCTARBALL" ]; then
+    echo "Untarring source tarball into $SRCDIR..."
+    tar xvf "$SRCTARBALL"
+fi
+
+echo "Checking this is a QEMU source tree..."
+if ! [ -e "$SRCDIR/VERSION" ]; then
+    echo "Not in a QEMU source tree?"
+    exit 1
+fi
+
+# Fill in defaults used by the non-update-only process
+if [ -z "$VERSION" ]; then
+    VERSION="$(git describe --always HEAD)"
+fi
+
+if [ -z "$DESCRIPTION" ]; then
+    DESCRIPTION="$(git rev-parse HEAD)"
+fi
+
+if [ -z "$COVERITY_EMAIL" ]; then
+    COVERITY_EMAIL="$(git config coverity.email)"
+fi
+if [ -z "$COVERITY_EMAIL" ]; then
+    COVERITY_EMAIL="$(git config user.email)"
+fi
+
+# Otherwise, continue with the full build and upload process.
+
+check_upload_permissions
+
+if [ "$UPDATE" != no ]; then
+    update_coverity_tools
+fi
+
+# Run ourselves inside docker if that's what the user wants
+if [ "$DOCKER" = yes ]; then
+    # Put the Coverity token into a temporary file that only
+    # we have read access to, and then pass it to docker build
+    # using a volume.  A volume is enough for the token not to
+    # leak into the Docker image.
+    umask 077
+    SECRETDIR=$(mktemp -d)
+    if [ -z "$SECRETDIR" ]; then
+        echo "Failed to create temporary directory"
+        exit 1
+    fi
+    trap 'rm -rf "$SECRETDIR"' INT TERM EXIT
+    echo "Created temporary directory $SECRETDIR"
+    SECRET="$SECRETDIR/token"
+    echo "$COVERITY_TOKEN" > "$SECRET"
+    echo "Archiving sources to be analyzed..."
+    ./scripts/archive-source.sh "$SECRETDIR/qemu-sources.tgz"
+    ARGS="--no-update-tools"
+    if [ "$DRYRUN" = yes ]; then
+        ARGS="$ARGS --dry-run"
+    fi
+    echo "Running scanner..."
+    # If we need to capture the output tarball, get the inner run to
+    # save it to the secrets directory so we can copy it out before the
+    # directory is cleaned up.
+    if [ ! -z "$RESULTSTARBALL" ]; then
+        ARGS="$ARGS --results-tarball /work/cov-int.tar.xz"
+    fi
+    # Arrange for this docker run to get access to the sources with -v.
+    # We pass through all the configuration from the outer script to the inner.
+    export COVERITY_EMAIL COVERITY_BUILD_CMD
+    tests/docker/docker.py run -it --env COVERITY_EMAIL --env COVERITY_BUILD_CMD \
+           -v "$SECRETDIR:/work" coverity-scanner \
+           ./run-coverity-scan --version "$VERSION" \
+           --description "$DESCRIPTION" $ARGS --tokenfile /work/token \
+           --srcdir /qemu --src-tarball /work/qemu-sources.tgz
+    if [ ! -z "$RESULTSTARBALL" ]; then
+        echo "Copying results tarball to $RESULTSTARBALL..."
+        cp "$SECRETDIR/cov-int.tar.xz" "$RESULTSTARBALL"
+    fi
+    echo "Docker work complete."
+    exit 0
+fi
+
+TOOLBIN="$(cd "$COVERITY_TOOL_BASE" && echo $PWD/coverity_tool/cov-analysis-*/bin)"
+
+if ! test -x "$TOOLBIN/cov-build"; then
+    echo "Couldn't find cov-build in the coverity build-tool directory??"
+    exit 1
+fi
+
+export PATH="$TOOLBIN:$PATH"
+
+cd "$SRCDIR"
+
+echo "Nuking build directory..."
+rm -rf +build
+mkdir +build
+cd +build
+
+echo "Configuring..."
+# We configure with a fixed set of enables here to ensure that we don't
+# accidentally reduce the scope of the analysis by doing the build on
+# the system that's missing a dependency that we need to build part of
+# the codebase.
+../configure --disable-modules --enable-sdl --enable-gtk \
+    --enable-opengl --enable-vte --enable-gnutls \
+    --enable-nettle --enable-curses --enable-curl \
+    --audio-drv-list=oss,alsa,sdl,pa --enable-virtfs \
+    --enable-vnc --enable-vnc-sasl --enable-vnc-jpeg --enable-vnc-png \
+    --enable-xen --enable-brlapi \
+    --enable-linux-aio --enable-attr \
+    --enable-cap-ng --enable-trace-backends=log --enable-spice --enable-rbd \
+    --enable-xfsctl --enable-libusb --enable-usb-redir \
+    --enable-libiscsi --enable-libnfs --enable-seccomp \
+    --enable-tpm --enable-libssh --enable-lzo --enable-snappy --enable-bzip2 \
+    --enable-numa --enable-rdma --enable-smartcard --enable-virglrenderer \
+    --enable-mpath --enable-libxml2 --enable-glusterfs \
+    --enable-virtfs --enable-zstd
+
+echo "Running cov-build..."
+rm -rf cov-int
+mkdir cov-int
+cov-build --dir cov-int $COVERITY_BUILD_CMD
+
+echo "Creating results tarball..."
+tar cvf - cov-int | xz > "$TARBALL"
+
+if [ ! -z "$RESULTSTARBALL" ]; then
+    echo "Copying results tarball to $RESULTSTARBALL..."
+    cp "$TARBALL" "$RESULTSTARBALL"
+fi
+
+echo "Uploading results tarball..."
+
+if [ "$DRYRUN" = yes ]; then
+    echo "Dry run only, not uploading $TARBALL"
+    exit 0
+fi
+
+curl --form token="$COVERITY_TOKEN" --form email="$COVERITY_EMAIL" \
+     --form file=@"$TARBALL" --form version="$VERSION" \
+     --form description="$DESCRIPTION" \
+     https://scan.coverity.com/builds?project="$PROJNAME"
+
+echo "Done."