[Qemu-devel] [RFC PATCH v4] os-android: Add support to android platform

[Houcheng Lin]

Hi,

The v4 patch uses qemu_getdtablesize(), remove os-android.h and
use a local buffer when calling ptsname_r(). This patch is based
on version: 007e620a7576e4ce2ea6955541e87d8ae8ed32ae.

-----------------------------------------------------------------------

Building QEMU on android reqiures android NDK r10 cross-compilation
toolchain with following changes:

    - install qemu dependent libraries
    - upgrade bionic libc
    - add mssing includes, scsi/sg.h, in toolchain
    - make a symbolic link x86_64-linux-android-pkg-config that links
      to host's pkg-config.

Then, configure and build static linked qemu by commands:
  $ export SYSROOT="/opt/android-toolchain64/sysroot"
  $ PKG_CONFIG_LIBDIR=/opt/android-toolchain64/sysroot/usr/lib/pkgconfig \
    ./configure \
    --cross-prefix=x86_64-linux-android- --enable-kvm \
    --enable-trace-backend=nop --disable-fdt --target-list=x86_64-softmmu \
    --disable-spice --disable-vhost-net --disable-libiscsi \
    --audio-drv-list="" --disable-gtk --disable-gnutls \
    --disable-libnfs --disable-glusterfs --disable-libssh2 \
    --disable-seccomp --disable-usb-redir --disable-libusb \
    --disable-guest-agent --static
  $ make -j4

For dynamic build, you can skip the "static" option during configure, copy
dependent so files into android and add "." into LD_LIBRARY_PATH.

How to prepare your cross-compilation toolcahin
-----------------------------------------------

1. Download NDK r10, install toolchain from NDK and build the following 
libraries and install in your toolchain sysroot:
        libiconv-1.14
        gettext-0.19
        libffi-3.0.12
        glib-2.34.3
        libpng-1.2.52
        pixman-0.30

2. Download AOSP and apply this patch I made to support posix lockf()
    https://android-review.googlesource.com/#/c/172150/

3. Build bionic C and update your toolchain's libc.a and libc.so.

4. Copy kernel header file, scsi/sg.h into toolchain's 
sysroot/usr/includes/scsi/

5. Update these header files in your toolchain to prevent compilation warning,
   includes:
        unistd.h for lockf() and related define
        sys/uio.h for pread() and pwrite()
        signal.h for sigtimedwait()

Signed-off-by: Houcheng Lin <address@hidden>
---
 configure                  | 14 ++++++++++++--
 default-configs/pci.mak    |  2 +-
 hw/i386/kvm/pci-assign.c   |  1 -
 hw/xenpv/xen_domainbuild.c |  2 +-
 include/qemu/osdep.h       | 10 ++++++++++
 kvm-all.c                  |  4 ++++
 slirp/misc.c               |  2 +-
 tests/Makefile             |  2 ++
 util/oslib-posix.c         | 16 ++++++++++++++++
 util/qemu-openpty.c        | 21 ++++++++++++++++-----
 10 files changed, 63 insertions(+), 11 deletions(-)

diff --git a/configure b/configure
index d7c24cd..cda88c1 100755
--- a/configure
+++ b/configure
@@ -567,7 +567,6 @@ fi
 
 # host *BSD for user mode
 HOST_VARIANT_DIR=""
-
 case $targetos in
 CYGWIN*)
   mingw32="yes"
@@ -693,6 +692,13 @@ Haiku)
   vhost_net="yes"
   vhost_scsi="yes"
   QEMU_INCLUDES="-I\$(SRC_PATH)/linux-headers -I$(pwd)/linux-headers 
$QEMU_INCLUDES"
+  case $cross_prefix in
+    *android*)
+      android="yes"
+    ;;
+    *)
+    ;;
+  esac
 ;;
 esac
 
@@ -3791,7 +3797,7 @@ elif compile_prog "" "$pthread_lib -lrt" ; then
 fi
 
 if test "$darwin" != "yes" -a "$mingw32" != "yes" -a "$solaris" != yes -a \
-        "$aix" != "yes" -a "$haiku" != "yes" ; then
+        "$aix" != "yes" -a "$haiku" != "yes" -a "$android" != "yes" ; then
     libs_softmmu="-lutil $libs_softmmu"
 fi
 
@@ -4737,6 +4743,10 @@ if test "$linux" = "yes" ; then
   echo "CONFIG_LINUX=y" >> $config_host_mak
 fi
 
+if test "$android" = "yes" ; then
+  echo "CONFIG_ANDROID=y" >> $config_host_mak
+fi
+
 if test "$darwin" = "yes" ; then
   echo "CONFIG_DARWIN=y" >> $config_host_mak
 fi
diff --git a/default-configs/pci.mak b/default-configs/pci.mak
index 7e10903..e76dd41 100644
--- a/default-configs/pci.mak
+++ b/default-configs/pci.mak
@@ -35,5 +35,5 @@ CONFIG_SDHCI=y
 CONFIG_EDU=y
 CONFIG_VGA=y
 CONFIG_VGA_PCI=y
-CONFIG_IVSHMEM=$(CONFIG_KVM)
+CONFIG_IVSHMEM=$(call land,$(call lnot,$(CONFIG_ANDROID)),$(CONFIG_KVM))
 CONFIG_ROCKER=y
diff --git a/hw/i386/kvm/pci-assign.c b/hw/i386/kvm/pci-assign.c
index b1beaa6..44beee3 100644
--- a/hw/i386/kvm/pci-assign.c
+++ b/hw/i386/kvm/pci-assign.c
@@ -22,7 +22,6 @@
  */
 #include <stdio.h>
 #include <unistd.h>
-#include <sys/io.h>
 #include <sys/mman.h>
 #include <sys/types.h>
 #include <sys/stat.h>
diff --git a/hw/xenpv/xen_domainbuild.c b/hw/xenpv/xen_domainbuild.c
index c0ab753..480ee87 100644
--- a/hw/xenpv/xen_domainbuild.c
+++ b/hw/xenpv/xen_domainbuild.c
@@ -170,7 +170,7 @@ static int xen_domain_watcher(void)
 
     /* close all file handles, except stdio/out/err,
      * our watch pipe and the xen interface handle */
-    n = getdtablesize();
+    n = qemu_getdtablesize();
     for (i = 3; i < n; i++) {
         if (i == fd[0])
             continue;
diff --git a/include/qemu/osdep.h b/include/qemu/osdep.h
index ab3c876..9e26d10 100644
--- a/include/qemu/osdep.h
+++ b/include/qemu/osdep.h
@@ -74,6 +74,14 @@ typedef unsigned int            uint_fast16_t;
 typedef signed int              int_fast16_t;
 #endif
 
+#ifdef CONFIG_ANDROID
+/*
+ * For include the basename prototyping in android.
+ */
+#include <libgen.h>
+#define IOV_MAX 1024
+#endif
+
 #ifndef O_LARGEFILE
 #define O_LARGEFILE 0
 #endif
@@ -284,4 +292,6 @@ void os_mem_prealloc(int fd, char *area, size_t sz);
 
 int qemu_read_password(char *buf, int buf_size);
 
+int qemu_getdtablesize(void);
+
 #endif
diff --git a/kvm-all.c b/kvm-all.c
index c6f5128..f7bb9c7 100644
--- a/kvm-all.c
+++ b/kvm-all.c
@@ -45,7 +45,11 @@
 #endif
 
 /* KVM uses PAGE_SIZE in its definition of COALESCED_MMIO_MAX */
+#ifdef PAGE_SIZE
+QEMU_BUILD_BUG_ON(PAGE_SIZE != TARGET_PAGE_SIZE);
+#else
 #define PAGE_SIZE TARGET_PAGE_SIZE
+#endif
 
 //#define DEBUG_KVM
 
diff --git a/slirp/misc.c b/slirp/misc.c
index 578e8b2..47dc71d 100644
--- a/slirp/misc.c
+++ b/slirp/misc.c
@@ -170,7 +170,7 @@ fork_exec(struct socket *so, const char *ex, int do_pty)
                dup2(s, 0);
                dup2(s, 1);
                dup2(s, 2);
-               for (s = getdtablesize() - 1; s >= 3; s--)
+               for (s = qemu_getdtablesize() - 1; s >= 3; s--)
                   close(s);
 
                i = 0;
diff --git a/tests/Makefile b/tests/Makefile
index 34c6136..99faf1f 100644
--- a/tests/Makefile
+++ b/tests/Makefile
@@ -418,8 +418,10 @@ tests/test-qemu-opts$(EXESUF): tests/test-qemu-opts.o 
libqemuutil.a libqemustub.
 tests/test-write-threshold$(EXESUF): tests/test-write-threshold.o 
$(block-obj-y) libqemuutil.a libqemustub.a
 
 ifeq ($(CONFIG_POSIX),y)
+ifneq ($(CONFIG_ANDROID),y)
 LIBS += -lutil
 endif
+endif
 
 # QTest rules
 
diff --git a/util/oslib-posix.c b/util/oslib-posix.c
index 3ae4987..4ae746b 100644
--- a/util/oslib-posix.c
+++ b/util/oslib-posix.c
@@ -62,6 +62,8 @@ extern int daemon(int, int);
 #include <libgen.h>
 #include <setjmp.h>
 #include <sys/signal.h>
+#include <sys/time.h>
+#include <sys/resource.h>
 
 #ifdef CONFIG_LINUX
 #include <sys/syscall.h>
@@ -482,3 +484,17 @@ int qemu_read_password(char *buf, int buf_size)
     printf("\n");
     return ret;
 }
+
+int qemu_getdtablesize(void)
+{
+#ifdef CONFIG_ANDROID
+    struct rlimit r;
+
+    if (getrlimit(RLIMIT_NOFILE, &r) < 0) {
+        return sysconf(_SC_OPEN_MAX);
+    }
+    return r.rlim_cur;
+#else
+    return getdtablesize();
+#endif
+}
diff --git a/util/qemu-openpty.c b/util/qemu-openpty.c
index 4c53211..b305886 100644
--- a/util/qemu-openpty.c
+++ b/util/qemu-openpty.c
@@ -51,12 +51,17 @@
 # include <termios.h>
 #endif
 
-#ifdef __sun__
+#if defined(__sun__) || defined(CONFIG_ANDROID)
+
 /* Once Solaris has openpty(), this is going to be removed. */
 static int openpty(int *amaster, int *aslave, char *name,
                    struct termios *termp, struct winsize *winp)
 {
+#if defined(CONFIG_ANDROID)
+        char slave[PATH_MAX];
+#else
         const char *slave;
+#endif
         int mfd = -1, sfd = -1;
 
         *amaster = *aslave = -1;
@@ -67,17 +72,22 @@ static int openpty(int *amaster, int *aslave, char *name,
 
         if (grantpt(mfd) == -1 || unlockpt(mfd) == -1)
                 goto err;
-
+#if defined(CONFIG_ANDROID)
+        if (ptsname_r(mfd, slave, PATH_MAX) < 0)
+                goto err;
+#else
         if ((slave = ptsname(mfd)) == NULL)
                 goto err;
+#endif
 
         if ((sfd = open(slave, O_RDONLY | O_NOCTTY)) == -1)
                 goto err;
 
+#ifndef CONFIG_ANDROID
         if (ioctl(sfd, I_PUSH, "ptem") == -1 ||
             (termp != NULL && tcgetattr(sfd, termp) < 0))
                 goto err;
-
+#endif
         if (amaster)
                 *amaster = mfd;
         if (aslave)
@@ -93,7 +103,8 @@ err:
         close(mfd);
         return -1;
 }
-
+#endif
+#ifdef __sun__
 static void cfmakeraw (struct termios *termios_p)
 {
         termios_p->c_iflag &=
@@ -112,7 +123,7 @@ int qemu_openpty_raw(int *aslave, char *pty_name)
 {
     int amaster;
     struct termios tty;
-#if defined(__OpenBSD__) || defined(__DragonFly__)
+#if defined(__OpenBSD__) || defined(__DragonFly__) || defined(CONFIG_ANDROID)
     char pty_buf[PATH_MAX];
 #define q_ptsname(x) pty_buf
 #else
-- 
1.9.1