Add mremap tests

Add tests for MREMAP_MAYMOVE and MREMAP_FIXED.  On Linux, also test
MREMAP_DONTUNMAP.

Signed-off-by: H.J. Lu <hjl.tools@gmail.com>
Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
(cherry picked from commit ff0320bec2810192d453c579623482fab87bfa01)

7 files changed, 220 insertions, 1 deletions

diff --git a/misc/Makefile b/misc/Makefile
index 66e9ded..e77cdd8 100644
--- a/misc/Makefile
+++ b/misc/Makefile
@@ -90,7 +90,7 @@ tests := tst-dirname tst-tsearch tst-fdset tst-mntent tst-hsearch \
 	 tst-preadvwritev2 tst-preadvwritev64v2 tst-warn-wide \
 	 tst-ldbl-warn tst-ldbl-error tst-dbl-efgcvt tst-ldbl-efgcvt \
 	 tst-mntent-autofs tst-syscalls tst-mntent-escape tst-select \
-	 tst-ioctl
+	 tst-ioctl tst-mremap1 tst-mremap2
 
 tests-time64 := \
   tst-select-time64 \
diff --git a/misc/tst-mremap1.c b/misc/tst-mremap1.c
new file mode 100644
index 0000000..0469991
--- /dev/null
+++ b/misc/tst-mremap1.c
@@ -0,0 +1,46 @@
+/* Test mremap with MREMAP_MAYMOVE.
+   Copyright (C) 2024 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <https://www.gnu.org/licenses/>.  */
+
+#include <errno.h>
+#include <sys/mman.h>
+#include <support/xstdlib.h>
+#include <support/xunistd.h>
+#include <support/check.h>
+#include <support/test-driver.h>
+
+static int
+do_test (void)
+{
+  size_t old_size = getpagesize ();
+  char *old_addr = xmmap (NULL, old_size, PROT_READ | PROT_WRITE,
+			  MAP_PRIVATE | MAP_ANONYMOUS, -1);
+  old_addr[0] = 1;
+  old_addr[old_size - 1] = 2;
+
+  /* Test MREMAP_MAYMOVE.  */
+  size_t new_size = old_size + old_size;
+  char *new_addr = mremap (old_addr, old_size, new_size, MREMAP_MAYMOVE);
+  TEST_VERIFY_EXIT (new_addr != MAP_FAILED);
+  new_addr[0] = 1;
+  new_addr[new_size - 1] = 2;
+  xmunmap (new_addr, new_size);
+
+  return 0;
+}
+
+#include <support/test-driver.c>
diff --git a/misc/tst-mremap2.c b/misc/tst-mremap2.c
new file mode 100644
index 0000000..45be7f0
--- /dev/null
+++ b/misc/tst-mremap2.c
@@ -0,0 +1,54 @@
+/* Test mremap with MREMAP_FIXED.
+   Copyright (C) 2024 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <https://www.gnu.org/licenses/>.  */
+
+#include <errno.h>
+#include <sys/mman.h>
+#include <support/xstdlib.h>
+#include <support/xunistd.h>
+#include <support/test-driver.h>
+#include <mremap-failure.h>
+
+static int
+do_test (void)
+{
+  size_t old_size = getpagesize ();
+  size_t new_size = old_size + old_size;
+  char *old_addr = xmmap (NULL, old_size, PROT_READ | PROT_WRITE,
+			  MAP_PRIVATE | MAP_ANONYMOUS, -1);
+  old_addr[0] = 1;
+  old_addr[old_size - 1] = 2;
+
+  char *fixed_addr = xmmap (NULL, new_size, PROT_READ | PROT_WRITE,
+			    MAP_PRIVATE | MAP_ANONYMOUS, -1);
+  fixed_addr[0] = 1;
+  fixed_addr[new_size - 1] = 2;
+
+  /* Test MREMAP_FIXED.  */
+  char *new_addr = mremap (old_addr, old_size, new_size,
+			   MREMAP_FIXED | MREMAP_MAYMOVE,
+			   fixed_addr);
+  if (new_addr == MAP_FAILED)
+    return mremap_failure_exit (errno);
+  new_addr[0] = 1;
+  new_addr[new_size - 1] = 2;
+  xmunmap (new_addr, new_size);
+
+  return 0;
+}
+
+#include <support/test-driver.c>
diff --git a/sysdeps/generic/mremap-failure.h b/sysdeps/generic/mremap-failure.h
new file mode 100644
index 0000000..bc0d476
--- /dev/null
+++ b/sysdeps/generic/mremap-failure.h
@@ -0,0 +1,25 @@
+/* mremap failure handling.  Generic version.
+   Copyright (C) 2024 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <https://www.gnu.org/licenses/>.  */
+
+/* Return exit value on mremap failure with errno ERR.  */
+
+static int
+mremap_failure_exit (int err)
+{
+  return EXIT_FAILURE;
+}
diff --git a/sysdeps/unix/sysv/linux/Makefile b/sysdeps/unix/sysv/linux/Makefile
index a039048..d92ea7a 100644
--- a/sysdeps/unix/sysv/linux/Makefile
+++ b/sysdeps/unix/sysv/linux/Makefile
@@ -131,6 +131,7 @@ tests += tst-clone tst-clone2 tst-clone3 tst-fanotify tst-personality \
   tst-pidfd \
   tst-process_mrelease \
   tst-mount \
+  tst-linux-mremap1 \
   # tests
 
 # process_madvise requires CAP_SYS_ADMIN.
diff --git a/sysdeps/unix/sysv/linux/mremap-failure.h b/sysdeps/unix/sysv/linux/mremap-failure.h
new file mode 100644
index 0000000..c99ab30
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/mremap-failure.h
@@ -0,0 +1,30 @@
+/* mremap failure handling.  Linux version.
+   Copyright (C) 2024 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <https://www.gnu.org/licenses/>.  */
+
+#include <support/check.h>
+
+/* Return exit value on mremap failure with errno ERR.  */
+
+static int
+mremap_failure_exit (int err)
+{
+  if (err != EINVAL)
+    return EXIT_FAILURE;
+
+  return EXIT_UNSUPPORTED;
+}
diff --git a/sysdeps/unix/sysv/linux/tst-linux-mremap1.c b/sysdeps/unix/sysv/linux/tst-linux-mremap1.c
new file mode 100644
index 0000000..408e8af
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/tst-linux-mremap1.c
@@ -0,0 +1,63 @@
+/* Test mremap with MREMAP_DONTUNMAP.
+   Copyright (C) 2024 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <https://www.gnu.org/licenses/>.  */
+
+#include <errno.h>
+#include <sys/mman.h>
+#include <support/xstdlib.h>
+#include <support/xunistd.h>
+#include <support/check.h>
+#include <support/test-driver.h>
+#include <mremap-failure.h>
+
+static int
+do_test (void)
+{
+  size_t old_size = getpagesize ();
+  size_t new_size = old_size;
+  char *old_addr = xmmap (NULL, old_size, PROT_READ | PROT_WRITE,
+			  MAP_PRIVATE | MAP_ANONYMOUS, -1);
+  old_addr[0] = 1;
+  old_addr[old_size - 1] = 2;
+
+  /* Create an available 64-page mmap region.  */
+  size_t fixed_size = old_size * 64;
+  char *fixed_addr = xmmap (NULL, fixed_size, PROT_READ | PROT_WRITE,
+			    MAP_PRIVATE | MAP_ANONYMOUS, -1);
+  xmunmap (fixed_addr, fixed_size);
+
+  /* Add 3 * pagesize.  */
+  fixed_size += 3 * old_size;
+
+  /* Test MREMAP_DONTUNMAP.  It should return FIXED_ADDR created above.  */
+  char *new_addr = mremap (old_addr, old_size, new_size,
+			   MREMAP_DONTUNMAP | MREMAP_MAYMOVE,
+			   fixed_addr);
+  if (new_addr == MAP_FAILED)
+    return mremap_failure_exit (errno);
+  TEST_VERIFY_EXIT (fixed_addr == new_addr);
+  old_addr[0] = 3;
+  old_addr[old_size - 1] = 4;
+  new_addr[0] = 1;
+  new_addr[new_size - 1] = 2;
+  xmunmap (new_addr, new_size);
+  xmunmap (old_addr, old_size);
+
+  return 0;
+}
+
+#include <support/test-driver.c>