linux-user/aarch64: Add vdso
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
diff --git a/linux-user/aarch64/Makefile.vdso b/linux-user/aarch64/Makefile.vdso
new file mode 100644
index 0000000..5999581
--- /dev/null
+++ b/linux-user/aarch64/Makefile.vdso
@@ -0,0 +1,15 @@
+include $(BUILD_DIR)/tests/tcg/aarch64-linux-user/config-target.mak
+
+SUBDIR = $(SRC_PATH)/linux-user/aarch64
+VPATH += $(SUBDIR)
+
+all: $(SUBDIR)/vdso-be.so $(SUBDIR)/vdso-le.so
+
+LDFLAGS = -nostdlib -shared -Wl,-h,linux-vdso.so.1 -Wl,--build-id=sha1 \
+ -Wl,--hash-style=both -Wl,-T,$(SUBDIR)/vdso.ld
+
+$(SUBDIR)/vdso-be.so: vdso.S vdso.ld
+ $(CC) -o $@ $(LDFLAGS) -mbig-endian $<
+
+$(SUBDIR)/vdso-le.so: vdso.S vdso.ld
+ $(CC) -o $@ $(LDFLAGS) -mlittle-endian $<
diff --git a/linux-user/aarch64/meson.build b/linux-user/aarch64/meson.build
new file mode 100644
index 0000000..248c578
--- /dev/null
+++ b/linux-user/aarch64/meson.build
@@ -0,0 +1,11 @@
+# TARGET_BIG_ENDIAN is defined to 'n' for little-endian; which means it
+# is always true as far as source_set.apply() is concerned. Always build
+# both header files and include the right one via #if.
+
+vdso_be_inc = gen_vdso.process('vdso-be.so',
+ extra_args: ['-r', '__kernel_rt_sigreturn'])
+
+vdso_le_inc = gen_vdso.process('vdso-le.so',
+ extra_args: ['-r', '__kernel_rt_sigreturn'])
+
+linux_user_ss.add(when: 'TARGET_AARCH64', if_true: [vdso_be_inc, vdso_le_inc])
diff --git a/linux-user/aarch64/vdso-be.so b/linux-user/aarch64/vdso-be.so
new file mode 100755
index 0000000..6084f3d
--- /dev/null
+++ b/linux-user/aarch64/vdso-be.so
Binary files differ
diff --git a/linux-user/aarch64/vdso-le.so b/linux-user/aarch64/vdso-le.so
new file mode 100755
index 0000000..947d534
--- /dev/null
+++ b/linux-user/aarch64/vdso-le.so
Binary files differ
diff --git a/linux-user/aarch64/vdso.S b/linux-user/aarch64/vdso.S
new file mode 100644
index 0000000..34d3a9e
--- /dev/null
+++ b/linux-user/aarch64/vdso.S
@@ -0,0 +1,71 @@
+/*
+ * aarch64 linux replacement vdso.
+ *
+ * Copyright 2023 Linaro, Ltd.
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+
+#include <asm/unistd.h>
+
+/* ??? These are in include/elf.h, which is not ready for inclusion in asm. */
+#define NT_GNU_PROPERTY_TYPE_0 5
+#define GNU_PROPERTY_AARCH64_FEATURE_1_AND 0xc0000000
+#define GNU_PROPERTY_AARCH64_FEATURE_1_BTI (1U << 0)
+#define GNU_PROPERTY_AARCH64_FEATURE_1_PAC (1U << 1)
+
+#define GNU_PROPERTY_AARCH64_FEATURE_1_DEFAULT \
+ (GNU_PROPERTY_AARCH64_FEATURE_1_BTI | GNU_PROPERTY_AARCH64_FEATURE_1_PAC)
+
+ .section .note.gnu.property
+ .align 3
+ .long 2f - 1f
+ .long 6f - 3f
+ .long NT_GNU_PROPERTY_TYPE_0
+1: .string "GNU"
+2: .align 3
+3: .long GNU_PROPERTY_AARCH64_FEATURE_1_AND
+ .long 5f - 4f
+4: .long GNU_PROPERTY_AARCH64_FEATURE_1_DEFAULT
+5: .align 3
+6:
+
+ .text
+
+.macro endf name
+ .globl \name
+ .type \name, @function
+ .size \name, . - \name
+.endm
+
+.macro vdso_syscall name, nr
+\name:
+ bti c
+ mov x8, #\nr
+ svc #0
+ ret
+endf \name
+.endm
+
+ .cfi_startproc
+
+vdso_syscall __kernel_gettimeofday, __NR_gettimeofday
+vdso_syscall __kernel_clock_gettime, __NR_clock_gettime
+vdso_syscall __kernel_clock_getres, __NR_clock_getres
+
+ .cfi_endproc
+
+
+/*
+ * TODO: The kernel makes a big deal of turning off the .cfi directives,
+ * because they cause libgcc to crash, but that's because they're wrong.
+ *
+ * For now, elide the unwind info for __kernel_rt_sigreturn and rely on
+ * the libgcc fallback routine as we have always done. This requires
+ * that the code sequence used be exact.
+ */
+__kernel_rt_sigreturn:
+ /* No BTI C insn here -- we arrive via RET. */
+ mov x8, #__NR_rt_sigreturn
+ svc #0
+endf __kernel_rt_sigreturn
diff --git a/linux-user/aarch64/vdso.ld b/linux-user/aarch64/vdso.ld
new file mode 100644
index 0000000..4c12f33
--- /dev/null
+++ b/linux-user/aarch64/vdso.ld
@@ -0,0 +1,72 @@
+/*
+ * Linker script for linux aarch64 replacement vdso.
+ *
+ * Copyright 2021 Linaro, Ltd.
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+
+VERSION {
+ LINUX_2.6.39 {
+ global:
+ __kernel_rt_sigreturn;
+ __kernel_gettimeofday;
+ __kernel_clock_gettime;
+ __kernel_clock_getres;
+
+ local: *;
+ };
+}
+
+
+PHDRS {
+ phdr PT_PHDR FLAGS(4) PHDRS;
+ load PT_LOAD FLAGS(7) FILEHDR PHDRS;
+ dynamic PT_DYNAMIC FLAGS(4);
+ eh_frame_hdr PT_GNU_EH_FRAME;
+ note PT_NOTE FLAGS(4);
+}
+
+SECTIONS {
+ /*
+ * We can't prelink to any address without knowing something about
+ * the virtual memory space of the host, since that leaks over into
+ * the available memory space of the guest.
+ */
+ . = SIZEOF_HEADERS;
+
+ /*
+ * The following, including the FILEHDRS and PHDRS, are modified
+ * when we relocate the binary. We want them to be initially
+ * writable for the relocation; we'll force them read-only after.
+ */
+ .note : { *(.note*) } :load :note
+ .dynamic : { *(.dynamic) } :load :dynamic
+ .dynsym : { *(.dynsym) } :load
+ /*
+ * There ought not be any real read-write data.
+ * But since we manipulated the segment layout,
+ * we have to put these sections somewhere.
+ */
+ .data : {
+ *(.data*)
+ *(.sdata*)
+ *(.got.plt) *(.got)
+ *(.gnu.linkonce.d.*)
+ *(.bss*)
+ *(.dynbss*)
+ *(.gnu.linkonce.b.*)
+ }
+
+ .rodata : { *(.rodata*) }
+ .hash : { *(.hash) }
+ .gnu.hash : { *(.gnu.hash) }
+ .dynstr : { *(.dynstr) }
+ .gnu.version : { *(.gnu.version) }
+ .gnu.version_d : { *(.gnu.version_d) }
+ .gnu.version_r : { *(.gnu.version_r) }
+ .eh_frame_hdr : { *(.eh_frame_hdr) } :load :eh_frame_hdr
+ .eh_frame : { *(.eh_frame) } :load
+
+ .text : { *(.text*) } :load =0xd503201f
+}
diff --git a/linux-user/elfload.c b/linux-user/elfload.c
index 62a3348..0a3a570 100644
--- a/linux-user/elfload.c
+++ b/linux-user/elfload.c
@@ -944,6 +944,12 @@
#undef GET_FEATURE_ID
+#if TARGET_BIG_ENDIAN
+# define VDSO_HEADER "vdso-be.c.inc"
+#else
+# define VDSO_HEADER "vdso-le.c.inc"
+#endif
+
#endif /* not TARGET_AARCH64 */
#endif /* TARGET_ARM */
diff --git a/linux-user/meson.build b/linux-user/meson.build
index e4cb70e..dd24389 100644
--- a/linux-user/meson.build
+++ b/linux-user/meson.build
@@ -35,6 +35,7 @@
gen_vdso = generator(gen_vdso_exe, output: '@BASENAME@.c.inc',
arguments: ['-o', '@OUTPUT@', '@EXTRA_ARGS@', '@INPUT@'])
+subdir('aarch64')
subdir('alpha')
subdir('arm')
subdir('hppa')
