summaryrefslogtreecommitdiffstats
path: root/arch/s390/kernel/vdso64
diff options
context:
space:
mode:
Diffstat (limited to 'arch/s390/kernel/vdso64')
-rw-r--r--arch/s390/kernel/vdso64/.gitignore2
-rw-r--r--arch/s390/kernel/vdso64/Makefile75
-rw-r--r--arch/s390/kernel/vdso64/getcpu.S31
-rw-r--r--arch/s390/kernel/vdso64/note.S13
-rw-r--r--arch/s390/kernel/vdso64/vdso64.lds.S142
-rw-r--r--arch/s390/kernel/vdso64/vdso64_generic.c18
-rw-r--r--arch/s390/kernel/vdso64/vdso64_wrapper.S15
-rw-r--r--arch/s390/kernel/vdso64/vdso_user_wrapper.S38
8 files changed, 334 insertions, 0 deletions
diff --git a/arch/s390/kernel/vdso64/.gitignore b/arch/s390/kernel/vdso64/.gitignore
new file mode 100644
index 000000000..4ec80685f
--- /dev/null
+++ b/arch/s390/kernel/vdso64/.gitignore
@@ -0,0 +1,2 @@
+# SPDX-License-Identifier: GPL-2.0-only
+vdso64.lds
diff --git a/arch/s390/kernel/vdso64/Makefile b/arch/s390/kernel/vdso64/Makefile
new file mode 100644
index 000000000..13cc5a3f9
--- /dev/null
+++ b/arch/s390/kernel/vdso64/Makefile
@@ -0,0 +1,75 @@
+# SPDX-License-Identifier: GPL-2.0
+# List of files in the vdso
+
+KCOV_INSTRUMENT := n
+ARCH_REL_TYPE_ABS := R_390_COPY|R_390_GLOB_DAT|R_390_JMP_SLOT|R_390_RELATIVE
+ARCH_REL_TYPE_ABS += R_390_GOT|R_390_PLT
+
+include $(srctree)/lib/vdso/Makefile
+obj-vdso64 = vdso_user_wrapper.o note.o getcpu.o
+obj-cvdso64 = vdso64_generic.o
+CFLAGS_REMOVE_vdso64_generic.o = -pg $(CC_FLAGS_FTRACE) $(CC_FLAGS_EXPOLINE)
+
+# Build rules
+
+targets := $(obj-vdso64) $(obj-cvdso64) vdso64.so vdso64.so.dbg
+obj-vdso64 := $(addprefix $(obj)/, $(obj-vdso64))
+obj-cvdso64 := $(addprefix $(obj)/, $(obj-cvdso64))
+
+KBUILD_AFLAGS += -DBUILD_VDSO
+KBUILD_CFLAGS += -DBUILD_VDSO -DDISABLE_BRANCH_PROFILING
+
+KBUILD_AFLAGS_64 := $(filter-out -m64,$(KBUILD_AFLAGS))
+KBUILD_AFLAGS_64 += -m64 -s
+
+KBUILD_CFLAGS_64 := $(filter-out -m64,$(KBUILD_CFLAGS))
+KBUILD_CFLAGS_64 += -m64 -fPIC -shared -fno-common -fno-builtin
+ldflags-y := -fPIC -shared -nostdlib -soname=linux-vdso64.so.1 \
+ --hash-style=both --build-id=sha1 -T
+
+$(targets:%=$(obj)/%.dbg): KBUILD_CFLAGS = $(KBUILD_CFLAGS_64)
+$(targets:%=$(obj)/%.dbg): KBUILD_AFLAGS = $(KBUILD_AFLAGS_64)
+
+obj-y += vdso64_wrapper.o
+targets += vdso64.lds
+CPPFLAGS_vdso64.lds += -P -C -U$(ARCH)
+
+# Disable gcov profiling, ubsan and kasan for VDSO code
+GCOV_PROFILE := n
+UBSAN_SANITIZE := n
+KASAN_SANITIZE := n
+
+# Force dependency (incbin is bad)
+$(obj)/vdso64_wrapper.o : $(obj)/vdso64.so
+
+# link rule for the .so file, .lds has to be first
+$(obj)/vdso64.so.dbg: $(src)/vdso64.lds $(obj-vdso64) $(obj-cvdso64) FORCE
+ $(call if_changed,ld)
+
+# strip rule for the .so file
+$(obj)/%.so: OBJCOPYFLAGS := -S
+$(obj)/%.so: $(obj)/%.so.dbg FORCE
+ $(call if_changed,objcopy)
+
+# assembly rules for the .S files
+$(obj-vdso64): %.o: %.S FORCE
+ $(call if_changed_dep,vdso64as)
+
+$(obj-cvdso64): %.o: %.c FORCE
+ $(call if_changed_dep,vdso64cc)
+
+# actual build commands
+quiet_cmd_vdso64as = VDSO64A $@
+ cmd_vdso64as = $(CC) $(a_flags) -c -o $@ $<
+quiet_cmd_vdso64cc = VDSO64C $@
+ cmd_vdso64cc = $(CC) $(c_flags) -c -o $@ $<
+
+# install commands for the unstripped file
+quiet_cmd_vdso_install = INSTALL $@
+ cmd_vdso_install = cp $(obj)/$@.dbg $(MODLIB)/vdso/$@
+
+vdso64.so: $(obj)/vdso64.so.dbg
+ @mkdir -p $(MODLIB)/vdso
+ $(call cmd,vdso_install)
+
+vdso_install: vdso64.so
diff --git a/arch/s390/kernel/vdso64/getcpu.S b/arch/s390/kernel/vdso64/getcpu.S
new file mode 100644
index 000000000..3c04f7328
--- /dev/null
+++ b/arch/s390/kernel/vdso64/getcpu.S
@@ -0,0 +1,31 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Userland implementation of getcpu() for 64 bits processes in a
+ * s390 kernel for use in the vDSO
+ *
+ * Copyright IBM Corp. 2016
+ * Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>
+ */
+#include <asm/vdso.h>
+#include <asm/asm-offsets.h>
+#include <asm/dwarf.h>
+
+ .text
+ .align 4
+ .globl __kernel_getcpu
+ .type __kernel_getcpu,@function
+__kernel_getcpu:
+ CFI_STARTPROC
+ sacf 256
+ lm %r4,%r5,__VDSO_GETCPU_VAL(%r0)
+ sacf 0
+ ltgr %r2,%r2
+ jz 2f
+ st %r5,0(%r2)
+2: ltgr %r3,%r3
+ jz 3f
+ st %r4,0(%r3)
+3: lghi %r2,0
+ br %r14
+ CFI_ENDPROC
+ .size __kernel_getcpu,.-__kernel_getcpu
diff --git a/arch/s390/kernel/vdso64/note.S b/arch/s390/kernel/vdso64/note.S
new file mode 100644
index 000000000..db19d0680
--- /dev/null
+++ b/arch/s390/kernel/vdso64/note.S
@@ -0,0 +1,13 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * This supplies .note.* sections to go into the PT_NOTE inside the vDSO text.
+ * Here we can supply some information useful to userland.
+ */
+
+#include <linux/uts.h>
+#include <linux/version.h>
+#include <linux/elfnote.h>
+
+ELFNOTE_START(Linux, 0, "a")
+ .long LINUX_VERSION_CODE
+ELFNOTE_END
diff --git a/arch/s390/kernel/vdso64/vdso64.lds.S b/arch/s390/kernel/vdso64/vdso64.lds.S
new file mode 100644
index 000000000..7ddb116b5
--- /dev/null
+++ b/arch/s390/kernel/vdso64/vdso64.lds.S
@@ -0,0 +1,142 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * This is the infamous ld script for the 64 bits vdso
+ * library
+ */
+
+#include <asm/page.h>
+#include <asm/vdso.h>
+
+OUTPUT_FORMAT("elf64-s390", "elf64-s390", "elf64-s390")
+OUTPUT_ARCH(s390:64-bit)
+ENTRY(_start)
+
+SECTIONS
+{
+ . = VDSO64_LBASE + SIZEOF_HEADERS;
+
+ .hash : { *(.hash) } :text
+ .gnu.hash : { *(.gnu.hash) }
+ .dynsym : { *(.dynsym) }
+ .dynstr : { *(.dynstr) }
+ .gnu.version : { *(.gnu.version) }
+ .gnu.version_d : { *(.gnu.version_d) }
+ .gnu.version_r : { *(.gnu.version_r) }
+
+ .note : { *(.note.*) } :text :note
+
+ . = ALIGN(16);
+ .text : {
+ *(.text .stub .text.* .gnu.linkonce.t.*)
+ } :text
+ PROVIDE(__etext = .);
+ PROVIDE(_etext = .);
+ PROVIDE(etext = .);
+
+ /*
+ * Other stuff is appended to the text segment:
+ */
+ .rodata : { *(.rodata .rodata.* .gnu.linkonce.r.*) }
+ .rodata1 : { *(.rodata1) }
+
+ .dynamic : { *(.dynamic) } :text :dynamic
+
+ .eh_frame_hdr : { *(.eh_frame_hdr) } :text :eh_frame_hdr
+ .eh_frame : { KEEP (*(.eh_frame)) } :text
+ .gcc_except_table : { *(.gcc_except_table .gcc_except_table.*) }
+
+ .rela.dyn ALIGN(8) : { *(.rela.dyn) }
+ .got ALIGN(8) : { *(.got .toc) }
+
+ _end = .;
+ PROVIDE(end = .);
+
+ /*
+ * Stabs debugging sections are here too.
+ */
+ .stab 0 : { *(.stab) }
+ .stabstr 0 : { *(.stabstr) }
+ .stab.excl 0 : { *(.stab.excl) }
+ .stab.exclstr 0 : { *(.stab.exclstr) }
+ .stab.index 0 : { *(.stab.index) }
+ .stab.indexstr 0 : { *(.stab.indexstr) }
+ .comment 0 : { *(.comment) }
+
+ /*
+ * DWARF debug sections.
+ * Symbols in the DWARF debugging sections are relative to the
+ * beginning of the section so we begin them at 0.
+ */
+ /* DWARF 1 */
+ .debug 0 : { *(.debug) }
+ .line 0 : { *(.line) }
+ /* GNU DWARF 1 extensions */
+ .debug_srcinfo 0 : { *(.debug_srcinfo) }
+ .debug_sfnames 0 : { *(.debug_sfnames) }
+ /* DWARF 1.1 and DWARF 2 */
+ .debug_aranges 0 : { *(.debug_aranges) }
+ .debug_pubnames 0 : { *(.debug_pubnames) }
+ /* DWARF 2 */
+ .debug_info 0 : { *(.debug_info .gnu.linkonce.wi.*) }
+ .debug_abbrev 0 : { *(.debug_abbrev) }
+ .debug_line 0 : { *(.debug_line) }
+ .debug_frame 0 : { *(.debug_frame) }
+ .debug_str 0 : { *(.debug_str) }
+ .debug_loc 0 : { *(.debug_loc) }
+ .debug_macinfo 0 : { *(.debug_macinfo) }
+ /* SGI/MIPS DWARF 2 extensions */
+ .debug_weaknames 0 : { *(.debug_weaknames) }
+ .debug_funcnames 0 : { *(.debug_funcnames) }
+ .debug_typenames 0 : { *(.debug_typenames) }
+ .debug_varnames 0 : { *(.debug_varnames) }
+ /* DWARF 3 */
+ .debug_pubtypes 0 : { *(.debug_pubtypes) }
+ .debug_ranges 0 : { *(.debug_ranges) }
+ .gnu.attributes 0 : { KEEP (*(.gnu.attributes)) }
+
+ . = ALIGN(PAGE_SIZE);
+ PROVIDE(_vdso_data = .);
+
+ /DISCARD/ : {
+ *(.note.GNU-stack)
+ *(.branch_lt)
+ *(.data .data.* .gnu.linkonce.d.* .sdata*)
+ *(.bss .sbss .dynbss .dynsbss)
+ }
+}
+
+/*
+ * Very old versions of ld do not recognize this name token; use the constant.
+ */
+#define PT_GNU_EH_FRAME 0x6474e550
+
+/*
+ * We must supply the ELF program headers explicitly to get just one
+ * PT_LOAD segment, and set the flags explicitly to make segments read-only.
+ */
+PHDRS
+{
+ text PT_LOAD FILEHDR PHDRS FLAGS(5); /* PF_R|PF_X */
+ dynamic PT_DYNAMIC FLAGS(4); /* PF_R */
+ note PT_NOTE FLAGS(4); /* PF_R */
+ eh_frame_hdr PT_GNU_EH_FRAME;
+}
+
+/*
+ * This controls what symbols we export from the DSO.
+ */
+VERSION
+{
+ VDSO_VERSION_STRING {
+ global:
+ /*
+ * Has to be there for the kernel to find
+ */
+ __kernel_gettimeofday;
+ __kernel_clock_gettime;
+ __kernel_clock_getres;
+ __kernel_getcpu;
+
+ local: *;
+ };
+}
diff --git a/arch/s390/kernel/vdso64/vdso64_generic.c b/arch/s390/kernel/vdso64/vdso64_generic.c
new file mode 100644
index 000000000..a8cef7e4d
--- /dev/null
+++ b/arch/s390/kernel/vdso64/vdso64_generic.c
@@ -0,0 +1,18 @@
+// SPDX-License-Identifier: GPL-2.0
+#include "../../../../lib/vdso/gettimeofday.c"
+
+int __s390_vdso_gettimeofday(struct __kernel_old_timeval *tv,
+ struct timezone *tz)
+{
+ return __cvdso_gettimeofday(tv, tz);
+}
+
+int __s390_vdso_clock_gettime(clockid_t clock, struct __kernel_timespec *ts)
+{
+ return __cvdso_clock_gettime(clock, ts);
+}
+
+int __s390_vdso_clock_getres(clockid_t clock, struct __kernel_timespec *ts)
+{
+ return __cvdso_clock_getres(clock, ts);
+}
diff --git a/arch/s390/kernel/vdso64/vdso64_wrapper.S b/arch/s390/kernel/vdso64/vdso64_wrapper.S
new file mode 100644
index 000000000..672184998
--- /dev/null
+++ b/arch/s390/kernel/vdso64/vdso64_wrapper.S
@@ -0,0 +1,15 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#include <linux/init.h>
+#include <linux/linkage.h>
+#include <asm/page.h>
+
+ __PAGE_ALIGNED_DATA
+
+ .globl vdso64_start, vdso64_end
+ .balign PAGE_SIZE
+vdso64_start:
+ .incbin "arch/s390/kernel/vdso64/vdso64.so"
+ .balign PAGE_SIZE
+vdso64_end:
+
+ .previous
diff --git a/arch/s390/kernel/vdso64/vdso_user_wrapper.S b/arch/s390/kernel/vdso64/vdso_user_wrapper.S
new file mode 100644
index 000000000..a775d7e52
--- /dev/null
+++ b/arch/s390/kernel/vdso64/vdso_user_wrapper.S
@@ -0,0 +1,38 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#include <asm/vdso.h>
+#include <asm/unistd.h>
+#include <asm/asm-offsets.h>
+#include <asm/dwarf.h>
+#include <asm/ptrace.h>
+
+#define WRAPPER_FRAME_SIZE (STACK_FRAME_OVERHEAD+8)
+
+/*
+ * Older glibc version called vdso without allocating a stackframe. This wrapper
+ * is just used to allocate a stackframe. See
+ * https://sourceware.org/git/?p=glibc.git;a=commit;h=478593e6374f3818da39332260dc453cb19cfa1e
+ * for details.
+ */
+.macro vdso_func func
+ .globl __kernel_\func
+ .type __kernel_\func,@function
+ .align 8
+__kernel_\func:
+ CFI_STARTPROC
+ aghi %r15,-WRAPPER_FRAME_SIZE
+ CFI_DEF_CFA_OFFSET (STACK_FRAME_OVERHEAD + WRAPPER_FRAME_SIZE)
+ CFI_VAL_OFFSET 15, -STACK_FRAME_OVERHEAD
+ stg %r14,STACK_FRAME_OVERHEAD(%r15)
+ brasl %r14,__s390_vdso_\func
+ lg %r14,STACK_FRAME_OVERHEAD(%r15)
+ aghi %r15,WRAPPER_FRAME_SIZE
+ CFI_DEF_CFA_OFFSET STACK_FRAME_OVERHEAD
+ CFI_RESTORE 15
+ br %r14
+ CFI_ENDPROC
+ .size __kernel_\func,.-__kernel_\func
+.endm
+
+vdso_func gettimeofday
+vdso_func clock_getres
+vdso_func clock_gettime