From d27f0e5d889f4bf4a796fe2a883b2f264bf40c12 Mon Sep 17 00:00:00 2001 From: Richard Earnshaw Date: Mon, 21 Dec 2020 15:03:03 +0000 Subject: [PATCH] aarch64: Add aarch64-specific files for memory tagging support This final patch provides the architecture-specific implementation of the memory-tagging support hooks for aarch64. --- sysdeps/aarch64/Makefile | 5 +++ sysdeps/aarch64/__mtag_address_get_tag.S | 32 +++++++++++++ sysdeps/aarch64/__mtag_memset_tag.S | 53 ++++++++++++++++++++++ sysdeps/aarch64/__mtag_new_tag.S | 37 +++++++++++++++ sysdeps/aarch64/__mtag_tag_region.S | 51 +++++++++++++++++++++ sysdeps/aarch64/libc-mtag.h | 57 ++++++++++++++++++++++++ 6 files changed, 235 insertions(+) create mode 100644 sysdeps/aarch64/__mtag_address_get_tag.S create mode 100644 sysdeps/aarch64/__mtag_memset_tag.S create mode 100644 sysdeps/aarch64/__mtag_new_tag.S create mode 100644 sysdeps/aarch64/__mtag_tag_region.S create mode 100644 sysdeps/aarch64/libc-mtag.h diff --git a/sysdeps/aarch64/Makefile b/sysdeps/aarch64/Makefile index d8e06d27b2..d3ab37a40a 100644 --- a/sysdeps/aarch64/Makefile +++ b/sysdeps/aarch64/Makefile @@ -40,4 +40,9 @@ endif ifeq ($(subdir),misc) sysdep_headers += sys/ifunc.h +sysdep_routines += __mtag_address_get_tag \ + __mtag_memset_tag \ + __mtag_new_tag \ + __mtag_tag_region + endif diff --git a/sysdeps/aarch64/__mtag_address_get_tag.S b/sysdeps/aarch64/__mtag_address_get_tag.S new file mode 100644 index 0000000000..4ffe884c95 --- /dev/null +++ b/sysdeps/aarch64/__mtag_address_get_tag.S @@ -0,0 +1,32 @@ +/* Copyright (C) 2020 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 + . */ + +#include + +#ifdef USE_MTAG +#define ptr x0 + + .arch armv8.5-a + .arch_extension memtag + +ENTRY (__libc_mtag_address_get_tag) + + ldg ptr, [ptr] + ret +END (__libc_mtag_address_get_tag) +#endif /* USE_MTAG */ diff --git a/sysdeps/aarch64/__mtag_memset_tag.S b/sysdeps/aarch64/__mtag_memset_tag.S new file mode 100644 index 0000000000..6f78d91b79 --- /dev/null +++ b/sysdeps/aarch64/__mtag_memset_tag.S @@ -0,0 +1,53 @@ +/* Copyright (C) 2020 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 + . */ + +#include + +#ifdef USE_MTAG + +/* Use the same register names and assignments as memset. */ +#include "memset-reg.h" + + .arch armv8.5-a + .arch_extension memtag + +/* NB, only supported on variants with 64-bit pointers. */ + +/* FIXME: This is a minimal implementation. We could do much better than + this for large values of COUNT. */ + +ENTRY(__libc_mtag_memset_with_tag) + + and valw, valw, 255 + orr valw, valw, valw, lsl 8 + orr valw, valw, valw, lsl 16 + orr val, val, val, lsl 32 + mov dst, dstin + +L(loop): + stgp val, val, [dst], #16 + subs count, count, 16 + bne L(loop) +#if 0 + /* This is not currently needed, since for now we are only called + to tag memory that is taggable. */ + ldg dstin, [dstin] // Recover the tag created (might be untagged). +#endif + ret +END (__libc_mtag_memset_with_tag) +#endif /* USE_MTAG */ diff --git a/sysdeps/aarch64/__mtag_new_tag.S b/sysdeps/aarch64/__mtag_new_tag.S new file mode 100644 index 0000000000..663e3a484f --- /dev/null +++ b/sysdeps/aarch64/__mtag_new_tag.S @@ -0,0 +1,37 @@ +/* Copyright (C) 2020 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 + . */ + +#include + +#ifdef USE_MTAG + + .arch armv8.5-a + .arch_extension memtag + +/* NB, only supported on variants with 64-bit pointers. */ + +#define ptr x0 +#define xset x1 + +ENTRY(__libc_mtag_new_tag) + // Guarantee that the new tag is not the same as now. + gmi xset, ptr, xzr + irg ptr, ptr, xset + ret +END (__libc_mtag_new_tag) +#endif /* USE_MTAG */ diff --git a/sysdeps/aarch64/__mtag_tag_region.S b/sysdeps/aarch64/__mtag_tag_region.S new file mode 100644 index 0000000000..7af4f0fa0a --- /dev/null +++ b/sysdeps/aarch64/__mtag_tag_region.S @@ -0,0 +1,51 @@ +/* Copyright (C) 2020 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 + . */ + +#include + +#ifdef USE_MTAG + +/* Use the same register names and assignments as memset. */ + + .arch armv8.5-a + .arch_extension memtag + +/* NB, only supported on variants with 64-bit pointers. */ + +/* FIXME: This is a minimal implementation. We could do better than + this for larger values of COUNT. */ + +#define dstin x0 +#define count x1 +#define dst x2 + +ENTRY_ALIGN(__libc_mtag_tag_region, 6) + + mov dst, dstin +L(loop): + stg dst, [dst], #16 + subs count, count, 16 + bne L(loop) +#if 0 + /* This is not currently needed, since for now we are only called + to tag memory that is taggable. */ + ldg dstin, [dstin] // Recover the tag created (might be untagged). +#endif + ret +END (__libc_mtag_tag_region) +#endif /* USE_MTAG */ diff --git a/sysdeps/aarch64/libc-mtag.h b/sysdeps/aarch64/libc-mtag.h new file mode 100644 index 0000000000..a60c623777 --- /dev/null +++ b/sysdeps/aarch64/libc-mtag.h @@ -0,0 +1,57 @@ +/* libc-internal interface for tagged (colored) memory support. + Copyright (C) 2020 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 + . */ + +#ifndef _AARCH64_LIBC_MTAG_H +#define _AARCH64_LIBC_MTAG_H 1 + +#ifndef USE_MTAG +/* Generic bindings for systems that do not support memory tagging. */ +#include_next "libc-mtag.h" +#else + +/* Used to ensure additional alignment when objects need to have distinct + tags. */ +#define __MTAG_GRANULE_SIZE 16 + +/* Non-zero if memory obtained via morecore (sbrk) is not tagged. */ +#define __MTAG_SBRK_UNTAGGED 1 + +/* Extra flags to pass to mmap to get tagged pages. */ +#define __MTAG_MMAP_FLAGS PROT_MTE + +/* Set the tags for a region of memory, which must have size and alignment + that are multiples of __MTAG_GRANULE_SIZE. Size cannot be zero. + void *__libc_mtag_tag_region (const void *, size_t) */ +void *__libc_mtag_tag_region (void *, size_t); + +/* Optimized equivalent to __libc_mtag_tag_region followed by memset. */ +void *__libc_mtag_memset_with_tag (void *, int, size_t); + +/* Convert address P to a pointer that is tagged correctly for that + location. + void *__libc_mtag_address_get_tag (void*) */ +void *__libc_mtag_address_get_tag (void *); + +/* Assign a new (random) tag to a pointer P (does not adjust the tag on + the memory addressed). + void *__libc_mtag_new_tag (void*) */ +void *__libc_mtag_new_tag (void *); + +#endif /* USE_MTAG */ + +#endif /* _AARCH64_LIBC_MTAG_H */