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.
This commit is contained in:
Richard Earnshaw 2020-11-20 17:20:10 +00:00
parent 05ab98edbd
commit 8a9f2a6e9b
6 changed files with 221 additions and 0 deletions

View File

@ -40,4 +40,9 @@ endif
ifeq ($(subdir),misc)
sysdep_headers += sys/ifunc.h
sysdep_routines += __mtag_tag_region __mtag_new_tag __mtag_address_get_tag
endif
ifeq ($(subdir),string)
sysdep_routines += __mtag_memset_tag
endif

View File

@ -0,0 +1,31 @@
/* 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
<http://www.gnu.org/licenses/>. */
#include <sysdep.h>
#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)
libc_hidden_builtin_def (__libc_mtag_address_get_tag)

View File

@ -0,0 +1,46 @@
/* 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
<http://www.gnu.org/licenses/>. */
#include <sysdep.h>
/* 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_ALIGN(__libc_mtag_memset_with_tag, 6)
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)
ldg dstin, [dstin] // Recover the tag created (might be untagged).
ret
END (__libc_mtag_memset_with_tag)
libc_hidden_builtin_def (__libc_mtag_memset_with_tag)

View File

@ -0,0 +1,38 @@
/* 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
<http://www.gnu.org/licenses/>. */
#include <sysdep.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 better than
this for larger values of COUNT. */
#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)
libc_hidden_builtin_def (__libc_mtag_new_tag)

View File

@ -0,0 +1,44 @@
/* 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
<http://www.gnu.org/licenses/>. */
#include <sysdep.h>
/* 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)
ldg dstin, [dstin] // Recover the tag created (might be untagged).
ret
END (__libc_mtag_tag_region)
libc_hidden_builtin_def (__libc_mtag_tag_region)

View File

@ -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
<http://www.gnu.org/licenses/>. */
#ifndef _AARCH64_LIBC_MTAG_H
#define _AARCH64_LIBC_MTAG_H 1
#ifndef _LIBC_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 /* _LIBC_MTAG */
#endif /* _AARCH64_LIBC_MTAG_H */