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author | Michael Ellerman <mpe@ellerman.id.au> | 2014-09-25 16:45:11 +1000 |
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committer | Michael Ellerman <mpe@ellerman.id.au> | 2014-09-30 14:59:12 +1000 |
commit | fe2a1bb1dbff1bc7b8c24eb1f691a544488617fa (patch) | |
tree | a224f729189b0cb116be365eb13235de8679be57 /tools/testing/selftests/powerpc/primitives/load_unaligned_zeropad.c | |
parent | de5946c03575fb8c222610a6ac6726a5deabad46 (diff) | |
download | op-kernel-dev-fe2a1bb1dbff1bc7b8c24eb1f691a544488617fa.zip op-kernel-dev-fe2a1bb1dbff1bc7b8c24eb1f691a544488617fa.tar.gz |
selftests/powerpc: Add test of load_unaligned_zero_pad()
It is a rarely exercised case, so we want to have a test to ensure it
works as required.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Diffstat (limited to 'tools/testing/selftests/powerpc/primitives/load_unaligned_zeropad.c')
-rw-r--r-- | tools/testing/selftests/powerpc/primitives/load_unaligned_zeropad.c | 147 |
1 files changed, 147 insertions, 0 deletions
diff --git a/tools/testing/selftests/powerpc/primitives/load_unaligned_zeropad.c b/tools/testing/selftests/powerpc/primitives/load_unaligned_zeropad.c new file mode 100644 index 0000000..d1b6475 --- /dev/null +++ b/tools/testing/selftests/powerpc/primitives/load_unaligned_zeropad.c @@ -0,0 +1,147 @@ +/* + * Userspace test harness for load_unaligned_zeropad. Creates two + * pages and uses mprotect to prevent access to the second page and + * a SEGV handler that walks the exception tables and runs the fixup + * routine. + * + * The results are compared against a normal load that is that is + * performed while access to the second page is enabled via mprotect. + * + * Copyright (C) 2014 Anton Blanchard <anton@au.ibm.com>, IBM + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version + * 2 of the License, or (at your option) any later version. + */ + +#include <stdlib.h> +#include <string.h> +#include <stdio.h> +#include <stdbool.h> +#include <signal.h> +#include <unistd.h> +#include <sys/mman.h> + +#define FIXUP_SECTION ".ex_fixup" + +#include "word-at-a-time.h" + +#include "utils.h" + + +static int page_size; +static char *mem_region; + +static int protect_region(void) +{ + if (mprotect(mem_region + page_size, page_size, PROT_NONE)) { + perror("mprotect"); + return 1; + } + + return 0; +} + +static int unprotect_region(void) +{ + if (mprotect(mem_region + page_size, page_size, PROT_READ|PROT_WRITE)) { + perror("mprotect"); + return 1; + } + + return 0; +} + +extern char __start___ex_table[]; +extern char __stop___ex_table[]; + +#if defined(__powerpc64__) +#define UCONTEXT_NIA(UC) (UC)->uc_mcontext.gp_regs[PT_NIP] +#elif defined(__powerpc__) +#define UCONTEXT_NIA(UC) (UC)->uc_mcontext.uc_regs->gregs[PT_NIP] +#else +#error implement UCONTEXT_NIA +#endif + +static int segv_error; + +static void segv_handler(int signr, siginfo_t *info, void *ptr) +{ + ucontext_t *uc = (ucontext_t *)ptr; + unsigned long addr = (unsigned long)info->si_addr; + unsigned long *ip = &UCONTEXT_NIA(uc); + unsigned long *ex_p = (unsigned long *)__start___ex_table; + + while (ex_p < (unsigned long *)__stop___ex_table) { + unsigned long insn, fixup; + + insn = *ex_p++; + fixup = *ex_p++; + + if (insn == *ip) { + *ip = fixup; + return; + } + } + + printf("No exception table match for NIA %lx ADDR %lx\n", *ip, addr); + segv_error++; +} + +static void setup_segv_handler(void) +{ + struct sigaction action; + + memset(&action, 0, sizeof(action)); + action.sa_sigaction = segv_handler; + action.sa_flags = SA_SIGINFO; + sigaction(SIGSEGV, &action, NULL); +} + +static int do_one_test(char *p, int page_offset) +{ + unsigned long should; + unsigned long got; + + FAIL_IF(unprotect_region()); + should = *(unsigned long *)p; + FAIL_IF(protect_region()); + + got = load_unaligned_zeropad(p); + + if (should != got) + printf("offset %u load_unaligned_zeropad returned 0x%lx, should be 0x%lx\n", page_offset, got, should); + + return 0; +} + +static int test_body(void) +{ + unsigned long i; + + page_size = getpagesize(); + mem_region = mmap(NULL, page_size * 2, PROT_READ|PROT_WRITE, + MAP_PRIVATE|MAP_ANONYMOUS, -1, 0); + + FAIL_IF(mem_region == MAP_FAILED); + + for (i = 0; i < page_size; i++) + mem_region[i] = i; + + memset(mem_region+page_size, 0, page_size); + + setup_segv_handler(); + + for (i = 0; i < page_size; i++) + FAIL_IF(do_one_test(mem_region+i, i)); + + FAIL_IF(segv_error); + + return 0; +} + +int main(void) +{ + return test_harness(test_body, "load_unaligned_zeropad"); +} |