// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Ptrace test TM SPR registers
 *
 * Copyright (C) 2015 Anshuman Khandual, IBM Corporation.
 */
#include "ptrace.h"
#include "tm.h"

/* Tracee and tracer shared data */
struct shared {
        int flag;
        struct tm_spr_regs regs;
};
unsigned long tfhar;

int shm_id;
struct shared *cptr, *pptr;

int shm_id1;
int *cptr1, *pptr1;

#define TM_KVM_SCHED   0xe0000001ac000001
int validate_tm_spr(struct tm_spr_regs *regs)
{
        FAIL_IF(regs->tm_tfhar != tfhar);
        FAIL_IF((regs->tm_texasr == TM_KVM_SCHED) && (regs->tm_tfiar != 0));

        return TEST_PASS;
}

void tm_spr(void)
{
        unsigned long result, texasr;
        int ret;

        cptr = (struct shared *)shmat(shm_id, NULL, 0);
        cptr1 = (int *)shmat(shm_id1, NULL, 0);

trans:
        cptr1[0] = 0;
        asm __volatile__(
                "1: ;"
                /* TM failover handler should follow "tbegin.;" */
                "mflr 31;"
                "bl 4f;"        /* $ = TFHAR - 12 */
                "4: ;"
                "mflr %[tfhar];"
                "mtlr 31;"

                "tbegin.;"
                "beq 2f;"

                "tsuspend.;"
                "li 8, 1;"
                "sth 8, 0(%[cptr1]);"
                "tresume.;"
                "b .;"

                "tend.;"
                "li 0, 0;"
                "ori %[res], 0, 0;"
                "b 3f;"

                "2: ;"

                "li 0, 1;"
                "ori %[res], 0, 0;"
                "mfspr %[texasr], %[sprn_texasr];"

                "3: ;"
                : [tfhar] "=r" (tfhar), [res] "=r" (result),
                [texasr] "=r" (texasr), [cptr1] "=b" (cptr1)
                : [sprn_texasr] "i"  (SPRN_TEXASR)
                : "memory", "r0", "r8", "r31"
                );

        /* There are 2 32bit instructions before tbegin. */
        tfhar += 12;

        if (result) {
                if (!cptr->flag)
                        goto trans;

                ret = validate_tm_spr((struct tm_spr_regs *)&cptr->regs);
                shmdt((void *)cptr);
                shmdt((void *)cptr1);
                if (ret)
                        exit(1);
                exit(0);
        }
        shmdt((void *)cptr);
        shmdt((void *)cptr1);
        exit(1);
}

int trace_tm_spr(pid_t child)
{
        FAIL_IF(start_trace(child));
        FAIL_IF(show_tm_spr(child, (struct tm_spr_regs *)&pptr->regs));

        printf("TFHAR: %lx TEXASR: %lx TFIAR: %lx\n", pptr->regs.tm_tfhar,
                                pptr->regs.tm_texasr, pptr->regs.tm_tfiar);

        pptr->flag = 1;
        FAIL_IF(stop_trace(child));

        return TEST_PASS;
}

int ptrace_tm_spr(void)
{
        pid_t pid;
        int ret, status;

        SKIP_IF_MSG(!have_htm(), "Don't have transactional memory");
        SKIP_IF_MSG(htm_is_synthetic(), "Transactional memory is synthetic");
        shm_id = shmget(IPC_PRIVATE, sizeof(struct shared), 0777|IPC_CREAT);
        shm_id1 = shmget(IPC_PRIVATE, sizeof(int), 0777|IPC_CREAT);
        pid = fork();
        if (pid < 0) {
                perror("fork() failed");
                return TEST_FAIL;
        }

        if (pid == 0)
                tm_spr();

        if (pid) {
                pptr = (struct shared *)shmat(shm_id, NULL, 0);
                pptr1 = (int *)shmat(shm_id1, NULL, 0);

                while (!pptr1[0])
                        asm volatile("" : : : "memory");
                ret = trace_tm_spr(pid);
                if (ret) {
                        kill(pid, SIGKILL);
                        shmdt((void *)pptr);
                        shmdt((void *)pptr1);
                        shmctl(shm_id, IPC_RMID, NULL);
                        shmctl(shm_id1, IPC_RMID, NULL);
                        return TEST_FAIL;
                }

                shmdt((void *)pptr);
                shmdt((void *)pptr1);
                ret = wait(&status);
                shmctl(shm_id, IPC_RMID, NULL);
                shmctl(shm_id1, IPC_RMID, NULL);
                if (ret != pid) {
                        printf("Child's exit status not captured\n");
                        return TEST_FAIL;
                }

                return (WIFEXITED(status) && WEXITSTATUS(status)) ? TEST_FAIL :
                        TEST_PASS;
        }
        return TEST_PASS;
}

int main(int argc, char *argv[])
{
        return test_harness(ptrace_tm_spr, "ptrace_tm_spr");
}