Re: [Qemu-devel] [PATCH 3/8] s390: I/O interrupt and machine check injection.

[Alexander Graf]

On 07.12.2012, at 13:50, Cornelia Huck wrote:

> I/O interrupts are queued per isc. Only crw pending machine checks
> are supported.
> 
> Signed-off-by: Cornelia Huck <address@hidden>
> ---
> target-s390x/cpu.h    |  67 +++++++++++++++++++++++
> target-s390x/helper.c | 145 ++++++++++++++++++++++++++++++++++++++++++++++++++
> 2 files changed, 212 insertions(+)
> 
> diff --git a/target-s390x/cpu.h b/target-s390x/cpu.h
> index 0f9a1f7..73bfc20 100644
> --- a/target-s390x/cpu.h
> +++ b/target-s390x/cpu.h
> @@ -47,6 +47,11 @@
> #define MMU_USER_IDX 1
> 
> #define MAX_EXT_QUEUE 16
> +#define MAX_IO_QUEUE 16
> +#define MAX_MCHK_QUEUE 16
> +
> +#define PSW_MCHK_MASK 0x0004000000000000
> +#define PSW_IO_MASK 0x0200000000000000
> 
> typedef struct PSW {
>     uint64_t mask;
> @@ -59,6 +64,17 @@ typedef struct ExtQueue {
>     uint32_t param64;
> } ExtQueue;
> 
> +typedef struct IOQueue {
> +    uint16_t id;
> +    uint16_t nr;
> +    uint32_t parm;
> +    uint32_t word;
> +} IOQueue;
> +
> +typedef struct MchkQueue {
> +    uint16_t type;
> +} MchkQueue;
> +
> typedef struct CPUS390XState {
>     uint64_t regs[16];        /* GP registers */
> 
> @@ -88,8 +104,16 @@ typedef struct CPUS390XState {
> 
>     int pending_int;
>     ExtQueue ext_queue[MAX_EXT_QUEUE];
> +    IOQueue io_queue[MAX_IO_QUEUE][8];
> +    MchkQueue mchk_queue[MAX_MCHK_QUEUE];
> 
>     int ext_index;
> +    int io_index[8];
> +    int mchk_index;
> +
> +    uint64_t ckc;
> +    uint64_t cputm;
> +    uint32_t todpr;
> 
>     CPU_COMMON
> 
> @@ -364,12 +388,16 @@ static inline void cpu_set_tls(CPUS390XState *env, 
> target_ulong newtls)
> #define EXCP_EXT 1 /* external interrupt */
> #define EXCP_SVC 2 /* supervisor call (syscall) */
> #define EXCP_PGM 3 /* program interruption */
> +#define EXCP_IO  7 /* I/O interrupt */
> +#define EXCP_MCHK 8 /* machine check */
> 
> #endif /* CONFIG_USER_ONLY */
> 
> #define INTERRUPT_EXT        (1 << 0)
> #define INTERRUPT_TOD        (1 << 1)
> #define INTERRUPT_CPUTIMER   (1 << 2)
> +#define INTERRUPT_IO         (1 << 3)
> +#define INTERRUPT_MCHK       (1 << 4)
> 
> /* Program Status Word.  */
> #define S390_PSWM_REGNUM 0
> @@ -977,6 +1005,45 @@ static inline void cpu_inject_ext(CPUS390XState *env, 
> uint32_t code, uint32_t pa
>     cpu_interrupt(env, CPU_INTERRUPT_HARD);
> }
> 
> +static inline void cpu_inject_io(CPUS390XState *env, uint16_t subchannel_id,
> +                                 uint16_t subchannel_number,
> +                                 uint32_t io_int_parm, uint32_t io_int_word)
> +{
> +    int isc = ffs(io_int_word << 2) - 1;
> +
> +    if (env->io_index[isc] == MAX_IO_QUEUE - 1) {
> +        /* ugh - can't queue anymore. Let's drop. */
> +        return;
> +    }
> +
> +    env->io_index[isc]++;
> +    assert(env->io_index[isc] < MAX_IO_QUEUE);
> +
> +    env->io_queue[env->io_index[isc]][isc].id = subchannel_id;
> +    env->io_queue[env->io_index[isc]][isc].nr = subchannel_number;
> +    env->io_queue[env->io_index[isc]][isc].parm = io_int_parm;
> +    env->io_queue[env->io_index[isc]][isc].word = io_int_word;
> +
> +    env->pending_int |= INTERRUPT_IO;
> +    cpu_interrupt(env, CPU_INTERRUPT_HARD);
> +}
> +
> +static inline void cpu_inject_crw_mchk(CPUS390XState *env)
> +{
> +    if (env->mchk_index == MAX_MCHK_QUEUE - 1) {
> +        /* ugh - can't queue anymore. Let's drop. */
> +        return;
> +    }
> +
> +    env->mchk_index++;
> +    assert(env->mchk_index < MAX_MCHK_QUEUE);
> +
> +    env->mchk_queue[env->mchk_index].type = 1;
> +
> +    env->pending_int |= INTERRUPT_MCHK;
> +    cpu_interrupt(env, CPU_INTERRUPT_HARD);
> +}
> +
> static inline bool cpu_has_work(CPUState *cpu)
> {
>     CPUS390XState *env = &S390_CPU(cpu)->env;
> diff --git a/target-s390x/helper.c b/target-s390x/helper.c
> index b7b812a..4ff148d 100644
> --- a/target-s390x/helper.c
> +++ b/target-s390x/helper.c
> @@ -574,12 +574,144 @@ static void do_ext_interrupt(CPUS390XState *env)
>     load_psw(env, mask, addr);
> }
> 
> +static void do_io_interrupt(CPUS390XState *env)
> +{
> +    uint64_t mask, addr;
> +    LowCore *lowcore;
> +    hwaddr len = TARGET_PAGE_SIZE;
> +    IOQueue *q;
> +    uint8_t isc;
> +    int disable = 1;
> +    int found = 0;
> +
> +    if (!(env->psw.mask & PSW_MASK_IO)) {
> +        cpu_abort(env, "I/O int w/o I/O mask\n");
> +    }
> +
> +    for (isc = 0; isc < 8; isc++) {
> +        if (env->io_index[isc] < 0) {
> +            continue;
> +        }
> +        if (env->io_index[isc] > MAX_IO_QUEUE) {
> +            cpu_abort(env, "I/O queue overrun for isc %d: %d\n",
> +                      isc, env->io_index[isc]);
> +        }
> +
> +        q = &env->io_queue[env->io_index[isc]][isc];
> +        if (!(env->cregs[6] & q->word)) {
> +            disable = 0;
> +            continue;
> +        }
> +        found = 1;
> +        lowcore = cpu_physical_memory_map(env->psa, &len, 1);

This one is missing a check whether len >= sizeof(*lowcore) :).

> +
> +        lowcore->subchannel_id = cpu_to_be16(q->id);
> +        lowcore->subchannel_nr = cpu_to_be16(q->nr);
> +        lowcore->io_int_parm = cpu_to_be32(q->parm);
> +        lowcore->io_int_word = cpu_to_be32(q->word);
> +        lowcore->io_old_psw.mask = cpu_to_be64(get_psw_mask(env));
> +        lowcore->io_old_psw.addr = cpu_to_be64(env->psw.addr);
> +        mask = be64_to_cpu(lowcore->io_new_psw.mask);
> +        addr = be64_to_cpu(lowcore->io_new_psw.addr);
> +
> +        cpu_physical_memory_unmap(lowcore, len, 1, len);
> +
> +        env->io_index[isc]--;
> +        if (env->io_index >= 0) {
> +            disable = 0;
> +        }
> +        break;
> +    }
> +
> +    if (disable) {
> +        env->pending_int &= ~INTERRUPT_IO;
> +    }
> +
> +    if (found) {
> +        DPRINTF("%s: %" PRIx64 " %" PRIx64 "\n", __func__,
> +                env->psw.mask, env->psw.addr);
> +        load_psw(env, mask, addr);
> +    }
> +}
> +
> +static void do_mchk_interrupt(CPUS390XState *env)
> +{
> +    uint64_t mask, addr;
> +    LowCore *lowcore;
> +    hwaddr len = TARGET_PAGE_SIZE;
> +    MchkQueue *q;
> +    int i;
> +
> +    if (!(env->psw.mask & PSW_MASK_MCHECK)) {
> +        cpu_abort(env, "Machine check w/o mchk mask\n");
> +    }
> +
> +    if (env->mchk_index < 0 || env->mchk_index > MAX_MCHK_QUEUE) {
> +        cpu_abort(env, "Mchk queue overrun: %d\n", env->mchk_index);
> +    }
> +
> +    q = &env->mchk_queue[env->mchk_index];
> +
> +    if (q->type != 1) {

What is type 1?

> +        /* Don't know how to handle this... */
> +        cpu_abort(env, "Unknown machine check type %d\n", q->type);
> +    }
> +    if (!(env->cregs[14] & (1 << 28))) {

Please create a #define for this one :)

> +        /* CRW machine checks disabled */
> +        return;
> +    }
> +
> +    lowcore = cpu_physical_memory_map(env->psa, &len, 1);

Check missing again.

> +
> +    for (i = 0; i < 16; i++) {
> +        lowcore->floating_pt_save_area[i] = cpu_to_be64(env->fregs[i].ll);
> +        lowcore->gpregs_save_area[i] = cpu_to_be64(env->regs[i]);
> +        lowcore->access_regs_save_area[i] = cpu_to_be32(env->aregs[i]);
> +        lowcore->cregs_save_area[i] = cpu_to_be64(env->cregs[i]);
> +    }
> +    lowcore->prefixreg_save_area = cpu_to_be32(env->psa);
> +    lowcore->fpt_creg_save_area = cpu_to_be32(env->fpc);
> +    lowcore->tod_progreg_save_area = cpu_to_be32(env->todpr);
> +    lowcore->cpu_timer_save_area[0] = cpu_to_be32(env->cputm >> 32);
> +    lowcore->cpu_timer_save_area[1] =
> +        cpu_to_be32(env->cputm & 0x00000000ffffffff);

cpu_to_be32((uint32_t)env->cputm)

> +    lowcore->clock_comp_save_area[0] = cpu_to_be32(env->ckc >> 32);
> +    lowcore->clock_comp_save_area[1] =
> +        cpu_to_be32(env->ckc & 0x00000000ffffffff);
> +
> +    lowcore->mcck_interruption_code[0] = cpu_to_be32(0x00400f1d);
> +    lowcore->mcck_interruption_code[1] = cpu_to_be32(0x40330000);
> +    lowcore->mcck_old_psw.mask = cpu_to_be64(get_psw_mask(env));
> +    lowcore->mcck_old_psw.addr = cpu_to_be64(env->psw.addr);
> +    mask = be64_to_cpu(lowcore->mcck_new_psw.mask);
> +    addr = be64_to_cpu(lowcore->mcck_new_psw.addr);
> +
> +    cpu_physical_memory_unmap(lowcore, len, 1, len);
> +
> +    env->mchk_index--;
> +    if (env->mchk_index == -1) {
> +        env->pending_int &= ~INTERRUPT_MCHK;
> +    }
> +
> +    DPRINTF("%s: %" PRIx64 " %" PRIx64 "\n", __func__,
> +            env->psw.mask, env->psw.addr);
> +
> +    load_psw(env, mask, addr);
> +}
> +
> void do_interrupt(CPUS390XState *env)
> {
>     qemu_log_mask(CPU_LOG_INT, "%s: %d at pc=%" PRIx64 "\n",
>                   __func__, env->exception_index, env->psw.addr);
> 
>     s390_add_running_cpu(env);
> +    /* handle machine checks */
> +    if ((env->psw.mask & PSW_MASK_MCHECK) &&
> +        (env->exception_index == -1)) {
> +        if (env->pending_int & INTERRUPT_MCHK) {
> +            env->exception_index = EXCP_MCHK;
> +        }
> +    }
>     /* handle external interrupts */
>     if ((env->psw.mask & PSW_MASK_EXT) &&
>         env->exception_index == -1) {
> @@ -598,6 +730,13 @@ void do_interrupt(CPUS390XState *env)
>             env->pending_int &= ~INTERRUPT_TOD;
>         }
>     }
> +    /* handle I/O interrupts */
> +    if ((env->psw.mask & PSW_MASK_IO) &&
> +        (env->exception_index == -1)) {
> +        if (env->pending_int & INTERRUPT_IO) {
> +            env->exception_index = EXCP_IO;
> +        }
> +    }
> 
>     switch (env->exception_index) {
>     case EXCP_PGM:
> @@ -609,6 +748,12 @@ void do_interrupt(CPUS390XState *env)
>     case EXCP_EXT:
>         do_ext_interrupt(env);
>         break;
> +    case EXCP_IO:
> +        do_io_interrupt(env);
> +        break;
> +    case EXCP_MCHK:
> +        do_mchk_interrupt(env);
> +        break;
>     }
>     env->exception_index = -1;
> 
> -- 
> 1.7.12.4
>