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

[Alexander Graf]

On 10.12.2012, at 11:27, Cornelia Huck wrote:

> On Mon, 10 Dec 2012 09:20:57 +0100
> Alexander Graf <address@hidden> wrote:
> 
>> 
>> 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) :).
> 
> Yes, since do_ext_interrupt which I copy/pasted this from does as
> well :) Will add.

Oops :). Patches welcome!

> 
>> 
>>> +
>>> +        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?
> 
> Something that should be MCHK_TYPE_CRW or so :)

Sounds like a great name for a 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 :)
> 
> OK
> 
>> 
>>> +        /* CRW machine checks disabled */
>>> +        return;
>>> +    }
>>> +
>>> +    lowcore = cpu_physical_memory_map(env->psa, &len, 1);
>> 
>> Check missing again.
> 
> Perhaps we want {map,unmap}_lowcore() functions?

Awesome idea!


Alex