Re: [PATCH 4/8] s390: Add channel I/O instructions.

[Cornelia Huck <cornelia.huck@de.ibm.com>]

On Mon, 10 Dec 2012 10:00:16 +0100
Alexander Graf <agraf@suse.de> wrote:

> 
> 
> On 07.12.2012, at 13:50, Cornelia Huck <cornelia.huck@de.ibm.com> wrote:
> 
> > Provide handlers for (most) channel I/O instructions.
> > 
> > Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
> > ---
> > target-s390x/cpu.h    |  87 +++++++
> > target-s390x/ioinst.c | 694 +++++++++++++++++++++++++++++++++++++++++++++++++-
> > target-s390x/ioinst.h |  16 ++
> > trace-events          |   6 +
> > 4 files changed, 796 insertions(+), 7 deletions(-)
> > 
> > diff --git a/target-s390x/cpu.h b/target-s390x/cpu.h
> > index 73bfc20..bc119f8 100644
> > --- a/target-s390x/cpu.h
> > +++ b/target-s390x/cpu.h
> > @@ -127,6 +127,8 @@ typedef struct CPUS390XState {
> >     QEMUTimer *tod_timer;
> > 
> >     QEMUTimer *cpu_timer;
> > +
> > +    void *chsc_page;
> > } CPUS390XState;
> > 
> > #include "cpu-qom.h"
> > @@ -363,6 +365,91 @@ static inline unsigned s390_del_running_cpu(CPUS390XState *env)
> > void cpu_lock(void);
> > void cpu_unlock(void);
> > 
> > +typedef struct SubchDev SubchDev;
> > +typedef struct SCHIB SCHIB;
> > +typedef struct ORB ORB;
> > +
> > +static inline SubchDev *css_find_subch(uint8_t m, uint8_t cssid, uint8_t ssid,
> > +                                       uint16_t schid)
> > +{
> > +    return NULL;
> > +}
> > +static inline bool css_subch_visible(SubchDev *sch)
> > +{
> > +    return false;
> > +}
> > +static inline void css_conditional_io_interrupt(SubchDev *sch)
> > +{
> > +}
> > +static inline int css_do_stsch(SubchDev *sch, uint64_t addr)
> > +{
> > +    return -ENODEV;
> > +}
> > +static inline bool css_schid_final(uint8_t cssid, uint8_t ssid, uint16_t schid)
> > +{
> > +    return true;
> > +}
> > +static inline int css_do_msch(SubchDev *sch, SCHIB *schib)
> > +{
> > +    return -ENODEV;
> > +}
> > +static inline int css_do_xsch(SubchDev *sch)
> > +{
> > +    return -ENODEV;
> > +}
> > +static inline int css_do_csch(SubchDev *sch)
> > +{
> > +    return -ENODEV;
> > +}
> > +static inline int css_do_hsch(SubchDev *sch)
> > +{
> > +    return -ENODEV;
> > +}
> > +static inline int css_do_ssch(SubchDev *sch, ORB *orb)
> > +{
> > +    return -ENODEV;
> > +}
> > +static inline int css_do_tsch(SubchDev *sch, uint64_t addr)
> > +{
> > +    return -ENODEV;
> > +}
> > +static inline int css_do_stcrw(uint64_t addr)
> > +{
> > +    return 1;
> > +}
> > +static inline int css_do_tpi(uint64_t addr, int lowcore)
> > +{
> > +    return 0;
> > +}
> > +static inline int css_collect_chp_desc(int m, uint8_t cssid, uint8_t f_chpid,
> > +                                       int rfmt, uint8_t l_chpid, void *buf)
> > +{
> > +    return 0;
> > +}
> > +static inline void css_do_schm(uint8_t mbk, int update, int dct, uint64_t mbo)
> > +{
> > +}
> > +static inline int css_enable_mss(void)
> > +{
> > +    return -EINVAL;
> > +}
> > +static inline int css_enable_mcsse(void)
> > +{
> > +    return -EINVAL;
> > +}
> > +static inline int css_do_rsch(SubchDev *sch)
> > +{
> > +    return -ENODEV;
> > +}
> > +static inline int css_do_rchp(uint8_t cssid, uint8_t chpid)
> > +{
> > +    return -ENODEV;
> > +}
> > +static inline bool css_present(uint8_t cssid)
> > +{
> > +    return false;
> > +}
> > +
> > static inline void cpu_set_tls(CPUS390XState *env, target_ulong newtls)
> > {
> >     env->aregs[0] = newtls >> 32;
> > diff --git a/target-s390x/ioinst.c b/target-s390x/ioinst.c
> > index 8577b2c..60ce985 100644
> > --- a/target-s390x/ioinst.c
> > +++ b/target-s390x/ioinst.c
> > @@ -15,14 +15,19 @@
> > 
> > #include "cpu.h"
> > #include "ioinst.h"
> > +#include "trace.h"
> > 
> > -#ifdef DEBUG_IOINST
> > -#define dprintf(fmt, ...) \
> > -    do { fprintf(stderr, fmt, ## __VA_ARGS__); } while (0)
> > -#else
> > -#define dprintf(fmt, ...) \
> > -    do { } while (0)
> > -#endif
> > +/* Special handling for the prefix page. */
> > +static void *s390_get_address(CPUS390XState *env, ram_addr_t guest_addr)
> > +{
> > +    if (guest_addr < 8192) {
> > +        guest_addr += env->psa;
> > +    } else if ((env->psa <= guest_addr) && (guest_addr < env->psa + 8192)) {
> > +        guest_addr -= env->psa;
> > +    }
> > +
> > +    return qemu_get_ram_ptr(guest_addr);
> 
> Do we actually need this?

Yes. I've seen failures for I/O instructions using the lowcore (which
the Linux kernel likes to do).

> 
> > +}
> > 
> > int ioinst_disassemble_sch_ident(uint32_t value, int *m, int *cssid, int *ssid,
> >                                  int *schid)
> > @@ -44,3 +49,678 @@ int ioinst_disassemble_sch_ident(uint32_t value, int *m, int *cssid, int *ssid,
> >     *schid = value & IOINST_SCHID_NR;
> >     return 0;
> > }
> > +
> > +int ioinst_handle_xsch(CPUS390XState *env, uint64_t reg1)
> > +{
> > +    int cssid, ssid, schid, m;
> > +    SubchDev *sch;
> > +    int ret = -ENODEV;
> > +    int cc;
> > +
> > +    if (ioinst_disassemble_sch_ident(reg1, &m, &cssid, &ssid, &schid)) {
> > +        program_interrupt(env, PGM_OPERAND, 2);
> > +        return -EIO;
> > +    }
> > +    trace_ioinst_sch_id("xsch", cssid, ssid, schid);
> > +    sch = css_find_subch(m, cssid, ssid, schid);
> > +    if (sch && css_subch_visible(sch)) {
> > +        ret = css_do_xsch(sch);
> > +    }
> > +    switch (ret) {
> > +    case -ENODEV:
> > +        cc = 3;
> > +        break;
> > +    case -EBUSY:
> > +        cc = 2;
> > +        break;
> > +    case 0:
> > +        cc = 0;
> > +        break;
> > +    default:
> > +        cc = 1;
> > +        break;
> > +    }
> > +
> > +    return cc;
> > +}
> > +
> > +int ioinst_handle_csch(CPUS390XState *env, uint64_t reg1)
> > +{
> > +    int cssid, ssid, schid, m;
> > +    SubchDev *sch;
> > +    int ret = -ENODEV;
> > +    int cc;
> > +
> > +    if (ioinst_disassemble_sch_ident(reg1, &m, &cssid, &ssid, &schid)) {
> > +        program_interrupt(env, PGM_OPERAND, 2);
> > +        return -EIO;
> > +    }
> > +    trace_ioinst_sch_id("csch", cssid, ssid, schid);
> > +    sch = css_find_subch(m, cssid, ssid, schid);
> > +    if (sch && css_subch_visible(sch)) {
> > +        ret = css_do_csch(sch);
> > +    }
> > +    if (ret == -ENODEV) {
> > +        cc = 3;
> > +    } else {
> > +        cc = 0;
> > +    }
> > +    return cc;
> > +}
> > +
> > +int ioinst_handle_hsch(CPUS390XState *env, uint64_t reg1)
> > +{
> > +    int cssid, ssid, schid, m;
> > +    SubchDev *sch;
> > +    int ret = -ENODEV;
> > +    int cc;
> > +
> > +    if (ioinst_disassemble_sch_ident(reg1, &m, &cssid, &ssid, &schid)) {
> > +        program_interrupt(env, PGM_OPERAND, 2);
> > +        return -EIO;
> > +    }
> > +    trace_ioinst_sch_id("hsch", cssid, ssid, schid);
> > +    sch = css_find_subch(m, cssid, ssid, schid);
> > +    if (sch && css_subch_visible(sch)) {
> > +        ret = css_do_hsch(sch);
> > +    }
> > +    switch (ret) {
> > +    case -ENODEV:
> > +        cc = 3;
> > +        break;
> > +    case -EBUSY:
> > +        cc = 2;
> > +        break;
> > +    case 0:
> > +        cc = 0;
> > +        break;
> > +    default:
> > +        cc = 1;
> > +        break;
> > +    }
> > +
> > +    return cc;
> > +}
> > +
> > +static int ioinst_schib_valid(SCHIB *schib)
> > +{
> > +    if ((schib->pmcw.flags & PMCW_FLAGS_MASK_INVALID) ||
> > +        (schib->pmcw.chars & PMCW_CHARS_MASK_INVALID)) {
> > +        return 0;
> > +    }
> > +    /* Disallow extended measurements for now. */
> > +    if (schib->pmcw.chars & PMCW_CHARS_MASK_XMWME) {
> > +        return 0;
> > +    }
> > +    return 1;
> > +}
> > +
> > +int ioinst_handle_msch(CPUS390XState *env, uint64_t reg1, uint32_t ipb)
> > +{
> > +    int cssid, ssid, schid, m;
> > +    SubchDev *sch;
> > +    SCHIB *schib;
> > +    uint64_t addr;
> > +    int ret = -ENODEV;
> > +    int cc;
> > +
> > +    if (ioinst_disassemble_sch_ident(reg1, &m, &cssid, &ssid, &schid)) {
> > +        program_interrupt(env, PGM_OPERAND, 2);
> > +        return -EIO;
> > +    }
> > +    trace_ioinst_sch_id("msch", cssid, ssid, schid);
> > +    addr = ipb >> 28;
> > +    if (addr > 0) {
> > +        addr = env->regs[addr];
> > +    }
> > +    addr += (ipb & 0xfff0000) >> 16;
> 
> This adds the upper bits twice. Are you sire that's correct?

If addr was 0, it doesn't. If addr was > 0 before, we grabbed the
address from the corresponding register and want to add to it.

> 
> > +    schib = s390_get_address(env, addr);
> > +    if (!schib) {
> > +        program_interrupt(env, PGM_SPECIFICATION, 2);
> > +        return -EIO;
> > +    }
> > +    if (!ioinst_schib_valid(schib)) {
> > +        program_interrupt(env, PGM_OPERAND, 2);
> > +        return -EIO;
> > +    }
> > +    sch = css_find_subch(m, cssid, ssid, schid);
> > +    if (sch && css_subch_visible(sch)) {
> > +        ret = css_do_msch(sch, schib);
> > +    }
> > +    switch (ret) {
> > +    case -ENODEV:
> > +        cc = 3;
> > +        break;
> > +    case -EBUSY:
> > +        cc = 2;
> > +        break;
> > +    case 0:
> > +        cc = 0;
> > +        break;
> > +    default:
> > +        cc = 1;
> > +        break;
> > +    }
> > +
> > +    return cc;
> > +}
> > +
> > +static int ioinst_orb_valid(ORB *orb)
> > +{
> > +    if ((orb->ctrl0 & ORB_CTRL0_MASK_INVALID) ||
> > +        (orb->ctrl1 & ORB_CTRL1_MASK_INVALID)) {
> > +        return 0;
> > +    }
> > +    if ((orb->cpa & 0x80000000) != 0)
> 
> What is this bit's name?

Sigh, perhaps I need more defines...

> 
> > {
> > +        return 0;
> > +    }
> > +    return 1;
> > +}
> > +
> > +int ioinst_handle_ssch(CPUS390XState *env, uint64_t reg1, uint32_t ipb)
> > +{
> > +    int cssid, ssid, schid, m;
> > +    SubchDev *sch;
> > +    ORB *orb;
> > +    uint64_t addr;
> > +    int ret = -ENODEV;
> > +    int cc;
> > +
> > +    if (ioinst_disassemble_sch_ident(reg1, &m, &cssid, &ssid, &schid)) {
> > +        program_interrupt(env, PGM_OPERAND, 2);
> > +        return -EIO;
> > +    }
> > +    trace_ioinst_sch_id("ssch", cssid, ssid, schid);
> > +    addr = ipb >> 28;
> > +    if (addr > 0) {
> > +        addr = env->regs[addr];
> > +    }
> > +    addr += (ipb & 0xfff0000) >> 16;
> 
> Same logic as above. Please combine.

OK, makes sense to write a helper function for this addressing.

> 
> > +    orb = s390_get_address(env, addr);
> > +    if (!orb) {
> > +        program_interrupt(env, PGM_SPECIFICATION, 2);
> > +        return -EIO;
> > +    }
> > +    if (!ioinst_orb_valid(orb)) {
> > +        program_interrupt(env, PGM_OPERAND, 2);
> > +        return -EIO;
> > +    }
> > +    sch = css_find_subch(m, cssid, ssid, schid);
> > +    if (sch && css_subch_visible(sch)) {
> > +        ret = css_do_ssch(sch, orb);
> > +    }
> > +    switch (ret) {
> > +    case -ENODEV:
> > +        cc = 3;
> > +        break;
> > +    case -EBUSY:
> > +        cc = 2;
> > +        break;
> > +    case 0:
> > +        cc = 0;
> > +        break;
> > +    default:
> > +        cc = 1;
> > +        break;
> > +    }
> 
> In fact I've seen this one multiple times too now. Please extract the retval->cc conversion into a function.

Hm. It's somewhat generic (as in use for several instructions), but not
completely generic. Will think about it.

> 
> > +
> > +    return cc;
> > +}
> > +
> > +int ioinst_handle_stcrw(CPUS390XState *env, uint32_t ipb)
> > +{
> > +    CRW *crw;
> > +    uint64_t addr;
> > +    int cc;
> > +
> > +    addr = ipb >> 28;
> > +    if (addr > 0) {
> > +        addr = env->regs[addr];
> > +    }
> > +    addr += (ipb & 0xfff0000) >> 16;
> > +    crw = s390_get_address(env, addr);
> > +    if (!crw) {
> > +        program_interrupt(env, PGM_SPECIFICATION, 2);
> > +        return -EIO;
> > +    }
> > +    if (addr < 8192) {
> > +        addr += env->psa;
> > +    } else if ((env->psa <= addr) && (addr < env->psa + 8192)) {
> > +        addr -= env->psa;
> > +    }
> 
> Eh :)

Hm...

> 
> > +    cc = css_do_stcrw(addr);
> > +    /* 0 - crw stored, 1 - zeroes stored */
> > +    return cc;
> > +}
> > +
> > +int ioinst_handle_stsch(CPUS390XState *env, uint64_t reg1, uint32_t ipb)
> > +{
> > +    int cssid, ssid, schid, m;
> > +    SubchDev *sch;
> > +    uint64_t addr;
> > +    int cc;
> > +
> > +    if (ioinst_disassemble_sch_ident(reg1, &m, &cssid, &ssid, &schid)) {
> > +        program_interrupt(env, PGM_OPERAND, 2);
> > +        return -EIO;
> > +    }
> > +    trace_ioinst_sch_id("stsch", cssid, ssid, schid);
> > +    addr = ipb >> 28;
> > +    if (addr > 0) {
> > +        addr = env->regs[addr];
> > +    }
> > +    addr += (ipb & 0xfff0000) >> 16;
> > +    if (addr < 8192) {
> > +        addr += env->psa;
> > +    } else if ((env->psa <= addr) && (addr < env->psa + 8192)) {
> > +        addr -= env->psa;
> > +    }
> > +    if (!qemu_get_ram_ptr(addr)) {
> > +        program_interrupt(env, PGM_SPECIFICATION, 2);
> > +        return -EIO;
> > +    }
> > +    sch = css_find_subch(m, cssid, ssid, schid);
> > +    if (sch) {
> > +        if (css_subch_visible(sch)) {
> > +            css_do_stsch(sch, addr);
> > +            cc = 0;
> > +        } else {
> > +            /* Indicate no more subchannels in this css/ss */
> > +            cc = 3;
> > +        }
> > +    } else {
> > +        if (css_schid_final(cssid, ssid, schid)) {
> > +            cc = 3; /* No more subchannels in this css/ss */
> > +        } else {
> > +            int i;
> > +
> > +            /* Store an empty schib. */
> > +            for (i = 0; i < sizeof(SCHIB); i++) {
> > +                stb_phys(addr + i, 0);
> > +            }
> > +            cc = 0;
> > +        }
> > +    }
> > +    return cc;
> > +}
> > +
> > +int ioinst_handle_tsch(CPUS390XState *env, uint64_t reg1, uint32_t ipb)
> > +{
> > +    int cssid, ssid, schid, m;
> > +    SubchDev *sch;
> > +    IRB *irb;
> > +    uint64_t addr;
> > +    int ret = -ENODEV;
> > +    int cc;
> > +
> > +    if (ioinst_disassemble_sch_ident(reg1, &m, &cssid, &ssid, &schid)) {
> > +        program_interrupt(env, PGM_OPERAND, 2);
> > +        return -EIO;
> > +    }
> > +    trace_ioinst_sch_id("tsch", cssid, ssid, schid);
> > +    addr = ipb >> 28;
> > +    if (addr > 0) {
> > +        addr = env->regs[addr];
> > +    }
> > +    addr += (ipb & 0xfff0000) >> 16;
> > +    irb = s390_get_address(env, addr);
> > +    if (!irb) {
> > +        program_interrupt(env, PGM_SPECIFICATION, 2);
> > +        return -EIO;
> > +    }
> > +    sch = css_find_subch(m, cssid, ssid, schid);
> > +    if (sch && css_subch_visible(sch)) {
> > +        if (addr < 8192) {
> > +            addr += env->psa;
> > +        } else if ((env->psa <= addr) && (addr < env->psa + 8192)) {
> > +            addr -= env->psa;
> > +        }
> > +        ret = css_do_tsch(sch, addr);
> > +        /* 0 - status pending, 1 - not status pending */
> > +        cc = ret;
> > +    } else {
> > +        cc = 3;
> > +    }
> > +    return cc;
> > +}
> > +
> > +typedef struct ChscReq {
> > +    uint16_t len;
> > +    uint16_t command;
> > +    uint32_t param0;
> > +    uint32_t param1;
> > +    uint32_t param2;
> > +} QEMU_PACKED ChscReq;
> > +
> > +typedef struct ChscResp {
> > +    uint16_t len;
> > +    uint16_t code;
> > +    uint32_t param;
> > +    char data[0];
> > +} QEMU_PACKED ChscResp;
> > +
> > +#define CHSC_SCPD 0x0002
> > +#define CHSC_SCSC 0x0010
> > +#define CHSC_SDA  0x0031
> > +
> > +static void ioinst_handle_chsc_scpd(ChscReq *req, ChscResp *res)
> > +{
> > +    uint16_t resp_code;
> > +    int rfmt;
> > +    uint16_t cssid;
> > +    uint8_t f_chpid, l_chpid;
> > +    int desc_size;
> > +    int m;
> > +
> > +    rfmt = (req->param0 & 0x00000f00) >> 8;
> > +    if ((rfmt == 0) ||  (rfmt == 1)) {
> > +        rfmt = (req->param0 & 0x10000000) >> 28;
> 
> Too many magic numbers.

I can replace them with a slew of one-use magic defines...

> 
> > +    }
> > +    if ((req->len != 0x0010) || (req->param0 & 0xc000f000) ||
> > +        (req->param1 & 0xffffff00) || req->param2) {
> > +        resp_code = 0x0003;
> > +        goto out_err;
> > +    }
> > +    if (req->param0 & 0x0f000000) {
> > +        resp_code = 0x0007;
> > +        goto out_err;
> > +    }
> > +    cssid = (req->param0 & 0x00ff0000) >> 16;
> > +    m = req->param0 & 0x20000000;
> > +    if (cssid != 0) {
> > +        if (!m || !css_present(cssid)) {
> > +            resp_code = 0x0008;
> > +            goto out_err;
> > +        }
> > +    }
> > +    f_chpid = req->param0 & 0x000000ff;
> > +    l_chpid = req->param1 & 0x000000ff;
> > +    if (l_chpid < f_chpid) {
> > +        resp_code = 0x0003;
> > +        goto out_err;
> > +    }
> > +    desc_size = css_collect_chp_desc(m, cssid, f_chpid, l_chpid, rfmt,
> > +                                     &res->data);
> > +    res->code = 0x0001;
> > +    res->len = 8 + desc_size;
> > +    res->param = rfmt;
> > +    return;
> > +
> > +  out_err:
> > +    res->code = resp_code;
> > +    res->len = 8;
> > +    res->param = rfmt;
> > +}
> > +
> > +static void ioinst_handle_chsc_scsc(ChscReq *req, ChscResp *res)
> > +{
> > +    uint8_t cssid;
> > +    uint16_t resp_code;
> > +    uint32_t general_chars[510];
> > +    uint32_t chsc_chars[508];
> > +
> > +    if (req->param0 & 0x000f0000) {
> > +        resp_code = 0x0007;
> > +        goto out_err;
> > +    }
> > +    cssid = (req->param0 & 0x0000ff00) >> 8;
> > +    if (cssid != 0) {
> > +        if (!(req->param0 & 0x20000000) || !css_present(cssid)) {
> > +            resp_code = 0x0008;
> > +            goto out_err;
> > +        }
> > +    }
> > +    if ((req->param0 & 0xdff000ff) || req->param1 || req->param2) {
> > +        resp_code = 0x0003;
> > +        goto out_err;
> > +    }
> > +    res->code = 0x0001;
> > +    res->len = 4080;
> > +    res->param = 0;
> > +
> > +    memset(general_chars, 0, sizeof(general_chars));
> > +    memset(chsc_chars, 0, sizeof(chsc_chars));
> > +
> > +    general_chars[0] = 0x03000000;
> > +    general_chars[1] = 0x00059000;
> > +
> > +    chsc_chars[0] = 0x40000000;
> > +    chsc_chars[3] = 0x00040000;
> > +
> > +    memcpy(res->data, general_chars, sizeof(general_chars));
> > +    memcpy(res->data + sizeof(general_chars), chsc_chars, sizeof(chsc_chars));
> > +    return;
> > +
> > +  out_err:
> > +    res->code = resp_code;
> > +    res->len = 8;
> > +    res->param = 0;
> > +}
> > +
> > +#define CHSC_SDA_OC_MCSSE 0x0
> > +#define CHSC_SDA_OC_MSS 0x2
> > +static void ioinst_handle_chsc_sda(ChscReq *req, ChscResp *res)
> > +{
> > +    uint16_t resp_code = 0x0001;
> > +    uint16_t oc;
> > +    int ret;
> > +
> > +    if ((req->len != 0x0400) || (req->param0 & 0xf0ff0000)) {
> > +        resp_code = 0x0003;
> > +        goto out;
> > +    }
> > +
> > +    if (req->param0 & 0x0f000000) {
> > +        resp_code = 0x0007;
> > +        goto out;
> > +    }
> > +
> > +    oc = req->param0 & 0x0000ffff;
> > +    switch (oc) {
> > +    case CHSC_SDA_OC_MCSSE:
> > +        ret = css_enable_mcsse();
> > +        if (ret == -EINVAL) {
> > +            resp_code = 0x0101;
> > +            goto out;
> > +        }
> > +        break;
> > +    case CHSC_SDA_OC_MSS:
> > +        ret = css_enable_mss();
> > +        if (ret == -EINVAL) {
> > +            resp_code = 0x0101;
> > +            goto out;
> > +        }
> > +        break;
> > +    default:
> > +        resp_code = 0x0003;
> > +        goto out;
> > +    }
> > +
> > +out:
> > +    res->code = resp_code;
> > +    res->len = 8;
> > +    res->param = 0;
> > +}
> > +
> > +static void ioinst_handle_chsc_unimplemented(ChscResp *res)
> > +{
> > +    res->len = 8;
> > +    res->code = 0x0004;
> > +    res->param = 0;
> > +}
> > +
> > +int ioinst_handle_chsc(CPUS390XState *env, uint32_t ipb)
> > +{
> > +    ChscReq *req;
> > +    ChscResp *res;
> > +    uint64_t addr;
> > +    int reg;
> > +
> > +    trace_ioinst("chsc");
> > +    reg = (ipb >> 20) & 0x00f;
> > +    addr = env->regs[reg];
> > +    req = s390_get_address(env, addr);
> > +    if (!req) {
> > +        program_interrupt(env, PGM_SPECIFICATION, 2);
> > +        return -EIO;
> > +    }
> > +    if (!env->chsc_page) {
> > +        env->chsc_page = g_malloc0(TARGET_PAGE_SIZE);
> 
> Just make it an actual part of the struct, no need for the extra allocation.

Is having an extra page per cpu by default fine? If yes, I can do so.

> 
> Alex
> 
> > +    } else {
> > +        memset(env->chsc_page, 0, TARGET_PAGE_SIZE);
> > +    }
> > +    res = env->chsc_page;
> > +    trace_ioinst_chsc_cmd(req->command, req->len);
> > +    switch (req->command) {
> > +    case CHSC_SCSC:
> > +        ioinst_handle_chsc_scsc(req, res);
> > +        break;
> > +    case CHSC_SCPD:
> > +        ioinst_handle_chsc_scpd(req, res);
> > +        break;
> > +    case CHSC_SDA:
> > +        ioinst_handle_chsc_sda(req, res);
> > +        break;
> > +    default:
> > +        ioinst_handle_chsc_unimplemented(res);
> > +        break;
> > +    }
> > +    if (addr < 8192) {
> > +        addr += env->psa;
> > +    } else if ((env->psa <= addr) && (addr < env->psa + 8192)) {
> > +        addr -= env->psa;
> > +    }
> > +    cpu_physical_memory_write(addr + req->len, res, res->len);
> > +    return 0;
> > +}
> > +
> > +int ioinst_handle_tpi(CPUS390XState *env, uint32_t ipb)
> > +{
> > +    uint64_t addr;
> > +    int lowcore;
> > +
> > +    trace_ioinst("tpi");
> > +    addr = ipb >> 28;
> > +    if (addr > 0) {
> > +        addr = env->regs[addr];
> > +    }
> > +    addr += (ipb & 0xfff0000) >> 16;
> > +    lowcore = addr ? 0 : 1;
> > +    if (addr < 8192) {
> > +        addr += env->psa;
> > +    } else if ((env->psa <= addr) && (addr < env->psa + 8192)) {
> > +        addr -= env->psa;
> > +    }
> > +    return css_do_tpi(addr, lowcore);
> > +}
> > +
> > +int ioinst_handle_schm(CPUS390XState *env, uint64_t reg1, uint64_t reg2,
> > +                       uint32_t ipb)
> > +{
> > +    uint8_t mbk;
> > +    int update;
> > +    int dct;
> > +
> > +    trace_ioinst("schm");
> > +
> > +    if (reg1 & 0x000000000ffffffc) {
> > +        program_interrupt(env, PGM_OPERAND, 2);
> > +        return -EIO;
> > +    }
> > +
> > +    mbk = (reg1 & 0x00000000f0000000) >> 28;
> > +    update = (reg1 & 0x0000000000000002) >> 1;
> > +    dct = reg1 & 0x0000000000000001;
> > +
> > +    if (update && (reg2 & 0x0000000000000fff)) {
> > +        program_interrupt(env, PGM_OPERAND, 2);
> > +        return -EIO;
> > +    }
> > +
> > +    css_do_schm(mbk, update, dct, update ? reg2 : 0);
> > +
> > +    return 0;
> > +}
> > +
> > +int ioinst_handle_rsch(CPUS390XState *env, uint64_t reg1)
> > +{
> > +    int cssid, ssid, schid, m;
> > +    SubchDev *sch;
> > +    int ret = -ENODEV;
> > +    int cc;
> > +
> > +    if (ioinst_disassemble_sch_ident(reg1, &m, &cssid, &ssid, &schid)) {
> > +        program_interrupt(env, PGM_OPERAND, 2);
> > +        return -EIO;
> > +    }
> > +    trace_ioinst_sch_id("rsch", cssid, ssid, schid);
> > +    sch = css_find_subch(m, cssid, ssid, schid);
> > +    if (sch && css_subch_visible(sch)) {
> > +        ret = css_do_rsch(sch);
> > +    }
> > +    switch (ret) {
> > +    case -ENODEV:
> > +        cc = 3;
> > +        break;
> > +    case -EINVAL:
> > +        cc = 2;
> > +        break;
> > +    case 0:
> > +        cc = 0;
> > +        break;
> > +    default:
> > +        cc = 1;
> > +        break;
> > +    }
> > +
> > +    return cc;
> > +
> > +}
> > +
> > +int ioinst_handle_rchp(CPUS390XState *env, uint64_t reg1)
> > +{
> > +    int cc;
> > +    uint8_t cssid;
> > +    uint8_t chpid;
> > +    int ret;
> > +
> > +    if (reg1 & 0xff00ff00) {
> > +        program_interrupt(env, PGM_OPERAND, 2);
> > +        return -EIO;
> > +    }
> > +
> > +    cssid = (reg1 >> 16) & 0xff;
> > +    chpid = reg1 & 0xff;
> > +
> > +    trace_ioinst_chp_id("rchp", cssid, chpid);
> > +
> > +    ret = css_do_rchp(cssid, chpid);
> > +
> > +    switch (ret) {
> > +    case -ENODEV:
> > +        cc = 3;
> > +        break;
> > +    case -EBUSY:
> > +        cc = 2;
> > +        break;
> > +    case 0:
> > +        cc = 0;
> > +        break;
> > +    default:
> > +        /* Invalid channel subsystem. */
> > +        program_interrupt(env, PGM_OPERAND, 2);
> > +        return -EIO;
> > +    }
> > +
> > +    return cc;
> > +}
> > +
> > +int ioinst_handle_sal(CPUS390XState *env, uint64_t reg1)
> > +{
> > +    /* We do not provide address limit checking, so let's suppress it. */
> > +    if (env->regs[1] & 0x000000008000ffff) {
> > +        program_interrupt(env, PGM_OPERAND, 2);
> > +        return -EIO;
> > +    }
> > +    return 0;
> > +}
> > diff --git a/target-s390x/ioinst.h b/target-s390x/ioinst.h
> > index b5b4a03..e5f54f5 100644
> > --- a/target-s390x/ioinst.h
> > +++ b/target-s390x/ioinst.h
> > @@ -204,4 +204,20 @@ typedef struct CRW {
> > 
> > int ioinst_disassemble_sch_ident(uint32_t value, int *m, int *cssid, int *ssid,
> >                                  int *schid);
> > +int ioinst_handle_xsch(CPUS390XState *env, uint64_t reg1);
> > +int ioinst_handle_csch(CPUS390XState *env, uint64_t reg1);
> > +int ioinst_handle_hsch(CPUS390XState *env, uint64_t reg1);
> > +int ioinst_handle_msch(CPUS390XState *env, uint64_t reg1, uint32_t ipb);
> > +int ioinst_handle_ssch(CPUS390XState *env, uint64_t reg1, uint32_t ipb);
> > +int ioinst_handle_stcrw(CPUS390XState *env, uint32_t ipb);
> > +int ioinst_handle_stsch(CPUS390XState *env, uint64_t reg1, uint32_t ipb);
> > +int ioinst_handle_tsch(CPUS390XState *env, uint64_t reg1, uint32_t ipb);
> > +int ioinst_handle_chsc(CPUS390XState *env, uint32_t ipb);
> > +int ioinst_handle_tpi(CPUS390XState *env, uint32_t ipb);
> > +int ioinst_handle_schm(CPUS390XState *env, uint64_t reg1, uint64_t reg2,
> > +                       uint32_t ipb);
> > +int ioinst_handle_rsch(CPUS390XState *env, uint64_t reg1);
> > +int ioinst_handle_rchp(CPUS390XState *env, uint64_t reg1);
> > +int ioinst_handle_sal(CPUS390XState *env, uint64_t reg1);
> > +
> > #endif
> > diff --git a/trace-events b/trace-events
> > index 6c6cbf1..af50c68 100644
> > --- a/trace-events
> > +++ b/trace-events
> > @@ -1022,3 +1022,9 @@ spapr_pci_rtas_ibm_change_msi(unsigned func, unsigned req) "func %u, requested %
> > spapr_pci_rtas_ibm_query_interrupt_source_number(unsigned ioa, unsigned intr) "queries for #%u, IRQ%u"
> > spapr_pci_msi_write(uint64_t addr, uint64_t data, uint32_t dt_irq) "@%"PRIx64"<=%"PRIx64" IRQ %u"
> > spapr_pci_lsi_set(const char *busname, int pin, uint32_t irq) "%s PIN%d IRQ %u"
> > +
> > +# target-s390x/ioinst.c
> > +ioinst(const char *insn) "IOINST: %s"
> > +ioinst_sch_id(const char *insn, int cssid, int ssid, int schid) "IOINST: %s (%x.%x.%04x)"
> > +ioinst_chp_id(const char *insn, int cssid, int chpid) "IOINST: %s (%x.%02x)"
> > +ioinst_chsc_cmd(uint16_t cmd, uint16_t len) "IOINST: chsc command %04x, len %04x"
> > -- 
> > 1.7.12.4
> > 
>