Simplify the error handling of the SSCH and RSCH handler avoiding arbitrary and cryptic error codes being mapped to what a subchannel is supposed to do. Let the code detecting the condition tell how it's to be handled in a less ambiguous way. It's best to handle SSCH and RSCH in one go as the emulation of the two shares a lot of code.
Signed-off-by: Halil Pasic <pa...@linux.vnet.ibm.com> Acked-by: Pierre Morel<pmo...@linux.vnet.ibm.com> --- Notes: Funny, we had a different swich-case for SSCH and RSCH. For virtual it did not matter, but for passtrough it could. In practice -EINVAL from the kernel would have been mapped to cc 2 in case of RSCH and to cc 1 in case of SSHC which is absurd. Same goes for -EBUSY from kernel which is correctly mapped to cc 2 in case of SSCH, but for RSCH it gets mapped to cc 1 which is also absurd. --- hw/s390x/css.c | 86 ++++++++++++++------------------------------- hw/s390x/s390-ccw.c | 8 ++--- hw/vfio/ccw.c | 32 +++++++++++++---- include/hw/s390x/css.h | 30 ++++++++++++---- include/hw/s390x/s390-ccw.h | 2 +- target/s390x/ioinst.c | 61 +++++++++----------------------- 6 files changed, 97 insertions(+), 122 deletions(-) diff --git a/hw/s390x/css.c b/hw/s390x/css.c index bc47bf5b20..1102642c10 100644 --- a/hw/s390x/css.c +++ b/hw/s390x/css.c @@ -1015,12 +1015,11 @@ static void sch_handle_start_func_virtual(SubchDev *sch) } -static int sch_handle_start_func_passthrough(SubchDev *sch) +static void sch_handle_start_func_passthrough(SubchDev *sch) { PMCW *p = &sch->curr_status.pmcw; SCSW *s = &sch->curr_status.scsw; - int ret; ORB *orb = &sch->orb; if (!(s->ctrl & SCSW_ACTL_SUSP)) { @@ -1034,28 +1033,10 @@ static int sch_handle_start_func_passthrough(SubchDev *sch) */ if (!(orb->ctrl0 & ORB_CTRL0_MASK_PFCH) || !(orb->ctrl0 & ORB_CTRL0_MASK_C64)) { - return -ENODEV; + sch->iret.cc = 3; } - ret = s390_ccw_cmd_request(orb, s, sch->driver_data); - switch (ret) { - /* Currently we don't update control block and just return the cc code. */ - case 0: - break; - case -EBUSY: - break; - case -ENODEV: - break; - case -EFAULT: - break; - case -EACCES: - /* Let's reflect an inaccessible host device by cc 3. */ - default: - /* Let's make all other return codes map to cc 3. */ - ret = -ENODEV; - }; - - return ret; + s390_ccw_cmd_request(sch); } /* @@ -1064,7 +1045,7 @@ static int sch_handle_start_func_passthrough(SubchDev *sch) * read/writes) asynchronous later on if we start supporting more than * our current very simple devices. */ -int do_subchannel_work_virtual(SubchDev *sch) +void do_subchannel_work_virtual(SubchDev *sch) { SCSW *s = &sch->curr_status.scsw; @@ -1078,41 +1059,35 @@ int do_subchannel_work_virtual(SubchDev *sch) sch_handle_start_func_virtual(sch); } else { /* Cannot happen. */ - return -ENODEV; + sch->iret.cc = 3; } css_inject_io_interrupt(sch); - return 0; } -int do_subchannel_work_passthrough(SubchDev *sch) +void do_subchannel_work_passthrough(SubchDev *sch) { - int ret; SCSW *s = &sch->curr_status.scsw; if (s->ctrl & SCSW_FCTL_CLEAR_FUNC) { /* TODO: Clear handling */ sch_handle_clear_func(sch); - ret = 0; } else if (s->ctrl & SCSW_FCTL_HALT_FUNC) { /* TODO: Halt handling */ sch_handle_halt_func(sch); - ret = 0; } else if (s->ctrl & SCSW_FCTL_START_FUNC) { - ret = sch_handle_start_func_passthrough(sch); + sch_handle_start_func_passthrough(sch); } else { /* Cannot happen. */ - return -ENODEV; + sch->iret.cc = 3; } - - return ret; } -static int do_subchannel_work(SubchDev *sch) +static void do_subchannel_work(SubchDev *sch) { if (sch->do_subchannel_work) { - return sch->do_subchannel_work(sch); + sch->do_subchannel_work(sch); } else { - return -ENODEV; + sch->iret.cc = 3; } } @@ -1400,27 +1375,26 @@ static void css_update_chnmon(SubchDev *sch) } } -int css_do_ssch(SubchDev *sch, ORB *orb) +void css_do_ssch(SubchDev *sch, ORB *orb) { SCSW *s = &sch->curr_status.scsw; PMCW *p = &sch->curr_status.pmcw; - int ret; if (~(p->flags) & (PMCW_FLAGS_MASK_DNV | PMCW_FLAGS_MASK_ENA)) { - ret = -ENODEV; - goto out; + sch->iret.cc = 3; + return; } if (s->ctrl & SCSW_STCTL_STATUS_PEND) { - ret = -EINPROGRESS; - goto out; + sch->iret.cc = 1; + return; } if (s->ctrl & (SCSW_FCTL_START_FUNC | SCSW_FCTL_HALT_FUNC | SCSW_FCTL_CLEAR_FUNC)) { - ret = -EBUSY; - goto out; + sch->iret.cc = 2; + return; } /* If monitoring is active, update counter. */ @@ -1433,10 +1407,7 @@ int css_do_ssch(SubchDev *sch, ORB *orb) s->ctrl |= (SCSW_FCTL_START_FUNC | SCSW_ACTL_START_PEND); s->flags &= ~SCSW_FLAGS_MASK_PNO; - ret = do_subchannel_work(sch); - -out: - return ret; + do_subchannel_work(sch); } static void copy_irb_to_guest(IRB *dest, const IRB *src, PMCW *pmcw, @@ -1683,27 +1654,26 @@ void css_do_schm(uint8_t mbk, int update, int dct, uint64_t mbo) } } -int css_do_rsch(SubchDev *sch) +void css_do_rsch(SubchDev *sch) { SCSW *s = &sch->curr_status.scsw; PMCW *p = &sch->curr_status.pmcw; - int ret; if (~(p->flags) & (PMCW_FLAGS_MASK_DNV | PMCW_FLAGS_MASK_ENA)) { - ret = -ENODEV; - goto out; + sch->iret.cc = 3; + return; } if (s->ctrl & SCSW_STCTL_STATUS_PEND) { - ret = -EINPROGRESS; - goto out; + sch->iret.cc = 1; + return; } if (((s->ctrl & SCSW_CTRL_MASK_FCTL) != SCSW_FCTL_START_FUNC) || (s->ctrl & SCSW_ACTL_RESUME_PEND) || (!(s->ctrl & SCSW_ACTL_SUSP))) { - ret = -EINVAL; - goto out; + sch->iret.cc = 2; + return; } /* If monitoring is active, update counter. */ @@ -1713,10 +1683,6 @@ int css_do_rsch(SubchDev *sch) s->ctrl |= SCSW_ACTL_RESUME_PEND; do_subchannel_work(sch); - ret = 0; - -out: - return ret; } int css_do_rchp(uint8_t cssid, uint8_t chpid) diff --git a/hw/s390x/s390-ccw.c b/hw/s390x/s390-ccw.c index 2b0741741c..fa0947894d 100644 --- a/hw/s390x/s390-ccw.c +++ b/hw/s390x/s390-ccw.c @@ -18,14 +18,14 @@ #include "hw/s390x/css-bridge.h" #include "hw/s390x/s390-ccw.h" -int s390_ccw_cmd_request(ORB *orb, SCSW *scsw, void *data) +void s390_ccw_cmd_request(SubchDev *sch) { - S390CCWDeviceClass *cdc = S390_CCW_DEVICE_GET_CLASS(data); + S390CCWDeviceClass *cdc = S390_CCW_DEVICE_GET_CLASS(sch->driver_data); if (cdc->handle_request) { - return cdc->handle_request(orb, scsw, data); + cdc->handle_request(sch); } else { - return -ENODEV; + sch->iret.cc = 3; } } diff --git a/hw/vfio/ccw.c b/hw/vfio/ccw.c index a8baadf57a..b2827ce987 100644 --- a/hw/vfio/ccw.c +++ b/hw/vfio/ccw.c @@ -23,6 +23,7 @@ #include "hw/s390x/s390-ccw.h" #include "hw/s390x/ccw-device.h" #include "qemu/error-report.h" +#include "cpu.h" #define TYPE_VFIO_CCW "vfio-ccw" typedef struct VFIOCCWDevice { @@ -47,9 +48,9 @@ struct VFIODeviceOps vfio_ccw_ops = { .vfio_compute_needs_reset = vfio_ccw_compute_needs_reset, }; -static int vfio_ccw_handle_request(ORB *orb, SCSW *scsw, void *data) +static void vfio_ccw_handle_request(SubchDev *sch) { - S390CCWDevice *cdev = data; + S390CCWDevice *cdev = sch->driver_data; VFIOCCWDevice *vcdev = DO_UPCAST(VFIOCCWDevice, cdev, cdev); struct ccw_io_region *region = vcdev->io_region; int ret; @@ -60,8 +61,8 @@ static int vfio_ccw_handle_request(ORB *orb, SCSW *scsw, void *data) memset(region, 0, sizeof(*region)); - memcpy(region->orb_area, orb, sizeof(ORB)); - memcpy(region->scsw_area, scsw, sizeof(SCSW)); + memcpy(region->orb_area, &sch->orb, sizeof(ORB)); + memcpy(region->scsw_area, &sch->curr_status.scsw, sizeof(SCSW)); again: ret = pwrite(vcdev->vdev.fd, region, @@ -71,10 +72,27 @@ again: goto again; } error_report("vfio-ccw: wirte I/O region failed with errno=%d", errno); - return -errno; + ret = -errno; + } else { + ret = region->ret_code; + } + switch (-ret) { + /* Currently we don't update control block and just return the cc code. */ + case 0: + sch->iret.cc = 0; + break; + case EBUSY: + sch->iret.cc = 2; + break; + case EFAULT: + sch->iret.pgm_chk = true; + sch->iret.irq_code = PGM_ADDRESSING; + break; + case ENODEV: + case EACCES: + default: + sch->iret.cc = 3; } - - return region->ret_code; } static void vfio_ccw_reset(DeviceState *dev) diff --git a/include/hw/s390x/css.h b/include/hw/s390x/css.h index 5c5fe6b202..d093181a9e 100644 --- a/include/hw/s390x/css.h +++ b/include/hw/s390x/css.h @@ -94,13 +94,31 @@ struct SubchDev { /* transport-provided data: */ int (*ccw_cb) (SubchDev *, CCW1); void (*disable_cb)(SubchDev *); - int (*do_subchannel_work) (SubchDev *); + void (*do_subchannel_work) (SubchDev *); SenseId id; void *driver_data; + /* io instructions conclude according to iret */ + struct { + /* + * General semantic of cc codes of IO instructions is (brief): + * 0 -- produced expected result + * 1 -- produced alternate result + * 2 -- ineffective, because busy with previously initiated function + * 3 -- ineffective, not operational + */ + uint32_t cc:4; + bool pgm_chk:1; + uint32_t irq_code; + } iret; }; extern const VMStateDescription vmstate_subch_dev; +static inline void css_subch_clear_iret(SubchDev *sch) +{ + memset(&sch->iret, 0, sizeof(sch->iret)); +} + /* * Identify a device within the channel subsystem. * Note that this can be used to identify either the subchannel or @@ -156,9 +174,9 @@ void css_generate_sch_crws(uint8_t cssid, uint8_t ssid, uint16_t schid, void css_generate_chp_crws(uint8_t cssid, uint8_t chpid); void css_generate_css_crws(uint8_t cssid); void css_clear_sei_pending(void); -int s390_ccw_cmd_request(ORB *orb, SCSW *scsw, void *data); -int do_subchannel_work_virtual(SubchDev *sub); -int do_subchannel_work_passthrough(SubchDev *sub); +void s390_ccw_cmd_request(SubchDev *sch); +void do_subchannel_work_virtual(SubchDev *sub); +void do_subchannel_work_passthrough(SubchDev *sub); typedef enum { CSS_IO_ADAPTER_VIRTIO = 0, @@ -189,7 +207,7 @@ int css_do_msch(SubchDev *sch, const SCHIB *schib); int css_do_xsch(SubchDev *sch); int css_do_csch(SubchDev *sch); int css_do_hsch(SubchDev *sch); -int css_do_ssch(SubchDev *sch, ORB *orb); +void css_do_ssch(SubchDev *sch, ORB *orb); int css_do_tsch_get_irb(SubchDev *sch, IRB *irb, int *irb_len); void css_do_tsch_update_subch(SubchDev *sch); int css_do_stcrw(CRW *crw); @@ -200,7 +218,7 @@ int css_collect_chp_desc(int m, uint8_t cssid, uint8_t f_chpid, uint8_t l_chpid, void css_do_schm(uint8_t mbk, int update, int dct, uint64_t mbo); int css_enable_mcsse(void); int css_enable_mss(void); -int css_do_rsch(SubchDev *sch); +void css_do_rsch(SubchDev *sch); int css_do_rchp(uint8_t cssid, uint8_t chpid); bool css_present(uint8_t cssid); #endif diff --git a/include/hw/s390x/s390-ccw.h b/include/hw/s390x/s390-ccw.h index 9f45cf1347..d2159c9ed7 100644 --- a/include/hw/s390x/s390-ccw.h +++ b/include/hw/s390x/s390-ccw.h @@ -33,7 +33,7 @@ typedef struct S390CCWDeviceClass { CCWDeviceClass parent_class; void (*realize)(S390CCWDevice *dev, char *sysfsdev, Error **errp); void (*unrealize)(S390CCWDevice *dev, Error **errp); - int (*handle_request) (ORB *, SCSW *, void *); + void (*handle_request) (SubchDev *sch); } S390CCWDeviceClass; #endif diff --git a/target/s390x/ioinst.c b/target/s390x/ioinst.c index 51fbea620d..e8044068c2 100644 --- a/target/s390x/ioinst.c +++ b/target/s390x/ioinst.c @@ -217,8 +217,6 @@ void ioinst_handle_ssch(S390CPU *cpu, uint64_t reg1, uint32_t ipb) SubchDev *sch; ORB orig_orb, orb; uint64_t addr; - int ret = -ENODEV; - int cc; CPUS390XState *env = &cpu->env; uint8_t ar; @@ -238,33 +236,17 @@ void ioinst_handle_ssch(S390CPU *cpu, uint64_t reg1, uint32_t ipb) } trace_ioinst_sch_id("ssch", cssid, ssid, schid); sch = css_find_subch(m, cssid, ssid, schid); - if (sch && css_subch_visible(sch)) { - ret = css_do_ssch(sch, &orb); + if (!sch || !css_subch_visible(sch)) { + setcc(cpu, 3); + return; } - switch (ret) { - case -ENODEV: - cc = 3; - break; - case -EBUSY: - cc = 2; - break; - case -EFAULT: - /* - * TODO: - * I'm wondering whether there is something better - * to do for us here (like setting some device or - * subchannel status). - */ - program_interrupt(env, PGM_ADDRESSING, 4); + css_subch_clear_iret(sch); + css_do_ssch(sch, &orb); + if (sch->iret.pgm_chk) { + program_interrupt(env, sch->iret.irq_code, 4); return; - case 0: - cc = 0; - break; - default: - cc = 1; - break; } - setcc(cpu, cc); + setcc(cpu, sch->iret.cc); } void ioinst_handle_stcrw(S390CPU *cpu, uint32_t ipb) @@ -767,8 +749,6 @@ void ioinst_handle_rsch(S390CPU *cpu, 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(&cpu->env, PGM_OPERAND, 4); @@ -776,24 +756,17 @@ void ioinst_handle_rsch(S390CPU *cpu, uint64_t reg1) } 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); + if (!sch || !css_subch_visible(sch)) { + setcc(cpu, 3); + return; } - switch (ret) { - case -ENODEV: - cc = 3; - break; - case -EINVAL: - cc = 2; - break; - case 0: - cc = 0; - break; - default: - cc = 1; - break; + css_subch_clear_iret(sch); + css_do_rsch(sch); + if (sch->iret.pgm_chk) { + program_interrupt(&cpu->env, sch->iret.irq_code, 4); + return; } - setcc(cpu, cc); + setcc(cpu, sch->iret.cc); } #define RCHP_REG1_RES(_reg) (_reg & 0x00000000ff00ff00) -- 2.13.5