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One of several bugs here is known-but-compiled-out subops falling into the default chain and hitting unrelated logic. Remove the CONFIG_GDBSX ifdefary in arch_do_domctl() by implementing gdbsx_domctl() and moving the logic across. As minor cleanup, * gdbsx_guest_mem_io() can become static * Remove opencoding of domain_vcpu() and %pd Signed-off-by: Andrew Cooper Reviewed-by: Jan Beulich --- CC: George Dunlap CC: Jan Beulich CC: Stefano Stabellini CC: Wei Liu CC: Julien Grall CC: Juergen Gross CC: Roger Pau MonnĂ© CC: Volodymyr Babchuk CC: Bertrand Marquis v2: * Implement the "split into new function" approach from the RFC. v3: * Switch to int. * Insert missing break. * static inline for stub. --- xen/arch/x86/domctl.c | 61 +--------------------------------- xen/arch/x86/gdbsx.c | 70 +++++++++++++++++++++++++++++++++++++++- xen/arch/x86/include/asm/gdbsx.h | 16 +++++++-- 3 files changed, 83 insertions(+), 64 deletions(-) diff --git a/xen/arch/x86/domctl.c b/xen/arch/x86/domctl.c index c20ab4352715..9131acb8a230 100644 --- a/xen/arch/x86/domctl.c +++ b/xen/arch/x86/domctl.c @@ -816,71 +816,12 @@ long arch_do_domctl( } #endif -#ifdef CONFIG_GDBSX case XEN_DOMCTL_gdbsx_guestmemio: - ret = gdbsx_guest_mem_io(d, &domctl->u.gdbsx_guest_memio); - if ( !ret ) - copyback = true; - break; - case XEN_DOMCTL_gdbsx_pausevcpu: - { - struct vcpu *v; - - ret = -EBUSY; - if ( !d->controller_pause_count ) - break; - ret = -EINVAL; - if ( domctl->u.gdbsx_pauseunp_vcpu.vcpu >= d->max_vcpus || - (v = d->vcpu[domctl->u.gdbsx_pauseunp_vcpu.vcpu]) == NULL ) - break; - ret = vcpu_pause_by_systemcontroller(v); - break; - } - case XEN_DOMCTL_gdbsx_unpausevcpu: - { - struct vcpu *v; - - ret = -EBUSY; - if ( !d->controller_pause_count ) - break; - ret = -EINVAL; - if ( domctl->u.gdbsx_pauseunp_vcpu.vcpu >= d->max_vcpus || - (v = d->vcpu[domctl->u.gdbsx_pauseunp_vcpu.vcpu]) == NULL ) - break; - ret = vcpu_unpause_by_systemcontroller(v); - if ( ret == -EINVAL ) - printk(XENLOG_G_WARNING - "WARN: d%d attempting to unpause %pv which is not paused\n", - currd->domain_id, v); - break; - } - case XEN_DOMCTL_gdbsx_domstatus: - { - struct vcpu *v; - - domctl->u.gdbsx_domstatus.vcpu_id = -1; - domctl->u.gdbsx_domstatus.paused = d->controller_pause_count > 0; - if ( domctl->u.gdbsx_domstatus.paused ) - { - for_each_vcpu ( d, v ) - { - if ( v->arch.gdbsx_vcpu_event ) - { - domctl->u.gdbsx_domstatus.vcpu_id = v->vcpu_id; - domctl->u.gdbsx_domstatus.vcpu_ev = - v->arch.gdbsx_vcpu_event; - v->arch.gdbsx_vcpu_event = 0; - break; - } - } - } - copyback = true; + ret = gdbsx_domctl(d, domctl, ©back); break; - } -#endif case XEN_DOMCTL_setvcpuextstate: case XEN_DOMCTL_getvcpuextstate: diff --git a/xen/arch/x86/gdbsx.c b/xen/arch/x86/gdbsx.c index 6ef46e8ea77d..21442f5dff1a 100644 --- a/xen/arch/x86/gdbsx.c +++ b/xen/arch/x86/gdbsx.c @@ -152,7 +152,8 @@ static unsigned int dbg_rw_guest_mem(struct domain *dp, unsigned long addr, return len; } -int gdbsx_guest_mem_io(struct domain *d, struct xen_domctl_gdbsx_memio *iop) +static int gdbsx_guest_mem_io( + struct domain *d, struct xen_domctl_gdbsx_memio *iop) { if ( d && !d->is_dying ) { @@ -178,6 +179,73 @@ void domain_pause_for_debugger(void) send_global_virq(VIRQ_DEBUGGER); } +int gdbsx_domctl(struct domain *d, struct xen_domctl *domctl, bool *copyback) +{ + struct vcpu *v; + int ret; + + switch ( domctl->cmd ) + { + case XEN_DOMCTL_gdbsx_guestmemio: + ret = gdbsx_guest_mem_io(d, &domctl->u.gdbsx_guest_memio); + if ( !ret ) + *copyback = true; + break; + + case XEN_DOMCTL_gdbsx_pausevcpu: + ret = -EBUSY; + if ( !d->controller_pause_count ) + break; + ret = -EINVAL; + if ( (v = domain_vcpu(d, domctl->u.gdbsx_pauseunp_vcpu.vcpu)) == NULL ) + break; + ret = vcpu_pause_by_systemcontroller(v); + break; + + case XEN_DOMCTL_gdbsx_unpausevcpu: + ret = -EBUSY; + if ( !d->controller_pause_count ) + break; + ret = -EINVAL; + if ( (v = domain_vcpu(d, domctl->u.gdbsx_pauseunp_vcpu.vcpu)) == NULL ) + break; + ret = vcpu_unpause_by_systemcontroller(v); + if ( ret == -EINVAL ) + printk(XENLOG_G_WARNING + "WARN: %pd attempting to unpause %pv which is not paused\n", + current->domain, v); + break; + + case XEN_DOMCTL_gdbsx_domstatus: + ret = 0; + domctl->u.gdbsx_domstatus.vcpu_id = -1; + domctl->u.gdbsx_domstatus.paused = d->controller_pause_count > 0; + if ( domctl->u.gdbsx_domstatus.paused ) + { + for_each_vcpu ( d, v ) + { + if ( v->arch.gdbsx_vcpu_event ) + { + domctl->u.gdbsx_domstatus.vcpu_id = v->vcpu_id; + domctl->u.gdbsx_domstatus.vcpu_ev = + v->arch.gdbsx_vcpu_event; + v->arch.gdbsx_vcpu_event = 0; + break; + } + } + } + *copyback = true; + break; + + default: + ASSERT_UNREACHABLE(); + ret = -ENOSYS; + break; + } + + return ret; +} + /* * Local variables: * mode: C diff --git a/xen/arch/x86/include/asm/gdbsx.h b/xen/arch/x86/include/asm/gdbsx.h index 938eb74e2e25..e906be9ea318 100644 --- a/xen/arch/x86/include/asm/gdbsx.h +++ b/xen/arch/x86/include/asm/gdbsx.h @@ -2,18 +2,28 @@ #ifndef __X86_GDBX_H__ #define __X86_GDBX_H__ -#ifdef CONFIG_GDBSX +#include struct domain; -struct xen_domctl_gdbsx_memio; +struct xen_domctl; -int gdbsx_guest_mem_io(struct domain *d, struct xen_domctl_gdbsx_memio *iop); +#ifdef CONFIG_GDBSX void domain_pause_for_debugger(void); +int gdbsx_domctl(struct domain *d, struct xen_domctl *domctl, bool *copyback); + #else +#include + static inline void domain_pause_for_debugger(void) {} +static inline int gdbsx_domctl( + struct domain *d, struct xen_domctl *domctl, bool *copyback) +{ + return -ENOSYS; +} + #endif /* CONFIG_GDBSX */ #endif /* __X86_GDBX_H__ */