| Message ID | 20250331214321.205331-4-jason.andryuk@amd.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | ARM split hardware and control domains | expand |
On Mon, 31 Mar 2025, Jason Andryuk wrote: > To allocate the xenstore event channel and initialize the grant table > entry, the xenstore domid is neeed. A dom0 is created before the domUs, > so it is normally available through hardware_domain. With capabilities > and dom0less, the xenstore domain may not be created first. > > Keep the population of the page and HVM_PARAM_STORE_PFN in the normal > domain construction, but delay event channel creation and grant seeding > to after all domUs are created. HVM_PARAM_STORE_PFN now serves as > indication to setup xenstore since the device tree is no longer > immediately available. 0 means no xenstore. ~0ULL means legacy so only > the event channel needs setup, and any other value means to seed the > page. > > dom0 needs to set xs_domid when it is serving as the xenstore domain. > > The domain running xenstored needs to be the handler for VIRQ_DOM_EXC, > so set that as well - it otherwise defaults to hardware domain. > > Signed-off-by: Jason Andryuk <jason.andryuk@amd.com> > --- > v2: > Re-order ahead of seeding. > Fix created type in commit message > Change set_xs_domid to set_xs_domain > Set xenstore domain as VIRQ_DOM_EXC handler > > Signed-off-by: Jason Andryuk <jason.andryuk@amd.com> > --- > xen/arch/arm/dom0less-build.c | 67 +++++++++++++++++------ > xen/arch/arm/domain_build.c | 2 + > xen/arch/arm/include/asm/dom0less-build.h | 2 + > 3 files changed, 53 insertions(+), 18 deletions(-) > > diff --git a/xen/arch/arm/dom0less-build.c b/xen/arch/arm/dom0less-build.c > index e25d7bd468..a46f292c1f 100644 > --- a/xen/arch/arm/dom0less-build.c > +++ b/xen/arch/arm/dom0less-build.c > @@ -20,6 +20,15 @@ > #include <asm/static-memory.h> > #include <asm/static-shmem.h> > > +static domid_t __initdata xs_domid = DOMID_INVALID; > +static bool __initdata need_xenstore; > + > +void __init set_xs_domain(struct domain *d) > +{ > + xs_domid = d->domain_id; > + set_global_virq_handler(d, VIRQ_DOM_EXC); > +} > + > bool __init is_dom0less_mode(void) > { > struct bootmodules *mods = &bootinfo.modules; > @@ -694,7 +703,7 @@ static int __init alloc_xenstore_evtchn(struct domain *d) > int rc; > > alloc.dom = d->domain_id; > - alloc.remote_dom = hardware_domain->domain_id; > + alloc.remote_dom = xs_domid; > rc = evtchn_alloc_unbound(&alloc, 0); > if ( rc ) > { > @@ -760,16 +769,10 @@ static int __init alloc_xenstore_params(struct kernel_info *kinfo) > struct domain *d = kinfo->d; > int rc = 0; > > - if ( kinfo->dom0less_feature & (DOM0LESS_XENSTORE | DOM0LESS_XS_LEGACY) ) > - { > - ASSERT(hardware_domain); > - rc = alloc_xenstore_evtchn(d); > - if ( rc < 0 ) > - return rc; > + if ( (kinfo->dom0less_feature & (DOM0LESS_XENSTORE | DOM0LESS_XS_LEGACY)) > + == (DOM0LESS_XENSTORE | DOM0LESS_XS_LEGACY) ) > d->arch.hvm.params[HVM_PARAM_STORE_PFN] = ~0ULL; > - } > - > - if ( kinfo->dom0less_feature & DOM0LESS_XENSTORE ) > + else if ( kinfo->dom0less_feature & DOM0LESS_XENSTORE ) > { > rc = alloc_xenstore_page(d); > if ( rc < 0 ) > @@ -841,6 +844,30 @@ static void __init domain_vcpu_affinity(struct domain *d, > } > } > > +static void __init initialize_domU_xenstore(void) > +{ > + struct domain *d; > + > + if ( xs_domid == DOMID_INVALID ) > + return; > + > + for_each_domain( d ) > + { > + unsigned long gfn = d->arch.hvm.params[HVM_PARAM_STORE_PFN]; This should be uint64_t. With that change: Reviewed-by: Stefano Stabellini <sstabellini@kernel.org> > + int rc; > + > + if ( gfn == 0 ) > + continue; > + > + if ( is_xenstore_domain(d) ) > + continue; > + > + rc = alloc_xenstore_evtchn(d); > + if ( rc < 0 ) > + panic("%pd: Failed to allocate xenstore_evtchn\n", d); > + } > +} > + > static int __init construct_domU(struct domain *d, > const struct dt_device_node *node) > {
diff --git a/xen/arch/arm/dom0less-build.c b/xen/arch/arm/dom0less-build.c index e25d7bd468..a46f292c1f 100644 --- a/xen/arch/arm/dom0less-build.c +++ b/xen/arch/arm/dom0less-build.c @@ -20,6 +20,15 @@ #include <asm/static-memory.h> #include <asm/static-shmem.h> +static domid_t __initdata xs_domid = DOMID_INVALID; +static bool __initdata need_xenstore; + +void __init set_xs_domain(struct domain *d) +{ + xs_domid = d->domain_id; + set_global_virq_handler(d, VIRQ_DOM_EXC); +} + bool __init is_dom0less_mode(void) { struct bootmodules *mods = &bootinfo.modules; @@ -694,7 +703,7 @@ static int __init alloc_xenstore_evtchn(struct domain *d) int rc; alloc.dom = d->domain_id; - alloc.remote_dom = hardware_domain->domain_id; + alloc.remote_dom = xs_domid; rc = evtchn_alloc_unbound(&alloc, 0); if ( rc ) { @@ -760,16 +769,10 @@ static int __init alloc_xenstore_params(struct kernel_info *kinfo) struct domain *d = kinfo->d; int rc = 0; - if ( kinfo->dom0less_feature & (DOM0LESS_XENSTORE | DOM0LESS_XS_LEGACY) ) - { - ASSERT(hardware_domain); - rc = alloc_xenstore_evtchn(d); - if ( rc < 0 ) - return rc; + if ( (kinfo->dom0less_feature & (DOM0LESS_XENSTORE | DOM0LESS_XS_LEGACY)) + == (DOM0LESS_XENSTORE | DOM0LESS_XS_LEGACY) ) d->arch.hvm.params[HVM_PARAM_STORE_PFN] = ~0ULL; - } - - if ( kinfo->dom0less_feature & DOM0LESS_XENSTORE ) + else if ( kinfo->dom0less_feature & DOM0LESS_XENSTORE ) { rc = alloc_xenstore_page(d); if ( rc < 0 ) @@ -841,6 +844,30 @@ static void __init domain_vcpu_affinity(struct domain *d, } } +static void __init initialize_domU_xenstore(void) +{ + struct domain *d; + + if ( xs_domid == DOMID_INVALID ) + return; + + for_each_domain( d ) + { + unsigned long gfn = d->arch.hvm.params[HVM_PARAM_STORE_PFN]; + int rc; + + if ( gfn == 0 ) + continue; + + if ( is_xenstore_domain(d) ) + continue; + + rc = alloc_xenstore_evtchn(d); + if ( rc < 0 ) + panic("%pd: Failed to allocate xenstore_evtchn\n", d); + } +} + static int __init construct_domU(struct domain *d, const struct dt_device_node *node) { @@ -881,17 +908,13 @@ static int __init construct_domU(struct domain *d, rc == -ENODATA || (rc == 0 && !strcmp(dom0less_enhanced, "enabled")) ) { - if ( hardware_domain ) - kinfo.dom0less_feature = DOM0LESS_ENHANCED; - else - panic("At the moment, Xenstore support requires dom0 to be present\n"); + need_xenstore = true; + kinfo.dom0less_feature = DOM0LESS_ENHANCED; } else if ( rc == 0 && !strcmp(dom0less_enhanced, "legacy") ) { - if ( hardware_domain ) - kinfo.dom0less_feature = DOM0LESS_ENHANCED_LEGACY; - else - panic("At the moment, Xenstore support requires dom0 to be present\n"); + need_xenstore = true; + kinfo.dom0less_feature = DOM0LESS_ENHANCED_LEGACY; } else if ( rc == 0 && !strcmp(dom0less_enhanced, "no-xenstore") ) kinfo.dom0less_feature = DOM0LESS_ENHANCED_NO_XS; @@ -1138,7 +1161,15 @@ void __init create_domUs(void) if ( rc ) panic("Could not set up domain %s (rc = %d)\n", dt_node_name(node), rc); + + if ( d_cfg.flags & XEN_DOMCTL_CDF_xs_domain ) + set_xs_domain(d); } + + if ( need_xenstore && xs_domid == DOMID_INVALID ) + panic("xenstore requested, but xenstore domain not present\n"); + + initialize_domU_xenstore(); } /* diff --git a/xen/arch/arm/domain_build.c b/xen/arch/arm/domain_build.c index b3a396c2fc..d99ca7b43f 100644 --- a/xen/arch/arm/domain_build.c +++ b/xen/arch/arm/domain_build.c @@ -2408,6 +2408,8 @@ void __init create_dom0(void) rc = construct_dom0(dom0); if ( rc ) panic("Could not set up DOM0 guest OS (rc = %d)\n", rc); + + set_xs_domain(dom0); } /* diff --git a/xen/arch/arm/include/asm/dom0less-build.h b/xen/arch/arm/include/asm/dom0less-build.h index 5864944bda..b0e41a1954 100644 --- a/xen/arch/arm/include/asm/dom0less-build.h +++ b/xen/arch/arm/include/asm/dom0less-build.h @@ -9,6 +9,7 @@ void create_domUs(void); bool is_dom0less_mode(void); +void set_xs_domain(struct domain *d); #else /* !CONFIG_DOM0LESS_BOOT */ @@ -17,6 +18,7 @@ static inline bool is_dom0less_mode(void) { return false; } +static inline void set_xs_domain(struct domain *d) {} #endif /* CONFIG_DOM0LESS_BOOT */