To allocate the xenstore event channel and initialize the grant table entry, the xenstore domid is neeed. A dom0 is craeted 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 and 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. Signed-off-by: Jason Andryuk <jason.andr...@amd.com> --- xen/arch/arm/dom0less-build.c | 71 +++++++++++++++-------- xen/arch/arm/domain_build.c | 1 + xen/arch/arm/include/asm/dom0less-build.h | 2 + 3 files changed, 51 insertions(+), 23 deletions(-) diff --git a/xen/arch/arm/dom0less-build.c b/xen/arch/arm/dom0less-build.c index f1d5bbb097..3b8153b05e 100644 --- a/xen/arch/arm/dom0less-build.c +++ b/xen/arch/arm/dom0less-build.c @@ -22,6 +22,12 @@ #include <asm/static-shmem.h> static domid_t __initdata xs_domid = DOMID_INVALID; +static bool __initdata need_xenstore; + +void __init set_xs_domid(domid_t domid) +{ + xs_domid = domid; +} bool __init is_dom0less_mode(void) { @@ -697,7 +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 ) { @@ -755,10 +761,6 @@ static int __init alloc_xenstore_page(struct domain *d) interface->connection = XENSTORE_RECONNECT; unmap_domain_page(interface); - if ( xs_domid != DOMID_INVALID ) - gnttab_seed_entry(d, GNTTAB_RESERVED_XENSTORE, xs_domid, - gfn_x(gfn), GTF_permit_access); - return 0; } @@ -767,16 +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 ) @@ -848,6 +844,34 @@ 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); + + if ( gfn != ~0ULL ) + gnttab_seed_entry(d, GNTTAB_RESERVED_XENSTORE, xs_domid, + gfn, GTF_permit_access); + } +} + static int __init construct_domU(struct domain *d, const struct dt_device_node *node) { @@ -888,17 +912,13 @@ 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; @@ -1181,8 +1201,13 @@ void __init create_domUs(void) dt_node_name(node), rc); if ( d_cfg.flags & XEN_DOMCTL_CDF_xs_domain ) - xs_domid = d->domain_id; + set_xs_domid(d->domain_id); } + + 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 00bc484642..ba6bbb95c1 100644 --- a/xen/arch/arm/domain_build.c +++ b/xen/arch/arm/domain_build.c @@ -2373,6 +2373,7 @@ void __init create_dom0(void) unsigned int flags = CDF_privileged | CDF_hardware; int rc; + set_xs_domid(0); /* The vGIC for DOM0 is exactly emulating the hardware GIC */ dom0_cfg.arch.gic_version = XEN_DOMCTL_CONFIG_GIC_NATIVE; /* diff --git a/xen/arch/arm/include/asm/dom0less-build.h b/xen/arch/arm/include/asm/dom0less-build.h index 5864944bda..df879f93c8 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_domid(domid_t); #else /* !CONFIG_DOM0LESS_BOOT */ @@ -17,6 +18,7 @@ static inline bool is_dom0less_mode(void) { return false; } +static inline void set_xs_domid(domid_t) {} #endif /* CONFIG_DOM0LESS_BOOT */ -- 2.48.1