linux-sg2042/include/xen/xen.h

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#ifndef _XEN_XEN_H
#define _XEN_XEN_H
enum xen_domain_type {
XEN_NATIVE, /* running on bare hardware */
XEN_PV_DOMAIN, /* running in a PV domain */
XEN_HVM_DOMAIN, /* running in a Xen hvm domain */
};
#ifdef CONFIG_XEN
extern enum xen_domain_type xen_domain_type;
#else
#define xen_domain_type XEN_NATIVE
#endif
#define xen_domain() (xen_domain_type != XEN_NATIVE)
#define xen_pv_domain() (xen_domain() && \
xen_domain_type == XEN_PV_DOMAIN)
#define xen_hvm_domain() (xen_domain() && \
xen_domain_type == XEN_HVM_DOMAIN)
#ifdef CONFIG_XEN_DOM0
#include <xen/interface/xen.h>
#include <asm/xen/hypervisor.h>
#define xen_initial_domain() (xen_domain() && \
xen_start_info && xen_start_info->flags & SIF_INITDOMAIN)
#else /* !CONFIG_XEN_DOM0 */
#define xen_initial_domain() (0)
#endif /* CONFIG_XEN_DOM0 */
xen/pvh/x86: Define what an PVH guest is (v3). Which is a PV guest with auto page translation enabled and with vector callback. It is a cross between PVHVM and PV. The Xen side defines PVH as (from docs/misc/pvh-readme.txt, with modifications): "* the guest uses auto translate: - p2m is managed by Xen - pagetables are owned by the guest - mmu_update hypercall not available * it uses event callback and not vlapic emulation, * IDT is native, so set_trap_table hcall is also N/A for a PVH guest. For a full list of hcalls supported for PVH, see pvh_hypercall64_table in arch/x86/hvm/hvm.c in xen. From the ABI prespective, it's mostly a PV guest with auto translate, although it does use hvm_op for setting callback vector." Also we use the PV cpuid, albeit we can use the HVM (native) cpuid. However, we do have a fair bit of filtering in the xen_cpuid and we can piggyback on that until the hypervisor/toolstack filters the appropiate cpuids. Once that is done we can swap over to use the native one. We setup a Kconfig entry that is disabled by default and cannot be enabled. Note that on ARM the concept of PVH is non-existent. As Ian put it: "an ARM guest is neither PV nor HVM nor PVHVM. It's a bit like PVH but is different also (it's further towards the H end of the spectrum than even PVH).". As such these options (PVHVM, PVH) are never enabled nor seen on ARM compilations. Signed-off-by: Mukesh Rathor <mukesh.rathor@oracle.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2013-12-14 01:39:56 +08:00
#ifdef CONFIG_XEN_PVH
/* This functionality exists only for x86. The XEN_PVHVM support exists
* only in x86 world - hence on ARM it will be always disabled.
* N.B. ARM guests are neither PV nor HVM nor PVHVM.
* It's a bit like PVH but is different also (it's further towards the H
* end of the spectrum than even PVH).
*/
#include <xen/features.h>
#define xen_pvh_domain() (xen_pv_domain() && \
xen: Remove event channel notification through Xen PCI platform device Ever since commit 254d1a3f02eb ("xen/pv-on-hvm kexec: shutdown watches from old kernel") using the INTx interrupt from Xen PCI platform device for event channel notification would just lockup the guest during bootup. postcore_initcall now calls xs_reset_watches which will eventually try to read a value from XenStore and will get stuck on read_reply at XenBus forever since the platform driver is not probed yet and its INTx interrupt handler is not registered yet. That means that the guest can not be notified at this moment of any pending event channels and none of the per-event handlers will ever be invoked (including the XenStore one) and the reply will never be picked up by the kernel. The exact stack where things get stuck during xenbus_init: -xenbus_init -xs_init -xs_reset_watches -xenbus_scanf -xenbus_read -xs_single -xs_single -xs_talkv Vector callbacks have always been the favourite event notification mechanism since their introduction in commit 38e20b07efd5 ("x86/xen: event channels delivery on HVM.") and the vector callback feature has always been advertised for quite some time by Xen that's why INTx was broken for several years now without impacting anyone. Luckily this also means that event channel notification through INTx is basically dead-code which can be safely removed without impacting anybody since it has been effectively disabled for more than 4 years with nobody complaining about it (at least as far as I'm aware of). This commit removes event channel notification through Xen PCI platform device. Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: David Vrabel <david.vrabel@citrix.com> Cc: Juergen Gross <jgross@suse.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: x86@kernel.org Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Cc: Julien Grall <julien.grall@citrix.com> Cc: Vitaly Kuznetsov <vkuznets@redhat.com> Cc: Paul Gortmaker <paul.gortmaker@windriver.com> Cc: Ross Lagerwall <ross.lagerwall@citrix.com> Cc: xen-devel@lists.xenproject.org Cc: linux-kernel@vger.kernel.org Cc: linux-pci@vger.kernel.org Cc: Anthony Liguori <aliguori@amazon.com> Signed-off-by: KarimAllah Ahmed <karahmed@amazon.de> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2016-08-27 05:55:36 +08:00
xen_feature(XENFEAT_auto_translated_physmap))
xen/pvh/x86: Define what an PVH guest is (v3). Which is a PV guest with auto page translation enabled and with vector callback. It is a cross between PVHVM and PV. The Xen side defines PVH as (from docs/misc/pvh-readme.txt, with modifications): "* the guest uses auto translate: - p2m is managed by Xen - pagetables are owned by the guest - mmu_update hypercall not available * it uses event callback and not vlapic emulation, * IDT is native, so set_trap_table hcall is also N/A for a PVH guest. For a full list of hcalls supported for PVH, see pvh_hypercall64_table in arch/x86/hvm/hvm.c in xen. From the ABI prespective, it's mostly a PV guest with auto translate, although it does use hvm_op for setting callback vector." Also we use the PV cpuid, albeit we can use the HVM (native) cpuid. However, we do have a fair bit of filtering in the xen_cpuid and we can piggyback on that until the hypervisor/toolstack filters the appropiate cpuids. Once that is done we can swap over to use the native one. We setup a Kconfig entry that is disabled by default and cannot be enabled. Note that on ARM the concept of PVH is non-existent. As Ian put it: "an ARM guest is neither PV nor HVM nor PVHVM. It's a bit like PVH but is different also (it's further towards the H end of the spectrum than even PVH).". As such these options (PVHVM, PVH) are never enabled nor seen on ARM compilations. Signed-off-by: Mukesh Rathor <mukesh.rathor@oracle.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2013-12-14 01:39:56 +08:00
#else
#define xen_pvh_domain() (0)
#endif
#endif /* _XEN_XEN_H */