On 01/27/15 14:10, Ard Biesheuvel wrote: > On 27 January 2015 at 12:46, Ard Biesheuvel <[email protected]> wrote: >> On 27 January 2015 at 12:43, Stefano Stabellini >> <[email protected]> wrote: >>> On Mon, 26 Jan 2015, Ard Biesheuvel wrote: >>>> This refactors the Xen hypercall implementation that is part of the >>>> XenBusDxe driver, in preparation of splitting it off entirely into >>>> a XenHypercallLib library. This involves: >>>> - removing the dependency on XENBUS_DEVICE* pointers in the XenHypercall() >>>> prototypes >>>> - moving the discovered hyperpage address to a global variable >>>> - moving XenGetSharedInfoPage() to its only user XenBusDxe.c (the shared >>>> info >>>> page is not strictly part of the Xen hypercall interface, and is not used >>>> by other expected users of XenHypercallLib such as the Xen console >>>> version >>>> of SerialPortLib >>>> - reimplement XenHypercall2() in C and move the indexing of the hyperpage >>>> there; the existing asm implementations are renamed to __XenHypercall2() >>>> and >>>> invoked from the new C implementation. >>>> >>>> Contributed-under: TianoCore Contribution Agreement 1.0 >>>> Signed-off-by: Ard Biesheuvel <[email protected]> >>>> --- >>>> OvmfPkg/XenBusDxe/EventChannel.c | 11 +++-------- >>>> OvmfPkg/XenBusDxe/GrantTable.c | 4 ++-- >>>> OvmfPkg/XenBusDxe/Ia32/hypercall.nasm | 6 +++--- >>>> OvmfPkg/XenBusDxe/X64/hypercall.nasm | 6 +++--- >>>> OvmfPkg/XenBusDxe/XenBusDxe.c | 44 >>>> +++++++++++++++++++++++++++++++++++++++++++- >>>> OvmfPkg/XenBusDxe/XenBusDxe.h | 1 - >>>> OvmfPkg/XenBusDxe/XenHypercall.c | 50 >>>> ++++++++++++++------------------------------------ >>>> OvmfPkg/XenBusDxe/XenHypercall.h | 28 +++------------------------- >>>> OvmfPkg/XenBusDxe/XenStore.c | 4 ++-- >>>> 9 files changed, 73 insertions(+), 81 deletions(-) >>>> >>>> diff --git a/OvmfPkg/XenBusDxe/EventChannel.c >>>> b/OvmfPkg/XenBusDxe/EventChannel.c >>>> index 03efaf9cb904..a86323e6adfd 100644 >>>> --- a/OvmfPkg/XenBusDxe/EventChannel.c >>>> +++ b/OvmfPkg/XenBusDxe/EventChannel.c >>>> @@ -28,7 +28,7 @@ XenEventChannelNotify ( >>>> evtchn_send_t Send; >>>> >>>> Send.port = Port; >>>> - ReturnCode = XenHypercallEventChannelOp (Dev, EVTCHNOP_send, &Send); >>>> + ReturnCode = XenHypercallEventChannelOp (EVTCHNOP_send, &Send); >>>> return (UINT32)ReturnCode; >>>> } >>>> >>>> @@ -40,15 +40,12 @@ XenBusEventChannelAllocate ( >>>> OUT evtchn_port_t *Port >>>> ) >>>> { >>>> - XENBUS_PRIVATE_DATA *Private; >>>> evtchn_alloc_unbound_t Parameter; >>>> UINT32 ReturnCode; >>>> >>>> - Private = XENBUS_PRIVATE_DATA_FROM_THIS (This); >>>> - >>>> Parameter.dom = DOMID_SELF; >>>> Parameter.remote_dom = DomainId; >>>> - ReturnCode = (UINT32)XenHypercallEventChannelOp (Private->Dev, >>>> + ReturnCode = (UINT32)XenHypercallEventChannelOp ( >>>> EVTCHNOP_alloc_unbound, >>>> &Parameter); >>>> if (ReturnCode != 0) { >>>> @@ -79,10 +76,8 @@ XenBusEventChannelClose ( >>>> IN evtchn_port_t Port >>>> ) >>>> { >>>> - XENBUS_PRIVATE_DATA *Private; >>>> evtchn_close_t Close; >>>> >>>> - Private = XENBUS_PRIVATE_DATA_FROM_THIS (This); >>>> Close.port = Port; >>>> - return (UINT32)XenHypercallEventChannelOp (Private->Dev, >>>> EVTCHNOP_close, &Close); >>>> + return (UINT32)XenHypercallEventChannelOp (EVTCHNOP_close, &Close); >>>> } >>>> diff --git a/OvmfPkg/XenBusDxe/GrantTable.c >>>> b/OvmfPkg/XenBusDxe/GrantTable.c >>>> index 8405edc51bc4..53cb99f0e004 100644 >>>> --- a/OvmfPkg/XenBusDxe/GrantTable.c >>>> +++ b/OvmfPkg/XenBusDxe/GrantTable.c >>>> @@ -161,7 +161,7 @@ XenGrantTableInit ( >>>> Parameters.idx = Index; >>>> Parameters.space = XENMAPSPACE_grant_table; >>>> Parameters.gpfn = (xen_pfn_t) ((UINTN) GrantTable >> EFI_PAGE_SHIFT) >>>> + Index; >>>> - ReturnCode = XenHypercallMemoryOp (Dev, XENMEM_add_to_physmap, >>>> &Parameters); >>>> + ReturnCode = XenHypercallMemoryOp (XENMEM_add_to_physmap, >>>> &Parameters); >>>> if (ReturnCode != 0) { >>>> DEBUG ((EFI_D_ERROR, "Xen GrantTable, add_to_physmap hypercall >>>> error: %d\n", ReturnCode)); >>>> } >>>> @@ -184,7 +184,7 @@ XenGrantTableDeinit ( >>>> Parameters.domid = DOMID_SELF; >>>> Parameters.gpfn = (xen_pfn_t) ((UINTN) GrantTable >> EFI_PAGE_SHIFT) >>>> + Index; >>>> DEBUG ((EFI_D_INFO, "Xen GrantTable, removing %X\n", >>>> Parameters.gpfn)); >>>> - ReturnCode = XenHypercallMemoryOp (Dev, XENMEM_remove_from_physmap, >>>> &Parameters); >>>> + ReturnCode = XenHypercallMemoryOp (XENMEM_remove_from_physmap, >>>> &Parameters); >>>> if (ReturnCode != 0) { >>>> DEBUG ((EFI_D_ERROR, "Xen GrantTable, remove_from_physmap hypercall >>>> error: %d\n", ReturnCode)); >>>> } >>>> diff --git a/OvmfPkg/XenBusDxe/Ia32/hypercall.nasm >>>> b/OvmfPkg/XenBusDxe/Ia32/hypercall.nasm >>>> index 8547c30b81ee..e0fa71bb5ba8 100644 >>>> --- a/OvmfPkg/XenBusDxe/Ia32/hypercall.nasm >>>> +++ b/OvmfPkg/XenBusDxe/Ia32/hypercall.nasm >>>> @@ -2,13 +2,13 @@ SECTION .text >>>> >>>> ; INTN >>>> ; EFIAPI >>>> -; XenHypercall2 ( >>>> +; __XenHypercall2 ( >>>> ; IN VOID *HypercallAddr, >>>> ; IN OUT INTN Arg1, >>>> ; IN OUT INTN Arg2 >>>> ; ); >>>> -global ASM_PFX(XenHypercall2) >>>> -ASM_PFX(XenHypercall2): >>>> +global ASM_PFX(__XenHypercall2) >>>> +ASM_PFX(__XenHypercall2): >>>> ; Save only ebx, ecx is supposed to be a scratch register and needs to >>>> be >>>> ; saved by the caller >>>> push ebx >>>> diff --git a/OvmfPkg/XenBusDxe/X64/hypercall.nasm >>>> b/OvmfPkg/XenBusDxe/X64/hypercall.nasm >>>> index 177f271ef094..5e6a0c05c5c4 100644 >>>> --- a/OvmfPkg/XenBusDxe/X64/hypercall.nasm >>>> +++ b/OvmfPkg/XenBusDxe/X64/hypercall.nasm >>>> @@ -3,13 +3,13 @@ SECTION .text >>>> >>>> ; INTN >>>> ; EFIAPI >>>> -; XenHypercall2 ( >>>> +; __XenHypercall2 ( >>>> ; IN VOID *HypercallAddr, >>>> ; IN OUT INTN Arg1, >>>> ; IN OUT INTN Arg2 >>>> ; ); >>>> -global ASM_PFX(XenHypercall2) >>>> -ASM_PFX(XenHypercall2): >>>> +global ASM_PFX(__XenHypercall2) >>>> +ASM_PFX(__XenHypercall2): >>>> push rdi >>>> push rsi >>>> ; Copy HypercallAddr to rax >>>> diff --git a/OvmfPkg/XenBusDxe/XenBusDxe.c b/OvmfPkg/XenBusDxe/XenBusDxe.c >>>> index 7a7fd82d559d..d333b331b6db 100644 >>>> --- a/OvmfPkg/XenBusDxe/XenBusDxe.c >>>> +++ b/OvmfPkg/XenBusDxe/XenBusDxe.c >>>> @@ -34,6 +34,8 @@ >>>> #include "XenStore.h" >>>> #include "XenBus.h" >>>> >>>> +#include <IndustryStandard/Xen/hvm/params.h> >>>> +#include <IndustryStandard/Xen/memory.h> >>>> >>>> /// >>>> /// Driver Binding Protocol instance >>>> @@ -52,6 +54,46 @@ STATIC EFI_LOCK mMyDeviceLock = >>>> EFI_INITIALIZE_LOCK_VARIABLE (TPL_CALLBACK >>>> STATIC XENBUS_DEVICE *mMyDevice = NULL; >>>> >>>> /** >>>> + Map the shared_info_t page into memory. >>>> + >>>> + @param Dev A XENBUS_DEVICE instance. >>>> + >>>> + @retval EFI_SUCCESS Dev->SharedInfo whill contain a pointer to >>>> + the shared info page >>>> + @retval EFI_LOAD_ERROR The shared info page could not be mapped. The >>>> + hypercall returned an error. >>>> +**/ >>>> +STATIC >>>> +EFI_STATUS >>>> +XenGetSharedInfoPage ( >>>> + IN OUT XENBUS_DEVICE *Dev >>>> + ) >>>> +{ >>>> + xen_add_to_physmap_t Parameter; >>>> + >>>> + ASSERT (Dev->SharedInfo == NULL); >>>> + >>>> + Parameter.domid = DOMID_SELF; >>>> + Parameter.space = XENMAPSPACE_shared_info; >>>> + Parameter.idx = 0; >>>> + >>>> + // >>>> + // using reserved page because the page is not released when Linux is >>>> + // starting because of the add_to_physmap. QEMU might try to access the >>>> + // page, and fail because it have no right to do so (segv). >>>> + // >>>> + Dev->SharedInfo = AllocateReservedPages (1); >>>> + Parameter.gpfn = (UINTN) Dev->SharedInfo >> EFI_PAGE_SHIFT; >>>> + if (XenHypercallMemoryOp (XENMEM_add_to_physmap, &Parameter) != 0) { >>>> + FreePages (Dev->SharedInfo, 1); >>>> + Dev->SharedInfo = NULL; >>>> + return EFI_LOAD_ERROR; >>>> + } >>>> + >>>> + return EFI_SUCCESS; >>>> +} >>>> + >>>> +/** >>>> Unloads an image. >>>> >>>> @param ImageHandle Handle that identifies the image to be >>>> unloaded. >>>> @@ -348,7 +390,7 @@ XenBusDxeDriverBindingStart ( >>>> MmioAddr = BarDesc->AddrRangeMin; >>>> FreePool (BarDesc); >>>> >>>> - Status = XenHyperpageInit (Dev); >>>> + Status = XenHyperpageInit (); >>>> if (EFI_ERROR (Status)) { >>>> DEBUG ((EFI_D_ERROR, "XenBus: Unable to retrieve the hyperpage.\n")); >>>> Status = EFI_UNSUPPORTED; >>>> diff --git a/OvmfPkg/XenBusDxe/XenBusDxe.h b/OvmfPkg/XenBusDxe/XenBusDxe.h >>>> index 80253b7d1ca9..9b7219906a69 100644 >>>> --- a/OvmfPkg/XenBusDxe/XenBusDxe.h >>>> +++ b/OvmfPkg/XenBusDxe/XenBusDxe.h >>>> @@ -91,7 +91,6 @@ struct _XENBUS_DEVICE { >>>> EFI_DEVICE_PATH_PROTOCOL *DevicePath; >>>> LIST_ENTRY ChildList; >>>> >>>> - VOID *Hyperpage; >>>> shared_info_t *SharedInfo; >>>> }; >>>> >>>> diff --git a/OvmfPkg/XenBusDxe/XenHypercall.c >>>> b/OvmfPkg/XenBusDxe/XenHypercall.c >>>> index 34d92e76b7e3..9bcf3197633e 100644 >>>> --- a/OvmfPkg/XenBusDxe/XenHypercall.c >>>> +++ b/OvmfPkg/XenBusDxe/XenHypercall.c >>>> @@ -23,9 +23,10 @@ >>>> #include <IndustryStandard/Xen/hvm/params.h> >>>> #include <IndustryStandard/Xen/memory.h> >>>> >>>> +STATIC VOID *Hyperpage; >>>> + >>>> EFI_STATUS >>>> XenHyperpageInit ( >>>> - IN OUT XENBUS_DEVICE *Dev >>>> ) >>>> { >>>> EFI_HOB_GUID_TYPE *GuidHob; >>>> @@ -36,24 +37,21 @@ XenHyperpageInit ( >>>> return EFI_NOT_FOUND; >>>> } >>>> XenInfo = (EFI_XEN_INFO *) GET_GUID_HOB_DATA (GuidHob); >>>> - Dev->Hyperpage = XenInfo->HyperPages; >>>> + Hyperpage = XenInfo->HyperPages; >>>> return EFI_SUCCESS; >>>> } >>>> >>>> UINT64 >>>> XenHypercallHvmGetParam ( >>>> - IN XENBUS_DEVICE *Dev, >>>> IN UINT32 Index >>>> ) >>>> { >>>> xen_hvm_param_t Parameter; >>>> INTN Error; >>>> >>>> - ASSERT (Dev->Hyperpage != NULL); >>>> - >>>> Parameter.domid = DOMID_SELF; >>>> Parameter.index = Index; >>>> - Error = XenHypercall2 ((UINT8*)Dev->Hyperpage + __HYPERVISOR_hvm_op * >>>> 32, >>>> + Error = XenHypercall2 (__HYPERVISOR_hvm_op, >>>> HVMOP_get_param, (INTN) &Parameter); >>>> if (Error != 0) { >>>> DEBUG ((EFI_D_ERROR, >>>> @@ -66,53 +64,33 @@ XenHypercallHvmGetParam ( >>>> >>>> INTN >>>> XenHypercallMemoryOp ( >>>> - IN XENBUS_DEVICE *Dev, >>>> IN UINTN Operation, >>>> IN OUT VOID *Arguments >>>> ) >>>> { >>>> - ASSERT (Dev->Hyperpage != NULL); >>>> - return XenHypercall2 ((UINT8*)Dev->Hyperpage + __HYPERVISOR_memory_op * >>>> 32, >>>> + return XenHypercall2 (__HYPERVISOR_memory_op, >>>> Operation, (INTN) Arguments); >>>> } >>>> >>>> INTN >>>> XenHypercallEventChannelOp ( >>>> - IN XENBUS_DEVICE *Dev, >>>> IN INTN Operation, >>>> IN OUT VOID *Arguments >>>> ) >>>> { >>>> - ASSERT (Dev->Hyperpage != NULL); >>>> - return XenHypercall2 ((UINT8*)Dev->Hyperpage + >>>> __HYPERVISOR_event_channel_op * 32, >>>> + return XenHypercall2 (__HYPERVISOR_event_channel_op, >>>> Operation, (INTN) Arguments); >>>> } >>>> >>>> -EFI_STATUS >>>> -XenGetSharedInfoPage ( >>>> - IN OUT XENBUS_DEVICE *Dev >>>> +INTN >>>> +EFIAPI >>>> +XenHypercall2 ( >>>> + IN INTN HypercallID, >>>> + IN OUT INTN Arg1, >>>> + IN OUT INTN Arg2 >>>> ) >>>> { >>>> - xen_add_to_physmap_t Parameter; >>>> - >>>> - ASSERT (Dev->SharedInfo == NULL); >>>> + ASSERT (HyperPage != NULL); >>>> >>>> - Parameter.domid = DOMID_SELF; >>>> - Parameter.space = XENMAPSPACE_shared_info; >>>> - Parameter.idx = 0; >>>> - >>>> - // >>>> - // using reserved page because the page is not released when Linux is >>>> - // starting because of the add_to_physmap. QEMU might try to access the >>>> - // page, and fail because it have no right to do so (segv). >>>> - // >>>> - Dev->SharedInfo = AllocateReservedPages (1); >>>> - Parameter.gpfn = (UINTN) Dev->SharedInfo >> EFI_PAGE_SHIFT; >>>> - if (XenHypercallMemoryOp (Dev, XENMEM_add_to_physmap, &Parameter) != 0) >>>> { >>>> - FreePages (Dev->SharedInfo, 1); >>>> - Dev->SharedInfo = NULL; >>>> - return EFI_LOAD_ERROR; >>>> - } >>>> - >>>> - return EFI_SUCCESS; >>>> + return __XenHypercall2 ((UINT8*)HyperPage + HypercallID * 32, Arg1, >>>> Arg2); >>> ^ shouldn't it be Hyperpage? >>> >> >> Yes, you are quite right. My build test on x86 should have spotted >> this, so apparently I screwed that up in some way as well. >> > > Turns out this was a refactoring error that got cleaned up by the next > patch, and I did not perform the x86 build test on each patch in > isolation. > Will be fixed in v3 >
I skimmed this patch. It makes sense to me as preparation for librarizing the hypercall machinery (as you say in the commit message), if the Xen guys don't have any objections. I peeked forward at patch 18. The librarization is certainly possible given that the origin of your info is the GUID HOB with gEfiXenInfoGuid. So, I got curious about the data pointed-to by the gEfiXenInfoGuid HOB... It's set up in OvmfPkg/PlatformPei/Xen.c. I froze for a second, but then I noticed it uses BuildGuidDataHob(), *not* BuildGuidHob(); ie. it *copies* mXenInfo into the HOB. Good. I think this patch (and the next one) improve OVMF/Xen even in isolation (== without thinking of ARM at all). For v3: Acked-by: Laszlo Ersek <[email protected]> Thanks Laszlo ------------------------------------------------------------------------------ Dive into the World of Parallel Programming. The Go Parallel Website, sponsored by Intel and developed in partnership with Slashdot Media, is your hub for all things parallel software development, from weekly thought leadership blogs to news, videos, case studies, tutorials and more. Take a look and join the conversation now. http://goparallel.sourceforge.net/ _______________________________________________ edk2-devel mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/edk2-devel
