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/* $Id: HGSMIBase.cpp $ */
/** @file
* VirtualBox Video driver, common code - HGSMI initialisation and helper
* functions.
*/
/*
* Copyright (C) 2006-2012 Oracle Corporation
*
* This file is part of VirtualBox Open Source Edition (OSE), as
* available from http://www.virtualbox.org. This file is free software;
* you can redistribute it and/or modify it under the terms of the GNU
* General Public License (GPL) as published by the Free Software
* Foundation, in version 2 as it comes in the "COPYING" file of the
* VirtualBox OSE distribution. VirtualBox OSE is distributed in the
* hope that it will be useful, but WITHOUT ANY WARRANTY of any kind.
*/
#include <VBox/VBoxVideoGuest.h>
#include <VBox/VBoxVideo.h>
#include <VBox/VBoxGuest.h>
#include <VBox/Hardware/VBoxVideoVBE.h>
#include <VBox/VMMDev.h>
#include <iprt/asm.h>
#include <iprt/log.h>
#include <iprt/string.h>
/** Send completion notification to the host for the command located at offset
* @a offt into the host command buffer. */
static void HGSMINotifyHostCmdComplete(PHGSMIHOSTCOMMANDCONTEXT pCtx, HGSMIOFFSET offt)
{
VBoxVideoCmnPortWriteUlong(pCtx->port, offt);
}
/**
* Inform the host that a command has been handled.
*
* @param pCtx the context containing the heap to be used
* @param pvMem pointer into the heap as mapped in @a pCtx to the command to
* be completed
*/
RTDECL(void) VBoxHGSMIHostCmdComplete(PHGSMIHOSTCOMMANDCONTEXT pCtx,
void *pvMem)
{
HGSMIBUFFERHEADER *pHdr = HGSMIBufferHeaderFromData(pvMem);
HGSMIOFFSET offMem = HGSMIPointerToOffset(&pCtx->areaCtx, pHdr);
Assert(offMem != HGSMIOFFSET_VOID);
if(offMem != HGSMIOFFSET_VOID)
{
HGSMINotifyHostCmdComplete(pCtx, offMem);
}
}
/** Submit an incoming host command to the appropriate handler. */
static void hgsmiHostCmdProcess(PHGSMIHOSTCOMMANDCONTEXT pCtx,
HGSMIOFFSET offBuffer)
{
int rc = HGSMIBufferProcess(&pCtx->areaCtx, &pCtx->channels, offBuffer);
Assert(!RT_FAILURE(rc));
if(RT_FAILURE(rc))
{
/* failure means the command was not submitted to the handler for some reason
* it's our responsibility to notify its completion in this case */
HGSMINotifyHostCmdComplete(pCtx, offBuffer);
}
/* if the cmd succeeded it's responsibility of the callback to complete it */
}
/** Get the next command from the host. */
static HGSMIOFFSET hgsmiGetHostBuffer(PHGSMIHOSTCOMMANDCONTEXT pCtx)
{
return VBoxVideoCmnPortReadUlong(pCtx->port);
}
/** Get and handle the next command from the host. */
static void hgsmiHostCommandQueryProcess(PHGSMIHOSTCOMMANDCONTEXT pCtx)
{
HGSMIOFFSET offset = hgsmiGetHostBuffer(pCtx);
AssertReturnVoid(offset != HGSMIOFFSET_VOID);
hgsmiHostCmdProcess(pCtx, offset);
}
/** Drain the host command queue. */
RTDECL(void) VBoxHGSMIProcessHostQueue(PHGSMIHOSTCOMMANDCONTEXT pCtx)
{
while (pCtx->pfHostFlags->u32HostFlags & HGSMIHOSTFLAGS_COMMANDS_PENDING)
{
if (!ASMAtomicCmpXchgBool(&pCtx->fHostCmdProcessing, true, false))
return;
hgsmiHostCommandQueryProcess(pCtx);
ASMAtomicWriteBool(&pCtx->fHostCmdProcessing, false);
}
}
/** Detect whether HGSMI is supported by the host. */
RTDECL(bool) VBoxHGSMIIsSupported(void)
{
uint16_t DispiId;
VBoxVideoCmnPortWriteUshort(VBE_DISPI_IOPORT_INDEX, VBE_DISPI_INDEX_ID);
VBoxVideoCmnPortWriteUshort(VBE_DISPI_IOPORT_DATA, VBE_DISPI_ID_HGSMI);
DispiId = VBoxVideoCmnPortReadUshort(VBE_DISPI_IOPORT_DATA);
return (DispiId == VBE_DISPI_ID_HGSMI);
}
/**
* Allocate and initialise a command descriptor in the guest heap for a
* guest-to-host command.
*
* @returns pointer to the descriptor's command data buffer
* @param pCtx the context containing the heap to be used
* @param cbData the size of the command data to go into the descriptor
* @param u8Ch the HGSMI channel to be used, set to the descriptor
* @param u16Op the HGSMI command to be sent, set to the descriptor
*/
RTDECL(void *) VBoxHGSMIBufferAlloc(PHGSMIGUESTCOMMANDCONTEXT pCtx,
HGSMISIZE cbData,
uint8_t u8Ch,
uint16_t u16Op)
{
#ifdef VBOX_WDDM_MINIPORT
return VBoxSHGSMIHeapAlloc (&pCtx->heapCtx, cbData, u8Ch, u16Op);
#else
return HGSMIHeapAlloc (&pCtx->heapCtx, cbData, u8Ch, u16Op);
#endif
}
/**
* Free a descriptor allocated by @a VBoxHGSMIBufferAlloc.
*
* @param pCtx the context containing the heap used
* @param pvBuffer the pointer returned by @a VBoxHGSMIBufferAlloc
*/
RTDECL(void) VBoxHGSMIBufferFree(PHGSMIGUESTCOMMANDCONTEXT pCtx,
void *pvBuffer)
{
#ifdef VBOX_WDDM_MINIPORT
VBoxSHGSMIHeapFree (&pCtx->heapCtx, pvBuffer);
#else
HGSMIHeapFree (&pCtx->heapCtx, pvBuffer);
#endif
}
/**
* Submit a command descriptor allocated by @a VBoxHGSMIBufferAlloc.
*
* @param pCtx the context containing the heap used
* @param pvBuffer the pointer returned by @a VBoxHGSMIBufferAlloc
*/
RTDECL(int) VBoxHGSMIBufferSubmit(PHGSMIGUESTCOMMANDCONTEXT pCtx,
void *pvBuffer)
{
/* Initialize the buffer and get the offset for port IO. */
HGSMIOFFSET offBuffer = HGSMIHeapBufferOffset (HGSMIGUESTCMDHEAP_GET(&pCtx->heapCtx), pvBuffer);
Assert(offBuffer != HGSMIOFFSET_VOID);
if (offBuffer != HGSMIOFFSET_VOID)
{
/* Submit the buffer to the host. */
VBoxVideoCmnPortWriteUlong(pCtx->port, offBuffer);
return VINF_SUCCESS;
}
return VERR_INVALID_PARAMETER;
}
/** Inform the host of the location of the host flags in VRAM via an HGSMI
* command. */
static int vboxHGSMIReportFlagsLocation(PHGSMIGUESTCOMMANDCONTEXT pCtx,
HGSMIOFFSET offLocation)
{
HGSMIBUFFERLOCATION *p;
int rc = VINF_SUCCESS;
/* Allocate the IO buffer. */
p = (HGSMIBUFFERLOCATION *)VBoxHGSMIBufferAlloc(pCtx,
sizeof(HGSMIBUFFERLOCATION),
HGSMI_CH_HGSMI,
HGSMI_CC_HOST_FLAGS_LOCATION);
if (p)
{
/* Prepare data to be sent to the host. */
p->offLocation = offLocation;
p->cbLocation = sizeof(HGSMIHOSTFLAGS);
rc = VBoxHGSMIBufferSubmit(pCtx, p);
/* Free the IO buffer. */
VBoxHGSMIBufferFree(pCtx, p);
}
else
rc = VERR_NO_MEMORY;
return rc;
}
/** Notify the host of HGSMI-related guest capabilities via an HGSMI command.
*/
static int vboxHGSMISendCapsInfo(PHGSMIGUESTCOMMANDCONTEXT pCtx,
uint32_t fCaps)
{
VBVACAPS *pCaps;
int rc = VINF_SUCCESS;
/* Allocate the IO buffer. */
pCaps = (VBVACAPS *)VBoxHGSMIBufferAlloc(pCtx,
sizeof(VBVACAPS), HGSMI_CH_VBVA,
VBVA_INFO_CAPS);
if (pCaps)
{
/* Prepare data to be sent to the host. */
pCaps->rc = VERR_NOT_IMPLEMENTED;
pCaps->fCaps = fCaps;
rc = VBoxHGSMIBufferSubmit(pCtx, pCaps);
if (RT_SUCCESS(rc))
{
AssertRC(pCaps->rc);
rc = pCaps->rc;
}
/* Free the IO buffer. */
VBoxHGSMIBufferFree(pCtx, pCaps);
}
else
rc = VERR_NO_MEMORY;
return rc;
}
/** Tell the host about the location of the area of VRAM set aside for the host
* heap. */
static int vboxHGSMIReportHostArea(PHGSMIGUESTCOMMANDCONTEXT pCtx,
uint32_t u32AreaOffset, uint32_t u32AreaSize)
{
VBVAINFOHEAP *p;
int rc = VINF_SUCCESS;
/* Allocate the IO buffer. */
p = (VBVAINFOHEAP *)VBoxHGSMIBufferAlloc(pCtx,
sizeof (VBVAINFOHEAP), HGSMI_CH_VBVA,
VBVA_INFO_HEAP);
if (p)
{
/* Prepare data to be sent to the host. */
p->u32HeapOffset = u32AreaOffset;
p->u32HeapSize = u32AreaSize;
rc = VBoxHGSMIBufferSubmit(pCtx, p);
/* Free the IO buffer. */
VBoxHGSMIBufferFree(pCtx, p);
}
else
rc = VERR_NO_MEMORY;
return rc;
}
/**
* Get the information needed to map the basic communication structures in
* device memory into our address space. All pointer parameters are optional.
*
* @param cbVRAM how much video RAM is allocated to the device
* @param poffVRAMBaseMapping where to save the offset from the start of the
* device VRAM of the whole area to map
* @param pcbMapping where to save the mapping size
* @param poffGuestHeapMemory where to save the offset into the mapped area
* of the guest heap backing memory
* @param pcbGuestHeapMemory where to save the size of the guest heap
* backing memory
* @param poffHostFlags where to save the offset into the mapped area
* of the host flags
*/
RTDECL(void) VBoxHGSMIGetBaseMappingInfo(uint32_t cbVRAM,
uint32_t *poffVRAMBaseMapping,
uint32_t *pcbMapping,
uint32_t *poffGuestHeapMemory,
uint32_t *pcbGuestHeapMemory,
uint32_t *poffHostFlags)
{
AssertPtrNullReturnVoid(poffVRAMBaseMapping);
AssertPtrNullReturnVoid(pcbMapping);
AssertPtrNullReturnVoid(poffGuestHeapMemory);
AssertPtrNullReturnVoid(pcbGuestHeapMemory);
AssertPtrNullReturnVoid(poffHostFlags);
if (poffVRAMBaseMapping)
*poffVRAMBaseMapping = cbVRAM - VBVA_ADAPTER_INFORMATION_SIZE;
if (pcbMapping)
*pcbMapping = VBVA_ADAPTER_INFORMATION_SIZE;
if (poffGuestHeapMemory)
*poffGuestHeapMemory = 0;
if (pcbGuestHeapMemory)
*pcbGuestHeapMemory = VBVA_ADAPTER_INFORMATION_SIZE
- sizeof(HGSMIHOSTFLAGS);
if (poffHostFlags)
*poffHostFlags = VBVA_ADAPTER_INFORMATION_SIZE
- sizeof(HGSMIHOSTFLAGS);
}
/**
* Set up the HGSMI guest-to-host command context.
* @returns iprt status value
* @param pCtx the context to set up
* @param pvGuestHeapMemory a pointer to the mapped backing memory for
* the guest heap
* @param cbGuestHeapMemory the size of the backing memory area
* @param offVRAMGuestHeapMemory the offset of the memory pointed to by
* @a pvGuestHeapMemory within the video RAM
*/
RTDECL(int) VBoxHGSMISetupGuestContext(PHGSMIGUESTCOMMANDCONTEXT pCtx,
void *pvGuestHeapMemory,
uint32_t cbGuestHeapMemory,
uint32_t offVRAMGuestHeapMemory)
{
/** @todo should we be using a fixed ISA port value here? */
pCtx->port = (RTIOPORT)VGA_PORT_HGSMI_GUEST;
#ifdef VBOX_WDDM_MINIPORT
return VBoxSHGSMIInit(&pCtx->heapCtx, pvGuestHeapMemory,
cbGuestHeapMemory, offVRAMGuestHeapMemory,
false /*fOffsetBased*/);
#else
return HGSMIHeapSetup(&pCtx->heapCtx, pvGuestHeapMemory,
cbGuestHeapMemory, offVRAMGuestHeapMemory,
false /*fOffsetBased*/);
#endif
}
/**
* Get the information needed to map the area used by the host to send back
* requests.
*
* @param pCtx the context containing the heap to use
* @param cbVRAM how much video RAM is allocated to the device
* @param offVRAMBaseMapping the offset of the basic communication structures
* into the guest's VRAM
* @param poffVRAMHostArea where to store the offset into VRAM of the host
* heap area
* @param pcbHostArea where to store the size of the host heap area
*/
RTDECL(void) VBoxHGSMIGetHostAreaMapping(PHGSMIGUESTCOMMANDCONTEXT pCtx,
uint32_t cbVRAM,
uint32_t offVRAMBaseMapping,
uint32_t *poffVRAMHostArea,
uint32_t *pcbHostArea)
{
uint32_t offVRAMHostArea = offVRAMBaseMapping, cbHostArea = 0;
AssertPtrReturnVoid(poffVRAMHostArea);
AssertPtrReturnVoid(pcbHostArea);
VBoxQueryConfHGSMI(pCtx, VBOX_VBVA_CONF32_HOST_HEAP_SIZE, &cbHostArea);
if (cbHostArea != 0)
{
uint32_t cbHostAreaMaxSize = cbVRAM / 4;
/** @todo what is the idea of this? */
if (cbHostAreaMaxSize >= VBVA_ADAPTER_INFORMATION_SIZE)
{
cbHostAreaMaxSize -= VBVA_ADAPTER_INFORMATION_SIZE;
}
if (cbHostArea > cbHostAreaMaxSize)
{
cbHostArea = cbHostAreaMaxSize;
}
/* Round up to 4096 bytes. */
cbHostArea = (cbHostArea + 0xFFF) & ~0xFFF;
offVRAMHostArea = offVRAMBaseMapping - cbHostArea;
}
*pcbHostArea = cbHostArea;
*poffVRAMHostArea = offVRAMHostArea;
LogFunc(("offVRAMHostArea = 0x%08X, cbHostArea = 0x%08X\n",
offVRAMHostArea, cbHostArea));
}
/**
* Initialise the host context structure.
*
* @param pCtx the context structure to initialise
* @param pvBaseMapping where the basic HGSMI structures are mapped at
* @param offHostFlags the offset of the host flags into the basic HGSMI
* structures
* @param pvHostAreaMapping where the area for the host heap is mapped at
* @param offVRAMHostArea offset of the host heap area into VRAM
* @param cbHostArea size in bytes of the host heap area
*/
RTDECL(void) VBoxHGSMISetupHostContext(PHGSMIHOSTCOMMANDCONTEXT pCtx,
void *pvBaseMapping,
uint32_t offHostFlags,
void *pvHostAreaMapping,
uint32_t offVRAMHostArea,
uint32_t cbHostArea)
{
uint8_t *pu8HostFlags = ((uint8_t *)pvBaseMapping) + offHostFlags;
pCtx->pfHostFlags = (HGSMIHOSTFLAGS *)pu8HostFlags;
/** @todo should we really be using a fixed ISA port value here? */
pCtx->port = (RTIOPORT)VGA_PORT_HGSMI_HOST;
HGSMIAreaInitialize(&pCtx->areaCtx, pvHostAreaMapping, cbHostArea,
offVRAMHostArea);
}
/**
* Tell the host about the ways it can use to communicate back to us via an
* HGSMI command
*
* @returns iprt status value
* @param pCtx the context containing the heap to use
* @param offVRAMFlagsLocation where we wish the host to place its flags
* relative to the start of the VRAM
* @param fCaps additions HGSMI capabilities the guest
* supports
* @param offVRAMHostArea offset into VRAM of the host heap area
* @param cbHostArea size in bytes of the host heap area
*/
RTDECL(int) VBoxHGSMISendHostCtxInfo(PHGSMIGUESTCOMMANDCONTEXT pCtx,
HGSMIOFFSET offVRAMFlagsLocation,
uint32_t fCaps,
uint32_t offVRAMHostArea,
uint32_t cbHostArea)
{
Log(("VBoxVideo::vboxSetupAdapterInfo\n"));
/* setup the flags first to ensure they are initialized by the time the
* host heap is ready */
int rc = vboxHGSMIReportFlagsLocation(pCtx, offVRAMFlagsLocation);
AssertRC(rc);
if (RT_SUCCESS(rc) && fCaps)
{
/* Inform about caps */
rc = vboxHGSMISendCapsInfo(pCtx, fCaps);
AssertRC(rc);
}
if (RT_SUCCESS (rc))
{
/* Report the host heap location. */
rc = vboxHGSMIReportHostArea(pCtx, offVRAMHostArea, cbHostArea);
AssertRC(rc);
}
Log(("VBoxVideo::vboxSetupAdapterInfo finished rc = %d\n", rc));
return rc;
}
/**
* Query the host for an HGSMI configuration parameter via an HGSMI command.
* @returns iprt status value
* @param pCtx the context containing the heap used
* @param u32Index the index of the parameter to query,
* @see VBVACONF32::u32Index
* @param pulValue where to store the value of the parameter on success
*/
RTDECL(int) VBoxQueryConfHGSMI(PHGSMIGUESTCOMMANDCONTEXT pCtx,
uint32_t u32Index, uint32_t *pulValue)
{
int rc = VINF_SUCCESS;
VBVACONF32 *p;
LogFunc(("u32Index = %d\n", u32Index));
/* Allocate the IO buffer. */
p = (VBVACONF32 *)VBoxHGSMIBufferAlloc(pCtx,
sizeof(VBVACONF32), HGSMI_CH_VBVA,
VBVA_QUERY_CONF32);
if (p)
{
/* Prepare data to be sent to the host. */
p->u32Index = u32Index;
p->u32Value = 0;
rc = VBoxHGSMIBufferSubmit(pCtx, p);
if (RT_SUCCESS(rc))
{
*pulValue = p->u32Value;
LogFunc(("u32Value = %d\n", p->u32Value));
}
/* Free the IO buffer. */
VBoxHGSMIBufferFree(pCtx, p);
}
else
rc = VERR_NO_MEMORY;
LogFunc(("rc = %d\n", rc));
return rc;
}
/**
* Pass the host a new mouse pointer shape via an HGSMI command.
*
* @returns success or failure
* @todo why not return an iprt status code?
* @param fFlags cursor flags, @see VMMDevReqMousePointer::fFlags
* @param cHotX horizontal position of the hot spot
* @param cHotY vertical position of the hot spot
* @param cWidth width in pixels of the cursor
* @param cHeight height in pixels of the cursor
* @param pPixels pixel data, @see VMMDevReqMousePointer for the format
* @param cbLength size in bytes of the pixel data
*/
RTDECL(bool) VBoxHGSMIUpdatePointerShape(PHGSMIGUESTCOMMANDCONTEXT pCtx,
uint32_t fFlags,
uint32_t cHotX,
uint32_t cHotY,
uint32_t cWidth,
uint32_t cHeight,
uint8_t *pPixels,
uint32_t cbLength)
{
VBVAMOUSEPOINTERSHAPE *p;
uint32_t cbData = 0;
int rc = VINF_SUCCESS;
if (fFlags & VBOX_MOUSE_POINTER_SHAPE)
{
/* Size of the pointer data: sizeof (AND mask) + sizeof (XOR_MASK) */
cbData = ((((cWidth + 7) / 8) * cHeight + 3) & ~3)
+ cWidth * 4 * cHeight;
/* If shape is supplied, then always create the pointer visible.
* See comments in 'vboxUpdatePointerShape'
*/
fFlags |= VBOX_MOUSE_POINTER_VISIBLE;
}
LogFlowFunc(("cbData %d, %dx%d\n", cbData, cWidth, cHeight));
if (cbData > cbLength)
{
LogFunc(("calculated pointer data size is too big (%d bytes, limit %d)\n",
cbData, cbLength));
return false;
}
/* Allocate the IO buffer. */
p = (VBVAMOUSEPOINTERSHAPE *)VBoxHGSMIBufferAlloc(pCtx,
sizeof(VBVAMOUSEPOINTERSHAPE)
+ cbData,
HGSMI_CH_VBVA,
VBVA_MOUSE_POINTER_SHAPE);
if (p)
{
/* Prepare data to be sent to the host. */
/* Will be updated by the host. */
p->i32Result = VINF_SUCCESS;
/* We have our custom flags in the field */
p->fu32Flags = fFlags;
p->u32HotX = cHotX;
p->u32HotY = cHotY;
p->u32Width = cWidth;
p->u32Height = cHeight;
if (p->fu32Flags & VBOX_MOUSE_POINTER_SHAPE)
/* Copy the actual pointer data. */
memcpy (p->au8Data, pPixels, cbData);
rc = VBoxHGSMIBufferSubmit(pCtx, p);
if (RT_SUCCESS(rc))
rc = p->i32Result;
/* Free the IO buffer. */
VBoxHGSMIBufferFree(pCtx, p);
}
else
rc = VERR_NO_MEMORY;
LogFlowFunc(("rc %d\n", rc));
return RT_SUCCESS(rc);
}
/** @todo Mouse pointer position to be read from VMMDev memory, address of the memory region
* can be queried from VMMDev via an IOCTL. This VMMDev memory region will contain
* host information which is needed by the guest.
*
* Reading will not cause a switch to the host.
*
* Have to take into account:
* * synchronization: host must write to the memory only from EMT,
* large structures must be read under flag, which tells the host
* that the guest is currently reading the memory (OWNER flag?).
* * guest writes: may be allocate a page for the host info and make
* the page readonly for the guest.
* * the information should be available only for additions drivers.
* * VMMDev additions driver will inform the host which version of the info it expects,
* host must support all versions.
*
*/
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