Current File : //usr/share/virtualbox/src/vboxhost/vboxdrv/r0drv/linux/alloc-r0drv-linux.c
/* $Id: alloc-r0drv-linux.c 155244 2023-01-17 14:15:46Z bird $ */
/** @file
* IPRT - Memory Allocation, Ring-0 Driver, Linux.
*/
/*
* Copyright (C) 2006-2023 Oracle and/or its affiliates.
*
* This file is part of VirtualBox base platform packages, as
* available from https://www.virtualbox.org.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation, in version 3 of the
* License.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, see <https://www.gnu.org/licenses>.
*
* The contents of this file may alternatively be used under the terms
* of the Common Development and Distribution License Version 1.0
* (CDDL), a copy of it is provided in the "COPYING.CDDL" file included
* in the VirtualBox distribution, in which case the provisions of the
* CDDL are applicable instead of those of the GPL.
*
* You may elect to license modified versions of this file under the
* terms and conditions of either the GPL or the CDDL or both.
*
* SPDX-License-Identifier: GPL-3.0-only OR CDDL-1.0
*/
/*********************************************************************************************************************************
* Header Files *
*********************************************************************************************************************************/
#include "the-linux-kernel.h"
#include "internal/iprt.h"
#include <iprt/mem.h>
#include <iprt/assert.h>
#include <iprt/errcore.h>
#include "r0drv/alloc-r0drv.h"
#include "internal/initterm.h"
/**
* OS specific allocation function.
*/
DECLHIDDEN(int) rtR0MemAllocEx(size_t cb, uint32_t fFlags, PRTMEMHDR *ppHdr)
{
PRTMEMHDR pHdr;
IPRT_LINUX_SAVE_EFL_AC();
/*
* Allocate.
*/
if (
#if 1 /* vmalloc has serious performance issues, avoid it. */
cb <= PAGE_SIZE*16 - sizeof(*pHdr)
#else
cb <= PAGE_SIZE
#endif
|| (fFlags & RTMEMHDR_FLAG_ANY_CTX)
)
{
fFlags |= RTMEMHDR_FLAG_KMALLOC;
pHdr = kmalloc(cb + sizeof(*pHdr),
fFlags & RTMEMHDR_FLAG_ANY_CTX_ALLOC ? GFP_ATOMIC | __GFP_NOWARN : GFP_KERNEL | __GFP_NOWARN);
if (RT_UNLIKELY( !pHdr
&& cb > PAGE_SIZE
&& !(fFlags & RTMEMHDR_FLAG_ANY_CTX) ))
{
fFlags &= ~RTMEMHDR_FLAG_KMALLOC;
pHdr = vmalloc(cb + sizeof(*pHdr));
}
}
else
pHdr = vmalloc(cb + sizeof(*pHdr));
if (RT_LIKELY(pHdr))
{
/*
* Initialize.
*/
pHdr->u32Magic = RTMEMHDR_MAGIC;
pHdr->fFlags = fFlags;
pHdr->cb = cb;
pHdr->cbReq = cb;
*ppHdr = pHdr;
IPRT_LINUX_RESTORE_EFL_AC();
return VINF_SUCCESS;
}
IPRT_LINUX_RESTORE_EFL_AC();
return VERR_NO_MEMORY;
}
/**
* OS specific free function.
*/
DECLHIDDEN(void) rtR0MemFree(PRTMEMHDR pHdr)
{
IPRT_LINUX_SAVE_EFL_AC();
pHdr->u32Magic += 1;
if (pHdr->fFlags & RTMEMHDR_FLAG_KMALLOC)
kfree(pHdr);
else
vfree(pHdr);
IPRT_LINUX_RESTORE_EFL_AC();
}
/**
* Compute order. Some functions allocate 2^order pages.
*
* @returns order.
* @param cPages Number of pages.
*/
static int CalcPowerOf2Order(unsigned long cPages)
{
int iOrder;
unsigned long cTmp;
for (iOrder = 0, cTmp = cPages; cTmp >>= 1; ++iOrder)
;
if (cPages & ~(1 << iOrder))
++iOrder;
return iOrder;
}
/**
* Allocates physical contiguous memory (below 4GB).
* The allocation is page aligned and the content is undefined.
*
* @returns Pointer to the memory block. This is page aligned.
* @param pPhys Where to store the physical address.
* @param cb The allocation size in bytes. This is always
* rounded up to PAGE_SIZE.
*/
RTR0DECL(void *) RTMemContAlloc(PRTCCPHYS pPhys, size_t cb)
{
int cOrder;
unsigned cPages;
struct page *paPages;
void *pvRet;
IPRT_LINUX_SAVE_EFL_AC();
/*
* validate input.
*/
AssertPtr(pPhys);
Assert(cb > 0);
/*
* Allocate page pointer array.
*/
cb = RT_ALIGN_Z(cb, PAGE_SIZE);
cPages = cb >> PAGE_SHIFT;
cOrder = CalcPowerOf2Order(cPages);
#if (defined(RT_ARCH_AMD64) || defined(CONFIG_X86_PAE)) && defined(GFP_DMA32)
/* ZONE_DMA32: 0-4GB */
paPages = alloc_pages(GFP_DMA32 | __GFP_NOWARN, cOrder);
if (!paPages)
#endif
#ifdef RT_ARCH_AMD64
/* ZONE_DMA; 0-16MB */
paPages = alloc_pages(GFP_DMA | __GFP_NOWARN, cOrder);
#else
/* ZONE_NORMAL: 0-896MB */
paPages = alloc_pages(GFP_USER | __GFP_NOWARN, cOrder);
#endif
if (paPages)
{
/*
* Reserve the pages and mark them executable.
*/
unsigned iPage;
for (iPage = 0; iPage < cPages; iPage++)
{
Assert(!PageHighMem(&paPages[iPage]));
if (iPage + 1 < cPages)
{
AssertMsg( (uintptr_t)phys_to_virt(page_to_phys(&paPages[iPage])) + PAGE_SIZE
== (uintptr_t)phys_to_virt(page_to_phys(&paPages[iPage + 1]))
&& page_to_phys(&paPages[iPage]) + PAGE_SIZE
== page_to_phys(&paPages[iPage + 1]),
("iPage=%i cPages=%u [0]=%#llx,%p [1]=%#llx,%p\n", iPage, cPages,
(long long)page_to_phys(&paPages[iPage]), phys_to_virt(page_to_phys(&paPages[iPage])),
(long long)page_to_phys(&paPages[iPage + 1]), phys_to_virt(page_to_phys(&paPages[iPage + 1])) ));
}
SetPageReserved(&paPages[iPage]);
}
*pPhys = page_to_phys(paPages);
pvRet = phys_to_virt(page_to_phys(paPages));
}
else
pvRet = NULL;
IPRT_LINUX_RESTORE_EFL_AC();
return pvRet;
}
RT_EXPORT_SYMBOL(RTMemContAlloc);
/**
* Frees memory allocated using RTMemContAlloc().
*
* @param pv Pointer to return from RTMemContAlloc().
* @param cb The cb parameter passed to RTMemContAlloc().
*/
RTR0DECL(void) RTMemContFree(void *pv, size_t cb)
{
if (pv)
{
int cOrder;
unsigned cPages;
unsigned iPage;
struct page *paPages;
IPRT_LINUX_SAVE_EFL_AC();
/* validate */
AssertMsg(!((uintptr_t)pv & PAGE_OFFSET_MASK), ("pv=%p\n", pv));
Assert(cb > 0);
/* calc order and get pages */
cb = RT_ALIGN_Z(cb, PAGE_SIZE);
cPages = cb >> PAGE_SHIFT;
cOrder = CalcPowerOf2Order(cPages);
paPages = virt_to_page(pv);
/*
* Restore page attributes freeing the pages.
*/
for (iPage = 0; iPage < cPages; iPage++)
{
ClearPageReserved(&paPages[iPage]);
}
__free_pages(paPages, cOrder);
IPRT_LINUX_RESTORE_EFL_AC();
}
}
RT_EXPORT_SYMBOL(RTMemContFree);
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