alloc-r0drv-linux.c@ 25642

Last change on this file since 25642 was 25642, checked in by vboxsync, 15 years ago
DOXYGEN -> DOXYGEN_RUNNING.
Property svn:eol-style set to `native` Property svn:keywords set to `Id`
File size: 9.7 KB

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1	/* $Id: alloc-r0drv-linux.c 25642 2010-01-05 08:19:10Z vboxsync $ */
2	/** @file
3	* IPRT - Memory Allocation, Ring-0 Driver, Linux.
4	*/
5
6	/*
7	* Copyright (C) 2006-2007 Sun Microsystems, Inc.
8	*
9	* This file is part of VirtualBox Open Source Edition (OSE), as
10	* available from http://www.virtualbox.org. This file is free software;
11	* you can redistribute it and/or modify it under the terms of the GNU
12	* General Public License (GPL) as published by the Free Software
13	* Foundation, in version 2 as it comes in the "COPYING" file of the
14	* VirtualBox OSE distribution. VirtualBox OSE is distributed in the
15	* hope that it will be useful, but WITHOUT ANY WARRANTY of any kind.
16	*
17	* The contents of this file may alternatively be used under the terms
18	* of the Common Development and Distribution License Version 1.0
19	* (CDDL) only, as it comes in the "COPYING.CDDL" file of the
20	* VirtualBox OSE distribution, in which case the provisions of the
21	* CDDL are applicable instead of those of the GPL.
22	*
23	* You may elect to license modified versions of this file under the
24	* terms and conditions of either the GPL or the CDDL or both.
25	*
26	* Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa
27	* Clara, CA 95054 USA or visit http://www.sun.com if you need
28	* additional information or have any questions.
29	*/
30
31
32	/*******************************************************************************
33	* Header Files *
34	*******************************************************************************/
35	#include "the-linux-kernel.h"
36	#include "internal/iprt.h"
37
38	#include <iprt/mem.h>
39	#include <iprt/assert.h>
40	#include "r0drv/alloc-r0drv.h"
41
42	#if defined(RT_ARCH_AMD64) \|\| defined(DOXYGEN_RUNNING)
43	/**
44	* We need memory in the module range (~2GB to ~0) this can only be obtained
45	* thru APIs that are not exported (see module_alloc()).
46	*
47	* So, we'll have to create a quick and dirty heap here using BSS memory.
48	* Very annoying and it's going to restrict us!
49	*/
50	# define RTMEMALLOC_EXEC_HEAP
51	#endif
52	#ifdef RTMEMALLOC_EXEC_HEAP
53	# include <iprt/heap.h>
54	# include <iprt/spinlock.h>
55	# include <iprt/err.h>
56	#endif
57
58
59	/*******************************************************************************
60	* Global Variables *
61	*******************************************************************************/
62	#ifdef RTMEMALLOC_EXEC_HEAP
63	/** The heap. */
64	static RTHEAPSIMPLE g_HeapExec = NIL_RTHEAPSIMPLE;
65	/** Spinlock protecting the heap. */
66	static RTSPINLOCK g_HeapExecSpinlock = NIL_RTSPINLOCK;
67
68
69	/**
70	* API for cleaning up the heap spinlock on IPRT termination.
71	* This is as RTMemExecDonate specific to AMD64 Linux/GNU.
72	*/
73	void rtR0MemExecCleanup(void)
74	{
75	RTSpinlockDestroy(g_HeapExecSpinlock);
76	g_HeapExecSpinlock = NIL_RTSPINLOCK;
77	}
78
79
80	/**
81	* Donate read+write+execute memory to the exec heap.
82	*
83	* This API is specific to AMD64 and Linux/GNU. A kernel module that desires to
84	* use RTMemExecAlloc on AMD64 Linux/GNU will have to donate some statically
85	* allocated memory in the module if it wishes for GCC generated code to work.
86	* GCC can only generate modules that work in the address range ~2GB to ~0
87	* currently.
88	*
89	* The API only accept one single donation.
90	*
91	* @returns IPRT status code.
92	* @param pvMemory Pointer to the memory block.
93	* @param cb The size of the memory block.
94	*/
95	RTR0DECL(int) RTR0MemExecDonate(void *pvMemory, size_t cb)
96	{
97	int rc;
98	AssertReturn(g_HeapExec == NIL_RTHEAPSIMPLE, VERR_WRONG_ORDER);
99
100	rc = RTSpinlockCreate(&g_HeapExecSpinlock);
101	if (RT_SUCCESS(rc))
102	{
103	rc = RTHeapSimpleInit(&g_HeapExec, pvMemory, cb);
104	if (RT_FAILURE(rc))
105	rtR0MemExecCleanup();
106	}
107	return rc;
108	}
109	RT_EXPORT_SYMBOL(RTR0MemExecDonate);
110	#endif /* RTMEMALLOC_EXEC_HEAP */
111
112
113
114	/**
115	* OS specific allocation function.
116	*/
117	PRTMEMHDR rtMemAlloc(size_t cb, uint32_t fFlags)
118	{
119	/*
120	* Allocate.
121	*/
122	PRTMEMHDR pHdr;
123	if (fFlags & RTMEMHDR_FLAG_EXEC)
124	{
125	#if defined(RT_ARCH_AMD64)
126	# ifdef RTMEMALLOC_EXEC_HEAP
127	if (g_HeapExec != NIL_RTHEAPSIMPLE)
128	{
129	RTSPINLOCKTMP SpinlockTmp = RTSPINLOCKTMP_INITIALIZER;
130	RTSpinlockAcquireNoInts(g_HeapExecSpinlock, &SpinlockTmp);
131	pHdr = (PRTMEMHDR)RTHeapSimpleAlloc(g_HeapExec, cb + sizeof(*pHdr), 0);
132	RTSpinlockReleaseNoInts(g_HeapExecSpinlock, &SpinlockTmp);
133	fFlags \|= RTMEMHDR_FLAG_EXEC_HEAP;
134	}
135	else
136	pHdr = NULL;
137	# else /* !RTMEMALLOC_EXEC_HEAP */
138	pHdr = (PRTMEMHDR)__vmalloc(cb + sizeof(*pHdr), GFP_KERNEL \| __GFP_HIGHMEM, MY_PAGE_KERNEL_EXEC);
139	# endif /* !RTMEMALLOC_EXEC_HEAP */
140
141	#elif defined(PAGE_KERNEL_EXEC) && defined(CONFIG_X86_PAE)
142	pHdr = (PRTMEMHDR)__vmalloc(cb + sizeof(*pHdr), GFP_KERNEL \| __GFP_HIGHMEM, MY_PAGE_KERNEL_EXEC);
143	#else
144	pHdr = (PRTMEMHDR)vmalloc(cb + sizeof(*pHdr));
145	#endif
146	}
147	else
148	{
149	if (cb <= PAGE_SIZE)
150	{
151	fFlags \|= RTMEMHDR_FLAG_KMALLOC;
152	pHdr = kmalloc(cb + sizeof(*pHdr), GFP_KERNEL);
153	}
154	else
155	pHdr = vmalloc(cb + sizeof(*pHdr));
156	}
157
158	/*
159	* Initialize.
160	*/
161	if (pHdr)
162	{
163	pHdr->u32Magic = RTMEMHDR_MAGIC;
164	pHdr->fFlags = fFlags;
165	pHdr->cb = cb;
166	pHdr->cbReq = cb;
167	}
168	return pHdr;
169	}
170
171
172	/**
173	* OS specific free function.
174	*/
175	void rtMemFree(PRTMEMHDR pHdr)
176	{
177	pHdr->u32Magic += 1;
178	if (pHdr->fFlags & RTMEMHDR_FLAG_KMALLOC)
179	kfree(pHdr);
180	#ifdef RTMEMALLOC_EXEC_HEAP
181	else if (pHdr->fFlags & RTMEMHDR_FLAG_EXEC_HEAP)
182	{
183	RTSPINLOCKTMP SpinlockTmp = RTSPINLOCKTMP_INITIALIZER;
184	RTSpinlockAcquireNoInts(g_HeapExecSpinlock, &SpinlockTmp);
185	RTHeapSimpleFree(g_HeapExec, pHdr);
186	RTSpinlockReleaseNoInts(g_HeapExecSpinlock, &SpinlockTmp);
187	}
188	#endif
189	else
190	vfree(pHdr);
191	}
192
193
194	/**
195	* Compute order. Some functions allocate 2^order pages.
196	*
197	* @returns order.
198	* @param cPages Number of pages.
199	*/
200	static int CalcPowerOf2Order(unsigned long cPages)
201	{
202	int iOrder;
203	unsigned long cTmp;
204
205	for (iOrder = 0, cTmp = cPages; cTmp >>= 1; ++iOrder)
206	;
207	if (cPages & ~(1 << iOrder))
208	++iOrder;
209
210	return iOrder;
211	}
212
213
214	/**
215	* Allocates physical contiguous memory (below 4GB).
216	* The allocation is page aligned and the content is undefined.
217	*
218	* @returns Pointer to the memory block. This is page aligned.
219	* @param pPhys Where to store the physical address.
220	* @param cb The allocation size in bytes. This is always
221	* rounded up to PAGE_SIZE.
222	*/
223	RTR0DECL(void *) RTMemContAlloc(PRTCCPHYS pPhys, size_t cb)
224	{
225	int cOrder;
226	unsigned cPages;
227	struct page *paPages;
228
229	/*
230	* validate input.
231	*/
232	Assert(VALID_PTR(pPhys));
233	Assert(cb > 0);
234
235	/*
236	* Allocate page pointer array.
237	*/
238	cb = RT_ALIGN_Z(cb, PAGE_SIZE);
239	cPages = cb >> PAGE_SHIFT;
240	cOrder = CalcPowerOf2Order(cPages);
241	#if (defined(RT_ARCH_AMD64) \|\| defined(CONFIG_X86_PAE)) && defined(GFP_DMA32)
242	/* ZONE_DMA32: 0-4GB */
243	paPages = alloc_pages(GFP_DMA32, cOrder);
244	if (!paPages)
245	#endif
246	#ifdef RT_ARCH_AMD64
247	/* ZONE_DMA; 0-16MB */
248	paPages = alloc_pages(GFP_DMA, cOrder);
249	#else
250	/* ZONE_NORMAL: 0-896MB */
251	paPages = alloc_pages(GFP_USER, cOrder);
252	#endif
253	if (paPages)
254	{
255	/*
256	* Reserve the pages and mark them executable.
257	*/
258	unsigned iPage;
259	for (iPage = 0; iPage < cPages; iPage++)
260	{
261	Assert(!PageHighMem(&paPages[iPage]));
262	if (iPage + 1 < cPages)
263	{
264	AssertMsg( (uintptr_t)phys_to_virt(page_to_phys(&paPages[iPage])) + PAGE_SIZE
265	== (uintptr_t)phys_to_virt(page_to_phys(&paPages[iPage + 1]))
266	&& page_to_phys(&paPages[iPage]) + PAGE_SIZE
267	== page_to_phys(&paPages[iPage + 1]),
268	("iPage=%i cPages=%u [0]=%#llx,%p [1]=%#llx,%p\n", iPage, cPages,
269	(long long)page_to_phys(&paPages[iPage]), phys_to_virt(page_to_phys(&paPages[iPage])),
270	(long long)page_to_phys(&paPages[iPage + 1]), phys_to_virt(page_to_phys(&paPages[iPage + 1])) ));
271	}
272
273	SetPageReserved(&paPages[iPage]);
274	#if LINUX_VERSION_CODE > KERNEL_VERSION(2, 4, 20) /** @todo find the exact kernel where change_page_attr was introduced. */
275	MY_SET_PAGES_EXEC(&paPages[iPage], 1);
276	#endif
277	}
278	*pPhys = page_to_phys(paPages);
279	return phys_to_virt(page_to_phys(paPages));
280	}
281
282	return NULL;
283	}
284	RT_EXPORT_SYMBOL(RTMemContAlloc);
285
286
287	/**
288	* Frees memory allocated ysing RTMemContAlloc().
289	*
290	* @param pv Pointer to return from RTMemContAlloc().
291	* @param cb The cb parameter passed to RTMemContAlloc().
292	*/
293	RTR0DECL(void) RTMemContFree(void *pv, size_t cb)
294	{
295	if (pv)
296	{
297	int cOrder;
298	unsigned cPages;
299	unsigned iPage;
300	struct page *paPages;
301
302	/* validate */
303	AssertMsg(!((uintptr_t)pv & PAGE_OFFSET_MASK), ("pv=%p\n", pv));
304	Assert(cb > 0);
305
306	/* calc order and get pages */
307	cb = RT_ALIGN_Z(cb, PAGE_SIZE);
308	cPages = cb >> PAGE_SHIFT;
309	cOrder = CalcPowerOf2Order(cPages);
310	paPages = virt_to_page(pv);
311
312	/*
313	* Restore page attributes freeing the pages.
314	*/
315	for (iPage = 0; iPage < cPages; iPage++)
316	{
317	ClearPageReserved(&paPages[iPage]);
318	#if LINUX_VERSION_CODE > KERNEL_VERSION(2, 4, 20) /** @todo find the exact kernel where change_page_attr was introduced. */
319	MY_SET_PAGES_NOEXEC(&paPages[iPage], 1);
320	#endif
321	}
322	__free_pages(paPages, cOrder);
323	}
324	}
325	RT_EXPORT_SYMBOL(RTMemContFree);
326

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source: vbox/trunk/src/VBox/Runtime/r0drv/linux/alloc-r0drv-linux.c@ 25642

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