| 1 | /* $Id: alloc-r0drv-linux.c 4071 2007-08-07 17:07:59Z vboxsync $ */
|
|---|
| 2 | /** @file
|
|---|
| 3 | * innotek Portable Runtime - Memory Allocation, Ring-0 Driver, Linux.
|
|---|
| 4 | */
|
|---|
| 5 |
|
|---|
| 6 | /*
|
|---|
| 7 | * Copyright (C) 2006-2007 innotek GmbH
|
|---|
| 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 as published by the Free Software Foundation,
|
|---|
| 13 | * in version 2 as it comes in the "COPYING" file of the VirtualBox OSE
|
|---|
| 14 | * distribution. VirtualBox OSE is distributed in the hope that it will
|
|---|
| 15 | * be useful, but WITHOUT ANY WARRANTY of any kind.
|
|---|
| 16 | */
|
|---|
| 17 |
|
|---|
| 18 |
|
|---|
| 19 | /*******************************************************************************
|
|---|
| 20 | * Header Files *
|
|---|
| 21 | *******************************************************************************/
|
|---|
| 22 | #include "the-linux-kernel.h"
|
|---|
| 23 | #include <iprt/mem.h>
|
|---|
| 24 | #include <iprt/assert.h>
|
|---|
| 25 | #include "r0drv/alloc-r0drv.h"
|
|---|
| 26 |
|
|---|
| 27 | #if defined(RT_ARCH_AMD64) || defined(__DOXYGEN__)
|
|---|
| 28 | /**
|
|---|
| 29 | * We need memory in the module range (~2GB to ~0) this can only be obtained
|
|---|
| 30 | * thru APIs that are not exported (see module_alloc()).
|
|---|
| 31 | *
|
|---|
| 32 | * So, we'll have to create a quick and dirty heap here using BSS memory.
|
|---|
| 33 | * Very annoying and it's going to restrict us!
|
|---|
| 34 | */
|
|---|
| 35 | # define RTMEMALLOC_EXEC_HEAP
|
|---|
| 36 | #endif
|
|---|
| 37 | #ifdef RTMEMALLOC_EXEC_HEAP
|
|---|
| 38 | # include <iprt/heap.h>
|
|---|
| 39 | # include <iprt/spinlock.h>
|
|---|
| 40 | # include <iprt/err.h>
|
|---|
| 41 | #endif
|
|---|
| 42 |
|
|---|
| 43 |
|
|---|
| 44 | /*******************************************************************************
|
|---|
| 45 | * Global Variables *
|
|---|
| 46 | *******************************************************************************/
|
|---|
| 47 | #ifdef RTMEMALLOC_EXEC_HEAP
|
|---|
| 48 | /** The heap. */
|
|---|
| 49 | static RTHEAPSIMPLE g_HeapExec = NIL_RTHEAPSIMPLE;
|
|---|
| 50 | /** Spinlock protecting the heap. */
|
|---|
| 51 | static RTSPINLOCK g_HeapExecSpinlock = NIL_RTSPINLOCK;
|
|---|
| 52 |
|
|---|
| 53 |
|
|---|
| 54 | /**
|
|---|
| 55 | * API for cleaning up the heap spinlock on IPRT termination.
|
|---|
| 56 | * This is as RTMemExecDonate specific to AMD64 Linux/GNU.
|
|---|
| 57 | */
|
|---|
| 58 | void rtR0MemExecCleanup(void)
|
|---|
| 59 | {
|
|---|
| 60 | RTSpinlockDestroy(g_HeapExecSpinlock);
|
|---|
| 61 | g_HeapExecSpinlock = NIL_RTSPINLOCK;
|
|---|
| 62 | }
|
|---|
| 63 |
|
|---|
| 64 |
|
|---|
| 65 | /**
|
|---|
| 66 | * Donate read+write+execute memory to the exec heap.
|
|---|
| 67 | *
|
|---|
| 68 | * This API is specific to AMD64 and Linux/GNU. A kernel module that desires to
|
|---|
| 69 | * use RTMemExecAlloc on AMD64 Linux/GNU will have to donate some statically
|
|---|
| 70 | * allocated memory in the module if it wishes for GCC generated code to work.
|
|---|
| 71 | * GCC can only generate modules that work in the address range ~2GB to ~0
|
|---|
| 72 | * currently.
|
|---|
| 73 | *
|
|---|
| 74 | * The API only accept one single donation.
|
|---|
| 75 | *
|
|---|
| 76 | * @returns IPRT status code.
|
|---|
| 77 | * @param pvMemory Pointer to the memory block.
|
|---|
| 78 | * @param cb The size of the memory block.
|
|---|
| 79 | */
|
|---|
| 80 | RTR0DECL(int) RTR0MemExecDonate(void *pvMemory, size_t cb)
|
|---|
| 81 | {
|
|---|
| 82 | int rc;
|
|---|
| 83 | AssertReturn(g_HeapExec == NIL_RTHEAPSIMPLE, VERR_WRONG_ORDER);
|
|---|
| 84 |
|
|---|
| 85 | rc = RTSpinlockCreate(&g_HeapExecSpinlock);
|
|---|
| 86 | if (RT_SUCCESS(rc))
|
|---|
| 87 | {
|
|---|
| 88 | rc = RTHeapSimpleInit(&g_HeapExec, pvMemory, cb);
|
|---|
| 89 | if (RT_FAILURE(rc))
|
|---|
| 90 | rtR0MemExecCleanup();
|
|---|
| 91 | }
|
|---|
| 92 | return rc;
|
|---|
| 93 | }
|
|---|
| 94 | #endif /* RTMEMALLOC_EXEC_HEAP */
|
|---|
| 95 |
|
|---|
| 96 |
|
|---|
| 97 |
|
|---|
| 98 | /**
|
|---|
| 99 | * OS specific allocation function.
|
|---|
| 100 | */
|
|---|
| 101 | PRTMEMHDR rtMemAlloc(size_t cb, uint32_t fFlags)
|
|---|
| 102 | {
|
|---|
| 103 | /*
|
|---|
| 104 | * Allocate.
|
|---|
| 105 | */
|
|---|
| 106 | PRTMEMHDR pHdr;
|
|---|
| 107 | Assert(cb != sizeof(void *)); /* 99% of pointer sized allocations are wrong. */
|
|---|
| 108 | if (fFlags & RTMEMHDR_FLAG_EXEC)
|
|---|
| 109 | {
|
|---|
| 110 | #if defined(RT_ARCH_AMD64)
|
|---|
| 111 | # ifdef RTMEMALLOC_EXEC_HEAP
|
|---|
| 112 | if (g_HeapExec != NIL_RTHEAPSIMPLE)
|
|---|
| 113 | {
|
|---|
| 114 | RTSPINLOCKTMP SpinlockTmp = RTSPINLOCKTMP_INITIALIZER;
|
|---|
| 115 | RTSpinlockAcquireNoInts(g_HeapExecSpinlock, &SpinlockTmp);
|
|---|
| 116 | pHdr = (PRTMEMHDR)RTHeapSimpleAlloc(g_HeapExec, cb + sizeof(*pHdr), 0);
|
|---|
| 117 | RTSpinlockReleaseNoInts(g_HeapExecSpinlock, &SpinlockTmp);
|
|---|
| 118 | fFlags |= RTMEMHDR_FLAG_EXEC_HEAP;
|
|---|
| 119 | }
|
|---|
| 120 | else
|
|---|
| 121 | # endif
|
|---|
| 122 | pHdr = (PRTMEMHDR)__vmalloc(cb + sizeof(*pHdr), GFP_KERNEL | __GFP_HIGHMEM, PAGE_KERNEL_EXEC);
|
|---|
| 123 |
|
|---|
| 124 | #elif defined(PAGE_KERNEL_EXEC) && defined(CONFIG_X86_PAE)
|
|---|
| 125 | pHdr = (PRTMEMHDR)__vmalloc(cb + sizeof(*pHdr), GFP_KERNEL | __GFP_HIGHMEM,
|
|---|
| 126 | __pgprot(cpu_has_pge ? _PAGE_KERNEL_EXEC | _PAGE_GLOBAL : _PAGE_KERNEL_EXEC));
|
|---|
| 127 | #else
|
|---|
| 128 | pHdr = (PRTMEMHDR)vmalloc(cb + sizeof(*pHdr));
|
|---|
| 129 | #endif
|
|---|
| 130 | }
|
|---|
| 131 | else
|
|---|
| 132 | {
|
|---|
| 133 | if (cb <= PAGE_SIZE)
|
|---|
| 134 | {
|
|---|
| 135 | fFlags |= RTMEMHDR_FLAG_KMALLOC;
|
|---|
| 136 | pHdr = kmalloc(cb + sizeof(*pHdr), GFP_KERNEL);
|
|---|
| 137 | }
|
|---|
| 138 | else
|
|---|
| 139 | pHdr = vmalloc(cb + sizeof(*pHdr));
|
|---|
| 140 | }
|
|---|
| 141 |
|
|---|
| 142 | /*
|
|---|
| 143 | * Initialize.
|
|---|
| 144 | */
|
|---|
| 145 | if (pHdr)
|
|---|
| 146 | {
|
|---|
| 147 | pHdr->u32Magic = RTMEMHDR_MAGIC;
|
|---|
| 148 | pHdr->fFlags = fFlags;
|
|---|
| 149 | pHdr->cb = cb;
|
|---|
| 150 | pHdr->u32Padding= 0;
|
|---|
| 151 | }
|
|---|
| 152 | return pHdr;
|
|---|
| 153 | }
|
|---|
| 154 |
|
|---|
| 155 |
|
|---|
| 156 | /**
|
|---|
| 157 | * OS specific free function.
|
|---|
| 158 | */
|
|---|
| 159 | void rtMemFree(PRTMEMHDR pHdr)
|
|---|
| 160 | {
|
|---|
| 161 | pHdr->u32Magic += 1;
|
|---|
| 162 | if (pHdr->fFlags & RTMEMHDR_FLAG_KMALLOC)
|
|---|
| 163 | kfree(pHdr);
|
|---|
| 164 | #ifdef RTMEMALLOC_EXEC_HEAP
|
|---|
| 165 | else if (pHdr->fFlags & RTMEMHDR_FLAG_EXEC_HEAP)
|
|---|
| 166 | {
|
|---|
| 167 | RTSPINLOCKTMP SpinlockTmp = RTSPINLOCKTMP_INITIALIZER;
|
|---|
| 168 | RTSpinlockAcquireNoInts(g_HeapExecSpinlock, &SpinlockTmp);
|
|---|
| 169 | RTHeapSimpleFree(g_HeapExec, pHdr);
|
|---|
| 170 | RTSpinlockReleaseNoInts(g_HeapExecSpinlock, &SpinlockTmp);
|
|---|
| 171 | }
|
|---|
| 172 | #endif
|
|---|
| 173 | else
|
|---|
| 174 | vfree(pHdr);
|
|---|
| 175 | }
|
|---|
| 176 |
|
|---|
| 177 |
|
|---|
| 178 | /**
|
|---|
| 179 | * Compute order. Some functions allocate 2^order pages.
|
|---|
| 180 | *
|
|---|
| 181 | * @returns order.
|
|---|
| 182 | * @param cPages Number of pages.
|
|---|
| 183 | */
|
|---|
| 184 | static int CalcPowerOf2Order(unsigned long cPages)
|
|---|
| 185 | {
|
|---|
| 186 | int iOrder;
|
|---|
| 187 | unsigned long cTmp;
|
|---|
| 188 |
|
|---|
| 189 | for (iOrder = 0, cTmp = cPages; cTmp >>= 1; ++iOrder)
|
|---|
| 190 | ;
|
|---|
| 191 | if (cPages & ~(1 << iOrder))
|
|---|
| 192 | ++iOrder;
|
|---|
| 193 |
|
|---|
| 194 | return iOrder;
|
|---|
| 195 | }
|
|---|
| 196 |
|
|---|
| 197 |
|
|---|
| 198 | /**
|
|---|
| 199 | * Allocates physical contiguous memory (below 4GB).
|
|---|
| 200 | * The allocation is page aligned and the content is undefined.
|
|---|
| 201 | *
|
|---|
| 202 | * @returns Pointer to the memory block. This is page aligned.
|
|---|
| 203 | * @param pPhys Where to store the physical address.
|
|---|
| 204 | * @param cb The allocation size in bytes. This is always
|
|---|
| 205 | * rounded up to PAGE_SIZE.
|
|---|
| 206 | */
|
|---|
| 207 | RTR0DECL(void *) RTMemContAlloc(PRTCCPHYS pPhys, size_t cb)
|
|---|
| 208 | {
|
|---|
| 209 | int cOrder;
|
|---|
| 210 | unsigned cPages;
|
|---|
| 211 | struct page *paPages;
|
|---|
| 212 |
|
|---|
| 213 | /*
|
|---|
| 214 | * validate input.
|
|---|
| 215 | */
|
|---|
| 216 | Assert(VALID_PTR(pPhys));
|
|---|
| 217 | Assert(cb > 0);
|
|---|
| 218 |
|
|---|
| 219 | /*
|
|---|
| 220 | * Allocate page pointer array.
|
|---|
| 221 | */
|
|---|
| 222 | cb = RT_ALIGN_Z(cb, PAGE_SIZE);
|
|---|
| 223 | cPages = cb >> PAGE_SHIFT;
|
|---|
| 224 | cOrder = CalcPowerOf2Order(cPages);
|
|---|
| 225 | #ifdef RT_ARCH_AMD64 /** @todo check out if there is a correct way of getting memory below 4GB (physically). */
|
|---|
| 226 | paPages = alloc_pages(GFP_DMA, cOrder);
|
|---|
| 227 | #else
|
|---|
| 228 | paPages = alloc_pages(GFP_USER, cOrder);
|
|---|
| 229 | #endif
|
|---|
| 230 | if (paPages)
|
|---|
| 231 | {
|
|---|
| 232 | /*
|
|---|
| 233 | * Reserve the pages and mark them executable.
|
|---|
| 234 | */
|
|---|
| 235 | unsigned iPage;
|
|---|
| 236 | for (iPage = 0; iPage < cPages; iPage++)
|
|---|
| 237 | {
|
|---|
| 238 | Assert(!PageHighMem(&paPages[iPage]));
|
|---|
| 239 | if (iPage + 1 < cPages)
|
|---|
| 240 | {
|
|---|
| 241 | AssertMsg( (uintptr_t)phys_to_virt(page_to_phys(&paPages[iPage])) + PAGE_SIZE
|
|---|
| 242 | == (uintptr_t)phys_to_virt(page_to_phys(&paPages[iPage + 1]))
|
|---|
| 243 | && page_to_phys(&paPages[iPage]) + PAGE_SIZE
|
|---|
| 244 | == page_to_phys(&paPages[iPage + 1]),
|
|---|
| 245 | ("iPage=%i cPages=%u [0]=%#llx,%p [1]=%#llx,%p\n", iPage, cPages,
|
|---|
| 246 | (long long)page_to_phys(&paPages[iPage]), phys_to_virt(page_to_phys(&paPages[iPage])),
|
|---|
| 247 | (long long)page_to_phys(&paPages[iPage + 1]), phys_to_virt(page_to_phys(&paPages[iPage + 1])) ));
|
|---|
| 248 | }
|
|---|
| 249 |
|
|---|
| 250 | SetPageReserved(&paPages[iPage]);
|
|---|
| 251 | #if LINUX_VERSION_CODE > KERNEL_VERSION(2, 4, 20) /** @todo find the exact kernel where change_page_attr was introduced. */
|
|---|
| 252 | if (pgprot_val(MY_PAGE_KERNEL_EXEC) != pgprot_val(PAGE_KERNEL))
|
|---|
| 253 | MY_CHANGE_PAGE_ATTR(&paPages[iPage], 1, MY_PAGE_KERNEL_EXEC);
|
|---|
| 254 | #endif
|
|---|
| 255 | }
|
|---|
| 256 | *pPhys = page_to_phys(paPages);
|
|---|
| 257 | return phys_to_virt(page_to_phys(paPages));
|
|---|
| 258 | }
|
|---|
| 259 |
|
|---|
| 260 | return NULL;
|
|---|
| 261 | }
|
|---|
| 262 |
|
|---|
| 263 |
|
|---|
| 264 | /**
|
|---|
| 265 | * Frees memory allocated ysing RTMemContAlloc().
|
|---|
| 266 | *
|
|---|
| 267 | * @param pv Pointer to return from RTMemContAlloc().
|
|---|
| 268 | * @param cb The cb parameter passed to RTMemContAlloc().
|
|---|
| 269 | */
|
|---|
| 270 | RTR0DECL(void) RTMemContFree(void *pv, size_t cb)
|
|---|
| 271 | {
|
|---|
| 272 | if (pv)
|
|---|
| 273 | {
|
|---|
| 274 | int cOrder;
|
|---|
| 275 | unsigned cPages;
|
|---|
| 276 | unsigned iPage;
|
|---|
| 277 | struct page *paPages;
|
|---|
| 278 |
|
|---|
| 279 | /* validate */
|
|---|
| 280 | AssertMsg(!((uintptr_t)pv & PAGE_OFFSET_MASK), ("pv=%p\n", pv));
|
|---|
| 281 | Assert(cb > 0);
|
|---|
| 282 |
|
|---|
| 283 | /* calc order and get pages */
|
|---|
| 284 | cb = RT_ALIGN_Z(cb, PAGE_SIZE);
|
|---|
| 285 | cPages = cb >> PAGE_SHIFT;
|
|---|
| 286 | cOrder = CalcPowerOf2Order(cPages);
|
|---|
| 287 | paPages = virt_to_page(pv);
|
|---|
| 288 |
|
|---|
| 289 | /*
|
|---|
| 290 | * Restore page attributes freeing the pages.
|
|---|
| 291 | */
|
|---|
| 292 | for (iPage = 0; iPage < cPages; iPage++)
|
|---|
| 293 | {
|
|---|
| 294 | ClearPageReserved(&paPages[iPage]);
|
|---|
| 295 | #if LINUX_VERSION_CODE > KERNEL_VERSION(2, 4, 20) /** @todo find the exact kernel where change_page_attr was introduced. */
|
|---|
| 296 | if (pgprot_val(MY_PAGE_KERNEL_EXEC) != pgprot_val(PAGE_KERNEL))
|
|---|
| 297 | MY_CHANGE_PAGE_ATTR(&paPages[iPage], 1, PAGE_KERNEL);
|
|---|
| 298 | #endif
|
|---|
| 299 | }
|
|---|
| 300 | __free_pages(paPages, cOrder);
|
|---|
| 301 | }
|
|---|
| 302 | }
|
|---|
| 303 |
|
|---|
