1 2 /*--------------------------------------------------------------------*/ 3 /*--- The address space manager. pub_core_aspacemgr.h ---*/ 4 /*--------------------------------------------------------------------*/ 5 6 /* 7 This file is part of Valgrind, a dynamic binary instrumentation 8 framework. 9 10 Copyright (C) 2000-2011 Julian Seward 11 jseward@acm.org 12 13 This program is free software; you can redistribute it and/or 14 modify it under the terms of the GNU General Public License as 15 published by the Free Software Foundation; either version 2 of the 16 License, or (at your option) any later version. 17 18 This program is distributed in the hope that it will be useful, but 19 WITHOUT ANY WARRANTY; without even the implied warranty of 20 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 21 General Public License for more details. 22 23 You should have received a copy of the GNU General Public License 24 along with this program; if not, write to the Free Software 25 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 26 02111-1307, USA. 27 28 The GNU General Public License is contained in the file COPYING. 29 */ 30 31 #ifndef __PUB_CORE_ASPACEMGR_H 32 #define __PUB_CORE_ASPACEMGR_H 33 34 //-------------------------------------------------------------------- 35 // PURPOSE: This module deals with management of the entire process 36 // address space. Almost everything depends upon it, including dynamic 37 // memory management. Hence this module is almost completely 38 // standalone; the only module it uses is m_debuglog. DO NOT CHANGE 39 // THIS. 40 //-------------------------------------------------------------------- 41 42 #include "pub_tool_aspacemgr.h" 43 44 //-------------------------------------------------------------- 45 // Definition of address-space segments 46 47 /* types SegKind, ShrinkMode and NSegment are described in 48 the tool-visible header file, not here. */ 49 50 51 //-------------------------------------------------------------- 52 // Initialisation 53 54 /* Initialise the address space manager, setting up the initial 55 segment list, and reading /proc/self/maps into it. This must 56 be called before any other function. 57 58 Takes a pointer to the SP at the time V gained control. This is 59 taken to be the highest usable address (more or less). Based on 60 that (and general consultation of tea leaves, etc) return a 61 suggested end address for the client's stack. */ 62 extern Addr VG_(am_startup) ( Addr sp_at_startup ); 63 64 65 //-------------------------------------------------------------- 66 // Querying current status 67 68 /* Finds the segment containing 'a'. Only returns file/anon/resvn 69 segments. This returns a 'NSegment const *' - a pointer to 70 readonly data. */ 71 // Is in tool-visible header file. 72 // extern NSegment const * VG_(am_find_nsegment) ( Addr a ); 73 74 /* Find the next segment along from 'here', if it is a file/anon/resvn 75 segment. */ 76 extern NSegment const* VG_(am_next_nsegment) ( NSegment* here, Bool fwds ); 77 78 /* Is the area [start .. start+len-1] validly accessible by the 79 client with at least the permissions 'prot' ? To find out 80 simply if said area merely belongs to the client, pass 81 VKI_PROT_NONE as 'prot'. Will return False if any part of the 82 area does not belong to the client or does not have at least 83 the stated permissions. */ 84 // Is in tool-visible header file. 85 // extern Bool VG_(am_is_valid_for_client) 86 // ( Addr start, SizeT len, UInt prot ); 87 88 /* Variant of VG_(am_is_valid_for_client) which allows free areas to 89 be consider part of the client's addressable space. It also 90 considers reservations to be allowable, since from the client's 91 point of view they don't exist. */ 92 extern Bool VG_(am_is_valid_for_client_or_free_or_resvn) 93 ( Addr start, SizeT len, UInt prot ); 94 95 /* Trivial fn: return the total amount of space in anonymous mappings, 96 both for V and the client. Is used for printing stats in 97 out-of-memory messages. */ 98 extern ULong VG_(am_get_anonsize_total)( void ); 99 100 /* Show the segment array on the debug log, at given loglevel. */ 101 extern void VG_(am_show_nsegments) ( Int logLevel, HChar* who ); 102 103 /* Get the filename corresponding to this segment, if known and if it 104 has one. The returned name's storage cannot be assumed to be 105 persistent, so the caller should immediately copy the name 106 elsewhere. This may return NULL if the file name is not known or 107 for arbitrary other implementation-dependent reasons, so callers 108 need to be able to handle a NULL return value. */ 109 // Is in tool-visible header file. 110 // extern HChar* VG_(am_get_filename)( NSegment* ); 111 112 /* VG_(am_get_segment_starts) is also part of this section, but its 113 prototype is tool-visible, hence not in this header file. */ 114 115 /* Sanity check: check that Valgrind and the kernel agree on the 116 address space layout. Prints offending segments and call point if 117 a discrepancy is detected, but does not abort the system. Returned 118 Bool is False if a discrepancy was found. */ 119 120 extern Bool VG_(am_do_sync_check) ( const HChar* fn, 121 const HChar* file, Int line ); 122 123 //-------------------------------------------------------------- 124 // Functions pertaining to the central query-notify mechanism 125 // used to handle mmap/munmap/mprotect resulting from client 126 // syscalls. 127 128 /* Describes a request for VG_(am_get_advisory). */ 129 typedef 130 struct { 131 enum { MFixed, MHint, MAny } rkind; 132 Addr start; 133 Addr len; 134 } 135 MapRequest; 136 137 /* Query aspacem to ask where a mapping should go. On success, the 138 advised placement is returned, and *ok is set to True. On failure, 139 zero is returned and *ok is set to False. Note that *ok must be 140 consulted by the caller to establish success or failure; that 141 cannot be established reliably from the returned value. If *ok is 142 set to False, it means aspacem has vetoed the mapping, and so the 143 caller should not proceed with it. */ 144 extern Addr VG_(am_get_advisory) 145 ( MapRequest* req, Bool forClient, /*OUT*/Bool* ok ); 146 147 /* Convenience wrapper for VG_(am_get_advisory) for client floating or 148 fixed requests. If start is zero, a floating request is issued; if 149 nonzero, a fixed request at that address is issued. Same comments 150 about return values apply. */ 151 extern Addr VG_(am_get_advisory_client_simple) 152 ( Addr start, SizeT len, /*OUT*/Bool* ok ); 153 154 /* Notifies aspacem that the client completed an mmap successfully. 155 The segment array is updated accordingly. If the returned Bool is 156 True, the caller should immediately discard translations from the 157 specified address range. */ 158 extern Bool VG_(am_notify_client_mmap) 159 ( Addr a, SizeT len, UInt prot, UInt flags, Int fd, Off64T offset ); 160 161 extern Bool VG_(am_notify_fake_client_mmap) 162 ( Addr a, SizeT len, UInt prot, UInt flags, HChar* fileName, Off64T offset ); 163 164 /* Notifies aspacem that the client completed a shmat successfully. 165 The segment array is updated accordingly. If the returned Bool is 166 True, the caller should immediately discard translations from the 167 specified address range. */ 168 extern Bool VG_(am_notify_client_shmat)( Addr a, SizeT len, UInt prot ); 169 170 /* Notifies aspacem that an mprotect was completed successfully. The 171 segment array is updated accordingly. Note, as with 172 VG_(am_notify_munmap), it is not the job of this function to reject 173 stupid mprotects, for example the client doing mprotect of 174 non-client areas. Such requests should be intercepted earlier, by 175 the syscall wrapper for mprotect. This function merely records 176 whatever it is told. If the returned Bool is True, the caller 177 should immediately discard translations from the specified address 178 range. */ 179 extern Bool VG_(am_notify_mprotect)( Addr start, SizeT len, UInt prot ); 180 181 /* Notifies aspacem that an munmap completed successfully. The 182 segment array is updated accordingly. As with 183 VG_(am_notify_munmap), we merely record the given info, and don't 184 check it for sensibleness. If the returned Bool is True, the 185 caller should immediately discard translations from the specified 186 address range. */ 187 extern Bool VG_(am_notify_munmap)( Addr start, SizeT len ); 188 189 /* Hand a raw mmap to the kernel, without aspacem updating the segment 190 array. THIS FUNCTION IS DANGEROUS -- it will cause aspacem's view 191 of the address space to diverge from that of the kernel. DO NOT 192 USE IT UNLESS YOU UNDERSTAND the request-notify model used by 193 aspacem. In short, DO NOT USE THIS FUNCTION. */ 194 extern SysRes VG_(am_do_mmap_NO_NOTIFY) 195 ( Addr start, SizeT length, UInt prot, UInt flags, Int fd, Off64T offset); 196 197 198 //-------------------------------------------------------------- 199 // Dealing with mappings which do not arise directly from the 200 // simulation of the client. These are typically used for 201 // loading the client and building its stack/data segment, before 202 // execution begins. Also for V's own administrative use. 203 204 /* --- --- --- map, unmap, protect --- --- --- */ 205 206 /* Map a file at a fixed address for the client, and update the 207 segment array accordingly. */ 208 extern SysRes VG_(am_mmap_file_fixed_client) 209 ( Addr start, SizeT length, UInt prot, Int fd, Off64T offset ); 210 extern SysRes VG_(am_mmap_named_file_fixed_client) 211 ( Addr start, SizeT length, UInt prot, Int fd, Off64T offset, const HChar *name ); 212 213 /* Map anonymously at a fixed address for the client, and update 214 the segment array accordingly. */ 215 extern SysRes VG_(am_mmap_anon_fixed_client) 216 ( Addr start, SizeT length, UInt prot ); 217 218 219 /* Map anonymously at an unconstrained address for the client, and 220 update the segment array accordingly. */ 221 extern SysRes VG_(am_mmap_anon_float_client) ( SizeT length, Int prot ); 222 223 /* Similarly, acquire new address space for the client but with 224 considerable restrictions on what can be done with it: (1) the 225 actual protections may exceed those stated in 'prot', (2) the 226 area's protections cannot be later changed using any form of 227 mprotect, and (3) the area cannot be freed using any form of 228 munmap. On Linux this behaves the same as 229 VG_(am_mmap_anon_float_client). On AIX5 this *may* allocate memory 230 by using sbrk, so as to make use of large pages on AIX. */ 231 extern SysRes VG_(am_sbrk_anon_float_client) ( SizeT length, Int prot ); 232 233 234 /* Map anonymously at an unconstrained address for V, and update the 235 segment array accordingly. This is fundamentally how V allocates 236 itself more address space when needed. */ 237 extern SysRes VG_(am_mmap_anon_float_valgrind)( SizeT cszB ); 238 239 /* Same comments apply as per VG_(am_sbrk_anon_float_client). On 240 Linux this behaves the same as VG_(am_mmap_anon_float_valgrind). */ 241 extern SysRes VG_(am_sbrk_anon_float_valgrind)( SizeT cszB ); 242 243 244 /* Map privately a file at an unconstrained address for V, and update the 245 segment array accordingly. This is used by V for transiently 246 mapping in object files to read their debug info. */ 247 extern SysRes VG_(am_mmap_file_float_valgrind) 248 ( SizeT length, UInt prot, Int fd, Off64T offset ); 249 extern SysRes VG_(am_mmap_file_float_valgrind_flags) 250 ( SizeT length, UInt prot, UInt flags, Int fd, Off64T offset ); 251 252 /* Map shared a file at an unconstrained address for V, and update the 253 segment array accordingly. This is used by V for communicating 254 with vgdb. */ 255 extern SysRes VG_(am_shared_mmap_file_float_valgrind) 256 ( SizeT length, UInt prot, Int fd, Off64T offset ); 257 258 /* Unmap the given address range and update the segment array 259 accordingly. This fails if the range isn't valid for the client. 260 If *need_discard is True after a successful return, the caller 261 should immediately discard translations from the specified address 262 range. */ 263 extern SysRes VG_(am_munmap_client)( /*OUT*/Bool* need_discard, 264 Addr start, SizeT length ); 265 266 /* Let (start,len) denote an area within a single Valgrind-owned 267 segment (anon or file). Change the ownership of [start, start+len) 268 to the client instead. Fails if (start,len) does not denote a 269 suitable segment. */ 270 extern Bool VG_(am_change_ownership_v_to_c)( Addr start, SizeT len ); 271 272 /* 'seg' must be NULL or have been obtained from 273 VG_(am_find_nsegment), and still valid. If non-NULL, and if it 274 denotes a SkAnonC (anonymous client mapping) area, set the .isCH 275 (is-client-heap) flag for that area. Otherwise do nothing. 276 (Bizarre interface so that the same code works for both Linux and 277 AIX and does not impose inefficiencies on the Linux version.) */ 278 extern void VG_(am_set_segment_isCH_if_SkAnonC)( NSegment* seg ); 279 280 /* Same idea as VG_(am_set_segment_isCH_if_SkAnonC), except set the 281 segment's hasT bit (has-cached-code) if this is SkFileC or SkAnonC 282 segment. */ 283 extern void VG_(am_set_segment_hasT_if_SkFileC_or_SkAnonC)( NSegment* ); 284 285 /* --- --- --- reservations --- --- --- */ 286 287 /* Create a reservation from START .. START+LENGTH-1, with the given 288 ShrinkMode. When checking whether the reservation can be created, 289 also ensure that at least abs(EXTRA) extra free bytes will remain 290 above (> 0) or below (< 0) the reservation. 291 292 The reservation will only be created if it, plus the extra-zone, 293 falls entirely within a single free segment. The returned Bool 294 indicates whether the creation succeeded. */ 295 extern Bool VG_(am_create_reservation) 296 ( Addr start, SizeT length, ShrinkMode smode, SSizeT extra ); 297 298 /* Let SEG be an anonymous client mapping. This fn extends the 299 mapping by DELTA bytes, taking the space from a reservation section 300 which must be adjacent. If DELTA is positive, the segment is 301 extended forwards in the address space, and the reservation must be 302 the next one along. If DELTA is negative, the segment is extended 303 backwards in the address space and the reservation must be the 304 previous one. DELTA must be page aligned. abs(DELTA) must not 305 exceed the size of the reservation segment minus one page, that is, 306 the reservation segment after the operation must be at least one 307 page long. */ 308 extern Bool VG_(am_extend_into_adjacent_reservation_client) 309 ( NSegment* seg, SSizeT delta ); 310 311 /* --- --- --- resizing/move a mapping --- --- --- */ 312 313 /* Let SEG be a client mapping (anonymous or file). This fn extends 314 the mapping forwards only by DELTA bytes, and trashes whatever was 315 in the new area. Fails if SEG is not a single client mapping or if 316 the new area is not accessible to the client. Fails if DELTA is 317 not page aligned. *seg is invalid after a successful return. If 318 *need_discard is True after a successful return, the caller should 319 immediately discard translations from the new area. */ 320 extern Bool VG_(am_extend_map_client)( /*OUT*/Bool* need_discard, 321 NSegment* seg, SizeT delta ); 322 323 /* Remap the old address range to the new address range. Fails if any 324 parameter is not page aligned, if the either size is zero, if any 325 wraparound is implied, if the old address range does not fall 326 entirely within a single segment, if the new address range overlaps 327 with the old one, or if the old address range is not a valid client 328 mapping. If *need_discard is True after a successful return, the 329 caller should immediately discard translations from both specified 330 address ranges. */ 331 extern Bool VG_(am_relocate_nooverlap_client)( /*OUT*/Bool* need_discard, 332 Addr old_addr, SizeT old_len, 333 Addr new_addr, SizeT new_len ); 334 335 //-------------------------------------------------------------- 336 // Valgrind (non-client) thread stacks. V itself runs on such 337 // stacks. The address space manager provides and suitably 338 // protects such stacks. 339 340 #if defined(VGP_ppc32_linux) || defined(VGP_ppc64_linux) 341 # define VG_STACK_GUARD_SZB 65536 // 1 or 16 pages 342 # define VG_STACK_ACTIVE_SZB (4096 * 256) // 1Mb 343 #else 344 # define VG_STACK_GUARD_SZB 8192 // 2 pages 345 # define VG_STACK_ACTIVE_SZB (4096 * 256) // 1Mb 346 #endif 347 348 typedef 349 struct { 350 HChar bytes[VG_STACK_GUARD_SZB 351 + VG_STACK_ACTIVE_SZB 352 + VG_STACK_GUARD_SZB]; 353 } 354 VgStack; 355 356 357 /* Allocate and initialise a VgStack (anonymous client space). 358 Protect the stack active area and the guard areas appropriately. 359 Returns NULL on failure, else the address of the bottom of the 360 stack. On success, also sets *initial_sp to what the stack pointer 361 should be set to. */ 362 363 extern VgStack* VG_(am_alloc_VgStack)( /*OUT*/Addr* initial_sp ); 364 365 /* Figure out how many bytes of the stack's active area have not been 366 used. Used for estimating if we are close to overflowing it. If 367 the free area is larger than 'limit', just return 'limit'. */ 368 extern SizeT VG_(am_get_VgStack_unused_szB)( VgStack* stack, SizeT limit ); 369 370 // DDD: this is ugly 371 #if defined(VGO_darwin) 372 typedef 373 struct { 374 Bool is_added; // Added or removed seg? 375 Addr start; 376 SizeT end; 377 UInt prot; // Not used for removed segs. 378 Off64T offset; // Not used for removed segs. 379 } 380 ChangedSeg; 381 382 extern Bool VG_(get_changed_segments)( 383 const HChar* when, const HChar* where, /*OUT*/ChangedSeg* css, 384 Int css_size, /*OUT*/Int* css_used); 385 #endif 386 387 #endif // __PUB_CORE_ASPACEMGR_H 388 389 /*--------------------------------------------------------------------*/ 390 /*--- end ---*/ 391 /*--------------------------------------------------------------------*/ 392