return client_SP;
}
-
-/* Allocate the client data segment. It is an expandable anonymous mapping
- abutting a 1-page reservation. The data segment starts at VG_(brk_base)
- and runs up to VG_(brk_limit). None of these two values have to be
- page-aligned.
- Reservation segment is used to protect the data segment merging with
- a pre-existing segment. This should be no problem because address space
- manager ensures that requests for client address space are satisfied from
- the highest available addresses. However when memory is low, data segment
- can meet with mmap'ed objects and the reservation segment separates these.
- The page that contains VG_(brk_base) is already allocated by the program's
- loaded data segment. The brk syscall wrapper handles this special case.
- See the brk syscall wrapper for more information. */
-static void setup_client_dataseg(SizeT initial_size)
-{
- Bool ok;
- SysRes sres;
- Addr anon_start = VG_PGROUNDUP(VG_(brk_base));
- SizeT anon_size = VG_PGROUNDUP(initial_size);
- Addr resvn_start = anon_start + anon_size;
- SizeT resvn_size = VKI_PAGE_SIZE;
- const NSegment *seg;
- UInt prot;
-
- vg_assert(VG_IS_PAGE_ALIGNED(anon_size));
- vg_assert(VG_IS_PAGE_ALIGNED(resvn_size));
- vg_assert(VG_IS_PAGE_ALIGNED(anon_start));
- vg_assert(VG_IS_PAGE_ALIGNED(resvn_start));
-
- /* Stay sane (because there's been no brk activity yet). */
- vg_assert(VG_(brk_base) == VG_(brk_limit));
-
- /* Find the loaded data segment and remember its protection. */
- seg = VG_(am_find_nsegment)(VG_(brk_base) - 1);
- vg_assert(seg);
- prot = (seg->hasR ? VKI_PROT_READ : 0)
- | (seg->hasW ? VKI_PROT_WRITE : 0)
- | (seg->hasX ? VKI_PROT_EXEC : 0);
-
- /* Try to create the data segment and associated reservation where
- VG_(brk_base) says. */
- ok = VG_(am_create_reservation)(resvn_start, resvn_size, SmLower, anon_size);
- if (!ok) {
- /* That didn't work, we're hosed. */
- VG_(printf)("valgrind: cannot initialize a brk segment\n");
- VG_(exit)(1);
- /*NOTREACHED*/
- }
- vg_assert(ok);
-
- /* Map the data segment. */
- sres = VG_(am_mmap_anon_fixed_client)(anon_start, anon_size, prot);
- vg_assert(!sr_isError(sres));
- vg_assert(sr_Res(sres) == anon_start);
-}
-
-
/*====================================================================*/
/*=== TOP-LEVEL: VG_(setup_client_initial_image) ===*/
/*====================================================================*/
iifii.clstack_max_size);
}
- //--------------------------------------------------------------
- // Setup client data (brk) segment. Initially segment at least
- // 1 MB and at most 8 MB large which abuts a 1-page reservation.
- // p: load_client() [for 'info' and hence VG_(brk_base)]
- //--------------------------------------------------------------
- {
- SizeT m1 = 1024 * 1024;
- SizeT m8 = 8 * m1;
- SizeT dseg_max_size = VG_(client_rlimit_data).rlim_cur;
- VG_(debugLog)(1, "initimg", "Setup client data (brk) segment at %#lx\n",
- VG_(brk_base));
- if (dseg_max_size < m1)
- dseg_max_size = m1;
- if (dseg_max_size > m8)
- dseg_max_size = m8;
- dseg_max_size = VG_PGROUNDUP(dseg_max_size);
-
- setup_client_dataseg(dseg_max_size);
- }
-
+ /* Initial data (brk) segment is setup on demand, when a first brk() syscall
+ is made. It cannot be established now because it would conflict with
+ a temporary stack which ld.so.1 (when executed directly) uses for loading
+ the target dynamic executable. See PRE(sys_brk) in syswrap-solaris.c. */
return iifii;
}
void VG_(ii_finalise_image)(IIFinaliseImageInfo iifii)
{
ThreadArchState *arch = &VG_(threads)[1].arch;
- const NSegment *seg;
# if defined(VGA_x86)
vg_assert(0 == sizeof(VexGuestX86State) % LibVEX_GUEST_STATE_ALIGN);
VG_TRACK(post_reg_write, Vg_CoreStartup, 1/*tid*/, 0/*offset*/,
sizeof(VexGuestArchState));
- /* Tell the tool about the client data segment and then kill it which will
- make it inaccessible/unaddressable. */
- seg = VG_(am_find_nsegment)(VG_PGROUNDUP(VG_(brk_base)));
- vg_assert(seg);
- vg_assert(seg->kind == SkAnonC);
- VG_TRACK(new_mem_brk, VG_(brk_base), seg->end + 1 - VG_(brk_base),
- 1/*tid*/);
- VG_TRACK(die_mem_brk, VG_(brk_base), seg->end + 1 - VG_(brk_base));
+ /* Make inaccessible/unaddressable the end of the client data segment.
+ See PRE(sys_brk) in syswrap-solaris.c for details. Nothing to do in
+ case VG_(brk_base) starts on the beginning of a free page. */
+ const NSegment *seg = VG_(am_find_nsegment)(VG_(brk_base));
+ if (seg != NULL) {
+ vg_assert((seg->kind == SkFileC) || (seg->kind == SkAnonC));
+ VG_TRACK(new_mem_brk, VG_(brk_base), seg->end + 1 - VG_(brk_base),
+ 1 /* tid */);
+ VG_TRACK(die_mem_brk, VG_(brk_base), seg->end + 1 - VG_(brk_base));
+ }
}
#endif // defined(VGO_solaris)
PRE_REG_READ0(long, "time");
}
-/* Data segment for brk (heap).
- Initial data segment is established during image initialization
- (initimg-solaris.c). Notable facts:
+/* Data segment for brk (heap). It is an expandable anonymous mapping
+ abutting a 1-page reservation. The data segment starts at VG_(brk_base)
+ and runs up to VG_(brk_limit). None of these two values have to be
+ page-aligned. Initial data segment is established on demand here (see
+ initimg-solaris.c for rationale).
+ Notable facts:
- VG_(brk_base) is not page aligned; does not move
- VG_(brk_limit) moves between [VG_(brk_base), data segment end]
- data segment end is always page aligned
- right after data segment end is 1-page reservation
- | heap |
+ | heap | 1 page
+------+------+--------------+-------+
| BSS | anon | anon | resvn |
+------+------+--------------+-------+
VG_(brk_base) -- not page aligned -- does not move
Because VG_(brk_base) is not page-aligned and is initially located within
- pre-established data segment, special care has to be taken in the code below
- to handle this feature.
-*/
+ pre-established BSS (data) segment, special care has to be taken in the code
+ below to handle this feature.
+
+ Reservation segment is used to protect the data segment merging with
+ a pre-existing segment. This should be no problem because address space
+ manager ensures that requests for client address space are satisfied from
+ the highest available addresses. However when memory is low, data segment
+ can meet with mmap'ed objects and the reservation segment separates these.
+ The page that contains VG_(brk_base) is already allocated by the program's
+ loaded data segment. The brk syscall wrapper handles this special case. */
+
+/* Establishes initial data segment for brk (heap). */
+static Bool setup_client_dataseg(SizeT initial_size, ThreadId tid)
+{
+ Addr anon_start = VG_PGROUNDUP(VG_(brk_base));
+ SizeT anon_size = VG_PGROUNDUP(initial_size);
+ Addr resvn_start = anon_start + anon_size;
+ SizeT resvn_size = VKI_PAGE_SIZE;
+
+ vg_assert(VG_IS_PAGE_ALIGNED(anon_size));
+ vg_assert(VG_IS_PAGE_ALIGNED(resvn_size));
+ vg_assert(VG_IS_PAGE_ALIGNED(anon_start));
+ vg_assert(VG_IS_PAGE_ALIGNED(resvn_start));
+ vg_assert(VG_(brk_base) == VG_(brk_limit));
+
+ /* Find the loaded data segment and remember its protection. */
+ const NSegment *seg = VG_(am_find_nsegment)(VG_(brk_base) - 1);
+ vg_assert(seg != NULL);
+ UInt prot = (seg->hasR ? VKI_PROT_READ : 0)
+ | (seg->hasW ? VKI_PROT_WRITE : 0)
+ | (seg->hasX ? VKI_PROT_EXEC : 0);
+
+ /* Try to create the data segment and associated reservation where
+ VG_(brk_base) says. */
+ Bool ok = VG_(am_create_reservation)(resvn_start, resvn_size, SmLower,
+ anon_size);
+ if (!ok) {
+ /* That didn't work, we're hosed. */
+ return False;
+ }
+
+ /* Map the data segment. */
+ SysRes sres = VG_(am_mmap_anon_fixed_client)(anon_start, anon_size, prot);
+ vg_assert(!sr_isError(sres));
+ vg_assert(sr_Res(sres) == anon_start);
+
+ /* Tell the tool about the client data segment and then kill it which will
+ make it initially inaccessible/unaddressable. */
+ seg = VG_(am_find_nsegment)(anon_start);
+ vg_assert(seg != NULL);
+ vg_assert(seg->kind == SkAnonC);
+ VG_TRACK(new_mem_brk, VG_(brk_base), seg->end + 1 - VG_(brk_base), tid);
+ VG_TRACK(die_mem_brk, VG_(brk_base), seg->end + 1 - VG_(brk_base));
+ return True;
+}
+
+static Bool brk_segment_established = False;
PRE(sys_brk)
{
PRINT("sys_brk ( %#lx )", ARG1);
PRE_REG_READ1(unsigned long, "brk", vki_caddr_t, end_data_segment);
- if (!new_brk) {
+ if (new_brk == 0) {
/* brk(0) - specific to Solaris 11 only. */
SET_STATUS_Success(old_brk_limit);
return;
return;
}
+ if (!brk_segment_established) {
+ /* Stay sane (because there should have been no brk activity yet). */
+ vg_assert(VG_(brk_base) == VG_(brk_limit));
+
+ /* Establish an initial data segment for brk (heap).
+ Initially at least 1 MB and at most 8 MB large. */
+ SizeT m1 = 1024 * 1024;
+ SizeT m8 = 8 * m1;
+ SizeT dseg_max_size = VG_(client_rlimit_data).rlim_cur;
+ VG_(debugLog)(1, "syswrap-solaris", "Setup client data (brk) segment "
+ "at %#lx\n", VG_(brk_base));
+ if (dseg_max_size < m1)
+ dseg_max_size = m1;
+ if (dseg_max_size > m8)
+ dseg_max_size = m8;
+ dseg_max_size = VG_PGROUNDUP(dseg_max_size);
+
+ if (!setup_client_dataseg(dseg_max_size, tid)) {
+ VG_(umsg)("Cannot map memory to initialize brk segment in thread #%d "
+ "at %#lx\n", tid, VG_(brk_base));
+ SET_STATUS_Failure(VKI_ENOMEM);
+ return;
+ }
+
+ brk_segment_established = True;
+ }
+
if (new_brk < old_brk_limit) {
/* Shrinking the data segment. Be lazy and don't munmap the excess
area. */
projects / thirdparty / valgrind.git / commitdiff
