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Diffstat (limited to 'src/pal/src/libunwind/src/x86_64/Ginit.c')
-rw-r--r--src/pal/src/libunwind/src/x86_64/Ginit.c342
1 files changed, 342 insertions, 0 deletions
diff --git a/src/pal/src/libunwind/src/x86_64/Ginit.c b/src/pal/src/libunwind/src/x86_64/Ginit.c
new file mode 100644
index 0000000000..2a84a1eec7
--- /dev/null
+++ b/src/pal/src/libunwind/src/x86_64/Ginit.c
@@ -0,0 +1,342 @@
+/* libunwind - a platform-independent unwind library
+ Copyright (C) 2002 Hewlett-Packard Co
+ Copyright (C) 2007 David Mosberger-Tang
+ Contributed by David Mosberger-Tang <dmosberger@gmail.com>
+
+ Modified for x86_64 by Max Asbock <masbock@us.ibm.com>
+
+This file is part of libunwind.
+
+Permission is hereby granted, free of charge, to any person obtaining
+a copy of this software and associated documentation files (the
+"Software"), to deal in the Software without restriction, including
+without limitation the rights to use, copy, modify, merge, publish,
+distribute, sublicense, and/or sell copies of the Software, and to
+permit persons to whom the Software is furnished to do so, subject to
+the following conditions:
+
+The above copyright notice and this permission notice shall be
+included in all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include <errno.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/mman.h>
+#include <sys/syscall.h>
+
+#include "unwind_i.h"
+
+#ifdef UNW_REMOTE_ONLY
+
+/* unw_local_addr_space is a NULL pointer in this case. */
+unw_addr_space_t unw_local_addr_space;
+
+#else /* !UNW_REMOTE_ONLY */
+
+static struct unw_addr_space local_addr_space;
+
+unw_addr_space_t unw_local_addr_space = &local_addr_space;
+
+HIDDEN unw_dyn_info_list_t _U_dyn_info_list;
+
+/* XXX fix me: there is currently no way to locate the dyn-info list
+ by a remote unwinder. On ia64, this is done via a special
+ unwind-table entry. Perhaps something similar can be done with
+ DWARF2 unwind info. */
+
+static void
+put_unwind_info (unw_addr_space_t as, unw_proc_info_t *proc_info, void *arg)
+{
+ /* it's a no-op */
+}
+
+static int
+get_dyn_info_list_addr (unw_addr_space_t as, unw_word_t *dyn_info_list_addr,
+ void *arg)
+{
+ *dyn_info_list_addr = (unw_word_t) &_U_dyn_info_list;
+ return 0;
+}
+
+#define PAGE_SIZE 4096
+#define PAGE_START(a) ((a) & ~(PAGE_SIZE-1))
+
+static int mem_validate_pipe[2] = {-1, -1};
+
+static inline void
+open_pipe (void)
+{
+ /* ignore errors for closing invalid fd's */
+ close (mem_validate_pipe[0]);
+ close (mem_validate_pipe[1]);
+
+ pipe2 (mem_validate_pipe, O_CLOEXEC | O_NONBLOCK);
+}
+
+ALWAYS_INLINE
+static int
+write_validate (void *addr)
+{
+ int ret = -1;
+ ssize_t bytes = 0;
+
+ do
+ {
+ char buf;
+ bytes = read (mem_validate_pipe[0], &buf, 1);
+ }
+ while ( errno == EINTR );
+
+ int valid_read = (bytes > 0 || errno == EAGAIN || errno == EWOULDBLOCK);
+ if (!valid_read)
+ {
+ // re-open closed pipe
+ open_pipe ();
+ }
+
+ do
+ {
+ /* use syscall insteadof write() so that ASAN does not complain */
+ ret = syscall (SYS_write, mem_validate_pipe[1], addr, 1);
+ }
+ while ( errno == EINTR );
+
+ return ret;
+}
+
+static int (*mem_validate_func) (void *addr, size_t len);
+static int msync_validate (void *addr, size_t len)
+{
+ if (msync (addr, len, MS_ASYNC) != 0)
+ {
+ return -1;
+ }
+
+ return write_validate (addr);
+}
+
+#ifdef HAVE_MINCORE
+static int mincore_validate (void *addr, size_t len)
+{
+ unsigned char mvec[2]; /* Unaligned access may cross page boundary */
+ size_t i;
+
+ /* mincore could fail with EAGAIN but we conservatively return -1
+ instead of looping. */
+ if (mincore (addr, len, mvec) != 0)
+ {
+ return -1;
+ }
+
+ for (i = 0; i < (len + PAGE_SIZE - 1) / PAGE_SIZE; i++)
+ {
+ if (!(mvec[i] & 1)) return -1;
+ }
+
+ return write_validate (addr);
+}
+#endif
+
+/* Initialise memory validation method. On linux kernels <2.6.21,
+ mincore() returns incorrect value for MAP_PRIVATE mappings,
+ such as stacks. If mincore() was available at compile time,
+ check if we can actually use it. If not, use msync() instead. */
+HIDDEN void
+tdep_init_mem_validate (void)
+{
+ open_pipe ();
+
+#ifdef HAVE_MINCORE
+ unsigned char present = 1;
+ unw_word_t addr = PAGE_START((unw_word_t)&present);
+ unsigned char mvec[1];
+ int ret;
+ while ((ret = mincore ((void*)addr, PAGE_SIZE, mvec)) == -1 &&
+ errno == EAGAIN) {}
+ if (ret == 0 && (mvec[0] & 1))
+ {
+ Debug(1, "using mincore to validate memory\n");
+ mem_validate_func = mincore_validate;
+ }
+ else
+#endif
+ {
+ Debug(1, "using msync to validate memory\n");
+ mem_validate_func = msync_validate;
+ }
+}
+
+/* Cache of already validated addresses */
+#define NLGA 4
+static unw_word_t last_good_addr[NLGA];
+static int lga_victim;
+
+static int
+validate_mem (unw_word_t addr)
+{
+ int i, victim;
+ size_t len;
+
+ if (PAGE_START(addr + sizeof (unw_word_t) - 1) == PAGE_START(addr))
+ len = PAGE_SIZE;
+ else
+ len = PAGE_SIZE * 2;
+
+ addr = PAGE_START(addr);
+
+ if (addr == 0)
+ return -1;
+
+ for (i = 0; i < NLGA; i++)
+ {
+ if (last_good_addr[i] && (addr == last_good_addr[i]))
+ return 0;
+ }
+
+ if (mem_validate_func ((void *) addr, len) == -1)
+ return -1;
+
+ victim = lga_victim;
+ for (i = 0; i < NLGA; i++) {
+ if (!last_good_addr[victim]) {
+ last_good_addr[victim++] = addr;
+ return 0;
+ }
+ victim = (victim + 1) % NLGA;
+ }
+
+ /* All slots full. Evict the victim. */
+ last_good_addr[victim] = addr;
+ victim = (victim + 1) % NLGA;
+ lga_victim = victim;
+
+ return 0;
+}
+
+static int
+access_mem (unw_addr_space_t as, unw_word_t addr, unw_word_t *val, int write,
+ void *arg)
+{
+ if (unlikely (write))
+ {
+ Debug (16, "mem[%016lx] <- %lx\n", addr, *val);
+ *(unw_word_t *) addr = *val;
+ }
+ else
+ {
+ /* validate address */
+ const struct cursor *c = (const struct cursor *)arg;
+ if (likely (c != NULL) && unlikely (c->validate)
+ && unlikely (validate_mem (addr))) {
+ Debug (16, "mem[%016lx] -> invalid\n", addr);
+ return -1;
+ }
+ *val = *(unw_word_t *) addr;
+ Debug (16, "mem[%016lx] -> %lx\n", addr, *val);
+ }
+ return 0;
+}
+
+static int
+access_reg (unw_addr_space_t as, unw_regnum_t reg, unw_word_t *val, int write,
+ void *arg)
+{
+ unw_word_t *addr;
+ ucontext_t *uc = ((struct cursor *)arg)->uc;
+
+ if (unw_is_fpreg (reg))
+ goto badreg;
+
+ if (!(addr = x86_64_r_uc_addr (uc, reg)))
+ goto badreg;
+
+ if (write)
+ {
+ *(unw_word_t *) addr = *val;
+ Debug (12, "%s <- 0x%016lx\n", unw_regname (reg), *val);
+ }
+ else
+ {
+ *val = *(unw_word_t *) addr;
+ Debug (12, "%s -> 0x%016lx\n", unw_regname (reg), *val);
+ }
+ return 0;
+
+ badreg:
+ Debug (1, "bad register number %u\n", reg);
+ return -UNW_EBADREG;
+}
+
+static int
+access_fpreg (unw_addr_space_t as, unw_regnum_t reg, unw_fpreg_t *val,
+ int write, void *arg)
+{
+ ucontext_t *uc = ((struct cursor *)arg)->uc;
+ unw_fpreg_t *addr;
+
+ if (!unw_is_fpreg (reg))
+ goto badreg;
+
+ if (!(addr = x86_64_r_uc_addr (uc, reg)))
+ goto badreg;
+
+ if (write)
+ {
+ Debug (12, "%s <- %08lx.%08lx.%08lx\n", unw_regname (reg),
+ ((long *)val)[0], ((long *)val)[1], ((long *)val)[2]);
+ *(unw_fpreg_t *) addr = *val;
+ }
+ else
+ {
+ *val = *(unw_fpreg_t *) addr;
+ Debug (12, "%s -> %08lx.%08lx.%08lx\n", unw_regname (reg),
+ ((long *)val)[0], ((long *)val)[1], ((long *)val)[2]);
+ }
+ return 0;
+
+ badreg:
+ Debug (1, "bad register number %u\n", reg);
+ /* attempt to access a non-preserved register */
+ return -UNW_EBADREG;
+}
+
+static int
+get_static_proc_name (unw_addr_space_t as, unw_word_t ip,
+ char *buf, size_t buf_len, unw_word_t *offp,
+ void *arg)
+{
+ return _Uelf64_get_proc_name (as, getpid (), ip, buf, buf_len, offp);
+}
+
+HIDDEN void
+x86_64_local_addr_space_init (void)
+{
+ memset (&local_addr_space, 0, sizeof (local_addr_space));
+ local_addr_space.caching_policy = UNWI_DEFAULT_CACHING_POLICY;
+ local_addr_space.acc.find_proc_info = dwarf_find_proc_info;
+ local_addr_space.acc.put_unwind_info = put_unwind_info;
+ local_addr_space.acc.get_dyn_info_list_addr = get_dyn_info_list_addr;
+ local_addr_space.acc.access_mem = access_mem;
+ local_addr_space.acc.access_reg = access_reg;
+ local_addr_space.acc.access_fpreg = access_fpreg;
+ local_addr_space.acc.resume = x86_64_local_resume;
+ local_addr_space.acc.get_proc_name = get_static_proc_name;
+ unw_flush_cache (&local_addr_space, 0, 0);
+
+ memset (last_good_addr, 0, sizeof (unw_word_t) * NLGA);
+ lga_victim = 0;
+}
+
+#endif /* !UNW_REMOTE_ONLY */
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