diff options
Diffstat (limited to 'src/third_party/unwind/dist/src/s390x/Ginit.c')
-rw-r--r-- | src/third_party/unwind/dist/src/s390x/Ginit.c | 366 |
1 files changed, 366 insertions, 0 deletions
diff --git a/src/third_party/unwind/dist/src/s390x/Ginit.c b/src/third_party/unwind/dist/src/s390x/Ginit.c new file mode 100644 index 00000000000..f0886ac9337 --- /dev/null +++ b/src/third_party/unwind/dist/src/s390x/Ginit.c @@ -0,0 +1,366 @@ +/* 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> + Modified for s390x by Michael Munday <mike.munday@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; + +static inline void * +uc_addr (ucontext_t *uc, int reg) +{ + if (reg >= UNW_S390X_R0 && reg <= UNW_S390X_R15) + return &uc->uc_mcontext.gregs[reg - UNW_S390X_R0]; + if (reg >= UNW_S390X_F0 && reg <= UNW_S390X_F15) + return &uc->uc_mcontext.fpregs.fprs[reg - UNW_S390X_F0]; + if (reg == UNW_S390X_IP) + return &uc->uc_mcontext.psw.addr; + + return NULL; +} + +# ifdef UNW_LOCAL_ONLY + +HIDDEN void * +tdep_uc_addr (ucontext_t *uc, int reg) +{ + return uc_addr (uc, reg); +} + +# endif /* UNW_LOCAL_ONLY */ + +/* 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 = 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 = 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 +s390x_local_addr_space_init (void) +{ + memset (&local_addr_space, 0, sizeof (local_addr_space)); + local_addr_space.caching_policy = UNW_CACHE_GLOBAL; + 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 = s390x_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 */ |