From 3eb831e0ca5aa3035845fc039c58c6340fd51c31 Mon Sep 17 00:00:00 2001 From: Tristan Gingold Date: Thu, 9 Oct 2014 14:08:07 +0200 Subject: [PATCH] darwin-nat: rewrite darwin_read_write_inferior This is a little bit more efficient. --- gdb/ChangeLog | 7 +++ gdb/darwin-nat.c | 147 +++++++++++++++++++++++++++-------------------- 2 files changed, 93 insertions(+), 61 deletions(-) diff --git a/gdb/ChangeLog b/gdb/ChangeLog index 5a00b5f4b09..269fdcea8b4 100644 --- a/gdb/ChangeLog +++ b/gdb/ChangeLog @@ -1,3 +1,10 @@ +2015-11-23 Tristan Gingold + + * darwin-nat.c (darwin_ptrace): Add a cast to fix warning. + (darwin_resume, cancel_breakpoint, _initialize_darwin_inferior): + Likewise. + (darwin_read_write_inferior): Rewrite using mach_vm_read_overwrite. + 2015-11-19 Don Breazeal * target.c (read_memory_robust): Call read_whatever_is_readable diff --git a/gdb/darwin-nat.c b/gdb/darwin-nat.c index 30e968f7a4c..7ad6b22a41f 100644 --- a/gdb/darwin-nat.c +++ b/gdb/darwin-nat.c @@ -254,8 +254,8 @@ darwin_ptrace (const char *name, if (ret == -1 && errno == 0) ret = 0; - inferior_debug (4, _("ptrace (%s, %d, 0x%x, %d): %d (%s)\n"), - name, pid, arg3, arg4, ret, + inferior_debug (4, _("ptrace (%s, %d, 0x%lx, %d): %d (%s)\n"), + name, pid, (unsigned long) arg3, arg4, ret, (ret != 0) ? safe_strerror (errno) : _("no error")); return ret; } @@ -835,7 +835,7 @@ darwin_resume (ptid_t ptid, int step, enum gdb_signal signal) struct inferior *inf; inferior_debug - (2, _("darwin_resume: pid=%d, tid=0x%x, step=%d, signal=%d\n"), + (2, _("darwin_resume: pid=%d, tid=0x%lx, step=%d, signal=%d\n"), ptid_get_pid (ptid), ptid_get_tid (ptid), step, signal); if (signal == GDB_SIGNAL_0) @@ -1061,8 +1061,8 @@ cancel_breakpoint (ptid_t ptid) pc = regcache_read_pc (regcache) - gdbarch_decr_pc_after_break (gdbarch); if (breakpoint_inserted_here_p (get_regcache_aspace (regcache), pc)) { - inferior_debug (4, "cancel_breakpoint for thread 0x%x\n", - ptid_get_tid (ptid)); + inferior_debug (4, "cancel_breakpoint for thread 0x%lx\n", + (unsigned long) ptid_get_tid (ptid)); /* Back up the PC if necessary. */ if (gdbarch_decr_pc_after_break (gdbarch)) @@ -1810,15 +1810,14 @@ darwin_thread_alive (struct target_ops *ops, ptid_t ptid) If WRADDR is not NULL, write gdb's LEN bytes from WRADDR and copy it to ADDR in inferior task's address space. Return 0 on failure; number of bytes read / writen otherwise. */ + static int darwin_read_write_inferior (task_t task, CORE_ADDR addr, gdb_byte *rdaddr, const gdb_byte *wraddr, ULONGEST length) { kern_return_t kret; - mach_vm_address_t offset = addr & (mach_page_size - 1); - mach_vm_address_t low_address = (mach_vm_address_t) (addr - offset); - mach_vm_size_t aligned_length = (mach_vm_size_t) PAGE_ROUND (offset + length); + mach_vm_size_t res_length = 0; pointer_t copied; mach_msg_type_number_t copy_count; mach_vm_size_t remaining_length; @@ -1828,38 +1827,44 @@ darwin_read_write_inferior (task_t task, CORE_ADDR addr, inferior_debug (8, _("darwin_read_write_inferior(task=0x%x, %s, len=%s)\n"), task, core_addr_to_string (addr), pulongest (length)); - /* Get memory from inferior with page aligned addresses. */ - kret = mach_vm_read (task, low_address, aligned_length, - &copied, ©_count); - if (kret != KERN_SUCCESS) + /* First read. */ + if (rdaddr != NULL) { - inferior_debug - (1, _("darwin_read_write_inferior: mach_vm_read failed at %s: %s"), - core_addr_to_string (addr), mach_error_string (kret)); - return 0; - } + mach_vm_size_t count; - if (rdaddr != NULL) - memcpy (rdaddr, (char *)copied + offset, length); + /* According to target.h(to_xfer_partial), one and only one may be + non-null. */ + gdb_assert (wraddr == NULL); - if (wraddr == NULL) - goto out; + kret = mach_vm_read_overwrite (task, addr, length, + (mach_vm_address_t) rdaddr, &count); + if (kret != KERN_SUCCESS) + { + inferior_debug + (1, _("darwin_read_write_inferior: mach_vm_read failed at %s: %s"), + core_addr_to_string (addr), mach_error_string (kret)); + return 0; + } + return count; + } - memcpy ((char *)copied + offset, wraddr, length); + /* See above. */ + gdb_assert (wraddr != NULL); - /* Do writes atomically. - First check for holes and unwritable memory. */ - for (region_address = low_address, remaining_length = aligned_length; - region_address < low_address + aligned_length; - region_address += region_length, remaining_length -= region_length) + while (length != 0) { + mach_vm_address_t offset = addr & (mach_page_size - 1); + mach_vm_address_t region_address = (mach_vm_address_t) (addr - offset); + mach_vm_size_t aligned_length = + (mach_vm_size_t) PAGE_ROUND (offset + length); vm_region_submap_short_info_data_64_t info; + mach_msg_type_number_t count = VM_REGION_SUBMAP_SHORT_INFO_COUNT_64; + natural_t region_depth = 1000; mach_vm_address_t region_start = region_address; - mach_msg_type_number_t count; - natural_t region_depth; + mach_vm_size_t region_length; + mach_vm_size_t write_length; - region_depth = 100000; - count = VM_REGION_SUBMAP_SHORT_INFO_COUNT_64; + /* Read page protection. */ kret = mach_vm_region_recurse (task, ®ion_start, ®ion_length, ®ion_depth, (vm_region_recurse_info_t) &info, &count); @@ -1870,7 +1875,7 @@ darwin_read_write_inferior (task_t task, CORE_ADDR addr, "mach_vm_region_recurse failed at %s: %s\n"), core_addr_to_string (region_address), mach_error_string (kret)); - goto out; + return res_length; } inferior_debug @@ -1887,56 +1892,76 @@ darwin_read_write_inferior (task_t task, CORE_ADDR addr, core_addr_to_string (region_address), core_addr_to_string (region_start), (unsigned)region_length); - length = 0; - goto out; + return res_length; } /* Adjust the length. */ region_length -= (region_address - region_start); + if (region_length > aligned_length) + region_length = aligned_length; - if (!(info.max_protection & VM_PROT_WRITE)) + /* Make the pages RW. */ + if (!(info.protection & VM_PROT_WRITE)) { - kret = mach_vm_protect - (task, region_address, region_length, - TRUE, info.max_protection | VM_PROT_WRITE | VM_PROT_COPY); + vm_prot_t prot = VM_PROT_READ | VM_PROT_WRITE; + + kret = mach_vm_protect (task, region_address, region_length, + FALSE, prot); if (kret != KERN_SUCCESS) { - warning (_("darwin_read_write_inf: " - "mach_vm_protect max failed at %s: %s"), + prot |= VM_PROT_COPY; + kret = mach_vm_protect (task, region_address, region_length, + FALSE, prot); + } + if (kret != KERN_SUCCESS) + { + warning (_("darwin_read_write_inferior: " + "mach_vm_protect failed at %s " + "(len=0x%lx, prot=0x%x): %s"), core_addr_to_string (region_address), + (unsigned long) region_length, (unsigned) prot, mach_error_string (kret)); - length = 0; - goto out; + return res_length; } } + if (offset + length > region_length) + write_length = region_length - offset; + else + write_length = length; + + /* Write. */ + kret = mach_vm_write (task, addr, (vm_offset_t) wraddr, write_length); + if (kret != KERN_SUCCESS) + { + warning (_("darwin_read_write_inferior: mach_vm_write failed: %s"), + mach_error_string (kret)); + return res_length; + } + + /* Restore page rights. */ if (!(info.protection & VM_PROT_WRITE)) { kret = mach_vm_protect (task, region_address, region_length, - FALSE, info.protection | VM_PROT_WRITE); + FALSE, info.protection); if (kret != KERN_SUCCESS) { - warning (_("darwin_read_write_inf: " - "mach_vm_protect failed at %s (len=0x%lx): %s"), + warning (_("darwin_read_write_inferior: " + "mach_vm_protect restore failed at %s " + "(len=0x%lx): %s"), core_addr_to_string (region_address), - (unsigned long)region_length, mach_error_string (kret)); - length = 0; - goto out; + (unsigned long) region_length, + mach_error_string (kret)); } } - } - - kret = mach_vm_write (task, low_address, copied, aligned_length); - if (kret != KERN_SUCCESS) - { - warning (_("darwin_read_write_inferior: mach_vm_write failed: %s"), - mach_error_string (kret)); - length = 0; + addr += write_length; + wraddr += write_length; + res_length += write_length; + length -= write_length; } -out: - mach_vm_deallocate (mach_task_self (), copied, copy_count); - return length; + + return res_length; } /* Read LENGTH bytes at offset ADDR of task_dyld_info for TASK, and copy them @@ -2170,8 +2195,8 @@ _initialize_darwin_inferior (void) add_target (darwin_ops); - inferior_debug (2, _("GDB task: 0x%lx, pid: %d\n"), mach_task_self (), - getpid ()); + inferior_debug (2, _("GDB task: 0x%lx, pid: %d\n"), + (unsigned long) mach_task_self (), getpid ()); add_setshow_zuinteger_cmd ("darwin", class_obscure, &darwin_debug_flag, _("\ -- 2.30.2