1 //===-- MachVMRegion.cpp ----------------------------------------*- C++ -*-===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 //  Created by Greg Clayton on 6/26/07.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #include "MachVMRegion.h"
15 #include <mach/mach_vm.h>
16 #include "DNBLog.h"
17 #include <assert.h>
18 
19 MachVMRegion::MachVMRegion(task_t task) :
20     m_task(task),
21     m_addr(INVALID_NUB_ADDRESS),
22     m_err(),
23     m_start(INVALID_NUB_ADDRESS),
24     m_size(0),
25     m_depth(-1),
26     m_curr_protection(0),
27     m_protection_addr(INVALID_NUB_ADDRESS),
28     m_protection_size(0)
29 {
30     memset(&m_data, 0, sizeof(m_data));
31 }
32 
33 MachVMRegion::~MachVMRegion()
34 {
35     // Restore any original protections and clear our vars
36     Clear();
37 }
38 
39 void
40 MachVMRegion::Clear()
41 {
42     RestoreProtections();
43     m_addr = INVALID_NUB_ADDRESS;
44     m_err.Clear();
45     m_start = INVALID_NUB_ADDRESS;
46     m_size = 0;
47     m_depth = -1;
48     memset(&m_data, 0, sizeof(m_data));
49     m_curr_protection = 0;
50     m_protection_addr = INVALID_NUB_ADDRESS;
51     m_protection_size = 0;
52 }
53 
54 bool
55 MachVMRegion::SetProtections(mach_vm_address_t addr, mach_vm_size_t size, vm_prot_t prot)
56 {
57     if (ContainsAddress(addr))
58     {
59         mach_vm_size_t prot_size = size;
60         mach_vm_address_t end_addr = EndAddress();
61         if (prot_size > (end_addr - addr))
62             prot_size = end_addr - addr;
63 
64         if (prot_size > 0)
65         {
66             if (prot == (m_curr_protection & VM_PROT_ALL))
67             {
68                 DNBLogThreadedIf(LOG_MEMORY_PROTECTIONS | LOG_VERBOSE, "MachVMRegion::%s: protections (%u) already sufficient for task 0x%4.4x at address 0x%8.8llx) ", __FUNCTION__, prot, m_task, (uint64_t)addr);
69                 // Protections are already set as requested...
70                 return true;
71             }
72             else
73             {
74                 m_err = ::mach_vm_protect (m_task, addr, prot_size, 0, prot);
75                 if (DNBLogCheckLogBit(LOG_MEMORY_PROTECTIONS))
76                     m_err.LogThreaded("::mach_vm_protect ( task = 0x%4.4x, addr = 0x%8.8llx, size = %llu, set_max = %i, prot = %u )", m_task, (uint64_t)addr, (uint64_t)prot_size, 0, prot);
77                 if (m_err.Fail())
78                 {
79                     // Try again with the ability to create a copy on write region
80                     m_err = ::mach_vm_protect (m_task, addr, prot_size, 0, prot | VM_PROT_COPY);
81                     if (DNBLogCheckLogBit(LOG_MEMORY_PROTECTIONS) || m_err.Fail())
82                         m_err.LogThreaded("::mach_vm_protect ( task = 0x%4.4x, addr = 0x%8.8llx, size = %llu, set_max = %i, prot = %u )", m_task, (uint64_t)addr, (uint64_t)prot_size, 0, prot | VM_PROT_COPY);
83                 }
84                 if (m_err.Success())
85                 {
86                     m_curr_protection = prot;
87                     m_protection_addr = addr;
88                     m_protection_size = prot_size;
89                     return true;
90                 }
91             }
92         }
93         else
94         {
95             DNBLogThreadedIf(LOG_MEMORY_PROTECTIONS | LOG_VERBOSE, "%s: Zero size for task 0x%4.4x at address 0x%8.8llx) ", __FUNCTION__, m_task, (uint64_t)addr);
96         }
97     }
98     return false;
99 }
100 
101 bool
102 MachVMRegion::RestoreProtections()
103 {
104     if (m_curr_protection != m_data.protection && m_protection_size > 0)
105     {
106         m_err = ::mach_vm_protect (m_task, m_protection_addr, m_protection_size, 0, m_data.protection);
107         if (DNBLogCheckLogBit(LOG_MEMORY_PROTECTIONS) || m_err.Fail())
108             m_err.LogThreaded("::mach_vm_protect ( task = 0x%4.4x, addr = 0x%8.8llx, size = %llu, set_max = %i, prot = %u )", m_task, (uint64_t)m_protection_addr, (uint64_t)m_protection_size, 0, m_data.protection);
109         if (m_err.Success())
110         {
111             m_protection_size = 0;
112             m_protection_addr = INVALID_NUB_ADDRESS;
113             m_curr_protection = m_data.protection;
114             return true;
115         }
116     }
117     else
118     {
119         m_err.Clear();
120         return true;
121     }
122 
123     return false;
124 }
125 
126 bool
127 MachVMRegion::GetRegionForAddress(nub_addr_t addr)
128 {
129     // Restore any original protections and clear our vars
130     Clear();
131     m_addr = addr;
132     m_start = addr;
133     m_depth = 1024;
134     mach_msg_type_number_t info_size = kRegionInfoSize;
135     assert(sizeof(info_size) == 4);
136     m_err = ::mach_vm_region_recurse (m_task, &m_start, &m_size, &m_depth, (vm_region_recurse_info_t)&m_data, &info_size);
137     const bool log_protections = DNBLogCheckLogBit(LOG_MEMORY_PROTECTIONS);
138     if (m_err.Success())
139     {
140         if ((addr < m_start) || (addr >= (m_start + m_size)))
141         {
142             m_err.SetErrorString("no region for address");
143             m_err.SetError(-1, DNBError::Generic);
144             if (log_protections)
145                 m_err.LogThreaded("::mach_vm_region_recurse ( task = 0x%4.4x, address => 0x%8.8llx, size => %llu, nesting_depth => %d, info => %p, infoCnt => %d) addr = 0x%8.8llx not in range [0x%8.8llx - 0x%8.8llx)",
146                                   m_task, (uint64_t)m_start, (uint64_t)m_size, m_depth, &m_data, info_size, (uint64_t)addr, (uint64_t)m_start, (uint64_t)m_start + m_size);
147             return false;
148         }
149     }
150 
151     if (log_protections || m_err.Fail())
152         m_err.LogThreaded("::mach_vm_region_recurse ( task = 0x%4.4x, address => 0x%8.8llx, size => %llu, nesting_depth => %d, info => %p, infoCnt => %d) addr = 0x%8.8llx ", m_task, (uint64_t)m_start, (uint64_t)m_size, m_depth, &m_data, info_size, (uint64_t)addr);
153     if (m_err.Fail())
154     {
155         return false;
156     }
157     else
158     {
159         if (log_protections)
160         {
161             DNBLogThreaded("info = { prot = %u, "
162                              "max_prot = %u, "
163                              "inheritance = 0x%8.8x, "
164                              "offset = 0x%8.8llx, "
165                              "user_tag = 0x%8.8x, "
166                              "ref_count = %u, "
167                              "shadow_depth = %u, "
168                              "ext_pager = %u, "
169                              "share_mode = %u, "
170                              "is_submap = %d, "
171                              "behavior = %d, "
172                              "object_id = 0x%8.8x, "
173                              "user_wired_count = 0x%4.4x }",
174                              m_data.protection,
175                              m_data.max_protection,
176                              m_data.inheritance,
177                              (uint64_t)m_data.offset,
178                              m_data.user_tag,
179                              m_data.ref_count,
180                              m_data.shadow_depth,
181                              m_data.external_pager,
182                              m_data.share_mode,
183                              m_data.is_submap,
184                              m_data.behavior,
185                              m_data.object_id,
186                              m_data.user_wired_count);
187         }
188     }
189 
190     m_curr_protection = m_data.protection;
191 
192     return true;
193 }
194 
195 uint32_t
196 MachVMRegion::GetDNBPermissions () const
197 {
198     if (m_addr == INVALID_NUB_ADDRESS || m_start == INVALID_NUB_ADDRESS || m_size == 0)
199       return 0;
200     uint32_t dnb_permissions = 0;
201 
202     if ((m_data.protection & VM_PROT_READ) == VM_PROT_READ)
203         dnb_permissions |= eMemoryPermissionsReadable;
204     if ((m_data.protection & VM_PROT_WRITE) == VM_PROT_WRITE)
205         dnb_permissions |= eMemoryPermissionsWritable;
206     if ((m_data.protection & VM_PROT_EXECUTE) == VM_PROT_EXECUTE)
207         dnb_permissions |= eMemoryPermissionsExecutable;
208     return dnb_permissions;
209 }
210