src/sim/process.hh

   1 /*
   2  * Copyright (c) 2014 Advanced Micro Devices, Inc.
   3  * Copyright (c) 2001-2005 The Regents of The University of Michigan
   4  * All rights reserved.
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions are
   8  * met: redistributions of source code must retain the above copyright
   9  * notice, this list of conditions and the following disclaimer;
  10  * redistributions in binary form must reproduce the above copyright
  11  * notice, this list of conditions and the following disclaimer in the
  12  * documentation and/or other materials provided with the distribution;
  13  * neither the name of the copyright holders nor the names of its
  14  * contributors may be used to endorse or promote products derived from
  15  * this software without specific prior written permission.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  18  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  19  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  20  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  21  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  22  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  23  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  24  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  25  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  26  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  27  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  28  *
  29  * Authors: Nathan Binkert
  30  *          Steve Reinhardt
  31  */
  32
  33 #ifndef __PROCESS_HH__
  34 #define __PROCESS_HH__
  35
  36 #include <array>
  37 #include <string>
  38 #include <vector>
  39
  40 #include "arch/registers.hh"
  41 #include "base/statistics.hh"
  42 #include "base/types.hh"
  43 #include "config/the_isa.hh"
  44 #include "mem/se_translating_port_proxy.hh"
  45 #include "sim/fd_entry.hh"
  46 #include "sim/sim_object.hh"
  47 #include "sim/syscallreturn.hh"
  48
  49 class PageTable;
  50 struct ProcessParams;
  51 struct LiveProcessParams;
  52 class SyscallDesc;
  53 class System;
  54 class ThreadContext;
  55 class EmulatedDriver;
  56
  57 template<class IntType>
  58 struct AuxVector
  59 {
  60     IntType a_type;
  61     IntType a_val;
  62
  63     AuxVector()
  64     {}
  65
  66     AuxVector(IntType type, IntType val);
  67 };
  68
  69 class Process : public SimObject
  70 {
  71   public:
  72
  73     /// Pointer to object representing the system this process is
  74     /// running on.
  75     System *system;
  76
  77     // thread contexts associated with this process
  78     std::vector<ContextID> contextIds;
  79
  80     // number of CPUs (esxec contexts, really) assigned to this process.
  81     unsigned int numCpus() { return contextIds.size(); }
  82
  83     // record of blocked context
  84     struct WaitRec
  85     {
  86         Addr waitChan;
  87         ThreadContext *waitingContext;
  88
  89         WaitRec(Addr chan, ThreadContext *ctx)
  90             : waitChan(chan), waitingContext(ctx)
  91         {       }
  92     };
  93
  94     // list of all blocked contexts
  95     std::list<WaitRec> waitList;
  96
  97     Addr brk_point;             // top of the data segment
  98
  99     Addr stack_base;            // stack segment base (highest address)
 100     unsigned stack_size;        // initial stack size
 101     Addr stack_min;             // lowest address accessed on the stack
 102
 103     // The maximum size allowed for the stack.
 104     Addr max_stack_size;
 105
 106     // addr to use for next stack region (for multithreaded apps)
 107     Addr next_thread_stack_base;
 108
 109     // Base of region for mmaps (when user doesn't specify an address).
 110     Addr mmap_end;
 111
 112     // Does mmap region grow upward or downward from mmap_end?  Most
 113     // platforms grow downward, but a few (such as Alpha) grow upward
 114     // instead, so they can override thie method to return false.
 115     virtual bool mmapGrowsDown() const { return true; }
 116
 117     // Base of region for nxm data
 118     Addr nxm_start;
 119     Addr nxm_end;
 120
 121     Stats::Scalar num_syscalls;       // number of syscalls executed
 122
 123   protected:
 124     // constructor
 125     Process(ProcessParams *params);
 126
 127     void initState() override;
 128
 129     DrainState drain() override;
 130
 131   public:
 132
 133     //This id is assigned by m5 and is used to keep process' tlb entries
 134     //separated.
 135     uint64_t M5_pid;
 136
 137     // flag for using architecture specific page table
 138     bool useArchPT;
 139     // running KvmCPU in SE mode requires special initialization
 140     bool kvmInSE;
 141
 142     PageTableBase* pTable;
 143
 144   protected:
 145     /// Memory proxy for initialization (image loading)
 146     SETranslatingPortProxy initVirtMem;
 147
 148   private:
 149     static const int NUM_FDS = 1024;
 150
 151     // File descriptor remapping support.
 152     std::shared_ptr<std::array<FDEntry, NUM_FDS>> fd_array;
 153
 154     // Standard file descriptor options for initialization and checkpoints.
 155     std::map<std::string, int> imap;
 156     std::map<std::string, int> oemap;
 157
 158   public:
 159     // inherit file descriptor map from another process (necessary for clone)
 160     void inheritFDArray(Process *p);
 161
 162     // override of virtual SimObject method: register statistics
 163     void regStats() override;
 164
 165     // After getting registered with system object, tell process which
 166     // system-wide context id it is assigned.
 167     void assignThreadContext(ContextID context_id)
 168     {
 169         contextIds.push_back(context_id);
 170     }
 171
 172     // Find a free context to use
 173     ThreadContext *findFreeContext();
 174
 175     // provide program name for debug messages
 176     virtual const char *progName() const { return "<unknown>"; }
 177
 178     // generate new target fd for sim_fd
 179     int allocFD(int sim_fd, const std::string& filename, int flags, int mode,
 180                 bool pipe);
 181
 182     // disassociate target fd with simulator fd and cleanup subsidiary fields
 183     void resetFDEntry(int tgt_fd);
 184
 185     // look up simulator fd for given target fd
 186     int getSimFD(int tgt_fd);
 187
 188     // look up fd entry for a given target fd
 189     FDEntry *getFDEntry(int tgt_fd);
 190
 191     // look up target fd for given host fd
 192     // Assumes a 1:1 mapping between target file descriptor and host file
 193     // descriptor. Given the current API, this must be true given that it's
 194     // not possible to map multiple target file descriptors to the same host
 195     // file descriptor
 196     int getTgtFD(int sim_fd);
 197
 198     // fix all offsets for currently open files and save them
 199     void fixFileOffsets();
 200
 201     // find all offsets for currently open files and save them
 202     void findFileOffsets();
 203
 204     // set the source of this read pipe for a checkpoint resume
 205     void setReadPipeSource(int read_pipe_fd, int source_fd);
 206
 207     virtual void syscall(int64_t callnum, ThreadContext *tc) = 0;
 208
 209     void allocateMem(Addr vaddr, int64_t size, bool clobber = false);
 210
 211     /// Attempt to fix up a fault at vaddr by allocating a page on the stack.
 212     /// @return Whether the fault has been fixed.
 213     bool fixupStackFault(Addr vaddr);
 214
 215     /**
 216      * Maps a contiguous range of virtual addresses in this process's
 217      * address space to a contiguous range of physical addresses.
 218      * This function exists primarily to expose the map operation to
 219      * python, so that configuration scripts can set up mappings in SE mode.
 220      *
 221      * @param vaddr The starting virtual address of the range.
 222      * @param paddr The starting physical address of the range.
 223      * @param size The length of the range in bytes.
 224      * @param cacheable Specifies whether accesses are cacheable.
 225      * @return True if the map operation was successful.  (At this
 226      *           point in time, the map operation always succeeds.)
 227      */
 228     bool map(Addr vaddr, Addr paddr, int size, bool cacheable = true);
 229
 230     void serialize(CheckpointOut &cp) const override;
 231     void unserialize(CheckpointIn &cp) override;
 232 };
 233
 234 //
 235 // "Live" process with system calls redirected to host system
 236 //
 237 class ObjectFile;
 238 class LiveProcess : public Process
 239 {
 240   protected:
 241     ObjectFile *objFile;
 242     std::vector<std::string> argv;
 243     std::vector<std::string> envp;
 244     std::string cwd;
 245     std::string executable;
 246
 247     LiveProcess(LiveProcessParams *params, ObjectFile *objFile);
 248
 249     // Id of the owner of the process
 250     uint64_t __uid;
 251     uint64_t __euid;
 252     uint64_t __gid;
 253     uint64_t __egid;
 254
 255     // pid of the process and it's parent
 256     uint64_t __pid;
 257     uint64_t __ppid;
 258
 259     // Emulated drivers available to this process
 260     std::vector<EmulatedDriver *> drivers;
 261
 262   public:
 263
 264     enum AuxiliaryVectorType {
 265         M5_AT_NULL = 0,
 266         M5_AT_IGNORE = 1,
 267         M5_AT_EXECFD = 2,
 268         M5_AT_PHDR = 3,
 269         M5_AT_PHENT = 4,
 270         M5_AT_PHNUM = 5,
 271         M5_AT_PAGESZ = 6,
 272         M5_AT_BASE = 7,
 273         M5_AT_FLAGS = 8,
 274         M5_AT_ENTRY = 9,
 275         M5_AT_NOTELF = 10,
 276         M5_AT_UID = 11,
 277         M5_AT_EUID = 12,
 278         M5_AT_GID = 13,
 279         M5_AT_EGID = 14,
 280         // The following may be specific to Linux
 281         M5_AT_PLATFORM = 15,
 282         M5_AT_HWCAP = 16,
 283         M5_AT_CLKTCK = 17,
 284
 285         M5_AT_SECURE = 23,
 286         M5_BASE_PLATFORM = 24,
 287         M5_AT_RANDOM = 25,
 288
 289         M5_AT_EXECFN = 31,
 290
 291         M5_AT_VECTOR_SIZE = 44
 292     };
 293
 294     inline uint64_t uid() {return __uid;}
 295     inline uint64_t euid() {return __euid;}
 296     inline uint64_t gid() {return __gid;}
 297     inline uint64_t egid() {return __egid;}
 298     inline uint64_t pid() {return __pid;}
 299     inline uint64_t ppid() {return __ppid;}
 300
 301     // provide program name for debug messages
 302     virtual const char *progName() const { return executable.c_str(); }
 303
 304     std::string
 305     fullPath(const std::string &filename)
 306     {
 307         if (filename[0] == '/' || cwd.empty())
 308             return filename;
 309
 310         std::string full = cwd;
 311
 312         if (cwd[cwd.size() - 1] != '/')
 313             full += '/';
 314
 315         return full + filename;
 316     }
 317
 318     std::string getcwd() const { return cwd; }
 319
 320     virtual void syscall(int64_t callnum, ThreadContext *tc);
 321
 322     virtual TheISA::IntReg getSyscallArg(ThreadContext *tc, int &i) = 0;
 323     virtual TheISA::IntReg getSyscallArg(ThreadContext *tc, int &i, int width);
 324     virtual void setSyscallArg(ThreadContext *tc,
 325             int i, TheISA::IntReg val) = 0;
 326     virtual void setSyscallReturn(ThreadContext *tc,
 327             SyscallReturn return_value) = 0;
 328
 329     virtual SyscallDesc *getDesc(int callnum) = 0;
 330
 331     /**
 332      * Find an emulated device driver.
 333      *
 334      * @param filename Name of the device (under /dev)
 335      * @return Pointer to driver object if found, else NULL
 336      */
 337     EmulatedDriver *findDriver(std::string filename);
 338
 339     // this function is used to create the LiveProcess object, since
 340     // we can't tell which subclass of LiveProcess to use until we
 341     // open and look at the object file.
 342     static LiveProcess *create(LiveProcessParams *params);
 343 };
 344
 345
 346 #endif // __PROCESS_HH__