From e475dba424d70e99646f897fae832f87b1cf15cf Mon Sep 17 00:00:00 2001 From: Steve Reinhardt Date: Tue, 7 Oct 2003 23:13:01 -0700 Subject: New loader structure. Expand Nate's ObjectFile to automatically detect file formats and generate an appropriate child object, which knows how to load its text & data into memory (and symbols, for ecoff only at this point). Ecoff format supports Tru64 binaries, kernel, and console. A.out format is used by PAL code. Elf support is there and appears to work for Alpha/Linux binaries, but awaits a Linux syscall emulation layer before further testing. arch/alpha/ecoff_machdep.h: base/coff_sym.h: base/coff_symconst.h: base/exec_ecoff.h: Add Id string & provenance comment, clean up types base/object_file.cc: base/object_file.hh: Add auto format detection and text/data loading. sim/prog.cc: Moved binary loading & stack setup here (was in arch/alpha/loader.cc). Some of this is platform-dependent, but I think most of it is not. We'll factor out the platform-dependent parts when the need arises. sim/prog.hh: Get rid of unused environ_base field. sim/system.cc: Use new ObjectFile loader structure for console, kernel, & palcode. --HG-- extra : convert_revision : 8eae509bf71cf204bc3ec78c68699cfd01baed97 --- base/elf_object.cc | 140 +++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 140 insertions(+) create mode 100644 base/elf_object.cc (limited to 'base/elf_object.cc') diff --git a/base/elf_object.cc b/base/elf_object.cc new file mode 100644 index 000000000..97f50e289 --- /dev/null +++ b/base/elf_object.cc @@ -0,0 +1,140 @@ +/* + * Copyright (c) 2003 The Regents of The University of Michigan + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions are + * met: redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer; + * redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution; + * neither the name of the copyright holders nor the names of its + * contributors may be used to endorse or promote products derived from + * this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ + +#include + +#include "elf_object.hh" + +#include "functional_memory.hh" +#include "symtab.hh" + +#include "trace.hh" // for DPRINTF + +#include "exec_elf.h" + +using namespace std; + +ObjectFile * +ElfObject::tryFile(const string &fname, int fd, size_t len, uint8_t *data) +{ + if (memcmp(((Elf64_Ehdr *)data)->e_ident, ELFMAG, SELFMAG) == 0) { + // for now we'll assume it's a 64-bit Alpha binary + return new ElfObject(fname, fd, len, data); + } + else { + return NULL; + } +} + + +ElfObject::ElfObject(const string &_filename, int _fd, + size_t _len, uint8_t *_data) + : ObjectFile(_filename, _fd, _len, _data) +{ + ehdr = (Elf64_Ehdr *)fileData; + + entry = ehdr->e_entry; + + phdr = (Elf64_Phdr *)(fileData + ehdr->e_phoff); + assert(sizeof(Elf64_Phdr) == ehdr->e_phentsize); + + bool foundText = false; + bool foundData = false; + for (int i = 0; i < ehdr->e_phnum; ++i) { + Elf64_Phdr *p = &phdr[i]; + + // for now we don't care about non-loadable segments + if (!(p->p_type & PT_LOAD)) + continue; + + if (p->p_flags & PF_X) { + // executable: must be text + assert(!foundText); + foundText = true; + textPhdrIdx = i; + text.baseAddr = p->p_vaddr; + text.size = p->p_filesz; + assert(p->p_filesz == p->p_memsz); + } + else { + assert(p->p_flags & PF_R); + assert(!foundData); + foundData = true; + dataPhdrIdx = i; + data.baseAddr = p->p_vaddr; + data.size = p->p_filesz; + bss.baseAddr = data.baseAddr + data.size; + bss.size = p->p_memsz - p->p_filesz; + } + } + + assert(foundText && foundData); + + DPRINTFR(Loader, "text: 0x%x %d\ndata: 0x%x %d\nbss: 0x%x %d\n", + text.baseAddr, text.size, data.baseAddr, data.size, + bss.baseAddr, bss.size); +} + + +bool +ElfObject::loadSections(FunctionalMemory *mem, bool loadPhys) +{ + Addr textAddr = text.baseAddr; + Addr dataAddr = data.baseAddr; + + if (loadPhys) { + textAddr &= (ULL(1) << 40) - 1; + dataAddr &= (ULL(1) << 40) - 1; + } + + // Since we don't really have an MMU and all memory is + // zero-filled, there's no need to set up the BSS segment. + if (text.size != 0) + mem->prot_write(textAddr, fileData + phdr[textPhdrIdx].p_offset, + text.size); + if (data.size != 0) + mem->prot_write(dataAddr, fileData + phdr[dataPhdrIdx].p_offset, + data.size); + + return true; +} + + +bool +ElfObject::loadGlobalSymbols(SymbolTable *symtab) +{ + // symbols not supported yet + return false; +} + +bool +ElfObject::loadLocalSymbols(SymbolTable *symtab) +{ + // symbols not supported yet + return false; +} -- cgit v1.2.3