diff options
Diffstat (limited to 'gold/output.cc')
| -rw-r--r-- | gold/output.cc | 225 |
1 files changed, 198 insertions, 27 deletions
diff --git a/gold/output.cc b/gold/output.cc index 739e00e..5c1fae9 100644 --- a/gold/output.cc +++ b/gold/output.cc @@ -280,6 +280,7 @@ Output_segment_headers::Output_segment_headers( const Layout::Segment_list& segment_list) : segment_list_(segment_list) { + this->set_current_data_size_for_child(this->do_size()); } void @@ -1794,6 +1795,21 @@ Output_symtab_xindex::endian_do_write(unsigned char* const oview) // Output_section::Input_section methods. +// Return the current data size. For an input section we store the size here. +// For an Output_section_data, we have to ask it for the size. + +off_t +Output_section::Input_section::current_data_size() const +{ + if (this->is_input_section()) + return this->u1_.data_size; + else + { + this->u2_.posd->pre_finalize_data_size(); + return this->u2_.posd->current_data_size(); + } +} + // Return the data size. For an input section we store the size here. // For an Output_section_data, we have to ask it for the size. @@ -2003,9 +2019,11 @@ Output_section::Output_section(const char* name, elfcpp::Elf_Word type, section_offsets_need_adjustment_(false), is_noload_(false), always_keeps_input_sections_(false), + has_fixed_layout_(false), tls_offset_(0), checkpoint_(NULL), - lookup_maps_(new Output_section_lookup_maps) + lookup_maps_(new Output_section_lookup_maps), + free_list_() { // An unallocated section has no address. Forcing this means that // we don't need special treatment for symbols defined in debug @@ -2086,9 +2104,11 @@ Output_section::add_input_section(Layout* layout, // a Output_data_merge. We don't try to handle relocations for such // a section. We don't try to handle empty merge sections--they // mess up the mappings, and are useless anyhow. + // FIXME: Need to handle merge sections during incremental update. if ((sh_flags & elfcpp::SHF_MERGE) != 0 && reloc_shndx == 0 - && shdr.get_sh_size() > 0) + && shdr.get_sh_size() > 0 + && !parameters->incremental()) { // Keep information about merged input sections for rebuilding fast // lookup maps if we have sections-script or we do relaxation. @@ -2105,9 +2125,30 @@ Output_section::add_input_section(Layout* layout, } } - off_t offset_in_section = this->current_data_size_for_child(); - off_t aligned_offset_in_section = align_address(offset_in_section, - addralign); + section_size_type input_section_size = shdr.get_sh_size(); + section_size_type uncompressed_size; + if (object->section_is_compressed(shndx, &uncompressed_size)) + input_section_size = uncompressed_size; + + off_t offset_in_section; + off_t aligned_offset_in_section; + if (this->has_fixed_layout()) + { + // For incremental updates, find a chunk of unused space in the section. + offset_in_section = this->free_list_.allocate(input_section_size, + addralign, 0); + if (offset_in_section == -1) + gold_fatal(_("out of patch space; relink with --incremental-full")); + aligned_offset_in_section = offset_in_section; + } + else + { + offset_in_section = this->current_data_size_for_child(); + aligned_offset_in_section = align_address(offset_in_section, + addralign); + this->set_current_data_size_for_child(aligned_offset_in_section + + input_section_size); + } // Determine if we want to delay code-fill generation until the output // section is written. When the target is relaxing, we want to delay fill @@ -2144,14 +2185,6 @@ Output_section::add_input_section(Layout* layout, } } - section_size_type input_section_size = shdr.get_sh_size(); - section_size_type uncompressed_size; - if (object->section_is_compressed(shndx, &uncompressed_size)) - input_section_size = uncompressed_size; - - this->set_current_data_size_for_child(aligned_offset_in_section - + input_section_size); - // We need to keep track of this section if we are already keeping // track of sections, or if we are relaxing. Also, if this is a // section which requires sorting, or which may require sorting in @@ -2178,6 +2211,14 @@ Output_section::add_input_section(Layout* layout, this->set_input_section_order_specified(); } } + if (this->has_fixed_layout()) + { + // For incremental updates, finalize the address and offset now. + uint64_t addr = this->address(); + isecn.set_address_and_file_offset(addr + aligned_offset_in_section, + aligned_offset_in_section, + this->offset()); + } this->input_sections_.push_back(isecn); } @@ -2194,11 +2235,38 @@ Output_section::add_output_section_data(Output_section_data* posd) if (posd->is_data_size_valid()) { - off_t offset_in_section = this->current_data_size_for_child(); - off_t aligned_offset_in_section = align_address(offset_in_section, - posd->addralign()); - this->set_current_data_size_for_child(aligned_offset_in_section - + posd->data_size()); + off_t offset_in_section; + if (this->has_fixed_layout()) + { + // For incremental updates, find a chunk of unused space. + offset_in_section = this->free_list_.allocate(posd->data_size(), + posd->addralign(), 0); + if (offset_in_section == -1) + gold_fatal(_("out of patch space; relink with --incremental-full")); + // Finalize the address and offset now. + uint64_t addr = this->address(); + off_t offset = this->offset(); + posd->set_address_and_file_offset(addr + offset_in_section, + offset + offset_in_section); + } + else + { + offset_in_section = this->current_data_size_for_child(); + off_t aligned_offset_in_section = align_address(offset_in_section, + posd->addralign()); + this->set_current_data_size_for_child(aligned_offset_in_section + + posd->data_size()); + } + } + else if (this->has_fixed_layout()) + { + // For incremental updates, arrange for the data to have a fixed layout. + // This will mean that additions to the data must be allocated from + // free space within the containing output section. + uint64_t addr = this->address(); + posd->set_address(addr); + posd->set_file_offset(0); + // FIXME: Mark *POSD as part of a fixed-layout section. } } @@ -2713,6 +2781,30 @@ Output_section::find_starting_output_address(const Relobj* object, return false; } +// Update the data size of an Output_section. + +void +Output_section::update_data_size() +{ + if (this->input_sections_.empty()) + return; + + if (this->must_sort_attached_input_sections() + || this->input_section_order_specified()) + this->sort_attached_input_sections(); + + off_t off = this->first_input_offset_; + for (Input_section_list::iterator p = this->input_sections_.begin(); + p != this->input_sections_.end(); + ++p) + { + off = align_address(off, p->addralign()); + off += p->current_data_size(); + } + + this->set_current_data_size_for_child(off); +} + // Set the data size of an Output_section. This is where we handle // setting the addresses of any Output_section_data objects. @@ -3483,6 +3575,30 @@ Output_section::print_merge_stats() p->print_merge_stats(this->name_); } +// Set a fixed layout for the section. Used for incremental update links. + +void +Output_section::set_fixed_layout(uint64_t sh_addr, off_t sh_offset, + off_t sh_size, uint64_t sh_addralign) +{ + this->addralign_ = sh_addralign; + this->set_current_data_size(sh_size); + if ((this->flags_ & elfcpp::SHF_ALLOC) != 0) + this->set_address(sh_addr); + this->set_file_offset(sh_offset); + this->finalize_data_size(); + this->free_list_.init(sh_size, false); + this->has_fixed_layout_ = true; +} + +// Reserve space within the fixed layout for the section. Used for +// incremental update links. +void +Output_section::reserve(uint64_t sh_offset, uint64_t sh_size) +{ + this->free_list_.remove(sh_offset, sh_offset + sh_size); +} + // Output segment methods. Output_segment::Output_segment(elfcpp::Elf_Word type, elfcpp::Elf_Word flags) @@ -3692,7 +3808,7 @@ Output_segment::has_dynamic_reloc_list(const Output_data_list* pdl) const // and *PSHNDX. uint64_t -Output_segment::set_section_addresses(const Layout* layout, bool reset, +Output_segment::set_section_addresses(Layout* layout, bool reset, uint64_t addr, unsigned int* increase_relro, bool* has_relro, @@ -3839,13 +3955,16 @@ Output_segment::set_section_addresses(const Layout* layout, bool reset, // structures. uint64_t -Output_segment::set_section_list_addresses(const Layout* layout, bool reset, +Output_segment::set_section_list_addresses(Layout* layout, bool reset, Output_data_list* pdl, uint64_t addr, off_t* poff, unsigned int* pshndx, bool* in_tls) { off_t startoff = *poff; + // For incremental updates, we may allocate non-fixed sections from + // free space in the file. This keeps track of the high-water mark. + off_t maxoff = startoff; off_t off = startoff; for (Output_data_list::iterator p = pdl->begin(); @@ -3855,8 +3974,8 @@ Output_segment::set_section_list_addresses(const Layout* layout, bool reset, if (reset) (*p)->reset_address_and_file_offset(); - // When using a linker script the section will most likely - // already have an address. + // When doing an incremental update or when using a linker script, + // the section will most likely already have an address. if (!(*p)->is_address_valid()) { uint64_t align = (*p)->addralign(); @@ -3894,9 +4013,43 @@ Output_segment::set_section_list_addresses(const Layout* layout, bool reset, } } - off = align_address(off, align); - (*p)->set_address_and_file_offset(addr + (off - startoff), off); + // FIXME: Need to handle TLS and .bss with incremental update. + if (!parameters->incremental_update() + || (*p)->is_section_flag_set(elfcpp::SHF_TLS) + || (*p)->is_section_type(elfcpp::SHT_NOBITS)) + { + off = align_address(off, align); + (*p)->set_address_and_file_offset(addr + (off - startoff), off); + } + else + { + // Incremental update: allocate file space from free list. + (*p)->pre_finalize_data_size(); + off_t current_size = (*p)->current_data_size(); + off = layout->allocate(current_size, align, startoff); + if (off == -1) + { + gold_assert((*p)->output_section() != NULL); + gold_fatal(_("out of patch space for section %s; " + "relink with --incremental-full"), + (*p)->output_section()->name()); + } + (*p)->set_address_and_file_offset(addr + (off - startoff), off); + if ((*p)->data_size() > current_size) + { + gold_assert((*p)->output_section() != NULL); + gold_fatal(_("%s: section changed size; " + "relink with --incremental-full"), + (*p)->output_section()->name()); + } + } } + else if (parameters->incremental_update()) + { + // For incremental updates, use the fixed offset for the + // high-water mark computation. + off = (*p)->offset(); + } else { // The script may have inserted a skip forward, but it @@ -3930,6 +4083,13 @@ Output_segment::set_section_list_addresses(const Layout* layout, bool reset, (*p)->finalize_data_size(); } + gold_debug(DEBUG_INCREMENTAL, + "set_section_list_addresses: %08lx %08lx %s", + static_cast<long>(off), + static_cast<long>((*p)->data_size()), + ((*p)->output_section() != NULL + ? (*p)->output_section()->name() : "(special)")); + // We want to ignore the size of a SHF_TLS or SHT_NOBITS // section. Such a section does not affect the size of a // PT_LOAD segment. @@ -3937,6 +4097,9 @@ Output_segment::set_section_list_addresses(const Layout* layout, bool reset, || !(*p)->is_section_type(elfcpp::SHT_NOBITS)) off += (*p)->data_size(); + if (off > maxoff) + maxoff = off; + if ((*p)->is_section()) { (*p)->set_out_shndx(*pshndx); @@ -3944,8 +4107,8 @@ Output_segment::set_section_list_addresses(const Layout* layout, bool reset, } } - *poff = off; - return addr + (off - startoff); + *poff = maxoff; + return addr + (maxoff - startoff); } // For a non-PT_LOAD segment, set the offset from the sections, if @@ -4029,7 +4192,15 @@ Output_segment::set_offset(unsigned int increase) { uint64_t page_align = parameters->target().common_pagesize(); uint64_t segment_end = this->vaddr_ + this->memsz_; - gold_assert(segment_end == align_address(segment_end, page_align)); + if (parameters->incremental_update()) + { + // The INCREASE_RELRO calculation is bypassed for an incremental + // update, so we need to adjust the segment size manually here. + segment_end = align_address(segment_end, page_align); + this->memsz_ = segment_end - this->vaddr_; + } + else + gold_assert(segment_end == align_address(segment_end, page_align)); } // If this is a TLS segment, align the memory size. The code in |