mirror of
https://github.com/LadybirdBrowser/ladybird.git
synced 2024-11-25 17:10:23 +00:00
746 lines
23 KiB
C++
746 lines
23 KiB
C++
#include "Ext2FileSystem.h"
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#include "ext2_fs.h"
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#include <AK/Bitmap.h>
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#include <AK/StdLib.h>
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#include <cstdio>
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#include <cstring>
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#include "kmalloc.h"
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//#define EXT2_DEBUG
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RetainPtr<Ext2FileSystem> Ext2FileSystem::create(RetainPtr<BlockDevice> device)
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{
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return adopt(*new Ext2FileSystem(std::move(device)));
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}
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Ext2FileSystem::Ext2FileSystem(RetainPtr<BlockDevice> device)
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: DeviceBackedFileSystem(std::move(device))
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{
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}
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Ext2FileSystem::~Ext2FileSystem()
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{
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}
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ByteBuffer Ext2FileSystem::readSuperBlock() const
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{
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auto buffer = ByteBuffer::createUninitialized(1024);
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device().readBlock(2, buffer.pointer());
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device().readBlock(3, buffer.offsetPointer(512));
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return buffer;
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}
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bool Ext2FileSystem::writeSuperBlock(const ext2_super_block& sb)
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{
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const byte* raw = (const byte*)&sb;
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bool success;
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success = device().writeBlock(2, raw);
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ASSERT(success);
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success = device().writeBlock(3, raw + 512);
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ASSERT(success);
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// FIXME: This is an ugly way to refresh the superblock cache. :-|
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superBlock();
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return true;
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}
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unsigned Ext2FileSystem::firstBlockOfGroup(unsigned groupIndex) const
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{
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return superBlock().s_first_data_block + (groupIndex * superBlock().s_blocks_per_group);
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}
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const ext2_super_block& Ext2FileSystem::superBlock() const
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{
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if (!m_cachedSuperBlock)
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m_cachedSuperBlock = readSuperBlock();
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return *reinterpret_cast<ext2_super_block*>(m_cachedSuperBlock.pointer());
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}
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const ext2_group_desc& Ext2FileSystem::blockGroupDescriptor(unsigned groupIndex) const
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{
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// FIXME: Should this fail gracefully somehow?
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ASSERT(groupIndex <= m_blockGroupCount);
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if (!m_cachedBlockGroupDescriptorTable) {
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unsigned blocksToRead = ceilDiv(m_blockGroupCount * sizeof(ext2_group_desc), blockSize());
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printf("[ext2fs] block group count: %u, blocks-to-read: %u\n", m_blockGroupCount, blocksToRead);
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unsigned firstBlockOfBGDT = blockSize() == 1024 ? 2 : 1;
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printf("[ext2fs] first block of BGDT: %u\n", firstBlockOfBGDT);
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m_cachedBlockGroupDescriptorTable = readBlocks(firstBlockOfBGDT, blocksToRead);
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}
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return reinterpret_cast<ext2_group_desc*>(m_cachedBlockGroupDescriptorTable.pointer())[groupIndex - 1];
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}
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bool Ext2FileSystem::initialize()
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{
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auto& superBlock = this->superBlock();
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printf("[ext2fs] super block magic: %04x (super block size: %u)\n", superBlock.s_magic, sizeof(ext2_super_block));
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if (superBlock.s_magic != EXT2_SUPER_MAGIC)
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return false;
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printf("[ext2fs] %u inodes, %u blocks\n", superBlock.s_inodes_count, superBlock.s_blocks_count);
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printf("[ext2fs] block size = %u\n", EXT2_BLOCK_SIZE(&superBlock));
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printf("[ext2fs] first data block = %u\n", superBlock.s_first_data_block);
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printf("[ext2fs] inodes per block = %u\n", inodesPerBlock());
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printf("[ext2fs] inodes per group = %u\n", inodesPerGroup());
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printf("[ext2fs] free inodes = %u\n", superBlock.s_free_inodes_count);
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printf("[ext2fs] desc per block = %u\n", EXT2_DESC_PER_BLOCK(&superBlock));
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printf("[ext2fs] desc size = %u\n", EXT2_DESC_SIZE(&superBlock));
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setBlockSize(EXT2_BLOCK_SIZE(&superBlock));
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m_blockGroupCount = ceilDiv(superBlock.s_blocks_count, superBlock.s_blocks_per_group);
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if (m_blockGroupCount == 0) {
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printf("[ext2fs] no block groups :(\n");
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return false;
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}
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for (unsigned i = 1; i <= m_blockGroupCount; ++i) {
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auto& group = blockGroupDescriptor(i);
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printf("[ext2fs] group[%u] { block_bitmap: %u, inode_bitmap: %u, inode_table: %u }\n",
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i,
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group.bg_block_bitmap,
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group.bg_inode_bitmap,
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group.bg_inode_table);
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}
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return true;
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}
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const char* Ext2FileSystem::className() const
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{
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return "ext2fs";
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}
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InodeIdentifier Ext2FileSystem::rootInode() const
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{
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return { id(), EXT2_ROOT_INO };
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}
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#ifdef EXT2_DEBUG
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static void dumpExt2Inode(const ext2_inode& inode)
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{
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printf("Dump of ext2_inode:\n");
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printf(" i_size: %u\n", inode.i_size);
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printf(" i_mode: %u\n", inode.i_mode);
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printf(" i_blocks: %u\n", inode.i_blocks);
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printf(" i_uid: %u\n", inode.i_uid);
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printf(" i_gid: %u\n", inode.i_gid);
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}
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#endif
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ByteBuffer Ext2FileSystem::readBlockContainingInode(unsigned inode, unsigned& blockIndex, unsigned& offset) const
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{
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auto& superBlock = this->superBlock();
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if (inode != EXT2_ROOT_INO && inode < EXT2_FIRST_INO(&superBlock))
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return { };
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if (inode > superBlock.s_inodes_count)
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return { };
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auto& bgd = blockGroupDescriptor(groupIndexFromInode(inode));
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offset = ((inode - 1) % inodesPerGroup()) * inodeSize();
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blockIndex = bgd.bg_inode_table + (offset >> EXT2_BLOCK_SIZE_BITS(&superBlock));
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offset &= blockSize() - 1;
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return readBlock(blockIndex);
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}
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OwnPtr<ext2_inode> Ext2FileSystem::lookupExt2Inode(unsigned inode) const
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{
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unsigned blockIndex;
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unsigned offset;
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auto block = readBlockContainingInode(inode, blockIndex, offset);
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if (!block)
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return nullptr;
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auto* e2inode = reinterpret_cast<ext2_inode*>(kmalloc(inodeSize()));
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memcpy(e2inode, reinterpret_cast<ext2_inode*>(block.offsetPointer(offset)), inodeSize());
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#ifdef EXT2_DEBUG
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dumpExt2Inode(*e2inode);
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#endif
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return OwnPtr<ext2_inode>(e2inode);
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}
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InodeMetadata Ext2FileSystem::inodeMetadata(InodeIdentifier inode) const
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{
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ASSERT(inode.fileSystemID() == id());
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auto e2inode = lookupExt2Inode(inode.index());
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if (!e2inode)
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return InodeMetadata();
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InodeMetadata metadata;
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metadata.inode = inode;
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metadata.size = e2inode->i_size;
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metadata.mode = e2inode->i_mode;
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metadata.uid = e2inode->i_uid;
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metadata.gid = e2inode->i_gid;
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metadata.linkCount = e2inode->i_links_count;
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metadata.atime = e2inode->i_atime;
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metadata.ctime = e2inode->i_ctime;
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metadata.mtime = e2inode->i_mtime;
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metadata.dtime = e2inode->i_dtime;
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return metadata;
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}
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Vector<unsigned> Ext2FileSystem::blockListForInode(const ext2_inode& e2inode) const
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{
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unsigned entriesPerBlock = EXT2_ADDR_PER_BLOCK(&superBlock());
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// NOTE: i_blocks is number of 512-byte blocks, not number of fs-blocks.
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unsigned blockCount = e2inode.i_blocks / (blockSize() / 512);
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unsigned blocksRemaining = blockCount;
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Vector<unsigned> list;
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list.ensureCapacity(blocksRemaining);
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unsigned directCount = min(blockCount, (unsigned)EXT2_NDIR_BLOCKS);
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for (unsigned i = 0; i < directCount; ++i) {
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list.append(e2inode.i_block[i]);
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--blocksRemaining;
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}
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if (!blocksRemaining)
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return list;
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auto processBlockArray = [&] (unsigned arrayBlockIndex, std::function<void(unsigned)> callback) {
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auto arrayBlock = readBlock(arrayBlockIndex);
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ASSERT(arrayBlock);
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auto* array = reinterpret_cast<const __u32*>(arrayBlock.pointer());
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unsigned count = min(blocksRemaining, entriesPerBlock);
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for (unsigned i = 0; i < count; ++i) {
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if (!array[i]) {
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blocksRemaining = 0;
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return;
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}
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callback(array[i]);
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--blocksRemaining;
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}
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};
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processBlockArray(e2inode.i_block[EXT2_IND_BLOCK], [&] (unsigned entry) {
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list.append(entry);
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});
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if (!blocksRemaining)
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return list;
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processBlockArray(e2inode.i_block[EXT2_DIND_BLOCK], [&] (unsigned entry) {
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processBlockArray(entry, [&] (unsigned entry) {
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list.append(entry);
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});
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});
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if (!blocksRemaining)
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return list;
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processBlockArray(e2inode.i_block[EXT2_TIND_BLOCK], [&] (unsigned entry) {
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processBlockArray(entry, [&] (unsigned entry) {
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processBlockArray(entry, [&] (unsigned entry) {
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list.append(entry);
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});
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});
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});
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return list;
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}
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ByteBuffer Ext2FileSystem::readInode(InodeIdentifier inode) const
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{
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ASSERT(inode.fileSystemID() == id());
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auto e2inode = lookupExt2Inode(inode.index());
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if (!e2inode) {
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printf("[ext2fs] readInode: metadata lookup for inode %u failed\n", inode.index());
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return nullptr;
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}
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// Symbolic links shorter than 60 characters are store inline inside the i_block array.
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// This avoids wasting an entire block on short links. (Most links are short.)
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static const unsigned maxInlineSymlinkLength = 60;
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if (isSymbolicLink(e2inode->i_mode) && e2inode->i_size < maxInlineSymlinkLength) {
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auto inlineSymlink = ByteBuffer::createUninitialized(e2inode->i_size);
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memcpy(inlineSymlink.pointer(), e2inode->i_block, e2inode->i_size);
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return inlineSymlink;
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}
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auto list = blockListForInode(*e2inode);
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if (list.isEmpty()) {
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printf("[ext2fs] readInode: empty block list for inode %u\n", inode.index());
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return nullptr;
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}
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auto contents = ByteBuffer::createUninitialized(list.size() * blockSize());
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auto* out = contents.pointer();
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for (unsigned i = 0; i < list.size(); ++i) {
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auto block = readBlock(list[i]);
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if (!block) {
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printf("[ext2fs] readInode: readBlock(%u) failed\n", list[i]);
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return nullptr;
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}
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memcpy(out, block.pointer(), block.size());
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out += blockSize();
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}
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#ifdef EXT2_DEBUG
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printf("trim from %u to %u\n", contents.size(), e2inode->i_size);
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#endif
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contents.trim(e2inode->i_size);
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return contents;
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}
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bool Ext2FileSystem::writeInode(InodeIdentifier inode, const ByteBuffer& data)
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{
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ASSERT(inode.fileSystemID() == id());
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auto e2inode = lookupExt2Inode(inode.index());
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if (!e2inode) {
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printf("[ext2fs] writeInode: metadata lookup for inode %u failed\n", inode.index());
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return false;
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}
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// FIXME: Support writing to symlink inodes.
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ASSERT(!isSymbolicLink(e2inode->i_mode));
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unsigned blocksNeededBefore = ceilDiv(e2inode->i_size, blockSize());
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unsigned blocksNeededAfter = ceilDiv(data.size(), blockSize());
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// FIXME: Support growing or shrinking the block list.
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ASSERT(blocksNeededBefore == blocksNeededAfter);
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auto list = blockListForInode(*e2inode);
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if (list.isEmpty()) {
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printf("[ext2fs] writeInode: empty block list for inode %u\n", inode.index());
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return false;
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}
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for (unsigned i = 0; i < list.size(); ++i) {
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auto section = data.slice(i * blockSize(), blockSize());
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printf("section = %p (%u)\n", section.pointer(), section.size());
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bool success = writeBlock(list[i], section);
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ASSERT(success);
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}
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return true;
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}
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bool Ext2FileSystem::enumerateDirectoryInode(InodeIdentifier inode, std::function<bool(const DirectoryEntry&)> callback) const
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{
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ASSERT(inode.fileSystemID() == id());
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ASSERT(isDirectoryInode(inode.index()));
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#ifdef EXT2_DEBUG
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printf("[ext2fs] Enumerating directory contents of inode %u:\n", inode.index());
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#endif
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auto buffer = readInode(inode);
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ASSERT(buffer);
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auto* entry = reinterpret_cast<ext2_dir_entry_2*>(buffer.pointer());
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char namebuf[EXT2_NAME_LEN + 1];
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while (entry < buffer.endPointer()) {
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if (entry->inode != 0) {
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memcpy(namebuf, entry->name, entry->name_len);
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namebuf[entry->name_len] = 0;
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#ifdef EXT2_DEBUG
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printf("inode: %u, name_len: %u, rec_len: %u, name: %s\n", entry->inode, entry->name_len, entry->rec_len, namebuf);
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#endif
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if (!callback({ namebuf, { id(), entry->inode }, entry->file_type }))
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break;
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}
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entry = (ext2_dir_entry_2*)((char*)entry + entry->rec_len);
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}
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return true;
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}
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bool Ext2FileSystem::addInodeToDirectory(unsigned directoryInode, unsigned inode, const String& name)
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{
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auto e2inodeForDirectory = lookupExt2Inode(directoryInode);
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ASSERT(e2inodeForDirectory);
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ASSERT(isDirectory(e2inodeForDirectory->i_mode));
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//#ifdef EXT2_DEBUG
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printf("[ext2fs] Adding inode %u with name '%s' to directory %u\n", inode, name.characters(), directoryInode);
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//#endif
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Vector<DirectoryEntry> entries;
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bool nameAlreadyExists = false;
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enumerateDirectoryInode({ id(), directoryInode }, [&] (const DirectoryEntry& entry) {
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if (entry.name == name) {
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nameAlreadyExists = true;
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return false;
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}
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entries.append(entry);
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return true;
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});
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if (nameAlreadyExists) {
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printf("[ext2fs] Name '%s' already exists in directory inode %u\n", name.characters(), directoryInode);
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return false;
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}
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entries.append({ name, { id(), inode } });
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return writeDirectoryInode(directoryInode, std::move(entries));
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}
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class BufferStream {
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public:
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explicit BufferStream(ByteBuffer& buffer)
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: m_buffer(buffer)
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{
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}
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void operator<<(byte value)
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{
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m_buffer[m_offset++] = value & 0xffu;
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}
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void operator<<(word value)
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{
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m_buffer[m_offset++] = value & 0xffu;
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m_buffer[m_offset++] = (byte)(value >> 8) & 0xffu;
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}
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void operator<<(dword value)
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{
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m_buffer[m_offset++] = value & 0xffu;
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m_buffer[m_offset++] = (byte)(value >> 8) & 0xffu;
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m_buffer[m_offset++] = (byte)(value >> 16) & 0xffu;
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m_buffer[m_offset++] = (byte)(value >> 24) & 0xffu;
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}
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void operator<<(const String& value)
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{
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for (unsigned i = 0; i < value.length(); ++i)
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m_buffer[m_offset++] = value[i];
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}
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void fillToEnd(byte ch)
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{
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while (m_offset < m_buffer.size())
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m_buffer[m_offset++] = ch;
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}
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private:
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ByteBuffer& m_buffer;
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size_t m_offset { 0 };
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};
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bool Ext2FileSystem::writeDirectoryInode(unsigned directoryInode, Vector<DirectoryEntry>&& entries)
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{
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printf("[ext2fs] New directory inode %u contents to write:\n", directoryInode);
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unsigned directorySize = 0;
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for (auto& entry : entries) {
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printf(" - %08u %s\n", entry.inode.index(), entry.name.characters());
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directorySize += EXT2_DIR_REC_LEN(entry.name.length());
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}
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unsigned blocksNeeded = ceilDiv(directorySize, blockSize());
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unsigned occupiedSize = blocksNeeded * blockSize();
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printf("[ext2fs] directory size: %u (occupied: %u)\n", directorySize, occupiedSize);
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auto directoryData = ByteBuffer::createUninitialized(occupiedSize);
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BufferStream stream(directoryData);
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for (unsigned i = 0; i < entries.size(); ++i) {
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auto& entry = entries[i];
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unsigned recordLength = EXT2_DIR_REC_LEN(entry.name.length());
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if (i == entries.size() - 1)
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recordLength += occupiedSize - directorySize;
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printf("* inode: %u", entry.inode.index());
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printf(", name_len: %u", word(entry.name.length()));
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printf(", rec_len: %u", word(recordLength));
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printf(", name: %s\n", entry.name.characters());
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stream << dword(entry.inode.index());
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stream << word(recordLength);
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stream << byte(entry.name.length());
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stream << byte(entry.fileType);
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stream << entry.name;
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unsigned padding = recordLength - entry.name.length() - 8;
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printf(" *** pad %u bytes\n", padding);
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for (unsigned j = 0; j < padding; ++j) {
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stream << byte(0);
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}
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}
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stream.fillToEnd(0);
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#if 0
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printf("data to write (%u):\n", directoryData.size());
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for (unsigned i = 0; i < directoryData.size(); ++i) {
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printf("%02x ", directoryData[i]);
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if ((i + 1) % 8 == 0)
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printf(" ");
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if ((i + 1) % 16 == 0)
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printf("\n");
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}
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printf("\n");
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#endif
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writeInode({ id(), directoryInode }, directoryData);
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return true;
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}
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unsigned Ext2FileSystem::inodesPerBlock() const
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{
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return EXT2_INODES_PER_BLOCK(&superBlock());
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}
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unsigned Ext2FileSystem::inodesPerGroup() const
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{
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|
return EXT2_INODES_PER_GROUP(&superBlock());
|
|
}
|
|
|
|
unsigned Ext2FileSystem::inodeSize() const
|
|
{
|
|
return EXT2_INODE_SIZE(&superBlock());
|
|
|
|
}
|
|
unsigned Ext2FileSystem::blocksPerGroup() const
|
|
{
|
|
return EXT2_BLOCKS_PER_GROUP(&superBlock());
|
|
}
|
|
|
|
void Ext2FileSystem::dumpBlockBitmap(unsigned groupIndex) const
|
|
{
|
|
ASSERT(groupIndex <= m_blockGroupCount);
|
|
auto& bgd = blockGroupDescriptor(groupIndex);
|
|
|
|
unsigned blocksInGroup = min(blocksPerGroup(), superBlock().s_blocks_count);
|
|
unsigned blockCount = ceilDiv(blocksInGroup, 8u);
|
|
|
|
auto bitmapBlocks = readBlocks(bgd.bg_block_bitmap, blockCount);
|
|
ASSERT(bitmapBlocks);
|
|
|
|
printf("[ext2fs] group[%u] block bitmap (bitmap occupies %u blocks):\n", groupIndex, blockCount);
|
|
|
|
auto bitmap = Bitmap::wrap(bitmapBlocks.pointer(), blocksInGroup);
|
|
for (unsigned i = 0; i < blocksInGroup; ++i) {
|
|
printf("%c", bitmap.get(i) ? '1' : '0');
|
|
}
|
|
printf("\n");
|
|
}
|
|
|
|
void Ext2FileSystem::dumpInodeBitmap(unsigned groupIndex) const
|
|
{
|
|
traverseInodeBitmap(groupIndex, [] (unsigned, const Bitmap& bitmap) {
|
|
for (unsigned i = 0; i < bitmap.size(); ++i)
|
|
printf("%c", bitmap.get(i) ? '1' : '0');
|
|
return true;
|
|
});
|
|
}
|
|
|
|
template<typename F>
|
|
void Ext2FileSystem::traverseInodeBitmap(unsigned groupIndex, F callback) const
|
|
{
|
|
ASSERT(groupIndex <= m_blockGroupCount);
|
|
auto& bgd = blockGroupDescriptor(groupIndex);
|
|
|
|
unsigned inodesInGroup = min(inodesPerGroup(), superBlock().s_inodes_count);
|
|
unsigned blockCount = ceilDiv(inodesInGroup, 8u);
|
|
|
|
for (unsigned i = 0; i < blockCount; ++i) {
|
|
auto block = readBlock(bgd.bg_inode_bitmap + i);
|
|
ASSERT(block);
|
|
bool shouldContinue = callback(i * (blockSize() / 8), Bitmap::wrap(block.pointer(), inodesInGroup));
|
|
if (!shouldContinue)
|
|
break;
|
|
}
|
|
}
|
|
|
|
bool Ext2FileSystem::setModificationTime(InodeIdentifier inode, dword timestamp)
|
|
{
|
|
ASSERT(inode.fileSystemID() == id());
|
|
|
|
auto e2inode = lookupExt2Inode(inode.index());
|
|
if (!e2inode)
|
|
return false;
|
|
|
|
printf("changing inode %u mtime from %u to %u\n", inode.index(), e2inode->i_mtime, timestamp);
|
|
e2inode->i_mtime = timestamp;
|
|
|
|
return writeExt2Inode(inode.index(), *e2inode);
|
|
}
|
|
|
|
bool Ext2FileSystem::writeExt2Inode(unsigned inode, const ext2_inode& e2inode)
|
|
{
|
|
unsigned blockIndex;
|
|
unsigned offset;
|
|
auto block = readBlockContainingInode(inode, blockIndex, offset);
|
|
if (!block)
|
|
return false;
|
|
memcpy(reinterpret_cast<ext2_inode*>(block.offsetPointer(offset)), &e2inode, inodeSize());
|
|
writeBlock(blockIndex, block);
|
|
return true;
|
|
}
|
|
|
|
bool Ext2FileSystem::isDirectoryInode(unsigned inode) const
|
|
{
|
|
if (auto e2inode = lookupExt2Inode(inode))
|
|
return isDirectory(e2inode->i_mode);
|
|
return false;
|
|
}
|
|
|
|
unsigned Ext2FileSystem::allocateInode(unsigned preferredGroup, unsigned expectedSize)
|
|
{
|
|
printf("[ext2fs] allocateInode(preferredGroup: %u, expectedSize: %u)\n", preferredGroup, expectedSize);
|
|
|
|
unsigned neededBlocks = ceilDiv(expectedSize, blockSize());
|
|
|
|
printf("[ext2fs] minimum needed blocks: %u\n", neededBlocks);
|
|
|
|
unsigned groupIndex = 0;
|
|
|
|
auto isSuitableGroup = [this, neededBlocks] (unsigned groupIndex) {
|
|
auto& bgd = blockGroupDescriptor(groupIndex);
|
|
return bgd.bg_free_inodes_count && bgd.bg_free_blocks_count >= neededBlocks;
|
|
};
|
|
|
|
if (preferredGroup && isSuitableGroup(preferredGroup)) {
|
|
groupIndex = preferredGroup;
|
|
} else {
|
|
for (unsigned i = 1; i <= m_blockGroupCount; ++i) {
|
|
if (isSuitableGroup(i))
|
|
groupIndex = i;
|
|
}
|
|
}
|
|
|
|
if (!groupIndex) {
|
|
printf("[ext2fs] allocateInode: no suitable group found for new inode with %u blocks needed :(\n", neededBlocks);
|
|
return 0;
|
|
}
|
|
|
|
printf("[ext2fs] allocateInode: found suitable group [%u] for new inode with %u blocks needed :^)\n", groupIndex, neededBlocks);
|
|
|
|
unsigned firstFreeInodeInGroup = 0;
|
|
traverseInodeBitmap(groupIndex, [&firstFreeInodeInGroup] (unsigned firstInodeInBitmap, const Bitmap& bitmap) {
|
|
for (unsigned i = 0; i < bitmap.size(); ++i) {
|
|
if (!bitmap.get(i)) {
|
|
firstFreeInodeInGroup = firstInodeInBitmap + i;
|
|
return false;
|
|
}
|
|
}
|
|
return true;
|
|
});
|
|
|
|
if (!firstFreeInodeInGroup) {
|
|
printf("[ext2fs] firstFreeInodeInGroup returned no inode, despite bgd claiming there are inodes :(\n");
|
|
return 0;
|
|
}
|
|
|
|
unsigned inode = firstFreeInodeInGroup;
|
|
printf("[ext2fs] found suitable inode %u\n", inode);
|
|
|
|
// FIXME: allocate blocks if needed!
|
|
|
|
return inode;
|
|
}
|
|
|
|
unsigned Ext2FileSystem::groupIndexFromInode(unsigned inode) const
|
|
{
|
|
if (!inode)
|
|
return 0;
|
|
return (inode - 1) / inodesPerGroup() + 1;
|
|
}
|
|
|
|
bool Ext2FileSystem::setInodeAllocationState(unsigned inode, bool newState)
|
|
{
|
|
auto& bgd = blockGroupDescriptor(groupIndexFromInode(inode));
|
|
|
|
// Update inode bitmap
|
|
unsigned inodesPerBitmapBlock = blockSize() * 8;
|
|
unsigned bitmapBlockIndex = (inode - 1) / inodesPerBitmapBlock;
|
|
unsigned bitIndex = (inode - 1) % inodesPerBitmapBlock;
|
|
auto block = readBlock(bgd.bg_inode_bitmap + bitmapBlockIndex);
|
|
ASSERT(block);
|
|
auto bitmap = Bitmap::wrap(block.pointer(), block.size());
|
|
bool currentState = bitmap.get(bitIndex);
|
|
printf("[ext2fs] setInodeAllocationState(%u) %u -> %u\n", inode, currentState, newState);
|
|
|
|
if (currentState == newState)
|
|
return true;
|
|
|
|
bitmap.set(bitIndex, newState);
|
|
writeBlock(bgd.bg_inode_bitmap + bitmapBlockIndex, block);
|
|
|
|
// Update superblock
|
|
auto& sb = *reinterpret_cast<ext2_super_block*>(m_cachedSuperBlock.pointer());
|
|
printf("[ext2fs] superblock free inode count %u -> %u\n", sb.s_free_inodes_count, sb.s_free_inodes_count - 1);
|
|
if (newState)
|
|
--sb.s_free_inodes_count;
|
|
else
|
|
++sb.s_free_inodes_count;
|
|
writeSuperBlock(sb);
|
|
|
|
// Update BGD
|
|
auto& mutableBGD = const_cast<ext2_group_desc&>(bgd);
|
|
if (newState)
|
|
--mutableBGD.bg_free_inodes_count;
|
|
else
|
|
++mutableBGD.bg_free_inodes_count;
|
|
printf("[ext2fs] group free inode count %u -> %u\n", bgd.bg_free_inodes_count, bgd.bg_free_inodes_count - 1);
|
|
|
|
unsigned blocksToWrite = ceilDiv(m_blockGroupCount * sizeof(ext2_group_desc), blockSize());
|
|
unsigned firstBlockOfBGDT = blockSize() == 1024 ? 2 : 1;
|
|
writeBlocks(firstBlockOfBGDT, blocksToWrite, m_cachedBlockGroupDescriptorTable);
|
|
|
|
return true;
|
|
}
|
|
|
|
InodeIdentifier Ext2FileSystem::createInode(InodeIdentifier parentInode, const String& name, word mode)
|
|
{
|
|
ASSERT(parentInode.fileSystemID() == id());
|
|
ASSERT(isDirectoryInode(parentInode.index()));
|
|
|
|
//#ifdef EXT2_DEBUG
|
|
printf("[ext2fs] Adding inode '%s' (mode %o) to parent directory %u:\n", name.characters(), mode, parentInode.index());
|
|
//#endif
|
|
|
|
// NOTE: This doesn't commit the inode allocation just yet!
|
|
auto inode = allocateInode(0, 0);
|
|
|
|
// Try adding it to the directory first, in case the name is already in use.
|
|
bool success = addInodeToDirectory(parentInode.index(), inode, name);
|
|
if (!success) {
|
|
printf("[ext2fs] failed to add inode to directory :(\n");
|
|
return { };
|
|
}
|
|
|
|
// Looks like we're good, time to update the inode bitmap and group+global inode counters.
|
|
success = setInodeAllocationState(inode, true);
|
|
ASSERT(success);
|
|
|
|
auto timestamp = time(nullptr);
|
|
auto e2inode = make<ext2_inode>();
|
|
memset(e2inode.ptr(), 0, sizeof(ext2_inode));
|
|
e2inode->i_mode = mode;
|
|
e2inode->i_uid = 0;
|
|
e2inode->i_size = 0;
|
|
e2inode->i_atime = timestamp;
|
|
e2inode->i_ctime = timestamp;
|
|
e2inode->i_mtime = timestamp;
|
|
e2inode->i_dtime = 0;
|
|
e2inode->i_gid = 0;
|
|
e2inode->i_links_count = 2;
|
|
e2inode->i_blocks = 0;
|
|
e2inode->i_flags = 0;
|
|
success = writeExt2Inode(inode, *e2inode);
|
|
ASSERT(success);
|
|
|
|
return { id(), inode };
|
|
}
|
|
|