MaxOS::filesystem::format::ext2::InodeHandler Class Reference

Simplfies the management of an inode & its blocks. More...

#include <ext2.h>

Public Member Functions
	InodeHandler (Ext2Volume *volume, uint32_t inode)
	Construct a new Inode Handler object. Reads the inode and caches the block pointers.
size_t	size () const
	read the size upper and lower into a single size_t
void	set_size (size_t size)
	store the size of the inode data. (does not write to disk)
size_t	grow (size_t amount, bool flush=true)
	Increase the size of the inode's storage capacity by allocating new blocks.
void	save ()
	Writes the inode meta data to disk.
void	free ()
	Marks this inode's blocks as free and then the inode as free.

Public Attributes
uint32_t	inode_number
	The index of the inode.
inode_t	inode
	The inode metadata for this file/directory.
common::Vector< uint32_t >	block_cache
	All the blocks used by this inode.

Detailed Description

Simplfies the management of an inode & its blocks.

Definition at line 372 of file ext2.h.

Constructor & Destructor Documentation

InodeHandler()

InodeHandler::InodeHandler	(	Ext2Volume *	volume,
		uint32_t	inode_index
	)

Construct a new Inode Handler object. Reads the inode and caches the block pointers.

Parameters

volume	The volume the inode belongs to
inode_index	The inode index

Definition at line 509 of file ext2.cpp.

        : m_volume(volume),
        inode_number(inode_index),
        inode(m_volume->read_inode(inode_number)) {
 
    // Read the block pointers
    for(uint32_t direct_pointer = 0; direct_pointer < 12; ++direct_pointer)
        if(inode.block_pointers[direct_pointer])
            block_cache.push_back(inode.block_pointers[direct_pointer]);
 
    buffer_t buffer(m_volume->block_size);
    parse_indirect(1, inode.l1_indirect, &buffer);
    parse_indirect(2, inode.l2_indirect, &buffer);
    parse_indirect(3, inode.l3_indirect, &buffer);
}

References block_cache, MaxOS::filesystem::format::ext2::Ext2Volume::block_size, inode, and MaxOS::common::Vector< Type >::push_back().

Member Function Documentation

free()

void InodeHandler::free

(

)

Marks this inode's blocks as free and then the inode as free.

Definition at line 705 of file ext2.cpp.

                        {
 
    m_volume->ext2_lock.lock();
 
    // Free the inode
    m_volume->free_blocks(block_cache);
    m_volume->free_inode(inode_number);
 
    m_volume->ext2_lock.unlock();
}

References block_cache, MaxOS::filesystem::format::ext2::Ext2Volume::ext2_lock, MaxOS::filesystem::format::ext2::Ext2Volume::free_blocks(), MaxOS::filesystem::format::ext2::Ext2Volume::free_inode(), inode_number, MaxOS::common::Spinlock::lock(), and MaxOS::common::Spinlock::unlock().

grow()

size_t InodeHandler::grow	(	size_t	amount,
		bool	flush = true
	)

Increase the size of the inode's storage capacity by allocating new blocks.

Parameters

amount	The amount to grow to in bytes
flush	Save the newly allocated chunks to disk, defaults to true

Returns

The new toatal size of the file (size() + amount)

Todo:

Should this return size() instead?

Definition at line 675 of file ext2.cpp.

                                                   {
 
    // Nothing to grow
    if(amount <= 0)
        return size();
 
    // Allocate new blocks
    auto blocks = m_volume->allocate_blocks(m_volume->bytes_to_blocks(amount));
    ASSERT(blocks[0] != 0, "Failed to allocate new blocks for file");
 
    // Save the changes
    store_blocks(blocks);
    set_size(size() + amount);
    if(flush)
        save();
 
    return size() + amount;
}

References MaxOS::filesystem::format::ext2::Ext2Volume::allocate_blocks(), ASSERT, MaxOS::filesystem::format::ext2::Ext2Volume::bytes_to_blocks(), save(), set_size(), and size().

Referenced by MaxOS::filesystem::format::ext2::Ext2File::write().

save()

void InodeHandler::save

(

)

Writes the inode meta data to disk.

Definition at line 697 of file ext2.cpp.

                        {
 
    m_volume->write_inode(inode_number, &inode);
}

References inode, inode_number, and MaxOS::filesystem::format::ext2::Ext2Volume::write_inode().

Referenced by grow(), and MaxOS::filesystem::format::ext2::Ext2File::write().

set_size()

void InodeHandler::set_size

(

size_t

size

)

store the size of the inode data. (does not write to disk)

Parameters

size	The new size

Definition at line 537 of file ext2.cpp.

                                       {
 
    inode.size_lower = (uint32_t) (size & 0xFFFFFFFFULL);
    inode.size_upper = (uint32_t) (size >> 32);
 
}

References inode, and size().

Referenced by grow().

size()

size_t InodeHandler::size

(

)

const

read the size upper and lower into a single size_t

Returns

The size of the inode data (not the inode itself)

Definition at line 529 of file ext2.cpp.

                                {
    return ((size_t) inode.size_upper << 32) | (size_t) inode.size_lower;
}

References inode.

Referenced by MaxOS::filesystem::format::ext2::Ext2File::Ext2File(), grow(), and set_size().

Member Data Documentation

block_cache

common::Vector<uint32_t> MaxOS::filesystem::format::ext2::InodeHandler::block_cache

All the blocks used by this inode.

Definition at line 387 of file ext2.h.

Referenced by free(), InodeHandler(), MaxOS::filesystem::format::ext2::Ext2File::read(), MaxOS::filesystem::format::ext2::Ext2Directory::read_from_disk(), and MaxOS::filesystem::format::ext2::Ext2File::write().

inode

inode_t MaxOS::filesystem::format::ext2::InodeHandler::inode

The inode metadata for this file/directory.

Definition at line 386 of file ext2.h.

Referenced by InodeHandler(), save(), set_size(), size(), and MaxOS::filesystem::format::ext2::Ext2File::write().

inode_number

uint32_t MaxOS::filesystem::format::ext2::InodeHandler::inode_number

The index of the inode.

Definition at line 385 of file ext2.h.

Referenced by MaxOS::filesystem::format::ext2::Ext2Directory::create_subdirectory(), free(), and save().

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The documentation for this class was generated from the following files:

• /home/runner/work/MaxOS/MaxOS/kernel/include/filesystem/format/ext2.h
• /home/runner/work/MaxOS/MaxOS/kernel/src/filesystem/format/ext2.cpp