mirror of
https://github.com/Fledge68/WiiFlow_Lite.git
synced 2024-11-24 12:19:16 +01:00
336 lines
7.8 KiB
C
336 lines
7.8 KiB
C
|
/*
|
||
|
* bmap.c --- logical to physical block mapping
|
||
|
*
|
||
|
* Copyright (C) 1997 Theodore Ts'o.
|
||
|
*
|
||
|
* %Begin-Header%
|
||
|
* This file may be redistributed under the terms of the GNU Library
|
||
|
* General Public License, version 2.
|
||
|
* %End-Header%
|
||
|
*/
|
||
|
|
||
|
#include <stdio.h>
|
||
|
#include <string.h>
|
||
|
#if HAVE_UNISTD_H
|
||
|
#include <unistd.h>
|
||
|
#endif
|
||
|
#include <errno.h>
|
||
|
|
||
|
#include "ext2_fs.h"
|
||
|
#include "ext2fs.h"
|
||
|
|
||
|
#if defined(__GNUC__) && !defined(NO_INLINE_FUNCS)
|
||
|
#define _BMAP_INLINE_ __inline__
|
||
|
#else
|
||
|
#define _BMAP_INLINE_
|
||
|
#endif
|
||
|
|
||
|
extern errcode_t ext2fs_bmap(ext2_filsys fs, ext2_ino_t ino,
|
||
|
struct ext2_inode *inode,
|
||
|
char *block_buf, int bmap_flags,
|
||
|
blk_t block, blk_t *phys_blk);
|
||
|
|
||
|
#define inode_bmap(inode, nr) ((inode)->i_block[(nr)])
|
||
|
|
||
|
static _BMAP_INLINE_ errcode_t block_ind_bmap(ext2_filsys fs, int flags,
|
||
|
blk_t ind, char *block_buf,
|
||
|
int *blocks_alloc,
|
||
|
blk_t nr, blk_t *ret_blk)
|
||
|
{
|
||
|
errcode_t retval;
|
||
|
blk_t b;
|
||
|
|
||
|
if (!ind) {
|
||
|
if (flags & BMAP_SET)
|
||
|
return EXT2_ET_SET_BMAP_NO_IND;
|
||
|
*ret_blk = 0;
|
||
|
return 0;
|
||
|
}
|
||
|
retval = io_channel_read_blk(fs->io, ind, 1, block_buf);
|
||
|
if (retval)
|
||
|
return retval;
|
||
|
|
||
|
if (flags & BMAP_SET) {
|
||
|
b = *ret_blk;
|
||
|
#ifdef WORDS_BIGENDIAN
|
||
|
b = ext2fs_swab32(b);
|
||
|
#endif
|
||
|
((blk_t *) block_buf)[nr] = b;
|
||
|
return io_channel_write_blk(fs->io, ind, 1, block_buf);
|
||
|
}
|
||
|
|
||
|
b = ((blk_t *) block_buf)[nr];
|
||
|
|
||
|
#ifdef WORDS_BIGENDIAN
|
||
|
b = ext2fs_swab32(b);
|
||
|
#endif
|
||
|
|
||
|
if (!b && (flags & BMAP_ALLOC)) {
|
||
|
b = nr ? ((blk_t *) block_buf)[nr-1] : 0;
|
||
|
retval = ext2fs_alloc_block(fs, b,
|
||
|
block_buf + fs->blocksize, &b);
|
||
|
if (retval)
|
||
|
return retval;
|
||
|
|
||
|
#ifdef WORDS_BIGENDIAN
|
||
|
((blk_t *) block_buf)[nr] = ext2fs_swab32(b);
|
||
|
#else
|
||
|
((blk_t *) block_buf)[nr] = b;
|
||
|
#endif
|
||
|
|
||
|
retval = io_channel_write_blk(fs->io, ind, 1, block_buf);
|
||
|
if (retval)
|
||
|
return retval;
|
||
|
|
||
|
(*blocks_alloc)++;
|
||
|
}
|
||
|
|
||
|
*ret_blk = b;
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
static _BMAP_INLINE_ errcode_t block_dind_bmap(ext2_filsys fs, int flags,
|
||
|
blk_t dind, char *block_buf,
|
||
|
int *blocks_alloc,
|
||
|
blk_t nr, blk_t *ret_blk)
|
||
|
{
|
||
|
blk_t b;
|
||
|
errcode_t retval;
|
||
|
blk_t addr_per_block;
|
||
|
|
||
|
addr_per_block = (blk_t) fs->blocksize >> 2;
|
||
|
|
||
|
retval = block_ind_bmap(fs, flags & ~BMAP_SET, dind, block_buf,
|
||
|
blocks_alloc, nr / addr_per_block, &b);
|
||
|
if (retval)
|
||
|
return retval;
|
||
|
retval = block_ind_bmap(fs, flags, b, block_buf, blocks_alloc,
|
||
|
nr % addr_per_block, ret_blk);
|
||
|
return retval;
|
||
|
}
|
||
|
|
||
|
static _BMAP_INLINE_ errcode_t block_tind_bmap(ext2_filsys fs, int flags,
|
||
|
blk_t tind, char *block_buf,
|
||
|
int *blocks_alloc,
|
||
|
blk_t nr, blk_t *ret_blk)
|
||
|
{
|
||
|
blk_t b;
|
||
|
errcode_t retval;
|
||
|
blk_t addr_per_block;
|
||
|
|
||
|
addr_per_block = (blk_t) fs->blocksize >> 2;
|
||
|
|
||
|
retval = block_dind_bmap(fs, flags & ~BMAP_SET, tind, block_buf,
|
||
|
blocks_alloc, nr / addr_per_block, &b);
|
||
|
if (retval)
|
||
|
return retval;
|
||
|
retval = block_ind_bmap(fs, flags, b, block_buf, blocks_alloc,
|
||
|
nr % addr_per_block, ret_blk);
|
||
|
return retval;
|
||
|
}
|
||
|
|
||
|
errcode_t ext2fs_bmap2(ext2_filsys fs, ext2_ino_t ino, struct ext2_inode *inode,
|
||
|
char *block_buf, int bmap_flags, blk64_t block,
|
||
|
int *ret_flags, blk64_t *phys_blk)
|
||
|
{
|
||
|
struct ext2_inode inode_buf;
|
||
|
ext2_extent_handle_t handle = 0;
|
||
|
blk_t addr_per_block;
|
||
|
blk_t b, blk32;
|
||
|
char *buf = 0;
|
||
|
errcode_t retval = 0;
|
||
|
int blocks_alloc = 0, inode_dirty = 0;
|
||
|
|
||
|
if (!(bmap_flags & BMAP_SET))
|
||
|
*phys_blk = 0;
|
||
|
|
||
|
if (ret_flags)
|
||
|
*ret_flags = 0;
|
||
|
|
||
|
/* Read inode structure if necessary */
|
||
|
if (!inode) {
|
||
|
retval = ext2fs_read_inode(fs, ino, &inode_buf);
|
||
|
if (retval)
|
||
|
return retval;
|
||
|
inode = &inode_buf;
|
||
|
}
|
||
|
addr_per_block = (blk_t) fs->blocksize >> 2;
|
||
|
|
||
|
if (inode->i_flags & EXT4_EXTENTS_FL) {
|
||
|
struct ext2fs_extent extent;
|
||
|
unsigned int offset;
|
||
|
|
||
|
retval = ext2fs_extent_open2(fs, ino, inode, &handle);
|
||
|
if (retval)
|
||
|
goto done;
|
||
|
if (bmap_flags & BMAP_SET) {
|
||
|
retval = ext2fs_extent_set_bmap(handle, block,
|
||
|
*phys_blk, 0);
|
||
|
goto done;
|
||
|
}
|
||
|
retval = ext2fs_extent_goto(handle, block);
|
||
|
if (retval) {
|
||
|
/* If the extent is not found, return phys_blk = 0 */
|
||
|
if (retval == EXT2_ET_EXTENT_NOT_FOUND)
|
||
|
goto got_block;
|
||
|
goto done;
|
||
|
}
|
||
|
retval = ext2fs_extent_get(handle, EXT2_EXTENT_CURRENT, &extent);
|
||
|
if (retval)
|
||
|
goto done;
|
||
|
offset = block - extent.e_lblk;
|
||
|
if (block >= extent.e_lblk && (offset <= extent.e_len)) {
|
||
|
*phys_blk = extent.e_pblk + offset;
|
||
|
if (ret_flags && extent.e_flags & EXT2_EXTENT_FLAGS_UNINIT)
|
||
|
*ret_flags |= BMAP_RET_UNINIT;
|
||
|
}
|
||
|
got_block:
|
||
|
if ((*phys_blk == 0) && (bmap_flags & BMAP_ALLOC)) {
|
||
|
retval = ext2fs_alloc_block(fs, b, block_buf, &b);
|
||
|
if (retval)
|
||
|
goto done;
|
||
|
retval = ext2fs_extent_set_bmap(handle, block,
|
||
|
(blk64_t) b, 0);
|
||
|
if (retval)
|
||
|
goto done;
|
||
|
/* Update inode after setting extent */
|
||
|
retval = ext2fs_read_inode(fs, ino, inode);
|
||
|
if (retval)
|
||
|
return retval;
|
||
|
blocks_alloc++;
|
||
|
*phys_blk = b;
|
||
|
}
|
||
|
retval = 0;
|
||
|
goto done;
|
||
|
}
|
||
|
|
||
|
if (!block_buf) {
|
||
|
retval = ext2fs_get_array(2, fs->blocksize, &buf);
|
||
|
if (retval)
|
||
|
return retval;
|
||
|
block_buf = buf;
|
||
|
}
|
||
|
|
||
|
if (block < EXT2_NDIR_BLOCKS) {
|
||
|
if (bmap_flags & BMAP_SET) {
|
||
|
b = *phys_blk;
|
||
|
inode_bmap(inode, block) = b;
|
||
|
inode_dirty++;
|
||
|
goto done;
|
||
|
}
|
||
|
|
||
|
*phys_blk = inode_bmap(inode, block);
|
||
|
b = block ? inode_bmap(inode, block-1) : 0;
|
||
|
|
||
|
if ((*phys_blk == 0) && (bmap_flags & BMAP_ALLOC)) {
|
||
|
retval = ext2fs_alloc_block(fs, b, block_buf, &b);
|
||
|
if (retval)
|
||
|
goto done;
|
||
|
inode_bmap(inode, block) = b;
|
||
|
blocks_alloc++;
|
||
|
*phys_blk = b;
|
||
|
}
|
||
|
goto done;
|
||
|
}
|
||
|
|
||
|
/* Indirect block */
|
||
|
block -= EXT2_NDIR_BLOCKS;
|
||
|
blk32 = *phys_blk;
|
||
|
if (block < addr_per_block) {
|
||
|
b = inode_bmap(inode, EXT2_IND_BLOCK);
|
||
|
if (!b) {
|
||
|
if (!(bmap_flags & BMAP_ALLOC)) {
|
||
|
if (bmap_flags & BMAP_SET)
|
||
|
retval = EXT2_ET_SET_BMAP_NO_IND;
|
||
|
goto done;
|
||
|
}
|
||
|
|
||
|
b = inode_bmap(inode, EXT2_IND_BLOCK-1);
|
||
|
retval = ext2fs_alloc_block(fs, b, block_buf, &b);
|
||
|
if (retval)
|
||
|
goto done;
|
||
|
inode_bmap(inode, EXT2_IND_BLOCK) = b;
|
||
|
blocks_alloc++;
|
||
|
}
|
||
|
retval = block_ind_bmap(fs, bmap_flags, b, block_buf,
|
||
|
&blocks_alloc, block, &blk32);
|
||
|
if (retval == 0)
|
||
|
*phys_blk = blk32;
|
||
|
goto done;
|
||
|
}
|
||
|
|
||
|
/* Doubly indirect block */
|
||
|
block -= addr_per_block;
|
||
|
if (block < addr_per_block * addr_per_block) {
|
||
|
b = inode_bmap(inode, EXT2_DIND_BLOCK);
|
||
|
if (!b) {
|
||
|
if (!(bmap_flags & BMAP_ALLOC)) {
|
||
|
if (bmap_flags & BMAP_SET)
|
||
|
retval = EXT2_ET_SET_BMAP_NO_IND;
|
||
|
goto done;
|
||
|
}
|
||
|
|
||
|
b = inode_bmap(inode, EXT2_IND_BLOCK);
|
||
|
retval = ext2fs_alloc_block(fs, b, block_buf, &b);
|
||
|
if (retval)
|
||
|
goto done;
|
||
|
inode_bmap(inode, EXT2_DIND_BLOCK) = b;
|
||
|
blocks_alloc++;
|
||
|
}
|
||
|
retval = block_dind_bmap(fs, bmap_flags, b, block_buf,
|
||
|
&blocks_alloc, block, &blk32);
|
||
|
if (retval == 0)
|
||
|
*phys_blk = blk32;
|
||
|
goto done;
|
||
|
}
|
||
|
|
||
|
/* Triply indirect block */
|
||
|
block -= addr_per_block * addr_per_block;
|
||
|
b = inode_bmap(inode, EXT2_TIND_BLOCK);
|
||
|
if (!b) {
|
||
|
if (!(bmap_flags & BMAP_ALLOC)) {
|
||
|
if (bmap_flags & BMAP_SET)
|
||
|
retval = EXT2_ET_SET_BMAP_NO_IND;
|
||
|
goto done;
|
||
|
}
|
||
|
|
||
|
b = inode_bmap(inode, EXT2_DIND_BLOCK);
|
||
|
retval = ext2fs_alloc_block(fs, b, block_buf, &b);
|
||
|
if (retval)
|
||
|
goto done;
|
||
|
inode_bmap(inode, EXT2_TIND_BLOCK) = b;
|
||
|
blocks_alloc++;
|
||
|
}
|
||
|
retval = block_tind_bmap(fs, bmap_flags, b, block_buf,
|
||
|
&blocks_alloc, block, &blk32);
|
||
|
if (retval == 0)
|
||
|
*phys_blk = blk32;
|
||
|
done:
|
||
|
if (buf)
|
||
|
ext2fs_free_mem(&buf);
|
||
|
if (handle)
|
||
|
ext2fs_extent_free(handle);
|
||
|
if ((retval == 0) && (blocks_alloc || inode_dirty)) {
|
||
|
ext2fs_iblk_add_blocks(fs, inode, blocks_alloc);
|
||
|
retval = ext2fs_write_inode(fs, ino, inode);
|
||
|
}
|
||
|
return retval;
|
||
|
}
|
||
|
|
||
|
errcode_t ext2fs_bmap(ext2_filsys fs, ext2_ino_t ino, struct ext2_inode *inode,
|
||
|
char *block_buf, int bmap_flags, blk_t block,
|
||
|
blk_t *phys_blk)
|
||
|
{
|
||
|
errcode_t ret;
|
||
|
blk64_t ret_blk = *phys_blk;
|
||
|
|
||
|
ret = ext2fs_bmap2(fs, ino, inode, block_buf, bmap_flags, block,
|
||
|
0, &ret_blk);
|
||
|
if (ret)
|
||
|
return ret;
|
||
|
if (ret_blk >= ((long long) 1 << 32))
|
||
|
return EOVERFLOW;
|
||
|
*phys_blk = ret_blk;
|
||
|
return 0;
|
||
|
}
|