put small subset of e2fsprogs back in the tree:
lsattr, chattr, fsck. Old e2fsprogs tree is in e2fsprogs/old_e2fsprogs/*.
This commit is contained in:
Denis Vlasenko
parent
64c5402584
commit
c4f623ef2a
142 changed files with 42719 additions and 0 deletions
703
e2fsprogs/old_e2fsprogs/ext2fs/unix_io.c
Normal file
703
e2fsprogs/old_e2fsprogs/ext2fs/unix_io.c
Normal file
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@ -0,0 +1,703 @@
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/* vi: set sw=4 ts=4: */
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/*
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* unix_io.c --- This is the Unix (well, really POSIX) implementation
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* of the I/O manager.
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*
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* Implements a one-block write-through cache.
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*
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* Includes support for Windows NT support under Cygwin.
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*
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* Copyright (C) 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001,
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* 2002 by Theodore Ts'o.
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*
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* %Begin-Header%
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* This file may be redistributed under the terms of the GNU Public
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* License.
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* %End-Header%
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*/
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#include <stdio.h>
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#include <string.h>
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#if HAVE_UNISTD_H
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#include <unistd.h>
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#endif
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#if HAVE_ERRNO_H
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#include <errno.h>
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#endif
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#include <fcntl.h>
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#include <time.h>
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#ifdef __linux__
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#include <sys/utsname.h>
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#endif
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#if HAVE_SYS_STAT_H
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#include <sys/stat.h>
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#endif
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#if HAVE_SYS_TYPES_H
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#include <sys/types.h>
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#endif
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#include <sys/resource.h>
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#include "ext2_fs.h"
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#include "ext2fs.h"
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/*
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* For checking structure magic numbers...
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*/
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#define EXT2_CHECK_MAGIC(struct, code) \
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if ((struct)->magic != (code)) return (code)
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struct unix_cache {
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char *buf;
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unsigned long block;
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int access_time;
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unsigned dirty:1;
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unsigned in_use:1;
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};
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#define CACHE_SIZE 8
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#define WRITE_DIRECT_SIZE 4 /* Must be smaller than CACHE_SIZE */
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#define READ_DIRECT_SIZE 4 /* Should be smaller than CACHE_SIZE */
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struct unix_private_data {
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int magic;
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int dev;
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int flags;
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int access_time;
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ext2_loff_t offset;
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struct unix_cache cache[CACHE_SIZE];
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};
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static errcode_t unix_open(const char *name, int flags, io_channel *channel);
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static errcode_t unix_close(io_channel channel);
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static errcode_t unix_set_blksize(io_channel channel, int blksize);
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static errcode_t unix_read_blk(io_channel channel, unsigned long block,
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int count, void *data);
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static errcode_t unix_write_blk(io_channel channel, unsigned long block,
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int count, const void *data);
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static errcode_t unix_flush(io_channel channel);
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static errcode_t unix_write_byte(io_channel channel, unsigned long offset,
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int size, const void *data);
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static errcode_t unix_set_option(io_channel channel, const char *option,
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const char *arg);
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static void reuse_cache(io_channel channel, struct unix_private_data *data,
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struct unix_cache *cache, unsigned long block);
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/* __FreeBSD_kernel__ is defined by GNU/kFreeBSD - the FreeBSD kernel
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* does not know buffered block devices - everything is raw. */
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#if defined(__CYGWIN__) || defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
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#define NEED_BOUNCE_BUFFER
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#else
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#undef NEED_BOUNCE_BUFFER
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#endif
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static struct struct_io_manager struct_unix_manager = {
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EXT2_ET_MAGIC_IO_MANAGER,
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"Unix I/O Manager",
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unix_open,
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unix_close,
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unix_set_blksize,
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unix_read_blk,
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unix_write_blk,
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unix_flush,
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#ifdef NEED_BOUNCE_BUFFER
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0,
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#else
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unix_write_byte,
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#endif
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unix_set_option
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};
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io_manager unix_io_manager = &struct_unix_manager;
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/*
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* Here are the raw I/O functions
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*/
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#ifndef NEED_BOUNCE_BUFFER
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static errcode_t raw_read_blk(io_channel channel,
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struct unix_private_data *data,
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unsigned long block,
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int count, void *buf)
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{
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errcode_t retval;
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ssize_t size;
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ext2_loff_t location;
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int actual = 0;
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size = (count < 0) ? -count : count * channel->block_size;
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location = ((ext2_loff_t) block * channel->block_size) + data->offset;
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if (ext2fs_llseek(data->dev, location, SEEK_SET) != location) {
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retval = errno ? errno : EXT2_ET_LLSEEK_FAILED;
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goto error_out;
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}
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actual = read(data->dev, buf, size);
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if (actual != size) {
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if (actual < 0)
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actual = 0;
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retval = EXT2_ET_SHORT_READ;
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goto error_out;
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}
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return 0;
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error_out:
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memset((char *) buf+actual, 0, size-actual);
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if (channel->read_error)
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retval = (channel->read_error)(channel, block, count, buf,
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size, actual, retval);
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return retval;
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}
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#else /* NEED_BOUNCE_BUFFER */
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/*
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* Windows and FreeBSD block devices only allow sector alignment IO in offset and size
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*/
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static errcode_t raw_read_blk(io_channel channel,
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struct unix_private_data *data,
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unsigned long block,
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int count, void *buf)
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{
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errcode_t retval;
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size_t size, alignsize, fragment;
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ext2_loff_t location;
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int total = 0, actual;
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#define BLOCKALIGN 512
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char sector[BLOCKALIGN];
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size = (count < 0) ? -count : count * channel->block_size;
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location = ((ext2_loff_t) block * channel->block_size) + data->offset;
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#ifdef DEBUG
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printf("count=%d, size=%d, block=%d, blk_size=%d, location=%lx\n",
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count, size, block, channel->block_size, location);
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#endif
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if (ext2fs_llseek(data->dev, location, SEEK_SET) != location) {
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retval = errno ? errno : EXT2_ET_LLSEEK_FAILED;
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goto error_out;
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}
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fragment = size % BLOCKALIGN;
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alignsize = size - fragment;
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if (alignsize) {
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actual = read(data->dev, buf, alignsize);
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if (actual != alignsize)
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goto short_read;
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}
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if (fragment) {
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actual = read(data->dev, sector, BLOCKALIGN);
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if (actual != BLOCKALIGN)
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goto short_read;
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memcpy(buf+alignsize, sector, fragment);
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}
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return 0;
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short_read:
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if (actual>0)
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total += actual;
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retval = EXT2_ET_SHORT_READ;
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error_out:
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memset((char *) buf+total, 0, size-actual);
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if (channel->read_error)
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retval = (channel->read_error)(channel, block, count, buf,
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size, actual, retval);
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return retval;
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}
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#endif
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static errcode_t raw_write_blk(io_channel channel,
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struct unix_private_data *data,
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unsigned long block,
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int count, const void *buf)
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{
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ssize_t size;
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ext2_loff_t location;
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int actual = 0;
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errcode_t retval;
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if (count == 1)
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size = channel->block_size;
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else {
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if (count < 0)
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size = -count;
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else
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size = count * channel->block_size;
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}
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location = ((ext2_loff_t) block * channel->block_size) + data->offset;
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if (ext2fs_llseek(data->dev, location, SEEK_SET) != location) {
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retval = errno ? errno : EXT2_ET_LLSEEK_FAILED;
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goto error_out;
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}
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actual = write(data->dev, buf, size);
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if (actual != size) {
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retval = EXT2_ET_SHORT_WRITE;
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goto error_out;
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}
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return 0;
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error_out:
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if (channel->write_error)
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retval = (channel->write_error)(channel, block, count, buf,
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size, actual, retval);
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return retval;
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}
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/*
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* Here we implement the cache functions
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*/
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/* Allocate the cache buffers */
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static errcode_t alloc_cache(io_channel channel,
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struct unix_private_data *data)
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{
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errcode_t retval;
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struct unix_cache *cache;
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int i;
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data->access_time = 0;
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for (i=0, cache = data->cache; i < CACHE_SIZE; i++, cache++) {
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cache->block = 0;
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cache->access_time = 0;
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cache->dirty = 0;
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cache->in_use = 0;
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if ((retval = ext2fs_get_mem(channel->block_size,
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&cache->buf)))
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return retval;
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}
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return 0;
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}
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/* Free the cache buffers */
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static void free_cache(struct unix_private_data *data)
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{
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struct unix_cache *cache;
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int i;
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data->access_time = 0;
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for (i=0, cache = data->cache; i < CACHE_SIZE; i++, cache++) {
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cache->block = 0;
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cache->access_time = 0;
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cache->dirty = 0;
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cache->in_use = 0;
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ext2fs_free_mem(&cache->buf);
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cache->buf = 0;
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}
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}
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#ifndef NO_IO_CACHE
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/*
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* Try to find a block in the cache. If the block is not found, and
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* eldest is a non-zero pointer, then fill in eldest with the cache
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* entry to that should be reused.
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*/
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static struct unix_cache *find_cached_block(struct unix_private_data *data,
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unsigned long block,
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struct unix_cache **eldest)
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{
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struct unix_cache *cache, *unused_cache, *oldest_cache;
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int i;
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unused_cache = oldest_cache = 0;
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for (i=0, cache = data->cache; i < CACHE_SIZE; i++, cache++) {
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if (!cache->in_use) {
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if (!unused_cache)
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unused_cache = cache;
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continue;
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}
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if (cache->block == block) {
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cache->access_time = ++data->access_time;
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return cache;
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}
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if (!oldest_cache ||
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(cache->access_time < oldest_cache->access_time))
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oldest_cache = cache;
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}
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if (eldest)
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*eldest = (unused_cache) ? unused_cache : oldest_cache;
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return 0;
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||||
}
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||||
|
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/*
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||||
* Reuse a particular cache entry for another block.
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||||
*/
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static void reuse_cache(io_channel channel, struct unix_private_data *data,
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struct unix_cache *cache, unsigned long block)
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||||
{
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||||
if (cache->dirty && cache->in_use)
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raw_write_blk(channel, data, cache->block, 1, cache->buf);
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||||
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cache->in_use = 1;
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cache->dirty = 0;
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cache->block = block;
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||||
cache->access_time = ++data->access_time;
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}
|
||||
|
||||
/*
|
||||
* Flush all of the blocks in the cache
|
||||
*/
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static errcode_t flush_cached_blocks(io_channel channel,
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struct unix_private_data *data,
|
||||
int invalidate)
|
||||
|
||||
{
|
||||
struct unix_cache *cache;
|
||||
errcode_t retval, retval2;
|
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int i;
|
||||
|
||||
retval2 = 0;
|
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for (i=0, cache = data->cache; i < CACHE_SIZE; i++, cache++) {
|
||||
if (!cache->in_use)
|
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continue;
|
||||
|
||||
if (invalidate)
|
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cache->in_use = 0;
|
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|
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if (!cache->dirty)
|
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continue;
|
||||
|
||||
retval = raw_write_blk(channel, data,
|
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cache->block, 1, cache->buf);
|
||||
if (retval)
|
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retval2 = retval;
|
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else
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cache->dirty = 0;
|
||||
}
|
||||
return retval2;
|
||||
}
|
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#endif /* NO_IO_CACHE */
|
||||
|
||||
static errcode_t unix_open(const char *name, int flags, io_channel *channel)
|
||||
{
|
||||
io_channel io = NULL;
|
||||
struct unix_private_data *data = NULL;
|
||||
errcode_t retval;
|
||||
int open_flags;
|
||||
struct stat st;
|
||||
#ifdef __linux__
|
||||
struct utsname ut;
|
||||
#endif
|
||||
|
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if (name == 0)
|
||||
return EXT2_ET_BAD_DEVICE_NAME;
|
||||
retval = ext2fs_get_mem(sizeof(struct struct_io_channel), &io);
|
||||
if (retval)
|
||||
return retval;
|
||||
memset(io, 0, sizeof(struct struct_io_channel));
|
||||
io->magic = EXT2_ET_MAGIC_IO_CHANNEL;
|
||||
retval = ext2fs_get_mem(sizeof(struct unix_private_data), &data);
|
||||
if (retval)
|
||||
goto cleanup;
|
||||
|
||||
io->manager = unix_io_manager;
|
||||
retval = ext2fs_get_mem(strlen(name)+1, &io->name);
|
||||
if (retval)
|
||||
goto cleanup;
|
||||
|
||||
strcpy(io->name, name);
|
||||
io->private_data = data;
|
||||
io->block_size = 1024;
|
||||
io->read_error = 0;
|
||||
io->write_error = 0;
|
||||
io->refcount = 1;
|
||||
|
||||
memset(data, 0, sizeof(struct unix_private_data));
|
||||
data->magic = EXT2_ET_MAGIC_UNIX_IO_CHANNEL;
|
||||
|
||||
if ((retval = alloc_cache(io, data)))
|
||||
goto cleanup;
|
||||
|
||||
open_flags = (flags & IO_FLAG_RW) ? O_RDWR : O_RDONLY;
|
||||
#ifdef CONFIG_LFS
|
||||
data->dev = open64(io->name, open_flags);
|
||||
#else
|
||||
data->dev = open(io->name, open_flags);
|
||||
#endif
|
||||
if (data->dev < 0) {
|
||||
retval = errno;
|
||||
goto cleanup;
|
||||
}
|
||||
|
||||
#ifdef __linux__
|
||||
#undef RLIM_INFINITY
|
||||
#if (defined(__alpha__) || ((defined(__sparc__) || defined(__mips__)) && (SIZEOF_LONG == 4)))
|
||||
#define RLIM_INFINITY ((unsigned long)(~0UL>>1))
|
||||
#else
|
||||
#define RLIM_INFINITY (~0UL)
|
||||
#endif
|
||||
/*
|
||||
* Work around a bug in 2.4.10-2.4.18 kernels where writes to
|
||||
* block devices are wrongly getting hit by the filesize
|
||||
* limit. This workaround isn't perfect, since it won't work
|
||||
* if glibc wasn't built against 2.2 header files. (Sigh.)
|
||||
*
|
||||
*/
|
||||
if ((flags & IO_FLAG_RW) &&
|
||||
(uname(&ut) == 0) &&
|
||||
((ut.release[0] == '2') && (ut.release[1] == '.') &&
|
||||
(ut.release[2] == '4') && (ut.release[3] == '.') &&
|
||||
(ut.release[4] == '1') && (ut.release[5] >= '0') &&
|
||||
(ut.release[5] < '8')) &&
|
||||
(fstat(data->dev, &st) == 0) &&
|
||||
(S_ISBLK(st.st_mode))) {
|
||||
struct rlimit rlim;
|
||||
|
||||
rlim.rlim_cur = rlim.rlim_max = (unsigned long) RLIM_INFINITY;
|
||||
setrlimit(RLIMIT_FSIZE, &rlim);
|
||||
getrlimit(RLIMIT_FSIZE, &rlim);
|
||||
if (((unsigned long) rlim.rlim_cur) <
|
||||
((unsigned long) rlim.rlim_max)) {
|
||||
rlim.rlim_cur = rlim.rlim_max;
|
||||
setrlimit(RLIMIT_FSIZE, &rlim);
|
||||
}
|
||||
}
|
||||
#endif
|
||||
*channel = io;
|
||||
return 0;
|
||||
|
||||
cleanup:
|
||||
if (data) {
|
||||
free_cache(data);
|
||||
ext2fs_free_mem(&data);
|
||||
}
|
||||
ext2fs_free_mem(&io);
|
||||
return retval;
|
||||
}
|
||||
|
||||
static errcode_t unix_close(io_channel channel)
|
||||
{
|
||||
struct unix_private_data *data;
|
||||
errcode_t retval = 0;
|
||||
|
||||
EXT2_CHECK_MAGIC(channel, EXT2_ET_MAGIC_IO_CHANNEL);
|
||||
data = (struct unix_private_data *) channel->private_data;
|
||||
EXT2_CHECK_MAGIC(data, EXT2_ET_MAGIC_UNIX_IO_CHANNEL);
|
||||
|
||||
if (--channel->refcount > 0)
|
||||
return 0;
|
||||
|
||||
#ifndef NO_IO_CACHE
|
||||
retval = flush_cached_blocks(channel, data, 0);
|
||||
#endif
|
||||
|
||||
if (close(data->dev) < 0)
|
||||
retval = errno;
|
||||
free_cache(data);
|
||||
|
||||
ext2fs_free_mem(&channel->private_data);
|
||||
ext2fs_free_mem(&channel->name);
|
||||
ext2fs_free_mem(&channel);
|
||||
return retval;
|
||||
}
|
||||
|
||||
static errcode_t unix_set_blksize(io_channel channel, int blksize)
|
||||
{
|
||||
struct unix_private_data *data;
|
||||
errcode_t retval;
|
||||
|
||||
EXT2_CHECK_MAGIC(channel, EXT2_ET_MAGIC_IO_CHANNEL);
|
||||
data = (struct unix_private_data *) channel->private_data;
|
||||
EXT2_CHECK_MAGIC(data, EXT2_ET_MAGIC_UNIX_IO_CHANNEL);
|
||||
|
||||
if (channel->block_size != blksize) {
|
||||
#ifndef NO_IO_CACHE
|
||||
if ((retval = flush_cached_blocks(channel, data, 0)))
|
||||
return retval;
|
||||
#endif
|
||||
|
||||
channel->block_size = blksize;
|
||||
free_cache(data);
|
||||
if ((retval = alloc_cache(channel, data)))
|
||||
return retval;
|
||||
}
|
||||
return 0;
|
||||
}
|
||||
|
||||
|
||||
static errcode_t unix_read_blk(io_channel channel, unsigned long block,
|
||||
int count, void *buf)
|
||||
{
|
||||
struct unix_private_data *data;
|
||||
struct unix_cache *cache, *reuse[READ_DIRECT_SIZE];
|
||||
errcode_t retval;
|
||||
char *cp;
|
||||
int i, j;
|
||||
|
||||
EXT2_CHECK_MAGIC(channel, EXT2_ET_MAGIC_IO_CHANNEL);
|
||||
data = (struct unix_private_data *) channel->private_data;
|
||||
EXT2_CHECK_MAGIC(data, EXT2_ET_MAGIC_UNIX_IO_CHANNEL);
|
||||
|
||||
#ifdef NO_IO_CACHE
|
||||
return raw_read_blk(channel, data, block, count, buf);
|
||||
#else
|
||||
/*
|
||||
* If we're doing an odd-sized read or a very large read,
|
||||
* flush out the cache and then do a direct read.
|
||||
*/
|
||||
if (count < 0 || count > WRITE_DIRECT_SIZE) {
|
||||
if ((retval = flush_cached_blocks(channel, data, 0)))
|
||||
return retval;
|
||||
return raw_read_blk(channel, data, block, count, buf);
|
||||
}
|
||||
|
||||
cp = buf;
|
||||
while (count > 0) {
|
||||
/* If it's in the cache, use it! */
|
||||
if ((cache = find_cached_block(data, block, &reuse[0]))) {
|
||||
#ifdef DEBUG
|
||||
printf("Using cached block %d\n", block);
|
||||
#endif
|
||||
memcpy(cp, cache->buf, channel->block_size);
|
||||
count--;
|
||||
block++;
|
||||
cp += channel->block_size;
|
||||
continue;
|
||||
}
|
||||
/*
|
||||
* Find the number of uncached blocks so we can do a
|
||||
* single read request
|
||||
*/
|
||||
for (i=1; i < count; i++)
|
||||
if (find_cached_block(data, block+i, &reuse[i]))
|
||||
break;
|
||||
#ifdef DEBUG
|
||||
printf("Reading %d blocks starting at %d\n", i, block);
|
||||
#endif
|
||||
if ((retval = raw_read_blk(channel, data, block, i, cp)))
|
||||
return retval;
|
||||
|
||||
/* Save the results in the cache */
|
||||
for (j=0; j < i; j++) {
|
||||
count--;
|
||||
cache = reuse[j];
|
||||
reuse_cache(channel, data, cache, block++);
|
||||
memcpy(cache->buf, cp, channel->block_size);
|
||||
cp += channel->block_size;
|
||||
}
|
||||
}
|
||||
return 0;
|
||||
#endif /* NO_IO_CACHE */
|
||||
}
|
||||
|
||||
static errcode_t unix_write_blk(io_channel channel, unsigned long block,
|
||||
int count, const void *buf)
|
||||
{
|
||||
struct unix_private_data *data;
|
||||
struct unix_cache *cache, *reuse;
|
||||
errcode_t retval = 0;
|
||||
const char *cp;
|
||||
int writethrough;
|
||||
|
||||
EXT2_CHECK_MAGIC(channel, EXT2_ET_MAGIC_IO_CHANNEL);
|
||||
data = (struct unix_private_data *) channel->private_data;
|
||||
EXT2_CHECK_MAGIC(data, EXT2_ET_MAGIC_UNIX_IO_CHANNEL);
|
||||
|
||||
#ifdef NO_IO_CACHE
|
||||
return raw_write_blk(channel, data, block, count, buf);
|
||||
#else
|
||||
/*
|
||||
* If we're doing an odd-sized write or a very large write,
|
||||
* flush out the cache completely and then do a direct write.
|
||||
*/
|
||||
if (count < 0 || count > WRITE_DIRECT_SIZE) {
|
||||
if ((retval = flush_cached_blocks(channel, data, 1)))
|
||||
return retval;
|
||||
return raw_write_blk(channel, data, block, count, buf);
|
||||
}
|
||||
|
||||
/*
|
||||
* For a moderate-sized multi-block write, first force a write
|
||||
* if we're in write-through cache mode, and then fill the
|
||||
* cache with the blocks.
|
||||
*/
|
||||
writethrough = channel->flags & CHANNEL_FLAGS_WRITETHROUGH;
|
||||
if (writethrough)
|
||||
retval = raw_write_blk(channel, data, block, count, buf);
|
||||
|
||||
cp = buf;
|
||||
while (count > 0) {
|
||||
cache = find_cached_block(data, block, &reuse);
|
||||
if (!cache) {
|
||||
cache = reuse;
|
||||
reuse_cache(channel, data, cache, block);
|
||||
}
|
||||
memcpy(cache->buf, cp, channel->block_size);
|
||||
cache->dirty = !writethrough;
|
||||
count--;
|
||||
block++;
|
||||
cp += channel->block_size;
|
||||
}
|
||||
return retval;
|
||||
#endif /* NO_IO_CACHE */
|
||||
}
|
||||
|
||||
static errcode_t unix_write_byte(io_channel channel, unsigned long offset,
|
||||
int size, const void *buf)
|
||||
{
|
||||
struct unix_private_data *data;
|
||||
errcode_t retval = 0;
|
||||
ssize_t actual;
|
||||
|
||||
EXT2_CHECK_MAGIC(channel, EXT2_ET_MAGIC_IO_CHANNEL);
|
||||
data = (struct unix_private_data *) channel->private_data;
|
||||
EXT2_CHECK_MAGIC(data, EXT2_ET_MAGIC_UNIX_IO_CHANNEL);
|
||||
|
||||
#ifndef NO_IO_CACHE
|
||||
/*
|
||||
* Flush out the cache completely
|
||||
*/
|
||||
if ((retval = flush_cached_blocks(channel, data, 1)))
|
||||
return retval;
|
||||
#endif
|
||||
|
||||
if (lseek(data->dev, offset + data->offset, SEEK_SET) < 0)
|
||||
return errno;
|
||||
|
||||
actual = write(data->dev, buf, size);
|
||||
if (actual != size)
|
||||
return EXT2_ET_SHORT_WRITE;
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
/*
|
||||
* Flush data buffers to disk.
|
||||
*/
|
||||
static errcode_t unix_flush(io_channel channel)
|
||||
{
|
||||
struct unix_private_data *data;
|
||||
errcode_t retval = 0;
|
||||
|
||||
EXT2_CHECK_MAGIC(channel, EXT2_ET_MAGIC_IO_CHANNEL);
|
||||
data = (struct unix_private_data *) channel->private_data;
|
||||
EXT2_CHECK_MAGIC(data, EXT2_ET_MAGIC_UNIX_IO_CHANNEL);
|
||||
|
||||
#ifndef NO_IO_CACHE
|
||||
retval = flush_cached_blocks(channel, data, 0);
|
||||
#endif
|
||||
fsync(data->dev);
|
||||
return retval;
|
||||
}
|
||||
|
||||
static errcode_t unix_set_option(io_channel channel, const char *option,
|
||||
const char *arg)
|
||||
{
|
||||
struct unix_private_data *data;
|
||||
unsigned long tmp;
|
||||
char *end;
|
||||
|
||||
EXT2_CHECK_MAGIC(channel, EXT2_ET_MAGIC_IO_CHANNEL);
|
||||
data = (struct unix_private_data *) channel->private_data;
|
||||
EXT2_CHECK_MAGIC(data, EXT2_ET_MAGIC_UNIX_IO_CHANNEL);
|
||||
|
||||
if (!strcmp(option, "offset")) {
|
||||
if (!arg)
|
||||
return EXT2_ET_INVALID_ARGUMENT;
|
||||
|
||||
tmp = strtoul(arg, &end, 0);
|
||||
if (*end)
|
||||
return EXT2_ET_INVALID_ARGUMENT;
|
||||
data->offset = tmp;
|
||||
return 0;
|
||||
}
|
||||
return EXT2_ET_INVALID_ARGUMENT;
|
||||
}
|
||||
Loading…
Add table
Add a link
Reference in a new issue