WSL2-Linux-Kernel/fs/devfs/util.c

98 строки
3.9 KiB
C

/* devfs (Device FileSystem) utilities.
Copyright (C) 1999-2002 Richard Gooch
This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Library General Public
License as published by the Free Software Foundation; either
version 2 of the License, or (at your option) any later version.
This library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with this library; if not, write to the Free
Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
Richard Gooch may be reached by email at rgooch@atnf.csiro.au
The postal address is:
Richard Gooch, c/o ATNF, P. O. Box 76, Epping, N.S.W., 2121, Australia.
ChangeLog
19991031 Richard Gooch <rgooch@atnf.csiro.au>
Created.
19991103 Richard Gooch <rgooch@atnf.csiro.au>
Created <_devfs_convert_name> and supported SCSI and IDE CD-ROMs
20000203 Richard Gooch <rgooch@atnf.csiro.au>
Changed operations pointer type to void *.
20000621 Richard Gooch <rgooch@atnf.csiro.au>
Changed interface to <devfs_register_series>.
20000622 Richard Gooch <rgooch@atnf.csiro.au>
Took account of interface change to <devfs_mk_symlink>.
Took account of interface change to <devfs_mk_dir>.
20010519 Richard Gooch <rgooch@atnf.csiro.au>
Documentation cleanup.
20010709 Richard Gooch <rgooch@atnf.csiro.au>
Created <devfs_*alloc_major> and <devfs_*alloc_devnum>.
20010710 Richard Gooch <rgooch@atnf.csiro.au>
Created <devfs_*alloc_unique_number>.
20010730 Richard Gooch <rgooch@atnf.csiro.au>
Documentation typo fix.
20010806 Richard Gooch <rgooch@atnf.csiro.au>
Made <block_semaphore> and <char_semaphore> private.
20010813 Richard Gooch <rgooch@atnf.csiro.au>
Fixed bug in <devfs_alloc_unique_number>: limited to 128 numbers
20010818 Richard Gooch <rgooch@atnf.csiro.au>
Updated major masks up to Linus' "no new majors" proclamation.
Block: were 126 now 122 free, char: were 26 now 19 free.
20020324 Richard Gooch <rgooch@atnf.csiro.au>
Fixed bug in <devfs_alloc_unique_number>: was clearing beyond
bitfield.
20020326 Richard Gooch <rgooch@atnf.csiro.au>
Fixed bitfield data type for <devfs_*alloc_devnum>.
Made major bitfield type and initialiser 64 bit safe.
20020413 Richard Gooch <rgooch@atnf.csiro.au>
Fixed shift warning on 64 bit machines.
20020428 Richard Gooch <rgooch@atnf.csiro.au>
Copied and used macro for error messages from fs/devfs/base.c
20021013 Richard Gooch <rgooch@atnf.csiro.au>
Documentation fix.
20030101 Adam J. Richter <adam@yggdrasil.com>
Eliminate DEVFS_SPECIAL_{CHR,BLK}. Use mode_t instead.
20030106 Christoph Hellwig <hch@infradead.org>
Rewrite devfs_{,de}alloc_devnum to look like C code.
*/
#include <linux/module.h>
#include <linux/init.h>
#include <linux/devfs_fs_kernel.h>
#include <linux/slab.h>
#include <linux/vmalloc.h>
#include <linux/genhd.h>
#include <linux/bitops.h>
int devfs_register_tape(const char *name)
{
char tname[32], dest[64];
static unsigned int tape_counter;
unsigned int n = tape_counter++;
sprintf(dest, "../%s", name);
sprintf(tname, "tapes/tape%u", n);
devfs_mk_symlink(tname, dest);
return n;
}
EXPORT_SYMBOL(devfs_register_tape);
void devfs_unregister_tape(int num)
{
if (num >= 0)
devfs_remove("tapes/tape%u", num);
}
EXPORT_SYMBOL(devfs_unregister_tape);