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/* -*- auto-fill -*-                                                         */
===============================================================================
Changes for patch v1

- creation of devfs

- modified miscellaneous character devices to support devfs
===============================================================================
Changes for patch v2

- bug fix with manual inode creation
===============================================================================
Changes for patch v3

- bugfixes

- documentation improvements

- created a couple of scripts (one to save&restore a devfs and the
  other to set up compatibility symlinks)

- devfs support for SCSI discs. New name format is: sd_hHcCiIlL
===============================================================================
Changes for patch v4

- bugfix for the directory reading code

- bugfix for compilation with kerneld

- devfs support for generic hard discs

- rationalisation of the various watchdog drivers
===============================================================================
Changes for patch v5

- support for mounting directly from entries in the devfs (it doesn't
  need to be mounted to do this), including the root filesystem.
  Mounting of swap partitions also works. Hence, now if you set
  CONFIG_DEVFS_ONLY to 'Y' then you won't be able to access your discs
  via ordinary device nodes. Naturally, the default is 'N' so that you
  can still use your old device nodes.  If you want to mount from devfs
  entries, make sure you use: append = "root=/dev/sd_..." in your
  lilo.conf. It seems LILO looks for the device number (major&minor)
  and writes that into the kernel image :-( 

- support for character memory devices (/dev/null, /dev/zero, /dev/full
  and so on). Thanks to C. Scott Ananian <cananian@alumni.princeton.edu>
===============================================================================
Changes for patch v6

- support for subdirectories

- support for symbolic links (created by devfs_mk_symlink(), no
  support yet for creation via symlink(2))

- SCSI disc naming now cast in stone, with the format:
  /dev/sd/c0b1t2u3	controller=0, bus=1, ID=2, LUN=3, whole disc
  /dev/sd/c0b1t2u3p4	controller=0, bus=1, ID=2, LUN=3, 4th partition

- loop devices now appear in devfs

- tty devices, console, serial ports, etc. now appear in devfs
  Thanks to C. Scott Ananian <cananian@alumni.princeton.edu>

- bugs with mounting devfs-only devices now fixed
===============================================================================
Changes for patch v7

- SCSI CD-ROMS, tapes and generic devices now appear in devfs
===============================================================================
Changes for patch v8

- bugfix with no-rewind SCSI tapes

- RAMDISCs now appear in devfs

- better cleaning up of devfs entries created by various modules

- interface change to <devfs_register>
===============================================================================
Changes for patch v9

- the v8 patch was corrupted somehow, which would affect the patch for
  linux/fs/filesystems.c
  I've also fixed the v8 patch file on the WWW

- MetaDevices (/dev/md*) should now appear in devfs
===============================================================================
Changes for patch v10

- bugfix in meta device support for devfs

- created this ChangeLog file

- added devfs support to the floppy driver

- added support for creating sockets in a devfs
===============================================================================
Changes for patch v11

- added DEVFS_FL_HIDE_UNREG flag

- incorporated better patch for ttyname() in libc 5.4.43 from H.J. Lu.

- interface change to <devfs_mk_symlink>

- support for creating symlinks with symlink(2)

- parallel port printer (/dev/lp*) now appears in devfs
===============================================================================
Changes for patch v12

- added inode check to <devfs_fill_file> function

- improved devfs support when mounting from devfs

- added call to <<release>> operation when removing swap areas on
  devfs devices

- increased NR_SUPER to 128 to support large numbers of devfs mounts
  (for chroot(2) gaols)

- fixed bug in SCSI disc support: was generating incorrect minors if
  SCSI ID's did not start at 0 and increase by 1

- support symlink traversal when mounting root
===============================================================================
Changes for patch v13

- added devfs support to soundcard driver
  Thanks to Eric Dumas <dumas@linux.eu.org> and
  C. Scott Ananian <cananian@alumni.princeton.edu>

- added devfs support to the joystick driver

- loop driver now has it's own subdirectory "/dev/loop/"

- created <devfs_get_flags> and <devfs_set_flags> functions

- fix problem with SCSI disc compatibility names (sd{a,b,c,d,e,f})
  which assumes ID's start at 0 and increase by 1. Also only create
  devfs entries for SCSI disc partitions which actually exist
  Show new names in partition check
  Thanks to Jakub Jelinek <jj@sunsite.ms.mff.cuni.cz>
===============================================================================
Changes for patch v14

- bug fix in floppy driver: would not compile without
  CONFIG_DEVFS_FS='Y'
  Thanks to Jurgen Botz <jbotz@nova.botz.org>

- bug fix in loop driver
  Thanks to C. Scott Ananian <cananian@alumni.princeton.edu>

- do not create devfs entries for printers not configured
  Thanks to C. Scott Ananian <cananian@alumni.princeton.edu>

- do not create devfs entries for serial ports not present
  Thanks to C. Scott Ananian <cananian@alumni.princeton.edu>

- ensure <tty_register_devfs> is exported from tty_io.c
  Thanks to C. Scott Ananian <cananian@alumni.princeton.edu>

- allow unregistering of devfs symlink entries

- fixed bug in SCSI disc naming introduced in last patch version
===============================================================================
Changes for patch v15

- ported to kernel 2.1.81
===============================================================================
Changes for patch v16

- created <devfs_set_symlink_destination> function

- moved DEVFS_SUPER_MAGIC into header file

- added DEVFS_FL_HIDE flag

- created <devfs_get_maj_min>

- created <devfs_get_handle_from_inode>

- fixed bugs in searching by major&minor

- changed interface to <devfs_unregister>, <devfs_fill_file> and
  <devfs_find_handle>

- fixed inode times when symlink created with symlink(2)

- change tty driver to do auto-creation of devfs entries
  Thanks to C. Scott Ananian <cananian@alumni.princeton.edu>

- fixed bug in genhd.c: whole disc (non-SCSI) was not registered to
  devfs

- updated libc 5.4.43 patch for ttyname()
===============================================================================
Changes for patch v17

- added CONFIG_DEVFS_TTY_COMPAT
  Thanks to C. Scott Ananian <cananian@alumni.princeton.edu>

- bugfix in devfs support for drivers/char/lp.c
  Thanks to C. Scott Ananian <cananian@alumni.princeton.edu>

- clean up serial driver so that PCMCIA devices unregister correctly
  Thanks to C. Scott Ananian <cananian@alumni.princeton.edu>

- fixed bug in genhd.c: whole disc (non-SCSI) was not registered to
  devfs [was missing in patch v16]

- updated libc 5.4.43 patch for ttyname() [was missing in patch v16]

- all SCSI devices now registered in /dev/sg

- support removal of devfs entries via unlink(2)
===============================================================================
Changes for patch v18

- added floppy/?u720 floppy entry

- fixed kerneld support for entries in devfs subdirectories

- incorporated latest patch for ttyname() in libc 5.4.43 from H.J. Lu.
===============================================================================
Changes for patch v19

- bug fix when looking up unregistered entries: kerneld was not called

- fixes for kernel 2.1.86 (now requires 2.1.86)
===============================================================================
Changes for patch v20

- only create available floppy entries
  Thanks to Andrzej Krzysztofowicz <ankry@green.mif.pg.gda.pl>

- new IDE naming scheme following SCSI format (i.e. /dev/id/c0b0t0u0p1
  instead of /dev/hda1)
  Thanks to Andrzej Krzysztofowicz <ankry@green.mif.pg.gda.pl>

- new XT disc naming scheme following SCSI format (i.e. /dev/xd/c0t0p1
  instead of /dev/xda1)
  Thanks to Andrzej Krzysztofowicz <ankry@green.mif.pg.gda.pl>

- new non-standard CD-ROM names (i.e. /dev/sbp/c#t#)
  Thanks to Andrzej Krzysztofowicz <ankry@green.mif.pg.gda.pl>

- allow symlink traversal when mounting the root filesystem

- Create entries for MD devices at MD init
  Thanks to Christophe Leroy <christophe.leroy5@capway.com>
===============================================================================
Changes for patch v21

- ported to kernel 2.1.91
===============================================================================
Changes for patch v22

- SCSI host number patch ("scsihosts=" kernel option)
  Thanks to Andrzej Krzysztofowicz <ankry@green.mif.pg.gda.pl>
===============================================================================
Changes for patch v23

- Fixed persistence bug with device numbers for manually created
  device files

- Fixed problem with recreating symlinks with different content

- Added CONFIG_DEVFS_MOUNT (mount devfs on /dev at boot time)
===============================================================================
Changes for patch v24

- Switched from CONFIG_KERNELD to CONFIG_KMOD: module autoloading
  should now work again

- Hide entries which are manually unlinked

- Always invalidate devfs dentry cache when registering entries

- Support removal of devfs directories via rmdir(2)

- Ensure directories created by <devfs_mk_dir> are visible

- Default no access for "other" for floppy device
===============================================================================
Changes for patch v25

- Updates to CREDITS file and minor IDE numbering change
  Thanks to Andrzej Krzysztofowicz <ankry@green.mif.pg.gda.pl>

- Invalidate devfs dentry cache when making directories

- Invalidate devfs dentry cache when removing entries

- More informative message if root FS mount fails when devfs
  configured

- Fixed persistence bug with fifos
===============================================================================
Changes for patch v26

- ported to kernel 2.1.97

- Changed serial directory from "/dev/serial" to "/dev/tts" and
  "/dev/consoles" to "/dev/vc" to be more friendly to new procps
===============================================================================
Changes for patch v27

- Added support for IDE4 and IDE5
  Thanks to Andrzej Krzysztofowicz <ankry@green.mif.pg.gda.pl>

- Documented "scsihosts=" boot parameter

- Print process command when debugging kerneld/kmod

- Added debugging for register/unregister/change operations

- Added "devfs=" boot options

- Hide unregistered entries by default
===============================================================================
Changes for patch v28

- No longer lock/unlock superblock in <devfs_put_super> (cope with
  recent VFS interface change)

- Do not automatically change ownership/protection of /dev/tty

- Drop negative dentries when they are released

- Manage dcache more efficiently
===============================================================================
Changes for patch v29

- Added DEVFS_FL_AUTO_DEVNUM flag
===============================================================================
Changes for patch v30

- No longer set unnecessary methods

- Ported to kernel 2.1.99-pre3
===============================================================================
Changes for patch v31

- Added PID display to <call_kerneld> debugging message

- Added "diread" and "diwrite" options

- Ported to kernel 2.1.102

- Fixed persistence problem with permissions
===============================================================================
Changes for patch v32

- Fixed devfs support in drivers/block/md.c
===============================================================================
Changes for patch v33

- Support legacy device nodes

- Fixed bug where recreated inodes were hidden

- New IDE naming scheme: everything is under /dev/ide
===============================================================================
Changes for patch v34

- Improved debugging in <get_vfs_inode>

- Prevent duplicate calls to <devfs_mk_dir> in SCSI layer

- No longer free old dentries in <devfs_mk_dir>

- Free all dentries for a given entry when deleting inodes
===============================================================================
Changes for patch v35

- Ported to kernel 2.1.105 (sound driver changes)
===============================================================================
Changes for patch v36

- Fixed sound driver port
===============================================================================
Changes for patch v37

- Minor documentation tweaks
===============================================================================
Changes for patch v38

- More documentation tweaks

- Fix for sound driver port

- Removed ttyname-patch (grab libc 5.4.44 instead)

- Ported to kernel 2.1.107-pre2 (loop driver fix)
===============================================================================
Changes for patch v39

- Ported to kernel 2.1.107 (hd.c hunk broke due to spelling "fixes"). Sigh

- Removed many #ifdef's, replaced with trickery in include/devfs_fs.h
===============================================================================
Changes for patch v40

- Fix for sound driver port

- Limit auto-device numbering to majors 128 to 239
===============================================================================
Changes for patch v41

- Fixed inode times persistence problem
===============================================================================
Changes for patch v42

- Ported to kernel 2.1.108 (drivers/scsi/hosts.c hunk broke)
===============================================================================
Changes for patch v43

- Fixed spelling in <devfs_readlink> debug

- Fixed bug in <devfs_setup> parsing "dilookup"

- More #ifdef's removed

- Supported Sparc keyboard (/dev/kbd)

- Supported DSP56001 digital signal processor (/dev/dsp56k)

- Supported Apple Desktop Bus (/dev/adb)

- Supported Coda network file system (/dev/cfs*)
===============================================================================
Changes for patch v44

- Fixed devfs inode leak when manually recreating inodes

- Fixed permission persistence problem when recreating inodes
===============================================================================
Changes for patch v45

- Ported to kernel 2.1.110
===============================================================================
Changes for patch v46

- Ported to kernel 2.1.112-pre1

- Removed harmless "unused variable" compiler warning

- Fixed modes for manually recreated device nodes
===============================================================================
Changes for patch v47

- Added NULL devfs inode warning in <devfs_read_inode>

- Force all inode nlink values to 1
===============================================================================
Changes for patch v48

- Added "dimknod" option

- Set inode nlink to 0 when freeing dentries

- Added support for virtual console capture devices (/dev/vcs*)
  Thanks to Dennis Hou <smilax@mindmeld.yi.org>

- Fixed modes for manually recreated symlinks
===============================================================================
Changes for patch v49

- Ported to kernel 2.1.113
===============================================================================
Changes for patch v50

- Fixed bugs in recreated directories and symlinks
===============================================================================
Changes for patch v51

- Improved robustness of rc.devfs script
  Thanks to Roderich Schupp <rsch@experteam.de>

- Fixed bugs in recreated device nodes

- Fixed bug in currently unused <devfs_get_handle_from_inode>

- Defined new <devfs_handle_t> type

- Improved debugging when getting entries

- Fixed bug where directories could be emptied

- Ported to kernel 2.1.115
===============================================================================
Changes for patch v52

- Replaced dummy .epoch inode with .devfsd character device

- Modified rc.devfs to take account of above change

- Removed spurious driver warning messages when CONFIG_DEVFS_FS=n

- Implemented devfsd protocol revision 0
===============================================================================
Changes for patch v53

- Ported to kernel 2.1.116 (kmod change broke hunk)

- Updated Documentation/Configure.help

- Test and tty pattern patch for rc.devfs script
  Thanks to Roderich Schupp <rsch@experteam.de>

- Added soothing message to warning in <devfs_d_iput>
===============================================================================
Changes for patch v54

- Ported to kernel 2.1.117

- Fixed default permissions in sound driver

- Added support for frame buffer devices (/dev/fb*)
===============================================================================
Changes for patch v55

- Ported to kernel 2.1.119

- Use GCC extensions for structure initialisations

- Implemented async open notification

- Incremented devfsd protocol revision to 1
===============================================================================
Changes for patch v56

- Ported to kernel 2.1.120-pre3

- Moved async open notification to end of <devfs_open>
===============================================================================
Changes for patch v57

- Ported to kernel 2.1.121

- Prepended "/dev/" to module load request

- Renamed <call_kerneld> to <call_kmod>

- Created sample modules.conf file
===============================================================================
Changes for patch v58

- Fixed typo "AYSNC" -> "ASYNC"
===============================================================================
Changes for patch v59

- Added open flag for files
===============================================================================
Changes for patch v60

- Ported to kernel 2.1.123-pre2
===============================================================================
Changes for patch v61

- Set i_blocks=0 and i_blksize=1024 in <devfs_read_inode>
===============================================================================
Changes for patch v62

- Ported to kernel 2.1.123
===============================================================================
Changes for patch v63

- Ported to kernel 2.1.124-pre2
===============================================================================
Changes for patch v64

- Fixed Unix98 pty support

- Increased buffer size in <get_partition_list> to avoid crash and
  burn
===============================================================================
Changes for patch v65

- More Unix98 pty support fixes

- Added test for empty <<name>> in <devfs_find_handle>

- Renamed <generate_path> to <devfs_generate_path> and published

- Created /dev/root symlink
  Thanks to Roderich Schupp <rsch@ExperTeam.de>
  with further modifications by me
===============================================================================
Changes for patch v66

- Yet more Unix98 pty support fixes (now tested)

- Created <devfs_get_fops>

- Support media change checks when CONFIG_DEVFS_ONLY=y

- Abolished Unix98-style PTY names for old PTY devices
===============================================================================
Changes for patch v67

- Added inline declaration for dummy <devfs_generate_path>

- Removed spurious "unable to register... in devfs" messages when
  CONFIG_DEVFS_FS=n

- Fixed misc. devices when CONFIG_DEVFS_FS=n

- Limit auto-device numbering to majors 144 to 239
===============================================================================
Changes for patch v68

- Hide unopened virtual consoles from directory listings

- Added support for video capture devices

- Ported to kernel 2.1.125
===============================================================================
Changes for patch v69

- Fix for CONFIG_VT=n
===============================================================================
Changes for patch v70

- Added support for non-OSS/Free sound cards
===============================================================================
Changes for patch v71

- Ported to kernel 2.1.126-pre2
===============================================================================
Changes for patch v72

- #ifdef's for CONFIG_DEVFS_DISABLE_OLD_NAMES removed
===============================================================================
Changes for patch v73

- CONFIG_DEVFS_DISABLE_OLD_NAMES replaced with "nocompat" boot option

- CONFIG_DEVFS_BOOT_OPTIONS removed: boot options always available
===============================================================================
Changes for patch v74

- Removed CONFIG_DEVFS_MOUNT and "mount" boot option and replaced with
  "nomount" boot option

- Documentation updates

- Updated sample modules.conf
===============================================================================
Changes for patch v75

- Updated sample modules.conf

- Remount devfs after initrd finishes

- Ported to kernel 2.1.127

- Added support for ISDN
  Thanks to Christophe Leroy <christophe.leroy5@capway.com>
===============================================================================
Changes for patch v76

- Updated an email address in ChangeLog

- CONFIG_DEVFS_ONLY replaced with "only" boot option
===============================================================================
Changes for patch v77

- Added DEVFS_FL_REMOVABLE flag

- Check for disc change when listing directories with removable media
  devices

- Use DEVFS_FL_REMOVABLE in sd.c

- Ported to kernel 2.1.128
===============================================================================
Changes for patch v78

- Only call <scan_dir_for_removable> on first call to <devfs_readdir>

- Ported to kernel 2.1.129-pre5

- ISDN support improvements
  Thanks to Christophe Leroy <christophe.leroy5@capway.com>
===============================================================================
Changes for patch v79

- Ported to kernel 2.1.130

- Renamed miscdevice "apm" to "apm_bios" to be consistent with
  devices.txt
===============================================================================
Changes for patch v80

- Ported to kernel 2.1.131

- Updated <devfs_rmdir> for VFS change in 2.1.131
===============================================================================
Changes for patch v81

- Fixed permissions on /dev/ptmx
===============================================================================
Changes for patch v82

- Ported to kernel 2.1.132-pre4

- Changed initial permissions on /dev/pts/*

- Created <devfs_mk_compat>

- Added "symlinks" boot option

- Changed devfs_register_blkdev() back to register_blkdev() for IDE

- Check for partitions on removable media in <devfs_lookup>
===============================================================================
Changes for patch v83

- Fixed support for ramdisc when using string-based root FS name

- Ported to kernel 2.2.0-pre1
===============================================================================
Changes for patch v84

- Ported to kernel 2.2.0-pre7
===============================================================================
Changes for patch v85

- Compile fixes for driver/sound/sound_common.c (non-module) and
  drivers/isdn/isdn_common.c
  Thanks to Christophe Leroy <christophe.leroy5@capway.com>

- Added support for registering regular files

- Created <devfs_set_file_size>

- Added /dev/cpu/mtrr as an alternative interface to /proc/mtrr

- Update devfs inodes from entries if not changed through FS
===============================================================================
Changes for patch v86

- Ported to kernel 2.2.0-pre9
===============================================================================
Changes for patch v87

- Fixed bug when mounting non-devfs devices in a devfs
===============================================================================
Changes for patch v88

- Fixed <devfs_fill_file> to only initialise temporary inodes

- Trap for NULL fops in <devfs_register>

- Return -ENODEV in <devfs_fill_file> for non-driver inodes

- Fixed bug when unswapping non-devfs devices in a devfs
===============================================================================
Changes for patch v89

- Switched to C data types in include/linux/devfs_fs.h

- Switched from PATH_MAX to DEVFS_PATHLEN

- Updated Documentation/filesystems/devfs/modules.conf to take account
  of reverse scanning (!) by modprobe

- Ported to kernel 2.2.0
===============================================================================
Changes for patch v90

- CONFIG_DEVFS_DISABLE_OLD_TTY_NAMES replaced with "nottycompat" boot
  option

- CONFIG_DEVFS_TTY_COMPAT removed: existing "symlinks" boot option now
  controls this. This means you must have libc 5.4.44 or later, or a
  recent version of libc 6 if you use the "symlinks" option
===============================================================================
Changes for patch v91

- Switch from <devfs_mk_symlink> to <devfs_mk_compat> in
  drivers/char/vc_screen.c to fix problems with Midnight Commander
===============================================================================
Changes for patch v92

- Ported to kernel 2.2.2-pre5
===============================================================================
Changes for patch v93

- Modified <sd_name> in drivers/scsi/sd.c to cope with devices that
  don't exist (which happens with new RAID autostart code printk()s)
===============================================================================
Changes for patch v94

- Fixed bug in joystick driver: only first joystick was registered
===============================================================================
Changes for patch v95

- Fixed another bug in joystick driver

- Fixed <devfsd_read> to not overrun event buffer
===============================================================================
Changes for patch v96

- Ported to kernel 2.2.5-2

- Created <devfs_auto_unregister>

- Fixed bugs: compatibility entries were not unregistered for:
    loop driver
    floppy driver
    RAMDISC driver
    IDE tape driver
    SCSI CD-ROM driver
    SCSI HDD driver
===============================================================================
Changes for patch v97

- Fixed bugs: compatibility entries were not unregistered for:
    ALSA sound driver
    partitions in generic disc driver

- Don't return unregistred entries in <devfs_find_handle>

- Panic in <devfs_unregister> if entry unregistered

- Don't panic in <devfs_auto_unregister> for duplicates
===============================================================================
Changes for patch v98

- Don't unregister already unregistered entries in <unregister>

- Register entry in <sd_detect>

- Unregister entry in <sd_detach>

- Changed to <devfs_*register_chrdev> in drivers/char/tty_io.c

- Ported to kernel 2.2.7
===============================================================================
Changes for patch v99

- Ported to kernel 2.2.8

- Fixed bug in drivers/scsi/sd.c when >16 SCSI discs

- Disable warning messages when unable to read partition table for
  removable media
===============================================================================
Changes for patch v100

- Ported to kernel 2.3.1-pre5

- Added "oops-on-panic" boot option

- Improved debugging in <devfs_register> and <devfs_unregister>

- Register entry in <sr_detect>

- Unregister entry in <sr_detach>

- Register entry in <sg_detect>

- Unregister entry in <sg_detach>

- Added support for ALSA drivers
===============================================================================
Changes for patch v101

- Ported to kernel 2.3.2
===============================================================================
Changes for patch v102

- Update serial driver to register PCMCIA entries
  Thanks to Roch-Alexandre Nomine-Beguin <roch@samarkand.infini.fr>

- Updated an email address in ChangeLog

- Hide virtual console capture entries from directory listings when
  corresponding console device is not open
===============================================================================
Changes for patch v103

- Ported to kernel 2.3.3
===============================================================================
Changes for patch v104

- Added documentation for some functions

- Added "doc" target to fs/devfs/Makefile

- Added "v4l" directory for video4linux devices

- Replaced call to <devfs_unregister> in <sd_detach> with call to
  <devfs_register_partitions>

- Moved registration for sr and sg drivers from detect() to attach()
  methods

- Register entries in <st_attach> and unregister in <st_detach>

- Work around IDE driver treating CD-ROM as gendisk

- Use <sed> instead of <tr> in rc.devfs

- Updated ToDo list

- Removed "oops-on-panic" boot option: now always Oops
===============================================================================
Changes for patch v105

- Unregister SCSI host from <scsi_host_no_list> in <scsi_unregister>
  Thanks to Zoltn Bszrmnyi <zboszor@mail.externet.hu>

- Don't save /dev/log in rc.devfs

- Ported to kernel 2.3.4-pre1
===============================================================================
Changes for patch v106

- Fixed silly typo in drivers/scsi/st.c

- Improved debugging in <devfs_register>
===============================================================================
Changes for patch v107

- Added "diunlink" and "nokmod" boot options

- Removed superfluous warning message in <devfs_d_iput>
===============================================================================
Changes for patch v108

- Remove entries when unloading sound module
===============================================================================
Changes for patch v109

- Ported to kernel 2.3.6-pre2
===============================================================================
Changes for patch v110

- Took account of change to <d_alloc_root>
===============================================================================
Changes for patch v111

- Created separate event queue for each mounted devfs

- Removed <devfs_invalidate_dcache>

- Created new ioctl()s for devfsd

- Incremented devfsd protocol revision to 3

- Fixed bug when re-creating directories: contents were lost

- Block access to inodes until devfsd updates permissions
===============================================================================
Changes for patch v112

- Modified patch so it applies against 2.3.5 and 2.3.6

- Updated an email address in ChangeLog

- Do not automatically change ownership/protection of /dev/tty<n>

- Updated sample modules.conf

- Switched to sending process uid/gid to devfsd

- Renamed <call_kmod> to <try_modload>

- Added DEVFSD_NOTIFY_LOOKUP event

- Added DEVFSD_NOTIFY_CHANGE event

- Added DEVFSD_NOTIFY_CREATE event

- Incremented devfsd protocol revision to 4

- Moved kernel-specific stuff to include/linux/devfs_fs_kernel.h
===============================================================================
Changes for patch v113

- Ported to kernel 2.3.9

- Restricted permissions on some block devices
===============================================================================
Changes for patch v114

- Added support for /dev/netlink
  Thanks to Dennis Hou <smilax@mindmeld.yi.org>

- Return EISDIR rather than EINVAL for read(2) on directories

- Ported to kernel 2.3.10
===============================================================================
Changes for patch v115

- Added support for all remaining character devices
  Thanks to Dennis Hou <smilax@mindmeld.yi.org>

- Cleaned up netlink support
===============================================================================
Changes for patch v116

- Added support for /dev/parport%d
  Thanks to Tim Waugh <tim@cyberelk.demon.co.uk>

- Fixed parallel port ATAPI tape driver

- Fixed Atari SLM laser printer driver
===============================================================================
Changes for patch v117

- Added support for COSA card
  Thanks to Dennis Hou <smilax@mindmeld.yi.org>

- Fixed drivers/char/ppdev.c: missing #include <linux/init.h>

- Fixed drivers/char/ftape/zftape/zftape-init.c
  Thanks to Vladimir Popov <mashgrad@usa.net>
===============================================================================
Changes for patch v118

- Ported to kernel 2.3.15-pre3

- Fixed bug in loop driver

- Unregister /dev/lp%d entries in drivers/char/lp.c
  Thanks to Maciej W. Rozycki <macro@ds2.pg.gda.pl>
===============================================================================
Changes for patch v119

- Ported to kernel 2.3.16
===============================================================================
Changes for patch v120

- Fixed bug in drivers/scsi/scsi.c

- Added /dev/ppp
  Thanks to Dennis Hou <smilax@mindmeld.yi.org>

- Ported to kernel 2.3.17
===============================================================================
Changes for patch v121

- Fixed bug in drivers/block/loop.c

- Ported to kernel 2.3.18
===============================================================================
Changes for patch v122

- Ported to kernel 2.3.19
===============================================================================
Changes for patch v123

- Ported to kernel 2.3.20
===============================================================================
Changes for patch v124

- Ported to kernel 2.3.21
===============================================================================
Changes for patch v125

- Created <devfs_get_info>, <devfs_set_info>,
  <devfs_get_first_child> and <devfs_get_next_sibling>
  Added <<dir>> parameter to <devfs_register>, <devfs_mk_compat>,
  <devfs_mk_dir> and <devfs_find_handle>
  Work sponsored by SGI

- Fixed apparent bug in COSA driver

- Re-instated "scsihosts=" boot option
===============================================================================
Changes for patch v126

- Always create /dev/pts if CONFIG_UNIX98_PTYS=y

- Fixed call to <devfs_mk_dir> in drivers/block/ide-disk.c
  Thanks to Dennis Hou <smilax@mindmeld.yi.org>

- Allow multiple unregistrations

- Created /dev/scsi hierarchy
  Work sponsored by SGI
===============================================================================
Changes for patch v127

Work sponsored by SGI

- No longer disable devpts if devfs enabled (caveat emptor)

- Added flags array to struct gendisk and removed code from
  drivers/scsi/sd.c

- Created /dev/discs hierarchy
===============================================================================
Changes for patch v128

Work sponsored by SGI

- Created /dev/cdroms hierarchy
===============================================================================
Changes for patch v129

Work sponsored by SGI

- Removed compatibility entries for sound devices

- Removed compatibility entries for printer devices

- Removed compatibility entries for video4linux devices

- Removed compatibility entries for parallel port devices

- Removed compatibility entries for frame buffer devices
===============================================================================
Changes for patch v130

Work sponsored by SGI

- Added major and minor number to devfsd protocol

- Incremented devfsd protocol revision to 5

- Removed compatibility entries for SoundBlaster CD-ROMs

- Removed compatibility entries for netlink devices

- Removed compatibility entries for SCSI generic devices

- Removed compatibility entries for SCSI tape devices
===============================================================================
Changes for patch v131

Work sponsored by SGI

- Support info pointer for all devfs entry types

- Added <<info>> parameter to <devfs_mk_dir> and <devfs_mk_symlink>

- Removed /dev/st hierarchy

- Removed /dev/sg hierarchy

- Removed compatibility entries for loop devices

- Removed compatibility entries for IDE tape devices

- Removed compatibility entries for SCSI CD-ROMs

- Removed /dev/sr hierarchy
===============================================================================
Changes for patch v132

Work sponsored by SGI

- Removed compatibility entries for floppy devices

- Removed compatibility entries for RAMDISCs

- Removed compatibility entries for meta-devices

- Removed compatibility entries for SCSI discs

- Created <devfs_make_root>

- Removed /dev/sd hierarchy

- Support "../" when searching devfs namespace

- Created /dev/ide/host* hierarchy

- Supported IDE hard discs in /dev/ide/host* hierarchy

- Removed compatibility entries for IDE discs

- Removed /dev/ide/hd hierarchy

- Supported IDE CD-ROMs in /dev/ide/host* hierarchy

- Removed compatibility entries for IDE CD-ROMs

- Removed /dev/ide/cd hierarchy
===============================================================================
Changes for patch v133

Work sponsored by SGI

- Created <devfs_get_unregister_slave>

- Fixed bug in fs/partitions/check.c when rescanning
===============================================================================
Changes for patch v134

Work sponsored by SGI

- Removed /dev/sd, /dev/sr, /dev/st and /dev/sg directories

- Removed /dev/ide/hd directory

- Exported <devfs_get_parent>

- Created <devfs_register_tape> and /dev/tapes hierarchy

- Removed /dev/ide/mt hierarchy

- Removed /dev/ide/fd hierarchy

- Ported to kernel 2.3.25
===============================================================================
Changes for patch v135

Work sponsored by SGI

- Removed compatibility entries for virtual console capture devices

- Removed unused <devfs_set_symlink_destination>

- Removed compatibility entries for serial devices

- Removed compatibility entries for console devices

- Do not hide entries from devfsd or children

- Removed DEVFS_FL_TTY_COMPAT flag

- Removed "nottycompat" boot option

- Removed <devfs_mk_compat>
===============================================================================
Changes for patch v136

Work sponsored by SGI

- Moved BSD pty devices to /dev/pty

- Added DEVFS_FL_WAIT flag
===============================================================================
Changes for patch v137

Work sponsored by SGI

- Really fixed bug in fs/partitions/check.c when rescanning

- Support new "disc" naming scheme in <get_removable_partition>

- Allow NULL fops in <devfs_register>

- Removed redundant name functions in SCSI disc and IDE drivers
===============================================================================
Changes for patch v138

Work sponsored by SGI

- Fixed old bugs in drivers/block/paride/pt.c, drivers/char/tpqic02.c,
  drivers/net/wan/cosa.c and drivers/scsi/scsi.c
  Thanks to Sergey Kubushin <ksi@ksi-linux.com>

- Fall back to major table if NULL fops given to <devfs_register>
===============================================================================
Changes for patch v139

Work sponsored by SGI

- Corrected and moved <get_blkfops> and <get_chrfops> declarations
  from arch/alpha/kernel/osf_sys.c to include/linux/fs.h

- Removed name function from struct gendisk

- Updated devfs FAQ
===============================================================================
Changes for patch v140

Work sponsored by SGI

- Ported to kernel 2.3.27
===============================================================================
Changes for patch v141

Work sponsored by SGI

- Bug fix in arch/m68k/atari/joystick.c

- Moved ISDN and capi devices to /dev/isdn
===============================================================================
Changes for patch v142

Work sponsored by SGI

- Bug fix in drivers/block/ide-probe.c (patch confusion)
===============================================================================
Changes for patch v143

Work sponsored by SGI

- Bug fix in drivers/block/blkpg.c:partition_name()
===============================================================================
Changes for patch v144

Work sponsored by SGI

- Ported to kernel 2.3.29

- Removed calls to <devfs_register> from cdu31a, cm206, mcd and mcdx
  CD-ROM drivers: generic driver handles this now

- Moved joystick devices to /dev/joysticks
===============================================================================
Changes for patch v145

Work sponsored by SGI

- Ported to kernel 2.3.30-pre3

- Register whole-disc entry even for invalid partition tables

- Fixed bug in mounting root FS when initrd enabled

- Fixed device entry leak with IDE CD-ROMs

- Fixed compile problem with drivers/isdn/isdn_common.c

- Moved COSA devices to /dev/cosa

- Support fifos when unregistering

- Created <devfs_register_series> and used in many drivers

- Moved Coda devices to /dev/coda

- Moved parallel port IDE tapes to /dev/pt

- Moved parallel port IDE generic devices to /dev/pg
===============================================================================
Changes for patch v146

Work sponsored by SGI

- Removed obsolete DEVFS_FL_COMPAT and DEVFS_FL_TOLERANT flags

- Fixed compile problem with fs/coda/psdev.c

- Reinstate change to <devfs_register_blkdev> in
  drivers/block/ide-probe.c now that fs/isofs/inode.c is fixed

- Switched to <devfs_register_blkdev> in drivers/block/floppy.c,
  drivers/scsi/sr.c and drivers/block/md.c

- Moved DAC960 devices to /dev/dac960
===============================================================================
Changes for patch v147

Work sponsored by SGI

- Ported to kernel 2.3.32-pre4
===============================================================================
Changes for patch v148

Work sponsored by SGI

- Removed kmod support: use devfsd instead

- Moved miscellaneous character devices to /dev/misc
===============================================================================
Changes for patch v149

Work sponsored by SGI

- Ensure include/linux/joystick.h is OK for user-space

- Improved debugging in <get_vfs_inode>

- Ensure dentries created by devfsd will be cleaned up
===============================================================================
Changes for patch v150

Work sponsored by SGI

- Ported to kernel 2.3.34
===============================================================================
Changes for patch v151

Work sponsored by SGI

- Ported to kernel 2.3.35-pre1

- Created <devfs_get_name>
===============================================================================
Changes for patch v152

Work sponsored by SGI

- Updated sample modules.conf

- Ported to kernel 2.3.36-pre1
===============================================================================
Changes for patch v153

Work sponsored by SGI

- Ported to kernel 2.3.42

- Removed <devfs_fill_file>
===============================================================================
Changes for patch v154

Work sponsored by SGI

- Took account of device number changes for /dev/fb*
===============================================================================
Changes for patch v155

Work sponsored by SGI

- Ported to kernel 2.3.43-pre8

- Moved /dev/tty0 to /dev/vc/0

- Moved sequence number formatting from <_tty_make_name> to drivers
===============================================================================
Changes for patch v156

Work sponsored by SGI

- Fixed breakage in drivers/scsi/sd.c due to recent SCSI changes
===============================================================================
Changes for patch v157

Work sponsored by SGI

- Ported to kernel 2.3.45
===============================================================================
Changes for patch v158

Work sponsored by SGI

- Ported to kernel 2.3.46-pre2
===============================================================================
Changes for patch v159

Work sponsored by SGI

- Fixed drivers/block/md.c
  Thanks to Mike Galbraith <mikeg@weiden.de>

- Documentation fixes

- Moved device registration from <lp_init> to <lp_register>
  Thanks to Tim Waugh <twaugh@redhat.com>
===============================================================================
Changes for patch v160

Work sponsored by SGI

- Fixed drivers/char/joystick/joystick.c
  Thanks to Vojtech Pavlik <vojtech@suse.cz>

- Documentation updates

- Fixed arch/i386/kernel/mtrr.c if procfs and devfs not enabled

- Fixed drivers/char/stallion.c
===============================================================================
Changes for patch v161

Work sponsored by SGI

- Remove /dev/ide when ide-mod is unloaded

- Fixed bug in drivers/block/ide-probe.c when secondary but no primary

- Added DEVFS_FL_NO_PERSISTENCE flag

- Used new DEVFS_FL_NO_PERSISTENCE flag for Unix98 pty slaves

- Removed unnecessary call to <update_devfs_inode_from_entry> in
  <devfs_readdir>

- Only set auto-ownership for /dev/pty/s*
===============================================================================
Changes for patch v162

Work sponsored by SGI

- Set inode->i_size to correct size for symlinks
  Thanks to Jeremy Fitzhardinge <jeremy@goop.org>

- Only give lookup() method to directories to comply with new VFS
  assumptions

- Remove unnecessary tests in symlink methods

- Don't kill existing block ops in <devfs_read_inode>

- Restore auto-ownership for /dev/pty/m*
===============================================================================
Changes for patch v163

Work sponsored by SGI

- Don't create missing directories in <devfs_find_handle>

- Removed Documentation/filesystems/devfs/mk-devlinks

- Updated Documentation/filesystems/devfs/README
===============================================================================
Changes for patch v164

Work sponsored by SGI

- Fixed CONFIG_DEVFS breakage in drivers/char/serial.c introduced in
  linux-2.3.99-pre6-7
===============================================================================
Changes for patch v165

Work sponsored by SGI

- Ported to kernel 2.3.99-pre6
===============================================================================
Changes for patch v166

Work sponsored by SGI

- Added CONFIG_DEVFS_MOUNT
===============================================================================
Changes for patch v167

Work sponsored by SGI

- Updated Documentation/filesystems/devfs/README

- Updated sample modules.conf
===============================================================================
Changes for patch v168

Work sponsored by SGI

- Disabled multi-mount capability (use VFS bindings instead)

- Updated README from master HTML file
===============================================================================
Changes for patch v169

Work sponsored by SGI

- Removed multi-mount code

- Removed compatibility macros: VFS has changed too much
===============================================================================
Changes for patch v170

Work sponsored by SGI

- Updated README from master HTML file

- Merged devfs inode into devfs entry
===============================================================================
Changes for patch v171

Work sponsored by SGI

- Updated sample modules.conf

- Removed dead code in <devfs_register> which used to call
  <free_dentries>

- Ported to kernel 2.4.0-test2-pre3
===============================================================================
Changes for patch v172

Work sponsored by SGI

- Changed interface to <devfs_register>

- Changed interface to <devfs_register_series>
===============================================================================
Changes for patch v173

Work sponsored by SGI

- Simplified interface to <devfs_mk_symlink>

- Simplified interface to <devfs_mk_dir>

- Simplified interface to <devfs_find_handle>
===============================================================================
Changes for patch v174

Work sponsored by SGI

- Updated README from master HTML file
===============================================================================
Changes for patch v175

Work sponsored by SGI

- DocBook update for fs/devfs/base.c
  Thanks to Tim Waugh <twaugh@redhat.com>

- Removed stale fs/tunnel.c (was never used or completed)
===============================================================================
Changes for patch v176

Work sponsored by SGI

- Updated ToDo list

- Removed sample modules.conf: now distributed with devfsd

- Updated README from master HTML file

- Ported to kernel 2.4.0-test3-pre4 (which had devfs-patch-v174)
===============================================================================
Changes for patch v177

- Updated README from master HTML file

- Documentation cleanups

- Ensure <devfs_generate_path> terminates string for root entry
  Thanks to Tim Jansen <tim@tjansen.de>

- Exported <devfs_get_name> to modules

- Make <devfs_mk_symlink> send events to devfsd

- Cleaned up option processing in <devfs_setup>

- Fixed bugs in handling symlinks: could leak or cause Oops

- Cleaned up directory handling by separating fops
  Thanks to Alexander Viro <viro@parcelfarce.linux.theplanet.co.uk>
===============================================================================
Changes for patch v178

- Fixed handling of inverted options in <devfs_setup>
===============================================================================
Changes for patch v179

- Adjusted <try_modload> to account for <devfs_generate_path> fix
===============================================================================
Changes for patch v180

- Fixed !CONFIG_DEVFS_FS stub declaration of <devfs_get_info>
===============================================================================
Changes for patch v181

- Answered question posed by Al Viro and removed his comments from <devfs_open>

- Moved setting of registered flag after other fields are changed

- Fixed race between <devfsd_close> and <devfsd_notify_one>

- Global VFS changes added bogus BKL to devfsd_close(): removed

- Widened locking in <devfs_readlink> and <devfs_follow_link>

- Replaced <devfsd_read> stack usage with <devfsd_ioctl> kmalloc

- Simplified locking in <devfsd_ioctl> and fixed memory leak
===============================================================================
Changes for patch v182

- Created <devfs_*alloc_major> and <devfs_*alloc_devnum>

- Removed broken devnum allocation and use <devfs_alloc_devnum>

- Fixed old devnum leak by calling new <devfs_dealloc_devnum>

- Created <devfs_*alloc_unique_number>

- Fixed number leak for /dev/cdroms/cdrom%d

- Fixed number leak for /dev/discs/disc%d
===============================================================================
Changes for patch v183

- Fixed bug in <devfs_setup> which could hang boot process
===============================================================================
Changes for patch v184

- Documentation typo fix for fs/devfs/util.c

- Fixed drivers/char/stallion.c for devfs

- Added DEVFSD_NOTIFY_DELETE event

- Updated README from master HTML file

- Removed #include <asm/segment.h> from fs/devfs/base.c
===============================================================================
Changes for patch v185

- Made <block_semaphore> and <char_semaphore> in fs/devfs/util.c
  private

- Fixed inode table races by removing it and using inode->u.generic_ip
  instead

- Moved <devfs_read_inode> into <get_vfs_inode>

- Moved <devfs_write_inode> into <devfs_notify_change>
===============================================================================
Changes for patch v186

- Fixed race in <devfs_do_symlink> for uni-processor

- Updated README from master HTML file
===============================================================================
Changes for patch v187

- Fixed drivers/char/stallion.c for devfs

- Fixed drivers/char/rocket.c for devfs

- Fixed bug in <devfs_alloc_unique_number>: limited to 128 numbers
===============================================================================
Changes for patch v188

- Updated major masks in fs/devfs/util.c up to Linus' "no new majors"
  proclamation. Block: were 126 now 122 free, char: were 26 now 19 free

- Updated README from master HTML file

- Removed remnant of multi-mount support in <devfs_mknod>

- Removed unused DEVFS_FL_SHOW_UNREG flag
===============================================================================
Changes for patch v189

- Removed nlink field from struct devfs_inode

- Removed auto-ownership for /dev/pty/* (BSD ptys) and used
  DEVFS_FL_CURRENT_OWNER|DEVFS_FL_NO_PERSISTENCE for /dev/pty/s* (just
  like Unix98 pty slaves) and made /dev/pty/m* rw-rw-rw- access
===============================================================================
Changes for patch v190

- Updated README from master HTML file

- Replaced BKL with global rwsem to protect symlink data (quick and
  dirty hack)
===============================================================================
Changes for patch v191

- Replaced global rwsem for symlink with per-link refcount
===============================================================================
Changes for patch v192

- Removed unnecessary #ifdef CONFIG_DEVFS_FS from arch/i386/kernel/mtrr.c

- Ported to kernel 2.4.10-pre11

- Set inode->i_mapping->a_ops for block nodes in <get_vfs_inode>
===============================================================================
Changes for patch v193

- Went back to global rwsem for symlinks (refcount scheme no good)
===============================================================================
Changes for patch v194

- Fixed overrun in <devfs_link> by removing function (not needed)

- Updated README from master HTML file
===============================================================================
Changes for patch v195

- Fixed buffer underrun in <try_modload>

- Moved down_read() from <search_for_entry_in_dir> to <find_entry>
===============================================================================
Changes for patch v196

- Fixed race in <devfsd_ioctl> when setting event mask
  Thanks to Kari Hurtta <hurtta@leija.mh.fmi.fi>

- Avoid deadlock in <devfs_follow_link> by using temporary buffer
===============================================================================
Changes for patch v197

- First release of new locking code for devfs core (v1.0)

- Fixed bug in drivers/cdrom/cdrom.c
===============================================================================
Changes for patch v198

- Discard temporary buffer, now use "%s" for dentry names

- Don't generate path in <try_modload>: use fake entry instead

- Use "existing" directory in <_devfs_make_parent_for_leaf>

- Use slab cache rather than fixed buffer for devfsd events
===============================================================================
Changes for patch v199

- Removed obsolete usage of DEVFS_FL_NO_PERSISTENCE

- Send DEVFSD_NOTIFY_REGISTERED events in <devfs_mk_dir>

- Fixed locking bug in <devfs_d_revalidate_wait> due to typo

- Do not send CREATE, CHANGE, ASYNC_OPEN or DELETE events from devfsd
  or children
===============================================================================
Changes for patch v200

- Ported to kernel 2.5.1-pre2
===============================================================================
Changes for patch v201

- Fixed bug in <devfsd_read>: was dereferencing freed pointer
===============================================================================
Changes for patch v202

- Fixed bug in <devfsd_close>: was dereferencing freed pointer

- Added process group check for devfsd privileges
===============================================================================
Changes for patch v203

- Use SLAB_ATOMIC in <devfsd_notify_de> from <devfs_d_delete>
===============================================================================
Changes for patch v204

- Removed long obsolete rc.devfs

- Return old entry in <devfs_mk_dir> for 2.4.x kernels

- Updated README from master HTML file

- Increment refcount on module in <check_disc_changed>

- Created <devfs_get_handle> and exported <devfs_put>

- Increment refcount on module in <devfs_get_ops>

- Created <devfs_put_ops> and used where needed to fix races

- Added clarifying comments in response to preliminary EMC code review

- Added poisoning to <devfs_put>

- Improved debugging messages

- Fixed unregister bugs in drivers/md/lvm-fs.c
===============================================================================
Changes for patch v205

- Corrected (made useful) debugging message in <unregister>

- Moved <kmem_cache_create> in <mount_devfs_fs> to <init_devfs_fs>

- Fixed drivers/md/lvm-fs.c to create "lvm" entry

- Added magic number to guard against scribbling drivers

- Only return old entry in <devfs_mk_dir> if a directory

- Defined macros for error and debug messages

- Updated README from master HTML file
===============================================================================
Changes for patch v206

- Added support for multiple Compaq cpqarray controllers

- Fixed (rare, old) race in <devfs_lookup>
===============================================================================
Changes for patch v207

- Fixed deadlock bug in <devfs_d_revalidate_wait>

- Tag VFS deletable in <devfs_mk_symlink> if handle ignored

- Updated README from master HTML file
===============================================================================
Changes for patch v208

- Added KERN_* to remaining messages

- Cleaned up declaration of <stat_read>

- Updated README from master HTML file
===============================================================================
Changes for patch v209

- Updated README from master HTML file

- Removed silently introduced calls to lock_kernel() and
  unlock_kernel() due to recent VFS locking changes. BKL isn't
  required in devfs 

- Changed <devfs_rmdir> to allow later additions if not yet empty

- Added calls to <devfs_register_partitions> in drivers/block/blkpc.c
  <add_partition> and <del_partition>

- Fixed bug in <devfs_alloc_unique_number>: was clearing beyond
  bitfield

- Fixed bitfield data type for <devfs_*alloc_devnum>

- Made major bitfield type and initialiser 64 bit safe
===============================================================================
Changes for patch v210

- Updated fs/devfs/util.c to fix shift warning on 64 bit machines
  Thanks to Anton Blanchard <anton@samba.org>

- Updated README from master HTML file
===============================================================================
Changes for patch v211

- Do not put miscellaneous character devices in /dev/misc if they
  specify their own directory (i.e. contain a '/' character)

- Copied macro for error messages from fs/devfs/base.c to
  fs/devfs/util.c and made use of this macro

- Removed 2.4.x compatibility code from fs/devfs/base.c
===============================================================================
Changes for patch v212

- Added BKL to <devfs_open> because drivers still need it
===============================================================================
Changes for patch v213

- Protected <scan_dir_for_removable> and <get_removable_partition>
  from changing directory contents
===============================================================================
Changes for patch v214

- Switched to ISO C structure field initialisers

- Switch to set_current_state() and move before add_wait_queue()

- Updated README from master HTML file

- Fixed devfs entry leak in <devfs_readdir> when *readdir fails
===============================================================================
Changes for patch v215

- Created <devfs_find_and_unregister>

- Switched many functions from <devfs_find_handle> to
  <devfs_find_and_unregister>

- Switched many functions from <devfs_find_handle> to <devfs_get_handle>
===============================================================================
Changes for patch v216

- Switched arch/ia64/sn/io/hcl.c from <devfs_find_handle> to
  <devfs_get_handle>

- Removed deprecated <devfs_find_handle>
===============================================================================
Changes for patch v217

- Exported <devfs_find_and_unregister> and <devfs_only> to modules

- Updated README from master HTML file

- Fixed module unload race in <devfs_open>
===============================================================================
Changes for patch v218

- Removed DEVFS_FL_AUTO_OWNER flag

- Switched lingering structure field initialiser to ISO C

- Added locking when setting/clearing flags

- Documentation fix in fs/devfs/util.c