* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/gerg/m68knommu: (25 commits)
m68knommu: fix broken setting of irq_chip and handler
m68knommu: switch to using -mcpu= flags for ColdFire targets
m68knommu: arch/m68knommu/Kconfig whitespace cleanup
m68knommu: create optimal separate instruction and data cache for ColdFire
m68knommu: support ColdFire caches that do copyback and write-through
m68knommu: support version 2 ColdFire split cache
m68knommu: make cache push code ColdFire generic
m68knommu: clean up ColdFire cache control code
m68knommu: move inclusion of ColdFire v4 cache registers
m68knommu: merge bit definitions for version 3 ColdFire cache controller
m68knommu: create bit definitions for the version 2 ColdFire cache controller
m68knommu: remove empty __iounmap() it is no used
m68knommu: remove kernel_map() code, it is not used
m68knommu: remove do_page_fault(), it is not used
m68knommu: use user stack pointer hardware on some ColdFire cores
m68knommu: remove command line printing DEBUG
m68knommu: remove fasthandler interrupt code
m68knommu: move UART addressing to part specific includes
m68knommu: fix clock rate value reported for ColdFire 54xx parts
m68knommu: move ColdFire CPU names into their headers
...
and saner do_signal() arguments, while we are at it
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Since commit 31c911329e ("mm: check the argument
of kunmap on architectures without highmem"), we get lots of warnings like
arch/m68k/kernel/sys_m68k.c:508: warning: passing argument 1 of ‘kunmap’ from incompatible pointer type
As m68k doesn't support highmem anyway, open code the calls to kmap() and
kunmap() (the latter is a no-op) to kill the warnings, like is done on most
other architectures without CONFIG_HIGHPTE.
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Sam Creasey <sammy@sammy.net>
Create separate functions to deal with instruction and data cache flushing.
This way we can optimize them for the vairous cache types and arrangements
used across the ColdFire family.
For example the unified caches in the version 3 cores means we don't
need to flush the instruction cache. For the version 2 cores that do
not do data cacheing (or where we choose instruction cache only) we
don't need to do any data flushing.
Signed-off-by: Greg Ungerer <gerg@uclinux.org>
The version 3 and version 4 ColdFire cache controllers support both
write-through and copy-back modes on the data cache. Allow for Kconfig
time configuration of this, and set the cache mode appropriately.
Signed-off-by: Greg Ungerer <gerg@uclinux.org>
The newer version 2 ColdFire CPU cores support a configurable cache
arrangement. The cache memory can be used as all instruction cache, all
data cache, or split in half for both instruction and data caching.
Support this setup via a Kconfig time menu that allows a kernel builder
to choose the arrangement they want to use.
Signed-off-by: Greg Ungerer <gerg@uclinux.org>
Currently the code to push cache lines is only available to version 4
cores. Version 3 cores may also need to use this if we support copy-
back caches on them. Move this code to make it more generic, and
useful for all version ColdFire cores.
With this in place we can now have a single cache_flush_all() code
path that does all the right things on all version cores.
Signed-off-by: Greg Ungerer <gerg@uclinux.org>
The cache control code for the ColdFire CPU's is a big ugly mess
of "#ifdef"ery liberally coated with bit constants. Clean it up.
The cache controllers in the various ColdFire parts are actually quite
similar. Just differing in some bit flags and options supported. Using
the header defines now in place it is pretty easy to factor out the
small differences and use common setup and flush/invalidate code.
I have preserved the cache setups as they where in the old code
(except where obviously wrong - like in the case of the 5249). Following
from this it should be easy now to extend the possible setups used on
the CACHE controllers that support split cacheing or copy-back or
write through options.
Signed-off-by: Greg Ungerer <gerg@uclinux.org>
Move the inclusion of the version 4 cache controller registers so that
it is with all the other register bit flag definitions. This makes it
consistent with the other version core inclusion points, and means we
don't need "#ifdef"ery in odd-ball places for these definitions.
Signed-off-by: Greg Ungerer <gerg@uclinux.org>
All version 3 based ColdFire CPU cores have a similar cache controller.
Merge all the exitsing definitions into a single file, and make them
similar in style and naming to the existing version 2 and version 4
cache controller definitions.
Signed-off-by: Greg Ungerer <gerg@uclinux.org>
The version 2 ColdFire CPU based cores all contain a similar cache
controller unit. Create a set of bit flag definitions for the supporting
registers.
Signed-off-by: Greg Ungerer <gerg@uclinux.org>
The more modern ColdFire parts (even if based on older version cores)
have separate user and supervisor stack pointers (a7 register).
Modify the ColdFire CPU setup and exception code to enable and use
this on parts that have it.
Signed-off-by: Greg Ungerer <gerg@uclinux.org>
The ColdFire UART base addresses varies between the different ColdFire
family members. Instead of keeping the base addresses with the UART
definitions keep them with the other addresses definitions for each
ColdFire part.
The motivation for this move is so that when we add new ColdFire
part definitions, they are all in a single file (and we shouldn't
normally need to modify the UART definitions in mcfuart.h at all).
Signed-off-by: Greg Ungerer <gerg@uclinux.org>
The instruction timings of the ColdFire 54xx family parts are
different to other version 4 parts (or version 2 or 3 parts for
that matter too).
Move the instruction timing setting into the ColdFire part
specific headers, and set the 54xx value appropriately.
Signed-off-by: Greg Ungerer <gerg@uclinux.org>
Move the ColdFire CPU names out of setup.c and into their repsective
headers. That way when we add new ones we won't need to modify
setup.c any more.
Add the missing 548x CPU name.
Signed-off-by: Greg Ungerer <gerg@uclinux.org>
The ColdFire 547x family of processors is very similar to the ColdFire
548x series. Almost all of the support for them is the same. Make the
code supporting the 548x more gneric, so it will be capable of
supporting both families.
For the most part this is a renaming excerise to make the support
code more obviously apply to both families.
Signed-off-by: Greg Ungerer <gerg@uclinux.org>
Now that we have meaningfull symbolic constants for bit definitions
of the cache registers of m5407 and m548x chips, use them to
improve readability, portability and efficiency of the cache operations.
This also fixes __flush_cache_all for m548x chips : implicit
DCACHE_SIZE was exact for m5407, but wrong for m548x.
Signed-off-by: Philippe De Muyter <phdm@macqel.be>
Signed-off-by: Greg Ungerer <gerg@uclinux.org>
__flush_cache_all for m54xx is intrinsically related to the bit
definitions in m54xxacr.h. Move it there from cacheflush_no.h,
for easier maintenance.
Signed-off-by: Philippe De Muyter <phdm@macqel.be>
Signed-off-by: Greg Ungerer <gerg@uclinux.org>
The MCF548x have the same cache control registers as the MCF5407.
Extract the bit definitions for the ACR and CACR registers from m5407sim.h
and move them to a new file m54xxacr.h. Those definitions are not used
anywhere yet, so no other file is involved. This is a preparation for
m54xx cache support cleanup.
Signed-off-by: Philippe De Muyter <phdm@macqel.be>
Signed-off-by: Greg Ungerer <gerg@uclinux.org>
Recent changes to header files made kernel compilation for m68k/m68knommu
fail with :
CC arch/m68knommu/kernel/asm-offsets.s
In file included from /archives/linux/git/arch/m68k/include/asm/system.h:2,
from include/linux/wait.h:25,
from include/linux/mmzone.h:9,
from include/linux/gfp.h:4,
from include/linux/irq.h:20,
from include/asm-generic/hardirq.h:12,
from /archives/linux/git/arch/m68k/include/asm/hardirq_no.h:17,
from /archives/linux/git/arch/m68k/include/asm/hardirq.h:2,
from include/linux/hardirq.h:10,
from /archives/linux/git/arch/m68k/include/asm/irqflags.h:5,
from include/linux/irqflags.h:15,
from include/linux/spinlock.h:53,
from include/linux/seqlock.h:29,
from include/linux/time.h:8,
from include/linux/timex.h:56,
from include/linux/sched.h:56,
from arch/m68knommu/kernel/asm-offsets.c:12:
/archives/linux/git/arch/m68k/include/asm/system_no.h: In function ‘__xchg’:
/archives/linux/git/arch/m68k/include/asm/system_no.h:79: error: implicit
+declaration of function ‘local_irq_save’
/archives/linux/git/arch/m68k/include/asm/system_no.h:101: error: implicit
+declaration of function ‘local_irq_restore’
Fix that
Signed-off-by: Philippe De Muyter <phdm@macqel.be>
Signed-off-by: Greg Ungerer <gerg@uclinux.org>
The cleanup and merge of machdep should not have removed the do_IRQ
declaration. It is needed by the 68328 based targets.
Signed-off-by: Greg Ungerer <gerg@uclinux.org>
Long ago, PT_TRACESYS_OFF and friends were introduced as hard defines to
avoid straight constants in assembler parts of linux m68k. They are not
used anymore, and were not updated to follow changes in linux kernel.
Remove them. When similar constants are needed, they are now generated
using asm-offsets.c.
Signed-off-by: Philippe De Muyter <phdm@macqel.be>
Acked-by: Mike Frysinger <vapier@gentoo.org>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Greg Ungerer <gerg@uclinux.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Since we no longer need to provide KM_type, the whole pte_*map_nested()
API is now redundant, remove it.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Chris Metcalf <cmetcalf@tilera.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: David Miller <davem@davemloft.net>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/gerg/m68knommu: (21 commits)
m68knommu: convert to using tracehook_report_syscall_*
m68knommu: some boards use fixed phy for FEC ethernet
m68knommu: support the external GPIO based interrupts of the 5272
m68knommu: mask of vector bits in exception word properly
m68knommu: change to new flag variables
m68knommu: Fix MCFUART_TXFIFOSIZE for m548x.
m68knommu: add basic mmu-less m548x support
m68knommu: .gitignore vmlinux.lds
m68knommu: stop using __do_IRQ
m68knommu: rename PT_OFF_VECTOR to PT_OFF_FORMATVEC.
m68knommu: add support for Coldfire 547x/548x interrupt controller
m68k{nommu}: Remove unused DEFINE's from asm-offsets.c
m68knommu: whitespace cleanup in 68328/entry.S
m68knommu: Document supported chips in intc-2.c and intc-simr.c.
m68knommu: fix strace support for 68328/68360
m68knommu: fix default starting date
arch/m68knommu: Removing dead 68328_SERIAL_UART2 config option
arch/m68knommu: Removing dead RAM_{16,32}_MB config option
arch/m68knommu: Removing dead M68KFPU_EMU config option
arch/m68knommu: Removing dead RELOCATE config option
...
On m68k, I/O macros like inb() outw() etc. are only defined to
something useful if CONFIG_ISA is set; dummies are in place if
not, but four macros were missing from the !CONFIG_ISA case.
Adding these makes some drivers, such as speakup, compile again.
Signed-off-by: Thorsten Glaser <tg@debian.org>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Fixes this:
drivers/char/mem.c: In function 'mmap_kmem':
drivers/char/mem.c:342: warning: cast to pointer from integer of different size
by doing what other archtiectures do.
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
The MMU and non-MMU versions of traps.h are virtually identical,
merge them into a single file.
Signed-off-by: Greg Ungerer <gerg@uclinux.org>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
The MMU and non-MMU versions of thread_info.h are quite similar.
Merge the two files.
Signed-off-by: Greg Ungerer <gerg@uclinux.org>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
The only difference between the MMU and non-MMU versions of atomic.h
is some extra support needed by ColdFire family processors. So merge
this into the MMU version of atomic.h.
Signed-off-by: Greg Ungerer <gerg@uclinux.org>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
There is a lot of common defines in the MMU and non-MMU variants of
page.h. Factor out the common stuff into the master page.h. It still
includes the underlying page_mm.h or page_no.h, but they only contain
the real differences now.
Signed-off-by: Greg Ungerer <gerg@uclinux.org>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
No need to have separate machdep.h files for each of the MMU and non-MMU
cases. Merge them all into a single file.
Signed-off-by: Greg Ungerer <gerg@uclinux.org>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
The MMU and non-MMU string.h varients (string_no.h and string_mm.h)
and almost the same. Switch to using the string_mm.h one, merging
in the necessary ColdFire support.
Signed-off-by: Greg Ungerer <gerg@uclinux.org>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
CONFIG_SMP doesn't exist in Kconfig (for this architecure), therefore
remove all references to it from the source.
Signed-off-by: Christian Dietrich <qy03fugy@stud.informatik.uni-erlangen.de>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Move the definition of THREAD_SIZE from page_mm.h to thread_info_mm.h
This logically associates it with the other thread definitions, and will
make it easier to merge the MMU and non-MMU versions of page.h and
thread_info.h.
Signed-off-by: Greg Ungerer <gerg@uclinux.org>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
This patch converts m68k to use asm-generic/ioctls.h instead of its
own version.
The differences between the arch-specific version and the generic
version are as follows:
- m68k defines its own value for FIOQSIZE, asm-generic/ioctls.h keeps it
- The generic version adds TIOCSRS485 and TIOCGRS485m which are unused
by any driver available on this architecture.
- The generic version adds support for termiox
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Roman Zippel <zippel@linux-m68k.org>
Cc: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
CONFIG_GG2 doesn't exist in Kconfig, therefore remove
all references to it from the source.
Signed-off-by: Christian Dietrich <qy03fugy@stud.informatik.uni-erlangen.de>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Serial lines on the MCF548x have really big fifos : 512 bytes.
Signed-off-by: Philippe De Muyter <phdm@macqel.be>
Signed-off-by: Greg Ungerer <gerg@uclinux.org>
Add a very basic mmu-less support for coldfire m548x family. This is perhaps
also valid for m547x family. The port comprises the serial, tick timer and
reboot support. The gpio part compiles but is empty. This gives a functional
albeit limited linux for the m548x coldfire family. This has been tested
on a Freescale M548xEVB Lite board with a M5484 processor and the default
dbug monitor.
Signed-off-by: Philippe De Muyter <phdm@macqel.be>
Signed-off-by: Greg Ungerer <gerg@uclinux.org>
Fix the IRQ flag handling naming. In linux/irqflags.h under one configuration,
it maps:
local_irq_enable() -> raw_local_irq_enable()
local_irq_disable() -> raw_local_irq_disable()
local_irq_save() -> raw_local_irq_save()
...
and under the other configuration, it maps:
raw_local_irq_enable() -> local_irq_enable()
raw_local_irq_disable() -> local_irq_disable()
raw_local_irq_save() -> local_irq_save()
...
This is quite confusing. There should be one set of names expected of the
arch, and this should be wrapped to give another set of names that are expected
by users of this facility.
Change this to have the arch provide:
flags = arch_local_save_flags()
flags = arch_local_irq_save()
arch_local_irq_restore(flags)
arch_local_irq_disable()
arch_local_irq_enable()
arch_irqs_disabled_flags(flags)
arch_irqs_disabled()
arch_safe_halt()
Then linux/irqflags.h wraps these to provide:
raw_local_save_flags(flags)
raw_local_irq_save(flags)
raw_local_irq_restore(flags)
raw_local_irq_disable()
raw_local_irq_enable()
raw_irqs_disabled_flags(flags)
raw_irqs_disabled()
raw_safe_halt()
with type checking on the flags 'arguments', and then wraps those to provide:
local_save_flags(flags)
local_irq_save(flags)
local_irq_restore(flags)
local_irq_disable()
local_irq_enable()
irqs_disabled_flags(flags)
irqs_disabled()
safe_halt()
with tracing included if enabled.
The arch functions can now all be inline functions rather than some of them
having to be macros.
Signed-off-by: David Howells <dhowells@redhat.com> [X86, FRV, MN10300]
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com> [Tile]
Signed-off-by: Michal Simek <monstr@monstr.eu> [Microblaze]
Tested-by: Catalin Marinas <catalin.marinas@arm.com> [ARM]
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Haavard Skinnemoen <haavard.skinnemoen@atmel.com> [AVR]
Acked-by: Tony Luck <tony.luck@intel.com> [IA-64]
Acked-by: Hirokazu Takata <takata@linux-m32r.org> [M32R]
Acked-by: Greg Ungerer <gerg@uclinux.org> [M68K/M68KNOMMU]
Acked-by: Ralf Baechle <ralf@linux-mips.org> [MIPS]
Acked-by: Kyle McMartin <kyle@mcmartin.ca> [PA-RISC]
Acked-by: Paul Mackerras <paulus@samba.org> [PowerPC]
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com> [S390]
Acked-by: Chen Liqin <liqin.chen@sunplusct.com> [Score]
Acked-by: Matt Fleming <matt@console-pimps.org> [SH]
Acked-by: David S. Miller <davem@davemloft.net> [Sparc]
Acked-by: Chris Zankel <chris@zankel.net> [Xtensa]
Reviewed-by: Richard Henderson <rth@twiddle.net> [Alpha]
Reviewed-by: Yoshinori Sato <ysato@users.sourceforge.jp> [H8300]
Cc: starvik@axis.com [CRIS]
Cc: jesper.nilsson@axis.com [CRIS]
Cc: linux-cris-kernel@axis.com
The arch/m68k/include/asm/ide.h produces errors when the IDE driver is compiled for my 523x uClinux system under kernel. The header makes some redefines of operators not defined in the arch/m68k/include/asm/io_no.h header. There are no separate mmio and iospace defines.
Signed-off-by: Jate Sujjavanich <jsujjavanich@syntech-fuelmaster.com>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Greg Ungerer <gerg@uclinux.org>
Architectures implement dma_is_consistent() in different ways (some
misinterpret the definition of API in DMA-API.txt). So it hasn't been so
useful for drivers. We have only one user of the API in tree. Unlikely
out-of-tree drivers use the API.
Even if we fix dma_is_consistent() in some architectures, it doesn't look
useful at all. It was invented long ago for some old systems that can't
allocate coherent memory at all. It's better to export only APIs that are
definitely necessary for drivers.
Let's remove this API.
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
dma_get_cache_alignment returns the minimum DMA alignment. Architectures
defines it as ARCH_DMA_MINALIGN (formally ARCH_KMALLOC_MINALIGN). So we
can unify dma_get_cache_alignment implementations.
Note that some architectures implement dma_get_cache_alignment wrongly.
dma_get_cache_alignment() should return the minimum DMA alignment. So
fully-coherent architectures should return 1. This patch also fixes this
issue.
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Now each architecture has the own dma_get_cache_alignment implementation.
dma_get_cache_alignment returns the minimum DMA alignment. Architectures
define it as ARCH_KMALLOC_MINALIGN (it's used to make sure that malloc'ed
buffer is DMA-safe; the buffer doesn't share a cache with the others). So
we can unify dma_get_cache_alignment implementations.
This patch:
dma_get_cache_alignment() needs to know if an architecture defines
ARCH_KMALLOC_MINALIGN or not (needs to know if architecture has DMA
alignment restriction). However, slab.h define ARCH_KMALLOC_MINALIGN if
architectures doesn't define it.
Let's rename ARCH_KMALLOC_MINALIGN to ARCH_DMA_MINALIGN.
ARCH_KMALLOC_MINALIGN is used only in the internals of slab/slob/slub
(except for crypto).
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'for-2.6.36' of git://git.kernel.dk/linux-2.6-block: (149 commits)
block: make sure that REQ_* types are seen even with CONFIG_BLOCK=n
xen-blkfront: fix missing out label
blkdev: fix blkdev_issue_zeroout return value
block: update request stacking methods to support discards
block: fix missing export of blk_types.h
writeback: fix bad _bh spinlock nesting
drbd: revert "delay probes", feature is being re-implemented differently
drbd: Initialize all members of sync_conf to their defaults [Bugz 315]
drbd: Disable delay probes for the upcomming release
writeback: cleanup bdi_register
writeback: add new tracepoints
writeback: remove unnecessary init_timer call
writeback: optimize periodic bdi thread wakeups
writeback: prevent unnecessary bdi threads wakeups
writeback: move bdi threads exiting logic to the forker thread
writeback: restructure bdi forker loop a little
writeback: move last_active to bdi
writeback: do not remove bdi from bdi_list
writeback: simplify bdi code a little
writeback: do not lose wake-ups in bdi threads
...
Fixed up pretty trivial conflicts in drivers/block/virtio_blk.c and
drivers/scsi/scsi_error.c as per Jens.
This patch is against the 2.6.34 source.
Paraphrased from the 1989 BSD patch by David Borman @ cray.com:
These are the changes needed for the kernel to support
LINEMODE in the server.
There is a new bit in the termios local flag word, EXTPROC.
When this bit is set, several aspects of the terminal driver
are disabled. Input line editing, character echo, and mapping
of signals are all disabled. This allows the telnetd to turn
off these functions when in linemode, but still keep track of
what state the user wants the terminal to be in.
New ioctl:
TIOCSIG Generate a signal to processes in the
current process group of the pty.
There is a new mode for packet driver, the TIOCPKT_IOCTL bit.
When packet mode is turned on in the pty, and the EXTPROC bit
is set, then whenever the state of the pty is changed, the
next read on the master side of the pty will have the TIOCPKT_IOCTL
bit set. This allows the process on the server side of the pty
to know when the state of the terminal has changed; it can then
issue the appropriate ioctl to retrieve the new state.
Since the original BSD patches accompanied the source code for telnet
I've left that reference here, but obviously the feature is useful for
any remote terminal protocol, including ssh.
The corresponding feature has existed in the BSD tty driver since 1989.
For historical reference, a good copy of the relevant files can be found
here:
http://anonsvn.mit.edu/viewvc/krb5/trunk/src/appl/telnet/?pathrev=17741
Signed-off-by: Howard Chu <hyc@symas.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>