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path: root/drivers/net/slip.c
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2011-08-27slip: Move the SLIP driversJeff Kirsher1-1444/+0
Move the Serial Line Internet Protocol (SLIP) drivers into drivers/net/slip/ and make the necessary Kconfig and Makefile changes. Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com> Acked-by: Alan Cox <alan@linux.intel.com>
2011-08-08Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/netDavid S. Miller1-1/+1
2011-08-08slip: fix NOHZ local_softirq_pending 08 warningMatvejchikov Ilya1-1/+1
When using nanosleep() in an userspace application we get a ratelimit warning: NOHZ: local_softirq_pending 08 According to 481a8199142c050b72bff8a1956a49fd0a75bbe0 the problem is caused by netif_rx() function. This patch replaces netif_rx() with netif_rx_ni() which has to be used from process/softirq context. Signed-off-by: Matvejchikov Ilya <matvejchikov@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-08-04slip: cleanup statistics generationMatvejchikov Ilya1-15/+14
Remove unused tx_compressed, tx_compressed and tx_misses fields from the slip structure. Also, make some device stats generation cleanups. Signed-off-by: Matvejchikov Ilya <matvejchikov@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-20slip: remove unused 'line' field from the 'slip' structureMatvejchikov Ilya1-3/+0
Signed-off-by: Matvejchikov Ilya <matvejchikov@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-14Merge branch 'master' of ↵David S. Miller1-1/+1
master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6 Conflicts: net/bluetooth/l2cap_core.c
2011-07-13slip: remove dead code within the slip initializationMatvejchikov Ilya1-18/+6
This following code contains a dead "if (dev).." block: ... for (i = 0; i < slip_maxdev; i++) { dev = slip_devs[i]; if (dev == NULL) break; } /* Sorry, too many, all slots in use */ if (i >= slip_maxdev) return NULL; if (dev) { sl = netdev_priv(dev); if (test_bit(SLF_INUSE, &sl->flags)) { unregister_netdevice(dev); dev = NULL; slip_devs[i] = NULL; } } ... The reason is that the code starting with "if (dev).." is never called as when we found an empty slot (dev == NULL) we break the loop and "if (dev).." not works eiter the loop ends and we get out with "i >= slip_maxdev". Signed-off-by: Matvejchikov Ilya <matvejchikov@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-13slip: remove redundant check slip_devs for NULLMatvejchikov Ilya1-3/+0
As slip_devs is initialized on module load stage there is no reason to check it for NULL anywhere instead of the deinitialization routine because if we can't get enough memory on startup we don't run at all. Signed-off-by: Matvejchikov Ilya <matvejchikov@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-13slip: fix MTU comparation operation when reallocating buffersMatvejchikov Ilya1-1/+1
In sl_realloc_bufs() there is no reason to check if the requested MTU greater than or equal to the current MTU value as this function called only when requested MTU not equals to the current value. So, the ">=" operation can be safely replaced with the ">". Signed-off-by: Matvejchikov Ilya <matvejchikov@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-13slip: remove redundant NULL-pointer check before calling slhc_freeMatvejchikov Ilya1-2/+1
Signed-off-by: Matvejchikov Ilya <matvejchikov@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-12slip: fix wrong SLIP6 ifdef-endif placingMatvejchikov Ilya1-1/+1
SLIP6 have nothing to do with CSLIP so placing a block of SLIP6-related code within a CSLIP ifdef-endif block is incorrect. Signed-off-by: Ilya Matvejchikov <matvejchikov@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-06-04Revert "tty: make receive_buf() return the amout of bytes received"Linus Torvalds1-7/+4
This reverts commit b1c43f82c5aa265442f82dba31ce985ebb7aa71c. It was broken in so many ways, and results in random odd pty issues. It re-introduced the buggy schedule_work() in flush_to_ldisc() that can cause endless work-loops (see commit a5660b41af6a: "tty: fix endless work loop when the buffer fills up"). It also used an "unsigned int" return value fo the ->receive_buf() function, but then made multiple functions return a negative error code, and didn't actually check for the error in the caller. And it didn't actually work at all. BenH bisected down odd tty behavior to it: "It looks like the patch is causing some major malfunctions of the X server for me, possibly related to PTYs. For example, cat'ing a large file in a gnome terminal hangs the kernel for -minutes- in a loop of what looks like flush_to_ldisc/workqueue code, (some ftrace data in the quoted bits further down). ... Some more data: It -looks- like what happens is that the flush_to_ldisc work queue entry constantly re-queues itself (because the PTY is full ?) and the workqueue thread will basically loop forver calling it without ever scheduling, thus starving the consumer process that could have emptied the PTY." which is pretty much exactly the problem we fixed in a5660b41af6a. Milton Miller pointed out the 'unsigned int' issue. Reported-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Reported-by: Milton Miller <miltonm@bga.com> Cc: Stefan Bigler <stefan.bigler@keymile.com> Cc: Toby Gray <toby.gray@realvnc.com> Cc: Felipe Balbi <balbi@ti.com> Cc: Greg Kroah-Hartman <gregkh@suse.de> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-05-23Merge branch 'tty-next' of ↵Linus Torvalds1-4/+7
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty-2.6 * 'tty-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty-2.6: (48 commits) serial: 8250_pci: add support for Cronyx Omega PCI multiserial board. tty/serial: Fix break handling for PORT_TEGRA tty/serial: Add explicit PORT_TEGRA type n_tracerouter and n_tracesink ldisc additions. Intel PTI implementaiton of MIPI 1149.7. Kernel documentation for the PTI feature. export kernel call get_task_comm(). tty: Remove to support serial for S5P6442 pch_phub: Support new device ML7223 8250_pci: Add support for the Digi/IBM PCIe 2-port Adapter ASoC: Update cx20442 for TTY API change pch_uart: Support new device ML7223 IOH parport: Use request_muxed_region for IT87 probe and lock tty/serial: add support for Xilinx PS UART n_gsm: Use print_hex_dump_bytes drivers/tty/moxa.c: Put correct tty value TTY: tty_io, annotate locking functions TTY: serial_core, remove superfluous set_task_state TTY: serial_core, remove invalid test Char: moxa, fix locking in moxa_write ... Fix up trivial conflicts in drivers/bluetooth/hci_ldisc.c and drivers/tty/serial/Makefile. I did the hci_ldisc thing as an evil merge, cleaning things up.
2011-05-09NET: slip, fix ldisc->open retvalMatvejchikov Ilya1-1/+3
TTY layer expects 0 if the ldisc->open operation succeeded. Signed-off-by : Matvejchikov Ilya <matvejchikov@gmail.com> Acked-by: Oliver Hartkopp <socketcan@hartkopp.net> Acked-by: Alan Cox <alan@linux.intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-04-23tty: make receive_buf() return the amout of bytes receivedFelipe Balbi1-4/+7
it makes it simpler to keep track of the amount of bytes received and simplifies how flush_to_ldisc counts the remaining bytes. It also fixes a bug of lost bytes on n_tty when flushing too many bytes via the USB serial gadget driver. Tested-by: Stefan Bigler <stefan.bigler@keymile.com> Tested-by: Toby Gray <toby.gray@realvnc.com> Signed-off-by: Felipe Balbi <balbi@ti.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-09-27drivers/net: return operator cleanupEric Dumazet1-1/+1
Change "return (EXPR);" to "return EXPR;" return is not a function, parentheses are not required. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-08-28slip: Use net_device_stats from struct net_deviceTobias Klauser1-30/+31
Use net_device->stats for stats instead of private variable copies in struct slip. Use ndo_get_stat64 so the additions can be performed on a private destination buffer. Cc: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: Tobias Klauser <tklauser@distanz.ch> Acked-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-08-19slip: fix get_stats() methodEric Dumazet1-25/+25
Use integrated net_device_stats instead of a static one, and make sure no transient values are feeded. ndo_get_stats() can be called by concurrent cpus. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-05-18drivers/net: remove useless semicolonsJoe Perches1-1/+1
switch and while statements don't need semicolons at end of statement [ Fixup minor conflicts with recent wimax merge... -DaveM ] Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-05-10net: trans_start cleanupsEric Dumazet1-1/+1
Now that core network takes care of trans_start updates, dont do it in drivers themselves, if possible. Drivers can avoid one cache miss (on dev->trans_start) in their start_xmit() handler. Exceptions are NETIF_F_LLTX drivers Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-03-30include cleanup: Update gfp.h and slab.h includes to prepare for breaking ↵Tejun Heo1-0/+1
implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2009-12-04drivers/net: Move && and || to end of previous lineJoe Perches1-4/+4
Only files where David Miller is the primary git-signer. wireless, wimax, ixgbe, etc are not modified. Compile tested x86 allyesconfig only Not all files compiled (not x86 compatible) Added a few > 80 column lines, which I ignored. Existing checkpatch complaints ignored. Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-11-19Merge branch 'master' of ↵David S. Miller1-0/+1
master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6 Conflicts: drivers/net/sfc/sfe4001.c drivers/net/wireless/libertas/cmd.c drivers/staging/Kconfig drivers/staging/Makefile drivers/staging/rtl8187se/Kconfig drivers/staging/rtl8192e/Kconfig
2009-11-07net, compat_ioctl: handle socket ioctl abuses in tty driversArnd Bergmann1-0/+25
Slip and a few other drivers use the same ioctl numbers on tty devices that are normally meant for sockets. This causes problems with our compat_ioctl handling that tries to convert the data structures in a different format. Fortunately, these five drivers all use 32 bit compatible data structures in the ioctl numbers, so we can just add a trivial compat_ioctl conversion function to each of them. SIOCSIFENCAP and SIOCGIFENCAP do not need to live in fs/compat_ioctl.c after this any more, and they are not used on any sockets. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-10-11headers: remove sched.h from interrupt.hAlexey Dobriyan1-0/+1
After m68k's task_thread_info() doesn't refer to current, it's possible to remove sched.h from interrupt.h and not break m68k! Many thanks to Heiko Carstens for allowing this. Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
2009-09-20slip: Clean up create and destroyAlan Cox1-73/+23
The network layer now has a destructor we can hook to clean up the slip devices array. That needs us to initiate unregister events in the right places which with the current tty layer we can do, and with network refcounting is safe to do. Signed-off-by: Alan Cox <alan@lxorguk.ukuu.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-09-01netdev: convert pseudo drivers to netdev_tx_tStephen Hemminger1-1/+1
These are all drivers that don't touch real hardware. Signed-off-by: Stephen Hemminger <shemminger@vyatta.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-07-06net: use NETDEV_TX_OK instead of 0 in ndo_start_xmit() functionsPatrick McHardy1-3/+3
This patch is the result of an automatic spatch transformation to convert all ndo_start_xmit() return values of 0 to NETDEV_TX_OK. Some occurences are missed by the automatic conversion, those will be handled in a seperate patch. Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-01-08slip: convert to net_device_opsStephen Hemminger1-11/+17
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-12-06tty: Flags should be accessed via the foo_bit interfacesAlan Cox1-6/+5
We have various drivers that poke around directly and we need to clean this up before it causes problems. Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-11-04drivers/net: Kill now superfluous ->last_rx stores.David S. Miller1-1/+0
The generic packet receive code takes care of setting netdev->last_rx when necessary, for the sake of the bonding ARP monitor. Drivers need not do it any more. Some cases had to be skipped over because the drivers were making use of the ->last_rx value themselves. Signed-off-by: David S. Miller <davem@davemloft.net>
2008-07-21tty: Ldisc revampAlan Cox1-1/+1
Move the line disciplines towards a conventional ->ops arrangement. For the moment the actual 'tty_ldisc' struct in the tty is kept as part of the tty struct but this can then be changed if it turns out that when it all settles down we want to refcount ldiscs separately to the tty. Pull the ldisc code out of /proc and put it with our ldisc code. Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30tty: The big operations reworkAlan Cox1-5/+8
- Operations are now a shared const function block as with most other Linux objects - Introduce wrappers for some optional functions to get consistent behaviour - Wrap put_char which used to be patched by the tty layer - Document which functions are needed/optional - Make put_char report success/fail - Cache the driver->ops pointer in the tty as tty->ops - Remove various surplus lock calls we no longer need - Remove proc_write method as noted by Alexey Dobriyan - Introduce some missing sanity checks where certain driver/ldisc combinations would oops as they didn't check needed methods were present [akpm@linux-foundation.org: fix fs/compat_ioctl.c build] [akpm@linux-foundation.org: fix isicom] [akpm@linux-foundation.org: fix arch/ia64/hp/sim/simserial.c build] [akpm@linux-foundation.org: fix kgdb] Signed-off-by: Alan Cox <alan@redhat.com> Acked-by: Greg Kroah-Hartman <gregkh@suse.de> Cc: Jason Wessel <jason.wessel@windriver.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-01-29slip: Drag kicking and screaming into coding style complianceAlan Cox1-189/+178
Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-11-07[TTY]: Use tty_mode_ioctl() in network drivers.Alan Cox1-7/+1
We conciously make a change here - we permit mode and speed setting to be done in things like SLIP mode. There isn't actually a technical reason to disallow this. It's usually a silly thing to do but we can do it and soemone might wish to do so. Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-11[NET]: Nuke SET_MODULE_OWNER macro.Ralf Baechle1-2/+0
It's been a useless no-op for long enough in 2.6 so I figured it's time to remove it. The number of people that could object because they're maintaining unified 2.4 and 2.6 drivers is probably rather small. [ Handled drivers added by netdev tree and some missed IRDA cases... -DaveM ] Signed-off-by: Ralf Baechle <ralf@linux-mips.org> Signed-off-by: Jeff Garzik <jeff@garzik.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-08-27[SLIP]: trivial sparse warning fixStephen Hemminger1-1/+1
Function declared static in forward declaration, but not in actual code. Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-26[SK_BUFF]: Introduce skb_mac_header()Arnaldo Carvalho de Melo1-1/+1
For the places where we need a pointer to the mac header, it is still legal to touch skb->mac.raw directly if just adding to, subtracting from or setting it to another layer header. This one also converts some more cases to skb_reset_mac_header() that my regex missed as it had no spaces before nor after '=', ugh. Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-02-08[NET] slip: Replace kmalloc() + memset() pairs with the appropriate ↵Joe Jin1-4/+1
kzalloc() calls This patch replace kmalloc() + memset() pairs with the appropriate kzalloc(). Signed-off-by: Joe Jin <joe.jin@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-12-13[PATCH] getting rid of all casts of k[cmz]alloc() callsRobert P. J. Day1-3/+3
Run this: #!/bin/sh for f in $(grep -Erl "\([^\)]*\) *k[cmz]alloc" *) ; do echo "De-casting $f..." perl -pi -e "s/ ?= ?\([^\)]*\) *(k[cmz]alloc) *\(/ = \1\(/" $f done And then go through and reinstate those cases where code is casting pointers to non-pointers. And then drop a few hunks which conflicted with outstanding work. Cc: Russell King <rmk@arm.linux.org.uk>, Ian Molton <spyro@f2s.com> Cc: Mikael Starvik <starvik@axis.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Cc: Roman Zippel <zippel@linux-m68k.org> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Kyle McMartin <kyle@mcmartin.ca> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Jeff Dike <jdike@addtoit.com> Cc: Greg KH <greg@kroah.com> Cc: Jens Axboe <jens.axboe@oracle.com> Cc: Paul Fulghum <paulkf@microgate.com> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: Karsten Keil <kkeil@suse.de> Cc: Mauro Carvalho Chehab <mchehab@infradead.org> Cc: Jeff Garzik <jeff@garzik.org> Cc: James Bottomley <James.Bottomley@steeleye.com> Cc: Ian Kent <raven@themaw.net> Cc: Steven French <sfrench@us.ibm.com> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Neil Brown <neilb@cse.unsw.edu.au> Cc: Jaroslav Kysela <perex@suse.cz> Cc: Takashi Iwai <tiwai@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-13drivers/net: Trim trailing whitespaceJeff Garzik1-16/+16
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2006-06-30Remove obsolete #include <linux/config.h>Jörn Engel1-1/+0
Signed-off-by: Jörn Engel <joern@wohnheim.fh-wedel.de> Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-01-10[PATCH] TTY layer buffering revampAlan Cox1-10/+1
The API and code have been through various bits of initial review by serial driver people but they definitely need to live somewhere for a while so the unconverted drivers can get knocked into shape, existing drivers that have been updated can be better tuned and bugs whacked out. This replaces the tty flip buffers with kmalloc objects in rings. In the normal situation for an IRQ driven serial port at typical speeds the behaviour is pretty much the same, two buffers end up allocated and the kernel cycles between them as before. When there are delays or at high speed we now behave far better as the buffer pool can grow a bit rather than lose characters. This also means that we can operate at higher speeds reliably. For drivers that receive characters in blocks (DMA based, USB and especially virtualisation) the layer allows a lot of driver specific code that works around the tty layer with private secondary queues to be removed. The IBM folks need this sort of layer, the smart serial port people do, the virtualisers do (because a virtualised tty typically operates at infinite speed rather than emulating 9600 baud). Finally many drivers had invalid and unsafe attempts to avoid buffer overflows by directly invoking tty methods extracted out of the innards of work queue structs. These are no longer needed and all go away. That fixes various random hangs with serial ports on overflow. The other change in here is to optimise the receive_room path that is used by some callers. It turns out that only one ldisc uses receive room except asa constant and it updates it far far less than the value is read. We thus make it a variable not a function call. I expect the code to contain bugs due to the size alone but I'll be watching and squashing them and feeding out new patches as it goes. Because the buffers now dynamically expand you should only run out of buffering when the kernel runs out of memory for real. That means a lot of the horrible hacks high performance drivers used to do just aren't needed any more. Description: tty_insert_flip_char is an old API and continues to work as before, as does tty_flip_buffer_push() [this is why many drivers dont need modification]. It does now also return the number of chars inserted There are also tty_buffer_request_room(tty, len) which asks for a buffer block of the length requested and returns the space found. This improves efficiency with hardware that knows how much to transfer. and tty_insert_flip_string_flags(tty, str, flags, len) to insert a string of characters and flags For a smart interface the usual code is len = tty_request_buffer_room(tty, amount_hardware_says); tty_insert_flip_string(tty, buffer_from_card, len); More description! At the moment tty buffers are attached directly to the tty. This is causing a lot of the problems related to tty layer locking, also problems at high speed and also with bursty data (such as occurs in virtualised environments) I'm working on ripping out the flip buffers and replacing them with a pool of dynamically allocated buffers. This allows both for old style "byte I/O" devices and also helps virtualisation and smart devices where large blocks of data suddenely materialise and need storing. So far so good. Lots of drivers reference tty->flip.*. Several of them also call directly and unsafely into function pointers it provides. This will all break. Most drivers can use tty_insert_flip_char which can be kept as an API but others need more. At the moment I've added the following interfaces, if people think more will be needed now is a good time to say int tty_buffer_request_room(tty, size) Try and ensure at least size bytes are available, returns actual room (may be zero). At the moment it just uses the flipbuf space but that will change. Repeated calls without characters being added are not cumulative. (ie if you call it with 1, 1, 1, and then 4 you'll have four characters of space. The other functions will also try and grow buffers in future but this will be a more efficient way when you know block sizes. int tty_insert_flip_char(tty, ch, flag) As before insert a character if there is room. Now returns 1 for success, 0 for failure. int tty_insert_flip_string(tty, str, len) Insert a block of non error characters. Returns the number inserted. int tty_prepare_flip_string(tty, strptr, len) Adjust the buffer to allow len characters to be added. Returns a buffer pointer in strptr and the length available. This allows for hardware that needs to use functions like insl or mencpy_fromio. Signed-off-by: Alan Cox <alan@redhat.com> Cc: Paul Fulghum <paulkf@microgate.com> Signed-off-by: Hirokazu Takata <takata@linux-m32r.org> Signed-off-by: Serge Hallyn <serue@us.ibm.com> Signed-off-by: Jeff Dike <jdike@addtoit.com> Signed-off-by: John Hawkes <hawkes@sgi.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-29[NET]: drivers/net/slip.c needs linux/delay.hDavid S. Miller1-0/+1
For msleep_interruptible(). Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-27[PATCH] net/slip: replace schedule_timeout() with msleep_interruptible()Nishanth Aravamudan1-4/+2
Use msleep_interruptible() instead of schedule_timeout() to guarantee the task delays as expected.
2005-06-24[SLIP]: Simplify sl_free_bufs()Jesper Juhl1-10/+4
We can avoid assignments to the local variable 'tmp' and actually get rid of tmp alltogether in sl_free_bufs(). This patch does that. This is safe since both kfree() and slhc_free() handles NULL pointers gracefully. Signed-off-by: Jesper Juhl <juhl-lkml@dif.dk> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-23[PATCH] Convert users to tty_unregister_ldisc()Alexey Dobriyan1-1/+1
tty_register_ldisc(N_FOO, NULL) => tty_unregister_ldisc(N_FOO) Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-04-25[SLIP]: Remove redundant NULL pointer checks prior to kfreeJesper Juhl1-18/+12
Signed-off-by: Jesper Juhl <juhl-lkml@dif.dk> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-04-17Linux-2.6.12-rc2Linus Torvalds1-0/+1522
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!