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path: root/drivers/net/ppp_synctty.c
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2010-08-04ppp: make channel_ops conststephen hemminger
The PPP channel ops structure should be const. Cleanup the declarations to use standard C99 format. Signed-off-by: Stephen Hemminger <shemminger@vyatta.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 Heo
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>
2009-12-03drivers/net: Move && and || to end of previous lineJoe Perches
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>
2009-10-07net/ppp: fix comments - ppp_{sync,asynctty}_receive() may sleepTilman Schmidt
The receive_buf methods of the N_PPP and N_SYNC_PPP line disciplines, ppp_asynctty_receive() and ppp_sync_receive(), call tty_unthrottle() which may sleep. Fix the comments claiming otherwise. Impact: documentation Signed-off-by: Tilman Schmidt <tilman@imap.cc> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-07-16Revert "ppp: Fix throttling bugs"Linus Torvalds
This reverts commit a6540f731d506d9e82444cf0020e716613d4c46c, as requested by Alan: "... as it was wrong, the pty code is now fixed and the fact this isn't reverted is breaking pptp setups." Requested-by: Alan Cox <alan@lxorguk.ukuu.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-22ppp: Fix throttling bugsAlan Cox
The ppp layer goes around calling the unthrottle method from non sleeping paths. This isn't safe because the unthrottle methods in the tty layer need to be able to sleep (consider a USB dongle). Until now this didn't show up because the ppp layer never actually throttled a port so the unthrottle was always a no-op. Currently it's a mutex taking path so warnings are spewed if the unthrottle occurs via certain paths. Fix this by removing the unneccessary unthrottle calls. Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-03-13ppp: ppp_mp_explode() redesignGabriele Paoloni
I found the PPP subsystem to not work properly when connecting channels with different speeds to the same bundle. Problem Description: As the "ppp_mp_explode" function fragments the sk_buff buffer evenly among the PPP channels that are connected to a certain PPP unit to make up a bundle, if we are transmitting using an upper layer protocol that requires an Ack before sending the next packet (like TCP/IP for example), we will have a bandwidth bottleneck on the slowest channel of the bundle. Let's clarify by an example. Let's consider a scenario where we have two PPP links making up a bundle: a slow link (10KB/sec) and a fast link (1000KB/sec) working at the best (full bandwidth). On the top we have a TCP/IP stack sending a 1000 Bytes sk_buff buffer down to the PPP subsystem. The "ppp_mp_explode" function will divide the buffer in two fragments of 500B each (we are neglecting all the headers, crc, flags etc?.). Before the TCP/IP stack sends out the next buffer, it will have to wait for the ACK response from the remote peer, so it will have to wait for both fragments to have been sent over the two PPP links, received by the remote peer and reconstructed. The resulting behaviour is that, rather than having a bundle working @1010KB/sec (the sum of the channels bandwidths), we'll have a bundle working @20KB/sec (the double of the slowest channels bandwidth). Problem Solution: The problem has been solved by redesigning the "ppp_mp_explode" function in such a way to make it split the sk_buff buffer according to the speeds of the underlying PPP channels (the speeds of the serial interfaces respectively attached to the PPP channels). Referring to the above example, the redesigned "ppp_mp_explode" function will now divide the 1000 Bytes buffer into two fragments whose sizes are set according to the speeds of the channels where they are going to be sent on (e.g . 10 Byets on 10KB/sec channel and 990 Bytes on 1000KB/sec channel). The reworked function grants the same performances of the original one in optimal working conditions (i.e. a bundle made up of PPP links all working at the same speed), while greatly improving performances on the bundles made up of channels working at different speeds. Signed-off-by: Gabriele Paoloni <gabriele.paoloni@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-02-26ppp: remove some pointless conditionals before kfree_skb()Wei Yongjun
Remove some pointless conditionals before kfree_skb(). Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-12-25drivers/net: Remove redundant testJulia Lawall
In each case, ap is checked not to be NULL a few lines before. A simplified version of the semantic patch that makes this change is as follows: (http://www.emn.fr/x-info/coccinelle/) // <smpl> @r exists@ local idexpression x; expression E; position p1,p2; @@ if (x@p1 == NULL || ...) { ... when forall return ...; } ... when != \(x=E\|x--\|x++\|--x\|++x\|x-=E\|x+=E\|x|=E\|x&=E\|&x\) ( x@p2 == NULL | x@p2 != NULL ) // another path to the test that is not through p1? @s exists@ local idexpression r.x; position r.p1,r.p2; @@ ... when != x@p1 ( x@p2 == NULL | x@p2 != NULL ) @fix depends on !s@ position r.p1,r.p2; expression x,E; statement S1,S2; @@ ( - if ((x@p2 != NULL) || ...) S1 | - if ((x@p2 == NULL) && ...) S1 | - BUG_ON(x@p2 == NULL); ) // </smpl> Signed-off-by: Julia Lawall <julia@diku.dk> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-07-20tty: Ldisc revampAlan Cox
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: add throttle/unthrottle helpersAlan Cox
Something Arjan suggested which allows us to clean up the code nicely Signed-off-by: Alan Cox <alan@redhat.com> Cc: Arjan van de Ven <arjan@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30tty: The big operations reworkAlan Cox
- 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>
2008-01-28[PPP]: Sparse warning fixes.Stephen Hemminger
Fix a bunch of warnings in PPP and related drivers. Mostly because sparse doesn't like it when the the function is only marked private in the forward declaration. Signed-off-by: Stephen Hemminger <shemminger@vyatta.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28[PPP] synchronous tty: convert dead_sem to completionMatthias Kaehlcke
PPP synchronous tty channel driver: convert the semaphore dead_sem to a completion Signed-off-by: Matthias Kaehlcke <matthias.kaehlcke@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-11-12[PPP]: Remove ptr comparisons to 0Joe Perches
fix sparse warnings "Using plain integer as NULL pointer" Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-11-07[TTY]: Use tty_mode_ioctl() in network drivers.Alan Cox
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>
2007-07-19some kmalloc/memset ->kzalloc (tree wide)Yoann Padioleau
Transform some calls to kmalloc/memset to a single kzalloc (or kcalloc). Here is a short excerpt of the semantic patch performing this transformation: @@ type T2; expression x; identifier f,fld; expression E; expression E1,E2; expression e1,e2,e3,y; statement S; @@ x = - kmalloc + kzalloc (E1,E2) ... when != \(x->fld=E;\|y=f(...,x,...);\|f(...,x,...);\|x=E;\|while(...) S\|for(e1;e2;e3) S\) - memset((T2)x,0,E1); @@ expression E1,E2,E3; @@ - kzalloc(E1 * E2,E3) + kcalloc(E1,E2,E3) [akpm@linux-foundation.org: get kcalloc args the right way around] Signed-off-by: Yoann Padioleau <padator@wanadoo.fr> Cc: Richard Henderson <rth@twiddle.net> Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru> Acked-by: Russell King <rmk@arm.linux.org.uk> Cc: Bryan Wu <bryan.wu@analog.com> Acked-by: Jiri Slaby <jirislaby@gmail.com> Cc: Dave Airlie <airlied@linux.ie> Acked-by: Roland Dreier <rolandd@cisco.com> Cc: Jiri Kosina <jkosina@suse.cz> Acked-by: Dmitry Torokhov <dtor@mail.ru> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Acked-by: Mauro Carvalho Chehab <mchehab@infradead.org> Acked-by: Pierre Ossman <drzeus-list@drzeus.cx> Cc: Jeff Garzik <jeff@garzik.org> Cc: "David S. Miller" <davem@davemloft.net> Acked-by: Greg KH <greg@kroah.com> Cc: James Bottomley <James.Bottomley@steeleye.com> Cc: "Antonino A. Daplas" <adaplas@pol.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-04-25[SK_BUFF]: Introduce skb_copy_from_linear_data{_offset}Arnaldo Carvalho de Melo
To clearly state the intent of copying from linear sk_buffs, _offset being a overly long variant but interesting for the sake of saving some bytes. Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2006-09-13drivers/net: Trim trailing whitespaceJeff Garzik
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2006-03-03Massive net driver const-ification.Arjan van de Ven
2006-01-10[PATCH] TTY layer buffering revampAlan Cox
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>
2005-07-08[NET]: Transform skb_queue_len() binary tests into skb_queue_empty()David S. Miller
This is part of the grand scheme to eliminate the qlen member of skb_queue_head, and subsequently remove the 'list' member of sk_buff. Most users of skb_queue_len() want to know if the queue is empty or not, and that's trivially done with skb_queue_empty() which doesn't use the skb_queue_head->qlen member and instead uses the queue list emptyness as the test. Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-23[PATCH] Convert users to tty_unregister_ldisc()Alexey Dobriyan
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>
2005-04-16Linux-2.6.12-rc2Linus Torvalds
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!