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2007-02-11[PATCH] uml: chan_user.h formatting fixesJeff Dike
Whitespace fixes and emacs comment removal. Signed-off-by: Jeff Dike <jdike@addtoit.com> Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-11[PATCH] uml: mostly const a structureJeff Dike
The chan_opts structure is mostly const, and needs no locking. Comment the lack of locking on the one field that can change. Make all the other fields const. It turned out that console_open_chan didn't use its chan_opts argument, so that is deleted from the function and its callers. Signed-off-by: Jeff Dike <jdike@addtoit.com> Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-11[PATCH] uml: locking commentary in the random driverJeff Dike
Comment the lack of locking. Signed-off-by: Jeff Dike <jdike@addtoit.com> Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-11[PATCH] uml: use LIST_HEAD where possibleJeff Dike
A couple of list_head declarations can be improved through the use of LIST_HEAD(). Signed-off-by: Jeff Dike <jdike@addtoit.com> Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-11[PATCH] uml: network driver locking and code cleanupJeff Dike
Add some missing locking to walks of the transports and opened lists. Delete some dead code. Comment the lack of some locking. Signed-off-by: Jeff Dike <jdike@addtoit.com> Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-11[PATCH] uml: Kill a compilation warningJeff Dike
Kill a compilation warning. Signed-off-by: Jeff Dike <jdike@addtoit.com> Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-11[PATCH] uml: port driver formattingJeff Dike
Whitespace and style fixes. Signed-off-by: Jeff Dike <jdike@addtoit.com> Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-11[PATCH] uml: make two variables staticJeff Dike
Make a couple of variables static. Signed-off-by: Jeff Dike <jdike@addtoit.com> Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-11[PATCH] uml: mconsole lockingJeff Dike
Locking fixes. Locking was totally lacking for the mconsole_devices, which got a spin lock, and the unplugged pages data, which got a mutex. The locking of the mconsole console output code was confused. Now, the console_lock (renamed to client_lock) protects the clients list. Signed-off-by: Jeff Dike <jdike@addtoit.com> Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-11[PATCH] uml: audio driver formattingJeff Dike
Whitespace and style fixes. Signed-off-by: Jeff Dike <jdike@addtoit.com> Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-11[PATCH] uml: audio driver lockingJeff Dike
Comment the lack of locking and make a couple of variables static. Signed-off-by: Jeff Dike <jdike@addtoit.com> Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-11[PATCH] uml: watchdog driver formattingJeff Dike
Whitespace and style fixes. Signed-off-by: Jeff Dike <jdike@addtoit.com> Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-11[PATCH] uml: watchdog driver lockingJeff Dike
Replace BKL use with a spinlock. Also fix the control so that open doesn't return holding a lock. Signed-off-by: Jeff Dike <jdike@addtoit.com> Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-11[PATCH] uml: network driver whitespace and style fixesJeff Dike
Some whitespace and coding style cleanups in the network driver code. Signed-off-by: Jeff Dike <jdike@addtoit.com> Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Acked-by: Jeff Garzik <jeff@garzik.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-11[PATCH] uml: add locking to network transport registrationJeff Dike
The registration of host network transports needed some locking. The transport list itself is locked, but calls to the registration routines are not. This is compensated for by checking that a transport structure is not yet on any list. I also took the opportunity to const all fields in the transport structure except the list, which obviously can be modified. Signed-off-by: Jeff Dike <jdike@addtoit.com> Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-11[PATCH] uml: lock the irqs_to_free listJeff Dike
Fix (i.e. add some) the locking around the irqs_to_free list. Signed-off-by: Jeff Dike <jdike@addtoit.com> Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-11[PATCH] uml: console whitespace and comment tidyingJeff Dike
Some comment and whitespace cleanups in the console and mconsole code. Signed-off-by: Jeff Dike <jdike@addtoit.com> Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-11[PATCH] uml: return hotplug errors to hostJeff Dike
I noticed that errors happening while hotplugging devices from the host were never returned back to the mconsole client. In some cases, success was returned instead of even an information-free error. This patch cleans that up by having the low-level configuration code pass back an error string along with an error code. At the top level, which knows whether it is early boot time or responding to an mconsole request, the string is printk'd or returned to the mconsole client. There are also whitespace and trivial code cleanups in the surrounding code. Signed-off-by: Jeff Dike <jdike@addtoit.com> Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-11[PATCH] uml: console locking fixesJeff Dike
Clean up the console driver locking. There are various problems here, including sleeping under a spinlock and spinlock recursion, some of which are fixed here. This patch deals with the locking involved with opens and closes. The problem is that an mconsole request to change a console's configuration can race with an open. Changing a configuration should only be done when a console isn't opened. Also, an open must be looking at a stable configuration. In addition, a get configuration request must observe the same locking since it must also see a stable configuration. With the old locking, it was possible for this to hang indefinitely in some cases because open would block for a long time waiting for a connection from the host while holding the lock needed by the mconsole request. As explained in the long comment, this is fixed by adding a spinlock for the use count and configuration and a mutex for the actual open and close. Signed-off-by: Jeff Dike <jdike@addtoit.com> Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-01-30[PATCH] uml: fix signal frame alignmentJeff Dike
Use the same signal frame alignment calculations as the underlying architecture. x86_64 appeared to do this, but the "- 8" was really subtracting 8 * sizeof(struct rt_sigframe) rather than 8 bytes. UML/i386 might have been OK, but I changed the calculation to match i386 just to be sure. Signed-off-by: Jeff Dike <jdike@addtoit.com> Cc: <stable@kernel.org> Cc: Adrian Bunk <bunk@stusta.de> Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Acked-by: Antoine Martin <antoine@nagafix.co.uk> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-01-30[PATCH] fix indentation-related breakage in Kconfig.i386Al Viro
Kconfig recognizes the end of help text by receding indentation depth. Recent patch had broken HOST_VMSPLIT_... choice in arch/um/Kconfig.i386 - all alternatives are interpreted as part of help text now. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-01-26[PATCH] Fix UML on non-standard VM split hostsJeff Dike
This fixes UML on hosts with non-standard VM splits. We had changed the config variable that controls UML behavior on such hosts, but not propogated the change everywhere. In particular, the values of STUB_CODE and STUB_DATA relied on the old variable. I also reformatted the HOST_VMSPLIT_3G help to make it more standard. Spotted by uml@flonatel.org. Signed-off-by: Jeff Dike <jdike@addtoit.com> Cc: Blaisorblade <blaisorblade@yahoo.it> Cc: Pravin <shindepravin@gmail.com> Cc: <uml@flonatel.org> Cc: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2006-12-13[PATCH] getting rid of all casts of k[cmz]alloc() callsRobert P. J. Day
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>
2006-12-13[PATCH] uml: fix net_kern workqueue abusePeter Zijlstra
Fix up the work on stack and exit scope trouble by placing the work_struct in the uml_net_private data. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: Jeff Dike <jdike@addtoit.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-12um: replace kmalloc+memset with kzallocYan Burman
Replace kmalloc+memset with kzalloc Signed-off-by: Yan Burman <burman.yan@gmail.com> Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-12-08[PATCH] tty: switch to ktermiosAlan Cox
This is the grungy swap all the occurrences in the right places patch that goes with the updates. At this point we have the same functionality as before (except that sgttyb() returns speeds not zero) and are ready to begin turning new stuff on providing nobody reports lots of bugs If you are a tty driver author converting an out of tree driver the only impact should be termios->ktermios name changes for the speed/property setting functions from your upper layers. If you are implementing your own TCGETS function before then your driver was broken already and its about to get a whole lot more painful for you so please fix it 8) Also fill in c_ispeed/ospeed on init for most devices, although the current code will do this for you anyway but I'd like eventually to lose that extra paranoia [akpm@osdl.org: bluetooth fix] [mp3@de.ibm.com: sclp fix] [mp3@de.ibm.com: warning fix for tty3270] [hugh@veritas.com: fix tty_ioctl powerpc build] [jdike@addtoit.com: uml: fix ->set_termios declaration] Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Martin Peschke <mp3@de.ibm.com> Acked-by: Peter Oberparleiter <oberpar@de.ibm.com> Cc: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Hugh Dickins <hugh@veritas.com> Signed-off-by: Jeff Dike <jdike@addtoit.com> Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-08[PATCH] UML: add generic BUG supportJeff Dike
The BUG changes in -mm3 need some arch support. This patch adds the UML support needed. For the most part, it was stolen from the underlying architecture. The exception is the kernel eip < PAGE_OFFSET test, which is wrong for skas mode UMLs. Signed-off-by: Jeff Dike <jdike@addtoit.com> Cc: Jeremy Fitzhardinge <jeremy@goop.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-08[PATCH] tty: ->signal->tty lockingPeter Zijlstra
Fix the locking of signal->tty. Use ->sighand->siglock to protect ->signal->tty; this lock is already used by most other members of ->signal/->sighand. And unless we are 'current' or the tasklist_lock is held we need ->siglock to access ->signal anyway. (NOTE: sys_unshare() is broken wrt ->sighand locking rules) Note that tty_mutex is held over tty destruction, so while holding tty_mutex any tty pointer remains valid. Otherwise the lifetime of ttys are governed by their open file handles. This leaves some holes for tty access from signal->tty (or any other non file related tty access). It solves the tty SLAB scribbles we were seeing. (NOTE: the change from group_send_sig_info to __group_send_sig_info needs to be examined by someone familiar with the security framework, I think it is safe given the SEND_SIG_PRIV from other __group_send_sig_info invocations) [schwidefsky@de.ibm.com: 3270 fix] [akpm@osdl.org: various post-viro fixes] Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: Alan Cox <alan@redhat.com> Cc: Oleg Nesterov <oleg@tv-sign.ru> Cc: Prarit Bhargava <prarit@redhat.com> Cc: Chris Wright <chrisw@sous-sol.org> Cc: Roland McGrath <roland@redhat.com> Cc: Stephen Smalley <sds@tycho.nsa.gov> Cc: James Morris <jmorris@namei.org> Cc: "David S. Miller" <davem@davemloft.net> Cc: Jeff Dike <jdike@addtoit.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Jan Kara <jack@ucw.cz> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-07[PATCH] uml: use get_random_bytes() after random pool is seededJeff Dike
When the UML network driver generates random MACs for its devices, it was possible for a number of UMLs to get the same MACs because the ethernet initialization was done before the random pool was properly seeded. This patch moves the initialization later so that it gets better randomness. Signed-off-by: Jeff Dike <jdike@addtoit.com> Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-07[PATCH] uml: size register files correctlyJeff Dike
We were using the wrong symbol to size register files. Signed-off-by: Jeff Dike <jdike@addtoit.com> Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-07[PATCH] uml: include asm/page.h in order to get PAGE_SHIFTJeff Dike
Include the proper header to get a definition of PAGE_SHIFT. Signed-off-by: Jeff Dike <jdike@addtoit.com> Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-07[PATCH] uml: include stddef.h correctlyJeff Dike
We were not including stddef.h in files that used offsetof. One file was also including linux/stddef.h for no perciptible reason. Signed-off-by: Jeff Dike <jdike@addtoit.com> Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-07[PATCH] uml: workqueue build fixAndrew Morton
arch/um/drivers/chan_kern.c:643: error: conflicting types for 'chan_interrupt' arch/um/include/chan_kern.h:31: error: previous declaration of 'chan_interrupt' Cc: David Howells <dhowells@redhat.com> Cc: Jeff Dike <jdike@addtoit.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-05WorkQueue: Fix up arch-specific work items where possibleDavid Howells
Fix up arch-specific work items where possible to use the new work_struct and delayed_work structs. Three places that enqueue bits of their stack and then return have been marked with #error as this is not permitted. Signed-Off-By: David Howells <dhowells@redhat.com>
2006-12-02[NET]: UML checksum annotations and cleanups.Al Viro
* sanitize prototypes, annotate * kill csum_partial_copy_fromuser * kill shift-by-16 in checksum calculations * ntohs->shift in checksum calculations Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-11-30Fix typos in doc and commentsJan Engelhardt
Changes persistant -> persistent. www.dictionary.com does not know persistant (with an A), but should it be one of those things you can spell in more than one correct way, let me know. Signed-off-by: Jan Engelhardt <jengelh@gmx.de> Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-11-25[PATCH] uml: make execvp safe for our usagePaolo 'Blaisorblade' Giarrusso
Reimplement execvp for our purposes - after we call fork() it is fundamentally unsafe to use the kernel allocator - current is not valid there. So we simply pass to our modified execvp() a preallocated buffer. This fixes a real bug and works very well in testing (I've seen indirectly warning messages from the forked thread - they went on the pipe connected to its stdout and where read as a number by UML, when calling read_output(). I verified the obtained number corresponded to "BUG:"). The added use of __cant_sleep() is not a new bug since __cant_sleep() is already used in the same function - passing an atomicity parameter would be better but it would require huge change, stating that this function must not be called in atomic context and can sleep is a better idea (will make sure of this gradually). Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Acked-by: Jeff Dike <jdike@addtoit.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-11-03[PATCH] uml: include tidyingJeff Dike
In order to get the __NR_* constants, we need sys/syscall.h. linux/unistd.h works as well since it includes syscall.h, however syscall.h is more parsimonious. We were inconsistent in this, and this patch adds syscall.h includes where necessary and removes linux/unistd.h includes where they are not needed. asm/unistd.h also includes the __NR_* constants, but these are not the glibc-sanctioned ones, so this also removes one such inclusion. Signed-off-by: Jeff Dike <jdike@addtoit.com> Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-11-03[PATCH] uml: fix I/O hangJeff Dike
Fix a UML hang in which everything would just stop until some I/O happened - a ping, someone whacking the keyboard - at which point everything would start up again as though nothing had happened. The cause was gcc reordering some code which absolutely needed to be executed in the order in the source. When unblock_signals switches signals from off to on, it needs to see if any interrupts had happened in the critical section. The interrupt handlers check signals_enabled - if it is zero, then the handler adds a bit to the "pending" bitmask and returns. unblock_signals checks this mask to see if any signals need to be delivered. The crucial part is this: signals_enabled = 1; save_pending = pending; if(save_pending == 0) return; pending = 0; In order to avoid an interrupt arriving between reading pending and setting it to zero, in which case, the record of the interrupt would be erased, signals are enabled. What happened was that gcc reordered this so that 'save_pending = pending' came before 'signals_enabled = 1', creating a one-instruction window within which an interrupt could arrive, set its bit in pending, and have it be immediately erased. When the I/O workload is purely disk-based, the loss of a block device interrupt stops the entire I/O system because the next block request will wait for the current one to finish. Thus the system hangs until something else causes some I/O to arrive, such as a network packet or console input. The fix to this particular problem is a memory barrier between enabling signals and reading the pending signal mask. An xchg would also probably work. Looking over this code for similar problems led me to do a few more things: - make signals_enabled and pending volatile so that they don't get cached in registers - add an mb() to the return paths of block_signals and unblock_signals so that the modification of signals_enabled doesn't get shuffled into the caller in the event that these are inlined in the future. Signed-off-by: Jeff Dike <jdike@addtoit.com> Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-31[PATCH] uml: add _text definition to linker scriptsJeff Dike
kallsyms now refers to addresses as '_text + 0xADDRESS', rather than just '0xADDRESS', so we need to define _text. Signed-off-by: Jeff Dike <jdike@addtoit.com> Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-31[PATCH] uml ubd driver: various little changesPaolo 'Blaisorblade' Giarrusso
Fix a small memory leak in ubd_config, and clearify the confusion which lead to it. Then, some little changes not affecting operations - * move init functions together, * add a comment about a potential problem in case of some evolution in the block layer, * mark all initcalls as static __init functions * mark an used once little function as inline * document that mconsole methods are all called in process context (was triggered when checking ubd mconsole methods). Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Cc: Jeff Dike <jdike@addtoit.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-31[PATCH] uml ubd driver: do not store error codes as ->fdPaolo 'Blaisorblade' Giarrusso
To simplify error handling, make sure fd is saved into ubd_dev->fd only when we are sure it is an fd and not an error code. Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Cc: Jeff Dike <jdike@addtoit.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-31[PATCH] uml ubd driver: use bitfields where possiblePaolo 'Blaisorblade' Giarrusso
Use bitfields for boolean fields in ubd data structure. Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Cc: Jeff Dike <jdike@addtoit.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-31[PATCH] uml ubd driver: reformat ubd_configPaolo 'Blaisorblade' Giarrusso
Pure whitespace and style fixes split out from subsequent patch. Some changes (err -> ret) don't make sense now, only later, but I split them out anyway since they cluttered the patch. Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Cc: Jeff Dike <jdike@addtoit.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-31[PATCH] uml ubd driver: convert do_ubd to a boolean variablePaolo 'Blaisorblade' Giarrusso
do_ubd is actually just a boolean variable - the way it is used currently is a leftover from the old 2.4 block layer, but it is still used; its use is suspicious, but removing it would be too intrusive for now and needs more thinking. Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Cc: Jeff Dike <jdike@addtoit.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-31[PATCH] uml ubd driver: ubd_io_lock usage fixupPaolo 'Blaisorblade' Giarrusso
Add some comments about requirements for ubd_io_lock and expand its use. When an irq signals that the "controller" (i.e. another thread on the host, which does the actual requests and is the only one blocked on I/O on the host) has done some work, we call again the request function ourselves (do_ubd_request). We now do that with ubd_io_lock held - that's useful to protect against concurrent calls to elv_next_request and so on. XXX: Maybe we shouldn't call at all the request function. Input needed on this. Are we supposed to plug and unplug the queue? That code "indirectly" does that by setting a flag, called do_ubd, which makes the request function return (it's a residual of 2.4 block layer interface). Meanwhile, however, merge this patch, which improves things. Cc: Jens Axboe <axboe@suse.de> Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Cc: Jeff Dike <jdike@addtoit.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-31[PATCH] uml ubd driver: change ubd_lock to be a mutexPaolo 'Blaisorblade' Giarrusso
This lock protects ubd setup and teardown, so is only used in process context; beyond that, during such setup memory allocations must be performed and some generic functions which can sleep must be called (such as add_disk()). So the only correct solution is to make it a mutex instead of a spin_lock. No other change is done - this lock must be acquired in different places but it's done afterwards. Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Cc: Jeff Dike <jdike@addtoit.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-31[PATCH] uml ubd driver: give better names to some functions.Paolo 'Blaisorblade' Giarrusso
To rethink locking, I needed to understand well what each function does. While doing this I renamed some: * ubd_close -> ubd_close_dev (since it pairs with ubd_open_dev) * ubd_new_disk -> ubd_disk_register (it handles registration with the block layer - one hopes this makes clearer the difference with ubd_add()) Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Cc: Jeff Dike <jdike@addtoit.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-31[PATCH] uml ubd driver: var renamesPaolo 'Blaisorblade' Giarrusso
Rename the ubd_dev array to ubd_devs and then call any "struct ubd" ubd_dev instead of dev, which doesn't make clear what we're treating (and no, it's not hungarian notation - not any more than calling all vm_area_struct vma or all inodes inode). Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Cc: Jeff Dike <jdike@addtoit.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-31[PATCH] uml ubd driver: document some struct fieldsPaolo 'Blaisorblade' Giarrusso
Add documentation about some fields in struct ubd, whose meaning is non-obvious due to struct names (should change names altogether, I agree). Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Cc: Jeff Dike <jdike@addtoit.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>