summaryrefslogtreecommitdiffstats
path: root/arch/s390/lib
AgeCommit message (Collapse)AuthorFilesLines
2011-05-26[S390] delay: implement ndelayHeiko Carstens1-0/+15
Implement ndelay() on s390 as well. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2011-03-11futex: Sanitize futex ops argument typesMichel Lespinasse3-13/+13
Change futex_atomic_op_inuser and futex_atomic_cmpxchg_inatomic prototypes to use u32 types for the futex as this is the data type the futex core code uses all over the place. Signed-off-by: Michel Lespinasse <walken@google.com> Cc: Darren Hart <darren@dvhart.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Matt Turner <mattst88@gmail.com> Cc: Russell King <linux@arm.linux.org.uk> Cc: David Howells <dhowells@redhat.com> Cc: Tony Luck <tony.luck@intel.com> Cc: Michal Simek <monstr@monstr.eu> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: "James E.J. Bottomley" <jejb@parisc-linux.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Paul Mundt <lethal@linux-sh.org> Cc: "David S. Miller" <davem@davemloft.net> Cc: Chris Metcalf <cmetcalf@tilera.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> LKML-Reference: <20110311025058.GD26122@google.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-03-11futex: Sanitize cmpxchg_futex_value_locked APIMichel Lespinasse3-9/+14
The cmpxchg_futex_value_locked API was funny in that it returned either the original, user-exposed futex value OR an error code such as -EFAULT. This was confusing at best, and could be a source of livelocks in places that retry the cmpxchg_futex_value_locked after trying to fix the issue by running fault_in_user_writeable(). This change makes the cmpxchg_futex_value_locked API more similar to the get_futex_value_locked one, returning an error code and updating the original value through a reference argument. Signed-off-by: Michel Lespinasse <walken@google.com> Acked-by: Chris Metcalf <cmetcalf@tilera.com> [tile] Acked-by: Tony Luck <tony.luck@intel.com> [ia64] Acked-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Michal Simek <monstr@monstr.eu> [microblaze] Acked-by: David Howells <dhowells@redhat.com> [frv] Cc: Darren Hart <darren@dvhart.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Matt Turner <mattst88@gmail.com> Cc: Russell King <linux@arm.linux.org.uk> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: "James E.J. Bottomley" <jejb@parisc-linux.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Paul Mundt <lethal@linux-sh.org> Cc: "David S. Miller" <davem@davemloft.net> Cc: Linus Torvalds <torvalds@linux-foundation.org> LKML-Reference: <20110311024851.GC26122@google.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-01-31[S390] missing sacf in uaccessMartin Schwidefsky1-6/+4
The uaccess functions copy_in_user_std and clear_user_std fail to switch back from secondary space mode to primary space mode with sacf in case of an unresolvable page fault. We need to make sure that the switch back to primary mode is done in all cases, otherwise the code following the uaccess inline assembly will crash. Reported-by: Alexander Graf <agraf@suse.de> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2011-01-05[S390] time: let local_tick_enable/disable() reprogram the clock comparatorHeiko Carstens1-2/+0
Let local_tick_enable/disable() reprogram the clock comparator so the function names make semantically more sense. Also that way the functions are more symmetric since normally each local_tick_enable() call usually would have a subsequent call to set_clock_comparator() anyway. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2010-11-25[S390] nmi: fix clock comparator revalidationHeiko Carstens1-5/+9
On each machine check all registers are revalidated. The save area for the clock comparator however only contains the upper most seven bytes of the former contents, if valid. Therefore the machine check handler uses a store clock instruction to get the current time and writes that to the clock comparator register which in turn will generate an immediate timer interrupt. However within the lowcore the expected time of the next timer interrupt is stored. If the interrupt happens before that time the handler won't be called. In turn the clock comparator won't be reprogrammed and therefore the interrupt condition stays pending which causes an interrupt loop until the expected time is reached. On NOHZ machines this can result in unresponsive machines since the time of the next expected interrupted can be a couple of days in the future. To fix this just revalidate the clock comparator register with the expected value. In addition the special handling for udelay must be changed as well. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2010-03-08[S390] uaccess: make sure copy_from_user_overflow is builtinHeiko Carstens1-1/+2
If there is no in kernel image caller modules will suffer: ERROR: "copy_from_user_overflow" [net/core/pktgen.ko] undefined! ERROR: "copy_from_user_overflow" [net/can/can-raw.ko] undefined! ERROR: "copy_from_user_overflow" [fs/cifs/cifs.ko] undefined! Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2010-02-26[S390] spinlock: check virtual cpu running statusGerald Schaefer1-16/+37
This patch introduces a new function that checks the running status of a cpu in a hypervisor. This status is not virtualized, so the check is only correct if running in an LPAR. On acquiring a spinlock, if the cpu holding the lock is scheduled by the hypervisor, we do a busy wait on the lock. If it is not scheduled, we yield over to that cpu. Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2010-02-26[S390] uaccess: implement strict user copy checksHeiko Carstens2-1/+9
Same as on x86 and sparc, besides the fact that enabling the option will just emit compile time warnings instead of errors. Keeps allyesconfig kernels compiling. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2010-01-13[S390] Move __cpu_logical_map to smp.cHeiko Carstens1-1/+1
Finally move it to the place where it belongs to and make get rid of it for !CONFIG_SMP. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-12-14locking: Convert raw_rwlock functions to arch_rwlockThomas Gleixner1-6/+6
Name space cleanup for rwlock functions. No functional change. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra <peterz@infradead.org> Acked-by: David S. Miller <davem@davemloft.net> Acked-by: Ingo Molnar <mingo@elte.hu> Cc: linux-arch@vger.kernel.org
2009-12-14locking: Convert raw_rwlock to arch_rwlockThomas Gleixner1-6/+6
Not strictly necessary for -rt as -rt does not have non sleeping rwlocks, but it's odd to not have a consistent naming convention. No functional change. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra <peterz@infradead.org> Acked-by: David S. Miller <davem@davemloft.net> Acked-by: Ingo Molnar <mingo@elte.hu> Cc: linux-arch@vger.kernel.org
2009-12-14locking: Convert __raw_spin* functions to arch_spin*Thomas Gleixner1-11/+11
Name space cleanup. No functional change. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra <peterz@infradead.org> Acked-by: David S. Miller <davem@davemloft.net> Acked-by: Ingo Molnar <mingo@elte.hu> Cc: linux-arch@vger.kernel.org
2009-12-14locking: Convert raw_spinlock to arch_spinlockThomas Gleixner1-4/+4
The raw_spin* namespace was taken by lockdep for the architecture specific implementations. raw_spin_* would be the ideal name space for the spinlocks which are not converted to sleeping locks in preempt-rt. Linus suggested to convert the raw_ to arch_ locks and cleanup the name space instead of using an artifical name like core_spin, atomic_spin or whatever No functional change. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra <peterz@infradead.org> Acked-by: David S. Miller <davem@davemloft.net> Acked-by: Ingo Molnar <mingo@elte.hu> Cc: linux-arch@vger.kernel.org
2009-12-07[S390] Use do_exception() in pagetable walk usercopy functions.Gerald Schaefer1-96/+51
The pagetable walk usercopy functions have used a modified copy of the do_exception() function for fault handling. This lead to inconsistencies with recent changes to do_exception(), e.g. performance counters. This patch changes the pagetable walk usercopy code to call do_exception() directly, eliminating the redundancy. A new parameter is added to do_exception() to specify the fault address. Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-12-07[S390] Improve address space mode selection.Martin Schwidefsky1-4/+0
Introduce user_mode to replace the two variables switch_amode and s390_noexec. There are three valid combinations of the old values: 1) switch_amode == 0 && s390_noexec == 0 2) switch_amode == 1 && s390_noexec == 0 3) switch_amode == 1 && s390_noexec == 1 They get replaced by 1) user_mode == HOME_SPACE_MODE 2) user_mode == PRIMARY_SPACE_MODE 3) user_mode == SECONDARY_SPACE_MODE The new kernel parameter user_mode=[primary,secondary,home] lets you choose the address space mode the user space processes should use. In addition the CONFIG_S390_SWITCH_AMODE config option is removed. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-10-06[S390] Add EX_TABLE for addressing exception in usercopy functions.Gerald Schaefer2-12/+14
This patch adds an EX_TABLE entry to mvc{p|s|os} usercopy functions that may be called with KERNEL_DS. In combination with collaborative memory management, kernel pages marked as unused may trigger an adressing exception in the usercopy functions. This fixes an unhandled addressing exception bug where strncpy_from_user() is used with len > strnlen and KERNEL_DS, crossing a page boundary to an unused page. Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-10-06[S390] Provide arch specific mdelay implementation.Heiko Carstens1-7/+7
Use an own implementation instead of the common code udelay loop. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-10-06[S390] Fix enabled udelay for short delays.Christian Borntraeger1-4/+9
When udelay() gets called with a delay that would expire before the next clock event it reprograms the clock comparator. When the interrupt happens the clock comparator won't be resetted therefore the interrupt condition doesn't get cleared. The result is an endless timer interrupt loop until the next clock event would expire (stored in lowcore). So udelay() usually would wait much longer for small delays than it should. Fix this by disabling the local tick which makes sure that the clock comparator will be resetted when a timer interrupt happens. Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-07-07[S390] add __ucmpdi2() helper functionHeiko Carstens2-1/+27
Provide __ucmpdi2() helper function on 31 bit so we don't run again and again in compile errors like this one: kernel/built-in.o: In function `T.689': perf_counter.c:(.text+0x56c86): undefined reference to `__ucmpdi2' Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-07-07[S390] udelay: disable lockdep to avoid false positivesHeiko Carstens1-0/+2
Our udelay implementation enables interrupts to receive a special timer interrupt regardless of the context it is called from. This might lead to false positive lockdep reports. Since lockdep isn't aware of the fact that only a single interrupt source is enabled it warns about possible deadlocks that in reality won't happen, like the one below. To fix this disable lockdep before enabling interrupts. [ 254.040888] ================================= [ 254.040904] [ INFO: inconsistent lock state ] [ 254.040910] 2.6.30 #9 [ 254.040914] --------------------------------- [ 254.040920] inconsistent {IN-HARDIRQ-W} -> {HARDIRQ-ON-W} usage. [ 254.040927] swapper/0 [HC0[0]:SC1[1]:HE1:SE0] takes: [ 254.040934] (sch->lock){?.-...}, at: [<00000000002e4778>] ccw_device_timeout+0x48/0x2f0 [ 254.040961] {IN-HARDIRQ-W} state was registered at: [ 254.040969] [<0000000000096f74>] __lock_acquire+0x9d4/0x188c [ 254.040985] [<0000000000097f68>] lock_acquire+0x13c/0x16c [ 254.040998] [<00000000004527e0>] _spin_lock+0x74/0xb8 [ 254.041016] [<0000000000457eb2>] do_IRQ+0xde/0x208 [ 254.041031] [<000000000002d190>] io_return+0x0/0x8 [ 254.041049] [<0000000000029faa>] vtime_stop_cpu+0xbe/0x114 [ 254.041066] irq event stamp: 259629 [ 254.041076] hardirqs last enabled at (259628): [<000000000045238e>] _spin_unlock_irq+0x5e/0x9c [ 254.041095] hardirqs last disabled at (259629): [<000000000045292e>] _spin_lock_irq+0x4a/0xc4 [ 254.041126] softirqs last enabled at (259614): [<000000000006500e>] __do_softirq+0x296/0x2b0 [ 254.041137] softirqs last disabled at (259619): [<0000000000024cf6>] do_softirq+0x102/0x108 [ 254.041147] [ 254.041148] other info that might help us debug this: [ 254.041153] 2 locks held by swapper/0: [ 254.041157] #0: (&priv->timer){+.-...}, at: [<000000000006bf9a>] run_timer_softirq+0x19a/0x340 [ 254.041170] #1: (sch->lock){?.-...}, at: [<00000000002e4778>] ccw_device_timeout+0x48/0x2f0 [ 254.041182] [ 254.041310] Call Trace: [ 254.041313] ([<00000000000174fc>] show_trace+0x16c/0x170) [ 254.041321] [<0000000000017578>] show_stack+0x78/0x104 [ 254.041327] [<000000000044d0ca>] dump_stack+0xc6/0xd4 [ 254.041342] [<00000000000949b4>] print_usage_bug+0x1c8/0x1fc [ 254.041353] [<0000000000094e8a>] mark_lock+0x4a2/0x670 [ 254.041364] [<00000000000950e2>] mark_held_locks+0x8a/0xb4 [ 254.041375] [<0000000000095398>] trace_hardirqs_on_caller+0x74/0x1ac [ 254.041388] [<00000000000954fa>] trace_hardirqs_on+0x2a/0x38 [ 254.041402] [<000000000025f1ec>] __udelay_disabled+0xac/0xfc [ 254.041419] [<000000000025f432>] __udelay+0x12a/0x148 [ 254.041433] [<00000000002d64d8>] cio_commit_config+0x170/0x290 [ 254.041451] [<00000000002d6978>] cio_disable_subchannel+0x120/0x1cc [ 254.041468] [<00000000002e32a4>] ccw_device_recog_done+0x54/0x2f4 [ 254.041485] [<00000000002e3638>] ccw_device_sense_id_done+0x50/0x90 [ 254.041508] [<00000000002e615a>] snsid_callback+0xfa/0x3a8 [ 254.041515] [<00000000002dd96c>] ccwreq_stop+0x80/0x90 [ 254.041523] [<00000000002dda8e>] ccw_request_timeout+0xc2/0xd0 [ 254.041530] [<00000000002e2f70>] ccw_device_request_event+0x58/0x90 [ 254.041537] [<00000000002e47ae>] ccw_device_timeout+0x7e/0x2f0 [ 254.041555] [<000000000006c02a>] run_timer_softirq+0x22a/0x340 [ 254.041566] [<0000000000064eb0>] __do_softirq+0x138/0x2b0 [ 254.041578] [<0000000000024cf6>] do_softirq+0x102/0x108 [ 254.041590] [<00000000000647ce>] irq_exit+0xee/0x114 [ 254.041603] [<0000000000457d88>] do_extint+0x130/0x17c [ 254.041617] [<000000000002d41e>] ext_no_vtime+0x1e/0x22 [ 254.041631] [<0000000000029faa>] vtime_stop_cpu+0xbe/0x114 [ 254.041646] ([<0000000000029f58>] vtime_stop_cpu+0x6c/0x114) [ 254.041662] [<000000000001d842>] cpu_idle+0x122/0x1c0 [ 254.041679] [<00000000004482c6>] start_secondary+0xce/0xe0 [ 254.041696] [<0000000000000000>] 0x0 [ 254.041715] [<0000000000000000>] 0x0 [ 254.041745] INFO: lockdep is turned off. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-06-21Move FAULT_FLAG_xyz into handle_mm_fault() callersLinus Torvalds1-1/+1
This allows the callers to now pass down the full set of FAULT_FLAG_xyz flags to handle_mm_fault(). All callers have been (mechanically) converted to the new calling convention, there's almost certainly room for architectures to clean up their code and then add FAULT_FLAG_RETRY when that support is added. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-12[S390] implement interrupt-enabling rwlocksHeiko Carstens1-0/+40
arch backend for f5f7eac41db827a47b2163330eecd7bb55ae9f12 "Allow rwlocks to re-enable interrupts". Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-26[S390] use compiler builtin versions of strlen/strcpy/strcatHeiko Carstens1-0/+8
Use builtin variants if gcc 4 or newer is used to compile the kernel. Generates better code than the asm variants. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-26[S390] move EXPORT_SYMBOLs to definitionsHeiko Carstens1-0/+2
Move all EXPORT_SYMBOLs to their corresponding definitions. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-18[S390] Dont check for pfn_valid() in uaccess_pt.cGerald Schaefer1-18/+0
pfn_valid() actually checks for a valid struct page and not for a valid pfn. Using xip mappings w/o struct pages, this will result in -EFAULT returned by the (page table walk) user copy functions, even though there is valid memory. Those user copy functions don't need a struct page, so this patch just removes the pfn_valid() check. Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-18[S390] __div64_31 broken for CONFIG_MARCH_G5Martin Schwidefsky1-1/+1
The implementation of __div64_31 for G5 machines is broken. The comments in __div64_31 are correct, only the code does not do what the comments say. The part "If the remainder has overflown subtract base and increase the quotient" is only partially realized, the base is subtracted correctly but the quotient is only increased if the dividend had the last bit set. Using the correct instruction fixes the problem. Cc: stable@kernel.org Reported-by: Frans Pop <elendil@planet.nl> Tested-by: Frans Pop <elendil@planet.nl> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-10-10[S390] Move private simple udelay function to arch/s390/lib/delay.c.Heiko Carstens1-0/+13
Move cio's private simple udelay function to lib/delay.c and turn it into something much more readable. So we have all implementations at one place. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-10-03[S390] nohz: Fix __udelay.Heiko Carstens1-34/+54
This fixes a regression that came with 934b2857cc576ae53c92a66e63fce7ddcfa74691 ("[S390] nohz/sclp: disable timer on synchronous waits."). If udelay() gets called from a disabled context it sets the clock comparator to a value where it expects the next interrupt. When the interrupt happens the clock comparator gets not reset and therefore the interrupt condition doesn't get cleared. The result is an endless timer interrupt loop. In addition this patch fixes also the following: rcutorture reveals that our __udelay implementation is still buggy, since it might schedule tasklets, but prevents their execution: NOHZ: local_softirq_pending 42 NOHZ: local_softirq_pending 02 NOHZ: local_softirq_pending 142 NOHZ: local_softirq_pending 02 To fix this we make sure that only the clock comparator interrupt is enabled when the enabled wait psw is loaded. Also no code gets called anymore which might schedule tasklets. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-08-01[S390] nohz/sclp: disable timer on synchronous waits.Heiko Carstens1-2/+2
sclp_sync_wait wait synchronously for an sclp interrupt and disables timer interrupts. However on the irq enter paths there is an extra check if a timer interrupt would be due and calls the timer callback. This would schedule softirqs in the wrong context. So introduce local_tick_enable/disable which prevents this. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-04-30[S390] uaccess_mvcos: #ifdef config dependent code.Heiko Carstens1-0/+2
arch/s390/lib/uaccess_mvcos.c:166: warning: 'strnlen_user_mvcos' defined but not used arch/s390/lib/uaccess_mvcos.c:186: warning: 'strncpy_from_user_mvcos' defined but not used Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-04-30[S390] remove -traditionalMathieu Desnoyers1-2/+0
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca> CC: Sam Ravnborg <sam@ravnborg.org> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-04-17[S390] uaccess: Always access the correct address space.Heiko Carstens1-18/+41
The current uaccess page table walk code assumes at a few places that any access is a user space access. This is not correct if somebody has issued a set_fs(KERNEL_DS) in advance. Add code which checks which address space we are in and with this make sure we access the correct address space. This way we get also rid of the dirty if (!currrent-mm) return -EFAULT; hack in futex_atomic_cmpxchg_pt. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2008-04-17[S390] Convert s390 to GENERIC_CLOCKEVENTS.Heiko Carstens1-7/+7
This way we get rid of s390's NO_IDLE_HZ and use the generic dynticks variant instead. In addition we get high resolution timers for free. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2008-03-20[S390] futex: let futex_atomic_cmpxchg_pt survive early functional tests.Heiko Carstens1-0/+2
a0c1e9073ef7428a14309cba010633a6cd6719ea "futex: runtime enable pi and robust functionality" introduces a test wether futex in atomic stuff works or not. It does that by writing to address 0 of the kernel address space. This will crash on older machines where addressing mode switching is enabled but where the mvcos instruction is not available. Page table walking is done by hand and therefore the code tries to access current->mm which is NULL. Therefore add an extra check, so we survive the early test. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-02-19[S390] Fix futex_atomic_cmpxchg_std inline assembly.Heiko Carstens1-4/+4
Add missing exception table entry so that the kernel can handle proctection exceptions as well on the cs instruction. Currently only specification exceptions are handled correctly. The missing entry allows user space to crash the kernel. Cc: stable <stable@kernel.org> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-01-26[S390] do local_irq_restore while spinning in spin_lock_irqsave.Hisashi Hifumi1-0/+23
In s390's spin_lock_irqsave, interrupts remain disabled while spinning. In other architectures like x86 and powerpc, interrupts are re-enabled while spinning if IRQ is not masked before spin_lock_irqsave is called. The following patch re-enables interrupts through local_irq_restore while spinning for a lock acquisition. This can improve system response. [heiko.carstens@de.ibm.com: removed saving of pc] Signed-off-by: Hisashi Hifumi <hifumi.hisashi@oss.ntt.co.jp> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-01-26[S390] Remove owner_pc member from raw_spinlock_t.Heiko Carstens1-8/+4
Used to contain the address of the holder of the lock. But since the spinlock code is not inlined anymore all locks contain the same address anyway. And since in addtition nobody complained about that for ages its obviously unused. So remove it. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2007-10-22[S390] 4level-fixup cleanupMartin Schwidefsky1-1/+6
Get independent from asm-generic/4level-fixup.h Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2007-10-22[S390] Introduce follow_table in uaccess_pt.cMartin Schwidefsky1-63/+22
Define and use follow_table inline in uaccess_pt.c to simplify the code. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2007-10-19pid namespaces: define is_global_init() and is_container_init()Serge E. Hallyn1-1/+1
is_init() is an ambiguous name for the pid==1 check. Split it into is_global_init() and is_container_init(). A cgroup init has it's tsk->pid == 1. A global init also has it's tsk->pid == 1 and it's active pid namespace is the init_pid_ns. But rather than check the active pid namespace, compare the task structure with 'init_pid_ns.child_reaper', which is initialized during boot to the /sbin/init process and never changes. Changelog: 2.6.22-rc4-mm2-pidns1: - Use 'init_pid_ns.child_reaper' to determine if a given task is the global init (/sbin/init) process. This would improve performance and remove dependence on the task_pid(). 2.6.21-mm2-pidns2: - [Sukadev Bhattiprolu] Changed is_container_init() calls in {powerpc, ppc,avr32}/traps.c for the _exception() call to is_global_init(). This way, we kill only the cgroup if the cgroup's init has a bug rather than force a kernel panic. [akpm@linux-foundation.org: fix comment] [sukadev@us.ibm.com: Use is_global_init() in arch/m32r/mm/fault.c] [bunk@stusta.de: kernel/pid.c: remove unused exports] [sukadev@us.ibm.com: Fix capability.c to work with threaded init] Signed-off-by: Serge E. Hallyn <serue@us.ibm.com> Signed-off-by: Sukadev Bhattiprolu <sukadev@us.ibm.com> Acked-by: Pavel Emelianov <xemul@openvz.org> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Cedric Le Goater <clg@fr.ibm.com> Cc: Dave Hansen <haveblue@us.ibm.com> Cc: Herbert Poetzel <herbert@13thfloor.at> Cc: Kirill Korotaev <dev@sw.ru> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-19mm: fault feedback #2Nick Piggin1-12/+11
This patch completes Linus's wish that the fault return codes be made into bit flags, which I agree makes everything nicer. This requires requires all handle_mm_fault callers to be modified (possibly the modifications should go further and do things like fault accounting in handle_mm_fault -- however that would be for another patch). [akpm@linux-foundation.org: fix alpha build] [akpm@linux-foundation.org: fix s390 build] [akpm@linux-foundation.org: fix sparc build] [akpm@linux-foundation.org: fix sparc64 build] [akpm@linux-foundation.org: fix ia64 build] Signed-off-by: Nick Piggin <npiggin@suse.de> Cc: Richard Henderson <rth@twiddle.net> Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru> Cc: Russell King <rmk@arm.linux.org.uk> Cc: Ian Molton <spyro@f2s.com> Cc: Bryan Wu <bryan.wu@analog.com> Cc: Mikael Starvik <starvik@axis.com> Cc: David Howells <dhowells@redhat.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Cc: "Luck, Tony" <tony.luck@intel.com> Cc: Hirokazu Takata <takata@linux-m32r.org> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Roman Zippel <zippel@linux-m68k.org> Cc: Greg Ungerer <gerg@uclinux.org> Cc: Matthew Wilcox <willy@debian.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Paul Mundt <lethal@linux-sh.org> Cc: Kazumoto Kojima <kkojima@rr.iij4u.or.jp> Cc: Richard Curnow <rc@rc0.org.uk> Cc: William Lee Irwin III <wli@holomorphy.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Jeff Dike <jdike@addtoit.com> Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Cc: Miles Bader <uclinux-v850@lsi.nec.co.jp> Cc: Chris Zankel <chris@zankel.net> Acked-by: Kyle McMartin <kyle@mcmartin.ca> Acked-by: Haavard Skinnemoen <hskinnemoen@atmel.com> Acked-by: Ralf Baechle <ralf@linux-mips.org> Acked-by: Andi Kleen <ak@muc.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> [ Still apparently needs some ARM and PPC loving - Linus ] Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-10[S390] Bogomips calculation for 64 bit.Martin Schwidefsky1-2/+2
The bogomips calculation triggered via reading from /proc/cpuinfo can return incorrect values if the qrnnd assembly is called with a pointer in %r2 with any of the upper 32 bits set. Fix this by using 64 bit division / remainder operation provided by gcc instead of calling the assembly. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2007-04-25[S390]: Fix build on 31-bit.David S. Miller2-3/+1
Allow s390 to properly override the generic __div64_32() implementation by: 1) Using obj-y for div64.o in s390's makefile instead of lib-y 2) Adding the weak attribute to the generic implementation. Signed-off-by: David S. Miller <davem@davemloft.net>
2007-02-21[S390] prevent softirqs if delay is called disabledMartin Schwidefsky1-0/+7
The new delay implementation uses the clock comparator and an external interrupt even if it is called disabled for interrupts. To do this all external interrupt source except clock comparator are switched of before enabling external interrupts. The external interrupt at the end of the delay period may not execute softirqs or we can end up in a dead-lock. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2007-02-05[S390] Avoid excessive inlining.Heiko Carstens1-5/+5
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2007-02-05[S390] Calibrate delay and bogomips.Martin Schwidefsky2-1/+78
Preset the bogomips number to the cpu capacity value reported by store system information in SYSIB 1.2.2. This value is constant for a particular machine model and can be used to determine relative performance differences between machines. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2007-02-05[S390] ETR support.Martin Schwidefsky1-14/+34
This patch adds support for clock synchronization to an external time reference (ETR). The external time reference sends an oscillator signal and a synchronization signal every 2^20 microseconds to keep the TOD clocks of all connected servers in sync. For availability two ETR units can be connected to a machine. If the clock deviates for more than the sync-check tolerance all cpus get a machine check that indicates that the clock is out of sync. For the lovely details how to get the clock back in sync see the code below. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2007-02-05[S390] noexec protectionGerald Schaefer2-1/+372
This provides a noexec protection on s390 hardware. Our hardware does not have any bits left in the pte for a hw noexec bit, so this is a different approach using shadow page tables and a special addressing mode that allows separate address spaces for code and data. As a special feature of our "secondary-space" addressing mode, separate page tables can be specified for the translation of data addresses (storage operands) and instruction addresses. The shadow page table is used for the instruction addresses and the standard page table for the data addresses. The shadow page table is linked to the standard page table by a pointer in page->lru.next of the struct page corresponding to the page that contains the standard page table (since page->private is not really private with the pte_lock and the page table pages are not in the LRU list). Depending on the software bits of a pte, it is either inserted into both page tables or just into the standard (data) page table. Pages of a vma that does not have the VM_EXEC bit set get mapped only in the data address space. Any try to execute code on such a page will cause a page translation exception. The standard reaction to this is a SIGSEGV with two exceptions: the two system call opcodes 0x0a77 (sys_sigreturn) and 0x0aad (sys_rt_sigreturn) are allowed. They are stored by the kernel to the signal stack frame. Unfortunately, the signal return mechanism cannot be modified to use an SA_RESTORER because the exception unwinding code depends on the system call opcode stored behind the signal stack frame. This feature requires that user space is executed in secondary-space mode and the kernel in home-space mode, which means that the addressing modes need to be switched and that the noexec protection only works for user space. After switching the addressing modes, we cannot use the mvcp/mvcs instructions anymore to copy between kernel and user space. A new mvcos instruction has been added to the z9 EC/BC hardware which allows to copy between arbitrary address spaces, but on older hardware the page tables need to be walked manually. Signed-off-by: Gerald Schaefer <geraldsc@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2007-02-05[S390] Get rid of a lot of sparse warnings.Heiko Carstens4-27/+47
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>