ARC700 doesn't natively support unaligned access, but can be emulated
-Unaligned Access Exception
-Disassembly at the Fault address to find the exact insn (long/short)
Also per Arnd's comment, we runtime control it using 2 sysctl knobs:
* SYSCTL_ARCH_UNALIGN_ALLOW: Runtime enable/disble
* SYSCTL_ARCH_UNALIGN_NO_WARN: Warn on each emulation attempt
Originally contributed by Tim Yao <tim.yao@amlogic.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Cc: Tim Yao <tim.yao@amlogic.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
PARISC defines /proc/sys/kernel/unaligned-trap to runtime toggle
unaligned access emulation.
The exact mechanics of enablig/disabling are still arch specific, we can
make the sysctl usable by other arches.
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Acked-by: Helge Deller <deller@gmx.de>
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Cc: Helge Deller <deller@gmx.de>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Serge Hallyn <serge.hallyn@canonical.com>
-Originally written by Rajeshwar Ranga
-Derived off of generic unwinder in 2.6.19 and adapted to ARC
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Cc: Rajeshwar Ranga <rajeshwar.ranga@gmail.com>
ARC common code to enable a SMP system + ISS provided SMP extensions.
ARC700 natively lacks SMP support, hence some of the core features are
are only enabled if SoCs have the necessary h/w pixie-dust. This
includes:
-Inter Processor Interrupts (IPI)
-Cache coherency
-load-locked/store-conditional
...
The low level exception handling would be completely broken in SMP
because we don't have hardware assisted stack switching. Thus a fair bit
of this code is repurposing the MMU_SCRATCH reg for event handler
prologues to keep them re-entrant.
Many thanks to Rajeshwar Ranga for his initial "major" contributions to
SMP Port (back in 2008), and to Noam Camus and Gilad Ben-Yossef for help
with resurrecting that in 3.2 kernel (2012).
Note that this platform code is again singleton design pattern - so
multiple SMP platforms won't build at the moment - this deficiency is
addressed in subsequent patches within this series.
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Rajeshwar Ranga <rajeshwar.ranga@gmail.com>
Cc: Noam Camus <noamc@ezchip.com>
Cc: Gilad Ben-Yossef <gilad@benyossef.com>
There is a bit of hack/kludge right now where we disable preemption if a
L2 (High prio) IRQ is taken while L1 (Low prio) is active.
Need to revisit this
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
This was part of port buildup strategy from Arnd to have a minimal kernel
at first and then add optional features (stacktracing, ptrace, smp,
kprobes, oprofile....)
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
* arc-uart platform device now populated dynamically, using
of_platform_populate() - applies to any other device whatsoever.
* uart in turn requires incore arc-intc to be also present in DT
* A irq-domain needs to be instantiated for IRQ requests by DT probed
device (e.g. arc-uart)
TODO: switch over to linear irq domain once all devs have been
transitioned to DT
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Cc: Grant Likely <grant.likely@secretlab.ca>
Cc: Arnd Bergmann <arnd@arndb.de>
This is minimal infrastructure needed for devicetree work.
It uses an a sample "skeleton" devicetree - embedded in kernel image -
to print the board, manufacturer by parsing the top-level "compatible"
string.
As of now we don't need any additional "board" specific "machine_desc".
TODO: support interpreting the command line as boot-loader passed dtb
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Grant Likely <grant.likely@secretlab.ca>
Cc: devicetree-discuss@lists.ozlabs.org
Cc: Rob Herring <rob.herring@calxeda.com>
Cc: James Hogan <james.hogan@imgtec.com>
Reviewed-by: Rob Herring <rob.herring@calxeda.com>
Reviewed-by: James Hogan <james.hogan@imgtec.com>
N.B. This is old style of hardcoding platform device specific info
in code and it's instantiation thererof using platform_add_devices().
Subsequent patches replace this with DeviceTree based runtime probe.
This patch has been retained just as an example of "don't-do-this" for
newer kernel ports.
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Cc: Arnd Bergmann <arnd@arndb.de>
This includes recent changes to make handler "retry" and/or "killable"
The killable (early exit) logic is loosely based on how SH implements it
return if SIGKILL + either of VM_FAULT_OOM or VM_FAULT_RETRY
which is different from Hexagon implementation which would NOT early
exit for
SIGKILL + VM_FAULT_OOM + !VM_FAULT_RETRY
credits: Non executable stack support from Simon Spooner
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
ARC700 MMU provides for tagging TLB entries with a 8-bit ASID to avoid
having to flush the TLB every task switch.
It also allows for a quick way to invalidate all the TLB entries for
task useful for:
* COW sementics during fork()
* task exit()ing
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
* ARC700 has VIPT L1 Caches
* Caches don't snoop and are not coherent
* Given the PAGE_SIZE and Cache associativity, we don't support aliasing
D$ configurations (yet), but do allow aliasing I$ configs
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Per Al Viro's "signals for dummies" https://lkml.org/lkml/2012/12/6/366
there are 3 golden rules for (not) restarting syscalls:
" What we need to guarantee is
* restarts do not happen on signals caught in interrupts or exceptions
* restarts do not happen on signals caught in sigreturn()
* restart should happen only once, even if we get through do_signal()
many times."
ARC Port already handled #1, this patch fixes#2 and #3.
We use the additional state in pt_regs->orig_r8 to ckh if restarting
has already been done once.
Thanks to Al Viro for spotting this.
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
To avoid multiple syscall restarts (multiple signals) or no restart at
all (sigreturn), we need just an extra bit of state "literally 1 bit" in
struct pt_regs. orig_r8 is the best place to do this, however given the
way it is encoded currently, we can't add anything simplistically.
Current orig_r8:
* syscalls -> 1 to NR_SYSCALLS
* Exceptions -> NR_SYSCALLS + 1
* Break-point-> NR_SYSCALLS + 2
In new scheme it is a bit-field
* lower short word contains the exact event type (and a new bit to represent
restart semantics : if syscall was already / can't be restarted)
* upper short word optionally containing the syscall num - needed by
likes of tracehooks etc
This patch only changes how orig_r8 is organised and nothing should
change behaviourily.
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
And fix a kzalloc argument inversion bug while converting to devres.
Signed-off-by: Aaron Sierra <asierra@xes-inc.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Includes following fixes courtesy review by Al-Viro
* Tracer poke to Callee-regs were lost
Before going off into do_signal( ) we save the user-mode callee regs
(as they are not saved by default as part of pt_regs). This is to make
sure that that a Tracer (if tracing related signal) is able to do likes
of PEEKUSR(callee-reg).
However in return path we were simply discarding the user-mode callee
regs, which would break a POKEUSR(callee-reg) from a tracer.
* Issue related to multiple syscall restarts are addressed in next patch
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Acked-by: Jonas Bonn <jonas@southpole.se>
schedule_delayed_work() is using msec instead of jiffies. On PLOGI
reject from target, remote port retry is scheduled @ 20 sec instead
of 2sec(FC_DEF_E_D_TOV).
XenServer dom0 kernel is configured with CONFIG_HZ=100Hz
Signed-off-by: Krishna Mohan <krmohan@cisco.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
x86/mm2 is testing out fine, but has developed conflicts with x86/mm
due to patches in adjacent code. Merge them so we can drop x86/mm2
and have a unified branch.
Resolved Conflicts:
arch/x86/kernel/setup.c
Even though nlmclnt_reclaim() is only one call into the stack frame,
928 bytes on the stack seems like a lot. Recode to dynamically
allocate the request structure once from within the reclaimer task,
then pass this pointer into nlmclnt_reclaim() for reuse on
subsequent calls.
smatch analysis:
fs/lockd/clntproc.c:620 nlmclnt_reclaim() warn: 'reqst' puts
928 bytes on stack
Also remove redundant assignment of 0 after memset.
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Tim Gardner <tim.gardner@canonical.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Currently, NFSd is ready to operate in network namespace based containers.
So let's drop check for "init_net" and make it able to fly.
Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
This tracker uses khelper kthread to execute binaries.
Execution itself is done from kthread context - i.e. global root is used.
This is not suitable for containers with own root.
So, disable this tracker for a while.
Note: one of possible solutions can be pass "init" callback to khelper, which
will swap root to desired one.
Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Functuon "exports_open" is used for both "/proc/fs/nfs/exports" and
"/proc/fs/nfsd/exports" files.
Now NFSd filesystem is containerised, so proper net can be taken from
superblock for "/proc/fs/nfsd/exports" reader.
But for "/proc/fs/nfsd/exports" only current->nsproxy->net_ns can be used.
Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
This patch makes NFSD file system superblock to be created per net.
This makes possible to get proper network namespace from superblock instead of
using hard-coded "init_net".
Note: NFSd fs super-block holds network namespace. This garantees, that
network namespace won't disappear from underneath of it.
This, obviously, means, that in case of kill of a container's "init" (which is not a mount
namespace, but network namespace creator) netowrk namespace won't be
destroyed.
Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Using wait_for_completion() for waiting for a IO request to be executed
results in wrong iowait time accounting. For example, a system having
the only task doing write() and fdatasync() on a block device can be
reported being idle instead of iowaiting as it should because
blkdev_issue_flush() calls wait_for_completion() which in turn calls
schedule() that does not increment the iowait proc counter and thus does
not turn on iowait time accounting.
The patch makes block layer use wait_for_completion_io() instead of
wait_for_completion() where appropriate to account iowait time
correctly.
Signed-off-by: Vladimir Davydov <vdavydov@parallels.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The only difference between wait_for_completion[_timeout]() and
wait_for_completion_io[_timeout]() is that the latter calls
io_schedule_timeout() instead of schedule_timeout() so that the caller
is accounted as waiting for IO, not just sleeping.
These functions can be used for correct iowait time accounting when the
completion struct is actually used for waiting for IO (e.g. completion
of a bio request in the block layer).
Signed-off-by: Vladimir Davydov <vdavydov@parallels.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Since mesh powersaving was added, pending bcast/mcast frames may go out the
CAB queue now. Unfortunately, the queue was only set up for AP mode, so we
would try to tx on the IEEE80211_INVAL_HW_QUEUE. Allow cab_queue for mesh
interfaces as well.
Fixes the following warning (or crash without MAC80211_VERBOSE_DEBUG):
WARNING: at net/mac80211/tx.c:1223 __ieee80211_tx+0x162/0x35f [mac80211]()
Modules linked in: mac80211_hwsim mac80211 cfg80211 [...]
Pid: 3085, comm: avahi-daemon Tainted: G W 3.8.0-rc1+ #377
Call Trace:
[<ffffffff81045c20>] warn_slowpath_common+0x83/0x9c
[<ffffffff81045c53>] warn_slowpath_null+0x1a/0x1c
[<ffffffffa083aef0>] __ieee80211_tx+0x162/0x35f [mac80211]
[<ffffffffa083cb1d>] ieee80211_tx+0xd3/0xf9 [mac80211]
[<ffffffffa083cc0f>] ieee80211_xmit+0xcc/0xd5 [mac80211]
[<ffffffffa083db59>] ieee80211_subif_start_xmit+0xc53/0xcd8 [mac80211]
[<ffffffff81319acd>] dev_hard_start_xmit+0x259/0x3ce
[<ffffffff81333d6b>] sch_direct_xmit+0x74/0x17d
[<ffffffff8131a0b1>] dev_queue_xmit+0x230/0x414
[<ffffffff8134877a>] ip_finish_output2+0x348/0x3aa
[<ffffffff81349029>] ip_finish_output+0x6c/0x71
[<ffffffff81349046>] NF_HOOK_COND.constprop.44+0x18/0x58
[<ffffffff8134a03a>] ip_mc_output+0x134/0x13c
[<ffffffff8134835a>] dst_output+0x18/0x1c
[<ffffffff81349a24>] ip_local_out+0x20/0x24
[<ffffffff8134a8cf>] ip_send_skb+0x16/0x3c
[<ffffffff8136bfba>] udp_send_skb+0x254/0x2b9
[<ffffffff8136c85e>] udp_sendmsg+0x5a8/0x7d4
Signed-off-by: Bob Copeland <bob@cozybit.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
The reason to move cache_request() callback call from
sunrpc_cache_pipe_upcall() to cache_read() is that this garantees, that cache
access will be done userspace process context (only userspace process have
proper root context).
This is required for NFSd support in container: svc_export_request() (which is
cache_request callback) calls d_path(), which, in turn, traverse dentry up to
current->fs->root. Kernel threads always have global root, while container
have be in "root jail" - i.e. have it's own nested root.
Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Passing this pointer is redundant since it's stored on cache_detail structure,
which is also passed to sunrpc_cache_pipe_upcall () function.
Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
For most of SUNRPC caches (except NFS DNS cache) cache_detail->cache_upcall is
redundant since all that it's implementations are doing is calling
sunrpc_cache_pipe_upcall() with proper function address argument.
Cache request function address is now stored on cache_detail structure and
thus all the code can be simplified.
Now, for those cache details, which doesn't have cache_upcall callback (the
only one, which still has is nfs_dns_resolve_template)
sunrpc_cache_pipe_upcall will be called instead.
Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
This callback will allow to simplify upcalls in further patches in this
series.
Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
This is a cleanup patch.
Such helpers like nfs_cache_init() and nfs_cache_destroy() are redundant,
because they are just a wrappers around sunrpc_init_cache_detail() and
sunrpc_destroy_cache_detail() respectively.
So let's remove them completely and move corresponding logic to
nfs_cache_register_net() and nfs_cache_unregister_net() respectively (since
they are called together anyway).
Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
This cache was the first containerized and doesn't use net-aware cache
creation and destruction helpers.
This is a cleanup patch which just makes code looks clearer and reduce amount
of lines of code.
Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
