Tejun Heo [Thu, 24 Jan 2013 19:01:33 +0000 (11:01 -0800)]
workqueue: move busy_hash from global_cwq to worker_pool
There's no functional necessity for the two pools on the same CPU to
share the busy hash table. It's also likely to be a bottleneck when
implementing pools with user-specified attributes.
This patch makes busy_hash per-pool. The conversion is mostly
straight-forward. Changes worth noting are,
* Large block of changes in rebind_workers() is moving the block
inside for_each_worker_pool() as now there are separate hash tables
for each pool. This changes the order of operations but doesn't
break anything.
* Thre for_each_worker_pool() loops in gcwq_unbind_fn() are combined
into one. This again changes the order of operaitons but doesn't
break anything.
This is part of an effort to remove global_cwq and make worker_pool
the top level abstraction, which in turn will help implementing worker
pools with user-specified attributes.
Signed-off-by: Tejun Heo <tj@kernel.org> Reviewed-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Tejun Heo [Thu, 24 Jan 2013 19:01:33 +0000 (11:01 -0800)]
workqueue: record pool ID instead of CPU in work->data when off-queue
Currently, when a work item is off-queue, work->data records the CPU
it was last on, which is used to locate the last executing instance
for non-reentrance, flushing, etc.
We're in the process of removing global_cwq and making worker_pool the
top level abstraction. This patch makes work->data point to the pool
it was last associated with instead of CPU.
After the previous WORK_OFFQ_POOL_CPU and worker_poo->id additions,
the conversion is fairly straight-forward. WORK_OFFQ constants and
functions are modified to record and read back pool ID instead.
worker_pool_by_id() is added to allow looking up pool from ID.
get_work_pool() replaces get_work_gcwq(), which is reimplemented using
get_work_pool(). get_work_pool_id() replaces work_cpu().
This patch shouldn't introduce any observable behavior changes.
Signed-off-by: Tejun Heo <tj@kernel.org> Reviewed-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Tejun Heo [Thu, 24 Jan 2013 19:01:33 +0000 (11:01 -0800)]
workqueue: introduce WORK_OFFQ_CPU_NONE
Currently, when a work item is off queue, high bits of its data
encodes the last CPU it was on. This is scheduled to be changed to
pool ID, which will make it impossible to use WORK_CPU_NONE to
indicate no association.
This patch limits the number of bits which are used for off-queue cpu
number to 31 (so that the max fits in an int) and uses the highest
possible value - WORK_OFFQ_CPU_NONE - to indicate no association.
Signed-off-by: Tejun Heo <tj@kernel.org> Reviewed-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Tejun Heo [Thu, 24 Jan 2013 19:01:33 +0000 (11:01 -0800)]
workqueue: make GCWQ_FREEZING a pool flag
Make GCWQ_FREEZING a pool flag POOL_FREEZING. This patch doesn't
change locking - FREEZING on both pools of a CPU are set or clear
together while holding gcwq->lock. It shouldn't cause any functional
difference.
This leaves gcwq->flags w/o any flags. Removed.
While at it, convert BUG_ON()s in freeze_workqueue_begin() and
thaw_workqueues() to WARN_ON_ONCE().
This is part of an effort to remove global_cwq and make worker_pool
the top level abstraction, which in turn will help implementing worker
pools with user-specified attributes.
Signed-off-by: Tejun Heo <tj@kernel.org> Reviewed-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Tejun Heo [Thu, 24 Jan 2013 19:01:33 +0000 (11:01 -0800)]
workqueue: make GCWQ_DISASSOCIATED a pool flag
Make GCWQ_DISASSOCIATED a pool flag POOL_DISASSOCIATED. This patch
doesn't change locking - DISASSOCIATED on both pools of a CPU are set
or clear together while holding gcwq->lock. It shouldn't cause any
functional difference.
This is part of an effort to remove global_cwq and make worker_pool
the top level abstraction, which in turn will help implementing worker
pools with user-specified attributes.
Signed-off-by: Tejun Heo <tj@kernel.org> Reviewed-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Tejun Heo [Thu, 24 Jan 2013 19:01:33 +0000 (11:01 -0800)]
workqueue: use std_ prefix for the standard per-cpu pools
There are currently two worker pools per cpu (including the unbound
cpu) and they are the only pools in use. New class of pools are
scheduled to be added and some pool related APIs will be added
inbetween. Call the existing pools the standard pools and prefix them
with std_. Do this early so that new APIs can use std_ prefix from
the beginning.
This patch doesn't introduce any functional difference.
Signed-off-by: Tejun Heo <tj@kernel.org> Reviewed-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Tejun Heo [Fri, 18 Jan 2013 22:05:56 +0000 (14:05 -0800)]
workqueue: implement current_is_async()
This function queries whether %current is an async worker executing an
async item. This will be used to implement warning on synchronous
request_module() from async workers.
Tejun Heo [Fri, 18 Jan 2013 22:05:55 +0000 (14:05 -0800)]
workqueue: move struct worker definition to workqueue_internal.h
This will be used to implement an inline function to query whether
%current is a workqueue worker and, if so, allow determining which
work item it's executing.
Tejun Heo [Fri, 18 Jan 2013 22:05:55 +0000 (14:05 -0800)]
workqueue: rename kernel/workqueue_sched.h to kernel/workqueue_internal.h
Workqueue wants to expose more interface internal to kernel/. Instead
of adding a new header file, repurpose kernel/workqueue_sched.h.
Rename it to workqueue_internal.h and add include protector.
This patch doesn't introduce any functional changes.
Tejun Heo [Fri, 18 Jan 2013 01:16:24 +0000 (17:16 -0800)]
workqueue: set PF_WQ_WORKER on rescuers
PF_WQ_WORKER is used to tell scheduler that the task is a workqueue
worker and needs wq_worker_sleeping/waking_up() invoked on it for
concurrency management. As rescuers never participate in concurrency
management, PF_WQ_WORKER wasn't set on them.
There's a need for an interface which can query whether %current is
executing a work item and if so which. Such interface requires a way
to identify all tasks which may execute work items and PF_WQ_WORKER
will be used for that. As all normal workers always have PF_WQ_WORKER
set, we only need to add it to rescuers.
As rescuers start with WORKER_PREP but never clear it, it's always
NOT_RUNNING and there's no need to worry about it interfering with
concurrency management even if PF_WQ_WORKER is set; however, unlike
normal workers, rescuers currently don't have its worker struct as
kthread_data(). It uses the associated workqueue_struct instead.
This is problematic as wq_worker_sleeping/waking_up() expect struct
worker at kthread_data().
This patch adds worker->rescue_wq and start rescuer kthreads with
worker struct as kthread_data and sets PF_WQ_WORKER on rescuers.
Tejun Heo [Wed, 19 Dec 2012 19:24:06 +0000 (11:24 -0800)]
workqueue: fix find_worker_executing_work() brekage from hashtable conversion
42f8570f43 ("workqueue: use new hashtable implementation") incorrectly
made busy workers hashed by the pointer value of worker instead of
work. This broke find_worker_executing_work() which in turn broke a
lot of fundamental operations of workqueue - non-reentrancy and
flushing among others. The flush malfunction triggered warning in
disk event code in Fengguang's automated test.
Tejun Heo [Tue, 18 Dec 2012 18:35:02 +0000 (10:35 -0800)]
workqueue: consider work function when searching for busy work items
To avoid executing the same work item concurrenlty, workqueue hashes
currently busy workers according to their current work items and looks
up the the table when it wants to execute a new work item. If there
already is a worker which is executing the new work item, the new item
is queued to the found worker so that it gets executed only after the
current execution finishes.
Unfortunately, a work item may be freed while being executed and thus
recycled for different purposes. If it gets recycled for a different
work item and queued while the previous execution is still in
progress, workqueue may make the new work item wait for the old one
although the two aren't really related in any way.
In extreme cases, this false dependency may lead to deadlock although
it's extremely unlikely given that there aren't too many self-freeing
work item users and they usually don't wait for other work items.
To alleviate the problem, record the current work function in each
busy worker and match it together with the work item address in
find_worker_executing_work(). While this isn't complete, it ensures
that unrelated work items don't interact with each other and in the
very unlikely case where a twisted wq user triggers it, it's always
onto itself making the culprit easy to spot.
Linus Torvalds [Tue, 18 Dec 2012 04:58:12 +0000 (20:58 -0800)]
Merge branch 'akpm' (Andrew's patch-bomb)
Merge misc patches from Andrew Morton:
"Incoming:
- lots of misc stuff
- backlight tree updates
- lib/ updates
- Oleg's percpu-rwsem changes
- checkpatch
- rtc
- aoe
- more checkpoint/restart support
I still have a pile of MM stuff pending - Pekka should be merging
later today after which that is good to go. A number of other things
are twiddling thumbs awaiting maintainer merges."
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (180 commits)
scatterlist: don't BUG when we can trivially return a proper error.
docs: update documentation about /proc/<pid>/fdinfo/<fd> fanotify output
fs, fanotify: add @mflags field to fanotify output
docs: add documentation about /proc/<pid>/fdinfo/<fd> output
fs, notify: add procfs fdinfo helper
fs, exportfs: add exportfs_encode_inode_fh() helper
fs, exportfs: escape nil dereference if no s_export_op present
fs, epoll: add procfs fdinfo helper
fs, eventfd: add procfs fdinfo helper
procfs: add ability to plug in auxiliary fdinfo providers
tools/testing/selftests/kcmp/kcmp_test.c: print reason for failure in kcmp_test
breakpoint selftests: print failure status instead of cause make error
kcmp selftests: print fail status instead of cause make error
kcmp selftests: make run_tests fix
mem-hotplug selftests: print failure status instead of cause make error
cpu-hotplug selftests: print failure status instead of cause make error
mqueue selftests: print failure status instead of cause make error
vm selftests: print failure status instead of cause make error
ubifs: use prandom_bytes
mtd: nandsim: use prandom_bytes
...
CC drivers/firmware/efivars.o
drivers/firmware/efivars.c: In function ‘efivarfs_get_inode’:
drivers/firmware/efivars.c:886:31: error: incompatible types when assigning to type ‘kgid_t’ from type ‘int’
make[2]: *** [drivers/firmware/efivars.o] Error 1
make[1]: *** [drivers/firmware/efivars.o] Error 2
Fix the build error by removing the duplicate initialization of i_uid and
i_gid inode_init_always has already initialized them to 0.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Stephen Rothwell [Mon, 10 Dec 2012 08:50:57 +0000 (19:50 +1100)]
mm,numa: fix update_mmu_cache_pmd call
This build error is currently hidden by the fact that the x86
implementation of 'update_mmu_cache_pmd()' is a macro that doesn't use
its last argument, but commit b32967ff101a ("mm: numa: Add THP migration
for the NUMA working set scanning fault case") introduced a call with
the wrong third argument.
In the akpm tree, it causes this build error:
mm/migrate.c: In function 'migrate_misplaced_transhuge_page_put':
mm/migrate.c:1666:2: error: incompatible type for argument 3 of 'update_mmu_cache_pmd'
arch/x86/include/asm/pgtable.h:792:20: note: expected 'struct pmd_t *' but argument is of type 'pmd_t'
Fix it.
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Cyrill Gorcunov [Tue, 18 Dec 2012 00:05:16 +0000 (16:05 -0800)]
fs, fanotify: add @mflags field to fanotify output
The kernel keeps FAN_MARK_IGNORED_SURV_MODIFY bit separately from
fsnotify_mark::mask|ignored_mask thus put it in @mflags (mark flags)
field so the user-space reader will be able to detect if such bit were
used on mark creation procedure.
Cyrill Gorcunov [Tue, 18 Dec 2012 00:05:06 +0000 (16:05 -0800)]
fs, exportfs: escape nil dereference if no s_export_op present
This routine will be used to generate a file handle in fdinfo output for
inotify subsystem, where if no s_export_op present the general
export_encode_fh should be used. Thus add a test if s_export_op present
inside exportfs_encode_fh itself.
Cyrill Gorcunov [Tue, 18 Dec 2012 00:04:55 +0000 (16:04 -0800)]
procfs: add ability to plug in auxiliary fdinfo providers
This patch brings ability to print out auxiliary data associated with
file in procfs interface /proc/pid/fdinfo/fd.
In particular further patches make eventfd, evenpoll, signalfd and
fsnotify to print additional information complete enough to restore
these objects after checkpoint.
To simplify the code we add show_fdinfo callback inside struct
file_operations (as Al and Pavel are proposing).
Dave Jones [Tue, 18 Dec 2012 00:04:52 +0000 (16:04 -0800)]
tools/testing/selftests/kcmp/kcmp_test.c: print reason for failure in kcmp_test
I was curious why sys_kcmp wasn't working, which led me to the testcase.
It turned out I hadn't enabled CHECKPOINT_RESTORE in the kernel I was
testing. Add a decoding of errno to the testcase to make that obvious.
Signed-off-by: Dave Jones <davej@redhat.com> Acked-by: Cyrill Gorcunov <gorcunov@openvz.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Dave Young [Tue, 18 Dec 2012 00:04:50 +0000 (16:04 -0800)]
breakpoint selftests: print failure status instead of cause make error
In case breakpoint test exit non zero value it will cause make error.
Better way is just print the test failure status.
Signed-off-by: Dave Young <dyoung@redhat.com> Reviewed-by: Pekka Enberg <penberg@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Dave Young [Tue, 18 Dec 2012 00:04:49 +0000 (16:04 -0800)]
kcmp selftests: print fail status instead of cause make error
In case kcmp_test exit non zero value it will cause make error.
Better way is just print the test failure status.
Signed-off-by: Dave Young <dyoung@redhat.com> Reviewed-by: Pekka Enberg <penberg@kernel.org> Cc: Cyrill Gorcunov <gorcunov@openvz.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Dave Young [Tue, 18 Dec 2012 00:04:47 +0000 (16:04 -0800)]
kcmp selftests: make run_tests fix
make run_tests need the target is run_tests instead of run-tests
Also gcc output should be kcmp_test. Fix these two issues.
Signed-off-by: Dave Young <dyoung@redhat.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: Cyrill Gorcunov <gorcunov@openvz.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
After applying the patch:
bash-4.1$ make -C memory-hotplug run_tests
make: Entering directory `/home/dave/git/linux-2.6/tools/testing/selftests/memory-hotplug'
/bin/sh: ./on-off-test.sh: Permission denied
memory-hotplug selftests: [FAIL]
make: Leaving directory `/home/dave/git/linux-2.6/tools/testing/selftests/memory-hotplug'
Signed-off-by: Dave Young <dyoung@redhat.com> Reviewed-by: Pekka Enberg <penberg@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
After applying the patch:
bash-4.1$ make -C cpu-hotplug run_tests
make: Entering directory `/home/dave/git/linux-2.6/tools/testing/selftests/cpu-hotplug'
/bin/sh: ./on-off-test.sh: Permission denied
cpu-hotplug selftests: [FAIL]
make: Leaving directory `/home/dave/git/linux-2.6/tools/testing/selftests/cpu-hotplug'
Signed-off-by: Dave Young <dyoung@redhat.com> Reviewed-by: Pekka Enberg <penberg@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Dave Young [Tue, 18 Dec 2012 00:04:39 +0000 (16:04 -0800)]
mqueue selftests: print failure status instead of cause make error
Original behavior:
bash-4.1$ make -C mqueue run_tests
make: Entering directory `/home/dave/git/linux-2.6/tools/testing/selftests/mqueue'
./mq_open_tests /test1
Not running as root, but almost all tests require root in order to modify
system settings. Exiting.
make: *** [run_tests] Error 1
make: Leaving directory `/home/dave/git/linux-2.6/tools/testing/selftests/mqueue'
After applying the patch:
bash-4.1$ make -C mqueue run_tests
make: Entering directory `/home/dave/git/linux-2.6/tools/testing/selftests/mqueue'
Not running as root, but almost all tests require root in order to modify
system settings. Exiting.
mq_open_tests: [FAIL]
Not running as root, but almost all tests require root in order to modify
system settings. Exiting.
mq_perf_tests: [FAIL]
make: Leaving directory `/home/dave/git/linux-2.6/tools/testing/selftests/mqueue'
Signed-off-by: Dave Young <dyoung@redhat.com> Reviewed-by: Pekka Enberg <penberg@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Dave Young [Tue, 18 Dec 2012 00:04:38 +0000 (16:04 -0800)]
vm selftests: print failure status instead of cause make error
Original behavior:
bash-4.1$ make -C vm run_tests
make: Entering directory `/home/dave/git/linux-2.6/tools/testing/selftests/vm'
/bin/sh ./run_vmtests
./run_vmtests: line 24: /proc/sys/vm/nr_hugepages: Permission denied
Please run this test as root
make: *** [run_tests] Error 1
make: Leaving directory `/home/dave/git/linux-2.6/tools/testing/selftests/vm'
After applying the patch:
bash-4.1$ make -C vm run_tests
make: Entering directory `/home/dave/git/linux-2.6/tools/testing/selftests/vm'
./run_vmtests: line 24: /proc/sys/vm/nr_hugepages: Permission denied
Please run this test as root
vmtests: [FAIL]
make: Leaving directory `/home/dave/git/linux-2.6/tools/testing/selftests/vm'
Signed-off-by: Dave Young <dyoung@redhat.com> Cc: Pekka Enberg <penberg@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Akinobu Mita [Tue, 18 Dec 2012 00:04:25 +0000 (16:04 -0800)]
prandom: introduce prandom_bytes() and prandom_bytes_state()
Add functions to get the requested number of pseudo-random bytes.
The difference from get_random_bytes() is that it generates pseudo-random
numbers by prandom_u32(). It doesn't consume the entropy pool, and the
sequence is reproducible if the same rnd_state is used. So it is suitable
for generating random bytes for testing.
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Cc: "Theodore Ts'o" <tytso@mit.edu> Cc: Artem Bityutskiy <dedekind1@gmail.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Eilon Greenstein <eilong@broadcom.com> Cc: David Laight <david.laight@aculab.com> Cc: Michel Lespinasse <walken@google.com> Cc: Robert Love <robert.w.love@intel.com> Cc: Valdis Kletnieks <valdis.kletnieks@vt.edu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Akinobu Mita [Tue, 18 Dec 2012 00:04:23 +0000 (16:04 -0800)]
random32: rename random32 to prandom
This renames all random32 functions to have 'prandom_' prefix as follows:
void prandom_seed(u32 seed); /* rename from srandom32() */
u32 prandom_u32(void); /* rename from random32() */
void prandom_seed_state(struct rnd_state *state, u64 seed);
/* rename from prandom32_seed() */
u32 prandom_u32_state(struct rnd_state *state);
/* rename from prandom32() */
The purpose of this renaming is to prevent some kernel developers from
assuming that prandom32() and random32() might imply that only
prandom32() was the one using a pseudo-random number generator by
prandom32's "p", and the result may be a very embarassing security
exposure. This concern was expressed by Theodore Ts'o.
And furthermore, I'm going to introduce new functions for getting the
requested number of pseudo-random bytes. If I continue to use both
prandom32 and random32 prefixes for these functions, the confusion
is getting worse.
As a result of this renaming, "prandom_" is the common prefix for
pseudo-random number library.
Currently, srandom32() and random32() are preserved because it is
difficult to rename too many users at once.
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Cc: "Theodore Ts'o" <tytso@mit.edu> Cc: Robert Love <robert.w.love@intel.com> Cc: Michel Lespinasse <walken@google.com> Cc: Valdis Kletnieks <valdis.kletnieks@vt.edu> Cc: David Laight <david.laight@aculab.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Artem Bityutskiy <dedekind1@gmail.com> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Eilon Greenstein <eilong@broadcom.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Ed Cashin [Tue, 18 Dec 2012 00:04:19 +0000 (16:04 -0800)]
aoe: update internal version number to 81
This version number is printed to the console on module initialization
and is available in sysfs, which is where the userland aoe-version tool
looks for it.
Signed-off-by: Ed Cashin <ecashin@coraid.com> Cc: Jens Axboe <axboe@kernel.dk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Ed Cashin [Tue, 18 Dec 2012 00:04:17 +0000 (16:04 -0800)]
aoe: identify source of runt AoE packets
This change only affects experimental AoE storage networks.
It modifies the console message about runt packets detected so that the
AoE major and minor addresses of the AoE target that generated the runt
are mentioned.
Signed-off-by: Ed Cashin <ecashin@coraid.com> Cc: Jens Axboe <axboe@kernel.dk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Ed Cashin [Tue, 18 Dec 2012 00:04:15 +0000 (16:04 -0800)]
aoe: allow comma separator in aoe_iflist value
By default, the aoe driver uses any ethernet interface for AoE, but the
aoe_iflist module parameter provides a convenient way to limit AoE
traffic to a specific list of local network interfaces.
This change allows a list to be specified using the comma character as a
separator. For example,
modprobe aoe aoe_iflist=eth2,eth3
Before, it was inconvenient to get the quoting right in shell scripts
when setting aoe_iflist to have more than one network interface.
Signed-off-by: Ed Cashin <ecashin@coraid.com> Cc: Jens Axboe <axboe@kernel.dk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Ed Cashin [Tue, 18 Dec 2012 00:04:14 +0000 (16:04 -0800)]
aoe: allow user to disable target failure timeout
With this change, the aoe driver treats the value zero as special for
the aoe_deadsecs module parameter. Normally, this value specifies the
number of seconds during which the driver will continue to attempt
retransmits to an unresponsive AoE target. After aoe_deadsecs has
elapsed, the aoe driver marks the aoe device as "down" and fails all
I/O.
The new meaning of an aoe_deadsecs of zero is for the driver to
retransmit commands indefinitely.
Signed-off-by: Ed Cashin <ecashin@coraid.com> Cc: Jens Axboe <axboe@kernel.dk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Ed Cashin [Tue, 18 Dec 2012 00:04:11 +0000 (16:04 -0800)]
aoe: use dynamic number of remote ports for AoE storage target
Many AoE targets have four or fewer network ports, but some existing
storage devices have many, and the AoE protocol sets no limit.
This patch allows the use of more than eight remote MAC addresses per AoE
target, while reducing the amount of memory used by the aoe driver in
cases where there are many AoE targets with fewer than eight MAC addresses
each.
Signed-off-by: Ed Cashin <ecashin@coraid.com> Cc: Jens Axboe <axboe@kernel.dk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Ed Cashin [Tue, 18 Dec 2012 00:04:09 +0000 (16:04 -0800)]
aoe: avoid races between device destruction and discovery
This change avoids a race that could result in a NULL pointer derference
following a WARNing from kobject_add_internal, "don't try to register
things with the same name in the same directory."
The problem was found with a test that forgets and discovers an
aoe device in a loop:
while test ! -r /tmp/stop; do
aoe-flush -a
aoe-discover
done
The race was between aoedev_flush taking aoedevs out of the devlist,
allowing a new discovery of the same AoE target to take place before the
driver gets around to calling sysfs_remove_group. Fixing that one
revealed another race between do_open and add_disk, and this patch avoids
that, too.
The fix required some care, because for flushing (forgetting) an aoedev,
some of the steps must be performed under lock and some must be able to
sleep. Also, for discovering a new aoedev, some steps might sleep.
The check for a bad aoedev pointer remains from a time when about half of
this patch was done, and it was possible for the
bdev->bd_disk->private_data to become corrupted. The check should be
removed eventually, but it is not expected to add significant overhead,
occurring in the aoeblk_open routine.
Signed-off-by: Ed Cashin <ecashin@coraid.com> Cc: Jens Axboe <axboe@kernel.dk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Ed Cashin [Tue, 18 Dec 2012 00:04:08 +0000 (16:04 -0800)]
aoe: improve handling of misbehaving network paths
An AoE target can have multiple network ports used for AoE, and in the
aoe driver, those are tracked by the aoetgt struct. These changes allow
the aoe driver to handle network paths, or aoetgts, that are not working
well, compared to the others.
Paths that do not get responses despite the retransmission of AoE
commands are marked as "tainted", and non-tainted paths are preferred.
Meanwhile, the aoe driver attempts to "probe" the tainted path in the
background by issuing reads of LBA 0 that are padded out to full
(possibly jumbo-frame) size. If the probes get responses, then the path
is "redeemed", and its taint is removed.
This mechanism has been shown to be helpful in transparently handling
and recovering from real-world network "brown outs" in ways that the
earlier "shoot the help-needing target in the head" mechanism could not.
Signed-off-by: Ed Cashin <ecashin@coraid.com> Cc: Jens Axboe <axboe@kernel.dk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Ed Cashin [Tue, 18 Dec 2012 00:04:06 +0000 (16:04 -0800)]
aoe: return real minor number for static minors
The value returned by the static minor device number number allocator is
the real minor number, so it must be multiplied by the supported number
of partitions per aoedev.
Without this fix the support for systems without udev is incomplete, and
the few users of aoe on such systems will have surprising results when
device nodes names do not match the AoE target.
Signed-off-by: Ed Cashin <ecashin@coraid.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Ed Cashin [Tue, 18 Dec 2012 00:04:04 +0000 (16:04 -0800)]
aoe: initialize sysminor to avoid compiler warning
Because the minor_get and related functions use the return values for
errors, the compiler doesn't know that sysminor will always either 1) be
initialized in aoedev_by_aoeaddr by the call to minor_get, or 2) be
unused as the "goto out" is executed.
This patch avoids the compiler warning.
Signed-off-by: Ed Cashin <ecashin@coraid.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Ed Cashin [Tue, 18 Dec 2012 00:04:03 +0000 (16:04 -0800)]
aoe: make error messages more specific in static minor allocation
For some special-purpose systems where udev isn't present, static
allocation of minor numbers is desirable. This update distinguishes
different failure scenarios, to help the user understand what went
wrong.
Signed-off-by: Ed Cashin <ecashin@coraid.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Ed Cashin [Tue, 18 Dec 2012 00:04:02 +0000 (16:04 -0800)]
aoe: remove call to request handler from I/O completion
There is no need to call the request handler function in the I/O
completion routine. The user impact of not doing it is a more "nice" aoe
driver that is less susceptible to causing soft lockups.
Signed-off-by: Ed Cashin <ecashin@coraid.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Ed Cashin [Tue, 18 Dec 2012 00:04:00 +0000 (16:04 -0800)]
aoe: increase default cap on outstanding AoE commands in the network
The aoe driver will never be waiting for more than aoe_maxout AoE
commands from a given remote network port on an AoE target. Increasing
the cap increases performance. Users can tighten the setting to reduce
the amount of memory used for handling AoE traffic or the network
bandwidth used for AoE.
Signed-off-by: Ed Cashin <ecashin@coraid.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Ed Cashin [Tue, 18 Dec 2012 00:03:58 +0000 (16:03 -0800)]
aoe: remove vestigial request queue allocation
Before the aoe driver was an I/O request handler, it was a
make_request-style block driver. Even so, there was a problem where
sysfs expected a request queue to exist, so one was provided in commit 7135a71b19be ("aoe: allocate unused request_queue for sysfs").
During the transition to the request-handler style, a patch was merged
that was based on a driver without the noop queue, and the noop queue
remained in place after the patch was merged, even though a new
functional queue was introduced by the patch, allocated through
blk_init_queue.
The user impact is a memory leak proportional to the number of AoE
targets discovered. This patch removes the memory leak and cleans up
vestiges of the old do-nothing queue from the aoeblk_gdalloc function.
Signed-off-by: Ed Cashin <ecashin@coraid.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Ed Cashin [Tue, 18 Dec 2012 00:03:55 +0000 (16:03 -0800)]
aoe: copy fallback timing information on destination failover
Commit f3b8e07af774 ("aoe: commands in retransmit queue use new
destination on failure") omits the copying of the coarse-grained time
when an AoE command was sent during the failover from one destination
MAC address on the AoE target to another.
The coarse-grained timing is only used when the system time changes or
an unlikely length of time has passed since the sending of the AoE
command. Users will not be impacted unless their system clock is very
inaccurate or something unusual (e.g., 10 GbE link reset) happens during
the period when the aoe driver is handling the failure of a port on the
AoE target. Being effected will mean that an AoE target could be
considered "down" too eagerly.
Signed-off-by: Ed Cashin <ecashin@coraid.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Ed Cashin [Tue, 18 Dec 2012 00:03:51 +0000 (16:03 -0800)]
aoe: commands in retransmit queue use new destination on failure
When one remote MAC address isn't working as a destination for AoE
commands, the frames used to track information associated with the AoE
commands are moved to a new aoetgt (defined by the tuple of {AoE major,
AoE minor, target MAC address}).
This patch makes sure that the frames on the queue for retransmits that
need to be done are updated to use the new destination, so that
retransmits will be sent through a working network path.
Without this change, packets on the retransmit queue will be needlessly
retransmitted to the unresponsive destination MAC, possibly causing
premature target failure before there's time for the retransmit timer to
run again, decide to retransmit again, and finally update the destination
to a working MAC address on the AoE target.
Signed-off-by: Ed Cashin <ecashin@coraid.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Ed Cashin [Tue, 18 Dec 2012 00:03:49 +0000 (16:03 -0800)]
aoe: use high-resolution RTTs with fallback to low-res
These changes improve the accuracy of the decision about whether it's time
to retransmit an AoE command by using the microsecond-resolution
gettimeofday instead of jiffies.
Because the system time can jump suddenly, the decision reverts to using
jiffies if the high-resolution time difference is relatively large.
Otherwise the AoE targets could be considered failed inappropriately.
Signed-off-by: Ed Cashin <ecashin@coraid.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Ed Cashin [Tue, 18 Dec 2012 00:03:47 +0000 (16:03 -0800)]
aoe: manipulate aoedev network stats under lock
With this bugfix in place the calculation of the criterion for "lateness"
is performed under lock. Without the lock, there is a chance that one of
the non-atomic operations performed on the round trip time statistics
could be incomplete, such that an incorrect lateness criterion would be
calculated.
Without this change, the effect of the bug would be rare unecessary but
benign retransmissions.
Signed-off-by: Ed Cashin <ecashin@coraid.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Ed Cashin [Tue, 18 Dec 2012 00:03:45 +0000 (16:03 -0800)]
aoe: err device: include MAC addresses for unexpected responses
The /dev/etherd/err character device provides low-level information about
normal but sometimes interesting AoE command retransmits and "unexpected
responses", i.e., responses for packets that have already been
retransmitted.
This change adds MAC addresses to the messages about unexpected responses,
so that when they occur, it's more easy to determine the network paths to
which they belong.
Signed-off-by: Ed Cashin <ecashin@coraid.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Ed Cashin [Tue, 18 Dec 2012 00:03:43 +0000 (16:03 -0800)]
aoe: improve network congestion handling
The aoe driver already had some congestion handling, but it was limited in
its ability to cope with the kind of congestion that can arise on more
complex networks such as those involving paths through multiple ethernet
switches.
Some of the lessons from TCP's history of development can be applied to
improving the congestion control and avoidance on AoE storage networks.
These changes use familar concepts from Van Jacobson's "Congestion
Avoidance and Control" paper from '88, without adding significant
overhead.
This patch depends on an upcoming patch that covers the failover case when
AoE commands being retransmitted are transferred from one retransmit queue
to another. Another upcoming patch increases the timing accuracy.
Signed-off-by: Ed Cashin <ecashin@coraid.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Ed Cashin [Tue, 18 Dec 2012 00:03:42 +0000 (16:03 -0800)]
aoe: provide ATA identify device content to user on request
Make the aoe driver follow expected behavior when the user uses ioctl to
get the ATA device identify information, allowing access to model, serial
number, etc.
Signed-off-by: Ed Cashin <ecashin@coraid.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Ed Cashin [Tue, 18 Dec 2012 00:03:34 +0000 (16:03 -0800)]
aoe: "payload" sysfs file exports per-AoE-command data transfer size
The userland aoetools package includes an "aoe-stat" command that can
display a "payload size" column when the aoe driver exports this
information. Users can quickly see what amount of user data is
transferred inside each AoE command on the network, network headers
excluded.
Signed-off-by: Ed Cashin <ecashin@coraid.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Ed Cashin [Tue, 18 Dec 2012 00:03:32 +0000 (16:03 -0800)]
aoe: support larger I/O requests via aoe_maxsectors module param
The GPFS filesystem is an example of an aoe user that requires the aoe
driver to support I/O request sizes larger than the default. Most users
will not need large I/O request sizes, because they would need to be split
up into multiple AoE commands anyway.
Signed-off-by: Ed Cashin <ecashin@coraid.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Ed Cashin [Tue, 18 Dec 2012 00:03:30 +0000 (16:03 -0800)]
aoe: support the forgetting (flushing) of a user-specified AoE target
Users sometimes want to cause the aoe driver to forget a particular
previously discovered device when it is no longer online. The aoetools
provide an "aoe-flush" command that users run to perform this
administrative task. The changes below provide the support needed in the
driver.
Signed-off-by: Ed Cashin <ecashin@coraid.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Ed Cashin [Tue, 18 Dec 2012 00:03:29 +0000 (16:03 -0800)]
aoe: update cap on outstanding commands based on config query response
The ATA over Ethernet config query response contains a "buffer count"
field reflecting the AoE target's capacity to buffer incoming AoE
commands.
By taking the current value of this field into accound, we increase
performance throughput or avoid network congestion, when the value
has increased or decreased, respectively.
Signed-off-by: Ed Cashin <ecashin@coraid.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Ed Cashin [Tue, 18 Dec 2012 00:03:25 +0000 (16:03 -0800)]
Documentation/sparse.txt: document context annotations for lock checking
The context feature of sparse is used with the Linux kernel sources to
check for imbalanced uses of locks. Document the annotations defined in
include/linux/compiler.h that tell sparse what to expect when a lock is
held on function entry, exit, or both.
Signed-off-by: Ed Cashin <ecashin@coraid.com> Reviewed-by: Josh Triplett <josh@joshtriplett.org> Acked-by: Christopher Li <sparse@chrisli.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Josh Triplett [Tue, 18 Dec 2012 00:03:24 +0000 (16:03 -0800)]
linux/compiler.h: add __must_hold macro for functions called with a lock held
linux/compiler.h has macros to denote functions that acquire or release
locks, but not to denote functions called with a lock held that return
with the lock still held. Add a __must_hold macro to cover that case.
Signed-off-by: Josh Triplett <josh@joshtriplett.org> Reported-by: Ed Cashin <ecashin@coraid.com> Tested-by: Ed Cashin <ecashin@coraid.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Kees Cook [Tue, 18 Dec 2012 00:03:20 +0000 (16:03 -0800)]
exec: use -ELOOP for max recursion depth
To avoid an explosion of request_module calls on a chain of abusive
scripts, fail maximum recursion with -ELOOP instead of -ENOEXEC. As soon
as maximum recursion depth is hit, the error will fail all the way back
up the chain, aborting immediately.
This also has the side-effect of stopping the user's shell from attempting
to reexecute the top-level file as a shell script. As seen in the
dash source:
The above logic was designed for running scripts automatically that lacked
the "#!" header, not to re-try failed recursion. On a legitimate -ENOEXEC,
things continue to behave as the shell expects.
Additionally, when tracking recursion, the binfmt handlers should not be
involved. The recursion being tracked is the depth of calls through
search_binary_handler(), so that function should be exclusively responsible
for tracking the depth.
Signed-off-by: Kees Cook <keescook@chromium.org> Cc: halfdog <me@halfdog.net> Cc: P J P <ppandit@redhat.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Artem Bityutskiy [Tue, 18 Dec 2012 00:03:17 +0000 (16:03 -0800)]
proc: pid/status: show all supplementary groups
We display a list of supplementary group for each process in
/proc/<pid>/status. However, we show only the first 32 groups, not all of
them.
Although this is rare, but sometimes processes do have more than 32
supplementary groups, and this kernel limitation breaks user-space apps
that rely on the group list in /proc/<pid>/status.
Number 32 comes from the internal NGROUPS_SMALL macro which defines the
length for the internal kernel "small" groups buffer. There is no
apparent reason to limit to this value.
This patch removes the 32 groups printing limit.
The Linux kernel limits the amount of supplementary groups by NGROUPS_MAX,
which is currently set to 65536. And this is the maximum count of groups
we may possibly print.
Kees Cook [Tue, 18 Dec 2012 00:03:14 +0000 (16:03 -0800)]
/proc/pid/status: add "Seccomp" field
It is currently impossible to examine the state of seccomp for a given
process. While attaching with gdb and attempting "call
prctl(PR_GET_SECCOMP,...)" will work with some situations, it is not
reliable. If the process is in seccomp mode 1, this query will kill the
process (prctl not allowed), if the process is in mode 2 with prctl not
allowed, it will similarly be killed, and in weird cases, if prctl is
filtered to return errno 0, it can look like seccomp is disabled.
When reviewing the state of running processes, there should be a way to
externally examine the seccomp mode. ("Did this build of Chrome end up
using seccomp?" "Did my distro ship ssh with seccomp enabled?")
This adds the "Seccomp" line to /proc/$pid/status.
Signed-off-by: Kees Cook <keescook@chromium.org> Reviewed-by: Cyrill Gorcunov <gorcunov@openvz.org> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: James Morris <jmorris@namei.org> Acked-by: Serge E. Hallyn <serge.hallyn@ubuntu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Cyrill Gorcunov [Tue, 18 Dec 2012 00:03:13 +0000 (16:03 -0800)]
procfs: add VmFlags field in smaps output
During c/r sessions we've found that there is no way at the moment to
fetch some VMA associated flags, such as mlock() and madvise().
This leads us to a problem -- we don't know if we should call for mlock()
and/or madvise() after restore on the vma area we're bringing back to
life.
This patch intorduces a new field into "smaps" output called VmFlags,
where all set flags associated with the particular VMA is shown as two
letter mnemonics.
[ Strictly speaking for c/r we only need mlock/madvise bits but it has been
said that providing just a few flags looks somehow inconsistent. So all
flags are here now. ]
This feature is made available on CONFIG_CHECKPOINT_RESTORE=n kernels, as
other applications may start to use these fields.
The data is encoded in a somewhat awkward two letters mnemonic form, to
encourage userspace to be prepared for fields being added or removed in
the future.
[a.p.zijlstra@chello.nl: props to use for_each_set_bit]
[sfr@canb.auug.org.au: props to use array instead of struct]
[akpm@linux-foundation.org: overall redesign and simplification]
[akpm@linux-foundation.org: remove unneeded braces per sfr, avoid using bloaty for_each_set_bit()] Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org> Cc: Pavel Emelyanov <xemul@parallels.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
I suggest to hide non-existent capabilities. Here is two reasons.
* It's logically and easier for using.
* It helps to checkpoint-restore capabilities of tasks, because tasks
can be restored on another kernel, where CAP_LAST_CAP is bigger.
Signed-off-by: Andrew Vagin <avagin@openvz.org> Cc: Andrew G. Morgan <morgan@kernel.org> Reviewed-by: Serge E. Hallyn <serge.hallyn@canonical.com> Cc: Pavel Emelyanov <xemul@parallels.com> Reviewed-by: Kees Cook <keescook@chromium.org> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: James Morris <jmorris@namei.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Oleg Nesterov [Tue, 18 Dec 2012 00:03:07 +0000 (16:03 -0800)]
ptrace: introduce PTRACE_O_EXITKILL
Ptrace jailers want to be sure that the tracee can never escape
from the control. However if the tracer dies unexpectedly the
tracee continues to run in potentially unsafe mode.
Add the new ptrace option PTRACE_O_EXITKILL. If the tracer exits
it sends SIGKILL to every tracee which has this bit set.
Note that the new option is not equal to the last-option << 1. Because
currently all options have an event, and the new one starts the eventless
group. It uses the random 20 bit, so we have the room for 12 more events,
but we can also add the new eventless options below this one.
Suggested by Amnon Shiloh.
Signed-off-by: Oleg Nesterov <oleg@redhat.com> Tested-by: Amnon Shiloh <u3557@miso.sublimeip.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Michael Kerrisk <mtk.manpages@gmail.com> Cc: Serge Hallyn <serge.hallyn@canonical.com> Cc: Chris Evans <scarybeasts@gmail.com> Cc: David Howells <dhowells@redhat.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Eldad Zack [Tue, 18 Dec 2012 00:03:04 +0000 (16:03 -0800)]
kstrto*: add documentation
As Bruce Fields pointed out, kstrto* is currently lacking kerneldoc
comments. This patch adds kerneldoc comments to common variants of
kstrto*: kstrto(u)l, kstrto(u)ll and kstrto(u)int.
Signed-off-by: Eldad Zack <eldad@fogrefinery.com> Cc: J. Bruce Fields <bfields@fieldses.org> Cc: Joe Perches <joe@perches.com> Cc: Randy Dunlap <rdunlap@xenotime.net> Cc: Alexey Dobriyan <adobriyan@gmail.com> Cc: Rob Landley <rob@landley.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Dave Reisner [Tue, 18 Dec 2012 00:03:01 +0000 (16:03 -0800)]
fs/fat: strip "cp" prefix from codepage in display
Option parsing code expects an unsigned integer for the codepage option,
but prefixes and stores this option with "cp" before passing to
load_nls(). This makes the displayed option in /proc an invalid one.
Strip the prefix when printing so that the displayed option is valid for
reuse.
Signed-off-by: Dave Reisner <dreisner@archlinux.org> Acked-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Jan Kara [Tue, 18 Dec 2012 00:02:59 +0000 (16:02 -0800)]
fat: ix mount option parsing
parse_options() is supposed to return value < 0 on error however we
returned 0 (success) in a lot of cases. This actually was not a problem
in practice because match_token() used by parse_options() is clever and
catches most of the problems for us.
Signed-off-by: Jan Kara <jack@suse.cz> Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Jan Kara [Tue, 18 Dec 2012 00:02:58 +0000 (16:02 -0800)]
fat: provide option for setting timezone offset
So far FAT either offsets time stamps by sys_tz.minuteswest or leaves them
as they are (when tz=UTC mount option is used). However in some cases it
is useful if one can specify time stamp offset on his own (e.g. when time
zone of the camera connected is different from time zone of the computer,
or when HW clock is in UTC and thus sys_tz.minuteswest == 0).
So provide a mount option time_offset= which allows user to specify offset
in minutes that should be applied to time stamps on the filesystem.
akpm: this code would work incorrectly when used via `mount -o remount',
because cached inodes would not be updated. But fatfs's fat_remount() is
basically a no-op anyway.
Signed-off-by: Jan Kara <jack@suse.cz> Acked-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Kim, Milo [Tue, 18 Dec 2012 00:02:51 +0000 (16:02 -0800)]
drivers/rtc/rtc-tps65910.c: enable RTC power domain on initialization
Enabling RTC HW block depends on the default value of TPS65910 register.
In some mode, RTC block is disabled by default.(eg. AM3517 Craneboard) In
this case, RTC_PWDN(RTC power down) bit should be cleared to enable the
RTC HW block.
This patch also works in case that RTC block is active by default, because
there is no side effect even if the bit is updated again.
Tested on AM3517 Craneboard.
Signed-off-by: Milo(Woogyom) Kim <milo.kim@ti.com> Acked-by: Venu Byravarasu <vbyravarasu@nvidia.com> Cc: Samuel Ortiz <sameo@linux.intel.com> Cc: Sivaram Nair <sivaramn@nvidia.com> Cc: Alessandro Zummo <a.zummo@towertech.it> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Tushar Behera [Tue, 18 Dec 2012 00:02:48 +0000 (16:02 -0800)]
drivers/rtc/rtc-s3c.c: convert to use devm_* API
rtc-s3c driver is modified to use devm_request_and_ioremap() (combining
request_mem_region and ioremap), devm_clk_get() and devm_request_irq()
APIs. Since this removes the necessity of freeing the related resources
the return path is also simplified.
Signed-off-by: Tushar Behera <tushar.behera@linaro.org> Cc: Alessandro Zummo <a.zummo@towertech.it> Cc: Grant Likely <grant.likely@secretlab.ca> Cc: Rob Herring <rob.herring@calxeda.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Thierry Reding [Tue, 18 Dec 2012 00:02:44 +0000 (16:02 -0800)]
rtc: add NXP PCF8523 support
Add an RTC driver for PCF8523 chips by NXP Semiconductors. No support is
currently provided for the alarm and interrupt functions. Only the time
and date functionality is implemented.
Deepak Sikri [Tue, 18 Dec 2012 00:02:34 +0000 (16:02 -0800)]
rtc: rtc-spear: Provide flag for no support of UIE mode
The applications can set the RTC hardware to trigger interrupts in one
of three modes:
* AIE: Alarm interrupt
* UIE: Update interrupt (ie: once per second)
* PIE: Periodic interrupt (sub-second irqs)
The above defined 3 modes are to be supported in the RTC HW in form of
interrupts. The SPEAr RTC hardware does not support the later two modes.
There have been refinements in the RTC core in mainline related to
use of timer queue infrastructure to manage events in RTC. Please refer
the below mentioned patch for details:
* RTC: Rework RTC code to use timerqueue for events
* SHA ID: 6610e0893b8bc6f59b14fed7f089c5997f035f88
There have been provisions added to support hardware that do not have
support the UIE mode. Please refer the following patch.
* rtc: Provide flag for rtc devices that don't support UIE
* SHA ID: 4a649903f91232d02284d53724b0a45728111767
The patch makes use of the provision defined in the above patch to
update the hardware status of UIE mode.
projects / linux-beck.git / log