set choose_first true for cluster read in read balance when the area
is resyncing.
Signed-off-by: NLidong Zhong <lzhong@suse.com>
Signed-off-by: NGoldwyn Rodrigues <rgoldwyn@suse.com>

If there is a resync going on, all nodes must suspend writes to the
range. This is recorded in the suspend_info/suspend_list.

If there is an I/O within the ranges of any of the suspend_info,
should_suspend will return 1.
Signed-off-by: NGoldwyn Rodrigues <rgoldwyn@suse.com>

When a RESYNC_START message arrives, the node removes the entry
with the current slot number and adds the range to the
suspend_list.

Simlarly, when a RESYNC_FINISHED message is received, node clears
entry with respect to the bitmap number.
Signed-off-by: NGoldwyn Rodrigues <rgoldwyn@suse.com>

When a resync is initiated, RESYNCING message is sent to all active
nodes with the range (lo,hi). When the resync is over, a RESYNCING
message is sent with (0,0). A high sector value of zero indicates
that the resync is over.
Signed-off-by: NGoldwyn Rodrigues <rgoldwyn@suse.com>

Re-reads the devices by invalidating the cache.
Since we don't write to faulty devices, this is detected using
events recorded in the devices. If it is old as compared to the mddev
mark it is faulty.
Signed-off-by: NGoldwyn Rodrigues <rgoldwyn@suse.com>

   - request to send a message
   - make changes to superblock
   - send messages telling everyone that the superblock has changed
   - other nodes all read the superblock
   - other nodes all ack the messages
   - updating node release the "I'm sending a message" resource.
Signed-off-by: NGoldwyn Rodrigues <rgoldwyn@suse.com>

The sending part is split in two functions to make sure
atomicity of the operations, such as the MD superblock update.
Signed-off-by: NLidong Zhong <lzhong@suse.com>
Signed-off-by: NGoldwyn Rodrigues <rgoldwyn@suse.com>

1. receive status

   sender                         receiver                   receiver
   ACK:CR                          ACK:CR                     ACK:CR

2. sender get EX of TOKEN
   sender get EX of MESSAGE
   sender                          receiver                   receiver
   TOKEN:EX                         ACK:CR                     ACK:CR
   MESSAGE:EX
   ACK:CR

3. sender write LVB.
   sender down-convert MESSAGE from EX to CR
   sender try to get EX of ACK
   [ wait until all receiver has *processed* the MESSAGE ]

                                     [ triggered by bast of ACK ]
                                     receiver get CR of MESSAGE
                                     receiver read LVB
                                     receiver processes the message
				     [ wait finish ]
                                     receiver release ACK

   sender                         receiver                   receiver
   TOKEN:EX                       MESSAGE:CR                 MESSAGE:CR
   MESSAGE:CR
   ACK:EX

4. sender down-convert ACK from EX to CR
   sender release MESSAGE
   sender release TOKEN
				  receiver upconvert to EX of MESSAGE
                                  receiver get CR of ACK
				  receiver release MESSAGE

   sender                        receiver                   receiver
   ACK:CR                         ACK:CR                     ACK:CR
Signed-off-by: NLidong Zhong <lzhong@suse.com>
Signed-off-by: NGoldwyn Rodrigues <rgoldwyn@suse.com>

If bitmap_copy_slot returns hi>0, we need to perform resync.
Signed-off-by: NGoldwyn Rodrigues <rgoldwyn@suse.com>

The DLM informs us in case of node failure with the DLM slot number.
cluster_info->recovery_map sets the bit corresponding to the slot number
and wakes up the recovery thread.

The recovery thread:
1. Derives the slot number from the recovery_map
2. Locks the bitmap corresponding to the slot
3. Copies the set bits to the node-local bitmap
Signed-off-by: NGoldwyn Rodrigues <rgoldwyn@suse.com>

bitmap_copy_from_slot reads the bitmap from the slot mentioned.
It then copies the set bits to the node local bitmap.

This is helper function for the resync operation on node failure.

bitmap_set_memory_bits() currently assumes it is only run at startup and that
they bitmap is currently empty.  So if it finds that a region is already
marked as dirty, it won't mark it dirty again. Change bitmap_set_memory_bits()
to always set the NEEDED_MASK bit if 'needed' is set.
Signed-off-by: NGoldwyn Rodrigues <rgoldwyn@suse.com>

This is done to have multiple bitmaps open at the same time.
Signed-off-by: NGoldwyn Rodrigues <rgoldwyn@suse.com>

When a node joins, it does not know of other nodes performing resync.
So, each node keeps the resync information in it's LVB. When a new
node joins, it reads the LVB of each "online" bitmap.

[TODO] The new node attempts to get the PW lock on other bitmap, if
it is successful, it reads the bitmap and performs the resync (if
required) on it's behalf.

If the node does not get the PW, it requests CR and reads the LVB
for the resync information.
Signed-off-by: NGoldwyn Rodrigues <rgoldwyn@suse.com>

Signed-off-by: NGoldwyn Rodrigues <rgoldwyn@suse.com>

On-disk format:

0                    4k                     8k                    12k
-------------------------------------------------------------------
| idle                | md super            | bm super [0] + bits |
| bm bits[0, contd]   | bm super[1] + bits  | bm bits[1, contd]   |
| bm super[2] + bits  | bm bits [2, contd]  | bm super[3] + bits  |
| bm bits [3, contd]  |                     |                     |

Bitmap super has a field nodes, which defines the maximum number
of nodes the device can use. While reading the bitmap super, if
the cluster finds out that the number of nodes is > 0:
1. Requests the md-cluster module.
2. Calls md_cluster_ops->join(), which sets up clustering such as
   joining DLM lockspace.

Since the first time, the first bitmap is read. After the call
to the cluster_setup, the bitmap offset is adjusted and the
superblock is re-read. This also ensures the bitmap is read
the bitmap lock (when bitmap lock is introduced in later patches)

Questions:
1. cluster name is repeated in all bitmap supers. Is that okay?
Signed-off-by: NGoldwyn Rodrigues <rgoldwyn@suse.com>

DLM offers callbacks when a node fails and the lock remastery
is performed:

1. recover_prep: called when DLM discovers a node is down
2. recover_slot: called when DLM identifies the node and recovery
		can start
3. recover_done: called when all nodes have completed recover_slot

recover_slot() and recover_done() are also called when the node joins
initially in order to inform the node with its slot number. These slot
numbers start from one, so we deduct one to make it start with zero
which the cluster-md code uses.
Signed-off-by: NGoldwyn Rodrigues <rgoldwyn@suse.com>

Signed-off-by: NGoldwyn Rodrigues <rgoldwyn@suse.com>

md_cluster_info stores the cluster information in the MD device.

The join() is called when mddev detects it is a clustered device.
The main responsibilities are:
	1. Setup a DLM lockspace
	2. Setup all initial locks such as super block locks and bitmap lock (will come later)

The leave() clears up the lockspace and all the locks held.
Signed-off-by: NGoldwyn Rodrigues <rgoldwyn@suse.com>

This allows dynamic registering of cluster hooks.
Signed-off-by: NGoldwyn Rodrigues <rgoldwyn@suse.com>

A dlm_lock_resource is a structure which contains all information
required for locking using DLM. The init function allocates the
lock and acquires the lock in NL mode. The unlock function
converts the lock resource to NL mode. This is done to preserve
LVB and for faster processing of locks. The lock resource is
DLM unlocked only in the lockres_free function, which is the end
of life of the lock resource.
Signed-off-by: NLidong Zhong <lzhong@suse.com>
Signed-off-by: NGoldwyn Rodrigues <rgoldwyn@suse.com>

Tagged as EXPERIMENTAL for now.
Signed-off-by: NGoldwyn Rodrigues <rgoldwyn@suse.com>

Signed-off-by: NGoldwyn Rodrigues <rgoldwyn@suse.com>

Upstream checkpatch now requires this.
Reviewed-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NMike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: NRoland Dreier <roland@purestorage.com>

Signed-off-by: NMike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: NRoland Dreier <roland@purestorage.com>

For, !HAVE_CLK the clk API returns a NULL cookie. Rework the
initialization code to handle that. If clk_get_rate() delivers 0, we use
the fallback mechanisms. The patch is pretty easy when ignoring white
space issues (git diff -b).
Suggested-by: NRussell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>
Tested-by: NMax Filippov <jcmvbkbc@gmail.com>

The exynos_tmu_data() function should on entrance test not only for valid
data pointer, but also for data->tmu_read one.
It is important, since afterwards it is dereferenced to get temperature code.
Signed-off-by: NLukasz Majewski <l.majewski@samsung.com>
Tested-by: NAbhilash Kesavan <a.kesavan@samsung.com>
Signed-off-by: NZhang Rui <rui.zhang@intel.com>

Code that does this:

	if (!(d_unhashed(tmp) && tmp->d_inode)) {
		...
		simple_unlink(parent->d_inode, tmp);
	}

is broken because:

	!(d_unhashed(tmp) && tmp->d_inode)

is equivalent to:

	!d_unhashed(tmp) || !tmp->d_inode

so it is possible to get into simple_unlink() with tmp->d_inode == NULL.

simple_unlink(), however, assumes tmp->d_inode cannot be NULL.

I think that what was meant is this:

	!d_unhashed(tmp) && tmp->d_inode

and that the logical-not operator or the final close-bracket was misplaced.
Signed-off-by: NDavid Howells <dhowells@redhat.com>
cc: Bryan O'Sullivan <bos@pathscale.com>
cc: Roland Dreier <rolandd@cisco.com>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

We don't really need to recalculate the effective rate of a clock when a
per-user clock is removed, if the constraints of the later aren't
limiting the requested rate.

This was causing problems with clocks that never had a rate set before,
as rate_req would be zero. Though this could be considered a bug in the
implementation of those clocks, this should be checked somewhere else.

Fixes: 1c8e6004 ("clk: Add rate constraints to clocks")
Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: Peter De Schrijver <pdeschrijver@nvidia.com>
Signed-off-by: NTomeu Vizoso <tomeu.vizoso@collabora.com>
Signed-off-by: NMichael Turquette <mturquette@linaro.org>

From a locking point of view it is safe to check waiting_msg without
a lock, but there is a memory ordering issue that causes it to
possibly not be set right when viewed from another processor.  We are
already claiming a lock right after that, move the check to inside
the lock to enforce the memory ordering.
Signed-off-by: NCorey Minyard <cminyard@mvista.com>

The seq_printf like functions will soon be changed to return void.

Convert these uses to check seq_has_overflowed instead.
Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NCorey Minyard <cminyard@mvista.com>

Instead of manual calls of device_create_file() and
device_remove_file(), implement the condition in is_visible callback
for the attribute group and put these entries to the group, too.
This simplifies the code and avoids the possible races.
Signed-off-by: NTakashi Iwai <tiwai@suse.de>
Signed-off-by: NCorey Minyard <cminyard@mvista.com>

This adds a loop through the elements in the linked list, recv_msgs using
list_for_entry_safe in order to free messages in this list.  In addition
we are using the safe version of this marco in order to prevent use after
bugs related to deleting the element we are on currently by holding a
pointer to the next element after the current one we are on and freeing
with the function, ipmi_free_recv_msg internally in this loop.
Signed-off-by: NNicholas Krause <xerofoify@gmail.com>
Signed-off-by: NCorey Minyard <cminyard@mvista.com>

A new harmless warning has come up on ARM builds with gcc-4.9:

drivers/char/ipmi/ipmi_msghandler.c: In function 'smi_send.isra.11':
include/linux/spinlock.h:372:95: warning: 'flags' may be used uninitialized in this function [-Wmaybe-uninitialized]
  raw_spin_unlock_irqrestore(&lock->rlock, flags);
                                                                                               ^
drivers/char/ipmi/ipmi_msghandler.c:1490:16: note: 'flags' was declared here
  unsigned long flags;
                ^

This could be worked around by initializing the 'flags' variable, but it
seems better to rework the code to avoid this.
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Fixes: 7ea0ed2b ("ipmi: Make the message handler easier to use for SMI interfaces")
Signed-off-by: NCorey Minyard <cminyard@mvista.com>

As part of the internal y2038 cleanup, this patch removes
timespec usage in the ipmi driver, replacing it timespec64

Cc: openipmi-developer@lists.sourceforge.net
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: NJohn Stultz <john.stultz@linaro.org>
Signed-off-by: NCorey Minyard <minyard@mvista.com>

The driver uses #ifdef DEBUG_TIMING in order to conditionally print out
timestamped debug messages. Unfortunately it adds the ifdefs all over the
usage sites.

This patch cleans it up by adding a debug_timestamp() function which
is compiled out if DEBUG_TIMING isn't present. This cleans up all
the ugly ifdefs in the function logic.

Cc: openipmi-developer@lists.sourceforge.net
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: NJohn Stultz <john.stultz@linaro.org>
Signed-off-by: NCorey Minyard <minyard@mvista.com>

Removes a no longer needed FIXME comment in the function,acpi_gpe_irq_setup
for the file,ipmi_si_intf.c. This comment is no longer needed as clearly we
are passing the correct level of  ACPI_GPE_LEVEL_TRIGGERED to the installer
function,acpi_install_gpe_handler due to no breakage after years of using
this ACPI level in the function,acpi_install_gpe_handler.
Signed-off-by: NNicholas Krause <xerofoify@gmail.com>
Signed-off-by: NCorey Minyard <cminyard@mvista.com>

A few new i2c-drivers came into the kernel which clear the clientdata-pointer
on exit or error. This is obsolete meanwhile, the core will do it.
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>
Signed-off-by: NCorey Minyard <cminyard@mvista.com>

There can't be more than a few IPMI messages allocated at any one time,
so converting the messages to slabs would be a waste.  So just remove
the FIXME.
Suggested-by: NNicholas Krause <xerofoify@gmail.com>
Signed-off-by: NCorey Minyard <cminyard@mvista.com>

This makes all sync commands uninterruptible and schedules without timeout
so the controller either has to post a completion or the timeout recovery
fails the command. This fixes potential memory or data corruption from
a command timing out too early or woken by a signal. Previously any DMA
buffers mapped for that command would have been released even though we
don't know what the controller is planning to do with those addresses.
Signed-off-by: NKeith Busch <keith.busch@intel.com>

We don't track queues in a llist, subscribe to hot-cpu notifications,
or internally retry commands. Delete the unused artifacts.
Signed-off-by: NKeith Busch <keith.busch@intel.com>