Commit Graph

310471 Commits

Author SHA1 Message Date
Andrei Emeltchenko
4f42a8cd49 Bluetooth: trivial: Remove empty line
Signed-off-by: Andrei Emeltchenko <andrei.emeltchenko@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2012-06-05 06:34:07 +03:00
Andrei Emeltchenko
5325e5bb86 Bluetooth: Preserve L2CAP flags values
Previous callers of l2cap_build_conf_rsp in l2cap_config_req use
flags instead of continuation flag hardcoded value. It does not change
logic and preserve future possible flags.

Signed-off-by: Andrei Emeltchenko <andrei.emeltchenko@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2012-06-05 06:34:07 +03:00
Andrei Emeltchenko
9b3b44604a Bluetooth: Use defined link key size
Remove magic number with defined link key size.

Signed-off-by: Andrei Emeltchenko <andrei.emeltchenko@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2012-06-05 06:34:06 +03:00
Szymon Janc
a6c511c636 Bluetooth: Rename HCI_QUIRK_NO_RESET to HCI_QUIRK_RESET_ON_CLOSE
HCI_QUIRK_NO_RESET name is misleading - purpose of this quirk is to
reset device on close instead of init, not to not reset at all.
Rename it to HCI_QUIRK_RESET_ON_CLOSE to avoid confusion.

Signed-off-by: Szymon Janc <szymon.janc@tieto.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2012-06-05 06:34:06 +03:00
Gustavo Padovan
38351c66e4 Bluetooth: Fix trailing whitespaces in license text
As reported by checkpatch.pl

Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2012-06-05 06:34:06 +03:00
Gustavo Padovan
d660366d53 Bluetooth: Remove dead int returns
These functions were returning always 0, we just make then void.

Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
Reviewed-by: Mat Martineau <mathewm@codeaurora.org>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2012-06-05 06:34:06 +03:00
Gustavo Padovan
be4aad05af Bluetooth: Remove double check for BT_CONNECTED
The same check is done just before call l2cap_streaming_send()

Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
Reviewed-by: Mat Martineau <mathewm@codeaurora.org>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2012-06-05 06:34:06 +03:00
Andrei Emeltchenko
401bb1f768 Bluetooth: Silent sparse warnings
Silence warnings below:

net/bluetooth/l2cap_core.c:1662:24: warning: Using plain integer
as NULL pointer
net/bluetooth/l2cap_core.c:1662:27: warning: Using plain integer
as NULL pointer
net/bluetooth/l2cap_core.c:1683:24: warning: Using plain integer
as NULL pointer
net/bluetooth/l2cap_core.c:1683:27: warning: Using plain integer
as NULL pointer
net/bluetooth/l2cap_core.c:2260:46: warning: Using plain integer
as NULL pointer
net/bluetooth/l2cap_core.c:2574:33: warning: Using plain integer
as NULL pointer
net/bluetooth/l2cap_core.c:2581:33: warning: Using plain integer
as NULL pointer
net/bluetooth/l2cap_core.c:4556:24: warning: Using plain integer
as NULL pointer
net/bluetooth/l2cap_core.c:4556:27: warning: Using plain integer
as NULL pointer

Signed-off-by: Andrei Emeltchenko <andrei.emeltchenko@intel.com>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
2012-06-05 06:34:06 +03:00
Gustavo Padovan
ee556f662c Bluetooth: Do not purge queue in Basic Mode
chan->tx_q is only initialized if we use ERTM or Streaming mode.

Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2012-06-05 06:34:05 +03:00
Mat Martineau
d1de6d46dc Bluetooth: Enable ERTM by default
This enables the new receive and transmit state machines.

Signed-off-by: Mat Martineau <mathewm@codeaurora.org>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
2012-06-05 06:34:05 +03:00
Mat Martineau
522cc2ee6e Bluetooth: Remove unused ERTM control field macros
Now that l2cap_ctrl is used to set up control fields, these macros are
not needed.

Signed-off-by: Mat Martineau <mathewm@codeaurora.org>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
2012-06-05 06:34:05 +03:00
Mat Martineau
273759e2c3 Bluetooth: Set txwin values for streaming mode
The transmit window values must be configured for streaming mode, even
though streaming mode does not have a window.  This enables use of
extended headers when the transmit window socket option is set to 64
or larger.

Signed-off-by: Mat Martineau <mathewm@codeaurora.org>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
2012-06-05 06:34:05 +03:00
Mat Martineau
6ea0048575 Bluetooth: Remove unneccesary inline
Let the compiler decide if inlining is appropriate.

Signed-off-by: Mat Martineau <mathewm@codeaurora.org>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
2012-06-05 06:34:05 +03:00
Mat Martineau
0362520bf9 Bluetooth: Simplify the ERTM ack timeout
Since l2cap_send_ack can trigger extra actions like sending iframes,
don't call it.  Just send an RR or RNR frame if an ack needs sending.

Signed-off-by: Mat Martineau <mathewm@codeaurora.org>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
2012-06-05 06:34:05 +03:00
Mat Martineau
80909e04de Bluetooth: Use the ERTM transmit state machine from timeout handlers
Different states have different actions for retransmit and monitor
timeouts, so remove the logic for those actions from the timer handlers.

Signed-off-by: Mat Martineau <mathewm@codeaurora.org>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
2012-06-05 06:34:04 +03:00
Mat Martineau
4239d16f36 Bluetooth: Check rules when setting retransmit or monitor timers
The ERTM specification requires the retransmit timer to be cancelled
when the monitor timer is set.  The retransmit timer cannot be set
again while the monitor timer is pending.

Signed-off-by: Mat Martineau <mathewm@codeaurora.org>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
2012-06-05 06:34:04 +03:00
Mat Martineau
c9e3d5e004 Bluetooth: Use new header structures in l2cap_send_rr_or_rnr
struct l2cap_ctrl is now used, and the sframe is now sent directly
rather than depending on a separate call.

Signed-off-by: Mat Martineau <mathewm@codeaurora.org>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
2012-06-05 06:34:04 +03:00
Mat Martineau
fcd289df88 Bluetooth: Handle incoming REJ frames
REJ frames are sent by the remote device to request that all frames
after a given sequence number be retransmitted.  These are also an
implicit indication that the remote device is not in a busy state and
can receive new iframes.

Signed-off-by: Mat Martineau <mathewm@codeaurora.org>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
2012-06-05 06:34:04 +03:00
Mat Martineau
f80842a83e Bluetooth: Handle SREJ requests to resend unacked frames
When a remote device sends an SREJ, retransmit the frame with the
corresponding sequence number (subject to special cases with poll and
final flags).  An SREJ is also an implicit indication the the remote
device is not in a busy state.

Signed-off-by: Mat Martineau <mathewm@codeaurora.org>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
2012-06-05 06:34:04 +03:00
Mat Martineau
63838725c6 Bluetooth: Reassemble all available data when retransmissions succeed.
As retransmitted packets arrive, attempt to reassemble SDUs.  If all
requested retransmissions have been received, acknowledge them and
transition back to the RECV state.

Signed-off-by: Mat Martineau <mathewm@codeaurora.org>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
2012-06-05 06:34:04 +03:00
Mat Martineau
bed68bde7e Bluetooth: Send SREJ frames when packets go missing
The ERTM specification lays out three scenarios for sending SREJ
frames to request retransmission of specific frames.  l2cap_send_srej
requests all frames up to a given txseq that are not already queued
for reassembly.  l2cap_send_srej_tail only requests the most recent
missing frame.  l2cap_send_srej_list resends SREJ frames for data that
was requested for resend but never received.

Signed-off-by: Mat Martineau <mathewm@codeaurora.org>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
2012-06-05 06:34:04 +03:00
Mat Martineau
e1fbd4c19a Bluetooth: Add implementation for retransmitting all unacked frames
This adds l2cap_ertm_resend to retransmit frames based on the sequence
numbers in chan->retrans_list.  If the retransmit limit is reached for
any individual frame is reached, the connection is dropped.  skbs that
are cloned already are copied to avoid modifying shared data (this is
uncommon).  To retransmit all frames, l2cap_retransmit_all now builds
a list of all unacked sequence numbers and then calls
l2cap_ertm_resend.

Signed-off-by: Mat Martineau <mathewm@codeaurora.org>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
2012-06-05 06:34:03 +03:00
Mat Martineau
d2a7ac5d5d Bluetooth: Add the ERTM receive state machine
This adds a top-level state machine with handlers for two receive
states defined in the ERTM spec, RECV and SREJ_SENT.  The reqseq value
of the incoming frame is also validated at the top level and a
disconnection is forced if it is invalid.  The actions for the RECV
and SREJ_SENT states are implemented according to the state tables in
the ERTM specification.

Signed-off-by: Mat Martineau <mathewm@codeaurora.org>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
2012-06-05 06:34:03 +03:00
Mat Martineau
e31f763372 Bluetooth: Update l2cap_send_i_or_rr_or_rnr to fit the spec better
This action now exactly matches what is defined in the ERTM
specification, including clearing the remote busy flag and setting the
retransmit timer rather than retransmitting frames directly.  The spec
does not retransmit frames as part of this action, since
retransmission is only triggered by REJ, SREJ, or an RR with the final
bit set.  struct l2cap_ctrl is also used to set up header values.

Signed-off-by: Mat Martineau <mathewm@codeaurora.org>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
2012-06-05 06:34:03 +03:00
Mat Martineau
61aa4f5b9f Bluetooth: Use the transmit state machine for busy state changes
This lets the transmit state machine handle local busy state changes,
since different actions are taken in the different transmit states.

Signed-off-by: Mat Martineau <mathewm@codeaurora.org>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
2012-06-05 06:34:03 +03:00
Mat Martineau
0a0aba42b8 Bluetooth: Refactor l2cap_send_ack
The function now encapsulates more of the logic to either immediately
send an ack if the transmit window is over 75% full, or wait for the
ack timer to expire if the transmit window is not full enough.  It is
also able to push out waiting iframes that can carry an
acknowledgement.

Signed-off-by: Mat Martineau <mathewm@codeaurora.org>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
2012-06-05 06:34:03 +03:00
Mat Martineau
f5dbb0772d Bluetooth: Remove receive code that has been superceded
This deletes the receive code that had handlers for each frame type at
the top level, and then had logic to determine the receive state
within each handler.

Signed-off-by: Mat Martineau <mathewm@codeaurora.org>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
2012-06-05 06:34:03 +03:00
Mat Martineau
4b51dae967 Bluetooth: Add streaming mode receive and incoming packet classifier
Streaming mode reception is fairly simple, with in-sequence frames
being reassembled as they arrive.  Out-of-sequence frames are dropped,
and also clear any partially-assembled SDUs that may exist.

The packet classifier determines if the txseq value of the incoming
packet is expected, invalid (resulting in a disconnection), invalid
(ignorable), duplicate, or having to do with an SREJ request that was
previously sent.  The rules for each classification are defined in the
ERTM specification, and consolidating these rules in one place helps
clarify the receive state machine.

Signed-off-by: Mat Martineau <mathewm@codeaurora.org>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
2012-06-05 06:34:03 +03:00
Mat Martineau
cec8ab6e20 Bluetooth: Consolidate common receive code for ERTM and streaming mode
Creates a new l2cap_data_rcv function that combines previous code from
l2cap_ertm_data_rcv and l2cap_data_channel.  This reduces duplicate
code for streaming mode, and sets up a framework for the ERTM receive
state machine.

Signed-off-by: Mat Martineau <mathewm@codeaurora.org>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
2012-06-05 06:34:03 +03:00
Mat Martineau
a67d7f6fca Bluetooth: Refactor l2cap_send_sframe
The new implementation uses struct l2cap_ctrl to set up the sframe
fields, and also reduces duplicate acks by canceling the ack timer
whenever an RR or RNR frame is sent.  sframe PDU generation is also
split in to a separate function to separate it from the logic related
to the connection state and sframe type.

Signed-off-by: Mat Martineau <mathewm@codeaurora.org>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
2012-06-05 06:34:02 +03:00
Mat Martineau
18a48e7664 Bluetooth: Refactor l2cap_ertm_send
The new implementation is aware of the new transmit state machine, and
uses struct l2cap_ctrl to compose ERTM headers.  It also has improved
error handling for allocation failures, and does not send the packet
until after all skb and channel data structures are updated.

Signed-off-by: Mat Martineau <mathewm@codeaurora.org>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
2012-06-05 06:34:02 +03:00
Mat Martineau
3733937d96 Bluetooth: Refactor l2cap_streaming_send
This new implementation uses struct l2cap_ctrl to compose the
streaming mode headers.

Signed-off-by: Mat Martineau <mathewm@codeaurora.org>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
2012-06-05 06:34:02 +03:00
Mat Martineau
608bcc6d70 Bluetooth: Add a new L2CAP ERTM transmit state machine.
This implements a top-level transmit state machine with handlers for
the two ERTM states defined in the specification: XMIT and WAIT_F.

The state machine accepts an event and, optionally, a list of skbs to
transmit.  In addition to data transmission, the local busy state can
be modified, acks are processed, and monitor and retransmit timeouts
are handled.  This mirrors the structure of the state tables in the
spec.

Signed-off-by: Mat Martineau <mathewm@codeaurora.org>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
2012-06-05 06:34:02 +03:00
Mat Martineau
b191e031b7 Bluetooth: Change default state of ERTM disable flag
This is to allow for ERTM state machine replacement in the patches
that follow.

Signed-off-by: Mat Martineau <mathewm@codeaurora.org>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
2012-06-05 06:34:02 +03:00
Mat Martineau
2827011f66 Bluetooth: Fix early return from l2cap_chan_del
This fixes a regression from commit
2ead70b839 that is present in all
kernels starting at v3.0.

When L2CAP information was moved to struct l2cap_chan, a check was
added to l2cap_chan_del to avoid certain cleanup operations when ERTM
or streaming mode had not yet been initialized.  The logic in the
check did not take in to account that chan->conf_state is set to 0 in
l2cap_chan_ready, so l2cap_chan_del failed to cancel timers and leaked
memory any time the ERTM queues or lists were not empty.

This change makes sure that l2cap_chan_del only returns early if
ERTM initialization was not performed.

Signed-off-by: Mat Martineau <mathewm@codeaurora.org>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2012-06-05 06:34:02 +03:00
Mat Martineau
9dc9affcb7 Bluetooth: Free allocated ERTM SREJ list if init fails
If the ERTM SREJ list is properly allocated but the retransmit list
allocation fails, the SREJ list must be freed before returning from
l2cap_ertm_init.  l2cap_chan_del will not clean up the SREJ list
if l2cap_ertm_init returns a failure code.

Signed-off-by: Mat Martineau <mathewm@codeaurora.org>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2012-06-05 06:34:02 +03:00
Gustavo Padovan
a8c5fb1afe Bluetooth: Fix coding style in hci_core.c
Follow net subsystem rules.

Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2012-06-05 06:34:01 +03:00
Gustavo Padovan
5974e4c469 Bluetooth: Fix coding style in hci_conn.c
Follow net subsystem rules.

Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2012-06-05 06:34:01 +03:00
Gustavo Padovan
807deac275 Bluetooth: Fix coding style in hci_event.c
Follow the net subsystem rules.

Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2012-06-05 06:34:01 +03:00
Gustavo Padovan
b80f021f70 Bluetooth: Fix coding style in hci_sysfs.c
Follow the net subsystem rules.

Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2012-06-05 06:34:01 +03:00
Gustavo Padovan
3bb3c7551c Bluetooth: Fix coding style in hci_sock.c
Follow the net subsystem rules.

Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2012-06-05 06:34:01 +03:00
Gustavo Padovan
be7c2b99e9 Bluetooth: Fix coding style in sco.c
Follow the net subsystem rules.

Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2012-06-05 06:34:01 +03:00
Gustavo Padovan
8ce8e2b56f Bluetooth: Fix coding style in mgmt.c
Follow the coding style of the net subsystem.

Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2012-06-05 06:34:01 +03:00
Linus Torvalds
f8f5701bda Linux 3.5-rc1 2012-06-02 18:29:26 -07:00
Linus Torvalds
912afc3616 Improve multipath's retrying mechanism in some defined circumstances
and provide a simple reserve/release mechanism for userspace tools to
 access thin provisioning metadata while the pool is in use.
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Merge tag 'dm-3.5-changes-1' of git://git.kernel.org/pub/scm/linux/kernel/git/agk/linux-dm

Pull device-mapper updates from Alasdair G Kergon:
 "Improve multipath's retrying mechanism in some defined circumstances
  and provide a simple reserve/release mechanism for userspace tools to
  access thin provisioning metadata while the pool is in use."

* tag 'dm-3.5-changes-1' of git://git.kernel.org/pub/scm/linux/kernel/git/agk/linux-dm:
  dm thin: provide userspace access to pool metadata
  dm thin: use slab mempools
  dm mpath: allow ioctls to trigger pg init
  dm mpath: delay retry of bypassed pg
  dm mpath: reduce size of struct multipath
2012-06-02 17:39:40 -07:00
Joe Thornber
cc8394d86f dm thin: provide userspace access to pool metadata
This patch implements two new messages that can be sent to the thin
pool target allowing it to take a snapshot of the _metadata_.  This,
read-only snapshot can be accessed by userland, concurrently with the
live target.

Only one metadata snapshot can be held at a time.  The pool's status
line will give the block location for the current msnap.

Since version 0.1.5 of the userland thin provisioning tools, the
thin_dump program displays the msnap as follows:

    thin_dump -m <msnap root> <metadata dev>

Available here: https://github.com/jthornber/thin-provisioning-tools

Now that userland can access the metadata we can do various things
that have traditionally been kernel side tasks:

     i) Incremental backups.

     By using metadata snapshots we can work out what blocks have
     changed over time.  Combined with data snapshots we can ensure
     the data doesn't change while we back it up.

     A short proof of concept script can be found here:

     https://github.com/jthornber/thinp-test-suite/blob/master/incremental_backup_example.rb

     ii) Migration of thin devices from one pool to another.

     iii) Merging snapshots back into an external origin.

     iv) Asyncronous replication.

Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2012-06-03 00:30:01 +01:00
Mike Snitzer
a24c25696b dm thin: use slab mempools
Use dedicated caches prefixed with a "dm_" name rather than relying on
kmalloc mempools backed by generic slab caches so the memory usage of
thin provisioning (and any leaks) can be accounted for independently.

Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2012-06-03 00:30:00 +01:00
Mikulas Patocka
35991652ba dm mpath: allow ioctls to trigger pg init
After the failure of a group of paths, any alternative paths that
need initialising do not become available until further I/O is sent to
the device.  Until this has happened, ioctls return -EAGAIN.

With this patch, new paths are made available in response to an ioctl
too.  The processing of the ioctl gets delayed until this has happened.

Instead of returning an error, we submit a work item to kmultipathd
(that will potentially activate the new path) and retry in ten
milliseconds.

Note that the patch doesn't retry an ioctl if the ioctl itself fails due
to a path failure.  Such retries should be handled intelligently by the
code that generated the ioctl in the first place, noting that some SCSI
commands should not be retried because they are not idempotent (XOR write
commands).  For commands that could be retried, there is a danger that
if the device rejected the SCSI command, the path could be errorneously
marked as failed, and the request would be retried on another path which
might fail too.  It can be determined if the failure happens on the
device or on the SCSI controller, but there is no guarantee that all
SCSI drivers set these flags correctly.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2012-06-03 00:29:58 +01:00
Mike Christie
f220fd4efb dm mpath: delay retry of bypassed pg
If I/O needs retrying and only bypassed priority groups are available,
set the pg_init_delay_retry flag to wait before retrying.

If, for example, the reason for the bypass is that the controller is
getting reset or there is a firmware upgrade happening, retrying right
away would cause a flood of log messages and retries for what could be a
few seconds or even several minutes.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Acked-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2012-06-03 00:29:45 +01:00
Mike Snitzer
1fbdd2b3a3 dm mpath: reduce size of struct multipath
Move multipath structure's 'lock' and 'queue_size' members to eliminate
two 4-byte holes.  Also use a bit within a single unsigned int for each
existing flag (saves 8-bytes).  This allows future flags to be added
without each consuming an unsigned int.

Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Acked-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2012-06-03 00:29:43 +01:00