Remove now unnecessary inclusions of {asm,linux}/a.out.h.

[akpm@linux-foundation.org: fix alpha build]
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Signed-off-by: NAlan Cox <alan@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Signed-off-by: NAlan Cox <alan@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Signed-off-by: NAlan Cox <alan@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Signed-off-by: NAlan Cox <alan@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Signed-off-by: NAlan Cox <alan@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Signed-off-by: NAlan Cox <alan@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Signed-off-by: NAlan Cox <alan@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Signed-off-by: NAlan Cox <alan@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Signed-off-by: NAlan Cox <alan@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Signed-off-by: NAlan Cox <alan@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Signed-off-by: NAlan Cox <alan@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Signed-off-by: NAlan Cox <alan@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Also removes a cflag comparison that caused some mode changes to get wrongly
ignored
Signed-off-by: NAlan Cox <alan@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Signed-off-by: NAlan Cox <alan@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Signed-off-by: NAlan Cox <alan@redhat.com>
Cc: Jiri Slaby <jirislaby@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Fix an off by one bug in the fault reason string reporting function, and
clean up some of the code around this buglet.

[akpm@linux-foundation.org: cleanup]
Signed-off-by: Nmark gross <mgross@linux.intel.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Add support for protected memory enable bits by clearing them if they are
set at startup time.  Some future boot loaders or firmware could have this
bit set after it loads the kernel, and it needs to be cleared if DMA's are
going to happen effectively.
Signed-off-by: Nmark gross <mgross@intel.com>
Acked-by: NMuli Ben-Yehuda <muli@il.ibm.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Signed-off-by: NNick Piggin <npiggin@suse.de>
Cc: Douglas Gilbert <dougg@torque.net>
Cc: James Bottomley <James.Bottomley@steeleye.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This patch adds extra information to the mirror status output, so that
it can be determined which device(s) have failed.  For each mirror device,
a character is printed indicating the most severe error encountered.  The
characters are:
 *    A => Alive - No failures
 *    D => Dead - A write failure occurred leaving mirror out-of-sync
 *    S => Sync - A sychronization failure occurred, mirror out-of-sync
 *    R => Read - A read failure occurred, mirror data unaffected
This allows userspace to properly reconfigure the mirror set.
Signed-off-by: NJonathan Brassow <jbrassow@redhat.com>
Signed-off-by: NAlasdair G Kergon <agk@redhat.com>

This patch gives the ability to respond-to/record device failures
that happen during read operations.  It also adds the ability to
read from mirror devices that are not the primary if they are
in-sync.

There are essentially two read paths in mirroring; the direct path
and the queued path.  When a read request is mapped, if the region
is 'in-sync' the direct path is taken; otherwise the queued path
is taken.

If the direct path is taken, we must record bio information so that
if the read fails we can retry it.  We then discover the status of
a direct read through mirror_end_io.  If the read has failed, we will
mark the device from which the read was attempted as failed (so we
don't try to read from it again), restore the bio and try again.

If the queued path is taken, we discover the results of the read
from 'read_callback'.  If the device failed, we will mark the device
as failed and attempt the read again if there is another device
where this region is known to be 'in-sync'.
Signed-off-by: NJonathan Brassow <jbrassow@redhat.com>
Signed-off-by: NAlasdair G Kergon <agk@redhat.com>

This patch adds the ability to requeue write I/O to
core device-mapper when there is a log device failure.

If a write to the log produces and error, the pending writes are
put on the "failures" list.  Since the log is marked as failed,
they will stay on the failures list until a suspend happens.

Suspends come in two phases, presuspend and postsuspend.  We must
make sure that all the writes on the failures list are requeued
in the presuspend phase (a requirement of dm core).  This means
that recovery must be complete (because writes may be delayed
behind it) and the failures list must be requeued before we
return from presuspend.

The mechanisms to ensure recovery is complete (or stopped) was
already in place, but needed to be moved from postsuspend to
presuspend.  We rely on 'flush_workqueue' to ensure that the
mirror thread is complete and therefore, has requeued all writes
in the failures list.

Because we are using flush_workqueue, we must ensure that no
additional 'queue_work' calls will produce additional I/O
that we need to requeue (because once we return from
presuspend, we are unable to do anything about it).  'queue_work'
is called in response to the following functions:
- complete_resync_work = NA, recovery is stopped
- rh_dec (mirror_end_io) = NA, only calls 'queue_work' if it
                           is ready to recover the region
                           (recovery is stopped) or it needs
                           to clear the region in the log*
                           **this doesn't get called while
                           suspending**
- rh_recovery_end = NA, recovery is stopped
- rh_recovery_start = NA, recovery is stopped
- write_callback = 1) Writes w/o failures simply call
                   bio_endio -> mirror_end_io -> rh_dec
                   (see rh_dec above)
                   2) Writes with failures are put on
                   the failures list and queue_work is
                   called**
                   ** write_callbacks don't happen
                   during suspend **
- do_failures = NA, 'queue_work' not called if suspending
- add_mirror (initialization) = NA, only done on mirror creation
- queue_bio = NA, 1) delayed I/O scheduled before flush_workqueue
              is called.  2) No more I/Os are being issued.
              3) Re-attempted READs can still be handled.
              (Write completions are handled through rh_dec/
              write_callback - mention above - and do not
              use queue_bio.)
Signed-off-by: NJonathan Brassow <jbrassow@redhat.com>
Signed-off-by: NAlasdair G Kergon <agk@redhat.com>

This patch adds the calls to 'fail_mirror' if an error occurs during
mirror recovery (aka resynchronization).  'fail_mirror' is responsible
for recording the type of error by mirror device and ensuring an event
gets raised for the purpose of notifying userspace.
Signed-off-by: NJonathan Brassow <jbrassow@redhat.com>
Signed-off-by: NAlasdair G Kergon <agk@redhat.com>

This patch gives mirror the ability to handle device failures
during normal write operations.

The 'write_callback' function is called when a write completes.
If all the writes failed or succeeded, we report failure or
success respectively.  If some of the writes failed, we call
fail_mirror; which increments the error count for the device, notes
the type of error encountered (DM_RAID1_WRITE_ERROR),  and
selects a new primary (if necessary).  Note that the primary
device can never change while the mirror is not in-sync (IOW,
while recovery is happening.)  This means that the scenario
where a failed write changes the primary and gives
recovery_complete a chance to misread the primary never happens.
The fact that the primary can change has necessitated the change
to the default_mirror field.  We need to protect against reading
garbage while the primary changes.  We then add the bio to a new
list in the mirror set, 'failures'.  For every bio in the 'failures'
list, we call a new function, '__bio_mark_nosync', where we mark
the region 'not-in-sync' in the log and properly set the region
state as, RH_NOSYNC.  Userspace must also be notified of the
failure.  This is done by 'raising an event' (dm_table_event()).
If fail_mirror is called in process context the event can be raised
right away.  If in interrupt context, the event is deferred to the
kmirrord thread - which raises the event if 'event_waiting' is set.

Backwards compatibility is maintained by ignoring errors if
the DM_FEATURES_HANDLE_ERRORS flag is not present.
Signed-off-by: NJonathan Brassow <jbrassow@redhat.com>
Signed-off-by: NAlasdair G Kergon <agk@redhat.com>

Provided sector_t is 64 bits, reduce the in-memory footprint of the
snapshot exception table by the simple method of using unused bits of
the chunk number to combine consecutive entries.
Signed-off-by: NMilan Broz <mbroz@redhat.com>
Signed-off-by: NAlasdair G Kergon <agk@redhat.com>

This patch adds additional information to the status line. It is added at the
end of the returned text so it will not interfere with existing
implementations using this data. The addition of this information will allow
for a common return interface to match that returned with the dm-raid1.c
status line (with Jonathan Brassow's patches).

Here is a sample of what is returned with a mirror "status" call:
isw_eeaaabgfg_mirror: 0 488390920 mirror 2 8:16 8:32 3727/3727 1 AA 1 core

Here's what's returned with this patch for a stripe "status" call:
isw_dheeijjdej_stripe: 0 976783872 striped 2 8:16 8:32 1 AA
Signed-off-by: NBrian Wood <brian.j.wood@intel.com>
Signed-off-by: NAlasdair G Kergon <agk@redhat.com>

This patch adds the stripe_end_io function to process errors that might
occur after an IO operation. As part of this there are a number of
enhancements made to record and trigger events:

- New atomic variable in struct stripe to record the number of
errors each stripe volume device has experienced (could be used
later with uevents to report back directly to userspace)

- New workqueue/work struct setup to process the trigger_event function

- New end_io function. It is here that testing for BIO error conditions
take place. It determines the exact stripe that cause the error,
records this in the new atomic variable, and calls the queue_work() function

- New trigger_event function to process failure events. This
calls dm_table_event()
Signed-off-by: NBrian Wood <brian.j.wood@intel.com>
Signed-off-by: NAlasdair G Kergon <agk@redhat.com>

If the log type is not recognised, attempt to load the module
'dm-log-<type>.ko'.
Signed-off-by: NJonathan Brassow <jbrassow@redhat.com>
Signed-off-by: NAlasdair G Kergon <agk@redhat.com>

Add a single-thread workqueue for each mapped device
and move flushing of the lists of pushback and deferred bios
to this new workqueue.
Signed-off-by: NMilan Broz <mbroz@redhat.com>
Signed-off-by: NAlasdair G Kergon <agk@redhat.com>

dm-crypt: Use crypto ablkcipher interface

Move encrypt/decrypt core to async crypto call.
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: NMilan Broz <mbroz@redhat.com>
Signed-off-by: NAlasdair G Kergon <agk@redhat.com>

dm-crypt: Use crypto ablkcipher interface

Prepare callback function for async crypto operation.
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: NMilan Broz <mbroz@redhat.com>
Signed-off-by: NAlasdair G Kergon <agk@redhat.com>

dm-crypt: Use crypto ablkcipher interface
Prepare completion for async crypto request.
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: NMilan Broz <mbroz@redhat.com>
Signed-off-by: NAlasdair G Kergon <agk@redhat.com>

dm-crypt: Use crypto ablkcipher interface

Introduce mempool for async crypto requests.

cc->req is used mainly during synchronous operations
(to prevent allocation and deallocation of the same object).
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: NMilan Broz <mbroz@redhat.com>
Signed-off-by: NAlasdair G Kergon <agk@redhat.com>

dm-crypt: Use crypto ablkcipher interface

Move scatterlists to separate dm_crypt_struct and
pick out block processing from crypt_convert.
Signed-off-by: NMilan Broz <mbroz@redhat.com>
Signed-off-by: NAlasdair G Kergon <agk@redhat.com>

Make io reference counting more obvious.
Signed-off-by: NMilan Broz <mbroz@redhat.com>
Signed-off-by: NAlasdair G Kergon <agk@redhat.com>

Introduce crypt_write_io_loop().
Signed-off-by: NMilan Broz <mbroz@redhat.com>
Signed-off-by: NAlasdair G Kergon <agk@redhat.com>

Process write request in separate function and queue
final bio through io workqueue.
Signed-off-by: NMilan Broz <mbroz@redhat.com>
Signed-off-by: NAlasdair G Kergon <agk@redhat.com>

Add sector into dm_crypt_io instead of using local variable.
Signed-off-by: NMilan Broz <mbroz@redhat.com>
Signed-off-by: NAlasdair G Kergon <agk@redhat.com>

Reorder kcryptd functions for clarity.
Signed-off-by: NAlasdair G Kergon <agk@redhat.com>

Rename functions to follow calling convention.
Prepare write io error processing function skeleton.
Signed-off-by: NMilan Broz <mbroz@redhat.com>
Signed-off-by: NAlasdair G Kergon <agk@redhat.com>