The call to rh_in_sync() in do_reads() should be allowed to block.  It is in
the mirror worker thread which already permits blocking operations.  This will
be needed to support clustered mirroring which will perform network
operations.
Signed-off-by: NJonathan Brassow <jbrassow@redhat.com>
Signed-off-by: NAlasdair G Kergon <agk@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

With the code as it is, it is possible for oustanding clear region requests
never to get flushed when a mirror is deactivated or suspended.  This means
there will always be some resync work required when a mirror is activated,
even though it may very well be in-sync.

Always requesting the flush doesn't hurt us.  This is because the log tracks
whether any changes occurred and, if not, no flush is performed.
Signed-off-by: NJonathan Brassow <jbrassow@redhat.com>
Signed-off-by: NAlasdair G Kergon <agk@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

New device-mapper target that can delay I/O (for testing).  Reads can be
separated from writes, redirected to different underlying devices and delayed
by differing amounts of time.
Signed-off-by: NHeinz Mauelshagen <mauelshagen@redhat.com>
Signed-off-by: NMilan Broz <mbroz@redhat.com>
Signed-off-by: NAlasdair G Kergon <agk@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

More bio_list helper functions for new targets (including dm-delay and
dm-loop) to manipulate lists of bios.
Signed-off-by: NHeinz Mauelshagen <hjm@redhat.com>
Signed-off-by: NBryn Reeves <breeves@redhat.com>
Signed-off-by: NMilan Broz <mbroz@redhat.com>
Signed-off-by: NAlasdair G Kergon <agk@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Remove old dm-io interface.
Signed-off-by: NMilan Broz <mbroz@redhat.com>
Signed-off-by: NAlasdair G Kergon <agk@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This patch ports dm-raid1.c to the new dm-io interface.
Signed-off-by: NMilan Broz <mbroz@redhat.com>
Signed-off-by: NAlasdair G Kergon <agk@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This patch ports dm-log.c to the new dm-io interface in order to make it
scalable to have a large number of persistent dirty logs active in parallel.
Signed-off-by: NHeinz Mauelshagen <heinzm@redhat.com>
Cc: Milan Broz <mbroz@redhat.com>
Signed-off-by: NAlasdair G Kergon <agk@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This patch ports dm-exception-store.c to the new, scalable dm_io() interface.

It replaces dm_io_get()/dm_io_put() by
dm_io_client_create()/dm_io_client_destroy() calls and
dm_io_sync_vm() by dm_io() to achive this.
Signed-off-by: NHeinz Mauelshagen <hjm@redhat.com>
Cc: Milan Broz <mbroz@redhat.com>
Signed-off-by: NAlasdair G Kergon <agk@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This patch ports kcopyd.c to the new, scalable dm_io() interface.
Signed-off-by: NMilan Broz <mbroz@redhat.com>
Signed-off-by: NHeinz Mauelshagen <hjm@redhat.com>
Signed-off-by: NAlasdair G Kergon <agk@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Add a new API to dm-io.c that uses a private mempool and bio_set for each
client.

The new functions to use are dm_io_client_create(), dm_io_client_destroy(),
dm_io_client_resize() and dm_io().
Signed-off-by: NHeinz Mauelshagen <hjm@redhat.com>
Signed-off-by: NAlasdair G Kergon <agk@redhat.com>
Cc: Milan Broz <mbroz@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Introduce struct dm_io_client to prepare for per-client mempools and bio_sets.

Temporary functions bios() and io_pool() choose between the per-client
structures and the global ones so the old and new interfaces can co-exist.

Make error_bits optional.
Signed-off-by: NHeinz Mauelshagen <hjm@redhat.com>
Signed-off-by: NAlasdair G Kergon <agk@redhat.com>
Cc: Milan Broz <mbroz@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Delay decrementing the 'struct io' reference count until after the bio has
been freed so that a bio destructor function may reference it.  Required by a
later patch.
Signed-off-by: NHeinz Mauelshagen <hjm@redhat.com>
Signed-off-by: NAlasdair G Kergon <agk@redhat.com>
Cc: Milan Broz <mbroz@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This patch adds the ability to specify desired features in the mirror
constructor/mapping table.

The first feature of interest is "handle_errors".  Currently, mirroring will
ignore any I/O errors from the devices.  Subsequent patches will check for
this flag and handle the errors.  If flag/feature is not present, mirror will
do nothing - maintaining backwards compatibility.
Signed-off-by: NJonathan E Brassow <jbrassow@redhat.com>
Signed-off-by: NAlasdair G Kergon <agk@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This patch reports the status of the log device so that userspace can detect
the error and take appropriate action.
Signed-off-by: NJonathan E Brassow <jbrassow@redhat.com>
Signed-off-by: NAlasdair G Kergon <agk@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This patch gives the disk logging code the ability to store the fact that an
error occured on the log device.  In addition, an event is raised when an
error is encountered during I/O to the log device.
Signed-off-by: NJonathan E Brassow <jbrassow@redhat.com>
Signed-off-by: NAlasdair G Kergon <agk@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Allow check_device_area to succeed if a device has an i_size of zero.  This
addresses an issue seen on DASD devices setting up a multipath table for paths
in online and offline state.
Signed-off-by: NMike Anderson <andmike@us.ibm.com>
Signed-off-by: NAlasdair G Kergon <agk@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Make the mapped device structure accessible to hardware handlers so error
messages can include the device name.
Signed-off-by: NEdward Goggin <egoggin@emc.com>
Signed-off-by: NAlasdair G Kergon <agk@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Add a new IV generation method 'null' to read old filesystem images created
with SuSE's loop_fish2 module.
Signed-off-by: NLudwig Nussel <ludwig.nussel@suse.de>
Acked-By: NChristophe Saout <christophe@saout.de>
Signed-off-by: NAlasdair G Kergon <agk@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Allocate smaller clones

With the previous dm-crypt fixes, there is no need for the clone bios to have
the same bvec size as the original - we just need to make them big enough for
the remaining number of pages.  The only requirement is that we clear the
"out" index in convert_context, so that crypt_convert starts storing data at
the right position within the clone bio.
Signed-off-by: NOlaf Kirch <olaf.kirch@oracle.com>
Signed-off-by: NAlasdair G Kergon <agk@redhat.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Get rid of first_clone in dm-crypt

This gets rid of first_clone, which is not really needed.  Apparently, cloned
bios used to share their bvec some time way in the past - this is no longer
the case.  Contrarily, this even hurts us if we try to create a clone off
first_clone after it has completed, and crypt_endio has destroyed its bvec.
Signed-off-by: NOlaf Kirch <olaf.kirch@oracle.com>
Signed-off-by: NAlasdair G Kergon <agk@redhat.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Do not access the bio after generic_make_request

We should never access a bio after generic_make_request - there's no guarantee
it still exists.
Signed-off-by: NOlaf Kirch <olaf.kirch@oracle.com>
Signed-off-by: NAlasdair G Kergon <agk@redhat.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Call clone_init early

We need to call clone_init as early as possible - at least before call
bio_put(clone) in any error path.  Otherwise, the destructor will try to
dereference bi_private, which may still be NULL.
Signed-off-by: NOlaf Kirch <olaf.kirch@oracle.com>
Signed-off-by: NAlasdair G Kergon <agk@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Disable barriers in dm-crypt because of current workqueue processing can
reorder requests.

This must be addresed later but for now disabling barriers is needed to
prevent data corruption.
Signed-off-by: NMilan Broz <mbroz@redhat.com>
Signed-off-by: NAlasdair G Kergon <agk@redhat.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This patch replaces the single instance of kmirrord by one instance per mirror
set.  This change is required to avoid a deadlock in kmirrord when the
persistent dirty log of a mirror itself resides on a mirror.  The single
instance of kmirrord then issues a sync write to the dirty log in write_bits
which gets deferred to kmirrord itself later in the call chain.  But kmirrord
never does the deferred work because it is still waiting for the sync
write_bits.

_mirror_sets is removed as it no longer needed, and we always flush the
workqueue before destroying it to ensure all work is complete before
destroying it.
Signed-off-by: NHolger Smolinski <smolinski@de.ibm.com>
Signed-off-by: NAlasdair G Kergon <agk@redhat.com>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This is done in order to be able to run SLUB which expects no modifications
to its page structs.
Signed-off-by: NChristoph Lameter <clameter@sgi.com>
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Fix some of the spelling issues. Fix sentences. Discourage SLOB use
since SLUB can pack objects denser.
Signed-off-by: NChristoph Lameter <clameter@sgi.com>
Cc: Matt Mackall <mpm@selenic.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

No "blank" (or "*") line is allowed between the function name and lines for
it parameter(s).

Cc: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: NPekka Enberg <penberg@cs.helsinki.fi>
Cc: Christoph Lameter <clameter@sgi.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

In some cases SLUB is creating uselessly slabs that are larger than
slub_max_order. Also the layout of some of the slabs was not satisfactory.

Go to an iterarive approach.
Signed-off-by: NChristoph Lameter <clameter@sgi.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

We have information about how long an object existed and about the nodes and
cpus where the allocations and frees took place.  Add that information to the
tracking output in /sys/slab/xx/alloc_calls and /sys/slab/free_calls

This will then enable slabinfo to output nice reports like this:

  christoph@qirst:~/slub$ ./slabinfo kmalloc-128

  Slabcache: kmalloc-128           Aliases:  0 Order :  0

  Sizes (bytes)     Slabs              Debug                Memory
  ------------------------------------------------------------------------
  Object :     128  Total  :      12   Sanity Checks : On   Total:   49152
  SlabObj:     200  Full   :       7   Redzoning     : On   Used :   24832
  SlabSiz:    4096  Partial:       4   Poisoning     : On   Loss :   24320
  Loss   :      72  CpuSlab:       1   Tracking      : On   Lalig:   13968
  Align  :       8  Objects:      20   Tracing       : Off  Lpadd:    1152

  kmalloc-128 has no kmem_cache operations

  kmalloc-128: Kernel object allocation
  -----------------------------------------------------------------------
        6 param_sysfs_setup+0x71/0x130 age=284512/284512/284512 pid=1 nodes=0-1,3
       11 percpu_populate+0x39/0x80 age=283914/284428/284512 pid=1 nodes=0
       21 __register_chrdev_region+0x31/0x170 age=282896/284347/284473 pid=1-1705 nodes=0-2
        1 sys_inotify_init+0x76/0x1c0 age=283423 pid=1004 nodes=0
       19 as_get_io_context+0x32/0xd0 age=6/247567/283988 pid=1-11782 nodes=0,2
       10 ida_pre_get+0x4a/0x80 age=277666/283773/284526 pid=0-2177 nodes=0,2
       24 kobject_kset_add_dir+0x37/0xb0 age=282727/283860/284472 pid=1-1723 nodes=0-2
        1 acpi_ds_build_internal_buffer_obj+0xd3/0x11d age=284508 pid=1 nodes=0
       24 con_insert_unipair+0xd7/0x110 age=284438/284438/284438 pid=1 nodes=0,2
        1 uart_open+0x2d2/0x4b0 age=283896 pid=1 nodes=0
       26 dma_pool_create+0x73/0x1a0 age=282762/282833/282916 pid=1705-1723 nodes=0
        1 neigh_table_init_no_netlink+0xd2/0x210 age=284461 pid=1 nodes=0
        2 neigh_parms_alloc+0x2b/0xe0 age=284410/284411/284412 pid=1 nodes=2
        2 neigh_resolve_output+0x1e1/0x280 age=276289/276291/276293 pid=0-2443 nodes=0
        1 netlink_kernel_create+0x90/0x170 age=284472 pid=1 nodes=0
        4 xt_alloc_table_info+0x39/0xf0 age=283958/283958/283959 pid=1 nodes=1
        3 fn_hash_insert+0x473/0x720 age=277653/277661/277666 pid=2177-2185 nodes=0
        1 get_mtrr_state+0x285/0x2a0 age=284526 pid=0 nodes=0
        1 cacheinfo_cpu_callback+0x26d/0x3e0 age=284458 pid=1 nodes=0
       29 kernel_param_sysfs_setup+0x25/0x90 age=284511/284511/284512 pid=1 nodes=0-1,3
        5 process_zones+0x5e/0x170 age=284546/284546/284546 pid=0 nodes=0
        1 drm_core_init+0x48/0x160 age=284421 pid=1 nodes=2

  kmalloc-128: Kernel object freeing
  ------------------------------------------------------------------------
      163 <not-available> age=4295176847 pid=0 nodes=0-3
        1 __vunmap+0x6e/0xf0 age=282907 pid=1723 nodes=0
       28 free_as_io_context+0x12/0x90 age=9243/262197/283474 pid=42-11754 nodes=0
        1 acpi_get_object_info+0x1b7/0x1d4 age=284475 pid=1 nodes=0
        1 do_acpi_find_child+0x45/0x4e age=284475 pid=1 nodes=0

  NUMA nodes           :    0    1    2    3
  ------------------------------------------
  All slabs                 7    2    2    1
  Partial slabs             2    2    0    0
Signed-off-by: NChristoph Lameter <clameter@sgi.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

CONFIG_SLUB_DEBUG can be used to switch off the debugging and sysfs components
of SLUB.  Thus SLUB will be able to replace SLOB.  SLUB can arrange objects in
a denser way than SLOB and the code size should be minimal without debugging
and sysfs support.

Note that CONFIG_SLUB_DEBUG is materially different from CONFIG_SLAB_DEBUG.
CONFIG_SLAB_DEBUG is used to enable slab debugging in SLAB.  SLUB enables
debugging via a boot parameter.  SLUB debug code should always be present.

CONFIG_SLUB_DEBUG can be modified in the embedded config section.
Signed-off-by: NChristoph Lameter <clameter@sgi.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Move the tracking definitions and the check_valid_pointer() function away from
the debugging related functions.
Signed-off-by: NChristoph Lameter <clameter@sgi.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Trace in both slab_alloc and slab_free has a lot of common code.  Use a single
function for both.
Signed-off-by: NChristoph Lameter <clameter@sgi.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This replaces the PageError() checking.  DebugSlab is clearer and allows for
future changes to the page bit used.  We also need it to support
CONFIG_SLUB_DEBUG.
Signed-off-by: NChristoph Lameter <clameter@sgi.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Move the resiliency check into the SYSFS section after validate_slab that is
used by the resiliency check.  This will avoid a forward declaration.
Signed-off-by: NChristoph Lameter <clameter@sgi.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Scanning of objects happens in a number of functions.  Consolidate that code.
DECLARE_BITMAP instead of coding the declaration for bitmaps.
Signed-off-by: NChristoph Lameter <clameter@sgi.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Update comments throughout SLUB to reflect the new developments.  Fix up
various awkward sentences.
Signed-off-by: NChristoph Lameter <clameter@sgi.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Its only purpose was to bring some sort of symmetry to sysfs usage when
dealing with bootstrapping per cpu flushing.  Since we do not time out slabs
anymore we have no need to run finish_bootstrap even without sysfs.  Fold it
back into slab_sysfs_init and drop the initcall for the !SYFS case.
Signed-off-by: NChristoph Lameter <clameter@sgi.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

We really do not need all this gaga there.

ksize gives us all the information we need to figure out if the object can
cope with the new size.
Signed-off-by: NChristoph Lameter <clameter@sgi.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

We needlessly duplicate code. Also make check_valid_pointer inline.
Signed-off-by: NChristoph LAemter <clameter@sgi.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

-e Show empty slabs
-d Modification of slab debug options at runtime
-o Operations. Display of ctor / dtor etc.
-r Report: Display all available information about a slabcache.

Cleanup tracking display and make it work right.
Signed-off-by: NChristoph Lameter <clameter@sgi.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>