linux-toradex.git/drivers/md/dm-ioctl.c, branch v2.6.30-rc5

dm: add integrity support

2009-04-08T23:27:12+00:00

This patch provides support for data integrity passthrough in the device
mapper.

 - If one or more component devices support integrity an integrity
   profile is preallocated for the DM device.

 - If all component devices have compatible profiles the DM device is
   flagged as capable.

 - Handle integrity metadata when splitting and cloning bios.

Signed-off-by: Martin K. Petersen 
Signed-off-by: Alasdair G Kergon

dm table: rework reference counting fix

2009-03-16T17:44:26+00:00

Fix an error introduced in dm-table-rework-reference-counting.patch.

When there is failure after table initialization, we need to use
dm_table_destroy, not dm_table_put, to free the table.

dm_table_put may be used only after dm_table_get.

Cc: Kiyoshi Ueda 
Signed-off-by: Mikulas Patocka 
Reviewed-by: Jonathan Brassow 
Reviewed-by: Alasdair G Kergon 
Signed-off-by: Alasdair G Kergon

dm ioctl: validate name length when renaming

2009-03-16T16:56:01+00:00

When renaming a mapped device validate the length of the new name.

The rename ioctl accepted any correctly-terminated string enclosed
within the data passed from userspace.  The other ioctls enforce a
size limit of DM_NAME_LEN.  If the name is changed and becomes longer
than that, the device can no longer be addressed by name.

Fix it by properly checking for device name length (including
terminating zero).

Cc: stable@kernel.org
Signed-off-by: Milan Broz 
Reviewed-by: Jonathan Brassow 
Reviewed-by: Alasdair G Kergon 
Signed-off-by: Alasdair G Kergon

dm table: rework reference counting

2009-01-06T03:05:10+00:00

Rework table reference counting.

The existing code uses a reference counter. When the last reference is
dropped and the counter reaches zero, the table destructor is called.
Table reference counters are acquired/released from upcalls from other
kernel code (dm_any_congested, dm_merge_bvec, dm_unplug_all).
If the reference counter reaches zero in one of the upcalls, the table
destructor is called from almost random kernel code.

This leads to various problems:
* dm_any_congested being called under a spinlock, which calls the
  destructor, which calls some sleeping function.
* the destructor attempting to take a lock that is already taken by the
  same process.
* stale reference from some other kernel code keeps the table
  constructed, which keeps some devices open, even after successful
  return from "dmsetup remove". This can confuse lvm and prevent closing
  of underlying devices or reusing device minor numbers.

The patch changes reference counting so that the table destructor can be
called only at predetermined places.

The table has always exactly one reference from either mapped_device->map
or hash_cell->new_map. After this patch, this reference is not counted
in table->holders.  A pair of dm_create_table/dm_destroy_table functions
is used for table creation/destruction.

Temporary references from the other code increase table->holders. A pair
of dm_table_get/dm_table_put functions is used to manipulate it.

When the table is about to be destroyed, we wait for table->holders to
reach 0. Then, we call the table destructor.  We use active waiting with
msleep(1), because the situation happens rarely (to one user in 5 years)
and removing the device isn't performance-critical task: the user doesn't
care if it takes one tick more or not.

This way, the destructor is called only at specific points
(dm_table_destroy function) and the above problems associated with lazy
destruction can't happen.

Finally remove the temporary protection added to dm_any_congested().

Signed-off-by: Mikulas Patocka 
Signed-off-by: Alasdair G Kergon

dm ioctl: allow dm_copy_name_and_uuid to return only one field

2009-01-06T03:05:04+00:00

Allow NULL buffer in dm_copy_name_and_uuid if you only want to return one of
the fields.

(Required by a following patch that adds these fields to sysfs.)

Signed-off-by: Milan Broz 
Reviewed-by: Alasdair G Kergon 
Signed-off-by: Alasdair G Kergon

[PATCH] introduce fmode_t, do annotations

2008-10-21T11:47:06+00:00

Signed-off-by: Al Viro

Merge git://git.kernel.org/pub/scm/linux/kernel/git/agk/linux-2.6-dm

2008-10-10T18:11:47+00:00

* git://git.kernel.org/pub/scm/linux/kernel/git/agk/linux-2.6-dm:
  dm: detect lost queue
  dm: publish dm_vcalloc
  dm: publish dm_table_unplug_all
  dm: publish dm_get_mapinfo
  dm: export struct dm_dev
  dm crypt: avoid unnecessary wait when splitting bio
  dm crypt: tidy ctx pending
  dm crypt: fix async inc_pending
  dm crypt: move dec_pending on error into write_io_submit
  dm crypt: remove inc_pending from write_io_submit
  dm crypt: tidy write loop pending
  dm crypt: tidy crypt alloc
  dm crypt: tidy inc pending
  dm exception store: use chunk_t for_areas
  dm exception store: introduce area_location function
  dm raid1: kcopyd should stop on error if errors handled
  dm mpath: remove is_active from struct dm_path
  dm mpath: use more error codes

Fixed up trivial conflict in drivers/md/dm-mpath.c manually.

dm: export struct dm_dev

2008-10-10T12:37:09+00:00

Split struct dm_dev in two and publish the part that other targets need in
include/linux/device-mapper.h.

Signed-off-by: Mikulas Patocka 
Signed-off-by: Alasdair G Kergon

block: move policy from disk to part0

2008-10-09T06:56:07+00:00

Move disk->policy to part0->policy.  Implement and use get_disk_ro().

Signed-off-by: Tejun Heo 
Signed-off-by: Jens Axboe

block: don't depend on consecutive minor space

2008-10-09T06:56:05+00:00

* Implement disk_devt() and part_devt() and use them to directly
  access devt instead of computing it from ->major and ->first_minor.

  Note that all references to ->major and ->first_minor outside of
  block layer is used to determine devt of the disk (the part0) and as
  ->major and ->first_minor will continue to represent devt for the
  disk, converting these users aren't strictly necessary.  However,
  convert them for consistency.

* Implement disk_max_parts() to avoid directly deferencing
  genhd->minors.

* Update bdget_disk() such that it doesn't assume consecutive minor
  space.

* Move devt computation from register_disk() to add_disk() and make it
  the only one (all other usages use the initially determined value).

These changes clean up the code and will help disk->part dereference
fix and extended block device numbers.

Signed-off-by: Tejun Heo 
Signed-off-by: Jens Axboe