linux-toradex.git/drivers/md/dm-crypt.c, branch v3.11

block: Convert some code to bio_for_each_segment_all()

2013-03-23T21:26:30+00:00

More prep work for immutable bvecs:

A few places in the code were either open coding or using the wrong
version - fix.

After we introduce the bvec iter, it'll no longer be possible to modify
the biovec through bio_for_each_segment_all() - it doesn't increment a
pointer to the current bvec, you pass in a struct bio_vec (not a
pointer) which is updated with what the current biovec would be (taking
into account bi_bvec_done and bi_size).

So because of that it's more worthwhile to be consistent about
bio_for_each_segment()/bio_for_each_segment_all() usage.

Signed-off-by: Kent Overstreet 
CC: Jens Axboe 
CC: NeilBrown 
CC: Alasdair Kergon 
CC: dm-devel@redhat.com
CC: Alexander Viro

dm: rename request variables to bios

2013-03-01T22:45:47+00:00

Use 'bio' in the name of variables and functions that deal with
bios rather than 'request' to avoid confusion with the normal
block layer use of 'request'.

No functional changes.

Signed-off-by: Alasdair G Kergon

dm: fix truncated status strings

2013-03-01T22:45:44+00:00

Avoid returning a truncated table or status string instead of setting
the DM_BUFFER_FULL_FLAG when the last target of a table fills the
buffer.

When processing a table or status request, the function retrieve_status
calls ti->type->status. If ti->type->status returns non-zero,
retrieve_status assumes that the buffer overflowed and sets
DM_BUFFER_FULL_FLAG.

However, targets don't return non-zero values from their status method
on overflow. Most targets returns always zero.

If a buffer overflow happens in a target that is not the last in the
table, it gets noticed during the next iteration of the loop in
retrieve_status; but if a buffer overflow happens in the last target, it
goes unnoticed and erroneously truncated data is returned.

In the current code, the targets behave in the following way:
* dm-crypt returns -ENOMEM if there is not enough space to store the
  key, but it returns 0 on all other overflows.
* dm-thin returns errors from the status method if a disk error happened.
  This is incorrect because retrieve_status doesn't check the error
  code, it assumes that all non-zero values mean buffer overflow.
* all the other targets always return 0.

This patch changes the ti->type->status function to return void (because
most targets don't use the return code). Overflow is detected in
retrieve_status: if the status method fills up the remaining space
completely, it is assumed that buffer overflow happened.

Cc: stable@vger.kernel.org
Signed-off-by: Mikulas Patocka 
Signed-off-by: Alasdair G Kergon

dm: remove map_info

2012-12-21T20:23:41+00:00

This patch removes map_info from bio-based device mapper targets.
map_info is still used for request-based targets.

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

block: Add bio_clone_bioset(), bio_clone_kmalloc()

2012-09-09T08:35:39+00:00

Previously, there was bio_clone() but it only allocated from the fs bio
set; as a result various users were open coding it and using
__bio_clone().

This changes bio_clone() to become bio_clone_bioset(), and then we add
bio_clone() and bio_clone_kmalloc() as wrappers around it, making use of
the functionality the last patch adedd.

This will also help in a later patch changing how bio cloning works.

Signed-off-by: Kent Overstreet 
CC: Jens Axboe 
CC: NeilBrown 
CC: Alasdair Kergon 
CC: Boaz Harrosh 
CC: Jeff Garzik 
Acked-by: Jeff Garzik 
Signed-off-by: Jens Axboe

block: Generalized bio pool freeing

2012-09-09T08:35:38+00:00

With the old code, when you allocate a bio from a bio pool you have to
implement your own destructor that knows how to find the bio pool the
bio was originally allocated from.

This adds a new field to struct bio (bi_pool) and changes
bio_alloc_bioset() to use it. This makes various bio destructors
unnecessary, so they're then deleted.

v6: Explain the temporary if statement in bio_put

Signed-off-by: Kent Overstreet 
CC: Jens Axboe 
CC: NeilBrown 
CC: Alasdair Kergon 
CC: Nicholas Bellinger 
CC: Lars Ellenberg 
Acked-by: Tejun Heo 
Acked-by: Nicholas Bellinger 
Signed-off-by: Jens Axboe

dm thin: commit before gathering status

2012-07-27T14:08:16+00:00

Commit outstanding metadata before returning the status for a dm thin
pool so that the numbers reported are as up-to-date as possible.

The commit is not performed if the device is suspended or if
the DM_NOFLUSH_FLAG is supplied by userspace and passed to the target
through a new 'status_flags' parameter in the target's dm_status_fn.

The userspace dmsetup tool will support the --noflush flag with the
'dmsetup status' and 'dmsetup wait' commands from version 1.02.76
onwards.

Tested-by: Mike Snitzer 
Signed-off-by: Alasdair G Kergon

dm: use bool bitfields in struct dm_target

2012-07-27T14:08:08+00:00

Use boolean bit fields for flags in struct dm_target.

Signed-off-by: Alasdair G Kergon

dm crypt: rename struct convert_context sector field

2012-07-27T14:08:05+00:00

Rename sector to cc_sector in dm-crypt's convert_context struct.

This is preparation for a future patch that merges dm_io and
convert_context which both have a "sector" field.

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

dm crypt: store crypt_config instead of dm_target struct

2012-07-27T14:08:05+00:00

Store the crypt_config struct pointer directly in struct dm_crypt_io
instead of the dm_target struct pointer.

Target information is never used - only target->private is referenced,
thus we can change it to point directly to struct crypt_config.

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