linux-toradex.git/drivers/md/raid0.c, branch v2.6.32.35

md: deal with merge_bvec_fn in component devices better.

2010-04-26T14:41:35+00:00

commit 627a2d3c29427637f4c5d31ccc7fcbd8d312cd71 upstream.

If a component device has a merge_bvec_fn then as we never call it
we must ensure we never need to.  Currently this is done by setting
max_sector to 1 PAGE, however this does not stop a bio being created
with several sub-page iovecs that would violate the merge_bvec_fn.

So instead set max_phys_segments to 1 and set the segment boundary to the
same as a page boundary to ensure there is only ever one single-page
segment of IO requested at a time.

This can particularly be an issue when 'xen' is used as it is
known to submit multiple small buffers in a single bio.

Signed-off-by: NeilBrown 
Signed-off-by: Greg Kroah-Hartman

md: report device as congested when suspended

2009-09-23T08:10:29+00:00

This should writeback from coming when the device is temporarily
suspended.

Signed-off-by: NeilBrown

md: remove sparse waring "symbol xxx shadows an earlier one"

2009-09-23T08:06:41+00:00

Rename some variable and remove some duplicate definitions
to avoid there warnings.  None of them are actual errors.

Signed-off-by: NeilBrown

bio: first step in sanitizing the bio->bi_rw flag testing

2009-09-11T12:33:31+00:00

Get rid of any functions that test for these bits and make callers
use bio_rw_flagged() directly. Then it is at least directly apparent
what variable and flag they check.

Signed-off-by: Jens Axboe

md: Push down data integrity code to personalities.

2009-08-03T00:59:47+00:00

This patch replaces md_integrity_check() by two new public functions:
md_integrity_register() and md_integrity_add_rdev() which are both
personality-independent.

md_integrity_register() is called from the ->run and ->hot_remove
methods of all personalities that support data integrity.  The
function iterates over the component devices of the array and
determines if all active devices are integrity capable and if their
profiles match. If this is the case, the common profile is registered
for the mddev via blk_integrity_register().

The second new function, md_integrity_add_rdev() is called from the
->hot_add_disk methods, i.e. whenever a new device is being added
to a raid array. If the new device does not support data integrity,
or has a profile different from the one already registered, data
integrity for the mddev is disabled.

For raid0 and linear, only the call to md_integrity_register() from
the ->run method is necessary.

Signed-off-by: Andre Noll 
Signed-off-by: NeilBrown

md: Use new topology calls to indicate alignment and I/O sizes

2009-07-01T01:13:45+00:00

Switch MD over to the new disk_stack_limits() function which checks for
aligment and adjusts preferred I/O sizes when stacking.

Also indicate preferred I/O sizes where applicable.

Signed-off-by: Martin K. Petersen 
Signed-off-by: Mike Snitzer 
Signed-off-by: NeilBrown

md: Move check for bitmap presence to personality code.

2009-06-17T22:49:23+00:00

If the superblock of a component device indicates the presence of a
bitmap but the corresponding raid personality does not support bitmaps
(raid0, linear, multipath, faulty), then something is seriously wrong
and we'd better refuse to run such an array.

Currently, this check is performed while the superblocks are examined,
i.e. before entering personality code. Therefore the generic md layer
must know which raid levels support bitmaps and which do not.

This patch avoids this layer violation without adding identical code
to various personalities. This is accomplished by introducing a new
public function to md.c, md_check_no_bitmap(), which replaces the
hard-coded checks in the superblock loading functions.

A call to md_check_no_bitmap() is added to the ->run method of each
personality which does not support bitmaps and assembly is aborted
if at least one component device contains a bitmap.

Signed-off-by: Andre Noll 
Signed-off-by: NeilBrown

md: raid0/linear: ensure device sizes are rounded to chunk size.

2009-06-17T22:48:55+00:00

This is currently ensured by common code, but it is more reliable to
ensure it where it is needed in personality code.
All the other personalities that care already round the size to
the chunk_size.  raid0 and linear are the only hold-outs.

Signed-off-by: NeilBrown

md: raid0: chunk_sectors cleanups.

2009-06-17T22:47:00+00:00

following the conversion to chunk_sectors, there is room
for cleaning up a little.

Signed-off-by: NeilBrown

md: Make mddev->chunk_size sector-based.

2009-06-17T22:45:01+00:00

This patch renames the chunk_size field to chunk_sectors with the
implied change of semantics.  Since

	is_power_of_2(chunk_size) = is_power_of_2(chunk_sectors << 9)
				  = is_power_of_2(chunk_sectors)

these bits don't need an adjustment for the shift.

Signed-off-by: Andre Noll 
Signed-off-by: NeilBrown