kernel/linux.git/drivers/md/raid5.c, branch v2.6.28

md: Relax minimum size restrictions on chunk_size.

2008-10-13T00:55:12+00:00

Currently, the 'chunk_size' of an array must be at-least PAGE_SIZE. This makes moving an array to a machine with a larger PAGE_SIZE, or changing the kernel to use a larger PAGE_SIZE, can stop an array from working. For RAID10 and RAID4/5/6, this is non-trivial to fix as the resync process works on whole pages at a time, and assumes them to be wholly within a stripe. For other raid personalities, this restriction is not needed at all and can be dropped. So remove the test on chunk_size from common can, and add it in just the places where it is needed: raid10 and raid4/5/6. Signed-off-by: NeilBrown

md: remove space after function name in declaration and call.

2008-10-13T00:55:12+00:00

Having function (args) instead of function(args) make is harder to search for calls of particular functions. So remove all those spaces. Signed-off-by: NeilBrown

md: Remove unnecessary #includes, #defines, and function declarations.

2008-10-13T00:55:12+00:00

A lot of cruft has gathered over the years. Time to remove it. Signed-off-by: NeilBrown

block: move stats from disk to part0

2008-10-09T06:56:08+00:00

Move stats related fields - stamp, in_flight, dkstats - from disk to part0 and unify stat handling such that... * part_stat_*() now updates part0 together if the specified partition is not part0. ie. part_stat_*() are now essentially all_stat_*(). * {disk|all}_stat_*() are gone. * part_round_stats() is updated similary. It handles part0 stats automatically and disk_round_stats() is killed. * part_{inc|dec}_in_fligh() is implemented which automatically updates part0 stats for parts other than part0. * disk_map_sector_rcu() is updated to return part0 if no part matches. Combined with the above changes, this makes NULL special case handling in callers unnecessary. * Separate stats show code paths for disk are collapsed into part stats show code paths. * Rename disk_stat_lock/unlock() to part_stat_lock/unlock() While at it, reposition stat handling macros a bit and add missing parentheses around macro parameters. Signed-off-by: Tejun Heo Signed-off-by: Jens Axboe

block: fix diskstats access

2008-10-09T06:56:06+00:00

There are two variants of stat functions - ones prefixed with double underbars which don't care about preemption and ones without which disable preemption before manipulating per-cpu counters. It's unclear whether the underbarred ones assume that preemtion is disabled on entry as some callers don't do that. This patch unifies diskstats access by implementing disk_stat_lock() and disk_stat_unlock() which take care of both RCU (for partition access) and preemption (for per-cpu counter access). diskstats access should always be enclosed between the two functions. As such, there's no need for the versions which disables preemption. They're removed and double underbars ones are renamed to drop the underbars. As an extra argument is added, there's no danger of using the old version unconverted. disk_stat_lock() uses get_cpu() and returns the cpu index and all diskstat functions which access per-cpu counters now has @cpu argument to help RT. This change adds RCU or preemption operations at some places but also collapses several preemption ops into one at others. Overall, the performance difference should be negligible as all involved ops are very lightweight per-cpu ones. Signed-off-by: Tejun Heo Cc: Peter Zijlstra Signed-off-by: Jens Axboe

block: make bi_phys_segments an unsigned int instead of short

2008-10-09T06:56:03+00:00

raid5 can overflow with more than 255 stripes, and we can increase it to an int for free on both 32 and 64-bit archs due to the padding. Signed-off-by: Jens Axboe

block: raid fixups for removal of bi_hw_segments

2008-10-09T06:56:03+00:00

Signed-off-by: Jens Axboe

Don't let a blocked_rdev interfere with read request in raid5/6

2008-08-05T05:56:32+00:00

When we have externally managed metadata, we need to mark a failed device as 'Blocked' and not allow any writes until that device have been marked as faulty in the metadata and the Blocked flag has been removed. However it is perfectly OK to allow read requests when there is a Blocked device, and with a readonly array, there may not be any metadata-handler watching for blocked devices. So in raid5/raid6 only allow a Blocked device to interfere with Write request or resync. Read requests go through untouched. raid1 and raid10 already differentiate between read and write properly. Signed-off-by: NeilBrown

Fail safely when trying to grow an array with a write-intent bitmap.

2008-08-05T05:56:32+00:00

We cannot currently change the size of a write-intent bitmap. So if we change the size of an array which has such a bitmap, it tries to set bits beyond the end of the bitmap. For now, simply reject any request to change the size of an array which has a bitmap. mdadm can remove the bitmap and add a new one after the array has changed size. Signed-off-by: NeilBrown

Merge branch 'for-linus' of git://neil.brown.name/md

2008-08-01T18:56:07+00:00

* 'for-linus' of git://neil.brown.name/md: md: raid10: wake up frozen array md: do not count blocked devices as spares md: do not progress the resync process if the stripe was blocked md: delay notification of 'active_idle' to the recovery thread md: fix merge error md: move async_tx_issue_pending_all outside spin_lock_irq