kernel.git/drivers/md/raid1.c, branch linux-2.6.34.y

md/raid1: really fix recovery looping when single good device fails.

2011-04-17T20:15:43Z

commit 8f9e0ee38f75d4740daa9e42c8af628d33d19a02 upstream. Commit 4044ba58dd15cb01797c4fd034f39ef4a75f7cc3 supposedly fixed a problem where if a raid1 with just one good device gets a read-error during recovery, the recovery would abort and immediately restart in an infinite loop. However it depended on raid1_remove_disk removing the spare device from the array. But that does not happen in this case. So add a test so that in the 'recovery_disabled' case, the device will be removed. This suitable for any kernel since 2.6.29 which is when recovery_disabled was introduced. Reported-by: Sebastian Färber Signed-off-by: NeilBrown Signed-off-by: Paul Gortmaker

md/raid1: delay reads that could overtake behind-writes.

2010-08-13T20:27:37Z

commit e555190d82c0f58e825e3cbd9e6ebe2e7ac713bd upstream. When a raid1 array is configured to support write-behind on some devices, it normally only reads from other devices. If all devices are write-behind (because the rest have failed) it is possible for a read request to be serviced before a behind-write request, which would appear as data corruption. So when forced to read from a WriteMostly device, wait for any write-behind to complete, and don't start any more behind-writes. Signed-off-by: NeilBrown Signed-off-by: Greg Kroah-Hartman

md: Fix read balancing in RAID1 and RAID10 on drives > 2TB

2010-07-05T18:22:22Z

commit af3a2cd6b8a479345786e7fe5e199ad2f6240e56 upstream. read_balance uses a "unsigned long" for a sector number which will get truncated beyond 2TB. This will cause read-balancing to be non-optimal, and can cause data to be read from the 'wrong' branch during a resync. This has a very small chance of returning wrong data. Reported-by: Jordan Russell Signed-off-by: NeilBrown Signed-off-by: Greg Kroah-Hartman

md/raid1: fix counting of write targets.

2010-07-05T18:22:21Z

commit 964147d5c86d63be79b442c30f3783d49860c078 upstream. There is a very small race window when writing to a RAID1 such that if a device is marked faulty at exactly the wrong time, the write-in-progress will not be sent to the device, but the bitmap (if present) will be updated to say that the write was sent. Then if the device turned out to still be usable as was re-added to the array, the bitmap-based-resync would skip resyncing that block, possibly leading to corruption. This would only be a problem if no further writes were issued to that area of the device (i.e. that bitmap chunk). Suitable for any pending -stable kernel. Signed-off-by: NeilBrown Signed-off-by: Greg Kroah-Hartman

include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h

2010-03-30T13:02:32Z

percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo Guess-its-ok-by: Christoph Lameter Cc: Ingo Molnar Cc: Lee Schermerhorn

md: deal with merge_bvec_fn in component devices better.

2010-03-16T06:04:24Z

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_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 Cc: stable@kernel.org

block: Rename blk_queue_max_sectors to blk_queue_max_hw_sectors

2010-02-26T12:58:08Z

The block layer calling convention is blk_queue_. blk_queue_max_sectors predates this practice, leading to some confusion. Rename the function to appropriately reflect that its intended use is to set max_hw_sectors. Also introduce a temporary wrapper for backwards compability. This can be removed after the merge window is closed. Signed-off-by: Martin K. Petersen Signed-off-by: Jens Axboe

md: add MODULE_DESCRIPTION for all md related modules.

2009-12-14T01:51:41Z

Suggested by Oren Held Signed-off-by: NeilBrown

md: move offset, daemon_sleep and chunksize out of bitmap structure

2009-12-14T01:51:41Z

... and into bitmap_info. These are all configuration parameters that need to be set before the bitmap is created. Signed-off-by: NeilBrown

md/raid1: add takeover support for raid5->raid1

2009-12-14T01:51:41Z

A 2-device raid5 array can now be converted to raid1. Signed-off-by: NeilBrown