kernel/linux.git/drivers/md/md.c, branch linux-2.6.22.y

md: fix bug with linear hot-add and elsewhere

2007-05-24T03:14:14+00:00

Adding a drive to a linear array seems to have stopped working, due to changes elsewhere in md, and insufficient ongoing testing... So the patch to make linear hot-add work in the first place introduced a subtle bug elsewhere that interracts poorly with older version of mdadm. This fixes it all up. Signed-off-by: Neil Brown Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

md: improve the is_mddev_idle test

2007-05-11T15:29:37+00:00

During a 'resync' or similar activity, md checks if the devices in the array are otherwise active and winds back resync activity when they are. This test in done in is_mddev_idle, and it is somewhat fragile - it sometimes thinks there is non-sync io when there isn't. The test compares the total sectors of io (disk_stat_read) with the sectors of resync io (disk->sync_io). This has problems because total sectors gets updated when a request completes, while resync io gets updated when the request is submitted. The time difference can cause large differenced between the two which do not actually imply non-resync activity. The test currently allows for some fuzz (+/- 4096) but there are some cases when it is not enough. The test currently looks for any (non-fuzz) difference, either positive or negative. This clearly is not needed. Any non-sync activity will cause the total sectors to grow faster than the sync_io count (never slower) so we only need to look for a positive differences. If we do this then the amount of in-flight sync io will never cause the appearance of non-sync IO. Once enough non-sync IO to worry about starts happening, resync will be slowed down and the measurements will thus be more precise (as there is less in-flight) and control of resync will still be suitably responsive. Signed-off-by: Neil Brown Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

Revert "md: improve partition detection in md array"

2007-05-10T01:51:36+00:00

This reverts commit 5b479c91da90eef605f851508744bfe8269591a0. Quoth Neil Brown: "It causes an oops when auto-detecting raid arrays, and it doesn't seem easy to fix. The array may not be 'open' when do_md_run is called, so bdev->bd_disk might be NULL, so bd_set_size can oops. This whole approach of opening an md device before it has been assembled just seems to get more and more painful. I think I'm going to have to come up with something clever to provide both backward comparability with usage expectation, and sane integration into the rest of the kernel." Signed-off-by: Linus Torvalds

md: improve partition detection in md array

2007-05-09T19:30:57+00:00

md currently uses ->media_changed to make sure rescan_partitions is call on md array after they are assembled. However that doesn't happen until the array is opened, which is later than some people would like. So use blkdev_ioctl to do the rescan immediately that the array has been assembled. This means we can remove all the ->change infrastructure as it was only used to trigger a partition rescan. Signed-off-by: Neil Brown Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

md: allow reshape_position for md arrays to be set via sysfs

2007-05-09T19:30:57+00:00

"reshape_position" records how much progress has been made on a "reshape" (adding drives, changing layout or chunksize). When it is set, the number of drives, layout and chunksize can have two possible values, an old an a new. So allow these different values to be visible, and allow both old and new to be set: Set the old ones first, then the reshape_position, then the new values. Signed-off-by: Neil Brown Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

md: stop using csum_partial for checksum calculation in md

2007-05-09T19:30:57+00:00

If CONFIG_NET is not selected, csum_partial is not exported, so md.ko cannot use it. We shouldn't really be using csum_partial anyway as it is an internal-to-networking interface. So replace it with C code to do the same thing. Speed is not crucial here, so something simple and correct is best. Signed-off-by: Neil Brown Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

md: move test for whether level supports bitmap to correct place

2007-05-09T19:30:57+00:00

We need to check for internal-consistency of superblock in load_super. validate_super is for inter-device consistency. With the test in the wrong place, a badly created array will confuse md rather an produce sensible errors. Signed-off-by: Neil Brown Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

md: cleanup: use seq_release_private() where appropriate

2007-05-09T19:30:57+00:00

We can save some lines of code by using seq_release_private(). Signed-off-by: Martin Peschke Acked-by: Neil Brown Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

drivers/md.c: Use ARRAY_SIZE macro when appropriate

2007-05-09T19:30:57+00:00

Use ARRAY_SIZE macro already defined in kernel.h Signed-off-by: Ahmed S. Darwish Acked-by: Neil Brown Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

mm: remove destroy_dirty_buffers from invalidate_bdev()

2007-05-07T19:12:55+00:00

Remove the destroy_dirty_buffers argument from invalidate_bdev(), it hasn't been used in 6 years (so akpm says). find * -name \*.[ch] | xargs grep -l invalidate_bdev | while read file; do quilt add $file; sed -ie 's/invalidate_bdev($[^,]*$,[^)]*)/invalidate_bdev(\1)/g' $file; done Signed-off-by: Peter Zijlstra Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds