diff options
| author | Jonathan Brassow <jbrassow@redhat.com> | 2011-01-14 09:14:34 +1100 |
|---|---|---|
| committer | NeilBrown <neilb@suse.de> | 2011-01-14 09:14:34 +1100 |
| commit | a6ff7e089c7fca813c956ccbed824087e89a3a49 (patch) | |
| tree | 6537f72a2431c30601736676e9b1f89a7f1fe52e | |
| parent | ccebd4c4159462c96397ae9af9c667bb394d7b70 (diff) | |
| download | linux-3.10-a6ff7e089c7fca813c956ccbed824087e89a3a49.tar.gz linux-3.10-a6ff7e089c7fca813c956ccbed824087e89a3a49.tar.bz2 linux-3.10-a6ff7e089c7fca813c956ccbed824087e89a3a49.zip | |
md: separate meta and data devs
Allow the metadata to be on a separate device from the
data.
This doesn't mean the data and metadata will by on separate
physical devices - it simply gives device-mapper and userspace
tools more flexibility.
Signed-off-by: NeilBrown <neilb@suse.de>
| -rw-r--r-- | drivers/md/bitmap.c | 6 | ||||
| -rw-r--r-- | drivers/md/md.c | 10 | ||||
| -rw-r--r-- | drivers/md/md.h | 6 |
3 files changed, 17 insertions, 5 deletions
diff --git a/drivers/md/bitmap.c b/drivers/md/bitmap.c index 1977765ff96..6cf587196b9 100644 --- a/drivers/md/bitmap.c +++ b/drivers/md/bitmap.c @@ -264,14 +264,18 @@ static mdk_rdev_t *next_active_rdev(mdk_rdev_t *rdev, mddev_t *mddev) static int write_sb_page(struct bitmap *bitmap, struct page *page, int wait) { mdk_rdev_t *rdev = NULL; + struct block_device *bdev; mddev_t *mddev = bitmap->mddev; while ((rdev = next_active_rdev(rdev, mddev)) != NULL) { int size = PAGE_SIZE; loff_t offset = mddev->bitmap_info.offset; + + bdev = (rdev->meta_bdev) ? rdev->meta_bdev : rdev->bdev; + if (page->index == bitmap->file_pages-1) size = roundup(bitmap->last_page_size, - bdev_logical_block_size(rdev->bdev)); + bdev_logical_block_size(bdev)); /* Just make sure we aren't corrupting data or * metadata */ diff --git a/drivers/md/md.c b/drivers/md/md.c index 0bc10cc4b96..b98a85fd10b 100644 --- a/drivers/md/md.c +++ b/drivers/md/md.c @@ -765,7 +765,7 @@ void md_super_write(mddev_t *mddev, mdk_rdev_t *rdev, */ struct bio *bio = bio_alloc_mddev(GFP_NOIO, 1, mddev); - bio->bi_bdev = rdev->bdev; + bio->bi_bdev = rdev->meta_bdev ? rdev->meta_bdev : rdev->bdev; bio->bi_sector = sector; bio_add_page(bio, page, size, 0); bio->bi_private = rdev; @@ -803,7 +803,8 @@ int sync_page_io(mdk_rdev_t *rdev, sector_t sector, int size, rw |= REQ_SYNC | REQ_UNPLUG; - bio->bi_bdev = rdev->bdev; + bio->bi_bdev = (metadata_op && rdev->meta_bdev) ? + rdev->meta_bdev : rdev->bdev; if (metadata_op) bio->bi_sector = sector + rdev->sb_start; else @@ -4435,7 +4436,9 @@ int md_run(mddev_t *mddev) * We don't want the data to overlap the metadata, * Internal Bitmap issues have been handled elsewhere. */ - if (rdev->data_offset < rdev->sb_start) { + if (rdev->meta_bdev) { + /* Nothing to check */; + } else if (rdev->data_offset < rdev->sb_start) { if (mddev->dev_sectors && rdev->data_offset + mddev->dev_sectors > rdev->sb_start) { @@ -5532,7 +5535,6 @@ static int update_size(mddev_t *mddev, sector_t num_sectors) * sb_start or, if that is <data_offset, it must fit before the size * of each device. If num_sectors is zero, we find the largest size * that fits. - */ if (mddev->sync_thread) return -EBUSY; diff --git a/drivers/md/md.h b/drivers/md/md.h index 7e4f358a26a..eec517ced31 100644 --- a/drivers/md/md.h +++ b/drivers/md/md.h @@ -60,6 +60,12 @@ struct mdk_rdev_s mddev_t *mddev; /* RAID array if running */ int last_events; /* IO event timestamp */ + /* + * If meta_bdev is non-NULL, it means that a separate device is + * being used to store the metadata (superblock/bitmap) which + * would otherwise be contained on the same device as the data (bdev). + */ + struct block_device *meta_bdev; struct block_device *bdev; /* block device handle */ struct page *sb_page; |