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| author | NeilBrown <neilb@suse.de> | 2009-12-14 12:49:54 +1100 |
|---|---|---|
| committer | NeilBrown <neilb@suse.de> | 2009-12-14 12:51:41 +1100 |
| commit | f6af949c5672115313cc3c976d85b0533f607d7e (patch) | |
| tree | 6d00471bd4ee7c3aee67f9ad4c0a3023109b88e0 | |
| parent | 9cd30fdc33cde9ae4ac55a1ccbbb89f3f7b9b2f2 (diff) | |
| download | linux-f6af949c5672115313cc3c976d85b0533f607d7e.tar.gz linux-f6af949c5672115313cc3c976d85b0533f607d7e.tar.bz2 linux-f6af949c5672115313cc3c976d85b0533f607d7e.zip | |
md: support bitmap offset appropriate for external-metadata arrays.
For md arrays were metadata is managed externally, the kernel does not
know about a superblock so the superblock offset is 0.
If we want to have a write-intent-bitmap near the end of the
devices of such an array, we should support sector_t sized offset.
We need offset be possibly negative for when the bitmap is before
the metadata, so use loff_t instead.
Also add sanity check that bitmap does not overlap with data.
Signed-off-by: NeilBrown <neilb@suse.de>
| -rw-r--r-- | drivers/md/bitmap.c | 14 | ||||
| -rw-r--r-- | drivers/md/md.h | 6 |
2 files changed, 15 insertions, 5 deletions
diff --git a/drivers/md/bitmap.c b/drivers/md/bitmap.c index b1bcd36ca963..958865445f06 100644 --- a/drivers/md/bitmap.c +++ b/drivers/md/bitmap.c @@ -212,7 +212,7 @@ static void bitmap_checkfree(struct bitmap *bitmap, unsigned long page) */ /* IO operations when bitmap is stored near all superblocks */ -static struct page *read_sb_page(mddev_t *mddev, long offset, +static struct page *read_sb_page(mddev_t *mddev, loff_t offset, struct page *page, unsigned long index, int size) { @@ -287,14 +287,22 @@ static int write_sb_page(struct bitmap *bitmap, struct page *page, int wait) while ((rdev = next_active_rdev(rdev, mddev)) != NULL) { int size = PAGE_SIZE; - long offset = mddev->bitmap_info.offset; + loff_t offset = mddev->bitmap_info.offset; if (page->index == bitmap->file_pages-1) size = roundup(bitmap->last_page_size, bdev_logical_block_size(rdev->bdev)); /* Just make sure we aren't corrupting data or * metadata */ - if (offset < 0) { + if (mddev->external) { + /* Bitmap could be anywhere. */ + if (rdev->sb_start + offset + (page->index *(PAGE_SIZE/512)) > + rdev->data_offset && + rdev->sb_start + offset < + rdev->data_offset + mddev->dev_sectors + + (PAGE_SIZE/512)) + goto bad_alignment; + } else if (offset < 0) { /* DATA BITMAP METADATA */ if (offset + (long)(page->index * (PAGE_SIZE/512)) diff --git a/drivers/md/md.h b/drivers/md/md.h index 4b07e0ab3841..df692953a12f 100644 --- a/drivers/md/md.h +++ b/drivers/md/md.h @@ -282,11 +282,13 @@ struct mddev_s struct bitmap *bitmap; /* the bitmap for the device */ struct { struct file *file; /* the bitmap file */ - long offset; /* offset from superblock of + loff_t offset; /* offset from superblock of * start of bitmap. May be * negative, but not '0' + * For external metadata, offset + * from start of device. */ - long default_offset; /* this is the offset to use when + loff_t default_offset; /* this is the offset to use when * hot-adding a bitmap. It should * eventually be settable by sysfs. */ |