diff options
| author | Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> | 2011-10-12 16:23:30 -0400 |
|---|---|---|
| committer | Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> | 2011-11-18 13:28:01 -0500 |
| commit | 5ea42986694a96542644f9cae8b122d3a00c508f (patch) | |
| tree | dd74685d8cd41e39ad14e708cb6e00e0ed016fb1 /drivers/block/xen-blkback/blkback.c | |
| parent | 97e36834f5a106459ab1b290e663a4eb6264639e (diff) | |
xen/blk[front|back]: Enhance discard support with secure erasing support.
Part of the blkdev_issue_discard(xx) operation is that it can also
issue a secure discard operation that will permanantly remove the
sectors in question. We advertise that we can support that via the
'discard-secure' attribute and on the request, if the 'secure' bit
is set, we will attempt to pass in REQ_DISCARD | REQ_SECURE.
CC: Li Dongyang <lidongyang@novell.com>
[v1: Used 'flag' instead of 'secure:1' bit]
[v2: Use 'reserved' uint8_t instead of adding a new value]
[v3: Check for nseg when mapping instead of operation]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Diffstat (limited to 'drivers/block/xen-blkback/blkback.c')
| -rw-r--r-- | drivers/block/xen-blkback/blkback.c | 18 |
1 files changed, 12 insertions, 6 deletions
diff --git a/drivers/block/xen-blkback/blkback.c b/drivers/block/xen-blkback/blkback.c index d7104abc8b7..9d2261b02f2 100644 --- a/drivers/block/xen-blkback/blkback.c +++ b/drivers/block/xen-blkback/blkback.c @@ -422,13 +422,16 @@ static void xen_blk_discard(struct xen_blkif *blkif, struct blkif_request *req) int status = BLKIF_RSP_OKAY; struct block_device *bdev = blkif->vbd.bdev; - if (blkif->blk_backend_type == BLKIF_BACKEND_PHY) + if (blkif->blk_backend_type == BLKIF_BACKEND_PHY) { + unsigned long secure = (blkif->vbd.discard_secure && + (req->u.discard.flag & BLKIF_DISCARD_SECURE)) ? + BLKDEV_DISCARD_SECURE : 0; /* just forward the discard request */ err = blkdev_issue_discard(bdev, req->u.discard.sector_number, req->u.discard.nr_sectors, - GFP_KERNEL, 0); - else if (blkif->blk_backend_type == BLKIF_BACKEND_FILE) { + GFP_KERNEL, secure); + } else if (blkif->blk_backend_type == BLKIF_BACKEND_FILE) { /* punch a hole in the backing file */ struct loop_device *lo = bdev->bd_disk->private_data; struct file *file = lo->lo_backing_file; @@ -643,8 +646,11 @@ static int dispatch_rw_block_io(struct xen_blkif *blkif, break; } - /* Check that the number of segments is sane. */ - nseg = req->u.rw.nr_segments; + if (unlikely(operation == REQ_DISCARD)) + nseg = 0; + else + /* Check that the number of segments is sane. */ + nseg = req->u.rw.nr_segments; if (unlikely(nseg == 0 && operation != WRITE_FLUSH && operation != REQ_DISCARD) || @@ -708,7 +714,7 @@ static int dispatch_rw_block_io(struct xen_blkif *blkif, * the hypercall to unmap the grants - that is all done in * xen_blkbk_unmap. */ - if (operation != REQ_DISCARD && xen_blkbk_map(req, pending_req, seg)) + if (nseg && xen_blkbk_map(req, pending_req, seg)) goto fail_flush; /* |