diff options
| author | Vitaly Kuznetsov <vkuznets@redhat.com> | 2014-12-01 14:01:13 +0100 |
|---|---|---|
| committer | Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> | 2014-12-10 12:20:07 -0500 |
| commit | ad42d391ae388bd4ce4d53e8d7b4089cfdcba411 (patch) | |
| tree | 3002687530aded859fba77ba63e5f7e1e73847fd /drivers/block/xen-blkfront.c | |
| parent | 9af8785a38d4528d6675247f873b0f1ae29f3be8 (diff) | |
| download | linux-ad42d391ae388bd4ce4d53e8d7b4089cfdcba411.tar.bz2 | |
xen/blkfront: improve protection against issuing unsupported REQ_FUA
Guard against issuing unsupported REQ_FUA and REQ_FLUSH was introduced
in d11e61583 and was factored out into blkif_request_flush_valid() in
0f1ca65ee. However:
1) This check in incomplete. In case we negotiated to feature_flush = REQ_FLUSH
and flush_op = BLKIF_OP_FLUSH_DISKCACHE (so FUA is unsupported) FUA request
will still pass the check.
2) blkif_request_flush_valid() is misnamed. It is bool but returns true when
the request is invalid.
3) When blkif_request_flush_valid() fails -EIO is being returned. It seems that
-EOPNOTSUPP is more appropriate here.
Fix all of the above issues.
This patch is based on the original patch by Laszlo Ersek and a comment by
Jeff Moyer.
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Diffstat (limited to 'drivers/block/xen-blkfront.c')
| -rw-r--r-- | drivers/block/xen-blkfront.c | 14 |
1 files changed, 8 insertions, 6 deletions
diff --git a/drivers/block/xen-blkfront.c b/drivers/block/xen-blkfront.c index 5ac312f6e0be..2e6c10371b24 100644 --- a/drivers/block/xen-blkfront.c +++ b/drivers/block/xen-blkfront.c @@ -582,12 +582,14 @@ static inline void flush_requests(struct blkfront_info *info) notify_remote_via_irq(info->irq); } -static inline bool blkif_request_flush_valid(struct request *req, - struct blkfront_info *info) +static inline bool blkif_request_flush_invalid(struct request *req, + struct blkfront_info *info) { return ((req->cmd_type != REQ_TYPE_FS) || - ((req->cmd_flags & (REQ_FLUSH | REQ_FUA)) && - !info->flush_op)); + ((req->cmd_flags & REQ_FLUSH) && + !(info->feature_flush & REQ_FLUSH)) || + ((req->cmd_flags & REQ_FUA) && + !(info->feature_flush & REQ_FUA))); } /* @@ -612,8 +614,8 @@ static void do_blkif_request(struct request_queue *rq) blk_start_request(req); - if (blkif_request_flush_valid(req, info)) { - __blk_end_request_all(req, -EIO); + if (blkif_request_flush_invalid(req, info)) { + __blk_end_request_all(req, -EOPNOTSUPP); continue; } |