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| author | Roger Pau Monne <roger.pau@citrix.com> | 2012-11-02 16:43:04 +0100 |
|---|---|---|
| committer | Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> | 2012-11-04 10:35:40 -0500 |
| commit | cb5bd4d19b46c220b1ac8462a3da01767dd99488 (patch) | |
| tree | 1b22151771a90480d0d4790521b9432f46f1e32a /drivers/block/xen-blkback | |
| parent | 0a8704a51f386cab7394e38ff1d66eef924d8ab8 (diff) | |
| download | linux-cb5bd4d19b46c220b1ac8462a3da01767dd99488.tar.bz2 | |
xen/blkback: persistent-grants fixes
This patch contains fixes for persistent grants implementation v2:
* handle == 0 is a valid handle, so initialize grants in blkback
setting the handle to BLKBACK_INVALID_HANDLE instead of 0. Reported
by Konrad Rzeszutek Wilk.
* new_map is a boolean, use "true" or "false" instead of 1 and 0.
Reported by Konrad Rzeszutek Wilk.
* blkfront announces the persistent-grants feature as
feature-persistent-grants, use feature-persistent instead which is
consistent with blkback and the public Xen headers.
* Add a consistency check in blkfront to make sure we don't try to
access segments that have not been set.
Reported-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Roger Pau Monne <roger.pau@citrix.com>
[v1: The new_map int->bool had already been changed]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Diffstat (limited to 'drivers/block/xen-blkback')
| -rw-r--r-- | drivers/block/xen-blkback/blkback.c | 9 | ||||
| -rw-r--r-- | drivers/block/xen-blkback/xenbus.c | 2 |
2 files changed, 7 insertions, 4 deletions
diff --git a/drivers/block/xen-blkback/blkback.c b/drivers/block/xen-blkback/blkback.c index d7dd5cbdac5f..a05961683efa 100644 --- a/drivers/block/xen-blkback/blkback.c +++ b/drivers/block/xen-blkback/blkback.c @@ -512,7 +512,7 @@ static int xen_blkbk_map(struct blkif_request *req, * not mapped but we have room for it */ new_map = true; - persistent_gnt = kzalloc( + persistent_gnt = kmalloc( sizeof(struct persistent_gnt), GFP_KERNEL); if (!persistent_gnt) @@ -523,6 +523,7 @@ static int xen_blkbk_map(struct blkif_request *req, return -ENOMEM; } persistent_gnt->gnt = req->u.rw.seg[i].gref; + persistent_gnt->handle = BLKBACK_INVALID_HANDLE; pages_to_gnt[segs_to_map] = persistent_gnt->page; @@ -584,7 +585,8 @@ static int xen_blkbk_map(struct blkif_request *req, */ bitmap_zero(pending_req->unmap_seg, BLKIF_MAX_SEGMENTS_PER_REQUEST); for (i = 0, j = 0; i < nseg; i++) { - if (!persistent_gnts[i] || !persistent_gnts[i]->handle) { + if (!persistent_gnts[i] || + persistent_gnts[i]->handle == BLKBACK_INVALID_HANDLE) { /* This is a newly mapped grant */ BUG_ON(j >= segs_to_map); if (unlikely(map[j].status != 0)) { @@ -601,7 +603,8 @@ static int xen_blkbk_map(struct blkif_request *req, } } if (persistent_gnts[i]) { - if (!persistent_gnts[i]->handle) { + if (persistent_gnts[i]->handle == + BLKBACK_INVALID_HANDLE) { /* * If this is a new persistent grant * save the handler diff --git a/drivers/block/xen-blkback/xenbus.c b/drivers/block/xen-blkback/xenbus.c index b2250265308a..a03ecbb0044c 100644 --- a/drivers/block/xen-blkback/xenbus.c +++ b/drivers/block/xen-blkback/xenbus.c @@ -760,7 +760,7 @@ static int connect_ring(struct backend_info *be) return -1; } err = xenbus_gather(XBT_NIL, dev->otherend, - "feature-persistent-grants", "%u", + "feature-persistent", "%u", &pers_grants, NULL); if (err) pers_grants = 0; |