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author | Keir Fraser <keir.fraser@citrix.com> | 2008-01-29 15:18:27 +0000 |
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committer | Keir Fraser <keir.fraser@citrix.com> | 2008-01-29 15:18:27 +0000 |
commit | 7b1257946080b63421a8dc59c7b3dfd67997c643 (patch) | |
tree | e6bc5b081658357374b6126d0cb2625713889796 /extras/mini-os | |
parent | 34d2cb5d8d8cbf8a469048ac6e7af831c105274b (diff) | |
download | xen-7b1257946080b63421a8dc59c7b3dfd67997c643.tar.gz xen-7b1257946080b63421a8dc59c7b3dfd67997c643.tar.bz2 xen-7b1257946080b63421a8dc59c7b3dfd67997c643.zip |
minios: Fix bug when blkfront reading into zero-mapped buffer
by just poking the page.
No need to use virtual_to_mfn() for the ring since that is a real page.
Signed-off-by: Samuel Thibault <samuel.thibault@eu.citrix.com>
Diffstat (limited to 'extras/mini-os')
-rw-r--r-- | extras/mini-os/blkfront.c | 7 |
1 files changed, 6 insertions, 1 deletions
diff --git a/extras/mini-os/blkfront.c b/extras/mini-os/blkfront.c index 7fff105635..0c77d6d1e4 100644 --- a/extras/mini-os/blkfront.c +++ b/extras/mini-os/blkfront.c @@ -88,7 +88,7 @@ struct blkfront_dev *init_blkfront(char *nodename, uint64_t *sectors, unsigned * SHARED_RING_INIT(s); FRONT_RING_INIT(&dev->ring, s, PAGE_SIZE); - dev->ring_ref = gnttab_grant_access(0,virtual_to_mfn(s),0); + dev->ring_ref = gnttab_grant_access(0,virt_to_mfn(s),0); evtchn_alloc_unbound_t op; op.dom = DOMID_SELF; @@ -274,6 +274,11 @@ void blkfront_aio(struct blkfront_aiocb *aiocbp, int write) for (j = 0; j < n; j++) { uintptr_t data = start + j * PAGE_SIZE; + if (!write) { + /* Trigger CoW if needed */ + *(char*)data = 0; + barrier(); + } aiocbp->gref[j] = req->seg[j].gref = gnttab_grant_access(0, virtual_to_mfn(data), write); req->seg[j].first_sect = 0; |