pnfs-obj: Bug when we are running out of bio
commit 20618b21da0796115e81906d24ff1601552701b7 upstream.
When we have a situation that the number of pages we want
to encode is bigger then the size of the bio. (Which can
currently happen only when all IO is going to a single device
.e.g group_width==1) then the IO is submitted short and we
report back only the amount of bytes we actually wrote/read
and all is fine. BUT ...
There was a bug that the current length counter was advanced
before the fail to add the extra page, and we come to a situation
that the CDB length was one-page longer then the actual bio size,
which is of course rejected by the osd-target.
While here also fix the bio size calculation, in the case
that we received more then one group of devices.
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/fs/nfs/objlayout/objio_osd.c b/fs/nfs/objlayout/objio_osd.c
index 799e8cf..1d1dc1e 100644
--- a/fs/nfs/objlayout/objio_osd.c
+++ b/fs/nfs/objlayout/objio_osd.c
@@ -587,22 +587,19 @@
}
static int _add_stripe_unit(struct objio_state *ios, unsigned *cur_pg,
- unsigned pgbase, struct _objio_per_comp *per_dev, int cur_len,
+ unsigned pgbase, struct _objio_per_comp *per_dev, int len,
gfp_t gfp_flags)
{
unsigned pg = *cur_pg;
+ int cur_len = len;
struct request_queue *q =
osd_request_queue(_io_od(ios, per_dev->dev));
- per_dev->length += cur_len;
-
if (per_dev->bio == NULL) {
- unsigned stripes = ios->layout->num_comps /
- ios->layout->mirrors_p1;
- unsigned pages_in_stripe = stripes *
+ unsigned pages_in_stripe = ios->layout->group_width *
(ios->layout->stripe_unit / PAGE_SIZE);
unsigned bio_size = (ios->ol_state.nr_pages + pages_in_stripe) /
- stripes;
+ ios->layout->group_width;
if (BIO_MAX_PAGES_KMALLOC < bio_size)
bio_size = BIO_MAX_PAGES_KMALLOC;
@@ -630,6 +627,7 @@
}
BUG_ON(cur_len);
+ per_dev->length += len;
*cur_pg = pg;
return 0;
}