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Groups > linux.kernel > #1595463
| From | Stefano Stabellini <sstabellini@kernel.org> |
|---|---|
| Newsgroups | linux.kernel |
| Subject | Re: [PATCH 4/7] xen/9pfs: connect to the backend |
| Date | 2017-03-08 20:30 +0100 |
| Message-ID | <tiPrA-2uR-9@gated-at.bofh.it> (permalink) |
| References | (1 earlier) <ti7gR-4VX-1@gated-at.bofh.it> <ti7gR-4VX-7@gated-at.bofh.it> <tioUp-PI-1@gated-at.bofh.it> <tixEm-70H-5@gated-at.bofh.it> <tiKie-7jK-9@gated-at.bofh.it> |
| Organization | linux.* mail to news gateway |
On Wed, 8 Mar 2017, Boris Ostrovsky wrote:
> >>> + ring->bytes = (void*)__get_free_pages(GFP_KERNEL | __GFP_ZERO, XEN_9PFS_RING_ORDER);
> >>> + if (ring->bytes == NULL)
> >>> + goto error;
> >>> + for (i = 0; i < (1 << XEN_9PFS_RING_ORDER); i++)
> >>> + ring->intf->ref[i] = gnttab_grant_foreign_access(dev->otherend_id, pfn_to_gfn(virt_to_pfn((void*)ring->bytes) + i), 0);
> >>> + ring->ref = gnttab_grant_foreign_access(dev->otherend_id, pfn_to_gfn(virt_to_pfn((void*)ring->intf)), 0);
> >>> + ring->ring.in = ring->bytes;
> >>> + ring->ring.out = ring->bytes + XEN_9PFS_RING_SIZE;
> >>> +
> >>> + ret = xenbus_alloc_evtchn(dev, &ring->evtchn);
> >>> + if (ret)
> >>> + goto error;
> >>> + ring->irq = bind_evtchn_to_irqhandler(ring->evtchn, xen_9pfs_front_event_handler,
> >>> + 0, "xen_9pfs-frontend", ring);
> >>> + if (ring->irq < 0) {
> >>> + xenbus_free_evtchn(dev, ring->evtchn);
> >>> + ret = ring->irq;
> >>> + goto error;
> >>> + }
> >>> return 0;
> >>> +
> >>> +error:
> >> You may need to gnttab_end_foreign_access().
> > Actually this error path is unnecessary because it will be handled by
> > xen_9pfs_front_probe, that calls xen_9pfs_front_free on errors. I'll
> > remove it.
>
>
> (It's a matter of personal preference but I think a routine should clean
> up its own mess whenever it can.)
>
> >
> >
> > +
> > + again:
> > + ret = xenbus_transaction_start(&xbt);
> > + if (ret) {
> > + xenbus_dev_fatal(dev, ret, "starting transaction");
> > + goto error;
> > + }
> > + ret = xenbus_printf(xbt, dev->nodename, "version", "%u", 1);
> > + if (ret)
> > + goto error_xenbus;
> > + ret = xenbus_printf(xbt, dev->nodename, "num-rings", "%u", priv->num_rings);
> > + if (ret)
> > + goto error_xenbus;
> > + for (i = 0; i < priv->num_rings; i++) {
> > + char str[16];
> > +
> > + priv->rings[i].priv = priv;
> > + ret = xen_9pfs_front_alloc_dataring(dev, &priv->rings[i]);
> >> Not for -EAGAIN, I think.
> > I don't think xen_9pfs_front_alloc_dataring can return EAGAIN. EAGAIN
> > can only come from xenbus_transaction_end, the case we handle below.
>
> I didn't mean that xen_9pfs_front_alloc_dataring() can return -EAGAIN. I
> was referring to...
>
> >
> >
> >>> + if (ret < 0)
> >>> + goto error_xenbus;
> >>> +
> >>> + sprintf(str, "ring-ref%u", i);
> >>> + ret = xenbus_printf(xbt, dev->nodename, str, "%d", priv->rings[i].ref);
> >>> + if (ret)
> >>> + goto error_xenbus;
> >>> +
> >>> + sprintf(str, "event-channel-%u", i);
> >>> + ret = xenbus_printf(xbt, dev->nodename, str, "%u", priv->rings[i].evtchn);
> >>> + if (ret)
> >>> + goto error_xenbus;
> >>> + }
> >>> + priv->tag = xenbus_read(xbt, dev->nodename, "tag", NULL);
> >>> + if (ret)
> >>> + goto error_xenbus;
> >>> + ret = xenbus_transaction_end(xbt, 0);
> >>> + if (ret) {
> >>> + if (ret == -EAGAIN)
> >>> + goto again;
>
> ... this.
>
> Sorry for not being clear.
You are right! I'll move the call to xen_9pfs_front_alloc_dataring out
of the xenbus loop.
Back to linux.kernel | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread
[PATCH 0/7] Xen transport for 9pfs frontend driver Stefano Stabellini <sstabellini@kernel.org> - 2017-03-06 21:10 +0100
[PATCH 1/7] xen: import new ring macros in ring.h Stefano Stabellini <sstabellini@kernel.org> - 2017-03-06 21:20 +0100
[PATCH 7/7] xen/9pfs: build 9pfs Xen transport driver Stefano Stabellini <sstabellini@kernel.org> - 2017-03-06 21:20 +0100
[PATCH 6/7] xen/9pfs: receive responses Stefano Stabellini <sstabellini@kernel.org> - 2017-03-06 21:20 +0100
Re: [PATCH 6/7] xen/9pfs: receive responses Boris Ostrovsky <boris.ostrovsky@oracle.com> - 2017-03-07 17:00 +0100
Re: [PATCH 6/7] xen/9pfs: receive responses Stefano Stabellini <sstabellini@kernel.org> - 2017-03-08 02:30 +0100
Re: [Xen-devel] [PATCH 6/7] xen/9pfs: receive responses Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> - 2017-03-08 21:20 +0100
Re: [PATCH 6/7] xen/9pfs: receive responses Stefano Stabellini <sstabellini@kernel.org> - 2017-03-08 06:30 +0100
Re: [PATCH 6/7] xen/9pfs: receive responses Boris Ostrovsky <boris.ostrovsky@oracle.com> - 2017-03-08 15:40 +0100
Re: [PATCH 6/7] xen/9pfs: receive responses Stefano Stabellini <sstabellini@kernel.org> - 2017-03-08 20:30 +0100
[PATCH 2/7] xen: introduce the header file for the Xen 9pfs transport protocol Stefano Stabellini <sstabellini@kernel.org> - 2017-03-06 21:20 +0100
Re: [PATCH 2/7] xen: introduce the header file for the Xen 9pfs transport protocol Stefano Stabellini <sstabellini@kernel.org> - 2017-03-06 22:40 +0100
Re: [PATCH 2/7] xen: introduce the header file for the Xen 9pfs transport protocol Boris Ostrovsky <boris.ostrovsky@oracle.com> - 2017-03-06 22:50 +0100
Re: [PATCH 2/7] xen: introduce the header file for the Xen 9pfs transport protocol Boris Ostrovsky <boris.ostrovsky@oracle.com> - 2017-03-06 23:40 +0100
[PATCH 4/7] xen/9pfs: connect to the backend Stefano Stabellini <sstabellini@kernel.org> - 2017-03-06 21:20 +0100
Re: [PATCH 4/7] xen/9pfs: connect to the backend Boris Ostrovsky <boris.ostrovsky@oracle.com> - 2017-03-07 16:10 +0100
Re: [PATCH 4/7] xen/9pfs: connect to the backend Stefano Stabellini <sstabellini@kernel.org> - 2017-03-08 01:30 +0100
Re: [PATCH 4/7] xen/9pfs: connect to the backend Boris Ostrovsky <boris.ostrovsky@oracle.com> - 2017-03-08 15:00 +0100
Re: [PATCH 4/7] xen/9pfs: connect to the backend Stefano Stabellini <sstabellini@kernel.org> - 2017-03-08 20:30 +0100
Re: [Xen-devel] [PATCH 4/7] xen/9pfs: connect to the backend Julien Grall <julien.grall@arm.com> - 2017-03-07 20:00 +0100
Re: [Xen-devel] [PATCH 4/7] xen/9pfs: connect to the backend Stefano Stabellini <sstabellini@kernel.org> - 2017-03-08 03:20 +0100
Re: [Xen-devel] [PATCH 4/7] xen/9pfs: connect to the backend Julien Grall <julien.grall@arm.com> - 2017-03-08 13:40 +0100
Re: [Xen-devel] [PATCH 4/7] xen/9pfs: connect to the backend Stefano Stabellini <sstabellini@kernel.org> - 2017-03-08 20:10 +0100
[PATCH 3/7] xen/9pfs: introduce Xen 9pfs transport driver Stefano Stabellini <sstabellini@kernel.org> - 2017-03-06 21:20 +0100
[PATCH 5/7] xen/9pfs: send requests to the backend Stefano Stabellini <sstabellini@kernel.org> - 2017-03-06 21:20 +0100
Re: [PATCH 5/7] xen/9pfs: send requests to the backend Boris Ostrovsky <boris.ostrovsky@oracle.com> - 2017-03-07 17:40 +0100
Re: [PATCH 5/7] xen/9pfs: send requests to the backend Stefano Stabellini <sstabellini@kernel.org> - 2017-03-08 02:00 +0100
Re: [PATCH 5/7] xen/9pfs: send requests to the backend Boris Ostrovsky <boris.ostrovsky@oracle.com> - 2017-03-08 15:10 +0100
Re: [PATCH 5/7] xen/9pfs: send requests to the backend Stefano Stabellini <sstabellini@kernel.org> - 2017-03-08 20:50 +0100
Re: [PATCH 5/7] xen/9pfs: send requests to the backend Boris Ostrovsky <boris.ostrovsky@oracle.com> - 2017-03-08 21:10 +0100
Re: [PATCH 5/7] xen/9pfs: send requests to the backend Boris Ostrovsky <boris.ostrovsky@oracle.com> - 2017-03-08 22:10 +0100
Re: [PATCH 5/7] xen/9pfs: send requests to the backend Stefano Stabellini <sstabellini@kernel.org> - 2017-03-08 22:30 +0100
Re: [Xen-devel] [PATCH 1/7] xen: import new ring macros in ring.h Julien Grall <julien.grall@arm.com> - 2017-03-07 20:20 +0100
Re: [Xen-devel] [PATCH 1/7] xen: import new ring macros in ring.h Stefano Stabellini <sstabellini@kernel.org> - 2017-03-08 01:30 +0100
Re: [Xen-devel] [PATCH 1/7] xen: import new ring macros in ring.h Julien Grall <julien.grall@arm.com> - 2017-03-08 12:50 +0100
Re: [Xen-devel] [PATCH 0/7] Xen transport for 9pfs frontend driver Roger Pau Monné <roger.pau@citrix.com> - 2017-03-07 17:50 +0100
Re: [Xen-devel] [PATCH 0/7] Xen transport for 9pfs frontend driver Stefano Stabellini <sstabellini@kernel.org> - 2017-03-07 19:30 +0100
Re: [Xen-devel] [PATCH 0/7] Xen transport for 9pfs frontend driver Roger Pau Monné <roger.pau@citrix.com> - 2017-03-09 04:10 +0100
Re: [Xen-devel] [PATCH 0/7] Xen transport for 9pfs frontend driver Stefano Stabellini <sstabellini@kernel.org> - 2017-03-13 23:40 +0100
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