From mboxrd@z Thu Jan 1 00:00:00 1970 From: Robin Murphy Subject: Re: [PATCH v7 07/10] iommu/dma-reserved-iommu: delete bindings in iommu_free_reserved_iova_domain Date: Wed, 20 Apr 2016 18:05:27 +0100 Message-ID: <5717B6D7.4010307@arm.com> References: <1461084994-2355-1-git-send-email-eric.auger@linaro.org> <1461084994-2355-8-git-send-email-eric.auger@linaro.org> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii"; Format="flowed" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1461084994-2355-8-git-send-email-eric.auger-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: iommu-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org Errors-To: iommu-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org To: Eric Auger , eric.auger-qxv4g6HH51o@public.gmane.org, alex.williamson-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org, will.deacon-5wv7dgnIgG8@public.gmane.org, joro-zLv9SwRftAIdnm+yROfE0A@public.gmane.org, tglx-hfZtesqFncYOwBW4kG4KsQ@public.gmane.org, jason-NLaQJdtUoK4Be96aLqz0jA@public.gmane.org, marc.zyngier-5wv7dgnIgG8@public.gmane.org, christoffer.dall-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org, linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org Cc: julien.grall-5wv7dgnIgG8@public.gmane.org, patches-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org, p.fedin-Sze3O3UU22JBDgjK7y7TUQ@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, iommu-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org, pranav.sawargaonkar-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org List-Id: iommu@lists.linux-foundation.org On 19/04/16 17:56, Eric Auger wrote: > Now reserved bindings can exist, destroy them when destroying > the reserved iova domain. iommu_map is not supposed to be atomic, > hence the extra complexity in the locking. > > Signed-off-by: Eric Auger > > --- > v6 -> v7: > - remove [PATCH v6 7/7] dma-reserved-iommu: iommu_unmap_reserved and > destroy the bindings in iommu_free_reserved_iova_domain > > v5 -> v6: > - use spin_lock instead of mutex > > v3 -> v4: > - previously "iommu/arm-smmu: relinquish reserved resources on > domain deletion" > --- > drivers/iommu/dma-reserved-iommu.c | 34 ++++++++++++++++++++++++++++------ > 1 file changed, 28 insertions(+), 6 deletions(-) > > diff --git a/drivers/iommu/dma-reserved-iommu.c b/drivers/iommu/dma-reserved-iommu.c > index 426d339..2522235 100644 > --- a/drivers/iommu/dma-reserved-iommu.c > +++ b/drivers/iommu/dma-reserved-iommu.c > @@ -157,14 +157,36 @@ void iommu_free_reserved_iova_domain(struct iommu_domain *domain) > unsigned long flags; > int ret = 0; > > - spin_lock_irqsave(&domain->reserved_lock, flags); > - > - rid = (struct reserved_iova_domain *)domain->reserved_iova_cookie; > - if (!rid) { > - ret = -EINVAL; > - goto unlock; > + while (1) { > + struct iommu_reserved_binding *b; > + struct rb_node *node; > + dma_addr_t iova; > + size_t size; > + > + spin_lock_irqsave(&domain->reserved_lock, flags); > + > + rid = (struct reserved_iova_domain *) > + domain->reserved_iova_cookie; Same comment about casting as before. > + if (!rid) { > + ret = -EINVAL; > + goto unlock; > + } > + > + node = rb_first(&domain->reserved_binding_list); > + if (!node) > + break; > + b = rb_entry(node, struct iommu_reserved_binding, node); > + > + iova = b->iova; > + size = b->size; > + > + while (!kref_put(&b->kref, reserved_binding_release)) > + ; Since you're freeing the thing anyway, why not just call the function directly? > + spin_unlock_irqrestore(&domain->reserved_lock, flags); > + iommu_unmap(domain, iova, size); > } > > + domain->reserved_binding_list = RB_ROOT; > domain->reserved_iova_cookie = NULL; > unlock: > spin_unlock_irqrestore(&domain->reserved_lock, flags); >