From d9e1611e7347b41bae8894e957a398fa41162dab Mon Sep 17 00:00:00 2001 From: Joerg Roedel Date: Wed, 9 Jul 2014 15:43:11 +0200 Subject: [PATCH] iommu/amd: Don't call the inv_ctx_cb when pasid is not set up On the error path of amd_iommu_bind_pasid() we call mmu_notifier_unregister() for cleanup. This calls mn_release() which calls the users inv_ctx_cb function if one is available. Since the pasid is not set up yet there is nothing the user can to tear down in this call-back. So don't call inv_ctx_cb on the error path of amd_iommu_unbind_pasid() and make life of the users simpler. Signed-off-by: Joerg Roedel Tested-by: Oded Gabbay --- drivers/iommu/amd_iommu_v2.c | 17 ++++++++++++----- 1 file changed, 12 insertions(+), 5 deletions(-) diff --git a/drivers/iommu/amd_iommu_v2.c b/drivers/iommu/amd_iommu_v2.c index f7ca009bda67..a195c78b63c6 100644 --- a/drivers/iommu/amd_iommu_v2.c +++ b/drivers/iommu/amd_iommu_v2.c @@ -52,7 +52,8 @@ struct pasid_state { struct pri_queue pri[PRI_QUEUE_SIZE]; /* PRI tag states */ struct device_state *device_state; /* Link to our device_state */ int pasid; /* PASID index */ - bool invalid; /* Used during teardown */ + bool invalid; /* Used during setup and + teardown of the pasid */ spinlock_t lock; /* Protect pri_queues and mmu_notifer_count */ wait_queue_head_t wq; /* To wait for count == 0 */ @@ -473,13 +474,15 @@ static void mn_release(struct mmu_notifier *mn, struct mm_struct *mm) { struct pasid_state *pasid_state; struct device_state *dev_state; + bool run_inv_ctx_cb; might_sleep(); - pasid_state = mn_to_state(mn); - dev_state = pasid_state->device_state; + pasid_state = mn_to_state(mn); + dev_state = pasid_state->device_state; + run_inv_ctx_cb = !pasid_state->invalid; - if (pasid_state->device_state->inv_ctx_cb) + if (run_inv_ctx_cb && pasid_state->device_state->inv_ctx_cb) dev_state->inv_ctx_cb(dev_state->pdev, pasid_state->pasid); unbind_pasid(pasid_state); @@ -674,7 +677,8 @@ int amd_iommu_bind_pasid(struct pci_dev *pdev, int pasid, pasid_state->mm = mm; pasid_state->device_state = dev_state; pasid_state->pasid = pasid; - pasid_state->invalid = false; + pasid_state->invalid = true; /* Mark as valid only if we are + done with setting up the pasid */ pasid_state->mn.ops = &iommu_mn; if (pasid_state->mm == NULL) @@ -691,6 +695,9 @@ int amd_iommu_bind_pasid(struct pci_dev *pdev, int pasid, if (ret) goto out_clear_state; + /* Now we are ready to handle faults */ + pasid_state->invalid = false; + /* * Drop the reference to the mm_struct here. We rely on the * mmu_notifier release call-back to inform us when the mm -- 2.34.1