From a175a67d306ab3fd0e140595f49290b80c909ae8 Mon Sep 17 00:00:00 2001 From: Oleksandr Tyshchenko Date: Wed, 23 Aug 2017 17:31:42 +0300 Subject: [PATCH] iommu/ipmmu-vmsa: Rereserving a free context before setting up a pagetable Reserving a free context is both quicker and more likely to fail (due to limited hardware resources) than setting up a pagetable. What is more the pagetable init/cleanup code could require the context to be set up. Signed-off-by: Oleksandr Tyshchenko CC: Robin Murphy CC: Laurent Pinchart Reviewed-by: Robin Murphy Reviewed-by: Laurent Pinchart CC: Joerg Roedel Signed-off-by: Joerg Roedel --- drivers/iommu/ipmmu-vmsa.c | 42 +++++++++++++++++++------------------- 1 file changed, 21 insertions(+), 21 deletions(-) diff --git a/drivers/iommu/ipmmu-vmsa.c b/drivers/iommu/ipmmu-vmsa.c index 5a350582f359..1711fd306d33 100644 --- a/drivers/iommu/ipmmu-vmsa.c +++ b/drivers/iommu/ipmmu-vmsa.c @@ -324,6 +324,19 @@ static int ipmmu_domain_allocate_context(struct ipmmu_vmsa_device *mmu, return ret; } +static void ipmmu_domain_free_context(struct ipmmu_vmsa_device *mmu, + unsigned int context_id) +{ + unsigned long flags; + + spin_lock_irqsave(&mmu->lock, flags); + + clear_bit(context_id, mmu->ctx); + mmu->domains[context_id] = NULL; + + spin_unlock_irqrestore(&mmu->lock, flags); +} + static int ipmmu_domain_init_context(struct ipmmu_vmsa_domain *domain) { u64 ttbr; @@ -353,22 +366,22 @@ static int ipmmu_domain_init_context(struct ipmmu_vmsa_domain *domain) */ domain->cfg.iommu_dev = domain->mmu->dev; - domain->iop = alloc_io_pgtable_ops(ARM_32_LPAE_S1, &domain->cfg, - domain); - if (!domain->iop) - return -EINVAL; - /* * Find an unused context. */ ret = ipmmu_domain_allocate_context(domain->mmu, domain); - if (ret == IPMMU_CTX_MAX) { - free_io_pgtable_ops(domain->iop); + if (ret == IPMMU_CTX_MAX) return -EBUSY; - } domain->context_id = ret; + domain->iop = alloc_io_pgtable_ops(ARM_32_LPAE_S1, &domain->cfg, + domain); + if (!domain->iop) { + ipmmu_domain_free_context(domain->mmu, domain->context_id); + return -EINVAL; + } + /* TTBR0 */ ttbr = domain->cfg.arm_lpae_s1_cfg.ttbr[0]; ipmmu_ctx_write(domain, IMTTLBR0, ttbr); @@ -409,19 +422,6 @@ static int ipmmu_domain_init_context(struct ipmmu_vmsa_domain *domain) return 0; } -static void ipmmu_domain_free_context(struct ipmmu_vmsa_device *mmu, - unsigned int context_id) -{ - unsigned long flags; - - spin_lock_irqsave(&mmu->lock, flags); - - clear_bit(context_id, mmu->ctx); - mmu->domains[context_id] = NULL; - - spin_unlock_irqrestore(&mmu->lock, flags); -} - static void ipmmu_domain_destroy_context(struct ipmmu_vmsa_domain *domain) { /*