Re: [PATCH v2 21/24] iommu/dma: Factor out flush queue init

From: Lu Baolu
Date: Fri Jul 30 2021 - 02:13:48 EST


On 7/28/21 11:58 PM, Robin Murphy wrote:
Factor out flush queue setup from the initial domain init so that we
can potentially trigger it from sysfs later on in a domain's lifetime.

Signed-off-by: Robin Murphy <robin.murphy@xxxxxxx>
---
drivers/iommu/dma-iommu.c | 30 ++++++++++++++++++++----------
include/linux/dma-iommu.h | 9 ++++++---
2 files changed, 26 insertions(+), 13 deletions(-)

diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c
index 7f3968865387..304a3ec71223 100644
--- a/drivers/iommu/dma-iommu.c
+++ b/drivers/iommu/dma-iommu.c
@@ -310,6 +310,25 @@ static bool dev_is_untrusted(struct device *dev)
return dev_is_pci(dev) && to_pci_dev(dev)->untrusted;
}
+int iommu_dma_init_fq(struct iommu_domain *domain)
+{
+ struct iommu_dma_cookie *cookie = domain->iova_cookie;
+
+ if (domain->type != IOMMU_DOMAIN_DMA_FQ)
+ return -EINVAL;
+ if (cookie->fq_domain)
+ return 0;
+
+ if (init_iova_flush_queue(&cookie->iovad, iommu_dma_flush_iotlb_all,
+ iommu_dma_entry_dtor)) {
+ pr_warn("iova flush queue initialization failed\n");
+ domain->type = IOMMU_DOMAIN_DMA;
+ return -ENODEV;
+ }
+ cookie->fq_domain = domain;
+ return 0;
+}
+
/**
* iommu_dma_init_domain - Initialise a DMA mapping domain
* @domain: IOMMU domain previously prepared by iommu_get_dma_cookie()
@@ -362,16 +381,7 @@ static int iommu_dma_init_domain(struct iommu_domain *domain, dma_addr_t base,
}
init_iova_domain(iovad, 1UL << order, base_pfn);
-
- if (domain->type == IOMMU_DOMAIN_DMA_FQ && !cookie->fq_domain) {
- if (init_iova_flush_queue(iovad, iommu_dma_flush_iotlb_all,
- iommu_dma_entry_dtor)) {
- pr_warn("iova flush queue initialization failed\n");
- domain->type = IOMMU_DOMAIN_DMA;
- } else {
- cookie->fq_domain = domain;
- }
- }
+ iommu_dma_init_fq(domain);
return iova_reserve_iommu_regions(dev, domain);
}
diff --git a/include/linux/dma-iommu.h b/include/linux/dma-iommu.h
index 758ca4694257..81ab647f1618 100644
--- a/include/linux/dma-iommu.h
+++ b/include/linux/dma-iommu.h
@@ -20,6 +20,7 @@ void iommu_put_dma_cookie(struct iommu_domain *domain);
/* Setup call for arch DMA mapping code */
void iommu_setup_dma_ops(struct device *dev, u64 dma_base, u64 dma_limit);
+int iommu_dma_init_fq(struct iommu_domain *domain);
/* The DMA API isn't _quite_ the whole story, though... */
/*
@@ -37,9 +38,6 @@ void iommu_dma_compose_msi_msg(struct msi_desc *desc,
void iommu_dma_get_resv_regions(struct device *dev, struct list_head *list);
-void iommu_dma_free_cpu_cached_iovas(unsigned int cpu,
- struct iommu_domain *domain);
-
extern bool iommu_dma_forcedac;
#else /* CONFIG_IOMMU_DMA */
@@ -54,6 +52,11 @@ static inline void iommu_setup_dma_ops(struct device *dev, u64 dma_base,
{
}
+static inline int iommu_dma_init_fq(struct iommu_domain *domain)
+{
+ return -EINVAL;
+}
+
static inline int iommu_get_dma_cookie(struct iommu_domain *domain)
{
return -ENODEV;



Reviewed-by: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx>

Best regards,
baolu