On Mon, Jul 09, 2018 at 01:22:58PM +0800, Lu Baolu wrote:
> The obsolete per iommu pasid tables are no longer used. Hence,
> clean up them.
>
> Cc: Ashok Raj <ashok....@intel.com>
> Cc: Jacob Pan <jacob.jun....@linux.intel.com>
> Cc: Kevin Tian <kevin.t...@intel.com>
> Cc: Liu Yi L <yi.l....@intel.com>
> Signed-off-by: Lu Baolu <baolu...@linux.intel.com>
> Reviewed-by: Liu Yi L <yi.l....@intel.com>
> ---
> drivers/iommu/intel-iommu.c | 6 +++---
> drivers/iommu/intel-svm.c | 17 ++---------------
> include/linux/intel-iommu.h | 5 ++---
> 3 files changed, 7 insertions(+), 21 deletions(-)
>
> diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c
> index f8609b5..9a88081 100644
> --- a/drivers/iommu/intel-iommu.c
> +++ b/drivers/iommu/intel-iommu.c
> @@ -1755,7 +1755,7 @@ static void free_dmar_iommu(struct intel_iommu *iommu)
> if (pasid_enabled(iommu)) {
> if (ecap_prs(iommu->ecap))
> intel_svm_finish_prq(iommu);
> - intel_svm_free_pasid_tables(iommu);
> + intel_svm_exit(iommu);
> }
> #endif
> }
> @@ -3336,7 +3336,7 @@ static int __init init_dmars(void)
> hw_pass_through = 0;
> #ifdef CONFIG_INTEL_IOMMU_SVM
> if (pasid_enabled(iommu))
> - intel_svm_alloc_pasid_tables(iommu);
> + intel_svm_init(iommu);
> #endif
> }
>
> @@ -4330,7 +4330,7 @@ static int intel_iommu_add(struct dmar_drhd_unit *dmaru)
>
> #ifdef CONFIG_INTEL_IOMMU_SVM
> if (pasid_enabled(iommu))
> - intel_svm_alloc_pasid_tables(iommu);
> + intel_svm_init(iommu);
> #endif
>
> if (dmaru->ignored) {
> diff --git a/drivers/iommu/intel-svm.c b/drivers/iommu/intel-svm.c
> index a253cde..eb30836 100644
> --- a/drivers/iommu/intel-svm.c
> +++ b/drivers/iommu/intel-svm.c
> @@ -38,7 +38,7 @@ struct pasid_state_entry {
> u64 val;
> };
>
> -int intel_svm_alloc_pasid_tables(struct intel_iommu *iommu)
> +int intel_svm_init(struct intel_iommu *iommu)
> {
> struct page *pages;
> int order;
> @@ -63,15 +63,6 @@ int intel_svm_alloc_pasid_tables(struct intel_iommu *iommu)
> iommu->pasid_max = 0x20000;
>
> order = get_order(sizeof(struct pasid_entry) * iommu->pasid_max);
> - pages = alloc_pages(GFP_KERNEL | __GFP_ZERO, order);
> - if (!pages) {
> - pr_warn("IOMMU: %s: Failed to allocate PASID table\n",
> - iommu->name);
> - return -ENOMEM;
> - }
> - iommu->pasid_table = page_address(pages);
> - pr_info("%s: Allocated order %d PASID table.\n", iommu->name, order);
> -
> if (ecap_dis(iommu->ecap)) {
> /* Just making it explicit... */
> BUILD_BUG_ON(sizeof(struct pasid_entry) != sizeof(struct
> pasid_state_entry));
Then do we still need the so-called pasid state table? I tried to
find out what it did before but I failed since I see that the bit 27
of the extended cap is marked as reserved now in the latest vt-d spec
(then ecap_dis could be meaningless too).
Asked since if we don't need both the per-iommu pasid table and the
pasid state table, then maybe we don't need intel_svm_init() at all?
> @@ -86,14 +77,10 @@ int intel_svm_alloc_pasid_tables(struct intel_iommu
> *iommu)
> return 0;
> }
>
> -int intel_svm_free_pasid_tables(struct intel_iommu *iommu)
> +int intel_svm_exit(struct intel_iommu *iommu)
Same thing applies to this exit() function - after we removed the
per-iommu idr, per-iommu pasid table, and (possibly obsolete)
per-iommu pasid state table, do we need that at all?
Thanks,
> {
> int order = get_order(sizeof(struct pasid_entry) * iommu->pasid_max);
>
> - if (iommu->pasid_table) {
> - free_pages((unsigned long)iommu->pasid_table, order);
> - iommu->pasid_table = NULL;
> - }
> if (iommu->pasid_state_table) {
> free_pages((unsigned long)iommu->pasid_state_table, order);
> iommu->pasid_state_table = NULL;
> diff --git a/include/linux/intel-iommu.h b/include/linux/intel-iommu.h
> index e7901d4..3c43882 100644
> --- a/include/linux/intel-iommu.h
> +++ b/include/linux/intel-iommu.h
> @@ -453,7 +453,6 @@ struct intel_iommu {
> * devices away to userspace processes (e.g. for DPDK) and don't
> * want to trust that userspace will use *only* the PASID it was
> * told to. But while it's all driver-arbitrated, we're fine. */
> - struct pasid_entry *pasid_table;
> struct pasid_state_entry *pasid_state_table;
> struct page_req_dsc *prq;
> unsigned char prq_name[16]; /* Name for PRQ interrupt */
> @@ -526,8 +525,8 @@ int for_each_device_domain(int (*fn)(struct
> device_domain_info *info,
> void *data), void *data);
>
> #ifdef CONFIG_INTEL_IOMMU_SVM
> -extern int intel_svm_alloc_pasid_tables(struct intel_iommu *iommu);
> -extern int intel_svm_free_pasid_tables(struct intel_iommu *iommu);
> +int intel_svm_init(struct intel_iommu *iommu);
> +int intel_svm_exit(struct intel_iommu *iommu);
> extern int intel_svm_enable_prq(struct intel_iommu *iommu);
> extern int intel_svm_finish_prq(struct intel_iommu *iommu);
>
> --
> 2.7.4
>
> _______________________________________________
> iommu mailing list
> io...@lists.linux-foundation.org
> https://lists.linuxfoundation.org/mailman/listinfo/iommu
--
Peter Xu
