iommu/s390: Implement map_pages()/unmap_pages() instead of map()/unmap()

While s390-iommu currently implements the map_page()/unmap_page()
operations which only map/unmap a single page at a time the internal
s390_iommu_update_trans() API already supports mapping/unmapping a range
of pages at once. Take advantage of this by implementing the
map_pages()/unmap_pages() operations instead thus allowing users of the
IOMMU drivers to map multiple pages in a single call followed by
a single I/O TLB flush if needed.

Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com>
Link: https://lore.kernel.org/r/20221025115657.1666860-7-schnelle@linux.ibm.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>

diff --git a/drivers/iommu/s390-iommu.c b/drivers/iommu/s390-iommu.c
index 104dfbe..7fb512b 100644 (file)
--- a/drivers/iommu/s390-iommu.c
+++ b/drivers/iommu/s390-iommu.c
@@ -196,20 +196,15 @@ static void s390_iommu_release_device(struct device *dev)
 
 static int s390_iommu_update_trans(struct s390_domain *s390_domain,
                                   phys_addr_t pa, dma_addr_t dma_addr,
-                                  size_t size, int flags)
+                                  unsigned long nr_pages, int flags)
 {
        phys_addr_t page_addr = pa & PAGE_MASK;
        dma_addr_t start_dma_addr = dma_addr;
-       unsigned long irq_flags, nr_pages, i;
+       unsigned long irq_flags, i;
        struct zpci_dev *zdev;
        unsigned long *entry;
        int rc = 0;
 
-       if (dma_addr < s390_domain->domain.geometry.aperture_start ||
-           (dma_addr + size - 1) > s390_domain->domain.geometry.aperture_end)
-               return -EINVAL;
-
-       nr_pages = PAGE_ALIGN(size) >> PAGE_SHIFT;
        if (!nr_pages)
                return 0;
 
@@ -252,11 +247,24 @@ undo_cpu_trans:
        return rc;
 }
 
-static int s390_iommu_map(struct iommu_domain *domain, unsigned long iova,
-                         phys_addr_t paddr, size_t size, int prot, gfp_t gfp)
+static int s390_iommu_map_pages(struct iommu_domain *domain,
+                               unsigned long iova, phys_addr_t paddr,
+                               size_t pgsize, size_t pgcount,
+                               int prot, gfp_t gfp, size_t *mapped)
 {
        struct s390_domain *s390_domain = to_s390_domain(domain);
        int flags = ZPCI_PTE_VALID, rc = 0;
+       size_t size = pgcount << __ffs(pgsize);
+
+       if (pgsize != SZ_4K)
+               return -EINVAL;
+
+       if (iova < s390_domain->domain.geometry.aperture_start ||
+           (iova + size - 1) > s390_domain->domain.geometry.aperture_end)
+               return -EINVAL;
+
+       if (!IS_ALIGNED(iova | paddr, pgsize))
+               return -EINVAL;
 
        if (!(prot & IOMMU_READ))
                return -EINVAL;
@@ -265,7 +273,9 @@ static int s390_iommu_map(struct iommu_domain *domain, unsigned long iova,
                flags |= ZPCI_TABLE_PROTECTED;
 
        rc = s390_iommu_update_trans(s390_domain, paddr, iova,
-                                    size, flags);
+                                    pgcount, flags);
+       if (!rc)
+               *mapped = size;
 
        return rc;
 }
@@ -301,21 +311,27 @@ static phys_addr_t s390_iommu_iova_to_phys(struct iommu_domain *domain,
        return phys;
 }
 
-static size_t s390_iommu_unmap(struct iommu_domain *domain,
-                              unsigned long iova, size_t size,
-                              struct iommu_iotlb_gather *gather)
+static size_t s390_iommu_unmap_pages(struct iommu_domain *domain,
+                                    unsigned long iova,
+                                    size_t pgsize, size_t pgcount,
+                                    struct iommu_iotlb_gather *gather)
 {
        struct s390_domain *s390_domain = to_s390_domain(domain);
+       size_t size = pgcount << __ffs(pgsize);
        int flags = ZPCI_PTE_INVALID;
        phys_addr_t paddr;
        int rc;
 
+       if (WARN_ON(iova < s390_domain->domain.geometry.aperture_start ||
+           (iova + size - 1) > s390_domain->domain.geometry.aperture_end))
+               return 0;
+
        paddr = s390_iommu_iova_to_phys(domain, iova);
        if (!paddr)
                return 0;
 
        rc = s390_iommu_update_trans(s390_domain, paddr, iova,
-                                    size, flags);
+                                    pgcount, flags);
        if (rc)
                return 0;
 
@@ -361,8 +377,8 @@ static const struct iommu_ops s390_iommu_ops = {
        .default_domain_ops = &(const struct iommu_domain_ops) {
                .attach_dev     = s390_iommu_attach_device,
                .detach_dev     = s390_iommu_detach_device,
-               .map            = s390_iommu_map,
-               .unmap          = s390_iommu_unmap,
+               .map_pages      = s390_iommu_map_pages,
+               .unmap_pages    = s390_iommu_unmap_pages,
                .iova_to_phys   = s390_iommu_iova_to_phys,
                .free           = s390_domain_free,
        }