s390/pci_mmio: use follow_pfnmap API

Use the new API that can understand huge pfn mappings.

Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Peter Xu <[email protected]>
Cc: Niklas Schnelle <[email protected]>
Cc: Gerald Schaefer <[email protected]>
Cc: Heiko Carstens <[email protected]>
Cc: Vasily Gorbik <[email protected]>
Cc: Alexander Gordeev <[email protected]>
Cc: Christian Borntraeger <[email protected]>
Cc: Sven Schnelle <[email protected]>
Cc: Alex Williamson <[email protected]>
Cc: Aneesh Kumar K.V <[email protected]>
Cc: Borislav Petkov <[email protected]>
Cc: Catalin Marinas <[email protected]>
Cc: Dave Hansen <[email protected]>
Cc: David Hildenbrand <[email protected]>
Cc: Gavin Shan <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Jason Gunthorpe <[email protected]>
Cc: Matthew Wilcox <[email protected]>
Cc: Paolo Bonzini <[email protected]>
Cc: Ryan Roberts <[email protected]>
Cc: Sean Christopherson <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Will Deacon <[email protected]>
Cc: Zi Yan <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>

Author: xzpeter

arch/s390/pci/pci_mmio.c

@@ -118,12 +118,11 @@ static inline int __memcpy_toio_inuser(void __iomem *dst,
 SYSCALL_DEFINE3(s390_pci_mmio_write, unsigned long, mmio_addr,
 		const void __user *, user_buffer, size_t, length)
 {
+	struct follow_pfnmap_args args = { };
 	u8 local_buf[64];
 	void __iomem *io_addr;
 	void *buf;
 	struct vm_area_struct *vma;
-	pte_t *ptep;
-	spinlock_t *ptl;
 	long ret;
 
 	if (!zpci_is_enabled())
@@ -169,19 +168,21 @@ SYSCALL_DEFINE3(s390_pci_mmio_write, unsigned long, mmio_addr,
 	if (!(vma->vm_flags & VM_WRITE))
 		goto out_unlock_mmap;
 
-	ret = follow_pte(vma, mmio_addr, &ptep, &ptl);
+	args.address = mmio_addr;
+	args.vma = vma;
+	ret = follow_pfnmap_start(&args);
 	if (ret)
 		goto out_unlock_mmap;
 
-	io_addr = (void __iomem *)((pte_pfn(*ptep) << PAGE_SHIFT) |
+	io_addr = (void __iomem *)((args.pfn << PAGE_SHIFT) |
 			(mmio_addr & ~PAGE_MASK));
 
 	if ((unsigned long) io_addr < ZPCI_IOMAP_ADDR_BASE)
 		goto out_unlock_pt;
 
 	ret = zpci_memcpy_toio(io_addr, buf, length);
 out_unlock_pt:
-	pte_unmap_unlock(ptep, ptl);
+	follow_pfnmap_end(&args);
 out_unlock_mmap:
 	mmap_read_unlock(current->mm);
 out_free:
@@ -260,12 +261,11 @@ static inline int __memcpy_fromio_inuser(void __user *dst,
 SYSCALL_DEFINE3(s390_pci_mmio_read, unsigned long, mmio_addr,
 		void __user *, user_buffer, size_t, length)
 {
+	struct follow_pfnmap_args args = { };
 	u8 local_buf[64];
 	void __iomem *io_addr;
 	void *buf;
 	struct vm_area_struct *vma;
-	pte_t *ptep;
-	spinlock_t *ptl;
 	long ret;
 
 	if (!zpci_is_enabled())
@@ -308,11 +308,13 @@ SYSCALL_DEFINE3(s390_pci_mmio_read, unsigned long, mmio_addr,
 	if (!(vma->vm_flags & VM_WRITE))
 		goto out_unlock_mmap;
 
-	ret = follow_pte(vma, mmio_addr, &ptep, &ptl);
+	args.vma = vma;
+	args.address = mmio_addr;
+	ret = follow_pfnmap_start(&args);
 	if (ret)
 		goto out_unlock_mmap;
 
-	io_addr = (void __iomem *)((pte_pfn(*ptep) << PAGE_SHIFT) |
+	io_addr = (void __iomem *)((args.pfn << PAGE_SHIFT) |
 			(mmio_addr & ~PAGE_MASK));
 
 	if ((unsigned long) io_addr < ZPCI_IOMAP_ADDR_BASE) {
@@ -322,7 +324,7 @@ SYSCALL_DEFINE3(s390_pci_mmio_read, unsigned long, mmio_addr,
 	ret = zpci_memcpy_fromio(buf, io_addr, length);
 
 out_unlock_pt:
-	pte_unmap_unlock(ptep, ptl);
+	follow_pfnmap_end(&args);
 out_unlock_mmap:
 	mmap_read_unlock(current->mm);