device-dax: make align a per-device property

Introduce @align to struct dev_dax.

When creating a new device, we still initialize to the default dax_region
@align. Child devices belonging to a region may wish to keep a different
alignment property instead of a global region-defined one.

Signed-off-by: Joao Martins <[e-mail]>
Signed-off-by: Dan Williams <[e-mail]>
Signed-off-by: Andrew Morton <[e-mail]>
Cc: Andy Lutomirski <[e-mail]>
Cc: Ard Biesheuvel <[e-mail]>
Cc: Ard Biesheuvel <[e-mail]>
Cc: Benjamin Herrenschmidt <[e-mail]>
Cc: Ben Skeggs <[e-mail]>
Cc: Bjorn Helgaas <[e-mail]>
Cc: Borislav Petkov <[e-mail]>
Cc: Boris Ostrovsky <[e-mail]>
Cc: Brice Goglin <[e-mail]>
Cc: Catalin Marinas <[e-mail]>
Cc: Daniel Vetter <[e-mail]>
Cc: Dave Hansen <[e-mail]>
Cc: Dave Jiang <[e-mail]>
Cc: David Airlie <[e-mail]>
Cc: David Hildenbrand <[e-mail]>
Cc: Greg Kroah-Hartman <[e-mail]>
Cc: "H. Peter Anvin" <[e-mail]>
Cc: Hulk Robot <[e-mail]>
Cc: Ingo Molnar <[e-mail]>
Cc: Ira Weiny <[e-mail]>
Cc: Jason Gunthorpe <[e-mail]>
Cc: Jason Yan <[e-mail]>
Cc: Jeff Moyer <[e-mail]>
Cc: "Jérôme Glisse" <[e-mail]>
Cc: Jia He <[e-mail]>
Cc: Jonathan Cameron <[e-mail]>
Cc: Juergen Gross <[e-mail]>
Cc: kernel test robot <[e-mail]>
Cc: Michael Ellerman <[e-mail]>
Cc: Mike Rapoport <[e-mail]>
Cc: Paul Mackerras <[e-mail]>
Cc: Pavel Tatashin <[e-mail]>
Cc: Peter Zijlstra <[e-mail]>
Cc: "Rafael J. Wysocki" <[e-mail]>
Cc: Randy Dunlap <[e-mail]>
Cc: Stefano Stabellini <[e-mail]>
Cc: Thomas Gleixner <[e-mail]>
Cc: Tom Lendacky <[e-mail]>
Cc: Vishal Verma <[e-mail]>
Cc: Vivek Goyal <[e-mail]>
Cc: Wei Yang <[e-mail]>
Cc: Will Deacon <[e-mail]>
Link: https://lkml.kernel.org/r/[e-mail]
Link: https://lore.kernel.org/r/[e-mail]
Link: https://lkml.kernel.org/r/[e-mail]
Signed-off-by: Linus Torvalds <[e-mail]>

drivers/dax/bus.c

···
 
 	dev_dax->dax_dev = dax_dev;
 	dev_dax->target_node = dax_region->target_node;
+	dev_dax->align = dax_region->align;
 	ida_init(&dev_dax->ida);
 	kref_get(&dax_region->kref);
 

drivers/dax/dax-private.h

···
 struct dev_dax {
 	struct dax_region *region;
 	struct dax_device *dax_dev;
+	unsigned int align;
 	int target_node;
 	int id;
 	struct ida ida;
···
 {
 	return container_of(dev, struct dax_mapping, dev);
 }
+
+phys_addr_t dax_pgoff_to_phys(struct dev_dax *dev_dax, pgoff_t pgoff, unsigned long size);
 #endif

drivers/dax/device.c

···
 static int check_vma(struct dev_dax *dev_dax, struct vm_area_struct *vma,
 		const char *func)
 {
-	struct dax_region *dax_region = dev_dax->region;
 	struct device *dev = &dev_dax->dev;
 	unsigned long mask;
 
···
 		return -EINVAL;
 	}
 
-	mask = dax_region->align - 1;
+	mask = dev_dax->align - 1;
 	if (vma->vm_start & mask || vma->vm_end & mask) {
 		dev_info_ratelimited(dev,
 				"%s: %s: fail, unaligned vma (%#lx - %#lx, %#lx)\n",
···
 				struct vm_fault *vmf, pfn_t *pfn)
 {
 	struct device *dev = &dev_dax->dev;
-	struct dax_region *dax_region;
 	phys_addr_t phys;
 	unsigned int fault_size = PAGE_SIZE;
 
 	if (check_vma(dev_dax, vmf->vma, __func__))
 		return VM_FAULT_SIGBUS;
 
-	dax_region = dev_dax->region;
-	if (dax_region->align > PAGE_SIZE) {
+	if (dev_dax->align > PAGE_SIZE) {
 		dev_dbg(dev, "alignment (%#x) > fault size (%#x)\n",
-			dax_region->align, fault_size);
+			dev_dax->align, fault_size);
 		return VM_FAULT_SIGBUS;
 	}
 
-	if (fault_size != dax_region->align)
+	if (fault_size != dev_dax->align)
 		return VM_FAULT_SIGBUS;
 
 	phys = dax_pgoff_to_phys(dev_dax, vmf->pgoff, PAGE_SIZE);
···
 {
 	unsigned long pmd_addr = vmf->address & PMD_MASK;
 	struct device *dev = &dev_dax->dev;
-	struct dax_region *dax_region;
 	phys_addr_t phys;
 	pgoff_t pgoff;
 	unsigned int fault_size = PMD_SIZE;
···
 	if (check_vma(dev_dax, vmf->vma, __func__))
 		return VM_FAULT_SIGBUS;
 
-	dax_region = dev_dax->region;
-	if (dax_region->align > PMD_SIZE) {
+	if (dev_dax->align > PMD_SIZE) {
 		dev_dbg(dev, "alignment (%#x) > fault size (%#x)\n",
-			dax_region->align, fault_size);
+			dev_dax->align, fault_size);
 		return VM_FAULT_SIGBUS;
 	}
 
-	if (fault_size < dax_region->align)
+	if (fault_size < dev_dax->align)
 		return VM_FAULT_SIGBUS;
-	else if (fault_size > dax_region->align)
+	else if (fault_size > dev_dax->align)
 		return VM_FAULT_FALLBACK;
 
 	/* if we are outside of the VMA */
···
 {
 	unsigned long pud_addr = vmf->address & PUD_MASK;
 	struct device *dev = &dev_dax->dev;
-	struct dax_region *dax_region;
 	phys_addr_t phys;
 	pgoff_t pgoff;
 	unsigned int fault_size = PUD_SIZE;
···
 	if (check_vma(dev_dax, vmf->vma, __func__))
 		return VM_FAULT_SIGBUS;
 
-	dax_region = dev_dax->region;
-	if (dax_region->align > PUD_SIZE) {
+	if (dev_dax->align > PUD_SIZE) {
 		dev_dbg(dev, "alignment (%#x) > fault size (%#x)\n",
-			dax_region->align, fault_size);
+			dev_dax->align, fault_size);
 		return VM_FAULT_SIGBUS;
 	}
 
-	if (fault_size < dax_region->align)
+	if (fault_size < dev_dax->align)
 		return VM_FAULT_SIGBUS;
-	else if (fault_size > dax_region->align)
+	else if (fault_size > dev_dax->align)
 		return VM_FAULT_FALLBACK;
 
 	/* if we are outside of the VMA */
···
 {
 	struct file *filp = vma->vm_file;
 	struct dev_dax *dev_dax = filp->private_data;
-	struct dax_region *dax_region = dev_dax->region;
 
-	if (!IS_ALIGNED(addr, dax_region->align))
+	if (!IS_ALIGNED(addr, dev_dax->align))
 		return -EINVAL;
 	return 0;
 }
···
 {
 	struct file *filp = vma->vm_file;
 	struct dev_dax *dev_dax = filp->private_data;
-	struct dax_region *dax_region = dev_dax->region;
 
-	return dax_region->align;
+	return dev_dax->align;
 }
 
 static const struct vm_operations_struct dax_vm_ops = {
···
 {
 	unsigned long off, off_end, off_align, len_align, addr_align, align;
 	struct dev_dax *dev_dax = filp ? filp->private_data : NULL;
-	struct dax_region *dax_region;
 
 	if (!dev_dax || addr)
 		goto out;
 
-	dax_region = dev_dax->region;
-	align = dax_region->align;
+	align = dev_dax->align;
 	off = pgoff << PAGE_SHIFT;
 	off_end = off + len;
 	off_align = round_up(off, align);