Merge branch 'for-5.9/dax' into libnvdimm-for-next

This contains a handful of dax changes for v5.9. Of the three commits,
one is a print verbosity change, and two are independent fixes that fell
out of the PKS work [1].

[1]: https://lore.kernel.org/linux-nvdimm/20200717072056.73134-1-ira.weiny@intel.com

drivers/dax/super.c

@@ -80,14 +80,14 @@ bool __generic_fsdax_supported(struct dax_device *dax_dev,
 	int err, id;
 
 	if (blocksize != PAGE_SIZE) {
-		pr_debug("%s: error: unsupported blocksize for dax\n",
+		pr_info("%s: error: unsupported blocksize for dax\n",
 				bdevname(bdev, buf));
 		return false;
 	}
 
 	err = bdev_dax_pgoff(bdev, start, PAGE_SIZE, &pgoff);
 	if (err) {
-		pr_debug("%s: error: unaligned partition for dax\n",
+		pr_info("%s: error: unaligned partition for dax\n",
 				bdevname(bdev, buf));
 		return false;
 	}
@@ -95,7 +95,7 @@ bool __generic_fsdax_supported(struct dax_device *dax_dev,
 	last_page = PFN_DOWN((start + sectors - 1) * 512) * PAGE_SIZE / 512;
 	err = bdev_dax_pgoff(bdev, last_page, PAGE_SIZE, &pgoff_end);
 	if (err) {
-		pr_debug("%s: error: unaligned partition for dax\n",
+		pr_info("%s: error: unaligned partition for dax\n",
 				bdevname(bdev, buf));
 		return false;
 	}
@@ -103,11 +103,11 @@ bool __generic_fsdax_supported(struct dax_device *dax_dev,
 	id = dax_read_lock();
 	len = dax_direct_access(dax_dev, pgoff, 1, &kaddr, &pfn);
 	len2 = dax_direct_access(dax_dev, pgoff_end, 1, &end_kaddr, &end_pfn);
-	dax_read_unlock(id);
 
 	if (len < 1 || len2 < 1) {
-		pr_debug("%s: error: dax access failed (%ld)\n",
+		pr_info("%s: error: dax access failed (%ld)\n",
 				bdevname(bdev, buf), len < 1 ? len : len2);
+		dax_read_unlock(id);
 		return false;
 	}
 
@@ -137,9 +137,10 @@ bool __generic_fsdax_supported(struct dax_device *dax_dev,
 		put_dev_pagemap(end_pgmap);
 
 	}
+	dax_read_unlock(id);
 
 	if (!dax_enabled) {
-		pr_debug("%s: error: dax support not enabled\n",
+		pr_info("%s: error: dax support not enabled\n",
 				bdevname(bdev, buf));
 		return false;
 	}

fs/dax.c

@@ -680,21 +680,20 @@ int dax_invalidate_mapping_entry_sync(struct address_space *mapping,
 	return __dax_invalidate_entry(mapping, index, false);
 }
 
-static int copy_user_dax(struct block_device *bdev, struct dax_device *dax_dev,
-		sector_t sector, size_t size, struct page *to,
-		unsigned long vaddr)
+static int copy_cow_page_dax(struct block_device *bdev, struct dax_device *dax_dev,
+			     sector_t sector, struct page *to, unsigned long vaddr)
 {
 	void *vto, *kaddr;
 	pgoff_t pgoff;
 	long rc;
 	int id;
 
-	rc = bdev_dax_pgoff(bdev, sector, size, &pgoff);
+	rc = bdev_dax_pgoff(bdev, sector, PAGE_SIZE, &pgoff);
 	if (rc)
 		return rc;
 
 	id = dax_read_lock();
-	rc = dax_direct_access(dax_dev, pgoff, PHYS_PFN(size), &kaddr, NULL);
+	rc = dax_direct_access(dax_dev, pgoff, PHYS_PFN(PAGE_SIZE), &kaddr, NULL);
 	if (rc < 0) {
 		dax_read_unlock(id);
 		return rc;
@@ -1305,8 +1304,8 @@ static vm_fault_t dax_iomap_pte_fault(struct vm_fault *vmf, pfn_t *pfnp,
 			clear_user_highpage(vmf->cow_page, vaddr);
 			break;
 		case IOMAP_MAPPED:
-			error = copy_user_dax(iomap.bdev, iomap.dax_dev,
-					sector, PAGE_SIZE, vmf->cow_page, vaddr);
+			error = copy_cow_page_dax(iomap.bdev, iomap.dax_dev,
+						  sector, vmf->cow_page, vaddr);
 			break;
 		default:
 			WARN_ON_ONCE(1);