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-rw-r--r--arch/powerpc/sysdev/axonram.c9
-rw-r--r--drivers/block/brd.c7
-rw-r--r--drivers/nvdimm/pmem.c13
-rw-r--r--drivers/s390/block/dcssblk.c11
-rw-r--r--fs/dax.c11
-rw-r--r--include/linux/blkdev.h5
-rw-r--r--include/linux/pfn.h9
-rw-r--r--include/linux/pfn_t.h67
-rw-r--r--kernel/memremap.c7
9 files changed, 116 insertions, 23 deletions
diff --git a/arch/powerpc/sysdev/axonram.c b/arch/powerpc/sysdev/axonram.c
index c713b349d967..0d112b94d91d 100644
--- a/arch/powerpc/sysdev/axonram.c
+++ b/arch/powerpc/sysdev/axonram.c
@@ -43,6 +43,7 @@
 #include <linux/types.h>
 #include <linux/of_device.h>
 #include <linux/of_platform.h>
+#include <linux/pfn_t.h>
 
 #include <asm/page.h>
 #include <asm/prom.h>
@@ -142,15 +143,13 @@ axon_ram_make_request(struct request_queue *queue, struct bio *bio)
  */
 static long
 axon_ram_direct_access(struct block_device *device, sector_t sector,
-		       void __pmem **kaddr, unsigned long *pfn)
+		       void __pmem **kaddr, pfn_t *pfn)
 {
 	struct axon_ram_bank *bank = device->bd_disk->private_data;
 	loff_t offset = (loff_t)sector << AXON_RAM_SECTOR_SHIFT;
-	void *addr = (void *)(bank->ph_addr + offset);
-
-	*kaddr = (void __pmem *)addr;
-	*pfn = virt_to_phys(addr) >> PAGE_SHIFT;
 
+	*kaddr = (void __pmem __force *) bank->io_addr + offset;
+	*pfn = phys_to_pfn_t(bank->ph_addr + offset, PFN_DEV);
 	return bank->size - offset;
 }
 
diff --git a/drivers/block/brd.c b/drivers/block/brd.c
index a5880f4ab40e..cb27190e9f39 100644
--- a/drivers/block/brd.c
+++ b/drivers/block/brd.c
@@ -19,6 +19,9 @@
 #include <linux/radix-tree.h>
 #include <linux/fs.h>
 #include <linux/slab.h>
+#ifdef CONFIG_BLK_DEV_RAM_DAX
+#include <linux/pfn_t.h>
+#endif
 
 #include <asm/uaccess.h>
 
@@ -378,7 +381,7 @@ static int brd_rw_page(struct block_device *bdev, sector_t sector,
 
 #ifdef CONFIG_BLK_DEV_RAM_DAX
 static long brd_direct_access(struct block_device *bdev, sector_t sector,
-			void __pmem **kaddr, unsigned long *pfn)
+			void __pmem **kaddr, pfn_t *pfn)
 {
 	struct brd_device *brd = bdev->bd_disk->private_data;
 	struct page *page;
@@ -389,7 +392,7 @@ static long brd_direct_access(struct block_device *bdev, sector_t sector,
 	if (!page)
 		return -ENOSPC;
 	*kaddr = (void __pmem *)page_address(page);
-	*pfn = page_to_pfn(page);
+	*pfn = page_to_pfn_t(page);
 
 	return PAGE_SIZE;
 }
diff --git a/drivers/nvdimm/pmem.c b/drivers/nvdimm/pmem.c
index b493ff3fccb2..5def7f4ddbd2 100644
--- a/drivers/nvdimm/pmem.c
+++ b/drivers/nvdimm/pmem.c
@@ -25,6 +25,7 @@
 #include <linux/moduleparam.h>
 #include <linux/badblocks.h>
 #include <linux/vmalloc.h>
+#include <linux/pfn_t.h>
 #include <linux/slab.h>
 #include <linux/pmem.h>
 #include <linux/nd.h>
@@ -40,6 +41,7 @@ struct pmem_device {
 	phys_addr_t		phys_addr;
 	/* when non-zero this device is hosting a 'pfn' instance */
 	phys_addr_t		data_offset;
+	unsigned long		pfn_flags;
 	void __pmem		*virt_addr;
 	size_t			size;
 	struct badblocks	bb;
@@ -135,13 +137,13 @@ static int pmem_rw_page(struct block_device *bdev, sector_t sector,
 }
 
 static long pmem_direct_access(struct block_device *bdev, sector_t sector,
-		      void __pmem **kaddr, unsigned long *pfn)
+		      void __pmem **kaddr, pfn_t *pfn)
 {
 	struct pmem_device *pmem = bdev->bd_disk->private_data;
 	resource_size_t offset = sector * 512 + pmem->data_offset;
 
 	*kaddr = pmem->virt_addr + offset;
-	*pfn = (pmem->phys_addr + offset) >> PAGE_SHIFT;
+	*pfn = phys_to_pfn_t(pmem->phys_addr + offset, pmem->pfn_flags);
 
 	return pmem->size - offset;
 }
@@ -174,9 +176,11 @@ static struct pmem_device *pmem_alloc(struct device *dev,
 		return ERR_PTR(-EBUSY);
 	}
 
-	if (pmem_should_map_pages(dev))
+	pmem->pfn_flags = PFN_DEV;
+	if (pmem_should_map_pages(dev)) {
 		pmem->virt_addr = (void __pmem *) devm_memremap_pages(dev, res);
-	else
+		pmem->pfn_flags |= PFN_MAP;
+	} else
 		pmem->virt_addr = (void __pmem *) devm_memremap(dev,
 				pmem->phys_addr, pmem->size,
 				ARCH_MEMREMAP_PMEM);
@@ -384,6 +388,7 @@ static int nvdimm_namespace_attach_pfn(struct nd_namespace_common *ndns)
 	pmem = dev_get_drvdata(dev);
 	devm_memunmap(dev, (void __force *) pmem->virt_addr);
 	pmem->virt_addr = (void __pmem *) devm_memremap_pages(dev, &nsio->res);
+	pmem->pfn_flags |= PFN_MAP;
 	if (IS_ERR(pmem->virt_addr)) {
 		rc = PTR_ERR(pmem->virt_addr);
 		goto err;
diff --git a/drivers/s390/block/dcssblk.c b/drivers/s390/block/dcssblk.c
index 94a8f4ab57bc..ce7b70181740 100644
--- a/drivers/s390/block/dcssblk.c
+++ b/drivers/s390/block/dcssblk.c
@@ -17,6 +17,7 @@
 #include <linux/completion.h>
 #include <linux/interrupt.h>
 #include <linux/platform_device.h>
+#include <linux/pfn_t.h>
 #include <asm/extmem.h>
 #include <asm/io.h>
 
@@ -30,7 +31,7 @@ static void dcssblk_release(struct gendisk *disk, fmode_t mode);
 static blk_qc_t dcssblk_make_request(struct request_queue *q,
 						struct bio *bio);
 static long dcssblk_direct_access(struct block_device *bdev, sector_t secnum,
-			 void __pmem **kaddr, unsigned long *pfn);
+			 void __pmem **kaddr, pfn_t *pfn);
 
 static char dcssblk_segments[DCSSBLK_PARM_LEN] = "\0";
 
@@ -883,20 +884,18 @@ fail:
 
 static long
 dcssblk_direct_access (struct block_device *bdev, sector_t secnum,
-			void __pmem **kaddr, unsigned long *pfn)
+			void __pmem **kaddr, pfn_t *pfn)
 {
 	struct dcssblk_dev_info *dev_info;
 	unsigned long offset, dev_sz;
-	void *addr;
 
 	dev_info = bdev->bd_disk->private_data;
 	if (!dev_info)
 		return -ENODEV;
 	dev_sz = dev_info->end - dev_info->start;
 	offset = secnum * 512;
-	addr = (void *) (dev_info->start + offset);
-	*pfn = virt_to_phys(addr) >> PAGE_SHIFT;
-	*kaddr = (void __pmem *) addr;
+	*kaddr = (void __pmem *) (dev_info->start + offset);
+	*pfn = __pfn_to_pfn_t(PFN_DOWN(dev_info->start + offset), PFN_DEV);
 
 	return dev_sz - offset;
 }
diff --git a/fs/dax.c b/fs/dax.c
index 3220da70ee20..6b13d6cd9a9a 100644
--- a/fs/dax.c
+++ b/fs/dax.c
@@ -28,6 +28,7 @@
 #include <linux/sched.h>
 #include <linux/uio.h>
 #include <linux/vmstat.h>
+#include <linux/pfn_t.h>
 #include <linux/sizes.h>
 
 static long dax_map_atomic(struct block_device *bdev, struct blk_dax_ctl *dax)
@@ -362,7 +363,7 @@ static int dax_insert_mapping(struct inode *inode, struct buffer_head *bh,
 	}
 	dax_unmap_atomic(bdev, &dax);
 
-	error = vm_insert_mixed(vma, vaddr, dax.pfn);
+	error = vm_insert_mixed(vma, vaddr, pfn_t_to_pfn(dax.pfn));
 
  out:
 	i_mmap_unlock_read(mapping);
@@ -667,7 +668,8 @@ int __dax_pmd_fault(struct vm_area_struct *vma, unsigned long address,
 			result = VM_FAULT_SIGBUS;
 			goto out;
 		}
-		if ((length < PMD_SIZE) || (dax.pfn & PG_PMD_COLOUR)) {
+		if (length < PMD_SIZE
+				|| (pfn_t_to_pfn(dax.pfn) & PG_PMD_COLOUR)) {
 			dax_unmap_atomic(bdev, &dax);
 			goto fallback;
 		}
@@ -676,7 +678,7 @@ int __dax_pmd_fault(struct vm_area_struct *vma, unsigned long address,
 		 * TODO: teach vmf_insert_pfn_pmd() to support
 		 * 'pte_special' for pmds
 		 */
-		if (pfn_valid(dax.pfn)) {
+		if (pfn_t_has_page(dax.pfn)) {
 			dax_unmap_atomic(bdev, &dax);
 			goto fallback;
 		}
@@ -690,7 +692,8 @@ int __dax_pmd_fault(struct vm_area_struct *vma, unsigned long address,
 		}
 		dax_unmap_atomic(bdev, &dax);
 
-		result |= vmf_insert_pfn_pmd(vma, address, pmd, dax.pfn, write);
+		result |= vmf_insert_pfn_pmd(vma, address, pmd,
+				pfn_t_to_pfn(dax.pfn), write);
 	}
 
  out:
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 88821fa26f19..bfb64d672e19 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -15,6 +15,7 @@
 #include <linux/backing-dev-defs.h>
 #include <linux/wait.h>
 #include <linux/mempool.h>
+#include <linux/pfn.h>
 #include <linux/bio.h>
 #include <linux/stringify.h>
 #include <linux/gfp.h>
@@ -1628,7 +1629,7 @@ struct blk_dax_ctl {
 	sector_t sector;
 	void __pmem *addr;
 	long size;
-	unsigned long pfn;
+	pfn_t pfn;
 };
 
 struct block_device_operations {
@@ -1638,7 +1639,7 @@ struct block_device_operations {
 	int (*ioctl) (struct block_device *, fmode_t, unsigned, unsigned long);
 	int (*compat_ioctl) (struct block_device *, fmode_t, unsigned, unsigned long);
 	long (*direct_access)(struct block_device *, sector_t, void __pmem **,
-			unsigned long *pfn);
+			pfn_t *);
 	unsigned int (*check_events) (struct gendisk *disk,
 				      unsigned int clearing);
 	/* ->media_changed() is DEPRECATED, use ->check_events() instead */
diff --git a/include/linux/pfn.h b/include/linux/pfn.h
index 97f3e88aead4..2d8e49711b63 100644
--- a/include/linux/pfn.h
+++ b/include/linux/pfn.h
@@ -3,6 +3,15 @@
 
 #ifndef __ASSEMBLY__
 #include <linux/types.h>
+
+/*
+ * pfn_t: encapsulates a page-frame number that is optionally backed
+ * by memmap (struct page).  Whether a pfn_t has a 'struct page'
+ * backing is indicated by flags in the high bits of the value.
+ */
+typedef struct {
+	unsigned long val;
+} pfn_t;
 #endif
 
 #define PFN_ALIGN(x)	(((unsigned long)(x) + (PAGE_SIZE - 1)) & PAGE_MASK)
diff --git a/include/linux/pfn_t.h b/include/linux/pfn_t.h
new file mode 100644
index 000000000000..c557a0e0b20c
--- /dev/null
+++ b/include/linux/pfn_t.h
@@ -0,0 +1,67 @@
+#ifndef _LINUX_PFN_T_H_
+#define _LINUX_PFN_T_H_
+#include <linux/mm.h>
+
+/*
+ * PFN_FLAGS_MASK - mask of all the possible valid pfn_t flags
+ * PFN_SG_CHAIN - pfn is a pointer to the next scatterlist entry
+ * PFN_SG_LAST - pfn references a page and is the last scatterlist entry
+ * PFN_DEV - pfn is not covered by system memmap by default
+ * PFN_MAP - pfn has a dynamic page mapping established by a device driver
+ */
+#define PFN_FLAGS_MASK (((unsigned long) ~PAGE_MASK) \
+		<< (BITS_PER_LONG - PAGE_SHIFT))
+#define PFN_SG_CHAIN (1UL << (BITS_PER_LONG - 1))
+#define PFN_SG_LAST (1UL << (BITS_PER_LONG - 2))
+#define PFN_DEV (1UL << (BITS_PER_LONG - 3))
+#define PFN_MAP (1UL << (BITS_PER_LONG - 4))
+
+static inline pfn_t __pfn_to_pfn_t(unsigned long pfn, unsigned long flags)
+{
+	pfn_t pfn_t = { .val = pfn | (flags & PFN_FLAGS_MASK), };
+
+	return pfn_t;
+}
+
+/* a default pfn to pfn_t conversion assumes that @pfn is pfn_valid() */
+static inline pfn_t pfn_to_pfn_t(unsigned long pfn)
+{
+	return __pfn_to_pfn_t(pfn, 0);
+}
+
+extern pfn_t phys_to_pfn_t(dma_addr_t addr, unsigned long flags);
+
+static inline bool pfn_t_has_page(pfn_t pfn)
+{
+	return (pfn.val & PFN_MAP) == PFN_MAP || (pfn.val & PFN_DEV) == 0;
+}
+
+static inline unsigned long pfn_t_to_pfn(pfn_t pfn)
+{
+	return pfn.val & ~PFN_FLAGS_MASK;
+}
+
+static inline struct page *pfn_t_to_page(pfn_t pfn)
+{
+	if (pfn_t_has_page(pfn))
+		return pfn_to_page(pfn_t_to_pfn(pfn));
+	return NULL;
+}
+
+static inline dma_addr_t pfn_t_to_phys(pfn_t pfn)
+{
+	return PFN_PHYS(pfn_t_to_pfn(pfn));
+}
+
+static inline void *pfn_t_to_virt(pfn_t pfn)
+{
+	if (pfn_t_has_page(pfn))
+		return __va(pfn_t_to_phys(pfn));
+	return NULL;
+}
+
+static inline pfn_t page_to_pfn_t(struct page *page)
+{
+	return pfn_to_pfn_t(page_to_pfn(page));
+}
+#endif /* _LINUX_PFN_T_H_ */
diff --git a/kernel/memremap.c b/kernel/memremap.c
index 7658d32c5c78..449cb6a5d9a1 100644
--- a/kernel/memremap.c
+++ b/kernel/memremap.c
@@ -12,6 +12,7 @@
  */
 #include <linux/device.h>
 #include <linux/types.h>
+#include <linux/pfn_t.h>
 #include <linux/io.h>
 #include <linux/mm.h>
 #include <linux/memory_hotplug.h>
@@ -147,6 +148,12 @@ void devm_memunmap(struct device *dev, void *addr)
 }
 EXPORT_SYMBOL(devm_memunmap);
 
+pfn_t phys_to_pfn_t(dma_addr_t addr, unsigned long flags)
+{
+	return __pfn_to_pfn_t(addr >> PAGE_SHIFT, flags);
+}
+EXPORT_SYMBOL(phys_to_pfn_t);
+
 #ifdef CONFIG_ZONE_DEVICE
 struct page_map {
 	struct resource res;
generated by cgit-pink 1.4.1 (git 2.36.1) at 2024-09-28 01:22:08 +0000