dax: Rename some functions

Remove mentions of 'radix' and 'radix tree'.  Simplify some names by
dropping the word 'mapping'.
Signed-off-by: Matthew Wilcox <willy@infradead.org>

fs/dax.c

@@ -74,18 +74,18 @@ fs_initcall(init_dax_wait_table);
 #define DAX_ZERO_PAGE	(1UL << 2)
 #define DAX_EMPTY	(1UL << 3)
 
-static unsigned long dax_radix_pfn(void *entry)
+static unsigned long dax_to_pfn(void *entry)
 {
 	return xa_to_value(entry) >> DAX_SHIFT;
 }
 
-static void *dax_radix_locked_entry(unsigned long pfn, unsigned long flags)
+static void *dax_make_locked(unsigned long pfn, unsigned long flags)
 {
 	return xa_mk_value(flags | ((unsigned long)pfn << DAX_SHIFT) |
 			DAX_LOCKED);
 }
 
-static unsigned int dax_radix_order(void *entry)
+static unsigned int dax_entry_order(void *entry)
 {
 	if (xa_to_value(entry) & DAX_PMD)
 		return PMD_SHIFT - PAGE_SHIFT;
@@ -113,7 +113,7 @@ static int dax_is_empty_entry(void *entry)
 }
 
 /*
- * DAX radix tree locking
+ * DAX page cache entry locking
  */
 struct exceptional_entry_key {
 	struct address_space *mapping;
@@ -217,7 +217,7 @@ static inline void *unlock_slot(struct address_space *mapping, void **slot)
 }
 
 /*
- * Lookup entry in radix tree, wait for it to become unlocked if it is
+ * Lookup entry in page cache, wait for it to become unlocked if it is
  * a DAX entry and return it. The caller must call
  * put_unlocked_mapping_entry() when he decided not to lock the entry or
  * put_locked_mapping_entry() when he locked the entry and now wants to
@@ -299,7 +299,7 @@ static void put_locked_mapping_entry(struct address_space *mapping,
 }
 
 /*
- * Called when we are done with radix tree entry we looked up via
+ * Called when we are done with page cache entry we looked up via
  * get_unlocked_mapping_entry() and which we didn't lock in the end.
  */
 static void put_unlocked_mapping_entry(struct address_space *mapping,
@@ -308,7 +308,7 @@ static void put_unlocked_mapping_entry(struct address_space *mapping,
 	if (!entry)
 		return;
 
-	/* We have to wake up next waiter for the radix tree entry lock */
+	/* We have to wake up next waiter for the page cache entry lock */
 	dax_wake_mapping_entry_waiter(mapping, index, entry, false);
 }
 
@@ -324,9 +324,9 @@ static unsigned long dax_entry_size(void *entry)
 		return PAGE_SIZE;
 }
 
-static unsigned long dax_radix_end_pfn(void *entry)
+static unsigned long dax_end_pfn(void *entry)
 {
-	return dax_radix_pfn(entry) + dax_entry_size(entry) / PAGE_SIZE;
+	return dax_to_pfn(entry) + dax_entry_size(entry) / PAGE_SIZE;
 }
 
 /*
@@ -334,8 +334,8 @@ static unsigned long dax_radix_end_pfn(void *entry)
  * 'empty' and 'zero' entries.
  */
 #define for_each_mapped_pfn(entry, pfn) \
-	for (pfn = dax_radix_pfn(entry); \
-			pfn < dax_radix_end_pfn(entry); pfn++)
+	for (pfn = dax_to_pfn(entry); \
+			pfn < dax_end_pfn(entry); pfn++)
 
 /*
  * TODO: for reflink+dax we need a way to associate a single page with
@@ -471,9 +471,9 @@ void dax_unlock_mapping_entry(struct page *page)
 }
 
 /*
- * Find radix tree entry at given index. If it is a DAX entry, return it
- * with the radix tree entry locked. If the radix tree doesn't contain the
- * given index, create an empty entry for the index and return with it locked.
+ * Find page cache entry at given index. If it is a DAX entry, return it
+ * with the entry locked. If the page cache doesn't contain an entry at
+ * that index, add a locked empty entry.
  *
  * When requesting an entry with size DAX_PMD, grab_mapping_entry() will
  * either return that locked entry or will return an error.  This error will
@@ -582,10 +582,10 @@ static void *grab_mapping_entry(struct address_space *mapping, pgoff_t index,
 					true);
 		}
 
-		entry = dax_radix_locked_entry(0, size_flag | DAX_EMPTY);
+		entry = dax_make_locked(0, size_flag | DAX_EMPTY);
 
 		err = __radix_tree_insert(&mapping->i_pages, index,
-				dax_radix_order(entry), entry);
+				dax_entry_order(entry), entry);
 		radix_tree_preload_end();
 		if (err) {
 			xa_unlock_irq(&mapping->i_pages);
@@ -701,7 +701,7 @@ struct page *dax_layout_busy_page(struct address_space *mapping)
 }
 EXPORT_SYMBOL_GPL(dax_layout_busy_page);
 
-static int __dax_invalidate_mapping_entry(struct address_space *mapping,
+static int __dax_invalidate_entry(struct address_space *mapping,
 					  pgoff_t index, bool trunc)
 {
 	int ret = 0;
@@ -731,12 +731,12 @@ static int __dax_invalidate_mapping_entry(struct address_space *mapping,
  */
 int dax_delete_mapping_entry(struct address_space *mapping, pgoff_t index)
 {
-	int ret = __dax_invalidate_mapping_entry(mapping, index, true);
+	int ret = __dax_invalidate_entry(mapping, index, true);
 
 	/*
 	 * This gets called from truncate / punch_hole path. As such, the caller
 	 * must hold locks protecting against concurrent modifications of the
-	 * radix tree (usually fs-private i_mmap_sem for writing). Since the
+	 * page cache (usually fs-private i_mmap_sem for writing). Since the
 	 * caller has seen a DAX entry for this index, we better find it
 	 * at that index as well...
 	 */
@@ -750,7 +750,7 @@ int dax_delete_mapping_entry(struct address_space *mapping, pgoff_t index)
 int dax_invalidate_mapping_entry_sync(struct address_space *mapping,
 				      pgoff_t index)
 {
-	return __dax_invalidate_mapping_entry(mapping, index, false);
+	return __dax_invalidate_entry(mapping, index, false);
 }
 
 static int copy_user_dax(struct block_device *bdev, struct dax_device *dax_dev,
@@ -786,10 +786,9 @@ static int copy_user_dax(struct block_device *bdev, struct dax_device *dax_dev,
  * already in the tree, we will skip the insertion and just dirty the PMD as
  * appropriate.
  */
-static void *dax_insert_mapping_entry(struct address_space *mapping,
-				      struct vm_fault *vmf,
-				      void *entry, pfn_t pfn_t,
-				      unsigned long flags, bool dirty)
+static void *dax_insert_entry(struct address_space *mapping,
+		struct vm_fault *vmf,
+		void *entry, pfn_t pfn_t, unsigned long flags, bool dirty)
 {
 	struct radix_tree_root *pages = &mapping->i_pages;
 	unsigned long pfn = pfn_t_to_pfn(pfn_t);
@@ -809,7 +808,7 @@ static void *dax_insert_mapping_entry(struct address_space *mapping,
 	}
 
 	xa_lock_irq(pages);
-	new_entry = dax_radix_locked_entry(pfn, flags);
+	new_entry = dax_make_locked(pfn, flags);
 	if (dax_entry_size(entry) != dax_entry_size(new_entry)) {
 		dax_disassociate_entry(entry, mapping, false);
 		dax_associate_entry(new_entry, mapping, vmf->vma, vmf->address);
@@ -817,9 +816,9 @@ static void *dax_insert_mapping_entry(struct address_space *mapping,
 
 	if (dax_is_zero_entry(entry) || dax_is_empty_entry(entry)) {
 		/*
-		 * Only swap our new entry into the radix tree if the current
+		 * Only swap our new entry into the page cache if the current
 		 * entry is a zero page or an empty entry.  If a normal PTE or
-		 * PMD entry is already in the tree, we leave it alone.  This
+		 * PMD entry is already in the cache, we leave it alone.  This
 		 * means that if we are trying to insert a PTE and the
 		 * existing entry is a PMD, we will just leave the PMD in the
 		 * tree and dirty it if necessary.
@@ -842,8 +841,8 @@ static void *dax_insert_mapping_entry(struct address_space *mapping,
 	return entry;
 }
 
-static inline unsigned long
-pgoff_address(pgoff_t pgoff, struct vm_area_struct *vma)
+static inline
+unsigned long pgoff_address(pgoff_t pgoff, struct vm_area_struct *vma)
 {
 	unsigned long address;
 
@@ -853,8 +852,8 @@ pgoff_address(pgoff_t pgoff, struct vm_area_struct *vma)
 }
 
 /* Walk all mappings of a given index of a file and writeprotect them */
-static void dax_mapping_entry_mkclean(struct address_space *mapping,
-				      pgoff_t index, unsigned long pfn)
+static void dax_entry_mkclean(struct address_space *mapping, pgoff_t index,
+		unsigned long pfn)
 {
 	struct vm_area_struct *vma;
 	pte_t pte, *ptep = NULL;
@@ -950,7 +949,7 @@ static int dax_writeback_one(struct dax_device *dax_dev,
 	 * compare pfns as we must not bail out due to difference in lockbit
 	 * or entry type.
 	 */
-	if (dax_radix_pfn(entry2) != dax_radix_pfn(entry))
+	if (dax_to_pfn(entry2) != dax_to_pfn(entry))
 		goto put_unlocked;
 	if (WARN_ON_ONCE(dax_is_empty_entry(entry) ||
 				dax_is_zero_entry(entry))) {
@@ -980,10 +979,10 @@ static int dax_writeback_one(struct dax_device *dax_dev,
 	 * This allows us to flush for PMD_SIZE and not have to worry about
 	 * partial PMD writebacks.
 	 */
-	pfn = dax_radix_pfn(entry);
-	size = PAGE_SIZE << dax_radix_order(entry);
+	pfn = dax_to_pfn(entry);
+	size = PAGE_SIZE << dax_entry_order(entry);
 
-	dax_mapping_entry_mkclean(mapping, index, pfn);
+	dax_entry_mkclean(mapping, index, pfn);
 	dax_flush(dax_dev, page_address(pfn_to_page(pfn)), size);
 	/*
 	 * After we have flushed the cache, we can clear the dirty tag. There
@@ -1120,7 +1119,7 @@ static vm_fault_t dax_load_hole(struct address_space *mapping, void *entry,
 	pfn_t pfn = pfn_to_pfn_t(my_zero_pfn(vaddr));
 	vm_fault_t ret;
 
-	dax_insert_mapping_entry(mapping, vmf, entry, pfn,
+	dax_insert_entry(mapping, vmf, entry, pfn,
 			DAX_ZERO_PAGE, false);
 
 	ret = vmf_insert_mixed(vmf->vma, vaddr, pfn);
@@ -1431,7 +1430,7 @@ static vm_fault_t dax_iomap_pte_fault(struct vm_fault *vmf, pfn_t *pfnp,
 		if (error < 0)
 			goto error_finish_iomap;
 
-		entry = dax_insert_mapping_entry(mapping, vmf, entry, pfn,
+		entry = dax_insert_entry(mapping, vmf, entry, pfn,
 						 0, write && !sync);
 
 		/*
@@ -1511,7 +1510,7 @@ static vm_fault_t dax_pmd_load_hole(struct vm_fault *vmf, struct iomap *iomap,
 		goto fallback;
 
 	pfn = page_to_pfn_t(zero_page);
-	ret = dax_insert_mapping_entry(mapping, vmf, entry, pfn,
+	ret = dax_insert_entry(mapping, vmf, entry, pfn,
 			DAX_PMD | DAX_ZERO_PAGE, false);
 
 	ptl = pmd_lock(vmf->vma->vm_mm, vmf->pmd);
@@ -1564,7 +1563,7 @@ static vm_fault_t dax_iomap_pmd_fault(struct vm_fault *vmf, pfn_t *pfnp,
 	 * Make sure that the faulting address's PMD offset (color) matches
 	 * the PMD offset from the start of the file.  This is necessary so
 	 * that a PMD range in the page table overlaps exactly with a PMD
-	 * range in the radix tree.
+	 * range in the page cache.
 	 */
 	if ((vmf->pgoff & PG_PMD_COLOUR) !=
 	    ((vmf->address >> PAGE_SHIFT) & PG_PMD_COLOUR))
@@ -1632,7 +1631,7 @@ static vm_fault_t dax_iomap_pmd_fault(struct vm_fault *vmf, pfn_t *pfnp,
 		if (error < 0)
 			goto finish_iomap;
 
-		entry = dax_insert_mapping_entry(mapping, vmf, entry, pfn,
+		entry = dax_insert_entry(mapping, vmf, entry, pfn,
 						DAX_PMD, write && !sync);
 
 		/*
@@ -1725,15 +1724,14 @@ vm_fault_t dax_iomap_fault(struct vm_fault *vmf, enum page_entry_size pe_size,
 }
 EXPORT_SYMBOL_GPL(dax_iomap_fault);
 
-/**
+/*
  * dax_insert_pfn_mkwrite - insert PTE or PMD entry into page tables
  * @vmf: The description of the fault
  * @pe_size: Size of entry to be inserted
  * @pfn: PFN to insert
  *
- * This function inserts writeable PTE or PMD entry into page tables for mmaped
- * DAX file.  It takes care of marking corresponding radix tree entry as dirty
- * as well.
+ * This function inserts a writeable PTE or PMD entry into the page tables
+ * for an mmaped DAX file.  It also marks the page cache entry as dirty.
  */
 static vm_fault_t dax_insert_pfn_mkwrite(struct vm_fault *vmf,
 				  enum page_entry_size pe_size,