[Spice-devel] [patch 7/7] io-mapping: Remove io_mapping_map_atomic_wc()

[Thomas Gleixner]

From: Thomas Gleixner <tglx at linutronix.de>

No more users. Get rid of it and remove the traces in documentation.

Signed-off-by: Thomas Gleixner <tglx at linutronix.de>
Cc: Andrew Morton <akpm at linux-foundation.org>
Cc: linux-mm at kvack.org
---
 Documentation/driver-api/io-mapping.rst |   22 +++++-----------
 include/linux/io-mapping.h              |   42 +-------------------------------
 2 files changed, 9 insertions(+), 55 deletions(-)

--- a/Documentation/driver-api/io-mapping.rst
+++ b/Documentation/driver-api/io-mapping.rst
@@ -21,19 +21,15 @@ mappable, while 'size' indicates how lar
 enable. Both are in bytes.
 
 This _wc variant provides a mapping which may only be used with
-io_mapping_map_atomic_wc(), io_mapping_map_local_wc() or
-io_mapping_map_wc().
+io_mapping_map_local_wc() or io_mapping_map_wc().
 
 With this mapping object, individual pages can be mapped either temporarily
 or long term, depending on the requirements. Of course, temporary maps are
-more efficient. They come in two flavours::
+more efficient.
 
 	void *io_mapping_map_local_wc(struct io_mapping *mapping,
 				      unsigned long offset)
 
-	void *io_mapping_map_atomic_wc(struct io_mapping *mapping,
-				       unsigned long offset)
-
 'offset' is the offset within the defined mapping region.  Accessing
 addresses beyond the region specified in the creation function yields
 undefined results. Using an offset which is not page aligned yields an
@@ -50,9 +46,6 @@ io_mapping_map_local_wc() has a side eff
 migration to make the mapping code work. No caller can rely on this side
 effect.
 
-io_mapping_map_atomic_wc() has the side effect of disabling preemption and
-pagefaults. Don't use in new code. Use io_mapping_map_local_wc() instead.
-
 Nested mappings need to be undone in reverse order because the mapping
 code uses a stack for keeping track of them::
 
@@ -65,11 +58,10 @@ Nested mappings need to be undone in rev
 The mappings are released with::
 
 	void io_mapping_unmap_local(void *vaddr)
-	void io_mapping_unmap_atomic(void *vaddr)
 
-'vaddr' must be the value returned by the last io_mapping_map_local_wc() or
-io_mapping_map_atomic_wc() call. This unmaps the specified mapping and
-undoes the side effects of the mapping functions.
+'vaddr' must be the value returned by the last io_mapping_map_local_wc()
+call. This unmaps the specified mapping and undoes eventual side effects of
+the mapping function.
 
 If you need to sleep while holding a mapping, you can use the regular
 variant, although this may be significantly slower::
@@ -77,8 +69,8 @@ If you need to sleep while holding a map
 	void *io_mapping_map_wc(struct io_mapping *mapping,
 				unsigned long offset)
 
-This works like io_mapping_map_atomic/local_wc() except it has no side
-effects and the pointer is globaly visible.
+This works like io_mapping_map_local_wc() except it has no side effects and
+the pointer is globaly visible.
 
 The mappings are released with::
 
--- a/include/linux/io-mapping.h
+++ b/include/linux/io-mapping.h
@@ -60,28 +60,7 @@ io_mapping_fini(struct io_mapping *mappi
 	iomap_free(mapping->base, mapping->size);
 }
 
-/* Atomic map/unmap */
-static inline void __iomem *
-io_mapping_map_atomic_wc(struct io_mapping *mapping,
-			 unsigned long offset)
-{
-	resource_size_t phys_addr;
-
-	BUG_ON(offset >= mapping->size);
-	phys_addr = mapping->base + offset;
-	preempt_disable();
-	pagefault_disable();
-	return __iomap_local_pfn_prot(PHYS_PFN(phys_addr), mapping->prot);
-}
-
-static inline void
-io_mapping_unmap_atomic(void __iomem *vaddr)
-{
-	kunmap_local_indexed((void __force *)vaddr);
-	pagefault_enable();
-	preempt_enable();
-}
-
+/* Temporary mappings which are only valid in the current context */
 static inline void __iomem *
 io_mapping_map_local_wc(struct io_mapping *mapping, unsigned long offset)
 {
@@ -163,24 +142,7 @@ io_mapping_unmap(void __iomem *vaddr)
 {
 }
 
-/* Atomic map/unmap */
-static inline void __iomem *
-io_mapping_map_atomic_wc(struct io_mapping *mapping,
-			 unsigned long offset)
-{
-	preempt_disable();
-	pagefault_disable();
-	return io_mapping_map_wc(mapping, offset, PAGE_SIZE);
-}
-
-static inline void
-io_mapping_unmap_atomic(void __iomem *vaddr)
-{
-	io_mapping_unmap(vaddr);
-	pagefault_enable();
-	preempt_enable();
-}
-
+/* Temporary mappings which are only valid in the current context */
 static inline void __iomem *
 io_mapping_map_local_wc(struct io_mapping *mapping, unsigned long offset)
 {