arch/*/: remove CONFIG_VIRT_TO_BUS

All architecture-independent users of virt_to_bus() and bus_to_virt()
have been fixed to use the dma mapping interfaces or have been
removed now.  This means the definitions on most architectures, and the
CONFIG_VIRT_TO_BUS symbol are now obsolete and can be removed.

The only exceptions to this are a few network and scsi drivers for m68k
Amiga and VME machines and ppc32 Macintosh. These drivers work correctly
with the old interfaces and are probably not worth changing.

On alpha and parisc, virt_to_bus() were still used in asm/floppy.h.
alpha can use isa_virt_to_bus() like x86 does, and parisc can just
open-code the virt_to_phys() here, as this is architecture specific
code.

I tried updating the bus-virt-phys-mapping.rst documentation, which
started as an email from Linus to explain some details of the Linux-2.0
driver interfaces. The bits about virt_to_bus() were declared obsolete
backin 2000, and the rest is not all that relevant any more, so in the
end I just decided to remove the file completely.

Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Acked-by: Helge Deller <deller@gmx.de> # parisc
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

Author: arndb

Documentation/core-api/bus-virt-phys-mapping.rst

@@ -707,20 +707,6 @@ to use the dma_sync_*() interfaces::
 		}
 	}
 
-Drivers converted fully to this interface should not use virt_to_bus() any
-longer, nor should they use bus_to_virt(). Some drivers have to be changed a
-little bit, because there is no longer an equivalent to bus_to_virt() in the
-dynamic DMA mapping scheme - you have to always store the DMA addresses
-returned by the dma_alloc_coherent(), dma_pool_alloc(), and dma_map_single()
-calls (dma_map_sg() stores them in the scatterlist itself if the platform
-supports dynamic DMA mapping in hardware) in your driver structures and/or
-in the card registers.
-
-All drivers should be using these interfaces with no exceptions.  It
-is planned to completely remove virt_to_bus() and bus_to_virt() as
-they are entirely deprecated.  Some ports already do not provide these
-as it is impossible to correctly support them.
-
 Handling Errors
 ===============
 

Documentation/core-api/dma-api-howto.rst

@@ -41,7 +41,6 @@ Library functionality that is used throughout the kernel.
    rbtree
    generic-radix-tree
    packing
-   bus-virt-phys-mapping
    this_cpu_ops
    timekeeping
    errseq

Documentation/core-api/index.rst

@@ -52,7 +52,6 @@ Todolist:
    circular-buffers
    generic-radix-tree
    packing
-   bus-virt-phys-mapping
    this_cpu_ops
    timekeeping
    errseq

Documentation/translations/zh_CN/core-api/index.rst

@@ -17,7 +17,6 @@ config ALPHA
 	select HAVE_PERF_EVENTS
 	select NEED_DMA_MAP_STATE
 	select NEED_SG_DMA_LENGTH
-	select VIRT_TO_BUS
 	select GENERIC_IRQ_PROBE
 	select GENERIC_PCI_IOMAP
 	select AUTO_IRQ_AFFINITY if SMP

arch/alpha/Kconfig

@@ -20,7 +20,7 @@
 #define fd_free_dma()           free_dma(FLOPPY_DMA)
 #define fd_clear_dma_ff()       clear_dma_ff(FLOPPY_DMA)
 #define fd_set_dma_mode(mode)   set_dma_mode(FLOPPY_DMA,mode)
-#define fd_set_dma_addr(addr)   set_dma_addr(FLOPPY_DMA,virt_to_bus(addr))
+#define fd_set_dma_addr(addr)   set_dma_addr(FLOPPY_DMA,isa_virt_to_bus(addr))
 #define fd_set_dma_count(count) set_dma_count(FLOPPY_DMA,count)
 #define fd_enable_irq()         enable_irq(FLOPPY_IRQ)
 #define fd_disable_irq()        disable_irq(FLOPPY_IRQ)

arch/alpha/include/asm/floppy.h

@@ -106,15 +106,15 @@ static inline void * phys_to_virt(unsigned long address)
 extern unsigned long __direct_map_base;
 extern unsigned long __direct_map_size;
 
-static inline unsigned long __deprecated virt_to_bus(volatile void *address)
+static inline unsigned long __deprecated isa_virt_to_bus(volatile void *address)
 {
 	unsigned long phys = virt_to_phys(address);
 	unsigned long bus = phys + __direct_map_base;
 	return phys <= __direct_map_size ? bus : 0;
 }
-#define isa_virt_to_bus virt_to_bus
+#define isa_virt_to_bus isa_virt_to_bus
 
-static inline void * __deprecated bus_to_virt(unsigned long address)
+static inline void * __deprecated isa_bus_to_virt(unsigned long address)
 {
 	void *virt;
 
@@ -125,7 +125,7 @@ static inline void * __deprecated bus_to_virt(unsigned long address)
 	virt = phys_to_virt(address);
 	return (long)address <= 0 ? NULL : virt;
 }
-#define isa_bus_to_virt bus_to_virt
+#define isa_bus_to_virt isa_bus_to_virt
 
 /*
  * There are different chipsets to interface the Alpha CPUs to the world.

arch/alpha/include/asm/io.h

@@ -39,7 +39,6 @@ config IA64
 	select HAVE_FUNCTION_DESCRIPTORS
 	select HAVE_VIRT_CPU_ACCOUNTING
 	select HUGETLB_PAGE_SIZE_VARIABLE if HUGETLB_PAGE
-	select VIRT_TO_BUS
 	select GENERIC_IRQ_PROBE
 	select GENERIC_PENDING_IRQ if SMP
 	select GENERIC_IRQ_SHOW

arch/ia64/Kconfig

@@ -96,14 +96,6 @@ extern u64 kern_mem_attribute (unsigned long phys_addr, unsigned long size);
 extern int valid_phys_addr_range (phys_addr_t addr, size_t count); /* efi.c */
 extern int valid_mmap_phys_addr_range (unsigned long pfn, size_t count);
 
-/*
- * The following two macros are deprecated and scheduled for removal.
- * Please use the PCI-DMA interface defined in <asm/pci.h> instead.
- */
-#define bus_to_virt	phys_to_virt
-#define virt_to_bus	virt_to_phys
-#define page_to_bus	page_to_phys
-
 # endif /* KERNEL */
 
 /*

arch/ia64/include/asm/io.h

@@ -30,7 +30,6 @@ config M68K
 	select OLD_SIGACTION
 	select OLD_SIGSUSPEND3
 	select UACCESS_MEMCPY if !MMU
-	select VIRT_TO_BUS
 	select ZONE_DMA
 
 config CPU_BIG_ENDIAN