[PATCH] media: ivtv: fix build for UML

[Randy Dunlap]

Prevent the use of page table macros and types from 2 conflicting
places. This fixes multiple build errors and warnings, e.g.:

../arch/x86/include/asm/pgtable_64_types.h:21:34: error: conflicting types for ‘pte_t’
 typedef struct { pteval_t pte; } pte_t;
                                  ^~~~~
In file included from ../include/linux/mm_types_task.h:16:0,
                 from ../include/linux/mm_types.h:5,
                 from ../include/linux/buildid.h:5,
                 from ../include/linux/module.h:14,
                 from ../drivers/media/pci/ivtv/ivtv-driver.h:40,
                 from ../drivers/media/pci/ivtv/ivtvfb.c:29:
../arch/um/include/asm/page.h:57:39: note: previous declaration of ‘pte_t’ was here
 typedef struct { unsigned long pte; } pte_t;

../arch/x86/include/asm/pgtable_types.h:284:43: error: expected ‘)’ before ‘prot’
 static inline pgprot_t pgprot_nx(pgprot_t prot)
                                           ^
../include/linux/pgtable.h:914:26: note: in definition of macro ‘pgprot_nx’
 #define pgprot_nx(prot) (prot)
                          ^~~~
In file included from ../arch/x86/include/asm/memtype.h:6:0,
                 from ../drivers/media/pci/ivtv/ivtvfb.c:40:
../arch/x86/include/asm/pgtable_types.h:288:0: warning: "pgprot_nx" redefined
 #define pgprot_nx pgprot_nx

../arch/x86/include/asm/page_types.h:11:0: warning: "PAGE_SIZE" redefined
 #define PAGE_SIZE  (_AC(1,UL) << PAGE_SHIFT)
 
In file included from ../include/linux/mm_types_task.h:16:0,
                 from ../include/linux/mm_types.h:5,
                 from ../include/linux/buildid.h:5,
                 from ../include/linux/module.h:14,
                 from ../drivers/media/pci/ivtv/ivtv-driver.h:40,
                 from ../drivers/media/pci/ivtv/ivtvfb.c:29:
../arch/um/include/asm/page.h:14:0: note: this is the location of the previous definition
 #define PAGE_SIZE (_AC(1, UL) << PAGE_SHIFT)

Fixes: 68f5d3f3b654 ("um: add PCI over virtio emulation driver")
Signed-off-by: Randy Dunlap <rdunlap at infradead.org>
Cc: Johannes Berg <johannes at sipsolutions.net>
Cc: Andy Walls <awalls at md.metrocast.net>
Cc: Mauro Carvalho Chehab <mchehab at kernel.org>
Cc: linux-media at vger.kernel.org
Cc: linux-um at lists.infradead.org
Cc: Richard Weinberger <richard at nod.at>
---
 drivers/media/pci/ivtv/ivtvfb.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

--- linux-next-20211007.orig/drivers/media/pci/ivtv/ivtvfb.c
+++ linux-next-20211007/drivers/media/pci/ivtv/ivtvfb.c
@@ -36,7 +36,7 @@
 #include <linux/fb.h>
 #include <linux/ivtvfb.h>
 
-#ifdef CONFIG_X86_64
+#if defined(CONFIG_X86_64) && !defined(CONFIG_UML)
 #include <asm/memtype.h>
 #endif
 
@@ -1157,7 +1157,7 @@ static int ivtvfb_init_card(struct ivtv
 {
 	int rc;
 
-#ifdef CONFIG_X86_64
+#if defined(CONFIG_X86_64) && !defined(CONFIG_UML)
 	if (pat_enabled()) {
 		if (ivtvfb_force_pat) {
 			pr_info("PAT is enabled. Write-combined framebuffer caching will be disabled.\n");