um: Remove broken highmem support

Highmem was always buggy and experimental on UML(i386).
In times where 64 bit computers are default we can
remove that experimental code.

Signed-off-by: Richard Weinberger <richard@nod.at>

5 files changed, 1 insertions, 92 deletions

diff --git a/arch/um/Kconfig.um b/arch/um/Kconfig.um
index ff86fbedc2fc..8c46978ff70b 100644
--- a/arch/um/Kconfig.um
+++ b/arch/um/Kconfig.um
@@ -95,18 +95,6 @@ config MAGIC_SYSRQ
           The keys are documented in <file:Documentation/sysrq.txt>. Don't say Y
           unless you really know what this hack does.
 
-config HIGHMEM
-        bool "Highmem support"
-        depends on !64BIT && BROKEN
-        default n
-        help
-          This was used to allow UML to run with big amounts of memory.
-          Currently it is unstable, so if unsure say N.
-
-          To use big amounts of memory, it is recommended enable static
-          linking (i.e. CONFIG_STATIC_LINK) - this should allow the
-          guest to use up to 2.75G of memory.
-
 config KERNEL_STACK_ORDER
         int "Kernel stack size order"
         default 1 if 64BIT
diff --git a/arch/um/include/asm/fixmap.h b/arch/um/include/asm/fixmap.h
index 3094ea3c73b0..1761fd75bf13 100644
--- a/arch/um/include/asm/fixmap.h
+++ b/arch/um/include/asm/fixmap.h
@@ -33,10 +33,6 @@
  * fix-mapped?
  */
 enum fixed_addresses {
-#ifdef CONFIG_HIGHMEM
-        FIX_KMAP_BEGIN, /* reserved pte's for temporary kernel mappings */
-        FIX_KMAP_END = FIX_KMAP_BEGIN+(KM_TYPE_NR*NR_CPUS)-1,
-#endif
         __end_of_fixed_addresses
 };
 
diff --git a/arch/um/include/asm/pgtable.h b/arch/um/include/asm/pgtable.h
index 2324b624f195..18eb9924dda3 100644
--- a/arch/um/include/asm/pgtable.h
+++ b/arch/um/include/asm/pgtable.h
@@ -47,11 +47,7 @@ extern unsigned long end_iomem;
 #define VMALLOC_OFFSET  (__va_space)
 #define VMALLOC_START ((end_iomem + VMALLOC_OFFSET) & ~(VMALLOC_OFFSET-1))
 #define PKMAP_BASE ((FIXADDR_START - LAST_PKMAP * PAGE_SIZE) & PMD_MASK)
-#ifdef CONFIG_HIGHMEM
-# define VMALLOC_END    (PKMAP_BASE-2*PAGE_SIZE)
-#else
-# define VMALLOC_END    (FIXADDR_START-2*PAGE_SIZE)
-#endif
+#define VMALLOC_END     (FIXADDR_START-2*PAGE_SIZE)
 #define MODULES_VADDR   VMALLOC_START
 #define MODULES_END     VMALLOC_END
 #define MODULES_LEN     (MODULES_VADDR - MODULES_END)
diff --git a/arch/um/kernel/mem.c b/arch/um/kernel/mem.c
index 8636e905426f..b2a2dff50b4e 100644
--- a/arch/um/kernel/mem.c
+++ b/arch/um/kernel/mem.c
@@ -38,19 +38,6 @@ int kmalloc_ok = 0;
 /* Used during early boot */
 static unsigned long brk_end;
 
-#ifdef CONFIG_HIGHMEM
-static void setup_highmem(unsigned long highmem_start,
-                          unsigned long highmem_len)
-{
-        unsigned long highmem_pfn;
-        int i;
-
-        highmem_pfn = __pa(highmem_start) >> PAGE_SHIFT;
-        for (i = 0; i < highmem_len >> PAGE_SHIFT; i++)
-                free_highmem_page(&mem_map[highmem_pfn + i]);
-}
-#endif
-
 void __init mem_init(void)
 {
         /* clear the zero-page */
@@ -67,9 +54,6 @@ void __init mem_init(void)
         /* this will put all low memory onto the freelists */
         free_all_bootmem();
         max_low_pfn = totalram_pages;
-#ifdef CONFIG_HIGHMEM
-        setup_highmem(end_iomem, highmem);
-#endif
         max_pfn = totalram_pages;
         mem_init_print_info(NULL);
         kmalloc_ok = 1;
@@ -127,49 +111,6 @@ static void __init fixrange_init(unsigned long start, unsigned long end,
         }
 }
 
-#ifdef CONFIG_HIGHMEM
-pte_t *kmap_pte;
-pgprot_t kmap_prot;
-
-#define kmap_get_fixmap_pte(vaddr)                                      \
-        pte_offset_kernel(pmd_offset(pud_offset(pgd_offset_k(vaddr), (vaddr)),\
-                                     (vaddr)), (vaddr))
-
-static void __init kmap_init(void)
-{
-        unsigned long kmap_vstart;
-
-        /* cache the first kmap pte */
-        kmap_vstart = __fix_to_virt(FIX_KMAP_BEGIN);
-        kmap_pte = kmap_get_fixmap_pte(kmap_vstart);
-
-        kmap_prot = PAGE_KERNEL;
-}
-
-static void __init init_highmem(void)
-{
-        pgd_t *pgd;
-        pud_t *pud;
-        pmd_t *pmd;
-        pte_t *pte;
-        unsigned long vaddr;
-
-        /*
-         * Permanent kmaps:
-         */
-        vaddr = PKMAP_BASE;
-        fixrange_init(vaddr, vaddr + PAGE_SIZE*LAST_PKMAP, swapper_pg_dir);
-
-        pgd = swapper_pg_dir + pgd_index(vaddr);
-        pud = pud_offset(pgd, vaddr);
-        pmd = pmd_offset(pud, vaddr);
-        pte = pte_offset_kernel(pmd, vaddr);
-        pkmap_page_table = pte;
-
-        kmap_init();
-}
-#endif /* CONFIG_HIGHMEM */
-
 static void __init fixaddr_user_init( void)
 {
 #ifdef CONFIG_ARCH_REUSE_HOST_VSYSCALL_AREA
@@ -211,9 +152,6 @@ void __init paging_init(void)
 
         zones_size[ZONE_NORMAL] = (end_iomem >> PAGE_SHIFT) -
                 (uml_physmem >> PAGE_SHIFT);
-#ifdef CONFIG_HIGHMEM
-        zones_size[ZONE_HIGHMEM] = highmem >> PAGE_SHIFT;
-#endif
         free_area_init(zones_size);
 
         /*
@@ -224,10 +162,6 @@ void __init paging_init(void)
         fixrange_init(vaddr, FIXADDR_TOP, swapper_pg_dir);
 
         fixaddr_user_init();
-
-#ifdef CONFIG_HIGHMEM
-        init_highmem();
-#endif
 }
 
 /*
diff --git a/arch/um/kernel/um_arch.c b/arch/um/kernel/um_arch.c
index cd09285facf4..9b06957e98ce 100644
--- a/arch/um/kernel/um_arch.c
+++ b/arch/um/kernel/um_arch.c
@@ -301,11 +301,6 @@ int __init linux_main(int argc, char **argv)
         if (physmem_size + iomem_size > max_physmem) {
                 highmem = physmem_size + iomem_size - max_physmem;
                 physmem_size -= highmem;
-#ifndef CONFIG_HIGHMEM
-                highmem = 0;
-                printf("CONFIG_HIGHMEM not enabled - physical memory shrunk "
-                       "to %Lu bytes\n", physmem_size);
-#endif
         }
 
         high_physmem = uml_physmem + physmem_size;