Fixed highmem support.

5 files changed, 134 insertions, 42 deletions

diff --git a/arch/um/include/mem_user.h b/arch/um/include/mem_user.h
index b0e01a9..fe0c298 100644
--- a/arch/um/include/mem_user.h
+++ b/arch/um/include/mem_user.h
@@ -49,19 +49,21 @@ extern int iomem_size;
 extern unsigned long host_task_size;
 extern unsigned long task_size;
 
+extern void check_devanon(void);
 extern int init_mem_user(void);
 extern int create_mem_file(unsigned long len);
 extern void setup_memory(void *entry);
 extern unsigned long find_iomem(char *driver, unsigned long *len_out);
-extern int init_maps(unsigned long len);
+extern int init_maps(unsigned long physmem, unsigned long iomem, 
+		     unsigned long highmem);
 extern unsigned long get_vm(unsigned long len);
 extern void setup_physmem(unsigned long start, unsigned long usable,
-			  unsigned long len);
+			  unsigned long len, unsigned long highmem);
 extern void add_iomem(char *name, int fd, unsigned long size);
 extern unsigned long phys_offset(unsigned long phys);
 extern void unmap_physmem(void);
-extern int map_memory(unsigned long virt, unsigned long phys, 
-		      unsigned long len, int r, int w, int x);
+extern void map_memory(unsigned long virt, unsigned long phys, 
+		       unsigned long len, int r, int w, int x);
 extern int protect_memory(unsigned long addr, unsigned long len, 
 			  int r, int w, int x, int must_succeed);
 extern unsigned long get_kmem_end(void);
diff --git a/arch/um/kernel/mem.c b/arch/um/kernel/mem.c
index aba6258..8dd6327 100644
--- a/arch/um/kernel/mem.c
+++ b/arch/um/kernel/mem.c
@@ -40,14 +40,31 @@ static void map_cb(void *unused)
 	map_memory(brk_end, __pa(brk_end), uml_reserved - brk_end, 1, 1, 0);
 }
 
-void mem_init(void)
+#ifdef CONFIG_HIGHMEM
+static void setup_highmem(unsigned long highmem_start, 
+			  unsigned long highmem_len)
 {
-	unsigned long start;
+	struct page *page;
+	unsigned long highmem_pfn;
+	int i;
 
-#ifdef CONFIG_HIGHMEM
-	highmem_start_page = phys_page(__pa(high_physmem));
+	highmem_start_page = virt_to_page(highmem_start);
+
+	highmem_pfn = __pa(highmem_start) >> PAGE_SHIFT;
+	for(i = 0; i < highmem_len >> PAGE_SHIFT; i++){
+		page = &mem_map[highmem_pfn + i];
+		ClearPageReserved(page);
+		set_bit(PG_highmem, &page->flags);
+		atomic_set(&page->count, 1);
+		__free_page(page);
+	}
+}
 #endif
 
+void mem_init(void)
+{
+	unsigned long start;
+
         /* clear the zero-page */
         memset((void *) empty_zero_page, 0, PAGE_SIZE);
 
@@ -74,6 +91,10 @@ void mem_init(void)
 	printk(KERN_INFO "Memory: %luk available\n", 
 	       (unsigned long) nr_free_pages() << (PAGE_SHIFT-10));
 	kmalloc_ok = 1;
+
+#ifdef CONFIG_HIGHMEM
+	setup_highmem(end_iomem, highmem);
+#endif
 }
 
 static void __init fixrange_init(unsigned long start, unsigned long end, 
@@ -106,6 +127,47 @@ static void __init fixrange_init(unsigned long start, unsigned long end,
 	}
 }
 
+#if CONFIG_HIGHMEM
+pte_t *kmap_pte;
+pgprot_t kmap_prot;
+
+#define kmap_get_fixmap_pte(vaddr)					\
+	pte_offset(pmd_offset(pgd_offset_k(vaddr), (vaddr)), (vaddr))
+
+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_highmem(void)
+{
+	pgd_t *pgd;
+	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_offset(vaddr);
+	pmd = pmd_offset(pgd, vaddr);
+	pte = pte_offset(pmd, vaddr);
+	pkmap_page_table = pte;
+
+	kmap_init();
+}
+
+#endif /* CONFIG_HIGHMEM */
+
 void paging_init(void)
 {
 	unsigned long zones_size[MAX_NR_ZONES], vaddr;
@@ -115,8 +177,7 @@ void paging_init(void)
 	empty_bad_page = (unsigned long *) alloc_bootmem_low_pages(PAGE_SIZE);
 	for(i=0;i<sizeof(zones_size)/sizeof(zones_size[0]);i++) 
 		zones_size[i] = 0;
-	zones_size[0] = (high_physmem >> PAGE_SHIFT) - 
-		(uml_physmem >> PAGE_SHIFT);
+	zones_size[0] = (end_iomem >> PAGE_SHIFT) - (uml_physmem >> PAGE_SHIFT);
 	zones_size[2] = highmem >> PAGE_SHIFT;
 	free_area_init(zones_size);
 
@@ -129,7 +190,6 @@ void paging_init(void)
 
 #if CONFIG_HIGHMEM
 	init_highmem();
-	setup_highmem(highmem);
 #endif
 }
 
diff --git a/arch/um/kernel/physmem.c b/arch/um/kernel/physmem.c
index 0ccab50..787c59c 100644
--- a/arch/um/kernel/physmem.c
+++ b/arch/um/kernel/physmem.c
@@ -133,24 +133,36 @@ unsigned long to_phys(void *virt)
 	return(((unsigned long) virt) - uml_physmem);
 }
 
-int init_maps(unsigned long len)
+int init_maps(unsigned long physmem, unsigned long iomem, unsigned long highmem)
 {
 	struct page *p, *map;
-	int i, n;
+	unsigned long phys_len, phys_pages, highmem_len, highmem_pages;
+	unsigned long iomem_len, iomem_pages, total_len, total_pages;
+	int i;
+
+	phys_pages = physmem >> PAGE_SHIFT;
+	phys_len = phys_pages * sizeof(struct page);
+
+	iomem_pages = iomem >> PAGE_SHIFT;
+	iomem_len = iomem_pages * sizeof(struct page);
+
+	highmem_pages = highmem >> PAGE_SHIFT;
+	highmem_len = highmem_pages * sizeof(struct page);
 
-	n = len >> PAGE_SHIFT;
-	len = n * sizeof(struct page);
+	total_pages = phys_pages + iomem_pages + highmem_pages;
+	total_len = phys_len + iomem_pages + highmem_len;
 
 	if(kmalloc_ok){
-		map = kmalloc(len, GFP_KERNEL);
-		if(map == NULL) map = vmalloc(len);
+		map = kmalloc(total_len, GFP_KERNEL);
+		if(map == NULL) 
+			map = vmalloc(total_len);
 	}
-	else map = alloc_bootmem_low_pages(len);
+	else map = alloc_bootmem_low_pages(total_len);
 
 	if(map == NULL)
 		return(-ENOMEM);
 
-	for(i = 0; i < n; i++){
+	for(i = 0; i < total_pages; i++){
 		p = &map[i];
 		set_page_count(p, 0);
 		SetPageReserved(p);
@@ -158,22 +170,23 @@ int init_maps(unsigned long len)
 	}
 
 	mem_map = map;
-	max_mapnr = n;
+	max_mapnr = total_pages;
 	return(0);
 }
 
-struct page *__virt_to_page(const unsigned long virt)
+struct page *phys_to_page(const unsigned long phys)
 {
-	int index = (virt - uml_physmem) >> PAGE_SHIFT;
+	return(&mem_map[phys >> PAGE_SHIFT]);
+}
 
-	return(&mem_map[index]);
+struct page *__virt_to_page(const unsigned long virt)
+{
+	return(&mem_map[__pa(virt) >> PAGE_SHIFT]);
 }
 
 unsigned long page_to_phys(struct page *page)
 {
-	int index = page - mem_map;
-
-	return(virt_to_phys((void *) (uml_physmem + (index << PAGE_SHIFT))));
+	return((page - mem_map) << PAGE_SHIFT);
 }
 
 pte_t mk_pte(struct page *page, pgprot_t pgprot)
@@ -195,27 +208,30 @@ unsigned long get_kmem_end(void)
 	return(kmem_top);
 }
 
-int map_memory(unsigned long virt, unsigned long phys, unsigned long len, 
-	       int r, int w, int x)
+void map_memory(unsigned long virt, unsigned long phys, unsigned long len, 
+		int r, int w, int x)
 {
 	__u64 offset;
-	int fd;
+	int fd, err;
 
 	fd = phys_mapping(phys, &offset);
-	return(os_map_memory((void *) virt, fd, offset, len, r, w, x));
+	err = os_map_memory((void *) virt, fd, offset, len, r, w, x);
+	if(err)
+		panic("map_memory(0x%lx, %d, 0x%llx, %ld, %d, %d, %d) failed, "
+		      "err = %d\n", virt, fd, offset, len, r, w, x, err);
 }
 
 #define PFN_UP(x) (((x) + PAGE_SIZE-1) >> PAGE_SHIFT)
 
 void setup_physmem(unsigned long start, unsigned long reserve_end,
-		   unsigned long len)
+		   unsigned long len, unsigned long highmem)
 {
 	unsigned long reserve = reserve_end - start;
 	int pfn = PFN_UP(__pa(reserve_end));
 	int delta = (len - reserve) >> PAGE_SHIFT;
 	int err, offset, bootmap_size;
 
-	physmem_fd = create_mem_file(len);
+	physmem_fd = create_mem_file(len + highmem);
 
 	offset = uml_reserved - uml_physmem;
 	err = os_map_memory((void *) uml_reserved, physmem_fd, offset, 
@@ -240,11 +256,11 @@ int phys_mapping(unsigned long phys, __u64 *offset_out)
 		fd = desc->fd;
 		*offset_out = desc->offset;
 	}
-	else if((phys >= 0) && (phys < physmem_size)){
+	else if(phys < physmem_size){
 		fd = physmem_fd;
 		*offset_out = phys;
 	}
-	else {
+	else if(phys < __pa(end_iomem)){
 		struct iomem_region *region = iomem_regions;
 	
 		while(region != NULL){
@@ -257,6 +273,11 @@ int phys_mapping(unsigned long phys, __u64 *offset_out)
 			region = region->next;
 		}
 	}
+	else if(phys < __pa(end_iomem) + highmem){
+		fd = physmem_fd;
+		*offset_out = phys - iomem_size;
+	}
+
 	return(fd);
 }
 
diff --git a/arch/um/kernel/um_arch.c b/arch/um/kernel/um_arch.c
index 57b42ba..e8aeb22 100644
--- a/arch/um/kernel/um_arch.c
+++ b/arch/um/kernel/um_arch.c
@@ -336,9 +336,15 @@ int linux_main(int argc, char **argv)
 #endif
   
 	highmem = 0;
-	max_physmem = get_kmem_end() - uml_physmem - MIN_VMALLOC;
-	if(physmem_size > max_physmem){
-		highmem = physmem_size - max_physmem;
+	iomem_size = (iomem_size + PAGE_SIZE - 1) & PAGE_MASK;
+	max_physmem = get_kmem_end() - uml_physmem - iomem_size - MIN_VMALLOC;
+
+	/* Zones have to begin on a 1 << MAX_ORDER page boundary,
+	 * so this makes sure that's true for highmem
+	 */
+	max_physmem &= ~((1 << (PAGE_SHIFT + MAX_ORDER)) - 1);
+	if(physmem_size + iomem_size > max_physmem){
+		highmem = physmem_size + iomem_size - max_physmem;
 		physmem_size -= highmem;
 #ifndef CONFIG_HIGHMEM
 		highmem = 0;
@@ -348,15 +354,16 @@ int linux_main(int argc, char **argv)
 	}
 
 	high_physmem = uml_physmem + physmem_size;
-	high_memory = (void *) high_physmem;
-	end_iomem = high_physmem + PAGE_SIZE + iomem_size;
+	end_iomem = high_physmem + iomem_size;
+	high_memory = (void *) end_iomem;
 
 	start_vm = VMALLOC_START;
 
-	setup_physmem(uml_physmem, uml_reserved, physmem_size);
-	if(init_maps(physmem_size)){
+	setup_physmem(uml_physmem, uml_reserved, physmem_size, highmem);
+	if(init_maps(physmem_size, iomem_size, highmem)){
 		printf("Failed to allocate mem_map for %ld bytes of physical "
-		       "memory\n", physmem_size);
+		       "memory and %ld bytes of highmem\n", physmem_size,
+		       highmem);
 		exit(1);
 	}
 
@@ -410,6 +417,7 @@ void __init check_bugs(void)
 	arch_check_bugs();
 	check_ptrace();
 	check_sigio();
+	check_devanon();
 }
 
 /*
diff --git a/include/asm-um/pgtable.h b/include/asm-um/pgtable.h
index a226925..798e47d 100644
--- a/include/asm-um/pgtable.h
+++ b/include/asm-um/pgtable.h
@@ -206,6 +206,7 @@ static inline void pgd_clear(pgd_t * pgdp)	{ }
 #define pte_page(pte) virt_to_page(__va(pte_val(pte)))
 #define pmd_page(pmd) ((unsigned long) __va(pmd_val(pmd) & PAGE_MASK))
 
+extern struct page *phys_to_page(const unsigned long phys);
 extern struct page *__virt_to_page(const unsigned long virt);
 #define virt_to_page(addr) __virt_to_page((const unsigned long) addr)