[IA64] paraviatualize /dev/mem to enable X.

Signed-off-by: Isaku Yamahata <yamahata@valinux.co.jp>

5 files changed, 104 insertions, 4 deletions

diff --git a/linux-2.6-xen-sparse/arch/ia64/Kconfig b/linux-2.6-xen-sparse/arch/ia64/Kconfig
index 4073a04638..5a3768d779 100644
--- a/linux-2.6-xen-sparse/arch/ia64/Kconfig
+++ b/linux-2.6-xen-sparse/arch/ia64/Kconfig
@@ -533,9 +533,6 @@ config XEN_BALLOON
 config XEN_SKBUFF
 	default y
 
-config XEN_DEVMEM
-	default n
-
 config XEN_REBOOT
 	default y
 
diff --git a/linux-2.6-xen-sparse/arch/ia64/xen/Makefile b/linux-2.6-xen-sparse/arch/ia64/xen/Makefile
index 36434aac72..6bd31af099 100644
--- a/linux-2.6-xen-sparse/arch/ia64/xen/Makefile
+++ b/linux-2.6-xen-sparse/arch/ia64/xen/Makefile
@@ -4,6 +4,6 @@
 
 obj-y := hypercall.o xenivt.o xenentry.o xensetup.o xenpal.o xenhpski.o \
 	 hypervisor.o pci-dma-xen.o util.o xencomm.o xcom_hcall.o \
-	 xcom_mini.o xcom_privcmd.o
+	 xcom_mini.o xcom_privcmd.o mem.o
 
 pci-dma-xen-y := ../../i386/kernel/pci-dma-xen.o
diff --git a/linux-2.6-xen-sparse/arch/ia64/xen/mem.c b/linux-2.6-xen-sparse/arch/ia64/xen/mem.c
new file mode 100644
index 0000000000..1c995b6f11
--- /dev/null
+++ b/linux-2.6-xen-sparse/arch/ia64/xen/mem.c
@@ -0,0 +1,76 @@
+/*
+ *  Originally from linux/drivers/char/mem.c
+ *
+ *  Copyright (C) 1991, 1992  Linus Torvalds
+ *
+ *  Added devfs support. 
+ *    Jan-11-1998, C. Scott Ananian <cananian@alumni.princeton.edu>
+ *  Shared /dev/zero mmaping support, Feb 2000, Kanoj Sarcar <kanoj@sgi.com>
+ */
+/*
+ * taken from
+ * linux/drivers/char/mem.c and linux-2.6-xen-sparse/drivers/xen/char/mem.c.
+ * adjusted for IA64 and made transparent.
+ * Copyright (c) 2006 Isaku Yamahata <yamahata at valinux co jp>
+ *                    VA Linux Systems Japan K.K.
+ */
+
+#include <linux/config.h>
+#include <linux/mm.h>
+#include <linux/efi.h>
+
+/*
+ * Architectures vary in how they handle caching for addresses
+ * outside of main memory.
+ *
+ */
+static inline int uncached_access(struct file *file, unsigned long addr)
+{
+	/*
+	 * On ia64, we ignore O_SYNC because we cannot tolerate memory attribute aliases.
+	 */
+	return !(efi_mem_attributes(addr) & EFI_MEMORY_WB);
+}
+
+int xen_mmap_mem(struct file * file, struct vm_area_struct * vma)
+{
+	unsigned long addr = vma->vm_pgoff << PAGE_SHIFT;
+	size_t size = vma->vm_end - vma->vm_start;
+
+
+#if 0
+	/*
+	 *XXX FIXME: linux-2.6.16.29, linux-2.6.17
+	 *    valid_mmap_phys_addr_range() in linux/arch/ia64/kernel/efi.c
+	 *    fails checks.
+	 *    linux-2.6.18.1's returns always 1. 
+	 *    Its comments says
+	 *
+         * MMIO regions are often missing from the EFI memory map.
+         * We must allow mmap of them for programs like X, so we
+         * currently can't do any useful validation.
+         */
+	if (!valid_mmap_phys_addr_range(addr, &size))
+		return -EINVAL;
+	if (size < vma->vm_end - vma->vm_start)
+		return -EINVAL;
+#endif
+
+	if (is_running_on_xen()) {
+		unsigned long offset = HYPERVISOR_ioremap(addr, size);
+		if (IS_ERR_VALUE(offset))
+			return offset;
+	}
+
+	if (uncached_access(file, vma->vm_pgoff << PAGE_SHIFT))
+		vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
+
+        /* Remap-pfn-range will mark the range VM_IO and VM_RESERVED */
+        if (remap_pfn_range(vma,
+                            vma->vm_start,
+                            vma->vm_pgoff,
+                            size,
+                            vma->vm_page_prot))
+                return -EAGAIN;
+        return 0;
+}
diff --git a/linux-2.6-xen-sparse/include/asm-ia64/io.h b/linux-2.6-xen-sparse/include/asm-ia64/io.h
index a841d78d79..73c9b60904 100644
--- a/linux-2.6-xen-sparse/include/asm-ia64/io.h
+++ b/linux-2.6-xen-sparse/include/asm-ia64/io.h
@@ -129,6 +129,11 @@ extern int valid_mmap_phys_addr_range (unsigned long addr, size_t *count);
 	(((bvec_to_bus((vec1)) + (vec1)->bv_len) == bvec_to_bus((vec2))) && \
 	 ((bvec_to_pseudophys((vec1)) + (vec1)->bv_len) ==		\
 	  bvec_to_pseudophys((vec2))))
+
+/* We will be supplying our own /dev/mem implementation */
+#define ARCH_HAS_DEV_MEM
+#define ARCH_HAS_DEV_MEM_MMAP_MEM
+int xen_mmap_mem(struct file * file, struct vm_area_struct * vma);
 #endif /* CONFIG_XEN */
 
 # endif /* KERNEL */
@@ -458,6 +463,8 @@ static inline void __iomem *
 ioremap (unsigned long offset, unsigned long size)
 {
 	offset = HYPERVISOR_ioremap(offset, size);
+	if (IS_ERR_VALUE(offset))
+		return (void __iomem*)offset;
 	return (void __iomem *) (__IA64_UNCACHED_OFFSET | (offset));
 }
 
diff --git a/linux-2.6-xen-sparse/include/asm-ia64/uaccess.h b/linux-2.6-xen-sparse/include/asm-ia64/uaccess.h
index 9adb51211c..e015fd0d3b 100644
--- a/linux-2.6-xen-sparse/include/asm-ia64/uaccess.h
+++ b/linux-2.6-xen-sparse/include/asm-ia64/uaccess.h
@@ -365,6 +365,7 @@ ia64_done_with_exception (struct pt_regs *regs)
 }
 
 #define ARCH_HAS_TRANSLATE_MEM_PTR	1
+#ifndef CONFIG_XEN
 static __inline__ char *
 xlate_dev_mem_ptr (unsigned long p)
 {
@@ -379,6 +380,25 @@ xlate_dev_mem_ptr (unsigned long p)
 
 	return ptr;
 }
+#else
+static __inline__ char *
+xlate_dev_mem_ptr (unsigned long p, ssize_t sz)
+{
+	unsigned long pfn = p >> PAGE_SHIFT;
+
+	if (pfn_valid(pfn) && !PageUncached(pfn_to_page(pfn)))
+		return __va(p);
+
+	return ioremap(p, sz);
+}
+
+static __inline__ void
+xlate_dev_mem_ptr_unmap (char* v)
+{
+	if (REGION_NUMBER(v) == RGN_UNCACHED)
+		iounmap(v);
+}
+#endif
 
 /*
  * Convert a virtual cached kernel memory pointer to an uncached pointer