Merge ../linux-2.6-watchdog-mm

[linux-drm-fsl-dcu.git] / drivers / char / mem.c

diff --git a/drivers/char/mem.c b/drivers/char/mem.c
index 70f3954d6dfd2f408db10a558b07f80c538dc4ac..55473371b7c6934abe8486af6fc3055701187140 100644 (file)
--- a/drivers/char/mem.c
+++ b/drivers/char/mem.c
@@ -26,6 +26,7 @@
 #include <linux/backing-dev.h>
 #include <linux/bootmem.h>
 #include <linux/pipe_fs_i.h>
+#include <linux/pfn.h>
 
 #include <asm/uaccess.h>
 #include <asm/io.h>
@@ -95,7 +96,7 @@ static inline int valid_phys_addr_range(unsigned long addr, size_t count)
        return 1;
 }
 
-static inline int valid_mmap_phys_addr_range(unsigned long addr, size_t size)
+static inline int valid_mmap_phys_addr_range(unsigned long pfn, size_t size)
 {
        return 1;
 }
@@ -238,13 +239,42 @@ static pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
 }
 #endif
 
+#ifndef CONFIG_MMU
+static unsigned long get_unmapped_area_mem(struct file *file,
+                                          unsigned long addr,
+                                          unsigned long len,
+                                          unsigned long pgoff,
+                                          unsigned long flags)
+{
+       if (!valid_mmap_phys_addr_range(pgoff, len))
+               return (unsigned long) -EINVAL;
+       return pgoff;
+}
+
+/* can't do an in-place private mapping if there's no MMU */
+static inline int private_mapping_ok(struct vm_area_struct *vma)
+{
+       return vma->vm_flags & VM_MAYSHARE;
+}
+#else
+#define get_unmapped_area_mem  NULL
+
+static inline int private_mapping_ok(struct vm_area_struct *vma)
+{
+       return 1;
+}
+#endif
+
 static int mmap_mem(struct file * file, struct vm_area_struct * vma)
 {
        size_t size = vma->vm_end - vma->vm_start;
 
-       if (!valid_mmap_phys_addr_range(vma->vm_pgoff << PAGE_SHIFT, size))
+       if (!valid_mmap_phys_addr_range(vma->vm_pgoff, size))
                return -EINVAL;
 
+       if (!private_mapping_ok(vma))
+               return -ENOSYS;
+
        vma->vm_page_prot = phys_mem_access_prot(file, vma->vm_pgoff,
                                                 size,
                                                 vma->vm_page_prot);
@@ -263,8 +293,8 @@ static int mmap_kmem(struct file * file, struct vm_area_struct * vma)
 {
        unsigned long pfn;
 
-       /* Turn a kernel-virtual address into a physical page frame */
-       pfn = __pa((u64)vma->vm_pgoff << PAGE_SHIFT) >> PAGE_SHIFT;
+       /* Turn a pfn offset into an absolute pfn */
+       pfn = PFN_DOWN(virt_to_phys((void *)PAGE_OFFSET)) + vma->vm_pgoff;
 
        /*
         * RED-PEN: on some architectures there is more mapped memory
@@ -522,7 +552,7 @@ static ssize_t write_kmem(struct file * file, const char __user * buf,
        return virtr + wrote;
 }
 
-#if defined(CONFIG_ISA) || !defined(__mc68000__)
+#if (defined(CONFIG_ISA) || defined(CONFIG_PCI)) && !defined(__mc68000__)
 static ssize_t read_port(struct file * file, char __user * buf,
                         size_t count, loff_t *ppos)
 {
@@ -776,31 +806,33 @@ static int open_port(struct inode * inode, struct file * filp)
 #define open_kmem      open_mem
 #define open_oldmem    open_mem
 
-static struct file_operations mem_fops = {
+static const struct file_operations mem_fops = {
        .llseek         = memory_lseek,
        .read           = read_mem,
        .write          = write_mem,
        .mmap           = mmap_mem,
        .open           = open_mem,
+       .get_unmapped_area = get_unmapped_area_mem,
 };
 
-static struct file_operations kmem_fops = {
+static const struct file_operations kmem_fops = {
        .llseek         = memory_lseek,
        .read           = read_kmem,
        .write          = write_kmem,
        .mmap           = mmap_kmem,
        .open           = open_kmem,
+       .get_unmapped_area = get_unmapped_area_mem,
 };
 
-static struct file_operations null_fops = {
+static const struct file_operations null_fops = {
        .llseek         = null_lseek,
        .read           = read_null,
        .write          = write_null,
        .splice_write   = splice_write_null,
 };
 
-#if defined(CONFIG_ISA) || !defined(__mc68000__)
-static struct file_operations port_fops = {
+#if (defined(CONFIG_ISA) || defined(CONFIG_PCI)) && !defined(__mc68000__)
+static const struct file_operations port_fops = {
        .llseek         = memory_lseek,
        .read           = read_port,
        .write          = write_port,
@@ -808,25 +840,29 @@ static struct file_operations port_fops = {
 };
 #endif
 
-static struct file_operations zero_fops = {
+static const struct file_operations zero_fops = {
        .llseek         = zero_lseek,
        .read           = read_zero,
        .write          = write_zero,
        .mmap           = mmap_zero,
 };
 
+/*
+ * capabilities for /dev/zero
+ * - permits private mappings, "copies" are taken of the source of zeros
+ */
 static struct backing_dev_info zero_bdi = {
        .capabilities   = BDI_CAP_MAP_COPY,
 };
 
-static struct file_operations full_fops = {
+static const struct file_operations full_fops = {
        .llseek         = full_lseek,
        .read           = read_full,
        .write          = write_full,
 };
 
 #ifdef CONFIG_CRASH_DUMP
-static struct file_operations oldmem_fops = {
+static const struct file_operations oldmem_fops = {
        .read   = read_oldmem,
        .open   = open_oldmem,
 };
@@ -853,7 +889,7 @@ static ssize_t kmsg_write(struct file * file, const char __user * buf,
        return ret;
 }
 
-static struct file_operations kmsg_fops = {
+static const struct file_operations kmsg_fops = {
        .write =        kmsg_write,
 };
 
@@ -862,14 +898,18 @@ static int memory_open(struct inode * inode, struct file * filp)
        switch (iminor(inode)) {
                case 1:
                        filp->f_op = &mem_fops;
+                       filp->f_mapping->backing_dev_info =
+                               &directly_mappable_cdev_bdi;
                        break;
                case 2:
                        filp->f_op = &kmem_fops;
+                       filp->f_mapping->backing_dev_info =
+                               &directly_mappable_cdev_bdi;
                        break;
                case 3:
                        filp->f_op = &null_fops;
                        break;
-#if defined(CONFIG_ISA) || !defined(__mc68000__)
+#if (defined(CONFIG_ISA) || defined(CONFIG_PCI)) && !defined(__mc68000__)
                case 4:
                        filp->f_op = &port_fops;
                        break;
@@ -903,7 +943,7 @@ static int memory_open(struct inode * inode, struct file * filp)
        return 0;
 }
 
-static struct file_operations memory_fops = {
+static const struct file_operations memory_fops = {
        .open           = memory_open,  /* just a selector for the real open */
 };
 
@@ -916,7 +956,7 @@ static const struct {
        {1, "mem",     S_IRUSR | S_IWUSR | S_IRGRP, &mem_fops},
        {2, "kmem",    S_IRUSR | S_IWUSR | S_IRGRP, &kmem_fops},
        {3, "null",    S_IRUGO | S_IWUGO,           &null_fops},
-#if defined(CONFIG_ISA) || !defined(__mc68000__)
+#if (defined(CONFIG_ISA) || defined(CONFIG_PCI)) && !defined(__mc68000__)
        {4, "port",    S_IRUSR | S_IWUSR | S_IRGRP, &port_fops},
 #endif
        {5, "zero",    S_IRUGO | S_IWUGO,           &zero_fops},