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-rw-r--r--drivers/char/mem.c195
1 files changed, 101 insertions, 94 deletions
diff --git a/drivers/char/mem.c b/drivers/char/mem.c
index 48788db4e28..1f3215ac085 100644
--- a/drivers/char/mem.c
+++ b/drivers/char/mem.c
@@ -3,7 +3,7 @@
*
* Copyright (C) 1991, 1992 Linus Torvalds
*
- * Added devfs support.
+ * Added devfs support.
* Jan-11-1998, C. Scott Ananian <cananian@alumni.princeton.edu>
* Shared /dev/zero mmapping support, Feb 2000, Kanoj Sarcar <kanoj@sgi.com>
*/
@@ -44,36 +44,6 @@ static inline unsigned long size_inside_page(unsigned long start,
return min(sz, size);
}
-/*
- * Architectures vary in how they handle caching for addresses
- * outside of main memory.
- *
- */
-static inline int uncached_access(struct file *file, unsigned long addr)
-{
-#if defined(CONFIG_IA64)
- /*
- * On ia64, we ignore O_DSYNC because we cannot tolerate memory attribute aliases.
- */
- return !(efi_mem_attributes(addr) & EFI_MEMORY_WB);
-#elif defined(CONFIG_MIPS)
- {
- extern int __uncached_access(struct file *file,
- unsigned long addr);
-
- return __uncached_access(file, addr);
- }
-#else
- /*
- * Accessing memory above the top the kernel knows about or through a file pointer
- * that was marked O_DSYNC will be done non-cached.
- */
- if (file->f_flags & O_DSYNC)
- return 1;
- return addr >= __pa(high_memory);
-#endif
-}
-
#ifndef ARCH_HAS_VALID_PHYS_ADDR_RANGE
static inline int valid_phys_addr_range(unsigned long addr, size_t count)
{
@@ -115,15 +85,15 @@ static inline int range_is_allowed(unsigned long pfn, unsigned long size)
}
#endif
-void __attribute__((weak)) unxlate_dev_mem_ptr(unsigned long phys, void *addr)
+void __weak unxlate_dev_mem_ptr(unsigned long phys, void *addr)
{
}
/*
- * This funcion reads the *physical* memory. The f_pos points directly to the
- * memory location.
+ * This funcion reads the *physical* memory. The f_pos points directly to the
+ * memory location.
*/
-static ssize_t read_mem(struct file * file, char __user * buf,
+static ssize_t read_mem(struct file *file, char __user *buf,
size_t count, loff_t *ppos)
{
unsigned long p = *ppos;
@@ -140,10 +110,10 @@ static ssize_t read_mem(struct file * file, char __user * buf,
if (sz > 0) {
if (clear_user(buf, sz))
return -EFAULT;
- buf += sz;
- p += sz;
- count -= sz;
- read += sz;
+ buf += sz;
+ p += sz;
+ count -= sz;
+ read += sz;
}
}
#endif
@@ -157,9 +127,9 @@ static ssize_t read_mem(struct file * file, char __user * buf,
return -EPERM;
/*
- * On ia64 if a page has been mapped somewhere as
- * uncached, then it must also be accessed uncached
- * by the kernel or data corruption may occur
+ * On ia64 if a page has been mapped somewhere as uncached, then
+ * it must also be accessed uncached by the kernel or data
+ * corruption may occur.
*/
ptr = xlate_dev_mem_ptr(p);
if (!ptr)
@@ -180,7 +150,7 @@ static ssize_t read_mem(struct file * file, char __user * buf,
return read;
}
-static ssize_t write_mem(struct file * file, const char __user * buf,
+static ssize_t write_mem(struct file *file, const char __user *buf,
size_t count, loff_t *ppos)
{
unsigned long p = *ppos;
@@ -212,9 +182,9 @@ static ssize_t write_mem(struct file * file, const char __user * buf,
return -EPERM;
/*
- * On ia64 if a page has been mapped somewhere as
- * uncached, then it must also be accessed uncached
- * by the kernel or data corruption may occur
+ * On ia64 if a page has been mapped somewhere as uncached, then
+ * it must also be accessed uncached by the kernel or data
+ * corruption may occur.
*/
ptr = xlate_dev_mem_ptr(p);
if (!ptr) {
@@ -242,13 +212,46 @@ static ssize_t write_mem(struct file * file, const char __user * buf,
return written;
}
-int __attribute__((weak)) phys_mem_access_prot_allowed(struct file *file,
+int __weak phys_mem_access_prot_allowed(struct file *file,
unsigned long pfn, unsigned long size, pgprot_t *vma_prot)
{
return 1;
}
#ifndef __HAVE_PHYS_MEM_ACCESS_PROT
+
+/*
+ * Architectures vary in how they handle caching for addresses
+ * outside of main memory.
+ *
+ */
+static int uncached_access(struct file *file, unsigned long addr)
+{
+#if defined(CONFIG_IA64)
+ /*
+ * On ia64, we ignore O_DSYNC because we cannot tolerate memory
+ * attribute aliases.
+ */
+ return !(efi_mem_attributes(addr) & EFI_MEMORY_WB);
+#elif defined(CONFIG_MIPS)
+ {
+ extern int __uncached_access(struct file *file,
+ unsigned long addr);
+
+ return __uncached_access(file, addr);
+ }
+#else
+ /*
+ * Accessing memory above the top the kernel knows about or through a
+ * file pointer
+ * that was marked O_DSYNC will be done non-cached.
+ */
+ if (file->f_flags & O_DSYNC)
+ return 1;
+ return addr >= __pa(high_memory);
+#endif
+}
+
static pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
unsigned long size, pgprot_t vma_prot)
{
@@ -294,7 +297,7 @@ static const struct vm_operations_struct mmap_mem_ops = {
#endif
};
-static int mmap_mem(struct file * file, struct vm_area_struct * vma)
+static int mmap_mem(struct file *file, struct vm_area_struct *vma)
{
size_t size = vma->vm_end - vma->vm_start;
@@ -329,7 +332,7 @@ static int mmap_mem(struct file * file, struct vm_area_struct * vma)
}
#ifdef CONFIG_DEVKMEM
-static int mmap_kmem(struct file * file, struct vm_area_struct * vma)
+static int mmap_kmem(struct file *file, struct vm_area_struct *vma)
{
unsigned long pfn;
@@ -337,9 +340,9 @@ static int mmap_kmem(struct file * file, struct vm_area_struct * vma)
pfn = __pa((u64)vma->vm_pgoff << PAGE_SHIFT) >> PAGE_SHIFT;
/*
- * RED-PEN: on some architectures there is more mapped memory
- * than available in mem_map which pfn_valid checks
- * for. Perhaps should add a new macro here.
+ * RED-PEN: on some architectures there is more mapped memory than
+ * available in mem_map which pfn_valid checks for. Perhaps should add a
+ * new macro here.
*
* RED-PEN: vmalloc is not supported right now.
*/
@@ -389,7 +392,7 @@ static ssize_t read_oldmem(struct file *file, char __user *buf,
/*
* This function reads the *virtual* memory as seen by the kernel.
*/
-static ssize_t read_kmem(struct file *file, char __user *buf,
+static ssize_t read_kmem(struct file *file, char __user *buf,
size_t count, loff_t *ppos)
{
unsigned long p = *ppos;
@@ -400,8 +403,8 @@ static ssize_t read_kmem(struct file *file, char __user *buf,
read = 0;
if (p < (unsigned long) high_memory) {
low_count = count;
- if (count > (unsigned long) high_memory - p)
- low_count = (unsigned long) high_memory - p;
+ if (count > (unsigned long)high_memory - p)
+ low_count = (unsigned long)high_memory - p;
#ifdef __ARCH_HAS_NO_PAGE_ZERO_MAPPED
/* we don't have page 0 mapped on sparc and m68k.. */
@@ -465,9 +468,8 @@ static ssize_t read_kmem(struct file *file, char __user *buf,
}
-static inline ssize_t
-do_write_kmem(unsigned long p, const char __user *buf,
- size_t count, loff_t *ppos)
+static ssize_t do_write_kmem(unsigned long p, const char __user *buf,
+ size_t count, loff_t *ppos)
{
ssize_t written, sz;
unsigned long copied;
@@ -491,9 +493,9 @@ do_write_kmem(unsigned long p, const char __user *buf,
sz = size_inside_page(p, count);
/*
- * On ia64 if a page has been mapped somewhere as
- * uncached, then it must also be accessed uncached
- * by the kernel or data corruption may occur
+ * On ia64 if a page has been mapped somewhere as uncached, then
+ * it must also be accessed uncached by the kernel or data
+ * corruption may occur.
*/
ptr = xlate_dev_kmem_ptr((char *)p);
@@ -514,11 +516,10 @@ do_write_kmem(unsigned long p, const char __user *buf,
return written;
}
-
/*
* This function writes to the *virtual* memory as seen by the kernel.
*/
-static ssize_t write_kmem(struct file * file, const char __user * buf,
+static ssize_t write_kmem(struct file *file, const char __user *buf,
size_t count, loff_t *ppos)
{
unsigned long p = *ppos;
@@ -570,17 +571,17 @@ static ssize_t write_kmem(struct file * file, const char __user * buf,
#endif
#ifdef CONFIG_DEVPORT
-static ssize_t read_port(struct file * file, char __user * buf,
+static ssize_t read_port(struct file *file, char __user *buf,
size_t count, loff_t *ppos)
{
unsigned long i = *ppos;
char __user *tmp = buf;
if (!access_ok(VERIFY_WRITE, buf, count))
- return -EFAULT;
+ return -EFAULT;
while (count-- > 0 && i < 65536) {
- if (__put_user(inb(i),tmp) < 0)
- return -EFAULT;
+ if (__put_user(inb(i), tmp) < 0)
+ return -EFAULT;
i++;
tmp++;
}
@@ -588,22 +589,22 @@ static ssize_t read_port(struct file * file, char __user * buf,
return tmp-buf;
}
-static ssize_t write_port(struct file * file, const char __user * buf,
+static ssize_t write_port(struct file *file, const char __user *buf,
size_t count, loff_t *ppos)
{
unsigned long i = *ppos;
const char __user * tmp = buf;
- if (!access_ok(VERIFY_READ,buf,count))
+ if (!access_ok(VERIFY_READ, buf, count))
return -EFAULT;
while (count-- > 0 && i < 65536) {
char c;
if (__get_user(c, tmp)) {
if (tmp > buf)
break;
- return -EFAULT;
+ return -EFAULT;
}
- outb(c,i);
+ outb(c, i);
i++;
tmp++;
}
@@ -612,13 +613,13 @@ static ssize_t write_port(struct file * file, const char __user * buf,
}
#endif
-static ssize_t read_null(struct file * file, char __user * buf,
+static ssize_t read_null(struct file *file, char __user *buf,
size_t count, loff_t *ppos)
{
return 0;
}
-static ssize_t write_null(struct file * file, const char __user * buf,
+static ssize_t write_null(struct file *file, const char __user *buf,
size_t count, loff_t *ppos)
{
return count;
@@ -630,13 +631,13 @@ static int pipe_to_null(struct pipe_inode_info *info, struct pipe_buffer *buf,
return sd->len;
}
-static ssize_t splice_write_null(struct pipe_inode_info *pipe,struct file *out,
+static ssize_t splice_write_null(struct pipe_inode_info *pipe, struct file *out,
loff_t *ppos, size_t len, unsigned int flags)
{
return splice_from_pipe(pipe, out, ppos, len, flags, pipe_to_null);
}
-static ssize_t read_zero(struct file * file, char __user * buf,
+static ssize_t read_zero(struct file *file, char __user *buf,
size_t count, loff_t *ppos)
{
size_t written;
@@ -667,7 +668,7 @@ static ssize_t read_zero(struct file * file, char __user * buf,
return written ? written : -EFAULT;
}
-static int mmap_zero(struct file * file, struct vm_area_struct * vma)
+static int mmap_zero(struct file *file, struct vm_area_struct *vma)
{
#ifndef CONFIG_MMU
return -ENOSYS;
@@ -677,7 +678,7 @@ static int mmap_zero(struct file * file, struct vm_area_struct * vma)
return 0;
}
-static ssize_t write_full(struct file * file, const char __user * buf,
+static ssize_t write_full(struct file *file, const char __user *buf,
size_t count, loff_t *ppos)
{
return -ENOSPC;
@@ -688,8 +689,7 @@ static ssize_t write_full(struct file * file, const char __user * buf,
* can fopen() both devices with "a" now. This was previously impossible.
* -- SRB.
*/
-
-static loff_t null_lseek(struct file * file, loff_t offset, int orig)
+static loff_t null_lseek(struct file *file, loff_t offset, int orig)
{
return file->f_pos = 0;
}
@@ -702,24 +702,31 @@ static loff_t null_lseek(struct file * file, loff_t offset, int orig)
* also note that seeking relative to the "end of file" isn't supported:
* it has no meaning, so it returns -EINVAL.
*/
-static loff_t memory_lseek(struct file * file, loff_t offset, int orig)
+static loff_t memory_lseek(struct file *file, loff_t offset, int orig)
{
loff_t ret;
mutex_lock(&file->f_path.dentry->d_inode->i_mutex);
switch (orig) {
- case 0:
- file->f_pos = offset;
- ret = file->f_pos;
- force_successful_syscall_return();
+ case SEEK_CUR:
+ offset += file->f_pos;
+ if ((unsigned long long)offset <
+ (unsigned long long)file->f_pos) {
+ ret = -EOVERFLOW;
break;
- case 1:
- file->f_pos += offset;
- ret = file->f_pos;
- force_successful_syscall_return();
+ }
+ case SEEK_SET:
+ /* to avoid userland mistaking f_pos=-9 as -EBADF=-9 */
+ if ((unsigned long long)offset >= ~0xFFFULL) {
+ ret = -EOVERFLOW;
break;
- default:
- ret = -EINVAL;
+ }
+ file->f_pos = offset;
+ ret = file->f_pos;
+ force_successful_syscall_return();
+ break;
+ default:
+ ret = -EINVAL;
}
mutex_unlock(&file->f_path.dentry->d_inode->i_mutex);
return ret;
@@ -803,7 +810,7 @@ static const struct file_operations oldmem_fops = {
};
#endif
-static ssize_t kmsg_write(struct file * file, const char __user * buf,
+static ssize_t kmsg_write(struct file *file, const char __user *buf,
size_t count, loff_t *ppos)
{
char *tmp;
@@ -825,7 +832,7 @@ static ssize_t kmsg_write(struct file * file, const char __user * buf,
}
static const struct file_operations kmsg_fops = {
- .write = kmsg_write,
+ .write = kmsg_write,
};
static const struct memdev {
@@ -876,7 +883,7 @@ static int memory_open(struct inode *inode, struct file *filp)
}
static const struct file_operations memory_fops = {
- .open = memory_open,
+ .open = memory_open,
};
static char *mem_devnode(struct device *dev, mode_t *mode)
@@ -897,7 +904,7 @@ static int __init chr_dev_init(void)
if (err)
return err;
- if (register_chrdev(MEM_MAJOR,"mem",&memory_fops))
+ if (register_chrdev(MEM_MAJOR, "mem", &memory_fops))
printk("unable to get major %d for memory devs\n", MEM_MAJOR);
mem_class = class_create(THIS_MODULE, "mem");