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path: root/drivers/char/mem.c
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Diffstat (limited to 'drivers/char/mem.c')
-rw-r--r--drivers/char/mem.c106
1 files changed, 50 insertions, 56 deletions
diff --git a/drivers/char/mem.c b/drivers/char/mem.c
index c6fa3bc2baa..917403fe10d 100644
--- a/drivers/char/mem.c
+++ b/drivers/char/mem.c
@@ -21,13 +21,12 @@
#include <linux/ptrace.h>
#include <linux/device.h>
#include <linux/highmem.h>
-#include <linux/crash_dump.h>
#include <linux/backing-dev.h>
-#include <linux/bootmem.h>
#include <linux/splice.h>
#include <linux/pfn.h>
#include <linux/export.h>
#include <linux/io.h>
+#include <linux/aio.h>
#include <asm/uaccess.h>
@@ -100,6 +99,9 @@ static ssize_t read_mem(struct file *file, char __user *buf,
ssize_t read, sz;
char *ptr;
+ if (p != *ppos)
+ return 0;
+
if (!valid_phys_addr_range(p, count))
return -EFAULT;
read = 0;
@@ -158,6 +160,9 @@ static ssize_t write_mem(struct file *file, const char __user *buf,
unsigned long copied;
void *ptr;
+ if (p != *ppos)
+ return -EFBIG;
+
if (!valid_phys_addr_range(p, count))
return -EFAULT;
@@ -356,40 +361,6 @@ static int mmap_kmem(struct file *file, struct vm_area_struct *vma)
}
#endif
-#ifdef CONFIG_CRASH_DUMP
-/*
- * Read memory corresponding to the old kernel.
- */
-static ssize_t read_oldmem(struct file *file, char __user *buf,
- size_t count, loff_t *ppos)
-{
- unsigned long pfn, offset;
- size_t read = 0, csize;
- int rc = 0;
-
- while (count) {
- pfn = *ppos / PAGE_SIZE;
- if (pfn > saved_max_pfn)
- return read;
-
- offset = (unsigned long)(*ppos % PAGE_SIZE);
- if (count > PAGE_SIZE - offset)
- csize = PAGE_SIZE - offset;
- else
- csize = count;
-
- rc = copy_oldmem_page(pfn, buf, csize, offset, 1);
- if (rc < 0)
- return rc;
- buf += csize;
- *ppos += csize;
- read += csize;
- count -= csize;
- }
- return read;
-}
-#endif
-
#ifdef CONFIG_DEVKMEM
/*
* This function reads the *virtual* memory as seen by the kernel.
@@ -399,7 +370,7 @@ static ssize_t read_kmem(struct file *file, char __user *buf,
{
unsigned long p = *ppos;
ssize_t low_count, read, sz;
- char * kbuf; /* k-addr because vread() takes vmlist_lock rwlock */
+ char *kbuf; /* k-addr because vread() takes vmlist_lock rwlock */
int err = 0;
read = 0;
@@ -527,7 +498,7 @@ static ssize_t write_kmem(struct file *file, const char __user *buf,
unsigned long p = *ppos;
ssize_t wrote = 0;
ssize_t virtr = 0;
- char * kbuf; /* k-addr because vwrite() takes vmlist_lock rwlock */
+ char *kbuf; /* k-addr because vwrite() takes vmlist_lock rwlock */
int err = 0;
if (p < (unsigned long) high_memory) {
@@ -595,7 +566,7 @@ 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;
+ const char __user *tmp = buf;
if (!access_ok(VERIFY_READ, buf, count))
return -EFAULT;
@@ -627,6 +598,18 @@ static ssize_t write_null(struct file *file, const char __user *buf,
return count;
}
+static ssize_t aio_read_null(struct kiocb *iocb, const struct iovec *iov,
+ unsigned long nr_segs, loff_t pos)
+{
+ return 0;
+}
+
+static ssize_t aio_write_null(struct kiocb *iocb, const struct iovec *iov,
+ unsigned long nr_segs, loff_t pos)
+{
+ return iov_length(iov, nr_segs);
+}
+
static int pipe_to_null(struct pipe_inode_info *info, struct pipe_buffer *buf,
struct splice_desc *sd)
{
@@ -670,6 +653,24 @@ static ssize_t read_zero(struct file *file, char __user *buf,
return written ? written : -EFAULT;
}
+static ssize_t aio_read_zero(struct kiocb *iocb, const struct iovec *iov,
+ unsigned long nr_segs, loff_t pos)
+{
+ size_t written = 0;
+ unsigned long i;
+ ssize_t ret;
+
+ for (i = 0; i < nr_segs; i++) {
+ ret = read_zero(iocb->ki_filp, iov[i].iov_base, iov[i].iov_len,
+ &pos);
+ if (ret < 0)
+ break;
+ written += ret;
+ }
+
+ return written ? written : -EFAULT;
+}
+
static int mmap_zero(struct file *file, struct vm_area_struct *vma)
{
#ifndef CONFIG_MMU
@@ -708,13 +709,13 @@ 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);
+ mutex_lock(&file_inode(file)->i_mutex);
switch (orig) {
case SEEK_CUR:
offset += file->f_pos;
case SEEK_SET:
/* to avoid userland mistaking f_pos=-9 as -EBADF=-9 */
- if ((unsigned long long)offset >= ~0xFFFULL) {
+ if (IS_ERR_VALUE((unsigned long long)offset)) {
ret = -EOVERFLOW;
break;
}
@@ -725,11 +726,11 @@ static loff_t memory_lseek(struct file *file, loff_t offset, int orig)
default:
ret = -EINVAL;
}
- mutex_unlock(&file->f_path.dentry->d_inode->i_mutex);
+ mutex_unlock(&file_inode(file)->i_mutex);
return ret;
}
-static int open_port(struct inode * inode, struct file * filp)
+static int open_port(struct inode *inode, struct file *filp)
{
return capable(CAP_SYS_RAWIO) ? 0 : -EPERM;
}
@@ -738,9 +739,9 @@ static int open_port(struct inode * inode, struct file * filp)
#define full_lseek null_lseek
#define write_zero write_null
#define read_full read_zero
+#define aio_write_zero aio_write_null
#define open_mem open_port
#define open_kmem open_mem
-#define open_oldmem open_mem
static const struct file_operations mem_fops = {
.llseek = memory_lseek,
@@ -766,6 +767,8 @@ static const struct file_operations null_fops = {
.llseek = null_lseek,
.read = read_null,
.write = write_null,
+ .aio_read = aio_read_null,
+ .aio_write = aio_write_null,
.splice_write = splice_write_null,
};
@@ -782,6 +785,8 @@ static const struct file_operations zero_fops = {
.llseek = zero_lseek,
.read = read_zero,
.write = write_zero,
+ .aio_read = aio_read_zero,
+ .aio_write = aio_write_zero,
.mmap = mmap_zero,
};
@@ -801,14 +806,6 @@ static const struct file_operations full_fops = {
.write = write_full,
};
-#ifdef CONFIG_CRASH_DUMP
-static const struct file_operations oldmem_fops = {
- .read = read_oldmem,
- .open = open_oldmem,
- .llseek = default_llseek,
-};
-#endif
-
static const struct memdev {
const char *name;
umode_t mode;
@@ -830,9 +827,6 @@ static const struct memdev {
#ifdef CONFIG_PRINTK
[11] = { "kmsg", 0644, &kmsg_fops, NULL },
#endif
-#ifdef CONFIG_CRASH_DUMP
- [12] = { "oldmem", 0, &oldmem_fops, NULL },
-#endif
};
static int memory_open(struct inode *inode, struct file *filp)
@@ -898,7 +892,7 @@ static int __init chr_dev_init(void)
continue;
/*
- * Create /dev/port?
+ * Create /dev/port?
*/
if ((minor == DEVPORT_MINOR) && !arch_has_dev_port())
continue;