/*
* capabilities for /dev/zero
* - permits private mappings, "copies" are taken of the source of zeros
+ * - no writeback happens
*/
static struct backing_dev_info zero_bdi = {
.name = "char/mem",
- .capabilities = BDI_CAP_MAP_COPY,
+ .capabilities = BDI_CAP_MAP_COPY | BDI_CAP_NO_ACCT_AND_WRITEBACK,
};
static const struct file_operations full_fops = {
static const struct file_operations oldmem_fops = {
.read = read_oldmem,
.open = open_oldmem,
+ .llseek = default_llseek,
};
#endif
static const struct file_operations kmsg_fops = {
.write = kmsg_write,
+ .llseek = noop_llseek,
};
static const struct memdev {
if (dev->dev_info)
filp->f_mapping->backing_dev_info = dev->dev_info;
+ /* Is /dev/mem or /dev/kmem ? */
+ if (dev->dev_info == &directly_mappable_cdev_bdi)
+ filp->f_mode |= FMODE_UNSIGNED_OFFSET;
+
if (dev->fops->open)
return dev->fops->open(inode, filp);
static const struct file_operations memory_fops = {
.open = memory_open,
+ .llseek = noop_llseek,
};
static char *mem_devnode(struct device *dev, mode_t *mode)