#include <linux/vfs.h>
#include <linux/mutex.h>
#include <linux/exportfs.h>
+#include <linux/writeback.h>
+#include <linux/buffer_head.h>
#include <asm/uaccess.h>
return PTR_ERR(s);
s->s_flags = MS_NOUSER;
- s->s_maxbytes = ~0ULL;
+ s->s_maxbytes = MAX_LFS_FILESIZE;
s->s_blocksize = PAGE_SIZE;
s->s_blocksize_bits = PAGE_SHIFT;
s->s_magic = magic;
const void *from, size_t available)
{
loff_t pos = *ppos;
+ size_t ret;
+
if (pos < 0)
return -EINVAL;
- if (pos >= available)
+ if (pos >= available || !count)
return 0;
if (count > available - pos)
count = available - pos;
- if (copy_to_user(to, from + pos, count))
+ ret = copy_to_user(to, from + pos, count);
+ if (ret == count)
return -EFAULT;
+ count -= ret;
*ppos = pos + count;
return count;
}
if (copy_from_user(attr->set_buf, buf, size))
goto out;
- ret = len; /* claim we got the whole input */
attr->set_buf[size] = '\0';
val = simple_strtol(attr->set_buf, NULL, 0);
- attr->set(attr->data, val);
+ ret = attr->set(attr->data, val);
+ if (ret == 0)
+ ret = len; /* on success, claim we got the whole input */
out:
mutex_unlock(&attr->mutex);
return ret;
}
EXPORT_SYMBOL_GPL(generic_fh_to_parent);
+int simple_fsync(struct file *file, struct dentry *dentry, int datasync)
+{
+ struct writeback_control wbc = {
+ .sync_mode = WB_SYNC_ALL,
+ .nr_to_write = 0, /* metadata-only; caller takes care of data */
+ };
+ struct inode *inode = dentry->d_inode;
+ int err;
+ int ret;
+
+ ret = sync_mapping_buffers(inode->i_mapping);
+ if (!(inode->i_state & I_DIRTY))
+ return ret;
+ if (datasync && !(inode->i_state & I_DIRTY_DATASYNC))
+ return ret;
+
+ err = sync_inode(inode, &wbc);
+ if (ret == 0)
+ ret = err;
+ return ret;
+}
+EXPORT_SYMBOL(simple_fsync);
+
EXPORT_SYMBOL(dcache_dir_close);
EXPORT_SYMBOL(dcache_dir_lseek);
EXPORT_SYMBOL(dcache_dir_open);