X-Git-Url: http://git.osdn.net/view?a=blobdiff_plain;f=fs%2Fread_write.c;h=122a3846d9e14270a26952e92b25971257ebd82b;hb=46a1c2c7ae53de2a5676754b54a73c591a3951d2;hp=fd72b592aa1b4a1d96841abedc86da5a67c3535b;hpb=68d70d03f8f5bd10a0e7337210b13f536fd4aeb9;p=sagit-ice-cold%2Fkernel_xiaomi_msm8998.git

diff --git a/fs/read_write.c b/fs/read_write.c
index fd72b592aa1b..122a3846d9e1 100644
--- a/fs/read_write.c
+++ b/fs/read_write.c
@@ -41,8 +41,19 @@ static inline int unsigned_offsets(struct file *file)
 	return file->f_mode & FMODE_UNSIGNED_OFFSET;
 }
 
-static loff_t lseek_execute(struct file *file, struct inode *inode,
-		loff_t offset, loff_t maxsize)
+/**
+ * vfs_setpos - update the file offset for lseek
+ * @file:	file structure in question
+ * @offset:	file offset to seek to
+ * @maxsize:	maximum file size
+ *
+ * This is a low-level filesystem helper for updating the file offset to
+ * the value specified by @offset if the given offset is valid and it is
+ * not equal to the current file offset.
+ *
+ * Return the specified offset on success and -EINVAL on invalid offset.
+ */
+loff_t vfs_setpos(struct file *file, loff_t offset, loff_t maxsize)
 {
 	if (offset < 0 && !unsigned_offsets(file))
 		return -EINVAL;
@@ -55,6 +66,7 @@ static loff_t lseek_execute(struct file *file, struct inode *inode,
 	}
 	return offset;
 }
+EXPORT_SYMBOL(vfs_setpos);
 
 /**
  * generic_file_llseek_size - generic llseek implementation for regular files
@@ -76,8 +88,6 @@ loff_t
 generic_file_llseek_size(struct file *file, loff_t offset, int whence,
 		loff_t maxsize, loff_t eof)
 {
-	struct inode *inode = file->f_mapping->host;
-
 	switch (whence) {
 	case SEEK_END:
 		offset += eof;
@@ -97,8 +107,7 @@ generic_file_llseek_size(struct file *file, loff_t offset, int whence,
 		 * like SEEK_SET.
 		 */
 		spin_lock(&file->f_lock);
-		offset = lseek_execute(file, inode, file->f_pos + offset,
-				       maxsize);
+		offset = vfs_setpos(file, file->f_pos + offset, maxsize);
 		spin_unlock(&file->f_lock);
 		return offset;
 	case SEEK_DATA:
@@ -120,7 +129,7 @@ generic_file_llseek_size(struct file *file, loff_t offset, int whence,
 		break;
 	}
 
-	return lseek_execute(file, inode, offset, maxsize);
+	return vfs_setpos(file, offset, maxsize);
 }
 EXPORT_SYMBOL(generic_file_llseek_size);