X-Git-Url: http://pilppa.org/gitweb/gitweb.cgi?a=blobdiff_plain;f=fs%2Fread_write.c;h=969a6d9c020ba01644578b04c86043b15e98b53a;hb=14800984706bf6936bbec5187f736e928be5c218;hp=1c177f29e1b72be0aa63f38496ed81727d01f653;hpb=6e5565f949af1322f8f3d3f43d044645ae448499;p=linux-2.6-omap-h63xx.git

diff --git a/fs/read_write.c b/fs/read_write.c
index 1c177f29e1b..969a6d9c020 100644
--- a/fs/read_write.c
+++ b/fs/read_write.c
@@ -31,57 +31,63 @@ const struct file_operations generic_ro_fops = {
 
 EXPORT_SYMBOL(generic_ro_fops);
 
-loff_t generic_file_llseek(struct file *file, loff_t offset, int origin)
+/**
+ * generic_file_llseek_unlocked - lockless generic llseek implementation
+ * @file:	file structure to seek on
+ * @offset:	file offset to seek to
+ * @origin:	type of seek
+ *
+ * Updates the file offset to the value specified by @offset and @origin.
+ * Locking must be provided by the caller.
+ */
+loff_t
+generic_file_llseek_unlocked(struct file *file, loff_t offset, int origin)
 {
-	long long retval;
 	struct inode *inode = file->f_mapping->host;
 
-	mutex_lock(&inode->i_mutex);
 	switch (origin) {
-		case SEEK_END:
-			offset += inode->i_size;
-			break;
-		case SEEK_CUR:
-			offset += file->f_pos;
+	case SEEK_END:
+		offset += inode->i_size;
+		break;
+	case SEEK_CUR:
+		offset += file->f_pos;
+		break;
 	}
-	retval = -EINVAL;
-	if (offset>=0 && offset<=inode->i_sb->s_maxbytes) {
-		if (offset != file->f_pos) {
-			file->f_pos = offset;
-			file->f_version = 0;
-		}
-		retval = offset;
+
+	if (offset < 0 || offset > inode->i_sb->s_maxbytes)
+		return -EINVAL;
+
+	/* Special lock needed here? */
+	if (offset != file->f_pos) {
+		file->f_pos = offset;
+		file->f_version = 0;
 	}
-	mutex_unlock(&inode->i_mutex);
-	return retval;
-}
 
-EXPORT_SYMBOL(generic_file_llseek);
+	return offset;
+}
+EXPORT_SYMBOL(generic_file_llseek_unlocked);
 
-loff_t remote_llseek(struct file *file, loff_t offset, int origin)
+/**
+ * generic_file_llseek - generic llseek implementation for regular files
+ * @file:	file structure to seek on
+ * @offset:	file offset to seek to
+ * @origin:	type of seek
+ *
+ * This is a generic implemenation of ->llseek useable for all normal local
+ * filesystems.  It just updates the file offset to the value specified by
+ * @offset and @origin under i_mutex.
+ */
+loff_t generic_file_llseek(struct file *file, loff_t offset, int origin)
 {
-	long long retval;
+	loff_t rval;
 
-	lock_kernel();
-	switch (origin) {
-		case SEEK_END:
-			offset += i_size_read(file->f_path.dentry->d_inode);
-			break;
-		case SEEK_CUR:
-			offset += file->f_pos;
-	}
-	retval = -EINVAL;
-	if (offset>=0 && offset<=file->f_path.dentry->d_inode->i_sb->s_maxbytes) {
-		if (offset != file->f_pos) {
-			file->f_pos = offset;
-			file->f_version = 0;
-		}
-		retval = offset;
-	}
-	unlock_kernel();
-	return retval;
+	mutex_lock(&file->f_dentry->d_inode->i_mutex);
+	rval = generic_file_llseek_unlocked(file, offset, origin);
+	mutex_unlock(&file->f_dentry->d_inode->i_mutex);
+
+	return rval;
 }
-EXPORT_SYMBOL(remote_llseek);
+EXPORT_SYMBOL(generic_file_llseek);
 
 loff_t no_llseek(struct file *file, loff_t offset, int origin)
 {
@@ -91,7 +97,7 @@ EXPORT_SYMBOL(no_llseek);
 
 loff_t default_llseek(struct file *file, loff_t offset, int origin)
 {
-	long long retval;
+	loff_t retval;
 
 	lock_kernel();
 	switch (origin) {
@@ -366,7 +372,6 @@ asmlinkage ssize_t sys_read(unsigned int fd, char __user * buf, size_t count)
 
 	return ret;
 }
-EXPORT_UNUSED_SYMBOL_GPL(sys_read); /* to be deleted for 2.6.25 */
 
 asmlinkage ssize_t sys_write(unsigned int fd, const char __user * buf, size_t count)
 {