ANDROID: Add optional __get xattr method paired to __vfs_getxattr
Add an optional __get xattr method that would be called, if set, only
in __vfs_getxattr instead of the regular get xattr method.
Signed-off-by: Mark Salyzyn <salyzyn@google.com>
Bug: 133515582
Bug: 136124883
Bug: 129319403
Change-Id: If9f6cf3e0d964e77af769244bb1e8f6aee4f4445
diff --git a/fs/xattr.c b/fs/xattr.c
index 3e5d157..35ead9b 100644
--- a/fs/xattr.c
+++ b/fs/xattr.c
@@ -307,6 +307,9 @@
handler = xattr_resolve_name(inode, &name);
if (IS_ERR(handler))
return PTR_ERR(handler);
+ if (unlikely(handler->__get))
+ return handler->__get(handler, dentry, inode, name, value,
+ size);
if (!handler->get)
return -EOPNOTSUPP;
return handler->get(handler, dentry, inode, name, value, size);
@@ -318,6 +321,7 @@
{
struct inode *inode = dentry->d_inode;
int error;
+ const struct xattr_handler *handler;
error = xattr_permission(inode, name, MAY_READ);
if (error)
@@ -340,7 +344,12 @@
return ret;
}
nolsm:
- return __vfs_getxattr(dentry, inode, name, value, size);
+ handler = xattr_resolve_name(inode, &name);
+ if (IS_ERR(handler))
+ return PTR_ERR(handler);
+ if (!handler->get)
+ return -EOPNOTSUPP;
+ return handler->get(handler, dentry, inode, name, value, size);
}
EXPORT_SYMBOL_GPL(vfs_getxattr);
diff --git a/include/linux/xattr.h b/include/linux/xattr.h
index d70f77a4..7f538d2 100644
--- a/include/linux/xattr.h
+++ b/include/linux/xattr.h
@@ -30,10 +30,13 @@
const char *prefix;
int flags; /* fs private flags */
bool (*list)(struct dentry *dentry);
- int (*get)(const struct xattr_handler *, struct dentry *dentry,
+ int (*get)(const struct xattr_handler *handler, struct dentry *dentry,
struct inode *inode, const char *name, void *buffer,
size_t size);
- int (*set)(const struct xattr_handler *, struct dentry *dentry,
+ int (*__get)(const struct xattr_handler *handler, struct dentry *dentry,
+ struct inode *inode, const char *name, void *buffer,
+ size_t size);
+ int (*set)(const struct xattr_handler *handler, struct dentry *dentry,
struct inode *inode, const char *name, const void *buffer,
size_t size, int flags);
};
