From patchwork Wed Jun 6 18:19:30 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Vivek Dasmohapatra X-Patchwork-Id: 27671 Received: (qmail 22021 invoked by alias); 6 Jun 2018 18:19:48 -0000 Mailing-List: contact libc-alpha-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Unsubscribe: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: libc-alpha-owner@sourceware.org Delivered-To: mailing list libc-alpha@sourceware.org Received: (qmail 21883 invoked by uid 89); 6 Jun 2018 18:19:44 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-26.9 required=5.0 tests=BAYES_00, GIT_PATCH_0, GIT_PATCH_1, GIT_PATCH_2, GIT_PATCH_3, RCVD_IN_DNSWL_NONE, SPF_HELO_PASS, SPF_PASS autolearn=ham version=3.3.2 spammy=H*r:902, secondary, reserved X-HELO: bhuna.collabora.co.uk From: =?UTF-8?q?Vivek=20Das=C2=A0Mohapatra?= To: libc-alpha@sourceware.org Subject: [RFC][PATCH v2 2/6] include/link.h: Update the link_map struct to allow proxies Date: Wed, 6 Jun 2018 18:19:30 +0000 Message-Id: <20180606181934.2480-3-vivek@collabora.com> In-Reply-To: <20180606181934.2480-1-vivek@collabora.com> References: <20180606181934.2480-1-vivek@collabora.com> We already have an l_real pointer, used for a similar purpose by the linker for copies of ld.so in secondary namespaces. Update its documentation and add a bitfield to indicate when link_map entry is a proxy. --- include/link.h | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/include/link.h b/include/link.h index 5924594548..c07eb35237 100644 --- a/include/link.h +++ b/include/link.h @@ -104,8 +104,9 @@ struct link_map They may change without notice. */ /* This is an element which is only ever different from a pointer to - the very same copy of this type for ld.so when it is used in more - than one namespace. */ + the very same copy of this type when: + - A shallow copy of ld.so is placed in namespaces other than LM_ID_BASE. + - An object is proxied into a namespace by dlmopen with RTLD_SHARED. */ struct link_map *l_real; /* Number of the namespace this link map belongs to. */ @@ -177,6 +178,7 @@ struct link_map unsigned int l_relocated:1; /* Nonzero if object's relocations done. */ unsigned int l_init_called:1; /* Nonzero if DT_INIT function called. */ unsigned int l_global:1; /* Nonzero if object in _dl_global_scope. */ + unsigned int l_proxy:1; /* Nonzero if object is a shallow copy. */ unsigned int l_reserved:2; /* Reserved for internal use. */ unsigned int l_phdr_allocated:1; /* Nonzero if the data structure pointed to by `l_phdr' is allocated. */