From: Marc Dionne <marc.dionne@your-file-system.com>
Date: Mon, 6 Jul 2015 16:01:38 +0000 (-0300)
Subject: Linux 4.2: Changes in link operation APIs
X-Git-Tag: openafs-stable-1_8_0pre1~307
X-Git-Url: https://git.openafs.org/?p=openafs.git;a=commitdiff_plain;h=6c3ac6dc1ea865153a65b5c5c4f288617a3e6d0f

Linux 4.2: Changes in link operation APIs

The follow_link and put_link operations are revised.
Test for the new signature and adapt the code.

Change-Id: I2834589cbe36c41924ab0505e6ca4ecd797a57fd
Reviewed-on: http://gerrit.openafs.org/11928
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Jeffrey Altman <jaltman@your-file-system.com>
---

diff --git a/acinclude.m4 b/acinclude.m4
index 74fc776..f39237b 100644
--- a/acinclude.m4
+++ b/acinclude.m4
@@ -901,6 +901,16 @@ case $AFS_SYSNAME in *_linux* | *_umlinux*)
 		 LINUX_KBUILD_USES_EXTRA_CFLAGS
 		 LINUX_KERNEL_COMPILE_WORKS
 
+		 dnl Operation signature checks
+		 AC_CHECK_LINUX_OPERATION([inode_operations], [follow_link], [no_nameidata],
+					  [#include <linux/fs.h>],
+					  [const char *],
+					  [struct dentry *dentry, void **link_data])
+		 AC_CHECK_LINUX_OPERATION([inode_operations], [put_link], [no_nameidata],
+					  [#include <linux/fs.h>],
+					  [void],
+					  [struct inode *inode, void *link_data])
+
 		 dnl Check for header files
 		 AC_CHECK_LINUX_HEADER([config.h])
 		 AC_CHECK_LINUX_HEADER([completion.h])
diff --git a/src/afs/LINUX/osi_vnodeops.c b/src/afs/LINUX/osi_vnodeops.c
index 481ce87..6efc086 100644
--- a/src/afs/LINUX/osi_vnodeops.c
+++ b/src/afs/LINUX/osi_vnodeops.c
@@ -1902,14 +1902,22 @@ afs_linux_readlink(struct dentry *dp, char *target, int maxlen)
 /* afs_linux_follow_link
  * a file system dependent link following routine.
  */
+#if defined(HAVE_LINUX_INODE_OPERATIONS_FOLLOW_LINK_NO_NAMEIDATA)
+static const char *afs_linux_follow_link(struct dentry *dentry, void **link_data)
+#else
 static int afs_linux_follow_link(struct dentry *dentry, struct nameidata *nd)
+#endif
 {
     int code;
     char *name;
 
     name = kmalloc(PATH_MAX, GFP_NOFS);
     if (!name) {
+#if defined(HAVE_LINUX_INODE_OPERATIONS_FOLLOW_LINK_NO_NAMEIDATA)
+	return ERR_PTR(-EIO);
+#else
 	return -EIO;
+#endif
     }
 
     AFS_GLOCK();
@@ -1917,14 +1925,32 @@ static int afs_linux_follow_link(struct dentry *dentry, struct nameidata *nd)
     AFS_GUNLOCK();
 
     if (code < 0) {
+#if defined(HAVE_LINUX_INODE_OPERATIONS_FOLLOW_LINK_NO_NAMEIDATA)
+	return ERR_PTR(code);
+#else
 	return code;
+#endif
     }
 
     name[code] = '\0';
+#if defined(HAVE_LINUX_INODE_OPERATIONS_FOLLOW_LINK_NO_NAMEIDATA)
+    return *link_data = name;
+#else
     nd_set_link(nd, name);
     return 0;
+#endif
 }
 
+#if defined(HAVE_LINUX_INODE_OPERATIONS_PUT_LINK_NO_NAMEIDATA)
+static void
+afs_linux_put_link(struct inode *inode, void *link_data)
+{
+    char *name = link_data;
+
+    if (name && !IS_ERR(name))
+	kfree(name);
+}
+#else
 static void
 afs_linux_put_link(struct dentry *dentry, struct nameidata *nd)
 {
@@ -1933,6 +1959,7 @@ afs_linux_put_link(struct dentry *dentry, struct nameidata *nd)
     if (name && !IS_ERR(name))
 	kfree(name);
 }
+#endif /* HAVE_LINUX_INODE_OPERATIONS_PUT_LINK_NO_NAMEIDATA */
 
 #endif /* USABLE_KERNEL_PAGE_SYMLINK_CACHE */