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.

Reviewed-on: http://gerrit.openafs.org/11928
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Jeffrey Altman <jaltman@your-file-system.com>
(cherry picked from commit 6c3ac6dc1ea865153a65b5c5c4f288617a3e6d0f)

Change-Id: I779fe8a29ec75a5db545b5d370927b810c1165c9
Reviewed-on: http://gerrit.openafs.org/11951
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Benjamin Kaduk <kaduk@mit.edu>
Reviewed-by: Stephan Wiesand <stephan.wiesand@desy.de>

diff --git a/acinclude.m4 b/acinclude.m4
index 935fd00..af56ea4 100644 (file)
--- a/acinclude.m4
+++ b/acinclude.m4
@@ -837,6 +837,16 @@ 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 a878eb4..3c0cb33 100644 (file)
--- a/src/afs/LINUX/osi_vnodeops.c
+++ b/src/afs/LINUX/osi_vnodeops.c
@@ -1896,14 +1896,22 @@ 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();
@@ -1911,14 +1919,32 @@ 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)
 {
@@ -1927,6 +1953,7 @@ 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 */