LU-8056 llite: inode_operations interface changed in 4.5

Linux kernel 4.5 replaced follow_link() with get_link()
while put_link() is removed.
This patch handles the API change.

Linux-commit:6b2553918d8b4e6de9853fd6315bec7271a2e592
Linux-commit:fceef393a538134f03b778c5d2519e670269342f

Signed-off-by: Li Dongyang <dongyang.li@anu.edu.au>
Change-Id: Ia9b8c9b855ed5ab7a428a370074b8801e34d3f99
Reviewed-on: http://review.whamcloud.com/20224
Tested-by: Jenkins
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: James Simmons <uja.ornl@yahoo.com>
Reviewed-by: Niu Yawei <yawei.niu@intel.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>

diff --git a/lustre/autoconf/lustre-core.m4 b/lustre/autoconf/lustre-core.m4
index 1b924f2..365727e 100644 (file)
--- a/lustre/autoconf/lustre-core.m4
+++ b/lustre/autoconf/lustre-core.m4
@@ -2125,6 +2125,25 @@ inode_lock, [
 ]) # LC_HAVE_INODE_LOCK
 
 #
+# LC_HAVE_IOP_GET_LINK
+#
+# 4.5 vfs replaced iop->follow_link with
+# iop->get_link
+#
+AC_DEFUN([LC_HAVE_IOP_GET_LINK], [
+LB_CHECK_COMPILE([if 'iop' has 'get_link'],
+inode_ops_get_link, [
+       #include <linux/fs.h>
+],[
+       struct inode_operations iop;
+       iop.get_link = NULL;
+],[
+       AC_DEFINE(HAVE_IOP_GET_LINK, 1,
+               [have iop get_link])
+])
+]) # LC_HAVE_IOP_GET_LINK
+
+#
 # LC_PROG_LINUX
 #
 # Lustre linux kernel checks
@@ -2302,6 +2321,7 @@ AC_DEFUN([LC_PROG_LINUX], [
 
        # 4.5
        LC_HAVE_INODE_LOCK
+       LC_HAVE_IOP_GET_LINK
 
        #
        AS_IF([test "x$enable_server" != xno], [

diff --git a/lustre/llite/dcache.c b/lustre/llite/dcache.c
index fa0e7aa..cee5ae3 100644 (file)
--- a/lustre/llite/dcache.c
+++ b/lustre/llite/dcache.c
@@ -320,7 +320,11 @@ static int ll_revalidate_dentry(struct dentry *dentry,
                return 1;
 
        /* Symlink - always valid as long as the dentry was found */
+#ifdef HAVE_IOP_GET_LINK
+       if (dentry->d_inode && dentry->d_inode->i_op->get_link)
+#else
        if (dentry->d_inode && dentry->d_inode->i_op->follow_link)
+#endif
                return 1;
 
        /*

diff --git a/lustre/llite/symlink.c b/lustre/llite/symlink.c
index e635037..70577ce 100644 (file)
--- a/lustre/llite/symlink.c
+++ b/lustre/llite/symlink.c
@@ -122,6 +122,20 @@ failed:
 }
 
 #ifdef HAVE_SYMLINK_OPS_USE_NAMEIDATA
+static void ll_put_link(struct dentry *dentry,
+                       struct nameidata *nd, void *cookie)
+#else
+# ifdef HAVE_IOP_GET_LINK
+static void ll_put_link(void *cookie)
+# else
+static void ll_put_link(struct inode *unused, void *cookie)
+# endif
+#endif
+{
+       ptlrpc_req_finished(cookie);
+}
+
+#ifdef HAVE_SYMLINK_OPS_USE_NAMEIDATA
 static void *ll_follow_link(struct dentry *dentry, struct nameidata *nd)
 {
        struct inode *inode = dentry->d_inode;
@@ -156,6 +170,34 @@ static void *ll_follow_link(struct dentry *dentry, struct nameidata *nd)
        RETURN(request);
 }
 #else
+# ifdef HAVE_IOP_GET_LINK
+static const char *ll_get_link(struct dentry *dentry,
+                              struct inode *inode,
+                              struct delayed_call *done)
+{
+       struct ptlrpc_request *request;
+       char *symname = NULL;
+       int rc;
+
+       ENTRY;
+       CDEBUG(D_VFSTRACE, "VFS Op\n");
+       if (!dentry)
+               RETURN(ERR_PTR(-ECHILD));
+       ll_inode_size_lock(inode);
+       rc = ll_readlink_internal(inode, &request, &symname);
+       ll_inode_size_unlock(inode);
+       if (rc < 0) {
+               ptlrpc_req_finished(request);
+               return ERR_PTR(rc);
+       }
+
+       /* symname may contain a pointer to the request message buffer,
+        * we delay request releasing then.
+        */
+       set_delayed_call(done, ll_put_link, request);
+       RETURN(symname);
+}
+# else
 static const char *ll_follow_link(struct dentry *dentry, void **cookie)
 {
        struct inode *inode = d_inode(dentry);
@@ -179,22 +221,18 @@ static const char *ll_follow_link(struct dentry *dentry, void **cookie)
        *cookie = request;
        RETURN(symname);
 }
+# endif /* HAVE_IOP_GET_LINK */
 #endif /* HAVE_SYMLINK_OPS_USE_NAMEIDATA */
 
-#ifdef HAVE_SYMLINK_OPS_USE_NAMEIDATA
-static void ll_put_link(struct dentry *dentry, struct nameidata *nd, void *cookie)
-#else
-static void ll_put_link(struct inode *unused, void *cookie)
-#endif
-{
-       ptlrpc_req_finished(cookie);
-}
-
 struct inode_operations ll_fast_symlink_inode_operations = {
        .readlink       = generic_readlink,
        .setattr        = ll_setattr,
+#ifdef HAVE_IOP_GET_LINK
+       .get_link       = ll_get_link,
+#else
        .follow_link    = ll_follow_link,
        .put_link       = ll_put_link,
+#endif
        .getattr        = ll_getattr,
        .permission     = ll_inode_permission,
        .setxattr       = ll_setxattr,