NFS: Add a client-side function to display NFS file handles
For debugging, introduce a simplistic function to print NFS file
handles on the system console. The main function is hooked into the
dprintk debugging facility, but you can directly call the helper,
_nfs_display_fhandle(), if you want to print a handle unconditionally.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
diff --git a/fs/nfs/inode.c b/fs/nfs/inode.c
index 6c66259..99a4f52 100644
--- a/fs/nfs/inode.c
+++ b/fs/nfs/inode.c
@@ -1046,6 +1046,51 @@
}
/**
+ * _nfs_display_fhandle - display an NFS file handle on the console
+ *
+ * @fh: file handle to display
+ * @caption: display caption
+ *
+ * For debugging only.
+ */
+#ifdef RPC_DEBUG
+void _nfs_display_fhandle(const struct nfs_fh *fh, const char *caption)
+{
+ unsigned short i;
+
+ if (fh->size == 0 || fh == NULL) {
+ printk(KERN_DEFAULT "%s at %p is empty\n", caption, fh);
+ return;
+ }
+
+ printk(KERN_DEFAULT "%s at %p is %u bytes:\n", caption, fh, fh->size);
+ for (i = 0; i < fh->size; i += 16) {
+ __be32 *pos = (__be32 *)&fh->data[i];
+
+ switch ((fh->size - i - 1) >> 2) {
+ case 0:
+ printk(KERN_DEFAULT " %08x\n",
+ be32_to_cpup(pos));
+ break;
+ case 1:
+ printk(KERN_DEFAULT " %08x %08x\n",
+ be32_to_cpup(pos), be32_to_cpup(pos + 1));
+ break;
+ case 2:
+ printk(KERN_DEFAULT " %08x %08x %08x\n",
+ be32_to_cpup(pos), be32_to_cpup(pos + 1),
+ be32_to_cpup(pos + 2));
+ break;
+ default:
+ printk(KERN_DEFAULT " %08x %08x %08x %08x\n",
+ be32_to_cpup(pos), be32_to_cpup(pos + 1),
+ be32_to_cpup(pos + 2), be32_to_cpup(pos + 3));
+ }
+ }
+}
+#endif
+
+/**
* nfs_inode_attrs_need_update - check if the inode attributes need updating
* @inode - pointer to inode
* @fattr - attributes
diff --git a/include/linux/nfs_fs.h b/include/linux/nfs_fs.h
index 8c29950..c07a7576 100644
--- a/include/linux/nfs_fs.h
+++ b/include/linux/nfs_fs.h
@@ -395,6 +395,20 @@
kfree(fh);
}
+#ifdef RPC_DEBUG
+extern void _nfs_display_fhandle(const struct nfs_fh *fh, const char *caption);
+#define nfs_display_fhandle(fh, caption) \
+ do { \
+ if (unlikely(nfs_debug & NFSDBG_FACILITY)) \
+ _nfs_display_fhandle(fh, caption); \
+ } while (0)
+#else
+static inline void nfs_display_fhandle(const struct nfs_fh *fh,
+ const char *caption)
+{
+}
+#endif
+
/*
* linux/fs/nfs/nfsroot.c
*/