Orangefs: Clean up error decoding.

Errors from the server need to be decoded. A bunch of code was imported from
the server to do this but much of it is convoluted and not even needed. The
result is better but still as convoluted as required by the protocol.
Signed-off-by: Martin Brandenburg <martin@omnibond.com>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>

fs/orangefs/pvfs2-utils.c

@@ -662,20 +662,45 @@ __u64 pvfs2_convert_time_field(void *time_ptr)
 	return pvfs2_time;
 }
 
-/* macro defined in include/pvfs2-types.h */
-DECLARE_ERRNO_MAPPING_AND_FN();
+/* The following is a very dirty hack that is now a permanent part of the
+ * PVFS2 protocol. See protocol.h for more error definitions. */
+
+/* The order matches include/pvfs2-types.h in the OrangeFS source. */
+static int PINT_errno_mapping[] = {
+        0, EPERM, ENOENT, EINTR, EIO, ENXIO, EBADF, EAGAIN, ENOMEM,
+        EFAULT, EBUSY, EEXIST, ENODEV, ENOTDIR, EISDIR, EINVAL, EMFILE,
+        EFBIG, ENOSPC, EROFS, EMLINK, EPIPE, EDEADLK, ENAMETOOLONG,
+        ENOLCK, ENOSYS, ENOTEMPTY, ELOOP, EWOULDBLOCK, ENOMSG, EUNATCH,
+        EBADR, EDEADLOCK, ENODATA, ETIME, ENONET, EREMOTE, ECOMM,
+        EPROTO, EBADMSG, EOVERFLOW, ERESTART, EMSGSIZE, EPROTOTYPE,
+        ENOPROTOOPT, EPROTONOSUPPORT, EOPNOTSUPP, EADDRINUSE,
+        EADDRNOTAVAIL, ENETDOWN, ENETUNREACH, ENETRESET, ENOBUFS,
+        ETIMEDOUT, ECONNREFUSED, EHOSTDOWN, EHOSTUNREACH, EALREADY,
+        EACCES, ECONNRESET, ERANGE
+};
 
 int pvfs2_normalize_to_errno(__s32 error_code)
 {
-	if (error_code > 0) {
+	/* Success */
+	if (error_code == 0) {
+		return 0;
+	/* This shouldn't ever happen. If it does it should be fixed on the
+	 * server. */
+	} else if (error_code > 0) {
 		gossip_err("pvfs2: error status receieved.\n");
 		gossip_err("pvfs2: assuming error code is inverted.\n");
 		error_code = -error_code;
 	}
 
-	/* convert any error codes that are in pvfs2 format */
-	if (IS_PVFS_NON_ERRNO_ERROR(-error_code)) {
-		if (PVFS_NON_ERRNO_ERROR_CODE(-error_code) == PVFS_ECANCEL) {
+	/* XXX: This is very bad since error codes from PVFS2 may not be
+	 * suitable for return into userspace. */
+
+	/* Convert PVFS2 error values into errno values suitable for return
+	 * from the kernel. */
+	if ((-error_code) & PVFS_NON_ERRNO_ERROR_BIT) {
+		if (((-error_code) &
+		    (PVFS_ERROR_NUMBER_BITS|PVFS_NON_ERRNO_ERROR_BIT|
+		    PVFS_ERROR_BIT)) == PVFS_ECANCEL) {
 			/*
 			 * cancellation error codes generally correspond to
 			 * a timeout from the client's perspective
@@ -683,12 +708,25 @@ int pvfs2_normalize_to_errno(__s32 error_code)
 			error_code = -ETIMEDOUT;
 		} else {
 			/* assume a default error code */
-			gossip_err("pvfs2: warning: got error code without errno equivalent: %d.\n",
-				   error_code);
+			gossip_err("pvfs2: warning: got error code without "
+			    "errno equivalent: %d.\n", error_code);
 			error_code = -EINVAL;
 		}
-	} else if (IS_PVFS_ERROR(-error_code)) {
-		error_code = -PVFS_ERROR_TO_ERRNO(-error_code);
+
+	/* Convert PVFS2 encoded errno values into regular errno values. */
+	} else if ((-error_code) & PVFS_ERROR_BIT) {
+		__u32 i;
+		i = (-error_code) & ~(PVFS_ERROR_BIT|PVFS_ERROR_CLASS_BITS);
+		if (i < sizeof PINT_errno_mapping/sizeof *PINT_errno_mapping)
+			error_code = -PINT_errno_mapping[i];
+		else
+			error_code = -EINVAL;
+
+	/* Only PVFS2 protocol error codes should ever come here. Otherwise
+	 * there is a bug somewhere. */
+	} else {
+		gossip_err("pvfs2: pvfs2_normalize_to_errno: got error code"
+		    "which is not from PVFS2.\n");
 	}
 	return error_code;
 }