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>

2 files changed, 80 insertions, 264 deletions

diff --git a/fs/orangefs/protocol.h b/fs/orangefs/protocol.h
index cdbde64f8e39..b374c4b2009e 100644
--- a/fs/orangefs/protocol.h
+++ b/fs/orangefs/protocol.h
@@ -100,262 +100,40 @@ typedef __s32 PVFS_error;
 typedef __s64 PVFS_offset;
 
 #define PVFS2_SUPER_MAGIC 0x20030528
-#define PVFS_ERROR_BIT           (1 << 30)
-#define PVFS_NON_ERRNO_ERROR_BIT (1 << 29)
-#define IS_PVFS_ERROR(__error)   ((__error)&(PVFS_ERROR_BIT))
-#define IS_PVFS_NON_ERRNO_ERROR(__error)  \
-(((__error)&(PVFS_NON_ERRNO_ERROR_BIT)) && IS_PVFS_ERROR(__error))
-#define PVFS_ERROR_TO_ERRNO(__error) PVFS_get_errno_mapping(__error)
-
-/* 7 bits are used for the errno mapped error codes */
-#define PVFS_ERROR_CODE(__error) \
-((__error) & (__s32)(0x7f|PVFS_ERROR_BIT))
-#define PVFS_ERROR_CLASS(__error) \
-((__error) & ~((__s32)(0x7f|PVFS_ERROR_BIT|PVFS_NON_ERRNO_ERROR_BIT)))
-#define PVFS_NON_ERRNO_ERROR_CODE(__error) \
-((__error) & (__s32)(127|PVFS_ERROR_BIT|PVFS_NON_ERRNO_ERROR_BIT))
-
-/* PVFS2 error codes, compliments of asm/errno.h */
-#define PVFS_EPERM            E(1)	/* Operation not permitted */
-#define PVFS_ENOENT           E(2)	/* No such file or directory */
-#define PVFS_EINTR            E(3)	/* Interrupted system call */
-#define PVFS_EIO              E(4)	/* I/O error */
-#define PVFS_ENXIO            E(5)	/* No such device or address */
-#define PVFS_EBADF            E(6)	/* Bad file number */
-#define PVFS_EAGAIN           E(7)	/* Try again */
-#define PVFS_ENOMEM           E(8)	/* Out of memory */
-#define PVFS_EFAULT           E(9)	/* Bad address */
-#define PVFS_EBUSY           E(10)	/* Device or resource busy */
-#define PVFS_EEXIST          E(11)	/* File exists */
-#define PVFS_ENODEV          E(12)	/* No such device */
-#define PVFS_ENOTDIR         E(13)	/* Not a directory */
-#define PVFS_EISDIR          E(14)	/* Is a directory */
-#define PVFS_EINVAL          E(15)	/* Invalid argument */
-#define PVFS_EMFILE          E(16)	/* Too many open files */
-#define PVFS_EFBIG           E(17)	/* File too large */
-#define PVFS_ENOSPC          E(18)	/* No space left on device */
-#define PVFS_EROFS           E(19)	/* Read-only file system */
-#define PVFS_EMLINK          E(20)	/* Too many links */
-#define PVFS_EPIPE           E(21)	/* Broken pipe */
-#define PVFS_EDEADLK         E(22)	/* Resource deadlock would occur */
-#define PVFS_ENAMETOOLONG    E(23)	/* File name too long */
-#define PVFS_ENOLCK          E(24)	/* No record locks available */
-#define PVFS_ENOSYS          E(25)	/* Function not implemented */
-#define PVFS_ENOTEMPTY       E(26)	/* Directory not empty */
-					/*
-#define PVFS_ELOOP           E(27)	 * Too many symbolic links encountered
-					 */
-#define PVFS_EWOULDBLOCK     E(28)	/* Operation would block */
-#define PVFS_ENOMSG          E(29)	/* No message of desired type */
-#define PVFS_EUNATCH         E(30)	/* Protocol driver not attached */
-#define PVFS_EBADR           E(31)	/* Invalid request descriptor */
-#define PVFS_EDEADLOCK       E(32)
-#define PVFS_ENODATA         E(33)	/* No data available */
-#define PVFS_ETIME           E(34)	/* Timer expired */
-#define PVFS_ENONET          E(35)	/* Machine is not on the network */
-#define PVFS_EREMOTE         E(36)	/* Object is remote */
-#define PVFS_ECOMM           E(37)	/* Communication error on send */
-#define PVFS_EPROTO          E(38)	/* Protocol error */
-#define PVFS_EBADMSG         E(39)	/* Not a data message */
-					/*
-#define PVFS_EOVERFLOW       E(40)	 * Value too large for defined data
-					 * type
-					 */
-					/*
-#define PVFS_ERESTART        E(41)	 * Interrupted system call should be
-					 * restarted
-					 */
-#define PVFS_EMSGSIZE        E(42)	/* Message too long */
-#define PVFS_EPROTOTYPE      E(43)	/* Protocol wrong type for socket */
-#define PVFS_ENOPROTOOPT     E(44)	/* Protocol not available */
-#define PVFS_EPROTONOSUPPORT E(45)	/* Protocol not supported */
-					/*
-#define PVFS_EOPNOTSUPP      E(46)	 * Operation not supported on transport
-					 * endpoint
-					 */
-#define PVFS_EADDRINUSE      E(47)	/* Address already in use */
-#define PVFS_EADDRNOTAVAIL   E(48)	/* Cannot assign requested address */
-#define PVFS_ENETDOWN        E(49)	/* Network is down */
-#define PVFS_ENETUNREACH     E(50)	/* Network is unreachable */
-					/*
-#define PVFS_ENETRESET       E(51)	 * Network dropped connection because
-					 * of reset
-					 */
-#define PVFS_ENOBUFS         E(52)	/* No buffer space available */
-#define PVFS_ETIMEDOUT       E(53)	/* Connection timed out */
-#define PVFS_ECONNREFUSED    E(54)	/* Connection refused */
-#define PVFS_EHOSTDOWN       E(55)	/* Host is down */
-#define PVFS_EHOSTUNREACH    E(56)	/* No route to host */
-#define PVFS_EALREADY        E(57)	/* Operation already in progress */
-#define PVFS_EACCES          E(58)	/* Access not allowed */
-#define PVFS_ECONNRESET      E(59)	/* Connection reset by peer */
-#define PVFS_ERANGE          E(60)	/* Math out of range or buf too small */
-
-/***************** non-errno/pvfs2 specific error codes *****************/
-#define PVFS_ECANCEL    (1|(PVFS_NON_ERRNO_ERROR_BIT|PVFS_ERROR_BIT))
-#define PVFS_EDEVINIT   (2|(PVFS_NON_ERRNO_ERROR_BIT|PVFS_ERROR_BIT))
-#define PVFS_EDETAIL    (3|(PVFS_NON_ERRNO_ERROR_BIT|PVFS_ERROR_BIT))
-#define PVFS_EHOSTNTFD  (4|(PVFS_NON_ERRNO_ERROR_BIT|PVFS_ERROR_BIT))
-#define PVFS_EADDRNTFD  (5|(PVFS_NON_ERRNO_ERROR_BIT|PVFS_ERROR_BIT))
-#define PVFS_ENORECVR   (6|(PVFS_NON_ERRNO_ERROR_BIT|PVFS_ERROR_BIT))
-#define PVFS_ETRYAGAIN  (7|(PVFS_NON_ERRNO_ERROR_BIT|PVFS_ERROR_BIT))
-#define PVFS_ENOTPVFS   (8|(PVFS_NON_ERRNO_ERROR_BIT|PVFS_ERROR_BIT))
-#define PVFS_ESECURITY  (9|(PVFS_NON_ERRNO_ERROR_BIT|PVFS_ERROR_BIT))
 
-/*
- * NOTE: PLEASE DO NOT ARBITRARILY ADD NEW ERRNO ERROR CODES!
- *
- * IF YOU CHOOSE TO ADD A NEW ERROR CODE (DESPITE OUR PLEA), YOU ALSO
- * NEED TO INCREMENT PVFS_ERRNO MAX (BELOW) AND ADD A MAPPING TO A
- * UNIX ERRNO VALUE IN THE MACROS BELOW (USED IN
- * src/common/misc/errno-mapping.c and the kernel module)
- */
-#define PVFS_ERRNO_MAX          61
-
-#define PVFS_ERROR_BMI    (1 << 7)	/* BMI-specific error */
-#define PVFS_ERROR_TROVE  (2 << 7)	/* Trove-specific error */
-#define PVFS_ERROR_FLOW   (3 << 7)
-#define PVFS_ERROR_SM     (4 << 7)	/* state machine specific error */
-#define PVFS_ERROR_SCHED  (5 << 7)
-#define PVFS_ERROR_CLIENT (6 << 7)
-#define PVFS_ERROR_DEV    (7 << 7)	/* device file interaction */
-
-#define PVFS_ERROR_CLASS_BITS	\
-	(PVFS_ERROR_BMI    |	\
-	 PVFS_ERROR_TROVE  |	\
-	 PVFS_ERROR_FLOW   |	\
-	 PVFS_ERROR_SM     |	\
-	 PVFS_ERROR_SCHED  |	\
-	 PVFS_ERROR_CLIENT |	\
-	 PVFS_ERROR_DEV)
-
-#define DECLARE_ERRNO_MAPPING()                       \
-__s32 PINT_errno_mapping[PVFS_ERRNO_MAX + 1] = { \
-	0,     /* leave this one empty */                 \
-	EPERM, /* 1 */                                    \
-	ENOENT,                                           \
-	EINTR,                                            \
-	EIO,                                              \
-	ENXIO,                                            \
-	EBADF,                                            \
-	EAGAIN,                                           \
-	ENOMEM,                                           \
-	EFAULT,                                           \
-	EBUSY, /* 10 */                                   \
-	EEXIST,                                           \
-	ENODEV,                                           \
-	ENOTDIR,                                          \
-	EISDIR,                                           \
-	EINVAL,                                           \
-	EMFILE,                                           \
-	EFBIG,                                            \
-	ENOSPC,                                           \
-	EROFS,                                            \
-	EMLINK, /* 20 */                                  \
-	EPIPE,                                            \
-	EDEADLK,                                          \
-	ENAMETOOLONG,                                     \
-	ENOLCK,                                           \
-	ENOSYS,                                           \
-	ENOTEMPTY,                                        \
-	ELOOP,                                            \
-	EWOULDBLOCK,                                      \
-	ENOMSG,                                           \
-	EUNATCH, /* 30 */                                 \
-	EBADR,                                            \
-	EDEADLOCK,                                        \
-	ENODATA,                                          \
-	ETIME,                                            \
-	ENONET,                                           \
-	EREMOTE,                                          \
-	ECOMM,                                            \
-	EPROTO,                                           \
-	EBADMSG,                                          \
-	EOVERFLOW, /* 40 */                               \
-	ERESTART,                                         \
-	EMSGSIZE,                                         \
-	EPROTOTYPE,                                       \
-	ENOPROTOOPT,                                      \
-	EPROTONOSUPPORT,                                  \
-	EOPNOTSUPP,                                       \
-	EADDRINUSE,                                       \
-	EADDRNOTAVAIL,                                    \
-	ENETDOWN,                                         \
-	ENETUNREACH, /* 50 */                             \
-	ENETRESET,                                        \
-	ENOBUFS,                                          \
-	ETIMEDOUT,                                        \
-	ECONNREFUSED,                                     \
-	EHOSTDOWN,                                        \
-	EHOSTUNREACH,                                     \
-	EALREADY,                                         \
-	EACCES,                                           \
-	ECONNRESET,   /* 59 */                            \
-	ERANGE,                                           \
-	0         /* PVFS_ERRNO_MAX */                    \
-};                                                    \
-const char *PINT_non_errno_strerror_mapping[] = {     \
-	"Success", /* 0 */                                \
-	"Operation cancelled (possibly due to timeout)",  \
-	"Device initialization failed",                   \
-	"Detailed per-server errors are available",       \
-	"Unknown host",                                   \
-	"No address associated with name",                \
-	"Unknown server error",                           \
-	"Host name lookup failure",                       \
-	"Path contains non-PVFS elements",                \
-	"Security error",                                 \
-};                                                    \
-__s32 PINT_non_errno_mapping[] = {               \
-	0,     /* leave this one empty */                 \
-	PVFS_ECANCEL,   /* 1 */                           \
-	PVFS_EDEVINIT,  /* 2 */                           \
-	PVFS_EDETAIL,   /* 3 */                           \
-	PVFS_EHOSTNTFD, /* 4 */                           \
-	PVFS_EADDRNTFD, /* 5 */                           \
-	PVFS_ENORECVR,  /* 6 */                           \
-	PVFS_ETRYAGAIN, /* 7 */                           \
-	PVFS_ENOTPVFS,  /* 8 */                           \
-	PVFS_ESECURITY, /* 9 */                           \
-}
+/* PVFS2 error codes are a signed 32-bit integer. Error codes are negative, but
+ * the sign is stripped before decoding. */
 
-/*
- *   NOTE: PVFS_get_errno_mapping will convert a PVFS_ERROR_CODE to an
- *   errno value.  If the error code is a pvfs2 specific error code
- *   (i.e. a PVFS_NON_ERRNO_ERROR_CODE), PVFS_get_errno_mapping will
- *   return an index into the PINT_non_errno_strerror_mapping array which
- *   can be used for getting the pvfs2 specific strerror message given
- *   the error code.  if the value is not a recognized error code, the
- *   passed in value will be returned unchanged.
- */
-#define DECLARE_ERRNO_MAPPING_AND_FN()					\
-extern __s32 PINT_errno_mapping[];					\
-extern __s32 PINT_non_errno_mapping[];				\
-extern const char *PINT_non_errno_strerror_mapping[];			\
-static __s32 PVFS_get_errno_mapping(__s32 error)			\
-{									\
-	__s32 ret = error, mask = 0;				\
-	__s32 positive = ((error > -1) ? 1 : 0);			\
-	if (IS_PVFS_NON_ERRNO_ERROR((positive ? error : -error))) {	\
-		mask = (PVFS_NON_ERRNO_ERROR_BIT |			\
-			PVFS_ERROR_BIT |				\
-			PVFS_ERROR_CLASS_BITS);				\
-		ret = PVFS_NON_ERRNO_ERROR_CODE(((positive ?		\
-						     error :		\
-						     abs(error))) &	\
-						 ~mask);		\
-	}								\
-	else if (IS_PVFS_ERROR((positive ? error : -error))) {		\
-		mask = (PVFS_ERROR_BIT |				\
-			PVFS_ERROR_CLASS_BITS);				\
-		ret = PINT_errno_mapping[PVFS_ERROR_CODE(((positive ?	\
-								error :	\
-								abs(error))) & \
-							  ~mask)];	\
-	}								\
-	return ret;							\
-}									\
-DECLARE_ERRNO_MAPPING()
+/* Bit 31 is not used since it is the sign. */
+
+/* Bit 30 specifies that this is a PVFS2 error. A PVFS2 error is either an
+ * encoded errno value or a PVFS2 protocol error. */
+#define PVFS_ERROR_BIT (1 << 30)
+
+/* Bit 29 specifies that this is a PVFS2 protocol error and not an encoded
+ * errno value. */
+#define PVFS_NON_ERRNO_ERROR_BIT (1 << 29)
+
+/* Bits 9, 8, and 7 specify the error class, which encodes the section of
+ * server code the error originated in for logging purposes. It is not used
+ * in the kernel except to be masked out. */
+#define PVFS_ERROR_CLASS_BITS 0x380
+
+/* Bits 6 - 0 are reserved for the actual error code. */
+#define PVFS_ERROR_NUMBER_BITS 0x7f
+
+/* Encoded errno values are decoded by PINT_errno_mapping in pvfs2-utils.c. */
+
+/* Our own PVFS2 protocol error codes. */
+#define PVFS_ECANCEL    (1|PVFS_NON_ERRNO_ERROR_BIT|PVFS_ERROR_BIT)
+#define PVFS_EDEVINIT   (2|PVFS_NON_ERRNO_ERROR_BIT|PVFS_ERROR_BIT)
+#define PVFS_EDETAIL    (3|PVFS_NON_ERRNO_ERROR_BIT|PVFS_ERROR_BIT)
+#define PVFS_EHOSTNTFD  (4|PVFS_NON_ERRNO_ERROR_BIT|PVFS_ERROR_BIT)
+#define PVFS_EADDRNTFD  (5|PVFS_NON_ERRNO_ERROR_BIT|PVFS_ERROR_BIT)
+#define PVFS_ENORECVR   (6|PVFS_NON_ERRNO_ERROR_BIT|PVFS_ERROR_BIT)
+#define PVFS_ETRYAGAIN  (7|PVFS_NON_ERRNO_ERROR_BIT|PVFS_ERROR_BIT)
+#define PVFS_ENOTPVFS   (8|PVFS_NON_ERRNO_ERROR_BIT|PVFS_ERROR_BIT)
+#define PVFS_ESECURITY  (9|PVFS_NON_ERRNO_ERROR_BIT|PVFS_ERROR_BIT)
 
 /* permission bits */
 #define PVFS_O_EXECUTE (1 << 0)
diff --git a/fs/orangefs/pvfs2-utils.c b/fs/orangefs/pvfs2-utils.c
index 834e06674d0a..086ebbb36570 100644
--- a/fs/orangefs/pvfs2-utils.c
+++ b/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;
 }