+21
−27
Loading
UAPI: ndctl: Fix g++-unsupported initialisation in headers
The following code in the linux/ndctl header file:
static inline const char *nvdimm_bus_cmd_name(unsigned cmd)
{
static const char * const names[] = {
[ND_CMD_ARS_CAP] = "ars_cap",
[ND_CMD_ARS_START] = "ars_start",
[ND_CMD_ARS_STATUS] = "ars_status",
[ND_CMD_CLEAR_ERROR] = "clear_error",
[ND_CMD_CALL] = "cmd_call",
};
if (cmd < ARRAY_SIZE(names) && names[cmd])
return names[cmd];
return "unknown";
}
is broken in a number of ways:
(1) ARRAY_SIZE() is not generally defined.
(2) g++ does not support "non-trivial" array initialisers fully yet.
(3) Every file that calls this function will acquire a copy of names[].
The same goes for nvdimm_cmd_name().
Fix all three by converting to a switch statement where each case returns a
string. That way if cmd is a constant, the compiler can trivially reduce it
and, if not, the compiler can use a shared lookup table if it thinks that is
more efficient.
A better way would be to remove these functions and their arrays from the
header entirely.
Signed-off-by: 
David Howells <dhowells@redhat.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>