static int
do_volop(struct fssync_state * state, afs_int32 command, SYNC_response * res)
{
afs_int32 code;
SYNC_PROTO_BUF_DECL(res_buf);
SYNC_response res_l;
if (!res) {
res = &res_l;
res->payload.len = SYNC_PROTO_MAX_LEN;
res->payload.buf = res_buf;
}
fprintf(stderr, "calling FSYNC_VolOp with command code %d (%s)\n",
command, FSYNC_com2string(command));
code = FSYNC_VolOp(state->vop->volume,
state->vop->partName,
command,
state->reason,
res);
debug_response(code, res);
VDisconnectFS();
return 0;
}
/* Try to detect if the fileserver is DAFS, and if so, re-exec as the
* DAFS-enabled fssync-debug (dafssync_debug). If we fail to detect or
* exec, just try to proceed anyway as if the server is not DAFS */
static void
dafs_prolog(void)
{
SYNC_response res;
SYNC_PROTO_BUF_DECL(res_buf);
afs_int32 code;
char *dfssd;
res.payload.len = SYNC_PROTO_MAX_LEN;
res.payload.buf = res_buf;
/* LISTVOLUMES is a no-op; we just want to get the response header flags
* to see if the server reports itself as DAFS or not */
code = FSYNC_VolOp(0, NULL, FSYNC_VOL_LISTVOLUMES, FSYNC_WHATEVER, &res);
if (code) {
/* probably failed to contact the fileserver; later code will provide
* some warning/error indication */
return;
}
if (!(res.hdr.flags & SYNC_FLAG_DAFS_EXTENSIONS)) {
/* fileserver is not DAFS, so we don't need to do anything */
return;
}
dfssd = afs_exec_alt(fssd_argc, fssd_argv, "da", NULL);
fprintf(stderr, "\n*** server asserted demand attach extensions, but we failed\n"
"*** to exec a DAFS-enabled fssync-debug '%s' (errno=%d);\n"
"*** attempting to proceed without it.\n\n", dfssd, errno);
free(dfssd);
}
/* No lock needed. Only the volserver will call this, and only one transaction
* can have a given volume (volid/partition pair) in use at a time
*/
void
VPurgeVolume(Error * ec, Volume * vp)
{
struct DiskPartition64 *tpartp = vp->partition;
char purgePath[MAXPATHLEN];
/* so VCheckDetach doesn't try to update the volume header and
* dump spurious errors into the logs */
V_inUse(vp) = 0;
/* N.B. it's important here to use the partition pointed to by the
* volume header. This routine can, under some circumstances, be called
* when two volumes with the same id exist on different partitions.
*/
(void)afs_snprintf(purgePath, sizeof purgePath, "%s/%s",
VPartitionPath(vp->partition),
VolumeExternalName(V_id(vp)));
PurgeIndex_r(vp, vLarge);
PurgeIndex_r(vp, vSmall);
PurgeHeader_r(vp);
unlink(purgePath);
/*
* Call the fileserver to break all call backs for that volume
*/
FSYNC_VolOp(V_id(vp), tpartp->name, FSYNC_VOL_BREAKCBKS, 0, NULL);
}
/**
* perform an asynchronous volume group scan.
*
* @param[in] partition vice partition string
* @param[in] reason FSSYNC reason code
*
* @note if partition is NULL, all vice partitions will be scanned.
*
* @return operation status
* @retval SYNC_OK success
*/
afs_int32
FSYNC_VGCScan(char * partition, int reason)
{
int command;
if (partition == NULL) {
command = FSYNC_VG_SCAN_ALL;
partition = "";
} else {
command = FSYNC_VG_SCAN;
}
return FSYNC_VolOp(0, partition, command, reason, NULL);
}
/**
* query the volume group cache.
*
* @param[in] part vice partition path
* @param[in] volid volume id
* @param[out] qry query response object
* @param[out] res SYNC response message
*
* @return operation status
* @retval SYNC_OK success
*/
afs_int32
FSYNC_VGCQuery(char * part,
VolumeId volid,
FSSYNC_VGQry_response_t * qry,
SYNC_response *res)
{
SYNC_response lres;
if (!res) {
res = &lres;
}
res->hdr.response_len = sizeof(res->hdr);
res->payload.buf = qry;
res->payload.len = sizeof(*qry);
return FSYNC_VolOp(volid, part, FSYNC_VG_QUERY, 0, res);
}
static int
do_volop(struct state * state, afs_int32 command, SYNC_response * res)
{
afs_int32 code;
SYNC_PROTO_BUF_DECL(res_buf);
SYNC_response res_l;
if (!res) {
res = &res_l;
res->payload.len = SYNC_PROTO_MAX_LEN;
res->payload.buf = res_buf;
}
fprintf(stderr, "calling FSYNC_VolOp with command code %d (%s)\n",
command, command_code_to_string(command));
code = FSYNC_VolOp(state->vop->volume,
state->vop->partName,
command,
state->reason,
res);
switch (code) {
case SYNC_OK:
case SYNC_DENIED:
break;
default:
fprintf(stderr, "possible sync protocol error. return code was %d\n", code);
}
fprintf(stderr, "FSYNC_VolOp returned %d (%s)\n", code, response_code_to_string(code));
fprintf(stderr, "protocol response code was %d (%s)\n",
res->hdr.response, response_code_to_string(res->hdr.response));
fprintf(stderr, "protocol reason code was %d (%s)\n",
res->hdr.reason, reason_code_to_string(res->hdr.reason));
VDisconnectFS();
}
/**
* verify that the fileserver still thinks we have a volume checked out.
*
* In DAFS, a non-fileserver program accesses a volume by checking it out from
* the fileserver (FSYNC_VOL_OFF or FSYNC_VOL_NEEDVOLUME), and then locks the
* volume. There is a possibility that the fileserver crashes or restarts for
* some reason between volume checkout and locking; if this happens, the
* fileserver could attach the volume before we had a chance to lock it. This
* function serves to detect if this has happened; it must be called after
* volume checkout and locking to make sure the fileserver still thinks we
* have the volume. (If it doesn't, we should try to check it out again.)
*
* @param[in] volume volume ID
* @param[in] partition partition name string
* @param[in] command the command that was used to checkout the volume
* @param[in] reason the reason code used to checkout the volume
*
* @return operation status
* @retval SYNC_OK the fileserver could not have attached the volume since
* it was checked out (either it thinks it is still checked
* out, or it doesn't know about the volume)
* @retval SYNC_DENIED fileserver may have restarted since checkout; checkout
* should be reattempted
* @retval SYNC_COM_ERROR internal/fatal error
*/
afs_int32
FSYNC_VerifyCheckout(VolumeId volume, char * partition,
afs_int32 command, afs_int32 reason)
{
SYNC_response res;
FSSYNC_VolOp_info vop;
afs_int32 code;
afs_int32 pid;
res.hdr.response_len = sizeof(res.hdr);
res.payload.buf = &vop;
res.payload.len = sizeof(vop);
code = FSYNC_VolOp(volume, partition, FSYNC_VOL_QUERY_VOP, FSYNC_WHATEVER, &res);
if (code != SYNC_OK) {
if (res.hdr.reason == FSYNC_NO_PENDING_VOL_OP) {
Log("FSYNC_VerifyCheckout: fileserver claims no vop for vol %lu "
"part %s; fileserver may have restarted since checkout\n",
afs_printable_uint32_lu(volume), partition);
return SYNC_DENIED;
}
if (res.hdr.reason == FSYNC_UNKNOWN_VOLID ||
res.hdr.reason == FSYNC_WRONG_PART) {
/* if the fileserver does not know about this volume on this
* partition, there's no way it could have attached it, so we're
* fine */
return SYNC_OK;
}
Log("FSYNC_VerifyCheckout: FSYNC_VOL_QUERY_VOP failed for vol %lu "
"part %s with code %ld reason %ld\n",
afs_printable_uint32_lu(volume), partition,
afs_printable_int32_ld(code),
afs_printable_int32_ld(res.hdr.reason));
return SYNC_COM_ERROR;
}
pid = getpid();
/* Check if the current vol op is us. Checking pid is probably enough, but
* be a little bit paranoid. We could also probably check tid, but I'm not
* completely confident of its reliability on all platforms (on pthread
* envs, we coerce a pthread_t to an afs_int32, which is not guaranteed
* to mean anything significant). */
if (vop.com.programType == programType && vop.com.pid == pid &&
vop.com.command == command && vop.com.reason == reason) {
/* looks like the current pending vol op is the same one as the one
* with which we checked it out. success. */
return SYNC_OK;
}
Log("FSYNC_VerifyCheckout: vop for vol %lu part %s does not match "
"expectations (got pt %ld pid %ld cmd %ld reason %ld, but expected "
"pt %ld pid %ld cmd %ld reason %ld); fileserver may have restarted "
"since checkout\n", afs_printable_uint32_lu(volume), partition,
afs_printable_int32_ld(vop.com.programType),
afs_printable_int32_ld(vop.com.pid),
afs_printable_int32_ld(vop.com.command),
afs_printable_int32_ld(vop.com.reason),
afs_printable_int32_ld(programType),
afs_printable_int32_ld(pid),
afs_printable_int32_ld(command),
afs_printable_int32_ld(reason));
return SYNC_DENIED;
}
