rsm_memseg_import_puRemoteMShared Memory Library Frsm_memseg_import_putv(3RSM)NAME
rsm_memseg_import_putv, rsm_memseg_import_getv - write to a segment
using a list of I/O requests
SYNOPSIS
cc [ flag... ] file... -lrsm [ library... ]
#include <rsmapi.h>
int rsm_memseg_import_putv(rsm_scat_gath_t *sg_io);
int rsm_memseg_import_getv(rsm_scat_gath_t *sg_io);
DESCRIPTION
The rsm_memseg_import_putv() and rsm_memseg_import_getv() functions
provide for using a list of I/O requests rather than a single source
and destination address as is done for thersm_memseg_import_put(3RSM)
and rsm_memseg_import_get(3RSM) functions.
The I/O vector component of the scatter-gather list (sg_io), allows
specifying local virtual addresses or local_memory_handles. When a
local address range is used repeatedly, it is efficient to use a handle
because allocated system resources (that is, locked down local memory)
are maintained until the handle is freed. The supporting functions for
handles are rsm_create_localmemory_handle(3RSM) and rsm_free_localmem‐
ory_handle(3RSM).
Virtual addresses or handles may be gathered into the vector for writ‐
ing to a single remote segment, or a read from a single remote segment
may be scattered to the vector of virtual addresses or handles.
Implicit mapping is supported for the scatter-gather type of access.
The attributes of the extension library for the specific interconnect
are used to determine whether mapping is necessary before any scatter-
gather access. If mapping of the imported segment is a prerequisite for
scatter-gather access and the mapping has not already been performed,
an implicit mapping is performed for the imported segment. The I/O for
the vector is then initiated.
I/O for the entire vector is initiated before returning. The barrier
mode attribute of the import segment determines if the I/O has com‐
pleted before the function returns. A barrier mode attribute setting
of IMPLICIT guarantees that the transfer of data is completed in the
order as entered in the I/O vector. An implicit barrier open and close
surrounds each list entry. If an error is detected, I/O for the vector
is terminated and the function returns immediately. The residual count
indicates the number of entries for which the I/O either did not com‐
plete or was not initiated.
The number of entries in the I/O vector component of the scatter-gather
list is specified in the io_request_count field of the rsm_scat_gath_t
pointed to by sg_io. The io_request_count is valid if greater than 0
and less than or equal to RSM_MAX_SGIOREQS. If io_request_count is not
in the valid range, rsm_memseg_import_putv() and rsm_mem‐
seg_import_getv() returns RSMERR_BAD_SGIO.
Optionally, the scatter-gather list allows support for an implicit sig‐
nal post after the I/O for the entire vector has completed. This alle‐
viates the need to do an explicit signal post after ever I/O transfer
operation. The means of enabling the implicit signal post involves set‐
ting the flags field within the scatter-gather list to
RSM_IMPLICIT_SIGPOST. The flags field may also be set to
RSM_SIG_POST_NO_ACCUMULATE, which will be passed on to the signal post
operation when RSM_IMPLICIT_SIGPOST is set.
RETURN VALUES
Upon successful completion, these functions return 0. Otherwise, an
error value is returned to indicate the error.
ERRORS
The rsm_memseg_import_putv() and rsm_memseg_import_getv() functions can
return the following errors:
RSMERR_BAD_SGIO Invalid scatter-gather structure
pointer.
RSMERR_BAD_SEG_HNDL Invalid segment handle.
RSMERR_BAD_CTLR_HNDL Invalid controller handle.
RSMERR_BAD_OFFSET Invalid offset.
RSMERR_BAD_LENGTH Invalid length.
RSMERR_BAD_ADDR Bad address.
RSMERR_INSUFFICIENT_RESOURCES Insufficient resources.
RSMERR_INTERRUPTED The operation was interrupted by a sig‐
nal.
RSMERR_PERM_DENIED Permission denied.
RSMERR_BARRIER_FAILURE I/O completion error.
RSMERR_REMOTE_NODE_UNREACHABLE Remote node not reachable.
ATTRIBUTES
See attributes(5) for descriptions of the following attributes:
┌─────────────────────────────┬─────────────────────────────┐
│ ATTRIBUTE TYPE │ ATTRIBUTE VALUE │
├─────────────────────────────┼─────────────────────────────┤
│Interface Stability │Evolving │
├─────────────────────────────┼─────────────────────────────┤
│MT-Level │MT-Safe │
└─────────────────────────────┴─────────────────────────────┘
SEE ALSOrsm_create_localmemory_handle(3RSM), rsm_free_localmemory_handle(3RSM),
attributes(5)SunOS 5.10 12 Nov 2001 rsm_memseg_import_putv(3RSM)
