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PMEM2_MAP_FROM_EXISTING(3) PMDK Programmer's Manual PMEM2_MAP_FROM_EXISTING(3)

NAME

pmem2_map_from_existing() - creates a pmem2_map object from an existing mapping

SYNOPSIS


#include <libpmem2.h>
int pmem2_map_from_existing(struct pmem2_map **map, const struct pmem2_source *src,
    void *addr, size_t len, enum pmem2_granularity gran);

    

DESCRIPTION

The pmem2_map_from_existing() returns a new *struct pmem2_map for mapping provided by the user. This function allows usage of libpmem2(7) API without pmem2_map_new(3) for mapping file. Mapping is defined by addr and len . You have to specify underlying file as a src, and define granularity of this mapping. See pmem2_config_set_required_store_granularity(3) and libpmem2**(7) for more details.

For the pmem2_map object created by the pmem2_map_from_existing(3) function, the pmem2_map_delete(3) will only destroy the object, but it won’t unmap the mapping this object describes.

RETURN VALUE

The pmem2_map_from_existing() function returns 0 when it succeeds or a negative error code on failure.

ERRORS

The pmem2_map_from_existing() can fail with the following errors:

PMEM2_E_MAPPING_EXISTS - when contiguous region (addr, addr + len) is all ready registered by libpmem2

It can also return -ENOMEM from the underlying malloc(2) function.

SEE ALSO

malloc(2), pmem2_map_delete(3), pmem2_map_new(3), pmem2_source_from_fd(3), libpmem2(7) and <http://pmem.io>
2020-10-16 PMDK - pmem2 API version 1.0