NAME

       pmem2_badblock_context_new(),   pmem2_badblock_context_delete()   -  allocate  and  free  a  context  for
       pmem2_badblock_next() and pmem2_badblock_clear() operations

SYNOPSIS

              #include <libpmem2.h>

              struct pmem2_source;
              struct pmem2_badblock_context;

              int pmem2_badblock_context_new(
                      struct pmem2_badblock_context **bbctx,
                      const struct pmem2_source *src);

              void pmem2_badblock_context_delete(
                      struct pmem2_badblock_context **bbctx);

DESCRIPTION

       The pmem2_badblock_context_new() function instantiates  a  new  (opaque)  bad  block  context  structure,
       pmem2_badblock_context,  which  is  used  to  read  and  clear  bad  blocks (by pmem2_badblock_next() and
       pmem2_badblock_clear()).  The function returns the bad block context through the pointer in *bbctx.

       New bad block context structure is initialized with values read from the source given as the first  argu‐
       ment (src).

       A  bad  block  is an uncorrectable media error - a part of a storage media that is either inaccessible or
       unwritable due to permanent physical damage.  In case of memory-mapped I/O, if a process tries to  access
       (read or write) the corrupted block, it will be terminated by the SIGBUS signal.

       The  pmem2_badblock_context_delete()  function  frees *bbctx returned by pmem2_badblock_context_new() and
       sets *bbctx to NULL.  If *bbctx is NULL, no operation is performed.

       It is not supported on Windows.

RETURN VALUE

       The pmem2_badblock_context_new() function returns 0 on success or a negative error code on failure.

       The pmem2_badblock_context_new() sets *bbctx to NULL on failure.

       The pmem2_badblock_context_delete() does not return any value.

ERRORS

       The pmem2_badblock_context_new() can fail with the following errors:

       • PMEM2_E_INVALID_FILE_TYPE - src is not a regular file nor a character device.

       • PMEM2_E_DAX_REGION_NOT_FOUND - cannot find a DAX region for the given src.

       • PMEM2_E_CANNOT_READ_BOUNDS - cannot read offset or size of the namespace of the given src.

       • PMEM2_E_NOSUPP - on Windows or when the OS does not support this functionality

       • -ENOMEM - out of memory

       • -errno - set by failing ndctl_new, while trying to create a new ndctl context.

       • -errno - set by failing fstat(2), while trying to validate the file descriptor of src.

       • -errno - set by failing realpath(3), while trying to get the canonicalized absolute sysfs  pathname  of
         DAX device given in src.

       • -errno - set by failing open(2), while trying to open the FSDAX device matching with the src.

       • -errno - set by failing read(2), while trying to read from the FSDAX device matching with the src.

       • -errno  -  set by failing ndctl_region_get_resource, while reading an offset of the region of the given
         src.

       • -errno - set by failing fiemap ioctl(2), while reading file extents of the given src.

SEE ALSO

       pmem2_badblock_next(3), pmem2_badblock_clear(3), libpmem2(7) and <https://pmem.io>