1PMEM2_MAP_NEW(3) PMDK Programmer's Manual PMEM2_MAP_NEW(3)
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6 pmem2_map_new() - creates a mapping
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9 #include <libpmem2.h>
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11 struct pmem2_config;
12 struct pmem2_source;
13 struct pmem2_map;
14 int pmem2_map_new(struct pmem2_map **map_ptr, const struct pmem2_config *config,
15 const struct pmem2_source *source);
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18 The pmem2_map_new() function creates a new mapping in the virtual ad‐
19 dress space of the calling process. This function requires a configu‐
20 ration config of the mapping and the data source source.
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22 Optionally, the mapping can be created at the offset of the virtual
23 memory reservation set in the configuration config. See pmem2_con‐
24 fig_set_vm_reservation(3) for details.
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26 For a mapping to succeed, the config structure must have the granulari‐
27 ty parameter set to the appropriate level. See pmem2_config_set_re‐
28 quired_store_granularity(3) and libpmem2(7) for more details.
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30 If the pmem2_map_new() function succeeds in creating a new mapping it
31 instantiates a new *struct pmem2_map** object describing the mapping.
32 The pointer to this newly created object is stored in the user-provided
33 variable passed via the map_ptr pointer. If the mapping fails the
34 variable pointed by map_ptr will contain a NULL value and appropriate
35 error value will be returned. For a list of possible return values
36 please see RETURN VALUE.
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38 All struct pmem2_map objects created via the pmem2_map_new() function
39 have to be destroyed using the pmem2_map_delete() function. For de‐
40 tails please see pmem2_map_delete(3) manual page.
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43 The pmem2_map_new() function returns 0 on success or a negative error
44 code on failure.
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47 The pmem2_map_new() can fail with the following errors:
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49 • PMEM2_E_GRANULARITY_NOT_SET - the store granularity for the mapping
50 was not set in the provided config structure. Please see pmem2_con‐
51 fig_set_required_store_granularity(3) and libpmem2(7).
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53 • PMEM2_E_MAP_RANGE - offset + length is too big to represent it using
54 size_t data type
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56 • PMEM2_E_MAP_RANGE - end of the mapping (offset + length) is outside
57 of the file. The file is too small.
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59 • PMEM2_E_SOURCE_EMPTY - mapped file has size equal to 0.
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61 • PMEM2_E_MAPPING_EXISTS - if the object exists before the function
62 call. For details please see CreateFileMapping() manual pages.
63 (Windows only)
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65 • PMEM2_E_OFFSET_UNALIGNED - argument unaligned, offset is not a multi‐
66 ple of the alignment required for specific *source. Please see
67 pmem2_source_alignment(3).
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69 • PMEM2_E_LENGTH_UNALIGNED - argument unaligned, length is not a multi‐
70 ple of the alignment required for specific *source. Please see
71 pmem2_source_alignment(3).
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73 • PMEM2_E_SRC_DEVDAX_PRIVATE - device DAX mapped with MAP_PRIVATE.
74 (Linux only)
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76 • PMEM2_E_ADDRESS_UNALIGNED - when mapping device DAX to a virtual mem‐
77 ory reservation and the base mapping address (reservation address +
78 reservation offset) is not aligned to the device DAX granularity.
79 Please see pmem2_config_set_vm_reservation(3). (Linux only)
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81 • PMEM2_E_ADDRESS_UNALIGNED - when mapping to a virtual memory reserva‐
82 tion and the region for the mapping exceeds reservation size. Please
83 see pmem2_config_set_vm_reservation(3).
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85 • PMEM2_E_NOSUPP - when config-provided protection flags combination is
86 not supported.
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88 • PMEM2_E_NO_ACCESS - there is a conflict between mapping protection
89 and file opening mode.
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91 It can also return -EACCES, -EAGAIN, -EBADF, -ENFILE, -ENODEV, -ENOMEM,
92 -EPERM, -ETXTBSY from the underlying mmap(2) function. It is used with
93 and without MAP_ANONYMOUS.
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95 -EACCES may be returned only if the file descriptor points to an ap‐
96 pend-only file.
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98 It can also return all errors from the underlying pmem2_source_size()
99 and pmem2_source_alignment() functions.
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102 mmap(2), open(3), pmem2_config_set_required_store_granularity(3),
103 pmem2_source_alignment(3), pmem2_source_from_fd(3),
104 pmem2_source_size(3), pmem2_map_delete(3), pmem2_config_set_vm_reserva‐
105 tion(3), libpmem2(7) and <https://pmem.io>
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109PMDK - pmem2 API version 1.0 2022-05-24 PMEM2_MAP_NEW(3)