parisc: Convert MAP_TYPE to cover 4 bits on parisc
On parisc we want to be as much as possible compatible to the major architectures like x86. Those architectures have MAP_TYPE defined as 0x0f which covers MAP_SHARED and MAP_PRIVATE and leaves two more bits unused. In contrast, on parisc we have MAP_TYPE defined to 0x03 which covers MAP_SHARED and MAP_PRIVATE only. But we don't have the 2 bits free as x86. Usually that's not a problem, but during the discussions for pmem+dax support the idea came up to use the two remaining bits of MAP_TYPE (on x86 and others) for the new MAP_DIRECT and MAP_SYNC flags. One requirement is, that an old kernel should correctly handle MAP_DIRECT and MAP_SYNC and fail on those if set. This only works if MAP_TYPE has 4 bits. Even though the pmem+dax people now choosed another solution via MAP_SHARED_VALIDATE, let's still proceed to be more compatible to x86 by adding two more bits for future usage. Signed-off-by: Helge Deller <deller@gmx.de> Signed-off-by: John David Anglin <dave.anglin@bell.net>
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#define MAP_SHARED 0x01 /* Share changes */
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#define MAP_SHARED 0x01 /* Share changes */
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#define MAP_PRIVATE 0x02 /* Changes are private */
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#define MAP_PRIVATE 0x02 /* Changes are private */
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#define MAP_SHARED_VALIDATE 0x03 /* share + validate extension flags */
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#define MAP_SHARED_VALIDATE 0x03 /* share + validate extension flags */
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#define MAP_TYPE 0x03 /* Mask for type of mapping */
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#define MAP_TYPE 0x2b /* Mask for type of mapping, includes bits 0x08 and 0x20 */
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#define MAP_FIXED 0x04 /* Interpret addr exactly */
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#define MAP_FIXED 0x04 /* Interpret addr exactly */
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#define MAP_ANONYMOUS 0x10 /* don't use a file */
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#define MAP_ANONYMOUS 0x10 /* don't use a file */
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