android_kernel_motorola_sm6225/include/asm-h8300/shm.h
Linus Torvalds 1da177e4c3 Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!
2005-04-16 15:20:36 -07:00

32 lines
1 KiB
C

#ifndef _H8300_SHM_H
#define _H8300_SHM_H
#include <linux/config.h>
/* format of page table entries that correspond to shared memory pages
currently out in swap space (see also mm/swap.c):
bits 0-1 (PAGE_PRESENT) is = 0
bits 8..2 (SWP_TYPE) are = SHM_SWP_TYPE
bits 31..9 are used like this:
bits 15..9 (SHM_ID) the id of the shared memory segment
bits 30..16 (SHM_IDX) the index of the page within the shared memory segment
(actually only bits 25..16 get used since SHMMAX is so low)
bit 31 (SHM_READ_ONLY) flag whether the page belongs to a read-only attach
*/
/* on the m68k both bits 0 and 1 must be zero */
/* format on the sun3 is similar, but bits 30, 31 are set to zero and all
others are reduced by 2. --m */
#ifndef CONFIG_SUN3
#define SHM_ID_SHIFT 9
#else
#define SHM_ID_SHIFT 7
#endif
#define _SHM_ID_BITS 7
#define SHM_ID_MASK ((1<<_SHM_ID_BITS)-1)
#define SHM_IDX_SHIFT (SHM_ID_SHIFT+_SHM_ID_BITS)
#define _SHM_IDX_BITS 15
#define SHM_IDX_MASK ((1<<_SHM_IDX_BITS)-1)
#endif /* _H8300_SHM_H */