diff options
author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /include/asm-m68k/shm.h |
Linux-2.6.12-rc2v2.6.12-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!
Diffstat (limited to 'include/asm-m68k/shm.h')
-rw-r--r-- | include/asm-m68k/shm.h | 32 |
1 files changed, 32 insertions, 0 deletions
diff --git a/include/asm-m68k/shm.h b/include/asm-m68k/shm.h new file mode 100644 index 00000000000..3fa2f368fc1 --- /dev/null +++ b/include/asm-m68k/shm.h @@ -0,0 +1,32 @@ +#ifndef _M68K_SHM_H +#define _M68K_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 /* _M68K_SHM_H */ |