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-rw-r--r--include/asm-mips64/shmparam.h58
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diff --git a/include/asm-mips64/shmparam.h b/include/asm-mips64/shmparam.h
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+++ b/include/asm-mips64/shmparam.h
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+/* $Id$
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * XXX These are obviously wrong for an 64-bit OS, let's see how we divide
+ * the address space later ...
+ */
+#ifndef _ASM_SHMPARAM_H
+#define _ASM_SHMPARAM_H
+
+/* address range for shared memory attaches if no address passed to shmat() */
+#define SHM_RANGE_START 0x50000000
+#define SHM_RANGE_END 0x60000000
+
+/*
+ * Format of a swap-entry for shared memory pages currently out in
+ * swap space (see also mm/swap.c).
+ *
+ * SWP_TYPE = SHM_SWP_TYPE
+ * SWP_OFFSET is used as follows:
+ *
+ * bits 0..6 : id of shared memory segment page belongs to (SHM_ID)
+ * bits 7..21: index of page within shared memory segment (SHM_IDX)
+ * (actually fewer bits get used since SHMMAX is so low)
+ */
+
+/*
+ * Keep _SHM_ID_BITS as low as possible since SHMMNI depends on it and
+ * there is a static array of size SHMMNI.
+ */
+#define _SHM_ID_BITS 7
+#define SHM_ID_MASK ((1<<_SHM_ID_BITS)-1)
+
+#define SHM_IDX_SHIFT (_SHM_ID_BITS)
+#define _SHM_IDX_BITS 15
+#define SHM_IDX_MASK ((1<<_SHM_IDX_BITS)-1)
+
+/*
+ * _SHM_ID_BITS + _SHM_IDX_BITS must be <= 24 on the i386 and
+ * SHMMAX <= (PAGE_SIZE << _SHM_IDX_BITS).
+ */
+
+#define SHMMAX 0x2000000 /* max shared seg size (bytes) */
+/* Try not to change the default shipped SHMMAX - people rely on it */
+
+#define SHMMIN 1 /* really PAGE_SIZE */ /* min shared seg size (bytes) */
+#define SHMMNI (1<<_SHM_ID_BITS) /* max num of segs system wide */
+#define SHMALL /* max shm system wide (pages) */ \
+ (1<<(_SHM_IDX_BITS+_SHM_ID_BITS))
+/*
+ * This constant is very large but the ABI in it's wisdom says ...
+ */
+#define SHMLBA 0x40000 /* attach addr a multiple of this */
+#define SHMSEG SHMMNI /* max shared segs per process */
+
+#endif /* _ASM_SHMPARAM_H */