From: Paolo 'Blaisorblade' Giarrusso <[email protected]>
Generalize _calc_vm_trans macro for subsequent use in remap_file_pages
protection support.
Signed-off-by: Paolo 'Blaisorblade' Giarrusso <[email protected]>
---
include/linux/bitops.h | 10 ++++++++++
include/linux/mman.h | 25 ++++++++-----------------
2 files changed, 18 insertions(+), 17 deletions(-)
diff --git a/include/linux/bitops.h b/include/linux/bitops.h
index 5d1eabc..f25aa43 100644
--- a/include/linux/bitops.h
+++ b/include/linux/bitops.h
@@ -3,6 +3,16 @@ #define _LINUX_BITOPS_H
#include <asm/types.h>
/*
+ * Optimisation macro. It is equivalent to:
+ * (x & bit1) ? bit2 : 0
+ * but this version is faster.
+ * ("bit1" and "bit2" must be single bits)
+ */
+#define bitmask_trans(x, bit1, bit2) \
+ ((bit1) <= (bit2) ? ((x) & (bit1)) * ((bit2) / (bit1)) \
+ : ((x) & (bit1)) / ((bit1) / (bit2)))
+
+/*
* Include this here because some architectures need generic_ffs/fls in
* scope
*/
diff --git a/include/linux/mman.h b/include/linux/mman.h
index 87920a0..6ac90be 100644
--- a/include/linux/mman.h
+++ b/include/linux/mman.h
@@ -14,6 +14,7 @@ #ifdef __KERNEL__
#include <linux/mm.h>
#include <asm/atomic.h>
+#include <linux/bitops.h>
extern int sysctl_overcommit_memory;
extern int sysctl_overcommit_ratio;
@@ -34,24 +35,14 @@ static inline void vm_unacct_memory(long
}
/*
- * Optimisation macro. It is equivalent to:
- * (x & bit1) ? bit2 : 0
- * but this version is faster.
- * ("bit1" and "bit2" must be single bits)
- */
-#define _calc_vm_trans(x, bit1, bit2) \
- ((bit1) <= (bit2) ? ((x) & (bit1)) * ((bit2) / (bit1)) \
- : ((x) & (bit1)) / ((bit1) / (bit2)))
-
-/*
* Combine the mmap "prot" argument into "vm_flags" used internally.
*/
static inline unsigned long
calc_vm_prot_bits(unsigned long prot)
{
- return _calc_vm_trans(prot, PROT_READ, VM_READ ) |
- _calc_vm_trans(prot, PROT_WRITE, VM_WRITE) |
- _calc_vm_trans(prot, PROT_EXEC, VM_EXEC );
+ return bitmask_trans(prot, PROT_READ, VM_READ ) |
+ bitmask_trans(prot, PROT_WRITE, VM_WRITE) |
+ bitmask_trans(prot, PROT_EXEC, VM_EXEC );
}
/*
@@ -60,10 +51,10 @@ calc_vm_prot_bits(unsigned long prot)
static inline unsigned long
calc_vm_flag_bits(unsigned long flags)
{
- return _calc_vm_trans(flags, MAP_GROWSDOWN, VM_GROWSDOWN ) |
- _calc_vm_trans(flags, MAP_DENYWRITE, VM_DENYWRITE ) |
- _calc_vm_trans(flags, MAP_EXECUTABLE, VM_EXECUTABLE) |
- _calc_vm_trans(flags, MAP_LOCKED, VM_LOCKED );
+ return bitmask_trans(flags, MAP_GROWSDOWN, VM_GROWSDOWN ) |
+ bitmask_trans(flags, MAP_DENYWRITE, VM_DENYWRITE ) |
+ bitmask_trans(flags, MAP_EXECUTABLE, VM_EXECUTABLE) |
+ bitmask_trans(flags, MAP_LOCKED, VM_LOCKED );
}
#endif /* __KERNEL__ */
#endif /* _LINUX_MMAN_H */
Chiacchiera con i tuoi amici in tempo reale!
http://it.yahoo.com/mail_it/foot/*http://it.messenger.yahoo.com