File libxc-bitmap-long.patch of Package xen.21904

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File libxc-bitmap-long.patch of Package xen.21904

From: Olaf Hering <olaf@aepfle.de>
Date: Wed, 9 Dec 2020 16:40:00 +0100
Subject: bitmap long

tools: add API to work with sevaral bits at once

Introduce new API to test if a fixed number of bits is clear or set,
and clear or set them all at once.

The caller has to make sure the input bitnumber is a multiply of BITS_PER_LONG.

This API avoids the loop over each bit in a known range just to see
if all of them are either clear or set.

Signed-off-by: Olaf Hering <olaf@aepfle.de>
---
 tools/libxc/xc_bitops.h | 25 +++++++++++++++++++++++++
 1 file changed, 25 insertions(+)

Index: xen-4.14.0-testing/tools/libxc/xc_bitops.h
===================================================================
--- xen-4.14.0-testing.orig/tools/libxc/xc_bitops.h
+++ xen-4.14.0-testing/tools/libxc/xc_bitops.h
@@ -79,4 +79,29 @@ static inline void bitmap_or(void *_dst,
         dst[i] |= other[i];
 }
 
+static inline int test_bit_long_set(unsigned long nr_base, const void *_addr)
+{
+    const unsigned long *addr = _addr;
+    unsigned long val = addr[nr_base / BITS_PER_LONG];
+    return val == ~0;
+}
+
+static inline int test_bit_long_clear(unsigned long nr_base, const void *_addr)
+{
+    const unsigned long *addr = _addr;
+    unsigned long val = addr[nr_base / BITS_PER_LONG];
+    return val == 0;
+}
+
+static inline void clear_bit_long(unsigned long nr_base, void *_addr)
+{
+    unsigned long *addr = _addr;
+    addr[nr_base / BITS_PER_LONG] = 0;
+}
+
+static inline void set_bit_long(unsigned long nr_base, void *_addr)
+{
+    unsigned long *addr = _addr;
+    addr[nr_base / BITS_PER_LONG] = ~0;
+}
 #endif  /* XC_BITOPS_H */

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File libxc-bitmap-long.patch of Package xen.21904

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