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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /arch/parisc/include/asm/checksum.h
Initial import
Diffstat (limited to 'arch/parisc/include/asm/checksum.h')
-rw-r--r--arch/parisc/include/asm/checksum.h210
1 files changed, 210 insertions, 0 deletions
diff --git a/arch/parisc/include/asm/checksum.h b/arch/parisc/include/asm/checksum.h
new file mode 100644
index 000000000..c84b2fcb1
--- /dev/null
+++ b/arch/parisc/include/asm/checksum.h
@@ -0,0 +1,210 @@
+#ifndef _PARISC_CHECKSUM_H
+#define _PARISC_CHECKSUM_H
+
+#include <linux/in6.h>
+
+/*
+ * computes the checksum of a memory block at buff, length len,
+ * and adds in "sum" (32-bit)
+ *
+ * returns a 32-bit number suitable for feeding into itself
+ * or csum_tcpudp_magic
+ *
+ * this function must be called with even lengths, except
+ * for the last fragment, which may be odd
+ *
+ * it's best to have buff aligned on a 32-bit boundary
+ */
+extern __wsum csum_partial(const void *, int, __wsum);
+
+/*
+ * The same as csum_partial, but copies from src while it checksums.
+ *
+ * Here even more important to align src and dst on a 32-bit (or even
+ * better 64-bit) boundary
+ */
+extern __wsum csum_partial_copy_nocheck(const void *, void *, int, __wsum);
+
+/*
+ * this is a new version of the above that records errors it finds in *errp,
+ * but continues and zeros the rest of the buffer.
+ */
+extern __wsum csum_partial_copy_from_user(const void __user *src,
+ void *dst, int len, __wsum sum, int *errp);
+
+/*
+ * Optimized for IP headers, which always checksum on 4 octet boundaries.
+ *
+ * Written by Randolph Chung <tausq@debian.org>, and then mucked with by
+ * LaMont Jones <lamont@debian.org>
+ */
+static inline __sum16 ip_fast_csum(const void *iph, unsigned int ihl)
+{
+ unsigned int sum;
+
+ __asm__ __volatile__ (
+" ldws,ma 4(%1), %0\n"
+" addib,<= -4, %2, 2f\n"
+"\n"
+" ldws 4(%1), %%r20\n"
+" ldws 8(%1), %%r21\n"
+" add %0, %%r20, %0\n"
+" ldws,ma 12(%1), %%r19\n"
+" addc %0, %%r21, %0\n"
+" addc %0, %%r19, %0\n"
+"1: ldws,ma 4(%1), %%r19\n"
+" addib,< 0, %2, 1b\n"
+" addc %0, %%r19, %0\n"
+"\n"
+" extru %0, 31, 16, %%r20\n"
+" extru %0, 15, 16, %%r21\n"
+" addc %%r20, %%r21, %0\n"
+" extru %0, 15, 16, %%r21\n"
+" add %0, %%r21, %0\n"
+" subi -1, %0, %0\n"
+"2:\n"
+ : "=r" (sum), "=r" (iph), "=r" (ihl)
+ : "1" (iph), "2" (ihl)
+ : "r19", "r20", "r21", "memory");
+
+ return (__force __sum16)sum;
+}
+
+/*
+ * Fold a partial checksum
+ */
+static inline __sum16 csum_fold(__wsum csum)
+{
+ u32 sum = (__force u32)csum;
+ /* add the swapped two 16-bit halves of sum,
+ a possible carry from adding the two 16-bit halves,
+ will carry from the lower half into the upper half,
+ giving us the correct sum in the upper half. */
+ sum += (sum << 16) + (sum >> 16);
+ return (__force __sum16)(~sum >> 16);
+}
+
+static inline __wsum csum_tcpudp_nofold(__be32 saddr, __be32 daddr,
+ unsigned short len,
+ unsigned short proto,
+ __wsum sum)
+{
+ __asm__(
+ " add %1, %0, %0\n"
+ " addc %2, %0, %0\n"
+ " addc %3, %0, %0\n"
+ " addc %%r0, %0, %0\n"
+ : "=r" (sum)
+ : "r" (daddr), "r"(saddr), "r"(proto+len), "0"(sum));
+ return sum;
+}
+
+/*
+ * computes the checksum of the TCP/UDP pseudo-header
+ * returns a 16-bit checksum, already complemented
+ */
+static inline __sum16 csum_tcpudp_magic(__be32 saddr, __be32 daddr,
+ unsigned short len,
+ unsigned short proto,
+ __wsum sum)
+{
+ return csum_fold(csum_tcpudp_nofold(saddr,daddr,len,proto,sum));
+}
+
+/*
+ * this routine is used for miscellaneous IP-like checksums, mainly
+ * in icmp.c
+ */
+static inline __sum16 ip_compute_csum(const void *buf, int len)
+{
+ return csum_fold (csum_partial(buf, len, 0));
+}
+
+
+#define _HAVE_ARCH_IPV6_CSUM
+static __inline__ __sum16 csum_ipv6_magic(const struct in6_addr *saddr,
+ const struct in6_addr *daddr,
+ __u32 len, unsigned short proto,
+ __wsum sum)
+{
+ __asm__ __volatile__ (
+
+#if BITS_PER_LONG > 32
+
+ /*
+ ** We can execute two loads and two adds per cycle on PA 8000.
+ ** But add insn's get serialized waiting for the carry bit.
+ ** Try to keep 4 registers with "live" values ahead of the ALU.
+ */
+
+" ldd,ma 8(%1), %%r19\n" /* get 1st saddr word */
+" ldd,ma 8(%2), %%r20\n" /* get 1st daddr word */
+" add %8, %3, %3\n"/* add 16-bit proto + len */
+" add %%r19, %0, %0\n"
+" ldd,ma 8(%1), %%r21\n" /* 2cd saddr */
+" ldd,ma 8(%2), %%r22\n" /* 2cd daddr */
+" add,dc %%r20, %0, %0\n"
+" add,dc %%r21, %0, %0\n"
+" add,dc %%r22, %0, %0\n"
+" add,dc %3, %0, %0\n" /* fold in proto+len | carry bit */
+" extrd,u %0, 31, 32, %%r19\n" /* copy upper half down */
+" depdi 0, 31, 32, %0\n" /* clear upper half */
+" add %%r19, %0, %0\n" /* fold into 32-bits */
+" addc 0, %0, %0\n" /* add carry */
+
+#else
+
+ /*
+ ** For PA 1.x, the insn order doesn't matter as much.
+ ** Insn stream is serialized on the carry bit here too.
+ ** result from the previous operation (eg r0 + x)
+ */
+
+" ldw,ma 4(%1), %%r19\n" /* get 1st saddr word */
+" ldw,ma 4(%2), %%r20\n" /* get 1st daddr word */
+" add %8, %3, %3\n" /* add 16-bit proto + len */
+" add %%r19, %0, %0\n"
+" ldw,ma 4(%1), %%r21\n" /* 2cd saddr */
+" addc %%r20, %0, %0\n"
+" ldw,ma 4(%2), %%r22\n" /* 2cd daddr */
+" addc %%r21, %0, %0\n"
+" ldw,ma 4(%1), %%r19\n" /* 3rd saddr */
+" addc %%r22, %0, %0\n"
+" ldw,ma 4(%2), %%r20\n" /* 3rd daddr */
+" addc %%r19, %0, %0\n"
+" ldw,ma 4(%1), %%r21\n" /* 4th saddr */
+" addc %%r20, %0, %0\n"
+" ldw,ma 4(%2), %%r22\n" /* 4th daddr */
+" addc %%r21, %0, %0\n"
+" addc %%r22, %0, %0\n"
+" addc %3, %0, %0\n" /* fold in proto+len, catch carry */
+
+#endif
+ : "=r" (sum), "=r" (saddr), "=r" (daddr), "=r" (len)
+ : "0" (sum), "1" (saddr), "2" (daddr), "3" (len), "r" (proto)
+ : "r19", "r20", "r21", "r22", "memory");
+ return csum_fold(sum);
+}
+
+/*
+ * Copy and checksum to user
+ */
+#define HAVE_CSUM_COPY_USER
+static __inline__ __wsum csum_and_copy_to_user(const void *src,
+ void __user *dst,
+ int len, __wsum sum,
+ int *err_ptr)
+{
+ /* code stolen from include/asm-mips64 */
+ sum = csum_partial(src, len, sum);
+
+ if (copy_to_user(dst, src, len)) {
+ *err_ptr = -EFAULT;
+ return (__force __wsum)-1;
+ }
+
+ return sum;
+}
+
+#endif
+