diff options
Diffstat (limited to 'lib')
| -rw-r--r-- | lib/Kconfig | 6 | ||||
| -rw-r--r-- | lib/Makefile | 4 | ||||
| -rw-r--r-- | lib/atomic64.c | 175 | ||||
| -rw-r--r-- | lib/checksum.c | 193 | ||||
| -rw-r--r-- | lib/extable.c | 21 |
5 files changed, 398 insertions, 1 deletions
diff --git a/lib/Kconfig b/lib/Kconfig index 9960be04cbbe..bb1326d3839c 100644 --- a/lib/Kconfig +++ b/lib/Kconfig @@ -194,4 +194,10 @@ config DISABLE_OBSOLETE_CPUMASK_FUNCTIONS config NLATTR bool +# +# Generic 64-bit atomic support is selected if needed +# +config GENERIC_ATOMIC64 + bool + endmenu diff --git a/lib/Makefile b/lib/Makefile index 1f6edefebffe..8e9bcf9d3261 100644 --- a/lib/Makefile +++ b/lib/Makefile @@ -93,6 +93,10 @@ obj-$(CONFIG_NLATTR) += nlattr.o obj-$(CONFIG_DMA_API_DEBUG) += dma-debug.o +obj-$(CONFIG_GENERIC_CSUM) += checksum.o + +obj-$(CONFIG_GENERIC_ATOMIC64) += atomic64.o + hostprogs-y := gen_crc32table clean-files := crc32table.h diff --git a/lib/atomic64.c b/lib/atomic64.c new file mode 100644 index 000000000000..c5e725562416 --- /dev/null +++ b/lib/atomic64.c @@ -0,0 +1,175 @@ +/* + * Generic implementation of 64-bit atomics using spinlocks, + * useful on processors that don't have 64-bit atomic instructions. + * + * Copyright © 2009 Paul Mackerras, IBM Corp. <paulus@au1.ibm.com> + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version + * 2 of the License, or (at your option) any later version. + */ +#include <linux/types.h> +#include <linux/cache.h> +#include <linux/spinlock.h> +#include <linux/init.h> +#include <asm/atomic.h> + +/* + * We use a hashed array of spinlocks to provide exclusive access + * to each atomic64_t variable. Since this is expected to used on + * systems with small numbers of CPUs (<= 4 or so), we use a + * relatively small array of 16 spinlocks to avoid wasting too much + * memory on the spinlock array. + */ +#define NR_LOCKS 16 + +/* + * Ensure each lock is in a separate cacheline. + */ +static union { + spinlock_t lock; + char pad[L1_CACHE_BYTES]; +} atomic64_lock[NR_LOCKS] __cacheline_aligned_in_smp; + +static inline spinlock_t *lock_addr(const atomic64_t *v) +{ + unsigned long addr = (unsigned long) v; + + addr >>= L1_CACHE_SHIFT; + addr ^= (addr >> 8) ^ (addr >> 16); + return &atomic64_lock[addr & (NR_LOCKS - 1)].lock; +} + +long long atomic64_read(const atomic64_t *v) +{ + unsigned long flags; + spinlock_t *lock = lock_addr(v); + long long val; + + spin_lock_irqsave(lock, flags); + val = v->counter; + spin_unlock_irqrestore(lock, flags); + return val; +} + +void atomic64_set(atomic64_t *v, long long i) +{ + unsigned long flags; + spinlock_t *lock = lock_addr(v); + + spin_lock_irqsave(lock, flags); + v->counter = i; + spin_unlock_irqrestore(lock, flags); +} + +void atomic64_add(long long a, atomic64_t *v) +{ + unsigned long flags; + spinlock_t *lock = lock_addr(v); + + spin_lock_irqsave(lock, flags); + v->counter += a; + spin_unlock_irqrestore(lock, flags); +} + +long long atomic64_add_return(long long a, atomic64_t *v) +{ + unsigned long flags; + spinlock_t *lock = lock_addr(v); + long long val; + + spin_lock_irqsave(lock, flags); + val = v->counter += a; + spin_unlock_irqrestore(lock, flags); + return val; +} + +void atomic64_sub(long long a, atomic64_t *v) +{ + unsigned long flags; + spinlock_t *lock = lock_addr(v); + + spin_lock_irqsave(lock, flags); + v->counter -= a; + spin_unlock_irqrestore(lock, flags); +} + +long long atomic64_sub_return(long long a, atomic64_t *v) +{ + unsigned long flags; + spinlock_t *lock = lock_addr(v); + long long val; + + spin_lock_irqsave(lock, flags); + val = v->counter -= a; + spin_unlock_irqrestore(lock, flags); + return val; +} + +long long atomic64_dec_if_positive(atomic64_t *v) +{ + unsigned long flags; + spinlock_t *lock = lock_addr(v); + long long val; + + spin_lock_irqsave(lock, flags); + val = v->counter - 1; + if (val >= 0) + v->counter = val; + spin_unlock_irqrestore(lock, flags); + return val; +} + +long long atomic64_cmpxchg(atomic64_t *v, long long o, long long n) +{ + unsigned long flags; + spinlock_t *lock = lock_addr(v); + long long val; + + spin_lock_irqsave(lock, flags); + val = v->counter; + if (val == o) + v->counter = n; + spin_unlock_irqrestore(lock, flags); + return val; +} + +long long atomic64_xchg(atomic64_t *v, long long new) +{ + unsigned long flags; + spinlock_t *lock = lock_addr(v); + long long val; + + spin_lock_irqsave(lock, flags); + val = v->counter; + v->counter = new; + spin_unlock_irqrestore(lock, flags); + return val; +} + +int atomic64_add_unless(atomic64_t *v, long long a, long long u) +{ + unsigned long flags; + spinlock_t *lock = lock_addr(v); + int ret = 1; + + spin_lock_irqsave(lock, flags); + if (v->counter != u) { + v->counter += a; + ret = 0; + } + spin_unlock_irqrestore(lock, flags); + return ret; +} + +static int init_atomic64_lock(void) +{ + int i; + + for (i = 0; i < NR_LOCKS; ++i) + spin_lock_init(&atomic64_lock[i].lock); + return 0; +} + +pure_initcall(init_atomic64_lock); diff --git a/lib/checksum.c b/lib/checksum.c new file mode 100644 index 000000000000..12e5a1c91cda --- /dev/null +++ b/lib/checksum.c @@ -0,0 +1,193 @@ +/* + * + * INET An implementation of the TCP/IP protocol suite for the LINUX + * operating system. INET is implemented using the BSD Socket + * interface as the means of communication with the user level. + * + * IP/TCP/UDP checksumming routines + * + * Authors: Jorge Cwik, <jorge@laser.satlink.net> + * Arnt Gulbrandsen, <agulbra@nvg.unit.no> + * Tom May, <ftom@netcom.com> + * Andreas Schwab, <schwab@issan.informatik.uni-dortmund.de> + * Lots of code moved from tcp.c and ip.c; see those files + * for more names. + * + * 03/02/96 Jes Sorensen, Andreas Schwab, Roman Hodek: + * Fixed some nasty bugs, causing some horrible crashes. + * A: At some points, the sum (%0) was used as + * length-counter instead of the length counter + * (%1). Thanks to Roman Hodek for pointing this out. + * B: GCC seems to mess up if one uses too many + * data-registers to hold input values and one tries to + * specify d0 and d1 as scratch registers. Letting gcc + * choose these registers itself solves the problem. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version + * 2 of the License, or (at your option) any later version. + */ + +/* Revised by Kenneth Albanowski for m68knommu. Basic problem: unaligned access + kills, so most of the assembly has to go. */ + +#include <linux/module.h> +#include <net/checksum.h> + +#include <asm/byteorder.h> + +static inline unsigned short from32to16(unsigned long x) +{ + /* add up 16-bit and 16-bit for 16+c bit */ + x = (x & 0xffff) + (x >> 16); + /* add up carry.. */ + x = (x & 0xffff) + (x >> 16); + return x; +} + +static unsigned int do_csum(const unsigned char *buff, int len) +{ + int odd, count; + unsigned long result = 0; + + if (len <= 0) + goto out; + odd = 1 & (unsigned long) buff; + if (odd) { + result = *buff; + len--; + buff++; + } + count = len >> 1; /* nr of 16-bit words.. */ + if (count) { + if (2 & (unsigned long) buff) { + result += *(unsigned short *) buff; + count--; + len -= 2; + buff += 2; + } + count >>= 1; /* nr of 32-bit words.. */ + if (count) { + unsigned long carry = 0; + do { + unsigned long w = *(unsigned long *) buff; + count--; + buff += 4; + result += carry; + result += w; + carry = (w > result); + } while (count); + result += carry; + result = (result & 0xffff) + (result >> 16); + } + if (len & 2) { + result += *(unsigned short *) buff; + buff += 2; + } + } + if (len & 1) + result += (*buff << 8); + result = from32to16(result); + if (odd) + result = ((result >> 8) & 0xff) | ((result & 0xff) << 8); +out: + return result; +} + +/* + * This is a version of ip_compute_csum() optimized for IP headers, + * which always checksum on 4 octet boundaries. + */ +__sum16 ip_fast_csum(const void *iph, unsigned int ihl) +{ + return (__force __sum16)~do_csum(iph, ihl*4); +} +EXPORT_SYMBOL(ip_fast_csum); + +/* + * 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 + */ +__wsum csum_partial(const void *buff, int len, __wsum wsum) +{ + unsigned int sum = (__force unsigned int)wsum; + unsigned int result = do_csum(buff, len); + + /* add in old sum, and carry.. */ + result += sum; + if (sum > result) + result += 1; + return (__force __wsum)result; +} +EXPORT_SYMBOL(csum_partial); + +/* + * this routine is used for miscellaneous IP-like checksums, mainly + * in icmp.c + */ +__sum16 ip_compute_csum(const void *buff, int len) +{ + return (__force __sum16)~do_csum(buff, len); +} +EXPORT_SYMBOL(ip_compute_csum); + +/* + * copy from fs while checksumming, otherwise like csum_partial + */ +__wsum +csum_partial_copy_from_user(const void __user *src, void *dst, int len, + __wsum sum, int *csum_err) +{ + int missing; + + missing = __copy_from_user(dst, src, len); + if (missing) { + memset(dst + len - missing, 0, missing); + *csum_err = -EFAULT; + } else + *csum_err = 0; + + return csum_partial(dst, len, sum); +} +EXPORT_SYMBOL(csum_partial_copy_from_user); + +/* + * copy from ds while checksumming, otherwise like csum_partial + */ +__wsum +csum_partial_copy(const void *src, void *dst, int len, __wsum sum) +{ + memcpy(dst, src, len); + return csum_partial(dst, len, sum); +} +EXPORT_SYMBOL(csum_partial_copy); + +#ifndef csum_tcpudp_nofold +__wsum csum_tcpudp_nofold(__be32 saddr, __be32 daddr, + unsigned short len, + unsigned short proto, + __wsum sum) +{ + unsigned long long s = (__force u32)sum; + + s += (__force u32)saddr; + s += (__force u32)daddr; +#ifdef __BIG_ENDIAN + s += proto + len; +#else + s += (proto + len) << 8; +#endif + s += (s >> 32); + return (__force __wsum)s; +} +EXPORT_SYMBOL(csum_tcpudp_nofold); +#endif diff --git a/lib/extable.c b/lib/extable.c index 179c08745595..4cac81ec225e 100644 --- a/lib/extable.c +++ b/lib/extable.c @@ -39,7 +39,26 @@ void sort_extable(struct exception_table_entry *start, sort(start, finish - start, sizeof(struct exception_table_entry), cmp_ex, NULL); } -#endif + +#ifdef CONFIG_MODULES +/* + * If the exception table is sorted, any referring to the module init + * will be at the beginning or the end. + */ +void trim_init_extable(struct module *m) +{ + /*trim the beginning*/ + while (m->num_exentries && within_module_init(m->extable[0].insn, m)) { + m->extable++; + m->num_exentries--; + } + /*trim the end*/ + while (m->num_exentries && + within_module_init(m->extable[m->num_exentries-1].insn, m)) + m->num_exentries--; +} +#endif /* CONFIG_MODULES */ +#endif /* !ARCH_HAS_SORT_EXTABLE */ #ifndef ARCH_HAS_SEARCH_EXTABLE /* |