+++ /dev/null
-/*****************************************************************************\
- * Copyright (C) 2007-2010 Lawrence Livermore National Security, LLC.
- * Copyright (C) 2007 The Regents of the University of California.
- * Produced at Lawrence Livermore National Laboratory (cf, DISCLAIMER).
- * Written by Brian Behlendorf <behlendorf1@llnl.gov>.
- * UCRL-CODE-235197
- *
- * This file is part of the SPL, Solaris Porting Layer.
- * For details, see <http://zfsonlinux.org/>.
- *
- * The SPL 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.
- *
- * The SPL is distributed in the hope that it will be useful, but WITHOUT
- * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
- * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
- * for more details.
- *
- * You should have received a copy of the GNU General Public License along
- * with the SPL. If not, see <http://www.gnu.org/licenses/>.
- *****************************************************************************
- * Solaris Porting Layer (SPL) Generic Implementation.
-\*****************************************************************************/
-
-#include <sys/sysmacros.h>
-#include <sys/systeminfo.h>
-#include <sys/vmsystm.h>
-#include <sys/kobj.h>
-#include <sys/kmem.h>
-#include <sys/kmem_cache.h>
-#include <sys/vmem.h>
-#include <sys/mutex.h>
-#include <sys/rwlock.h>
-#include <sys/taskq.h>
-#include <sys/tsd.h>
-#include <sys/zmod.h>
-#include <sys/debug.h>
-#include <sys/proc.h>
-#include <sys/kstat.h>
-#include <sys/file.h>
-#include <linux/ctype.h>
-#include <sys/disp.h>
-#include <sys/random.h>
-#include <linux/kmod.h>
-#include <linux/math64_compat.h>
-#include <linux/proc_compat.h>
-
-char spl_version[32] = "SPL v" SPL_META_VERSION "-" SPL_META_RELEASE;
-EXPORT_SYMBOL(spl_version);
-
-unsigned long spl_hostid = 0;
-EXPORT_SYMBOL(spl_hostid);
-module_param(spl_hostid, ulong, 0644);
-MODULE_PARM_DESC(spl_hostid, "The system hostid.");
-
-proc_t p0;
-EXPORT_SYMBOL(p0);
-
-/*
- * Xorshift Pseudo Random Number Generator based on work by Sebastiano Vigna
- *
- * "Further scramblings of Marsaglia's xorshift generators"
- * http://vigna.di.unimi.it/ftp/papers/xorshiftplus.pdf
- *
- * random_get_pseudo_bytes() is an API function on Illumos whose sole purpose
- * is to provide bytes containing random numbers. It is mapped to /dev/urandom
- * on Illumos, which uses a "FIPS 186-2 algorithm". No user of the SPL's
- * random_get_pseudo_bytes() needs bytes that are of cryptographic quality, so
- * we can implement it using a fast PRNG that we seed using Linux' actual
- * equivalent to random_get_pseudo_bytes(). We do this by providing each CPU
- * with an independent seed so that all calls to random_get_pseudo_bytes() are
- * free of atomic instructions.
- *
- * A consequence of using a fast PRNG is that using random_get_pseudo_bytes()
- * to generate words larger than 128 bits will paradoxically be limited to
- * `2^128 - 1` possibilities. This is because we have a sequence of `2^128 - 1`
- * 128-bit words and selecting the first will implicitly select the second. If
- * a caller finds this behavior undesireable, random_get_bytes() should be used
- * instead.
- *
- * XXX: Linux interrupt handlers that trigger within the critical section
- * formed by `s[1] = xp[1];` and `xp[0] = s[0];` and call this function will
- * see the same numbers. Nothing in the code currently calls this in an
- * interrupt handler, so this is considered to be okay. If that becomes a
- * problem, we could create a set of per-cpu variables for interrupt handlers
- * and use them when in_interrupt() from linux/preempt_mask.h evaluates to
- * true.
- */
-static DEFINE_PER_CPU(uint64_t[2], spl_pseudo_entropy);
-
-/*
- * spl_rand_next()/spl_rand_jump() are copied from the following CC-0 licensed
- * file:
- *
- * http://xorshift.di.unimi.it/xorshift128plus.c
- */
-
-static inline uint64_t
-spl_rand_next(uint64_t *s) {
- uint64_t s1 = s[0];
- const uint64_t s0 = s[1];
- s[0] = s0;
- s1 ^= s1 << 23; // a
- s[1] = s1 ^ s0 ^ (s1 >> 18) ^ (s0 >> 5); // b, c
- return (s[1] + s0);
-}
-
-static inline void
-spl_rand_jump(uint64_t *s) {
- static const uint64_t JUMP[] = { 0x8a5cd789635d2dff, 0x121fd2155c472f96 };
-
- uint64_t s0 = 0;
- uint64_t s1 = 0;
- int i, b;
- for(i = 0; i < sizeof JUMP / sizeof *JUMP; i++)
- for(b = 0; b < 64; b++) {
- if (JUMP[i] & 1ULL << b) {
- s0 ^= s[0];
- s1 ^= s[1];
- }
- (void) spl_rand_next(s);
- }
-
- s[0] = s0;
- s[1] = s1;
-}
-
-int
-random_get_pseudo_bytes(uint8_t *ptr, size_t len)
-{
- uint64_t *xp, s[2];
-
- ASSERT(ptr);
-
- xp = get_cpu_var(spl_pseudo_entropy);
-
- s[0] = xp[0];
- s[1] = xp[1];
-
- while (len) {
- union {
- uint64_t ui64;
- uint8_t byte[sizeof (uint64_t)];
- }entropy;
- int i = MIN(len, sizeof (uint64_t));
-
- len -= i;
- entropy.ui64 = spl_rand_next(s);
-
- while (i--)
- *ptr++ = entropy.byte[i];
- }
-
- xp[0] = s[0];
- xp[1] = s[1];
-
- put_cpu_var(spl_pseudo_entropy);
-
- return (0);
-}
-
-
-EXPORT_SYMBOL(random_get_pseudo_bytes);
-
-#if BITS_PER_LONG == 32
-/*
- * Support 64/64 => 64 division on a 32-bit platform. While the kernel
- * provides a div64_u64() function for this we do not use it because the
- * implementation is flawed. There are cases which return incorrect
- * results as late as linux-2.6.35. Until this is fixed upstream the
- * spl must provide its own implementation.
- *
- * This implementation is a slightly modified version of the algorithm
- * proposed by the book 'Hacker's Delight'. The original source can be
- * found here and is available for use without restriction.
- *
- * http://www.hackersdelight.org/HDcode/newCode/divDouble.c
- */
-
-/*
- * Calculate number of leading of zeros for a 64-bit value.
- */
-static int
-nlz64(uint64_t x) {
- register int n = 0;
-
- if (x == 0)
- return 64;
-
- if (x <= 0x00000000FFFFFFFFULL) {n = n + 32; x = x << 32;}
- if (x <= 0x0000FFFFFFFFFFFFULL) {n = n + 16; x = x << 16;}
- if (x <= 0x00FFFFFFFFFFFFFFULL) {n = n + 8; x = x << 8;}
- if (x <= 0x0FFFFFFFFFFFFFFFULL) {n = n + 4; x = x << 4;}
- if (x <= 0x3FFFFFFFFFFFFFFFULL) {n = n + 2; x = x << 2;}
- if (x <= 0x7FFFFFFFFFFFFFFFULL) {n = n + 1;}
-
- return n;
-}
-
-/*
- * Newer kernels have a div_u64() function but we define our own
- * to simplify portibility between kernel versions.
- */
-static inline uint64_t
-__div_u64(uint64_t u, uint32_t v)
-{
- (void) do_div(u, v);
- return u;
-}
-
-/*
- * Implementation of 64-bit unsigned division for 32-bit machines.
- *
- * First the procedure takes care of the case in which the divisor is a
- * 32-bit quantity. There are two subcases: (1) If the left half of the
- * dividend is less than the divisor, one execution of do_div() is all that
- * is required (overflow is not possible). (2) Otherwise it does two
- * divisions, using the grade school method.
- */
-uint64_t
-__udivdi3(uint64_t u, uint64_t v)
-{
- uint64_t u0, u1, v1, q0, q1, k;
- int n;
-
- if (v >> 32 == 0) { // If v < 2**32:
- if (u >> 32 < v) { // If u/v cannot overflow,
- return __div_u64(u, v); // just do one division.
- } else { // If u/v would overflow:
- u1 = u >> 32; // Break u into two halves.
- u0 = u & 0xFFFFFFFF;
- q1 = __div_u64(u1, v); // First quotient digit.
- k = u1 - q1 * v; // First remainder, < v.
- u0 += (k << 32);
- q0 = __div_u64(u0, v); // Seconds quotient digit.
- return (q1 << 32) + q0;
- }
- } else { // If v >= 2**32:
- n = nlz64(v); // 0 <= n <= 31.
- v1 = (v << n) >> 32; // Normalize divisor, MSB is 1.
- u1 = u >> 1; // To ensure no overflow.
- q1 = __div_u64(u1, v1); // Get quotient from
- q0 = (q1 << n) >> 31; // Undo normalization and
- // division of u by 2.
- if (q0 != 0) // Make q0 correct or
- q0 = q0 - 1; // too small by 1.
- if ((u - q0 * v) >= v)
- q0 = q0 + 1; // Now q0 is correct.
-
- return q0;
- }
-}
-EXPORT_SYMBOL(__udivdi3);
-
-/*
- * Implementation of 64-bit signed division for 32-bit machines.
- */
-int64_t
-__divdi3(int64_t u, int64_t v)
-{
- int64_t q, t;
- q = __udivdi3(abs64(u), abs64(v));
- t = (u ^ v) >> 63; // If u, v have different
- return (q ^ t) - t; // signs, negate q.
-}
-EXPORT_SYMBOL(__divdi3);
-
-/*
- * Implementation of 64-bit unsigned modulo for 32-bit machines.
- */
-uint64_t
-__umoddi3(uint64_t dividend, uint64_t divisor)
-{
- return (dividend - (divisor * __udivdi3(dividend, divisor)));
-}
-EXPORT_SYMBOL(__umoddi3);
-
-/*
- * Implementation of 64-bit unsigned division/modulo for 32-bit machines.
- */
-uint64_t
-__udivmoddi4(uint64_t n, uint64_t d, uint64_t *r)
-{
- uint64_t q = __udivdi3(n, d);
- if (r)
- *r = n - d * q;
- return (q);
-}
-EXPORT_SYMBOL(__udivmoddi4);
-
-/*
- * Implementation of 64-bit signed division/modulo for 32-bit machines.
- */
-int64_t
-__divmoddi4(int64_t n, int64_t d, int64_t *r)
-{
- int64_t q, rr;
- boolean_t nn = B_FALSE;
- boolean_t nd = B_FALSE;
- if (n < 0) {
- nn = B_TRUE;
- n = -n;
- }
- if (d < 0) {
- nd = B_TRUE;
- d = -d;
- }
-
- q = __udivmoddi4(n, d, (uint64_t *)&rr);
-
- if (nn != nd)
- q = -q;
- if (nn)
- rr = -rr;
- if (r)
- *r = rr;
- return (q);
-}
-EXPORT_SYMBOL(__divmoddi4);
-
-#if defined(__arm) || defined(__arm__)
-/*
- * Implementation of 64-bit (un)signed division for 32-bit arm machines.
- *
- * Run-time ABI for the ARM Architecture (page 20). A pair of (unsigned)
- * long longs is returned in {{r0, r1}, {r2,r3}}, the quotient in {r0, r1},
- * and the remainder in {r2, r3}. The return type is specifically left
- * set to 'void' to ensure the compiler does not overwrite these registers
- * during the return. All results are in registers as per ABI
- */
-void
-__aeabi_uldivmod(uint64_t u, uint64_t v)
-{
- uint64_t res;
- uint64_t mod;
-
- res = __udivdi3(u, v);
- mod = __umoddi3(u, v);
- {
- register uint32_t r0 asm("r0") = (res & 0xFFFFFFFF);
- register uint32_t r1 asm("r1") = (res >> 32);
- register uint32_t r2 asm("r2") = (mod & 0xFFFFFFFF);
- register uint32_t r3 asm("r3") = (mod >> 32);
-
- asm volatile(""
- : "+r"(r0), "+r"(r1), "+r"(r2),"+r"(r3) /* output */
- : "r"(r0), "r"(r1), "r"(r2), "r"(r3)); /* input */
-
- return; /* r0; */
- }
-}
-EXPORT_SYMBOL(__aeabi_uldivmod);
-
-void
-__aeabi_ldivmod(int64_t u, int64_t v)
-{
- int64_t res;
- uint64_t mod;
-
- res = __divdi3(u, v);
- mod = __umoddi3(u, v);
- {
- register uint32_t r0 asm("r0") = (res & 0xFFFFFFFF);
- register uint32_t r1 asm("r1") = (res >> 32);
- register uint32_t r2 asm("r2") = (mod & 0xFFFFFFFF);
- register uint32_t r3 asm("r3") = (mod >> 32);
-
- asm volatile(""
- : "+r"(r0), "+r"(r1), "+r"(r2),"+r"(r3) /* output */
- : "r"(r0), "r"(r1), "r"(r2), "r"(r3)); /* input */
-
- return; /* r0; */
- }
-}
-EXPORT_SYMBOL(__aeabi_ldivmod);
-#endif /* __arm || __arm__ */
-#endif /* BITS_PER_LONG */
-
-/* NOTE: The strtoxx behavior is solely based on my reading of the Solaris
- * ddi_strtol(9F) man page. I have not verified the behavior of these
- * functions against their Solaris counterparts. It is possible that I
- * may have misinterpreted the man page or the man page is incorrect.
- */
-int ddi_strtoul(const char *, char **, int, unsigned long *);
-int ddi_strtol(const char *, char **, int, long *);
-int ddi_strtoull(const char *, char **, int, unsigned long long *);
-int ddi_strtoll(const char *, char **, int, long long *);
-
-#define define_ddi_strtoux(type, valtype) \
-int ddi_strtou##type(const char *str, char **endptr, \
- int base, valtype *result) \
-{ \
- valtype last_value, value = 0; \
- char *ptr = (char *)str; \
- int flag = 1, digit; \
- \
- if (strlen(ptr) == 0) \
- return EINVAL; \
- \
- /* Auto-detect base based on prefix */ \
- if (!base) { \
- if (str[0] == '0') { \
- if (tolower(str[1])=='x' && isxdigit(str[2])) { \
- base = 16; /* hex */ \
- ptr += 2; \
- } else if (str[1] >= '0' && str[1] < 8) { \
- base = 8; /* octal */ \
- ptr += 1; \
- } else { \
- return EINVAL; \
- } \
- } else { \
- base = 10; /* decimal */ \
- } \
- } \
- \
- while (1) { \
- if (isdigit(*ptr)) \
- digit = *ptr - '0'; \
- else if (isalpha(*ptr)) \
- digit = tolower(*ptr) - 'a' + 10; \
- else \
- break; \
- \
- if (digit >= base) \
- break; \
- \
- last_value = value; \
- value = value * base + digit; \
- if (last_value > value) /* Overflow */ \
- return ERANGE; \
- \
- flag = 1; \
- ptr++; \
- } \
- \
- if (flag) \
- *result = value; \
- \
- if (endptr) \
- *endptr = (char *)(flag ? ptr : str); \
- \
- return 0; \
-} \
-
-#define define_ddi_strtox(type, valtype) \
-int ddi_strto##type(const char *str, char **endptr, \
- int base, valtype *result) \
-{ \
- int rc; \
- \
- if (*str == '-') { \
- rc = ddi_strtou##type(str + 1, endptr, base, result); \
- if (!rc) { \
- if (*endptr == str + 1) \
- *endptr = (char *)str; \
- else \
- *result = -*result; \
- } \
- } else { \
- rc = ddi_strtou##type(str, endptr, base, result); \
- } \
- \
- return rc; \
-}
-
-define_ddi_strtoux(l, unsigned long)
-define_ddi_strtox(l, long)
-define_ddi_strtoux(ll, unsigned long long)
-define_ddi_strtox(ll, long long)
-
-EXPORT_SYMBOL(ddi_strtoul);
-EXPORT_SYMBOL(ddi_strtol);
-EXPORT_SYMBOL(ddi_strtoll);
-EXPORT_SYMBOL(ddi_strtoull);
-
-int
-ddi_copyin(const void *from, void *to, size_t len, int flags)
-{
- /* Fake ioctl() issued by kernel, 'from' is a kernel address */
- if (flags & FKIOCTL) {
- memcpy(to, from, len);
- return 0;
- }
-
- return copyin(from, to, len);
-}
-EXPORT_SYMBOL(ddi_copyin);
-
-int
-ddi_copyout(const void *from, void *to, size_t len, int flags)
-{
- /* Fake ioctl() issued by kernel, 'from' is a kernel address */
- if (flags & FKIOCTL) {
- memcpy(to, from, len);
- return 0;
- }
-
- return copyout(from, to, len);
-}
-EXPORT_SYMBOL(ddi_copyout);
-
-/*
- * Read the unique system identifier from the /etc/hostid file.
- *
- * The behavior of /usr/bin/hostid on Linux systems with the
- * regular eglibc and coreutils is:
- *
- * 1. Generate the value if the /etc/hostid file does not exist
- * or if the /etc/hostid file is less than four bytes in size.
- *
- * 2. If the /etc/hostid file is at least 4 bytes, then return
- * the first four bytes [0..3] in native endian order.
- *
- * 3. Always ignore bytes [4..] if they exist in the file.
- *
- * Only the first four bytes are significant, even on systems that
- * have a 64-bit word size.
- *
- * See:
- *
- * eglibc: sysdeps/unix/sysv/linux/gethostid.c
- * coreutils: src/hostid.c
- *
- * Notes:
- *
- * The /etc/hostid file on Solaris is a text file that often reads:
- *
- * # DO NOT EDIT
- * "0123456789"
- *
- * Directly copying this file to Linux results in a constant
- * hostid of 4f442023 because the default comment constitutes
- * the first four bytes of the file.
- *
- */
-
-char *spl_hostid_path = HW_HOSTID_PATH;
-module_param(spl_hostid_path, charp, 0444);
-MODULE_PARM_DESC(spl_hostid_path, "The system hostid file (/etc/hostid)");
-
-static int
-hostid_read(uint32_t *hostid)
-{
- uint64_t size;
- struct _buf *file;
- uint32_t value = 0;
- int error;
-
- file = kobj_open_file(spl_hostid_path);
- if (file == (struct _buf *)-1)
- return (ENOENT);
-
- error = kobj_get_filesize(file, &size);
- if (error) {
- kobj_close_file(file);
- return (error);
- }
-
- if (size < sizeof(HW_HOSTID_MASK)) {
- kobj_close_file(file);
- return (EINVAL);
- }
-
- /*
- * Read directly into the variable like eglibc does.
- * Short reads are okay; native behavior is preserved.
- */
- error = kobj_read_file(file, (char *)&value, sizeof(value), 0);
- if (error < 0) {
- kobj_close_file(file);
- return (EIO);
- }
-
- /* Mask down to 32 bits like coreutils does. */
- *hostid = (value & HW_HOSTID_MASK);
- kobj_close_file(file);
-
- return 0;
-}
-
-/*
- * Return the system hostid. Preferentially use the spl_hostid module option
- * when set, otherwise use the value in the /etc/hostid file.
- */
-uint32_t
-zone_get_hostid(void *zone)
-{
- uint32_t hostid;
-
- ASSERT3P(zone, ==, NULL);
-
- if (spl_hostid != 0)
- return ((uint32_t)(spl_hostid & HW_HOSTID_MASK));
-
- if (hostid_read(&hostid) == 0)
- return (hostid);
-
- return (0);
-}
-EXPORT_SYMBOL(zone_get_hostid);
-
-static int
-spl_kvmem_init(void)
-{
- int rc = 0;
-
- rc = spl_kmem_init();
- if (rc)
- return (rc);
-
- rc = spl_vmem_init();
- if (rc) {
- spl_kmem_fini();
- return (rc);
- }
-
- return (rc);
-}
-
-/*
- * We initialize the random number generator with 128 bits of entropy from the
- * system random number generator. In the improbable case that we have a zero
- * seed, we fallback to the system jiffies, unless it is also zero, in which
- * situation we use a preprogrammed seed. We step forward by 2^64 iterations to
- * initialize each of the per-cpu seeds so that the sequences generated on each
- * CPU are guaranteed to never overlap in practice.
- */
-static void __init
-spl_random_init(void)
-{
- uint64_t s[2];
- int i;
-
- get_random_bytes(s, sizeof (s));
-
- if (s[0] == 0 && s[1] == 0) {
- if (jiffies != 0) {
- s[0] = jiffies;
- s[1] = ~0 - jiffies;
- } else {
- (void) memcpy(s, "improbable seed", sizeof (s));
- }
- printk("SPL: get_random_bytes() returned 0 "
- "when generating random seed. Setting initial seed to "
- "0x%016llx%016llx.", cpu_to_be64(s[0]), cpu_to_be64(s[1]));
- }
-
- for_each_possible_cpu(i) {
- uint64_t *wordp = per_cpu(spl_pseudo_entropy, i);
-
- spl_rand_jump(s);
-
- wordp[0] = s[0];
- wordp[1] = s[1];
- }
-}
-
-static void
-spl_kvmem_fini(void)
-{
- spl_vmem_fini();
- spl_kmem_fini();
-}
-
-static int __init
-spl_init(void)
-{
- int rc = 0;
-
- bzero(&p0, sizeof (proc_t));
- spl_random_init();
-
- if ((rc = spl_kvmem_init()))
- goto out1;
-
- if ((rc = spl_mutex_init()))
- goto out2;
-
- if ((rc = spl_rw_init()))
- goto out3;
-
- if ((rc = spl_tsd_init()))
- goto out4;
-
- if ((rc = spl_taskq_init()))
- goto out5;
-
- if ((rc = spl_kmem_cache_init()))
- goto out6;
-
- if ((rc = spl_vn_init()))
- goto out7;
-
- if ((rc = spl_proc_init()))
- goto out8;
-
- if ((rc = spl_kstat_init()))
- goto out9;
-
- if ((rc = spl_zlib_init()))
- goto out10;
-
- printk(KERN_NOTICE "SPL: Loaded module v%s-%s%s\n", SPL_META_VERSION,
- SPL_META_RELEASE, SPL_DEBUG_STR);
- return (rc);
-
-out10:
- spl_kstat_fini();
-out9:
- spl_proc_fini();
-out8:
- spl_vn_fini();
-out7:
- spl_kmem_cache_fini();
-out6:
- spl_taskq_fini();
-out5:
- spl_tsd_fini();
-out4:
- spl_rw_fini();
-out3:
- spl_mutex_fini();
-out2:
- spl_kvmem_fini();
-out1:
- printk(KERN_NOTICE "SPL: Failed to Load Solaris Porting Layer "
- "v%s-%s%s, rc = %d\n", SPL_META_VERSION, SPL_META_RELEASE,
- SPL_DEBUG_STR, rc);
-
- return (rc);
-}
-
-static void __exit
-spl_fini(void)
-{
- printk(KERN_NOTICE "SPL: Unloaded module v%s-%s%s\n",
- SPL_META_VERSION, SPL_META_RELEASE, SPL_DEBUG_STR);
- spl_zlib_fini();
- spl_kstat_fini();
- spl_proc_fini();
- spl_vn_fini();
- spl_kmem_cache_fini();
- spl_taskq_fini();
- spl_tsd_fini();
- spl_rw_fini();
- spl_mutex_fini();
- spl_kvmem_fini();
-}
-
-module_init(spl_init);
-module_exit(spl_fini);
-
-MODULE_DESCRIPTION("Solaris Porting Layer");
-MODULE_AUTHOR(SPL_META_AUTHOR);
-MODULE_LICENSE(SPL_META_LICENSE);
-MODULE_VERSION(SPL_META_VERSION "-" SPL_META_RELEASE);
projects / mirror_ubuntu-bionic-kernel.git / blobdiff