1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * Copyright (C) 2007-2010 Lawrence Livermore National Security, LLC. 4 * Copyright (C) 2007 The Regents of the University of California. 5 * Produced at Lawrence Livermore National Laboratory (cf, DISCLAIMER). 6 * Written by Brian Behlendorf <behlendorf1@llnl.gov>. 7 * UCRL-CODE-235197 8 * 9 * This file is part of the SPL, Solaris Porting Layer. 10 * 11 * The SPL is free software; you can redistribute it and/or modify it 12 * under the terms of the GNU General Public License as published by the 13 * Free Software Foundation; either version 2 of the License, or (at your 14 * option) any later version. 15 * 16 * The SPL is distributed in the hope that it will be useful, but WITHOUT 17 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 18 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 19 * for more details. 20 * 21 * You should have received a copy of the GNU General Public License along 22 * with the SPL. If not, see <http://www.gnu.org/licenses/>. 23 * 24 * Solaris Porting Layer (SPL) Thread Implementation. 25 */ 26 27 #include <sys/thread.h> 28 #include <sys/kmem.h> 29 #include <sys/tsd.h> 30 #include <sys/string.h> 31 32 /* 33 * Thread interfaces 34 */ 35 typedef struct thread_priv_s { 36 unsigned long tp_magic; /* Magic */ 37 int tp_name_size; /* Name size */ 38 char *tp_name; /* Name (without _thread suffix) */ 39 void (*tp_func)(void *); /* Registered function */ 40 void *tp_args; /* Args to be passed to function */ 41 size_t tp_len; /* Len to be passed to function */ 42 int tp_state; /* State to start thread at */ 43 pri_t tp_pri; /* Priority to start threat at */ 44 } thread_priv_t; 45 46 static int 47 thread_generic_wrapper(void *arg) 48 { 49 thread_priv_t *tp = (thread_priv_t *)arg; 50 void (*func)(void *); 51 void *args; 52 53 ASSERT(tp->tp_magic == TP_MAGIC); 54 func = tp->tp_func; 55 args = tp->tp_args; 56 set_current_state(tp->tp_state); 57 set_user_nice((kthread_t *)current, PRIO_TO_NICE(tp->tp_pri)); 58 kmem_free(tp->tp_name, tp->tp_name_size); 59 kmem_free(tp, sizeof (thread_priv_t)); 60 61 if (func) 62 func(args); 63 64 return (0); 65 } 66 67 /* 68 * thread_create() may block forever if it cannot create a thread or 69 * allocate memory. This is preferable to returning a NULL which Solaris 70 * style callers likely never check for... since it can't fail. 71 */ 72 kthread_t * 73 __thread_create(caddr_t stk, size_t stksize, thread_func_t func, 74 const char *name, void *args, size_t len, proc_t *pp, int state, pri_t pri) 75 { 76 thread_priv_t *tp; 77 struct task_struct *tsk; 78 char *p; 79 80 /* Option pp is simply ignored */ 81 /* Variable stack size unsupported */ 82 ASSERT(stk == NULL); 83 84 tp = kmem_alloc(sizeof (thread_priv_t), KM_PUSHPAGE); 85 if (tp == NULL) 86 return (NULL); 87 88 tp->tp_magic = TP_MAGIC; 89 tp->tp_name_size = strlen(name) + 1; 90 91 tp->tp_name = kmem_alloc(tp->tp_name_size, KM_PUSHPAGE); 92 if (tp->tp_name == NULL) { 93 kmem_free(tp, sizeof (thread_priv_t)); 94 return (NULL); 95 } 96 97 strlcpy(tp->tp_name, name, tp->tp_name_size); 98 99 /* 100 * Strip trailing "_thread" from passed name which will be the func 101 * name since the exposed API has no parameter for passing a name. 102 */ 103 p = strstr(tp->tp_name, "_thread"); 104 if (p) 105 p[0] = '\0'; 106 107 tp->tp_func = func; 108 tp->tp_args = args; 109 tp->tp_len = len; 110 tp->tp_state = state; 111 tp->tp_pri = pri; 112 113 tsk = spl_kthread_create(thread_generic_wrapper, (void *)tp, 114 "%s", tp->tp_name); 115 if (IS_ERR(tsk)) 116 return (NULL); 117 118 wake_up_process(tsk); 119 return ((kthread_t *)tsk); 120 } 121 EXPORT_SYMBOL(__thread_create); 122 123 /* 124 * spl_kthread_create - Wrapper providing pre-3.13 semantics for 125 * kthread_create() in which it is not killable and less likely 126 * to return -ENOMEM. 127 */ 128 struct task_struct * 129 spl_kthread_create(int (*func)(void *), void *data, const char namefmt[], ...) 130 { 131 struct task_struct *tsk; 132 va_list args; 133 char name[TASK_COMM_LEN]; 134 135 va_start(args, namefmt); 136 vsnprintf(name, sizeof (name), namefmt, args); 137 va_end(args); 138 do { 139 tsk = kthread_create(func, data, "%s", name); 140 if (IS_ERR(tsk)) { 141 if (signal_pending(current)) { 142 clear_thread_flag(TIF_SIGPENDING); 143 continue; 144 } 145 if (PTR_ERR(tsk) == -ENOMEM) 146 continue; 147 return (NULL); 148 } else { 149 return (tsk); 150 } 151 } while (1); 152 } 153 EXPORT_SYMBOL(spl_kthread_create); 154 155 /* 156 * Extract the next pending signal from p_sig into p_cursig; stop the process 157 * if a stop has been requested or if a traced signal is pending. 158 */ 159 int 160 issig(void) 161 { 162 163 if (!signal_pending(current)) 164 return (0); 165 166 spl_kernel_siginfo_t __info; 167 sigset_t set; 168 siginitsetinv(&set, 1ULL << (SIGSTOP - 1) | 1ULL << (SIGTSTP - 1)); 169 sigorsets(&set, ¤t->blocked, &set); 170 171 spin_lock_irq(¤t->sighand->siglock); 172 #if defined(HAVE_DEQUEUE_SIGNAL_4ARG) 173 enum pid_type __type; 174 if (dequeue_signal(current, &set, &__info, &__type) != 0) { 175 #elif defined(HAVE_DEQUEUE_SIGNAL_3ARG_TYPE) 176 enum pid_type __type; 177 if (dequeue_signal(&set, &__info, &__type) != 0) { 178 #else 179 if (dequeue_signal(current, &set, &__info) != 0) { 180 #endif 181 spin_unlock_irq(¤t->sighand->siglock); 182 kernel_signal_stop(); 183 184 /* 185 * Dequeued SIGSTOP/SIGTSTP. 186 * Check if process has other singal pending. 187 */ 188 if (signal_pending(current)) 189 return (1); 190 191 return (0); 192 } 193 194 spin_unlock_irq(¤t->sighand->siglock); 195 196 return (1); 197 } 198 199 EXPORT_SYMBOL(issig); 200