1 /* 2 * Copyright (C) 2000, 2001, 2002 Jeff Dike (jdike@karaya.com) 3 * Licensed under the GPL 4 */ 5 6 #include <stdlib.h> 7 #include <unistd.h> 8 #include <errno.h> 9 #include <signal.h> 10 #include <string.h> 11 #include <sys/poll.h> 12 #include <sys/types.h> 13 #include <sys/time.h> 14 #include "kern_util.h" 15 #include "user.h" 16 #include "process.h" 17 #include "sigio.h" 18 #include "irq_user.h" 19 #include "os.h" 20 #include "um_malloc.h" 21 22 /* 23 * Locked by irq_lock in arch/um/kernel/irq.c. Changed by os_create_pollfd 24 * and os_free_irq_by_cb, which are called under irq_lock. 25 */ 26 static struct pollfd *pollfds = NULL; 27 static int pollfds_num = 0; 28 static int pollfds_size = 0; 29 30 int os_waiting_for_events(struct irq_fd *active_fds) 31 { 32 struct irq_fd *irq_fd; 33 int i, n, err; 34 35 n = poll(pollfds, pollfds_num, 0); 36 if (n < 0) { 37 err = -errno; 38 if (errno != EINTR) 39 printk("sigio_handler: os_waiting_for_events:" 40 " poll returned %d, errno = %d\n", n, errno); 41 return err; 42 } 43 44 if (n == 0) 45 return 0; 46 47 irq_fd = active_fds; 48 49 for (i = 0; i < pollfds_num; i++) { 50 if (pollfds[i].revents != 0) { 51 irq_fd->current_events = pollfds[i].revents; 52 pollfds[i].fd = -1; 53 } 54 irq_fd = irq_fd->next; 55 } 56 return n; 57 } 58 59 int os_create_pollfd(int fd, int events, void *tmp_pfd, int size_tmpfds) 60 { 61 if (pollfds_num == pollfds_size) { 62 if (size_tmpfds <= pollfds_size * sizeof(pollfds[0])) { 63 /* return min size needed for new pollfds area */ 64 return (pollfds_size + 1) * sizeof(pollfds[0]); 65 } 66 67 if (pollfds != NULL) { 68 memcpy(tmp_pfd, pollfds, 69 sizeof(pollfds[0]) * pollfds_size); 70 /* remove old pollfds */ 71 kfree(pollfds); 72 } 73 pollfds = tmp_pfd; 74 pollfds_size++; 75 } else 76 kfree(tmp_pfd); /* remove not used tmp_pfd */ 77 78 pollfds[pollfds_num] = ((struct pollfd) { .fd = fd, 79 .events = events, 80 .revents = 0 }); 81 pollfds_num++; 82 83 return 0; 84 } 85 86 void os_free_irq_by_cb(int (*test)(struct irq_fd *, void *), void *arg, 87 struct irq_fd *active_fds, struct irq_fd ***last_irq_ptr2) 88 { 89 struct irq_fd **prev; 90 int i = 0; 91 92 prev = &active_fds; 93 while (*prev != NULL) { 94 if ((*test)(*prev, arg)) { 95 struct irq_fd *old_fd = *prev; 96 if ((pollfds[i].fd != -1) && 97 (pollfds[i].fd != (*prev)->fd)) { 98 printk("os_free_irq_by_cb - mismatch between " 99 "active_fds and pollfds, fd %d vs %d\n", 100 (*prev)->fd, pollfds[i].fd); 101 goto out; 102 } 103 104 pollfds_num--; 105 106 /* This moves the *whole* array after pollfds[i] 107 * (though it doesn't spot as such)! 108 */ 109 memmove(&pollfds[i], &pollfds[i + 1], 110 (pollfds_num - i) * sizeof(pollfds[0])); 111 if(*last_irq_ptr2 == &old_fd->next) 112 *last_irq_ptr2 = prev; 113 114 *prev = (*prev)->next; 115 if(old_fd->type == IRQ_WRITE) 116 ignore_sigio_fd(old_fd->fd); 117 kfree(old_fd); 118 continue; 119 } 120 prev = &(*prev)->next; 121 i++; 122 } 123 out: 124 return; 125 } 126 127 int os_get_pollfd(int i) 128 { 129 return pollfds[i].fd; 130 } 131 132 void os_set_pollfd(int i, int fd) 133 { 134 pollfds[i].fd = fd; 135 } 136 137 void os_set_ioignore(void) 138 { 139 signal(SIGIO, SIG_IGN); 140 } 141 142 void init_irq_signals(int on_sigstack) 143 { 144 int flags; 145 146 flags = on_sigstack ? SA_ONSTACK : 0; 147 148 set_handler(SIGVTALRM, (__sighandler_t) alarm_handler, 149 flags | SA_RESTART, SIGUSR1, SIGIO, SIGWINCH, SIGALRM, -1); 150 set_handler(SIGALRM, (__sighandler_t) alarm_handler, 151 flags | SA_RESTART, SIGUSR1, SIGIO, SIGWINCH, SIGALRM, -1); 152 set_handler(SIGIO, (__sighandler_t) sig_handler, flags | SA_RESTART, 153 SIGUSR1, SIGIO, SIGWINCH, SIGALRM, SIGVTALRM, -1); 154 signal(SIGWINCH, SIG_IGN); 155 } 156