1 | #include <machine/rtems-bsd-kernel-space.h> |
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2 | |
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3 | /*- |
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4 | * Copyright (c) 1996 John S. Dyson |
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5 | * Copyright (c) 2012 Giovanni Trematerra |
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6 | * All rights reserved. |
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7 | * |
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8 | * Redistribution and use in source and binary forms, with or without |
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9 | * modification, are permitted provided that the following conditions |
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10 | * are met: |
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11 | * 1. Redistributions of source code must retain the above copyright |
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12 | * notice immediately at the beginning of the file, without modification, |
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13 | * this list of conditions, and the following disclaimer. |
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14 | * 2. Redistributions in binary form must reproduce the above copyright |
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15 | * notice, this list of conditions and the following disclaimer in the |
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16 | * documentation and/or other materials provided with the distribution. |
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17 | * 3. Absolutely no warranty of function or purpose is made by the author |
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18 | * John S. Dyson. |
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19 | * 4. Modifications may be freely made to this file if the above conditions |
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20 | * are met. |
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21 | */ |
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22 | |
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23 | /* |
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24 | * This file contains a high-performance replacement for the socket-based |
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25 | * pipes scheme originally used in FreeBSD/4.4Lite. It does not support |
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26 | * all features of sockets, but does do everything that pipes normally |
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27 | * do. |
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28 | */ |
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29 | |
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30 | /* |
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31 | * This code has two modes of operation, a small write mode and a large |
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32 | * write mode. The small write mode acts like conventional pipes with |
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33 | * a kernel buffer. If the buffer is less than PIPE_MINDIRECT, then the |
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34 | * "normal" pipe buffering is done. If the buffer is between PIPE_MINDIRECT |
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35 | * and PIPE_SIZE in size, the sending process pins the underlying pages in |
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36 | * memory, and the receiving process copies directly from these pinned pages |
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37 | * in the sending process. |
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38 | * |
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39 | * If the sending process receives a signal, it is possible that it will |
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40 | * go away, and certainly its address space can change, because control |
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41 | * is returned back to the user-mode side. In that case, the pipe code |
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42 | * arranges to copy the buffer supplied by the user process, to a pageable |
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43 | * kernel buffer, and the receiving process will grab the data from the |
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44 | * pageable kernel buffer. Since signals don't happen all that often, |
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45 | * the copy operation is normally eliminated. |
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46 | * |
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47 | * The constant PIPE_MINDIRECT is chosen to make sure that buffering will |
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48 | * happen for small transfers so that the system will not spend all of |
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49 | * its time context switching. |
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50 | * |
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51 | * In order to limit the resource use of pipes, two sysctls exist: |
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52 | * |
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53 | * kern.ipc.maxpipekva - This is a hard limit on the amount of pageable |
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54 | * address space available to us in pipe_map. This value is normally |
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55 | * autotuned, but may also be loader tuned. |
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56 | * |
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57 | * kern.ipc.pipekva - This read-only sysctl tracks the current amount of |
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58 | * memory in use by pipes. |
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59 | * |
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60 | * Based on how large pipekva is relative to maxpipekva, the following |
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61 | * will happen: |
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62 | * |
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63 | * 0% - 50%: |
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64 | * New pipes are given 16K of memory backing, pipes may dynamically |
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65 | * grow to as large as 64K where needed. |
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66 | * 50% - 75%: |
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67 | * New pipes are given 4K (or PAGE_SIZE) of memory backing, |
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68 | * existing pipes may NOT grow. |
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69 | * 75% - 100%: |
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70 | * New pipes are given 4K (or PAGE_SIZE) of memory backing, |
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71 | * existing pipes will be shrunk down to 4K whenever possible. |
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72 | * |
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73 | * Resizing may be disabled by setting kern.ipc.piperesizeallowed=0. If |
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74 | * that is set, the only resize that will occur is the 0 -> SMALL_PIPE_SIZE |
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75 | * resize which MUST occur for reverse-direction pipes when they are |
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76 | * first used. |
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77 | * |
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78 | * Additional information about the current state of pipes may be obtained |
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79 | * from kern.ipc.pipes, kern.ipc.pipefragretry, kern.ipc.pipeallocfail, |
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80 | * and kern.ipc.piperesizefail. |
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81 | * |
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82 | * Locking rules: There are two locks present here: A mutex, used via |
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83 | * PIPE_LOCK, and a flag, used via pipelock(). All locking is done via |
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84 | * the flag, as mutexes can not persist over uiomove. The mutex |
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85 | * exists only to guard access to the flag, and is not in itself a |
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86 | * locking mechanism. Also note that there is only a single mutex for |
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87 | * both directions of a pipe. |
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88 | * |
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89 | * As pipelock() may have to sleep before it can acquire the flag, it |
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90 | * is important to reread all data after a call to pipelock(); everything |
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91 | * in the structure may have changed. |
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92 | */ |
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93 | |
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94 | #include <rtems/bsd/local/opt_compat.h> |
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95 | |
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96 | #include <sys/cdefs.h> |
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97 | __FBSDID("$FreeBSD$"); |
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98 | |
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99 | #include <sys/param.h> |
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100 | #include <sys/systm.h> |
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101 | #include <sys/conf.h> |
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102 | #include <sys/fcntl.h> |
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103 | #include <sys/file.h> |
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104 | #include <sys/filedesc.h> |
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105 | #include <sys/filio.h> |
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106 | #include <sys/kernel.h> |
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107 | #include <sys/lock.h> |
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108 | #include <sys/mutex.h> |
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109 | #include <sys/ttycom.h> |
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110 | #include <sys/stat.h> |
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111 | #include <sys/malloc.h> |
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112 | #include <sys/poll.h> |
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113 | #include <sys/selinfo.h> |
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114 | #include <sys/signalvar.h> |
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115 | #include <sys/syscallsubr.h> |
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116 | #include <sys/sysctl.h> |
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117 | #include <sys/sysproto.h> |
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118 | #include <sys/pipe.h> |
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119 | #include <sys/proc.h> |
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120 | #include <sys/vnode.h> |
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121 | #include <sys/uio.h> |
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122 | #include <sys/user.h> |
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123 | #include <sys/event.h> |
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124 | |
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125 | #include <security/mac/mac_framework.h> |
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126 | |
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127 | #include <vm/vm.h> |
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128 | #include <vm/vm_param.h> |
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129 | #include <vm/vm_object.h> |
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130 | #include <vm/vm_kern.h> |
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131 | #include <vm/vm_extern.h> |
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132 | #include <vm/pmap.h> |
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133 | #include <vm/vm_map.h> |
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134 | #include <vm/vm_page.h> |
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135 | #include <vm/uma.h> |
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136 | |
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137 | /* |
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138 | * Use this define if you want to disable *fancy* VM things. Expect an |
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139 | * approx 30% decrease in transfer rate. This could be useful for |
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140 | * NetBSD or OpenBSD. |
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141 | */ |
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142 | /* #define PIPE_NODIRECT */ |
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143 | |
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144 | #define PIPE_PEER(pipe) \ |
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145 | (((pipe)->pipe_state & PIPE_NAMED) ? (pipe) : ((pipe)->pipe_peer)) |
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146 | |
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147 | /* |
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148 | * interfaces to the outside world |
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149 | */ |
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150 | #ifndef __rtems__ |
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151 | static fo_rdwr_t pipe_read; |
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152 | static fo_rdwr_t pipe_write; |
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153 | static fo_truncate_t pipe_truncate; |
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154 | static fo_ioctl_t pipe_ioctl; |
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155 | static fo_poll_t pipe_poll; |
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156 | static fo_kqfilter_t pipe_kqfilter; |
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157 | static fo_stat_t pipe_stat; |
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158 | static fo_close_t pipe_close; |
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159 | static fo_chmod_t pipe_chmod; |
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160 | static fo_chown_t pipe_chown; |
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161 | static fo_fill_kinfo_t pipe_fill_kinfo; |
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162 | |
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163 | struct fileops pipeops = { |
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164 | .fo_read = pipe_read, |
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165 | .fo_write = pipe_write, |
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166 | .fo_truncate = pipe_truncate, |
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167 | .fo_ioctl = pipe_ioctl, |
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168 | .fo_poll = pipe_poll, |
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169 | .fo_kqfilter = pipe_kqfilter, |
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170 | .fo_stat = pipe_stat, |
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171 | .fo_close = pipe_close, |
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172 | .fo_chmod = pipe_chmod, |
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173 | .fo_chown = pipe_chown, |
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174 | .fo_sendfile = invfo_sendfile, |
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175 | .fo_fill_kinfo = pipe_fill_kinfo, |
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176 | .fo_flags = DFLAG_PASSABLE |
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177 | }; |
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178 | #else /* __rtems__ */ |
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179 | #define PIPE_NODIRECT |
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180 | #define PRIBIO (0) |
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181 | |
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182 | static int rtems_bsd_pipe_open(rtems_libio_t *iop, const char *path, int oflag, mode_t mode); |
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183 | static int rtems_bsd_pipe_close(rtems_libio_t *iop); |
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184 | static ssize_t rtems_bsd_pipe_read(rtems_libio_t *iop, void *buffer, size_t count); |
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185 | static ssize_t rtems_bsd_pipe_write(rtems_libio_t *iop, const void *buffer, size_t count); |
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186 | static int rtems_bsd_pipe_ioctl(rtems_libio_t *iop, ioctl_command_t request, void *buffer); |
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187 | static int rtems_bsd_pipe_stat(const rtems_filesystem_location_info_t *loc, struct stat *buf); |
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188 | static int rtems_bsd_pipe_fcntl(rtems_libio_t *iop, int cmd); |
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189 | static int rtems_bsd_pipe_poll(rtems_libio_t *iop, int events); |
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190 | int rtems_bsd_pipe_kqfilter(rtems_libio_t *iop, struct knote *kn); |
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191 | |
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192 | static const rtems_filesystem_file_handlers_r pipeops = { |
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193 | .open_h = rtems_bsd_pipe_open, |
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194 | .close_h = rtems_bsd_pipe_close, |
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195 | .read_h = rtems_bsd_pipe_read, |
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196 | .write_h = rtems_bsd_pipe_write, |
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197 | .ioctl_h = rtems_bsd_pipe_ioctl, |
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198 | .lseek_h = rtems_filesystem_default_lseek, |
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199 | .fstat_h = rtems_bsd_pipe_stat, |
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200 | .ftruncate_h = rtems_filesystem_default_ftruncate, |
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201 | .fsync_h = rtems_filesystem_default_fsync_or_fdatasync, |
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202 | .fdatasync_h = rtems_filesystem_default_fsync_or_fdatasync, |
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203 | .fcntl_h = rtems_bsd_pipe_fcntl, |
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204 | .poll_h = rtems_bsd_pipe_poll, |
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205 | .kqfilter_h = rtems_bsd_pipe_kqfilter |
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206 | }; |
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207 | |
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208 | long maxpipekva; /* Limit on pipe KVA */ |
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209 | |
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210 | #endif /* __rtems__ */ |
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211 | |
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212 | static void filt_pipedetach(struct knote *kn); |
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213 | static void filt_pipedetach_notsup(struct knote *kn); |
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214 | static int filt_pipenotsup(struct knote *kn, long hint); |
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215 | static int filt_piperead(struct knote *kn, long hint); |
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216 | static int filt_pipewrite(struct knote *kn, long hint); |
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217 | |
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218 | static struct filterops pipe_nfiltops = { |
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219 | .f_isfd = 1, |
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220 | .f_detach = filt_pipedetach_notsup, |
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221 | .f_event = filt_pipenotsup |
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222 | }; |
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223 | static struct filterops pipe_rfiltops = { |
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224 | .f_isfd = 1, |
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225 | .f_detach = filt_pipedetach, |
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226 | .f_event = filt_piperead |
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227 | }; |
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228 | static struct filterops pipe_wfiltops = { |
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229 | .f_isfd = 1, |
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230 | .f_detach = filt_pipedetach, |
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231 | .f_event = filt_pipewrite |
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232 | }; |
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233 | |
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234 | /* |
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235 | * Default pipe buffer size(s), this can be kind-of large now because pipe |
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236 | * space is pageable. The pipe code will try to maintain locality of |
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237 | * reference for performance reasons, so small amounts of outstanding I/O |
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238 | * will not wipe the cache. |
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239 | */ |
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240 | #define MINPIPESIZE (PIPE_SIZE/3) |
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241 | #define MAXPIPESIZE (2*PIPE_SIZE/3) |
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242 | |
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243 | static long amountpipekva; |
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244 | static int pipefragretry; |
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245 | static int pipeallocfail; |
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246 | static int piperesizefail; |
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247 | static int piperesizeallowed = 1; |
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248 | |
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249 | SYSCTL_LONG(_kern_ipc, OID_AUTO, maxpipekva, CTLFLAG_RDTUN | CTLFLAG_NOFETCH, |
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250 | &maxpipekva, 0, "Pipe KVA limit"); |
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251 | SYSCTL_LONG(_kern_ipc, OID_AUTO, pipekva, CTLFLAG_RD, |
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252 | &amountpipekva, 0, "Pipe KVA usage"); |
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253 | SYSCTL_INT(_kern_ipc, OID_AUTO, pipefragretry, CTLFLAG_RD, |
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254 | &pipefragretry, 0, "Pipe allocation retries due to fragmentation"); |
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255 | SYSCTL_INT(_kern_ipc, OID_AUTO, pipeallocfail, CTLFLAG_RD, |
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256 | &pipeallocfail, 0, "Pipe allocation failures"); |
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257 | SYSCTL_INT(_kern_ipc, OID_AUTO, piperesizefail, CTLFLAG_RD, |
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258 | &piperesizefail, 0, "Pipe resize failures"); |
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259 | SYSCTL_INT(_kern_ipc, OID_AUTO, piperesizeallowed, CTLFLAG_RW, |
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260 | &piperesizeallowed, 0, "Pipe resizing allowed"); |
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261 | |
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262 | static void pipeinit(void *dummy __unused); |
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263 | static void pipeclose(struct pipe *cpipe); |
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264 | static void pipe_free_kmem(struct pipe *cpipe); |
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265 | static void pipe_create(struct pipe *pipe, int backing); |
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266 | static void pipe_paircreate(struct thread *td, struct pipepair **p_pp); |
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267 | static __inline int pipelock(struct pipe *cpipe, int catch); |
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268 | static __inline void pipeunlock(struct pipe *cpipe); |
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269 | #ifndef PIPE_NODIRECT |
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270 | static int pipe_build_write_buffer(struct pipe *wpipe, struct uio *uio); |
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271 | static void pipe_destroy_write_buffer(struct pipe *wpipe); |
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272 | static int pipe_direct_write(struct pipe *wpipe, struct uio *uio); |
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273 | static void pipe_clone_write_buffer(struct pipe *wpipe); |
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274 | #endif |
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275 | static int pipespace(struct pipe *cpipe, int size); |
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276 | static int pipespace_new(struct pipe *cpipe, int size); |
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277 | |
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278 | static int pipe_zone_ctor(void *mem, int size, void *arg, int flags); |
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279 | static int pipe_zone_init(void *mem, int size, int flags); |
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280 | static void pipe_zone_fini(void *mem, int size); |
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281 | |
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282 | static uma_zone_t pipe_zone; |
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283 | static struct unrhdr *pipeino_unr; |
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284 | static dev_t pipedev_ino; |
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285 | |
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286 | SYSINIT(vfs, SI_SUB_VFS, SI_ORDER_ANY, pipeinit, NULL); |
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287 | |
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288 | static void |
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289 | pipeinit(void *dummy __unused) |
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290 | { |
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291 | |
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292 | pipe_zone = uma_zcreate("pipe", sizeof(struct pipepair), |
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293 | pipe_zone_ctor, NULL, pipe_zone_init, pipe_zone_fini, |
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294 | UMA_ALIGN_PTR, 0); |
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295 | KASSERT(pipe_zone != NULL, ("pipe_zone not initialized")); |
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296 | pipeino_unr = new_unrhdr(1, INT32_MAX, NULL); |
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297 | KASSERT(pipeino_unr != NULL, ("pipe fake inodes not initialized")); |
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298 | pipedev_ino = devfs_alloc_cdp_inode(); |
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299 | KASSERT(pipedev_ino > 0, ("pipe dev inode not initialized")); |
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300 | } |
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301 | |
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302 | static int |
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303 | pipe_zone_ctor(void *mem, int size, void *arg, int flags) |
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304 | { |
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305 | struct pipepair *pp; |
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306 | struct pipe *rpipe, *wpipe; |
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307 | |
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308 | KASSERT(size == sizeof(*pp), ("pipe_zone_ctor: wrong size")); |
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309 | |
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310 | pp = (struct pipepair *)mem; |
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311 | |
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312 | /* |
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313 | * We zero both pipe endpoints to make sure all the kmem pointers |
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314 | * are NULL, flag fields are zero'd, etc. We timestamp both |
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315 | * endpoints with the same time. |
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316 | */ |
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317 | rpipe = &pp->pp_rpipe; |
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318 | bzero(rpipe, sizeof(*rpipe)); |
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319 | #ifndef __rtems__ |
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320 | vfs_timestamp(&rpipe->pipe_ctime); |
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321 | #else /* __rtems__ */ |
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322 | rpipe->pipe_ctime.tv_sec = time(NULL); |
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323 | #endif /* __rtems__ */ |
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324 | rpipe->pipe_atime = rpipe->pipe_mtime = rpipe->pipe_ctime; |
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325 | |
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326 | wpipe = &pp->pp_wpipe; |
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327 | bzero(wpipe, sizeof(*wpipe)); |
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328 | wpipe->pipe_ctime = rpipe->pipe_ctime; |
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329 | wpipe->pipe_atime = wpipe->pipe_mtime = rpipe->pipe_ctime; |
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330 | |
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331 | rpipe->pipe_peer = wpipe; |
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332 | rpipe->pipe_pair = pp; |
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333 | wpipe->pipe_peer = rpipe; |
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334 | wpipe->pipe_pair = pp; |
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335 | |
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336 | /* |
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337 | * Mark both endpoints as present; they will later get free'd |
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338 | * one at a time. When both are free'd, then the whole pair |
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339 | * is released. |
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340 | */ |
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341 | rpipe->pipe_present = PIPE_ACTIVE; |
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342 | wpipe->pipe_present = PIPE_ACTIVE; |
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343 | |
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344 | /* |
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345 | * Eventually, the MAC Framework may initialize the label |
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346 | * in ctor or init, but for now we do it elswhere to avoid |
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347 | * blocking in ctor or init. |
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348 | */ |
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349 | pp->pp_label = NULL; |
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350 | |
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351 | return (0); |
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352 | } |
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353 | |
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354 | static int |
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355 | pipe_zone_init(void *mem, int size, int flags) |
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356 | { |
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357 | struct pipepair *pp; |
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358 | |
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359 | KASSERT(size == sizeof(*pp), ("pipe_zone_init: wrong size")); |
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360 | |
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361 | pp = (struct pipepair *)mem; |
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362 | |
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363 | mtx_init(&pp->pp_mtx, "pipe mutex", NULL, MTX_DEF | MTX_NEW); |
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364 | return (0); |
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365 | } |
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366 | |
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367 | static void |
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368 | pipe_zone_fini(void *mem, int size) |
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369 | { |
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370 | struct pipepair *pp; |
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371 | |
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372 | KASSERT(size == sizeof(*pp), ("pipe_zone_fini: wrong size")); |
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373 | |
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374 | pp = (struct pipepair *)mem; |
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375 | |
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376 | mtx_destroy(&pp->pp_mtx); |
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377 | } |
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378 | |
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379 | static void |
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380 | pipe_paircreate(struct thread *td, struct pipepair **p_pp) |
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381 | { |
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382 | struct pipepair *pp; |
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383 | struct pipe *rpipe, *wpipe; |
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384 | |
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385 | *p_pp = pp = uma_zalloc(pipe_zone, M_WAITOK); |
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386 | #ifdef MAC |
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387 | /* |
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388 | * The MAC label is shared between the connected endpoints. As a |
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389 | * result mac_pipe_init() and mac_pipe_create() are called once |
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390 | * for the pair, and not on the endpoints. |
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391 | */ |
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392 | mac_pipe_init(pp); |
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393 | mac_pipe_create(td->td_ucred, pp); |
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394 | #endif |
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395 | rpipe = &pp->pp_rpipe; |
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396 | wpipe = &pp->pp_wpipe; |
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397 | |
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398 | knlist_init_mtx(&rpipe->pipe_sel.si_note, PIPE_MTX(rpipe)); |
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399 | knlist_init_mtx(&wpipe->pipe_sel.si_note, PIPE_MTX(wpipe)); |
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400 | |
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401 | /* Only the forward direction pipe is backed by default */ |
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402 | pipe_create(rpipe, 1); |
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403 | pipe_create(wpipe, 0); |
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404 | |
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405 | rpipe->pipe_state |= PIPE_DIRECTOK; |
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406 | wpipe->pipe_state |= PIPE_DIRECTOK; |
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407 | } |
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408 | |
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409 | void |
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410 | pipe_named_ctor(struct pipe **ppipe, struct thread *td) |
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411 | { |
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412 | struct pipepair *pp; |
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413 | |
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414 | pipe_paircreate(td, &pp); |
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415 | pp->pp_rpipe.pipe_state |= PIPE_NAMED; |
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416 | *ppipe = &pp->pp_rpipe; |
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417 | } |
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418 | |
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419 | void |
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420 | pipe_dtor(struct pipe *dpipe) |
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421 | { |
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422 | struct pipe *peer; |
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423 | ino_t ino; |
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424 | |
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425 | ino = dpipe->pipe_ino; |
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426 | peer = (dpipe->pipe_state & PIPE_NAMED) != 0 ? dpipe->pipe_peer : NULL; |
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427 | funsetown(&dpipe->pipe_sigio); |
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428 | pipeclose(dpipe); |
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429 | if (peer != NULL) { |
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430 | funsetown(&peer->pipe_sigio); |
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431 | pipeclose(peer); |
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432 | } |
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433 | if (ino != 0 && ino != (ino_t)-1) |
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434 | free_unr(pipeino_unr, ino); |
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435 | } |
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436 | |
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437 | /* |
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438 | * The pipe system call for the DTYPE_PIPE type of pipes. If we fail, let |
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439 | * the zone pick up the pieces via pipeclose(). |
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440 | */ |
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441 | int |
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442 | kern_pipe(struct thread *td, int fildes[2], int flags, struct filecaps *fcaps1, |
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443 | struct filecaps *fcaps2) |
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444 | { |
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445 | struct file *rf, *wf; |
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446 | struct pipe *rpipe, *wpipe; |
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447 | struct pipepair *pp; |
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448 | int fd, fflags, error; |
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449 | |
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450 | pipe_paircreate(td, &pp); |
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451 | rpipe = &pp->pp_rpipe; |
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452 | wpipe = &pp->pp_wpipe; |
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453 | error = falloc_caps(td, &rf, &fd, flags, fcaps1); |
---|
454 | if (error) { |
---|
455 | pipeclose(rpipe); |
---|
456 | pipeclose(wpipe); |
---|
457 | return (error); |
---|
458 | } |
---|
459 | /* An extra reference on `rf' has been held for us by falloc_caps(). */ |
---|
460 | fildes[0] = fd; |
---|
461 | |
---|
462 | fflags = FREAD | FWRITE; |
---|
463 | if ((flags & O_NONBLOCK) != 0) |
---|
464 | fflags |= FNONBLOCK; |
---|
465 | |
---|
466 | /* |
---|
467 | * Warning: once we've gotten past allocation of the fd for the |
---|
468 | * read-side, we can only drop the read side via fdrop() in order |
---|
469 | * to avoid races against processes which manage to dup() the read |
---|
470 | * side while we are blocked trying to allocate the write side. |
---|
471 | */ |
---|
472 | finit(rf, fflags, DTYPE_PIPE, rpipe, &pipeops); |
---|
473 | error = falloc_caps(td, &wf, &fd, flags, fcaps2); |
---|
474 | if (error) { |
---|
475 | fdclose(td, rf, fildes[0]); |
---|
476 | fdrop(rf, td); |
---|
477 | /* rpipe has been closed by fdrop(). */ |
---|
478 | pipeclose(wpipe); |
---|
479 | return (error); |
---|
480 | } |
---|
481 | /* An extra reference on `wf' has been held for us by falloc_caps(). */ |
---|
482 | finit(wf, fflags, DTYPE_PIPE, wpipe, &pipeops); |
---|
483 | fdrop(wf, td); |
---|
484 | fildes[1] = fd; |
---|
485 | fdrop(rf, td); |
---|
486 | |
---|
487 | return (0); |
---|
488 | } |
---|
489 | |
---|
490 | #ifdef COMPAT_FREEBSD10 |
---|
491 | /* ARGSUSED */ |
---|
492 | int |
---|
493 | freebsd10_pipe(struct thread *td, struct freebsd10_pipe_args *uap __unused) |
---|
494 | { |
---|
495 | int error; |
---|
496 | int fildes[2]; |
---|
497 | |
---|
498 | error = kern_pipe(td, fildes, 0, NULL, NULL); |
---|
499 | if (error) |
---|
500 | return (error); |
---|
501 | |
---|
502 | td->td_retval[0] = fildes[0]; |
---|
503 | td->td_retval[1] = fildes[1]; |
---|
504 | |
---|
505 | return (0); |
---|
506 | } |
---|
507 | #endif |
---|
508 | |
---|
509 | #ifndef __rtems__ |
---|
510 | int |
---|
511 | sys_pipe2(struct thread *td, struct pipe2_args *uap) |
---|
512 | { |
---|
513 | int error, fildes[2]; |
---|
514 | |
---|
515 | if (uap->flags & ~(O_CLOEXEC | O_NONBLOCK)) |
---|
516 | return (EINVAL); |
---|
517 | error = kern_pipe(td, fildes, uap->flags, NULL, NULL); |
---|
518 | if (error) |
---|
519 | return (error); |
---|
520 | error = copyout(fildes, uap->fildes, 2 * sizeof(int)); |
---|
521 | if (error) { |
---|
522 | (void)kern_close(td, fildes[0]); |
---|
523 | (void)kern_close(td, fildes[1]); |
---|
524 | } |
---|
525 | return (error); |
---|
526 | } |
---|
527 | #endif /* __rtems__ */ |
---|
528 | |
---|
529 | #ifdef __rtems__ |
---|
530 | int |
---|
531 | pipe(int fildes[2]) |
---|
532 | { |
---|
533 | struct thread *td = rtems_bsd_get_curthread_or_null(); |
---|
534 | int error; |
---|
535 | |
---|
536 | if (td != NULL) { |
---|
537 | error = kern_pipe(td, fildes, 0, NULL, NULL); |
---|
538 | } else { |
---|
539 | error = ENOMEM; |
---|
540 | } |
---|
541 | |
---|
542 | if (error == 0) { |
---|
543 | return error; |
---|
544 | } else { |
---|
545 | rtems_set_errno_and_return_minus_one(error); |
---|
546 | } |
---|
547 | } |
---|
548 | #endif /* __rtems__ */ |
---|
549 | |
---|
550 | /* |
---|
551 | * Allocate kva for pipe circular buffer, the space is pageable |
---|
552 | * This routine will 'realloc' the size of a pipe safely, if it fails |
---|
553 | * it will retain the old buffer. |
---|
554 | * If it fails it will return ENOMEM. |
---|
555 | */ |
---|
556 | static int |
---|
557 | pipespace_new(cpipe, size) |
---|
558 | struct pipe *cpipe; |
---|
559 | int size; |
---|
560 | { |
---|
561 | caddr_t buffer; |
---|
562 | int error, cnt, firstseg; |
---|
563 | static int curfail = 0; |
---|
564 | static struct timeval lastfail; |
---|
565 | |
---|
566 | KASSERT(!mtx_owned(PIPE_MTX(cpipe)), ("pipespace: pipe mutex locked")); |
---|
567 | KASSERT(!(cpipe->pipe_state & PIPE_DIRECTW), |
---|
568 | ("pipespace: resize of direct writes not allowed")); |
---|
569 | retry: |
---|
570 | cnt = cpipe->pipe_buffer.cnt; |
---|
571 | if (cnt > size) |
---|
572 | size = cnt; |
---|
573 | |
---|
574 | size = round_page(size); |
---|
575 | #ifndef __rtems__ |
---|
576 | buffer = (caddr_t) vm_map_min(pipe_map); |
---|
577 | |
---|
578 | error = vm_map_find(pipe_map, NULL, 0, |
---|
579 | (vm_offset_t *) &buffer, size, 0, VMFS_ANY_SPACE, |
---|
580 | VM_PROT_ALL, VM_PROT_ALL, 0); |
---|
581 | if (error != KERN_SUCCESS) { |
---|
582 | #else /* __rtems__ */ |
---|
583 | (void)error; |
---|
584 | buffer = malloc(size, M_TEMP, M_WAITOK | M_ZERO); |
---|
585 | if (buffer == NULL) { |
---|
586 | #endif /* __rtems__ */ |
---|
587 | if ((cpipe->pipe_buffer.buffer == NULL) && |
---|
588 | (size > SMALL_PIPE_SIZE)) { |
---|
589 | size = SMALL_PIPE_SIZE; |
---|
590 | pipefragretry++; |
---|
591 | goto retry; |
---|
592 | } |
---|
593 | if (cpipe->pipe_buffer.buffer == NULL) { |
---|
594 | pipeallocfail++; |
---|
595 | if (ppsratecheck(&lastfail, &curfail, 1)) |
---|
596 | printf("kern.ipc.maxpipekva exceeded; see tuning(7)\n"); |
---|
597 | } else { |
---|
598 | piperesizefail++; |
---|
599 | } |
---|
600 | return (ENOMEM); |
---|
601 | } |
---|
602 | |
---|
603 | /* copy data, then free old resources if we're resizing */ |
---|
604 | if (cnt > 0) { |
---|
605 | if (cpipe->pipe_buffer.in <= cpipe->pipe_buffer.out) { |
---|
606 | firstseg = cpipe->pipe_buffer.size - cpipe->pipe_buffer.out; |
---|
607 | bcopy(&cpipe->pipe_buffer.buffer[cpipe->pipe_buffer.out], |
---|
608 | buffer, firstseg); |
---|
609 | if ((cnt - firstseg) > 0) |
---|
610 | bcopy(cpipe->pipe_buffer.buffer, &buffer[firstseg], |
---|
611 | cpipe->pipe_buffer.in); |
---|
612 | } else { |
---|
613 | bcopy(&cpipe->pipe_buffer.buffer[cpipe->pipe_buffer.out], |
---|
614 | buffer, cnt); |
---|
615 | } |
---|
616 | } |
---|
617 | pipe_free_kmem(cpipe); |
---|
618 | cpipe->pipe_buffer.buffer = buffer; |
---|
619 | cpipe->pipe_buffer.size = size; |
---|
620 | cpipe->pipe_buffer.in = cnt; |
---|
621 | cpipe->pipe_buffer.out = 0; |
---|
622 | cpipe->pipe_buffer.cnt = cnt; |
---|
623 | atomic_add_long(&amountpipekva, cpipe->pipe_buffer.size); |
---|
624 | return (0); |
---|
625 | } |
---|
626 | |
---|
627 | /* |
---|
628 | * Wrapper for pipespace_new() that performs locking assertions. |
---|
629 | */ |
---|
630 | static int |
---|
631 | pipespace(cpipe, size) |
---|
632 | struct pipe *cpipe; |
---|
633 | int size; |
---|
634 | { |
---|
635 | |
---|
636 | KASSERT(cpipe->pipe_state & PIPE_LOCKFL, |
---|
637 | ("Unlocked pipe passed to pipespace")); |
---|
638 | return (pipespace_new(cpipe, size)); |
---|
639 | } |
---|
640 | |
---|
641 | /* |
---|
642 | * lock a pipe for I/O, blocking other access |
---|
643 | */ |
---|
644 | static __inline int |
---|
645 | pipelock(cpipe, catch) |
---|
646 | struct pipe *cpipe; |
---|
647 | int catch; |
---|
648 | { |
---|
649 | int error; |
---|
650 | |
---|
651 | PIPE_LOCK_ASSERT(cpipe, MA_OWNED); |
---|
652 | while (cpipe->pipe_state & PIPE_LOCKFL) { |
---|
653 | cpipe->pipe_state |= PIPE_LWANT; |
---|
654 | error = msleep(cpipe, PIPE_MTX(cpipe), |
---|
655 | catch ? (PRIBIO | PCATCH) : PRIBIO, |
---|
656 | "pipelk", 0); |
---|
657 | if (error != 0) |
---|
658 | return (error); |
---|
659 | } |
---|
660 | cpipe->pipe_state |= PIPE_LOCKFL; |
---|
661 | return (0); |
---|
662 | } |
---|
663 | |
---|
664 | /* |
---|
665 | * unlock a pipe I/O lock |
---|
666 | */ |
---|
667 | static __inline void |
---|
668 | pipeunlock(cpipe) |
---|
669 | struct pipe *cpipe; |
---|
670 | { |
---|
671 | |
---|
672 | PIPE_LOCK_ASSERT(cpipe, MA_OWNED); |
---|
673 | KASSERT(cpipe->pipe_state & PIPE_LOCKFL, |
---|
674 | ("Unlocked pipe passed to pipeunlock")); |
---|
675 | cpipe->pipe_state &= ~PIPE_LOCKFL; |
---|
676 | if (cpipe->pipe_state & PIPE_LWANT) { |
---|
677 | cpipe->pipe_state &= ~PIPE_LWANT; |
---|
678 | wakeup(cpipe); |
---|
679 | } |
---|
680 | } |
---|
681 | |
---|
682 | void |
---|
683 | pipeselwakeup(cpipe) |
---|
684 | struct pipe *cpipe; |
---|
685 | { |
---|
686 | |
---|
687 | PIPE_LOCK_ASSERT(cpipe, MA_OWNED); |
---|
688 | if (cpipe->pipe_state & PIPE_SEL) { |
---|
689 | selwakeuppri(&cpipe->pipe_sel, PSOCK); |
---|
690 | if (!SEL_WAITING(&cpipe->pipe_sel)) |
---|
691 | cpipe->pipe_state &= ~PIPE_SEL; |
---|
692 | } |
---|
693 | #ifndef __rtems__ |
---|
694 | if ((cpipe->pipe_state & PIPE_ASYNC) && cpipe->pipe_sigio) |
---|
695 | pgsigio(&cpipe->pipe_sigio, SIGIO, 0); |
---|
696 | #endif /* __rtems__ */ |
---|
697 | KNOTE_LOCKED(&cpipe->pipe_sel.si_note, 0); |
---|
698 | } |
---|
699 | |
---|
700 | /* |
---|
701 | * Initialize and allocate VM and memory for pipe. The structure |
---|
702 | * will start out zero'd from the ctor, so we just manage the kmem. |
---|
703 | */ |
---|
704 | static void |
---|
705 | pipe_create(pipe, backing) |
---|
706 | struct pipe *pipe; |
---|
707 | int backing; |
---|
708 | { |
---|
709 | |
---|
710 | if (backing) { |
---|
711 | /* |
---|
712 | * Note that these functions can fail if pipe map is exhausted |
---|
713 | * (as a result of too many pipes created), but we ignore the |
---|
714 | * error as it is not fatal and could be provoked by |
---|
715 | * unprivileged users. The only consequence is worse performance |
---|
716 | * with given pipe. |
---|
717 | */ |
---|
718 | if (amountpipekva > maxpipekva / 2) |
---|
719 | (void)pipespace_new(pipe, SMALL_PIPE_SIZE); |
---|
720 | else |
---|
721 | (void)pipespace_new(pipe, PIPE_SIZE); |
---|
722 | } |
---|
723 | |
---|
724 | pipe->pipe_ino = -1; |
---|
725 | } |
---|
726 | |
---|
727 | /* ARGSUSED */ |
---|
728 | static int |
---|
729 | pipe_read(fp, uio, active_cred, flags, td) |
---|
730 | struct file *fp; |
---|
731 | struct uio *uio; |
---|
732 | struct ucred *active_cred; |
---|
733 | struct thread *td; |
---|
734 | int flags; |
---|
735 | { |
---|
736 | struct pipe *rpipe; |
---|
737 | int error; |
---|
738 | int nread = 0; |
---|
739 | int size; |
---|
740 | |
---|
741 | rpipe = fp->f_data; |
---|
742 | PIPE_LOCK(rpipe); |
---|
743 | ++rpipe->pipe_busy; |
---|
744 | error = pipelock(rpipe, 1); |
---|
745 | if (error) |
---|
746 | goto unlocked_error; |
---|
747 | |
---|
748 | #ifdef MAC |
---|
749 | error = mac_pipe_check_read(active_cred, rpipe->pipe_pair); |
---|
750 | if (error) |
---|
751 | goto locked_error; |
---|
752 | #endif |
---|
753 | if (amountpipekva > (3 * maxpipekva) / 4) { |
---|
754 | if (!(rpipe->pipe_state & PIPE_DIRECTW) && |
---|
755 | (rpipe->pipe_buffer.size > SMALL_PIPE_SIZE) && |
---|
756 | (rpipe->pipe_buffer.cnt <= SMALL_PIPE_SIZE) && |
---|
757 | (piperesizeallowed == 1)) { |
---|
758 | PIPE_UNLOCK(rpipe); |
---|
759 | pipespace(rpipe, SMALL_PIPE_SIZE); |
---|
760 | PIPE_LOCK(rpipe); |
---|
761 | } |
---|
762 | } |
---|
763 | |
---|
764 | while (uio->uio_resid) { |
---|
765 | /* |
---|
766 | * normal pipe buffer receive |
---|
767 | */ |
---|
768 | if (rpipe->pipe_buffer.cnt > 0) { |
---|
769 | size = rpipe->pipe_buffer.size - rpipe->pipe_buffer.out; |
---|
770 | if (size > rpipe->pipe_buffer.cnt) |
---|
771 | size = rpipe->pipe_buffer.cnt; |
---|
772 | if (size > uio->uio_resid) |
---|
773 | size = uio->uio_resid; |
---|
774 | |
---|
775 | PIPE_UNLOCK(rpipe); |
---|
776 | error = uiomove( |
---|
777 | &rpipe->pipe_buffer.buffer[rpipe->pipe_buffer.out], |
---|
778 | size, uio); |
---|
779 | PIPE_LOCK(rpipe); |
---|
780 | if (error) |
---|
781 | break; |
---|
782 | |
---|
783 | rpipe->pipe_buffer.out += size; |
---|
784 | if (rpipe->pipe_buffer.out >= rpipe->pipe_buffer.size) |
---|
785 | rpipe->pipe_buffer.out = 0; |
---|
786 | |
---|
787 | rpipe->pipe_buffer.cnt -= size; |
---|
788 | |
---|
789 | /* |
---|
790 | * If there is no more to read in the pipe, reset |
---|
791 | * its pointers to the beginning. This improves |
---|
792 | * cache hit stats. |
---|
793 | */ |
---|
794 | if (rpipe->pipe_buffer.cnt == 0) { |
---|
795 | rpipe->pipe_buffer.in = 0; |
---|
796 | rpipe->pipe_buffer.out = 0; |
---|
797 | } |
---|
798 | nread += size; |
---|
799 | #ifndef PIPE_NODIRECT |
---|
800 | /* |
---|
801 | * Direct copy, bypassing a kernel buffer. |
---|
802 | */ |
---|
803 | } else if ((size = rpipe->pipe_map.cnt) && |
---|
804 | (rpipe->pipe_state & PIPE_DIRECTW)) { |
---|
805 | if (size > uio->uio_resid) |
---|
806 | size = (u_int) uio->uio_resid; |
---|
807 | |
---|
808 | PIPE_UNLOCK(rpipe); |
---|
809 | error = uiomove_fromphys(rpipe->pipe_map.ms, |
---|
810 | rpipe->pipe_map.pos, size, uio); |
---|
811 | PIPE_LOCK(rpipe); |
---|
812 | if (error) |
---|
813 | break; |
---|
814 | nread += size; |
---|
815 | rpipe->pipe_map.pos += size; |
---|
816 | rpipe->pipe_map.cnt -= size; |
---|
817 | if (rpipe->pipe_map.cnt == 0) { |
---|
818 | rpipe->pipe_state &= ~(PIPE_DIRECTW|PIPE_WANTW); |
---|
819 | wakeup(rpipe); |
---|
820 | } |
---|
821 | #endif |
---|
822 | } else { |
---|
823 | /* |
---|
824 | * detect EOF condition |
---|
825 | * read returns 0 on EOF, no need to set error |
---|
826 | */ |
---|
827 | if (rpipe->pipe_state & PIPE_EOF) |
---|
828 | break; |
---|
829 | |
---|
830 | /* |
---|
831 | * If the "write-side" has been blocked, wake it up now. |
---|
832 | */ |
---|
833 | if (rpipe->pipe_state & PIPE_WANTW) { |
---|
834 | rpipe->pipe_state &= ~PIPE_WANTW; |
---|
835 | wakeup(rpipe); |
---|
836 | } |
---|
837 | |
---|
838 | /* |
---|
839 | * Break if some data was read. |
---|
840 | */ |
---|
841 | if (nread > 0) |
---|
842 | break; |
---|
843 | |
---|
844 | /* |
---|
845 | * Unlock the pipe buffer for our remaining processing. |
---|
846 | * We will either break out with an error or we will |
---|
847 | * sleep and relock to loop. |
---|
848 | */ |
---|
849 | pipeunlock(rpipe); |
---|
850 | |
---|
851 | /* |
---|
852 | * Handle non-blocking mode operation or |
---|
853 | * wait for more data. |
---|
854 | */ |
---|
855 | #ifndef __rtems__ |
---|
856 | if (fp->f_flag & FNONBLOCK) { |
---|
857 | #else /* __rtems__ */ |
---|
858 | if (rtems_bsd_libio_flags_to_fflag(fp->f_io.flags) & FNONBLOCK) { |
---|
859 | #endif /* __rtems__ */ |
---|
860 | error = EAGAIN; |
---|
861 | } else { |
---|
862 | rpipe->pipe_state |= PIPE_WANTR; |
---|
863 | if ((error = msleep(rpipe, PIPE_MTX(rpipe), |
---|
864 | PRIBIO | PCATCH, |
---|
865 | "piperd", 0)) == 0) |
---|
866 | error = pipelock(rpipe, 1); |
---|
867 | } |
---|
868 | if (error) |
---|
869 | goto unlocked_error; |
---|
870 | } |
---|
871 | } |
---|
872 | #ifdef MAC |
---|
873 | locked_error: |
---|
874 | #endif |
---|
875 | pipeunlock(rpipe); |
---|
876 | |
---|
877 | /* XXX: should probably do this before getting any locks. */ |
---|
878 | if (error == 0) |
---|
879 | #ifndef __rtems__ |
---|
880 | vfs_timestamp(&rpipe->pipe_atime); |
---|
881 | #else /* __rtems__ */ |
---|
882 | rpipe->pipe_atime.tv_sec = time(NULL); |
---|
883 | #endif /* __rtems__ */ |
---|
884 | unlocked_error: |
---|
885 | --rpipe->pipe_busy; |
---|
886 | |
---|
887 | /* |
---|
888 | * PIPE_WANT processing only makes sense if pipe_busy is 0. |
---|
889 | */ |
---|
890 | if ((rpipe->pipe_busy == 0) && (rpipe->pipe_state & PIPE_WANT)) { |
---|
891 | rpipe->pipe_state &= ~(PIPE_WANT|PIPE_WANTW); |
---|
892 | wakeup(rpipe); |
---|
893 | } else if (rpipe->pipe_buffer.cnt < MINPIPESIZE) { |
---|
894 | /* |
---|
895 | * Handle write blocking hysteresis. |
---|
896 | */ |
---|
897 | if (rpipe->pipe_state & PIPE_WANTW) { |
---|
898 | rpipe->pipe_state &= ~PIPE_WANTW; |
---|
899 | wakeup(rpipe); |
---|
900 | } |
---|
901 | } |
---|
902 | |
---|
903 | if ((rpipe->pipe_buffer.size - rpipe->pipe_buffer.cnt) >= PIPE_BUF) |
---|
904 | pipeselwakeup(rpipe); |
---|
905 | |
---|
906 | PIPE_UNLOCK(rpipe); |
---|
907 | return (error); |
---|
908 | } |
---|
909 | #ifdef __rtems__ |
---|
910 | static ssize_t |
---|
911 | rtems_bsd_pipe_read(rtems_libio_t *iop, void *buffer, size_t count) |
---|
912 | { |
---|
913 | struct thread *td = rtems_bsd_get_curthread_or_null(); |
---|
914 | struct file *fp = rtems_bsd_iop_to_fp(iop); |
---|
915 | struct iovec iov = { |
---|
916 | .iov_base = buffer, |
---|
917 | .iov_len = count |
---|
918 | }; |
---|
919 | struct uio auio = { |
---|
920 | .uio_iov = &iov, |
---|
921 | .uio_iovcnt = 1, |
---|
922 | .uio_offset = 0, |
---|
923 | .uio_resid = count, |
---|
924 | .uio_segflg = UIO_USERSPACE, |
---|
925 | .uio_rw = UIO_READ, |
---|
926 | .uio_td = td |
---|
927 | }; |
---|
928 | int error; |
---|
929 | |
---|
930 | if (td != NULL) { |
---|
931 | error = pipe_read(fp, &auio, NULL, 0, NULL); |
---|
932 | } else { |
---|
933 | error = ENOMEM; |
---|
934 | } |
---|
935 | |
---|
936 | if (error == 0) { |
---|
937 | return (count - auio.uio_resid); |
---|
938 | } else { |
---|
939 | rtems_set_errno_and_return_minus_one(error); |
---|
940 | } |
---|
941 | } |
---|
942 | #endif /* __rtems__ */ |
---|
943 | |
---|
944 | #ifndef PIPE_NODIRECT |
---|
945 | /* |
---|
946 | * Map the sending processes' buffer into kernel space and wire it. |
---|
947 | * This is similar to a physical write operation. |
---|
948 | */ |
---|
949 | static int |
---|
950 | pipe_build_write_buffer(wpipe, uio) |
---|
951 | struct pipe *wpipe; |
---|
952 | struct uio *uio; |
---|
953 | { |
---|
954 | u_int size; |
---|
955 | int i; |
---|
956 | |
---|
957 | PIPE_LOCK_ASSERT(wpipe, MA_NOTOWNED); |
---|
958 | KASSERT(wpipe->pipe_state & PIPE_DIRECTW, |
---|
959 | ("Clone attempt on non-direct write pipe!")); |
---|
960 | |
---|
961 | if (uio->uio_iov->iov_len > wpipe->pipe_buffer.size) |
---|
962 | size = wpipe->pipe_buffer.size; |
---|
963 | else |
---|
964 | size = uio->uio_iov->iov_len; |
---|
965 | |
---|
966 | if ((i = vm_fault_quick_hold_pages(&curproc->p_vmspace->vm_map, |
---|
967 | (vm_offset_t)uio->uio_iov->iov_base, size, VM_PROT_READ, |
---|
968 | wpipe->pipe_map.ms, PIPENPAGES)) < 0) |
---|
969 | return (EFAULT); |
---|
970 | |
---|
971 | /* |
---|
972 | * set up the control block |
---|
973 | */ |
---|
974 | wpipe->pipe_map.npages = i; |
---|
975 | wpipe->pipe_map.pos = |
---|
976 | ((vm_offset_t) uio->uio_iov->iov_base) & PAGE_MASK; |
---|
977 | wpipe->pipe_map.cnt = size; |
---|
978 | |
---|
979 | /* |
---|
980 | * and update the uio data |
---|
981 | */ |
---|
982 | |
---|
983 | uio->uio_iov->iov_len -= size; |
---|
984 | uio->uio_iov->iov_base = (char *)uio->uio_iov->iov_base + size; |
---|
985 | if (uio->uio_iov->iov_len == 0) |
---|
986 | uio->uio_iov++; |
---|
987 | uio->uio_resid -= size; |
---|
988 | uio->uio_offset += size; |
---|
989 | return (0); |
---|
990 | } |
---|
991 | |
---|
992 | /* |
---|
993 | * unmap and unwire the process buffer |
---|
994 | */ |
---|
995 | static void |
---|
996 | pipe_destroy_write_buffer(wpipe) |
---|
997 | struct pipe *wpipe; |
---|
998 | { |
---|
999 | |
---|
1000 | PIPE_LOCK_ASSERT(wpipe, MA_OWNED); |
---|
1001 | vm_page_unhold_pages(wpipe->pipe_map.ms, wpipe->pipe_map.npages); |
---|
1002 | wpipe->pipe_map.npages = 0; |
---|
1003 | } |
---|
1004 | |
---|
1005 | /* |
---|
1006 | * In the case of a signal, the writing process might go away. This |
---|
1007 | * code copies the data into the circular buffer so that the source |
---|
1008 | * pages can be freed without loss of data. |
---|
1009 | */ |
---|
1010 | static void |
---|
1011 | pipe_clone_write_buffer(wpipe) |
---|
1012 | struct pipe *wpipe; |
---|
1013 | { |
---|
1014 | struct uio uio; |
---|
1015 | struct iovec iov; |
---|
1016 | int size; |
---|
1017 | int pos; |
---|
1018 | |
---|
1019 | PIPE_LOCK_ASSERT(wpipe, MA_OWNED); |
---|
1020 | size = wpipe->pipe_map.cnt; |
---|
1021 | pos = wpipe->pipe_map.pos; |
---|
1022 | |
---|
1023 | wpipe->pipe_buffer.in = size; |
---|
1024 | wpipe->pipe_buffer.out = 0; |
---|
1025 | wpipe->pipe_buffer.cnt = size; |
---|
1026 | wpipe->pipe_state &= ~PIPE_DIRECTW; |
---|
1027 | |
---|
1028 | PIPE_UNLOCK(wpipe); |
---|
1029 | iov.iov_base = wpipe->pipe_buffer.buffer; |
---|
1030 | iov.iov_len = size; |
---|
1031 | uio.uio_iov = &iov; |
---|
1032 | uio.uio_iovcnt = 1; |
---|
1033 | uio.uio_offset = 0; |
---|
1034 | uio.uio_resid = size; |
---|
1035 | uio.uio_segflg = UIO_SYSSPACE; |
---|
1036 | uio.uio_rw = UIO_READ; |
---|
1037 | uio.uio_td = curthread; |
---|
1038 | uiomove_fromphys(wpipe->pipe_map.ms, pos, size, &uio); |
---|
1039 | PIPE_LOCK(wpipe); |
---|
1040 | pipe_destroy_write_buffer(wpipe); |
---|
1041 | } |
---|
1042 | |
---|
1043 | /* |
---|
1044 | * This implements the pipe buffer write mechanism. Note that only |
---|
1045 | * a direct write OR a normal pipe write can be pending at any given time. |
---|
1046 | * If there are any characters in the pipe buffer, the direct write will |
---|
1047 | * be deferred until the receiving process grabs all of the bytes from |
---|
1048 | * the pipe buffer. Then the direct mapping write is set-up. |
---|
1049 | */ |
---|
1050 | static int |
---|
1051 | pipe_direct_write(wpipe, uio) |
---|
1052 | struct pipe *wpipe; |
---|
1053 | struct uio *uio; |
---|
1054 | { |
---|
1055 | int error; |
---|
1056 | |
---|
1057 | retry: |
---|
1058 | PIPE_LOCK_ASSERT(wpipe, MA_OWNED); |
---|
1059 | error = pipelock(wpipe, 1); |
---|
1060 | if (error != 0) |
---|
1061 | goto error1; |
---|
1062 | if ((wpipe->pipe_state & PIPE_EOF) != 0) { |
---|
1063 | error = EPIPE; |
---|
1064 | pipeunlock(wpipe); |
---|
1065 | goto error1; |
---|
1066 | } |
---|
1067 | while (wpipe->pipe_state & PIPE_DIRECTW) { |
---|
1068 | if (wpipe->pipe_state & PIPE_WANTR) { |
---|
1069 | wpipe->pipe_state &= ~PIPE_WANTR; |
---|
1070 | wakeup(wpipe); |
---|
1071 | } |
---|
1072 | pipeselwakeup(wpipe); |
---|
1073 | wpipe->pipe_state |= PIPE_WANTW; |
---|
1074 | pipeunlock(wpipe); |
---|
1075 | error = msleep(wpipe, PIPE_MTX(wpipe), |
---|
1076 | PRIBIO | PCATCH, "pipdww", 0); |
---|
1077 | if (error) |
---|
1078 | goto error1; |
---|
1079 | else |
---|
1080 | goto retry; |
---|
1081 | } |
---|
1082 | wpipe->pipe_map.cnt = 0; /* transfer not ready yet */ |
---|
1083 | if (wpipe->pipe_buffer.cnt > 0) { |
---|
1084 | if (wpipe->pipe_state & PIPE_WANTR) { |
---|
1085 | wpipe->pipe_state &= ~PIPE_WANTR; |
---|
1086 | wakeup(wpipe); |
---|
1087 | } |
---|
1088 | pipeselwakeup(wpipe); |
---|
1089 | wpipe->pipe_state |= PIPE_WANTW; |
---|
1090 | pipeunlock(wpipe); |
---|
1091 | error = msleep(wpipe, PIPE_MTX(wpipe), |
---|
1092 | PRIBIO | PCATCH, "pipdwc", 0); |
---|
1093 | if (error) |
---|
1094 | goto error1; |
---|
1095 | else |
---|
1096 | goto retry; |
---|
1097 | } |
---|
1098 | |
---|
1099 | wpipe->pipe_state |= PIPE_DIRECTW; |
---|
1100 | |
---|
1101 | PIPE_UNLOCK(wpipe); |
---|
1102 | error = pipe_build_write_buffer(wpipe, uio); |
---|
1103 | PIPE_LOCK(wpipe); |
---|
1104 | if (error) { |
---|
1105 | wpipe->pipe_state &= ~PIPE_DIRECTW; |
---|
1106 | pipeunlock(wpipe); |
---|
1107 | goto error1; |
---|
1108 | } |
---|
1109 | |
---|
1110 | error = 0; |
---|
1111 | while (!error && (wpipe->pipe_state & PIPE_DIRECTW)) { |
---|
1112 | if (wpipe->pipe_state & PIPE_EOF) { |
---|
1113 | pipe_destroy_write_buffer(wpipe); |
---|
1114 | pipeselwakeup(wpipe); |
---|
1115 | pipeunlock(wpipe); |
---|
1116 | error = EPIPE; |
---|
1117 | goto error1; |
---|
1118 | } |
---|
1119 | if (wpipe->pipe_state & PIPE_WANTR) { |
---|
1120 | wpipe->pipe_state &= ~PIPE_WANTR; |
---|
1121 | wakeup(wpipe); |
---|
1122 | } |
---|
1123 | pipeselwakeup(wpipe); |
---|
1124 | wpipe->pipe_state |= PIPE_WANTW; |
---|
1125 | pipeunlock(wpipe); |
---|
1126 | error = msleep(wpipe, PIPE_MTX(wpipe), PRIBIO | PCATCH, |
---|
1127 | "pipdwt", 0); |
---|
1128 | pipelock(wpipe, 0); |
---|
1129 | } |
---|
1130 | |
---|
1131 | if (wpipe->pipe_state & PIPE_EOF) |
---|
1132 | error = EPIPE; |
---|
1133 | if (wpipe->pipe_state & PIPE_DIRECTW) { |
---|
1134 | /* |
---|
1135 | * this bit of trickery substitutes a kernel buffer for |
---|
1136 | * the process that might be going away. |
---|
1137 | */ |
---|
1138 | pipe_clone_write_buffer(wpipe); |
---|
1139 | } else { |
---|
1140 | pipe_destroy_write_buffer(wpipe); |
---|
1141 | } |
---|
1142 | pipeunlock(wpipe); |
---|
1143 | return (error); |
---|
1144 | |
---|
1145 | error1: |
---|
1146 | wakeup(wpipe); |
---|
1147 | return (error); |
---|
1148 | } |
---|
1149 | #endif |
---|
1150 | |
---|
1151 | static int |
---|
1152 | pipe_write(fp, uio, active_cred, flags, td) |
---|
1153 | struct file *fp; |
---|
1154 | struct uio *uio; |
---|
1155 | struct ucred *active_cred; |
---|
1156 | struct thread *td; |
---|
1157 | int flags; |
---|
1158 | { |
---|
1159 | int error = 0; |
---|
1160 | int desiredsize; |
---|
1161 | ssize_t orig_resid; |
---|
1162 | struct pipe *wpipe, *rpipe; |
---|
1163 | |
---|
1164 | rpipe = fp->f_data; |
---|
1165 | wpipe = PIPE_PEER(rpipe); |
---|
1166 | PIPE_LOCK(rpipe); |
---|
1167 | error = pipelock(wpipe, 1); |
---|
1168 | if (error) { |
---|
1169 | PIPE_UNLOCK(rpipe); |
---|
1170 | return (error); |
---|
1171 | } |
---|
1172 | /* |
---|
1173 | * detect loss of pipe read side, issue SIGPIPE if lost. |
---|
1174 | */ |
---|
1175 | if (wpipe->pipe_present != PIPE_ACTIVE || |
---|
1176 | (wpipe->pipe_state & PIPE_EOF)) { |
---|
1177 | pipeunlock(wpipe); |
---|
1178 | PIPE_UNLOCK(rpipe); |
---|
1179 | return (EPIPE); |
---|
1180 | } |
---|
1181 | #ifdef MAC |
---|
1182 | error = mac_pipe_check_write(active_cred, wpipe->pipe_pair); |
---|
1183 | if (error) { |
---|
1184 | pipeunlock(wpipe); |
---|
1185 | PIPE_UNLOCK(rpipe); |
---|
1186 | return (error); |
---|
1187 | } |
---|
1188 | #endif |
---|
1189 | ++wpipe->pipe_busy; |
---|
1190 | |
---|
1191 | /* Choose a larger size if it's advantageous */ |
---|
1192 | desiredsize = max(SMALL_PIPE_SIZE, wpipe->pipe_buffer.size); |
---|
1193 | while (desiredsize < wpipe->pipe_buffer.cnt + uio->uio_resid) { |
---|
1194 | if (piperesizeallowed != 1) |
---|
1195 | break; |
---|
1196 | if (amountpipekva > maxpipekva / 2) |
---|
1197 | break; |
---|
1198 | if (desiredsize == BIG_PIPE_SIZE) |
---|
1199 | break; |
---|
1200 | desiredsize = desiredsize * 2; |
---|
1201 | } |
---|
1202 | |
---|
1203 | /* Choose a smaller size if we're in a OOM situation */ |
---|
1204 | if ((amountpipekva > (3 * maxpipekva) / 4) && |
---|
1205 | (wpipe->pipe_buffer.size > SMALL_PIPE_SIZE) && |
---|
1206 | (wpipe->pipe_buffer.cnt <= SMALL_PIPE_SIZE) && |
---|
1207 | (piperesizeallowed == 1)) |
---|
1208 | desiredsize = SMALL_PIPE_SIZE; |
---|
1209 | |
---|
1210 | /* Resize if the above determined that a new size was necessary */ |
---|
1211 | if ((desiredsize != wpipe->pipe_buffer.size) && |
---|
1212 | ((wpipe->pipe_state & PIPE_DIRECTW) == 0)) { |
---|
1213 | PIPE_UNLOCK(wpipe); |
---|
1214 | pipespace(wpipe, desiredsize); |
---|
1215 | PIPE_LOCK(wpipe); |
---|
1216 | } |
---|
1217 | if (wpipe->pipe_buffer.size == 0) { |
---|
1218 | /* |
---|
1219 | * This can only happen for reverse direction use of pipes |
---|
1220 | * in a complete OOM situation. |
---|
1221 | */ |
---|
1222 | error = ENOMEM; |
---|
1223 | --wpipe->pipe_busy; |
---|
1224 | pipeunlock(wpipe); |
---|
1225 | PIPE_UNLOCK(wpipe); |
---|
1226 | return (error); |
---|
1227 | } |
---|
1228 | |
---|
1229 | pipeunlock(wpipe); |
---|
1230 | |
---|
1231 | orig_resid = uio->uio_resid; |
---|
1232 | |
---|
1233 | while (uio->uio_resid) { |
---|
1234 | int space; |
---|
1235 | |
---|
1236 | pipelock(wpipe, 0); |
---|
1237 | if (wpipe->pipe_state & PIPE_EOF) { |
---|
1238 | pipeunlock(wpipe); |
---|
1239 | error = EPIPE; |
---|
1240 | break; |
---|
1241 | } |
---|
1242 | #ifndef PIPE_NODIRECT |
---|
1243 | /* |
---|
1244 | * If the transfer is large, we can gain performance if |
---|
1245 | * we do process-to-process copies directly. |
---|
1246 | * If the write is non-blocking, we don't use the |
---|
1247 | * direct write mechanism. |
---|
1248 | * |
---|
1249 | * The direct write mechanism will detect the reader going |
---|
1250 | * away on us. |
---|
1251 | */ |
---|
1252 | if (uio->uio_segflg == UIO_USERSPACE && |
---|
1253 | uio->uio_iov->iov_len >= PIPE_MINDIRECT && |
---|
1254 | wpipe->pipe_buffer.size >= PIPE_MINDIRECT && |
---|
1255 | (fp->f_flag & FNONBLOCK) == 0) { |
---|
1256 | pipeunlock(wpipe); |
---|
1257 | error = pipe_direct_write(wpipe, uio); |
---|
1258 | if (error) |
---|
1259 | break; |
---|
1260 | continue; |
---|
1261 | } |
---|
1262 | #endif |
---|
1263 | |
---|
1264 | /* |
---|
1265 | * Pipe buffered writes cannot be coincidental with |
---|
1266 | * direct writes. We wait until the currently executing |
---|
1267 | * direct write is completed before we start filling the |
---|
1268 | * pipe buffer. We break out if a signal occurs or the |
---|
1269 | * reader goes away. |
---|
1270 | */ |
---|
1271 | if (wpipe->pipe_state & PIPE_DIRECTW) { |
---|
1272 | if (wpipe->pipe_state & PIPE_WANTR) { |
---|
1273 | wpipe->pipe_state &= ~PIPE_WANTR; |
---|
1274 | wakeup(wpipe); |
---|
1275 | } |
---|
1276 | pipeselwakeup(wpipe); |
---|
1277 | wpipe->pipe_state |= PIPE_WANTW; |
---|
1278 | pipeunlock(wpipe); |
---|
1279 | error = msleep(wpipe, PIPE_MTX(rpipe), PRIBIO | PCATCH, |
---|
1280 | "pipbww", 0); |
---|
1281 | if (error) |
---|
1282 | break; |
---|
1283 | else |
---|
1284 | continue; |
---|
1285 | } |
---|
1286 | |
---|
1287 | space = wpipe->pipe_buffer.size - wpipe->pipe_buffer.cnt; |
---|
1288 | |
---|
1289 | /* Writes of size <= PIPE_BUF must be atomic. */ |
---|
1290 | if ((space < uio->uio_resid) && (orig_resid <= PIPE_BUF)) |
---|
1291 | space = 0; |
---|
1292 | |
---|
1293 | if (space > 0) { |
---|
1294 | int size; /* Transfer size */ |
---|
1295 | int segsize; /* first segment to transfer */ |
---|
1296 | |
---|
1297 | /* |
---|
1298 | * Transfer size is minimum of uio transfer |
---|
1299 | * and free space in pipe buffer. |
---|
1300 | */ |
---|
1301 | if (space > uio->uio_resid) |
---|
1302 | size = uio->uio_resid; |
---|
1303 | else |
---|
1304 | size = space; |
---|
1305 | /* |
---|
1306 | * First segment to transfer is minimum of |
---|
1307 | * transfer size and contiguous space in |
---|
1308 | * pipe buffer. If first segment to transfer |
---|
1309 | * is less than the transfer size, we've got |
---|
1310 | * a wraparound in the buffer. |
---|
1311 | */ |
---|
1312 | segsize = wpipe->pipe_buffer.size - |
---|
1313 | wpipe->pipe_buffer.in; |
---|
1314 | if (segsize > size) |
---|
1315 | segsize = size; |
---|
1316 | |
---|
1317 | /* Transfer first segment */ |
---|
1318 | |
---|
1319 | PIPE_UNLOCK(rpipe); |
---|
1320 | error = uiomove(&wpipe->pipe_buffer.buffer[wpipe->pipe_buffer.in], |
---|
1321 | segsize, uio); |
---|
1322 | PIPE_LOCK(rpipe); |
---|
1323 | |
---|
1324 | if (error == 0 && segsize < size) { |
---|
1325 | KASSERT(wpipe->pipe_buffer.in + segsize == |
---|
1326 | wpipe->pipe_buffer.size, |
---|
1327 | ("Pipe buffer wraparound disappeared")); |
---|
1328 | /* |
---|
1329 | * Transfer remaining part now, to |
---|
1330 | * support atomic writes. Wraparound |
---|
1331 | * happened. |
---|
1332 | */ |
---|
1333 | |
---|
1334 | PIPE_UNLOCK(rpipe); |
---|
1335 | error = uiomove( |
---|
1336 | &wpipe->pipe_buffer.buffer[0], |
---|
1337 | size - segsize, uio); |
---|
1338 | PIPE_LOCK(rpipe); |
---|
1339 | } |
---|
1340 | if (error == 0) { |
---|
1341 | wpipe->pipe_buffer.in += size; |
---|
1342 | if (wpipe->pipe_buffer.in >= |
---|
1343 | wpipe->pipe_buffer.size) { |
---|
1344 | KASSERT(wpipe->pipe_buffer.in == |
---|
1345 | size - segsize + |
---|
1346 | wpipe->pipe_buffer.size, |
---|
1347 | ("Expected wraparound bad")); |
---|
1348 | wpipe->pipe_buffer.in = size - segsize; |
---|
1349 | } |
---|
1350 | |
---|
1351 | wpipe->pipe_buffer.cnt += size; |
---|
1352 | KASSERT(wpipe->pipe_buffer.cnt <= |
---|
1353 | wpipe->pipe_buffer.size, |
---|
1354 | ("Pipe buffer overflow")); |
---|
1355 | } |
---|
1356 | pipeunlock(wpipe); |
---|
1357 | if (error != 0) |
---|
1358 | break; |
---|
1359 | } else { |
---|
1360 | /* |
---|
1361 | * If the "read-side" has been blocked, wake it up now. |
---|
1362 | */ |
---|
1363 | if (wpipe->pipe_state & PIPE_WANTR) { |
---|
1364 | wpipe->pipe_state &= ~PIPE_WANTR; |
---|
1365 | wakeup(wpipe); |
---|
1366 | } |
---|
1367 | |
---|
1368 | /* |
---|
1369 | * don't block on non-blocking I/O |
---|
1370 | */ |
---|
1371 | #ifndef __rtems__ |
---|
1372 | if (fp->f_flag & FNONBLOCK) { |
---|
1373 | #else /* __rtems__ */ |
---|
1374 | if (rtems_bsd_libio_flags_to_fflag(fp->f_io.flags) & FNONBLOCK) { |
---|
1375 | #endif /* __rtems__ */ |
---|
1376 | error = EAGAIN; |
---|
1377 | pipeunlock(wpipe); |
---|
1378 | break; |
---|
1379 | } |
---|
1380 | |
---|
1381 | /* |
---|
1382 | * We have no more space and have something to offer, |
---|
1383 | * wake up select/poll. |
---|
1384 | */ |
---|
1385 | pipeselwakeup(wpipe); |
---|
1386 | |
---|
1387 | wpipe->pipe_state |= PIPE_WANTW; |
---|
1388 | pipeunlock(wpipe); |
---|
1389 | error = msleep(wpipe, PIPE_MTX(rpipe), |
---|
1390 | PRIBIO | PCATCH, "pipewr", 0); |
---|
1391 | if (error != 0) |
---|
1392 | break; |
---|
1393 | } |
---|
1394 | } |
---|
1395 | |
---|
1396 | pipelock(wpipe, 0); |
---|
1397 | --wpipe->pipe_busy; |
---|
1398 | |
---|
1399 | if ((wpipe->pipe_busy == 0) && (wpipe->pipe_state & PIPE_WANT)) { |
---|
1400 | wpipe->pipe_state &= ~(PIPE_WANT | PIPE_WANTR); |
---|
1401 | wakeup(wpipe); |
---|
1402 | } else if (wpipe->pipe_buffer.cnt > 0) { |
---|
1403 | /* |
---|
1404 | * If we have put any characters in the buffer, we wake up |
---|
1405 | * the reader. |
---|
1406 | */ |
---|
1407 | if (wpipe->pipe_state & PIPE_WANTR) { |
---|
1408 | wpipe->pipe_state &= ~PIPE_WANTR; |
---|
1409 | wakeup(wpipe); |
---|
1410 | } |
---|
1411 | } |
---|
1412 | |
---|
1413 | /* |
---|
1414 | * Don't return EPIPE if any byte was written. |
---|
1415 | * EINTR and other interrupts are handled by generic I/O layer. |
---|
1416 | * Do not pretend that I/O succeeded for obvious user error |
---|
1417 | * like EFAULT. |
---|
1418 | */ |
---|
1419 | if (uio->uio_resid != orig_resid && error == EPIPE) |
---|
1420 | error = 0; |
---|
1421 | |
---|
1422 | if (error == 0) |
---|
1423 | #ifndef __rtems__ |
---|
1424 | vfs_timestamp(&wpipe->pipe_mtime); |
---|
1425 | #else /* __rtems__ */ |
---|
1426 | wpipe->pipe_mtime.tv_sec = time(NULL); |
---|
1427 | #endif /* __rtems__ */ |
---|
1428 | |
---|
1429 | /* |
---|
1430 | * We have something to offer, |
---|
1431 | * wake up select/poll. |
---|
1432 | */ |
---|
1433 | if (wpipe->pipe_buffer.cnt) |
---|
1434 | pipeselwakeup(wpipe); |
---|
1435 | |
---|
1436 | pipeunlock(wpipe); |
---|
1437 | PIPE_UNLOCK(rpipe); |
---|
1438 | return (error); |
---|
1439 | } |
---|
1440 | #ifdef __rtems__ |
---|
1441 | static ssize_t |
---|
1442 | rtems_bsd_pipe_write(rtems_libio_t *iop, const void *buffer, size_t count) |
---|
1443 | { |
---|
1444 | struct thread *td = rtems_bsd_get_curthread_or_null(); |
---|
1445 | struct file *fp = rtems_bsd_iop_to_fp(iop); |
---|
1446 | struct iovec iov = { |
---|
1447 | .iov_base = __DECONST(void *, buffer), |
---|
1448 | .iov_len = count |
---|
1449 | }; |
---|
1450 | struct uio auio = { |
---|
1451 | .uio_iov = &iov, |
---|
1452 | .uio_iovcnt = 1, |
---|
1453 | .uio_offset = 0, |
---|
1454 | .uio_resid = count, |
---|
1455 | .uio_segflg = UIO_USERSPACE, |
---|
1456 | .uio_rw = UIO_WRITE, |
---|
1457 | .uio_td = td |
---|
1458 | }; |
---|
1459 | int error; |
---|
1460 | |
---|
1461 | if (td != NULL) { |
---|
1462 | error = pipe_write(fp, &auio, NULL, 0, NULL); |
---|
1463 | } else { |
---|
1464 | error = ENOMEM; |
---|
1465 | } |
---|
1466 | |
---|
1467 | if (error == 0) { |
---|
1468 | return (count - auio.uio_resid); |
---|
1469 | } else { |
---|
1470 | rtems_set_errno_and_return_minus_one(error); |
---|
1471 | } |
---|
1472 | } |
---|
1473 | #endif /* __rtems__ */ |
---|
1474 | |
---|
1475 | /* ARGSUSED */ |
---|
1476 | #ifndef __rtems__ |
---|
1477 | static int |
---|
1478 | pipe_truncate(fp, length, active_cred, td) |
---|
1479 | struct file *fp; |
---|
1480 | off_t length; |
---|
1481 | struct ucred *active_cred; |
---|
1482 | struct thread *td; |
---|
1483 | { |
---|
1484 | struct pipe *cpipe; |
---|
1485 | int error; |
---|
1486 | |
---|
1487 | cpipe = fp->f_data; |
---|
1488 | if (cpipe->pipe_state & PIPE_NAMED) |
---|
1489 | error = vnops.fo_truncate(fp, length, active_cred, td); |
---|
1490 | else |
---|
1491 | error = invfo_truncate(fp, length, active_cred, td); |
---|
1492 | return (error); |
---|
1493 | } |
---|
1494 | #endif /* __rtems__ */ |
---|
1495 | |
---|
1496 | /* |
---|
1497 | * we implement a very minimal set of ioctls for compatibility with sockets. |
---|
1498 | */ |
---|
1499 | static int |
---|
1500 | pipe_ioctl(fp, cmd, data, active_cred, td) |
---|
1501 | struct file *fp; |
---|
1502 | u_long cmd; |
---|
1503 | void *data; |
---|
1504 | struct ucred *active_cred; |
---|
1505 | struct thread *td; |
---|
1506 | { |
---|
1507 | struct pipe *mpipe = fp->f_data; |
---|
1508 | int error; |
---|
1509 | |
---|
1510 | PIPE_LOCK(mpipe); |
---|
1511 | |
---|
1512 | #ifdef MAC |
---|
1513 | error = mac_pipe_check_ioctl(active_cred, mpipe->pipe_pair, cmd, data); |
---|
1514 | if (error) { |
---|
1515 | PIPE_UNLOCK(mpipe); |
---|
1516 | return (error); |
---|
1517 | } |
---|
1518 | #endif |
---|
1519 | |
---|
1520 | error = 0; |
---|
1521 | switch (cmd) { |
---|
1522 | |
---|
1523 | case FIONBIO: |
---|
1524 | break; |
---|
1525 | |
---|
1526 | case FIOASYNC: |
---|
1527 | if (*(int *)data) { |
---|
1528 | mpipe->pipe_state |= PIPE_ASYNC; |
---|
1529 | } else { |
---|
1530 | mpipe->pipe_state &= ~PIPE_ASYNC; |
---|
1531 | } |
---|
1532 | break; |
---|
1533 | |
---|
1534 | case FIONREAD: |
---|
1535 | #ifndef __rtems__ |
---|
1536 | if (!(fp->f_flag & FREAD)) { |
---|
1537 | #else /* __rtems__ */ |
---|
1538 | if (!(rtems_bsd_libio_flags_to_fflag(fp->f_io.flags) & FREAD)) { |
---|
1539 | #endif /* __rtems__ */ |
---|
1540 | *(int *)data = 0; |
---|
1541 | PIPE_UNLOCK(mpipe); |
---|
1542 | return (0); |
---|
1543 | } |
---|
1544 | if (mpipe->pipe_state & PIPE_DIRECTW) |
---|
1545 | *(int *)data = mpipe->pipe_map.cnt; |
---|
1546 | else |
---|
1547 | *(int *)data = mpipe->pipe_buffer.cnt; |
---|
1548 | break; |
---|
1549 | |
---|
1550 | case FIOSETOWN: |
---|
1551 | PIPE_UNLOCK(mpipe); |
---|
1552 | error = fsetown(*(int *)data, &mpipe->pipe_sigio); |
---|
1553 | goto out_unlocked; |
---|
1554 | |
---|
1555 | case FIOGETOWN: |
---|
1556 | *(int *)data = fgetown(&mpipe->pipe_sigio); |
---|
1557 | break; |
---|
1558 | |
---|
1559 | /* This is deprecated, FIOSETOWN should be used instead. */ |
---|
1560 | case TIOCSPGRP: |
---|
1561 | PIPE_UNLOCK(mpipe); |
---|
1562 | error = fsetown(-(*(int *)data), &mpipe->pipe_sigio); |
---|
1563 | goto out_unlocked; |
---|
1564 | |
---|
1565 | /* This is deprecated, FIOGETOWN should be used instead. */ |
---|
1566 | case TIOCGPGRP: |
---|
1567 | *(int *)data = -fgetown(&mpipe->pipe_sigio); |
---|
1568 | break; |
---|
1569 | |
---|
1570 | default: |
---|
1571 | error = ENOTTY; |
---|
1572 | break; |
---|
1573 | } |
---|
1574 | PIPE_UNLOCK(mpipe); |
---|
1575 | out_unlocked: |
---|
1576 | return (error); |
---|
1577 | } |
---|
1578 | #ifdef __rtems__ |
---|
1579 | static int |
---|
1580 | rtems_bsd_pipe_ioctl(rtems_libio_t *iop, ioctl_command_t request, void *buffer) |
---|
1581 | { |
---|
1582 | struct thread *td = rtems_bsd_get_curthread_or_null(); |
---|
1583 | struct file *fp = rtems_bsd_iop_to_fp(iop); |
---|
1584 | int error; |
---|
1585 | |
---|
1586 | if (td != NULL) { |
---|
1587 | error = pipe_ioctl(fp, request, buffer, NULL, td); |
---|
1588 | } else { |
---|
1589 | error = ENOMEM; |
---|
1590 | } |
---|
1591 | |
---|
1592 | return rtems_bsd_error_to_status_and_errno(error); |
---|
1593 | } |
---|
1594 | #endif /* __rtems__ */ |
---|
1595 | |
---|
1596 | static int |
---|
1597 | pipe_poll(fp, events, active_cred, td) |
---|
1598 | struct file *fp; |
---|
1599 | int events; |
---|
1600 | struct ucred *active_cred; |
---|
1601 | struct thread *td; |
---|
1602 | { |
---|
1603 | struct pipe *rpipe; |
---|
1604 | struct pipe *wpipe; |
---|
1605 | int levents, revents; |
---|
1606 | #ifdef MAC |
---|
1607 | int error; |
---|
1608 | #endif |
---|
1609 | |
---|
1610 | revents = 0; |
---|
1611 | rpipe = fp->f_data; |
---|
1612 | wpipe = PIPE_PEER(rpipe); |
---|
1613 | PIPE_LOCK(rpipe); |
---|
1614 | #ifdef MAC |
---|
1615 | error = mac_pipe_check_poll(active_cred, rpipe->pipe_pair); |
---|
1616 | if (error) |
---|
1617 | goto locked_error; |
---|
1618 | #endif |
---|
1619 | #ifndef __rtems__ |
---|
1620 | if (fp->f_flag & FREAD && events & (POLLIN | POLLRDNORM)) |
---|
1621 | #else /* __rtems__ */ |
---|
1622 | if (rtems_bsd_libio_flags_to_fflag(fp->f_io.flags) & FREAD && events & (POLLIN | POLLRDNORM)) |
---|
1623 | #endif /* __rtems__ */ |
---|
1624 | if ((rpipe->pipe_state & PIPE_DIRECTW) || |
---|
1625 | (rpipe->pipe_buffer.cnt > 0)) |
---|
1626 | revents |= events & (POLLIN | POLLRDNORM); |
---|
1627 | |
---|
1628 | #ifndef __rtems__ |
---|
1629 | if (fp->f_flag & FWRITE && events & (POLLOUT | POLLWRNORM)) |
---|
1630 | #else /* __rtems__ */ |
---|
1631 | if (rtems_bsd_libio_flags_to_fflag(fp->f_io.flags) & FWRITE && events & (POLLOUT | POLLWRNORM)) |
---|
1632 | #endif /* __rtems__ */ |
---|
1633 | if (wpipe->pipe_present != PIPE_ACTIVE || |
---|
1634 | (wpipe->pipe_state & PIPE_EOF) || |
---|
1635 | (((wpipe->pipe_state & PIPE_DIRECTW) == 0) && |
---|
1636 | ((wpipe->pipe_buffer.size - wpipe->pipe_buffer.cnt) >= PIPE_BUF || |
---|
1637 | wpipe->pipe_buffer.size == 0))) |
---|
1638 | revents |= events & (POLLOUT | POLLWRNORM); |
---|
1639 | |
---|
1640 | levents = events & |
---|
1641 | (POLLIN | POLLINIGNEOF | POLLPRI | POLLRDNORM | POLLRDBAND); |
---|
1642 | #ifndef __rtems__ |
---|
1643 | if (rpipe->pipe_state & PIPE_NAMED && fp->f_flag & FREAD && levents && |
---|
1644 | fp->f_seqcount == rpipe->pipe_wgen) |
---|
1645 | #else /* __rtems__ */ |
---|
1646 | if (rpipe->pipe_state & PIPE_NAMED && rtems_bsd_libio_flags_to_fflag(fp->f_io.flags) & FREAD && levents) |
---|
1647 | #endif /* __rtems__ */ |
---|
1648 | events |= POLLINIGNEOF; |
---|
1649 | |
---|
1650 | if ((events & POLLINIGNEOF) == 0) { |
---|
1651 | if (rpipe->pipe_state & PIPE_EOF) { |
---|
1652 | revents |= (events & (POLLIN | POLLRDNORM)); |
---|
1653 | if (wpipe->pipe_present != PIPE_ACTIVE || |
---|
1654 | (wpipe->pipe_state & PIPE_EOF)) |
---|
1655 | revents |= POLLHUP; |
---|
1656 | } |
---|
1657 | } |
---|
1658 | |
---|
1659 | if (revents == 0) { |
---|
1660 | #ifndef __rtems__ |
---|
1661 | if (fp->f_flag & FREAD && events & (POLLIN | POLLRDNORM)) { |
---|
1662 | #else /* __rtems__ */ |
---|
1663 | if (rtems_bsd_libio_flags_to_fflag(fp->f_io.flags) & FREAD && events & (POLLIN | POLLRDNORM)) { |
---|
1664 | #endif /* __rtems__ */ |
---|
1665 | selrecord(td, &rpipe->pipe_sel); |
---|
1666 | if (SEL_WAITING(&rpipe->pipe_sel)) |
---|
1667 | rpipe->pipe_state |= PIPE_SEL; |
---|
1668 | } |
---|
1669 | |
---|
1670 | #ifndef __rtems__ |
---|
1671 | if (fp->f_flag & FWRITE && events & (POLLOUT | POLLWRNORM)) { |
---|
1672 | #else /* __rtems__ */ |
---|
1673 | if (rtems_bsd_libio_flags_to_fflag(fp->f_io.flags) & FWRITE && events & (POLLOUT | POLLWRNORM)) { |
---|
1674 | #endif /* __rtems__ */ |
---|
1675 | selrecord(td, &wpipe->pipe_sel); |
---|
1676 | if (SEL_WAITING(&wpipe->pipe_sel)) |
---|
1677 | wpipe->pipe_state |= PIPE_SEL; |
---|
1678 | } |
---|
1679 | } |
---|
1680 | #ifdef MAC |
---|
1681 | locked_error: |
---|
1682 | #endif |
---|
1683 | PIPE_UNLOCK(rpipe); |
---|
1684 | |
---|
1685 | return (revents); |
---|
1686 | } |
---|
1687 | #ifdef __rtems__ |
---|
1688 | static int |
---|
1689 | rtems_bsd_pipe_poll(rtems_libio_t *iop, int events) |
---|
1690 | { |
---|
1691 | struct thread *td = rtems_bsd_get_curthread_or_null(); |
---|
1692 | struct file *fp = rtems_bsd_iop_to_fp(iop); |
---|
1693 | int error; |
---|
1694 | |
---|
1695 | if (td != NULL) { |
---|
1696 | error = pipe_poll(fp, events, NULL, td); |
---|
1697 | } else { |
---|
1698 | error = ENOMEM; |
---|
1699 | } |
---|
1700 | |
---|
1701 | return error; |
---|
1702 | } |
---|
1703 | #endif /* __rtems__ */ |
---|
1704 | |
---|
1705 | /* |
---|
1706 | * We shouldn't need locks here as we're doing a read and this should |
---|
1707 | * be a natural race. |
---|
1708 | */ |
---|
1709 | #ifndef __rtems__ |
---|
1710 | static int |
---|
1711 | pipe_stat(fp, ub, active_cred, td) |
---|
1712 | struct file *fp; |
---|
1713 | struct stat *ub; |
---|
1714 | struct ucred *active_cred; |
---|
1715 | struct thread *td; |
---|
1716 | { |
---|
1717 | struct pipe *pipe; |
---|
1718 | #else /* __rtems__ */ |
---|
1719 | static int |
---|
1720 | pipe_stat(struct pipe *pipe, struct stat *ub) |
---|
1721 | { |
---|
1722 | #endif /* __rtems__ */ |
---|
1723 | int new_unr; |
---|
1724 | #ifdef MAC |
---|
1725 | int error; |
---|
1726 | #endif |
---|
1727 | |
---|
1728 | #ifndef __rtems__ |
---|
1729 | pipe = fp->f_data; |
---|
1730 | #endif /* __rtems__ */ |
---|
1731 | PIPE_LOCK(pipe); |
---|
1732 | #ifdef MAC |
---|
1733 | error = mac_pipe_check_stat(active_cred, pipe->pipe_pair); |
---|
1734 | if (error) { |
---|
1735 | PIPE_UNLOCK(pipe); |
---|
1736 | return (error); |
---|
1737 | } |
---|
1738 | #endif |
---|
1739 | |
---|
1740 | /* For named pipes ask the underlying filesystem. */ |
---|
1741 | if (pipe->pipe_state & PIPE_NAMED) { |
---|
1742 | PIPE_UNLOCK(pipe); |
---|
1743 | #ifndef __rtems__ |
---|
1744 | return (vnops.fo_stat(fp, ub, active_cred, td)); |
---|
1745 | #else /* __rtems__ */ |
---|
1746 | return (ENXIO); |
---|
1747 | #endif /* __rtems__ */ |
---|
1748 | } |
---|
1749 | |
---|
1750 | /* |
---|
1751 | * Lazily allocate an inode number for the pipe. Most pipe |
---|
1752 | * users do not call fstat(2) on the pipe, which means that |
---|
1753 | * postponing the inode allocation until it is must be |
---|
1754 | * returned to userland is useful. If alloc_unr failed, |
---|
1755 | * assign st_ino zero instead of returning an error. |
---|
1756 | * Special pipe_ino values: |
---|
1757 | * -1 - not yet initialized; |
---|
1758 | * 0 - alloc_unr failed, return 0 as st_ino forever. |
---|
1759 | */ |
---|
1760 | if (pipe->pipe_ino == (ino_t)-1) { |
---|
1761 | new_unr = alloc_unr(pipeino_unr); |
---|
1762 | if (new_unr != -1) |
---|
1763 | pipe->pipe_ino = new_unr; |
---|
1764 | else |
---|
1765 | pipe->pipe_ino = 0; |
---|
1766 | } |
---|
1767 | PIPE_UNLOCK(pipe); |
---|
1768 | |
---|
1769 | #ifndef __rtems__ |
---|
1770 | bzero(ub, sizeof(*ub)); |
---|
1771 | #endif /* __rtems__ */ |
---|
1772 | ub->st_mode = S_IFIFO; |
---|
1773 | ub->st_blksize = PAGE_SIZE; |
---|
1774 | if (pipe->pipe_state & PIPE_DIRECTW) |
---|
1775 | ub->st_size = pipe->pipe_map.cnt; |
---|
1776 | else |
---|
1777 | ub->st_size = pipe->pipe_buffer.cnt; |
---|
1778 | ub->st_blocks = howmany(ub->st_size, ub->st_blksize); |
---|
1779 | ub->st_atim = pipe->pipe_atime; |
---|
1780 | ub->st_mtim = pipe->pipe_mtime; |
---|
1781 | ub->st_ctim = pipe->pipe_ctime; |
---|
1782 | #ifndef __rtems__ |
---|
1783 | ub->st_uid = fp->f_cred->cr_uid; |
---|
1784 | ub->st_gid = fp->f_cred->cr_gid; |
---|
1785 | ub->st_dev = pipedev_ino; |
---|
1786 | ub->st_ino = pipe->pipe_ino; |
---|
1787 | #else /* __rtems__ */ |
---|
1788 | ub->st_uid = BSD_DEFAULT_UID; |
---|
1789 | ub->st_gid = BSD_DEFAULT_GID; |
---|
1790 | ub->st_dev = rtems_filesystem_make_dev_t(0xcc494cd6U, 0x1d970b4dU); |
---|
1791 | ub->st_ino = pipe->pipe_ino; |
---|
1792 | #endif /* __rtems__ */ |
---|
1793 | /* |
---|
1794 | * Left as 0: st_nlink, st_rdev, st_flags, st_gen. |
---|
1795 | */ |
---|
1796 | return (0); |
---|
1797 | } |
---|
1798 | #ifdef __rtems__ |
---|
1799 | static int |
---|
1800 | rtems_bsd_pipe_stat( |
---|
1801 | const rtems_filesystem_location_info_t *loc, |
---|
1802 | struct stat *buf |
---|
1803 | ) |
---|
1804 | { |
---|
1805 | struct pipe *pipe = rtems_bsd_loc_to_f_data(loc); |
---|
1806 | int error = pipe_stat(pipe, buf); |
---|
1807 | |
---|
1808 | return rtems_bsd_error_to_status_and_errno(error); |
---|
1809 | } |
---|
1810 | #endif /* __rtems__ */ |
---|
1811 | |
---|
1812 | /* ARGSUSED */ |
---|
1813 | static int |
---|
1814 | pipe_close(fp, td) |
---|
1815 | struct file *fp; |
---|
1816 | struct thread *td; |
---|
1817 | { |
---|
1818 | |
---|
1819 | #ifndef __rtems__ |
---|
1820 | if (fp->f_vnode != NULL) |
---|
1821 | return vnops.fo_close(fp, td); |
---|
1822 | fp->f_ops = &badfileops; |
---|
1823 | #else /* __rtems__ */ |
---|
1824 | fp->f_io.pathinfo.handlers = &rtems_filesystem_handlers_default; |
---|
1825 | #endif /* __rtems__ */ |
---|
1826 | pipe_dtor(fp->f_data); |
---|
1827 | fp->f_data = NULL; |
---|
1828 | return (0); |
---|
1829 | } |
---|
1830 | |
---|
1831 | #ifndef __rtems__ |
---|
1832 | static int |
---|
1833 | pipe_chmod(struct file *fp, mode_t mode, struct ucred *active_cred, struct thread *td) |
---|
1834 | { |
---|
1835 | struct pipe *cpipe; |
---|
1836 | int error; |
---|
1837 | |
---|
1838 | cpipe = fp->f_data; |
---|
1839 | if (cpipe->pipe_state & PIPE_NAMED) |
---|
1840 | error = vn_chmod(fp, mode, active_cred, td); |
---|
1841 | else |
---|
1842 | error = invfo_chmod(fp, mode, active_cred, td); |
---|
1843 | return (error); |
---|
1844 | } |
---|
1845 | |
---|
1846 | static int |
---|
1847 | pipe_chown(fp, uid, gid, active_cred, td) |
---|
1848 | struct file *fp; |
---|
1849 | uid_t uid; |
---|
1850 | gid_t gid; |
---|
1851 | struct ucred *active_cred; |
---|
1852 | struct thread *td; |
---|
1853 | { |
---|
1854 | struct pipe *cpipe; |
---|
1855 | int error; |
---|
1856 | |
---|
1857 | cpipe = fp->f_data; |
---|
1858 | if (cpipe->pipe_state & PIPE_NAMED) |
---|
1859 | error = vn_chown(fp, uid, gid, active_cred, td); |
---|
1860 | else |
---|
1861 | error = invfo_chown(fp, uid, gid, active_cred, td); |
---|
1862 | return (error); |
---|
1863 | } |
---|
1864 | |
---|
1865 | static int |
---|
1866 | pipe_fill_kinfo(struct file *fp, struct kinfo_file *kif, struct filedesc *fdp) |
---|
1867 | { |
---|
1868 | struct pipe *pi; |
---|
1869 | |
---|
1870 | if (fp->f_type == DTYPE_FIFO) |
---|
1871 | return (vn_fill_kinfo(fp, kif, fdp)); |
---|
1872 | kif->kf_type = KF_TYPE_PIPE; |
---|
1873 | pi = fp->f_data; |
---|
1874 | kif->kf_un.kf_pipe.kf_pipe_addr = (uintptr_t)pi; |
---|
1875 | kif->kf_un.kf_pipe.kf_pipe_peer = (uintptr_t)pi->pipe_peer; |
---|
1876 | kif->kf_un.kf_pipe.kf_pipe_buffer_cnt = pi->pipe_buffer.cnt; |
---|
1877 | return (0); |
---|
1878 | } |
---|
1879 | #endif /* __rtems__ */ |
---|
1880 | |
---|
1881 | static void |
---|
1882 | pipe_free_kmem(cpipe) |
---|
1883 | struct pipe *cpipe; |
---|
1884 | { |
---|
1885 | |
---|
1886 | KASSERT(!mtx_owned(PIPE_MTX(cpipe)), |
---|
1887 | ("pipe_free_kmem: pipe mutex locked")); |
---|
1888 | |
---|
1889 | if (cpipe->pipe_buffer.buffer != NULL) { |
---|
1890 | atomic_subtract_long(&amountpipekva, cpipe->pipe_buffer.size); |
---|
1891 | #ifndef __rtems__ |
---|
1892 | vm_map_remove(pipe_map, |
---|
1893 | (vm_offset_t)cpipe->pipe_buffer.buffer, |
---|
1894 | (vm_offset_t)cpipe->pipe_buffer.buffer + cpipe->pipe_buffer.size); |
---|
1895 | #else /* __rtems__ */ |
---|
1896 | free(cpipe->pipe_buffer.buffer, M_TEMP); |
---|
1897 | #endif /* __rtems__ */ |
---|
1898 | cpipe->pipe_buffer.buffer = NULL; |
---|
1899 | } |
---|
1900 | #ifndef PIPE_NODIRECT |
---|
1901 | { |
---|
1902 | cpipe->pipe_map.cnt = 0; |
---|
1903 | cpipe->pipe_map.pos = 0; |
---|
1904 | cpipe->pipe_map.npages = 0; |
---|
1905 | } |
---|
1906 | #endif |
---|
1907 | } |
---|
1908 | |
---|
1909 | /* |
---|
1910 | * shutdown the pipe |
---|
1911 | */ |
---|
1912 | static void |
---|
1913 | pipeclose(cpipe) |
---|
1914 | struct pipe *cpipe; |
---|
1915 | { |
---|
1916 | struct pipepair *pp; |
---|
1917 | struct pipe *ppipe; |
---|
1918 | |
---|
1919 | KASSERT(cpipe != NULL, ("pipeclose: cpipe == NULL")); |
---|
1920 | |
---|
1921 | PIPE_LOCK(cpipe); |
---|
1922 | pipelock(cpipe, 0); |
---|
1923 | pp = cpipe->pipe_pair; |
---|
1924 | |
---|
1925 | pipeselwakeup(cpipe); |
---|
1926 | |
---|
1927 | /* |
---|
1928 | * If the other side is blocked, wake it up saying that |
---|
1929 | * we want to close it down. |
---|
1930 | */ |
---|
1931 | cpipe->pipe_state |= PIPE_EOF; |
---|
1932 | while (cpipe->pipe_busy) { |
---|
1933 | wakeup(cpipe); |
---|
1934 | cpipe->pipe_state |= PIPE_WANT; |
---|
1935 | pipeunlock(cpipe); |
---|
1936 | msleep(cpipe, PIPE_MTX(cpipe), PRIBIO, "pipecl", 0); |
---|
1937 | pipelock(cpipe, 0); |
---|
1938 | } |
---|
1939 | |
---|
1940 | |
---|
1941 | /* |
---|
1942 | * Disconnect from peer, if any. |
---|
1943 | */ |
---|
1944 | ppipe = cpipe->pipe_peer; |
---|
1945 | if (ppipe->pipe_present == PIPE_ACTIVE) { |
---|
1946 | pipeselwakeup(ppipe); |
---|
1947 | |
---|
1948 | ppipe->pipe_state |= PIPE_EOF; |
---|
1949 | wakeup(ppipe); |
---|
1950 | KNOTE_LOCKED(&ppipe->pipe_sel.si_note, 0); |
---|
1951 | } |
---|
1952 | |
---|
1953 | /* |
---|
1954 | * Mark this endpoint as free. Release kmem resources. We |
---|
1955 | * don't mark this endpoint as unused until we've finished |
---|
1956 | * doing that, or the pipe might disappear out from under |
---|
1957 | * us. |
---|
1958 | */ |
---|
1959 | PIPE_UNLOCK(cpipe); |
---|
1960 | pipe_free_kmem(cpipe); |
---|
1961 | PIPE_LOCK(cpipe); |
---|
1962 | cpipe->pipe_present = PIPE_CLOSING; |
---|
1963 | pipeunlock(cpipe); |
---|
1964 | |
---|
1965 | /* |
---|
1966 | * knlist_clear() may sleep dropping the PIPE_MTX. Set the |
---|
1967 | * PIPE_FINALIZED, that allows other end to free the |
---|
1968 | * pipe_pair, only after the knotes are completely dismantled. |
---|
1969 | */ |
---|
1970 | knlist_clear(&cpipe->pipe_sel.si_note, 1); |
---|
1971 | cpipe->pipe_present = PIPE_FINALIZED; |
---|
1972 | seldrain(&cpipe->pipe_sel); |
---|
1973 | knlist_destroy(&cpipe->pipe_sel.si_note); |
---|
1974 | |
---|
1975 | /* |
---|
1976 | * If both endpoints are now closed, release the memory for the |
---|
1977 | * pipe pair. If not, unlock. |
---|
1978 | */ |
---|
1979 | if (ppipe->pipe_present == PIPE_FINALIZED) { |
---|
1980 | PIPE_UNLOCK(cpipe); |
---|
1981 | #ifdef MAC |
---|
1982 | mac_pipe_destroy(pp); |
---|
1983 | #endif |
---|
1984 | uma_zfree(pipe_zone, cpipe->pipe_pair); |
---|
1985 | } else |
---|
1986 | PIPE_UNLOCK(cpipe); |
---|
1987 | } |
---|
1988 | |
---|
1989 | /*ARGSUSED*/ |
---|
1990 | static int |
---|
1991 | pipe_kqfilter(struct file *fp, struct knote *kn) |
---|
1992 | { |
---|
1993 | struct pipe *cpipe; |
---|
1994 | |
---|
1995 | /* |
---|
1996 | * If a filter is requested that is not supported by this file |
---|
1997 | * descriptor, don't return an error, but also don't ever generate an |
---|
1998 | * event. |
---|
1999 | */ |
---|
2000 | #ifndef __rtems__ |
---|
2001 | if ((kn->kn_filter == EVFILT_READ) && !(fp->f_flag & FREAD)) { |
---|
2002 | #else /* __rtems__ */ |
---|
2003 | if ((kn->kn_filter == EVFILT_READ) && !(rtems_bsd_libio_flags_to_fflag(fp->f_io.flags) & FREAD)) { |
---|
2004 | #endif /* __rtems__ */ |
---|
2005 | kn->kn_fop = &pipe_nfiltops; |
---|
2006 | return (0); |
---|
2007 | } |
---|
2008 | #ifndef __rtems__ |
---|
2009 | if ((kn->kn_filter == EVFILT_WRITE) && !(fp->f_flag & FWRITE)) { |
---|
2010 | #else /* __rtems__ */ |
---|
2011 | if ((kn->kn_filter == EVFILT_WRITE) && !(rtems_bsd_libio_flags_to_fflag(fp->f_io.flags) & FWRITE)) { |
---|
2012 | #endif /* __rtems__ */ |
---|
2013 | kn->kn_fop = &pipe_nfiltops; |
---|
2014 | return (0); |
---|
2015 | } |
---|
2016 | cpipe = fp->f_data; |
---|
2017 | PIPE_LOCK(cpipe); |
---|
2018 | switch (kn->kn_filter) { |
---|
2019 | case EVFILT_READ: |
---|
2020 | kn->kn_fop = &pipe_rfiltops; |
---|
2021 | break; |
---|
2022 | case EVFILT_WRITE: |
---|
2023 | kn->kn_fop = &pipe_wfiltops; |
---|
2024 | if (cpipe->pipe_peer->pipe_present != PIPE_ACTIVE) { |
---|
2025 | /* other end of pipe has been closed */ |
---|
2026 | PIPE_UNLOCK(cpipe); |
---|
2027 | return (EPIPE); |
---|
2028 | } |
---|
2029 | cpipe = PIPE_PEER(cpipe); |
---|
2030 | break; |
---|
2031 | default: |
---|
2032 | PIPE_UNLOCK(cpipe); |
---|
2033 | return (EINVAL); |
---|
2034 | } |
---|
2035 | |
---|
2036 | kn->kn_hook = cpipe; |
---|
2037 | knlist_add(&cpipe->pipe_sel.si_note, kn, 1); |
---|
2038 | PIPE_UNLOCK(cpipe); |
---|
2039 | return (0); |
---|
2040 | } |
---|
2041 | #ifdef __rtems__ |
---|
2042 | int |
---|
2043 | rtems_bsd_pipe_kqfilter(rtems_libio_t *iop, struct knote *kn) |
---|
2044 | { |
---|
2045 | struct file *fp = rtems_bsd_iop_to_fp(iop); |
---|
2046 | |
---|
2047 | return pipe_kqfilter(fp, kn); |
---|
2048 | } |
---|
2049 | #endif /* __rtems__ */ |
---|
2050 | |
---|
2051 | static void |
---|
2052 | filt_pipedetach(struct knote *kn) |
---|
2053 | { |
---|
2054 | struct pipe *cpipe = kn->kn_hook; |
---|
2055 | |
---|
2056 | PIPE_LOCK(cpipe); |
---|
2057 | knlist_remove(&cpipe->pipe_sel.si_note, kn, 1); |
---|
2058 | PIPE_UNLOCK(cpipe); |
---|
2059 | } |
---|
2060 | |
---|
2061 | /*ARGSUSED*/ |
---|
2062 | static int |
---|
2063 | filt_piperead(struct knote *kn, long hint) |
---|
2064 | { |
---|
2065 | struct pipe *rpipe = kn->kn_hook; |
---|
2066 | struct pipe *wpipe = rpipe->pipe_peer; |
---|
2067 | int ret; |
---|
2068 | |
---|
2069 | PIPE_LOCK_ASSERT(rpipe, MA_OWNED); |
---|
2070 | kn->kn_data = rpipe->pipe_buffer.cnt; |
---|
2071 | if ((kn->kn_data == 0) && (rpipe->pipe_state & PIPE_DIRECTW)) |
---|
2072 | kn->kn_data = rpipe->pipe_map.cnt; |
---|
2073 | |
---|
2074 | if ((rpipe->pipe_state & PIPE_EOF) || |
---|
2075 | wpipe->pipe_present != PIPE_ACTIVE || |
---|
2076 | (wpipe->pipe_state & PIPE_EOF)) { |
---|
2077 | kn->kn_flags |= EV_EOF; |
---|
2078 | return (1); |
---|
2079 | } |
---|
2080 | ret = kn->kn_data > 0; |
---|
2081 | return ret; |
---|
2082 | } |
---|
2083 | |
---|
2084 | /*ARGSUSED*/ |
---|
2085 | static int |
---|
2086 | filt_pipewrite(struct knote *kn, long hint) |
---|
2087 | { |
---|
2088 | struct pipe *wpipe; |
---|
2089 | |
---|
2090 | wpipe = kn->kn_hook; |
---|
2091 | PIPE_LOCK_ASSERT(wpipe, MA_OWNED); |
---|
2092 | if (wpipe->pipe_present != PIPE_ACTIVE || |
---|
2093 | (wpipe->pipe_state & PIPE_EOF)) { |
---|
2094 | kn->kn_data = 0; |
---|
2095 | kn->kn_flags |= EV_EOF; |
---|
2096 | return (1); |
---|
2097 | } |
---|
2098 | kn->kn_data = (wpipe->pipe_buffer.size > 0) ? |
---|
2099 | (wpipe->pipe_buffer.size - wpipe->pipe_buffer.cnt) : PIPE_BUF; |
---|
2100 | if (wpipe->pipe_state & PIPE_DIRECTW) |
---|
2101 | kn->kn_data = 0; |
---|
2102 | |
---|
2103 | return (kn->kn_data >= PIPE_BUF); |
---|
2104 | } |
---|
2105 | |
---|
2106 | static void |
---|
2107 | filt_pipedetach_notsup(struct knote *kn) |
---|
2108 | { |
---|
2109 | |
---|
2110 | } |
---|
2111 | |
---|
2112 | static int |
---|
2113 | filt_pipenotsup(struct knote *kn, long hint) |
---|
2114 | { |
---|
2115 | |
---|
2116 | return (0); |
---|
2117 | } |
---|
2118 | #ifdef __rtems__ |
---|
2119 | static int |
---|
2120 | rtems_bsd_pipe_open(rtems_libio_t *iop, const char *path, int oflag, |
---|
2121 | mode_t mode) |
---|
2122 | { |
---|
2123 | return rtems_bsd_error_to_status_and_errno(ENXIO); |
---|
2124 | } |
---|
2125 | |
---|
2126 | static int |
---|
2127 | rtems_bsd_pipe_close(rtems_libio_t *iop) |
---|
2128 | { |
---|
2129 | struct file *fp = rtems_bsd_iop_to_fp(iop); |
---|
2130 | int error = pipe_close(fp, NULL); |
---|
2131 | |
---|
2132 | return rtems_bsd_error_to_status_and_errno(error); |
---|
2133 | } |
---|
2134 | |
---|
2135 | static int |
---|
2136 | rtems_bsd_pipe_fcntl(rtems_libio_t *iop, int cmd) |
---|
2137 | { |
---|
2138 | int error = 0; |
---|
2139 | |
---|
2140 | if (cmd == F_SETFL) { |
---|
2141 | struct file *fp = rtems_bsd_iop_to_fp(iop); |
---|
2142 | int nbio = iop->flags & LIBIO_FLAGS_NO_DELAY; |
---|
2143 | |
---|
2144 | error = pipe_ioctl(fp, FIONBIO, &nbio, NULL, NULL); |
---|
2145 | } |
---|
2146 | |
---|
2147 | return rtems_bsd_error_to_status_and_errno(error); |
---|
2148 | } |
---|
2149 | #endif /* __rtems__ */ |
---|