1 | /* |
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2 | **************************************************************************** |
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3 | * (C) 2006 - Cambridge University |
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4 | **************************************************************************** |
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5 | * |
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6 | * File: xenbus.c |
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7 | * Author: Steven Smith (sos22@cam.ac.uk) |
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8 | * Changes: Grzegorz Milos (gm281@cam.ac.uk) |
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9 | * Changes: John D. Ramsdell |
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10 | * |
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11 | * Date: Jun 2006, chages Aug 2005 |
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12 | * |
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13 | * Environment: Xen Minimal OS |
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14 | * Description: Minimal implementation of xenbus |
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15 | * |
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16 | **************************************************************************** |
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17 | **/ |
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18 | #include <os.h> |
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19 | #include <mm.h> |
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20 | #include <traps.h> |
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21 | #include <lib.h> |
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22 | #include <xenbus.h> |
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23 | #include <events.h> |
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24 | #include <errno.h> |
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25 | #include <sched.h> |
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26 | #include <wait.h> |
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27 | #include <xen/io/xs_wire.h> |
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28 | #include <spinlock.h> |
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29 | #include <xmalloc.h> |
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30 | |
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31 | #define BUG_ON(x) do { \ |
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32 | if (x) {printk("BUG at %s:%d\n", __FILE__, __LINE__); BUG(); } \ |
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33 | } while (0) |
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34 | |
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35 | #define min(x,y) ({ \ |
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36 | typeof(x) tmpx = (x); \ |
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37 | typeof(y) tmpy = (y); \ |
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38 | tmpx < tmpy ? tmpx : tmpy; \ |
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39 | }) |
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40 | |
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41 | #ifdef XENBUS_DEBUG |
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42 | #define DEBUG(_f, _a...) \ |
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43 | printk("MINI_OS(file=xenbus.c, line=%d) " _f , __LINE__, ## _a) |
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44 | #else |
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45 | #define DEBUG(_f, _a...) ((void)0) |
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46 | #endif |
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47 | |
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48 | static struct xenstore_domain_interface *xenstore_buf; |
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49 | static DECLARE_WAIT_QUEUE_HEAD(xb_waitq); |
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50 | static DECLARE_WAIT_QUEUE_HEAD(watch_queue); |
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51 | struct xenbus_req_info |
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52 | { |
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53 | int in_use:1; |
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54 | struct wait_queue_head waitq; |
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55 | void *reply; |
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56 | }; |
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57 | |
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58 | #define NR_REQS 32 |
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59 | static struct xenbus_req_info req_info[NR_REQS]; |
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60 | |
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61 | static void memcpy_from_ring(const void *Ring, |
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62 | void *Dest, |
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63 | int off, |
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64 | int len) |
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65 | { |
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66 | int c1, c2; |
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67 | const char *ring = Ring; |
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68 | char *dest = Dest; |
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69 | c1 = min(len, XENSTORE_RING_SIZE - off); |
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70 | c2 = len - c1; |
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71 | memcpy(dest, ring + off, c1); |
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72 | memcpy(dest + c1, ring, c2); |
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73 | } |
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74 | |
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75 | void wait_for_watch(void) |
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76 | { |
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77 | DEFINE_WAIT(w); |
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78 | add_waiter(w,watch_queue); |
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79 | schedule(); |
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80 | remove_waiter(w); |
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81 | wake(current); |
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82 | } |
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83 | |
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84 | char* xenbus_wait_for_value(const char* path,const char* value) |
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85 | { |
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86 | for(;;) |
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87 | { |
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88 | char *res, *msg; |
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89 | int r; |
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90 | |
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91 | msg = xenbus_read(XBT_NIL, path, &res); |
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92 | if(msg) return msg; |
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93 | |
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94 | r = strcmp(value,res); |
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95 | free(res); |
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96 | |
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97 | if(r==0) break; |
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98 | else wait_for_watch(); |
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99 | } |
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100 | return NULL; |
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101 | } |
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102 | |
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103 | |
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104 | static void xenbus_thread_func(void *ign) |
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105 | { |
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106 | struct xsd_sockmsg msg; |
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107 | unsigned prod = 0; |
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108 | |
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109 | for (;;) |
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110 | { |
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111 | wait_event(xb_waitq, prod != xenstore_buf->rsp_prod); |
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112 | while (1) |
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113 | { |
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114 | prod = xenstore_buf->rsp_prod; |
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115 | DEBUG("Rsp_cons %d, rsp_prod %d.\n", xenstore_buf->rsp_cons, |
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116 | xenstore_buf->rsp_prod); |
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117 | if (xenstore_buf->rsp_prod - xenstore_buf->rsp_cons < sizeof(msg)) |
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118 | break; |
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119 | rmb(); |
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120 | memcpy_from_ring(xenstore_buf->rsp, |
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121 | &msg, |
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122 | MASK_XENSTORE_IDX(xenstore_buf->rsp_cons), |
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123 | sizeof(msg)); |
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124 | DEBUG("Msg len %d, %d avail, id %d.\n", |
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125 | msg.len + sizeof(msg), |
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126 | xenstore_buf->rsp_prod - xenstore_buf->rsp_cons, |
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127 | msg.req_id); |
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128 | if (xenstore_buf->rsp_prod - xenstore_buf->rsp_cons < |
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129 | sizeof(msg) + msg.len) |
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130 | break; |
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131 | |
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132 | DEBUG("Message is good.\n"); |
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133 | |
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134 | if(msg.type == XS_WATCH_EVENT) |
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135 | { |
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136 | char* payload = (char*)malloc(sizeof(msg) + msg.len); |
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137 | char *path,*token; |
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138 | |
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139 | memcpy_from_ring(xenstore_buf->rsp, |
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140 | payload, |
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141 | MASK_XENSTORE_IDX(xenstore_buf->rsp_cons), |
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142 | msg.len + sizeof(msg)); |
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143 | |
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144 | path = payload + sizeof(msg); |
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145 | token = path + strlen(path) + 1; |
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146 | |
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147 | xenstore_buf->rsp_cons += msg.len + sizeof(msg); |
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148 | free(payload); |
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149 | wake_up(&watch_queue); |
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150 | } |
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151 | |
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152 | else |
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153 | { |
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154 | req_info[msg.req_id].reply = malloc(sizeof(msg) + msg.len); |
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155 | memcpy_from_ring(xenstore_buf->rsp, |
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156 | req_info[msg.req_id].reply, |
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157 | MASK_XENSTORE_IDX(xenstore_buf->rsp_cons), |
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158 | msg.len + sizeof(msg)); |
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159 | xenstore_buf->rsp_cons += msg.len + sizeof(msg); |
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160 | wake_up(&req_info[msg.req_id].waitq); |
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161 | } |
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162 | } |
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163 | } |
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164 | } |
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165 | |
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166 | static void xenbus_evtchn_handler(evtchn_port_t port, struct pt_regs *regs, |
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167 | void *ign) |
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168 | { |
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169 | wake_up(&xb_waitq); |
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170 | } |
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171 | |
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172 | static int nr_live_reqs; |
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173 | static spinlock_t req_lock = SPIN_LOCK_UNLOCKED; |
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174 | static DECLARE_WAIT_QUEUE_HEAD(req_wq); |
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175 | |
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176 | /* Release a xenbus identifier */ |
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177 | static void release_xenbus_id(int id) |
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178 | { |
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179 | BUG_ON(!req_info[id].in_use); |
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180 | spin_lock(&req_lock); |
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181 | req_info[id].in_use = 0; |
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182 | nr_live_reqs--; |
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183 | req_info[id].in_use = 0; |
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184 | if (nr_live_reqs == NR_REQS - 1) |
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185 | wake_up(&req_wq); |
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186 | spin_unlock(&req_lock); |
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187 | } |
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188 | |
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189 | /* Allocate an identifier for a xenbus request. Blocks if none are |
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190 | available. */ |
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191 | static int allocate_xenbus_id(void) |
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192 | { |
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193 | static int probe; |
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194 | int o_probe; |
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195 | |
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196 | while (1) |
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197 | { |
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198 | spin_lock(&req_lock); |
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199 | if (nr_live_reqs < NR_REQS) |
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200 | break; |
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201 | spin_unlock(&req_lock); |
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202 | wait_event(req_wq, (nr_live_reqs < NR_REQS)); |
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203 | } |
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204 | |
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205 | o_probe = probe; |
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206 | for (;;) |
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207 | { |
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208 | if (!req_info[o_probe].in_use) |
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209 | break; |
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210 | o_probe = (o_probe + 1) % NR_REQS; |
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211 | BUG_ON(o_probe == probe); |
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212 | } |
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213 | nr_live_reqs++; |
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214 | req_info[o_probe].in_use = 1; |
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215 | probe = (o_probe + 1) % NR_REQS; |
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216 | spin_unlock(&req_lock); |
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217 | init_waitqueue_head(&req_info[o_probe].waitq); |
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218 | |
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219 | return o_probe; |
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220 | } |
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221 | |
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222 | /* Initialise xenbus. */ |
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223 | void init_xenbus(void) |
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224 | { |
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225 | int err; |
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226 | printk("Initialising xenbus\n"); |
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227 | DEBUG("init_xenbus called.\n"); |
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228 | xenstore_buf = mfn_to_virt(start_info.store_mfn); |
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229 | create_thread("xenstore", xenbus_thread_func, NULL); |
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230 | DEBUG("buf at %p.\n", xenstore_buf); |
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231 | err = bind_evtchn(start_info.store_evtchn, |
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232 | xenbus_evtchn_handler, |
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233 | NULL); |
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234 | DEBUG("xenbus on irq %d\n", err); |
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235 | } |
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236 | |
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237 | struct write_req { |
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238 | const void *data; |
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239 | unsigned len; |
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240 | }; |
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241 | |
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242 | /* Send data to xenbus. This can block. All of the requests are seen |
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243 | by xenbus as if sent atomically. The header is added |
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244 | automatically, using type %type, req_id %req_id, and trans_id |
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245 | %trans_id. */ |
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246 | static void xb_write(int type, int req_id, xenbus_transaction_t trans_id, |
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247 | const struct write_req *req, int nr_reqs) |
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248 | { |
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249 | XENSTORE_RING_IDX prod; |
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250 | int r; |
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251 | int len = 0; |
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252 | const struct write_req *cur_req; |
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253 | int req_off; |
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254 | int total_off; |
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255 | int this_chunk; |
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256 | struct xsd_sockmsg m = {.type = type, .req_id = req_id, |
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257 | .tx_id = trans_id }; |
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258 | struct write_req header_req = { &m, sizeof(m) }; |
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259 | |
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260 | for (r = 0; r < nr_reqs; r++) |
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261 | len += req[r].len; |
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262 | m.len = len; |
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263 | len += sizeof(m); |
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264 | |
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265 | cur_req = &header_req; |
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266 | |
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267 | BUG_ON(len > XENSTORE_RING_SIZE); |
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268 | /* Wait for the ring to drain to the point where we can send the |
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269 | message. */ |
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270 | prod = xenstore_buf->req_prod; |
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271 | if (prod + len - xenstore_buf->req_cons > XENSTORE_RING_SIZE) |
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272 | { |
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273 | /* Wait for there to be space on the ring */ |
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274 | DEBUG("prod %d, len %d, cons %d, size %d; waiting.\n", |
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275 | prod, len, xenstore_buf->req_cons, XENSTORE_RING_SIZE); |
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276 | wait_event(xb_waitq, |
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277 | xenstore_buf->req_prod + len - xenstore_buf->req_cons <= |
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278 | XENSTORE_RING_SIZE); |
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279 | DEBUG("Back from wait.\n"); |
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280 | prod = xenstore_buf->req_prod; |
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281 | } |
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282 | |
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283 | /* We're now guaranteed to be able to send the message without |
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284 | overflowing the ring. Do so. */ |
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285 | total_off = 0; |
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286 | req_off = 0; |
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287 | while (total_off < len) |
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288 | { |
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289 | this_chunk = min(cur_req->len - req_off, |
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290 | XENSTORE_RING_SIZE - MASK_XENSTORE_IDX(prod)); |
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291 | memcpy((char *)xenstore_buf->req + MASK_XENSTORE_IDX(prod), |
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292 | (char *)cur_req->data + req_off, this_chunk); |
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293 | prod += this_chunk; |
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294 | req_off += this_chunk; |
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295 | total_off += this_chunk; |
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296 | if (req_off == cur_req->len) |
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297 | { |
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298 | req_off = 0; |
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299 | if (cur_req == &header_req) |
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300 | cur_req = req; |
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301 | else |
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302 | cur_req++; |
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303 | } |
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304 | } |
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305 | |
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306 | DEBUG("Complete main loop of xb_write.\n"); |
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307 | BUG_ON(req_off != 0); |
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308 | BUG_ON(total_off != len); |
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309 | BUG_ON(prod > xenstore_buf->req_cons + XENSTORE_RING_SIZE); |
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310 | |
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311 | /* Remote must see entire message before updating indexes */ |
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312 | wmb(); |
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313 | |
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314 | xenstore_buf->req_prod += len; |
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315 | |
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316 | /* Send evtchn to notify remote */ |
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317 | notify_remote_via_evtchn(start_info.store_evtchn); |
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318 | } |
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319 | |
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320 | /* Send a mesasge to xenbus, in the same fashion as xb_write, and |
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321 | block waiting for a reply. The reply is malloced and should be |
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322 | freed by the caller. */ |
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323 | static struct xsd_sockmsg * |
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324 | xenbus_msg_reply(int type, |
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325 | xenbus_transaction_t trans, |
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326 | struct write_req *io, |
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327 | int nr_reqs) |
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328 | { |
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329 | int id; |
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330 | DEFINE_WAIT(w); |
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331 | struct xsd_sockmsg *rep; |
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332 | |
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333 | id = allocate_xenbus_id(); |
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334 | add_waiter(w, req_info[id].waitq); |
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335 | |
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336 | xb_write(type, id, trans, io, nr_reqs); |
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337 | |
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338 | schedule(); |
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339 | remove_waiter(w); |
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340 | wake(current); |
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341 | |
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342 | rep = req_info[id].reply; |
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343 | BUG_ON(rep->req_id != id); |
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344 | release_xenbus_id(id); |
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345 | return rep; |
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346 | } |
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347 | |
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348 | static char *errmsg(struct xsd_sockmsg *rep) |
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349 | { |
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350 | if (!rep) { |
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351 | char msg[] = "No reply"; |
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352 | size_t len = strlen(msg) + 1; |
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353 | return memcpy(malloc(len), msg, len); |
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354 | } |
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355 | if (rep->type != XS_ERROR) |
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356 | return NULL; |
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357 | char *res = malloc(rep->len + 1); |
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358 | memcpy(res, rep + 1, rep->len); |
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359 | res[rep->len] = 0; |
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360 | free(rep); |
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361 | return res; |
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362 | } |
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363 | |
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364 | /* Send a debug message to xenbus. Can block. */ |
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365 | static void xenbus_debug_msg(const char *msg) |
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366 | { |
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367 | int len = strlen(msg); |
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368 | struct write_req req[] = { |
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369 | { "print", sizeof("print") }, |
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370 | { msg, len }, |
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371 | { "", 1 }}; |
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372 | struct xsd_sockmsg *reply; |
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373 | |
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374 | reply = xenbus_msg_reply(XS_DEBUG, 0, req, ARRAY_SIZE(req)); |
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375 | DEBUG("Got a reply, type %d, id %d, len %d.\n", |
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376 | reply->type, reply->req_id, reply->len); |
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377 | } |
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378 | |
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379 | /* List the contents of a directory. Returns a malloc()ed array of |
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380 | pointers to malloc()ed strings. The array is NULL terminated. May |
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381 | block. */ |
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382 | char *xenbus_ls(xenbus_transaction_t xbt, const char *pre, char ***contents) |
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383 | { |
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384 | struct xsd_sockmsg *reply, *repmsg; |
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385 | struct write_req req[] = { { pre, strlen(pre)+1 } }; |
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386 | int nr_elems, x, i; |
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387 | char **res; |
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388 | |
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389 | repmsg = xenbus_msg_reply(XS_DIRECTORY, xbt, req, ARRAY_SIZE(req)); |
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390 | char *msg = errmsg(repmsg); |
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391 | if (msg) { |
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392 | *contents = NULL; |
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393 | return msg; |
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394 | } |
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395 | reply = repmsg + 1; |
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396 | for (x = nr_elems = 0; x < repmsg->len; x++) |
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397 | nr_elems += (((char *)reply)[x] == 0); |
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398 | res = malloc(sizeof(res[0]) * (nr_elems + 1)); |
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399 | for (x = i = 0; i < nr_elems; i++) { |
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400 | int l = strlen((char *)reply + x); |
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401 | res[i] = malloc(l + 1); |
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402 | memcpy(res[i], (char *)reply + x, l + 1); |
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403 | x += l + 1; |
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404 | } |
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405 | res[i] = NULL; |
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406 | free(repmsg); |
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407 | *contents = res; |
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408 | return NULL; |
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409 | } |
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410 | |
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411 | char *xenbus_read(xenbus_transaction_t xbt, const char *path, char **value) |
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412 | { |
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413 | struct write_req req[] = { {path, strlen(path) + 1} }; |
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414 | struct xsd_sockmsg *rep; |
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415 | char *res; |
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416 | rep = xenbus_msg_reply(XS_READ, xbt, req, ARRAY_SIZE(req)); |
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417 | char *msg = errmsg(rep); |
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418 | if (msg) { |
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419 | *value = NULL; |
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420 | return msg; |
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421 | } |
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422 | res = malloc(rep->len + 1); |
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423 | memcpy(res, rep + 1, rep->len); |
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424 | res[rep->len] = 0; |
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425 | free(rep); |
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426 | *value = res; |
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427 | return NULL; |
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428 | } |
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429 | |
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430 | char *xenbus_write(xenbus_transaction_t xbt, const char *path, const char *value) |
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431 | { |
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432 | struct write_req req[] = { |
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433 | {path, strlen(path) + 1}, |
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434 | {value, strlen(value) + 1}, |
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435 | }; |
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436 | struct xsd_sockmsg *rep; |
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437 | rep = xenbus_msg_reply(XS_WRITE, xbt, req, ARRAY_SIZE(req)); |
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438 | char *msg = errmsg(rep); |
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439 | if (msg) return msg; |
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440 | free(rep); |
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441 | return NULL; |
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442 | } |
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443 | |
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444 | char* xenbus_watch_path( xenbus_transaction_t xbt, const char *path) |
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445 | { |
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446 | /* in the future one could have multiple watch queues, and use |
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447 | * the token for demuxing. For now the token is 0. */ |
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448 | |
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449 | struct xsd_sockmsg *rep; |
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450 | |
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451 | struct write_req req[] = { |
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452 | {path, strlen(path) + 1}, |
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453 | {"0",2 }, |
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454 | }; |
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455 | |
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456 | rep = xenbus_msg_reply(XS_WATCH, xbt, req, ARRAY_SIZE(req)); |
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457 | |
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458 | char *msg = errmsg(rep); |
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459 | if (msg) return msg; |
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460 | free(rep); |
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461 | |
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462 | return NULL; |
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463 | } |
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464 | |
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465 | char *xenbus_rm(xenbus_transaction_t xbt, const char *path) |
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466 | { |
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467 | struct write_req req[] = { {path, strlen(path) + 1} }; |
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468 | struct xsd_sockmsg *rep; |
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469 | rep = xenbus_msg_reply(XS_RM, xbt, req, ARRAY_SIZE(req)); |
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470 | char *msg = errmsg(rep); |
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471 | if (msg) |
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472 | return msg; |
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473 | free(rep); |
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474 | return NULL; |
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475 | } |
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476 | |
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477 | char *xenbus_get_perms(xenbus_transaction_t xbt, const char *path, char **value) |
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478 | { |
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479 | struct write_req req[] = { {path, strlen(path) + 1} }; |
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480 | struct xsd_sockmsg *rep; |
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481 | char *res; |
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482 | rep = xenbus_msg_reply(XS_GET_PERMS, xbt, req, ARRAY_SIZE(req)); |
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483 | char *msg = errmsg(rep); |
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484 | if (msg) { |
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485 | *value = NULL; |
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486 | return msg; |
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487 | } |
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488 | res = malloc(rep->len + 1); |
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489 | memcpy(res, rep + 1, rep->len); |
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490 | res[rep->len] = 0; |
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491 | free(rep); |
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492 | *value = res; |
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493 | return NULL; |
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494 | } |
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495 | |
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496 | #define PERM_MAX_SIZE 32 |
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497 | char *xenbus_set_perms(xenbus_transaction_t xbt, const char *path, domid_t dom, char perm) |
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498 | { |
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499 | char value[PERM_MAX_SIZE]; |
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500 | snprintf(value, PERM_MAX_SIZE, "%c%hu", perm, dom); |
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501 | struct write_req req[] = { |
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502 | {path, strlen(path) + 1}, |
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503 | {value, strlen(value) + 1}, |
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504 | }; |
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505 | struct xsd_sockmsg *rep; |
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506 | rep = xenbus_msg_reply(XS_SET_PERMS, xbt, req, ARRAY_SIZE(req)); |
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507 | char *msg = errmsg(rep); |
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508 | if (msg) |
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509 | return msg; |
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510 | free(rep); |
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511 | return NULL; |
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512 | } |
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513 | |
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514 | char *xenbus_transaction_start(xenbus_transaction_t *xbt) |
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515 | { |
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516 | /* xenstored becomes angry if you send a length 0 message, so just |
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517 | shove a nul terminator on the end */ |
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518 | struct write_req req = { "", 1}; |
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519 | struct xsd_sockmsg *rep; |
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520 | char *err; |
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521 | |
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522 | rep = xenbus_msg_reply(XS_TRANSACTION_START, 0, &req, 1); |
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523 | err = errmsg(rep); |
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524 | if (err) |
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525 | return err; |
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526 | sscanf((char *)(rep + 1), "%u", xbt); |
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527 | free(rep); |
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528 | return NULL; |
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529 | } |
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530 | |
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531 | char * |
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532 | xenbus_transaction_end(xenbus_transaction_t t, int abort, int *retry) |
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533 | { |
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534 | struct xsd_sockmsg *rep; |
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535 | struct write_req req; |
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536 | char *err; |
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537 | |
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538 | *retry = 0; |
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539 | |
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540 | req.data = abort ? "F" : "T"; |
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541 | req.len = 2; |
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542 | rep = xenbus_msg_reply(XS_TRANSACTION_END, t, &req, 1); |
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543 | err = errmsg(rep); |
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544 | if (err) { |
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545 | if (!strcmp(err, "EAGAIN")) { |
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546 | *retry = 1; |
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547 | free(err); |
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548 | return NULL; |
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549 | } else { |
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550 | return err; |
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551 | } |
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552 | } |
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553 | free(rep); |
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554 | return NULL; |
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555 | } |
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556 | |
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557 | int xenbus_read_integer(char *path) |
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558 | { |
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559 | char *res, *buf; |
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560 | int t; |
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561 | |
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562 | res = xenbus_read(XBT_NIL, path, &buf); |
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563 | if (res) { |
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564 | printk("Failed to read %s.\n", path); |
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565 | free(res); |
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566 | return -1; |
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567 | } |
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568 | sscanf(buf, "%d", &t); |
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569 | free(buf); |
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570 | return t; |
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571 | } |
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572 | |
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573 | static void do_ls_test(const char *pre) |
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574 | { |
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575 | char **dirs; |
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576 | int x; |
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577 | |
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578 | DEBUG("ls %s...\n", pre); |
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579 | char *msg = xenbus_ls(XBT_NIL, pre, &dirs); |
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580 | if (msg) { |
---|
581 | DEBUG("Error in xenbus ls: %s\n", msg); |
---|
582 | free(msg); |
---|
583 | return; |
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584 | } |
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585 | for (x = 0; dirs[x]; x++) |
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586 | { |
---|
587 | DEBUG("ls %s[%d] -> %s\n", pre, x, dirs[x]); |
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588 | free(dirs[x]); |
---|
589 | } |
---|
590 | free(dirs); |
---|
591 | } |
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592 | |
---|
593 | static void do_read_test(const char *path) |
---|
594 | { |
---|
595 | char *res; |
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596 | DEBUG("Read %s...\n", path); |
---|
597 | char *msg = xenbus_read(XBT_NIL, path, &res); |
---|
598 | if (msg) { |
---|
599 | DEBUG("Error in xenbus read: %s\n", msg); |
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600 | free(msg); |
---|
601 | return; |
---|
602 | } |
---|
603 | DEBUG("Read %s -> %s.\n", path, res); |
---|
604 | free(res); |
---|
605 | } |
---|
606 | |
---|
607 | static void do_write_test(const char *path, const char *val) |
---|
608 | { |
---|
609 | DEBUG("Write %s to %s...\n", val, path); |
---|
610 | char *msg = xenbus_write(XBT_NIL, path, val); |
---|
611 | if (msg) { |
---|
612 | DEBUG("Result %s\n", msg); |
---|
613 | free(msg); |
---|
614 | } else { |
---|
615 | DEBUG("Success.\n"); |
---|
616 | } |
---|
617 | } |
---|
618 | |
---|
619 | static void do_rm_test(const char *path) |
---|
620 | { |
---|
621 | DEBUG("rm %s...\n", path); |
---|
622 | char *msg = xenbus_rm(XBT_NIL, path); |
---|
623 | if (msg) { |
---|
624 | DEBUG("Result %s\n", msg); |
---|
625 | free(msg); |
---|
626 | } else { |
---|
627 | DEBUG("Success.\n"); |
---|
628 | } |
---|
629 | } |
---|
630 | |
---|
631 | /* Simple testing thing */ |
---|
632 | void test_xenbus(void) |
---|
633 | { |
---|
634 | DEBUG("Doing xenbus test.\n"); |
---|
635 | xenbus_debug_msg("Testing xenbus...\n"); |
---|
636 | |
---|
637 | DEBUG("Doing ls test.\n"); |
---|
638 | do_ls_test("device"); |
---|
639 | do_ls_test("device/vif"); |
---|
640 | do_ls_test("device/vif/0"); |
---|
641 | |
---|
642 | DEBUG("Doing read test.\n"); |
---|
643 | do_read_test("device/vif/0/mac"); |
---|
644 | do_read_test("device/vif/0/backend"); |
---|
645 | |
---|
646 | DEBUG("Doing write test.\n"); |
---|
647 | do_write_test("device/vif/0/flibble", "flobble"); |
---|
648 | do_read_test("device/vif/0/flibble"); |
---|
649 | do_write_test("device/vif/0/flibble", "widget"); |
---|
650 | do_read_test("device/vif/0/flibble"); |
---|
651 | |
---|
652 | DEBUG("Doing rm test.\n"); |
---|
653 | do_rm_test("device/vif/0/flibble"); |
---|
654 | do_read_test("device/vif/0/flibble"); |
---|
655 | DEBUG("(Should have said ENOENT)\n"); |
---|
656 | } |
---|
657 | |
---|
658 | /* |
---|
659 | * Local variables: |
---|
660 | * mode: C |
---|
661 | * c-basic-offset: 4 |
---|
662 | * End: |
---|
663 | */ |
---|