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Lines 64-69
struct fifoinfo {
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| 64 |
struct pipe *fi_pipe; |
64 |
struct pipe *fi_pipe; |
| 65 |
long fi_readers; |
65 |
long fi_readers; |
| 66 |
long fi_writers; |
66 |
long fi_writers; |
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67 |
long fi_rgen; |
| 68 |
long fi_wgen; |
| 67 |
}; |
69 |
}; |
| 68 |
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70 |
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| 69 |
static vop_print_t fifo_print; |
71 |
static vop_print_t fifo_print; |
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Lines 137-142
fifo_open(ap)
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| 137 |
struct thread *td; |
139 |
struct thread *td; |
| 138 |
struct fifoinfo *fip; |
140 |
struct fifoinfo *fip; |
| 139 |
struct pipe *fpipe; |
141 |
struct pipe *fpipe; |
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142 |
long gen; |
| 140 |
int error, stops_deferred; |
143 |
int error, stops_deferred; |
| 141 |
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144 |
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| 142 |
vp = ap->a_vp; |
145 |
vp = ap->a_vp; |
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Lines 164-169
fifo_open(ap)
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| 164 |
PIPE_LOCK(fpipe); |
167 |
PIPE_LOCK(fpipe); |
| 165 |
if (ap->a_mode & FREAD) { |
168 |
if (ap->a_mode & FREAD) { |
| 166 |
fip->fi_readers++; |
169 |
fip->fi_readers++; |
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170 |
fip->fi_rgen++; |
| 167 |
if (fip->fi_readers == 1) { |
171 |
if (fip->fi_readers == 1) { |
| 168 |
fpipe->pipe_state &= ~PIPE_EOF; |
172 |
fpipe->pipe_state &= ~PIPE_EOF; |
| 169 |
if (fip->fi_writers > 0) |
173 |
if (fip->fi_writers > 0) |
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Lines 179-184
fifo_open(ap)
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| 179 |
return (ENXIO); |
183 |
return (ENXIO); |
| 180 |
} |
184 |
} |
| 181 |
fip->fi_writers++; |
185 |
fip->fi_writers++; |
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186 |
fip->fi_wgen++; |
| 182 |
if (fip->fi_writers == 1) { |
187 |
if (fip->fi_writers == 1) { |
| 183 |
fpipe->pipe_state &= ~PIPE_EOF; |
188 |
fpipe->pipe_state &= ~PIPE_EOF; |
| 184 |
if (fip->fi_readers > 0) |
189 |
if (fip->fi_readers > 0) |
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Lines 187-192
fifo_open(ap)
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| 187 |
} |
192 |
} |
| 188 |
if ((ap->a_mode & O_NONBLOCK) == 0) { |
193 |
if ((ap->a_mode & O_NONBLOCK) == 0) { |
| 189 |
if ((ap->a_mode & FREAD) && fip->fi_writers == 0) { |
194 |
if ((ap->a_mode & FREAD) && fip->fi_writers == 0) { |
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195 |
gen = fip->fi_wgen; |
| 190 |
VOP_UNLOCK(vp, 0); |
196 |
VOP_UNLOCK(vp, 0); |
| 191 |
stops_deferred = sigallowstop(); |
197 |
stops_deferred = sigallowstop(); |
| 192 |
error = msleep(&fip->fi_readers, PIPE_MTX(fpipe), |
198 |
error = msleep(&fip->fi_readers, PIPE_MTX(fpipe), |
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Lines 194-200
fifo_open(ap)
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| 194 |
if (stops_deferred) |
200 |
if (stops_deferred) |
| 195 |
sigdeferstop(); |
201 |
sigdeferstop(); |
| 196 |
vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); |
202 |
vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); |
| 197 |
if (error) { |
203 |
if (error != 0 && gen == fip->fi_wgen) { |
| 198 |
fip->fi_readers--; |
204 |
fip->fi_readers--; |
| 199 |
if (fip->fi_readers == 0) { |
205 |
if (fip->fi_readers == 0) { |
| 200 |
PIPE_LOCK(fpipe); |
206 |
PIPE_LOCK(fpipe); |
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Lines 214-219
fifo_open(ap)
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| 214 |
*/ |
220 |
*/ |
| 215 |
} |
221 |
} |
| 216 |
if ((ap->a_mode & FWRITE) && fip->fi_readers == 0) { |
222 |
if ((ap->a_mode & FWRITE) && fip->fi_readers == 0) { |
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223 |
gen = fip->fi_rgen; |
| 217 |
VOP_UNLOCK(vp, 0); |
224 |
VOP_UNLOCK(vp, 0); |
| 218 |
stops_deferred = sigallowstop(); |
225 |
stops_deferred = sigallowstop(); |
| 219 |
error = msleep(&fip->fi_writers, PIPE_MTX(fpipe), |
226 |
error = msleep(&fip->fi_writers, PIPE_MTX(fpipe), |
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Lines 221-227
fifo_open(ap)
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| 221 |
if (stops_deferred) |
228 |
if (stops_deferred) |
| 222 |
sigdeferstop(); |
229 |
sigdeferstop(); |
| 223 |
vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); |
230 |
vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); |
| 224 |
if (error) { |
231 |
if (error != 0 && gen == fip->fi_rgen) { |
| 225 |
fip->fi_writers--; |
232 |
fip->fi_writers--; |
| 226 |
if (fip->fi_writers == 0) { |
233 |
if (fip->fi_writers == 0) { |
| 227 |
PIPE_LOCK(fpipe); |
234 |
PIPE_LOCK(fpipe); |