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-rw-r--r--fs/autofs/waitq.c205
1 files changed, 0 insertions, 205 deletions
diff --git a/fs/autofs/waitq.c b/fs/autofs/waitq.c
deleted file mode 100644
index be46805972f0..000000000000
--- a/fs/autofs/waitq.c
+++ /dev/null
@@ -1,205 +0,0 @@
1/* -*- linux-c -*- --------------------------------------------------------- *
2 *
3 * linux/fs/autofs/waitq.c
4 *
5 * Copyright 1997-1998 Transmeta Corporation -- All Rights Reserved
6 *
7 * This file is part of the Linux kernel and is made available under
8 * the terms of the GNU General Public License, version 2, or at your
9 * option, any later version, incorporated herein by reference.
10 *
11 * ------------------------------------------------------------------------- */
12
13#include <linux/slab.h>
14#include <linux/time.h>
15#include <linux/signal.h>
16#include <linux/file.h>
17#include "autofs_i.h"
18
19/* We make this a static variable rather than a part of the superblock; it
20 is better if we don't reassign numbers easily even across filesystems */
21static autofs_wqt_t autofs_next_wait_queue = 1;
22
23/* These are the signals we allow interrupting a pending mount */
24#define SHUTDOWN_SIGS (sigmask(SIGKILL) | sigmask(SIGINT) | sigmask(SIGQUIT))
25
26void autofs_catatonic_mode(struct autofs_sb_info *sbi)
27{
28 struct autofs_wait_queue *wq, *nwq;
29
30 DPRINTK(("autofs: entering catatonic mode\n"));
31
32 sbi->catatonic = 1;
33 wq = sbi->queues;
34 sbi->queues = NULL; /* Erase all wait queues */
35 while ( wq ) {
36 nwq = wq->next;
37 wq->status = -ENOENT; /* Magic is gone - report failure */
38 kfree(wq->name);
39 wq->name = NULL;
40 wake_up(&wq->queue);
41 wq = nwq;
42 }
43 fput(sbi->pipe); /* Close the pipe */
44 sbi->pipe = NULL;
45 autofs_hash_dputall(&sbi->dirhash); /* Remove all dentry pointers */
46}
47
48static int autofs_write(struct file *file, const void *addr, int bytes)
49{
50 unsigned long sigpipe, flags;
51 mm_segment_t fs;
52 const char *data = (const char *)addr;
53 ssize_t wr = 0;
54
55 /** WARNING: this is not safe for writing more than PIPE_BUF bytes! **/
56
57 sigpipe = sigismember(&current->pending.signal, SIGPIPE);
58
59 /* Save pointer to user space and point back to kernel space */
60 fs = get_fs();
61 set_fs(KERNEL_DS);
62
63 while (bytes &&
64 (wr = file->f_op->write(file,data,bytes,&file->f_pos)) > 0) {
65 data += wr;
66 bytes -= wr;
67 }
68
69 set_fs(fs);
70
71 /* Keep the currently executing process from receiving a
72 SIGPIPE unless it was already supposed to get one */
73 if (wr == -EPIPE && !sigpipe) {
74 spin_lock_irqsave(&current->sighand->siglock, flags);
75 sigdelset(&current->pending.signal, SIGPIPE);
76 recalc_sigpending();
77 spin_unlock_irqrestore(&current->sighand->siglock, flags);
78 }
79
80 return (bytes > 0);
81}
82
83static void autofs_notify_daemon(struct autofs_sb_info *sbi, struct autofs_wait_queue *wq)
84{
85 struct autofs_packet_missing pkt;
86
87 DPRINTK(("autofs_wait: wait id = 0x%08lx, name = ", wq->wait_queue_token));
88 autofs_say(wq->name,wq->len);
89
90 memset(&pkt,0,sizeof pkt); /* For security reasons */
91
92 pkt.hdr.proto_version = AUTOFS_PROTO_VERSION;
93 pkt.hdr.type = autofs_ptype_missing;
94 pkt.wait_queue_token = wq->wait_queue_token;
95 pkt.len = wq->len;
96 memcpy(pkt.name, wq->name, pkt.len);
97 pkt.name[pkt.len] = '\0';
98
99 if ( autofs_write(sbi->pipe,&pkt,sizeof(struct autofs_packet_missing)) )
100 autofs_catatonic_mode(sbi);
101}
102
103int autofs_wait(struct autofs_sb_info *sbi, struct qstr *name)
104{
105 struct autofs_wait_queue *wq;
106 int status;
107
108 /* In catatonic mode, we don't wait for nobody */
109 if ( sbi->catatonic )
110 return -ENOENT;
111
112 /* We shouldn't be able to get here, but just in case */
113 if ( name->len > NAME_MAX )
114 return -ENOENT;
115
116 for ( wq = sbi->queues ; wq ; wq = wq->next ) {
117 if ( wq->hash == name->hash &&
118 wq->len == name->len &&
119 wq->name && !memcmp(wq->name,name->name,name->len) )
120 break;
121 }
122
123 if ( !wq ) {
124 /* Create a new wait queue */
125 wq = kmalloc(sizeof(struct autofs_wait_queue),GFP_KERNEL);
126 if ( !wq )
127 return -ENOMEM;
128
129 wq->name = kmalloc(name->len,GFP_KERNEL);
130 if ( !wq->name ) {
131 kfree(wq);
132 return -ENOMEM;
133 }
134 wq->wait_queue_token = autofs_next_wait_queue++;
135 init_waitqueue_head(&wq->queue);
136 wq->hash = name->hash;
137 wq->len = name->len;
138 wq->status = -EINTR; /* Status return if interrupted */
139 memcpy(wq->name, name->name, name->len);
140 wq->next = sbi->queues;
141 sbi->queues = wq;
142
143 /* autofs_notify_daemon() may block */
144 wq->wait_ctr = 2;
145 autofs_notify_daemon(sbi,wq);
146 } else
147 wq->wait_ctr++;
148
149 /* wq->name is NULL if and only if the lock is already released */
150
151 if ( sbi->catatonic ) {
152 /* We might have slept, so check again for catatonic mode */
153 wq->status = -ENOENT;
154 kfree(wq->name);
155 wq->name = NULL;
156 }
157
158 if ( wq->name ) {
159 /* Block all but "shutdown" signals while waiting */
160 sigset_t sigmask;
161
162 siginitsetinv(&sigmask, SHUTDOWN_SIGS);
163 sigprocmask(SIG_BLOCK, &sigmask, &sigmask);
164
165 interruptible_sleep_on(&wq->queue);
166
167 sigprocmask(SIG_SETMASK, &sigmask, NULL);
168 } else {
169 DPRINTK(("autofs_wait: skipped sleeping\n"));
170 }
171
172 status = wq->status;
173
174 if ( ! --wq->wait_ctr ) /* Are we the last process to need status? */
175 kfree(wq);
176
177 return status;
178}
179
180
181int autofs_wait_release(struct autofs_sb_info *sbi, autofs_wqt_t wait_queue_token, int status)
182{
183 struct autofs_wait_queue *wq, **wql;
184
185 for (wql = &sbi->queues; (wq = *wql) != NULL; wql = &wq->next) {
186 if ( wq->wait_queue_token == wait_queue_token )
187 break;
188 }
189 if ( !wq )
190 return -EINVAL;
191
192 *wql = wq->next; /* Unlink from chain */
193 kfree(wq->name);
194 wq->name = NULL; /* Do not wait on this queue */
195
196 wq->status = status;
197
198 if ( ! --wq->wait_ctr ) /* Is anyone still waiting for this guy? */
199 kfree(wq);
200 else
201 wake_up(&wq->queue);
202
203 return 0;
204}
205
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