1  // SPDX-License-Identifier: GPL-2.0-only
2  /*
3   * Error string handling
4   *
5   * Plan 9 uses error strings, Unix uses error numbers.  These functions
6   * try to help manage that and provide for dynamically adding error
7   * mappings.
8   *
9   *  Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
10   *  Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
11   */
12  
13  #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
14  
15  #include <linux/module.h>
16  #include <linux/list.h>
17  #include <linux/jhash.h>
18  #include <linux/errno.h>
19  #include <net/9p/9p.h>
20  
21  /**
22   * struct errormap - map string errors from Plan 9 to Linux numeric ids
23   * @name: string sent over 9P
24   * @val: numeric id most closely representing @name
25   * @namelen: length of string
26   * @list: hash-table list for string lookup
27   */
28  struct errormap {
29  	char *name;
30  	int val;
31  
32  	int namelen;
33  	struct hlist_node list;
34  };
35  
36  #define ERRHASHSZ		32
37  static struct hlist_head hash_errmap[ERRHASHSZ];
38  
39  /* FixMe - reduce to a reasonable size */
40  static struct errormap errmap[] = {
41  	{"Operation not permitted", EPERM},
42  	{"wstat prohibited", EPERM},
43  	{"No such file or directory", ENOENT},
44  	{"directory entry not found", ENOENT},
45  	{"file not found", ENOENT},
46  	{"Interrupted system call", EINTR},
47  	{"Input/output error", EIO},
48  	{"No such device or address", ENXIO},
49  	{"Argument list too long", E2BIG},
50  	{"Bad file descriptor", EBADF},
51  	{"Resource temporarily unavailable", EAGAIN},
52  	{"Cannot allocate memory", ENOMEM},
53  	{"Permission denied", EACCES},
54  	{"Bad address", EFAULT},
55  	{"Block device required", ENOTBLK},
56  	{"Device or resource busy", EBUSY},
57  	{"File exists", EEXIST},
58  	{"Invalid cross-device link", EXDEV},
59  	{"No such device", ENODEV},
60  	{"Not a directory", ENOTDIR},
61  	{"Is a directory", EISDIR},
62  	{"Invalid argument", EINVAL},
63  	{"Too many open files in system", ENFILE},
64  	{"Too many open files", EMFILE},
65  	{"Text file busy", ETXTBSY},
66  	{"File too large", EFBIG},
67  	{"No space left on device", ENOSPC},
68  	{"Illegal seek", ESPIPE},
69  	{"Read-only file system", EROFS},
70  	{"Too many links", EMLINK},
71  	{"Broken pipe", EPIPE},
72  	{"Numerical argument out of domain", EDOM},
73  	{"Numerical result out of range", ERANGE},
74  	{"Resource deadlock avoided", EDEADLK},
75  	{"File name too long", ENAMETOOLONG},
76  	{"No locks available", ENOLCK},
77  	{"Function not implemented", ENOSYS},
78  	{"Directory not empty", ENOTEMPTY},
79  	{"Too many levels of symbolic links", ELOOP},
80  	{"No message of desired type", ENOMSG},
81  	{"Identifier removed", EIDRM},
82  	{"No data available", ENODATA},
83  	{"Machine is not on the network", ENONET},
84  	{"Package not installed", ENOPKG},
85  	{"Object is remote", EREMOTE},
86  	{"Link has been severed", ENOLINK},
87  	{"Communication error on send", ECOMM},
88  	{"Protocol error", EPROTO},
89  	{"Bad message", EBADMSG},
90  	{"File descriptor in bad state", EBADFD},
91  	{"Streams pipe error", ESTRPIPE},
92  	{"Too many users", EUSERS},
93  	{"Socket operation on non-socket", ENOTSOCK},
94  	{"Message too long", EMSGSIZE},
95  	{"Protocol not available", ENOPROTOOPT},
96  	{"Protocol not supported", EPROTONOSUPPORT},
97  	{"Socket type not supported", ESOCKTNOSUPPORT},
98  	{"Operation not supported", EOPNOTSUPP},
99  	{"Protocol family not supported", EPFNOSUPPORT},
100  	{"Network is down", ENETDOWN},
101  	{"Network is unreachable", ENETUNREACH},
102  	{"Network dropped connection on reset", ENETRESET},
103  	{"Software caused connection abort", ECONNABORTED},
104  	{"Connection reset by peer", ECONNRESET},
105  	{"No buffer space available", ENOBUFS},
106  	{"Transport endpoint is already connected", EISCONN},
107  	{"Transport endpoint is not connected", ENOTCONN},
108  	{"Cannot send after transport endpoint shutdown", ESHUTDOWN},
109  	{"Connection timed out", ETIMEDOUT},
110  	{"Connection refused", ECONNREFUSED},
111  	{"Host is down", EHOSTDOWN},
112  	{"No route to host", EHOSTUNREACH},
113  	{"Operation already in progress", EALREADY},
114  	{"Operation now in progress", EINPROGRESS},
115  	{"Is a named type file", EISNAM},
116  	{"Remote I/O error", EREMOTEIO},
117  	{"Disk quota exceeded", EDQUOT},
118  /* errors from fossil, vacfs, and u9fs */
119  	{"fid unknown or out of range", EBADF},
120  	{"permission denied", EACCES},
121  	{"file does not exist", ENOENT},
122  	{"authentication failed", ECONNREFUSED},
123  	{"bad offset in directory read", ESPIPE},
124  	{"bad use of fid", EBADF},
125  	{"wstat can't convert between files and directories", EPERM},
126  	{"directory is not empty", ENOTEMPTY},
127  	{"file exists", EEXIST},
128  	{"file already exists", EEXIST},
129  	{"file or directory already exists", EEXIST},
130  	{"fid already in use", EBADF},
131  	{"file in use", ETXTBSY},
132  	{"i/o error", EIO},
133  	{"file already open for I/O", ETXTBSY},
134  	{"illegal mode", EINVAL},
135  	{"illegal name", ENAMETOOLONG},
136  	{"not a directory", ENOTDIR},
137  	{"not a member of proposed group", EPERM},
138  	{"not owner", EACCES},
139  	{"only owner can change group in wstat", EACCES},
140  	{"read only file system", EROFS},
141  	{"no access to special file", EPERM},
142  	{"i/o count too large", EIO},
143  	{"unknown group", EINVAL},
144  	{"unknown user", EINVAL},
145  	{"bogus wstat buffer", EPROTO},
146  	{"exclusive use file already open", EAGAIN},
147  	{"corrupted directory entry", EIO},
148  	{"corrupted file entry", EIO},
149  	{"corrupted block label", EIO},
150  	{"corrupted meta data", EIO},
151  	{"illegal offset", EINVAL},
152  	{"illegal path element", ENOENT},
153  	{"root of file system is corrupted", EIO},
154  	{"corrupted super block", EIO},
155  	{"protocol botch", EPROTO},
156  	{"file system is full", ENOSPC},
157  	{"file is in use", EAGAIN},
158  	{"directory entry is not allocated", ENOENT},
159  	{"file is read only", EROFS},
160  	{"file has been removed", EIDRM},
161  	{"only support truncation to zero length", EPERM},
162  	{"cannot remove root", EPERM},
163  	{"file too big", EFBIG},
164  	{"venti i/o error", EIO},
165  	/* these are not errors */
166  	{"u9fs rhostsauth: no authentication required", 0},
167  	{"u9fs authnone: no authentication required", 0},
168  	{NULL, -1}
169  };
170  
171  /**
172   * p9_error_init - preload mappings into hash list
173   *
174   */
175  
p9_error_init(void)176  int p9_error_init(void)
177  {
178  	struct errormap *c;
179  	int bucket;
180  
181  	/* initialize hash table */
182  	for (bucket = 0; bucket < ERRHASHSZ; bucket++)
183  		INIT_HLIST_HEAD(&hash_errmap[bucket]);
184  
185  	/* load initial error map into hash table */
186  	for (c = errmap; c->name; c++) {
187  		c->namelen = strlen(c->name);
188  		bucket = jhash(c->name, c->namelen, 0) % ERRHASHSZ;
189  		INIT_HLIST_NODE(&c->list);
190  		hlist_add_head(&c->list, &hash_errmap[bucket]);
191  	}
192  
193  	return 1;
194  }
195  EXPORT_SYMBOL(p9_error_init);
196  
197  /**
198   * p9_errstr2errno - convert error string to error number
199   * @errstr: error string
200   * @len: length of error string
201   *
202   */
203  
p9_errstr2errno(char * errstr,int len)204  int p9_errstr2errno(char *errstr, int len)
205  {
206  	int errno;
207  	struct errormap *c;
208  	int bucket;
209  
210  	errno = 0;
211  	c = NULL;
212  	bucket = jhash(errstr, len, 0) % ERRHASHSZ;
213  	hlist_for_each_entry(c, &hash_errmap[bucket], list) {
214  		if (c->namelen == len && !memcmp(c->name, errstr, len)) {
215  			errno = c->val;
216  			break;
217  		}
218  	}
219  
220  	if (errno == 0) {
221  		/* TODO: if error isn't found, add it dynamically */
222  		errstr[len] = 0;
223  		pr_err("%s: server reported unknown error %s\n",
224  		       __func__, errstr);
225  		errno = ESERVERFAULT;
226  	}
227  
228  	return -errno;
229  }
230  EXPORT_SYMBOL(p9_errstr2errno);
231