1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * linux/fs/9p/error.c
4  *
5  * Error string handling
6  *
7  * Plan 9 uses error strings, Unix uses error numbers.  These functions
8  * try to help manage that and provide for dynamically adding error
9  * mappings.
10  *
11  *  Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
12  *  Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
13  */
14 
15 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
16 
17 #include <linux/module.h>
18 #include <linux/list.h>
19 #include <linux/jhash.h>
20 #include <linux/errno.h>
21 #include <net/9p/9p.h>
22 
23 /**
24  * struct errormap - map string errors from Plan 9 to Linux numeric ids
25  * @name: string sent over 9P
26  * @val: numeric id most closely representing @name
27  * @namelen: length of string
28  * @list: hash-table list for string lookup
29  */
30 struct errormap {
31 	char *name;
32 	int val;
33 
34 	int namelen;
35 	struct hlist_node list;
36 };
37 
38 #define ERRHASHSZ		32
39 static struct hlist_head hash_errmap[ERRHASHSZ];
40 
41 /* FixMe - reduce to a reasonable size */
42 static struct errormap errmap[] = {
43 	{"Operation not permitted", EPERM},
44 	{"wstat prohibited", EPERM},
45 	{"No such file or directory", ENOENT},
46 	{"directory entry not found", ENOENT},
47 	{"file not found", ENOENT},
48 	{"Interrupted system call", EINTR},
49 	{"Input/output error", EIO},
50 	{"No such device or address", ENXIO},
51 	{"Argument list too long", E2BIG},
52 	{"Bad file descriptor", EBADF},
53 	{"Resource temporarily unavailable", EAGAIN},
54 	{"Cannot allocate memory", ENOMEM},
55 	{"Permission denied", EACCES},
56 	{"Bad address", EFAULT},
57 	{"Block device required", ENOTBLK},
58 	{"Device or resource busy", EBUSY},
59 	{"File exists", EEXIST},
60 	{"Invalid cross-device link", EXDEV},
61 	{"No such device", ENODEV},
62 	{"Not a directory", ENOTDIR},
63 	{"Is a directory", EISDIR},
64 	{"Invalid argument", EINVAL},
65 	{"Too many open files in system", ENFILE},
66 	{"Too many open files", EMFILE},
67 	{"Text file busy", ETXTBSY},
68 	{"File too large", EFBIG},
69 	{"No space left on device", ENOSPC},
70 	{"Illegal seek", ESPIPE},
71 	{"Read-only file system", EROFS},
72 	{"Too many links", EMLINK},
73 	{"Broken pipe", EPIPE},
74 	{"Numerical argument out of domain", EDOM},
75 	{"Numerical result out of range", ERANGE},
76 	{"Resource deadlock avoided", EDEADLK},
77 	{"File name too long", ENAMETOOLONG},
78 	{"No locks available", ENOLCK},
79 	{"Function not implemented", ENOSYS},
80 	{"Directory not empty", ENOTEMPTY},
81 	{"Too many levels of symbolic links", ELOOP},
82 	{"No message of desired type", ENOMSG},
83 	{"Identifier removed", EIDRM},
84 	{"No data available", ENODATA},
85 	{"Machine is not on the network", ENONET},
86 	{"Package not installed", ENOPKG},
87 	{"Object is remote", EREMOTE},
88 	{"Link has been severed", ENOLINK},
89 	{"Communication error on send", ECOMM},
90 	{"Protocol error", EPROTO},
91 	{"Bad message", EBADMSG},
92 	{"File descriptor in bad state", EBADFD},
93 	{"Streams pipe error", ESTRPIPE},
94 	{"Too many users", EUSERS},
95 	{"Socket operation on non-socket", ENOTSOCK},
96 	{"Message too long", EMSGSIZE},
97 	{"Protocol not available", ENOPROTOOPT},
98 	{"Protocol not supported", EPROTONOSUPPORT},
99 	{"Socket type not supported", ESOCKTNOSUPPORT},
100 	{"Operation not supported", EOPNOTSUPP},
101 	{"Protocol family not supported", EPFNOSUPPORT},
102 	{"Network is down", ENETDOWN},
103 	{"Network is unreachable", ENETUNREACH},
104 	{"Network dropped connection on reset", ENETRESET},
105 	{"Software caused connection abort", ECONNABORTED},
106 	{"Connection reset by peer", ECONNRESET},
107 	{"No buffer space available", ENOBUFS},
108 	{"Transport endpoint is already connected", EISCONN},
109 	{"Transport endpoint is not connected", ENOTCONN},
110 	{"Cannot send after transport endpoint shutdown", ESHUTDOWN},
111 	{"Connection timed out", ETIMEDOUT},
112 	{"Connection refused", ECONNREFUSED},
113 	{"Host is down", EHOSTDOWN},
114 	{"No route to host", EHOSTUNREACH},
115 	{"Operation already in progress", EALREADY},
116 	{"Operation now in progress", EINPROGRESS},
117 	{"Is a named type file", EISNAM},
118 	{"Remote I/O error", EREMOTEIO},
119 	{"Disk quota exceeded", EDQUOT},
120 /* errors from fossil, vacfs, and u9fs */
121 	{"fid unknown or out of range", EBADF},
122 	{"permission denied", EACCES},
123 	{"file does not exist", ENOENT},
124 	{"authentication failed", ECONNREFUSED},
125 	{"bad offset in directory read", ESPIPE},
126 	{"bad use of fid", EBADF},
127 	{"wstat can't convert between files and directories", EPERM},
128 	{"directory is not empty", ENOTEMPTY},
129 	{"file exists", EEXIST},
130 	{"file already exists", EEXIST},
131 	{"file or directory already exists", EEXIST},
132 	{"fid already in use", EBADF},
133 	{"file in use", ETXTBSY},
134 	{"i/o error", EIO},
135 	{"file already open for I/O", ETXTBSY},
136 	{"illegal mode", EINVAL},
137 	{"illegal name", ENAMETOOLONG},
138 	{"not a directory", ENOTDIR},
139 	{"not a member of proposed group", EPERM},
140 	{"not owner", EACCES},
141 	{"only owner can change group in wstat", EACCES},
142 	{"read only file system", EROFS},
143 	{"no access to special file", EPERM},
144 	{"i/o count too large", EIO},
145 	{"unknown group", EINVAL},
146 	{"unknown user", EINVAL},
147 	{"bogus wstat buffer", EPROTO},
148 	{"exclusive use file already open", EAGAIN},
149 	{"corrupted directory entry", EIO},
150 	{"corrupted file entry", EIO},
151 	{"corrupted block label", EIO},
152 	{"corrupted meta data", EIO},
153 	{"illegal offset", EINVAL},
154 	{"illegal path element", ENOENT},
155 	{"root of file system is corrupted", EIO},
156 	{"corrupted super block", EIO},
157 	{"protocol botch", EPROTO},
158 	{"file system is full", ENOSPC},
159 	{"file is in use", EAGAIN},
160 	{"directory entry is not allocated", ENOENT},
161 	{"file is read only", EROFS},
162 	{"file has been removed", EIDRM},
163 	{"only support truncation to zero length", EPERM},
164 	{"cannot remove root", EPERM},
165 	{"file too big", EFBIG},
166 	{"venti i/o error", EIO},
167 	/* these are not errors */
168 	{"u9fs rhostsauth: no authentication required", 0},
169 	{"u9fs authnone: no authentication required", 0},
170 	{NULL, -1}
171 };
172 
173 /**
174  * p9_error_init - preload mappings into hash list
175  *
176  */
177 
p9_error_init(void)178 int p9_error_init(void)
179 {
180 	struct errormap *c;
181 	int bucket;
182 
183 	/* initialize hash table */
184 	for (bucket = 0; bucket < ERRHASHSZ; bucket++)
185 		INIT_HLIST_HEAD(&hash_errmap[bucket]);
186 
187 	/* load initial error map into hash table */
188 	for (c = errmap; c->name != NULL; c++) {
189 		c->namelen = strlen(c->name);
190 		bucket = jhash(c->name, c->namelen, 0) % ERRHASHSZ;
191 		INIT_HLIST_NODE(&c->list);
192 		hlist_add_head(&c->list, &hash_errmap[bucket]);
193 	}
194 
195 	return 1;
196 }
197 EXPORT_SYMBOL(p9_error_init);
198 
199 /**
200  * errstr2errno - convert error string to error number
201  * @errstr: error string
202  * @len: length of error string
203  *
204  */
205 
p9_errstr2errno(char * errstr,int len)206 int p9_errstr2errno(char *errstr, int len)
207 {
208 	int errno;
209 	struct errormap *c;
210 	int bucket;
211 
212 	errno = 0;
213 	c = NULL;
214 	bucket = jhash(errstr, len, 0) % ERRHASHSZ;
215 	hlist_for_each_entry(c, &hash_errmap[bucket], list) {
216 		if (c->namelen == len && !memcmp(c->name, errstr, len)) {
217 			errno = c->val;
218 			break;
219 		}
220 	}
221 
222 	if (errno == 0) {
223 		/* TODO: if error isn't found, add it dynamically */
224 		errstr[len] = 0;
225 		pr_err("%s: server reported unknown error %s\n",
226 		       __func__, errstr);
227 		errno = ESERVERFAULT;
228 	}
229 
230 	return -errno;
231 }
232 EXPORT_SYMBOL(p9_errstr2errno);
233