net/9p/error.c

0001 // SPDX-License-Identifier: GPL-2.0-only
0002 /*
0003  * Error string handling
0004  *
0005  * Plan 9 uses error strings, Unix uses error numbers.  These functions
0006  * try to help manage that and provide for dynamically adding error
0007  * mappings.
0008  *
0009  *  Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
0010  *  Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
0011  */
0012
0013 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
0014
0015 #include <linux/module.h>
0016 #include <linux/list.h>
0017 #include <linux/jhash.h>
0018 #include <linux/errno.h>
0019 #include <net/9p/9p.h>
0020
0021 /**
0022  * struct errormap - map string errors from Plan 9 to Linux numeric ids
0023  * @name: string sent over 9P
0024  * @val: numeric id most closely representing @name
0025  * @namelen: length of string
0026  * @list: hash-table list for string lookup
0027  */
0028 struct errormap {
0029     char *name;
0030     int val;
0031
0032     int namelen;
0033     struct hlist_node list;
0034 };
0035
0036 #define ERRHASHSZ       32
0037 static struct hlist_head hash_errmap[ERRHASHSZ];
0038
0039 /* FixMe - reduce to a reasonable size */
0040 static struct errormap errmap[] = {
0041     {"Operation not permitted", EPERM},
0042     {"wstat prohibited", EPERM},
0043     {"No such file or directory", ENOENT},
0044     {"directory entry not found", ENOENT},
0045     {"file not found", ENOENT},
0046     {"Interrupted system call", EINTR},
0047     {"Input/output error", EIO},
0048     {"No such device or address", ENXIO},
0049     {"Argument list too long", E2BIG},
0050     {"Bad file descriptor", EBADF},
0051     {"Resource temporarily unavailable", EAGAIN},
0052     {"Cannot allocate memory", ENOMEM},
0053     {"Permission denied", EACCES},
0054     {"Bad address", EFAULT},
0055     {"Block device required", ENOTBLK},
0056     {"Device or resource busy", EBUSY},
0057     {"File exists", EEXIST},
0058     {"Invalid cross-device link", EXDEV},
0059     {"No such device", ENODEV},
0060     {"Not a directory", ENOTDIR},
0061     {"Is a directory", EISDIR},
0062     {"Invalid argument", EINVAL},
0063     {"Too many open files in system", ENFILE},
0064     {"Too many open files", EMFILE},
0065     {"Text file busy", ETXTBSY},
0066     {"File too large", EFBIG},
0067     {"No space left on device", ENOSPC},
0068     {"Illegal seek", ESPIPE},
0069     {"Read-only file system", EROFS},
0070     {"Too many links", EMLINK},
0071     {"Broken pipe", EPIPE},
0072     {"Numerical argument out of domain", EDOM},
0073     {"Numerical result out of range", ERANGE},
0074     {"Resource deadlock avoided", EDEADLK},
0075     {"File name too long", ENAMETOOLONG},
0076     {"No locks available", ENOLCK},
0077     {"Function not implemented", ENOSYS},
0078     {"Directory not empty", ENOTEMPTY},
0079     {"Too many levels of symbolic links", ELOOP},
0080     {"No message of desired type", ENOMSG},
0081     {"Identifier removed", EIDRM},
0082     {"No data available", ENODATA},
0083     {"Machine is not on the network", ENONET},
0084     {"Package not installed", ENOPKG},
0085     {"Object is remote", EREMOTE},
0086     {"Link has been severed", ENOLINK},
0087     {"Communication error on send", ECOMM},
0088     {"Protocol error", EPROTO},
0089     {"Bad message", EBADMSG},
0090     {"File descriptor in bad state", EBADFD},
0091     {"Streams pipe error", ESTRPIPE},
0092     {"Too many users", EUSERS},
0093     {"Socket operation on non-socket", ENOTSOCK},
0094     {"Message too long", EMSGSIZE},
0095     {"Protocol not available", ENOPROTOOPT},
0096     {"Protocol not supported", EPROTONOSUPPORT},
0097     {"Socket type not supported", ESOCKTNOSUPPORT},
0098     {"Operation not supported", EOPNOTSUPP},
0099     {"Protocol family not supported", EPFNOSUPPORT},
0100     {"Network is down", ENETDOWN},
0101     {"Network is unreachable", ENETUNREACH},
0102     {"Network dropped connection on reset", ENETRESET},
0103     {"Software caused connection abort", ECONNABORTED},
0104     {"Connection reset by peer", ECONNRESET},
0105     {"No buffer space available", ENOBUFS},
0106     {"Transport endpoint is already connected", EISCONN},
0107     {"Transport endpoint is not connected", ENOTCONN},
0108     {"Cannot send after transport endpoint shutdown", ESHUTDOWN},
0109     {"Connection timed out", ETIMEDOUT},
0110     {"Connection refused", ECONNREFUSED},
0111     {"Host is down", EHOSTDOWN},
0112     {"No route to host", EHOSTUNREACH},
0113     {"Operation already in progress", EALREADY},
0114     {"Operation now in progress", EINPROGRESS},
0115     {"Is a named type file", EISNAM},
0116     {"Remote I/O error", EREMOTEIO},
0117     {"Disk quota exceeded", EDQUOT},
0118 /* errors from fossil, vacfs, and u9fs */
0119     {"fid unknown or out of range", EBADF},
0120     {"permission denied", EACCES},
0121     {"file does not exist", ENOENT},
0122     {"authentication failed", ECONNREFUSED},
0123     {"bad offset in directory read", ESPIPE},
0124     {"bad use of fid", EBADF},
0125     {"wstat can't convert between files and directories", EPERM},
0126     {"directory is not empty", ENOTEMPTY},
0127     {"file exists", EEXIST},
0128     {"file already exists", EEXIST},
0129     {"file or directory already exists", EEXIST},
0130     {"fid already in use", EBADF},
0131     {"file in use", ETXTBSY},
0132     {"i/o error", EIO},
0133     {"file already open for I/O", ETXTBSY},
0134     {"illegal mode", EINVAL},
0135     {"illegal name", ENAMETOOLONG},
0136     {"not a directory", ENOTDIR},
0137     {"not a member of proposed group", EPERM},
0138     {"not owner", EACCES},
0139     {"only owner can change group in wstat", EACCES},
0140     {"read only file system", EROFS},
0141     {"no access to special file", EPERM},
0142     {"i/o count too large", EIO},
0143     {"unknown group", EINVAL},
0144     {"unknown user", EINVAL},
0145     {"bogus wstat buffer", EPROTO},
0146     {"exclusive use file already open", EAGAIN},
0147     {"corrupted directory entry", EIO},
0148     {"corrupted file entry", EIO},
0149     {"corrupted block label", EIO},
0150     {"corrupted meta data", EIO},
0151     {"illegal offset", EINVAL},
0152     {"illegal path element", ENOENT},
0153     {"root of file system is corrupted", EIO},
0154     {"corrupted super block", EIO},
0155     {"protocol botch", EPROTO},
0156     {"file system is full", ENOSPC},
0157     {"file is in use", EAGAIN},
0158     {"directory entry is not allocated", ENOENT},
0159     {"file is read only", EROFS},
0160     {"file has been removed", EIDRM},
0161     {"only support truncation to zero length", EPERM},
0162     {"cannot remove root", EPERM},
0163     {"file too big", EFBIG},
0164     {"venti i/o error", EIO},
0165     /* these are not errors */
0166     {"u9fs rhostsauth: no authentication required", 0},
0167     {"u9fs authnone: no authentication required", 0},
0168     {NULL, -1}
0169 };
0170
0171 /**
0172  * p9_error_init - preload mappings into hash list
0173  *
0174  */
0175
0176 int p9_error_init(void)
0177 {
0178     struct errormap *c;
0179     int bucket;
0180
0181     /* initialize hash table */
0182     for (bucket = 0; bucket < ERRHASHSZ; bucket++)
0183         INIT_HLIST_HEAD(&hash_errmap[bucket]);
0184
0185     /* load initial error map into hash table */
0186     for (c = errmap; c->name; c++) {
0187         c->namelen = strlen(c->name);
0188         bucket = jhash(c->name, c->namelen, 0) % ERRHASHSZ;
0189         INIT_HLIST_NODE(&c->list);
0190         hlist_add_head(&c->list, &hash_errmap[bucket]);
0191     }
0192
0193     return 1;
0194 }
0195 EXPORT_SYMBOL(p9_error_init);
0196
0197 /**
0198  * p9_errstr2errno - convert error string to error number
0199  * @errstr: error string
0200  * @len: length of error string
0201  *
0202  */
0203
0204 int p9_errstr2errno(char *errstr, int len)
0205 {
0206     int errno;
0207     struct errormap *c;
0208     int bucket;
0209
0210     errno = 0;
0211     c = NULL;
0212     bucket = jhash(errstr, len, 0) % ERRHASHSZ;
0213     hlist_for_each_entry(c, &hash_errmap[bucket], list) {
0214         if (c->namelen == len && !memcmp(c->name, errstr, len)) {
0215             errno = c->val;
0216             break;
0217         }
0218     }
0219
0220     if (errno == 0) {
0221         /* TODO: if error isn't found, add it dynamically */
0222         errstr[len] = 0;
0223         pr_err("%s: server reported unknown error %s\n",
0224                __func__, errstr);
0225         errno = ESERVERFAULT;
0226     }
0227
0228     return -errno;
0229 }
0230 EXPORT_SYMBOL(p9_errstr2errno);