1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause 3 * 4 * Copyright (c) 2016-2018, Matthew Macy <mmacy@freebsd.org> 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 18 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 25 * SUCH DAMAGE. 26 * 27 */ 28 29 #include <sys/cdefs.h> 30 #include <sys/types.h> 31 #include <sys/systm.h> 32 #include <sys/param.h> 33 #include <sys/sbuf.h> 34 #include <sys/syslog.h> 35 #include <sys/vnode.h> 36 37 #include <linux/seq_file.h> 38 #include <linux/file.h> 39 40 #undef file 41 MALLOC_DEFINE(M_LSEQ, "seq_file", "seq_file"); 42 43 ssize_t 44 seq_read(struct linux_file *f, char *ubuf, size_t size, off_t *ppos) 45 { 46 struct seq_file *m; 47 struct sbuf *sbuf; 48 void *p; 49 ssize_t rc; 50 51 m = f->private_data; 52 sbuf = m->buf; 53 54 p = m->op->start(m, ppos); 55 rc = m->op->show(m, p); 56 if (rc) 57 return (rc); 58 59 rc = sbuf_finish(sbuf); 60 if (rc) 61 return (rc); 62 63 rc = sbuf_len(sbuf); 64 if (*ppos >= rc || size < 1) 65 return (-EINVAL); 66 67 size = min(rc - *ppos, size); 68 rc = strscpy(ubuf, sbuf_data(sbuf) + *ppos, size + 1); 69 70 /* add 1 for null terminator */ 71 if (rc > 0) 72 rc += 1; 73 74 return (rc); 75 } 76 77 int 78 seq_write(struct seq_file *seq, const void *data, size_t len) 79 { 80 int ret; 81 82 ret = sbuf_bcpy(seq->buf, data, len); 83 if (ret == 0) 84 seq->size = sbuf_len(seq->buf); 85 86 return (ret); 87 } 88 89 void 90 seq_putc(struct seq_file *seq, char c) 91 { 92 int ret; 93 94 ret = sbuf_putc(seq->buf, c); 95 if (ret == 0) 96 seq->size = sbuf_len(seq->buf); 97 } 98 99 void 100 seq_puts(struct seq_file *seq, const char *str) 101 { 102 int ret; 103 104 ret = sbuf_printf(seq->buf, "%s", str); 105 if (ret == 0) 106 seq->size = sbuf_len(seq->buf); 107 } 108 109 /* 110 * This only needs to be a valid address for lkpi 111 * drivers it should never actually be called 112 */ 113 off_t 114 seq_lseek(struct linux_file *file, off_t offset, int whence) 115 { 116 117 panic("%s not supported\n", __FUNCTION__); 118 return (0); 119 } 120 121 static void * 122 single_start(struct seq_file *p, off_t *pos) 123 { 124 125 return ((void *)(uintptr_t)(*pos == 0)); 126 } 127 128 static void * 129 single_next(struct seq_file *p, void *v, off_t *pos) 130 { 131 132 ++*pos; 133 return (NULL); 134 } 135 136 static void 137 single_stop(struct seq_file *p, void *v) 138 { 139 } 140 141 static int 142 _seq_open_without_sbuf(struct linux_file *f, const struct seq_operations *op) 143 { 144 struct seq_file *p; 145 146 if ((p = malloc(sizeof(*p), M_LSEQ, M_NOWAIT|M_ZERO)) == NULL) 147 return (-ENOMEM); 148 149 p->file = f; 150 p->op = op; 151 f->private_data = (void *) p; 152 return (0); 153 } 154 155 int 156 seq_open(struct linux_file *f, const struct seq_operations *op) 157 { 158 int ret; 159 160 ret = _seq_open_without_sbuf(f, op); 161 if (ret == 0) 162 ((struct seq_file *)f->private_data)->buf = sbuf_new_auto(); 163 164 return (ret); 165 } 166 167 void * 168 __seq_open_private(struct linux_file *f, const struct seq_operations *op, int size) 169 { 170 struct seq_file *seq_file; 171 void *private; 172 int error; 173 174 private = malloc(size, M_LSEQ, M_NOWAIT|M_ZERO); 175 if (private == NULL) 176 return (NULL); 177 178 error = seq_open(f, op); 179 if (error < 0) { 180 free(private, M_LSEQ); 181 return (NULL); 182 } 183 184 seq_file = (struct seq_file *)f->private_data; 185 seq_file->private = private; 186 187 return (private); 188 } 189 190 static int 191 _single_open_without_sbuf(struct linux_file *f, int (*show)(struct seq_file *, void *), void *d) 192 { 193 struct seq_operations *op; 194 int rc = -ENOMEM; 195 196 op = malloc(sizeof(*op), M_LSEQ, M_NOWAIT); 197 if (op) { 198 op->start = single_start; 199 op->next = single_next; 200 op->stop = single_stop; 201 op->show = show; 202 rc = _seq_open_without_sbuf(f, op); 203 if (rc) 204 free(op, M_LSEQ); 205 else 206 ((struct seq_file *)f->private_data)->private = d; 207 } 208 return (rc); 209 } 210 211 int 212 single_open(struct linux_file *f, int (*show)(struct seq_file *, void *), void *d) 213 { 214 int ret; 215 216 ret = _single_open_without_sbuf(f, show, d); 217 if (ret == 0) 218 ((struct seq_file *)f->private_data)->buf = sbuf_new_auto(); 219 220 return (ret); 221 } 222 223 int 224 single_open_size(struct linux_file *f, int (*show)(struct seq_file *, void *), void *d, size_t size) 225 { 226 int ret; 227 228 ret = _single_open_without_sbuf(f, show, d); 229 if (ret == 0) 230 ((struct seq_file *)f->private_data)->buf = sbuf_new( 231 NULL, NULL, size, SBUF_AUTOEXTEND); 232 233 return (ret); 234 } 235 236 int 237 seq_release(struct inode *inode __unused, struct linux_file *file) 238 { 239 struct seq_file *m; 240 struct sbuf *s; 241 242 m = file->private_data; 243 s = m->buf; 244 245 sbuf_delete(s); 246 free(m, M_LSEQ); 247 248 return (0); 249 } 250 251 int 252 seq_release_private(struct inode *inode __unused, struct linux_file *f) 253 { 254 struct seq_file *seq; 255 256 seq = (struct seq_file *)f->private_data; 257 free(seq->private, M_LSEQ); 258 return (seq_release(inode, f)); 259 } 260 261 int 262 single_release(struct vnode *v, struct linux_file *f) 263 { 264 const struct seq_operations *op; 265 struct seq_file *m; 266 int rc; 267 268 /* be NULL safe */ 269 if ((m = f->private_data) == NULL) 270 return (0); 271 272 op = m->op; 273 rc = seq_release(v, f); 274 free(__DECONST(void *, op), M_LSEQ); 275 return (rc); 276 } 277 278 void 279 lkpi_seq_vprintf(struct seq_file *m, const char *fmt, va_list args) 280 { 281 int ret; 282 283 ret = sbuf_vprintf(m->buf, fmt, args); 284 if (ret == 0) 285 m->size = sbuf_len(m->buf); 286 } 287 288 void 289 lkpi_seq_printf(struct seq_file *m, const char *fmt, ...) 290 { 291 va_list args; 292 293 va_start(args, fmt); 294 lkpi_seq_vprintf(m, fmt, args); 295 va_end(args); 296 } 297 298 bool 299 seq_has_overflowed(struct seq_file *m) 300 { 301 return (sbuf_len(m->buf) == -1); 302 } 303