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/types.h> 30 #include <sys/systm.h> 31 #include <sys/param.h> 32 #include <sys/sbuf.h> 33 #include <sys/syslog.h> 34 #include <sys/vnode.h> 35 36 #include <linux/seq_file.h> 37 #include <linux/file.h> 38 39 #undef file 40 MALLOC_DEFINE(M_LSEQ, "seq_file", "seq_file"); 41 42 ssize_t 43 seq_read(struct linux_file *f, char *ubuf, size_t size, off_t *ppos) 44 { 45 struct seq_file *m; 46 struct sbuf *sbuf; 47 void *p; 48 ssize_t rc; 49 50 m = f->private_data; 51 sbuf = m->buf; 52 53 p = m->op->start(m, ppos); 54 rc = m->op->show(m, p); 55 if (rc) 56 return (rc); 57 58 rc = sbuf_finish(sbuf); 59 if (rc) 60 return (rc); 61 62 rc = sbuf_len(sbuf); 63 if (*ppos >= rc || size < 1) 64 return (-EINVAL); 65 66 size = min(rc - *ppos, size); 67 memcpy(ubuf, sbuf_data(sbuf) + *ppos, size); 68 *ppos += size; 69 70 return (size); 71 } 72 73 int 74 seq_write(struct seq_file *seq, const void *data, size_t len) 75 { 76 int ret; 77 78 ret = sbuf_bcpy(seq->buf, data, len); 79 if (ret == 0) 80 seq->size = sbuf_len(seq->buf); 81 82 return (ret); 83 } 84 85 void 86 seq_putc(struct seq_file *seq, char c) 87 { 88 int ret; 89 90 ret = sbuf_putc(seq->buf, c); 91 if (ret == 0) 92 seq->size = sbuf_len(seq->buf); 93 } 94 95 void 96 seq_puts(struct seq_file *seq, const char *str) 97 { 98 int ret; 99 100 ret = sbuf_printf(seq->buf, "%s", str); 101 if (ret == 0) 102 seq->size = sbuf_len(seq->buf); 103 } 104 105 /* 106 * This only needs to be a valid address for lkpi 107 * drivers it should never actually be called 108 */ 109 off_t 110 seq_lseek(struct linux_file *file, off_t offset, int whence) 111 { 112 113 panic("%s not supported\n", __FUNCTION__); 114 return (0); 115 } 116 117 static void * 118 single_start(struct seq_file *p, off_t *pos) 119 { 120 121 return ((void *)(uintptr_t)(*pos == 0)); 122 } 123 124 static void * 125 single_next(struct seq_file *p, void *v, off_t *pos) 126 { 127 128 ++*pos; 129 return (NULL); 130 } 131 132 static void 133 single_stop(struct seq_file *p, void *v) 134 { 135 } 136 137 static int 138 _seq_open_without_sbuf(struct linux_file *f, const struct seq_operations *op) 139 { 140 struct seq_file *p; 141 142 if ((p = malloc(sizeof(*p), M_LSEQ, M_NOWAIT|M_ZERO)) == NULL) 143 return (-ENOMEM); 144 145 p->file = f; 146 p->op = op; 147 f->private_data = (void *) p; 148 return (0); 149 } 150 151 int 152 seq_open(struct linux_file *f, const struct seq_operations *op) 153 { 154 int ret; 155 156 ret = _seq_open_without_sbuf(f, op); 157 if (ret == 0) 158 ((struct seq_file *)f->private_data)->buf = sbuf_new_auto(); 159 160 return (ret); 161 } 162 163 void * 164 __seq_open_private(struct linux_file *f, const struct seq_operations *op, int size) 165 { 166 struct seq_file *seq_file; 167 void *private; 168 int error; 169 170 private = malloc(size, M_LSEQ, M_NOWAIT|M_ZERO); 171 if (private == NULL) 172 return (NULL); 173 174 error = seq_open(f, op); 175 if (error < 0) { 176 free(private, M_LSEQ); 177 return (NULL); 178 } 179 180 seq_file = (struct seq_file *)f->private_data; 181 seq_file->private = private; 182 183 return (private); 184 } 185 186 static int 187 _single_open_without_sbuf(struct linux_file *f, int (*show)(struct seq_file *, void *), void *d) 188 { 189 struct seq_operations *op; 190 int rc = -ENOMEM; 191 192 op = malloc(sizeof(*op), M_LSEQ, M_NOWAIT); 193 if (op) { 194 op->start = single_start; 195 op->next = single_next; 196 op->stop = single_stop; 197 op->show = show; 198 rc = _seq_open_without_sbuf(f, op); 199 if (rc) 200 free(op, M_LSEQ); 201 else 202 ((struct seq_file *)f->private_data)->private = d; 203 } 204 return (rc); 205 } 206 207 int 208 single_open(struct linux_file *f, int (*show)(struct seq_file *, void *), void *d) 209 { 210 int ret; 211 212 ret = _single_open_without_sbuf(f, show, d); 213 if (ret == 0) 214 ((struct seq_file *)f->private_data)->buf = sbuf_new_auto(); 215 216 return (ret); 217 } 218 219 int 220 single_open_size(struct linux_file *f, int (*show)(struct seq_file *, void *), void *d, size_t size) 221 { 222 int ret; 223 224 ret = _single_open_without_sbuf(f, show, d); 225 if (ret == 0) 226 ((struct seq_file *)f->private_data)->buf = sbuf_new( 227 NULL, NULL, size, SBUF_AUTOEXTEND); 228 229 return (ret); 230 } 231 232 int 233 seq_release(struct inode *inode __unused, struct linux_file *file) 234 { 235 struct seq_file *m; 236 struct sbuf *s; 237 238 m = file->private_data; 239 s = m->buf; 240 241 sbuf_delete(s); 242 free(m, M_LSEQ); 243 244 return (0); 245 } 246 247 int 248 seq_release_private(struct inode *inode __unused, struct linux_file *f) 249 { 250 struct seq_file *seq; 251 252 seq = (struct seq_file *)f->private_data; 253 free(seq->private, M_LSEQ); 254 return (seq_release(inode, f)); 255 } 256 257 int 258 single_release(struct vnode *v, struct linux_file *f) 259 { 260 const struct seq_operations *op; 261 struct seq_file *m; 262 int rc; 263 264 /* be NULL safe */ 265 if ((m = f->private_data) == NULL) 266 return (0); 267 268 op = m->op; 269 rc = seq_release(v, f); 270 free(__DECONST(void *, op), M_LSEQ); 271 return (rc); 272 } 273 274 void 275 lkpi_seq_vprintf(struct seq_file *m, const char *fmt, va_list args) 276 { 277 int ret; 278 279 ret = sbuf_vprintf(m->buf, fmt, args); 280 if (ret == 0) 281 m->size = sbuf_len(m->buf); 282 } 283 284 void 285 lkpi_seq_printf(struct seq_file *m, const char *fmt, ...) 286 { 287 va_list args; 288 289 va_start(args, fmt); 290 lkpi_seq_vprintf(m, fmt, args); 291 va_end(args); 292 } 293 294 bool 295 seq_has_overflowed(struct seq_file *m) 296 { 297 return (sbuf_len(m->buf) == -1); 298 } 299