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