1/* 2 Unix SMB/CIFS implementation. 3 IRIX kernel oplock processing 4 Copyright (C) Andrew Tridgell 1992-1998 5 6 This program is free software; you can redistribute it and/or modify 7 it under the terms of the GNU General Public License as published by 8 the Free Software Foundation; either version 3 of the License, or 9 (at your option) any later version. 10 11 This program is distributed in the hope that it will be useful, 12 but WITHOUT ANY WARRANTY; without even the implied warranty of 13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 GNU General Public License for more details. 15 16 You should have received a copy of the GNU General Public License 17 along with this program. If not, see <http://www.gnu.org/licenses/>. 18*/ 19 20#define DBGC_CLASS DBGC_LOCKING 21#include "includes.h" 22#include "smbd/globals.h" 23 24#if HAVE_KERNEL_OPLOCKS_IRIX 25 26struct irix_oplocks_context { 27 struct kernel_oplocks *ctx; 28 int write_fd; 29 int read_fd; 30 struct fd_event *read_fde; 31 bool pending; 32}; 33 34/**************************************************************************** 35 Test to see if IRIX kernel oplocks work. 36****************************************************************************/ 37 38static bool irix_oplocks_available(void) 39{ 40 int fd; 41 int pfd[2]; 42 TALLOC_CTX *ctx = talloc_stackframe(); 43 char *tmpname = NULL; 44 45 set_effective_capability(KERNEL_OPLOCK_CAPABILITY); 46 47 tmpname = talloc_asprintf(ctx, 48 "%s/koplock.%d", 49 lp_lockdir(), 50 (int)sys_getpid()); 51 if (!tmpname) { 52 TALLOC_FREE(ctx); 53 return False; 54 } 55 56 if(pipe(pfd) != 0) { 57 DEBUG(0,("check_kernel_oplocks: Unable to create pipe. Error " 58 "was %s\n", 59 strerror(errno) )); 60 TALLOC_FREE(ctx); 61 return False; 62 } 63 64 if((fd = sys_open(tmpname, O_RDWR|O_CREAT|O_EXCL|O_TRUNC, 0600)) < 0) { 65 DEBUG(0,("check_kernel_oplocks: Unable to open temp test file " 66 "%s. Error was %s\n", 67 tmpname, strerror(errno) )); 68 unlink( tmpname ); 69 close(pfd[0]); 70 close(pfd[1]); 71 TALLOC_FREE(ctx); 72 return False; 73 } 74 75 unlink(tmpname); 76 77 TALLOC_FREE(ctx); 78 79 if(sys_fcntl_long(fd, F_OPLKREG, pfd[1]) == -1) { 80 DEBUG(0,("check_kernel_oplocks: Kernel oplocks are not " 81 "available on this machine. Disabling kernel oplock " 82 "support.\n" )); 83 close(pfd[0]); 84 close(pfd[1]); 85 close(fd); 86 return False; 87 } 88 89 if(sys_fcntl_long(fd, F_OPLKACK, OP_REVOKE) < 0 ) { 90 DEBUG(0,("check_kernel_oplocks: Error when removing kernel " 91 "oplock. Error was %s. Disabling kernel oplock " 92 "support.\n", strerror(errno) )); 93 close(pfd[0]); 94 close(pfd[1]); 95 close(fd); 96 return False; 97 } 98 99 close(pfd[0]); 100 close(pfd[1]); 101 close(fd); 102 103 return True; 104} 105 106/* 107 * This is bad because the file_id should always be created through the vfs 108 * layer! Unfortunately, a conn struct isn't available here. 109 */ 110static struct file_id file_id_create_dev(SMB_DEV_T dev, SMB_INO_T inode) 111{ 112 struct file_id key; 113 114 /* the ZERO_STRUCT ensures padding doesn't break using the key as a 115 * blob */ 116 ZERO_STRUCT(key); 117 118 key.devid = dev; 119 key.inode = inode; 120 121 return key; 122} 123 124/**************************************************************************** 125 * Deal with the IRIX kernel <--> smbd 126 * oplock break protocol. 127****************************************************************************/ 128 129static files_struct *irix_oplock_receive_message(struct kernel_oplocks *_ctx) 130{ 131 struct irix_oplocks_context *ctx = talloc_get_type(_ctx->private_data, 132 struct irix_oplocks_context); 133 oplock_stat_t os; 134 char dummy; 135 struct file_id fileid; 136 files_struct *fsp; 137 138 /* 139 * TODO: is it correct to assume we only get one 140 * oplock break, for each byte we read from the pipe? 141 */ 142 ctx->pending = false; 143 144 /* 145 * Read one byte of zero to clear the 146 * kernel break notify message. 147 */ 148 149 if(read(ctx->read_fd, &dummy, 1) != 1) { 150 DEBUG(0,("irix_oplock_receive_message: read of kernel " 151 "notification failed. Error was %s.\n", 152 strerror(errno) )); 153 return NULL; 154 } 155 156 /* 157 * Do a query to get the 158 * device and inode of the file that has the break 159 * request outstanding. 160 */ 161 162 if(sys_fcntl_ptr(ctx->read_fd, F_OPLKSTAT, &os) < 0) { 163 DEBUG(0,("irix_oplock_receive_message: fcntl of kernel " 164 "notification failed. Error was %s.\n", 165 strerror(errno) )); 166 if(errno == EAGAIN) { 167 /* 168 * Duplicate kernel break message - ignore. 169 */ 170 return NULL; 171 } 172 return NULL; 173 } 174 175 /* 176 * We only have device and inode info here - we have to guess that this 177 * is the first fsp open with this dev,ino pair. 178 * 179 * NOTE: this doesn't work if any VFS modules overloads 180 * the file_id_create() hook! 181 */ 182 183 fileid = file_id_create_dev((SMB_DEV_T)os.os_dev, 184 (SMB_INO_T)os.os_ino); 185 if ((fsp = file_find_di_first(fileid)) == NULL) { 186 DEBUG(0,("irix_oplock_receive_message: unable to find open " 187 "file with dev = %x, inode = %.0f\n", 188 (unsigned int)os.os_dev, (double)os.os_ino )); 189 return NULL; 190 } 191 192 DEBUG(5,("irix_oplock_receive_message: kernel oplock break request " 193 "received for file_id %s gen_id = %ul", 194 file_id_string_tos(&fsp->file_id), 195 fsp->fh->gen_id )); 196 197 return fsp; 198} 199 200/**************************************************************************** 201 Attempt to set an kernel oplock on a file. 202****************************************************************************/ 203 204static bool irix_set_kernel_oplock(struct kernel_oplocks *_ctx, 205 files_struct *fsp, int oplock_type) 206{ 207 struct irix_oplocks_context *ctx = talloc_get_type(_ctx->private_data, 208 struct irix_oplocks_context); 209 210 if (sys_fcntl_long(fsp->fh->fd, F_OPLKREG, ctx->write_fd) == -1) { 211 if(errno != EAGAIN) { 212 DEBUG(0,("irix_set_kernel_oplock: Unable to get " 213 "kernel oplock on file %s, file_id %s " 214 "gen_id = %ul. Error was %s\n", 215 fsp_str_dbg(fsp), 216 file_id_string_tos(&fsp->file_id), 217 fsp->fh->gen_id, 218 strerror(errno) )); 219 } else { 220 DEBUG(5,("irix_set_kernel_oplock: Refused oplock on " 221 "file %s, fd = %d, file_id = %s, " 222 "gen_id = %ul. Another process had the file " 223 "open.\n", 224 fsp_str_dbg(fsp), fsp->fh->fd, 225 file_id_string_tos(&fsp->file_id), 226 fsp->fh->gen_id )); 227 } 228 return False; 229 } 230 231 DEBUG(10,("irix_set_kernel_oplock: got kernel oplock on file %s, file_id = %s " 232 "gen_id = %ul\n", 233 fsp_str_dbg(fsp), file_id_string_tos(&fsp->file_id), 234 fsp->fh->gen_id)); 235 236 return True; 237} 238 239/**************************************************************************** 240 Release a kernel oplock on a file. 241****************************************************************************/ 242 243static void irix_release_kernel_oplock(struct kernel_oplocks *_ctx, 244 files_struct *fsp, int oplock_type) 245{ 246 if (DEBUGLVL(10)) { 247 /* 248 * Check and print out the current kernel 249 * oplock state of this file. 250 */ 251 int state = sys_fcntl_long(fsp->fh->fd, F_OPLKACK, -1); 252 dbgtext("irix_release_kernel_oplock: file %s, file_id = %s" 253 "gen_id = %ul, has kernel oplock state " 254 "of %x.\n", fsp_str_dbg(fsp), 255 file_id_string_tos(&fsp->file_id), 256 fsp->fh->gen_id, state ); 257 } 258 259 /* 260 * Remove the kernel oplock on this file. 261 */ 262 if(sys_fcntl_long(fsp->fh->fd, F_OPLKACK, OP_REVOKE) < 0) { 263 if( DEBUGLVL( 0 )) { 264 dbgtext("irix_release_kernel_oplock: Error when " 265 "removing kernel oplock on file " ); 266 dbgtext("%s, file_id = %s gen_id = %ul. " 267 "Error was %s\n", 268 fsp_str_dbg(fsp), 269 file_id_string_tos(&fsp->file_id), 270 fsp->fh->gen_id, 271 strerror(errno) ); 272 } 273 } 274} 275 276static void irix_oplocks_read_fde_handler(struct event_context *ev, 277 struct fd_event *fde, 278 uint16_t flags, 279 void *private_data) 280{ 281 struct irix_oplocks_context *ctx = talloc_get_type(private_data, 282 struct irix_oplocks_context); 283 files_struct *fsp; 284 285 fsp = irix_oplock_receive_message(ctx->ctx); 286 break_kernel_oplock(smbd_messaging_context(), fsp); 287} 288 289/**************************************************************************** 290 Setup kernel oplocks. 291****************************************************************************/ 292 293static const struct kernel_oplocks_ops irix_koplocks = { 294 .set_oplock = irix_set_kernel_oplock, 295 .release_oplock = irix_release_kernel_oplock, 296 .contend_level2_oplocks_begin = NULL, 297 .contend_level2_oplocks_end = NULL, 298}; 299 300struct kernel_oplocks *irix_init_kernel_oplocks(TALLOC_CTX *mem_ctx) 301{ 302 struct kernel_oplocks *_ctx; 303 struct irix_oplocks_context *ctx; 304 int pfd[2]; 305 306 if (!irix_oplocks_available()) 307 return NULL; 308 309 _ctx = talloc_zero(mem_ctx, struct kernel_oplocks); 310 if (!_ctx) { 311 return NULL; 312 } 313 314 ctx = talloc_zero(_ctx, struct irix_oplocks_context); 315 if (!ctx) { 316 talloc_free(_ctx); 317 return NULL; 318 } 319 _ctx->ops = &irix_koplocks; 320 _ctx->private_data = ctx; 321 ctx->ctx = _ctx; 322 323 if(pipe(pfd) != 0) { 324 talloc_free(_ctx); 325 DEBUG(0,("setup_kernel_oplock_pipe: Unable to create pipe. " 326 "Error was %s\n", strerror(errno) )); 327 return False; 328 } 329 330 ctx->read_fd = pfd[0]; 331 ctx->write_fd = pfd[1]; 332 333 ctx->read_fde = event_add_fd(smbd_event_context(), 334 ctx, 335 ctx->read_fd, 336 EVENT_FD_READ, 337 irix_oplocks_read_fde_handler, 338 ctx); 339 return _ctx; 340} 341#else 342 void oplock_irix_dummy(void); 343 void oplock_irix_dummy(void) {} 344#endif /* HAVE_KERNEL_OPLOCKS_IRIX */ 345