1 /* 2 * Copyright 2016-17 IBM Corp. 3 * 4 * This program is free software; you can redistribute it and/or 5 * modify it under the terms of the GNU General Public License 6 * as published by the Free Software Foundation; either version 7 * 2 of the License, or (at your option) any later version. 8 */ 9 10 #define pr_fmt(fmt) "vas: " fmt 11 12 #include <linux/types.h> 13 #include <linux/mutex.h> 14 #include <linux/slab.h> 15 #include <linux/io.h> 16 #include <linux/log2.h> 17 #include <linux/rcupdate.h> 18 #include <linux/cred.h> 19 #include <asm/switch_to.h> 20 #include <asm/ppc-opcode.h> 21 #include "vas.h" 22 #include "copy-paste.h" 23 24 #define CREATE_TRACE_POINTS 25 #include "vas-trace.h" 26 27 /* 28 * Compute the paste address region for the window @window using the 29 * ->paste_base_addr and ->paste_win_id_shift we got from device tree. 30 */ 31 static void compute_paste_address(struct vas_window *window, u64 *addr, int *len) 32 { 33 int winid; 34 u64 base, shift; 35 36 base = window->vinst->paste_base_addr; 37 shift = window->vinst->paste_win_id_shift; 38 winid = window->winid; 39 40 *addr = base + (winid << shift); 41 if (len) 42 *len = PAGE_SIZE; 43 44 pr_debug("Txwin #%d: Paste addr 0x%llx\n", winid, *addr); 45 } 46 47 u64 vas_win_paste_addr(struct vas_window *win) 48 { 49 u64 addr; 50 51 compute_paste_address(win, &addr, NULL); 52 53 return addr; 54 } 55 EXPORT_SYMBOL(vas_win_paste_addr); 56 57 static inline void get_hvwc_mmio_bar(struct vas_window *window, 58 u64 *start, int *len) 59 { 60 u64 pbaddr; 61 62 pbaddr = window->vinst->hvwc_bar_start; 63 *start = pbaddr + window->winid * VAS_HVWC_SIZE; 64 *len = VAS_HVWC_SIZE; 65 } 66 67 static inline void get_uwc_mmio_bar(struct vas_window *window, 68 u64 *start, int *len) 69 { 70 u64 pbaddr; 71 72 pbaddr = window->vinst->uwc_bar_start; 73 *start = pbaddr + window->winid * VAS_UWC_SIZE; 74 *len = VAS_UWC_SIZE; 75 } 76 77 /* 78 * Map the paste bus address of the given send window into kernel address 79 * space. Unlike MMIO regions (map_mmio_region() below), paste region must 80 * be mapped cache-able and is only applicable to send windows. 81 */ 82 static void *map_paste_region(struct vas_window *txwin) 83 { 84 int len; 85 void *map; 86 char *name; 87 u64 start; 88 89 name = kasprintf(GFP_KERNEL, "window-v%d-w%d", txwin->vinst->vas_id, 90 txwin->winid); 91 if (!name) 92 goto free_name; 93 94 txwin->paste_addr_name = name; 95 compute_paste_address(txwin, &start, &len); 96 97 if (!request_mem_region(start, len, name)) { 98 pr_devel("%s(): request_mem_region(0x%llx, %d) failed\n", 99 __func__, start, len); 100 goto free_name; 101 } 102 103 map = ioremap_cache(start, len); 104 if (!map) { 105 pr_devel("%s(): ioremap_cache(0x%llx, %d) failed\n", __func__, 106 start, len); 107 goto free_name; 108 } 109 110 pr_devel("Mapped paste addr 0x%llx to kaddr 0x%p\n", start, map); 111 return map; 112 113 free_name: 114 kfree(name); 115 return ERR_PTR(-ENOMEM); 116 } 117 118 static void *map_mmio_region(char *name, u64 start, int len) 119 { 120 void *map; 121 122 if (!request_mem_region(start, len, name)) { 123 pr_devel("%s(): request_mem_region(0x%llx, %d) failed\n", 124 __func__, start, len); 125 return NULL; 126 } 127 128 map = ioremap(start, len); 129 if (!map) { 130 pr_devel("%s(): ioremap(0x%llx, %d) failed\n", __func__, start, 131 len); 132 return NULL; 133 } 134 135 return map; 136 } 137 138 static void unmap_region(void *addr, u64 start, int len) 139 { 140 iounmap(addr); 141 release_mem_region((phys_addr_t)start, len); 142 } 143 144 /* 145 * Unmap the paste address region for a window. 146 */ 147 static void unmap_paste_region(struct vas_window *window) 148 { 149 int len; 150 u64 busaddr_start; 151 152 if (window->paste_kaddr) { 153 compute_paste_address(window, &busaddr_start, &len); 154 unmap_region(window->paste_kaddr, busaddr_start, len); 155 window->paste_kaddr = NULL; 156 kfree(window->paste_addr_name); 157 window->paste_addr_name = NULL; 158 } 159 } 160 161 /* 162 * Unmap the MMIO regions for a window. Hold the vas_mutex so we don't 163 * unmap when the window's debugfs dir is in use. This serializes close 164 * of a window even on another VAS instance but since its not a critical 165 * path, just minimize the time we hold the mutex for now. We can add 166 * a per-instance mutex later if necessary. 167 */ 168 static void unmap_winctx_mmio_bars(struct vas_window *window) 169 { 170 int len; 171 void *uwc_map; 172 void *hvwc_map; 173 u64 busaddr_start; 174 175 mutex_lock(&vas_mutex); 176 177 hvwc_map = window->hvwc_map; 178 window->hvwc_map = NULL; 179 180 uwc_map = window->uwc_map; 181 window->uwc_map = NULL; 182 183 mutex_unlock(&vas_mutex); 184 185 if (hvwc_map) { 186 get_hvwc_mmio_bar(window, &busaddr_start, &len); 187 unmap_region(hvwc_map, busaddr_start, len); 188 } 189 190 if (uwc_map) { 191 get_uwc_mmio_bar(window, &busaddr_start, &len); 192 unmap_region(uwc_map, busaddr_start, len); 193 } 194 } 195 196 /* 197 * Find the Hypervisor Window Context (HVWC) MMIO Base Address Region and the 198 * OS/User Window Context (UWC) MMIO Base Address Region for the given window. 199 * Map these bus addresses and save the mapped kernel addresses in @window. 200 */ 201 int map_winctx_mmio_bars(struct vas_window *window) 202 { 203 int len; 204 u64 start; 205 206 get_hvwc_mmio_bar(window, &start, &len); 207 window->hvwc_map = map_mmio_region("HVWCM_Window", start, len); 208 209 get_uwc_mmio_bar(window, &start, &len); 210 window->uwc_map = map_mmio_region("UWCM_Window", start, len); 211 212 if (!window->hvwc_map || !window->uwc_map) { 213 unmap_winctx_mmio_bars(window); 214 return -1; 215 } 216 217 return 0; 218 } 219 220 /* 221 * Reset all valid registers in the HV and OS/User Window Contexts for 222 * the window identified by @window. 223 * 224 * NOTE: We cannot really use a for loop to reset window context. Not all 225 * offsets in a window context are valid registers and the valid 226 * registers are not sequential. And, we can only write to offsets 227 * with valid registers. 228 */ 229 void reset_window_regs(struct vas_window *window) 230 { 231 write_hvwc_reg(window, VREG(LPID), 0ULL); 232 write_hvwc_reg(window, VREG(PID), 0ULL); 233 write_hvwc_reg(window, VREG(XLATE_MSR), 0ULL); 234 write_hvwc_reg(window, VREG(XLATE_LPCR), 0ULL); 235 write_hvwc_reg(window, VREG(XLATE_CTL), 0ULL); 236 write_hvwc_reg(window, VREG(AMR), 0ULL); 237 write_hvwc_reg(window, VREG(SEIDR), 0ULL); 238 write_hvwc_reg(window, VREG(FAULT_TX_WIN), 0ULL); 239 write_hvwc_reg(window, VREG(OSU_INTR_SRC_RA), 0ULL); 240 write_hvwc_reg(window, VREG(HV_INTR_SRC_RA), 0ULL); 241 write_hvwc_reg(window, VREG(PSWID), 0ULL); 242 write_hvwc_reg(window, VREG(LFIFO_BAR), 0ULL); 243 write_hvwc_reg(window, VREG(LDATA_STAMP_CTL), 0ULL); 244 write_hvwc_reg(window, VREG(LDMA_CACHE_CTL), 0ULL); 245 write_hvwc_reg(window, VREG(LRFIFO_PUSH), 0ULL); 246 write_hvwc_reg(window, VREG(CURR_MSG_COUNT), 0ULL); 247 write_hvwc_reg(window, VREG(LNOTIFY_AFTER_COUNT), 0ULL); 248 write_hvwc_reg(window, VREG(LRX_WCRED), 0ULL); 249 write_hvwc_reg(window, VREG(LRX_WCRED_ADDER), 0ULL); 250 write_hvwc_reg(window, VREG(TX_WCRED), 0ULL); 251 write_hvwc_reg(window, VREG(TX_WCRED_ADDER), 0ULL); 252 write_hvwc_reg(window, VREG(LFIFO_SIZE), 0ULL); 253 write_hvwc_reg(window, VREG(WINCTL), 0ULL); 254 write_hvwc_reg(window, VREG(WIN_STATUS), 0ULL); 255 write_hvwc_reg(window, VREG(WIN_CTX_CACHING_CTL), 0ULL); 256 write_hvwc_reg(window, VREG(TX_RSVD_BUF_COUNT), 0ULL); 257 write_hvwc_reg(window, VREG(LRFIFO_WIN_PTR), 0ULL); 258 write_hvwc_reg(window, VREG(LNOTIFY_CTL), 0ULL); 259 write_hvwc_reg(window, VREG(LNOTIFY_PID), 0ULL); 260 write_hvwc_reg(window, VREG(LNOTIFY_LPID), 0ULL); 261 write_hvwc_reg(window, VREG(LNOTIFY_TID), 0ULL); 262 write_hvwc_reg(window, VREG(LNOTIFY_SCOPE), 0ULL); 263 write_hvwc_reg(window, VREG(NX_UTIL_ADDER), 0ULL); 264 265 /* Skip read-only registers: NX_UTIL and NX_UTIL_SE */ 266 267 /* 268 * The send and receive window credit adder registers are also 269 * accessible from HVWC and have been initialized above. We don't 270 * need to initialize from the OS/User Window Context, so skip 271 * following calls: 272 * 273 * write_uwc_reg(window, VREG(TX_WCRED_ADDER), 0ULL); 274 * write_uwc_reg(window, VREG(LRX_WCRED_ADDER), 0ULL); 275 */ 276 } 277 278 /* 279 * Initialize window context registers related to Address Translation. 280 * These registers are common to send/receive windows although they 281 * differ for user/kernel windows. As we resolve the TODOs we may 282 * want to add fields to vas_winctx and move the initialization to 283 * init_vas_winctx_regs(). 284 */ 285 static void init_xlate_regs(struct vas_window *window, bool user_win) 286 { 287 u64 lpcr, val; 288 289 /* 290 * MSR_TA, MSR_US are false for both kernel and user. 291 * MSR_DR and MSR_PR are false for kernel. 292 */ 293 val = 0ULL; 294 val = SET_FIELD(VAS_XLATE_MSR_HV, val, 1); 295 val = SET_FIELD(VAS_XLATE_MSR_SF, val, 1); 296 if (user_win) { 297 val = SET_FIELD(VAS_XLATE_MSR_DR, val, 1); 298 val = SET_FIELD(VAS_XLATE_MSR_PR, val, 1); 299 } 300 write_hvwc_reg(window, VREG(XLATE_MSR), val); 301 302 lpcr = mfspr(SPRN_LPCR); 303 val = 0ULL; 304 /* 305 * NOTE: From Section 5.7.8.1 Segment Lookaside Buffer of the 306 * Power ISA, v3.0B, Page size encoding is 0 = 4KB, 5 = 64KB. 307 * 308 * NOTE: From Section 1.3.1, Address Translation Context of the 309 * Nest MMU Workbook, LPCR_SC should be 0 for Power9. 310 */ 311 val = SET_FIELD(VAS_XLATE_LPCR_PAGE_SIZE, val, 5); 312 val = SET_FIELD(VAS_XLATE_LPCR_ISL, val, lpcr & LPCR_ISL); 313 val = SET_FIELD(VAS_XLATE_LPCR_TC, val, lpcr & LPCR_TC); 314 val = SET_FIELD(VAS_XLATE_LPCR_SC, val, 0); 315 write_hvwc_reg(window, VREG(XLATE_LPCR), val); 316 317 /* 318 * Section 1.3.1 (Address translation Context) of NMMU workbook. 319 * 0b00 Hashed Page Table mode 320 * 0b01 Reserved 321 * 0b10 Radix on HPT 322 * 0b11 Radix on Radix 323 */ 324 val = 0ULL; 325 val = SET_FIELD(VAS_XLATE_MODE, val, radix_enabled() ? 3 : 2); 326 write_hvwc_reg(window, VREG(XLATE_CTL), val); 327 328 /* 329 * TODO: Can we mfspr(AMR) even for user windows? 330 */ 331 val = 0ULL; 332 val = SET_FIELD(VAS_AMR, val, mfspr(SPRN_AMR)); 333 write_hvwc_reg(window, VREG(AMR), val); 334 335 val = 0ULL; 336 val = SET_FIELD(VAS_SEIDR, val, 0); 337 write_hvwc_reg(window, VREG(SEIDR), val); 338 } 339 340 /* 341 * Initialize Reserved Send Buffer Count for the send window. It involves 342 * writing to the register, reading it back to confirm that the hardware 343 * has enough buffers to reserve. See section 1.3.1.2.1 of VAS workbook. 344 * 345 * Since we can only make a best-effort attempt to fulfill the request, 346 * we don't return any errors if we cannot. 347 * 348 * TODO: Reserved (aka dedicated) send buffers are not supported yet. 349 */ 350 static void init_rsvd_tx_buf_count(struct vas_window *txwin, 351 struct vas_winctx *winctx) 352 { 353 write_hvwc_reg(txwin, VREG(TX_RSVD_BUF_COUNT), 0ULL); 354 } 355 356 /* 357 * init_winctx_regs() 358 * Initialize window context registers for a receive window. 359 * Except for caching control and marking window open, the registers 360 * are initialized in the order listed in Section 3.1.4 (Window Context 361 * Cache Register Details) of the VAS workbook although they don't need 362 * to be. 363 * 364 * Design note: For NX receive windows, NX allocates the FIFO buffer in OPAL 365 * (so that it can get a large contiguous area) and passes that buffer 366 * to kernel via device tree. We now write that buffer address to the 367 * FIFO BAR. Would it make sense to do this all in OPAL? i.e have OPAL 368 * write the per-chip RX FIFO addresses to the windows during boot-up 369 * as a one-time task? That could work for NX but what about other 370 * receivers? Let the receivers tell us the rx-fifo buffers for now. 371 */ 372 int init_winctx_regs(struct vas_window *window, struct vas_winctx *winctx) 373 { 374 u64 val; 375 int fifo_size; 376 377 reset_window_regs(window); 378 379 val = 0ULL; 380 val = SET_FIELD(VAS_LPID, val, winctx->lpid); 381 write_hvwc_reg(window, VREG(LPID), val); 382 383 val = 0ULL; 384 val = SET_FIELD(VAS_PID_ID, val, winctx->pidr); 385 write_hvwc_reg(window, VREG(PID), val); 386 387 init_xlate_regs(window, winctx->user_win); 388 389 val = 0ULL; 390 val = SET_FIELD(VAS_FAULT_TX_WIN, val, 0); 391 write_hvwc_reg(window, VREG(FAULT_TX_WIN), val); 392 393 /* In PowerNV, interrupts go to HV. */ 394 write_hvwc_reg(window, VREG(OSU_INTR_SRC_RA), 0ULL); 395 396 val = 0ULL; 397 val = SET_FIELD(VAS_HV_INTR_SRC_RA, val, winctx->irq_port); 398 write_hvwc_reg(window, VREG(HV_INTR_SRC_RA), val); 399 400 val = 0ULL; 401 val = SET_FIELD(VAS_PSWID_EA_HANDLE, val, winctx->pswid); 402 write_hvwc_reg(window, VREG(PSWID), val); 403 404 write_hvwc_reg(window, VREG(SPARE1), 0ULL); 405 write_hvwc_reg(window, VREG(SPARE2), 0ULL); 406 write_hvwc_reg(window, VREG(SPARE3), 0ULL); 407 408 /* 409 * NOTE: VAS expects the FIFO address to be copied into the LFIFO_BAR 410 * register as is - do NOT shift the address into VAS_LFIFO_BAR 411 * bit fields! Ok to set the page migration select fields - 412 * VAS ignores the lower 10+ bits in the address anyway, because 413 * the minimum FIFO size is 1K? 414 * 415 * See also: Design note in function header. 416 */ 417 val = __pa(winctx->rx_fifo); 418 val = SET_FIELD(VAS_PAGE_MIGRATION_SELECT, val, 0); 419 write_hvwc_reg(window, VREG(LFIFO_BAR), val); 420 421 val = 0ULL; 422 val = SET_FIELD(VAS_LDATA_STAMP, val, winctx->data_stamp); 423 write_hvwc_reg(window, VREG(LDATA_STAMP_CTL), val); 424 425 val = 0ULL; 426 val = SET_FIELD(VAS_LDMA_TYPE, val, winctx->dma_type); 427 val = SET_FIELD(VAS_LDMA_FIFO_DISABLE, val, winctx->fifo_disable); 428 write_hvwc_reg(window, VREG(LDMA_CACHE_CTL), val); 429 430 write_hvwc_reg(window, VREG(LRFIFO_PUSH), 0ULL); 431 write_hvwc_reg(window, VREG(CURR_MSG_COUNT), 0ULL); 432 write_hvwc_reg(window, VREG(LNOTIFY_AFTER_COUNT), 0ULL); 433 434 val = 0ULL; 435 val = SET_FIELD(VAS_LRX_WCRED, val, winctx->wcreds_max); 436 write_hvwc_reg(window, VREG(LRX_WCRED), val); 437 438 val = 0ULL; 439 val = SET_FIELD(VAS_TX_WCRED, val, winctx->wcreds_max); 440 write_hvwc_reg(window, VREG(TX_WCRED), val); 441 442 write_hvwc_reg(window, VREG(LRX_WCRED_ADDER), 0ULL); 443 write_hvwc_reg(window, VREG(TX_WCRED_ADDER), 0ULL); 444 445 fifo_size = winctx->rx_fifo_size / 1024; 446 447 val = 0ULL; 448 val = SET_FIELD(VAS_LFIFO_SIZE, val, ilog2(fifo_size)); 449 write_hvwc_reg(window, VREG(LFIFO_SIZE), val); 450 451 /* Update window control and caching control registers last so 452 * we mark the window open only after fully initializing it and 453 * pushing context to cache. 454 */ 455 456 write_hvwc_reg(window, VREG(WIN_STATUS), 0ULL); 457 458 init_rsvd_tx_buf_count(window, winctx); 459 460 /* for a send window, point to the matching receive window */ 461 val = 0ULL; 462 val = SET_FIELD(VAS_LRX_WIN_ID, val, winctx->rx_win_id); 463 write_hvwc_reg(window, VREG(LRFIFO_WIN_PTR), val); 464 465 write_hvwc_reg(window, VREG(SPARE4), 0ULL); 466 467 val = 0ULL; 468 val = SET_FIELD(VAS_NOTIFY_DISABLE, val, winctx->notify_disable); 469 val = SET_FIELD(VAS_INTR_DISABLE, val, winctx->intr_disable); 470 val = SET_FIELD(VAS_NOTIFY_EARLY, val, winctx->notify_early); 471 val = SET_FIELD(VAS_NOTIFY_OSU_INTR, val, winctx->notify_os_intr_reg); 472 write_hvwc_reg(window, VREG(LNOTIFY_CTL), val); 473 474 val = 0ULL; 475 val = SET_FIELD(VAS_LNOTIFY_PID, val, winctx->lnotify_pid); 476 write_hvwc_reg(window, VREG(LNOTIFY_PID), val); 477 478 val = 0ULL; 479 val = SET_FIELD(VAS_LNOTIFY_LPID, val, winctx->lnotify_lpid); 480 write_hvwc_reg(window, VREG(LNOTIFY_LPID), val); 481 482 val = 0ULL; 483 val = SET_FIELD(VAS_LNOTIFY_TID, val, winctx->lnotify_tid); 484 write_hvwc_reg(window, VREG(LNOTIFY_TID), val); 485 486 val = 0ULL; 487 val = SET_FIELD(VAS_LNOTIFY_MIN_SCOPE, val, winctx->min_scope); 488 val = SET_FIELD(VAS_LNOTIFY_MAX_SCOPE, val, winctx->max_scope); 489 write_hvwc_reg(window, VREG(LNOTIFY_SCOPE), val); 490 491 /* Skip read-only registers NX_UTIL and NX_UTIL_SE */ 492 493 write_hvwc_reg(window, VREG(SPARE5), 0ULL); 494 write_hvwc_reg(window, VREG(NX_UTIL_ADDER), 0ULL); 495 write_hvwc_reg(window, VREG(SPARE6), 0ULL); 496 497 /* Finally, push window context to memory and... */ 498 val = 0ULL; 499 val = SET_FIELD(VAS_PUSH_TO_MEM, val, 1); 500 write_hvwc_reg(window, VREG(WIN_CTX_CACHING_CTL), val); 501 502 /* ... mark the window open for business */ 503 val = 0ULL; 504 val = SET_FIELD(VAS_WINCTL_REJ_NO_CREDIT, val, winctx->rej_no_credit); 505 val = SET_FIELD(VAS_WINCTL_PIN, val, winctx->pin_win); 506 val = SET_FIELD(VAS_WINCTL_TX_WCRED_MODE, val, winctx->tx_wcred_mode); 507 val = SET_FIELD(VAS_WINCTL_RX_WCRED_MODE, val, winctx->rx_wcred_mode); 508 val = SET_FIELD(VAS_WINCTL_TX_WORD_MODE, val, winctx->tx_word_mode); 509 val = SET_FIELD(VAS_WINCTL_RX_WORD_MODE, val, winctx->rx_word_mode); 510 val = SET_FIELD(VAS_WINCTL_FAULT_WIN, val, winctx->fault_win); 511 val = SET_FIELD(VAS_WINCTL_NX_WIN, val, winctx->nx_win); 512 val = SET_FIELD(VAS_WINCTL_OPEN, val, 1); 513 write_hvwc_reg(window, VREG(WINCTL), val); 514 515 return 0; 516 } 517 518 static void vas_release_window_id(struct ida *ida, int winid) 519 { 520 ida_free(ida, winid); 521 } 522 523 static int vas_assign_window_id(struct ida *ida) 524 { 525 int winid = ida_alloc_max(ida, VAS_WINDOWS_PER_CHIP - 1, GFP_KERNEL); 526 527 if (winid == -ENOSPC) { 528 pr_err("Too many (%d) open windows\n", VAS_WINDOWS_PER_CHIP); 529 return -EAGAIN; 530 } 531 532 return winid; 533 } 534 535 static void vas_window_free(struct vas_window *window) 536 { 537 int winid = window->winid; 538 struct vas_instance *vinst = window->vinst; 539 540 unmap_winctx_mmio_bars(window); 541 542 vas_window_free_dbgdir(window); 543 544 kfree(window); 545 546 vas_release_window_id(&vinst->ida, winid); 547 } 548 549 static struct vas_window *vas_window_alloc(struct vas_instance *vinst) 550 { 551 int winid; 552 struct vas_window *window; 553 554 winid = vas_assign_window_id(&vinst->ida); 555 if (winid < 0) 556 return ERR_PTR(winid); 557 558 window = kzalloc(sizeof(*window), GFP_KERNEL); 559 if (!window) 560 goto out_free; 561 562 window->vinst = vinst; 563 window->winid = winid; 564 565 if (map_winctx_mmio_bars(window)) 566 goto out_free; 567 568 vas_window_init_dbgdir(window); 569 570 return window; 571 572 out_free: 573 kfree(window); 574 vas_release_window_id(&vinst->ida, winid); 575 return ERR_PTR(-ENOMEM); 576 } 577 578 static void put_rx_win(struct vas_window *rxwin) 579 { 580 /* Better not be a send window! */ 581 WARN_ON_ONCE(rxwin->tx_win); 582 583 atomic_dec(&rxwin->num_txwins); 584 } 585 586 /* 587 * Find the user space receive window given the @pswid. 588 * - We must have a valid vasid and it must belong to this instance. 589 * (so both send and receive windows are on the same VAS instance) 590 * - The window must refer to an OPEN, FTW, RECEIVE window. 591 * 592 * NOTE: We access ->windows[] table and assume that vinst->mutex is held. 593 */ 594 static struct vas_window *get_user_rxwin(struct vas_instance *vinst, u32 pswid) 595 { 596 int vasid, winid; 597 struct vas_window *rxwin; 598 599 decode_pswid(pswid, &vasid, &winid); 600 601 if (vinst->vas_id != vasid) 602 return ERR_PTR(-EINVAL); 603 604 rxwin = vinst->windows[winid]; 605 606 if (!rxwin || rxwin->tx_win || rxwin->cop != VAS_COP_TYPE_FTW) 607 return ERR_PTR(-EINVAL); 608 609 return rxwin; 610 } 611 612 /* 613 * Get the VAS receive window associated with NX engine identified 614 * by @cop and if applicable, @pswid. 615 * 616 * See also function header of set_vinst_win(). 617 */ 618 static struct vas_window *get_vinst_rxwin(struct vas_instance *vinst, 619 enum vas_cop_type cop, u32 pswid) 620 { 621 struct vas_window *rxwin; 622 623 mutex_lock(&vinst->mutex); 624 625 if (cop == VAS_COP_TYPE_FTW) 626 rxwin = get_user_rxwin(vinst, pswid); 627 else 628 rxwin = vinst->rxwin[cop] ?: ERR_PTR(-EINVAL); 629 630 if (!IS_ERR(rxwin)) 631 atomic_inc(&rxwin->num_txwins); 632 633 mutex_unlock(&vinst->mutex); 634 635 return rxwin; 636 } 637 638 /* 639 * We have two tables of windows in a VAS instance. The first one, 640 * ->windows[], contains all the windows in the instance and allows 641 * looking up a window by its id. It is used to look up send windows 642 * during fault handling and receive windows when pairing user space 643 * send/receive windows. 644 * 645 * The second table, ->rxwin[], contains receive windows that are 646 * associated with NX engines. This table has VAS_COP_TYPE_MAX 647 * entries and is used to look up a receive window by its 648 * coprocessor type. 649 * 650 * Here, we save @window in the ->windows[] table. If it is a receive 651 * window, we also save the window in the ->rxwin[] table. 652 */ 653 static void set_vinst_win(struct vas_instance *vinst, 654 struct vas_window *window) 655 { 656 int id = window->winid; 657 658 mutex_lock(&vinst->mutex); 659 660 /* 661 * There should only be one receive window for a coprocessor type 662 * unless its a user (FTW) window. 663 */ 664 if (!window->user_win && !window->tx_win) { 665 WARN_ON_ONCE(vinst->rxwin[window->cop]); 666 vinst->rxwin[window->cop] = window; 667 } 668 669 WARN_ON_ONCE(vinst->windows[id] != NULL); 670 vinst->windows[id] = window; 671 672 mutex_unlock(&vinst->mutex); 673 } 674 675 /* 676 * Clear this window from the table(s) of windows for this VAS instance. 677 * See also function header of set_vinst_win(). 678 */ 679 static void clear_vinst_win(struct vas_window *window) 680 { 681 int id = window->winid; 682 struct vas_instance *vinst = window->vinst; 683 684 mutex_lock(&vinst->mutex); 685 686 if (!window->user_win && !window->tx_win) { 687 WARN_ON_ONCE(!vinst->rxwin[window->cop]); 688 vinst->rxwin[window->cop] = NULL; 689 } 690 691 WARN_ON_ONCE(vinst->windows[id] != window); 692 vinst->windows[id] = NULL; 693 694 mutex_unlock(&vinst->mutex); 695 } 696 697 static void init_winctx_for_rxwin(struct vas_window *rxwin, 698 struct vas_rx_win_attr *rxattr, 699 struct vas_winctx *winctx) 700 { 701 /* 702 * We first zero (memset()) all fields and only set non-zero fields. 703 * Following fields are 0/false but maybe deserve a comment: 704 * 705 * ->notify_os_intr_reg In powerNV, send intrs to HV 706 * ->notify_disable False for NX windows 707 * ->intr_disable False for Fault Windows 708 * ->xtra_write False for NX windows 709 * ->notify_early NA for NX windows 710 * ->rsvd_txbuf_count NA for Rx windows 711 * ->lpid, ->pid, ->tid NA for Rx windows 712 */ 713 714 memset(winctx, 0, sizeof(struct vas_winctx)); 715 716 winctx->rx_fifo = rxattr->rx_fifo; 717 winctx->rx_fifo_size = rxattr->rx_fifo_size; 718 winctx->wcreds_max = rxwin->wcreds_max; 719 winctx->pin_win = rxattr->pin_win; 720 721 winctx->nx_win = rxattr->nx_win; 722 winctx->fault_win = rxattr->fault_win; 723 winctx->user_win = rxattr->user_win; 724 winctx->rej_no_credit = rxattr->rej_no_credit; 725 winctx->rx_word_mode = rxattr->rx_win_ord_mode; 726 winctx->tx_word_mode = rxattr->tx_win_ord_mode; 727 winctx->rx_wcred_mode = rxattr->rx_wcred_mode; 728 winctx->tx_wcred_mode = rxattr->tx_wcred_mode; 729 winctx->notify_early = rxattr->notify_early; 730 731 if (winctx->nx_win) { 732 winctx->data_stamp = true; 733 winctx->intr_disable = true; 734 winctx->pin_win = true; 735 736 WARN_ON_ONCE(winctx->fault_win); 737 WARN_ON_ONCE(!winctx->rx_word_mode); 738 WARN_ON_ONCE(!winctx->tx_word_mode); 739 WARN_ON_ONCE(winctx->notify_after_count); 740 } else if (winctx->fault_win) { 741 winctx->notify_disable = true; 742 } else if (winctx->user_win) { 743 /* 744 * Section 1.8.1 Low Latency Core-Core Wake up of 745 * the VAS workbook: 746 * 747 * - disable credit checks ([tr]x_wcred_mode = false) 748 * - disable FIFO writes 749 * - enable ASB_Notify, disable interrupt 750 */ 751 winctx->fifo_disable = true; 752 winctx->intr_disable = true; 753 winctx->rx_fifo = NULL; 754 } 755 756 winctx->lnotify_lpid = rxattr->lnotify_lpid; 757 winctx->lnotify_pid = rxattr->lnotify_pid; 758 winctx->lnotify_tid = rxattr->lnotify_tid; 759 winctx->pswid = rxattr->pswid; 760 winctx->dma_type = VAS_DMA_TYPE_INJECT; 761 winctx->tc_mode = rxattr->tc_mode; 762 763 winctx->min_scope = VAS_SCOPE_LOCAL; 764 winctx->max_scope = VAS_SCOPE_VECTORED_GROUP; 765 } 766 767 static bool rx_win_args_valid(enum vas_cop_type cop, 768 struct vas_rx_win_attr *attr) 769 { 770 pr_debug("Rxattr: fault %d, notify %d, intr %d, early %d, fifo %d\n", 771 attr->fault_win, attr->notify_disable, 772 attr->intr_disable, attr->notify_early, 773 attr->rx_fifo_size); 774 775 if (cop >= VAS_COP_TYPE_MAX) 776 return false; 777 778 if (cop != VAS_COP_TYPE_FTW && 779 attr->rx_fifo_size < VAS_RX_FIFO_SIZE_MIN) 780 return false; 781 782 if (attr->rx_fifo_size > VAS_RX_FIFO_SIZE_MAX) 783 return false; 784 785 if (attr->wcreds_max > VAS_RX_WCREDS_MAX) 786 return false; 787 788 if (attr->nx_win) { 789 /* cannot be fault or user window if it is nx */ 790 if (attr->fault_win || attr->user_win) 791 return false; 792 /* 793 * Section 3.1.4.32: NX Windows must not disable notification, 794 * and must not enable interrupts or early notification. 795 */ 796 if (attr->notify_disable || !attr->intr_disable || 797 attr->notify_early) 798 return false; 799 } else if (attr->fault_win) { 800 /* cannot be both fault and user window */ 801 if (attr->user_win) 802 return false; 803 804 /* 805 * Section 3.1.4.32: Fault windows must disable notification 806 * but not interrupts. 807 */ 808 if (!attr->notify_disable || attr->intr_disable) 809 return false; 810 811 } else if (attr->user_win) { 812 /* 813 * User receive windows are only for fast-thread-wakeup 814 * (FTW). They don't need a FIFO and must disable interrupts 815 */ 816 if (attr->rx_fifo || attr->rx_fifo_size || !attr->intr_disable) 817 return false; 818 } else { 819 /* Rx window must be one of NX or Fault or User window. */ 820 return false; 821 } 822 823 return true; 824 } 825 826 void vas_init_rx_win_attr(struct vas_rx_win_attr *rxattr, enum vas_cop_type cop) 827 { 828 memset(rxattr, 0, sizeof(*rxattr)); 829 830 if (cop == VAS_COP_TYPE_842 || cop == VAS_COP_TYPE_842_HIPRI) { 831 rxattr->pin_win = true; 832 rxattr->nx_win = true; 833 rxattr->fault_win = false; 834 rxattr->intr_disable = true; 835 rxattr->rx_wcred_mode = true; 836 rxattr->tx_wcred_mode = true; 837 rxattr->rx_win_ord_mode = true; 838 rxattr->tx_win_ord_mode = true; 839 } else if (cop == VAS_COP_TYPE_FAULT) { 840 rxattr->pin_win = true; 841 rxattr->fault_win = true; 842 rxattr->notify_disable = true; 843 rxattr->rx_wcred_mode = true; 844 rxattr->tx_wcred_mode = true; 845 rxattr->rx_win_ord_mode = true; 846 rxattr->tx_win_ord_mode = true; 847 } else if (cop == VAS_COP_TYPE_FTW) { 848 rxattr->user_win = true; 849 rxattr->intr_disable = true; 850 851 /* 852 * As noted in the VAS Workbook we disable credit checks. 853 * If we enable credit checks in the future, we must also 854 * implement a mechanism to return the user credits or new 855 * paste operations will fail. 856 */ 857 } 858 } 859 EXPORT_SYMBOL_GPL(vas_init_rx_win_attr); 860 861 struct vas_window *vas_rx_win_open(int vasid, enum vas_cop_type cop, 862 struct vas_rx_win_attr *rxattr) 863 { 864 struct vas_window *rxwin; 865 struct vas_winctx winctx; 866 struct vas_instance *vinst; 867 868 trace_vas_rx_win_open(current, vasid, cop, rxattr); 869 870 if (!rx_win_args_valid(cop, rxattr)) 871 return ERR_PTR(-EINVAL); 872 873 vinst = find_vas_instance(vasid); 874 if (!vinst) { 875 pr_devel("vasid %d not found!\n", vasid); 876 return ERR_PTR(-EINVAL); 877 } 878 pr_devel("Found instance %d\n", vasid); 879 880 rxwin = vas_window_alloc(vinst); 881 if (IS_ERR(rxwin)) { 882 pr_devel("Unable to allocate memory for Rx window\n"); 883 return rxwin; 884 } 885 886 rxwin->tx_win = false; 887 rxwin->nx_win = rxattr->nx_win; 888 rxwin->user_win = rxattr->user_win; 889 rxwin->cop = cop; 890 rxwin->wcreds_max = rxattr->wcreds_max ?: VAS_WCREDS_DEFAULT; 891 if (rxattr->user_win) 892 rxwin->pid = task_pid_vnr(current); 893 894 init_winctx_for_rxwin(rxwin, rxattr, &winctx); 895 init_winctx_regs(rxwin, &winctx); 896 897 set_vinst_win(vinst, rxwin); 898 899 return rxwin; 900 } 901 EXPORT_SYMBOL_GPL(vas_rx_win_open); 902 903 void vas_init_tx_win_attr(struct vas_tx_win_attr *txattr, enum vas_cop_type cop) 904 { 905 memset(txattr, 0, sizeof(*txattr)); 906 907 if (cop == VAS_COP_TYPE_842 || cop == VAS_COP_TYPE_842_HIPRI) { 908 txattr->rej_no_credit = false; 909 txattr->rx_wcred_mode = true; 910 txattr->tx_wcred_mode = true; 911 txattr->rx_win_ord_mode = true; 912 txattr->tx_win_ord_mode = true; 913 } else if (cop == VAS_COP_TYPE_FTW) { 914 txattr->user_win = true; 915 } 916 } 917 EXPORT_SYMBOL_GPL(vas_init_tx_win_attr); 918 919 static void init_winctx_for_txwin(struct vas_window *txwin, 920 struct vas_tx_win_attr *txattr, 921 struct vas_winctx *winctx) 922 { 923 /* 924 * We first zero all fields and only set non-zero ones. Following 925 * are some fields set to 0/false for the stated reason: 926 * 927 * ->notify_os_intr_reg In powernv, send intrs to HV 928 * ->rsvd_txbuf_count Not supported yet. 929 * ->notify_disable False for NX windows 930 * ->xtra_write False for NX windows 931 * ->notify_early NA for NX windows 932 * ->lnotify_lpid NA for Tx windows 933 * ->lnotify_pid NA for Tx windows 934 * ->lnotify_tid NA for Tx windows 935 * ->tx_win_cred_mode Ignore for now for NX windows 936 * ->rx_win_cred_mode Ignore for now for NX windows 937 */ 938 memset(winctx, 0, sizeof(struct vas_winctx)); 939 940 winctx->wcreds_max = txwin->wcreds_max; 941 942 winctx->user_win = txattr->user_win; 943 winctx->nx_win = txwin->rxwin->nx_win; 944 winctx->pin_win = txattr->pin_win; 945 winctx->rej_no_credit = txattr->rej_no_credit; 946 winctx->rsvd_txbuf_enable = txattr->rsvd_txbuf_enable; 947 948 winctx->rx_wcred_mode = txattr->rx_wcred_mode; 949 winctx->tx_wcred_mode = txattr->tx_wcred_mode; 950 winctx->rx_word_mode = txattr->rx_win_ord_mode; 951 winctx->tx_word_mode = txattr->tx_win_ord_mode; 952 winctx->rsvd_txbuf_count = txattr->rsvd_txbuf_count; 953 954 winctx->intr_disable = true; 955 if (winctx->nx_win) 956 winctx->data_stamp = true; 957 958 winctx->lpid = txattr->lpid; 959 winctx->pidr = txattr->pidr; 960 winctx->rx_win_id = txwin->rxwin->winid; 961 962 winctx->dma_type = VAS_DMA_TYPE_INJECT; 963 winctx->tc_mode = txattr->tc_mode; 964 winctx->min_scope = VAS_SCOPE_LOCAL; 965 winctx->max_scope = VAS_SCOPE_VECTORED_GROUP; 966 967 winctx->pswid = 0; 968 } 969 970 static bool tx_win_args_valid(enum vas_cop_type cop, 971 struct vas_tx_win_attr *attr) 972 { 973 if (attr->tc_mode != VAS_THRESH_DISABLED) 974 return false; 975 976 if (cop > VAS_COP_TYPE_MAX) 977 return false; 978 979 if (attr->wcreds_max > VAS_TX_WCREDS_MAX) 980 return false; 981 982 if (attr->user_win && 983 (cop != VAS_COP_TYPE_FTW || attr->rsvd_txbuf_count)) 984 return false; 985 986 return true; 987 } 988 989 struct vas_window *vas_tx_win_open(int vasid, enum vas_cop_type cop, 990 struct vas_tx_win_attr *attr) 991 { 992 int rc; 993 struct vas_window *txwin; 994 struct vas_window *rxwin; 995 struct vas_winctx winctx; 996 struct vas_instance *vinst; 997 998 trace_vas_tx_win_open(current, vasid, cop, attr); 999 1000 if (!tx_win_args_valid(cop, attr)) 1001 return ERR_PTR(-EINVAL); 1002 1003 /* 1004 * If caller did not specify a vasid but specified the PSWID of a 1005 * receive window (applicable only to FTW windows), use the vasid 1006 * from that receive window. 1007 */ 1008 if (vasid == -1 && attr->pswid) 1009 decode_pswid(attr->pswid, &vasid, NULL); 1010 1011 vinst = find_vas_instance(vasid); 1012 if (!vinst) { 1013 pr_devel("vasid %d not found!\n", vasid); 1014 return ERR_PTR(-EINVAL); 1015 } 1016 1017 rxwin = get_vinst_rxwin(vinst, cop, attr->pswid); 1018 if (IS_ERR(rxwin)) { 1019 pr_devel("No RxWin for vasid %d, cop %d\n", vasid, cop); 1020 return rxwin; 1021 } 1022 1023 txwin = vas_window_alloc(vinst); 1024 if (IS_ERR(txwin)) { 1025 rc = PTR_ERR(txwin); 1026 goto put_rxwin; 1027 } 1028 1029 txwin->cop = cop; 1030 txwin->tx_win = 1; 1031 txwin->rxwin = rxwin; 1032 txwin->nx_win = txwin->rxwin->nx_win; 1033 txwin->pid = attr->pid; 1034 txwin->user_win = attr->user_win; 1035 txwin->wcreds_max = attr->wcreds_max ?: VAS_WCREDS_DEFAULT; 1036 1037 init_winctx_for_txwin(txwin, attr, &winctx); 1038 1039 init_winctx_regs(txwin, &winctx); 1040 1041 /* 1042 * If its a kernel send window, map the window address into the 1043 * kernel's address space. For user windows, user must issue an 1044 * mmap() to map the window into their address space. 1045 * 1046 * NOTE: If kernel ever resubmits a user CRB after handling a page 1047 * fault, we will need to map this into kernel as well. 1048 */ 1049 if (!txwin->user_win) { 1050 txwin->paste_kaddr = map_paste_region(txwin); 1051 if (IS_ERR(txwin->paste_kaddr)) { 1052 rc = PTR_ERR(txwin->paste_kaddr); 1053 goto free_window; 1054 } 1055 } else { 1056 /* 1057 * A user mapping must ensure that context switch issues 1058 * CP_ABORT for this thread. 1059 */ 1060 rc = set_thread_uses_vas(); 1061 if (rc) 1062 goto free_window; 1063 } 1064 1065 set_vinst_win(vinst, txwin); 1066 1067 return txwin; 1068 1069 free_window: 1070 vas_window_free(txwin); 1071 1072 put_rxwin: 1073 put_rx_win(rxwin); 1074 return ERR_PTR(rc); 1075 1076 } 1077 EXPORT_SYMBOL_GPL(vas_tx_win_open); 1078 1079 int vas_copy_crb(void *crb, int offset) 1080 { 1081 return vas_copy(crb, offset); 1082 } 1083 EXPORT_SYMBOL_GPL(vas_copy_crb); 1084 1085 #define RMA_LSMP_REPORT_ENABLE PPC_BIT(53) 1086 int vas_paste_crb(struct vas_window *txwin, int offset, bool re) 1087 { 1088 int rc; 1089 void *addr; 1090 uint64_t val; 1091 1092 trace_vas_paste_crb(current, txwin); 1093 1094 /* 1095 * Only NX windows are supported for now and hardware assumes 1096 * report-enable flag is set for NX windows. Ensure software 1097 * complies too. 1098 */ 1099 WARN_ON_ONCE(txwin->nx_win && !re); 1100 1101 addr = txwin->paste_kaddr; 1102 if (re) { 1103 /* 1104 * Set the REPORT_ENABLE bit (equivalent to writing 1105 * to 1K offset of the paste address) 1106 */ 1107 val = SET_FIELD(RMA_LSMP_REPORT_ENABLE, 0ULL, 1); 1108 addr += val; 1109 } 1110 1111 /* 1112 * Map the raw CR value from vas_paste() to an error code (there 1113 * is just pass or fail for now though). 1114 */ 1115 rc = vas_paste(addr, offset); 1116 if (rc == 2) 1117 rc = 0; 1118 else 1119 rc = -EINVAL; 1120 1121 pr_debug("Txwin #%d: Msg count %llu\n", txwin->winid, 1122 read_hvwc_reg(txwin, VREG(LRFIFO_PUSH))); 1123 1124 return rc; 1125 } 1126 EXPORT_SYMBOL_GPL(vas_paste_crb); 1127 1128 /* 1129 * If credit checking is enabled for this window, poll for the return 1130 * of window credits (i.e for NX engines to process any outstanding CRBs). 1131 * Since NX-842 waits for the CRBs to be processed before closing the 1132 * window, we should not have to wait for too long. 1133 * 1134 * TODO: We retry in 10ms intervals now. We could/should probably peek at 1135 * the VAS_LRFIFO_PUSH_OFFSET register to get an estimate of pending 1136 * CRBs on the FIFO and compute the delay dynamically on each retry. 1137 * But that is not really needed until we support NX-GZIP access from 1138 * user space. (NX-842 driver waits for CSB and Fast thread-wakeup 1139 * doesn't use credit checking). 1140 */ 1141 static void poll_window_credits(struct vas_window *window) 1142 { 1143 u64 val; 1144 int creds, mode; 1145 1146 val = read_hvwc_reg(window, VREG(WINCTL)); 1147 if (window->tx_win) 1148 mode = GET_FIELD(VAS_WINCTL_TX_WCRED_MODE, val); 1149 else 1150 mode = GET_FIELD(VAS_WINCTL_RX_WCRED_MODE, val); 1151 1152 if (!mode) 1153 return; 1154 retry: 1155 if (window->tx_win) { 1156 val = read_hvwc_reg(window, VREG(TX_WCRED)); 1157 creds = GET_FIELD(VAS_TX_WCRED, val); 1158 } else { 1159 val = read_hvwc_reg(window, VREG(LRX_WCRED)); 1160 creds = GET_FIELD(VAS_LRX_WCRED, val); 1161 } 1162 1163 if (creds < window->wcreds_max) { 1164 val = 0; 1165 set_current_state(TASK_UNINTERRUPTIBLE); 1166 schedule_timeout(msecs_to_jiffies(10)); 1167 goto retry; 1168 } 1169 } 1170 1171 /* 1172 * Wait for the window to go to "not-busy" state. It should only take a 1173 * short time to queue a CRB, so window should not be busy for too long. 1174 * Trying 5ms intervals. 1175 */ 1176 static void poll_window_busy_state(struct vas_window *window) 1177 { 1178 int busy; 1179 u64 val; 1180 1181 retry: 1182 val = read_hvwc_reg(window, VREG(WIN_STATUS)); 1183 busy = GET_FIELD(VAS_WIN_BUSY, val); 1184 if (busy) { 1185 val = 0; 1186 set_current_state(TASK_UNINTERRUPTIBLE); 1187 schedule_timeout(msecs_to_jiffies(5)); 1188 goto retry; 1189 } 1190 } 1191 1192 /* 1193 * Have the hardware cast a window out of cache and wait for it to 1194 * be completed. 1195 * 1196 * NOTE: It can take a relatively long time to cast the window context 1197 * out of the cache. It is not strictly necessary to cast out if: 1198 * 1199 * - we clear the "Pin Window" bit (so hardware is free to evict) 1200 * 1201 * - we re-initialize the window context when it is reassigned. 1202 * 1203 * We do the former in vas_win_close() and latter in vas_win_open(). 1204 * So, ignoring the cast-out for now. We can add it as needed. If 1205 * casting out becomes necessary we should consider offloading the 1206 * job to a worker thread, so the window close can proceed quickly. 1207 */ 1208 static void poll_window_castout(struct vas_window *window) 1209 { 1210 /* stub for now */ 1211 } 1212 1213 /* 1214 * Unpin and close a window so no new requests are accepted and the 1215 * hardware can evict this window from cache if necessary. 1216 */ 1217 static void unpin_close_window(struct vas_window *window) 1218 { 1219 u64 val; 1220 1221 val = read_hvwc_reg(window, VREG(WINCTL)); 1222 val = SET_FIELD(VAS_WINCTL_PIN, val, 0); 1223 val = SET_FIELD(VAS_WINCTL_OPEN, val, 0); 1224 write_hvwc_reg(window, VREG(WINCTL), val); 1225 } 1226 1227 /* 1228 * Close a window. 1229 * 1230 * See Section 1.12.1 of VAS workbook v1.05 for details on closing window: 1231 * - Disable new paste operations (unmap paste address) 1232 * - Poll for the "Window Busy" bit to be cleared 1233 * - Clear the Open/Enable bit for the Window. 1234 * - Poll for return of window Credits (implies FIFO empty for Rx win?) 1235 * - Unpin and cast window context out of cache 1236 * 1237 * Besides the hardware, kernel has some bookkeeping of course. 1238 */ 1239 int vas_win_close(struct vas_window *window) 1240 { 1241 if (!window) 1242 return 0; 1243 1244 if (!window->tx_win && atomic_read(&window->num_txwins) != 0) { 1245 pr_devel("Attempting to close an active Rx window!\n"); 1246 WARN_ON_ONCE(1); 1247 return -EBUSY; 1248 } 1249 1250 unmap_paste_region(window); 1251 1252 clear_vinst_win(window); 1253 1254 poll_window_busy_state(window); 1255 1256 unpin_close_window(window); 1257 1258 poll_window_credits(window); 1259 1260 poll_window_castout(window); 1261 1262 /* if send window, drop reference to matching receive window */ 1263 if (window->tx_win) 1264 put_rx_win(window->rxwin); 1265 1266 vas_window_free(window); 1267 1268 return 0; 1269 } 1270 EXPORT_SYMBOL_GPL(vas_win_close); 1271 1272 /* 1273 * Return a system-wide unique window id for the window @win. 1274 */ 1275 u32 vas_win_id(struct vas_window *win) 1276 { 1277 return encode_pswid(win->vinst->vas_id, win->winid); 1278 } 1279 EXPORT_SYMBOL_GPL(vas_win_id); 1280