| 1 | /* |
| 2 | * Copyright (c) 2000-2020 Apple Inc. All rights reserved. |
| 3 | * |
| 4 | * @APPLE_OSREFERENCE_LICENSE_HEADER_START@ |
| 5 | * |
| 6 | * This file contains Original Code and/or Modifications of Original Code |
| 7 | * as defined in and that are subject to the Apple Public Source License |
| 8 | * Version 2.0 (the 'License'). You may not use this file except in |
| 9 | * compliance with the License. The rights granted to you under the License |
| 10 | * may not be used to create, or enable the creation or redistribution of, |
| 11 | * unlawful or unlicensed copies of an Apple operating system, or to |
| 12 | * circumvent, violate, or enable the circumvention or violation of, any |
| 13 | * terms of an Apple operating system software license agreement. |
| 14 | * |
| 15 | * Please obtain a copy of the License at |
| 16 | * http://www.opensource.apple.com/apsl/ and read it before using this file. |
| 17 | * |
| 18 | * The Original Code and all software distributed under the License are |
| 19 | * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER |
| 20 | * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, |
| 21 | * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, |
| 22 | * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. |
| 23 | * Please see the License for the specific language governing rights and |
| 24 | * limitations under the License. |
| 25 | * |
| 26 | * @APPLE_OSREFERENCE_LICENSE_HEADER_END@ |
| 27 | */ |
| 28 | /* |
| 29 | * Mach Operating System |
| 30 | * Copyright (c) 1987 Carnegie-Mellon University |
| 31 | * All rights reserved. The CMU software License Agreement specifies |
| 32 | * the terms and conditions for use and redistribution. |
| 33 | */ |
| 34 | /* |
| 35 | * File: vnode_pager.c |
| 36 | * |
| 37 | * "Swap" pager that pages to/from vnodes. Also |
| 38 | * handles demand paging from files. |
| 39 | * |
| 40 | */ |
| 41 | |
| 42 | #include <mach/boolean.h> |
| 43 | #include <sys/param.h> |
| 44 | #include <sys/systm.h> |
| 45 | #include <sys/user.h> |
| 46 | #include <sys/proc.h> |
| 47 | #include <sys/kauth.h> |
| 48 | #include <sys/buf.h> |
| 49 | #include <sys/uio.h> |
| 50 | #include <sys/vnode_internal.h> |
| 51 | #include <sys/namei.h> |
| 52 | #include <sys/mount_internal.h> /* needs internal due to fhandle_t */ |
| 53 | #include <sys/ubc_internal.h> |
| 54 | #include <sys/lock.h> |
| 55 | #include <sys/disk.h> /* For DKIOC calls */ |
| 56 | |
| 57 | #include <mach/mach_types.h> |
| 58 | #include <mach/memory_object_types.h> |
| 59 | #include <mach/vm_map.h> |
| 60 | #include <mach/mach_vm.h> |
| 61 | #include <mach/upl.h> |
| 62 | #include <mach/sdt.h> |
| 63 | |
| 64 | #include <vm/vm_map.h> |
| 65 | #include <vm/vm_kern.h> |
| 66 | #include <kern/zalloc.h> |
| 67 | #include <libkern/libkern.h> |
| 68 | |
| 69 | #include <vm/vnode_pager.h> |
| 70 | #include <vm/vm_pageout.h> |
| 71 | |
| 72 | #include <kern/assert.h> |
| 73 | #include <sys/kdebug.h> |
| 74 | #include <nfs/nfs.h> |
| 75 | |
| 76 | #include <vm/vm_protos.h> |
| 77 | |
| 78 | #include <sys/kdebug_triage.h> |
| 79 | #include <vfs/vfs_disk_conditioner.h> |
| 80 | |
| 81 | void |
| 82 | (void) |
| 83 | { |
| 84 | if (current_uthread()->uu_lowpri_window) { |
| 85 | throttle_lowpri_io(sleep_amount: 1); |
| 86 | } |
| 87 | } |
| 88 | |
| 89 | boolean_t |
| 90 | (vnode_t vp) |
| 91 | { |
| 92 | return disk_conditioner_mount_is_ssd(vp->v_mount); |
| 93 | } |
| 94 | |
| 95 | #if FBDP_DEBUG_OBJECT_NO_PAGER |
| 96 | bool |
| 97 | vnode_pager_forced_unmount(vnode_t vp) |
| 98 | { |
| 99 | mount_t mnt; |
| 100 | mnt = vnode_mount(vp); |
| 101 | if (!mnt) { |
| 102 | return false; |
| 103 | } |
| 104 | return vfs_isforce(mnt); |
| 105 | } |
| 106 | #endif /* FBDP_DEBUG_OBJECT_NO_PAGER */ |
| 107 | |
| 108 | #if CONFIG_IOSCHED |
| 109 | void |
| 110 | (struct vnode *devvp, uint64_t blkno, uint32_t len, int priority) |
| 111 | { |
| 112 | u_int32_t blocksize = 0; |
| 113 | dk_extent_t extent; |
| 114 | dk_set_tier_t set_tier; |
| 115 | int error = 0; |
| 116 | |
| 117 | error = VNOP_IOCTL(vp: devvp, DKIOCGETBLOCKSIZE, data: (caddr_t)&blocksize, fflag: 0, ctx: vfs_context_kernel()); |
| 118 | if (error) { |
| 119 | return; |
| 120 | } |
| 121 | |
| 122 | memset(s: &extent, c: 0, n: sizeof(dk_extent_t)); |
| 123 | memset(s: &set_tier, c: 0, n: sizeof(dk_set_tier_t)); |
| 124 | |
| 125 | extent.offset = blkno * (u_int64_t) blocksize; |
| 126 | extent.length = len; |
| 127 | |
| 128 | set_tier.extents = &extent; |
| 129 | set_tier.extentsCount = 1; |
| 130 | set_tier.tier = (uint8_t)priority; |
| 131 | |
| 132 | error = VNOP_IOCTL(vp: devvp, DKIOCSETTIER, data: (caddr_t)&set_tier, fflag: 0, ctx: vfs_context_kernel()); |
| 133 | return; |
| 134 | } |
| 135 | #endif |
| 136 | |
| 137 | void |
| 138 | ( |
| 139 | struct vnode *vp, |
| 140 | vm_object_offset_t s_offset, |
| 141 | vm_object_offset_t e_offset) |
| 142 | { |
| 143 | cluster_update_state(vp, s_offset, e_offset, TRUE); |
| 144 | } |
| 145 | |
| 146 | uint32_t |
| 147 | (struct vnode *vp) |
| 148 | { |
| 149 | if (vp->v_usecount > vp->v_kusecount) { |
| 150 | return 1; |
| 151 | } |
| 152 | return 0; |
| 153 | } |
| 154 | |
| 155 | uint32_t |
| 156 | (struct vnode *vp, uint32_t *limit) |
| 157 | { |
| 158 | return cluster_throttle_io_limit(vp, limit); |
| 159 | } |
| 160 | |
| 161 | vm_object_offset_t |
| 162 | (struct vnode *vp) |
| 163 | { |
| 164 | return (vm_object_offset_t) ubc_getsize(vp); |
| 165 | } |
| 166 | |
| 167 | extern int safe_getpath(struct vnode *dvp, char *leafname, char *path, int _len, int *truncated_path); |
| 168 | |
| 169 | kern_return_t |
| 170 | ( |
| 171 | struct vnode *vp, |
| 172 | char *pathname, |
| 173 | vm_size_t pathname_len, |
| 174 | char *filename, |
| 175 | vm_size_t filename_len, |
| 176 | boolean_t *truncated_path_p) |
| 177 | { |
| 178 | *truncated_path_p = FALSE; |
| 179 | if (pathname != NULL) { |
| 180 | /* get the path name */ |
| 181 | safe_getpath(dvp: vp, NULL, |
| 182 | path: pathname, len: (int) pathname_len, |
| 183 | truncated_path: truncated_path_p); |
| 184 | } |
| 185 | if ((pathname == NULL || *truncated_path_p) && |
| 186 | filename != NULL) { |
| 187 | /* get the file name */ |
| 188 | const char *name; |
| 189 | |
| 190 | name = vnode_getname_printable(vp); |
| 191 | strlcpy(dst: filename, src: name, n: (size_t) filename_len); |
| 192 | vnode_putname_printable(name); |
| 193 | } |
| 194 | return KERN_SUCCESS; |
| 195 | } |
| 196 | |
| 197 | kern_return_t |
| 198 | ( |
| 199 | struct vnode *vp, |
| 200 | struct timespec *current_mtime, |
| 201 | struct timespec *cs_mtime) |
| 202 | { |
| 203 | vnode_mtime(vp, current_mtime, vfs_context_current()); |
| 204 | if (cs_mtime != NULL) { |
| 205 | ubc_get_cs_mtime(vp, cs_mtime); |
| 206 | } |
| 207 | return KERN_SUCCESS; |
| 208 | } |
| 209 | |
| 210 | kern_return_t |
| 211 | ( |
| 212 | struct vnode *vp, |
| 213 | void **blobs) |
| 214 | { |
| 215 | *blobs = ubc_get_cs_blobs(vp); |
| 216 | return KERN_SUCCESS; |
| 217 | } |
| 218 | |
| 219 | /* |
| 220 | * vnode_trim: |
| 221 | * Used to call the DKIOCUNMAP ioctl on the underlying disk device for the specified vnode. |
| 222 | * Trims the region at offset bytes into the file, for length bytes. |
| 223 | * |
| 224 | * Care must be taken to ensure that the vnode is sufficiently reference counted at the time this |
| 225 | * function is called; no iocounts or usecounts are taken on the vnode. |
| 226 | * This function is non-idempotent in error cases; We cannot un-discard the blocks if only some of them |
| 227 | * are successfully discarded. |
| 228 | */ |
| 229 | u_int32_t |
| 230 | vnode_trim( |
| 231 | struct vnode *vp, |
| 232 | off_t offset, |
| 233 | size_t length) |
| 234 | { |
| 235 | daddr64_t io_blockno; /* Block number corresponding to the start of the extent */ |
| 236 | size_t io_bytecount; /* Number of bytes in current extent for the specified range */ |
| 237 | size_t trimmed = 0; |
| 238 | off_t current_offset = offset; |
| 239 | size_t remaining_length = length; |
| 240 | int error = 0; |
| 241 | u_int32_t blocksize = 0; |
| 242 | struct vnode *devvp; |
| 243 | dk_extent_t extent; |
| 244 | dk_unmap_t unmap; |
| 245 | |
| 246 | |
| 247 | /* Get the underlying device vnode */ |
| 248 | devvp = vp->v_mount->mnt_devvp; |
| 249 | |
| 250 | /* Figure out the underlying device block size */ |
| 251 | error = VNOP_IOCTL(vp: devvp, DKIOCGETBLOCKSIZE, data: (caddr_t)&blocksize, fflag: 0, ctx: vfs_context_kernel()); |
| 252 | if (error) { |
| 253 | goto trim_exit; |
| 254 | } |
| 255 | |
| 256 | /* |
| 257 | * We may not get the entire range from offset -> offset+length in a single |
| 258 | * extent from the blockmap call. Keep looping/going until we are sure we've hit |
| 259 | * the whole range or if we encounter an error. |
| 260 | */ |
| 261 | while (trimmed < length) { |
| 262 | /* |
| 263 | * VNOP_BLOCKMAP will tell us the logical to physical block number mapping for the |
| 264 | * specified offset. It returns blocks in contiguous chunks, so if the logical range is |
| 265 | * broken into multiple extents, it must be called multiple times, increasing the offset |
| 266 | * in each call to ensure that the entire range is covered. |
| 267 | */ |
| 268 | error = VNOP_BLOCKMAP(vp, current_offset, remaining_length, |
| 269 | &io_blockno, &io_bytecount, NULL, VNODE_READ | VNODE_BLOCKMAP_NO_TRACK, NULL); |
| 270 | |
| 271 | if (error) { |
| 272 | goto trim_exit; |
| 273 | } |
| 274 | /* |
| 275 | * We have a contiguous run. Prepare & issue the ioctl for the device. |
| 276 | * the DKIOCUNMAP ioctl takes offset in bytes from the start of the device. |
| 277 | */ |
| 278 | memset(s: &extent, c: 0, n: sizeof(dk_extent_t)); |
| 279 | memset(s: &unmap, c: 0, n: sizeof(dk_unmap_t)); |
| 280 | extent.offset = (uint64_t) io_blockno * (u_int64_t) blocksize; |
| 281 | extent.length = io_bytecount; |
| 282 | unmap.extents = &extent; |
| 283 | unmap.extentsCount = 1; |
| 284 | error = VNOP_IOCTL(vp: devvp, DKIOCUNMAP, data: (caddr_t)&unmap, fflag: 0, ctx: vfs_context_kernel()); |
| 285 | |
| 286 | if (error) { |
| 287 | goto trim_exit; |
| 288 | } |
| 289 | remaining_length = remaining_length - io_bytecount; |
| 290 | trimmed = trimmed + io_bytecount; |
| 291 | current_offset = current_offset + io_bytecount; |
| 292 | } |
| 293 | trim_exit: |
| 294 | |
| 295 | return error; |
| 296 | } |
| 297 | |
| 298 | pager_return_t |
| 299 | vnode_pageout(struct vnode *vp, |
| 300 | upl_t upl, |
| 301 | upl_offset_t upl_offset, |
| 302 | vm_object_offset_t f_offset, |
| 303 | upl_size_t size, |
| 304 | int flags, |
| 305 | int *errorp) |
| 306 | { |
| 307 | int result = PAGER_SUCCESS; |
| 308 | int error = 0; |
| 309 | int error_ret = 0; |
| 310 | daddr64_t blkno; |
| 311 | int isize; |
| 312 | int pg_index; |
| 313 | int base_index; |
| 314 | upl_offset_t offset; |
| 315 | upl_page_info_t *pl; |
| 316 | vfs_context_t ctx = vfs_context_current(); /* pager context */ |
| 317 | |
| 318 | isize = (int)size; |
| 319 | |
| 320 | /* |
| 321 | * This call is non-blocking and does not ever fail but it can |
| 322 | * only be made when there is other explicit synchronization |
| 323 | * with reclaiming of the vnode which, in this path, is provided |
| 324 | * by the paging in progress counter. |
| 325 | * |
| 326 | * In addition, this may also be entered via explicit ubc_msync |
| 327 | * calls or vm_swapfile_io where the existing iocount provides |
| 328 | * the necessary synchronization. Ideally we would not take an |
| 329 | * additional iocount here in the cases where an explcit iocount |
| 330 | * has already been taken but this call doesn't cause a deadlock |
| 331 | * as other forms of vnode_get* might if this thread has already |
| 332 | * taken an iocount. |
| 333 | */ |
| 334 | error = vnode_getalways_from_pager(vp); |
| 335 | if (error != 0) { |
| 336 | /* This can't happen */ |
| 337 | panic("vnode_getalways returned %d for vp %p" , error, vp); |
| 338 | } |
| 339 | |
| 340 | if (isize <= 0) { |
| 341 | result = PAGER_ERROR; |
| 342 | error_ret = EINVAL; |
| 343 | goto out; |
| 344 | } |
| 345 | |
| 346 | if (UBCINFOEXISTS(vp) == 0) { |
| 347 | result = PAGER_ERROR; |
| 348 | error_ret = EINVAL; |
| 349 | |
| 350 | if (upl && !(flags & UPL_NOCOMMIT)) { |
| 351 | ubc_upl_abort_range(upl, upl_offset, size, UPL_ABORT_FREE_ON_EMPTY); |
| 352 | } |
| 353 | goto out; |
| 354 | } |
| 355 | if (!(flags & UPL_VNODE_PAGER)) { |
| 356 | /* |
| 357 | * This is a pageout from the default pager, |
| 358 | * just go ahead and call vnop_pageout since |
| 359 | * it has already sorted out the dirty ranges |
| 360 | */ |
| 361 | KERNEL_DEBUG_CONSTANT_IST(KDEBUG_TRACE, |
| 362 | (MACHDBG_CODE(DBG_MACH_VM, 1)) | DBG_FUNC_START, |
| 363 | size, 1, 0, 0, 0); |
| 364 | |
| 365 | if ((error_ret = VNOP_PAGEOUT(vp, upl, upl_offset, (off_t)f_offset, |
| 366 | (size_t)size, flags, ctx))) { |
| 367 | result = PAGER_ERROR; |
| 368 | } |
| 369 | |
| 370 | KERNEL_DEBUG_CONSTANT_IST(KDEBUG_TRACE, |
| 371 | (MACHDBG_CODE(DBG_MACH_VM, 1)) | DBG_FUNC_END, |
| 372 | size, 1, 0, 0, 0); |
| 373 | |
| 374 | goto out; |
| 375 | } |
| 376 | if (upl == NULL) { |
| 377 | int request_flags; |
| 378 | |
| 379 | if (vp->v_mount->mnt_vtable->vfc_vfsflags & VFC_VFSVNOP_PAGEOUTV2) { |
| 380 | /* |
| 381 | * filesystem has requested the new form of VNOP_PAGEOUT for file |
| 382 | * backed objects... we will not grab the UPL befofe calling VNOP_PAGEOUT... |
| 383 | * it is the fileystem's responsibility to grab the range we're denoting |
| 384 | * via 'f_offset' and 'size' into a UPL... this allows the filesystem to first |
| 385 | * take any locks it needs, before effectively locking the pages into a UPL... |
| 386 | */ |
| 387 | KERNEL_DEBUG_CONSTANT_IST(KDEBUG_TRACE, |
| 388 | (MACHDBG_CODE(DBG_MACH_VM, 1)) | DBG_FUNC_START, |
| 389 | size, (int)f_offset, 0, 0, 0); |
| 390 | |
| 391 | if ((error_ret = VNOP_PAGEOUT(vp, NULL, upl_offset, (off_t)f_offset, |
| 392 | size, flags, ctx))) { |
| 393 | result = PAGER_ERROR; |
| 394 | } |
| 395 | KERNEL_DEBUG_CONSTANT_IST(KDEBUG_TRACE, |
| 396 | (MACHDBG_CODE(DBG_MACH_VM, 1)) | DBG_FUNC_END, |
| 397 | size, 0, 0, 0, 0); |
| 398 | |
| 399 | goto out; |
| 400 | } |
| 401 | if (flags & UPL_MSYNC) { |
| 402 | request_flags = UPL_UBC_MSYNC | UPL_RET_ONLY_DIRTY; |
| 403 | } else { |
| 404 | request_flags = UPL_UBC_PAGEOUT | UPL_RET_ONLY_DIRTY; |
| 405 | } |
| 406 | |
| 407 | if (ubc_create_upl_kernel(vp, f_offset, size, &upl, &pl, request_flags, VM_KERN_MEMORY_FILE) != KERN_SUCCESS) { |
| 408 | result = PAGER_ERROR; |
| 409 | error_ret = EINVAL; |
| 410 | goto out; |
| 411 | } |
| 412 | upl_offset = 0; |
| 413 | } else { |
| 414 | pl = ubc_upl_pageinfo(upl); |
| 415 | } |
| 416 | |
| 417 | /* |
| 418 | * Ignore any non-present pages at the end of the |
| 419 | * UPL so that we aren't looking at a upl that |
| 420 | * may already have been freed by the preceeding |
| 421 | * aborts/completions. |
| 422 | */ |
| 423 | base_index = upl_offset / PAGE_SIZE; |
| 424 | |
| 425 | for (pg_index = (upl_offset + isize) / PAGE_SIZE; pg_index > base_index;) { |
| 426 | if (upl_page_present(upl: pl, index: --pg_index)) { |
| 427 | break; |
| 428 | } |
| 429 | if (pg_index == base_index) { |
| 430 | /* |
| 431 | * no pages were returned, so release |
| 432 | * our hold on the upl and leave |
| 433 | */ |
| 434 | if (!(flags & UPL_NOCOMMIT)) { |
| 435 | ubc_upl_abort_range(upl, upl_offset, isize, UPL_ABORT_FREE_ON_EMPTY); |
| 436 | } |
| 437 | |
| 438 | goto out; |
| 439 | } |
| 440 | } |
| 441 | isize = ((pg_index + 1) - base_index) * PAGE_SIZE; |
| 442 | |
| 443 | /* |
| 444 | * we come here for pageouts to 'real' files and |
| 445 | * for msyncs... the upl may not contain any |
| 446 | * dirty pages.. it's our responsibility to sort |
| 447 | * through it and find the 'runs' of dirty pages |
| 448 | * to call VNOP_PAGEOUT on... |
| 449 | */ |
| 450 | |
| 451 | if (ubc_getsize(vp) == 0) { |
| 452 | /* |
| 453 | * if the file has been effectively deleted, then |
| 454 | * we need to go through the UPL and invalidate any |
| 455 | * buffer headers we might have that reference any |
| 456 | * of it's pages |
| 457 | */ |
| 458 | for (offset = upl_offset; isize; isize -= PAGE_SIZE, offset += PAGE_SIZE) { |
| 459 | if (vp->v_tag == VT_NFS) { |
| 460 | /* check with nfs if page is OK to drop */ |
| 461 | error = nfs_buf_page_inval(vp, (off_t)f_offset); |
| 462 | } else { |
| 463 | blkno = ubc_offtoblk(vp, (off_t)f_offset); |
| 464 | error = buf_invalblkno(vp, lblkno: blkno, flags: 0); |
| 465 | } |
| 466 | if (error) { |
| 467 | if (!(flags & UPL_NOCOMMIT)) { |
| 468 | ubc_upl_abort_range(upl, offset, PAGE_SIZE, UPL_ABORT_FREE_ON_EMPTY); |
| 469 | } |
| 470 | if (error_ret == 0) { |
| 471 | error_ret = error; |
| 472 | } |
| 473 | result = PAGER_ERROR; |
| 474 | } else if (!(flags & UPL_NOCOMMIT)) { |
| 475 | ubc_upl_commit_range(upl, offset, PAGE_SIZE, UPL_COMMIT_FREE_ON_EMPTY); |
| 476 | } |
| 477 | f_offset += PAGE_SIZE; |
| 478 | } |
| 479 | goto out; |
| 480 | } |
| 481 | |
| 482 | offset = upl_offset; |
| 483 | pg_index = base_index; |
| 484 | |
| 485 | while (isize) { |
| 486 | int xsize; |
| 487 | int num_of_pages; |
| 488 | |
| 489 | if (!upl_page_present(upl: pl, index: pg_index)) { |
| 490 | /* |
| 491 | * we asked for RET_ONLY_DIRTY, so it's possible |
| 492 | * to get back empty slots in the UPL |
| 493 | * just skip over them |
| 494 | */ |
| 495 | f_offset += PAGE_SIZE; |
| 496 | offset += PAGE_SIZE; |
| 497 | isize -= PAGE_SIZE; |
| 498 | pg_index++; |
| 499 | |
| 500 | continue; |
| 501 | } |
| 502 | if (!upl_dirty_page(upl: pl, index: pg_index)) { |
| 503 | /* |
| 504 | * if the page is not dirty and reached here it is |
| 505 | * marked precious or it is due to invalidation in |
| 506 | * memory_object_lock request as part of truncation |
| 507 | * We also get here from vm_object_terminate() |
| 508 | * So all you need to do in these |
| 509 | * cases is to invalidate incore buffer if it is there |
| 510 | * Note we must not sleep here if the buffer is busy - that is |
| 511 | * a lock inversion which causes deadlock. |
| 512 | */ |
| 513 | if (vp->v_tag == VT_NFS) { |
| 514 | /* check with nfs if page is OK to drop */ |
| 515 | error = nfs_buf_page_inval(vp, (off_t)f_offset); |
| 516 | } else { |
| 517 | blkno = ubc_offtoblk(vp, (off_t)f_offset); |
| 518 | error = buf_invalblkno(vp, lblkno: blkno, flags: 0); |
| 519 | } |
| 520 | if (error) { |
| 521 | if (!(flags & UPL_NOCOMMIT)) { |
| 522 | ubc_upl_abort_range(upl, offset, PAGE_SIZE, UPL_ABORT_FREE_ON_EMPTY); |
| 523 | } |
| 524 | if (error_ret == 0) { |
| 525 | error_ret = error; |
| 526 | } |
| 527 | result = PAGER_ERROR; |
| 528 | } else if (!(flags & UPL_NOCOMMIT)) { |
| 529 | ubc_upl_commit_range(upl, offset, PAGE_SIZE, UPL_COMMIT_FREE_ON_EMPTY); |
| 530 | } |
| 531 | f_offset += PAGE_SIZE; |
| 532 | offset += PAGE_SIZE; |
| 533 | isize -= PAGE_SIZE; |
| 534 | pg_index++; |
| 535 | |
| 536 | continue; |
| 537 | } |
| 538 | num_of_pages = 1; |
| 539 | xsize = isize - PAGE_SIZE; |
| 540 | |
| 541 | while (xsize) { |
| 542 | if (!upl_dirty_page(upl: pl, index: pg_index + num_of_pages)) { |
| 543 | break; |
| 544 | } |
| 545 | num_of_pages++; |
| 546 | xsize -= PAGE_SIZE; |
| 547 | } |
| 548 | xsize = num_of_pages * PAGE_SIZE; |
| 549 | |
| 550 | KERNEL_DEBUG_CONSTANT_IST(KDEBUG_TRACE, |
| 551 | (MACHDBG_CODE(DBG_MACH_VM, 1)) | DBG_FUNC_START, |
| 552 | xsize, (int)f_offset, 0, 0, 0); |
| 553 | |
| 554 | if ((error = VNOP_PAGEOUT(vp, upl, offset, (off_t)f_offset, |
| 555 | xsize, flags, ctx))) { |
| 556 | if (error_ret == 0) { |
| 557 | error_ret = error; |
| 558 | } |
| 559 | result = PAGER_ERROR; |
| 560 | } |
| 561 | KERNEL_DEBUG_CONSTANT_IST(KDEBUG_TRACE, |
| 562 | (MACHDBG_CODE(DBG_MACH_VM, 1)) | DBG_FUNC_END, |
| 563 | xsize, 0, 0, 0, 0); |
| 564 | |
| 565 | f_offset += xsize; |
| 566 | offset += xsize; |
| 567 | isize -= xsize; |
| 568 | pg_index += num_of_pages; |
| 569 | } |
| 570 | out: |
| 571 | vnode_put_from_pager(vp); |
| 572 | |
| 573 | if (errorp) { |
| 574 | *errorp = error_ret; |
| 575 | } |
| 576 | |
| 577 | return result; |
| 578 | } |
| 579 | |
| 580 | |
| 581 | pager_return_t |
| 582 | vnode_pagein( |
| 583 | struct vnode *vp, |
| 584 | upl_t upl, |
| 585 | upl_offset_t upl_offset, |
| 586 | vm_object_offset_t f_offset, |
| 587 | upl_size_t size, |
| 588 | int flags, |
| 589 | int *errorp) |
| 590 | { |
| 591 | upl_page_info_t *pl; |
| 592 | int result = PAGER_SUCCESS; |
| 593 | int error = 0; |
| 594 | int pages_in_upl; |
| 595 | int start_pg; |
| 596 | int last_pg; |
| 597 | int first_pg; |
| 598 | int xsize; |
| 599 | int must_commit = 1; |
| 600 | int ignore_valid_page_check = 0; |
| 601 | |
| 602 | if (flags & UPL_NOCOMMIT) { |
| 603 | must_commit = 0; |
| 604 | } |
| 605 | |
| 606 | if (flags & UPL_IGNORE_VALID_PAGE_CHECK) { |
| 607 | ignore_valid_page_check = 1; |
| 608 | } |
| 609 | |
| 610 | /* |
| 611 | * This call is non-blocking and does not ever fail but it can |
| 612 | * only be made when there is other explicit synchronization |
| 613 | * with reclaiming of the vnode which, in this path, is provided |
| 614 | * by the paging in progress counter. |
| 615 | * |
| 616 | * In addition, this may also be entered via vm_swapfile_io |
| 617 | * where the existing iocount provides the necessary synchronization. |
| 618 | * Ideally we would not take an additional iocount here in the cases |
| 619 | * where an explcit iocount has already been taken but this call |
| 620 | * doesn't cause a deadlock as other forms of vnode_get* might if |
| 621 | * this thread has already taken an iocount. |
| 622 | */ |
| 623 | error = vnode_getalways_from_pager(vp); |
| 624 | if (error != 0) { |
| 625 | /* This can't happen */ |
| 626 | panic("vnode_getalways returned %d for vp %p" , error, vp); |
| 627 | } |
| 628 | |
| 629 | if (UBCINFOEXISTS(vp) == 0) { |
| 630 | result = PAGER_ERROR; |
| 631 | error = PAGER_ERROR; |
| 632 | |
| 633 | if (upl && must_commit) { |
| 634 | ubc_upl_abort_range(upl, upl_offset, size, UPL_ABORT_FREE_ON_EMPTY | UPL_ABORT_ERROR); |
| 635 | } |
| 636 | |
| 637 | ktriage_record(thread_id: thread_tid(thread: current_thread()), KDBG_TRIAGE_EVENTID(KDBG_TRIAGE_SUBSYS_VM, KDBG_TRIAGE_RESERVED, KDBG_TRIAGE_VM_VNODEPAGEIN_NO_UBCINFO), arg: 0 /* arg */); |
| 638 | goto out; |
| 639 | } |
| 640 | if (upl == (upl_t)NULL) { |
| 641 | flags &= ~UPL_NOCOMMIT; |
| 642 | |
| 643 | if (size > MAX_UPL_SIZE_BYTES) { |
| 644 | result = PAGER_ERROR; |
| 645 | error = PAGER_ERROR; |
| 646 | goto out; |
| 647 | } |
| 648 | if (vp->v_mount->mnt_vtable->vfc_vfsflags & VFC_VFSVNOP_PAGEINV2) { |
| 649 | /* |
| 650 | * filesystem has requested the new form of VNOP_PAGEIN for file |
| 651 | * backed objects... we will not grab the UPL befofe calling VNOP_PAGEIN... |
| 652 | * it is the fileystem's responsibility to grab the range we're denoting |
| 653 | * via 'f_offset' and 'size' into a UPL... this allows the filesystem to first |
| 654 | * take any locks it needs, before effectively locking the pages into a UPL... |
| 655 | * so we pass a NULL into the filesystem instead of a UPL pointer... the 'upl_offset' |
| 656 | * is used to identify the "must have" page in the extent... the filesystem is free |
| 657 | * to clip the extent to better fit the underlying FS blocksize if it desires as |
| 658 | * long as it continues to include the "must have" page... 'f_offset' + 'upl_offset' |
| 659 | * identifies that page |
| 660 | */ |
| 661 | if ((error = VNOP_PAGEIN(vp, NULL, upl_offset, (off_t)f_offset, |
| 662 | size, flags, vfs_context_current()))) { |
| 663 | set_thread_pagein_error(current_thread(), error); |
| 664 | result = PAGER_ERROR; |
| 665 | error = PAGER_ERROR; |
| 666 | ktriage_record(thread_id: thread_tid(thread: current_thread()), KDBG_TRIAGE_EVENTID(KDBG_TRIAGE_SUBSYS_VM, KDBG_TRIAGE_RESERVED, KDBG_TRIAGE_VM_VNODEPAGEIN_FSPAGEIN_FAIL), arg: 0 /* arg */); |
| 667 | } |
| 668 | goto out; |
| 669 | } |
| 670 | ubc_create_upl_kernel(vp, f_offset, size, &upl, &pl, UPL_UBC_PAGEIN | UPL_RET_ONLY_ABSENT, VM_KERN_MEMORY_FILE); |
| 671 | |
| 672 | if (upl == (upl_t)NULL) { |
| 673 | result = PAGER_ABSENT; |
| 674 | error = PAGER_ABSENT; |
| 675 | ktriage_record(thread_id: thread_tid(thread: current_thread()), KDBG_TRIAGE_EVENTID(KDBG_TRIAGE_SUBSYS_VM, KDBG_TRIAGE_RESERVED, KDBG_TRIAGE_VM_VNODEPAGEIN_NO_UPL), arg: 0 /* arg */); |
| 676 | goto out; |
| 677 | } |
| 678 | ubc_upl_range_needed(upl, upl_offset / PAGE_SIZE, 1); |
| 679 | |
| 680 | upl_offset = 0; |
| 681 | first_pg = 0; |
| 682 | |
| 683 | /* |
| 684 | * if we get here, we've created the upl and |
| 685 | * are responsible for commiting/aborting it |
| 686 | * regardless of what the caller has passed in |
| 687 | */ |
| 688 | must_commit = 1; |
| 689 | } else { |
| 690 | pl = ubc_upl_pageinfo(upl); |
| 691 | first_pg = upl_offset / PAGE_SIZE; |
| 692 | } |
| 693 | pages_in_upl = size / PAGE_SIZE; |
| 694 | DTRACE_VM2(pgpgin, int, pages_in_upl, (uint64_t *), NULL); |
| 695 | |
| 696 | /* |
| 697 | * before we start marching forward, we must make sure we end on |
| 698 | * a present page, otherwise we will be working with a freed |
| 699 | * upl |
| 700 | */ |
| 701 | for (last_pg = pages_in_upl - 1; last_pg >= first_pg; last_pg--) { |
| 702 | if (upl_page_present(upl: pl, index: last_pg)) { |
| 703 | break; |
| 704 | } |
| 705 | if (last_pg == first_pg) { |
| 706 | /* |
| 707 | * empty UPL, no pages are present |
| 708 | */ |
| 709 | if (must_commit) { |
| 710 | ubc_upl_abort_range(upl, upl_offset, size, UPL_ABORT_FREE_ON_EMPTY); |
| 711 | } |
| 712 | goto out; |
| 713 | } |
| 714 | } |
| 715 | pages_in_upl = last_pg + 1; |
| 716 | last_pg = first_pg; |
| 717 | |
| 718 | while (last_pg < pages_in_upl) { |
| 719 | /* |
| 720 | * skip over missing pages... |
| 721 | */ |
| 722 | for (; last_pg < pages_in_upl; last_pg++) { |
| 723 | if (upl_page_present(upl: pl, index: last_pg)) { |
| 724 | break; |
| 725 | } |
| 726 | } |
| 727 | |
| 728 | if (ignore_valid_page_check == 1) { |
| 729 | start_pg = last_pg; |
| 730 | } else { |
| 731 | /* |
| 732 | * skip over 'valid' pages... we don't want to issue I/O for these |
| 733 | */ |
| 734 | for (start_pg = last_pg; last_pg < pages_in_upl; last_pg++) { |
| 735 | if (!upl_valid_page(upl: pl, index: last_pg)) { |
| 736 | break; |
| 737 | } |
| 738 | } |
| 739 | } |
| 740 | |
| 741 | if (last_pg > start_pg) { |
| 742 | /* |
| 743 | * we've found a range of valid pages |
| 744 | * if we've got COMMIT responsibility |
| 745 | * commit this range of pages back to the |
| 746 | * cache unchanged |
| 747 | */ |
| 748 | xsize = (last_pg - start_pg) * PAGE_SIZE; |
| 749 | |
| 750 | if (must_commit) { |
| 751 | ubc_upl_abort_range(upl, start_pg * PAGE_SIZE, xsize, UPL_ABORT_FREE_ON_EMPTY); |
| 752 | } |
| 753 | } |
| 754 | if (last_pg == pages_in_upl) { |
| 755 | /* |
| 756 | * we're done... all pages that were present |
| 757 | * have either had I/O issued on them or |
| 758 | * were aborted unchanged... |
| 759 | */ |
| 760 | break; |
| 761 | } |
| 762 | |
| 763 | if (!upl_page_present(upl: pl, index: last_pg)) { |
| 764 | /* |
| 765 | * we found a range of valid pages |
| 766 | * terminated by a missing page... |
| 767 | * bump index to the next page and continue on |
| 768 | */ |
| 769 | last_pg++; |
| 770 | continue; |
| 771 | } |
| 772 | /* |
| 773 | * scan from the found invalid page looking for a valid |
| 774 | * or non-present page before the end of the upl is reached, if we |
| 775 | * find one, then it will be the last page of the request to |
| 776 | * 'cluster_io' |
| 777 | */ |
| 778 | for (start_pg = last_pg; last_pg < pages_in_upl; last_pg++) { |
| 779 | if ((!ignore_valid_page_check && upl_valid_page(upl: pl, index: last_pg)) || !upl_page_present(upl: pl, index: last_pg)) { |
| 780 | break; |
| 781 | } |
| 782 | } |
| 783 | if (last_pg > start_pg) { |
| 784 | int xoff; |
| 785 | xsize = (last_pg - start_pg) * PAGE_SIZE; |
| 786 | xoff = start_pg * PAGE_SIZE; |
| 787 | |
| 788 | if ((error = VNOP_PAGEIN(vp, upl, (upl_offset_t) xoff, |
| 789 | (off_t)f_offset + xoff, |
| 790 | xsize, flags, vfs_context_current()))) { |
| 791 | /* |
| 792 | * Usually this UPL will be aborted/committed by the lower cluster layer. |
| 793 | * |
| 794 | * a) In the case of decmpfs, however, we may return an error (EAGAIN) to avoid |
| 795 | * a deadlock with another thread already inflating the file. |
| 796 | * |
| 797 | * b) In the case of content protection, EPERM is a valid error and we should respect it. |
| 798 | * |
| 799 | * In those cases, we must take care of our UPL at this layer itself. |
| 800 | */ |
| 801 | if (must_commit) { |
| 802 | if (error == EAGAIN) { |
| 803 | ubc_upl_abort_range(upl, (upl_offset_t) xoff, xsize, UPL_ABORT_FREE_ON_EMPTY | UPL_ABORT_RESTART); |
| 804 | } |
| 805 | if (error == EPERM) { |
| 806 | ubc_upl_abort_range(upl, (upl_offset_t) xoff, xsize, UPL_ABORT_FREE_ON_EMPTY | UPL_ABORT_ERROR); |
| 807 | } |
| 808 | } |
| 809 | set_thread_pagein_error(current_thread(), error); |
| 810 | result = PAGER_ERROR; |
| 811 | error = PAGER_ERROR; |
| 812 | ktriage_record(thread_id: thread_tid(thread: current_thread()), KDBG_TRIAGE_EVENTID(KDBG_TRIAGE_SUBSYS_VM, KDBG_TRIAGE_RESERVED, KDBG_TRIAGE_VM_VNODEPAGEIN_FSPAGEIN_FAIL), arg: 0 /* arg */); |
| 813 | } |
| 814 | } |
| 815 | } |
| 816 | out: |
| 817 | vnode_put_from_pager(vp); |
| 818 | |
| 819 | if (errorp) { |
| 820 | *errorp = result; |
| 821 | } |
| 822 | |
| 823 | return error; |
| 824 | } |
| 825 | |