1/*
2 * Copyright (c) 2000-2014 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/* Copyright (c) 1995 NeXT Computer, Inc. All Rights Reserved */
29/*
30 * Copyright (c) 1982, 1986, 1989, 1993
31 * The Regents of the University of California. All rights reserved.
32 * (c) UNIX System Laboratories, Inc.
33 * All or some portions of this file are derived from material licensed
34 * to the University of California by American Telephone and Telegraph
35 * Co. or Unix System Laboratories, Inc. and are reproduced herein with
36 * the permission of UNIX System Laboratories, Inc.
37 *
38 * Redistribution and use in source and binary forms, with or without
39 * modification, are permitted provided that the following conditions
40 * are met:
41 * 1. Redistributions of source code must retain the above copyright
42 * notice, this list of conditions and the following disclaimer.
43 * 2. Redistributions in binary form must reproduce the above copyright
44 * notice, this list of conditions and the following disclaimer in the
45 * documentation and/or other materials provided with the distribution.
46 * 3. All advertising materials mentioning features or use of this software
47 * must display the following acknowledgement:
48 * This product includes software developed by the University of
49 * California, Berkeley and its contributors.
50 * 4. Neither the name of the University nor the names of its contributors
51 * may be used to endorse or promote products derived from this software
52 * without specific prior written permission.
53 *
54 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
55 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
56 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
57 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
58 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
59 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
60 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
61 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
62 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
63 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
64 * SUCH DAMAGE.
65 *
66 * @(#)buf.h 8.9 (Berkeley) 3/30/95
67 */
68
69#ifndef _SYS_BUF_INTERNAL_H_
70#define _SYS_BUF_INTERNAL_H_
71
72#include <sys/appleapiopts.h>
73
74#ifdef KERNEL
75#include <sys/queue.h>
76#include <sys/errno.h>
77#include <sys/vm.h>
78#include <sys/cdefs.h>
79#include <sys/buf.h>
80#include <sys/lock.h>
81
82#if CONFIG_PROTECT
83#include <sys/cprotect.h>
84#endif
85
86#define NOLIST ((struct buf *)0x87654321)
87
88/*
89 * Attributes of an I/O to be used by lower layers
90 */
91struct bufattr {
92#if CONFIG_PROTECT
93 struct cpx *ba_cpx;
94 uint64_t ba_cp_file_off;
95#endif
96 uint64_t ba_flags; /* flags. Some are only in-use on embedded devices */
97 void *ba_verify_ctx;
98};
99
100/*
101 * The buffer header describes an I/O operation in the kernel.
102 */
103struct buf {
104 LIST_ENTRY(buf) b_hash; /* Hash chain. */
105 LIST_ENTRY(buf) b_vnbufs; /* Buffer's associated vnode. */
106 TAILQ_ENTRY(buf) b_freelist; /* Free list position if not active. */
107 int b_timestamp; /* timestamp for queuing operation */
108 struct timeval b_timestamp_tv; /* microuptime for disk conditioner */
109 int b_whichq; /* the free list the buffer belongs to */
110 volatile uint32_t b_flags; /* B_* flags. */
111 volatile uint32_t b_lflags; /* BL_BUSY | BL_WANTED flags... protected by buf_mtx */
112 int b_error; /* errno value. */
113 int b_bufsize; /* Allocated buffer size. */
114 int b_bcount; /* Valid bytes in buffer. */
115 int b_resid; /* Remaining I/O. */
116 dev_t b_dev; /* Device associated with buffer. */
117 uintptr_t b_datap; /* Memory, superblocks, indirect etc.*/
118 daddr64_t b_lblkno; /* Logical block number. */
119 daddr64_t b_blkno; /* Underlying physical block number. */
120 void (*b_iodone)(buf_t, void *); /* Function to call upon completion. */
121 vnode_t b_vp; /* File vnode for data, device vnode for metadata. */
122 kauth_cred_t b_rcred; /* Read credentials reference. */
123 kauth_cred_t b_wcred; /* Write credentials reference. */
124 void * b_upl; /* Pointer to UPL */
125 buf_t b_real_bp; /* used to track bp generated through cluster_bp */
126 TAILQ_ENTRY(buf) b_act; /* Device driver queue when active */
127 void * b_drvdata; /* Device driver private use */
128 void * b_fsprivate; /* filesystem private use */
129 void * b_transaction; /* journal private use */
130 int b_dirtyoff; /* Offset in buffer of dirty region. */
131 int b_dirtyend; /* Offset of end of dirty region. */
132 int b_validoff; /* Offset in buffer of valid region. */
133 int b_validend; /* Offset of end of valid region. */
134
135 /* store extra information related to redundancy of data, such as
136 * which redundancy copy to use, etc
137 */
138 uint32_t b_redundancy_flags;
139
140 proc_t b_proc; /* Associated proc; NULL if kernel. */
141#ifdef BUF_MAKE_PRIVATE
142 buf_t b_data_store;
143#endif
144 struct bufattr b_attr;
145#ifdef JOE_DEBUG
146 void * b_owner;
147 int b_tag;
148 void * b_lastbrelse;
149 void * b_stackbrelse[6];
150 void * b_stackgetblk[6];
151#endif
152 uint32_t b_lblksize; /* Block size used to set b_lbkno */
153 vnode_t b_vnop_vp; /* identifies vp on which VNOP has been called */
154};
155
156extern vm_offset_t buf_kernel_addrperm;
157
158/* cluster_io definitions for use with io bufs */
159#define b_uploffset b_bufsize
160#define b_orig b_freelist.tqe_prev
161#define b_shadow b_freelist.tqe_next
162#define b_shadow_ref b_validoff
163#ifdef BUF_MAKE_PRIVATE
164#define b_data_ref b_validend
165#endif
166#define b_trans_head b_freelist.tqe_prev
167#define b_trans_next b_freelist.tqe_next
168#define b_iostate b_rcred
169#define b_cliodone b_wcred
170
171/*
172 * These flags are kept in b_lflags...
173 * buf_mtx must be held before examining/updating
174 */
175#define BL_BUSY 0x00000001 /* I/O in progress. */
176#define BL_WANTED 0x00000002 /* Process wants this buffer. */
177#define BL_IOBUF 0x00000004 /* buffer allocated via 'buf_alloc' */
178#define BL_WANTDEALLOC 0x00000010 /* buffer should be put on empty list when clean */
179#define BL_SHADOW 0x00000020
180#define BL_EXTERNAL 0x00000040
181#define BL_WAITSHADOW 0x00000080
182#define BL_IOBUF_ALLOC 0x00000100
183#define BL_WANTED_REF 0x00000200
184#define BL_IOBUF_VDEV 0x00000400 /* iobuf was for a diskimage */
185
186/*
187 * Parameters for buffer cache garbage collection
188 */
189#define BUF_STALE_THRESHHOLD 30 /* Collect if untouched in the last 30 seconds */
190#define BUF_MAX_GC_BATCH_SIZE 64 /* Under a single grab of the lock */
191
192/*
193 * mask used by buf_flags... these are the readable external flags
194 */
195#define BUF_X_RDFLAGS (B_PHYS | B_RAW | B_LOCKED | B_ASYNC | B_READ | B_WRITE | B_PAGEIO |\
196 B_META | B_CLUSTER | B_DELWRI | B_FUA | B_PASSIVE | B_IOSTREAMING |\
197 B_ENCRYPTED_IO | B_STATICCONTENT)
198/*
199 * mask used by buf_clearflags/buf_setflags... these are the writable external flags
200 */
201#define BUF_X_WRFLAGS (B_PHYS | B_RAW | B_LOCKED | B_ASYNC | B_READ | B_WRITE | B_PAGEIO |\
202 B_NOCACHE | B_FUA | B_PASSIVE | B_IOSTREAMING)
203
204#if 0
205/* b_flags defined in buf.h */
206#define B_WRITE 0x00000000 /* Write buffer (pseudo flag). */
207#define B_READ 0x00000001 /* Read buffer. */
208#define B_ASYNC 0x00000002 /* Start I/O, do not wait. */
209#define B_NOCACHE 0x00000004 /* Do not cache block after use. */
210#define B_DELWRI 0x00000008 /* Delay I/O until buffer reused. */
211#define B_LOCKED 0x00000010 /* Locked in core (not reusable). */
212#define B_PHYS 0x00000020 /* I/O to user memory. */
213#define B_CLUSTER 0x00000040 /* UPL based I/O generated by cluster layer */
214#define B_PAGEIO 0x00000080 /* Page in/out */
215#define B_META 0x00000100 /* buffer contains meta-data. */
216#define B_RAW 0x00000200 /* Set by physio for raw transfers. */
217#define B_FUA 0x00000400 /* Write-through disk cache(if supported) */
218#define B_PASSIVE 0x00000800 /* PASSIVE I/Os are ignored by THROTTLE I/O */
219#define B_IOSTREAMING 0x00001000 /* sequential access pattern detected */
220#define B_ENCRYPTED_IO 0x00004000 /* Encrypted I/O */
221#define B_STATICCONTENT 0x00008000 /* Buffer is likely to remain unaltered */
222#endif
223
224/*
225 * These flags are kept in b_flags... access is lockless
226 * External flags are defined in buf.h and cannot overlap
227 * the internal flags
228 *
229 * these flags are internal... there definition may change
230 */
231#define B_CACHE 0x00010000 /* getblk found us in the cache. */
232#define B_DONE 0x00020000 /* I/O completed. */
233#define B_INVAL 0x00040000 /* Does not contain valid info. */
234#define B_ERROR 0x00080000 /* I/O error occurred. */
235#define B_EINTR 0x00100000 /* I/O was interrupted */
236#define B_AGE 0x00200000 /* Move to age queue when I/O done. */
237#define B_FILTER 0x00400000 /* call b_iodone from biodone as an in-line filter */
238#define B_CALL 0x00800000 /* Call b_iodone from biodone, assumes b_iodone consumes bp */
239#define B_EOT 0x01000000 /* last buffer in a transaction list created by cluster_io */
240#define B_WASDIRTY 0x02000000 /* page was found dirty in the VM cache */
241#define B_HDRALLOC 0x04000000 /* zone allocated buffer header */
242#define B_ZALLOC 0x08000000 /* b_datap is zalloc()ed */
243/*
244 * private flags used by by the cluster layer
245 */
246#define B_COMMIT_UPL 0x40000000 /* commit/abort the UPL on I/O success/failure */
247#define B_TDONE 0x80000000 /* buf_t that is part of a cluster level transaction has completed */
248
249/* Flags to low-level allocation routines. */
250#define B_CLRBUF 0x01 /* Request allocated buffer be cleared. */
251#define B_SYNC 0x02 /* Do all allocations synchronously. */
252#define B_NOBUFF 0x04 /* Do not allocate struct buf */
253
254/*
255 * ba_flags (Buffer Attribute flags)
256 * Some of these may be in-use only on embedded devices.
257 */
258#define BA_RAW_ENCRYPTED_IO 0x00000001
259#define BA_THROTTLED_IO 0x00000002
260#define BA_DELAYIDLESLEEP 0x00000004 /* Process is marked to delay idle sleep on disk IO */
261#define BA_NOCACHE 0x00000008
262#define BA_META 0x00000010
263#define BA_GREEDY_MODE 0x00000020 /* High speed writes that consume more storage */
264#define BA_QUICK_COMPLETE 0x00000040 /* Request quick completion at expense of storage efficiency */
265#define BA_PASSIVE 0x00000080
266
267/*
268 * Note: IO_TIERs consume 0x0100, 0x0200, 0x0400, 0x0800
269 * These are now in-use by the I/O tiering system.
270 */
271#define BA_IO_TIER_MASK 0x00000f00
272#define BA_IO_TIER_SHIFT 8
273
274#define BA_ISOCHRONOUS 0x00001000 /* device specific isochronous throughput to media */
275
276#define BA_STRATEGY_TRACKED_IO 0x00002000 /* tracked by spec_strategy */
277#define BA_IO_TIER_UPGRADE 0x00004000 /* effective I/O tier is higher than BA_IO_TIER */
278#define BA_IO_SCHEDULED 0x00008000 /* buf is associated with a mount point that is io scheduled */
279#define BA_EXPEDITED_META_IO 0x00010000 /* metadata I/O which needs a high I/O tier */
280#define BA_WILL_VERIFY 0x00020000 /* Cluster layer will verify data */
281
282#define GET_BUFATTR_IO_TIER(bap) ((bap->ba_flags & BA_IO_TIER_MASK) >> BA_IO_TIER_SHIFT)
283#define SET_BUFATTR_IO_TIER(bap, tier) \
284do { \
285 (bap)->ba_flags &= (~BA_IO_TIER_MASK); \
286 (bap)->ba_flags |= (((tier) << BA_IO_TIER_SHIFT) & BA_IO_TIER_MASK); \
287} while(0)
288
289extern int niobuf_headers; /* The number of IO buffer headers for cluster IO */
290extern int nbuf_headers; /* The number of buffer headers */
291extern int max_nbuf_headers; /* The max number of buffer headers */
292extern int nbuf_hashelements; /* The number of elements in bufhash */
293extern struct buf *buf_headers; /* The buffer headers. */
294
295
296/*
297 * Definitions for the buffer free lists.
298 */
299
300enum bq_opts {
301 BQ_LOCKED = 0, /* super-blocks &c */
302 BQ_LRU = 1, /* lru, useful buffers */
303 BQ_AGE = 2, /* rubbish */
304 BQ_EMPTY = 3, /* buffer headers with no memory */
305 BQ_META = 4, /* buffer containing metadata */
306 BQ_LAUNDRY = 5, /* buffers that need cleaning */
307 BQUEUES = 6 /* number of free buffer queues */
308};
309
310#define CLUSTER_IO_BLOCK_SIZE 0x1000
311
312__BEGIN_DECLS
313
314buf_t alloc_io_buf(vnode_t, int);
315void free_io_buf(buf_t);
316
317int allocbuf(struct buf *, int);
318void bufinit(void);
319
320void buf_list_lock(void);
321void buf_list_unlock(void);
322
323void cluster_init(void);
324
325uint32_t count_busy_buffers(void);
326
327int buf_flushdirtyblks_skipinfo(vnode_t, int, int, const char *);
328void buf_wait_for_shadow_io(vnode_t, daddr64_t);
329
330#ifdef BUF_MAKE_PRIVATE
331errno_t buf_make_private(buf_t bp);
332#endif
333
334#ifdef CONFIG_PROTECT
335void buf_setcpoff(buf_t, uint64_t);
336#endif
337
338vnode_t buf_vnop_vnode(buf_t);
339
340__END_DECLS
341
342
343/*
344 * Stats on usefulness of the buffer cache
345 */
346struct bufstats {
347 long bufs_incore; /* found incore */
348 long bufs_busyincore; /* found incore. was busy */
349 long bufs_vmhits; /* not incore. found in VM */
350 long bufs_miss; /* not incore. not in VM */
351 long bufs_sleeps; /* buffer starvation */
352 long bufs_eblk; /* Calls to geteblk */
353 uint32_t bufs_iobufmax; /* Max. number of IO buffers used */
354 uint32_t bufs_iobufinuse; /* number of IO buffers in use */
355 long bufs_iobufsleeps; /* IO buffer starvation */
356 long bufs_iobufinuse_vdev; /* number of IO buffers in use by
357 * diskimages */
358};
359
360#endif /* KERNEL */
361#endif /* !_SYS_BUF_H_ */
362