darling-xnu/bsd/sys/buf_internal.h
2023-05-16 21:41:14 -07:00

355 lines
15 KiB
C

/*
* Copyright (c) 2000-2014 Apple Inc. All rights reserved.
*
* @APPLE_OSREFERENCE_LICENSE_HEADER_START@
*
* This file contains Original Code and/or Modifications of Original Code
* as defined in and that are subject to the Apple Public Source License
* Version 2.0 (the 'License'). You may not use this file except in
* compliance with the License. The rights granted to you under the License
* may not be used to create, or enable the creation or redistribution of,
* unlawful or unlicensed copies of an Apple operating system, or to
* circumvent, violate, or enable the circumvention or violation of, any
* terms of an Apple operating system software license agreement.
*
* Please obtain a copy of the License at
* http://www.opensource.apple.com/apsl/ and read it before using this file.
*
* The Original Code and all software distributed under the License are
* distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
* Please see the License for the specific language governing rights and
* limitations under the License.
*
* @APPLE_OSREFERENCE_LICENSE_HEADER_END@
*/
/* Copyright (c) 1995 NeXT Computer, Inc. All Rights Reserved */
/*
* Copyright (c) 1982, 1986, 1989, 1993
* The Regents of the University of California. All rights reserved.
* (c) UNIX System Laboratories, Inc.
* All or some portions of this file are derived from material licensed
* to the University of California by American Telephone and Telegraph
* Co. or Unix System Laboratories, Inc. and are reproduced herein with
* the permission of UNIX System Laboratories, Inc.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* @(#)buf.h 8.9 (Berkeley) 3/30/95
*/
#ifndef _SYS_BUF_INTERNAL_H_
#define _SYS_BUF_INTERNAL_H_
#include <sys/appleapiopts.h>
#ifdef KERNEL
#include <sys/queue.h>
#include <sys/errno.h>
#include <sys/vm.h>
#include <sys/cdefs.h>
#include <sys/buf.h>
#include <sys/lock.h>
#if CONFIG_PROTECT
#include <sys/cprotect.h>
#endif
#define NOLIST ((struct buf *)0x87654321)
/*
* Attributes of an I/O to be used by lower layers
*/
struct bufattr {
#if CONFIG_PROTECT
struct cpx *ba_cpx;
uint64_t ba_cp_file_off;
#endif
uint64_t ba_flags; /* flags. Some are only in-use on embedded devices */
};
/*
* The buffer header describes an I/O operation in the kernel.
*/
struct buf {
LIST_ENTRY(buf) b_hash; /* Hash chain. */
LIST_ENTRY(buf) b_vnbufs; /* Buffer's associated vnode. */
TAILQ_ENTRY(buf) b_freelist; /* Free list position if not active. */
int b_timestamp; /* timestamp for queuing operation */
struct timeval b_timestamp_tv; /* microuptime for disk conditioner */
int b_whichq; /* the free list the buffer belongs to */
volatile uint32_t b_flags; /* B_* flags. */
volatile uint32_t b_lflags; /* BL_BUSY | BL_WANTED flags... protected by buf_mtx */
int b_error; /* errno value. */
int b_bufsize; /* Allocated buffer size. */
int b_bcount; /* Valid bytes in buffer. */
int b_resid; /* Remaining I/O. */
dev_t b_dev; /* Device associated with buffer. */
uintptr_t b_datap; /* Memory, superblocks, indirect etc.*/
daddr64_t b_lblkno; /* Logical block number. */
daddr64_t b_blkno; /* Underlying physical block number. */
void (*b_iodone)(buf_t, void *); /* Function to call upon completion. */
vnode_t b_vp; /* File vnode for data, device vnode for metadata. */
kauth_cred_t b_rcred; /* Read credentials reference. */
kauth_cred_t b_wcred; /* Write credentials reference. */
void * b_upl; /* Pointer to UPL */
buf_t b_real_bp; /* used to track bp generated through cluster_bp */
TAILQ_ENTRY(buf) b_act; /* Device driver queue when active */
void * b_drvdata; /* Device driver private use */
void * b_fsprivate; /* filesystem private use */
void * b_transaction; /* journal private use */
int b_dirtyoff; /* Offset in buffer of dirty region. */
int b_dirtyend; /* Offset of end of dirty region. */
int b_validoff; /* Offset in buffer of valid region. */
int b_validend; /* Offset of end of valid region. */
/* store extra information related to redundancy of data, such as
* which redundancy copy to use, etc
*/
uint32_t b_redundancy_flags;
proc_t b_proc; /* Associated proc; NULL if kernel. */
#ifdef BUF_MAKE_PRIVATE
buf_t b_data_store;
#endif
struct bufattr b_attr;
#ifdef JOE_DEBUG
void * b_owner;
int b_tag;
void * b_lastbrelse;
void * b_stackbrelse[6];
void * b_stackgetblk[6];
#endif
};
extern vm_offset_t buf_kernel_addrperm;
/* cluster_io definitions for use with io bufs */
#define b_uploffset b_bufsize
#define b_orig b_freelist.tqe_prev
#define b_shadow b_freelist.tqe_next
#define b_shadow_ref b_validoff
#ifdef BUF_MAKE_PRIVATE
#define b_data_ref b_validend
#endif
#define b_trans_head b_freelist.tqe_prev
#define b_trans_next b_freelist.tqe_next
#define b_iostate b_rcred
#define b_cliodone b_wcred
/*
* These flags are kept in b_lflags...
* buf_mtx must be held before examining/updating
*/
#define BL_BUSY 0x00000001 /* I/O in progress. */
#define BL_WANTED 0x00000002 /* Process wants this buffer. */
#define BL_IOBUF 0x00000004 /* buffer allocated via 'buf_alloc' */
#define BL_WANTDEALLOC 0x00000010 /* buffer should be put on empty list when clean */
#define BL_SHADOW 0x00000020
#define BL_EXTERNAL 0x00000040
#define BL_WAITSHADOW 0x00000080
#define BL_IOBUF_ALLOC 0x00000100
#define BL_WANTED_REF 0x00000200
#define BL_IOBUF_VDEV 0x00000400 /* iobuf was for a diskimage */
/*
* Parameters for buffer cache garbage collection
*/
#define BUF_STALE_THRESHHOLD 30 /* Collect if untouched in the last 30 seconds */
#define BUF_MAX_GC_BATCH_SIZE 64 /* Under a single grab of the lock */
/*
* mask used by buf_flags... these are the readable external flags
*/
#define BUF_X_RDFLAGS (B_PHYS | B_RAW | B_LOCKED | B_ASYNC | B_READ | B_WRITE | B_PAGEIO |\
B_META | B_CLUSTER | B_DELWRI | B_FUA | B_PASSIVE | B_IOSTREAMING |\
B_ENCRYPTED_IO | B_STATICCONTENT)
/*
* mask used by buf_clearflags/buf_setflags... these are the writable external flags
*/
#define BUF_X_WRFLAGS (B_PHYS | B_RAW | B_LOCKED | B_ASYNC | B_READ | B_WRITE | B_PAGEIO |\
B_NOCACHE | B_FUA | B_PASSIVE | B_IOSTREAMING)
#if 0
/* b_flags defined in buf.h */
#define B_WRITE 0x00000000 /* Write buffer (pseudo flag). */
#define B_READ 0x00000001 /* Read buffer. */
#define B_ASYNC 0x00000002 /* Start I/O, do not wait. */
#define B_NOCACHE 0x00000004 /* Do not cache block after use. */
#define B_DELWRI 0x00000008 /* Delay I/O until buffer reused. */
#define B_LOCKED 0x00000010 /* Locked in core (not reusable). */
#define B_PHYS 0x00000020 /* I/O to user memory. */
#define B_CLUSTER 0x00000040 /* UPL based I/O generated by cluster layer */
#define B_PAGEIO 0x00000080 /* Page in/out */
#define B_META 0x00000100 /* buffer contains meta-data. */
#define B_RAW 0x00000200 /* Set by physio for raw transfers. */
#define B_FUA 0x00000400 /* Write-through disk cache(if supported) */
#define B_PASSIVE 0x00000800 /* PASSIVE I/Os are ignored by THROTTLE I/O */
#define B_IOSTREAMING 0x00001000 /* sequential access pattern detected */
#define B_ENCRYPTED_IO 0x00004000 /* Encrypted I/O */
#define B_STATICCONTENT 0x00008000 /* Buffer is likely to remain unaltered */
#endif
/*
* These flags are kept in b_flags... access is lockless
* External flags are defined in buf.h and cannot overlap
* the internal flags
*
* these flags are internal... there definition may change
*/
#define B_CACHE 0x00010000 /* getblk found us in the cache. */
#define B_DONE 0x00020000 /* I/O completed. */
#define B_INVAL 0x00040000 /* Does not contain valid info. */
#define B_ERROR 0x00080000 /* I/O error occurred. */
#define B_EINTR 0x00100000 /* I/O was interrupted */
#define B_AGE 0x00200000 /* Move to age queue when I/O done. */
#define B_FILTER 0x00400000 /* call b_iodone from biodone as an in-line filter */
#define B_CALL 0x00800000 /* Call b_iodone from biodone, assumes b_iodone consumes bp */
#define B_EOT 0x01000000 /* last buffer in a transaction list created by cluster_io */
#define B_WASDIRTY 0x02000000 /* page was found dirty in the VM cache */
#define B_HDRALLOC 0x04000000 /* zone allocated buffer header */
#define B_ZALLOC 0x08000000 /* b_datap is zalloc()ed */
/*
* private flags used by by the cluster layer
*/
#define B_COMMIT_UPL 0x40000000 /* commit/abort the UPL on I/O success/failure */
#define B_TDONE 0x80000000 /* buf_t that is part of a cluster level transaction has completed */
/* Flags to low-level allocation routines. */
#define B_CLRBUF 0x01 /* Request allocated buffer be cleared. */
#define B_SYNC 0x02 /* Do all allocations synchronously. */
#define B_NOBUFF 0x04 /* Do not allocate struct buf */
/*
* ba_flags (Buffer Attribute flags)
* Some of these may be in-use only on embedded devices.
*/
#define BA_RAW_ENCRYPTED_IO 0x00000001
#define BA_THROTTLED_IO 0x00000002
#define BA_DELAYIDLESLEEP 0x00000004 /* Process is marked to delay idle sleep on disk IO */
#define BA_NOCACHE 0x00000008
#define BA_META 0x00000010
#define BA_GREEDY_MODE 0x00000020 /* High speed writes that consume more storage */
#define BA_QUICK_COMPLETE 0x00000040 /* Request quick completion at expense of storage efficiency */
#define BA_PASSIVE 0x00000080
/*
* Note: IO_TIERs consume 0x0100, 0x0200, 0x0400, 0x0800
* These are now in-use by the I/O tiering system.
*/
#define BA_IO_TIER_MASK 0x00000f00
#define BA_IO_TIER_SHIFT 8
#define BA_ISOCHRONOUS 0x00001000 /* device specific isochronous throughput to media */
#define BA_STRATEGY_TRACKED_IO 0x00002000 /* tracked by spec_strategy */
#define BA_IO_TIER_UPGRADE 0x00004000 /* effective I/O tier is higher than BA_IO_TIER */
#define BA_IO_SCHEDULED 0x00008000 /* buf is associated with a mount point that is io scheduled */
#define BA_EXPEDITED_META_IO 0x00010000 /* metadata I/O which needs a high I/O tier */
#define GET_BUFATTR_IO_TIER(bap) ((bap->ba_flags & BA_IO_TIER_MASK) >> BA_IO_TIER_SHIFT)
#define SET_BUFATTR_IO_TIER(bap, tier) \
do { \
(bap)->ba_flags &= (~BA_IO_TIER_MASK); \
(bap)->ba_flags |= (((tier) << BA_IO_TIER_SHIFT) & BA_IO_TIER_MASK); \
} while(0)
extern int niobuf_headers; /* The number of IO buffer headers for cluster IO */
extern int nbuf_headers; /* The number of buffer headers */
extern int max_nbuf_headers; /* The max number of buffer headers */
extern int nbuf_hashelements; /* The number of elements in bufhash */
extern struct buf *buf_headers; /* The buffer headers. */
/*
* Definitions for the buffer free lists.
*/
enum bq_opts {
BQ_LOCKED = 0, /* super-blocks &c */
BQ_LRU = 1, /* lru, useful buffers */
BQ_AGE = 2, /* rubbish */
BQ_EMPTY = 3, /* buffer headers with no memory */
BQ_META = 4, /* buffer containing metadata */
BQ_LAUNDRY = 5, /* buffers that need cleaning */
BQUEUES = 6 /* number of free buffer queues */
};
__BEGIN_DECLS
buf_t alloc_io_buf(vnode_t, int);
void free_io_buf(buf_t);
int allocbuf(struct buf *, int);
void bufinit(void);
void buf_list_lock(void);
void buf_list_unlock(void);
void cluster_init(void);
uint32_t count_busy_buffers(void);
int buf_flushdirtyblks_skipinfo(vnode_t, int, int, const char *);
void buf_wait_for_shadow_io(vnode_t, daddr64_t);
#ifdef BUF_MAKE_PRIVATE
errno_t buf_make_private(buf_t bp);
#endif
#ifdef CONFIG_PROTECT
void buf_setcpoff(buf_t, uint64_t);
#endif
__END_DECLS
/*
* Stats on usefulness of the buffer cache
*/
struct bufstats {
long bufs_incore; /* found incore */
long bufs_busyincore; /* found incore. was busy */
long bufs_vmhits; /* not incore. found in VM */
long bufs_miss; /* not incore. not in VM */
long bufs_sleeps; /* buffer starvation */
long bufs_eblk; /* Calls to geteblk */
uint32_t bufs_iobufmax; /* Max. number of IO buffers used */
uint32_t bufs_iobufinuse; /* number of IO buffers in use */
long bufs_iobufsleeps; /* IO buffer starvation */
long bufs_iobufinuse_vdev; /* number of IO buffers in use by
* diskimages */
};
#endif /* KERNEL */
#endif /* !_SYS_BUF_H_ */