2 * Copyright (c) 2014 Gleb Smirnoff <glebius@FreeBSD.org>
3 * Copyright (c) 2003-2004 Alan L. Cox <alc@cs.rice.edu>
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 #ifndef _SYS_SF_BUF_H_
31 #define _SYS_SF_BUF_H_
33 struct sfstat { /* sendfile statistics */
34 uint64_t sf_syscalls; /* times sendfile was called */
35 uint64_t sf_noiocnt; /* times sendfile didn't require I/O */
36 uint64_t sf_iocnt; /* times sendfile had to do disk I/O */
37 uint64_t sf_pages_read; /* pages read as part of a request */
38 uint64_t sf_pages_valid; /* pages were valid for a request */
39 uint64_t sf_rhpages_requested; /* readahead pages requested */
40 uint64_t sf_rhpages_read; /* readahead pages read */
41 uint64_t sf_busy; /* times aborted on a busy page */
42 uint64_t sf_allocfail; /* times sfbuf allocation failed */
43 uint64_t sf_allocwait; /* times sfbuf allocation had to wait */
44 uint64_t sf_pages_bogus; /* times bogus page was used */
48 #include <sys/types.h>
49 #include <sys/systm.h>
50 #include <sys/counter.h>
52 #include <vm/vm_param.h>
53 #include <vm/vm_page.h>
56 * Sf_bufs, or sendfile(2) buffers provide a vm_page that is mapped
57 * into kernel address space. Note, that they aren't used only
60 * Sf_bufs could be implemented as a feature of vm_page_t, but that
61 * would require growth of the structure. That's why they are implemented
62 * as a separate hash indexed by vm_page address. Implementation lives in
63 * kern/subr_sfbuf.c. Meanwhile, most 64-bit machines have a physical map,
64 * so they don't require this hash at all, thus ignore subr_sfbuf.c.
66 * Different 32-bit architectures demand different requirements on sf_buf
67 * hash and functions. They request features in machine/vmparam.h, which
68 * enable parts of this file. They can also optionally provide helpers in
72 * SFBUF This machine requires sf_buf hash.
73 * subr_sfbuf.c should be compiled.
74 * SFBUF_CPUSET This machine can perform SFB_CPUPRIVATE mappings,
75 * that do no invalidate cache on the rest of CPUs.
76 * SFBUF_NOMD This machine doesn't have machine/sf_buf.h
78 * SFBUF_OPTIONAL_DIRECT_MAP Value of this define is used as boolean
79 * variable that tells whether machine is
80 * capable of direct map or not at runtime.
81 * SFBUF_MAP This machine provides its own sf_buf_map() and
83 * SFBUF_PROCESS_PAGE This machine provides sf_buf_process_page()
88 #if defined(SMP) && defined(SFBUF_CPUSET)
89 #include <sys/_cpuset.h>
91 #include <sys/queue.h>
94 LIST_ENTRY(sf_buf) list_entry; /* list of buffers */
95 TAILQ_ENTRY(sf_buf) free_entry; /* list of buffers */
96 vm_page_t m; /* currently mapped page */
97 vm_offset_t kva; /* va of mapping */
98 int ref_count; /* usage of this mapping */
99 #if defined(SMP) && defined(SFBUF_CPUSET)
100 cpuset_t cpumask; /* where mapping is valid */
108 #include <machine/sf_buf.h>
110 #ifdef SFBUF_OPTIONAL_DIRECT_MAP
111 #include <machine/md_var.h>
115 struct sf_buf *sf_buf_alloc(struct vm_page *, int);
116 void sf_buf_free(struct sf_buf *);
117 void sf_buf_ref(struct sf_buf *);
119 static inline vm_offset_t
120 sf_buf_kva(struct sf_buf *sf)
122 #ifdef SFBUF_OPTIONAL_DIRECT_MAP
123 if (SFBUF_OPTIONAL_DIRECT_MAP)
124 return (SFBUF_PHYS_DMAP(VM_PAGE_TO_PHYS((vm_page_t)sf)));
130 static inline vm_page_t
131 sf_buf_page(struct sf_buf *sf)
133 #ifdef SFBUF_OPTIONAL_DIRECT_MAP
134 if (SFBUF_OPTIONAL_DIRECT_MAP)
135 return ((vm_page_t)sf);
145 sf_buf_map(struct sf_buf *sf, int flags)
148 pmap_qenter(sf->kva, &sf->m, 1);
152 sf_buf_unmap(struct sf_buf *sf)
157 #endif /* SFBUF_MAP */
159 #if defined(SMP) && defined(SFBUF_CPUSET)
160 void sf_buf_shootdown(struct sf_buf *, int);
163 #ifdef SFBUF_PROCESS_PAGE
164 boolean_t sf_buf_process_page(vm_page_t, void (*)(struct sf_buf *));
169 static inline struct sf_buf *
170 sf_buf_alloc(struct vm_page *m, int pri)
173 return ((struct sf_buf *)m);
177 sf_buf_free(struct sf_buf *sf)
182 sf_buf_ref(struct sf_buf *sf)
188 * Options to sf_buf_alloc() are specified through its flags argument. This
189 * argument's value should be the result of a bitwise or'ing of one or more
190 * of the following values.
192 #define SFB_CATCH 1 /* Check signals if the allocation
194 #define SFB_CPUPRIVATE 2 /* Create a CPU private mapping. */
195 #define SFB_DEFAULT 0
196 #define SFB_NOWAIT 4 /* Return NULL if all bufs are used. */
198 extern counter_u64_t sfstat[sizeof(struct sfstat) / sizeof(uint64_t)];
199 #define SFSTAT_ADD(name, val) \
200 counter_u64_add(sfstat[offsetof(struct sfstat, name) / sizeof(uint64_t)],\
202 #define SFSTAT_INC(name) SFSTAT_ADD(name, 1)
204 #endif /* !_SYS_SF_BUF_H_ */