xref: /titanic_41/usr/src/uts/common/os/bp_map.c (revision 749f21d359d8fbd020c974a1a5227316221bfc9c)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License, Version 1.0 only
6  * (the "License").  You may not use this file except in compliance
7  * with the License.
8  *
9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10  * or http://www.opensolaris.org/os/licensing.
11  * See the License for the specific language governing permissions
12  * and limitations under the License.
13  *
14  * When distributing Covered Code, include this CDDL HEADER in each
15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16  * If applicable, add the following below this CDDL HEADER, with the
17  * fields enclosed by brackets "[]" replaced with your own identifying
18  * information: Portions Copyright [yyyy] [name of copyright owner]
19  *
20  * CDDL HEADER END
21  */
22 /*
23  * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 #pragma ident	"%Z%%M%	%I%	%E% SMI"
28 
29 #include <sys/types.h>
30 #include <sys/sysmacros.h>
31 #include <sys/systm.h>
32 #include <sys/mman.h>
33 #include <sys/buf.h>
34 #include <sys/vmem.h>
35 #include <sys/cmn_err.h>
36 #include <sys/debug.h>
37 #include <sys/machparam.h>
38 #include <vm/page.h>
39 #include <vm/seg_kmem.h>
40 #include <vm/seg_kpm.h>
41 
42 #ifdef __sparc
43 #include <sys/cpu_module.h>
44 #define	BP_FLUSH(addr, size)	flush_instr_mem((void *)addr, size);
45 #else
46 #define	BP_FLUSH(addr, size)
47 #endif
48 
49 static vmem_t *bp_map_arena;
50 static size_t bp_align;
51 static uint_t bp_devload_flags = PROT_READ | PROT_WRITE | HAT_NOSYNC;
52 int	bp_max_cache = 1 << 17;		/* 128K default; tunable */
53 int	bp_mapin_kpm_enable = 1;	/* enable default; tunable */
54 
55 static void *
56 bp_vmem_alloc(vmem_t *vmp, size_t size, int vmflag)
57 {
58 	return (vmem_xalloc(vmp, size, bp_align, 0, 0, NULL, NULL, vmflag));
59 }
60 
61 void
62 bp_init(size_t align, uint_t devload_flags)
63 {
64 	bp_align = MAX(align, PAGESIZE);
65 	bp_devload_flags |= devload_flags;
66 
67 	if (bp_align <= bp_max_cache)
68 		bp_map_arena = vmem_create("bp_map", NULL, 0, bp_align,
69 		    bp_vmem_alloc, vmem_free, heap_arena,
70 		    MIN(8 * bp_align, bp_max_cache), VM_SLEEP);
71 }
72 
73 /*
74  * common routine so can be called with/without VM_SLEEP
75  */
76 void *
77 bp_mapin_common(struct buf *bp, int flag)
78 {
79 	struct as	*as;
80 	pfn_t		pfnum;
81 	page_t		*pp;
82 	page_t		**pplist;
83 	caddr_t		kaddr;
84 	caddr_t		addr;
85 	uintptr_t	off;
86 	size_t		size;
87 	pgcnt_t		npages;
88 	int		color;
89 
90 	/* return if already mapped in, no pageio/physio, or physio to kas */
91 	if ((bp->b_flags & B_REMAPPED) ||
92 	    !(bp->b_flags & (B_PAGEIO | B_PHYS)) ||
93 	    (((bp->b_flags & (B_PAGEIO | B_PHYS)) == B_PHYS) &&
94 	    ((bp->b_proc == NULL) || (bp->b_proc->p_as == &kas))))
95 		return (bp->b_un.b_addr);
96 
97 	ASSERT((bp->b_flags & (B_PAGEIO | B_PHYS)) != (B_PAGEIO | B_PHYS));
98 
99 	addr = (caddr_t)bp->b_un.b_addr;
100 	off = (uintptr_t)addr & PAGEOFFSET;
101 	size = P2ROUNDUP(bp->b_bcount + off, PAGESIZE);
102 	npages = btop(size);
103 
104 	/* Fastpath single page IO to locked memory by using kpm. */
105 	if ((bp->b_flags & (B_SHADOW | B_PAGEIO)) && (npages == 1) &&
106 	    kpm_enable && bp_mapin_kpm_enable) {
107 		if (bp->b_flags & B_SHADOW)
108 			pp = *bp->b_shadow;
109 		else
110 			pp = bp->b_pages;
111 		kaddr = hat_kpm_mapin(pp, NULL);
112 		bp->b_un.b_addr = kaddr + off;
113 		bp->b_flags |= B_REMAPPED;
114 		return (bp->b_un.b_addr);
115 	}
116 
117 	/*
118 	 * Allocate kernel virtual space for remapping.
119 	 */
120 	color = bp_color(bp);
121 	ASSERT(color < bp_align);
122 
123 	if (bp_map_arena != NULL) {
124 		kaddr = (caddr_t)vmem_alloc(bp_map_arena,
125 		    P2ROUNDUP(color + size, bp_align), flag);
126 		if (kaddr == NULL)
127 			return (NULL);
128 		kaddr += color;
129 	} else {
130 		kaddr = vmem_xalloc(heap_arena, size, bp_align, color,
131 		    0, NULL, NULL, flag);
132 		if (kaddr == NULL)
133 			return (NULL);
134 	}
135 
136 	ASSERT(P2PHASE((uintptr_t)kaddr, bp_align) == color);
137 
138 	/*
139 	 * Map bp into the virtual space we just allocated.
140 	 */
141 	if (bp->b_flags & B_PAGEIO) {
142 		pp = bp->b_pages;
143 		pplist = NULL;
144 	} else if (bp->b_flags & B_SHADOW) {
145 		pp = NULL;
146 		pplist = bp->b_shadow;
147 	} else {
148 		pp = NULL;
149 		pplist = NULL;
150 		if (bp->b_proc == NULL || (as = bp->b_proc->p_as) == NULL)
151 			as = &kas;
152 	}
153 
154 	bp->b_flags |= B_REMAPPED;
155 	bp->b_un.b_addr = kaddr + off;
156 
157 	while (npages-- != 0) {
158 		if (pp) {
159 			pfnum = pp->p_pagenum;
160 			pp = pp->p_next;
161 		} else if (pplist == NULL) {
162 			pfnum = hat_getpfnum(as->a_hat,
163 			    (caddr_t)((uintptr_t)addr & MMU_PAGEMASK));
164 			if (pfnum == PFN_INVALID)
165 				panic("bp_mapin_common: hat_getpfnum for"
166 				    " addr %p failed\n", (void *)addr);
167 			addr += PAGESIZE;
168 		} else {
169 			pfnum = (*pplist)->p_pagenum;
170 			pplist++;
171 		}
172 
173 		hat_devload(kas.a_hat, kaddr, PAGESIZE, pfnum,
174 		    bp_devload_flags, HAT_LOAD_LOCK);
175 
176 		kaddr += PAGESIZE;
177 	}
178 	return (bp->b_un.b_addr);
179 }
180 
181 /*
182  * Convert bp for pageio/physio to a kernel addressable location.
183  */
184 void
185 bp_mapin(struct buf *bp)
186 {
187 	(void) bp_mapin_common(bp, VM_SLEEP);
188 }
189 
190 /*
191  * Release all the resources associated with a previous bp_mapin() call.
192  */
193 void
194 bp_mapout(struct buf *bp)
195 {
196 	caddr_t		addr;
197 	uintptr_t	off;
198 	uintptr_t	base;
199 	uintptr_t	color;
200 	size_t		size;
201 	pgcnt_t		npages;
202 	page_t		*pp;
203 
204 	if ((bp->b_flags & B_REMAPPED) == 0)
205 		return;
206 
207 	addr = bp->b_un.b_addr;
208 	off = (uintptr_t)addr & PAGEOFFSET;
209 	size = P2ROUNDUP(bp->b_bcount + off, PAGESIZE);
210 	npages = btop(size);
211 
212 	bp->b_un.b_addr = (caddr_t)off;		/* debugging aid */
213 
214 	if ((bp->b_flags & (B_SHADOW | B_PAGEIO)) && (npages == 1) &&
215 	    kpm_enable && bp_mapin_kpm_enable) {
216 		if (bp->b_flags & B_SHADOW)
217 			pp = *bp->b_shadow;
218 		else
219 			pp = bp->b_pages;
220 		hat_kpm_mapout(pp, NULL, addr);
221 		bp->b_flags &= ~B_REMAPPED;
222 		return;
223 	}
224 
225 	base = (uintptr_t)addr & MMU_PAGEMASK;
226 	BP_FLUSH(base, size);
227 	hat_unload(kas.a_hat, (void *)base, size,
228 	    HAT_UNLOAD_NOSYNC | HAT_UNLOAD_UNLOCK);
229 	if (bp_map_arena != NULL) {
230 		color = P2PHASE(base, bp_align);
231 		vmem_free(bp_map_arena, (void *)(base - color),
232 		    P2ROUNDUP(color + size, bp_align));
233 	} else
234 		vmem_free(heap_arena, (void *)base, size);
235 	bp->b_flags &= ~B_REMAPPED;
236 }
237