Annotation of sys/dev/usb/usb_mem.c, Revision 1.1.1.1
1.1 nbrk 1: /* $OpenBSD: usb_mem.c,v 1.20 2007/06/15 04:05:53 deraadt Exp $ */
2: /* $NetBSD: usb_mem.c,v 1.26 2003/02/01 06:23:40 thorpej Exp $ */
3:
4: /*
5: * Copyright (c) 1998 The NetBSD Foundation, Inc.
6: * All rights reserved.
7: *
8: * This code is derived from software contributed to The NetBSD Foundation
9: * by Lennart Augustsson (lennart@augustsson.net) at
10: * Carlstedt Research & Technology.
11: *
12: * Redistribution and use in source and binary forms, with or without
13: * modification, are permitted provided that the following conditions
14: * are met:
15: * 1. Redistributions of source code must retain the above copyright
16: * notice, this list of conditions and the following disclaimer.
17: * 2. Redistributions in binary form must reproduce the above copyright
18: * notice, this list of conditions and the following disclaimer in the
19: * documentation and/or other materials provided with the distribution.
20: * 3. All advertising materials mentioning features or use of this software
21: * must display the following acknowledgement:
22: * This product includes software developed by the NetBSD
23: * Foundation, Inc. and its contributors.
24: * 4. Neither the name of The NetBSD Foundation nor the names of its
25: * contributors may be used to endorse or promote products derived
26: * from this software without specific prior written permission.
27: *
28: * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
29: * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
30: * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
31: * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
32: * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
33: * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
34: * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
35: * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
36: * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
37: * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
38: * POSSIBILITY OF SUCH DAMAGE.
39: */
40:
41: /*
42: * USB DMA memory allocation.
43: * We need to allocate a lot of small (many 8 byte, some larger)
44: * memory blocks that can be used for DMA. Using the bus_dma
45: * routines directly would incur large overheads in space and time.
46: */
47:
48: #include <sys/param.h>
49: #include <sys/systm.h>
50: #include <sys/kernel.h>
51: #include <sys/malloc.h>
52: #include <sys/queue.h>
53: #include <sys/timeout.h>
54: #include <sys/device.h> /* for usbdivar.h */
55: #include <machine/bus.h>
56:
57: #ifdef DIAGNOSTIC
58: #include <sys/proc.h>
59: #endif
60:
61: #include <dev/usb/usb.h>
62: #include <dev/usb/usbdi.h>
63: #include <dev/usb/usbdivar.h> /* just for usb_dma_t */
64: #include <dev/usb/usb_mem.h>
65:
66: #ifdef USB_DEBUG
67: #define DPRINTF(x) do { if (usbdebug) printf x; } while (0)
68: #define DPRINTFN(n,x) do { if (usbdebug>(n)) printf x; } while (0)
69: extern int usbdebug;
70: #else
71: #define DPRINTF(x)
72: #define DPRINTFN(n,x)
73: #endif
74:
75: #define USB_MEM_SMALL 64
76: #define USB_MEM_CHUNKS 64
77: #define USB_MEM_BLOCK (USB_MEM_SMALL * USB_MEM_CHUNKS)
78:
79: /* This struct is overlayed on free fragments. */
80: struct usb_frag_dma {
81: usb_dma_block_t *block;
82: u_int offs;
83: LIST_ENTRY(usb_frag_dma) next;
84: };
85:
86: usbd_status usb_block_allocmem(bus_dma_tag_t, size_t, size_t,
87: usb_dma_block_t **);
88: void usb_block_freemem(usb_dma_block_t *);
89:
90: LIST_HEAD(, usb_dma_block) usb_blk_freelist =
91: LIST_HEAD_INITIALIZER(usb_blk_freelist);
92: int usb_blk_nfree = 0;
93: /* XXX should have different free list for different tags (for speed) */
94: LIST_HEAD(, usb_frag_dma) usb_frag_freelist =
95: LIST_HEAD_INITIALIZER(usb_frag_freelist);
96:
97: usbd_status
98: usb_block_allocmem(bus_dma_tag_t tag, size_t size, size_t align,
99: usb_dma_block_t **dmap)
100: {
101: int error;
102: usb_dma_block_t *p;
103: int s;
104:
105: DPRINTFN(5, ("usb_block_allocmem: size=%lu align=%lu\n",
106: (u_long)size, (u_long)align));
107:
108: #ifdef DIAGNOSTIC
109: if (!curproc) {
110: printf("usb_block_allocmem: in interrupt context, size=%lu\n",
111: (unsigned long) size);
112: }
113: #endif
114:
115: s = splusb();
116: /* First check the free list. */
117: for (p = LIST_FIRST(&usb_blk_freelist); p; p = LIST_NEXT(p, next)) {
118: if (p->tag == tag && p->size >= size && p->align >= align) {
119: LIST_REMOVE(p, next);
120: usb_blk_nfree--;
121: splx(s);
122: *dmap = p;
123: DPRINTFN(6,("usb_block_allocmem: free list size=%lu\n",
124: (u_long)p->size));
125: return (USBD_NORMAL_COMPLETION);
126: }
127: }
128: splx(s);
129:
130: #ifdef DIAGNOSTIC
131: if (!curproc) {
132: printf("usb_block_allocmem: in interrupt context, failed\n");
133: return (USBD_NOMEM);
134: }
135: #endif
136:
137: DPRINTFN(6, ("usb_block_allocmem: no free\n"));
138: p = malloc(sizeof *p, M_USB, M_NOWAIT);
139: if (p == NULL)
140: return (USBD_NOMEM);
141:
142: p->tag = tag;
143: p->size = size;
144: p->align = align;
145: error = bus_dmamem_alloc(tag, p->size, align, 0,
146: p->segs, sizeof(p->segs)/sizeof(p->segs[0]),
147: &p->nsegs, BUS_DMA_NOWAIT);
148: if (error)
149: goto free0;
150:
151: error = bus_dmamem_map(tag, p->segs, p->nsegs, p->size,
152: &p->kaddr, BUS_DMA_NOWAIT|BUS_DMA_COHERENT);
153: if (error)
154: goto free1;
155:
156: error = bus_dmamap_create(tag, p->size, 1, p->size,
157: 0, BUS_DMA_NOWAIT, &p->map);
158: if (error)
159: goto unmap;
160:
161: error = bus_dmamap_load(tag, p->map, p->kaddr, p->size, NULL,
162: BUS_DMA_NOWAIT);
163: if (error)
164: goto destroy;
165:
166: *dmap = p;
167: return (USBD_NORMAL_COMPLETION);
168:
169: destroy:
170: bus_dmamap_destroy(tag, p->map);
171: unmap:
172: bus_dmamem_unmap(tag, p->kaddr, p->size);
173: free1:
174: bus_dmamem_free(tag, p->segs, p->nsegs);
175: free0:
176: free(p, M_USB);
177: return (USBD_NOMEM);
178: }
179:
180: #if 0
181: void
182: usb_block_real_freemem(usb_dma_block_t *p)
183: {
184: #ifdef DIAGNOSTIC
185: if (!curproc) {
186: printf("usb_block_real_freemem: in interrupt context\n");
187: return;
188: }
189: #endif
190: bus_dmamap_unload(p->tag, p->map);
191: bus_dmamap_destroy(p->tag, p->map);
192: bus_dmamem_unmap(p->tag, p->kaddr, p->size);
193: bus_dmamem_free(p->tag, p->segs, p->nsegs);
194: free(p, M_USB);
195: }
196: #endif
197:
198: /*
199: * Do not free the memory unconditionally since we might be called
200: * from an interrupt context and that is BAD.
201: * XXX when should we really free?
202: */
203: void
204: usb_block_freemem(usb_dma_block_t *p)
205: {
206: int s;
207:
208: DPRINTFN(6, ("usb_block_freemem: size=%lu\n", (u_long)p->size));
209: s = splusb();
210: LIST_INSERT_HEAD(&usb_blk_freelist, p, next);
211: usb_blk_nfree++;
212: splx(s);
213: }
214:
215: usbd_status
216: usb_allocmem(usbd_bus_handle bus, size_t size, size_t align, usb_dma_t *p)
217: {
218: bus_dma_tag_t tag = bus->dmatag;
219: usbd_status err;
220: struct usb_frag_dma *f;
221: usb_dma_block_t *b;
222: int i;
223: int s;
224:
225: /* If the request is large then just use a full block. */
226: if (size > USB_MEM_SMALL || align > USB_MEM_SMALL) {
227: DPRINTFN(1, ("usb_allocmem: large alloc %d\n", (int)size));
228: size = (size + USB_MEM_BLOCK - 1) & ~(USB_MEM_BLOCK - 1);
229: err = usb_block_allocmem(tag, size, align, &p->block);
230: if (!err) {
231: p->block->fullblock = 1;
232: p->offs = 0;
233: }
234: return (err);
235: }
236:
237: s = splusb();
238: /* Check for free fragments. */
239: for (f = LIST_FIRST(&usb_frag_freelist); f; f = LIST_NEXT(f, next))
240: if (f->block->tag == tag)
241: break;
242: if (f == NULL) {
243: DPRINTFN(1, ("usb_allocmem: adding fragments\n"));
244: err = usb_block_allocmem(tag, USB_MEM_BLOCK, USB_MEM_SMALL,&b);
245: if (err) {
246: splx(s);
247: return (err);
248: }
249: b->fullblock = 0;
250: for (i = 0; i < USB_MEM_BLOCK; i += USB_MEM_SMALL) {
251: f = (struct usb_frag_dma *)(b->kaddr + i);
252: f->block = b;
253: f->offs = i;
254: LIST_INSERT_HEAD(&usb_frag_freelist, f, next);
255: }
256: f = LIST_FIRST(&usb_frag_freelist);
257: }
258: p->block = f->block;
259: p->offs = f->offs;
260: LIST_REMOVE(f, next);
261: splx(s);
262: DPRINTFN(5, ("usb_allocmem: use frag=%p size=%d\n", f, (int)size));
263: return (USBD_NORMAL_COMPLETION);
264: }
265:
266: void
267: usb_freemem(usbd_bus_handle bus, usb_dma_t *p)
268: {
269: struct usb_frag_dma *f;
270: int s;
271:
272: if (p->block->fullblock) {
273: DPRINTFN(1, ("usb_freemem: large free\n"));
274: usb_block_freemem(p->block);
275: return;
276: }
277: f = KERNADDR(p, 0);
278: f->block = p->block;
279: f->offs = p->offs;
280: s = splusb();
281: LIST_INSERT_HEAD(&usb_frag_freelist, f, next);
282: splx(s);
283: DPRINTFN(5, ("usb_freemem: frag=%p\n", f));
284: }
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