diff options
author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /arch/sparc64/kernel/iommu_common.c |
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'arch/sparc64/kernel/iommu_common.c')
-rw-r--r-- | arch/sparc64/kernel/iommu_common.c | 231 |
1 files changed, 231 insertions, 0 deletions
diff --git a/arch/sparc64/kernel/iommu_common.c b/arch/sparc64/kernel/iommu_common.c new file mode 100644 index 000000000000..12c93a3eee26 --- /dev/null +++ b/arch/sparc64/kernel/iommu_common.c | |||
@@ -0,0 +1,231 @@ | |||
1 | /* $Id: iommu_common.c,v 1.9 2001/12/17 07:05:09 davem Exp $ | ||
2 | * iommu_common.c: UltraSparc SBUS/PCI common iommu code. | ||
3 | * | ||
4 | * Copyright (C) 1999 David S. Miller (davem@redhat.com) | ||
5 | */ | ||
6 | |||
7 | #include "iommu_common.h" | ||
8 | |||
9 | /* You are _strongly_ advised to enable the following debugging code | ||
10 | * any time you make changes to the sg code below, run it for a while | ||
11 | * with filesystems mounted read-only before buying the farm... -DaveM | ||
12 | */ | ||
13 | |||
14 | #ifdef VERIFY_SG | ||
15 | static int verify_lengths(struct scatterlist *sg, int nents, int npages) | ||
16 | { | ||
17 | int sg_len, dma_len; | ||
18 | int i, pgcount; | ||
19 | |||
20 | sg_len = 0; | ||
21 | for (i = 0; i < nents; i++) | ||
22 | sg_len += sg[i].length; | ||
23 | |||
24 | dma_len = 0; | ||
25 | for (i = 0; i < nents && sg[i].dma_length; i++) | ||
26 | dma_len += sg[i].dma_length; | ||
27 | |||
28 | if (sg_len != dma_len) { | ||
29 | printk("verify_lengths: Error, different, sg[%d] dma[%d]\n", | ||
30 | sg_len, dma_len); | ||
31 | return -1; | ||
32 | } | ||
33 | |||
34 | pgcount = 0; | ||
35 | for (i = 0; i < nents && sg[i].dma_length; i++) { | ||
36 | unsigned long start, end; | ||
37 | |||
38 | start = sg[i].dma_address; | ||
39 | start = start & IO_PAGE_MASK; | ||
40 | |||
41 | end = sg[i].dma_address + sg[i].dma_length; | ||
42 | end = (end + (IO_PAGE_SIZE - 1)) & IO_PAGE_MASK; | ||
43 | |||
44 | pgcount += ((end - start) >> IO_PAGE_SHIFT); | ||
45 | } | ||
46 | |||
47 | if (pgcount != npages) { | ||
48 | printk("verify_lengths: Error, page count wrong, " | ||
49 | "npages[%d] pgcount[%d]\n", | ||
50 | npages, pgcount); | ||
51 | return -1; | ||
52 | } | ||
53 | |||
54 | /* This test passes... */ | ||
55 | return 0; | ||
56 | } | ||
57 | |||
58 | static int verify_one_map(struct scatterlist *dma_sg, struct scatterlist **__sg, int nents, iopte_t **__iopte) | ||
59 | { | ||
60 | struct scatterlist *sg = *__sg; | ||
61 | iopte_t *iopte = *__iopte; | ||
62 | u32 dlen = dma_sg->dma_length; | ||
63 | u32 daddr; | ||
64 | unsigned int sglen; | ||
65 | unsigned long sgaddr; | ||
66 | |||
67 | daddr = dma_sg->dma_address; | ||
68 | sglen = sg->length; | ||
69 | sgaddr = (unsigned long) (page_address(sg->page) + sg->offset); | ||
70 | while (dlen > 0) { | ||
71 | unsigned long paddr; | ||
72 | |||
73 | /* SG and DMA_SG must begin at the same sub-page boundary. */ | ||
74 | if ((sgaddr & ~IO_PAGE_MASK) != (daddr & ~IO_PAGE_MASK)) { | ||
75 | printk("verify_one_map: Wrong start offset " | ||
76 | "sg[%08lx] dma[%08x]\n", | ||
77 | sgaddr, daddr); | ||
78 | nents = -1; | ||
79 | goto out; | ||
80 | } | ||
81 | |||
82 | /* Verify the IOPTE points to the right page. */ | ||
83 | paddr = iopte_val(*iopte) & IOPTE_PAGE; | ||
84 | if ((paddr + PAGE_OFFSET) != (sgaddr & IO_PAGE_MASK)) { | ||
85 | printk("verify_one_map: IOPTE[%08lx] maps the " | ||
86 | "wrong page, should be [%08lx]\n", | ||
87 | iopte_val(*iopte), (sgaddr & IO_PAGE_MASK) - PAGE_OFFSET); | ||
88 | nents = -1; | ||
89 | goto out; | ||
90 | } | ||
91 | |||
92 | /* If this SG crosses a page, adjust to that next page | ||
93 | * boundary and loop. | ||
94 | */ | ||
95 | if ((sgaddr & IO_PAGE_MASK) ^ ((sgaddr + sglen - 1) & IO_PAGE_MASK)) { | ||
96 | unsigned long next_page, diff; | ||
97 | |||
98 | next_page = (sgaddr + IO_PAGE_SIZE) & IO_PAGE_MASK; | ||
99 | diff = next_page - sgaddr; | ||
100 | sgaddr += diff; | ||
101 | daddr += diff; | ||
102 | sglen -= diff; | ||
103 | dlen -= diff; | ||
104 | if (dlen > 0) | ||
105 | iopte++; | ||
106 | continue; | ||
107 | } | ||
108 | |||
109 | /* SG wholly consumed within this page. */ | ||
110 | daddr += sglen; | ||
111 | dlen -= sglen; | ||
112 | |||
113 | if (dlen > 0 && ((daddr & ~IO_PAGE_MASK) == 0)) | ||
114 | iopte++; | ||
115 | |||
116 | sg++; | ||
117 | if (--nents <= 0) | ||
118 | break; | ||
119 | sgaddr = (unsigned long) (page_address(sg->page) + sg->offset); | ||
120 | sglen = sg->length; | ||
121 | } | ||
122 | if (dlen < 0) { | ||
123 | /* Transfer overrun, big problems. */ | ||
124 | printk("verify_one_map: Transfer overrun by %d bytes.\n", | ||
125 | -dlen); | ||
126 | nents = -1; | ||
127 | } else { | ||
128 | /* Advance to next dma_sg implies that the next iopte will | ||
129 | * begin it. | ||
130 | */ | ||
131 | iopte++; | ||
132 | } | ||
133 | |||
134 | out: | ||
135 | *__sg = sg; | ||
136 | *__iopte = iopte; | ||
137 | return nents; | ||
138 | } | ||
139 | |||
140 | static int verify_maps(struct scatterlist *sg, int nents, iopte_t *iopte) | ||
141 | { | ||
142 | struct scatterlist *dma_sg = sg; | ||
143 | struct scatterlist *orig_dma_sg = dma_sg; | ||
144 | int orig_nents = nents; | ||
145 | |||
146 | for (;;) { | ||
147 | nents = verify_one_map(dma_sg, &sg, nents, &iopte); | ||
148 | if (nents <= 0) | ||
149 | break; | ||
150 | dma_sg++; | ||
151 | if (dma_sg->dma_length == 0) | ||
152 | break; | ||
153 | } | ||
154 | |||
155 | if (nents > 0) { | ||
156 | printk("verify_maps: dma maps consumed by some sgs remain (%d)\n", | ||
157 | nents); | ||
158 | return -1; | ||
159 | } | ||
160 | |||
161 | if (nents < 0) { | ||
162 | printk("verify_maps: Error, messed up mappings, " | ||
163 | "at sg %d dma_sg %d\n", | ||
164 | (int) (orig_nents + nents), (int) (dma_sg - orig_dma_sg)); | ||
165 | return -1; | ||
166 | } | ||
167 | |||
168 | /* This test passes... */ | ||
169 | return 0; | ||
170 | } | ||
171 | |||
172 | void verify_sglist(struct scatterlist *sg, int nents, iopte_t *iopte, int npages) | ||
173 | { | ||
174 | if (verify_lengths(sg, nents, npages) < 0 || | ||
175 | verify_maps(sg, nents, iopte) < 0) { | ||
176 | int i; | ||
177 | |||
178 | printk("verify_sglist: Crap, messed up mappings, dumping, iodma at "); | ||
179 | printk("%016lx.\n", sg->dma_address & IO_PAGE_MASK); | ||
180 | |||
181 | for (i = 0; i < nents; i++) { | ||
182 | printk("sg(%d): page_addr(%p) off(%x) length(%x) " | ||
183 | "dma_address[%016lx] dma_length[%016lx]\n", | ||
184 | i, | ||
185 | page_address(sg[i].page), sg[i].offset, | ||
186 | sg[i].length, | ||
187 | sg[i].dma_address, sg[i].dma_length); | ||
188 | } | ||
189 | } | ||
190 | |||
191 | /* Seems to be ok */ | ||
192 | } | ||
193 | #endif | ||
194 | |||
195 | unsigned long prepare_sg(struct scatterlist *sg, int nents) | ||
196 | { | ||
197 | struct scatterlist *dma_sg = sg; | ||
198 | unsigned long prev; | ||
199 | u32 dent_addr, dent_len; | ||
200 | |||
201 | prev = (unsigned long) (page_address(sg->page) + sg->offset); | ||
202 | prev += (unsigned long) (dent_len = sg->length); | ||
203 | dent_addr = (u32) ((unsigned long)(page_address(sg->page) + sg->offset) | ||
204 | & (IO_PAGE_SIZE - 1UL)); | ||
205 | while (--nents) { | ||
206 | unsigned long addr; | ||
207 | |||
208 | sg++; | ||
209 | addr = (unsigned long) (page_address(sg->page) + sg->offset); | ||
210 | if (! VCONTIG(prev, addr)) { | ||
211 | dma_sg->dma_address = dent_addr; | ||
212 | dma_sg->dma_length = dent_len; | ||
213 | dma_sg++; | ||
214 | |||
215 | dent_addr = ((dent_addr + | ||
216 | dent_len + | ||
217 | (IO_PAGE_SIZE - 1UL)) >> IO_PAGE_SHIFT); | ||
218 | dent_addr <<= IO_PAGE_SHIFT; | ||
219 | dent_addr += addr & (IO_PAGE_SIZE - 1UL); | ||
220 | dent_len = 0; | ||
221 | } | ||
222 | dent_len += sg->length; | ||
223 | prev = addr + sg->length; | ||
224 | } | ||
225 | dma_sg->dma_address = dent_addr; | ||
226 | dma_sg->dma_length = dent_len; | ||
227 | |||
228 | return ((unsigned long) dent_addr + | ||
229 | (unsigned long) dent_len + | ||
230 | (IO_PAGE_SIZE - 1UL)) >> IO_PAGE_SHIFT; | ||
231 | } | ||