xref: /openbmc/linux/drivers/misc/sgi-gru/grukdump.c (revision 176f011b)
1 /*
2  * SN Platform GRU Driver
3  *
4  *            Dump GRU State
5  *
6  *  Copyright (c) 2008 Silicon Graphics, Inc.  All Rights Reserved.
7  *
8  *  This program is free software; you can redistribute it and/or modify
9  *  it under the terms of the GNU General Public License as published by
10  *  the Free Software Foundation; either version 2 of the License, or
11  *  (at your option) any later version.
12  *
13  *  This program is distributed in the hope that it will be useful,
14  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
15  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16  *  GNU General Public License for more details.
17  *
18  *  You should have received a copy of the GNU General Public License
19  *  along with this program; if not, write to the Free Software
20  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
21  */
22 
23 #include <linux/kernel.h>
24 #include <linux/mm.h>
25 #include <linux/spinlock.h>
26 #include <linux/uaccess.h>
27 #include <linux/delay.h>
28 #include <linux/bitops.h>
29 #include <asm/uv/uv_hub.h>
30 
31 #include <linux/nospec.h>
32 
33 #include "gru.h"
34 #include "grutables.h"
35 #include "gruhandles.h"
36 #include "grulib.h"
37 
38 #define CCH_LOCK_ATTEMPTS	10
39 
40 static int gru_user_copy_handle(void __user **dp, void *s)
41 {
42 	if (copy_to_user(*dp, s, GRU_HANDLE_BYTES))
43 		return -1;
44 	*dp += GRU_HANDLE_BYTES;
45 	return 0;
46 }
47 
48 static int gru_dump_context_data(void *grubase,
49 			struct gru_context_configuration_handle *cch,
50 			void __user *ubuf, int ctxnum, int dsrcnt,
51 			int flush_cbrs)
52 {
53 	void *cb, *cbe, *tfh, *gseg;
54 	int i, scr;
55 
56 	gseg = grubase + ctxnum * GRU_GSEG_STRIDE;
57 	cb = gseg + GRU_CB_BASE;
58 	cbe = grubase + GRU_CBE_BASE;
59 	tfh = grubase + GRU_TFH_BASE;
60 
61 	for_each_cbr_in_allocation_map(i, &cch->cbr_allocation_map, scr) {
62 		if (flush_cbrs)
63 			gru_flush_cache(cb);
64 		if (gru_user_copy_handle(&ubuf, cb))
65 			goto fail;
66 		if (gru_user_copy_handle(&ubuf, tfh + i * GRU_HANDLE_STRIDE))
67 			goto fail;
68 		if (gru_user_copy_handle(&ubuf, cbe + i * GRU_HANDLE_STRIDE))
69 			goto fail;
70 		cb += GRU_HANDLE_STRIDE;
71 	}
72 	if (dsrcnt)
73 		memcpy(ubuf, gseg + GRU_DS_BASE, dsrcnt * GRU_HANDLE_STRIDE);
74 	return 0;
75 
76 fail:
77 	return -EFAULT;
78 }
79 
80 static int gru_dump_tfm(struct gru_state *gru,
81 		void __user *ubuf, void __user *ubufend)
82 {
83 	struct gru_tlb_fault_map *tfm;
84 	int i;
85 
86 	if (GRU_NUM_TFM * GRU_CACHE_LINE_BYTES > ubufend - ubuf)
87 		return -EFBIG;
88 
89 	for (i = 0; i < GRU_NUM_TFM; i++) {
90 		tfm = get_tfm(gru->gs_gru_base_vaddr, i);
91 		if (gru_user_copy_handle(&ubuf, tfm))
92 			goto fail;
93 	}
94 	return GRU_NUM_TFM * GRU_CACHE_LINE_BYTES;
95 
96 fail:
97 	return -EFAULT;
98 }
99 
100 static int gru_dump_tgh(struct gru_state *gru,
101 		void __user *ubuf, void __user *ubufend)
102 {
103 	struct gru_tlb_global_handle *tgh;
104 	int i;
105 
106 	if (GRU_NUM_TGH * GRU_CACHE_LINE_BYTES > ubufend - ubuf)
107 		return -EFBIG;
108 
109 	for (i = 0; i < GRU_NUM_TGH; i++) {
110 		tgh = get_tgh(gru->gs_gru_base_vaddr, i);
111 		if (gru_user_copy_handle(&ubuf, tgh))
112 			goto fail;
113 	}
114 	return GRU_NUM_TGH * GRU_CACHE_LINE_BYTES;
115 
116 fail:
117 	return -EFAULT;
118 }
119 
120 static int gru_dump_context(struct gru_state *gru, int ctxnum,
121 		void __user *ubuf, void __user *ubufend, char data_opt,
122 		char lock_cch, char flush_cbrs)
123 {
124 	struct gru_dump_context_header hdr;
125 	struct gru_dump_context_header __user *uhdr = ubuf;
126 	struct gru_context_configuration_handle *cch, *ubufcch;
127 	struct gru_thread_state *gts;
128 	int try, cch_locked, cbrcnt = 0, dsrcnt = 0, bytes = 0, ret = 0;
129 	void *grubase;
130 
131 	memset(&hdr, 0, sizeof(hdr));
132 	grubase = gru->gs_gru_base_vaddr;
133 	cch = get_cch(grubase, ctxnum);
134 	for (try = 0; try < CCH_LOCK_ATTEMPTS; try++) {
135 		cch_locked =  trylock_cch_handle(cch);
136 		if (cch_locked)
137 			break;
138 		msleep(1);
139 	}
140 
141 	ubuf += sizeof(hdr);
142 	ubufcch = ubuf;
143 	if (gru_user_copy_handle(&ubuf, cch)) {
144 		if (cch_locked)
145 			unlock_cch_handle(cch);
146 		return -EFAULT;
147 	}
148 	if (cch_locked)
149 		ubufcch->delresp = 0;
150 	bytes = sizeof(hdr) + GRU_CACHE_LINE_BYTES;
151 
152 	if (cch_locked || !lock_cch) {
153 		gts = gru->gs_gts[ctxnum];
154 		if (gts && gts->ts_vma) {
155 			hdr.pid = gts->ts_tgid_owner;
156 			hdr.vaddr = gts->ts_vma->vm_start;
157 		}
158 		if (cch->state != CCHSTATE_INACTIVE) {
159 			cbrcnt = hweight64(cch->cbr_allocation_map) *
160 						GRU_CBR_AU_SIZE;
161 			dsrcnt = data_opt ? hweight32(cch->dsr_allocation_map) *
162 						GRU_DSR_AU_CL : 0;
163 		}
164 		bytes += (3 * cbrcnt + dsrcnt) * GRU_CACHE_LINE_BYTES;
165 		if (bytes > ubufend - ubuf)
166 			ret = -EFBIG;
167 		else
168 			ret = gru_dump_context_data(grubase, cch, ubuf, ctxnum,
169 							dsrcnt, flush_cbrs);
170 	}
171 	if (cch_locked)
172 		unlock_cch_handle(cch);
173 	if (ret)
174 		return ret;
175 
176 	hdr.magic = GRU_DUMP_MAGIC;
177 	hdr.gid = gru->gs_gid;
178 	hdr.ctxnum = ctxnum;
179 	hdr.cbrcnt = cbrcnt;
180 	hdr.dsrcnt = dsrcnt;
181 	hdr.cch_locked = cch_locked;
182 	if (copy_to_user(uhdr, &hdr, sizeof(hdr)))
183 		return -EFAULT;
184 
185 	return bytes;
186 }
187 
188 int gru_dump_chiplet_request(unsigned long arg)
189 {
190 	struct gru_state *gru;
191 	struct gru_dump_chiplet_state_req req;
192 	void __user *ubuf;
193 	void __user *ubufend;
194 	int ctxnum, ret, cnt = 0;
195 
196 	if (copy_from_user(&req, (void __user *)arg, sizeof(req)))
197 		return -EFAULT;
198 
199 	/* Currently, only dump by gid is implemented */
200 	if (req.gid >= gru_max_gids)
201 		return -EINVAL;
202 	req.gid = array_index_nospec(req.gid, gru_max_gids);
203 
204 	gru = GID_TO_GRU(req.gid);
205 	ubuf = req.buf;
206 	ubufend = req.buf + req.buflen;
207 
208 	ret = gru_dump_tfm(gru, ubuf, ubufend);
209 	if (ret < 0)
210 		goto fail;
211 	ubuf += ret;
212 
213 	ret = gru_dump_tgh(gru, ubuf, ubufend);
214 	if (ret < 0)
215 		goto fail;
216 	ubuf += ret;
217 
218 	for (ctxnum = 0; ctxnum < GRU_NUM_CCH; ctxnum++) {
219 		if (req.ctxnum == ctxnum || req.ctxnum < 0) {
220 			ret = gru_dump_context(gru, ctxnum, ubuf, ubufend,
221 						req.data_opt, req.lock_cch,
222 						req.flush_cbrs);
223 			if (ret < 0)
224 				goto fail;
225 			ubuf += ret;
226 			cnt++;
227 		}
228 	}
229 
230 	if (copy_to_user((void __user *)arg, &req, sizeof(req)))
231 		return -EFAULT;
232 	return cnt;
233 
234 fail:
235 	return ret;
236 }
237