1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * SN Platform GRU Driver
4 *
5 *            Dump GRU State
6 *
7 *  Copyright (c) 2008 Silicon Graphics, Inc.  All Rights Reserved.
8 */
9
10#include <linux/kernel.h>
11#include <linux/mm.h>
12#include <linux/spinlock.h>
13#include <linux/uaccess.h>
14#include <linux/delay.h>
15#include <linux/bitops.h>
16#include <asm/uv/uv_hub.h>
17
18#include <linux/nospec.h>
19
20#include "gru.h"
21#include "grutables.h"
22#include "gruhandles.h"
23#include "grulib.h"
24
25#define CCH_LOCK_ATTEMPTS	10
26
27static int gru_user_copy_handle(void __user **dp, void *s)
28{
29	if (copy_to_user(*dp, s, GRU_HANDLE_BYTES))
30		return -1;
31	*dp += GRU_HANDLE_BYTES;
32	return 0;
33}
34
35static int gru_dump_context_data(void *grubase,
36			struct gru_context_configuration_handle *cch,
37			void __user *ubuf, int ctxnum, int dsrcnt,
38			int flush_cbrs)
39{
40	void *cb, *cbe, *tfh, *gseg;
41	int i, scr;
42
43	gseg = grubase + ctxnum * GRU_GSEG_STRIDE;
44	cb = gseg + GRU_CB_BASE;
45	cbe = grubase + GRU_CBE_BASE;
46	tfh = grubase + GRU_TFH_BASE;
47
48	for_each_cbr_in_allocation_map(i, &cch->cbr_allocation_map, scr) {
49		if (flush_cbrs)
50			gru_flush_cache(cb);
51		if (gru_user_copy_handle(&ubuf, cb))
52			goto fail;
53		if (gru_user_copy_handle(&ubuf, tfh + i * GRU_HANDLE_STRIDE))
54			goto fail;
55		if (gru_user_copy_handle(&ubuf, cbe + i * GRU_HANDLE_STRIDE))
56			goto fail;
57		cb += GRU_HANDLE_STRIDE;
58	}
59	if (dsrcnt)
60		memcpy(ubuf, gseg + GRU_DS_BASE, dsrcnt * GRU_HANDLE_STRIDE);
61	return 0;
62
63fail:
64	return -EFAULT;
65}
66
67static int gru_dump_tfm(struct gru_state *gru,
68		void __user *ubuf, void __user *ubufend)
69{
70	struct gru_tlb_fault_map *tfm;
71	int i;
72
73	if (GRU_NUM_TFM * GRU_CACHE_LINE_BYTES > ubufend - ubuf)
74		return -EFBIG;
75
76	for (i = 0; i < GRU_NUM_TFM; i++) {
77		tfm = get_tfm(gru->gs_gru_base_vaddr, i);
78		if (gru_user_copy_handle(&ubuf, tfm))
79			goto fail;
80	}
81	return GRU_NUM_TFM * GRU_CACHE_LINE_BYTES;
82
83fail:
84	return -EFAULT;
85}
86
87static int gru_dump_tgh(struct gru_state *gru,
88		void __user *ubuf, void __user *ubufend)
89{
90	struct gru_tlb_global_handle *tgh;
91	int i;
92
93	if (GRU_NUM_TGH * GRU_CACHE_LINE_BYTES > ubufend - ubuf)
94		return -EFBIG;
95
96	for (i = 0; i < GRU_NUM_TGH; i++) {
97		tgh = get_tgh(gru->gs_gru_base_vaddr, i);
98		if (gru_user_copy_handle(&ubuf, tgh))
99			goto fail;
100	}
101	return GRU_NUM_TGH * GRU_CACHE_LINE_BYTES;
102
103fail:
104	return -EFAULT;
105}
106
107static int gru_dump_context(struct gru_state *gru, int ctxnum,
108		void __user *ubuf, void __user *ubufend, char data_opt,
109		char lock_cch, char flush_cbrs)
110{
111	struct gru_dump_context_header hdr;
112	struct gru_dump_context_header __user *uhdr = ubuf;
113	struct gru_context_configuration_handle *cch, *ubufcch;
114	struct gru_thread_state *gts;
115	int try, cch_locked, cbrcnt = 0, dsrcnt = 0, bytes = 0, ret = 0;
116	void *grubase;
117
118	memset(&hdr, 0, sizeof(hdr));
119	grubase = gru->gs_gru_base_vaddr;
120	cch = get_cch(grubase, ctxnum);
121	for (try = 0; try < CCH_LOCK_ATTEMPTS; try++) {
122		cch_locked =  trylock_cch_handle(cch);
123		if (cch_locked)
124			break;
125		msleep(1);
126	}
127
128	ubuf += sizeof(hdr);
129	ubufcch = ubuf;
130	if (gru_user_copy_handle(&ubuf, cch)) {
131		if (cch_locked)
132			unlock_cch_handle(cch);
133		return -EFAULT;
134	}
135	if (cch_locked)
136		ubufcch->delresp = 0;
137	bytes = sizeof(hdr) + GRU_CACHE_LINE_BYTES;
138
139	if (cch_locked || !lock_cch) {
140		gts = gru->gs_gts[ctxnum];
141		if (gts && gts->ts_vma) {
142			hdr.pid = gts->ts_tgid_owner;
143			hdr.vaddr = gts->ts_vma->vm_start;
144		}
145		if (cch->state != CCHSTATE_INACTIVE) {
146			cbrcnt = hweight64(cch->cbr_allocation_map) *
147						GRU_CBR_AU_SIZE;
148			dsrcnt = data_opt ? hweight32(cch->dsr_allocation_map) *
149						GRU_DSR_AU_CL : 0;
150		}
151		bytes += (3 * cbrcnt + dsrcnt) * GRU_CACHE_LINE_BYTES;
152		if (bytes > ubufend - ubuf)
153			ret = -EFBIG;
154		else
155			ret = gru_dump_context_data(grubase, cch, ubuf, ctxnum,
156							dsrcnt, flush_cbrs);
157	}
158	if (cch_locked)
159		unlock_cch_handle(cch);
160	if (ret)
161		return ret;
162
163	hdr.magic = GRU_DUMP_MAGIC;
164	hdr.gid = gru->gs_gid;
165	hdr.ctxnum = ctxnum;
166	hdr.cbrcnt = cbrcnt;
167	hdr.dsrcnt = dsrcnt;
168	hdr.cch_locked = cch_locked;
169	if (copy_to_user(uhdr, &hdr, sizeof(hdr)))
170		return -EFAULT;
171
172	return bytes;
173}
174
175int gru_dump_chiplet_request(unsigned long arg)
176{
177	struct gru_state *gru;
178	struct gru_dump_chiplet_state_req req;
179	void __user *ubuf;
180	void __user *ubufend;
181	int ctxnum, ret, cnt = 0;
182
183	if (copy_from_user(&req, (void __user *)arg, sizeof(req)))
184		return -EFAULT;
185
186	/* Currently, only dump by gid is implemented */
187	if (req.gid >= gru_max_gids)
188		return -EINVAL;
189	req.gid = array_index_nospec(req.gid, gru_max_gids);
190
191	gru = GID_TO_GRU(req.gid);
192	ubuf = req.buf;
193	ubufend = req.buf + req.buflen;
194
195	ret = gru_dump_tfm(gru, ubuf, ubufend);
196	if (ret < 0)
197		goto fail;
198	ubuf += ret;
199
200	ret = gru_dump_tgh(gru, ubuf, ubufend);
201	if (ret < 0)
202		goto fail;
203	ubuf += ret;
204
205	for (ctxnum = 0; ctxnum < GRU_NUM_CCH; ctxnum++) {
206		if (req.ctxnum == ctxnum || req.ctxnum < 0) {
207			ret = gru_dump_context(gru, ctxnum, ubuf, ubufend,
208						req.data_opt, req.lock_cch,
209						req.flush_cbrs);
210			if (ret < 0)
211				goto fail;
212			ubuf += ret;
213			cnt++;
214		}
215	}
216
217	if (copy_to_user((void __user *)arg, &req, sizeof(req)))
218		return -EFAULT;
219	return cnt;
220
221fail:
222	return ret;
223}
224