1 // SPDX-License-Identifier: GPL-2.0-only
2 /* Copyright(c) 2024-2025 Intel Corporation. All rights reserved. */
11 #include <trace/events/tsm_mr.h>
14  * struct tm_context - contains everything necessary to implement sysfs
19  * @in_sync: %true if MR cache is up-to-date.
25  * Given tm->refresh() is potentially expensive, tm_digest_read() caches MR
26  * values and calls tm->refresh() only when necessary. Only live MRs (i.e., with
27  * %TSM_MR_F_LIVE set) can trigger tm->refresh(), while others are assumed to
28  * retain their values from the last tm->write(). @in_sync tracks if there have
29  * been tm->write() calls since the last tm->refresh(). That is, tm->refresh()
33  * tm_digest_write() sets @in_sync to %false and calls tm->write(), whose
35  * extension semantics (i.e., tm->write() extends the input buffer into the MR).
46 			      const struct bin_attribute *attr, char *buffer,  in tm_digest_read()  argument
53 	ctx = attr->private;  in tm_digest_read()
54 	rc = down_read_interruptible(&ctx->rwsem);  in tm_digest_read()
58 	mr = &ctx->tm->mrs[attr - ctx->mrs];  in tm_digest_read()
61 	 * @ctx->in_sync indicates if the MR cache is stale. It is a global  in tm_digest_read()
62 	 * instead of a per-MR flag for simplicity, as most (if not all) archs  in tm_digest_read()
65 	 * ctx->refresh() is necessary only for LIVE MRs, while others retain  in tm_digest_read()
66 	 * their values from their respective last ctx->write().  in tm_digest_read()
68 	if ((mr->mr_flags & TSM_MR_F_LIVE) && !ctx->in_sync) {  in tm_digest_read()
69 		up_read(&ctx->rwsem);  in tm_digest_read()
71 		rc = down_write_killable(&ctx->rwsem);  in tm_digest_read()
75 		if (!ctx->in_sync) {  in tm_digest_read()
76 			rc = ctx->tm->refresh(ctx->tm);  in tm_digest_read()
77 			ctx->in_sync = !rc;  in tm_digest_read()
81 		downgrade_write(&ctx->rwsem);  in tm_digest_read()
84 	memcpy(buffer, mr->mr_value + off, count);  in tm_digest_read()
87 	up_read(&ctx->rwsem);  in tm_digest_read()
92 			       const struct bin_attribute *attr, char *buffer,  in tm_digest_write()  argument
100 	if (off != 0 || count != attr->size)  in tm_digest_write()
101 		return -EINVAL;  in tm_digest_write()
103 	ctx = attr->private;  in tm_digest_write()
104 	mr = &ctx->tm->mrs[attr - ctx->mrs];  in tm_digest_write()
106 	rc = down_write_killable(&ctx->rwsem);  in tm_digest_write()
110 	rc = ctx->tm->write(ctx->tm, mr, buffer);  in tm_digest_write()
114 		ctx->in_sync = false;  in tm_digest_write()
115 		trace_tsm_mr_write(mr, buffer);  in tm_digest_write()
118 	up_write(&ctx->rwsem);  in tm_digest_write()
123  * tsm_mr_create_attribute_group() - creates an attribute group for measurement
128  * provided by @tm->mrs.
137  * * %-EINVAL - Invalid MR definitions.
138  * * %-ENOMEM - Out of memory.
145 	if (!tm || !tm->mrs)  in tsm_mr_create_attribute_group()
146 		return ERR_PTR(-EINVAL);  in tsm_mr_create_attribute_group()
150 	for (size_t i = 0; i < tm->nr_mrs; ++i) {  in tsm_mr_create_attribute_group()
151 		if ((tm->mrs[i].mr_flags & TSM_MR_F_LIVE) && !tm->refresh)  in tsm_mr_create_attribute_group()
152 			return ERR_PTR(-EINVAL);  in tsm_mr_create_attribute_group()
154 		if ((tm->mrs[i].mr_flags & TSM_MR_F_WRITABLE) && !tm->write)  in tsm_mr_create_attribute_group()
155 			return ERR_PTR(-EINVAL);  in tsm_mr_create_attribute_group()
157 		if (!tm->mrs[i].mr_name)  in tsm_mr_create_attribute_group()
158 			return ERR_PTR(-EINVAL);  in tsm_mr_create_attribute_group()
160 		if (tm->mrs[i].mr_flags & TSM_MR_F_NOHASH)  in tsm_mr_create_attribute_group()
163 		if (tm->mrs[i].mr_hash >= HASH_ALGO__LAST)  in tsm_mr_create_attribute_group()
164 			return ERR_PTR(-EINVAL);  in tsm_mr_create_attribute_group()
167 		nlen += strlen(tm->mrs[i].mr_name) + 1 +  in tsm_mr_create_attribute_group()
168 			strlen(hash_algo_name[tm->mrs[i].mr_hash]) + 1;  in tsm_mr_create_attribute_group()
173 	 * so that we don't have to free MR names one-by-one in  in tsm_mr_create_attribute_group()
177 		kzalloc(sizeof(*attrs) * (tm->nr_mrs + 1) + nlen, GFP_KERNEL);  in tsm_mr_create_attribute_group()
179 		kzalloc(struct_size(ctx, mrs, tm->nr_mrs), GFP_KERNEL);  in tsm_mr_create_attribute_group()
183 		return ERR_PTR(-ENOMEM);  in tsm_mr_create_attribute_group()
186 	name = (char *)&attrs[tm->nr_mrs + 1];  in tsm_mr_create_attribute_group()
189 	for (size_t i = 0; i < tm->nr_mrs; ++i) {  in tsm_mr_create_attribute_group()
190 		struct bin_attribute *bap = &ctx->mrs[i];  in tsm_mr_create_attribute_group()
194 		if (tm->mrs[i].mr_flags & TSM_MR_F_NOHASH)  in tsm_mr_create_attribute_group()
195 			bap->attr.name = tm->mrs[i].mr_name;  in tsm_mr_create_attribute_group()
197 			bap->attr.name = name;  in tsm_mr_create_attribute_group()
198 			name += snprintf(name, end - name, "%s:%s",  in tsm_mr_create_attribute_group()
199 					 tm->mrs[i].mr_name,  in tsm_mr_create_attribute_group()
200 					 hash_algo_name[tm->mrs[i].mr_hash]);  in tsm_mr_create_attribute_group()
203 			return ERR_PTR(-EINVAL);  in tsm_mr_create_attribute_group()
207 			if (!strcmp(bap->attr.name, attrs[j]->attr.name))  in tsm_mr_create_attribute_group()
208 				return ERR_PTR(-EINVAL);  in tsm_mr_create_attribute_group()
210 		if (tm->mrs[i].mr_flags & TSM_MR_F_READABLE) {  in tsm_mr_create_attribute_group()
211 			bap->attr.mode |= 0444;  in tsm_mr_create_attribute_group()
212 			bap->read = tm_digest_read;  in tsm_mr_create_attribute_group()
215 		if (tm->mrs[i].mr_flags & TSM_MR_F_WRITABLE) {  in tsm_mr_create_attribute_group()
216 			bap->attr.mode |= 0200;  in tsm_mr_create_attribute_group()
217 			bap->write = tm_digest_write;  in tsm_mr_create_attribute_group()
220 		bap->size = tm->mrs[i].mr_size;  in tsm_mr_create_attribute_group()
221 		bap->private = ctx;  in tsm_mr_create_attribute_group()
227 		return ERR_PTR(-EINVAL);  in tsm_mr_create_attribute_group()
229 	init_rwsem(&ctx->rwsem);  in tsm_mr_create_attribute_group()
230 	ctx->agrp.name = "measurements";  in tsm_mr_create_attribute_group()
231 	ctx->agrp.bin_attrs = no_free_ptr(attrs);  in tsm_mr_create_attribute_group()
232 	ctx->tm = tm;  in tsm_mr_create_attribute_group()
233 	return &no_free_ptr(ctx)->agrp;  in tsm_mr_create_attribute_group()
238  * tsm_mr_free_attribute_group() - frees the attribute group returned by
247 		kfree(attr_grp->bin_attrs);  in tsm_mr_free_attribute_group()