xref: /linux/drivers/virtio/virtio_pci_admin_legacy_io.c (revision 4b660dbd9ee2059850fd30e0df420ca7a38a1856)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (c) 2023, NVIDIA CORPORATION & AFFILIATES. All rights reserved
4  */
5 
6 #include <linux/virtio_pci_admin.h>
7 #include "virtio_pci_common.h"
8 
9 /*
10  * virtio_pci_admin_has_legacy_io - Checks whether the legacy IO
11  * commands are supported
12  * @dev: VF pci_dev
13  *
14  * Returns true on success.
15  */
16 bool virtio_pci_admin_has_legacy_io(struct pci_dev *pdev)
17 {
18 	struct virtio_device *virtio_dev = virtio_pci_vf_get_pf_dev(pdev);
19 	struct virtio_pci_device *vp_dev;
20 
21 	if (!virtio_dev)
22 		return false;
23 
24 	if (!virtio_has_feature(virtio_dev, VIRTIO_F_ADMIN_VQ))
25 		return false;
26 
27 	vp_dev = to_vp_device(virtio_dev);
28 
29 	if ((vp_dev->admin_vq.supported_cmds & VIRTIO_LEGACY_ADMIN_CMD_BITMAP) ==
30 		VIRTIO_LEGACY_ADMIN_CMD_BITMAP)
31 		return true;
32 	return false;
33 }
34 EXPORT_SYMBOL_GPL(virtio_pci_admin_has_legacy_io);
35 
36 static int virtio_pci_admin_legacy_io_write(struct pci_dev *pdev, u16 opcode,
37 					    u8 offset, u8 size, u8 *buf)
38 {
39 	struct virtio_device *virtio_dev = virtio_pci_vf_get_pf_dev(pdev);
40 	struct virtio_admin_cmd_legacy_wr_data *data;
41 	struct virtio_admin_cmd cmd = {};
42 	struct scatterlist data_sg;
43 	int vf_id;
44 	int ret;
45 
46 	if (!virtio_dev)
47 		return -ENODEV;
48 
49 	vf_id = pci_iov_vf_id(pdev);
50 	if (vf_id < 0)
51 		return vf_id;
52 
53 	data = kzalloc(sizeof(*data) + size, GFP_KERNEL);
54 	if (!data)
55 		return -ENOMEM;
56 
57 	data->offset = offset;
58 	memcpy(data->registers, buf, size);
59 	sg_init_one(&data_sg, data, sizeof(*data) + size);
60 	cmd.opcode = cpu_to_le16(opcode);
61 	cmd.group_type = cpu_to_le16(VIRTIO_ADMIN_GROUP_TYPE_SRIOV);
62 	cmd.group_member_id = cpu_to_le64(vf_id + 1);
63 	cmd.data_sg = &data_sg;
64 	ret = vp_modern_admin_cmd_exec(virtio_dev, &cmd);
65 
66 	kfree(data);
67 	return ret;
68 }
69 
70 /*
71  * virtio_pci_admin_legacy_io_write_common - Write legacy common configuration
72  * of a member device
73  * @dev: VF pci_dev
74  * @offset: starting byte offset within the common configuration area to write to
75  * @size: size of the data to write
76  * @buf: buffer which holds the data
77  *
78  * Note: caller must serialize access for the given device.
79  * Returns 0 on success, or negative on failure.
80  */
81 int virtio_pci_admin_legacy_common_io_write(struct pci_dev *pdev, u8 offset,
82 					    u8 size, u8 *buf)
83 {
84 	return virtio_pci_admin_legacy_io_write(pdev,
85 					VIRTIO_ADMIN_CMD_LEGACY_COMMON_CFG_WRITE,
86 					offset, size, buf);
87 }
88 EXPORT_SYMBOL_GPL(virtio_pci_admin_legacy_common_io_write);
89 
90 /*
91  * virtio_pci_admin_legacy_io_write_device - Write legacy device configuration
92  * of a member device
93  * @dev: VF pci_dev
94  * @offset: starting byte offset within the device configuration area to write to
95  * @size: size of the data to write
96  * @buf: buffer which holds the data
97  *
98  * Note: caller must serialize access for the given device.
99  * Returns 0 on success, or negative on failure.
100  */
101 int virtio_pci_admin_legacy_device_io_write(struct pci_dev *pdev, u8 offset,
102 					    u8 size, u8 *buf)
103 {
104 	return virtio_pci_admin_legacy_io_write(pdev,
105 					VIRTIO_ADMIN_CMD_LEGACY_DEV_CFG_WRITE,
106 					offset, size, buf);
107 }
108 EXPORT_SYMBOL_GPL(virtio_pci_admin_legacy_device_io_write);
109 
110 static int virtio_pci_admin_legacy_io_read(struct pci_dev *pdev, u16 opcode,
111 					   u8 offset, u8 size, u8 *buf)
112 {
113 	struct virtio_device *virtio_dev = virtio_pci_vf_get_pf_dev(pdev);
114 	struct virtio_admin_cmd_legacy_rd_data *data;
115 	struct scatterlist data_sg, result_sg;
116 	struct virtio_admin_cmd cmd = {};
117 	int vf_id;
118 	int ret;
119 
120 	if (!virtio_dev)
121 		return -ENODEV;
122 
123 	vf_id = pci_iov_vf_id(pdev);
124 	if (vf_id < 0)
125 		return vf_id;
126 
127 	data = kzalloc(sizeof(*data), GFP_KERNEL);
128 	if (!data)
129 		return -ENOMEM;
130 
131 	data->offset = offset;
132 	sg_init_one(&data_sg, data, sizeof(*data));
133 	sg_init_one(&result_sg, buf, size);
134 	cmd.opcode = cpu_to_le16(opcode);
135 	cmd.group_type = cpu_to_le16(VIRTIO_ADMIN_GROUP_TYPE_SRIOV);
136 	cmd.group_member_id = cpu_to_le64(vf_id + 1);
137 	cmd.data_sg = &data_sg;
138 	cmd.result_sg = &result_sg;
139 	ret = vp_modern_admin_cmd_exec(virtio_dev, &cmd);
140 
141 	kfree(data);
142 	return ret;
143 }
144 
145 /*
146  * virtio_pci_admin_legacy_device_io_read - Read legacy device configuration of
147  * a member device
148  * @dev: VF pci_dev
149  * @offset: starting byte offset within the device configuration area to read from
150  * @size: size of the data to be read
151  * @buf: buffer to hold the returned data
152  *
153  * Note: caller must serialize access for the given device.
154  * Returns 0 on success, or negative on failure.
155  */
156 int virtio_pci_admin_legacy_device_io_read(struct pci_dev *pdev, u8 offset,
157 					   u8 size, u8 *buf)
158 {
159 	return virtio_pci_admin_legacy_io_read(pdev,
160 					VIRTIO_ADMIN_CMD_LEGACY_DEV_CFG_READ,
161 					offset, size, buf);
162 }
163 EXPORT_SYMBOL_GPL(virtio_pci_admin_legacy_device_io_read);
164 
165 /*
166  * virtio_pci_admin_legacy_common_io_read - Read legacy common configuration of
167  * a member device
168  * @dev: VF pci_dev
169  * @offset: starting byte offset within the common configuration area to read from
170  * @size: size of the data to be read
171  * @buf: buffer to hold the returned data
172  *
173  * Note: caller must serialize access for the given device.
174  * Returns 0 on success, or negative on failure.
175  */
176 int virtio_pci_admin_legacy_common_io_read(struct pci_dev *pdev, u8 offset,
177 					   u8 size, u8 *buf)
178 {
179 	return virtio_pci_admin_legacy_io_read(pdev,
180 					VIRTIO_ADMIN_CMD_LEGACY_COMMON_CFG_READ,
181 					offset, size, buf);
182 }
183 EXPORT_SYMBOL_GPL(virtio_pci_admin_legacy_common_io_read);
184 
185 /*
186  * virtio_pci_admin_legacy_io_notify_info - Read the queue notification
187  * information for legacy interface
188  * @dev: VF pci_dev
189  * @req_bar_flags: requested bar flags
190  * @bar: on output the BAR number of the owner or member device
191  * @bar_offset: on output the offset within bar
192  *
193  * Returns 0 on success, or negative on failure.
194  */
195 int virtio_pci_admin_legacy_io_notify_info(struct pci_dev *pdev,
196 					   u8 req_bar_flags, u8 *bar,
197 					   u64 *bar_offset)
198 {
199 	struct virtio_device *virtio_dev = virtio_pci_vf_get_pf_dev(pdev);
200 	struct virtio_admin_cmd_notify_info_result *result;
201 	struct virtio_admin_cmd cmd = {};
202 	struct scatterlist result_sg;
203 	int vf_id;
204 	int ret;
205 
206 	if (!virtio_dev)
207 		return -ENODEV;
208 
209 	vf_id = pci_iov_vf_id(pdev);
210 	if (vf_id < 0)
211 		return vf_id;
212 
213 	result = kzalloc(sizeof(*result), GFP_KERNEL);
214 	if (!result)
215 		return -ENOMEM;
216 
217 	sg_init_one(&result_sg, result, sizeof(*result));
218 	cmd.opcode = cpu_to_le16(VIRTIO_ADMIN_CMD_LEGACY_NOTIFY_INFO);
219 	cmd.group_type = cpu_to_le16(VIRTIO_ADMIN_GROUP_TYPE_SRIOV);
220 	cmd.group_member_id = cpu_to_le64(vf_id + 1);
221 	cmd.result_sg = &result_sg;
222 	ret = vp_modern_admin_cmd_exec(virtio_dev, &cmd);
223 	if (!ret) {
224 		struct virtio_admin_cmd_notify_info_data *entry;
225 		int i;
226 
227 		ret = -ENOENT;
228 		for (i = 0; i < VIRTIO_ADMIN_CMD_MAX_NOTIFY_INFO; i++) {
229 			entry = &result->entries[i];
230 			if (entry->flags == VIRTIO_ADMIN_CMD_NOTIFY_INFO_FLAGS_END)
231 				break;
232 			if (entry->flags != req_bar_flags)
233 				continue;
234 			*bar = entry->bar;
235 			*bar_offset = le64_to_cpu(entry->offset);
236 			ret = 0;
237 			break;
238 		}
239 	}
240 
241 	kfree(result);
242 	return ret;
243 }
244 EXPORT_SYMBOL_GPL(virtio_pci_admin_legacy_io_notify_info);
245