summaryrefslogtreecommitdiff
path: root/drivers/scsi/cxlflash/lunmgt.c
blob: e0e15b44a2e6aac9751e6e3cb330914a15614e58 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * CXL Flash Device Driver
 *
 * Written by: Manoj N. Kumar <manoj@linux.vnet.ibm.com>, IBM Corporation
 *             Matthew R. Ochs <mrochs@linux.vnet.ibm.com>, IBM Corporation
 *
 * Copyright (C) 2015 IBM Corporation
 */

#include <asm/unaligned.h>

#include <linux/interrupt.h>
#include <linux/pci.h>

#include <scsi/scsi_host.h>
#include <uapi/scsi/cxlflash_ioctl.h>

#include "sislite.h"
#include "common.h"
#include "vlun.h"
#include "superpipe.h"

/**
 * create_local() - allocate and initialize a local LUN information structure
 * @sdev:	SCSI device associated with LUN.
 * @wwid:	World Wide Node Name for LUN.
 *
 * Return: Allocated local llun_info structure on success, NULL on failure
 */
static struct llun_info *create_local(struct scsi_device *sdev, u8 *wwid)
{
	struct cxlflash_cfg *cfg = shost_priv(sdev->host);
	struct device *dev = &cfg->dev->dev;
	struct llun_info *lli = NULL;

	lli = kzalloc(sizeof(*lli), GFP_KERNEL);
	if (unlikely(!lli)) {
		dev_err(dev, "%s: could not allocate lli\n", __func__);
		goto out;
	}

	lli->sdev = sdev;
	lli->host_no = sdev->host->host_no;
	lli->in_table = false;

	memcpy(lli->wwid, wwid, DK_CXLFLASH_MANAGE_LUN_WWID_LEN);
out:
	return lli;
}

/**
 * create_global() - allocate and initialize a global LUN information structure
 * @sdev:	SCSI device associated with LUN.
 * @wwid:	World Wide Node Name for LUN.
 *
 * Return: Allocated global glun_info structure on success, NULL on failure
 */
static struct glun_info *create_global(struct scsi_device *sdev, u8 *wwid)
{
	struct cxlflash_cfg *cfg = shost_priv(sdev->host);
	struct device *dev = &cfg->dev->dev;
	struct glun_info *gli = NULL;

	gli = kzalloc(sizeof(*gli), GFP_KERNEL);
	if (unlikely(!gli)) {
		dev_err(dev, "%s: could not allocate gli\n", __func__);
		goto out;
	}

	mutex_init(&gli->mutex);
	memcpy(gli->wwid, wwid, DK_CXLFLASH_MANAGE_LUN_WWID_LEN);
out:
	return gli;
}

/**
 * lookup_local() - find a local LUN information structure by WWID
 * @cfg:	Internal structure associated with the host.
 * @wwid:	WWID associated with LUN.
 *
 * Return: Found local lun_info structure on success, NULL on failure
 */
static struct llun_info *lookup_local(struct cxlflash_cfg *cfg, u8 *wwid)
{
	struct llun_info *lli, *temp;

	list_for_each_entry_safe(lli, temp, &cfg->lluns, list)
		if (!memcmp(lli->wwid, wwid, DK_CXLFLASH_MANAGE_LUN_WWID_LEN))
			return lli;

	return NULL;
}

/**
 * lookup_global() - find a global LUN information structure by WWID
 * @wwid:	WWID associated with LUN.
 *
 * Return: Found global lun_info structure on success, NULL on failure
 */
static struct glun_info *lookup_global(u8 *wwid)
{
	struct glun_info *gli, *temp;

	list_for_each_entry_safe(gli, temp, &global.gluns, list)
		if (!memcmp(gli->wwid, wwid, DK_CXLFLASH_MANAGE_LUN_WWID_LEN))
			return gli;

	return NULL;
}

/**
 * find_and_create_lun() - find or create a local LUN information structure
 * @sdev:	SCSI device associated with LUN.
 * @wwid:	WWID associated with LUN.
 *
 * The LUN is kept both in a local list (per adapter) and in a global list
 * (across all adapters). Certain attributes of the LUN are local to the
 * adapter (such as index, port selection mask, etc.).
 *
 * The block allocation map is shared across all adapters (i.e. associated
 * wih the global list). Since different attributes are associated with
 * the per adapter and global entries, allocate two separate structures for each
 * LUN (one local, one global).
 *
 * Keep a pointer back from the local to the global entry.
 *
 * This routine assumes the caller holds the global mutex.
 *
 * Return: Found/Allocated local lun_info structure on success, NULL on failure
 */
static struct llun_info *find_and_create_lun(struct scsi_device *sdev, u8 *wwid)
{
	struct cxlflash_cfg *cfg = shost_priv(sdev->host);
	struct device *dev = &cfg->dev->dev;
	struct llun_info *lli = NULL;
	struct glun_info *gli = NULL;

	if (unlikely(!wwid))
		goto out;

	lli = lookup_local(cfg, wwid);
	if (lli)
		goto out;

	lli = create_local(sdev, wwid);
	if (unlikely(!lli))
		goto out;

	gli = lookup_global(wwid);
	if (gli) {
		lli->parent = gli;
		list_add(&lli->list, &cfg->lluns);
		goto out;
	}

	gli = create_global(sdev, wwid);
	if (unlikely(!gli)) {
		kfree(lli);
		lli = NULL;
		goto out;
	}

	lli->parent = gli;
	list_add(&lli->list, &cfg->lluns);

	list_add(&gli->list, &global.gluns);

out:
	dev_dbg(dev, "%s: returning lli=%p, gli=%p\n", __func__, lli, gli);
	return lli;
}

/**
 * cxlflash_term_local_luns() - Delete all entries from local LUN list, free.
 * @cfg:	Internal structure associated with the host.
 */
void cxlflash_term_local_luns(struct cxlflash_cfg *cfg)
{
	struct llun_info *lli, *temp;

	mutex_lock(&global.mutex);
	list_for_each_entry_safe(lli, temp, &cfg->lluns, list) {
		list_del(&lli->list);
		kfree(lli);
	}
	mutex_unlock(&global.mutex);
}

/**
 * cxlflash_list_init() - initializes the global LUN list
 */
void cxlflash_list_init(void)
{
	INIT_LIST_HEAD(&global.gluns);
	mutex_init(&global.mutex);
	global.err_page = NULL;
}

/**
 * cxlflash_term_global_luns() - frees resources associated with global LUN list
 */
void cxlflash_term_global_luns(void)
{
	struct glun_info *gli, *temp;

	mutex_lock(&global.mutex);
	list_for_each_entry_safe(gli, temp, &global.gluns, list) {
		list_del(&gli->list);
		cxlflash_ba_terminate(&gli->blka.ba_lun);
		kfree(gli);
	}
	mutex_unlock(&global.mutex);
}

/**
 * cxlflash_manage_lun() - handles LUN management activities
 * @sdev:	SCSI device associated with LUN.
 * @manage:	Manage ioctl data structure.
 *
 * This routine is used to notify the driver about a LUN's WWID and associate
 * SCSI devices (sdev) with a global LUN instance. Additionally it serves to
 * change a LUN's operating mode: legacy or superpipe.
 *
 * Return: 0 on success, -errno on failure
 */
int cxlflash_manage_lun(struct scsi_device *sdev,
			struct dk_cxlflash_manage_lun *manage)
{
	struct cxlflash_cfg *cfg = shost_priv(sdev->host);
	struct device *dev = &cfg->dev->dev;
	struct llun_info *lli = NULL;
	int rc = 0;
	u64 flags = manage->hdr.flags;
	u32 chan = sdev->channel;

	mutex_lock(&global.mutex);
	lli = find_and_create_lun(sdev, manage->wwid);
	dev_dbg(dev, "%s: WWID=%016llx%016llx, flags=%016llx lli=%p\n",
		__func__, get_unaligned_be64(&manage->wwid[0]),
		get_unaligned_be64(&manage->wwid[8]), manage->hdr.flags, lli);
	if (unlikely(!lli)) {
		rc = -ENOMEM;
		goto out;
	}

	if (flags & DK_CXLFLASH_MANAGE_LUN_ENABLE_SUPERPIPE) {
		/*
		 * Update port selection mask based upon channel, store off LUN
		 * in unpacked, AFU-friendly format, and hang LUN reference in
		 * the sdev.
		 */
		lli->port_sel |= CHAN2PORTMASK(chan);
		lli->lun_id[chan] = lun_to_lunid(sdev->lun);
		sdev->hostdata = lli;
	} else if (flags & DK_CXLFLASH_MANAGE_LUN_DISABLE_SUPERPIPE) {
		if (lli->parent->mode != MODE_NONE)
			rc = -EBUSY;
		else {
			/*
			 * Clean up local LUN for this port and reset table
			 * tracking when no more references exist.
			 */
			sdev->hostdata = NULL;
			lli->port_sel &= ~CHAN2PORTMASK(chan);
			if (lli->port_sel == 0U)
				lli->in_table = false;
		}
	}

	dev_dbg(dev, "%s: port_sel=%08x chan=%u lun_id=%016llx\n",
		__func__, lli->port_sel, chan, lli->lun_id[chan]);

out:
	mutex_unlock(&global.mutex);
	dev_dbg(dev, "%s: returning rc=%d\n", __func__, rc);
	return rc;
}