xref: /openbmc/linux/drivers/s390/char/sclp_ftp.c (revision f4356947)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  *    SCLP Event Type (ET) 7 - Diagnostic Test FTP Services, useable on LPAR
4  *
5  *    Copyright IBM Corp. 2013
6  *    Author(s): Ralf Hoppe (rhoppe@de.ibm.com)
7  *
8  */
9 
10 #define KMSG_COMPONENT "hmcdrv"
11 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
12 
13 #include <linux/kernel.h>
14 #include <linux/mm.h>
15 #include <linux/slab.h>
16 #include <linux/io.h>
17 #include <linux/wait.h>
18 #include <linux/string.h>
19 #include <linux/jiffies.h>
20 #include <asm/sysinfo.h>
21 #include <asm/ebcdic.h>
22 
23 #include "sclp.h"
24 #include "sclp_diag.h"
25 #include "sclp_ftp.h"
26 
27 static DECLARE_COMPLETION(sclp_ftp_rx_complete);
28 static u8 sclp_ftp_ldflg;
29 static u64 sclp_ftp_fsize;
30 static u64 sclp_ftp_length;
31 
32 /**
33  * sclp_ftp_txcb() - Diagnostic Test FTP services SCLP command callback
34  * @req: sclp request
35  * @data: pointer to struct completion
36  */
37 static void sclp_ftp_txcb(struct sclp_req *req, void *data)
38 {
39 	struct completion *completion = data;
40 
41 #ifdef DEBUG
42 	pr_debug("SCLP (ET7) TX-IRQ, SCCB @ 0x%p: %*phN\n",
43 		 req->sccb, 24, req->sccb);
44 #endif
45 	complete(completion);
46 }
47 
48 /**
49  * sclp_ftp_rxcb() - Diagnostic Test FTP services receiver event callback
50  * @evbuf: pointer to Diagnostic Test (ET7) event buffer
51  */
52 static void sclp_ftp_rxcb(struct evbuf_header *evbuf)
53 {
54 	struct sclp_diag_evbuf *diag = (struct sclp_diag_evbuf *) evbuf;
55 
56 	/*
57 	 * Check for Diagnostic Test FTP Service
58 	 */
59 	if (evbuf->type != EVTYP_DIAG_TEST ||
60 	    diag->route != SCLP_DIAG_FTP_ROUTE ||
61 	    diag->mdd.ftp.pcx != SCLP_DIAG_FTP_XPCX ||
62 	    evbuf->length < SCLP_DIAG_FTP_EVBUF_LEN)
63 		return;
64 
65 #ifdef DEBUG
66 	pr_debug("SCLP (ET7) RX-IRQ, Event @ 0x%p: %*phN\n",
67 		 evbuf, 24, evbuf);
68 #endif
69 
70 	/*
71 	 * Because the event buffer is located in a page which is owned
72 	 * by the SCLP core, all data of interest must be copied. The
73 	 * error indication is in 'sclp_ftp_ldflg'
74 	 */
75 	sclp_ftp_ldflg = diag->mdd.ftp.ldflg;
76 	sclp_ftp_fsize = diag->mdd.ftp.fsize;
77 	sclp_ftp_length = diag->mdd.ftp.length;
78 
79 	complete(&sclp_ftp_rx_complete);
80 }
81 
82 /**
83  * sclp_ftp_et7() - start a Diagnostic Test FTP Service SCLP request
84  * @ftp: pointer to FTP descriptor
85  *
86  * Return: 0 on success, else a (negative) error code
87  */
88 static int sclp_ftp_et7(const struct hmcdrv_ftp_cmdspec *ftp)
89 {
90 	struct completion completion;
91 	struct sclp_diag_sccb *sccb;
92 	struct sclp_req *req;
93 	ssize_t len;
94 	int rc;
95 
96 	req = kzalloc(sizeof(*req), GFP_KERNEL);
97 	sccb = (void *) get_zeroed_page(GFP_KERNEL | GFP_DMA);
98 	if (!req || !sccb) {
99 		rc = -ENOMEM;
100 		goto out_free;
101 	}
102 
103 	sccb->hdr.length = SCLP_DIAG_FTP_EVBUF_LEN +
104 		sizeof(struct sccb_header);
105 	sccb->evbuf.hdr.type = EVTYP_DIAG_TEST;
106 	sccb->evbuf.hdr.length = SCLP_DIAG_FTP_EVBUF_LEN;
107 	sccb->evbuf.hdr.flags = 0; /* clear processed-buffer */
108 	sccb->evbuf.route = SCLP_DIAG_FTP_ROUTE;
109 	sccb->evbuf.mdd.ftp.pcx = SCLP_DIAG_FTP_XPCX;
110 	sccb->evbuf.mdd.ftp.srcflg = 0;
111 	sccb->evbuf.mdd.ftp.pgsize = 0;
112 	sccb->evbuf.mdd.ftp.asce = _ASCE_REAL_SPACE;
113 	sccb->evbuf.mdd.ftp.ldflg = SCLP_DIAG_FTP_LDFAIL;
114 	sccb->evbuf.mdd.ftp.fsize = 0;
115 	sccb->evbuf.mdd.ftp.cmd = ftp->id;
116 	sccb->evbuf.mdd.ftp.offset = ftp->ofs;
117 	sccb->evbuf.mdd.ftp.length = ftp->len;
118 	sccb->evbuf.mdd.ftp.bufaddr = virt_to_phys(ftp->buf);
119 
120 	len = strscpy(sccb->evbuf.mdd.ftp.fident, ftp->fname,
121 		      HMCDRV_FTP_FIDENT_MAX);
122 	if (len < 0) {
123 		rc = -EINVAL;
124 		goto out_free;
125 	}
126 
127 	req->command = SCLP_CMDW_WRITE_EVENT_DATA;
128 	req->sccb = sccb;
129 	req->status = SCLP_REQ_FILLED;
130 	req->callback = sclp_ftp_txcb;
131 	req->callback_data = &completion;
132 
133 	init_completion(&completion);
134 
135 	rc = sclp_add_request(req);
136 	if (rc)
137 		goto out_free;
138 
139 	/* Wait for end of ftp sclp command. */
140 	wait_for_completion(&completion);
141 
142 #ifdef DEBUG
143 	pr_debug("status of SCLP (ET7) request is 0x%04x (0x%02x)\n",
144 		 sccb->hdr.response_code, sccb->evbuf.hdr.flags);
145 #endif
146 
147 	/*
148 	 * Check if sclp accepted the request. The data transfer runs
149 	 * asynchronously and the completion is indicated with an
150 	 * sclp ET7 event.
151 	 */
152 	if (req->status != SCLP_REQ_DONE ||
153 	    (sccb->evbuf.hdr.flags & 0x80) == 0 || /* processed-buffer */
154 	    (sccb->hdr.response_code & 0xffU) != 0x20U) {
155 		rc = -EIO;
156 	}
157 
158 out_free:
159 	free_page((unsigned long) sccb);
160 	kfree(req);
161 	return rc;
162 }
163 
164 /**
165  * sclp_ftp_cmd() - executes a HMC related SCLP Diagnose (ET7) FTP command
166  * @ftp: pointer to FTP command specification
167  * @fsize: return of file size (or NULL if undesirable)
168  *
169  * Attention: Notice that this function is not reentrant - so the caller
170  * must ensure locking.
171  *
172  * Return: number of bytes read/written or a (negative) error code
173  */
174 ssize_t sclp_ftp_cmd(const struct hmcdrv_ftp_cmdspec *ftp, size_t *fsize)
175 {
176 	ssize_t len;
177 #ifdef DEBUG
178 	unsigned long start_jiffies;
179 
180 	pr_debug("starting SCLP (ET7), cmd %d for '%s' at %lld with %zd bytes\n",
181 		 ftp->id, ftp->fname, (long long) ftp->ofs, ftp->len);
182 	start_jiffies = jiffies;
183 #endif
184 
185 	init_completion(&sclp_ftp_rx_complete);
186 
187 	/* Start ftp sclp command. */
188 	len = sclp_ftp_et7(ftp);
189 	if (len)
190 		goto out_unlock;
191 
192 	/*
193 	 * There is no way to cancel the sclp ET7 request, the code
194 	 * needs to wait unconditionally until the transfer is complete.
195 	 */
196 	wait_for_completion(&sclp_ftp_rx_complete);
197 
198 #ifdef DEBUG
199 	pr_debug("completed SCLP (ET7) request after %lu ms (all)\n",
200 		 (jiffies - start_jiffies) * 1000 / HZ);
201 	pr_debug("return code of SCLP (ET7) FTP Service is 0x%02x, with %lld/%lld bytes\n",
202 		 sclp_ftp_ldflg, sclp_ftp_length, sclp_ftp_fsize);
203 #endif
204 
205 	switch (sclp_ftp_ldflg) {
206 	case SCLP_DIAG_FTP_OK:
207 		len = sclp_ftp_length;
208 		if (fsize)
209 			*fsize = sclp_ftp_fsize;
210 		break;
211 	case SCLP_DIAG_FTP_LDNPERM:
212 		len = -EPERM;
213 		break;
214 	case SCLP_DIAG_FTP_LDRUNS:
215 		len = -EBUSY;
216 		break;
217 	case SCLP_DIAG_FTP_LDFAIL:
218 		len = -ENOENT;
219 		break;
220 	default:
221 		len = -EIO;
222 		break;
223 	}
224 
225 out_unlock:
226 	return len;
227 }
228 
229 /*
230  * ET7 event listener
231  */
232 static struct sclp_register sclp_ftp_event = {
233 	.send_mask = EVTYP_DIAG_TEST_MASK,    /* want tx events */
234 	.receive_mask = EVTYP_DIAG_TEST_MASK, /* want rx events */
235 	.receiver_fn = sclp_ftp_rxcb,	      /* async callback (rx) */
236 	.state_change_fn = NULL,
237 };
238 
239 /**
240  * sclp_ftp_startup() - startup of FTP services, when running on LPAR
241  */
242 int sclp_ftp_startup(void)
243 {
244 #ifdef DEBUG
245 	unsigned long info;
246 #endif
247 	int rc;
248 
249 	rc = sclp_register(&sclp_ftp_event);
250 	if (rc)
251 		return rc;
252 
253 #ifdef DEBUG
254 	info = get_zeroed_page(GFP_KERNEL);
255 
256 	if (info != 0) {
257 		struct sysinfo_2_2_2 *info222 = (struct sysinfo_2_2_2 *)info;
258 
259 		if (!stsi(info222, 2, 2, 2)) { /* get SYSIB 2.2.2 */
260 			info222->name[sizeof(info222->name) - 1] = '\0';
261 			EBCASC_500(info222->name, sizeof(info222->name) - 1);
262 			pr_debug("SCLP (ET7) FTP Service working on LPAR %u (%s)\n",
263 				 info222->lpar_number, info222->name);
264 		}
265 
266 		free_page(info);
267 	}
268 #endif	/* DEBUG */
269 	return 0;
270 }
271 
272 /**
273  * sclp_ftp_shutdown() - shutdown of FTP services, when running on LPAR
274  */
275 void sclp_ftp_shutdown(void)
276 {
277 	sclp_unregister(&sclp_ftp_event);
278 }
279