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8#define KMSG_COMPONENT "hmcdrv"
9#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
10
11#include <linux/kernel.h>
12#include <linux/slab.h>
13#include <linux/uaccess.h>
14#include <linux/export.h>
15
16#include <linux/ctype.h>
17#include <linux/crc16.h>
18
19#include "hmcdrv_ftp.h"
20#include "hmcdrv_cache.h"
21#include "sclp_ftp.h"
22#include "diag_ftp.h"
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29
30struct hmcdrv_ftp_ops {
31 int (*startup)(void);
32 void (*shutdown)(void);
33 ssize_t (*transfer)(const struct hmcdrv_ftp_cmdspec *ftp,
34 size_t *fsize);
35};
36
37static enum hmcdrv_ftp_cmdid hmcdrv_ftp_cmd_getid(const char *cmd, int len);
38static int hmcdrv_ftp_parse(char *cmd, struct hmcdrv_ftp_cmdspec *ftp);
39
40static const struct hmcdrv_ftp_ops *hmcdrv_ftp_funcs;
41static DEFINE_MUTEX(hmcdrv_ftp_mutex);
42static unsigned hmcdrv_ftp_refcnt;
43
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46
47
48
49static enum hmcdrv_ftp_cmdid hmcdrv_ftp_cmd_getid(const char *cmd, int len)
50{
51
52 struct hmcdrv_ftp_cmd_desc {
53 const char *str;
54 enum hmcdrv_ftp_cmdid cmd;
55 };
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65
66 static const struct hmcdrv_ftp_cmd_desc ftpcmds[7] = {
67
68 {.str = "get",
69 .cmd = HMCDRV_FTP_GET},
70 {.str = "dir",
71 .cmd = HMCDRV_FTP_DIR},
72 {.str = "delete",
73 .cmd = HMCDRV_FTP_DELETE},
74 {.str = "nls",
75 .cmd = HMCDRV_FTP_NLIST},
76 {.str = "put",
77 .cmd = HMCDRV_FTP_PUT},
78 {.str = "append",
79 .cmd = HMCDRV_FTP_APPEND},
80 {.str = NULL}
81 };
82
83 const struct hmcdrv_ftp_cmd_desc *pdesc;
84
85 u16 crc = 0xffffU;
86
87 if (len == 0)
88 return HMCDRV_FTP_NOOP;
89
90 crc = crc16(crc, cmd, len);
91 pdesc = ftpcmds + (crc % ARRAY_SIZE(ftpcmds));
92 pr_debug("FTP command '%s' has CRC 0x%04x, at table pos. %lu\n",
93 cmd, crc, (crc % ARRAY_SIZE(ftpcmds)));
94
95 if (!pdesc->str || strncmp(pdesc->str, cmd, len))
96 return HMCDRV_FTP_NOOP;
97
98 pr_debug("FTP command '%s' found, with ID %d\n",
99 pdesc->str, pdesc->cmd);
100
101 return pdesc->cmd;
102}
103
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109
110
111static int hmcdrv_ftp_parse(char *cmd, struct hmcdrv_ftp_cmdspec *ftp)
112{
113 char *start;
114 int argc = 0;
115
116 ftp->id = HMCDRV_FTP_NOOP;
117 ftp->fname = NULL;
118
119 while (*cmd != '\0') {
120
121 while (isspace(*cmd))
122 ++cmd;
123
124 if (*cmd == '\0')
125 break;
126
127 start = cmd;
128
129 switch (argc) {
130 case 0:
131 while ((*cmd != '\0') && !isspace(*cmd))
132 ++cmd;
133 ftp->id = hmcdrv_ftp_cmd_getid(start, cmd - start);
134 break;
135 case 1:
136 while ((*cmd != '\0') && !iscntrl(*cmd))
137 ++cmd;
138 ftp->fname = start;
139
140 default:
141 *cmd = '\0';
142 break;
143 }
144
145 ++argc;
146 }
147
148 if (!ftp->fname || (ftp->id == HMCDRV_FTP_NOOP))
149 return -EINVAL;
150
151 return 0;
152}
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159
160ssize_t hmcdrv_ftp_do(const struct hmcdrv_ftp_cmdspec *ftp)
161{
162 ssize_t len;
163
164 mutex_lock(&hmcdrv_ftp_mutex);
165
166 if (hmcdrv_ftp_funcs && hmcdrv_ftp_refcnt) {
167 pr_debug("starting transfer, cmd %d for '%s' at %lld with %zd bytes\n",
168 ftp->id, ftp->fname, (long long) ftp->ofs, ftp->len);
169 len = hmcdrv_cache_cmd(ftp, hmcdrv_ftp_funcs->transfer);
170 } else {
171 len = -ENXIO;
172 }
173
174 mutex_unlock(&hmcdrv_ftp_mutex);
175 return len;
176}
177EXPORT_SYMBOL(hmcdrv_ftp_do);
178
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182
183
184int hmcdrv_ftp_probe(void)
185{
186 int rc;
187
188 struct hmcdrv_ftp_cmdspec ftp = {
189 .id = HMCDRV_FTP_NOOP,
190 .ofs = 0,
191 .fname = "",
192 .len = PAGE_SIZE
193 };
194
195 ftp.buf = (void *) get_zeroed_page(GFP_KERNEL | GFP_DMA);
196
197 if (!ftp.buf)
198 return -ENOMEM;
199
200 rc = hmcdrv_ftp_startup();
201
202 if (rc)
203 goto out;
204
205 rc = hmcdrv_ftp_do(&ftp);
206 hmcdrv_ftp_shutdown();
207
208 switch (rc) {
209 case -ENOENT:
210 case -EBUSY:
211 rc = 0;
212 break;
213 default:
214 if (rc > 0)
215 rc = 0;
216 break;
217 }
218out:
219 free_page((unsigned long) ftp.buf);
220 return rc;
221}
222EXPORT_SYMBOL(hmcdrv_ftp_probe);
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235
236ssize_t hmcdrv_ftp_cmd(char __kernel *cmd, loff_t offset,
237 char __user *buf, size_t len)
238{
239 int order;
240
241 struct hmcdrv_ftp_cmdspec ftp = {.len = len, .ofs = offset};
242 ssize_t retlen = hmcdrv_ftp_parse(cmd, &ftp);
243
244 if (retlen)
245 return retlen;
246
247 order = get_order(ftp.len);
248 ftp.buf = (void *) __get_free_pages(GFP_KERNEL | GFP_DMA, order);
249
250 if (!ftp.buf)
251 return -ENOMEM;
252
253 switch (ftp.id) {
254 case HMCDRV_FTP_DIR:
255 case HMCDRV_FTP_NLIST:
256 case HMCDRV_FTP_GET:
257 retlen = hmcdrv_ftp_do(&ftp);
258
259 if ((retlen >= 0) &&
260 copy_to_user(buf, ftp.buf, retlen))
261 retlen = -EFAULT;
262 break;
263
264 case HMCDRV_FTP_PUT:
265 case HMCDRV_FTP_APPEND:
266 if (!copy_from_user(ftp.buf, buf, ftp.len))
267 retlen = hmcdrv_ftp_do(&ftp);
268 else
269 retlen = -EFAULT;
270 break;
271
272 case HMCDRV_FTP_DELETE:
273 retlen = hmcdrv_ftp_do(&ftp);
274 break;
275
276 default:
277 retlen = -EOPNOTSUPP;
278 break;
279 }
280
281 free_pages((unsigned long) ftp.buf, order);
282 return retlen;
283}
284
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289
290
291int hmcdrv_ftp_startup(void)
292{
293 static const struct hmcdrv_ftp_ops hmcdrv_ftp_zvm = {
294 .startup = diag_ftp_startup,
295 .shutdown = diag_ftp_shutdown,
296 .transfer = diag_ftp_cmd
297 };
298
299 static const struct hmcdrv_ftp_ops hmcdrv_ftp_lpar = {
300 .startup = sclp_ftp_startup,
301 .shutdown = sclp_ftp_shutdown,
302 .transfer = sclp_ftp_cmd
303 };
304
305 int rc = 0;
306
307 mutex_lock(&hmcdrv_ftp_mutex);
308
309 if (hmcdrv_ftp_refcnt == 0) {
310 if (MACHINE_IS_VM)
311 hmcdrv_ftp_funcs = &hmcdrv_ftp_zvm;
312 else if (MACHINE_IS_LPAR || MACHINE_IS_KVM)
313 hmcdrv_ftp_funcs = &hmcdrv_ftp_lpar;
314 else
315 rc = -EOPNOTSUPP;
316
317 if (hmcdrv_ftp_funcs)
318 rc = hmcdrv_ftp_funcs->startup();
319 }
320
321 if (!rc)
322 ++hmcdrv_ftp_refcnt;
323
324 mutex_unlock(&hmcdrv_ftp_mutex);
325 return rc;
326}
327EXPORT_SYMBOL(hmcdrv_ftp_startup);
328
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331
332
333void hmcdrv_ftp_shutdown(void)
334{
335 mutex_lock(&hmcdrv_ftp_mutex);
336 --hmcdrv_ftp_refcnt;
337
338 if ((hmcdrv_ftp_refcnt == 0) && hmcdrv_ftp_funcs)
339 hmcdrv_ftp_funcs->shutdown();
340
341 mutex_unlock(&hmcdrv_ftp_mutex);
342}
343EXPORT_SYMBOL(hmcdrv_ftp_shutdown);
344