Merge git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending
[cascardo/linux.git] / drivers / s390 / scsi / zfcp_cfdc.c
1 /*
2  * zfcp device driver
3  *
4  * Userspace interface for accessing the
5  * Access Control Lists / Control File Data Channel;
6  * handling of response code and states for ports and LUNs.
7  *
8  * Copyright IBM Corp. 2008, 2010
9  */
10
11 #define KMSG_COMPONENT "zfcp"
12 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
13
14 #include <linux/compat.h>
15 #include <linux/slab.h>
16 #include <linux/types.h>
17 #include <linux/miscdevice.h>
18 #include <asm/compat.h>
19 #include <asm/ccwdev.h>
20 #include "zfcp_def.h"
21 #include "zfcp_ext.h"
22 #include "zfcp_fsf.h"
23
24 #define ZFCP_CFDC_CMND_DOWNLOAD_NORMAL          0x00010001
25 #define ZFCP_CFDC_CMND_DOWNLOAD_FORCE           0x00010101
26 #define ZFCP_CFDC_CMND_FULL_ACCESS              0x00000201
27 #define ZFCP_CFDC_CMND_RESTRICTED_ACCESS        0x00000401
28 #define ZFCP_CFDC_CMND_UPLOAD                   0x00010002
29
30 #define ZFCP_CFDC_DOWNLOAD                      0x00000001
31 #define ZFCP_CFDC_UPLOAD                        0x00000002
32 #define ZFCP_CFDC_WITH_CONTROL_FILE             0x00010000
33
34 #define ZFCP_CFDC_IOC_MAGIC                     0xDD
35 #define ZFCP_CFDC_IOC \
36         _IOWR(ZFCP_CFDC_IOC_MAGIC, 0, struct zfcp_cfdc_data)
37
38 /**
39  * struct zfcp_cfdc_data - data for ioctl cfdc interface
40  * @signature: request signature
41  * @devno: FCP adapter device number
42  * @command: command code
43  * @fsf_status: returns status of FSF command to userspace
44  * @fsf_status_qual: returned to userspace
45  * @payloads: access conflicts list
46  * @control_file: access control table
47  */
48 struct zfcp_cfdc_data {
49         u32 signature;
50         u32 devno;
51         u32 command;
52         u32 fsf_status;
53         u8  fsf_status_qual[FSF_STATUS_QUALIFIER_SIZE];
54         u8  payloads[256];
55         u8  control_file[0];
56 };
57
58 static int zfcp_cfdc_copy_from_user(struct scatterlist *sg,
59                                     void __user *user_buffer)
60 {
61         unsigned int length;
62         unsigned int size = ZFCP_CFDC_MAX_SIZE;
63
64         while (size) {
65                 length = min((unsigned int)size, sg->length);
66                 if (copy_from_user(sg_virt(sg++), user_buffer, length))
67                         return -EFAULT;
68                 user_buffer += length;
69                 size -= length;
70         }
71         return 0;
72 }
73
74 static int zfcp_cfdc_copy_to_user(void __user  *user_buffer,
75                                   struct scatterlist *sg)
76 {
77         unsigned int length;
78         unsigned int size = ZFCP_CFDC_MAX_SIZE;
79
80         while (size) {
81                 length = min((unsigned int) size, sg->length);
82                 if (copy_to_user(user_buffer, sg_virt(sg++), length))
83                         return -EFAULT;
84                 user_buffer += length;
85                 size -= length;
86         }
87         return 0;
88 }
89
90 static struct zfcp_adapter *zfcp_cfdc_get_adapter(u32 devno)
91 {
92         char busid[9];
93         struct ccw_device *cdev;
94         struct zfcp_adapter *adapter;
95
96         snprintf(busid, sizeof(busid), "0.0.%04x", devno);
97         cdev = get_ccwdev_by_busid(&zfcp_ccw_driver, busid);
98         if (!cdev)
99                 return NULL;
100
101         adapter = zfcp_ccw_adapter_by_cdev(cdev);
102
103         put_device(&cdev->dev);
104         return adapter;
105 }
106
107 static int zfcp_cfdc_set_fsf(struct zfcp_fsf_cfdc *fsf_cfdc, int command)
108 {
109         switch (command) {
110         case ZFCP_CFDC_CMND_DOWNLOAD_NORMAL:
111                 fsf_cfdc->command = FSF_QTCB_DOWNLOAD_CONTROL_FILE;
112                 fsf_cfdc->option = FSF_CFDC_OPTION_NORMAL_MODE;
113                 break;
114         case ZFCP_CFDC_CMND_DOWNLOAD_FORCE:
115                 fsf_cfdc->command = FSF_QTCB_DOWNLOAD_CONTROL_FILE;
116                 fsf_cfdc->option = FSF_CFDC_OPTION_FORCE;
117                 break;
118         case ZFCP_CFDC_CMND_FULL_ACCESS:
119                 fsf_cfdc->command = FSF_QTCB_DOWNLOAD_CONTROL_FILE;
120                 fsf_cfdc->option = FSF_CFDC_OPTION_FULL_ACCESS;
121                 break;
122         case ZFCP_CFDC_CMND_RESTRICTED_ACCESS:
123                 fsf_cfdc->command = FSF_QTCB_DOWNLOAD_CONTROL_FILE;
124                 fsf_cfdc->option = FSF_CFDC_OPTION_RESTRICTED_ACCESS;
125                 break;
126         case ZFCP_CFDC_CMND_UPLOAD:
127                 fsf_cfdc->command = FSF_QTCB_UPLOAD_CONTROL_FILE;
128                 fsf_cfdc->option = 0;
129                 break;
130         default:
131                 return -EINVAL;
132         }
133
134         return 0;
135 }
136
137 static int zfcp_cfdc_sg_setup(int command, struct scatterlist *sg,
138                               u8 __user *control_file)
139 {
140         int retval;
141         retval = zfcp_sg_setup_table(sg, ZFCP_CFDC_PAGES);
142         if (retval)
143                 return retval;
144
145         sg[ZFCP_CFDC_PAGES - 1].length = ZFCP_CFDC_MAX_SIZE % PAGE_SIZE;
146
147         if (command & ZFCP_CFDC_WITH_CONTROL_FILE &&
148             command & ZFCP_CFDC_DOWNLOAD) {
149                 retval = zfcp_cfdc_copy_from_user(sg, control_file);
150                 if (retval) {
151                         zfcp_sg_free_table(sg, ZFCP_CFDC_PAGES);
152                         return -EFAULT;
153                 }
154         }
155
156         return 0;
157 }
158
159 static void zfcp_cfdc_req_to_sense(struct zfcp_cfdc_data *data,
160                                    struct zfcp_fsf_req *req)
161 {
162         data->fsf_status = req->qtcb->header.fsf_status;
163         memcpy(&data->fsf_status_qual, &req->qtcb->header.fsf_status_qual,
164                sizeof(union fsf_status_qual));
165         memcpy(&data->payloads, &req->qtcb->bottom.support.els,
166                sizeof(req->qtcb->bottom.support.els));
167 }
168
169 static long zfcp_cfdc_dev_ioctl(struct file *file, unsigned int command,
170                                 unsigned long arg)
171 {
172         struct zfcp_cfdc_data *data;
173         struct zfcp_cfdc_data __user *data_user;
174         struct zfcp_adapter *adapter;
175         struct zfcp_fsf_req *req;
176         struct zfcp_fsf_cfdc *fsf_cfdc;
177         int retval;
178
179         if (command != ZFCP_CFDC_IOC)
180                 return -ENOTTY;
181
182         if (is_compat_task())
183                 data_user = compat_ptr(arg);
184         else
185                 data_user = (void __user *)arg;
186
187         if (!data_user)
188                 return -EINVAL;
189
190         fsf_cfdc = kmalloc(sizeof(struct zfcp_fsf_cfdc), GFP_KERNEL);
191         if (!fsf_cfdc)
192                 return -ENOMEM;
193
194         data = memdup_user(data_user, sizeof(*data_user));
195         if (IS_ERR(data)) {
196                 retval = PTR_ERR(data);
197                 goto no_mem_sense;
198         }
199
200         if (data->signature != 0xCFDCACDF) {
201                 retval = -EINVAL;
202                 goto free_buffer;
203         }
204
205         retval = zfcp_cfdc_set_fsf(fsf_cfdc, data->command);
206
207         adapter = zfcp_cfdc_get_adapter(data->devno);
208         if (!adapter) {
209                 retval = -ENXIO;
210                 goto free_buffer;
211         }
212
213         retval = zfcp_cfdc_sg_setup(data->command, fsf_cfdc->sg,
214                                     data_user->control_file);
215         if (retval)
216                 goto adapter_put;
217         req = zfcp_fsf_control_file(adapter, fsf_cfdc);
218         if (IS_ERR(req)) {
219                 retval = PTR_ERR(req);
220                 goto free_sg;
221         }
222
223         if (req->status & ZFCP_STATUS_FSFREQ_ERROR) {
224                 retval = -ENXIO;
225                 goto free_fsf;
226         }
227
228         zfcp_cfdc_req_to_sense(data, req);
229         retval = copy_to_user(data_user, data, sizeof(*data_user));
230         if (retval) {
231                 retval = -EFAULT;
232                 goto free_fsf;
233         }
234
235         if (data->command & ZFCP_CFDC_UPLOAD)
236                 retval = zfcp_cfdc_copy_to_user(&data_user->control_file,
237                                                 fsf_cfdc->sg);
238
239  free_fsf:
240         zfcp_fsf_req_free(req);
241  free_sg:
242         zfcp_sg_free_table(fsf_cfdc->sg, ZFCP_CFDC_PAGES);
243  adapter_put:
244         zfcp_ccw_adapter_put(adapter);
245  free_buffer:
246         kfree(data);
247  no_mem_sense:
248         kfree(fsf_cfdc);
249         return retval;
250 }
251
252 static const struct file_operations zfcp_cfdc_fops = {
253         .open = nonseekable_open,
254         .unlocked_ioctl = zfcp_cfdc_dev_ioctl,
255 #ifdef CONFIG_COMPAT
256         .compat_ioctl = zfcp_cfdc_dev_ioctl,
257 #endif
258         .llseek = no_llseek,
259 };
260
261 struct miscdevice zfcp_cfdc_misc = {
262         .minor = MISC_DYNAMIC_MINOR,
263         .name = "zfcp_cfdc",
264         .fops = &zfcp_cfdc_fops,
265 };
266
267 /**
268  * zfcp_cfdc_adapter_access_changed - Process change in adapter ACT
269  * @adapter: Adapter where the Access Control Table (ACT) changed
270  *
271  * After a change in the adapter ACT, check if access to any
272  * previously denied resources is now possible.
273  */
274 void zfcp_cfdc_adapter_access_changed(struct zfcp_adapter *adapter)
275 {
276         unsigned long flags;
277         struct zfcp_port *port;
278         struct scsi_device *sdev;
279         struct zfcp_scsi_dev *zfcp_sdev;
280         int status;
281
282         if (adapter->connection_features & FSF_FEATURE_NPIV_MODE)
283                 return;
284
285         read_lock_irqsave(&adapter->port_list_lock, flags);
286         list_for_each_entry(port, &adapter->port_list, list) {
287                 status = atomic_read(&port->status);
288                 if ((status & ZFCP_STATUS_COMMON_ACCESS_DENIED) ||
289                     (status & ZFCP_STATUS_COMMON_ACCESS_BOXED))
290                         zfcp_erp_port_reopen(port,
291                                              ZFCP_STATUS_COMMON_ERP_FAILED,
292                                              "cfaac_1");
293         }
294         read_unlock_irqrestore(&adapter->port_list_lock, flags);
295
296         shost_for_each_device(sdev, adapter->scsi_host) {
297                 zfcp_sdev = sdev_to_zfcp(sdev);
298                 status = atomic_read(&zfcp_sdev->status);
299                 if ((status & ZFCP_STATUS_COMMON_ACCESS_DENIED) ||
300                     (status & ZFCP_STATUS_COMMON_ACCESS_BOXED))
301                         zfcp_erp_lun_reopen(sdev,
302                                             ZFCP_STATUS_COMMON_ERP_FAILED,
303                                             "cfaac_2");
304         }
305 }
306
307 static void zfcp_act_eval_err(struct zfcp_adapter *adapter, u32 table)
308 {
309         u16 subtable = table >> 16;
310         u16 rule = table & 0xffff;
311         const char *act_type[] = { "unknown", "OS", "WWPN", "DID", "LUN" };
312
313         if (subtable && subtable < ARRAY_SIZE(act_type))
314                 dev_warn(&adapter->ccw_device->dev,
315                          "Access denied according to ACT rule type %s, "
316                          "rule %d\n", act_type[subtable], rule);
317 }
318
319 /**
320  * zfcp_cfdc_port_denied - Process "access denied" for port
321  * @port: The port where the access has been denied
322  * @qual: The FSF status qualifier for the access denied FSF status
323  */
324 void zfcp_cfdc_port_denied(struct zfcp_port *port,
325                            union fsf_status_qual *qual)
326 {
327         dev_warn(&port->adapter->ccw_device->dev,
328                  "Access denied to port 0x%016Lx\n",
329                  (unsigned long long)port->wwpn);
330
331         zfcp_act_eval_err(port->adapter, qual->halfword[0]);
332         zfcp_act_eval_err(port->adapter, qual->halfword[1]);
333         zfcp_erp_set_port_status(port,
334                                  ZFCP_STATUS_COMMON_ERP_FAILED |
335                                  ZFCP_STATUS_COMMON_ACCESS_DENIED);
336 }
337
338 /**
339  * zfcp_cfdc_lun_denied - Process "access denied" for LUN
340  * @sdev: The SCSI device / LUN where the access has been denied
341  * @qual: The FSF status qualifier for the access denied FSF status
342  */
343 void zfcp_cfdc_lun_denied(struct scsi_device *sdev,
344                           union fsf_status_qual *qual)
345 {
346         struct zfcp_scsi_dev *zfcp_sdev = sdev_to_zfcp(sdev);
347
348         dev_warn(&zfcp_sdev->port->adapter->ccw_device->dev,
349                  "Access denied to LUN 0x%016Lx on port 0x%016Lx\n",
350                  zfcp_scsi_dev_lun(sdev),
351                  (unsigned long long)zfcp_sdev->port->wwpn);
352         zfcp_act_eval_err(zfcp_sdev->port->adapter, qual->halfword[0]);
353         zfcp_act_eval_err(zfcp_sdev->port->adapter, qual->halfword[1]);
354         zfcp_erp_set_lun_status(sdev,
355                                 ZFCP_STATUS_COMMON_ERP_FAILED |
356                                 ZFCP_STATUS_COMMON_ACCESS_DENIED);
357
358         atomic_clear_mask(ZFCP_STATUS_LUN_SHARED, &zfcp_sdev->status);
359         atomic_clear_mask(ZFCP_STATUS_LUN_READONLY, &zfcp_sdev->status);
360 }
361
362 /**
363  * zfcp_cfdc_lun_shrng_vltn - Evaluate LUN sharing violation status
364  * @sdev: The LUN / SCSI device where sharing violation occurred
365  * @qual: The FSF status qualifier from the LUN sharing violation
366  */
367 void zfcp_cfdc_lun_shrng_vltn(struct scsi_device *sdev,
368                               union fsf_status_qual *qual)
369 {
370         struct zfcp_scsi_dev *zfcp_sdev = sdev_to_zfcp(sdev);
371
372         if (qual->word[0])
373                 dev_warn(&zfcp_sdev->port->adapter->ccw_device->dev,
374                          "LUN 0x%Lx on port 0x%Lx is already in "
375                          "use by CSS%d, MIF Image ID %x\n",
376                          zfcp_scsi_dev_lun(sdev),
377                          (unsigned long long)zfcp_sdev->port->wwpn,
378                          qual->fsf_queue_designator.cssid,
379                          qual->fsf_queue_designator.hla);
380         else
381                 zfcp_act_eval_err(zfcp_sdev->port->adapter, qual->word[2]);
382
383         zfcp_erp_set_lun_status(sdev,
384                                 ZFCP_STATUS_COMMON_ERP_FAILED |
385                                 ZFCP_STATUS_COMMON_ACCESS_DENIED);
386         atomic_clear_mask(ZFCP_STATUS_LUN_SHARED, &zfcp_sdev->status);
387         atomic_clear_mask(ZFCP_STATUS_LUN_READONLY, &zfcp_sdev->status);
388 }
389
390 /**
391  * zfcp_cfdc_open_lun_eval - Eval access ctrl. status for successful "open lun"
392  * @sdev: The SCSI device / LUN where to evaluate the status
393  * @bottom: The qtcb bottom with the status from the "open lun"
394  *
395  * Returns: 0 if LUN is usable, -EACCES if the access control table
396  *          reports an unsupported configuration.
397  */
398 int zfcp_cfdc_open_lun_eval(struct scsi_device *sdev,
399                             struct fsf_qtcb_bottom_support *bottom)
400 {
401         int shared, rw;
402         struct zfcp_scsi_dev *zfcp_sdev = sdev_to_zfcp(sdev);
403         struct zfcp_adapter *adapter = zfcp_sdev->port->adapter;
404
405         if ((adapter->connection_features & FSF_FEATURE_NPIV_MODE) ||
406             !(adapter->adapter_features & FSF_FEATURE_LUN_SHARING) ||
407             zfcp_ccw_priv_sch(adapter))
408                 return 0;
409
410         shared = !(bottom->lun_access_info & FSF_UNIT_ACCESS_EXCLUSIVE);
411         rw = (bottom->lun_access_info & FSF_UNIT_ACCESS_OUTBOUND_TRANSFER);
412
413         if (shared)
414                 atomic_set_mask(ZFCP_STATUS_LUN_SHARED, &zfcp_sdev->status);
415
416         if (!rw) {
417                 atomic_set_mask(ZFCP_STATUS_LUN_READONLY, &zfcp_sdev->status);
418                 dev_info(&adapter->ccw_device->dev, "SCSI device at LUN "
419                          "0x%016Lx on port 0x%016Lx opened read-only\n",
420                          zfcp_scsi_dev_lun(sdev),
421                          (unsigned long long)zfcp_sdev->port->wwpn);
422         }
423
424         if (!shared && !rw) {
425                 dev_err(&adapter->ccw_device->dev, "Exclusive read-only access "
426                         "not supported (LUN 0x%016Lx, port 0x%016Lx)\n",
427                         zfcp_scsi_dev_lun(sdev),
428                         (unsigned long long)zfcp_sdev->port->wwpn);
429                 zfcp_erp_set_lun_status(sdev, ZFCP_STATUS_COMMON_ERP_FAILED);
430                 zfcp_erp_lun_shutdown(sdev, 0, "fsouh_6");
431                 return -EACCES;
432         }
433
434         if (shared && rw) {
435                 dev_err(&adapter->ccw_device->dev,
436                         "Shared read-write access not supported "
437                         "(LUN 0x%016Lx, port 0x%016Lx)\n",
438                         zfcp_scsi_dev_lun(sdev),
439                         (unsigned long long)zfcp_sdev->port->wwpn);
440                 zfcp_erp_set_lun_status(sdev, ZFCP_STATUS_COMMON_ERP_FAILED);
441                 zfcp_erp_lun_shutdown(sdev, 0, "fsosh_8");
442                 return -EACCES;
443         }
444
445         return 0;
446 }