Merge branch 'topic/kmemtrace' of git://git.kernel.org/pub/scm/linux/kernel/git/penbe...
[linux-2.6] / 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  *
7  * Copyright IBM Corporation 2008
8  */
9
10 #define KMSG_COMPONENT "zfcp"
11 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
12
13 #include <linux/types.h>
14 #include <linux/miscdevice.h>
15 #include <asm/ccwdev.h>
16 #include "zfcp_def.h"
17 #include "zfcp_ext.h"
18 #include "zfcp_fsf.h"
19
20 #define ZFCP_CFDC_CMND_DOWNLOAD_NORMAL          0x00010001
21 #define ZFCP_CFDC_CMND_DOWNLOAD_FORCE           0x00010101
22 #define ZFCP_CFDC_CMND_FULL_ACCESS              0x00000201
23 #define ZFCP_CFDC_CMND_RESTRICTED_ACCESS        0x00000401
24 #define ZFCP_CFDC_CMND_UPLOAD                   0x00010002
25
26 #define ZFCP_CFDC_DOWNLOAD                      0x00000001
27 #define ZFCP_CFDC_UPLOAD                        0x00000002
28 #define ZFCP_CFDC_WITH_CONTROL_FILE             0x00010000
29
30 #define ZFCP_CFDC_IOC_MAGIC                     0xDD
31 #define ZFCP_CFDC_IOC \
32         _IOWR(ZFCP_CFDC_IOC_MAGIC, 0, struct zfcp_cfdc_data)
33
34 /**
35  * struct zfcp_cfdc_data - data for ioctl cfdc interface
36  * @signature: request signature
37  * @devno: FCP adapter device number
38  * @command: command code
39  * @fsf_status: returns status of FSF command to userspace
40  * @fsf_status_qual: returned to userspace
41  * @payloads: access conflicts list
42  * @control_file: access control table
43  */
44 struct zfcp_cfdc_data {
45         u32 signature;
46         u32 devno;
47         u32 command;
48         u32 fsf_status;
49         u8  fsf_status_qual[FSF_STATUS_QUALIFIER_SIZE];
50         u8  payloads[256];
51         u8  control_file[0];
52 };
53
54 static int zfcp_cfdc_copy_from_user(struct scatterlist *sg,
55                                     void __user *user_buffer)
56 {
57         unsigned int length;
58         unsigned int size = ZFCP_CFDC_MAX_SIZE;
59
60         while (size) {
61                 length = min((unsigned int)size, sg->length);
62                 if (copy_from_user(sg_virt(sg++), user_buffer, length))
63                         return -EFAULT;
64                 user_buffer += length;
65                 size -= length;
66         }
67         return 0;
68 }
69
70 static int zfcp_cfdc_copy_to_user(void __user  *user_buffer,
71                                   struct scatterlist *sg)
72 {
73         unsigned int length;
74         unsigned int size = ZFCP_CFDC_MAX_SIZE;
75
76         while (size) {
77                 length = min((unsigned int) size, sg->length);
78                 if (copy_to_user(user_buffer, sg_virt(sg++), length))
79                         return -EFAULT;
80                 user_buffer += length;
81                 size -= length;
82         }
83         return 0;
84 }
85
86 static struct zfcp_adapter *zfcp_cfdc_get_adapter(u32 devno)
87 {
88         struct zfcp_adapter *adapter = NULL, *cur_adapter;
89         struct ccw_dev_id dev_id;
90
91         read_lock_irq(&zfcp_data.config_lock);
92         list_for_each_entry(cur_adapter, &zfcp_data.adapter_list_head, list) {
93                 ccw_device_get_id(cur_adapter->ccw_device, &dev_id);
94                 if (dev_id.devno == devno) {
95                         adapter = cur_adapter;
96                         zfcp_adapter_get(adapter);
97                         break;
98                 }
99         }
100         read_unlock_irq(&zfcp_data.config_lock);
101         return adapter;
102 }
103
104 static int zfcp_cfdc_set_fsf(struct zfcp_fsf_cfdc *fsf_cfdc, int command)
105 {
106         switch (command) {
107         case ZFCP_CFDC_CMND_DOWNLOAD_NORMAL:
108                 fsf_cfdc->command = FSF_QTCB_DOWNLOAD_CONTROL_FILE;
109                 fsf_cfdc->option = FSF_CFDC_OPTION_NORMAL_MODE;
110                 break;
111         case ZFCP_CFDC_CMND_DOWNLOAD_FORCE:
112                 fsf_cfdc->command = FSF_QTCB_DOWNLOAD_CONTROL_FILE;
113                 fsf_cfdc->option = FSF_CFDC_OPTION_FORCE;
114                 break;
115         case ZFCP_CFDC_CMND_FULL_ACCESS:
116                 fsf_cfdc->command = FSF_QTCB_DOWNLOAD_CONTROL_FILE;
117                 fsf_cfdc->option = FSF_CFDC_OPTION_FULL_ACCESS;
118                 break;
119         case ZFCP_CFDC_CMND_RESTRICTED_ACCESS:
120                 fsf_cfdc->command = FSF_QTCB_DOWNLOAD_CONTROL_FILE;
121                 fsf_cfdc->option = FSF_CFDC_OPTION_RESTRICTED_ACCESS;
122                 break;
123         case ZFCP_CFDC_CMND_UPLOAD:
124                 fsf_cfdc->command = FSF_QTCB_UPLOAD_CONTROL_FILE;
125                 fsf_cfdc->option = 0;
126                 break;
127         default:
128                 return -EINVAL;
129         }
130
131         return 0;
132 }
133
134 static int zfcp_cfdc_sg_setup(int command, struct scatterlist *sg,
135                               u8 __user *control_file)
136 {
137         int retval;
138         retval = zfcp_sg_setup_table(sg, ZFCP_CFDC_PAGES);
139         if (retval)
140                 return retval;
141
142         sg[ZFCP_CFDC_PAGES - 1].length = ZFCP_CFDC_MAX_SIZE % PAGE_SIZE;
143
144         if (command & ZFCP_CFDC_WITH_CONTROL_FILE &&
145             command & ZFCP_CFDC_DOWNLOAD) {
146                 retval = zfcp_cfdc_copy_from_user(sg, control_file);
147                 if (retval) {
148                         zfcp_sg_free_table(sg, ZFCP_CFDC_PAGES);
149                         return -EFAULT;
150                 }
151         }
152
153         return 0;
154 }
155
156 static void zfcp_cfdc_req_to_sense(struct zfcp_cfdc_data *data,
157                                    struct zfcp_fsf_req *req)
158 {
159         data->fsf_status = req->qtcb->header.fsf_status;
160         memcpy(&data->fsf_status_qual, &req->qtcb->header.fsf_status_qual,
161                sizeof(union fsf_status_qual));
162         memcpy(&data->payloads, &req->qtcb->bottom.support.els,
163                sizeof(req->qtcb->bottom.support.els));
164 }
165
166 static long zfcp_cfdc_dev_ioctl(struct file *file, unsigned int command,
167                                 unsigned long buffer)
168 {
169         struct zfcp_cfdc_data *data;
170         struct zfcp_cfdc_data __user *data_user;
171         struct zfcp_adapter *adapter;
172         struct zfcp_fsf_req *req;
173         struct zfcp_fsf_cfdc *fsf_cfdc;
174         int retval;
175
176         if (command != ZFCP_CFDC_IOC)
177                 return -ENOTTY;
178
179         data_user = (void __user *) buffer;
180         if (!data_user)
181                 return -EINVAL;
182
183         fsf_cfdc = kmalloc(sizeof(struct zfcp_fsf_cfdc), GFP_KERNEL);
184         if (!fsf_cfdc)
185                 return -ENOMEM;
186
187         data = kmalloc(sizeof(struct zfcp_cfdc_data), GFP_KERNEL);
188         if (!data) {
189                 retval = -ENOMEM;
190                 goto no_mem_sense;
191         }
192
193         retval = copy_from_user(data, data_user, sizeof(*data));
194         if (retval) {
195                 retval = -EFAULT;
196                 goto free_buffer;
197         }
198
199         if (data->signature != 0xCFDCACDF) {
200                 retval = -EINVAL;
201                 goto free_buffer;
202         }
203
204         retval = zfcp_cfdc_set_fsf(fsf_cfdc, data->command);
205
206         adapter = zfcp_cfdc_get_adapter(data->devno);
207         if (!adapter) {
208                 retval = -ENXIO;
209                 goto free_buffer;
210         }
211
212         retval = zfcp_cfdc_sg_setup(data->command, fsf_cfdc->sg,
213                                     data_user->control_file);
214         if (retval)
215                 goto adapter_put;
216         req = zfcp_fsf_control_file(adapter, fsf_cfdc);
217         if (IS_ERR(req)) {
218                 retval = PTR_ERR(req);
219                 goto free_sg;
220         }
221
222         if (req->status & ZFCP_STATUS_FSFREQ_ERROR) {
223                 retval = -ENXIO;
224                 goto free_fsf;
225         }
226
227         zfcp_cfdc_req_to_sense(data, req);
228         retval = copy_to_user(data_user, data, sizeof(*data_user));
229         if (retval) {
230                 retval = -EFAULT;
231                 goto free_fsf;
232         }
233
234         if (data->command & ZFCP_CFDC_UPLOAD)
235                 retval = zfcp_cfdc_copy_to_user(&data_user->control_file,
236                                                 fsf_cfdc->sg);
237
238  free_fsf:
239         zfcp_fsf_req_free(req);
240  free_sg:
241         zfcp_sg_free_table(fsf_cfdc->sg, ZFCP_CFDC_PAGES);
242  adapter_put:
243         zfcp_adapter_put(adapter);
244  free_buffer:
245         kfree(data);
246  no_mem_sense:
247         kfree(fsf_cfdc);
248         return retval;
249 }
250
251 static const struct file_operations zfcp_cfdc_fops = {
252         .unlocked_ioctl = zfcp_cfdc_dev_ioctl,
253 #ifdef CONFIG_COMPAT
254         .compat_ioctl = zfcp_cfdc_dev_ioctl
255 #endif
256 };
257
258 struct miscdevice zfcp_cfdc_misc = {
259         .minor = MISC_DYNAMIC_MINOR,
260         .name = "zfcp_cfdc",
261         .fops = &zfcp_cfdc_fops,
262 };