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, 2009
   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/compat.h>
  16 #include <asm/ccwdev.h>
  17 #include "zfcp_def.h"
  18 #include "zfcp_ext.h"
  19 #include "zfcp_fsf.h"
  20
  21 #define ZFCP_CFDC_CMND_DOWNLOAD_NORMAL          0x00010001
  22 #define ZFCP_CFDC_CMND_DOWNLOAD_FORCE           0x00010101
  23 #define ZFCP_CFDC_CMND_FULL_ACCESS              0x00000201
  24 #define ZFCP_CFDC_CMND_RESTRICTED_ACCESS        0x00000401
  25 #define ZFCP_CFDC_CMND_UPLOAD                   0x00010002
  26
  27 #define ZFCP_CFDC_DOWNLOAD                      0x00000001
  28 #define ZFCP_CFDC_UPLOAD                        0x00000002
  29 #define ZFCP_CFDC_WITH_CONTROL_FILE             0x00010000
  30
  31 #define ZFCP_CFDC_IOC_MAGIC                     0xDD
  32 #define ZFCP_CFDC_IOC \
  33         _IOWR(ZFCP_CFDC_IOC_MAGIC, 0, struct zfcp_cfdc_data)
  34
  35 /**
  36  * struct zfcp_cfdc_data - data for ioctl cfdc interface
  37  * @signature: request signature
  38  * @devno: FCP adapter device number
  39  * @command: command code
  40  * @fsf_status: returns status of FSF command to userspace
  41  * @fsf_status_qual: returned to userspace
  42  * @payloads: access conflicts list
  43  * @control_file: access control table
  44  */
  45 struct zfcp_cfdc_data {
  46         u32 signature;
  47         u32 devno;
  48         u32 command;
  49         u32 fsf_status;
  50         u8  fsf_status_qual[FSF_STATUS_QUALIFIER_SIZE];
  51         u8  payloads[256];
  52         u8  control_file[0];
  53 };
  54
  55 static int zfcp_cfdc_copy_from_user(struct scatterlist *sg,
  56                                     void __user *user_buffer)
  57 {
  58         unsigned int length;
  59         unsigned int size = ZFCP_CFDC_MAX_SIZE;
  60
  61         while (size) {
  62                 length = min((unsigned int)size, sg->length);
  63                 if (copy_from_user(sg_virt(sg++), user_buffer, length))
  64                         return -EFAULT;
  65                 user_buffer += length;
  66                 size -= length;
  67         }
  68         return 0;
  69 }
  70
  71 static int zfcp_cfdc_copy_to_user(void __user  *user_buffer,
  72                                   struct scatterlist *sg)
  73 {
  74         unsigned int length;
  75         unsigned int size = ZFCP_CFDC_MAX_SIZE;
  76
  77         while (size) {
  78                 length = min((unsigned int) size, sg->length);
  79                 if (copy_to_user(user_buffer, sg_virt(sg++), length))
  80                         return -EFAULT;
  81                 user_buffer += length;
  82                 size -= length;
  83         }
  84         return 0;
  85 }
  86
  87 static struct zfcp_adapter *zfcp_cfdc_get_adapter(u32 devno)
  88 {
  89         char busid[9];
  90         struct ccw_device *cdev;
  91         struct zfcp_adapter *adapter;
  92
  93         snprintf(busid, sizeof(busid), "0.0.%04x", devno);
  94         cdev = get_ccwdev_by_busid(&zfcp_ccw_driver, busid);
  95         if (!cdev)
  96                 return NULL;
  97
  98         adapter = zfcp_ccw_adapter_by_cdev(cdev);
  99
 100         put_device(&cdev->dev);
 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 arg)
 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         if (is_compat_task())
 180                 data_user = compat_ptr(arg);
 181         else
 182                 data_user = (void __user *)arg;
 183
 184         if (!data_user)
 185                 return -EINVAL;
 186
 187         fsf_cfdc = kmalloc(sizeof(struct zfcp_fsf_cfdc), GFP_KERNEL);
 188         if (!fsf_cfdc)
 189                 return -ENOMEM;
 190
 191         data = kmalloc(sizeof(struct zfcp_cfdc_data), GFP_KERNEL);
 192         if (!data) {
 193                 retval = -ENOMEM;
 194                 goto no_mem_sense;
 195         }
 196
 197         retval = copy_from_user(data, data_user, sizeof(*data));
 198         if (retval) {
 199                 retval = -EFAULT;
 200                 goto free_buffer;
 201         }
 202
 203         if (data->signature != 0xCFDCACDF) {
 204                 retval = -EINVAL;
 205                 goto free_buffer;
 206         }
 207
 208         retval = zfcp_cfdc_set_fsf(fsf_cfdc, data->command);
 209
 210         adapter = zfcp_cfdc_get_adapter(data->devno);
 211         if (!adapter) {
 212                 retval = -ENXIO;
 213                 goto free_buffer;
 214         }
 215
 216         retval = zfcp_cfdc_sg_setup(data->command, fsf_cfdc->sg,
 217                                     data_user->control_file);
 218         if (retval)
 219                 goto adapter_put;
 220         req = zfcp_fsf_control_file(adapter, fsf_cfdc);
 221         if (IS_ERR(req)) {
 222                 retval = PTR_ERR(req);
 223                 goto free_sg;
 224         }
 225
 226         if (req->status & ZFCP_STATUS_FSFREQ_ERROR) {
 227                 retval = -ENXIO;
 228                 goto free_fsf;
 229         }
 230
 231         zfcp_cfdc_req_to_sense(data, req);
 232         retval = copy_to_user(data_user, data, sizeof(*data_user));
 233         if (retval) {
 234                 retval = -EFAULT;
 235                 goto free_fsf;
 236         }
 237
 238         if (data->command & ZFCP_CFDC_UPLOAD)
 239                 retval = zfcp_cfdc_copy_to_user(&data_user->control_file,
 240                                                 fsf_cfdc->sg);
 241
 242  free_fsf:
 243         zfcp_fsf_req_free(req);
 244  free_sg:
 245         zfcp_sg_free_table(fsf_cfdc->sg, ZFCP_CFDC_PAGES);
 246  adapter_put:
 247         zfcp_ccw_adapter_put(adapter);
 248  free_buffer:
 249         kfree(data);
 250  no_mem_sense:
 251         kfree(fsf_cfdc);
 252         return retval;
 253 }
 254
 255 static const struct file_operations zfcp_cfdc_fops = {
 256         .unlocked_ioctl = zfcp_cfdc_dev_ioctl,
 257 #ifdef CONFIG_COMPAT
 258         .compat_ioctl = zfcp_cfdc_dev_ioctl
 259 #endif
 260 };
 261
 262 struct miscdevice zfcp_cfdc_misc = {
 263         .minor = MISC_DYNAMIC_MINOR,
 264         .name = "zfcp_cfdc",
 265         .fops = &zfcp_cfdc_fops,
 266 };