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/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         char busid[9];
  89         struct ccw_device *cdev;
  90         struct zfcp_adapter *adapter;
  91
  92         snprintf(busid, sizeof(busid), "0.0.%04x", devno);
  93         cdev = get_ccwdev_by_busid(&zfcp_ccw_driver, busid);
  94         if (!cdev)
  95                 return NULL;
  96
  97         adapter = zfcp_ccw_adapter_by_cdev(cdev);
  98
  99         put_device(&cdev->dev);
 100         return adapter;
 101 }
 102
 103 static int zfcp_cfdc_set_fsf(struct zfcp_fsf_cfdc *fsf_cfdc, int command)
 104 {
 105         switch (command) {
 106         case ZFCP_CFDC_CMND_DOWNLOAD_NORMAL:
 107                 fsf_cfdc->command = FSF_QTCB_DOWNLOAD_CONTROL_FILE;
 108                 fsf_cfdc->option = FSF_CFDC_OPTION_NORMAL_MODE;
 109                 break;
 110         case ZFCP_CFDC_CMND_DOWNLOAD_FORCE:
 111                 fsf_cfdc->command = FSF_QTCB_DOWNLOAD_CONTROL_FILE;
 112                 fsf_cfdc->option = FSF_CFDC_OPTION_FORCE;
 113                 break;
 114         case ZFCP_CFDC_CMND_FULL_ACCESS:
 115                 fsf_cfdc->command = FSF_QTCB_DOWNLOAD_CONTROL_FILE;
 116                 fsf_cfdc->option = FSF_CFDC_OPTION_FULL_ACCESS;
 117                 break;
 118         case ZFCP_CFDC_CMND_RESTRICTED_ACCESS:
 119                 fsf_cfdc->command = FSF_QTCB_DOWNLOAD_CONTROL_FILE;
 120                 fsf_cfdc->option = FSF_CFDC_OPTION_RESTRICTED_ACCESS;
 121                 break;
 122         case ZFCP_CFDC_CMND_UPLOAD:
 123                 fsf_cfdc->command = FSF_QTCB_UPLOAD_CONTROL_FILE;
 124                 fsf_cfdc->option = 0;
 125                 break;
 126         default:
 127                 return -EINVAL;
 128         }
 129
 130         return 0;
 131 }
 132
 133 static int zfcp_cfdc_sg_setup(int command, struct scatterlist *sg,
 134                               u8 __user *control_file)
 135 {
 136         int retval;
 137         retval = zfcp_sg_setup_table(sg, ZFCP_CFDC_PAGES);
 138         if (retval)
 139                 return retval;
 140
 141         sg[ZFCP_CFDC_PAGES - 1].length = ZFCP_CFDC_MAX_SIZE % PAGE_SIZE;
 142
 143         if (command & ZFCP_CFDC_WITH_CONTROL_FILE &&
 144             command & ZFCP_CFDC_DOWNLOAD) {
 145                 retval = zfcp_cfdc_copy_from_user(sg, control_file);
 146                 if (retval) {
 147                         zfcp_sg_free_table(sg, ZFCP_CFDC_PAGES);
 148                         return -EFAULT;
 149                 }
 150         }
 151
 152         return 0;
 153 }
 154
 155 static void zfcp_cfdc_req_to_sense(struct zfcp_cfdc_data *data,
 156                                    struct zfcp_fsf_req *req)
 157 {
 158         data->fsf_status = req->qtcb->header.fsf_status;
 159         memcpy(&data->fsf_status_qual, &req->qtcb->header.fsf_status_qual,
 160                sizeof(union fsf_status_qual));
 161         memcpy(&data->payloads, &req->qtcb->bottom.support.els,
 162                sizeof(req->qtcb->bottom.support.els));
 163 }
 164
 165 static long zfcp_cfdc_dev_ioctl(struct file *file, unsigned int command,
 166                                 unsigned long buffer)
 167 {
 168         struct zfcp_cfdc_data *data;
 169         struct zfcp_cfdc_data __user *data_user;
 170         struct zfcp_adapter *adapter;
 171         struct zfcp_fsf_req *req;
 172         struct zfcp_fsf_cfdc *fsf_cfdc;
 173         int retval;
 174
 175         if (command != ZFCP_CFDC_IOC)
 176                 return -ENOTTY;
 177
 178         data_user = (void __user *) buffer;
 179         if (!data_user)
 180                 return -EINVAL;
 181
 182         fsf_cfdc = kmalloc(sizeof(struct zfcp_fsf_cfdc), GFP_KERNEL);
 183         if (!fsf_cfdc)
 184                 return -ENOMEM;
 185
 186         data = kmalloc(sizeof(struct zfcp_cfdc_data), GFP_KERNEL);
 187         if (!data) {
 188                 retval = -ENOMEM;
 189                 goto no_mem_sense;
 190         }
 191
 192         retval = copy_from_user(data, data_user, sizeof(*data));
 193         if (retval) {
 194                 retval = -EFAULT;
 195                 goto free_buffer;
 196         }
 197
 198         if (data->signature != 0xCFDCACDF) {
 199                 retval = -EINVAL;
 200                 goto free_buffer;
 201         }
 202
 203         retval = zfcp_cfdc_set_fsf(fsf_cfdc, data->command);
 204
 205         adapter = zfcp_cfdc_get_adapter(data->devno);
 206         if (!adapter) {
 207                 retval = -ENXIO;
 208                 goto free_buffer;
 209         }
 210
 211         retval = zfcp_cfdc_sg_setup(data->command, fsf_cfdc->sg,
 212                                     data_user->control_file);
 213         if (retval)
 214                 goto adapter_put;
 215         req = zfcp_fsf_control_file(adapter, fsf_cfdc);
 216         if (IS_ERR(req)) {
 217                 retval = PTR_ERR(req);
 218                 goto free_sg;
 219         }
 220
 221         if (req->status & ZFCP_STATUS_FSFREQ_ERROR) {
 222                 retval = -ENXIO;
 223                 goto free_fsf;
 224         }
 225
 226         zfcp_cfdc_req_to_sense(data, req);
 227         retval = copy_to_user(data_user, data, sizeof(*data_user));
 228         if (retval) {
 229                 retval = -EFAULT;
 230                 goto free_fsf;
 231         }
 232
 233         if (data->command & ZFCP_CFDC_UPLOAD)
 234                 retval = zfcp_cfdc_copy_to_user(&data_user->control_file,
 235                                                 fsf_cfdc->sg);
 236
 237  free_fsf:
 238         zfcp_fsf_req_free(req);
 239  free_sg:
 240         zfcp_sg_free_table(fsf_cfdc->sg, ZFCP_CFDC_PAGES);
 241  adapter_put:
 242         zfcp_ccw_adapter_put(adapter);
 243  free_buffer:
 244         kfree(data);
 245  no_mem_sense:
 246         kfree(fsf_cfdc);
 247         return retval;
 248 }
 249
 250 static const struct file_operations zfcp_cfdc_fops = {
 251         .unlocked_ioctl = zfcp_cfdc_dev_ioctl,
 252 #ifdef CONFIG_COMPAT
 253         .compat_ioctl = zfcp_cfdc_dev_ioctl
 254 #endif
 255 };
 256
 257 struct miscdevice zfcp_cfdc_misc = {
 258         .minor = MISC_DYNAMIC_MINOR,
 259         .name = "zfcp_cfdc",
 260         .fops = &zfcp_cfdc_fops,
 261 };