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/slab.h>
  14 #include <linux/types.h>
  15 #include <linux/miscdevice.h>
  16 #include <asm/compat.h>
  17 #include <asm/ccwdev.h>
  18 #include "zfcp_def.h"
  19 #include "zfcp_ext.h"
  20 #include "zfcp_fsf.h"
  21
  22 #define ZFCP_CFDC_CMND_DOWNLOAD_NORMAL          0x00010001
  23 #define ZFCP_CFDC_CMND_DOWNLOAD_FORCE           0x00010101
  24 #define ZFCP_CFDC_CMND_FULL_ACCESS              0x00000201
  25 #define ZFCP_CFDC_CMND_RESTRICTED_ACCESS        0x00000401
  26 #define ZFCP_CFDC_CMND_UPLOAD                   0x00010002
  27
  28 #define ZFCP_CFDC_DOWNLOAD                      0x00000001
  29 #define ZFCP_CFDC_UPLOAD                        0x00000002
  30 #define ZFCP_CFDC_WITH_CONTROL_FILE             0x00010000
  31
  32 #define ZFCP_CFDC_IOC_MAGIC                     0xDD
  33 #define ZFCP_CFDC_IOC \
  34         _IOWR(ZFCP_CFDC_IOC_MAGIC, 0, struct zfcp_cfdc_data)
  35
  36 /**
  37  * struct zfcp_cfdc_data - data for ioctl cfdc interface
  38  * @signature: request signature
  39  * @devno: FCP adapter device number
  40  * @command: command code
  41  * @fsf_status: returns status of FSF command to userspace
  42  * @fsf_status_qual: returned to userspace
  43  * @payloads: access conflicts list
  44  * @control_file: access control table
  45  */
  46 struct zfcp_cfdc_data {
  47         u32 signature;
  48         u32 devno;
  49         u32 command;
  50         u32 fsf_status;
  51         u8  fsf_status_qual[FSF_STATUS_QUALIFIER_SIZE];
  52         u8  payloads[256];
  53         u8  control_file[0];
  54 };
  55
  56 static int zfcp_cfdc_copy_from_user(struct scatterlist *sg,
  57                                     void __user *user_buffer)
  58 {
  59         unsigned int length;
  60         unsigned int size = ZFCP_CFDC_MAX_SIZE;
  61
  62         while (size) {
  63                 length = min((unsigned int)size, sg->length);
  64                 if (copy_from_user(sg_virt(sg++), user_buffer, length))
  65                         return -EFAULT;
  66                 user_buffer += length;
  67                 size -= length;
  68         }
  69         return 0;
  70 }
  71
  72 static int zfcp_cfdc_copy_to_user(void __user  *user_buffer,
  73                                   struct scatterlist *sg)
  74 {
  75         unsigned int length;
  76         unsigned int size = ZFCP_CFDC_MAX_SIZE;
  77
  78         while (size) {
  79                 length = min((unsigned int) size, sg->length);
  80                 if (copy_to_user(user_buffer, sg_virt(sg++), length))
  81                         return -EFAULT;
  82                 user_buffer += length;
  83                 size -= length;
  84         }
  85         return 0;
  86 }
  87
  88 static struct zfcp_adapter *zfcp_cfdc_get_adapter(u32 devno)
  89 {
  90         char busid[9];
  91         struct ccw_device *cdev;
  92         struct zfcp_adapter *adapter;
  93
  94         snprintf(busid, sizeof(busid), "0.0.%04x", devno);
  95         cdev = get_ccwdev_by_busid(&zfcp_ccw_driver, busid);
  96         if (!cdev)
  97                 return NULL;
  98
  99         adapter = zfcp_ccw_adapter_by_cdev(cdev);
 100
 101         put_device(&cdev->dev);
 102         return adapter;
 103 }
 104
 105 static int zfcp_cfdc_set_fsf(struct zfcp_fsf_cfdc *fsf_cfdc, int command)
 106 {
 107         switch (command) {
 108         case ZFCP_CFDC_CMND_DOWNLOAD_NORMAL:
 109                 fsf_cfdc->command = FSF_QTCB_DOWNLOAD_CONTROL_FILE;
 110                 fsf_cfdc->option = FSF_CFDC_OPTION_NORMAL_MODE;
 111                 break;
 112         case ZFCP_CFDC_CMND_DOWNLOAD_FORCE:
 113                 fsf_cfdc->command = FSF_QTCB_DOWNLOAD_CONTROL_FILE;
 114                 fsf_cfdc->option = FSF_CFDC_OPTION_FORCE;
 115                 break;
 116         case ZFCP_CFDC_CMND_FULL_ACCESS:
 117                 fsf_cfdc->command = FSF_QTCB_DOWNLOAD_CONTROL_FILE;
 118                 fsf_cfdc->option = FSF_CFDC_OPTION_FULL_ACCESS;
 119                 break;
 120         case ZFCP_CFDC_CMND_RESTRICTED_ACCESS:
 121                 fsf_cfdc->command = FSF_QTCB_DOWNLOAD_CONTROL_FILE;
 122                 fsf_cfdc->option = FSF_CFDC_OPTION_RESTRICTED_ACCESS;
 123                 break;
 124         case ZFCP_CFDC_CMND_UPLOAD:
 125                 fsf_cfdc->command = FSF_QTCB_UPLOAD_CONTROL_FILE;
 126                 fsf_cfdc->option = 0;
 127                 break;
 128         default:
 129                 return -EINVAL;
 130         }
 131
 132         return 0;
 133 }
 134
 135 static int zfcp_cfdc_sg_setup(int command, struct scatterlist *sg,
 136                               u8 __user *control_file)
 137 {
 138         int retval;
 139         retval = zfcp_sg_setup_table(sg, ZFCP_CFDC_PAGES);
 140         if (retval)
 141                 return retval;
 142
 143         sg[ZFCP_CFDC_PAGES - 1].length = ZFCP_CFDC_MAX_SIZE % PAGE_SIZE;
 144
 145         if (command & ZFCP_CFDC_WITH_CONTROL_FILE &&
 146             command & ZFCP_CFDC_DOWNLOAD) {
 147                 retval = zfcp_cfdc_copy_from_user(sg, control_file);
 148                 if (retval) {
 149                         zfcp_sg_free_table(sg, ZFCP_CFDC_PAGES);
 150                         return -EFAULT;
 151                 }
 152         }
 153
 154         return 0;
 155 }
 156
 157 static void zfcp_cfdc_req_to_sense(struct zfcp_cfdc_data *data,
 158                                    struct zfcp_fsf_req *req)
 159 {
 160         data->fsf_status = req->qtcb->header.fsf_status;
 161         memcpy(&data->fsf_status_qual, &req->qtcb->header.fsf_status_qual,
 162                sizeof(union fsf_status_qual));
 163         memcpy(&data->payloads, &req->qtcb->bottom.support.els,
 164                sizeof(req->qtcb->bottom.support.els));
 165 }
 166
 167 static long zfcp_cfdc_dev_ioctl(struct file *file, unsigned int command,
 168                                 unsigned long arg)
 169 {
 170         struct zfcp_cfdc_data *data;
 171         struct zfcp_cfdc_data __user *data_user;
 172         struct zfcp_adapter *adapter;
 173         struct zfcp_fsf_req *req;
 174         struct zfcp_fsf_cfdc *fsf_cfdc;
 175         int retval;
 176
 177         if (command != ZFCP_CFDC_IOC)
 178                 return -ENOTTY;
 179
 180         if (is_compat_task())
 181                 data_user = compat_ptr(arg);
 182         else
 183                 data_user = (void __user *)arg;
 184
 185         if (!data_user)
 186                 return -EINVAL;
 187
 188         fsf_cfdc = kmalloc(sizeof(struct zfcp_fsf_cfdc), GFP_KERNEL);
 189         if (!fsf_cfdc)
 190                 return -ENOMEM;
 191
 192         data = kmalloc(sizeof(struct zfcp_cfdc_data), GFP_KERNEL);
 193         if (!data) {
 194                 retval = -ENOMEM;
 195                 goto no_mem_sense;
 196         }
 197
 198         retval = copy_from_user(data, data_user, sizeof(*data));
 199         if (retval) {
 200                 retval = -EFAULT;
 201                 goto free_buffer;
 202         }
 203
 204         if (data->signature != 0xCFDCACDF) {
 205                 retval = -EINVAL;
 206                 goto free_buffer;
 207         }
 208
 209         retval = zfcp_cfdc_set_fsf(fsf_cfdc, data->command);
 210
 211         adapter = zfcp_cfdc_get_adapter(data->devno);
 212         if (!adapter) {
 213                 retval = -ENXIO;
 214                 goto free_buffer;
 215         }
 216
 217         retval = zfcp_cfdc_sg_setup(data->command, fsf_cfdc->sg,
 218                                     data_user->control_file);
 219         if (retval)
 220                 goto adapter_put;
 221         req = zfcp_fsf_control_file(adapter, fsf_cfdc);
 222         if (IS_ERR(req)) {
 223                 retval = PTR_ERR(req);
 224                 goto free_sg;
 225         }
 226
 227         if (req->status & ZFCP_STATUS_FSFREQ_ERROR) {
 228                 retval = -ENXIO;
 229                 goto free_fsf;
 230         }
 231
 232         zfcp_cfdc_req_to_sense(data, req);
 233         retval = copy_to_user(data_user, data, sizeof(*data_user));
 234         if (retval) {
 235                 retval = -EFAULT;
 236                 goto free_fsf;
 237         }
 238
 239         if (data->command & ZFCP_CFDC_UPLOAD)
 240                 retval = zfcp_cfdc_copy_to_user(&data_user->control_file,
 241                                                 fsf_cfdc->sg);
 242
 243  free_fsf:
 244         zfcp_fsf_req_free(req);
 245  free_sg:
 246         zfcp_sg_free_table(fsf_cfdc->sg, ZFCP_CFDC_PAGES);
 247  adapter_put:
 248         zfcp_ccw_adapter_put(adapter);
 249  free_buffer:
 250         kfree(data);
 251  no_mem_sense:
 252         kfree(fsf_cfdc);
 253         return retval;
 254 }
 255
 256 static const struct file_operations zfcp_cfdc_fops = {
 257         .open = nonseekable_open,
 258         .unlocked_ioctl = zfcp_cfdc_dev_ioctl,
 259 #ifdef CONFIG_COMPAT
 260         .compat_ioctl = zfcp_cfdc_dev_ioctl
 261 #endif
 262 };
 263
 264 struct miscdevice zfcp_cfdc_misc = {
 265         .minor = MISC_DYNAMIC_MINOR,
 266         .name = "zfcp_cfdc",
 267         .fops = &zfcp_cfdc_fops,
 268 };