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 *ccwdev;
  90         struct zfcp_adapter *adapter = NULL;
  91
  92         snprintf(busid, sizeof(busid), "0.0.%04x", devno);
  93         ccwdev = get_ccwdev_by_busid(&zfcp_ccw_driver, busid);
  94         if (!ccwdev)
  95                 goto out;
  96
  97         adapter = dev_get_drvdata(&ccwdev->dev);
  98         if (!adapter)
  99                 goto out_put;
 100
 101         zfcp_adapter_get(adapter);
 102 out_put:
 103         put_device(&ccwdev->dev);
 104 out:
 105         return adapter;
 106 }
 107
 108 static int zfcp_cfdc_set_fsf(struct zfcp_fsf_cfdc *fsf_cfdc, int command)
 109 {
 110         switch (command) {
 111         case ZFCP_CFDC_CMND_DOWNLOAD_NORMAL:
 112                 fsf_cfdc->command = FSF_QTCB_DOWNLOAD_CONTROL_FILE;
 113                 fsf_cfdc->option = FSF_CFDC_OPTION_NORMAL_MODE;
 114                 break;
 115         case ZFCP_CFDC_CMND_DOWNLOAD_FORCE:
 116                 fsf_cfdc->command = FSF_QTCB_DOWNLOAD_CONTROL_FILE;
 117                 fsf_cfdc->option = FSF_CFDC_OPTION_FORCE;
 118                 break;
 119         case ZFCP_CFDC_CMND_FULL_ACCESS:
 120                 fsf_cfdc->command = FSF_QTCB_DOWNLOAD_CONTROL_FILE;
 121                 fsf_cfdc->option = FSF_CFDC_OPTION_FULL_ACCESS;
 122                 break;
 123         case ZFCP_CFDC_CMND_RESTRICTED_ACCESS:
 124                 fsf_cfdc->command = FSF_QTCB_DOWNLOAD_CONTROL_FILE;
 125                 fsf_cfdc->option = FSF_CFDC_OPTION_RESTRICTED_ACCESS;
 126                 break;
 127         case ZFCP_CFDC_CMND_UPLOAD:
 128                 fsf_cfdc->command = FSF_QTCB_UPLOAD_CONTROL_FILE;
 129                 fsf_cfdc->option = 0;
 130                 break;
 131         default:
 132                 return -EINVAL;
 133         }
 134
 135         return 0;
 136 }
 137
 138 static int zfcp_cfdc_sg_setup(int command, struct scatterlist *sg,
 139                               u8 __user *control_file)
 140 {
 141         int retval;
 142         retval = zfcp_sg_setup_table(sg, ZFCP_CFDC_PAGES);
 143         if (retval)
 144                 return retval;
 145
 146         sg[ZFCP_CFDC_PAGES - 1].length = ZFCP_CFDC_MAX_SIZE % PAGE_SIZE;
 147
 148         if (command & ZFCP_CFDC_WITH_CONTROL_FILE &&
 149             command & ZFCP_CFDC_DOWNLOAD) {
 150                 retval = zfcp_cfdc_copy_from_user(sg, control_file);
 151                 if (retval) {
 152                         zfcp_sg_free_table(sg, ZFCP_CFDC_PAGES);
 153                         return -EFAULT;
 154                 }
 155         }
 156
 157         return 0;
 158 }
 159
 160 static void zfcp_cfdc_req_to_sense(struct zfcp_cfdc_data *data,
 161                                    struct zfcp_fsf_req *req)
 162 {
 163         data->fsf_status = req->qtcb->header.fsf_status;
 164         memcpy(&data->fsf_status_qual, &req->qtcb->header.fsf_status_qual,
 165                sizeof(union fsf_status_qual));
 166         memcpy(&data->payloads, &req->qtcb->bottom.support.els,
 167                sizeof(req->qtcb->bottom.support.els));
 168 }
 169
 170 static long zfcp_cfdc_dev_ioctl(struct file *file, unsigned int command,
 171                                 unsigned long buffer)
 172 {
 173         struct zfcp_cfdc_data *data;
 174         struct zfcp_cfdc_data __user *data_user;
 175         struct zfcp_adapter *adapter;
 176         struct zfcp_fsf_req *req;
 177         struct zfcp_fsf_cfdc *fsf_cfdc;
 178         int retval;
 179
 180         if (command != ZFCP_CFDC_IOC)
 181                 return -ENOTTY;
 182
 183         data_user = (void __user *) buffer;
 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         zfcp_adapter_get(adapter);
 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_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         .unlocked_ioctl = zfcp_cfdc_dev_ioctl,
 258 #ifdef CONFIG_COMPAT
 259         .compat_ioctl = zfcp_cfdc_dev_ioctl
 260 #endif
 261 };
 262
 263 struct miscdevice zfcp_cfdc_misc = {
 264         .minor = MISC_DYNAMIC_MINOR,
 265         .name = "zfcp_cfdc",
 266         .fops = &zfcp_cfdc_fops,
 267 };