1 /* 2 * Changes: 3 * Arnaldo Carvalho de Melo <acme@conectiva.com.br> 08/23/2000 4 * - get rid of some verify_areas and use __copy*user and __get/put_user 5 * for the ones that remain 6 */ 7 #include <linux/module.h> 8 #include <linux/blkdev.h> 9 #include <linux/interrupt.h> 10 #include <linux/errno.h> 11 #include <linux/kernel.h> 12 #include <linux/sched.h> 13 #include <linux/mm.h> 14 #include <linux/string.h> 15 #include <asm/uaccess.h> 16 17 #include <scsi/scsi.h> 18 #include <scsi/scsi_cmnd.h> 19 #include <scsi/scsi_device.h> 20 #include <scsi/scsi_eh.h> 21 #include <scsi/scsi_host.h> 22 #include <scsi/scsi_ioctl.h> 23 #include <scsi/sg.h> 24 #include <scsi/scsi_dbg.h> 25 26 #include "scsi_logging.h" 27 28 #define NORMAL_RETRIES 5 29 #define IOCTL_NORMAL_TIMEOUT (10 * HZ) 30 31 #define MAX_BUF PAGE_SIZE 32 33 /** 34 * ioctl_probe -- return host identification 35 * @host: host to identify 36 * @buffer: userspace buffer for identification 37 * 38 * Return an identifying string at @buffer, if @buffer is non-NULL, filling 39 * to the length stored at * (int *) @buffer. 40 */ 41 static int ioctl_probe(struct Scsi_Host *host, void __user *buffer) 42 { 43 unsigned int len, slen; 44 const char *string; 45 46 if (buffer) { 47 if (get_user(len, (unsigned int __user *) buffer)) 48 return -EFAULT; 49 50 if (host->hostt->info) 51 string = host->hostt->info(host); 52 else 53 string = host->hostt->name; 54 if (string) { 55 slen = strlen(string); 56 if (len > slen) 57 len = slen + 1; 58 if (copy_to_user(buffer, string, len)) 59 return -EFAULT; 60 } 61 } 62 return 1; 63 } 64 65 /* 66 67 * The SCSI_IOCTL_SEND_COMMAND ioctl sends a command out to the SCSI host. 68 * The IOCTL_NORMAL_TIMEOUT and NORMAL_RETRIES variables are used. 69 * 70 * dev is the SCSI device struct ptr, *(int *) arg is the length of the 71 * input data, if any, not including the command string & counts, 72 * *((int *)arg + 1) is the output buffer size in bytes. 73 * 74 * *(char *) ((int *) arg)[2] the actual command byte. 75 * 76 * Note that if more than MAX_BUF bytes are requested to be transferred, 77 * the ioctl will fail with error EINVAL. 78 * 79 * This size *does not* include the initial lengths that were passed. 80 * 81 * The SCSI command is read from the memory location immediately after the 82 * length words, and the input data is right after the command. The SCSI 83 * routines know the command size based on the opcode decode. 84 * 85 * The output area is then filled in starting from the command byte. 86 */ 87 88 static int ioctl_internal_command(struct scsi_device *sdev, char *cmd, 89 int timeout, int retries) 90 { 91 int result; 92 struct scsi_sense_hdr sshdr; 93 94 SCSI_LOG_IOCTL(1, printk("Trying ioctl with scsi command %d\n", *cmd)); 95 96 result = scsi_execute_req(sdev, cmd, DMA_NONE, NULL, 0, 97 &sshdr, timeout, retries); 98 99 SCSI_LOG_IOCTL(2, printk("Ioctl returned 0x%x\n", result)); 100 101 if ((driver_byte(result) & DRIVER_SENSE) && 102 (scsi_sense_valid(&sshdr))) { 103 switch (sshdr.sense_key) { 104 case ILLEGAL_REQUEST: 105 if (cmd[0] == ALLOW_MEDIUM_REMOVAL) 106 sdev->lockable = 0; 107 else 108 printk(KERN_INFO "ioctl_internal_command: " 109 "ILLEGAL REQUEST asc=0x%x ascq=0x%x\n", 110 sshdr.asc, sshdr.ascq); 111 break; 112 case NOT_READY: /* This happens if there is no disc in drive */ 113 if (sdev->removable) 114 break; 115 case UNIT_ATTENTION: 116 if (sdev->removable) { 117 sdev->changed = 1; 118 result = 0; /* This is no longer considered an error */ 119 break; 120 } 121 default: /* Fall through for non-removable media */ 122 sdev_printk(KERN_INFO, sdev, 123 "ioctl_internal_command return code = %x\n", 124 result); 125 scsi_print_sense_hdr(" ", &sshdr); 126 break; 127 } 128 } 129 130 SCSI_LOG_IOCTL(2, printk("IOCTL Releasing command\n")); 131 return result; 132 } 133 134 int scsi_set_medium_removal(struct scsi_device *sdev, char state) 135 { 136 char scsi_cmd[MAX_COMMAND_SIZE]; 137 int ret; 138 139 if (!sdev->removable || !sdev->lockable) 140 return 0; 141 142 scsi_cmd[0] = ALLOW_MEDIUM_REMOVAL; 143 scsi_cmd[1] = 0; 144 scsi_cmd[2] = 0; 145 scsi_cmd[3] = 0; 146 scsi_cmd[4] = state; 147 scsi_cmd[5] = 0; 148 149 ret = ioctl_internal_command(sdev, scsi_cmd, 150 IOCTL_NORMAL_TIMEOUT, NORMAL_RETRIES); 151 if (ret == 0) 152 sdev->locked = (state == SCSI_REMOVAL_PREVENT); 153 return ret; 154 } 155 EXPORT_SYMBOL(scsi_set_medium_removal); 156 157 /* 158 * The scsi_ioctl_get_pci() function places into arg the value 159 * pci_dev::slot_name (8 characters) for the PCI device (if any). 160 * Returns: 0 on success 161 * -ENXIO if there isn't a PCI device pointer 162 * (could be because the SCSI driver hasn't been 163 * updated yet, or because it isn't a SCSI 164 * device) 165 * any copy_to_user() error on failure there 166 */ 167 static int scsi_ioctl_get_pci(struct scsi_device *sdev, void __user *arg) 168 { 169 struct device *dev = scsi_get_device(sdev->host); 170 171 if (!dev) 172 return -ENXIO; 173 return copy_to_user(arg, dev->bus_id, sizeof(dev->bus_id))? -EFAULT: 0; 174 } 175 176 177 /** 178 * scsi_ioctl - Dispatch ioctl to scsi device 179 * @sdev: scsi device receiving ioctl 180 * @cmd: which ioctl is it 181 * @arg: data associated with ioctl 182 * 183 * Description: The scsi_ioctl() function differs from most ioctls in that it 184 * does not take a major/minor number as the dev field. Rather, it takes 185 * a pointer to a &struct scsi_device. 186 */ 187 int scsi_ioctl(struct scsi_device *sdev, int cmd, void __user *arg) 188 { 189 char scsi_cmd[MAX_COMMAND_SIZE]; 190 191 /* No idea how this happens.... */ 192 if (!sdev) 193 return -ENXIO; 194 195 /* 196 * If we are in the middle of error recovery, don't let anyone 197 * else try and use this device. Also, if error recovery fails, it 198 * may try and take the device offline, in which case all further 199 * access to the device is prohibited. 200 */ 201 if (!scsi_block_when_processing_errors(sdev)) 202 return -ENODEV; 203 204 /* Check for deprecated ioctls ... all the ioctls which don't 205 * follow the new unique numbering scheme are deprecated */ 206 switch (cmd) { 207 case SCSI_IOCTL_SEND_COMMAND: 208 case SCSI_IOCTL_TEST_UNIT_READY: 209 case SCSI_IOCTL_BENCHMARK_COMMAND: 210 case SCSI_IOCTL_SYNC: 211 case SCSI_IOCTL_START_UNIT: 212 case SCSI_IOCTL_STOP_UNIT: 213 printk(KERN_WARNING "program %s is using a deprecated SCSI " 214 "ioctl, please convert it to SG_IO\n", current->comm); 215 break; 216 default: 217 break; 218 } 219 220 switch (cmd) { 221 case SCSI_IOCTL_GET_IDLUN: 222 if (!access_ok(VERIFY_WRITE, arg, sizeof(struct scsi_idlun))) 223 return -EFAULT; 224 225 __put_user((sdev->id & 0xff) 226 + ((sdev->lun & 0xff) << 8) 227 + ((sdev->channel & 0xff) << 16) 228 + ((sdev->host->host_no & 0xff) << 24), 229 &((struct scsi_idlun __user *)arg)->dev_id); 230 __put_user(sdev->host->unique_id, 231 &((struct scsi_idlun __user *)arg)->host_unique_id); 232 return 0; 233 case SCSI_IOCTL_GET_BUS_NUMBER: 234 return put_user(sdev->host->host_no, (int __user *)arg); 235 case SCSI_IOCTL_PROBE_HOST: 236 return ioctl_probe(sdev->host, arg); 237 case SCSI_IOCTL_SEND_COMMAND: 238 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO)) 239 return -EACCES; 240 return sg_scsi_ioctl(NULL, sdev->request_queue, NULL, arg); 241 case SCSI_IOCTL_DOORLOCK: 242 return scsi_set_medium_removal(sdev, SCSI_REMOVAL_PREVENT); 243 case SCSI_IOCTL_DOORUNLOCK: 244 return scsi_set_medium_removal(sdev, SCSI_REMOVAL_ALLOW); 245 case SCSI_IOCTL_TEST_UNIT_READY: 246 return scsi_test_unit_ready(sdev, IOCTL_NORMAL_TIMEOUT, 247 NORMAL_RETRIES, NULL); 248 case SCSI_IOCTL_START_UNIT: 249 scsi_cmd[0] = START_STOP; 250 scsi_cmd[1] = 0; 251 scsi_cmd[2] = scsi_cmd[3] = scsi_cmd[5] = 0; 252 scsi_cmd[4] = 1; 253 return ioctl_internal_command(sdev, scsi_cmd, 254 START_STOP_TIMEOUT, NORMAL_RETRIES); 255 case SCSI_IOCTL_STOP_UNIT: 256 scsi_cmd[0] = START_STOP; 257 scsi_cmd[1] = 0; 258 scsi_cmd[2] = scsi_cmd[3] = scsi_cmd[5] = 0; 259 scsi_cmd[4] = 0; 260 return ioctl_internal_command(sdev, scsi_cmd, 261 START_STOP_TIMEOUT, NORMAL_RETRIES); 262 case SCSI_IOCTL_GET_PCI: 263 return scsi_ioctl_get_pci(sdev, arg); 264 default: 265 if (sdev->host->hostt->ioctl) 266 return sdev->host->hostt->ioctl(sdev, cmd, arg); 267 } 268 return -EINVAL; 269 } 270 EXPORT_SYMBOL(scsi_ioctl); 271 272 /** 273 * scsi_nonblock_ioctl() - Handle SG_SCSI_RESET 274 * @sdev: scsi device receiving ioctl 275 * @cmd: Must be SC_SCSI_RESET 276 * @arg: pointer to int containing SG_SCSI_RESET_{DEVICE,BUS,HOST} 277 * @filp: either NULL or a &struct file which must have the O_NONBLOCK flag. 278 */ 279 int scsi_nonblockable_ioctl(struct scsi_device *sdev, int cmd, 280 void __user *arg, struct file *filp) 281 { 282 int val, result; 283 284 /* The first set of iocts may be executed even if we're doing 285 * error processing, as long as the device was opened 286 * non-blocking */ 287 if (filp && (filp->f_flags & O_NONBLOCK)) { 288 if (scsi_host_in_recovery(sdev->host)) 289 return -ENODEV; 290 } else if (!scsi_block_when_processing_errors(sdev)) 291 return -ENODEV; 292 293 switch (cmd) { 294 case SG_SCSI_RESET: 295 result = get_user(val, (int __user *)arg); 296 if (result) 297 return result; 298 if (val == SG_SCSI_RESET_NOTHING) 299 return 0; 300 switch (val) { 301 case SG_SCSI_RESET_DEVICE: 302 val = SCSI_TRY_RESET_DEVICE; 303 break; 304 case SG_SCSI_RESET_BUS: 305 val = SCSI_TRY_RESET_BUS; 306 break; 307 case SG_SCSI_RESET_HOST: 308 val = SCSI_TRY_RESET_HOST; 309 break; 310 default: 311 return -EINVAL; 312 } 313 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO)) 314 return -EACCES; 315 return (scsi_reset_provider(sdev, val) == 316 SUCCESS) ? 0 : -EIO; 317 } 318 return -ENODEV; 319 } 320 EXPORT_SYMBOL(scsi_nonblockable_ioctl); 321