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_device.h> 19 #include <scsi/scsi_eh.h> 20 #include <scsi/scsi_host.h> 21 #include <scsi/scsi_ioctl.h> 22 #include <scsi/scsi_request.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 && (cmd[0] != TEST_UNIT_READY)) { 114 printk(KERN_INFO "Device not ready. Make sure" 115 " there is a disc in the drive.\n"); 116 break; 117 } 118 case UNIT_ATTENTION: 119 if (sdev->removable) { 120 sdev->changed = 1; 121 result = 0; /* This is no longer considered an error */ 122 break; 123 } 124 default: /* Fall through for non-removable media */ 125 sdev_printk(KERN_INFO, sdev, 126 "ioctl_internal_command return code = %x\n", 127 result); 128 scsi_print_sense_hdr(" ", &sshdr); 129 break; 130 } 131 } 132 133 SCSI_LOG_IOCTL(2, printk("IOCTL Releasing command\n")); 134 return result; 135 } 136 137 int scsi_set_medium_removal(struct scsi_device *sdev, char state) 138 { 139 char scsi_cmd[MAX_COMMAND_SIZE]; 140 int ret; 141 142 if (!sdev->removable || !sdev->lockable) 143 return 0; 144 145 scsi_cmd[0] = ALLOW_MEDIUM_REMOVAL; 146 scsi_cmd[1] = 0; 147 scsi_cmd[2] = 0; 148 scsi_cmd[3] = 0; 149 scsi_cmd[4] = state; 150 scsi_cmd[5] = 0; 151 152 ret = ioctl_internal_command(sdev, scsi_cmd, 153 IOCTL_NORMAL_TIMEOUT, NORMAL_RETRIES); 154 if (ret == 0) 155 sdev->locked = (state == SCSI_REMOVAL_PREVENT); 156 return ret; 157 } 158 EXPORT_SYMBOL(scsi_set_medium_removal); 159 160 /* 161 * The scsi_ioctl_get_pci() function places into arg the value 162 * pci_dev::slot_name (8 characters) for the PCI device (if any). 163 * Returns: 0 on success 164 * -ENXIO if there isn't a PCI device pointer 165 * (could be because the SCSI driver hasn't been 166 * updated yet, or because it isn't a SCSI 167 * device) 168 * any copy_to_user() error on failure there 169 */ 170 static int scsi_ioctl_get_pci(struct scsi_device *sdev, void __user *arg) 171 { 172 struct device *dev = scsi_get_device(sdev->host); 173 174 if (!dev) 175 return -ENXIO; 176 return copy_to_user(arg, dev->bus_id, sizeof(dev->bus_id))? -EFAULT: 0; 177 } 178 179 180 /* 181 * the scsi_ioctl() function differs from most ioctls in that it does 182 * not take a major/minor number as the dev field. Rather, it takes 183 * a pointer to a scsi_devices[] element, a structure. 184 */ 185 int scsi_ioctl(struct scsi_device *sdev, int cmd, void __user *arg) 186 { 187 char scsi_cmd[MAX_COMMAND_SIZE]; 188 189 /* No idea how this happens.... */ 190 if (!sdev) 191 return -ENXIO; 192 193 /* 194 * If we are in the middle of error recovery, don't let anyone 195 * else try and use this device. Also, if error recovery fails, it 196 * may try and take the device offline, in which case all further 197 * access to the device is prohibited. 198 */ 199 if (!scsi_block_when_processing_errors(sdev)) 200 return -ENODEV; 201 202 /* Check for deprecated ioctls ... all the ioctls which don't 203 * follow the new unique numbering scheme are deprecated */ 204 switch (cmd) { 205 case SCSI_IOCTL_SEND_COMMAND: 206 case SCSI_IOCTL_TEST_UNIT_READY: 207 case SCSI_IOCTL_BENCHMARK_COMMAND: 208 case SCSI_IOCTL_SYNC: 209 case SCSI_IOCTL_START_UNIT: 210 case SCSI_IOCTL_STOP_UNIT: 211 printk(KERN_WARNING "program %s is using a deprecated SCSI " 212 "ioctl, please convert it to SG_IO\n", current->comm); 213 break; 214 default: 215 break; 216 } 217 218 switch (cmd) { 219 case SCSI_IOCTL_GET_IDLUN: 220 if (!access_ok(VERIFY_WRITE, arg, sizeof(struct scsi_idlun))) 221 return -EFAULT; 222 223 __put_user((sdev->id & 0xff) 224 + ((sdev->lun & 0xff) << 8) 225 + ((sdev->channel & 0xff) << 16) 226 + ((sdev->host->host_no & 0xff) << 24), 227 &((struct scsi_idlun __user *)arg)->dev_id); 228 __put_user(sdev->host->unique_id, 229 &((struct scsi_idlun __user *)arg)->host_unique_id); 230 return 0; 231 case SCSI_IOCTL_GET_BUS_NUMBER: 232 return put_user(sdev->host->host_no, (int __user *)arg); 233 case SCSI_IOCTL_PROBE_HOST: 234 return ioctl_probe(sdev->host, arg); 235 case SCSI_IOCTL_SEND_COMMAND: 236 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO)) 237 return -EACCES; 238 return sg_scsi_ioctl(NULL, sdev->request_queue, NULL, arg); 239 case SCSI_IOCTL_DOORLOCK: 240 return scsi_set_medium_removal(sdev, SCSI_REMOVAL_PREVENT); 241 case SCSI_IOCTL_DOORUNLOCK: 242 return scsi_set_medium_removal(sdev, SCSI_REMOVAL_ALLOW); 243 case SCSI_IOCTL_TEST_UNIT_READY: 244 return scsi_test_unit_ready(sdev, IOCTL_NORMAL_TIMEOUT, 245 NORMAL_RETRIES); 246 case SCSI_IOCTL_START_UNIT: 247 scsi_cmd[0] = START_STOP; 248 scsi_cmd[1] = 0; 249 scsi_cmd[2] = scsi_cmd[3] = scsi_cmd[5] = 0; 250 scsi_cmd[4] = 1; 251 return ioctl_internal_command(sdev, scsi_cmd, 252 START_STOP_TIMEOUT, NORMAL_RETRIES); 253 case SCSI_IOCTL_STOP_UNIT: 254 scsi_cmd[0] = START_STOP; 255 scsi_cmd[1] = 0; 256 scsi_cmd[2] = scsi_cmd[3] = scsi_cmd[5] = 0; 257 scsi_cmd[4] = 0; 258 return ioctl_internal_command(sdev, scsi_cmd, 259 START_STOP_TIMEOUT, NORMAL_RETRIES); 260 case SCSI_IOCTL_GET_PCI: 261 return scsi_ioctl_get_pci(sdev, arg); 262 default: 263 if (sdev->host->hostt->ioctl) 264 return sdev->host->hostt->ioctl(sdev, cmd, arg); 265 } 266 return -EINVAL; 267 } 268 EXPORT_SYMBOL(scsi_ioctl); 269 270 /* 271 * the scsi_nonblock_ioctl() function is designed for ioctls which may 272 * be executed even if the device is in recovery. 273 */ 274 int scsi_nonblockable_ioctl(struct scsi_device *sdev, int cmd, 275 void __user *arg, struct file *filp) 276 { 277 int val, result; 278 279 /* The first set of iocts may be executed even if we're doing 280 * error processing, as long as the device was opened 281 * non-blocking */ 282 if (filp && filp->f_flags & O_NONBLOCK) { 283 if (scsi_host_in_recovery(sdev->host)) 284 return -ENODEV; 285 } else if (!scsi_block_when_processing_errors(sdev)) 286 return -ENODEV; 287 288 switch (cmd) { 289 case SG_SCSI_RESET: 290 result = get_user(val, (int __user *)arg); 291 if (result) 292 return result; 293 if (val == SG_SCSI_RESET_NOTHING) 294 return 0; 295 switch (val) { 296 case SG_SCSI_RESET_DEVICE: 297 val = SCSI_TRY_RESET_DEVICE; 298 break; 299 case SG_SCSI_RESET_BUS: 300 val = SCSI_TRY_RESET_BUS; 301 break; 302 case SG_SCSI_RESET_HOST: 303 val = SCSI_TRY_RESET_HOST; 304 break; 305 default: 306 return -EINVAL; 307 } 308 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO)) 309 return -EACCES; 310 return (scsi_reset_provider(sdev, val) == 311 SUCCESS) ? 0 : -EIO; 312 } 313 return -ENODEV; 314 } 315 EXPORT_SYMBOL(scsi_nonblockable_ioctl); 316