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 */ 41static 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 88static 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, NULL); 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 134int 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} 155EXPORT_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 */ 167static int scsi_ioctl_get_pci(struct scsi_device *sdev, void __user *arg) 168{ 169 struct device *dev = scsi_get_device(sdev->host); 170 const char *name; 171 172 if (!dev) 173 return -ENXIO; 174 175 name = dev_name(dev); 176 177 /* compatibility with old ioctl which only returned 178 * 20 characters */ 179 return copy_to_user(arg, name, min(strlen(name), (size_t)20)) 180 ? -EFAULT: 0; 181} 182 183 184/** 185 * scsi_ioctl - Dispatch ioctl to scsi device 186 * @sdev: scsi device receiving ioctl 187 * @cmd: which ioctl is it 188 * @arg: data associated with ioctl 189 * 190 * Description: The scsi_ioctl() function differs from most ioctls in that it 191 * does not take a major/minor number as the dev field. Rather, it takes 192 * a pointer to a &struct scsi_device. 193 */ 194int scsi_ioctl(struct scsi_device *sdev, int cmd, void __user *arg) 195{ 196 char scsi_cmd[MAX_COMMAND_SIZE]; 197 198 /* No idea how this happens.... */ 199 if (!sdev) 200 return -ENXIO; 201 202 /* 203 * If we are in the middle of error recovery, don't let anyone 204 * else try and use this device. Also, if error recovery fails, it 205 * may try and take the device offline, in which case all further 206 * access to the device is prohibited. 207 */ 208 if (!scsi_block_when_processing_errors(sdev)) 209 return -ENODEV; 210 211 /* Check for deprecated ioctls ... all the ioctls which don't 212 * follow the new unique numbering scheme are deprecated */ 213 switch (cmd) { 214 case SCSI_IOCTL_SEND_COMMAND: 215 case SCSI_IOCTL_TEST_UNIT_READY: 216 case SCSI_IOCTL_BENCHMARK_COMMAND: 217 case SCSI_IOCTL_SYNC: 218 case SCSI_IOCTL_START_UNIT: 219 case SCSI_IOCTL_STOP_UNIT: 220 printk(KERN_WARNING "program %s is using a deprecated SCSI " 221 "ioctl, please convert it to SG_IO\n", current->comm); 222 break; 223 default: 224 break; 225 } 226 227 switch (cmd) { 228 case SCSI_IOCTL_GET_IDLUN: 229 if (!access_ok(VERIFY_WRITE, arg, sizeof(struct scsi_idlun))) 230 return -EFAULT; 231 232 __put_user((sdev->id & 0xff) 233 + ((sdev->lun & 0xff) << 8) 234 + ((sdev->channel & 0xff) << 16) 235 + ((sdev->host->host_no & 0xff) << 24), 236 &((struct scsi_idlun __user *)arg)->dev_id); 237 __put_user(sdev->host->unique_id, 238 &((struct scsi_idlun __user *)arg)->host_unique_id); 239 return 0; 240 case SCSI_IOCTL_GET_BUS_NUMBER: 241 return put_user(sdev->host->host_no, (int __user *)arg); 242 case SCSI_IOCTL_PROBE_HOST: 243 return ioctl_probe(sdev->host, arg); 244 case SCSI_IOCTL_SEND_COMMAND: 245 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO)) 246 return -EACCES; 247 return sg_scsi_ioctl(sdev->request_queue, NULL, 0, arg); 248 case SCSI_IOCTL_DOORLOCK: 249 return scsi_set_medium_removal(sdev, SCSI_REMOVAL_PREVENT); 250 case SCSI_IOCTL_DOORUNLOCK: 251 return scsi_set_medium_removal(sdev, SCSI_REMOVAL_ALLOW); 252 case SCSI_IOCTL_TEST_UNIT_READY: 253 return scsi_test_unit_ready(sdev, IOCTL_NORMAL_TIMEOUT, 254 NORMAL_RETRIES, NULL); 255 case SCSI_IOCTL_START_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] = 1; 260 return ioctl_internal_command(sdev, scsi_cmd, 261 START_STOP_TIMEOUT, NORMAL_RETRIES); 262 case SCSI_IOCTL_STOP_UNIT: 263 scsi_cmd[0] = START_STOP; 264 scsi_cmd[1] = 0; 265 scsi_cmd[2] = scsi_cmd[3] = scsi_cmd[5] = 0; 266 scsi_cmd[4] = 0; 267 return ioctl_internal_command(sdev, scsi_cmd, 268 START_STOP_TIMEOUT, NORMAL_RETRIES); 269 case SCSI_IOCTL_GET_PCI: 270 return scsi_ioctl_get_pci(sdev, arg); 271 default: 272 if (sdev->host->hostt->ioctl) 273 return sdev->host->hostt->ioctl(sdev, cmd, arg); 274 } 275 return -EINVAL; 276} 277EXPORT_SYMBOL(scsi_ioctl); 278 279/** 280 * scsi_nonblockable_ioctl() - Handle SG_SCSI_RESET 281 * @sdev: scsi device receiving ioctl 282 * @cmd: Must be SC_SCSI_RESET 283 * @arg: pointer to int containing SG_SCSI_RESET_{DEVICE,BUS,HOST} 284 * @ndelay: file mode O_NDELAY flag 285 */ 286int scsi_nonblockable_ioctl(struct scsi_device *sdev, int cmd, 287 void __user *arg, int ndelay) 288{ 289 int val, result; 290 291 /* The first set of iocts may be executed even if we're doing 292 * error processing, as long as the device was opened 293 * non-blocking */ 294 if (ndelay) { 295 if (scsi_host_in_recovery(sdev->host)) 296 return -ENODEV; 297 } else if (!scsi_block_when_processing_errors(sdev)) 298 return -ENODEV; 299 300 switch (cmd) { 301 case SG_SCSI_RESET: 302 result = get_user(val, (int __user *)arg); 303 if (result) 304 return result; 305 if (val == SG_SCSI_RESET_NOTHING) 306 return 0; 307 switch (val) { 308 case SG_SCSI_RESET_DEVICE: 309 val = SCSI_TRY_RESET_DEVICE; 310 break; 311 case SG_SCSI_RESET_TARGET: 312 val = SCSI_TRY_RESET_TARGET; 313 break; 314 case SG_SCSI_RESET_BUS: 315 val = SCSI_TRY_RESET_BUS; 316 break; 317 case SG_SCSI_RESET_HOST: 318 val = SCSI_TRY_RESET_HOST; 319 break; 320 default: 321 return -EINVAL; 322 } 323 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO)) 324 return -EACCES; 325 return (scsi_reset_provider(sdev, val) == 326 SUCCESS) ? 0 : -EIO; 327 } 328 return -ENODEV; 329} 330EXPORT_SYMBOL(scsi_nonblockable_ioctl); 331