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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /drivers/scsi/scsi_ioctl.c
Initial import
Diffstat (limited to 'drivers/scsi/scsi_ioctl.c')
-rw-r--r--drivers/scsi/scsi_ioctl.c289
1 files changed, 289 insertions, 0 deletions
diff --git a/drivers/scsi/scsi_ioctl.c b/drivers/scsi/scsi_ioctl.c
new file mode 100644
index 000000000..c4f7b56fa
--- /dev/null
+++ b/drivers/scsi/scsi_ioctl.c
@@ -0,0 +1,289 @@
+/*
+ * Changes:
+ * Arnaldo Carvalho de Melo <acme@conectiva.com.br> 08/23/2000
+ * - get rid of some verify_areas and use __copy*user and __get/put_user
+ * for the ones that remain
+ */
+#include <linux/module.h>
+#include <linux/blkdev.h>
+#include <linux/interrupt.h>
+#include <linux/errno.h>
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/mm.h>
+#include <linux/string.h>
+#include <asm/uaccess.h>
+
+#include <scsi/scsi.h>
+#include <scsi/scsi_cmnd.h>
+#include <scsi/scsi_device.h>
+#include <scsi/scsi_eh.h>
+#include <scsi/scsi_host.h>
+#include <scsi/scsi_ioctl.h>
+#include <scsi/sg.h>
+#include <scsi/scsi_dbg.h>
+
+#include "scsi_logging.h"
+
+#define NORMAL_RETRIES 5
+#define IOCTL_NORMAL_TIMEOUT (10 * HZ)
+
+#define MAX_BUF PAGE_SIZE
+
+/**
+ * ioctl_probe -- return host identification
+ * @host: host to identify
+ * @buffer: userspace buffer for identification
+ *
+ * Return an identifying string at @buffer, if @buffer is non-NULL, filling
+ * to the length stored at * (int *) @buffer.
+ */
+static int ioctl_probe(struct Scsi_Host *host, void __user *buffer)
+{
+ unsigned int len, slen;
+ const char *string;
+
+ if (buffer) {
+ if (get_user(len, (unsigned int __user *) buffer))
+ return -EFAULT;
+
+ if (host->hostt->info)
+ string = host->hostt->info(host);
+ else
+ string = host->hostt->name;
+ if (string) {
+ slen = strlen(string);
+ if (len > slen)
+ len = slen + 1;
+ if (copy_to_user(buffer, string, len))
+ return -EFAULT;
+ }
+ }
+ return 1;
+}
+
+/*
+
+ * The SCSI_IOCTL_SEND_COMMAND ioctl sends a command out to the SCSI host.
+ * The IOCTL_NORMAL_TIMEOUT and NORMAL_RETRIES variables are used.
+ *
+ * dev is the SCSI device struct ptr, *(int *) arg is the length of the
+ * input data, if any, not including the command string & counts,
+ * *((int *)arg + 1) is the output buffer size in bytes.
+ *
+ * *(char *) ((int *) arg)[2] the actual command byte.
+ *
+ * Note that if more than MAX_BUF bytes are requested to be transferred,
+ * the ioctl will fail with error EINVAL.
+ *
+ * This size *does not* include the initial lengths that were passed.
+ *
+ * The SCSI command is read from the memory location immediately after the
+ * length words, and the input data is right after the command. The SCSI
+ * routines know the command size based on the opcode decode.
+ *
+ * The output area is then filled in starting from the command byte.
+ */
+
+static int ioctl_internal_command(struct scsi_device *sdev, char *cmd,
+ int timeout, int retries)
+{
+ int result;
+ struct scsi_sense_hdr sshdr;
+
+ SCSI_LOG_IOCTL(1, sdev_printk(KERN_INFO, sdev,
+ "Trying ioctl with scsi command %d\n", *cmd));
+
+ result = scsi_execute_req(sdev, cmd, DMA_NONE, NULL, 0,
+ &sshdr, timeout, retries, NULL);
+
+ SCSI_LOG_IOCTL(2, sdev_printk(KERN_INFO, sdev,
+ "Ioctl returned 0x%x\n", result));
+
+ if ((driver_byte(result) & DRIVER_SENSE) &&
+ (scsi_sense_valid(&sshdr))) {
+ switch (sshdr.sense_key) {
+ case ILLEGAL_REQUEST:
+ if (cmd[0] == ALLOW_MEDIUM_REMOVAL)
+ sdev->lockable = 0;
+ else
+ sdev_printk(KERN_INFO, sdev,
+ "ioctl_internal_command: "
+ "ILLEGAL REQUEST "
+ "asc=0x%x ascq=0x%x\n",
+ sshdr.asc, sshdr.ascq);
+ break;
+ case NOT_READY: /* This happens if there is no disc in drive */
+ if (sdev->removable)
+ break;
+ case UNIT_ATTENTION:
+ if (sdev->removable) {
+ sdev->changed = 1;
+ result = 0; /* This is no longer considered an error */
+ break;
+ }
+ default: /* Fall through for non-removable media */
+ sdev_printk(KERN_INFO, sdev,
+ "ioctl_internal_command return code = %x\n",
+ result);
+ scsi_print_sense_hdr(sdev, NULL, &sshdr);
+ break;
+ }
+ }
+
+ SCSI_LOG_IOCTL(2, sdev_printk(KERN_INFO, sdev,
+ "IOCTL Releasing command\n"));
+ return result;
+}
+
+int scsi_set_medium_removal(struct scsi_device *sdev, char state)
+{
+ char scsi_cmd[MAX_COMMAND_SIZE];
+ int ret;
+
+ if (!sdev->removable || !sdev->lockable)
+ return 0;
+
+ scsi_cmd[0] = ALLOW_MEDIUM_REMOVAL;
+ scsi_cmd[1] = 0;
+ scsi_cmd[2] = 0;
+ scsi_cmd[3] = 0;
+ scsi_cmd[4] = state;
+ scsi_cmd[5] = 0;
+
+ ret = ioctl_internal_command(sdev, scsi_cmd,
+ IOCTL_NORMAL_TIMEOUT, NORMAL_RETRIES);
+ if (ret == 0)
+ sdev->locked = (state == SCSI_REMOVAL_PREVENT);
+ return ret;
+}
+EXPORT_SYMBOL(scsi_set_medium_removal);
+
+/*
+ * The scsi_ioctl_get_pci() function places into arg the value
+ * pci_dev::slot_name (8 characters) for the PCI device (if any).
+ * Returns: 0 on success
+ * -ENXIO if there isn't a PCI device pointer
+ * (could be because the SCSI driver hasn't been
+ * updated yet, or because it isn't a SCSI
+ * device)
+ * any copy_to_user() error on failure there
+ */
+static int scsi_ioctl_get_pci(struct scsi_device *sdev, void __user *arg)
+{
+ struct device *dev = scsi_get_device(sdev->host);
+ const char *name;
+
+ if (!dev)
+ return -ENXIO;
+
+ name = dev_name(dev);
+
+ /* compatibility with old ioctl which only returned
+ * 20 characters */
+ return copy_to_user(arg, name, min(strlen(name), (size_t)20))
+ ? -EFAULT: 0;
+}
+
+
+/**
+ * scsi_ioctl - Dispatch ioctl to scsi device
+ * @sdev: scsi device receiving ioctl
+ * @cmd: which ioctl is it
+ * @arg: data associated with ioctl
+ *
+ * Description: The scsi_ioctl() function differs from most ioctls in that it
+ * does not take a major/minor number as the dev field. Rather, it takes
+ * a pointer to a &struct scsi_device.
+ */
+int scsi_ioctl(struct scsi_device *sdev, int cmd, void __user *arg)
+{
+ char scsi_cmd[MAX_COMMAND_SIZE];
+
+ /* Check for deprecated ioctls ... all the ioctls which don't
+ * follow the new unique numbering scheme are deprecated */
+ switch (cmd) {
+ case SCSI_IOCTL_SEND_COMMAND:
+ case SCSI_IOCTL_TEST_UNIT_READY:
+ case SCSI_IOCTL_BENCHMARK_COMMAND:
+ case SCSI_IOCTL_SYNC:
+ case SCSI_IOCTL_START_UNIT:
+ case SCSI_IOCTL_STOP_UNIT:
+ printk(KERN_WARNING "program %s is using a deprecated SCSI "
+ "ioctl, please convert it to SG_IO\n", current->comm);
+ break;
+ default:
+ break;
+ }
+
+ switch (cmd) {
+ case SCSI_IOCTL_GET_IDLUN:
+ if (!access_ok(VERIFY_WRITE, arg, sizeof(struct scsi_idlun)))
+ return -EFAULT;
+
+ __put_user((sdev->id & 0xff)
+ + ((sdev->lun & 0xff) << 8)
+ + ((sdev->channel & 0xff) << 16)
+ + ((sdev->host->host_no & 0xff) << 24),
+ &((struct scsi_idlun __user *)arg)->dev_id);
+ __put_user(sdev->host->unique_id,
+ &((struct scsi_idlun __user *)arg)->host_unique_id);
+ return 0;
+ case SCSI_IOCTL_GET_BUS_NUMBER:
+ return put_user(sdev->host->host_no, (int __user *)arg);
+ case SCSI_IOCTL_PROBE_HOST:
+ return ioctl_probe(sdev->host, arg);
+ case SCSI_IOCTL_SEND_COMMAND:
+ if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
+ return -EACCES;
+ return sg_scsi_ioctl(sdev->request_queue, NULL, 0, arg);
+ case SCSI_IOCTL_DOORLOCK:
+ return scsi_set_medium_removal(sdev, SCSI_REMOVAL_PREVENT);
+ case SCSI_IOCTL_DOORUNLOCK:
+ return scsi_set_medium_removal(sdev, SCSI_REMOVAL_ALLOW);
+ case SCSI_IOCTL_TEST_UNIT_READY:
+ return scsi_test_unit_ready(sdev, IOCTL_NORMAL_TIMEOUT,
+ NORMAL_RETRIES, NULL);
+ case SCSI_IOCTL_START_UNIT:
+ scsi_cmd[0] = START_STOP;
+ scsi_cmd[1] = 0;
+ scsi_cmd[2] = scsi_cmd[3] = scsi_cmd[5] = 0;
+ scsi_cmd[4] = 1;
+ return ioctl_internal_command(sdev, scsi_cmd,
+ START_STOP_TIMEOUT, NORMAL_RETRIES);
+ case SCSI_IOCTL_STOP_UNIT:
+ scsi_cmd[0] = START_STOP;
+ scsi_cmd[1] = 0;
+ scsi_cmd[2] = scsi_cmd[3] = scsi_cmd[5] = 0;
+ scsi_cmd[4] = 0;
+ return ioctl_internal_command(sdev, scsi_cmd,
+ START_STOP_TIMEOUT, NORMAL_RETRIES);
+ case SCSI_IOCTL_GET_PCI:
+ return scsi_ioctl_get_pci(sdev, arg);
+ case SG_SCSI_RESET:
+ return scsi_ioctl_reset(sdev, arg);
+ default:
+ if (sdev->host->hostt->ioctl)
+ return sdev->host->hostt->ioctl(sdev, cmd, arg);
+ }
+ return -EINVAL;
+}
+EXPORT_SYMBOL(scsi_ioctl);
+
+/*
+ * We can process a reset even when a device isn't fully operable.
+ */
+int scsi_ioctl_block_when_processing_errors(struct scsi_device *sdev, int cmd,
+ bool ndelay)
+{
+ if (cmd == SG_SCSI_RESET && ndelay) {
+ if (scsi_host_in_recovery(sdev->host))
+ return -EAGAIN;
+ } else {
+ if (!scsi_block_when_processing_errors(sdev))
+ return -ENODEV;
+ }
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(scsi_ioctl_block_when_processing_errors);