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-rw-r--r--drivers/scsi/st.c4929
1 files changed, 4929 insertions, 0 deletions
diff --git a/drivers/scsi/st.c b/drivers/scsi/st.c
new file mode 100644
index 000000000..b90a440e1
--- /dev/null
+++ b/drivers/scsi/st.c
@@ -0,0 +1,4929 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ SCSI Tape Driver for Linux version 1.1 and newer. See the accompanying
+ file Documentation/scsi/st.rst for more information.
+
+ History:
+ Rewritten from Dwayne Forsyth's SCSI tape driver by Kai Makisara.
+ Contribution and ideas from several people including (in alphabetical
+ order) Klaus Ehrenfried, Eugene Exarevsky, Eric Lee Green, Wolfgang Denk,
+ Steve Hirsch, Andreas Koppenh"ofer, Michael Leodolter, Eyal Lebedinsky,
+ Michael Schaefer, J"org Weule, and Eric Youngdale.
+
+ Copyright 1992 - 2016 Kai Makisara
+ email Kai.Makisara@kolumbus.fi
+
+ Some small formal changes - aeb, 950809
+
+ Last modified: 18-JAN-1998 Richard Gooch <rgooch@atnf.csiro.au> Devfs support
+ */
+
+static const char *verstr = "20160209";
+
+#include <linux/module.h>
+
+#include <linux/compat.h>
+#include <linux/fs.h>
+#include <linux/kernel.h>
+#include <linux/sched/signal.h>
+#include <linux/mm.h>
+#include <linux/init.h>
+#include <linux/string.h>
+#include <linux/slab.h>
+#include <linux/errno.h>
+#include <linux/mtio.h>
+#include <linux/major.h>
+#include <linux/cdrom.h>
+#include <linux/ioctl.h>
+#include <linux/fcntl.h>
+#include <linux/spinlock.h>
+#include <linux/blkdev.h>
+#include <linux/moduleparam.h>
+#include <linux/cdev.h>
+#include <linux/idr.h>
+#include <linux/delay.h>
+#include <linux/mutex.h>
+
+#include <linux/uaccess.h>
+#include <asm/dma.h>
+#include <asm/unaligned.h>
+
+#include <scsi/scsi.h>
+#include <scsi/scsi_dbg.h>
+#include <scsi/scsi_device.h>
+#include <scsi/scsi_driver.h>
+#include <scsi/scsi_eh.h>
+#include <scsi/scsi_host.h>
+#include <scsi/scsi_ioctl.h>
+#include <scsi/sg.h>
+
+
+/* The driver prints some debugging information on the console if DEBUG
+ is defined and non-zero. */
+#define DEBUG 1
+#define NO_DEBUG 0
+
+#define ST_DEB_MSG KERN_NOTICE
+#if DEBUG
+/* The message level for the debug messages is currently set to KERN_NOTICE
+ so that people can easily see the messages. Later when the debugging messages
+ in the drivers are more widely classified, this may be changed to KERN_DEBUG. */
+#define DEB(a) a
+#define DEBC(a) if (debugging) { a ; }
+#else
+#define DEB(a)
+#define DEBC(a)
+#endif
+
+#define ST_KILOBYTE 1024
+
+#include "st_options.h"
+#include "st.h"
+
+static int buffer_kbs;
+static int max_sg_segs;
+static int try_direct_io = TRY_DIRECT_IO;
+static int try_rdio = 1;
+static int try_wdio = 1;
+static int debug_flag;
+
+static struct class st_sysfs_class;
+static const struct attribute_group *st_dev_groups[];
+static const struct attribute_group *st_drv_groups[];
+
+MODULE_AUTHOR("Kai Makisara");
+MODULE_DESCRIPTION("SCSI tape (st) driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS_CHARDEV_MAJOR(SCSI_TAPE_MAJOR);
+MODULE_ALIAS_SCSI_DEVICE(TYPE_TAPE);
+
+/* Set 'perm' (4th argument) to 0 to disable module_param's definition
+ * of sysfs parameters (which module_param doesn't yet support).
+ * Sysfs parameters defined explicitly later.
+ */
+module_param_named(buffer_kbs, buffer_kbs, int, 0);
+MODULE_PARM_DESC(buffer_kbs, "Default driver buffer size for fixed block mode (KB; 32)");
+module_param_named(max_sg_segs, max_sg_segs, int, 0);
+MODULE_PARM_DESC(max_sg_segs, "Maximum number of scatter/gather segments to use (256)");
+module_param_named(try_direct_io, try_direct_io, int, 0);
+MODULE_PARM_DESC(try_direct_io, "Try direct I/O between user buffer and tape drive (1)");
+module_param_named(debug_flag, debug_flag, int, 0);
+MODULE_PARM_DESC(debug_flag, "Enable DEBUG, same as setting debugging=1");
+
+
+/* Extra parameters for testing */
+module_param_named(try_rdio, try_rdio, int, 0);
+MODULE_PARM_DESC(try_rdio, "Try direct read i/o when possible");
+module_param_named(try_wdio, try_wdio, int, 0);
+MODULE_PARM_DESC(try_wdio, "Try direct write i/o when possible");
+
+#ifndef MODULE
+static int write_threshold_kbs; /* retained for compatibility */
+static struct st_dev_parm {
+ char *name;
+ int *val;
+} parms[] __initdata = {
+ {
+ "buffer_kbs", &buffer_kbs
+ },
+ { /* Retained for compatibility with 2.4 */
+ "write_threshold_kbs", &write_threshold_kbs
+ },
+ {
+ "max_sg_segs", NULL
+ },
+ {
+ "try_direct_io", &try_direct_io
+ },
+ {
+ "debug_flag", &debug_flag
+ }
+};
+#endif
+
+/* Restrict the number of modes so that names for all are assigned */
+#if ST_NBR_MODES > 16
+#error "Maximum number of modes is 16"
+#endif
+/* Bit reversed order to get same names for same minors with all
+ mode counts */
+static const char *st_formats[] = {
+ "", "r", "k", "s", "l", "t", "o", "u",
+ "m", "v", "p", "x", "a", "y", "q", "z"};
+
+/* The default definitions have been moved to st_options.h */
+
+#define ST_FIXED_BUFFER_SIZE (ST_FIXED_BUFFER_BLOCKS * ST_KILOBYTE)
+
+/* The buffer size should fit into the 24 bits for length in the
+ 6-byte SCSI read and write commands. */
+#if ST_FIXED_BUFFER_SIZE >= (2 << 24 - 1)
+#error "Buffer size should not exceed (2 << 24 - 1) bytes!"
+#endif
+
+static int debugging = DEBUG;
+
+#define MAX_RETRIES 0
+#define MAX_WRITE_RETRIES 0
+#define MAX_READY_RETRIES 0
+#define NO_TAPE NOT_READY
+
+#define ST_TIMEOUT (900 * HZ)
+#define ST_LONG_TIMEOUT (14000 * HZ)
+
+/* Remove mode bits and auto-rewind bit (7) */
+#define TAPE_NR(x) ( ((iminor(x) & ~255) >> (ST_NBR_MODE_BITS + 1)) | \
+ (iminor(x) & ((1 << ST_MODE_SHIFT)-1)))
+#define TAPE_MODE(x) ((iminor(x) & ST_MODE_MASK) >> ST_MODE_SHIFT)
+
+/* Construct the minor number from the device (d), mode (m), and non-rewind (n) data */
+#define TAPE_MINOR(d, m, n) (((d & ~(255 >> (ST_NBR_MODE_BITS + 1))) << (ST_NBR_MODE_BITS + 1)) | \
+ (d & (255 >> (ST_NBR_MODE_BITS + 1))) | (m << ST_MODE_SHIFT) | ((n != 0) << 7) )
+
+/* Internal ioctl to set both density (uppermost 8 bits) and blocksize (lower
+ 24 bits) */
+#define SET_DENS_AND_BLK 0x10001
+
+static int st_fixed_buffer_size = ST_FIXED_BUFFER_SIZE;
+static int st_max_sg_segs = ST_MAX_SG;
+
+static int modes_defined;
+
+static int enlarge_buffer(struct st_buffer *, int);
+static void clear_buffer(struct st_buffer *);
+static void normalize_buffer(struct st_buffer *);
+static int append_to_buffer(const char __user *, struct st_buffer *, int);
+static int from_buffer(struct st_buffer *, char __user *, int);
+static void move_buffer_data(struct st_buffer *, int);
+
+static int sgl_map_user_pages(struct st_buffer *, const unsigned int,
+ unsigned long, size_t, int);
+static int sgl_unmap_user_pages(struct st_buffer *, const unsigned int, int);
+
+static int st_probe(struct device *);
+static int st_remove(struct device *);
+
+static struct scsi_driver st_template = {
+ .gendrv = {
+ .name = "st",
+ .owner = THIS_MODULE,
+ .probe = st_probe,
+ .remove = st_remove,
+ .groups = st_drv_groups,
+ },
+};
+
+static int st_compression(struct scsi_tape *, int);
+
+static int find_partition(struct scsi_tape *);
+static int switch_partition(struct scsi_tape *);
+
+static int st_int_ioctl(struct scsi_tape *, unsigned int, unsigned long);
+
+static void scsi_tape_release(struct kref *);
+
+#define to_scsi_tape(obj) container_of(obj, struct scsi_tape, kref)
+
+static DEFINE_MUTEX(st_ref_mutex);
+static DEFINE_SPINLOCK(st_index_lock);
+static DEFINE_SPINLOCK(st_use_lock);
+static DEFINE_IDR(st_index_idr);
+
+
+
+#ifndef SIGS_FROM_OSST
+#define SIGS_FROM_OSST \
+ {"OnStream", "SC-", "", "osst"}, \
+ {"OnStream", "DI-", "", "osst"}, \
+ {"OnStream", "DP-", "", "osst"}, \
+ {"OnStream", "USB", "", "osst"}, \
+ {"OnStream", "FW-", "", "osst"}
+#endif
+
+static struct scsi_tape *scsi_tape_get(int dev)
+{
+ struct scsi_tape *STp = NULL;
+
+ mutex_lock(&st_ref_mutex);
+ spin_lock(&st_index_lock);
+
+ STp = idr_find(&st_index_idr, dev);
+ if (!STp) goto out;
+
+ kref_get(&STp->kref);
+
+ if (!STp->device)
+ goto out_put;
+
+ if (scsi_device_get(STp->device))
+ goto out_put;
+
+ goto out;
+
+out_put:
+ kref_put(&STp->kref, scsi_tape_release);
+ STp = NULL;
+out:
+ spin_unlock(&st_index_lock);
+ mutex_unlock(&st_ref_mutex);
+ return STp;
+}
+
+static void scsi_tape_put(struct scsi_tape *STp)
+{
+ struct scsi_device *sdev = STp->device;
+
+ mutex_lock(&st_ref_mutex);
+ kref_put(&STp->kref, scsi_tape_release);
+ scsi_device_put(sdev);
+ mutex_unlock(&st_ref_mutex);
+}
+
+struct st_reject_data {
+ char *vendor;
+ char *model;
+ char *rev;
+ char *driver_hint; /* Name of the correct driver, NULL if unknown */
+};
+
+static struct st_reject_data reject_list[] = {
+ /* {"XXX", "Yy-", "", NULL}, example */
+ SIGS_FROM_OSST,
+ {NULL, }};
+
+/* If the device signature is on the list of incompatible drives, the
+ function returns a pointer to the name of the correct driver (if known) */
+static char * st_incompatible(struct scsi_device* SDp)
+{
+ struct st_reject_data *rp;
+
+ for (rp=&(reject_list[0]); rp->vendor != NULL; rp++)
+ if (!strncmp(rp->vendor, SDp->vendor, strlen(rp->vendor)) &&
+ !strncmp(rp->model, SDp->model, strlen(rp->model)) &&
+ !strncmp(rp->rev, SDp->rev, strlen(rp->rev))) {
+ if (rp->driver_hint)
+ return rp->driver_hint;
+ else
+ return "unknown";
+ }
+ return NULL;
+}
+
+
+#define st_printk(prefix, t, fmt, a...) \
+ sdev_prefix_printk(prefix, (t)->device, (t)->name, fmt, ##a)
+#ifdef DEBUG
+#define DEBC_printk(t, fmt, a...) \
+ if (debugging) { st_printk(ST_DEB_MSG, t, fmt, ##a ); }
+#else
+#define DEBC_printk(t, fmt, a...)
+#endif
+
+static void st_analyze_sense(struct st_request *SRpnt, struct st_cmdstatus *s)
+{
+ const u8 *ucp;
+ const u8 *sense = SRpnt->sense;
+
+ s->have_sense = scsi_normalize_sense(SRpnt->sense,
+ SCSI_SENSE_BUFFERSIZE, &s->sense_hdr);
+ s->flags = 0;
+
+ if (s->have_sense) {
+ s->deferred = 0;
+ s->remainder_valid =
+ scsi_get_sense_info_fld(sense, SCSI_SENSE_BUFFERSIZE, &s->uremainder64);
+ switch (sense[0] & 0x7f) {
+ case 0x71:
+ s->deferred = 1;
+ fallthrough;
+ case 0x70:
+ s->fixed_format = 1;
+ s->flags = sense[2] & 0xe0;
+ break;
+ case 0x73:
+ s->deferred = 1;
+ fallthrough;
+ case 0x72:
+ s->fixed_format = 0;
+ ucp = scsi_sense_desc_find(sense, SCSI_SENSE_BUFFERSIZE, 4);
+ s->flags = ucp ? (ucp[3] & 0xe0) : 0;
+ break;
+ }
+ }
+}
+
+
+/* Convert the result to success code */
+static int st_chk_result(struct scsi_tape *STp, struct st_request * SRpnt)
+{
+ int result = SRpnt->result;
+ u8 scode;
+ DEB(const char *stp;)
+ char *name = STp->name;
+ struct st_cmdstatus *cmdstatp;
+
+ if (!result)
+ return 0;
+
+ cmdstatp = &STp->buffer->cmdstat;
+ st_analyze_sense(SRpnt, cmdstatp);
+
+ if (cmdstatp->have_sense)
+ scode = STp->buffer->cmdstat.sense_hdr.sense_key;
+ else
+ scode = 0;
+
+ DEB(
+ if (debugging) {
+ st_printk(ST_DEB_MSG, STp,
+ "Error: %x, cmd: %x %x %x %x %x %x\n", result,
+ SRpnt->cmd[0], SRpnt->cmd[1], SRpnt->cmd[2],
+ SRpnt->cmd[3], SRpnt->cmd[4], SRpnt->cmd[5]);
+ if (cmdstatp->have_sense)
+ __scsi_print_sense(STp->device, name,
+ SRpnt->sense, SCSI_SENSE_BUFFERSIZE);
+ } ) /* end DEB */
+ if (!debugging) { /* Abnormal conditions for tape */
+ if (!cmdstatp->have_sense)
+ st_printk(KERN_WARNING, STp,
+ "Error %x (driver bt 0, host bt 0x%x).\n",
+ result, host_byte(result));
+ else if (cmdstatp->have_sense &&
+ scode != NO_SENSE &&
+ scode != RECOVERED_ERROR &&
+ /* scode != UNIT_ATTENTION && */
+ scode != BLANK_CHECK &&
+ scode != VOLUME_OVERFLOW &&
+ SRpnt->cmd[0] != MODE_SENSE &&
+ SRpnt->cmd[0] != TEST_UNIT_READY) {
+
+ __scsi_print_sense(STp->device, name,
+ SRpnt->sense, SCSI_SENSE_BUFFERSIZE);
+ }
+ }
+
+ if (cmdstatp->fixed_format &&
+ STp->cln_mode >= EXTENDED_SENSE_START) { /* Only fixed format sense */
+ if (STp->cln_sense_value)
+ STp->cleaning_req |= ((SRpnt->sense[STp->cln_mode] &
+ STp->cln_sense_mask) == STp->cln_sense_value);
+ else
+ STp->cleaning_req |= ((SRpnt->sense[STp->cln_mode] &
+ STp->cln_sense_mask) != 0);
+ }
+ if (cmdstatp->have_sense &&
+ cmdstatp->sense_hdr.asc == 0 && cmdstatp->sense_hdr.ascq == 0x17)
+ STp->cleaning_req = 1; /* ASC and ASCQ => cleaning requested */
+
+ STp->pos_unknown |= STp->device->was_reset;
+
+ if (cmdstatp->have_sense &&
+ scode == RECOVERED_ERROR
+#if ST_RECOVERED_WRITE_FATAL
+ && SRpnt->cmd[0] != WRITE_6
+ && SRpnt->cmd[0] != WRITE_FILEMARKS
+#endif
+ ) {
+ STp->recover_count++;
+ STp->recover_reg++;
+
+ DEB(
+ if (debugging) {
+ if (SRpnt->cmd[0] == READ_6)
+ stp = "read";
+ else if (SRpnt->cmd[0] == WRITE_6)
+ stp = "write";
+ else
+ stp = "ioctl";
+ st_printk(ST_DEB_MSG, STp,
+ "Recovered %s error (%d).\n",
+ stp, STp->recover_count);
+ } ) /* end DEB */
+
+ if (cmdstatp->flags == 0)
+ return 0;
+ }
+ return (-EIO);
+}
+
+static struct st_request *st_allocate_request(struct scsi_tape *stp)
+{
+ struct st_request *streq;
+
+ streq = kzalloc(sizeof(*streq), GFP_KERNEL);
+ if (streq)
+ streq->stp = stp;
+ else {
+ st_printk(KERN_ERR, stp,
+ "Can't get SCSI request.\n");
+ if (signal_pending(current))
+ stp->buffer->syscall_result = -EINTR;
+ else
+ stp->buffer->syscall_result = -EBUSY;
+ }
+
+ return streq;
+}
+
+static void st_release_request(struct st_request *streq)
+{
+ kfree(streq);
+}
+
+static void st_do_stats(struct scsi_tape *STp, struct request *req)
+{
+ struct scsi_cmnd *scmd = blk_mq_rq_to_pdu(req);
+ ktime_t now;
+
+ now = ktime_get();
+ if (scmd->cmnd[0] == WRITE_6) {
+ now = ktime_sub(now, STp->stats->write_time);
+ atomic64_add(ktime_to_ns(now), &STp->stats->tot_write_time);
+ atomic64_add(ktime_to_ns(now), &STp->stats->tot_io_time);
+ atomic64_inc(&STp->stats->write_cnt);
+ if (scmd->result) {
+ atomic64_add(atomic_read(&STp->stats->last_write_size)
+ - STp->buffer->cmdstat.residual,
+ &STp->stats->write_byte_cnt);
+ if (STp->buffer->cmdstat.residual > 0)
+ atomic64_inc(&STp->stats->resid_cnt);
+ } else
+ atomic64_add(atomic_read(&STp->stats->last_write_size),
+ &STp->stats->write_byte_cnt);
+ } else if (scmd->cmnd[0] == READ_6) {
+ now = ktime_sub(now, STp->stats->read_time);
+ atomic64_add(ktime_to_ns(now), &STp->stats->tot_read_time);
+ atomic64_add(ktime_to_ns(now), &STp->stats->tot_io_time);
+ atomic64_inc(&STp->stats->read_cnt);
+ if (scmd->result) {
+ atomic64_add(atomic_read(&STp->stats->last_read_size)
+ - STp->buffer->cmdstat.residual,
+ &STp->stats->read_byte_cnt);
+ if (STp->buffer->cmdstat.residual > 0)
+ atomic64_inc(&STp->stats->resid_cnt);
+ } else
+ atomic64_add(atomic_read(&STp->stats->last_read_size),
+ &STp->stats->read_byte_cnt);
+ } else {
+ now = ktime_sub(now, STp->stats->other_time);
+ atomic64_add(ktime_to_ns(now), &STp->stats->tot_io_time);
+ atomic64_inc(&STp->stats->other_cnt);
+ }
+ atomic64_dec(&STp->stats->in_flight);
+}
+
+static enum rq_end_io_ret st_scsi_execute_end(struct request *req,
+ blk_status_t status)
+{
+ struct scsi_cmnd *scmd = blk_mq_rq_to_pdu(req);
+ struct st_request *SRpnt = req->end_io_data;
+ struct scsi_tape *STp = SRpnt->stp;
+ struct bio *tmp;
+
+ STp->buffer->cmdstat.midlevel_result = SRpnt->result = scmd->result;
+ STp->buffer->cmdstat.residual = scmd->resid_len;
+
+ st_do_stats(STp, req);
+
+ tmp = SRpnt->bio;
+ if (scmd->sense_len)
+ memcpy(SRpnt->sense, scmd->sense_buffer, SCSI_SENSE_BUFFERSIZE);
+ if (SRpnt->waiting)
+ complete(SRpnt->waiting);
+
+ blk_rq_unmap_user(tmp);
+ blk_mq_free_request(req);
+ return RQ_END_IO_NONE;
+}
+
+static int st_scsi_execute(struct st_request *SRpnt, const unsigned char *cmd,
+ int data_direction, void *buffer, unsigned bufflen,
+ int timeout, int retries)
+{
+ struct request *req;
+ struct rq_map_data *mdata = &SRpnt->stp->buffer->map_data;
+ int err = 0;
+ struct scsi_tape *STp = SRpnt->stp;
+ struct scsi_cmnd *scmd;
+
+ req = scsi_alloc_request(SRpnt->stp->device->request_queue,
+ data_direction == DMA_TO_DEVICE ?
+ REQ_OP_DRV_OUT : REQ_OP_DRV_IN, 0);
+ if (IS_ERR(req))
+ return PTR_ERR(req);
+ scmd = blk_mq_rq_to_pdu(req);
+ req->rq_flags |= RQF_QUIET;
+
+ mdata->null_mapped = 1;
+
+ if (bufflen) {
+ err = blk_rq_map_user(req->q, req, mdata, NULL, bufflen,
+ GFP_KERNEL);
+ if (err) {
+ blk_mq_free_request(req);
+ return err;
+ }
+ }
+
+ atomic64_inc(&STp->stats->in_flight);
+ if (cmd[0] == WRITE_6) {
+ atomic_set(&STp->stats->last_write_size, bufflen);
+ STp->stats->write_time = ktime_get();
+ } else if (cmd[0] == READ_6) {
+ atomic_set(&STp->stats->last_read_size, bufflen);
+ STp->stats->read_time = ktime_get();
+ } else {
+ STp->stats->other_time = ktime_get();
+ }
+
+ SRpnt->bio = req->bio;
+ scmd->cmd_len = COMMAND_SIZE(cmd[0]);
+ memcpy(scmd->cmnd, cmd, scmd->cmd_len);
+ req->timeout = timeout;
+ scmd->allowed = retries;
+ req->end_io = st_scsi_execute_end;
+ req->end_io_data = SRpnt;
+
+ blk_execute_rq_nowait(req, true);
+ return 0;
+}
+
+/* Do the scsi command. Waits until command performed if do_wait is true.
+ Otherwise write_behind_check() is used to check that the command
+ has finished. */
+static struct st_request *
+st_do_scsi(struct st_request * SRpnt, struct scsi_tape * STp, unsigned char *cmd,
+ int bytes, int direction, int timeout, int retries, int do_wait)
+{
+ struct completion *waiting;
+ struct rq_map_data *mdata = &STp->buffer->map_data;
+ int ret;
+
+ /* if async, make sure there's no command outstanding */
+ if (!do_wait && ((STp->buffer)->last_SRpnt)) {
+ st_printk(KERN_ERR, STp,
+ "Async command already active.\n");
+ if (signal_pending(current))
+ (STp->buffer)->syscall_result = (-EINTR);
+ else
+ (STp->buffer)->syscall_result = (-EBUSY);
+ return NULL;
+ }
+
+ if (!SRpnt) {
+ SRpnt = st_allocate_request(STp);
+ if (!SRpnt)
+ return NULL;
+ }
+
+ /* If async IO, set last_SRpnt. This ptr tells write_behind_check
+ which IO is outstanding. It's nulled out when the IO completes. */
+ if (!do_wait)
+ (STp->buffer)->last_SRpnt = SRpnt;
+
+ waiting = &STp->wait;
+ init_completion(waiting);
+ SRpnt->waiting = waiting;
+
+ if (STp->buffer->do_dio) {
+ mdata->page_order = 0;
+ mdata->nr_entries = STp->buffer->sg_segs;
+ mdata->pages = STp->buffer->mapped_pages;
+ } else {
+ mdata->page_order = STp->buffer->reserved_page_order;
+ mdata->nr_entries =
+ DIV_ROUND_UP(bytes, PAGE_SIZE << mdata->page_order);
+ mdata->pages = STp->buffer->reserved_pages;
+ mdata->offset = 0;
+ }
+
+ memcpy(SRpnt->cmd, cmd, sizeof(SRpnt->cmd));
+ STp->buffer->cmdstat.have_sense = 0;
+ STp->buffer->syscall_result = 0;
+
+ ret = st_scsi_execute(SRpnt, cmd, direction, NULL, bytes, timeout,
+ retries);
+ if (ret) {
+ /* could not allocate the buffer or request was too large */
+ (STp->buffer)->syscall_result = (-EBUSY);
+ (STp->buffer)->last_SRpnt = NULL;
+ } else if (do_wait) {
+ wait_for_completion(waiting);
+ SRpnt->waiting = NULL;
+ (STp->buffer)->syscall_result = st_chk_result(STp, SRpnt);
+ }
+
+ return SRpnt;
+}
+
+
+/* Handle the write-behind checking (waits for completion). Returns -ENOSPC if
+ write has been correct but EOM early warning reached, -EIO if write ended in
+ error or zero if write successful. Asynchronous writes are used only in
+ variable block mode. */
+static int write_behind_check(struct scsi_tape * STp)
+{
+ int retval = 0;
+ struct st_buffer *STbuffer;
+ struct st_partstat *STps;
+ struct st_cmdstatus *cmdstatp;
+ struct st_request *SRpnt;
+
+ STbuffer = STp->buffer;
+ if (!STbuffer->writing)
+ return 0;
+
+ DEB(
+ if (STp->write_pending)
+ STp->nbr_waits++;
+ else
+ STp->nbr_finished++;
+ ) /* end DEB */
+
+ wait_for_completion(&(STp->wait));
+ SRpnt = STbuffer->last_SRpnt;
+ STbuffer->last_SRpnt = NULL;
+ SRpnt->waiting = NULL;
+
+ (STp->buffer)->syscall_result = st_chk_result(STp, SRpnt);
+ st_release_request(SRpnt);
+
+ STbuffer->buffer_bytes -= STbuffer->writing;
+ STps = &(STp->ps[STp->partition]);
+ if (STps->drv_block >= 0) {
+ if (STp->block_size == 0)
+ STps->drv_block++;
+ else
+ STps->drv_block += STbuffer->writing / STp->block_size;
+ }
+
+ cmdstatp = &STbuffer->cmdstat;
+ if (STbuffer->syscall_result) {
+ retval = -EIO;
+ if (cmdstatp->have_sense && !cmdstatp->deferred &&
+ (cmdstatp->flags & SENSE_EOM) &&
+ (cmdstatp->sense_hdr.sense_key == NO_SENSE ||
+ cmdstatp->sense_hdr.sense_key == RECOVERED_ERROR)) {
+ /* EOM at write-behind, has all data been written? */
+ if (!cmdstatp->remainder_valid ||
+ cmdstatp->uremainder64 == 0)
+ retval = -ENOSPC;
+ }
+ if (retval == -EIO)
+ STps->drv_block = -1;
+ }
+ STbuffer->writing = 0;
+
+ DEB(if (debugging && retval)
+ st_printk(ST_DEB_MSG, STp,
+ "Async write error %x, return value %d.\n",
+ STbuffer->cmdstat.midlevel_result, retval);) /* end DEB */
+
+ return retval;
+}
+
+
+/* Step over EOF if it has been inadvertently crossed (ioctl not used because
+ it messes up the block number). */
+static int cross_eof(struct scsi_tape * STp, int forward)
+{
+ struct st_request *SRpnt;
+ unsigned char cmd[MAX_COMMAND_SIZE];
+
+ cmd[0] = SPACE;
+ cmd[1] = 0x01; /* Space FileMarks */
+ if (forward) {
+ cmd[2] = cmd[3] = 0;
+ cmd[4] = 1;
+ } else
+ cmd[2] = cmd[3] = cmd[4] = 0xff; /* -1 filemarks */
+ cmd[5] = 0;
+
+ DEBC_printk(STp, "Stepping over filemark %s.\n",
+ forward ? "forward" : "backward");
+
+ SRpnt = st_do_scsi(NULL, STp, cmd, 0, DMA_NONE,
+ STp->device->request_queue->rq_timeout,
+ MAX_RETRIES, 1);
+ if (!SRpnt)
+ return (STp->buffer)->syscall_result;
+
+ st_release_request(SRpnt);
+ SRpnt = NULL;
+
+ if ((STp->buffer)->cmdstat.midlevel_result != 0)
+ st_printk(KERN_ERR, STp,
+ "Stepping over filemark %s failed.\n",
+ forward ? "forward" : "backward");
+
+ return (STp->buffer)->syscall_result;
+}
+
+
+/* Flush the write buffer (never need to write if variable blocksize). */
+static int st_flush_write_buffer(struct scsi_tape * STp)
+{
+ int transfer, blks;
+ int result;
+ unsigned char cmd[MAX_COMMAND_SIZE];
+ struct st_request *SRpnt;
+ struct st_partstat *STps;
+
+ result = write_behind_check(STp);
+ if (result)
+ return result;
+
+ result = 0;
+ if (STp->dirty == 1) {
+
+ transfer = STp->buffer->buffer_bytes;
+ DEBC_printk(STp, "Flushing %d bytes.\n", transfer);
+
+ memset(cmd, 0, MAX_COMMAND_SIZE);
+ cmd[0] = WRITE_6;
+ cmd[1] = 1;
+ blks = transfer / STp->block_size;
+ cmd[2] = blks >> 16;
+ cmd[3] = blks >> 8;
+ cmd[4] = blks;
+
+ SRpnt = st_do_scsi(NULL, STp, cmd, transfer, DMA_TO_DEVICE,
+ STp->device->request_queue->rq_timeout,
+ MAX_WRITE_RETRIES, 1);
+ if (!SRpnt)
+ return (STp->buffer)->syscall_result;
+
+ STps = &(STp->ps[STp->partition]);
+ if ((STp->buffer)->syscall_result != 0) {
+ struct st_cmdstatus *cmdstatp = &STp->buffer->cmdstat;
+
+ if (cmdstatp->have_sense && !cmdstatp->deferred &&
+ (cmdstatp->flags & SENSE_EOM) &&
+ (cmdstatp->sense_hdr.sense_key == NO_SENSE ||
+ cmdstatp->sense_hdr.sense_key == RECOVERED_ERROR) &&
+ (!cmdstatp->remainder_valid ||
+ cmdstatp->uremainder64 == 0)) { /* All written at EOM early warning */
+ STp->dirty = 0;
+ (STp->buffer)->buffer_bytes = 0;
+ if (STps->drv_block >= 0)
+ STps->drv_block += blks;
+ result = (-ENOSPC);
+ } else {
+ st_printk(KERN_ERR, STp, "Error on flush.\n");
+ STps->drv_block = (-1);
+ result = (-EIO);
+ }
+ } else {
+ if (STps->drv_block >= 0)
+ STps->drv_block += blks;
+ STp->dirty = 0;
+ (STp->buffer)->buffer_bytes = 0;
+ }
+ st_release_request(SRpnt);
+ SRpnt = NULL;
+ }
+ return result;
+}
+
+
+/* Flush the tape buffer. The tape will be positioned correctly unless
+ seek_next is true. */
+static int flush_buffer(struct scsi_tape *STp, int seek_next)
+{
+ int backspace, result;
+ struct st_partstat *STps;
+
+ /*
+ * If there was a bus reset, block further access
+ * to this device.
+ */
+ if (STp->pos_unknown)
+ return (-EIO);
+
+ if (STp->ready != ST_READY)
+ return 0;
+ STps = &(STp->ps[STp->partition]);
+ if (STps->rw == ST_WRITING) /* Writing */
+ return st_flush_write_buffer(STp);
+
+ if (STp->block_size == 0)
+ return 0;
+
+ backspace = ((STp->buffer)->buffer_bytes +
+ (STp->buffer)->read_pointer) / STp->block_size -
+ ((STp->buffer)->read_pointer + STp->block_size - 1) /
+ STp->block_size;
+ (STp->buffer)->buffer_bytes = 0;
+ (STp->buffer)->read_pointer = 0;
+ result = 0;
+ if (!seek_next) {
+ if (STps->eof == ST_FM_HIT) {
+ result = cross_eof(STp, 0); /* Back over the EOF hit */
+ if (!result)
+ STps->eof = ST_NOEOF;
+ else {
+ if (STps->drv_file >= 0)
+ STps->drv_file++;
+ STps->drv_block = 0;
+ }
+ }
+ if (!result && backspace > 0)
+ result = st_int_ioctl(STp, MTBSR, backspace);
+ } else if (STps->eof == ST_FM_HIT) {
+ if (STps->drv_file >= 0)
+ STps->drv_file++;
+ STps->drv_block = 0;
+ STps->eof = ST_NOEOF;
+ }
+ return result;
+
+}
+
+/* Set the mode parameters */
+static int set_mode_densblk(struct scsi_tape * STp, struct st_modedef * STm)
+{
+ int set_it = 0;
+ unsigned long arg;
+
+ if (!STp->density_changed &&
+ STm->default_density >= 0 &&
+ STm->default_density != STp->density) {
+ arg = STm->default_density;
+ set_it = 1;
+ } else
+ arg = STp->density;
+ arg <<= MT_ST_DENSITY_SHIFT;
+ if (!STp->blksize_changed &&
+ STm->default_blksize >= 0 &&
+ STm->default_blksize != STp->block_size) {
+ arg |= STm->default_blksize;
+ set_it = 1;
+ } else
+ arg |= STp->block_size;
+ if (set_it &&
+ st_int_ioctl(STp, SET_DENS_AND_BLK, arg)) {
+ st_printk(KERN_WARNING, STp,
+ "Can't set default block size to %d bytes "
+ "and density %x.\n",
+ STm->default_blksize, STm->default_density);
+ if (modes_defined)
+ return (-EINVAL);
+ }
+ return 0;
+}
+
+
+/* Lock or unlock the drive door. Don't use when st_request allocated. */
+static int do_door_lock(struct scsi_tape * STp, int do_lock)
+{
+ int retval;
+
+ DEBC_printk(STp, "%socking drive door.\n", do_lock ? "L" : "Unl");
+
+ retval = scsi_set_medium_removal(STp->device,
+ do_lock ? SCSI_REMOVAL_PREVENT : SCSI_REMOVAL_ALLOW);
+ if (!retval)
+ STp->door_locked = do_lock ? ST_LOCKED_EXPLICIT : ST_UNLOCKED;
+ else
+ STp->door_locked = ST_LOCK_FAILS;
+ return retval;
+}
+
+
+/* Set the internal state after reset */
+static void reset_state(struct scsi_tape *STp)
+{
+ int i;
+ struct st_partstat *STps;
+
+ STp->pos_unknown = 0;
+ for (i = 0; i < ST_NBR_PARTITIONS; i++) {
+ STps = &(STp->ps[i]);
+ STps->rw = ST_IDLE;
+ STps->eof = ST_NOEOF;
+ STps->at_sm = 0;
+ STps->last_block_valid = 0;
+ STps->drv_block = -1;
+ STps->drv_file = -1;
+ }
+ if (STp->can_partitions) {
+ STp->partition = find_partition(STp);
+ if (STp->partition < 0)
+ STp->partition = 0;
+ STp->new_partition = STp->partition;
+ }
+}
+
+/* Test if the drive is ready. Returns either one of the codes below or a negative system
+ error code. */
+#define CHKRES_READY 0
+#define CHKRES_NEW_SESSION 1
+#define CHKRES_NOT_READY 2
+#define CHKRES_NO_TAPE 3
+
+#define MAX_ATTENTIONS 10
+
+static int test_ready(struct scsi_tape *STp, int do_wait)
+{
+ int attentions, waits, max_wait, scode;
+ int retval = CHKRES_READY, new_session = 0;
+ unsigned char cmd[MAX_COMMAND_SIZE];
+ struct st_request *SRpnt = NULL;
+ struct st_cmdstatus *cmdstatp = &STp->buffer->cmdstat;
+
+ max_wait = do_wait ? ST_BLOCK_SECONDS : 0;
+
+ for (attentions=waits=0; ; ) {
+ memset((void *) &cmd[0], 0, MAX_COMMAND_SIZE);
+ cmd[0] = TEST_UNIT_READY;
+ SRpnt = st_do_scsi(SRpnt, STp, cmd, 0, DMA_NONE,
+ STp->long_timeout, MAX_READY_RETRIES, 1);
+
+ if (!SRpnt) {
+ retval = (STp->buffer)->syscall_result;
+ break;
+ }
+
+ if (cmdstatp->have_sense) {
+
+ scode = cmdstatp->sense_hdr.sense_key;
+
+ if (scode == UNIT_ATTENTION) { /* New media? */
+ new_session = 1;
+ if (attentions < MAX_ATTENTIONS) {
+ attentions++;
+ continue;
+ }
+ else {
+ retval = (-EIO);
+ break;
+ }
+ }
+
+ if (scode == NOT_READY) {
+ if (waits < max_wait) {
+ if (msleep_interruptible(1000)) {
+ retval = (-EINTR);
+ break;
+ }
+ waits++;
+ continue;
+ }
+ else {
+ if ((STp->device)->scsi_level >= SCSI_2 &&
+ cmdstatp->sense_hdr.asc == 0x3a) /* Check ASC */
+ retval = CHKRES_NO_TAPE;
+ else
+ retval = CHKRES_NOT_READY;
+ break;
+ }
+ }
+ }
+
+ retval = (STp->buffer)->syscall_result;
+ if (!retval)
+ retval = new_session ? CHKRES_NEW_SESSION : CHKRES_READY;
+ break;
+ }
+
+ if (SRpnt != NULL)
+ st_release_request(SRpnt);
+ return retval;
+}
+
+
+/* See if the drive is ready and gather information about the tape. Return values:
+ < 0 negative error code from errno.h
+ 0 drive ready
+ 1 drive not ready (possibly no tape)
+*/
+static int check_tape(struct scsi_tape *STp, struct file *filp)
+{
+ int i, retval, new_session = 0, do_wait;
+ unsigned char cmd[MAX_COMMAND_SIZE], saved_cleaning;
+ unsigned short st_flags = filp->f_flags;
+ struct st_request *SRpnt = NULL;
+ struct st_modedef *STm;
+ struct st_partstat *STps;
+ struct inode *inode = file_inode(filp);
+ int mode = TAPE_MODE(inode);
+
+ STp->ready = ST_READY;
+
+ if (mode != STp->current_mode) {
+ DEBC_printk(STp, "Mode change from %d to %d.\n",
+ STp->current_mode, mode);
+ new_session = 1;
+ STp->current_mode = mode;
+ }
+ STm = &(STp->modes[STp->current_mode]);
+
+ saved_cleaning = STp->cleaning_req;
+ STp->cleaning_req = 0;
+
+ do_wait = ((filp->f_flags & O_NONBLOCK) == 0);
+ retval = test_ready(STp, do_wait);
+
+ if (retval < 0)
+ goto err_out;
+
+ if (retval == CHKRES_NEW_SESSION) {
+ STp->pos_unknown = 0;
+ STp->partition = STp->new_partition = 0;
+ if (STp->can_partitions)
+ STp->nbr_partitions = 1; /* This guess will be updated later
+ if necessary */
+ for (i = 0; i < ST_NBR_PARTITIONS; i++) {
+ STps = &(STp->ps[i]);
+ STps->rw = ST_IDLE;
+ STps->eof = ST_NOEOF;
+ STps->at_sm = 0;
+ STps->last_block_valid = 0;
+ STps->drv_block = 0;
+ STps->drv_file = 0;
+ }
+ new_session = 1;
+ }
+ else {
+ STp->cleaning_req |= saved_cleaning;
+
+ if (retval == CHKRES_NOT_READY || retval == CHKRES_NO_TAPE) {
+ if (retval == CHKRES_NO_TAPE)
+ STp->ready = ST_NO_TAPE;
+ else
+ STp->ready = ST_NOT_READY;
+
+ STp->density = 0; /* Clear the erroneous "residue" */
+ STp->write_prot = 0;
+ STp->block_size = 0;
+ STp->ps[0].drv_file = STp->ps[0].drv_block = (-1);
+ STp->partition = STp->new_partition = 0;
+ STp->door_locked = ST_UNLOCKED;
+ return CHKRES_NOT_READY;
+ }
+ }
+
+ if (STp->omit_blklims)
+ STp->min_block = STp->max_block = (-1);
+ else {
+ memset((void *) &cmd[0], 0, MAX_COMMAND_SIZE);
+ cmd[0] = READ_BLOCK_LIMITS;
+
+ SRpnt = st_do_scsi(SRpnt, STp, cmd, 6, DMA_FROM_DEVICE,
+ STp->device->request_queue->rq_timeout,
+ MAX_READY_RETRIES, 1);
+ if (!SRpnt) {
+ retval = (STp->buffer)->syscall_result;
+ goto err_out;
+ }
+
+ if (!SRpnt->result && !STp->buffer->cmdstat.have_sense) {
+ STp->max_block = ((STp->buffer)->b_data[1] << 16) |
+ ((STp->buffer)->b_data[2] << 8) | (STp->buffer)->b_data[3];
+ STp->min_block = ((STp->buffer)->b_data[4] << 8) |
+ (STp->buffer)->b_data[5];
+ if ( DEB( debugging || ) !STp->inited)
+ st_printk(KERN_INFO, STp,
+ "Block limits %d - %d bytes.\n",
+ STp->min_block, STp->max_block);
+ } else {
+ STp->min_block = STp->max_block = (-1);
+ DEBC_printk(STp, "Can't read block limits.\n");
+ }
+ }
+
+ memset((void *) &cmd[0], 0, MAX_COMMAND_SIZE);
+ cmd[0] = MODE_SENSE;
+ cmd[4] = 12;
+
+ SRpnt = st_do_scsi(SRpnt, STp, cmd, 12, DMA_FROM_DEVICE,
+ STp->device->request_queue->rq_timeout,
+ MAX_READY_RETRIES, 1);
+ if (!SRpnt) {
+ retval = (STp->buffer)->syscall_result;
+ goto err_out;
+ }
+
+ if ((STp->buffer)->syscall_result != 0) {
+ DEBC_printk(STp, "No Mode Sense.\n");
+ STp->block_size = ST_DEFAULT_BLOCK; /* Educated guess (?) */
+ (STp->buffer)->syscall_result = 0; /* Prevent error propagation */
+ STp->drv_write_prot = 0;
+ } else {
+ DEBC_printk(STp,"Mode sense. Length %d, "
+ "medium %x, WBS %x, BLL %d\n",
+ (STp->buffer)->b_data[0],
+ (STp->buffer)->b_data[1],
+ (STp->buffer)->b_data[2],
+ (STp->buffer)->b_data[3]);
+
+ if ((STp->buffer)->b_data[3] >= 8) {
+ STp->drv_buffer = ((STp->buffer)->b_data[2] >> 4) & 7;
+ STp->density = (STp->buffer)->b_data[4];
+ STp->block_size = (STp->buffer)->b_data[9] * 65536 +
+ (STp->buffer)->b_data[10] * 256 + (STp->buffer)->b_data[11];
+ DEBC_printk(STp, "Density %x, tape length: %x, "
+ "drv buffer: %d\n",
+ STp->density,
+ (STp->buffer)->b_data[5] * 65536 +
+ (STp->buffer)->b_data[6] * 256 +
+ (STp->buffer)->b_data[7],
+ STp->drv_buffer);
+ }
+ STp->drv_write_prot = ((STp->buffer)->b_data[2] & 0x80) != 0;
+ if (!STp->drv_buffer && STp->immediate_filemark) {
+ st_printk(KERN_WARNING, STp,
+ "non-buffered tape: disabling "
+ "writing immediate filemarks\n");
+ STp->immediate_filemark = 0;
+ }
+ }
+ st_release_request(SRpnt);
+ SRpnt = NULL;
+ STp->inited = 1;
+
+ if (STp->block_size > 0)
+ (STp->buffer)->buffer_blocks =
+ (STp->buffer)->buffer_size / STp->block_size;
+ else
+ (STp->buffer)->buffer_blocks = 1;
+ (STp->buffer)->buffer_bytes = (STp->buffer)->read_pointer = 0;
+
+ DEBC_printk(STp, "Block size: %d, buffer size: %d (%d blocks).\n",
+ STp->block_size, (STp->buffer)->buffer_size,
+ (STp->buffer)->buffer_blocks);
+
+ if (STp->drv_write_prot) {
+ STp->write_prot = 1;
+
+ DEBC_printk(STp, "Write protected\n");
+
+ if (do_wait &&
+ ((st_flags & O_ACCMODE) == O_WRONLY ||
+ (st_flags & O_ACCMODE) == O_RDWR)) {
+ retval = (-EROFS);
+ goto err_out;
+ }
+ }
+
+ if (STp->can_partitions && STp->nbr_partitions < 1) {
+ /* This code is reached when the device is opened for the first time
+ after the driver has been initialized with tape in the drive and the
+ partition support has been enabled. */
+ DEBC_printk(STp, "Updating partition number in status.\n");
+ if ((STp->partition = find_partition(STp)) < 0) {
+ retval = STp->partition;
+ goto err_out;
+ }
+ STp->new_partition = STp->partition;
+ STp->nbr_partitions = 1; /* This guess will be updated when necessary */
+ }
+
+ if (new_session) { /* Change the drive parameters for the new mode */
+ STp->density_changed = STp->blksize_changed = 0;
+ STp->compression_changed = 0;
+ if (!(STm->defaults_for_writes) &&
+ (retval = set_mode_densblk(STp, STm)) < 0)
+ goto err_out;
+
+ if (STp->default_drvbuffer != 0xff) {
+ if (st_int_ioctl(STp, MTSETDRVBUFFER, STp->default_drvbuffer))
+ st_printk(KERN_WARNING, STp,
+ "Can't set default drive "
+ "buffering to %d.\n",
+ STp->default_drvbuffer);
+ }
+ }
+
+ return CHKRES_READY;
+
+ err_out:
+ return retval;
+}
+
+
+ /* Open the device. Needs to take the BKL only because of incrementing the SCSI host
+ module count. */
+static int st_open(struct inode *inode, struct file *filp)
+{
+ int i, retval = (-EIO);
+ int resumed = 0;
+ struct scsi_tape *STp;
+ struct st_partstat *STps;
+ int dev = TAPE_NR(inode);
+
+ /*
+ * We really want to do nonseekable_open(inode, filp); here, but some
+ * versions of tar incorrectly call lseek on tapes and bail out if that
+ * fails. So we disallow pread() and pwrite(), but permit lseeks.
+ */
+ filp->f_mode &= ~(FMODE_PREAD | FMODE_PWRITE);
+
+ if (!(STp = scsi_tape_get(dev))) {
+ return -ENXIO;
+ }
+
+ filp->private_data = STp;
+
+ spin_lock(&st_use_lock);
+ if (STp->in_use) {
+ spin_unlock(&st_use_lock);
+ DEBC_printk(STp, "Device already in use.\n");
+ scsi_tape_put(STp);
+ return (-EBUSY);
+ }
+
+ STp->in_use = 1;
+ spin_unlock(&st_use_lock);
+ STp->rew_at_close = STp->autorew_dev = (iminor(inode) & 0x80) == 0;
+
+ if (scsi_autopm_get_device(STp->device) < 0) {
+ retval = -EIO;
+ goto err_out;
+ }
+ resumed = 1;
+ if (!scsi_block_when_processing_errors(STp->device)) {
+ retval = (-ENXIO);
+ goto err_out;
+ }
+
+ /* See that we have at least a one page buffer available */
+ if (!enlarge_buffer(STp->buffer, PAGE_SIZE)) {
+ st_printk(KERN_WARNING, STp,
+ "Can't allocate one page tape buffer.\n");
+ retval = (-EOVERFLOW);
+ goto err_out;
+ }
+
+ (STp->buffer)->cleared = 0;
+ (STp->buffer)->writing = 0;
+ (STp->buffer)->syscall_result = 0;
+
+ STp->write_prot = ((filp->f_flags & O_ACCMODE) == O_RDONLY);
+
+ STp->dirty = 0;
+ for (i = 0; i < ST_NBR_PARTITIONS; i++) {
+ STps = &(STp->ps[i]);
+ STps->rw = ST_IDLE;
+ }
+ STp->try_dio_now = STp->try_dio;
+ STp->recover_count = 0;
+ DEB( STp->nbr_waits = STp->nbr_finished = 0;
+ STp->nbr_requests = STp->nbr_dio = STp->nbr_pages = 0; )
+
+ retval = check_tape(STp, filp);
+ if (retval < 0)
+ goto err_out;
+ if ((filp->f_flags & O_NONBLOCK) == 0 &&
+ retval != CHKRES_READY) {
+ if (STp->ready == NO_TAPE)
+ retval = (-ENOMEDIUM);
+ else
+ retval = (-EIO);
+ goto err_out;
+ }
+ return 0;
+
+ err_out:
+ normalize_buffer(STp->buffer);
+ spin_lock(&st_use_lock);
+ STp->in_use = 0;
+ spin_unlock(&st_use_lock);
+ if (resumed)
+ scsi_autopm_put_device(STp->device);
+ scsi_tape_put(STp);
+ return retval;
+
+}
+
+
+/* Flush the tape buffer before close */
+static int st_flush(struct file *filp, fl_owner_t id)
+{
+ int result = 0, result2;
+ unsigned char cmd[MAX_COMMAND_SIZE];
+ struct st_request *SRpnt;
+ struct scsi_tape *STp = filp->private_data;
+ struct st_modedef *STm = &(STp->modes[STp->current_mode]);
+ struct st_partstat *STps = &(STp->ps[STp->partition]);
+
+ if (file_count(filp) > 1)
+ return 0;
+
+ if (STps->rw == ST_WRITING && !STp->pos_unknown) {
+ result = st_flush_write_buffer(STp);
+ if (result != 0 && result != (-ENOSPC))
+ goto out;
+ }
+
+ if (STp->can_partitions &&
+ (result2 = switch_partition(STp)) < 0) {
+ DEBC_printk(STp, "switch_partition at close failed.\n");
+ if (result == 0)
+ result = result2;
+ goto out;
+ }
+
+ DEBC( if (STp->nbr_requests)
+ st_printk(KERN_DEBUG, STp,
+ "Number of r/w requests %d, dio used in %d, "
+ "pages %d.\n", STp->nbr_requests, STp->nbr_dio,
+ STp->nbr_pages));
+
+ if (STps->rw == ST_WRITING && !STp->pos_unknown) {
+ struct st_cmdstatus *cmdstatp = &STp->buffer->cmdstat;
+
+#if DEBUG
+ DEBC_printk(STp, "Async write waits %d, finished %d.\n",
+ STp->nbr_waits, STp->nbr_finished);
+#endif
+ memset(cmd, 0, MAX_COMMAND_SIZE);
+ cmd[0] = WRITE_FILEMARKS;
+ if (STp->immediate_filemark)
+ cmd[1] = 1;
+ cmd[4] = 1 + STp->two_fm;
+
+ SRpnt = st_do_scsi(NULL, STp, cmd, 0, DMA_NONE,
+ STp->device->request_queue->rq_timeout,
+ MAX_WRITE_RETRIES, 1);
+ if (!SRpnt) {
+ result = (STp->buffer)->syscall_result;
+ goto out;
+ }
+
+ if (STp->buffer->syscall_result == 0 ||
+ (cmdstatp->have_sense && !cmdstatp->deferred &&
+ (cmdstatp->flags & SENSE_EOM) &&
+ (cmdstatp->sense_hdr.sense_key == NO_SENSE ||
+ cmdstatp->sense_hdr.sense_key == RECOVERED_ERROR) &&
+ (!cmdstatp->remainder_valid || cmdstatp->uremainder64 == 0))) {
+ /* Write successful at EOM */
+ st_release_request(SRpnt);
+ SRpnt = NULL;
+ if (STps->drv_file >= 0)
+ STps->drv_file++;
+ STps->drv_block = 0;
+ if (STp->two_fm)
+ cross_eof(STp, 0);
+ STps->eof = ST_FM;
+ }
+ else { /* Write error */
+ st_release_request(SRpnt);
+ SRpnt = NULL;
+ st_printk(KERN_ERR, STp,
+ "Error on write filemark.\n");
+ if (result == 0)
+ result = (-EIO);
+ }
+
+ DEBC_printk(STp, "Buffer flushed, %d EOF(s) written\n", cmd[4]);
+ } else if (!STp->rew_at_close) {
+ STps = &(STp->ps[STp->partition]);
+ if (!STm->sysv || STps->rw != ST_READING) {
+ if (STp->can_bsr)
+ result = flush_buffer(STp, 0);
+ else if (STps->eof == ST_FM_HIT) {
+ result = cross_eof(STp, 0);
+ if (result) {
+ if (STps->drv_file >= 0)
+ STps->drv_file++;
+ STps->drv_block = 0;
+ STps->eof = ST_FM;
+ } else
+ STps->eof = ST_NOEOF;
+ }
+ } else if ((STps->eof == ST_NOEOF &&
+ !(result = cross_eof(STp, 1))) ||
+ STps->eof == ST_FM_HIT) {
+ if (STps->drv_file >= 0)
+ STps->drv_file++;
+ STps->drv_block = 0;
+ STps->eof = ST_FM;
+ }
+ }
+
+ out:
+ if (STp->rew_at_close) {
+ result2 = st_int_ioctl(STp, MTREW, 1);
+ if (result == 0)
+ result = result2;
+ }
+ return result;
+}
+
+
+/* Close the device and release it. BKL is not needed: this is the only thread
+ accessing this tape. */
+static int st_release(struct inode *inode, struct file *filp)
+{
+ struct scsi_tape *STp = filp->private_data;
+
+ if (STp->door_locked == ST_LOCKED_AUTO)
+ do_door_lock(STp, 0);
+
+ normalize_buffer(STp->buffer);
+ spin_lock(&st_use_lock);
+ STp->in_use = 0;
+ spin_unlock(&st_use_lock);
+ scsi_autopm_put_device(STp->device);
+ scsi_tape_put(STp);
+
+ return 0;
+}
+
+/* The checks common to both reading and writing */
+static ssize_t rw_checks(struct scsi_tape *STp, struct file *filp, size_t count)
+{
+ ssize_t retval = 0;
+
+ /*
+ * If we are in the middle of error recovery, don't let anyone
+ * else try and use this device. Also, if error recovery fails, it
+ * may try and take the device offline, in which case all further
+ * access to the device is prohibited.
+ */
+ if (!scsi_block_when_processing_errors(STp->device)) {
+ retval = (-ENXIO);
+ goto out;
+ }
+
+ if (STp->ready != ST_READY) {
+ if (STp->ready == ST_NO_TAPE)
+ retval = (-ENOMEDIUM);
+ else
+ retval = (-EIO);
+ goto out;
+ }
+
+ if (! STp->modes[STp->current_mode].defined) {
+ retval = (-ENXIO);
+ goto out;
+ }
+
+
+ /*
+ * If there was a bus reset, block further access
+ * to this device.
+ */
+ if (STp->pos_unknown) {
+ retval = (-EIO);
+ goto out;
+ }
+
+ if (count == 0)
+ goto out;
+
+ DEB(
+ if (!STp->in_use) {
+ st_printk(ST_DEB_MSG, STp,
+ "Incorrect device.\n");
+ retval = (-EIO);
+ goto out;
+ } ) /* end DEB */
+
+ if (STp->can_partitions &&
+ (retval = switch_partition(STp)) < 0)
+ goto out;
+
+ if (STp->block_size == 0 && STp->max_block > 0 &&
+ (count < STp->min_block || count > STp->max_block)) {
+ retval = (-EINVAL);
+ goto out;
+ }
+
+ if (STp->do_auto_lock && STp->door_locked == ST_UNLOCKED &&
+ !do_door_lock(STp, 1))
+ STp->door_locked = ST_LOCKED_AUTO;
+
+ out:
+ return retval;
+}
+
+
+static int setup_buffering(struct scsi_tape *STp, const char __user *buf,
+ size_t count, int is_read)
+{
+ int i, bufsize, retval = 0;
+ struct st_buffer *STbp = STp->buffer;
+
+ if (is_read)
+ i = STp->try_dio_now && try_rdio;
+ else
+ i = STp->try_dio_now && try_wdio;
+
+ if (i && ((unsigned long)buf & queue_dma_alignment(
+ STp->device->request_queue)) == 0) {
+ i = sgl_map_user_pages(STbp, STbp->use_sg, (unsigned long)buf,
+ count, (is_read ? READ : WRITE));
+ if (i > 0) {
+ STbp->do_dio = i;
+ STbp->buffer_bytes = 0; /* can be used as transfer counter */
+ }
+ else
+ STbp->do_dio = 0; /* fall back to buffering with any error */
+ STbp->sg_segs = STbp->do_dio;
+ DEB(
+ if (STbp->do_dio) {
+ STp->nbr_dio++;
+ STp->nbr_pages += STbp->do_dio;
+ }
+ )
+ } else
+ STbp->do_dio = 0;
+ DEB( STp->nbr_requests++; )
+
+ if (!STbp->do_dio) {
+ if (STp->block_size)
+ bufsize = STp->block_size > st_fixed_buffer_size ?
+ STp->block_size : st_fixed_buffer_size;
+ else {
+ bufsize = count;
+ /* Make sure that data from previous user is not leaked even if
+ HBA does not return correct residual */
+ if (is_read && STp->sili && !STbp->cleared)
+ clear_buffer(STbp);
+ }
+
+ if (bufsize > STbp->buffer_size &&
+ !enlarge_buffer(STbp, bufsize)) {
+ st_printk(KERN_WARNING, STp,
+ "Can't allocate %d byte tape buffer.\n",
+ bufsize);
+ retval = (-EOVERFLOW);
+ goto out;
+ }
+ if (STp->block_size)
+ STbp->buffer_blocks = bufsize / STp->block_size;
+ }
+
+ out:
+ return retval;
+}
+
+
+/* Can be called more than once after each setup_buffer() */
+static void release_buffering(struct scsi_tape *STp, int is_read)
+{
+ struct st_buffer *STbp;
+
+ STbp = STp->buffer;
+ if (STbp->do_dio) {
+ sgl_unmap_user_pages(STbp, STbp->do_dio, is_read);
+ STbp->do_dio = 0;
+ STbp->sg_segs = 0;
+ }
+}
+
+
+/* Write command */
+static ssize_t
+st_write(struct file *filp, const char __user *buf, size_t count, loff_t * ppos)
+{
+ ssize_t total;
+ ssize_t i, do_count, blks, transfer;
+ ssize_t retval;
+ int undone, retry_eot = 0, scode;
+ int async_write;
+ unsigned char cmd[MAX_COMMAND_SIZE];
+ const char __user *b_point;
+ struct st_request *SRpnt = NULL;
+ struct scsi_tape *STp = filp->private_data;
+ struct st_modedef *STm;
+ struct st_partstat *STps;
+ struct st_buffer *STbp;
+
+ if (mutex_lock_interruptible(&STp->lock))
+ return -ERESTARTSYS;
+
+ retval = rw_checks(STp, filp, count);
+ if (retval || count == 0)
+ goto out;
+
+ /* Write must be integral number of blocks */
+ if (STp->block_size != 0 && (count % STp->block_size) != 0) {
+ st_printk(KERN_WARNING, STp,
+ "Write not multiple of tape block size.\n");
+ retval = (-EINVAL);
+ goto out;
+ }
+
+ STm = &(STp->modes[STp->current_mode]);
+ STps = &(STp->ps[STp->partition]);
+
+ if (STp->write_prot) {
+ retval = (-EACCES);
+ goto out;
+ }
+
+
+ if (STps->rw == ST_READING) {
+ retval = flush_buffer(STp, 0);
+ if (retval)
+ goto out;
+ STps->rw = ST_WRITING;
+ } else if (STps->rw != ST_WRITING &&
+ STps->drv_file == 0 && STps->drv_block == 0) {
+ if ((retval = set_mode_densblk(STp, STm)) < 0)
+ goto out;
+ if (STm->default_compression != ST_DONT_TOUCH &&
+ !(STp->compression_changed)) {
+ if (st_compression(STp, (STm->default_compression == ST_YES))) {
+ st_printk(KERN_WARNING, STp,
+ "Can't set default compression.\n");
+ if (modes_defined) {
+ retval = (-EINVAL);
+ goto out;
+ }
+ }
+ }
+ }
+
+ STbp = STp->buffer;
+ i = write_behind_check(STp);
+ if (i) {
+ if (i == -ENOSPC)
+ STps->eof = ST_EOM_OK;
+ else
+ STps->eof = ST_EOM_ERROR;
+ }
+
+ if (STps->eof == ST_EOM_OK) {
+ STps->eof = ST_EOD_1; /* allow next write */
+ retval = (-ENOSPC);
+ goto out;
+ }
+ else if (STps->eof == ST_EOM_ERROR) {
+ retval = (-EIO);
+ goto out;
+ }
+
+ /* Check the buffer readability in cases where copy_user might catch
+ the problems after some tape movement. */
+ if (STp->block_size != 0 &&
+ !STbp->do_dio &&
+ (copy_from_user(&i, buf, 1) != 0 ||
+ copy_from_user(&i, buf + count - 1, 1) != 0)) {
+ retval = (-EFAULT);
+ goto out;
+ }
+
+ retval = setup_buffering(STp, buf, count, 0);
+ if (retval)
+ goto out;
+
+ total = count;
+
+ memset(cmd, 0, MAX_COMMAND_SIZE);
+ cmd[0] = WRITE_6;
+ cmd[1] = (STp->block_size != 0);
+
+ STps->rw = ST_WRITING;
+
+ b_point = buf;
+ while (count > 0 && !retry_eot) {
+
+ if (STbp->do_dio) {
+ do_count = count;
+ }
+ else {
+ if (STp->block_size == 0)
+ do_count = count;
+ else {
+ do_count = STbp->buffer_blocks * STp->block_size -
+ STbp->buffer_bytes;
+ if (do_count > count)
+ do_count = count;
+ }
+
+ i = append_to_buffer(b_point, STbp, do_count);
+ if (i) {
+ retval = i;
+ goto out;
+ }
+ }
+ count -= do_count;
+ b_point += do_count;
+
+ async_write = STp->block_size == 0 && !STbp->do_dio &&
+ STm->do_async_writes && STps->eof < ST_EOM_OK;
+
+ if (STp->block_size != 0 && STm->do_buffer_writes &&
+ !(STp->try_dio_now && try_wdio) && STps->eof < ST_EOM_OK &&
+ STbp->buffer_bytes < STbp->buffer_size) {
+ STp->dirty = 1;
+ /* Don't write a buffer that is not full enough. */
+ if (!async_write && count == 0)
+ break;
+ }
+
+ retry_write:
+ if (STp->block_size == 0)
+ blks = transfer = do_count;
+ else {
+ if (!STbp->do_dio)
+ blks = STbp->buffer_bytes;
+ else
+ blks = do_count;
+ blks /= STp->block_size;
+ transfer = blks * STp->block_size;
+ }
+ cmd[2] = blks >> 16;
+ cmd[3] = blks >> 8;
+ cmd[4] = blks;
+
+ SRpnt = st_do_scsi(SRpnt, STp, cmd, transfer, DMA_TO_DEVICE,
+ STp->device->request_queue->rq_timeout,
+ MAX_WRITE_RETRIES, !async_write);
+ if (!SRpnt) {
+ retval = STbp->syscall_result;
+ goto out;
+ }
+ if (async_write && !STbp->syscall_result) {
+ STbp->writing = transfer;
+ STp->dirty = !(STbp->writing ==
+ STbp->buffer_bytes);
+ SRpnt = NULL; /* Prevent releasing this request! */
+ DEB( STp->write_pending = 1; )
+ break;
+ }
+
+ if (STbp->syscall_result != 0) {
+ struct st_cmdstatus *cmdstatp = &STp->buffer->cmdstat;
+
+ DEBC_printk(STp, "Error on write:\n");
+ if (cmdstatp->have_sense && (cmdstatp->flags & SENSE_EOM)) {
+ scode = cmdstatp->sense_hdr.sense_key;
+ if (cmdstatp->remainder_valid)
+ undone = (int)cmdstatp->uremainder64;
+ else if (STp->block_size == 0 &&
+ scode == VOLUME_OVERFLOW)
+ undone = transfer;
+ else
+ undone = 0;
+ if (STp->block_size != 0)
+ undone *= STp->block_size;
+ if (undone <= do_count) {
+ /* Only data from this write is not written */
+ count += undone;
+ b_point -= undone;
+ do_count -= undone;
+ if (STp->block_size)
+ blks = (transfer - undone) / STp->block_size;
+ STps->eof = ST_EOM_OK;
+ /* Continue in fixed block mode if all written
+ in this request but still something left to write
+ (retval left to zero)
+ */
+ if (STp->block_size == 0 ||
+ undone > 0 || count == 0)
+ retval = (-ENOSPC); /* EOM within current request */
+ DEBC_printk(STp, "EOM with %d "
+ "bytes unwritten.\n",
+ (int)count);
+ } else {
+ /* EOT within data buffered earlier (possible only
+ in fixed block mode without direct i/o) */
+ if (!retry_eot && !cmdstatp->deferred &&
+ (scode == NO_SENSE || scode == RECOVERED_ERROR)) {
+ move_buffer_data(STp->buffer, transfer - undone);
+ retry_eot = 1;
+ if (STps->drv_block >= 0) {
+ STps->drv_block += (transfer - undone) /
+ STp->block_size;
+ }
+ STps->eof = ST_EOM_OK;
+ DEBC_printk(STp, "Retry "
+ "write of %d "
+ "bytes at EOM.\n",
+ STp->buffer->buffer_bytes);
+ goto retry_write;
+ }
+ else {
+ /* Either error within data buffered by driver or
+ failed retry */
+ count -= do_count;
+ blks = do_count = 0;
+ STps->eof = ST_EOM_ERROR;
+ STps->drv_block = (-1); /* Too cautious? */
+ retval = (-EIO); /* EOM for old data */
+ DEBC_printk(STp, "EOM with "
+ "lost data.\n");
+ }
+ }
+ } else {
+ count += do_count;
+ STps->drv_block = (-1); /* Too cautious? */
+ retval = STbp->syscall_result;
+ }
+
+ }
+
+ if (STps->drv_block >= 0) {
+ if (STp->block_size == 0)
+ STps->drv_block += (do_count > 0);
+ else
+ STps->drv_block += blks;
+ }
+
+ STbp->buffer_bytes = 0;
+ STp->dirty = 0;
+
+ if (retval || retry_eot) {
+ if (count < total)
+ retval = total - count;
+ goto out;
+ }
+ }
+
+ if (STps->eof == ST_EOD_1)
+ STps->eof = ST_EOM_OK;
+ else if (STps->eof != ST_EOM_OK)
+ STps->eof = ST_NOEOF;
+ retval = total - count;
+
+ out:
+ if (SRpnt != NULL)
+ st_release_request(SRpnt);
+ release_buffering(STp, 0);
+ mutex_unlock(&STp->lock);
+
+ return retval;
+}
+
+/* Read data from the tape. Returns zero in the normal case, one if the
+ eof status has changed, and the negative error code in case of a
+ fatal error. Otherwise updates the buffer and the eof state.
+
+ Does release user buffer mapping if it is set.
+*/
+static long read_tape(struct scsi_tape *STp, long count,
+ struct st_request ** aSRpnt)
+{
+ int transfer, blks, bytes;
+ unsigned char cmd[MAX_COMMAND_SIZE];
+ struct st_request *SRpnt;
+ struct st_modedef *STm;
+ struct st_partstat *STps;
+ struct st_buffer *STbp;
+ int retval = 0;
+
+ if (count == 0)
+ return 0;
+
+ STm = &(STp->modes[STp->current_mode]);
+ STps = &(STp->ps[STp->partition]);
+ if (STps->eof == ST_FM_HIT)
+ return 1;
+ STbp = STp->buffer;
+
+ if (STp->block_size == 0)
+ blks = bytes = count;
+ else {
+ if (!(STp->try_dio_now && try_rdio) && STm->do_read_ahead) {
+ blks = (STp->buffer)->buffer_blocks;
+ bytes = blks * STp->block_size;
+ } else {
+ bytes = count;
+ if (!STbp->do_dio && bytes > (STp->buffer)->buffer_size)
+ bytes = (STp->buffer)->buffer_size;
+ blks = bytes / STp->block_size;
+ bytes = blks * STp->block_size;
+ }
+ }
+
+ memset(cmd, 0, MAX_COMMAND_SIZE);
+ cmd[0] = READ_6;
+ cmd[1] = (STp->block_size != 0);
+ if (!cmd[1] && STp->sili)
+ cmd[1] |= 2;
+ cmd[2] = blks >> 16;
+ cmd[3] = blks >> 8;
+ cmd[4] = blks;
+
+ SRpnt = *aSRpnt;
+ SRpnt = st_do_scsi(SRpnt, STp, cmd, bytes, DMA_FROM_DEVICE,
+ STp->device->request_queue->rq_timeout,
+ MAX_RETRIES, 1);
+ release_buffering(STp, 1);
+ *aSRpnt = SRpnt;
+ if (!SRpnt)
+ return STbp->syscall_result;
+
+ STbp->read_pointer = 0;
+ STps->at_sm = 0;
+
+ /* Something to check */
+ if (STbp->syscall_result) {
+ struct st_cmdstatus *cmdstatp = &STp->buffer->cmdstat;
+
+ retval = 1;
+ DEBC_printk(STp,
+ "Sense: %2x %2x %2x %2x %2x %2x %2x %2x\n",
+ SRpnt->sense[0], SRpnt->sense[1],
+ SRpnt->sense[2], SRpnt->sense[3],
+ SRpnt->sense[4], SRpnt->sense[5],
+ SRpnt->sense[6], SRpnt->sense[7]);
+ if (cmdstatp->have_sense) {
+
+ if (cmdstatp->sense_hdr.sense_key == BLANK_CHECK)
+ cmdstatp->flags &= 0xcf; /* No need for EOM in this case */
+
+ if (cmdstatp->flags != 0) { /* EOF, EOM, or ILI */
+ /* Compute the residual count */
+ if (cmdstatp->remainder_valid)
+ transfer = (int)cmdstatp->uremainder64;
+ else
+ transfer = 0;
+ if (cmdstatp->sense_hdr.sense_key == MEDIUM_ERROR) {
+ if (STp->block_size == 0)
+ transfer = bytes;
+ /* Some drives set ILI with MEDIUM ERROR */
+ cmdstatp->flags &= ~SENSE_ILI;
+ }
+
+ if (cmdstatp->flags & SENSE_ILI) { /* ILI */
+ if (STp->block_size == 0 &&
+ transfer < 0) {
+ st_printk(KERN_NOTICE, STp,
+ "Failed to read %d "
+ "byte block with %d "
+ "byte transfer.\n",
+ bytes - transfer,
+ bytes);
+ if (STps->drv_block >= 0)
+ STps->drv_block += 1;
+ STbp->buffer_bytes = 0;
+ return (-ENOMEM);
+ } else if (STp->block_size == 0) {
+ STbp->buffer_bytes = bytes - transfer;
+ } else {
+ st_release_request(SRpnt);
+ SRpnt = *aSRpnt = NULL;
+ if (transfer == blks) { /* We did not get anything, error */
+ st_printk(KERN_NOTICE, STp,
+ "Incorrect "
+ "block size.\n");
+ if (STps->drv_block >= 0)
+ STps->drv_block += blks - transfer + 1;
+ st_int_ioctl(STp, MTBSR, 1);
+ return (-EIO);
+ }
+ /* We have some data, deliver it */
+ STbp->buffer_bytes = (blks - transfer) *
+ STp->block_size;
+ DEBC_printk(STp, "ILI but "
+ "enough data "
+ "received %ld "
+ "%d.\n", count,
+ STbp->buffer_bytes);
+ if (STps->drv_block >= 0)
+ STps->drv_block += 1;
+ if (st_int_ioctl(STp, MTBSR, 1))
+ return (-EIO);
+ }
+ } else if (cmdstatp->flags & SENSE_FMK) { /* FM overrides EOM */
+ if (STps->eof != ST_FM_HIT)
+ STps->eof = ST_FM_HIT;
+ else
+ STps->eof = ST_EOD_2;
+ if (STp->block_size == 0)
+ STbp->buffer_bytes = 0;
+ else
+ STbp->buffer_bytes =
+ bytes - transfer * STp->block_size;
+ DEBC_printk(STp, "EOF detected (%d "
+ "bytes read).\n",
+ STbp->buffer_bytes);
+ } else if (cmdstatp->flags & SENSE_EOM) {
+ if (STps->eof == ST_FM)
+ STps->eof = ST_EOD_1;
+ else
+ STps->eof = ST_EOM_OK;
+ if (STp->block_size == 0)
+ STbp->buffer_bytes = bytes - transfer;
+ else
+ STbp->buffer_bytes =
+ bytes - transfer * STp->block_size;
+
+ DEBC_printk(STp, "EOM detected (%d "
+ "bytes read).\n",
+ STbp->buffer_bytes);
+ }
+ }
+ /* end of EOF, EOM, ILI test */
+ else { /* nonzero sense key */
+ DEBC_printk(STp, "Tape error while reading.\n");
+ STps->drv_block = (-1);
+ if (STps->eof == ST_FM &&
+ cmdstatp->sense_hdr.sense_key == BLANK_CHECK) {
+ DEBC_printk(STp, "Zero returned for "
+ "first BLANK CHECK "
+ "after EOF.\n");
+ STps->eof = ST_EOD_2; /* First BLANK_CHECK after FM */
+ } else /* Some other extended sense code */
+ retval = (-EIO);
+ }
+
+ if (STbp->buffer_bytes < 0) /* Caused by bogus sense data */
+ STbp->buffer_bytes = 0;
+ }
+ /* End of extended sense test */
+ else { /* Non-extended sense */
+ retval = STbp->syscall_result;
+ }
+
+ }
+ /* End of error handling */
+ else { /* Read successful */
+ STbp->buffer_bytes = bytes;
+ if (STp->sili) /* In fixed block mode residual is always zero here */
+ STbp->buffer_bytes -= STp->buffer->cmdstat.residual;
+ }
+
+ if (STps->drv_block >= 0) {
+ if (STp->block_size == 0)
+ STps->drv_block++;
+ else
+ STps->drv_block += STbp->buffer_bytes / STp->block_size;
+ }
+ return retval;
+}
+
+
+/* Read command */
+static ssize_t
+st_read(struct file *filp, char __user *buf, size_t count, loff_t * ppos)
+{
+ ssize_t total;
+ ssize_t retval = 0;
+ ssize_t i, transfer;
+ int special, do_dio = 0;
+ struct st_request *SRpnt = NULL;
+ struct scsi_tape *STp = filp->private_data;
+ struct st_modedef *STm;
+ struct st_partstat *STps;
+ struct st_buffer *STbp = STp->buffer;
+
+ if (mutex_lock_interruptible(&STp->lock))
+ return -ERESTARTSYS;
+
+ retval = rw_checks(STp, filp, count);
+ if (retval || count == 0)
+ goto out;
+
+ STm = &(STp->modes[STp->current_mode]);
+ if (STp->block_size != 0 && (count % STp->block_size) != 0) {
+ if (!STm->do_read_ahead) {
+ retval = (-EINVAL); /* Read must be integral number of blocks */
+ goto out;
+ }
+ STp->try_dio_now = 0; /* Direct i/o can't handle split blocks */
+ }
+
+ STps = &(STp->ps[STp->partition]);
+ if (STps->rw == ST_WRITING) {
+ retval = flush_buffer(STp, 0);
+ if (retval)
+ goto out;
+ STps->rw = ST_READING;
+ }
+ DEB(
+ if (debugging && STps->eof != ST_NOEOF)
+ st_printk(ST_DEB_MSG, STp,
+ "EOF/EOM flag up (%d). Bytes %d\n",
+ STps->eof, STbp->buffer_bytes);
+ ) /* end DEB */
+
+ retval = setup_buffering(STp, buf, count, 1);
+ if (retval)
+ goto out;
+ do_dio = STbp->do_dio;
+
+ if (STbp->buffer_bytes == 0 &&
+ STps->eof >= ST_EOD_1) {
+ if (STps->eof < ST_EOD) {
+ STps->eof += 1;
+ retval = 0;
+ goto out;
+ }
+ retval = (-EIO); /* EOM or Blank Check */
+ goto out;
+ }
+
+ if (do_dio) {
+ /* Check the buffer writability before any tape movement. Don't alter
+ buffer data. */
+ if (copy_from_user(&i, buf, 1) != 0 ||
+ copy_to_user(buf, &i, 1) != 0 ||
+ copy_from_user(&i, buf + count - 1, 1) != 0 ||
+ copy_to_user(buf + count - 1, &i, 1) != 0) {
+ retval = (-EFAULT);
+ goto out;
+ }
+ }
+
+ STps->rw = ST_READING;
+
+
+ /* Loop until enough data in buffer or a special condition found */
+ for (total = 0, special = 0; total < count && !special;) {
+
+ /* Get new data if the buffer is empty */
+ if (STbp->buffer_bytes == 0) {
+ special = read_tape(STp, count - total, &SRpnt);
+ if (special < 0) { /* No need to continue read */
+ retval = special;
+ goto out;
+ }
+ }
+
+ /* Move the data from driver buffer to user buffer */
+ if (STbp->buffer_bytes > 0) {
+ DEB(
+ if (debugging && STps->eof != ST_NOEOF)
+ st_printk(ST_DEB_MSG, STp,
+ "EOF up (%d). Left %d, needed %d.\n",
+ STps->eof, STbp->buffer_bytes,
+ (int)(count - total));
+ ) /* end DEB */
+ transfer = STbp->buffer_bytes < count - total ?
+ STbp->buffer_bytes : count - total;
+ if (!do_dio) {
+ i = from_buffer(STbp, buf, transfer);
+ if (i) {
+ retval = i;
+ goto out;
+ }
+ }
+ buf += transfer;
+ total += transfer;
+ }
+
+ if (STp->block_size == 0)
+ break; /* Read only one variable length block */
+
+ } /* for (total = 0, special = 0;
+ total < count && !special; ) */
+
+ /* Change the eof state if no data from tape or buffer */
+ if (total == 0) {
+ if (STps->eof == ST_FM_HIT) {
+ STps->eof = ST_FM;
+ STps->drv_block = 0;
+ if (STps->drv_file >= 0)
+ STps->drv_file++;
+ } else if (STps->eof == ST_EOD_1) {
+ STps->eof = ST_EOD_2;
+ STps->drv_block = 0;
+ if (STps->drv_file >= 0)
+ STps->drv_file++;
+ } else if (STps->eof == ST_EOD_2)
+ STps->eof = ST_EOD;
+ } else if (STps->eof == ST_FM)
+ STps->eof = ST_NOEOF;
+ retval = total;
+
+ out:
+ if (SRpnt != NULL) {
+ st_release_request(SRpnt);
+ SRpnt = NULL;
+ }
+ if (do_dio) {
+ release_buffering(STp, 1);
+ STbp->buffer_bytes = 0;
+ }
+ mutex_unlock(&STp->lock);
+
+ return retval;
+}
+
+
+
+DEB(
+/* Set the driver options */
+static void st_log_options(struct scsi_tape * STp, struct st_modedef * STm)
+{
+ if (debugging) {
+ st_printk(KERN_INFO, STp,
+ "Mode %d options: buffer writes: %d, "
+ "async writes: %d, read ahead: %d\n",
+ STp->current_mode, STm->do_buffer_writes,
+ STm->do_async_writes, STm->do_read_ahead);
+ st_printk(KERN_INFO, STp,
+ " can bsr: %d, two FMs: %d, "
+ "fast mteom: %d, auto lock: %d,\n",
+ STp->can_bsr, STp->two_fm, STp->fast_mteom,
+ STp->do_auto_lock);
+ st_printk(KERN_INFO, STp,
+ " defs for wr: %d, no block limits: %d, "
+ "partitions: %d, s2 log: %d\n",
+ STm->defaults_for_writes, STp->omit_blklims,
+ STp->can_partitions, STp->scsi2_logical);
+ st_printk(KERN_INFO, STp,
+ " sysv: %d nowait: %d sili: %d "
+ "nowait_filemark: %d\n",
+ STm->sysv, STp->immediate, STp->sili,
+ STp->immediate_filemark);
+ st_printk(KERN_INFO, STp, " debugging: %d\n", debugging);
+ }
+}
+ )
+
+
+static int st_set_options(struct scsi_tape *STp, long options)
+{
+ int value;
+ long code;
+ struct st_modedef *STm;
+ struct cdev *cd0, *cd1;
+ struct device *d0, *d1;
+
+ STm = &(STp->modes[STp->current_mode]);
+ if (!STm->defined) {
+ cd0 = STm->cdevs[0];
+ cd1 = STm->cdevs[1];
+ d0 = STm->devs[0];
+ d1 = STm->devs[1];
+ memcpy(STm, &(STp->modes[0]), sizeof(struct st_modedef));
+ STm->cdevs[0] = cd0;
+ STm->cdevs[1] = cd1;
+ STm->devs[0] = d0;
+ STm->devs[1] = d1;
+ modes_defined = 1;
+ DEBC_printk(STp, "Initialized mode %d definition from mode 0\n",
+ STp->current_mode);
+ }
+
+ code = options & MT_ST_OPTIONS;
+ if (code == MT_ST_BOOLEANS) {
+ STm->do_buffer_writes = (options & MT_ST_BUFFER_WRITES) != 0;
+ STm->do_async_writes = (options & MT_ST_ASYNC_WRITES) != 0;
+ STm->defaults_for_writes = (options & MT_ST_DEF_WRITES) != 0;
+ STm->do_read_ahead = (options & MT_ST_READ_AHEAD) != 0;
+ STp->two_fm = (options & MT_ST_TWO_FM) != 0;
+ STp->fast_mteom = (options & MT_ST_FAST_MTEOM) != 0;
+ STp->do_auto_lock = (options & MT_ST_AUTO_LOCK) != 0;
+ STp->can_bsr = (options & MT_ST_CAN_BSR) != 0;
+ STp->omit_blklims = (options & MT_ST_NO_BLKLIMS) != 0;
+ if ((STp->device)->scsi_level >= SCSI_2)
+ STp->can_partitions = (options & MT_ST_CAN_PARTITIONS) != 0;
+ STp->scsi2_logical = (options & MT_ST_SCSI2LOGICAL) != 0;
+ STp->immediate = (options & MT_ST_NOWAIT) != 0;
+ STp->immediate_filemark = (options & MT_ST_NOWAIT_EOF) != 0;
+ STm->sysv = (options & MT_ST_SYSV) != 0;
+ STp->sili = (options & MT_ST_SILI) != 0;
+ DEB( debugging = (options & MT_ST_DEBUGGING) != 0;
+ st_log_options(STp, STm); )
+ } else if (code == MT_ST_SETBOOLEANS || code == MT_ST_CLEARBOOLEANS) {
+ value = (code == MT_ST_SETBOOLEANS);
+ if ((options & MT_ST_BUFFER_WRITES) != 0)
+ STm->do_buffer_writes = value;
+ if ((options & MT_ST_ASYNC_WRITES) != 0)
+ STm->do_async_writes = value;
+ if ((options & MT_ST_DEF_WRITES) != 0)
+ STm->defaults_for_writes = value;
+ if ((options & MT_ST_READ_AHEAD) != 0)
+ STm->do_read_ahead = value;
+ if ((options & MT_ST_TWO_FM) != 0)
+ STp->two_fm = value;
+ if ((options & MT_ST_FAST_MTEOM) != 0)
+ STp->fast_mteom = value;
+ if ((options & MT_ST_AUTO_LOCK) != 0)
+ STp->do_auto_lock = value;
+ if ((options & MT_ST_CAN_BSR) != 0)
+ STp->can_bsr = value;
+ if ((options & MT_ST_NO_BLKLIMS) != 0)
+ STp->omit_blklims = value;
+ if ((STp->device)->scsi_level >= SCSI_2 &&
+ (options & MT_ST_CAN_PARTITIONS) != 0)
+ STp->can_partitions = value;
+ if ((options & MT_ST_SCSI2LOGICAL) != 0)
+ STp->scsi2_logical = value;
+ if ((options & MT_ST_NOWAIT) != 0)
+ STp->immediate = value;
+ if ((options & MT_ST_NOWAIT_EOF) != 0)
+ STp->immediate_filemark = value;
+ if ((options & MT_ST_SYSV) != 0)
+ STm->sysv = value;
+ if ((options & MT_ST_SILI) != 0)
+ STp->sili = value;
+ DEB(
+ if ((options & MT_ST_DEBUGGING) != 0)
+ debugging = value;
+ st_log_options(STp, STm); )
+ } else if (code == MT_ST_WRITE_THRESHOLD) {
+ /* Retained for compatibility */
+ } else if (code == MT_ST_DEF_BLKSIZE) {
+ value = (options & ~MT_ST_OPTIONS);
+ if (value == ~MT_ST_OPTIONS) {
+ STm->default_blksize = (-1);
+ DEBC_printk(STp, "Default block size disabled.\n");
+ } else {
+ STm->default_blksize = value;
+ DEBC_printk(STp,"Default block size set to "
+ "%d bytes.\n", STm->default_blksize);
+ if (STp->ready == ST_READY) {
+ STp->blksize_changed = 0;
+ set_mode_densblk(STp, STm);
+ }
+ }
+ } else if (code == MT_ST_TIMEOUTS) {
+ value = (options & ~MT_ST_OPTIONS);
+ if ((value & MT_ST_SET_LONG_TIMEOUT) != 0) {
+ STp->long_timeout = (value & ~MT_ST_SET_LONG_TIMEOUT) * HZ;
+ DEBC_printk(STp, "Long timeout set to %d seconds.\n",
+ (value & ~MT_ST_SET_LONG_TIMEOUT));
+ } else {
+ blk_queue_rq_timeout(STp->device->request_queue,
+ value * HZ);
+ DEBC_printk(STp, "Normal timeout set to %d seconds.\n",
+ value);
+ }
+ } else if (code == MT_ST_SET_CLN) {
+ value = (options & ~MT_ST_OPTIONS) & 0xff;
+ if (value != 0 &&
+ (value < EXTENDED_SENSE_START ||
+ value >= SCSI_SENSE_BUFFERSIZE))
+ return (-EINVAL);
+ STp->cln_mode = value;
+ STp->cln_sense_mask = (options >> 8) & 0xff;
+ STp->cln_sense_value = (options >> 16) & 0xff;
+ st_printk(KERN_INFO, STp,
+ "Cleaning request mode %d, mask %02x, value %02x\n",
+ value, STp->cln_sense_mask, STp->cln_sense_value);
+ } else if (code == MT_ST_DEF_OPTIONS) {
+ code = (options & ~MT_ST_CLEAR_DEFAULT);
+ value = (options & MT_ST_CLEAR_DEFAULT);
+ if (code == MT_ST_DEF_DENSITY) {
+ if (value == MT_ST_CLEAR_DEFAULT) {
+ STm->default_density = (-1);
+ DEBC_printk(STp,
+ "Density default disabled.\n");
+ } else {
+ STm->default_density = value & 0xff;
+ DEBC_printk(STp, "Density default set to %x\n",
+ STm->default_density);
+ if (STp->ready == ST_READY) {
+ STp->density_changed = 0;
+ set_mode_densblk(STp, STm);
+ }
+ }
+ } else if (code == MT_ST_DEF_DRVBUFFER) {
+ if (value == MT_ST_CLEAR_DEFAULT) {
+ STp->default_drvbuffer = 0xff;
+ DEBC_printk(STp,
+ "Drive buffer default disabled.\n");
+ } else {
+ STp->default_drvbuffer = value & 7;
+ DEBC_printk(STp,
+ "Drive buffer default set to %x\n",
+ STp->default_drvbuffer);
+ if (STp->ready == ST_READY)
+ st_int_ioctl(STp, MTSETDRVBUFFER, STp->default_drvbuffer);
+ }
+ } else if (code == MT_ST_DEF_COMPRESSION) {
+ if (value == MT_ST_CLEAR_DEFAULT) {
+ STm->default_compression = ST_DONT_TOUCH;
+ DEBC_printk(STp,
+ "Compression default disabled.\n");
+ } else {
+ if ((value & 0xff00) != 0) {
+ STp->c_algo = (value & 0xff00) >> 8;
+ DEBC_printk(STp, "Compression "
+ "algorithm set to 0x%x.\n",
+ STp->c_algo);
+ }
+ if ((value & 0xff) != 0xff) {
+ STm->default_compression = (value & 1 ? ST_YES : ST_NO);
+ DEBC_printk(STp, "Compression default "
+ "set to %x\n",
+ (value & 1));
+ if (STp->ready == ST_READY) {
+ STp->compression_changed = 0;
+ st_compression(STp, (STm->default_compression == ST_YES));
+ }
+ }
+ }
+ }
+ } else
+ return (-EIO);
+
+ return 0;
+}
+
+#define MODE_HEADER_LENGTH 4
+
+/* Mode header and page byte offsets */
+#define MH_OFF_DATA_LENGTH 0
+#define MH_OFF_MEDIUM_TYPE 1
+#define MH_OFF_DEV_SPECIFIC 2
+#define MH_OFF_BDESCS_LENGTH 3
+#define MP_OFF_PAGE_NBR 0
+#define MP_OFF_PAGE_LENGTH 1
+
+/* Mode header and page bit masks */
+#define MH_BIT_WP 0x80
+#define MP_MSK_PAGE_NBR 0x3f
+
+/* Don't return block descriptors */
+#define MODE_SENSE_OMIT_BDESCS 0x08
+
+#define MODE_SELECT_PAGE_FORMAT 0x10
+
+/* Read a mode page into the tape buffer. The block descriptors are included
+ if incl_block_descs is true. The page control is ored to the page number
+ parameter, if necessary. */
+static int read_mode_page(struct scsi_tape *STp, int page, int omit_block_descs)
+{
+ unsigned char cmd[MAX_COMMAND_SIZE];
+ struct st_request *SRpnt;
+
+ memset(cmd, 0, MAX_COMMAND_SIZE);
+ cmd[0] = MODE_SENSE;
+ if (omit_block_descs)
+ cmd[1] = MODE_SENSE_OMIT_BDESCS;
+ cmd[2] = page;
+ cmd[4] = 255;
+
+ SRpnt = st_do_scsi(NULL, STp, cmd, cmd[4], DMA_FROM_DEVICE,
+ STp->device->request_queue->rq_timeout, 0, 1);
+ if (SRpnt == NULL)
+ return (STp->buffer)->syscall_result;
+
+ st_release_request(SRpnt);
+
+ return STp->buffer->syscall_result;
+}
+
+
+/* Send the mode page in the tape buffer to the drive. Assumes that the mode data
+ in the buffer is correctly formatted. The long timeout is used if slow is non-zero. */
+static int write_mode_page(struct scsi_tape *STp, int page, int slow)
+{
+ int pgo;
+ unsigned char cmd[MAX_COMMAND_SIZE];
+ struct st_request *SRpnt;
+ int timeout;
+
+ memset(cmd, 0, MAX_COMMAND_SIZE);
+ cmd[0] = MODE_SELECT;
+ cmd[1] = MODE_SELECT_PAGE_FORMAT;
+ pgo = MODE_HEADER_LENGTH + (STp->buffer)->b_data[MH_OFF_BDESCS_LENGTH];
+ cmd[4] = pgo + (STp->buffer)->b_data[pgo + MP_OFF_PAGE_LENGTH] + 2;
+
+ /* Clear reserved fields */
+ (STp->buffer)->b_data[MH_OFF_DATA_LENGTH] = 0;
+ (STp->buffer)->b_data[MH_OFF_MEDIUM_TYPE] = 0;
+ (STp->buffer)->b_data[MH_OFF_DEV_SPECIFIC] &= ~MH_BIT_WP;
+ (STp->buffer)->b_data[pgo + MP_OFF_PAGE_NBR] &= MP_MSK_PAGE_NBR;
+
+ timeout = slow ?
+ STp->long_timeout : STp->device->request_queue->rq_timeout;
+ SRpnt = st_do_scsi(NULL, STp, cmd, cmd[4], DMA_TO_DEVICE,
+ timeout, 0, 1);
+ if (SRpnt == NULL)
+ return (STp->buffer)->syscall_result;
+
+ st_release_request(SRpnt);
+
+ return STp->buffer->syscall_result;
+}
+
+
+#define COMPRESSION_PAGE 0x0f
+#define COMPRESSION_PAGE_LENGTH 16
+
+#define CP_OFF_DCE_DCC 2
+#define CP_OFF_C_ALGO 7
+
+#define DCE_MASK 0x80
+#define DCC_MASK 0x40
+#define RED_MASK 0x60
+
+
+/* Control the compression with mode page 15. Algorithm not changed if zero.
+
+ The block descriptors are read and written because Sony SDT-7000 does not
+ work without this (suggestion from Michael Schaefer <Michael.Schaefer@dlr.de>).
+ Including block descriptors should not cause any harm to other drives. */
+
+static int st_compression(struct scsi_tape * STp, int state)
+{
+ int retval;
+ int mpoffs; /* Offset to mode page start */
+ unsigned char *b_data = (STp->buffer)->b_data;
+
+ if (STp->ready != ST_READY)
+ return (-EIO);
+
+ /* Read the current page contents */
+ retval = read_mode_page(STp, COMPRESSION_PAGE, 0);
+ if (retval) {
+ DEBC_printk(STp, "Compression mode page not supported.\n");
+ return (-EIO);
+ }
+
+ mpoffs = MODE_HEADER_LENGTH + b_data[MH_OFF_BDESCS_LENGTH];
+ DEBC_printk(STp, "Compression state is %d.\n",
+ (b_data[mpoffs + CP_OFF_DCE_DCC] & DCE_MASK ? 1 : 0));
+
+ /* Check if compression can be changed */
+ if ((b_data[mpoffs + CP_OFF_DCE_DCC] & DCC_MASK) == 0) {
+ DEBC_printk(STp, "Compression not supported.\n");
+ return (-EIO);
+ }
+
+ /* Do the change */
+ if (state) {
+ b_data[mpoffs + CP_OFF_DCE_DCC] |= DCE_MASK;
+ if (STp->c_algo != 0)
+ b_data[mpoffs + CP_OFF_C_ALGO] = STp->c_algo;
+ }
+ else {
+ b_data[mpoffs + CP_OFF_DCE_DCC] &= ~DCE_MASK;
+ if (STp->c_algo != 0)
+ b_data[mpoffs + CP_OFF_C_ALGO] = 0; /* no compression */
+ }
+
+ retval = write_mode_page(STp, COMPRESSION_PAGE, 0);
+ if (retval) {
+ DEBC_printk(STp, "Compression change failed.\n");
+ return (-EIO);
+ }
+ DEBC_printk(STp, "Compression state changed to %d.\n", state);
+
+ STp->compression_changed = 1;
+ return 0;
+}
+
+
+/* Process the load and unload commands (does unload if the load code is zero) */
+static int do_load_unload(struct scsi_tape *STp, struct file *filp, int load_code)
+{
+ int retval = (-EIO), timeout;
+ unsigned char cmd[MAX_COMMAND_SIZE];
+ struct st_partstat *STps;
+ struct st_request *SRpnt;
+
+ if (STp->ready != ST_READY && !load_code) {
+ if (STp->ready == ST_NO_TAPE)
+ return (-ENOMEDIUM);
+ else
+ return (-EIO);
+ }
+
+ memset(cmd, 0, MAX_COMMAND_SIZE);
+ cmd[0] = START_STOP;
+ if (load_code)
+ cmd[4] |= 1;
+ /*
+ * If arg >= 1 && arg <= 6 Enhanced load/unload in HP C1553A
+ */
+ if (load_code >= 1 + MT_ST_HPLOADER_OFFSET
+ && load_code <= 6 + MT_ST_HPLOADER_OFFSET) {
+ DEBC_printk(STp, " Enhanced %sload slot %2d.\n",
+ (cmd[4]) ? "" : "un",
+ load_code - MT_ST_HPLOADER_OFFSET);
+ cmd[3] = load_code - MT_ST_HPLOADER_OFFSET; /* MediaID field of C1553A */
+ }
+ if (STp->immediate) {
+ cmd[1] = 1; /* Don't wait for completion */
+ timeout = STp->device->request_queue->rq_timeout;
+ }
+ else
+ timeout = STp->long_timeout;
+
+ DEBC(
+ if (!load_code)
+ st_printk(ST_DEB_MSG, STp, "Unloading tape.\n");
+ else
+ st_printk(ST_DEB_MSG, STp, "Loading tape.\n");
+ );
+
+ SRpnt = st_do_scsi(NULL, STp, cmd, 0, DMA_NONE,
+ timeout, MAX_RETRIES, 1);
+ if (!SRpnt)
+ return (STp->buffer)->syscall_result;
+
+ retval = (STp->buffer)->syscall_result;
+ st_release_request(SRpnt);
+
+ if (!retval) { /* SCSI command successful */
+
+ if (!load_code) {
+ STp->rew_at_close = 0;
+ STp->ready = ST_NO_TAPE;
+ }
+ else {
+ STp->rew_at_close = STp->autorew_dev;
+ retval = check_tape(STp, filp);
+ if (retval > 0)
+ retval = 0;
+ }
+ }
+ else {
+ STps = &(STp->ps[STp->partition]);
+ STps->drv_file = STps->drv_block = (-1);
+ }
+
+ return retval;
+}
+
+#if DEBUG
+#define ST_DEB_FORWARD 0
+#define ST_DEB_BACKWARD 1
+static void deb_space_print(struct scsi_tape *STp, int direction, char *units, unsigned char *cmd)
+{
+ s32 sc;
+
+ if (!debugging)
+ return;
+
+ sc = sign_extend32(get_unaligned_be24(&cmd[2]), 23);
+ if (direction)
+ sc = -sc;
+ st_printk(ST_DEB_MSG, STp, "Spacing tape %s over %d %s.\n",
+ direction ? "backward" : "forward", sc, units);
+}
+#else
+#define ST_DEB_FORWARD 0
+#define ST_DEB_BACKWARD 1
+static void deb_space_print(struct scsi_tape *STp, int direction, char *units, unsigned char *cmd) {}
+#endif
+
+
+/* Internal ioctl function */
+static int st_int_ioctl(struct scsi_tape *STp, unsigned int cmd_in, unsigned long arg)
+{
+ int timeout;
+ long ltmp;
+ int ioctl_result;
+ int chg_eof = 1;
+ unsigned char cmd[MAX_COMMAND_SIZE];
+ struct st_request *SRpnt;
+ struct st_partstat *STps;
+ int fileno, blkno, at_sm, undone;
+ int datalen = 0, direction = DMA_NONE;
+
+ WARN_ON(STp->buffer->do_dio != 0);
+ if (STp->ready != ST_READY) {
+ if (STp->ready == ST_NO_TAPE)
+ return (-ENOMEDIUM);
+ else
+ return (-EIO);
+ }
+ timeout = STp->long_timeout;
+ STps = &(STp->ps[STp->partition]);
+ fileno = STps->drv_file;
+ blkno = STps->drv_block;
+ at_sm = STps->at_sm;
+
+ memset(cmd, 0, MAX_COMMAND_SIZE);
+ switch (cmd_in) {
+ case MTFSFM:
+ chg_eof = 0; /* Changed from the FSF after this */
+ fallthrough;
+ case MTFSF:
+ cmd[0] = SPACE;
+ cmd[1] = 0x01; /* Space FileMarks */
+ cmd[2] = (arg >> 16);
+ cmd[3] = (arg >> 8);
+ cmd[4] = arg;
+ deb_space_print(STp, ST_DEB_FORWARD, "filemarks", cmd);
+ if (fileno >= 0)
+ fileno += arg;
+ blkno = 0;
+ at_sm &= (arg == 0);
+ break;
+ case MTBSFM:
+ chg_eof = 0; /* Changed from the FSF after this */
+ fallthrough;
+ case MTBSF:
+ cmd[0] = SPACE;
+ cmd[1] = 0x01; /* Space FileMarks */
+ ltmp = (-arg);
+ cmd[2] = (ltmp >> 16);
+ cmd[3] = (ltmp >> 8);
+ cmd[4] = ltmp;
+ deb_space_print(STp, ST_DEB_BACKWARD, "filemarks", cmd);
+ if (fileno >= 0)
+ fileno -= arg;
+ blkno = (-1); /* We can't know the block number */
+ at_sm &= (arg == 0);
+ break;
+ case MTFSR:
+ cmd[0] = SPACE;
+ cmd[1] = 0x00; /* Space Blocks */
+ cmd[2] = (arg >> 16);
+ cmd[3] = (arg >> 8);
+ cmd[4] = arg;
+ deb_space_print(STp, ST_DEB_FORWARD, "blocks", cmd);
+ if (blkno >= 0)
+ blkno += arg;
+ at_sm &= (arg == 0);
+ break;
+ case MTBSR:
+ cmd[0] = SPACE;
+ cmd[1] = 0x00; /* Space Blocks */
+ ltmp = (-arg);
+ cmd[2] = (ltmp >> 16);
+ cmd[3] = (ltmp >> 8);
+ cmd[4] = ltmp;
+ deb_space_print(STp, ST_DEB_BACKWARD, "blocks", cmd);
+ if (blkno >= 0)
+ blkno -= arg;
+ at_sm &= (arg == 0);
+ break;
+ case MTFSS:
+ cmd[0] = SPACE;
+ cmd[1] = 0x04; /* Space Setmarks */
+ cmd[2] = (arg >> 16);
+ cmd[3] = (arg >> 8);
+ cmd[4] = arg;
+ deb_space_print(STp, ST_DEB_FORWARD, "setmarks", cmd);
+ if (arg != 0) {
+ blkno = fileno = (-1);
+ at_sm = 1;
+ }
+ break;
+ case MTBSS:
+ cmd[0] = SPACE;
+ cmd[1] = 0x04; /* Space Setmarks */
+ ltmp = (-arg);
+ cmd[2] = (ltmp >> 16);
+ cmd[3] = (ltmp >> 8);
+ cmd[4] = ltmp;
+ deb_space_print(STp, ST_DEB_BACKWARD, "setmarks", cmd);
+ if (arg != 0) {
+ blkno = fileno = (-1);
+ at_sm = 1;
+ }
+ break;
+ case MTWEOF:
+ case MTWEOFI:
+ case MTWSM:
+ if (STp->write_prot)
+ return (-EACCES);
+ cmd[0] = WRITE_FILEMARKS;
+ if (cmd_in == MTWSM)
+ cmd[1] = 2;
+ if (cmd_in == MTWEOFI ||
+ (cmd_in == MTWEOF && STp->immediate_filemark))
+ cmd[1] |= 1;
+ cmd[2] = (arg >> 16);
+ cmd[3] = (arg >> 8);
+ cmd[4] = arg;
+ timeout = STp->device->request_queue->rq_timeout;
+ DEBC(
+ if (cmd_in != MTWSM)
+ st_printk(ST_DEB_MSG, STp,
+ "Writing %d filemarks.\n",
+ cmd[2] * 65536 +
+ cmd[3] * 256 +
+ cmd[4]);
+ else
+ st_printk(ST_DEB_MSG, STp,
+ "Writing %d setmarks.\n",
+ cmd[2] * 65536 +
+ cmd[3] * 256 +
+ cmd[4]);
+ )
+ if (fileno >= 0)
+ fileno += arg;
+ blkno = 0;
+ at_sm = (cmd_in == MTWSM);
+ break;
+ case MTREW:
+ cmd[0] = REZERO_UNIT;
+ if (STp->immediate) {
+ cmd[1] = 1; /* Don't wait for completion */
+ timeout = STp->device->request_queue->rq_timeout;
+ }
+ DEBC_printk(STp, "Rewinding tape.\n");
+ fileno = blkno = at_sm = 0;
+ break;
+ case MTNOP:
+ DEBC_printk(STp, "No op on tape.\n");
+ return 0; /* Should do something ? */
+ case MTRETEN:
+ cmd[0] = START_STOP;
+ if (STp->immediate) {
+ cmd[1] = 1; /* Don't wait for completion */
+ timeout = STp->device->request_queue->rq_timeout;
+ }
+ cmd[4] = 3;
+ DEBC_printk(STp, "Retensioning tape.\n");
+ fileno = blkno = at_sm = 0;
+ break;
+ case MTEOM:
+ if (!STp->fast_mteom) {
+ /* space to the end of tape */
+ ioctl_result = st_int_ioctl(STp, MTFSF, 0x7fffff);
+ fileno = STps->drv_file;
+ if (STps->eof >= ST_EOD_1)
+ return 0;
+ /* The next lines would hide the number of spaced FileMarks
+ That's why I inserted the previous lines. I had no luck
+ with detecting EOM with FSF, so we go now to EOM.
+ Joerg Weule */
+ } else
+ fileno = (-1);
+ cmd[0] = SPACE;
+ cmd[1] = 3;
+ DEBC_printk(STp, "Spacing to end of recorded medium.\n");
+ blkno = -1;
+ at_sm = 0;
+ break;
+ case MTERASE:
+ if (STp->write_prot)
+ return (-EACCES);
+ cmd[0] = ERASE;
+ cmd[1] = (arg ? 1 : 0); /* Long erase with non-zero argument */
+ if (STp->immediate) {
+ cmd[1] |= 2; /* Don't wait for completion */
+ timeout = STp->device->request_queue->rq_timeout;
+ }
+ else
+ timeout = STp->long_timeout * 8;
+
+ DEBC_printk(STp, "Erasing tape.\n");
+ fileno = blkno = at_sm = 0;
+ break;
+ case MTSETBLK: /* Set block length */
+ case MTSETDENSITY: /* Set tape density */
+ case MTSETDRVBUFFER: /* Set drive buffering */
+ case SET_DENS_AND_BLK: /* Set density and block size */
+ chg_eof = 0;
+ if (STp->dirty || (STp->buffer)->buffer_bytes != 0)
+ return (-EIO); /* Not allowed if data in buffer */
+ if ((cmd_in == MTSETBLK || cmd_in == SET_DENS_AND_BLK) &&
+ (arg & MT_ST_BLKSIZE_MASK) != 0 &&
+ STp->max_block > 0 &&
+ ((arg & MT_ST_BLKSIZE_MASK) < STp->min_block ||
+ (arg & MT_ST_BLKSIZE_MASK) > STp->max_block)) {
+ st_printk(KERN_WARNING, STp, "Illegal block size.\n");
+ return (-EINVAL);
+ }
+ cmd[0] = MODE_SELECT;
+ if ((STp->use_pf & USE_PF))
+ cmd[1] = MODE_SELECT_PAGE_FORMAT;
+ cmd[4] = datalen = 12;
+ direction = DMA_TO_DEVICE;
+
+ memset((STp->buffer)->b_data, 0, 12);
+ if (cmd_in == MTSETDRVBUFFER)
+ (STp->buffer)->b_data[2] = (arg & 7) << 4;
+ else
+ (STp->buffer)->b_data[2] =
+ STp->drv_buffer << 4;
+ (STp->buffer)->b_data[3] = 8; /* block descriptor length */
+ if (cmd_in == MTSETDENSITY) {
+ (STp->buffer)->b_data[4] = arg;
+ STp->density_changed = 1; /* At least we tried ;-) */
+ } else if (cmd_in == SET_DENS_AND_BLK)
+ (STp->buffer)->b_data[4] = arg >> 24;
+ else
+ (STp->buffer)->b_data[4] = STp->density;
+ if (cmd_in == MTSETBLK || cmd_in == SET_DENS_AND_BLK) {
+ ltmp = arg & MT_ST_BLKSIZE_MASK;
+ if (cmd_in == MTSETBLK)
+ STp->blksize_changed = 1; /* At least we tried ;-) */
+ } else
+ ltmp = STp->block_size;
+ (STp->buffer)->b_data[9] = (ltmp >> 16);
+ (STp->buffer)->b_data[10] = (ltmp >> 8);
+ (STp->buffer)->b_data[11] = ltmp;
+ timeout = STp->device->request_queue->rq_timeout;
+ DEBC(
+ if (cmd_in == MTSETBLK || cmd_in == SET_DENS_AND_BLK)
+ st_printk(ST_DEB_MSG, STp,
+ "Setting block size to %d bytes.\n",
+ (STp->buffer)->b_data[9] * 65536 +
+ (STp->buffer)->b_data[10] * 256 +
+ (STp->buffer)->b_data[11]);
+ if (cmd_in == MTSETDENSITY || cmd_in == SET_DENS_AND_BLK)
+ st_printk(ST_DEB_MSG, STp,
+ "Setting density code to %x.\n",
+ (STp->buffer)->b_data[4]);
+ if (cmd_in == MTSETDRVBUFFER)
+ st_printk(ST_DEB_MSG, STp,
+ "Setting drive buffer code to %d.\n",
+ ((STp->buffer)->b_data[2] >> 4) & 7);
+ )
+ break;
+ default:
+ return (-ENOSYS);
+ }
+
+ SRpnt = st_do_scsi(NULL, STp, cmd, datalen, direction,
+ timeout, MAX_RETRIES, 1);
+ if (!SRpnt)
+ return (STp->buffer)->syscall_result;
+
+ ioctl_result = (STp->buffer)->syscall_result;
+
+ if (!ioctl_result) { /* SCSI command successful */
+ st_release_request(SRpnt);
+ SRpnt = NULL;
+ STps->drv_block = blkno;
+ STps->drv_file = fileno;
+ STps->at_sm = at_sm;
+
+ if (cmd_in == MTBSFM)
+ ioctl_result = st_int_ioctl(STp, MTFSF, 1);
+ else if (cmd_in == MTFSFM)
+ ioctl_result = st_int_ioctl(STp, MTBSF, 1);
+
+ if (cmd_in == MTSETBLK || cmd_in == SET_DENS_AND_BLK) {
+ STp->block_size = arg & MT_ST_BLKSIZE_MASK;
+ if (STp->block_size != 0) {
+ (STp->buffer)->buffer_blocks =
+ (STp->buffer)->buffer_size / STp->block_size;
+ }
+ (STp->buffer)->buffer_bytes = (STp->buffer)->read_pointer = 0;
+ if (cmd_in == SET_DENS_AND_BLK)
+ STp->density = arg >> MT_ST_DENSITY_SHIFT;
+ } else if (cmd_in == MTSETDRVBUFFER)
+ STp->drv_buffer = (arg & 7);
+ else if (cmd_in == MTSETDENSITY)
+ STp->density = arg;
+
+ if (cmd_in == MTEOM)
+ STps->eof = ST_EOD;
+ else if (cmd_in == MTFSF)
+ STps->eof = ST_FM;
+ else if (chg_eof)
+ STps->eof = ST_NOEOF;
+
+ if (cmd_in == MTWEOF || cmd_in == MTWEOFI)
+ STps->rw = ST_IDLE; /* prevent automatic WEOF at close */
+ } else { /* SCSI command was not completely successful. Don't return
+ from this block without releasing the SCSI command block! */
+ struct st_cmdstatus *cmdstatp = &STp->buffer->cmdstat;
+
+ if (cmdstatp->flags & SENSE_EOM) {
+ if (cmd_in != MTBSF && cmd_in != MTBSFM &&
+ cmd_in != MTBSR && cmd_in != MTBSS)
+ STps->eof = ST_EOM_OK;
+ STps->drv_block = 0;
+ }
+
+ if (cmdstatp->remainder_valid)
+ undone = (int)cmdstatp->uremainder64;
+ else
+ undone = 0;
+
+ if ((cmd_in == MTWEOF || cmd_in == MTWEOFI) &&
+ cmdstatp->have_sense &&
+ (cmdstatp->flags & SENSE_EOM)) {
+ if (cmdstatp->sense_hdr.sense_key == NO_SENSE ||
+ cmdstatp->sense_hdr.sense_key == RECOVERED_ERROR) {
+ ioctl_result = 0; /* EOF(s) written successfully at EOM */
+ STps->eof = ST_NOEOF;
+ } else { /* Writing EOF(s) failed */
+ if (fileno >= 0)
+ fileno -= undone;
+ if (undone < arg)
+ STps->eof = ST_NOEOF;
+ }
+ STps->drv_file = fileno;
+ } else if ((cmd_in == MTFSF) || (cmd_in == MTFSFM)) {
+ if (fileno >= 0)
+ STps->drv_file = fileno - undone;
+ else
+ STps->drv_file = fileno;
+ STps->drv_block = -1;
+ STps->eof = ST_NOEOF;
+ } else if ((cmd_in == MTBSF) || (cmd_in == MTBSFM)) {
+ if (arg > 0 && undone < 0) /* Some drives get this wrong */
+ undone = (-undone);
+ if (STps->drv_file >= 0)
+ STps->drv_file = fileno + undone;
+ STps->drv_block = 0;
+ STps->eof = ST_NOEOF;
+ } else if (cmd_in == MTFSR) {
+ if (cmdstatp->flags & SENSE_FMK) { /* Hit filemark */
+ if (STps->drv_file >= 0)
+ STps->drv_file++;
+ STps->drv_block = 0;
+ STps->eof = ST_FM;
+ } else {
+ if (blkno >= undone)
+ STps->drv_block = blkno - undone;
+ else
+ STps->drv_block = (-1);
+ STps->eof = ST_NOEOF;
+ }
+ } else if (cmd_in == MTBSR) {
+ if (cmdstatp->flags & SENSE_FMK) { /* Hit filemark */
+ STps->drv_file--;
+ STps->drv_block = (-1);
+ } else {
+ if (arg > 0 && undone < 0) /* Some drives get this wrong */
+ undone = (-undone);
+ if (STps->drv_block >= 0)
+ STps->drv_block = blkno + undone;
+ }
+ STps->eof = ST_NOEOF;
+ } else if (cmd_in == MTEOM) {
+ STps->drv_file = (-1);
+ STps->drv_block = (-1);
+ STps->eof = ST_EOD;
+ } else if (cmd_in == MTSETBLK ||
+ cmd_in == MTSETDENSITY ||
+ cmd_in == MTSETDRVBUFFER ||
+ cmd_in == SET_DENS_AND_BLK) {
+ if (cmdstatp->sense_hdr.sense_key == ILLEGAL_REQUEST &&
+ !(STp->use_pf & PF_TESTED)) {
+ /* Try the other possible state of Page Format if not
+ already tried */
+ STp->use_pf = (STp->use_pf ^ USE_PF) | PF_TESTED;
+ st_release_request(SRpnt);
+ SRpnt = NULL;
+ return st_int_ioctl(STp, cmd_in, arg);
+ }
+ } else if (chg_eof)
+ STps->eof = ST_NOEOF;
+
+ if (cmdstatp->sense_hdr.sense_key == BLANK_CHECK)
+ STps->eof = ST_EOD;
+
+ st_release_request(SRpnt);
+ SRpnt = NULL;
+ }
+
+ return ioctl_result;
+}
+
+
+/* Get the tape position. If bt == 2, arg points into a kernel space mt_loc
+ structure. */
+
+static int get_location(struct scsi_tape *STp, unsigned int *block, int *partition,
+ int logical)
+{
+ int result;
+ unsigned char scmd[MAX_COMMAND_SIZE];
+ struct st_request *SRpnt;
+
+ if (STp->ready != ST_READY)
+ return (-EIO);
+
+ memset(scmd, 0, MAX_COMMAND_SIZE);
+ if ((STp->device)->scsi_level < SCSI_2) {
+ scmd[0] = QFA_REQUEST_BLOCK;
+ scmd[4] = 3;
+ } else {
+ scmd[0] = READ_POSITION;
+ if (!logical && !STp->scsi2_logical)
+ scmd[1] = 1;
+ }
+ SRpnt = st_do_scsi(NULL, STp, scmd, 20, DMA_FROM_DEVICE,
+ STp->device->request_queue->rq_timeout,
+ MAX_READY_RETRIES, 1);
+ if (!SRpnt)
+ return (STp->buffer)->syscall_result;
+
+ if ((STp->buffer)->syscall_result != 0 ||
+ (STp->device->scsi_level >= SCSI_2 &&
+ ((STp->buffer)->b_data[0] & 4) != 0)) {
+ *block = *partition = 0;
+ DEBC_printk(STp, " Can't read tape position.\n");
+ result = (-EIO);
+ } else {
+ result = 0;
+ if ((STp->device)->scsi_level < SCSI_2) {
+ *block = ((STp->buffer)->b_data[0] << 16)
+ + ((STp->buffer)->b_data[1] << 8)
+ + (STp->buffer)->b_data[2];
+ *partition = 0;
+ } else {
+ *block = ((STp->buffer)->b_data[4] << 24)
+ + ((STp->buffer)->b_data[5] << 16)
+ + ((STp->buffer)->b_data[6] << 8)
+ + (STp->buffer)->b_data[7];
+ *partition = (STp->buffer)->b_data[1];
+ if (((STp->buffer)->b_data[0] & 0x80) &&
+ (STp->buffer)->b_data[1] == 0) /* BOP of partition 0 */
+ STp->ps[0].drv_block = STp->ps[0].drv_file = 0;
+ }
+ DEBC_printk(STp, "Got tape pos. blk %d part %d.\n",
+ *block, *partition);
+ }
+ st_release_request(SRpnt);
+ SRpnt = NULL;
+
+ return result;
+}
+
+
+/* Set the tape block and partition. Negative partition means that only the
+ block should be set in vendor specific way. */
+static int set_location(struct scsi_tape *STp, unsigned int block, int partition,
+ int logical)
+{
+ struct st_partstat *STps;
+ int result, p;
+ unsigned int blk;
+ int timeout;
+ unsigned char scmd[MAX_COMMAND_SIZE];
+ struct st_request *SRpnt;
+
+ if (STp->ready != ST_READY)
+ return (-EIO);
+ timeout = STp->long_timeout;
+ STps = &(STp->ps[STp->partition]);
+
+ DEBC_printk(STp, "Setting block to %d and partition to %d.\n",
+ block, partition);
+ DEB(if (partition < 0)
+ return (-EIO); )
+
+ /* Update the location at the partition we are leaving */
+ if ((!STp->can_partitions && partition != 0) ||
+ partition >= ST_NBR_PARTITIONS)
+ return (-EINVAL);
+ if (partition != STp->partition) {
+ if (get_location(STp, &blk, &p, 1))
+ STps->last_block_valid = 0;
+ else {
+ STps->last_block_valid = 1;
+ STps->last_block_visited = blk;
+ DEBC_printk(STp, "Visited block %d for "
+ "partition %d saved.\n",
+ blk, STp->partition);
+ }
+ }
+
+ memset(scmd, 0, MAX_COMMAND_SIZE);
+ if ((STp->device)->scsi_level < SCSI_2) {
+ scmd[0] = QFA_SEEK_BLOCK;
+ scmd[2] = (block >> 16);
+ scmd[3] = (block >> 8);
+ scmd[4] = block;
+ scmd[5] = 0;
+ } else {
+ scmd[0] = SEEK_10;
+ scmd[3] = (block >> 24);
+ scmd[4] = (block >> 16);
+ scmd[5] = (block >> 8);
+ scmd[6] = block;
+ if (!logical && !STp->scsi2_logical)
+ scmd[1] = 4;
+ if (STp->partition != partition) {
+ scmd[1] |= 2;
+ scmd[8] = partition;
+ DEBC_printk(STp, "Trying to change partition "
+ "from %d to %d\n", STp->partition,
+ partition);
+ }
+ }
+ if (STp->immediate) {
+ scmd[1] |= 1; /* Don't wait for completion */
+ timeout = STp->device->request_queue->rq_timeout;
+ }
+
+ SRpnt = st_do_scsi(NULL, STp, scmd, 0, DMA_NONE,
+ timeout, MAX_READY_RETRIES, 1);
+ if (!SRpnt)
+ return (STp->buffer)->syscall_result;
+
+ STps->drv_block = STps->drv_file = (-1);
+ STps->eof = ST_NOEOF;
+ if ((STp->buffer)->syscall_result != 0) {
+ result = (-EIO);
+ if (STp->can_partitions &&
+ (STp->device)->scsi_level >= SCSI_2 &&
+ (p = find_partition(STp)) >= 0)
+ STp->partition = p;
+ } else {
+ if (STp->can_partitions) {
+ STp->partition = partition;
+ STps = &(STp->ps[partition]);
+ if (!STps->last_block_valid ||
+ STps->last_block_visited != block) {
+ STps->at_sm = 0;
+ STps->rw = ST_IDLE;
+ }
+ } else
+ STps->at_sm = 0;
+ if (block == 0)
+ STps->drv_block = STps->drv_file = 0;
+ result = 0;
+ }
+
+ st_release_request(SRpnt);
+ SRpnt = NULL;
+
+ return result;
+}
+
+
+/* Find the current partition number for the drive status. Called from open and
+ returns either partition number of negative error code. */
+static int find_partition(struct scsi_tape *STp)
+{
+ int i, partition;
+ unsigned int block;
+
+ if ((i = get_location(STp, &block, &partition, 1)) < 0)
+ return i;
+ if (partition >= ST_NBR_PARTITIONS)
+ return (-EIO);
+ return partition;
+}
+
+
+/* Change the partition if necessary */
+static int switch_partition(struct scsi_tape *STp)
+{
+ struct st_partstat *STps;
+
+ if (STp->partition == STp->new_partition)
+ return 0;
+ STps = &(STp->ps[STp->new_partition]);
+ if (!STps->last_block_valid)
+ STps->last_block_visited = 0;
+ return set_location(STp, STps->last_block_visited, STp->new_partition, 1);
+}
+
+/* Functions for reading and writing the medium partition mode page. */
+
+#define PART_PAGE 0x11
+#define PART_PAGE_FIXED_LENGTH 8
+
+#define PP_OFF_MAX_ADD_PARTS 2
+#define PP_OFF_NBR_ADD_PARTS 3
+#define PP_OFF_FLAGS 4
+#define PP_OFF_PART_UNITS 6
+#define PP_OFF_RESERVED 7
+
+#define PP_BIT_IDP 0x20
+#define PP_BIT_FDP 0x80
+#define PP_MSK_PSUM_MB 0x10
+#define PP_MSK_PSUM_UNITS 0x18
+#define PP_MSK_POFM 0x04
+
+/* Get the number of partitions on the tape. As a side effect reads the
+ mode page into the tape buffer. */
+static int nbr_partitions(struct scsi_tape *STp)
+{
+ int result;
+
+ if (STp->ready != ST_READY)
+ return (-EIO);
+
+ result = read_mode_page(STp, PART_PAGE, 1);
+
+ if (result) {
+ DEBC_printk(STp, "Can't read medium partition page.\n");
+ result = (-EIO);
+ } else {
+ result = (STp->buffer)->b_data[MODE_HEADER_LENGTH +
+ PP_OFF_NBR_ADD_PARTS] + 1;
+ DEBC_printk(STp, "Number of partitions %d.\n", result);
+ }
+
+ return result;
+}
+
+
+static int format_medium(struct scsi_tape *STp, int format)
+{
+ int result = 0;
+ int timeout = STp->long_timeout;
+ unsigned char scmd[MAX_COMMAND_SIZE];
+ struct st_request *SRpnt;
+
+ memset(scmd, 0, MAX_COMMAND_SIZE);
+ scmd[0] = FORMAT_UNIT;
+ scmd[2] = format;
+ if (STp->immediate) {
+ scmd[1] |= 1; /* Don't wait for completion */
+ timeout = STp->device->request_queue->rq_timeout;
+ }
+ DEBC_printk(STp, "Sending FORMAT MEDIUM\n");
+ SRpnt = st_do_scsi(NULL, STp, scmd, 0, DMA_NONE,
+ timeout, MAX_RETRIES, 1);
+ if (!SRpnt)
+ result = STp->buffer->syscall_result;
+ return result;
+}
+
+
+/* Partition the tape into two partitions if size > 0 or one partition if
+ size == 0.
+
+ The block descriptors are read and written because Sony SDT-7000 does not
+ work without this (suggestion from Michael Schaefer <Michael.Schaefer@dlr.de>).
+
+ My HP C1533A drive returns only one partition size field. This is used to
+ set the size of partition 1. There is no size field for the default partition.
+ Michael Schaefer's Sony SDT-7000 returns two descriptors and the second is
+ used to set the size of partition 1 (this is what the SCSI-3 standard specifies).
+ The following algorithm is used to accommodate both drives: if the number of
+ partition size fields is greater than the maximum number of additional partitions
+ in the mode page, the second field is used. Otherwise the first field is used.
+
+ For Seagate DDS drives the page length must be 8 when no partitions is defined
+ and 10 when 1 partition is defined (information from Eric Lee Green). This is
+ is acceptable also to some other old drives and enforced if the first partition
+ size field is used for the first additional partition size.
+
+ For drives that advertize SCSI-3 or newer, use the SSC-3 methods.
+ */
+static int partition_tape(struct scsi_tape *STp, int size)
+{
+ int result;
+ int target_partition;
+ bool scsi3 = STp->device->scsi_level >= SCSI_3, needs_format = false;
+ int pgo, psd_cnt, psdo;
+ int psum = PP_MSK_PSUM_MB, units = 0;
+ unsigned char *bp;
+
+ result = read_mode_page(STp, PART_PAGE, 0);
+ if (result) {
+ DEBC_printk(STp, "Can't read partition mode page.\n");
+ return result;
+ }
+ target_partition = 1;
+ if (size < 0) {
+ target_partition = 0;
+ size = -size;
+ }
+
+ /* The mode page is in the buffer. Let's modify it and write it. */
+ bp = (STp->buffer)->b_data;
+ pgo = MODE_HEADER_LENGTH + bp[MH_OFF_BDESCS_LENGTH];
+ DEBC_printk(STp, "Partition page length is %d bytes.\n",
+ bp[pgo + MP_OFF_PAGE_LENGTH] + 2);
+
+ psd_cnt = (bp[pgo + MP_OFF_PAGE_LENGTH] + 2 - PART_PAGE_FIXED_LENGTH) / 2;
+
+ if (scsi3) {
+ needs_format = (bp[pgo + PP_OFF_FLAGS] & PP_MSK_POFM) != 0;
+ if (needs_format && size == 0) {
+ /* No need to write the mode page when clearing
+ * partitioning
+ */
+ DEBC_printk(STp, "Formatting tape with one partition.\n");
+ result = format_medium(STp, 0);
+ goto out;
+ }
+ if (needs_format) /* Leave the old value for HP DATs claiming SCSI_3 */
+ psd_cnt = 2;
+ if ((bp[pgo + PP_OFF_FLAGS] & PP_MSK_PSUM_UNITS) == PP_MSK_PSUM_UNITS) {
+ /* Use units scaling for large partitions if the device
+ * suggests it and no precision lost. Required for IBM
+ * TS1140/50 drives that don't support MB units.
+ */
+ if (size >= 1000 && (size % 1000) == 0) {
+ size /= 1000;
+ psum = PP_MSK_PSUM_UNITS;
+ units = 9; /* GB */
+ }
+ }
+ /* Try it anyway if too large to specify in MB */
+ if (psum == PP_MSK_PSUM_MB && size >= 65534) {
+ size /= 1000;
+ psum = PP_MSK_PSUM_UNITS;
+ units = 9; /* GB */
+ }
+ }
+
+ if (size >= 65535 || /* Does not fit into two bytes */
+ (target_partition == 0 && psd_cnt < 2)) {
+ result = -EINVAL;
+ goto out;
+ }
+
+ psdo = pgo + PART_PAGE_FIXED_LENGTH;
+ /* The second condition is for HP DDS which use only one partition size
+ * descriptor
+ */
+ if (target_partition > 0 &&
+ (psd_cnt > bp[pgo + PP_OFF_MAX_ADD_PARTS] ||
+ bp[pgo + PP_OFF_MAX_ADD_PARTS] != 1)) {
+ bp[psdo] = bp[psdo + 1] = 0xff; /* Rest to partition 0 */
+ psdo += 2;
+ }
+ memset(bp + psdo, 0, bp[pgo + PP_OFF_NBR_ADD_PARTS] * 2);
+
+ DEBC_printk(STp, "psd_cnt %d, max.parts %d, nbr_parts %d\n",
+ psd_cnt, bp[pgo + PP_OFF_MAX_ADD_PARTS],
+ bp[pgo + PP_OFF_NBR_ADD_PARTS]);
+
+ if (size == 0) {
+ bp[pgo + PP_OFF_NBR_ADD_PARTS] = 0;
+ if (psd_cnt <= bp[pgo + PP_OFF_MAX_ADD_PARTS])
+ bp[pgo + MP_OFF_PAGE_LENGTH] = 6;
+ DEBC_printk(STp, "Formatting tape with one partition.\n");
+ } else {
+ bp[psdo] = (size >> 8) & 0xff;
+ bp[psdo + 1] = size & 0xff;
+ if (target_partition == 0)
+ bp[psdo + 2] = bp[psdo + 3] = 0xff;
+ bp[pgo + 3] = 1;
+ if (bp[pgo + MP_OFF_PAGE_LENGTH] < 8)
+ bp[pgo + MP_OFF_PAGE_LENGTH] = 8;
+ DEBC_printk(STp,
+ "Formatting tape with two partitions (%i = %d MB).\n",
+ target_partition, units > 0 ? size * 1000 : size);
+ }
+ bp[pgo + PP_OFF_PART_UNITS] = 0;
+ bp[pgo + PP_OFF_RESERVED] = 0;
+ if (size != 1 || units != 0) {
+ bp[pgo + PP_OFF_FLAGS] = PP_BIT_IDP | psum |
+ (bp[pgo + PP_OFF_FLAGS] & 0x07);
+ bp[pgo + PP_OFF_PART_UNITS] = units;
+ } else
+ bp[pgo + PP_OFF_FLAGS] = PP_BIT_FDP |
+ (bp[pgo + PP_OFF_FLAGS] & 0x1f);
+ bp[pgo + MP_OFF_PAGE_LENGTH] = 6 + psd_cnt * 2;
+
+ result = write_mode_page(STp, PART_PAGE, 1);
+
+ if (!result && needs_format)
+ result = format_medium(STp, 1);
+
+ if (result) {
+ st_printk(KERN_INFO, STp, "Partitioning of tape failed.\n");
+ result = (-EIO);
+ }
+
+out:
+ return result;
+}
+
+
+
+/* The ioctl command */
+static long st_ioctl(struct file *file, unsigned int cmd_in, unsigned long arg)
+{
+ void __user *p = (void __user *)arg;
+ int i, cmd_nr, cmd_type, bt;
+ int retval = 0;
+ unsigned int blk;
+ struct scsi_tape *STp = file->private_data;
+ struct st_modedef *STm;
+ struct st_partstat *STps;
+
+ if (mutex_lock_interruptible(&STp->lock))
+ return -ERESTARTSYS;
+
+ DEB(
+ if (debugging && !STp->in_use) {
+ st_printk(ST_DEB_MSG, STp, "Incorrect device.\n");
+ retval = (-EIO);
+ goto out;
+ } ) /* end DEB */
+
+ STm = &(STp->modes[STp->current_mode]);
+ STps = &(STp->ps[STp->partition]);
+
+ /*
+ * If we are in the middle of error recovery, don't let anyone
+ * else try and use this device. Also, if error recovery fails, it
+ * may try and take the device offline, in which case all further
+ * access to the device is prohibited.
+ */
+ retval = scsi_ioctl_block_when_processing_errors(STp->device, cmd_in,
+ file->f_flags & O_NDELAY);
+ if (retval)
+ goto out;
+
+ cmd_type = _IOC_TYPE(cmd_in);
+ cmd_nr = _IOC_NR(cmd_in);
+
+ if (cmd_type == _IOC_TYPE(MTIOCTOP) && cmd_nr == _IOC_NR(MTIOCTOP)) {
+ struct mtop mtc;
+
+ if (_IOC_SIZE(cmd_in) != sizeof(mtc)) {
+ retval = (-EINVAL);
+ goto out;
+ }
+
+ i = copy_from_user(&mtc, p, sizeof(struct mtop));
+ if (i) {
+ retval = (-EFAULT);
+ goto out;
+ }
+
+ if (mtc.mt_op == MTSETDRVBUFFER && !capable(CAP_SYS_ADMIN)) {
+ st_printk(KERN_WARNING, STp,
+ "MTSETDRVBUFFER only allowed for root.\n");
+ retval = (-EPERM);
+ goto out;
+ }
+ if (!STm->defined &&
+ (mtc.mt_op != MTSETDRVBUFFER &&
+ (mtc.mt_count & MT_ST_OPTIONS) == 0)) {
+ retval = (-ENXIO);
+ goto out;
+ }
+
+ if (!STp->pos_unknown) {
+
+ if (STps->eof == ST_FM_HIT) {
+ if (mtc.mt_op == MTFSF || mtc.mt_op == MTFSFM ||
+ mtc.mt_op == MTEOM) {
+ mtc.mt_count -= 1;
+ if (STps->drv_file >= 0)
+ STps->drv_file += 1;
+ } else if (mtc.mt_op == MTBSF || mtc.mt_op == MTBSFM) {
+ mtc.mt_count += 1;
+ if (STps->drv_file >= 0)
+ STps->drv_file += 1;
+ }
+ }
+
+ if (mtc.mt_op == MTSEEK) {
+ /* Old position must be restored if partition will be
+ changed */
+ i = !STp->can_partitions ||
+ (STp->new_partition != STp->partition);
+ } else {
+ i = mtc.mt_op == MTREW || mtc.mt_op == MTOFFL ||
+ mtc.mt_op == MTRETEN || mtc.mt_op == MTEOM ||
+ mtc.mt_op == MTLOCK || mtc.mt_op == MTLOAD ||
+ mtc.mt_op == MTFSF || mtc.mt_op == MTFSFM ||
+ mtc.mt_op == MTBSF || mtc.mt_op == MTBSFM ||
+ mtc.mt_op == MTCOMPRESSION;
+ }
+ i = flush_buffer(STp, i);
+ if (i < 0) {
+ retval = i;
+ goto out;
+ }
+ if (STps->rw == ST_WRITING &&
+ (mtc.mt_op == MTREW || mtc.mt_op == MTOFFL ||
+ mtc.mt_op == MTSEEK ||
+ mtc.mt_op == MTBSF || mtc.mt_op == MTBSFM)) {
+ i = st_int_ioctl(STp, MTWEOF, 1);
+ if (i < 0) {
+ retval = i;
+ goto out;
+ }
+ if (mtc.mt_op == MTBSF || mtc.mt_op == MTBSFM)
+ mtc.mt_count++;
+ STps->rw = ST_IDLE;
+ }
+
+ } else {
+ /*
+ * If there was a bus reset, block further access
+ * to this device. If the user wants to rewind the tape,
+ * then reset the flag and allow access again.
+ */
+ if (mtc.mt_op != MTREW &&
+ mtc.mt_op != MTOFFL &&
+ mtc.mt_op != MTRETEN &&
+ mtc.mt_op != MTERASE &&
+ mtc.mt_op != MTSEEK &&
+ mtc.mt_op != MTEOM) {
+ retval = (-EIO);
+ goto out;
+ }
+ reset_state(STp);
+ /* remove this when the midlevel properly clears was_reset */
+ STp->device->was_reset = 0;
+ }
+
+ if (mtc.mt_op != MTNOP && mtc.mt_op != MTSETBLK &&
+ mtc.mt_op != MTSETDENSITY && mtc.mt_op != MTWSM &&
+ mtc.mt_op != MTSETDRVBUFFER && mtc.mt_op != MTSETPART)
+ STps->rw = ST_IDLE; /* Prevent automatic WEOF and fsf */
+
+ if (mtc.mt_op == MTOFFL && STp->door_locked != ST_UNLOCKED)
+ do_door_lock(STp, 0); /* Ignore result! */
+
+ if (mtc.mt_op == MTSETDRVBUFFER &&
+ (mtc.mt_count & MT_ST_OPTIONS) != 0) {
+ retval = st_set_options(STp, mtc.mt_count);
+ goto out;
+ }
+
+ if (mtc.mt_op == MTSETPART) {
+ if (!STp->can_partitions ||
+ mtc.mt_count < 0 || mtc.mt_count >= ST_NBR_PARTITIONS) {
+ retval = (-EINVAL);
+ goto out;
+ }
+ if (mtc.mt_count >= STp->nbr_partitions &&
+ (STp->nbr_partitions = nbr_partitions(STp)) < 0) {
+ retval = (-EIO);
+ goto out;
+ }
+ if (mtc.mt_count >= STp->nbr_partitions) {
+ retval = (-EINVAL);
+ goto out;
+ }
+ STp->new_partition = mtc.mt_count;
+ retval = 0;
+ goto out;
+ }
+
+ if (mtc.mt_op == MTMKPART) {
+ if (!STp->can_partitions) {
+ retval = (-EINVAL);
+ goto out;
+ }
+ i = do_load_unload(STp, file, 1);
+ if (i < 0) {
+ retval = i;
+ goto out;
+ }
+ i = partition_tape(STp, mtc.mt_count);
+ if (i < 0) {
+ retval = i;
+ goto out;
+ }
+ for (i = 0; i < ST_NBR_PARTITIONS; i++) {
+ STp->ps[i].rw = ST_IDLE;
+ STp->ps[i].at_sm = 0;
+ STp->ps[i].last_block_valid = 0;
+ }
+ STp->partition = STp->new_partition = 0;
+ STp->nbr_partitions = mtc.mt_count != 0 ? 2 : 1;
+ STps->drv_block = STps->drv_file = 0;
+ retval = 0;
+ goto out;
+ }
+
+ if (mtc.mt_op == MTSEEK) {
+ i = set_location(STp, mtc.mt_count, STp->new_partition, 0);
+ if (!STp->can_partitions)
+ STp->ps[0].rw = ST_IDLE;
+ retval = i;
+ goto out;
+ }
+
+ if (mtc.mt_op == MTUNLOAD || mtc.mt_op == MTOFFL) {
+ retval = do_load_unload(STp, file, 0);
+ goto out;
+ }
+
+ if (mtc.mt_op == MTLOAD) {
+ retval = do_load_unload(STp, file, max(1, mtc.mt_count));
+ goto out;
+ }
+
+ if (mtc.mt_op == MTLOCK || mtc.mt_op == MTUNLOCK) {
+ retval = do_door_lock(STp, (mtc.mt_op == MTLOCK));
+ goto out;
+ }
+
+ if (STp->can_partitions && STp->ready == ST_READY &&
+ (i = switch_partition(STp)) < 0) {
+ retval = i;
+ goto out;
+ }
+
+ if (mtc.mt_op == MTCOMPRESSION)
+ retval = st_compression(STp, (mtc.mt_count & 1));
+ else
+ retval = st_int_ioctl(STp, mtc.mt_op, mtc.mt_count);
+ goto out;
+ }
+ if (!STm->defined) {
+ retval = (-ENXIO);
+ goto out;
+ }
+
+ if ((i = flush_buffer(STp, 0)) < 0) {
+ retval = i;
+ goto out;
+ }
+ if (STp->can_partitions &&
+ (i = switch_partition(STp)) < 0) {
+ retval = i;
+ goto out;
+ }
+
+ if (cmd_type == _IOC_TYPE(MTIOCGET) && cmd_nr == _IOC_NR(MTIOCGET)) {
+ struct mtget mt_status;
+
+ if (_IOC_SIZE(cmd_in) != sizeof(struct mtget)) {
+ retval = (-EINVAL);
+ goto out;
+ }
+
+ mt_status.mt_type = STp->tape_type;
+ mt_status.mt_dsreg =
+ ((STp->block_size << MT_ST_BLKSIZE_SHIFT) & MT_ST_BLKSIZE_MASK) |
+ ((STp->density << MT_ST_DENSITY_SHIFT) & MT_ST_DENSITY_MASK);
+ mt_status.mt_blkno = STps->drv_block;
+ mt_status.mt_fileno = STps->drv_file;
+ if (STp->block_size != 0) {
+ if (STps->rw == ST_WRITING)
+ mt_status.mt_blkno +=
+ (STp->buffer)->buffer_bytes / STp->block_size;
+ else if (STps->rw == ST_READING)
+ mt_status.mt_blkno -=
+ ((STp->buffer)->buffer_bytes +
+ STp->block_size - 1) / STp->block_size;
+ }
+
+ mt_status.mt_gstat = 0;
+ if (STp->drv_write_prot)
+ mt_status.mt_gstat |= GMT_WR_PROT(0xffffffff);
+ if (mt_status.mt_blkno == 0) {
+ if (mt_status.mt_fileno == 0)
+ mt_status.mt_gstat |= GMT_BOT(0xffffffff);
+ else
+ mt_status.mt_gstat |= GMT_EOF(0xffffffff);
+ }
+ mt_status.mt_erreg = (STp->recover_reg << MT_ST_SOFTERR_SHIFT);
+ mt_status.mt_resid = STp->partition;
+ if (STps->eof == ST_EOM_OK || STps->eof == ST_EOM_ERROR)
+ mt_status.mt_gstat |= GMT_EOT(0xffffffff);
+ else if (STps->eof >= ST_EOM_OK)
+ mt_status.mt_gstat |= GMT_EOD(0xffffffff);
+ if (STp->density == 1)
+ mt_status.mt_gstat |= GMT_D_800(0xffffffff);
+ else if (STp->density == 2)
+ mt_status.mt_gstat |= GMT_D_1600(0xffffffff);
+ else if (STp->density == 3)
+ mt_status.mt_gstat |= GMT_D_6250(0xffffffff);
+ if (STp->ready == ST_READY)
+ mt_status.mt_gstat |= GMT_ONLINE(0xffffffff);
+ if (STp->ready == ST_NO_TAPE)
+ mt_status.mt_gstat |= GMT_DR_OPEN(0xffffffff);
+ if (STps->at_sm)
+ mt_status.mt_gstat |= GMT_SM(0xffffffff);
+ if (STm->do_async_writes ||
+ (STm->do_buffer_writes && STp->block_size != 0) ||
+ STp->drv_buffer != 0)
+ mt_status.mt_gstat |= GMT_IM_REP_EN(0xffffffff);
+ if (STp->cleaning_req)
+ mt_status.mt_gstat |= GMT_CLN(0xffffffff);
+
+ retval = put_user_mtget(p, &mt_status);
+ if (retval)
+ goto out;
+
+ STp->recover_reg = 0; /* Clear after read */
+ goto out;
+ } /* End of MTIOCGET */
+ if (cmd_type == _IOC_TYPE(MTIOCPOS) && cmd_nr == _IOC_NR(MTIOCPOS)) {
+ struct mtpos mt_pos;
+ if (_IOC_SIZE(cmd_in) != sizeof(struct mtpos)) {
+ retval = (-EINVAL);
+ goto out;
+ }
+ if ((i = get_location(STp, &blk, &bt, 0)) < 0) {
+ retval = i;
+ goto out;
+ }
+ mt_pos.mt_blkno = blk;
+ retval = put_user_mtpos(p, &mt_pos);
+ goto out;
+ }
+ mutex_unlock(&STp->lock);
+
+ switch (cmd_in) {
+ case SG_IO:
+ case SCSI_IOCTL_SEND_COMMAND:
+ case CDROM_SEND_PACKET:
+ if (!capable(CAP_SYS_RAWIO))
+ return -EPERM;
+ break;
+ default:
+ break;
+ }
+
+ retval = scsi_ioctl(STp->device, file->f_mode, cmd_in, p);
+ if (!retval && cmd_in == SCSI_IOCTL_STOP_UNIT) {
+ /* unload */
+ STp->rew_at_close = 0;
+ STp->ready = ST_NO_TAPE;
+ }
+ return retval;
+
+ out:
+ mutex_unlock(&STp->lock);
+ return retval;
+}
+
+#ifdef CONFIG_COMPAT
+static long st_compat_ioctl(struct file *file, unsigned int cmd_in, unsigned long arg)
+{
+ /* argument conversion is handled using put_user_mtpos/put_user_mtget */
+ switch (cmd_in) {
+ case MTIOCPOS32:
+ cmd_in = MTIOCPOS;
+ break;
+ case MTIOCGET32:
+ cmd_in = MTIOCGET;
+ break;
+ }
+
+ return st_ioctl(file, cmd_in, arg);
+}
+#endif
+
+
+
+/* Try to allocate a new tape buffer. Calling function must not hold
+ dev_arr_lock. */
+static struct st_buffer *new_tape_buffer(int max_sg)
+{
+ struct st_buffer *tb;
+
+ tb = kzalloc(sizeof(struct st_buffer), GFP_KERNEL);
+ if (!tb) {
+ printk(KERN_NOTICE "st: Can't allocate new tape buffer.\n");
+ return NULL;
+ }
+ tb->frp_segs = 0;
+ tb->use_sg = max_sg;
+ tb->buffer_size = 0;
+
+ tb->reserved_pages = kcalloc(max_sg, sizeof(struct page *),
+ GFP_KERNEL);
+ if (!tb->reserved_pages) {
+ kfree(tb);
+ return NULL;
+ }
+
+ return tb;
+}
+
+
+/* Try to allocate enough space in the tape buffer */
+#define ST_MAX_ORDER 6
+
+static int enlarge_buffer(struct st_buffer * STbuffer, int new_size)
+{
+ int segs, max_segs, b_size, order, got;
+ gfp_t priority;
+
+ if (new_size <= STbuffer->buffer_size)
+ return 1;
+
+ if (STbuffer->buffer_size <= PAGE_SIZE)
+ normalize_buffer(STbuffer); /* Avoid extra segment */
+
+ max_segs = STbuffer->use_sg;
+
+ priority = GFP_KERNEL | __GFP_NOWARN;
+
+ if (STbuffer->cleared)
+ priority |= __GFP_ZERO;
+
+ if (STbuffer->frp_segs) {
+ order = STbuffer->reserved_page_order;
+ b_size = PAGE_SIZE << order;
+ } else {
+ for (b_size = PAGE_SIZE, order = 0;
+ order < ST_MAX_ORDER &&
+ max_segs * (PAGE_SIZE << order) < new_size;
+ order++, b_size *= 2)
+ ; /* empty */
+ STbuffer->reserved_page_order = order;
+ }
+ if (max_segs * (PAGE_SIZE << order) < new_size) {
+ if (order == ST_MAX_ORDER)
+ return 0;
+ normalize_buffer(STbuffer);
+ return enlarge_buffer(STbuffer, new_size);
+ }
+
+ for (segs = STbuffer->frp_segs, got = STbuffer->buffer_size;
+ segs < max_segs && got < new_size;) {
+ struct page *page;
+
+ page = alloc_pages(priority, order);
+ if (!page) {
+ DEB(STbuffer->buffer_size = got);
+ normalize_buffer(STbuffer);
+ return 0;
+ }
+
+ STbuffer->frp_segs += 1;
+ got += b_size;
+ STbuffer->buffer_size = got;
+ STbuffer->reserved_pages[segs] = page;
+ segs++;
+ }
+ STbuffer->b_data = page_address(STbuffer->reserved_pages[0]);
+
+ return 1;
+}
+
+
+/* Make sure that no data from previous user is in the internal buffer */
+static void clear_buffer(struct st_buffer * st_bp)
+{
+ int i;
+
+ for (i=0; i < st_bp->frp_segs; i++)
+ memset(page_address(st_bp->reserved_pages[i]), 0,
+ PAGE_SIZE << st_bp->reserved_page_order);
+ st_bp->cleared = 1;
+}
+
+
+/* Release the extra buffer */
+static void normalize_buffer(struct st_buffer * STbuffer)
+{
+ int i, order = STbuffer->reserved_page_order;
+
+ for (i = 0; i < STbuffer->frp_segs; i++) {
+ __free_pages(STbuffer->reserved_pages[i], order);
+ STbuffer->buffer_size -= (PAGE_SIZE << order);
+ }
+ STbuffer->frp_segs = 0;
+ STbuffer->sg_segs = 0;
+ STbuffer->reserved_page_order = 0;
+ STbuffer->map_data.offset = 0;
+}
+
+
+/* Move data from the user buffer to the tape buffer. Returns zero (success) or
+ negative error code. */
+static int append_to_buffer(const char __user *ubp, struct st_buffer * st_bp, int do_count)
+{
+ int i, cnt, res, offset;
+ int length = PAGE_SIZE << st_bp->reserved_page_order;
+
+ for (i = 0, offset = st_bp->buffer_bytes;
+ i < st_bp->frp_segs && offset >= length; i++)
+ offset -= length;
+ if (i == st_bp->frp_segs) { /* Should never happen */
+ printk(KERN_WARNING "st: append_to_buffer offset overflow.\n");
+ return (-EIO);
+ }
+ for (; i < st_bp->frp_segs && do_count > 0; i++) {
+ struct page *page = st_bp->reserved_pages[i];
+ cnt = length - offset < do_count ? length - offset : do_count;
+ res = copy_from_user(page_address(page) + offset, ubp, cnt);
+ if (res)
+ return (-EFAULT);
+ do_count -= cnt;
+ st_bp->buffer_bytes += cnt;
+ ubp += cnt;
+ offset = 0;
+ }
+ if (do_count) /* Should never happen */
+ return (-EIO);
+
+ return 0;
+}
+
+
+/* Move data from the tape buffer to the user buffer. Returns zero (success) or
+ negative error code. */
+static int from_buffer(struct st_buffer * st_bp, char __user *ubp, int do_count)
+{
+ int i, cnt, res, offset;
+ int length = PAGE_SIZE << st_bp->reserved_page_order;
+
+ for (i = 0, offset = st_bp->read_pointer;
+ i < st_bp->frp_segs && offset >= length; i++)
+ offset -= length;
+ if (i == st_bp->frp_segs) { /* Should never happen */
+ printk(KERN_WARNING "st: from_buffer offset overflow.\n");
+ return (-EIO);
+ }
+ for (; i < st_bp->frp_segs && do_count > 0; i++) {
+ struct page *page = st_bp->reserved_pages[i];
+ cnt = length - offset < do_count ? length - offset : do_count;
+ res = copy_to_user(ubp, page_address(page) + offset, cnt);
+ if (res)
+ return (-EFAULT);
+ do_count -= cnt;
+ st_bp->buffer_bytes -= cnt;
+ st_bp->read_pointer += cnt;
+ ubp += cnt;
+ offset = 0;
+ }
+ if (do_count) /* Should never happen */
+ return (-EIO);
+
+ return 0;
+}
+
+
+/* Move data towards start of buffer */
+static void move_buffer_data(struct st_buffer * st_bp, int offset)
+{
+ int src_seg, dst_seg, src_offset = 0, dst_offset;
+ int count, total;
+ int length = PAGE_SIZE << st_bp->reserved_page_order;
+
+ if (offset == 0)
+ return;
+
+ total=st_bp->buffer_bytes - offset;
+ for (src_seg=0; src_seg < st_bp->frp_segs; src_seg++) {
+ src_offset = offset;
+ if (src_offset < length)
+ break;
+ offset -= length;
+ }
+
+ st_bp->buffer_bytes = st_bp->read_pointer = total;
+ for (dst_seg=dst_offset=0; total > 0; ) {
+ struct page *dpage = st_bp->reserved_pages[dst_seg];
+ struct page *spage = st_bp->reserved_pages[src_seg];
+
+ count = min(length - dst_offset, length - src_offset);
+ memmove(page_address(dpage) + dst_offset,
+ page_address(spage) + src_offset, count);
+ src_offset += count;
+ if (src_offset >= length) {
+ src_seg++;
+ src_offset = 0;
+ }
+ dst_offset += count;
+ if (dst_offset >= length) {
+ dst_seg++;
+ dst_offset = 0;
+ }
+ total -= count;
+ }
+}
+
+/* Validate the options from command line or module parameters */
+static void validate_options(void)
+{
+ if (buffer_kbs > 0)
+ st_fixed_buffer_size = buffer_kbs * ST_KILOBYTE;
+ if (max_sg_segs >= ST_FIRST_SG)
+ st_max_sg_segs = max_sg_segs;
+}
+
+#ifndef MODULE
+/* Set the boot options. Syntax is defined in Documenation/scsi/st.txt.
+ */
+static int __init st_setup(char *str)
+{
+ int i, len, ints[5];
+ char *stp;
+
+ stp = get_options(str, ARRAY_SIZE(ints), ints);
+
+ if (ints[0] > 0) {
+ for (i = 0; i < ints[0] && i < ARRAY_SIZE(parms); i++)
+ if (parms[i].val)
+ *parms[i].val = ints[i + 1];
+ } else {
+ while (stp != NULL) {
+ for (i = 0; i < ARRAY_SIZE(parms); i++) {
+ len = strlen(parms[i].name);
+ if (!strncmp(stp, parms[i].name, len) &&
+ (*(stp + len) == ':' || *(stp + len) == '=')) {
+ if (parms[i].val)
+ *parms[i].val =
+ simple_strtoul(stp + len + 1, NULL, 0);
+ else
+ printk(KERN_WARNING "st: Obsolete parameter %s\n",
+ parms[i].name);
+ break;
+ }
+ }
+ if (i >= ARRAY_SIZE(parms))
+ printk(KERN_WARNING "st: invalid parameter in '%s'\n",
+ stp);
+ stp = strchr(stp, ',');
+ if (stp)
+ stp++;
+ }
+ }
+
+ validate_options();
+
+ return 1;
+}
+
+__setup("st=", st_setup);
+
+#endif
+
+static const struct file_operations st_fops =
+{
+ .owner = THIS_MODULE,
+ .read = st_read,
+ .write = st_write,
+ .unlocked_ioctl = st_ioctl,
+#ifdef CONFIG_COMPAT
+ .compat_ioctl = st_compat_ioctl,
+#endif
+ .open = st_open,
+ .flush = st_flush,
+ .release = st_release,
+ .llseek = noop_llseek,
+};
+
+static int create_one_cdev(struct scsi_tape *tape, int mode, int rew)
+{
+ int i, error;
+ dev_t cdev_devno;
+ struct cdev *cdev;
+ struct device *dev;
+ struct st_modedef *STm = &(tape->modes[mode]);
+ char name[10];
+ int dev_num = tape->index;
+
+ cdev_devno = MKDEV(SCSI_TAPE_MAJOR, TAPE_MINOR(dev_num, mode, rew));
+
+ cdev = cdev_alloc();
+ if (!cdev) {
+ pr_err("st%d: out of memory. Device not attached.\n", dev_num);
+ error = -ENOMEM;
+ goto out;
+ }
+ cdev->owner = THIS_MODULE;
+ cdev->ops = &st_fops;
+ STm->cdevs[rew] = cdev;
+
+ error = cdev_add(cdev, cdev_devno, 1);
+ if (error) {
+ pr_err("st%d: Can't add %s-rewind mode %d\n", dev_num,
+ rew ? "non" : "auto", mode);
+ pr_err("st%d: Device not attached.\n", dev_num);
+ goto out_free;
+ }
+
+ i = mode << (4 - ST_NBR_MODE_BITS);
+ snprintf(name, 10, "%s%s%s", rew ? "n" : "",
+ tape->name, st_formats[i]);
+
+ dev = device_create(&st_sysfs_class, &tape->device->sdev_gendev,
+ cdev_devno, &tape->modes[mode], "%s", name);
+ if (IS_ERR(dev)) {
+ pr_err("st%d: device_create failed\n", dev_num);
+ error = PTR_ERR(dev);
+ goto out_free;
+ }
+
+ STm->devs[rew] = dev;
+
+ return 0;
+out_free:
+ cdev_del(STm->cdevs[rew]);
+out:
+ STm->cdevs[rew] = NULL;
+ STm->devs[rew] = NULL;
+ return error;
+}
+
+static int create_cdevs(struct scsi_tape *tape)
+{
+ int mode, error;
+ for (mode = 0; mode < ST_NBR_MODES; ++mode) {
+ error = create_one_cdev(tape, mode, 0);
+ if (error)
+ return error;
+ error = create_one_cdev(tape, mode, 1);
+ if (error)
+ return error;
+ }
+
+ return sysfs_create_link(&tape->device->sdev_gendev.kobj,
+ &tape->modes[0].devs[0]->kobj, "tape");
+}
+
+static void remove_cdevs(struct scsi_tape *tape)
+{
+ int mode, rew;
+ sysfs_remove_link(&tape->device->sdev_gendev.kobj, "tape");
+ for (mode = 0; mode < ST_NBR_MODES; mode++) {
+ struct st_modedef *STm = &(tape->modes[mode]);
+ for (rew = 0; rew < 2; rew++) {
+ if (STm->cdevs[rew])
+ cdev_del(STm->cdevs[rew]);
+ if (STm->devs[rew])
+ device_unregister(STm->devs[rew]);
+ }
+ }
+}
+
+static int st_probe(struct device *dev)
+{
+ struct scsi_device *SDp = to_scsi_device(dev);
+ struct scsi_tape *tpnt = NULL;
+ struct st_modedef *STm;
+ struct st_partstat *STps;
+ struct st_buffer *buffer;
+ int i, error;
+
+ if (SDp->type != TYPE_TAPE)
+ return -ENODEV;
+ if (st_incompatible(SDp)) {
+ sdev_printk(KERN_INFO, SDp,
+ "OnStream tapes are no longer supported;\n");
+ sdev_printk(KERN_INFO, SDp,
+ "please mail to linux-scsi@vger.kernel.org.\n");
+ return -ENODEV;
+ }
+
+ scsi_autopm_get_device(SDp);
+ i = queue_max_segments(SDp->request_queue);
+ if (st_max_sg_segs < i)
+ i = st_max_sg_segs;
+ buffer = new_tape_buffer(i);
+ if (buffer == NULL) {
+ sdev_printk(KERN_ERR, SDp,
+ "st: Can't allocate new tape buffer. "
+ "Device not attached.\n");
+ goto out;
+ }
+
+ tpnt = kzalloc(sizeof(struct scsi_tape), GFP_KERNEL);
+ if (tpnt == NULL) {
+ sdev_printk(KERN_ERR, SDp,
+ "st: Can't allocate device descriptor.\n");
+ goto out_buffer_free;
+ }
+ kref_init(&tpnt->kref);
+
+ tpnt->device = SDp;
+ if (SDp->scsi_level <= 2)
+ tpnt->tape_type = MT_ISSCSI1;
+ else
+ tpnt->tape_type = MT_ISSCSI2;
+
+ tpnt->buffer = buffer;
+ tpnt->buffer->last_SRpnt = NULL;
+
+ tpnt->inited = 0;
+ tpnt->dirty = 0;
+ tpnt->in_use = 0;
+ tpnt->drv_buffer = 1; /* Try buffering if no mode sense */
+ tpnt->use_pf = (SDp->scsi_level >= SCSI_2);
+ tpnt->density = 0;
+ tpnt->do_auto_lock = ST_AUTO_LOCK;
+ tpnt->can_bsr = (SDp->scsi_level > 2 ? 1 : ST_IN_FILE_POS); /* BSR mandatory in SCSI3 */
+ tpnt->can_partitions = 0;
+ tpnt->two_fm = ST_TWO_FM;
+ tpnt->fast_mteom = ST_FAST_MTEOM;
+ tpnt->scsi2_logical = ST_SCSI2LOGICAL;
+ tpnt->sili = ST_SILI;
+ tpnt->immediate = ST_NOWAIT;
+ tpnt->immediate_filemark = 0;
+ tpnt->default_drvbuffer = 0xff; /* No forced buffering */
+ tpnt->partition = 0;
+ tpnt->new_partition = 0;
+ tpnt->nbr_partitions = 0;
+ blk_queue_rq_timeout(tpnt->device->request_queue, ST_TIMEOUT);
+ tpnt->long_timeout = ST_LONG_TIMEOUT;
+ tpnt->try_dio = try_direct_io;
+
+ for (i = 0; i < ST_NBR_MODES; i++) {
+ STm = &(tpnt->modes[i]);
+ STm->defined = 0;
+ STm->sysv = ST_SYSV;
+ STm->defaults_for_writes = 0;
+ STm->do_async_writes = ST_ASYNC_WRITES;
+ STm->do_buffer_writes = ST_BUFFER_WRITES;
+ STm->do_read_ahead = ST_READ_AHEAD;
+ STm->default_compression = ST_DONT_TOUCH;
+ STm->default_blksize = (-1); /* No forced size */
+ STm->default_density = (-1); /* No forced density */
+ STm->tape = tpnt;
+ }
+
+ for (i = 0; i < ST_NBR_PARTITIONS; i++) {
+ STps = &(tpnt->ps[i]);
+ STps->rw = ST_IDLE;
+ STps->eof = ST_NOEOF;
+ STps->at_sm = 0;
+ STps->last_block_valid = 0;
+ STps->drv_block = (-1);
+ STps->drv_file = (-1);
+ }
+
+ tpnt->current_mode = 0;
+ tpnt->modes[0].defined = 1;
+
+ tpnt->density_changed = tpnt->compression_changed =
+ tpnt->blksize_changed = 0;
+ mutex_init(&tpnt->lock);
+
+ idr_preload(GFP_KERNEL);
+ spin_lock(&st_index_lock);
+ error = idr_alloc(&st_index_idr, tpnt, 0, ST_MAX_TAPES + 1, GFP_NOWAIT);
+ spin_unlock(&st_index_lock);
+ idr_preload_end();
+ if (error < 0) {
+ pr_warn("st: idr allocation failed: %d\n", error);
+ goto out_free_tape;
+ }
+ tpnt->index = error;
+ sprintf(tpnt->name, "st%d", tpnt->index);
+ tpnt->stats = kzalloc(sizeof(struct scsi_tape_stats), GFP_KERNEL);
+ if (tpnt->stats == NULL) {
+ sdev_printk(KERN_ERR, SDp,
+ "st: Can't allocate statistics.\n");
+ goto out_idr_remove;
+ }
+
+ dev_set_drvdata(dev, tpnt);
+
+
+ error = create_cdevs(tpnt);
+ if (error)
+ goto out_remove_devs;
+ scsi_autopm_put_device(SDp);
+
+ sdev_printk(KERN_NOTICE, SDp,
+ "Attached scsi tape %s\n", tpnt->name);
+ sdev_printk(KERN_INFO, SDp, "%s: try direct i/o: %s (alignment %d B)\n",
+ tpnt->name, tpnt->try_dio ? "yes" : "no",
+ queue_dma_alignment(SDp->request_queue) + 1);
+
+ return 0;
+
+out_remove_devs:
+ remove_cdevs(tpnt);
+ kfree(tpnt->stats);
+out_idr_remove:
+ spin_lock(&st_index_lock);
+ idr_remove(&st_index_idr, tpnt->index);
+ spin_unlock(&st_index_lock);
+out_free_tape:
+ kfree(tpnt);
+out_buffer_free:
+ kfree(buffer);
+out:
+ scsi_autopm_put_device(SDp);
+ return -ENODEV;
+};
+
+
+static int st_remove(struct device *dev)
+{
+ struct scsi_tape *tpnt = dev_get_drvdata(dev);
+ int index = tpnt->index;
+
+ scsi_autopm_get_device(to_scsi_device(dev));
+ remove_cdevs(tpnt);
+
+ mutex_lock(&st_ref_mutex);
+ kref_put(&tpnt->kref, scsi_tape_release);
+ mutex_unlock(&st_ref_mutex);
+ spin_lock(&st_index_lock);
+ idr_remove(&st_index_idr, index);
+ spin_unlock(&st_index_lock);
+ return 0;
+}
+
+/**
+ * scsi_tape_release - Called to free the Scsi_Tape structure
+ * @kref: pointer to embedded kref
+ *
+ * st_ref_mutex must be held entering this routine. Because it is
+ * called on last put, you should always use the scsi_tape_get()
+ * scsi_tape_put() helpers which manipulate the semaphore directly
+ * and never do a direct kref_put().
+ **/
+static void scsi_tape_release(struct kref *kref)
+{
+ struct scsi_tape *tpnt = to_scsi_tape(kref);
+
+ tpnt->device = NULL;
+
+ if (tpnt->buffer) {
+ normalize_buffer(tpnt->buffer);
+ kfree(tpnt->buffer->reserved_pages);
+ kfree(tpnt->buffer);
+ }
+
+ kfree(tpnt->stats);
+ kfree(tpnt);
+ return;
+}
+
+static struct class st_sysfs_class = {
+ .name = "scsi_tape",
+ .dev_groups = st_dev_groups,
+};
+
+static int __init init_st(void)
+{
+ int err;
+
+ validate_options();
+
+ printk(KERN_INFO "st: Version %s, fixed bufsize %d, s/g segs %d\n",
+ verstr, st_fixed_buffer_size, st_max_sg_segs);
+
+ debugging = (debug_flag > 0) ? debug_flag : NO_DEBUG;
+ if (debugging) {
+ printk(KERN_INFO "st: Debugging enabled debug_flag = %d\n",
+ debugging);
+ }
+
+ err = class_register(&st_sysfs_class);
+ if (err) {
+ pr_err("Unable register sysfs class for SCSI tapes\n");
+ return err;
+ }
+
+ err = register_chrdev_region(MKDEV(SCSI_TAPE_MAJOR, 0),
+ ST_MAX_TAPE_ENTRIES, "st");
+ if (err) {
+ printk(KERN_ERR "Unable to get major %d for SCSI tapes\n",
+ SCSI_TAPE_MAJOR);
+ goto err_class;
+ }
+
+ err = scsi_register_driver(&st_template.gendrv);
+ if (err)
+ goto err_chrdev;
+
+ return 0;
+
+err_chrdev:
+ unregister_chrdev_region(MKDEV(SCSI_TAPE_MAJOR, 0),
+ ST_MAX_TAPE_ENTRIES);
+err_class:
+ class_unregister(&st_sysfs_class);
+ return err;
+}
+
+static void __exit exit_st(void)
+{
+ scsi_unregister_driver(&st_template.gendrv);
+ unregister_chrdev_region(MKDEV(SCSI_TAPE_MAJOR, 0),
+ ST_MAX_TAPE_ENTRIES);
+ class_unregister(&st_sysfs_class);
+ idr_destroy(&st_index_idr);
+ printk(KERN_INFO "st: Unloaded.\n");
+}
+
+module_init(init_st);
+module_exit(exit_st);
+
+
+/* The sysfs driver interface. Read-only at the moment */
+static ssize_t try_direct_io_show(struct device_driver *ddp, char *buf)
+{
+ return scnprintf(buf, PAGE_SIZE, "%d\n", try_direct_io);
+}
+static DRIVER_ATTR_RO(try_direct_io);
+
+static ssize_t fixed_buffer_size_show(struct device_driver *ddp, char *buf)
+{
+ return scnprintf(buf, PAGE_SIZE, "%d\n", st_fixed_buffer_size);
+}
+static DRIVER_ATTR_RO(fixed_buffer_size);
+
+static ssize_t max_sg_segs_show(struct device_driver *ddp, char *buf)
+{
+ return scnprintf(buf, PAGE_SIZE, "%d\n", st_max_sg_segs);
+}
+static DRIVER_ATTR_RO(max_sg_segs);
+
+static ssize_t version_show(struct device_driver *ddd, char *buf)
+{
+ return scnprintf(buf, PAGE_SIZE, "[%s]\n", verstr);
+}
+static DRIVER_ATTR_RO(version);
+
+#if DEBUG
+static ssize_t debug_flag_store(struct device_driver *ddp,
+ const char *buf, size_t count)
+{
+/* We only care what the first byte of the data is the rest is unused.
+ * if it's a '1' we turn on debug and if it's a '0' we disable it. All
+ * other values have -EINVAL returned if they are passed in.
+ */
+ if (count > 0) {
+ if (buf[0] == '0') {
+ debugging = NO_DEBUG;
+ return count;
+ } else if (buf[0] == '1') {
+ debugging = 1;
+ return count;
+ }
+ }
+ return -EINVAL;
+}
+
+static ssize_t debug_flag_show(struct device_driver *ddp, char *buf)
+{
+ return scnprintf(buf, PAGE_SIZE, "%d\n", debugging);
+}
+static DRIVER_ATTR_RW(debug_flag);
+#endif
+
+static struct attribute *st_drv_attrs[] = {
+ &driver_attr_try_direct_io.attr,
+ &driver_attr_fixed_buffer_size.attr,
+ &driver_attr_max_sg_segs.attr,
+ &driver_attr_version.attr,
+#if DEBUG
+ &driver_attr_debug_flag.attr,
+#endif
+ NULL,
+};
+ATTRIBUTE_GROUPS(st_drv);
+
+/* The sysfs simple class interface */
+static ssize_t
+defined_show(struct device *dev, struct device_attribute *attr, char *buf)
+{
+ struct st_modedef *STm = dev_get_drvdata(dev);
+ ssize_t l = 0;
+
+ l = snprintf(buf, PAGE_SIZE, "%d\n", STm->defined);
+ return l;
+}
+static DEVICE_ATTR_RO(defined);
+
+static ssize_t
+default_blksize_show(struct device *dev, struct device_attribute *attr,
+ char *buf)
+{
+ struct st_modedef *STm = dev_get_drvdata(dev);
+ ssize_t l = 0;
+
+ l = snprintf(buf, PAGE_SIZE, "%d\n", STm->default_blksize);
+ return l;
+}
+static DEVICE_ATTR_RO(default_blksize);
+
+static ssize_t
+default_density_show(struct device *dev, struct device_attribute *attr,
+ char *buf)
+{
+ struct st_modedef *STm = dev_get_drvdata(dev);
+ ssize_t l = 0;
+ char *fmt;
+
+ fmt = STm->default_density >= 0 ? "0x%02x\n" : "%d\n";
+ l = snprintf(buf, PAGE_SIZE, fmt, STm->default_density);
+ return l;
+}
+static DEVICE_ATTR_RO(default_density);
+
+static ssize_t
+default_compression_show(struct device *dev, struct device_attribute *attr,
+ char *buf)
+{
+ struct st_modedef *STm = dev_get_drvdata(dev);
+ ssize_t l = 0;
+
+ l = snprintf(buf, PAGE_SIZE, "%d\n", STm->default_compression - 1);
+ return l;
+}
+static DEVICE_ATTR_RO(default_compression);
+
+static ssize_t
+options_show(struct device *dev, struct device_attribute *attr, char *buf)
+{
+ struct st_modedef *STm = dev_get_drvdata(dev);
+ struct scsi_tape *STp = STm->tape;
+ int options;
+ ssize_t l = 0;
+
+ options = STm->do_buffer_writes ? MT_ST_BUFFER_WRITES : 0;
+ options |= STm->do_async_writes ? MT_ST_ASYNC_WRITES : 0;
+ options |= STm->do_read_ahead ? MT_ST_READ_AHEAD : 0;
+ DEB( options |= debugging ? MT_ST_DEBUGGING : 0 );
+ options |= STp->two_fm ? MT_ST_TWO_FM : 0;
+ options |= STp->fast_mteom ? MT_ST_FAST_MTEOM : 0;
+ options |= STm->defaults_for_writes ? MT_ST_DEF_WRITES : 0;
+ options |= STp->can_bsr ? MT_ST_CAN_BSR : 0;
+ options |= STp->omit_blklims ? MT_ST_NO_BLKLIMS : 0;
+ options |= STp->can_partitions ? MT_ST_CAN_PARTITIONS : 0;
+ options |= STp->scsi2_logical ? MT_ST_SCSI2LOGICAL : 0;
+ options |= STm->sysv ? MT_ST_SYSV : 0;
+ options |= STp->immediate ? MT_ST_NOWAIT : 0;
+ options |= STp->immediate_filemark ? MT_ST_NOWAIT_EOF : 0;
+ options |= STp->sili ? MT_ST_SILI : 0;
+
+ l = snprintf(buf, PAGE_SIZE, "0x%08x\n", options);
+ return l;
+}
+static DEVICE_ATTR_RO(options);
+
+/* Support for tape stats */
+
+/**
+ * read_cnt_show - return read count - count of reads made from tape drive
+ * @dev: struct device
+ * @attr: attribute structure
+ * @buf: buffer to return formatted data in
+ */
+static ssize_t read_cnt_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct st_modedef *STm = dev_get_drvdata(dev);
+
+ return sprintf(buf, "%lld",
+ (long long)atomic64_read(&STm->tape->stats->read_cnt));
+}
+static DEVICE_ATTR_RO(read_cnt);
+
+/**
+ * read_byte_cnt_show - return read byte count - tape drives
+ * may use blocks less than 512 bytes this gives the raw byte count of
+ * of data read from the tape drive.
+ * @dev: struct device
+ * @attr: attribute structure
+ * @buf: buffer to return formatted data in
+ */
+static ssize_t read_byte_cnt_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct st_modedef *STm = dev_get_drvdata(dev);
+
+ return sprintf(buf, "%lld",
+ (long long)atomic64_read(&STm->tape->stats->read_byte_cnt));
+}
+static DEVICE_ATTR_RO(read_byte_cnt);
+
+/**
+ * read_ns_show - return read ns - overall time spent waiting on reads in ns.
+ * @dev: struct device
+ * @attr: attribute structure
+ * @buf: buffer to return formatted data in
+ */
+static ssize_t read_ns_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct st_modedef *STm = dev_get_drvdata(dev);
+
+ return sprintf(buf, "%lld",
+ (long long)atomic64_read(&STm->tape->stats->tot_read_time));
+}
+static DEVICE_ATTR_RO(read_ns);
+
+/**
+ * write_cnt_show - write count - number of user calls
+ * to write(2) that have written data to tape.
+ * @dev: struct device
+ * @attr: attribute structure
+ * @buf: buffer to return formatted data in
+ */
+static ssize_t write_cnt_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct st_modedef *STm = dev_get_drvdata(dev);
+
+ return sprintf(buf, "%lld",
+ (long long)atomic64_read(&STm->tape->stats->write_cnt));
+}
+static DEVICE_ATTR_RO(write_cnt);
+
+/**
+ * write_byte_cnt_show - write byte count - raw count of
+ * bytes written to tape.
+ * @dev: struct device
+ * @attr: attribute structure
+ * @buf: buffer to return formatted data in
+ */
+static ssize_t write_byte_cnt_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct st_modedef *STm = dev_get_drvdata(dev);
+
+ return sprintf(buf, "%lld",
+ (long long)atomic64_read(&STm->tape->stats->write_byte_cnt));
+}
+static DEVICE_ATTR_RO(write_byte_cnt);
+
+/**
+ * write_ns_show - write ns - number of nanoseconds waiting on write
+ * requests to complete.
+ * @dev: struct device
+ * @attr: attribute structure
+ * @buf: buffer to return formatted data in
+ */
+static ssize_t write_ns_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct st_modedef *STm = dev_get_drvdata(dev);
+
+ return sprintf(buf, "%lld",
+ (long long)atomic64_read(&STm->tape->stats->tot_write_time));
+}
+static DEVICE_ATTR_RO(write_ns);
+
+/**
+ * in_flight_show - number of I/Os currently in flight -
+ * in most cases this will be either 0 or 1. It may be higher if someone
+ * has also issued other SCSI commands such as via an ioctl.
+ * @dev: struct device
+ * @attr: attribute structure
+ * @buf: buffer to return formatted data in
+ */
+static ssize_t in_flight_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct st_modedef *STm = dev_get_drvdata(dev);
+
+ return sprintf(buf, "%lld",
+ (long long)atomic64_read(&STm->tape->stats->in_flight));
+}
+static DEVICE_ATTR_RO(in_flight);
+
+/**
+ * io_ns_show - io wait ns - this is the number of ns spent
+ * waiting on all I/O to complete. This includes tape movement commands
+ * such as rewinding, seeking to end of file or tape, it also includes
+ * read and write. To determine the time spent on tape movement
+ * subtract the read and write ns from this value.
+ * @dev: struct device
+ * @attr: attribute structure
+ * @buf: buffer to return formatted data in
+ */
+static ssize_t io_ns_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct st_modedef *STm = dev_get_drvdata(dev);
+
+ return sprintf(buf, "%lld",
+ (long long)atomic64_read(&STm->tape->stats->tot_io_time));
+}
+static DEVICE_ATTR_RO(io_ns);
+
+/**
+ * other_cnt_show - other io count - this is the number of
+ * I/O requests other than read and write requests.
+ * Typically these are tape movement requests but will include driver
+ * tape movement. This includes only requests issued by the st driver.
+ * @dev: struct device
+ * @attr: attribute structure
+ * @buf: buffer to return formatted data in
+ */
+static ssize_t other_cnt_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct st_modedef *STm = dev_get_drvdata(dev);
+
+ return sprintf(buf, "%lld",
+ (long long)atomic64_read(&STm->tape->stats->other_cnt));
+}
+static DEVICE_ATTR_RO(other_cnt);
+
+/**
+ * resid_cnt_show - A count of the number of times we get a residual
+ * count - this should indicate someone issuing reads larger than the
+ * block size on tape.
+ * @dev: struct device
+ * @attr: attribute structure
+ * @buf: buffer to return formatted data in
+ */
+static ssize_t resid_cnt_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct st_modedef *STm = dev_get_drvdata(dev);
+
+ return sprintf(buf, "%lld",
+ (long long)atomic64_read(&STm->tape->stats->resid_cnt));
+}
+static DEVICE_ATTR_RO(resid_cnt);
+
+static struct attribute *st_dev_attrs[] = {
+ &dev_attr_defined.attr,
+ &dev_attr_default_blksize.attr,
+ &dev_attr_default_density.attr,
+ &dev_attr_default_compression.attr,
+ &dev_attr_options.attr,
+ NULL,
+};
+
+static struct attribute *st_stats_attrs[] = {
+ &dev_attr_read_cnt.attr,
+ &dev_attr_read_byte_cnt.attr,
+ &dev_attr_read_ns.attr,
+ &dev_attr_write_cnt.attr,
+ &dev_attr_write_byte_cnt.attr,
+ &dev_attr_write_ns.attr,
+ &dev_attr_in_flight.attr,
+ &dev_attr_io_ns.attr,
+ &dev_attr_other_cnt.attr,
+ &dev_attr_resid_cnt.attr,
+ NULL,
+};
+
+static struct attribute_group stats_group = {
+ .name = "stats",
+ .attrs = st_stats_attrs,
+};
+
+static struct attribute_group st_group = {
+ .attrs = st_dev_attrs,
+};
+
+static const struct attribute_group *st_dev_groups[] = {
+ &st_group,
+ &stats_group,
+ NULL,
+};
+
+/* The following functions may be useful for a larger audience. */
+static int sgl_map_user_pages(struct st_buffer *STbp,
+ const unsigned int max_pages, unsigned long uaddr,
+ size_t count, int rw)
+{
+ unsigned long end = (uaddr + count + PAGE_SIZE - 1) >> PAGE_SHIFT;
+ unsigned long start = uaddr >> PAGE_SHIFT;
+ const int nr_pages = end - start;
+ int res, i;
+ struct page **pages;
+ struct rq_map_data *mdata = &STbp->map_data;
+
+ /* User attempted Overflow! */
+ if ((uaddr + count) < uaddr)
+ return -EINVAL;
+
+ /* Too big */
+ if (nr_pages > max_pages)
+ return -ENOMEM;
+
+ /* Hmm? */
+ if (count == 0)
+ return 0;
+
+ pages = kmalloc_array(max_pages, sizeof(*pages), GFP_KERNEL);
+ if (pages == NULL)
+ return -ENOMEM;
+
+ /* Try to fault in all of the necessary pages */
+ /* rw==READ means read from drive, write into memory area */
+ res = pin_user_pages_fast(uaddr, nr_pages, rw == READ ? FOLL_WRITE : 0,
+ pages);
+
+ /* Errors and no page mapped should return here */
+ if (res < nr_pages)
+ goto out_unmap;
+
+ for (i=0; i < nr_pages; i++) {
+ /* FIXME: flush superflous for rw==READ,
+ * probably wrong function for rw==WRITE
+ */
+ flush_dcache_page(pages[i]);
+ }
+
+ mdata->offset = uaddr & ~PAGE_MASK;
+ STbp->mapped_pages = pages;
+
+ return nr_pages;
+ out_unmap:
+ if (res > 0) {
+ unpin_user_pages(pages, res);
+ res = 0;
+ }
+ kfree(pages);
+ return res;
+}
+
+
+/* And unmap them... */
+static int sgl_unmap_user_pages(struct st_buffer *STbp,
+ const unsigned int nr_pages, int dirtied)
+{
+ /* FIXME: cache flush missing for rw==READ */
+ unpin_user_pages_dirty_lock(STbp->mapped_pages, nr_pages, dirtied);
+
+ kfree(STbp->mapped_pages);
+ STbp->mapped_pages = NULL;
+
+ return 0;
+}