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kernel/drivers/ide/ide-tape.c
Christoph Hellwig 22ce0a7ccf ide: don't use req->special 
Just replace it with a field of the same name in struct ide_req.

Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-11-10 08:03:52 -07:00

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/*
* IDE ATAPI streaming tape driver.
*
* Copyright (C) 1995-1999 Gadi Oxman <gadio@netvision.net.il>
* Copyright (C) 2003-2005 Bartlomiej Zolnierkiewicz
*
* This driver was constructed as a student project in the software laboratory
* of the faculty of electrical engineering in the Technion - Israel's
* Institute Of Technology, with the guide of Avner Lottem and Dr. Ilana David.
*
* It is hereby placed under the terms of the GNU general public license.
* (See linux/COPYING).
*
* For a historical changelog see
* Documentation/ide/ChangeLog.ide-tape.1995-2002
*/
#define DRV_NAME "ide-tape"
#define IDETAPE_VERSION "1.20"
#include <linux/module.h>
#include <linux/types.h>
#include <linux/string.h>
#include <linux/kernel.h>
#include <linux/delay.h>
#include <linux/timer.h>
#include <linux/mm.h>
#include <linux/interrupt.h>
#include <linux/jiffies.h>
#include <linux/major.h>
#include <linux/errno.h>
#include <linux/genhd.h>
#include <linux/seq_file.h>
#include <linux/slab.h>
#include <linux/pci.h>
#include <linux/ide.h>
#include <linux/completion.h>
#include <linux/bitops.h>
#include <linux/mutex.h>
#include <scsi/scsi.h>
#include <asm/byteorder.h>
#include <linux/uaccess.h>
#include <linux/io.h>
#include <asm/unaligned.h>
#include <linux/mtio.h>
/* define to see debug info */
#undef IDETAPE_DEBUG_LOG
#ifdef IDETAPE_DEBUG_LOG
#define ide_debug_log(lvl, fmt, args...) __ide_debug_log(lvl, fmt, ## args)
#else
#define ide_debug_log(lvl, fmt, args...) do {} while (0)
#endif
/**************************** Tunable parameters *****************************/
/*
* After each failed packet command we issue a request sense command and retry
* the packet command IDETAPE_MAX_PC_RETRIES times.
*
* Setting IDETAPE_MAX_PC_RETRIES to 0 will disable retries.
*/
#define IDETAPE_MAX_PC_RETRIES 3
/*
* The following parameter is used to select the point in the internal tape fifo
* in which we will start to refill the buffer. Decreasing the following
* parameter will improve the system's latency and interactive response, while
* using a high value might improve system throughput.
*/
#define IDETAPE_FIFO_THRESHOLD 2
/*
* DSC polling parameters.
*
* Polling for DSC (a single bit in the status register) is a very important
* function in ide-tape. There are two cases in which we poll for DSC:
*
* 1. Before a read/write packet command, to ensure that we can transfer data
* from/to the tape's data buffers, without causing an actual media access.
* In case the tape is not ready yet, we take out our request from the device
* request queue, so that ide.c could service requests from the other device
* on the same interface in the meantime.
*
* 2. After the successful initialization of a "media access packet command",
* which is a command that can take a long time to complete (the interval can
* range from several seconds to even an hour). Again, we postpone our request
* in the middle to free the bus for the other device. The polling frequency
* here should be lower than the read/write frequency since those media access
* commands are slow. We start from a "fast" frequency - IDETAPE_DSC_MA_FAST
* (1 second), and if we don't receive DSC after IDETAPE_DSC_MA_THRESHOLD
* (5 min), we switch it to a lower frequency - IDETAPE_DSC_MA_SLOW (1 min).
*
* We also set a timeout for the timer, in case something goes wrong. The
* timeout should be longer then the maximum execution time of a tape operation.
*/
/* DSC timings. */
#define IDETAPE_DSC_RW_MIN 5*HZ/100 /* 50 msec */
#define IDETAPE_DSC_RW_MAX 40*HZ/100 /* 400 msec */
#define IDETAPE_DSC_RW_TIMEOUT 2*60*HZ /* 2 minutes */
#define IDETAPE_DSC_MA_FAST 2*HZ /* 2 seconds */
#define IDETAPE_DSC_MA_THRESHOLD 5*60*HZ /* 5 minutes */
#define IDETAPE_DSC_MA_SLOW 30*HZ /* 30 seconds */
#define IDETAPE_DSC_MA_TIMEOUT 2*60*60*HZ /* 2 hours */
/*************************** End of tunable parameters ***********************/
/* tape directions */
enum {
IDETAPE_DIR_NONE = (1 << 0),
IDETAPE_DIR_READ = (1 << 1),
IDETAPE_DIR_WRITE = (1 << 2),
};
/* Tape door status */
#define DOOR_UNLOCKED 0
#define DOOR_LOCKED 1
#define DOOR_EXPLICITLY_LOCKED 2
/* Some defines for the SPACE command */
#define IDETAPE_SPACE_OVER_FILEMARK 1
#define IDETAPE_SPACE_TO_EOD 3
/* Some defines for the LOAD UNLOAD command */
#define IDETAPE_LU_LOAD_MASK 1
#define IDETAPE_LU_RETENSION_MASK 2
#define IDETAPE_LU_EOT_MASK 4
/* Structures related to the SELECT SENSE / MODE SENSE packet commands. */
#define IDETAPE_BLOCK_DESCRIPTOR 0
#define IDETAPE_CAPABILITIES_PAGE 0x2a
/*
* Most of our global data which we need to save even as we leave the driver due
* to an interrupt or a timer event is stored in the struct defined below.
*/
typedef struct ide_tape_obj {
ide_drive_t *drive;
struct ide_driver *driver;
struct gendisk *disk;
struct device dev;
/* used by REQ_IDETAPE_{READ,WRITE} requests */
struct ide_atapi_pc queued_pc;
/*
* DSC polling variables.
*
* While polling for DSC we use postponed_rq to postpone the current
* request so that ide.c will be able to service pending requests on the
* other device. Note that at most we will have only one DSC (usually
* data transfer) request in the device request queue.
*/
bool postponed_rq;
/* The time in which we started polling for DSC */
unsigned long dsc_polling_start;
/* Timer used to poll for dsc */
struct timer_list dsc_timer;
/* Read/Write dsc polling frequency */
unsigned long best_dsc_rw_freq;
unsigned long dsc_poll_freq;
unsigned long dsc_timeout;
/* Read position information */
u8 partition;
/* Current block */
unsigned int first_frame;
/* Last error information */
u8 sense_key, asc, ascq;
/* Character device operation */
unsigned int minor;
/* device name */
char name[4];
/* Current character device data transfer direction */
u8 chrdev_dir;
/* tape block size, usually 512 or 1024 bytes */
unsigned short blk_size;
int user_bs_factor;
/* Copy of the tape's Capabilities and Mechanical Page */
u8 caps[20];
/*
* Active data transfer request parameters.
*
* At most, there is only one ide-tape originated data transfer request
* in the device request queue. This allows ide.c to easily service
* requests from the other device when we postpone our active request.
*/
/* Data buffer size chosen based on the tape's recommendation */
int buffer_size;
/* Staging buffer of buffer_size bytes */
void *buf;
/* The read/write cursor */
void *cur;
/* The number of valid bytes in buf */
size_t valid;
/* Measures average tape speed */
unsigned long avg_time;
int avg_size;
int avg_speed;
/* the door is currently locked */
int door_locked;
/* the tape hardware is write protected */
char drv_write_prot;
/* the tape is write protected (hardware or opened as read-only) */
char write_prot;
} idetape_tape_t;
static DEFINE_MUTEX(ide_tape_mutex);
static DEFINE_MUTEX(idetape_ref_mutex);
static DEFINE_MUTEX(idetape_chrdev_mutex);
static struct class *idetape_sysfs_class;
static void ide_tape_release(struct device *);
static struct ide_tape_obj *idetape_devs[MAX_HWIFS * MAX_DRIVES];
static struct ide_tape_obj *ide_tape_get(struct gendisk *disk, bool cdev,
unsigned int i)
{
struct ide_tape_obj *tape = NULL;
mutex_lock(&idetape_ref_mutex);
if (cdev)
tape = idetape_devs[i];
else
tape = ide_drv_g(disk, ide_tape_obj);
if (tape) {
if (ide_device_get(tape->drive))
tape = NULL;
else
get_device(&tape->dev);
}
mutex_unlock(&idetape_ref_mutex);
return tape;
}
static void ide_tape_put(struct ide_tape_obj *tape)
{
ide_drive_t *drive = tape->drive;
mutex_lock(&idetape_ref_mutex);
put_device(&tape->dev);
ide_device_put(drive);
mutex_unlock(&idetape_ref_mutex);
}
/*
* called on each failed packet command retry to analyze the request sense. We
* currently do not utilize this information.
*/
static void idetape_analyze_error(ide_drive_t *drive)
{
idetape_tape_t *tape = drive->driver_data;
struct ide_atapi_pc *pc = drive->failed_pc;
struct request *rq = drive->hwif->rq;
u8 *sense = bio_data(rq->bio);
tape->sense_key = sense[2] & 0xF;
tape->asc = sense[12];
tape->ascq = sense[13];
ide_debug_log(IDE_DBG_FUNC,
"cmd: 0x%x, sense key = %x, asc = %x, ascq = %x",
rq->cmd[0], tape->sense_key, tape->asc, tape->ascq);
/* correct remaining bytes to transfer */
if (pc->flags & PC_FLAG_DMA_ERROR)
scsi_req(rq)->resid_len = tape->blk_size * get_unaligned_be32(&sense[3]);
/*
* If error was the result of a zero-length read or write command,
* with sense key=5, asc=0x22, ascq=0, let it slide. Some drives
* (i.e. Seagate STT3401A Travan) don't support 0-length read/writes.
*/
if ((pc->c[0] == READ_6 || pc->c[0] == WRITE_6)
/* length == 0 */
&& pc->c[4] == 0 && pc->c[3] == 0 && pc->c[2] == 0) {
if (tape->sense_key == 5) {
/* don't report an error, everything's ok */
pc->error = 0;
/* don't retry read/write */
pc->flags |= PC_FLAG_ABORT;
}
}
if (pc->c[0] == READ_6 && (sense[2] & 0x80)) {
pc->error = IDE_DRV_ERROR_FILEMARK;
pc->flags |= PC_FLAG_ABORT;
}
if (pc->c[0] == WRITE_6) {
if ((sense[2] & 0x40) || (tape->sense_key == 0xd
&& tape->asc == 0x0 && tape->ascq == 0x2)) {
pc->error = IDE_DRV_ERROR_EOD;
pc->flags |= PC_FLAG_ABORT;
}
}
if (pc->c[0] == READ_6 || pc->c[0] == WRITE_6) {
if (tape->sense_key == 8) {
pc->error = IDE_DRV_ERROR_EOD;
pc->flags |= PC_FLAG_ABORT;
}
if (!(pc->flags & PC_FLAG_ABORT) &&
(blk_rq_bytes(rq) - scsi_req(rq)->resid_len))
pc->retries = IDETAPE_MAX_PC_RETRIES + 1;
}
}
static void ide_tape_handle_dsc(ide_drive_t *);
static int ide_tape_callback(ide_drive_t *drive, int dsc)
{
idetape_tape_t *tape = drive->driver_data;
struct ide_atapi_pc *pc = drive->pc;
struct request *rq = drive->hwif->rq;
int uptodate = pc->error ? 0 : 1;
int err = uptodate ? 0 : IDE_DRV_ERROR_GENERAL;
ide_debug_log(IDE_DBG_FUNC, "cmd: 0x%x, dsc: %d, err: %d", rq->cmd[0],
dsc, err);
if (dsc)
ide_tape_handle_dsc(drive);
if (drive->failed_pc == pc)
drive->failed_pc = NULL;
if (pc->c[0] == REQUEST_SENSE) {
if (uptodate)
idetape_analyze_error(drive);
else
printk(KERN_ERR "ide-tape: Error in REQUEST SENSE "
"itself - Aborting request!\n");
} else if (pc->c[0] == READ_6 || pc->c[0] == WRITE_6) {
unsigned int blocks =
(blk_rq_bytes(rq) - scsi_req(rq)->resid_len) / tape->blk_size;
tape->avg_size += blocks * tape->blk_size;
if (time_after_eq(jiffies, tape->avg_time + HZ)) {
tape->avg_speed = tape->avg_size * HZ /
(jiffies - tape->avg_time) / 1024;
tape->avg_size = 0;
tape->avg_time = jiffies;
}
tape->first_frame += blocks;
if (pc->error) {
uptodate = 0;
err = pc->error;
}
}
scsi_req(rq)->result = err;
return uptodate;
}
/*
* Postpone the current request so that ide.c will be able to service requests
* from another device on the same port while we are polling for DSC.
*/
static void ide_tape_stall_queue(ide_drive_t *drive)
{
idetape_tape_t *tape = drive->driver_data;
ide_debug_log(IDE_DBG_FUNC, "cmd: 0x%x, dsc_poll_freq: %lu",
drive->hwif->rq->cmd[0], tape->dsc_poll_freq);
tape->postponed_rq = true;
ide_stall_queue(drive, tape->dsc_poll_freq);
}
static void ide_tape_handle_dsc(ide_drive_t *drive)
{
idetape_tape_t *tape = drive->driver_data;
/* Media access command */
tape->dsc_polling_start = jiffies;
tape->dsc_poll_freq = IDETAPE_DSC_MA_FAST;
tape->dsc_timeout = jiffies + IDETAPE_DSC_MA_TIMEOUT;
/* Allow ide.c to handle other requests */
ide_tape_stall_queue(drive);
}
/*
* Packet Command Interface
*
* The current Packet Command is available in drive->pc, and will not change
* until we finish handling it. Each packet command is associated with a
* callback function that will be called when the command is finished.
*
* The handling will be done in three stages:
*
* 1. ide_tape_issue_pc will send the packet command to the drive, and will set
* the interrupt handler to ide_pc_intr.
*
* 2. On each interrupt, ide_pc_intr will be called. This step will be
* repeated until the device signals us that no more interrupts will be issued.
*
* 3. ATAPI Tape media access commands have immediate status with a delayed
* process. In case of a successful initiation of a media access packet command,
* the DSC bit will be set when the actual execution of the command is finished.
* Since the tape drive will not issue an interrupt, we have to poll for this
* event. In this case, we define the request as "low priority request" by
* setting rq_status to IDETAPE_RQ_POSTPONED, set a timer to poll for DSC and
* exit the driver.
*
* ide.c will then give higher priority to requests which originate from the
* other device, until will change rq_status to RQ_ACTIVE.
*
* 4. When the packet command is finished, it will be checked for errors.
*
* 5. In case an error was found, we queue a request sense packet command in
* front of the request queue and retry the operation up to
* IDETAPE_MAX_PC_RETRIES times.
*
* 6. In case no error was found, or we decided to give up and not to retry
* again, the callback function will be called and then we will handle the next
* request.
*/
static ide_startstop_t ide_tape_issue_pc(ide_drive_t *drive,
struct ide_cmd *cmd,
struct ide_atapi_pc *pc)
{
idetape_tape_t *tape = drive->driver_data;
struct request *rq = drive->hwif->rq;
if (drive->failed_pc == NULL && pc->c[0] != REQUEST_SENSE)
drive->failed_pc = pc;
/* Set the current packet command */
drive->pc = pc;
if (pc->retries > IDETAPE_MAX_PC_RETRIES ||
(pc->flags & PC_FLAG_ABORT)) {
/*
* We will "abort" retrying a packet command in case legitimate
* error code was received (crossing a filemark, or end of the
* media, for example).
*/
if (!(pc->flags & PC_FLAG_ABORT)) {
if (!(pc->c[0] == TEST_UNIT_READY &&
tape->sense_key == 2 && tape->asc == 4 &&
(tape->ascq == 1 || tape->ascq == 8))) {
printk(KERN_ERR "ide-tape: %s: I/O error, "
"pc = %2x, key = %2x, "
"asc = %2x, ascq = %2x\n",
tape->name, pc->c[0],
tape->sense_key, tape->asc,
tape->ascq);
}
/* Giving up */
pc->error = IDE_DRV_ERROR_GENERAL;
}
drive->failed_pc = NULL;
drive->pc_callback(drive, 0);
ide_complete_rq(drive, BLK_STS_IOERR, blk_rq_bytes(rq));
return ide_stopped;
}
ide_debug_log(IDE_DBG_SENSE, "retry #%d, cmd: 0x%02x", pc->retries,
pc->c[0]);
pc->retries++;
return ide_issue_pc(drive, cmd);
}
/* A mode sense command is used to "sense" tape parameters. */
static void idetape_create_mode_sense_cmd(struct ide_atapi_pc *pc, u8 page_code)
{
ide_init_pc(pc);
pc->c[0] = MODE_SENSE;
if (page_code != IDETAPE_BLOCK_DESCRIPTOR)
/* DBD = 1 - Don't return block descriptors */
pc->c[1] = 8;
pc->c[2] = page_code;
/*
* Changed pc->c[3] to 0 (255 will at best return unused info).
*
* For SCSI this byte is defined as subpage instead of high byte
* of length and some IDE drives seem to interpret it this way
* and return an error when 255 is used.
*/
pc->c[3] = 0;
/* We will just discard data in that case */
pc->c[4] = 255;
if (page_code == IDETAPE_BLOCK_DESCRIPTOR)
pc->req_xfer = 12;
else if (page_code == IDETAPE_CAPABILITIES_PAGE)
pc->req_xfer = 24;
else
pc->req_xfer = 50;
}
static ide_startstop_t idetape_media_access_finished(ide_drive_t *drive)
{
ide_hwif_t *hwif = drive->hwif;
idetape_tape_t *tape = drive->driver_data;
struct ide_atapi_pc *pc = drive->pc;
u8 stat;
stat = hwif->tp_ops->read_status(hwif);
if (stat & ATA_DSC) {
if (stat & ATA_ERR) {
/* Error detected */
if (pc->c[0] != TEST_UNIT_READY)
printk(KERN_ERR "ide-tape: %s: I/O error, ",
tape->name);
/* Retry operation */
ide_retry_pc(drive);
return ide_stopped;
}
pc->error = 0;
} else {
pc->error = IDE_DRV_ERROR_GENERAL;
drive->failed_pc = NULL;
}
drive->pc_callback(drive, 0);
return ide_stopped;
}
static void ide_tape_create_rw_cmd(idetape_tape_t *tape,
struct ide_atapi_pc *pc, struct request *rq,
u8 opcode)
{
unsigned int length = blk_rq_sectors(rq) / (tape->blk_size >> 9);
ide_init_pc(pc);
put_unaligned(cpu_to_be32(length), (unsigned int *) &pc->c[1]);
pc->c[1] = 1;
if (blk_rq_bytes(rq) == tape->buffer_size)
pc->flags |= PC_FLAG_DMA_OK;
if (opcode == READ_6)
pc->c[0] = READ_6;
else if (opcode == WRITE_6) {
pc->c[0] = WRITE_6;
pc->flags |= PC_FLAG_WRITING;
}
memcpy(scsi_req(rq)->cmd, pc->c, 12);
}
static ide_startstop_t idetape_do_request(ide_drive_t *drive,
struct request *rq, sector_t block)
{
ide_hwif_t *hwif = drive->hwif;
idetape_tape_t *tape = drive->driver_data;
struct ide_atapi_pc *pc = NULL;
struct ide_cmd cmd;
struct scsi_request *req = scsi_req(rq);
u8 stat;
ide_debug_log(IDE_DBG_RQ, "cmd: 0x%x, sector: %llu, nr_sectors: %u",
req->cmd[0], (unsigned long long)blk_rq_pos(rq),
blk_rq_sectors(rq));
BUG_ON(!blk_rq_is_private(rq));
BUG_ON(ide_req(rq)->type != ATA_PRIV_MISC &&
ide_req(rq)->type != ATA_PRIV_SENSE);
/* Retry a failed packet command */
if (drive->failed_pc && drive->pc->c[0] == REQUEST_SENSE) {
pc = drive->failed_pc;
goto out;
}
/*
* If the tape is still busy, postpone our request and service
* the other device meanwhile.
*/
stat = hwif->tp_ops->read_status(hwif);
if ((drive->dev_flags & IDE_DFLAG_DSC_OVERLAP) == 0 &&
(req->cmd[13] & REQ_IDETAPE_PC2) == 0)
drive->atapi_flags |= IDE_AFLAG_IGNORE_DSC;
if (drive->dev_flags & IDE_DFLAG_POST_RESET) {
drive->atapi_flags |= IDE_AFLAG_IGNORE_DSC;
drive->dev_flags &= ~IDE_DFLAG_POST_RESET;
}
if (!(drive->atapi_flags & IDE_AFLAG_IGNORE_DSC) &&
!(stat & ATA_DSC)) {
if (!tape->postponed_rq) {
tape->dsc_polling_start = jiffies;
tape->dsc_poll_freq = tape->best_dsc_rw_freq;
tape->dsc_timeout = jiffies + IDETAPE_DSC_RW_TIMEOUT;
} else if (time_after(jiffies, tape->dsc_timeout)) {
printk(KERN_ERR "ide-tape: %s: DSC timeout\n",
tape->name);
if (req->cmd[13] & REQ_IDETAPE_PC2) {
idetape_media_access_finished(drive);
return ide_stopped;
} else {
return ide_do_reset(drive);
}
} else if (time_after(jiffies,
tape->dsc_polling_start +
IDETAPE_DSC_MA_THRESHOLD))
tape->dsc_poll_freq = IDETAPE_DSC_MA_SLOW;
ide_tape_stall_queue(drive);
return ide_stopped;
} else {
drive->atapi_flags &= ~IDE_AFLAG_IGNORE_DSC;
tape->postponed_rq = false;
}
if (req->cmd[13] & REQ_IDETAPE_READ) {
pc = &tape->queued_pc;
ide_tape_create_rw_cmd(tape, pc, rq, READ_6);
goto out;
}
if (req->cmd[13] & REQ_IDETAPE_WRITE) {
pc = &tape->queued_pc;
ide_tape_create_rw_cmd(tape, pc, rq, WRITE_6);
goto out;
}
if (req->cmd[13] & REQ_IDETAPE_PC1) {
pc = (struct ide_atapi_pc *)ide_req(rq)->special;
req->cmd[13] &= ~(REQ_IDETAPE_PC1);
req->cmd[13] |= REQ_IDETAPE_PC2;
goto out;
}
if (req->cmd[13] & REQ_IDETAPE_PC2) {
idetape_media_access_finished(drive);
return ide_stopped;
}
BUG();
out:
/* prepare sense request for this command */
ide_prep_sense(drive, rq);
memset(&cmd, 0, sizeof(cmd));
if (rq_data_dir(rq))
cmd.tf_flags |= IDE_TFLAG_WRITE;
cmd.rq = rq;
ide_init_sg_cmd(&cmd, blk_rq_bytes(rq));
ide_map_sg(drive, &cmd);
return ide_tape_issue_pc(drive, &cmd, pc);
}
/*
* Write a filemark if write_filemark=1. Flush the device buffers without
* writing a filemark otherwise.
*/
static void idetape_create_write_filemark_cmd(ide_drive_t *drive,
struct ide_atapi_pc *pc, int write_filemark)
{
ide_init_pc(pc);
pc->c[0] = WRITE_FILEMARKS;
pc->c[4] = write_filemark;
pc->flags |= PC_FLAG_WAIT_FOR_DSC;
}
static int idetape_wait_ready(ide_drive_t *drive, unsigned long timeout)
{
idetape_tape_t *tape = drive->driver_data;
struct gendisk *disk = tape->disk;
int load_attempted = 0;
/* Wait for the tape to become ready */
set_bit(ilog2(IDE_AFLAG_MEDIUM_PRESENT), &drive->atapi_flags);
timeout += jiffies;
while (time_before(jiffies, timeout)) {
if (ide_do_test_unit_ready(drive, disk) == 0)
return 0;
if ((tape->sense_key == 2 && tape->asc == 4 && tape->ascq == 2)
|| (tape->asc == 0x3A)) {
/* no media */
if (load_attempted)
return -ENOMEDIUM;
ide_do_start_stop(drive, disk, IDETAPE_LU_LOAD_MASK);
load_attempted = 1;
/* not about to be ready */
} else if (!(tape->sense_key == 2 && tape->asc == 4 &&
(tape->ascq == 1 || tape->ascq == 8)))
return -EIO;
msleep(100);
}
return -EIO;
}
static int idetape_flush_tape_buffers(ide_drive_t *drive)
{
struct ide_tape_obj *tape = drive->driver_data;
struct ide_atapi_pc pc;
int rc;
idetape_create_write_filemark_cmd(drive, &pc, 0);
rc = ide_queue_pc_tail(drive, tape->disk, &pc, NULL, 0);
if (rc)
return rc;
idetape_wait_ready(drive, 60 * 5 * HZ);
return 0;
}
static int ide_tape_read_position(ide_drive_t *drive)
{
idetape_tape_t *tape = drive->driver_data;
struct ide_atapi_pc pc;
u8 buf[20];
ide_debug_log(IDE_DBG_FUNC, "enter");
/* prep cmd */
ide_init_pc(&pc);
pc.c[0] = READ_POSITION;
pc.req_xfer = 20;
if (ide_queue_pc_tail(drive, tape->disk, &pc, buf, pc.req_xfer))
return -1;
if (!pc.error) {
ide_debug_log(IDE_DBG_FUNC, "BOP - %s",
(buf[0] & 0x80) ? "Yes" : "No");
ide_debug_log(IDE_DBG_FUNC, "EOP - %s",
(buf[0] & 0x40) ? "Yes" : "No");
if (buf[0] & 0x4) {
printk(KERN_INFO "ide-tape: Block location is unknown"
"to the tape\n");
clear_bit(ilog2(IDE_AFLAG_ADDRESS_VALID),
&drive->atapi_flags);
return -1;
} else {
ide_debug_log(IDE_DBG_FUNC, "Block Location: %u",
be32_to_cpup((__be32 *)&buf[4]));
tape->partition = buf[1];
tape->first_frame = be32_to_cpup((__be32 *)&buf[4]);
set_bit(ilog2(IDE_AFLAG_ADDRESS_VALID),
&drive->atapi_flags);
}
}
return tape->first_frame;
}
static void idetape_create_locate_cmd(ide_drive_t *drive,
struct ide_atapi_pc *pc,
unsigned int block, u8 partition, int skip)
{
ide_init_pc(pc);
pc->c[0] = POSITION_TO_ELEMENT;
pc->c[1] = 2;
put_unaligned(cpu_to_be32(block), (unsigned int *) &pc->c[3]);
pc->c[8] = partition;
pc->flags |= PC_FLAG_WAIT_FOR_DSC;
}
static void __ide_tape_discard_merge_buffer(ide_drive_t *drive)
{
idetape_tape_t *tape = drive->driver_data;
if (tape->chrdev_dir != IDETAPE_DIR_READ)
return;
clear_bit(ilog2(IDE_AFLAG_FILEMARK), &drive->atapi_flags);
tape->valid = 0;
if (tape->buf != NULL) {
kfree(tape->buf);
tape->buf = NULL;
}
tape->chrdev_dir = IDETAPE_DIR_NONE;
}
/*
* Position the tape to the requested block using the LOCATE packet command.
* A READ POSITION command is then issued to check where we are positioned. Like
* all higher level operations, we queue the commands at the tail of the request
* queue and wait for their completion.
*/
static int idetape_position_tape(ide_drive_t *drive, unsigned int block,
u8 partition, int skip)
{
idetape_tape_t *tape = drive->driver_data;
struct gendisk *disk = tape->disk;
int ret;
struct ide_atapi_pc pc;
if (tape->chrdev_dir == IDETAPE_DIR_READ)
__ide_tape_discard_merge_buffer(drive);
idetape_wait_ready(drive, 60 * 5 * HZ);
idetape_create_locate_cmd(drive, &pc, block, partition, skip);
ret = ide_queue_pc_tail(drive, disk, &pc, NULL, 0);
if (ret)
return ret;
ret = ide_tape_read_position(drive);
if (ret < 0)
return ret;
return 0;
}
static void ide_tape_discard_merge_buffer(ide_drive_t *drive,
int restore_position)
{
idetape_tape_t *tape = drive->driver_data;
int seek, position;
__ide_tape_discard_merge_buffer(drive);
if (restore_position) {
position = ide_tape_read_position(drive);
seek = position > 0 ? position : 0;
if (idetape_position_tape(drive, seek, 0, 0)) {
printk(KERN_INFO "ide-tape: %s: position_tape failed in"
" %s\n", tape->name, __func__);
return;
}
}
}
/*
* Generate a read/write request for the block device interface and wait for it
* to be serviced.
*/
static int idetape_queue_rw_tail(ide_drive_t *drive, int cmd, int size)
{
idetape_tape_t *tape = drive->driver_data;
struct request *rq;
int ret;
ide_debug_log(IDE_DBG_FUNC, "cmd: 0x%x, size: %d", cmd, size);
BUG_ON(cmd != REQ_IDETAPE_READ && cmd != REQ_IDETAPE_WRITE);
BUG_ON(size < 0 || size % tape->blk_size);
rq = blk_get_request(drive->queue, REQ_OP_DRV_IN, 0);
ide_req(rq)->type = ATA_PRIV_MISC;
scsi_req(rq)->cmd[13] = cmd;
rq->rq_disk = tape->disk;
rq->__sector = tape->first_frame;
if (size) {
ret = blk_rq_map_kern(drive->queue, rq, tape->buf, size,
GFP_NOIO);
if (ret)
goto out_put;
}
blk_execute_rq(drive->queue, tape->disk, rq, 0);
/* calculate the number of transferred bytes and update buffer state */
size -= scsi_req(rq)->resid_len;
tape->cur = tape->buf;
if (cmd == REQ_IDETAPE_READ)
tape->valid = size;
else
tape->valid = 0;
ret = size;
if (scsi_req(rq)->result == IDE_DRV_ERROR_GENERAL)
ret = -EIO;
out_put:
blk_put_request(rq);
return ret;
}
static void idetape_create_inquiry_cmd(struct ide_atapi_pc *pc)
{
ide_init_pc(pc);
pc->c[0] = INQUIRY;
pc->c[4] = 254;
pc->req_xfer = 254;
}
static void idetape_create_rewind_cmd(ide_drive_t *drive,
struct ide_atapi_pc *pc)
{
ide_init_pc(pc);
pc->c[0] = REZERO_UNIT;
pc->flags |= PC_FLAG_WAIT_FOR_DSC;
}
static void idetape_create_erase_cmd(struct ide_atapi_pc *pc)
{
ide_init_pc(pc);
pc->c[0] = ERASE;
pc->c[1] = 1;
pc->flags |= PC_FLAG_WAIT_FOR_DSC;
}
static void idetape_create_space_cmd(struct ide_atapi_pc *pc, int count, u8 cmd)
{
ide_init_pc(pc);
pc->c[0] = SPACE;
put_unaligned(cpu_to_be32(count), (unsigned int *) &pc->c[1]);
pc->c[1] = cmd;
pc->flags |= PC_FLAG_WAIT_FOR_DSC;
}
static void ide_tape_flush_merge_buffer(ide_drive_t *drive)
{
idetape_tape_t *tape = drive->driver_data;
if (tape->chrdev_dir != IDETAPE_DIR_WRITE) {
printk(KERN_ERR "ide-tape: bug: Trying to empty merge buffer"
" but we are not writing.\n");
return;
}
if (tape->buf) {
size_t aligned = roundup(tape->valid, tape->blk_size);
memset(tape->cur, 0, aligned - tape->valid);
idetape_queue_rw_tail(drive, REQ_IDETAPE_WRITE, aligned);
kfree(tape->buf);
tape->buf = NULL;
}
tape->chrdev_dir = IDETAPE_DIR_NONE;
}
static int idetape_init_rw(ide_drive_t *drive, int dir)
{
idetape_tape_t *tape = drive->driver_data;
int rc;
BUG_ON(dir != IDETAPE_DIR_READ && dir != IDETAPE_DIR_WRITE);
if (tape->chrdev_dir == dir)
return 0;
if (tape->chrdev_dir == IDETAPE_DIR_READ)
ide_tape_discard_merge_buffer(drive, 1);
else if (tape->chrdev_dir == IDETAPE_DIR_WRITE) {
ide_tape_flush_merge_buffer(drive);
idetape_flush_tape_buffers(drive);
}
if (tape->buf || tape->valid) {
printk(KERN_ERR "ide-tape: valid should be 0 now\n");
tape->valid = 0;
}
tape->buf = kmalloc(tape->buffer_size, GFP_KERNEL);
if (!tape->buf)
return -ENOMEM;
tape->chrdev_dir = dir;
tape->cur = tape->buf;
/*
* Issue a 0 rw command to ensure that DSC handshake is
* switched from completion mode to buffer available mode. No
* point in issuing this if DSC overlap isn't supported, some
* drives (Seagate STT3401A) will return an error.
*/
if (drive->dev_flags & IDE_DFLAG_DSC_OVERLAP) {
int cmd = dir == IDETAPE_DIR_READ ? REQ_IDETAPE_READ
: REQ_IDETAPE_WRITE;
rc = idetape_queue_rw_tail(drive, cmd, 0);
if (rc < 0) {
kfree(tape->buf);
tape->buf = NULL;
tape->chrdev_dir = IDETAPE_DIR_NONE;
return rc;
}
}
return 0;
}
static void idetape_pad_zeros(ide_drive_t *drive, int bcount)
{
idetape_tape_t *tape = drive->driver_data;
memset(tape->buf, 0, tape->buffer_size);
while (bcount) {
unsigned int count = min(tape->buffer_size, bcount);
idetape_queue_rw_tail(drive, REQ_IDETAPE_WRITE, count);
bcount -= count;
}
}
/*
* Rewinds the tape to the Beginning Of the current Partition (BOP). We
* currently support only one partition.
*/
static int idetape_rewind_tape(ide_drive_t *drive)
{
struct ide_tape_obj *tape = drive->driver_data;
struct gendisk *disk = tape->disk;
struct ide_atapi_pc pc;
int ret;
ide_debug_log(IDE_DBG_FUNC, "enter");
idetape_create_rewind_cmd(drive, &pc);
ret = ide_queue_pc_tail(drive, disk, &pc, NULL, 0);
if (ret)
return ret;
ret = ide_tape_read_position(drive);
if (ret < 0)
return ret;
return 0;
}
/* mtio.h compatible commands should be issued to the chrdev interface. */
static int idetape_blkdev_ioctl(ide_drive_t *drive, unsigned int cmd,
unsigned long arg)
{
idetape_tape_t *tape = drive->driver_data;
void __user *argp = (void __user *)arg;
struct idetape_config {
int dsc_rw_frequency;
int dsc_media_access_frequency;
int nr_stages;
} config;
ide_debug_log(IDE_DBG_FUNC, "cmd: 0x%04x", cmd);
switch (cmd) {
case 0x0340:
if (copy_from_user(&config, argp, sizeof(config)))
return -EFAULT;
tape->best_dsc_rw_freq = config.dsc_rw_frequency;
break;
case 0x0350:
memset(&config, 0, sizeof(config));
config.dsc_rw_frequency = (int) tape->best_dsc_rw_freq;
config.nr_stages = 1;
if (copy_to_user(argp, &config, sizeof(config)))
return -EFAULT;
break;
default:
return -EIO;
}
return 0;
}
static int idetape_space_over_filemarks(ide_drive_t *drive, short mt_op,
int mt_count)
{
idetape_tape_t *tape = drive->driver_data;
struct gendisk *disk = tape->disk;
struct ide_atapi_pc pc;
int retval, count = 0;
int sprev = !!(tape->caps[4] & 0x20);
ide_debug_log(IDE_DBG_FUNC, "mt_op: %d, mt_count: %d", mt_op, mt_count);
if (mt_count == 0)
return 0;
if (MTBSF == mt_op || MTBSFM == mt_op) {
if (!sprev)
return -EIO;
mt_count = -mt_count;
}
if (tape->chrdev_dir == IDETAPE_DIR_READ) {
tape->valid = 0;
if (test_and_clear_bit(ilog2(IDE_AFLAG_FILEMARK),
&drive->atapi_flags))
++count;
ide_tape_discard_merge_buffer(drive, 0);
}
switch (mt_op) {
case MTFSF:
case MTBSF:
idetape_create_space_cmd(&pc, mt_count - count,
IDETAPE_SPACE_OVER_FILEMARK);
return ide_queue_pc_tail(drive, disk, &pc, NULL, 0);
case MTFSFM:
case MTBSFM:
if (!sprev)
return -EIO;
retval = idetape_space_over_filemarks(drive, MTFSF,
mt_count - count);
if (retval)
return retval;
count = (MTBSFM == mt_op ? 1 : -1);
return idetape_space_over_filemarks(drive, MTFSF, count);
default:
printk(KERN_ERR "ide-tape: MTIO operation %d not supported\n",
mt_op);
return -EIO;
}
}
/*
* Our character device read / write functions.
*
* The tape is optimized to maximize throughput when it is transferring an
* integral number of the "continuous transfer limit", which is a parameter of
* the specific tape (26kB on my particular tape, 32kB for Onstream).
*
* As of version 1.3 of the driver, the character device provides an abstract
* continuous view of the media - any mix of block sizes (even 1 byte) on the
* same backup/restore procedure is supported. The driver will internally
* convert the requests to the recommended transfer unit, so that an unmatch
* between the user's block size to the recommended size will only result in a
* (slightly) increased driver overhead, but will no longer hit performance.
* This is not applicable to Onstream.
*/
static ssize_t idetape_chrdev_read(struct file *file, char __user *buf,
size_t count, loff_t *ppos)
{
struct ide_tape_obj *tape = file->private_data;
ide_drive_t *drive = tape->drive;
size_t done = 0;
ssize_t ret = 0;
int rc;
ide_debug_log(IDE_DBG_FUNC, "count %zd", count);
if (tape->chrdev_dir != IDETAPE_DIR_READ) {
if (test_bit(ilog2(IDE_AFLAG_DETECT_BS), &drive->atapi_flags))
if (count > tape->blk_size &&
(count % tape->blk_size) == 0)
tape->user_bs_factor = count / tape->blk_size;
}
rc = idetape_init_rw(drive, IDETAPE_DIR_READ);
if (rc < 0)
return rc;
while (done < count) {
size_t todo;
/* refill if staging buffer is empty */
if (!tape->valid) {
/* If we are at a filemark, nothing more to read */
if (test_bit(ilog2(IDE_AFLAG_FILEMARK),
&drive->atapi_flags))
break;
/* read */
if (idetape_queue_rw_tail(drive, REQ_IDETAPE_READ,
tape->buffer_size) <= 0)
break;
}
/* copy out */
todo = min_t(size_t, count - done, tape->valid);
if (copy_to_user(buf + done, tape->cur, todo))
ret = -EFAULT;
tape->cur += todo;
tape->valid -= todo;
done += todo;
}
if (!done && test_bit(ilog2(IDE_AFLAG_FILEMARK), &drive->atapi_flags)) {
idetape_space_over_filemarks(drive, MTFSF, 1);
return 0;
}
return ret ? ret : done;
}
static ssize_t idetape_chrdev_write(struct file *file, const char __user *buf,
size_t count, loff_t *ppos)
{
struct ide_tape_obj *tape = file->private_data;
ide_drive_t *drive = tape->drive;
size_t done = 0;
ssize_t ret = 0;
int rc;
/* The drive is write protected. */
if (tape->write_prot)
return -EACCES;
ide_debug_log(IDE_DBG_FUNC, "count %zd", count);
/* Initialize write operation */
rc = idetape_init_rw(drive, IDETAPE_DIR_WRITE);
if (rc < 0)
return rc;
while (done < count) {
size_t todo;
/* flush if staging buffer is full */
if (tape->valid == tape->buffer_size &&
idetape_queue_rw_tail(drive, REQ_IDETAPE_WRITE,
tape->buffer_size) <= 0)
return rc;
/* copy in */
todo = min_t(size_t, count - done,
tape->buffer_size - tape->valid);
if (copy_from_user(tape->cur, buf + done, todo))
ret = -EFAULT;
tape->cur += todo;
tape->valid += todo;
done += todo;
}
return ret ? ret : done;
}
static int idetape_write_filemark(ide_drive_t *drive)
{
struct ide_tape_obj *tape = drive->driver_data;
struct ide_atapi_pc pc;
/* Write a filemark */
idetape_create_write_filemark_cmd(drive, &pc, 1);
if (ide_queue_pc_tail(drive, tape->disk, &pc, NULL, 0)) {
printk(KERN_ERR "ide-tape: Couldn't write a filemark\n");
return -EIO;
}
return 0;
}
/*
* Called from idetape_chrdev_ioctl when the general mtio MTIOCTOP ioctl is
* requested.
*
* Note: MTBSF and MTBSFM are not supported when the tape doesn't support
* spacing over filemarks in the reverse direction. In this case, MTFSFM is also
* usually not supported.
*
* The following commands are currently not supported:
*
* MTFSS, MTBSS, MTWSM, MTSETDENSITY, MTSETDRVBUFFER, MT_ST_BOOLEANS,
* MT_ST_WRITE_THRESHOLD.
*/
static int idetape_mtioctop(ide_drive_t *drive, short mt_op, int mt_count)
{
idetape_tape_t *tape = drive->driver_data;
struct gendisk *disk = tape->disk;
struct ide_atapi_pc pc;
int i, retval;
ide_debug_log(IDE_DBG_FUNC, "MTIOCTOP ioctl: mt_op: %d, mt_count: %d",
mt_op, mt_count);
switch (mt_op) {
case MTFSF:
case MTFSFM:
case MTBSF:
case MTBSFM:
if (!mt_count)
return 0;
return idetape_space_over_filemarks(drive, mt_op, mt_count);
default:
break;
}
switch (mt_op) {
case MTWEOF:
if (tape->write_prot)
return -EACCES;
ide_tape_discard_merge_buffer(drive, 1);
for (i = 0; i < mt_count; i++) {
retval = idetape_write_filemark(drive);
if (retval)
return retval;
}
return 0;
case MTREW:
ide_tape_discard_merge_buffer(drive, 0);
if (idetape_rewind_tape(drive))
return -EIO;
return 0;
case MTLOAD:
ide_tape_discard_merge_buffer(drive, 0);
return ide_do_start_stop(drive, disk, IDETAPE_LU_LOAD_MASK);
case MTUNLOAD:
case MTOFFL:
/*
* If door is locked, attempt to unlock before
* attempting to eject.
*/
if (tape->door_locked) {
if (!ide_set_media_lock(drive, disk, 0))
tape->door_locked = DOOR_UNLOCKED;
}
ide_tape_discard_merge_buffer(drive, 0);
retval = ide_do_start_stop(drive, disk, !IDETAPE_LU_LOAD_MASK);
if (!retval)
clear_bit(ilog2(IDE_AFLAG_MEDIUM_PRESENT),
&drive->atapi_flags);
return retval;
case MTNOP:
ide_tape_discard_merge_buffer(drive, 0);
return idetape_flush_tape_buffers(drive);
case MTRETEN:
ide_tape_discard_merge_buffer(drive, 0);
return ide_do_start_stop(drive, disk,
IDETAPE_LU_RETENSION_MASK | IDETAPE_LU_LOAD_MASK);
case MTEOM:
idetape_create_space_cmd(&pc, 0, IDETAPE_SPACE_TO_EOD);
return ide_queue_pc_tail(drive, disk, &pc, NULL, 0);
case MTERASE:
(void)idetape_rewind_tape(drive);
idetape_create_erase_cmd(&pc);
return ide_queue_pc_tail(drive, disk, &pc, NULL, 0);
case MTSETBLK:
if (mt_count) {
if (mt_count < tape->blk_size ||
mt_count % tape->blk_size)
return -EIO;
tape->user_bs_factor = mt_count / tape->blk_size;
clear_bit(ilog2(IDE_AFLAG_DETECT_BS),
&drive->atapi_flags);
} else
set_bit(ilog2(IDE_AFLAG_DETECT_BS),
&drive->atapi_flags);
return 0;
case MTSEEK:
ide_tape_discard_merge_buffer(drive, 0);
return idetape_position_tape(drive,
mt_count * tape->user_bs_factor, tape->partition, 0);
case MTSETPART:
ide_tape_discard_merge_buffer(drive, 0);
return idetape_position_tape(drive, 0, mt_count, 0);
case MTFSR:
case MTBSR:
case MTLOCK:
retval = ide_set_media_lock(drive, disk, 1);
if (retval)
return retval;
tape->door_locked = DOOR_EXPLICITLY_LOCKED;
return 0;
case MTUNLOCK:
retval = ide_set_media_lock(drive, disk, 0);
if (retval)
return retval;
tape->door_locked = DOOR_UNLOCKED;
return 0;
default:
printk(KERN_ERR "ide-tape: MTIO operation %d not supported\n",
mt_op);
return -EIO;
}
}
/*
* Our character device ioctls. General mtio.h magnetic io commands are
* supported here, and not in the corresponding block interface. Our own
* ide-tape ioctls are supported on both interfaces.
*/
static long do_idetape_chrdev_ioctl(struct file *file,
unsigned int cmd, unsigned long arg)
{
struct ide_tape_obj *tape = file->private_data;
ide_drive_t *drive = tape->drive;
struct mtop mtop;
struct mtget mtget;
struct mtpos mtpos;
int block_offset = 0, position = tape->first_frame;
void __user *argp = (void __user *)arg;
ide_debug_log(IDE_DBG_FUNC, "cmd: 0x%x", cmd);
if (tape->chrdev_dir == IDETAPE_DIR_WRITE) {
ide_tape_flush_merge_buffer(drive);
idetape_flush_tape_buffers(drive);
}
if (cmd == MTIOCGET || cmd == MTIOCPOS) {
block_offset = tape->valid /
(tape->blk_size * tape->user_bs_factor);
position = ide_tape_read_position(drive);
if (position < 0)
return -EIO;
}
switch (cmd) {
case MTIOCTOP:
if (copy_from_user(&mtop, argp, sizeof(struct mtop)))
return -EFAULT;
return idetape_mtioctop(drive, mtop.mt_op, mtop.mt_count);
case MTIOCGET:
memset(&mtget, 0, sizeof(struct mtget));
mtget.mt_type = MT_ISSCSI2;
mtget.mt_blkno = position / tape->user_bs_factor - block_offset;
mtget.mt_dsreg =
((tape->blk_size * tape->user_bs_factor)
<< MT_ST_BLKSIZE_SHIFT) & MT_ST_BLKSIZE_MASK;
if (tape->drv_write_prot)
mtget.mt_gstat |= GMT_WR_PROT(0xffffffff);
if (copy_to_user(argp, &mtget, sizeof(struct mtget)))
return -EFAULT;
return 0;
case MTIOCPOS:
mtpos.mt_blkno = position / tape->user_bs_factor - block_offset;
if (copy_to_user(argp, &mtpos, sizeof(struct mtpos)))
return -EFAULT;
return 0;
default:
if (tape->chrdev_dir == IDETAPE_DIR_READ)
ide_tape_discard_merge_buffer(drive, 1);
return idetape_blkdev_ioctl(drive, cmd, arg);
}
}
static long idetape_chrdev_ioctl(struct file *file,
unsigned int cmd, unsigned long arg)
{
long ret;
mutex_lock(&ide_tape_mutex);
ret = do_idetape_chrdev_ioctl(file, cmd, arg);
mutex_unlock(&ide_tape_mutex);
return ret;
}
/*
* Do a mode sense page 0 with block descriptor and if it succeeds set the tape
* block size with the reported value.
*/
static void ide_tape_get_bsize_from_bdesc(ide_drive_t *drive)
{
idetape_tape_t *tape = drive->driver_data;
struct ide_atapi_pc pc;
u8 buf[12];
idetape_create_mode_sense_cmd(&pc, IDETAPE_BLOCK_DESCRIPTOR);
if (ide_queue_pc_tail(drive, tape->disk, &pc, buf, pc.req_xfer)) {
printk(KERN_ERR "ide-tape: Can't get block descriptor\n");
if (tape->blk_size == 0) {
printk(KERN_WARNING "ide-tape: Cannot deal with zero "
"block size, assuming 32k\n");
tape->blk_size = 32768;
}
return;
}
tape->blk_size = (buf[4 + 5] << 16) +
(buf[4 + 6] << 8) +
buf[4 + 7];
tape->drv_write_prot = (buf[2] & 0x80) >> 7;
ide_debug_log(IDE_DBG_FUNC, "blk_size: %d, write_prot: %d",
tape->blk_size, tape->drv_write_prot);
}
static int idetape_chrdev_open(struct inode *inode, struct file *filp)
{
unsigned int minor = iminor(inode), i = minor & ~0xc0;
ide_drive_t *drive;
idetape_tape_t *tape;
int retval;
if (i >= MAX_HWIFS * MAX_DRIVES)
return -ENXIO;
mutex_lock(&idetape_chrdev_mutex);
tape = ide_tape_get(NULL, true, i);
if (!tape) {
mutex_unlock(&idetape_chrdev_mutex);
return -ENXIO;
}
drive = tape->drive;
filp->private_data = tape;
ide_debug_log(IDE_DBG_FUNC, "enter");
/*
* 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 (test_and_set_bit(ilog2(IDE_AFLAG_BUSY), &drive->atapi_flags)) {
retval = -EBUSY;
goto out_put_tape;
}
retval = idetape_wait_ready(drive, 60 * HZ);
if (retval) {
clear_bit(ilog2(IDE_AFLAG_BUSY), &drive->atapi_flags);
printk(KERN_ERR "ide-tape: %s: drive not ready\n", tape->name);
goto out_put_tape;
}
ide_tape_read_position(drive);
if (!test_bit(ilog2(IDE_AFLAG_ADDRESS_VALID), &drive->atapi_flags))
(void)idetape_rewind_tape(drive);
/* Read block size and write protect status from drive. */
ide_tape_get_bsize_from_bdesc(drive);
/* Set write protect flag if device is opened as read-only. */
if ((filp->f_flags & O_ACCMODE) == O_RDONLY)
tape->write_prot = 1;
else
tape->write_prot = tape->drv_write_prot;
/* Make sure drive isn't write protected if user wants to write. */
if (tape->write_prot) {
if ((filp->f_flags & O_ACCMODE) == O_WRONLY ||
(filp->f_flags & O_ACCMODE) == O_RDWR) {
clear_bit(ilog2(IDE_AFLAG_BUSY), &drive->atapi_flags);
retval = -EROFS;
goto out_put_tape;
}
}
/* Lock the tape drive door so user can't eject. */
if (tape->chrdev_dir == IDETAPE_DIR_NONE) {
if (!ide_set_media_lock(drive, tape->disk, 1)) {
if (tape->door_locked != DOOR_EXPLICITLY_LOCKED)
tape->door_locked = DOOR_LOCKED;
}
}
mutex_unlock(&idetape_chrdev_mutex);
return 0;
out_put_tape:
ide_tape_put(tape);
mutex_unlock(&idetape_chrdev_mutex);
return retval;
}
static void idetape_write_release(ide_drive_t *drive, unsigned int minor)
{
idetape_tape_t *tape = drive->driver_data;
ide_tape_flush_merge_buffer(drive);
tape->buf = kmalloc(tape->buffer_size, GFP_KERNEL);
if (tape->buf != NULL) {
idetape_pad_zeros(drive, tape->blk_size *
(tape->user_bs_factor - 1));
kfree(tape->buf);
tape->buf = NULL;
}
idetape_write_filemark(drive);
idetape_flush_tape_buffers(drive);
idetape_flush_tape_buffers(drive);
}
static int idetape_chrdev_release(struct inode *inode, struct file *filp)
{
struct ide_tape_obj *tape = filp->private_data;
ide_drive_t *drive = tape->drive;
unsigned int minor = iminor(inode);
mutex_lock(&idetape_chrdev_mutex);
tape = drive->driver_data;
ide_debug_log(IDE_DBG_FUNC, "enter");
if (tape->chrdev_dir == IDETAPE_DIR_WRITE)
idetape_write_release(drive, minor);
if (tape->chrdev_dir == IDETAPE_DIR_READ) {
if (minor < 128)
ide_tape_discard_merge_buffer(drive, 1);
}
if (minor < 128 && test_bit(ilog2(IDE_AFLAG_MEDIUM_PRESENT),
&drive->atapi_flags))
(void) idetape_rewind_tape(drive);
if (tape->chrdev_dir == IDETAPE_DIR_NONE) {
if (tape->door_locked == DOOR_LOCKED) {
if (!ide_set_media_lock(drive, tape->disk, 0))
tape->door_locked = DOOR_UNLOCKED;
}
}
clear_bit(ilog2(IDE_AFLAG_BUSY), &drive->atapi_flags);
ide_tape_put(tape);
mutex_unlock(&idetape_chrdev_mutex);
return 0;
}
static void idetape_get_inquiry_results(ide_drive_t *drive)
{
idetape_tape_t *tape = drive->driver_data;
struct ide_atapi_pc pc;
u8 pc_buf[256];
char fw_rev[4], vendor_id[8], product_id[16];
idetape_create_inquiry_cmd(&pc);
if (ide_queue_pc_tail(drive, tape->disk, &pc, pc_buf, pc.req_xfer)) {
printk(KERN_ERR "ide-tape: %s: can't get INQUIRY results\n",
tape->name);
return;
}
memcpy(vendor_id, &pc_buf[8], 8);
memcpy(product_id, &pc_buf[16], 16);
memcpy(fw_rev, &pc_buf[32], 4);
ide_fixstring(vendor_id, 8, 0);
ide_fixstring(product_id, 16, 0);
ide_fixstring(fw_rev, 4, 0);
printk(KERN_INFO "ide-tape: %s <-> %s: %.8s %.16s rev %.4s\n",
drive->name, tape->name, vendor_id, product_id, fw_rev);
}
/*
* Ask the tape about its various parameters. In particular, we will adjust our
* data transfer buffer size to the recommended value as returned by the tape.
*/
static void idetape_get_mode_sense_results(ide_drive_t *drive)
{
idetape_tape_t *tape = drive->driver_data;
struct ide_atapi_pc pc;
u8 buf[24], *caps;
u8 speed, max_speed;
idetape_create_mode_sense_cmd(&pc, IDETAPE_CAPABILITIES_PAGE);
if (ide_queue_pc_tail(drive, tape->disk, &pc, buf, pc.req_xfer)) {
printk(KERN_ERR "ide-tape: Can't get tape parameters - assuming"
" some default values\n");
tape->blk_size = 512;
put_unaligned(52, (u16 *)&tape->caps[12]);
put_unaligned(540, (u16 *)&tape->caps[14]);
put_unaligned(6*52, (u16 *)&tape->caps[16]);
return;
}
caps = buf + 4 + buf[3];
/* convert to host order and save for later use */
speed = be16_to_cpup((__be16 *)&caps[14]);
max_speed = be16_to_cpup((__be16 *)&caps[8]);
*(u16 *)&caps[8] = max_speed;
*(u16 *)&caps[12] = be16_to_cpup((__be16 *)&caps[12]);
*(u16 *)&caps[14] = speed;
*(u16 *)&caps[16] = be16_to_cpup((__be16 *)&caps[16]);
if (!speed) {
printk(KERN_INFO "ide-tape: %s: invalid tape speed "
"(assuming 650KB/sec)\n", drive->name);
*(u16 *)&caps[14] = 650;
}
if (!max_speed) {
printk(KERN_INFO "ide-tape: %s: invalid max_speed "
"(assuming 650KB/sec)\n", drive->name);
*(u16 *)&caps[8] = 650;
}
memcpy(&tape->caps, caps, 20);
/* device lacks locking support according to capabilities page */
if ((caps[6] & 1) == 0)
drive->dev_flags &= ~IDE_DFLAG_DOORLOCKING;
if (caps[7] & 0x02)
tape->blk_size = 512;
else if (caps[7] & 0x04)
tape->blk_size = 1024;
}
#ifdef CONFIG_IDE_PROC_FS
#define ide_tape_devset_get(name, field) \
static int get_##name(ide_drive_t *drive) \
{ \
idetape_tape_t *tape = drive->driver_data; \
return tape->field; \
}
#define ide_tape_devset_set(name, field) \
static int set_##name(ide_drive_t *drive, int arg) \
{ \
idetape_tape_t *tape = drive->driver_data; \
tape->field = arg; \
return 0; \
}
#define ide_tape_devset_rw_field(_name, _field) \
ide_tape_devset_get(_name, _field) \
ide_tape_devset_set(_name, _field) \
IDE_DEVSET(_name, DS_SYNC, get_##_name, set_##_name)
#define ide_tape_devset_r_field(_name, _field) \
ide_tape_devset_get(_name, _field) \
IDE_DEVSET(_name, 0, get_##_name, NULL)
static int mulf_tdsc(ide_drive_t *drive) { return 1000; }
static int divf_tdsc(ide_drive_t *drive) { return HZ; }
static int divf_buffer(ide_drive_t *drive) { return 2; }
static int divf_buffer_size(ide_drive_t *drive) { return 1024; }
ide_devset_rw_flag(dsc_overlap, IDE_DFLAG_DSC_OVERLAP);
ide_tape_devset_rw_field(tdsc, best_dsc_rw_freq);
ide_tape_devset_r_field(avg_speed, avg_speed);
ide_tape_devset_r_field(speed, caps[14]);
ide_tape_devset_r_field(buffer, caps[16]);
ide_tape_devset_r_field(buffer_size, buffer_size);
static const struct ide_proc_devset idetape_settings[] = {
__IDE_PROC_DEVSET(avg_speed, 0, 0xffff, NULL, NULL),
__IDE_PROC_DEVSET(buffer, 0, 0xffff, NULL, divf_buffer),
__IDE_PROC_DEVSET(buffer_size, 0, 0xffff, NULL, divf_buffer_size),
__IDE_PROC_DEVSET(dsc_overlap, 0, 1, NULL, NULL),
__IDE_PROC_DEVSET(speed, 0, 0xffff, NULL, NULL),
__IDE_PROC_DEVSET(tdsc, IDETAPE_DSC_RW_MIN, IDETAPE_DSC_RW_MAX,
mulf_tdsc, divf_tdsc),
{ NULL },
};
#endif
/*
* The function below is called to:
*
* 1. Initialize our various state variables.
* 2. Ask the tape for its capabilities.
* 3. Allocate a buffer which will be used for data transfer. The buffer size
* is chosen based on the recommendation which we received in step 2.
*
* Note that at this point ide.c already assigned us an irq, so that we can
* queue requests here and wait for their completion.
*/
static void idetape_setup(ide_drive_t *drive, idetape_tape_t *tape, int minor)
{
unsigned long t;
int speed;
u16 *ctl = (u16 *)&tape->caps[12];
ide_debug_log(IDE_DBG_FUNC, "minor: %d", minor);
drive->pc_callback = ide_tape_callback;
drive->dev_flags |= IDE_DFLAG_DSC_OVERLAP;
if (drive->hwif->host_flags & IDE_HFLAG_NO_DSC) {
printk(KERN_INFO "ide-tape: %s: disabling DSC overlap\n",
tape->name);
drive->dev_flags &= ~IDE_DFLAG_DSC_OVERLAP;
}
/* Seagate Travan drives do not support DSC overlap. */
if (strstr((char *)&drive->id[ATA_ID_PROD], "Seagate STT3401"))
drive->dev_flags &= ~IDE_DFLAG_DSC_OVERLAP;
tape->minor = minor;
tape->name[0] = 'h';
tape->name[1] = 't';
tape->name[2] = '0' + minor;
tape->chrdev_dir = IDETAPE_DIR_NONE;
idetape_get_inquiry_results(drive);
idetape_get_mode_sense_results(drive);
ide_tape_get_bsize_from_bdesc(drive);
tape->user_bs_factor = 1;
tape->buffer_size = *ctl * tape->blk_size;
while (tape->buffer_size > 0xffff) {
printk(KERN_NOTICE "ide-tape: decreasing stage size\n");
*ctl /= 2;
tape->buffer_size = *ctl * tape->blk_size;
}
/* select the "best" DSC read/write polling freq */
speed = max(*(u16 *)&tape->caps[14], *(u16 *)&tape->caps[8]);
t = (IDETAPE_FIFO_THRESHOLD * tape->buffer_size * HZ) / (speed * 1000);
/*
* Ensure that the number we got makes sense; limit it within
* IDETAPE_DSC_RW_MIN and IDETAPE_DSC_RW_MAX.
*/
tape->best_dsc_rw_freq = clamp_t(unsigned long, t, IDETAPE_DSC_RW_MIN,
IDETAPE_DSC_RW_MAX);
printk(KERN_INFO "ide-tape: %s <-> %s: %dKBps, %d*%dkB buffer, "
"%ums tDSC%s\n",
drive->name, tape->name, *(u16 *)&tape->caps[14],
(*(u16 *)&tape->caps[16] * 512) / tape->buffer_size,
tape->buffer_size / 1024,
jiffies_to_msecs(tape->best_dsc_rw_freq),
(drive->dev_flags & IDE_DFLAG_USING_DMA) ? ", DMA" : "");
ide_proc_register_driver(drive, tape->driver);
}
static void ide_tape_remove(ide_drive_t *drive)
{
idetape_tape_t *tape = drive->driver_data;
ide_proc_unregister_driver(drive, tape->driver);
device_del(&tape->dev);
ide_unregister_region(tape->disk);
mutex_lock(&idetape_ref_mutex);
put_device(&tape->dev);
mutex_unlock(&idetape_ref_mutex);
}
static void ide_tape_release(struct device *dev)
{
struct ide_tape_obj *tape = to_ide_drv(dev, ide_tape_obj);
ide_drive_t *drive = tape->drive;
struct gendisk *g = tape->disk;
BUG_ON(tape->valid);
drive->dev_flags &= ~IDE_DFLAG_DSC_OVERLAP;
drive->driver_data = NULL;
device_destroy(idetape_sysfs_class, MKDEV(IDETAPE_MAJOR, tape->minor));
device_destroy(idetape_sysfs_class,
MKDEV(IDETAPE_MAJOR, tape->minor + 128));
idetape_devs[tape->minor] = NULL;
g->private_data = NULL;
put_disk(g);
kfree(tape);
}
#ifdef CONFIG_IDE_PROC_FS
static int idetape_name_proc_show(struct seq_file *m, void *v)
{
ide_drive_t *drive = (ide_drive_t *) m->private;
idetape_tape_t *tape = drive->driver_data;
seq_printf(m, "%s\n", tape->name);
return 0;
}
static ide_proc_entry_t idetape_proc[] = {
{ "capacity", S_IFREG|S_IRUGO, ide_capacity_proc_show },
{ "name", S_IFREG|S_IRUGO, idetape_name_proc_show },
{}
};
static ide_proc_entry_t *ide_tape_proc_entries(ide_drive_t *drive)
{
return idetape_proc;
}
static const struct ide_proc_devset *ide_tape_proc_devsets(ide_drive_t *drive)
{
return idetape_settings;
}
#endif
static int ide_tape_probe(ide_drive_t *);
static struct ide_driver idetape_driver = {
.gen_driver = {
.owner = THIS_MODULE,
.name = "ide-tape",
.bus = &ide_bus_type,
},
.probe = ide_tape_probe,
.remove = ide_tape_remove,
.version = IDETAPE_VERSION,
.do_request = idetape_do_request,
#ifdef CONFIG_IDE_PROC_FS
.proc_entries = ide_tape_proc_entries,
.proc_devsets = ide_tape_proc_devsets,
#endif
};
/* Our character device supporting functions, passed to register_chrdev. */
static const struct file_operations idetape_fops = {
.owner = THIS_MODULE,
.read = idetape_chrdev_read,
.write = idetape_chrdev_write,
.unlocked_ioctl = idetape_chrdev_ioctl,
.open = idetape_chrdev_open,
.release = idetape_chrdev_release,
.llseek = noop_llseek,
};
static int idetape_open(struct block_device *bdev, fmode_t mode)
{
struct ide_tape_obj *tape;
mutex_lock(&ide_tape_mutex);
tape = ide_tape_get(bdev->bd_disk, false, 0);
mutex_unlock(&ide_tape_mutex);
if (!tape)
return -ENXIO;
return 0;
}
static void idetape_release(struct gendisk *disk, fmode_t mode)
{
struct ide_tape_obj *tape = ide_drv_g(disk, ide_tape_obj);
mutex_lock(&ide_tape_mutex);
ide_tape_put(tape);
mutex_unlock(&ide_tape_mutex);
}
static int idetape_ioctl(struct block_device *bdev, fmode_t mode,
unsigned int cmd, unsigned long arg)
{
struct ide_tape_obj *tape = ide_drv_g(bdev->bd_disk, ide_tape_obj);
ide_drive_t *drive = tape->drive;
int err;
mutex_lock(&ide_tape_mutex);
err = generic_ide_ioctl(drive, bdev, cmd, arg);
if (err == -EINVAL)
err = idetape_blkdev_ioctl(drive, cmd, arg);
mutex_unlock(&ide_tape_mutex);
return err;
}
static const struct block_device_operations idetape_block_ops = {
.owner = THIS_MODULE,
.open = idetape_open,
.release = idetape_release,
.ioctl = idetape_ioctl,
};
static int ide_tape_probe(ide_drive_t *drive)
{
idetape_tape_t *tape;
struct gendisk *g;
int minor;
ide_debug_log(IDE_DBG_FUNC, "enter");
if (!strstr(DRV_NAME, drive->driver_req))
goto failed;
if (drive->media != ide_tape)
goto failed;
if ((drive->dev_flags & IDE_DFLAG_ID_READ) &&
ide_check_atapi_device(drive, DRV_NAME) == 0) {
printk(KERN_ERR "ide-tape: %s: not supported by this version of"
" the driver\n", drive->name);
goto failed;
}
tape = kzalloc(sizeof(idetape_tape_t), GFP_KERNEL);
if (tape == NULL) {
printk(KERN_ERR "ide-tape: %s: Can't allocate a tape struct\n",
drive->name);
goto failed;
}
g = alloc_disk(1 << PARTN_BITS);
if (!g)
goto out_free_tape;
ide_init_disk(g, drive);
tape->dev.parent = &drive->gendev;
tape->dev.release = ide_tape_release;
dev_set_name(&tape->dev, "%s", dev_name(&drive->gendev));
if (device_register(&tape->dev))
goto out_free_disk;
tape->drive = drive;
tape->driver = &idetape_driver;
tape->disk = g;
g->private_data = &tape->driver;
drive->driver_data = tape;
mutex_lock(&idetape_ref_mutex);
for (minor = 0; idetape_devs[minor]; minor++)
;
idetape_devs[minor] = tape;
mutex_unlock(&idetape_ref_mutex);
idetape_setup(drive, tape, minor);
device_create(idetape_sysfs_class, &drive->gendev,
MKDEV(IDETAPE_MAJOR, minor), NULL, "%s", tape->name);
device_create(idetape_sysfs_class, &drive->gendev,
MKDEV(IDETAPE_MAJOR, minor + 128), NULL,
"n%s", tape->name);
g->fops = &idetape_block_ops;
ide_register_region(g);
return 0;
out_free_disk:
put_disk(g);
out_free_tape:
kfree(tape);
failed:
return -ENODEV;
}
static void __exit idetape_exit(void)
{
driver_unregister(&idetape_driver.gen_driver);
class_destroy(idetape_sysfs_class);
unregister_chrdev(IDETAPE_MAJOR, "ht");
}
static int __init idetape_init(void)
{
int error = 1;
idetape_sysfs_class = class_create(THIS_MODULE, "ide_tape");
if (IS_ERR(idetape_sysfs_class)) {
idetape_sysfs_class = NULL;
printk(KERN_ERR "Unable to create sysfs class for ide tapes\n");
error = -EBUSY;
goto out;
}
if (register_chrdev(IDETAPE_MAJOR, "ht", &idetape_fops)) {
printk(KERN_ERR "ide-tape: Failed to register chrdev"
" interface\n");
error = -EBUSY;
goto out_free_class;
}
error = driver_register(&idetape_driver.gen_driver);
if (error)
goto out_free_chrdev;
return 0;
out_free_chrdev:
unregister_chrdev(IDETAPE_MAJOR, "ht");
out_free_class:
class_destroy(idetape_sysfs_class);
out:
return error;
}
MODULE_ALIAS("ide:*m-tape*");
module_init(idetape_init);
module_exit(idetape_exit);
MODULE_ALIAS_CHARDEV_MAJOR(IDETAPE_MAJOR);
MODULE_DESCRIPTION("ATAPI Streaming TAPE Driver");
MODULE_LICENSE("GPL");
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