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linux/drivers/block/paride/pt.c
Arjan van de Ven 2b8693c061 [PATCH] mark struct file_operations const 3 
Many struct file_operations in the kernel can be "const".  Marking them const
moves these to the .rodata section, which avoids false sharing with potential
dirty data.  In addition it'll catch accidental writes at compile time to
these shared resources.

Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-12 09:48:45 -08:00

1006 lines
23 KiB
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/*
pt.c (c) 1998 Grant R. Guenther <grant@torque.net>
Under the terms of the GNU General Public License.
This is the high-level driver for parallel port ATAPI tape
drives based on chips supported by the paride module.
The driver implements both rewinding and non-rewinding
devices, filemarks, and the rewind ioctl. It allocates
a small internal "bounce buffer" for each open device, but
otherwise expects buffering and blocking to be done at the
user level. As with most block-structured tapes, short
writes are padded to full tape blocks, so reading back a file
may return more data than was actually written.
By default, the driver will autoprobe for a single parallel
port ATAPI tape drive, but if their individual parameters are
specified, the driver can handle up to 4 drives.
The rewinding devices are named /dev/pt0, /dev/pt1, ...
while the non-rewinding devices are /dev/npt0, /dev/npt1, etc.
The behaviour of the pt driver can be altered by setting
some parameters from the insmod command line. The following
parameters are adjustable:
drive0 These four arguments can be arrays of
drive1 1-6 integers as follows:
drive2
drive3 <prt>,<pro>,<uni>,<mod>,<slv>,<dly>
Where,
<prt> is the base of the parallel port address for
the corresponding drive. (required)
<pro> is the protocol number for the adapter that
supports this drive. These numbers are
logged by 'paride' when the protocol modules
are initialised. (0 if not given)
<uni> for those adapters that support chained
devices, this is the unit selector for the
chain of devices on the given port. It should
be zero for devices that don't support chaining.
(0 if not given)
<mod> this can be -1 to choose the best mode, or one
of the mode numbers supported by the adapter.
(-1 if not given)
<slv> ATAPI devices can be jumpered to master or slave.
Set this to 0 to choose the master drive, 1 to
choose the slave, -1 (the default) to choose the
first drive found.
<dly> some parallel ports require the driver to
go more slowly. -1 sets a default value that
should work with the chosen protocol. Otherwise,
set this to a small integer, the larger it is
the slower the port i/o. In some cases, setting
this to zero will speed up the device. (default -1)
major You may use this parameter to overide the
default major number (96) that this driver
will use. Be sure to change the device
name as well.
name This parameter is a character string that
contains the name the kernel will use for this
device (in /proc output, for instance).
(default "pt").
verbose This parameter controls the amount of logging
that the driver will do. Set it to 0 for
normal operation, 1 to see autoprobe progress
messages, or 2 to see additional debugging
output. (default 0)
If this driver is built into the kernel, you can use
the following command line parameters, with the same values
as the corresponding module parameters listed above:
pt.drive0
pt.drive1
pt.drive2
pt.drive3
In addition, you can use the parameter pt.disable to disable
the driver entirely.
*/
/* Changes:
1.01 GRG 1998.05.06 Round up transfer size, fix ready_wait,
loosed interpretation of ATAPI standard
for clearing error status.
Eliminate sti();
1.02 GRG 1998.06.16 Eliminate an Ugh.
1.03 GRG 1998.08.15 Adjusted PT_TMO, use HZ in loop timing,
extra debugging
1.04 GRG 1998.09.24 Repair minor coding error, added jumbo support
*/
#define PT_VERSION "1.04"
#define PT_MAJOR 96
#define PT_NAME "pt"
#define PT_UNITS 4
/* Here are things one can override from the insmod command.
Most are autoprobed by paride unless set here. Verbose is on
by default.
*/
static int verbose = 0;
static int major = PT_MAJOR;
static char *name = PT_NAME;
static int disable = 0;
static int drive0[6] = { 0, 0, 0, -1, -1, -1 };
static int drive1[6] = { 0, 0, 0, -1, -1, -1 };
static int drive2[6] = { 0, 0, 0, -1, -1, -1 };
static int drive3[6] = { 0, 0, 0, -1, -1, -1 };
static int (*drives[4])[6] = {&drive0, &drive1, &drive2, &drive3};
#define D_PRT 0
#define D_PRO 1
#define D_UNI 2
#define D_MOD 3
#define D_SLV 4
#define D_DLY 5
#define DU (*drives[unit])
/* end of parameters */
#include <linux/module.h>
#include <linux/init.h>
#include <linux/fs.h>
#include <linux/delay.h>
#include <linux/slab.h>
#include <linux/mtio.h>
#include <linux/device.h>
#include <linux/sched.h> /* current, TASK_*, schedule_timeout() */
#include <asm/uaccess.h>
module_param(verbose, bool, 0);
module_param(major, int, 0);
module_param(name, charp, 0);
module_param_array(drive0, int, NULL, 0);
module_param_array(drive1, int, NULL, 0);
module_param_array(drive2, int, NULL, 0);
module_param_array(drive3, int, NULL, 0);
#include "paride.h"
#define PT_MAX_RETRIES 5
#define PT_TMO 3000 /* interrupt timeout in jiffies */
#define PT_SPIN_DEL 50 /* spin delay in micro-seconds */
#define PT_RESET_TMO 30 /* 30 seconds */
#define PT_READY_TMO 60 /* 60 seconds */
#define PT_REWIND_TMO 1200 /* 20 minutes */
#define PT_SPIN ((1000000/(HZ*PT_SPIN_DEL))*PT_TMO)
#define STAT_ERR 0x00001
#define STAT_INDEX 0x00002
#define STAT_ECC 0x00004
#define STAT_DRQ 0x00008
#define STAT_SEEK 0x00010
#define STAT_WRERR 0x00020
#define STAT_READY 0x00040
#define STAT_BUSY 0x00080
#define STAT_SENSE 0x1f000
#define ATAPI_TEST_READY 0x00
#define ATAPI_REWIND 0x01
#define ATAPI_REQ_SENSE 0x03
#define ATAPI_READ_6 0x08
#define ATAPI_WRITE_6 0x0a
#define ATAPI_WFM 0x10
#define ATAPI_IDENTIFY 0x12
#define ATAPI_MODE_SENSE 0x1a
#define ATAPI_LOG_SENSE 0x4d
static int pt_open(struct inode *inode, struct file *file);
static int pt_ioctl(struct inode *inode, struct file *file,
unsigned int cmd, unsigned long arg);
static int pt_release(struct inode *inode, struct file *file);
static ssize_t pt_read(struct file *filp, char __user *buf,
size_t count, loff_t * ppos);
static ssize_t pt_write(struct file *filp, const char __user *buf,
size_t count, loff_t * ppos);
static int pt_detect(void);
/* bits in tape->flags */
#define PT_MEDIA 1
#define PT_WRITE_OK 2
#define PT_REWIND 4
#define PT_WRITING 8
#define PT_READING 16
#define PT_EOF 32
#define PT_NAMELEN 8
#define PT_BUFSIZE 16384
struct pt_unit {
struct pi_adapter pia; /* interface to paride layer */
struct pi_adapter *pi;
int flags; /* various state flags */
int last_sense; /* result of last request sense */
int drive; /* drive */
atomic_t available; /* 1 if access is available 0 otherwise */
int bs; /* block size */
int capacity; /* Size of tape in KB */
int present; /* device present ? */
char *bufptr;
char name[PT_NAMELEN]; /* pf0, pf1, ... */
};
static int pt_identify(struct pt_unit *tape);
static struct pt_unit pt[PT_UNITS];
static char pt_scratch[512]; /* scratch block buffer */
/* kernel glue structures */
static const struct file_operations pt_fops = {
.owner = THIS_MODULE,
.read = pt_read,
.write = pt_write,
.ioctl = pt_ioctl,
.open = pt_open,
.release = pt_release,
};
/* sysfs class support */
static struct class *pt_class;
static inline int status_reg(struct pi_adapter *pi)
{
return pi_read_regr(pi, 1, 6);
}
static inline int read_reg(struct pi_adapter *pi, int reg)
{
return pi_read_regr(pi, 0, reg);
}
static inline void write_reg(struct pi_adapter *pi, int reg, int val)
{
pi_write_regr(pi, 0, reg, val);
}
static inline u8 DRIVE(struct pt_unit *tape)
{
return 0xa0+0x10*tape->drive;
}
static int pt_wait(struct pt_unit *tape, int go, int stop, char *fun, char *msg)
{
int j, r, e, s, p;
struct pi_adapter *pi = tape->pi;
j = 0;
while ((((r = status_reg(pi)) & go) || (stop && (!(r & stop))))
&& (j++ < PT_SPIN))
udelay(PT_SPIN_DEL);
if ((r & (STAT_ERR & stop)) || (j >= PT_SPIN)) {
s = read_reg(pi, 7);
e = read_reg(pi, 1);
p = read_reg(pi, 2);
if (j >= PT_SPIN)
e |= 0x100;
if (fun)
printk("%s: %s %s: alt=0x%x stat=0x%x err=0x%x"
" loop=%d phase=%d\n",
tape->name, fun, msg, r, s, e, j, p);
return (e << 8) + s;
}
return 0;
}
static int pt_command(struct pt_unit *tape, char *cmd, int dlen, char *fun)
{
struct pi_adapter *pi = tape->pi;
pi_connect(pi);
write_reg(pi, 6, DRIVE(tape));
if (pt_wait(tape, STAT_BUSY | STAT_DRQ, 0, fun, "before command")) {
pi_disconnect(pi);
return -1;
}
write_reg(pi, 4, dlen % 256);
write_reg(pi, 5, dlen / 256);
write_reg(pi, 7, 0xa0); /* ATAPI packet command */
if (pt_wait(tape, STAT_BUSY, STAT_DRQ, fun, "command DRQ")) {
pi_disconnect(pi);
return -1;
}
if (read_reg(pi, 2) != 1) {
printk("%s: %s: command phase error\n", tape->name, fun);
pi_disconnect(pi);
return -1;
}
pi_write_block(pi, cmd, 12);
return 0;
}
static int pt_completion(struct pt_unit *tape, char *buf, char *fun)
{
struct pi_adapter *pi = tape->pi;
int r, s, n, p;
r = pt_wait(tape, STAT_BUSY, STAT_DRQ | STAT_READY | STAT_ERR,
fun, "completion");
if (read_reg(pi, 7) & STAT_DRQ) {
n = (((read_reg(pi, 4) + 256 * read_reg(pi, 5)) +
3) & 0xfffc);
p = read_reg(pi, 2) & 3;
if (p == 0)
pi_write_block(pi, buf, n);
if (p == 2)
pi_read_block(pi, buf, n);
}
s = pt_wait(tape, STAT_BUSY, STAT_READY | STAT_ERR, fun, "data done");
pi_disconnect(pi);
return (r ? r : s);
}
static void pt_req_sense(struct pt_unit *tape, int quiet)
{
char rs_cmd[12] = { ATAPI_REQ_SENSE, 0, 0, 0, 16, 0, 0, 0, 0, 0, 0, 0 };
char buf[16];
int r;
r = pt_command(tape, rs_cmd, 16, "Request sense");
mdelay(1);
if (!r)
pt_completion(tape, buf, "Request sense");
tape->last_sense = -1;
if (!r) {
if (!quiet)
printk("%s: Sense key: %x, ASC: %x, ASQ: %x\n",
tape->name, buf[2] & 0xf, buf[12], buf[13]);
tape->last_sense = (buf[2] & 0xf) | ((buf[12] & 0xff) << 8)
| ((buf[13] & 0xff) << 16);
}
}
static int pt_atapi(struct pt_unit *tape, char *cmd, int dlen, char *buf, char *fun)
{
int r;
r = pt_command(tape, cmd, dlen, fun);
mdelay(1);
if (!r)
r = pt_completion(tape, buf, fun);
if (r)
pt_req_sense(tape, !fun);
return r;
}
static void pt_sleep(int cs)
{
schedule_timeout_interruptible(cs);
}
static int pt_poll_dsc(struct pt_unit *tape, int pause, int tmo, char *msg)
{
struct pi_adapter *pi = tape->pi;
int k, e, s;
k = 0;
e = 0;
s = 0;
while (k < tmo) {
pt_sleep(pause);
k++;
pi_connect(pi);
write_reg(pi, 6, DRIVE(tape));
s = read_reg(pi, 7);
e = read_reg(pi, 1);
pi_disconnect(pi);
if (s & (STAT_ERR | STAT_SEEK))
break;
}
if ((k >= tmo) || (s & STAT_ERR)) {
if (k >= tmo)
printk("%s: %s DSC timeout\n", tape->name, msg);
else
printk("%s: %s stat=0x%x err=0x%x\n", tape->name, msg, s,
e);
pt_req_sense(tape, 0);
return 0;
}
return 1;
}
static void pt_media_access_cmd(struct pt_unit *tape, int tmo, char *cmd, char *fun)
{
if (pt_command(tape, cmd, 0, fun)) {
pt_req_sense(tape, 0);
return;
}
pi_disconnect(tape->pi);
pt_poll_dsc(tape, HZ, tmo, fun);
}
static void pt_rewind(struct pt_unit *tape)
{
char rw_cmd[12] = { ATAPI_REWIND, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 };
pt_media_access_cmd(tape, PT_REWIND_TMO, rw_cmd, "rewind");
}
static void pt_write_fm(struct pt_unit *tape)
{
char wm_cmd[12] = { ATAPI_WFM, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0 };
pt_media_access_cmd(tape, PT_TMO, wm_cmd, "write filemark");
}
#define DBMSG(msg) ((verbose>1)?(msg):NULL)
static int pt_reset(struct pt_unit *tape)
{
struct pi_adapter *pi = tape->pi;
int i, k, flg;
int expect[5] = { 1, 1, 1, 0x14, 0xeb };
pi_connect(pi);
write_reg(pi, 6, DRIVE(tape));
write_reg(pi, 7, 8);
pt_sleep(20 * HZ / 1000);
k = 0;
while ((k++ < PT_RESET_TMO) && (status_reg(pi) & STAT_BUSY))
pt_sleep(HZ / 10);
flg = 1;
for (i = 0; i < 5; i++)
flg &= (read_reg(pi, i + 1) == expect[i]);
if (verbose) {
printk("%s: Reset (%d) signature = ", tape->name, k);
for (i = 0; i < 5; i++)
printk("%3x", read_reg(pi, i + 1));
if (!flg)
printk(" (incorrect)");
printk("\n");
}
pi_disconnect(pi);
return flg - 1;
}
static int pt_ready_wait(struct pt_unit *tape, int tmo)
{
char tr_cmd[12] = { ATAPI_TEST_READY, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 };
int k, p;
k = 0;
while (k < tmo) {
tape->last_sense = 0;
pt_atapi(tape, tr_cmd, 0, NULL, DBMSG("test unit ready"));
p = tape->last_sense;
if (!p)
return 0;
if (!(((p & 0xffff) == 0x0402) || ((p & 0xff) == 6)))
return p;
k++;
pt_sleep(HZ);
}
return 0x000020; /* timeout */
}
static void xs(char *buf, char *targ, int offs, int len)
{
int j, k, l;
j = 0;
l = 0;
for (k = 0; k < len; k++)
if ((buf[k + offs] != 0x20) || (buf[k + offs] != l))
l = targ[j++] = buf[k + offs];
if (l == 0x20)
j--;
targ[j] = 0;
}
static int xn(char *buf, int offs, int size)
{
int v, k;
v = 0;
for (k = 0; k < size; k++)
v = v * 256 + (buf[k + offs] & 0xff);
return v;
}
static int pt_identify(struct pt_unit *tape)
{
int dt, s;
char *ms[2] = { "master", "slave" };
char mf[10], id[18];
char id_cmd[12] = { ATAPI_IDENTIFY, 0, 0, 0, 36, 0, 0, 0, 0, 0, 0, 0 };
char ms_cmd[12] =
{ ATAPI_MODE_SENSE, 0, 0x2a, 0, 36, 0, 0, 0, 0, 0, 0, 0 };
char ls_cmd[12] =
{ ATAPI_LOG_SENSE, 0, 0x71, 0, 0, 0, 0, 0, 36, 0, 0, 0 };
char buf[36];
s = pt_atapi(tape, id_cmd, 36, buf, "identify");
if (s)
return -1;
dt = buf[0] & 0x1f;
if (dt != 1) {
if (verbose)
printk("%s: Drive %d, unsupported type %d\n",
tape->name, tape->drive, dt);
return -1;
}
xs(buf, mf, 8, 8);
xs(buf, id, 16, 16);
tape->flags = 0;
tape->capacity = 0;
tape->bs = 0;
if (!pt_ready_wait(tape, PT_READY_TMO))
tape->flags |= PT_MEDIA;
if (!pt_atapi(tape, ms_cmd, 36, buf, "mode sense")) {
if (!(buf[2] & 0x80))
tape->flags |= PT_WRITE_OK;
tape->bs = xn(buf, 10, 2);
}
if (!pt_atapi(tape, ls_cmd, 36, buf, "log sense"))
tape->capacity = xn(buf, 24, 4);
printk("%s: %s %s, %s", tape->name, mf, id, ms[tape->drive]);
if (!(tape->flags & PT_MEDIA))
printk(", no media\n");
else {
if (!(tape->flags & PT_WRITE_OK))
printk(", RO");
printk(", blocksize %d, %d MB\n", tape->bs, tape->capacity / 1024);
}
return 0;
}
/*
* returns 0, with id set if drive is detected
* -1, if drive detection failed
*/
static int pt_probe(struct pt_unit *tape)
{
if (tape->drive == -1) {
for (tape->drive = 0; tape->drive <= 1; tape->drive++)
if (!pt_reset(tape))
return pt_identify(tape);
} else {
if (!pt_reset(tape))
return pt_identify(tape);
}
return -1;
}
static int pt_detect(void)
{
struct pt_unit *tape;
int specified = 0, found = 0;
int unit;
printk("%s: %s version %s, major %d\n", name, name, PT_VERSION, major);
specified = 0;
for (unit = 0; unit < PT_UNITS; unit++) {
struct pt_unit *tape = &pt[unit];
tape->pi = &tape->pia;
atomic_set(&tape->available, 1);
tape->flags = 0;
tape->last_sense = 0;
tape->present = 0;
tape->bufptr = NULL;
tape->drive = DU[D_SLV];
snprintf(tape->name, PT_NAMELEN, "%s%d", name, unit);
if (!DU[D_PRT])
continue;
specified++;
if (pi_init(tape->pi, 0, DU[D_PRT], DU[D_MOD], DU[D_UNI],
DU[D_PRO], DU[D_DLY], pt_scratch, PI_PT,
verbose, tape->name)) {
if (!pt_probe(tape)) {
tape->present = 1;
found++;
} else
pi_release(tape->pi);
}
}
if (specified == 0) {
tape = pt;
if (pi_init(tape->pi, 1, -1, -1, -1, -1, -1, pt_scratch,
PI_PT, verbose, tape->name)) {
if (!pt_probe(tape)) {
tape->present = 1;
found++;
} else
pi_release(tape->pi);
}
}
if (found)
return 0;
printk("%s: No ATAPI tape drive detected\n", name);
return -1;
}
static int pt_open(struct inode *inode, struct file *file)
{
int unit = iminor(inode) & 0x7F;
struct pt_unit *tape = pt + unit;
int err;
if (unit >= PT_UNITS || (!tape->present))
return -ENODEV;
err = -EBUSY;
if (!atomic_dec_and_test(&tape->available))
goto out;
pt_identify(tape);
err = -ENODEV;
if (!tape->flags & PT_MEDIA)
goto out;
err = -EROFS;
if ((!tape->flags & PT_WRITE_OK) && (file->f_mode & 2))
goto out;
if (!(iminor(inode) & 128))
tape->flags |= PT_REWIND;
err = -ENOMEM;
tape->bufptr = kmalloc(PT_BUFSIZE, GFP_KERNEL);
if (tape->bufptr == NULL) {
printk("%s: buffer allocation failed\n", tape->name);
goto out;
}
file->private_data = tape;
return 0;
out:
atomic_inc(&tape->available);
return err;
}
static int pt_ioctl(struct inode *inode, struct file *file,
unsigned int cmd, unsigned long arg)
{
struct pt_unit *tape = file->private_data;
struct mtop __user *p = (void __user *)arg;
struct mtop mtop;
switch (cmd) {
case MTIOCTOP:
if (copy_from_user(&mtop, p, sizeof(struct mtop)))
return -EFAULT;
switch (mtop.mt_op) {
case MTREW:
pt_rewind(tape);
return 0;
case MTWEOF:
pt_write_fm(tape);
return 0;
default:
printk("%s: Unimplemented mt_op %d\n", tape->name,
mtop.mt_op);
return -EINVAL;
}
default:
printk("%s: Unimplemented ioctl 0x%x\n", tape->name, cmd);
return -EINVAL;
}
}
static int
pt_release(struct inode *inode, struct file *file)
{
struct pt_unit *tape = file->private_data;
if (atomic_read(&tape->available) > 1)
return -EINVAL;
if (tape->flags & PT_WRITING)
pt_write_fm(tape);
if (tape->flags & PT_REWIND)
pt_rewind(tape);
kfree(tape->bufptr);
tape->bufptr = NULL;
atomic_inc(&tape->available);
return 0;
}
static ssize_t pt_read(struct file *filp, char __user *buf, size_t count, loff_t * ppos)
{
struct pt_unit *tape = filp->private_data;
struct pi_adapter *pi = tape->pi;
char rd_cmd[12] = { ATAPI_READ_6, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 };
int k, n, r, p, s, t, b;
if (!(tape->flags & (PT_READING | PT_WRITING))) {
tape->flags |= PT_READING;
if (pt_atapi(tape, rd_cmd, 0, NULL, "start read-ahead"))
return -EIO;
} else if (tape->flags & PT_WRITING)
return -EIO;
if (tape->flags & PT_EOF)
return 0;
t = 0;
while (count > 0) {
if (!pt_poll_dsc(tape, HZ / 100, PT_TMO, "read"))
return -EIO;
n = count;
if (n > 32768)
n = 32768; /* max per command */
b = (n - 1 + tape->bs) / tape->bs;
n = b * tape->bs; /* rounded up to even block */
rd_cmd[4] = b;
r = pt_command(tape, rd_cmd, n, "read");
mdelay(1);
if (r) {
pt_req_sense(tape, 0);
return -EIO;
}
while (1) {
r = pt_wait(tape, STAT_BUSY,
STAT_DRQ | STAT_ERR | STAT_READY,
DBMSG("read DRQ"), "");
if (r & STAT_SENSE) {
pi_disconnect(pi);
pt_req_sense(tape, 0);
return -EIO;
}
if (r)
tape->flags |= PT_EOF;
s = read_reg(pi, 7);
if (!(s & STAT_DRQ))
break;
n = (read_reg(pi, 4) + 256 * read_reg(pi, 5));
p = (read_reg(pi, 2) & 3);
if (p != 2) {
pi_disconnect(pi);
printk("%s: Phase error on read: %d\n", tape->name,
p);
return -EIO;
}
while (n > 0) {
k = n;
if (k > PT_BUFSIZE)
k = PT_BUFSIZE;
pi_read_block(pi, tape->bufptr, k);
n -= k;
b = k;
if (b > count)
b = count;
if (copy_to_user(buf + t, tape->bufptr, b)) {
pi_disconnect(pi);
return -EFAULT;
}
t += b;
count -= b;
}
}
pi_disconnect(pi);
if (tape->flags & PT_EOF)
break;
}
return t;
}
static ssize_t pt_write(struct file *filp, const char __user *buf, size_t count, loff_t * ppos)
{
struct pt_unit *tape = filp->private_data;
struct pi_adapter *pi = tape->pi;
char wr_cmd[12] = { ATAPI_WRITE_6, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 };
int k, n, r, p, s, t, b;
if (!(tape->flags & PT_WRITE_OK))
return -EROFS;
if (!(tape->flags & (PT_READING | PT_WRITING))) {
tape->flags |= PT_WRITING;
if (pt_atapi
(tape, wr_cmd, 0, NULL, "start buffer-available mode"))
return -EIO;
} else if (tape->flags & PT_READING)
return -EIO;
if (tape->flags & PT_EOF)
return -ENOSPC;
t = 0;
while (count > 0) {
if (!pt_poll_dsc(tape, HZ / 100, PT_TMO, "write"))
return -EIO;
n = count;
if (n > 32768)
n = 32768; /* max per command */
b = (n - 1 + tape->bs) / tape->bs;
n = b * tape->bs; /* rounded up to even block */
wr_cmd[4] = b;
r = pt_command(tape, wr_cmd, n, "write");
mdelay(1);
if (r) { /* error delivering command only */
pt_req_sense(tape, 0);
return -EIO;
}
while (1) {
r = pt_wait(tape, STAT_BUSY,
STAT_DRQ | STAT_ERR | STAT_READY,
DBMSG("write DRQ"), NULL);
if (r & STAT_SENSE) {
pi_disconnect(pi);
pt_req_sense(tape, 0);
return -EIO;
}
if (r)
tape->flags |= PT_EOF;
s = read_reg(pi, 7);
if (!(s & STAT_DRQ))
break;
n = (read_reg(pi, 4) + 256 * read_reg(pi, 5));
p = (read_reg(pi, 2) & 3);
if (p != 0) {
pi_disconnect(pi);
printk("%s: Phase error on write: %d \n",
tape->name, p);
return -EIO;
}
while (n > 0) {
k = n;
if (k > PT_BUFSIZE)
k = PT_BUFSIZE;
b = k;
if (b > count)
b = count;
if (copy_from_user(tape->bufptr, buf + t, b)) {
pi_disconnect(pi);
return -EFAULT;
}
pi_write_block(pi, tape->bufptr, k);
t += b;
count -= b;
n -= k;
}
}
pi_disconnect(pi);
if (tape->flags & PT_EOF)
break;
}
return t;
}
static int __init pt_init(void)
{
int unit;
int err;
if (disable) {
err = -EINVAL;
goto out;
}
if (pt_detect()) {
err = -ENODEV;
goto out;
}
err = register_chrdev(major, name, &pt_fops);
if (err < 0) {
printk("pt_init: unable to get major number %d\n", major);
for (unit = 0; unit < PT_UNITS; unit++)
if (pt[unit].present)
pi_release(pt[unit].pi);
goto out;
}
major = err;
pt_class = class_create(THIS_MODULE, "pt");
if (IS_ERR(pt_class)) {
err = PTR_ERR(pt_class);
goto out_chrdev;
}
for (unit = 0; unit < PT_UNITS; unit++)
if (pt[unit].present) {
class_device_create(pt_class, NULL, MKDEV(major, unit),
NULL, "pt%d", unit);
class_device_create(pt_class, NULL, MKDEV(major, unit + 128),
NULL, "pt%dn", unit);
}
goto out;
out_chrdev:
unregister_chrdev(major, "pt");
out:
return err;
}
static void __exit pt_exit(void)
{
int unit;
for (unit = 0; unit < PT_UNITS; unit++)
if (pt[unit].present) {
class_device_destroy(pt_class, MKDEV(major, unit));
class_device_destroy(pt_class, MKDEV(major, unit + 128));
}
class_destroy(pt_class);
unregister_chrdev(major, name);
for (unit = 0; unit < PT_UNITS; unit++)
if (pt[unit].present)
pi_release(pt[unit].pi);
}
MODULE_LICENSE("GPL");
module_init(pt_init)
module_exit(pt_exit)
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