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authorJames Bottomley <JBottomley@Parallels.com>2012-10-02 08:55:12 +0100
committerJames Bottomley <JBottomley@Parallels.com>2012-10-02 08:55:12 +0100
commitfe709ed827d370e6b0c0a9f9456da1c22bdcd118 (patch)
treec5a7fd72a745a5f6656a58acc9a1d277e26f9595 /drivers/scsi/st.c
parent1c4cf1d5845b59cdcbfad8e67272cf5b219ab062 (diff)
parent0644f5393e915f13733bcc65f13195ff39aeb63e (diff)
Merge SCSI misc branch into isci-for-3.6 tag
Diffstat (limited to 'drivers/scsi/st.c')
-rw-r--r--drivers/scsi/st.c416
1 files changed, 172 insertions, 244 deletions
diff --git a/drivers/scsi/st.c b/drivers/scsi/st.c
index e41998cb098..98156a97c47 100644
--- a/drivers/scsi/st.c
+++ b/drivers/scsi/st.c
@@ -37,6 +37,7 @@ static const char *verstr = "20101219";
#include <linux/blkdev.h>
#include <linux/moduleparam.h>
#include <linux/cdev.h>
+#include <linux/idr.h>
#include <linux/delay.h>
#include <linux/mutex.h>
@@ -74,17 +75,14 @@ static const char *verstr = "20101219";
#include "st_options.h"
#include "st.h"
-static DEFINE_MUTEX(st_mutex);
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 st_dev_max;
-static int st_nr_dev;
-
-static struct class *st_sysfs_class;
+static struct class st_sysfs_class;
+static struct device_attribute st_dev_attrs[];
MODULE_AUTHOR("Kai Makisara");
MODULE_DESCRIPTION("SCSI tape (st) driver");
@@ -173,13 +171,9 @@ static int debugging = DEBUG;
24 bits) */
#define SET_DENS_AND_BLK 0x10001
-static DEFINE_RWLOCK(st_dev_arr_lock);
-
static int st_fixed_buffer_size = ST_FIXED_BUFFER_SIZE;
static int st_max_sg_segs = ST_MAX_SG;
-static struct scsi_tape **scsi_tapes = NULL;
-
static int modes_defined;
static int enlarge_buffer(struct st_buffer *, int, int);
@@ -198,7 +192,6 @@ static int st_remove(struct device *);
static int do_create_sysfs_files(void);
static void do_remove_sysfs_files(void);
-static int do_create_class_files(struct scsi_tape *, int, int);
static struct scsi_driver st_template = {
.owner = THIS_MODULE,
@@ -221,6 +214,10 @@ 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);
+
#include "osst_detect.h"
@@ -238,10 +235,9 @@ static struct scsi_tape *scsi_tape_get(int dev)
struct scsi_tape *STp = NULL;
mutex_lock(&st_ref_mutex);
- write_lock(&st_dev_arr_lock);
+ spin_lock(&st_index_lock);
- if (dev < st_dev_max && scsi_tapes != NULL)
- STp = scsi_tapes[dev];
+ STp = idr_find(&st_index_idr, dev);
if (!STp) goto out;
kref_get(&STp->kref);
@@ -258,7 +254,7 @@ out_put:
kref_put(&STp->kref, scsi_tape_release);
STp = NULL;
out:
- write_unlock(&st_dev_arr_lock);
+ spin_unlock(&st_index_lock);
mutex_unlock(&st_ref_mutex);
return STp;
}
@@ -1188,7 +1184,6 @@ static int st_open(struct inode *inode, struct file *filp)
int dev = TAPE_NR(inode);
char *name;
- mutex_lock(&st_mutex);
/*
* 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
@@ -1197,24 +1192,22 @@ static int st_open(struct inode *inode, struct file *filp)
filp->f_mode &= ~(FMODE_PREAD | FMODE_PWRITE);
if (!(STp = scsi_tape_get(dev))) {
- mutex_unlock(&st_mutex);
return -ENXIO;
}
- write_lock(&st_dev_arr_lock);
filp->private_data = STp;
name = tape_name(STp);
+ spin_lock(&st_use_lock);
if (STp->in_use) {
- write_unlock(&st_dev_arr_lock);
+ spin_unlock(&st_use_lock);
scsi_tape_put(STp);
- mutex_unlock(&st_mutex);
DEB( printk(ST_DEB_MSG "%s: Device already in use.\n", name); )
return (-EBUSY);
}
STp->in_use = 1;
- write_unlock(&st_dev_arr_lock);
+ spin_unlock(&st_use_lock);
STp->rew_at_close = STp->autorew_dev = (iminor(inode) & 0x80) == 0;
if (scsi_autopm_get_device(STp->device) < 0) {
@@ -1262,16 +1255,16 @@ static int st_open(struct inode *inode, struct file *filp)
retval = (-EIO);
goto err_out;
}
- mutex_unlock(&st_mutex);
return 0;
err_out:
normalize_buffer(STp->buffer);
+ spin_lock(&st_use_lock);
STp->in_use = 0;
+ spin_unlock(&st_use_lock);
scsi_tape_put(STp);
if (resumed)
scsi_autopm_put_device(STp->device);
- mutex_unlock(&st_mutex);
return retval;
}
@@ -1403,9 +1396,9 @@ static int st_release(struct inode *inode, struct file *filp)
do_door_lock(STp, 0);
normalize_buffer(STp->buffer);
- write_lock(&st_dev_arr_lock);
+ spin_lock(&st_use_lock);
STp->in_use = 0;
- write_unlock(&st_dev_arr_lock);
+ spin_unlock(&st_use_lock);
scsi_autopm_put_device(STp->device);
scsi_tape_put(STp);
@@ -3992,16 +3985,98 @@ static const struct file_operations st_fops =
.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;
+
+ 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;
+ }
+ STm->cdevs[rew] = cdev;
+
+ i = mode << (4 - ST_NBR_MODE_BITS);
+ snprintf(name, 10, "%s%s%s", rew ? "n" : "",
+ tape->disk->disk_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]);
+ STm->cdevs[rew] = NULL;
+out:
+ 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 gendisk *disk = NULL;
- struct cdev *cdev = NULL;
struct scsi_tape *tpnt = NULL;
struct st_modedef *STm;
struct st_partstat *STps;
struct st_buffer *buffer;
- int i, j, mode, dev_num, error;
+ int i, dev_num, error;
char *stp;
if (SDp->type != TYPE_TAPE)
@@ -4028,58 +4103,16 @@ static int st_probe(struct device *dev)
goto out_buffer_free;
}
- write_lock(&st_dev_arr_lock);
- if (st_nr_dev >= st_dev_max) {
- struct scsi_tape **tmp_da;
- int tmp_dev_max;
-
- tmp_dev_max = max(st_nr_dev * 2, 8);
- if (tmp_dev_max > ST_MAX_TAPES)
- tmp_dev_max = ST_MAX_TAPES;
- if (tmp_dev_max <= st_nr_dev) {
- write_unlock(&st_dev_arr_lock);
- printk(KERN_ERR "st: Too many tape devices (max. %d).\n",
- ST_MAX_TAPES);
- goto out_put_disk;
- }
-
- tmp_da = kzalloc(tmp_dev_max * sizeof(struct scsi_tape *), GFP_ATOMIC);
- if (tmp_da == NULL) {
- write_unlock(&st_dev_arr_lock);
- printk(KERN_ERR "st: Can't extend device array.\n");
- goto out_put_disk;
- }
-
- if (scsi_tapes != NULL) {
- memcpy(tmp_da, scsi_tapes,
- st_dev_max * sizeof(struct scsi_tape *));
- kfree(scsi_tapes);
- }
- scsi_tapes = tmp_da;
-
- st_dev_max = tmp_dev_max;
- }
-
- for (i = 0; i < st_dev_max; i++)
- if (scsi_tapes[i] == NULL)
- break;
- if (i >= st_dev_max)
- panic("scsi_devices corrupt (st)");
-
tpnt = kzalloc(sizeof(struct scsi_tape), GFP_ATOMIC);
if (tpnt == NULL) {
- write_unlock(&st_dev_arr_lock);
printk(KERN_ERR "st: Can't allocate device descriptor.\n");
goto out_put_disk;
}
kref_init(&tpnt->kref);
tpnt->disk = disk;
- sprintf(disk->disk_name, "st%d", i);
disk->private_data = &tpnt->driver;
disk->queue = SDp->request_queue;
tpnt->driver = &st_template;
- scsi_tapes[i] = tpnt;
- dev_num = i;
tpnt->device = SDp;
if (SDp->scsi_level <= 2)
@@ -4125,6 +4158,7 @@ static int st_probe(struct device *dev)
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++) {
@@ -4144,38 +4178,34 @@ static int st_probe(struct device *dev)
tpnt->blksize_changed = 0;
mutex_init(&tpnt->lock);
- st_nr_dev++;
- write_unlock(&st_dev_arr_lock);
+ if (!idr_pre_get(&st_index_idr, GFP_KERNEL)) {
+ pr_warn("st: idr expansion failed\n");
+ error = -ENOMEM;
+ goto out_put_disk;
+ }
- for (mode = 0; mode < ST_NBR_MODES; ++mode) {
- STm = &(tpnt->modes[mode]);
- for (j=0; j < 2; j++) {
- cdev = cdev_alloc();
- if (!cdev) {
- printk(KERN_ERR
- "st%d: out of memory. Device not attached.\n",
- dev_num);
- goto out_free_tape;
- }
- cdev->owner = THIS_MODULE;
- cdev->ops = &st_fops;
-
- error = cdev_add(cdev,
- MKDEV(SCSI_TAPE_MAJOR, TAPE_MINOR(dev_num, mode, j)),
- 1);
- if (error) {
- printk(KERN_ERR "st%d: Can't add %s-rewind mode %d\n",
- dev_num, j ? "non" : "auto", mode);
- printk(KERN_ERR "st%d: Device not attached.\n", dev_num);
- goto out_free_tape;
- }
- STm->cdevs[j] = cdev;
+ spin_lock(&st_index_lock);
+ error = idr_get_new(&st_index_idr, tpnt, &dev_num);
+ spin_unlock(&st_index_lock);
+ if (error) {
+ pr_warn("st: idr allocation failed: %d\n", error);
+ goto out_put_disk;
+ }
- }
- error = do_create_class_files(tpnt, dev_num, mode);
- if (error)
- goto out_free_tape;
+ if (dev_num > ST_MAX_TAPES) {
+ pr_err("st: Too many tape devices (max. %d).\n", ST_MAX_TAPES);
+ goto out_put_index;
}
+
+ tpnt->index = dev_num;
+ sprintf(disk->disk_name, "st%d", dev_num);
+
+ 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,
@@ -4186,28 +4216,12 @@ static int st_probe(struct device *dev)
return 0;
-out_free_tape:
- for (mode=0; mode < ST_NBR_MODES; mode++) {
- STm = &(tpnt->modes[mode]);
- sysfs_remove_link(&tpnt->device->sdev_gendev.kobj,
- "tape");
- for (j=0; j < 2; j++) {
- if (STm->cdevs[j]) {
- if (cdev == STm->cdevs[j])
- cdev = NULL;
- device_destroy(st_sysfs_class,
- MKDEV(SCSI_TAPE_MAJOR,
- TAPE_MINOR(i, mode, j)));
- cdev_del(STm->cdevs[j]);
- }
- }
- }
- if (cdev)
- cdev_del(cdev);
- write_lock(&st_dev_arr_lock);
- scsi_tapes[dev_num] = NULL;
- st_nr_dev--;
- write_unlock(&st_dev_arr_lock);
+out_remove_devs:
+ remove_cdevs(tpnt);
+out_put_index:
+ spin_lock(&st_index_lock);
+ idr_remove(&st_index_idr, dev_num);
+ spin_unlock(&st_index_lock);
out_put_disk:
put_disk(disk);
kfree(tpnt);
@@ -4220,38 +4234,18 @@ out:
static int st_remove(struct device *dev)
{
- struct scsi_device *SDp = to_scsi_device(dev);
- struct scsi_tape *tpnt;
- int i, j, mode;
-
- scsi_autopm_get_device(SDp);
- write_lock(&st_dev_arr_lock);
- for (i = 0; i < st_dev_max; i++) {
- tpnt = scsi_tapes[i];
- if (tpnt != NULL && tpnt->device == SDp) {
- scsi_tapes[i] = NULL;
- st_nr_dev--;
- write_unlock(&st_dev_arr_lock);
- sysfs_remove_link(&tpnt->device->sdev_gendev.kobj,
- "tape");
- for (mode = 0; mode < ST_NBR_MODES; ++mode) {
- for (j=0; j < 2; j++) {
- device_destroy(st_sysfs_class,
- MKDEV(SCSI_TAPE_MAJOR,
- TAPE_MINOR(i, mode, j)));
- cdev_del(tpnt->modes[mode].cdevs[j]);
- tpnt->modes[mode].cdevs[j] = NULL;
- }
- }
+ struct scsi_tape *tpnt = dev_get_drvdata(dev);
+ int index = tpnt->index;
- mutex_lock(&st_ref_mutex);
- kref_put(&tpnt->kref, scsi_tape_release);
- mutex_unlock(&st_ref_mutex);
- return 0;
- }
- }
+ scsi_autopm_get_device(to_scsi_device(dev));
+ remove_cdevs(tpnt);
- write_unlock(&st_dev_arr_lock);
+ 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;
}
@@ -4283,6 +4277,11 @@ static void scsi_tape_release(struct kref *kref)
return;
}
+static struct class st_sysfs_class = {
+ .name = "scsi_tape",
+ .dev_attrs = st_dev_attrs,
+};
+
static int __init init_st(void)
{
int err;
@@ -4292,10 +4291,10 @@ static int __init init_st(void)
printk(KERN_INFO "st: Version %s, fixed bufsize %d, s/g segs %d\n",
verstr, st_fixed_buffer_size, st_max_sg_segs);
- st_sysfs_class = class_create(THIS_MODULE, "scsi_tape");
- if (IS_ERR(st_sysfs_class)) {
- printk(KERN_ERR "Unable create sysfs class for SCSI tapes\n");
- return PTR_ERR(st_sysfs_class);
+ 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),
@@ -4322,7 +4321,7 @@ err_chrdev:
unregister_chrdev_region(MKDEV(SCSI_TAPE_MAJOR, 0),
ST_MAX_TAPE_ENTRIES);
err_class:
- class_destroy(st_sysfs_class);
+ class_unregister(&st_sysfs_class);
return err;
}
@@ -4332,8 +4331,7 @@ 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_destroy(st_sysfs_class);
- kfree(scsi_tapes);
+ class_unregister(&st_sysfs_class);
printk(KERN_INFO "st: Unloaded.\n");
}
@@ -4405,10 +4403,9 @@ static void do_remove_sysfs_files(void)
driver_remove_file(sysfs, &driver_attr_try_direct_io);
}
-
/* The sysfs simple class interface */
static ssize_t
-st_defined_show(struct device *dev, struct device_attribute *attr, char *buf)
+defined_show(struct device *dev, struct device_attribute *attr, char *buf)
{
struct st_modedef *STm = dev_get_drvdata(dev);
ssize_t l = 0;
@@ -4417,10 +4414,9 @@ st_defined_show(struct device *dev, struct device_attribute *attr, char *buf)
return l;
}
-DEVICE_ATTR(defined, S_IRUGO, st_defined_show, NULL);
-
static ssize_t
-st_defblk_show(struct device *dev, struct device_attribute *attr, char *buf)
+default_blksize_show(struct device *dev, struct device_attribute *attr,
+ char *buf)
{
struct st_modedef *STm = dev_get_drvdata(dev);
ssize_t l = 0;
@@ -4429,10 +4425,10 @@ st_defblk_show(struct device *dev, struct device_attribute *attr, char *buf)
return l;
}
-DEVICE_ATTR(default_blksize, S_IRUGO, st_defblk_show, NULL);
static ssize_t
-st_defdensity_show(struct device *dev, struct device_attribute *attr, char *buf)
+default_density_show(struct device *dev, struct device_attribute *attr,
+ char *buf)
{
struct st_modedef *STm = dev_get_drvdata(dev);
ssize_t l = 0;
@@ -4443,11 +4439,9 @@ st_defdensity_show(struct device *dev, struct device_attribute *attr, char *buf)
return l;
}
-DEVICE_ATTR(default_density, S_IRUGO, st_defdensity_show, NULL);
-
static ssize_t
-st_defcompression_show(struct device *dev, struct device_attribute *attr,
- char *buf)
+default_compression_show(struct device *dev, struct device_attribute *attr,
+ char *buf)
{
struct st_modedef *STm = dev_get_drvdata(dev);
ssize_t l = 0;
@@ -4456,28 +4450,14 @@ st_defcompression_show(struct device *dev, struct device_attribute *attr,
return l;
}
-DEVICE_ATTR(default_compression, S_IRUGO, st_defcompression_show, NULL);
-
static ssize_t
-st_options_show(struct device *dev, struct device_attribute *attr, char *buf)
+options_show(struct device *dev, struct device_attribute *attr, char *buf)
{
struct st_modedef *STm = dev_get_drvdata(dev);
- struct scsi_tape *STp;
- int i, j, options;
+ struct scsi_tape *STp = STm->tape;
+ int options;
ssize_t l = 0;
- for (i=0; i < st_dev_max; i++) {
- for (j=0; j < ST_NBR_MODES; j++)
- if (&scsi_tapes[i]->modes[j] == STm)
- break;
- if (j < ST_NBR_MODES)
- break;
- }
- if (i == st_dev_max)
- return 0; /* should never happen */
-
- STp = scsi_tapes[i];
-
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;
@@ -4498,66 +4478,14 @@ st_options_show(struct device *dev, struct device_attribute *attr, char *buf)
return l;
}
-DEVICE_ATTR(options, S_IRUGO, st_options_show, NULL);
-
-static int do_create_class_files(struct scsi_tape *STp, int dev_num, int mode)
-{
- int i, rew, error;
- char name[10];
- struct device *st_class_member;
-
- for (rew=0; rew < 2; rew++) {
- /* Make sure that the minor numbers corresponding to the four
- first modes always get the same names */
- i = mode << (4 - ST_NBR_MODE_BITS);
- snprintf(name, 10, "%s%s%s", rew ? "n" : "",
- STp->disk->disk_name, st_formats[i]);
- st_class_member =
- device_create(st_sysfs_class, &STp->device->sdev_gendev,
- MKDEV(SCSI_TAPE_MAJOR,
- TAPE_MINOR(dev_num, mode, rew)),
- &STp->modes[mode], "%s", name);
- if (IS_ERR(st_class_member)) {
- printk(KERN_WARNING "st%d: device_create failed\n",
- dev_num);
- error = PTR_ERR(st_class_member);
- goto out;
- }
-
- error = device_create_file(st_class_member,
- &dev_attr_defined);
- if (error) goto out;
- error = device_create_file(st_class_member,
- &dev_attr_default_blksize);
- if (error) goto out;
- error = device_create_file(st_class_member,
- &dev_attr_default_density);
- if (error) goto out;
- error = device_create_file(st_class_member,
- &dev_attr_default_compression);
- if (error) goto out;
- error = device_create_file(st_class_member,
- &dev_attr_options);
- if (error) goto out;
-
- if (mode == 0 && rew == 0) {
- error = sysfs_create_link(&STp->device->sdev_gendev.kobj,
- &st_class_member->kobj,
- "tape");
- if (error) {
- printk(KERN_ERR
- "st%d: Can't create sysfs link from SCSI device.\n",
- dev_num);
- goto out;
- }
- }
- }
-
- return 0;
-
-out:
- return error;
-}
+static struct device_attribute st_dev_attrs[] = {
+ __ATTR_RO(defined),
+ __ATTR_RO(default_blksize),
+ __ATTR_RO(default_density),
+ __ATTR_RO(default_compression),
+ __ATTR_RO(options),
+ __ATTR_NULL,
+};
/* The following functions may be useful for a larger audience. */
static int sgl_map_user_pages(struct st_buffer *STbp,