From: Kai Makisara <Kai.Makisara@kolumbus.fi>
The patch fixes the following problems:
- cdev allocation moved outside st_dev_arr_lock, prevents the debugging
error messages reported by Mike and Mike
- cdev_unmap() added before cdev_del(), prevents oops (and kernel data
corruption) in case someone tries to use a device after removing the
module
- better error handling for failures in cdev allocation
---
drivers/scsi/st.c | 112 +++++++++++++++++++++++++++++++-----------------------
1 files changed, 66 insertions(+), 46 deletions(-)
diff -puN drivers/scsi/st.c~scsi-tape-fixes drivers/scsi/st.c
--- 25/drivers/scsi/st.c~scsi-tape-fixes 2004-01-24 01:00:26.000000000 -0800
+++ 25-akpm/drivers/scsi/st.c 2004-01-24 01:00:26.000000000 -0800
@@ -9,7 +9,7 @@
Steve Hirsch, Andreas Koppenh"ofer, Michael Leodolter, Eyal Lebedinsky,
Michael Schaefer, J"org Weule, and Eric Youngdale.
- Copyright 1992 - 2003 Kai Makisara
+ Copyright 1992 - 2004 Kai Makisara
email Kai.Makisara@kolumbus.fi
Some small formal changes - aeb, 950809
@@ -17,7 +17,7 @@
Last modified: 18-JAN-1998 Richard Gooch <rgooch@atnf.csiro.au> Devfs support
*/
-static char *verstr = "20031228";
+static char *verstr = "20040122";
#include <linux/module.h>
@@ -3846,27 +3846,53 @@ 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 */
+ }
+
+ for (i = 0; i < ST_NBR_PARTITIONS; i++) {
+ STps = &(tpnt->ps[i]);
+ STps->rw = ST_IDLE;
+ STps->eof = ST_NOEOF;
+ STps->at_sm = 0;
+ STps->last_block_valid = FALSE;
+ STps->drv_block = (-1);
+ STps->drv_file = (-1);
+ }
+
+ tpnt->current_mode = 0;
+ tpnt->modes[0].defined = TRUE;
+ tpnt->density_changed = tpnt->compression_changed =
+ tpnt->blksize_changed = FALSE;
+ init_MUTEX(&tpnt->lock);
+
+ st_nr_dev++;
+ write_unlock(&st_dev_arr_lock);
+
+ 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: out of memory. Device not attached.\n");
- goto out_put_disk;
+ "st%d: out of memory. Device not attached.\n",
+ dev_num);
+ goto out_free_tape;
}
snprintf(cdev->kobj.name, KOBJ_NAME_LEN, "%sm%d%s", disk->disk_name,
- i, j ? "n" : "");
+ mode, j ? "n" : "");
cdev->owner = THIS_MODULE;
cdev->ops = &st_fops;
- STm->cdevs[j] = cdev;
- error = cdev_add(STm->cdevs[j],
- MKDEV(SCSI_TAPE_MAJOR, TAPE_MINOR(dev_num, i, j)),
+ 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", i);
+ 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;
error = sysfs_create_link(&STm->cdevs[j]->kobj, &SDp->sdev_gendev.kobj,
"device");
@@ -3884,35 +3910,15 @@ static int st_probe(struct device *dev)
dev_num);
}
- for (i = 0; i < ST_NBR_PARTITIONS; i++) {
- STps = &(tpnt->ps[i]);
- STps->rw = ST_IDLE;
- STps->eof = ST_NOEOF;
- STps->at_sm = 0;
- STps->last_block_valid = FALSE;
- STps->drv_block = (-1);
- STps->drv_file = (-1);
- }
-
- tpnt->current_mode = 0;
- tpnt->modes[0].defined = TRUE;
-
- tpnt->density_changed = tpnt->compression_changed =
- tpnt->blksize_changed = FALSE;
- init_MUTEX(&tpnt->lock);
-
- st_nr_dev++;
- write_unlock(&st_dev_arr_lock);
-
for (mode = 0; mode < ST_NBR_MODES; ++mode) {
- /* Rewind entry */
- devfs_mk_cdev(MKDEV(SCSI_TAPE_MAJOR, dev_num + (mode << 5)),
- S_IFCHR | S_IRUGO | S_IWUGO,
- "%s/mt%s", SDp->devfs_name, st_formats[mode]);
- /* No-rewind entry */
- devfs_mk_cdev(MKDEV(SCSI_TAPE_MAJOR, dev_num + (mode << 5) + 128),
- S_IFCHR | S_IRUGO | S_IWUGO,
- "%s/mt%sn", SDp->devfs_name, st_formats[mode]);
+ /* Rewind entry */
+ devfs_mk_cdev(MKDEV(SCSI_TAPE_MAJOR, dev_num + (mode << 5)),
+ S_IFCHR | S_IRUGO | S_IWUGO,
+ "%s/mt%s", SDp->devfs_name, st_formats[mode]);
+ /* No-rewind entry */
+ devfs_mk_cdev(MKDEV(SCSI_TAPE_MAJOR, dev_num + (mode << 5) + 128),
+ S_IFCHR | S_IRUGO | S_IWUGO,
+ "%s/mt%sn", SDp->devfs_name, st_formats[mode]);
}
disk->number = devfs_register_tape(SDp->devfs_name);
@@ -3924,18 +3930,30 @@ static int st_probe(struct device *dev)
return 0;
+out_free_tape:
+ for (mode=0; mode < ST_NBR_MODES; mode++) {
+ STm = &(tpnt->modes[mode]);
+ for (j=0; j < 2; j++) {
+ if (STm->cdevs[j]) {
+ if (cdev == STm->cdevs[j])
+ cdev = NULL;
+ sysfs_remove_link(&STm->cdevs[j]->kobj, "device");
+ cdev_unmap(MKDEV(SCSI_TAPE_MAJOR,
+ TAPE_MINOR(dev_num, mode, j)), 1);
+ cdev_del(STm->cdevs[j]);
+ }
+ }
+ }
+ if (cdev)
+ kobject_put(&cdev->kobj);
+ write_lock(&st_dev_arr_lock);
+ scsi_tapes[dev_num] = NULL;
+ st_nr_dev--;
+ write_unlock(&st_dev_arr_lock);
out_put_disk:
put_disk(disk);
- if (tpnt) {
- for (i=0; i < ST_NBR_MODES; i++) {
- STm = &(tpnt->modes[i]);
- if (STm->cdevs[0])
- kobject_put(&STm->cdevs[0]->kobj);
- if (STm->cdevs[1])
- kobject_put(&STm->cdevs[1]->kobj);
- }
+ if (tpnt)
kfree(tpnt);
- }
out_buffer_free:
kfree(buffer);
out:
@@ -3964,6 +3982,8 @@ static int st_remove(struct device *dev)
for (j=0; j < 2; j++) {
sysfs_remove_link(&tpnt->modes[mode].cdevs[j]->kobj,
"device");
+ cdev_unmap(MKDEV(SCSI_TAPE_MAJOR,
+ TAPE_MINOR(i, mode, j)), 1);
cdev_del(tpnt->modes[mode].cdevs[j]);
tpnt->modes[mode].cdevs[j] = NULL;
}
_