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ide: fix refcounting in device drivers

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During host driver module removal del_gendisk() results in a final
put on drive->gendev and freeing the drive by drive_release_dev().

Convert device drivers from using struct kref to use struct device
so device driver's object holds reference on ->gendev and prevents
drive from prematurely going away.

Also fix ->remove methods to not erroneously drop reference on a
host driver by using only put_device() instead of ide*_put().

Reported-by: Stanislaw Gruszka <stf_xl@wp.pl>
Tested-by: Stanislaw Gruszka <stf_xl@wp.pl>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
This commit is contained in:
Bartlomiej Zolnierkiewicz 2009-02-25 20:28:24 +01:00
parent d3dd7107f4
commit 8fed436841
6 changed files with 57 additions and 31 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

27
drivers/ide/ide-cd.c
View file

@ -55,7 +55,7 @@
static DEFINE_MUTEX(idecd_ref_mutex);
static void ide_cd_release(struct kref *);
static void ide_cd_release(struct device *);
static struct cdrom_info *ide_cd_get(struct gendisk *disk)
{
@ -67,7 +67,7 @@ static struct cdrom_info *ide_cd_get(struct gendisk *disk)
if (ide_device_get(cd->drive))
cd = NULL;
else
kref_get(&cd->kref);
get_device(&cd->dev);
}
mutex_unlock(&idecd_ref_mutex);
@ -79,7 +79,7 @@ static void ide_cd_put(struct cdrom_info *cd)
ide_drive_t *drive = cd->drive;
mutex_lock(&idecd_ref_mutex);
kref_put(&cd->kref, ide_cd_release);
put_device(&cd->dev);
ide_device_put(drive);
mutex_unlock(&idecd_ref_mutex);
}
@ -1798,15 +1798,17 @@ static void ide_cd_remove(ide_drive_t *drive)
ide_debug_log(IDE_DBG_FUNC, "Call %s\n", __func__);
ide_proc_unregister_driver(drive, info->driver);
device_del(&info->dev);
del_gendisk(info->disk);
ide_cd_put(info);
mutex_lock(&idecd_ref_mutex);
put_device(&info->dev);
mutex_unlock(&idecd_ref_mutex);
}
static void ide_cd_release(struct kref *kref)
static void ide_cd_release(struct device *dev)
{
struct cdrom_info *info = to_ide_drv(kref, cdrom_info);
struct cdrom_info *info = to_ide_drv(dev, cdrom_info);
struct cdrom_device_info *devinfo = &info->devinfo;
ide_drive_t *drive = info->drive;
struct gendisk *g = info->disk;
@ -2005,7 +2007,12 @@ static int ide_cd_probe(ide_drive_t *drive)
ide_init_disk(g, drive);
kref_init(&info->kref);
info->dev.parent = &drive->gendev;
info->dev.release = ide_cd_release;
dev_set_name(&info->dev, dev_name(&drive->gendev));
if (device_register(&info->dev))
goto out_free_disk;
info->drive = drive;
info->driver = &ide_cdrom_driver;
@ -2019,7 +2026,7 @@ static int ide_cd_probe(ide_drive_t *drive)
g->driverfs_dev = &drive->gendev;
g->flags = GENHD_FL_CD | GENHD_FL_REMOVABLE;
if (ide_cdrom_setup(drive)) {
ide_cd_release(&info->kref);
put_device(&info->dev);
goto failed;
}
@ -2029,6 +2036,8 @@ static int ide_cd_probe(ide_drive_t *drive)
add_disk(g);
return 0;
out_free_disk:
put_disk(g);
out_free_cd:
kfree(info);
failed:

2
drivers/ide/ide-cd.h
View file

@ -80,7 +80,7 @@ struct cdrom_info {
ide_drive_t *drive;
struct ide_driver *driver;
struct gendisk *disk;
struct kref kref;
struct device dev;
/* Buffer for table of contents. NULL if we haven't allocated
a TOC buffer for this device yet. */

26
drivers/ide/ide-gd.c
View file

@ -25,7 +25,7 @@ module_param(debug_mask, ulong, 0644);
static DEFINE_MUTEX(ide_disk_ref_mutex);
static void ide_disk_release(struct kref *);
static void ide_disk_release(struct device *);
static struct ide_disk_obj *ide_disk_get(struct gendisk *disk)
{
@ -37,7 +37,7 @@ static struct ide_disk_obj *ide_disk_get(struct gendisk *disk)
if (ide_device_get(idkp->drive))
idkp = NULL;
else
kref_get(&idkp->kref);
get_device(&idkp->dev);
}
mutex_unlock(&ide_disk_ref_mutex);
return idkp;
@ -48,7 +48,7 @@ static void ide_disk_put(struct ide_disk_obj *idkp)
ide_drive_t *drive = idkp->drive;
mutex_lock(&ide_disk_ref_mutex);
kref_put(&idkp->kref, ide_disk_release);
put_device(&idkp->dev);
ide_device_put(drive);
mutex_unlock(&ide_disk_ref_mutex);
}
@ -66,17 +66,18 @@ static void ide_gd_remove(ide_drive_t *drive)
struct gendisk *g = idkp->disk;
ide_proc_unregister_driver(drive, idkp->driver);
device_del(&idkp->dev);
del_gendisk(g);
drive->disk_ops->flush(drive);
ide_disk_put(idkp);
mutex_lock(&ide_disk_ref_mutex);
put_device(&idkp->dev);
mutex_unlock(&ide_disk_ref_mutex);
}
static void ide_disk_release(struct kref *kref)
static void ide_disk_release(struct device *dev)
{
struct ide_disk_obj *idkp = to_ide_drv(kref, ide_disk_obj);
struct ide_disk_obj *idkp = to_ide_drv(dev, ide_disk_obj);
ide_drive_t *drive = idkp->drive;
struct gendisk *g = idkp->disk;
@ -348,7 +349,12 @@ static int ide_gd_probe(ide_drive_t *drive)
ide_init_disk(g, drive);
kref_init(&idkp->kref);
idkp->dev.parent = &drive->gendev;
idkp->dev.release = ide_disk_release;
dev_set_name(&idkp->dev, dev_name(&drive->gendev));
if (device_register(&idkp->dev))
goto out_free_disk;
idkp->drive = drive;
idkp->driver = &ide_gd_driver;
@ -373,6 +379,8 @@ static int ide_gd_probe(ide_drive_t *drive)
add_disk(g);
return 0;
out_free_disk:
put_disk(g);
out_free_idkp:
kfree(idkp);
failed:

2
drivers/ide/ide-gd.h
View file

@ -17,7 +17,7 @@ struct ide_disk_obj {
ide_drive_t *drive;
struct ide_driver *driver;
struct gendisk *disk;
struct kref kref;
struct device dev;
unsigned int openers; /* protected by BKL for now */
/* Last failed packet command */

29
drivers/ide/ide-tape.c
View file

@ -169,7 +169,7 @@ typedef struct ide_tape_obj {
ide_drive_t *drive;
struct ide_driver *driver;
struct gendisk *disk;
struct kref kref;
struct device dev;
/*
* failed_pc points to the last failed packet command, or contains
@ -267,7 +267,7 @@ static DEFINE_MUTEX(idetape_ref_mutex);
static struct class *idetape_sysfs_class;
static void ide_tape_release(struct kref *);
static void ide_tape_release(struct device *);
static struct ide_tape_obj *ide_tape_get(struct gendisk *disk)
{
@ -279,7 +279,7 @@ static struct ide_tape_obj *ide_tape_get(struct gendisk *disk)
if (ide_device_get(tape->drive))
tape = NULL;
else
kref_get(&tape->kref);
get_device(&tape->dev);
}
mutex_unlock(&idetape_ref_mutex);
return tape;
@ -290,7 +290,7 @@ static void ide_tape_put(struct ide_tape_obj *tape)
ide_drive_t *drive = tape->drive;
mutex_lock(&idetape_ref_mutex);
kref_put(&tape->kref, ide_tape_release);
put_device(&tape->dev);
ide_device_put(drive);
mutex_unlock(&idetape_ref_mutex);
}
@ -308,7 +308,7 @@ static struct ide_tape_obj *ide_tape_chrdev_get(unsigned int i)
mutex_lock(&idetape_ref_mutex);
tape = idetape_devs[i];
if (tape)
kref_get(&tape->kref);
get_device(&tape->dev);
mutex_unlock(&idetape_ref_mutex);
return tape;
}
@ -2256,15 +2256,17 @@ 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);
ide_tape_put(tape);
mutex_lock(&idetape_ref_mutex);
put_device(&tape->dev);
mutex_unlock(&idetape_ref_mutex);
}
static void ide_tape_release(struct kref *kref)
static void ide_tape_release(struct device *dev)
{
struct ide_tape_obj *tape = to_ide_drv(kref, ide_tape_obj);
struct ide_tape_obj *tape = to_ide_drv(dev, ide_tape_obj);
ide_drive_t *drive = tape->drive;
struct gendisk *g = tape->disk;
@ -2407,7 +2409,12 @@ static int ide_tape_probe(ide_drive_t *drive)
ide_init_disk(g, drive);
kref_init(&tape->kref);
tape->dev.parent = &drive->gendev;
tape->dev.release = ide_tape_release;
dev_set_name(&tape->dev, dev_name(&drive->gendev));
if (device_register(&tape->dev))
goto out_free_disk;
tape->drive = drive;
tape->driver = &idetape_driver;
@ -2436,6 +2443,8 @@ static int ide_tape_probe(ide_drive_t *drive)
return 0;
out_free_disk:
put_disk(g);
out_free_tape:
kfree(tape);
failed:

2
include/linux/ide.h
View file

@ -663,7 +663,7 @@ typedef struct ide_drive_s ide_drive_t;
#define to_ide_device(dev) container_of(dev, ide_drive_t, gendev)
#define to_ide_drv(obj, cont_type) \
container_of(obj, struct cont_type, kref)
container_of(obj, struct cont_type, dev)
#define ide_drv_g(disk, cont_type) \
container_of((disk)->private_data, struct cont_type, driver)