From: Mike Anderson <andmike@us.ibm.com>
To: linux-scsi@vger.kernel.org
Subject: [PATCH] scsi host / scsi device ref counting take 2 [3/3]
Date: Fri, 1 Aug 2003 13:26:54 -0700 [thread overview]
Message-ID: <20030801202654.GG3868@beaverton.ibm.com> (raw)
In-Reply-To: <20030801202541.GF3868@beaverton.ibm.com>
-andmike
--
Michael Anderson
andmike@us.ibm.com
DESC
This is a cleanup patch for scsi_device removal.
- Addition of sdev_state member to the scsi_device strucuture to contain
"state" of the device instance.
- Added SDEV_ADD, SDEV_DEL, SDEV_CANCEL, SDEV_RECOVERY states for a scsi
device
- Built on previous patch that renamed scsi_set_device_offline to
scsi_device_cancel to use SDEV_CANCEL value.
- Usage of the sdev_state member to stop scsi_device_get's and final cleanup
on access_count going to zero.
- Added newer release functions and reordered scsi device sysfs unregister.
EDESC
drivers/scsi/scsi.c | 36 +++++++++++++++++++----
drivers/scsi/scsi_priv.h | 1
drivers/scsi/scsi_scan.c | 4 +-
drivers/scsi/scsi_sysfs.c | 70 ++++++++++++++++++++++++++++++++++-----------
include/scsi/scsi_device.h | 15 +++++++++
5 files changed, 100 insertions(+), 26 deletions(-)
diff -puN drivers/scsi/scsi.c~sdev_state drivers/scsi/scsi.c
--- patched-scsi-misc-2.5/drivers/scsi/scsi.c~sdev_state Fri Aug 1 07:07:20 2003
+++ patched-scsi-misc-2.5-andmike/drivers/scsi/scsi.c Fri Aug 1 07:07:20 2003
@@ -893,17 +893,41 @@ int scsi_track_queue_full(struct scsi_de
int scsi_device_get(struct scsi_device *sdev)
{
- if (!try_module_get(sdev->host->hostt->module))
- return -ENXIO;
+ struct class *class = class_get(&sdev_class);
+ int error = -ENXIO;
- sdev->access_count++;
- return 0;
+ if (class) {
+ down_write(&class->subsys.rwsem);
+ if (!test_bit(SDEV_DEL, &sdev->sdev_state))
+ if (try_module_get(sdev->host->hostt->module))
+ if (get_device(&sdev->sdev_gendev)) {
+ sdev->access_count++;
+ error = 0;
+ }
+ up_write(&class->subsys.rwsem);
+ class_put(&sdev_class);
+ }
+
+ return error;
}
void scsi_device_put(struct scsi_device *sdev)
{
- sdev->access_count--;
+ struct class *class = class_get(&sdev_class);
+
+ if (!class)
+ return;
+
+ down_write(&class->subsys.rwsem);
module_put(sdev->host->hostt->module);
+ if (--sdev->access_count == 0) {
+ if (test_bit(SDEV_DEL, &sdev->sdev_state))
+ device_del(&sdev->sdev_gendev);
+ }
+ put_device(&sdev->sdev_gendev);
+ up_write(&class->subsys.rwsem);
+
+ class_put(&sdev_class);
}
int scsi_device_cancel_cb(struct device *dev, void *data)
@@ -927,7 +951,7 @@ int scsi_device_cancel(struct scsi_devic
struct list_head *lh, *lh_sf;
unsigned long flags;
- sdev->online = 0;
+ set_bit(SDEV_CANCEL, &sdev->sdev_state);
spin_lock_irqsave(&sdev->list_lock, flags);
list_for_each_entry(scmd, &sdev->cmd_list, list) {
diff -puN drivers/scsi/scsi_priv.h~sdev_state drivers/scsi/scsi_priv.h
--- patched-scsi-misc-2.5/drivers/scsi/scsi_priv.h~sdev_state Fri Aug 1 07:07:20 2003
+++ patched-scsi-misc-2.5-andmike/drivers/scsi/scsi_priv.h Fri Aug 1 07:07:20 2003
@@ -121,6 +121,7 @@ extern int scsi_sysfs_register(void);
extern void scsi_sysfs_unregister(void);
extern struct class shost_class;
+extern struct class sdev_class;
extern struct bus_type scsi_bus_type;
#endif /* _SCSI_PRIV_H */
diff -puN drivers/scsi/scsi_scan.c~sdev_state drivers/scsi/scsi_scan.c
--- patched-scsi-misc-2.5/drivers/scsi/scsi_scan.c~sdev_state Fri Aug 1 07:07:20 2003
+++ patched-scsi-misc-2.5-andmike/drivers/scsi/scsi_scan.c Fri Aug 1 07:38:00 2003
@@ -288,8 +288,6 @@ void scsi_free_sdev(struct scsi_device *
if (sdev->request_queue)
scsi_free_queue(sdev->request_queue);
- if (sdev->host->hostt->slave_destroy)
- sdev->host->hostt->slave_destroy(sdev);
if (sdev->inquiry)
kfree(sdev->inquiry);
spin_lock_irqsave(sdev->host->host_lock, flags);
@@ -1076,6 +1074,8 @@ struct scsi_device *scsi_add_device(stru
int scsi_remove_device(struct scsi_device *sdev)
{
+ if (sdev->host->hostt->slave_destroy)
+ sdev->host->hostt->slave_destroy(sdev);
scsi_device_unregister(sdev);
return 0;
}
diff -puN drivers/scsi/scsi_sysfs.c~sdev_state drivers/scsi/scsi_sysfs.c
--- patched-scsi-misc-2.5/drivers/scsi/scsi_sysfs.c~sdev_state Fri Aug 1 07:07:20 2003
+++ patched-scsi-misc-2.5-andmike/drivers/scsi/scsi_sysfs.c Fri Aug 1 07:30:58 2003
@@ -78,8 +78,28 @@ struct class shost_class = {
.release = scsi_host_cls_release,
};
-static struct class sdev_class = {
+static void scsi_device_cls_release(struct class_device *class_dev)
+{
+ struct scsi_device *sdev;
+
+ sdev = class_to_sdev(class_dev);
+ put_device(&sdev->sdev_gendev);
+}
+
+static void scsi_device_dev_release(struct device *dev)
+{
+ struct scsi_device *sdev;
+ struct device *parent;
+
+ parent = dev->parent;
+ sdev = to_scsi_device(dev);
+ scsi_free_sdev(sdev);
+ put_device(parent);
+}
+
+struct class sdev_class = {
.name = "scsi_device",
+ .release = scsi_device_cls_release,
};
/* all probing is done in the individual ->probe routines */
@@ -129,7 +149,7 @@ void scsi_sysfs_unregister(void)
*/
#define sdev_show_function(field, format_string) \
static ssize_t \
-show_##field (struct device *dev, char *buf) \
+sdev_show_##field (struct device *dev, char *buf) \
{ \
struct scsi_device *sdev; \
sdev = to_scsi_device(dev); \
@@ -142,7 +162,7 @@ show_##field (struct device *dev, char *
*/
#define sdev_rd_attr(field, format_string) \
sdev_show_function(field, format_string) \
-static DEVICE_ATTR(field, S_IRUGO, show_##field, NULL)
+static DEVICE_ATTR(field, S_IRUGO, sdev_show_##field, NULL)
/*
@@ -160,7 +180,7 @@ sdev_store_##field (struct device *dev,
snscanf (buf, 20, format_string, &sdev->field); \
return count; \
} \
-static DEVICE_ATTR(field, S_IRUGO | S_IWUSR, show_##field, sdev_store_##field)
+static DEVICE_ATTR(field, S_IRUGO | S_IWUSR, sdev_show_##field, sdev_store_##field)
/*
* sdev_rd_attr: create a function and attribute variable for a
@@ -182,7 +202,7 @@ sdev_store_##field (struct device *dev,
} \
return ret; \
} \
-static DEVICE_ATTR(field, S_IRUGO | S_IWUSR, show_##field, sdev_store_##field)
+static DEVICE_ATTR(field, S_IRUGO | S_IWUSR, sdev_show_##field, sdev_store_##field)
/*
* scsi_sdev_check_buf_bit: return 0 if buf is "0", return 1 if buf is "1",
@@ -238,15 +258,6 @@ static struct device_attribute *scsi_sys
NULL
};
-static void scsi_device_release(struct device *dev)
-{
- struct scsi_device *sdev;
-
- sdev = to_scsi_device(dev);
- if (!sdev)
- return;
- scsi_free_sdev(sdev);
-}
static struct device_attribute *attr_overridden(
struct device_attribute **attrs,
@@ -295,12 +306,13 @@ int scsi_device_register(struct scsi_dev
{
int error = 0, i;
+ set_bit(SDEV_ADD, &sdev->sdev_state);
device_initialize(&sdev->sdev_gendev);
sprintf(sdev->sdev_gendev.bus_id,"%d:%d:%d:%d",
sdev->host->host_no, sdev->channel, sdev->id, sdev->lun);
sdev->sdev_gendev.parent = &sdev->host->shost_gendev;
sdev->sdev_gendev.bus = &scsi_bus_type;
- sdev->sdev_gendev.release = scsi_device_release;
+ sdev->sdev_gendev.release = scsi_device_dev_release;
class_device_initialize(&sdev->sdev_classdev);
sdev->sdev_classdev.dev = &sdev->sdev_gendev;
@@ -313,13 +325,18 @@ int scsi_device_register(struct scsi_dev
printk(KERN_INFO "error 1\n");
return error;
}
+
+ get_device(sdev->sdev_gendev.parent);
+
error = class_device_add(&sdev->sdev_classdev);
if (error) {
printk(KERN_INFO "error 2\n");
- device_unregister(&sdev->sdev_gendev);
+ goto clean_device;
return error;
}
+ get_device(&sdev->sdev_gendev);
+
if (sdev->host->hostt->sdev_attrs) {
for (i = 0; sdev->host->hostt->sdev_attrs[i]; i++) {
error = attr_add(&sdev->sdev_gendev,
@@ -340,6 +357,12 @@ int scsi_device_register(struct scsi_dev
}
return error;
+
+clean_device:
+ device_del(&sdev->sdev_gendev);
+ put_device(&sdev->sdev_gendev);
+ return error;
+
}
/**
@@ -348,8 +371,21 @@ int scsi_device_register(struct scsi_dev
**/
void scsi_device_unregister(struct scsi_device *sdev)
{
+ struct class *class = class_get(&sdev_class);
+
class_device_unregister(&sdev->sdev_classdev);
- device_unregister(&sdev->sdev_gendev);
+
+ if (class) {
+ down_write(&class->subsys.rwsem);
+ set_bit(SDEV_DEL, &sdev->sdev_state);
+ if (sdev->access_count == 0)
+ device_del(&sdev->sdev_gendev);
+ up_write(&class->subsys.rwsem);
+ }
+
+ put_device(&sdev->sdev_gendev);
+
+ class_put(&sdev_class);
}
int scsi_register_driver(struct device_driver *drv)
diff -puN include/scsi/scsi_device.h~sdev_state include/scsi/scsi_device.h
--- patched-scsi-misc-2.5/include/scsi/scsi_device.h~sdev_state Fri Aug 1 07:07:20 2003
+++ patched-scsi-misc-2.5-andmike/include/scsi/scsi_device.h Fri Aug 1 07:07:20 2003
@@ -10,6 +10,16 @@ struct scsi_cmnd;
struct scsi_mode_data;
+/*
+ * sdev state
+ */
+enum {
+ SDEV_ADD,
+ SDEV_DEL,
+ SDEV_CANCEL,
+ SDEV_RECOVERY,
+};
+
struct scsi_device {
struct list_head siblings; /* list of all devices on this host */
struct list_head same_target_siblings; /* just the devices sharing same target id */
@@ -86,9 +96,13 @@ struct scsi_device {
struct device sdev_gendev;
struct class_device sdev_classdev;
+
+ unsigned long sdev_state;
};
#define to_scsi_device(d) \
container_of(d, struct scsi_device, sdev_gendev)
+#define class_to_sdev(d) \
+ container_of(d, struct scsi_device, sdev_classdev)
extern struct scsi_device *scsi_add_device(struct Scsi_Host *,
uint, uint, uint);
@@ -107,5 +121,4 @@ extern int scsi_set_medium_removal(struc
extern int scsi_mode_sense(struct scsi_device *sdev, int dbd, int modepage,
unsigned char *buffer, int len, int timeout,
int retries, struct scsi_mode_data *data);
-
#endif /* _SCSI_SCSI_DEVICE_H */
_
next prev parent reply other threads:[~2003-08-01 20:41 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2003-08-01 20:24 [PATCH] scsi host / scsi device ref counting take 2 [1/3] Mike Anderson
2003-08-01 20:25 ` [PATCH] scsi host / scsi device ref counting take 2 [2/3] Mike Anderson
2003-08-01 20:26 ` Mike Anderson [this message]
2003-08-02 16:50 ` [PATCH] scsi host / scsi device ref counting take 2 [1/3] Christoph Hellwig
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