Merge patch series "scsi: Make use of bus callbacks"

Uwe Kleine-König <u.kleine-koenig@baylibre.com> says:

Hello,

this is v2 of the series to make the scsi subsystem stop using the
callbacks .probe(), .remove() and .shutdown() of struct device_driver.
Instead use their designated alternatives in struct bus_type.

The eventual goal is to drop the callbacks from struct device_driver.

The 2nd patch introduces some legacy handling for drivers still using
the device_driver callbacks. This results in a runtime warning (in
driver_register()). The following patches convert all in-tree drivers
(and thus fix the warnings one after another).
Conceptually this legacy handling could be dropped at the end of the
series, but I think this is a bad idea because this silently breaks
out-of-tree drivers (which also covers drivers that are currently
prepared for mainline submission) and in-tree drivers I might have
missed (though I'm convinced I catched them all). That convinces me that
keeping the legacy handling for at least one development cycle is the
right choice. I'll care for that at the latest when I remove the
callbacks from struct device_driver.

Link: https://patch.msgid.link/cover.1766133330.git.u.kleine-koenig@baylibre.com
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

8 files changed, 139 insertions, 72 deletions

diff --git a/drivers/scsi/ch.c b/drivers/scsi/ch.c
index fa07a6f54003..b6ca23a29ef5 100644
--- a/drivers/scsi/ch.c
+++ b/drivers/scsi/ch.c
@@ -894,9 +894,9 @@ static long ch_ioctl(struct file *file,
 
 /* ------------------------------------------------------------------------ */
 
-static int ch_probe(struct device *dev)
+static int ch_probe(struct scsi_device *sd)
 {
-	struct scsi_device *sd = to_scsi_device(dev);
+	struct device *dev = &sd->sdev_gendev;
 	struct device *class_dev;
 	int ret;
 	scsi_changer *ch;
@@ -967,8 +967,9 @@ free_ch:
 	return ret;
 }
 
-static int ch_remove(struct device *dev)
+static void ch_remove(struct scsi_device *sd)
 {
+	struct device *dev = &sd->sdev_gendev;
 	scsi_changer *ch = dev_get_drvdata(dev);
 
 	spin_lock(&ch_index_lock);
@@ -979,15 +980,14 @@ static int ch_remove(struct device *dev)
 	device_destroy(&ch_sysfs_class, MKDEV(SCSI_CHANGER_MAJOR, ch->minor));
 	scsi_device_put(ch->device);
 	kref_put(&ch->ref, ch_destroy);
-	return 0;
 }
 
 static struct scsi_driver ch_template = {
-	.gendrv     	= {
+	.probe = ch_probe,
+	.remove = ch_remove,
+	.gendrv = {
 		.name	= "ch",
 		.owner	= THIS_MODULE,
-		.probe  = ch_probe,
-		.remove = ch_remove,
 	},
 };
 
@@ -1014,7 +1014,7 @@ static int __init init_ch_module(void)
 		       SCSI_CHANGER_MAJOR);
 		goto fail1;
 	}
-	rc = scsi_register_driver(&ch_template.gendrv);
+	rc = scsi_register_driver(&ch_template);
 	if (rc < 0)
 		goto fail2;
 	return 0;
@@ -1028,7 +1028,7 @@ static int __init init_ch_module(void)
 
 static void __exit exit_ch_module(void)
 {
-	scsi_unregister_driver(&ch_template.gendrv);
+	scsi_unregister_driver(&ch_template);
 	unregister_chrdev(SCSI_CHANGER_MAJOR, "ch");
 	class_unregister(&ch_sysfs_class);
 	idr_destroy(&ch_index_idr);
diff --git a/drivers/scsi/scsi_sysfs.c b/drivers/scsi/scsi_sysfs.c
index 99eb0a30df61..6b8c5c05f294 100644
--- a/drivers/scsi/scsi_sysfs.c
+++ b/drivers/scsi/scsi_sysfs.c
@@ -554,10 +554,48 @@ static int scsi_bus_uevent(const struct device *dev, struct kobj_uevent_env *env
 	return 0;
 }
 
+static int scsi_bus_probe(struct device *dev)
+{
+	struct scsi_device *sdp = to_scsi_device(dev);
+	struct scsi_driver *drv = to_scsi_driver(dev->driver);
+
+	if (drv->probe)
+		return drv->probe(sdp);
+	else
+		return 0;
+}
+
+static void scsi_bus_remove(struct device *dev)
+{
+	struct scsi_device *sdp = to_scsi_device(dev);
+	struct scsi_driver *drv = to_scsi_driver(dev->driver);
+
+	if (drv->remove)
+		drv->remove(sdp);
+}
+
+static void scsi_bus_shutdown(struct device *dev)
+{
+	struct scsi_device *sdp = to_scsi_device(dev);
+	struct scsi_driver *drv;
+
+	if (!dev->driver)
+		return;
+
+	drv = to_scsi_driver(dev->driver);
+
+	if (drv->shutdown)
+		drv->shutdown(sdp);
+}
+
+
 const struct bus_type scsi_bus_type = {
-        .name		= "scsi",
-        .match		= scsi_bus_match,
+	.name		= "scsi",
+	.match		= scsi_bus_match,
 	.uevent		= scsi_bus_uevent,
+	.probe		= scsi_bus_probe,
+	.remove		= scsi_bus_remove,
+	.shutdown	= scsi_bus_shutdown,
 #ifdef CONFIG_PM
 	.pm		= &scsi_bus_pm_ops,
 #endif
@@ -1554,11 +1592,44 @@ restart:
 }
 EXPORT_SYMBOL(scsi_remove_target);
 
-int __scsi_register_driver(struct device_driver *drv, struct module *owner)
+static int scsi_legacy_probe(struct scsi_device *sdp)
+{
+	struct device *dev = &sdp->sdev_gendev;
+	struct device_driver *driver = dev->driver;
+
+	return driver->probe(dev);
+}
+
+static void scsi_legacy_remove(struct scsi_device *sdp)
+{
+	struct device *dev = &sdp->sdev_gendev;
+	struct device_driver *driver = dev->driver;
+
+	driver->remove(dev);
+}
+
+static void scsi_legacy_shutdown(struct scsi_device *sdp)
+{
+	struct device *dev = &sdp->sdev_gendev;
+	struct device_driver *driver = dev->driver;
+
+	driver->shutdown(dev);
+}
+
+int __scsi_register_driver(struct scsi_driver *sdrv, struct module *owner)
 {
+	struct device_driver *drv = &sdrv->gendrv;
+
 	drv->bus = &scsi_bus_type;
 	drv->owner = owner;
 
+	if (!sdrv->probe && drv->probe)
+		sdrv->probe = scsi_legacy_probe;
+	if (!sdrv->remove && drv->remove)
+		sdrv->remove = scsi_legacy_remove;
+	if (!sdrv->shutdown && drv->shutdown)
+		sdrv->shutdown = scsi_legacy_shutdown;
+
 	return driver_register(drv);
 }
 EXPORT_SYMBOL(__scsi_register_driver);
diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c
index f50b92e63201..dc7eac6211bc 100644
--- a/drivers/scsi/sd.c
+++ b/drivers/scsi/sd.c
@@ -108,7 +108,7 @@ static void sd_config_write_same(struct scsi_disk *sdkp,
 		struct queue_limits *lim);
 static void  sd_revalidate_disk(struct gendisk *);
 static void sd_unlock_native_capacity(struct gendisk *disk);
-static void sd_shutdown(struct device *);
+static void sd_shutdown(struct scsi_device *);
 static void scsi_disk_release(struct device *cdev);
 
 static DEFINE_IDA(sd_index_ida);
@@ -3935,7 +3935,7 @@ static int sd_format_disk_name(char *prefix, int index, char *buf, int buflen)
  *	sd_probe - called during driver initialization and whenever a
  *	new scsi device is attached to the system. It is called once
  *	for each scsi device (not just disks) present.
- *	@dev: pointer to device object
+ *	@sdp: pointer to device object
  *
  *	Returns 0 if successful (or not interested in this scsi device 
  *	(e.g. scanner)); 1 when there is an error.
@@ -3949,9 +3949,9 @@ static int sd_format_disk_name(char *prefix, int index, char *buf, int buflen)
  *	Assume sd_probe is not re-entrant (for time being)
  *	Also think about sd_probe() and sd_remove() running coincidentally.
  **/
-static int sd_probe(struct device *dev)
+static int sd_probe(struct scsi_device *sdp)
 {
-	struct scsi_device *sdp = to_scsi_device(dev);
+	struct device *dev = &sdp->sdev_gendev;
 	struct scsi_disk *sdkp;
 	struct gendisk *gd;
 	int index;
@@ -4091,15 +4091,16 @@ static int sd_probe(struct device *dev)
  *	sd_remove - called whenever a scsi disk (previously recognized by
  *	sd_probe) is detached from the system. It is called (potentially
  *	multiple times) during sd module unload.
- *	@dev: pointer to device object
+ *	@sdp: pointer to device object
  *
  *	Note: this function is invoked from the scsi mid-level.
  *	This function potentially frees up a device name (e.g. /dev/sdc)
  *	that could be re-used by a subsequent sd_probe().
  *	This function is not called when the built-in sd driver is "exit-ed".
  **/
-static int sd_remove(struct device *dev)
+static void sd_remove(struct scsi_device *sdp)
 {
+	struct device *dev = &sdp->sdev_gendev;
 	struct scsi_disk *sdkp = dev_get_drvdata(dev);
 
 	scsi_autopm_get_device(sdkp->device);
@@ -4107,10 +4108,9 @@ static int sd_remove(struct device *dev)
 	device_del(&sdkp->disk_dev);
 	del_gendisk(sdkp->disk);
 	if (!sdkp->suspended)
-		sd_shutdown(dev);
+		sd_shutdown(sdp);
 
 	put_disk(sdkp->disk);
-	return 0;
 }
 
 static void scsi_disk_release(struct device *dev)
@@ -4197,8 +4197,9 @@ static int sd_start_stop_device(struct scsi_disk *sdkp, int start)
  * the normal SCSI command structure.  Wait for the command to
  * complete.
  */
-static void sd_shutdown(struct device *dev)
+static void sd_shutdown(struct scsi_device *sdp)
 {
+	struct device *dev = &sdp->sdev_gendev;
 	struct scsi_disk *sdkp = dev_get_drvdata(dev);
 
 	if (!sdkp)
@@ -4368,12 +4369,12 @@ static const struct dev_pm_ops sd_pm_ops = {
 };
 
 static struct scsi_driver sd_template = {
+	.probe = sd_probe,
+	.remove = sd_remove,
+	.shutdown = sd_shutdown,
 	.gendrv = {
 		.name		= "sd",
-		.probe		= sd_probe,
 		.probe_type	= PROBE_PREFER_ASYNCHRONOUS,
-		.remove		= sd_remove,
-		.shutdown	= sd_shutdown,
 		.pm		= &sd_pm_ops,
 	},
 	.rescan			= sd_rescan,
@@ -4417,7 +4418,7 @@ static int __init init_sd(void)
 		goto err_out_class;
 	}
 
-	err = scsi_register_driver(&sd_template.gendrv);
+	err = scsi_register_driver(&sd_template);
 	if (err)
 		goto err_out_driver;
 
@@ -4444,7 +4445,7 @@ static void __exit exit_sd(void)
 
 	SCSI_LOG_HLQUEUE(3, printk("exit_sd: exiting sd driver\n"));
 
-	scsi_unregister_driver(&sd_template.gendrv);
+	scsi_unregister_driver(&sd_template);
 	mempool_destroy(sd_page_pool);
 
 	class_unregister(&sd_disk_class);
diff --git a/drivers/scsi/ses.c b/drivers/scsi/ses.c
index 2c61624cb4b0..789b170da652 100644
--- a/drivers/scsi/ses.c
+++ b/drivers/scsi/ses.c
@@ -42,9 +42,8 @@ static bool ses_page2_supported(struct enclosure_device *edev)
 	return (ses_dev->page2 != NULL);
 }
 
-static int ses_probe(struct device *dev)
+static int ses_probe(struct scsi_device *sdev)
 {
-	struct scsi_device *sdev = to_scsi_device(dev);
 	int err = -ENODEV;
 
 	if (sdev->type != TYPE_ENCLOSURE)
@@ -847,11 +846,6 @@ page2_not_supported:
 	return err;
 }
 
-static int ses_remove(struct device *dev)
-{
-	return 0;
-}
-
 static void ses_intf_remove_component(struct scsi_device *sdev)
 {
 	struct enclosure_device *edev, *prev = NULL;
@@ -906,10 +900,9 @@ static struct class_interface ses_interface = {
 };
 
 static struct scsi_driver ses_template = {
+	.probe = ses_probe,
 	.gendrv = {
 		.name		= "ses",
-		.probe		= ses_probe,
-		.remove		= ses_remove,
 	},
 };
 
@@ -921,7 +914,7 @@ static int __init ses_init(void)
 	if (err)
 		return err;
 
-	err = scsi_register_driver(&ses_template.gendrv);
+	err = scsi_register_driver(&ses_template);
 	if (err)
 		goto out_unreg;
 
@@ -934,7 +927,7 @@ static int __init ses_init(void)
 
 static void __exit ses_exit(void)
 {
-	scsi_unregister_driver(&ses_template.gendrv);
+	scsi_unregister_driver(&ses_template);
 	scsi_unregister_interface(&ses_interface);
 }
 
diff --git a/drivers/scsi/sr.c b/drivers/scsi/sr.c
index add13e306898..1fb85f548955 100644
--- a/drivers/scsi/sr.c
+++ b/drivers/scsi/sr.c
@@ -82,8 +82,8 @@ MODULE_ALIAS_SCSI_DEVICE(TYPE_WORM);
 	 CDC_CD_R|CDC_CD_RW|CDC_DVD|CDC_DVD_R|CDC_DVD_RAM|CDC_GENERIC_PACKET| \
 	 CDC_MRW|CDC_MRW_W|CDC_RAM)
 
-static int sr_probe(struct device *);
-static int sr_remove(struct device *);
+static int sr_probe(struct scsi_device *);
+static void sr_remove(struct scsi_device *);
 static blk_status_t sr_init_command(struct scsi_cmnd *SCpnt);
 static int sr_done(struct scsi_cmnd *);
 static int sr_runtime_suspend(struct device *dev);
@@ -93,10 +93,10 @@ static const struct dev_pm_ops sr_pm_ops = {
 };
 
 static struct scsi_driver sr_template = {
+	.probe = sr_probe,
+	.remove = sr_remove,
 	.gendrv = {
 		.name   	= "sr",
-		.probe		= sr_probe,
-		.remove		= sr_remove,
 		.pm		= &sr_pm_ops,
 	},
 	.init_command		= sr_init_command,
@@ -616,9 +616,9 @@ static void sr_release(struct cdrom_device_info *cdi)
 {
 }
 
-static int sr_probe(struct device *dev)
+static int sr_probe(struct scsi_device *sdev)
 {
-	struct scsi_device *sdev = to_scsi_device(dev);
+	struct device *dev = &sdev->sdev_gendev;
 	struct gendisk *disk;
 	struct scsi_cd *cd;
 	int minor, error;
@@ -982,16 +982,15 @@ out_put_request:
 	return ret;
 }
 
-static int sr_remove(struct device *dev)
+static void sr_remove(struct scsi_device *sdev)
 {
+	struct device *dev = &sdev->sdev_gendev;
 	struct scsi_cd *cd = dev_get_drvdata(dev);
 
 	scsi_autopm_get_device(cd->device);
 
 	del_gendisk(cd->disk);
 	put_disk(cd->disk);
-
-	return 0;
 }
 
 static int __init init_sr(void)
@@ -1001,7 +1000,7 @@ static int __init init_sr(void)
 	rc = register_blkdev(SCSI_CDROM_MAJOR, "sr");
 	if (rc)
 		return rc;
-	rc = scsi_register_driver(&sr_template.gendrv);
+	rc = scsi_register_driver(&sr_template);
 	if (rc)
 		unregister_blkdev(SCSI_CDROM_MAJOR, "sr");
 
@@ -1010,7 +1009,7 @@ static int __init init_sr(void)
 
 static void __exit exit_sr(void)
 {
-	scsi_unregister_driver(&sr_template.gendrv);
+	scsi_unregister_driver(&sr_template);
 	unregister_blkdev(SCSI_CDROM_MAJOR, "sr");
 }
 
diff --git a/drivers/scsi/st.c b/drivers/scsi/st.c
index 168f25e4aaa3..40d88bbb4388 100644
--- a/drivers/scsi/st.c
+++ b/drivers/scsi/st.c
@@ -202,14 +202,14 @@ static int sgl_map_user_pages(struct st_buffer *, const unsigned int,
 			      unsigned long, size_t, int);
 static int sgl_unmap_user_pages(struct st_buffer *, const unsigned int, int);
 
-static int st_probe(struct device *);
-static int st_remove(struct device *);
+static int st_probe(struct scsi_device *);
+static void st_remove(struct scsi_device *);
 
 static struct scsi_driver st_template = {
+	.probe = st_probe,
+	.remove = st_remove,
 	.gendrv = {
 		.name		= "st",
-		.probe		= st_probe,
-		.remove		= st_remove,
 		.groups		= st_drv_groups,
 	},
 };
@@ -4342,9 +4342,9 @@ static void remove_cdevs(struct scsi_tape *tape)
 	}
 }
 
-static int st_probe(struct device *dev)
+static int st_probe(struct scsi_device *SDp)
 {
-	struct scsi_device *SDp = to_scsi_device(dev);
+	struct device *dev = &SDp->sdev_gendev;
 	struct scsi_tape *tpnt = NULL;
 	struct st_modedef *STm;
 	struct st_partstat *STps;
@@ -4499,12 +4499,13 @@ out:
 };
 
 
-static int st_remove(struct device *dev)
+static void st_remove(struct scsi_device *SDp)
 {
+	struct device *dev = &SDp->sdev_gendev;
 	struct scsi_tape *tpnt = dev_get_drvdata(dev);
 	int index = tpnt->index;
 
-	scsi_autopm_get_device(to_scsi_device(dev));
+	scsi_autopm_get_device(SDp);
 	remove_cdevs(tpnt);
 
 	mutex_lock(&st_ref_mutex);
@@ -4513,7 +4514,6 @@ static int st_remove(struct device *dev)
 	spin_lock(&st_index_lock);
 	idr_remove(&st_index_idr, index);
 	spin_unlock(&st_index_lock);
-	return 0;
 }
 
 /**
@@ -4576,7 +4576,7 @@ static int __init init_st(void)
 		goto err_class;
 	}
 
-	err = scsi_register_driver(&st_template.gendrv);
+	err = scsi_register_driver(&st_template);
 	if (err)
 		goto err_chrdev;
 
@@ -4592,7 +4592,7 @@ err_class:
 
 static void __exit exit_st(void)
 {
-	scsi_unregister_driver(&st_template.gendrv);
+	scsi_unregister_driver(&st_template);
 	unregister_chrdev_region(MKDEV(SCSI_TAPE_MAJOR, 0),
 				 ST_MAX_TAPE_ENTRIES);
 	class_unregister(&st_sysfs_class);
diff --git a/drivers/ufs/core/ufshcd.c b/drivers/ufs/core/ufshcd.c
index 80c0b49f30b0..78669c205568 100644
--- a/drivers/ufs/core/ufshcd.c
+++ b/drivers/ufs/core/ufshcd.c
@@ -10525,9 +10525,8 @@ int ufshcd_runtime_resume(struct device *dev)
 EXPORT_SYMBOL(ufshcd_runtime_resume);
 #endif /* CONFIG_PM */
 
-static void ufshcd_wl_shutdown(struct device *dev)
+static void ufshcd_wl_shutdown(struct scsi_device *sdev)
 {
-	struct scsi_device *sdev = to_scsi_device(dev);
 	struct ufs_hba *hba = shost_priv(sdev->host);
 
 	down(&hba->host_sem);
@@ -11133,9 +11132,9 @@ static int ufshcd_wl_poweroff(struct device *dev)
 }
 #endif
 
-static int ufshcd_wl_probe(struct device *dev)
+static int ufshcd_wl_probe(struct scsi_device *sdev)
 {
-	struct scsi_device *sdev = to_scsi_device(dev);
+	struct device *dev = &sdev->sdev_gendev;
 
 	if (!is_device_wlun(sdev))
 		return -ENODEV;
@@ -11147,10 +11146,11 @@ static int ufshcd_wl_probe(struct device *dev)
 	return  0;
 }
 
-static int ufshcd_wl_remove(struct device *dev)
+static void ufshcd_wl_remove(struct scsi_device *sdev)
 {
+	struct device *dev = &sdev->sdev_gendev;
+
 	pm_runtime_forbid(dev);
-	return 0;
 }
 
 static const struct dev_pm_ops ufshcd_wl_pm_ops = {
@@ -11223,12 +11223,12 @@ static void ufshcd_check_header_layout(void)
  * Hence register a scsi driver for ufs wluns only.
  */
 static struct scsi_driver ufs_dev_wlun_template = {
+	.probe = ufshcd_wl_probe,
+	.remove = ufshcd_wl_remove,
+	.shutdown = ufshcd_wl_shutdown,
 	.gendrv = {
 		.name = "ufs_device_wlun",
-		.probe = ufshcd_wl_probe,
-		.remove = ufshcd_wl_remove,
 		.pm = &ufshcd_wl_pm_ops,
-		.shutdown = ufshcd_wl_shutdown,
 	},
 };
 
@@ -11240,7 +11240,7 @@ static int __init ufshcd_core_init(void)
 
 	ufs_debugfs_init();
 
-	ret = scsi_register_driver(&ufs_dev_wlun_template.gendrv);
+	ret = scsi_register_driver(&ufs_dev_wlun_template);
 	if (ret)
 		ufs_debugfs_exit();
 	return ret;
@@ -11249,7 +11249,7 @@ static int __init ufshcd_core_init(void)
 static void __exit ufshcd_core_exit(void)
 {
 	ufs_debugfs_exit();
-	scsi_unregister_driver(&ufs_dev_wlun_template.gendrv);
+	scsi_unregister_driver(&ufs_dev_wlun_template);
 }
 
 module_init(ufshcd_core_init);
diff --git a/include/scsi/scsi_driver.h b/include/scsi/scsi_driver.h
index c0e89996bdb3..249cea724abd 100644
--- a/include/scsi/scsi_driver.h
+++ b/include/scsi/scsi_driver.h
@@ -12,6 +12,9 @@ struct request;
 struct scsi_driver {
 	struct device_driver	gendrv;
 
+	int (*probe)(struct scsi_device *);
+	void (*remove)(struct scsi_device *);
+	void (*shutdown)(struct scsi_device *);
 	int (*resume)(struct device *);
 	void (*rescan)(struct device *);
 	blk_status_t (*init_command)(struct scsi_cmnd *);
@@ -25,9 +28,9 @@ struct scsi_driver {
 
 #define scsi_register_driver(drv) \
 	__scsi_register_driver(drv, THIS_MODULE)
-int __scsi_register_driver(struct device_driver *, struct module *);
+int __scsi_register_driver(struct scsi_driver *, struct module *);
 #define scsi_unregister_driver(drv) \
-	driver_unregister(drv);
+	driver_unregister(&(drv)->gendrv);
 
 extern int scsi_register_interface(struct class_interface *);
 #define scsi_unregister_interface(intf) \