Commit 45938335 authored by Christoph Hellwig's avatar Christoph Hellwig Committed by Jens Axboe
Browse files

st: do not allocate a gendisk 



st is a character driver and thus does not need to allocate a gendisk,
which is only used for file system-like block layer I/O on block
devices.

Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20210816131910.615153-3-hch@lst.de


Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent 5f432cce

drivers/scsi/st.c

+12 −37
Original line number Diff line number Diff line
@@ -309,13 +309,8 @@ static char * st_incompatible(struct scsi_device* SDp) 
}





static inline char *tape_name(struct scsi_tape *tape)

{

	return tape->disk->disk_name;

}



#define st_printk(prefix, t, fmt, a...) \

	sdev_prefix_printk(prefix, (t)->device, tape_name(t), fmt, ##a)

	sdev_prefix_printk(prefix, (t)->device, (t)->name, fmt, ##a)

#ifdef DEBUG

#define DEBC_printk(t, fmt, a...) \

	if (debugging) { st_printk(ST_DEB_MSG, t, fmt, ##a ); }
@@ -363,7 +358,7 @@ static int st_chk_result(struct scsi_tape *STp, struct st_request * SRpnt) 
	int result = SRpnt->result;

	u8 scode;

	DEB(const char *stp;)

	char *name = tape_name(STp);

	char *name = STp->name;

	struct st_cmdstatus *cmdstatp;



	if (!result)
@@ -3841,8 +3836,9 @@ static long st_ioctl_common(struct file *file, unsigned int cmd_in, void __user 
			    !capable(CAP_SYS_RAWIO))

				i = -EPERM;

			else

				i = scsi_cmd_ioctl(STp->disk->queue, STp->disk,

						   file->f_mode, cmd_in, p);

				i = scsi_cmd_ioctl(STp->device->request_queue,

						   NULL, file->f_mode, cmd_in,

						   p);

			if (i != -ENOTTY)

				return i;

			break;
@@ -4216,7 +4212,7 @@ static int create_one_cdev(struct scsi_tape *tape, int mode, int rew) 


	i = mode << (4 - ST_NBR_MODE_BITS);

	snprintf(name, 10, "%s%s%s", rew ? "n" : "",

		 tape->disk->disk_name, st_formats[i]);

		 tape->name, st_formats[i]);



	dev = device_create(&st_sysfs_class, &tape->device->sdev_gendev,

			    cdev_devno, &tape->modes[mode], "%s", name);
@@ -4271,7 +4267,6 @@ static void remove_cdevs(struct scsi_tape *tape) 
static int st_probe(struct device *dev)

{

	struct scsi_device *SDp = to_scsi_device(dev);

	struct gendisk *disk = NULL;

	struct scsi_tape *tpnt = NULL;

	struct st_modedef *STm;

	struct st_partstat *STps;
@@ -4301,27 +4296,13 @@ static int st_probe(struct device *dev) 
		goto out;

	}



	disk = alloc_disk(1);

	if (!disk) {

		sdev_printk(KERN_ERR, SDp,

			    "st: out of memory. Device not attached.\n");

		goto out_buffer_free;

	}



	tpnt = kzalloc(sizeof(struct scsi_tape), GFP_KERNEL);

	if (tpnt == NULL) {

		sdev_printk(KERN_ERR, SDp,

			    "st: Can't allocate device descriptor.\n");

		goto out_put_disk;

		goto out_buffer_free;

	}

	kref_init(&tpnt->kref);

	tpnt->disk = disk;

	disk->private_data = &tpnt->driver;

	/* SCSI tape doesn't register this gendisk via add_disk().  Manually

	 * take queue reference that release_disk() expects. */

	if (!blk_get_queue(SDp->request_queue))

		goto out_put_disk;

	disk->queue = SDp->request_queue;

	tpnt->driver = &st_template;



	tpnt->device = SDp;
@@ -4394,10 +4375,10 @@ static int st_probe(struct device *dev) 
	idr_preload_end();

	if (error < 0) {

		pr_warn("st: idr allocation failed: %d\n", error);

		goto out_put_queue;

		goto out_free_tape;

	}

	tpnt->index = error;

	sprintf(disk->disk_name, "st%d", tpnt->index);

	sprintf(tpnt->name, "st%d", tpnt->index);

	tpnt->stats = kzalloc(sizeof(struct scsi_tape_stats), GFP_KERNEL);

	if (tpnt->stats == NULL) {

		sdev_printk(KERN_ERR, SDp,
@@ -4414,9 +4395,9 @@ static int st_probe(struct device *dev) 
	scsi_autopm_put_device(SDp);



	sdev_printk(KERN_NOTICE, SDp,

		    "Attached scsi tape %s\n", tape_name(tpnt));

		    "Attached scsi tape %s\n", tpnt->name);

	sdev_printk(KERN_INFO, SDp, "%s: try direct i/o: %s (alignment %d B)\n",

		    tape_name(tpnt), tpnt->try_dio ? "yes" : "no",

		    tpnt->name, tpnt->try_dio ? "yes" : "no",

		    queue_dma_alignment(SDp->request_queue) + 1);



	return 0;
@@ -4428,10 +4409,7 @@ static int st_probe(struct device *dev) 
	spin_lock(&st_index_lock);

	idr_remove(&st_index_idr, tpnt->index);

	spin_unlock(&st_index_lock);

out_put_queue:

	blk_put_queue(disk->queue);

out_put_disk:

	put_disk(disk);

out_free_tape:

	kfree(tpnt);

out_buffer_free:

	kfree(buffer);
@@ -4470,7 +4448,6 @@ static int st_remove(struct device *dev) 
static void scsi_tape_release(struct kref *kref)

{

	struct scsi_tape *tpnt = to_scsi_tape(kref);

	struct gendisk *disk = tpnt->disk;



	tpnt->device = NULL;
@@ -4480,8 +4457,6 @@ static void scsi_tape_release(struct kref *kref) 
		kfree(tpnt->buffer);

	}



	disk->private_data = NULL;

	put_disk(disk);

	kfree(tpnt->stats);

	kfree(tpnt);

	return;

drivers/scsi/st.h

+1 −1
Original line number Diff line number Diff line
@@ -187,7 +187,7 @@ struct scsi_tape { 
	unsigned char last_cmnd[6];

	unsigned char last_sense[16];

#endif

	struct gendisk *disk;

	char name[DISK_NAME_LEN];

	struct kref     kref;

	struct scsi_tape_stats *stats;

};