1 files changed, 135 insertions, 81 deletions

diff --git a/drivers/s390/block/dasd_genhd.c b/drivers/s390/block/dasd_genhd.c
index f64921756ad6..6ee3d952412e 100644
--- a/drivers/s390/block/dasd_genhd.c
+++ b/drivers/s390/block/dasd_genhd.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * Author(s)......: Holger Smolinski <Holger.Smolinski@de.ibm.com>
  *		    Horst Hummel <Horst.Hummel@de.ibm.com>
@@ -10,87 +11,145 @@
  *
  */
 
-#define KMSG_COMPONENT "dasd"
-
 #include <linux/interrupt.h>
+#include <linux/major.h>
 #include <linux/fs.h>
 #include <linux/blkpg.h>
 
-#include <asm/uaccess.h>
-
-/* This is ugly... */
-#define PRINTK_HEADER "dasd_gendisk:"
+#include <linux/uaccess.h>
 
 #include "dasd_int.h"
 
+static unsigned int queue_depth = 32;
+static unsigned int nr_hw_queues = 4;
+static void dasd_gd_free(struct gendisk *gdp);
+
+module_param(queue_depth, uint, 0444);
+MODULE_PARM_DESC(queue_depth, "Default queue depth for new DASD devices");
+
+module_param(nr_hw_queues, uint, 0444);
+MODULE_PARM_DESC(nr_hw_queues, "Default number of hardware queues for new DASD devices");
+
+/*
+ * Set device name.
+ *   dasda - dasdz : 26 devices
+ *   dasdaa - dasdzz : 676 devices, added up = 702
+ *   dasdaaa - dasdzzz : 17576 devices, added up = 18278
+ *   dasdaaaa - dasdzzzz : 456976 devices, added up = 475252
+ */
+static int dasd_name_format(char *prefix, int index, char *buf, int buflen)
+{
+	const int base = 'z' - 'a' + 1;
+	char *begin = buf + strlen(prefix);
+	char *end = buf + buflen;
+	char *p;
+	int unit;
+
+	p = end - 1;
+	*p = '\0';
+	unit = base;
+	do {
+		if (p == begin)
+			return -EINVAL;
+		*--p = 'a' + (index % unit);
+		index = (index / unit) - 1;
+	} while (index >= 0);
+
+	memmove(begin, p, end - p);
+	memcpy(buf, prefix, strlen(prefix));
+
+	return 0;
+}
+
 /*
  * Allocate and register gendisk structure for device.
  */
 int dasd_gendisk_alloc(struct dasd_block *block)
 {
+	struct queue_limits lim = {
+		/*
+		 * With page sized segments, each segment can be translated into
+		 * one idaw/tidaw.
+		 */
+		.max_segment_size = PAGE_SIZE,
+		.seg_boundary_mask = PAGE_SIZE - 1,
+		.max_segments = USHRT_MAX,
+	};
 	struct gendisk *gdp;
 	struct dasd_device *base;
-	int len;
+	unsigned int devindex;
+	int rc;
 
 	/* Make sure the minor for this device exists. */
 	base = block->base;
-	if (base->devindex >= DASD_PER_MAJOR)
+	devindex = base->devindex;
+	if (devindex >= DASD_PER_MAJOR)
 		return -EBUSY;
 
-	gdp = alloc_disk(1 << DASD_PARTN_BITS);
-	if (!gdp)
-		return -ENOMEM;
+	block->tag_set.ops = &dasd_mq_ops;
+	block->tag_set.cmd_size = sizeof(struct dasd_ccw_req);
+	block->tag_set.nr_hw_queues = nr_hw_queues;
+	block->tag_set.queue_depth = queue_depth;
+	block->tag_set.numa_node = NUMA_NO_NODE;
+	rc = blk_mq_alloc_tag_set(&block->tag_set);
+	if (rc)
+		return rc;
+
+	gdp = blk_mq_alloc_disk(&block->tag_set, &lim, block);
+	if (IS_ERR(gdp)) {
+		blk_mq_free_tag_set(&block->tag_set);
+		return PTR_ERR(gdp);
+	}
 
 	/* Initialize gendisk structure. */
 	gdp->major = DASD_MAJOR;
-	gdp->first_minor = base->devindex << DASD_PARTN_BITS;
+	gdp->first_minor = devindex << DASD_PARTN_BITS;
+	gdp->minors = 1 << DASD_PARTN_BITS;
 	gdp->fops = &dasd_device_operations;
-	gdp->driverfs_dev = &base->cdev->dev;
 
-	/*
-	 * Set device name.
-	 *   dasda - dasdz : 26 devices
-	 *   dasdaa - dasdzz : 676 devices, added up = 702
-	 *   dasdaaa - dasdzzz : 17576 devices, added up = 18278
-	 *   dasdaaaa - dasdzzzz : 456976 devices, added up = 475252
-	 */
-	len = sprintf(gdp->disk_name, "dasd");
-	if (base->devindex > 25) {
-		if (base->devindex > 701) {
-			if (base->devindex > 18277)
-			        len += sprintf(gdp->disk_name + len, "%c",
-					       'a'+(((base->devindex-18278)
-						     /17576)%26));
-			len += sprintf(gdp->disk_name + len, "%c",
-				       'a'+(((base->devindex-702)/676)%26));
-		}
-		len += sprintf(gdp->disk_name + len, "%c",
-			       'a'+(((base->devindex-26)/26)%26));
+	rc = dasd_name_format("dasd", devindex, gdp->disk_name, sizeof(gdp->disk_name));
+	if (rc) {
+		DBF_DEV_EVENT(DBF_ERR, block->base,
+			      "setting disk name failed, rc %d", rc);
+		dasd_gd_free(gdp);
+		return rc;
 	}
-	len += sprintf(gdp->disk_name + len, "%c", 'a'+(base->devindex%26));
 
 	if (base->features & DASD_FEATURE_READONLY ||
 	    test_bit(DASD_FLAG_DEVICE_RO, &base->flags))
 		set_disk_ro(gdp, 1);
 	dasd_add_link_to_gendisk(gdp, base);
-	gdp->queue = block->request_queue;
 	block->gdp = gdp;
 	set_capacity(block->gdp, 0);
-	add_disk(block->gdp);
+
+	rc = device_add_disk(&base->cdev->dev, block->gdp, NULL);
+	if (rc) {
+		dasd_gendisk_free(block);
+		return rc;
+	}
+
 	return 0;
 }
 
 /*
+ * Free gendisk structure
+ */
+static void dasd_gd_free(struct gendisk *gd)
+{
+	del_gendisk(gd);
+	gd->private_data = NULL;
+	put_disk(gd);
+}
+
+/*
  * Unregister and free gendisk structure for device.
  */
 void dasd_gendisk_free(struct dasd_block *block)
 {
 	if (block->gdp) {
-		del_gendisk(block->gdp);
-		block->gdp->queue = NULL;
-		block->gdp->private_data = NULL;
-		put_disk(block->gdp);
+		dasd_gd_free(block->gdp);
 		block->gdp = NULL;
+		blk_mq_free_tag_set(&block->tag_set);
 	}
 }
 
@@ -99,27 +158,35 @@ void dasd_gendisk_free(struct dasd_block *block)
  */
 int dasd_scan_partitions(struct dasd_block *block)
 {
-	struct block_device *bdev;
+	struct file *bdev_file;
+	int rc;
 
-	bdev = bdget_disk(block->gdp, 0);
-	if (!bdev || blkdev_get(bdev, FMODE_READ, NULL) < 0)
+	bdev_file = bdev_file_open_by_dev(disk_devt(block->gdp), BLK_OPEN_READ,
+				       NULL, NULL);
+	if (IS_ERR(bdev_file)) {
+		DBF_DEV_EVENT(DBF_ERR, block->base,
+			      "scan partitions error, blkdev_get returned %ld",
+			      PTR_ERR(bdev_file));
 		return -ENODEV;
+	}
+
+	mutex_lock(&block->gdp->open_mutex);
+	rc = bdev_disk_changed(block->gdp, false);
+	mutex_unlock(&block->gdp->open_mutex);
+	if (rc)
+		DBF_DEV_EVENT(DBF_ERR, block->base,
+				"scan partitions error, rc %d", rc);
+
 	/*
-	 * See fs/partition/check.c:register_disk,rescan_partitions
-	 * Can't call rescan_partitions directly. Use ioctl.
-	 */
-	ioctl_by_bdev(bdev, BLKRRPART, 0);
-	/*
-	 * Since the matching blkdev_put call to the blkdev_get in
-	 * this function is not called before dasd_destroy_partitions
-	 * the offline open_count limit needs to be increased from
-	 * 0 to 1. This is done by setting device->bdev (see
-	 * dasd_generic_set_offline). As long as the partition
-	 * detection is running no offline should be allowed. That
-	 * is why the assignment to device->bdev is done AFTER
-	 * the BLKRRPART ioctl.
+	 * Since the matching fput() call to the
+	 * bdev_file_open_by_path() in this function is not called before
+	 * dasd_destroy_partitions the offline open_count limit needs to be
+	 * increased from 0 to 1. This is done by setting device->bdev_file
+	 * (see dasd_generic_set_offline). As long as the partition detection
+	 * is running no offline should be allowed. That is why the assignment
+	 * to block->bdev_file is done AFTER the BLKRRPART ioctl.
 	 */
-	block->bdev = bdev;
+	block->bdev_file = bdev_file;
 	return 0;
 }
 
@@ -129,34 +196,21 @@ int dasd_scan_partitions(struct dasd_block *block)
  */
 void dasd_destroy_partitions(struct dasd_block *block)
 {
-	/* The two structs have 168/176 byte on 31/64 bit. */
-	struct blkpg_partition bpart;
-	struct blkpg_ioctl_arg barg;
-	struct block_device *bdev;
+	struct file *bdev_file;
 
 	/*
-	 * Get the bdev pointer from the device structure and clear
-	 * device->bdev to lower the offline open_count limit again.
+	 * Get the bdev_file pointer from the device structure and clear
+	 * device->bdev_file to lower the offline open_count limit again.
 	 */
-	bdev = block->bdev;
-	block->bdev = NULL;
+	bdev_file = block->bdev_file;
+	block->bdev_file = NULL;
+
+	mutex_lock(&file_bdev(bdev_file)->bd_disk->open_mutex);
+	bdev_disk_changed(file_bdev(bdev_file)->bd_disk, true);
+	mutex_unlock(&file_bdev(bdev_file)->bd_disk->open_mutex);
 
-	/*
-	 * See fs/partition/check.c:delete_partition
-	 * Can't call delete_partitions directly. Use ioctl.
-	 * The ioctl also does locking and invalidation.
-	 */
-	memset(&bpart, 0, sizeof(struct blkpg_partition));
-	memset(&barg, 0, sizeof(struct blkpg_ioctl_arg));
-	barg.data = (void __force __user *) &bpart;
-	barg.op = BLKPG_DEL_PARTITION;
-	for (bpart.pno = block->gdp->minors - 1; bpart.pno > 0; bpart.pno--)
-		ioctl_by_bdev(bdev, BLKPG, (unsigned long) &barg);
-
-	invalidate_partition(block->gdp, 0);
 	/* Matching blkdev_put to the blkdev_get in dasd_scan_partitions. */
-	blkdev_put(bdev, FMODE_READ);
-	set_capacity(block->gdp, 0);
+	fput(bdev_file);
 }
 
 int dasd_gendisk_init(void)
@@ -166,8 +220,8 @@ int dasd_gendisk_init(void)
 	/* Register to static dasd major 94 */
 	rc = register_blkdev(DASD_MAJOR, "dasd");
 	if (rc != 0) {
-		pr_warning("Registering the device driver with major number "
-			   "%d failed\n", DASD_MAJOR);
+		pr_warn("Registering the device driver with major number %d failed\n",
+			DASD_MAJOR);
 		return rc;
 	}
 	return 0;