sd: convert to the atomic queue limits API

Assign all queue limits through a local queue_limits variable and
queue_limits_commit_update so that we can't race updating them from
multiple places, and freeze the queue when updating them so that
in-progress I/O submissions don't see half-updated limits.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: John Garry <john.g.garry@oracle.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20240531074837.1648501-12-hch@lst.deSigned-off-by: Jens Axboe <axboe@kernel.dk>

drivers/scsi/sd.h

@@ -239,7 +239,8 @@ static inline int sd_is_zoned(struct scsi_disk *sdkp)
 
 #ifdef CONFIG_BLK_DEV_ZONED
 
-int sd_zbc_read_zones(struct scsi_disk *sdkp, u8 buf[SD_BUF_SIZE]);
+int sd_zbc_read_zones(struct scsi_disk *sdkp, struct queue_limits *lim,
+		u8 buf[SD_BUF_SIZE]);
 int sd_zbc_revalidate_zones(struct scsi_disk *sdkp);
 blk_status_t sd_zbc_setup_zone_mgmt_cmnd(struct scsi_cmnd *cmd,
 					 unsigned char op, bool all);
@@ -250,7 +251,8 @@ int sd_zbc_report_zones(struct gendisk *disk, sector_t sector,
 
 #else /* CONFIG_BLK_DEV_ZONED */
 
-static inline int sd_zbc_read_zones(struct scsi_disk *sdkp, u8 buf[SD_BUF_SIZE])
+static inline int sd_zbc_read_zones(struct scsi_disk *sdkp,
+		struct queue_limits *lim, u8 buf[SD_BUF_SIZE])
 {
 	return 0;
 }

drivers/scsi/sd_zbc.c

@@ -582,13 +582,15 @@ int sd_zbc_revalidate_zones(struct scsi_disk *sdkp)
 /**
  * sd_zbc_read_zones - Read zone information and update the request queue
  * @sdkp: SCSI disk pointer.
+ * @lim: queue limits to read into
  * @buf: 512 byte buffer used for storing SCSI command output.
  *
  * Read zone information and update the request queue zone characteristics and
  * also the zoned device information in *sdkp. Called by sd_revalidate_disk()
  * before the gendisk capacity has been set.
  */
-int sd_zbc_read_zones(struct scsi_disk *sdkp, u8 buf[SD_BUF_SIZE])
+int sd_zbc_read_zones(struct scsi_disk *sdkp, struct queue_limits *lim,
+		u8 buf[SD_BUF_SIZE])
 {
 	struct gendisk *disk = sdkp->disk;
 	struct request_queue *q = disk->queue;
@@ -626,14 +628,13 @@ int sd_zbc_read_zones(struct scsi_disk *sdkp, u8 buf[SD_BUF_SIZE])
 	/* The drive satisfies the kernel restrictions: set it up */
 	blk_queue_flag_set(QUEUE_FLAG_ZONE_RESETALL, q);
 	if (sdkp->zones_max_open == U32_MAX)
-		disk_set_max_open_zones(disk, 0);
+		lim->max_open_zones = 0;
 	else
-		disk_set_max_open_zones(disk, sdkp->zones_max_open);
-	disk_set_max_active_zones(disk, 0);
-	blk_queue_chunk_sectors(q,
-			logical_to_sectors(sdkp->device, zone_blocks));
+		lim->max_open_zones = sdkp->zones_max_open;
+	lim->max_active_zones = 0;
+	lim->chunk_sectors = logical_to_sectors(sdkp->device, zone_blocks);
 	/* Enable block layer zone append emulation */
-	blk_queue_max_zone_append_sectors(q, 0);
+	lim->max_zone_append_sectors = 0;
 
 	return 0;