From 27ba3e8ff3ab86449e63d38a8d623053591e65fa Mon Sep 17 00:00:00 2001 From: Damien Le Moal Date: Tue, 15 Sep 2020 16:33:46 +0900 Subject: [PATCH] scsi: sd: sd_zbc: Fix handling of host-aware ZBC disks When CONFIG_BLK_DEV_ZONED is disabled, allow using host-aware ZBC disks as regular disks. In this case, ensure that command completion is correctly executed by changing sd_zbc_complete() to return good_bytes instead of 0 and causing a hang during device probe (endless retries). When CONFIG_BLK_DEV_ZONED is enabled and a host-aware disk is detected to have partitions, it will be used as a regular disk. In this case, make sure to not do anything in sd_zbc_revalidate_zones() as that triggers warnings. Since all these different cases result in subtle settings of the disk queue zoned model, introduce the block layer helper function blk_queue_set_zoned() to generically implement setting up the effective zoned model according to the disk type, the presence of partitions on the disk and CONFIG_BLK_DEV_ZONED configuration. Link: https://lore.kernel.org/r/20200915073347.832424-2-damien.lemoal@wdc.com Fixes: b72053072c0b ("block: allow partitions on host aware zone devices") Cc: Reported-by: Borislav Petkov Suggested-by: Christoph Hellwig Reviewed-by: Christoph Hellwig Reviewed-by: Johannes Thumshirn Signed-off-by: Damien Le Moal Signed-off-by: Martin K. Petersen --- block/blk-settings.c | 46 ++++++++++++++++++++++++++++++++++++++++++++++ drivers/scsi/sd.c | 30 ++++++++++++++++++------------ drivers/scsi/sd.h | 2 +- drivers/scsi/sd_zbc.c | 6 +++++- include/linux/blkdev.h | 2 ++ 5 files changed, 72 insertions(+), 14 deletions(-) diff --git a/block/blk-settings.c b/block/blk-settings.c index 76a7e03..34b721a 100644 --- a/block/blk-settings.c +++ b/block/blk-settings.c @@ -801,6 +801,52 @@ bool blk_queue_can_use_dma_map_merging(struct request_queue *q, } EXPORT_SYMBOL_GPL(blk_queue_can_use_dma_map_merging); +/** + * blk_queue_set_zoned - configure a disk queue zoned model. + * @disk: the gendisk of the queue to configure + * @model: the zoned model to set + * + * Set the zoned model of the request queue of @disk according to @model. + * When @model is BLK_ZONED_HM (host managed), this should be called only + * if zoned block device support is enabled (CONFIG_BLK_DEV_ZONED option). + * If @model specifies BLK_ZONED_HA (host aware), the effective model used + * depends on CONFIG_BLK_DEV_ZONED settings and on the existence of partitions + * on the disk. + */ +void blk_queue_set_zoned(struct gendisk *disk, enum blk_zoned_model model) +{ + switch (model) { + case BLK_ZONED_HM: + /* + * Host managed devices are supported only if + * CONFIG_BLK_DEV_ZONED is enabled. + */ + WARN_ON_ONCE(!IS_ENABLED(CONFIG_BLK_DEV_ZONED)); + break; + case BLK_ZONED_HA: + /* + * Host aware devices can be treated either as regular block + * devices (similar to drive managed devices) or as zoned block + * devices to take advantage of the zone command set, similarly + * to host managed devices. We try the latter if there are no + * partitions and zoned block device support is enabled, else + * we do nothing special as far as the block layer is concerned. + */ + if (!IS_ENABLED(CONFIG_BLK_DEV_ZONED) || + disk_has_partitions(disk)) + model = BLK_ZONED_NONE; + break; + case BLK_ZONED_NONE: + default: + if (WARN_ON_ONCE(model != BLK_ZONED_NONE)) + model = BLK_ZONED_NONE; + break; + } + + disk->queue->limits.zoned = model; +} +EXPORT_SYMBOL_GPL(blk_queue_set_zoned); + static int __init blk_settings_init(void) { blk_max_low_pfn = max_low_pfn - 1; diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c index 95018e6..06286b6 100644 --- a/drivers/scsi/sd.c +++ b/drivers/scsi/sd.c @@ -2964,26 +2964,32 @@ static void sd_read_block_characteristics(struct scsi_disk *sdkp) if (sdkp->device->type == TYPE_ZBC) { /* Host-managed */ - q->limits.zoned = BLK_ZONED_HM; + blk_queue_set_zoned(sdkp->disk, BLK_ZONED_HM); } else { sdkp->zoned = (buffer[8] >> 4) & 3; - if (sdkp->zoned == 1 && !disk_has_partitions(sdkp->disk)) { + if (sdkp->zoned == 1) { /* Host-aware */ - q->limits.zoned = BLK_ZONED_HA; + blk_queue_set_zoned(sdkp->disk, BLK_ZONED_HA); } else { - /* - * Treat drive-managed devices and host-aware devices - * with partitions as regular block devices. - */ - q->limits.zoned = BLK_ZONED_NONE; - if (sdkp->zoned == 2 && sdkp->first_scan) - sd_printk(KERN_NOTICE, sdkp, - "Drive-managed SMR disk\n"); + /* Regular disk or drive managed disk */ + blk_queue_set_zoned(sdkp->disk, BLK_ZONED_NONE); } } - if (blk_queue_is_zoned(q) && sdkp->first_scan) + + if (!sdkp->first_scan) + goto out; + + if (blk_queue_is_zoned(q)) { sd_printk(KERN_NOTICE, sdkp, "Host-%s zoned block device\n", q->limits.zoned == BLK_ZONED_HM ? "managed" : "aware"); + } else { + if (sdkp->zoned == 1) + sd_printk(KERN_NOTICE, sdkp, + "Host-aware SMR disk used as regular disk\n"); + else if (sdkp->zoned == 2) + sd_printk(KERN_NOTICE, sdkp, + "Drive-managed SMR disk\n"); + } out: kfree(buffer); diff --git a/drivers/scsi/sd.h b/drivers/scsi/sd.h index 4933e7d..7251434 100644 --- a/drivers/scsi/sd.h +++ b/drivers/scsi/sd.h @@ -259,7 +259,7 @@ static inline blk_status_t sd_zbc_setup_zone_mgmt_cmnd(struct scsi_cmnd *cmd, static inline unsigned int sd_zbc_complete(struct scsi_cmnd *cmd, unsigned int good_bytes, struct scsi_sense_hdr *sshdr) { - return 0; + return good_bytes; } static inline blk_status_t sd_zbc_prepare_zone_append(struct scsi_cmnd *cmd, diff --git a/drivers/scsi/sd_zbc.c b/drivers/scsi/sd_zbc.c index 0e94ff0..a739456 100644 --- a/drivers/scsi/sd_zbc.c +++ b/drivers/scsi/sd_zbc.c @@ -667,7 +667,11 @@ int sd_zbc_revalidate_zones(struct scsi_disk *sdkp) u32 max_append; int ret = 0; - if (!sd_is_zoned(sdkp)) + /* + * There is nothing to do for regular disks, including host-aware disks + * that have partitions. + */ + if (!blk_queue_is_zoned(q)) return 0; /* diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index bb5636c..868e11f 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -352,6 +352,8 @@ struct queue_limits { typedef int (*report_zones_cb)(struct blk_zone *zone, unsigned int idx, void *data); +void blk_queue_set_zoned(struct gendisk *disk, enum blk_zoned_model model); + #ifdef CONFIG_BLK_DEV_ZONED #define BLK_ALL_ZONES ((unsigned int)-1) -- 2.7.4