summaryrefslogtreecommitdiffstats
path: root/block/blk-zoned.c
diff options
context:
space:
mode:
Diffstat (limited to 'block/blk-zoned.c')
-rw-r--r--block/blk-zoned.c565
1 files changed, 565 insertions, 0 deletions
diff --git a/block/blk-zoned.c b/block/blk-zoned.c
new file mode 100644
index 000000000..61b452272
--- /dev/null
+++ b/block/blk-zoned.c
@@ -0,0 +1,565 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Zoned block device handling
+ *
+ * Copyright (c) 2015, Hannes Reinecke
+ * Copyright (c) 2015, SUSE Linux GmbH
+ *
+ * Copyright (c) 2016, Damien Le Moal
+ * Copyright (c) 2016, Western Digital
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/rbtree.h>
+#include <linux/blkdev.h>
+#include <linux/blk-mq.h>
+#include <linux/mm.h>
+#include <linux/vmalloc.h>
+#include <linux/sched/mm.h>
+
+#include "blk.h"
+
+#define ZONE_COND_NAME(name) [BLK_ZONE_COND_##name] = #name
+static const char *const zone_cond_name[] = {
+ ZONE_COND_NAME(NOT_WP),
+ ZONE_COND_NAME(EMPTY),
+ ZONE_COND_NAME(IMP_OPEN),
+ ZONE_COND_NAME(EXP_OPEN),
+ ZONE_COND_NAME(CLOSED),
+ ZONE_COND_NAME(READONLY),
+ ZONE_COND_NAME(FULL),
+ ZONE_COND_NAME(OFFLINE),
+};
+#undef ZONE_COND_NAME
+
+/**
+ * blk_zone_cond_str - Return string XXX in BLK_ZONE_COND_XXX.
+ * @zone_cond: BLK_ZONE_COND_XXX.
+ *
+ * Description: Centralize block layer function to convert BLK_ZONE_COND_XXX
+ * into string format. Useful in the debugging and tracing zone conditions. For
+ * invalid BLK_ZONE_COND_XXX it returns string "UNKNOWN".
+ */
+const char *blk_zone_cond_str(enum blk_zone_cond zone_cond)
+{
+ static const char *zone_cond_str = "UNKNOWN";
+
+ if (zone_cond < ARRAY_SIZE(zone_cond_name) && zone_cond_name[zone_cond])
+ zone_cond_str = zone_cond_name[zone_cond];
+
+ return zone_cond_str;
+}
+EXPORT_SYMBOL_GPL(blk_zone_cond_str);
+
+static inline sector_t blk_zone_start(struct request_queue *q,
+ sector_t sector)
+{
+ sector_t zone_mask = blk_queue_zone_sectors(q) - 1;
+
+ return sector & ~zone_mask;
+}
+
+/*
+ * Return true if a request is a write requests that needs zone write locking.
+ */
+bool blk_req_needs_zone_write_lock(struct request *rq)
+{
+ if (!rq->q->seq_zones_wlock)
+ return false;
+
+ if (blk_rq_is_passthrough(rq))
+ return false;
+
+ switch (req_op(rq)) {
+ case REQ_OP_WRITE_ZEROES:
+ case REQ_OP_WRITE_SAME:
+ case REQ_OP_WRITE:
+ return blk_rq_zone_is_seq(rq);
+ default:
+ return false;
+ }
+}
+EXPORT_SYMBOL_GPL(blk_req_needs_zone_write_lock);
+
+bool blk_req_zone_write_trylock(struct request *rq)
+{
+ unsigned int zno = blk_rq_zone_no(rq);
+
+ if (test_and_set_bit(zno, rq->q->seq_zones_wlock))
+ return false;
+
+ WARN_ON_ONCE(rq->rq_flags & RQF_ZONE_WRITE_LOCKED);
+ rq->rq_flags |= RQF_ZONE_WRITE_LOCKED;
+
+ return true;
+}
+EXPORT_SYMBOL_GPL(blk_req_zone_write_trylock);
+
+void __blk_req_zone_write_lock(struct request *rq)
+{
+ if (WARN_ON_ONCE(test_and_set_bit(blk_rq_zone_no(rq),
+ rq->q->seq_zones_wlock)))
+ return;
+
+ WARN_ON_ONCE(rq->rq_flags & RQF_ZONE_WRITE_LOCKED);
+ rq->rq_flags |= RQF_ZONE_WRITE_LOCKED;
+}
+EXPORT_SYMBOL_GPL(__blk_req_zone_write_lock);
+
+void __blk_req_zone_write_unlock(struct request *rq)
+{
+ rq->rq_flags &= ~RQF_ZONE_WRITE_LOCKED;
+ if (rq->q->seq_zones_wlock)
+ WARN_ON_ONCE(!test_and_clear_bit(blk_rq_zone_no(rq),
+ rq->q->seq_zones_wlock));
+}
+EXPORT_SYMBOL_GPL(__blk_req_zone_write_unlock);
+
+/**
+ * blkdev_nr_zones - Get number of zones
+ * @disk: Target gendisk
+ *
+ * Return the total number of zones of a zoned block device. For a block
+ * device without zone capabilities, the number of zones is always 0.
+ */
+unsigned int blkdev_nr_zones(struct gendisk *disk)
+{
+ sector_t zone_sectors = blk_queue_zone_sectors(disk->queue);
+
+ if (!blk_queue_is_zoned(disk->queue))
+ return 0;
+ return (get_capacity(disk) + zone_sectors - 1) >> ilog2(zone_sectors);
+}
+EXPORT_SYMBOL_GPL(blkdev_nr_zones);
+
+/**
+ * blkdev_report_zones - Get zones information
+ * @bdev: Target block device
+ * @sector: Sector from which to report zones
+ * @nr_zones: Maximum number of zones to report
+ * @cb: Callback function called for each reported zone
+ * @data: Private data for the callback
+ *
+ * Description:
+ * Get zone information starting from the zone containing @sector for at most
+ * @nr_zones, and call @cb for each zone reported by the device.
+ * To report all zones in a device starting from @sector, the BLK_ALL_ZONES
+ * constant can be passed to @nr_zones.
+ * Returns the number of zones reported by the device, or a negative errno
+ * value in case of failure.
+ *
+ * Note: The caller must use memalloc_noXX_save/restore() calls to control
+ * memory allocations done within this function.
+ */
+int blkdev_report_zones(struct block_device *bdev, sector_t sector,
+ unsigned int nr_zones, report_zones_cb cb, void *data)
+{
+ struct gendisk *disk = bdev->bd_disk;
+ sector_t capacity = get_capacity(disk);
+
+ if (!blk_queue_is_zoned(bdev_get_queue(bdev)) ||
+ WARN_ON_ONCE(!disk->fops->report_zones))
+ return -EOPNOTSUPP;
+
+ if (!nr_zones || sector >= capacity)
+ return 0;
+
+ return disk->fops->report_zones(disk, sector, nr_zones, cb, data);
+}
+EXPORT_SYMBOL_GPL(blkdev_report_zones);
+
+static inline bool blkdev_allow_reset_all_zones(struct block_device *bdev,
+ sector_t sector,
+ sector_t nr_sectors)
+{
+ if (!blk_queue_zone_resetall(bdev_get_queue(bdev)))
+ return false;
+
+ /*
+ * REQ_OP_ZONE_RESET_ALL can be executed only if the number of sectors
+ * of the applicable zone range is the entire disk.
+ */
+ return !sector && nr_sectors == get_capacity(bdev->bd_disk);
+}
+
+/**
+ * blkdev_zone_mgmt - Execute a zone management operation on a range of zones
+ * @bdev: Target block device
+ * @op: Operation to be performed on the zones
+ * @sector: Start sector of the first zone to operate on
+ * @nr_sectors: Number of sectors, should be at least the length of one zone and
+ * must be zone size aligned.
+ * @gfp_mask: Memory allocation flags (for bio_alloc)
+ *
+ * Description:
+ * Perform the specified operation on the range of zones specified by
+ * @sector..@sector+@nr_sectors. Specifying the entire disk sector range
+ * is valid, but the specified range should not contain conventional zones.
+ * The operation to execute on each zone can be a zone reset, open, close
+ * or finish request.
+ */
+int blkdev_zone_mgmt(struct block_device *bdev, enum req_opf op,
+ sector_t sector, sector_t nr_sectors,
+ gfp_t gfp_mask)
+{
+ struct request_queue *q = bdev_get_queue(bdev);
+ sector_t zone_sectors = blk_queue_zone_sectors(q);
+ sector_t capacity = get_capacity(bdev->bd_disk);
+ sector_t end_sector = sector + nr_sectors;
+ struct bio *bio = NULL;
+ int ret;
+
+ if (!blk_queue_is_zoned(q))
+ return -EOPNOTSUPP;
+
+ if (bdev_read_only(bdev))
+ return -EPERM;
+
+ if (!op_is_zone_mgmt(op))
+ return -EOPNOTSUPP;
+
+ if (end_sector <= sector || end_sector > capacity)
+ /* Out of range */
+ return -EINVAL;
+
+ /* Check alignment (handle eventual smaller last zone) */
+ if (sector & (zone_sectors - 1))
+ return -EINVAL;
+
+ if ((nr_sectors & (zone_sectors - 1)) && end_sector != capacity)
+ return -EINVAL;
+
+ while (sector < end_sector) {
+ bio = blk_next_bio(bio, 0, gfp_mask);
+ bio_set_dev(bio, bdev);
+
+ /*
+ * Special case for the zone reset operation that reset all
+ * zones, this is useful for applications like mkfs.
+ */
+ if (op == REQ_OP_ZONE_RESET &&
+ blkdev_allow_reset_all_zones(bdev, sector, nr_sectors)) {
+ bio->bi_opf = REQ_OP_ZONE_RESET_ALL | REQ_SYNC;
+ break;
+ }
+
+ bio->bi_opf = op | REQ_SYNC;
+ bio->bi_iter.bi_sector = sector;
+ sector += zone_sectors;
+
+ /* This may take a while, so be nice to others */
+ cond_resched();
+ }
+
+ ret = submit_bio_wait(bio);
+ bio_put(bio);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(blkdev_zone_mgmt);
+
+struct zone_report_args {
+ struct blk_zone __user *zones;
+};
+
+static int blkdev_copy_zone_to_user(struct blk_zone *zone, unsigned int idx,
+ void *data)
+{
+ struct zone_report_args *args = data;
+
+ if (copy_to_user(&args->zones[idx], zone, sizeof(struct blk_zone)))
+ return -EFAULT;
+ return 0;
+}
+
+/*
+ * BLKREPORTZONE ioctl processing.
+ * Called from blkdev_ioctl.
+ */
+int blkdev_report_zones_ioctl(struct block_device *bdev, fmode_t mode,
+ unsigned int cmd, unsigned long arg)
+{
+ void __user *argp = (void __user *)arg;
+ struct zone_report_args args;
+ struct request_queue *q;
+ struct blk_zone_report rep;
+ int ret;
+
+ if (!argp)
+ return -EINVAL;
+
+ q = bdev_get_queue(bdev);
+ if (!q)
+ return -ENXIO;
+
+ if (!blk_queue_is_zoned(q))
+ return -ENOTTY;
+
+ if (copy_from_user(&rep, argp, sizeof(struct blk_zone_report)))
+ return -EFAULT;
+
+ if (!rep.nr_zones)
+ return -EINVAL;
+
+ args.zones = argp + sizeof(struct blk_zone_report);
+ ret = blkdev_report_zones(bdev, rep.sector, rep.nr_zones,
+ blkdev_copy_zone_to_user, &args);
+ if (ret < 0)
+ return ret;
+
+ rep.nr_zones = ret;
+ rep.flags = BLK_ZONE_REP_CAPACITY;
+ if (copy_to_user(argp, &rep, sizeof(struct blk_zone_report)))
+ return -EFAULT;
+ return 0;
+}
+
+static int blkdev_truncate_zone_range(struct block_device *bdev, fmode_t mode,
+ const struct blk_zone_range *zrange)
+{
+ loff_t start, end;
+
+ if (zrange->sector + zrange->nr_sectors <= zrange->sector ||
+ zrange->sector + zrange->nr_sectors > get_capacity(bdev->bd_disk))
+ /* Out of range */
+ return -EINVAL;
+
+ start = zrange->sector << SECTOR_SHIFT;
+ end = ((zrange->sector + zrange->nr_sectors) << SECTOR_SHIFT) - 1;
+
+ return truncate_bdev_range(bdev, mode, start, end);
+}
+
+/*
+ * BLKRESETZONE, BLKOPENZONE, BLKCLOSEZONE and BLKFINISHZONE ioctl processing.
+ * Called from blkdev_ioctl.
+ */
+int blkdev_zone_mgmt_ioctl(struct block_device *bdev, fmode_t mode,
+ unsigned int cmd, unsigned long arg)
+{
+ void __user *argp = (void __user *)arg;
+ struct request_queue *q;
+ struct blk_zone_range zrange;
+ enum req_opf op;
+ int ret;
+
+ if (!argp)
+ return -EINVAL;
+
+ q = bdev_get_queue(bdev);
+ if (!q)
+ return -ENXIO;
+
+ if (!blk_queue_is_zoned(q))
+ return -ENOTTY;
+
+ if (!(mode & FMODE_WRITE))
+ return -EBADF;
+
+ if (copy_from_user(&zrange, argp, sizeof(struct blk_zone_range)))
+ return -EFAULT;
+
+ switch (cmd) {
+ case BLKRESETZONE:
+ op = REQ_OP_ZONE_RESET;
+
+ /* Invalidate the page cache, including dirty pages. */
+ ret = blkdev_truncate_zone_range(bdev, mode, &zrange);
+ if (ret)
+ return ret;
+ break;
+ case BLKOPENZONE:
+ op = REQ_OP_ZONE_OPEN;
+ break;
+ case BLKCLOSEZONE:
+ op = REQ_OP_ZONE_CLOSE;
+ break;
+ case BLKFINISHZONE:
+ op = REQ_OP_ZONE_FINISH;
+ break;
+ default:
+ return -ENOTTY;
+ }
+
+ ret = blkdev_zone_mgmt(bdev, op, zrange.sector, zrange.nr_sectors,
+ GFP_KERNEL);
+
+ /*
+ * Invalidate the page cache again for zone reset: writes can only be
+ * direct for zoned devices so concurrent writes would not add any page
+ * to the page cache after/during reset. The page cache may be filled
+ * again due to concurrent reads though and dropping the pages for
+ * these is fine.
+ */
+ if (!ret && cmd == BLKRESETZONE)
+ ret = blkdev_truncate_zone_range(bdev, mode, &zrange);
+
+ return ret;
+}
+
+static inline unsigned long *blk_alloc_zone_bitmap(int node,
+ unsigned int nr_zones)
+{
+ return kcalloc_node(BITS_TO_LONGS(nr_zones), sizeof(unsigned long),
+ GFP_NOIO, node);
+}
+
+void blk_queue_free_zone_bitmaps(struct request_queue *q)
+{
+ kfree(q->conv_zones_bitmap);
+ q->conv_zones_bitmap = NULL;
+ kfree(q->seq_zones_wlock);
+ q->seq_zones_wlock = NULL;
+}
+
+struct blk_revalidate_zone_args {
+ struct gendisk *disk;
+ unsigned long *conv_zones_bitmap;
+ unsigned long *seq_zones_wlock;
+ unsigned int nr_zones;
+ sector_t zone_sectors;
+ sector_t sector;
+};
+
+/*
+ * Helper function to check the validity of zones of a zoned block device.
+ */
+static int blk_revalidate_zone_cb(struct blk_zone *zone, unsigned int idx,
+ void *data)
+{
+ struct blk_revalidate_zone_args *args = data;
+ struct gendisk *disk = args->disk;
+ struct request_queue *q = disk->queue;
+ sector_t capacity = get_capacity(disk);
+
+ /*
+ * All zones must have the same size, with the exception on an eventual
+ * smaller last zone.
+ */
+ if (zone->start == 0) {
+ if (zone->len == 0 || !is_power_of_2(zone->len)) {
+ pr_warn("%s: Invalid zoned device with non power of two zone size (%llu)\n",
+ disk->disk_name, zone->len);
+ return -ENODEV;
+ }
+
+ args->zone_sectors = zone->len;
+ args->nr_zones = (capacity + zone->len - 1) >> ilog2(zone->len);
+ } else if (zone->start + args->zone_sectors < capacity) {
+ if (zone->len != args->zone_sectors) {
+ pr_warn("%s: Invalid zoned device with non constant zone size\n",
+ disk->disk_name);
+ return -ENODEV;
+ }
+ } else {
+ if (zone->len > args->zone_sectors) {
+ pr_warn("%s: Invalid zoned device with larger last zone size\n",
+ disk->disk_name);
+ return -ENODEV;
+ }
+ }
+
+ /* Check for holes in the zone report */
+ if (zone->start != args->sector) {
+ pr_warn("%s: Zone gap at sectors %llu..%llu\n",
+ disk->disk_name, args->sector, zone->start);
+ return -ENODEV;
+ }
+
+ /* Check zone type */
+ switch (zone->type) {
+ case BLK_ZONE_TYPE_CONVENTIONAL:
+ if (!args->conv_zones_bitmap) {
+ args->conv_zones_bitmap =
+ blk_alloc_zone_bitmap(q->node, args->nr_zones);
+ if (!args->conv_zones_bitmap)
+ return -ENOMEM;
+ }
+ set_bit(idx, args->conv_zones_bitmap);
+ break;
+ case BLK_ZONE_TYPE_SEQWRITE_REQ:
+ case BLK_ZONE_TYPE_SEQWRITE_PREF:
+ if (!args->seq_zones_wlock) {
+ args->seq_zones_wlock =
+ blk_alloc_zone_bitmap(q->node, args->nr_zones);
+ if (!args->seq_zones_wlock)
+ return -ENOMEM;
+ }
+ break;
+ default:
+ pr_warn("%s: Invalid zone type 0x%x at sectors %llu\n",
+ disk->disk_name, (int)zone->type, zone->start);
+ return -ENODEV;
+ }
+
+ args->sector += zone->len;
+ return 0;
+}
+
+/**
+ * blk_revalidate_disk_zones - (re)allocate and initialize zone bitmaps
+ * @disk: Target disk
+ * @update_driver_data: Callback to update driver data on the frozen disk
+ *
+ * Helper function for low-level device drivers to (re) allocate and initialize
+ * a disk request queue zone bitmaps. This functions should normally be called
+ * within the disk ->revalidate method for blk-mq based drivers. For BIO based
+ * drivers only q->nr_zones needs to be updated so that the sysfs exposed value
+ * is correct.
+ * If the @update_driver_data callback function is not NULL, the callback is
+ * executed with the device request queue frozen after all zones have been
+ * checked.
+ */
+int blk_revalidate_disk_zones(struct gendisk *disk,
+ void (*update_driver_data)(struct gendisk *disk))
+{
+ struct request_queue *q = disk->queue;
+ struct blk_revalidate_zone_args args = {
+ .disk = disk,
+ };
+ unsigned int noio_flag;
+ int ret;
+
+ if (WARN_ON_ONCE(!blk_queue_is_zoned(q)))
+ return -EIO;
+ if (WARN_ON_ONCE(!queue_is_mq(q)))
+ return -EIO;
+
+ if (!get_capacity(disk))
+ return -EIO;
+
+ /*
+ * Ensure that all memory allocations in this context are done as if
+ * GFP_NOIO was specified.
+ */
+ noio_flag = memalloc_noio_save();
+ ret = disk->fops->report_zones(disk, 0, UINT_MAX,
+ blk_revalidate_zone_cb, &args);
+ memalloc_noio_restore(noio_flag);
+
+ /*
+ * Install the new bitmaps and update nr_zones only once the queue is
+ * stopped and all I/Os are completed (i.e. a scheduler is not
+ * referencing the bitmaps).
+ */
+ blk_mq_freeze_queue(q);
+ if (ret >= 0) {
+ blk_queue_chunk_sectors(q, args.zone_sectors);
+ q->nr_zones = args.nr_zones;
+ swap(q->seq_zones_wlock, args.seq_zones_wlock);
+ swap(q->conv_zones_bitmap, args.conv_zones_bitmap);
+ if (update_driver_data)
+ update_driver_data(disk);
+ ret = 0;
+ } else {
+ pr_warn("%s: failed to revalidate zones\n", disk->disk_name);
+ blk_queue_free_zone_bitmaps(q);
+ }
+ blk_mq_unfreeze_queue(q);
+
+ kfree(args.seq_zones_wlock);
+ kfree(args.conv_zones_bitmap);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(blk_revalidate_disk_zones);