To be able to split a write into properly sized zone append commands,
we need a queue_limits structure that contains the least common
denominator suitable for all devices.
Signed-off-by: Christoph Hellwig <hch@xxxxxx>
---
fs/btrfs/fs.h | 5 ++++-
fs/btrfs/zoned.c | 52 ++++++++++++++++++++++++------------------------
fs/btrfs/zoned.h | 1 -
3 files changed, 30 insertions(+), 28 deletions(-)
diff --git a/fs/btrfs/fs.h b/fs/btrfs/fs.h
index a749367e5ae2a..d5224df7468b8 100644
--- a/fs/btrfs/fs.h
+++ b/fs/btrfs/fs.h
@@ -3,6 +3,7 @@
#ifndef BTRFS_FS_H
#define BTRFS_FS_H
+#include <linux/blkdev.h>
#include <linux/fs.h>
#include <linux/btrfs_tree.h>
#include <linux/sizes.h>
@@ -736,8 +737,10 @@ struct btrfs_fs_info {
*/
u64 zone_size;
- /* Max size to emit ZONE_APPEND write command */
+ /* Constraints for ZONE_APPEND commands: */
+ struct queue_limits limits;
u64 max_zone_append_size;
+
struct mutex zoned_meta_io_lock;
spinlock_t treelog_bg_lock;
u64 treelog_bg;
diff --git a/fs/btrfs/zoned.c b/fs/btrfs/zoned.c
index 04a16d70ed7a5..2d14f5ad79a39 100644
--- a/fs/btrfs/zoned.c
+++ b/fs/btrfs/zoned.c
@@ -418,25 +418,6 @@ int btrfs_get_dev_zone_info(struct btrfs_device *device, bool populate_cache)
nr_sectors = bdev_nr_sectors(bdev);
zone_info->zone_size_shift = ilog2(zone_info->zone_size);
zone_info->nr_zones = nr_sectors >> ilog2(zone_sectors);
- /*
- * We limit max_zone_append_size also by max_segments *
- * PAGE_SIZE. Technically, we can have multiple pages per segment. But,
- * since btrfs adds the pages one by one to a bio, and btrfs cannot
- * increase the metadata reservation even if it increases the number of
- * extents, it is safe to stick with the limit.
- *
- * With the zoned emulation, we can have non-zoned device on the zoned
- * mode. In this case, we don't have a valid max zone append size. So,
- * use max_segments * PAGE_SIZE as the pseudo max_zone_append_size.
- */
- if (bdev_is_zoned(bdev)) {
- zone_info->max_zone_append_size = min_t(u64,
- (u64)bdev_max_zone_append_sectors(bdev) << SECTOR_SHIFT,
- (u64)bdev_max_segments(bdev) << PAGE_SHIFT);
- } else {
- zone_info->max_zone_append_size =
- (u64)bdev_max_segments(bdev) << PAGE_SHIFT;
- }
if (!IS_ALIGNED(nr_sectors, zone_sectors))
zone_info->nr_zones++;
@@ -714,9 +695,9 @@ static int btrfs_check_for_zoned_device(struct btrfs_fs_info *fs_info)
int btrfs_check_zoned_mode(struct btrfs_fs_info *fs_info)
{
+ struct queue_limits *lim = &fs_info->limits;
struct btrfs_device *device;
u64 zone_size = 0;
- u64 max_zone_append_size = 0;
int ret;
/*
@@ -726,6 +707,8 @@ int btrfs_check_zoned_mode(struct btrfs_fs_info *fs_info)
if (!btrfs_fs_incompat(fs_info, ZONED))
return btrfs_check_for_zoned_device(fs_info);
+ blk_set_stacking_limits(lim);
+
list_for_each_entry(device, &fs_info->fs_devices->devices, dev_list) {
struct btrfs_zoned_device_info *zone_info = device->zone_info;
@@ -740,10 +723,17 @@ int btrfs_check_zoned_mode(struct btrfs_fs_info *fs_info)
zone_info->zone_size, zone_size);
return -EINVAL;
}
- if (!max_zone_append_size ||
- (zone_info->max_zone_append_size &&
- zone_info->max_zone_append_size < max_zone_append_size))
- max_zone_append_size = zone_info->max_zone_append_size;
+
+ /*
+ * With the zoned emulation, we can have non-zoned device on the
+ * zoned mode. In this case, we don't have a valid max zone
+ * append size.
+ */
+ if (bdev_is_zoned(device->bdev)) {
+ blk_stack_limits(lim,
+ &bdev_get_queue(device->bdev)->limits,
+ 0);
+ }
}
/*
@@ -764,8 +754,18 @@ int btrfs_check_zoned_mode(struct btrfs_fs_info *fs_info)
}
fs_info->zone_size = zone_size;
- fs_info->max_zone_append_size = ALIGN_DOWN(max_zone_append_size,
- fs_info->sectorsize);
+ /*
+ * Also limit max_zone_append_size by max_segments * PAGE_SIZE.
+ * Technically, we can have multiple pages per segment. But,
+ * since btrfs adds the pages one by one to a bio, and btrfs cannot
+ * increase the metadata reservation even if it increases the number of
+ * extents, it is safe to stick with the limit.
+ */
+ fs_info->max_zone_append_size = ALIGN_DOWN(
+ min3((u64)lim->max_zone_append_sectors << SECTOR_SHIFT,
+ (u64)lim->max_sectors << SECTOR_SHIFT,
+ (u64)lim->max_segments << PAGE_SHIFT),
+ fs_info->sectorsize);
fs_info->fs_devices->chunk_alloc_policy = BTRFS_CHUNK_ALLOC_ZONED;
if (fs_info->max_zone_append_size < fs_info->max_extent_size)
fs_info->max_extent_size = fs_info->max_zone_append_size;
diff --git a/fs/btrfs/zoned.h b/fs/btrfs/zoned.h
index bc93a740e7cf3..f25f332b77285 100644
--- a/fs/btrfs/zoned.h
+++ b/fs/btrfs/zoned.h
@@ -20,7 +20,6 @@ struct btrfs_zoned_device_info {
*/
u64 zone_size;
u8 zone_size_shift;
- u64 max_zone_append_size;
u32 nr_zones;
unsigned int max_active_zones;
atomic_t active_zones_left;
--
2.30.2
