diff mbox series

[18/26] btrfs-progs: zoned: support zero out on zoned block device

Message ID 9740fbfd8cb582ac0f961bd96a4a8dadb10c8a44.1619416549.git.naohiro.aota@wdc.com (mailing list archive)
State New, archived
Headers show
Series btrfs-progs: zoned: zoned block device support | expand

Commit Message

Naohiro Aota April 26, 2021, 6:27 a.m. UTC
If we zero out a region in a sequential write required zone, we cannot
write to the region until we reset the zone. Thus, we must prohibit zeroing
out to a sequential write required zone.

zero_dev_clamped() is modified to take the zone information and it calls
zero_zone_blocks() if the device is host managed to avoid writing to
sequential write required zones.

Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
---
 common/device-utils.c | 14 +++++++++-----
 common/device-utils.h |  1 +
 kernel-shared/zoned.c | 28 ++++++++++++++++++++++++++++
 kernel-shared/zoned.h |  9 +++++++++
 4 files changed, 47 insertions(+), 5 deletions(-)
diff mbox series

Patch

diff --git a/common/device-utils.c b/common/device-utils.c
index 2687f1884619..c1006c501555 100644
--- a/common/device-utils.c
+++ b/common/device-utils.c
@@ -67,7 +67,7 @@  int discard_blocks(int fd, u64 start, u64 len)
 	return 0;
 }
 
-static int zero_blocks(int fd, off_t start, size_t len)
+int zero_blocks(int fd, off_t start, size_t len)
 {
 	char *buf = malloc(len);
 	int ret = 0;
@@ -86,7 +86,8 @@  static int zero_blocks(int fd, off_t start, size_t len)
 #define ZERO_DEV_BYTES SZ_2M
 
 /* don't write outside the device by clamping the region to the device size */
-static int zero_dev_clamped(int fd, off_t start, ssize_t len, u64 dev_size)
+static int zero_dev_clamped(int fd, struct btrfs_zoned_device_info *zinfo,
+			    off_t start, ssize_t len, u64 dev_size)
 {
 	off_t end = max(start, start + len);
 
@@ -99,6 +100,9 @@  static int zero_dev_clamped(int fd, off_t start, ssize_t len, u64 dev_size)
 	start = min_t(u64, start, dev_size);
 	end = min_t(u64, end, dev_size);
 
+	if (zinfo && zinfo->model == ZONED_HOST_MANAGED)
+		return zero_zone_blocks(fd, zinfo, start, end - start);
+
 	return zero_blocks(fd, start, end - start);
 }
 
@@ -209,12 +213,12 @@  int btrfs_prepare_device(int fd, const char *file, u64 *block_count_ret,
 		}
 	}
 
-	ret = zero_dev_clamped(fd, 0, ZERO_DEV_BYTES, block_count);
+	ret = zero_dev_clamped(fd, zinfo, 0, ZERO_DEV_BYTES, block_count);
 	for (i = 0 ; !ret && i < BTRFS_SUPER_MIRROR_MAX; i++)
-		ret = zero_dev_clamped(fd, btrfs_sb_offset(i),
+		ret = zero_dev_clamped(fd, zinfo, btrfs_sb_offset(i),
 				       BTRFS_SUPER_INFO_SIZE, block_count);
 	if (!ret && (opflags & PREP_DEVICE_ZERO_END))
-		ret = zero_dev_clamped(fd, block_count - ZERO_DEV_BYTES,
+		ret = zero_dev_clamped(fd, zinfo, block_count - ZERO_DEV_BYTES,
 				       ZERO_DEV_BYTES, block_count);
 
 	if (ret < 0) {
diff --git a/common/device-utils.h b/common/device-utils.h
index e7e638a57eb2..6eee3270e0c7 100644
--- a/common/device-utils.h
+++ b/common/device-utils.h
@@ -26,6 +26,7 @@ 
 #define	PREP_DEVICE_ZONED	(1U << 3)
 
 int discard_blocks(int fd, u64 start, u64 len);
+int zero_blocks(int fd, off_t start, size_t len);
 u64 get_partition_size(const char *dev);
 u64 disk_size(const char *path);
 u64 btrfs_device_size(int fd, struct stat *st);
diff --git a/kernel-shared/zoned.c b/kernel-shared/zoned.c
index ba1399cce04d..3c476eebf004 100644
--- a/kernel-shared/zoned.c
+++ b/kernel-shared/zoned.c
@@ -394,6 +394,34 @@  int btrfs_reset_all_zones(int fd, struct btrfs_zoned_device_info *zinfo)
 	return fsync(fd);
 }
 
+int zero_zone_blocks(int fd, struct btrfs_zoned_device_info *zinfo, off_t start,
+		     size_t len)
+{
+	size_t zone_len = zinfo->zone_size;
+	off_t ofst = start;
+	size_t count;
+	int ret;
+
+	/* Make sure that zero_blocks does not write sequential zones */
+	while (len > 0) {
+		/* Limit zero_blocks to a single zone */
+		count = min_t(size_t, len, zone_len);
+		if (count > zone_len - (ofst & (zone_len - 1)))
+			count = zone_len - (ofst & (zone_len - 1));
+
+		if (!zone_is_sequential(zinfo, ofst)) {
+			ret = zero_blocks(fd, ofst, count);
+			if (ret != 0)
+				return ret;
+		}
+
+		len -= count;
+		ofst += count;
+	}
+
+	return 0;
+}
+
 static int sb_log_location(int fd, struct blk_zone *zones, int rw,
 			   u64 *bytenr_ret)
 {
diff --git a/kernel-shared/zoned.h b/kernel-shared/zoned.h
index 88831d2d787c..9e1ce3ae103f 100644
--- a/kernel-shared/zoned.h
+++ b/kernel-shared/zoned.h
@@ -92,6 +92,8 @@  bool btrfs_redirty_extent_buffer_for_zoned(struct btrfs_fs_info *fs_info,
 int btrfs_reset_chunk_zones(struct btrfs_fs_info *fs_info, u64 devid,
 			    u64 offset, u64 length);
 int btrfs_reset_all_zones(int fd, struct btrfs_zoned_device_info *zinfo);
+int zero_zone_blocks(int fd, struct btrfs_zoned_device_info *zinfo, off_t start,
+		     size_t len);
 #else
 #define sbread(fd, buf, offset) \
 	pread64(fd, buf, BTRFS_SUPER_INFO_SIZE, offset)
@@ -145,6 +147,13 @@  static inline int btrfs_reset_all_zones(int fd,
 	return -EOPNOTSUPP;
 }
 
+static inline int zero_zone_blocks(int fd,
+				   struct btrfs_zoned_device_info *zinfo,
+				   off_t start, size_t len)
+{
+	return -EOPNOTSUPP;
+}
+
 #endif /* BTRFS_ZONED */
 
 static inline bool btrfs_dev_is_sequential(struct btrfs_device *device, u64 pos)