[3/7] scsi: target: Add helper to setup atomic values from block_device

Commit Message

Mike Christie Oct. 8, 2024, 2:03 a.m. UTC

This adds a helper function that sets up the atomic value based on a
block_device similar to what we do for unmap.

Signed-off-by: Mike Christie <[e-mail]>
---
 drivers/target/target_core_device.c  | 18 ++++++++++++++++++
 include/target/target_core_backend.h |  2 ++
 2 files changed, 20 insertions(+)

Patch

diff --git a/drivers/target/target_core_device.c b/drivers/target/target_core_device.c
index b709a64c0ff3..4741de3d1061 100644
--- a/drivers/target/target_core_device.c
+++ b/drivers/target/target_core_device.c
@@ -793,6 +793,24 @@  struct se_device *target_alloc_device(struct se_hba *hba, const char *name)
 	return dev;
 }
 
+void target_configure_write_atomic_from_bdev(struct se_dev_attrib *attrib,
+					     struct block_device *bdev)
+{
+	struct request_queue *q = bdev_get_queue(bdev);
+	int block_size = bdev_logical_block_size(bdev);
+
+	if (!bdev_can_atomic_write(bdev))
+		return;
+
+	attrib->atomic_supported = true;
+	attrib->atomic_max_len = queue_atomic_write_max_bytes(q) / block_size;
+	attrib->atomic_granularity = queue_atomic_write_unit_min_bytes(q) /
+								block_size;
+	attrib->atomic_max_with_boundary = 0;
+	attrib->atomic_max_boundary = 0;
+}
+EXPORT_SYMBOL_GPL(target_configure_write_atomic_from_bdev);
+
 /*
  * Check if the underlying struct block_device supports discard and if yes
  * configure the UNMAP parameters.
diff --git a/include/target/target_core_backend.h b/include/target/target_core_backend.h
index d394306f8f49..e32de80854b6 100644
--- a/include/target/target_core_backend.h
+++ b/include/target/target_core_backend.h
@@ -123,6 +123,8 @@  bool target_sense_desc_format(struct se_device *dev);
 sector_t target_to_linux_sector(struct se_device *dev, sector_t lb);
 bool target_configure_unmap_from_bdev(struct se_dev_attrib *attrib,
 				      struct block_device *bdev);
+void target_configure_write_atomic_from_bdev(struct se_dev_attrib *attrib,
+					     struct block_device *bdev);
 
 static inline bool target_dev_configured(struct se_device *se_dev)
 {