On 23/06/28 03:51PM, Damien Le Moal wrote:
On 6/28/23 03:36, Nitesh Shetty wrote:
For direct block device opened with O_DIRECT, use copy_file_range to
issue device copy offload, and fallback to generic_copy_file_range incase
device copy offload capability is absent.
...if the device does not support copy offload or the device files are not open
with O_DIRECT.
No ?
Yes your right. We will fallback to generic_copy_file_range in either of
these cases.
Modify checks to allow bdevs to use copy_file_range.
Suggested-by: Ming Lei <ming.lei@xxxxxxxxxx>
Signed-off-by: Anuj Gupta <anuj20.g@xxxxxxxxxxx>
Signed-off-by: Nitesh Shetty <nj.shetty@xxxxxxxxxxx>
---
block/blk-lib.c | 26 ++++++++++++++++++++++++++
block/fops.c | 20 ++++++++++++++++++++
fs/read_write.c | 7 +++++--
include/linux/blkdev.h | 4 ++++
4 files changed, 55 insertions(+), 2 deletions(-)
diff --git a/block/blk-lib.c b/block/blk-lib.c
index 09e0d5d51d03..7d8e09a99254 100644
--- a/block/blk-lib.c
+++ b/block/blk-lib.c
@@ -473,6 +473,32 @@ ssize_t blkdev_copy_offload(
}
EXPORT_SYMBOL_GPL(blkdev_copy_offload);
+/* Copy source offset from source block device to destination block
+ * device. Returns the length of bytes copied.
+ */
Multi-line comment style: start with a "/*" line please.
acked
+ssize_t blkdev_copy_offload_failfast(
What is the "failfast" in the name for ?
We dont want failed copy offload IOs to fallback to block layer copy emulation.
We wanted a API to return error, if offload fails.
+ struct block_device *bdev_in, loff_t pos_in,
+ struct block_device *bdev_out, loff_t pos_out,
+ size_t len, gfp_t gfp_mask)
+{
+ struct request_queue *in_q = bdev_get_queue(bdev_in);
+ struct request_queue *out_q = bdev_get_queue(bdev_out);
+ ssize_t ret = 0;
You do not need this initialization.
we need this initialization, because __blkdev_copy_offload return number of
bytes copied or error value.
So we can not return 0, incase of success/partial completion.
blkdev_copy_offload_failfast is expected to return number of bytes copied.
+
+ if (blkdev_copy_sanity_check(bdev_in, pos_in, bdev_out, pos_out, len))
+ return 0;
+
+ if (blk_queue_copy(in_q) && blk_queue_copy(out_q)) {
Given that I think we do not allow copies between different devices, in_q and
out_q should always be the same, no ?
acked, will update this.
+ ret = __blkdev_copy_offload(bdev_in, pos_in, bdev_out, pos_out,
+ len, NULL, NULL, gfp_mask);
Same here. Why pass 2 bdevs if we only allow copies within the same device ?
acked, will update function arguments to take single bdev.
+ if (ret < 0)
+ return 0;
+ }
+
+ return ret;
return 0;
Nack, explained above.
Thank you,
Nitesh Shetty
