[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [Qemu-devel] [PATCH v2 14/20] nbd: Support BDRV_REQ_FUA
From: |
Max Reitz |
Subject: |
Re: [Qemu-devel] [PATCH v2 14/20] nbd: Support BDRV_REQ_FUA |
Date: |
Tue, 29 Mar 2016 15:44:34 +0200 |
User-agent: |
Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.7.0 |
On 29.03.2016 15:30, Kevin Wolf wrote:
> The NBD server already used to send a FUA flag when the writethrough
> mode was set. This code was a remnant from the times where protocol
> drivers actually had to implement writethrough modes. Since nowadays the
> block layer sends flushes in writethrough mode and non-root nodes are
> always writeback, this was mostly dead code - only mostly because if NBD
> was configured to be used without a format, we sent _both_ FUA and an
> explicit flush afterwards, which makes the code not technically dead,
> but useless overhead.
>
> This patch changes the code so that the block layer's FUA flag is
> recognised and translated into a NBD FUA flag. The additional flush is
> avoided now.
>
> Signed-off-by: Kevin Wolf <address@hidden>
> ---
> block/nbd-client.c | 13 +++++++------
> block/nbd-client.h | 2 +-
> block/nbd.c | 27 ++++++++++++++++++++++++++-
> 3 files changed, 34 insertions(+), 8 deletions(-)
Reviewed-by: Max Reitz <address@hidden>
signature.asc
Description: OpenPGP digital signature
- [Qemu-devel] [PATCH v2 00/20] block: Implement writethrough in BlockBackend, Kevin Wolf, 2016/03/29
- [Qemu-devel] [PATCH v2 01/20] block: Add bdrv_parse_cache_mode(), Kevin Wolf, 2016/03/29
- [Qemu-devel] [PATCH v2 04/20] qemu-img: Expand all BDRV_O_FLAGS uses, Kevin Wolf, 2016/03/29
- [Qemu-devel] [PATCH v2 02/20] qemu-nbd: Call blk_set_enable_write_cache() explicitly, Kevin Wolf, 2016/03/29
- [Qemu-devel] [PATCH v2 03/20] qemu-io: Call blk_set_enable_write_cache() explicitly, Kevin Wolf, 2016/03/29
- [Qemu-devel] [PATCH v2 07/20] block: blockdev_init(): Call blk_set_enable_write_cache() explicitly, Kevin Wolf, 2016/03/29
- [Qemu-devel] [PATCH v2 05/20] qemu-img: Call blk_set_enable_write_cache() explicitly, Kevin Wolf, 2016/03/29
- [Qemu-devel] [PATCH v2 06/20] xen_disk: Call blk_set_enable_write_cache() explicitly, Kevin Wolf, 2016/03/29
- [Qemu-devel] [PATCH v2 14/20] nbd: Support BDRV_REQ_FUA, Kevin Wolf, 2016/03/29
- Re: [Qemu-devel] [PATCH v2 14/20] nbd: Support BDRV_REQ_FUA,
Max Reitz <=
- [Qemu-devel] [PATCH v2 11/20] block/qapi: Use blk_enable_write_cache(), Kevin Wolf, 2016/03/29
- [Qemu-devel] [PATCH v2 16/20] block: Use bdrv_parse_cache_mode() in drive_init(), Kevin Wolf, 2016/03/29
- [Qemu-devel] [PATCH v2 10/20] block: Move enable_write_cache to BB level, Kevin Wolf, 2016/03/29
- [Qemu-devel] [PATCH v2 09/20] block: Handle flush error in bdrv_pwrite_sync(), Kevin Wolf, 2016/03/29
- [Qemu-devel] [PATCH v2 08/20] block: Always set writeback mode in blk_new_open(), Kevin Wolf, 2016/03/29
- [Qemu-devel] [PATCH v2 12/20] block: Introduce bdrv_co_writev_flags(), Kevin Wolf, 2016/03/29
- [Qemu-devel] [PATCH v2 15/20] raw: Support BDRV_REQ_FUA, Kevin Wolf, 2016/03/29
- [Qemu-devel] [PATCH v2 17/20] qemu-io: Use bdrv_parse_cache_mode() in reopen_f(), Kevin Wolf, 2016/03/29