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| author |   Nicholas Bellinger <nab@linux-iscsi.org> | 2013-01-29 22:10:06 -0800 |
|---|---|---|
| committer | Nicholas Bellinger <nab@linux-iscsi.org> | 2013-02-13 11:27:51 -0800 |
| commit | d0c8b259f8970d39354c1966853363345d401330 (patch) | |
| tree | e6739094ba5db9ca88038f0e047e83e82bf21088 /include/target | |
| parent | iscsi-target: make some temporary buffers larger (diff) | |
| download | linux-dev-d0c8b259f8970d39354c1966853363345d401330.tar.xz linux-dev-d0c8b259f8970d39354c1966853363345d401330.zip | |
target/iblock: Use backend REQ_FLUSH hint for WriteCacheEnabled status
This patch allows IBLOCK to check block hints in request_queue->flush_flags
when reporting current backend device WriteCacheEnabled status to a remote
SCSI initiator port.
This is done via a se_subsystem_api->get_write_cache() call instead of a
backend se_device creation time flag, as we expect REQ_FLUSH bits to possibly
change from an underlying blk_queue_flush() by the SCSI disk driver, or
internal raw struct block_device driver usage.
Also go ahead and update iblock_execute_rw() bio I/O path code to use
REQ_FLUSH + REQ_FUA hints when determining WRITE_FUA usage, and make SPC
emulation code use a spc_check_dev_wce() helper to handle both types of
cases for virtual backend subsystem drivers.
(asias: Drop unnecessary comparsion operators)
Reported-by: majianpeng <majianpeng@gmail.com>
Cc: majianpeng <majianpeng@gmail.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: James Bottomley <JBottomley@Parallels.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Diffstat (limited to 'include/target')
| -rw-r--r-- | include/target/target_core_backend.h | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/include/target/target_core_backend.h b/include/target/target_core_backend.h index 819b0fc45215..f9a80169775d 100644 --- a/include/target/target_core_backend.h +++ b/include/target/target_core_backend.h @@ -35,6 +35,7 @@ struct se_subsystem_api { u32 (*get_device_type)(struct se_device *); sector_t (*get_blocks)(struct se_device *); unsigned char *(*get_sense_buffer)(struct se_cmd *); + bool (*get_write_cache)(struct se_device *); }; struct sbc_ops { |