Tomasz Zawadzki 1350922d09 bdev/ocf: take additional reference for ocf_cache ... Fixes #1498 When shutting down the application, it was possible to reference stale ocf_cache pointer. This was the case when two or more vbdev_ocf devices were based on top of single cache bdev. This issue did not occur outside of the shutdown case, since RPC only allows deletion of the vbdev_ocf. This erases on disk metadata and next run of the application, would not detect such vbdev_ocf. Shutdown meanwhile works different, by first stopping the instance of running "ocf_mngt_cache" and later detaching "core" devices (the ones being cached). This prevented erasing the on disk metadata and allowed for restarted application to detect vbdev_ocf. See patch (1292ef2) for details. Since references to ocf_cache are copied between vbdev_ocf [see start_cache()], the reference count inside ocf_cache was limited to original ocf_mngt_cache_start() and management queue creation. First call into ocf_mngt_cache_stop() released all references to ocf_cache. Leaving other vbdev_ocfs pointing to released memory. This patch works around this issue by increasing ref cnt on ocf_cache for each vbdev based on top of it. It allows to call into ocf_mngt_cache_stop(), but not release the memory for ocf_cache until last vbdev. Note: A proper redesign here is in order: - either rearranging structures to be based around single ocf_cache, rather than multiple vbdev_ocf instances - better use of OCF API to reduce book keeping logic in vbdev There are plans to implement detach/attach in RPC, so it should be a focus during that effort. Signed-off-by: Tomasz Zawadzki <tomasz.zawadzki@intel.com> Change-Id: I560a7fbb1c052bf53970e655bdb60803c561a252 Reviewed-on: https://review.spdk.io/gerrit/c/spdk/spdk/+/3574 Tested-by: SPDK CI Jenkins <sys_sgci@intel.com> Reviewed-by: Vitaliy Mysak <vitaliy.mysak@intel.com> Reviewed-by: Jim Harris <james.r.harris@intel.com> Reviewed-by: Ben Walker <benjamin.walker@intel.com>		2020-07-30 04:02:08 +00:00
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accel	accel: add API to cancel a batch sequence	2020-07-27 22:43:40 +00:00
bdev	bdev/ocf: take additional reference for ocf_cache	2020-07-30 04:02:08 +00:00
blob	lib/bdev: Add spdk_bdev_abort API	2020-06-08 09:28:27 +00:00
blobfs	mk/lib: add a check that major and minor version is set for libs.	2020-05-21 09:19:00 +00:00
env_dpdk	mk/lib: add a check that major and minor version is set for libs.	2020-05-21 09:19:00 +00:00
event	sock: Save socket subsystem configuration in JSON format	2020-07-13 08:40:15 +00:00
sock	sock: Add sock_impl option to disable zero copy on send	2020-07-24 00:30:45 +00:00
Makefile	global: rename copy to accel	2020-02-18 08:05:34 +00:00