Kenneth D. Merry 07aa4de131 Fix a problem with async notifications in the mpr(4) driver. ... This problem only occurs on versions of FreeBSD prior to the recent CAM locking changes. (i.e. stable/9 and older versions of stable/10) This change should be a no-op for head and stable/10. If a path isn't specified, xpt_register_async() will create a fully wildcarded path and acquire a lock (the XPT lock in older versions, and via xpt_path_lock() in newer versions) to call xpt_action() for the XPT_SASYNC_CB CCB. It will then drop the lock and if the requested event includes AC_FOUND_DEVICE or AC_PATH_REGISTERED, it will get the caller up to date with any device arrivals or path registrations. The issue is that before the locking changes, each SIM lock would get acquired in turn during the EDT tree traversal process. If a path is specified for xpt_register_async(), it won't acquire and drop its own lock, but instead expects the caller to hold its own SIM lock. That works for the first part of xpt_register_async(), but causes a recursive lock acquisition once the EDT traversal happens and it comes to the SIM in question. And it isn't possible to call xpt_action() without holding a SIM lock. The locking changes fix this by using the XPT topology lock for EDT traversal, so it is no longer an issue to hold the SIM lock while calling xpt_register_async(). The solution for FreeBSD versions before the locking changes is to request notification of all device arrivals (so we pass a NULL path into xpt_register_async()) and then filter out the arrivals that are not ours. MFC After: 3 days Sponsored by: Spectra Logic Corporation		2014-05-06 06:18:43 +00:00
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mpi
mpr_config.c
mpr_ioctl.h
mpr_mapping.c
mpr_mapping.h
mpr_pci.c
mpr_sas_lsi.c
mpr_sas.c	Fix a problem with async notifications in the mpr(4) driver.	2014-05-06 06:18:43 +00:00
mpr_sas.h
mpr_table.c
mpr_table.h
mpr_user.c
mpr.c
mprvar.h