This is a duplicate variable reference in mrsas, so now this patch isolate atomic_ variable and relavent
function call using prefix mrsas_xx.
Issue was introduced in r272737.
MFC after: 2 weeks
Sponsored by: Avago Technology
E.g: If the user wants to create more than 64VD on a controller,
it is not possible on current firmware/driver.
New feature and requirement to support upto 256VD, firmware/driver/apps need changes.
In addition to that, there must be a backward compatibility of the new driver with the
older firmware and vice versa.
RAID map is the interface between Driver and FW to fetch all required
fields(attributes) for each Virtual Drives.
In the earlier design driver was using the FW copy of RAID map where as
in the new design the Driver will keep the RAID map copy of its own; on which
it will operate for any raid map access in fast path.
Local driver raid map copy will provide ease of access through out the code
and provide generic interface for future FW raid map changes.
For the backward compatibility driver will notify FW that it supports 256VD
to the FW in driver capability field.
Based on the controller properly returned by the FW, the Driver will know
whether it supports 256VD or not and will copy the RAID map accordingly.
At any given time, driver will always have old or new Raid map.
Reviewed by : ambrisko
MFC after : 2 weeks
Sponsored by: AVAGO Technologies
cards. LSI has been maintaining this driver outside of the FreeBSD
tree. It overlaps support of ThunderBolt and Invader cards that mfi(4)
supports. By default mfi(4) will attach to cards. If the tunable:
hw.mfi.mrsas_enable=1
is set then mfi(4) will not probe and attach to these newer cards and
allow mrsas(4) to attach. So by default this driver will not effect
a FreeBSD system unless mfi(4) is removed from the kernel or the
tunable is enabled.
mrsas(4) attaches disks to the CAM layer so it depends on CAM and devices
show up as /dev/daX. mfiutil(8) does not work with mrsas. The FreeBSD
version of MegaCli and StorCli from LSI do work with mrsas. It appears
that StorCli only works with mrsas. MegaCli appears to work with mfi(4)
and mrsas(4).
It would be good to add mfiutil(4) support to mrsas, emulations modes,
kernel logging, device aliases to ease the transition between mfi(4)
and mrsas(4).
Style issues should be resolved by LSI when they get committers approved.
The plan is get this driver in FreeBSD 9.3 to improve HW support.
Thanks to LSI for developing, testing and working with FreeBSD to
make this driver co-exist in FreeBSD. This improves the overall
support of MegaRAID SAS.
Submitted by: Kashyap Desai <Kashyap.Desai@lsi.com>
Reviewed by: scottl
MFC after: 3 days
Sponsored by: LSI
