megaraid_sas : Modify return value of megasas_issue_blocked_cmd() and wait_and_poll() to consider command status returned by firmware

This patch is rebased on top of recently sent 18 patches(submitted by me) for
megaraid_sas driver.

Change the return value of wait_and_poll() and megsas_issue_blocked_cmd()
based on MFI_STAT returned by firmware for that command. Earlier driver always
send return type based on command completion (but never check MFI_STAT_OK for
that command), so even if command is failed by firmware still driver will
return SUCCESS status from these functions wait_and_poll() and
megsas_issue_blocked_cmd() and if caller of these functions does not check
command status (MFI_STAT), then it may endup using invalid data returned in
DMA buffers(one of the example is megasas_ld_list_query DCMD). Best thing to
avoid this type of issue is do error handling and set proper return type from
caller function wait_and_poll() and megsas_issue_blocked_cmd().

The change proposed in this patch will fix the regression introduced in patch-
"90dc9d98 megaraid_sas : MFI MPT linked list corruption fix" inside function
megasas_ld_list_query().  Prior to this MFI MPT linked list corruption fix
patch, megasas_ld_list_query() function used to check DCMD status(returned by
firmware) but with this linked list corruption fix patch, DCMD status will not
be checked inside function megasas_ld_list_query() and introduced this issue
of wrong data being used by function megasas_ld_list_query().

Cc: <stable@vger.kernel.org>
Signed-off-by: NKashyap Desai <kashyap.desai@avagotech.com>
Signed-off-by: NSumit Saxena <sumit.saxena@avagotech.com>
Reviewed-by: NTomas Henzl <thenzl@redhat.com>
Signed-off-by: NJames Bottomley <JBottomley@Odin.com>

This adds endianness annotations to all data structures, and a few
variables directly referencing them.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NSumit Saxena <sumit.saxena@avagotech.com>
Reviewed-by: NHannes Reinecke <hare@suse.de>
Reviewed-by: NTomas Henzl <thenzl@redhat.com>
Signed-off-by: NJames Bottomley <JBottomley@Odin.com>

Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NSumit Saxena <sumit.saxena@avagotech.com>
Reviewed-by: NHannes Reinecke <hare@suse.de>
Reviewed-by: NTomas Henzl <thenzl@redhat.com>
Signed-off-by: NJames Bottomley <JBottomley@Odin.com>

This patch will add support for Single Server High Availability(SSHA) cluster
support.  Here is the short decsription of changes done to add support for
SSHA-

1) Host will send system's Unique ID based on DMI_PRODUCT_UUID to firmware.
2) Toggle the devhandle in LDIO path for Remote LDs.
Signed-off-by: NKashyap Desai <kashyap.desai@avagotech.com>
Signed-off-by: NSumit Saxena <sumit.saxena@avagotech.com>
Reviewed-by: NHannes Reinecke <hare@suse.de>
Reviewed-by: NTomas Henzl <thenzl@redhat.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJames Bottomley <JBottomley@Odin.com>

This patch will upgrade the driver version and add back the release date and
sysfs hook for the same.  Some internal applications uses sysfs parameter for
release date, so they were broken because of removal of release date from
sysfs.
Signed-off-by: NSumit Saxena <sumit.saxena@avagotech.com>
Reviewed-by: NHannes Reinecke <hare@suse.de>
Reviewed-by: NTomas Henzl <thenzl@redhat.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJames Bottomley <JBottomley@Odin.com>

megaraid_sas driver will use block layer provided tag for indexing internal
MPT frames to get any unique MPT frame tied with tag.  Each IO request
submitted from SCSI mid layer will get associated MPT frame from MPT framepool
(retrieved and return back using spinlock inside megaraid_sas driver's
submission/completion call back). Getting MPT frame from MPT Frame pool is
very expensive operation because of associated spin lock operation (spinlock
overhead increase on multi NUMA node). This type of locking in driver is very
expensive call considering each IO request need - Acquire and Release of the
same lock.

With this support, in IO path driver will directly provide the unique command
index(which is based on block layer tag) and will get the MPT frame tied to
the tag and this way driver can get rid off lock, which synchronizes the
access to MPT frame pool while fetching and returning MPT frame from the pool.

This support in driver provides siginificant performance improvement(on multi
NUMA node system)on latest upstream with SCSI.MQ as well as on existing linux
distributions.

Here is the data for test executed at Avago-
- IO Tool- FIO
- 4 Socket SMC server. (4 NUMA node server)
- 12 SSDs in JBOD mode .
- 4K Rand READ, QD=32
- SCSI MQ x86_64 (Latest Upstream kernel)
- upto 300% Performance Improvement.

If IOs are running on single Node, perfromance gain is less, but as soon as
increase number of nodes, performance improvement is significant. IOs running
on all 4 NUMA nodes, with this patch applied IOPs observed was 1170K vs 344K
IOPs seen without this patch.

Logically, there are two parts of this patch- 1) Block layer tag support 2)
changes in calling convention of return_cmd.  part 2 will revert the changes
done by patch- 90dc9d98 megaraid_sas : MFI MPT linked list corruption fix
because changes done in part 1 has fixed the problem of MFI MPT linked list
corruption. part 2 is very much dependent on part 1, so we decided to have
single patch for these two logical changes.

[jejb: remove chatty printk pointed out by hch]
Signed-off-by: NKashyap Desai <kashyap.desai@avagotech.com>
Signed-off-by: NSumit Saxena <sumit.saxena@avagotech.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJames Bottomley <JBottomley@Odin.com>

Signed-off-by: NKashyap Desai <kashyap.desai@avagotech.com>
Signed-off-by: NSumit Saxena <sumit.saxena@avagotech.com>
Reviewed-by: NHannes Reinecke <hare@suse.de>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJames Bottomley <JBottomley@Odin.com>

Signed-off-by: NKashyap Desai <kashyap.desai@avagotech.com>
Signed-off-by: NSumit Saxena <sumit.saxena@avagotech.com>
Reviewed-by: NTomas Henzl <thenzl@redhat.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJames Bottomley <JBottomley@Odin.com>

Update megaraid_sas driver version.
Signed-off-by: NSumit Saxena <sumit.saxena@avagotech.com>
Reviewed-by: NMartin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

1) For fusion adapters, limit reserved frames for non SCSI commands to 8
   (3 for parallel IOCTLs + 5 for driver's internal DCMDs).
   Earlier reserved commands for non SCSI IO frames was set to 32, so with
   this implementation, increased per controller "can_queue".
   Behavior of MFI controllers will remain unchanged.

2) Optimize the code related to per controller's 'can_queue' setting.
Signed-off-by: NSumit Saxena <sumit.saxena@avagotech.com>
Signed-off-by: NChaitra Basappa <chaitra.basappa@avagotech.com>
Reviewed-by: NMartin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

This patch adds support for Secure Encrypting Drives (SED) in JBOD mode:

1) If the firmware supports SED JBOD, all non read/write commands to JBODs
   will be sent via firmware path, and read/write commands to JBODs will
   be sent via fastpath.
2) If the firmware does not support SED JBOD, driver will fall back to the
   old design, i.e. send all JBOD I/O via fastpath.
Signed-off-by: NSumit Saxena <sumit.saxena@avagotech.com>
Signed-off-by: NChaitra Basappa <chaitra.basappa@avagotech.com>
Reviewed-by: NMartin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

In OCR (Online Controller Reset) path, driver sets adapter state to
MEGASAS_HBA_OPERATIONAL before getting new RAID map.  There will be a small
window where IO will come from OS with old RAID map.  This patch will
update adapter state to MEGASAS_HBA_OPERATIONAL, only after driver has new
RAID map to avoid any IOs getting build using old RAID map.
Signed-off-by: NSumit Saxena <sumit.saxena@avagotech.com>
Signed-off-by: NKashyap Desai <kashyap.desai@avagotech.com>
Reviewed-by: NTomas Henzl <thenzl@redhat.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

Update MAINTAINERS list and copyright information for megaraid_sas driver.
Signed-off-by: NSumit Saxena <sumit.saxena@avagotech.com>
Reviewed-by: NTomas Henzl <thenzl@redhat.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

Update driver version and remove some meta data (release date and extended
version) about megaraid_sas driver.
Signed-off-by: NSumit Saxena <sumit.saxena@avagotech.com>
Reviewed-by: NTomas Henzl <thenzl@redhat.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

Resending the patch. Addressed the review comments by Tomas Henzl.

Driver version upgrade patch.
Signed-off-by: NSumit Saxena <sumit.saxena@avagotech.com>
Signed-off-by: NKashyap Desai <kashyap.desai@avagotech.com>
Reviewed-by: NTomas Henzl <thenzl@redhat.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

Resending the patch. Addressed the review comments from Tomas Henzl.
Added comment for to-do work.

Problem statement:
MFI link list in megaraid_sas driver is used from mfi-mpt pass-through commands.
This list can be corrupted due to many possible race conditions in driver and
eventually we may see kernel panic.

One example -
MFI frame is freed from calling process as driver send command via polling method and interrupt
for that command comes after driver free mfi frame (actually even after some other context reuse
the mfi frame). When driver receive MPT frame in ISR, driver will be using the index of MFI and
access that MFI frame and finally in-used MFI frame’s list will be corrupted.

High level description of new solution -
Free MFI and MPT command from same context.
Free both the command either from process (from where mfi-mpt pass-through was called) or from
ISR context. Do not split freeing of MFI and MPT, because it creates the race condition which
will do MFI/MPT list corruption.

Renamed the cmd_pool_lock which is used in instance as well as fusion with below name.
mfi_pool_lock and mpt_pool_lock to add more code readability.
Signed-off-by: NSumit Saxena <sumit.saxena@avagotech.com>
Signed-off-by: NKashyap Desai <kashyap.desai@avagotech.com>
Reviewed-by: NTomas Henzl <thenzl@redhat.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

Resending the patch. Addressed the review comments from Tomas Henzl.

Current driver does fast path read load balancing between arm and mirror disk
for two Drive Raid-1 configuration only.

Now, Driver support fast path read load balancing for all (any number of disk) Raid-1 configuration.
Signed-off-by: NSumit Saxena <sumit.saxena@avagotech.com>
Signed-off-by: NKashyap Desai <kashyap.desai@avagotech.com>
Reviewed-by: NTomas Henzl <thenzl@redhat.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

Resending the patch. Addressed the review comments from Tomas Henzl.
reserved1 field(part of union) of Raid map struct was not required so it is removed.

Current MegaRAID firmware and hence the driver only supported 64VDs.
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.
So with this changes, driver can also work in host lock less mode. Please
see next patch which enable host lock less mode for megaraid_sas driver.
Signed-off-by: NSumit Saxena <sumit.saxena@avagotech.com>
Signed-off-by: NKashyap Desai <kashyap.desai@avagotech.com>
Reviewed-by: NTomas Henzl <thenzl@redhat.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

Resending the patch. Addressed the review comments from Tomas Henzl.
Move buff_offset inside spinlock, corrected loop at crash dump buffer free,
reset_devices check is added to disable fw crash dump feature in kdump kernel.

This feature will provide similar interface as kernel crash dump feature.
When megaraid firmware encounter any crash, driver will collect the firmware raw image and
dump it into pre-configured location.

Driver will allocate two different segment of memory.
#1 Non-DMA able large buffer (will be allocated on demand) to capture actual FW crash dump.
#2 DMA buffer (persistence allocation) just to do a arbitrator job.

Firmware will keep writing Crash dump data in chucks of DMA buffer size into #2,
which will be copy back by driver to the host memory as described in #1.

Driver-Firmware interface:
==================
A.) Host driver can allocate maximum 512MB Host memory to store crash dump data.

This memory will be internal to the host and will not be exposed to the Firmware.
Driver may not be able to allocate 512 MB. In that case, driver will do possible memory
(available at run time) allocation to store crash dump data.

Let’s call this buffer as Host Crash Buffer.

Host Crash buffer will not be contigious as a whole, but it will have multiple chunk of contigious memory.
This will be internal to driver and firmware/application are unaware of it.
Partial allocation of Host Crash buffer may have valid information to debug depending upon
what was collected in that buffer and depending on nature of failure.

Complete Crash dump is the best case, but we do want to capture partial buffer just to grab something rather than nothing.
Host Crash buffer will be allocated only when FW Crash dump data is available,
and will be deallocated once application copy Host Crash buffer to the file.
Host Crash buffer size can be anything between 1MB to 512MB. (It will be multiple of 1MBs)

B.) Irrespective of underlying Firmware capability of crash dump support,
driver will allocate DMA buffer at start of the day for each MR controllers.
Let’s call this buffer as “DMA Crash Buffer”.

For this feature, size of DMA crash buffer will be 1MB.
(We will not gain much even if DMA buffer size is increased.)

C.) Driver will now read Controller Info sending existing dcmd “MR_DCMD_CTRL_GET_INFO”.
Driver should extract the information from ctrl info provided by firmware and
figure out if firmware support crash dump feature or not.

Driver will enable crash dump feature only if
“Firmware support Crash dump” +
“Driver was able to create DMA Crash Buffer”.

If either one from above is not set, Crash dump feature should be disable in driver.
Firmware will enable crash dump feature only if “Driver Send DCMD- MR_DCMD_SET_CRASH_BUF_PARA with MR_CRASH_BUF_TURN_ON”

Helper application/script should use sysfs parameter fw_crash_xxx to actually copy data from
host memory to the filesystem.
Signed-off-by: NSumit Saxena <sumit.saxena@avagotech.com>
Signed-off-by: NKashyap Desai <kashyap.desai@avagotech.com>
Reviewed-by: NTomas Henzl <thenzl@redhat.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

The following patch for megaraid_sas updates the driver version and
Documentation/scsi/ChangeLog.megaraid_sas.
Signed-off-by: NAdam Radford <aradford@gmail.com>
Reviewed-by: NMartin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

The following patch for megaraid_sas removes some unused variables from the megasas_instance structure.
Signed-off-by: NAdam Radford <aradford@gmail.com>
Reviewed-by: NMartin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

The following patch for megaraid_sas fixes the LD/VF affiliation policy parsing
code to account for LD targetId's and Hidden LD's (not yet affiliated with any
Virtual Functions).  This also breaks megasas_get_ld_vf_affiliation() into 2
separate functions:  megasas_get_ld_vf_affiliation_111() and
megasas_get_ld_Vf_affiliation_12() to reduce indentation levels.
Signed-off-by: NAdam Radford <aradford@gmail.com>
Reviewed-by: NMartin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

The following patch for megaraid_sas updates the driver version to
v06.803.01.00-rc1, and updates Documentation/scsi/ChangeLog.megaraid_sas.
Signed-off-by: NAdam Radford <aradford@gmail.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

The following patch for megaraid_sas adds Dell PowerEdge VRTS SR-IOV VF
support (Device ID 0x002f).

This patch has some > 80 column lines that need to be left in place
for code readability purposes.
Signed-off-by: NAdam Radford <aradford@gmail.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

Signed-off-by: NSumit Saxena <sumit.saxena@lsi.com>
Signed-off-by: NKashyap Desai <kashyap.desai@lsi.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

The assumption that sizeof(long) >= sizeof(resource_size_t) can lead to
truncation of the PCI resource address, meaning this driver didn't work
on 32-bit systems with 64-bit PCI adressing ranges.
Signed-off-by: NBen Collins <ben.c@servergy.com>
Acked-by: NSumit Saxena <sumit.saxena@lsi.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

There is syncronization problem between sysPD IO path and AEN path. Driver
maintains instance->pd_list[] array, which will get updated(by calling
function megasas_get_pd_list[]), whenever any of below events occurs-

MR_EVT_PD_INSERTED
MR_EVT_PD_REMOVED
MR_EVT_CTRL_HOST_BUS_SCAN_REQUESTED
MR_EVT_FOREIGN_CFG_IMPORTED

At same time running sysPD IO will be accessing the same array
instance->pd_list[], which is getting updated in AEN path, because of this IO
may not get correct PD info from instance->pd_list[] array.
Signed-off-by: NAdam Radford <adam.radford@lsi.com>
Signed-off-by: NSumit Saxena <sumit.saxena@lsi.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

This patch will add big endian architecture support to megaraid_sas
driver. The support added is for LSI MegaRAID all generation controllers-
(3Gb/s, 6Gb/s and 12 Gb/s controllers).

We have done basic sanity test @ppc64 arch and @x86_64. Additional
testing/observations are welcome.

[jejb: fix up rejections]
Signed-off-by: NKashyap Desai <kashyap.desai@lsi.com>
Signed-off-by: NSumit Saxena <sumit.saxena@lsi.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

Signed-off-by: NAdam Radford <aradford@gmail.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

Signed-off-by: NAdam Radford <aradford@gmail.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

Signed-off-by: NSumit Saxena <sumit.saxena@lsi.com>
Signed-off-by: NKashyap Desai <kashyap.desai@lsi.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

Add support to differentiate between iMR(no external memory) and MR(with
external memory) controllers.
Signed-off-by: NSumit Saxena <sumit.saxena@lsi.com>
Signed-off-by: NKashyap Desai <kashyap.desai@lsi.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

MegaRAID older Firmware does not support uneven span configuration for PRL11.
E.g User wants to create 34 Driver PRL11 config, it was not possible using old
firmware, since it was not supported configuration in old firmware

Old Firmware expect even number of Drives in each span and same number of
physical drives at each span.  Considering above design, 17 Drives at Span-0
and 17 drives at span-1 was not possible.

Now, using this new feature Firmware and Driver both required changes.  New
Firmware can allow user to create 16 Drives at span-0 and 18 Drives at
span-1. This will allow user to create 34 Drives Uneven span PRL11.

RAID map is interface between Driver and FW to fetch all required
fields(attributes) for each Virtual Drives.  Since legacy RAID map consider
Even Span design, there was no place to keep Uneven span information in
existing Raid map.  Because of this limitation, for Uneven span VD, driver can
not use RAID map.

This patch address the changes required in Driver to support Uneven span PRL11
support.

1. Driver will find if Firmware has UnevenSpanSupport or not by reading
   Controller Info.
2. If Firmware has UnvenSpan PRL11 support, then Driver will inform about its
   capability of handling UnevenSpan PRL11 to the firmware.
3. Driver will update its copy of span info on each time Raid map update is
   called.
4. Follow different IO path if it is Uneven Span. (For Uneven Span, Driver
   uses Span Set info to find relavent fields for that particular Virtual
   Disk)

More verbose prints will be available by setting "SPAN_DEBUG" to 1 at
compilation time.
Signed-off-by: NSumit Saxena <sumit.saxena@lsi.com>
Signed-off-by: NKashyap Desai <kashyap.desai@lsi.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

This Driver will use more than 8 MSI-x support provided by Invader/Fury max
upto 128 MSI-x.

[jejb: fix checkpatch warning]
Signed-off-by: NSumit Saxena <sumit.saxena@lsi.com>
Signed-off-by: NKashyap Desai <kashyap.desai@lsi.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

Signed-off-by: NSumit Saxena <sumit.saxena@lsi.com>
Signed-off-by: NKashyap Desai <kashyap.desai@lsi.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

Signed-off-by: NSumit Saxena <sumit.saxena@lsi.com>
Signed-off-by: NKashyap Desai <kashyap.desai@lsi.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

Previously we used PCI_MSI_FLAGS to locate a register in the MSI-X
capability.  This did work because the MSI and MSI-X flags happen
to be at the same offsets, but was confusing.

PCI_MSIX_FLAGS_ENABLE is already defined in include/uapi/linux/pci_regs.h,
so no need to define it again.
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
Acked-by: NAdam Radford <aradford@gmail.com>

This patch updates the megaraid_sas driver version and updates
Documentation/scsi/ChangeLog.megaraid_sas.
Signed-off-by: NAdam Radford <aradford@gmail.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

megaraid use INIT_WORK to declare a hotplug_work, but cast the
hotplug_work from work_struct to delayed_work and
schedule_delayed_work on it.  This is very dangerous, as other part of
delayed_work might be kernel memories allocated by others.

With commit 8852aac2 ("workqueue: mod_delayed_work_on() shouldn't queue
timer on 0 delay"), schedule_delayed_work() will check dwork->timer
before queue_work even when @delay is 0, this causes megaraid code to
hit the BUG_ON() in workqueue code.  Change megaraid code to use
delayed work.
Signed-off-by: NXiaotian Feng <dannyfeng@tencent.com>
Signed-off-by: NTejun Heo <tj@kernel.org>
Cc: Neela Syam Kolli <megaraidlinux@lsi.com>
Cc: "James E.J. Bottomley" <JBottomley@parallels.com>
Cc: linux-scsi@vger.kernel.org

Signed-off-by: NAdam Radford <aradford@gmail.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>