Use dma_pool_zalloc() instead of dma_pool_alloc + memset
Signed-off-by: Souptick Joarder <jrdr.linux@gmail.com>
Acked-by: Manish Rangankar <Manish.Rangankar@cavium.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
This patch does not change any functionality but slightly reduces
the size of the compiled kernel module.
Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Cc: Himanshu Madhani <himanshu.madhani@cavium.com>
Acked-by: Himanshu Madhani <himanshu.madhani@cavium.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Remove a few preprocessor macros that are not used anywhere.
Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Cc: Himanshu Madhani <himanshu.madhani@cavium.com>
Acked-by: Himanshu Madhani <himanshu.madhani@cavium.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Use dma_zalloc_coherent instead of dma_alloc_coherent followed by memset
0.
Generated-by: scripts/coccinelle/api/alloc/kzalloc-simple.cocci
Suggested-by: Luis R. Rodriguez <mcgrof@kernel.org>
Signed-off-by: Himanshu Jha <himanshujha199640@gmail.com>
Acked-by: Manish Rangankar <Manish.Rangankar@cavium.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
In preparation for unconditionally passing the struct timer_list pointer to
all timer callbacks, switch to using the new timer_setup() and from_timer()
to pass the timer pointer explicitly.
Cc: QLogic-Storage-Upstream@qlogic.com
Cc: "James E.J. Bottomley" <jejb@linux.vnet.ibm.com>
Cc: "Martin K. Petersen" <martin.petersen@oracle.com>
Cc: linux-scsi@vger.kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Acked-by: Manish Rangankar <Manish.Rangankar@cavium.com>
trivial fix to spelling mistake in DEBUG2 debug message
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Acked-by: Manish Rangankar <Manish.Rangankar@cavium.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
The redundant init_completion() here seems to be a cut&past error as
struct scsi_qla_host only has 4 completion elements to initialize, thus
the duplicate init_completion(disable_acb_comp) is simply removed.
Signed-off-by: Nicholas Mc Guire <der.herr@hofr.at>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Spotted while preparing qla2xxx changes as the symbols exist in both
drivers (sigh..).
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Cao jin <caoj.fnst@cn.fujitsu.com>
Acked-by: Nilesh Javali <nilesh.javali@cavium.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
And simplify the MSI-X logic in general - just request the two vectors
directly instead of going through an indirection table.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Nilesh Javali <nilesh.javali@cavium.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
In the kernel we have nice specifier to print MAC by given pointer to
the address in a binary form.
Signed-off-by: Oleksandr Khoshaba <Oleksandr.Khoshaba@gmail.com>
Acked-by: Vikas Chaudhary <vikas.chaudhary@qlogic.com>
Cc: QLogic-Storage-Upstream@qlogic.com
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Ewan D. Milne <emilne@redhat.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
We get 1 warning when build kernel with W=1:
drivers/scsi/qla4xxx/ql4_nx.c:1846:10: warning: no previous prototype for 'ql4_84xx_ipmdio_rd_reg' [-Wmissing-prototypes]
In fact, this function is only used in the file in which it is declared
and don't need a declaration, but can be made static. This patch marks
this function with 'static'.
Signed-off-by: Baoyou Xie <baoyou.xie@linaro.org>
Acked-by: Nilesh Javali <nilesh.javali@qlogic.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
The qla4_83xx_rd_reg_indirect() function can fail when it is unable to
read a register, but not all callers check its return value before using
the register data, and gcc correctly warns about this:
qla4xxx/ql4_83xx.c: In function 'qla4_83xx_process_reset_template':
qla4xxx/ql4_83xx.c:1073:36: warning: 'value' may be used uninitialized in this function
ha->reset_tmplt.array[index++] = value;
^
qla4xxx/ql4_83xx.c:1050:11: note: 'value' was declared here
uint32_t value;
^
qla4xxx/ql4_83xx.c:902:8: warning: 'value' may be used uninitialized in this function
value &= p_rmw_hdr->test_mask;
^
qla4xxx/ql4_83xx.c:895:11: note: 'value' was declared here
uint32_t value;
^
In file included from ../include/linux/io.h:25:0,
from ../include/linux/pci.h:31,
from ../drivers/scsi/qla4xxx/ql4_def.h:16,
from ../drivers/scsi/qla4xxx/ql4_83xx.c:10:
asm/io.h:101:2: warning: 'value' may be used uninitialized in this function
asm volatile("str %1, %0"
^
qla4xxx/ql4_83xx.c:874:11: note: 'value' was declared here
uint32_t value;
^
Unfortunately, I don't see any helpful way to add proper error handling
for this case, and the failure scenario for rd_reg seems rather obscure,
so this bails out and makes the rd_reg accessor set the result to
0xffffffff so we at least get a predictable value.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Nilesh Javali <nilesh.javali@qlogic.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Sorry for the delay in this patch which was mostly caused by getting the
merger of the mpt2/mpt3sas driver, which was seen as an essential item of
maintenance work to do before the drivers diverge too much. Unfortunately,
this caused a compile failure (detected by linux-next), which then had to be
fixed up and incubated. In addition to the mpt2/3sas rework, there are
updates from pm80xx, lpfc, bnx2fc, hpsa, ipr, aacraid, megaraid_sas, storvsc
and ufs plus an assortment of changes including some year 2038 issues, a fix
for a remove before detach issue in some drivers and a couple of other minor
issues.
Signed-off-by: James Bottomley <JBottomley@Odin.com>
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Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi
Pull final round of SCSI updates from James Bottomley:
"Sorry for the delay in this patch which was mostly caused by getting
the merger of the mpt2/mpt3sas driver, which was seen as an essential
item of maintenance work to do before the drivers diverge too much.
Unfortunately, this caused a compile failure (detected by linux-next),
which then had to be fixed up and incubated.
In addition to the mpt2/3sas rework, there are updates from pm80xx,
lpfc, bnx2fc, hpsa, ipr, aacraid, megaraid_sas, storvsc and ufs plus
an assortment of changes including some year 2038 issues, a fix for a
remove before detach issue in some drivers and a couple of other minor
issues"
* tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (141 commits)
mpt3sas: fix inline markers on non inline function declarations
sd: Clear PS bit before Mode Select.
ibmvscsi: set max_lun to 32
ibmvscsi: display default value for max_id, max_lun and max_channel.
mptfusion: don't allow negative bytes in kbuf_alloc_2_sgl()
scsi: pmcraid: replace struct timeval with ktime_get_real_seconds()
mvumi: 64bit value for seconds_since1970
be2iscsi: Fix bogus WARN_ON length check
scsi_scan: don't dump trace when scsi_prep_async_scan() is called twice
mpt3sas: Bump mpt3sas driver version to 09.102.00.00
mpt3sas: Single driver module which supports both SAS 2.0 & SAS 3.0 HBAs
mpt2sas, mpt3sas: Update the driver versions
mpt3sas: setpci reset kernel oops fix
mpt3sas: Added OEM Gen2 PnP ID branding names
mpt3sas: Refcount fw_events and fix unsafe list usage
mpt3sas: Refcount sas_device objects and fix unsafe list usage
mpt3sas: sysfs attribute to report Backup Rail Monitor Status
mpt3sas: Ported WarpDrive product SSS6200 support
mpt3sas: fix for driver fails EEH, recovery from injected pci bus error
mpt3sas: Manage MSI-X vectors according to HBA device type
...
This patch changes the !blk-mq path to the same defaults as the blk-mq
I/O path by always enabling block tagging, and always using host wide
tags. We've had blk-mq available for a few releases so bugs with
this mode should have been ironed out, and this ensures we get better
coverage of over tagging setup over different configs.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Jens Axboe <axboe@kernel.dk>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: James Bottomley <JBottomley@Odin.com>
These are not implementations of default architecture code but helpers
for drivers. Move them to the place they belong to.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Darren Hart <dvhart@linux.intel.com>
Acked-by: Hitoshi Mitake <mitake.hitoshi@lab.ntt.co.jp>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Pull networking updates from David Miller:
1) Add TX fast path in mac80211, from Johannes Berg.
2) Add TSO/GRO support to ibmveth, from Thomas Falcon
3) Move away from cached routes in ipv6, just like ipv4, from Martin
KaFai Lau.
4) Lots of new rhashtable tests, from Thomas Graf.
5) Run ingress qdisc lockless, from Alexei Starovoitov.
6) Allow servers to fetch TCP packet headers for SYN packets of new
connections, for fingerprinting. From Eric Dumazet.
7) Add mode parameter to pktgen, for testing receive. From Alexei
Starovoitov.
8) Cache access optimizations via simplifications of build_skb(), from
Alexander Duyck.
9) Move page frag allocator under mm/, also from Alexander.
10) Add xmit_more support to hv_netvsc, from KY Srinivasan.
11) Add a counter guard in case we try to perform endless reclassify
loops in the packet scheduler.
12) Extern flow dissector to be programmable and use it in new "Flower"
classifier. From Jiri Pirko.
13) AF_PACKET fanout rollover fixes, performance improvements, and new
statistics. From Willem de Bruijn.
14) Add netdev driver for GENEVE tunnels, from John W Linville.
15) Add ingress netfilter hooks and filtering, from Pablo Neira Ayuso.
16) Fix handling of epoll edge triggers in TCP, from Eric Dumazet.
17) Add an ECN retry fallback for the initial TCP handshake, from Daniel
Borkmann.
18) Add tail call support to BPF, from Alexei Starovoitov.
19) Add several pktgen helper scripts, from Jesper Dangaard Brouer.
20) Add zerocopy support to AF_UNIX, from Hannes Frederic Sowa.
21) Favor even port numbers for allocation to connect() requests, and
odd port numbers for bind(0), in an effort to help avoid
ip_local_port_range exhaustion. From Eric Dumazet.
22) Add Cavium ThunderX driver, from Sunil Goutham.
23) Allow bpf programs to access skb_iif and dev->ifindex SKB metadata,
from Alexei Starovoitov.
24) Add support for T6 chips in cxgb4vf driver, from Hariprasad Shenai.
25) Double TCP Small Queues default to 256K to accomodate situations
like the XEN driver and wireless aggregation. From Wei Liu.
26) Add more entropy inputs to flow dissector, from Tom Herbert.
27) Add CDG congestion control algorithm to TCP, from Kenneth Klette
Jonassen.
28) Convert ipset over to RCU locking, from Jozsef Kadlecsik.
29) Track and act upon link status of ipv4 route nexthops, from Andy
Gospodarek.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1670 commits)
bridge: vlan: flush the dynamically learned entries on port vlan delete
bridge: multicast: add a comment to br_port_state_selection about blocking state
net: inet_diag: export IPV6_V6ONLY sockopt
stmmac: troubleshoot unexpected bits in des0 & des1
net: ipv4 sysctl option to ignore routes when nexthop link is down
net: track link-status of ipv4 nexthops
net: switchdev: ignore unsupported bridge flags
net: Cavium: Fix MAC address setting in shutdown state
drivers: net: xgene: fix for ACPI support without ACPI
ip: report the original address of ICMP messages
net/mlx5e: Prefetch skb data on RX
net/mlx5e: Pop cq outside mlx5e_get_cqe
net/mlx5e: Remove mlx5e_cq.sqrq back-pointer
net/mlx5e: Remove extra spaces
net/mlx5e: Avoid TX CQE generation if more xmit packets expected
net/mlx5e: Avoid redundant dev_kfree_skb() upon NOP completion
net/mlx5e: Remove re-assignment of wq type in mlx5e_enable_rq()
net/mlx5e: Use skb_shinfo(skb)->gso_segs rather than counting them
net/mlx5e: Static mapping of netdev priv resources to/from netdev TX queues
net/mlx4_en: Use HW counters for rx/tx bytes/packets in PF device
...
vmalloc.h used to be included from include/net/inet_hashtables.h
but it is no longer the case.
Fixes: 095dc8e0c3 ("tcp: fix/cleanup inet_ehash_locks_alloc()")
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Eric Dumazet <edumzet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Drop the now unused reason argument from the ->change_queue_depth method.
Also add a return value to scsi_adjust_queue_depth, and rename it to
scsi_change_queue_depth now that it can be used as the default
->change_queue_depth implementation.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Mike Christie <michaelc@cs.wisc.edu>
Reviewed-by: Hannes Reinecke <hare@suse.de>
All drivers use the implementation for ramping the queue up and down, so
instead of overloading the change_queue_depth method call the
implementation diretly if the driver opts into it by setting the
track_queue_depth flag in the host template.
Note that a few drivers validated the new queue depth in their
change_queue_depth method, but as we never go over the queue depth
set during slave_configure or the sysfs file this isn't nessecary
and can safely be removed.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Mike Christie <michaelc@cs.wisc.edu>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Venkatesh Srinivas <venkateshs@google.com>
Now that we also get proper values in cmd->request->tag for untagged
commands, there is no need to force tagged_supported to on in drivers
that need host-wide tags.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Mike Christie <michaelc@cs.wisc.edu>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Remove the tagged argument from scsi_adjust_queue_depth, and just let it
handle the queue depth. For most drivers those two are fairly separate,
given that most modern drivers don't care about the SCSI "tagged" status
of a command at all, and many old drivers allow queuing of multiple
untagged commands in the driver.
Instead we start out with the ->simple_tags flag set before calling
->slave_configure, which is how all drivers actually looking at
->simple_tags except for one worke anyway. The one other case looks
broken, but I've kept the behavior as-is for now.
Except for that we only change ->simple_tags from the ->change_queue_type,
and when rejecting a tag message in a single driver, so keeping this
churn out of scsi_adjust_queue_depth is a clear win.
Now that the usage of scsi_adjust_queue_depth is more obvious we can
also remove all the trivial instances in ->slave_alloc or ->slave_configure
that just set it to the cmd_per_lun default.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Mike Christie <michaelc@cs.wisc.edu>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Allow a driver to ask for block layer tags by setting .use_blk_tags in the
host template, in which case it will always see a valid value in
request->tag, similar to the behavior when using blk-mq. This means even
SCSI "untagged" commands will now have a tag, which is especially useful
when using a host-wide tag map.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Mike Christie <michaelc@cs.wisc.edu>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Unless we want to build a SPI tag message we should just check SCMD_TAGGED
instead of reverse engineering a tag type through the use of
scsi_populate_tag_msg.
Also rename the function to spi_populate_tag_msg, make it behave like the
other spi message helpers, and move it to the spi transport class.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Mike Christie <michaelc@cs.wisc.edu>
Reviewed-by: Hannes Reinecke <hare@suse.de>
qla4xxx was not always returning -EXYZ error codes when
qla4xxx_get_host_stats failed.
Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Acked-by: Vikas Chaudhary <vikas.chaudhary@qlogic.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
the qla4xxx_alloc_fw_dump() calls dma_alloc_coherent() but does not
check its return value.
Signed-off-by: Maurizio Lombardi <mlombard@redhat.com>
Acked-By: Nilesh Javali <nilesh.javali@qlogic.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Replacing strncpy with strlcpy to avoid strings that lacks null terminate.
And in some cases modified to copy one character less than the overall
length, as the entire area is already zeroed.
Signed-off-by: Rickard Strandqvist <rickard_strandqvist@spectrumdigital.se>
Acked-By: Nilesh Javali <nilesh.javali@qlogic.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
As result of deprecation of MSI-X/MSI enablement functions
pci_enable_msix() and pci_enable_msi_block() all drivers
using these two interfaces need to be updated to use the
new pci_enable_msi_range() or pci_enable_msi_exact()
and pci_enable_msix_range() or pci_enable_msix_exact()
interfaces.
Signed-off-by: Alexander Gordeev <agordeev@redhat.com>
Acked-By: Vikas Chaudhary <vikas.chaudhary@qlogic.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
The SCSI standard defines 64-bit values for LUNs, and large arrays
employing large or hierarchical LUN numbers become more and more
common.
So update the linux SCSI stack to use 64-bit LUN numbers.
Signed-off-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Christoph Hellwig <hch@infradead.org>
Reviewed-by: Ewan Milne <emilne@redhat.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
This issue was reported by coccicheck using the semantic patch
at scripts/coccinelle/api/memdup.cocci
Signed-off-by: Benoit Taine <benoit.taine@lip6.fr>
Acked-by: Vikas Chaudhary <vikas.chaudhary@qlogic.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Fix following smatch warning:-
drivers/scsi/qla4xxx/ql4_os.c:1752 qla4xxx_get_ep_param() warn: variable dereferenced before check 'qla_ep' (see line 1745)
Signed-off-by: Vikas Chaudhary <vikas.chaudhary@qlogic.com>
Reviewed-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Issue:
modprobe qla4xxx is killed by systemd due to timeout.
Solution:
The exporting of sysfs DDBs from qla4xxx_probe_adapter added delay of
approximately 15s due to which system-udevd killed the modprobe of the
driver. Added fix to export the sysfs DDBs from the DPC handler.
Signed-off-by: Nilesh Javali <nilesh.javali@qlogic.com>
Signed-off-by: Vikas Chaudhary <vikas.chaudhary@qlogic.com>
Reviewed-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Use correct goto statement to free dma memory in case of
failure in function qla4_84xx_config_acb()
Signed-off-by: Vikas Chaudhary <vikas.chaudhary@qlogic.com>
Reviewed-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Issue:
System crash while target discovery for ISP40XX
Root cause:
Function qla4xxx_init_rings() is not called for ISP40XX
Fix:
Call function qla4xxx_init_rings() for ISP40XX from
qla4xxx_start_firmware().
Signed-off-by: Vikas Chaudhary <vikas.chaudhary@qlogic.com>
Reviewed-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Check for correct return status in function -
qla4_8xxx_minidump_pex_dma_read
Signed-off-by: Vikas Chaudhary <vikas.chaudhary@qlogic.com>
Reviewed-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Updated driver with new opcode (RDDFE, RDMDIO and POLLWR) which are
added with latest firmware minidump template
Signed-off-by: Tej Parkash <tej.parkash@qlogic.com>
Signed-off-by: Vikas Chaudhary <vikas.chaudhary@qlogic.com>
Reviewed-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Problem:
iSCSI stop_firmware mailbox command is not completing outstanding IO.
Solution:
Do not wait for IO completion after issuing stop_firmware mailbox
command
Signed-off-by: Tej Parkash <tej.parkash@qlogic.com>
Signed-off-by: Vikas Chaudhary <vikas.chaudhary@qlogic.com>
Reviewed-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Replace the session lock with two locks, a forward lock and
a backwards lock named frwd_lock and back_lock respectively.
The forward lock protects resources that change while sending a
request to the target, such as cmdsn, queued_cmdsn, and allocating
task from the commands' pool with kfifo_out.
The backward lock protects resources that change while processing
a response or in error path, such as cmdsn_exp, cmdsn_max, and
returning tasks to the commands' pool with kfifo_in.
Under a steady state fast-path situation, that is when one
or more processes/threads submit IO to an iscsi device and
a single kernel upcall (e.g softirq) is dealing with processing
of responses without errors, this patch eliminates the contention
between the queuecommand()/request response/scsi_done() flows
associated with iscsi sessions.
Between the forward and the backward locks exists a strict locking
hierarchy. The mutual exclusion zone protected by the forward lock can
enclose the mutual exclusion zone protected by the backward lock but not
vice versa.
For example, in iscsi_conn_teardown or in iscsi_xmit_data when there is
a failure and __iscsi_put_task is called, the backward lock is taken while
the forward lock is still taken. On the other hand, if in the RX path a nop
is to be sent, for example in iscsi_handle_reject or __iscsi_complete_pdu
than the forward lock is released and the backward lock is taken for the
duration of iscsi_send_nopout, later the backward lock is released and the
forward lock is retaken.
libiscsi_tcp uses two kernel fifos the r2t pool and the r2t queue.
The insertion and deletion from these queues didn't corespond to the
assumption taken by the new forward/backwards session locking paradigm.
That is, in iscsi_tcp_clenup_task which belongs to the RX (backwards)
path, r2t is taken out from r2t queue and inserted to the r2t pool.
In iscsi_tcp_get_curr_r2t which belong to the TX (forward) path, r2t
is also inserted to the r2t pool and another r2t is pulled from r2t
queue.
Only in iscsi_tcp_r2t_rsp which is called in the RX path but can requeue
to the TX path, r2t is taken from the r2t pool and inserted to the r2t
queue.
In order to cope with this situation, two spin locks were added,
pool2queue and queue2pool. The former protects extracting from the
r2t pool and inserting to the r2t queue, and the later protects the
extracing from the r2t queue and inserting to the r2t pool.
Signed-off-by: Shlomo Pongratz <shlomop@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
[minor fix up to apply cleanly and compile fix]
Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
