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path: root/drivers/scsi/iscsi_tcp.c
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2006-06-05[SCSI] iscsi: update version to 1.0-595Mike Christie
Signed-off-by: Mike Christie <michaelc@cs.wisc.edu> Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2006-06-05[SCSI] iscsi: fix writepsace raceMike Christie
We can race and misset the suspend bit if iscsi_write_space is called then iscsi_send returns with a failure indicating there is no space. To handle this this patch returns a error upwards allowing xmitworker to decide if we need to try and transmit again. For the no write space case xmitworker will not retry, and instead let iscsi_write_space queue it back up if needed (this relies on the work queue code to properly requeue us if needed). Signed-off-by: Mike Christie <michaelc@cs.wisc.edu> Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2006-06-05[SCSI] iscsi: don't switch states when just cleaning upMike Christie
If recovery failed or we are in recovery only overwrite the state if we are going to terminate the session or if we logged back in. STOP_CONN_SUSPEND and conn_cnt are not used. We only support a single connection session ATM, so cleanup that code while we are working around it. Signed-off-by: Mike Christie <michaelc@cs.wisc.edu> Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2006-05-20[SCSI] iscsi: update versionMike Christie
update version Signed-off-by: Mike Christie <michaelc@cs.wisc.edu> Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2006-05-20[SCSI] iscsi: kill dtask mempoolsMike Christie
Discovered by steven@hayter.me.uk and patch by michaelc@cs.wisc.edu The dtask mempool is reserving 261120 items per session! Since we are now sending headers with sendmsg there is no reason for the mempool and that was causing us to us carzy amounts of mem. We can preallicate a header in the r2t and task struct and reuse them Signed-off-by: Mike Christie <michaelc@cs.wisc.edu> Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2006-05-20[SCSI] iscsi: dont use sendpage for iscsi headersMike Christie
From Zhen and ported by Mike: Don't use sendpage for the headers. sendpage for the pdu headers does not seem to have a performance impact, makes life harder for mutiple data pdus to be in flight and still trips up some network cards when it is from slab mem. Signed-off-by: Mike Christie <michaelc@cs.wisc.edu> Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2006-05-10[SCSI] iscsi: dequeue all buffers from queueMike Christie
debugged by wrwhitehead@novell.com patch and analysis by fujita.tomonori@lab.ntt.co.jp Only tcp_read_sock and recv_actor (iscsi_tcp_data_recv for us) see desc.count. It is is used just for permitting tcp_read_sock to read the portion of data in the socket. When iscsi_tcp_data_recv sees a partial header, it sets desc.count. However, it is possible that the next skb (containing the rest of the header) still does not come. So I'm not sure that this scheme is completely correct. Ideally, we should use the exact length of the data in the socket for desc.count. However, it is not so simple (see SIOCINQ in tcp_ioctl). So I think that iscsi_tcp_data_recv can just stop playing with desc.count and tell tcp_read_sock to read the all skbs. As proposed already, if iscsi_tcp_data_ready sets desc.count to non-zero, tcp_read_sock does that. Signed-off-by: Mike Christie <michaelc@cs.wisc.edu> Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2006-05-10[SCSI] iscsi: increment expstatsn during loginMike Christie
debugged by Ming and Rohan: The problem Ming and Rohan debugged was that during a normal session login, open-iscsi is not incrementing the exp_statsn counter. It was stuck at zero. From the RFC, it looks like if the login response PDU has a successful status then we should be incrementing that value. Also from the RFC, it looks like if when we drop a connection then reconnect, we should be using the exp_statsn from the old connection in the next relogin attempt. Signed-off-by: Mike Christie <michaelc@cs.wisc.edu> Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2006-05-10[SCSI] iscsi: align printksOr Gerlitz
align printk output Signed-off-by: Or Gerlitz <ogerlitz@voltaire.com> Signed-off-by: Mike Christie <michaelc@cs.wisc.edu> Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2006-05-10[SCSI] iscsi: add transport end point callbacksOr Gerlitz
add transport end point callbacks so iscsi drivers that cannot connect from userspace, like iscsi tcp, using sockets do not have to implement their own socket infrastructure. Signed-off-by: Or Gerlitz <ogerlitz@voltaire.com> Signed-off-by: Mike Christie <michaelc@cs.wisc.edu> Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2006-04-14[SCSI] iscsi: convert iscsi tcp to libiscsiMike Christie
This just converts iscsi_tcp to the lib Signed-off-by: Mike Christie <michaelc@cs.wisc.edu> Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2006-04-14[SCSI] iscsi: fix up iscsi ehMike Christie
The current iscsi_tcp eh is not nicely setup for dm-multipath and performs some extra task management functions when they are not needed. The attached patch: - Fixes the TMF issues. If a session is rebuilt then we do not send aborts. - Fixes the problem where if the host reset fired, we would return SUCCESS even though we had not really done anything yet. This ends up causing problem with scsi_error.c's TUR. - If someone has turned on the userspace nop daemon code to try and detect network problems before the scsi command timeout we can now drop and clean up the session before the scsi command timesout and fires the eh speeding up the time it takes for a command to go from one patch to another. For network problems we fail the command with DID_BUS_BUSY so if failfast is set scsi_decide_disposition fails the command up to dm for it to try on another path. - And we had to add some basic iscsi session block code. Previously if we were trying to repair a session we would retrun a MLQUEUE code in the queuecommand. This worked but it was not the most efficient or pretty thing to do since it would take a while to relogin to the target. For iscsi_tcp/open-iscsi a lot of the iscsi error handler is in userspace the block code is pretty bare. We will be adding to that for qla4xxx. Signed-off-by: Mike Christie <michaelc@cs.wisc.edu> Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2006-04-14[SCSI] iscsi: add sysfs attrs for uspace sync upMike Christie
For iscsi boot when going from initramfs to the real root we need to stop the userpsace iscsi daemon. To later restart it iscsid needs to be able to rebuild itself and part of that process is matching a session running the kernel with the iscsid representation. To do this the attached patch adds several required iscsi values. If the LLD does not provide them becuase, login is done in userspace, then the transport class and userspace set ths up for the LLD. Signed-off-by: Mike Christie <michaelc@cs.wisc.edu> Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2006-04-14[SCSI] iscsi: rm kernel iscsi handles usage for session and connectionMike Christie
from hare@suse.de and michaelc@cs.wisc.edu hw iscsi like qla4xxx does not allocate a host per session and for userspace it is difficult to restart iscsid using the "iscsi handles" for the session and connection, so this patch just has the class or userspace allocate the id for the session and connection. Note: this breaks userspace and requires users to upgrade to the newest open-iscsi tools. Sorry about his but open-iscsi is still too new to say we have a stable user-kernel api and we were not good nough designers to know that other hw iscsi drivers and iscsid itself would need such changes. Actually we sorta did but at the time we did not have the HW available to us so we could only guess. Luckily, the only tools hooking into the class are the open-iscsi ones or other tools like iscsitart hook into the open-iscsi engine from userspace or prgroams like anaconda call our tools so they are not affected. Signed-off-by: Mike Christie <michaelc@cs.wisc.edu> Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2006-03-26[PATCH] mempool: use mempool_create_slab_pool()Matthew Dobson
Modify well over a dozen mempool users to call mempool_create_slab_pool() rather than calling mempool_create() with extra arguments, saving about 30 lines of code and increasing readability. Signed-off-by: Matthew Dobson <colpatch@us.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-22[PATCH] slab: Remove SLAB_NO_REAP optionChristoph Lameter
SLAB_NO_REAP is documented as an option that will cause this slab not to be reaped under memory pressure. However, that is not what happens. The only thing that SLAB_NO_REAP controls at the moment is the reclaim of the unused slab elements that were allocated in batch in cache_reap(). Cache_reap() is run every few seconds independently of memory pressure. Could we remove the whole thing? Its only used by three slabs anyways and I cannot find a reason for having this option. There is an additional problem with SLAB_NO_REAP. If set then the recovery of objects from alien caches is switched off. Objects not freed on the same node where they were initially allocated will only be reused if a certain amount of objects accumulates from one alien node (not very likely) or if the cache is explicitly shrunk. (Strangely __cache_shrink does not check for SLAB_NO_REAP) Getting rid of SLAB_NO_REAP fixes the problems with alien cache freeing. Signed-off-by: Christoph Lameter <clameter@sgi.com> Cc: Pekka Enberg <penberg@cs.helsinki.fi> Cc: Manfred Spraul <manfred@colorfullife.com> Cc: Mark Fasheh <mark.fasheh@oracle.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-04[SCSI] iscsi update: fix mgmt pool err path releaseMike Christie
>From ogerlitz@voltaire.com: mgmtpool shoild be frees in immdata_alloc_fail label. Signed-off-by: Mike Christie <michaelc@cs.wisc.edu> Signed-off-by: Alex Aizman <itn780@yahoo.com> Signed-off-by: Dmitry Yusupov <dmitry_yus@yahoo.com> Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2006-02-04[SCSI] iscsi update: set correct state at creation timeMike Christie
>From erezz@voltaire.com: We are still in ISCSI_STATE_FREE state at create time. The addition of the first connection puts us in ISCSI_STATE_LOGGED_IN. Signed-off-by: Mike Christie <michaelc@cs.wisc.edu> Signed-off-by: Alex Aizman <itn780@yahoo.com> Signed-off-by: Dmitry Yusupov <dmitry_yus@yahoo.com> Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2006-02-04[SCSI] iscsi update: rm conn lockMike Christie
>From erezz@voltaire.com: rm conn->lock since it is not used anymore. The dataqueue is protected by the session lock and xmitmutex. Signed-off-by: Mike Christie <michaelc@cs.wisc.edu> Signed-off-by: Alex Aizman <itn780@yahoo.com> Signed-off-by: Dmitry Yusupov <dmitry_yus@yahoo.com> Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2006-02-04[SCSI] iscsi update: cleanup iscsi class interfaceMike Christie
From: michaelc@cs.wisc.edu fujita.tomonori@lab.ntt.co.jp da-x@monatomic.org and err path fixup from: ogerlitz@voltaire.com This patch cleans up that interface by having the lld and class pass a iscsi_cls_session or iscsi_cls_conn between each other when the function is used by HW and SW iscsi llds. This way the lld does not have to remember if it has to send a handle or pointer and a handle or pointer to connection, session or host. This also has the class verify the session handle that gets passed from userspace instead of using the pointer passed into the kernel directly. Signed-off-by: Mike Christie <michaelc@cs.wisc.edu> Signed-off-by: Alex Aizman <itn780@yahoo.com> Signed-off-by: Dmitry Yusupov <dmitry_yus@yahoo.com> Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2006-01-14[PATCH] Unlinline a bunch of other functionsArjan van de Ven
Remove the "inline" keyword from a bunch of big functions in the kernel with the goal of shrinking it by 30kb to 40kb Signed-off-by: Arjan van de Ven <arjan@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu> Acked-by: Jeff Garzik <jgarzik@pobox.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-14[SCSI] iscsi: use pageslabMike Christie
From: FUJITA Tomonori <tomof@acm.org> and zhenyu.z.wang@intel.com: We cannot handle filesystems like XFS becuase of the pages they are sending us. We had thought page_count could be used to work around this, but the correct test is for PageSlab. The proper solution is to figure out what type of pages filesystems can use so we do not have to add tests like this or handle it in the block layer for all network block drivers but the issue still has not been resolved on fs-devel so we are sending this patch as a temporary fix. This is last patch just in case it is Nakd with the explanation that we need to push the correct fix through fs-devel, mm or the block layer. The rest of the patchset can live without the patch, but the driver will not work with filesystems like XFS. Signed-off-by: Alex Aizman <itn780@yahoo.com> Signed-off-by: Dmitry Yusupov <dmitry_yus@yahoo.com> Signed-off-by: Mike Christie <michaelc@cs.wisc.edu> Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2006-01-14[SCSI] iscsi: fix 4k stack iscsi setupsMike Christie
When we run the xmit code from queuecomand the stack trace gets too deep. The patch runs the xmit code from the scsi_host work queue. This fixes 4k stack and xfs support and should fix the st and sg stack usage bugs. Signed-off-by: Alex Aizman <itn780@yahoo.com> Signed-off-by: Dmitry Yusupov <dmitry_yus@yahoo.com> Signed-off-by: Mike Christie <michaelc@cs.wisc.edu> Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2006-01-14[SCSI] iscsi: seperate iscsi interface from setup functionsMike Christie
This is the second version of the patch to address Christoph's comments. Instead of doing the lib, I just kept everything in scsi_trnapsort_iscsi.c like the FC and SPI class. This was becuase the driver model and sysfs class is tied to the session and connection setup so separating did not buy very much at this time. The reason for this patch was becuase HW iscsi LLDs like qla4xxx cannot use the iscsi class becuase the scsi_host was tied to the interface and class code. This patch just seperates the session from scsi host so that LLDs that allocate the host per some resource like pci device can still use the class. This is also fixes a couple refcount bugs that can be triggered when users have a sysfs file open, close the session, then read or write to the file. Signed-off-by: Alex Aizman <itn780@yahoo.com> Signed-off-by: Dmitry Yusupov <dmitry_yus@yahoo.com> Signed-off-by: Mike Christie <michaelc@cs.wisc.edu> Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2006-01-14[SCSI] iscsi: add high mem supportMike Christie
From Mike Christie <michaelc@cs.wisc.edu> and FUJITA Tomonori <tomof@acm.org>: We cannot use page_address becuase some pages could be highmem. Instead, we can use sock_no_sendpage which does kmap for us. Signed-off-by: Alex Aizman <itn780@yahoo.com> Signed-off-by: Dmitry Yusupov <dmitry_yus@yahoo.com> Signed-off-by: Mike Christie <michaelc@cs.wisc.edu> Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2006-01-14[SCSI] iscsi: data digest page cache usage fixFUJITA Tomonori
Users can write to a page while we are sending it and making digest calculations. This ends up causing us to retry the command when a digest error is later reported. By using sock_no_sendpage when data digests are calculated we can avoid a lot of (not all but it helps) the retries becuase sock_no_sendpage is not zero copy. Signed-off-by: Alex Aizman <itn780@yahoo.com> Signed-off-by: Dmitry Yusupov <dmitry_yus@yahoo.com> Signed-off-by: Mike Christie <michaelc@cs.wisc.edu> Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2006-01-14[SCSI] iscsi: host locking fixzhenyu.z.wang@intel.com
We should be taking the host_lock instead of the conn lock when checking host_busy. Signed-off-by: Alex Aizman <itn780@yahoo.com> Signed-off-by: Dmitry Yusupov <dmitry_yus@yahoo.com> Signed-off-by: Mike Christie <michaelc@cs.wisc.edu> Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2006-01-14[SCSI] iscsi: data under/over flow fixzhenyu.z.wang@intel.com
We need to check the ISCSI_FLAG_DATA_* flags. Signed-off-by: Alex Aizman <itn780@yahoo.com> Signed-off-by: Dmitry Yusupov <dmitry_yus@yahoo.com> Signed-off-by: Mike Christie <michaelc@cs.wisc.edu> Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2006-01-14[SCSI] iscsi: whitespace cleanupFUJITA Tomonori
Remove extra whitespaces. Signed-off-by: Alex Aizman <itn780@yahoo.com> Signed-off-by: Dmitry Yusupov <dmitry_yus@yahoo.com> Signed-off-by: Mike Christie <michaelc@cs.wisc.edu> Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2006-01-12[SCSI] turn most scsi semaphores into mutexesArjan van de Ven
the scsi layer is using semaphores in a mutex way, this patch converts these into using mutexes instead Signed-off-by: Arjan van de Ven <arjan@infradead.org> Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2005-12-15Merge by hand (conflicts in scsi_lib.c)James Bottomley
This merge is pretty extensive. The conflict is over the new req->retries parameter, so I had to change the prototype to scsi_setup_blk_pc_cmnd() and the usage in sd, sr and st. Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2005-12-15[PATCH] iscsi gfp_t annotationsAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-12-13[SCSI] iscsi: check header digests for mgmt tasksMike Christie
From Wang Zhenyu: check header digest for cmd and mgmt tasks Signed-off-by: Wang Zhenyu <zhenyu.z.wang@intel.com> Signed-off-by: Mike Christie <michaelc@cs.wisc.edu> Signed-off-by: Alex Aizman <itn780@yahoo.com> Signed-off-by: Dmitry Yusupov <dmitry_yus@yahoo.com> Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2005-12-13[SCSI] iscsi: update versionMike Christie
Signed-off-by: Mike Christie <michaelc@cs.wisc.edu> Signed-off-by: Alex Aizman <itn780@yahoo.com> Signed-off-by: Dmitry Yusupov <dmitry_yus@yahoo.com> Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2005-12-13[SCSI] iscsi: lower queue depthMike Christie
From Wang Zhenyu: High queue depth was a problem for some targets so make queue_depth adjustable From Mike Christie Make default queue_depth a little lower Signed-off-by: Mike Christie <michaelc@cs.wisc.edu> Signed-off-by: Alex Aizman <itn780@yahoo.com> Signed-off-by: Dmitry Yusupov <dmitry_yus@yahoo.com> Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2005-12-13[SCSI] iscsi: data digest calculation fixMike Christie
From Wang Zhenyu: data digest fix (the bug caused data corruption w/Wasabi StorageBuilder target) Signed-off-by: Mike Christie <michaelc@cs.wisc.edu> Signed-off-by: Alex Aizman <itn780@yahoo.com> Signed-off-by: Dmitry Yusupov <dmitry_yus@yahoo.com> Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2005-12-13[SCSI] iscsi: iscsi response fixMike Christie
from Wang Zhenyu: Must check SCSI CMD and R2T response according to the spec Signed-off-by: Mike Christie <michaelc@cs.wisc.edu> Signed-off-by: Alex Aizman <itn780@yahoo.com> Signed-off-by: Dmitry Yusupov <dmitry_yus@yahoo.com> Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2005-12-13[SCSI] iscsi: redirect fixMike Christie
From tomof@acm.org: There is one more issue about Equallogic systems. They send re-direction info with FIN. I think that the kernel module needs to let iscsid to read data from the socket before killing it. Signed-off-by: Mike Christie <michaelc@cs.wisc.edu> Signed-off-by: Alex Aizman <itn780@yahoo.com> Signed-off-by: Dmitry Yusupov <dmitry_yus@yahoo.com> Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2005-12-13[SCSI] iscsi: opcode check fixMike Christie
Must check only valid opcode bits. Signed-off-by: Mike Christie <michaelc@cs.wisc.edu> Signed-off-by: Alex Aizman <itn780@yahoo.com> Signed-off-by: Dmitry Yusupov <dmitry_yus@yahoo.com> Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2005-09-20[SCSI] iscsi: add module versionMike Christie
From: michaelc@cs.wisc.edu I have a bad memory. I cannot remember what versions are which, so add a module version to help. Signed-off-by: Alex Aizman <itn780@yahoo.com> Signed-off-by: Dmitry Yusupov <dmitry_yus@yahoo.com> Signed-off-by: Mike Christie <michaelc@cs.wisc.edu> Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2005-09-20[SCSI] iscsi: fix nop-in handlingMike Christie
From: zhenyu.z.wang@intel.com This add check to NOOP_IN's ttt, when it's ~0UL we should not send NOOP_OUT by spec (plus some cleanup). Signed-off-by: Alex Aizman <itn780@yahoo.com> Signed-off-by: Dmitry Yusupov <dmitry_yus@yahoo.com> Signed-off-by: Mike Christie <michaelc@cs.wisc.edu> Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2005-09-20[SCSI] iscsi: fix ahs lenMike Christie
From: tomof@acm.org Fix AHS Length Signed-off-by: Alex Aizman <itn780@yahoo.com> Signed-off-by: Dmitry Yusupov <dmitry_yus@yahoo.com> Signed-off-by: Mike Christie <michaelc@cs.wisc.edu> Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2005-09-20[SCSI] iscsi: update some iscsi proto defsMike Christie
From: michaelc@cs.wisc.edu Cleanup some iscsi_proto defs, add some missing values, and fix some defs. Signed-off-by: Alex Aizman <itn780@yahoo.com> Signed-off-by: Dmitry Yusupov <dmitry_yus@yahoo.com> Signed-off-by: Mike Christie <michaelc@cs.wisc.edu> Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2005-09-20[SCSI] iscsi: handle nonlinear skbsMike Christie
From: zhenyu.z.wang@intel.com Fix oops from nonlinear skb usage. Signed-off-by: Alex Aizman <itn780@yahoo.com> Signed-off-by: Dmitry Yusupov <dmitry_yus@yahoo.com> Signed-off-by: Mike Christie <michaelc@cs.wisc.edu> Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2005-09-20[SCSI] iscsi: preemt fix and cleanupMike Christie
From: zhenyu.z.wang@intel.com Delay the head digest update until xmit time, like data digest update. [To make things cleaner and avoid prempt bug] Signed-off-by: Alex Aizman <itn780@yahoo.com> Signed-off-by: Dmitry Yusupov <dmitry_yus@yahoo.com> Signed-off-by: Mike Christie <michaelc@cs.wisc.edu> Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2005-09-20[SCSI] iscsi: nodelay fixMike Christie
From: tomof@acm.org I'm not sure about this. I don't think that NODELAY option hurts performance. However, open-iscsi does not use MSG_MORE properly with sendpage, so NODELAY option hurts the open-iscsi performance. I've attached a patch to fix NODELAY and MSG_MORE problems and the write performance results with disktest. I use Opteron boxes connected directly, Chelsio NICs, 1500-byte MTU, 64 KB I/O size, and the iSCSI parameters on open-iscsi web site. With only NODELAY fix, the performance drops, as you said. On the other hand, NODELAY and MSG_MORE fixes improve the performance overall. Signed-off-by: Alex Aizman <itn780@yahoo.com> Signed-off-by: Dmitry Yusupov <dmitry_yus@yahoo.com> Signed-off-by: Mike Christie <michaelc@cs.wisc.edu> Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2005-08-06[SCSI] open-iscsi/linux-iscsi-5 Initiator: Initiator codeAlex Aizman
drivers/scsi/iscsi_tcp.c, iscsi data path. Signed-off-by: Alex Aizman <itn780@yahoo.com> Signed-off-by: Dmitry Yusupov <dmitry_yus@yahoo.com> Signed-off-by: Mike Christie <michaelc@cs.wisc.edu> Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>