kernel.git/drivers/infiniband/ulp/srp, branch linux-3.18.y

IB/srp: Fix return value check in srp_init_module()

2014-08-14T15:57:54Z

In case of error, the function create_workqueue() returns NULL pointer not ERR_PTR(). The IS_ERR() test in the return value check should be replaced with NULL test. Signed-off-by: Wei Yongjun Acked-by: Bart Van Assche Signed-off-by: Roland Dreier

IB/srp: Fix residual handling

2014-08-01T22:21:51Z

From Documentation/scsi/scsi_mid_low_api.txt: "resid - an LLD should set this signed integer to the requested transfer length (i.e. 'request_bufflen') less the number of bytes that are actually transferred." This means that resid > 0 in case of an underrun and also that resid < 0 in case of an overrun. Modify the SRP initiator code such that it matches this requirement. Signed-off-by: Bart Van Assche Reviewed-by: Sagi Grimberg Reviewed-by: David Dillow Signed-off-by: Roland Dreier

IB/srp: Fix deadlock between host removal and multipathd

2014-08-01T22:21:51Z

If scsi_remove_host() is invoked after a SCSI device has been blocked, if the fast_io_fail_tmo or dev_loss_tmo work gets scheduled on the workqueue executing srp_remove_work() and if an I/O request is scheduled after the SCSI device had been blocked by e.g. multipathd then the following deadlock can occur: kworker/6:1 D ffff880831f3c460 0 195 2 0x00000000 Call Trace: [] schedule+0x29/0x70 [] schedule_timeout+0x10f/0x2a0 [] msleep+0x2f/0x40 [] __blk_drain_queue+0x4e/0x180 [] blk_cleanup_queue+0x225/0x230 [] __scsi_remove_device+0x62/0xe0 [scsi_mod] [] scsi_forget_host+0x6f/0x80 [scsi_mod] [] scsi_remove_host+0x7a/0x130 [scsi_mod] [] srp_remove_work+0x95/0x180 [ib_srp] [] process_one_work+0x1ea/0x6c0 [] worker_thread+0x11b/0x3a0 [] kthread+0xed/0x110 [] ret_from_fork+0x7c/0xb0 multipathd D ffff880096acc460 0 5340 1 0x00000000 Call Trace: [] schedule+0x29/0x70 [] schedule_timeout+0x10f/0x2a0 [] io_schedule_timeout+0x9b/0xf0 [] wait_for_completion_io_timeout+0xdc/0x110 [] blk_execute_rq+0x9b/0x100 [] sg_io+0x1a5/0x450 [] scsi_cmd_ioctl+0x2a1/0x430 [] scsi_cmd_blk_ioctl+0x42/0x50 [] sd_ioctl+0xbe/0x140 [sd_mod] [] blkdev_ioctl+0x234/0x840 [] block_ioctl+0x41/0x50 [] do_vfs_ioctl+0x300/0x520 [] SyS_ioctl+0x41/0x80 [] tracesys+0xd0/0xd5 Fix this by scheduling removal work on another workqueue than the transport layer timers. Signed-off-by: Bart Van Assche Reviewed-by: Sagi Grimberg Reviewed-by: David Dillow Cc: Sebastian Parschauer Cc: Signed-off-by: Roland Dreier

IB/srp: Avoid problems if a header uses pr_fmt

2014-05-30T04:32:54Z

SRP defines pr_fmt(fmt) to be "PFX fmt", and then includes a bunch of header files before it gets around to defining PFX. This causes problems if any of the header files do a pr_... and use pr_fmt(). Fix this by using KBUILD_MODNAME instead of the private PFX. Acked-by: Chris Metcalf Signed-off-by: Roland Dreier

IB/srp: Add fast registration support

2014-05-20T16:20:52Z

Certain HCA types (e.g. Connect-IB) and certain configurations (e.g. ConnectX VF) support fast registration but not FMR. Hence add fast registration support. In function srp_rport_reconnect(), move the the srp_finish_req() loop from after to before the srp_create_target_ib() call. This is needed to avoid that srp_finish_req() tries to queue any invalidation requests for rkeys associated with the old queue pair on the newly allocated queue pair. Invoking srp_finish_req() before the queue pair has been reallocated is safe since srp_claim_req() handles completions correctly that arrive after srp_finish_req() has been invoked. Signed-off-by: Bart Van Assche Signed-off-by: Roland Dreier

IB/srp: Rename FMR-related variables

2014-05-20T16:20:52Z

The next patch will cause the renamed variables to be shared between the code for FMR and for FR memory registration. Make the names of these variables independent of the memory registration mode. This patch does not change any functionality. The start of this patch was the changes applied via the following shell command: sed -i.orig 's/SRP_FMR_SIZE/SRP_MAX_PAGES_PER_MR/g; \ s/fmr_page_mask/mr_page_mask/g;s/fmr_page_size/mr_page_size/g; \ s/fmr_page_shift/mr_page_shift/g;s/fmr_max_size/mr_max_size/g; \ s/max_pages_per_fmr/max_pages_per_mr/g;s/nfmr/nmdesc/g; \ s/fmr_len/dma_len/g' drivers/infiniband/ulp/srp/ib_srp.[ch] Signed-off-by: Bart Van Assche Signed-off-by: Roland Dreier

IB/srp: One FMR pool per SRP connection

2014-05-20T16:20:52Z

Allocate one FMR pool per SRP connection instead of one SRP pool per HCA. This improves scalability of the SRP initiator. Only request the SCSI mid-layer to retry a SCSI command after a temporary mapping failure (-ENOMEM) but not after a permanent mapping failure. This avoids that SCSI commands are retried indefinitely if a permanent memory mapping failure occurs. Tell the SCSI mid-layer to reduce queue depth temporarily in the unlikely case where an application is queuing many requests with more than max_pages_per_fmr sg-list elements. For FMR pool allocation, base the max_pages_per_fmr parameter on the HCA memory registration limit. Only try to allocate an FMR pool if FMR is supported. Signed-off-by: Bart Van Assche Signed-off-by: Roland Dreier

IB/srp: Introduce the 'register_always' kernel module parameter

2014-05-20T16:20:52Z

Add a kernel module parameter that enables memory registration also for SG-lists that can be processed without memory registration. This makes it easier for kernel developers to test the memory registration code. Signed-off-by: Bart Van Assche Reviewed-by: Sagi Grimberg Signed-off-by: Roland Dreier

IB/srp: Introduce srp_finish_mapping()

2014-05-20T16:20:52Z

This patch does not change any functionality. Signed-off-by: Bart Van Assche Reviewed-by: Sagi Grimberg Signed-off-by: Roland Dreier

IB/srp: Introduce srp_map_fmr()

2014-05-20T16:20:51Z

This patch does not change any functionality. Signed-off-by: Bart Van Assche Reviewed-by: Sagi Grimberg Signed-off-by: Roland Dreier