/* * Copyright (c) 2006 Oracle. All rights reserved. * * This software is available to you under a choice of one of two * licenses. You may choose to be licensed under the terms of the GNU * General Public License (GPL) Version 2, available from the file * COPYING in the main directory of this source tree, or the * OpenIB.org BSD license below: * * Redistribution and use in source and binary forms, with or * without modification, are permitted provided that the following * conditions are met: * * - Redistributions of source code must retain the above * copyright notice, this list of conditions and the following * disclaimer. * * - Redistributions in binary form must reproduce the above * copyright notice, this list of conditions and the following * disclaimer in the documentation and/or other materials * provided with the distribution. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE * SOFTWARE. * */ #include #include #include #include "ib.h" static struct ctl_table_header *rds_ib_sysctl_hdr; unsigned long rds_ib_sysctl_max_send_wr = RDS_IB_DEFAULT_SEND_WR; unsigned long rds_ib_sysctl_max_recv_wr = RDS_IB_DEFAULT_RECV_WR; unsigned long rds_ib_sysctl_max_recv_allocation = (128 * 1024 * 1024) / RDS_FRAG_SIZE; static unsigned long rds_ib_sysctl_max_wr_min = 1; /* hardware will fail CQ creation long before this */ static unsigned long rds_ib_sysctl_max_wr_max = (u32)~0; unsigned long rds_ib_sysctl_max_unsig_wrs = 16; static unsigned long rds_ib_sysctl_max_unsig_wr_min = 1; static unsigned long rds_ib_sysctl_max_unsig_wr_max = 64; /* * This sysctl does nothing. * * Backwards compatibility with RDS 3.0 wire protocol * disables initial FC credit exchange. * If it's ever possible to drop 3.0 support, * setting this to 1 and moving init/refill of send/recv * rings from ib_cm_connect_complete() back into ib_setup_qp() * will cause credits to be added before protocol negotiation. */ unsigned int rds_ib_sysctl_flow_control = 0; static struct ctl_table rds_ib_sysctl_table[] = { { .procname = "max_send_wr", .data = &rds_ib_sysctl_max_send_wr, .maxlen = sizeof(unsigned long), .mode = 0644, .proc_handler = proc_doulongvec_minmax, .extra1 = &rds_ib_sysctl_max_wr_min, .extra2 = &rds_ib_sysctl_max_wr_max, }, { .procname = "max_recv_wr", .data = &rds_ib_sysctl_max_recv_wr, .maxlen = sizeof(unsigned long), .mode = 0644, .proc_handler = proc_doulongvec_minmax, .extra1 = &rds_ib_sysctl_max_wr_min, .extra2 = &rds_ib_sysctl_max_wr_max, }, { .procname = "max_unsignaled_wr", .data = &rds_ib_sysctl_max_unsig_wrs, .maxlen = sizeof(unsigned long), .mode = 0644, .proc_handler = proc_doulongvec_minmax, .extra1 = &rds_ib_sysctl_max_unsig_wr_min, .extra2 = &rds_ib_sysctl_max_unsig_wr_max, }, { .procname = "max_recv_allocation", .data = &rds_ib_sysctl_max_recv_allocation, .maxlen = sizeof(unsigned long), .mode = 0644, .proc_handler = proc_doulongvec_minmax, }, { .procname = "flow_control", .data = &rds_ib_sysctl_flow_control, .maxlen = sizeof(rds_ib_sysctl_flow_control), .mode = 0644, .proc_handler = proc_dointvec, }, { } }; void rds_ib_sysctl_exit(void) { if (rds_ib_sysctl_hdr) unregister_net_sysctl_table(rds_ib_sysctl_hdr); } int rds_ib_sysctl_init(void) { rds_ib_sysctl_hdr = register_net_sysctl(&init_net, "net/rds/ib", rds_ib_sysctl_table); if (!rds_ib_sysctl_hdr) return -ENOMEM; return 0; } ce:mode:
authorIago Abal <mail@iagoabal.eu>2017-01-11 14:00:21 +0100
committerVinod Koul <vinod.koul@intel.com>2017-01-25 15:35:11 +0530
commit91539eb1fda2d530d3b268eef542c5414e54bf1a (patch)
tree960f5ca6342ad20837aff18aad6e8ecd7da32fd6 /net/Makefile
parent6610d0edf6dc7ee97e46ab3a538a565c79d26199 (diff)
dmaengine: pl330: fix double lock
The static bug finder EBA (http://www.iagoabal.eu/eba/) reported the following double-lock bug: Double lock: 1. spin_lock_irqsave(pch->lock, flags) at pl330_free_chan_resources:2236; 2. call to function `pl330_release_channel' immediately after; 3. call to function `dma_pl330_rqcb' in line 1753; 4. spin_lock_irqsave(pch->lock, flags) at dma_pl330_rqcb:1505. I have fixed it as suggested by Marek Szyprowski. First, I have replaced `pch->lock' with `pl330->lock' in functions `pl330_alloc_chan_resources' and `pl330_free_chan_resources'. This avoids the double-lock by acquiring a different lock than `dma_pl330_rqcb'. NOTE that, as a result, `pl330_free_chan_resources' executes `list_splice_tail_init' on `pch->work_list' under lock `pl330->lock', whereas in the rest of the code `pch->work_list' is protected by `pch->lock'. I don't know if this may cause race conditions. Similarly `pch->cyclic' is written by `pl330_alloc_chan_resources' under `pl330->lock' but read by `pl330_tx_submit' under `pch->lock'. Second, I have removed locking from `pl330_request_channel' and `pl330_release_channel' functions. Function `pl330_request_channel' is only called from `pl330_alloc_chan_resources', so the lock is already held. Function `pl330_release_channel' is called from `pl330_free_chan_resources', which already holds the lock, and from `pl330_del'. Function `pl330_del' is called in an error path of `pl330_probe' and at the end of `pl330_remove', but I assume that there cannot be concurrent accesses to the protected data at those points. Signed-off-by: Iago Abal <mail@iagoabal.eu> Reviewed-by: Marek Szyprowski <m.szyprowski@samsung.com> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Diffstat (limited to 'net/Makefile')