/* * Ultra Wide Band * Scanning management * * Copyright (C) 2005-2006 Intel Corporation * Inaky Perez-Gonzalez * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License version * 2 as published by the Free Software Foundation. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA * 02110-1301, USA. * * * * FIXME: docs * FIXME: there are issues here on how BEACON and SCAN on USB RCI deal * with each other. Currently seems that START_BEACON while * SCAN_ONLY will cancel the scan, so we need to update the * state here. Clarification request sent by email on * 10/05/2005. * 10/28/2005 No clear answer heard--maybe we'll hack the API * so that when we start beaconing, if the HC is * scanning in a mode not compatible with beaconing * we just fail. */ #include #include #include #include #include "uwb-internal.h" /** * Start/stop scanning in a radio controller * * @rc: UWB Radio Controller * @channel: Channel to scan; encodings in WUSB1.0[Table 5.12] * @type: Type of scanning to do. * @bpst_offset: value at which to start scanning (if type == * UWB_SCAN_ONLY_STARTTIME) * @returns: 0 if ok, < 0 errno code on error * * We put the command on kmalloc'ed memory as some arches cannot do * USB from the stack. The reply event is copied from an stage buffer, * so it can be in the stack. See WUSB1.0[8.6.2.4] for more details. */ int uwb_rc_scan(struct uwb_rc *rc, unsigned channel, enum uwb_scan_type type, unsigned bpst_offset) { int result; struct uwb_rc_cmd_scan *cmd; struct uwb_rc_evt_confirm reply; result = -ENOMEM; cmd = kzalloc(sizeof(*cmd), GFP_KERNEL); if (cmd == NULL) goto error_kzalloc; mutex_lock(&rc->uwb_dev.mutex); cmd->rccb.bCommandType = UWB_RC_CET_GENERAL; cmd->rccb.wCommand = cpu_to_le16(UWB_RC_CMD_SCAN); cmd->bChannelNumber = channel; cmd->bScanState = type; cmd->wStartTime = cpu_to_le16(bpst_offset); reply.rceb.bEventType = UWB_RC_CET_GENERAL; reply.rceb.wEvent = UWB_RC_CMD_SCAN; result = uwb_rc_cmd(rc, "SCAN", &cmd->rccb, sizeof(*cmd), &reply.rceb, sizeof(reply)); if (result < 0) goto error_cmd; if (reply.bResultCode != UWB_RC_RES_SUCCESS) { dev_err(&rc->uwb_dev.dev, "SCAN: command execution failed: %s (%d)\n", uwb_rc_strerror(reply.bResultCode), reply.bResultCode); result = -EIO; goto error_cmd; } rc->scanning = channel; rc->scan_type = type; error_cmd: mutex_unlock(&rc->uwb_dev.mutex); kfree(cmd); error_kzalloc: return result; } /* * Print scanning state */ static ssize_t uwb_rc_scan_show(struct device *dev, struct device_attribute *attr, char *buf) { struct uwb_dev *uwb_dev = to_uwb_dev(dev); struct uwb_rc *rc = uwb_dev->rc; ssize_t result; mutex_lock(&rc->uwb_dev.mutex); result = sprintf(buf, "%d %d\n", rc->scanning, rc->scan_type); mutex_unlock(&rc->uwb_dev.mutex); return result; } /* * */ static ssize_t uwb_rc_scan_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t size) { struct uwb_dev *uwb_dev = to_uwb_dev(dev); struct uwb_rc *rc = uwb_dev->rc; unsigned channel; unsigned type; unsigned bpst_offset = 0; ssize_t result = -EINVAL; result = sscanf(buf, "%u %u %u\n", &channel, &type, &bpst_offset); if (result >= 2 && type < UWB_SCAN_TOP) result = uwb_rc_scan(rc, channel, type, bpst_offset); return result < 0 ? result : size; } /** Radio Control sysfs interface (declaration) */ DEVICE_ATTR(scan, S_IRUGO | S_IWUSR, uwb_rc_scan_show, uwb_rc_scan_store); ctrl'>
authorDavid S. Miller <davem@davemloft.net>2017-01-30 14:28:22 -0800
committerDavid S. Miller <davem@davemloft.net>2017-01-30 14:28:22 -0800
commit54791b276b4000b307339f269d3bf7db877d536f (patch)
tree1c2616bd373ce5ea28aac2a53e32f5b5834901ce /fs/xfs
parent5d0e7705774dd412a465896d08d59a81a345c1e4 (diff)
parent047487241ff59374fded8c477f21453681f5995c (diff)
Merge branch 'sparc64-non-resumable-user-error-recovery'
Liam R. Howlett says: ==================== sparc64: Recover from userspace non-resumable PIO & MEM errors A non-resumable error from userspace is able to cause a kernel panic or trap loop due to the setup and handling of the queued traps once in the kernel. This patch series addresses both of these issues. The queues are fixed by simply zeroing the memory before use. PIO errors from userspace will result in a SIGBUS being sent to the user process. The MEM errors form userspace will result in a SIGKILL and also cause the offending pages to be claimed so they are no longer used in future tasks. SIGKILL is used to ensure that the process does not try to coredump and result in an attempt to read the memory again from within kernel space. Although there is a HV call to scrub the memory (mem_scrub), there is no easy way to guarantee that the real memory address(es) are not used by other tasks. Clearing the error with mem_scrub would zero the memory and cause the other processes to proceed with bad data. The handling of other non-resumable errors remain unchanged and will cause a panic. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'fs/xfs')