/****************************************************************************** ******************************************************************************* ** ** Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved. ** Copyright (C) 2004-2008 Red Hat, Inc. All rights reserved. ** ** This copyrighted material is made available to anyone wishing to use, ** modify, copy, or redistribute it subject to the terms and conditions ** of the GNU General Public License v.2. ** ******************************************************************************* ******************************************************************************/ /* * midcomms.c * * This is the appallingly named "mid-level" comms layer. * * Its purpose is to take packets from the "real" comms layer, * split them up into packets and pass them to the interested * part of the locking mechanism. * * It also takes messages from the locking layer, formats them * into packets and sends them to the comms layer. */ #include "dlm_internal.h" #include "lowcomms.h" #include "config.h" #include "lock.h" #include "midcomms.h" static void copy_from_cb(void *dst, const void *base, unsigned offset, unsigned len, unsigned limit) { unsigned copy = len; if ((copy + offset) > limit) copy = limit - offset; memcpy(dst, base + offset, copy); len -= copy; if (len) memcpy(dst + copy, base, len); } /* * Called from the low-level comms layer to process a buffer of * commands. * * Only complete messages are processed here, any "spare" bytes from * the end of a buffer are saved and tacked onto the front of the next * message that comes in. I doubt this will happen very often but we * need to be able to cope with it and I don't want the task to be waiting * for packets to come in when there is useful work to be done. */ int dlm_process_incoming_buffer(int nodeid, const void *base, unsigned offset, unsigned len, unsigned limit) { union { unsigned char __buf[DLM_INBUF_LEN]; /* this is to force proper alignment on some arches */ union dlm_packet p; } __tmp; union dlm_packet *p = &__tmp.p; int ret = 0; int err = 0; uint16_t msglen; uint32_t lockspace; while (len > sizeof(struct dlm_header)) { /* Copy just the header to check the total length. The message may wrap around the end of the buffer back to the start, so we need to use a temp buffer and copy_from_cb. */ copy_from_cb(p, base, offset, sizeof(struct dlm_header), limit); msglen = le16_to_cpu(p->header.h_length); lockspace = p->header.h_lockspace; err = -EINVAL; if (msglen < sizeof(struct dlm_header)) break; if (p->header.h_cmd == DLM_MSG) { if (msglen < sizeof(struct dlm_message)) break; } else { if (msglen < sizeof(struct dlm_rcom)) break; } err = -E2BIG; if (msglen > dlm_config.ci_buffer_size) { log_print("message size %d from %d too big, buf len %d", msglen, nodeid, len); break; } err = 0; /* If only part of the full message is contained in this buffer, then do nothing and wait for lowcomms to call us again later with more data. We return 0 meaning we've consumed none of the input buffer. */ if (msglen > len) break; /* Allocate a larger temp buffer if the full message won't fit in the buffer on the stack (which should work for most ordinary messages). */ if (msglen > sizeof(__tmp) && p == &__tmp.p) { p = kmalloc(dlm_config.ci_buffer_size, GFP_NOFS); if (p == NULL) return ret; } copy_from_cb(p, base, offset, msglen, limit); BUG_ON(lockspace != p->header.h_lockspace); ret += msglen; offset += msglen; offset &= (limit - 1); len -= msglen; dlm_receive_buffer(p, nodeid); } if (p != &__tmp.p) kfree(p); return err ? err : ret; } >
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authorBjorn Helgaas <bhelgaas@google.com>2017-01-27 15:00:45 -0600
committerBjorn Helgaas <bhelgaas@google.com>2017-01-27 15:00:45 -0600
commit030305d69fc6963c16003f50d7e8d74b02d0a143 (patch)
tree363a4e34d199178769b7e7eeb26ea2620a55847b /include/dt-bindings/clock/r8a7796-cpg-mssr.h
parent4d191b1b63c209e37bf27938ef365244d3c41084 (diff)
PCI/ASPM: Handle PCI-to-PCIe bridges as roots of PCIe hierarchies
In a struct pcie_link_state, link->root points to the pcie_link_state of the root of the PCIe hierarchy. For the topmost link, this points to itself (link->root = link). For others, we copy the pointer from the parent (link->root = link->parent->root). Previously we recognized that Root Ports originated PCIe hierarchies, but we treated PCI/PCI-X to PCIe Bridges as being in the middle of the hierarchy, and when we tried to copy the pointer from link->parent->root, there was no parent, and we dereferenced a NULL pointer: BUG: unable to handle kernel NULL pointer dereference at 0000000000000090 IP: [<ffffffff9e424350>] pcie_aspm_init_link_state+0x170/0x820 Recognize that PCI/PCI-X to PCIe Bridges originate PCIe hierarchies just like Root Ports do, so link->root for these devices should also point to itself. Fixes: 51ebfc92b72b ("PCI: Enumerate switches below PCI-to-PCIe bridges") Link: https://bugzilla.kernel.org/show_bug.cgi?id=193411 Link: https://bugzilla.opensuse.org/show_bug.cgi?id=1022181 Tested-by: lists@ssl-mail.com Tested-by: Jayachandran C. <jnair@caviumnetworks.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> CC: stable@vger.kernel.org # v4.2+
Diffstat (limited to 'include/dt-bindings/clock/r8a7796-cpg-mssr.h')