/* * CAIF Framing Layer. * * Copyright (C) ST-Ericsson AB 2010 * Author: Sjur Brendeland * License terms: GNU General Public License (GPL) version 2 */ #define pr_fmt(fmt) KBUILD_MODNAME ":%s(): " fmt, __func__ #include #include #include #include #include #include #include #include #define container_obj(layr) container_of(layr, struct cffrml, layer) struct cffrml { struct cflayer layer; bool dofcs; /* !< FCS active */ int __percpu *pcpu_refcnt; }; static int cffrml_receive(struct cflayer *layr, struct cfpkt *pkt); static int cffrml_transmit(struct cflayer *layr, struct cfpkt *pkt); static void cffrml_ctrlcmd(struct cflayer *layr, enum caif_ctrlcmd ctrl, int phyid); static u32 cffrml_rcv_error; static u32 cffrml_rcv_checsum_error; struct cflayer *cffrml_create(u16 phyid, bool use_fcs) { struct cffrml *this = kzalloc(sizeof(struct cffrml), GFP_ATOMIC); if (!this) return NULL; this->pcpu_refcnt = alloc_percpu(int); if (this->pcpu_refcnt == NULL) { kfree(this); return NULL; } caif_assert(offsetof(struct cffrml, layer) == 0); this->layer.receive = cffrml_receive; this->layer.transmit = cffrml_transmit; this->layer.ctrlcmd = cffrml_ctrlcmd; snprintf(this->layer.name, CAIF_LAYER_NAME_SZ, "frm%d", phyid); this->dofcs = use_fcs; this->layer.id = phyid; return (struct cflayer *) this; } void cffrml_free(struct cflayer *layer) { struct cffrml *this = container_obj(layer); free_percpu(this->pcpu_refcnt); kfree(layer); } void cffrml_set_uplayer(struct cflayer *this, struct cflayer *up) { this->up = up; } void cffrml_set_dnlayer(struct cflayer *this, struct cflayer *dn) { this->dn = dn; } static u16 cffrml_checksum(u16 chks, void *buf, u16 len) { /* FIXME: FCS should be moved to glue in order to use OS-Specific * solutions */ return crc_ccitt(chks, buf, len); } static int cffrml_receive(struct cflayer *layr, struct cfpkt *pkt) { u16 tmp; u16 len; u16 hdrchks; int pktchks; struct cffrml *this; this = container_obj(layr); cfpkt_extr_head(pkt, &tmp, 2); len = le16_to_cpu(tmp); /* Subtract for FCS on length if FCS is not used. */ if (!this->dofcs) len -= 2; if (cfpkt_setlen(pkt, len) < 0) { ++cffrml_rcv_error; pr_err("Framing length error (%d)\n", len); cfpkt_destroy(pkt); return -EPROTO; } /* * Don't do extract if FCS is false, rather do setlen - then we don't * get a cache-miss. */ if (this->dofcs) { cfpkt_extr_trail(pkt, &tmp, 2); hdrchks = le16_to_cpu(tmp); pktchks = cfpkt_iterate(pkt, cffrml_checksum, 0xffff); if (pktchks != hdrchks) { cfpkt_add_trail(pkt, &tmp, 2); ++cffrml_rcv_error; ++cffrml_rcv_checsum_error; pr_info("Frame checksum error (0x%x != 0x%x)\n", hdrchks, pktchks); return -EILSEQ; } } if (cfpkt_erroneous(pkt)) { ++cffrml_rcv_error; pr_err("Packet is erroneous!\n"); cfpkt_destroy(pkt); return -EPROTO; } if (layr->up == NULL) { pr_err("Layr up is missing!\n"); cfpkt_destroy(pkt); return -EINVAL; } return layr->up->receive(layr->up, pkt); } static int cffrml_transmit(struct cflayer *layr, struct cfpkt *pkt) { u16 chks; u16 len; __le16 data; struct cffrml *this = container_obj(layr); if (this->dofcs) { chks = cfpkt_iterate(pkt, cffrml_checksum, 0xffff); data = cpu_to_le16(chks); cfpkt_add_trail(pkt, &data, 2); } else { cfpkt_pad_trail(pkt, 2); } len = cfpkt_getlen(pkt); data = cpu_to_le16(len); cfpkt_add_head(pkt, &data, 2); cfpkt_info(pkt)->hdr_len += 2; if (cfpkt_erroneous(pkt)) { pr_err("Packet is erroneous!\n"); cfpkt_destroy(pkt); return -EPROTO; } if (layr->dn == NULL) { cfpkt_destroy(pkt); return -ENODEV; } return layr->dn->transmit(layr->dn, pkt); } static void cffrml_ctrlcmd(struct cflayer *layr, enum caif_ctrlcmd ctrl, int phyid) { if (layr->up && layr->up->ctrlcmd) layr->up->ctrlcmd(layr->up, ctrl, layr->id); } void cffrml_put(struct cflayer *layr) { struct cffrml *this = container_obj(layr); if (layr != NULL && this->pcpu_refcnt != NULL) this_cpu_dec(*this->pcpu_refcnt); } void cffrml_hold(struct cflayer *layr) { struct cffrml *this = container_obj(layr); if (layr != NULL && this->pcpu_refcnt != NULL) this_cpu_inc(*this->pcpu_refcnt); } int cffrml_refcnt_read(struct cflayer *layr) { int i, refcnt = 0; struct cffrml *this = container_obj(layr); for_each_possible_cpu(i) refcnt += *per_cpu_ptr(this->pcpu_refcnt, i); return refcnt; } h>Dexuan Cui <decui@microsoft.com>2017-01-28 11:46:02 -0700 committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2017-01-31 10:59:48 +0100 commit433e19cf33d34bb6751c874a9c00980552fe508c (patch) treece6547ef2987fbb289fa28f03536328a42781651 /include/net/bluetooth parent191e885a2e130e639bb0c8ee350d7047294f2ce6 (diff)
Drivers: hv: vmbus: finally fix hv_need_to_signal_on_read()
Commit a389fcfd2cb5 ("Drivers: hv: vmbus: Fix signaling logic in hv_need_to_signal_on_read()") added the proper mb(), but removed the test "prev_write_sz < pending_sz" when making the signal decision. As a result, the guest can signal the host unnecessarily, and then the host can throttle the guest because the host thinks the guest is buggy or malicious; finally the user running stress test can perceive intermittent freeze of the guest. This patch brings back the test, and properly handles the in-place consumption APIs used by NetVSC (see get_next_pkt_raw(), put_pkt_raw() and commit_rd_index()). Fixes: a389fcfd2cb5 ("Drivers: hv: vmbus: Fix signaling logic in hv_need_to_signal_on_read()") Signed-off-by: Dexuan Cui <decui@microsoft.com> Reported-by: Rolf Neugebauer <rolf.neugebauer@docker.com> Tested-by: Rolf Neugebauer <rolf.neugebauer@docker.com> Cc: "K. Y. Srinivasan" <kys@microsoft.com> Cc: Haiyang Zhang <haiyangz@microsoft.com> Cc: Stephen Hemminger <sthemmin@microsoft.com> Cc: <stable@vger.kernel.org> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'include/net/bluetooth')