Module Name: src
Committed By: martin
Date: Tue Feb 23 18:50:21 UTC 2021
Modified Files:
src/sys/arch/xen/xen [netbsd-9]: xennetback_xenbus.c
Log Message:
Pull up following revision(s) (requested by jdolecek in ticket #1211):
sys/arch/xen/xen/xennetback_xenbus.c: revision 1.92 (via patch)
remove support for legacy rx-flip mode for xennet(4)/xvif(4), making
rx-copy (first shipped in NetBSD 6.0 in 2012) the only supported
mode
this is mostly to simplify maintenance and future development
rx-flip is not supported by Linux Dom0/DomU, and NetBSD Dom0/DomU
defaults to rx-copy for over 8 years now too, so there is little
need to keep the support for compatibility
besides compatibility there is no other reason to keep rx-flip -
page transfer is generally slower than copy due to necessary MMU/TLB
manipulation, especially on MP systems
To generate a diff of this commit:
cvs rdiff -u -r1.75 -r1.75.4.1 src/sys/arch/xen/xen/xennetback_xenbus.c
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/sys/arch/xen/xen/xennetback_xenbus.c
diff -u src/sys/arch/xen/xen/xennetback_xenbus.c:1.75 src/sys/arch/xen/xen/xennetback_xenbus.c:1.75.4.1
--- src/sys/arch/xen/xen/xennetback_xenbus.c:1.75 Sat Mar 9 08:42:25 2019
+++ src/sys/arch/xen/xen/xennetback_xenbus.c Tue Feb 23 18:50:21 2021
@@ -1,4 +1,4 @@
-/* $NetBSD: xennetback_xenbus.c,v 1.75 2019/03/09 08:42:25 maxv Exp $ */
+/* $NetBSD: xennetback_xenbus.c,v 1.75.4.1 2021/02/23 18:50:21 martin Exp $ */
/*
* Copyright (c) 2006 Manuel Bouyer.
@@ -25,7 +25,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: xennetback_xenbus.c,v 1.75 2019/03/09 08:42:25 maxv Exp $");
+__KERNEL_RCSID(0, "$NetBSD: xennetback_xenbus.c,v 1.75.4.1 2021/02/23 18:50:21 martin Exp $");
#include "opt_xen.h"
@@ -129,7 +129,6 @@ struct xnetback_instance {
void xvifattach(int);
static int xennetback_ifioctl(struct ifnet *, u_long, void *);
static void xennetback_ifstart(struct ifnet *);
-static void xennetback_ifsoftstart_transfer(void *);
static void xennetback_ifsoftstart_copy(void *);
static void xennetback_ifwatchdog(struct ifnet *);
static int xennetback_ifinit(struct ifnet *);
@@ -160,35 +159,10 @@ static struct xenbus_backend_driver xvif
*/
#define NB_XMIT_PAGES_BATCH 64
-/*
- * We will transfer a mapped page to the remote domain, and remap another
- * page in place immediately. For this we keep a list of pages available.
- * When the list is empty, we ask the hypervisor to give us
- * NB_XMIT_PAGES_BATCH pages back.
- */
-static unsigned long mcl_pages[NB_XMIT_PAGES_BATCH]; /* our physical pages */
-int mcl_pages_alloc; /* current index in mcl_pages */
-static int xennetback_get_mcl_page(paddr_t *);
-static void xennetback_get_new_mcl_pages(void);
-
-/*
- * If we can't transfer the mbuf directly, we have to copy it to a page which
- * will be transferred to the remote domain. We use a pool_cache for this.
- */
-pool_cache_t xmit_pages_cache;
-
/* arrays used in xennetback_ifstart(), too large to allocate on stack */
/* XXXSMP */
-static mmu_update_t xstart_mmu[NB_XMIT_PAGES_BATCH];
-static multicall_entry_t xstart_mcl[NB_XMIT_PAGES_BATCH + 1];
-static gnttab_transfer_t xstart_gop_transfer[NB_XMIT_PAGES_BATCH];
static gnttab_copy_t xstart_gop_copy[NB_XMIT_PAGES_BATCH];
static struct mbuf *mbufs_sent[NB_XMIT_PAGES_BATCH];
-static struct _pages_pool_free {
- vaddr_t va;
- paddr_t pa;
-} pages_pool_free[NB_XMIT_PAGES_BATCH];
-
static inline void
xni_pkt_unmap(struct xni_pkt *pkt, vaddr_t pkt_va)
@@ -200,31 +174,11 @@ xni_pkt_unmap(struct xni_pkt *pkt, vaddr
void
xvifattach(int n)
{
- int i;
- struct pglist mlist;
- struct vm_page *pg;
-
XENPRINTF(("xennetback_init\n"));
- /*
- * steal some non-managed pages to the VM system, to replace
- * mbuf cluster or xmit_pages_pool pages given to foreign domains.
- */
- if (uvm_pglistalloc(PAGE_SIZE * NB_XMIT_PAGES_BATCH, 0, 0xffffffff,
- 0, 0, &mlist, NB_XMIT_PAGES_BATCH, 0) != 0)
- panic("xennetback_init: uvm_pglistalloc");
- for (i = 0, pg = mlist.tqh_first; pg != NULL;
- pg = pg->pageq.queue.tqe_next, i++)
- mcl_pages[i] = xpmap_ptom(VM_PAGE_TO_PHYS(pg)) >> PAGE_SHIFT;
- if (i != NB_XMIT_PAGES_BATCH)
- panic("xennetback_init: %d mcl pages", i);
- mcl_pages_alloc = NB_XMIT_PAGES_BATCH - 1;
-
/* initialise pools */
pool_init(&xni_pkt_pool, sizeof(struct xni_pkt), 0, 0, 0,
"xnbpkt", NULL, IPL_VM);
- xmit_pages_cache = pool_cache_init(PAGE_SIZE, 0, 0, 0, "xnbxm", NULL,
- IPL_VM, NULL, NULL, NULL);
SLIST_INIT(&xnetback_instances);
mutex_init(&xnetback_lock, MUTEX_DEFAULT, IPL_NONE);
@@ -342,14 +296,6 @@ xennetback_xenbus_create(struct xenbus_d
xbusd->xbusd_path, err);
goto abort_xbt;
}
- err = xenbus_printf(xbt, xbusd->xbusd_path,
- "feature-rx-flip", "%d", 1);
- if (err) {
- aprint_error_ifnet(ifp,
- "failed to write %s/feature-rx-flip: %d\n",
- xbusd->xbusd_path, err);
- goto abort_xbt;
- }
} while ((err = xenbus_transaction_end(xbt, 0)) == EAGAIN);
if (err) {
aprint_error_ifnet(ifp,
@@ -472,21 +418,19 @@ xennetback_connect(struct xnetback_insta
}
err = xenbus_read_ul(NULL, xbusd->xbusd_otherend,
"request-rx-copy", &rx_copy, 10);
- if (err == ENOENT)
- rx_copy = 0;
- else if (err) {
+ if (err == ENOENT || !rx_copy) {
+ xenbus_dev_fatal(xbusd, err,
+ "%s/request-rx-copy not supported by frontend",
+ xbusd->xbusd_otherend);
+ return -1;
+ } else if (err) {
xenbus_dev_fatal(xbusd, err, "reading %s/request-rx-copy",
xbusd->xbusd_otherend);
return -1;
}
- if (rx_copy)
- xneti->xni_softintr = softint_establish(SOFTINT_NET,
- xennetback_ifsoftstart_copy, xneti);
- else
- xneti->xni_softintr = softint_establish(SOFTINT_NET,
- xennetback_ifsoftstart_transfer, xneti);
-
+ xneti->xni_softintr = softint_establish(SOFTINT_NET,
+ xennetback_ifsoftstart_copy, xneti);
if (xneti->xni_softintr == NULL) {
err = ENOMEM;
xenbus_dev_fatal(xbusd, ENOMEM,
@@ -662,48 +606,6 @@ xnetif_lookup(domid_t dom , uint32_t han
return found;
}
-/* get a page to replace a mbuf cluster page given to a domain */
-static int
-xennetback_get_mcl_page(paddr_t *map)
-{
- if (mcl_pages_alloc < 0) {
- /*
- * we exhausted our allocation. We can't allocate new ones yet
- * because the current pages may not have been loaned to
- * the remote domain yet. We have to let the caller do this.
- */
- return -1;
- }
-
- *map = ((paddr_t)mcl_pages[mcl_pages_alloc]) << PAGE_SHIFT;
- mcl_pages_alloc--;
- return 0;
-}
-
-static void
-xennetback_get_new_mcl_pages(void)
-{
- int nb_pages;
- struct xen_memory_reservation res;
-
- /* get some new pages. */
- set_xen_guest_handle(res.extent_start, mcl_pages);
- res.nr_extents = NB_XMIT_PAGES_BATCH;
- res.extent_order = 0;
- res.address_bits = 0;
- res.domid = DOMID_SELF;
-
- nb_pages = HYPERVISOR_memory_op(XENMEM_increase_reservation, &res);
- if (nb_pages <= 0) {
- printf("xennetback: can't get new mcl pages (%d)\n", nb_pages);
- return;
- }
- if (nb_pages != NB_XMIT_PAGES_BATCH)
- printf("xennetback: got only %d new mcl pages\n", nb_pages);
-
- mcl_pages_alloc = nb_pages - 1;
-}
-
static inline void
xennetback_tx_response(struct xnetback_instance *xneti, int id, int status)
{
@@ -965,255 +867,6 @@ xennetback_ifstart(struct ifnet *ifp)
softint_schedule(xneti->xni_softintr);
}
-static void
-xennetback_ifsoftstart_transfer(void *arg)
-{
- struct xnetback_instance *xneti = arg;
- struct ifnet *ifp = &xneti->xni_if;
- struct mbuf *m;
- vaddr_t xmit_va;
- paddr_t xmit_pa;
- paddr_t xmit_ma;
- paddr_t newp_ma = 0; /* XXX gcc */
- int i, j, nppitems;
- mmu_update_t *mmup;
- multicall_entry_t *mclp;
- netif_rx_response_t *rxresp;
- netif_rx_request_t rxreq;
- RING_IDX req_prod, resp_prod;
- int do_event = 0;
- gnttab_transfer_t *gop;
- int id, offset;
-
- XENPRINTF(("xennetback_ifsoftstart_transfer "));
- int s = splnet();
- if (__predict_false(
- (ifp->if_flags & (IFF_RUNNING|IFF_OACTIVE)) != IFF_RUNNING)) {
- splx(s);
- return;
- }
-
- while (!IFQ_IS_EMPTY(&ifp->if_snd)) {
- XENPRINTF(("pkt\n"));
- req_prod = xneti->xni_rxring.sring->req_prod;
- resp_prod = xneti->xni_rxring.rsp_prod_pvt;
- xen_rmb();
-
- mmup = xstart_mmu;
- mclp = xstart_mcl;
- gop = xstart_gop_transfer;
- for (nppitems = 0, i = 0; !IFQ_IS_EMPTY(&ifp->if_snd);) {
- XENPRINTF(("have a packet\n"));
- IFQ_POLL(&ifp->if_snd, m);
- if (__predict_false(m == NULL))
- panic("xennetback_ifstart: IFQ_POLL");
- if (__predict_false(
- req_prod == xneti->xni_rxring.req_cons ||
- xneti->xni_rxring.req_cons - resp_prod ==
- NET_RX_RING_SIZE)) {
- /* out of ring space */
- XENPRINTF(("xennetback_ifstart: ring full "
- "req_prod 0x%x req_cons 0x%x resp_prod "
- "0x%x\n",
- req_prod, xneti->xni_rxring.req_cons,
- resp_prod));
- ifp->if_timer = 1;
- break;
- }
- if (__predict_false(i == NB_XMIT_PAGES_BATCH))
- break; /* we filled the array */
- if (__predict_false(
- xennetback_get_mcl_page(&newp_ma) != 0))
- break; /* out of memory */
- if ((m->m_flags & M_EXT_CLUSTER) != 0 &&
- !M_READONLY(m) && MCLBYTES == PAGE_SIZE) {
- /* we can give this page away */
- xmit_pa = m->m_ext.ext_paddr;
- xmit_ma = xpmap_ptom(xmit_pa);
- xmit_va = (vaddr_t)m->m_ext.ext_buf;
- KASSERT(xmit_pa != M_PADDR_INVALID);
- KASSERT((xmit_va & PAGE_MASK) == 0);
- offset = m->m_data - m->m_ext.ext_buf;
- } else {
- /* we have to copy the packet */
- xmit_va = (vaddr_t)pool_cache_get_paddr(
- xmit_pages_cache, PR_NOWAIT, &xmit_pa);
- if (__predict_false(xmit_va == 0))
- break; /* out of memory */
-
- KASSERT(xmit_pa != POOL_PADDR_INVALID);
- xmit_ma = xpmap_ptom(xmit_pa);
- XENPRINTF(("xennetback_get_xmit_page: got va "
- "0x%x ma 0x%x\n", (u_int)xmit_va,
- (u_int)xmit_ma));
- m_copydata(m, 0, m->m_pkthdr.len,
- (char *)xmit_va + LINUX_REQUESTED_OFFSET);
- offset = LINUX_REQUESTED_OFFSET;
- pages_pool_free[nppitems].va = xmit_va;
- pages_pool_free[nppitems].pa = xmit_pa;
- nppitems++;
- }
- /* start filling ring */
- RING_COPY_REQUEST(&xneti->xni_rxring,
- xneti->xni_rxring.req_cons, &rxreq);
- gop->ref = rxreq.gref;
- id = rxreq.id;
- xen_rmb();
- xneti->xni_rxring.req_cons++;
- rxresp = RING_GET_RESPONSE(&xneti->xni_rxring,
- resp_prod);
- rxresp->id = id;
- rxresp->offset = offset;
- rxresp->status = m->m_pkthdr.len;
- if ((m->m_pkthdr.csum_flags &
- (M_CSUM_TCPv4 | M_CSUM_UDPv4)) != 0) {
- rxresp->flags = NETRXF_csum_blank;
- } else {
- rxresp->flags = 0;
- }
- /*
- * transfers the page containing the packet to the
- * remote domain, and map newp in place.
- */
- xpmap_ptom_map(xmit_pa, newp_ma);
- MULTI_update_va_mapping(mclp, xmit_va,
- newp_ma | PTE_P | PTE_W | PTE_A | PTE_D | xpmap_pg_nx, 0);
- mclp++;
- gop->mfn = xmit_ma >> PAGE_SHIFT;
- gop->domid = xneti->xni_domid;
- gop++;
-
- mmup->ptr = newp_ma | MMU_MACHPHYS_UPDATE;
- mmup->val = xmit_pa >> PAGE_SHIFT;
- mmup++;
-
- /* done with this packet */
- IFQ_DEQUEUE(&ifp->if_snd, m);
- mbufs_sent[i] = m;
- resp_prod++;
- i++; /* this packet has been queued */
- ifp->if_opackets++;
- bpf_mtap(ifp, m, BPF_D_OUT);
- }
- if (i != 0) {
- /*
- * We may have allocated buffers which have entries
- * outstanding in the page update queue -- make sure
- * we flush those first!
- */
- int svm = splvm();
- xpq_flush_queue();
- splx(svm);
- mclp[-1].args[MULTI_UVMFLAGS_INDEX] =
- UVMF_TLB_FLUSH|UVMF_ALL;
- mclp->op = __HYPERVISOR_mmu_update;
- mclp->args[0] = (unsigned long)xstart_mmu;
- mclp->args[1] = i;
- mclp->args[2] = 0;
- mclp->args[3] = DOMID_SELF;
- mclp++;
- /* update the MMU */
- if (HYPERVISOR_multicall(xstart_mcl, i + 1) != 0) {
- panic("%s: HYPERVISOR_multicall failed",
- ifp->if_xname);
- }
- for (j = 0; j < i + 1; j++) {
- if (xstart_mcl[j].result != 0) {
- printf("%s: xstart_mcl[%d] "
- "failed (%lu)\n", ifp->if_xname,
- j, xstart_mcl[j].result);
- printf("%s: req_prod %u req_cons "
- "%u rsp_prod %u rsp_prod_pvt %u "
- "i %u\n",
- ifp->if_xname,
- xneti->xni_rxring.sring->req_prod,
- xneti->xni_rxring.req_cons,
- xneti->xni_rxring.sring->rsp_prod,
- xneti->xni_rxring.rsp_prod_pvt,
- i);
- }
- }
- if (HYPERVISOR_grant_table_op(GNTTABOP_transfer,
- xstart_gop_transfer, i) != 0) {
- panic("%s: GNTTABOP_transfer failed",
- ifp->if_xname);
- }
-
- for (j = 0; j < i; j++) {
- if (xstart_gop_transfer[j].status != GNTST_okay) {
- printf("%s GNTTABOP_transfer[%d] %d\n",
- ifp->if_xname,
- j, xstart_gop_transfer[j].status);
- printf("%s: req_prod %u req_cons "
- "%u rsp_prod %u rsp_prod_pvt %u "
- "i %d\n",
- ifp->if_xname,
- xneti->xni_rxring.sring->req_prod,
- xneti->xni_rxring.req_cons,
- xneti->xni_rxring.sring->rsp_prod,
- xneti->xni_rxring.rsp_prod_pvt,
- i);
- rxresp = RING_GET_RESPONSE(
- &xneti->xni_rxring,
- xneti->xni_rxring.rsp_prod_pvt + j);
- rxresp->status = NETIF_RSP_ERROR;
- }
- }
-
- /* update pointer */
- KASSERT(
- xneti->xni_rxring.rsp_prod_pvt + i == resp_prod);
- xneti->xni_rxring.rsp_prod_pvt = resp_prod;
- RING_PUSH_RESPONSES_AND_CHECK_NOTIFY(
- &xneti->xni_rxring, j);
- if (j)
- do_event = 1;
- /* now we can free the mbufs */
- for (j = 0; j < i; j++) {
- m_freem(mbufs_sent[j]);
- }
- for (j = 0; j < nppitems; j++) {
- pool_cache_put_paddr(xmit_pages_cache,
- (void *)pages_pool_free[j].va,
- pages_pool_free[j].pa);
- }
- }
- /* send event */
- if (do_event) {
- xen_rmb();
- XENPRINTF(("%s receive event\n",
- xneti->xni_if.if_xname));
- hypervisor_notify_via_evtchn(xneti->xni_evtchn);
- do_event = 0;
- }
- /* check if we need to get back some pages */
- if (mcl_pages_alloc < 0) {
- xennetback_get_new_mcl_pages();
- if (mcl_pages_alloc < 0) {
- /*
- * setup the watchdog to try again, because
- * xennetback_ifstart() will never be called
- * again if queue is full.
- */
- printf("xennetback_ifstart: no mcl_pages\n");
- ifp->if_timer = 1;
- break;
- }
- }
- /*
- * note that we don't use RING_FINAL_CHECK_FOR_REQUESTS()
- * here, as the frontend doesn't notify when adding
- * requests anyway
- */
- if (__predict_false(
- !RING_HAS_UNCONSUMED_REQUESTS(&xneti->xni_rxring))) {
- /* ring full */
- break;
- }
- }
- splx(s);
-}
-
/*
* sighly different from m_dup(); for some reason m_dup() can return
* a chain where the data area can cross a page boundary.
