Skip to content
Navigation Menu
Toggle navigation
Sign in
In this repository
All GitHub Enterprise
↵
Jump to
↵
No suggested jump to results
In this repository
All GitHub Enterprise
↵
Jump to
↵
In this organization
All GitHub Enterprise
↵
Jump to
↵
In this repository
All GitHub Enterprise
↵
Jump to
↵
Sign in
Reseting focus
You signed in with another tab or window.
Reload
to refresh your session.
You signed out in another tab or window.
Reload
to refresh your session.
You switched accounts on another tab or window.
Reload
to refresh your session.
Dismiss alert
{{ message }}
mariux64
/
linux
Public
Notifications
You must be signed in to change notification settings
Fork
0
Star
0
Code
Issues
2
Pull requests
0
Actions
Projects
0
Wiki
Security
Insights
Additional navigation options
Code
Issues
Pull requests
Actions
Projects
Wiki
Security
Insights
Files
ccf8f7d
Documentation
LICENSES
arch
block
certs
crypto
drivers
accel
accessibility
acpi
amba
android
ata
atm
auxdisplay
base
bcma
block
bluetooth
bus
cdrom
char
clk
clocksource
comedi
connector
counter
cpufreq
cpuidle
crypto
cxl
dax
dca
devfreq
dio
dma-buf
dma
edac
eisa
extcon
firewire
firmware
fpga
fsi
gnss
gpio
gpu
greybus
hid
hsi
hte
hv
hwmon
hwspinlock
hwtracing
i2c
i3c
idle
iio
infiniband
input
interconnect
iommu
ipack
irqchip
isdn
leds
macintosh
mailbox
mcb
md
media
memory
memstick
message
mfd
misc
mmc
most
mtd
mux
net
appletalk
arcnet
bonding
caif
can
dsa
ethernet
fddi
fjes
hamradio
hippi
hyperv
ieee802154
ipa
ipvlan
mctp
mdio
netdevsim
pcs
phy
plip
ppp
pse-pd
slip
team
thunderbolt
usb
vmxnet3
vxlan
wan
wireguard
wireless
wwan
xen-netback
Makefile
common.h
hash.c
interface.c
netback.c
rx.c
xenbus.c
Kconfig
LICENSE.SRC
Makefile
Space.c
amt.c
bareudp.c
dummy.c
eql.c
geneve.c
gtp.c
ifb.c
loopback.c
macsec.c
macvlan.c
macvtap.c
mdio.c
mhi_net.c
mii.c
net_failover.c
netconsole.c
nlmon.c
ntb_netdev.c
rionet.c
sb1000.c
sungem_phy.c
tap.c
tun.c
veth.c
virtio_net.c
vrf.c
vsockmon.c
xen-netfront.c
nfc
ntb
nubus
nvdimm
nvme
nvmem
of
opp
parisc
parport
pci
pcmcia
peci
perf
phy
pinctrl
platform
pnp
power
powercap
pps
ps3
ptp
pwm
rapidio
ras
regulator
remoteproc
reset
rpmsg
rtc
s390
sbus
scsi
sh
siox
slimbus
soc
soundwire
spi
spmi
ssb
staging
target
tc
tee
thermal
thunderbolt
tty
ufs
uio
usb
vdpa
vfio
vhost
video
virt
virtio
vlynq
w1
watchdog
xen
zorro
Kconfig
Makefile
fs
include
init
io_uring
ipc
kernel
lib
mm
net
rust
samples
scripts
security
sound
tools
usr
virt
.clang-format
.cocciconfig
.get_maintainer.ignore
.gitattributes
.gitignore
.mailmap
.rustfmt.toml
COPYING
CREDITS
Kbuild
Kconfig
MAINTAINERS
Makefile
README
Breadcrumbs
linux
/
drivers
/
net
/
xen-netback
/
netback.c
Blame
Blame
Latest commit
History
History
1736 lines (1431 loc) · 45.7 KB
Breadcrumbs
linux
/
drivers
/
net
/
xen-netback
/
netback.c
Top
File metadata and controls
Code
Blame
1736 lines (1431 loc) · 45.7 KB
Raw
/* * Back-end of the driver for virtual network devices. This portion of the * driver exports a 'unified' network-device interface that can be accessed * by any operating system that implements a compatible front end. A * reference front-end implementation can be found in: * drivers/net/xen-netfront.c * * Copyright (c) 2002-2005, K A Fraser * * 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; or, when distributed * separately from the Linux kernel or incorporated into other * software packages, subject to the following license: * * Permission is hereby granted, free of charge, to any person obtaining a copy * of this source file (the "Software"), to deal in the Software without * restriction, including without limitation the rights to use, copy, modify, * merge, publish, distribute, sublicense, and/or sell copies of the Software, * and to permit persons to whom the Software is furnished to do so, subject to * the following conditions: * * The above copyright notice and this permission notice shall be included in * all copies or substantial portions of the Software. * * 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 "common.h" #include <linux/kthread.h> #include <linux/if_vlan.h> #include <linux/udp.h> #include <linux/highmem.h> #include <net/tcp.h> #include <xen/xen.h> #include <xen/events.h> #include <xen/interface/memory.h> #include <xen/page.h> #include <asm/xen/hypercall.h> /* Provide an option to disable split event channels at load time as * event channels are limited resource. Split event channels are * enabled by default. */ bool separate_tx_rx_irq = true; module_param(separate_tx_rx_irq, bool, 0644); /* The time that packets can stay on the guest Rx internal queue * before they are dropped. */ unsigned int rx_drain_timeout_msecs = 10000; module_param(rx_drain_timeout_msecs, uint, 0444); /* The length of time before the frontend is considered unresponsive * because it isn't providing Rx slots. */ unsigned int rx_stall_timeout_msecs = 60000; module_param(rx_stall_timeout_msecs, uint, 0444); #define MAX_QUEUES_DEFAULT 8 unsigned int xenvif_max_queues; module_param_named(max_queues, xenvif_max_queues, uint, 0644); MODULE_PARM_DESC(max_queues, "Maximum number of queues per virtual interface"); /* * This is the maximum slots a skb can have. If a guest sends a skb * which exceeds this limit it is considered malicious. */ #define FATAL_SKB_SLOTS_DEFAULT 20 static unsigned int fatal_skb_slots = FATAL_SKB_SLOTS_DEFAULT; module_param(fatal_skb_slots, uint, 0444); /* The amount to copy out of the first guest Tx slot into the skb's * linear area. If the first slot has more data, it will be mapped * and put into the first frag. * * This is sized to avoid pulling headers from the frags for most * TCP/IP packets. */ #define XEN_NETBACK_TX_COPY_LEN 128 /* This is the maximum number of flows in the hash cache. */ #define XENVIF_HASH_CACHE_SIZE_DEFAULT 64 unsigned int xenvif_hash_cache_size = XENVIF_HASH_CACHE_SIZE_DEFAULT; module_param_named(hash_cache_size, xenvif_hash_cache_size, uint, 0644); MODULE_PARM_DESC(hash_cache_size, "Number of flows in the hash cache"); /* The module parameter tells that we have to put data * for xen-netfront with the XDP_PACKET_HEADROOM offset * needed for XDP processing */ bool provides_xdp_headroom = true; module_param(provides_xdp_headroom, bool, 0644); static void xenvif_idx_release(struct xenvif_queue *queue, u16 pending_idx, u8 status); static void make_tx_response(struct xenvif_queue *queue, struct xen_netif_tx_request *txp, unsigned int extra_count, s8 st); static void push_tx_responses(struct xenvif_queue *queue); static void xenvif_idx_unmap(struct xenvif_queue *queue, u16 pending_idx); static inline int tx_work_todo(struct xenvif_queue *queue); static inline unsigned long idx_to_pfn(struct xenvif_queue *queue, u16 idx) { return page_to_pfn(queue->mmap_pages[idx]); } static inline unsigned long idx_to_kaddr(struct xenvif_queue *queue, u16 idx) { return (unsigned long)pfn_to_kaddr(idx_to_pfn(queue, idx)); } #define callback_param(vif, pending_idx) \ (vif->pending_tx_info[pending_idx].callback_struct) /* Find the containing VIF's structure from a pointer in pending_tx_info array */ static inline struct xenvif_queue *ubuf_to_queue(const struct ubuf_info_msgzc *ubuf) { u16 pending_idx = ubuf->desc; struct pending_tx_info *temp = container_of(ubuf, struct pending_tx_info, callback_struct); return container_of(temp - pending_idx, struct xenvif_queue, pending_tx_info[0]); } static u16 frag_get_pending_idx(skb_frag_t *frag) { return (u16)skb_frag_off(frag); } static void frag_set_pending_idx(skb_frag_t *frag, u16 pending_idx) { skb_frag_off_set(frag, pending_idx); } static inline pending_ring_idx_t pending_index(unsigned i) { return i & (MAX_PENDING_REQS-1); } void xenvif_kick_thread(struct xenvif_queue *queue) { wake_up(&queue->wq); } void xenvif_napi_schedule_or_enable_events(struct xenvif_queue *queue) { int more_to_do; RING_FINAL_CHECK_FOR_REQUESTS(&queue->tx, more_to_do); if (more_to_do) napi_schedule(&queue->napi); else if (atomic_fetch_andnot(NETBK_TX_EOI | NETBK_COMMON_EOI, &queue->eoi_pending) & (NETBK_TX_EOI | NETBK_COMMON_EOI)) xen_irq_lateeoi(queue->tx_irq, 0); } static void tx_add_credit(struct xenvif_queue *queue) { unsigned long max_burst, max_credit; /* * Allow a burst big enough to transmit a jumbo packet of up to 128kB. * Otherwise the interface can seize up due to insufficient credit. */ max_burst = max(131072UL, queue->credit_bytes); /* Take care that adding a new chunk of credit doesn't wrap to zero. */ max_credit = queue->remaining_credit + queue->credit_bytes; if (max_credit < queue->remaining_credit) max_credit = ULONG_MAX; /* wrapped: clamp to ULONG_MAX */ queue->remaining_credit = min(max_credit, max_burst); queue->rate_limited = false; } void xenvif_tx_credit_callback(struct timer_list *t) { struct xenvif_queue *queue = from_timer(queue, t, credit_timeout); tx_add_credit(queue); xenvif_napi_schedule_or_enable_events(queue); } static void xenvif_tx_err(struct xenvif_queue *queue, struct xen_netif_tx_request *txp, unsigned int extra_count, RING_IDX end) { RING_IDX cons = queue->tx.req_cons; unsigned long flags; do { spin_lock_irqsave(&queue->response_lock, flags); make_tx_response(queue, txp, extra_count, XEN_NETIF_RSP_ERROR); push_tx_responses(queue); spin_unlock_irqrestore(&queue->response_lock, flags); if (cons == end) break; RING_COPY_REQUEST(&queue->tx, cons++, txp); extra_count = 0; /* only the first frag can have extras */ } while (1); queue->tx.req_cons = cons; } static void xenvif_fatal_tx_err(struct xenvif *vif) { netdev_err(vif->dev, "fatal error; disabling device\n"); vif->disabled = true; /* Disable the vif from queue 0's kthread */ if (vif->num_queues) xenvif_kick_thread(&vif->queues[0]); } static int xenvif_count_requests(struct xenvif_queue *queue, struct xen_netif_tx_request *first, unsigned int extra_count, struct xen_netif_tx_request *txp, int work_to_do) { RING_IDX cons = queue->tx.req_cons; int slots = 0; int drop_err = 0; int more_data; if (!(first->flags & XEN_NETTXF_more_data)) return 0; do { struct xen_netif_tx_request dropped_tx = { 0 }; if (slots >= work_to_do) { netdev_err(queue->vif->dev, "Asked for %d slots but exceeds this limit\n", work_to_do); xenvif_fatal_tx_err(queue->vif); return -ENODATA; } /* This guest is really using too many slots and * considered malicious. */ if (unlikely(slots >= fatal_skb_slots)) { netdev_err(queue->vif->dev, "Malicious frontend using %d slots, threshold %u\n", slots, fatal_skb_slots); xenvif_fatal_tx_err(queue->vif); return -E2BIG; } /* Xen network protocol had implicit dependency on * MAX_SKB_FRAGS. XEN_NETBK_LEGACY_SLOTS_MAX is set to * the historical MAX_SKB_FRAGS value 18 to honor the * same behavior as before. Any packet using more than * 18 slots but less than fatal_skb_slots slots is * dropped */ if (!drop_err && slots >= XEN_NETBK_LEGACY_SLOTS_MAX) { if (net_ratelimit()) netdev_dbg(queue->vif->dev, "Too many slots (%d) exceeding limit (%d), dropping packet\n", slots, XEN_NETBK_LEGACY_SLOTS_MAX); drop_err = -E2BIG; } if (drop_err) txp = &dropped_tx; RING_COPY_REQUEST(&queue->tx, cons + slots, txp); /* If the guest submitted a frame >= 64 KiB then * first->size overflowed and following slots will * appear to be larger than the frame. * * This cannot be fatal error as there are buggy * frontends that do this. * * Consume all slots and drop the packet. */ if (!drop_err && txp->size > first->size) { if (net_ratelimit()) netdev_dbg(queue->vif->dev, "Invalid tx request, slot size %u > remaining size %u\n", txp->size, first->size); drop_err = -EIO; } first->size -= txp->size; slots++; if (unlikely((txp->offset + txp->size) > XEN_PAGE_SIZE)) { netdev_err(queue->vif->dev, "Cross page boundary, txp->offset: %u, size: %u\n", txp->offset, txp->size); xenvif_fatal_tx_err(queue->vif); return -EINVAL; } more_data = txp->flags & XEN_NETTXF_more_data; if (!drop_err) txp++; } while (more_data); if (drop_err) { xenvif_tx_err(queue, first, extra_count, cons + slots); return drop_err; } return slots; } struct xenvif_tx_cb { u16 copy_pending_idx[XEN_NETBK_LEGACY_SLOTS_MAX + 1]; u8 copy_count; }; #define XENVIF_TX_CB(skb) ((struct xenvif_tx_cb *)(skb)->cb) #define copy_pending_idx(skb, i) (XENVIF_TX_CB(skb)->copy_pending_idx[i]) #define copy_count(skb) (XENVIF_TX_CB(skb)->copy_count) static inline void xenvif_tx_create_map_op(struct xenvif_queue *queue, u16 pending_idx, struct xen_netif_tx_request *txp, unsigned int extra_count, struct gnttab_map_grant_ref *mop) { queue->pages_to_map[mop-queue->tx_map_ops] = queue->mmap_pages[pending_idx]; gnttab_set_map_op(mop, idx_to_kaddr(queue, pending_idx), GNTMAP_host_map | GNTMAP_readonly, txp->gref, queue->vif->domid); memcpy(&queue->pending_tx_info[pending_idx].req, txp, sizeof(*txp)); queue->pending_tx_info[pending_idx].extra_count = extra_count; } static inline struct sk_buff *xenvif_alloc_skb(unsigned int size) { struct sk_buff *skb = alloc_skb(size + NET_SKB_PAD + NET_IP_ALIGN, GFP_ATOMIC | __GFP_NOWARN); if (unlikely(skb == NULL)) return NULL; /* Packets passed to netif_rx() must have some headroom. */ skb_reserve(skb, NET_SKB_PAD + NET_IP_ALIGN); /* Initialize it here to avoid later surprises */ skb_shinfo(skb)->destructor_arg = NULL; return skb; } static void xenvif_get_requests(struct xenvif_queue *queue, struct sk_buff *skb, struct xen_netif_tx_request *first, struct xen_netif_tx_request *txfrags, unsigned *copy_ops, unsigned *map_ops, unsigned int frag_overflow, struct sk_buff *nskb, unsigned int extra_count, unsigned int data_len) { struct skb_shared_info *shinfo = skb_shinfo(skb); skb_frag_t *frags = shinfo->frags; u16 pending_idx; pending_ring_idx_t index; unsigned int nr_slots; struct gnttab_copy *cop = queue->tx_copy_ops + *copy_ops; struct gnttab_map_grant_ref *gop = queue->tx_map_ops + *map_ops; struct xen_netif_tx_request *txp = first; nr_slots = shinfo->nr_frags + 1; copy_count(skb) = 0; /* Create copy ops for exactly data_len bytes into the skb head. */ __skb_put(skb, data_len); while (data_len > 0) { int amount = data_len > txp->size ? txp->size : data_len; cop->source.u.ref = txp->gref; cop->source.domid = queue->vif->domid; cop->source.offset = txp->offset; cop->dest.domid = DOMID_SELF; cop->dest.offset = (offset_in_page(skb->data + skb_headlen(skb) - data_len)) & ~XEN_PAGE_MASK; cop->dest.u.gmfn = virt_to_gfn(skb->data + skb_headlen(skb) - data_len); cop->len = amount; cop->flags = GNTCOPY_source_gref; index = pending_index(queue->pending_cons); pending_idx = queue->pending_ring[index]; callback_param(queue, pending_idx).ctx = NULL; copy_pending_idx(skb, copy_count(skb)) = pending_idx; copy_count(skb)++; cop++; data_len -= amount; if (amount == txp->size) { /* The copy op covered the full tx_request */ memcpy(&queue->pending_tx_info[pending_idx].req, txp, sizeof(*txp)); queue->pending_tx_info[pending_idx].extra_count = (txp == first) ? extra_count : 0; if (txp == first) txp = txfrags; else txp++; queue->pending_cons++; nr_slots--; } else { /* The copy op partially covered the tx_request. * The remainder will be mapped. */ txp->offset += amount; txp->size -= amount; } } for (shinfo->nr_frags = 0; shinfo->nr_frags < nr_slots; shinfo->nr_frags++, gop++) { index = pending_index(queue->pending_cons++); pending_idx = queue->pending_ring[index]; xenvif_tx_create_map_op(queue, pending_idx, txp, txp == first ? extra_count : 0, gop); frag_set_pending_idx(&frags[shinfo->nr_frags], pending_idx); if (txp == first) txp = txfrags; else txp++; } if (frag_overflow) { shinfo = skb_shinfo(nskb); frags = shinfo->frags; for (shinfo->nr_frags = 0; shinfo->nr_frags < frag_overflow; shinfo->nr_frags++, txp++, gop++) { index = pending_index(queue->pending_cons++); pending_idx = queue->pending_ring[index]; xenvif_tx_create_map_op(queue, pending_idx, txp, 0, gop); frag_set_pending_idx(&frags[shinfo->nr_frags], pending_idx); } skb_shinfo(skb)->frag_list = nskb; } (*copy_ops) = cop - queue->tx_copy_ops; (*map_ops) = gop - queue->tx_map_ops; } static inline void xenvif_grant_handle_set(struct xenvif_queue *queue, u16 pending_idx, grant_handle_t handle) { if (unlikely(queue->grant_tx_handle[pending_idx] != NETBACK_INVALID_HANDLE)) { netdev_err(queue->vif->dev, "Trying to overwrite active handle! pending_idx: 0x%x\n", pending_idx); BUG(); } queue->grant_tx_handle[pending_idx] = handle; } static inline void xenvif_grant_handle_reset(struct xenvif_queue *queue, u16 pending_idx) { if (unlikely(queue->grant_tx_handle[pending_idx] == NETBACK_INVALID_HANDLE)) { netdev_err(queue->vif->dev, "Trying to unmap invalid handle! pending_idx: 0x%x\n", pending_idx); BUG(); } queue->grant_tx_handle[pending_idx] = NETBACK_INVALID_HANDLE; } static int xenvif_tx_check_gop(struct xenvif_queue *queue, struct sk_buff *skb, struct gnttab_map_grant_ref **gopp_map, struct gnttab_copy **gopp_copy) { struct gnttab_map_grant_ref *gop_map = *gopp_map; u16 pending_idx; /* This always points to the shinfo of the skb being checked, which * could be either the first or the one on the frag_list */ struct skb_shared_info *shinfo = skb_shinfo(skb); /* If this is non-NULL, we are currently checking the frag_list skb, and * this points to the shinfo of the first one */ struct skb_shared_info *first_shinfo = NULL; int nr_frags = shinfo->nr_frags; const bool sharedslot = nr_frags && frag_get_pending_idx(&shinfo->frags[0]) == copy_pending_idx(skb, copy_count(skb) - 1); int i, err = 0; for (i = 0; i < copy_count(skb); i++) { int newerr; /* Check status of header. */ pending_idx = copy_pending_idx(skb, i); newerr = (*gopp_copy)->status; if (likely(!newerr)) { /* The first frag might still have this slot mapped */ if (i < copy_count(skb) - 1 || !sharedslot) xenvif_idx_release(queue, pending_idx, XEN_NETIF_RSP_OKAY); } else { err = newerr; if (net_ratelimit()) netdev_dbg(queue->vif->dev, "Grant copy of header failed! status: %d pending_idx: %u ref: %u\n", (*gopp_copy)->status, pending_idx, (*gopp_copy)->source.u.ref); /* The first frag might still have this slot mapped */ if (i < copy_count(skb) - 1 || !sharedslot) xenvif_idx_release(queue, pending_idx, XEN_NETIF_RSP_ERROR); } (*gopp_copy)++; } check_frags: for (i = 0; i < nr_frags; i++, gop_map++) { int j, newerr; pending_idx = frag_get_pending_idx(&shinfo->frags[i]); /* Check error status: if okay then remember grant handle. */ newerr = gop_map->status; if (likely(!newerr)) { xenvif_grant_handle_set(queue, pending_idx, gop_map->handle); /* Had a previous error? Invalidate this fragment. */ if (unlikely(err)) { xenvif_idx_unmap(queue, pending_idx); /* If the mapping of the first frag was OK, but * the header's copy failed, and they are * sharing a slot, send an error */ if (i == 0 && !first_shinfo && sharedslot) xenvif_idx_release(queue, pending_idx, XEN_NETIF_RSP_ERROR); else xenvif_idx_release(queue, pending_idx, XEN_NETIF_RSP_OKAY); } continue; } /* Error on this fragment: respond to client with an error. */ if (net_ratelimit()) netdev_dbg(queue->vif->dev, "Grant map of %d. frag failed! status: %d pending_idx: %u ref: %u\n", i, gop_map->status, pending_idx, gop_map->ref); xenvif_idx_release(queue, pending_idx, XEN_NETIF_RSP_ERROR); /* Not the first error? Preceding frags already invalidated. */ if (err) continue; /* Invalidate preceding fragments of this skb. */ for (j = 0; j < i; j++) { pending_idx = frag_get_pending_idx(&shinfo->frags[j]); xenvif_idx_unmap(queue, pending_idx); xenvif_idx_release(queue, pending_idx, XEN_NETIF_RSP_OKAY); } /* And if we found the error while checking the frag_list, unmap * the first skb's frags */ if (first_shinfo) { for (j = 0; j < first_shinfo->nr_frags; j++) { pending_idx = frag_get_pending_idx(&first_shinfo->frags[j]); xenvif_idx_unmap(queue, pending_idx); xenvif_idx_release(queue, pending_idx, XEN_NETIF_RSP_OKAY); } } /* Remember the error: invalidate all subsequent fragments. */ err = newerr; } if (skb_has_frag_list(skb) && !first_shinfo) { first_shinfo = shinfo; shinfo = skb_shinfo(shinfo->frag_list); nr_frags = shinfo->nr_frags; goto check_frags; } *gopp_map = gop_map; return err; } static void xenvif_fill_frags(struct xenvif_queue *queue, struct sk_buff *skb) { struct skb_shared_info *shinfo = skb_shinfo(skb); int nr_frags = shinfo->nr_frags; int i; u16 prev_pending_idx = INVALID_PENDING_IDX; for (i = 0; i < nr_frags; i++) { skb_frag_t *frag = shinfo->frags + i; struct xen_netif_tx_request *txp; struct page *page; u16 pending_idx; pending_idx = frag_get_pending_idx(frag); /* If this is not the first frag, chain it to the previous*/ if (prev_pending_idx == INVALID_PENDING_IDX) skb_shinfo(skb)->destructor_arg = &callback_param(queue, pending_idx); else callback_param(queue, prev_pending_idx).ctx = &callback_param(queue, pending_idx); callback_param(queue, pending_idx).ctx = NULL; prev_pending_idx = pending_idx; txp = &queue->pending_tx_info[pending_idx].req; page = virt_to_page(idx_to_kaddr(queue, pending_idx)); __skb_fill_page_desc(skb, i, page, txp->offset, txp->size); skb->len += txp->size; skb->data_len += txp->size; skb->truesize += txp->size; /* Take an extra reference to offset network stack's put_page */ get_page(queue->mmap_pages[pending_idx]); } } static int xenvif_get_extras(struct xenvif_queue *queue, struct xen_netif_extra_info *extras, unsigned int *extra_count, int work_to_do) { struct xen_netif_extra_info extra; RING_IDX cons = queue->tx.req_cons; do { if (unlikely(work_to_do-- <= 0)) { netdev_err(queue->vif->dev, "Missing extra info\n"); xenvif_fatal_tx_err(queue->vif); return -EBADR; } RING_COPY_REQUEST(&queue->tx, cons, &extra); queue->tx.req_cons = ++cons; (*extra_count)++; if (unlikely(!extra.type || extra.type >= XEN_NETIF_EXTRA_TYPE_MAX)) { netdev_err(queue->vif->dev, "Invalid extra type: %d\n", extra.type); xenvif_fatal_tx_err(queue->vif); return -EINVAL; } memcpy(&extras[extra.type - 1], &extra, sizeof(extra)); } while (extra.flags & XEN_NETIF_EXTRA_FLAG_MORE); return work_to_do; } static int xenvif_set_skb_gso(struct xenvif *vif, struct sk_buff *skb, struct xen_netif_extra_info *gso) { if (!gso->u.gso.size) { netdev_err(vif->dev, "GSO size must not be zero.\n"); xenvif_fatal_tx_err(vif); return -EINVAL; } switch (gso->u.gso.type) { case XEN_NETIF_GSO_TYPE_TCPV4: skb_shinfo(skb)->gso_type = SKB_GSO_TCPV4; break; case XEN_NETIF_GSO_TYPE_TCPV6: skb_shinfo(skb)->gso_type = SKB_GSO_TCPV6; break; default: netdev_err(vif->dev, "Bad GSO type %d.\n", gso->u.gso.type); xenvif_fatal_tx_err(vif); return -EINVAL; } skb_shinfo(skb)->gso_size = gso->u.gso.size; /* gso_segs will be calculated later */ return 0; } static int checksum_setup(struct xenvif_queue *queue, struct sk_buff *skb) { bool recalculate_partial_csum = false; /* A GSO SKB must be CHECKSUM_PARTIAL. However some buggy * peers can fail to set NETRXF_csum_blank when sending a GSO * frame. In this case force the SKB to CHECKSUM_PARTIAL and * recalculate the partial checksum. */ if (skb->ip_summed != CHECKSUM_PARTIAL && skb_is_gso(skb)) { queue->stats.rx_gso_checksum_fixup++; skb->ip_summed = CHECKSUM_PARTIAL; recalculate_partial_csum = true; } /* A non-CHECKSUM_PARTIAL SKB does not require setup. */ if (skb->ip_summed != CHECKSUM_PARTIAL) return 0; return skb_checksum_setup(skb, recalculate_partial_csum); } static bool tx_credit_exceeded(struct xenvif_queue *queue, unsigned size) { u64 now = get_jiffies_64(); u64 next_credit = queue->credit_window_start + msecs_to_jiffies(queue->credit_usec / 1000); /* Timer could already be pending in rare cases. */ if (timer_pending(&queue->credit_timeout)) { queue->rate_limited = true; return true; } /* Passed the point where we can replenish credit? */ if (time_after_eq64(now, next_credit)) { queue->credit_window_start = now; tx_add_credit(queue); } /* Still too big to send right now? Set a callback. */ if (size > queue->remaining_credit) { mod_timer(&queue->credit_timeout, next_credit); queue->credit_window_start = next_credit; queue->rate_limited = true; return true; } return false; } /* No locking is required in xenvif_mcast_add/del() as they are * only ever invoked from NAPI poll. An RCU list is used because * xenvif_mcast_match() is called asynchronously, during start_xmit. */ static int xenvif_mcast_add(struct xenvif *vif, const u8 *addr) { struct xenvif_mcast_addr *mcast; if (vif->fe_mcast_count == XEN_NETBK_MCAST_MAX) { if (net_ratelimit()) netdev_err(vif->dev, "Too many multicast addresses\n"); return -ENOSPC; } mcast = kzalloc(sizeof(*mcast), GFP_ATOMIC); if (!mcast) return -ENOMEM; ether_addr_copy(mcast->addr, addr); list_add_tail_rcu(&mcast->entry, &vif->fe_mcast_addr); vif->fe_mcast_count++; return 0; } static void xenvif_mcast_del(struct xenvif *vif, const u8 *addr) { struct xenvif_mcast_addr *mcast; list_for_each_entry_rcu(mcast, &vif->fe_mcast_addr, entry) { if (ether_addr_equal(addr, mcast->addr)) { --vif->fe_mcast_count; list_del_rcu(&mcast->entry); kfree_rcu(mcast, rcu); break; } } } bool xenvif_mcast_match(struct xenvif *vif, const u8 *addr) { struct xenvif_mcast_addr *mcast; rcu_read_lock(); list_for_each_entry_rcu(mcast, &vif->fe_mcast_addr, entry) { if (ether_addr_equal(addr, mcast->addr)) { rcu_read_unlock(); return true; } } rcu_read_unlock(); return false; } void xenvif_mcast_addr_list_free(struct xenvif *vif) { /* No need for locking or RCU here. NAPI poll and TX queue * are stopped. */ while (!list_empty(&vif->fe_mcast_addr)) { struct xenvif_mcast_addr *mcast; mcast = list_first_entry(&vif->fe_mcast_addr, struct xenvif_mcast_addr, entry); --vif->fe_mcast_count; list_del(&mcast->entry); kfree(mcast); } } static void xenvif_tx_build_gops(struct xenvif_queue *queue, int budget, unsigned *copy_ops, unsigned *map_ops) { struct sk_buff *skb, *nskb; int ret; unsigned int frag_overflow; while (skb_queue_len(&queue->tx_queue) < budget) { struct xen_netif_tx_request txreq; struct xen_netif_tx_request txfrags[XEN_NETBK_LEGACY_SLOTS_MAX]; struct xen_netif_extra_info extras[XEN_NETIF_EXTRA_TYPE_MAX-1]; unsigned int extra_count; RING_IDX idx; int work_to_do; unsigned int data_len; if (queue->tx.sring->req_prod - queue->tx.req_cons > XEN_NETIF_TX_RING_SIZE) { netdev_err(queue->vif->dev, "Impossible number of requests. " "req_prod %d, req_cons %d, size %ld\n", queue->tx.sring->req_prod, queue->tx.req_cons, XEN_NETIF_TX_RING_SIZE); xenvif_fatal_tx_err(queue->vif); break; } work_to_do = XEN_RING_NR_UNCONSUMED_REQUESTS(&queue->tx); if (!work_to_do) break; idx = queue->tx.req_cons; rmb(); /* Ensure that we see the request before we copy it. */ RING_COPY_REQUEST(&queue->tx, idx, &txreq); /* Credit-based scheduling. */ if (txreq.size > queue->remaining_credit && tx_credit_exceeded(queue, txreq.size)) break; queue->remaining_credit -= txreq.size; work_to_do--; queue->tx.req_cons = ++idx; memset(extras, 0, sizeof(extras)); extra_count = 0; if (txreq.flags & XEN_NETTXF_extra_info) { work_to_do = xenvif_get_extras(queue, extras, &extra_count, work_to_do); idx = queue->tx.req_cons; if (unlikely(work_to_do < 0)) break; } if (extras[XEN_NETIF_EXTRA_TYPE_MCAST_ADD - 1].type) { struct xen_netif_extra_info *extra; extra = &extras[XEN_NETIF_EXTRA_TYPE_MCAST_ADD - 1]; ret = xenvif_mcast_add(queue->vif, extra->u.mcast.addr); make_tx_response(queue, &txreq, extra_count, (ret == 0) ? XEN_NETIF_RSP_OKAY : XEN_NETIF_RSP_ERROR); push_tx_responses(queue); continue; } if (extras[XEN_NETIF_EXTRA_TYPE_MCAST_DEL - 1].type) { struct xen_netif_extra_info *extra; extra = &extras[XEN_NETIF_EXTRA_TYPE_MCAST_DEL - 1]; xenvif_mcast_del(queue->vif, extra->u.mcast.addr); make_tx_response(queue, &txreq, extra_count, XEN_NETIF_RSP_OKAY); push_tx_responses(queue); continue; } data_len = (txreq.size > XEN_NETBACK_TX_COPY_LEN) ? XEN_NETBACK_TX_COPY_LEN : txreq.size; ret = xenvif_count_requests(queue, &txreq, extra_count, txfrags, work_to_do); if (unlikely(ret < 0)) break; idx += ret; if (unlikely(txreq.size < ETH_HLEN)) { netdev_dbg(queue->vif->dev, "Bad packet size: %d\n", txreq.size); xenvif_tx_err(queue, &txreq, extra_count, idx); break; } /* No crossing a page as the payload mustn't fragment. */ if (unlikely((txreq.offset + txreq.size) > XEN_PAGE_SIZE)) { netdev_err(queue->vif->dev, "txreq.offset: %u, size: %u, end: %lu\n", txreq.offset, txreq.size, (unsigned long)(txreq.offset&~XEN_PAGE_MASK) + txreq.size); xenvif_fatal_tx_err(queue->vif); break; } if (ret >= XEN_NETBK_LEGACY_SLOTS_MAX - 1 && data_len < txreq.size) data_len = txreq.size; skb = xenvif_alloc_skb(data_len); if (unlikely(skb == NULL)) { netdev_dbg(queue->vif->dev, "Can't allocate a skb in start_xmit.\n"); xenvif_tx_err(queue, &txreq, extra_count, idx); break; } skb_shinfo(skb)->nr_frags = ret; /* At this point shinfo->nr_frags is in fact the number of * slots, which can be as large as XEN_NETBK_LEGACY_SLOTS_MAX. */ frag_overflow = 0; nskb = NULL; if (skb_shinfo(skb)->nr_frags > MAX_SKB_FRAGS) { frag_overflow = skb_shinfo(skb)->nr_frags - MAX_SKB_FRAGS; BUG_ON(frag_overflow > MAX_SKB_FRAGS); skb_shinfo(skb)->nr_frags = MAX_SKB_FRAGS; nskb = xenvif_alloc_skb(0); if (unlikely(nskb == NULL)) { skb_shinfo(skb)->nr_frags = 0; kfree_skb(skb); xenvif_tx_err(queue, &txreq, extra_count, idx); if (net_ratelimit()) netdev_err(queue->vif->dev, "Can't allocate the frag_list skb.\n"); break; } } if (extras[XEN_NETIF_EXTRA_TYPE_GSO - 1].type) { struct xen_netif_extra_info *gso; gso = &extras[XEN_NETIF_EXTRA_TYPE_GSO - 1]; if (xenvif_set_skb_gso(queue->vif, skb, gso)) { /* Failure in xenvif_set_skb_gso is fatal. */ skb_shinfo(skb)->nr_frags = 0; kfree_skb(skb); kfree_skb(nskb); break; } } if (extras[XEN_NETIF_EXTRA_TYPE_HASH - 1].type) { struct xen_netif_extra_info *extra; enum pkt_hash_types type = PKT_HASH_TYPE_NONE; extra = &extras[XEN_NETIF_EXTRA_TYPE_HASH - 1]; switch (extra->u.hash.type) { case _XEN_NETIF_CTRL_HASH_TYPE_IPV4: case _XEN_NETIF_CTRL_HASH_TYPE_IPV6: type = PKT_HASH_TYPE_L3; break; case _XEN_NETIF_CTRL_HASH_TYPE_IPV4_TCP: case _XEN_NETIF_CTRL_HASH_TYPE_IPV6_TCP: type = PKT_HASH_TYPE_L4; break; default: break; } if (type != PKT_HASH_TYPE_NONE) skb_set_hash(skb, *(u32 *)extra->u.hash.value, type); } xenvif_get_requests(queue, skb, &txreq, txfrags, copy_ops, map_ops, frag_overflow, nskb, extra_count, data_len); __skb_queue_tail(&queue->tx_queue, skb); queue->tx.req_cons = idx; if ((*map_ops >= ARRAY_SIZE(queue->tx_map_ops)) || (*copy_ops >= ARRAY_SIZE(queue->tx_copy_ops))) break; } return; } /* Consolidate skb with a frag_list into a brand new one with local pages on * frags. Returns 0 or -ENOMEM if can't allocate new pages. */ static int xenvif_handle_frag_list(struct xenvif_queue *queue, struct sk_buff *skb) { unsigned int offset = skb_headlen(skb); skb_frag_t frags[MAX_SKB_FRAGS]; int i, f; struct ubuf_info *uarg; struct sk_buff *nskb = skb_shinfo(skb)->frag_list; queue->stats.tx_zerocopy_sent += 2; queue->stats.tx_frag_overflow++; xenvif_fill_frags(queue, nskb); /* Subtract frags size, we will correct it later */ skb->truesize -= skb->data_len; skb->len += nskb->len; skb->data_len += nskb->len; /* create a brand new frags array and coalesce there */ for (i = 0; offset < skb->len; i++) { struct page *page; unsigned int len; BUG_ON(i >= MAX_SKB_FRAGS); page = alloc_page(GFP_ATOMIC); if (!page) { int j; skb->truesize += skb->data_len; for (j = 0; j < i; j++) put_page(skb_frag_page(&frags[j])); return -ENOMEM; } if (offset + PAGE_SIZE < skb->len) len = PAGE_SIZE; else len = skb->len - offset; if (skb_copy_bits(skb, offset, page_address(page), len)) BUG(); offset += len; __skb_frag_set_page(&frags[i], page); skb_frag_off_set(&frags[i], 0); skb_frag_size_set(&frags[i], len); } /* Release all the original (foreign) frags. */ for (f = 0; f < skb_shinfo(skb)->nr_frags; f++) skb_frag_unref(skb, f); uarg = skb_shinfo(skb)->destructor_arg; /* increase inflight counter to offset decrement in callback */ atomic_inc(&queue->inflight_packets); uarg->callback(NULL, uarg, true); skb_shinfo(skb)->destructor_arg = NULL; /* Fill the skb with the new (local) frags. */ memcpy(skb_shinfo(skb)->frags, frags, i * sizeof(skb_frag_t)); skb_shinfo(skb)->nr_frags = i; skb->truesize += i * PAGE_SIZE; return 0; } static int xenvif_tx_submit(struct xenvif_queue *queue) { struct gnttab_map_grant_ref *gop_map = queue->tx_map_ops; struct gnttab_copy *gop_copy = queue->tx_copy_ops; struct sk_buff *skb; int work_done = 0; while ((skb = __skb_dequeue(&queue->tx_queue)) != NULL) { struct xen_netif_tx_request *txp; u16 pending_idx; pending_idx = copy_pending_idx(skb, 0); txp = &queue->pending_tx_info[pending_idx].req; /* Check the remap error code. */ if (unlikely(xenvif_tx_check_gop(queue, skb, &gop_map, &gop_copy))) { /* If there was an error, xenvif_tx_check_gop is * expected to release all the frags which were mapped, * so kfree_skb shouldn't do it again */ skb_shinfo(skb)->nr_frags = 0; if (skb_has_frag_list(skb)) { struct sk_buff *nskb = skb_shinfo(skb)->frag_list; skb_shinfo(nskb)->nr_frags = 0; } kfree_skb(skb); continue; } if (txp->flags & XEN_NETTXF_csum_blank) skb->ip_summed = CHECKSUM_PARTIAL; else if (txp->flags & XEN_NETTXF_data_validated) skb->ip_summed = CHECKSUM_UNNECESSARY; xenvif_fill_frags(queue, skb); if (unlikely(skb_has_frag_list(skb))) { struct sk_buff *nskb = skb_shinfo(skb)->frag_list; xenvif_skb_zerocopy_prepare(queue, nskb); if (xenvif_handle_frag_list(queue, skb)) { if (net_ratelimit()) netdev_err(queue->vif->dev, "Not enough memory to consolidate frag_list!\n"); xenvif_skb_zerocopy_prepare(queue, skb); kfree_skb(skb); continue; } /* Copied all the bits from the frag list -- free it. */ skb_frag_list_init(skb); kfree_skb(nskb); } skb->dev = queue->vif->dev; skb->protocol = eth_type_trans(skb, skb->dev); skb_reset_network_header(skb); if (checksum_setup(queue, skb)) { netdev_dbg(queue->vif->dev, "Can't setup checksum in net_tx_action\n"); /* We have to set this flag to trigger the callback */ if (skb_shinfo(skb)->destructor_arg) xenvif_skb_zerocopy_prepare(queue, skb); kfree_skb(skb); continue; } skb_probe_transport_header(skb); /* If the packet is GSO then we will have just set up the * transport header offset in checksum_setup so it's now * straightforward to calculate gso_segs. */ if (skb_is_gso(skb)) { int mss, hdrlen; /* GSO implies having the L4 header. */ WARN_ON_ONCE(!skb_transport_header_was_set(skb)); if (unlikely(!skb_transport_header_was_set(skb))) { kfree_skb(skb); continue; } mss = skb_shinfo(skb)->gso_size; hdrlen = skb_tcp_all_headers(skb); skb_shinfo(skb)->gso_segs = DIV_ROUND_UP(skb->len - hdrlen, mss); } queue->stats.rx_bytes += skb->len; queue->stats.rx_packets++; work_done++; /* Set this flag right before netif_receive_skb, otherwise * someone might think this packet already left netback, and * do a skb_copy_ubufs while we are still in control of the * skb. E.g. the __pskb_pull_tail earlier can do such thing. */ if (skb_shinfo(skb)->destructor_arg) { xenvif_skb_zerocopy_prepare(queue, skb); queue->stats.tx_zerocopy_sent++; } netif_receive_skb(skb); } return work_done; } void xenvif_zerocopy_callback(struct sk_buff *skb, struct ubuf_info *ubuf_base, bool zerocopy_success) { unsigned long flags; pending_ring_idx_t index; struct ubuf_info_msgzc *ubuf = uarg_to_msgzc(ubuf_base); struct xenvif_queue *queue = ubuf_to_queue(ubuf); /* This is the only place where we grab this lock, to protect callbacks * from each other. */ spin_lock_irqsave(&queue->callback_lock, flags); do { u16 pending_idx = ubuf->desc; ubuf = (struct ubuf_info_msgzc *) ubuf->ctx; BUG_ON(queue->dealloc_prod - queue->dealloc_cons >= MAX_PENDING_REQS); index = pending_index(queue->dealloc_prod); queue->dealloc_ring[index] = pending_idx; /* Sync with xenvif_tx_dealloc_action: * insert idx then incr producer. */ smp_wmb(); queue->dealloc_prod++; } while (ubuf); spin_unlock_irqrestore(&queue->callback_lock, flags); if (likely(zerocopy_success)) queue->stats.tx_zerocopy_success++; else queue->stats.tx_zerocopy_fail++; xenvif_skb_zerocopy_complete(queue); } static inline void xenvif_tx_dealloc_action(struct xenvif_queue *queue) { struct gnttab_unmap_grant_ref *gop; pending_ring_idx_t dc, dp; u16 pending_idx, pending_idx_release[MAX_PENDING_REQS]; unsigned int i = 0; dc = queue->dealloc_cons; gop = queue->tx_unmap_ops; /* Free up any grants we have finished using */ do { dp = queue->dealloc_prod; /* Ensure we see all indices enqueued by all * xenvif_zerocopy_callback(). */ smp_rmb(); while (dc != dp) { BUG_ON(gop - queue->tx_unmap_ops >= MAX_PENDING_REQS); pending_idx = queue->dealloc_ring[pending_index(dc++)]; pending_idx_release[gop - queue->tx_unmap_ops] = pending_idx; queue->pages_to_unmap[gop - queue->tx_unmap_ops] = queue->mmap_pages[pending_idx]; gnttab_set_unmap_op(gop, idx_to_kaddr(queue, pending_idx), GNTMAP_host_map, queue->grant_tx_handle[pending_idx]); xenvif_grant_handle_reset(queue, pending_idx); ++gop; } } while (dp != queue->dealloc_prod); queue->dealloc_cons = dc; if (gop - queue->tx_unmap_ops > 0) { int ret; ret = gnttab_unmap_refs(queue->tx_unmap_ops, NULL, queue->pages_to_unmap, gop - queue->tx_unmap_ops); if (ret) { netdev_err(queue->vif->dev, "Unmap fail: nr_ops %tu ret %d\n", gop - queue->tx_unmap_ops, ret); for (i = 0; i < gop - queue->tx_unmap_ops; ++i) { if (gop[i].status != GNTST_okay) netdev_err(queue->vif->dev, " host_addr: 0x%llx handle: 0x%x status: %d\n", gop[i].host_addr, gop[i].handle, gop[i].status); } BUG(); } } for (i = 0; i < gop - queue->tx_unmap_ops; ++i) xenvif_idx_release(queue, pending_idx_release[i], XEN_NETIF_RSP_OKAY); } /* Called after netfront has transmitted */ int xenvif_tx_action(struct xenvif_queue *queue, int budget) { unsigned nr_mops = 0, nr_cops = 0; int work_done, ret; if (unlikely(!tx_work_todo(queue))) return 0; xenvif_tx_build_gops(queue, budget, &nr_cops, &nr_mops); if (nr_cops == 0) return 0; gnttab_batch_copy(queue->tx_copy_ops, nr_cops); if (nr_mops != 0) { ret = gnttab_map_refs(queue->tx_map_ops, NULL, queue->pages_to_map, nr_mops); if (ret) { unsigned int i; netdev_err(queue->vif->dev, "Map fail: nr %u ret %d\n", nr_mops, ret); for (i = 0; i < nr_mops; ++i) WARN_ON_ONCE(queue->tx_map_ops[i].status == GNTST_okay); } } work_done = xenvif_tx_submit(queue); return work_done; } static void xenvif_idx_release(struct xenvif_queue *queue, u16 pending_idx, u8 status) { struct pending_tx_info *pending_tx_info; pending_ring_idx_t index; unsigned long flags; pending_tx_info = &queue->pending_tx_info[pending_idx]; spin_lock_irqsave(&queue->response_lock, flags); make_tx_response(queue, &pending_tx_info->req, pending_tx_info->extra_count, status); /* Release the pending index before pusing the Tx response so * its available before a new Tx request is pushed by the * frontend. */ index = pending_index(queue->pending_prod++); queue->pending_ring[index] = pending_idx; push_tx_responses(queue); spin_unlock_irqrestore(&queue->response_lock, flags); } static void make_tx_response(struct xenvif_queue *queue, struct xen_netif_tx_request *txp, unsigned int extra_count, s8 st) { RING_IDX i = queue->tx.rsp_prod_pvt; struct xen_netif_tx_response *resp; resp = RING_GET_RESPONSE(&queue->tx, i); resp->id = txp->id; resp->status = st; while (extra_count-- != 0) RING_GET_RESPONSE(&queue->tx, ++i)->status = XEN_NETIF_RSP_NULL; queue->tx.rsp_prod_pvt = ++i; } static void push_tx_responses(struct xenvif_queue *queue) { int notify; RING_PUSH_RESPONSES_AND_CHECK_NOTIFY(&queue->tx, notify); if (notify) notify_remote_via_irq(queue->tx_irq); } static void xenvif_idx_unmap(struct xenvif_queue *queue, u16 pending_idx) { int ret; struct gnttab_unmap_grant_ref tx_unmap_op; gnttab_set_unmap_op(&tx_unmap_op, idx_to_kaddr(queue, pending_idx), GNTMAP_host_map, queue->grant_tx_handle[pending_idx]); xenvif_grant_handle_reset(queue, pending_idx); ret = gnttab_unmap_refs(&tx_unmap_op, NULL, &queue->mmap_pages[pending_idx], 1); if (ret) { netdev_err(queue->vif->dev, "Unmap fail: ret: %d pending_idx: %d host_addr: %llx handle: 0x%x status: %d\n", ret, pending_idx, tx_unmap_op.host_addr, tx_unmap_op.handle, tx_unmap_op.status); BUG(); } } static inline int tx_work_todo(struct xenvif_queue *queue) { if (likely(RING_HAS_UNCONSUMED_REQUESTS(&queue->tx))) return 1; return 0; } static inline bool tx_dealloc_work_todo(struct xenvif_queue *queue) { return queue->dealloc_cons != queue->dealloc_prod; } void xenvif_unmap_frontend_data_rings(struct xenvif_queue *queue) { if (queue->tx.sring) xenbus_unmap_ring_vfree(xenvif_to_xenbus_device(queue->vif), queue->tx.sring); if (queue->rx.sring) xenbus_unmap_ring_vfree(xenvif_to_xenbus_device(queue->vif), queue->rx.sring); } int xenvif_map_frontend_data_rings(struct xenvif_queue *queue, grant_ref_t tx_ring_ref, grant_ref_t rx_ring_ref) { void *addr; struct xen_netif_tx_sring *txs; struct xen_netif_rx_sring *rxs; RING_IDX rsp_prod, req_prod; int err; err = xenbus_map_ring_valloc(xenvif_to_xenbus_device(queue->vif), &tx_ring_ref, 1, &addr); if (err) goto err; txs = (struct xen_netif_tx_sring *)addr; rsp_prod = READ_ONCE(txs->rsp_prod); req_prod = READ_ONCE(txs->req_prod); BACK_RING_ATTACH(&queue->tx, txs, rsp_prod, XEN_PAGE_SIZE); err = -EIO; if (req_prod - rsp_prod > RING_SIZE(&queue->tx)) goto err; err = xenbus_map_ring_valloc(xenvif_to_xenbus_device(queue->vif), &rx_ring_ref, 1, &addr); if (err) goto err; rxs = (struct xen_netif_rx_sring *)addr; rsp_prod = READ_ONCE(rxs->rsp_prod); req_prod = READ_ONCE(rxs->req_prod); BACK_RING_ATTACH(&queue->rx, rxs, rsp_prod, XEN_PAGE_SIZE); err = -EIO; if (req_prod - rsp_prod > RING_SIZE(&queue->rx)) goto err; return 0; err: xenvif_unmap_frontend_data_rings(queue); return err; } static bool xenvif_dealloc_kthread_should_stop(struct xenvif_queue *queue) { /* Dealloc thread must remain running until all inflight * packets complete. */ return kthread_should_stop() && !atomic_read(&queue->inflight_packets); } int xenvif_dealloc_kthread(void *data) { struct xenvif_queue *queue = data; for (;;) { wait_event_interruptible(queue->dealloc_wq, tx_dealloc_work_todo(queue) || xenvif_dealloc_kthread_should_stop(queue)); if (xenvif_dealloc_kthread_should_stop(queue)) break; xenvif_tx_dealloc_action(queue); cond_resched(); } /* Unmap anything remaining*/ if (tx_dealloc_work_todo(queue)) xenvif_tx_dealloc_action(queue); return 0; } static void make_ctrl_response(struct xenvif *vif, const struct xen_netif_ctrl_request *req, u32 status, u32 data) { RING_IDX idx = vif->ctrl.rsp_prod_pvt; struct xen_netif_ctrl_response rsp = { .id = req->id, .type = req->type, .status = status, .data = data, }; *RING_GET_RESPONSE(&vif->ctrl, idx) = rsp; vif->ctrl.rsp_prod_pvt = ++idx; } static void push_ctrl_response(struct xenvif *vif) { int notify; RING_PUSH_RESPONSES_AND_CHECK_NOTIFY(&vif->ctrl, notify); if (notify) notify_remote_via_irq(vif->ctrl_irq); } static void process_ctrl_request(struct xenvif *vif, const struct xen_netif_ctrl_request *req) { u32 status = XEN_NETIF_CTRL_STATUS_NOT_SUPPORTED; u32 data = 0; switch (req->type) { case XEN_NETIF_CTRL_TYPE_SET_HASH_ALGORITHM: status = xenvif_set_hash_alg(vif, req->data[0]); break; case XEN_NETIF_CTRL_TYPE_GET_HASH_FLAGS: status = xenvif_get_hash_flags(vif, &data); break; case XEN_NETIF_CTRL_TYPE_SET_HASH_FLAGS: status = xenvif_set_hash_flags(vif, req->data[0]); break; case XEN_NETIF_CTRL_TYPE_SET_HASH_KEY: status = xenvif_set_hash_key(vif, req->data[0], req->data[1]); break; case XEN_NETIF_CTRL_TYPE_GET_HASH_MAPPING_SIZE: status = XEN_NETIF_CTRL_STATUS_SUCCESS; data = XEN_NETBK_MAX_HASH_MAPPING_SIZE; break; case XEN_NETIF_CTRL_TYPE_SET_HASH_MAPPING_SIZE: status = xenvif_set_hash_mapping_size(vif, req->data[0]); break; case XEN_NETIF_CTRL_TYPE_SET_HASH_MAPPING: status = xenvif_set_hash_mapping(vif, req->data[0], req->data[1], req->data[2]); break; default: break; } make_ctrl_response(vif, req, status, data); push_ctrl_response(vif); } static void xenvif_ctrl_action(struct xenvif *vif) { for (;;) { RING_IDX req_prod, req_cons; req_prod = vif->ctrl.sring->req_prod; req_cons = vif->ctrl.req_cons; /* Make sure we can see requests before we process them. */ rmb(); if (req_cons == req_prod) break; while (req_cons != req_prod) { struct xen_netif_ctrl_request req; RING_COPY_REQUEST(&vif->ctrl, req_cons, &req); req_cons++; process_ctrl_request(vif, &req); } vif->ctrl.req_cons = req_cons; vif->ctrl.sring->req_event = req_cons + 1; } } static bool xenvif_ctrl_work_todo(struct xenvif *vif) { if (likely(RING_HAS_UNCONSUMED_REQUESTS(&vif->ctrl))) return true; return false; } irqreturn_t xenvif_ctrl_irq_fn(int irq, void *data) { struct xenvif *vif = data; unsigned int eoi_flag = XEN_EOI_FLAG_SPURIOUS; while (xenvif_ctrl_work_todo(vif)) { xenvif_ctrl_action(vif); eoi_flag = 0; } xen_irq_lateeoi(irq, eoi_flag); return IRQ_HANDLED; } static int __init netback_init(void) { int rc = 0; if (!xen_domain()) return -ENODEV; /* Allow as many queues as there are CPUs but max. 8 if user has not * specified a value. */ if (xenvif_max_queues == 0) xenvif_max_queues = min_t(unsigned int, MAX_QUEUES_DEFAULT, num_online_cpus()); if (fatal_skb_slots < XEN_NETBK_LEGACY_SLOTS_MAX) { pr_info("fatal_skb_slots too small (%d), bump it to XEN_NETBK_LEGACY_SLOTS_MAX (%d)\n", fatal_skb_slots, XEN_NETBK_LEGACY_SLOTS_MAX); fatal_skb_slots = XEN_NETBK_LEGACY_SLOTS_MAX; } rc = xenvif_xenbus_init(); if (rc) goto failed_init; #ifdef CONFIG_DEBUG_FS xen_netback_dbg_root = debugfs_create_dir("xen-netback", NULL); #endif /* CONFIG_DEBUG_FS */ return 0; failed_init: return rc; } module_init(netback_init); static void __exit netback_fini(void) { #ifdef CONFIG_DEBUG_FS debugfs_remove_recursive(xen_netback_dbg_root); #endif /* CONFIG_DEBUG_FS */ xenvif_xenbus_fini(); } module_exit(netback_fini); MODULE_LICENSE("Dual BSD/GPL"); MODULE_ALIAS("xen-backend:vif");
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
1663
1664
1665
1666
1667
1668
1669
1670
1671
1672
1673
1674
1675
1676
1677
1678
1679
1680
1681
1682
1683
1684
1685
1686
1687
1688
1689
1690
1691
1692
1693
1694
1695
1696
1697
1698
1699
1700
1701
1702
1703
1704
1705
1706
1707
1708
1709
1710
1711
1712
1713
1714
1715
1716
1717
1718
1719
1720
1721
1722
1723
1724
1725
1726
1727
1728
1729
1730
1731
1732
1733
1734
1735
1736
You can’t perform that action at this time.