lwn.git/drivers/net/xen-netback/netback.c, branch v4.3-rc3

Merge tag 'for-linus-4.3-rc0b-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip

2015-09-10T23:21:11+00:00

Pull xen terminology fixes from David Vrabel: "Use the correct GFN/BFN terms more consistently" * tag 'for-linus-4.3-rc0b-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: xen/xenbus: Rename the variable xen_store_mfn to xen_store_gfn xen/privcmd: Further s/MFN/GFN/ clean-up hvc/xen: Further s/MFN/GFN clean-up video/xen-fbfront: Further s/MFN/GFN clean-up xen/tmem: Use xen_page_to_gfn rather than pfn_to_gfn xen: Use correctly the Xen memory terminologies arm/xen: implement correctly pfn_to_mfn xen: Make clear that swiotlb and biomerge are dealing with DMA address

xen-netback: respect user provided max_queues

2015-09-10T17:11:48+00:00

Originally that parameter was always reset to num_online_cpus during module initialisation, which renders it useless. The fix is to only set max_queues to num_online_cpus when user has not provided a value. Reported-by: Johnny Strom Signed-off-by: Wei Liu Reviewed-by: David Vrabel Acked-by: Ian Campbell Signed-off-by: David S. Miller

xen-netback: require fewer guest Rx slots when not using GSO

2015-09-09T19:34:35+00:00

Commit f48da8b14d04ca87ffcffe68829afd45f926ec6a (xen-netback: fix unlimited guest Rx internal queue and carrier flapping) introduced a regression. The PV frontend in IPXE only places 4 requests on the guest Rx ring. Since netback required at least (MAX_SKB_FRAGS + 1) slots, IPXE could not receive any packets. a) If GSO is not enabled on the VIF, fewer guest Rx slots are required for the largest possible packet. Calculate the required slots based on the maximum GSO size or the MTU. This calculation of the number of required slots relies on 1650d5455bd2 (xen-netback: always fully coalesce guest Rx packets) which present in 4.0-rc1 and later. b) Reduce the Rx stall detection to checking for at least one available Rx request. This is fine since we're predominately concerned with detecting interfaces which are down and thus have zero available Rx requests. Signed-off-by: David Vrabel Reviewed-by: Wei Liu Signed-off-by: David S. Miller

xen: Use correctly the Xen memory terminologies

2015-09-08T17:03:49+00:00

Based on include/xen/mm.h [1], Linux is mistakenly using MFN when GFN is meant, I suspect this is because the first support for Xen was for PV. This resulted in some misimplementation of helpers on ARM and confused developers about the expected behavior. For instance, with pfn_to_mfn, we expect to get an MFN based on the name. Although, if we look at the implementation on x86, it's returning a GFN. For clarity and avoid new confusion, replace any reference to mfn with gfn in any helpers used by PV drivers. The x86 code will still keep some reference of pfn_to_mfn which may be used by all kind of guests No changes as been made in the hypercall field, even though they may be invalid, in order to keep the same as the defintion in xen repo. Note that page_to_mfn has been renamed to xen_page_to_gfn to avoid a name to close to the KVM function gfn_to_page. Take also the opportunity to simplify simple construction such as pfn_to_mfn(page_to_pfn(page)) into xen_page_to_gfn. More complex clean up will come in follow-up patches. [1] http://xenbits.xen.org/gitweb/?p=xen.git;a=commitdiff;h=e758ed14f390342513405dd766e874934573e6cb Signed-off-by: Julien Grall Reviewed-by: Stefano Stabellini Acked-by: Dmitry Torokhov Acked-by: Wei Liu Signed-off-by: David Vrabel

xen-netback: add support for multicast control

2015-09-02T18:45:00+00:00

Xen's PV network protocol includes messages to add/remove ethernet multicast addresses to/from a filter list in the backend. This allows the frontend to request the backend only forward multicast packets which are of interest thus preventing unnecessary noise on the shared ring. The canonical netif header in git://xenbits.xen.org/xen.git specifies the message format (two more XEN_NETIF_EXTRA_TYPEs) so the minimal necessary changes have been pulled into include/xen/interface/io/netif.h. To prevent the frontend from extending the multicast filter list arbitrarily a limit (XEN_NETBK_MCAST_MAX) has been set to 64 entries. This limit is not specified by the protocol and so may change in future. If the limit is reached then the next XEN_NETIF_EXTRA_TYPE_MCAST_ADD sent by the frontend will be failed with NETIF_RSP_ERROR. Signed-off-by: Paul Durrant Cc: Ian Campbell Cc: Wei Liu Acked-by: Wei Liu Signed-off-by: David S. Miller

xen/netback: Wake dealloc thread after completing zerocopy work

2015-08-07T06:42:48+00:00

Waking the dealloc thread before decrementing inflight_packets is racy because it means the thread may go to sleep before inflight_packets is decremented. If kthread_stop() has already been called, the dealloc thread may wait forever with nothing to wake it. Instead, wake the thread only after decrementing inflight_packets. Signed-off-by: Ross Lagerwall Signed-off-by: David S. Miller

xen-netback: Allocate fraglist early to avoid complex rollback

2015-08-04T05:23:03+00:00

Determine if a fraglist is needed in the tx path, and allocate it if necessary before setting up the copy and map operations. Otherwise, undoing the copy and map operations is tricky. This fixes a use-after-free: if allocating the fraglist failed, the copy and map operations that had been set up were still executed, writing over the data area of a freed skb. Signed-off-by: Ross Lagerwall Signed-off-by: David S. Miller

net/xen-netback: off by one in BUG_ON() condition

2015-07-14T22:40:52+00:00

The > should be >=. I also added spaces around the '-' operations so the code is a little more consistent and matches the condition better. Fixes: f53c3fe8dad7 ('xen-netback: Introduce TX grant mapping') Signed-off-by: Dan Carpenter Signed-off-by: David S. Miller

Merge tag 'for-linus-4.2-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip

2015-07-01T18:53:46+00:00

Pull xen updates from David Vrabel: "Xen features and cleanups for 4.2-rc0: - add "make xenconfig" to assist in generating configs for Xen guests - preparatory cleanups necessary for supporting 64 KiB pages in ARM guests - automatically use hvc0 as the default console in ARM guests" * tag 'for-linus-4.2-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: block/xen-blkback: s/nr_pages/nr_segs/ block/xen-blkfront: Remove invalid comment block/xen-blkfront: Remove unused macro MAXIMUM_OUTSTANDING_BLOCK_REQS arm/xen: Drop duplicate define mfn_to_virt xen/grant-table: Remove unused macro SPP xen/xenbus: client: Fix call of virt_to_mfn in xenbus_grant_ring xen: Include xen/page.h rather than asm/xen/page.h kconfig: add xenconfig defconfig helper kconfig: clarify kvmconfig is for kvm xen/pcifront: Remove usage of struct timeval xen/tmem: use BUILD_BUG_ON() in favor of BUG_ON() hvc_xen: avoid uninitialized variable warning xenbus: avoid uninitialized variable warning xen/arm: allow console=hvc0 to be omitted for guests arm,arm64/xen: move Xen initialization earlier arm/xen: Correctly check if the event channel interrupt is present

net/xen-netback: Don't mix hexa and decimal with 0x in the printf format

2015-06-21T16:40:41+00:00

Append 0x to all %x in order to avoid while reading when there is other decimal value in the log. Also replace some of the hexadecimal print to decimal to uniformize the format with netfront. Signed-off-by: Julien Grall Cc: Wei Liu Cc: Ian Campbell Cc: netdev@vger.kernel.org Acked-by: Ian Campbell Signed-off-by: David S. Miller