1. 14 Oct, 2016 20 commits
    • Brenden Blanco's avatar
      net/mlx4_en: fixup xdp tx irq to match rx · 958b3d39
      Brenden Blanco authored
      In cases where the number of tx rings is not a multiple of the number of
      rx rings, the tx completion event will be handled on a different core
      from the transmit and population of the ring. Races on the ring will
      lead to a double-free of the page, and possibly other corruption.
      
      The rings are initialized by default with a valid multiple of rings,
      based on the number of cpus, therefore an invalid configuration requires
      ethtool to change the ring layout. For instance 'ethtool -L eth0 rx 9 tx
      8' will cause packets received on rx0, and XDP_TX'd to tx48, to be
      completed on cpu3 (48 % 9 == 3).
      
      Resolve this discrepancy by shifting the irq for the xdp tx queues to
      start again from 0, modulo rx_ring_num.
      
      Fixes: 9ecc2d86
      
       ("net/mlx4_en: add xdp forwarding and data write support")
      Reported-by: default avatarJesper Dangaard Brouer <brouer@redhat.com>
      Signed-off-by: default avatarBrenden Blanco <bblanco@plumgrid.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      958b3d39
    • David S. Miller's avatar
      Merge branch 'qed-fixes' · fbbfa34c
      David S. Miller authored
      
      
      Yuval Mintz says:
      
      ====================
      qed: Fix dependencies and warnings series
      
      The first patch in this series follows Dan Carpenter's reports about
      Smatch warnings for recent qed additions and fixes those.
      
      The second patch is the most significant one [and the reason this is
      ntended for 'net'] - it's based on Arnd Bermann's suggestion for fixing
      compilation issues that were introduced with the roce addition as a result
      of certain combinations of qed, qede and qedr Kconfig options.
      
      The third follows the discussion with Arnd and clears a lot of the warnings
      that arise when compiling the drivers with "C=1".
      
      Please consider applying this series to 'net'.
      ====================
      
      Acked-by: default avatarArnd Bergmann <arnd@arndb.de>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      fbbfa34c
    • Yuval Mintz's avatar
      qed: Additional work toward cleaning C=1 · 8c93beaf
      Yuval Mintz authored
      
      
      This cleans many of the warnings that would arise in qed as a
      result of compilations with C=1; Most of those are the addition
      of missing 'static' to functions, although there are several other
      fixes as well.
      
      Signed-off-by: default avatarYuval Mintz <Yuval.Mintz@caviumnetworks.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      8c93beaf
    • Yuval Mintz's avatar
      qed*: Fix Kconfig dependencies with INFINIBAND_QEDR · 0189efb8
      Yuval Mintz authored
      The qedr driver would require a tristate Kconfig option [to allow
      it to compile as a module], and toward that end we've added the
      INFINIBAND_QEDR option. But as we've made the compilation of the
      qed/qede infrastructure required for RoCE dependent on the option
      we'd be facing linking difficulties in case that QED=y or QEDE=y,
      and INFINIBAND_QEDR=m.
      
      To resolve this, we seperate between the INFINIBAND_QEDR option
      and the infrastructure support in qed/qede by introducing a new
      QED_RDMA option which would be selected by INFINIBAND_QEDR but would
      be a boolean instead of a tristate; Following that, the qed/qede is
      fixed based on this new option so that all config combinations would
      be supported.
      
      Fixes: cee9fbd8
      
       ("qede: add qedr framework")
      Reported-by: default avatarArnd Bergmann <arnd@arndb.de>
      Signed-off-by: default avatarYuval Mintz <Yuval.Mintz@caviumnetworks.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      0189efb8
    • Yuval Mintz's avatar
      qed: Fix static checker warning. · ce6b04ee
      Yuval Mintz authored
      
      
      Smatch compains about qed_roce_ll2_tx() dereference
      of the 'cdev' variable while testing its validity later.
      As the validation checking is an over-kill [variable would always
      be set], simply remove it.
      
      Reported-by: default avatarDan Carpenter <dan.carpenter@oracle.com>
      Fixes: abd49676
      
       ("qed: Add RoCE ll2 & GSI support")
      Signed-off-by: default avatarYuval Mintz <Yuval.Mintz@caviumnetworks.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      ce6b04ee
    • Jiri Bohac's avatar
      IPv6: fix DESYNC_FACTOR · 76506a98
      Jiri Bohac authored
      The IPv6 temporary address generation uses a variable called DESYNC_FACTOR
      to prevent hosts updating the addresses at the same time. Quoting RFC 4941:
      
         ... The value DESYNC_FACTOR is a random value (different for each
         client) that ensures that clients don't synchronize with each other and
         generate new addresses at exactly the same time ...
      
      DESYNC_FACTOR is defined as:
      
         DESYNC_FACTOR -- A random value within the range 0 - MAX_DESYNC_FACTOR.
         It is computed once at system start (rather than each time it is used)
         and must never be greater than (TEMP_VALID_LIFETIME - REGEN_ADVANCE).
      
      First, I believe the RFC has a typo in it and meant to say: "and must
      never be greater than (TEMP_PREFERRED_LIFETIME - REGEN_ADVANCE)"
      
      The reason is that at various places in the RFC, DESYNC_FACTOR is used in
      a calculation like (TEMP_PREFERRED_LIFETIME - DESYNC_FACTOR) or
      (TEMP_PREFERRED_LIFETIME - REGEN_ADVANCE - DESYNC_FACTOR). It needs to be
      smaller than (TEMP_PREFERRED_LIFETIME - REGEN_ADVANCE) for the result of
      these calculations to be larger than zero. It's never used in a
      calculation together with TEMP_VALID_LIFETIME.
      
      I already submitted an errata to the rfc-editor:
      https://www.rfc-editor.org/errata_search.php?rfc=4941
      
      
      
      The Linux implementation of DESYNC_FACTOR is very wrong:
      max_desync_factor is used in places DESYNC_FACTOR should be used.
      max_desync_factor is initialized to the RFC-recommended value for
      MAX_DESYNC_FACTOR (600) but the whole point is to get a _random_ value.
      
      And nothing ensures that the value used is not greater than
      (TEMP_PREFERRED_LIFETIME - REGEN_ADVANCE), which leads to underflows.  The
      effect can easily be observed when setting the temp_prefered_lft sysctl
      e.g. to 60. The preferred lifetime of the temporary addresses will be
      bogus.
      
      TEMP_PREFERRED_LIFETIME and REGEN_ADVANCE are not constants and can be
      influenced by these three sysctls: regen_max_retry, dad_transmits and
      temp_prefered_lft. Thus, the upper bound for desync_factor needs to be
      re-calculated each time a new address is generated and if desync_factor is
      larger than the new upper bound, a new random value needs to be
      re-generated.
      
      And since we already have max_desync_factor configurable per interface, we
      also need to calculate and store desync_factor per interface.
      
      Signed-off-by: default avatarJiri Bohac <jbohac@suse.cz>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      76506a98
    • Jiri Bohac's avatar
      IPv6: Drop the temporary address regen_timer · 9d6280da
      Jiri Bohac authored
      
      
      The randomized interface identifier (rndid) was periodically updated from
      the regen_timer timer. Simplify the code by updating the rndid only when
      needed by ipv6_try_regen_rndid().
      
      This makes the follow-up DESYNC_FACTOR fix much simpler.  Also it fixes a
      reference counting error in this error path, where an in6_dev_put was
      missing:
      		err = addrconf_sysctl_register(ndev);
      		if (err) {
      			ipv6_mc_destroy_dev(ndev);
      	-               del_timer(&ndev->regen_timer);
      			snmp6_unregister_dev(ndev);
      			goto err_release;
      
      Signed-off-by: default avatarJiri Bohac <jbohac@suse.cz>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      9d6280da
    • Paolo Abeni's avatar
      IB/ipoib: move back IB LL address into the hard header · fc791b63
      Paolo Abeni authored
      After the commit 9207f9d4 ("net: preserve IP control block
      during GSO segmentation"), the GSO CB and the IPoIB CB conflict.
      That destroy the IPoIB address information cached there,
      causing a severe performance regression, as better described here:
      
      http://marc.info/?l=linux-kernel&m=146787279825501&w=2
      
      This change moves the data cached by the IPoIB driver from the
      skb control lock into the IPoIB hard header, as done before
      the commit 936d7de3 ("IPoIB: Stop lying about hard_header_len
      and use skb->cb to stash LL addresses").
      In order to avoid GRO issue, on packet reception, the IPoIB driver
      stash into the skb a dummy pseudo header, so that the received
      packets have actually a hard header matching the declared length.
      To avoid changing the connected mode maximum mtu, the allocated
      head buffer size is increased by the pseudo header length.
      
      After this commit, IPoIB performances are back to pre-regression
      value.
      
      v2 -> v3: rebased
      v1 -> v2: avoid changing the max mtu, increasing the head buf size
      
      Fixes: 9207f9d4
      
       ("net: preserve IP control block during GSO segmentation")
      Signed-off-by: default avatarPaolo Abeni <pabeni@redhat.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      fc791b63
    • David S. Miller's avatar
      Merge tag 'rxrpc-rewrite-20161013' of... · f1f081ce
      David S. Miller authored
      Merge tag 'rxrpc-rewrite-20161013' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs
      
      
      
      David Howells says:
      
      ====================
      rxrpc: Fixes
      
      This set of patches contains a bunch of fixes:
      
       (1) Fix use of kunmap() after change from kunmap_atomic() within AFS.
      
       (2) Don't use of ERR_PTR() with an always zero value.
      
       (3) Check the right error when using ip6_route_output().
      
       (4) Be consistent about whether call->operation_ID is BE or CPU-E within
           AFS.
      ====================
      
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      f1f081ce
    • Alexander Alemayhu's avatar
      Documentation/networking: update git urls to use https over http · f56f7d2e
      Alexander Alemayhu authored
      This fixes the following errors when trying to clone the urls:
      
      Cloning into 'net'...
      fatal: repository 'http://git.kernel.org/cgit/linux/kernel/git/davem/net.git/' not found
      Cloning into 'net-next'...
      fatal: repository 'http://git.kernel.org/cgit/linux/kernel/git/davem/net-next.git/' not found
      Cloning into 'linux'...
      fatal: repository 'http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/' not found
      Cloning into 'stable-queue'...
      fatal: repository 'http://git.kernel.org/cgit/linux/kernel/git/stable/stable-queue.git/
      
      ' not found
      
      Signed-off-by: default avatarAlexander Alemayhu <alexander@alemayhu.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      f56f7d2e
    • Javier Martinez Canillas's avatar
      net: wan: slic_ds26522: Allow driver to built if COMPILE_TEST is enabled · 059f0141
      Javier Martinez Canillas authored
      
      
      The driver only has runtime but no build time dependency with FSL_SOC ||
      ARCH_MXC || ARCH_LAYERSCAPE.  So it can be built for testing purposes if
      the COMPILE_TEST option is enabled.
      
      This is useful to have more build coverage and make sure that the driver
      is not affected by changes that could cause build regressions.
      
      Signed-off-by: default avatarJavier Martinez Canillas <javier@osg.samsung.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      059f0141
    • Javier Martinez Canillas's avatar
      net: wan: slic_ds26522: Export OF module alias information · 485c9d43
      Javier Martinez Canillas authored
      
      
      When the device is registered via OF, the OF table is used to match the
      driver instead of the SPI device ID table, but the entries in the later
      are used as aliasses to load the module if the driver was not built-in.
      
      This is because the SPI core always reports an SPI module alias instead
      of an OF one, but that could change so it's better to always export it.
      
      Signed-off-by: default avatarJavier Martinez Canillas <javier@osg.samsung.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      485c9d43
    • Javier Martinez Canillas's avatar
      net: wan: slic_ds26522: add SPI device ID table to fix module autoload · 558c5eb5
      Javier Martinez Canillas authored
      
      
      If the driver is built as a module, module alias information isn't filled
      so the module won't be autoloaded. Add a SPI device ID table and use the
      MODULE_DEVICE_TABLE() macro so the information is exported in the module.
      
      Before this patch:
      
      $ modinfo drivers/net/wan/slic_ds26522.ko | grep alias
      $
      
      After this patch:
      
      $ modinfo drivers/net/wan/slic_ds26522.ko | grep alias
      alias:          spi:ds26522
      
      Signed-off-by: default avatarJavier Martinez Canillas <javier@osg.samsung.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      558c5eb5
    • Nicolas Dichtel's avatar
      ipv6: correctly add local routes when lo goes up · a220445f
      Nicolas Dichtel authored
      The goal of the patch is to fix this scenario:
       ip link add dummy1 type dummy
       ip link set dummy1 up
       ip link set lo down ; ip link set lo up
      
      After that sequence, the local route to the link layer address of dummy1 is
      not there anymore.
      
      When the loopback is set down, all local routes are deleted by
      addrconf_ifdown()/rt6_ifdown(). At this time, the rt6_info entry still
      exists, because the corresponding idev has a reference on it. After the rcu
      grace period, dst_rcu_free() is called, and thus ___dst_free(), which will
      set obsolete to DST_OBSOLETE_DEAD.
      
      In this case, init_loopback() is called before dst_rcu_free(), thus
      obsolete is still sets to something <= 0. So, the function doesn't add the
      route again. To avoid that race, let's check the rt6 refcnt instead.
      
      Fixes: 25fb6ca4 ("net IPv6 : Fix broken IPv6 routing table after loopback down-up")
      Fixes: a881ae1f ("ipv6: don't call addrconf_dst_alloc again when enable lo")
      Fixes: 33d99113
      
       ("ipv6: reallocate addrconf router for ipv6 address when lo device up")
      Reported-by: default avatarFrancesco Santoro <francesco.santoro@6wind.com>
      Reported-by: default avatarSamuel Gauthier <samuel.gauthier@6wind.com>
      CC: Balakumaran Kannan <Balakumaran.Kannan@ap.sony.com>
      CC: Maruthi Thotad <Maruthi.Thotad@ap.sony.com>
      CC: Sabrina Dubroca <sd@queasysnail.net>
      CC: Hannes Frederic Sowa <hannes@stressinduktion.org>
      CC: Weilong Chen <chenweilong@huawei.com>
      CC: Gao feng <gaofeng@cn.fujitsu.com>
      Signed-off-by: default avatarNicolas Dichtel <nicolas.dichtel@6wind.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      a220445f
    • Vadim Fedorenko's avatar
      ip6_tunnel: fix ip6_tnl_lookup · 68d00f33
      Vadim Fedorenko authored
      The commit ea3dc960 ("ip6_tunnel: Add support for wildcard tunnel
      endpoints.") introduces support for wildcards in tunnels endpoints,
      but in some rare circumstances ip6_tnl_lookup selects wrong tunnel
      interface relying only on source or destination address of the packet
      and not checking presence of wildcard in tunnels endpoints. Later in
      ip6_tnl_rcv this packets can be dicarded because of difference in
      ipproto even if fallback device have proper ipproto configuration.
      
      This patch adds checks of wildcard endpoint in tunnel avoiding such
      behavior
      
      Fixes: ea3dc960
      
       ("ip6_tunnel: Add support for wildcard tunnel endpoints.")
      Signed-off-by: default avatarVadim Fedorenko <junk@yandex-team.ru>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      68d00f33
    • Linus Torvalds's avatar
      Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net · 29fbff86
      Linus Torvalds authored
      Pull networking fixes from David Miller:
      
       1) Fix various build warnings in tlan/qed/xen-netback drivers, from
          Arnd Bergmann.
      
       2) Propagate proper error code in strparser's strp_recv(), from Geert
          Uytterhoeven.
      
       3) Fix accidental broadcast of RTM_GETTFILTER responses, from Eric
          Dumazret.
      
       4) Need to use list_for_each_entry_safe() in qed driver, from Wei
          Yongjun.
      
       5) Openvswitch 802.1AD bug fixes from Jiri Benc.
      
       6) Cure BUILD_BUG_ON() in mlx5 driver, from Tom Herbert.
      
       7) Fix UDP ipv6 checksumming in netvsc driver, from Stephen Hemminger.
      
       8) stmmac driver fixes from Giuseppe CAVALLARO.
      
       9) Fix access to mangled IP6CB in tcp, from Eric Dumazet.
      
      10) Fix info leaks in tipc and rtnetlink, from Dan Carpenter.
      
      * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (27 commits)
        net: bridge: add the multicast_flood flag attribute to brport_attrs
        net: axienet: Remove unused parameter from __axienet_device_reset
        liquidio: CN23XX: fix a loop timeout
        net: rtnl: info leak in rtnl_fill_vfinfo()
        tipc: info leak in __tipc_nl_add_udp_addr()
        net: ipv4: Do not drop to make_route if oif is l3mdev
        net: phy: Trigger state machine on state change and not polling.
        ipv6: tcp: restore IP6CB for pktoptions skbs
        netvsc: Remove mistaken udp.h inclusion.
        xen-netback: fix type mismatch warning
        stmmac: fix error check when init ptp
        stmmac: fix ptp init for gmac4
        qed: fix old-style function definition
        netvsc: fix checksum on UDP IPV6
        net_sched: reorder pernet ops and act ops registrations
        xen-netback: fix guest Rx stall detection (after guest Rx refactor)
        drivers/ptp: Fix kernel memory disclosure
        net/mlx5: Add MLX5_ARRAY_SET64 to fix BUILD_BUG_ON
        qmi_wwan: add support for Quectel EC21 and EC25
        openvswitch: add NETIF_F_HW_VLAN_STAG_TX to internal dev
        ...
      29fbff86
    • Linus Torvalds's avatar
      Merge tag 'nfs-for-4.9-1' of git://git.linux-nfs.org/projects/anna/linux-nfs · c4a86165
      Linus Torvalds authored
      Pull NFS client updates from Anna Schumaker:
       "Highlights include:
      
        Stable bugfixes:
         - sunrpc: fix writ espace race causing stalls
         - NFS: Fix inode corruption in nfs_prime_dcache()
         - NFSv4: Don't report revoked delegations as valid in nfs_have_delegation()
         - NFSv4: nfs4_copy_delegation_stateid() must fail if the delegation is invalid
         - NFSv4: Open state recovery must account for file permission changes
         - NFSv4.2: Fix a reference leak in nfs42_proc_layoutstats_generic
      
        Features:
         - Add support for tracking multiple layout types with an ordered list
         - Add support for using multiple backchannel threads on the client
         - Add support for pNFS file layout session trunking
         - Delay xprtrdma use of DMA API (for device driver removal)
         - Add support for xprtrdma remote invalidation
         - Add support for larger xprtrdma inline thresholds
         - Use a scatter/gather list for sending xprtrdma RPC calls
         - Add support for the CB_NOTIFY_LOCK callback
         - Improve hashing sunrpc auth_creds by using both uid and gid
      
        Bugfixes:
         - Fix xprtrdma use of DMA API
         - Validate filenames before adding to the dcache
         - Fix corruption of xdr->nwords in xdr_copy_to_scratch
         - Fix setting buffer length in xdr_set_next_buffer()
         - Don't deadlock the state manager on the SEQUENCE status flags
         - Various delegation and stateid related fixes
         - Retry operations if an interrupted slot receives EREMOTEIO
         - Make nfs boot time y2038 safe"
      
      * tag 'nfs-for-4.9-1' of git://git.linux-nfs.org/projects/anna/linux-nfs: (100 commits)
        NFSv4.2: Fix a reference leak in nfs42_proc_layoutstats_generic
        fs: nfs: Make nfs boot time y2038 safe
        sunrpc: replace generic auth_cred hash with auth-specific function
        sunrpc: add RPCSEC_GSS hash_cred() function
        sunrpc: add auth_unix hash_cred() function
        sunrpc: add generic_auth hash_cred() function
        sunrpc: add hash_cred() function to rpc_authops struct
        Retry operation on EREMOTEIO on an interrupted slot
        pNFS: Fix atime updates on pNFS clients
        sunrpc: queue work on system_power_efficient_wq
        NFSv4.1: Even if the stateid is OK, we may need to recover the open modes
        NFSv4: If recovery failed for a specific open stateid, then don't retry
        NFSv4: Fix retry issues with nfs41_test/free_stateid
        NFSv4: Open state recovery must account for file permission changes
        NFSv4: Mark the lock and open stateids as invalid after freeing them
        NFSv4: Don't test open_stateid unless it is set
        NFSv4: nfs4_do_handle_exception() handle revoke/expiry of a single stateid
        NFS: Always call nfs_inode_find_state_and_recover() when revoking a delegation
        NFSv4: Fix a race when updating an open_stateid
        NFSv4: Fix a race in nfs_inode_reclaim_delegation()
        ...
      c4a86165
    • Linus Torvalds's avatar
      Merge tag 'nfsd-4.9' of git://linux-nfs.org/~bfields/linux · 27785564
      Linus Torvalds authored
      Pull nfsd updates from Bruce Fields:
       "Some RDMA work and some good bugfixes, and two new features that could
        benefit from user testing:
      
         - Anna Schumacker contributed a simple NFSv4.2 COPY implementation.
           COPY is already supported on the client side, so a call to
           copy_file_range() on a recent client should now result in a
           server-side copy that doesn't require all the data to make a round
           trip to the client and back.
      
         - Jeff Layton implemented callbacks to notify clients when contended
           locks become available, which should reduce latency on workloads
           with contended locks"
      
      * tag 'nfsd-4.9' of git://linux-nfs.org/~bfields/linux:
        NFSD: Implement the COPY call
        nfsd: handle EUCLEAN
        nfsd: only WARN once on unmapped errors
        exportfs: be careful to only return expected errors.
        nfsd4: setclientid_confirm with unmatched verifier should fail
        nfsd: randomize SETCLIENTID reply to help distinguish servers
        nfsd: set the MAY_NOTIFY_LOCK flag in OPEN replies
        nfs: add a new NFS4_OPEN_RESULT_MAY_NOTIFY_LOCK constant
        nfsd: add a LRU list for blocked locks
        nfsd: have nfsd4_lock use blocking locks for v4.1+ locks
        nfsd: plumb in a CB_NOTIFY_LOCK operation
        NFSD: fix corruption in notifier registration
        svcrdma: support Remote Invalidation
        svcrdma: Server-side support for rpcrdma_connect_private
        rpcrdma: RDMA/CM private message data structure
        svcrdma: Skip put_page() when send_reply() fails
        svcrdma: Tail iovec leaves an orphaned DMA mapping
        nfsd: fix dprintk in nfsd4_encode_getdeviceinfo
        nfsd: eliminate cb_minorversion field
        nfsd: don't set a FL_LAYOUT lease for flexfiles layouts
      27785564
    • Linus Torvalds's avatar
      Merge tag 'xfs-reflink-for-linus-4.9-rc1' of... · 35a891be
      Linus Torvalds authored
      Merge tag 'xfs-reflink-for-linus-4.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/dgc/linux-xfs
      
          < XFS has gained super CoW powers! >
           ----------------------------------
                  \   ^__^
                   \  (oo)\_______
                      (__)\       )\/\
                          ||----w |
                          ||     ||
      
      Pull XFS support for shared data extents from Dave Chinner:
       "This is the second part of the XFS updates for this merge cycle.  This
        pullreq contains the new shared data extents feature for XFS.
      
        Given the complexity and size of this change I am expecting - like the
        addition of reverse mapping last cycle - that there will be some
        follow-up bug fixes and cleanups around the -rc3 stage for issues that
        I'm sure will show up once the code hits a wider userbase.
      
        What it is:
      
        At the most basic level we are simply adding shared data extents to
        XFS - i.e. a single extent on disk can now have multiple owners. To do
        this we have to add new on-disk features to both track the shared
        extents and the number of times they've been shared. This is done by
        the new "refcount" btree that sits in every allocation group. When we
        share or unshare an extent, this tree gets updated.
      
        Along with this new tree, the reverse mapping tree needs to be updated
        to track each owner or a shared extent. This also needs to be updated
        ever share/unshare operation. These interactions at extent allocation
        and freeing time have complex ordering and recovery constraints, so
        there's a significant amount of new intent-based transaction code to
        ensure that operations are performed atomically from both the runtime
        and integrity/crash recovery perspectives.
      
        We also need to break sharing when writes hit a shared extent - this
        is where the new copy-on-write implementation comes in. We allocate
        new storage and copy the original data along with the overwrite data
        into the new location. We only do this for data as we don't share
        metadata at all - each inode has it's own metadata that tracks the
        shared data extents, the extents undergoing CoW and it's own private
        extents.
      
        Of course, being XFS, nothing is simple - we use delayed allocation
        for CoW similar to how we use it for normal writes. ENOSPC is a
        significant issue here - we build on the reservation code added in
        4.8-rc1 with the reverse mapping feature to ensure we don't get
        spurious ENOSPC issues part way through a CoW operation. These
        mechanisms also help minimise fragmentation due to repeated CoW
        operations. To further reduce fragmentation overhead, we've also
        introduced a CoW extent size hint, which indicates how large a region
        we should allocate when we execute a CoW operation.
      
        With all this functionality in place, we can hook up .copy_file_range,
        .clone_file_range and .dedupe_file_range and we gain all the
        capabilities of reflink and other vfs provided functionality that
        enable manipulation to shared extents. We also added a fallocate mode
        that explicitly unshares a range of a file, which we implemented as an
        explicit CoW of all the shared extents in a file.
      
        As such, it's a huge chunk of new functionality with new on-disk
        format features and internal infrastructure. It warns at mount time as
        an experimental feature and that it may eat data (as we do with all
        new on-disk features until they stabilise). We have not released
        userspace suport for it yet - userspace support currently requires
        download from Darrick's xfsprogs repo and build from source, so the
        access to this feature is really developer/tester only at this point.
        Initial userspace support will be released at the same time the kernel
        with this code in it is released.
      
        The new code causes 5-6 new failures with xfstests - these aren't
        serious functional failures but things the output of tests changing
        slightly due to perturbations in layouts, space usage, etc. OTOH,
        we've added 150+ new tests to xfstests that specifically exercise this
        new functionality so it's got far better test coverage than any
        functionality we've previously added to XFS.
      
        Darrick has done a pretty amazing job getting us to this stage, and
        special mention also needs to go to Christoph (review, testing,
        improvements and bug fixes) and Brian (caught several intricate bugs
        during review) for the effort they've also put in.
      
        Summary:
      
         - unshare range (FALLOC_FL_UNSHARE) support for fallocate
      
         - copy-on-write extent size hints (FS_XFLAG_COWEXTSIZE) for fsxattr
           interface
      
         - shared extent support for XFS
      
         - copy-on-write support for shared extents
      
         - copy_file_range support
      
         - clone_file_range support (implements reflink)
      
         - dedupe_file_range support
      
         - defrag support for reverse mapping enabled filesystems"
      
      * tag 'xfs-reflink-for-linus-4.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/dgc/linux-xfs: (71 commits)
        xfs: convert COW blocks to real blocks before unwritten extent conversion
        xfs: rework refcount cow recovery error handling
        xfs: clear reflink flag if setting realtime flag
        xfs: fix error initialization
        xfs: fix label inaccuracies
        xfs: remove isize check from unshare operation
        xfs: reduce stack usage of _reflink_clear_inode_flag
        xfs: check inode reflink flag before calling reflink functions
        xfs: implement swapext for rmap filesystems
        xfs: refactor swapext code
        xfs: various swapext cleanups
        xfs: recognize the reflink feature bit
        xfs: simulate per-AG reservations being critically low
        xfs: don't mix reflink and DAX mode for now
        xfs: check for invalid inode reflink flags
        xfs: set a default CoW extent size of 32 blocks
        xfs: convert unwritten status of reverse mappings for shared files
        xfs: use interval query for rmap alloc operations on shared files
        xfs: add shared rmap map/unmap/convert log item types
        xfs: increase log reservations for reflink
        ...
      35a891be
    • Linus Torvalds's avatar
      Merge tag 'pci-v4.9-changes-2' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci · 40bd3a5f
      Linus Torvalds authored
      PCI changes for the v4.9 merge window:
       "Here are some more changes I'd like to have in v4.9.  There's one
        small Tegra bug fix in the PHY poweroff path, which is only used in
        failure paths.
      
        The rest is all strictly cleanup that should make host bridge drivers
        more readable, but shouldn't actually change any behavior.
      
        Summary:
      
         - use local struct device pointers in many host bridge drivers for
           clarity
      
         - remove unused platform data
      
         - use generic DesignWare accessors
      
         - misc cleanups: remove redundant structure entries and re-order
           structure members to put comon generic fields first etc"
      
      * tag 'pci-v4.9-changes-2' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci: (108 commits)
        MAINTAINERS: Add maintainer for the PCIe Marvell Armada 8K driver
        MAINTAINERS: Add DT binding to the Aardvark PCIe driver maintainer
        PCI: rockchip: Indent "if" statement body
        PCI: hisi: Reorder struct hisi_pcie
        PCI: hisi: Pass device-specific struct to internal functions
        PCI: hisi: Include register block base in PCIE_SYS_STATE4 address
        PCI: dra7xx: Reorder struct dra7xx_pcie
        PCI: xilinx-nwl: Remove unused platform data
        PCI: xilinx-nwl: Add local struct device pointers
        PCI: xilinx: Removed unused xilinx_pcie_assign_msi() argument
        PCI: xilinx: Remove unused platform data
        PCI: xilinx: Add local struct device pointers
        PCI: xgene: Add register accessors
        PCI: xgene: Pass struct xgene_pcie_port to setup functions
        PCI: xgene: Remove unused platform data
        PCI: tegra: Remove unused platform data
        PCI: tegra: Add local struct device pointers
        PCI: tegra: Fix argument order in tegra_pcie_phy_disable()
        PCI: rockchip: Remove unused platform data
        PCI: rcar-gen2: Add local struct device pointers
        ...
      40bd3a5f
  2. 13 Oct, 2016 20 commits