summaryrefslogtreecommitdiffstats
path: root/drivers/s390
Commit message (Collapse)AuthorAgeFilesLines
* vfio/ccw: Use the new device life cycle helpersKevin Tian2022-09-212-7/+48
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | ccw is the only exception which cannot use vfio_alloc_device() because its private device structure is designed to serve both mdev and parent. Life cycle of the parent is managed by css_driver so vfio_ccw_private must be allocated/freed in css_driver probe/remove path instead of conforming to vfio core life cycle for mdev. Given that use a wait/completion scheme so the mdev remove path waits after vfio_put_device() until receiving a completion notification from @release. The completion indicates that all active references on vfio_device have been released. After that point although free of vfio_ccw_private is delayed to css_driver it's at least guaranteed to have no parallel reference on released vfio device part from other code paths. memset() in @probe is removed. vfio_device is either already cleared when probed for the first time or cleared in @release from last probe. The right fix is to introduce separate structures for mdev and parent, but this won't happen in short term per prior discussions. Remove vfio_init/uninit_group_dev() as no user now. Suggested-by: Jason Gunthorpe <jgg@nvidia.com> Signed-off-by: Kevin Tian <kevin.tian@intel.com> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Reviewed-by: Eric Farman <farman@linux.ibm.com> Link: https://lore.kernel.org/r/20220921104401.38898-14-kevin.tian@intel.com Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
* vfio/ap: Use the new device life cycle helpersYi Liu2022-09-211-21/+29
| | | | | | | | | | | and manage available_instances inside @init/@release. Signed-off-by: Yi Liu <yi.l.liu@intel.com> Signed-off-by: Kevin Tian <kevin.tian@intel.com> Reviewed-by: Tony Krowiak <akrowiak@linux.ibm.com> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Link: https://lore.kernel.org/r/20220921104401.38898-10-kevin.tian@intel.com Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
* Merge tag 's390-6.0-1' of ↵Linus Torvalds2022-08-202-0/+7
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux Pull s390 updates from Alexander Gordeev: - Fix a KVM crash on z12 and older machines caused by a wrong assumption that Query AP Configuration Information is always available. - Lower severity of excessive Hypervisor filesystem error messages when booting under KVM. * tag 's390-6.0-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: s390/ap: fix crash on older machines based on QCI info missing s390/hypfs: avoid error message under KVM
| * s390/ap: fix crash on older machines based on QCI info missingHarald Freudenberger2022-08-152-0/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | On older z series machines (z12 and older) there is no QCI info available. The AP code took care of this and the AP bus scan then switched to simple probing via TAPQ. With commit 283915850a44 ("s390/ap: notify drivers on config changed and scan complete callbacks") some code was introduced which silently assumed that the QCI info is always available. However, with KVM simulating an older machine (z12) the result was a kernel crash. Funnily the same crash does not happen on LPAR - maybe because NULL is a valid pointer and reading some data from address 0 also works fine. This fix now improves the code to be aware that the QCI instruction may not be available on older machines and thus the two pointers to QCI info structs may simple be NULL. However, on a machine not providing the QCI info the two callbacks to the zcrypt device drivers on_config_changed() and on_scan_complete() provide parameters which are pointers to a QCI info struct. These both callbacks are NOT served if there is no QCI info available. The only consumer of these callbacks is the vfio device driver. This driver only supports CEX4 and higher. All physical machines which are able to provide CEX4 cards have QCI support available. So there is no sense in for example fill the QCI info struct by hand with looping over cards and queues and TAPQ each APQN. Signed-off-by: Harald Freudenberger <freude@linux.ibm.com> Signed-off-by: Tony Krowiak <akrowiak@linux.ibm.com> Cc: stable@vger.kernel.org Fixes: 283915850a44 ("s390/ap: notify drivers on config changed and scan complete callbacks") Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
* | virtio: Revert "virtio: find_vqs() add arg sizes"Michael S. Tsirkin2022-08-161-1/+0
|/ | | | | | | | | | | | | | | | | This reverts commit a10fba0377145fccefea4dc4dd5915b7ed87e546: the proposed API isn't supported on all transports but no effort was made to address this. It might not be hard to fix if we want to: maybe just rename size to size_hint and make sure legacy transports ignore the hint. But it's not sure what the benefit is in any case, so let's drop it. Fixes: a10fba037714 ("virtio: find_vqs() add arg sizes") Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Message-Id: <20220816053602.173815-8-mst@redhat.com>
* Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsiLinus Torvalds2022-08-133-13/+26
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull more SCSI updates from James Bottomley: "Mostly small bug fixes and trivial updates. The major new core update is a change to the way device, target and host reference counting is done to try to make it more robust (this change has soaked for a while to try to winkle out any bugs)" * tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: scsi: pm8001: Fix typo 'the the' in comment scsi: megaraid_sas: Remove redundant variable cmd_type scsi: FlashPoint: Remove redundant variable bm_int_st scsi: zfcp: Fix missing auto port scan and thus missing target ports scsi: core: Call blk_mq_free_tag_set() earlier scsi: core: Simplify LLD module reference counting scsi: core: Make sure that hosts outlive targets scsi: core: Make sure that targets outlive devices scsi: ufs: ufs-pci: Correct check for RESET DSM scsi: target: core: De-RCU of se_lun and se_lun acl scsi: target: core: Fix race during ACL removal scsi: ufs: core: Correct ufshcd_shutdown() flow scsi: ufs: core: Increase the maximum data buffer size scsi: lpfc: Check the return value of alloc_workqueue()
| * scsi: zfcp: Fix missing auto port scan and thus missing target portsSteffen Maier2022-08-013-13/+26
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Case (1): The only waiter on wka_port->completion_wq is zfcp_fc_wka_port_get() trying to open a WKA port. As such it should only be woken up by WKA port *open* responses, not by WKA port close responses. Case (2): A close WKA port response coming in just after having sent a new open WKA port request and before blocking for the open response with wait_event() in zfcp_fc_wka_port_get() erroneously renders the wait_event a NOP because the close handler overwrites wka_port->status. Hence the wait_event condition is erroneously true and it does not enter blocking state. With non-negligible probability, the following time space sequence happens depending on timing without this fix: user process ERP thread zfcp work queue tasklet system work queue ============ ========== =============== ======= ================= $ echo 1 > online zfcp_ccw_set_online zfcp_ccw_activate zfcp_erp_adapter_reopen msleep scan backoff zfcp_erp_strategy | ... | zfcp_erp_action_cleanup | ... | queue delayed scan_work | queue ns_up_work | ns_up_work: | zfcp_fc_wka_port_get | open wka request | open response | GSPN FC-GS | RSPN FC-GS [NPIV-only] | zfcp_fc_wka_port_put | (--wka->refcount==0) | sched delayed wka->work | ~~~Case (1)~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ zfcp_erp_wait flush scan_work | wka->work: | wka->status=CLOSING | close wka request | scan_work: | zfcp_fc_wka_port_get | (wka->status==CLOSING) | wka->status=OPENING | open wka request | wait_event | | close response | | wka->status=OFFLINE | | wake_up /*WRONG*/ ~~~Case (2)~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ | wka->work: | wka->status=CLOSING | close wka request zfcp_erp_wait flush scan_work | scan_work: | zfcp_fc_wka_port_get | (wka->status==CLOSING) | wka->status=OPENING | open wka request | close response | wka->status=OFFLINE | wake_up /*WRONG&NOP*/ | wait_event /*NOP*/ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ | (wka->status!=ONLINE) | return -EIO | return early open response wka->status=ONLINE wake_up /*NOP*/ So we erroneously end up with no automatic port scan. This is a big problem when it happens during boot. The timing is influenced by v3.19 commit 18f87a67e6d6 ("zfcp: auto port scan resiliency"). Fix it by fully mutually excluding zfcp_fc_wka_port_get() and zfcp_fc_wka_port_offline(). For that to work, we make the latter block until we got the response for a close WKA port. In order not to penalize the system workqueue, we move wka_port->work to our own adapter workqueue. Note that before v2.6.30 commit 828bc1212a68 ("[SCSI] zfcp: Set WKA-port to offline on adapter deactivation"), zfcp did block in zfcp_fc_wka_port_offline() as well, but with a different condition. While at it, make non-functional cleanups to improve code reading in zfcp_fc_wka_port_get(). If we cannot send the WKA port open request, don't rely on the subsequent wait_event condition to immediately let this case pass without blocking. Also don't want to rely on the additional condition handling the refcount to be skipped just to finally return with -EIO. Link: https://lore.kernel.org/r/20220729162529.1620730-1-maier@linux.ibm.com Fixes: 5ab944f97e09 ("[SCSI] zfcp: attach and release SAN nameserver port on demand") Cc: <stable@vger.kernel.org> #v2.6.28+ Reviewed-by: Benjamin Block <bblock@linux.ibm.com> Signed-off-by: Steffen Maier <maier@linux.ibm.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
* | Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhostLinus Torvalds2022-08-121-0/+4
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull virtio updates from Michael Tsirkin: - A huge patchset supporting vq resize using the new vq reset capability - Features, fixes, and cleanups all over the place * tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost: (88 commits) vdpa/mlx5: Fix possible uninitialized return value vdpa_sim_blk: add support for discard and write-zeroes vdpa_sim_blk: add support for VIRTIO_BLK_T_FLUSH vdpa_sim_blk: make vdpasim_blk_check_range usable by other requests vdpa_sim_blk: check if sector is 0 for commands other than read or write vdpa_sim: Implement suspend vdpa op vhost-vdpa: uAPI to suspend the device vhost-vdpa: introduce SUSPEND backend feature bit vdpa: Add suspend operation virtio-blk: Avoid use-after-free on suspend/resume virtio_vdpa: support the arg sizes of find_vqs() vhost-vdpa: Call ida_simple_remove() when failed vDPA: fix 'cast to restricted le16' warnings in vdpa.c vDPA: !FEATURES_OK should not block querying device config space vDPA/ifcvf: support userspace to query features and MQ of a management device vDPA/ifcvf: get_config_size should return a value no greater than dev implementation vhost scsi: Allow user to control num virtqueues vhost-scsi: Fix max number of virtqueues vdpa/mlx5: Support different address spaces for control and data vdpa/mlx5: Implement susupend virtqueue callback ...
| * | virtio: find_vqs() add arg sizesXuan Zhuo2022-08-111-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | find_vqs() adds a new parameter sizes to specify the size of each vq vring. NULL as sizes means that all queues in find_vqs() use the maximum size. A value in the array is 0, which means that the corresponding queue uses the maximum size. In the split scenario, the meaning of size is the largest size, because it may be limited by memory, the virtio core will try a smaller size. And the size is power of 2. Signed-off-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com> Acked-by: Hans de Goede <hdegoede@redhat.com> Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org> Acked-by: Jason Wang <jasowang@redhat.com> Message-Id: <20220801063902.129329-34-xuanzhuo@linux.alibaba.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
| * | virtio: record the maximum queue num supported by the device.Xuan Zhuo2022-08-111-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | virtio-net can display the maximum (supported by hardware) ring size in ethtool -g eth0. When the subsequent patch implements vring reset, it can judge whether the ring size passed by the driver is legal based on this. Signed-off-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com> Acked-by: Jason Wang <jasowang@redhat.com> Message-Id: <20220801063902.129329-2-xuanzhuo@linux.alibaba.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
* | | Merge tag 'net-6.0-rc1' of ↵Linus Torvalds2022-08-112-132/+48
|\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net Pull networking fixes from Jakub Kicinski: "Including fixes from bluetooth, bpf, can and netfilter. A little larger than usual but it's all fixes, no late features. It's large partially because of timing, and partially because of follow ups to stuff that got merged a week or so before the merge window and wasn't as widely tested. Maybe the Bluetooth fixes are a little alarming so we'll address that, but the rest seems okay and not scary. Notably we're including a fix for the netfilter Kconfig [1], your WiFi warning [2] and a bluetooth fix which should unblock syzbot [3]. Current release - regressions: - Bluetooth: - don't try to cancel uninitialized works [3] - L2CAP: fix use-after-free caused by l2cap_chan_put - tls: rx: fix device offload after recent rework - devlink: fix UAF on failed reload and leftover locks in mlxsw Current release - new code bugs: - netfilter: - flowtable: fix incorrect Kconfig dependencies [1] - nf_tables: fix crash when nf_trace is enabled - bpf: - use proper target btf when exporting attach_btf_obj_id - arm64: fixes for bpf trampoline support - Bluetooth: - ISO: unlock on error path in iso_sock_setsockopt() - ISO: fix info leak in iso_sock_getsockopt() - ISO: fix iso_sock_getsockopt for BT_DEFER_SETUP - ISO: fix memory corruption on iso_pinfo.base - ISO: fix not using the correct QoS - hci_conn: fix updating ISO QoS PHY - phy: dp83867: fix get nvmem cell fail Previous releases - regressions: - wifi: cfg80211: fix validating BSS pointers in __cfg80211_connect_result [2] - atm: bring back zatm uAPI after ATM had been removed - properly fix old bug making bonding ARP monitor mode not being able to work with software devices with lockless Tx - tap: fix null-deref on skb->dev in dev_parse_header_protocol - revert "net: usb: ax88179_178a needs FLAG_SEND_ZLP" it helps some devices and breaks others - netfilter: - nf_tables: many fixes rejecting cross-object linking which may lead to UAFs - nf_tables: fix null deref due to zeroed list head - nf_tables: validate variable length element extension - bgmac: fix a BUG triggered by wrong bytes_compl - bcmgenet: indicate MAC is in charge of PHY PM Previous releases - always broken: - bpf: - fix bad pointer deref in bpf_sys_bpf() injected via test infra - disallow non-builtin bpf programs calling the prog_run command - don't reinit map value in prealloc_lru_pop - fix UAFs during the read of map iterator fd - fix invalidity check for values in sk local storage map - reject sleepable program for non-resched map iterator - mptcp: - move subflow cleanup in mptcp_destroy_common() - do not queue data on closed subflows - virtio_net: fix memory leak inside XDP_TX with mergeable - vsock: fix memory leak when multiple threads try to connect() - rework sk_user_data sharing to prevent psock leaks - geneve: fix TOS inheriting for ipv4 - tunnels & drivers: do not use RT_TOS for IPv6 flowlabel - phy: c45 baset1: do not skip aneg configuration if clock role is not specified - rose: avoid overflow when /proc displays timer information - x25: fix call timeouts in blocking connects - can: mcp251x: fix race condition on receive interrupt - can: j1939: - replace user-reachable WARN_ON_ONCE() with netdev_warn_once() - fix memory leak of skbs in j1939_session_destroy() Misc: - docs: bpf: clarify that many things are not uAPI - seg6: initialize induction variable to first valid array index (to silence clang vs objtool warning) - can: ems_usb: fix clang 14's -Wunaligned-access warning" * tag 'net-6.0-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (117 commits) net: atm: bring back zatm uAPI dpaa2-eth: trace the allocated address instead of page struct net: add missing kdoc for struct genl_multicast_group::flags nfp: fix use-after-free in area_cache_get() MAINTAINERS: use my korg address for mt7601u mlxsw: minimal: Fix deadlock in ports creation bonding: fix reference count leak in balance-alb mode net: usb: qmi_wwan: Add support for Cinterion MV32 bpf: Shut up kern_sys_bpf warning. net/tls: Use RCU API to access tls_ctx->netdev tls: rx: device: don't try to copy too much on detach tls: rx: device: bound the frag walk net_sched: cls_route: remove from list when handle is 0 selftests: forwarding: Fix failing tests with old libnet net: refactor bpf_sk_reuseport_detach() net: fix refcount bug in sk_psock_get (2) selftests/bpf: Ensure sleepable program is rejected by hash map iter selftests/bpf: Add write tests for sk local storage map iterator selftests/bpf: Add tests for reading a dangling map iter fd bpf: Only allow sleepable program for resched-able iterator ...
| * | | s390/qeth: cache link_info for ethtoolAlexandra Winter2022-08-082-132/+48
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Since commit e6e771b3d897 ("s390/qeth: detach netdevice while card is offline") there was a timing window during recovery, that qeth_query_card_info could be sent to the card, even before it was ready for it, leading to a failing card recovery. There is evidence that this window was hit, as not all callers of get_link_ksettings() check for netif_device_present. Use cached values in qeth_get_link_ksettings(), instead of calling qeth_query_card_info() and falling back to default values in case it fails. Link info is already updated when the card goes online, e.g. after STARTLAN (physical link up). Set the link info to default values, when the card goes offline or at STOPLAN (physical link down). A follow-on patch will improve values reported for link down. Fixes: e6e771b3d897 ("s390/qeth: detach netdevice while card is offline") Signed-off-by: Alexandra Winter <wintera@linux.ibm.com> Reviewed-by: Thorsten Winkler <twinkler@linux.ibm.com> Link: https://lore.kernel.org/r/20220805155714.59609-1-wintera@linux.ibm.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
* | | | Merge tag 's390-5.20-1' of ↵Linus Torvalds2022-08-069-479/+1230
|\ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux Pull s390 updates from Alexander Gordeev: - Rework copy_oldmem_page() callback to take an iov_iter. This includes a few prerequisite updates and fixes to the oldmem reading code. - Rework cpufeature implementation to allow for various CPU feature indications, which is not only limited to hardware capabilities, but also allows CPU facilities. - Use the cpufeature rework to autoload Ultravisor module when CPU facility 158 is available. - Add ELF note type for encrypted CPU state of a protected virtual CPU. The zgetdump tool from s390-tools package will decrypt the CPU state using a Customer Communication Key and overwrite respective notes to make the data accessible for crash and other debugging tools. - Use vzalloc() instead of vmalloc() + memset() in ChaCha20 crypto test. - Fix incorrect recovery of kretprobe modified return address in stacktrace. - Switch the NMI handler to use generic irqentry_nmi_enter() and irqentry_nmi_exit() helper functions. - Rework the cryptographic Adjunct Processors (AP) pass-through design to support dynamic changes to the AP matrix of a running guest as well as to implement more of the AP architecture. - Minor boot code cleanups. - Grammar and typo fixes to hmcdrv and tape drivers. * tag 's390-5.20-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (46 commits) Revert "s390/smp: enforce lowcore protection on CPU restart" Revert "s390/smp: rework absolute lowcore access" Revert "s390/smp,ptdump: add absolute lowcore markers" s390/unwind: fix fgraph return address recovery s390/nmi: use irqentry_nmi_enter()/irqentry_nmi_exit() s390: add ELF note type for encrypted CPU state of a PV VCPU s390/smp,ptdump: add absolute lowcore markers s390/smp: rework absolute lowcore access s390/setup: rearrange absolute lowcore initialization s390/boot: cleanup adjust_to_uv_max() function s390/smp: enforce lowcore protection on CPU restart s390/tape: fix comment typo s390/hmcdrv: fix Kconfig "its" grammar s390/docs: fix warnings for vfio_ap driver doc s390/docs: fix warnings for vfio_ap driver lock usage doc s390/crash: support multi-segment iterators s390/crash: use static swap buffer for copy_to_user_real() s390/crash: move copy_to_user_real() to crash_dump.c s390/zcore: fix race when reading from hardware system area s390/crash: fix incorrect number of bytes to copy to user space ...
| * | | | s390/tape: fix comment typoJason Wang2022-07-281-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Remove duplicated `that' in a comment Signed-off-by: Jason Wang <wangborong@cdjrlc.com> Link: https://lore.kernel.org/r/20220715053838.5005-1-wangborong@cdjrlc.com [agordeev@linux.ibm.com rephrased commit message] Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
| * | | | s390/hmcdrv: fix Kconfig "its" grammarRandy Dunlap2022-07-281-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Use the possessive "its" instead of the contraction "it's" where appropriate. Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Alexander Gordeev <agordeev@linux.ibm.com> Cc: linux-s390@vger.kernel.org Link: https://lore.kernel.org/r/20220715020010.12678-1-rdunlap@infradead.org Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
| * | | | Merge branch 'vmcore-iov_iter' into featuresAlexander Gordeev2022-07-281-29/+26
| |\ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull changes that finalize switching of copy_oldmem_page() callback to iov_iter interface. These changes were pulled in work.iov_iter of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs.git Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
| | * | | | s390/crash: support multi-segment iteratorsAlexander Gordeev2022-07-201-35/+23
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Make it possible to handle not only single-, but also multi- segment iterators in copy_oldmem_iter() callback. Change the semantics of called functions to match the iterator model - instead of an error code the exact number of bytes copied is returned. The swap page used to copy data to user space is adopted for kernel space too. That does not bring any performance impact. Suggested-by: Matthew Wilcox <willy@infradead.org> Fixes: cc02e6e21aa5 ("s390/crash: add missing iterator advance in copy_oldmem_page()") Acked-by: Heiko Carstens <hca@linux.ibm.com> Tested-by: Alexander Egorenkov <egorenar@linux.ibm.com> Link: https://lore.kernel.org/r/5af6da3a0bffe48a90b0b7139ecf6a818b2d18e8.1658206891.git.agordeev@linux.ibm.com Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
| | * | | | s390/zcore: fix race when reading from hardware system areaAlexander Gordeev2022-07-201-1/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Memory buffer used for reading out data from hardware system area is not protected against concurrent access. Reported-by: Matthew Wilcox <willy@infradead.org> Fixes: 411ed3225733 ("[S390] zfcpdump support.") Acked-by: Heiko Carstens <hca@linux.ibm.com> Tested-by: Alexander Egorenkov <egorenar@linux.ibm.com> Link: https://lore.kernel.org/r/e68137f0f9a0d2558f37becc20af18e2939934f6.1658206891.git.agordeev@linux.ibm.com Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
| * | | | | s390/uvdevice: autoload module based on CPU facilitySteffen Eiden2022-07-191-3/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Make sure the uvdevice driver will be automatically loaded when facility 158 is available. Signed-off-by: Steffen Eiden <seiden@linux.ibm.com> Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com> Link: https://lore.kernel.org/r/20220713125644.16121-4-seiden@linux.ibm.com Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
| * | | | | s390/cpufeature: rework to allow more than only hwcap bitsHeiko Carstens2022-07-191-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Rework cpufeature implementation to allow for various cpu feature indications, which is not only limited to hwcap bits. This is achieved by adding a sequential list of cpu feature numbers, where each of them is mapped to an entry which indicates what this number is about. Each entry contains a type member, which indicates what feature name space to look into (e.g. hwcap, or cpu facility). If wanted this allows also to automatically load modules only in e.g. z/VM configurations. Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Steffen Eiden <seiden@linux.ibm.com> Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com> Reviewed-by: Hendrik Brueckner <brueckner@linux.ibm.com> Link: https://lore.kernel.org/r/20220713125644.16121-2-seiden@linux.ibm.com Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
| * | | | | s390/vfio-ap: handle config changed and scan complete notificationTony Krowiak2022-07-193-5/+350
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch implements two new AP driver callbacks: void (*on_config_changed)(struct ap_config_info *new_config_info, struct ap_config_info *old_config_info); void (*on_scan_complete)(struct ap_config_info *new_config_info, struct ap_config_info *old_config_info); The on_config_changed callback is invoked at the start of the AP bus scan function when it determines that the host AP configuration information has changed since the previous scan. The vfio_ap device driver registers a callback function for this callback that performs the following operations: 1. Unplugs the adapters, domains and control domains removed from the host's AP configuration from the guests to which they are assigned in a single operation. 2. Stores bitmaps identifying the adapters, domains and control domains added to the host's AP configuration with the structure representing the mediated device. When the vfio_ap device driver's probe callback is subsequently invoked, the probe function will recognize that the queue is being probed due to a change in the host's AP configuration and the plugging of the queue into the guest will be bypassed. The on_scan_complete callback is invoked after the ap bus scan is completed if the host AP configuration data has changed. The vfio_ap device driver registers a callback function for this callback that hot plugs each queue and control domain added to the AP configuration for each guest using them in a single hot plug operation. Signed-off-by: Tony Krowiak <akrowiak@linux.ibm.com> Reviewed-by: Jason J. Herne <jjherne@linux.ibm.com> Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
| * | | | | s390/vfio-ap: sysfs attribute to display the guest's matrixTony Krowiak2022-07-191-13/+35
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The matrix of adapters and domains configured in a guest's APCB may differ from the matrix of adapters and domains assigned to the matrix mdev, so this patch introduces a sysfs attribute to display the matrix of adapters and domains that are or will be assigned to the APCB of a guest that is or will be using the matrix mdev. For a matrix mdev denoted by $uuid, the guest matrix can be displayed as follows: cat /sys/devices/vfio_ap/matrix/$uuid/guest_matrix Signed-off-by: Tony Krowiak <akrowiak@linux.ibm.com> Reviewed-by: Jason J. Herne <jjherne@linux.ibm.com> Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
| * | | | | s390/vfio-ap: implement in-use callback for vfio_ap driverTony Krowiak2022-07-194-8/+80
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Let's implement the callback to indicate when an APQN is in use by the vfio_ap device driver. The callback is invoked whenever a change to the apmask or aqmask would result in one or more queue devices being removed from the driver. The vfio_ap device driver will indicate a resource is in use if the APQN of any of the queue devices to be removed are assigned to any of the matrix mdevs under the driver's control. There is potential for a deadlock condition between the matrix_dev->guests_lock used to lock the guest during assignment of adapters and domains and the ap_perms_mutex locked by the AP bus when changes are made to the sysfs apmask/aqmask attributes. The AP Perms lock controls access to the objects that store the adapter numbers (ap_perms) and domain numbers (aq_perms) for the sysfs /sys/bus/ap/apmask and /sys/bus/ap/aqmask attributes. These attributes identify which queues are reserved for the zcrypt default device drivers. Before allowing a bit to be removed from either mask, the AP bus must check with the vfio_ap device driver to verify that none of the queues are assigned to any of its mediated devices. The apmask/aqmask attributes can be written or read at any time from userspace, so care must be taken to prevent a deadlock with asynchronous operations that might be taking place in the vfio_ap device driver. For example, consider the following: 1. A system administrator assigns an adapter to a mediated device under the control of the vfio_ap device driver. The driver will need to first take the matrix_dev->guests_lock to potentially hot plug the adapter into the KVM guest. 2. At the same time, a system administrator sets a bit in the sysfs /sys/bus/ap/ap_mask attribute. To complete the operation, the AP bus must: a. Take the ap_perms_mutex lock to update the object storing the values for the /sys/bus/ap/ap_mask attribute. b. Call the vfio_ap device driver's in-use callback to verify that the queues now being reserved for the default zcrypt drivers are not assigned to a mediated device owned by the vfio_ap device driver. To do the verification, the in-use callback function takes the matrix_dev->guests_lock, but has to wait because it is already held by the operation in 1 above. 3. The vfio_ap device driver calls an AP bus function to verify that the new queues resulting from the assignment of the adapter in step 1 are not reserved for the default zcrypt device driver. This AP bus function tries to take the ap_perms_mutex lock but gets stuck waiting for the waiting for the lock due to step 2a above. Consequently, we have the following deadlock situation: matrix_dev->guests_lock locked (1) ap_perms_mutex lock locked (2a) Waiting for matrix_dev->gusts_lock (2b) which is currently held (1) Waiting for ap_perms_mutex lock (3) which is currently held (2a) To prevent this deadlock scenario, the function called in step 3 will no longer take the ap_perms_mutex lock and require the caller to take the lock. The lock will be the first taken by the adapter/domain assignment functions in the vfio_ap device driver to maintain the proper locking order. Signed-off-by: Tony Krowiak <akrowiak@linux.ibm.com> Reviewed-by: Jason J. Herne <jjherne@linux.ibm.com> Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
| * | | | | s390/vfio-ap: reset queues after adapter/domain unassignmentTony Krowiak2022-07-192-40/+114
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When an adapter or domain is unassigned from an mdev attached to a KVM guest, one or more of the guest's queues may get dynamically removed. Since the removed queues could get re-assigned to another mdev, they need to be reset. So, when an adapter or domain is unassigned from the mdev, the queues that are removed from the guest's AP configuration (APCB) will be reset. Signed-off-by: Tony Krowiak <akrowiak@linux.ibm.com> Reviewed-by: Jason J. Herne <jjherne@linux.ibm.com> Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
| * | | | | s390/vfio-ap: hot plug/unplug of AP devices when probed/removedTony Krowiak2022-07-191-6/+17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When an AP queue device is probed or removed, if the mediated device is attached to a KVM guest, the mediated device's adapter, domain and control domain bitmaps must be filtered to update the guest's APCB and if any changes are detected, the guest's APCB must then be hot plugged into the guest to reflect those changes to the guest. Signed-off-by: Tony Krowiak <akrowiak@linux.ibm.com> Reviewed-by: Jason J. Herne <jjherne@linux.ibm.com> Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
| * | | | | s390/vfio-ap: allow hot plug/unplug of AP devices when assigned/unassignedTony Krowiak2022-07-191-55/+57
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Let's hot plug an adapter, domain or control domain into the guest when it is assigned to a matrix mdev that is attached to a KVM guest. Likewise, let's hot unplug an adapter, domain or control domain from the guest when it is unassigned from a matrix_mdev that is attached to a KVM guest. Whenever an assignment or unassignment of an adapter, domain or control domain is performed, the APQNs and control domains assigned to the matrix mdev will be filtered and assigned to the AP control block (APCB) that supplies the AP configuration to the guest so that no adapter, domain or control domain that is not in the host's AP configuration nor any APQN that does not reference a queue device bound to the vfio_ap device driver is assigned. After updating the APCB, if the mdev is in use by a KVM guest, it is hot plugged into the guest to dynamically provide access to the adapters, domains and control domains provided via the newly refreshed APCB. Signed-off-by: Tony Krowiak <akrowiak@linux.ibm.com> Reviewed-by: Jason J. Herne <jjherne@linux.ibm.com> Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
| * | | | | s390/vfio-ap: prepare for dynamic update of guest's APCB on queue probe/removeTony Krowiak2022-07-191-39/+85
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The callback functions for probing and removing a queue device must take and release the locks required to perform a dynamic update of a guest's APCB in the proper order. The proper order for taking the locks is: matrix_dev->guests_lock => kvm->lock => matrix_dev->mdevs_lock The proper order for releasing the locks is: matrix_dev->mdevs_lock => kvm->lock => matrix_dev->guests_lock A new helper function is introduced to be used by the probe callback to acquire the required locks. Since the probe callback only has access to a queue device when it is called, the helper function will find the ap_matrix_mdev object to which the queue device's APQN is assigned and return it so the KVM guest to which the mdev is attached can be dynamically updated. Note that in order to find the ap_matrix_mdev (matrix_mdev) object, it is necessary to search the matrix_dev->mdev_list. This presents a locking order dilemma because the matrix_dev->mdevs_lock can't be taken to protect against changes to the list while searching for the matrix_mdev to which a queue device's APQN is assigned. This is due to the fact that the proper locking order requires that the matrix_dev->mdevs_lock be taken after both the matrix_mdev->kvm->lock and the matrix_dev->mdevs_lock. Consequently, the matrix_dev->guests_lock will be used to protect against removal of a matrix_mdev object from the list while a queue device is being probed. This necessitates changes to the mdev probe/remove callback functions to take the matrix_dev->guests_lock prior to removing a matrix_mdev object from the list. A new macro is also introduced to acquire the locks required to dynamically update the guest's APCB in the proper order when a queue device is removed. Signed-off-by: Tony Krowiak <akrowiak@linux.ibm.com> Reviewed-by: Jason J. Herne <jjherne@linux.ibm.com> Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
| * | | | | s390/vfio-ap: prepare for dynamic update of guest's APCB on assign/unassignTony Krowiak2022-07-191-12/+59
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The functions backing the matrix mdev's sysfs attribute interfaces to assign/unassign adapters, domains and control domains must take and release the locks required to perform a dynamic update of a guest's APCB in the proper order. The proper order for taking the locks is: matrix_dev->guests_lock => kvm->lock => matrix_dev->mdevs_lock The proper order for releasing the locks is: matrix_dev->mdevs_lock => kvm->lock => matrix_dev->guests_lock Two new macros are introduced for this purpose: One to take the locks and the other to release the locks. These macros will be used by the assignment/unassignment functions to prepare for dynamic update of the KVM guest's APCB. Signed-off-by: Tony Krowiak <akrowiak@linux.ibm.com> Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
| * | | | | s390/vfio-ap: use proper locking order when setting/clearing KVM pointerTony Krowiak2022-07-191-10/+48
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The group notifier that handles the VFIO_GROUP_NOTIFY_SET_KVM event must use the required locks in proper locking order to dynamically update the guest's APCB. The proper locking order is: 1. matrix_dev->guests_lock: required to use the KVM pointer to update a KVM guest's APCB. 2. matrix_mdev->kvm->lock: required to update a KVM guest's APCB. 3. matrix_dev->mdevs_lock: required to store or access the data stored in a struct ap_matrix_mdev instance. Two macros are introduced to acquire and release the locks in the proper order. These macros are now used by the group notifier functions. Signed-off-by: Tony Krowiak <akrowiak@linux.ibm.com> Reviewed-by: Jason J. Herne <jjherne@linux.ibm.com> Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
| * | | | | s390/vfio-ap: introduce new mutex to control access to the KVM pointerTony Krowiak2022-07-192-0/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The vfio_ap device driver registers for notification when the pointer to the KVM object for a guest is set. Recall that the KVM lock (kvm->lock) mutex must be taken outside of the matrix_dev->lock mutex to prevent the reporting by lockdep of a circular locking dependency (a.k.a., a lockdep splat): * see commit 0cc00c8d4050 ("Fix circular lockdep when setting/clearing crypto masks") * see commit 86956e70761b ("replace open coded locks for VFIO_GROUP_NOTIFY_SET_KVM notification") With the introduction of support for hot plugging/unplugging AP devices passed through to a KVM guest, a new guests_lock mutex is introduced to ensure the proper locking order is maintained: struct ap_matrix_dev { ... struct mutex guests_lock; ... } The matrix_dev->guests_lock controls access to the matrix_mdev instances that hold the state for AP devices that have been passed through to a KVM guest. This lock must be held to control access to the KVM pointer (matrix_mdev->kvm) while the vfio_ap device driver is using it to plug/unplug AP devices passed through to the KVM guest. Keep in mind, the proper locking order must be maintained whenever dynamically updating a KVM guest's APCB to plug/unplug adapters, domains and control domains: 1. matrix_dev->guests_lock: required to use the KVM pointer - stored in a struct ap_matrix_mdev instance - to update a KVM guest's APCB 2. matrix_mdev->kvm->lock: required to update a guest's APCB 3. matrix_dev->mdevs_lock: required to access data stored in a struct ap_matrix_mdev instance. Signed-off-by: Tony Krowiak <akrowiak@linux.ibm.com> Reviewed-by: Jason J. Herne <jjherne@linux.ibm.com> Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
| * | | | | s390/vfio-ap: rename matrix_dev->lock mutex to matrix_dev->mdevs_lockTony Krowiak2022-07-193-40/+42
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The matrix_dev->lock mutex is being renamed to matrix_dev->mdevs_lock to better reflect its purpose, which is to control access to the state of the mediated devices under the control of the vfio_ap device driver. Signed-off-by: Tony Krowiak <akrowiak@linux.ibm.com> Reviewed-by: Jason J. Herne <jjherne@linux.ibm.com> Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
| * | | | | s390/vfio-ap: allow assignment of unavailable AP queues to mdev deviceTony Krowiak2022-07-191-171/+53
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The current implementation does not allow assignment of an AP adapter or domain to an mdev device if each APQN resulting from the assignment does not reference an AP queue device that is bound to the vfio_ap device driver. This patch allows assignment of AP resources to the matrix mdev as long as the APQNs resulting from the assignment: 1. Are not reserved by the AP BUS for use by the zcrypt device drivers. 2. Are not assigned to another matrix mdev. The rationale behind this is that the AP architecture does not preclude assignment of APQNs to an AP configuration profile that are not available to the system. Signed-off-by: Tony Krowiak <akrowiak@linux.ibm.com> Reviewed-by: Halil Pasic <pasic@linux.ibm.com> Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
| * | | | | s390/vfio-ap: refresh guest's APCB by filtering AP resources assigned to mdevTony Krowiak2022-07-191-3/+98
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Refresh the guest's APCB by filtering the APQNs and control domain numbers assigned to the matrix mdev. Filtering of APQNs: ----------------- APQNs that do not reference an AP queue device bound to the vfio_ap device driver must be filtered from the APQNs assigned to the matrix mdev before they can be assigned to the guest's APCB. Given that the APQNs are configured in the guest's APCB as a matrix of APIDs (adapters) and APQIs (domains), it is not possible to filter an individual APQN. For example, suppose the matrix of APQNs is structured as follows: APIDs 3 4 5 0 (3,0) (4,0) (5,0) APQIs 1 (3,1) (4,1) (5,1) 2 (3,2) (4,2) (5,2) Now suppose APQN (4,1) does not reference a queue device bound to the vfio_ap device driver. If we filter APID 4, the APQNs (4,0), (4,1) and (4,2) will be removed. Similarly, if we filter domain 1, APQNs (3,1), (4,1) and (5,1) will be removed. To resolve this dilemma, the choice was made to filter the APID - in this case 4 - from the guest's APCB. The reason for this design decision is because the APID references an AP adapter which is a real hardware device that can be physically installed, removed, enabled or disabled; whereas, a domain is a partition within the adapter. It therefore better reflects reality to remove the APID from the guest's APCB. Filtering of control domains: ---------------------------- Any control domains that are not assigned to the host's AP configuration will be filtered from those assigned to the matrix mdev before assigning them to the guest's APCB. Signed-off-by: Tony Krowiak <akrowiak@linux.ibm.com> Reviewed-by: Jason J. Herne <jjherne@linux.ibm.com> Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
| * | | | | s390/vfio-ap: introduce shadow APCBTony Krowiak2022-07-192-4/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The APCB is a field within the CRYCB that provides the AP configuration to a KVM guest. Let's introduce a shadow copy of the KVM guest's APCB and maintain it for the lifespan of the guest. The shadow APCB serves the following purposes: 1. The shadow APCB can be maintained even when the mediated device is not currently in use by a KVM guest. Since the mediated device's AP configuration is filtered to ensure that no AP queues are passed through to the KVM guest that are not bound to the vfio_ap device driver or available to the host, the mediated device's AP configuration may differ from the guest's. Having a shadow of a guest's APCB allows us to provide a sysfs interface to view the guest's APCB even if the mediated device is not currently passed through to a KVM guest. This can aid in problem determination when the guest is unexpectedly missing AP resources. 2. If filtering was done in-place for the real APCB, the guest could pick up a transient state. Doing the filtering on a shadow and transferring the AP configuration to the real APCB after the guest is started or when AP resources are assigned to or unassigned from the mediated device, or when the host configuration changes, the guest's AP configuration will never be in a transient state. Signed-off-by: Tony Krowiak <akrowiak@linux.ibm.com> Reviewed-by: Halil Pasic <pasic@linux.ibm.com> Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
| * | | | | s390/vfio-ap: manage link between queue struct and matrix mdevTony Krowiak2022-07-192-37/+168
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Let's create links between each queue device bound to the vfio_ap device driver and the matrix mdev to which the queue's APQN is assigned. The idea is to facilitate efficient retrieval of the objects representing the queue devices and matrix mdevs as well as to verify that a queue assigned to a matrix mdev is bound to the driver. The links will be created as follows: * When the queue device is probed, if its APQN is assigned to a matrix mdev, the structures representing the queue device and the matrix mdev will be linked. * When an adapter or domain is assigned to a matrix mdev, for each new APQN assigned that references a queue device bound to the vfio_ap device driver, the structures representing the queue device and the matrix mdev will be linked. The links will be removed as follows: * When the queue device is removed, if its APQN is assigned to a matrix mdev, the link from the structure representing the matrix mdev to the structure representing the queue will be removed. Since the storage allocated for the vfio_ap_queue will be freed, there is no need to remove the link to the matrix_mdev to which the queue's APQN is assigned. * When an adapter or domain is unassigned from a matrix mdev, for each APQN unassigned that references a queue device bound to the vfio_ap device driver, the structures representing the queue device and the matrix mdev will be unlinked. * When an mdev is removed, the link from any queues assigned to the mdev to the mdev will be removed. Signed-off-by: Tony Krowiak <akrowiak@linux.ibm.com> Reviewed-by: Halil Pasic <pasic@linux.ibm.com> Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
| * | | | | s390/vfio-ap: move probe and remove callbacks to vfio_ap_ops.cTony Krowiak2022-07-193-120/+102
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Let's move the probe and remove callbacks into the vfio_ap_ops.c file to keep all code related to managing queues in a single file. This way, all functions related to queue management can be removed from the vfio_ap_private.h header file defining the public interfaces for the vfio_ap device driver. Signed-off-by: Tony Krowiak <akrowiak@linux.ibm.com> Reviewed-by: Halil Pasic <pasic@linux.ibm.com> Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
| * | | | | s390/vfio-ap: use new AP bus interface to search for queue devicesTony Krowiak2022-07-191-14/+9
| |/ / / / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch refactors the vfio_ap device driver to use the AP bus's ap_get_qdev() function to retrieve the vfio_ap_queue struct containing information about a queue that is bound to the vfio_ap device driver. The bus's ap_get_qdev() function retrieves the queue device from a hashtable keyed by APQN. This is much more efficient than looping over the list of devices attached to the AP bus by several orders of magnitude. Signed-off-by: Tony Krowiak <akrowiak@linux.ibm.com> Reviewed-by: Halil Pasic <pasic@linux.ibm.com> Reviewed-by: Jason J. Herne <jjherne@linux.ibm.com> Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
* | | | | Merge tag 'vfio-v6.0-rc1' of https://github.com/awilliam/linux-vfioLinus Torvalds2022-08-0610-321/+293
|\ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull VFIO updates from Alex Williamson: - Cleanup use of extern in function prototypes (Alex Williamson) - Simplify bus_type usage and convert to device IOMMU interfaces (Robin Murphy) - Check missed return value and fix comment typos (Bo Liu) - Split migration ops from device ops and fix races in mlx5 migration support (Yishai Hadas) - Fix missed return value check in noiommu support (Liam Ni) - Hardening to clear buffer pointer to avoid use-after-free (Schspa Shi) - Remove requirement that only the same mm can unmap a previously mapped range (Li Zhe) - Adjust semaphore release vs device open counter (Yi Liu) - Remove unused arg from SPAPR support code (Deming Wang) - Rework vfio-ccw driver to better fit new mdev framework (Eric Farman, Michael Kawano) - Replace DMA unmap notifier with callbacks (Jason Gunthorpe) - Clarify SPAPR support comment relative to iommu_ops (Alexey Kardashevskiy) - Revise page pinning API towards compatibility with future iommufd support (Nicolin Chen) - Resolve issues in vfio-ccw, including use of DMA unmap callback (Eric Farman) * tag 'vfio-v6.0-rc1' of https://github.com/awilliam/linux-vfio: (40 commits) vfio/pci: fix the wrong word vfio/ccw: Check return code from subchannel quiesce vfio/ccw: Remove FSM Close from remove handlers vfio/ccw: Add length to DMA_UNMAP checks vfio: Replace phys_pfn with pages for vfio_pin_pages() vfio/ccw: Add kmap_local_page() for memcpy vfio: Rename user_iova of vfio_dma_rw() vfio/ccw: Change pa_pfn list to pa_iova list vfio/ap: Change saved_pfn to saved_iova vfio: Pass in starting IOVA to vfio_pin/unpin_pages API vfio/ccw: Only pass in contiguous pages vfio/ap: Pass in physical address of ind to ap_aqic() drm/i915/gvt: Replace roundup with DIV_ROUND_UP vfio: Make vfio_unpin_pages() return void vfio/spapr_tce: Fix the comment vfio: Replace the iommu notifier with a device list vfio: Replace the DMA unmapping notifier with a callback vfio/ccw: Move FSM open/close to MDEV open/close vfio/ccw: Refactor vfio_ccw_mdev_reset vfio/ccw: Create a CLOSE FSM event ...
| * | | | | vfio/ccw: Check return code from subchannel quiesceEric Farman2022-08-011-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If a subchannel is busy when a close is performed, the subchannel needs to be quiesced and left nice and tidy, so nothing unexpected (like a solicited interrupt) shows up while in the closed state. Unfortunately, the return code from this call isn't checked, so any busy subchannel is treated as a failing one. Fix that, so that the close on a busy subchannel happens normally. Signed-off-by: Eric Farman <farman@linux.ibm.com> Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Link: https://lore.kernel.org/r/20220728204914.2420989-4-farman@linux.ibm.com Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
| * | | | | vfio/ccw: Remove FSM Close from remove handlersEric Farman2022-08-012-3/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Now that neither vfio_ccw_sch_probe() nor vfio_ccw_mdev_probe() affect the FSM state, it doesn't make sense for their _remove() counterparts try to revert things in this way. Since the FSM open and close are handled alongside MDEV open/close, these are unnecessary. Signed-off-by: Eric Farman <farman@linux.ibm.com> Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Link: https://lore.kernel.org/r/20220728204914.2420989-3-farman@linux.ibm.com Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
| * | | | | vfio/ccw: Add length to DMA_UNMAP checksEric Farman2022-08-013-7/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | As pointed out with the simplification of the VFIO_IOMMU_NOTIFY_DMA_UNMAP notifier [1], the length parameter was never used to check against the pinned pages. Let's correct that, and see if a page is within the affected range instead of simply the first page of the range. [1] https://lore.kernel.org/kvm/20220720170457.39cda0d0.alex.williamson@redhat.com/ Signed-off-by: Eric Farman <farman@linux.ibm.com> Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Link: https://lore.kernel.org/r/20220728204914.2420989-2-farman@linux.ibm.com Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
| * | | | | vfio: Replace phys_pfn with pages for vfio_pin_pages()Nicolin Chen2022-07-252-13/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Most of the callers of vfio_pin_pages() want "struct page *" and the low-level mm code to pin pages returns a list of "struct page *" too. So there's no gain in converting "struct page *" to PFN in between. Replace the output parameter "phys_pfn" list with a "pages" list, to simplify callers. This also allows us to replace the vfio_iommu_type1 implementation with a more efficient one. And drop the pfn_valid check in the gvt code, as there is no need to do such a check at a page-backed struct page pointer. For now, also update vfio_iommu_type1 to fit this new parameter too. Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Kirti Wankhede <kwankhede@nvidia.com> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Reviewed-by: Kevin Tian <kevin.tian@intel.com> Acked-by: Eric Farman <farman@linux.ibm.com> Tested-by: Terrence Xu <terrence.xu@intel.com> Tested-by: Eric Farman <farman@linux.ibm.com> Signed-off-by: Nicolin Chen <nicolinc@nvidia.com> Link: https://lore.kernel.org/r/20220723020256.30081-11-nicolinc@nvidia.com Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
| * | | | | vfio/ccw: Add kmap_local_page() for memcpyNicolin Chen2022-07-251-3/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | A PFN is not secure enough to promise that the memory is not IO. And direct access via memcpy() that only handles CPU memory will crash on S390 if the PFN is an IO PFN, as we have to use the memcpy_to/fromio() that uses the special S390 IO access instructions. On the other hand, a "struct page *" is always a CPU coherent thing that fits memcpy(). Also, casting a PFN to "void *" for memcpy() is not a proper practice, kmap_local_page() is the correct API to call here, though S390 doesn't use highmem, which means kmap_local_page() is a NOP. There's a following patch changing the vfio_pin_pages() API to return a list of "struct page *" instead of PFNs. It will block any IO memory from ever getting into this call path, for such a security purpose. In this patch, add kmap_local_page() to prepare for that. Suggested-by: Jason Gunthorpe <jgg@nvidia.com> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Acked-by: Eric Farman <farman@linux.ibm.com> Tested-by: Eric Farman <farman@linux.ibm.com> Signed-off-by: Nicolin Chen <nicolinc@nvidia.com> Link: https://lore.kernel.org/r/20220723020256.30081-10-nicolinc@nvidia.com Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
| * | | | | vfio/ccw: Change pa_pfn list to pa_iova listNicolin Chen2022-07-251-71/+64
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The vfio_ccw_cp code maintains both iova and its PFN list because the vfio_pin/unpin_pages API wanted pfn list. Since vfio_pin/unpin_pages() now accept "iova", change to maintain only pa_iova list and rename all "pfn_array" strings to "page_array", so as to simplify the code. Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Reviewed-by: Eric Farman <farman@linux.ibm.com> Tested-by: Eric Farman <farman@linux.ibm.com> Signed-off-by: Nicolin Chen <nicolinc@nvidia.com> Link: https://lore.kernel.org/r/20220723020256.30081-8-nicolinc@nvidia.com Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
| * | | | | vfio/ap: Change saved_pfn to saved_iovaNicolin Chen2022-07-252-27/+19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The vfio_ap_ops code maintains both nib address and its PFN, which is redundant, merely because vfio_pin/unpin_pages API wanted pfn. Since vfio_pin/unpin_pages() now accept "iova", change "saved_pfn" to "saved_iova" and remove pfn in the vfio_ap_validate_nib(). Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Reviewed-by: Tony Krowiak <akrowiak@linux.ibm.com> Tested-by: Eric Farman <farman@linux.ibm.com> Signed-off-by: Nicolin Chen <nicolinc@nvidia.com> Link: https://lore.kernel.org/r/20220723020256.30081-7-nicolinc@nvidia.com Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
| * | | | | vfio: Pass in starting IOVA to vfio_pin/unpin_pages APINicolin Chen2022-07-252-7/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The vfio_pin/unpin_pages() so far accepted arrays of PFNs of user IOVA. Among all three callers, there was only one caller possibly passing in a non-contiguous PFN list, which is now ensured to have contiguous PFN inputs too. Pass in the starting address with "iova" alone to simplify things, so callers no longer need to maintain a PFN list or to pin/unpin one page at a time. This also allows VFIO to use more efficient implementations of pin/unpin_pages. For now, also update vfio_iommu_type1 to fit this new parameter too, while keeping its input intact (being user_iova) since we don't want to spend too much effort swapping its parameters and local variables at that level. Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Kirti Wankhede <kwankhede@nvidia.com> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Reviewed-by: Kevin Tian <kevin.tian@intel.com> Reviewed-by: Tony Krowiak <akrowiak@linux.ibm.com> Acked-by: Eric Farman <farman@linux.ibm.com> Tested-by: Terrence Xu <terrence.xu@intel.com> Tested-by: Eric Farman <farman@linux.ibm.com> Signed-off-by: Nicolin Chen <nicolinc@nvidia.com> Link: https://lore.kernel.org/r/20220723020256.30081-6-nicolinc@nvidia.com Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
| * | | | | vfio/ccw: Only pass in contiguous pagesNicolin Chen2022-07-231-14/+56
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This driver is the only caller of vfio_pin/unpin_pages that might pass in a non-contiguous PFN list, but in many cases it has a contiguous PFN list to process. So letting VFIO API handle a non-contiguous PFN list is actually counterproductive. Add a pair of simple loops to pass in contiguous PFNs only, to have an efficient implementation in VFIO. Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Reviewed-by: Eric Farman <farman@linux.ibm.com> Tested-by: Eric Farman <farman@linux.ibm.com> Signed-off-by: Nicolin Chen <nicolinc@nvidia.com> Link: https://lore.kernel.org/r/20220723020256.30081-5-nicolinc@nvidia.com Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
| * | | | | vfio/ap: Pass in physical address of ind to ap_aqic()Nicolin Chen2022-07-232-4/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The ap_aqic() is called by vfio_ap_irq_enable() where it passes in a virt value that's casted from a physical address "h_nib". Inside the ap_aqic(), it does virt_to_phys() again. Since ap_aqic() needs a physical address, let's just pass in a pa of ind directly. So change the "ind" to "pa_ind". Reviewed-by: Harald Freudenberger <freude@linux.ibm.com> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Tested-by: Eric Farman <farman@linux.ibm.com> Signed-off-by: Nicolin Chen <nicolinc@nvidia.com> Link: https://lore.kernel.org/r/20220723020256.30081-4-nicolinc@nvidia.com Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
| * | | | | vfio: Replace the DMA unmapping notifier with a callbackJason Gunthorpe2022-07-204-81/+16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Instead of having drivers register the notifier with explicit code just have them provide a dma_unmap callback op in their driver ops and rely on the core code to wire it up. Suggested-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Kevin Tian <kevin.tian@intel.com> Reviewed-by: Tony Krowiak <akrowiak@linux.ibm.com> Reviewed-by: Eric Farman <farman@linux.ibm.com> Reviewed-by: Zhenyu Wang <zhenyuw@linux.intel.com> Signed-off-by: Jason Gunthorpe <jgg@nvidia.com> Link: https://lore.kernel.org/r/1-v4-681e038e30fd+78-vfio_unmap_notif_jgg@nvidia.com Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
| * | | | | vfio/ccw: Move FSM open/close to MDEV open/closeEric Farman2022-07-073-32/+39
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Part of the confusion that has existed is the FSM lifecycle of subchannels between the common CSS driver and the vfio-ccw driver. During configuration, the FSM state goes from NOT_OPER to STANDBY to IDLE, but then back to NOT_OPER. For example: vfio_ccw_sch_probe: VFIO_CCW_STATE_NOT_OPER vfio_ccw_sch_probe: VFIO_CCW_STATE_STANDBY vfio_ccw_mdev_probe: VFIO_CCW_STATE_IDLE vfio_ccw_mdev_remove: VFIO_CCW_STATE_NOT_OPER vfio_ccw_sch_remove: VFIO_CCW_STATE_NOT_OPER vfio_ccw_sch_shutdown: VFIO_CCW_STATE_NOT_OPER Rearrange the open/close events to align with the mdev open/close, to better manage the memory and state of the devices as time progresses. Specifically, make mdev_open() perform the FSM open, and mdev_close() perform the FSM close instead of reset (which is both close and open). This makes the NOT_OPER state a dead-end path, indicating the device is probably not recoverable without fully probing and re-configuring the device. This has the nice side-effect of removing a number of special-cases where the FSM state is managed outside of the FSM itself (such as the aforementioned mdev_close() routine). Suggested-by: Jason Gunthorpe <jgg@nvidia.com> Signed-off-by: Eric Farman <farman@linux.ibm.com> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com> Link: https://lore.kernel.org/r/20220707135737.720765-12-farman@linux.ibm.com Signed-off-by: Alex Williamson <alex.williamson@redhat.com>