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path: root/drivers/virtio/virtio_mem.c
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2020-12-18virtio-mem: Big Block Mode (BBM) - safe memory hotunplugDavid Hildenbrand
Let's add a safe mechanism to unplug memory, avoiding long/endless loops when trying to offline memory - similar to in SBM. Fake-offline all memory (via alloc_contig_range()) before trying to offline+remove it. Use this mode as default, but allow to enable the other mode explicitly (which could give better memory hotunplug guarantees in some environments). The "unsafe" mode can be enabled e.g., via virtio_mem.bbm_safe_unplug=0 on the cmdline. Reviewed-by: Wei Yang <richard.weiyang@linux.alibaba.com> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Jason Wang <jasowang@redhat.com> Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: Oscar Salvador <osalvador@suse.de> Cc: Wei Yang <richard.weiyang@linux.alibaba.com> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: David Hildenbrand <david@redhat.com> Link: https://lore.kernel.org/r/20201112133815.13332-30-david@redhat.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-12-18virtio-mem: Big Block Mode (BBM) - basic memory hotunplugDavid Hildenbrand
Let's try to unplug completely offline big blocks first. Then, (if enabled via unplug_offline) try to offline and remove whole big blocks. No locking necessary - we can deal with concurrent onlining/offlining just fine. Note1: This is sub-optimal and might be dangerous in some environments: we could end up in an infinite loop when offlining (e.g., long-term pinnings), similar as with DIMMs. We'll introduce safe memory hotunplug via fake-offlining next, and use this basic mode only when explicitly enabled. Note2: Without ZONE_MOVABLE, memory unplug will be extremely unreliable with bigger block sizes. Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Jason Wang <jasowang@redhat.com> Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: Oscar Salvador <osalvador@suse.de> Cc: Wei Yang <richard.weiyang@linux.alibaba.com> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: David Hildenbrand <david@redhat.com> Link: https://lore.kernel.org/r/20201112133815.13332-29-david@redhat.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-12-18virtio-mem: allow to force Big Block Mode (BBM) and set the big block sizeDavid Hildenbrand
Let's allow to force BBM, even if subblocks would be possible. Take care of properly calculating the first big block id, because the start address might no longer be aligned to the big block size. Also, allow to manually configure the size of Big Blocks. Reviewed-by: Wei Yang <richard.weiyang@linux.alibaba.com> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Jason Wang <jasowang@redhat.com> Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: Oscar Salvador <osalvador@suse.de> Cc: Wei Yang <richard.weiyang@linux.alibaba.com> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: David Hildenbrand <david@redhat.com> Link: https://lore.kernel.org/r/20201112133815.13332-27-david@redhat.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-12-18virtio-mem: Big Block Mode (BBM) memory hotplugDavid Hildenbrand
Currently, we do not support device block sizes that exceed the Linux memory block size. For example, having a device block size of 1 GiB (e.g., gigantic pages in the hypervisor) won't work with 128 MiB Linux memory blocks. Let's implement Big Block Mode (BBM), whereby we add/remove at least one Linux memory block at a time. With a 1 GiB device block size, a Big Block (BB) will cover 8 Linux memory blocks. We'll keep registering the online_page_callback machinery, it will be used for safe memory hotunplug in BBM next. Note: BBM is properly prepared for variable-sized Linux memory blocks that we might see in the future. So we won't care how many Linux memory blocks a big block actually spans, and how the memory notifier is called. Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Jason Wang <jasowang@redhat.com> Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: Oscar Salvador <osalvador@suse.de> Cc: Wei Yang <richard.weiyang@linux.alibaba.com> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: David Hildenbrand <david@redhat.com> Link: https://lore.kernel.org/r/20201112133815.13332-26-david@redhat.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-12-18virtio-mem: factor out adding/removing memory from LinuxDavid Hildenbrand
Let's use wrappers for the low-level functions that dev_dbg/dev_warn and work on addr + size, such that we can reuse them for adding/removing in other granularity. We only warn when adding memory failed, because that's something to pay attention to. We won't warn when removing failed, we'll reuse that in racy context soon (and we do have proper BUG_ON() statements in the current cases where it must never happen). Reviewed-by: Wei Yang <richard.weiyang@linux.alibaba.com> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Jason Wang <jasowang@redhat.com> Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com> Signed-off-by: David Hildenbrand <david@redhat.com> Link: https://lore.kernel.org/r/20201112133815.13332-25-david@redhat.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-12-18virtio-mem: memory notifier callbacks are specific to Sub Block Mode (SBM)David Hildenbrand
Let's rename accordingly. Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Jason Wang <jasowang@redhat.com> Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com> Signed-off-by: David Hildenbrand <david@redhat.com> Link: https://lore.kernel.org/r/20201112133815.13332-24-david@redhat.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-12-18virito-mem: existing (un)plug functions are specific to Sub Block Mode (SBM)David Hildenbrand
Let's rename them accordingly. virtio_mem_plug_request() and virtio_mem_unplug_request() will be handled separately. Reviewed-by: Wei Yang <richard.weiyang@linux.alibaba.com> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Jason Wang <jasowang@redhat.com> Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com> Signed-off-by: David Hildenbrand <david@redhat.com> Link: https://lore.kernel.org/r/20201112133815.13332-23-david@redhat.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-12-18virtio-mem: memory block ids are specific to Sub Block Mode (SBM)David Hildenbrand
Let's move first_mb_id/next_mb_id/last_usable_mb_id accordingly. Reviewed-by: Wei Yang <richard.weiyang@linux.alibaba.com> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Jason Wang <jasowang@redhat.com> Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com> Signed-off-by: David Hildenbrand <david@redhat.com> Link: https://lore.kernel.org/r/20201112133815.13332-22-david@redhat.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-12-18virtio-mem: nb_sb_per_mb and subblock_size are specific to Sub Block Mode (SBM)David Hildenbrand
Let's rename to "sbs_per_mb" and "sb_size" and move accordingly. Reviewed-by: Wei Yang <richard.weiyang@linux.alibaba.com> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Jason Wang <jasowang@redhat.com> Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com> Signed-off-by: David Hildenbrand <david@redhat.com> Link: https://lore.kernel.org/r/20201112133815.13332-21-david@redhat.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-12-18virito-mem: subblock states are specific to Sub Block Mode (SBM)David Hildenbrand
Let's rename and move accordingly. While at it, rename sb_bitmap to "sb_states". Reviewed-by: Wei Yang <richard.weiyang@linux.alibaba.com> Reviewed-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Jason Wang <jasowang@redhat.com> Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com> Signed-off-by: David Hildenbrand <david@redhat.com> Link: https://lore.kernel.org/r/20201112133815.13332-20-david@redhat.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-12-18virtio-mem: memory block states are specific to Sub Block Mode (SBM)David Hildenbrand
let's use a new "sbm" sub-struct to hold SBM-specific state and rename + move applicable definitions, functions, and variables (related to memory block states). While at it: - Drop the "_STATE" part from memory block states - Rename "nb_mb_state" to "mb_count" - "set_mb_state" / "get_mb_state" vs. "mb_set_state" / "mb_get_state" - Don't use lengthy "enum virtio_mem_smb_mb_state", simply use "uint8_t" Reviewed-by: Wei Yang <richard.weiyang@linux.alibaba.com> Reviewed-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Jason Wang <jasowang@redhat.com> Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com> Signed-off-by: David Hildenbrand <david@redhat.com> Link: https://lore.kernel.org/r/20201112133815.13332-19-david@redhat.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-12-18virito-mem: document Sub Block Mode (SBM)David Hildenbrand
Let's add some documentation for the current mode - Sub Block Mode (SBM) - to prepare for a new mode - Big Block Mode (BBM). Follow-up patches will properly factor out the existing Sub Block Mode (SBM) and implement Big Block Mode (BBM). Reviewed-by: Wei Yang <richard.weiyang@linux.alibaba.com> Reviewed-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Jason Wang <jasowang@redhat.com> Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com> Signed-off-by: David Hildenbrand <david@redhat.com> Link: https://lore.kernel.org/r/20201112133815.13332-18-david@redhat.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-12-18virtio-mem: generalize handling when memory is getting onlined deferredDavid Hildenbrand
We don't want to add too much memory when it's not getting onlined immediately, to avoid running OOM. Generalize the handling, to avoid making use of memory block states. Use a threshold of 1 GiB for now. Properly adjust the offline size when adding/removing memory. As we are not always protected by a lock when touching the offline size, use an atomic64_t. We don't care about races (e.g., someone offlining memory while we are adding more), only about consistent values. (1 GiB needs a memmap of ~16MiB - which sounds reasonable even for setups with little boot memory and (possibly) one virtio-mem device per node) We don't want to retrigger when onlining is caused immediately by our action (e.g., adding memory which immediately gets onlined), so use a flag to indicate if the workqueue is active and use that as an indicator whether to trigger a retry. This will also be especially relevant for Big Block Mode (BBM), whereby we might re-online memory in case offlining of another memory block failed. Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Jason Wang <jasowang@redhat.com> Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com> Signed-off-by: David Hildenbrand <david@redhat.com> Link: https://lore.kernel.org/r/20201112133815.13332-17-david@redhat.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-12-18virtio-mem: don't always trigger the workqueue when offlining memoryDavid Hildenbrand
Let's trigger from offlining code only when we're not allowed to unplug online memory. Handle the other case (memmap possibly freeing up another memory block) when actually removing memory. We now also properly handle the case when removing already offline memory blocks via virtio_mem_mb_remove(). When removing via virtio_mem_remove(), when unloading the driver, virtio_mem_retry() is a NOP and safe to use. While at it, move retry handling when offlining out of virtio_mem_notify_offline(), to share it with Big Block Mode (BBM) soon. This is a preparation for Big Block Mode (BBM), whereby we can see some temporary offlining of memory blocks without actually making progress. Imagine you have a Big Block that spans to Linux memory blocks. Assume the first Linux memory blocks has no unmovable data on it. When we would call offline_and_remove_memory() on the big block, we would 1. Try to offline the first block. Works, notifiers triggered. virtio_mem_retry() called. 2. Try to offline the second block. Does not work. 3. Re-online first block. 4. Exit to main loop, exit workqueue. 5. Retry immediately (due to virtio_mem_retry()), go to 1. The result are endless retries. Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Jason Wang <jasowang@redhat.com> Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com> Signed-off-by: David Hildenbrand <david@redhat.com> Link: https://lore.kernel.org/r/20201112133815.13332-16-david@redhat.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-12-18virtio-mem: drop last_mb_idDavid Hildenbrand
No longer used, let's drop it. Reviewed-by: Wei Yang <richard.weiyang@linux.alibaba.com> Reviewed-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Jason Wang <jasowang@redhat.com> Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com> Signed-off-by: David Hildenbrand <david@redhat.com> Link: https://lore.kernel.org/r/20201112133815.13332-15-david@redhat.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-12-18virtio-mem: generalize virtio_mem_overlaps_range()David Hildenbrand
Avoid using memory block ids. While at it, use uint64_t for address/size. This is a preparation for Big Block Mode (BBM). Reviewed-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Jason Wang <jasowang@redhat.com> Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com> Signed-off-by: David Hildenbrand <david@redhat.com> Link: https://lore.kernel.org/r/20201112133815.13332-14-david@redhat.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-12-18virtio-mem: generalize virtio_mem_owned_mb()David Hildenbrand
Avoid using memory block ids. Rename it to virtio_mem_contains_range(). This is a preparation for Big Block Mode (BBM). Reviewed-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Jason Wang <jasowang@redhat.com> Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com> Signed-off-by: David Hildenbrand <david@redhat.com> Link: https://lore.kernel.org/r/20201112133815.13332-13-david@redhat.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-12-18virtio-mem: generalize check for added memoryDavid Hildenbrand
Let's check by traversing busy system RAM resources instead, to avoid relying on memory block states. Don't use walk_system_ram_range(), as that works on pages and we want to use the bare addresses we have easily at hand. This is a preparation for Big Block Mode (BBM), which won't have memory block states. Reviewed-by: Wei Yang <richard.weiyang@linux.alibaba.com> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Jason Wang <jasowang@redhat.com> Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com> Signed-off-by: David Hildenbrand <david@redhat.com> Link: https://lore.kernel.org/r/20201112133815.13332-12-david@redhat.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-12-18virtio-mem: retry fake-offlining via alloc_contig_range() on ZONE_MOVABLEDavid Hildenbrand
ZONE_MOVABLE is supposed to give some guarantees, yet, alloc_contig_range() isn't prepared to properly deal with some racy cases properly (e.g., temporary page pinning when exiting processed, PCP). Retry 5 times for now. There is certainly room for improvement in the future. Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Jason Wang <jasowang@redhat.com> Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com> Signed-off-by: David Hildenbrand <david@redhat.com> Link: https://lore.kernel.org/r/20201112133815.13332-11-david@redhat.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-12-18virtio-mem: factor out handling of fake-offline pages in memory notifierDavid Hildenbrand
Let's factor out the core pieces and place the implementation next to virtio_mem_fake_offline(). We'll reuse this functionality soon. Reviewed-by: Wei Yang <richard.weiyang@linux.alibaba.com> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Jason Wang <jasowang@redhat.com> Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com> Signed-off-by: David Hildenbrand <david@redhat.com> Link: https://lore.kernel.org/r/20201112133815.13332-10-david@redhat.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-12-18virtio-mem: factor out fake-offlining into virtio_mem_fake_offline()David Hildenbrand
... which now matches virtio_mem_fake_online(). We'll reuse this functionality soon. Reviewed-by: Wei Yang <richard.weiyang@linux.alibaba.com> Reviewed-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Jason Wang <jasowang@redhat.com> Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com> Signed-off-by: David Hildenbrand <david@redhat.com> Link: https://lore.kernel.org/r/20201112133815.13332-9-david@redhat.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-12-18virtio-mem: print debug messages from virtio_mem_send_*_request()David Hildenbrand
Let's move the existing dev_dbg() into the functions, print if something went wrong, and also print for virtio_mem_send_unplug_all_request(). Reviewed-by: Wei Yang <richard.weiyang@linux.alibaba.com> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Jason Wang <jasowang@redhat.com> Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com> Signed-off-by: David Hildenbrand <david@redhat.com> Link: https://lore.kernel.org/r/20201112133815.13332-8-david@redhat.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-12-18virtio-mem: factor out calculation of the bit number within the subblock bitmapDavid Hildenbrand
The calculation is already complicated enough, let's limit it to one location. Reviewed-by: Wei Yang <richard.weiyang@linux.alibaba.com> Reviewed-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Jason Wang <jasowang@redhat.com> Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com> Signed-off-by: David Hildenbrand <david@redhat.com> Link: https://lore.kernel.org/r/20201112133815.13332-7-david@redhat.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-12-18virtio-mem: use "unsigned long" for nr_pages when fake onlining/offliningDavid Hildenbrand
No harm done, but let's be consistent. Reviewed-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com> Reviewed-by: Wei Yang <richard.weiyang@linux.alibaba.com> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Jason Wang <jasowang@redhat.com> Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com> Signed-off-by: David Hildenbrand <david@redhat.com> Link: https://lore.kernel.org/r/20201112133815.13332-6-david@redhat.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-12-18virtio-mem: drop rc2 in virtio_mem_mb_plug_and_add()David Hildenbrand
We can drop rc2, we don't actually need the value. Reviewed-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com> Reviewed-by: Wei Yang <richard.weiyang@linux.alibaba.com> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Jason Wang <jasowang@redhat.com> Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com> Signed-off-by: David Hildenbrand <david@redhat.com> Link: https://lore.kernel.org/r/20201112133815.13332-5-david@redhat.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-12-18virtio-mem: simplify MAX_ORDER - 1 / pageblock_order handlingDavid Hildenbrand
Let's use pageblock_nr_pages and MAX_ORDER_NR_PAGES instead where possible to simplify. Add a comment why we have that restriction for now. Reviewed-by: Wei Yang <richard.weiyang@linux.alibaba.com> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Jason Wang <jasowang@redhat.com> Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com> Signed-off-by: David Hildenbrand <david@redhat.com> Link: https://lore.kernel.org/r/20201112133815.13332-4-david@redhat.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-12-18virtio-mem: more precise calculation in virtio_mem_mb_state_prepare_next_mb()David Hildenbrand
We actually need one byte less (next_mb_id is exclusive, first_mb_id is inclusive). While at it, compact the code. Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Jason Wang <jasowang@redhat.com> Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com> Signed-off-by: David Hildenbrand <david@redhat.com> Link: https://lore.kernel.org/r/20201112133815.13332-3-david@redhat.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-12-18virtio-mem: determine nid only once using memory_add_physaddr_to_nid()David Hildenbrand
Let's determine the target nid only once in case we have none specified - usually, we'll end up with node 0 either way. Reviewed-by: Wei Yang <richard.weiyang@linux.alibaba.com> Reviewed-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Jason Wang <jasowang@redhat.com> Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com> Signed-off-by: David Hildenbrand <david@redhat.com> Link: https://lore.kernel.org/r/20201112133815.13332-2-david@redhat.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-10-23Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhostLinus Torvalds
Pull virtio updates from Michael Tsirkin: "vhost, vdpa, and virtio cleanups and fixes A very quiet cycle, no new features" * tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost: MAINTAINERS: add URL for virtio-mem vhost_vdpa: remove unnecessary spin_lock in vhost_vring_call vringh: fix __vringh_iov() when riov and wiov are different vdpa/mlx5: Setup driver only if VIRTIO_CONFIG_S_DRIVER_OK s390: virtio: PV needs VIRTIO I/O device protection virtio: let arch advertise guest's memory access restrictions vhost_vdpa: Fix duplicate included kernel.h vhost: reduce stack usage in log_used virtio-mem: Constify mem_id_table virtio_input: Constify id_table virtio-balloon: Constify id_table vdpa/mlx5: Fix failure to bring link up vdpa/mlx5: Make use of a specific 16 bit endianness API
2020-10-21virtio-mem: Constify mem_id_tableRikard Falkeborn
mem_id_table is not modified, so make it const to allow the compiler to put it in read-only memory. Signed-off-by: Rikard Falkeborn <rikard.falkeborn@gmail.com> Link: https://lore.kernel.org/r/20200911203509.26505-4-rikard.falkeborn@gmail.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Acked-by: David Hildenbrand <david@redhat.com>
2020-10-16virtio-mem: try to merge system ram resourcesDavid Hildenbrand
virtio-mem adds memory in memory block granularity, to be able to remove it in the same granularity again later, and to grow slowly on demand. This, however, results in quite a lot of resources when adding a lot of memory. Resources are effectively stored in a list-based tree. Having a lot of resources not only wastes memory, it also makes traversing that tree more expensive, and makes /proc/iomem explode in size (e.g., requiring kexec-tools to manually merge resources later when e.g., trying to create a kdump header). Before this patch, we get (/proc/iomem) when hotplugging 2G via virtio-mem on x86-64: [...] 100000000-13fffffff : System RAM 140000000-33fffffff : virtio0 140000000-147ffffff : System RAM (virtio_mem) 148000000-14fffffff : System RAM (virtio_mem) 150000000-157ffffff : System RAM (virtio_mem) 158000000-15fffffff : System RAM (virtio_mem) 160000000-167ffffff : System RAM (virtio_mem) 168000000-16fffffff : System RAM (virtio_mem) 170000000-177ffffff : System RAM (virtio_mem) 178000000-17fffffff : System RAM (virtio_mem) 180000000-187ffffff : System RAM (virtio_mem) 188000000-18fffffff : System RAM (virtio_mem) 190000000-197ffffff : System RAM (virtio_mem) 198000000-19fffffff : System RAM (virtio_mem) 1a0000000-1a7ffffff : System RAM (virtio_mem) 1a8000000-1afffffff : System RAM (virtio_mem) 1b0000000-1b7ffffff : System RAM (virtio_mem) 1b8000000-1bfffffff : System RAM (virtio_mem) 3280000000-32ffffffff : PCI Bus 0000:00 With this patch, we get (/proc/iomem): [...] fffc0000-ffffffff : Reserved 100000000-13fffffff : System RAM 140000000-33fffffff : virtio0 140000000-1bfffffff : System RAM (virtio_mem) 3280000000-32ffffffff : PCI Bus 0000:00 Of course, with more hotplugged memory, it gets worse. When unplugging memory blocks again, try_remove_memory() (via offline_and_remove_memory()) will properly split the resource up again. Signed-off-by: David Hildenbrand <david@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Michael S. Tsirkin <mst@redhat.com> Cc: Jason Wang <jasowang@redhat.com> Cc: Baoquan He <bhe@redhat.com> Cc: Wei Yang <richardw.yang@linux.intel.com> Cc: Anton Blanchard <anton@ozlabs.org> Cc: Ard Biesheuvel <ardb@kernel.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Haiyang Zhang <haiyangz@microsoft.com> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Juergen Gross <jgross@suse.com> Cc: Julien Grall <julien@xen.org> Cc: Kees Cook <keescook@chromium.org> Cc: "K. Y. Srinivasan" <kys@microsoft.com> Cc: Len Brown <lenb@kernel.org> Cc: Leonardo Bras <leobras.c@gmail.com> Cc: Libor Pechacek <lpechacek@suse.cz> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Nathan Lynch <nathanl@linux.ibm.com> Cc: "Oliver O'Halloran" <oohall@gmail.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Pingfan Liu <kernelfans@gmail.com> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: Roger Pau Monné <roger.pau@citrix.com> Cc: Stefano Stabellini <sstabellini@kernel.org> Cc: Stephen Hemminger <sthemmin@microsoft.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: Wei Liu <wei.liu@kernel.org> Link: https://lkml.kernel.org/r/20200911103459.10306-7-david@redhat.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-16mm/memory_hotplug: prepare passing flags to add_memory() and friendsDavid Hildenbrand
We soon want to pass flags, e.g., to mark added System RAM resources. mergeable. Prepare for that. This patch is based on a similar patch by Oscar Salvador: https://lkml.kernel.org/r/20190625075227.15193-3-osalvador@suse.de Signed-off-by: David Hildenbrand <david@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Juergen Gross <jgross@suse.com> # Xen related part Reviewed-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com> Acked-by: Wei Liu <wei.liu@kernel.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Baoquan He <bhe@redhat.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: Len Brown <lenb@kernel.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: Dave Jiang <dave.jiang@intel.com> Cc: "K. Y. Srinivasan" <kys@microsoft.com> Cc: Haiyang Zhang <haiyangz@microsoft.com> Cc: Stephen Hemminger <sthemmin@microsoft.com> Cc: Wei Liu <wei.liu@kernel.org> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: David Hildenbrand <david@redhat.com> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Jason Wang <jasowang@redhat.com> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Stefano Stabellini <sstabellini@kernel.org> Cc: "Oliver O'Halloran" <oohall@gmail.com> Cc: Pingfan Liu <kernelfans@gmail.com> Cc: Nathan Lynch <nathanl@linux.ibm.com> Cc: Libor Pechacek <lpechacek@suse.cz> Cc: Anton Blanchard <anton@ozlabs.org> Cc: Leonardo Bras <leobras.c@gmail.com> Cc: Ard Biesheuvel <ardb@kernel.org> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Julien Grall <julien@xen.org> Cc: Kees Cook <keescook@chromium.org> Cc: Roger Pau Monné <roger.pau@citrix.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Wei Yang <richardw.yang@linux.intel.com> Link: https://lkml.kernel.org/r/20200911103459.10306-5-david@redhat.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-13virtio-mem: don't special-case ZONE_MOVABLEDavid Hildenbrand
When introducing virtio-mem, the semantics of ZONE_MOVABLE were rather unclear, which is why we special-cased ZONE_MOVABLE such that partially plugged blocks would never end up in ZONE_MOVABLE. Now that the semantics are much clearer (and will be documented in a follow-up patch including the new virtio-mem behavior), let's allow to online partially plugged memory blocks to ZONE_MOVABLE and also consider memory blocks that were onlined to ZONE_MOVABLE when unplugging memory. While unplugged memory pages are, in general, unmovable, they can be skipped when offlining memory. virtio-mem only unplugs fairly big chunks (in the megabyte range) and rather tries to shrink the memory region than randomly choosing memory. In theory, if all other pages in the movable zone would be movable, virtio-mem would only shrink that zone and not create any kind of fragmentation. In the future, we might want to remember the zone again and use the information when (un)plugging memory. For now, let's keep it simple. Note: Support for defragmentation is planned, to deal with fragmentation after unplug due to memory chunks within memory blocks that could not get unplugged before (e.g., somebody pinning pages within ZONE_MOVABLE for a longer time). Signed-off-by: David Hildenbrand <david@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Michael S. Tsirkin <mst@redhat.com> Cc: Jason Wang <jasowang@redhat.com> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com> Cc: Baoquan He <bhe@redhat.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Qian Cai <cai@lca.pw> Link: http://lkml.kernel.org/r/20200816125333.7434-6-david@redhat.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-05virtio_mem: convert to LE accessorsMichael S. Tsirkin
Virtio mem is modern-only. Use LE accessors for config space. Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-06-22virtio-mem: add memory via add_memory_driver_managed()David Hildenbrand
Virtio-mem managed memory is always detected and added by the virtio-mem driver, never using something like the firmware-provided memory map. This is the case after an ordinary system reboot, and has to be guaranteed after kexec. Especially, virtio-mem added memory resources can contain inaccessible parts ("unblocked memory blocks"), blindly forwarding them to a kexec kernel is dangerous, as unplugged memory will get accessed (esp. written). Let's use the new way of adding special driver-managed memory introduced in commit 7b7b27214bba ("mm/memory_hotplug: introduce add_memory_driver_managed()"). This will result in no entries in /sys/firmware/memmap ("raw firmware- provided memory map"), the memory resource will be flagged IORESOURCE_MEM_DRIVER_MANAGED (esp., kexec_file_load() will not place kexec images on this memory), and it is exposed as "System RAM (virtio_mem)" in /proc/iomem, so esp. kexec-tools can properly handle it. Example /proc/iomem before this change: [...] 140000000-333ffffff : virtio0 140000000-147ffffff : System RAM 334000000-533ffffff : virtio1 338000000-33fffffff : System RAM 340000000-347ffffff : System RAM 348000000-34fffffff : System RAM [...] Example /proc/iomem after this change: [...] 140000000-333ffffff : virtio0 140000000-147ffffff : System RAM (virtio_mem) 334000000-533ffffff : virtio1 338000000-33fffffff : System RAM (virtio_mem) 340000000-347ffffff : System RAM (virtio_mem) 348000000-34fffffff : System RAM (virtio_mem) [...] Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com> Cc: teawater <teawaterz@linux.alibaba.com> Fixes: 5f1f79bbc9e26 ("virtio-mem: Paravirtualized memory hotplug") Signed-off-by: David Hildenbrand <david@redhat.com> Link: https://lore.kernel.org/r/20200611093518.5737-1-david@redhat.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Reviewed-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
2020-06-22virtio-mem: silence a static checker warningDan Carpenter
Smatch complains that "rc" can be uninitialized if we hit the "break;" statement on the first iteration through the loop. I suspect that this can't happen in real life, but returning a zero literal is cleaner and silence the static checker warning. Fixes: 5f1f79bbc9e2 ("virtio-mem: Paravirtualized memory hotplug") Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Link: https://lore.kernel.org/r/20200610085911.GC5439@mwanda Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-06-09virtio_mem: convert device block size into 64bitMichael S. Tsirkin
If subblock size is large (e.g. 1G) 32 bit math involving it can overflow. Rather than try to catch all instances of that, let's tweak block size to 64 bit. It ripples through UAPI which is an ABI change, but it's not too late to make it, and it will allow supporting >4Gbyte blocks while might become necessary down the road. Fixes: 5f1f79bbc9e26 ("virtio-mem: Paravirtualized memory hotplug") Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Acked-by: David Hildenbrand <david@redhat.com>
2020-06-08virtio-mem: drop unnecessary initializationMichael S. Tsirkin
rc is initialized to -ENIVAL but that's never used. Drop it. Fixes: 5f1f79bbc9e2 ("virtio-mem: Paravirtualized memory hotplug") Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Acked-by: David Hildenbrand <david@redhat.com>
2020-06-04virtio-mem: Don't rely on implicit compiler padding for requestsDavid Hildenbrand
The compiler will add padding after the last member, make that explicit. The size of a request is always 24 bytes. The size of a response always 10 bytes. Add compile-time checks. Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com> Cc: teawater <teawaterz@linux.alibaba.com> Signed-off-by: David Hildenbrand <david@redhat.com> Link: https://lore.kernel.org/r/20200515101402.16597-1-david@redhat.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-06-04virtio-mem: Try to unplug the complete online memory block firstDavid Hildenbrand
Right now, we always try to unplug single subblocks when processing an online memory block. Let's try to unplug the complete online memory block first, in case it is fully plugged and the unplug request is large enough. Fallback to single subblocks in case the memory block cannot get unplugged as a whole. Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com> Signed-off-by: David Hildenbrand <david@redhat.com> Link: https://lore.kernel.org/r/20200507140139.17083-16-david@redhat.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-06-04virtio-mem: Use -ETXTBSY as error code if the device is busyDavid Hildenbrand
Let's be able to distinguish if the device or if memory is busy. Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com> Signed-off-by: David Hildenbrand <david@redhat.com> Link: https://lore.kernel.org/r/20200507140139.17083-15-david@redhat.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-06-04virtio-mem: Unplug subblocks right-to-leftDavid Hildenbrand
We unplug blocks right-to-left, let's also unplug subblocks within a block right-to-left. Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com> Signed-off-by: David Hildenbrand <david@redhat.com> Link: https://lore.kernel.org/r/20200507140139.17083-14-david@redhat.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-06-04virtio-mem: Drop manual check for already present memoryDavid Hildenbrand
Registering our parent resource will fail if any memory is still present (e.g., because somebody unloaded the driver and tries to reload it). No need for the manual check. Move our "unplug all" handling to after registering the resource. Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com> Signed-off-by: David Hildenbrand <david@redhat.com> Link: https://lore.kernel.org/r/20200507140139.17083-13-david@redhat.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-06-04virtio-mem: Add parent resource for all added "System RAM"David Hildenbrand
Let's add a parent resource, named after the virtio device (inspired by drivers/dax/kmem.c). This allows user space to identify which memory belongs to which virtio-mem device. With this change and two virtio-mem devices: :/# cat /proc/iomem 00000000-00000fff : Reserved 00001000-0009fbff : System RAM [...] 140000000-333ffffff : virtio0 140000000-147ffffff : System RAM 148000000-14fffffff : System RAM 150000000-157ffffff : System RAM [...] 334000000-3033ffffff : virtio1 338000000-33fffffff : System RAM 340000000-347ffffff : System RAM 348000000-34fffffff : System RAM [...] Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com> Signed-off-by: David Hildenbrand <david@redhat.com> Link: https://lore.kernel.org/r/20200507140139.17083-12-david@redhat.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Reviewed-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
2020-06-04virtio-mem: Better retry handlingDavid Hildenbrand
Let's start with a retry interval of 5 seconds and double the time until we reach 5 minutes, in case we keep getting errors. Reset the retry interval in case we succeeded. The two main reasons for having to retry are - The hypervisor is busy and cannot process our request - We cannot reach the desired requested_size (esp., not enough memory can get unplugged because we can't allocate any subblocks). Tested-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Jason Wang <jasowang@redhat.com> Cc: Oscar Salvador <osalvador@suse.de> Cc: Michal Hocko <mhocko@kernel.org> Cc: Igor Mammedov <imammedo@redhat.com> Cc: Dave Young <dyoung@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Pavel Tatashin <pasha.tatashin@soleen.com> Cc: Stefan Hajnoczi <stefanha@redhat.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: David Hildenbrand <david@redhat.com> Link: https://lore.kernel.org/r/20200507140139.17083-11-david@redhat.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-06-04virtio-mem: Offline and remove completely unplugged memory blocksDavid Hildenbrand
Let's offline+remove memory blocks once all subblocks are unplugged. We can use the new Linux MM interface for that. As no memory is in use anymore, this shouldn't take a long time and shouldn't fail. There might be corner cases where the offlining could still fail (especially, if another notifier NACKs the offlining request). Acked-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com> Tested-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Jason Wang <jasowang@redhat.com> Cc: Oscar Salvador <osalvador@suse.de> Cc: Michal Hocko <mhocko@kernel.org> Cc: Igor Mammedov <imammedo@redhat.com> Cc: Dave Young <dyoung@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Pavel Tatashin <pasha.tatashin@soleen.com> Cc: Stefan Hajnoczi <stefanha@redhat.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: David Hildenbrand <david@redhat.com> Link: https://lore.kernel.org/r/20200507140139.17083-10-david@redhat.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-06-04virtio-mem: Allow to offline partially unplugged memory blocksDavid Hildenbrand
Dropping the reference count of PageOffline() pages during MEM_GOING_ONLINE allows offlining code to skip them. However, we also have to clear PG_reserved, because PG_reserved pages get detected as unmovable right away. Take care of restoring the reference count when offlining is canceled. Clarify why we don't have to perform any action when unloading the driver. Also, let's add a warning if anybody is still holding a reference to unplugged pages when offlining. Tested-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Jason Wang <jasowang@redhat.com> Cc: Oscar Salvador <osalvador@suse.de> Cc: Michal Hocko <mhocko@kernel.org> Cc: Igor Mammedov <imammedo@redhat.com> Cc: Dave Young <dyoung@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Pavel Tatashin <pasha.tatashin@soleen.com> Cc: Stefan Hajnoczi <stefanha@redhat.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: David Hildenbrand <david@redhat.com> Link: https://lore.kernel.org/r/20200507140139.17083-8-david@redhat.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-06-04virtio-mem: Paravirtualized memory hotunplug part 2David Hildenbrand
We also want to unplug online memory (contained in online memory blocks and, therefore, managed by the buddy), and eventually replug it later. When requested to unplug memory, we use alloc_contig_range() to allocate subblocks in online memory blocks (so we are the owner) and send them to our hypervisor. When requested to plug memory, we can replug such memory using free_contig_range() after asking our hypervisor. We also want to mark all allocated pages PG_offline, so nobody will touch them. To differentiate pages that were never onlined when onlining the memory block from pages allocated via alloc_contig_range(), we use PageDirty(). Based on this flag, virtio_mem_fake_online() can either online the pages for the first time or use free_contig_range(). It is worth noting that there are no guarantees on how much memory can actually get unplugged again. All device memory might completely be fragmented with unmovable data, such that no subblock can get unplugged. We are not touching the ZONE_MOVABLE. If memory is onlined to the ZONE_MOVABLE, it can only get unplugged after that memory was offlined manually by user space. In normal operation, virtio-mem memory is suggested to be onlined to ZONE_NORMAL. In the future, we will try to make unplug more likely to succeed. Add a module parameter to control if online memory shall be touched. As we want to access alloc_contig_range()/free_contig_range() from kernel module context, export the symbols. Note: Whenever virtio-mem uses alloc_contig_range(), all affected pages are on the same node, in the same zone, and contain no holes. Acked-by: Michal Hocko <mhocko@suse.com> # to export contig range allocator API Tested-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Jason Wang <jasowang@redhat.com> Cc: Oscar Salvador <osalvador@suse.de> Cc: Michal Hocko <mhocko@kernel.org> Cc: Igor Mammedov <imammedo@redhat.com> Cc: Dave Young <dyoung@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Pavel Tatashin <pasha.tatashin@soleen.com> Cc: Stefan Hajnoczi <stefanha@redhat.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Mike Rapoport <rppt@linux.ibm.com> Cc: Alexander Duyck <alexander.h.duyck@linux.intel.com> Cc: Alexander Potapenko <glider@google.com> Signed-off-by: David Hildenbrand <david@redhat.com> Link: https://lore.kernel.org/r/20200507140139.17083-6-david@redhat.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-06-04virtio-mem: Paravirtualized memory hotunplug part 1David Hildenbrand
Unplugging subblocks of memory blocks that are offline is easy. All we have to do is watch out for concurrent onlining activity. Tested-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Jason Wang <jasowang@redhat.com> Cc: Oscar Salvador <osalvador@suse.de> Cc: Michal Hocko <mhocko@kernel.org> Cc: Igor Mammedov <imammedo@redhat.com> Cc: Dave Young <dyoung@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Pavel Tatashin <pasha.tatashin@soleen.com> Cc: Stefan Hajnoczi <stefanha@redhat.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: David Hildenbrand <david@redhat.com> Link: https://lore.kernel.org/r/20200507140139.17083-5-david@redhat.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-06-04virtio-mem: Allow to specify an ACPI PXM as nidDavid Hildenbrand
We want to allow to specify (similar as for a DIMM), to which node a virtio-mem device (and, therefore, its memory) belongs. Add a new virtio-mem feature flag and export pxm_to_node, so it can be used in kernel module context. Acked-by: Michal Hocko <mhocko@suse.com> # for the export Acked-by: "Rafael J. Wysocki" <rafael@kernel.org> # for the export Acked-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com> Tested-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Jason Wang <jasowang@redhat.com> Cc: Oscar Salvador <osalvador@suse.de> Cc: Michal Hocko <mhocko@kernel.org> Cc: Igor Mammedov <imammedo@redhat.com> Cc: Dave Young <dyoung@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Pavel Tatashin <pasha.tatashin@soleen.com> Cc: Stefan Hajnoczi <stefanha@redhat.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Len Brown <lenb@kernel.org> Cc: linux-acpi@vger.kernel.org Signed-off-by: David Hildenbrand <david@redhat.com> Link: https://lore.kernel.org/r/20200507140139.17083-4-david@redhat.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com>