mirror of https://gitee.com/openkylin/linux.git
virtio-mem: Big Block Mode (BBM) memory hotplug
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>
This commit is contained in:
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4ba50cd335
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@ -30,12 +30,18 @@ MODULE_PARM_DESC(unplug_online, "Try to unplug online memory");
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/*
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* virtio-mem currently supports the following modes of operation:
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*
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* * Sub Block Mode (SBM): A Linux memory block spans 1..X subblocks (SB). The
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* * Sub Block Mode (SBM): A Linux memory block spans 2..X subblocks (SB). The
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* size of a Sub Block (SB) is determined based on the device block size, the
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* pageblock size, and the maximum allocation granularity of the buddy.
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* Subblocks within a Linux memory block might either be plugged or unplugged.
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* Memory is added/removed to Linux MM in Linux memory block granularity.
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*
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* * Big Block Mode (BBM): A Big Block (BB) spans 1..X Linux memory blocks.
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* Memory is added/removed to Linux MM in Big Block granularity.
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*
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* The mode is determined automatically based on the Linux memory block size
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* and the device block size.
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*
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* User space / core MM (auto onlining) is responsible for onlining added
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* Linux memory blocks - and for selecting a zone. Linux Memory Blocks are
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* always onlined separately, and all memory within a Linux memory block is
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@ -61,6 +67,19 @@ enum virtio_mem_sbm_mb_state {
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VIRTIO_MEM_SBM_MB_COUNT
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};
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/*
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* State of a Big Block (BB) in BBM, covering 1..X Linux memory blocks.
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*/
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enum virtio_mem_bbm_bb_state {
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/* Unplugged, not added to Linux. Can be reused later. */
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VIRTIO_MEM_BBM_BB_UNUSED = 0,
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/* Plugged, not added to Linux. Error on add_memory(). */
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VIRTIO_MEM_BBM_BB_PLUGGED,
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/* Plugged and added to Linux. */
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VIRTIO_MEM_BBM_BB_ADDED,
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VIRTIO_MEM_BBM_BB_COUNT
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};
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struct virtio_mem {
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struct virtio_device *vdev;
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@ -113,47 +132,70 @@ struct virtio_mem {
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atomic64_t offline_size;
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uint64_t offline_threshold;
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struct {
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/* Id of the first memory block of this device. */
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unsigned long first_mb_id;
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/* Id of the last usable memory block of this device. */
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unsigned long last_usable_mb_id;
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/* Id of the next memory bock to prepare when needed. */
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unsigned long next_mb_id;
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/* If set, the driver is in SBM, otherwise in BBM. */
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bool in_sbm;
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/* The subblock size. */
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uint64_t sb_size;
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/* The number of subblocks per Linux memory block. */
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uint32_t sbs_per_mb;
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union {
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struct {
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/* Id of the first memory block of this device. */
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unsigned long first_mb_id;
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/* Id of the last usable memory block of this device. */
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unsigned long last_usable_mb_id;
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/* Id of the next memory bock to prepare when needed. */
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unsigned long next_mb_id;
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/* Summary of all memory block states. */
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unsigned long mb_count[VIRTIO_MEM_SBM_MB_COUNT];
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/* The subblock size. */
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uint64_t sb_size;
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/* The number of subblocks per Linux memory block. */
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uint32_t sbs_per_mb;
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/*
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* One byte state per memory block. Allocated via vmalloc().
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* Resized (alloc+copy+free) on demand.
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*
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* With 128 MiB memory blocks, we have states for 512 GiB of
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* memory in one 4 KiB page.
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*/
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uint8_t *mb_states;
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/* Summary of all memory block states. */
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unsigned long mb_count[VIRTIO_MEM_SBM_MB_COUNT];
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/*
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* Bitmap: one bit per subblock. Allocated similar to
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* sbm.mb_states.
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*
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* A set bit means the corresponding subblock is plugged,
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* otherwise it's unblocked.
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*
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* With 4 MiB subblocks, we manage 128 GiB of memory in one
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* 4 KiB page.
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*/
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unsigned long *sb_states;
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} sbm;
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/*
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* One byte state per memory block. Allocated via
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* vmalloc(). Resized (alloc+copy+free) on demand.
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*
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* With 128 MiB memory blocks, we have states for 512
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* GiB of memory in one 4 KiB page.
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*/
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uint8_t *mb_states;
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/*
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* Bitmap: one bit per subblock. Allocated similar to
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* sbm.mb_states.
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*
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* A set bit means the corresponding subblock is
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* plugged, otherwise it's unblocked.
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*
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* With 4 MiB subblocks, we manage 128 GiB of memory
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* in one 4 KiB page.
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*/
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unsigned long *sb_states;
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} sbm;
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struct {
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/* Id of the first big block of this device. */
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unsigned long first_bb_id;
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/* Id of the last usable big block of this device. */
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unsigned long last_usable_bb_id;
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/* Id of the next device bock to prepare when needed. */
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unsigned long next_bb_id;
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/* Summary of all big block states. */
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unsigned long bb_count[VIRTIO_MEM_BBM_BB_COUNT];
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/* One byte state per big block. See sbm.mb_states. */
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uint8_t *bb_states;
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/* The block size used for plugging/adding/removing. */
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uint64_t bb_size;
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} bbm;
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};
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/*
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* Mutex that protects the sbm.mb_count, sbm.mb_states, and
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* sbm.sb_states.
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* Mutex that protects the sbm.mb_count, sbm.mb_states,
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* sbm.sb_states, bbm.bb_count, and bbm.bb_states
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*
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* When this lock is held the pointers can't change, ONLINE and
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* OFFLINE blocks can't change the state and no subblocks will get
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@ -247,6 +289,24 @@ static unsigned long virtio_mem_mb_id_to_phys(unsigned long mb_id)
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return mb_id * memory_block_size_bytes();
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}
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/*
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* Calculate the big block id of a given address.
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*/
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static unsigned long virtio_mem_phys_to_bb_id(struct virtio_mem *vm,
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uint64_t addr)
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{
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return addr / vm->bbm.bb_size;
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}
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/*
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* Calculate the physical start address of a given big block id.
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*/
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static uint64_t virtio_mem_bb_id_to_phys(struct virtio_mem *vm,
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unsigned long bb_id)
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{
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return bb_id * vm->bbm.bb_size;
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}
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/*
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* Calculate the subblock id of a given address.
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*/
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@ -259,6 +319,67 @@ static unsigned long virtio_mem_phys_to_sb_id(struct virtio_mem *vm,
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return (addr - mb_addr) / vm->sbm.sb_size;
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}
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/*
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* Set the state of a big block, taking care of the state counter.
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*/
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static void virtio_mem_bbm_set_bb_state(struct virtio_mem *vm,
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unsigned long bb_id,
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enum virtio_mem_bbm_bb_state state)
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{
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const unsigned long idx = bb_id - vm->bbm.first_bb_id;
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enum virtio_mem_bbm_bb_state old_state;
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old_state = vm->bbm.bb_states[idx];
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vm->bbm.bb_states[idx] = state;
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BUG_ON(vm->bbm.bb_count[old_state] == 0);
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vm->bbm.bb_count[old_state]--;
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vm->bbm.bb_count[state]++;
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}
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/*
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* Get the state of a big block.
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*/
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static enum virtio_mem_bbm_bb_state virtio_mem_bbm_get_bb_state(struct virtio_mem *vm,
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unsigned long bb_id)
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{
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return vm->bbm.bb_states[bb_id - vm->bbm.first_bb_id];
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}
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/*
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* Prepare the big block state array for the next big block.
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*/
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static int virtio_mem_bbm_bb_states_prepare_next_bb(struct virtio_mem *vm)
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{
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unsigned long old_bytes = vm->bbm.next_bb_id - vm->bbm.first_bb_id;
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unsigned long new_bytes = old_bytes + 1;
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int old_pages = PFN_UP(old_bytes);
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int new_pages = PFN_UP(new_bytes);
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uint8_t *new_array;
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if (vm->bbm.bb_states && old_pages == new_pages)
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return 0;
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new_array = vzalloc(new_pages * PAGE_SIZE);
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if (!new_array)
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return -ENOMEM;
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mutex_lock(&vm->hotplug_mutex);
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if (vm->bbm.bb_states)
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memcpy(new_array, vm->bbm.bb_states, old_pages * PAGE_SIZE);
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vfree(vm->bbm.bb_states);
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vm->bbm.bb_states = new_array;
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mutex_unlock(&vm->hotplug_mutex);
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return 0;
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}
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#define virtio_mem_bbm_for_each_bb(_vm, _bb_id, _state) \
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for (_bb_id = vm->bbm.first_bb_id; \
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_bb_id < vm->bbm.next_bb_id && _vm->bbm.bb_count[_state]; \
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_bb_id++) \
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if (virtio_mem_bbm_get_bb_state(_vm, _bb_id) == _state)
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/*
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* Set the state of a memory block, taking care of the state counter.
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*/
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@ -502,6 +623,17 @@ static int virtio_mem_sbm_add_mb(struct virtio_mem *vm, unsigned long mb_id)
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return virtio_mem_add_memory(vm, addr, size);
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}
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/*
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* See virtio_mem_add_memory(): Try adding a big block.
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*/
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static int virtio_mem_bbm_add_bb(struct virtio_mem *vm, unsigned long bb_id)
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{
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const uint64_t addr = virtio_mem_bb_id_to_phys(vm, bb_id);
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const uint64_t size = vm->bbm.bb_size;
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return virtio_mem_add_memory(vm, addr, size);
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}
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/*
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* Try removing memory from Linux. Will only fail if memory blocks aren't
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* offline.
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@ -729,20 +861,33 @@ static int virtio_mem_memory_notifier_cb(struct notifier_block *nb,
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struct memory_notify *mhp = arg;
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const unsigned long start = PFN_PHYS(mhp->start_pfn);
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const unsigned long size = PFN_PHYS(mhp->nr_pages);
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const unsigned long mb_id = virtio_mem_phys_to_mb_id(start);
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int rc = NOTIFY_OK;
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unsigned long id;
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if (!virtio_mem_overlaps_range(vm, start, size))
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return NOTIFY_DONE;
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/*
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* Memory is onlined/offlined in memory block granularity. We cannot
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* cross virtio-mem device boundaries and memory block boundaries. Bail
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* out if this ever changes.
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*/
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if (WARN_ON_ONCE(size != memory_block_size_bytes() ||
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!IS_ALIGNED(start, memory_block_size_bytes())))
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return NOTIFY_BAD;
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if (vm->in_sbm) {
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id = virtio_mem_phys_to_mb_id(start);
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/*
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* In SBM, we add memory in separate memory blocks - we expect
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* it to be onlined/offlined in the same granularity. Bail out
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* if this ever changes.
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*/
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if (WARN_ON_ONCE(size != memory_block_size_bytes() ||
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!IS_ALIGNED(start, memory_block_size_bytes())))
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return NOTIFY_BAD;
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} else {
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id = virtio_mem_phys_to_bb_id(vm, start);
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/*
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* In BBM, we only care about onlining/offlining happening
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* within a single big block, we don't care about the
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* actual granularity as we don't track individual Linux
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* memory blocks.
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*/
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if (WARN_ON_ONCE(id != virtio_mem_phys_to_bb_id(vm, start + size - 1)))
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return NOTIFY_BAD;
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}
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/*
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* Avoid circular locking lockdep warnings. We lock the mutex
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@ -761,7 +906,8 @@ static int virtio_mem_memory_notifier_cb(struct notifier_block *nb,
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break;
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}
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vm->hotplug_active = true;
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virtio_mem_sbm_notify_going_offline(vm, mb_id);
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if (vm->in_sbm)
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virtio_mem_sbm_notify_going_offline(vm, id);
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break;
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case MEM_GOING_ONLINE:
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mutex_lock(&vm->hotplug_mutex);
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@ -771,10 +917,12 @@ static int virtio_mem_memory_notifier_cb(struct notifier_block *nb,
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break;
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}
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vm->hotplug_active = true;
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rc = virtio_mem_sbm_notify_going_online(vm, mb_id);
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if (vm->in_sbm)
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rc = virtio_mem_sbm_notify_going_online(vm, id);
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break;
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case MEM_OFFLINE:
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virtio_mem_sbm_notify_offline(vm, mb_id);
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if (vm->in_sbm)
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virtio_mem_sbm_notify_offline(vm, id);
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atomic64_add(size, &vm->offline_size);
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/*
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@ -788,7 +936,8 @@ static int virtio_mem_memory_notifier_cb(struct notifier_block *nb,
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mutex_unlock(&vm->hotplug_mutex);
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break;
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case MEM_ONLINE:
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virtio_mem_sbm_notify_online(vm, mb_id);
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if (vm->in_sbm)
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virtio_mem_sbm_notify_online(vm, id);
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atomic64_sub(size, &vm->offline_size);
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/*
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@ -807,7 +956,8 @@ static int virtio_mem_memory_notifier_cb(struct notifier_block *nb,
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case MEM_CANCEL_OFFLINE:
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if (!vm->hotplug_active)
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break;
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virtio_mem_sbm_notify_cancel_offline(vm, mb_id);
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if (vm->in_sbm)
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virtio_mem_sbm_notify_cancel_offline(vm, id);
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vm->hotplug_active = false;
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mutex_unlock(&vm->hotplug_mutex);
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break;
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@ -978,27 +1128,29 @@ static void virtio_mem_fake_offline_cancel_offline(unsigned long pfn,
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static void virtio_mem_online_page_cb(struct page *page, unsigned int order)
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{
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const unsigned long addr = page_to_phys(page);
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const unsigned long mb_id = virtio_mem_phys_to_mb_id(addr);
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unsigned long id, sb_id;
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struct virtio_mem *vm;
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int sb_id;
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bool do_online;
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/*
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* We exploit here that subblocks have at least MAX_ORDER_NR_PAGES.
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* size/alignment and that this callback is is called with such a
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* size/alignment. So we cannot cross subblocks and therefore
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* also not memory blocks.
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*/
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rcu_read_lock();
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list_for_each_entry_rcu(vm, &virtio_mem_devices, next) {
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if (!virtio_mem_contains_range(vm, addr, PFN_PHYS(1 << order)))
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continue;
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sb_id = virtio_mem_phys_to_sb_id(vm, addr);
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/*
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* If plugged, online the pages, otherwise, set them fake
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* offline (PageOffline).
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*/
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if (virtio_mem_sbm_test_sb_plugged(vm, mb_id, sb_id, 1))
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if (vm->in_sbm) {
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/*
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* We exploit here that subblocks have at least
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* MAX_ORDER_NR_PAGES size/alignment - so we cannot
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* cross subblocks within one call.
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*/
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id = virtio_mem_phys_to_mb_id(addr);
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sb_id = virtio_mem_phys_to_sb_id(vm, addr);
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do_online = virtio_mem_sbm_test_sb_plugged(vm, id,
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sb_id, 1);
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} else {
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do_online = true;
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}
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if (do_online)
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generic_online_page(page, order);
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else
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virtio_mem_set_fake_offline(PFN_DOWN(addr), 1 << order,
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@ -1178,6 +1330,32 @@ static int virtio_mem_sbm_unplug_sb(struct virtio_mem *vm, unsigned long mb_id,
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return rc;
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}
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/*
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* Request to unplug a big block.
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*
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* Will not modify the state of the big block.
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*/
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static int virtio_mem_bbm_unplug_bb(struct virtio_mem *vm, unsigned long bb_id)
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{
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const uint64_t addr = virtio_mem_bb_id_to_phys(vm, bb_id);
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const uint64_t size = vm->bbm.bb_size;
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return virtio_mem_send_unplug_request(vm, addr, size);
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}
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/*
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* Request to plug a big block.
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*
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* Will not modify the state of the big block.
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*/
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static int virtio_mem_bbm_plug_bb(struct virtio_mem *vm, unsigned long bb_id)
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{
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const uint64_t addr = virtio_mem_bb_id_to_phys(vm, bb_id);
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const uint64_t size = vm->bbm.bb_size;
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||||
|
||||
return virtio_mem_send_plug_request(vm, addr, size);
|
||||
}
|
||||
|
||||
/*
|
||||
* Unplug the desired number of plugged subblocks of a offline or not-added
|
||||
* memory block. Will fail if any subblock cannot get unplugged (instead of
|
||||
|
@ -1363,10 +1541,7 @@ static int virtio_mem_sbm_plug_any_sb(struct virtio_mem *vm,
|
|||
return 0;
|
||||
}
|
||||
|
||||
/*
|
||||
* Try to plug the requested amount of memory.
|
||||
*/
|
||||
static int virtio_mem_plug_request(struct virtio_mem *vm, uint64_t diff)
|
||||
static int virtio_mem_sbm_plug_request(struct virtio_mem *vm, uint64_t diff)
|
||||
{
|
||||
uint64_t nb_sb = diff / vm->sbm.sb_size;
|
||||
unsigned long mb_id;
|
||||
|
@ -1433,6 +1608,112 @@ static int virtio_mem_plug_request(struct virtio_mem *vm, uint64_t diff)
|
|||
return rc;
|
||||
}
|
||||
|
||||
/*
|
||||
* Plug a big block and add it to Linux.
|
||||
*
|
||||
* Will modify the state of the big block.
|
||||
*/
|
||||
static int virtio_mem_bbm_plug_and_add_bb(struct virtio_mem *vm,
|
||||
unsigned long bb_id)
|
||||
{
|
||||
int rc;
|
||||
|
||||
if (WARN_ON_ONCE(virtio_mem_bbm_get_bb_state(vm, bb_id) !=
|
||||
VIRTIO_MEM_BBM_BB_UNUSED))
|
||||
return -EINVAL;
|
||||
|
||||
rc = virtio_mem_bbm_plug_bb(vm, bb_id);
|
||||
if (rc)
|
||||
return rc;
|
||||
virtio_mem_bbm_set_bb_state(vm, bb_id, VIRTIO_MEM_BBM_BB_ADDED);
|
||||
|
||||
rc = virtio_mem_bbm_add_bb(vm, bb_id);
|
||||
if (rc) {
|
||||
if (!virtio_mem_bbm_unplug_bb(vm, bb_id))
|
||||
virtio_mem_bbm_set_bb_state(vm, bb_id,
|
||||
VIRTIO_MEM_BBM_BB_UNUSED);
|
||||
else
|
||||
/* Retry from the main loop. */
|
||||
virtio_mem_bbm_set_bb_state(vm, bb_id,
|
||||
VIRTIO_MEM_BBM_BB_PLUGGED);
|
||||
return rc;
|
||||
}
|
||||
return 0;
|
||||
}
|
||||
|
||||
/*
|
||||
* Prepare tracking data for the next big block.
|
||||
*/
|
||||
static int virtio_mem_bbm_prepare_next_bb(struct virtio_mem *vm,
|
||||
unsigned long *bb_id)
|
||||
{
|
||||
int rc;
|
||||
|
||||
if (vm->bbm.next_bb_id > vm->bbm.last_usable_bb_id)
|
||||
return -ENOSPC;
|
||||
|
||||
/* Resize the big block state array if required. */
|
||||
rc = virtio_mem_bbm_bb_states_prepare_next_bb(vm);
|
||||
if (rc)
|
||||
return rc;
|
||||
|
||||
vm->bbm.bb_count[VIRTIO_MEM_BBM_BB_UNUSED]++;
|
||||
*bb_id = vm->bbm.next_bb_id;
|
||||
vm->bbm.next_bb_id++;
|
||||
return 0;
|
||||
}
|
||||
|
||||
static int virtio_mem_bbm_plug_request(struct virtio_mem *vm, uint64_t diff)
|
||||
{
|
||||
uint64_t nb_bb = diff / vm->bbm.bb_size;
|
||||
unsigned long bb_id;
|
||||
int rc;
|
||||
|
||||
if (!nb_bb)
|
||||
return 0;
|
||||
|
||||
/* Try to plug and add unused big blocks */
|
||||
virtio_mem_bbm_for_each_bb(vm, bb_id, VIRTIO_MEM_BBM_BB_UNUSED) {
|
||||
if (!virtio_mem_could_add_memory(vm, vm->bbm.bb_size))
|
||||
return -ENOSPC;
|
||||
|
||||
rc = virtio_mem_bbm_plug_and_add_bb(vm, bb_id);
|
||||
if (!rc)
|
||||
nb_bb--;
|
||||
if (rc || !nb_bb)
|
||||
return rc;
|
||||
cond_resched();
|
||||
}
|
||||
|
||||
/* Try to prepare, plug and add new big blocks */
|
||||
while (nb_bb) {
|
||||
if (!virtio_mem_could_add_memory(vm, vm->bbm.bb_size))
|
||||
return -ENOSPC;
|
||||
|
||||
rc = virtio_mem_bbm_prepare_next_bb(vm, &bb_id);
|
||||
if (rc)
|
||||
return rc;
|
||||
rc = virtio_mem_bbm_plug_and_add_bb(vm, bb_id);
|
||||
if (!rc)
|
||||
nb_bb--;
|
||||
if (rc)
|
||||
return rc;
|
||||
cond_resched();
|
||||
}
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
/*
|
||||
* Try to plug the requested amount of memory.
|
||||
*/
|
||||
static int virtio_mem_plug_request(struct virtio_mem *vm, uint64_t diff)
|
||||
{
|
||||
if (vm->in_sbm)
|
||||
return virtio_mem_sbm_plug_request(vm, diff);
|
||||
return virtio_mem_bbm_plug_request(vm, diff);
|
||||
}
|
||||
|
||||
/*
|
||||
* Unplug the desired number of plugged subblocks of an offline memory block.
|
||||
* Will fail if any subblock cannot get unplugged (instead of skipping it).
|
||||
|
@ -1571,10 +1852,7 @@ static int virtio_mem_sbm_unplug_any_sb_online(struct virtio_mem *vm,
|
|||
return 0;
|
||||
}
|
||||
|
||||
/*
|
||||
* Try to unplug the requested amount of memory.
|
||||
*/
|
||||
static int virtio_mem_unplug_request(struct virtio_mem *vm, uint64_t diff)
|
||||
static int virtio_mem_sbm_unplug_request(struct virtio_mem *vm, uint64_t diff)
|
||||
{
|
||||
uint64_t nb_sb = diff / vm->sbm.sb_size;
|
||||
unsigned long mb_id;
|
||||
|
@ -1640,20 +1918,42 @@ static int virtio_mem_unplug_request(struct virtio_mem *vm, uint64_t diff)
|
|||
return rc;
|
||||
}
|
||||
|
||||
/*
|
||||
* Try to unplug the requested amount of memory.
|
||||
*/
|
||||
static int virtio_mem_unplug_request(struct virtio_mem *vm, uint64_t diff)
|
||||
{
|
||||
if (vm->in_sbm)
|
||||
return virtio_mem_sbm_unplug_request(vm, diff);
|
||||
return -EBUSY;
|
||||
}
|
||||
|
||||
/*
|
||||
* Try to unplug all blocks that couldn't be unplugged before, for example,
|
||||
* because the hypervisor was busy.
|
||||
*/
|
||||
static int virtio_mem_unplug_pending_mb(struct virtio_mem *vm)
|
||||
{
|
||||
unsigned long mb_id;
|
||||
unsigned long id;
|
||||
int rc;
|
||||
|
||||
virtio_mem_sbm_for_each_mb(vm, mb_id, VIRTIO_MEM_SBM_MB_PLUGGED) {
|
||||
rc = virtio_mem_sbm_unplug_mb(vm, mb_id);
|
||||
if (!vm->in_sbm) {
|
||||
virtio_mem_bbm_for_each_bb(vm, id,
|
||||
VIRTIO_MEM_BBM_BB_PLUGGED) {
|
||||
rc = virtio_mem_bbm_unplug_bb(vm, id);
|
||||
if (rc)
|
||||
return rc;
|
||||
virtio_mem_bbm_set_bb_state(vm, id,
|
||||
VIRTIO_MEM_BBM_BB_UNUSED);
|
||||
}
|
||||
return 0;
|
||||
}
|
||||
|
||||
virtio_mem_sbm_for_each_mb(vm, id, VIRTIO_MEM_SBM_MB_PLUGGED) {
|
||||
rc = virtio_mem_sbm_unplug_mb(vm, id);
|
||||
if (rc)
|
||||
return rc;
|
||||
virtio_mem_sbm_set_mb_state(vm, mb_id,
|
||||
virtio_mem_sbm_set_mb_state(vm, id,
|
||||
VIRTIO_MEM_SBM_MB_UNUSED);
|
||||
}
|
||||
|
||||
|
@ -1679,7 +1979,13 @@ static void virtio_mem_refresh_config(struct virtio_mem *vm)
|
|||
usable_region_size, &usable_region_size);
|
||||
end_addr = vm->addr + usable_region_size;
|
||||
end_addr = min(end_addr, phys_limit);
|
||||
vm->sbm.last_usable_mb_id = virtio_mem_phys_to_mb_id(end_addr) - 1;
|
||||
|
||||
if (vm->in_sbm)
|
||||
vm->sbm.last_usable_mb_id =
|
||||
virtio_mem_phys_to_mb_id(end_addr) - 1;
|
||||
else
|
||||
vm->bbm.last_usable_bb_id =
|
||||
virtio_mem_phys_to_bb_id(vm, end_addr) - 1;
|
||||
|
||||
/* see if there is a request to change the size */
|
||||
virtio_cread_le(vm->vdev, struct virtio_mem_config, requested_size,
|
||||
|
@ -1802,6 +2108,7 @@ static int virtio_mem_init_vq(struct virtio_mem *vm)
|
|||
static int virtio_mem_init(struct virtio_mem *vm)
|
||||
{
|
||||
const uint64_t phys_limit = 1UL << MAX_PHYSMEM_BITS;
|
||||
uint64_t sb_size, addr;
|
||||
uint16_t node_id;
|
||||
|
||||
if (!vm->vdev->config->get) {
|
||||
|
@ -1834,16 +2141,6 @@ static int virtio_mem_init(struct virtio_mem *vm)
|
|||
if (vm->nid == NUMA_NO_NODE)
|
||||
vm->nid = memory_add_physaddr_to_nid(vm->addr);
|
||||
|
||||
/*
|
||||
* We always hotplug memory in memory block granularity. This way,
|
||||
* we have to wait for exactly one memory block to online.
|
||||
*/
|
||||
if (vm->device_block_size > memory_block_size_bytes()) {
|
||||
dev_err(&vm->vdev->dev,
|
||||
"The block size is not supported (too big).\n");
|
||||
return -EINVAL;
|
||||
}
|
||||
|
||||
/* bad device setup - warn only */
|
||||
if (!IS_ALIGNED(vm->addr, memory_block_size_bytes()))
|
||||
dev_warn(&vm->vdev->dev,
|
||||
|
@ -1863,20 +2160,35 @@ static int virtio_mem_init(struct virtio_mem *vm)
|
|||
* - Is required for now for alloc_contig_range() to work reliably -
|
||||
* it doesn't properly handle smaller granularity on ZONE_NORMAL.
|
||||
*/
|
||||
vm->sbm.sb_size = max_t(uint64_t, MAX_ORDER_NR_PAGES,
|
||||
pageblock_nr_pages) * PAGE_SIZE;
|
||||
vm->sbm.sb_size = max_t(uint64_t, vm->device_block_size,
|
||||
vm->sbm.sb_size);
|
||||
vm->sbm.sbs_per_mb = memory_block_size_bytes() / vm->sbm.sb_size;
|
||||
sb_size = max_t(uint64_t, MAX_ORDER_NR_PAGES,
|
||||
pageblock_nr_pages) * PAGE_SIZE;
|
||||
sb_size = max_t(uint64_t, vm->device_block_size, sb_size);
|
||||
|
||||
/* Round up to the next full memory block */
|
||||
vm->sbm.first_mb_id = virtio_mem_phys_to_mb_id(vm->addr - 1 +
|
||||
memory_block_size_bytes());
|
||||
vm->sbm.next_mb_id = vm->sbm.first_mb_id;
|
||||
if (sb_size < memory_block_size_bytes()) {
|
||||
/* SBM: At least two subblocks per Linux memory block. */
|
||||
vm->in_sbm = true;
|
||||
vm->sbm.sb_size = sb_size;
|
||||
vm->sbm.sbs_per_mb = memory_block_size_bytes() /
|
||||
vm->sbm.sb_size;
|
||||
|
||||
/* Round up to the next full memory block */
|
||||
addr = vm->addr + memory_block_size_bytes() - 1;
|
||||
vm->sbm.first_mb_id = virtio_mem_phys_to_mb_id(addr);
|
||||
vm->sbm.next_mb_id = vm->sbm.first_mb_id;
|
||||
} else {
|
||||
/* BBM: At least one Linux memory block. */
|
||||
vm->bbm.bb_size = vm->device_block_size;
|
||||
|
||||
vm->bbm.first_bb_id = virtio_mem_phys_to_bb_id(vm, vm->addr);
|
||||
vm->bbm.next_bb_id = vm->bbm.first_bb_id;
|
||||
}
|
||||
|
||||
/* Prepare the offline threshold - make sure we can add two blocks. */
|
||||
vm->offline_threshold = max_t(uint64_t, 2 * memory_block_size_bytes(),
|
||||
VIRTIO_MEM_DEFAULT_OFFLINE_THRESHOLD);
|
||||
/* In BBM, we also want at least two big blocks. */
|
||||
vm->offline_threshold = max_t(uint64_t, 2 * vm->bbm.bb_size,
|
||||
vm->offline_threshold);
|
||||
|
||||
dev_info(&vm->vdev->dev, "start address: 0x%llx", vm->addr);
|
||||
dev_info(&vm->vdev->dev, "region size: 0x%llx", vm->region_size);
|
||||
|
@ -1884,8 +2196,12 @@ static int virtio_mem_init(struct virtio_mem *vm)
|
|||
(unsigned long long)vm->device_block_size);
|
||||
dev_info(&vm->vdev->dev, "memory block size: 0x%lx",
|
||||
memory_block_size_bytes());
|
||||
dev_info(&vm->vdev->dev, "subblock size: 0x%llx",
|
||||
(unsigned long long)vm->sbm.sb_size);
|
||||
if (vm->in_sbm)
|
||||
dev_info(&vm->vdev->dev, "subblock size: 0x%llx",
|
||||
(unsigned long long)vm->sbm.sb_size);
|
||||
else
|
||||
dev_info(&vm->vdev->dev, "big block size: 0x%llx",
|
||||
(unsigned long long)vm->bbm.bb_size);
|
||||
if (vm->nid != NUMA_NO_NODE && IS_ENABLED(CONFIG_NUMA))
|
||||
dev_info(&vm->vdev->dev, "nid: %d", vm->nid);
|
||||
|
||||
|
@ -2042,22 +2358,24 @@ static void virtio_mem_remove(struct virtio_device *vdev)
|
|||
cancel_work_sync(&vm->wq);
|
||||
hrtimer_cancel(&vm->retry_timer);
|
||||
|
||||
/*
|
||||
* After we unregistered our callbacks, user space can online partially
|
||||
* plugged offline blocks. Make sure to remove them.
|
||||
*/
|
||||
virtio_mem_sbm_for_each_mb(vm, mb_id,
|
||||
VIRTIO_MEM_SBM_MB_OFFLINE_PARTIAL) {
|
||||
rc = virtio_mem_sbm_remove_mb(vm, mb_id);
|
||||
BUG_ON(rc);
|
||||
virtio_mem_sbm_set_mb_state(vm, mb_id,
|
||||
VIRTIO_MEM_SBM_MB_UNUSED);
|
||||
if (vm->in_sbm) {
|
||||
/*
|
||||
* After we unregistered our callbacks, user space can online
|
||||
* partially plugged offline blocks. Make sure to remove them.
|
||||
*/
|
||||
virtio_mem_sbm_for_each_mb(vm, mb_id,
|
||||
VIRTIO_MEM_SBM_MB_OFFLINE_PARTIAL) {
|
||||
rc = virtio_mem_sbm_remove_mb(vm, mb_id);
|
||||
BUG_ON(rc);
|
||||
virtio_mem_sbm_set_mb_state(vm, mb_id,
|
||||
VIRTIO_MEM_SBM_MB_UNUSED);
|
||||
}
|
||||
/*
|
||||
* After we unregistered our callbacks, user space can no longer
|
||||
* offline partially plugged online memory blocks. No need to
|
||||
* worry about them.
|
||||
*/
|
||||
}
|
||||
/*
|
||||
* After we unregistered our callbacks, user space can no longer
|
||||
* offline partially plugged online memory blocks. No need to worry
|
||||
* about them.
|
||||
*/
|
||||
|
||||
/* unregister callbacks */
|
||||
unregister_virtio_mem_device(vm);
|
||||
|
@ -2076,8 +2394,12 @@ static void virtio_mem_remove(struct virtio_device *vdev)
|
|||
}
|
||||
|
||||
/* remove all tracking data - no locking needed */
|
||||
vfree(vm->sbm.mb_states);
|
||||
vfree(vm->sbm.sb_states);
|
||||
if (vm->in_sbm) {
|
||||
vfree(vm->sbm.mb_states);
|
||||
vfree(vm->sbm.sb_states);
|
||||
} else {
|
||||
vfree(vm->bbm.bb_states);
|
||||
}
|
||||
|
||||
/* reset the device and cleanup the queues */
|
||||
vdev->config->reset(vdev);
|
||||
|
|
Loading…
Reference in New Issue