From f47a672a72acd6e2712031f0bc4d4f3ae4b6302c Mon Sep 17 00:00:00 2001 From: Chenyi Qiang Date: Thu, 12 Jun 2025 16:27:42 +0800 Subject: memory: Export a helper to get intersection of a MemoryRegionSection with a given range Rename the helper to memory_region_section_intersect_range() to make it more generic. Meanwhile, define the @end as Int128 and replace the related operations with Int128_* format since the helper is exported as a wider API. Suggested-by: Alexey Kardashevskiy Reviewed-by: Alexey Kardashevskiy Reviewed-by: Pankaj Gupta Reviewed-by: David Hildenbrand Reviewed-by: Zhao Liu Reviewed-by: Xiaoyao Li Signed-off-by: Chenyi Qiang Link: https://lore.kernel.org/r/20250612082747.51539-2-chenyi.qiang@intel.com Signed-off-by: Peter Xu --- hw/virtio/virtio-mem.c | 32 +++++--------------------------- 1 file changed, 5 insertions(+), 27 deletions(-) (limited to 'hw') diff --git a/hw/virtio/virtio-mem.c b/hw/virtio/virtio-mem.c index a3d1a67..b3c126e 100644 --- a/hw/virtio/virtio-mem.c +++ b/hw/virtio/virtio-mem.c @@ -244,28 +244,6 @@ static int virtio_mem_for_each_plugged_range(VirtIOMEM *vmem, void *arg, return ret; } -/* - * Adjust the memory section to cover the intersection with the given range. - * - * Returns false if the intersection is empty, otherwise returns true. - */ -static bool virtio_mem_intersect_memory_section(MemoryRegionSection *s, - uint64_t offset, uint64_t size) -{ - uint64_t start = MAX(s->offset_within_region, offset); - uint64_t end = MIN(s->offset_within_region + int128_get64(s->size), - offset + size); - - if (end <= start) { - return false; - } - - s->offset_within_address_space += start - s->offset_within_region; - s->offset_within_region = start; - s->size = int128_make64(end - start); - return true; -} - typedef int (*virtio_mem_section_cb)(MemoryRegionSection *s, void *arg); static int virtio_mem_for_each_plugged_section(const VirtIOMEM *vmem, @@ -287,7 +265,7 @@ static int virtio_mem_for_each_plugged_section(const VirtIOMEM *vmem, first_bit + 1) - 1; size = (last_bit - first_bit + 1) * vmem->block_size; - if (!virtio_mem_intersect_memory_section(&tmp, offset, size)) { + if (!memory_region_section_intersect_range(&tmp, offset, size)) { break; } ret = cb(&tmp, arg); @@ -319,7 +297,7 @@ static int virtio_mem_for_each_unplugged_section(const VirtIOMEM *vmem, first_bit + 1) - 1; size = (last_bit - first_bit + 1) * vmem->block_size; - if (!virtio_mem_intersect_memory_section(&tmp, offset, size)) { + if (!memory_region_section_intersect_range(&tmp, offset, size)) { break; } ret = cb(&tmp, arg); @@ -355,7 +333,7 @@ static void virtio_mem_notify_unplug(VirtIOMEM *vmem, uint64_t offset, QLIST_FOREACH(rdl, &vmem->rdl_list, next) { MemoryRegionSection tmp = *rdl->section; - if (!virtio_mem_intersect_memory_section(&tmp, offset, size)) { + if (!memory_region_section_intersect_range(&tmp, offset, size)) { continue; } rdl->notify_discard(rdl, &tmp); @@ -371,7 +349,7 @@ static int virtio_mem_notify_plug(VirtIOMEM *vmem, uint64_t offset, QLIST_FOREACH(rdl, &vmem->rdl_list, next) { MemoryRegionSection tmp = *rdl->section; - if (!virtio_mem_intersect_memory_section(&tmp, offset, size)) { + if (!memory_region_section_intersect_range(&tmp, offset, size)) { continue; } ret = rdl->notify_populate(rdl, &tmp); @@ -388,7 +366,7 @@ static int virtio_mem_notify_plug(VirtIOMEM *vmem, uint64_t offset, if (rdl2 == rdl) { break; } - if (!virtio_mem_intersect_memory_section(&tmp, offset, size)) { + if (!memory_region_section_intersect_range(&tmp, offset, size)) { continue; } rdl2->notify_discard(rdl2, &tmp); -- cgit v1.1 From ff1211154c45c9f7f82116ae9a8c72a848e4a8b5 Mon Sep 17 00:00:00 2001 From: Chenyi Qiang Date: Thu, 12 Jun 2025 16:27:43 +0800 Subject: memory: Change memory_region_set_ram_discard_manager() to return the result Modify memory_region_set_ram_discard_manager() to return -EBUSY if a RamDiscardManager is already set in the MemoryRegion. The caller must handle this failure, such as having virtio-mem undo its actions and fail the realize() process. Opportunistically move the call earlier to avoid complex error handling. This change is beneficial when introducing a new RamDiscardManager instance besides virtio-mem. After ram_block_coordinated_discard_require(true) unlocks all RamDiscardManager instances, only one instance is allowed to be set for one MemoryRegion at present. Suggested-by: David Hildenbrand Reviewed-by: David Hildenbrand Reviewed-by: Pankaj Gupta Tested-by: Alexey Kardashevskiy Reviewed-by: Alexey Kardashevskiy Reviewed-by: Xiaoyao Li Signed-off-by: Chenyi Qiang Link: https://lore.kernel.org/r/20250612082747.51539-3-chenyi.qiang@intel.com Signed-off-by: Peter Xu --- hw/virtio/virtio-mem.c | 30 +++++++++++++++++------------- 1 file changed, 17 insertions(+), 13 deletions(-) (limited to 'hw') diff --git a/hw/virtio/virtio-mem.c b/hw/virtio/virtio-mem.c index b3c126e..2e491e8 100644 --- a/hw/virtio/virtio-mem.c +++ b/hw/virtio/virtio-mem.c @@ -1048,6 +1048,17 @@ static void virtio_mem_device_realize(DeviceState *dev, Error **errp) } /* + * Set ourselves as RamDiscardManager before the plug handler maps the + * memory region and exposes it via an address space. + */ + if (memory_region_set_ram_discard_manager(&vmem->memdev->mr, + RAM_DISCARD_MANAGER(vmem))) { + error_setg(errp, "Failed to set RamDiscardManager"); + ram_block_coordinated_discard_require(false); + return; + } + + /* * We don't know at this point whether shared RAM is migrated using * QEMU or migrated using the file content. "x-ignore-shared" will be * configured after realizing the device. So in case we have an @@ -1061,6 +1072,7 @@ static void virtio_mem_device_realize(DeviceState *dev, Error **errp) ret = ram_block_discard_range(rb, 0, qemu_ram_get_used_length(rb)); if (ret) { error_setg_errno(errp, -ret, "Unexpected error discarding RAM"); + memory_region_set_ram_discard_manager(&vmem->memdev->mr, NULL); ram_block_coordinated_discard_require(false); return; } @@ -1122,13 +1134,6 @@ static void virtio_mem_device_realize(DeviceState *dev, Error **errp) vmem->system_reset = VIRTIO_MEM_SYSTEM_RESET(obj); vmem->system_reset->vmem = vmem; qemu_register_resettable(obj); - - /* - * Set ourselves as RamDiscardManager before the plug handler maps the - * memory region and exposes it via an address space. - */ - memory_region_set_ram_discard_manager(&vmem->memdev->mr, - RAM_DISCARD_MANAGER(vmem)); } static void virtio_mem_device_unrealize(DeviceState *dev) @@ -1136,12 +1141,6 @@ static void virtio_mem_device_unrealize(DeviceState *dev) VirtIODevice *vdev = VIRTIO_DEVICE(dev); VirtIOMEM *vmem = VIRTIO_MEM(dev); - /* - * The unplug handler unmapped the memory region, it cannot be - * found via an address space anymore. Unset ourselves. - */ - memory_region_set_ram_discard_manager(&vmem->memdev->mr, NULL); - qemu_unregister_resettable(OBJECT(vmem->system_reset)); object_unref(OBJECT(vmem->system_reset)); @@ -1154,6 +1153,11 @@ static void virtio_mem_device_unrealize(DeviceState *dev) virtio_del_queue(vdev, 0); virtio_cleanup(vdev); g_free(vmem->bitmap); + /* + * The unplug handler unmapped the memory region, it cannot be + * found via an address space anymore. Unset ourselves. + */ + memory_region_set_ram_discard_manager(&vmem->memdev->mr, NULL); ram_block_coordinated_discard_require(false); } -- cgit v1.1 From 2205b8466733f8c6e3306c964f31c5a7cac69dfa Mon Sep 17 00:00:00 2001 From: Chenyi Qiang Date: Thu, 12 Jun 2025 16:27:44 +0800 Subject: memory: Unify the definiton of ReplayRamPopulate() and ReplayRamDiscard() Update ReplayRamDiscard() function to return the result and unify the ReplayRamPopulate() and ReplayRamDiscard() to ReplayRamDiscardState() at the same time due to their identical definitions. This unification simplifies related structures, such as VirtIOMEMReplayData, which makes it cleaner. Reviewed-by: David Hildenbrand Reviewed-by: Pankaj Gupta Reviewed-by: Xiaoyao Li Signed-off-by: Chenyi Qiang Link: https://lore.kernel.org/r/20250612082747.51539-4-chenyi.qiang@intel.com Signed-off-by: Peter Xu --- hw/virtio/virtio-mem.c | 21 ++++++++++----------- 1 file changed, 10 insertions(+), 11 deletions(-) (limited to 'hw') diff --git a/hw/virtio/virtio-mem.c b/hw/virtio/virtio-mem.c index 2e491e8..c46f6f9 100644 --- a/hw/virtio/virtio-mem.c +++ b/hw/virtio/virtio-mem.c @@ -1732,7 +1732,7 @@ static bool virtio_mem_rdm_is_populated(const RamDiscardManager *rdm, } struct VirtIOMEMReplayData { - void *fn; + ReplayRamDiscardState fn; void *opaque; }; @@ -1740,12 +1740,12 @@ static int virtio_mem_rdm_replay_populated_cb(MemoryRegionSection *s, void *arg) { struct VirtIOMEMReplayData *data = arg; - return ((ReplayRamPopulate)data->fn)(s, data->opaque); + return data->fn(s, data->opaque); } static int virtio_mem_rdm_replay_populated(const RamDiscardManager *rdm, MemoryRegionSection *s, - ReplayRamPopulate replay_fn, + ReplayRamDiscardState replay_fn, void *opaque) { const VirtIOMEM *vmem = VIRTIO_MEM(rdm); @@ -1764,14 +1764,13 @@ static int virtio_mem_rdm_replay_discarded_cb(MemoryRegionSection *s, { struct VirtIOMEMReplayData *data = arg; - ((ReplayRamDiscard)data->fn)(s, data->opaque); - return 0; + return data->fn(s, data->opaque); } -static void virtio_mem_rdm_replay_discarded(const RamDiscardManager *rdm, - MemoryRegionSection *s, - ReplayRamDiscard replay_fn, - void *opaque) +static int virtio_mem_rdm_replay_discarded(const RamDiscardManager *rdm, + MemoryRegionSection *s, + ReplayRamDiscardState replay_fn, + void *opaque) { const VirtIOMEM *vmem = VIRTIO_MEM(rdm); struct VirtIOMEMReplayData data = { @@ -1780,8 +1779,8 @@ static void virtio_mem_rdm_replay_discarded(const RamDiscardManager *rdm, }; g_assert(s->mr == &vmem->memdev->mr); - virtio_mem_for_each_unplugged_section(vmem, s, &data, - virtio_mem_rdm_replay_discarded_cb); + return virtio_mem_for_each_unplugged_section(vmem, s, &data, + virtio_mem_rdm_replay_discarded_cb); } static void virtio_mem_rdm_register_listener(RamDiscardManager *rdm, -- cgit v1.1