From 7a9d5d0282c7f64b3e728c99edbacf9806fdba2c Mon Sep 17 00:00:00 2001 From: David Hildenbrand Date: Tue, 13 Apr 2021 11:55:21 +0200 Subject: [PATCH] virtio-mem: Factor out traversing unplugged ranges Let's factor out the core logic, no need to replicate. Reviewed-by: Pankaj Gupta Acked-by: Michael S. Tsirkin Reviewed-by: Michael S. Tsirkin Cc: Paolo Bonzini Cc: "Michael S. Tsirkin" Cc: Alex Williamson Cc: Dr. David Alan Gilbert Cc: Igor Mammedov Cc: Pankaj Gupta Cc: Peter Xu Cc: Auger Eric Cc: Wei Yang Cc: teawater Cc: Marek Kedzierski Signed-off-by: David Hildenbrand Message-Id: <20210413095531.25603-4-david@redhat.com> Signed-off-by: Eduardo Habkost --- hw/virtio/virtio-mem.c | 86 ++++++++++++++++++++++++------------------ 1 file changed, 49 insertions(+), 37 deletions(-) diff --git a/hw/virtio/virtio-mem.c b/hw/virtio/virtio-mem.c index 75aa7d6f1b..3942fd7549 100644 --- a/hw/virtio/virtio-mem.c +++ b/hw/virtio/virtio-mem.c @@ -145,6 +145,33 @@ static bool virtio_mem_is_busy(void) return migration_in_incoming_postcopy() || !migration_is_idle(); } +typedef int (*virtio_mem_range_cb)(const VirtIOMEM *vmem, void *arg, + uint64_t offset, uint64_t size); + +static int virtio_mem_for_each_unplugged_range(const VirtIOMEM *vmem, void *arg, + virtio_mem_range_cb cb) +{ + unsigned long first_zero_bit, last_zero_bit; + uint64_t offset, size; + int ret = 0; + + first_zero_bit = find_first_zero_bit(vmem->bitmap, vmem->bitmap_size); + while (first_zero_bit < vmem->bitmap_size) { + offset = first_zero_bit * vmem->block_size; + last_zero_bit = find_next_bit(vmem->bitmap, vmem->bitmap_size, + first_zero_bit + 1) - 1; + size = (last_zero_bit - first_zero_bit + 1) * vmem->block_size; + + ret = cb(vmem, arg, offset, size); + if (ret) { + break; + } + first_zero_bit = find_next_zero_bit(vmem->bitmap, vmem->bitmap_size, + last_zero_bit + 2); + } + return ret; +} + static bool virtio_mem_test_bitmap(VirtIOMEM *vmem, uint64_t start_gpa, uint64_t size, bool plugged) { @@ -594,33 +621,27 @@ static void virtio_mem_device_unrealize(DeviceState *dev) ram_block_discard_require(false); } -static int virtio_mem_restore_unplugged(VirtIOMEM *vmem) +static int virtio_mem_discard_range_cb(const VirtIOMEM *vmem, void *arg, + uint64_t offset, uint64_t size) { RAMBlock *rb = vmem->memdev->mr.ram_block; - unsigned long first_zero_bit, last_zero_bit; - uint64_t offset, length; int ret; - /* Find consecutive unplugged blocks and discard the consecutive range. */ - first_zero_bit = find_first_zero_bit(vmem->bitmap, vmem->bitmap_size); - while (first_zero_bit < vmem->bitmap_size) { - offset = first_zero_bit * vmem->block_size; - last_zero_bit = find_next_bit(vmem->bitmap, vmem->bitmap_size, - first_zero_bit + 1) - 1; - length = (last_zero_bit - first_zero_bit + 1) * vmem->block_size; - - ret = ram_block_discard_range(rb, offset, length); - if (ret) { - error_report("Unexpected error discarding RAM: %s", - strerror(-ret)); - return -EINVAL; - } - first_zero_bit = find_next_zero_bit(vmem->bitmap, vmem->bitmap_size, - last_zero_bit + 2); + ret = ram_block_discard_range(rb, offset, size); + if (ret) { + error_report("Unexpected error discarding RAM: %s", strerror(-ret)); + return -EINVAL; } return 0; } +static int virtio_mem_restore_unplugged(VirtIOMEM *vmem) +{ + /* Make sure all memory is really discarded after migration. */ + return virtio_mem_for_each_unplugged_range(vmem, NULL, + virtio_mem_discard_range_cb); +} + static int virtio_mem_post_load(void *opaque, int version_id) { if (migration_in_incoming_postcopy()) { @@ -872,28 +893,19 @@ static void virtio_mem_set_block_size(Object *obj, Visitor *v, const char *name, vmem->block_size = value; } -static void virtio_mem_precopy_exclude_unplugged(VirtIOMEM *vmem) +static int virtio_mem_precopy_exclude_range_cb(const VirtIOMEM *vmem, void *arg, + uint64_t offset, uint64_t size) { void * const host = qemu_ram_get_host_addr(vmem->memdev->mr.ram_block); - unsigned long first_zero_bit, last_zero_bit; - uint64_t offset, length; - /* - * Find consecutive unplugged blocks and exclude them from migration. - * - * Note: Blocks cannot get (un)plugged during precopy, no locking needed. - */ - first_zero_bit = find_first_zero_bit(vmem->bitmap, vmem->bitmap_size); - while (first_zero_bit < vmem->bitmap_size) { - offset = first_zero_bit * vmem->block_size; - last_zero_bit = find_next_bit(vmem->bitmap, vmem->bitmap_size, - first_zero_bit + 1) - 1; - length = (last_zero_bit - first_zero_bit + 1) * vmem->block_size; + qemu_guest_free_page_hint(host + offset, size); + return 0; +} - qemu_guest_free_page_hint(host + offset, length); - first_zero_bit = find_next_zero_bit(vmem->bitmap, vmem->bitmap_size, - last_zero_bit + 2); - } +static void virtio_mem_precopy_exclude_unplugged(VirtIOMEM *vmem) +{ + virtio_mem_for_each_unplugged_range(vmem, NULL, + virtio_mem_precopy_exclude_range_cb); } static int virtio_mem_precopy_notify(NotifierWithReturn *n, void *data)