Commit dbdd685be9 for qemu.org
commit dbdd685be9b0789588fa7c049cc7409bcaa2d939
Author: Peter Xu <peterx@redhat.com>
Date: Tue Sep 29 18:50:10 2026 -0500
ramblock: Rename guest_memfd to guest_memfd_private
Rename the field to reflect the fact that the guest_memfd in this case only
backs private portion of the ramblock rather than all of it.
Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com>
Reviewed-by: Michael Roth <michael.roth@amd.com>
Reviewed-by: David Hildenbrand <david@kernel.org>
Signed-off-by: Michael Roth <michael.roth@amd.com>
Link: https://lore.kernel.org/r/20260929235109.1398509-5-michael.roth@amd.com
Signed-off-by: Peter Xu <peterx@redhat.com>
diff --git a/accel/kvm/kvm-all.c b/accel/kvm/kvm-all.c
index 0b1407e4ea..a29b1d7a3c 100644
--- a/accel/kvm/kvm-all.c
+++ b/accel/kvm/kvm-all.c
@@ -1729,7 +1729,7 @@ static void kvm_set_phys_mem(KVMMemoryListener *kml,
mem->ram_start_offset = ram_start_offset;
mem->ram = ram;
mem->flags = kvm_mem_flags(mr);
- mem->guest_memfd = mr->ram_block->guest_memfd;
+ mem->guest_memfd = mr->ram_block->guest_memfd_private;
mem->guest_memfd_offset = mem->guest_memfd >= 0 ?
(uint8_t*)ram - mr->ram_block->host : 0;
diff --git a/include/system/memory.h b/include/system/memory.h
index a7e03fc3e7..aef555af80 100644
--- a/include/system/memory.h
+++ b/include/system/memory.h
@@ -1507,10 +1507,11 @@ bool memory_region_skip_iommu_map(const MemoryRegion *mr);
void memory_region_set_skip_iommu_map(MemoryRegion *mr, bool skip);
/**
- * memory_region_has_guest_memfd: check whether a memory region has guest_memfd
- * associated
+ * memory_region_has_guest_memfd: check whether a memory region has
+ * guest_memfd_private associated
*
- * Returns %true if a memory region's ram_block has valid guest_memfd assigned.
+ * Returns %true if a memory region's ram_block has valid guest_memfd_private
+ * assigned.
*
* @mr: the memory region being queried
*/
diff --git a/include/system/ramblock.h b/include/system/ramblock.h
index 84624aca2c..0388d6cc6b 100644
--- a/include/system/ramblock.h
+++ b/include/system/ramblock.h
@@ -40,7 +40,12 @@ struct RAMBlock {
Error *cpr_blocker;
int fd;
uint64_t fd_offset;
- int guest_memfd;
+ /*
+ * When RAM_GUEST_MEMFD_PRIVATE flag is set, this ramblock can have
+ * private pages backed by guest_memfd_private specified, while shared
+ * pages are backed by the ramblock on its own.
+ */
+ int guest_memfd_private;
RamBlockAttributes *attributes;
size_t page_size;
/* dirty bitmap used during migration */
diff --git a/system/memory.c b/system/memory.c
index 264dc90c0a..b07d5dc542 100644
--- a/system/memory.c
+++ b/system/memory.c
@@ -1780,7 +1780,7 @@ void memory_region_set_skip_iommu_map(MemoryRegion *mr, bool skip)
bool memory_region_has_guest_memfd(const MemoryRegion *mr)
{
- return mr->ram_block && mr->ram_block->guest_memfd >= 0;
+ return mr->ram_block && mr->ram_block->guest_memfd_private >= 0;
}
uint8_t memory_region_get_dirty_log_mask(const MemoryRegion *mr)
diff --git a/system/physmem.c b/system/physmem.c
index 1b3f327ed5..156853c8db 100644
--- a/system/physmem.c
+++ b/system/physmem.c
@@ -2201,7 +2201,7 @@ static void ram_block_add(RAMBlock *new_block, Error **errp)
goto out_free;
}
- assert(new_block->guest_memfd < 0);
+ assert(new_block->guest_memfd_private < 0);
ret = ram_block_coordinated_discard_require(true);
if (ret < 0) {
@@ -2211,9 +2211,9 @@ static void ram_block_add(RAMBlock *new_block, Error **errp)
goto out_free;
}
- new_block->guest_memfd = kvm_create_guest_memfd(new_block->max_length,
- 0, errp);
- if (new_block->guest_memfd < 0) {
+ new_block->guest_memfd_private =
+ kvm_create_guest_memfd(new_block->max_length, 0, errp);
+ if (new_block->guest_memfd_private < 0) {
qemu_mutex_unlock_ramlist();
goto out_free;
}
@@ -2230,7 +2230,7 @@ static void ram_block_add(RAMBlock *new_block, Error **errp)
new_block->attributes = ram_block_attributes_create(new_block);
if (!new_block->attributes) {
error_setg(errp, "Failed to create ram block attribute");
- close(new_block->guest_memfd);
+ close(new_block->guest_memfd_private);
ram_block_coordinated_discard_require(false);
qemu_mutex_unlock_ramlist();
goto out_free;
@@ -2366,7 +2366,7 @@ RAMBlock *qemu_ram_alloc_from_fd(ram_addr_t size, ram_addr_t max_size,
new_block->max_length = max_size;
new_block->resized = resized;
new_block->flags = ram_flags;
- new_block->guest_memfd = -1;
+ new_block->guest_memfd_private = -1;
new_block->host = file_ram_alloc(new_block, max_size, fd,
file_size < offset + max_size,
offset, errp);
@@ -2539,7 +2539,7 @@ RAMBlock *qemu_ram_alloc_internal(ram_addr_t size, ram_addr_t max_size,
new_block->used_length = size;
new_block->max_length = max_size;
new_block->fd = -1;
- new_block->guest_memfd = -1;
+ new_block->guest_memfd_private = -1;
new_block->page_size = qemu_real_host_page_size();
new_block->host = host;
new_block->flags = ram_flags;
@@ -2590,8 +2590,8 @@ static void reclaim_ramblock(RAMBlock *block)
qemu_anon_ram_free(block->host, block->max_length);
}
- if (block->guest_memfd >= 0) {
- close(block->guest_memfd);
+ if (block->guest_memfd_private >= 0) {
+ close(block->guest_memfd_private);
ram_block_coordinated_discard_require(false);
}
@@ -2839,12 +2839,12 @@ int ram_block_rebind(Error **errp)
RAMBLOCK_FOREACH(block) {
if (block->flags & RAM_GUEST_MEMFD) {
- if (block->guest_memfd >= 0) {
- close(block->guest_memfd);
+ if (block->guest_memfd_private >= 0) {
+ close(block->guest_memfd_private);
}
- block->guest_memfd = kvm_create_guest_memfd(block->max_length,
- 0, errp);
- if (block->guest_memfd < 0) {
+ block->guest_memfd_private = kvm_create_guest_memfd(
+ block->max_length, 0, errp);
+ if (block->guest_memfd_private < 0) {
qemu_mutex_unlock_ramlist();
return -1;
}
@@ -4272,7 +4272,7 @@ int ram_block_discard_range(RAMBlock *rb, uint64_t offset, size_t length)
return ret;
}
- if (rb->guest_memfd >= 0) {
+ if (rb->guest_memfd_private >= 0) {
ret = ram_block_discard_guest_memfd_range(rb, offset, length);
}
@@ -4286,7 +4286,8 @@ int ram_block_discard_guest_memfd_range(RAMBlock *rb, uint64_t offset,
#ifdef CONFIG_FALLOCATE_PUNCH_HOLE
/* ignore fd_offset with guest_memfd */
- ret = fallocate(rb->guest_memfd, FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE,
+ ret = fallocate(rb->guest_memfd_private,
+ FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE,
offset, length);
if (ret) {