On 05.03.21 16:51, Peter Xu wrote:
On Fri, Mar 05, 2021 at 04:44:36PM +0100, David Hildenbrand wrote:
On 05.03.21 16:42, Peter Xu wrote:
On Fri, Mar 05, 2021 at 11:16:33AM +0100, David Hildenbrand wrote:
+#define OVERCOMMIT_MEMORY_PATH "/proc/sys/vm/overcommit_memory"
+static bool map_noreserve_effective(int fd, bool readonly, bool shared)
+{
[...]
@@ -184,8 +251,7 @@ void *qemu_ram_mmap(int fd,
size_t offset, total;
void *ptr, *guardptr;
- if (noreserve) {
- error_report("Skipping reservation of swap space is not supported");
+ if (noreserve && !map_noreserve_effective(fd, shared, readonly)) {
Need to switch "shared" & "readonly"?
Indeed, interestingly it has the same effect (as we don't have anonymous
read-only memory in QEMU :) )
But note there is still a "g_assert(!shared || fd >= 0);" inside.. :)
(wouldn't have happened with flags ... hmm)
Right.
I'll probably go with
/* Map PROT_READ instead of PROT_READ|PROT_WRITE. */
#define QEMU_RAM_MMAP_READONLY (1 << 0)
/* Map MAP_SHARED instead of MAP_PRIVATE. */
#define QEMU_RAM_MMAP_SHARED (1 << 1)
/* Map MAP_SYNC|MAP_SHARED_VALIDATE if possible, fallback and warn otherwise. */
#define QEMU_RAM_MMAP_PMEM (1 << 2)
for qemu_ram_mmap(). qemu_anon_ram_alloc() will still have bools, but
there it will at least be only two.
--
Thanks,
David / dhildenb
