diff options
| author | Stefan Hajnoczi <stefanha@redhat.com> | 2021-01-04 17:13:18 +0000 |
|---|---|---|
| committer | Eduardo Habkost <ehabkost@redhat.com> | 2021-02-01 17:07:34 -0500 |
| commit | 369d6dc4de45b8e5e35a851f5719e7fd59a0462f (patch) | |
| tree | 9b7bf91786c4866c63bab05090e83964a7bbbf33 /softmmu/memory.c | |
| parent | 74208cd252c5da9d867270a178799abd802b9338 (diff) | |
memory: add readonly support to memory_region_init_ram_from_file()
There is currently no way to open(O_RDONLY) and mmap(PROT_READ) when
creating a memory region from a file. This functionality is needed since
the underlying host file may not allow writing.
Add a bool readonly argument to memory_region_init_ram_from_file() and
the APIs it calls.
Extend memory_region_init_ram_from_file() rather than introducing a
memory_region_init_rom_from_file() API so that callers can easily make a
choice between read/write and read-only at runtime without calling
different APIs.
No new RAMBlock flag is introduced for read-only because it's unclear
whether RAMBlocks need to know that they are read-only. Pass a bool
readonly argument instead.
Both of these design decisions can be changed in the future. It just
seemed like the simplest approach to me.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: Liam Merwick <liam.merwick@oracle.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Message-Id: <20210104171320.575838-2-stefanha@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Diffstat (limited to 'softmmu/memory.c')
| -rw-r--r-- | softmmu/memory.c | 7 |
1 files changed, 5 insertions, 2 deletions
diff --git a/softmmu/memory.c b/softmmu/memory.c index 333e1ed7b0..676c298b60 100644 --- a/softmmu/memory.c +++ b/softmmu/memory.c @@ -1587,15 +1587,18 @@ void memory_region_init_ram_from_file(MemoryRegion *mr, uint64_t align, uint32_t ram_flags, const char *path, + bool readonly, Error **errp) { Error *err = NULL; memory_region_init(mr, owner, name, size); mr->ram = true; + mr->readonly = readonly; mr->terminates = true; mr->destructor = memory_region_destructor_ram; mr->align = align; - mr->ram_block = qemu_ram_alloc_from_file(size, mr, ram_flags, path, &err); + mr->ram_block = qemu_ram_alloc_from_file(size, mr, ram_flags, path, + readonly, &err); if (err) { mr->size = int128_zero(); object_unparent(OBJECT(mr)); @@ -1618,7 +1621,7 @@ void memory_region_init_ram_from_fd(MemoryRegion *mr, mr->destructor = memory_region_destructor_ram; mr->ram_block = qemu_ram_alloc_from_fd(size, mr, share ? RAM_SHARED : 0, - fd, &err); + fd, false, &err); if (err) { mr->size = int128_zero(); object_unparent(OBJECT(mr)); |